From 51f3ab85e024fcd74c49d273ce5202a207577d31 Mon Sep 17 00:00:00 2001 From: Nicolas Lacasse Date: Mon, 6 Jan 2020 12:51:35 -0800 Subject: Convert memfs into proto-tmpfs. - Renamed memfs to tmpfs. - Copied fileRangeSet bits from fs/fsutil/ to fsimpl/tmpfs/ - Changed tmpfs to be backed by filemem instead of byte slice. - regularFileReadWriter uses a sync.Pool, similar to gofer client. PiperOrigin-RevId: 288356380 --- pkg/sentry/fsimpl/tmpfs/filesystem.go | 698 ++++++++++++++++++++++++++++++++++ 1 file changed, 698 insertions(+) create mode 100644 pkg/sentry/fsimpl/tmpfs/filesystem.go (limited to 'pkg/sentry/fsimpl/tmpfs/filesystem.go') diff --git a/pkg/sentry/fsimpl/tmpfs/filesystem.go b/pkg/sentry/fsimpl/tmpfs/filesystem.go new file mode 100644 index 000000000..26979729e --- /dev/null +++ b/pkg/sentry/fsimpl/tmpfs/filesystem.go @@ -0,0 +1,698 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package tmpfs + +import ( + "fmt" + "sync/atomic" + + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/fspath" + "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserror" +) + +// Sync implements vfs.FilesystemImpl.Sync. +func (fs *filesystem) Sync(ctx context.Context) error { + // All filesystem state is in-memory. + return nil +} + +// stepLocked resolves rp.Component() to an existing file, starting from the +// given directory. +// +// stepLocked is loosely analogous to fs/namei.c:walk_component(). +// +// Preconditions: filesystem.mu must be locked. !rp.Done(). +func stepLocked(rp *vfs.ResolvingPath, d *dentry) (*dentry, error) { + if !d.inode.isDir() { + return nil, syserror.ENOTDIR + } + if err := d.inode.checkPermissions(rp.Credentials(), vfs.MayExec, true); err != nil { + return nil, err + } +afterSymlink: + nextVFSD, err := rp.ResolveComponent(&d.vfsd) + if err != nil { + return nil, err + } + if nextVFSD == nil { + // Since the Dentry tree is the sole source of truth for tmpfs, if it's + // not in the Dentry tree, it doesn't exist. + return nil, syserror.ENOENT + } + next := nextVFSD.Impl().(*dentry) + if symlink, ok := next.inode.impl.(*symlink); ok && rp.ShouldFollowSymlink() { + // TODO: symlink traversals update access time + if err := rp.HandleSymlink(symlink.target); err != nil { + return nil, err + } + goto afterSymlink // don't check the current directory again + } + rp.Advance() + return next, nil +} + +// walkParentDirLocked resolves all but the last path component of rp to an +// existing directory, starting from the given directory (which is usually +// rp.Start().Impl().(*dentry)). It does not check that the returned directory +// is searchable by the provider of rp. +// +// walkParentDirLocked is loosely analogous to Linux's +// fs/namei.c:path_parentat(). +// +// Preconditions: filesystem.mu must be locked. !rp.Done(). +func walkParentDirLocked(rp *vfs.ResolvingPath, d *dentry) (*dentry, error) { + for !rp.Final() { + next, err := stepLocked(rp, d) + if err != nil { + return nil, err + } + d = next + } + if !d.inode.isDir() { + return nil, syserror.ENOTDIR + } + return d, nil +} + +// resolveLocked resolves rp to an existing file. +// +// resolveLocked is loosely analogous to Linux's fs/namei.c:path_lookupat(). +// +// Preconditions: filesystem.mu must be locked. +func resolveLocked(rp *vfs.ResolvingPath) (*dentry, error) { + d := rp.Start().Impl().(*dentry) + for !rp.Done() { + next, err := stepLocked(rp, d) + if err != nil { + return nil, err + } + d = next + } + if rp.MustBeDir() && !d.inode.isDir() { + return nil, syserror.ENOTDIR + } + return d, nil +} + +// doCreateAt checks that creating a file at rp is permitted, then invokes +// create to do so. +// +// doCreateAt is loosely analogous to a conjunction of Linux's +// fs/namei.c:filename_create() and done_path_create(). +// +// Preconditions: !rp.Done(). For the final path component in rp, +// !rp.ShouldFollowSymlink(). +func (fs *filesystem) doCreateAt(rp *vfs.ResolvingPath, dir bool, create func(parent *dentry, name string) error) error { + fs.mu.Lock() + defer fs.mu.Unlock() + parent, err := walkParentDirLocked(rp, rp.Start().Impl().(*dentry)) + if err != nil { + return err + } + if err := parent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec, true /* isDir */); err != nil { + return err + } + name := rp.Component() + if name == "." || name == ".." { + return syserror.EEXIST + } + // Call parent.vfsd.Child() instead of stepLocked() or rp.ResolveChild(), + // because if the child exists we want to return EEXIST immediately instead + // of attempting symlink/mount traversal. + if parent.vfsd.Child(name) != nil { + return syserror.EEXIST + } + if !dir && rp.MustBeDir() { + return syserror.ENOENT + } + // In memfs, the only way to cause a dentry to be disowned is by removing + // it from the filesystem, so this check is equivalent to checking if + // parent has been removed. + if parent.vfsd.IsDisowned() { + return syserror.ENOENT + } + mnt := rp.Mount() + if err := mnt.CheckBeginWrite(); err != nil { + return err + } + defer mnt.EndWrite() + return create(parent, name) +} + +// GetDentryAt implements vfs.FilesystemImpl.GetDentryAt. +func (fs *filesystem) GetDentryAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.GetDentryOptions) (*vfs.Dentry, error) { + fs.mu.RLock() + defer fs.mu.RUnlock() + d, err := resolveLocked(rp) + if err != nil { + return nil, err + } + if opts.CheckSearchable { + if !d.inode.isDir() { + return nil, syserror.ENOTDIR + } + if err := d.inode.checkPermissions(rp.Credentials(), vfs.MayExec, true /* isDir */); err != nil { + return nil, err + } + } + d.IncRef() + return &d.vfsd, nil +} + +// GetParentDentryAt implements vfs.FilesystemImpl.GetParentDentryAt. +func (fs *filesystem) GetParentDentryAt(ctx context.Context, rp *vfs.ResolvingPath) (*vfs.Dentry, error) { + fs.mu.RLock() + defer fs.mu.RUnlock() + d, err := walkParentDirLocked(rp, rp.Start().Impl().(*dentry)) + if err != nil { + return nil, err + } + d.IncRef() + return &d.vfsd, nil +} + +// LinkAt implements vfs.FilesystemImpl.LinkAt. +func (fs *filesystem) LinkAt(ctx context.Context, rp *vfs.ResolvingPath, vd vfs.VirtualDentry) error { + return fs.doCreateAt(rp, false /* dir */, func(parent *dentry, name string) error { + if rp.Mount() != vd.Mount() { + return syserror.EXDEV + } + d := vd.Dentry().Impl().(*dentry) + if d.inode.isDir() { + return syserror.EPERM + } + if d.inode.nlink == 0 { + return syserror.ENOENT + } + if d.inode.nlink == maxLinks { + return syserror.EMLINK + } + d.inode.incLinksLocked() + child := fs.newDentry(d.inode) + parent.vfsd.InsertChild(&child.vfsd, name) + parent.inode.impl.(*directory).childList.PushBack(child) + return nil + }) +} + +// MkdirAt implements vfs.FilesystemImpl.MkdirAt. +func (fs *filesystem) MkdirAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.MkdirOptions) error { + return fs.doCreateAt(rp, true /* dir */, func(parent *dentry, name string) error { + if parent.inode.nlink == maxLinks { + return syserror.EMLINK + } + parent.inode.incLinksLocked() // from child's ".." + child := fs.newDentry(fs.newDirectory(rp.Credentials(), opts.Mode)) + parent.vfsd.InsertChild(&child.vfsd, name) + parent.inode.impl.(*directory).childList.PushBack(child) + return nil + }) +} + +// MknodAt implements vfs.FilesystemImpl.MknodAt. +func (fs *filesystem) MknodAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.MknodOptions) error { + return fs.doCreateAt(rp, false /* dir */, func(parent *dentry, name string) error { + switch opts.Mode.FileType() { + case 0, linux.S_IFREG: + child := fs.newDentry(fs.newRegularFile(rp.Credentials(), opts.Mode)) + parent.vfsd.InsertChild(&child.vfsd, name) + parent.inode.impl.(*directory).childList.PushBack(child) + return nil + case linux.S_IFIFO: + child := fs.newDentry(fs.newNamedPipe(rp.Credentials(), opts.Mode)) + parent.vfsd.InsertChild(&child.vfsd, name) + parent.inode.impl.(*directory).childList.PushBack(child) + return nil + case linux.S_IFBLK, linux.S_IFCHR, linux.S_IFSOCK: + // Not yet supported. + return syserror.EPERM + default: + return syserror.EINVAL + } + }) +} + +// OpenAt implements vfs.FilesystemImpl.OpenAt. +func (fs *filesystem) OpenAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.OpenOptions) (*vfs.FileDescription, error) { + if opts.Flags&linux.O_TMPFILE != 0 { + // Not yet supported. + return nil, syserror.EOPNOTSUPP + } + + // Handle O_CREAT and !O_CREAT separately, since in the latter case we + // don't need fs.mu for writing. + if opts.Flags&linux.O_CREAT == 0 { + fs.mu.RLock() + defer fs.mu.RUnlock() + d, err := resolveLocked(rp) + if err != nil { + return nil, err + } + return d.open(ctx, rp, opts.Flags, false /* afterCreate */) + } + + mustCreate := opts.Flags&linux.O_EXCL != 0 + start := rp.Start().Impl().(*dentry) + fs.mu.Lock() + defer fs.mu.Unlock() + if rp.Done() { + // Reject attempts to open directories with O_CREAT. + if rp.MustBeDir() { + return nil, syserror.EISDIR + } + if mustCreate { + return nil, syserror.EEXIST + } + return start.open(ctx, rp, opts.Flags, false /* afterCreate */) + } +afterTrailingSymlink: + parent, err := walkParentDirLocked(rp, start) + if err != nil { + return nil, err + } + // Check for search permission in the parent directory. + if err := parent.inode.checkPermissions(rp.Credentials(), vfs.MayExec, true); err != nil { + return nil, err + } + // Reject attempts to open directories with O_CREAT. + if rp.MustBeDir() { + return nil, syserror.EISDIR + } + name := rp.Component() + if name == "." || name == ".." { + return nil, syserror.EISDIR + } + // Determine whether or not we need to create a file. + child, err := stepLocked(rp, parent) + if err == syserror.ENOENT { + // Already checked for searchability above; now check for writability. + if err := parent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite, true); err != nil { + return nil, err + } + if err := rp.Mount().CheckBeginWrite(); err != nil { + return nil, err + } + defer rp.Mount().EndWrite() + // Create and open the child. + child := fs.newDentry(fs.newRegularFile(rp.Credentials(), opts.Mode)) + parent.vfsd.InsertChild(&child.vfsd, name) + parent.inode.impl.(*directory).childList.PushBack(child) + return child.open(ctx, rp, opts.Flags, true) + } + if err != nil { + return nil, err + } + // Do we need to resolve a trailing symlink? + if !rp.Done() { + start = parent + goto afterTrailingSymlink + } + // Open existing file. + if mustCreate { + return nil, syserror.EEXIST + } + return child.open(ctx, rp, opts.Flags, false) +} + +func (d *dentry) open(ctx context.Context, rp *vfs.ResolvingPath, flags uint32, afterCreate bool) (*vfs.FileDescription, error) { + ats := vfs.AccessTypesForOpenFlags(flags) + if !afterCreate { + if err := d.inode.checkPermissions(rp.Credentials(), ats, d.inode.isDir()); err != nil { + return nil, err + } + } + mnt := rp.Mount() + switch impl := d.inode.impl.(type) { + case *regularFile: + var fd regularFileFD + fd.readable = vfs.MayReadFileWithOpenFlags(flags) + fd.writable = vfs.MayWriteFileWithOpenFlags(flags) + if fd.writable { + if err := mnt.CheckBeginWrite(); err != nil { + return nil, err + } + // mnt.EndWrite() is called by regularFileFD.Release(). + } + fd.vfsfd.Init(&fd, flags, mnt, &d.vfsd, &vfs.FileDescriptionOptions{}) + if flags&linux.O_TRUNC != 0 { + impl.mu.Lock() + impl.data.Truncate(0, impl.memFile) + atomic.StoreUint64(&impl.size, 0) + impl.mu.Unlock() + } + return &fd.vfsfd, nil + case *directory: + // Can't open directories writably. + if ats&vfs.MayWrite != 0 { + return nil, syserror.EISDIR + } + var fd directoryFD + fd.vfsfd.Init(&fd, flags, mnt, &d.vfsd, &vfs.FileDescriptionOptions{}) + return &fd.vfsfd, nil + case *symlink: + // Can't open symlinks without O_PATH (which is unimplemented). + return nil, syserror.ELOOP + case *namedPipe: + return newNamedPipeFD(ctx, impl, rp, &d.vfsd, flags) + default: + panic(fmt.Sprintf("unknown inode type: %T", d.inode.impl)) + } +} + +// ReadlinkAt implements vfs.FilesystemImpl.ReadlinkAt. +func (fs *filesystem) ReadlinkAt(ctx context.Context, rp *vfs.ResolvingPath) (string, error) { + fs.mu.RLock() + defer fs.mu.RUnlock() + d, err := resolveLocked(rp) + if err != nil { + return "", err + } + symlink, ok := d.inode.impl.(*symlink) + if !ok { + return "", syserror.EINVAL + } + return symlink.target, nil +} + +// RenameAt implements vfs.FilesystemImpl.RenameAt. +func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldParentVD vfs.VirtualDentry, oldName string, opts vfs.RenameOptions) error { + if opts.Flags != 0 { + // TODO(b/145974740): Support renameat2 flags. + return syserror.EINVAL + } + + // Resolve newParent first to verify that it's on this Mount. + fs.mu.Lock() + defer fs.mu.Unlock() + newParent, err := walkParentDirLocked(rp, rp.Start().Impl().(*dentry)) + if err != nil { + return err + } + newName := rp.Component() + if newName == "." || newName == ".." { + return syserror.EBUSY + } + mnt := rp.Mount() + if mnt != oldParentVD.Mount() { + return syserror.EXDEV + } + if err := mnt.CheckBeginWrite(); err != nil { + return err + } + defer mnt.EndWrite() + + oldParent := oldParentVD.Dentry().Impl().(*dentry) + if err := oldParent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec, true /* isDir */); err != nil { + return err + } + // Call vfs.Dentry.Child() instead of stepLocked() or rp.ResolveChild(), + // because if the existing child is a symlink or mount point then we want + // to rename over it rather than follow it. + renamedVFSD := oldParent.vfsd.Child(oldName) + if renamedVFSD == nil { + return syserror.ENOENT + } + renamed := renamedVFSD.Impl().(*dentry) + if renamed.inode.isDir() { + if renamed == newParent || renamedVFSD.IsAncestorOf(&newParent.vfsd) { + return syserror.EINVAL + } + if oldParent != newParent { + // Writability is needed to change renamed's "..". + if err := renamed.inode.checkPermissions(rp.Credentials(), vfs.MayWrite, true /* isDir */); err != nil { + return err + } + } + } else { + if opts.MustBeDir || rp.MustBeDir() { + return syserror.ENOTDIR + } + } + + if err := newParent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec, true /* isDir */); err != nil { + return err + } + replacedVFSD := newParent.vfsd.Child(newName) + var replaced *dentry + if replacedVFSD != nil { + replaced = replacedVFSD.Impl().(*dentry) + if replaced.inode.isDir() { + if !renamed.inode.isDir() { + return syserror.EISDIR + } + if replaced.vfsd.HasChildren() { + return syserror.ENOTEMPTY + } + } else { + if rp.MustBeDir() { + return syserror.ENOTDIR + } + if renamed.inode.isDir() { + return syserror.ENOTDIR + } + } + } else { + if renamed.inode.isDir() && newParent.inode.nlink == maxLinks { + return syserror.EMLINK + } + } + if newParent.vfsd.IsDisowned() { + return syserror.ENOENT + } + + // Linux places this check before some of those above; we do it here for + // simplicity, under the assumption that applications are not intentionally + // doing noop renames expecting them to succeed where non-noop renames + // would fail. + if renamedVFSD == replacedVFSD { + return nil + } + vfsObj := rp.VirtualFilesystem() + oldParentDir := oldParent.inode.impl.(*directory) + newParentDir := newParent.inode.impl.(*directory) + if err := vfsObj.PrepareRenameDentry(vfs.MountNamespaceFromContext(ctx), renamedVFSD, replacedVFSD); err != nil { + return err + } + if replaced != nil { + newParentDir.childList.Remove(replaced) + if replaced.inode.isDir() { + newParent.inode.decLinksLocked() // from replaced's ".." + } + replaced.inode.decLinksLocked() + } + oldParentDir.childList.Remove(renamed) + newParentDir.childList.PushBack(renamed) + if renamed.inode.isDir() { + oldParent.inode.decLinksLocked() + newParent.inode.incLinksLocked() + } + // TODO: update timestamps and parent directory sizes + vfsObj.CommitRenameReplaceDentry(renamedVFSD, &newParent.vfsd, newName, replacedVFSD) + return nil +} + +// RmdirAt implements vfs.FilesystemImpl.RmdirAt. +func (fs *filesystem) RmdirAt(ctx context.Context, rp *vfs.ResolvingPath) error { + fs.mu.Lock() + defer fs.mu.Unlock() + parent, err := walkParentDirLocked(rp, rp.Start().Impl().(*dentry)) + if err != nil { + return err + } + if err := parent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec, true /* isDir */); err != nil { + return err + } + name := rp.Component() + if name == "." { + return syserror.EINVAL + } + if name == ".." { + return syserror.ENOTEMPTY + } + childVFSD := parent.vfsd.Child(name) + if childVFSD == nil { + return syserror.ENOENT + } + child := childVFSD.Impl().(*dentry) + if !child.inode.isDir() { + return syserror.ENOTDIR + } + if childVFSD.HasChildren() { + return syserror.ENOTEMPTY + } + mnt := rp.Mount() + if err := mnt.CheckBeginWrite(); err != nil { + return err + } + defer mnt.EndWrite() + vfsObj := rp.VirtualFilesystem() + if err := vfsObj.PrepareDeleteDentry(vfs.MountNamespaceFromContext(ctx), childVFSD); err != nil { + return err + } + parent.inode.impl.(*directory).childList.Remove(child) + parent.inode.decLinksLocked() // from child's ".." + child.inode.decLinksLocked() + vfsObj.CommitDeleteDentry(childVFSD) + return nil +} + +// SetStatAt implements vfs.FilesystemImpl.SetStatAt. +func (fs *filesystem) SetStatAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.SetStatOptions) error { + fs.mu.RLock() + defer fs.mu.RUnlock() + _, err := resolveLocked(rp) + if err != nil { + return err + } + if opts.Stat.Mask == 0 { + return nil + } + // TODO: implement inode.setStat + return syserror.EPERM +} + +// StatAt implements vfs.FilesystemImpl.StatAt. +func (fs *filesystem) StatAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.StatOptions) (linux.Statx, error) { + fs.mu.RLock() + defer fs.mu.RUnlock() + d, err := resolveLocked(rp) + if err != nil { + return linux.Statx{}, err + } + var stat linux.Statx + d.inode.statTo(&stat) + return stat, nil +} + +// StatFSAt implements vfs.FilesystemImpl.StatFSAt. +func (fs *filesystem) StatFSAt(ctx context.Context, rp *vfs.ResolvingPath) (linux.Statfs, error) { + fs.mu.RLock() + defer fs.mu.RUnlock() + _, err := resolveLocked(rp) + if err != nil { + return linux.Statfs{}, err + } + // TODO: actually implement statfs + return linux.Statfs{}, syserror.ENOSYS +} + +// SymlinkAt implements vfs.FilesystemImpl.SymlinkAt. +func (fs *filesystem) SymlinkAt(ctx context.Context, rp *vfs.ResolvingPath, target string) error { + return fs.doCreateAt(rp, false /* dir */, func(parent *dentry, name string) error { + child := fs.newDentry(fs.newSymlink(rp.Credentials(), target)) + parent.vfsd.InsertChild(&child.vfsd, name) + parent.inode.impl.(*directory).childList.PushBack(child) + return nil + }) +} + +// UnlinkAt implements vfs.FilesystemImpl.UnlinkAt. +func (fs *filesystem) UnlinkAt(ctx context.Context, rp *vfs.ResolvingPath) error { + fs.mu.Lock() + defer fs.mu.Unlock() + parent, err := walkParentDirLocked(rp, rp.Start().Impl().(*dentry)) + if err != nil { + return err + } + if err := parent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec, true /* isDir */); err != nil { + return err + } + name := rp.Component() + if name == "." || name == ".." { + return syserror.EISDIR + } + childVFSD := parent.vfsd.Child(name) + if childVFSD == nil { + return syserror.ENOENT + } + child := childVFSD.Impl().(*dentry) + if child.inode.isDir() { + return syserror.EISDIR + } + if !rp.MustBeDir() { + return syserror.ENOTDIR + } + mnt := rp.Mount() + if err := mnt.CheckBeginWrite(); err != nil { + return err + } + defer mnt.EndWrite() + vfsObj := rp.VirtualFilesystem() + if err := vfsObj.PrepareDeleteDentry(vfs.MountNamespaceFromContext(ctx), childVFSD); err != nil { + return err + } + parent.inode.impl.(*directory).childList.Remove(child) + child.inode.decLinksLocked() + vfsObj.CommitDeleteDentry(childVFSD) + return nil +} + +// ListxattrAt implements vfs.FilesystemImpl.ListxattrAt. +func (fs *filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath) ([]string, error) { + fs.mu.RLock() + defer fs.mu.RUnlock() + _, err := resolveLocked(rp) + if err != nil { + return nil, err + } + // TODO(b/127675828): support extended attributes + return nil, syserror.ENOTSUP +} + +// GetxattrAt implements vfs.FilesystemImpl.GetxattrAt. +func (fs *filesystem) GetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, name string) (string, error) { + fs.mu.RLock() + defer fs.mu.RUnlock() + _, err := resolveLocked(rp) + if err != nil { + return "", err + } + // TODO(b/127675828): support extended attributes + return "", syserror.ENOTSUP +} + +// SetxattrAt implements vfs.FilesystemImpl.SetxattrAt. +func (fs *filesystem) SetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.SetxattrOptions) error { + fs.mu.RLock() + defer fs.mu.RUnlock() + _, err := resolveLocked(rp) + if err != nil { + return err + } + // TODO(b/127675828): support extended attributes + return syserror.ENOTSUP +} + +// RemovexattrAt implements vfs.FilesystemImpl.RemovexattrAt. +func (fs *filesystem) RemovexattrAt(ctx context.Context, rp *vfs.ResolvingPath, name string) error { + fs.mu.RLock() + defer fs.mu.RUnlock() + _, err := resolveLocked(rp) + if err != nil { + return err + } + // TODO(b/127675828): support extended attributes + return syserror.ENOTSUP +} + +// PrependPath implements vfs.FilesystemImpl.PrependPath. +func (fs *filesystem) PrependPath(ctx context.Context, vfsroot, vd vfs.VirtualDentry, b *fspath.Builder) error { + fs.mu.RLock() + defer fs.mu.RUnlock() + return vfs.GenericPrependPath(vfsroot, vd, b) +} -- cgit v1.2.3 From d6fb1ec6c7c76040dd20e915b32f9ed795ae7077 Mon Sep 17 00:00:00 2001 From: Nicolas Lacasse Date: Wed, 15 Jan 2020 16:31:24 -0800 Subject: Add timestamps to VFS2 tmpfs, and implement some of SetStat. PiperOrigin-RevId: 289962040 --- pkg/abi/linux/time.go | 13 ++ pkg/sentry/fsimpl/tmpfs/BUILD | 2 + pkg/sentry/fsimpl/tmpfs/filesystem.go | 16 +- pkg/sentry/fsimpl/tmpfs/regular_file_test.go | 129 ++++++++++++--- pkg/sentry/fsimpl/tmpfs/stat_test.go | 232 +++++++++++++++++++++++++++ pkg/sentry/fsimpl/tmpfs/tmpfs.go | 72 +++++++-- 6 files changed, 425 insertions(+), 39 deletions(-) create mode 100644 pkg/sentry/fsimpl/tmpfs/stat_test.go (limited to 'pkg/sentry/fsimpl/tmpfs/filesystem.go') diff --git a/pkg/abi/linux/time.go b/pkg/abi/linux/time.go index 546668bca..5c5a58cd4 100644 --- a/pkg/abi/linux/time.go +++ b/pkg/abi/linux/time.go @@ -234,6 +234,19 @@ type StatxTimestamp struct { _ int32 } +// ToNsec returns the nanosecond representation. +func (sxts StatxTimestamp) ToNsec() int64 { + return int64(sxts.Sec)*1e9 + int64(sxts.Nsec) +} + +// ToNsecCapped returns the safe nanosecond representation. +func (sxts StatxTimestamp) ToNsecCapped() int64 { + if sxts.Sec > maxSecInDuration { + return math.MaxInt64 + } + return sxts.ToNsec() +} + // NsecToStatxTimestamp translates nanoseconds to StatxTimestamp. func NsecToStatxTimestamp(nsec int64) (ts StatxTimestamp) { return StatxTimestamp{ diff --git a/pkg/sentry/fsimpl/tmpfs/BUILD b/pkg/sentry/fsimpl/tmpfs/BUILD index 82f5c2f41..7601c7c04 100644 --- a/pkg/sentry/fsimpl/tmpfs/BUILD +++ b/pkg/sentry/fsimpl/tmpfs/BUILD @@ -40,6 +40,7 @@ go_library( "//pkg/sentry/kernel", "//pkg/sentry/kernel/auth", "//pkg/sentry/kernel/pipe", + "//pkg/sentry/kernel/time", "//pkg/sentry/memmap", "//pkg/sentry/pgalloc", "//pkg/sentry/platform", @@ -77,6 +78,7 @@ go_test( srcs = [ "pipe_test.go", "regular_file_test.go", + "stat_test.go", ], embed = [":tmpfs"], deps = [ diff --git a/pkg/sentry/fsimpl/tmpfs/filesystem.go b/pkg/sentry/fsimpl/tmpfs/filesystem.go index 26979729e..4cd7e9aea 100644 --- a/pkg/sentry/fsimpl/tmpfs/filesystem.go +++ b/pkg/sentry/fsimpl/tmpfs/filesystem.go @@ -56,7 +56,8 @@ afterSymlink: } next := nextVFSD.Impl().(*dentry) if symlink, ok := next.inode.impl.(*symlink); ok && rp.ShouldFollowSymlink() { - // TODO: symlink traversals update access time + // TODO(gvisor.dev/issues/1197): Symlink traversals updates + // access time. if err := rp.HandleSymlink(symlink.target); err != nil { return nil, err } @@ -501,7 +502,8 @@ func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa oldParent.inode.decLinksLocked() newParent.inode.incLinksLocked() } - // TODO: update timestamps and parent directory sizes + // TODO(gvisor.dev/issues/1197): Update timestamps and parent directory + // sizes. vfsObj.CommitRenameReplaceDentry(renamedVFSD, &newParent.vfsd, newName, replacedVFSD) return nil } @@ -555,15 +557,11 @@ func (fs *filesystem) RmdirAt(ctx context.Context, rp *vfs.ResolvingPath) error func (fs *filesystem) SetStatAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.SetStatOptions) error { fs.mu.RLock() defer fs.mu.RUnlock() - _, err := resolveLocked(rp) + d, err := resolveLocked(rp) if err != nil { return err } - if opts.Stat.Mask == 0 { - return nil - } - // TODO: implement inode.setStat - return syserror.EPERM + return d.inode.setStat(opts.Stat) } // StatAt implements vfs.FilesystemImpl.StatAt. @@ -587,7 +585,7 @@ func (fs *filesystem) StatFSAt(ctx context.Context, rp *vfs.ResolvingPath) (linu if err != nil { return linux.Statfs{}, err } - // TODO: actually implement statfs + // TODO(gvisor.dev/issues/1197): Actually implement statfs. return linux.Statfs{}, syserror.ENOSYS } diff --git a/pkg/sentry/fsimpl/tmpfs/regular_file_test.go b/pkg/sentry/fsimpl/tmpfs/regular_file_test.go index 3731c5b6f..7b0a962f0 100644 --- a/pkg/sentry/fsimpl/tmpfs/regular_file_test.go +++ b/pkg/sentry/fsimpl/tmpfs/regular_file_test.go @@ -18,6 +18,7 @@ import ( "bytes" "fmt" "io" + "sync/atomic" "testing" "gvisor.dev/gvisor/pkg/abi/linux" @@ -29,10 +30,12 @@ import ( "gvisor.dev/gvisor/pkg/sentry/vfs" ) -// newFileFD creates a new file in a new tmpfs mount, and returns the FD. If -// the returned err is not nil, then cleanup should be called when the FD is no -// longer needed. -func newFileFD(ctx context.Context, filename string) (*vfs.FileDescription, func(), error) { +// nextFileID is used to generate unique file names. +var nextFileID int64 + +// newTmpfsRoot creates a new tmpfs mount, and returns the root. If the error +// is not nil, then cleanup should be called when the root is no longer needed. +func newTmpfsRoot(ctx context.Context) (*vfs.VirtualFilesystem, vfs.VirtualDentry, func(), error) { creds := auth.CredentialsFromContext(ctx) vfsObj := vfs.New() @@ -41,36 +44,124 @@ func newFileFD(ctx context.Context, filename string) (*vfs.FileDescription, func }) mntns, err := vfsObj.NewMountNamespace(ctx, creds, "", "tmpfs", &vfs.GetFilesystemOptions{}) if err != nil { - return nil, nil, fmt.Errorf("failed to create tmpfs root mount: %v", err) + return nil, vfs.VirtualDentry{}, nil, fmt.Errorf("failed to create tmpfs root mount: %v", err) } root := mntns.Root() + return vfsObj, root, func() { + root.DecRef() + mntns.DecRef(vfsObj) + }, nil +} + +// newFileFD creates a new file in a new tmpfs mount, and returns the FD. If +// the returned err is not nil, then cleanup should be called when the FD is no +// longer needed. +func newFileFD(ctx context.Context, mode linux.FileMode) (*vfs.FileDescription, func(), error) { + creds := auth.CredentialsFromContext(ctx) + vfsObj, root, cleanup, err := newTmpfsRoot(ctx) + if err != nil { + return nil, nil, err + } + + filename := fmt.Sprintf("tmpfs-test-file-%d", atomic.AddInt64(&nextFileID, 1)) // Create the file that will be write/read. fd, err := vfsObj.OpenAt(ctx, creds, &vfs.PathOperation{ - Root: root, - Start: root, - Path: fspath.Parse(filename), - FollowFinalSymlink: true, + Root: root, + Start: root, + Path: fspath.Parse(filename), }, &vfs.OpenOptions{ Flags: linux.O_RDWR | linux.O_CREAT | linux.O_EXCL, - Mode: 0644, + Mode: linux.ModeRegular | mode, }) if err != nil { - root.DecRef() - mntns.DecRef(vfsObj) + cleanup() return nil, nil, fmt.Errorf("failed to create file %q: %v", filename, err) } - return fd, func() { - root.DecRef() - mntns.DecRef(vfsObj) - }, nil + return fd, cleanup, nil +} + +// newDirFD is like newFileFD, but for directories. +func newDirFD(ctx context.Context, mode linux.FileMode) (*vfs.FileDescription, func(), error) { + creds := auth.CredentialsFromContext(ctx) + vfsObj, root, cleanup, err := newTmpfsRoot(ctx) + if err != nil { + return nil, nil, err + } + + dirname := fmt.Sprintf("tmpfs-test-dir-%d", atomic.AddInt64(&nextFileID, 1)) + + // Create the dir. + if err := vfsObj.MkdirAt(ctx, creds, &vfs.PathOperation{ + Root: root, + Start: root, + Path: fspath.Parse(dirname), + }, &vfs.MkdirOptions{ + Mode: linux.ModeDirectory | mode, + }); err != nil { + cleanup() + return nil, nil, fmt.Errorf("failed to create directory %q: %v", dirname, err) + } + + // Open the dir and return it. + fd, err := vfsObj.OpenAt(ctx, creds, &vfs.PathOperation{ + Root: root, + Start: root, + Path: fspath.Parse(dirname), + }, &vfs.OpenOptions{ + Flags: linux.O_RDONLY | linux.O_DIRECTORY, + }) + if err != nil { + cleanup() + return nil, nil, fmt.Errorf("failed to open directory %q: %v", dirname, err) + } + + return fd, cleanup, nil +} + +// newPipeFD is like newFileFD, but for pipes. +func newPipeFD(ctx context.Context, mode linux.FileMode) (*vfs.FileDescription, func(), error) { + creds := auth.CredentialsFromContext(ctx) + vfsObj, root, cleanup, err := newTmpfsRoot(ctx) + if err != nil { + return nil, nil, err + } + + pipename := fmt.Sprintf("tmpfs-test-pipe-%d", atomic.AddInt64(&nextFileID, 1)) + + // Create the pipe. + if err := vfsObj.MknodAt(ctx, creds, &vfs.PathOperation{ + Root: root, + Start: root, + Path: fspath.Parse(pipename), + }, &vfs.MknodOptions{ + Mode: linux.ModeNamedPipe | mode, + }); err != nil { + cleanup() + return nil, nil, fmt.Errorf("failed to create pipe %q: %v", pipename, err) + } + + // Open the pipe and return it. + fd, err := vfsObj.OpenAt(ctx, creds, &vfs.PathOperation{ + Root: root, + Start: root, + Path: fspath.Parse(pipename), + }, &vfs.OpenOptions{ + Flags: linux.O_RDWR, + }) + if err != nil { + cleanup() + return nil, nil, fmt.Errorf("failed to open pipe %q: %v", pipename, err) + } + + return fd, cleanup, nil } // Test that we can write some data to a file and read it back.` func TestSimpleWriteRead(t *testing.T) { ctx := contexttest.Context(t) - fd, cleanup, err := newFileFD(ctx, "simpleReadWrite") + fd, cleanup, err := newFileFD(ctx, 0644) if err != nil { t.Fatal(err) } @@ -116,7 +207,7 @@ func TestSimpleWriteRead(t *testing.T) { func TestPWrite(t *testing.T) { ctx := contexttest.Context(t) - fd, cleanup, err := newFileFD(ctx, "PRead") + fd, cleanup, err := newFileFD(ctx, 0644) if err != nil { t.Fatal(err) } @@ -171,7 +262,7 @@ func TestPWrite(t *testing.T) { func TestPRead(t *testing.T) { ctx := contexttest.Context(t) - fd, cleanup, err := newFileFD(ctx, "PRead") + fd, cleanup, err := newFileFD(ctx, 0644) if err != nil { t.Fatal(err) } diff --git a/pkg/sentry/fsimpl/tmpfs/stat_test.go b/pkg/sentry/fsimpl/tmpfs/stat_test.go new file mode 100644 index 000000000..ebe035dee --- /dev/null +++ b/pkg/sentry/fsimpl/tmpfs/stat_test.go @@ -0,0 +1,232 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package tmpfs + +import ( + "fmt" + "testing" + + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/kernel/auth" + "gvisor.dev/gvisor/pkg/sentry/kernel/contexttest" + "gvisor.dev/gvisor/pkg/sentry/vfs" +) + +func TestStatAfterCreate(t *testing.T) { + ctx := contexttest.Context(t) + mode := linux.FileMode(0644) + + // Run with different file types. + // TODO(gvisor.dev/issues/1197): Also test symlinks and sockets. + for _, typ := range []string{"file", "dir", "pipe"} { + t.Run(fmt.Sprintf("type=%q", typ), func(t *testing.T) { + var ( + fd *vfs.FileDescription + cleanup func() + err error + ) + switch typ { + case "file": + fd, cleanup, err = newFileFD(ctx, mode) + case "dir": + fd, cleanup, err = newDirFD(ctx, mode) + case "pipe": + fd, cleanup, err = newPipeFD(ctx, mode) + default: + panic(fmt.Sprintf("unknown typ %q", typ)) + } + if err != nil { + t.Fatal(err) + } + defer cleanup() + + got, err := fd.Stat(ctx, vfs.StatOptions{}) + if err != nil { + t.Fatalf("Stat failed: %v", err) + } + + // Atime, Ctime, Mtime should all be current time (non-zero). + atime, ctime, mtime := got.Atime.ToNsec(), got.Ctime.ToNsec(), got.Mtime.ToNsec() + if atime != ctime || ctime != mtime { + t.Errorf("got atime=%d ctime=%d mtime=%d, wanted equal values", atime, ctime, mtime) + } + if atime == 0 { + t.Errorf("got atime=%d, want non-zero", atime) + } + + // Btime should be 0, as it is not set by tmpfs. + if btime := got.Btime.ToNsec(); btime != 0 { + t.Errorf("got btime %d, want 0", got.Btime.ToNsec()) + } + + // Size should be 0. + if got.Size != 0 { + t.Errorf("got size %d, want 0", got.Size) + } + + // Nlink should be 1 for files, 2 for dirs. + wantNlink := uint32(1) + if typ == "dir" { + wantNlink = 2 + } + if got.Nlink != wantNlink { + t.Errorf("got nlink %d, want %d", got.Nlink, wantNlink) + } + + // UID and GID are set from context creds. + creds := auth.CredentialsFromContext(ctx) + if got.UID != uint32(creds.EffectiveKUID) { + t.Errorf("got uid %d, want %d", got.UID, uint32(creds.EffectiveKUID)) + } + if got.GID != uint32(creds.EffectiveKGID) { + t.Errorf("got gid %d, want %d", got.GID, uint32(creds.EffectiveKGID)) + } + + // Mode. + wantMode := uint16(mode) + switch typ { + case "file": + wantMode |= linux.S_IFREG + case "dir": + wantMode |= linux.S_IFDIR + case "pipe": + wantMode |= linux.S_IFIFO + default: + panic(fmt.Sprintf("unknown typ %q", typ)) + } + + if got.Mode != wantMode { + t.Errorf("got mode %x, want %x", got.Mode, wantMode) + } + + // Ino. + if got.Ino == 0 { + t.Errorf("got ino %d, want not 0", got.Ino) + } + }) + } +} + +func TestSetStatAtime(t *testing.T) { + ctx := contexttest.Context(t) + fd, cleanup, err := newFileFD(ctx, 0644) + if err != nil { + t.Fatal(err) + } + defer cleanup() + + allStatOptions := vfs.StatOptions{Mask: linux.STATX_ALL} + + // Get initial stat. + initialStat, err := fd.Stat(ctx, allStatOptions) + if err != nil { + t.Fatalf("Stat failed: %v", err) + } + + // Set atime, but without the mask. + if err := fd.SetStat(ctx, vfs.SetStatOptions{Stat: linux.Statx{ + Mask: 0, + Atime: linux.NsecToStatxTimestamp(100), + }}); err != nil { + t.Errorf("SetStat atime without mask failed: %v") + } + // Atime should be unchanged. + if gotStat, err := fd.Stat(ctx, allStatOptions); err != nil { + t.Errorf("Stat got error: %v", err) + } else if gotStat.Atime != initialStat.Atime { + t.Errorf("Stat got atime %d, want %d", gotStat.Atime, initialStat.Atime) + } + + // Set atime, this time included in the mask. + setStat := linux.Statx{ + Mask: linux.STATX_ATIME, + Atime: linux.NsecToStatxTimestamp(100), + } + if err := fd.SetStat(ctx, vfs.SetStatOptions{Stat: setStat}); err != nil { + t.Errorf("SetStat atime with mask failed: %v") + } + if gotStat, err := fd.Stat(ctx, allStatOptions); err != nil { + t.Errorf("Stat got error: %v", err) + } else if gotStat.Atime != setStat.Atime { + t.Errorf("Stat got atime %d, want %d", gotStat.Atime, setStat.Atime) + } +} + +func TestSetStat(t *testing.T) { + ctx := contexttest.Context(t) + mode := linux.FileMode(0644) + + // Run with different file types. + // TODO(gvisor.dev/issues/1197): Also test symlinks and sockets. + for _, typ := range []string{"file", "dir", "pipe"} { + t.Run(fmt.Sprintf("type=%q", typ), func(t *testing.T) { + var ( + fd *vfs.FileDescription + cleanup func() + err error + ) + switch typ { + case "file": + fd, cleanup, err = newFileFD(ctx, mode) + case "dir": + fd, cleanup, err = newDirFD(ctx, mode) + case "pipe": + fd, cleanup, err = newPipeFD(ctx, mode) + default: + panic(fmt.Sprintf("unknown typ %q", typ)) + } + if err != nil { + t.Fatal(err) + } + defer cleanup() + + allStatOptions := vfs.StatOptions{Mask: linux.STATX_ALL} + + // Get initial stat. + initialStat, err := fd.Stat(ctx, allStatOptions) + if err != nil { + t.Fatalf("Stat failed: %v", err) + } + + // Set atime, but without the mask. + if err := fd.SetStat(ctx, vfs.SetStatOptions{Stat: linux.Statx{ + Mask: 0, + Atime: linux.NsecToStatxTimestamp(100), + }}); err != nil { + t.Errorf("SetStat atime without mask failed: %v") + } + // Atime should be unchanged. + if gotStat, err := fd.Stat(ctx, allStatOptions); err != nil { + t.Errorf("Stat got error: %v", err) + } else if gotStat.Atime != initialStat.Atime { + t.Errorf("Stat got atime %d, want %d", gotStat.Atime, initialStat.Atime) + } + + // Set atime, this time included in the mask. + setStat := linux.Statx{ + Mask: linux.STATX_ATIME, + Atime: linux.NsecToStatxTimestamp(100), + } + if err := fd.SetStat(ctx, vfs.SetStatOptions{Stat: setStat}); err != nil { + t.Errorf("SetStat atime with mask failed: %v") + } + if gotStat, err := fd.Stat(ctx, allStatOptions); err != nil { + t.Errorf("Stat got error: %v", err) + } else if gotStat.Atime != setStat.Atime { + t.Errorf("Stat got atime %d, want %d", gotStat.Atime, setStat.Atime) + } + }) + } +} diff --git a/pkg/sentry/fsimpl/tmpfs/tmpfs.go b/pkg/sentry/fsimpl/tmpfs/tmpfs.go index 701826f90..d6960ee47 100644 --- a/pkg/sentry/fsimpl/tmpfs/tmpfs.go +++ b/pkg/sentry/fsimpl/tmpfs/tmpfs.go @@ -31,10 +31,10 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" + "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/pgalloc" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/sync" - "gvisor.dev/gvisor/pkg/syserror" ) // FilesystemType implements vfs.FilesystemType. @@ -47,6 +47,9 @@ type filesystem struct { // memFile is used to allocate pages to for regular files. memFile *pgalloc.MemoryFile + // clock is a realtime clock used to set timestamps in file operations. + clock time.Clock + // mu serializes changes to the Dentry tree. mu sync.RWMutex @@ -59,8 +62,10 @@ func (fstype FilesystemType) GetFilesystem(ctx context.Context, vfsObj *vfs.Virt if memFileProvider == nil { panic("MemoryFileProviderFromContext returned nil") } + clock := time.RealtimeClockFromContext(ctx) fs := filesystem{ memFile: memFileProvider.MemoryFile(), + clock: clock, } fs.vfsfs.Init(vfsObj, &fs) root := fs.newDentry(fs.newDirectory(creds, 01777)) @@ -126,26 +131,36 @@ type inode struct { // filesystem.RmdirAt() drops the reference. refs int64 - // Inode metadata; protected by mu and accessed using atomic memory - // operations unless otherwise specified. - mu sync.RWMutex + // Inode metadata. Writing multiple fields atomically requires holding + // mu, othewise atomic operations can be used. + mu sync.Mutex mode uint32 // excluding file type bits, which are based on impl nlink uint32 // protected by filesystem.mu instead of inode.mu uid uint32 // auth.KUID, but stored as raw uint32 for sync/atomic gid uint32 // auth.KGID, but ... ino uint64 // immutable + // Linux's tmpfs has no concept of btime. + atime int64 // nanoseconds + ctime int64 // nanoseconds + mtime int64 // nanoseconds + impl interface{} // immutable } const maxLinks = math.MaxUint32 func (i *inode) init(impl interface{}, fs *filesystem, creds *auth.Credentials, mode linux.FileMode) { + now := fs.clock.Now().Nanoseconds() i.refs = 1 i.mode = uint32(mode) i.uid = uint32(creds.EffectiveKUID) i.gid = uint32(creds.EffectiveKGID) i.ino = atomic.AddUint64(&fs.nextInoMinusOne, 1) + // Tmpfs creation sets atime, ctime, and mtime to current time. + i.atime = now + i.ctime = now + i.mtime = now // i.nlink initialized by caller i.impl = impl } @@ -213,15 +228,24 @@ func (i *inode) checkPermissions(creds *auth.Credentials, ats vfs.AccessTypes, i // Go won't inline this function, and returning linux.Statx (which is quite // big) means spending a lot of time in runtime.duffcopy(), so instead it's an // output parameter. +// +// Note that Linux does not guarantee to return consistent data (in the case of +// a concurrent modification), so we do not require holding inode.mu. func (i *inode) statTo(stat *linux.Statx) { - stat.Mask = linux.STATX_TYPE | linux.STATX_MODE | linux.STATX_NLINK | linux.STATX_UID | linux.STATX_GID | linux.STATX_INO + stat.Mask = linux.STATX_TYPE | linux.STATX_MODE | linux.STATX_NLINK | + linux.STATX_UID | linux.STATX_GID | linux.STATX_INO | linux.STATX_ATIME | + linux.STATX_BTIME | linux.STATX_CTIME | linux.STATX_MTIME stat.Blksize = 1 // usermem.PageSize in tmpfs stat.Nlink = atomic.LoadUint32(&i.nlink) stat.UID = atomic.LoadUint32(&i.uid) stat.GID = atomic.LoadUint32(&i.gid) stat.Mode = uint16(atomic.LoadUint32(&i.mode)) stat.Ino = i.ino - // TODO: device number + // Linux's tmpfs has no concept of btime, so zero-value is returned. + stat.Atime = linux.NsecToStatxTimestamp(i.atime) + stat.Ctime = linux.NsecToStatxTimestamp(i.ctime) + stat.Mtime = linux.NsecToStatxTimestamp(i.mtime) + // TODO(gvisor.dev/issues/1197): Device number. switch impl := i.impl.(type) { case *regularFile: stat.Mode |= linux.S_IFREG @@ -245,6 +269,36 @@ func (i *inode) statTo(stat *linux.Statx) { } } +func (i *inode) setStat(stat linux.Statx) error { + // TODO(gvisor.dev/issues/1197): Handle stat.Size by growing/shrinking + // the file. + if stat.Mask == 0 { + return nil + } + i.mu.Lock() + mask := stat.Mask + if mask&linux.STATX_MODE != 0 { + atomic.StoreUint32(&i.mode, uint32(stat.Mode)) + } + if mask&linux.STATX_UID != 0 { + atomic.StoreUint32(&i.uid, stat.UID) + } + if mask&linux.STATX_GID != 0 { + atomic.StoreUint32(&i.gid, stat.GID) + } + if mask&linux.STATX_ATIME != 0 { + atomic.StoreInt64(&i.atime, stat.Atime.ToNsecCapped()) + } + if mask&linux.STATX_CTIME != 0 { + atomic.StoreInt64(&i.ctime, stat.Ctime.ToNsecCapped()) + } + if mask&linux.STATX_MTIME != 0 { + atomic.StoreInt64(&i.mtime, stat.Mtime.ToNsecCapped()) + } + i.mu.Unlock() + return nil +} + // allocatedBlocksForSize returns the number of 512B blocks needed to // accommodate the given size in bytes, as appropriate for struct // stat::st_blocks and struct statx::stx_blocks. (Note that this 512B block @@ -291,9 +345,5 @@ func (fd *fileDescription) Stat(ctx context.Context, opts vfs.StatOptions) (linu // SetStat implements vfs.FileDescriptionImpl.SetStat. func (fd *fileDescription) SetStat(ctx context.Context, opts vfs.SetStatOptions) error { - if opts.Stat.Mask == 0 { - return nil - } - // TODO: implement inode.setStat - return syserror.EPERM + return fd.inode().setStat(opts.Stat) } -- cgit v1.2.3 From 5ab1213a6c405071546c783d6d93b4e9af52842e Mon Sep 17 00:00:00 2001 From: Jamie Liu Date: Wed, 22 Jan 2020 12:27:16 -0800 Subject: Move VFS2 handling of FD readability/writability to vfs.FileDescription. PiperOrigin-RevId: 291006713 --- pkg/sentry/fsimpl/ext/inode.go | 8 +++- pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go | 11 +++-- pkg/sentry/fsimpl/kernfs/fd_impl_util.go | 11 ++++- pkg/sentry/fsimpl/kernfs/kernfs_test.go | 18 +++++-- pkg/sentry/fsimpl/tmpfs/filesystem.go | 15 ++---- pkg/sentry/fsimpl/tmpfs/named_pipe.go | 5 +- pkg/sentry/fsimpl/tmpfs/regular_file.go | 14 +----- pkg/sentry/kernel/pipe/vfs.go | 12 ++--- pkg/sentry/vfs/file_description.go | 66 ++++++++++++++++++++++++-- pkg/sentry/vfs/permissions.go | 5 +- 10 files changed, 111 insertions(+), 54 deletions(-) (limited to 'pkg/sentry/fsimpl/tmpfs/filesystem.go') diff --git a/pkg/sentry/fsimpl/ext/inode.go b/pkg/sentry/fsimpl/ext/inode.go index 8608805bf..191b39970 100644 --- a/pkg/sentry/fsimpl/ext/inode.go +++ b/pkg/sentry/fsimpl/ext/inode.go @@ -157,7 +157,9 @@ func (in *inode) open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, flags uint32) (*v switch in.impl.(type) { case *regularFile: var fd regularFileFD - fd.vfsfd.Init(&fd, flags, mnt, vfsd, &vfs.FileDescriptionOptions{}) + if err := fd.vfsfd.Init(&fd, flags, mnt, vfsd, &vfs.FileDescriptionOptions{}); err != nil { + return nil, err + } return &fd.vfsfd, nil case *directory: // Can't open directories writably. This check is not necessary for a read @@ -166,7 +168,9 @@ func (in *inode) open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, flags uint32) (*v return nil, syserror.EISDIR } var fd directoryFD - fd.vfsfd.Init(&fd, flags, mnt, vfsd, &vfs.FileDescriptionOptions{}) + if err := fd.vfsfd.Init(&fd, flags, mnt, vfsd, &vfs.FileDescriptionOptions{}); err != nil { + return nil, err + } return &fd.vfsfd, nil case *symlink: if flags&linux.O_PATH == 0 { diff --git a/pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go b/pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go index 606ca692d..75624e0b1 100644 --- a/pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go +++ b/pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go @@ -55,7 +55,9 @@ func (f *DynamicBytesFile) Init(creds *auth.Credentials, ino uint64, data vfs.Dy // Open implements Inode.Open. func (f *DynamicBytesFile) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, flags uint32) (*vfs.FileDescription, error) { fd := &DynamicBytesFD{} - fd.Init(rp.Mount(), vfsd, f.data, flags) + if err := fd.Init(rp.Mount(), vfsd, f.data, flags); err != nil { + return nil, err + } return &fd.vfsfd, nil } @@ -80,10 +82,13 @@ type DynamicBytesFD struct { } // Init initializes a DynamicBytesFD. -func (fd *DynamicBytesFD) Init(m *vfs.Mount, d *vfs.Dentry, data vfs.DynamicBytesSource, flags uint32) { +func (fd *DynamicBytesFD) Init(m *vfs.Mount, d *vfs.Dentry, data vfs.DynamicBytesSource, flags uint32) error { + if err := fd.vfsfd.Init(fd, flags, m, d, &vfs.FileDescriptionOptions{}); err != nil { + return err + } fd.inode = d.Impl().(*Dentry).inode fd.SetDataSource(data) - fd.vfsfd.Init(fd, flags, m, d, &vfs.FileDescriptionOptions{}) + return nil } // Seek implements vfs.FileDescriptionImpl.Seek. diff --git a/pkg/sentry/fsimpl/kernfs/fd_impl_util.go b/pkg/sentry/fsimpl/kernfs/fd_impl_util.go index bcf069b5f..5fa1fa67b 100644 --- a/pkg/sentry/fsimpl/kernfs/fd_impl_util.go +++ b/pkg/sentry/fsimpl/kernfs/fd_impl_util.go @@ -43,9 +43,16 @@ type GenericDirectoryFD struct { } // Init initializes a GenericDirectoryFD. -func (fd *GenericDirectoryFD) Init(m *vfs.Mount, d *vfs.Dentry, children *OrderedChildren, flags uint32) { +func (fd *GenericDirectoryFD) Init(m *vfs.Mount, d *vfs.Dentry, children *OrderedChildren, flags uint32) error { + if vfs.AccessTypesForOpenFlags(flags)&vfs.MayWrite != 0 { + // Can't open directories for writing. + return syserror.EISDIR + } + if err := fd.vfsfd.Init(fd, flags, m, d, &vfs.FileDescriptionOptions{}); err != nil { + return err + } fd.children = children - fd.vfsfd.Init(fd, flags, m, d, &vfs.FileDescriptionOptions{}) + return nil } // VFSFileDescription returns a pointer to the vfs.FileDescription representing diff --git a/pkg/sentry/fsimpl/kernfs/kernfs_test.go b/pkg/sentry/fsimpl/kernfs/kernfs_test.go index a5fdfbde5..aa3fe76ee 100644 --- a/pkg/sentry/fsimpl/kernfs/kernfs_test.go +++ b/pkg/sentry/fsimpl/kernfs/kernfs_test.go @@ -115,7 +115,9 @@ func (fs *filesystem) newReadonlyDir(creds *auth.Credentials, mode linux.FileMod func (d *readonlyDir) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, flags uint32) (*vfs.FileDescription, error) { fd := &kernfs.GenericDirectoryFD{} - fd.Init(rp.Mount(), vfsd, &d.OrderedChildren, flags) + if err := fd.Init(rp.Mount(), vfsd, &d.OrderedChildren, flags); err != nil { + return nil, err + } return fd.VFSFileDescription(), nil } @@ -225,7 +227,9 @@ func TestReadStaticFile(t *testing.T) { defer sys.Destroy() pop := sys.PathOpAtRoot("file1") - fd, err := sys.VFS.OpenAt(sys.Ctx, sys.Creds, &pop, &vfs.OpenOptions{}) + fd, err := sys.VFS.OpenAt(sys.Ctx, sys.Creds, &pop, &vfs.OpenOptions{ + Flags: linux.O_RDONLY, + }) if err != nil { t.Fatalf("OpenAt for PathOperation %+v failed: %v", pop, err) } @@ -258,7 +262,9 @@ func TestCreateNewFileInStaticDir(t *testing.T) { // Close the file. The file should persist. fd.DecRef() - fd, err = sys.VFS.OpenAt(sys.Ctx, sys.Creds, &pop, &vfs.OpenOptions{}) + fd, err = sys.VFS.OpenAt(sys.Ctx, sys.Creds, &pop, &vfs.OpenOptions{ + Flags: linux.O_RDONLY, + }) if err != nil { t.Fatalf("OpenAt(pop:%+v) = %+v failed: %v", pop, fd, err) } @@ -272,7 +278,9 @@ func TestDirFDReadWrite(t *testing.T) { defer sys.Destroy() pop := sys.PathOpAtRoot("/") - fd, err := sys.VFS.OpenAt(sys.Ctx, sys.Creds, &pop, &vfs.OpenOptions{}) + fd, err := sys.VFS.OpenAt(sys.Ctx, sys.Creds, &pop, &vfs.OpenOptions{ + Flags: linux.O_RDONLY, + }) if err != nil { t.Fatalf("OpenAt for PathOperation %+v failed: %v", pop, err) } @@ -282,7 +290,7 @@ func TestDirFDReadWrite(t *testing.T) { if _, err := fd.Read(sys.Ctx, usermem.BytesIOSequence([]byte{}), vfs.ReadOptions{}); err != syserror.EISDIR { t.Fatalf("Read for directory FD failed with unexpected error: %v", err) } - if _, err := fd.Write(sys.Ctx, usermem.BytesIOSequence([]byte{}), vfs.WriteOptions{}); err != syserror.EISDIR { + if _, err := fd.Write(sys.Ctx, usermem.BytesIOSequence([]byte{}), vfs.WriteOptions{}); err != syserror.EBADF { t.Fatalf("Write for directory FD failed with unexpected error: %v", err) } } diff --git a/pkg/sentry/fsimpl/tmpfs/filesystem.go b/pkg/sentry/fsimpl/tmpfs/filesystem.go index 4cd7e9aea..a9f66a42a 100644 --- a/pkg/sentry/fsimpl/tmpfs/filesystem.go +++ b/pkg/sentry/fsimpl/tmpfs/filesystem.go @@ -337,19 +337,12 @@ func (d *dentry) open(ctx context.Context, rp *vfs.ResolvingPath, flags uint32, return nil, err } } - mnt := rp.Mount() switch impl := d.inode.impl.(type) { case *regularFile: var fd regularFileFD - fd.readable = vfs.MayReadFileWithOpenFlags(flags) - fd.writable = vfs.MayWriteFileWithOpenFlags(flags) - if fd.writable { - if err := mnt.CheckBeginWrite(); err != nil { - return nil, err - } - // mnt.EndWrite() is called by regularFileFD.Release(). + if err := fd.vfsfd.Init(&fd, flags, rp.Mount(), &d.vfsd, &vfs.FileDescriptionOptions{}); err != nil { + return nil, err } - fd.vfsfd.Init(&fd, flags, mnt, &d.vfsd, &vfs.FileDescriptionOptions{}) if flags&linux.O_TRUNC != 0 { impl.mu.Lock() impl.data.Truncate(0, impl.memFile) @@ -363,7 +356,9 @@ func (d *dentry) open(ctx context.Context, rp *vfs.ResolvingPath, flags uint32, return nil, syserror.EISDIR } var fd directoryFD - fd.vfsfd.Init(&fd, flags, mnt, &d.vfsd, &vfs.FileDescriptionOptions{}) + if err := fd.vfsfd.Init(&fd, flags, rp.Mount(), &d.vfsd, &vfs.FileDescriptionOptions{}); err != nil { + return nil, err + } return &fd.vfsfd, nil case *symlink: // Can't open symlinks without O_PATH (which is unimplemented). diff --git a/pkg/sentry/fsimpl/tmpfs/named_pipe.go b/pkg/sentry/fsimpl/tmpfs/named_pipe.go index 40bde54de..482aabd52 100644 --- a/pkg/sentry/fsimpl/tmpfs/named_pipe.go +++ b/pkg/sentry/fsimpl/tmpfs/named_pipe.go @@ -50,11 +50,10 @@ type namedPipeFD struct { func newNamedPipeFD(ctx context.Context, np *namedPipe, rp *vfs.ResolvingPath, vfsd *vfs.Dentry, flags uint32) (*vfs.FileDescription, error) { var err error var fd namedPipeFD - fd.VFSPipeFD, err = np.pipe.NewVFSPipeFD(ctx, rp, vfsd, &fd.vfsfd, flags) + fd.VFSPipeFD, err = np.pipe.NewVFSPipeFD(ctx, vfsd, &fd.vfsfd, flags) if err != nil { return nil, err } - mnt := rp.Mount() - fd.vfsfd.Init(&fd, flags, mnt, vfsd, &vfs.FileDescriptionOptions{}) + fd.vfsfd.Init(&fd, flags, rp.Mount(), vfsd, &vfs.FileDescriptionOptions{}) return &fd.vfsfd, nil } diff --git a/pkg/sentry/fsimpl/tmpfs/regular_file.go b/pkg/sentry/fsimpl/tmpfs/regular_file.go index 5fa70cc6d..7c633c1b0 100644 --- a/pkg/sentry/fsimpl/tmpfs/regular_file.go +++ b/pkg/sentry/fsimpl/tmpfs/regular_file.go @@ -101,10 +101,6 @@ func (rf *regularFile) truncate(size uint64) (bool, error) { type regularFileFD struct { fileDescription - // These are immutable. - readable bool - writable bool - // off is the file offset. off is accessed using atomic memory operations. // offMu serializes operations that may mutate off. off int64 @@ -113,16 +109,11 @@ type regularFileFD struct { // Release implements vfs.FileDescriptionImpl.Release. func (fd *regularFileFD) Release() { - if fd.writable { - fd.vfsfd.VirtualDentry().Mount().EndWrite() - } + // noop } // PRead implements vfs.FileDescriptionImpl.PRead. func (fd *regularFileFD) PRead(ctx context.Context, dst usermem.IOSequence, offset int64, opts vfs.ReadOptions) (int64, error) { - if !fd.readable { - return 0, syserror.EINVAL - } if offset < 0 { return 0, syserror.EINVAL } @@ -147,9 +138,6 @@ func (fd *regularFileFD) Read(ctx context.Context, dst usermem.IOSequence, opts // PWrite implements vfs.FileDescriptionImpl.PWrite. func (fd *regularFileFD) PWrite(ctx context.Context, src usermem.IOSequence, offset int64, opts vfs.WriteOptions) (int64, error) { - if !fd.writable { - return 0, syserror.EINVAL - } if offset < 0 { return 0, syserror.EINVAL } diff --git a/pkg/sentry/kernel/pipe/vfs.go b/pkg/sentry/kernel/pipe/vfs.go index bf7461cbb..6f83e3cee 100644 --- a/pkg/sentry/kernel/pipe/vfs.go +++ b/pkg/sentry/kernel/pipe/vfs.go @@ -66,7 +66,7 @@ func NewVFSPipe(sizeBytes, atomicIOBytes int64) *VFSPipe { // for read and write will succeed both in blocking and nonblocking mode. POSIX // leaves this behavior undefined. This can be used to open a FIFO for writing // while there are no readers available." - fifo(7) -func (vp *VFSPipe) NewVFSPipeFD(ctx context.Context, rp *vfs.ResolvingPath, vfsd *vfs.Dentry, vfsfd *vfs.FileDescription, flags uint32) (*VFSPipeFD, error) { +func (vp *VFSPipe) NewVFSPipeFD(ctx context.Context, vfsd *vfs.Dentry, vfsfd *vfs.FileDescription, flags uint32) (*VFSPipeFD, error) { vp.mu.Lock() defer vp.mu.Unlock() @@ -76,7 +76,7 @@ func (vp *VFSPipe) NewVFSPipeFD(ctx context.Context, rp *vfs.ResolvingPath, vfsd return nil, syserror.EINVAL } - vfd, err := vp.open(rp, vfsd, vfsfd, flags) + vfd, err := vp.open(vfsd, vfsfd, flags) if err != nil { return nil, err } @@ -118,19 +118,13 @@ func (vp *VFSPipe) NewVFSPipeFD(ctx context.Context, rp *vfs.ResolvingPath, vfsd } // Preconditions: vp.mu must be held. -func (vp *VFSPipe) open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, vfsfd *vfs.FileDescription, flags uint32) (*VFSPipeFD, error) { +func (vp *VFSPipe) open(vfsd *vfs.Dentry, vfsfd *vfs.FileDescription, flags uint32) (*VFSPipeFD, error) { var fd VFSPipeFD fd.flags = flags fd.readable = vfs.MayReadFileWithOpenFlags(flags) fd.writable = vfs.MayWriteFileWithOpenFlags(flags) fd.vfsfd = vfsfd fd.pipe = &vp.pipe - if fd.writable { - // The corresponding Mount.EndWrite() is in VFSPipe.Release(). - if err := rp.Mount().CheckBeginWrite(); err != nil { - return nil, err - } - } switch { case fd.readable && fd.writable: diff --git a/pkg/sentry/vfs/file_description.go b/pkg/sentry/vfs/file_description.go index 6afe280bc..51c95c2d9 100644 --- a/pkg/sentry/vfs/file_description.go +++ b/pkg/sentry/vfs/file_description.go @@ -49,8 +49,23 @@ type FileDescription struct { // A reference is held on vd. vd is immutable. vd VirtualDentry + // opts contains options passed to FileDescription.Init(). opts is + // immutable. opts FileDescriptionOptions + // readable is MayReadFileWithOpenFlags(statusFlags). readable is + // immutable. + // + // readable is analogous to Linux's FMODE_READ. + readable bool + + // writable is MayWriteFileWithOpenFlags(statusFlags). If writable is true, + // the FileDescription holds a write count on vd.mount. writable is + // immutable. + // + // writable is analogous to Linux's FMODE_WRITE. + writable bool + // impl is the FileDescriptionImpl associated with this Filesystem. impl is // immutable. This should be the last field in FileDescription. impl FileDescriptionImpl @@ -77,10 +92,17 @@ type FileDescriptionOptions struct { UseDentryMetadata bool } -// Init must be called before first use of fd. It takes references on mnt and -// d. statusFlags is the initial file description status flags, which is -// usually the full set of flags passed to open(2). -func (fd *FileDescription) Init(impl FileDescriptionImpl, statusFlags uint32, mnt *Mount, d *Dentry, opts *FileDescriptionOptions) { +// Init must be called before first use of fd. If it succeeds, it takes +// references on mnt and d. statusFlags is the initial file description status +// flags, which is usually the full set of flags passed to open(2). +func (fd *FileDescription) Init(impl FileDescriptionImpl, statusFlags uint32, mnt *Mount, d *Dentry, opts *FileDescriptionOptions) error { + writable := MayWriteFileWithOpenFlags(statusFlags) + if writable { + if err := mnt.CheckBeginWrite(); err != nil { + return err + } + } + fd.refs = 1 fd.statusFlags = statusFlags | linux.O_LARGEFILE fd.vd = VirtualDentry{ @@ -89,7 +111,10 @@ func (fd *FileDescription) Init(impl FileDescriptionImpl, statusFlags uint32, mn } fd.vd.IncRef() fd.opts = *opts + fd.readable = MayReadFileWithOpenFlags(statusFlags) + fd.writable = writable fd.impl = impl + return nil } // IncRef increments fd's reference count. @@ -117,6 +142,9 @@ func (fd *FileDescription) TryIncRef() bool { func (fd *FileDescription) DecRef() { if refs := atomic.AddInt64(&fd.refs, -1); refs == 0 { fd.impl.Release() + if fd.writable { + fd.vd.mount.EndWrite() + } fd.vd.DecRef() } else if refs < 0 { panic("FileDescription.DecRef() called without holding a reference") @@ -194,6 +222,16 @@ func (fd *FileDescription) SetStatusFlags(ctx context.Context, creds *auth.Crede return nil } +// IsReadable returns true if fd was opened for reading. +func (fd *FileDescription) IsReadable() bool { + return fd.readable +} + +// IsWritable returns true if fd was opened for writing. +func (fd *FileDescription) IsWritable() bool { + return fd.writable +} + // Impl returns the FileDescriptionImpl associated with fd. func (fd *FileDescription) Impl() FileDescriptionImpl { return fd.impl @@ -241,6 +279,8 @@ type FileDescriptionImpl interface { // Errors: // // - If opts.Flags specifies unsupported options, PRead returns EOPNOTSUPP. + // + // Preconditions: The FileDescription was opened for reading. PRead(ctx context.Context, dst usermem.IOSequence, offset int64, opts ReadOptions) (int64, error) // Read is similar to PRead, but does not specify an offset. @@ -254,6 +294,8 @@ type FileDescriptionImpl interface { // Errors: // // - If opts.Flags specifies unsupported options, Read returns EOPNOTSUPP. + // + // Preconditions: The FileDescription was opened for reading. Read(ctx context.Context, dst usermem.IOSequence, opts ReadOptions) (int64, error) // PWrite writes src to the file, starting at the given offset, and returns @@ -268,6 +310,8 @@ type FileDescriptionImpl interface { // // - If opts.Flags specifies unsupported options, PWrite returns // EOPNOTSUPP. + // + // Preconditions: The FileDescription was opened for writing. PWrite(ctx context.Context, src usermem.IOSequence, offset int64, opts WriteOptions) (int64, error) // Write is similar to PWrite, but does not specify an offset, which is @@ -281,6 +325,8 @@ type FileDescriptionImpl interface { // Errors: // // - If opts.Flags specifies unsupported options, Write returns EOPNOTSUPP. + // + // Preconditions: The FileDescription was opened for writing. Write(ctx context.Context, src usermem.IOSequence, opts WriteOptions) (int64, error) // IterDirents invokes cb on each entry in the directory represented by the @@ -411,11 +457,17 @@ func (fd *FileDescription) StatFS(ctx context.Context) (linux.Statfs, error) { // offset, and returns the number of bytes read. PRead is permitted to return // partial reads with a nil error. func (fd *FileDescription) PRead(ctx context.Context, dst usermem.IOSequence, offset int64, opts ReadOptions) (int64, error) { + if !fd.readable { + return 0, syserror.EBADF + } return fd.impl.PRead(ctx, dst, offset, opts) } // Read is similar to PRead, but does not specify an offset. func (fd *FileDescription) Read(ctx context.Context, dst usermem.IOSequence, opts ReadOptions) (int64, error) { + if !fd.readable { + return 0, syserror.EBADF + } return fd.impl.Read(ctx, dst, opts) } @@ -423,11 +475,17 @@ func (fd *FileDescription) Read(ctx context.Context, dst usermem.IOSequence, opt // offset, and returns the number of bytes written. PWrite is permitted to // return partial writes with a nil error. func (fd *FileDescription) PWrite(ctx context.Context, src usermem.IOSequence, offset int64, opts WriteOptions) (int64, error) { + if !fd.writable { + return 0, syserror.EBADF + } return fd.impl.PWrite(ctx, src, offset, opts) } // Write is similar to PWrite, but does not specify an offset. func (fd *FileDescription) Write(ctx context.Context, src usermem.IOSequence, opts WriteOptions) (int64, error) { + if !fd.writable { + return 0, syserror.EBADF + } return fd.impl.Write(ctx, src, opts) } diff --git a/pkg/sentry/vfs/permissions.go b/pkg/sentry/vfs/permissions.go index d279d05ca..f664581f4 100644 --- a/pkg/sentry/vfs/permissions.go +++ b/pkg/sentry/vfs/permissions.go @@ -94,14 +94,13 @@ func GenericCheckPermissions(creds *auth.Credentials, ats AccessTypes, isDir boo // the set of accesses permitted for the opened file: // // - O_TRUNC causes MayWrite to be set in the returned AccessTypes (since it -// mutates the file), but does not permit the opened to write to the file +// mutates the file), but does not permit writing to the open file description // thereafter. // // - "Linux reserves the special, nonstandard access mode 3 (binary 11) in // flags to mean: check for read and write permission on the file and return a // file descriptor that can't be used for reading or writing." - open(2). Thus -// AccessTypesForOpenFlags returns MayRead|MayWrite in this case, but -// filesystems are responsible for ensuring that access is denied. +// AccessTypesForOpenFlags returns MayRead|MayWrite in this case. // // Use May{Read,Write}FileWithOpenFlags() for these checks instead. func AccessTypesForOpenFlags(flags uint32) AccessTypes { -- cgit v1.2.3 From 18a7e1309decb9bc09879e337adbc00f81d420c5 Mon Sep 17 00:00:00 2001 From: Jamie Liu Date: Fri, 24 Jan 2020 17:06:30 -0800 Subject: Add support for device special files to VFS2 tmpfs. PiperOrigin-RevId: 291471892 --- pkg/sentry/fsimpl/tmpfs/BUILD | 1 + pkg/sentry/fsimpl/tmpfs/device_file.go | 39 ++++++++++++++++++++++++++++++ pkg/sentry/fsimpl/tmpfs/filesystem.go | 43 +++++++++++++++++++--------------- pkg/sentry/fsimpl/tmpfs/tmpfs.go | 30 +++++++++++++++++++----- 4 files changed, 88 insertions(+), 25 deletions(-) create mode 100644 pkg/sentry/fsimpl/tmpfs/device_file.go (limited to 'pkg/sentry/fsimpl/tmpfs/filesystem.go') diff --git a/pkg/sentry/fsimpl/tmpfs/BUILD b/pkg/sentry/fsimpl/tmpfs/BUILD index 7601c7c04..691476b4f 100644 --- a/pkg/sentry/fsimpl/tmpfs/BUILD +++ b/pkg/sentry/fsimpl/tmpfs/BUILD @@ -20,6 +20,7 @@ go_library( name = "tmpfs", srcs = [ "dentry_list.go", + "device_file.go", "directory.go", "filesystem.go", "named_pipe.go", diff --git a/pkg/sentry/fsimpl/tmpfs/device_file.go b/pkg/sentry/fsimpl/tmpfs/device_file.go new file mode 100644 index 000000000..84b181b90 --- /dev/null +++ b/pkg/sentry/fsimpl/tmpfs/device_file.go @@ -0,0 +1,39 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package tmpfs + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/kernel/auth" + "gvisor.dev/gvisor/pkg/sentry/vfs" +) + +type deviceFile struct { + inode inode + kind vfs.DeviceKind + major uint32 + minor uint32 +} + +func (fs *filesystem) newDeviceFile(creds *auth.Credentials, mode linux.FileMode, kind vfs.DeviceKind, major, minor uint32) *inode { + file := &deviceFile{ + kind: kind, + major: major, + minor: minor, + } + file.inode.init(file, fs, creds, mode) + file.inode.nlink = 1 // from parent directory + return &file.inode +} diff --git a/pkg/sentry/fsimpl/tmpfs/filesystem.go b/pkg/sentry/fsimpl/tmpfs/filesystem.go index a9f66a42a..d726f03c5 100644 --- a/pkg/sentry/fsimpl/tmpfs/filesystem.go +++ b/pkg/sentry/fsimpl/tmpfs/filesystem.go @@ -228,23 +228,26 @@ func (fs *filesystem) MkdirAt(ctx context.Context, rp *vfs.ResolvingPath, opts v // MknodAt implements vfs.FilesystemImpl.MknodAt. func (fs *filesystem) MknodAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.MknodOptions) error { return fs.doCreateAt(rp, false /* dir */, func(parent *dentry, name string) error { + var childInode *inode switch opts.Mode.FileType() { case 0, linux.S_IFREG: - child := fs.newDentry(fs.newRegularFile(rp.Credentials(), opts.Mode)) - parent.vfsd.InsertChild(&child.vfsd, name) - parent.inode.impl.(*directory).childList.PushBack(child) - return nil + childInode = fs.newRegularFile(rp.Credentials(), opts.Mode) case linux.S_IFIFO: - child := fs.newDentry(fs.newNamedPipe(rp.Credentials(), opts.Mode)) - parent.vfsd.InsertChild(&child.vfsd, name) - parent.inode.impl.(*directory).childList.PushBack(child) - return nil - case linux.S_IFBLK, linux.S_IFCHR, linux.S_IFSOCK: + childInode = fs.newNamedPipe(rp.Credentials(), opts.Mode) + case linux.S_IFBLK: + childInode = fs.newDeviceFile(rp.Credentials(), opts.Mode, vfs.BlockDevice, opts.DevMajor, opts.DevMinor) + case linux.S_IFCHR: + childInode = fs.newDeviceFile(rp.Credentials(), opts.Mode, vfs.CharDevice, opts.DevMajor, opts.DevMinor) + case linux.S_IFSOCK: // Not yet supported. return syserror.EPERM default: return syserror.EINVAL } + child := fs.newDentry(childInode) + parent.vfsd.InsertChild(&child.vfsd, name) + parent.inode.impl.(*directory).childList.PushBack(child) + return nil }) } @@ -264,7 +267,7 @@ func (fs *filesystem) OpenAt(ctx context.Context, rp *vfs.ResolvingPath, opts vf if err != nil { return nil, err } - return d.open(ctx, rp, opts.Flags, false /* afterCreate */) + return d.open(ctx, rp, &opts, false /* afterCreate */) } mustCreate := opts.Flags&linux.O_EXCL != 0 @@ -279,7 +282,7 @@ func (fs *filesystem) OpenAt(ctx context.Context, rp *vfs.ResolvingPath, opts vf if mustCreate { return nil, syserror.EEXIST } - return start.open(ctx, rp, opts.Flags, false /* afterCreate */) + return start.open(ctx, rp, &opts, false /* afterCreate */) } afterTrailingSymlink: parent, err := walkParentDirLocked(rp, start) @@ -313,7 +316,7 @@ afterTrailingSymlink: child := fs.newDentry(fs.newRegularFile(rp.Credentials(), opts.Mode)) parent.vfsd.InsertChild(&child.vfsd, name) parent.inode.impl.(*directory).childList.PushBack(child) - return child.open(ctx, rp, opts.Flags, true) + return child.open(ctx, rp, &opts, true) } if err != nil { return nil, err @@ -327,11 +330,11 @@ afterTrailingSymlink: if mustCreate { return nil, syserror.EEXIST } - return child.open(ctx, rp, opts.Flags, false) + return child.open(ctx, rp, &opts, false) } -func (d *dentry) open(ctx context.Context, rp *vfs.ResolvingPath, flags uint32, afterCreate bool) (*vfs.FileDescription, error) { - ats := vfs.AccessTypesForOpenFlags(flags) +func (d *dentry) open(ctx context.Context, rp *vfs.ResolvingPath, opts *vfs.OpenOptions, afterCreate bool) (*vfs.FileDescription, error) { + ats := vfs.AccessTypesForOpenFlags(opts.Flags) if !afterCreate { if err := d.inode.checkPermissions(rp.Credentials(), ats, d.inode.isDir()); err != nil { return nil, err @@ -340,10 +343,10 @@ func (d *dentry) open(ctx context.Context, rp *vfs.ResolvingPath, flags uint32, switch impl := d.inode.impl.(type) { case *regularFile: var fd regularFileFD - if err := fd.vfsfd.Init(&fd, flags, rp.Mount(), &d.vfsd, &vfs.FileDescriptionOptions{}); err != nil { + if err := fd.vfsfd.Init(&fd, opts.Flags, rp.Mount(), &d.vfsd, &vfs.FileDescriptionOptions{}); err != nil { return nil, err } - if flags&linux.O_TRUNC != 0 { + if opts.Flags&linux.O_TRUNC != 0 { impl.mu.Lock() impl.data.Truncate(0, impl.memFile) atomic.StoreUint64(&impl.size, 0) @@ -356,7 +359,7 @@ func (d *dentry) open(ctx context.Context, rp *vfs.ResolvingPath, flags uint32, return nil, syserror.EISDIR } var fd directoryFD - if err := fd.vfsfd.Init(&fd, flags, rp.Mount(), &d.vfsd, &vfs.FileDescriptionOptions{}); err != nil { + if err := fd.vfsfd.Init(&fd, opts.Flags, rp.Mount(), &d.vfsd, &vfs.FileDescriptionOptions{}); err != nil { return nil, err } return &fd.vfsfd, nil @@ -364,7 +367,9 @@ func (d *dentry) open(ctx context.Context, rp *vfs.ResolvingPath, flags uint32, // Can't open symlinks without O_PATH (which is unimplemented). return nil, syserror.ELOOP case *namedPipe: - return newNamedPipeFD(ctx, impl, rp, &d.vfsd, flags) + return newNamedPipeFD(ctx, impl, rp, &d.vfsd, opts.Flags) + case *deviceFile: + return rp.VirtualFilesystem().OpenDeviceSpecialFile(ctx, rp.Mount(), &d.vfsd, impl.kind, impl.major, impl.minor, opts) default: panic(fmt.Sprintf("unknown inode type: %T", d.inode.impl)) } diff --git a/pkg/sentry/fsimpl/tmpfs/tmpfs.go b/pkg/sentry/fsimpl/tmpfs/tmpfs.go index 1d4889c89..515f033f2 100644 --- a/pkg/sentry/fsimpl/tmpfs/tmpfs.go +++ b/pkg/sentry/fsimpl/tmpfs/tmpfs.go @@ -149,6 +149,10 @@ type inode struct { ctime int64 // nanoseconds mtime int64 // nanoseconds + // Only meaningful for device special files. + rdevMajor uint32 + rdevMinor uint32 + impl interface{} // immutable } @@ -269,6 +273,15 @@ func (i *inode) statTo(stat *linux.Statx) { stat.Blocks = allocatedBlocksForSize(stat.Size) case *namedPipe: stat.Mode |= linux.S_IFIFO + case *deviceFile: + switch impl.kind { + case vfs.BlockDevice: + stat.Mode |= linux.S_IFBLK + case vfs.CharDevice: + stat.Mode |= linux.S_IFCHR + } + stat.RdevMajor = impl.major + stat.RdevMinor = impl.minor default: panic(fmt.Sprintf("unknown inode type: %T", i.impl)) } @@ -309,12 +322,8 @@ func (i *inode) setStat(stat linux.Statx) error { } case *directory: return syserror.EISDIR - case *symlink: - return syserror.EINVAL - case *namedPipe: - // Nothing. default: - panic(fmt.Sprintf("unknown inode type: %T", i.impl)) + return syserror.EINVAL } } if mask&linux.STATX_ATIME != 0 { @@ -353,13 +362,22 @@ func allocatedBlocksForSize(size uint64) uint64 { } func (i *inode) direntType() uint8 { - switch i.impl.(type) { + switch impl := i.impl.(type) { case *regularFile: return linux.DT_REG case *directory: return linux.DT_DIR case *symlink: return linux.DT_LNK + case *deviceFile: + switch impl.kind { + case vfs.BlockDevice: + return linux.DT_BLK + case vfs.CharDevice: + return linux.DT_CHR + default: + panic(fmt.Sprintf("unknown vfs.DeviceKind: %v", impl.kind)) + } default: panic(fmt.Sprintf("unknown inode type: %T", i.impl)) } -- cgit v1.2.3 From 0e2f1b7abd219f39d67cc2cecd00c441a13eeb29 Mon Sep 17 00:00:00 2001 From: Adin Scannell Date: Mon, 27 Jan 2020 15:17:58 -0800 Subject: Update package locations. Because the abi will depend on the core types for marshalling (usermem, context, safemem, safecopy), these need to be flattened from the sentry directory. These packages contain no sentry-specific details. PiperOrigin-RevId: 291811289 --- pkg/abi/abi.go | 4 + pkg/context/BUILD | 13 + pkg/context/context.go | 141 +++++ pkg/safecopy/BUILD | 29 + pkg/safecopy/LICENSE | 27 + pkg/safecopy/atomic_amd64.s | 136 +++++ pkg/safecopy/atomic_arm64.s | 126 +++++ pkg/safecopy/memclr_amd64.s | 147 +++++ pkg/safecopy/memclr_arm64.s | 74 +++ pkg/safecopy/memcpy_amd64.s | 250 +++++++++ pkg/safecopy/memcpy_arm64.s | 78 +++ pkg/safecopy/safecopy.go | 144 +++++ pkg/safecopy/safecopy_test.go | 617 +++++++++++++++++++++ pkg/safecopy/safecopy_unsafe.go | 335 +++++++++++ pkg/safecopy/sighandler_amd64.s | 133 +++++ pkg/safecopy/sighandler_arm64.s | 143 +++++ pkg/safemem/BUILD | 27 + pkg/safemem/block_unsafe.go | 279 ++++++++++ pkg/safemem/io.go | 392 +++++++++++++ pkg/safemem/io_test.go | 199 +++++++ pkg/safemem/safemem.go | 16 + pkg/safemem/seq_test.go | 196 +++++++ pkg/safemem/seq_unsafe.go | 299 ++++++++++ pkg/sentry/arch/BUILD | 4 +- pkg/sentry/arch/arch.go | 2 +- pkg/sentry/arch/arch_aarch64.go | 2 +- pkg/sentry/arch/arch_amd64.go | 2 +- pkg/sentry/arch/arch_arm64.go | 2 +- pkg/sentry/arch/arch_state_x86.go | 2 +- pkg/sentry/arch/arch_x86.go | 2 +- pkg/sentry/arch/auxv.go | 2 +- pkg/sentry/arch/signal.go | 2 +- pkg/sentry/arch/signal_amd64.go | 2 +- pkg/sentry/arch/signal_arm64.go | 2 +- pkg/sentry/arch/signal_stack.go | 2 +- pkg/sentry/arch/stack.go | 4 +- pkg/sentry/context/BUILD | 13 - pkg/sentry/context/context.go | 141 ----- pkg/sentry/context/contexttest/BUILD | 21 - pkg/sentry/context/contexttest/contexttest.go | 188 ------- pkg/sentry/contexttest/BUILD | 21 + pkg/sentry/contexttest/contexttest.go | 188 +++++++ pkg/sentry/fs/BUILD | 12 +- pkg/sentry/fs/anon/BUILD | 4 +- pkg/sentry/fs/anon/anon.go | 4 +- pkg/sentry/fs/attr.go | 2 +- pkg/sentry/fs/context.go | 2 +- pkg/sentry/fs/copy_up.go | 4 +- pkg/sentry/fs/copy_up_test.go | 2 +- pkg/sentry/fs/dev/BUILD | 6 +- pkg/sentry/fs/dev/dev.go | 4 +- pkg/sentry/fs/dev/fs.go | 2 +- pkg/sentry/fs/dev/full.go | 4 +- pkg/sentry/fs/dev/null.go | 2 +- pkg/sentry/fs/dev/random.go | 6 +- pkg/sentry/fs/dev/tty.go | 2 +- pkg/sentry/fs/dirent.go | 2 +- pkg/sentry/fs/dirent_refs_test.go | 4 +- pkg/sentry/fs/fdpipe/BUILD | 12 +- pkg/sentry/fs/fdpipe/pipe.go | 6 +- pkg/sentry/fs/fdpipe/pipe_opener.go | 2 +- pkg/sentry/fs/fdpipe/pipe_opener_test.go | 6 +- pkg/sentry/fs/fdpipe/pipe_state.go | 2 +- pkg/sentry/fs/fdpipe/pipe_test.go | 4 +- pkg/sentry/fs/file.go | 4 +- pkg/sentry/fs/file_operations.go | 4 +- pkg/sentry/fs/file_overlay.go | 4 +- pkg/sentry/fs/file_overlay_test.go | 2 +- pkg/sentry/fs/filesystems.go | 2 +- pkg/sentry/fs/filetest/BUILD | 6 +- pkg/sentry/fs/filetest/filetest.go | 6 +- pkg/sentry/fs/fs.go | 2 +- pkg/sentry/fs/fsutil/BUILD | 14 +- pkg/sentry/fs/fsutil/dirty_set.go | 6 +- pkg/sentry/fs/fsutil/dirty_set_test.go | 2 +- pkg/sentry/fs/fsutil/file.go | 4 +- pkg/sentry/fs/fsutil/file_range_set.go | 6 +- pkg/sentry/fs/fsutil/host_file_mapper.go | 4 +- pkg/sentry/fs/fsutil/host_file_mapper_unsafe.go | 2 +- pkg/sentry/fs/fsutil/host_mappable.go | 6 +- pkg/sentry/fs/fsutil/inode.go | 2 +- pkg/sentry/fs/fsutil/inode_cached.go | 6 +- pkg/sentry/fs/fsutil/inode_cached_test.go | 8 +- pkg/sentry/fs/gofer/BUILD | 10 +- pkg/sentry/fs/gofer/attr.go | 4 +- pkg/sentry/fs/gofer/cache_policy.go | 2 +- pkg/sentry/fs/gofer/context_file.go | 2 +- pkg/sentry/fs/gofer/file.go | 4 +- pkg/sentry/fs/gofer/file_state.go | 2 +- pkg/sentry/fs/gofer/fs.go | 2 +- pkg/sentry/fs/gofer/gofer_test.go | 4 +- pkg/sentry/fs/gofer/handles.go | 4 +- pkg/sentry/fs/gofer/inode.go | 4 +- pkg/sentry/fs/gofer/inode_state.go | 2 +- pkg/sentry/fs/gofer/path.go | 2 +- pkg/sentry/fs/gofer/session.go | 2 +- pkg/sentry/fs/gofer/session_state.go | 2 +- pkg/sentry/fs/gofer/socket.go | 2 +- pkg/sentry/fs/gofer/util.go | 2 +- pkg/sentry/fs/host/BUILD | 12 +- pkg/sentry/fs/host/control.go | 2 +- pkg/sentry/fs/host/file.go | 6 +- pkg/sentry/fs/host/fs.go | 2 +- pkg/sentry/fs/host/fs_test.go | 4 +- pkg/sentry/fs/host/inode.go | 4 +- pkg/sentry/fs/host/inode_state.go | 2 +- pkg/sentry/fs/host/inode_test.go | 2 +- pkg/sentry/fs/host/socket.go | 2 +- pkg/sentry/fs/host/socket_test.go | 4 +- pkg/sentry/fs/host/tty.go | 4 +- pkg/sentry/fs/host/wait_test.go | 2 +- pkg/sentry/fs/inode.go | 2 +- pkg/sentry/fs/inode_operations.go | 2 +- pkg/sentry/fs/inode_overlay.go | 2 +- pkg/sentry/fs/inode_overlay_test.go | 2 +- pkg/sentry/fs/inotify.go | 4 +- pkg/sentry/fs/inotify_event.go | 4 +- pkg/sentry/fs/mock.go | 2 +- pkg/sentry/fs/mount.go | 2 +- pkg/sentry/fs/mount_overlay.go | 2 +- pkg/sentry/fs/mount_test.go | 2 +- pkg/sentry/fs/mounts.go | 2 +- pkg/sentry/fs/mounts_test.go | 2 +- pkg/sentry/fs/offset.go | 2 +- pkg/sentry/fs/overlay.go | 4 +- pkg/sentry/fs/proc/BUILD | 8 +- pkg/sentry/fs/proc/cgroup.go | 2 +- pkg/sentry/fs/proc/cpuinfo.go | 2 +- pkg/sentry/fs/proc/exec_args.go | 4 +- pkg/sentry/fs/proc/fds.go | 2 +- pkg/sentry/fs/proc/filesystems.go | 2 +- pkg/sentry/fs/proc/fs.go | 2 +- pkg/sentry/fs/proc/inode.go | 4 +- pkg/sentry/fs/proc/loadavg.go | 2 +- pkg/sentry/fs/proc/meminfo.go | 4 +- pkg/sentry/fs/proc/mounts.go | 2 +- pkg/sentry/fs/proc/net.go | 4 +- pkg/sentry/fs/proc/proc.go | 2 +- pkg/sentry/fs/proc/seqfile/BUILD | 10 +- pkg/sentry/fs/proc/seqfile/seqfile.go | 4 +- pkg/sentry/fs/proc/seqfile/seqfile_test.go | 6 +- pkg/sentry/fs/proc/stat.go | 2 +- pkg/sentry/fs/proc/sys.go | 4 +- pkg/sentry/fs/proc/sys_net.go | 4 +- pkg/sentry/fs/proc/sys_net_test.go | 4 +- pkg/sentry/fs/proc/task.go | 4 +- pkg/sentry/fs/proc/uid_gid_map.go | 4 +- pkg/sentry/fs/proc/uptime.go | 4 +- pkg/sentry/fs/proc/version.go | 2 +- pkg/sentry/fs/ramfs/BUILD | 6 +- pkg/sentry/fs/ramfs/dir.go | 2 +- pkg/sentry/fs/ramfs/socket.go | 2 +- pkg/sentry/fs/ramfs/symlink.go | 2 +- pkg/sentry/fs/ramfs/tree.go | 4 +- pkg/sentry/fs/ramfs/tree_test.go | 2 +- pkg/sentry/fs/splice.go | 2 +- pkg/sentry/fs/sys/BUILD | 4 +- pkg/sentry/fs/sys/devices.go | 2 +- pkg/sentry/fs/sys/fs.go | 2 +- pkg/sentry/fs/sys/sys.go | 4 +- pkg/sentry/fs/timerfd/BUILD | 4 +- pkg/sentry/fs/timerfd/timerfd.go | 4 +- pkg/sentry/fs/tmpfs/BUILD | 10 +- pkg/sentry/fs/tmpfs/file_regular.go | 4 +- pkg/sentry/fs/tmpfs/file_test.go | 4 +- pkg/sentry/fs/tmpfs/fs.go | 2 +- pkg/sentry/fs/tmpfs/inode_file.go | 6 +- pkg/sentry/fs/tmpfs/tmpfs.go | 4 +- pkg/sentry/fs/tty/BUILD | 10 +- pkg/sentry/fs/tty/dir.go | 4 +- pkg/sentry/fs/tty/fs.go | 2 +- pkg/sentry/fs/tty/line_discipline.go | 4 +- pkg/sentry/fs/tty/master.go | 4 +- pkg/sentry/fs/tty/queue.go | 6 +- pkg/sentry/fs/tty/slave.go | 4 +- pkg/sentry/fs/tty/terminal.go | 4 +- pkg/sentry/fs/tty/tty_test.go | 4 +- pkg/sentry/fsimpl/ext/BUILD | 12 +- pkg/sentry/fsimpl/ext/benchmark/BUILD | 4 +- pkg/sentry/fsimpl/ext/benchmark/benchmark_test.go | 4 +- pkg/sentry/fsimpl/ext/directory.go | 2 +- pkg/sentry/fsimpl/ext/ext.go | 2 +- pkg/sentry/fsimpl/ext/ext_test.go | 6 +- pkg/sentry/fsimpl/ext/file_description.go | 2 +- pkg/sentry/fsimpl/ext/filesystem.go | 2 +- pkg/sentry/fsimpl/ext/regular_file.go | 6 +- pkg/sentry/fsimpl/ext/symlink.go | 4 +- pkg/sentry/fsimpl/kernfs/BUILD | 10 +- pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go | 4 +- pkg/sentry/fsimpl/kernfs/fd_impl_util.go | 4 +- pkg/sentry/fsimpl/kernfs/filesystem.go | 2 +- pkg/sentry/fsimpl/kernfs/inode_impl_util.go | 2 +- pkg/sentry/fsimpl/kernfs/kernfs.go | 2 +- pkg/sentry/fsimpl/kernfs/kernfs_test.go | 6 +- pkg/sentry/fsimpl/kernfs/symlink.go | 2 +- pkg/sentry/fsimpl/proc/BUILD | 12 +- pkg/sentry/fsimpl/proc/filesystem.go | 2 +- pkg/sentry/fsimpl/proc/subtasks.go | 2 +- pkg/sentry/fsimpl/proc/task.go | 2 +- pkg/sentry/fsimpl/proc/task_files.go | 6 +- pkg/sentry/fsimpl/proc/tasks.go | 2 +- pkg/sentry/fsimpl/proc/tasks_files.go | 4 +- pkg/sentry/fsimpl/proc/tasks_net.go | 4 +- pkg/sentry/fsimpl/proc/tasks_sys.go | 2 +- pkg/sentry/fsimpl/proc/tasks_sys_test.go | 2 +- pkg/sentry/fsimpl/proc/tasks_test.go | 4 +- pkg/sentry/fsimpl/sys/BUILD | 2 +- pkg/sentry/fsimpl/sys/sys.go | 2 +- pkg/sentry/fsimpl/testutil/BUILD | 4 +- pkg/sentry/fsimpl/testutil/kernel.go | 2 +- pkg/sentry/fsimpl/testutil/testutil.go | 4 +- pkg/sentry/fsimpl/tmpfs/BUILD | 16 +- pkg/sentry/fsimpl/tmpfs/benchmark_test.go | 4 +- pkg/sentry/fsimpl/tmpfs/directory.go | 2 +- pkg/sentry/fsimpl/tmpfs/filesystem.go | 2 +- pkg/sentry/fsimpl/tmpfs/named_pipe.go | 4 +- pkg/sentry/fsimpl/tmpfs/pipe_test.go | 6 +- pkg/sentry/fsimpl/tmpfs/regular_file.go | 6 +- pkg/sentry/fsimpl/tmpfs/regular_file_test.go | 4 +- pkg/sentry/fsimpl/tmpfs/tmpfs.go | 2 +- pkg/sentry/hostmm/BUILD | 2 +- pkg/sentry/hostmm/hostmm.go | 2 +- pkg/sentry/inet/BUILD | 2 +- pkg/sentry/inet/context.go | 2 +- pkg/sentry/kernel/BUILD | 12 +- pkg/sentry/kernel/auth/BUILD | 2 +- pkg/sentry/kernel/auth/context.go | 2 +- pkg/sentry/kernel/auth/id_map.go | 2 +- pkg/sentry/kernel/context.go | 2 +- pkg/sentry/kernel/contexttest/BUILD | 4 +- pkg/sentry/kernel/contexttest/contexttest.go | 4 +- pkg/sentry/kernel/epoll/BUILD | 6 +- pkg/sentry/kernel/epoll/epoll.go | 4 +- pkg/sentry/kernel/epoll/epoll_test.go | 2 +- pkg/sentry/kernel/eventfd/BUILD | 8 +- pkg/sentry/kernel/eventfd/eventfd.go | 4 +- pkg/sentry/kernel/eventfd/eventfd_test.go | 4 +- pkg/sentry/kernel/fd_table.go | 2 +- pkg/sentry/kernel/fd_table_test.go | 4 +- pkg/sentry/kernel/futex/BUILD | 6 +- pkg/sentry/kernel/futex/futex.go | 2 +- pkg/sentry/kernel/futex/futex_test.go | 2 +- pkg/sentry/kernel/kernel.go | 2 +- pkg/sentry/kernel/pipe/BUILD | 12 +- pkg/sentry/kernel/pipe/buffer.go | 2 +- pkg/sentry/kernel/pipe/buffer_test.go | 2 +- pkg/sentry/kernel/pipe/node.go | 2 +- pkg/sentry/kernel/pipe/node_test.go | 6 +- pkg/sentry/kernel/pipe/pipe.go | 2 +- pkg/sentry/kernel/pipe/pipe_test.go | 4 +- pkg/sentry/kernel/pipe/pipe_util.go | 4 +- pkg/sentry/kernel/pipe/reader_writer.go | 4 +- pkg/sentry/kernel/pipe/vfs.go | 4 +- pkg/sentry/kernel/ptrace.go | 2 +- pkg/sentry/kernel/ptrace_amd64.go | 2 +- pkg/sentry/kernel/ptrace_arm64.go | 2 +- pkg/sentry/kernel/rseq.go | 2 +- pkg/sentry/kernel/seccomp.go | 2 +- pkg/sentry/kernel/semaphore/BUILD | 6 +- pkg/sentry/kernel/semaphore/semaphore.go | 2 +- pkg/sentry/kernel/semaphore/semaphore_test.go | 4 +- pkg/sentry/kernel/shm/BUILD | 4 +- pkg/sentry/kernel/shm/shm.go | 4 +- pkg/sentry/kernel/signalfd/BUILD | 4 +- pkg/sentry/kernel/signalfd/signalfd.go | 4 +- pkg/sentry/kernel/syscalls.go | 2 +- pkg/sentry/kernel/task.go | 4 +- pkg/sentry/kernel/task_clone.go | 2 +- pkg/sentry/kernel/task_context.go | 4 +- pkg/sentry/kernel/task_futex.go | 2 +- pkg/sentry/kernel/task_log.go | 2 +- pkg/sentry/kernel/task_run.go | 2 +- pkg/sentry/kernel/task_signals.go | 2 +- pkg/sentry/kernel/task_start.go | 2 +- pkg/sentry/kernel/task_syscall.go | 2 +- pkg/sentry/kernel/task_usermem.go | 2 +- pkg/sentry/kernel/time/BUILD | 2 +- pkg/sentry/kernel/time/context.go | 2 +- pkg/sentry/kernel/timekeeper_test.go | 4 +- pkg/sentry/kernel/vdso.go | 4 +- pkg/sentry/limits/BUILD | 2 +- pkg/sentry/limits/context.go | 2 +- pkg/sentry/loader/BUILD | 6 +- pkg/sentry/loader/elf.go | 4 +- pkg/sentry/loader/interpreter.go | 4 +- pkg/sentry/loader/loader.go | 4 +- pkg/sentry/loader/vdso.go | 6 +- pkg/sentry/memmap/BUILD | 6 +- pkg/sentry/memmap/mapping_set.go | 2 +- pkg/sentry/memmap/mapping_set_test.go | 2 +- pkg/sentry/memmap/memmap.go | 4 +- pkg/sentry/mm/BUILD | 18 +- pkg/sentry/mm/address_space.go | 2 +- pkg/sentry/mm/aio_context.go | 4 +- pkg/sentry/mm/debug.go | 2 +- pkg/sentry/mm/io.go | 6 +- pkg/sentry/mm/lifecycle.go | 4 +- pkg/sentry/mm/metadata.go | 2 +- pkg/sentry/mm/mm.go | 4 +- pkg/sentry/mm/mm_test.go | 6 +- pkg/sentry/mm/pma.go | 8 +- pkg/sentry/mm/procfs.go | 4 +- pkg/sentry/mm/save_restore.go | 2 +- pkg/sentry/mm/shm.go | 4 +- pkg/sentry/mm/special_mappable.go | 4 +- pkg/sentry/mm/syscalls.go | 4 +- pkg/sentry/mm/vma.go | 4 +- pkg/sentry/pgalloc/BUILD | 8 +- pkg/sentry/pgalloc/context.go | 2 +- pkg/sentry/pgalloc/pgalloc.go | 6 +- pkg/sentry/pgalloc/pgalloc_test.go | 2 +- pkg/sentry/pgalloc/save_restore.go | 2 +- pkg/sentry/platform/BUILD | 8 +- pkg/sentry/platform/context.go | 2 +- pkg/sentry/platform/kvm/BUILD | 6 +- pkg/sentry/platform/kvm/address_space.go | 2 +- pkg/sentry/platform/kvm/bluepill.go | 2 +- pkg/sentry/platform/kvm/bluepill_fault.go | 2 +- pkg/sentry/platform/kvm/context.go | 2 +- pkg/sentry/platform/kvm/kvm.go | 2 +- pkg/sentry/platform/kvm/kvm_test.go | 2 +- pkg/sentry/platform/kvm/machine.go | 2 +- pkg/sentry/platform/kvm/machine_amd64.go | 2 +- pkg/sentry/platform/kvm/machine_arm64.go | 2 +- pkg/sentry/platform/kvm/machine_arm64_unsafe.go | 2 +- pkg/sentry/platform/kvm/physical_map.go | 2 +- pkg/sentry/platform/kvm/virtual_map.go | 2 +- pkg/sentry/platform/kvm/virtual_map_test.go | 2 +- pkg/sentry/platform/mmap_min_addr.go | 2 +- pkg/sentry/platform/platform.go | 4 +- pkg/sentry/platform/ptrace/BUILD | 4 +- pkg/sentry/platform/ptrace/ptrace.go | 2 +- pkg/sentry/platform/ptrace/ptrace_unsafe.go | 2 +- pkg/sentry/platform/ptrace/stub_unsafe.go | 4 +- pkg/sentry/platform/ptrace/subprocess.go | 2 +- pkg/sentry/platform/ring0/BUILD | 2 +- pkg/sentry/platform/ring0/defs_amd64.go | 2 +- pkg/sentry/platform/ring0/defs_arm64.go | 2 +- pkg/sentry/platform/ring0/gen_offsets/BUILD | 2 +- pkg/sentry/platform/ring0/pagetables/BUILD | 4 +- .../platform/ring0/pagetables/allocator_unsafe.go | 2 +- pkg/sentry/platform/ring0/pagetables/pagetables.go | 2 +- .../ring0/pagetables/pagetables_aarch64.go | 2 +- .../ring0/pagetables/pagetables_amd64_test.go | 2 +- .../ring0/pagetables/pagetables_arm64_test.go | 2 +- .../platform/ring0/pagetables/pagetables_test.go | 2 +- .../platform/ring0/pagetables/pagetables_x86.go | 2 +- pkg/sentry/platform/safecopy/BUILD | 29 - pkg/sentry/platform/safecopy/LICENSE | 27 - pkg/sentry/platform/safecopy/atomic_amd64.s | 136 ----- pkg/sentry/platform/safecopy/atomic_arm64.s | 126 ----- pkg/sentry/platform/safecopy/memclr_amd64.s | 147 ----- pkg/sentry/platform/safecopy/memclr_arm64.s | 74 --- pkg/sentry/platform/safecopy/memcpy_amd64.s | 250 --------- pkg/sentry/platform/safecopy/memcpy_arm64.s | 78 --- pkg/sentry/platform/safecopy/safecopy.go | 144 ----- pkg/sentry/platform/safecopy/safecopy_test.go | 617 --------------------- pkg/sentry/platform/safecopy/safecopy_unsafe.go | 335 ----------- pkg/sentry/platform/safecopy/sighandler_amd64.s | 133 ----- pkg/sentry/platform/safecopy/sighandler_arm64.s | 143 ----- pkg/sentry/safemem/BUILD | 27 - pkg/sentry/safemem/block_unsafe.go | 279 ---------- pkg/sentry/safemem/io.go | 392 ------------- pkg/sentry/safemem/io_test.go | 199 ------- pkg/sentry/safemem/safemem.go | 16 - pkg/sentry/safemem/seq_test.go | 196 ------- pkg/sentry/safemem/seq_unsafe.go | 299 ---------- pkg/sentry/socket/BUILD | 4 +- pkg/sentry/socket/control/BUILD | 4 +- pkg/sentry/socket/control/control.go | 4 +- pkg/sentry/socket/hostinet/BUILD | 6 +- pkg/sentry/socket/hostinet/socket.go | 6 +- pkg/sentry/socket/hostinet/socket_unsafe.go | 4 +- pkg/sentry/socket/hostinet/stack.go | 4 +- pkg/sentry/socket/netfilter/BUILD | 2 +- pkg/sentry/socket/netfilter/netfilter.go | 2 +- pkg/sentry/socket/netlink/BUILD | 4 +- pkg/sentry/socket/netlink/message.go | 2 +- pkg/sentry/socket/netlink/provider.go | 2 +- pkg/sentry/socket/netlink/route/BUILD | 2 +- pkg/sentry/socket/netlink/route/protocol.go | 2 +- pkg/sentry/socket/netlink/socket.go | 4 +- pkg/sentry/socket/netlink/uevent/BUILD | 2 +- pkg/sentry/socket/netlink/uevent/protocol.go | 2 +- pkg/sentry/socket/netstack/BUILD | 6 +- pkg/sentry/socket/netstack/netstack.go | 6 +- pkg/sentry/socket/netstack/provider.go | 2 +- pkg/sentry/socket/socket.go | 4 +- pkg/sentry/socket/unix/BUILD | 6 +- pkg/sentry/socket/unix/io.go | 4 +- pkg/sentry/socket/unix/transport/BUILD | 2 +- pkg/sentry/socket/unix/transport/connectioned.go | 2 +- pkg/sentry/socket/unix/transport/connectionless.go | 2 +- pkg/sentry/socket/unix/transport/unix.go | 2 +- pkg/sentry/socket/unix/unix.go | 4 +- pkg/sentry/strace/BUILD | 2 +- pkg/sentry/strace/poll.go | 2 +- pkg/sentry/strace/select.go | 2 +- pkg/sentry/strace/signal.go | 2 +- pkg/sentry/strace/socket.go | 2 +- pkg/sentry/strace/strace.go | 2 +- pkg/sentry/syscalls/linux/BUILD | 6 +- pkg/sentry/syscalls/linux/linux64_amd64.go | 2 +- pkg/sentry/syscalls/linux/linux64_arm64.go | 2 +- pkg/sentry/syscalls/linux/sigset.go | 2 +- pkg/sentry/syscalls/linux/sys_aio.go | 2 +- pkg/sentry/syscalls/linux/sys_epoll.go | 2 +- pkg/sentry/syscalls/linux/sys_file.go | 4 +- pkg/sentry/syscalls/linux/sys_futex.go | 2 +- pkg/sentry/syscalls/linux/sys_getdents.go | 2 +- pkg/sentry/syscalls/linux/sys_mempolicy.go | 2 +- pkg/sentry/syscalls/linux/sys_mmap.go | 2 +- pkg/sentry/syscalls/linux/sys_mount.go | 2 +- pkg/sentry/syscalls/linux/sys_pipe.go | 2 +- pkg/sentry/syscalls/linux/sys_poll.go | 2 +- pkg/sentry/syscalls/linux/sys_random.go | 4 +- pkg/sentry/syscalls/linux/sys_read.go | 2 +- pkg/sentry/syscalls/linux/sys_rlimit.go | 2 +- pkg/sentry/syscalls/linux/sys_seccomp.go | 2 +- pkg/sentry/syscalls/linux/sys_sem.go | 2 +- pkg/sentry/syscalls/linux/sys_signal.go | 2 +- pkg/sentry/syscalls/linux/sys_socket.go | 2 +- pkg/sentry/syscalls/linux/sys_stat.go | 2 +- pkg/sentry/syscalls/linux/sys_stat_amd64.go | 2 +- pkg/sentry/syscalls/linux/sys_stat_arm64.go | 2 +- pkg/sentry/syscalls/linux/sys_thread.go | 2 +- pkg/sentry/syscalls/linux/sys_time.go | 2 +- pkg/sentry/syscalls/linux/sys_timer.go | 2 +- pkg/sentry/syscalls/linux/sys_write.go | 2 +- pkg/sentry/syscalls/linux/sys_xattr.go | 2 +- pkg/sentry/syscalls/linux/timespec.go | 2 +- pkg/sentry/unimpl/BUILD | 2 +- pkg/sentry/unimpl/events.go | 2 +- pkg/sentry/uniqueid/BUILD | 2 +- pkg/sentry/uniqueid/context.go | 2 +- pkg/sentry/usermem/BUILD | 55 -- pkg/sentry/usermem/README.md | 31 -- pkg/sentry/usermem/access_type.go | 128 ----- pkg/sentry/usermem/addr.go | 108 ---- pkg/sentry/usermem/addr_range_seq_test.go | 197 ------- pkg/sentry/usermem/addr_range_seq_unsafe.go | 277 --------- pkg/sentry/usermem/bytes_io.go | 141 ----- pkg/sentry/usermem/bytes_io_unsafe.go | 47 -- pkg/sentry/usermem/usermem.go | 597 -------------------- pkg/sentry/usermem/usermem_arm64.go | 53 -- pkg/sentry/usermem/usermem_test.go | 424 -------------- pkg/sentry/usermem/usermem_unsafe.go | 27 - pkg/sentry/usermem/usermem_x86.go | 38 -- pkg/sentry/vfs/BUILD | 10 +- pkg/sentry/vfs/context.go | 2 +- pkg/sentry/vfs/device.go | 2 +- pkg/sentry/vfs/file_description.go | 4 +- pkg/sentry/vfs/file_description_impl_util.go | 4 +- pkg/sentry/vfs/file_description_impl_util_test.go | 6 +- pkg/sentry/vfs/filesystem.go | 2 +- pkg/sentry/vfs/filesystem_type.go | 2 +- pkg/sentry/vfs/mount.go | 2 +- pkg/sentry/vfs/pathname.go | 2 +- pkg/sentry/vfs/testutil.go | 2 +- pkg/sentry/vfs/vfs.go | 2 +- pkg/usermem/BUILD | 55 ++ pkg/usermem/README.md | 31 ++ pkg/usermem/access_type.go | 128 +++++ pkg/usermem/addr.go | 108 ++++ pkg/usermem/addr_range_seq_test.go | 197 +++++++ pkg/usermem/addr_range_seq_unsafe.go | 277 +++++++++ pkg/usermem/bytes_io.go | 141 +++++ pkg/usermem/bytes_io_unsafe.go | 47 ++ pkg/usermem/usermem.go | 597 ++++++++++++++++++++ pkg/usermem/usermem_arm64.go | 53 ++ pkg/usermem/usermem_test.go | 424 ++++++++++++++ pkg/usermem/usermem_unsafe.go | 27 + pkg/usermem/usermem_x86.go | 38 ++ runsc/boot/BUILD | 6 +- runsc/boot/fds.go | 2 +- runsc/boot/fs.go | 2 +- runsc/boot/loader_test.go | 2 +- runsc/boot/user.go | 4 +- runsc/boot/user_test.go | 2 +- tools/go_marshal/defs.bzl | 4 +- tools/go_marshal/gomarshal/generator.go | 4 +- tools/go_marshal/test/BUILD | 2 +- tools/go_marshal/test/benchmark_test.go | 2 +- 483 files changed, 6839 insertions(+), 6835 deletions(-) create mode 100644 pkg/context/BUILD create mode 100644 pkg/context/context.go create mode 100644 pkg/safecopy/BUILD create mode 100644 pkg/safecopy/LICENSE create mode 100644 pkg/safecopy/atomic_amd64.s create mode 100644 pkg/safecopy/atomic_arm64.s create mode 100644 pkg/safecopy/memclr_amd64.s create mode 100644 pkg/safecopy/memclr_arm64.s create mode 100644 pkg/safecopy/memcpy_amd64.s create mode 100644 pkg/safecopy/memcpy_arm64.s create mode 100644 pkg/safecopy/safecopy.go create mode 100644 pkg/safecopy/safecopy_test.go create mode 100644 pkg/safecopy/safecopy_unsafe.go create mode 100644 pkg/safecopy/sighandler_amd64.s create mode 100644 pkg/safecopy/sighandler_arm64.s create mode 100644 pkg/safemem/BUILD create mode 100644 pkg/safemem/block_unsafe.go create mode 100644 pkg/safemem/io.go create mode 100644 pkg/safemem/io_test.go create mode 100644 pkg/safemem/safemem.go create mode 100644 pkg/safemem/seq_test.go create mode 100644 pkg/safemem/seq_unsafe.go delete mode 100644 pkg/sentry/context/BUILD delete mode 100644 pkg/sentry/context/context.go delete mode 100644 pkg/sentry/context/contexttest/BUILD delete mode 100644 pkg/sentry/context/contexttest/contexttest.go create mode 100644 pkg/sentry/contexttest/BUILD create mode 100644 pkg/sentry/contexttest/contexttest.go delete mode 100644 pkg/sentry/platform/safecopy/BUILD delete mode 100644 pkg/sentry/platform/safecopy/LICENSE delete mode 100644 pkg/sentry/platform/safecopy/atomic_amd64.s delete mode 100644 pkg/sentry/platform/safecopy/atomic_arm64.s delete mode 100644 pkg/sentry/platform/safecopy/memclr_amd64.s delete mode 100644 pkg/sentry/platform/safecopy/memclr_arm64.s delete mode 100644 pkg/sentry/platform/safecopy/memcpy_amd64.s delete mode 100644 pkg/sentry/platform/safecopy/memcpy_arm64.s delete mode 100644 pkg/sentry/platform/safecopy/safecopy.go delete mode 100644 pkg/sentry/platform/safecopy/safecopy_test.go delete mode 100644 pkg/sentry/platform/safecopy/safecopy_unsafe.go delete mode 100644 pkg/sentry/platform/safecopy/sighandler_amd64.s delete mode 100644 pkg/sentry/platform/safecopy/sighandler_arm64.s delete mode 100644 pkg/sentry/safemem/BUILD delete mode 100644 pkg/sentry/safemem/block_unsafe.go delete mode 100644 pkg/sentry/safemem/io.go delete mode 100644 pkg/sentry/safemem/io_test.go delete mode 100644 pkg/sentry/safemem/safemem.go delete mode 100644 pkg/sentry/safemem/seq_test.go delete mode 100644 pkg/sentry/safemem/seq_unsafe.go delete mode 100644 pkg/sentry/usermem/BUILD delete mode 100644 pkg/sentry/usermem/README.md delete mode 100644 pkg/sentry/usermem/access_type.go delete mode 100644 pkg/sentry/usermem/addr.go delete mode 100644 pkg/sentry/usermem/addr_range_seq_test.go delete mode 100644 pkg/sentry/usermem/addr_range_seq_unsafe.go delete mode 100644 pkg/sentry/usermem/bytes_io.go delete mode 100644 pkg/sentry/usermem/bytes_io_unsafe.go delete mode 100644 pkg/sentry/usermem/usermem.go delete mode 100644 pkg/sentry/usermem/usermem_arm64.go delete mode 100644 pkg/sentry/usermem/usermem_test.go delete mode 100644 pkg/sentry/usermem/usermem_unsafe.go delete mode 100644 pkg/sentry/usermem/usermem_x86.go create mode 100644 pkg/usermem/BUILD create mode 100644 pkg/usermem/README.md create mode 100644 pkg/usermem/access_type.go create mode 100644 pkg/usermem/addr.go create mode 100644 pkg/usermem/addr_range_seq_test.go create mode 100644 pkg/usermem/addr_range_seq_unsafe.go create mode 100644 pkg/usermem/bytes_io.go create mode 100644 pkg/usermem/bytes_io_unsafe.go create mode 100644 pkg/usermem/usermem.go create mode 100644 pkg/usermem/usermem_arm64.go create mode 100644 pkg/usermem/usermem_test.go create mode 100644 pkg/usermem/usermem_unsafe.go create mode 100644 pkg/usermem/usermem_x86.go (limited to 'pkg/sentry/fsimpl/tmpfs/filesystem.go') diff --git a/pkg/abi/abi.go b/pkg/abi/abi.go index d56c481c9..e6be93c3a 100644 --- a/pkg/abi/abi.go +++ b/pkg/abi/abi.go @@ -39,3 +39,7 @@ func (o OS) String() string { return fmt.Sprintf("OS(%d)", o) } } + +// ABI is an interface that defines OS-specific interactions. +type ABI interface { +} diff --git a/pkg/context/BUILD b/pkg/context/BUILD new file mode 100644 index 000000000..239f31149 --- /dev/null +++ b/pkg/context/BUILD @@ -0,0 +1,13 @@ +load("//tools:defs.bzl", "go_library") + +package(licenses = ["notice"]) + +go_library( + name = "context", + srcs = ["context.go"], + visibility = ["//:sandbox"], + deps = [ + "//pkg/amutex", + "//pkg/log", + ], +) diff --git a/pkg/context/context.go b/pkg/context/context.go new file mode 100644 index 000000000..23e009ef3 --- /dev/null +++ b/pkg/context/context.go @@ -0,0 +1,141 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// Package context defines an internal context type. +// +// The given Context conforms to the standard Go context, but mandates +// additional methods that are specific to the kernel internals. Note however, +// that the Context described by this package carries additional constraints +// regarding concurrent access and retaining beyond the scope of a call. +// +// See the Context type for complete details. +package context + +import ( + "context" + "time" + + "gvisor.dev/gvisor/pkg/amutex" + "gvisor.dev/gvisor/pkg/log" +) + +type contextID int + +// Globally accessible values from a context. These keys are defined in the +// context package to resolve dependency cycles by not requiring the caller to +// import packages usually required to get these information. +const ( + // CtxThreadGroupID is the current thread group ID when a context represents + // a task context. The value is represented as an int32. + CtxThreadGroupID contextID = iota +) + +// ThreadGroupIDFromContext returns the current thread group ID when ctx +// represents a task context. +func ThreadGroupIDFromContext(ctx Context) (tgid int32, ok bool) { + if tgid := ctx.Value(CtxThreadGroupID); tgid != nil { + return tgid.(int32), true + } + return 0, false +} + +// A Context represents a thread of execution (hereafter "goroutine" to reflect +// Go idiosyncrasy). It carries state associated with the goroutine across API +// boundaries. +// +// While Context exists for essentially the same reasons as Go's standard +// context.Context, the standard type represents the state of an operation +// rather than that of a goroutine. This is a critical distinction: +// +// - Unlike context.Context, which "may be passed to functions running in +// different goroutines", it is *not safe* to use the same Context in multiple +// concurrent goroutines. +// +// - It is *not safe* to retain a Context passed to a function beyond the scope +// of that function call. +// +// In both cases, values extracted from the Context should be used instead. +type Context interface { + log.Logger + amutex.Sleeper + context.Context + + // UninterruptibleSleepStart indicates the beginning of an uninterruptible + // sleep state (equivalent to Linux's TASK_UNINTERRUPTIBLE). If deactivate + // is true and the Context represents a Task, the Task's AddressSpace is + // deactivated. + UninterruptibleSleepStart(deactivate bool) + + // UninterruptibleSleepFinish indicates the end of an uninterruptible sleep + // state that was begun by a previous call to UninterruptibleSleepStart. If + // activate is true and the Context represents a Task, the Task's + // AddressSpace is activated. Normally activate is the same value as the + // deactivate parameter passed to UninterruptibleSleepStart. + UninterruptibleSleepFinish(activate bool) +} + +// NoopSleeper is a noop implementation of amutex.Sleeper and UninterruptibleSleep +// methods for anonymous embedding in other types that do not implement sleeps. +type NoopSleeper struct { + amutex.NoopSleeper +} + +// UninterruptibleSleepStart does nothing. +func (NoopSleeper) UninterruptibleSleepStart(bool) {} + +// UninterruptibleSleepFinish does nothing. +func (NoopSleeper) UninterruptibleSleepFinish(bool) {} + +// Deadline returns zero values, meaning no deadline. +func (NoopSleeper) Deadline() (time.Time, bool) { + return time.Time{}, false +} + +// Done returns nil. +func (NoopSleeper) Done() <-chan struct{} { + return nil +} + +// Err returns nil. +func (NoopSleeper) Err() error { + return nil +} + +// logContext implements basic logging. +type logContext struct { + log.Logger + NoopSleeper +} + +// Value implements Context.Value. +func (logContext) Value(key interface{}) interface{} { + return nil +} + +// bgContext is the context returned by context.Background. +var bgContext = &logContext{Logger: log.Log()} + +// Background returns an empty context using the default logger. +// +// Users should be wary of using a Background context. Please tag any use with +// FIXME(b/38173783) and a note to remove this use. +// +// Generally, one should use the Task as their context when available, or avoid +// having to use a context in places where a Task is unavailable. +// +// Using a Background context for tests is fine, as long as no values are +// needed from the context in the tested code paths. +func Background() Context { + return bgContext +} diff --git a/pkg/safecopy/BUILD b/pkg/safecopy/BUILD new file mode 100644 index 000000000..426ef30c9 --- /dev/null +++ b/pkg/safecopy/BUILD @@ -0,0 +1,29 @@ +load("//tools:defs.bzl", "go_library", "go_test") + +package(licenses = ["notice"]) + +go_library( + name = "safecopy", + srcs = [ + "atomic_amd64.s", + "atomic_arm64.s", + "memclr_amd64.s", + "memclr_arm64.s", + "memcpy_amd64.s", + "memcpy_arm64.s", + "safecopy.go", + "safecopy_unsafe.go", + "sighandler_amd64.s", + "sighandler_arm64.s", + ], + visibility = ["//:sandbox"], + deps = ["//pkg/syserror"], +) + +go_test( + name = "safecopy_test", + srcs = [ + "safecopy_test.go", + ], + library = ":safecopy", +) diff --git a/pkg/safecopy/LICENSE b/pkg/safecopy/LICENSE new file mode 100644 index 000000000..6a66aea5e --- /dev/null +++ b/pkg/safecopy/LICENSE @@ -0,0 +1,27 @@ +Copyright (c) 2009 The Go Authors. All rights reserved. + +Redistribution and use in source and binary forms, with or without +modification, are permitted provided that the following conditions are +met: + + * Redistributions of source code must retain the above copyright +notice, this list of conditions and the following disclaimer. + * Redistributions in binary form must reproduce the above +copyright notice, this list of conditions and the following disclaimer +in the documentation and/or other materials provided with the +distribution. + * Neither the name of Google Inc. nor the names of its +contributors may be used to endorse or promote products derived from +this software without specific prior written permission. + +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. diff --git a/pkg/safecopy/atomic_amd64.s b/pkg/safecopy/atomic_amd64.s new file mode 100644 index 000000000..a0cd78f33 --- /dev/null +++ b/pkg/safecopy/atomic_amd64.s @@ -0,0 +1,136 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +#include "textflag.h" + +// handleSwapUint32Fault returns the value stored in DI. Control is transferred +// to it when swapUint32 below receives SIGSEGV or SIGBUS, with the signal +// number stored in DI. +// +// It must have the same frame configuration as swapUint32 so that it can undo +// any potential call frame set up by the assembler. +TEXT handleSwapUint32Fault(SB), NOSPLIT, $0-24 + MOVL DI, sig+20(FP) + RET + +// swapUint32 atomically stores new into *addr and returns (the previous *addr +// value, 0). If a SIGSEGV or SIGBUS signal is received during the swap, the +// value of old is unspecified, and sig is the number of the signal that was +// received. +// +// Preconditions: addr must be aligned to a 4-byte boundary. +// +//func swapUint32(ptr unsafe.Pointer, new uint32) (old uint32, sig int32) +TEXT ·swapUint32(SB), NOSPLIT, $0-24 + // Store 0 as the returned signal number. If we run to completion, + // this is the value the caller will see; if a signal is received, + // handleSwapUint32Fault will store a different value in this address. + MOVL $0, sig+20(FP) + + MOVQ addr+0(FP), DI + MOVL new+8(FP), AX + XCHGL AX, 0(DI) + MOVL AX, old+16(FP) + RET + +// handleSwapUint64Fault returns the value stored in DI. Control is transferred +// to it when swapUint64 below receives SIGSEGV or SIGBUS, with the signal +// number stored in DI. +// +// It must have the same frame configuration as swapUint64 so that it can undo +// any potential call frame set up by the assembler. +TEXT handleSwapUint64Fault(SB), NOSPLIT, $0-28 + MOVL DI, sig+24(FP) + RET + +// swapUint64 atomically stores new into *addr and returns (the previous *addr +// value, 0). If a SIGSEGV or SIGBUS signal is received during the swap, the +// value of old is unspecified, and sig is the number of the signal that was +// received. +// +// Preconditions: addr must be aligned to a 8-byte boundary. +// +//func swapUint64(ptr unsafe.Pointer, new uint64) (old uint64, sig int32) +TEXT ·swapUint64(SB), NOSPLIT, $0-28 + // Store 0 as the returned signal number. If we run to completion, + // this is the value the caller will see; if a signal is received, + // handleSwapUint64Fault will store a different value in this address. + MOVL $0, sig+24(FP) + + MOVQ addr+0(FP), DI + MOVQ new+8(FP), AX + XCHGQ AX, 0(DI) + MOVQ AX, old+16(FP) + RET + +// handleCompareAndSwapUint32Fault returns the value stored in DI. Control is +// transferred to it when swapUint64 below receives SIGSEGV or SIGBUS, with the +// signal number stored in DI. +// +// It must have the same frame configuration as compareAndSwapUint32 so that it +// can undo any potential call frame set up by the assembler. +TEXT handleCompareAndSwapUint32Fault(SB), NOSPLIT, $0-24 + MOVL DI, sig+20(FP) + RET + +// compareAndSwapUint32 is like sync/atomic.CompareAndSwapUint32, but returns +// (the value previously stored at addr, 0). If a SIGSEGV or SIGBUS signal is +// received during the operation, the value of prev is unspecified, and sig is +// the number of the signal that was received. +// +// Preconditions: addr must be aligned to a 4-byte boundary. +// +//func compareAndSwapUint32(ptr unsafe.Pointer, old, new uint32) (prev uint32, sig int32) +TEXT ·compareAndSwapUint32(SB), NOSPLIT, $0-24 + // Store 0 as the returned signal number. If we run to completion, this is + // the value the caller will see; if a signal is received, + // handleCompareAndSwapUint32Fault will store a different value in this + // address. + MOVL $0, sig+20(FP) + + MOVQ addr+0(FP), DI + MOVL old+8(FP), AX + MOVL new+12(FP), DX + LOCK + CMPXCHGL DX, 0(DI) + MOVL AX, prev+16(FP) + RET + +// handleLoadUint32Fault returns the value stored in DI. Control is transferred +// to it when LoadUint32 below receives SIGSEGV or SIGBUS, with the signal +// number stored in DI. +// +// It must have the same frame configuration as loadUint32 so that it can undo +// any potential call frame set up by the assembler. +TEXT handleLoadUint32Fault(SB), NOSPLIT, $0-16 + MOVL DI, sig+12(FP) + RET + +// loadUint32 atomically loads *addr and returns it. If a SIGSEGV or SIGBUS +// signal is received, the value returned is unspecified, and sig is the number +// of the signal that was received. +// +// Preconditions: addr must be aligned to a 4-byte boundary. +// +//func loadUint32(ptr unsafe.Pointer) (val uint32, sig int32) +TEXT ·loadUint32(SB), NOSPLIT, $0-16 + // Store 0 as the returned signal number. If we run to completion, + // this is the value the caller will see; if a signal is received, + // handleLoadUint32Fault will store a different value in this address. + MOVL $0, sig+12(FP) + + MOVQ addr+0(FP), AX + MOVL (AX), BX + MOVL BX, val+8(FP) + RET diff --git a/pkg/safecopy/atomic_arm64.s b/pkg/safecopy/atomic_arm64.s new file mode 100644 index 000000000..d58ed71f7 --- /dev/null +++ b/pkg/safecopy/atomic_arm64.s @@ -0,0 +1,126 @@ +// Copyright 2014 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#include "textflag.h" + +// handleSwapUint32Fault returns the value stored in R1. Control is transferred +// to it when swapUint32 below receives SIGSEGV or SIGBUS, with the signal +// number stored in R1. +// +// It must have the same frame configuration as swapUint32 so that it can undo +// any potential call frame set up by the assembler. +TEXT handleSwapUint32Fault(SB), NOSPLIT, $0-24 + MOVW R1, sig+20(FP) + RET + +// See the corresponding doc in safecopy_unsafe.go +// +// The code is derived from Go source runtime/internal/atomic.Xchg. +// +//func swapUint32(ptr unsafe.Pointer, new uint32) (old uint32, sig int32) +TEXT ·swapUint32(SB), NOSPLIT, $0-24 + // Store 0 as the returned signal number. If we run to completion, + // this is the value the caller will see; if a signal is received, + // handleSwapUint32Fault will store a different value in this address. + MOVW $0, sig+20(FP) +again: + MOVD addr+0(FP), R0 + MOVW new+8(FP), R1 + LDAXRW (R0), R2 + STLXRW R1, (R0), R3 + CBNZ R3, again + MOVW R2, old+16(FP) + RET + +// handleSwapUint64Fault returns the value stored in R1. Control is transferred +// to it when swapUint64 below receives SIGSEGV or SIGBUS, with the signal +// number stored in R1. +// +// It must have the same frame configuration as swapUint64 so that it can undo +// any potential call frame set up by the assembler. +TEXT handleSwapUint64Fault(SB), NOSPLIT, $0-28 + MOVW R1, sig+24(FP) + RET + +// See the corresponding doc in safecopy_unsafe.go +// +// The code is derived from Go source runtime/internal/atomic.Xchg64. +// +//func swapUint64(ptr unsafe.Pointer, new uint64) (old uint64, sig int32) +TEXT ·swapUint64(SB), NOSPLIT, $0-28 + // Store 0 as the returned signal number. If we run to completion, + // this is the value the caller will see; if a signal is received, + // handleSwapUint64Fault will store a different value in this address. + MOVW $0, sig+24(FP) +again: + MOVD addr+0(FP), R0 + MOVD new+8(FP), R1 + LDAXR (R0), R2 + STLXR R1, (R0), R3 + CBNZ R3, again + MOVD R2, old+16(FP) + RET + +// handleCompareAndSwapUint32Fault returns the value stored in R1. Control is +// transferred to it when compareAndSwapUint32 below receives SIGSEGV or SIGBUS, +// with the signal number stored in R1. +// +// It must have the same frame configuration as compareAndSwapUint32 so that it +// can undo any potential call frame set up by the assembler. +TEXT handleCompareAndSwapUint32Fault(SB), NOSPLIT, $0-24 + MOVW R1, sig+20(FP) + RET + +// See the corresponding doc in safecopy_unsafe.go +// +// The code is derived from Go source runtime/internal/atomic.Cas. +// +//func compareAndSwapUint32(ptr unsafe.Pointer, old, new uint32) (prev uint32, sig int32) +TEXT ·compareAndSwapUint32(SB), NOSPLIT, $0-24 + // Store 0 as the returned signal number. If we run to completion, this is + // the value the caller will see; if a signal is received, + // handleCompareAndSwapUint32Fault will store a different value in this + // address. + MOVW $0, sig+20(FP) + + MOVD addr+0(FP), R0 + MOVW old+8(FP), R1 + MOVW new+12(FP), R2 +again: + LDAXRW (R0), R3 + CMPW R1, R3 + BNE done + STLXRW R2, (R0), R4 + CBNZ R4, again +done: + MOVW R3, prev+16(FP) + RET + +// handleLoadUint32Fault returns the value stored in DI. Control is transferred +// to it when LoadUint32 below receives SIGSEGV or SIGBUS, with the signal +// number stored in DI. +// +// It must have the same frame configuration as loadUint32 so that it can undo +// any potential call frame set up by the assembler. +TEXT handleLoadUint32Fault(SB), NOSPLIT, $0-16 + MOVW R1, sig+12(FP) + RET + +// loadUint32 atomically loads *addr and returns it. If a SIGSEGV or SIGBUS +// signal is received, the value returned is unspecified, and sig is the number +// of the signal that was received. +// +// Preconditions: addr must be aligned to a 4-byte boundary. +// +//func loadUint32(ptr unsafe.Pointer) (val uint32, sig int32) +TEXT ·loadUint32(SB), NOSPLIT, $0-16 + // Store 0 as the returned signal number. If we run to completion, + // this is the value the caller will see; if a signal is received, + // handleLoadUint32Fault will store a different value in this address. + MOVW $0, sig+12(FP) + + MOVD addr+0(FP), R0 + LDARW (R0), R1 + MOVW R1, val+8(FP) + RET diff --git a/pkg/safecopy/memclr_amd64.s b/pkg/safecopy/memclr_amd64.s new file mode 100644 index 000000000..64cf32f05 --- /dev/null +++ b/pkg/safecopy/memclr_amd64.s @@ -0,0 +1,147 @@ +// Copyright 2014 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#include "textflag.h" + +// handleMemclrFault returns (the value stored in AX, the value stored in DI). +// Control is transferred to it when memclr below receives SIGSEGV or SIGBUS, +// with the faulting address stored in AX and the signal number stored in DI. +// +// It must have the same frame configuration as memclr so that it can undo any +// potential call frame set up by the assembler. +TEXT handleMemclrFault(SB), NOSPLIT, $0-28 + MOVQ AX, addr+16(FP) + MOVL DI, sig+24(FP) + RET + +// memclr sets the n bytes following ptr to zeroes. If a SIGSEGV or SIGBUS +// signal is received during the write, it returns the address that caused the +// fault and the number of the signal that was received. Otherwise, it returns +// an unspecified address and a signal number of 0. +// +// Data is written in order, such that if a fault happens at address p, it is +// safe to assume that all data before p-maxRegisterSize has already been +// successfully written. +// +// The code is derived from runtime.memclrNoHeapPointers. +// +// func memclr(ptr unsafe.Pointer, n uintptr) (fault unsafe.Pointer, sig int32) +TEXT ·memclr(SB), NOSPLIT, $0-28 + // Store 0 as the returned signal number. If we run to completion, + // this is the value the caller will see; if a signal is received, + // handleMemclrFault will store a different value in this address. + MOVL $0, sig+24(FP) + + MOVQ ptr+0(FP), DI + MOVQ n+8(FP), BX + XORQ AX, AX + + // MOVOU seems always faster than REP STOSQ. +tail: + TESTQ BX, BX + JEQ _0 + CMPQ BX, $2 + JBE _1or2 + CMPQ BX, $4 + JBE _3or4 + CMPQ BX, $8 + JB _5through7 + JE _8 + CMPQ BX, $16 + JBE _9through16 + PXOR X0, X0 + CMPQ BX, $32 + JBE _17through32 + CMPQ BX, $64 + JBE _33through64 + CMPQ BX, $128 + JBE _65through128 + CMPQ BX, $256 + JBE _129through256 + // TODO: use branch table and BSR to make this just a single dispatch + // TODO: for really big clears, use MOVNTDQ, even without AVX2. + +loop: + MOVOU X0, 0(DI) + MOVOU X0, 16(DI) + MOVOU X0, 32(DI) + MOVOU X0, 48(DI) + MOVOU X0, 64(DI) + MOVOU X0, 80(DI) + MOVOU X0, 96(DI) + MOVOU X0, 112(DI) + MOVOU X0, 128(DI) + MOVOU X0, 144(DI) + MOVOU X0, 160(DI) + MOVOU X0, 176(DI) + MOVOU X0, 192(DI) + MOVOU X0, 208(DI) + MOVOU X0, 224(DI) + MOVOU X0, 240(DI) + SUBQ $256, BX + ADDQ $256, DI + CMPQ BX, $256 + JAE loop + JMP tail + +_1or2: + MOVB AX, (DI) + MOVB AX, -1(DI)(BX*1) + RET +_0: + RET +_3or4: + MOVW AX, (DI) + MOVW AX, -2(DI)(BX*1) + RET +_5through7: + MOVL AX, (DI) + MOVL AX, -4(DI)(BX*1) + RET +_8: + // We need a separate case for 8 to make sure we clear pointers atomically. + MOVQ AX, (DI) + RET +_9through16: + MOVQ AX, (DI) + MOVQ AX, -8(DI)(BX*1) + RET +_17through32: + MOVOU X0, (DI) + MOVOU X0, -16(DI)(BX*1) + RET +_33through64: + MOVOU X0, (DI) + MOVOU X0, 16(DI) + MOVOU X0, -32(DI)(BX*1) + MOVOU X0, -16(DI)(BX*1) + RET +_65through128: + MOVOU X0, (DI) + MOVOU X0, 16(DI) + MOVOU X0, 32(DI) + MOVOU X0, 48(DI) + MOVOU X0, -64(DI)(BX*1) + MOVOU X0, -48(DI)(BX*1) + MOVOU X0, -32(DI)(BX*1) + MOVOU X0, -16(DI)(BX*1) + RET +_129through256: + MOVOU X0, (DI) + MOVOU X0, 16(DI) + MOVOU X0, 32(DI) + MOVOU X0, 48(DI) + MOVOU X0, 64(DI) + MOVOU X0, 80(DI) + MOVOU X0, 96(DI) + MOVOU X0, 112(DI) + MOVOU X0, -128(DI)(BX*1) + MOVOU X0, -112(DI)(BX*1) + MOVOU X0, -96(DI)(BX*1) + MOVOU X0, -80(DI)(BX*1) + MOVOU X0, -64(DI)(BX*1) + MOVOU X0, -48(DI)(BX*1) + MOVOU X0, -32(DI)(BX*1) + MOVOU X0, -16(DI)(BX*1) + RET diff --git a/pkg/safecopy/memclr_arm64.s b/pkg/safecopy/memclr_arm64.s new file mode 100644 index 000000000..7361b9067 --- /dev/null +++ b/pkg/safecopy/memclr_arm64.s @@ -0,0 +1,74 @@ +// Copyright 2014 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#include "textflag.h" + +// handleMemclrFault returns (the value stored in R0, the value stored in R1). +// Control is transferred to it when memclr below receives SIGSEGV or SIGBUS, +// with the faulting address stored in R0 and the signal number stored in R1. +// +// It must have the same frame configuration as memclr so that it can undo any +// potential call frame set up by the assembler. +TEXT handleMemclrFault(SB), NOSPLIT, $0-28 + MOVD R0, addr+16(FP) + MOVW R1, sig+24(FP) + RET + +// See the corresponding doc in safecopy_unsafe.go +// +// The code is derived from runtime.memclrNoHeapPointers. +// +// func memclr(ptr unsafe.Pointer, n uintptr) (fault unsafe.Pointer, sig int32) +TEXT ·memclr(SB), NOSPLIT, $0-28 + // Store 0 as the returned signal number. If we run to completion, + // this is the value the caller will see; if a signal is received, + // handleMemclrFault will store a different value in this address. + MOVW $0, sig+24(FP) + MOVD ptr+0(FP), R0 + MOVD n+8(FP), R1 + + // If size is less than 16 bytes, use tail_zero to zero what remains + CMP $16, R1 + BLT tail_zero + // Get buffer offset into 16 byte aligned address for better performance + ANDS $15, R0, ZR + BNE unaligned_to_16 +aligned_to_16: + LSR $4, R1, R2 +zero_by_16: + STP.P (ZR, ZR), 16(R0) // Store pair with post index. + SUBS $1, R2, R2 + BNE zero_by_16 + ANDS $15, R1, R1 + BEQ end + + // Zero buffer with size=R1 < 16 +tail_zero: + TBZ $3, R1, tail_zero_4 + MOVD.P ZR, 8(R0) +tail_zero_4: + TBZ $2, R1, tail_zero_2 + MOVW.P ZR, 4(R0) +tail_zero_2: + TBZ $1, R1, tail_zero_1 + MOVH.P ZR, 2(R0) +tail_zero_1: + TBZ $0, R1, end + MOVB ZR, (R0) +end: + RET + +unaligned_to_16: + MOVD R0, R2 +head_loop: + MOVBU.P ZR, 1(R0) + ANDS $15, R0, ZR + BNE head_loop + // Adjust length for what remains + SUB R2, R0, R3 + SUB R3, R1 + // If size is less than 16 bytes, use tail_zero to zero what remains + CMP $16, R1 + BLT tail_zero + B aligned_to_16 diff --git a/pkg/safecopy/memcpy_amd64.s b/pkg/safecopy/memcpy_amd64.s new file mode 100644 index 000000000..129691d68 --- /dev/null +++ b/pkg/safecopy/memcpy_amd64.s @@ -0,0 +1,250 @@ +// Copyright © 1994-1999 Lucent Technologies Inc. All rights reserved. +// Revisions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com). All rights reserved. +// Portions Copyright 2009 The Go Authors. All rights reserved. +// +// Permission is hereby granted, free of charge, to any person obtaining a copy +// of this software and associated documentation files (the "Software"), to deal +// in the Software without restriction, including without limitation the rights +// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +// copies of the Software, and to permit persons to whom the Software is +// furnished to do so, subject to the following conditions: +// +// The above copyright notice and this permission notice shall be included in +// all copies or substantial portions of the Software. +// +// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN +// THE SOFTWARE. + +#include "textflag.h" + +// handleMemcpyFault returns (the value stored in AX, the value stored in DI). +// Control is transferred to it when memcpy below receives SIGSEGV or SIGBUS, +// with the faulting address stored in AX and the signal number stored in DI. +// +// It must have the same frame configuration as memcpy so that it can undo any +// potential call frame set up by the assembler. +TEXT handleMemcpyFault(SB), NOSPLIT, $0-36 + MOVQ AX, addr+24(FP) + MOVL DI, sig+32(FP) + RET + +// memcpy copies data from src to dst. If a SIGSEGV or SIGBUS signal is received +// during the copy, it returns the address that caused the fault and the number +// of the signal that was received. Otherwise, it returns an unspecified address +// and a signal number of 0. +// +// Data is copied in order, such that if a fault happens at address p, it is +// safe to assume that all data before p-maxRegisterSize has already been +// successfully copied. +// +// The code is derived from the forward copying part of runtime.memmove. +// +// func memcpy(dst, src unsafe.Pointer, n uintptr) (fault unsafe.Pointer, sig int32) +TEXT ·memcpy(SB), NOSPLIT, $0-36 + // Store 0 as the returned signal number. If we run to completion, + // this is the value the caller will see; if a signal is received, + // handleMemcpyFault will store a different value in this address. + MOVL $0, sig+32(FP) + + MOVQ to+0(FP), DI + MOVQ from+8(FP), SI + MOVQ n+16(FP), BX + + // REP instructions have a high startup cost, so we handle small sizes + // with some straightline code. The REP MOVSQ instruction is really fast + // for large sizes. The cutover is approximately 2K. +tail: + // move_129through256 or smaller work whether or not the source and the + // destination memory regions overlap because they load all data into + // registers before writing it back. move_256through2048 on the other + // hand can be used only when the memory regions don't overlap or the copy + // direction is forward. + TESTQ BX, BX + JEQ move_0 + CMPQ BX, $2 + JBE move_1or2 + CMPQ BX, $4 + JBE move_3or4 + CMPQ BX, $8 + JB move_5through7 + JE move_8 + CMPQ BX, $16 + JBE move_9through16 + CMPQ BX, $32 + JBE move_17through32 + CMPQ BX, $64 + JBE move_33through64 + CMPQ BX, $128 + JBE move_65through128 + CMPQ BX, $256 + JBE move_129through256 + // TODO: use branch table and BSR to make this just a single dispatch + +/* + * forward copy loop + */ + CMPQ BX, $2048 + JLS move_256through2048 + + // Check alignment + MOVL SI, AX + ORL DI, AX + TESTL $7, AX + JEQ fwdBy8 + + // Do 1 byte at a time + MOVQ BX, CX + REP; MOVSB + RET + +fwdBy8: + // Do 8 bytes at a time + MOVQ BX, CX + SHRQ $3, CX + ANDQ $7, BX + REP; MOVSQ + JMP tail + +move_1or2: + MOVB (SI), AX + MOVB AX, (DI) + MOVB -1(SI)(BX*1), CX + MOVB CX, -1(DI)(BX*1) + RET +move_0: + RET +move_3or4: + MOVW (SI), AX + MOVW AX, (DI) + MOVW -2(SI)(BX*1), CX + MOVW CX, -2(DI)(BX*1) + RET +move_5through7: + MOVL (SI), AX + MOVL AX, (DI) + MOVL -4(SI)(BX*1), CX + MOVL CX, -4(DI)(BX*1) + RET +move_8: + // We need a separate case for 8 to make sure we write pointers atomically. + MOVQ (SI), AX + MOVQ AX, (DI) + RET +move_9through16: + MOVQ (SI), AX + MOVQ AX, (DI) + MOVQ -8(SI)(BX*1), CX + MOVQ CX, -8(DI)(BX*1) + RET +move_17through32: + MOVOU (SI), X0 + MOVOU X0, (DI) + MOVOU -16(SI)(BX*1), X1 + MOVOU X1, -16(DI)(BX*1) + RET +move_33through64: + MOVOU (SI), X0 + MOVOU X0, (DI) + MOVOU 16(SI), X1 + MOVOU X1, 16(DI) + MOVOU -32(SI)(BX*1), X2 + MOVOU X2, -32(DI)(BX*1) + MOVOU -16(SI)(BX*1), X3 + MOVOU X3, -16(DI)(BX*1) + RET +move_65through128: + MOVOU (SI), X0 + MOVOU X0, (DI) + MOVOU 16(SI), X1 + MOVOU X1, 16(DI) + MOVOU 32(SI), X2 + MOVOU X2, 32(DI) + MOVOU 48(SI), X3 + MOVOU X3, 48(DI) + MOVOU -64(SI)(BX*1), X4 + MOVOU X4, -64(DI)(BX*1) + MOVOU -48(SI)(BX*1), X5 + MOVOU X5, -48(DI)(BX*1) + MOVOU -32(SI)(BX*1), X6 + MOVOU X6, -32(DI)(BX*1) + MOVOU -16(SI)(BX*1), X7 + MOVOU X7, -16(DI)(BX*1) + RET +move_129through256: + MOVOU (SI), X0 + MOVOU X0, (DI) + MOVOU 16(SI), X1 + MOVOU X1, 16(DI) + MOVOU 32(SI), X2 + MOVOU X2, 32(DI) + MOVOU 48(SI), X3 + MOVOU X3, 48(DI) + MOVOU 64(SI), X4 + MOVOU X4, 64(DI) + MOVOU 80(SI), X5 + MOVOU X5, 80(DI) + MOVOU 96(SI), X6 + MOVOU X6, 96(DI) + MOVOU 112(SI), X7 + MOVOU X7, 112(DI) + MOVOU -128(SI)(BX*1), X8 + MOVOU X8, -128(DI)(BX*1) + MOVOU -112(SI)(BX*1), X9 + MOVOU X9, -112(DI)(BX*1) + MOVOU -96(SI)(BX*1), X10 + MOVOU X10, -96(DI)(BX*1) + MOVOU -80(SI)(BX*1), X11 + MOVOU X11, -80(DI)(BX*1) + MOVOU -64(SI)(BX*1), X12 + MOVOU X12, -64(DI)(BX*1) + MOVOU -48(SI)(BX*1), X13 + MOVOU X13, -48(DI)(BX*1) + MOVOU -32(SI)(BX*1), X14 + MOVOU X14, -32(DI)(BX*1) + MOVOU -16(SI)(BX*1), X15 + MOVOU X15, -16(DI)(BX*1) + RET +move_256through2048: + SUBQ $256, BX + MOVOU (SI), X0 + MOVOU X0, (DI) + MOVOU 16(SI), X1 + MOVOU X1, 16(DI) + MOVOU 32(SI), X2 + MOVOU X2, 32(DI) + MOVOU 48(SI), X3 + MOVOU X3, 48(DI) + MOVOU 64(SI), X4 + MOVOU X4, 64(DI) + MOVOU 80(SI), X5 + MOVOU X5, 80(DI) + MOVOU 96(SI), X6 + MOVOU X6, 96(DI) + MOVOU 112(SI), X7 + MOVOU X7, 112(DI) + MOVOU 128(SI), X8 + MOVOU X8, 128(DI) + MOVOU 144(SI), X9 + MOVOU X9, 144(DI) + MOVOU 160(SI), X10 + MOVOU X10, 160(DI) + MOVOU 176(SI), X11 + MOVOU X11, 176(DI) + MOVOU 192(SI), X12 + MOVOU X12, 192(DI) + MOVOU 208(SI), X13 + MOVOU X13, 208(DI) + MOVOU 224(SI), X14 + MOVOU X14, 224(DI) + MOVOU 240(SI), X15 + MOVOU X15, 240(DI) + CMPQ BX, $256 + LEAQ 256(SI), SI + LEAQ 256(DI), DI + JGE move_256through2048 + JMP tail diff --git a/pkg/safecopy/memcpy_arm64.s b/pkg/safecopy/memcpy_arm64.s new file mode 100644 index 000000000..e7e541565 --- /dev/null +++ b/pkg/safecopy/memcpy_arm64.s @@ -0,0 +1,78 @@ +// Copyright 2014 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#include "textflag.h" + +// handleMemcpyFault returns (the value stored in R0, the value stored in R1). +// Control is transferred to it when memcpy below receives SIGSEGV or SIGBUS, +// with the faulting address stored in R0 and the signal number stored in R1. +// +// It must have the same frame configuration as memcpy so that it can undo any +// potential call frame set up by the assembler. +TEXT handleMemcpyFault(SB), NOSPLIT, $0-36 + MOVD R0, addr+24(FP) + MOVW R1, sig+32(FP) + RET + +// memcpy copies data from src to dst. If a SIGSEGV or SIGBUS signal is received +// during the copy, it returns the address that caused the fault and the number +// of the signal that was received. Otherwise, it returns an unspecified address +// and a signal number of 0. +// +// Data is copied in order, such that if a fault happens at address p, it is +// safe to assume that all data before p-maxRegisterSize has already been +// successfully copied. +// +// The code is derived from the Go source runtime.memmove. +// +// func memcpy(dst, src unsafe.Pointer, n uintptr) (fault unsafe.Pointer, sig int32) +TEXT ·memcpy(SB), NOSPLIT, $-8-36 + // Store 0 as the returned signal number. If we run to completion, + // this is the value the caller will see; if a signal is received, + // handleMemcpyFault will store a different value in this address. + MOVW $0, sig+32(FP) + + MOVD to+0(FP), R3 + MOVD from+8(FP), R4 + MOVD n+16(FP), R5 + CMP $0, R5 + BNE check + RET + +check: + AND $~7, R5, R7 // R7 is N&~7. + SUB R7, R5, R6 // R6 is N&7. + + // Copying forward proceeds by copying R7/8 words then copying R6 bytes. + // R3 and R4 are advanced as we copy. + + // (There may be implementations of armv8 where copying by bytes until + // at least one of source or dest is word aligned is a worthwhile + // optimization, but the on the one tested so far (xgene) it did not + // make a significance difference.) + + CMP $0, R7 // Do we need to do any word-by-word copying? + BEQ noforwardlarge + ADD R3, R7, R9 // R9 points just past where we copy by word. + +forwardlargeloop: + MOVD.P 8(R4), R8 // R8 is just a scratch register. + MOVD.P R8, 8(R3) + CMP R3, R9 + BNE forwardlargeloop + +noforwardlarge: + CMP $0, R6 // Do we need to do any byte-by-byte copying? + BNE forwardtail + RET + +forwardtail: + ADD R3, R6, R9 // R9 points just past the destination memory. + +forwardtailloop: + MOVBU.P 1(R4), R8 + MOVBU.P R8, 1(R3) + CMP R3, R9 + BNE forwardtailloop + RET diff --git a/pkg/safecopy/safecopy.go b/pkg/safecopy/safecopy.go new file mode 100644 index 000000000..2fb7e5809 --- /dev/null +++ b/pkg/safecopy/safecopy.go @@ -0,0 +1,144 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// Package safecopy provides an efficient implementation of functions to access +// memory that may result in SIGSEGV or SIGBUS being sent to the accessor. +package safecopy + +import ( + "fmt" + "reflect" + "runtime" + "syscall" + + "gvisor.dev/gvisor/pkg/syserror" +) + +// SegvError is returned when a safecopy function receives SIGSEGV. +type SegvError struct { + // Addr is the address at which the SIGSEGV occurred. + Addr uintptr +} + +// Error implements error.Error. +func (e SegvError) Error() string { + return fmt.Sprintf("SIGSEGV at %#x", e.Addr) +} + +// BusError is returned when a safecopy function receives SIGBUS. +type BusError struct { + // Addr is the address at which the SIGBUS occurred. + Addr uintptr +} + +// Error implements error.Error. +func (e BusError) Error() string { + return fmt.Sprintf("SIGBUS at %#x", e.Addr) +} + +// AlignmentError is returned when a safecopy function is passed an address +// that does not meet alignment requirements. +type AlignmentError struct { + // Addr is the invalid address. + Addr uintptr + + // Alignment is the required alignment. + Alignment uintptr +} + +// Error implements error.Error. +func (e AlignmentError) Error() string { + return fmt.Sprintf("address %#x is not aligned to a %d-byte boundary", e.Addr, e.Alignment) +} + +var ( + // The begin and end addresses below are for the functions that are + // checked by the signal handler. + memcpyBegin uintptr + memcpyEnd uintptr + memclrBegin uintptr + memclrEnd uintptr + swapUint32Begin uintptr + swapUint32End uintptr + swapUint64Begin uintptr + swapUint64End uintptr + compareAndSwapUint32Begin uintptr + compareAndSwapUint32End uintptr + loadUint32Begin uintptr + loadUint32End uintptr + + // savedSigSegVHandler is a pointer to the SIGSEGV handler that was + // configured before we replaced it with our own. We still call into it + // when we get a SIGSEGV that is not interesting to us. + savedSigSegVHandler uintptr + + // same a above, but for SIGBUS signals. + savedSigBusHandler uintptr +) + +// signalHandler is our replacement signal handler for SIGSEGV and SIGBUS +// signals. +func signalHandler() + +// FindEndAddress returns the end address (one byte beyond the last) of the +// function that contains the specified address (begin). +func FindEndAddress(begin uintptr) uintptr { + f := runtime.FuncForPC(begin) + if f != nil { + for p := begin; ; p++ { + g := runtime.FuncForPC(p) + if f != g { + return p + } + } + } + return begin +} + +// initializeAddresses initializes the addresses used by the signal handler. +func initializeAddresses() { + // The following functions are written in assembly language, so they won't + // be inlined by the existing compiler/linker. Tests will fail if this + // assumption is violated. + memcpyBegin = reflect.ValueOf(memcpy).Pointer() + memcpyEnd = FindEndAddress(memcpyBegin) + memclrBegin = reflect.ValueOf(memclr).Pointer() + memclrEnd = FindEndAddress(memclrBegin) + swapUint32Begin = reflect.ValueOf(swapUint32).Pointer() + swapUint32End = FindEndAddress(swapUint32Begin) + swapUint64Begin = reflect.ValueOf(swapUint64).Pointer() + swapUint64End = FindEndAddress(swapUint64Begin) + compareAndSwapUint32Begin = reflect.ValueOf(compareAndSwapUint32).Pointer() + compareAndSwapUint32End = FindEndAddress(compareAndSwapUint32Begin) + loadUint32Begin = reflect.ValueOf(loadUint32).Pointer() + loadUint32End = FindEndAddress(loadUint32Begin) +} + +func init() { + initializeAddresses() + if err := ReplaceSignalHandler(syscall.SIGSEGV, reflect.ValueOf(signalHandler).Pointer(), &savedSigSegVHandler); err != nil { + panic(fmt.Sprintf("Unable to set handler for SIGSEGV: %v", err)) + } + if err := ReplaceSignalHandler(syscall.SIGBUS, reflect.ValueOf(signalHandler).Pointer(), &savedSigBusHandler); err != nil { + panic(fmt.Sprintf("Unable to set handler for SIGBUS: %v", err)) + } + syserror.AddErrorUnwrapper(func(e error) (syscall.Errno, bool) { + switch e.(type) { + case SegvError, BusError, AlignmentError: + return syscall.EFAULT, true + default: + return 0, false + } + }) +} diff --git a/pkg/safecopy/safecopy_test.go b/pkg/safecopy/safecopy_test.go new file mode 100644 index 000000000..5818f7f9b --- /dev/null +++ b/pkg/safecopy/safecopy_test.go @@ -0,0 +1,617 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package safecopy + +import ( + "bytes" + "fmt" + "io/ioutil" + "math/rand" + "os" + "runtime/debug" + "syscall" + "testing" + "unsafe" +) + +// Size of a page in bytes. Cloned from usermem.PageSize to avoid a circular +// dependency. +const pageSize = 4096 + +func initRandom(b []byte) { + for i := range b { + b[i] = byte(rand.Intn(256)) + } +} + +func randBuf(size int) []byte { + b := make([]byte, size) + initRandom(b) + return b +} + +func TestCopyInSuccess(t *testing.T) { + // Test that CopyIn does not return an error when all pages are accessible. + const bufLen = 8192 + a := randBuf(bufLen) + b := make([]byte, bufLen) + + n, err := CopyIn(b, unsafe.Pointer(&a[0])) + if n != bufLen { + t.Errorf("Unexpected copy length, got %v, want %v", n, bufLen) + } + if err != nil { + t.Errorf("Unexpected error: %v", err) + } + if !bytes.Equal(a, b) { + t.Errorf("Buffers are not equal when they should be: %v %v", a, b) + } +} + +func TestCopyOutSuccess(t *testing.T) { + // Test that CopyOut does not return an error when all pages are + // accessible. + const bufLen = 8192 + a := randBuf(bufLen) + b := make([]byte, bufLen) + + n, err := CopyOut(unsafe.Pointer(&b[0]), a) + if n != bufLen { + t.Errorf("Unexpected copy length, got %v, want %v", n, bufLen) + } + if err != nil { + t.Errorf("Unexpected error: %v", err) + } + if !bytes.Equal(a, b) { + t.Errorf("Buffers are not equal when they should be: %v %v", a, b) + } +} + +func TestCopySuccess(t *testing.T) { + // Test that Copy does not return an error when all pages are accessible. + const bufLen = 8192 + a := randBuf(bufLen) + b := make([]byte, bufLen) + + n, err := Copy(unsafe.Pointer(&b[0]), unsafe.Pointer(&a[0]), bufLen) + if n != bufLen { + t.Errorf("Unexpected copy length, got %v, want %v", n, bufLen) + } + if err != nil { + t.Errorf("Unexpected error: %v", err) + } + if !bytes.Equal(a, b) { + t.Errorf("Buffers are not equal when they should be: %v %v", a, b) + } +} + +func TestZeroOutSuccess(t *testing.T) { + // Test that ZeroOut does not return an error when all pages are + // accessible. + const bufLen = 8192 + a := make([]byte, bufLen) + b := randBuf(bufLen) + + n, err := ZeroOut(unsafe.Pointer(&b[0]), bufLen) + if n != bufLen { + t.Errorf("Unexpected copy length, got %v, want %v", n, bufLen) + } + if err != nil { + t.Errorf("Unexpected error: %v", err) + } + if !bytes.Equal(a, b) { + t.Errorf("Buffers are not equal when they should be: %v %v", a, b) + } +} + +func TestSwapUint32Success(t *testing.T) { + // Test that SwapUint32 does not return an error when the page is + // accessible. + before := uint32(rand.Int31()) + after := uint32(rand.Int31()) + val := before + + old, err := SwapUint32(unsafe.Pointer(&val), after) + if err != nil { + t.Errorf("Unexpected error: %v", err) + } + if old != before { + t.Errorf("Unexpected old value: got %v, want %v", old, before) + } + if val != after { + t.Errorf("Unexpected new value: got %v, want %v", val, after) + } +} + +func TestSwapUint32AlignmentError(t *testing.T) { + // Test that SwapUint32 returns an AlignmentError when passed an unaligned + // address. + data := new(struct{ val uint64 }) + addr := uintptr(unsafe.Pointer(&data.val)) + 1 + want := AlignmentError{Addr: addr, Alignment: 4} + if _, err := SwapUint32(unsafe.Pointer(addr), 1); err != want { + t.Errorf("Unexpected error: got %v, want %v", err, want) + } +} + +func TestSwapUint64Success(t *testing.T) { + // Test that SwapUint64 does not return an error when the page is + // accessible. + before := uint64(rand.Int63()) + after := uint64(rand.Int63()) + // "The first word in ... an allocated struct or slice can be relied upon + // to be 64-bit aligned." - sync/atomic docs + data := new(struct{ val uint64 }) + data.val = before + + old, err := SwapUint64(unsafe.Pointer(&data.val), after) + if err != nil { + t.Errorf("Unexpected error: %v", err) + } + if old != before { + t.Errorf("Unexpected old value: got %v, want %v", old, before) + } + if data.val != after { + t.Errorf("Unexpected new value: got %v, want %v", data.val, after) + } +} + +func TestSwapUint64AlignmentError(t *testing.T) { + // Test that SwapUint64 returns an AlignmentError when passed an unaligned + // address. + data := new(struct{ val1, val2 uint64 }) + addr := uintptr(unsafe.Pointer(&data.val1)) + 1 + want := AlignmentError{Addr: addr, Alignment: 8} + if _, err := SwapUint64(unsafe.Pointer(addr), 1); err != want { + t.Errorf("Unexpected error: got %v, want %v", err, want) + } +} + +func TestCompareAndSwapUint32Success(t *testing.T) { + // Test that CompareAndSwapUint32 does not return an error when the page is + // accessible. + before := uint32(rand.Int31()) + after := uint32(rand.Int31()) + val := before + + old, err := CompareAndSwapUint32(unsafe.Pointer(&val), before, after) + if err != nil { + t.Errorf("Unexpected error: %v", err) + } + if old != before { + t.Errorf("Unexpected old value: got %v, want %v", old, before) + } + if val != after { + t.Errorf("Unexpected new value: got %v, want %v", val, after) + } +} + +func TestCompareAndSwapUint32AlignmentError(t *testing.T) { + // Test that CompareAndSwapUint32 returns an AlignmentError when passed an + // unaligned address. + data := new(struct{ val uint64 }) + addr := uintptr(unsafe.Pointer(&data.val)) + 1 + want := AlignmentError{Addr: addr, Alignment: 4} + if _, err := CompareAndSwapUint32(unsafe.Pointer(addr), 0, 1); err != want { + t.Errorf("Unexpected error: got %v, want %v", err, want) + } +} + +// withSegvErrorTestMapping calls fn with a two-page mapping. The first page +// contains random data, and the second page generates SIGSEGV when accessed. +func withSegvErrorTestMapping(t *testing.T, fn func(m []byte)) { + mapping, err := syscall.Mmap(-1, 0, 2*pageSize, syscall.PROT_READ|syscall.PROT_WRITE, syscall.MAP_ANONYMOUS|syscall.MAP_PRIVATE) + if err != nil { + t.Fatalf("Mmap failed: %v", err) + } + defer syscall.Munmap(mapping) + if err := syscall.Mprotect(mapping[pageSize:], syscall.PROT_NONE); err != nil { + t.Fatalf("Mprotect failed: %v", err) + } + initRandom(mapping[:pageSize]) + + fn(mapping) +} + +// withBusErrorTestMapping calls fn with a two-page mapping. The first page +// contains random data, and the second page generates SIGBUS when accessed. +func withBusErrorTestMapping(t *testing.T, fn func(m []byte)) { + f, err := ioutil.TempFile("", "sigbus_test") + if err != nil { + t.Fatalf("TempFile failed: %v", err) + } + defer f.Close() + if err := f.Truncate(pageSize); err != nil { + t.Fatalf("Truncate failed: %v", err) + } + mapping, err := syscall.Mmap(int(f.Fd()), 0, 2*pageSize, syscall.PROT_READ|syscall.PROT_WRITE, syscall.MAP_SHARED) + if err != nil { + t.Fatalf("Mmap failed: %v", err) + } + defer syscall.Munmap(mapping) + initRandom(mapping[:pageSize]) + + fn(mapping) +} + +func TestCopyInSegvError(t *testing.T) { + // Test that CopyIn returns a SegvError when reaching a page that signals + // SIGSEGV. + for bytesBeforeFault := 0; bytesBeforeFault <= 2*maxRegisterSize; bytesBeforeFault++ { + t.Run(fmt.Sprintf("starting copy %d bytes before SIGSEGV", bytesBeforeFault), func(t *testing.T) { + withSegvErrorTestMapping(t, func(mapping []byte) { + secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize + src := unsafe.Pointer(secondPage - uintptr(bytesBeforeFault)) + dst := randBuf(pageSize) + n, err := CopyIn(dst, src) + if n != bytesBeforeFault { + t.Errorf("Unexpected copy length: got %v, want %v", n, bytesBeforeFault) + } + if want := (SegvError{secondPage}); err != want { + t.Errorf("Unexpected error: got %v, want %v", err, want) + } + if got, want := dst[:bytesBeforeFault], mapping[pageSize-bytesBeforeFault:pageSize]; !bytes.Equal(got, want) { + t.Errorf("Buffers are not equal when they should be: %v %v", got, want) + } + }) + }) + } +} + +func TestCopyInBusError(t *testing.T) { + // Test that CopyIn returns a BusError when reaching a page that signals + // SIGBUS. + for bytesBeforeFault := 0; bytesBeforeFault <= 2*maxRegisterSize; bytesBeforeFault++ { + t.Run(fmt.Sprintf("starting copy %d bytes before SIGBUS", bytesBeforeFault), func(t *testing.T) { + withBusErrorTestMapping(t, func(mapping []byte) { + secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize + src := unsafe.Pointer(secondPage - uintptr(bytesBeforeFault)) + dst := randBuf(pageSize) + n, err := CopyIn(dst, src) + if n != bytesBeforeFault { + t.Errorf("Unexpected copy length: got %v, want %v", n, bytesBeforeFault) + } + if want := (BusError{secondPage}); err != want { + t.Errorf("Unexpected error: got %v, want %v", err, want) + } + if got, want := dst[:bytesBeforeFault], mapping[pageSize-bytesBeforeFault:pageSize]; !bytes.Equal(got, want) { + t.Errorf("Buffers are not equal when they should be: %v %v", got, want) + } + }) + }) + } +} + +func TestCopyOutSegvError(t *testing.T) { + // Test that CopyOut returns a SegvError when reaching a page that signals + // SIGSEGV. + for bytesBeforeFault := 0; bytesBeforeFault <= 2*maxRegisterSize; bytesBeforeFault++ { + t.Run(fmt.Sprintf("starting copy %d bytes before SIGSEGV", bytesBeforeFault), func(t *testing.T) { + withSegvErrorTestMapping(t, func(mapping []byte) { + secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize + dst := unsafe.Pointer(secondPage - uintptr(bytesBeforeFault)) + src := randBuf(pageSize) + n, err := CopyOut(dst, src) + if n != bytesBeforeFault { + t.Errorf("Unexpected copy length: got %v, want %v", n, bytesBeforeFault) + } + if want := (SegvError{secondPage}); err != want { + t.Errorf("Unexpected error: got %v, want %v", err, want) + } + if got, want := mapping[pageSize-bytesBeforeFault:pageSize], src[:bytesBeforeFault]; !bytes.Equal(got, want) { + t.Errorf("Buffers are not equal when they should be: %v %v", got, want) + } + }) + }) + } +} + +func TestCopyOutBusError(t *testing.T) { + // Test that CopyOut returns a BusError when reaching a page that signals + // SIGBUS. + for bytesBeforeFault := 0; bytesBeforeFault <= 2*maxRegisterSize; bytesBeforeFault++ { + t.Run(fmt.Sprintf("starting copy %d bytes before SIGSEGV", bytesBeforeFault), func(t *testing.T) { + withBusErrorTestMapping(t, func(mapping []byte) { + secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize + dst := unsafe.Pointer(secondPage - uintptr(bytesBeforeFault)) + src := randBuf(pageSize) + n, err := CopyOut(dst, src) + if n != bytesBeforeFault { + t.Errorf("Unexpected copy length: got %v, want %v", n, bytesBeforeFault) + } + if want := (BusError{secondPage}); err != want { + t.Errorf("Unexpected error: got %v, want %v", err, want) + } + if got, want := mapping[pageSize-bytesBeforeFault:pageSize], src[:bytesBeforeFault]; !bytes.Equal(got, want) { + t.Errorf("Buffers are not equal when they should be: %v %v", got, want) + } + }) + }) + } +} + +func TestCopySourceSegvError(t *testing.T) { + // Test that Copy returns a SegvError when copying from a page that signals + // SIGSEGV. + for bytesBeforeFault := 0; bytesBeforeFault <= 2*maxRegisterSize; bytesBeforeFault++ { + t.Run(fmt.Sprintf("starting copy %d bytes before SIGSEGV", bytesBeforeFault), func(t *testing.T) { + withSegvErrorTestMapping(t, func(mapping []byte) { + secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize + src := unsafe.Pointer(secondPage - uintptr(bytesBeforeFault)) + dst := randBuf(pageSize) + n, err := Copy(unsafe.Pointer(&dst[0]), src, pageSize) + if n != uintptr(bytesBeforeFault) { + t.Errorf("Unexpected copy length: got %v, want %v", n, bytesBeforeFault) + } + if want := (SegvError{secondPage}); err != want { + t.Errorf("Unexpected error: got %v, want %v", err, want) + } + if got, want := dst[:bytesBeforeFault], mapping[pageSize-bytesBeforeFault:pageSize]; !bytes.Equal(got, want) { + t.Errorf("Buffers are not equal when they should be: %v %v", got, want) + } + }) + }) + } +} + +func TestCopySourceBusError(t *testing.T) { + // Test that Copy returns a BusError when copying from a page that signals + // SIGBUS. + for bytesBeforeFault := 0; bytesBeforeFault <= 2*maxRegisterSize; bytesBeforeFault++ { + t.Run(fmt.Sprintf("starting copy %d bytes before SIGBUS", bytesBeforeFault), func(t *testing.T) { + withBusErrorTestMapping(t, func(mapping []byte) { + secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize + src := unsafe.Pointer(secondPage - uintptr(bytesBeforeFault)) + dst := randBuf(pageSize) + n, err := Copy(unsafe.Pointer(&dst[0]), src, pageSize) + if n != uintptr(bytesBeforeFault) { + t.Errorf("Unexpected copy length: got %v, want %v", n, bytesBeforeFault) + } + if want := (BusError{secondPage}); err != want { + t.Errorf("Unexpected error: got %v, want %v", err, want) + } + if got, want := dst[:bytesBeforeFault], mapping[pageSize-bytesBeforeFault:pageSize]; !bytes.Equal(got, want) { + t.Errorf("Buffers are not equal when they should be: %v %v", got, want) + } + }) + }) + } +} + +func TestCopyDestinationSegvError(t *testing.T) { + // Test that Copy returns a SegvError when copying to a page that signals + // SIGSEGV. + for bytesBeforeFault := 0; bytesBeforeFault <= 2*maxRegisterSize; bytesBeforeFault++ { + t.Run(fmt.Sprintf("starting copy %d bytes before SIGSEGV", bytesBeforeFault), func(t *testing.T) { + withSegvErrorTestMapping(t, func(mapping []byte) { + secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize + dst := unsafe.Pointer(secondPage - uintptr(bytesBeforeFault)) + src := randBuf(pageSize) + n, err := Copy(dst, unsafe.Pointer(&src[0]), pageSize) + if n != uintptr(bytesBeforeFault) { + t.Errorf("Unexpected copy length: got %v, want %v", n, bytesBeforeFault) + } + if want := (SegvError{secondPage}); err != want { + t.Errorf("Unexpected error: got %v, want %v", err, want) + } + if got, want := mapping[pageSize-bytesBeforeFault:pageSize], src[:bytesBeforeFault]; !bytes.Equal(got, want) { + t.Errorf("Buffers are not equal when they should be: %v %v", got, want) + } + }) + }) + } +} + +func TestCopyDestinationBusError(t *testing.T) { + // Test that Copy returns a BusError when copying to a page that signals + // SIGBUS. + for bytesBeforeFault := 0; bytesBeforeFault <= 2*maxRegisterSize; bytesBeforeFault++ { + t.Run(fmt.Sprintf("starting copy %d bytes before SIGBUS", bytesBeforeFault), func(t *testing.T) { + withBusErrorTestMapping(t, func(mapping []byte) { + secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize + dst := unsafe.Pointer(secondPage - uintptr(bytesBeforeFault)) + src := randBuf(pageSize) + n, err := Copy(dst, unsafe.Pointer(&src[0]), pageSize) + if n != uintptr(bytesBeforeFault) { + t.Errorf("Unexpected copy length: got %v, want %v", n, bytesBeforeFault) + } + if want := (BusError{secondPage}); err != want { + t.Errorf("Unexpected error: got %v, want %v", err, want) + } + if got, want := mapping[pageSize-bytesBeforeFault:pageSize], src[:bytesBeforeFault]; !bytes.Equal(got, want) { + t.Errorf("Buffers are not equal when they should be: %v %v", got, want) + } + }) + }) + } +} + +func TestZeroOutSegvError(t *testing.T) { + // Test that ZeroOut returns a SegvError when reaching a page that signals + // SIGSEGV. + for bytesBeforeFault := 0; bytesBeforeFault <= 2*maxRegisterSize; bytesBeforeFault++ { + t.Run(fmt.Sprintf("starting write %d bytes before SIGSEGV", bytesBeforeFault), func(t *testing.T) { + withSegvErrorTestMapping(t, func(mapping []byte) { + secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize + dst := unsafe.Pointer(secondPage - uintptr(bytesBeforeFault)) + n, err := ZeroOut(dst, pageSize) + if n != uintptr(bytesBeforeFault) { + t.Errorf("Unexpected write length: got %v, want %v", n, bytesBeforeFault) + } + if want := (SegvError{secondPage}); err != want { + t.Errorf("Unexpected error: got %v, want %v", err, want) + } + if got, want := mapping[pageSize-bytesBeforeFault:pageSize], make([]byte, bytesBeforeFault); !bytes.Equal(got, want) { + t.Errorf("Non-zero bytes in written part of mapping: %v", got) + } + }) + }) + } +} + +func TestZeroOutBusError(t *testing.T) { + // Test that ZeroOut returns a BusError when reaching a page that signals + // SIGBUS. + for bytesBeforeFault := 0; bytesBeforeFault <= 2*maxRegisterSize; bytesBeforeFault++ { + t.Run(fmt.Sprintf("starting write %d bytes before SIGBUS", bytesBeforeFault), func(t *testing.T) { + withBusErrorTestMapping(t, func(mapping []byte) { + secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize + dst := unsafe.Pointer(secondPage - uintptr(bytesBeforeFault)) + n, err := ZeroOut(dst, pageSize) + if n != uintptr(bytesBeforeFault) { + t.Errorf("Unexpected write length: got %v, want %v", n, bytesBeforeFault) + } + if want := (BusError{secondPage}); err != want { + t.Errorf("Unexpected error: got %v, want %v", err, want) + } + if got, want := mapping[pageSize-bytesBeforeFault:pageSize], make([]byte, bytesBeforeFault); !bytes.Equal(got, want) { + t.Errorf("Non-zero bytes in written part of mapping: %v", got) + } + }) + }) + } +} + +func TestSwapUint32SegvError(t *testing.T) { + // Test that SwapUint32 returns a SegvError when reaching a page that + // signals SIGSEGV. + withSegvErrorTestMapping(t, func(mapping []byte) { + secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize + _, err := SwapUint32(unsafe.Pointer(secondPage), 1) + if want := (SegvError{secondPage}); err != want { + t.Errorf("Unexpected error: got %v, want %v", err, want) + } + }) +} + +func TestSwapUint32BusError(t *testing.T) { + // Test that SwapUint32 returns a BusError when reaching a page that + // signals SIGBUS. + withBusErrorTestMapping(t, func(mapping []byte) { + secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize + _, err := SwapUint32(unsafe.Pointer(secondPage), 1) + if want := (BusError{secondPage}); err != want { + t.Errorf("Unexpected error: got %v, want %v", err, want) + } + }) +} + +func TestSwapUint64SegvError(t *testing.T) { + // Test that SwapUint64 returns a SegvError when reaching a page that + // signals SIGSEGV. + withSegvErrorTestMapping(t, func(mapping []byte) { + secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize + _, err := SwapUint64(unsafe.Pointer(secondPage), 1) + if want := (SegvError{secondPage}); err != want { + t.Errorf("Unexpected error: got %v, want %v", err, want) + } + }) +} + +func TestSwapUint64BusError(t *testing.T) { + // Test that SwapUint64 returns a BusError when reaching a page that + // signals SIGBUS. + withBusErrorTestMapping(t, func(mapping []byte) { + secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize + _, err := SwapUint64(unsafe.Pointer(secondPage), 1) + if want := (BusError{secondPage}); err != want { + t.Errorf("Unexpected error: got %v, want %v", err, want) + } + }) +} + +func TestCompareAndSwapUint32SegvError(t *testing.T) { + // Test that CompareAndSwapUint32 returns a SegvError when reaching a page + // that signals SIGSEGV. + withSegvErrorTestMapping(t, func(mapping []byte) { + secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize + _, err := CompareAndSwapUint32(unsafe.Pointer(secondPage), 0, 1) + if want := (SegvError{secondPage}); err != want { + t.Errorf("Unexpected error: got %v, want %v", err, want) + } + }) +} + +func TestCompareAndSwapUint32BusError(t *testing.T) { + // Test that CompareAndSwapUint32 returns a BusError when reaching a page + // that signals SIGBUS. + withBusErrorTestMapping(t, func(mapping []byte) { + secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize + _, err := CompareAndSwapUint32(unsafe.Pointer(secondPage), 0, 1) + if want := (BusError{secondPage}); err != want { + t.Errorf("Unexpected error: got %v, want %v", err, want) + } + }) +} + +func testCopy(dst, src []byte) (panicked bool) { + defer func() { + if r := recover(); r != nil { + panicked = true + } + }() + debug.SetPanicOnFault(true) + copy(dst, src) + return +} + +func TestSegVOnMemmove(t *testing.T) { + // Test that SIGSEGVs received by runtime.memmove when *not* doing + // CopyIn or CopyOut work gets propagated to the runtime. + const bufLen = pageSize + a, err := syscall.Mmap(-1, 0, bufLen, syscall.PROT_NONE, syscall.MAP_ANON|syscall.MAP_PRIVATE) + if err != nil { + t.Fatalf("Mmap failed: %v", err) + + } + defer syscall.Munmap(a) + b := randBuf(bufLen) + + if !testCopy(b, a) { + t.Fatalf("testCopy didn't panic when it should have") + } + + if !testCopy(a, b) { + t.Fatalf("testCopy didn't panic when it should have") + } +} + +func TestSigbusOnMemmove(t *testing.T) { + // Test that SIGBUS received by runtime.memmove when *not* doing + // CopyIn or CopyOut work gets propagated to the runtime. + const bufLen = pageSize + f, err := ioutil.TempFile("", "sigbus_test") + if err != nil { + t.Fatalf("TempFile failed: %v", err) + } + os.Remove(f.Name()) + defer f.Close() + + a, err := syscall.Mmap(int(f.Fd()), 0, bufLen, syscall.PROT_READ|syscall.PROT_WRITE, syscall.MAP_SHARED) + if err != nil { + t.Fatalf("Mmap failed: %v", err) + + } + defer syscall.Munmap(a) + b := randBuf(bufLen) + + if !testCopy(b, a) { + t.Fatalf("testCopy didn't panic when it should have") + } + + if !testCopy(a, b) { + t.Fatalf("testCopy didn't panic when it should have") + } +} diff --git a/pkg/safecopy/safecopy_unsafe.go b/pkg/safecopy/safecopy_unsafe.go new file mode 100644 index 000000000..eef028e68 --- /dev/null +++ b/pkg/safecopy/safecopy_unsafe.go @@ -0,0 +1,335 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package safecopy + +import ( + "fmt" + "syscall" + "unsafe" +) + +// maxRegisterSize is the maximum register size used in memcpy and memclr. It +// is used to decide by how much to rewind the copy (for memcpy) or zeroing +// (for memclr) before proceeding. +const maxRegisterSize = 16 + +// memcpy copies data from src to dst. If a SIGSEGV or SIGBUS signal is received +// during the copy, it returns the address that caused the fault and the number +// of the signal that was received. Otherwise, it returns an unspecified address +// and a signal number of 0. +// +// Data is copied in order, such that if a fault happens at address p, it is +// safe to assume that all data before p-maxRegisterSize has already been +// successfully copied. +// +//go:noescape +func memcpy(dst, src unsafe.Pointer, n uintptr) (fault unsafe.Pointer, sig int32) + +// memclr sets the n bytes following ptr to zeroes. If a SIGSEGV or SIGBUS +// signal is received during the write, it returns the address that caused the +// fault and the number of the signal that was received. Otherwise, it returns +// an unspecified address and a signal number of 0. +// +// Data is written in order, such that if a fault happens at address p, it is +// safe to assume that all data before p-maxRegisterSize has already been +// successfully written. +// +//go:noescape +func memclr(ptr unsafe.Pointer, n uintptr) (fault unsafe.Pointer, sig int32) + +// swapUint32 atomically stores new into *ptr and returns (the previous *ptr +// value, 0). If a SIGSEGV or SIGBUS signal is received during the swap, the +// value of old is unspecified, and sig is the number of the signal that was +// received. +// +// Preconditions: ptr must be aligned to a 4-byte boundary. +// +//go:noescape +func swapUint32(ptr unsafe.Pointer, new uint32) (old uint32, sig int32) + +// swapUint64 atomically stores new into *ptr and returns (the previous *ptr +// value, 0). If a SIGSEGV or SIGBUS signal is received during the swap, the +// value of old is unspecified, and sig is the number of the signal that was +// received. +// +// Preconditions: ptr must be aligned to a 8-byte boundary. +// +//go:noescape +func swapUint64(ptr unsafe.Pointer, new uint64) (old uint64, sig int32) + +// compareAndSwapUint32 is like sync/atomic.CompareAndSwapUint32, but returns +// (the value previously stored at ptr, 0). If a SIGSEGV or SIGBUS signal is +// received during the operation, the value of prev is unspecified, and sig is +// the number of the signal that was received. +// +// Preconditions: ptr must be aligned to a 4-byte boundary. +// +//go:noescape +func compareAndSwapUint32(ptr unsafe.Pointer, old, new uint32) (prev uint32, sig int32) + +// LoadUint32 is like sync/atomic.LoadUint32, but operates with user memory. It +// may fail with SIGSEGV or SIGBUS if it is received while reading from ptr. +// +// Preconditions: ptr must be aligned to a 4-byte boundary. +// +//go:noescape +func loadUint32(ptr unsafe.Pointer) (val uint32, sig int32) + +// CopyIn copies len(dst) bytes from src to dst. It returns the number of bytes +// copied and an error if SIGSEGV or SIGBUS is received while reading from src. +func CopyIn(dst []byte, src unsafe.Pointer) (int, error) { + toCopy := uintptr(len(dst)) + if len(dst) == 0 { + return 0, nil + } + + fault, sig := memcpy(unsafe.Pointer(&dst[0]), src, toCopy) + if sig == 0 { + return len(dst), nil + } + + faultN, srcN := uintptr(fault), uintptr(src) + if faultN < srcN || faultN >= srcN+toCopy { + panic(fmt.Sprintf("CopyIn raised signal %d at %#x, which is outside source [%#x, %#x)", sig, faultN, srcN, srcN+toCopy)) + } + + // memcpy might have ended the copy up to maxRegisterSize bytes before + // fault, if an instruction caused a memory access that straddled two + // pages, and the second one faulted. Try to copy up to the fault. + var done int + if faultN-srcN > maxRegisterSize { + done = int(faultN - srcN - maxRegisterSize) + } + n, err := CopyIn(dst[done:int(faultN-srcN)], unsafe.Pointer(srcN+uintptr(done))) + done += n + if err != nil { + return done, err + } + return done, errorFromFaultSignal(fault, sig) +} + +// CopyOut copies len(src) bytes from src to dst. If returns the number of +// bytes done and an error if SIGSEGV or SIGBUS is received while writing to +// dst. +func CopyOut(dst unsafe.Pointer, src []byte) (int, error) { + toCopy := uintptr(len(src)) + if toCopy == 0 { + return 0, nil + } + + fault, sig := memcpy(dst, unsafe.Pointer(&src[0]), toCopy) + if sig == 0 { + return len(src), nil + } + + faultN, dstN := uintptr(fault), uintptr(dst) + if faultN < dstN || faultN >= dstN+toCopy { + panic(fmt.Sprintf("CopyOut raised signal %d at %#x, which is outside destination [%#x, %#x)", sig, faultN, dstN, dstN+toCopy)) + } + + // memcpy might have ended the copy up to maxRegisterSize bytes before + // fault, if an instruction caused a memory access that straddled two + // pages, and the second one faulted. Try to copy up to the fault. + var done int + if faultN-dstN > maxRegisterSize { + done = int(faultN - dstN - maxRegisterSize) + } + n, err := CopyOut(unsafe.Pointer(dstN+uintptr(done)), src[done:int(faultN-dstN)]) + done += n + if err != nil { + return done, err + } + return done, errorFromFaultSignal(fault, sig) +} + +// Copy copies toCopy bytes from src to dst. It returns the number of bytes +// copied and an error if SIGSEGV or SIGBUS is received while reading from src +// or writing to dst. +// +// Data is copied in order; if [src, src+toCopy) and [dst, dst+toCopy) overlap, +// the resulting contents of dst are unspecified. +func Copy(dst, src unsafe.Pointer, toCopy uintptr) (uintptr, error) { + if toCopy == 0 { + return 0, nil + } + + fault, sig := memcpy(dst, src, toCopy) + if sig == 0 { + return toCopy, nil + } + + // Did the fault occur while reading from src or writing to dst? + faultN, srcN, dstN := uintptr(fault), uintptr(src), uintptr(dst) + faultAfterSrc := ^uintptr(0) + if faultN >= srcN { + faultAfterSrc = faultN - srcN + } + faultAfterDst := ^uintptr(0) + if faultN >= dstN { + faultAfterDst = faultN - dstN + } + if faultAfterSrc >= toCopy && faultAfterDst >= toCopy { + panic(fmt.Sprintf("Copy raised signal %d at %#x, which is outside source [%#x, %#x) and destination [%#x, %#x)", sig, faultN, srcN, srcN+toCopy, dstN, dstN+toCopy)) + } + faultedAfter := faultAfterSrc + if faultedAfter > faultAfterDst { + faultedAfter = faultAfterDst + } + + // memcpy might have ended the copy up to maxRegisterSize bytes before + // fault, if an instruction caused a memory access that straddled two + // pages, and the second one faulted. Try to copy up to the fault. + var done uintptr + if faultedAfter > maxRegisterSize { + done = faultedAfter - maxRegisterSize + } + n, err := Copy(unsafe.Pointer(dstN+done), unsafe.Pointer(srcN+done), faultedAfter-done) + done += n + if err != nil { + return done, err + } + return done, errorFromFaultSignal(fault, sig) +} + +// ZeroOut writes toZero zero bytes to dst. It returns the number of bytes +// written and an error if SIGSEGV or SIGBUS is received while writing to dst. +func ZeroOut(dst unsafe.Pointer, toZero uintptr) (uintptr, error) { + if toZero == 0 { + return 0, nil + } + + fault, sig := memclr(dst, toZero) + if sig == 0 { + return toZero, nil + } + + faultN, dstN := uintptr(fault), uintptr(dst) + if faultN < dstN || faultN >= dstN+toZero { + panic(fmt.Sprintf("ZeroOut raised signal %d at %#x, which is outside destination [%#x, %#x)", sig, faultN, dstN, dstN+toZero)) + } + + // memclr might have ended the write up to maxRegisterSize bytes before + // fault, if an instruction caused a memory access that straddled two + // pages, and the second one faulted. Try to write up to the fault. + var done uintptr + if faultN-dstN > maxRegisterSize { + done = faultN - dstN - maxRegisterSize + } + n, err := ZeroOut(unsafe.Pointer(dstN+done), faultN-dstN-done) + done += n + if err != nil { + return done, err + } + return done, errorFromFaultSignal(fault, sig) +} + +// SwapUint32 is equivalent to sync/atomic.SwapUint32, except that it returns +// an error if SIGSEGV or SIGBUS is received while accessing ptr, or if ptr is +// not aligned to a 4-byte boundary. +func SwapUint32(ptr unsafe.Pointer, new uint32) (uint32, error) { + if addr := uintptr(ptr); addr&3 != 0 { + return 0, AlignmentError{addr, 4} + } + old, sig := swapUint32(ptr, new) + return old, errorFromFaultSignal(ptr, sig) +} + +// SwapUint64 is equivalent to sync/atomic.SwapUint64, except that it returns +// an error if SIGSEGV or SIGBUS is received while accessing ptr, or if ptr is +// not aligned to an 8-byte boundary. +func SwapUint64(ptr unsafe.Pointer, new uint64) (uint64, error) { + if addr := uintptr(ptr); addr&7 != 0 { + return 0, AlignmentError{addr, 8} + } + old, sig := swapUint64(ptr, new) + return old, errorFromFaultSignal(ptr, sig) +} + +// CompareAndSwapUint32 is equivalent to atomicbitops.CompareAndSwapUint32, +// except that it returns an error if SIGSEGV or SIGBUS is received while +// accessing ptr, or if ptr is not aligned to a 4-byte boundary. +func CompareAndSwapUint32(ptr unsafe.Pointer, old, new uint32) (uint32, error) { + if addr := uintptr(ptr); addr&3 != 0 { + return 0, AlignmentError{addr, 4} + } + prev, sig := compareAndSwapUint32(ptr, old, new) + return prev, errorFromFaultSignal(ptr, sig) +} + +// LoadUint32 is like sync/atomic.LoadUint32, but operates with user memory. It +// may fail with SIGSEGV or SIGBUS if it is received while reading from ptr. +// +// Preconditions: ptr must be aligned to a 4-byte boundary. +func LoadUint32(ptr unsafe.Pointer) (uint32, error) { + if addr := uintptr(ptr); addr&3 != 0 { + return 0, AlignmentError{addr, 4} + } + val, sig := loadUint32(ptr) + return val, errorFromFaultSignal(ptr, sig) +} + +func errorFromFaultSignal(addr unsafe.Pointer, sig int32) error { + switch sig { + case 0: + return nil + case int32(syscall.SIGSEGV): + return SegvError{uintptr(addr)} + case int32(syscall.SIGBUS): + return BusError{uintptr(addr)} + default: + panic(fmt.Sprintf("safecopy got unexpected signal %d at address %#x", sig, addr)) + } +} + +// ReplaceSignalHandler replaces the existing signal handler for the provided +// signal with the one that handles faults in safecopy-protected functions. +// +// It stores the value of the previously set handler in previous. +// +// This function will be called on initialization in order to install safecopy +// handlers for appropriate signals. These handlers will call the previous +// handler however, and if this is function is being used externally then the +// same courtesy is expected. +func ReplaceSignalHandler(sig syscall.Signal, handler uintptr, previous *uintptr) error { + var sa struct { + handler uintptr + flags uint64 + restorer uintptr + mask uint64 + } + const maskLen = 8 + + // Get the existing signal handler information, and save the current + // handler. Once we replace it, we will use this pointer to fall back to + // it when we receive other signals. + if _, _, e := syscall.RawSyscall6(syscall.SYS_RT_SIGACTION, uintptr(sig), 0, uintptr(unsafe.Pointer(&sa)), maskLen, 0, 0); e != 0 { + return e + } + + // Fail if there isn't a previous handler. + if sa.handler == 0 { + return fmt.Errorf("previous handler for signal %x isn't set", sig) + } + + *previous = sa.handler + + // Install our own handler. + sa.handler = handler + if _, _, e := syscall.RawSyscall6(syscall.SYS_RT_SIGACTION, uintptr(sig), uintptr(unsafe.Pointer(&sa)), 0, maskLen, 0, 0); e != 0 { + return e + } + + return nil +} diff --git a/pkg/safecopy/sighandler_amd64.s b/pkg/safecopy/sighandler_amd64.s new file mode 100644 index 000000000..475ae48e9 --- /dev/null +++ b/pkg/safecopy/sighandler_amd64.s @@ -0,0 +1,133 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +#include "textflag.h" + +// The signals handled by sigHandler. +#define SIGBUS 7 +#define SIGSEGV 11 + +// Offsets to the registers in context->uc_mcontext.gregs[]. +#define REG_RDI 0x68 +#define REG_RAX 0x90 +#define REG_IP 0xa8 + +// Offset to the si_addr field of siginfo. +#define SI_CODE 0x08 +#define SI_ADDR 0x10 + +// signalHandler is the signal handler for SIGSEGV and SIGBUS signals. It must +// not be set up as a handler to any other signals. +// +// If the instruction causing the signal is within a safecopy-protected +// function, the signal is handled such that execution resumes in the +// appropriate fault handling stub with AX containing the faulting address and +// DI containing the signal number. Otherwise control is transferred to the +// previously configured signal handler (savedSigSegvHandler or +// savedSigBusHandler). +// +// This function cannot be written in go because it runs whenever a signal is +// received by the thread (preempting whatever was running), which includes when +// garbage collector has stopped or isn't expecting any interactions (like +// barriers). +// +// The arguments are the following: +// DI - The signal number. +// SI - Pointer to siginfo_t structure. +// DX - Pointer to ucontext structure. +TEXT ·signalHandler(SB),NOSPLIT,$0 + // Check if the signal is from the kernel. + MOVQ $0x0, CX + CMPL CX, SI_CODE(SI) + JGE original_handler + + // Check if RIP is within the area we care about. + MOVQ REG_IP(DX), CX + CMPQ CX, ·memcpyBegin(SB) + JB not_memcpy + CMPQ CX, ·memcpyEnd(SB) + JAE not_memcpy + + // Modify the context such that execution will resume in the fault + // handler. + LEAQ handleMemcpyFault(SB), CX + JMP handle_fault + +not_memcpy: + CMPQ CX, ·memclrBegin(SB) + JB not_memclr + CMPQ CX, ·memclrEnd(SB) + JAE not_memclr + + LEAQ handleMemclrFault(SB), CX + JMP handle_fault + +not_memclr: + CMPQ CX, ·swapUint32Begin(SB) + JB not_swapuint32 + CMPQ CX, ·swapUint32End(SB) + JAE not_swapuint32 + + LEAQ handleSwapUint32Fault(SB), CX + JMP handle_fault + +not_swapuint32: + CMPQ CX, ·swapUint64Begin(SB) + JB not_swapuint64 + CMPQ CX, ·swapUint64End(SB) + JAE not_swapuint64 + + LEAQ handleSwapUint64Fault(SB), CX + JMP handle_fault + +not_swapuint64: + CMPQ CX, ·compareAndSwapUint32Begin(SB) + JB not_casuint32 + CMPQ CX, ·compareAndSwapUint32End(SB) + JAE not_casuint32 + + LEAQ handleCompareAndSwapUint32Fault(SB), CX + JMP handle_fault + +not_casuint32: + CMPQ CX, ·loadUint32Begin(SB) + JB not_loaduint32 + CMPQ CX, ·loadUint32End(SB) + JAE not_loaduint32 + + LEAQ handleLoadUint32Fault(SB), CX + JMP handle_fault + +not_loaduint32: +original_handler: + // Jump to the previous signal handler, which is likely the golang one. + XORQ CX, CX + MOVQ ·savedSigBusHandler(SB), AX + CMPL DI, $SIGSEGV + CMOVQEQ ·savedSigSegVHandler(SB), AX + JMP AX + +handle_fault: + // Entered with the address of the fault handler in RCX; store it in + // RIP. + MOVQ CX, REG_IP(DX) + + // Store the faulting address in RAX. + MOVQ SI_ADDR(SI), CX + MOVQ CX, REG_RAX(DX) + + // Store the signal number in EDI. + MOVL DI, REG_RDI(DX) + + RET diff --git a/pkg/safecopy/sighandler_arm64.s b/pkg/safecopy/sighandler_arm64.s new file mode 100644 index 000000000..53e4ac2c1 --- /dev/null +++ b/pkg/safecopy/sighandler_arm64.s @@ -0,0 +1,143 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +#include "textflag.h" + +// The signals handled by sigHandler. +#define SIGBUS 7 +#define SIGSEGV 11 + +// Offsets to the registers in context->uc_mcontext.gregs[]. +#define REG_R0 0xB8 +#define REG_R1 0xC0 +#define REG_PC 0x1B8 + +// Offset to the si_addr field of siginfo. +#define SI_CODE 0x08 +#define SI_ADDR 0x10 + +// signalHandler is the signal handler for SIGSEGV and SIGBUS signals. It must +// not be set up as a handler to any other signals. +// +// If the instruction causing the signal is within a safecopy-protected +// function, the signal is handled such that execution resumes in the +// appropriate fault handling stub with R0 containing the faulting address and +// R1 containing the signal number. Otherwise control is transferred to the +// previously configured signal handler (savedSigSegvHandler or +// savedSigBusHandler). +// +// This function cannot be written in go because it runs whenever a signal is +// received by the thread (preempting whatever was running), which includes when +// garbage collector has stopped or isn't expecting any interactions (like +// barriers). +// +// The arguments are the following: +// R0 - The signal number. +// R1 - Pointer to siginfo_t structure. +// R2 - Pointer to ucontext structure. +TEXT ·signalHandler(SB),NOSPLIT,$0 + // Check if the signal is from the kernel, si_code > 0 means a kernel signal. + MOVD SI_CODE(R1), R7 + CMPW $0x0, R7 + BLE original_handler + + // Check if PC is within the area we care about. + MOVD REG_PC(R2), R7 + MOVD ·memcpyBegin(SB), R8 + CMP R8, R7 + BLO not_memcpy + MOVD ·memcpyEnd(SB), R8 + CMP R8, R7 + BHS not_memcpy + + // Modify the context such that execution will resume in the fault handler. + MOVD $handleMemcpyFault(SB), R7 + B handle_fault + +not_memcpy: + MOVD ·memclrBegin(SB), R8 + CMP R8, R7 + BLO not_memclr + MOVD ·memclrEnd(SB), R8 + CMP R8, R7 + BHS not_memclr + + MOVD $handleMemclrFault(SB), R7 + B handle_fault + +not_memclr: + MOVD ·swapUint32Begin(SB), R8 + CMP R8, R7 + BLO not_swapuint32 + MOVD ·swapUint32End(SB), R8 + CMP R8, R7 + BHS not_swapuint32 + + MOVD $handleSwapUint32Fault(SB), R7 + B handle_fault + +not_swapuint32: + MOVD ·swapUint64Begin(SB), R8 + CMP R8, R7 + BLO not_swapuint64 + MOVD ·swapUint64End(SB), R8 + CMP R8, R7 + BHS not_swapuint64 + + MOVD $handleSwapUint64Fault(SB), R7 + B handle_fault + +not_swapuint64: + MOVD ·compareAndSwapUint32Begin(SB), R8 + CMP R8, R7 + BLO not_casuint32 + MOVD ·compareAndSwapUint32End(SB), R8 + CMP R8, R7 + BHS not_casuint32 + + MOVD $handleCompareAndSwapUint32Fault(SB), R7 + B handle_fault + +not_casuint32: + MOVD ·loadUint32Begin(SB), R8 + CMP R8, R7 + BLO not_loaduint32 + MOVD ·loadUint32End(SB), R8 + CMP R8, R7 + BHS not_loaduint32 + + MOVD $handleLoadUint32Fault(SB), R7 + B handle_fault + +not_loaduint32: +original_handler: + // Jump to the previous signal handler, which is likely the golang one. + MOVD ·savedSigBusHandler(SB), R7 + MOVD ·savedSigSegVHandler(SB), R8 + CMPW $SIGSEGV, R0 + CSEL EQ, R8, R7, R7 + B (R7) + +handle_fault: + // Entered with the address of the fault handler in R7; store it in PC. + MOVD R7, REG_PC(R2) + + // Store the faulting address in R0. + MOVD SI_ADDR(R1), R7 + MOVD R7, REG_R0(R2) + + // Store the signal number in R1. + MOVW R0, REG_R1(R2) + + RET diff --git a/pkg/safemem/BUILD b/pkg/safemem/BUILD new file mode 100644 index 000000000..ce30382ab --- /dev/null +++ b/pkg/safemem/BUILD @@ -0,0 +1,27 @@ +load("//tools:defs.bzl", "go_library", "go_test") + +package(licenses = ["notice"]) + +go_library( + name = "safemem", + srcs = [ + "block_unsafe.go", + "io.go", + "safemem.go", + "seq_unsafe.go", + ], + visibility = ["//:sandbox"], + deps = [ + "//pkg/safecopy", + ], +) + +go_test( + name = "safemem_test", + size = "small", + srcs = [ + "io_test.go", + "seq_test.go", + ], + library = ":safemem", +) diff --git a/pkg/safemem/block_unsafe.go b/pkg/safemem/block_unsafe.go new file mode 100644 index 000000000..e7fd30743 --- /dev/null +++ b/pkg/safemem/block_unsafe.go @@ -0,0 +1,279 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package safemem + +import ( + "fmt" + "reflect" + "unsafe" + + "gvisor.dev/gvisor/pkg/safecopy" +) + +// A Block is a range of contiguous bytes, similar to []byte but with the +// following differences: +// +// - The memory represented by a Block may require the use of safecopy to +// access. +// +// - Block does not carry a capacity and cannot be expanded. +// +// Blocks are immutable and may be copied by value. The zero value of Block +// represents an empty range, analogous to a nil []byte. +type Block struct { + // [start, start+length) is the represented memory. + // + // start is an unsafe.Pointer to ensure that Block prevents the represented + // memory from being garbage-collected. + start unsafe.Pointer + length int + + // needSafecopy is true if accessing the represented memory requires the + // use of safecopy. + needSafecopy bool +} + +// BlockFromSafeSlice returns a Block equivalent to slice, which is safe to +// access without safecopy. +func BlockFromSafeSlice(slice []byte) Block { + return blockFromSlice(slice, false) +} + +// BlockFromUnsafeSlice returns a Block equivalent to bs, which is not safe to +// access without safecopy. +func BlockFromUnsafeSlice(slice []byte) Block { + return blockFromSlice(slice, true) +} + +func blockFromSlice(slice []byte, needSafecopy bool) Block { + if len(slice) == 0 { + return Block{} + } + return Block{ + start: unsafe.Pointer(&slice[0]), + length: len(slice), + needSafecopy: needSafecopy, + } +} + +// BlockFromSafePointer returns a Block equivalent to [ptr, ptr+len), which is +// safe to access without safecopy. +// +// Preconditions: ptr+len does not overflow. +func BlockFromSafePointer(ptr unsafe.Pointer, len int) Block { + return blockFromPointer(ptr, len, false) +} + +// BlockFromUnsafePointer returns a Block equivalent to [ptr, ptr+len), which +// is not safe to access without safecopy. +// +// Preconditions: ptr+len does not overflow. +func BlockFromUnsafePointer(ptr unsafe.Pointer, len int) Block { + return blockFromPointer(ptr, len, true) +} + +func blockFromPointer(ptr unsafe.Pointer, len int, needSafecopy bool) Block { + if uptr := uintptr(ptr); uptr+uintptr(len) < uptr { + panic(fmt.Sprintf("ptr %#x + len %#x overflows", ptr, len)) + } + return Block{ + start: ptr, + length: len, + needSafecopy: needSafecopy, + } +} + +// DropFirst returns a Block equivalent to b, but with the first n bytes +// omitted. It is analogous to the [n:] operation on a slice, except that if n +// > b.Len(), DropFirst returns an empty Block instead of panicking. +// +// Preconditions: n >= 0. +func (b Block) DropFirst(n int) Block { + if n < 0 { + panic(fmt.Sprintf("invalid n: %d", n)) + } + return b.DropFirst64(uint64(n)) +} + +// DropFirst64 is equivalent to DropFirst but takes a uint64. +func (b Block) DropFirst64(n uint64) Block { + if n >= uint64(b.length) { + return Block{} + } + return Block{ + start: unsafe.Pointer(uintptr(b.start) + uintptr(n)), + length: b.length - int(n), + needSafecopy: b.needSafecopy, + } +} + +// TakeFirst returns a Block equivalent to the first n bytes of b. It is +// analogous to the [:n] operation on a slice, except that if n > b.Len(), +// TakeFirst returns a copy of b instead of panicking. +// +// Preconditions: n >= 0. +func (b Block) TakeFirst(n int) Block { + if n < 0 { + panic(fmt.Sprintf("invalid n: %d", n)) + } + return b.TakeFirst64(uint64(n)) +} + +// TakeFirst64 is equivalent to TakeFirst but takes a uint64. +func (b Block) TakeFirst64(n uint64) Block { + if n == 0 { + return Block{} + } + if n >= uint64(b.length) { + return b + } + return Block{ + start: b.start, + length: int(n), + needSafecopy: b.needSafecopy, + } +} + +// ToSlice returns a []byte equivalent to b. +func (b Block) ToSlice() []byte { + var bs []byte + hdr := (*reflect.SliceHeader)(unsafe.Pointer(&bs)) + hdr.Data = uintptr(b.start) + hdr.Len = b.length + hdr.Cap = b.length + return bs +} + +// Addr returns b's start address as a uintptr. It returns uintptr instead of +// unsafe.Pointer so that code using safemem cannot obtain unsafe.Pointers +// without importing the unsafe package explicitly. +// +// Note that a uintptr is not recognized as a pointer by the garbage collector, +// such that if there are no uses of b after a call to b.Addr() and the address +// is to Go-managed memory, the returned uintptr does not prevent garbage +// collection of the pointee. +func (b Block) Addr() uintptr { + return uintptr(b.start) +} + +// Len returns b's length in bytes. +func (b Block) Len() int { + return b.length +} + +// NeedSafecopy returns true if accessing b.ToSlice() requires the use of safecopy. +func (b Block) NeedSafecopy() bool { + return b.needSafecopy +} + +// String implements fmt.Stringer.String. +func (b Block) String() string { + if uintptr(b.start) == 0 && b.length == 0 { + return "" + } + var suffix string + if b.needSafecopy { + suffix = "*" + } + return fmt.Sprintf("[%#x-%#x)%s", uintptr(b.start), uintptr(b.start)+uintptr(b.length), suffix) +} + +// Copy copies src.Len() or dst.Len() bytes, whichever is less, from src +// to dst and returns the number of bytes copied. +// +// If src and dst overlap, the data stored in dst is unspecified. +func Copy(dst, src Block) (int, error) { + if !dst.needSafecopy && !src.needSafecopy { + return copy(dst.ToSlice(), src.ToSlice()), nil + } + + n := dst.length + if n > src.length { + n = src.length + } + if n == 0 { + return 0, nil + } + + switch { + case dst.needSafecopy && !src.needSafecopy: + return safecopy.CopyOut(dst.start, src.TakeFirst(n).ToSlice()) + case !dst.needSafecopy && src.needSafecopy: + return safecopy.CopyIn(dst.TakeFirst(n).ToSlice(), src.start) + case dst.needSafecopy && src.needSafecopy: + n64, err := safecopy.Copy(dst.start, src.start, uintptr(n)) + return int(n64), err + default: + panic("unreachable") + } +} + +// Zero sets all bytes in dst to 0 and returns the number of bytes zeroed. +func Zero(dst Block) (int, error) { + if !dst.needSafecopy { + bs := dst.ToSlice() + for i := range bs { + bs[i] = 0 + } + return len(bs), nil + } + + n64, err := safecopy.ZeroOut(dst.start, uintptr(dst.length)) + return int(n64), err +} + +// Safecopy atomics are no slower than non-safecopy atomics, so use the former +// even when !b.needSafecopy to get consistent alignment checking. + +// SwapUint32 invokes safecopy.SwapUint32 on the first 4 bytes of b. +// +// Preconditions: b.Len() >= 4. +func SwapUint32(b Block, new uint32) (uint32, error) { + if b.length < 4 { + panic(fmt.Sprintf("insufficient length: %d", b.length)) + } + return safecopy.SwapUint32(b.start, new) +} + +// SwapUint64 invokes safecopy.SwapUint64 on the first 8 bytes of b. +// +// Preconditions: b.Len() >= 8. +func SwapUint64(b Block, new uint64) (uint64, error) { + if b.length < 8 { + panic(fmt.Sprintf("insufficient length: %d", b.length)) + } + return safecopy.SwapUint64(b.start, new) +} + +// CompareAndSwapUint32 invokes safecopy.CompareAndSwapUint32 on the first 4 +// bytes of b. +// +// Preconditions: b.Len() >= 4. +func CompareAndSwapUint32(b Block, old, new uint32) (uint32, error) { + if b.length < 4 { + panic(fmt.Sprintf("insufficient length: %d", b.length)) + } + return safecopy.CompareAndSwapUint32(b.start, old, new) +} + +// LoadUint32 invokes safecopy.LoadUint32 on the first 4 bytes of b. +// +// Preconditions: b.Len() >= 4. +func LoadUint32(b Block) (uint32, error) { + if b.length < 4 { + panic(fmt.Sprintf("insufficient length: %d", b.length)) + } + return safecopy.LoadUint32(b.start) +} diff --git a/pkg/safemem/io.go b/pkg/safemem/io.go new file mode 100644 index 000000000..f039a5c34 --- /dev/null +++ b/pkg/safemem/io.go @@ -0,0 +1,392 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package safemem + +import ( + "errors" + "io" + "math" +) + +// ErrEndOfBlockSeq is returned by BlockSeqWriter when attempting to write +// beyond the end of the BlockSeq. +var ErrEndOfBlockSeq = errors.New("write beyond end of BlockSeq") + +// Reader represents a streaming byte source like io.Reader. +type Reader interface { + // ReadToBlocks reads up to dsts.NumBytes() bytes into dsts and returns the + // number of bytes read. It may return a partial read without an error + // (i.e. (n, nil) where 0 < n < dsts.NumBytes()). It should not return a + // full read with an error (i.e. (dsts.NumBytes(), err) where err != nil); + // note that this differs from io.Reader.Read (in particular, io.EOF should + // not be returned if ReadToBlocks successfully reads dsts.NumBytes() + // bytes.) + ReadToBlocks(dsts BlockSeq) (uint64, error) +} + +// Writer represents a streaming byte sink like io.Writer. +type Writer interface { + // WriteFromBlocks writes up to srcs.NumBytes() bytes from srcs and returns + // the number of bytes written. It may return a partial write without an + // error (i.e. (n, nil) where 0 < n < srcs.NumBytes()). It should not + // return a full write with an error (i.e. srcs.NumBytes(), err) where err + // != nil). + WriteFromBlocks(srcs BlockSeq) (uint64, error) +} + +// ReadFullToBlocks repeatedly invokes r.ReadToBlocks until dsts.NumBytes() +// bytes have been read or ReadToBlocks returns an error. +func ReadFullToBlocks(r Reader, dsts BlockSeq) (uint64, error) { + var done uint64 + for !dsts.IsEmpty() { + n, err := r.ReadToBlocks(dsts) + done += n + if err != nil { + return done, err + } + dsts = dsts.DropFirst64(n) + } + return done, nil +} + +// WriteFullFromBlocks repeatedly invokes w.WriteFromBlocks until +// srcs.NumBytes() bytes have been written or WriteFromBlocks returns an error. +func WriteFullFromBlocks(w Writer, srcs BlockSeq) (uint64, error) { + var done uint64 + for !srcs.IsEmpty() { + n, err := w.WriteFromBlocks(srcs) + done += n + if err != nil { + return done, err + } + srcs = srcs.DropFirst64(n) + } + return done, nil +} + +// BlockSeqReader implements Reader by reading from a BlockSeq. +type BlockSeqReader struct { + Blocks BlockSeq +} + +// ReadToBlocks implements Reader.ReadToBlocks. +func (r *BlockSeqReader) ReadToBlocks(dsts BlockSeq) (uint64, error) { + n, err := CopySeq(dsts, r.Blocks) + r.Blocks = r.Blocks.DropFirst64(n) + if err != nil { + return n, err + } + if n < dsts.NumBytes() { + return n, io.EOF + } + return n, nil +} + +// BlockSeqWriter implements Writer by writing to a BlockSeq. +type BlockSeqWriter struct { + Blocks BlockSeq +} + +// WriteFromBlocks implements Writer.WriteFromBlocks. +func (w *BlockSeqWriter) WriteFromBlocks(srcs BlockSeq) (uint64, error) { + n, err := CopySeq(w.Blocks, srcs) + w.Blocks = w.Blocks.DropFirst64(n) + if err != nil { + return n, err + } + if n < srcs.NumBytes() { + return n, ErrEndOfBlockSeq + } + return n, nil +} + +// ReaderFunc implements Reader for a function with the semantics of +// Reader.ReadToBlocks. +type ReaderFunc func(dsts BlockSeq) (uint64, error) + +// ReadToBlocks implements Reader.ReadToBlocks. +func (f ReaderFunc) ReadToBlocks(dsts BlockSeq) (uint64, error) { + return f(dsts) +} + +// WriterFunc implements Writer for a function with the semantics of +// Writer.WriteFromBlocks. +type WriterFunc func(srcs BlockSeq) (uint64, error) + +// WriteFromBlocks implements Writer.WriteFromBlocks. +func (f WriterFunc) WriteFromBlocks(srcs BlockSeq) (uint64, error) { + return f(srcs) +} + +// ToIOReader implements io.Reader for a (safemem.)Reader. +// +// ToIOReader will return a successful partial read iff Reader.ReadToBlocks does +// so. +type ToIOReader struct { + Reader Reader +} + +// Read implements io.Reader.Read. +func (r ToIOReader) Read(dst []byte) (int, error) { + n, err := r.Reader.ReadToBlocks(BlockSeqOf(BlockFromSafeSlice(dst))) + return int(n), err +} + +// ToIOWriter implements io.Writer for a (safemem.)Writer. +type ToIOWriter struct { + Writer Writer +} + +// Write implements io.Writer.Write. +func (w ToIOWriter) Write(src []byte) (int, error) { + // io.Writer does not permit partial writes. + n, err := WriteFullFromBlocks(w.Writer, BlockSeqOf(BlockFromSafeSlice(src))) + return int(n), err +} + +// FromIOReader implements Reader for an io.Reader by repeatedly invoking +// io.Reader.Read until it returns an error or partial read. This is not +// thread-safe. +// +// FromIOReader will return a successful partial read iff Reader.Read does so. +type FromIOReader struct { + Reader io.Reader +} + +// ReadToBlocks implements Reader.ReadToBlocks. +func (r FromIOReader) ReadToBlocks(dsts BlockSeq) (uint64, error) { + var buf []byte + var done uint64 + for !dsts.IsEmpty() { + dst := dsts.Head() + var n int + var err error + n, buf, err = r.readToBlock(dst, buf) + done += uint64(n) + if n != dst.Len() { + return done, err + } + dsts = dsts.Tail() + if err != nil { + if dsts.IsEmpty() && err == io.EOF { + return done, nil + } + return done, err + } + } + return done, nil +} + +func (r FromIOReader) readToBlock(dst Block, buf []byte) (int, []byte, error) { + // io.Reader isn't safecopy-aware, so we have to buffer Blocks that require + // safecopy. + if !dst.NeedSafecopy() { + n, err := r.Reader.Read(dst.ToSlice()) + return n, buf, err + } + if len(buf) < dst.Len() { + buf = make([]byte, dst.Len()) + } + rn, rerr := r.Reader.Read(buf[:dst.Len()]) + wbn, wberr := Copy(dst, BlockFromSafeSlice(buf[:rn])) + if wberr != nil { + return wbn, buf, wberr + } + return wbn, buf, rerr +} + +// FromIOReaderAt implements Reader for an io.ReaderAt. Does not repeatedly +// invoke io.ReaderAt.ReadAt because ReadAt is more strict than Read. A partial +// read indicates an error. This is not thread-safe. +type FromIOReaderAt struct { + ReaderAt io.ReaderAt + Offset int64 +} + +// ReadToBlocks implements Reader.ReadToBlocks. +func (r FromIOReaderAt) ReadToBlocks(dsts BlockSeq) (uint64, error) { + var buf []byte + var done uint64 + for !dsts.IsEmpty() { + dst := dsts.Head() + var n int + var err error + n, buf, err = r.readToBlock(dst, buf) + done += uint64(n) + if n != dst.Len() { + return done, err + } + dsts = dsts.Tail() + if err != nil { + if dsts.IsEmpty() && err == io.EOF { + return done, nil + } + return done, err + } + } + return done, nil +} + +func (r FromIOReaderAt) readToBlock(dst Block, buf []byte) (int, []byte, error) { + // io.Reader isn't safecopy-aware, so we have to buffer Blocks that require + // safecopy. + if !dst.NeedSafecopy() { + n, err := r.ReaderAt.ReadAt(dst.ToSlice(), r.Offset) + r.Offset += int64(n) + return n, buf, err + } + if len(buf) < dst.Len() { + buf = make([]byte, dst.Len()) + } + rn, rerr := r.ReaderAt.ReadAt(buf[:dst.Len()], r.Offset) + r.Offset += int64(rn) + wbn, wberr := Copy(dst, BlockFromSafeSlice(buf[:rn])) + if wberr != nil { + return wbn, buf, wberr + } + return wbn, buf, rerr +} + +// FromIOWriter implements Writer for an io.Writer by repeatedly invoking +// io.Writer.Write until it returns an error or partial write. +// +// FromIOWriter will tolerate implementations of io.Writer.Write that return +// partial writes with a nil error in contravention of io.Writer's +// requirements, since Writer is permitted to do so. FromIOWriter will return a +// successful partial write iff Writer.Write does so. +type FromIOWriter struct { + Writer io.Writer +} + +// WriteFromBlocks implements Writer.WriteFromBlocks. +func (w FromIOWriter) WriteFromBlocks(srcs BlockSeq) (uint64, error) { + var buf []byte + var done uint64 + for !srcs.IsEmpty() { + src := srcs.Head() + var n int + var err error + n, buf, err = w.writeFromBlock(src, buf) + done += uint64(n) + if n != src.Len() || err != nil { + return done, err + } + srcs = srcs.Tail() + } + return done, nil +} + +func (w FromIOWriter) writeFromBlock(src Block, buf []byte) (int, []byte, error) { + // io.Writer isn't safecopy-aware, so we have to buffer Blocks that require + // safecopy. + if !src.NeedSafecopy() { + n, err := w.Writer.Write(src.ToSlice()) + return n, buf, err + } + if len(buf) < src.Len() { + buf = make([]byte, src.Len()) + } + bufn, buferr := Copy(BlockFromSafeSlice(buf[:src.Len()]), src) + wn, werr := w.Writer.Write(buf[:bufn]) + if werr != nil { + return wn, buf, werr + } + return wn, buf, buferr +} + +// FromVecReaderFunc implements Reader for a function that reads data into a +// [][]byte and returns the number of bytes read as an int64. +type FromVecReaderFunc struct { + ReadVec func(dsts [][]byte) (int64, error) +} + +// ReadToBlocks implements Reader.ReadToBlocks. +// +// ReadToBlocks calls r.ReadVec at most once. +func (r FromVecReaderFunc) ReadToBlocks(dsts BlockSeq) (uint64, error) { + if dsts.IsEmpty() { + return 0, nil + } + // Ensure that we don't pass a [][]byte with a total length > MaxInt64. + dsts = dsts.TakeFirst64(uint64(math.MaxInt64)) + dstSlices := make([][]byte, 0, dsts.NumBlocks()) + // Buffer Blocks that require safecopy. + for tmp := dsts; !tmp.IsEmpty(); tmp = tmp.Tail() { + dst := tmp.Head() + if dst.NeedSafecopy() { + dstSlices = append(dstSlices, make([]byte, dst.Len())) + } else { + dstSlices = append(dstSlices, dst.ToSlice()) + } + } + rn, rerr := r.ReadVec(dstSlices) + dsts = dsts.TakeFirst64(uint64(rn)) + var done uint64 + var i int + for !dsts.IsEmpty() { + dst := dsts.Head() + if dst.NeedSafecopy() { + n, err := Copy(dst, BlockFromSafeSlice(dstSlices[i])) + done += uint64(n) + if err != nil { + return done, err + } + } else { + done += uint64(dst.Len()) + } + dsts = dsts.Tail() + i++ + } + return done, rerr +} + +// FromVecWriterFunc implements Writer for a function that writes data from a +// [][]byte and returns the number of bytes written. +type FromVecWriterFunc struct { + WriteVec func(srcs [][]byte) (int64, error) +} + +// WriteFromBlocks implements Writer.WriteFromBlocks. +// +// WriteFromBlocks calls w.WriteVec at most once. +func (w FromVecWriterFunc) WriteFromBlocks(srcs BlockSeq) (uint64, error) { + if srcs.IsEmpty() { + return 0, nil + } + // Ensure that we don't pass a [][]byte with a total length > MaxInt64. + srcs = srcs.TakeFirst64(uint64(math.MaxInt64)) + srcSlices := make([][]byte, 0, srcs.NumBlocks()) + // Buffer Blocks that require safecopy. + var buferr error + for tmp := srcs; !tmp.IsEmpty(); tmp = tmp.Tail() { + src := tmp.Head() + if src.NeedSafecopy() { + slice := make([]byte, src.Len()) + n, err := Copy(BlockFromSafeSlice(slice), src) + srcSlices = append(srcSlices, slice[:n]) + if err != nil { + buferr = err + break + } + } else { + srcSlices = append(srcSlices, src.ToSlice()) + } + } + n, err := w.WriteVec(srcSlices) + if err != nil { + return uint64(n), err + } + return uint64(n), buferr +} diff --git a/pkg/safemem/io_test.go b/pkg/safemem/io_test.go new file mode 100644 index 000000000..629741bee --- /dev/null +++ b/pkg/safemem/io_test.go @@ -0,0 +1,199 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package safemem + +import ( + "bytes" + "io" + "testing" +) + +func makeBlocks(slices ...[]byte) []Block { + blocks := make([]Block, 0, len(slices)) + for _, s := range slices { + blocks = append(blocks, BlockFromSafeSlice(s)) + } + return blocks +} + +func TestFromIOReaderFullRead(t *testing.T) { + r := FromIOReader{bytes.NewBufferString("foobar")} + dsts := makeBlocks(make([]byte, 3), make([]byte, 3)) + n, err := r.ReadToBlocks(BlockSeqFromSlice(dsts)) + if wantN := uint64(6); n != wantN || err != nil { + t.Errorf("ReadToBlocks: got (%v, %v), wanted (%v, nil)", n, err, wantN) + } + for i, want := range [][]byte{[]byte("foo"), []byte("bar")} { + if got := dsts[i].ToSlice(); !bytes.Equal(got, want) { + t.Errorf("dsts[%d]: got %q, wanted %q", i, got, want) + } + } +} + +type eofHidingReader struct { + Reader io.Reader +} + +func (r eofHidingReader) Read(dst []byte) (int, error) { + n, err := r.Reader.Read(dst) + if err == io.EOF { + return n, nil + } + return n, err +} + +func TestFromIOReaderPartialRead(t *testing.T) { + r := FromIOReader{eofHidingReader{bytes.NewBufferString("foob")}} + dsts := makeBlocks(make([]byte, 3), make([]byte, 3)) + n, err := r.ReadToBlocks(BlockSeqFromSlice(dsts)) + // FromIOReader should stop after the eofHidingReader returns (1, nil) + // for a 3-byte read. + if wantN := uint64(4); n != wantN || err != nil { + t.Errorf("ReadToBlocks: got (%v, %v), wanted (%v, nil)", n, err, wantN) + } + for i, want := range [][]byte{[]byte("foo"), []byte("b\x00\x00")} { + if got := dsts[i].ToSlice(); !bytes.Equal(got, want) { + t.Errorf("dsts[%d]: got %q, wanted %q", i, got, want) + } + } +} + +type singleByteReader struct { + Reader io.Reader +} + +func (r singleByteReader) Read(dst []byte) (int, error) { + if len(dst) == 0 { + return r.Reader.Read(dst) + } + return r.Reader.Read(dst[:1]) +} + +func TestSingleByteReader(t *testing.T) { + r := FromIOReader{singleByteReader{bytes.NewBufferString("foobar")}} + dsts := makeBlocks(make([]byte, 3), make([]byte, 3)) + n, err := r.ReadToBlocks(BlockSeqFromSlice(dsts)) + // FromIOReader should stop after the singleByteReader returns (1, nil) + // for a 3-byte read. + if wantN := uint64(1); n != wantN || err != nil { + t.Errorf("ReadToBlocks: got (%v, %v), wanted (%v, nil)", n, err, wantN) + } + for i, want := range [][]byte{[]byte("f\x00\x00"), []byte("\x00\x00\x00")} { + if got := dsts[i].ToSlice(); !bytes.Equal(got, want) { + t.Errorf("dsts[%d]: got %q, wanted %q", i, got, want) + } + } +} + +func TestReadFullToBlocks(t *testing.T) { + r := FromIOReader{singleByteReader{bytes.NewBufferString("foobar")}} + dsts := makeBlocks(make([]byte, 3), make([]byte, 3)) + n, err := ReadFullToBlocks(r, BlockSeqFromSlice(dsts)) + // ReadFullToBlocks should call into FromIOReader => singleByteReader + // repeatedly until dsts is exhausted. + if wantN := uint64(6); n != wantN || err != nil { + t.Errorf("ReadFullToBlocks: got (%v, %v), wanted (%v, nil)", n, err, wantN) + } + for i, want := range [][]byte{[]byte("foo"), []byte("bar")} { + if got := dsts[i].ToSlice(); !bytes.Equal(got, want) { + t.Errorf("dsts[%d]: got %q, wanted %q", i, got, want) + } + } +} + +func TestFromIOWriterFullWrite(t *testing.T) { + srcs := makeBlocks([]byte("foo"), []byte("bar")) + var dst bytes.Buffer + w := FromIOWriter{&dst} + n, err := w.WriteFromBlocks(BlockSeqFromSlice(srcs)) + if wantN := uint64(6); n != wantN || err != nil { + t.Errorf("WriteFromBlocks: got (%v, %v), wanted (%v, nil)", n, err, wantN) + } + if got, want := dst.Bytes(), []byte("foobar"); !bytes.Equal(got, want) { + t.Errorf("dst: got %q, wanted %q", got, want) + } +} + +type limitedWriter struct { + Writer io.Writer + Done int + Limit int +} + +func (w *limitedWriter) Write(src []byte) (int, error) { + count := len(src) + if count > (w.Limit - w.Done) { + count = w.Limit - w.Done + } + n, err := w.Writer.Write(src[:count]) + w.Done += n + return n, err +} + +func TestFromIOWriterPartialWrite(t *testing.T) { + srcs := makeBlocks([]byte("foo"), []byte("bar")) + var dst bytes.Buffer + w := FromIOWriter{&limitedWriter{&dst, 0, 4}} + n, err := w.WriteFromBlocks(BlockSeqFromSlice(srcs)) + // FromIOWriter should stop after the limitedWriter returns (1, nil) for a + // 3-byte write. + if wantN := uint64(4); n != wantN || err != nil { + t.Errorf("WriteFromBlocks: got (%v, %v), wanted (%v, nil)", n, err, wantN) + } + if got, want := dst.Bytes(), []byte("foob"); !bytes.Equal(got, want) { + t.Errorf("dst: got %q, wanted %q", got, want) + } +} + +type singleByteWriter struct { + Writer io.Writer +} + +func (w singleByteWriter) Write(src []byte) (int, error) { + if len(src) == 0 { + return w.Writer.Write(src) + } + return w.Writer.Write(src[:1]) +} + +func TestSingleByteWriter(t *testing.T) { + srcs := makeBlocks([]byte("foo"), []byte("bar")) + var dst bytes.Buffer + w := FromIOWriter{singleByteWriter{&dst}} + n, err := w.WriteFromBlocks(BlockSeqFromSlice(srcs)) + // FromIOWriter should stop after the singleByteWriter returns (1, nil) + // for a 3-byte write. + if wantN := uint64(1); n != wantN || err != nil { + t.Errorf("WriteFromBlocks: got (%v, %v), wanted (%v, nil)", n, err, wantN) + } + if got, want := dst.Bytes(), []byte("f"); !bytes.Equal(got, want) { + t.Errorf("dst: got %q, wanted %q", got, want) + } +} + +func TestWriteFullToBlocks(t *testing.T) { + srcs := makeBlocks([]byte("foo"), []byte("bar")) + var dst bytes.Buffer + w := FromIOWriter{singleByteWriter{&dst}} + n, err := WriteFullFromBlocks(w, BlockSeqFromSlice(srcs)) + // WriteFullToBlocks should call into FromIOWriter => singleByteWriter + // repeatedly until srcs is exhausted. + if wantN := uint64(6); n != wantN || err != nil { + t.Errorf("WriteFullFromBlocks: got (%v, %v), wanted (%v, nil)", n, err, wantN) + } + if got, want := dst.Bytes(), []byte("foobar"); !bytes.Equal(got, want) { + t.Errorf("dst: got %q, wanted %q", got, want) + } +} diff --git a/pkg/safemem/safemem.go b/pkg/safemem/safemem.go new file mode 100644 index 000000000..3e70d33a2 --- /dev/null +++ b/pkg/safemem/safemem.go @@ -0,0 +1,16 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// Package safemem provides the Block and BlockSeq types. +package safemem diff --git a/pkg/safemem/seq_test.go b/pkg/safemem/seq_test.go new file mode 100644 index 000000000..eba4bb535 --- /dev/null +++ b/pkg/safemem/seq_test.go @@ -0,0 +1,196 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package safemem + +import ( + "bytes" + "reflect" + "testing" +) + +type blockSeqTest struct { + desc string + + pieces []string + haveOffset bool + offset uint64 + haveLimit bool + limit uint64 + + want string +} + +func (t blockSeqTest) NonEmptyByteSlices() [][]byte { + // t is a value, so we can mutate it freely. + slices := make([][]byte, 0, len(t.pieces)) + for _, str := range t.pieces { + if t.haveOffset { + strOff := t.offset + if strOff > uint64(len(str)) { + strOff = uint64(len(str)) + } + str = str[strOff:] + t.offset -= strOff + } + if t.haveLimit { + strLim := t.limit + if strLim > uint64(len(str)) { + strLim = uint64(len(str)) + } + str = str[:strLim] + t.limit -= strLim + } + if len(str) != 0 { + slices = append(slices, []byte(str)) + } + } + return slices +} + +func (t blockSeqTest) BlockSeq() BlockSeq { + blocks := make([]Block, 0, len(t.pieces)) + for _, str := range t.pieces { + blocks = append(blocks, BlockFromSafeSlice([]byte(str))) + } + bs := BlockSeqFromSlice(blocks) + if t.haveOffset { + bs = bs.DropFirst64(t.offset) + } + if t.haveLimit { + bs = bs.TakeFirst64(t.limit) + } + return bs +} + +var blockSeqTests = []blockSeqTest{ + { + desc: "Empty sequence", + }, + { + desc: "Sequence of length 1", + pieces: []string{"foobar"}, + want: "foobar", + }, + { + desc: "Sequence of length 2", + pieces: []string{"foo", "bar"}, + want: "foobar", + }, + { + desc: "Empty Blocks", + pieces: []string{"", "foo", "", "", "bar", ""}, + want: "foobar", + }, + { + desc: "Sequence with non-zero offset", + pieces: []string{"foo", "bar"}, + haveOffset: true, + offset: 2, + want: "obar", + }, + { + desc: "Sequence with non-maximal limit", + pieces: []string{"foo", "bar"}, + haveLimit: true, + limit: 5, + want: "fooba", + }, + { + desc: "Sequence with offset and limit", + pieces: []string{"foo", "bar"}, + haveOffset: true, + offset: 2, + haveLimit: true, + limit: 3, + want: "oba", + }, +} + +func TestBlockSeqNumBytes(t *testing.T) { + for _, test := range blockSeqTests { + t.Run(test.desc, func(t *testing.T) { + if got, want := test.BlockSeq().NumBytes(), uint64(len(test.want)); got != want { + t.Errorf("NumBytes: got %d, wanted %d", got, want) + } + }) + } +} + +func TestBlockSeqIterBlocks(t *testing.T) { + // Tests BlockSeq iteration using Head/Tail. + for _, test := range blockSeqTests { + t.Run(test.desc, func(t *testing.T) { + srcs := test.BlockSeq() + // "Note that a non-nil empty slice and a nil slice ... are not + // deeply equal." - reflect + slices := make([][]byte, 0, 0) + for !srcs.IsEmpty() { + src := srcs.Head() + slices = append(slices, src.ToSlice()) + nextSrcs := srcs.Tail() + if got, want := nextSrcs.NumBytes(), srcs.NumBytes()-uint64(src.Len()); got != want { + t.Fatalf("%v.Tail(): got %v (%d bytes), wanted %d bytes", srcs, nextSrcs, got, want) + } + srcs = nextSrcs + } + if wantSlices := test.NonEmptyByteSlices(); !reflect.DeepEqual(slices, wantSlices) { + t.Errorf("Accumulated slices: got %v, wanted %v", slices, wantSlices) + } + }) + } +} + +func TestBlockSeqIterBytes(t *testing.T) { + // Tests BlockSeq iteration using Head/DropFirst. + for _, test := range blockSeqTests { + t.Run(test.desc, func(t *testing.T) { + srcs := test.BlockSeq() + var dst bytes.Buffer + for !srcs.IsEmpty() { + src := srcs.Head() + var b [1]byte + n, err := Copy(BlockFromSafeSlice(b[:]), src) + if n != 1 || err != nil { + t.Fatalf("Copy: got (%v, %v), wanted (1, nil)", n, err) + } + dst.WriteByte(b[0]) + nextSrcs := srcs.DropFirst(1) + if got, want := nextSrcs.NumBytes(), srcs.NumBytes()-1; got != want { + t.Fatalf("%v.DropFirst(1): got %v (%d bytes), wanted %d bytes", srcs, nextSrcs, got, want) + } + srcs = nextSrcs + } + if got := string(dst.Bytes()); got != test.want { + t.Errorf("Copied string: got %q, wanted %q", got, test.want) + } + }) + } +} + +func TestBlockSeqDropBeyondLimit(t *testing.T) { + blocks := []Block{BlockFromSafeSlice([]byte("123")), BlockFromSafeSlice([]byte("4"))} + bs := BlockSeqFromSlice(blocks) + if got, want := bs.NumBytes(), uint64(4); got != want { + t.Errorf("%v.NumBytes(): got %d, wanted %d", bs, got, want) + } + bs = bs.TakeFirst(1) + if got, want := bs.NumBytes(), uint64(1); got != want { + t.Errorf("%v.NumBytes(): got %d, wanted %d", bs, got, want) + } + bs = bs.DropFirst(2) + if got, want := bs.NumBytes(), uint64(0); got != want { + t.Errorf("%v.NumBytes(): got %d, wanted %d", bs, got, want) + } +} diff --git a/pkg/safemem/seq_unsafe.go b/pkg/safemem/seq_unsafe.go new file mode 100644 index 000000000..354a95dde --- /dev/null +++ b/pkg/safemem/seq_unsafe.go @@ -0,0 +1,299 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package safemem + +import ( + "bytes" + "fmt" + "reflect" + "unsafe" +) + +// A BlockSeq represents a sequence of Blocks, each of which has non-zero +// length. +// +// BlockSeqs are immutable and may be copied by value. The zero value of +// BlockSeq represents an empty sequence. +type BlockSeq struct { + // If length is 0, then the BlockSeq is empty. Invariants: data == 0; + // offset == 0; limit == 0. + // + // If length is -1, then the BlockSeq represents the single Block{data, + // limit, false}. Invariants: offset == 0; limit > 0; limit does not + // overflow the range of an int. + // + // If length is -2, then the BlockSeq represents the single Block{data, + // limit, true}. Invariants: offset == 0; limit > 0; limit does not + // overflow the range of an int. + // + // Otherwise, length >= 2, and the BlockSeq represents the `length` Blocks + // in the array of Blocks starting at address `data`, starting at `offset` + // bytes into the first Block and limited to the following `limit` bytes. + // Invariants: data != 0; offset < len(data[0]); limit > 0; offset+limit <= + // the combined length of all Blocks in the array; the first Block in the + // array has non-zero length. + // + // length is never 1; sequences consisting of a single Block are always + // stored inline (with length < 0). + data unsafe.Pointer + length int + offset int + limit uint64 +} + +// BlockSeqOf returns a BlockSeq representing the single Block b. +func BlockSeqOf(b Block) BlockSeq { + bs := BlockSeq{ + data: b.start, + length: -1, + limit: uint64(b.length), + } + if b.needSafecopy { + bs.length = -2 + } + return bs +} + +// BlockSeqFromSlice returns a BlockSeq representing all Blocks in slice. +// If slice contains Blocks with zero length, BlockSeq will skip them during +// iteration. +// +// Whether the returned BlockSeq shares memory with slice is unspecified; +// clients should avoid mutating slices passed to BlockSeqFromSlice. +// +// Preconditions: The combined length of all Blocks in slice <= math.MaxUint64. +func BlockSeqFromSlice(slice []Block) BlockSeq { + slice = skipEmpty(slice) + var limit uint64 + for _, b := range slice { + sum := limit + uint64(b.Len()) + if sum < limit { + panic("BlockSeq length overflows uint64") + } + limit = sum + } + return blockSeqFromSliceLimited(slice, limit) +} + +// Preconditions: The combined length of all Blocks in slice <= limit. If +// len(slice) != 0, the first Block in slice has non-zero length, and limit > +// 0. +func blockSeqFromSliceLimited(slice []Block, limit uint64) BlockSeq { + switch len(slice) { + case 0: + return BlockSeq{} + case 1: + return BlockSeqOf(slice[0].TakeFirst64(limit)) + default: + return BlockSeq{ + data: unsafe.Pointer(&slice[0]), + length: len(slice), + limit: limit, + } + } +} + +func skipEmpty(slice []Block) []Block { + for i, b := range slice { + if b.Len() != 0 { + return slice[i:] + } + } + return nil +} + +// IsEmpty returns true if bs contains no Blocks. +// +// Invariants: bs.IsEmpty() == (bs.NumBlocks() == 0) == (bs.NumBytes() == 0). +// (Of these, prefer to use bs.IsEmpty().) +func (bs BlockSeq) IsEmpty() bool { + return bs.length == 0 +} + +// NumBlocks returns the number of Blocks in bs. +func (bs BlockSeq) NumBlocks() int { + // In general, we have to count: if bs represents a windowed slice then the + // slice may contain Blocks with zero length, and bs.length may be larger + // than the actual number of Blocks due to bs.limit. + var n int + for !bs.IsEmpty() { + n++ + bs = bs.Tail() + } + return n +} + +// NumBytes returns the sum of Block.Len() for all Blocks in bs. +func (bs BlockSeq) NumBytes() uint64 { + return bs.limit +} + +// Head returns the first Block in bs. +// +// Preconditions: !bs.IsEmpty(). +func (bs BlockSeq) Head() Block { + if bs.length == 0 { + panic("empty BlockSeq") + } + if bs.length < 0 { + return bs.internalBlock() + } + return (*Block)(bs.data).DropFirst(bs.offset).TakeFirst64(bs.limit) +} + +// Preconditions: bs.length < 0. +func (bs BlockSeq) internalBlock() Block { + return Block{ + start: bs.data, + length: int(bs.limit), + needSafecopy: bs.length == -2, + } +} + +// Tail returns a BlockSeq consisting of all Blocks in bs after the first. +// +// Preconditions: !bs.IsEmpty(). +func (bs BlockSeq) Tail() BlockSeq { + if bs.length == 0 { + panic("empty BlockSeq") + } + if bs.length < 0 { + return BlockSeq{} + } + head := (*Block)(bs.data).DropFirst(bs.offset) + headLen := uint64(head.Len()) + if headLen >= bs.limit { + // The head Block exhausts the limit, so the tail is empty. + return BlockSeq{} + } + var extSlice []Block + extSliceHdr := (*reflect.SliceHeader)(unsafe.Pointer(&extSlice)) + extSliceHdr.Data = uintptr(bs.data) + extSliceHdr.Len = bs.length + extSliceHdr.Cap = bs.length + tailSlice := skipEmpty(extSlice[1:]) + tailLimit := bs.limit - headLen + return blockSeqFromSliceLimited(tailSlice, tailLimit) +} + +// DropFirst returns a BlockSeq equivalent to bs, but with the first n bytes +// omitted. If n > bs.NumBytes(), DropFirst returns an empty BlockSeq. +// +// Preconditions: n >= 0. +func (bs BlockSeq) DropFirst(n int) BlockSeq { + if n < 0 { + panic(fmt.Sprintf("invalid n: %d", n)) + } + return bs.DropFirst64(uint64(n)) +} + +// DropFirst64 is equivalent to DropFirst but takes an uint64. +func (bs BlockSeq) DropFirst64(n uint64) BlockSeq { + if n >= bs.limit { + return BlockSeq{} + } + for { + // Calling bs.Head() here is surprisingly expensive, so inline getting + // the head's length. + var headLen uint64 + if bs.length < 0 { + headLen = bs.limit + } else { + headLen = uint64((*Block)(bs.data).Len() - bs.offset) + } + if n < headLen { + // Dropping ends partway through the head Block. + if bs.length < 0 { + return BlockSeqOf(bs.internalBlock().DropFirst64(n)) + } + bs.offset += int(n) + bs.limit -= n + return bs + } + n -= headLen + bs = bs.Tail() + } +} + +// TakeFirst returns a BlockSeq equivalent to the first n bytes of bs. If n > +// bs.NumBytes(), TakeFirst returns a BlockSeq equivalent to bs. +// +// Preconditions: n >= 0. +func (bs BlockSeq) TakeFirst(n int) BlockSeq { + if n < 0 { + panic(fmt.Sprintf("invalid n: %d", n)) + } + return bs.TakeFirst64(uint64(n)) +} + +// TakeFirst64 is equivalent to TakeFirst but takes a uint64. +func (bs BlockSeq) TakeFirst64(n uint64) BlockSeq { + if n == 0 { + return BlockSeq{} + } + if bs.limit > n { + bs.limit = n + } + return bs +} + +// String implements fmt.Stringer.String. +func (bs BlockSeq) String() string { + var buf bytes.Buffer + buf.WriteByte('[') + var sep string + for !bs.IsEmpty() { + buf.WriteString(sep) + sep = " " + buf.WriteString(bs.Head().String()) + bs = bs.Tail() + } + buf.WriteByte(']') + return buf.String() +} + +// CopySeq copies srcs.NumBytes() or dsts.NumBytes() bytes, whichever is less, +// from srcs to dsts and returns the number of bytes copied. +// +// If srcs and dsts overlap, the data stored in dsts is unspecified. +func CopySeq(dsts, srcs BlockSeq) (uint64, error) { + var done uint64 + for !dsts.IsEmpty() && !srcs.IsEmpty() { + dst := dsts.Head() + src := srcs.Head() + n, err := Copy(dst, src) + done += uint64(n) + if err != nil { + return done, err + } + dsts = dsts.DropFirst(n) + srcs = srcs.DropFirst(n) + } + return done, nil +} + +// ZeroSeq sets all bytes in dsts to 0 and returns the number of bytes zeroed. +func ZeroSeq(dsts BlockSeq) (uint64, error) { + var done uint64 + for !dsts.IsEmpty() { + n, err := Zero(dsts.Head()) + done += uint64(n) + if err != nil { + return done, err + } + dsts = dsts.DropFirst(n) + } + return done, nil +} diff --git a/pkg/sentry/arch/BUILD b/pkg/sentry/arch/BUILD index 51ca09b24..34c0a867d 100644 --- a/pkg/sentry/arch/BUILD +++ b/pkg/sentry/arch/BUILD @@ -30,13 +30,13 @@ go_library( ":registers_go_proto", "//pkg/abi/linux", "//pkg/binary", + "//pkg/context", "//pkg/cpuid", "//pkg/log", - "//pkg/sentry/context", "//pkg/sentry/limits", - "//pkg/sentry/usermem", "//pkg/sync", "//pkg/syserror", + "//pkg/usermem", ], ) diff --git a/pkg/sentry/arch/arch.go b/pkg/sentry/arch/arch.go index 81ec98a77..1d11cc472 100644 --- a/pkg/sentry/arch/arch.go +++ b/pkg/sentry/arch/arch.go @@ -24,7 +24,7 @@ import ( "gvisor.dev/gvisor/pkg/cpuid" "gvisor.dev/gvisor/pkg/log" "gvisor.dev/gvisor/pkg/sentry/limits" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // Arch describes an architecture. diff --git a/pkg/sentry/arch/arch_aarch64.go b/pkg/sentry/arch/arch_aarch64.go index ea4dedbdf..3b6987665 100644 --- a/pkg/sentry/arch/arch_aarch64.go +++ b/pkg/sentry/arch/arch_aarch64.go @@ -25,8 +25,8 @@ import ( "gvisor.dev/gvisor/pkg/cpuid" "gvisor.dev/gvisor/pkg/log" rpb "gvisor.dev/gvisor/pkg/sentry/arch/registers_go_proto" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) const ( diff --git a/pkg/sentry/arch/arch_amd64.go b/pkg/sentry/arch/arch_amd64.go index 2aa08b1a9..85d6acc0f 100644 --- a/pkg/sentry/arch/arch_amd64.go +++ b/pkg/sentry/arch/arch_amd64.go @@ -25,7 +25,7 @@ import ( "gvisor.dev/gvisor/pkg/binary" "gvisor.dev/gvisor/pkg/cpuid" "gvisor.dev/gvisor/pkg/sentry/limits" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // Host specifies the host architecture. diff --git a/pkg/sentry/arch/arch_arm64.go b/pkg/sentry/arch/arch_arm64.go index 0d5b7d317..94f1a808f 100644 --- a/pkg/sentry/arch/arch_arm64.go +++ b/pkg/sentry/arch/arch_arm64.go @@ -21,7 +21,7 @@ import ( "gvisor.dev/gvisor/pkg/cpuid" "gvisor.dev/gvisor/pkg/sentry/limits" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // Host specifies the host architecture. diff --git a/pkg/sentry/arch/arch_state_x86.go b/pkg/sentry/arch/arch_state_x86.go index 84f11b0d1..d388ee9cf 100644 --- a/pkg/sentry/arch/arch_state_x86.go +++ b/pkg/sentry/arch/arch_state_x86.go @@ -21,7 +21,7 @@ import ( "syscall" "gvisor.dev/gvisor/pkg/cpuid" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // ErrFloatingPoint indicates a failed restore due to unusable floating point diff --git a/pkg/sentry/arch/arch_x86.go b/pkg/sentry/arch/arch_x86.go index 9f41e566f..a18093155 100644 --- a/pkg/sentry/arch/arch_x86.go +++ b/pkg/sentry/arch/arch_x86.go @@ -25,9 +25,9 @@ import ( "gvisor.dev/gvisor/pkg/cpuid" "gvisor.dev/gvisor/pkg/log" rpb "gvisor.dev/gvisor/pkg/sentry/arch/registers_go_proto" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // System-related constants for x86. diff --git a/pkg/sentry/arch/auxv.go b/pkg/sentry/arch/auxv.go index 4546b2ef9..2b4c8f3fc 100644 --- a/pkg/sentry/arch/auxv.go +++ b/pkg/sentry/arch/auxv.go @@ -15,7 +15,7 @@ package arch import ( - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // An AuxEntry represents an entry in an ELF auxiliary vector. diff --git a/pkg/sentry/arch/signal.go b/pkg/sentry/arch/signal.go index 402e46025..8b03d0187 100644 --- a/pkg/sentry/arch/signal.go +++ b/pkg/sentry/arch/signal.go @@ -16,7 +16,7 @@ package arch import ( "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // SignalAct represents the action that should be taken when a signal is diff --git a/pkg/sentry/arch/signal_amd64.go b/pkg/sentry/arch/signal_amd64.go index 1e4f9c3c2..81b92bb43 100644 --- a/pkg/sentry/arch/signal_amd64.go +++ b/pkg/sentry/arch/signal_amd64.go @@ -23,7 +23,7 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/log" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // SignalContext64 is equivalent to struct sigcontext, the type passed as the diff --git a/pkg/sentry/arch/signal_arm64.go b/pkg/sentry/arch/signal_arm64.go index 7d0e98935..4f4cc46a8 100644 --- a/pkg/sentry/arch/signal_arm64.go +++ b/pkg/sentry/arch/signal_arm64.go @@ -19,7 +19,7 @@ import ( "syscall" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // SignalContext64 is equivalent to struct sigcontext, the type passed as the diff --git a/pkg/sentry/arch/signal_stack.go b/pkg/sentry/arch/signal_stack.go index d324da705..1a6056171 100644 --- a/pkg/sentry/arch/signal_stack.go +++ b/pkg/sentry/arch/signal_stack.go @@ -17,7 +17,7 @@ package arch import ( - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) const ( diff --git a/pkg/sentry/arch/stack.go b/pkg/sentry/arch/stack.go index 7472c3c61..09bceabc9 100644 --- a/pkg/sentry/arch/stack.go +++ b/pkg/sentry/arch/stack.go @@ -18,8 +18,8 @@ import ( "encoding/binary" "fmt" - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/usermem" ) // Stack is a simple wrapper around a usermem.IO and an address. diff --git a/pkg/sentry/context/BUILD b/pkg/sentry/context/BUILD deleted file mode 100644 index e13a9ce20..000000000 --- a/pkg/sentry/context/BUILD +++ /dev/null @@ -1,13 +0,0 @@ -load("//tools:defs.bzl", "go_library") - -package(licenses = ["notice"]) - -go_library( - name = "context", - srcs = ["context.go"], - visibility = ["//pkg/sentry:internal"], - deps = [ - "//pkg/amutex", - "//pkg/log", - ], -) diff --git a/pkg/sentry/context/context.go b/pkg/sentry/context/context.go deleted file mode 100644 index 23e009ef3..000000000 --- a/pkg/sentry/context/context.go +++ /dev/null @@ -1,141 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -// Package context defines an internal context type. -// -// The given Context conforms to the standard Go context, but mandates -// additional methods that are specific to the kernel internals. Note however, -// that the Context described by this package carries additional constraints -// regarding concurrent access and retaining beyond the scope of a call. -// -// See the Context type for complete details. -package context - -import ( - "context" - "time" - - "gvisor.dev/gvisor/pkg/amutex" - "gvisor.dev/gvisor/pkg/log" -) - -type contextID int - -// Globally accessible values from a context. These keys are defined in the -// context package to resolve dependency cycles by not requiring the caller to -// import packages usually required to get these information. -const ( - // CtxThreadGroupID is the current thread group ID when a context represents - // a task context. The value is represented as an int32. - CtxThreadGroupID contextID = iota -) - -// ThreadGroupIDFromContext returns the current thread group ID when ctx -// represents a task context. -func ThreadGroupIDFromContext(ctx Context) (tgid int32, ok bool) { - if tgid := ctx.Value(CtxThreadGroupID); tgid != nil { - return tgid.(int32), true - } - return 0, false -} - -// A Context represents a thread of execution (hereafter "goroutine" to reflect -// Go idiosyncrasy). It carries state associated with the goroutine across API -// boundaries. -// -// While Context exists for essentially the same reasons as Go's standard -// context.Context, the standard type represents the state of an operation -// rather than that of a goroutine. This is a critical distinction: -// -// - Unlike context.Context, which "may be passed to functions running in -// different goroutines", it is *not safe* to use the same Context in multiple -// concurrent goroutines. -// -// - It is *not safe* to retain a Context passed to a function beyond the scope -// of that function call. -// -// In both cases, values extracted from the Context should be used instead. -type Context interface { - log.Logger - amutex.Sleeper - context.Context - - // UninterruptibleSleepStart indicates the beginning of an uninterruptible - // sleep state (equivalent to Linux's TASK_UNINTERRUPTIBLE). If deactivate - // is true and the Context represents a Task, the Task's AddressSpace is - // deactivated. - UninterruptibleSleepStart(deactivate bool) - - // UninterruptibleSleepFinish indicates the end of an uninterruptible sleep - // state that was begun by a previous call to UninterruptibleSleepStart. If - // activate is true and the Context represents a Task, the Task's - // AddressSpace is activated. Normally activate is the same value as the - // deactivate parameter passed to UninterruptibleSleepStart. - UninterruptibleSleepFinish(activate bool) -} - -// NoopSleeper is a noop implementation of amutex.Sleeper and UninterruptibleSleep -// methods for anonymous embedding in other types that do not implement sleeps. -type NoopSleeper struct { - amutex.NoopSleeper -} - -// UninterruptibleSleepStart does nothing. -func (NoopSleeper) UninterruptibleSleepStart(bool) {} - -// UninterruptibleSleepFinish does nothing. -func (NoopSleeper) UninterruptibleSleepFinish(bool) {} - -// Deadline returns zero values, meaning no deadline. -func (NoopSleeper) Deadline() (time.Time, bool) { - return time.Time{}, false -} - -// Done returns nil. -func (NoopSleeper) Done() <-chan struct{} { - return nil -} - -// Err returns nil. -func (NoopSleeper) Err() error { - return nil -} - -// logContext implements basic logging. -type logContext struct { - log.Logger - NoopSleeper -} - -// Value implements Context.Value. -func (logContext) Value(key interface{}) interface{} { - return nil -} - -// bgContext is the context returned by context.Background. -var bgContext = &logContext{Logger: log.Log()} - -// Background returns an empty context using the default logger. -// -// Users should be wary of using a Background context. Please tag any use with -// FIXME(b/38173783) and a note to remove this use. -// -// Generally, one should use the Task as their context when available, or avoid -// having to use a context in places where a Task is unavailable. -// -// Using a Background context for tests is fine, as long as no values are -// needed from the context in the tested code paths. -func Background() Context { - return bgContext -} diff --git a/pkg/sentry/context/contexttest/BUILD b/pkg/sentry/context/contexttest/BUILD deleted file mode 100644 index f91a6d4ed..000000000 --- a/pkg/sentry/context/contexttest/BUILD +++ /dev/null @@ -1,21 +0,0 @@ -load("//tools:defs.bzl", "go_library") - -package(licenses = ["notice"]) - -go_library( - name = "contexttest", - testonly = 1, - srcs = ["contexttest.go"], - visibility = ["//pkg/sentry:internal"], - deps = [ - "//pkg/memutil", - "//pkg/sentry/context", - "//pkg/sentry/kernel/auth", - "//pkg/sentry/kernel/time", - "//pkg/sentry/limits", - "//pkg/sentry/pgalloc", - "//pkg/sentry/platform", - "//pkg/sentry/platform/ptrace", - "//pkg/sentry/uniqueid", - ], -) diff --git a/pkg/sentry/context/contexttest/contexttest.go b/pkg/sentry/context/contexttest/contexttest.go deleted file mode 100644 index 15cf086a9..000000000 --- a/pkg/sentry/context/contexttest/contexttest.go +++ /dev/null @@ -1,188 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -// Package contexttest builds a test context.Context. -package contexttest - -import ( - "os" - "sync/atomic" - "testing" - "time" - - "gvisor.dev/gvisor/pkg/memutil" - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/kernel/auth" - ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" - "gvisor.dev/gvisor/pkg/sentry/limits" - "gvisor.dev/gvisor/pkg/sentry/pgalloc" - "gvisor.dev/gvisor/pkg/sentry/platform" - "gvisor.dev/gvisor/pkg/sentry/platform/ptrace" - "gvisor.dev/gvisor/pkg/sentry/uniqueid" -) - -// Context returns a Context that may be used in tests. Uses ptrace as the -// platform.Platform. -// -// Note that some filesystems may require a minimal kernel for testing, which -// this test context does not provide. For such tests, see kernel/contexttest. -func Context(tb testing.TB) context.Context { - const memfileName = "contexttest-memory" - memfd, err := memutil.CreateMemFD(memfileName, 0) - if err != nil { - tb.Fatalf("error creating application memory file: %v", err) - } - memfile := os.NewFile(uintptr(memfd), memfileName) - mf, err := pgalloc.NewMemoryFile(memfile, pgalloc.MemoryFileOpts{}) - if err != nil { - memfile.Close() - tb.Fatalf("error creating pgalloc.MemoryFile: %v", err) - } - p, err := ptrace.New() - if err != nil { - tb.Fatal(err) - } - // Test usage of context.Background is fine. - return &TestContext{ - Context: context.Background(), - l: limits.NewLimitSet(), - mf: mf, - platform: p, - creds: auth.NewAnonymousCredentials(), - otherValues: make(map[interface{}]interface{}), - } -} - -// TestContext represents a context with minimal functionality suitable for -// running tests. -type TestContext struct { - context.Context - l *limits.LimitSet - mf *pgalloc.MemoryFile - platform platform.Platform - creds *auth.Credentials - otherValues map[interface{}]interface{} -} - -// globalUniqueID tracks incremental unique identifiers for tests. -var globalUniqueID uint64 - -// globalUniqueIDProvider implements unix.UniqueIDProvider. -type globalUniqueIDProvider struct{} - -// UniqueID implements unix.UniqueIDProvider.UniqueID. -func (*globalUniqueIDProvider) UniqueID() uint64 { - return atomic.AddUint64(&globalUniqueID, 1) -} - -// lastInotifyCookie is a monotonically increasing counter for generating unique -// inotify cookies. Must be accessed using atomic ops. -var lastInotifyCookie uint32 - -// hostClock implements ktime.Clock. -type hostClock struct { - ktime.WallRateClock - ktime.NoClockEvents -} - -// Now implements ktime.Clock.Now. -func (hostClock) Now() ktime.Time { - return ktime.FromNanoseconds(time.Now().UnixNano()) -} - -// RegisterValue registers additional values with this test context. Useful for -// providing values from external packages that contexttest can't depend on. -func (t *TestContext) RegisterValue(key, value interface{}) { - t.otherValues[key] = value -} - -// Value implements context.Context. -func (t *TestContext) Value(key interface{}) interface{} { - switch key { - case auth.CtxCredentials: - return t.creds - case limits.CtxLimits: - return t.l - case pgalloc.CtxMemoryFile: - return t.mf - case pgalloc.CtxMemoryFileProvider: - return t - case platform.CtxPlatform: - return t.platform - case uniqueid.CtxGlobalUniqueID: - return (*globalUniqueIDProvider).UniqueID(nil) - case uniqueid.CtxGlobalUniqueIDProvider: - return &globalUniqueIDProvider{} - case uniqueid.CtxInotifyCookie: - return atomic.AddUint32(&lastInotifyCookie, 1) - case ktime.CtxRealtimeClock: - return hostClock{} - default: - if val, ok := t.otherValues[key]; ok { - return val - } - return t.Context.Value(key) - } -} - -// MemoryFile implements pgalloc.MemoryFileProvider.MemoryFile. -func (t *TestContext) MemoryFile() *pgalloc.MemoryFile { - return t.mf -} - -// RootContext returns a Context that may be used in tests that need root -// credentials. Uses ptrace as the platform.Platform. -func RootContext(tb testing.TB) context.Context { - return WithCreds(Context(tb), auth.NewRootCredentials(auth.NewRootUserNamespace())) -} - -// WithCreds returns a copy of ctx carrying creds. -func WithCreds(ctx context.Context, creds *auth.Credentials) context.Context { - return &authContext{ctx, creds} -} - -type authContext struct { - context.Context - creds *auth.Credentials -} - -// Value implements context.Context. -func (ac *authContext) Value(key interface{}) interface{} { - switch key { - case auth.CtxCredentials: - return ac.creds - default: - return ac.Context.Value(key) - } -} - -// WithLimitSet returns a copy of ctx carrying l. -func WithLimitSet(ctx context.Context, l *limits.LimitSet) context.Context { - return limitContext{ctx, l} -} - -type limitContext struct { - context.Context - l *limits.LimitSet -} - -// Value implements context.Context. -func (lc limitContext) Value(key interface{}) interface{} { - switch key { - case limits.CtxLimits: - return lc.l - default: - return lc.Context.Value(key) - } -} diff --git a/pkg/sentry/contexttest/BUILD b/pkg/sentry/contexttest/BUILD new file mode 100644 index 000000000..6f4c86684 --- /dev/null +++ b/pkg/sentry/contexttest/BUILD @@ -0,0 +1,21 @@ +load("//tools:defs.bzl", "go_library") + +package(licenses = ["notice"]) + +go_library( + name = "contexttest", + testonly = 1, + srcs = ["contexttest.go"], + visibility = ["//pkg/sentry:internal"], + deps = [ + "//pkg/context", + "//pkg/memutil", + "//pkg/sentry/kernel/auth", + "//pkg/sentry/kernel/time", + "//pkg/sentry/limits", + "//pkg/sentry/pgalloc", + "//pkg/sentry/platform", + "//pkg/sentry/platform/ptrace", + "//pkg/sentry/uniqueid", + ], +) diff --git a/pkg/sentry/contexttest/contexttest.go b/pkg/sentry/contexttest/contexttest.go new file mode 100644 index 000000000..031fc64ec --- /dev/null +++ b/pkg/sentry/contexttest/contexttest.go @@ -0,0 +1,188 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// Package contexttest builds a test context.Context. +package contexttest + +import ( + "os" + "sync/atomic" + "testing" + "time" + + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/memutil" + "gvisor.dev/gvisor/pkg/sentry/kernel/auth" + ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" + "gvisor.dev/gvisor/pkg/sentry/limits" + "gvisor.dev/gvisor/pkg/sentry/pgalloc" + "gvisor.dev/gvisor/pkg/sentry/platform" + "gvisor.dev/gvisor/pkg/sentry/platform/ptrace" + "gvisor.dev/gvisor/pkg/sentry/uniqueid" +) + +// Context returns a Context that may be used in tests. Uses ptrace as the +// platform.Platform. +// +// Note that some filesystems may require a minimal kernel for testing, which +// this test context does not provide. For such tests, see kernel/contexttest. +func Context(tb testing.TB) context.Context { + const memfileName = "contexttest-memory" + memfd, err := memutil.CreateMemFD(memfileName, 0) + if err != nil { + tb.Fatalf("error creating application memory file: %v", err) + } + memfile := os.NewFile(uintptr(memfd), memfileName) + mf, err := pgalloc.NewMemoryFile(memfile, pgalloc.MemoryFileOpts{}) + if err != nil { + memfile.Close() + tb.Fatalf("error creating pgalloc.MemoryFile: %v", err) + } + p, err := ptrace.New() + if err != nil { + tb.Fatal(err) + } + // Test usage of context.Background is fine. + return &TestContext{ + Context: context.Background(), + l: limits.NewLimitSet(), + mf: mf, + platform: p, + creds: auth.NewAnonymousCredentials(), + otherValues: make(map[interface{}]interface{}), + } +} + +// TestContext represents a context with minimal functionality suitable for +// running tests. +type TestContext struct { + context.Context + l *limits.LimitSet + mf *pgalloc.MemoryFile + platform platform.Platform + creds *auth.Credentials + otherValues map[interface{}]interface{} +} + +// globalUniqueID tracks incremental unique identifiers for tests. +var globalUniqueID uint64 + +// globalUniqueIDProvider implements unix.UniqueIDProvider. +type globalUniqueIDProvider struct{} + +// UniqueID implements unix.UniqueIDProvider.UniqueID. +func (*globalUniqueIDProvider) UniqueID() uint64 { + return atomic.AddUint64(&globalUniqueID, 1) +} + +// lastInotifyCookie is a monotonically increasing counter for generating unique +// inotify cookies. Must be accessed using atomic ops. +var lastInotifyCookie uint32 + +// hostClock implements ktime.Clock. +type hostClock struct { + ktime.WallRateClock + ktime.NoClockEvents +} + +// Now implements ktime.Clock.Now. +func (hostClock) Now() ktime.Time { + return ktime.FromNanoseconds(time.Now().UnixNano()) +} + +// RegisterValue registers additional values with this test context. Useful for +// providing values from external packages that contexttest can't depend on. +func (t *TestContext) RegisterValue(key, value interface{}) { + t.otherValues[key] = value +} + +// Value implements context.Context. +func (t *TestContext) Value(key interface{}) interface{} { + switch key { + case auth.CtxCredentials: + return t.creds + case limits.CtxLimits: + return t.l + case pgalloc.CtxMemoryFile: + return t.mf + case pgalloc.CtxMemoryFileProvider: + return t + case platform.CtxPlatform: + return t.platform + case uniqueid.CtxGlobalUniqueID: + return (*globalUniqueIDProvider).UniqueID(nil) + case uniqueid.CtxGlobalUniqueIDProvider: + return &globalUniqueIDProvider{} + case uniqueid.CtxInotifyCookie: + return atomic.AddUint32(&lastInotifyCookie, 1) + case ktime.CtxRealtimeClock: + return hostClock{} + default: + if val, ok := t.otherValues[key]; ok { + return val + } + return t.Context.Value(key) + } +} + +// MemoryFile implements pgalloc.MemoryFileProvider.MemoryFile. +func (t *TestContext) MemoryFile() *pgalloc.MemoryFile { + return t.mf +} + +// RootContext returns a Context that may be used in tests that need root +// credentials. Uses ptrace as the platform.Platform. +func RootContext(tb testing.TB) context.Context { + return WithCreds(Context(tb), auth.NewRootCredentials(auth.NewRootUserNamespace())) +} + +// WithCreds returns a copy of ctx carrying creds. +func WithCreds(ctx context.Context, creds *auth.Credentials) context.Context { + return &authContext{ctx, creds} +} + +type authContext struct { + context.Context + creds *auth.Credentials +} + +// Value implements context.Context. +func (ac *authContext) Value(key interface{}) interface{} { + switch key { + case auth.CtxCredentials: + return ac.creds + default: + return ac.Context.Value(key) + } +} + +// WithLimitSet returns a copy of ctx carrying l. +func WithLimitSet(ctx context.Context, l *limits.LimitSet) context.Context { + return limitContext{ctx, l} +} + +type limitContext struct { + context.Context + l *limits.LimitSet +} + +// Value implements context.Context. +func (lc limitContext) Value(key interface{}) interface{} { + switch key { + case limits.CtxLimits: + return lc.l + default: + return lc.Context.Value(key) + } +} diff --git a/pkg/sentry/fs/BUILD b/pkg/sentry/fs/BUILD index 605d61dbe..ea85ab33c 100644 --- a/pkg/sentry/fs/BUILD +++ b/pkg/sentry/fs/BUILD @@ -47,13 +47,13 @@ go_library( deps = [ "//pkg/abi/linux", "//pkg/amutex", + "//pkg/context", "//pkg/log", "//pkg/metric", "//pkg/p9", "//pkg/refs", "//pkg/secio", "//pkg/sentry/arch", - "//pkg/sentry/context", "//pkg/sentry/device", "//pkg/sentry/fs/lock", "//pkg/sentry/kernel/auth", @@ -64,10 +64,10 @@ go_library( "//pkg/sentry/socket/unix/transport", "//pkg/sentry/uniqueid", "//pkg/sentry/usage", - "//pkg/sentry/usermem", "//pkg/state", "//pkg/sync", "//pkg/syserror", + "//pkg/usermem", "//pkg/waiter", ], ) @@ -107,14 +107,14 @@ go_test( ], deps = [ ":fs", - "//pkg/sentry/context", + "//pkg/context", "//pkg/sentry/fs/fsutil", "//pkg/sentry/fs/ramfs", "//pkg/sentry/fs/tmpfs", "//pkg/sentry/kernel/contexttest", - "//pkg/sentry/usermem", "//pkg/sync", "//pkg/syserror", + "//pkg/usermem", ], ) @@ -129,7 +129,7 @@ go_test( ], library = ":fs", deps = [ - "//pkg/sentry/context", - "//pkg/sentry/context/contexttest", + "//pkg/context", + "//pkg/sentry/contexttest", ], ) diff --git a/pkg/sentry/fs/anon/BUILD b/pkg/sentry/fs/anon/BUILD index c14e5405e..aedcecfa1 100644 --- a/pkg/sentry/fs/anon/BUILD +++ b/pkg/sentry/fs/anon/BUILD @@ -11,10 +11,10 @@ go_library( visibility = ["//pkg/sentry:internal"], deps = [ "//pkg/abi/linux", - "//pkg/sentry/context", + "//pkg/context", "//pkg/sentry/device", "//pkg/sentry/fs", "//pkg/sentry/fs/fsutil", - "//pkg/sentry/usermem", + "//pkg/usermem", ], ) diff --git a/pkg/sentry/fs/anon/anon.go b/pkg/sentry/fs/anon/anon.go index 7323c7222..5c421f5fb 100644 --- a/pkg/sentry/fs/anon/anon.go +++ b/pkg/sentry/fs/anon/anon.go @@ -18,10 +18,10 @@ package anon import ( "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // NewInode constructs an anonymous Inode that is not associated diff --git a/pkg/sentry/fs/attr.go b/pkg/sentry/fs/attr.go index 4f3d6410e..fa9e7d517 100644 --- a/pkg/sentry/fs/attr.go +++ b/pkg/sentry/fs/attr.go @@ -20,8 +20,8 @@ import ( "syscall" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/p9" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" ) diff --git a/pkg/sentry/fs/context.go b/pkg/sentry/fs/context.go index dd427de5d..0fbd60056 100644 --- a/pkg/sentry/fs/context.go +++ b/pkg/sentry/fs/context.go @@ -16,7 +16,7 @@ package fs import ( "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" ) diff --git a/pkg/sentry/fs/copy_up.go b/pkg/sentry/fs/copy_up.go index e03e3e417..f6c79e51b 100644 --- a/pkg/sentry/fs/copy_up.go +++ b/pkg/sentry/fs/copy_up.go @@ -19,12 +19,12 @@ import ( "io" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/log" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/memmap" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // copyUp copies a file in an overlay from a lower filesystem to an diff --git a/pkg/sentry/fs/copy_up_test.go b/pkg/sentry/fs/copy_up_test.go index 738580c5f..91792d9fe 100644 --- a/pkg/sentry/fs/copy_up_test.go +++ b/pkg/sentry/fs/copy_up_test.go @@ -24,8 +24,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/fs" _ "gvisor.dev/gvisor/pkg/sentry/fs/tmpfs" "gvisor.dev/gvisor/pkg/sentry/kernel/contexttest" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" + "gvisor.dev/gvisor/pkg/usermem" ) const ( diff --git a/pkg/sentry/fs/dev/BUILD b/pkg/sentry/fs/dev/BUILD index 0c7247bd7..4c4b7d5cc 100644 --- a/pkg/sentry/fs/dev/BUILD +++ b/pkg/sentry/fs/dev/BUILD @@ -16,8 +16,9 @@ go_library( visibility = ["//pkg/sentry:internal"], deps = [ "//pkg/abi/linux", + "//pkg/context", "//pkg/rand", - "//pkg/sentry/context", + "//pkg/safemem", "//pkg/sentry/device", "//pkg/sentry/fs", "//pkg/sentry/fs/fsutil", @@ -26,9 +27,8 @@ go_library( "//pkg/sentry/memmap", "//pkg/sentry/mm", "//pkg/sentry/pgalloc", - "//pkg/sentry/safemem", - "//pkg/sentry/usermem", "//pkg/syserror", + "//pkg/usermem", "//pkg/waiter", ], ) diff --git a/pkg/sentry/fs/dev/dev.go b/pkg/sentry/fs/dev/dev.go index f739c476c..35bd23991 100644 --- a/pkg/sentry/fs/dev/dev.go +++ b/pkg/sentry/fs/dev/dev.go @@ -18,11 +18,11 @@ package dev import ( "math" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/ramfs" "gvisor.dev/gvisor/pkg/sentry/fs/tmpfs" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // Memory device numbers are from Linux's drivers/char/mem.c diff --git a/pkg/sentry/fs/dev/fs.go b/pkg/sentry/fs/dev/fs.go index 55f8af704..5e518fb63 100644 --- a/pkg/sentry/fs/dev/fs.go +++ b/pkg/sentry/fs/dev/fs.go @@ -15,7 +15,7 @@ package dev import ( - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" ) diff --git a/pkg/sentry/fs/dev/full.go b/pkg/sentry/fs/dev/full.go index 07e0ea010..deb9c6ad8 100644 --- a/pkg/sentry/fs/dev/full.go +++ b/pkg/sentry/fs/dev/full.go @@ -16,11 +16,11 @@ package dev import ( "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/fs/dev/null.go b/pkg/sentry/fs/dev/null.go index 4404b97ef..aec33d0d9 100644 --- a/pkg/sentry/fs/dev/null.go +++ b/pkg/sentry/fs/dev/null.go @@ -16,7 +16,7 @@ package dev import ( "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/memmap" diff --git a/pkg/sentry/fs/dev/random.go b/pkg/sentry/fs/dev/random.go index 49cb92f6e..2a9bbeb18 100644 --- a/pkg/sentry/fs/dev/random.go +++ b/pkg/sentry/fs/dev/random.go @@ -16,12 +16,12 @@ package dev import ( "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/rand" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" - "gvisor.dev/gvisor/pkg/sentry/safemem" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/fs/dev/tty.go b/pkg/sentry/fs/dev/tty.go index 87d80e292..760ca563d 100644 --- a/pkg/sentry/fs/dev/tty.go +++ b/pkg/sentry/fs/dev/tty.go @@ -16,7 +16,7 @@ package dev import ( "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/waiter" diff --git a/pkg/sentry/fs/dirent.go b/pkg/sentry/fs/dirent.go index 31fc4d87b..acab0411a 100644 --- a/pkg/sentry/fs/dirent.go +++ b/pkg/sentry/fs/dirent.go @@ -22,8 +22,8 @@ import ( "syscall" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/refs" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" "gvisor.dev/gvisor/pkg/sentry/uniqueid" diff --git a/pkg/sentry/fs/dirent_refs_test.go b/pkg/sentry/fs/dirent_refs_test.go index 47bc72a88..98d69c6f2 100644 --- a/pkg/sentry/fs/dirent_refs_test.go +++ b/pkg/sentry/fs/dirent_refs_test.go @@ -18,8 +18,8 @@ import ( "syscall" "testing" - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/sentry/contexttest" ) func newMockDirInode(ctx context.Context, cache *DirentCache) *Inode { diff --git a/pkg/sentry/fs/fdpipe/BUILD b/pkg/sentry/fs/fdpipe/BUILD index 25ef96299..1d09e983c 100644 --- a/pkg/sentry/fs/fdpipe/BUILD +++ b/pkg/sentry/fs/fdpipe/BUILD @@ -12,17 +12,17 @@ go_library( imports = ["gvisor.dev/gvisor/pkg/sentry/fs"], visibility = ["//pkg/sentry:internal"], deps = [ + "//pkg/context", "//pkg/fd", "//pkg/fdnotifier", "//pkg/log", + "//pkg/safemem", "//pkg/secio", - "//pkg/sentry/context", "//pkg/sentry/fs", "//pkg/sentry/fs/fsutil", - "//pkg/sentry/safemem", - "//pkg/sentry/usermem", "//pkg/sync", "//pkg/syserror", + "//pkg/usermem", "//pkg/waiter", ], ) @@ -36,13 +36,13 @@ go_test( ], library = ":fdpipe", deps = [ + "//pkg/context", "//pkg/fd", "//pkg/fdnotifier", - "//pkg/sentry/context", - "//pkg/sentry/context/contexttest", + "//pkg/sentry/contexttest", "//pkg/sentry/fs", - "//pkg/sentry/usermem", "//pkg/syserror", + "//pkg/usermem", "@com_github_google_uuid//:go_default_library", ], ) diff --git a/pkg/sentry/fs/fdpipe/pipe.go b/pkg/sentry/fs/fdpipe/pipe.go index 5b6cfeb0a..9fce177ad 100644 --- a/pkg/sentry/fs/fdpipe/pipe.go +++ b/pkg/sentry/fs/fdpipe/pipe.go @@ -19,17 +19,17 @@ import ( "os" "syscall" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fd" "gvisor.dev/gvisor/pkg/fdnotifier" "gvisor.dev/gvisor/pkg/log" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/secio" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" - "gvisor.dev/gvisor/pkg/sentry/safemem" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/fs/fdpipe/pipe_opener.go b/pkg/sentry/fs/fdpipe/pipe_opener.go index 64b558975..0c3595998 100644 --- a/pkg/sentry/fs/fdpipe/pipe_opener.go +++ b/pkg/sentry/fs/fdpipe/pipe_opener.go @@ -20,8 +20,8 @@ import ( "syscall" "time" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fd" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/syserror" ) diff --git a/pkg/sentry/fs/fdpipe/pipe_opener_test.go b/pkg/sentry/fs/fdpipe/pipe_opener_test.go index 577445148..e556da48a 100644 --- a/pkg/sentry/fs/fdpipe/pipe_opener_test.go +++ b/pkg/sentry/fs/fdpipe/pipe_opener_test.go @@ -26,12 +26,12 @@ import ( "github.com/google/uuid" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fd" - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/sentry/fs" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) type hostOpener struct { diff --git a/pkg/sentry/fs/fdpipe/pipe_state.go b/pkg/sentry/fs/fdpipe/pipe_state.go index cee87f726..af8230a7d 100644 --- a/pkg/sentry/fs/fdpipe/pipe_state.go +++ b/pkg/sentry/fs/fdpipe/pipe_state.go @@ -18,7 +18,7 @@ import ( "fmt" "io/ioutil" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sync" ) diff --git a/pkg/sentry/fs/fdpipe/pipe_test.go b/pkg/sentry/fs/fdpipe/pipe_test.go index 69abc1e71..5aff0cc95 100644 --- a/pkg/sentry/fs/fdpipe/pipe_test.go +++ b/pkg/sentry/fs/fdpipe/pipe_test.go @@ -23,10 +23,10 @@ import ( "gvisor.dev/gvisor/pkg/fd" "gvisor.dev/gvisor/pkg/fdnotifier" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/sentry/fs" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) func singlePipeFD() (int, error) { diff --git a/pkg/sentry/fs/file.go b/pkg/sentry/fs/file.go index 7c4586296..ca3466f4f 100644 --- a/pkg/sentry/fs/file.go +++ b/pkg/sentry/fs/file.go @@ -20,16 +20,16 @@ import ( "time" "gvisor.dev/gvisor/pkg/amutex" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/metric" "gvisor.dev/gvisor/pkg/refs" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs/lock" "gvisor.dev/gvisor/pkg/sentry/limits" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/uniqueid" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/fs/file_operations.go b/pkg/sentry/fs/file_operations.go index b88303f17..beba0f771 100644 --- a/pkg/sentry/fs/file_operations.go +++ b/pkg/sentry/fs/file_operations.go @@ -17,10 +17,10 @@ package fs import ( "io" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/memmap" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/fs/file_overlay.go b/pkg/sentry/fs/file_overlay.go index 8991207b4..dcc1df38f 100644 --- a/pkg/sentry/fs/file_overlay.go +++ b/pkg/sentry/fs/file_overlay.go @@ -17,13 +17,13 @@ package fs import ( "io" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/refs" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/memmap" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/fs/file_overlay_test.go b/pkg/sentry/fs/file_overlay_test.go index 2fb824d5c..02538bb4f 100644 --- a/pkg/sentry/fs/file_overlay_test.go +++ b/pkg/sentry/fs/file_overlay_test.go @@ -18,7 +18,7 @@ import ( "reflect" "testing" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/fs/ramfs" diff --git a/pkg/sentry/fs/filesystems.go b/pkg/sentry/fs/filesystems.go index c5b51620a..084da2a8d 100644 --- a/pkg/sentry/fs/filesystems.go +++ b/pkg/sentry/fs/filesystems.go @@ -19,7 +19,7 @@ import ( "sort" "strings" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sync" ) diff --git a/pkg/sentry/fs/filetest/BUILD b/pkg/sentry/fs/filetest/BUILD index 9a7608cae..a8000e010 100644 --- a/pkg/sentry/fs/filetest/BUILD +++ b/pkg/sentry/fs/filetest/BUILD @@ -8,12 +8,12 @@ go_library( srcs = ["filetest.go"], visibility = ["//pkg/sentry:internal"], deps = [ - "//pkg/sentry/context", - "//pkg/sentry/context/contexttest", + "//pkg/context", + "//pkg/sentry/contexttest", "//pkg/sentry/fs", "//pkg/sentry/fs/anon", "//pkg/sentry/fs/fsutil", - "//pkg/sentry/usermem", + "//pkg/usermem", "//pkg/waiter", ], ) diff --git a/pkg/sentry/fs/filetest/filetest.go b/pkg/sentry/fs/filetest/filetest.go index 22270a494..8049538f2 100644 --- a/pkg/sentry/fs/filetest/filetest.go +++ b/pkg/sentry/fs/filetest/filetest.go @@ -19,12 +19,12 @@ import ( "fmt" "testing" - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/anon" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/fs/fs.go b/pkg/sentry/fs/fs.go index 26abf49e2..bdba6efe5 100644 --- a/pkg/sentry/fs/fs.go +++ b/pkg/sentry/fs/fs.go @@ -54,8 +54,8 @@ package fs import ( + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/log" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sync" ) diff --git a/pkg/sentry/fs/fsutil/BUILD b/pkg/sentry/fs/fsutil/BUILD index 9142f5bdf..4ab2a384f 100644 --- a/pkg/sentry/fs/fsutil/BUILD +++ b/pkg/sentry/fs/fsutil/BUILD @@ -77,22 +77,22 @@ go_library( visibility = ["//pkg/sentry:internal"], deps = [ "//pkg/abi/linux", + "//pkg/context", "//pkg/log", + "//pkg/safemem", "//pkg/sentry/arch", - "//pkg/sentry/context", "//pkg/sentry/device", "//pkg/sentry/fs", "//pkg/sentry/kernel/time", "//pkg/sentry/memmap", "//pkg/sentry/pgalloc", "//pkg/sentry/platform", - "//pkg/sentry/safemem", "//pkg/sentry/socket/unix/transport", "//pkg/sentry/usage", - "//pkg/sentry/usermem", "//pkg/state", "//pkg/sync", "//pkg/syserror", + "//pkg/usermem", "//pkg/waiter", ], ) @@ -106,13 +106,13 @@ go_test( ], library = ":fsutil", deps = [ - "//pkg/sentry/context", - "//pkg/sentry/context/contexttest", + "//pkg/context", + "//pkg/safemem", + "//pkg/sentry/contexttest", "//pkg/sentry/fs", "//pkg/sentry/kernel/time", "//pkg/sentry/memmap", - "//pkg/sentry/safemem", - "//pkg/sentry/usermem", "//pkg/syserror", + "//pkg/usermem", ], ) diff --git a/pkg/sentry/fs/fsutil/dirty_set.go b/pkg/sentry/fs/fsutil/dirty_set.go index 12132680b..c6cd45087 100644 --- a/pkg/sentry/fs/fsutil/dirty_set.go +++ b/pkg/sentry/fs/fsutil/dirty_set.go @@ -17,11 +17,11 @@ package fsutil import ( "math" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/platform" - "gvisor.dev/gvisor/pkg/sentry/safemem" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // DirtySet maps offsets into a memmap.Mappable to DirtyInfo. It is used to diff --git a/pkg/sentry/fs/fsutil/dirty_set_test.go b/pkg/sentry/fs/fsutil/dirty_set_test.go index 75575d994..e3579c23c 100644 --- a/pkg/sentry/fs/fsutil/dirty_set_test.go +++ b/pkg/sentry/fs/fsutil/dirty_set_test.go @@ -19,7 +19,7 @@ import ( "testing" "gvisor.dev/gvisor/pkg/sentry/memmap" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) func TestDirtySet(t *testing.T) { diff --git a/pkg/sentry/fs/fsutil/file.go b/pkg/sentry/fs/fsutil/file.go index fc5b3b1a1..08695391c 100644 --- a/pkg/sentry/fs/fsutil/file.go +++ b/pkg/sentry/fs/fsutil/file.go @@ -17,12 +17,12 @@ package fsutil import ( "io" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/memmap" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/fs/fsutil/file_range_set.go b/pkg/sentry/fs/fsutil/file_range_set.go index f52d712e3..5643cdac9 100644 --- a/pkg/sentry/fs/fsutil/file_range_set.go +++ b/pkg/sentry/fs/fsutil/file_range_set.go @@ -19,13 +19,13 @@ import ( "io" "math" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/pgalloc" "gvisor.dev/gvisor/pkg/sentry/platform" - "gvisor.dev/gvisor/pkg/sentry/safemem" "gvisor.dev/gvisor/pkg/sentry/usage" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // FileRangeSet maps offsets into a memmap.Mappable to offsets into a diff --git a/pkg/sentry/fs/fsutil/host_file_mapper.go b/pkg/sentry/fs/fsutil/host_file_mapper.go index 837fc70b5..67278aa86 100644 --- a/pkg/sentry/fs/fsutil/host_file_mapper.go +++ b/pkg/sentry/fs/fsutil/host_file_mapper.go @@ -19,11 +19,11 @@ import ( "syscall" "gvisor.dev/gvisor/pkg/log" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/platform" - "gvisor.dev/gvisor/pkg/sentry/safemem" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" + "gvisor.dev/gvisor/pkg/usermem" ) // HostFileMapper caches mappings of an arbitrary host file descriptor. It is diff --git a/pkg/sentry/fs/fsutil/host_file_mapper_unsafe.go b/pkg/sentry/fs/fsutil/host_file_mapper_unsafe.go index ad11a0573..2d4778d64 100644 --- a/pkg/sentry/fs/fsutil/host_file_mapper_unsafe.go +++ b/pkg/sentry/fs/fsutil/host_file_mapper_unsafe.go @@ -17,7 +17,7 @@ package fsutil import ( "unsafe" - "gvisor.dev/gvisor/pkg/sentry/safemem" + "gvisor.dev/gvisor/pkg/safemem" ) func (*HostFileMapper) unsafeBlockFromChunkMapping(addr uintptr) safemem.Block { diff --git a/pkg/sentry/fs/fsutil/host_mappable.go b/pkg/sentry/fs/fsutil/host_mappable.go index a625f0e26..78fec553e 100644 --- a/pkg/sentry/fs/fsutil/host_mappable.go +++ b/pkg/sentry/fs/fsutil/host_mappable.go @@ -17,13 +17,13 @@ package fsutil import ( "math" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/platform" - "gvisor.dev/gvisor/pkg/sentry/safemem" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" + "gvisor.dev/gvisor/pkg/usermem" ) // HostMappable implements memmap.Mappable and platform.File over a diff --git a/pkg/sentry/fs/fsutil/inode.go b/pkg/sentry/fs/fsutil/inode.go index df7b74855..252830572 100644 --- a/pkg/sentry/fs/fsutil/inode.go +++ b/pkg/sentry/fs/fsutil/inode.go @@ -16,7 +16,7 @@ package fsutil import ( "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/memmap" diff --git a/pkg/sentry/fs/fsutil/inode_cached.go b/pkg/sentry/fs/fsutil/inode_cached.go index 20a014402..573b8586e 100644 --- a/pkg/sentry/fs/fsutil/inode_cached.go +++ b/pkg/sentry/fs/fsutil/inode_cached.go @@ -18,18 +18,18 @@ import ( "fmt" "io" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/log" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel/time" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/pgalloc" "gvisor.dev/gvisor/pkg/sentry/platform" - "gvisor.dev/gvisor/pkg/sentry/safemem" "gvisor.dev/gvisor/pkg/sentry/usage" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" + "gvisor.dev/gvisor/pkg/usermem" ) // Lock order (compare the lock order model in mm/mm.go): diff --git a/pkg/sentry/fs/fsutil/inode_cached_test.go b/pkg/sentry/fs/fsutil/inode_cached_test.go index 129f314c8..1547584c5 100644 --- a/pkg/sentry/fs/fsutil/inode_cached_test.go +++ b/pkg/sentry/fs/fsutil/inode_cached_test.go @@ -19,14 +19,14 @@ import ( "io" "testing" - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/safemem" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/sentry/fs" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/memmap" - "gvisor.dev/gvisor/pkg/sentry/safemem" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) type noopBackingFile struct{} diff --git a/pkg/sentry/fs/gofer/BUILD b/pkg/sentry/fs/gofer/BUILD index cf48e7c03..971d3718e 100644 --- a/pkg/sentry/fs/gofer/BUILD +++ b/pkg/sentry/fs/gofer/BUILD @@ -24,13 +24,14 @@ go_library( visibility = ["//pkg/sentry:internal"], deps = [ "//pkg/abi/linux", + "//pkg/context", "//pkg/fd", "//pkg/log", "//pkg/metric", "//pkg/p9", "//pkg/refs", + "//pkg/safemem", "//pkg/secio", - "//pkg/sentry/context", "//pkg/sentry/device", "//pkg/sentry/fs", "//pkg/sentry/fs/fdpipe", @@ -39,13 +40,12 @@ go_library( "//pkg/sentry/kernel/auth", "//pkg/sentry/kernel/time", "//pkg/sentry/memmap", - "//pkg/sentry/safemem", "//pkg/sentry/socket/unix/transport", - "//pkg/sentry/usermem", "//pkg/sync", "//pkg/syserr", "//pkg/syserror", "//pkg/unet", + "//pkg/usermem", "//pkg/waiter", ], ) @@ -56,10 +56,10 @@ go_test( srcs = ["gofer_test.go"], library = ":gofer", deps = [ + "//pkg/context", "//pkg/p9", "//pkg/p9/p9test", - "//pkg/sentry/context", - "//pkg/sentry/context/contexttest", + "//pkg/sentry/contexttest", "//pkg/sentry/fs", ], ) diff --git a/pkg/sentry/fs/gofer/attr.go b/pkg/sentry/fs/gofer/attr.go index 4848e2374..71cccdc34 100644 --- a/pkg/sentry/fs/gofer/attr.go +++ b/pkg/sentry/fs/gofer/attr.go @@ -17,12 +17,12 @@ package gofer import ( "syscall" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/p9" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // getattr returns the 9p attributes of the p9.File. On success, Mode, Size, and RDev diff --git a/pkg/sentry/fs/gofer/cache_policy.go b/pkg/sentry/fs/gofer/cache_policy.go index cc11c6339..ebea03c42 100644 --- a/pkg/sentry/fs/gofer/cache_policy.go +++ b/pkg/sentry/fs/gofer/cache_policy.go @@ -17,7 +17,7 @@ package gofer import ( "fmt" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" ) diff --git a/pkg/sentry/fs/gofer/context_file.go b/pkg/sentry/fs/gofer/context_file.go index 2125dafef..3da818aed 100644 --- a/pkg/sentry/fs/gofer/context_file.go +++ b/pkg/sentry/fs/gofer/context_file.go @@ -15,9 +15,9 @@ package gofer import ( + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fd" "gvisor.dev/gvisor/pkg/p9" - "gvisor.dev/gvisor/pkg/sentry/context" ) // contextFile is a wrapper around p9.File that notifies the context that diff --git a/pkg/sentry/fs/gofer/file.go b/pkg/sentry/fs/gofer/file.go index 7960b9c7b..23296f246 100644 --- a/pkg/sentry/fs/gofer/file.go +++ b/pkg/sentry/fs/gofer/file.go @@ -19,16 +19,16 @@ import ( "syscall" "time" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/log" "gvisor.dev/gvisor/pkg/metric" "gvisor.dev/gvisor/pkg/p9" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/device" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/memmap" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/fs/gofer/file_state.go b/pkg/sentry/fs/gofer/file_state.go index bb8312849..ff96b28ba 100644 --- a/pkg/sentry/fs/gofer/file_state.go +++ b/pkg/sentry/fs/gofer/file_state.go @@ -17,7 +17,7 @@ package gofer import ( "fmt" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" ) diff --git a/pkg/sentry/fs/gofer/fs.go b/pkg/sentry/fs/gofer/fs.go index cf96dd9fa..9d41fcbdb 100644 --- a/pkg/sentry/fs/gofer/fs.go +++ b/pkg/sentry/fs/gofer/fs.go @@ -20,8 +20,8 @@ import ( "fmt" "strconv" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/p9" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" ) diff --git a/pkg/sentry/fs/gofer/gofer_test.go b/pkg/sentry/fs/gofer/gofer_test.go index 7fc3c32ae..0c2f89ae8 100644 --- a/pkg/sentry/fs/gofer/gofer_test.go +++ b/pkg/sentry/fs/gofer/gofer_test.go @@ -20,10 +20,10 @@ import ( "testing" "time" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/p9" "gvisor.dev/gvisor/pkg/p9/p9test" - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/sentry/fs" ) diff --git a/pkg/sentry/fs/gofer/handles.go b/pkg/sentry/fs/gofer/handles.go index b86c49b39..9f7c3e89f 100644 --- a/pkg/sentry/fs/gofer/handles.go +++ b/pkg/sentry/fs/gofer/handles.go @@ -17,14 +17,14 @@ package gofer import ( "io" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fd" "gvisor.dev/gvisor/pkg/log" "gvisor.dev/gvisor/pkg/p9" "gvisor.dev/gvisor/pkg/refs" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/secio" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" - "gvisor.dev/gvisor/pkg/sentry/safemem" ) // handles are the open handles of a gofer file. They are reference counted to diff --git a/pkg/sentry/fs/gofer/inode.go b/pkg/sentry/fs/gofer/inode.go index 98d1a8a48..ac28174d2 100644 --- a/pkg/sentry/fs/gofer/inode.go +++ b/pkg/sentry/fs/gofer/inode.go @@ -19,17 +19,17 @@ import ( "syscall" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fd" "gvisor.dev/gvisor/pkg/log" "gvisor.dev/gvisor/pkg/p9" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/device" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fdpipe" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/fs/host" "gvisor.dev/gvisor/pkg/sentry/memmap" - "gvisor.dev/gvisor/pkg/sentry/safemem" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" ) diff --git a/pkg/sentry/fs/gofer/inode_state.go b/pkg/sentry/fs/gofer/inode_state.go index 0b2eedb7c..238f7804c 100644 --- a/pkg/sentry/fs/gofer/inode_state.go +++ b/pkg/sentry/fs/gofer/inode_state.go @@ -20,8 +20,8 @@ import ( "path/filepath" "strings" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/p9" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/device" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel/time" diff --git a/pkg/sentry/fs/gofer/path.go b/pkg/sentry/fs/gofer/path.go index c09f3b71c..0c1be05ef 100644 --- a/pkg/sentry/fs/gofer/path.go +++ b/pkg/sentry/fs/gofer/path.go @@ -18,9 +18,9 @@ import ( "fmt" "syscall" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/log" "gvisor.dev/gvisor/pkg/p9" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/device" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" diff --git a/pkg/sentry/fs/gofer/session.go b/pkg/sentry/fs/gofer/session.go index edc796ce0..498c4645a 100644 --- a/pkg/sentry/fs/gofer/session.go +++ b/pkg/sentry/fs/gofer/session.go @@ -17,9 +17,9 @@ package gofer import ( "fmt" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/p9" "gvisor.dev/gvisor/pkg/refs" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/device" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" diff --git a/pkg/sentry/fs/gofer/session_state.go b/pkg/sentry/fs/gofer/session_state.go index d045e04ff..0285c5361 100644 --- a/pkg/sentry/fs/gofer/session_state.go +++ b/pkg/sentry/fs/gofer/session_state.go @@ -17,8 +17,8 @@ package gofer import ( "fmt" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/p9" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/unet" ) diff --git a/pkg/sentry/fs/gofer/socket.go b/pkg/sentry/fs/gofer/socket.go index a45a8f36c..376cfce2c 100644 --- a/pkg/sentry/fs/gofer/socket.go +++ b/pkg/sentry/fs/gofer/socket.go @@ -16,9 +16,9 @@ package gofer import ( "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/log" "gvisor.dev/gvisor/pkg/p9" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/host" "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" diff --git a/pkg/sentry/fs/gofer/util.go b/pkg/sentry/fs/gofer/util.go index 848e6812b..2d8d3a2ea 100644 --- a/pkg/sentry/fs/gofer/util.go +++ b/pkg/sentry/fs/gofer/util.go @@ -17,8 +17,8 @@ package gofer import ( "syscall" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/p9" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" ) diff --git a/pkg/sentry/fs/host/BUILD b/pkg/sentry/fs/host/BUILD index f586f47c1..21003ea45 100644 --- a/pkg/sentry/fs/host/BUILD +++ b/pkg/sentry/fs/host/BUILD @@ -27,13 +27,14 @@ go_library( visibility = ["//pkg/sentry:internal"], deps = [ "//pkg/abi/linux", + "//pkg/context", "//pkg/fd", "//pkg/fdnotifier", "//pkg/log", "//pkg/refs", + "//pkg/safemem", "//pkg/secio", "//pkg/sentry/arch", - "//pkg/sentry/context", "//pkg/sentry/device", "//pkg/sentry/fs", "//pkg/sentry/fs/fsutil", @@ -41,18 +42,17 @@ go_library( "//pkg/sentry/kernel/auth", "//pkg/sentry/kernel/time", "//pkg/sentry/memmap", - "//pkg/sentry/safemem", "//pkg/sentry/socket/control", "//pkg/sentry/socket/unix", "//pkg/sentry/socket/unix/transport", "//pkg/sentry/unimpl", "//pkg/sentry/uniqueid", - "//pkg/sentry/usermem", "//pkg/sync", "//pkg/syserr", "//pkg/syserror", "//pkg/tcpip", "//pkg/unet", + "//pkg/usermem", "//pkg/waiter", ], ) @@ -69,17 +69,17 @@ go_test( ], library = ":host", deps = [ + "//pkg/context", "//pkg/fd", "//pkg/fdnotifier", - "//pkg/sentry/context", - "//pkg/sentry/context/contexttest", + "//pkg/sentry/contexttest", "//pkg/sentry/fs", "//pkg/sentry/kernel/time", "//pkg/sentry/socket", "//pkg/sentry/socket/unix/transport", - "//pkg/sentry/usermem", "//pkg/syserr", "//pkg/tcpip", + "//pkg/usermem", "//pkg/waiter", ], ) diff --git a/pkg/sentry/fs/host/control.go b/pkg/sentry/fs/host/control.go index 5532ff5a0..1658979fc 100644 --- a/pkg/sentry/fs/host/control.go +++ b/pkg/sentry/fs/host/control.go @@ -17,7 +17,7 @@ package host import ( "syscall" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/socket/control" "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" diff --git a/pkg/sentry/fs/host/file.go b/pkg/sentry/fs/host/file.go index f6c626f2c..e08f56d04 100644 --- a/pkg/sentry/fs/host/file.go +++ b/pkg/sentry/fs/host/file.go @@ -18,17 +18,17 @@ import ( "fmt" "syscall" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fd" "gvisor.dev/gvisor/pkg/fdnotifier" "gvisor.dev/gvisor/pkg/log" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/secio" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/memmap" - "gvisor.dev/gvisor/pkg/sentry/safemem" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/fs/host/fs.go b/pkg/sentry/fs/host/fs.go index 68d2697c0..d3e8e3a36 100644 --- a/pkg/sentry/fs/host/fs.go +++ b/pkg/sentry/fs/host/fs.go @@ -23,8 +23,8 @@ import ( "strconv" "strings" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/log" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" ) diff --git a/pkg/sentry/fs/host/fs_test.go b/pkg/sentry/fs/host/fs_test.go index c6852ee30..3111d2df9 100644 --- a/pkg/sentry/fs/host/fs_test.go +++ b/pkg/sentry/fs/host/fs_test.go @@ -23,8 +23,8 @@ import ( "sort" "testing" - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/sentry/fs" ) diff --git a/pkg/sentry/fs/host/inode.go b/pkg/sentry/fs/host/inode.go index 873a1c52d..6fa39caab 100644 --- a/pkg/sentry/fs/host/inode.go +++ b/pkg/sentry/fs/host/inode.go @@ -18,14 +18,14 @@ import ( "syscall" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fd" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/secio" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/device" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/memmap" - "gvisor.dev/gvisor/pkg/sentry/safemem" "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" diff --git a/pkg/sentry/fs/host/inode_state.go b/pkg/sentry/fs/host/inode_state.go index b267ec305..299e0e0b0 100644 --- a/pkg/sentry/fs/host/inode_state.go +++ b/pkg/sentry/fs/host/inode_state.go @@ -18,7 +18,7 @@ import ( "fmt" "syscall" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/device" "gvisor.dev/gvisor/pkg/sentry/fs" ) diff --git a/pkg/sentry/fs/host/inode_test.go b/pkg/sentry/fs/host/inode_test.go index 2d959f10d..7221bc825 100644 --- a/pkg/sentry/fs/host/inode_test.go +++ b/pkg/sentry/fs/host/inode_test.go @@ -21,7 +21,7 @@ import ( "syscall" "testing" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/sentry/fs" ) diff --git a/pkg/sentry/fs/host/socket.go b/pkg/sentry/fs/host/socket.go index c076d5bdd..06fc2d80a 100644 --- a/pkg/sentry/fs/host/socket.go +++ b/pkg/sentry/fs/host/socket.go @@ -19,11 +19,11 @@ import ( "syscall" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fd" "gvisor.dev/gvisor/pkg/fdnotifier" "gvisor.dev/gvisor/pkg/log" "gvisor.dev/gvisor/pkg/refs" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/socket/control" unixsocket "gvisor.dev/gvisor/pkg/sentry/socket/unix" diff --git a/pkg/sentry/fs/host/socket_test.go b/pkg/sentry/fs/host/socket_test.go index 68b38fd1c..eb4afe520 100644 --- a/pkg/sentry/fs/host/socket_test.go +++ b/pkg/sentry/fs/host/socket_test.go @@ -21,13 +21,13 @@ import ( "gvisor.dev/gvisor/pkg/fd" "gvisor.dev/gvisor/pkg/fdnotifier" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/sentry/contexttest" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/socket" "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserr" "gvisor.dev/gvisor/pkg/tcpip" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/fs/host/tty.go b/pkg/sentry/fs/host/tty.go index 753ef8cd6..3f218b4a7 100644 --- a/pkg/sentry/fs/host/tty.go +++ b/pkg/sentry/fs/host/tty.go @@ -16,14 +16,14 @@ package host import ( "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/unimpl" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // TTYFileOperations implements fs.FileOperations for a host file descriptor diff --git a/pkg/sentry/fs/host/wait_test.go b/pkg/sentry/fs/host/wait_test.go index 88d24d693..d49c3a635 100644 --- a/pkg/sentry/fs/host/wait_test.go +++ b/pkg/sentry/fs/host/wait_test.go @@ -19,7 +19,7 @@ import ( "testing" "time" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/fs/inode.go b/pkg/sentry/fs/inode.go index e4cf5a570..b66c091ab 100644 --- a/pkg/sentry/fs/inode.go +++ b/pkg/sentry/fs/inode.go @@ -16,10 +16,10 @@ package fs import ( "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/log" "gvisor.dev/gvisor/pkg/metric" "gvisor.dev/gvisor/pkg/refs" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs/lock" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/memmap" diff --git a/pkg/sentry/fs/inode_operations.go b/pkg/sentry/fs/inode_operations.go index 13261cb81..70f2eae96 100644 --- a/pkg/sentry/fs/inode_operations.go +++ b/pkg/sentry/fs/inode_operations.go @@ -17,7 +17,7 @@ package fs import ( "errors" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" diff --git a/pkg/sentry/fs/inode_overlay.go b/pkg/sentry/fs/inode_overlay.go index c477de837..4729b4aac 100644 --- a/pkg/sentry/fs/inode_overlay.go +++ b/pkg/sentry/fs/inode_overlay.go @@ -19,8 +19,8 @@ import ( "strings" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/log" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" "gvisor.dev/gvisor/pkg/syserror" ) diff --git a/pkg/sentry/fs/inode_overlay_test.go b/pkg/sentry/fs/inode_overlay_test.go index 493d98c36..389c219d6 100644 --- a/pkg/sentry/fs/inode_overlay_test.go +++ b/pkg/sentry/fs/inode_overlay_test.go @@ -17,7 +17,7 @@ package fs_test import ( "testing" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/fs/ramfs" diff --git a/pkg/sentry/fs/inotify.go b/pkg/sentry/fs/inotify.go index cc7dd1c92..928c90aa0 100644 --- a/pkg/sentry/fs/inotify.go +++ b/pkg/sentry/fs/inotify.go @@ -19,13 +19,13 @@ import ( "sync/atomic" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/uniqueid" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/fs/inotify_event.go b/pkg/sentry/fs/inotify_event.go index 9f70a3e82..686e1b1cd 100644 --- a/pkg/sentry/fs/inotify_event.go +++ b/pkg/sentry/fs/inotify_event.go @@ -18,8 +18,8 @@ import ( "bytes" "fmt" - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/usermem" ) // inotifyEventBaseSize is the base size of linux's struct inotify_event. This diff --git a/pkg/sentry/fs/mock.go b/pkg/sentry/fs/mock.go index 7a24c6f1b..1d6ea5736 100644 --- a/pkg/sentry/fs/mock.go +++ b/pkg/sentry/fs/mock.go @@ -15,7 +15,7 @@ package fs import ( - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/syserror" ) diff --git a/pkg/sentry/fs/mount.go b/pkg/sentry/fs/mount.go index 7a9692800..37bae6810 100644 --- a/pkg/sentry/fs/mount.go +++ b/pkg/sentry/fs/mount.go @@ -19,8 +19,8 @@ import ( "fmt" "sync/atomic" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/refs" - "gvisor.dev/gvisor/pkg/sentry/context" ) // DirentOperations provide file systems greater control over how long a Dirent diff --git a/pkg/sentry/fs/mount_overlay.go b/pkg/sentry/fs/mount_overlay.go index 299712cd7..78e35b1e6 100644 --- a/pkg/sentry/fs/mount_overlay.go +++ b/pkg/sentry/fs/mount_overlay.go @@ -15,7 +15,7 @@ package fs import ( - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" ) // overlayMountSourceOperations implements MountSourceOperations for an overlay diff --git a/pkg/sentry/fs/mount_test.go b/pkg/sentry/fs/mount_test.go index 0b84732aa..e672a438c 100644 --- a/pkg/sentry/fs/mount_test.go +++ b/pkg/sentry/fs/mount_test.go @@ -18,7 +18,7 @@ import ( "fmt" "testing" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/sentry/contexttest" ) // cacheReallyContains iterates through the dirent cache to determine whether diff --git a/pkg/sentry/fs/mounts.go b/pkg/sentry/fs/mounts.go index a9627a9d1..574a2cc91 100644 --- a/pkg/sentry/fs/mounts.go +++ b/pkg/sentry/fs/mounts.go @@ -22,9 +22,9 @@ import ( "syscall" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/log" "gvisor.dev/gvisor/pkg/refs" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" diff --git a/pkg/sentry/fs/mounts_test.go b/pkg/sentry/fs/mounts_test.go index c4c771f2c..a69b41468 100644 --- a/pkg/sentry/fs/mounts_test.go +++ b/pkg/sentry/fs/mounts_test.go @@ -17,7 +17,7 @@ package fs_test import ( "testing" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/fs/ramfs" diff --git a/pkg/sentry/fs/offset.go b/pkg/sentry/fs/offset.go index f7d844ce7..53b5df175 100644 --- a/pkg/sentry/fs/offset.go +++ b/pkg/sentry/fs/offset.go @@ -17,7 +17,7 @@ package fs import ( "math" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // OffsetPageEnd returns the file offset rounded up to the nearest diff --git a/pkg/sentry/fs/overlay.go b/pkg/sentry/fs/overlay.go index f7702f8f4..a8ae7d81d 100644 --- a/pkg/sentry/fs/overlay.go +++ b/pkg/sentry/fs/overlay.go @@ -18,12 +18,12 @@ import ( "fmt" "strings" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/log" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/memmap" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // The virtual filesystem implements an overlay configuration. For a high-level diff --git a/pkg/sentry/fs/proc/BUILD b/pkg/sentry/fs/proc/BUILD index b06bead41..280093c5e 100644 --- a/pkg/sentry/fs/proc/BUILD +++ b/pkg/sentry/fs/proc/BUILD @@ -29,8 +29,8 @@ go_library( visibility = ["//pkg/sentry:internal"], deps = [ "//pkg/abi/linux", + "//pkg/context", "//pkg/log", - "//pkg/sentry/context", "//pkg/sentry/fs", "//pkg/sentry/fs/fsutil", "//pkg/sentry/fs/proc/device", @@ -46,10 +46,10 @@ go_library( "//pkg/sentry/socket/unix", "//pkg/sentry/socket/unix/transport", "//pkg/sentry/usage", - "//pkg/sentry/usermem", "//pkg/sync", "//pkg/syserror", "//pkg/tcpip/header", + "//pkg/usermem", "//pkg/waiter", ], ) @@ -64,8 +64,8 @@ go_test( library = ":proc", deps = [ "//pkg/abi/linux", - "//pkg/sentry/context", + "//pkg/context", "//pkg/sentry/inet", - "//pkg/sentry/usermem", + "//pkg/usermem", ], ) diff --git a/pkg/sentry/fs/proc/cgroup.go b/pkg/sentry/fs/proc/cgroup.go index c4abe319d..7c1d9e7e9 100644 --- a/pkg/sentry/fs/proc/cgroup.go +++ b/pkg/sentry/fs/proc/cgroup.go @@ -17,7 +17,7 @@ package proc import ( "fmt" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" ) diff --git a/pkg/sentry/fs/proc/cpuinfo.go b/pkg/sentry/fs/proc/cpuinfo.go index df0c4e3a7..c96533401 100644 --- a/pkg/sentry/fs/proc/cpuinfo.go +++ b/pkg/sentry/fs/proc/cpuinfo.go @@ -17,7 +17,7 @@ package proc import ( "bytes" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel" ) diff --git a/pkg/sentry/fs/proc/exec_args.go b/pkg/sentry/fs/proc/exec_args.go index 9aaeb780b..8fe626e1c 100644 --- a/pkg/sentry/fs/proc/exec_args.go +++ b/pkg/sentry/fs/proc/exec_args.go @@ -20,12 +20,12 @@ import ( "io" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/fs/proc/fds.go b/pkg/sentry/fs/proc/fds.go index 2fa3cfa7d..35972e23c 100644 --- a/pkg/sentry/fs/proc/fds.go +++ b/pkg/sentry/fs/proc/fds.go @@ -19,7 +19,7 @@ import ( "sort" "strconv" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/fs/proc/device" diff --git a/pkg/sentry/fs/proc/filesystems.go b/pkg/sentry/fs/proc/filesystems.go index 7b3b974ab..0a58ac34c 100644 --- a/pkg/sentry/fs/proc/filesystems.go +++ b/pkg/sentry/fs/proc/filesystems.go @@ -18,7 +18,7 @@ import ( "bytes" "fmt" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/proc/seqfile" ) diff --git a/pkg/sentry/fs/proc/fs.go b/pkg/sentry/fs/proc/fs.go index 761d24462..daf1ba781 100644 --- a/pkg/sentry/fs/proc/fs.go +++ b/pkg/sentry/fs/proc/fs.go @@ -17,7 +17,7 @@ package proc import ( "fmt" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" ) diff --git a/pkg/sentry/fs/proc/inode.go b/pkg/sentry/fs/proc/inode.go index 723f6b661..d2859a4c2 100644 --- a/pkg/sentry/fs/proc/inode.go +++ b/pkg/sentry/fs/proc/inode.go @@ -16,14 +16,14 @@ package proc import ( "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/fs/proc/device" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/mm" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // LINT.IfChange diff --git a/pkg/sentry/fs/proc/loadavg.go b/pkg/sentry/fs/proc/loadavg.go index d7d2afcb7..139d49c34 100644 --- a/pkg/sentry/fs/proc/loadavg.go +++ b/pkg/sentry/fs/proc/loadavg.go @@ -18,7 +18,7 @@ import ( "bytes" "fmt" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs/proc/seqfile" ) diff --git a/pkg/sentry/fs/proc/meminfo.go b/pkg/sentry/fs/proc/meminfo.go index 313c6a32b..465b47da9 100644 --- a/pkg/sentry/fs/proc/meminfo.go +++ b/pkg/sentry/fs/proc/meminfo.go @@ -18,11 +18,11 @@ import ( "bytes" "fmt" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs/proc/seqfile" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/usage" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // LINT.IfChange diff --git a/pkg/sentry/fs/proc/mounts.go b/pkg/sentry/fs/proc/mounts.go index d4efc86e0..c10888100 100644 --- a/pkg/sentry/fs/proc/mounts.go +++ b/pkg/sentry/fs/proc/mounts.go @@ -20,7 +20,7 @@ import ( "sort" "strings" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/proc/seqfile" "gvisor.dev/gvisor/pkg/sentry/kernel" diff --git a/pkg/sentry/fs/proc/net.go b/pkg/sentry/fs/proc/net.go index bad445f3f..6f2775344 100644 --- a/pkg/sentry/fs/proc/net.go +++ b/pkg/sentry/fs/proc/net.go @@ -22,8 +22,8 @@ import ( "time" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/log" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/proc/seqfile" "gvisor.dev/gvisor/pkg/sentry/fs/ramfs" @@ -33,9 +33,9 @@ import ( "gvisor.dev/gvisor/pkg/sentry/socket" "gvisor.dev/gvisor/pkg/sentry/socket/unix" "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/tcpip/header" + "gvisor.dev/gvisor/pkg/usermem" ) // LINT.IfChange diff --git a/pkg/sentry/fs/proc/proc.go b/pkg/sentry/fs/proc/proc.go index 29867dc3a..c8abb5052 100644 --- a/pkg/sentry/fs/proc/proc.go +++ b/pkg/sentry/fs/proc/proc.go @@ -20,7 +20,7 @@ import ( "sort" "strconv" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/fs/proc/device" diff --git a/pkg/sentry/fs/proc/seqfile/BUILD b/pkg/sentry/fs/proc/seqfile/BUILD index 310d8dd52..21338d912 100644 --- a/pkg/sentry/fs/proc/seqfile/BUILD +++ b/pkg/sentry/fs/proc/seqfile/BUILD @@ -8,14 +8,14 @@ go_library( visibility = ["//pkg/sentry:internal"], deps = [ "//pkg/abi/linux", - "//pkg/sentry/context", + "//pkg/context", "//pkg/sentry/fs", "//pkg/sentry/fs/fsutil", "//pkg/sentry/fs/proc/device", "//pkg/sentry/kernel/time", - "//pkg/sentry/usermem", "//pkg/sync", "//pkg/syserror", + "//pkg/usermem", "//pkg/waiter", ], ) @@ -26,10 +26,10 @@ go_test( srcs = ["seqfile_test.go"], library = ":seqfile", deps = [ - "//pkg/sentry/context", - "//pkg/sentry/context/contexttest", + "//pkg/context", + "//pkg/sentry/contexttest", "//pkg/sentry/fs", "//pkg/sentry/fs/ramfs", - "//pkg/sentry/usermem", + "//pkg/usermem", ], ) diff --git a/pkg/sentry/fs/proc/seqfile/seqfile.go b/pkg/sentry/fs/proc/seqfile/seqfile.go index f9af191d5..6121f0e95 100644 --- a/pkg/sentry/fs/proc/seqfile/seqfile.go +++ b/pkg/sentry/fs/proc/seqfile/seqfile.go @@ -19,14 +19,14 @@ import ( "io" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/fs/proc/device" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/fs/proc/seqfile/seqfile_test.go b/pkg/sentry/fs/proc/seqfile/seqfile_test.go index ebfeee835..98e394569 100644 --- a/pkg/sentry/fs/proc/seqfile/seqfile_test.go +++ b/pkg/sentry/fs/proc/seqfile/seqfile_test.go @@ -20,11 +20,11 @@ import ( "io" "testing" - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/ramfs" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) type seqTest struct { diff --git a/pkg/sentry/fs/proc/stat.go b/pkg/sentry/fs/proc/stat.go index bc5b2bc7b..d4fbd76ac 100644 --- a/pkg/sentry/fs/proc/stat.go +++ b/pkg/sentry/fs/proc/stat.go @@ -19,7 +19,7 @@ import ( "fmt" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs/proc/seqfile" "gvisor.dev/gvisor/pkg/sentry/kernel" ) diff --git a/pkg/sentry/fs/proc/sys.go b/pkg/sentry/fs/proc/sys.go index 2bdcf5f70..f8aad2dbd 100644 --- a/pkg/sentry/fs/proc/sys.go +++ b/pkg/sentry/fs/proc/sys.go @@ -20,13 +20,13 @@ import ( "strconv" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/fs/proc/seqfile" "gvisor.dev/gvisor/pkg/sentry/fs/ramfs" "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/fs/proc/sys_net.go b/pkg/sentry/fs/proc/sys_net.go index b9e8ef35f..0772d4ae4 100644 --- a/pkg/sentry/fs/proc/sys_net.go +++ b/pkg/sentry/fs/proc/sys_net.go @@ -19,14 +19,14 @@ import ( "io" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/fs/proc/device" "gvisor.dev/gvisor/pkg/sentry/fs/ramfs" "gvisor.dev/gvisor/pkg/sentry/inet" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/fs/proc/sys_net_test.go b/pkg/sentry/fs/proc/sys_net_test.go index 6abae7a60..355e83d47 100644 --- a/pkg/sentry/fs/proc/sys_net_test.go +++ b/pkg/sentry/fs/proc/sys_net_test.go @@ -17,9 +17,9 @@ package proc import ( "testing" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/inet" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) func TestQuerySendBufferSize(t *testing.T) { diff --git a/pkg/sentry/fs/proc/task.go b/pkg/sentry/fs/proc/task.go index 7358d6ef9..ca020e11e 100644 --- a/pkg/sentry/fs/proc/task.go +++ b/pkg/sentry/fs/proc/task.go @@ -22,7 +22,7 @@ import ( "strconv" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/fs/proc/device" @@ -32,8 +32,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/limits" "gvisor.dev/gvisor/pkg/sentry/mm" "gvisor.dev/gvisor/pkg/sentry/usage" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/fs/proc/uid_gid_map.go b/pkg/sentry/fs/proc/uid_gid_map.go index 3eacc9265..8d9517b95 100644 --- a/pkg/sentry/fs/proc/uid_gid_map.go +++ b/pkg/sentry/fs/proc/uid_gid_map.go @@ -20,13 +20,13 @@ import ( "io" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/fs/proc/uptime.go b/pkg/sentry/fs/proc/uptime.go index adfe58adb..c0f6fb802 100644 --- a/pkg/sentry/fs/proc/uptime.go +++ b/pkg/sentry/fs/proc/uptime.go @@ -19,12 +19,12 @@ import ( "io" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/fs/proc/version.go b/pkg/sentry/fs/proc/version.go index 27fd5b1cb..35e258ff6 100644 --- a/pkg/sentry/fs/proc/version.go +++ b/pkg/sentry/fs/proc/version.go @@ -17,7 +17,7 @@ package proc import ( "fmt" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs/proc/seqfile" "gvisor.dev/gvisor/pkg/sentry/kernel" ) diff --git a/pkg/sentry/fs/ramfs/BUILD b/pkg/sentry/fs/ramfs/BUILD index 39c4b84f8..8ca823fb3 100644 --- a/pkg/sentry/fs/ramfs/BUILD +++ b/pkg/sentry/fs/ramfs/BUILD @@ -13,14 +13,14 @@ go_library( visibility = ["//pkg/sentry:internal"], deps = [ "//pkg/abi/linux", - "//pkg/sentry/context", + "//pkg/context", "//pkg/sentry/fs", "//pkg/sentry/fs/anon", "//pkg/sentry/fs/fsutil", "//pkg/sentry/socket/unix/transport", - "//pkg/sentry/usermem", "//pkg/sync", "//pkg/syserror", + "//pkg/usermem", "//pkg/waiter", ], ) @@ -31,7 +31,7 @@ go_test( srcs = ["tree_test.go"], library = ":ramfs", deps = [ - "//pkg/sentry/context/contexttest", + "//pkg/sentry/contexttest", "//pkg/sentry/fs", ], ) diff --git a/pkg/sentry/fs/ramfs/dir.go b/pkg/sentry/fs/ramfs/dir.go index dcbb8eb2e..bfa304552 100644 --- a/pkg/sentry/fs/ramfs/dir.go +++ b/pkg/sentry/fs/ramfs/dir.go @@ -20,7 +20,7 @@ import ( "syscall" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" diff --git a/pkg/sentry/fs/ramfs/socket.go b/pkg/sentry/fs/ramfs/socket.go index a24fe2ea2..29ff004f2 100644 --- a/pkg/sentry/fs/ramfs/socket.go +++ b/pkg/sentry/fs/ramfs/socket.go @@ -16,7 +16,7 @@ package ramfs import ( "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" diff --git a/pkg/sentry/fs/ramfs/symlink.go b/pkg/sentry/fs/ramfs/symlink.go index fcfaa29aa..d988349aa 100644 --- a/pkg/sentry/fs/ramfs/symlink.go +++ b/pkg/sentry/fs/ramfs/symlink.go @@ -16,7 +16,7 @@ package ramfs import ( "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/waiter" diff --git a/pkg/sentry/fs/ramfs/tree.go b/pkg/sentry/fs/ramfs/tree.go index 702cc4a1e..dfc9d3453 100644 --- a/pkg/sentry/fs/ramfs/tree.go +++ b/pkg/sentry/fs/ramfs/tree.go @@ -19,10 +19,10 @@ import ( "path" "strings" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/anon" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // MakeDirectoryTree constructs a ramfs tree of all directories containing diff --git a/pkg/sentry/fs/ramfs/tree_test.go b/pkg/sentry/fs/ramfs/tree_test.go index 61a7e2900..a6ed8b2c5 100644 --- a/pkg/sentry/fs/ramfs/tree_test.go +++ b/pkg/sentry/fs/ramfs/tree_test.go @@ -17,7 +17,7 @@ package ramfs import ( "testing" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/sentry/fs" ) diff --git a/pkg/sentry/fs/splice.go b/pkg/sentry/fs/splice.go index 389c330a0..791d1526c 100644 --- a/pkg/sentry/fs/splice.go +++ b/pkg/sentry/fs/splice.go @@ -18,7 +18,7 @@ import ( "io" "sync/atomic" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/syserror" ) diff --git a/pkg/sentry/fs/sys/BUILD b/pkg/sentry/fs/sys/BUILD index cc6b3bfbf..f2e8b9932 100644 --- a/pkg/sentry/fs/sys/BUILD +++ b/pkg/sentry/fs/sys/BUILD @@ -13,12 +13,12 @@ go_library( visibility = ["//pkg/sentry:internal"], deps = [ "//pkg/abi/linux", - "//pkg/sentry/context", + "//pkg/context", "//pkg/sentry/device", "//pkg/sentry/fs", "//pkg/sentry/fs/fsutil", "//pkg/sentry/fs/ramfs", "//pkg/sentry/kernel", - "//pkg/sentry/usermem", + "//pkg/usermem", ], ) diff --git a/pkg/sentry/fs/sys/devices.go b/pkg/sentry/fs/sys/devices.go index 4f78ca8d2..b67065956 100644 --- a/pkg/sentry/fs/sys/devices.go +++ b/pkg/sentry/fs/sys/devices.go @@ -18,7 +18,7 @@ import ( "fmt" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/kernel" diff --git a/pkg/sentry/fs/sys/fs.go b/pkg/sentry/fs/sys/fs.go index e60b63e75..fd03a4e38 100644 --- a/pkg/sentry/fs/sys/fs.go +++ b/pkg/sentry/fs/sys/fs.go @@ -15,7 +15,7 @@ package sys import ( - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" ) diff --git a/pkg/sentry/fs/sys/sys.go b/pkg/sentry/fs/sys/sys.go index b14bf3f55..0891645e4 100644 --- a/pkg/sentry/fs/sys/sys.go +++ b/pkg/sentry/fs/sys/sys.go @@ -16,10 +16,10 @@ package sys import ( - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/ramfs" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) func newFile(ctx context.Context, node fs.InodeOperations, msrc *fs.MountSource) *fs.Inode { diff --git a/pkg/sentry/fs/timerfd/BUILD b/pkg/sentry/fs/timerfd/BUILD index 092668e8d..d16cdb4df 100644 --- a/pkg/sentry/fs/timerfd/BUILD +++ b/pkg/sentry/fs/timerfd/BUILD @@ -7,13 +7,13 @@ go_library( srcs = ["timerfd.go"], visibility = ["//pkg/sentry:internal"], deps = [ - "//pkg/sentry/context", + "//pkg/context", "//pkg/sentry/fs", "//pkg/sentry/fs/anon", "//pkg/sentry/fs/fsutil", "//pkg/sentry/kernel/time", - "//pkg/sentry/usermem", "//pkg/syserror", + "//pkg/usermem", "//pkg/waiter", ], ) diff --git a/pkg/sentry/fs/timerfd/timerfd.go b/pkg/sentry/fs/timerfd/timerfd.go index f8bf663bb..88c344089 100644 --- a/pkg/sentry/fs/timerfd/timerfd.go +++ b/pkg/sentry/fs/timerfd/timerfd.go @@ -19,13 +19,13 @@ package timerfd import ( "sync/atomic" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/anon" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/fs/tmpfs/BUILD b/pkg/sentry/fs/tmpfs/BUILD index 04776555f..aa7199014 100644 --- a/pkg/sentry/fs/tmpfs/BUILD +++ b/pkg/sentry/fs/tmpfs/BUILD @@ -14,8 +14,9 @@ go_library( visibility = ["//pkg/sentry:internal"], deps = [ "//pkg/abi/linux", + "//pkg/context", "//pkg/metric", - "//pkg/sentry/context", + "//pkg/safemem", "//pkg/sentry/device", "//pkg/sentry/fs", "//pkg/sentry/fs/fsutil", @@ -25,12 +26,11 @@ go_library( "//pkg/sentry/kernel/pipe", "//pkg/sentry/kernel/time", "//pkg/sentry/memmap", - "//pkg/sentry/safemem", "//pkg/sentry/socket/unix/transport", "//pkg/sentry/usage", - "//pkg/sentry/usermem", "//pkg/sync", "//pkg/syserror", + "//pkg/usermem", "//pkg/waiter", ], ) @@ -41,10 +41,10 @@ go_test( srcs = ["file_test.go"], library = ":tmpfs", deps = [ - "//pkg/sentry/context", + "//pkg/context", "//pkg/sentry/fs", "//pkg/sentry/kernel/contexttest", "//pkg/sentry/usage", - "//pkg/sentry/usermem", + "//pkg/usermem", ], ) diff --git a/pkg/sentry/fs/tmpfs/file_regular.go b/pkg/sentry/fs/tmpfs/file_regular.go index 9a6943fe4..614f8f8a1 100644 --- a/pkg/sentry/fs/tmpfs/file_regular.go +++ b/pkg/sentry/fs/tmpfs/file_regular.go @@ -15,11 +15,11 @@ package tmpfs import ( - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/memmap" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/fs/tmpfs/file_test.go b/pkg/sentry/fs/tmpfs/file_test.go index 0075ef023..aaba35502 100644 --- a/pkg/sentry/fs/tmpfs/file_test.go +++ b/pkg/sentry/fs/tmpfs/file_test.go @@ -18,11 +18,11 @@ import ( "bytes" "testing" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel/contexttest" "gvisor.dev/gvisor/pkg/sentry/usage" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) func newFileInode(ctx context.Context) *fs.Inode { diff --git a/pkg/sentry/fs/tmpfs/fs.go b/pkg/sentry/fs/tmpfs/fs.go index be98ad751..d5be56c3f 100644 --- a/pkg/sentry/fs/tmpfs/fs.go +++ b/pkg/sentry/fs/tmpfs/fs.go @@ -19,7 +19,7 @@ import ( "strconv" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" ) diff --git a/pkg/sentry/fs/tmpfs/inode_file.go b/pkg/sentry/fs/tmpfs/inode_file.go index f1c87fe41..dabc10662 100644 --- a/pkg/sentry/fs/tmpfs/inode_file.go +++ b/pkg/sentry/fs/tmpfs/inode_file.go @@ -20,18 +20,18 @@ import ( "time" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/metric" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/kernel" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/memmap" - "gvisor.dev/gvisor/pkg/sentry/safemem" "gvisor.dev/gvisor/pkg/sentry/usage" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) var ( diff --git a/pkg/sentry/fs/tmpfs/tmpfs.go b/pkg/sentry/fs/tmpfs/tmpfs.go index 0f718e236..c00cef0a5 100644 --- a/pkg/sentry/fs/tmpfs/tmpfs.go +++ b/pkg/sentry/fs/tmpfs/tmpfs.go @@ -17,7 +17,7 @@ package tmpfs import ( "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/fs/ramfs" @@ -25,8 +25,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel/pipe" "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" "gvisor.dev/gvisor/pkg/sentry/usage" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) var fsInfo = fs.Info{ diff --git a/pkg/sentry/fs/tty/BUILD b/pkg/sentry/fs/tty/BUILD index 29f804c6c..5cb0e0417 100644 --- a/pkg/sentry/fs/tty/BUILD +++ b/pkg/sentry/fs/tty/BUILD @@ -16,20 +16,20 @@ go_library( visibility = ["//pkg/sentry:internal"], deps = [ "//pkg/abi/linux", + "//pkg/context", "//pkg/refs", + "//pkg/safemem", "//pkg/sentry/arch", - "//pkg/sentry/context", "//pkg/sentry/device", "//pkg/sentry/fs", "//pkg/sentry/fs/fsutil", "//pkg/sentry/kernel", "//pkg/sentry/kernel/auth", - "//pkg/sentry/safemem", "//pkg/sentry/socket/unix/transport", "//pkg/sentry/unimpl", - "//pkg/sentry/usermem", "//pkg/sync", "//pkg/syserror", + "//pkg/usermem", "//pkg/waiter", ], ) @@ -41,7 +41,7 @@ go_test( library = ":tty", deps = [ "//pkg/abi/linux", - "//pkg/sentry/context/contexttest", - "//pkg/sentry/usermem", + "//pkg/sentry/contexttest", + "//pkg/usermem", ], ) diff --git a/pkg/sentry/fs/tty/dir.go b/pkg/sentry/fs/tty/dir.go index 88aa66b24..108654827 100644 --- a/pkg/sentry/fs/tty/dir.go +++ b/pkg/sentry/fs/tty/dir.go @@ -21,14 +21,14 @@ import ( "strconv" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/fs/tty/fs.go b/pkg/sentry/fs/tty/fs.go index edee56c12..8fe05ebe5 100644 --- a/pkg/sentry/fs/tty/fs.go +++ b/pkg/sentry/fs/tty/fs.go @@ -15,7 +15,7 @@ package tty import ( - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/device" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/syserror" diff --git a/pkg/sentry/fs/tty/line_discipline.go b/pkg/sentry/fs/tty/line_discipline.go index 9fe02657e..12b1c6097 100644 --- a/pkg/sentry/fs/tty/line_discipline.go +++ b/pkg/sentry/fs/tty/line_discipline.go @@ -19,11 +19,11 @@ import ( "unicode/utf8" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/fs/tty/master.go b/pkg/sentry/fs/tty/master.go index 6b07f6bf2..f62da49bd 100644 --- a/pkg/sentry/fs/tty/master.go +++ b/pkg/sentry/fs/tty/master.go @@ -16,13 +16,13 @@ package tty import ( "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/unimpl" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/fs/tty/queue.go b/pkg/sentry/fs/tty/queue.go index 21ccc6f32..1ca79c0b2 100644 --- a/pkg/sentry/fs/tty/queue.go +++ b/pkg/sentry/fs/tty/queue.go @@ -16,12 +16,12 @@ package tty import ( "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/safemem" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/fs/tty/slave.go b/pkg/sentry/fs/tty/slave.go index 2a51e6bab..db55cdc48 100644 --- a/pkg/sentry/fs/tty/slave.go +++ b/pkg/sentry/fs/tty/slave.go @@ -16,12 +16,12 @@ package tty import ( "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/fs/tty/terminal.go b/pkg/sentry/fs/tty/terminal.go index 917f90cc0..5883f26db 100644 --- a/pkg/sentry/fs/tty/terminal.go +++ b/pkg/sentry/fs/tty/terminal.go @@ -16,11 +16,11 @@ package tty import ( "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/refs" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // Terminal is a pseudoterminal. diff --git a/pkg/sentry/fs/tty/tty_test.go b/pkg/sentry/fs/tty/tty_test.go index 59f07ff8e..2cbc05678 100644 --- a/pkg/sentry/fs/tty/tty_test.go +++ b/pkg/sentry/fs/tty/tty_test.go @@ -18,8 +18,8 @@ import ( "testing" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/sentry/contexttest" + "gvisor.dev/gvisor/pkg/usermem" ) func TestSimpleMasterToSlave(t *testing.T) { diff --git a/pkg/sentry/fsimpl/ext/BUILD b/pkg/sentry/fsimpl/ext/BUILD index a718920d5..6f78f478f 100644 --- a/pkg/sentry/fsimpl/ext/BUILD +++ b/pkg/sentry/fsimpl/ext/BUILD @@ -35,21 +35,21 @@ go_library( deps = [ "//pkg/abi/linux", "//pkg/binary", + "//pkg/context", "//pkg/fd", "//pkg/fspath", "//pkg/log", + "//pkg/safemem", "//pkg/sentry/arch", - "//pkg/sentry/context", "//pkg/sentry/fs", "//pkg/sentry/fsimpl/ext/disklayout", "//pkg/sentry/kernel/auth", "//pkg/sentry/memmap", - "//pkg/sentry/safemem", "//pkg/sentry/syscalls/linux", - "//pkg/sentry/usermem", "//pkg/sentry/vfs", "//pkg/sync", "//pkg/syserror", + "//pkg/usermem", "//pkg/waiter", ], ) @@ -73,14 +73,14 @@ go_test( deps = [ "//pkg/abi/linux", "//pkg/binary", + "//pkg/context", "//pkg/fspath", - "//pkg/sentry/context", - "//pkg/sentry/context/contexttest", + "//pkg/sentry/contexttest", "//pkg/sentry/fsimpl/ext/disklayout", "//pkg/sentry/kernel/auth", - "//pkg/sentry/usermem", "//pkg/sentry/vfs", "//pkg/syserror", + "//pkg/usermem", "//runsc/testutil", "@com_github_google_go-cmp//cmp:go_default_library", "@com_github_google_go-cmp//cmp/cmpopts:go_default_library", diff --git a/pkg/sentry/fsimpl/ext/benchmark/BUILD b/pkg/sentry/fsimpl/ext/benchmark/BUILD index 12f3990c1..6c5a559fd 100644 --- a/pkg/sentry/fsimpl/ext/benchmark/BUILD +++ b/pkg/sentry/fsimpl/ext/benchmark/BUILD @@ -7,9 +7,9 @@ go_test( size = "small", srcs = ["benchmark_test.go"], deps = [ + "//pkg/context", "//pkg/fspath", - "//pkg/sentry/context", - "//pkg/sentry/context/contexttest", + "//pkg/sentry/contexttest", "//pkg/sentry/fsimpl/ext", "//pkg/sentry/kernel/auth", "//pkg/sentry/vfs", diff --git a/pkg/sentry/fsimpl/ext/benchmark/benchmark_test.go b/pkg/sentry/fsimpl/ext/benchmark/benchmark_test.go index a56b03711..d1436b943 100644 --- a/pkg/sentry/fsimpl/ext/benchmark/benchmark_test.go +++ b/pkg/sentry/fsimpl/ext/benchmark/benchmark_test.go @@ -24,9 +24,9 @@ import ( "strings" "testing" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fspath" - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/sentry/fsimpl/ext" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/vfs" diff --git a/pkg/sentry/fsimpl/ext/directory.go b/pkg/sentry/fsimpl/ext/directory.go index 8944171c8..ebb72b75e 100644 --- a/pkg/sentry/fsimpl/ext/directory.go +++ b/pkg/sentry/fsimpl/ext/directory.go @@ -17,8 +17,8 @@ package ext import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/binary" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/log" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fsimpl/ext/disklayout" "gvisor.dev/gvisor/pkg/sentry/memmap" diff --git a/pkg/sentry/fsimpl/ext/ext.go b/pkg/sentry/fsimpl/ext/ext.go index 4b7d17dc6..373d23b74 100644 --- a/pkg/sentry/fsimpl/ext/ext.go +++ b/pkg/sentry/fsimpl/ext/ext.go @@ -21,9 +21,9 @@ import ( "io" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fd" "gvisor.dev/gvisor/pkg/log" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fsimpl/ext/disklayout" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/vfs" diff --git a/pkg/sentry/fsimpl/ext/ext_test.go b/pkg/sentry/fsimpl/ext/ext_test.go index 6c14a1e2d..05f992826 100644 --- a/pkg/sentry/fsimpl/ext/ext_test.go +++ b/pkg/sentry/fsimpl/ext/ext_test.go @@ -25,14 +25,14 @@ import ( "github.com/google/go-cmp/cmp" "github.com/google/go-cmp/cmp/cmpopts" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fspath" - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/sentry/fsimpl/ext/disklayout" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/runsc/testutil" ) diff --git a/pkg/sentry/fsimpl/ext/file_description.go b/pkg/sentry/fsimpl/ext/file_description.go index 841274daf..92f7da40d 100644 --- a/pkg/sentry/fsimpl/ext/file_description.go +++ b/pkg/sentry/fsimpl/ext/file_description.go @@ -16,7 +16,7 @@ package ext import ( "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/syserror" ) diff --git a/pkg/sentry/fsimpl/ext/filesystem.go b/pkg/sentry/fsimpl/ext/filesystem.go index 9afb1a84c..07bf58953 100644 --- a/pkg/sentry/fsimpl/ext/filesystem.go +++ b/pkg/sentry/fsimpl/ext/filesystem.go @@ -19,8 +19,8 @@ import ( "io" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fspath" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fsimpl/ext/disklayout" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/sync" diff --git a/pkg/sentry/fsimpl/ext/regular_file.go b/pkg/sentry/fsimpl/ext/regular_file.go index d11153c90..30135ddb0 100644 --- a/pkg/sentry/fsimpl/ext/regular_file.go +++ b/pkg/sentry/fsimpl/ext/regular_file.go @@ -18,13 +18,13 @@ import ( "io" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/memmap" - "gvisor.dev/gvisor/pkg/sentry/safemem" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // regularFile represents a regular file's inode. This too follows the diff --git a/pkg/sentry/fsimpl/ext/symlink.go b/pkg/sentry/fsimpl/ext/symlink.go index bdf8705c1..1447a4dc1 100644 --- a/pkg/sentry/fsimpl/ext/symlink.go +++ b/pkg/sentry/fsimpl/ext/symlink.go @@ -15,11 +15,11 @@ package ext import ( - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/memmap" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // symlink represents a symlink inode. diff --git a/pkg/sentry/fsimpl/kernfs/BUILD b/pkg/sentry/fsimpl/kernfs/BUILD index 7bf83ccba..e73f1f857 100644 --- a/pkg/sentry/fsimpl/kernfs/BUILD +++ b/pkg/sentry/fsimpl/kernfs/BUILD @@ -29,16 +29,16 @@ go_library( visibility = ["//pkg/sentry:internal"], deps = [ "//pkg/abi/linux", + "//pkg/context", "//pkg/fspath", "//pkg/log", "//pkg/refs", - "//pkg/sentry/context", "//pkg/sentry/kernel/auth", "//pkg/sentry/memmap", - "//pkg/sentry/usermem", "//pkg/sentry/vfs", "//pkg/sync", "//pkg/syserror", + "//pkg/usermem", ], ) @@ -49,13 +49,13 @@ go_test( deps = [ ":kernfs", "//pkg/abi/linux", - "//pkg/sentry/context", - "//pkg/sentry/context/contexttest", + "//pkg/context", + "//pkg/sentry/contexttest", "//pkg/sentry/fsimpl/testutil", "//pkg/sentry/kernel/auth", - "//pkg/sentry/usermem", "//pkg/sentry/vfs", "//pkg/syserror", + "//pkg/usermem", "@com_github_google_go-cmp//cmp:go_default_library", ], ) diff --git a/pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go b/pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go index 75624e0b1..373f801ff 100644 --- a/pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go +++ b/pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go @@ -18,11 +18,11 @@ import ( "fmt" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // DynamicBytesFile implements kernfs.Inode and represents a read-only diff --git a/pkg/sentry/fsimpl/kernfs/fd_impl_util.go b/pkg/sentry/fsimpl/kernfs/fd_impl_util.go index 5fa1fa67b..6104751c8 100644 --- a/pkg/sentry/fsimpl/kernfs/fd_impl_util.go +++ b/pkg/sentry/fsimpl/kernfs/fd_impl_util.go @@ -16,11 +16,11 @@ package kernfs import ( "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/memmap" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // GenericDirectoryFD implements vfs.FileDescriptionImpl for a generic directory diff --git a/pkg/sentry/fsimpl/kernfs/filesystem.go b/pkg/sentry/fsimpl/kernfs/filesystem.go index a4600ad47..9d65d0179 100644 --- a/pkg/sentry/fsimpl/kernfs/filesystem.go +++ b/pkg/sentry/fsimpl/kernfs/filesystem.go @@ -20,8 +20,8 @@ import ( "fmt" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fspath" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/syserror" ) diff --git a/pkg/sentry/fsimpl/kernfs/inode_impl_util.go b/pkg/sentry/fsimpl/kernfs/inode_impl_util.go index 1700fffd9..adca2313f 100644 --- a/pkg/sentry/fsimpl/kernfs/inode_impl_util.go +++ b/pkg/sentry/fsimpl/kernfs/inode_impl_util.go @@ -19,8 +19,8 @@ import ( "sync/atomic" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/refs" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/sync" diff --git a/pkg/sentry/fsimpl/kernfs/kernfs.go b/pkg/sentry/fsimpl/kernfs/kernfs.go index 85bcdcc57..79ebea8a5 100644 --- a/pkg/sentry/fsimpl/kernfs/kernfs.go +++ b/pkg/sentry/fsimpl/kernfs/kernfs.go @@ -56,8 +56,8 @@ import ( "sync/atomic" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/refs" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/sync" diff --git a/pkg/sentry/fsimpl/kernfs/kernfs_test.go b/pkg/sentry/fsimpl/kernfs/kernfs_test.go index fade59491..ee65cf491 100644 --- a/pkg/sentry/fsimpl/kernfs/kernfs_test.go +++ b/pkg/sentry/fsimpl/kernfs/kernfs_test.go @@ -21,14 +21,14 @@ import ( "github.com/google/go-cmp/cmp" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs" "gvisor.dev/gvisor/pkg/sentry/fsimpl/testutil" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) const defaultMode linux.FileMode = 01777 diff --git a/pkg/sentry/fsimpl/kernfs/symlink.go b/pkg/sentry/fsimpl/kernfs/symlink.go index f19f12854..0ee7eb9b7 100644 --- a/pkg/sentry/fsimpl/kernfs/symlink.go +++ b/pkg/sentry/fsimpl/kernfs/symlink.go @@ -16,7 +16,7 @@ package kernfs import ( "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" ) diff --git a/pkg/sentry/fsimpl/proc/BUILD b/pkg/sentry/fsimpl/proc/BUILD index 3768f55b2..12aac2e6a 100644 --- a/pkg/sentry/fsimpl/proc/BUILD +++ b/pkg/sentry/fsimpl/proc/BUILD @@ -16,8 +16,9 @@ go_library( ], deps = [ "//pkg/abi/linux", + "//pkg/context", "//pkg/log", - "//pkg/sentry/context", + "//pkg/safemem", "//pkg/sentry/fs", "//pkg/sentry/fsimpl/kernfs", "//pkg/sentry/inet", @@ -26,15 +27,14 @@ go_library( "//pkg/sentry/kernel/time", "//pkg/sentry/limits", "//pkg/sentry/mm", - "//pkg/sentry/safemem", "//pkg/sentry/socket", "//pkg/sentry/socket/unix", "//pkg/sentry/socket/unix/transport", "//pkg/sentry/usage", - "//pkg/sentry/usermem", "//pkg/sentry/vfs", "//pkg/syserror", "//pkg/tcpip/header", + "//pkg/usermem", ], ) @@ -48,15 +48,15 @@ go_test( library = ":proc", deps = [ "//pkg/abi/linux", + "//pkg/context", "//pkg/fspath", - "//pkg/sentry/context", - "//pkg/sentry/context/contexttest", + "//pkg/sentry/contexttest", "//pkg/sentry/fsimpl/testutil", "//pkg/sentry/inet", "//pkg/sentry/kernel", "//pkg/sentry/kernel/auth", - "//pkg/sentry/usermem", "//pkg/sentry/vfs", "//pkg/syserror", + "//pkg/usermem", ], ) diff --git a/pkg/sentry/fsimpl/proc/filesystem.go b/pkg/sentry/fsimpl/proc/filesystem.go index f49819187..11477b6a9 100644 --- a/pkg/sentry/fsimpl/proc/filesystem.go +++ b/pkg/sentry/fsimpl/proc/filesystem.go @@ -19,7 +19,7 @@ import ( "fmt" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" diff --git a/pkg/sentry/fsimpl/proc/subtasks.go b/pkg/sentry/fsimpl/proc/subtasks.go index 91eded415..353e37195 100644 --- a/pkg/sentry/fsimpl/proc/subtasks.go +++ b/pkg/sentry/fsimpl/proc/subtasks.go @@ -19,7 +19,7 @@ import ( "strconv" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/vfs" diff --git a/pkg/sentry/fsimpl/proc/task.go b/pkg/sentry/fsimpl/proc/task.go index a0580f20d..eb5bc62c0 100644 --- a/pkg/sentry/fsimpl/proc/task.go +++ b/pkg/sentry/fsimpl/proc/task.go @@ -19,7 +19,7 @@ import ( "fmt" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" diff --git a/pkg/sentry/fsimpl/proc/task_files.go b/pkg/sentry/fsimpl/proc/task_files.go index 7bc352ae9..efd3b3453 100644 --- a/pkg/sentry/fsimpl/proc/task_files.go +++ b/pkg/sentry/fsimpl/proc/task_files.go @@ -20,17 +20,17 @@ import ( "io" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/limits" "gvisor.dev/gvisor/pkg/sentry/mm" - "gvisor.dev/gvisor/pkg/sentry/safemem" "gvisor.dev/gvisor/pkg/sentry/usage" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // mm gets the kernel task's MemoryManager. No additional reference is taken on diff --git a/pkg/sentry/fsimpl/proc/tasks.go b/pkg/sentry/fsimpl/proc/tasks.go index 51f634716..e0cb9c47b 100644 --- a/pkg/sentry/fsimpl/proc/tasks.go +++ b/pkg/sentry/fsimpl/proc/tasks.go @@ -20,7 +20,7 @@ import ( "strconv" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" diff --git a/pkg/sentry/fsimpl/proc/tasks_files.go b/pkg/sentry/fsimpl/proc/tasks_files.go index ad3760e39..434998910 100644 --- a/pkg/sentry/fsimpl/proc/tasks_files.go +++ b/pkg/sentry/fsimpl/proc/tasks_files.go @@ -20,14 +20,14 @@ import ( "strconv" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/usage" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) type selfSymlink struct { diff --git a/pkg/sentry/fsimpl/proc/tasks_net.go b/pkg/sentry/fsimpl/proc/tasks_net.go index 4aaf23e97..608fec017 100644 --- a/pkg/sentry/fsimpl/proc/tasks_net.go +++ b/pkg/sentry/fsimpl/proc/tasks_net.go @@ -22,8 +22,8 @@ import ( "time" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/log" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs" "gvisor.dev/gvisor/pkg/sentry/inet" @@ -32,9 +32,9 @@ import ( "gvisor.dev/gvisor/pkg/sentry/socket" "gvisor.dev/gvisor/pkg/sentry/socket/unix" "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/tcpip/header" + "gvisor.dev/gvisor/pkg/usermem" ) func newNetDir(root *auth.Credentials, inoGen InoGenerator, k *kernel.Kernel) *kernfs.Dentry { diff --git a/pkg/sentry/fsimpl/proc/tasks_sys.go b/pkg/sentry/fsimpl/proc/tasks_sys.go index aabf2bf0c..ad963870b 100644 --- a/pkg/sentry/fsimpl/proc/tasks_sys.go +++ b/pkg/sentry/fsimpl/proc/tasks_sys.go @@ -19,7 +19,7 @@ import ( "fmt" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" diff --git a/pkg/sentry/fsimpl/proc/tasks_sys_test.go b/pkg/sentry/fsimpl/proc/tasks_sys_test.go index 0a1d3f34b..be54897bb 100644 --- a/pkg/sentry/fsimpl/proc/tasks_sys_test.go +++ b/pkg/sentry/fsimpl/proc/tasks_sys_test.go @@ -20,7 +20,7 @@ import ( "testing" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/sentry/inet" ) diff --git a/pkg/sentry/fsimpl/proc/tasks_test.go b/pkg/sentry/fsimpl/proc/tasks_test.go index 2c1635f33..6fc3524db 100644 --- a/pkg/sentry/fsimpl/proc/tasks_test.go +++ b/pkg/sentry/fsimpl/proc/tasks_test.go @@ -22,14 +22,14 @@ import ( "testing" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fspath" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fsimpl/testutil" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) var ( diff --git a/pkg/sentry/fsimpl/sys/BUILD b/pkg/sentry/fsimpl/sys/BUILD index beda141f1..66c0d8bc8 100644 --- a/pkg/sentry/fsimpl/sys/BUILD +++ b/pkg/sentry/fsimpl/sys/BUILD @@ -9,7 +9,7 @@ go_library( ], deps = [ "//pkg/abi/linux", - "//pkg/sentry/context", + "//pkg/context", "//pkg/sentry/fsimpl/kernfs", "//pkg/sentry/kernel", "//pkg/sentry/kernel/auth", diff --git a/pkg/sentry/fsimpl/sys/sys.go b/pkg/sentry/fsimpl/sys/sys.go index 1305ad01d..e35d52d17 100644 --- a/pkg/sentry/fsimpl/sys/sys.go +++ b/pkg/sentry/fsimpl/sys/sys.go @@ -20,7 +20,7 @@ import ( "fmt" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" diff --git a/pkg/sentry/fsimpl/testutil/BUILD b/pkg/sentry/fsimpl/testutil/BUILD index 12053a5b6..efd5974c4 100644 --- a/pkg/sentry/fsimpl/testutil/BUILD +++ b/pkg/sentry/fsimpl/testutil/BUILD @@ -12,10 +12,10 @@ go_library( visibility = ["//pkg/sentry:internal"], deps = [ "//pkg/abi/linux", + "//pkg/context", "//pkg/cpuid", "//pkg/fspath", "//pkg/memutil", - "//pkg/sentry/context", "//pkg/sentry/fs", "//pkg/sentry/kernel", "//pkg/sentry/kernel/auth", @@ -27,9 +27,9 @@ go_library( "//pkg/sentry/platform/kvm", "//pkg/sentry/platform/ptrace", "//pkg/sentry/time", - "//pkg/sentry/usermem", "//pkg/sentry/vfs", "//pkg/sync", + "//pkg/usermem", "@com_github_google_go-cmp//cmp:go_default_library", ], ) diff --git a/pkg/sentry/fsimpl/testutil/kernel.go b/pkg/sentry/fsimpl/testutil/kernel.go index 295da2d52..89f8c4915 100644 --- a/pkg/sentry/fsimpl/testutil/kernel.go +++ b/pkg/sentry/fsimpl/testutil/kernel.go @@ -21,9 +21,9 @@ import ( "runtime" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/cpuid" "gvisor.dev/gvisor/pkg/memutil" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" diff --git a/pkg/sentry/fsimpl/testutil/testutil.go b/pkg/sentry/fsimpl/testutil/testutil.go index 2a723a89f..1c98335c1 100644 --- a/pkg/sentry/fsimpl/testutil/testutil.go +++ b/pkg/sentry/fsimpl/testutil/testutil.go @@ -24,12 +24,12 @@ import ( "github.com/google/go-cmp/cmp" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fspath" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/sync" + "gvisor.dev/gvisor/pkg/usermem" ) // System represents the context for a single test. diff --git a/pkg/sentry/fsimpl/tmpfs/BUILD b/pkg/sentry/fsimpl/tmpfs/BUILD index 857e98bc5..fb436860c 100644 --- a/pkg/sentry/fsimpl/tmpfs/BUILD +++ b/pkg/sentry/fsimpl/tmpfs/BUILD @@ -30,10 +30,11 @@ go_library( deps = [ "//pkg/abi/linux", "//pkg/amutex", + "//pkg/context", "//pkg/fspath", "//pkg/log", + "//pkg/safemem", "//pkg/sentry/arch", - "//pkg/sentry/context", "//pkg/sentry/fs", "//pkg/sentry/fs/fsutil", "//pkg/sentry/kernel", @@ -43,12 +44,11 @@ go_library( "//pkg/sentry/memmap", "//pkg/sentry/pgalloc", "//pkg/sentry/platform", - "//pkg/sentry/safemem", "//pkg/sentry/usage", - "//pkg/sentry/usermem", "//pkg/sentry/vfs", "//pkg/sync", "//pkg/syserror", + "//pkg/usermem", ], ) @@ -59,10 +59,10 @@ go_test( deps = [ ":tmpfs", "//pkg/abi/linux", + "//pkg/context", "//pkg/fspath", "//pkg/refs", - "//pkg/sentry/context", - "//pkg/sentry/context/contexttest", + "//pkg/sentry/contexttest", "//pkg/sentry/fs", "//pkg/sentry/fs/tmpfs", "//pkg/sentry/kernel/auth", @@ -82,13 +82,13 @@ go_test( library = ":tmpfs", deps = [ "//pkg/abi/linux", + "//pkg/context", "//pkg/fspath", - "//pkg/sentry/context", - "//pkg/sentry/context/contexttest", + "//pkg/sentry/contexttest", "//pkg/sentry/kernel/auth", "//pkg/sentry/kernel/contexttest", - "//pkg/sentry/usermem", "//pkg/sentry/vfs", "//pkg/syserror", + "//pkg/usermem", ], ) diff --git a/pkg/sentry/fsimpl/tmpfs/benchmark_test.go b/pkg/sentry/fsimpl/tmpfs/benchmark_test.go index d88c83499..54241c8e8 100644 --- a/pkg/sentry/fsimpl/tmpfs/benchmark_test.go +++ b/pkg/sentry/fsimpl/tmpfs/benchmark_test.go @@ -21,10 +21,10 @@ import ( "testing" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fspath" "gvisor.dev/gvisor/pkg/refs" - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/sentry/fs" _ "gvisor.dev/gvisor/pkg/sentry/fs/tmpfs" "gvisor.dev/gvisor/pkg/sentry/fsimpl/tmpfs" diff --git a/pkg/sentry/fsimpl/tmpfs/directory.go b/pkg/sentry/fsimpl/tmpfs/directory.go index 887ca2619..dc0d27cf9 100644 --- a/pkg/sentry/fsimpl/tmpfs/directory.go +++ b/pkg/sentry/fsimpl/tmpfs/directory.go @@ -16,7 +16,7 @@ package tmpfs import ( "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/syserror" diff --git a/pkg/sentry/fsimpl/tmpfs/filesystem.go b/pkg/sentry/fsimpl/tmpfs/filesystem.go index d726f03c5..5ee9cf1e9 100644 --- a/pkg/sentry/fsimpl/tmpfs/filesystem.go +++ b/pkg/sentry/fsimpl/tmpfs/filesystem.go @@ -19,8 +19,8 @@ import ( "sync/atomic" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fspath" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/syserror" ) diff --git a/pkg/sentry/fsimpl/tmpfs/named_pipe.go b/pkg/sentry/fsimpl/tmpfs/named_pipe.go index 482aabd52..0c57fdca3 100644 --- a/pkg/sentry/fsimpl/tmpfs/named_pipe.go +++ b/pkg/sentry/fsimpl/tmpfs/named_pipe.go @@ -16,11 +16,11 @@ package tmpfs import ( "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/kernel/pipe" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/usermem" ) type namedPipe struct { diff --git a/pkg/sentry/fsimpl/tmpfs/pipe_test.go b/pkg/sentry/fsimpl/tmpfs/pipe_test.go index 70b42a6ec..5ee7f2a72 100644 --- a/pkg/sentry/fsimpl/tmpfs/pipe_test.go +++ b/pkg/sentry/fsimpl/tmpfs/pipe_test.go @@ -19,13 +19,13 @@ import ( "testing" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fspath" - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) const fileName = "mypipe" diff --git a/pkg/sentry/fsimpl/tmpfs/regular_file.go b/pkg/sentry/fsimpl/tmpfs/regular_file.go index 7c633c1b0..e9e6faf67 100644 --- a/pkg/sentry/fsimpl/tmpfs/regular_file.go +++ b/pkg/sentry/fsimpl/tmpfs/regular_file.go @@ -20,17 +20,17 @@ import ( "sync/atomic" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/pgalloc" - "gvisor.dev/gvisor/pkg/sentry/safemem" "gvisor.dev/gvisor/pkg/sentry/usage" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) type regularFile struct { diff --git a/pkg/sentry/fsimpl/tmpfs/regular_file_test.go b/pkg/sentry/fsimpl/tmpfs/regular_file_test.go index 034a29fdb..32552e261 100644 --- a/pkg/sentry/fsimpl/tmpfs/regular_file_test.go +++ b/pkg/sentry/fsimpl/tmpfs/regular_file_test.go @@ -22,12 +22,12 @@ import ( "testing" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fspath" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/kernel/contexttest" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/usermem" ) // nextFileID is used to generate unique file names. diff --git a/pkg/sentry/fsimpl/tmpfs/tmpfs.go b/pkg/sentry/fsimpl/tmpfs/tmpfs.go index 515f033f2..88dbd6e35 100644 --- a/pkg/sentry/fsimpl/tmpfs/tmpfs.go +++ b/pkg/sentry/fsimpl/tmpfs/tmpfs.go @@ -29,7 +29,7 @@ import ( "sync/atomic" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/pgalloc" diff --git a/pkg/sentry/hostmm/BUILD b/pkg/sentry/hostmm/BUILD index a145a5ca3..61c78569d 100644 --- a/pkg/sentry/hostmm/BUILD +++ b/pkg/sentry/hostmm/BUILD @@ -12,6 +12,6 @@ go_library( deps = [ "//pkg/fd", "//pkg/log", - "//pkg/sentry/usermem", + "//pkg/usermem", ], ) diff --git a/pkg/sentry/hostmm/hostmm.go b/pkg/sentry/hostmm/hostmm.go index 19335ca73..506c7864a 100644 --- a/pkg/sentry/hostmm/hostmm.go +++ b/pkg/sentry/hostmm/hostmm.go @@ -24,7 +24,7 @@ import ( "gvisor.dev/gvisor/pkg/fd" "gvisor.dev/gvisor/pkg/log" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // NotifyCurrentMemcgPressureCallback requests that f is called whenever the diff --git a/pkg/sentry/inet/BUILD b/pkg/sentry/inet/BUILD index aa621b724..334432abf 100644 --- a/pkg/sentry/inet/BUILD +++ b/pkg/sentry/inet/BUILD @@ -13,7 +13,7 @@ go_library( "test_stack.go", ], deps = [ - "//pkg/sentry/context", + "//pkg/context", "//pkg/tcpip/stack", ], ) diff --git a/pkg/sentry/inet/context.go b/pkg/sentry/inet/context.go index 4eda7dd1f..e8cc1bffd 100644 --- a/pkg/sentry/inet/context.go +++ b/pkg/sentry/inet/context.go @@ -15,7 +15,7 @@ package inet import ( - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" ) // contextID is the inet package's type for context.Context.Value keys. diff --git a/pkg/sentry/kernel/BUILD b/pkg/sentry/kernel/BUILD index cebaccd92..0738946d9 100644 --- a/pkg/sentry/kernel/BUILD +++ b/pkg/sentry/kernel/BUILD @@ -153,14 +153,15 @@ go_library( "//pkg/binary", "//pkg/bits", "//pkg/bpf", + "//pkg/context", "//pkg/cpuid", "//pkg/eventchannel", "//pkg/log", "//pkg/metric", "//pkg/refs", + "//pkg/safemem", "//pkg/secio", "//pkg/sentry/arch", - "//pkg/sentry/context", "//pkg/sentry/device", "//pkg/sentry/fs", "//pkg/sentry/fs/lock", @@ -180,7 +181,6 @@ go_library( "//pkg/sentry/mm", "//pkg/sentry/pgalloc", "//pkg/sentry/platform", - "//pkg/sentry/safemem", "//pkg/sentry/socket/netlink/port", "//pkg/sentry/socket/unix/transport", "//pkg/sentry/time", @@ -188,7 +188,6 @@ go_library( "//pkg/sentry/unimpl:unimplemented_syscall_go_proto", "//pkg/sentry/uniqueid", "//pkg/sentry/usage", - "//pkg/sentry/usermem", "//pkg/state", "//pkg/state/statefile", "//pkg/sync", @@ -196,6 +195,7 @@ go_library( "//pkg/syserror", "//pkg/tcpip", "//pkg/tcpip/stack", + "//pkg/usermem", "//pkg/waiter", ], ) @@ -212,9 +212,9 @@ go_test( library = ":kernel", deps = [ "//pkg/abi", + "//pkg/context", "//pkg/sentry/arch", - "//pkg/sentry/context", - "//pkg/sentry/context/contexttest", + "//pkg/sentry/contexttest", "//pkg/sentry/fs", "//pkg/sentry/fs/filetest", "//pkg/sentry/kernel/sched", @@ -222,8 +222,8 @@ go_test( "//pkg/sentry/pgalloc", "//pkg/sentry/time", "//pkg/sentry/usage", - "//pkg/sentry/usermem", "//pkg/sync", "//pkg/syserror", + "//pkg/usermem", ], ) diff --git a/pkg/sentry/kernel/auth/BUILD b/pkg/sentry/kernel/auth/BUILD index 64537c9be..2bc49483a 100644 --- a/pkg/sentry/kernel/auth/BUILD +++ b/pkg/sentry/kernel/auth/BUILD @@ -61,8 +61,8 @@ go_library( deps = [ "//pkg/abi/linux", "//pkg/bits", + "//pkg/context", "//pkg/log", - "//pkg/sentry/context", "//pkg/sync", "//pkg/syserror", ], diff --git a/pkg/sentry/kernel/auth/context.go b/pkg/sentry/kernel/auth/context.go index 5c0e7d6b6..ef5723127 100644 --- a/pkg/sentry/kernel/auth/context.go +++ b/pkg/sentry/kernel/auth/context.go @@ -15,7 +15,7 @@ package auth import ( - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" ) // contextID is the auth package's type for context.Context.Value keys. diff --git a/pkg/sentry/kernel/auth/id_map.go b/pkg/sentry/kernel/auth/id_map.go index 3d74bc610..28cbe159d 100644 --- a/pkg/sentry/kernel/auth/id_map.go +++ b/pkg/sentry/kernel/auth/id_map.go @@ -16,7 +16,7 @@ package auth import ( "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/syserror" ) diff --git a/pkg/sentry/kernel/context.go b/pkg/sentry/kernel/context.go index 3c9dceaba..0c40bf315 100644 --- a/pkg/sentry/kernel/context.go +++ b/pkg/sentry/kernel/context.go @@ -17,8 +17,8 @@ package kernel import ( "time" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/log" - "gvisor.dev/gvisor/pkg/sentry/context" ) // contextID is the kernel package's type for context.Context.Value keys. diff --git a/pkg/sentry/kernel/contexttest/BUILD b/pkg/sentry/kernel/contexttest/BUILD index daff608d7..9d26392c0 100644 --- a/pkg/sentry/kernel/contexttest/BUILD +++ b/pkg/sentry/kernel/contexttest/BUILD @@ -8,8 +8,8 @@ go_library( srcs = ["contexttest.go"], visibility = ["//pkg/sentry:internal"], deps = [ - "//pkg/sentry/context", - "//pkg/sentry/context/contexttest", + "//pkg/context", + "//pkg/sentry/contexttest", "//pkg/sentry/kernel", "//pkg/sentry/pgalloc", "//pkg/sentry/platform", diff --git a/pkg/sentry/kernel/contexttest/contexttest.go b/pkg/sentry/kernel/contexttest/contexttest.go index 82f9d8922..22c340e56 100644 --- a/pkg/sentry/kernel/contexttest/contexttest.go +++ b/pkg/sentry/kernel/contexttest/contexttest.go @@ -19,8 +19,8 @@ package contexttest import ( "testing" - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/pgalloc" "gvisor.dev/gvisor/pkg/sentry/platform" diff --git a/pkg/sentry/kernel/epoll/BUILD b/pkg/sentry/kernel/epoll/BUILD index 19e16ab3a..dedf0fa15 100644 --- a/pkg/sentry/kernel/epoll/BUILD +++ b/pkg/sentry/kernel/epoll/BUILD @@ -24,13 +24,13 @@ go_library( ], visibility = ["//pkg/sentry:internal"], deps = [ + "//pkg/context", "//pkg/refs", - "//pkg/sentry/context", "//pkg/sentry/fs", "//pkg/sentry/fs/anon", "//pkg/sentry/fs/fsutil", - "//pkg/sentry/usermem", "//pkg/sync", + "//pkg/usermem", "//pkg/waiter", ], ) @@ -43,7 +43,7 @@ go_test( ], library = ":epoll", deps = [ - "//pkg/sentry/context/contexttest", + "//pkg/sentry/contexttest", "//pkg/sentry/fs/filetest", "//pkg/waiter", ], diff --git a/pkg/sentry/kernel/epoll/epoll.go b/pkg/sentry/kernel/epoll/epoll.go index e84742993..8bffb78fc 100644 --- a/pkg/sentry/kernel/epoll/epoll.go +++ b/pkg/sentry/kernel/epoll/epoll.go @@ -20,13 +20,13 @@ import ( "fmt" "syscall" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/refs" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/anon" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/kernel/epoll/epoll_test.go b/pkg/sentry/kernel/epoll/epoll_test.go index 4a20d4c82..22630e9c5 100644 --- a/pkg/sentry/kernel/epoll/epoll_test.go +++ b/pkg/sentry/kernel/epoll/epoll_test.go @@ -17,7 +17,7 @@ package epoll import ( "testing" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/sentry/fs/filetest" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/kernel/eventfd/BUILD b/pkg/sentry/kernel/eventfd/BUILD index ee2d74864..9983a32e5 100644 --- a/pkg/sentry/kernel/eventfd/BUILD +++ b/pkg/sentry/kernel/eventfd/BUILD @@ -8,14 +8,14 @@ go_library( visibility = ["//pkg/sentry:internal"], deps = [ "//pkg/abi/linux", + "//pkg/context", "//pkg/fdnotifier", - "//pkg/sentry/context", "//pkg/sentry/fs", "//pkg/sentry/fs/anon", "//pkg/sentry/fs/fsutil", - "//pkg/sentry/usermem", "//pkg/sync", "//pkg/syserror", + "//pkg/usermem", "//pkg/waiter", ], ) @@ -26,8 +26,8 @@ go_test( srcs = ["eventfd_test.go"], library = ":eventfd", deps = [ - "//pkg/sentry/context/contexttest", - "//pkg/sentry/usermem", + "//pkg/sentry/contexttest", + "//pkg/usermem", "//pkg/waiter", ], ) diff --git a/pkg/sentry/kernel/eventfd/eventfd.go b/pkg/sentry/kernel/eventfd/eventfd.go index 687690679..87951adeb 100644 --- a/pkg/sentry/kernel/eventfd/eventfd.go +++ b/pkg/sentry/kernel/eventfd/eventfd.go @@ -21,14 +21,14 @@ import ( "syscall" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fdnotifier" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/anon" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/kernel/eventfd/eventfd_test.go b/pkg/sentry/kernel/eventfd/eventfd_test.go index 018c7f3ef..9b4892f74 100644 --- a/pkg/sentry/kernel/eventfd/eventfd_test.go +++ b/pkg/sentry/kernel/eventfd/eventfd_test.go @@ -17,8 +17,8 @@ package eventfd import ( "testing" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/sentry/contexttest" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/kernel/fd_table.go b/pkg/sentry/kernel/fd_table.go index 0ad4135b3..9460bb235 100644 --- a/pkg/sentry/kernel/fd_table.go +++ b/pkg/sentry/kernel/fd_table.go @@ -22,8 +22,8 @@ import ( "syscall" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/refs" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/lock" "gvisor.dev/gvisor/pkg/sentry/limits" diff --git a/pkg/sentry/kernel/fd_table_test.go b/pkg/sentry/kernel/fd_table_test.go index 86164df49..261b815f2 100644 --- a/pkg/sentry/kernel/fd_table_test.go +++ b/pkg/sentry/kernel/fd_table_test.go @@ -18,8 +18,8 @@ import ( "runtime" "testing" - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/filetest" "gvisor.dev/gvisor/pkg/sentry/limits" diff --git a/pkg/sentry/kernel/futex/BUILD b/pkg/sentry/kernel/futex/BUILD index f413d8ae2..c5021f2db 100644 --- a/pkg/sentry/kernel/futex/BUILD +++ b/pkg/sentry/kernel/futex/BUILD @@ -36,12 +36,12 @@ go_library( visibility = ["//pkg/sentry:internal"], deps = [ "//pkg/abi/linux", + "//pkg/context", "//pkg/log", - "//pkg/sentry/context", "//pkg/sentry/memmap", - "//pkg/sentry/usermem", "//pkg/sync", "//pkg/syserror", + "//pkg/usermem", ], ) @@ -51,7 +51,7 @@ go_test( srcs = ["futex_test.go"], library = ":futex", deps = [ - "//pkg/sentry/usermem", "//pkg/sync", + "//pkg/usermem", ], ) diff --git a/pkg/sentry/kernel/futex/futex.go b/pkg/sentry/kernel/futex/futex.go index d1931c8f4..732e66da4 100644 --- a/pkg/sentry/kernel/futex/futex.go +++ b/pkg/sentry/kernel/futex/futex.go @@ -20,9 +20,9 @@ package futex import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/sentry/memmap" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // KeyKind indicates the type of a Key. diff --git a/pkg/sentry/kernel/futex/futex_test.go b/pkg/sentry/kernel/futex/futex_test.go index c23126ca5..7c5c7665b 100644 --- a/pkg/sentry/kernel/futex/futex_test.go +++ b/pkg/sentry/kernel/futex/futex_test.go @@ -22,8 +22,8 @@ import ( "testing" "unsafe" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" + "gvisor.dev/gvisor/pkg/usermem" ) // testData implements the Target interface, and allows us to diff --git a/pkg/sentry/kernel/kernel.go b/pkg/sentry/kernel/kernel.go index c85e97fef..7b90fac5a 100644 --- a/pkg/sentry/kernel/kernel.go +++ b/pkg/sentry/kernel/kernel.go @@ -40,12 +40,12 @@ import ( "time" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/cpuid" "gvisor.dev/gvisor/pkg/eventchannel" "gvisor.dev/gvisor/pkg/log" "gvisor.dev/gvisor/pkg/refs" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/timerfd" "gvisor.dev/gvisor/pkg/sentry/hostcpu" diff --git a/pkg/sentry/kernel/pipe/BUILD b/pkg/sentry/kernel/pipe/BUILD index 2c7b6206f..4c049d5b4 100644 --- a/pkg/sentry/kernel/pipe/BUILD +++ b/pkg/sentry/kernel/pipe/BUILD @@ -33,16 +33,16 @@ go_library( deps = [ "//pkg/abi/linux", "//pkg/amutex", + "//pkg/context", + "//pkg/safemem", "//pkg/sentry/arch", - "//pkg/sentry/context", "//pkg/sentry/device", "//pkg/sentry/fs", "//pkg/sentry/fs/fsutil", - "//pkg/sentry/safemem", - "//pkg/sentry/usermem", "//pkg/sentry/vfs", "//pkg/sync", "//pkg/syserror", + "//pkg/usermem", "//pkg/waiter", ], ) @@ -57,11 +57,11 @@ go_test( ], library = ":pipe", deps = [ - "//pkg/sentry/context", - "//pkg/sentry/context/contexttest", + "//pkg/context", + "//pkg/sentry/contexttest", "//pkg/sentry/fs", - "//pkg/sentry/usermem", "//pkg/syserror", + "//pkg/usermem", "//pkg/waiter", ], ) diff --git a/pkg/sentry/kernel/pipe/buffer.go b/pkg/sentry/kernel/pipe/buffer.go index 1c0f34269..fe3be5dbd 100644 --- a/pkg/sentry/kernel/pipe/buffer.go +++ b/pkg/sentry/kernel/pipe/buffer.go @@ -17,7 +17,7 @@ package pipe import ( "io" - "gvisor.dev/gvisor/pkg/sentry/safemem" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sync" ) diff --git a/pkg/sentry/kernel/pipe/buffer_test.go b/pkg/sentry/kernel/pipe/buffer_test.go index ee1b90115..4d54b8b8f 100644 --- a/pkg/sentry/kernel/pipe/buffer_test.go +++ b/pkg/sentry/kernel/pipe/buffer_test.go @@ -18,7 +18,7 @@ import ( "testing" "unsafe" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) func TestBufferSize(t *testing.T) { diff --git a/pkg/sentry/kernel/pipe/node.go b/pkg/sentry/kernel/pipe/node.go index 716f589af..4b688c627 100644 --- a/pkg/sentry/kernel/pipe/node.go +++ b/pkg/sentry/kernel/pipe/node.go @@ -16,7 +16,7 @@ package pipe import ( "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sync" diff --git a/pkg/sentry/kernel/pipe/node_test.go b/pkg/sentry/kernel/pipe/node_test.go index 16fa80abe..ab75a87ff 100644 --- a/pkg/sentry/kernel/pipe/node_test.go +++ b/pkg/sentry/kernel/pipe/node_test.go @@ -18,11 +18,11 @@ import ( "testing" "time" - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/sentry/fs" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) type sleeper struct { diff --git a/pkg/sentry/kernel/pipe/pipe.go b/pkg/sentry/kernel/pipe/pipe.go index e4fd7d420..08410283f 100644 --- a/pkg/sentry/kernel/pipe/pipe.go +++ b/pkg/sentry/kernel/pipe/pipe.go @@ -20,7 +20,7 @@ import ( "sync/atomic" "syscall" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" diff --git a/pkg/sentry/kernel/pipe/pipe_test.go b/pkg/sentry/kernel/pipe/pipe_test.go index e3a14b665..bda739dbe 100644 --- a/pkg/sentry/kernel/pipe/pipe_test.go +++ b/pkg/sentry/kernel/pipe/pipe_test.go @@ -18,9 +18,9 @@ import ( "bytes" "testing" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/kernel/pipe/pipe_util.go b/pkg/sentry/kernel/pipe/pipe_util.go index 8394eb78b..80158239e 100644 --- a/pkg/sentry/kernel/pipe/pipe_util.go +++ b/pkg/sentry/kernel/pipe/pipe_util.go @@ -21,10 +21,10 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/amutex" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/kernel/pipe/reader_writer.go b/pkg/sentry/kernel/pipe/reader_writer.go index b4d29fc77..b2b5691ee 100644 --- a/pkg/sentry/kernel/pipe/reader_writer.go +++ b/pkg/sentry/kernel/pipe/reader_writer.go @@ -17,11 +17,11 @@ package pipe import ( "io" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // ReaderWriter satisfies the FileOperations interface and services both diff --git a/pkg/sentry/kernel/pipe/vfs.go b/pkg/sentry/kernel/pipe/vfs.go index 6f83e3cee..a5675bd70 100644 --- a/pkg/sentry/kernel/pipe/vfs.go +++ b/pkg/sentry/kernel/pipe/vfs.go @@ -16,12 +16,12 @@ package pipe import ( "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/kernel/ptrace.go b/pkg/sentry/kernel/ptrace.go index 3be171cdc..35ad97d5d 100644 --- a/pkg/sentry/kernel/ptrace.go +++ b/pkg/sentry/kernel/ptrace.go @@ -20,8 +20,8 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/mm" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // ptraceOptions are the subset of options controlling a task's ptrace behavior diff --git a/pkg/sentry/kernel/ptrace_amd64.go b/pkg/sentry/kernel/ptrace_amd64.go index 5514cf432..cef1276ec 100644 --- a/pkg/sentry/kernel/ptrace_amd64.go +++ b/pkg/sentry/kernel/ptrace_amd64.go @@ -18,8 +18,8 @@ package kernel import ( "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // ptraceArch implements arch-specific ptrace commands. diff --git a/pkg/sentry/kernel/ptrace_arm64.go b/pkg/sentry/kernel/ptrace_arm64.go index 61e412911..d971b96b3 100644 --- a/pkg/sentry/kernel/ptrace_arm64.go +++ b/pkg/sentry/kernel/ptrace_arm64.go @@ -17,8 +17,8 @@ package kernel import ( - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // ptraceArch implements arch-specific ptrace commands. diff --git a/pkg/sentry/kernel/rseq.go b/pkg/sentry/kernel/rseq.go index b14429854..efebfd872 100644 --- a/pkg/sentry/kernel/rseq.go +++ b/pkg/sentry/kernel/rseq.go @@ -19,8 +19,8 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/sentry/hostcpu" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // Restartable sequences. diff --git a/pkg/sentry/kernel/seccomp.go b/pkg/sentry/kernel/seccomp.go index 2347dcf36..c38c5a40c 100644 --- a/pkg/sentry/kernel/seccomp.go +++ b/pkg/sentry/kernel/seccomp.go @@ -21,8 +21,8 @@ import ( "gvisor.dev/gvisor/pkg/binary" "gvisor.dev/gvisor/pkg/bpf" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) const maxSyscallFilterInstructions = 1 << 15 diff --git a/pkg/sentry/kernel/semaphore/BUILD b/pkg/sentry/kernel/semaphore/BUILD index 76e19b551..65e5427c1 100644 --- a/pkg/sentry/kernel/semaphore/BUILD +++ b/pkg/sentry/kernel/semaphore/BUILD @@ -24,8 +24,8 @@ go_library( visibility = ["//pkg/sentry:internal"], deps = [ "//pkg/abi/linux", + "//pkg/context", "//pkg/log", - "//pkg/sentry/context", "//pkg/sentry/fs", "//pkg/sentry/kernel/auth", "//pkg/sentry/kernel/time", @@ -41,8 +41,8 @@ go_test( library = ":semaphore", deps = [ "//pkg/abi/linux", - "//pkg/sentry/context", - "//pkg/sentry/context/contexttest", + "//pkg/context", + "//pkg/sentry/contexttest", "//pkg/sentry/kernel/auth", "//pkg/syserror", ], diff --git a/pkg/sentry/kernel/semaphore/semaphore.go b/pkg/sentry/kernel/semaphore/semaphore.go index 18299814e..1000f3287 100644 --- a/pkg/sentry/kernel/semaphore/semaphore.go +++ b/pkg/sentry/kernel/semaphore/semaphore.go @@ -19,8 +19,8 @@ import ( "fmt" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/log" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" diff --git a/pkg/sentry/kernel/semaphore/semaphore_test.go b/pkg/sentry/kernel/semaphore/semaphore_test.go index c235f6ca4..e47acefdf 100644 --- a/pkg/sentry/kernel/semaphore/semaphore_test.go +++ b/pkg/sentry/kernel/semaphore/semaphore_test.go @@ -18,8 +18,8 @@ import ( "testing" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/syserror" ) diff --git a/pkg/sentry/kernel/shm/BUILD b/pkg/sentry/kernel/shm/BUILD index 5547c5abf..bfd779837 100644 --- a/pkg/sentry/kernel/shm/BUILD +++ b/pkg/sentry/kernel/shm/BUILD @@ -11,9 +11,9 @@ go_library( visibility = ["//pkg/sentry:internal"], deps = [ "//pkg/abi/linux", + "//pkg/context", "//pkg/log", "//pkg/refs", - "//pkg/sentry/context", "//pkg/sentry/device", "//pkg/sentry/fs", "//pkg/sentry/kernel/auth", @@ -22,8 +22,8 @@ go_library( "//pkg/sentry/pgalloc", "//pkg/sentry/platform", "//pkg/sentry/usage", - "//pkg/sentry/usermem", "//pkg/sync", "//pkg/syserror", + "//pkg/usermem", ], ) diff --git a/pkg/sentry/kernel/shm/shm.go b/pkg/sentry/kernel/shm/shm.go index 8ddef7eb8..208569057 100644 --- a/pkg/sentry/kernel/shm/shm.go +++ b/pkg/sentry/kernel/shm/shm.go @@ -37,9 +37,9 @@ import ( "fmt" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/log" "gvisor.dev/gvisor/pkg/refs" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" @@ -47,9 +47,9 @@ import ( "gvisor.dev/gvisor/pkg/sentry/pgalloc" "gvisor.dev/gvisor/pkg/sentry/platform" "gvisor.dev/gvisor/pkg/sentry/usage" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // Key represents a shm segment key. Analogous to a file name. diff --git a/pkg/sentry/kernel/signalfd/BUILD b/pkg/sentry/kernel/signalfd/BUILD index 5d44773d4..3eb78e91b 100644 --- a/pkg/sentry/kernel/signalfd/BUILD +++ b/pkg/sentry/kernel/signalfd/BUILD @@ -9,14 +9,14 @@ go_library( deps = [ "//pkg/abi/linux", "//pkg/binary", - "//pkg/sentry/context", + "//pkg/context", "//pkg/sentry/fs", "//pkg/sentry/fs/anon", "//pkg/sentry/fs/fsutil", "//pkg/sentry/kernel", - "//pkg/sentry/usermem", "//pkg/sync", "//pkg/syserror", + "//pkg/usermem", "//pkg/waiter", ], ) diff --git a/pkg/sentry/kernel/signalfd/signalfd.go b/pkg/sentry/kernel/signalfd/signalfd.go index 28be4a939..8243bb93e 100644 --- a/pkg/sentry/kernel/signalfd/signalfd.go +++ b/pkg/sentry/kernel/signalfd/signalfd.go @@ -18,14 +18,14 @@ package signalfd import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/binary" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/anon" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/kernel/syscalls.go b/pkg/sentry/kernel/syscalls.go index d2d01add4..93c4fe969 100644 --- a/pkg/sentry/kernel/syscalls.go +++ b/pkg/sentry/kernel/syscalls.go @@ -21,8 +21,8 @@ import ( "gvisor.dev/gvisor/pkg/abi" "gvisor.dev/gvisor/pkg/bits" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" + "gvisor.dev/gvisor/pkg/usermem" ) // maxSyscallNum is the highest supported syscall number. diff --git a/pkg/sentry/kernel/task.go b/pkg/sentry/kernel/task.go index 978d66da8..95adf2778 100644 --- a/pkg/sentry/kernel/task.go +++ b/pkg/sentry/kernel/task.go @@ -21,8 +21,8 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/bpf" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/inet" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" @@ -35,8 +35,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/unimpl" "gvisor.dev/gvisor/pkg/sentry/uniqueid" "gvisor.dev/gvisor/pkg/sentry/usage" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/kernel/task_clone.go b/pkg/sentry/kernel/task_clone.go index 247bd4aba..53d4d211b 100644 --- a/pkg/sentry/kernel/task_clone.go +++ b/pkg/sentry/kernel/task_clone.go @@ -17,8 +17,8 @@ package kernel import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/bpf" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // SharingOptions controls what resources are shared by a new task created by diff --git a/pkg/sentry/kernel/task_context.go b/pkg/sentry/kernel/task_context.go index bb5560acf..2d6e7733c 100644 --- a/pkg/sentry/kernel/task_context.go +++ b/pkg/sentry/kernel/task_context.go @@ -18,13 +18,13 @@ import ( "fmt" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/kernel/futex" "gvisor.dev/gvisor/pkg/sentry/loader" "gvisor.dev/gvisor/pkg/sentry/mm" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserr" + "gvisor.dev/gvisor/pkg/usermem" ) var errNoSyscalls = syserr.New("no syscall table found", linux.ENOEXEC) diff --git a/pkg/sentry/kernel/task_futex.go b/pkg/sentry/kernel/task_futex.go index c211b5b74..a53e77c9f 100644 --- a/pkg/sentry/kernel/task_futex.go +++ b/pkg/sentry/kernel/task_futex.go @@ -16,7 +16,7 @@ package kernel import ( "gvisor.dev/gvisor/pkg/sentry/kernel/futex" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // Futex returns t's futex manager. diff --git a/pkg/sentry/kernel/task_log.go b/pkg/sentry/kernel/task_log.go index 0fb3661de..41259210c 100644 --- a/pkg/sentry/kernel/task_log.go +++ b/pkg/sentry/kernel/task_log.go @@ -20,7 +20,7 @@ import ( "sort" "gvisor.dev/gvisor/pkg/log" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) const ( diff --git a/pkg/sentry/kernel/task_run.go b/pkg/sentry/kernel/task_run.go index 6357273d3..5568c91bc 100644 --- a/pkg/sentry/kernel/task_run.go +++ b/pkg/sentry/kernel/task_run.go @@ -26,7 +26,7 @@ import ( ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/platform" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // A taskRunState is a reified state in the task state machine. See README.md diff --git a/pkg/sentry/kernel/task_signals.go b/pkg/sentry/kernel/task_signals.go index 39cd1340d..8802db142 100644 --- a/pkg/sentry/kernel/task_signals.go +++ b/pkg/sentry/kernel/task_signals.go @@ -26,8 +26,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" ucspb "gvisor.dev/gvisor/pkg/sentry/kernel/uncaught_signal_go_proto" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/kernel/task_start.go b/pkg/sentry/kernel/task_start.go index 58af16ee2..de838beef 100644 --- a/pkg/sentry/kernel/task_start.go +++ b/pkg/sentry/kernel/task_start.go @@ -21,8 +21,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel/futex" "gvisor.dev/gvisor/pkg/sentry/kernel/sched" "gvisor.dev/gvisor/pkg/sentry/usage" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // TaskConfig defines the configuration of a new Task (see below). diff --git a/pkg/sentry/kernel/task_syscall.go b/pkg/sentry/kernel/task_syscall.go index 3180f5560..d555d69a8 100644 --- a/pkg/sentry/kernel/task_syscall.go +++ b/pkg/sentry/kernel/task_syscall.go @@ -25,8 +25,8 @@ import ( "gvisor.dev/gvisor/pkg/metric" "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/memmap" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // SyscallRestartErrno represents a ERESTART* errno defined in the Linux's kernel diff --git a/pkg/sentry/kernel/task_usermem.go b/pkg/sentry/kernel/task_usermem.go index 518bfe1bd..2bf3ce8a8 100644 --- a/pkg/sentry/kernel/task_usermem.go +++ b/pkg/sentry/kernel/task_usermem.go @@ -18,8 +18,8 @@ import ( "math" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // MAX_RW_COUNT is the maximum size in bytes of a single read or write. diff --git a/pkg/sentry/kernel/time/BUILD b/pkg/sentry/kernel/time/BUILD index d49594d9f..7ba7dc50c 100644 --- a/pkg/sentry/kernel/time/BUILD +++ b/pkg/sentry/kernel/time/BUILD @@ -11,7 +11,7 @@ go_library( visibility = ["//pkg/sentry:internal"], deps = [ "//pkg/abi/linux", - "//pkg/sentry/context", + "//pkg/context", "//pkg/sync", "//pkg/syserror", "//pkg/waiter", diff --git a/pkg/sentry/kernel/time/context.go b/pkg/sentry/kernel/time/context.go index 8ef483dd3..00b729d88 100644 --- a/pkg/sentry/kernel/time/context.go +++ b/pkg/sentry/kernel/time/context.go @@ -15,7 +15,7 @@ package time import ( - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" ) // contextID is the time package's type for context.Context.Value keys. diff --git a/pkg/sentry/kernel/timekeeper_test.go b/pkg/sentry/kernel/timekeeper_test.go index 849c5b646..cf2f7ca72 100644 --- a/pkg/sentry/kernel/timekeeper_test.go +++ b/pkg/sentry/kernel/timekeeper_test.go @@ -17,12 +17,12 @@ package kernel import ( "testing" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/sentry/pgalloc" sentrytime "gvisor.dev/gvisor/pkg/sentry/time" "gvisor.dev/gvisor/pkg/sentry/usage" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // mockClocks is a sentrytime.Clocks that simply returns the times in the diff --git a/pkg/sentry/kernel/vdso.go b/pkg/sentry/kernel/vdso.go index fdd10c56c..f1b3c212c 100644 --- a/pkg/sentry/kernel/vdso.go +++ b/pkg/sentry/kernel/vdso.go @@ -18,10 +18,10 @@ import ( "fmt" "gvisor.dev/gvisor/pkg/binary" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/pgalloc" "gvisor.dev/gvisor/pkg/sentry/platform" - "gvisor.dev/gvisor/pkg/sentry/safemem" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // vdsoParams are the parameters exposed to the VDSO. diff --git a/pkg/sentry/limits/BUILD b/pkg/sentry/limits/BUILD index 67869757f..cf591c4c1 100644 --- a/pkg/sentry/limits/BUILD +++ b/pkg/sentry/limits/BUILD @@ -12,7 +12,7 @@ go_library( visibility = ["//:sandbox"], deps = [ "//pkg/abi/linux", - "//pkg/sentry/context", + "//pkg/context", "//pkg/sync", ], ) diff --git a/pkg/sentry/limits/context.go b/pkg/sentry/limits/context.go index 6972749ed..77e1fe217 100644 --- a/pkg/sentry/limits/context.go +++ b/pkg/sentry/limits/context.go @@ -15,7 +15,7 @@ package limits import ( - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" ) // contextID is the limit package's type for context.Context.Value keys. diff --git a/pkg/sentry/loader/BUILD b/pkg/sentry/loader/BUILD index d4ad2bd6c..23790378a 100644 --- a/pkg/sentry/loader/BUILD +++ b/pkg/sentry/loader/BUILD @@ -24,11 +24,12 @@ go_library( "//pkg/abi", "//pkg/abi/linux", "//pkg/binary", + "//pkg/context", "//pkg/cpuid", "//pkg/log", "//pkg/rand", + "//pkg/safemem", "//pkg/sentry/arch", - "//pkg/sentry/context", "//pkg/sentry/fs", "//pkg/sentry/fs/anon", "//pkg/sentry/fs/fsutil", @@ -37,12 +38,11 @@ go_library( "//pkg/sentry/memmap", "//pkg/sentry/mm", "//pkg/sentry/pgalloc", - "//pkg/sentry/safemem", "//pkg/sentry/uniqueid", "//pkg/sentry/usage", - "//pkg/sentry/usermem", "//pkg/syserr", "//pkg/syserror", + "//pkg/usermem", "//pkg/waiter", ], ) diff --git a/pkg/sentry/loader/elf.go b/pkg/sentry/loader/elf.go index 6299a3e2f..122ed05c2 100644 --- a/pkg/sentry/loader/elf.go +++ b/pkg/sentry/loader/elf.go @@ -23,16 +23,16 @@ import ( "gvisor.dev/gvisor/pkg/abi" "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/binary" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/cpuid" "gvisor.dev/gvisor/pkg/log" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/limits" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/mm" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) const ( diff --git a/pkg/sentry/loader/interpreter.go b/pkg/sentry/loader/interpreter.go index ccf909cac..098a45d36 100644 --- a/pkg/sentry/loader/interpreter.go +++ b/pkg/sentry/loader/interpreter.go @@ -18,10 +18,10 @@ import ( "bytes" "io" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) const ( diff --git a/pkg/sentry/loader/loader.go b/pkg/sentry/loader/loader.go index b03eeb005..9a613d6b7 100644 --- a/pkg/sentry/loader/loader.go +++ b/pkg/sentry/loader/loader.go @@ -24,16 +24,16 @@ import ( "gvisor.dev/gvisor/pkg/abi" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/cpuid" "gvisor.dev/gvisor/pkg/rand" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/mm" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserr" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // LoadArgs holds specifications for an executable file to be loaded. diff --git a/pkg/sentry/loader/vdso.go b/pkg/sentry/loader/vdso.go index df8a81907..52f446ed7 100644 --- a/pkg/sentry/loader/vdso.go +++ b/pkg/sentry/loader/vdso.go @@ -20,20 +20,20 @@ import ( "io" "gvisor.dev/gvisor/pkg/abi" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/log" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/anon" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/mm" "gvisor.dev/gvisor/pkg/sentry/pgalloc" - "gvisor.dev/gvisor/pkg/sentry/safemem" "gvisor.dev/gvisor/pkg/sentry/uniqueid" "gvisor.dev/gvisor/pkg/sentry/usage" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/memmap/BUILD b/pkg/sentry/memmap/BUILD index f9a65f086..a98b66de1 100644 --- a/pkg/sentry/memmap/BUILD +++ b/pkg/sentry/memmap/BUILD @@ -38,11 +38,11 @@ go_library( ], visibility = ["//pkg/sentry:internal"], deps = [ + "//pkg/context", "//pkg/log", - "//pkg/sentry/context", "//pkg/sentry/platform", - "//pkg/sentry/usermem", "//pkg/syserror", + "//pkg/usermem", ], ) @@ -51,5 +51,5 @@ go_test( size = "small", srcs = ["mapping_set_test.go"], library = ":memmap", - deps = ["//pkg/sentry/usermem"], + deps = ["//pkg/usermem"], ) diff --git a/pkg/sentry/memmap/mapping_set.go b/pkg/sentry/memmap/mapping_set.go index 0a5b7ce45..d609c1ae0 100644 --- a/pkg/sentry/memmap/mapping_set.go +++ b/pkg/sentry/memmap/mapping_set.go @@ -18,7 +18,7 @@ import ( "fmt" "math" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // MappingSet maps offsets into a Mappable to mappings of those offsets. It is diff --git a/pkg/sentry/memmap/mapping_set_test.go b/pkg/sentry/memmap/mapping_set_test.go index f9b11a59c..d39efe38f 100644 --- a/pkg/sentry/memmap/mapping_set_test.go +++ b/pkg/sentry/memmap/mapping_set_test.go @@ -18,7 +18,7 @@ import ( "reflect" "testing" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) type testMappingSpace struct { diff --git a/pkg/sentry/memmap/memmap.go b/pkg/sentry/memmap/memmap.go index 16a722a13..c6db9fc8f 100644 --- a/pkg/sentry/memmap/memmap.go +++ b/pkg/sentry/memmap/memmap.go @@ -18,9 +18,9 @@ package memmap import ( "fmt" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/platform" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // Mappable represents a memory-mappable object, a mutable mapping from uint64 diff --git a/pkg/sentry/mm/BUILD b/pkg/sentry/mm/BUILD index bd6399fa2..e5729ced5 100644 --- a/pkg/sentry/mm/BUILD +++ b/pkg/sentry/mm/BUILD @@ -27,7 +27,7 @@ go_template_instance( "minDegree": "8", }, imports = { - "usermem": "gvisor.dev/gvisor/pkg/sentry/usermem", + "usermem": "gvisor.dev/gvisor/pkg/usermem", }, package = "mm", prefix = "vma", @@ -47,7 +47,7 @@ go_template_instance( "minDegree": "8", }, imports = { - "usermem": "gvisor.dev/gvisor/pkg/sentry/usermem", + "usermem": "gvisor.dev/gvisor/pkg/usermem", }, package = "mm", prefix = "pma", @@ -99,10 +99,12 @@ go_library( deps = [ "//pkg/abi/linux", "//pkg/atomicbitops", + "//pkg/context", "//pkg/log", "//pkg/refs", + "//pkg/safecopy", + "//pkg/safemem", "//pkg/sentry/arch", - "//pkg/sentry/context", "//pkg/sentry/fs", "//pkg/sentry/fs/proc/seqfile", "//pkg/sentry/kernel/auth", @@ -112,13 +114,11 @@ go_library( "//pkg/sentry/memmap", "//pkg/sentry/pgalloc", "//pkg/sentry/platform", - "//pkg/sentry/platform/safecopy", - "//pkg/sentry/safemem", "//pkg/sentry/usage", - "//pkg/sentry/usermem", "//pkg/sync", "//pkg/syserror", "//pkg/tcpip/buffer", + "//pkg/usermem", ], ) @@ -128,14 +128,14 @@ go_test( srcs = ["mm_test.go"], library = ":mm", deps = [ + "//pkg/context", "//pkg/sentry/arch", - "//pkg/sentry/context", - "//pkg/sentry/context/contexttest", + "//pkg/sentry/contexttest", "//pkg/sentry/limits", "//pkg/sentry/memmap", "//pkg/sentry/pgalloc", "//pkg/sentry/platform", - "//pkg/sentry/usermem", "//pkg/syserror", + "//pkg/usermem", ], ) diff --git a/pkg/sentry/mm/address_space.go b/pkg/sentry/mm/address_space.go index cfebcfd42..e58a63deb 100644 --- a/pkg/sentry/mm/address_space.go +++ b/pkg/sentry/mm/address_space.go @@ -20,7 +20,7 @@ import ( "gvisor.dev/gvisor/pkg/atomicbitops" "gvisor.dev/gvisor/pkg/sentry/platform" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // AddressSpace returns the platform.AddressSpace bound to mm. diff --git a/pkg/sentry/mm/aio_context.go b/pkg/sentry/mm/aio_context.go index 4b48866ad..cb29d94b0 100644 --- a/pkg/sentry/mm/aio_context.go +++ b/pkg/sentry/mm/aio_context.go @@ -16,15 +16,15 @@ package mm import ( "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/refs" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/pgalloc" "gvisor.dev/gvisor/pkg/sentry/platform" "gvisor.dev/gvisor/pkg/sentry/usage" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // aioManager creates and manages asynchronous I/O contexts. diff --git a/pkg/sentry/mm/debug.go b/pkg/sentry/mm/debug.go index df9adf708..c273c982e 100644 --- a/pkg/sentry/mm/debug.go +++ b/pkg/sentry/mm/debug.go @@ -18,7 +18,7 @@ import ( "bytes" "fmt" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" ) const ( diff --git a/pkg/sentry/mm/io.go b/pkg/sentry/mm/io.go index b03e7d020..fa776f9c6 100644 --- a/pkg/sentry/mm/io.go +++ b/pkg/sentry/mm/io.go @@ -15,11 +15,11 @@ package mm import ( - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/platform" - "gvisor.dev/gvisor/pkg/sentry/safemem" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // There are two supported ways to copy data to/from application virtual diff --git a/pkg/sentry/mm/lifecycle.go b/pkg/sentry/mm/lifecycle.go index 4e9ca1de6..47b8fbf43 100644 --- a/pkg/sentry/mm/lifecycle.go +++ b/pkg/sentry/mm/lifecycle.go @@ -19,13 +19,13 @@ import ( "sync/atomic" "gvisor.dev/gvisor/pkg/atomicbitops" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/limits" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/pgalloc" "gvisor.dev/gvisor/pkg/sentry/platform" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // NewMemoryManager returns a new MemoryManager with no mappings and 1 user. diff --git a/pkg/sentry/mm/metadata.go b/pkg/sentry/mm/metadata.go index d2a01d48a..f550acae0 100644 --- a/pkg/sentry/mm/metadata.go +++ b/pkg/sentry/mm/metadata.go @@ -17,7 +17,7 @@ package mm import ( "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/fs" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // Dumpability describes if and how core dumps should be created. diff --git a/pkg/sentry/mm/mm.go b/pkg/sentry/mm/mm.go index 78cc9e6e4..09e582dd3 100644 --- a/pkg/sentry/mm/mm.go +++ b/pkg/sentry/mm/mm.go @@ -35,14 +35,14 @@ package mm import ( + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/pgalloc" "gvisor.dev/gvisor/pkg/sentry/platform" - "gvisor.dev/gvisor/pkg/sentry/safemem" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" + "gvisor.dev/gvisor/pkg/usermem" ) // MemoryManager implements a virtual address space. diff --git a/pkg/sentry/mm/mm_test.go b/pkg/sentry/mm/mm_test.go index 4d2bfaaed..edacca741 100644 --- a/pkg/sentry/mm/mm_test.go +++ b/pkg/sentry/mm/mm_test.go @@ -17,15 +17,15 @@ package mm import ( "testing" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/sentry/limits" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/pgalloc" "gvisor.dev/gvisor/pkg/sentry/platform" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) func testMemoryManager(ctx context.Context) *MemoryManager { diff --git a/pkg/sentry/mm/pma.go b/pkg/sentry/mm/pma.go index c976c6f45..62e4c20af 100644 --- a/pkg/sentry/mm/pma.go +++ b/pkg/sentry/mm/pma.go @@ -17,14 +17,14 @@ package mm import ( "fmt" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/safecopy" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/platform" - "gvisor.dev/gvisor/pkg/sentry/platform/safecopy" - "gvisor.dev/gvisor/pkg/sentry/safemem" "gvisor.dev/gvisor/pkg/sentry/usage" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // existingPMAsLocked checks that pmas exist for all addresses in ar, and diff --git a/pkg/sentry/mm/procfs.go b/pkg/sentry/mm/procfs.go index 79610acb7..1ab92f046 100644 --- a/pkg/sentry/mm/procfs.go +++ b/pkg/sentry/mm/procfs.go @@ -19,10 +19,10 @@ import ( "fmt" "strings" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs/proc/seqfile" "gvisor.dev/gvisor/pkg/sentry/memmap" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) const ( diff --git a/pkg/sentry/mm/save_restore.go b/pkg/sentry/mm/save_restore.go index 93259c5a3..f56215d9a 100644 --- a/pkg/sentry/mm/save_restore.go +++ b/pkg/sentry/mm/save_restore.go @@ -17,7 +17,7 @@ package mm import ( "fmt" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" ) // InvalidateUnsavable invokes memmap.Mappable.InvalidateUnsavable on all diff --git a/pkg/sentry/mm/shm.go b/pkg/sentry/mm/shm.go index b9f2d23e5..6432731d4 100644 --- a/pkg/sentry/mm/shm.go +++ b/pkg/sentry/mm/shm.go @@ -15,10 +15,10 @@ package mm import ( - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/kernel/shm" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // DetachShm unmaps a sysv shared memory segment. diff --git a/pkg/sentry/mm/special_mappable.go b/pkg/sentry/mm/special_mappable.go index ea2d7af74..9ad52082d 100644 --- a/pkg/sentry/mm/special_mappable.go +++ b/pkg/sentry/mm/special_mappable.go @@ -15,14 +15,14 @@ package mm import ( + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/refs" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/pgalloc" "gvisor.dev/gvisor/pkg/sentry/platform" "gvisor.dev/gvisor/pkg/sentry/usage" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // SpecialMappable implements memmap.MappingIdentity and memmap.Mappable with diff --git a/pkg/sentry/mm/syscalls.go b/pkg/sentry/mm/syscalls.go index c2466c988..c5dfa5972 100644 --- a/pkg/sentry/mm/syscalls.go +++ b/pkg/sentry/mm/syscalls.go @@ -19,14 +19,14 @@ import ( mrand "math/rand" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/kernel/futex" "gvisor.dev/gvisor/pkg/sentry/limits" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/pgalloc" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // HandleUserFault handles an application page fault. sp is the faulting diff --git a/pkg/sentry/mm/vma.go b/pkg/sentry/mm/vma.go index f2fd70799..9a14e69e6 100644 --- a/pkg/sentry/mm/vma.go +++ b/pkg/sentry/mm/vma.go @@ -18,13 +18,13 @@ import ( "fmt" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/limits" "gvisor.dev/gvisor/pkg/sentry/memmap" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // Preconditions: mm.mappingMu must be locked for writing. opts must be valid diff --git a/pkg/sentry/pgalloc/BUILD b/pkg/sentry/pgalloc/BUILD index 02385a3ce..1eeb9f317 100644 --- a/pkg/sentry/pgalloc/BUILD +++ b/pkg/sentry/pgalloc/BUILD @@ -61,18 +61,18 @@ go_library( ], visibility = ["//pkg/sentry:internal"], deps = [ + "//pkg/context", "//pkg/log", "//pkg/memutil", + "//pkg/safemem", "//pkg/sentry/arch", - "//pkg/sentry/context", "//pkg/sentry/hostmm", "//pkg/sentry/platform", - "//pkg/sentry/safemem", "//pkg/sentry/usage", - "//pkg/sentry/usermem", "//pkg/state", "//pkg/sync", "//pkg/syserror", + "//pkg/usermem", ], ) @@ -81,5 +81,5 @@ go_test( size = "small", srcs = ["pgalloc_test.go"], library = ":pgalloc", - deps = ["//pkg/sentry/usermem"], + deps = ["//pkg/usermem"], ) diff --git a/pkg/sentry/pgalloc/context.go b/pkg/sentry/pgalloc/context.go index 11ccf897b..d25215418 100644 --- a/pkg/sentry/pgalloc/context.go +++ b/pkg/sentry/pgalloc/context.go @@ -15,7 +15,7 @@ package pgalloc import ( - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" ) // contextID is this package's type for context.Context.Value keys. diff --git a/pkg/sentry/pgalloc/pgalloc.go b/pkg/sentry/pgalloc/pgalloc.go index c99e023d9..577e9306a 100644 --- a/pkg/sentry/pgalloc/pgalloc.go +++ b/pkg/sentry/pgalloc/pgalloc.go @@ -29,15 +29,15 @@ import ( "syscall" "time" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/log" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/hostmm" "gvisor.dev/gvisor/pkg/sentry/platform" - "gvisor.dev/gvisor/pkg/sentry/safemem" "gvisor.dev/gvisor/pkg/sentry/usage" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // MemoryFile is a platform.File whose pages may be allocated to arbitrary diff --git a/pkg/sentry/pgalloc/pgalloc_test.go b/pkg/sentry/pgalloc/pgalloc_test.go index 428e6a859..293f22c6b 100644 --- a/pkg/sentry/pgalloc/pgalloc_test.go +++ b/pkg/sentry/pgalloc/pgalloc_test.go @@ -17,7 +17,7 @@ package pgalloc import ( "testing" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) const ( diff --git a/pkg/sentry/pgalloc/save_restore.go b/pkg/sentry/pgalloc/save_restore.go index aafce1d00..f8385c146 100644 --- a/pkg/sentry/pgalloc/save_restore.go +++ b/pkg/sentry/pgalloc/save_restore.go @@ -25,8 +25,8 @@ import ( "gvisor.dev/gvisor/pkg/log" "gvisor.dev/gvisor/pkg/sentry/usage" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/state" + "gvisor.dev/gvisor/pkg/usermem" ) // SaveTo writes f's state to the given stream. diff --git a/pkg/sentry/platform/BUILD b/pkg/sentry/platform/BUILD index 006450b2d..453241eca 100644 --- a/pkg/sentry/platform/BUILD +++ b/pkg/sentry/platform/BUILD @@ -26,14 +26,14 @@ go_library( deps = [ "//pkg/abi/linux", "//pkg/atomicbitops", + "//pkg/context", "//pkg/log", + "//pkg/safecopy", + "//pkg/safemem", "//pkg/seccomp", "//pkg/sentry/arch", - "//pkg/sentry/context", - "//pkg/sentry/platform/safecopy", - "//pkg/sentry/safemem", "//pkg/sentry/usage", - "//pkg/sentry/usermem", "//pkg/syserror", + "//pkg/usermem", ], ) diff --git a/pkg/sentry/platform/context.go b/pkg/sentry/platform/context.go index e29bc4485..6759cda65 100644 --- a/pkg/sentry/platform/context.go +++ b/pkg/sentry/platform/context.go @@ -15,7 +15,7 @@ package platform import ( - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" ) // contextID is the auth package's type for context.Context.Value keys. diff --git a/pkg/sentry/platform/kvm/BUILD b/pkg/sentry/platform/kvm/BUILD index a4532a766..159f7eafd 100644 --- a/pkg/sentry/platform/kvm/BUILD +++ b/pkg/sentry/platform/kvm/BUILD @@ -44,16 +44,16 @@ go_library( "//pkg/cpuid", "//pkg/log", "//pkg/procid", + "//pkg/safecopy", "//pkg/seccomp", "//pkg/sentry/arch", "//pkg/sentry/platform", "//pkg/sentry/platform/interrupt", "//pkg/sentry/platform/ring0", "//pkg/sentry/platform/ring0/pagetables", - "//pkg/sentry/platform/safecopy", "//pkg/sentry/time", - "//pkg/sentry/usermem", "//pkg/sync", + "//pkg/usermem", ], ) @@ -75,6 +75,6 @@ go_test( "//pkg/sentry/platform/kvm/testutil", "//pkg/sentry/platform/ring0", "//pkg/sentry/platform/ring0/pagetables", - "//pkg/sentry/usermem", + "//pkg/usermem", ], ) diff --git a/pkg/sentry/platform/kvm/address_space.go b/pkg/sentry/platform/kvm/address_space.go index a25f3c449..be213bfe8 100644 --- a/pkg/sentry/platform/kvm/address_space.go +++ b/pkg/sentry/platform/kvm/address_space.go @@ -20,8 +20,8 @@ import ( "gvisor.dev/gvisor/pkg/atomicbitops" "gvisor.dev/gvisor/pkg/sentry/platform" "gvisor.dev/gvisor/pkg/sentry/platform/ring0/pagetables" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" + "gvisor.dev/gvisor/pkg/usermem" ) // dirtySet tracks vCPUs for invalidation. diff --git a/pkg/sentry/platform/kvm/bluepill.go b/pkg/sentry/platform/kvm/bluepill.go index 30dbb74d6..35cd55fef 100644 --- a/pkg/sentry/platform/kvm/bluepill.go +++ b/pkg/sentry/platform/kvm/bluepill.go @@ -19,9 +19,9 @@ import ( "reflect" "syscall" + "gvisor.dev/gvisor/pkg/safecopy" "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/platform/ring0" - "gvisor.dev/gvisor/pkg/sentry/platform/safecopy" ) // bluepill enters guest mode. diff --git a/pkg/sentry/platform/kvm/bluepill_fault.go b/pkg/sentry/platform/kvm/bluepill_fault.go index f6459cda9..e34f46aeb 100644 --- a/pkg/sentry/platform/kvm/bluepill_fault.go +++ b/pkg/sentry/platform/kvm/bluepill_fault.go @@ -18,7 +18,7 @@ import ( "sync/atomic" "syscall" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) const ( diff --git a/pkg/sentry/platform/kvm/context.go b/pkg/sentry/platform/kvm/context.go index 99450d22d..c769ac7b4 100644 --- a/pkg/sentry/platform/kvm/context.go +++ b/pkg/sentry/platform/kvm/context.go @@ -19,7 +19,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/platform" "gvisor.dev/gvisor/pkg/sentry/platform/interrupt" "gvisor.dev/gvisor/pkg/sentry/platform/ring0" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // context is an implementation of the platform context. diff --git a/pkg/sentry/platform/kvm/kvm.go b/pkg/sentry/platform/kvm/kvm.go index d337c5c7c..972ba85c3 100644 --- a/pkg/sentry/platform/kvm/kvm.go +++ b/pkg/sentry/platform/kvm/kvm.go @@ -23,8 +23,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/platform" "gvisor.dev/gvisor/pkg/sentry/platform/ring0" "gvisor.dev/gvisor/pkg/sentry/platform/ring0/pagetables" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" + "gvisor.dev/gvisor/pkg/usermem" ) // KVM represents a lightweight VM context. diff --git a/pkg/sentry/platform/kvm/kvm_test.go b/pkg/sentry/platform/kvm/kvm_test.go index 30df725d4..c42752d50 100644 --- a/pkg/sentry/platform/kvm/kvm_test.go +++ b/pkg/sentry/platform/kvm/kvm_test.go @@ -27,7 +27,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/platform/kvm/testutil" "gvisor.dev/gvisor/pkg/sentry/platform/ring0" "gvisor.dev/gvisor/pkg/sentry/platform/ring0/pagetables" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) var dummyFPState = (*byte)(arch.NewFloatingPointData()) diff --git a/pkg/sentry/platform/kvm/machine.go b/pkg/sentry/platform/kvm/machine.go index e6d912168..8076c7529 100644 --- a/pkg/sentry/platform/kvm/machine.go +++ b/pkg/sentry/platform/kvm/machine.go @@ -25,8 +25,8 @@ import ( "gvisor.dev/gvisor/pkg/procid" "gvisor.dev/gvisor/pkg/sentry/platform/ring0" "gvisor.dev/gvisor/pkg/sentry/platform/ring0/pagetables" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" + "gvisor.dev/gvisor/pkg/usermem" ) // machine contains state associated with the VM as a whole. diff --git a/pkg/sentry/platform/kvm/machine_amd64.go b/pkg/sentry/platform/kvm/machine_amd64.go index 873e39dc7..923ce3909 100644 --- a/pkg/sentry/platform/kvm/machine_amd64.go +++ b/pkg/sentry/platform/kvm/machine_amd64.go @@ -26,7 +26,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/platform" "gvisor.dev/gvisor/pkg/sentry/platform/ring0" "gvisor.dev/gvisor/pkg/sentry/platform/ring0/pagetables" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // initArchState initializes architecture-specific state. diff --git a/pkg/sentry/platform/kvm/machine_arm64.go b/pkg/sentry/platform/kvm/machine_arm64.go index 3b1f20219..09552837a 100644 --- a/pkg/sentry/platform/kvm/machine_arm64.go +++ b/pkg/sentry/platform/kvm/machine_arm64.go @@ -20,7 +20,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/platform" "gvisor.dev/gvisor/pkg/sentry/platform/ring0/pagetables" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) type vCPUArchState struct { diff --git a/pkg/sentry/platform/kvm/machine_arm64_unsafe.go b/pkg/sentry/platform/kvm/machine_arm64_unsafe.go index 3f2f97a6b..1c8384e6b 100644 --- a/pkg/sentry/platform/kvm/machine_arm64_unsafe.go +++ b/pkg/sentry/platform/kvm/machine_arm64_unsafe.go @@ -26,7 +26,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/platform" "gvisor.dev/gvisor/pkg/sentry/platform/ring0" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // setMemoryRegion initializes a region. diff --git a/pkg/sentry/platform/kvm/physical_map.go b/pkg/sentry/platform/kvm/physical_map.go index 91de5dab1..f7fa2f98d 100644 --- a/pkg/sentry/platform/kvm/physical_map.go +++ b/pkg/sentry/platform/kvm/physical_map.go @@ -21,7 +21,7 @@ import ( "gvisor.dev/gvisor/pkg/log" "gvisor.dev/gvisor/pkg/sentry/platform/ring0" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) type region struct { diff --git a/pkg/sentry/platform/kvm/virtual_map.go b/pkg/sentry/platform/kvm/virtual_map.go index 2d68855ef..c8897d34f 100644 --- a/pkg/sentry/platform/kvm/virtual_map.go +++ b/pkg/sentry/platform/kvm/virtual_map.go @@ -22,7 +22,7 @@ import ( "regexp" "strconv" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) type virtualRegion struct { diff --git a/pkg/sentry/platform/kvm/virtual_map_test.go b/pkg/sentry/platform/kvm/virtual_map_test.go index 6a2f145be..327e2be4f 100644 --- a/pkg/sentry/platform/kvm/virtual_map_test.go +++ b/pkg/sentry/platform/kvm/virtual_map_test.go @@ -18,7 +18,7 @@ import ( "syscall" "testing" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) type checker struct { diff --git a/pkg/sentry/platform/mmap_min_addr.go b/pkg/sentry/platform/mmap_min_addr.go index 999787462..091c2e365 100644 --- a/pkg/sentry/platform/mmap_min_addr.go +++ b/pkg/sentry/platform/mmap_min_addr.go @@ -20,7 +20,7 @@ import ( "strconv" "strings" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // systemMMapMinAddrSource is the source file. diff --git a/pkg/sentry/platform/platform.go b/pkg/sentry/platform/platform.go index ec22dbf87..2ca696382 100644 --- a/pkg/sentry/platform/platform.go +++ b/pkg/sentry/platform/platform.go @@ -22,10 +22,10 @@ import ( "os" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/seccomp" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/safemem" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // Platform provides abstractions for execution contexts (Context, diff --git a/pkg/sentry/platform/ptrace/BUILD b/pkg/sentry/platform/ptrace/BUILD index 3bcc5e040..95abd321e 100644 --- a/pkg/sentry/platform/ptrace/BUILD +++ b/pkg/sentry/platform/ptrace/BUILD @@ -25,14 +25,14 @@ go_library( "//pkg/abi/linux", "//pkg/log", "//pkg/procid", + "//pkg/safecopy", "//pkg/seccomp", "//pkg/sentry/arch", "//pkg/sentry/hostcpu", "//pkg/sentry/platform", "//pkg/sentry/platform/interrupt", - "//pkg/sentry/platform/safecopy", - "//pkg/sentry/usermem", "//pkg/sync", + "//pkg/usermem", "@org_golang_x_sys//unix:go_default_library", ], ) diff --git a/pkg/sentry/platform/ptrace/ptrace.go b/pkg/sentry/platform/ptrace/ptrace.go index bb0e03880..03adb624b 100644 --- a/pkg/sentry/platform/ptrace/ptrace.go +++ b/pkg/sentry/platform/ptrace/ptrace.go @@ -51,8 +51,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/platform" "gvisor.dev/gvisor/pkg/sentry/platform/interrupt" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" + "gvisor.dev/gvisor/pkg/usermem" ) var ( diff --git a/pkg/sentry/platform/ptrace/ptrace_unsafe.go b/pkg/sentry/platform/ptrace/ptrace_unsafe.go index 72c7ec564..6c0ed7b3e 100644 --- a/pkg/sentry/platform/ptrace/ptrace_unsafe.go +++ b/pkg/sentry/platform/ptrace/ptrace_unsafe.go @@ -20,7 +20,7 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // getRegs gets the general purpose register set. diff --git a/pkg/sentry/platform/ptrace/stub_unsafe.go b/pkg/sentry/platform/ptrace/stub_unsafe.go index aa1b87237..341dde143 100644 --- a/pkg/sentry/platform/ptrace/stub_unsafe.go +++ b/pkg/sentry/platform/ptrace/stub_unsafe.go @@ -19,8 +19,8 @@ import ( "syscall" "unsafe" - "gvisor.dev/gvisor/pkg/sentry/platform/safecopy" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/safecopy" + "gvisor.dev/gvisor/pkg/usermem" ) // stub is defined in arch-specific assembly. diff --git a/pkg/sentry/platform/ptrace/subprocess.go b/pkg/sentry/platform/ptrace/subprocess.go index 15dc46a5b..31b7cec53 100644 --- a/pkg/sentry/platform/ptrace/subprocess.go +++ b/pkg/sentry/platform/ptrace/subprocess.go @@ -25,8 +25,8 @@ import ( "gvisor.dev/gvisor/pkg/procid" "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/platform" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" + "gvisor.dev/gvisor/pkg/usermem" ) // Linux kernel errnos which "should never be seen by user programs", but will diff --git a/pkg/sentry/platform/ring0/BUILD b/pkg/sentry/platform/ring0/BUILD index 6dee8fcc5..934b6fbcd 100644 --- a/pkg/sentry/platform/ring0/BUILD +++ b/pkg/sentry/platform/ring0/BUILD @@ -78,6 +78,6 @@ go_library( deps = [ "//pkg/cpuid", "//pkg/sentry/platform/ring0/pagetables", - "//pkg/sentry/usermem", + "//pkg/usermem", ], ) diff --git a/pkg/sentry/platform/ring0/defs_amd64.go b/pkg/sentry/platform/ring0/defs_amd64.go index 9dae0dccb..9c6c2cf5c 100644 --- a/pkg/sentry/platform/ring0/defs_amd64.go +++ b/pkg/sentry/platform/ring0/defs_amd64.go @@ -18,7 +18,7 @@ package ring0 import ( "gvisor.dev/gvisor/pkg/sentry/platform/ring0/pagetables" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) var ( diff --git a/pkg/sentry/platform/ring0/defs_arm64.go b/pkg/sentry/platform/ring0/defs_arm64.go index a850ce6cf..1583dda12 100644 --- a/pkg/sentry/platform/ring0/defs_arm64.go +++ b/pkg/sentry/platform/ring0/defs_arm64.go @@ -18,7 +18,7 @@ package ring0 import ( "gvisor.dev/gvisor/pkg/sentry/platform/ring0/pagetables" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) var ( diff --git a/pkg/sentry/platform/ring0/gen_offsets/BUILD b/pkg/sentry/platform/ring0/gen_offsets/BUILD index 147311ed3..4cae10459 100644 --- a/pkg/sentry/platform/ring0/gen_offsets/BUILD +++ b/pkg/sentry/platform/ring0/gen_offsets/BUILD @@ -28,6 +28,6 @@ go_binary( deps = [ "//pkg/cpuid", "//pkg/sentry/platform/ring0/pagetables", - "//pkg/sentry/usermem", + "//pkg/usermem", ], ) diff --git a/pkg/sentry/platform/ring0/pagetables/BUILD b/pkg/sentry/platform/ring0/pagetables/BUILD index 8b5cdd6c1..971eed7fa 100644 --- a/pkg/sentry/platform/ring0/pagetables/BUILD +++ b/pkg/sentry/platform/ring0/pagetables/BUILD @@ -93,8 +93,8 @@ go_library( "//pkg/sentry/platform/ring0:__subpackages__", ], deps = [ - "//pkg/sentry/usermem", "//pkg/sync", + "//pkg/usermem", ], ) @@ -108,5 +108,5 @@ go_test( "walker_check.go", ], library = ":pagetables", - deps = ["//pkg/sentry/usermem"], + deps = ["//pkg/usermem"], ) diff --git a/pkg/sentry/platform/ring0/pagetables/allocator_unsafe.go b/pkg/sentry/platform/ring0/pagetables/allocator_unsafe.go index a90394a33..d08bfdeb3 100644 --- a/pkg/sentry/platform/ring0/pagetables/allocator_unsafe.go +++ b/pkg/sentry/platform/ring0/pagetables/allocator_unsafe.go @@ -17,7 +17,7 @@ package pagetables import ( "unsafe" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // newAlignedPTEs returns a set of aligned PTEs. diff --git a/pkg/sentry/platform/ring0/pagetables/pagetables.go b/pkg/sentry/platform/ring0/pagetables/pagetables.go index 30c64a372..87e88e97d 100644 --- a/pkg/sentry/platform/ring0/pagetables/pagetables.go +++ b/pkg/sentry/platform/ring0/pagetables/pagetables.go @@ -21,7 +21,7 @@ package pagetables import ( - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // PageTables is a set of page tables. diff --git a/pkg/sentry/platform/ring0/pagetables/pagetables_aarch64.go b/pkg/sentry/platform/ring0/pagetables/pagetables_aarch64.go index e78424766..78510ebed 100644 --- a/pkg/sentry/platform/ring0/pagetables/pagetables_aarch64.go +++ b/pkg/sentry/platform/ring0/pagetables/pagetables_aarch64.go @@ -19,7 +19,7 @@ package pagetables import ( "sync/atomic" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // archPageTables is architecture-specific data. diff --git a/pkg/sentry/platform/ring0/pagetables/pagetables_amd64_test.go b/pkg/sentry/platform/ring0/pagetables/pagetables_amd64_test.go index 35e917526..54e8e554f 100644 --- a/pkg/sentry/platform/ring0/pagetables/pagetables_amd64_test.go +++ b/pkg/sentry/platform/ring0/pagetables/pagetables_amd64_test.go @@ -19,7 +19,7 @@ package pagetables import ( "testing" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) func Test2MAnd4K(t *testing.T) { diff --git a/pkg/sentry/platform/ring0/pagetables/pagetables_arm64_test.go b/pkg/sentry/platform/ring0/pagetables/pagetables_arm64_test.go index 254116233..2f73d424f 100644 --- a/pkg/sentry/platform/ring0/pagetables/pagetables_arm64_test.go +++ b/pkg/sentry/platform/ring0/pagetables/pagetables_arm64_test.go @@ -19,7 +19,7 @@ package pagetables import ( "testing" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) func Test2MAnd4K(t *testing.T) { diff --git a/pkg/sentry/platform/ring0/pagetables/pagetables_test.go b/pkg/sentry/platform/ring0/pagetables/pagetables_test.go index 6e95ad2b9..5c88d087d 100644 --- a/pkg/sentry/platform/ring0/pagetables/pagetables_test.go +++ b/pkg/sentry/platform/ring0/pagetables/pagetables_test.go @@ -17,7 +17,7 @@ package pagetables import ( "testing" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) type mapping struct { diff --git a/pkg/sentry/platform/ring0/pagetables/pagetables_x86.go b/pkg/sentry/platform/ring0/pagetables/pagetables_x86.go index 3e2383c5e..dcf061df9 100644 --- a/pkg/sentry/platform/ring0/pagetables/pagetables_x86.go +++ b/pkg/sentry/platform/ring0/pagetables/pagetables_x86.go @@ -19,7 +19,7 @@ package pagetables import ( "sync/atomic" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // archPageTables is architecture-specific data. diff --git a/pkg/sentry/platform/safecopy/BUILD b/pkg/sentry/platform/safecopy/BUILD deleted file mode 100644 index b8747585b..000000000 --- a/pkg/sentry/platform/safecopy/BUILD +++ /dev/null @@ -1,29 +0,0 @@ -load("//tools:defs.bzl", "go_library", "go_test") - -package(licenses = ["notice"]) - -go_library( - name = "safecopy", - srcs = [ - "atomic_amd64.s", - "atomic_arm64.s", - "memclr_amd64.s", - "memclr_arm64.s", - "memcpy_amd64.s", - "memcpy_arm64.s", - "safecopy.go", - "safecopy_unsafe.go", - "sighandler_amd64.s", - "sighandler_arm64.s", - ], - visibility = ["//pkg/sentry:internal"], - deps = ["//pkg/syserror"], -) - -go_test( - name = "safecopy_test", - srcs = [ - "safecopy_test.go", - ], - library = ":safecopy", -) diff --git a/pkg/sentry/platform/safecopy/LICENSE b/pkg/sentry/platform/safecopy/LICENSE deleted file mode 100644 index 6a66aea5e..000000000 --- a/pkg/sentry/platform/safecopy/LICENSE +++ /dev/null @@ -1,27 +0,0 @@ -Copyright (c) 2009 The Go Authors. All rights reserved. - -Redistribution and use in source and binary forms, with or without -modification, are permitted provided that the following conditions are -met: - - * Redistributions of source code must retain the above copyright -notice, this list of conditions and the following disclaimer. - * Redistributions in binary form must reproduce the above -copyright notice, this list of conditions and the following disclaimer -in the documentation and/or other materials provided with the -distribution. - * Neither the name of Google Inc. nor the names of its -contributors may be used to endorse or promote products derived from -this software without specific prior written permission. - -THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS -"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT -LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR -A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT -OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, -SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT -LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, -DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY -THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT -(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE -OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. diff --git a/pkg/sentry/platform/safecopy/atomic_amd64.s b/pkg/sentry/platform/safecopy/atomic_amd64.s deleted file mode 100644 index a0cd78f33..000000000 --- a/pkg/sentry/platform/safecopy/atomic_amd64.s +++ /dev/null @@ -1,136 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -#include "textflag.h" - -// handleSwapUint32Fault returns the value stored in DI. Control is transferred -// to it when swapUint32 below receives SIGSEGV or SIGBUS, with the signal -// number stored in DI. -// -// It must have the same frame configuration as swapUint32 so that it can undo -// any potential call frame set up by the assembler. -TEXT handleSwapUint32Fault(SB), NOSPLIT, $0-24 - MOVL DI, sig+20(FP) - RET - -// swapUint32 atomically stores new into *addr and returns (the previous *addr -// value, 0). If a SIGSEGV or SIGBUS signal is received during the swap, the -// value of old is unspecified, and sig is the number of the signal that was -// received. -// -// Preconditions: addr must be aligned to a 4-byte boundary. -// -//func swapUint32(ptr unsafe.Pointer, new uint32) (old uint32, sig int32) -TEXT ·swapUint32(SB), NOSPLIT, $0-24 - // Store 0 as the returned signal number. If we run to completion, - // this is the value the caller will see; if a signal is received, - // handleSwapUint32Fault will store a different value in this address. - MOVL $0, sig+20(FP) - - MOVQ addr+0(FP), DI - MOVL new+8(FP), AX - XCHGL AX, 0(DI) - MOVL AX, old+16(FP) - RET - -// handleSwapUint64Fault returns the value stored in DI. Control is transferred -// to it when swapUint64 below receives SIGSEGV or SIGBUS, with the signal -// number stored in DI. -// -// It must have the same frame configuration as swapUint64 so that it can undo -// any potential call frame set up by the assembler. -TEXT handleSwapUint64Fault(SB), NOSPLIT, $0-28 - MOVL DI, sig+24(FP) - RET - -// swapUint64 atomically stores new into *addr and returns (the previous *addr -// value, 0). If a SIGSEGV or SIGBUS signal is received during the swap, the -// value of old is unspecified, and sig is the number of the signal that was -// received. -// -// Preconditions: addr must be aligned to a 8-byte boundary. -// -//func swapUint64(ptr unsafe.Pointer, new uint64) (old uint64, sig int32) -TEXT ·swapUint64(SB), NOSPLIT, $0-28 - // Store 0 as the returned signal number. If we run to completion, - // this is the value the caller will see; if a signal is received, - // handleSwapUint64Fault will store a different value in this address. - MOVL $0, sig+24(FP) - - MOVQ addr+0(FP), DI - MOVQ new+8(FP), AX - XCHGQ AX, 0(DI) - MOVQ AX, old+16(FP) - RET - -// handleCompareAndSwapUint32Fault returns the value stored in DI. Control is -// transferred to it when swapUint64 below receives SIGSEGV or SIGBUS, with the -// signal number stored in DI. -// -// It must have the same frame configuration as compareAndSwapUint32 so that it -// can undo any potential call frame set up by the assembler. -TEXT handleCompareAndSwapUint32Fault(SB), NOSPLIT, $0-24 - MOVL DI, sig+20(FP) - RET - -// compareAndSwapUint32 is like sync/atomic.CompareAndSwapUint32, but returns -// (the value previously stored at addr, 0). If a SIGSEGV or SIGBUS signal is -// received during the operation, the value of prev is unspecified, and sig is -// the number of the signal that was received. -// -// Preconditions: addr must be aligned to a 4-byte boundary. -// -//func compareAndSwapUint32(ptr unsafe.Pointer, old, new uint32) (prev uint32, sig int32) -TEXT ·compareAndSwapUint32(SB), NOSPLIT, $0-24 - // Store 0 as the returned signal number. If we run to completion, this is - // the value the caller will see; if a signal is received, - // handleCompareAndSwapUint32Fault will store a different value in this - // address. - MOVL $0, sig+20(FP) - - MOVQ addr+0(FP), DI - MOVL old+8(FP), AX - MOVL new+12(FP), DX - LOCK - CMPXCHGL DX, 0(DI) - MOVL AX, prev+16(FP) - RET - -// handleLoadUint32Fault returns the value stored in DI. Control is transferred -// to it when LoadUint32 below receives SIGSEGV or SIGBUS, with the signal -// number stored in DI. -// -// It must have the same frame configuration as loadUint32 so that it can undo -// any potential call frame set up by the assembler. -TEXT handleLoadUint32Fault(SB), NOSPLIT, $0-16 - MOVL DI, sig+12(FP) - RET - -// loadUint32 atomically loads *addr and returns it. If a SIGSEGV or SIGBUS -// signal is received, the value returned is unspecified, and sig is the number -// of the signal that was received. -// -// Preconditions: addr must be aligned to a 4-byte boundary. -// -//func loadUint32(ptr unsafe.Pointer) (val uint32, sig int32) -TEXT ·loadUint32(SB), NOSPLIT, $0-16 - // Store 0 as the returned signal number. If we run to completion, - // this is the value the caller will see; if a signal is received, - // handleLoadUint32Fault will store a different value in this address. - MOVL $0, sig+12(FP) - - MOVQ addr+0(FP), AX - MOVL (AX), BX - MOVL BX, val+8(FP) - RET diff --git a/pkg/sentry/platform/safecopy/atomic_arm64.s b/pkg/sentry/platform/safecopy/atomic_arm64.s deleted file mode 100644 index d58ed71f7..000000000 --- a/pkg/sentry/platform/safecopy/atomic_arm64.s +++ /dev/null @@ -1,126 +0,0 @@ -// Copyright 2014 The Go Authors. All rights reserved. -// Use of this source code is governed by a BSD-style -// license that can be found in the LICENSE file. - -#include "textflag.h" - -// handleSwapUint32Fault returns the value stored in R1. Control is transferred -// to it when swapUint32 below receives SIGSEGV or SIGBUS, with the signal -// number stored in R1. -// -// It must have the same frame configuration as swapUint32 so that it can undo -// any potential call frame set up by the assembler. -TEXT handleSwapUint32Fault(SB), NOSPLIT, $0-24 - MOVW R1, sig+20(FP) - RET - -// See the corresponding doc in safecopy_unsafe.go -// -// The code is derived from Go source runtime/internal/atomic.Xchg. -// -//func swapUint32(ptr unsafe.Pointer, new uint32) (old uint32, sig int32) -TEXT ·swapUint32(SB), NOSPLIT, $0-24 - // Store 0 as the returned signal number. If we run to completion, - // this is the value the caller will see; if a signal is received, - // handleSwapUint32Fault will store a different value in this address. - MOVW $0, sig+20(FP) -again: - MOVD addr+0(FP), R0 - MOVW new+8(FP), R1 - LDAXRW (R0), R2 - STLXRW R1, (R0), R3 - CBNZ R3, again - MOVW R2, old+16(FP) - RET - -// handleSwapUint64Fault returns the value stored in R1. Control is transferred -// to it when swapUint64 below receives SIGSEGV or SIGBUS, with the signal -// number stored in R1. -// -// It must have the same frame configuration as swapUint64 so that it can undo -// any potential call frame set up by the assembler. -TEXT handleSwapUint64Fault(SB), NOSPLIT, $0-28 - MOVW R1, sig+24(FP) - RET - -// See the corresponding doc in safecopy_unsafe.go -// -// The code is derived from Go source runtime/internal/atomic.Xchg64. -// -//func swapUint64(ptr unsafe.Pointer, new uint64) (old uint64, sig int32) -TEXT ·swapUint64(SB), NOSPLIT, $0-28 - // Store 0 as the returned signal number. If we run to completion, - // this is the value the caller will see; if a signal is received, - // handleSwapUint64Fault will store a different value in this address. - MOVW $0, sig+24(FP) -again: - MOVD addr+0(FP), R0 - MOVD new+8(FP), R1 - LDAXR (R0), R2 - STLXR R1, (R0), R3 - CBNZ R3, again - MOVD R2, old+16(FP) - RET - -// handleCompareAndSwapUint32Fault returns the value stored in R1. Control is -// transferred to it when compareAndSwapUint32 below receives SIGSEGV or SIGBUS, -// with the signal number stored in R1. -// -// It must have the same frame configuration as compareAndSwapUint32 so that it -// can undo any potential call frame set up by the assembler. -TEXT handleCompareAndSwapUint32Fault(SB), NOSPLIT, $0-24 - MOVW R1, sig+20(FP) - RET - -// See the corresponding doc in safecopy_unsafe.go -// -// The code is derived from Go source runtime/internal/atomic.Cas. -// -//func compareAndSwapUint32(ptr unsafe.Pointer, old, new uint32) (prev uint32, sig int32) -TEXT ·compareAndSwapUint32(SB), NOSPLIT, $0-24 - // Store 0 as the returned signal number. If we run to completion, this is - // the value the caller will see; if a signal is received, - // handleCompareAndSwapUint32Fault will store a different value in this - // address. - MOVW $0, sig+20(FP) - - MOVD addr+0(FP), R0 - MOVW old+8(FP), R1 - MOVW new+12(FP), R2 -again: - LDAXRW (R0), R3 - CMPW R1, R3 - BNE done - STLXRW R2, (R0), R4 - CBNZ R4, again -done: - MOVW R3, prev+16(FP) - RET - -// handleLoadUint32Fault returns the value stored in DI. Control is transferred -// to it when LoadUint32 below receives SIGSEGV or SIGBUS, with the signal -// number stored in DI. -// -// It must have the same frame configuration as loadUint32 so that it can undo -// any potential call frame set up by the assembler. -TEXT handleLoadUint32Fault(SB), NOSPLIT, $0-16 - MOVW R1, sig+12(FP) - RET - -// loadUint32 atomically loads *addr and returns it. If a SIGSEGV or SIGBUS -// signal is received, the value returned is unspecified, and sig is the number -// of the signal that was received. -// -// Preconditions: addr must be aligned to a 4-byte boundary. -// -//func loadUint32(ptr unsafe.Pointer) (val uint32, sig int32) -TEXT ·loadUint32(SB), NOSPLIT, $0-16 - // Store 0 as the returned signal number. If we run to completion, - // this is the value the caller will see; if a signal is received, - // handleLoadUint32Fault will store a different value in this address. - MOVW $0, sig+12(FP) - - MOVD addr+0(FP), R0 - LDARW (R0), R1 - MOVW R1, val+8(FP) - RET diff --git a/pkg/sentry/platform/safecopy/memclr_amd64.s b/pkg/sentry/platform/safecopy/memclr_amd64.s deleted file mode 100644 index 64cf32f05..000000000 --- a/pkg/sentry/platform/safecopy/memclr_amd64.s +++ /dev/null @@ -1,147 +0,0 @@ -// Copyright 2014 The Go Authors. All rights reserved. -// Use of this source code is governed by a BSD-style -// license that can be found in the LICENSE file. - -#include "textflag.h" - -// handleMemclrFault returns (the value stored in AX, the value stored in DI). -// Control is transferred to it when memclr below receives SIGSEGV or SIGBUS, -// with the faulting address stored in AX and the signal number stored in DI. -// -// It must have the same frame configuration as memclr so that it can undo any -// potential call frame set up by the assembler. -TEXT handleMemclrFault(SB), NOSPLIT, $0-28 - MOVQ AX, addr+16(FP) - MOVL DI, sig+24(FP) - RET - -// memclr sets the n bytes following ptr to zeroes. If a SIGSEGV or SIGBUS -// signal is received during the write, it returns the address that caused the -// fault and the number of the signal that was received. Otherwise, it returns -// an unspecified address and a signal number of 0. -// -// Data is written in order, such that if a fault happens at address p, it is -// safe to assume that all data before p-maxRegisterSize has already been -// successfully written. -// -// The code is derived from runtime.memclrNoHeapPointers. -// -// func memclr(ptr unsafe.Pointer, n uintptr) (fault unsafe.Pointer, sig int32) -TEXT ·memclr(SB), NOSPLIT, $0-28 - // Store 0 as the returned signal number. If we run to completion, - // this is the value the caller will see; if a signal is received, - // handleMemclrFault will store a different value in this address. - MOVL $0, sig+24(FP) - - MOVQ ptr+0(FP), DI - MOVQ n+8(FP), BX - XORQ AX, AX - - // MOVOU seems always faster than REP STOSQ. -tail: - TESTQ BX, BX - JEQ _0 - CMPQ BX, $2 - JBE _1or2 - CMPQ BX, $4 - JBE _3or4 - CMPQ BX, $8 - JB _5through7 - JE _8 - CMPQ BX, $16 - JBE _9through16 - PXOR X0, X0 - CMPQ BX, $32 - JBE _17through32 - CMPQ BX, $64 - JBE _33through64 - CMPQ BX, $128 - JBE _65through128 - CMPQ BX, $256 - JBE _129through256 - // TODO: use branch table and BSR to make this just a single dispatch - // TODO: for really big clears, use MOVNTDQ, even without AVX2. - -loop: - MOVOU X0, 0(DI) - MOVOU X0, 16(DI) - MOVOU X0, 32(DI) - MOVOU X0, 48(DI) - MOVOU X0, 64(DI) - MOVOU X0, 80(DI) - MOVOU X0, 96(DI) - MOVOU X0, 112(DI) - MOVOU X0, 128(DI) - MOVOU X0, 144(DI) - MOVOU X0, 160(DI) - MOVOU X0, 176(DI) - MOVOU X0, 192(DI) - MOVOU X0, 208(DI) - MOVOU X0, 224(DI) - MOVOU X0, 240(DI) - SUBQ $256, BX - ADDQ $256, DI - CMPQ BX, $256 - JAE loop - JMP tail - -_1or2: - MOVB AX, (DI) - MOVB AX, -1(DI)(BX*1) - RET -_0: - RET -_3or4: - MOVW AX, (DI) - MOVW AX, -2(DI)(BX*1) - RET -_5through7: - MOVL AX, (DI) - MOVL AX, -4(DI)(BX*1) - RET -_8: - // We need a separate case for 8 to make sure we clear pointers atomically. - MOVQ AX, (DI) - RET -_9through16: - MOVQ AX, (DI) - MOVQ AX, -8(DI)(BX*1) - RET -_17through32: - MOVOU X0, (DI) - MOVOU X0, -16(DI)(BX*1) - RET -_33through64: - MOVOU X0, (DI) - MOVOU X0, 16(DI) - MOVOU X0, -32(DI)(BX*1) - MOVOU X0, -16(DI)(BX*1) - RET -_65through128: - MOVOU X0, (DI) - MOVOU X0, 16(DI) - MOVOU X0, 32(DI) - MOVOU X0, 48(DI) - MOVOU X0, -64(DI)(BX*1) - MOVOU X0, -48(DI)(BX*1) - MOVOU X0, -32(DI)(BX*1) - MOVOU X0, -16(DI)(BX*1) - RET -_129through256: - MOVOU X0, (DI) - MOVOU X0, 16(DI) - MOVOU X0, 32(DI) - MOVOU X0, 48(DI) - MOVOU X0, 64(DI) - MOVOU X0, 80(DI) - MOVOU X0, 96(DI) - MOVOU X0, 112(DI) - MOVOU X0, -128(DI)(BX*1) - MOVOU X0, -112(DI)(BX*1) - MOVOU X0, -96(DI)(BX*1) - MOVOU X0, -80(DI)(BX*1) - MOVOU X0, -64(DI)(BX*1) - MOVOU X0, -48(DI)(BX*1) - MOVOU X0, -32(DI)(BX*1) - MOVOU X0, -16(DI)(BX*1) - RET diff --git a/pkg/sentry/platform/safecopy/memclr_arm64.s b/pkg/sentry/platform/safecopy/memclr_arm64.s deleted file mode 100644 index 7361b9067..000000000 --- a/pkg/sentry/platform/safecopy/memclr_arm64.s +++ /dev/null @@ -1,74 +0,0 @@ -// Copyright 2014 The Go Authors. All rights reserved. -// Use of this source code is governed by a BSD-style -// license that can be found in the LICENSE file. - -#include "textflag.h" - -// handleMemclrFault returns (the value stored in R0, the value stored in R1). -// Control is transferred to it when memclr below receives SIGSEGV or SIGBUS, -// with the faulting address stored in R0 and the signal number stored in R1. -// -// It must have the same frame configuration as memclr so that it can undo any -// potential call frame set up by the assembler. -TEXT handleMemclrFault(SB), NOSPLIT, $0-28 - MOVD R0, addr+16(FP) - MOVW R1, sig+24(FP) - RET - -// See the corresponding doc in safecopy_unsafe.go -// -// The code is derived from runtime.memclrNoHeapPointers. -// -// func memclr(ptr unsafe.Pointer, n uintptr) (fault unsafe.Pointer, sig int32) -TEXT ·memclr(SB), NOSPLIT, $0-28 - // Store 0 as the returned signal number. If we run to completion, - // this is the value the caller will see; if a signal is received, - // handleMemclrFault will store a different value in this address. - MOVW $0, sig+24(FP) - MOVD ptr+0(FP), R0 - MOVD n+8(FP), R1 - - // If size is less than 16 bytes, use tail_zero to zero what remains - CMP $16, R1 - BLT tail_zero - // Get buffer offset into 16 byte aligned address for better performance - ANDS $15, R0, ZR - BNE unaligned_to_16 -aligned_to_16: - LSR $4, R1, R2 -zero_by_16: - STP.P (ZR, ZR), 16(R0) // Store pair with post index. - SUBS $1, R2, R2 - BNE zero_by_16 - ANDS $15, R1, R1 - BEQ end - - // Zero buffer with size=R1 < 16 -tail_zero: - TBZ $3, R1, tail_zero_4 - MOVD.P ZR, 8(R0) -tail_zero_4: - TBZ $2, R1, tail_zero_2 - MOVW.P ZR, 4(R0) -tail_zero_2: - TBZ $1, R1, tail_zero_1 - MOVH.P ZR, 2(R0) -tail_zero_1: - TBZ $0, R1, end - MOVB ZR, (R0) -end: - RET - -unaligned_to_16: - MOVD R0, R2 -head_loop: - MOVBU.P ZR, 1(R0) - ANDS $15, R0, ZR - BNE head_loop - // Adjust length for what remains - SUB R2, R0, R3 - SUB R3, R1 - // If size is less than 16 bytes, use tail_zero to zero what remains - CMP $16, R1 - BLT tail_zero - B aligned_to_16 diff --git a/pkg/sentry/platform/safecopy/memcpy_amd64.s b/pkg/sentry/platform/safecopy/memcpy_amd64.s deleted file mode 100644 index 129691d68..000000000 --- a/pkg/sentry/platform/safecopy/memcpy_amd64.s +++ /dev/null @@ -1,250 +0,0 @@ -// Copyright © 1994-1999 Lucent Technologies Inc. All rights reserved. -// Revisions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com). All rights reserved. -// Portions Copyright 2009 The Go Authors. All rights reserved. -// -// Permission is hereby granted, free of charge, to any person obtaining a copy -// of this software and associated documentation files (the "Software"), to deal -// in the Software without restriction, including without limitation the rights -// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell -// copies of the Software, and to permit persons to whom the Software is -// furnished to do so, subject to the following conditions: -// -// The above copyright notice and this permission notice shall be included in -// all copies or substantial portions of the Software. -// -// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR -// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, -// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE -// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER -// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, -// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN -// THE SOFTWARE. - -#include "textflag.h" - -// handleMemcpyFault returns (the value stored in AX, the value stored in DI). -// Control is transferred to it when memcpy below receives SIGSEGV or SIGBUS, -// with the faulting address stored in AX and the signal number stored in DI. -// -// It must have the same frame configuration as memcpy so that it can undo any -// potential call frame set up by the assembler. -TEXT handleMemcpyFault(SB), NOSPLIT, $0-36 - MOVQ AX, addr+24(FP) - MOVL DI, sig+32(FP) - RET - -// memcpy copies data from src to dst. If a SIGSEGV or SIGBUS signal is received -// during the copy, it returns the address that caused the fault and the number -// of the signal that was received. Otherwise, it returns an unspecified address -// and a signal number of 0. -// -// Data is copied in order, such that if a fault happens at address p, it is -// safe to assume that all data before p-maxRegisterSize has already been -// successfully copied. -// -// The code is derived from the forward copying part of runtime.memmove. -// -// func memcpy(dst, src unsafe.Pointer, n uintptr) (fault unsafe.Pointer, sig int32) -TEXT ·memcpy(SB), NOSPLIT, $0-36 - // Store 0 as the returned signal number. If we run to completion, - // this is the value the caller will see; if a signal is received, - // handleMemcpyFault will store a different value in this address. - MOVL $0, sig+32(FP) - - MOVQ to+0(FP), DI - MOVQ from+8(FP), SI - MOVQ n+16(FP), BX - - // REP instructions have a high startup cost, so we handle small sizes - // with some straightline code. The REP MOVSQ instruction is really fast - // for large sizes. The cutover is approximately 2K. -tail: - // move_129through256 or smaller work whether or not the source and the - // destination memory regions overlap because they load all data into - // registers before writing it back. move_256through2048 on the other - // hand can be used only when the memory regions don't overlap or the copy - // direction is forward. - TESTQ BX, BX - JEQ move_0 - CMPQ BX, $2 - JBE move_1or2 - CMPQ BX, $4 - JBE move_3or4 - CMPQ BX, $8 - JB move_5through7 - JE move_8 - CMPQ BX, $16 - JBE move_9through16 - CMPQ BX, $32 - JBE move_17through32 - CMPQ BX, $64 - JBE move_33through64 - CMPQ BX, $128 - JBE move_65through128 - CMPQ BX, $256 - JBE move_129through256 - // TODO: use branch table and BSR to make this just a single dispatch - -/* - * forward copy loop - */ - CMPQ BX, $2048 - JLS move_256through2048 - - // Check alignment - MOVL SI, AX - ORL DI, AX - TESTL $7, AX - JEQ fwdBy8 - - // Do 1 byte at a time - MOVQ BX, CX - REP; MOVSB - RET - -fwdBy8: - // Do 8 bytes at a time - MOVQ BX, CX - SHRQ $3, CX - ANDQ $7, BX - REP; MOVSQ - JMP tail - -move_1or2: - MOVB (SI), AX - MOVB AX, (DI) - MOVB -1(SI)(BX*1), CX - MOVB CX, -1(DI)(BX*1) - RET -move_0: - RET -move_3or4: - MOVW (SI), AX - MOVW AX, (DI) - MOVW -2(SI)(BX*1), CX - MOVW CX, -2(DI)(BX*1) - RET -move_5through7: - MOVL (SI), AX - MOVL AX, (DI) - MOVL -4(SI)(BX*1), CX - MOVL CX, -4(DI)(BX*1) - RET -move_8: - // We need a separate case for 8 to make sure we write pointers atomically. - MOVQ (SI), AX - MOVQ AX, (DI) - RET -move_9through16: - MOVQ (SI), AX - MOVQ AX, (DI) - MOVQ -8(SI)(BX*1), CX - MOVQ CX, -8(DI)(BX*1) - RET -move_17through32: - MOVOU (SI), X0 - MOVOU X0, (DI) - MOVOU -16(SI)(BX*1), X1 - MOVOU X1, -16(DI)(BX*1) - RET -move_33through64: - MOVOU (SI), X0 - MOVOU X0, (DI) - MOVOU 16(SI), X1 - MOVOU X1, 16(DI) - MOVOU -32(SI)(BX*1), X2 - MOVOU X2, -32(DI)(BX*1) - MOVOU -16(SI)(BX*1), X3 - MOVOU X3, -16(DI)(BX*1) - RET -move_65through128: - MOVOU (SI), X0 - MOVOU X0, (DI) - MOVOU 16(SI), X1 - MOVOU X1, 16(DI) - MOVOU 32(SI), X2 - MOVOU X2, 32(DI) - MOVOU 48(SI), X3 - MOVOU X3, 48(DI) - MOVOU -64(SI)(BX*1), X4 - MOVOU X4, -64(DI)(BX*1) - MOVOU -48(SI)(BX*1), X5 - MOVOU X5, -48(DI)(BX*1) - MOVOU -32(SI)(BX*1), X6 - MOVOU X6, -32(DI)(BX*1) - MOVOU -16(SI)(BX*1), X7 - MOVOU X7, -16(DI)(BX*1) - RET -move_129through256: - MOVOU (SI), X0 - MOVOU X0, (DI) - MOVOU 16(SI), X1 - MOVOU X1, 16(DI) - MOVOU 32(SI), X2 - MOVOU X2, 32(DI) - MOVOU 48(SI), X3 - MOVOU X3, 48(DI) - MOVOU 64(SI), X4 - MOVOU X4, 64(DI) - MOVOU 80(SI), X5 - MOVOU X5, 80(DI) - MOVOU 96(SI), X6 - MOVOU X6, 96(DI) - MOVOU 112(SI), X7 - MOVOU X7, 112(DI) - MOVOU -128(SI)(BX*1), X8 - MOVOU X8, -128(DI)(BX*1) - MOVOU -112(SI)(BX*1), X9 - MOVOU X9, -112(DI)(BX*1) - MOVOU -96(SI)(BX*1), X10 - MOVOU X10, -96(DI)(BX*1) - MOVOU -80(SI)(BX*1), X11 - MOVOU X11, -80(DI)(BX*1) - MOVOU -64(SI)(BX*1), X12 - MOVOU X12, -64(DI)(BX*1) - MOVOU -48(SI)(BX*1), X13 - MOVOU X13, -48(DI)(BX*1) - MOVOU -32(SI)(BX*1), X14 - MOVOU X14, -32(DI)(BX*1) - MOVOU -16(SI)(BX*1), X15 - MOVOU X15, -16(DI)(BX*1) - RET -move_256through2048: - SUBQ $256, BX - MOVOU (SI), X0 - MOVOU X0, (DI) - MOVOU 16(SI), X1 - MOVOU X1, 16(DI) - MOVOU 32(SI), X2 - MOVOU X2, 32(DI) - MOVOU 48(SI), X3 - MOVOU X3, 48(DI) - MOVOU 64(SI), X4 - MOVOU X4, 64(DI) - MOVOU 80(SI), X5 - MOVOU X5, 80(DI) - MOVOU 96(SI), X6 - MOVOU X6, 96(DI) - MOVOU 112(SI), X7 - MOVOU X7, 112(DI) - MOVOU 128(SI), X8 - MOVOU X8, 128(DI) - MOVOU 144(SI), X9 - MOVOU X9, 144(DI) - MOVOU 160(SI), X10 - MOVOU X10, 160(DI) - MOVOU 176(SI), X11 - MOVOU X11, 176(DI) - MOVOU 192(SI), X12 - MOVOU X12, 192(DI) - MOVOU 208(SI), X13 - MOVOU X13, 208(DI) - MOVOU 224(SI), X14 - MOVOU X14, 224(DI) - MOVOU 240(SI), X15 - MOVOU X15, 240(DI) - CMPQ BX, $256 - LEAQ 256(SI), SI - LEAQ 256(DI), DI - JGE move_256through2048 - JMP tail diff --git a/pkg/sentry/platform/safecopy/memcpy_arm64.s b/pkg/sentry/platform/safecopy/memcpy_arm64.s deleted file mode 100644 index e7e541565..000000000 --- a/pkg/sentry/platform/safecopy/memcpy_arm64.s +++ /dev/null @@ -1,78 +0,0 @@ -// Copyright 2014 The Go Authors. All rights reserved. -// Use of this source code is governed by a BSD-style -// license that can be found in the LICENSE file. - -#include "textflag.h" - -// handleMemcpyFault returns (the value stored in R0, the value stored in R1). -// Control is transferred to it when memcpy below receives SIGSEGV or SIGBUS, -// with the faulting address stored in R0 and the signal number stored in R1. -// -// It must have the same frame configuration as memcpy so that it can undo any -// potential call frame set up by the assembler. -TEXT handleMemcpyFault(SB), NOSPLIT, $0-36 - MOVD R0, addr+24(FP) - MOVW R1, sig+32(FP) - RET - -// memcpy copies data from src to dst. If a SIGSEGV or SIGBUS signal is received -// during the copy, it returns the address that caused the fault and the number -// of the signal that was received. Otherwise, it returns an unspecified address -// and a signal number of 0. -// -// Data is copied in order, such that if a fault happens at address p, it is -// safe to assume that all data before p-maxRegisterSize has already been -// successfully copied. -// -// The code is derived from the Go source runtime.memmove. -// -// func memcpy(dst, src unsafe.Pointer, n uintptr) (fault unsafe.Pointer, sig int32) -TEXT ·memcpy(SB), NOSPLIT, $-8-36 - // Store 0 as the returned signal number. If we run to completion, - // this is the value the caller will see; if a signal is received, - // handleMemcpyFault will store a different value in this address. - MOVW $0, sig+32(FP) - - MOVD to+0(FP), R3 - MOVD from+8(FP), R4 - MOVD n+16(FP), R5 - CMP $0, R5 - BNE check - RET - -check: - AND $~7, R5, R7 // R7 is N&~7. - SUB R7, R5, R6 // R6 is N&7. - - // Copying forward proceeds by copying R7/8 words then copying R6 bytes. - // R3 and R4 are advanced as we copy. - - // (There may be implementations of armv8 where copying by bytes until - // at least one of source or dest is word aligned is a worthwhile - // optimization, but the on the one tested so far (xgene) it did not - // make a significance difference.) - - CMP $0, R7 // Do we need to do any word-by-word copying? - BEQ noforwardlarge - ADD R3, R7, R9 // R9 points just past where we copy by word. - -forwardlargeloop: - MOVD.P 8(R4), R8 // R8 is just a scratch register. - MOVD.P R8, 8(R3) - CMP R3, R9 - BNE forwardlargeloop - -noforwardlarge: - CMP $0, R6 // Do we need to do any byte-by-byte copying? - BNE forwardtail - RET - -forwardtail: - ADD R3, R6, R9 // R9 points just past the destination memory. - -forwardtailloop: - MOVBU.P 1(R4), R8 - MOVBU.P R8, 1(R3) - CMP R3, R9 - BNE forwardtailloop - RET diff --git a/pkg/sentry/platform/safecopy/safecopy.go b/pkg/sentry/platform/safecopy/safecopy.go deleted file mode 100644 index 2fb7e5809..000000000 --- a/pkg/sentry/platform/safecopy/safecopy.go +++ /dev/null @@ -1,144 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -// Package safecopy provides an efficient implementation of functions to access -// memory that may result in SIGSEGV or SIGBUS being sent to the accessor. -package safecopy - -import ( - "fmt" - "reflect" - "runtime" - "syscall" - - "gvisor.dev/gvisor/pkg/syserror" -) - -// SegvError is returned when a safecopy function receives SIGSEGV. -type SegvError struct { - // Addr is the address at which the SIGSEGV occurred. - Addr uintptr -} - -// Error implements error.Error. -func (e SegvError) Error() string { - return fmt.Sprintf("SIGSEGV at %#x", e.Addr) -} - -// BusError is returned when a safecopy function receives SIGBUS. -type BusError struct { - // Addr is the address at which the SIGBUS occurred. - Addr uintptr -} - -// Error implements error.Error. -func (e BusError) Error() string { - return fmt.Sprintf("SIGBUS at %#x", e.Addr) -} - -// AlignmentError is returned when a safecopy function is passed an address -// that does not meet alignment requirements. -type AlignmentError struct { - // Addr is the invalid address. - Addr uintptr - - // Alignment is the required alignment. - Alignment uintptr -} - -// Error implements error.Error. -func (e AlignmentError) Error() string { - return fmt.Sprintf("address %#x is not aligned to a %d-byte boundary", e.Addr, e.Alignment) -} - -var ( - // The begin and end addresses below are for the functions that are - // checked by the signal handler. - memcpyBegin uintptr - memcpyEnd uintptr - memclrBegin uintptr - memclrEnd uintptr - swapUint32Begin uintptr - swapUint32End uintptr - swapUint64Begin uintptr - swapUint64End uintptr - compareAndSwapUint32Begin uintptr - compareAndSwapUint32End uintptr - loadUint32Begin uintptr - loadUint32End uintptr - - // savedSigSegVHandler is a pointer to the SIGSEGV handler that was - // configured before we replaced it with our own. We still call into it - // when we get a SIGSEGV that is not interesting to us. - savedSigSegVHandler uintptr - - // same a above, but for SIGBUS signals. - savedSigBusHandler uintptr -) - -// signalHandler is our replacement signal handler for SIGSEGV and SIGBUS -// signals. -func signalHandler() - -// FindEndAddress returns the end address (one byte beyond the last) of the -// function that contains the specified address (begin). -func FindEndAddress(begin uintptr) uintptr { - f := runtime.FuncForPC(begin) - if f != nil { - for p := begin; ; p++ { - g := runtime.FuncForPC(p) - if f != g { - return p - } - } - } - return begin -} - -// initializeAddresses initializes the addresses used by the signal handler. -func initializeAddresses() { - // The following functions are written in assembly language, so they won't - // be inlined by the existing compiler/linker. Tests will fail if this - // assumption is violated. - memcpyBegin = reflect.ValueOf(memcpy).Pointer() - memcpyEnd = FindEndAddress(memcpyBegin) - memclrBegin = reflect.ValueOf(memclr).Pointer() - memclrEnd = FindEndAddress(memclrBegin) - swapUint32Begin = reflect.ValueOf(swapUint32).Pointer() - swapUint32End = FindEndAddress(swapUint32Begin) - swapUint64Begin = reflect.ValueOf(swapUint64).Pointer() - swapUint64End = FindEndAddress(swapUint64Begin) - compareAndSwapUint32Begin = reflect.ValueOf(compareAndSwapUint32).Pointer() - compareAndSwapUint32End = FindEndAddress(compareAndSwapUint32Begin) - loadUint32Begin = reflect.ValueOf(loadUint32).Pointer() - loadUint32End = FindEndAddress(loadUint32Begin) -} - -func init() { - initializeAddresses() - if err := ReplaceSignalHandler(syscall.SIGSEGV, reflect.ValueOf(signalHandler).Pointer(), &savedSigSegVHandler); err != nil { - panic(fmt.Sprintf("Unable to set handler for SIGSEGV: %v", err)) - } - if err := ReplaceSignalHandler(syscall.SIGBUS, reflect.ValueOf(signalHandler).Pointer(), &savedSigBusHandler); err != nil { - panic(fmt.Sprintf("Unable to set handler for SIGBUS: %v", err)) - } - syserror.AddErrorUnwrapper(func(e error) (syscall.Errno, bool) { - switch e.(type) { - case SegvError, BusError, AlignmentError: - return syscall.EFAULT, true - default: - return 0, false - } - }) -} diff --git a/pkg/sentry/platform/safecopy/safecopy_test.go b/pkg/sentry/platform/safecopy/safecopy_test.go deleted file mode 100644 index 5818f7f9b..000000000 --- a/pkg/sentry/platform/safecopy/safecopy_test.go +++ /dev/null @@ -1,617 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -package safecopy - -import ( - "bytes" - "fmt" - "io/ioutil" - "math/rand" - "os" - "runtime/debug" - "syscall" - "testing" - "unsafe" -) - -// Size of a page in bytes. Cloned from usermem.PageSize to avoid a circular -// dependency. -const pageSize = 4096 - -func initRandom(b []byte) { - for i := range b { - b[i] = byte(rand.Intn(256)) - } -} - -func randBuf(size int) []byte { - b := make([]byte, size) - initRandom(b) - return b -} - -func TestCopyInSuccess(t *testing.T) { - // Test that CopyIn does not return an error when all pages are accessible. - const bufLen = 8192 - a := randBuf(bufLen) - b := make([]byte, bufLen) - - n, err := CopyIn(b, unsafe.Pointer(&a[0])) - if n != bufLen { - t.Errorf("Unexpected copy length, got %v, want %v", n, bufLen) - } - if err != nil { - t.Errorf("Unexpected error: %v", err) - } - if !bytes.Equal(a, b) { - t.Errorf("Buffers are not equal when they should be: %v %v", a, b) - } -} - -func TestCopyOutSuccess(t *testing.T) { - // Test that CopyOut does not return an error when all pages are - // accessible. - const bufLen = 8192 - a := randBuf(bufLen) - b := make([]byte, bufLen) - - n, err := CopyOut(unsafe.Pointer(&b[0]), a) - if n != bufLen { - t.Errorf("Unexpected copy length, got %v, want %v", n, bufLen) - } - if err != nil { - t.Errorf("Unexpected error: %v", err) - } - if !bytes.Equal(a, b) { - t.Errorf("Buffers are not equal when they should be: %v %v", a, b) - } -} - -func TestCopySuccess(t *testing.T) { - // Test that Copy does not return an error when all pages are accessible. - const bufLen = 8192 - a := randBuf(bufLen) - b := make([]byte, bufLen) - - n, err := Copy(unsafe.Pointer(&b[0]), unsafe.Pointer(&a[0]), bufLen) - if n != bufLen { - t.Errorf("Unexpected copy length, got %v, want %v", n, bufLen) - } - if err != nil { - t.Errorf("Unexpected error: %v", err) - } - if !bytes.Equal(a, b) { - t.Errorf("Buffers are not equal when they should be: %v %v", a, b) - } -} - -func TestZeroOutSuccess(t *testing.T) { - // Test that ZeroOut does not return an error when all pages are - // accessible. - const bufLen = 8192 - a := make([]byte, bufLen) - b := randBuf(bufLen) - - n, err := ZeroOut(unsafe.Pointer(&b[0]), bufLen) - if n != bufLen { - t.Errorf("Unexpected copy length, got %v, want %v", n, bufLen) - } - if err != nil { - t.Errorf("Unexpected error: %v", err) - } - if !bytes.Equal(a, b) { - t.Errorf("Buffers are not equal when they should be: %v %v", a, b) - } -} - -func TestSwapUint32Success(t *testing.T) { - // Test that SwapUint32 does not return an error when the page is - // accessible. - before := uint32(rand.Int31()) - after := uint32(rand.Int31()) - val := before - - old, err := SwapUint32(unsafe.Pointer(&val), after) - if err != nil { - t.Errorf("Unexpected error: %v", err) - } - if old != before { - t.Errorf("Unexpected old value: got %v, want %v", old, before) - } - if val != after { - t.Errorf("Unexpected new value: got %v, want %v", val, after) - } -} - -func TestSwapUint32AlignmentError(t *testing.T) { - // Test that SwapUint32 returns an AlignmentError when passed an unaligned - // address. - data := new(struct{ val uint64 }) - addr := uintptr(unsafe.Pointer(&data.val)) + 1 - want := AlignmentError{Addr: addr, Alignment: 4} - if _, err := SwapUint32(unsafe.Pointer(addr), 1); err != want { - t.Errorf("Unexpected error: got %v, want %v", err, want) - } -} - -func TestSwapUint64Success(t *testing.T) { - // Test that SwapUint64 does not return an error when the page is - // accessible. - before := uint64(rand.Int63()) - after := uint64(rand.Int63()) - // "The first word in ... an allocated struct or slice can be relied upon - // to be 64-bit aligned." - sync/atomic docs - data := new(struct{ val uint64 }) - data.val = before - - old, err := SwapUint64(unsafe.Pointer(&data.val), after) - if err != nil { - t.Errorf("Unexpected error: %v", err) - } - if old != before { - t.Errorf("Unexpected old value: got %v, want %v", old, before) - } - if data.val != after { - t.Errorf("Unexpected new value: got %v, want %v", data.val, after) - } -} - -func TestSwapUint64AlignmentError(t *testing.T) { - // Test that SwapUint64 returns an AlignmentError when passed an unaligned - // address. - data := new(struct{ val1, val2 uint64 }) - addr := uintptr(unsafe.Pointer(&data.val1)) + 1 - want := AlignmentError{Addr: addr, Alignment: 8} - if _, err := SwapUint64(unsafe.Pointer(addr), 1); err != want { - t.Errorf("Unexpected error: got %v, want %v", err, want) - } -} - -func TestCompareAndSwapUint32Success(t *testing.T) { - // Test that CompareAndSwapUint32 does not return an error when the page is - // accessible. - before := uint32(rand.Int31()) - after := uint32(rand.Int31()) - val := before - - old, err := CompareAndSwapUint32(unsafe.Pointer(&val), before, after) - if err != nil { - t.Errorf("Unexpected error: %v", err) - } - if old != before { - t.Errorf("Unexpected old value: got %v, want %v", old, before) - } - if val != after { - t.Errorf("Unexpected new value: got %v, want %v", val, after) - } -} - -func TestCompareAndSwapUint32AlignmentError(t *testing.T) { - // Test that CompareAndSwapUint32 returns an AlignmentError when passed an - // unaligned address. - data := new(struct{ val uint64 }) - addr := uintptr(unsafe.Pointer(&data.val)) + 1 - want := AlignmentError{Addr: addr, Alignment: 4} - if _, err := CompareAndSwapUint32(unsafe.Pointer(addr), 0, 1); err != want { - t.Errorf("Unexpected error: got %v, want %v", err, want) - } -} - -// withSegvErrorTestMapping calls fn with a two-page mapping. The first page -// contains random data, and the second page generates SIGSEGV when accessed. -func withSegvErrorTestMapping(t *testing.T, fn func(m []byte)) { - mapping, err := syscall.Mmap(-1, 0, 2*pageSize, syscall.PROT_READ|syscall.PROT_WRITE, syscall.MAP_ANONYMOUS|syscall.MAP_PRIVATE) - if err != nil { - t.Fatalf("Mmap failed: %v", err) - } - defer syscall.Munmap(mapping) - if err := syscall.Mprotect(mapping[pageSize:], syscall.PROT_NONE); err != nil { - t.Fatalf("Mprotect failed: %v", err) - } - initRandom(mapping[:pageSize]) - - fn(mapping) -} - -// withBusErrorTestMapping calls fn with a two-page mapping. The first page -// contains random data, and the second page generates SIGBUS when accessed. -func withBusErrorTestMapping(t *testing.T, fn func(m []byte)) { - f, err := ioutil.TempFile("", "sigbus_test") - if err != nil { - t.Fatalf("TempFile failed: %v", err) - } - defer f.Close() - if err := f.Truncate(pageSize); err != nil { - t.Fatalf("Truncate failed: %v", err) - } - mapping, err := syscall.Mmap(int(f.Fd()), 0, 2*pageSize, syscall.PROT_READ|syscall.PROT_WRITE, syscall.MAP_SHARED) - if err != nil { - t.Fatalf("Mmap failed: %v", err) - } - defer syscall.Munmap(mapping) - initRandom(mapping[:pageSize]) - - fn(mapping) -} - -func TestCopyInSegvError(t *testing.T) { - // Test that CopyIn returns a SegvError when reaching a page that signals - // SIGSEGV. - for bytesBeforeFault := 0; bytesBeforeFault <= 2*maxRegisterSize; bytesBeforeFault++ { - t.Run(fmt.Sprintf("starting copy %d bytes before SIGSEGV", bytesBeforeFault), func(t *testing.T) { - withSegvErrorTestMapping(t, func(mapping []byte) { - secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize - src := unsafe.Pointer(secondPage - uintptr(bytesBeforeFault)) - dst := randBuf(pageSize) - n, err := CopyIn(dst, src) - if n != bytesBeforeFault { - t.Errorf("Unexpected copy length: got %v, want %v", n, bytesBeforeFault) - } - if want := (SegvError{secondPage}); err != want { - t.Errorf("Unexpected error: got %v, want %v", err, want) - } - if got, want := dst[:bytesBeforeFault], mapping[pageSize-bytesBeforeFault:pageSize]; !bytes.Equal(got, want) { - t.Errorf("Buffers are not equal when they should be: %v %v", got, want) - } - }) - }) - } -} - -func TestCopyInBusError(t *testing.T) { - // Test that CopyIn returns a BusError when reaching a page that signals - // SIGBUS. - for bytesBeforeFault := 0; bytesBeforeFault <= 2*maxRegisterSize; bytesBeforeFault++ { - t.Run(fmt.Sprintf("starting copy %d bytes before SIGBUS", bytesBeforeFault), func(t *testing.T) { - withBusErrorTestMapping(t, func(mapping []byte) { - secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize - src := unsafe.Pointer(secondPage - uintptr(bytesBeforeFault)) - dst := randBuf(pageSize) - n, err := CopyIn(dst, src) - if n != bytesBeforeFault { - t.Errorf("Unexpected copy length: got %v, want %v", n, bytesBeforeFault) - } - if want := (BusError{secondPage}); err != want { - t.Errorf("Unexpected error: got %v, want %v", err, want) - } - if got, want := dst[:bytesBeforeFault], mapping[pageSize-bytesBeforeFault:pageSize]; !bytes.Equal(got, want) { - t.Errorf("Buffers are not equal when they should be: %v %v", got, want) - } - }) - }) - } -} - -func TestCopyOutSegvError(t *testing.T) { - // Test that CopyOut returns a SegvError when reaching a page that signals - // SIGSEGV. - for bytesBeforeFault := 0; bytesBeforeFault <= 2*maxRegisterSize; bytesBeforeFault++ { - t.Run(fmt.Sprintf("starting copy %d bytes before SIGSEGV", bytesBeforeFault), func(t *testing.T) { - withSegvErrorTestMapping(t, func(mapping []byte) { - secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize - dst := unsafe.Pointer(secondPage - uintptr(bytesBeforeFault)) - src := randBuf(pageSize) - n, err := CopyOut(dst, src) - if n != bytesBeforeFault { - t.Errorf("Unexpected copy length: got %v, want %v", n, bytesBeforeFault) - } - if want := (SegvError{secondPage}); err != want { - t.Errorf("Unexpected error: got %v, want %v", err, want) - } - if got, want := mapping[pageSize-bytesBeforeFault:pageSize], src[:bytesBeforeFault]; !bytes.Equal(got, want) { - t.Errorf("Buffers are not equal when they should be: %v %v", got, want) - } - }) - }) - } -} - -func TestCopyOutBusError(t *testing.T) { - // Test that CopyOut returns a BusError when reaching a page that signals - // SIGBUS. - for bytesBeforeFault := 0; bytesBeforeFault <= 2*maxRegisterSize; bytesBeforeFault++ { - t.Run(fmt.Sprintf("starting copy %d bytes before SIGSEGV", bytesBeforeFault), func(t *testing.T) { - withBusErrorTestMapping(t, func(mapping []byte) { - secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize - dst := unsafe.Pointer(secondPage - uintptr(bytesBeforeFault)) - src := randBuf(pageSize) - n, err := CopyOut(dst, src) - if n != bytesBeforeFault { - t.Errorf("Unexpected copy length: got %v, want %v", n, bytesBeforeFault) - } - if want := (BusError{secondPage}); err != want { - t.Errorf("Unexpected error: got %v, want %v", err, want) - } - if got, want := mapping[pageSize-bytesBeforeFault:pageSize], src[:bytesBeforeFault]; !bytes.Equal(got, want) { - t.Errorf("Buffers are not equal when they should be: %v %v", got, want) - } - }) - }) - } -} - -func TestCopySourceSegvError(t *testing.T) { - // Test that Copy returns a SegvError when copying from a page that signals - // SIGSEGV. - for bytesBeforeFault := 0; bytesBeforeFault <= 2*maxRegisterSize; bytesBeforeFault++ { - t.Run(fmt.Sprintf("starting copy %d bytes before SIGSEGV", bytesBeforeFault), func(t *testing.T) { - withSegvErrorTestMapping(t, func(mapping []byte) { - secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize - src := unsafe.Pointer(secondPage - uintptr(bytesBeforeFault)) - dst := randBuf(pageSize) - n, err := Copy(unsafe.Pointer(&dst[0]), src, pageSize) - if n != uintptr(bytesBeforeFault) { - t.Errorf("Unexpected copy length: got %v, want %v", n, bytesBeforeFault) - } - if want := (SegvError{secondPage}); err != want { - t.Errorf("Unexpected error: got %v, want %v", err, want) - } - if got, want := dst[:bytesBeforeFault], mapping[pageSize-bytesBeforeFault:pageSize]; !bytes.Equal(got, want) { - t.Errorf("Buffers are not equal when they should be: %v %v", got, want) - } - }) - }) - } -} - -func TestCopySourceBusError(t *testing.T) { - // Test that Copy returns a BusError when copying from a page that signals - // SIGBUS. - for bytesBeforeFault := 0; bytesBeforeFault <= 2*maxRegisterSize; bytesBeforeFault++ { - t.Run(fmt.Sprintf("starting copy %d bytes before SIGBUS", bytesBeforeFault), func(t *testing.T) { - withBusErrorTestMapping(t, func(mapping []byte) { - secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize - src := unsafe.Pointer(secondPage - uintptr(bytesBeforeFault)) - dst := randBuf(pageSize) - n, err := Copy(unsafe.Pointer(&dst[0]), src, pageSize) - if n != uintptr(bytesBeforeFault) { - t.Errorf("Unexpected copy length: got %v, want %v", n, bytesBeforeFault) - } - if want := (BusError{secondPage}); err != want { - t.Errorf("Unexpected error: got %v, want %v", err, want) - } - if got, want := dst[:bytesBeforeFault], mapping[pageSize-bytesBeforeFault:pageSize]; !bytes.Equal(got, want) { - t.Errorf("Buffers are not equal when they should be: %v %v", got, want) - } - }) - }) - } -} - -func TestCopyDestinationSegvError(t *testing.T) { - // Test that Copy returns a SegvError when copying to a page that signals - // SIGSEGV. - for bytesBeforeFault := 0; bytesBeforeFault <= 2*maxRegisterSize; bytesBeforeFault++ { - t.Run(fmt.Sprintf("starting copy %d bytes before SIGSEGV", bytesBeforeFault), func(t *testing.T) { - withSegvErrorTestMapping(t, func(mapping []byte) { - secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize - dst := unsafe.Pointer(secondPage - uintptr(bytesBeforeFault)) - src := randBuf(pageSize) - n, err := Copy(dst, unsafe.Pointer(&src[0]), pageSize) - if n != uintptr(bytesBeforeFault) { - t.Errorf("Unexpected copy length: got %v, want %v", n, bytesBeforeFault) - } - if want := (SegvError{secondPage}); err != want { - t.Errorf("Unexpected error: got %v, want %v", err, want) - } - if got, want := mapping[pageSize-bytesBeforeFault:pageSize], src[:bytesBeforeFault]; !bytes.Equal(got, want) { - t.Errorf("Buffers are not equal when they should be: %v %v", got, want) - } - }) - }) - } -} - -func TestCopyDestinationBusError(t *testing.T) { - // Test that Copy returns a BusError when copying to a page that signals - // SIGBUS. - for bytesBeforeFault := 0; bytesBeforeFault <= 2*maxRegisterSize; bytesBeforeFault++ { - t.Run(fmt.Sprintf("starting copy %d bytes before SIGBUS", bytesBeforeFault), func(t *testing.T) { - withBusErrorTestMapping(t, func(mapping []byte) { - secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize - dst := unsafe.Pointer(secondPage - uintptr(bytesBeforeFault)) - src := randBuf(pageSize) - n, err := Copy(dst, unsafe.Pointer(&src[0]), pageSize) - if n != uintptr(bytesBeforeFault) { - t.Errorf("Unexpected copy length: got %v, want %v", n, bytesBeforeFault) - } - if want := (BusError{secondPage}); err != want { - t.Errorf("Unexpected error: got %v, want %v", err, want) - } - if got, want := mapping[pageSize-bytesBeforeFault:pageSize], src[:bytesBeforeFault]; !bytes.Equal(got, want) { - t.Errorf("Buffers are not equal when they should be: %v %v", got, want) - } - }) - }) - } -} - -func TestZeroOutSegvError(t *testing.T) { - // Test that ZeroOut returns a SegvError when reaching a page that signals - // SIGSEGV. - for bytesBeforeFault := 0; bytesBeforeFault <= 2*maxRegisterSize; bytesBeforeFault++ { - t.Run(fmt.Sprintf("starting write %d bytes before SIGSEGV", bytesBeforeFault), func(t *testing.T) { - withSegvErrorTestMapping(t, func(mapping []byte) { - secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize - dst := unsafe.Pointer(secondPage - uintptr(bytesBeforeFault)) - n, err := ZeroOut(dst, pageSize) - if n != uintptr(bytesBeforeFault) { - t.Errorf("Unexpected write length: got %v, want %v", n, bytesBeforeFault) - } - if want := (SegvError{secondPage}); err != want { - t.Errorf("Unexpected error: got %v, want %v", err, want) - } - if got, want := mapping[pageSize-bytesBeforeFault:pageSize], make([]byte, bytesBeforeFault); !bytes.Equal(got, want) { - t.Errorf("Non-zero bytes in written part of mapping: %v", got) - } - }) - }) - } -} - -func TestZeroOutBusError(t *testing.T) { - // Test that ZeroOut returns a BusError when reaching a page that signals - // SIGBUS. - for bytesBeforeFault := 0; bytesBeforeFault <= 2*maxRegisterSize; bytesBeforeFault++ { - t.Run(fmt.Sprintf("starting write %d bytes before SIGBUS", bytesBeforeFault), func(t *testing.T) { - withBusErrorTestMapping(t, func(mapping []byte) { - secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize - dst := unsafe.Pointer(secondPage - uintptr(bytesBeforeFault)) - n, err := ZeroOut(dst, pageSize) - if n != uintptr(bytesBeforeFault) { - t.Errorf("Unexpected write length: got %v, want %v", n, bytesBeforeFault) - } - if want := (BusError{secondPage}); err != want { - t.Errorf("Unexpected error: got %v, want %v", err, want) - } - if got, want := mapping[pageSize-bytesBeforeFault:pageSize], make([]byte, bytesBeforeFault); !bytes.Equal(got, want) { - t.Errorf("Non-zero bytes in written part of mapping: %v", got) - } - }) - }) - } -} - -func TestSwapUint32SegvError(t *testing.T) { - // Test that SwapUint32 returns a SegvError when reaching a page that - // signals SIGSEGV. - withSegvErrorTestMapping(t, func(mapping []byte) { - secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize - _, err := SwapUint32(unsafe.Pointer(secondPage), 1) - if want := (SegvError{secondPage}); err != want { - t.Errorf("Unexpected error: got %v, want %v", err, want) - } - }) -} - -func TestSwapUint32BusError(t *testing.T) { - // Test that SwapUint32 returns a BusError when reaching a page that - // signals SIGBUS. - withBusErrorTestMapping(t, func(mapping []byte) { - secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize - _, err := SwapUint32(unsafe.Pointer(secondPage), 1) - if want := (BusError{secondPage}); err != want { - t.Errorf("Unexpected error: got %v, want %v", err, want) - } - }) -} - -func TestSwapUint64SegvError(t *testing.T) { - // Test that SwapUint64 returns a SegvError when reaching a page that - // signals SIGSEGV. - withSegvErrorTestMapping(t, func(mapping []byte) { - secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize - _, err := SwapUint64(unsafe.Pointer(secondPage), 1) - if want := (SegvError{secondPage}); err != want { - t.Errorf("Unexpected error: got %v, want %v", err, want) - } - }) -} - -func TestSwapUint64BusError(t *testing.T) { - // Test that SwapUint64 returns a BusError when reaching a page that - // signals SIGBUS. - withBusErrorTestMapping(t, func(mapping []byte) { - secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize - _, err := SwapUint64(unsafe.Pointer(secondPage), 1) - if want := (BusError{secondPage}); err != want { - t.Errorf("Unexpected error: got %v, want %v", err, want) - } - }) -} - -func TestCompareAndSwapUint32SegvError(t *testing.T) { - // Test that CompareAndSwapUint32 returns a SegvError when reaching a page - // that signals SIGSEGV. - withSegvErrorTestMapping(t, func(mapping []byte) { - secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize - _, err := CompareAndSwapUint32(unsafe.Pointer(secondPage), 0, 1) - if want := (SegvError{secondPage}); err != want { - t.Errorf("Unexpected error: got %v, want %v", err, want) - } - }) -} - -func TestCompareAndSwapUint32BusError(t *testing.T) { - // Test that CompareAndSwapUint32 returns a BusError when reaching a page - // that signals SIGBUS. - withBusErrorTestMapping(t, func(mapping []byte) { - secondPage := uintptr(unsafe.Pointer(&mapping[0])) + pageSize - _, err := CompareAndSwapUint32(unsafe.Pointer(secondPage), 0, 1) - if want := (BusError{secondPage}); err != want { - t.Errorf("Unexpected error: got %v, want %v", err, want) - } - }) -} - -func testCopy(dst, src []byte) (panicked bool) { - defer func() { - if r := recover(); r != nil { - panicked = true - } - }() - debug.SetPanicOnFault(true) - copy(dst, src) - return -} - -func TestSegVOnMemmove(t *testing.T) { - // Test that SIGSEGVs received by runtime.memmove when *not* doing - // CopyIn or CopyOut work gets propagated to the runtime. - const bufLen = pageSize - a, err := syscall.Mmap(-1, 0, bufLen, syscall.PROT_NONE, syscall.MAP_ANON|syscall.MAP_PRIVATE) - if err != nil { - t.Fatalf("Mmap failed: %v", err) - - } - defer syscall.Munmap(a) - b := randBuf(bufLen) - - if !testCopy(b, a) { - t.Fatalf("testCopy didn't panic when it should have") - } - - if !testCopy(a, b) { - t.Fatalf("testCopy didn't panic when it should have") - } -} - -func TestSigbusOnMemmove(t *testing.T) { - // Test that SIGBUS received by runtime.memmove when *not* doing - // CopyIn or CopyOut work gets propagated to the runtime. - const bufLen = pageSize - f, err := ioutil.TempFile("", "sigbus_test") - if err != nil { - t.Fatalf("TempFile failed: %v", err) - } - os.Remove(f.Name()) - defer f.Close() - - a, err := syscall.Mmap(int(f.Fd()), 0, bufLen, syscall.PROT_READ|syscall.PROT_WRITE, syscall.MAP_SHARED) - if err != nil { - t.Fatalf("Mmap failed: %v", err) - - } - defer syscall.Munmap(a) - b := randBuf(bufLen) - - if !testCopy(b, a) { - t.Fatalf("testCopy didn't panic when it should have") - } - - if !testCopy(a, b) { - t.Fatalf("testCopy didn't panic when it should have") - } -} diff --git a/pkg/sentry/platform/safecopy/safecopy_unsafe.go b/pkg/sentry/platform/safecopy/safecopy_unsafe.go deleted file mode 100644 index eef028e68..000000000 --- a/pkg/sentry/platform/safecopy/safecopy_unsafe.go +++ /dev/null @@ -1,335 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -package safecopy - -import ( - "fmt" - "syscall" - "unsafe" -) - -// maxRegisterSize is the maximum register size used in memcpy and memclr. It -// is used to decide by how much to rewind the copy (for memcpy) or zeroing -// (for memclr) before proceeding. -const maxRegisterSize = 16 - -// memcpy copies data from src to dst. If a SIGSEGV or SIGBUS signal is received -// during the copy, it returns the address that caused the fault and the number -// of the signal that was received. Otherwise, it returns an unspecified address -// and a signal number of 0. -// -// Data is copied in order, such that if a fault happens at address p, it is -// safe to assume that all data before p-maxRegisterSize has already been -// successfully copied. -// -//go:noescape -func memcpy(dst, src unsafe.Pointer, n uintptr) (fault unsafe.Pointer, sig int32) - -// memclr sets the n bytes following ptr to zeroes. If a SIGSEGV or SIGBUS -// signal is received during the write, it returns the address that caused the -// fault and the number of the signal that was received. Otherwise, it returns -// an unspecified address and a signal number of 0. -// -// Data is written in order, such that if a fault happens at address p, it is -// safe to assume that all data before p-maxRegisterSize has already been -// successfully written. -// -//go:noescape -func memclr(ptr unsafe.Pointer, n uintptr) (fault unsafe.Pointer, sig int32) - -// swapUint32 atomically stores new into *ptr and returns (the previous *ptr -// value, 0). If a SIGSEGV or SIGBUS signal is received during the swap, the -// value of old is unspecified, and sig is the number of the signal that was -// received. -// -// Preconditions: ptr must be aligned to a 4-byte boundary. -// -//go:noescape -func swapUint32(ptr unsafe.Pointer, new uint32) (old uint32, sig int32) - -// swapUint64 atomically stores new into *ptr and returns (the previous *ptr -// value, 0). If a SIGSEGV or SIGBUS signal is received during the swap, the -// value of old is unspecified, and sig is the number of the signal that was -// received. -// -// Preconditions: ptr must be aligned to a 8-byte boundary. -// -//go:noescape -func swapUint64(ptr unsafe.Pointer, new uint64) (old uint64, sig int32) - -// compareAndSwapUint32 is like sync/atomic.CompareAndSwapUint32, but returns -// (the value previously stored at ptr, 0). If a SIGSEGV or SIGBUS signal is -// received during the operation, the value of prev is unspecified, and sig is -// the number of the signal that was received. -// -// Preconditions: ptr must be aligned to a 4-byte boundary. -// -//go:noescape -func compareAndSwapUint32(ptr unsafe.Pointer, old, new uint32) (prev uint32, sig int32) - -// LoadUint32 is like sync/atomic.LoadUint32, but operates with user memory. It -// may fail with SIGSEGV or SIGBUS if it is received while reading from ptr. -// -// Preconditions: ptr must be aligned to a 4-byte boundary. -// -//go:noescape -func loadUint32(ptr unsafe.Pointer) (val uint32, sig int32) - -// CopyIn copies len(dst) bytes from src to dst. It returns the number of bytes -// copied and an error if SIGSEGV or SIGBUS is received while reading from src. -func CopyIn(dst []byte, src unsafe.Pointer) (int, error) { - toCopy := uintptr(len(dst)) - if len(dst) == 0 { - return 0, nil - } - - fault, sig := memcpy(unsafe.Pointer(&dst[0]), src, toCopy) - if sig == 0 { - return len(dst), nil - } - - faultN, srcN := uintptr(fault), uintptr(src) - if faultN < srcN || faultN >= srcN+toCopy { - panic(fmt.Sprintf("CopyIn raised signal %d at %#x, which is outside source [%#x, %#x)", sig, faultN, srcN, srcN+toCopy)) - } - - // memcpy might have ended the copy up to maxRegisterSize bytes before - // fault, if an instruction caused a memory access that straddled two - // pages, and the second one faulted. Try to copy up to the fault. - var done int - if faultN-srcN > maxRegisterSize { - done = int(faultN - srcN - maxRegisterSize) - } - n, err := CopyIn(dst[done:int(faultN-srcN)], unsafe.Pointer(srcN+uintptr(done))) - done += n - if err != nil { - return done, err - } - return done, errorFromFaultSignal(fault, sig) -} - -// CopyOut copies len(src) bytes from src to dst. If returns the number of -// bytes done and an error if SIGSEGV or SIGBUS is received while writing to -// dst. -func CopyOut(dst unsafe.Pointer, src []byte) (int, error) { - toCopy := uintptr(len(src)) - if toCopy == 0 { - return 0, nil - } - - fault, sig := memcpy(dst, unsafe.Pointer(&src[0]), toCopy) - if sig == 0 { - return len(src), nil - } - - faultN, dstN := uintptr(fault), uintptr(dst) - if faultN < dstN || faultN >= dstN+toCopy { - panic(fmt.Sprintf("CopyOut raised signal %d at %#x, which is outside destination [%#x, %#x)", sig, faultN, dstN, dstN+toCopy)) - } - - // memcpy might have ended the copy up to maxRegisterSize bytes before - // fault, if an instruction caused a memory access that straddled two - // pages, and the second one faulted. Try to copy up to the fault. - var done int - if faultN-dstN > maxRegisterSize { - done = int(faultN - dstN - maxRegisterSize) - } - n, err := CopyOut(unsafe.Pointer(dstN+uintptr(done)), src[done:int(faultN-dstN)]) - done += n - if err != nil { - return done, err - } - return done, errorFromFaultSignal(fault, sig) -} - -// Copy copies toCopy bytes from src to dst. It returns the number of bytes -// copied and an error if SIGSEGV or SIGBUS is received while reading from src -// or writing to dst. -// -// Data is copied in order; if [src, src+toCopy) and [dst, dst+toCopy) overlap, -// the resulting contents of dst are unspecified. -func Copy(dst, src unsafe.Pointer, toCopy uintptr) (uintptr, error) { - if toCopy == 0 { - return 0, nil - } - - fault, sig := memcpy(dst, src, toCopy) - if sig == 0 { - return toCopy, nil - } - - // Did the fault occur while reading from src or writing to dst? - faultN, srcN, dstN := uintptr(fault), uintptr(src), uintptr(dst) - faultAfterSrc := ^uintptr(0) - if faultN >= srcN { - faultAfterSrc = faultN - srcN - } - faultAfterDst := ^uintptr(0) - if faultN >= dstN { - faultAfterDst = faultN - dstN - } - if faultAfterSrc >= toCopy && faultAfterDst >= toCopy { - panic(fmt.Sprintf("Copy raised signal %d at %#x, which is outside source [%#x, %#x) and destination [%#x, %#x)", sig, faultN, srcN, srcN+toCopy, dstN, dstN+toCopy)) - } - faultedAfter := faultAfterSrc - if faultedAfter > faultAfterDst { - faultedAfter = faultAfterDst - } - - // memcpy might have ended the copy up to maxRegisterSize bytes before - // fault, if an instruction caused a memory access that straddled two - // pages, and the second one faulted. Try to copy up to the fault. - var done uintptr - if faultedAfter > maxRegisterSize { - done = faultedAfter - maxRegisterSize - } - n, err := Copy(unsafe.Pointer(dstN+done), unsafe.Pointer(srcN+done), faultedAfter-done) - done += n - if err != nil { - return done, err - } - return done, errorFromFaultSignal(fault, sig) -} - -// ZeroOut writes toZero zero bytes to dst. It returns the number of bytes -// written and an error if SIGSEGV or SIGBUS is received while writing to dst. -func ZeroOut(dst unsafe.Pointer, toZero uintptr) (uintptr, error) { - if toZero == 0 { - return 0, nil - } - - fault, sig := memclr(dst, toZero) - if sig == 0 { - return toZero, nil - } - - faultN, dstN := uintptr(fault), uintptr(dst) - if faultN < dstN || faultN >= dstN+toZero { - panic(fmt.Sprintf("ZeroOut raised signal %d at %#x, which is outside destination [%#x, %#x)", sig, faultN, dstN, dstN+toZero)) - } - - // memclr might have ended the write up to maxRegisterSize bytes before - // fault, if an instruction caused a memory access that straddled two - // pages, and the second one faulted. Try to write up to the fault. - var done uintptr - if faultN-dstN > maxRegisterSize { - done = faultN - dstN - maxRegisterSize - } - n, err := ZeroOut(unsafe.Pointer(dstN+done), faultN-dstN-done) - done += n - if err != nil { - return done, err - } - return done, errorFromFaultSignal(fault, sig) -} - -// SwapUint32 is equivalent to sync/atomic.SwapUint32, except that it returns -// an error if SIGSEGV or SIGBUS is received while accessing ptr, or if ptr is -// not aligned to a 4-byte boundary. -func SwapUint32(ptr unsafe.Pointer, new uint32) (uint32, error) { - if addr := uintptr(ptr); addr&3 != 0 { - return 0, AlignmentError{addr, 4} - } - old, sig := swapUint32(ptr, new) - return old, errorFromFaultSignal(ptr, sig) -} - -// SwapUint64 is equivalent to sync/atomic.SwapUint64, except that it returns -// an error if SIGSEGV or SIGBUS is received while accessing ptr, or if ptr is -// not aligned to an 8-byte boundary. -func SwapUint64(ptr unsafe.Pointer, new uint64) (uint64, error) { - if addr := uintptr(ptr); addr&7 != 0 { - return 0, AlignmentError{addr, 8} - } - old, sig := swapUint64(ptr, new) - return old, errorFromFaultSignal(ptr, sig) -} - -// CompareAndSwapUint32 is equivalent to atomicbitops.CompareAndSwapUint32, -// except that it returns an error if SIGSEGV or SIGBUS is received while -// accessing ptr, or if ptr is not aligned to a 4-byte boundary. -func CompareAndSwapUint32(ptr unsafe.Pointer, old, new uint32) (uint32, error) { - if addr := uintptr(ptr); addr&3 != 0 { - return 0, AlignmentError{addr, 4} - } - prev, sig := compareAndSwapUint32(ptr, old, new) - return prev, errorFromFaultSignal(ptr, sig) -} - -// LoadUint32 is like sync/atomic.LoadUint32, but operates with user memory. It -// may fail with SIGSEGV or SIGBUS if it is received while reading from ptr. -// -// Preconditions: ptr must be aligned to a 4-byte boundary. -func LoadUint32(ptr unsafe.Pointer) (uint32, error) { - if addr := uintptr(ptr); addr&3 != 0 { - return 0, AlignmentError{addr, 4} - } - val, sig := loadUint32(ptr) - return val, errorFromFaultSignal(ptr, sig) -} - -func errorFromFaultSignal(addr unsafe.Pointer, sig int32) error { - switch sig { - case 0: - return nil - case int32(syscall.SIGSEGV): - return SegvError{uintptr(addr)} - case int32(syscall.SIGBUS): - return BusError{uintptr(addr)} - default: - panic(fmt.Sprintf("safecopy got unexpected signal %d at address %#x", sig, addr)) - } -} - -// ReplaceSignalHandler replaces the existing signal handler for the provided -// signal with the one that handles faults in safecopy-protected functions. -// -// It stores the value of the previously set handler in previous. -// -// This function will be called on initialization in order to install safecopy -// handlers for appropriate signals. These handlers will call the previous -// handler however, and if this is function is being used externally then the -// same courtesy is expected. -func ReplaceSignalHandler(sig syscall.Signal, handler uintptr, previous *uintptr) error { - var sa struct { - handler uintptr - flags uint64 - restorer uintptr - mask uint64 - } - const maskLen = 8 - - // Get the existing signal handler information, and save the current - // handler. Once we replace it, we will use this pointer to fall back to - // it when we receive other signals. - if _, _, e := syscall.RawSyscall6(syscall.SYS_RT_SIGACTION, uintptr(sig), 0, uintptr(unsafe.Pointer(&sa)), maskLen, 0, 0); e != 0 { - return e - } - - // Fail if there isn't a previous handler. - if sa.handler == 0 { - return fmt.Errorf("previous handler for signal %x isn't set", sig) - } - - *previous = sa.handler - - // Install our own handler. - sa.handler = handler - if _, _, e := syscall.RawSyscall6(syscall.SYS_RT_SIGACTION, uintptr(sig), uintptr(unsafe.Pointer(&sa)), 0, maskLen, 0, 0); e != 0 { - return e - } - - return nil -} diff --git a/pkg/sentry/platform/safecopy/sighandler_amd64.s b/pkg/sentry/platform/safecopy/sighandler_amd64.s deleted file mode 100644 index 475ae48e9..000000000 --- a/pkg/sentry/platform/safecopy/sighandler_amd64.s +++ /dev/null @@ -1,133 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -#include "textflag.h" - -// The signals handled by sigHandler. -#define SIGBUS 7 -#define SIGSEGV 11 - -// Offsets to the registers in context->uc_mcontext.gregs[]. -#define REG_RDI 0x68 -#define REG_RAX 0x90 -#define REG_IP 0xa8 - -// Offset to the si_addr field of siginfo. -#define SI_CODE 0x08 -#define SI_ADDR 0x10 - -// signalHandler is the signal handler for SIGSEGV and SIGBUS signals. It must -// not be set up as a handler to any other signals. -// -// If the instruction causing the signal is within a safecopy-protected -// function, the signal is handled such that execution resumes in the -// appropriate fault handling stub with AX containing the faulting address and -// DI containing the signal number. Otherwise control is transferred to the -// previously configured signal handler (savedSigSegvHandler or -// savedSigBusHandler). -// -// This function cannot be written in go because it runs whenever a signal is -// received by the thread (preempting whatever was running), which includes when -// garbage collector has stopped or isn't expecting any interactions (like -// barriers). -// -// The arguments are the following: -// DI - The signal number. -// SI - Pointer to siginfo_t structure. -// DX - Pointer to ucontext structure. -TEXT ·signalHandler(SB),NOSPLIT,$0 - // Check if the signal is from the kernel. - MOVQ $0x0, CX - CMPL CX, SI_CODE(SI) - JGE original_handler - - // Check if RIP is within the area we care about. - MOVQ REG_IP(DX), CX - CMPQ CX, ·memcpyBegin(SB) - JB not_memcpy - CMPQ CX, ·memcpyEnd(SB) - JAE not_memcpy - - // Modify the context such that execution will resume in the fault - // handler. - LEAQ handleMemcpyFault(SB), CX - JMP handle_fault - -not_memcpy: - CMPQ CX, ·memclrBegin(SB) - JB not_memclr - CMPQ CX, ·memclrEnd(SB) - JAE not_memclr - - LEAQ handleMemclrFault(SB), CX - JMP handle_fault - -not_memclr: - CMPQ CX, ·swapUint32Begin(SB) - JB not_swapuint32 - CMPQ CX, ·swapUint32End(SB) - JAE not_swapuint32 - - LEAQ handleSwapUint32Fault(SB), CX - JMP handle_fault - -not_swapuint32: - CMPQ CX, ·swapUint64Begin(SB) - JB not_swapuint64 - CMPQ CX, ·swapUint64End(SB) - JAE not_swapuint64 - - LEAQ handleSwapUint64Fault(SB), CX - JMP handle_fault - -not_swapuint64: - CMPQ CX, ·compareAndSwapUint32Begin(SB) - JB not_casuint32 - CMPQ CX, ·compareAndSwapUint32End(SB) - JAE not_casuint32 - - LEAQ handleCompareAndSwapUint32Fault(SB), CX - JMP handle_fault - -not_casuint32: - CMPQ CX, ·loadUint32Begin(SB) - JB not_loaduint32 - CMPQ CX, ·loadUint32End(SB) - JAE not_loaduint32 - - LEAQ handleLoadUint32Fault(SB), CX - JMP handle_fault - -not_loaduint32: -original_handler: - // Jump to the previous signal handler, which is likely the golang one. - XORQ CX, CX - MOVQ ·savedSigBusHandler(SB), AX - CMPL DI, $SIGSEGV - CMOVQEQ ·savedSigSegVHandler(SB), AX - JMP AX - -handle_fault: - // Entered with the address of the fault handler in RCX; store it in - // RIP. - MOVQ CX, REG_IP(DX) - - // Store the faulting address in RAX. - MOVQ SI_ADDR(SI), CX - MOVQ CX, REG_RAX(DX) - - // Store the signal number in EDI. - MOVL DI, REG_RDI(DX) - - RET diff --git a/pkg/sentry/platform/safecopy/sighandler_arm64.s b/pkg/sentry/platform/safecopy/sighandler_arm64.s deleted file mode 100644 index 53e4ac2c1..000000000 --- a/pkg/sentry/platform/safecopy/sighandler_arm64.s +++ /dev/null @@ -1,143 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -#include "textflag.h" - -// The signals handled by sigHandler. -#define SIGBUS 7 -#define SIGSEGV 11 - -// Offsets to the registers in context->uc_mcontext.gregs[]. -#define REG_R0 0xB8 -#define REG_R1 0xC0 -#define REG_PC 0x1B8 - -// Offset to the si_addr field of siginfo. -#define SI_CODE 0x08 -#define SI_ADDR 0x10 - -// signalHandler is the signal handler for SIGSEGV and SIGBUS signals. It must -// not be set up as a handler to any other signals. -// -// If the instruction causing the signal is within a safecopy-protected -// function, the signal is handled such that execution resumes in the -// appropriate fault handling stub with R0 containing the faulting address and -// R1 containing the signal number. Otherwise control is transferred to the -// previously configured signal handler (savedSigSegvHandler or -// savedSigBusHandler). -// -// This function cannot be written in go because it runs whenever a signal is -// received by the thread (preempting whatever was running), which includes when -// garbage collector has stopped or isn't expecting any interactions (like -// barriers). -// -// The arguments are the following: -// R0 - The signal number. -// R1 - Pointer to siginfo_t structure. -// R2 - Pointer to ucontext structure. -TEXT ·signalHandler(SB),NOSPLIT,$0 - // Check if the signal is from the kernel, si_code > 0 means a kernel signal. - MOVD SI_CODE(R1), R7 - CMPW $0x0, R7 - BLE original_handler - - // Check if PC is within the area we care about. - MOVD REG_PC(R2), R7 - MOVD ·memcpyBegin(SB), R8 - CMP R8, R7 - BLO not_memcpy - MOVD ·memcpyEnd(SB), R8 - CMP R8, R7 - BHS not_memcpy - - // Modify the context such that execution will resume in the fault handler. - MOVD $handleMemcpyFault(SB), R7 - B handle_fault - -not_memcpy: - MOVD ·memclrBegin(SB), R8 - CMP R8, R7 - BLO not_memclr - MOVD ·memclrEnd(SB), R8 - CMP R8, R7 - BHS not_memclr - - MOVD $handleMemclrFault(SB), R7 - B handle_fault - -not_memclr: - MOVD ·swapUint32Begin(SB), R8 - CMP R8, R7 - BLO not_swapuint32 - MOVD ·swapUint32End(SB), R8 - CMP R8, R7 - BHS not_swapuint32 - - MOVD $handleSwapUint32Fault(SB), R7 - B handle_fault - -not_swapuint32: - MOVD ·swapUint64Begin(SB), R8 - CMP R8, R7 - BLO not_swapuint64 - MOVD ·swapUint64End(SB), R8 - CMP R8, R7 - BHS not_swapuint64 - - MOVD $handleSwapUint64Fault(SB), R7 - B handle_fault - -not_swapuint64: - MOVD ·compareAndSwapUint32Begin(SB), R8 - CMP R8, R7 - BLO not_casuint32 - MOVD ·compareAndSwapUint32End(SB), R8 - CMP R8, R7 - BHS not_casuint32 - - MOVD $handleCompareAndSwapUint32Fault(SB), R7 - B handle_fault - -not_casuint32: - MOVD ·loadUint32Begin(SB), R8 - CMP R8, R7 - BLO not_loaduint32 - MOVD ·loadUint32End(SB), R8 - CMP R8, R7 - BHS not_loaduint32 - - MOVD $handleLoadUint32Fault(SB), R7 - B handle_fault - -not_loaduint32: -original_handler: - // Jump to the previous signal handler, which is likely the golang one. - MOVD ·savedSigBusHandler(SB), R7 - MOVD ·savedSigSegVHandler(SB), R8 - CMPW $SIGSEGV, R0 - CSEL EQ, R8, R7, R7 - B (R7) - -handle_fault: - // Entered with the address of the fault handler in R7; store it in PC. - MOVD R7, REG_PC(R2) - - // Store the faulting address in R0. - MOVD SI_ADDR(R1), R7 - MOVD R7, REG_R0(R2) - - // Store the signal number in R1. - MOVW R0, REG_R1(R2) - - RET diff --git a/pkg/sentry/safemem/BUILD b/pkg/sentry/safemem/BUILD deleted file mode 100644 index 3ab76da97..000000000 --- a/pkg/sentry/safemem/BUILD +++ /dev/null @@ -1,27 +0,0 @@ -load("//tools:defs.bzl", "go_library", "go_test") - -package(licenses = ["notice"]) - -go_library( - name = "safemem", - srcs = [ - "block_unsafe.go", - "io.go", - "safemem.go", - "seq_unsafe.go", - ], - visibility = ["//pkg/sentry:internal"], - deps = [ - "//pkg/sentry/platform/safecopy", - ], -) - -go_test( - name = "safemem_test", - size = "small", - srcs = [ - "io_test.go", - "seq_test.go", - ], - library = ":safemem", -) diff --git a/pkg/sentry/safemem/block_unsafe.go b/pkg/sentry/safemem/block_unsafe.go deleted file mode 100644 index 6f03c94bf..000000000 --- a/pkg/sentry/safemem/block_unsafe.go +++ /dev/null @@ -1,279 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -package safemem - -import ( - "fmt" - "reflect" - "unsafe" - - "gvisor.dev/gvisor/pkg/sentry/platform/safecopy" -) - -// A Block is a range of contiguous bytes, similar to []byte but with the -// following differences: -// -// - The memory represented by a Block may require the use of safecopy to -// access. -// -// - Block does not carry a capacity and cannot be expanded. -// -// Blocks are immutable and may be copied by value. The zero value of Block -// represents an empty range, analogous to a nil []byte. -type Block struct { - // [start, start+length) is the represented memory. - // - // start is an unsafe.Pointer to ensure that Block prevents the represented - // memory from being garbage-collected. - start unsafe.Pointer - length int - - // needSafecopy is true if accessing the represented memory requires the - // use of safecopy. - needSafecopy bool -} - -// BlockFromSafeSlice returns a Block equivalent to slice, which is safe to -// access without safecopy. -func BlockFromSafeSlice(slice []byte) Block { - return blockFromSlice(slice, false) -} - -// BlockFromUnsafeSlice returns a Block equivalent to bs, which is not safe to -// access without safecopy. -func BlockFromUnsafeSlice(slice []byte) Block { - return blockFromSlice(slice, true) -} - -func blockFromSlice(slice []byte, needSafecopy bool) Block { - if len(slice) == 0 { - return Block{} - } - return Block{ - start: unsafe.Pointer(&slice[0]), - length: len(slice), - needSafecopy: needSafecopy, - } -} - -// BlockFromSafePointer returns a Block equivalent to [ptr, ptr+len), which is -// safe to access without safecopy. -// -// Preconditions: ptr+len does not overflow. -func BlockFromSafePointer(ptr unsafe.Pointer, len int) Block { - return blockFromPointer(ptr, len, false) -} - -// BlockFromUnsafePointer returns a Block equivalent to [ptr, ptr+len), which -// is not safe to access without safecopy. -// -// Preconditions: ptr+len does not overflow. -func BlockFromUnsafePointer(ptr unsafe.Pointer, len int) Block { - return blockFromPointer(ptr, len, true) -} - -func blockFromPointer(ptr unsafe.Pointer, len int, needSafecopy bool) Block { - if uptr := uintptr(ptr); uptr+uintptr(len) < uptr { - panic(fmt.Sprintf("ptr %#x + len %#x overflows", ptr, len)) - } - return Block{ - start: ptr, - length: len, - needSafecopy: needSafecopy, - } -} - -// DropFirst returns a Block equivalent to b, but with the first n bytes -// omitted. It is analogous to the [n:] operation on a slice, except that if n -// > b.Len(), DropFirst returns an empty Block instead of panicking. -// -// Preconditions: n >= 0. -func (b Block) DropFirst(n int) Block { - if n < 0 { - panic(fmt.Sprintf("invalid n: %d", n)) - } - return b.DropFirst64(uint64(n)) -} - -// DropFirst64 is equivalent to DropFirst but takes a uint64. -func (b Block) DropFirst64(n uint64) Block { - if n >= uint64(b.length) { - return Block{} - } - return Block{ - start: unsafe.Pointer(uintptr(b.start) + uintptr(n)), - length: b.length - int(n), - needSafecopy: b.needSafecopy, - } -} - -// TakeFirst returns a Block equivalent to the first n bytes of b. It is -// analogous to the [:n] operation on a slice, except that if n > b.Len(), -// TakeFirst returns a copy of b instead of panicking. -// -// Preconditions: n >= 0. -func (b Block) TakeFirst(n int) Block { - if n < 0 { - panic(fmt.Sprintf("invalid n: %d", n)) - } - return b.TakeFirst64(uint64(n)) -} - -// TakeFirst64 is equivalent to TakeFirst but takes a uint64. -func (b Block) TakeFirst64(n uint64) Block { - if n == 0 { - return Block{} - } - if n >= uint64(b.length) { - return b - } - return Block{ - start: b.start, - length: int(n), - needSafecopy: b.needSafecopy, - } -} - -// ToSlice returns a []byte equivalent to b. -func (b Block) ToSlice() []byte { - var bs []byte - hdr := (*reflect.SliceHeader)(unsafe.Pointer(&bs)) - hdr.Data = uintptr(b.start) - hdr.Len = b.length - hdr.Cap = b.length - return bs -} - -// Addr returns b's start address as a uintptr. It returns uintptr instead of -// unsafe.Pointer so that code using safemem cannot obtain unsafe.Pointers -// without importing the unsafe package explicitly. -// -// Note that a uintptr is not recognized as a pointer by the garbage collector, -// such that if there are no uses of b after a call to b.Addr() and the address -// is to Go-managed memory, the returned uintptr does not prevent garbage -// collection of the pointee. -func (b Block) Addr() uintptr { - return uintptr(b.start) -} - -// Len returns b's length in bytes. -func (b Block) Len() int { - return b.length -} - -// NeedSafecopy returns true if accessing b.ToSlice() requires the use of safecopy. -func (b Block) NeedSafecopy() bool { - return b.needSafecopy -} - -// String implements fmt.Stringer.String. -func (b Block) String() string { - if uintptr(b.start) == 0 && b.length == 0 { - return "" - } - var suffix string - if b.needSafecopy { - suffix = "*" - } - return fmt.Sprintf("[%#x-%#x)%s", uintptr(b.start), uintptr(b.start)+uintptr(b.length), suffix) -} - -// Copy copies src.Len() or dst.Len() bytes, whichever is less, from src -// to dst and returns the number of bytes copied. -// -// If src and dst overlap, the data stored in dst is unspecified. -func Copy(dst, src Block) (int, error) { - if !dst.needSafecopy && !src.needSafecopy { - return copy(dst.ToSlice(), src.ToSlice()), nil - } - - n := dst.length - if n > src.length { - n = src.length - } - if n == 0 { - return 0, nil - } - - switch { - case dst.needSafecopy && !src.needSafecopy: - return safecopy.CopyOut(dst.start, src.TakeFirst(n).ToSlice()) - case !dst.needSafecopy && src.needSafecopy: - return safecopy.CopyIn(dst.TakeFirst(n).ToSlice(), src.start) - case dst.needSafecopy && src.needSafecopy: - n64, err := safecopy.Copy(dst.start, src.start, uintptr(n)) - return int(n64), err - default: - panic("unreachable") - } -} - -// Zero sets all bytes in dst to 0 and returns the number of bytes zeroed. -func Zero(dst Block) (int, error) { - if !dst.needSafecopy { - bs := dst.ToSlice() - for i := range bs { - bs[i] = 0 - } - return len(bs), nil - } - - n64, err := safecopy.ZeroOut(dst.start, uintptr(dst.length)) - return int(n64), err -} - -// Safecopy atomics are no slower than non-safecopy atomics, so use the former -// even when !b.needSafecopy to get consistent alignment checking. - -// SwapUint32 invokes safecopy.SwapUint32 on the first 4 bytes of b. -// -// Preconditions: b.Len() >= 4. -func SwapUint32(b Block, new uint32) (uint32, error) { - if b.length < 4 { - panic(fmt.Sprintf("insufficient length: %d", b.length)) - } - return safecopy.SwapUint32(b.start, new) -} - -// SwapUint64 invokes safecopy.SwapUint64 on the first 8 bytes of b. -// -// Preconditions: b.Len() >= 8. -func SwapUint64(b Block, new uint64) (uint64, error) { - if b.length < 8 { - panic(fmt.Sprintf("insufficient length: %d", b.length)) - } - return safecopy.SwapUint64(b.start, new) -} - -// CompareAndSwapUint32 invokes safecopy.CompareAndSwapUint32 on the first 4 -// bytes of b. -// -// Preconditions: b.Len() >= 4. -func CompareAndSwapUint32(b Block, old, new uint32) (uint32, error) { - if b.length < 4 { - panic(fmt.Sprintf("insufficient length: %d", b.length)) - } - return safecopy.CompareAndSwapUint32(b.start, old, new) -} - -// LoadUint32 invokes safecopy.LoadUint32 on the first 4 bytes of b. -// -// Preconditions: b.Len() >= 4. -func LoadUint32(b Block) (uint32, error) { - if b.length < 4 { - panic(fmt.Sprintf("insufficient length: %d", b.length)) - } - return safecopy.LoadUint32(b.start) -} diff --git a/pkg/sentry/safemem/io.go b/pkg/sentry/safemem/io.go deleted file mode 100644 index f039a5c34..000000000 --- a/pkg/sentry/safemem/io.go +++ /dev/null @@ -1,392 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -package safemem - -import ( - "errors" - "io" - "math" -) - -// ErrEndOfBlockSeq is returned by BlockSeqWriter when attempting to write -// beyond the end of the BlockSeq. -var ErrEndOfBlockSeq = errors.New("write beyond end of BlockSeq") - -// Reader represents a streaming byte source like io.Reader. -type Reader interface { - // ReadToBlocks reads up to dsts.NumBytes() bytes into dsts and returns the - // number of bytes read. It may return a partial read without an error - // (i.e. (n, nil) where 0 < n < dsts.NumBytes()). It should not return a - // full read with an error (i.e. (dsts.NumBytes(), err) where err != nil); - // note that this differs from io.Reader.Read (in particular, io.EOF should - // not be returned if ReadToBlocks successfully reads dsts.NumBytes() - // bytes.) - ReadToBlocks(dsts BlockSeq) (uint64, error) -} - -// Writer represents a streaming byte sink like io.Writer. -type Writer interface { - // WriteFromBlocks writes up to srcs.NumBytes() bytes from srcs and returns - // the number of bytes written. It may return a partial write without an - // error (i.e. (n, nil) where 0 < n < srcs.NumBytes()). It should not - // return a full write with an error (i.e. srcs.NumBytes(), err) where err - // != nil). - WriteFromBlocks(srcs BlockSeq) (uint64, error) -} - -// ReadFullToBlocks repeatedly invokes r.ReadToBlocks until dsts.NumBytes() -// bytes have been read or ReadToBlocks returns an error. -func ReadFullToBlocks(r Reader, dsts BlockSeq) (uint64, error) { - var done uint64 - for !dsts.IsEmpty() { - n, err := r.ReadToBlocks(dsts) - done += n - if err != nil { - return done, err - } - dsts = dsts.DropFirst64(n) - } - return done, nil -} - -// WriteFullFromBlocks repeatedly invokes w.WriteFromBlocks until -// srcs.NumBytes() bytes have been written or WriteFromBlocks returns an error. -func WriteFullFromBlocks(w Writer, srcs BlockSeq) (uint64, error) { - var done uint64 - for !srcs.IsEmpty() { - n, err := w.WriteFromBlocks(srcs) - done += n - if err != nil { - return done, err - } - srcs = srcs.DropFirst64(n) - } - return done, nil -} - -// BlockSeqReader implements Reader by reading from a BlockSeq. -type BlockSeqReader struct { - Blocks BlockSeq -} - -// ReadToBlocks implements Reader.ReadToBlocks. -func (r *BlockSeqReader) ReadToBlocks(dsts BlockSeq) (uint64, error) { - n, err := CopySeq(dsts, r.Blocks) - r.Blocks = r.Blocks.DropFirst64(n) - if err != nil { - return n, err - } - if n < dsts.NumBytes() { - return n, io.EOF - } - return n, nil -} - -// BlockSeqWriter implements Writer by writing to a BlockSeq. -type BlockSeqWriter struct { - Blocks BlockSeq -} - -// WriteFromBlocks implements Writer.WriteFromBlocks. -func (w *BlockSeqWriter) WriteFromBlocks(srcs BlockSeq) (uint64, error) { - n, err := CopySeq(w.Blocks, srcs) - w.Blocks = w.Blocks.DropFirst64(n) - if err != nil { - return n, err - } - if n < srcs.NumBytes() { - return n, ErrEndOfBlockSeq - } - return n, nil -} - -// ReaderFunc implements Reader for a function with the semantics of -// Reader.ReadToBlocks. -type ReaderFunc func(dsts BlockSeq) (uint64, error) - -// ReadToBlocks implements Reader.ReadToBlocks. -func (f ReaderFunc) ReadToBlocks(dsts BlockSeq) (uint64, error) { - return f(dsts) -} - -// WriterFunc implements Writer for a function with the semantics of -// Writer.WriteFromBlocks. -type WriterFunc func(srcs BlockSeq) (uint64, error) - -// WriteFromBlocks implements Writer.WriteFromBlocks. -func (f WriterFunc) WriteFromBlocks(srcs BlockSeq) (uint64, error) { - return f(srcs) -} - -// ToIOReader implements io.Reader for a (safemem.)Reader. -// -// ToIOReader will return a successful partial read iff Reader.ReadToBlocks does -// so. -type ToIOReader struct { - Reader Reader -} - -// Read implements io.Reader.Read. -func (r ToIOReader) Read(dst []byte) (int, error) { - n, err := r.Reader.ReadToBlocks(BlockSeqOf(BlockFromSafeSlice(dst))) - return int(n), err -} - -// ToIOWriter implements io.Writer for a (safemem.)Writer. -type ToIOWriter struct { - Writer Writer -} - -// Write implements io.Writer.Write. -func (w ToIOWriter) Write(src []byte) (int, error) { - // io.Writer does not permit partial writes. - n, err := WriteFullFromBlocks(w.Writer, BlockSeqOf(BlockFromSafeSlice(src))) - return int(n), err -} - -// FromIOReader implements Reader for an io.Reader by repeatedly invoking -// io.Reader.Read until it returns an error or partial read. This is not -// thread-safe. -// -// FromIOReader will return a successful partial read iff Reader.Read does so. -type FromIOReader struct { - Reader io.Reader -} - -// ReadToBlocks implements Reader.ReadToBlocks. -func (r FromIOReader) ReadToBlocks(dsts BlockSeq) (uint64, error) { - var buf []byte - var done uint64 - for !dsts.IsEmpty() { - dst := dsts.Head() - var n int - var err error - n, buf, err = r.readToBlock(dst, buf) - done += uint64(n) - if n != dst.Len() { - return done, err - } - dsts = dsts.Tail() - if err != nil { - if dsts.IsEmpty() && err == io.EOF { - return done, nil - } - return done, err - } - } - return done, nil -} - -func (r FromIOReader) readToBlock(dst Block, buf []byte) (int, []byte, error) { - // io.Reader isn't safecopy-aware, so we have to buffer Blocks that require - // safecopy. - if !dst.NeedSafecopy() { - n, err := r.Reader.Read(dst.ToSlice()) - return n, buf, err - } - if len(buf) < dst.Len() { - buf = make([]byte, dst.Len()) - } - rn, rerr := r.Reader.Read(buf[:dst.Len()]) - wbn, wberr := Copy(dst, BlockFromSafeSlice(buf[:rn])) - if wberr != nil { - return wbn, buf, wberr - } - return wbn, buf, rerr -} - -// FromIOReaderAt implements Reader for an io.ReaderAt. Does not repeatedly -// invoke io.ReaderAt.ReadAt because ReadAt is more strict than Read. A partial -// read indicates an error. This is not thread-safe. -type FromIOReaderAt struct { - ReaderAt io.ReaderAt - Offset int64 -} - -// ReadToBlocks implements Reader.ReadToBlocks. -func (r FromIOReaderAt) ReadToBlocks(dsts BlockSeq) (uint64, error) { - var buf []byte - var done uint64 - for !dsts.IsEmpty() { - dst := dsts.Head() - var n int - var err error - n, buf, err = r.readToBlock(dst, buf) - done += uint64(n) - if n != dst.Len() { - return done, err - } - dsts = dsts.Tail() - if err != nil { - if dsts.IsEmpty() && err == io.EOF { - return done, nil - } - return done, err - } - } - return done, nil -} - -func (r FromIOReaderAt) readToBlock(dst Block, buf []byte) (int, []byte, error) { - // io.Reader isn't safecopy-aware, so we have to buffer Blocks that require - // safecopy. - if !dst.NeedSafecopy() { - n, err := r.ReaderAt.ReadAt(dst.ToSlice(), r.Offset) - r.Offset += int64(n) - return n, buf, err - } - if len(buf) < dst.Len() { - buf = make([]byte, dst.Len()) - } - rn, rerr := r.ReaderAt.ReadAt(buf[:dst.Len()], r.Offset) - r.Offset += int64(rn) - wbn, wberr := Copy(dst, BlockFromSafeSlice(buf[:rn])) - if wberr != nil { - return wbn, buf, wberr - } - return wbn, buf, rerr -} - -// FromIOWriter implements Writer for an io.Writer by repeatedly invoking -// io.Writer.Write until it returns an error or partial write. -// -// FromIOWriter will tolerate implementations of io.Writer.Write that return -// partial writes with a nil error in contravention of io.Writer's -// requirements, since Writer is permitted to do so. FromIOWriter will return a -// successful partial write iff Writer.Write does so. -type FromIOWriter struct { - Writer io.Writer -} - -// WriteFromBlocks implements Writer.WriteFromBlocks. -func (w FromIOWriter) WriteFromBlocks(srcs BlockSeq) (uint64, error) { - var buf []byte - var done uint64 - for !srcs.IsEmpty() { - src := srcs.Head() - var n int - var err error - n, buf, err = w.writeFromBlock(src, buf) - done += uint64(n) - if n != src.Len() || err != nil { - return done, err - } - srcs = srcs.Tail() - } - return done, nil -} - -func (w FromIOWriter) writeFromBlock(src Block, buf []byte) (int, []byte, error) { - // io.Writer isn't safecopy-aware, so we have to buffer Blocks that require - // safecopy. - if !src.NeedSafecopy() { - n, err := w.Writer.Write(src.ToSlice()) - return n, buf, err - } - if len(buf) < src.Len() { - buf = make([]byte, src.Len()) - } - bufn, buferr := Copy(BlockFromSafeSlice(buf[:src.Len()]), src) - wn, werr := w.Writer.Write(buf[:bufn]) - if werr != nil { - return wn, buf, werr - } - return wn, buf, buferr -} - -// FromVecReaderFunc implements Reader for a function that reads data into a -// [][]byte and returns the number of bytes read as an int64. -type FromVecReaderFunc struct { - ReadVec func(dsts [][]byte) (int64, error) -} - -// ReadToBlocks implements Reader.ReadToBlocks. -// -// ReadToBlocks calls r.ReadVec at most once. -func (r FromVecReaderFunc) ReadToBlocks(dsts BlockSeq) (uint64, error) { - if dsts.IsEmpty() { - return 0, nil - } - // Ensure that we don't pass a [][]byte with a total length > MaxInt64. - dsts = dsts.TakeFirst64(uint64(math.MaxInt64)) - dstSlices := make([][]byte, 0, dsts.NumBlocks()) - // Buffer Blocks that require safecopy. - for tmp := dsts; !tmp.IsEmpty(); tmp = tmp.Tail() { - dst := tmp.Head() - if dst.NeedSafecopy() { - dstSlices = append(dstSlices, make([]byte, dst.Len())) - } else { - dstSlices = append(dstSlices, dst.ToSlice()) - } - } - rn, rerr := r.ReadVec(dstSlices) - dsts = dsts.TakeFirst64(uint64(rn)) - var done uint64 - var i int - for !dsts.IsEmpty() { - dst := dsts.Head() - if dst.NeedSafecopy() { - n, err := Copy(dst, BlockFromSafeSlice(dstSlices[i])) - done += uint64(n) - if err != nil { - return done, err - } - } else { - done += uint64(dst.Len()) - } - dsts = dsts.Tail() - i++ - } - return done, rerr -} - -// FromVecWriterFunc implements Writer for a function that writes data from a -// [][]byte and returns the number of bytes written. -type FromVecWriterFunc struct { - WriteVec func(srcs [][]byte) (int64, error) -} - -// WriteFromBlocks implements Writer.WriteFromBlocks. -// -// WriteFromBlocks calls w.WriteVec at most once. -func (w FromVecWriterFunc) WriteFromBlocks(srcs BlockSeq) (uint64, error) { - if srcs.IsEmpty() { - return 0, nil - } - // Ensure that we don't pass a [][]byte with a total length > MaxInt64. - srcs = srcs.TakeFirst64(uint64(math.MaxInt64)) - srcSlices := make([][]byte, 0, srcs.NumBlocks()) - // Buffer Blocks that require safecopy. - var buferr error - for tmp := srcs; !tmp.IsEmpty(); tmp = tmp.Tail() { - src := tmp.Head() - if src.NeedSafecopy() { - slice := make([]byte, src.Len()) - n, err := Copy(BlockFromSafeSlice(slice), src) - srcSlices = append(srcSlices, slice[:n]) - if err != nil { - buferr = err - break - } - } else { - srcSlices = append(srcSlices, src.ToSlice()) - } - } - n, err := w.WriteVec(srcSlices) - if err != nil { - return uint64(n), err - } - return uint64(n), buferr -} diff --git a/pkg/sentry/safemem/io_test.go b/pkg/sentry/safemem/io_test.go deleted file mode 100644 index 629741bee..000000000 --- a/pkg/sentry/safemem/io_test.go +++ /dev/null @@ -1,199 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -package safemem - -import ( - "bytes" - "io" - "testing" -) - -func makeBlocks(slices ...[]byte) []Block { - blocks := make([]Block, 0, len(slices)) - for _, s := range slices { - blocks = append(blocks, BlockFromSafeSlice(s)) - } - return blocks -} - -func TestFromIOReaderFullRead(t *testing.T) { - r := FromIOReader{bytes.NewBufferString("foobar")} - dsts := makeBlocks(make([]byte, 3), make([]byte, 3)) - n, err := r.ReadToBlocks(BlockSeqFromSlice(dsts)) - if wantN := uint64(6); n != wantN || err != nil { - t.Errorf("ReadToBlocks: got (%v, %v), wanted (%v, nil)", n, err, wantN) - } - for i, want := range [][]byte{[]byte("foo"), []byte("bar")} { - if got := dsts[i].ToSlice(); !bytes.Equal(got, want) { - t.Errorf("dsts[%d]: got %q, wanted %q", i, got, want) - } - } -} - -type eofHidingReader struct { - Reader io.Reader -} - -func (r eofHidingReader) Read(dst []byte) (int, error) { - n, err := r.Reader.Read(dst) - if err == io.EOF { - return n, nil - } - return n, err -} - -func TestFromIOReaderPartialRead(t *testing.T) { - r := FromIOReader{eofHidingReader{bytes.NewBufferString("foob")}} - dsts := makeBlocks(make([]byte, 3), make([]byte, 3)) - n, err := r.ReadToBlocks(BlockSeqFromSlice(dsts)) - // FromIOReader should stop after the eofHidingReader returns (1, nil) - // for a 3-byte read. - if wantN := uint64(4); n != wantN || err != nil { - t.Errorf("ReadToBlocks: got (%v, %v), wanted (%v, nil)", n, err, wantN) - } - for i, want := range [][]byte{[]byte("foo"), []byte("b\x00\x00")} { - if got := dsts[i].ToSlice(); !bytes.Equal(got, want) { - t.Errorf("dsts[%d]: got %q, wanted %q", i, got, want) - } - } -} - -type singleByteReader struct { - Reader io.Reader -} - -func (r singleByteReader) Read(dst []byte) (int, error) { - if len(dst) == 0 { - return r.Reader.Read(dst) - } - return r.Reader.Read(dst[:1]) -} - -func TestSingleByteReader(t *testing.T) { - r := FromIOReader{singleByteReader{bytes.NewBufferString("foobar")}} - dsts := makeBlocks(make([]byte, 3), make([]byte, 3)) - n, err := r.ReadToBlocks(BlockSeqFromSlice(dsts)) - // FromIOReader should stop after the singleByteReader returns (1, nil) - // for a 3-byte read. - if wantN := uint64(1); n != wantN || err != nil { - t.Errorf("ReadToBlocks: got (%v, %v), wanted (%v, nil)", n, err, wantN) - } - for i, want := range [][]byte{[]byte("f\x00\x00"), []byte("\x00\x00\x00")} { - if got := dsts[i].ToSlice(); !bytes.Equal(got, want) { - t.Errorf("dsts[%d]: got %q, wanted %q", i, got, want) - } - } -} - -func TestReadFullToBlocks(t *testing.T) { - r := FromIOReader{singleByteReader{bytes.NewBufferString("foobar")}} - dsts := makeBlocks(make([]byte, 3), make([]byte, 3)) - n, err := ReadFullToBlocks(r, BlockSeqFromSlice(dsts)) - // ReadFullToBlocks should call into FromIOReader => singleByteReader - // repeatedly until dsts is exhausted. - if wantN := uint64(6); n != wantN || err != nil { - t.Errorf("ReadFullToBlocks: got (%v, %v), wanted (%v, nil)", n, err, wantN) - } - for i, want := range [][]byte{[]byte("foo"), []byte("bar")} { - if got := dsts[i].ToSlice(); !bytes.Equal(got, want) { - t.Errorf("dsts[%d]: got %q, wanted %q", i, got, want) - } - } -} - -func TestFromIOWriterFullWrite(t *testing.T) { - srcs := makeBlocks([]byte("foo"), []byte("bar")) - var dst bytes.Buffer - w := FromIOWriter{&dst} - n, err := w.WriteFromBlocks(BlockSeqFromSlice(srcs)) - if wantN := uint64(6); n != wantN || err != nil { - t.Errorf("WriteFromBlocks: got (%v, %v), wanted (%v, nil)", n, err, wantN) - } - if got, want := dst.Bytes(), []byte("foobar"); !bytes.Equal(got, want) { - t.Errorf("dst: got %q, wanted %q", got, want) - } -} - -type limitedWriter struct { - Writer io.Writer - Done int - Limit int -} - -func (w *limitedWriter) Write(src []byte) (int, error) { - count := len(src) - if count > (w.Limit - w.Done) { - count = w.Limit - w.Done - } - n, err := w.Writer.Write(src[:count]) - w.Done += n - return n, err -} - -func TestFromIOWriterPartialWrite(t *testing.T) { - srcs := makeBlocks([]byte("foo"), []byte("bar")) - var dst bytes.Buffer - w := FromIOWriter{&limitedWriter{&dst, 0, 4}} - n, err := w.WriteFromBlocks(BlockSeqFromSlice(srcs)) - // FromIOWriter should stop after the limitedWriter returns (1, nil) for a - // 3-byte write. - if wantN := uint64(4); n != wantN || err != nil { - t.Errorf("WriteFromBlocks: got (%v, %v), wanted (%v, nil)", n, err, wantN) - } - if got, want := dst.Bytes(), []byte("foob"); !bytes.Equal(got, want) { - t.Errorf("dst: got %q, wanted %q", got, want) - } -} - -type singleByteWriter struct { - Writer io.Writer -} - -func (w singleByteWriter) Write(src []byte) (int, error) { - if len(src) == 0 { - return w.Writer.Write(src) - } - return w.Writer.Write(src[:1]) -} - -func TestSingleByteWriter(t *testing.T) { - srcs := makeBlocks([]byte("foo"), []byte("bar")) - var dst bytes.Buffer - w := FromIOWriter{singleByteWriter{&dst}} - n, err := w.WriteFromBlocks(BlockSeqFromSlice(srcs)) - // FromIOWriter should stop after the singleByteWriter returns (1, nil) - // for a 3-byte write. - if wantN := uint64(1); n != wantN || err != nil { - t.Errorf("WriteFromBlocks: got (%v, %v), wanted (%v, nil)", n, err, wantN) - } - if got, want := dst.Bytes(), []byte("f"); !bytes.Equal(got, want) { - t.Errorf("dst: got %q, wanted %q", got, want) - } -} - -func TestWriteFullToBlocks(t *testing.T) { - srcs := makeBlocks([]byte("foo"), []byte("bar")) - var dst bytes.Buffer - w := FromIOWriter{singleByteWriter{&dst}} - n, err := WriteFullFromBlocks(w, BlockSeqFromSlice(srcs)) - // WriteFullToBlocks should call into FromIOWriter => singleByteWriter - // repeatedly until srcs is exhausted. - if wantN := uint64(6); n != wantN || err != nil { - t.Errorf("WriteFullFromBlocks: got (%v, %v), wanted (%v, nil)", n, err, wantN) - } - if got, want := dst.Bytes(), []byte("foobar"); !bytes.Equal(got, want) { - t.Errorf("dst: got %q, wanted %q", got, want) - } -} diff --git a/pkg/sentry/safemem/safemem.go b/pkg/sentry/safemem/safemem.go deleted file mode 100644 index 3e70d33a2..000000000 --- a/pkg/sentry/safemem/safemem.go +++ /dev/null @@ -1,16 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -// Package safemem provides the Block and BlockSeq types. -package safemem diff --git a/pkg/sentry/safemem/seq_test.go b/pkg/sentry/safemem/seq_test.go deleted file mode 100644 index eba4bb535..000000000 --- a/pkg/sentry/safemem/seq_test.go +++ /dev/null @@ -1,196 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -package safemem - -import ( - "bytes" - "reflect" - "testing" -) - -type blockSeqTest struct { - desc string - - pieces []string - haveOffset bool - offset uint64 - haveLimit bool - limit uint64 - - want string -} - -func (t blockSeqTest) NonEmptyByteSlices() [][]byte { - // t is a value, so we can mutate it freely. - slices := make([][]byte, 0, len(t.pieces)) - for _, str := range t.pieces { - if t.haveOffset { - strOff := t.offset - if strOff > uint64(len(str)) { - strOff = uint64(len(str)) - } - str = str[strOff:] - t.offset -= strOff - } - if t.haveLimit { - strLim := t.limit - if strLim > uint64(len(str)) { - strLim = uint64(len(str)) - } - str = str[:strLim] - t.limit -= strLim - } - if len(str) != 0 { - slices = append(slices, []byte(str)) - } - } - return slices -} - -func (t blockSeqTest) BlockSeq() BlockSeq { - blocks := make([]Block, 0, len(t.pieces)) - for _, str := range t.pieces { - blocks = append(blocks, BlockFromSafeSlice([]byte(str))) - } - bs := BlockSeqFromSlice(blocks) - if t.haveOffset { - bs = bs.DropFirst64(t.offset) - } - if t.haveLimit { - bs = bs.TakeFirst64(t.limit) - } - return bs -} - -var blockSeqTests = []blockSeqTest{ - { - desc: "Empty sequence", - }, - { - desc: "Sequence of length 1", - pieces: []string{"foobar"}, - want: "foobar", - }, - { - desc: "Sequence of length 2", - pieces: []string{"foo", "bar"}, - want: "foobar", - }, - { - desc: "Empty Blocks", - pieces: []string{"", "foo", "", "", "bar", ""}, - want: "foobar", - }, - { - desc: "Sequence with non-zero offset", - pieces: []string{"foo", "bar"}, - haveOffset: true, - offset: 2, - want: "obar", - }, - { - desc: "Sequence with non-maximal limit", - pieces: []string{"foo", "bar"}, - haveLimit: true, - limit: 5, - want: "fooba", - }, - { - desc: "Sequence with offset and limit", - pieces: []string{"foo", "bar"}, - haveOffset: true, - offset: 2, - haveLimit: true, - limit: 3, - want: "oba", - }, -} - -func TestBlockSeqNumBytes(t *testing.T) { - for _, test := range blockSeqTests { - t.Run(test.desc, func(t *testing.T) { - if got, want := test.BlockSeq().NumBytes(), uint64(len(test.want)); got != want { - t.Errorf("NumBytes: got %d, wanted %d", got, want) - } - }) - } -} - -func TestBlockSeqIterBlocks(t *testing.T) { - // Tests BlockSeq iteration using Head/Tail. - for _, test := range blockSeqTests { - t.Run(test.desc, func(t *testing.T) { - srcs := test.BlockSeq() - // "Note that a non-nil empty slice and a nil slice ... are not - // deeply equal." - reflect - slices := make([][]byte, 0, 0) - for !srcs.IsEmpty() { - src := srcs.Head() - slices = append(slices, src.ToSlice()) - nextSrcs := srcs.Tail() - if got, want := nextSrcs.NumBytes(), srcs.NumBytes()-uint64(src.Len()); got != want { - t.Fatalf("%v.Tail(): got %v (%d bytes), wanted %d bytes", srcs, nextSrcs, got, want) - } - srcs = nextSrcs - } - if wantSlices := test.NonEmptyByteSlices(); !reflect.DeepEqual(slices, wantSlices) { - t.Errorf("Accumulated slices: got %v, wanted %v", slices, wantSlices) - } - }) - } -} - -func TestBlockSeqIterBytes(t *testing.T) { - // Tests BlockSeq iteration using Head/DropFirst. - for _, test := range blockSeqTests { - t.Run(test.desc, func(t *testing.T) { - srcs := test.BlockSeq() - var dst bytes.Buffer - for !srcs.IsEmpty() { - src := srcs.Head() - var b [1]byte - n, err := Copy(BlockFromSafeSlice(b[:]), src) - if n != 1 || err != nil { - t.Fatalf("Copy: got (%v, %v), wanted (1, nil)", n, err) - } - dst.WriteByte(b[0]) - nextSrcs := srcs.DropFirst(1) - if got, want := nextSrcs.NumBytes(), srcs.NumBytes()-1; got != want { - t.Fatalf("%v.DropFirst(1): got %v (%d bytes), wanted %d bytes", srcs, nextSrcs, got, want) - } - srcs = nextSrcs - } - if got := string(dst.Bytes()); got != test.want { - t.Errorf("Copied string: got %q, wanted %q", got, test.want) - } - }) - } -} - -func TestBlockSeqDropBeyondLimit(t *testing.T) { - blocks := []Block{BlockFromSafeSlice([]byte("123")), BlockFromSafeSlice([]byte("4"))} - bs := BlockSeqFromSlice(blocks) - if got, want := bs.NumBytes(), uint64(4); got != want { - t.Errorf("%v.NumBytes(): got %d, wanted %d", bs, got, want) - } - bs = bs.TakeFirst(1) - if got, want := bs.NumBytes(), uint64(1); got != want { - t.Errorf("%v.NumBytes(): got %d, wanted %d", bs, got, want) - } - bs = bs.DropFirst(2) - if got, want := bs.NumBytes(), uint64(0); got != want { - t.Errorf("%v.NumBytes(): got %d, wanted %d", bs, got, want) - } -} diff --git a/pkg/sentry/safemem/seq_unsafe.go b/pkg/sentry/safemem/seq_unsafe.go deleted file mode 100644 index 354a95dde..000000000 --- a/pkg/sentry/safemem/seq_unsafe.go +++ /dev/null @@ -1,299 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -package safemem - -import ( - "bytes" - "fmt" - "reflect" - "unsafe" -) - -// A BlockSeq represents a sequence of Blocks, each of which has non-zero -// length. -// -// BlockSeqs are immutable and may be copied by value. The zero value of -// BlockSeq represents an empty sequence. -type BlockSeq struct { - // If length is 0, then the BlockSeq is empty. Invariants: data == 0; - // offset == 0; limit == 0. - // - // If length is -1, then the BlockSeq represents the single Block{data, - // limit, false}. Invariants: offset == 0; limit > 0; limit does not - // overflow the range of an int. - // - // If length is -2, then the BlockSeq represents the single Block{data, - // limit, true}. Invariants: offset == 0; limit > 0; limit does not - // overflow the range of an int. - // - // Otherwise, length >= 2, and the BlockSeq represents the `length` Blocks - // in the array of Blocks starting at address `data`, starting at `offset` - // bytes into the first Block and limited to the following `limit` bytes. - // Invariants: data != 0; offset < len(data[0]); limit > 0; offset+limit <= - // the combined length of all Blocks in the array; the first Block in the - // array has non-zero length. - // - // length is never 1; sequences consisting of a single Block are always - // stored inline (with length < 0). - data unsafe.Pointer - length int - offset int - limit uint64 -} - -// BlockSeqOf returns a BlockSeq representing the single Block b. -func BlockSeqOf(b Block) BlockSeq { - bs := BlockSeq{ - data: b.start, - length: -1, - limit: uint64(b.length), - } - if b.needSafecopy { - bs.length = -2 - } - return bs -} - -// BlockSeqFromSlice returns a BlockSeq representing all Blocks in slice. -// If slice contains Blocks with zero length, BlockSeq will skip them during -// iteration. -// -// Whether the returned BlockSeq shares memory with slice is unspecified; -// clients should avoid mutating slices passed to BlockSeqFromSlice. -// -// Preconditions: The combined length of all Blocks in slice <= math.MaxUint64. -func BlockSeqFromSlice(slice []Block) BlockSeq { - slice = skipEmpty(slice) - var limit uint64 - for _, b := range slice { - sum := limit + uint64(b.Len()) - if sum < limit { - panic("BlockSeq length overflows uint64") - } - limit = sum - } - return blockSeqFromSliceLimited(slice, limit) -} - -// Preconditions: The combined length of all Blocks in slice <= limit. If -// len(slice) != 0, the first Block in slice has non-zero length, and limit > -// 0. -func blockSeqFromSliceLimited(slice []Block, limit uint64) BlockSeq { - switch len(slice) { - case 0: - return BlockSeq{} - case 1: - return BlockSeqOf(slice[0].TakeFirst64(limit)) - default: - return BlockSeq{ - data: unsafe.Pointer(&slice[0]), - length: len(slice), - limit: limit, - } - } -} - -func skipEmpty(slice []Block) []Block { - for i, b := range slice { - if b.Len() != 0 { - return slice[i:] - } - } - return nil -} - -// IsEmpty returns true if bs contains no Blocks. -// -// Invariants: bs.IsEmpty() == (bs.NumBlocks() == 0) == (bs.NumBytes() == 0). -// (Of these, prefer to use bs.IsEmpty().) -func (bs BlockSeq) IsEmpty() bool { - return bs.length == 0 -} - -// NumBlocks returns the number of Blocks in bs. -func (bs BlockSeq) NumBlocks() int { - // In general, we have to count: if bs represents a windowed slice then the - // slice may contain Blocks with zero length, and bs.length may be larger - // than the actual number of Blocks due to bs.limit. - var n int - for !bs.IsEmpty() { - n++ - bs = bs.Tail() - } - return n -} - -// NumBytes returns the sum of Block.Len() for all Blocks in bs. -func (bs BlockSeq) NumBytes() uint64 { - return bs.limit -} - -// Head returns the first Block in bs. -// -// Preconditions: !bs.IsEmpty(). -func (bs BlockSeq) Head() Block { - if bs.length == 0 { - panic("empty BlockSeq") - } - if bs.length < 0 { - return bs.internalBlock() - } - return (*Block)(bs.data).DropFirst(bs.offset).TakeFirst64(bs.limit) -} - -// Preconditions: bs.length < 0. -func (bs BlockSeq) internalBlock() Block { - return Block{ - start: bs.data, - length: int(bs.limit), - needSafecopy: bs.length == -2, - } -} - -// Tail returns a BlockSeq consisting of all Blocks in bs after the first. -// -// Preconditions: !bs.IsEmpty(). -func (bs BlockSeq) Tail() BlockSeq { - if bs.length == 0 { - panic("empty BlockSeq") - } - if bs.length < 0 { - return BlockSeq{} - } - head := (*Block)(bs.data).DropFirst(bs.offset) - headLen := uint64(head.Len()) - if headLen >= bs.limit { - // The head Block exhausts the limit, so the tail is empty. - return BlockSeq{} - } - var extSlice []Block - extSliceHdr := (*reflect.SliceHeader)(unsafe.Pointer(&extSlice)) - extSliceHdr.Data = uintptr(bs.data) - extSliceHdr.Len = bs.length - extSliceHdr.Cap = bs.length - tailSlice := skipEmpty(extSlice[1:]) - tailLimit := bs.limit - headLen - return blockSeqFromSliceLimited(tailSlice, tailLimit) -} - -// DropFirst returns a BlockSeq equivalent to bs, but with the first n bytes -// omitted. If n > bs.NumBytes(), DropFirst returns an empty BlockSeq. -// -// Preconditions: n >= 0. -func (bs BlockSeq) DropFirst(n int) BlockSeq { - if n < 0 { - panic(fmt.Sprintf("invalid n: %d", n)) - } - return bs.DropFirst64(uint64(n)) -} - -// DropFirst64 is equivalent to DropFirst but takes an uint64. -func (bs BlockSeq) DropFirst64(n uint64) BlockSeq { - if n >= bs.limit { - return BlockSeq{} - } - for { - // Calling bs.Head() here is surprisingly expensive, so inline getting - // the head's length. - var headLen uint64 - if bs.length < 0 { - headLen = bs.limit - } else { - headLen = uint64((*Block)(bs.data).Len() - bs.offset) - } - if n < headLen { - // Dropping ends partway through the head Block. - if bs.length < 0 { - return BlockSeqOf(bs.internalBlock().DropFirst64(n)) - } - bs.offset += int(n) - bs.limit -= n - return bs - } - n -= headLen - bs = bs.Tail() - } -} - -// TakeFirst returns a BlockSeq equivalent to the first n bytes of bs. If n > -// bs.NumBytes(), TakeFirst returns a BlockSeq equivalent to bs. -// -// Preconditions: n >= 0. -func (bs BlockSeq) TakeFirst(n int) BlockSeq { - if n < 0 { - panic(fmt.Sprintf("invalid n: %d", n)) - } - return bs.TakeFirst64(uint64(n)) -} - -// TakeFirst64 is equivalent to TakeFirst but takes a uint64. -func (bs BlockSeq) TakeFirst64(n uint64) BlockSeq { - if n == 0 { - return BlockSeq{} - } - if bs.limit > n { - bs.limit = n - } - return bs -} - -// String implements fmt.Stringer.String. -func (bs BlockSeq) String() string { - var buf bytes.Buffer - buf.WriteByte('[') - var sep string - for !bs.IsEmpty() { - buf.WriteString(sep) - sep = " " - buf.WriteString(bs.Head().String()) - bs = bs.Tail() - } - buf.WriteByte(']') - return buf.String() -} - -// CopySeq copies srcs.NumBytes() or dsts.NumBytes() bytes, whichever is less, -// from srcs to dsts and returns the number of bytes copied. -// -// If srcs and dsts overlap, the data stored in dsts is unspecified. -func CopySeq(dsts, srcs BlockSeq) (uint64, error) { - var done uint64 - for !dsts.IsEmpty() && !srcs.IsEmpty() { - dst := dsts.Head() - src := srcs.Head() - n, err := Copy(dst, src) - done += uint64(n) - if err != nil { - return done, err - } - dsts = dsts.DropFirst(n) - srcs = srcs.DropFirst(n) - } - return done, nil -} - -// ZeroSeq sets all bytes in dsts to 0 and returns the number of bytes zeroed. -func ZeroSeq(dsts BlockSeq) (uint64, error) { - var done uint64 - for !dsts.IsEmpty() { - n, err := Zero(dsts.Head()) - done += uint64(n) - if err != nil { - return done, err - } - dsts = dsts.DropFirst(n) - } - return done, nil -} diff --git a/pkg/sentry/socket/BUILD b/pkg/sentry/socket/BUILD index 8e2b97afb..611fa22c3 100644 --- a/pkg/sentry/socket/BUILD +++ b/pkg/sentry/socket/BUILD @@ -9,15 +9,15 @@ go_library( deps = [ "//pkg/abi/linux", "//pkg/binary", - "//pkg/sentry/context", + "//pkg/context", "//pkg/sentry/device", "//pkg/sentry/fs", "//pkg/sentry/fs/fsutil", "//pkg/sentry/kernel", "//pkg/sentry/kernel/time", "//pkg/sentry/socket/unix/transport", - "//pkg/sentry/usermem", "//pkg/syserr", "//pkg/tcpip", + "//pkg/usermem", ], ) diff --git a/pkg/sentry/socket/control/BUILD b/pkg/sentry/socket/control/BUILD index 3850f6345..79e16d6e8 100644 --- a/pkg/sentry/socket/control/BUILD +++ b/pkg/sentry/socket/control/BUILD @@ -12,13 +12,13 @@ go_library( deps = [ "//pkg/abi/linux", "//pkg/binary", - "//pkg/sentry/context", + "//pkg/context", "//pkg/sentry/fs", "//pkg/sentry/kernel", "//pkg/sentry/kernel/auth", "//pkg/sentry/socket", "//pkg/sentry/socket/unix/transport", - "//pkg/sentry/usermem", "//pkg/syserror", + "//pkg/usermem", ], ) diff --git a/pkg/sentry/socket/control/control.go b/pkg/sentry/socket/control/control.go index 1684dfc24..00265f15b 100644 --- a/pkg/sentry/socket/control/control.go +++ b/pkg/sentry/socket/control/control.go @@ -19,14 +19,14 @@ package control import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/binary" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/socket" "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) const maxInt = int(^uint(0) >> 1) diff --git a/pkg/sentry/socket/hostinet/BUILD b/pkg/sentry/socket/hostinet/BUILD index 42bf7be6a..5a07d5d0e 100644 --- a/pkg/sentry/socket/hostinet/BUILD +++ b/pkg/sentry/socket/hostinet/BUILD @@ -16,23 +16,23 @@ go_library( deps = [ "//pkg/abi/linux", "//pkg/binary", + "//pkg/context", "//pkg/fdnotifier", "//pkg/log", + "//pkg/safemem", "//pkg/sentry/arch", - "//pkg/sentry/context", "//pkg/sentry/device", "//pkg/sentry/fs", "//pkg/sentry/fs/fsutil", "//pkg/sentry/inet", "//pkg/sentry/kernel", "//pkg/sentry/kernel/time", - "//pkg/sentry/safemem", "//pkg/sentry/socket", "//pkg/sentry/socket/control", - "//pkg/sentry/usermem", "//pkg/syserr", "//pkg/syserror", "//pkg/tcpip/stack", + "//pkg/usermem", "//pkg/waiter", "@org_golang_x_sys//unix:go_default_library", ], diff --git a/pkg/sentry/socket/hostinet/socket.go b/pkg/sentry/socket/hostinet/socket.go index c957b0f1d..bde4c7a1e 100644 --- a/pkg/sentry/socket/hostinet/socket.go +++ b/pkg/sentry/socket/hostinet/socket.go @@ -21,19 +21,19 @@ import ( "golang.org/x/sys/unix" "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/binary" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fdnotifier" "gvisor.dev/gvisor/pkg/log" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/kernel" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" - "gvisor.dev/gvisor/pkg/sentry/safemem" "gvisor.dev/gvisor/pkg/sentry/socket" "gvisor.dev/gvisor/pkg/sentry/socket/control" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserr" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/socket/hostinet/socket_unsafe.go b/pkg/sentry/socket/hostinet/socket_unsafe.go index e69ec38c2..cd67234d2 100644 --- a/pkg/sentry/socket/hostinet/socket_unsafe.go +++ b/pkg/sentry/socket/hostinet/socket_unsafe.go @@ -19,14 +19,14 @@ import ( "unsafe" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/socket" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserr" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) func firstBytePtr(bs []byte) unsafe.Pointer { diff --git a/pkg/sentry/socket/hostinet/stack.go b/pkg/sentry/socket/hostinet/stack.go index e67b46c9e..034eca676 100644 --- a/pkg/sentry/socket/hostinet/stack.go +++ b/pkg/sentry/socket/hostinet/stack.go @@ -25,13 +25,13 @@ import ( "syscall" "gvisor.dev/gvisor/pkg/binary" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/log" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/inet" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserr" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/tcpip/stack" + "gvisor.dev/gvisor/pkg/usermem" ) var defaultRecvBufSize = inet.TCPBufferSize{ diff --git a/pkg/sentry/socket/netfilter/BUILD b/pkg/sentry/socket/netfilter/BUILD index ed34a8308..fa2a2cb66 100644 --- a/pkg/sentry/socket/netfilter/BUILD +++ b/pkg/sentry/socket/netfilter/BUILD @@ -15,10 +15,10 @@ go_library( "//pkg/binary", "//pkg/log", "//pkg/sentry/kernel", - "//pkg/sentry/usermem", "//pkg/syserr", "//pkg/tcpip", "//pkg/tcpip/iptables", "//pkg/tcpip/stack", + "//pkg/usermem", ], ) diff --git a/pkg/sentry/socket/netfilter/netfilter.go b/pkg/sentry/socket/netfilter/netfilter.go index c65c36081..6ef740463 100644 --- a/pkg/sentry/socket/netfilter/netfilter.go +++ b/pkg/sentry/socket/netfilter/netfilter.go @@ -23,11 +23,11 @@ import ( "gvisor.dev/gvisor/pkg/binary" "gvisor.dev/gvisor/pkg/log" "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserr" "gvisor.dev/gvisor/pkg/tcpip" "gvisor.dev/gvisor/pkg/tcpip/iptables" "gvisor.dev/gvisor/pkg/tcpip/stack" + "gvisor.dev/gvisor/pkg/usermem" ) // errorTargetName is used to mark targets as error targets. Error targets diff --git a/pkg/sentry/socket/netlink/BUILD b/pkg/sentry/socket/netlink/BUILD index baaac13c6..f8b8e467d 100644 --- a/pkg/sentry/socket/netlink/BUILD +++ b/pkg/sentry/socket/netlink/BUILD @@ -13,8 +13,8 @@ go_library( deps = [ "//pkg/abi/linux", "//pkg/binary", + "//pkg/context", "//pkg/sentry/arch", - "//pkg/sentry/context", "//pkg/sentry/device", "//pkg/sentry/fs", "//pkg/sentry/fs/fsutil", @@ -25,11 +25,11 @@ go_library( "//pkg/sentry/socket/netlink/port", "//pkg/sentry/socket/unix", "//pkg/sentry/socket/unix/transport", - "//pkg/sentry/usermem", "//pkg/sync", "//pkg/syserr", "//pkg/syserror", "//pkg/tcpip", + "//pkg/usermem", "//pkg/waiter", ], ) diff --git a/pkg/sentry/socket/netlink/message.go b/pkg/sentry/socket/netlink/message.go index ce0a1afd0..b21e0ca4b 100644 --- a/pkg/sentry/socket/netlink/message.go +++ b/pkg/sentry/socket/netlink/message.go @@ -20,7 +20,7 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/binary" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // alignUp rounds a length up to an alignment. diff --git a/pkg/sentry/socket/netlink/provider.go b/pkg/sentry/socket/netlink/provider.go index be005df24..07f860a49 100644 --- a/pkg/sentry/socket/netlink/provider.go +++ b/pkg/sentry/socket/netlink/provider.go @@ -18,7 +18,7 @@ import ( "fmt" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/socket" diff --git a/pkg/sentry/socket/netlink/route/BUILD b/pkg/sentry/socket/netlink/route/BUILD index 2137c7aeb..0234aadde 100644 --- a/pkg/sentry/socket/netlink/route/BUILD +++ b/pkg/sentry/socket/netlink/route/BUILD @@ -8,7 +8,7 @@ go_library( visibility = ["//pkg/sentry:internal"], deps = [ "//pkg/abi/linux", - "//pkg/sentry/context", + "//pkg/context", "//pkg/sentry/inet", "//pkg/sentry/kernel", "//pkg/sentry/kernel/auth", diff --git a/pkg/sentry/socket/netlink/route/protocol.go b/pkg/sentry/socket/netlink/route/protocol.go index 6b4a0ecf4..80a15d6cb 100644 --- a/pkg/sentry/socket/netlink/route/protocol.go +++ b/pkg/sentry/socket/netlink/route/protocol.go @@ -19,7 +19,7 @@ import ( "bytes" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/inet" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" diff --git a/pkg/sentry/socket/netlink/socket.go b/pkg/sentry/socket/netlink/socket.go index cea56f4ed..c4b95debb 100644 --- a/pkg/sentry/socket/netlink/socket.go +++ b/pkg/sentry/socket/netlink/socket.go @@ -20,8 +20,8 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/binary" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/device" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" @@ -32,11 +32,11 @@ import ( "gvisor.dev/gvisor/pkg/sentry/socket/netlink/port" "gvisor.dev/gvisor/pkg/sentry/socket/unix" "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserr" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/tcpip" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/socket/netlink/uevent/BUILD b/pkg/sentry/socket/netlink/uevent/BUILD index 73fbdf1eb..b6434923c 100644 --- a/pkg/sentry/socket/netlink/uevent/BUILD +++ b/pkg/sentry/socket/netlink/uevent/BUILD @@ -8,7 +8,7 @@ go_library( visibility = ["//pkg/sentry:internal"], deps = [ "//pkg/abi/linux", - "//pkg/sentry/context", + "//pkg/context", "//pkg/sentry/kernel", "//pkg/sentry/socket/netlink", "//pkg/syserr", diff --git a/pkg/sentry/socket/netlink/uevent/protocol.go b/pkg/sentry/socket/netlink/uevent/protocol.go index b5d7808d7..1ee4296bc 100644 --- a/pkg/sentry/socket/netlink/uevent/protocol.go +++ b/pkg/sentry/socket/netlink/uevent/protocol.go @@ -20,7 +20,7 @@ package uevent import ( "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/socket/netlink" "gvisor.dev/gvisor/pkg/syserr" diff --git a/pkg/sentry/socket/netstack/BUILD b/pkg/sentry/socket/netstack/BUILD index e3d1f90cb..ab01cb4fa 100644 --- a/pkg/sentry/socket/netstack/BUILD +++ b/pkg/sentry/socket/netstack/BUILD @@ -17,10 +17,11 @@ go_library( deps = [ "//pkg/abi/linux", "//pkg/binary", + "//pkg/context", "//pkg/log", "//pkg/metric", + "//pkg/safemem", "//pkg/sentry/arch", - "//pkg/sentry/context", "//pkg/sentry/device", "//pkg/sentry/fs", "//pkg/sentry/fs/fsutil", @@ -28,11 +29,9 @@ go_library( "//pkg/sentry/kernel", "//pkg/sentry/kernel/auth", "//pkg/sentry/kernel/time", - "//pkg/sentry/safemem", "//pkg/sentry/socket", "//pkg/sentry/socket/netfilter", "//pkg/sentry/unimpl", - "//pkg/sentry/usermem", "//pkg/sync", "//pkg/syserr", "//pkg/syserror", @@ -45,6 +44,7 @@ go_library( "//pkg/tcpip/stack", "//pkg/tcpip/transport/tcp", "//pkg/tcpip/transport/udp", + "//pkg/usermem", "//pkg/waiter", ], ) diff --git a/pkg/sentry/socket/netstack/netstack.go b/pkg/sentry/socket/netstack/netstack.go index 318acbeff..8619cc506 100644 --- a/pkg/sentry/socket/netstack/netstack.go +++ b/pkg/sentry/socket/netstack/netstack.go @@ -34,20 +34,19 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/binary" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/log" "gvisor.dev/gvisor/pkg/metric" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/inet" "gvisor.dev/gvisor/pkg/sentry/kernel" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" - "gvisor.dev/gvisor/pkg/sentry/safemem" "gvisor.dev/gvisor/pkg/sentry/socket" "gvisor.dev/gvisor/pkg/sentry/socket/netfilter" "gvisor.dev/gvisor/pkg/sentry/unimpl" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserr" "gvisor.dev/gvisor/pkg/syserror" @@ -57,6 +56,7 @@ import ( "gvisor.dev/gvisor/pkg/tcpip/stack" "gvisor.dev/gvisor/pkg/tcpip/transport/tcp" "gvisor.dev/gvisor/pkg/tcpip/transport/udp" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/socket/netstack/provider.go b/pkg/sentry/socket/netstack/provider.go index 2d2c1ba2a..5afff2564 100644 --- a/pkg/sentry/socket/netstack/provider.go +++ b/pkg/sentry/socket/netstack/provider.go @@ -18,7 +18,7 @@ import ( "syscall" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" diff --git a/pkg/sentry/socket/socket.go b/pkg/sentry/socket/socket.go index 2389a9cdb..50d9744e6 100644 --- a/pkg/sentry/socket/socket.go +++ b/pkg/sentry/socket/socket.go @@ -24,16 +24,16 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/binary" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/device" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/kernel" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserr" "gvisor.dev/gvisor/pkg/tcpip" + "gvisor.dev/gvisor/pkg/usermem" ) // ControlMessages represents the union of unix control messages and tcpip diff --git a/pkg/sentry/socket/unix/BUILD b/pkg/sentry/socket/unix/BUILD index bade18686..08743deba 100644 --- a/pkg/sentry/socket/unix/BUILD +++ b/pkg/sentry/socket/unix/BUILD @@ -12,23 +12,23 @@ go_library( visibility = ["//pkg/sentry:internal"], deps = [ "//pkg/abi/linux", + "//pkg/context", "//pkg/refs", + "//pkg/safemem", "//pkg/sentry/arch", - "//pkg/sentry/context", "//pkg/sentry/device", "//pkg/sentry/fs", "//pkg/sentry/fs/fsutil", "//pkg/sentry/kernel", "//pkg/sentry/kernel/time", - "//pkg/sentry/safemem", "//pkg/sentry/socket", "//pkg/sentry/socket/control", "//pkg/sentry/socket/netstack", "//pkg/sentry/socket/unix/transport", - "//pkg/sentry/usermem", "//pkg/syserr", "//pkg/syserror", "//pkg/tcpip", + "//pkg/usermem", "//pkg/waiter", ], ) diff --git a/pkg/sentry/socket/unix/io.go b/pkg/sentry/socket/unix/io.go index 2447f24ef..129949990 100644 --- a/pkg/sentry/socket/unix/io.go +++ b/pkg/sentry/socket/unix/io.go @@ -15,8 +15,8 @@ package unix import ( - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/safemem" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" "gvisor.dev/gvisor/pkg/tcpip" ) diff --git a/pkg/sentry/socket/unix/transport/BUILD b/pkg/sentry/socket/unix/transport/BUILD index 4bdfc9208..74bcd6300 100644 --- a/pkg/sentry/socket/unix/transport/BUILD +++ b/pkg/sentry/socket/unix/transport/BUILD @@ -28,9 +28,9 @@ go_library( visibility = ["//:sandbox"], deps = [ "//pkg/abi/linux", + "//pkg/context", "//pkg/ilist", "//pkg/refs", - "//pkg/sentry/context", "//pkg/sync", "//pkg/syserr", "//pkg/tcpip", diff --git a/pkg/sentry/socket/unix/transport/connectioned.go b/pkg/sentry/socket/unix/transport/connectioned.go index 9e6fbc111..ce5b94ee7 100644 --- a/pkg/sentry/socket/unix/transport/connectioned.go +++ b/pkg/sentry/socket/unix/transport/connectioned.go @@ -16,7 +16,7 @@ package transport import ( "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserr" "gvisor.dev/gvisor/pkg/tcpip" diff --git a/pkg/sentry/socket/unix/transport/connectionless.go b/pkg/sentry/socket/unix/transport/connectionless.go index 0322dec0b..4b06d63ac 100644 --- a/pkg/sentry/socket/unix/transport/connectionless.go +++ b/pkg/sentry/socket/unix/transport/connectionless.go @@ -16,7 +16,7 @@ package transport import ( "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/syserr" "gvisor.dev/gvisor/pkg/tcpip" "gvisor.dev/gvisor/pkg/waiter" diff --git a/pkg/sentry/socket/unix/transport/unix.go b/pkg/sentry/socket/unix/transport/unix.go index fcc0da332..dcbafe0e5 100644 --- a/pkg/sentry/socket/unix/transport/unix.go +++ b/pkg/sentry/socket/unix/transport/unix.go @@ -19,7 +19,7 @@ import ( "sync/atomic" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserr" "gvisor.dev/gvisor/pkg/tcpip" diff --git a/pkg/sentry/socket/unix/unix.go b/pkg/sentry/socket/unix/unix.go index 7f49ba864..4d30aa714 100644 --- a/pkg/sentry/socket/unix/unix.go +++ b/pkg/sentry/socket/unix/unix.go @@ -22,9 +22,9 @@ import ( "syscall" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/refs" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/kernel" @@ -33,10 +33,10 @@ import ( "gvisor.dev/gvisor/pkg/sentry/socket/control" "gvisor.dev/gvisor/pkg/sentry/socket/netstack" "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserr" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/tcpip" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/strace/BUILD b/pkg/sentry/strace/BUILD index ff6fafa63..762a946fe 100644 --- a/pkg/sentry/strace/BUILD +++ b/pkg/sentry/strace/BUILD @@ -34,7 +34,7 @@ go_library( "//pkg/sentry/socket/netlink", "//pkg/sentry/socket/netstack", "//pkg/sentry/syscalls/linux", - "//pkg/sentry/usermem", + "//pkg/usermem", ], ) diff --git a/pkg/sentry/strace/poll.go b/pkg/sentry/strace/poll.go index 5187594a7..074e80f9b 100644 --- a/pkg/sentry/strace/poll.go +++ b/pkg/sentry/strace/poll.go @@ -22,7 +22,7 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/sentry/kernel" slinux "gvisor.dev/gvisor/pkg/sentry/syscalls/linux" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // PollEventSet is the set of poll(2) event flags. diff --git a/pkg/sentry/strace/select.go b/pkg/sentry/strace/select.go index c77d418e6..3a4c32aa0 100644 --- a/pkg/sentry/strace/select.go +++ b/pkg/sentry/strace/select.go @@ -19,7 +19,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/syscalls/linux" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) func fdsFromSet(t *kernel.Task, set []byte) []int { diff --git a/pkg/sentry/strace/signal.go b/pkg/sentry/strace/signal.go index 5656d53eb..c41f36e3f 100644 --- a/pkg/sentry/strace/signal.go +++ b/pkg/sentry/strace/signal.go @@ -21,7 +21,7 @@ import ( "gvisor.dev/gvisor/pkg/abi" "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // signalNames contains the names of all named signals. diff --git a/pkg/sentry/strace/socket.go b/pkg/sentry/strace/socket.go index b6d7177f4..d2079c85f 100644 --- a/pkg/sentry/strace/socket.go +++ b/pkg/sentry/strace/socket.go @@ -26,7 +26,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/socket/netlink" "gvisor.dev/gvisor/pkg/sentry/socket/netstack" slinux "gvisor.dev/gvisor/pkg/sentry/syscalls/linux" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // SocketFamily are the possible socket(2) families. diff --git a/pkg/sentry/strace/strace.go b/pkg/sentry/strace/strace.go index 629c1f308..3fc4a47fc 100644 --- a/pkg/sentry/strace/strace.go +++ b/pkg/sentry/strace/strace.go @@ -33,7 +33,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel" pb "gvisor.dev/gvisor/pkg/sentry/strace/strace_go_proto" slinux "gvisor.dev/gvisor/pkg/sentry/syscalls/linux" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // DefaultLogMaximumSize is the default LogMaximumSize. diff --git a/pkg/sentry/syscalls/linux/BUILD b/pkg/sentry/syscalls/linux/BUILD index 7d74e0f70..8d6c52850 100644 --- a/pkg/sentry/syscalls/linux/BUILD +++ b/pkg/sentry/syscalls/linux/BUILD @@ -63,11 +63,12 @@ go_library( "//pkg/abi/linux", "//pkg/binary", "//pkg/bpf", + "//pkg/context", "//pkg/log", "//pkg/metric", "//pkg/rand", + "//pkg/safemem", "//pkg/sentry/arch", - "//pkg/sentry/context", "//pkg/sentry/fs", "//pkg/sentry/fs/anon", "//pkg/sentry/fs/lock", @@ -87,16 +88,15 @@ go_library( "//pkg/sentry/loader", "//pkg/sentry/memmap", "//pkg/sentry/mm", - "//pkg/sentry/safemem", "//pkg/sentry/socket", "//pkg/sentry/socket/control", "//pkg/sentry/socket/unix/transport", "//pkg/sentry/syscalls", "//pkg/sentry/usage", - "//pkg/sentry/usermem", "//pkg/sync", "//pkg/syserr", "//pkg/syserror", + "//pkg/usermem", "//pkg/waiter", ], ) diff --git a/pkg/sentry/syscalls/linux/linux64_amd64.go b/pkg/sentry/syscalls/linux/linux64_amd64.go index c76771a54..7435b50bf 100644 --- a/pkg/sentry/syscalls/linux/linux64_amd64.go +++ b/pkg/sentry/syscalls/linux/linux64_amd64.go @@ -20,8 +20,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/syscalls" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // AMD64 is a table of Linux amd64 syscall API with the corresponding syscall diff --git a/pkg/sentry/syscalls/linux/linux64_arm64.go b/pkg/sentry/syscalls/linux/linux64_arm64.go index d3587fda6..03a39fe65 100644 --- a/pkg/sentry/syscalls/linux/linux64_arm64.go +++ b/pkg/sentry/syscalls/linux/linux64_arm64.go @@ -20,8 +20,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/syscalls" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // ARM64 is a table of Linux arm64 syscall API with the corresponding syscall diff --git a/pkg/sentry/syscalls/linux/sigset.go b/pkg/sentry/syscalls/linux/sigset.go index 333013d8c..2ddb2b146 100644 --- a/pkg/sentry/syscalls/linux/sigset.go +++ b/pkg/sentry/syscalls/linux/sigset.go @@ -17,8 +17,8 @@ package linux import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // copyInSigSet copies in a sigset_t, checks its size, and ensures that KILL and diff --git a/pkg/sentry/syscalls/linux/sys_aio.go b/pkg/sentry/syscalls/linux/sys_aio.go index f56411bfe..b401978db 100644 --- a/pkg/sentry/syscalls/linux/sys_aio.go +++ b/pkg/sentry/syscalls/linux/sys_aio.go @@ -23,8 +23,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel/eventfd" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/mm" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // I/O commands. diff --git a/pkg/sentry/syscalls/linux/sys_epoll.go b/pkg/sentry/syscalls/linux/sys_epoll.go index 65b4a227b..5f11b496c 100644 --- a/pkg/sentry/syscalls/linux/sys_epoll.go +++ b/pkg/sentry/syscalls/linux/sys_epoll.go @@ -20,8 +20,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/epoll" "gvisor.dev/gvisor/pkg/sentry/syscalls" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/syscalls/linux/sys_file.go b/pkg/sentry/syscalls/linux/sys_file.go index 9bc2445a5..c54735148 100644 --- a/pkg/sentry/syscalls/linux/sys_file.go +++ b/pkg/sentry/syscalls/linux/sys_file.go @@ -18,8 +18,8 @@ import ( "syscall" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/lock" "gvisor.dev/gvisor/pkg/sentry/fs/tmpfs" @@ -28,8 +28,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel/fasync" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/limits" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // fileOpAt performs an operation on the second last component in the path. diff --git a/pkg/sentry/syscalls/linux/sys_futex.go b/pkg/sentry/syscalls/linux/sys_futex.go index bde17a767..b68261f72 100644 --- a/pkg/sentry/syscalls/linux/sys_futex.go +++ b/pkg/sentry/syscalls/linux/sys_futex.go @@ -21,8 +21,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/kernel" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // futexWaitRestartBlock encapsulates the state required to restart futex(2) diff --git a/pkg/sentry/syscalls/linux/sys_getdents.go b/pkg/sentry/syscalls/linux/sys_getdents.go index 912cbe4ff..f66f4ffde 100644 --- a/pkg/sentry/syscalls/linux/sys_getdents.go +++ b/pkg/sentry/syscalls/linux/sys_getdents.go @@ -23,8 +23,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // Getdents implements linux syscall getdents(2) for 64bit systems. diff --git a/pkg/sentry/syscalls/linux/sys_mempolicy.go b/pkg/sentry/syscalls/linux/sys_mempolicy.go index f5a519d8a..ac934dc6f 100644 --- a/pkg/sentry/syscalls/linux/sys_mempolicy.go +++ b/pkg/sentry/syscalls/linux/sys_mempolicy.go @@ -20,8 +20,8 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // We unconditionally report a single NUMA node. This also means that our diff --git a/pkg/sentry/syscalls/linux/sys_mmap.go b/pkg/sentry/syscalls/linux/sys_mmap.go index 58a05b5bb..9959f6e61 100644 --- a/pkg/sentry/syscalls/linux/sys_mmap.go +++ b/pkg/sentry/syscalls/linux/sys_mmap.go @@ -22,8 +22,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/mm" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // Brk implements linux syscall brk(2). diff --git a/pkg/sentry/syscalls/linux/sys_mount.go b/pkg/sentry/syscalls/linux/sys_mount.go index 8c13e2d82..eb5ff48f5 100644 --- a/pkg/sentry/syscalls/linux/sys_mount.go +++ b/pkg/sentry/syscalls/linux/sys_mount.go @@ -19,8 +19,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // Mount implements Linux syscall mount(2). diff --git a/pkg/sentry/syscalls/linux/sys_pipe.go b/pkg/sentry/syscalls/linux/sys_pipe.go index 418d7fa5f..798344042 100644 --- a/pkg/sentry/syscalls/linux/sys_pipe.go +++ b/pkg/sentry/syscalls/linux/sys_pipe.go @@ -20,8 +20,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/pipe" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // pipe2 implements the actual system call with flags. diff --git a/pkg/sentry/syscalls/linux/sys_poll.go b/pkg/sentry/syscalls/linux/sys_poll.go index 2b2df989a..4f8762d7d 100644 --- a/pkg/sentry/syscalls/linux/sys_poll.go +++ b/pkg/sentry/syscalls/linux/sys_poll.go @@ -23,8 +23,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/limits" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/syscalls/linux/sys_random.go b/pkg/sentry/syscalls/linux/sys_random.go index bc4c588bf..c0aa0fd60 100644 --- a/pkg/sentry/syscalls/linux/sys_random.go +++ b/pkg/sentry/syscalls/linux/sys_random.go @@ -19,11 +19,11 @@ import ( "math" "gvisor.dev/gvisor/pkg/rand" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/safemem" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) const ( diff --git a/pkg/sentry/syscalls/linux/sys_read.go b/pkg/sentry/syscalls/linux/sys_read.go index cd31e0649..f9f594190 100644 --- a/pkg/sentry/syscalls/linux/sys_read.go +++ b/pkg/sentry/syscalls/linux/sys_read.go @@ -23,8 +23,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/socket" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/syscalls/linux/sys_rlimit.go b/pkg/sentry/syscalls/linux/sys_rlimit.go index 51e3f836b..e08c333d6 100644 --- a/pkg/sentry/syscalls/linux/sys_rlimit.go +++ b/pkg/sentry/syscalls/linux/sys_rlimit.go @@ -19,8 +19,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/limits" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // rlimit describes an implementation of 'struct rlimit', which may vary from diff --git a/pkg/sentry/syscalls/linux/sys_seccomp.go b/pkg/sentry/syscalls/linux/sys_seccomp.go index 18510ead8..5b7a66f4d 100644 --- a/pkg/sentry/syscalls/linux/sys_seccomp.go +++ b/pkg/sentry/syscalls/linux/sys_seccomp.go @@ -19,8 +19,8 @@ import ( "gvisor.dev/gvisor/pkg/bpf" "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // userSockFprog is equivalent to Linux's struct sock_fprog on amd64. diff --git a/pkg/sentry/syscalls/linux/sys_sem.go b/pkg/sentry/syscalls/linux/sys_sem.go index cde3b54e7..5f54f2456 100644 --- a/pkg/sentry/syscalls/linux/sys_sem.go +++ b/pkg/sentry/syscalls/linux/sys_sem.go @@ -22,8 +22,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) const opsMax = 500 // SEMOPM diff --git a/pkg/sentry/syscalls/linux/sys_signal.go b/pkg/sentry/syscalls/linux/sys_signal.go index fb6efd5d8..209be2990 100644 --- a/pkg/sentry/syscalls/linux/sys_signal.go +++ b/pkg/sentry/syscalls/linux/sys_signal.go @@ -23,8 +23,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/signalfd" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // "For a process to have permission to send a signal it must diff --git a/pkg/sentry/syscalls/linux/sys_socket.go b/pkg/sentry/syscalls/linux/sys_socket.go index cda517a81..2919228d0 100644 --- a/pkg/sentry/syscalls/linux/sys_socket.go +++ b/pkg/sentry/syscalls/linux/sys_socket.go @@ -26,9 +26,9 @@ import ( "gvisor.dev/gvisor/pkg/sentry/socket" "gvisor.dev/gvisor/pkg/sentry/socket/control" "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserr" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // minListenBacklog is the minimum reasonable backlog for listening sockets. diff --git a/pkg/sentry/syscalls/linux/sys_stat.go b/pkg/sentry/syscalls/linux/sys_stat.go index 69b17b799..c841abccb 100644 --- a/pkg/sentry/syscalls/linux/sys_stat.go +++ b/pkg/sentry/syscalls/linux/sys_stat.go @@ -19,8 +19,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // Stat implements linux syscall stat(2). diff --git a/pkg/sentry/syscalls/linux/sys_stat_amd64.go b/pkg/sentry/syscalls/linux/sys_stat_amd64.go index 58afb4a9a..75a567bd4 100644 --- a/pkg/sentry/syscalls/linux/sys_stat_amd64.go +++ b/pkg/sentry/syscalls/linux/sys_stat_amd64.go @@ -21,7 +21,7 @@ import ( "gvisor.dev/gvisor/pkg/binary" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // copyOutStat copies the attributes (sattr, uattr) to the struct stat at diff --git a/pkg/sentry/syscalls/linux/sys_stat_arm64.go b/pkg/sentry/syscalls/linux/sys_stat_arm64.go index 3e1251e0b..80c98d05c 100644 --- a/pkg/sentry/syscalls/linux/sys_stat_arm64.go +++ b/pkg/sentry/syscalls/linux/sys_stat_arm64.go @@ -21,7 +21,7 @@ import ( "gvisor.dev/gvisor/pkg/binary" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // copyOutStat copies the attributes (sattr, uattr) to the struct stat at diff --git a/pkg/sentry/syscalls/linux/sys_thread.go b/pkg/sentry/syscalls/linux/sys_thread.go index b47c3b5c4..0c9e2255d 100644 --- a/pkg/sentry/syscalls/linux/sys_thread.go +++ b/pkg/sentry/syscalls/linux/sys_thread.go @@ -24,8 +24,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/sched" "gvisor.dev/gvisor/pkg/sentry/loader" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) const ( diff --git a/pkg/sentry/syscalls/linux/sys_time.go b/pkg/sentry/syscalls/linux/sys_time.go index b887fa9d7..2d2aa0819 100644 --- a/pkg/sentry/syscalls/linux/sys_time.go +++ b/pkg/sentry/syscalls/linux/sys_time.go @@ -22,8 +22,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/kernel" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // The most significant 29 bits hold either a pid or a file descriptor. diff --git a/pkg/sentry/syscalls/linux/sys_timer.go b/pkg/sentry/syscalls/linux/sys_timer.go index d4134207b..432351917 100644 --- a/pkg/sentry/syscalls/linux/sys_timer.go +++ b/pkg/sentry/syscalls/linux/sys_timer.go @@ -20,8 +20,8 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) const nsecPerSec = int64(time.Second) diff --git a/pkg/sentry/syscalls/linux/sys_write.go b/pkg/sentry/syscalls/linux/sys_write.go index ad4b67806..aba892939 100644 --- a/pkg/sentry/syscalls/linux/sys_write.go +++ b/pkg/sentry/syscalls/linux/sys_write.go @@ -23,8 +23,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/socket" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/syscalls/linux/sys_xattr.go b/pkg/sentry/syscalls/linux/sys_xattr.go index 77deb8980..efb95555c 100644 --- a/pkg/sentry/syscalls/linux/sys_xattr.go +++ b/pkg/sentry/syscalls/linux/sys_xattr.go @@ -21,8 +21,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // GetXattr implements linux syscall getxattr(2). diff --git a/pkg/sentry/syscalls/linux/timespec.go b/pkg/sentry/syscalls/linux/timespec.go index 4ff8f9234..ddc3ee26e 100644 --- a/pkg/sentry/syscalls/linux/timespec.go +++ b/pkg/sentry/syscalls/linux/timespec.go @@ -19,8 +19,8 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // copyTimespecIn copies a Timespec from the untrusted app range to the kernel. diff --git a/pkg/sentry/unimpl/BUILD b/pkg/sentry/unimpl/BUILD index 370fa6ec5..5d4aa3a63 100644 --- a/pkg/sentry/unimpl/BUILD +++ b/pkg/sentry/unimpl/BUILD @@ -14,7 +14,7 @@ go_library( srcs = ["events.go"], visibility = ["//:sandbox"], deps = [ + "//pkg/context", "//pkg/log", - "//pkg/sentry/context", ], ) diff --git a/pkg/sentry/unimpl/events.go b/pkg/sentry/unimpl/events.go index 79b5de9e4..73ed9372f 100644 --- a/pkg/sentry/unimpl/events.go +++ b/pkg/sentry/unimpl/events.go @@ -17,8 +17,8 @@ package unimpl import ( + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/log" - "gvisor.dev/gvisor/pkg/sentry/context" ) // contextID is the events package's type for context.Context.Value keys. diff --git a/pkg/sentry/uniqueid/BUILD b/pkg/sentry/uniqueid/BUILD index e9c18f170..7467e6398 100644 --- a/pkg/sentry/uniqueid/BUILD +++ b/pkg/sentry/uniqueid/BUILD @@ -7,7 +7,7 @@ go_library( srcs = ["context.go"], visibility = ["//pkg/sentry:internal"], deps = [ - "//pkg/sentry/context", + "//pkg/context", "//pkg/sentry/socket/unix/transport", ], ) diff --git a/pkg/sentry/uniqueid/context.go b/pkg/sentry/uniqueid/context.go index 4e466d66d..1fb884a90 100644 --- a/pkg/sentry/uniqueid/context.go +++ b/pkg/sentry/uniqueid/context.go @@ -17,7 +17,7 @@ package uniqueid import ( - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" ) diff --git a/pkg/sentry/usermem/BUILD b/pkg/sentry/usermem/BUILD deleted file mode 100644 index c8322e29e..000000000 --- a/pkg/sentry/usermem/BUILD +++ /dev/null @@ -1,55 +0,0 @@ -load("//tools:defs.bzl", "go_library", "go_test") -load("//tools/go_generics:defs.bzl", "go_template_instance") - -package(licenses = ["notice"]) - -go_template_instance( - name = "addr_range", - out = "addr_range.go", - package = "usermem", - prefix = "Addr", - template = "//pkg/segment:generic_range", - types = { - "T": "Addr", - }, -) - -go_library( - name = "usermem", - srcs = [ - "access_type.go", - "addr.go", - "addr_range.go", - "addr_range_seq_unsafe.go", - "bytes_io.go", - "bytes_io_unsafe.go", - "usermem.go", - "usermem_arm64.go", - "usermem_unsafe.go", - "usermem_x86.go", - ], - visibility = ["//pkg/sentry:internal"], - deps = [ - "//pkg/atomicbitops", - "//pkg/binary", - "//pkg/log", - "//pkg/sentry/context", - "//pkg/sentry/safemem", - "//pkg/syserror", - ], -) - -go_test( - name = "usermem_test", - size = "small", - srcs = [ - "addr_range_seq_test.go", - "usermem_test.go", - ], - library = ":usermem", - deps = [ - "//pkg/sentry/context", - "//pkg/sentry/safemem", - "//pkg/syserror", - ], -) diff --git a/pkg/sentry/usermem/README.md b/pkg/sentry/usermem/README.md deleted file mode 100644 index f6d2137eb..000000000 --- a/pkg/sentry/usermem/README.md +++ /dev/null @@ -1,31 +0,0 @@ -This package defines primitives for sentry access to application memory. - -Major types: - -- The `IO` interface represents a virtual address space and provides I/O - methods on that address space. `IO` is the lowest-level primitive. The - primary implementation of the `IO` interface is `mm.MemoryManager`. - -- `IOSequence` represents a collection of individually-contiguous address - ranges in a `IO` that is operated on sequentially, analogous to Linux's - `struct iov_iter`. - -Major usage patterns: - -- Access to a task's virtual memory, subject to the application's memory - protections and while running on that task's goroutine, from a context that - is at or above the level of the `kernel` package (e.g. most syscall - implementations in `syscalls/linux`); use the `kernel.Task.Copy*` wrappers - defined in `kernel/task_usermem.go`. - -- Access to a task's virtual memory, from a context that is at or above the - level of the `kernel` package, but where any of the above constraints does - not hold (e.g. `PTRACE_POKEDATA`, which ignores application memory - protections); obtain the task's `mm.MemoryManager` by calling - `kernel.Task.MemoryManager`, and call its `IO` methods directly. - -- Access to a task's virtual memory, from a context that is below the level of - the `kernel` package (e.g. filesystem I/O); clients must pass I/O arguments - from higher layers, usually in the form of an `IOSequence`. The - `kernel.Task.SingleIOSequence` and `kernel.Task.IovecsIOSequence` functions - in `kernel/task_usermem.go` are convenience functions for doing so. diff --git a/pkg/sentry/usermem/access_type.go b/pkg/sentry/usermem/access_type.go deleted file mode 100644 index 9c1742a59..000000000 --- a/pkg/sentry/usermem/access_type.go +++ /dev/null @@ -1,128 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -package usermem - -import ( - "syscall" -) - -// AccessType specifies memory access types. This is used for -// setting mapping permissions, as well as communicating faults. -// -// +stateify savable -type AccessType struct { - // Read is read access. - Read bool - - // Write is write access. - Write bool - - // Execute is executable access. - Execute bool -} - -// String returns a pretty representation of access. This looks like the -// familiar r-x, rw-, etc. and can be relied on as such. -func (a AccessType) String() string { - bits := [3]byte{'-', '-', '-'} - if a.Read { - bits[0] = 'r' - } - if a.Write { - bits[1] = 'w' - } - if a.Execute { - bits[2] = 'x' - } - return string(bits[:]) -} - -// Any returns true iff at least one of Read, Write or Execute is true. -func (a AccessType) Any() bool { - return a.Read || a.Write || a.Execute -} - -// Prot returns the system prot (syscall.PROT_READ, etc.) for this access. -func (a AccessType) Prot() int { - var prot int - if a.Read { - prot |= syscall.PROT_READ - } - if a.Write { - prot |= syscall.PROT_WRITE - } - if a.Execute { - prot |= syscall.PROT_EXEC - } - return prot -} - -// SupersetOf returns true iff the access types in a are a superset of the -// access types in other. -func (a AccessType) SupersetOf(other AccessType) bool { - if !a.Read && other.Read { - return false - } - if !a.Write && other.Write { - return false - } - if !a.Execute && other.Execute { - return false - } - return true -} - -// Intersect returns the access types set in both a and other. -func (a AccessType) Intersect(other AccessType) AccessType { - return AccessType{ - Read: a.Read && other.Read, - Write: a.Write && other.Write, - Execute: a.Execute && other.Execute, - } -} - -// Union returns the access types set in either a or other. -func (a AccessType) Union(other AccessType) AccessType { - return AccessType{ - Read: a.Read || other.Read, - Write: a.Write || other.Write, - Execute: a.Execute || other.Execute, - } -} - -// Effective returns the set of effective access types allowed by a, even if -// some types are not explicitly allowed. -func (a AccessType) Effective() AccessType { - // In Linux, Write and Execute access generally imply Read access. See - // mm/mmap.c:protection_map. - // - // The notable exception is get_user_pages, which only checks against - // the original vma flags. That said, most user memory accesses do not - // use GUP. - if a.Write || a.Execute { - a.Read = true - } - return a -} - -// Convenient access types. -var ( - NoAccess = AccessType{} - Read = AccessType{Read: true} - Write = AccessType{Write: true} - Execute = AccessType{Execute: true} - ReadWrite = AccessType{Read: true, Write: true} - AnyAccess = AccessType{Read: true, Write: true, Execute: true} -) diff --git a/pkg/sentry/usermem/addr.go b/pkg/sentry/usermem/addr.go deleted file mode 100644 index e79210804..000000000 --- a/pkg/sentry/usermem/addr.go +++ /dev/null @@ -1,108 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -package usermem - -import ( - "fmt" -) - -// Addr represents a generic virtual address. -// -// +stateify savable -type Addr uintptr - -// AddLength adds the given length to start and returns the result. ok is true -// iff adding the length did not overflow the range of Addr. -// -// Note: This function is usually used to get the end of an address range -// defined by its start address and length. Since the resulting end is -// exclusive, end == 0 is technically valid, and corresponds to a range that -// extends to the end of the address space, but ok will be false. This isn't -// expected to ever come up in practice. -func (v Addr) AddLength(length uint64) (end Addr, ok bool) { - end = v + Addr(length) - // The second half of the following check is needed in case uintptr is - // smaller than 64 bits. - ok = end >= v && length <= uint64(^Addr(0)) - return -} - -// RoundDown returns the address rounded down to the nearest page boundary. -func (v Addr) RoundDown() Addr { - return v & ^Addr(PageSize-1) -} - -// RoundUp returns the address rounded up to the nearest page boundary. ok is -// true iff rounding up did not wrap around. -func (v Addr) RoundUp() (addr Addr, ok bool) { - addr = Addr(v + PageSize - 1).RoundDown() - ok = addr >= v - return -} - -// MustRoundUp is equivalent to RoundUp, but panics if rounding up wraps -// around. -func (v Addr) MustRoundUp() Addr { - addr, ok := v.RoundUp() - if !ok { - panic(fmt.Sprintf("usermem.Addr(%d).RoundUp() wraps", v)) - } - return addr -} - -// HugeRoundDown returns the address rounded down to the nearest huge page -// boundary. -func (v Addr) HugeRoundDown() Addr { - return v & ^Addr(HugePageSize-1) -} - -// HugeRoundUp returns the address rounded up to the nearest huge page boundary. -// ok is true iff rounding up did not wrap around. -func (v Addr) HugeRoundUp() (addr Addr, ok bool) { - addr = Addr(v + HugePageSize - 1).HugeRoundDown() - ok = addr >= v - return -} - -// PageOffset returns the offset of v into the current page. -func (v Addr) PageOffset() uint64 { - return uint64(v & Addr(PageSize-1)) -} - -// IsPageAligned returns true if v.PageOffset() == 0. -func (v Addr) IsPageAligned() bool { - return v.PageOffset() == 0 -} - -// AddrRange is a range of Addrs. -// -// type AddrRange - -// ToRange returns [v, v+length). -func (v Addr) ToRange(length uint64) (AddrRange, bool) { - end, ok := v.AddLength(length) - return AddrRange{v, end}, ok -} - -// IsPageAligned returns true if ar.Start.IsPageAligned() and -// ar.End.IsPageAligned(). -func (ar AddrRange) IsPageAligned() bool { - return ar.Start.IsPageAligned() && ar.End.IsPageAligned() -} - -// String implements fmt.Stringer.String. -func (ar AddrRange) String() string { - return fmt.Sprintf("[%#x, %#x)", ar.Start, ar.End) -} diff --git a/pkg/sentry/usermem/addr_range_seq_test.go b/pkg/sentry/usermem/addr_range_seq_test.go deleted file mode 100644 index 82f735026..000000000 --- a/pkg/sentry/usermem/addr_range_seq_test.go +++ /dev/null @@ -1,197 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -package usermem - -import ( - "testing" -) - -var addrRangeSeqTests = []struct { - desc string - ranges []AddrRange -}{ - { - desc: "Empty sequence", - }, - { - desc: "Single empty AddrRange", - ranges: []AddrRange{ - {0x10, 0x10}, - }, - }, - { - desc: "Single non-empty AddrRange of length 1", - ranges: []AddrRange{ - {0x10, 0x11}, - }, - }, - { - desc: "Single non-empty AddrRange of length 2", - ranges: []AddrRange{ - {0x10, 0x12}, - }, - }, - { - desc: "Multiple non-empty AddrRanges", - ranges: []AddrRange{ - {0x10, 0x11}, - {0x20, 0x22}, - }, - }, - { - desc: "Multiple AddrRanges including empty AddrRanges", - ranges: []AddrRange{ - {0x10, 0x10}, - {0x20, 0x20}, - {0x30, 0x33}, - {0x40, 0x44}, - {0x50, 0x50}, - {0x60, 0x60}, - {0x70, 0x77}, - {0x80, 0x88}, - {0x90, 0x90}, - {0xa0, 0xa0}, - }, - }, -} - -func testAddrRangeSeqEqualityWithTailIteration(t *testing.T, ars AddrRangeSeq, wantRanges []AddrRange) { - var wantLen int64 - for _, ar := range wantRanges { - wantLen += int64(ar.Length()) - } - - var i int - for !ars.IsEmpty() { - if gotLen := ars.NumBytes(); gotLen != wantLen { - t.Errorf("Iteration %d: %v.NumBytes(): got %d, wanted %d", i, ars, gotLen, wantLen) - } - if gotN, wantN := ars.NumRanges(), len(wantRanges)-i; gotN != wantN { - t.Errorf("Iteration %d: %v.NumRanges(): got %d, wanted %d", i, ars, gotN, wantN) - } - got := ars.Head() - if i >= len(wantRanges) { - t.Errorf("Iteration %d: %v.Head(): got %s, wanted ", i, ars, got) - } else if want := wantRanges[i]; got != want { - t.Errorf("Iteration %d: %v.Head(): got %s, wanted %s", i, ars, got, want) - } - ars = ars.Tail() - wantLen -= int64(got.Length()) - i++ - } - if gotLen := ars.NumBytes(); gotLen != 0 || wantLen != 0 { - t.Errorf("Iteration %d: %v.NumBytes(): got %d, wanted %d (which should be 0)", i, ars, gotLen, wantLen) - } - if gotN := ars.NumRanges(); gotN != 0 { - t.Errorf("Iteration %d: %v.NumRanges(): got %d, wanted 0", i, ars, gotN) - } -} - -func TestAddrRangeSeqTailIteration(t *testing.T) { - for _, test := range addrRangeSeqTests { - t.Run(test.desc, func(t *testing.T) { - testAddrRangeSeqEqualityWithTailIteration(t, AddrRangeSeqFromSlice(test.ranges), test.ranges) - }) - } -} - -func TestAddrRangeSeqDropFirstEmpty(t *testing.T) { - var ars AddrRangeSeq - if got, want := ars.DropFirst(1), ars; got != want { - t.Errorf("%v.DropFirst(1): got %v, wanted %v", ars, got, want) - } -} - -func TestAddrRangeSeqDropSingleByteIteration(t *testing.T) { - // Tests AddrRangeSeq iteration using Head/DropFirst, simulating - // I/O-per-AddrRange. - for _, test := range addrRangeSeqTests { - t.Run(test.desc, func(t *testing.T) { - // Figure out what AddrRanges we expect to see. - var wantLen int64 - var wantRanges []AddrRange - for _, ar := range test.ranges { - wantLen += int64(ar.Length()) - wantRanges = append(wantRanges, ar) - if ar.Length() == 0 { - // We "do" 0 bytes of I/O and then call DropFirst(0), - // advancing to the next AddrRange. - continue - } - // Otherwise we "do" 1 byte of I/O and then call DropFirst(1), - // advancing the AddrRange by 1 byte, or to the next AddrRange - // if this one is exhausted. - for ar.Start++; ar.Length() != 0; ar.Start++ { - wantRanges = append(wantRanges, ar) - } - } - t.Logf("Expected AddrRanges: %s (%d bytes)", wantRanges, wantLen) - - ars := AddrRangeSeqFromSlice(test.ranges) - var i int - for !ars.IsEmpty() { - if gotLen := ars.NumBytes(); gotLen != wantLen { - t.Errorf("Iteration %d: %v.NumBytes(): got %d, wanted %d", i, ars, gotLen, wantLen) - } - got := ars.Head() - if i >= len(wantRanges) { - t.Errorf("Iteration %d: %v.Head(): got %s, wanted ", i, ars, got) - } else if want := wantRanges[i]; got != want { - t.Errorf("Iteration %d: %v.Head(): got %s, wanted %s", i, ars, got, want) - } - if got.Length() == 0 { - ars = ars.DropFirst(0) - } else { - ars = ars.DropFirst(1) - wantLen-- - } - i++ - } - if gotLen := ars.NumBytes(); gotLen != 0 || wantLen != 0 { - t.Errorf("Iteration %d: %v.NumBytes(): got %d, wanted %d (which should be 0)", i, ars, gotLen, wantLen) - } - }) - } -} - -func TestAddrRangeSeqTakeFirstEmpty(t *testing.T) { - var ars AddrRangeSeq - if got, want := ars.TakeFirst(1), ars; got != want { - t.Errorf("%v.TakeFirst(1): got %v, wanted %v", ars, got, want) - } -} - -func TestAddrRangeSeqTakeFirst(t *testing.T) { - ranges := []AddrRange{ - {0x10, 0x11}, - {0x20, 0x22}, - {0x30, 0x30}, - {0x40, 0x44}, - {0x50, 0x55}, - {0x60, 0x60}, - {0x70, 0x77}, - } - ars := AddrRangeSeqFromSlice(ranges).TakeFirst(5) - want := []AddrRange{ - {0x10, 0x11}, // +1 byte (total 1 byte), not truncated - {0x20, 0x22}, // +2 bytes (total 3 bytes), not truncated - {0x30, 0x30}, // +0 bytes (total 3 bytes), no change - {0x40, 0x42}, // +2 bytes (total 5 bytes), partially truncated - {0x50, 0x50}, // +0 bytes (total 5 bytes), fully truncated - {0x60, 0x60}, // +0 bytes (total 5 bytes), "fully truncated" (no change) - {0x70, 0x70}, // +0 bytes (total 5 bytes), fully truncated - } - testAddrRangeSeqEqualityWithTailIteration(t, ars, want) -} diff --git a/pkg/sentry/usermem/addr_range_seq_unsafe.go b/pkg/sentry/usermem/addr_range_seq_unsafe.go deleted file mode 100644 index c09337c15..000000000 --- a/pkg/sentry/usermem/addr_range_seq_unsafe.go +++ /dev/null @@ -1,277 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -package usermem - -import ( - "bytes" - "fmt" - "reflect" - "unsafe" -) - -// An AddrRangeSeq represents a sequence of AddrRanges. -// -// AddrRangeSeqs are immutable and may be copied by value. The zero value of -// AddrRangeSeq represents an empty sequence. -// -// An AddrRangeSeq may contain AddrRanges with a length of 0. This is necessary -// since zero-length AddrRanges are significant to MM bounds checks. -type AddrRangeSeq struct { - // If length is 0, then the AddrRangeSeq represents no AddrRanges. - // Invariants: data == 0; offset == 0; limit == 0. - // - // If length is 1, then the AddrRangeSeq represents the single - // AddrRange{offset, offset+limit}. Invariants: data == 0. - // - // Otherwise, length >= 2, and the AddrRangeSeq represents the `length` - // AddrRanges in the array of AddrRanges starting at address `data`, - // starting at `offset` bytes into the first AddrRange and limited to the - // following `limit` bytes. (AddrRanges after `limit` are still iterated, - // but are truncated to a length of 0.) Invariants: data != 0; offset <= - // data[0].Length(); limit > 0; offset+limit <= the combined length of all - // AddrRanges in the array. - data unsafe.Pointer - length int - offset Addr - limit Addr -} - -// AddrRangeSeqOf returns an AddrRangeSeq representing the single AddrRange ar. -func AddrRangeSeqOf(ar AddrRange) AddrRangeSeq { - return AddrRangeSeq{ - length: 1, - offset: ar.Start, - limit: ar.Length(), - } -} - -// AddrRangeSeqFromSlice returns an AddrRangeSeq representing all AddrRanges in -// slice. -// -// Whether the returned AddrRangeSeq shares memory with slice is unspecified; -// clients should avoid mutating slices passed to AddrRangeSeqFromSlice. -// -// Preconditions: The combined length of all AddrRanges in slice <= -// math.MaxInt64. -func AddrRangeSeqFromSlice(slice []AddrRange) AddrRangeSeq { - var limit int64 - for _, ar := range slice { - len64 := int64(ar.Length()) - if len64 < 0 { - panic(fmt.Sprintf("Length of AddrRange %v overflows int64", ar)) - } - sum := limit + len64 - if sum < limit { - panic(fmt.Sprintf("Total length of AddrRanges %v overflows int64", slice)) - } - limit = sum - } - return addrRangeSeqFromSliceLimited(slice, limit) -} - -// Preconditions: The combined length of all AddrRanges in slice <= limit. -// limit >= 0. If len(slice) != 0, then limit > 0. -func addrRangeSeqFromSliceLimited(slice []AddrRange, limit int64) AddrRangeSeq { - switch len(slice) { - case 0: - return AddrRangeSeq{} - case 1: - return AddrRangeSeq{ - length: 1, - offset: slice[0].Start, - limit: Addr(limit), - } - default: - return AddrRangeSeq{ - data: unsafe.Pointer(&slice[0]), - length: len(slice), - limit: Addr(limit), - } - } -} - -// IsEmpty returns true if ars.NumRanges() == 0. -// -// Note that since AddrRangeSeq may contain AddrRanges with a length of zero, -// an AddrRange representing 0 bytes (AddrRangeSeq.NumBytes() == 0) is not -// necessarily empty. -func (ars AddrRangeSeq) IsEmpty() bool { - return ars.length == 0 -} - -// NumRanges returns the number of AddrRanges in ars. -func (ars AddrRangeSeq) NumRanges() int { - return ars.length -} - -// NumBytes returns the number of bytes represented by ars. -func (ars AddrRangeSeq) NumBytes() int64 { - return int64(ars.limit) -} - -// Head returns the first AddrRange in ars. -// -// Preconditions: !ars.IsEmpty(). -func (ars AddrRangeSeq) Head() AddrRange { - if ars.length == 0 { - panic("empty AddrRangeSeq") - } - if ars.length == 1 { - return AddrRange{ars.offset, ars.offset + ars.limit} - } - ar := *(*AddrRange)(ars.data) - ar.Start += ars.offset - if ar.Length() > ars.limit { - ar.End = ar.Start + ars.limit - } - return ar -} - -// Tail returns an AddrRangeSeq consisting of all AddrRanges in ars after the -// first. -// -// Preconditions: !ars.IsEmpty(). -func (ars AddrRangeSeq) Tail() AddrRangeSeq { - if ars.length == 0 { - panic("empty AddrRangeSeq") - } - if ars.length == 1 { - return AddrRangeSeq{} - } - return ars.externalTail() -} - -// Preconditions: ars.length >= 2. -func (ars AddrRangeSeq) externalTail() AddrRangeSeq { - headLen := (*AddrRange)(ars.data).Length() - ars.offset - var tailLimit int64 - if ars.limit > headLen { - tailLimit = int64(ars.limit - headLen) - } - var extSlice []AddrRange - extSliceHdr := (*reflect.SliceHeader)(unsafe.Pointer(&extSlice)) - extSliceHdr.Data = uintptr(ars.data) - extSliceHdr.Len = ars.length - extSliceHdr.Cap = ars.length - return addrRangeSeqFromSliceLimited(extSlice[1:], tailLimit) -} - -// DropFirst returns an AddrRangeSeq equivalent to ars, but with the first n -// bytes omitted. If n > ars.NumBytes(), DropFirst returns an empty -// AddrRangeSeq. -// -// If !ars.IsEmpty() and ars.Head().Length() == 0, DropFirst will always omit -// at least ars.Head(), even if n == 0. This guarantees that the basic pattern -// of: -// -// for !ars.IsEmpty() { -// n, err = doIOWith(ars.Head()) -// if err != nil { -// return err -// } -// ars = ars.DropFirst(n) -// } -// -// works even in the presence of zero-length AddrRanges. -// -// Preconditions: n >= 0. -func (ars AddrRangeSeq) DropFirst(n int) AddrRangeSeq { - if n < 0 { - panic(fmt.Sprintf("invalid n: %d", n)) - } - return ars.DropFirst64(int64(n)) -} - -// DropFirst64 is equivalent to DropFirst but takes an int64. -func (ars AddrRangeSeq) DropFirst64(n int64) AddrRangeSeq { - if n < 0 { - panic(fmt.Sprintf("invalid n: %d", n)) - } - if Addr(n) > ars.limit { - return AddrRangeSeq{} - } - // Handle initial empty AddrRange. - switch ars.length { - case 0: - return AddrRangeSeq{} - case 1: - if ars.limit == 0 { - return AddrRangeSeq{} - } - default: - if rawHeadLen := (*AddrRange)(ars.data).Length(); ars.offset == rawHeadLen { - ars = ars.externalTail() - } - } - for n != 0 { - // Calling ars.Head() here is surprisingly expensive, so inline getting - // the head's length. - var headLen Addr - if ars.length == 1 { - headLen = ars.limit - } else { - headLen = (*AddrRange)(ars.data).Length() - ars.offset - } - if Addr(n) < headLen { - // Dropping ends partway through the head AddrRange. - ars.offset += Addr(n) - ars.limit -= Addr(n) - return ars - } - n -= int64(headLen) - ars = ars.Tail() - } - return ars -} - -// TakeFirst returns an AddrRangeSeq equivalent to ars, but iterating at most n -// bytes. TakeFirst never removes AddrRanges from ars; AddrRanges beyond the -// first n bytes are reduced to a length of zero, but will still be iterated. -// -// Preconditions: n >= 0. -func (ars AddrRangeSeq) TakeFirst(n int) AddrRangeSeq { - if n < 0 { - panic(fmt.Sprintf("invalid n: %d", n)) - } - return ars.TakeFirst64(int64(n)) -} - -// TakeFirst64 is equivalent to TakeFirst but takes an int64. -func (ars AddrRangeSeq) TakeFirst64(n int64) AddrRangeSeq { - if n < 0 { - panic(fmt.Sprintf("invalid n: %d", n)) - } - if ars.limit > Addr(n) { - ars.limit = Addr(n) - } - return ars -} - -// String implements fmt.Stringer.String. -func (ars AddrRangeSeq) String() string { - // This is deliberately chosen to be the same as fmt's automatic stringer - // for []AddrRange. - var buf bytes.Buffer - buf.WriteByte('[') - var sep string - for !ars.IsEmpty() { - buf.WriteString(sep) - sep = " " - buf.WriteString(ars.Head().String()) - ars = ars.Tail() - } - buf.WriteByte(']') - return buf.String() -} diff --git a/pkg/sentry/usermem/bytes_io.go b/pkg/sentry/usermem/bytes_io.go deleted file mode 100644 index 7898851b3..000000000 --- a/pkg/sentry/usermem/bytes_io.go +++ /dev/null @@ -1,141 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -package usermem - -import ( - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/safemem" - "gvisor.dev/gvisor/pkg/syserror" -) - -const maxInt = int(^uint(0) >> 1) - -// BytesIO implements IO using a byte slice. Addresses are interpreted as -// offsets into the slice. Reads and writes beyond the end of the slice return -// EFAULT. -type BytesIO struct { - Bytes []byte -} - -// CopyOut implements IO.CopyOut. -func (b *BytesIO) CopyOut(ctx context.Context, addr Addr, src []byte, opts IOOpts) (int, error) { - rngN, rngErr := b.rangeCheck(addr, len(src)) - if rngN == 0 { - return 0, rngErr - } - return copy(b.Bytes[int(addr):], src[:rngN]), rngErr -} - -// CopyIn implements IO.CopyIn. -func (b *BytesIO) CopyIn(ctx context.Context, addr Addr, dst []byte, opts IOOpts) (int, error) { - rngN, rngErr := b.rangeCheck(addr, len(dst)) - if rngN == 0 { - return 0, rngErr - } - return copy(dst[:rngN], b.Bytes[int(addr):]), rngErr -} - -// ZeroOut implements IO.ZeroOut. -func (b *BytesIO) ZeroOut(ctx context.Context, addr Addr, toZero int64, opts IOOpts) (int64, error) { - if toZero > int64(maxInt) { - return 0, syserror.EINVAL - } - rngN, rngErr := b.rangeCheck(addr, int(toZero)) - if rngN == 0 { - return 0, rngErr - } - zeroSlice := b.Bytes[int(addr) : int(addr)+rngN] - for i := range zeroSlice { - zeroSlice[i] = 0 - } - return int64(rngN), rngErr -} - -// CopyOutFrom implements IO.CopyOutFrom. -func (b *BytesIO) CopyOutFrom(ctx context.Context, ars AddrRangeSeq, src safemem.Reader, opts IOOpts) (int64, error) { - dsts, rngErr := b.blocksFromAddrRanges(ars) - n, err := src.ReadToBlocks(dsts) - if err != nil { - return int64(n), err - } - return int64(n), rngErr -} - -// CopyInTo implements IO.CopyInTo. -func (b *BytesIO) CopyInTo(ctx context.Context, ars AddrRangeSeq, dst safemem.Writer, opts IOOpts) (int64, error) { - srcs, rngErr := b.blocksFromAddrRanges(ars) - n, err := dst.WriteFromBlocks(srcs) - if err != nil { - return int64(n), err - } - return int64(n), rngErr -} - -func (b *BytesIO) rangeCheck(addr Addr, length int) (int, error) { - if length == 0 { - return 0, nil - } - if length < 0 { - return 0, syserror.EINVAL - } - max := Addr(len(b.Bytes)) - if addr >= max { - return 0, syserror.EFAULT - } - end, ok := addr.AddLength(uint64(length)) - if !ok || end > max { - return int(max - addr), syserror.EFAULT - } - return length, nil -} - -func (b *BytesIO) blocksFromAddrRanges(ars AddrRangeSeq) (safemem.BlockSeq, error) { - switch ars.NumRanges() { - case 0: - return safemem.BlockSeq{}, nil - case 1: - block, err := b.blockFromAddrRange(ars.Head()) - return safemem.BlockSeqOf(block), err - default: - blocks := make([]safemem.Block, 0, ars.NumRanges()) - for !ars.IsEmpty() { - block, err := b.blockFromAddrRange(ars.Head()) - if block.Len() != 0 { - blocks = append(blocks, block) - } - if err != nil { - return safemem.BlockSeqFromSlice(blocks), err - } - ars = ars.Tail() - } - return safemem.BlockSeqFromSlice(blocks), nil - } -} - -func (b *BytesIO) blockFromAddrRange(ar AddrRange) (safemem.Block, error) { - n, err := b.rangeCheck(ar.Start, int(ar.Length())) - if n == 0 { - return safemem.Block{}, err - } - return safemem.BlockFromSafeSlice(b.Bytes[int(ar.Start) : int(ar.Start)+n]), err -} - -// BytesIOSequence returns an IOSequence representing the given byte slice. -func BytesIOSequence(buf []byte) IOSequence { - return IOSequence{ - IO: &BytesIO{buf}, - Addrs: AddrRangeSeqOf(AddrRange{0, Addr(len(buf))}), - } -} diff --git a/pkg/sentry/usermem/bytes_io_unsafe.go b/pkg/sentry/usermem/bytes_io_unsafe.go deleted file mode 100644 index fca5952f4..000000000 --- a/pkg/sentry/usermem/bytes_io_unsafe.go +++ /dev/null @@ -1,47 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -package usermem - -import ( - "sync/atomic" - "unsafe" - - "gvisor.dev/gvisor/pkg/atomicbitops" - "gvisor.dev/gvisor/pkg/sentry/context" -) - -// SwapUint32 implements IO.SwapUint32. -func (b *BytesIO) SwapUint32(ctx context.Context, addr Addr, new uint32, opts IOOpts) (uint32, error) { - if _, rngErr := b.rangeCheck(addr, 4); rngErr != nil { - return 0, rngErr - } - return atomic.SwapUint32((*uint32)(unsafe.Pointer(&b.Bytes[int(addr)])), new), nil -} - -// CompareAndSwapUint32 implements IO.CompareAndSwapUint32. -func (b *BytesIO) CompareAndSwapUint32(ctx context.Context, addr Addr, old, new uint32, opts IOOpts) (uint32, error) { - if _, rngErr := b.rangeCheck(addr, 4); rngErr != nil { - return 0, rngErr - } - return atomicbitops.CompareAndSwapUint32((*uint32)(unsafe.Pointer(&b.Bytes[int(addr)])), old, new), nil -} - -// LoadUint32 implements IO.LoadUint32. -func (b *BytesIO) LoadUint32(ctx context.Context, addr Addr, opts IOOpts) (uint32, error) { - if _, err := b.rangeCheck(addr, 4); err != nil { - return 0, err - } - return atomic.LoadUint32((*uint32)(unsafe.Pointer(&b.Bytes[int(addr)]))), nil -} diff --git a/pkg/sentry/usermem/usermem.go b/pkg/sentry/usermem/usermem.go deleted file mode 100644 index 7b1f312b1..000000000 --- a/pkg/sentry/usermem/usermem.go +++ /dev/null @@ -1,597 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -// Package usermem governs access to user memory. -package usermem - -import ( - "bytes" - "errors" - "io" - "strconv" - - "gvisor.dev/gvisor/pkg/binary" - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/safemem" - "gvisor.dev/gvisor/pkg/syserror" -) - -// IO provides access to the contents of a virtual memory space. -// -// FIXME(b/38173783): Implementations of IO cannot expect ctx to contain any -// meaningful data. -type IO interface { - // CopyOut copies len(src) bytes from src to the memory mapped at addr. It - // returns the number of bytes copied. If the number of bytes copied is < - // len(src), it returns a non-nil error explaining why. - // - // Preconditions: The caller must not hold mm.MemoryManager.mappingMu or - // any following locks in the lock order. - // - // Postconditions: CopyOut does not retain src. - CopyOut(ctx context.Context, addr Addr, src []byte, opts IOOpts) (int, error) - - // CopyIn copies len(dst) bytes from the memory mapped at addr to dst. - // It returns the number of bytes copied. If the number of bytes copied is - // < len(dst), it returns a non-nil error explaining why. - // - // Preconditions: The caller must not hold mm.MemoryManager.mappingMu or - // any following locks in the lock order. - // - // Postconditions: CopyIn does not retain dst. - CopyIn(ctx context.Context, addr Addr, dst []byte, opts IOOpts) (int, error) - - // ZeroOut sets toZero bytes to 0, starting at addr. It returns the number - // of bytes zeroed. If the number of bytes zeroed is < toZero, it returns a - // non-nil error explaining why. - // - // Preconditions: The caller must not hold mm.MemoryManager.mappingMu or - // any following locks in the lock order. toZero >= 0. - ZeroOut(ctx context.Context, addr Addr, toZero int64, opts IOOpts) (int64, error) - - // CopyOutFrom copies ars.NumBytes() bytes from src to the memory mapped at - // ars. It returns the number of bytes copied, which may be less than the - // number of bytes read from src if copying fails. CopyOutFrom may return a - // partial copy without an error iff src.ReadToBlocks returns a partial - // read without an error. - // - // CopyOutFrom calls src.ReadToBlocks at most once. - // - // Preconditions: The caller must not hold mm.MemoryManager.mappingMu or - // any following locks in the lock order. src.ReadToBlocks must not block - // on mm.MemoryManager.activeMu or any preceding locks in the lock order. - CopyOutFrom(ctx context.Context, ars AddrRangeSeq, src safemem.Reader, opts IOOpts) (int64, error) - - // CopyInTo copies ars.NumBytes() bytes from the memory mapped at ars to - // dst. It returns the number of bytes copied. CopyInTo may return a - // partial copy without an error iff dst.WriteFromBlocks returns a partial - // write without an error. - // - // CopyInTo calls dst.WriteFromBlocks at most once. - // - // Preconditions: The caller must not hold mm.MemoryManager.mappingMu or - // any following locks in the lock order. dst.WriteFromBlocks must not - // block on mm.MemoryManager.activeMu or any preceding locks in the lock - // order. - CopyInTo(ctx context.Context, ars AddrRangeSeq, dst safemem.Writer, opts IOOpts) (int64, error) - - // TODO(jamieliu): The requirement that CopyOutFrom/CopyInTo call src/dst - // at most once, which is unnecessary in most cases, forces implementations - // to gather safemem.Blocks into a single slice to pass to src/dst. Add - // CopyOutFromIter/CopyInToIter, which relaxes this restriction, to avoid - // this allocation. - - // SwapUint32 atomically sets the uint32 value at addr to new and - // returns the previous value. - // - // Preconditions: The caller must not hold mm.MemoryManager.mappingMu or - // any following locks in the lock order. addr must be aligned to a 4-byte - // boundary. - SwapUint32(ctx context.Context, addr Addr, new uint32, opts IOOpts) (uint32, error) - - // CompareAndSwapUint32 atomically compares the uint32 value at addr to - // old; if they are equal, the value in memory is replaced by new. In - // either case, the previous value stored in memory is returned. - // - // Preconditions: The caller must not hold mm.MemoryManager.mappingMu or - // any following locks in the lock order. addr must be aligned to a 4-byte - // boundary. - CompareAndSwapUint32(ctx context.Context, addr Addr, old, new uint32, opts IOOpts) (uint32, error) - - // LoadUint32 atomically loads the uint32 value at addr and returns it. - // - // Preconditions: The caller must not hold mm.MemoryManager.mappingMu or - // any following locks in the lock order. addr must be aligned to a 4-byte - // boundary. - LoadUint32(ctx context.Context, addr Addr, opts IOOpts) (uint32, error) -} - -// IOOpts contains options applicable to all IO methods. -type IOOpts struct { - // If IgnorePermissions is true, application-defined memory protections set - // by mmap(2) or mprotect(2) will be ignored. (Memory protections required - // by the target of the mapping are never ignored.) - IgnorePermissions bool - - // If AddressSpaceActive is true, the IO implementation may assume that it - // has an active AddressSpace and can therefore use AddressSpace copying - // without performing activation. See mm/io.go for details. - AddressSpaceActive bool -} - -// IOReadWriter is an io.ReadWriter that reads from / writes to addresses -// starting at addr in IO. The preconditions that apply to IO.CopyIn and -// IO.CopyOut also apply to IOReadWriter.Read and IOReadWriter.Write -// respectively. -type IOReadWriter struct { - Ctx context.Context - IO IO - Addr Addr - Opts IOOpts -} - -// Read implements io.Reader.Read. -// -// Note that an address space does not have an "end of file", so Read can only -// return io.EOF if IO.CopyIn returns io.EOF. Attempts to read unmapped or -// unreadable memory, or beyond the end of the address space, should return -// EFAULT. -func (rw *IOReadWriter) Read(dst []byte) (int, error) { - n, err := rw.IO.CopyIn(rw.Ctx, rw.Addr, dst, rw.Opts) - end, ok := rw.Addr.AddLength(uint64(n)) - if ok { - rw.Addr = end - } else { - // Disallow wraparound. - rw.Addr = ^Addr(0) - if err != nil { - err = syserror.EFAULT - } - } - return n, err -} - -// Writer implements io.Writer.Write. -func (rw *IOReadWriter) Write(src []byte) (int, error) { - n, err := rw.IO.CopyOut(rw.Ctx, rw.Addr, src, rw.Opts) - end, ok := rw.Addr.AddLength(uint64(n)) - if ok { - rw.Addr = end - } else { - // Disallow wraparound. - rw.Addr = ^Addr(0) - if err != nil { - err = syserror.EFAULT - } - } - return n, err -} - -// CopyObjectOut copies a fixed-size value or slice of fixed-size values from -// src to the memory mapped at addr in uio. It returns the number of bytes -// copied. -// -// CopyObjectOut must use reflection to encode src; performance-sensitive -// clients should do encoding manually and use uio.CopyOut directly. -// -// Preconditions: As for IO.CopyOut. -func CopyObjectOut(ctx context.Context, uio IO, addr Addr, src interface{}, opts IOOpts) (int, error) { - w := &IOReadWriter{ - Ctx: ctx, - IO: uio, - Addr: addr, - Opts: opts, - } - // Allocate a byte slice the size of the object being marshaled. This - // adds an extra reflection call, but avoids needing to grow the slice - // during encoding, which can result in many heap-allocated slices. - b := make([]byte, 0, binary.Size(src)) - return w.Write(binary.Marshal(b, ByteOrder, src)) -} - -// CopyObjectIn copies a fixed-size value or slice of fixed-size values from -// the memory mapped at addr in uio to dst. It returns the number of bytes -// copied. -// -// CopyObjectIn must use reflection to decode dst; performance-sensitive -// clients should use uio.CopyIn directly and do decoding manually. -// -// Preconditions: As for IO.CopyIn. -func CopyObjectIn(ctx context.Context, uio IO, addr Addr, dst interface{}, opts IOOpts) (int, error) { - r := &IOReadWriter{ - Ctx: ctx, - IO: uio, - Addr: addr, - Opts: opts, - } - buf := make([]byte, binary.Size(dst)) - if _, err := io.ReadFull(r, buf); err != nil { - return 0, err - } - binary.Unmarshal(buf, ByteOrder, dst) - return int(r.Addr - addr), nil -} - -// CopyStringIn tuning parameters, defined outside that function for tests. -const ( - copyStringIncrement = 64 - copyStringMaxInitBufLen = 256 -) - -// CopyStringIn copies a NUL-terminated string of unknown length from the -// memory mapped at addr in uio and returns it as a string (not including the -// trailing NUL). If the length of the string, including the terminating NUL, -// would exceed maxlen, CopyStringIn returns the string truncated to maxlen and -// ENAMETOOLONG. -// -// Preconditions: As for IO.CopyFromUser. maxlen >= 0. -func CopyStringIn(ctx context.Context, uio IO, addr Addr, maxlen int, opts IOOpts) (string, error) { - initLen := maxlen - if initLen > copyStringMaxInitBufLen { - initLen = copyStringMaxInitBufLen - } - buf := make([]byte, initLen) - var done int - for done < maxlen { - // Read up to copyStringIncrement bytes at a time. - readlen := copyStringIncrement - if readlen > maxlen-done { - readlen = maxlen - done - } - end, ok := addr.AddLength(uint64(readlen)) - if !ok { - return stringFromImmutableBytes(buf[:done]), syserror.EFAULT - } - // Shorten the read to avoid crossing page boundaries, since faulting - // in a page unnecessarily is expensive. This also ensures that partial - // copies up to the end of application-mappable memory succeed. - if addr.RoundDown() != end.RoundDown() { - end = end.RoundDown() - readlen = int(end - addr) - } - // Ensure that our buffer is large enough to accommodate the read. - if done+readlen > len(buf) { - newBufLen := len(buf) * 2 - if newBufLen > maxlen { - newBufLen = maxlen - } - buf = append(buf, make([]byte, newBufLen-len(buf))...) - } - n, err := uio.CopyIn(ctx, addr, buf[done:done+readlen], opts) - // Look for the terminating zero byte, which may have occurred before - // hitting err. - if i := bytes.IndexByte(buf[done:done+n], byte(0)); i >= 0 { - return stringFromImmutableBytes(buf[:done+i]), nil - } - - done += n - if err != nil { - return stringFromImmutableBytes(buf[:done]), err - } - addr = end - } - return stringFromImmutableBytes(buf), syserror.ENAMETOOLONG -} - -// CopyOutVec copies bytes from src to the memory mapped at ars in uio. The -// maximum number of bytes copied is ars.NumBytes() or len(src), whichever is -// less. CopyOutVec returns the number of bytes copied; if this is less than -// the maximum, it returns a non-nil error explaining why. -// -// Preconditions: As for IO.CopyOut. -func CopyOutVec(ctx context.Context, uio IO, ars AddrRangeSeq, src []byte, opts IOOpts) (int, error) { - var done int - for !ars.IsEmpty() && done < len(src) { - ar := ars.Head() - cplen := len(src) - done - if Addr(cplen) >= ar.Length() { - cplen = int(ar.Length()) - } - n, err := uio.CopyOut(ctx, ar.Start, src[done:done+cplen], opts) - done += n - if err != nil { - return done, err - } - ars = ars.DropFirst(n) - } - return done, nil -} - -// CopyInVec copies bytes from the memory mapped at ars in uio to dst. The -// maximum number of bytes copied is ars.NumBytes() or len(dst), whichever is -// less. CopyInVec returns the number of bytes copied; if this is less than the -// maximum, it returns a non-nil error explaining why. -// -// Preconditions: As for IO.CopyIn. -func CopyInVec(ctx context.Context, uio IO, ars AddrRangeSeq, dst []byte, opts IOOpts) (int, error) { - var done int - for !ars.IsEmpty() && done < len(dst) { - ar := ars.Head() - cplen := len(dst) - done - if Addr(cplen) >= ar.Length() { - cplen = int(ar.Length()) - } - n, err := uio.CopyIn(ctx, ar.Start, dst[done:done+cplen], opts) - done += n - if err != nil { - return done, err - } - ars = ars.DropFirst(n) - } - return done, nil -} - -// ZeroOutVec writes zeroes to the memory mapped at ars in uio. The maximum -// number of bytes written is ars.NumBytes() or toZero, whichever is less. -// ZeroOutVec returns the number of bytes written; if this is less than the -// maximum, it returns a non-nil error explaining why. -// -// Preconditions: As for IO.ZeroOut. -func ZeroOutVec(ctx context.Context, uio IO, ars AddrRangeSeq, toZero int64, opts IOOpts) (int64, error) { - var done int64 - for !ars.IsEmpty() && done < toZero { - ar := ars.Head() - cplen := toZero - done - if Addr(cplen) >= ar.Length() { - cplen = int64(ar.Length()) - } - n, err := uio.ZeroOut(ctx, ar.Start, cplen, opts) - done += n - if err != nil { - return done, err - } - ars = ars.DropFirst64(n) - } - return done, nil -} - -func isASCIIWhitespace(b byte) bool { - // Compare Linux include/linux/ctype.h, lib/ctype.c. - // 9 => horizontal tab '\t' - // 10 => line feed '\n' - // 11 => vertical tab '\v' - // 12 => form feed '\c' - // 13 => carriage return '\r' - return b == ' ' || (b >= 9 && b <= 13) -} - -// CopyInt32StringsInVec copies up to len(dsts) whitespace-separated decimal -// strings from the memory mapped at ars in uio and converts them to int32 -// values in dsts. It returns the number of bytes read. -// -// CopyInt32StringsInVec shares the following properties with Linux's -// kernel/sysctl.c:proc_dointvec(write=1): -// -// - If any read value overflows the range of int32, or any invalid characters -// are encountered during the read, CopyInt32StringsInVec returns EINVAL. -// -// - If, upon reaching the end of ars, fewer than len(dsts) values have been -// read, CopyInt32StringsInVec returns no error if at least 1 value was read -// and EINVAL otherwise. -// -// - Trailing whitespace after the last successfully read value is counted in -// the number of bytes read. -// -// Unlike proc_dointvec(): -// -// - CopyInt32StringsInVec does not implicitly limit ars.NumBytes() to -// PageSize-1; callers that require this must do so explicitly. -// -// - CopyInt32StringsInVec returns EINVAL if ars.NumBytes() == 0. -// -// Preconditions: As for CopyInVec. -func CopyInt32StringsInVec(ctx context.Context, uio IO, ars AddrRangeSeq, dsts []int32, opts IOOpts) (int64, error) { - if len(dsts) == 0 { - return 0, nil - } - - buf := make([]byte, ars.NumBytes()) - n, cperr := CopyInVec(ctx, uio, ars, buf, opts) - buf = buf[:n] - - var i, j int - for ; j < len(dsts); j++ { - // Skip leading whitespace. - for i < len(buf) && isASCIIWhitespace(buf[i]) { - i++ - } - if i == len(buf) { - break - } - - // Find the end of the value to be parsed (next whitespace or end of string). - nextI := i + 1 - for nextI < len(buf) && !isASCIIWhitespace(buf[nextI]) { - nextI++ - } - - // Parse a single value. - val, err := strconv.ParseInt(string(buf[i:nextI]), 10, 32) - if err != nil { - return int64(i), syserror.EINVAL - } - dsts[j] = int32(val) - - i = nextI - } - - // Skip trailing whitespace. - for i < len(buf) && isASCIIWhitespace(buf[i]) { - i++ - } - - if cperr != nil { - return int64(i), cperr - } - if j == 0 { - return int64(i), syserror.EINVAL - } - return int64(i), nil -} - -// CopyInt32StringInVec is equivalent to CopyInt32StringsInVec, but copies at -// most one int32. -func CopyInt32StringInVec(ctx context.Context, uio IO, ars AddrRangeSeq, dst *int32, opts IOOpts) (int64, error) { - dsts := [1]int32{*dst} - n, err := CopyInt32StringsInVec(ctx, uio, ars, dsts[:], opts) - *dst = dsts[0] - return n, err -} - -// IOSequence holds arguments to IO methods. -type IOSequence struct { - IO IO - Addrs AddrRangeSeq - Opts IOOpts -} - -// NumBytes returns s.Addrs.NumBytes(). -// -// Note that NumBytes() may return 0 even if !s.Addrs.IsEmpty(), since -// s.Addrs may contain a non-zero number of zero-length AddrRanges. -// Many clients of -// IOSequence currently do something like: -// -// if ioseq.NumBytes() == 0 { -// return 0, nil -// } -// if f.availableBytes == 0 { -// return 0, syserror.ErrWouldBlock -// } -// return ioseq.CopyOutFrom(..., reader) -// -// In such cases, using s.Addrs.IsEmpty() will cause them to have the wrong -// behavior for zero-length I/O. However, using s.NumBytes() == 0 instead means -// that we will return success for zero-length I/O in cases where Linux would -// return EFAULT due to a failed access_ok() check, so in the long term we -// should move checks for ErrWouldBlock etc. into the body of -// reader.ReadToBlocks and use s.Addrs.IsEmpty() instead. -func (s IOSequence) NumBytes() int64 { - return s.Addrs.NumBytes() -} - -// DropFirst returns a copy of s with s.Addrs.DropFirst(n). -// -// Preconditions: As for AddrRangeSeq.DropFirst. -func (s IOSequence) DropFirst(n int) IOSequence { - return IOSequence{s.IO, s.Addrs.DropFirst(n), s.Opts} -} - -// DropFirst64 returns a copy of s with s.Addrs.DropFirst64(n). -// -// Preconditions: As for AddrRangeSeq.DropFirst64. -func (s IOSequence) DropFirst64(n int64) IOSequence { - return IOSequence{s.IO, s.Addrs.DropFirst64(n), s.Opts} -} - -// TakeFirst returns a copy of s with s.Addrs.TakeFirst(n). -// -// Preconditions: As for AddrRangeSeq.TakeFirst. -func (s IOSequence) TakeFirst(n int) IOSequence { - return IOSequence{s.IO, s.Addrs.TakeFirst(n), s.Opts} -} - -// TakeFirst64 returns a copy of s with s.Addrs.TakeFirst64(n). -// -// Preconditions: As for AddrRangeSeq.TakeFirst64. -func (s IOSequence) TakeFirst64(n int64) IOSequence { - return IOSequence{s.IO, s.Addrs.TakeFirst64(n), s.Opts} -} - -// CopyOut invokes CopyOutVec over s.Addrs. -// -// As with CopyOutVec, if s.NumBytes() < len(src), the copy will be truncated -// to s.NumBytes(), and a nil error will be returned. -// -// Preconditions: As for CopyOutVec. -func (s IOSequence) CopyOut(ctx context.Context, src []byte) (int, error) { - return CopyOutVec(ctx, s.IO, s.Addrs, src, s.Opts) -} - -// CopyIn invokes CopyInVec over s.Addrs. -// -// As with CopyInVec, if s.NumBytes() < len(dst), the copy will be truncated to -// s.NumBytes(), and a nil error will be returned. -// -// Preconditions: As for CopyInVec. -func (s IOSequence) CopyIn(ctx context.Context, dst []byte) (int, error) { - return CopyInVec(ctx, s.IO, s.Addrs, dst, s.Opts) -} - -// ZeroOut invokes ZeroOutVec over s.Addrs. -// -// As with ZeroOutVec, if s.NumBytes() < toZero, the write will be truncated -// to s.NumBytes(), and a nil error will be returned. -// -// Preconditions: As for ZeroOutVec. -func (s IOSequence) ZeroOut(ctx context.Context, toZero int64) (int64, error) { - return ZeroOutVec(ctx, s.IO, s.Addrs, toZero, s.Opts) -} - -// CopyOutFrom invokes s.CopyOutFrom over s.Addrs. -// -// Preconditions: As for IO.CopyOutFrom. -func (s IOSequence) CopyOutFrom(ctx context.Context, src safemem.Reader) (int64, error) { - return s.IO.CopyOutFrom(ctx, s.Addrs, src, s.Opts) -} - -// CopyInTo invokes s.CopyInTo over s.Addrs. -// -// Preconditions: As for IO.CopyInTo. -func (s IOSequence) CopyInTo(ctx context.Context, dst safemem.Writer) (int64, error) { - return s.IO.CopyInTo(ctx, s.Addrs, dst, s.Opts) -} - -// Reader returns an io.Reader that reads from s. Reads beyond the end of s -// return io.EOF. The preconditions that apply to s.CopyIn also apply to the -// returned io.Reader.Read. -func (s IOSequence) Reader(ctx context.Context) io.Reader { - return &ioSequenceReadWriter{ctx, s} -} - -// Writer returns an io.Writer that writes to s. Writes beyond the end of s -// return ErrEndOfIOSequence. The preconditions that apply to s.CopyOut also -// apply to the returned io.Writer.Write. -func (s IOSequence) Writer(ctx context.Context) io.Writer { - return &ioSequenceReadWriter{ctx, s} -} - -// ErrEndOfIOSequence is returned by IOSequence.Writer().Write() when -// attempting to write beyond the end of the IOSequence. -var ErrEndOfIOSequence = errors.New("write beyond end of IOSequence") - -type ioSequenceReadWriter struct { - ctx context.Context - s IOSequence -} - -// Read implements io.Reader.Read. -func (rw *ioSequenceReadWriter) Read(dst []byte) (int, error) { - n, err := rw.s.CopyIn(rw.ctx, dst) - rw.s = rw.s.DropFirst(n) - if err == nil && rw.s.NumBytes() == 0 { - err = io.EOF - } - return n, err -} - -// Write implements io.Writer.Write. -func (rw *ioSequenceReadWriter) Write(src []byte) (int, error) { - n, err := rw.s.CopyOut(rw.ctx, src) - rw.s = rw.s.DropFirst(n) - if err == nil && n < len(src) { - err = ErrEndOfIOSequence - } - return n, err -} diff --git a/pkg/sentry/usermem/usermem_arm64.go b/pkg/sentry/usermem/usermem_arm64.go deleted file mode 100644 index fdfc30a66..000000000 --- a/pkg/sentry/usermem/usermem_arm64.go +++ /dev/null @@ -1,53 +0,0 @@ -// Copyright 2019 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -// +build arm64 - -package usermem - -import ( - "encoding/binary" - "syscall" -) - -const ( - // PageSize is the system page size. - // arm64 support 4K/16K/64K page size, - // which can be get by syscall.Getpagesize(). - // Currently, only 4K page size is supported. - PageSize = 1 << PageShift - - // HugePageSize is the system huge page size. - HugePageSize = 1 << HugePageShift - - // PageShift is the binary log of the system page size. - PageShift = 12 - - // HugePageShift is the binary log of the system huge page size. - // Should be calculated by "PageShift + (PageShift - 3)" - // when multiple page size support is ready. - HugePageShift = 21 -) - -var ( - // ByteOrder is the native byte order (little endian). - ByteOrder = binary.LittleEndian -) - -func init() { - // Make sure the page size is 4K on arm64 platform. - if size := syscall.Getpagesize(); size != PageSize { - panic("Only 4K page size is supported on arm64!") - } -} diff --git a/pkg/sentry/usermem/usermem_test.go b/pkg/sentry/usermem/usermem_test.go deleted file mode 100644 index 299f64754..000000000 --- a/pkg/sentry/usermem/usermem_test.go +++ /dev/null @@ -1,424 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -package usermem - -import ( - "bytes" - "encoding/binary" - "fmt" - "reflect" - "strings" - "testing" - - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/safemem" - "gvisor.dev/gvisor/pkg/syserror" -) - -// newContext returns a context.Context that we can use in these tests (we -// can't use contexttest because it depends on usermem). -func newContext() context.Context { - return context.Background() -} - -func newBytesIOString(s string) *BytesIO { - return &BytesIO{[]byte(s)} -} - -func TestBytesIOCopyOutSuccess(t *testing.T) { - b := newBytesIOString("ABCDE") - n, err := b.CopyOut(newContext(), 1, []byte("foo"), IOOpts{}) - if wantN := 3; n != wantN || err != nil { - t.Errorf("CopyOut: got (%v, %v), wanted (%v, nil)", n, err, wantN) - } - if got, want := b.Bytes, []byte("AfooE"); !bytes.Equal(got, want) { - t.Errorf("Bytes: got %q, wanted %q", got, want) - } -} - -func TestBytesIOCopyOutFailure(t *testing.T) { - b := newBytesIOString("ABC") - n, err := b.CopyOut(newContext(), 1, []byte("foo"), IOOpts{}) - if wantN, wantErr := 2, syserror.EFAULT; n != wantN || err != wantErr { - t.Errorf("CopyOut: got (%v, %v), wanted (%v, %v)", n, err, wantN, wantErr) - } - if got, want := b.Bytes, []byte("Afo"); !bytes.Equal(got, want) { - t.Errorf("Bytes: got %q, wanted %q", got, want) - } -} - -func TestBytesIOCopyInSuccess(t *testing.T) { - b := newBytesIOString("AfooE") - var dst [3]byte - n, err := b.CopyIn(newContext(), 1, dst[:], IOOpts{}) - if wantN := 3; n != wantN || err != nil { - t.Errorf("CopyIn: got (%v, %v), wanted (%v, nil)", n, err, wantN) - } - if got, want := dst[:], []byte("foo"); !bytes.Equal(got, want) { - t.Errorf("dst: got %q, wanted %q", got, want) - } -} - -func TestBytesIOCopyInFailure(t *testing.T) { - b := newBytesIOString("Afo") - var dst [3]byte - n, err := b.CopyIn(newContext(), 1, dst[:], IOOpts{}) - if wantN, wantErr := 2, syserror.EFAULT; n != wantN || err != wantErr { - t.Errorf("CopyIn: got (%v, %v), wanted (%v, %v)", n, err, wantN, wantErr) - } - if got, want := dst[:], []byte("fo\x00"); !bytes.Equal(got, want) { - t.Errorf("dst: got %q, wanted %q", got, want) - } -} - -func TestBytesIOZeroOutSuccess(t *testing.T) { - b := newBytesIOString("ABCD") - n, err := b.ZeroOut(newContext(), 1, 2, IOOpts{}) - if wantN := int64(2); n != wantN || err != nil { - t.Errorf("ZeroOut: got (%v, %v), wanted (%v, nil)", n, err, wantN) - } - if got, want := b.Bytes, []byte("A\x00\x00D"); !bytes.Equal(got, want) { - t.Errorf("Bytes: got %q, wanted %q", got, want) - } -} - -func TestBytesIOZeroOutFailure(t *testing.T) { - b := newBytesIOString("ABC") - n, err := b.ZeroOut(newContext(), 1, 3, IOOpts{}) - if wantN, wantErr := int64(2), syserror.EFAULT; n != wantN || err != wantErr { - t.Errorf("ZeroOut: got (%v, %v), wanted (%v, %v)", n, err, wantN, wantErr) - } - if got, want := b.Bytes, []byte("A\x00\x00"); !bytes.Equal(got, want) { - t.Errorf("Bytes: got %q, wanted %q", got, want) - } -} - -func TestBytesIOCopyOutFromSuccess(t *testing.T) { - b := newBytesIOString("ABCDEFGH") - n, err := b.CopyOutFrom(newContext(), AddrRangeSeqFromSlice([]AddrRange{ - {Start: 4, End: 7}, - {Start: 1, End: 4}, - }), safemem.FromIOReader{bytes.NewBufferString("barfoo")}, IOOpts{}) - if wantN := int64(6); n != wantN || err != nil { - t.Errorf("CopyOutFrom: got (%v, %v), wanted (%v, nil)", n, err, wantN) - } - if got, want := b.Bytes, []byte("AfoobarH"); !bytes.Equal(got, want) { - t.Errorf("Bytes: got %q, wanted %q", got, want) - } -} - -func TestBytesIOCopyOutFromFailure(t *testing.T) { - b := newBytesIOString("ABCDE") - n, err := b.CopyOutFrom(newContext(), AddrRangeSeqFromSlice([]AddrRange{ - {Start: 1, End: 4}, - {Start: 4, End: 7}, - }), safemem.FromIOReader{bytes.NewBufferString("foobar")}, IOOpts{}) - if wantN, wantErr := int64(4), syserror.EFAULT; n != wantN || err != wantErr { - t.Errorf("CopyOutFrom: got (%v, %v), wanted (%v, %v)", n, err, wantN, wantErr) - } - if got, want := b.Bytes, []byte("Afoob"); !bytes.Equal(got, want) { - t.Errorf("Bytes: got %q, wanted %q", got, want) - } -} - -func TestBytesIOCopyInToSuccess(t *testing.T) { - b := newBytesIOString("AfoobarH") - var dst bytes.Buffer - n, err := b.CopyInTo(newContext(), AddrRangeSeqFromSlice([]AddrRange{ - {Start: 4, End: 7}, - {Start: 1, End: 4}, - }), safemem.FromIOWriter{&dst}, IOOpts{}) - if wantN := int64(6); n != wantN || err != nil { - t.Errorf("CopyInTo: got (%v, %v), wanted (%v, nil)", n, err, wantN) - } - if got, want := dst.Bytes(), []byte("barfoo"); !bytes.Equal(got, want) { - t.Errorf("dst.Bytes(): got %q, wanted %q", got, want) - } -} - -func TestBytesIOCopyInToFailure(t *testing.T) { - b := newBytesIOString("Afoob") - var dst bytes.Buffer - n, err := b.CopyInTo(newContext(), AddrRangeSeqFromSlice([]AddrRange{ - {Start: 1, End: 4}, - {Start: 4, End: 7}, - }), safemem.FromIOWriter{&dst}, IOOpts{}) - if wantN, wantErr := int64(4), syserror.EFAULT; n != wantN || err != wantErr { - t.Errorf("CopyOutFrom: got (%v, %v), wanted (%v, %v)", n, err, wantN, wantErr) - } - if got, want := dst.Bytes(), []byte("foob"); !bytes.Equal(got, want) { - t.Errorf("dst.Bytes(): got %q, wanted %q", got, want) - } -} - -type testStruct struct { - Int8 int8 - Uint8 uint8 - Int16 int16 - Uint16 uint16 - Int32 int32 - Uint32 uint32 - Int64 int64 - Uint64 uint64 -} - -func TestCopyObject(t *testing.T) { - wantObj := testStruct{1, 2, 3, 4, 5, 6, 7, 8} - wantN := binary.Size(wantObj) - b := &BytesIO{make([]byte, wantN)} - ctx := newContext() - if n, err := CopyObjectOut(ctx, b, 0, &wantObj, IOOpts{}); n != wantN || err != nil { - t.Fatalf("CopyObjectOut: got (%v, %v), wanted (%v, nil)", n, err, wantN) - } - var gotObj testStruct - if n, err := CopyObjectIn(ctx, b, 0, &gotObj, IOOpts{}); n != wantN || err != nil { - t.Errorf("CopyObjectIn: got (%v, %v), wanted (%v, nil)", n, err, wantN) - } - if gotObj != wantObj { - t.Errorf("CopyObject round trip: got %+v, wanted %+v", gotObj, wantObj) - } -} - -func TestCopyStringInShort(t *testing.T) { - // Tests for string length <= copyStringIncrement. - want := strings.Repeat("A", copyStringIncrement-2) - mem := want + "\x00" - if got, err := CopyStringIn(newContext(), newBytesIOString(mem), 0, 2*copyStringIncrement, IOOpts{}); got != want || err != nil { - t.Errorf("CopyStringIn: got (%q, %v), wanted (%q, nil)", got, err, want) - } -} - -func TestCopyStringInLong(t *testing.T) { - // Tests for copyStringIncrement < string length <= copyStringMaxInitBufLen - // (requiring multiple calls to IO.CopyIn()). - want := strings.Repeat("A", copyStringIncrement*3/4) + strings.Repeat("B", copyStringIncrement*3/4) - mem := want + "\x00" - if got, err := CopyStringIn(newContext(), newBytesIOString(mem), 0, 2*copyStringIncrement, IOOpts{}); got != want || err != nil { - t.Errorf("CopyStringIn: got (%q, %v), wanted (%q, nil)", got, err, want) - } -} - -func TestCopyStringInVeryLong(t *testing.T) { - // Tests for string length > copyStringMaxInitBufLen (requiring buffer - // reallocation). - want := strings.Repeat("A", copyStringMaxInitBufLen*3/4) + strings.Repeat("B", copyStringMaxInitBufLen*3/4) - mem := want + "\x00" - if got, err := CopyStringIn(newContext(), newBytesIOString(mem), 0, 2*copyStringMaxInitBufLen, IOOpts{}); got != want || err != nil { - t.Errorf("CopyStringIn: got (%q, %v), wanted (%q, nil)", got, err, want) - } -} - -func TestCopyStringInNoTerminatingZeroByte(t *testing.T) { - want := strings.Repeat("A", copyStringIncrement-1) - got, err := CopyStringIn(newContext(), newBytesIOString(want), 0, 2*copyStringIncrement, IOOpts{}) - if wantErr := syserror.EFAULT; got != want || err != wantErr { - t.Errorf("CopyStringIn: got (%q, %v), wanted (%q, %v)", got, err, want, wantErr) - } -} - -func TestCopyStringInTruncatedByMaxlen(t *testing.T) { - got, err := CopyStringIn(newContext(), newBytesIOString(strings.Repeat("A", 10)), 0, 5, IOOpts{}) - if want, wantErr := strings.Repeat("A", 5), syserror.ENAMETOOLONG; got != want || err != wantErr { - t.Errorf("CopyStringIn: got (%q, %v), wanted (%q, %v)", got, err, want, wantErr) - } -} - -func TestCopyInt32StringsInVec(t *testing.T) { - for _, test := range []struct { - str string - n int - initial []int32 - final []int32 - }{ - { - str: "100 200", - n: len("100 200"), - initial: []int32{1, 2}, - final: []int32{100, 200}, - }, - { - // Fewer values ok - str: "100", - n: len("100"), - initial: []int32{1, 2}, - final: []int32{100, 2}, - }, - { - // Extra values ok - str: "100 200 300", - n: len("100 200 "), - initial: []int32{1, 2}, - final: []int32{100, 200}, - }, - { - // Leading and trailing whitespace ok - str: " 100\t200\n", - n: len(" 100\t200\n"), - initial: []int32{1, 2}, - final: []int32{100, 200}, - }, - } { - t.Run(fmt.Sprintf("%q", test.str), func(t *testing.T) { - src := BytesIOSequence([]byte(test.str)) - dsts := append([]int32(nil), test.initial...) - if n, err := CopyInt32StringsInVec(newContext(), src.IO, src.Addrs, dsts, src.Opts); n != int64(test.n) || err != nil { - t.Errorf("CopyInt32StringsInVec: got (%d, %v), wanted (%d, nil)", n, err, test.n) - } - if !reflect.DeepEqual(dsts, test.final) { - t.Errorf("dsts: got %v, wanted %v", dsts, test.final) - } - }) - } -} - -func TestCopyInt32StringsInVecRequiresOneValidValue(t *testing.T) { - for _, s := range []string{"", "\n", "a123"} { - t.Run(fmt.Sprintf("%q", s), func(t *testing.T) { - src := BytesIOSequence([]byte(s)) - initial := []int32{1, 2} - dsts := append([]int32(nil), initial...) - if n, err := CopyInt32StringsInVec(newContext(), src.IO, src.Addrs, dsts, src.Opts); err != syserror.EINVAL { - t.Errorf("CopyInt32StringsInVec: got (%d, %v), wanted (_, %v)", n, err, syserror.EINVAL) - } - if !reflect.DeepEqual(dsts, initial) { - t.Errorf("dsts: got %v, wanted %v", dsts, initial) - } - }) - } -} - -func TestIOSequenceCopyOut(t *testing.T) { - buf := []byte("ABCD") - s := BytesIOSequence(buf) - - // CopyOut limited by len(src). - n, err := s.CopyOut(newContext(), []byte("fo")) - if wantN := 2; n != wantN || err != nil { - t.Errorf("CopyOut: got (%v, %v), wanted (%v, nil)", n, err, wantN) - } - if want := []byte("foCD"); !bytes.Equal(buf, want) { - t.Errorf("buf: got %q, wanted %q", buf, want) - } - s = s.DropFirst(2) - if got, want := s.NumBytes(), int64(2); got != want { - t.Errorf("NumBytes: got %v, wanted %v", got, want) - } - - // CopyOut limited by s.NumBytes(). - n, err = s.CopyOut(newContext(), []byte("obar")) - if wantN := 2; n != wantN || err != nil { - t.Errorf("CopyOut: got (%v, %v), wanted (%v, nil)", n, err, wantN) - } - if want := []byte("foob"); !bytes.Equal(buf, want) { - t.Errorf("buf: got %q, wanted %q", buf, want) - } - s = s.DropFirst(2) - if got, want := s.NumBytes(), int64(0); got != want { - t.Errorf("NumBytes: got %v, wanted %v", got, want) - } -} - -func TestIOSequenceCopyIn(t *testing.T) { - s := BytesIOSequence([]byte("foob")) - dst := []byte("ABCDEF") - - // CopyIn limited by len(dst). - n, err := s.CopyIn(newContext(), dst[:2]) - if wantN := 2; n != wantN || err != nil { - t.Errorf("CopyIn: got (%v, %v), wanted (%v, nil)", n, err, wantN) - } - if want := []byte("foCDEF"); !bytes.Equal(dst, want) { - t.Errorf("dst: got %q, wanted %q", dst, want) - } - s = s.DropFirst(2) - if got, want := s.NumBytes(), int64(2); got != want { - t.Errorf("NumBytes: got %v, wanted %v", got, want) - } - - // CopyIn limited by s.Remaining(). - n, err = s.CopyIn(newContext(), dst[2:]) - if wantN := 2; n != wantN || err != nil { - t.Errorf("CopyIn: got (%v, %v), wanted (%v, nil)", n, err, wantN) - } - if want := []byte("foobEF"); !bytes.Equal(dst, want) { - t.Errorf("dst: got %q, wanted %q", dst, want) - } - s = s.DropFirst(2) - if got, want := s.NumBytes(), int64(0); got != want { - t.Errorf("NumBytes: got %v, wanted %v", got, want) - } -} - -func TestIOSequenceZeroOut(t *testing.T) { - buf := []byte("ABCD") - s := BytesIOSequence(buf) - - // ZeroOut limited by toZero. - n, err := s.ZeroOut(newContext(), 2) - if wantN := int64(2); n != wantN || err != nil { - t.Errorf("ZeroOut: got (%v, %v), wanted (%v, nil)", n, err, wantN) - } - if want := []byte("\x00\x00CD"); !bytes.Equal(buf, want) { - t.Errorf("buf: got %q, wanted %q", buf, want) - } - s = s.DropFirst(2) - if got, want := s.NumBytes(), int64(2); got != want { - t.Errorf("NumBytes: got %v, wanted %v", got, want) - } - - // ZeroOut limited by s.NumBytes(). - n, err = s.ZeroOut(newContext(), 4) - if wantN := int64(2); n != wantN || err != nil { - t.Errorf("CopyOut: got (%v, %v), wanted (%v, nil)", n, err, wantN) - } - if want := []byte("\x00\x00\x00\x00"); !bytes.Equal(buf, want) { - t.Errorf("buf: got %q, wanted %q", buf, want) - } - s = s.DropFirst(2) - if got, want := s.NumBytes(), int64(0); got != want { - t.Errorf("NumBytes: got %v, wanted %v", got, want) - } -} - -func TestIOSequenceTakeFirst(t *testing.T) { - s := BytesIOSequence([]byte("foobar")) - if got, want := s.NumBytes(), int64(6); got != want { - t.Errorf("NumBytes: got %v, wanted %v", got, want) - } - - s = s.TakeFirst(3) - if got, want := s.NumBytes(), int64(3); got != want { - t.Errorf("NumBytes: got %v, wanted %v", got, want) - } - - // TakeFirst(n) where n > s.NumBytes() is a no-op. - s = s.TakeFirst(9) - if got, want := s.NumBytes(), int64(3); got != want { - t.Errorf("NumBytes: got %v, wanted %v", got, want) - } - - var dst [3]byte - n, err := s.CopyIn(newContext(), dst[:]) - if wantN := 3; n != wantN || err != nil { - t.Errorf("CopyIn: got (%v, %v), wanted (%v, nil)", n, err, wantN) - } - if got, want := dst[:], []byte("foo"); !bytes.Equal(got, want) { - t.Errorf("dst: got %q, wanted %q", got, want) - } - s = s.DropFirst(3) - if got, want := s.NumBytes(), int64(0); got != want { - t.Errorf("NumBytes: got %v, wanted %v", got, want) - } -} diff --git a/pkg/sentry/usermem/usermem_unsafe.go b/pkg/sentry/usermem/usermem_unsafe.go deleted file mode 100644 index 876783e78..000000000 --- a/pkg/sentry/usermem/usermem_unsafe.go +++ /dev/null @@ -1,27 +0,0 @@ -// Copyright 2019 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -package usermem - -import ( - "unsafe" -) - -// stringFromImmutableBytes is equivalent to string(bs), except that it never -// copies even if escape analysis can't prove that bs does not escape. This is -// only valid if bs is never mutated after stringFromImmutableBytes returns. -func stringFromImmutableBytes(bs []byte) string { - // Compare strings.Builder.String(). - return *(*string)(unsafe.Pointer(&bs)) -} diff --git a/pkg/sentry/usermem/usermem_x86.go b/pkg/sentry/usermem/usermem_x86.go deleted file mode 100644 index 8059b72d2..000000000 --- a/pkg/sentry/usermem/usermem_x86.go +++ /dev/null @@ -1,38 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -// +build amd64 i386 - -package usermem - -import "encoding/binary" - -const ( - // PageSize is the system page size. - PageSize = 1 << PageShift - - // HugePageSize is the system huge page size. - HugePageSize = 1 << HugePageShift - - // PageShift is the binary log of the system page size. - PageShift = 12 - - // HugePageShift is the binary log of the system huge page size. - HugePageShift = 21 -) - -var ( - // ByteOrder is the native byte order (little endian). - ByteOrder = binary.LittleEndian -) diff --git a/pkg/sentry/vfs/BUILD b/pkg/sentry/vfs/BUILD index 51acdc4e9..6b1009328 100644 --- a/pkg/sentry/vfs/BUILD +++ b/pkg/sentry/vfs/BUILD @@ -26,14 +26,14 @@ go_library( visibility = ["//pkg/sentry:internal"], deps = [ "//pkg/abi/linux", + "//pkg/context", "//pkg/fspath", "//pkg/sentry/arch", - "//pkg/sentry/context", "//pkg/sentry/kernel/auth", "//pkg/sentry/memmap", - "//pkg/sentry/usermem", "//pkg/sync", "//pkg/syserror", + "//pkg/usermem", "//pkg/waiter", ], ) @@ -48,11 +48,11 @@ go_test( library = ":vfs", deps = [ "//pkg/abi/linux", - "//pkg/sentry/context", - "//pkg/sentry/context/contexttest", + "//pkg/context", + "//pkg/sentry/contexttest", "//pkg/sentry/kernel/auth", - "//pkg/sentry/usermem", "//pkg/sync", "//pkg/syserror", + "//pkg/usermem", ], ) diff --git a/pkg/sentry/vfs/context.go b/pkg/sentry/vfs/context.go index 705194ebc..d97362b9a 100644 --- a/pkg/sentry/vfs/context.go +++ b/pkg/sentry/vfs/context.go @@ -15,7 +15,7 @@ package vfs import ( - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" ) // contextID is this package's type for context.Context.Value keys. diff --git a/pkg/sentry/vfs/device.go b/pkg/sentry/vfs/device.go index 9f9d6e783..3af2aa58d 100644 --- a/pkg/sentry/vfs/device.go +++ b/pkg/sentry/vfs/device.go @@ -17,7 +17,7 @@ package vfs import ( "fmt" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/syserror" ) diff --git a/pkg/sentry/vfs/file_description.go b/pkg/sentry/vfs/file_description.go index 51c95c2d9..225024463 100644 --- a/pkg/sentry/vfs/file_description.go +++ b/pkg/sentry/vfs/file_description.go @@ -18,12 +18,12 @@ import ( "sync/atomic" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/memmap" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/vfs/file_description_impl_util.go b/pkg/sentry/vfs/file_description_impl_util.go index c00b3c84b..fb9b87fdc 100644 --- a/pkg/sentry/vfs/file_description_impl_util.go +++ b/pkg/sentry/vfs/file_description_impl_util.go @@ -19,12 +19,12 @@ import ( "io" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/memmap" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) diff --git a/pkg/sentry/vfs/file_description_impl_util_test.go b/pkg/sentry/vfs/file_description_impl_util_test.go index 9ed58512f..1720d325d 100644 --- a/pkg/sentry/vfs/file_description_impl_util_test.go +++ b/pkg/sentry/vfs/file_description_impl_util_test.go @@ -22,11 +22,11 @@ import ( "testing" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // fileDescription is the common fd struct which a filesystem implementation diff --git a/pkg/sentry/vfs/filesystem.go b/pkg/sentry/vfs/filesystem.go index ea78f555b..a06a6caf3 100644 --- a/pkg/sentry/vfs/filesystem.go +++ b/pkg/sentry/vfs/filesystem.go @@ -18,8 +18,8 @@ import ( "sync/atomic" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fspath" - "gvisor.dev/gvisor/pkg/sentry/context" ) // A Filesystem is a tree of nodes represented by Dentries, which forms part of diff --git a/pkg/sentry/vfs/filesystem_type.go b/pkg/sentry/vfs/filesystem_type.go index 023301780..c58b70728 100644 --- a/pkg/sentry/vfs/filesystem_type.go +++ b/pkg/sentry/vfs/filesystem_type.go @@ -18,7 +18,7 @@ import ( "bytes" "fmt" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" ) diff --git a/pkg/sentry/vfs/mount.go b/pkg/sentry/vfs/mount.go index 00177b371..d39528051 100644 --- a/pkg/sentry/vfs/mount.go +++ b/pkg/sentry/vfs/mount.go @@ -19,7 +19,7 @@ import ( "sync/atomic" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/syserror" ) diff --git a/pkg/sentry/vfs/pathname.go b/pkg/sentry/vfs/pathname.go index cf80df90e..b318c681a 100644 --- a/pkg/sentry/vfs/pathname.go +++ b/pkg/sentry/vfs/pathname.go @@ -15,8 +15,8 @@ package vfs import ( + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fspath" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" ) diff --git a/pkg/sentry/vfs/testutil.go b/pkg/sentry/vfs/testutil.go index ee5c8b9e2..392c7611e 100644 --- a/pkg/sentry/vfs/testutil.go +++ b/pkg/sentry/vfs/testutil.go @@ -18,8 +18,8 @@ import ( "fmt" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fspath" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/syserror" ) diff --git a/pkg/sentry/vfs/vfs.go b/pkg/sentry/vfs/vfs.go index 1f6f56293..b2bf48853 100644 --- a/pkg/sentry/vfs/vfs.go +++ b/pkg/sentry/vfs/vfs.go @@ -31,8 +31,8 @@ import ( "fmt" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fspath" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" diff --git a/pkg/usermem/BUILD b/pkg/usermem/BUILD new file mode 100644 index 000000000..ff8b9e91a --- /dev/null +++ b/pkg/usermem/BUILD @@ -0,0 +1,55 @@ +load("//tools:defs.bzl", "go_library", "go_test") +load("//tools/go_generics:defs.bzl", "go_template_instance") + +package(licenses = ["notice"]) + +go_template_instance( + name = "addr_range", + out = "addr_range.go", + package = "usermem", + prefix = "Addr", + template = "//pkg/segment:generic_range", + types = { + "T": "Addr", + }, +) + +go_library( + name = "usermem", + srcs = [ + "access_type.go", + "addr.go", + "addr_range.go", + "addr_range_seq_unsafe.go", + "bytes_io.go", + "bytes_io_unsafe.go", + "usermem.go", + "usermem_arm64.go", + "usermem_unsafe.go", + "usermem_x86.go", + ], + visibility = ["//:sandbox"], + deps = [ + "//pkg/atomicbitops", + "//pkg/binary", + "//pkg/context", + "//pkg/log", + "//pkg/safemem", + "//pkg/syserror", + ], +) + +go_test( + name = "usermem_test", + size = "small", + srcs = [ + "addr_range_seq_test.go", + "usermem_test.go", + ], + library = ":usermem", + deps = [ + "//pkg/context", + "//pkg/safemem", + "//pkg/syserror", + ], +) diff --git a/pkg/usermem/README.md b/pkg/usermem/README.md new file mode 100644 index 000000000..f6d2137eb --- /dev/null +++ b/pkg/usermem/README.md @@ -0,0 +1,31 @@ +This package defines primitives for sentry access to application memory. + +Major types: + +- The `IO` interface represents a virtual address space and provides I/O + methods on that address space. `IO` is the lowest-level primitive. The + primary implementation of the `IO` interface is `mm.MemoryManager`. + +- `IOSequence` represents a collection of individually-contiguous address + ranges in a `IO` that is operated on sequentially, analogous to Linux's + `struct iov_iter`. + +Major usage patterns: + +- Access to a task's virtual memory, subject to the application's memory + protections and while running on that task's goroutine, from a context that + is at or above the level of the `kernel` package (e.g. most syscall + implementations in `syscalls/linux`); use the `kernel.Task.Copy*` wrappers + defined in `kernel/task_usermem.go`. + +- Access to a task's virtual memory, from a context that is at or above the + level of the `kernel` package, but where any of the above constraints does + not hold (e.g. `PTRACE_POKEDATA`, which ignores application memory + protections); obtain the task's `mm.MemoryManager` by calling + `kernel.Task.MemoryManager`, and call its `IO` methods directly. + +- Access to a task's virtual memory, from a context that is below the level of + the `kernel` package (e.g. filesystem I/O); clients must pass I/O arguments + from higher layers, usually in the form of an `IOSequence`. The + `kernel.Task.SingleIOSequence` and `kernel.Task.IovecsIOSequence` functions + in `kernel/task_usermem.go` are convenience functions for doing so. diff --git a/pkg/usermem/access_type.go b/pkg/usermem/access_type.go new file mode 100644 index 000000000..9c1742a59 --- /dev/null +++ b/pkg/usermem/access_type.go @@ -0,0 +1,128 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package usermem + +import ( + "syscall" +) + +// AccessType specifies memory access types. This is used for +// setting mapping permissions, as well as communicating faults. +// +// +stateify savable +type AccessType struct { + // Read is read access. + Read bool + + // Write is write access. + Write bool + + // Execute is executable access. + Execute bool +} + +// String returns a pretty representation of access. This looks like the +// familiar r-x, rw-, etc. and can be relied on as such. +func (a AccessType) String() string { + bits := [3]byte{'-', '-', '-'} + if a.Read { + bits[0] = 'r' + } + if a.Write { + bits[1] = 'w' + } + if a.Execute { + bits[2] = 'x' + } + return string(bits[:]) +} + +// Any returns true iff at least one of Read, Write or Execute is true. +func (a AccessType) Any() bool { + return a.Read || a.Write || a.Execute +} + +// Prot returns the system prot (syscall.PROT_READ, etc.) for this access. +func (a AccessType) Prot() int { + var prot int + if a.Read { + prot |= syscall.PROT_READ + } + if a.Write { + prot |= syscall.PROT_WRITE + } + if a.Execute { + prot |= syscall.PROT_EXEC + } + return prot +} + +// SupersetOf returns true iff the access types in a are a superset of the +// access types in other. +func (a AccessType) SupersetOf(other AccessType) bool { + if !a.Read && other.Read { + return false + } + if !a.Write && other.Write { + return false + } + if !a.Execute && other.Execute { + return false + } + return true +} + +// Intersect returns the access types set in both a and other. +func (a AccessType) Intersect(other AccessType) AccessType { + return AccessType{ + Read: a.Read && other.Read, + Write: a.Write && other.Write, + Execute: a.Execute && other.Execute, + } +} + +// Union returns the access types set in either a or other. +func (a AccessType) Union(other AccessType) AccessType { + return AccessType{ + Read: a.Read || other.Read, + Write: a.Write || other.Write, + Execute: a.Execute || other.Execute, + } +} + +// Effective returns the set of effective access types allowed by a, even if +// some types are not explicitly allowed. +func (a AccessType) Effective() AccessType { + // In Linux, Write and Execute access generally imply Read access. See + // mm/mmap.c:protection_map. + // + // The notable exception is get_user_pages, which only checks against + // the original vma flags. That said, most user memory accesses do not + // use GUP. + if a.Write || a.Execute { + a.Read = true + } + return a +} + +// Convenient access types. +var ( + NoAccess = AccessType{} + Read = AccessType{Read: true} + Write = AccessType{Write: true} + Execute = AccessType{Execute: true} + ReadWrite = AccessType{Read: true, Write: true} + AnyAccess = AccessType{Read: true, Write: true, Execute: true} +) diff --git a/pkg/usermem/addr.go b/pkg/usermem/addr.go new file mode 100644 index 000000000..e79210804 --- /dev/null +++ b/pkg/usermem/addr.go @@ -0,0 +1,108 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package usermem + +import ( + "fmt" +) + +// Addr represents a generic virtual address. +// +// +stateify savable +type Addr uintptr + +// AddLength adds the given length to start and returns the result. ok is true +// iff adding the length did not overflow the range of Addr. +// +// Note: This function is usually used to get the end of an address range +// defined by its start address and length. Since the resulting end is +// exclusive, end == 0 is technically valid, and corresponds to a range that +// extends to the end of the address space, but ok will be false. This isn't +// expected to ever come up in practice. +func (v Addr) AddLength(length uint64) (end Addr, ok bool) { + end = v + Addr(length) + // The second half of the following check is needed in case uintptr is + // smaller than 64 bits. + ok = end >= v && length <= uint64(^Addr(0)) + return +} + +// RoundDown returns the address rounded down to the nearest page boundary. +func (v Addr) RoundDown() Addr { + return v & ^Addr(PageSize-1) +} + +// RoundUp returns the address rounded up to the nearest page boundary. ok is +// true iff rounding up did not wrap around. +func (v Addr) RoundUp() (addr Addr, ok bool) { + addr = Addr(v + PageSize - 1).RoundDown() + ok = addr >= v + return +} + +// MustRoundUp is equivalent to RoundUp, but panics if rounding up wraps +// around. +func (v Addr) MustRoundUp() Addr { + addr, ok := v.RoundUp() + if !ok { + panic(fmt.Sprintf("usermem.Addr(%d).RoundUp() wraps", v)) + } + return addr +} + +// HugeRoundDown returns the address rounded down to the nearest huge page +// boundary. +func (v Addr) HugeRoundDown() Addr { + return v & ^Addr(HugePageSize-1) +} + +// HugeRoundUp returns the address rounded up to the nearest huge page boundary. +// ok is true iff rounding up did not wrap around. +func (v Addr) HugeRoundUp() (addr Addr, ok bool) { + addr = Addr(v + HugePageSize - 1).HugeRoundDown() + ok = addr >= v + return +} + +// PageOffset returns the offset of v into the current page. +func (v Addr) PageOffset() uint64 { + return uint64(v & Addr(PageSize-1)) +} + +// IsPageAligned returns true if v.PageOffset() == 0. +func (v Addr) IsPageAligned() bool { + return v.PageOffset() == 0 +} + +// AddrRange is a range of Addrs. +// +// type AddrRange + +// ToRange returns [v, v+length). +func (v Addr) ToRange(length uint64) (AddrRange, bool) { + end, ok := v.AddLength(length) + return AddrRange{v, end}, ok +} + +// IsPageAligned returns true if ar.Start.IsPageAligned() and +// ar.End.IsPageAligned(). +func (ar AddrRange) IsPageAligned() bool { + return ar.Start.IsPageAligned() && ar.End.IsPageAligned() +} + +// String implements fmt.Stringer.String. +func (ar AddrRange) String() string { + return fmt.Sprintf("[%#x, %#x)", ar.Start, ar.End) +} diff --git a/pkg/usermem/addr_range_seq_test.go b/pkg/usermem/addr_range_seq_test.go new file mode 100644 index 000000000..82f735026 --- /dev/null +++ b/pkg/usermem/addr_range_seq_test.go @@ -0,0 +1,197 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package usermem + +import ( + "testing" +) + +var addrRangeSeqTests = []struct { + desc string + ranges []AddrRange +}{ + { + desc: "Empty sequence", + }, + { + desc: "Single empty AddrRange", + ranges: []AddrRange{ + {0x10, 0x10}, + }, + }, + { + desc: "Single non-empty AddrRange of length 1", + ranges: []AddrRange{ + {0x10, 0x11}, + }, + }, + { + desc: "Single non-empty AddrRange of length 2", + ranges: []AddrRange{ + {0x10, 0x12}, + }, + }, + { + desc: "Multiple non-empty AddrRanges", + ranges: []AddrRange{ + {0x10, 0x11}, + {0x20, 0x22}, + }, + }, + { + desc: "Multiple AddrRanges including empty AddrRanges", + ranges: []AddrRange{ + {0x10, 0x10}, + {0x20, 0x20}, + {0x30, 0x33}, + {0x40, 0x44}, + {0x50, 0x50}, + {0x60, 0x60}, + {0x70, 0x77}, + {0x80, 0x88}, + {0x90, 0x90}, + {0xa0, 0xa0}, + }, + }, +} + +func testAddrRangeSeqEqualityWithTailIteration(t *testing.T, ars AddrRangeSeq, wantRanges []AddrRange) { + var wantLen int64 + for _, ar := range wantRanges { + wantLen += int64(ar.Length()) + } + + var i int + for !ars.IsEmpty() { + if gotLen := ars.NumBytes(); gotLen != wantLen { + t.Errorf("Iteration %d: %v.NumBytes(): got %d, wanted %d", i, ars, gotLen, wantLen) + } + if gotN, wantN := ars.NumRanges(), len(wantRanges)-i; gotN != wantN { + t.Errorf("Iteration %d: %v.NumRanges(): got %d, wanted %d", i, ars, gotN, wantN) + } + got := ars.Head() + if i >= len(wantRanges) { + t.Errorf("Iteration %d: %v.Head(): got %s, wanted ", i, ars, got) + } else if want := wantRanges[i]; got != want { + t.Errorf("Iteration %d: %v.Head(): got %s, wanted %s", i, ars, got, want) + } + ars = ars.Tail() + wantLen -= int64(got.Length()) + i++ + } + if gotLen := ars.NumBytes(); gotLen != 0 || wantLen != 0 { + t.Errorf("Iteration %d: %v.NumBytes(): got %d, wanted %d (which should be 0)", i, ars, gotLen, wantLen) + } + if gotN := ars.NumRanges(); gotN != 0 { + t.Errorf("Iteration %d: %v.NumRanges(): got %d, wanted 0", i, ars, gotN) + } +} + +func TestAddrRangeSeqTailIteration(t *testing.T) { + for _, test := range addrRangeSeqTests { + t.Run(test.desc, func(t *testing.T) { + testAddrRangeSeqEqualityWithTailIteration(t, AddrRangeSeqFromSlice(test.ranges), test.ranges) + }) + } +} + +func TestAddrRangeSeqDropFirstEmpty(t *testing.T) { + var ars AddrRangeSeq + if got, want := ars.DropFirst(1), ars; got != want { + t.Errorf("%v.DropFirst(1): got %v, wanted %v", ars, got, want) + } +} + +func TestAddrRangeSeqDropSingleByteIteration(t *testing.T) { + // Tests AddrRangeSeq iteration using Head/DropFirst, simulating + // I/O-per-AddrRange. + for _, test := range addrRangeSeqTests { + t.Run(test.desc, func(t *testing.T) { + // Figure out what AddrRanges we expect to see. + var wantLen int64 + var wantRanges []AddrRange + for _, ar := range test.ranges { + wantLen += int64(ar.Length()) + wantRanges = append(wantRanges, ar) + if ar.Length() == 0 { + // We "do" 0 bytes of I/O and then call DropFirst(0), + // advancing to the next AddrRange. + continue + } + // Otherwise we "do" 1 byte of I/O and then call DropFirst(1), + // advancing the AddrRange by 1 byte, or to the next AddrRange + // if this one is exhausted. + for ar.Start++; ar.Length() != 0; ar.Start++ { + wantRanges = append(wantRanges, ar) + } + } + t.Logf("Expected AddrRanges: %s (%d bytes)", wantRanges, wantLen) + + ars := AddrRangeSeqFromSlice(test.ranges) + var i int + for !ars.IsEmpty() { + if gotLen := ars.NumBytes(); gotLen != wantLen { + t.Errorf("Iteration %d: %v.NumBytes(): got %d, wanted %d", i, ars, gotLen, wantLen) + } + got := ars.Head() + if i >= len(wantRanges) { + t.Errorf("Iteration %d: %v.Head(): got %s, wanted ", i, ars, got) + } else if want := wantRanges[i]; got != want { + t.Errorf("Iteration %d: %v.Head(): got %s, wanted %s", i, ars, got, want) + } + if got.Length() == 0 { + ars = ars.DropFirst(0) + } else { + ars = ars.DropFirst(1) + wantLen-- + } + i++ + } + if gotLen := ars.NumBytes(); gotLen != 0 || wantLen != 0 { + t.Errorf("Iteration %d: %v.NumBytes(): got %d, wanted %d (which should be 0)", i, ars, gotLen, wantLen) + } + }) + } +} + +func TestAddrRangeSeqTakeFirstEmpty(t *testing.T) { + var ars AddrRangeSeq + if got, want := ars.TakeFirst(1), ars; got != want { + t.Errorf("%v.TakeFirst(1): got %v, wanted %v", ars, got, want) + } +} + +func TestAddrRangeSeqTakeFirst(t *testing.T) { + ranges := []AddrRange{ + {0x10, 0x11}, + {0x20, 0x22}, + {0x30, 0x30}, + {0x40, 0x44}, + {0x50, 0x55}, + {0x60, 0x60}, + {0x70, 0x77}, + } + ars := AddrRangeSeqFromSlice(ranges).TakeFirst(5) + want := []AddrRange{ + {0x10, 0x11}, // +1 byte (total 1 byte), not truncated + {0x20, 0x22}, // +2 bytes (total 3 bytes), not truncated + {0x30, 0x30}, // +0 bytes (total 3 bytes), no change + {0x40, 0x42}, // +2 bytes (total 5 bytes), partially truncated + {0x50, 0x50}, // +0 bytes (total 5 bytes), fully truncated + {0x60, 0x60}, // +0 bytes (total 5 bytes), "fully truncated" (no change) + {0x70, 0x70}, // +0 bytes (total 5 bytes), fully truncated + } + testAddrRangeSeqEqualityWithTailIteration(t, ars, want) +} diff --git a/pkg/usermem/addr_range_seq_unsafe.go b/pkg/usermem/addr_range_seq_unsafe.go new file mode 100644 index 000000000..c09337c15 --- /dev/null +++ b/pkg/usermem/addr_range_seq_unsafe.go @@ -0,0 +1,277 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package usermem + +import ( + "bytes" + "fmt" + "reflect" + "unsafe" +) + +// An AddrRangeSeq represents a sequence of AddrRanges. +// +// AddrRangeSeqs are immutable and may be copied by value. The zero value of +// AddrRangeSeq represents an empty sequence. +// +// An AddrRangeSeq may contain AddrRanges with a length of 0. This is necessary +// since zero-length AddrRanges are significant to MM bounds checks. +type AddrRangeSeq struct { + // If length is 0, then the AddrRangeSeq represents no AddrRanges. + // Invariants: data == 0; offset == 0; limit == 0. + // + // If length is 1, then the AddrRangeSeq represents the single + // AddrRange{offset, offset+limit}. Invariants: data == 0. + // + // Otherwise, length >= 2, and the AddrRangeSeq represents the `length` + // AddrRanges in the array of AddrRanges starting at address `data`, + // starting at `offset` bytes into the first AddrRange and limited to the + // following `limit` bytes. (AddrRanges after `limit` are still iterated, + // but are truncated to a length of 0.) Invariants: data != 0; offset <= + // data[0].Length(); limit > 0; offset+limit <= the combined length of all + // AddrRanges in the array. + data unsafe.Pointer + length int + offset Addr + limit Addr +} + +// AddrRangeSeqOf returns an AddrRangeSeq representing the single AddrRange ar. +func AddrRangeSeqOf(ar AddrRange) AddrRangeSeq { + return AddrRangeSeq{ + length: 1, + offset: ar.Start, + limit: ar.Length(), + } +} + +// AddrRangeSeqFromSlice returns an AddrRangeSeq representing all AddrRanges in +// slice. +// +// Whether the returned AddrRangeSeq shares memory with slice is unspecified; +// clients should avoid mutating slices passed to AddrRangeSeqFromSlice. +// +// Preconditions: The combined length of all AddrRanges in slice <= +// math.MaxInt64. +func AddrRangeSeqFromSlice(slice []AddrRange) AddrRangeSeq { + var limit int64 + for _, ar := range slice { + len64 := int64(ar.Length()) + if len64 < 0 { + panic(fmt.Sprintf("Length of AddrRange %v overflows int64", ar)) + } + sum := limit + len64 + if sum < limit { + panic(fmt.Sprintf("Total length of AddrRanges %v overflows int64", slice)) + } + limit = sum + } + return addrRangeSeqFromSliceLimited(slice, limit) +} + +// Preconditions: The combined length of all AddrRanges in slice <= limit. +// limit >= 0. If len(slice) != 0, then limit > 0. +func addrRangeSeqFromSliceLimited(slice []AddrRange, limit int64) AddrRangeSeq { + switch len(slice) { + case 0: + return AddrRangeSeq{} + case 1: + return AddrRangeSeq{ + length: 1, + offset: slice[0].Start, + limit: Addr(limit), + } + default: + return AddrRangeSeq{ + data: unsafe.Pointer(&slice[0]), + length: len(slice), + limit: Addr(limit), + } + } +} + +// IsEmpty returns true if ars.NumRanges() == 0. +// +// Note that since AddrRangeSeq may contain AddrRanges with a length of zero, +// an AddrRange representing 0 bytes (AddrRangeSeq.NumBytes() == 0) is not +// necessarily empty. +func (ars AddrRangeSeq) IsEmpty() bool { + return ars.length == 0 +} + +// NumRanges returns the number of AddrRanges in ars. +func (ars AddrRangeSeq) NumRanges() int { + return ars.length +} + +// NumBytes returns the number of bytes represented by ars. +func (ars AddrRangeSeq) NumBytes() int64 { + return int64(ars.limit) +} + +// Head returns the first AddrRange in ars. +// +// Preconditions: !ars.IsEmpty(). +func (ars AddrRangeSeq) Head() AddrRange { + if ars.length == 0 { + panic("empty AddrRangeSeq") + } + if ars.length == 1 { + return AddrRange{ars.offset, ars.offset + ars.limit} + } + ar := *(*AddrRange)(ars.data) + ar.Start += ars.offset + if ar.Length() > ars.limit { + ar.End = ar.Start + ars.limit + } + return ar +} + +// Tail returns an AddrRangeSeq consisting of all AddrRanges in ars after the +// first. +// +// Preconditions: !ars.IsEmpty(). +func (ars AddrRangeSeq) Tail() AddrRangeSeq { + if ars.length == 0 { + panic("empty AddrRangeSeq") + } + if ars.length == 1 { + return AddrRangeSeq{} + } + return ars.externalTail() +} + +// Preconditions: ars.length >= 2. +func (ars AddrRangeSeq) externalTail() AddrRangeSeq { + headLen := (*AddrRange)(ars.data).Length() - ars.offset + var tailLimit int64 + if ars.limit > headLen { + tailLimit = int64(ars.limit - headLen) + } + var extSlice []AddrRange + extSliceHdr := (*reflect.SliceHeader)(unsafe.Pointer(&extSlice)) + extSliceHdr.Data = uintptr(ars.data) + extSliceHdr.Len = ars.length + extSliceHdr.Cap = ars.length + return addrRangeSeqFromSliceLimited(extSlice[1:], tailLimit) +} + +// DropFirst returns an AddrRangeSeq equivalent to ars, but with the first n +// bytes omitted. If n > ars.NumBytes(), DropFirst returns an empty +// AddrRangeSeq. +// +// If !ars.IsEmpty() and ars.Head().Length() == 0, DropFirst will always omit +// at least ars.Head(), even if n == 0. This guarantees that the basic pattern +// of: +// +// for !ars.IsEmpty() { +// n, err = doIOWith(ars.Head()) +// if err != nil { +// return err +// } +// ars = ars.DropFirst(n) +// } +// +// works even in the presence of zero-length AddrRanges. +// +// Preconditions: n >= 0. +func (ars AddrRangeSeq) DropFirst(n int) AddrRangeSeq { + if n < 0 { + panic(fmt.Sprintf("invalid n: %d", n)) + } + return ars.DropFirst64(int64(n)) +} + +// DropFirst64 is equivalent to DropFirst but takes an int64. +func (ars AddrRangeSeq) DropFirst64(n int64) AddrRangeSeq { + if n < 0 { + panic(fmt.Sprintf("invalid n: %d", n)) + } + if Addr(n) > ars.limit { + return AddrRangeSeq{} + } + // Handle initial empty AddrRange. + switch ars.length { + case 0: + return AddrRangeSeq{} + case 1: + if ars.limit == 0 { + return AddrRangeSeq{} + } + default: + if rawHeadLen := (*AddrRange)(ars.data).Length(); ars.offset == rawHeadLen { + ars = ars.externalTail() + } + } + for n != 0 { + // Calling ars.Head() here is surprisingly expensive, so inline getting + // the head's length. + var headLen Addr + if ars.length == 1 { + headLen = ars.limit + } else { + headLen = (*AddrRange)(ars.data).Length() - ars.offset + } + if Addr(n) < headLen { + // Dropping ends partway through the head AddrRange. + ars.offset += Addr(n) + ars.limit -= Addr(n) + return ars + } + n -= int64(headLen) + ars = ars.Tail() + } + return ars +} + +// TakeFirst returns an AddrRangeSeq equivalent to ars, but iterating at most n +// bytes. TakeFirst never removes AddrRanges from ars; AddrRanges beyond the +// first n bytes are reduced to a length of zero, but will still be iterated. +// +// Preconditions: n >= 0. +func (ars AddrRangeSeq) TakeFirst(n int) AddrRangeSeq { + if n < 0 { + panic(fmt.Sprintf("invalid n: %d", n)) + } + return ars.TakeFirst64(int64(n)) +} + +// TakeFirst64 is equivalent to TakeFirst but takes an int64. +func (ars AddrRangeSeq) TakeFirst64(n int64) AddrRangeSeq { + if n < 0 { + panic(fmt.Sprintf("invalid n: %d", n)) + } + if ars.limit > Addr(n) { + ars.limit = Addr(n) + } + return ars +} + +// String implements fmt.Stringer.String. +func (ars AddrRangeSeq) String() string { + // This is deliberately chosen to be the same as fmt's automatic stringer + // for []AddrRange. + var buf bytes.Buffer + buf.WriteByte('[') + var sep string + for !ars.IsEmpty() { + buf.WriteString(sep) + sep = " " + buf.WriteString(ars.Head().String()) + ars = ars.Tail() + } + buf.WriteByte(']') + return buf.String() +} diff --git a/pkg/usermem/bytes_io.go b/pkg/usermem/bytes_io.go new file mode 100644 index 000000000..e177d30eb --- /dev/null +++ b/pkg/usermem/bytes_io.go @@ -0,0 +1,141 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package usermem + +import ( + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/safemem" + "gvisor.dev/gvisor/pkg/syserror" +) + +const maxInt = int(^uint(0) >> 1) + +// BytesIO implements IO using a byte slice. Addresses are interpreted as +// offsets into the slice. Reads and writes beyond the end of the slice return +// EFAULT. +type BytesIO struct { + Bytes []byte +} + +// CopyOut implements IO.CopyOut. +func (b *BytesIO) CopyOut(ctx context.Context, addr Addr, src []byte, opts IOOpts) (int, error) { + rngN, rngErr := b.rangeCheck(addr, len(src)) + if rngN == 0 { + return 0, rngErr + } + return copy(b.Bytes[int(addr):], src[:rngN]), rngErr +} + +// CopyIn implements IO.CopyIn. +func (b *BytesIO) CopyIn(ctx context.Context, addr Addr, dst []byte, opts IOOpts) (int, error) { + rngN, rngErr := b.rangeCheck(addr, len(dst)) + if rngN == 0 { + return 0, rngErr + } + return copy(dst[:rngN], b.Bytes[int(addr):]), rngErr +} + +// ZeroOut implements IO.ZeroOut. +func (b *BytesIO) ZeroOut(ctx context.Context, addr Addr, toZero int64, opts IOOpts) (int64, error) { + if toZero > int64(maxInt) { + return 0, syserror.EINVAL + } + rngN, rngErr := b.rangeCheck(addr, int(toZero)) + if rngN == 0 { + return 0, rngErr + } + zeroSlice := b.Bytes[int(addr) : int(addr)+rngN] + for i := range zeroSlice { + zeroSlice[i] = 0 + } + return int64(rngN), rngErr +} + +// CopyOutFrom implements IO.CopyOutFrom. +func (b *BytesIO) CopyOutFrom(ctx context.Context, ars AddrRangeSeq, src safemem.Reader, opts IOOpts) (int64, error) { + dsts, rngErr := b.blocksFromAddrRanges(ars) + n, err := src.ReadToBlocks(dsts) + if err != nil { + return int64(n), err + } + return int64(n), rngErr +} + +// CopyInTo implements IO.CopyInTo. +func (b *BytesIO) CopyInTo(ctx context.Context, ars AddrRangeSeq, dst safemem.Writer, opts IOOpts) (int64, error) { + srcs, rngErr := b.blocksFromAddrRanges(ars) + n, err := dst.WriteFromBlocks(srcs) + if err != nil { + return int64(n), err + } + return int64(n), rngErr +} + +func (b *BytesIO) rangeCheck(addr Addr, length int) (int, error) { + if length == 0 { + return 0, nil + } + if length < 0 { + return 0, syserror.EINVAL + } + max := Addr(len(b.Bytes)) + if addr >= max { + return 0, syserror.EFAULT + } + end, ok := addr.AddLength(uint64(length)) + if !ok || end > max { + return int(max - addr), syserror.EFAULT + } + return length, nil +} + +func (b *BytesIO) blocksFromAddrRanges(ars AddrRangeSeq) (safemem.BlockSeq, error) { + switch ars.NumRanges() { + case 0: + return safemem.BlockSeq{}, nil + case 1: + block, err := b.blockFromAddrRange(ars.Head()) + return safemem.BlockSeqOf(block), err + default: + blocks := make([]safemem.Block, 0, ars.NumRanges()) + for !ars.IsEmpty() { + block, err := b.blockFromAddrRange(ars.Head()) + if block.Len() != 0 { + blocks = append(blocks, block) + } + if err != nil { + return safemem.BlockSeqFromSlice(blocks), err + } + ars = ars.Tail() + } + return safemem.BlockSeqFromSlice(blocks), nil + } +} + +func (b *BytesIO) blockFromAddrRange(ar AddrRange) (safemem.Block, error) { + n, err := b.rangeCheck(ar.Start, int(ar.Length())) + if n == 0 { + return safemem.Block{}, err + } + return safemem.BlockFromSafeSlice(b.Bytes[int(ar.Start) : int(ar.Start)+n]), err +} + +// BytesIOSequence returns an IOSequence representing the given byte slice. +func BytesIOSequence(buf []byte) IOSequence { + return IOSequence{ + IO: &BytesIO{buf}, + Addrs: AddrRangeSeqOf(AddrRange{0, Addr(len(buf))}), + } +} diff --git a/pkg/usermem/bytes_io_unsafe.go b/pkg/usermem/bytes_io_unsafe.go new file mode 100644 index 000000000..20de5037d --- /dev/null +++ b/pkg/usermem/bytes_io_unsafe.go @@ -0,0 +1,47 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package usermem + +import ( + "sync/atomic" + "unsafe" + + "gvisor.dev/gvisor/pkg/atomicbitops" + "gvisor.dev/gvisor/pkg/context" +) + +// SwapUint32 implements IO.SwapUint32. +func (b *BytesIO) SwapUint32(ctx context.Context, addr Addr, new uint32, opts IOOpts) (uint32, error) { + if _, rngErr := b.rangeCheck(addr, 4); rngErr != nil { + return 0, rngErr + } + return atomic.SwapUint32((*uint32)(unsafe.Pointer(&b.Bytes[int(addr)])), new), nil +} + +// CompareAndSwapUint32 implements IO.CompareAndSwapUint32. +func (b *BytesIO) CompareAndSwapUint32(ctx context.Context, addr Addr, old, new uint32, opts IOOpts) (uint32, error) { + if _, rngErr := b.rangeCheck(addr, 4); rngErr != nil { + return 0, rngErr + } + return atomicbitops.CompareAndSwapUint32((*uint32)(unsafe.Pointer(&b.Bytes[int(addr)])), old, new), nil +} + +// LoadUint32 implements IO.LoadUint32. +func (b *BytesIO) LoadUint32(ctx context.Context, addr Addr, opts IOOpts) (uint32, error) { + if _, err := b.rangeCheck(addr, 4); err != nil { + return 0, err + } + return atomic.LoadUint32((*uint32)(unsafe.Pointer(&b.Bytes[int(addr)]))), nil +} diff --git a/pkg/usermem/usermem.go b/pkg/usermem/usermem.go new file mode 100644 index 000000000..71fd4e155 --- /dev/null +++ b/pkg/usermem/usermem.go @@ -0,0 +1,597 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// Package usermem governs access to user memory. +package usermem + +import ( + "bytes" + "errors" + "io" + "strconv" + + "gvisor.dev/gvisor/pkg/binary" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/safemem" + "gvisor.dev/gvisor/pkg/syserror" +) + +// IO provides access to the contents of a virtual memory space. +// +// FIXME(b/38173783): Implementations of IO cannot expect ctx to contain any +// meaningful data. +type IO interface { + // CopyOut copies len(src) bytes from src to the memory mapped at addr. It + // returns the number of bytes copied. If the number of bytes copied is < + // len(src), it returns a non-nil error explaining why. + // + // Preconditions: The caller must not hold mm.MemoryManager.mappingMu or + // any following locks in the lock order. + // + // Postconditions: CopyOut does not retain src. + CopyOut(ctx context.Context, addr Addr, src []byte, opts IOOpts) (int, error) + + // CopyIn copies len(dst) bytes from the memory mapped at addr to dst. + // It returns the number of bytes copied. If the number of bytes copied is + // < len(dst), it returns a non-nil error explaining why. + // + // Preconditions: The caller must not hold mm.MemoryManager.mappingMu or + // any following locks in the lock order. + // + // Postconditions: CopyIn does not retain dst. + CopyIn(ctx context.Context, addr Addr, dst []byte, opts IOOpts) (int, error) + + // ZeroOut sets toZero bytes to 0, starting at addr. It returns the number + // of bytes zeroed. If the number of bytes zeroed is < toZero, it returns a + // non-nil error explaining why. + // + // Preconditions: The caller must not hold mm.MemoryManager.mappingMu or + // any following locks in the lock order. toZero >= 0. + ZeroOut(ctx context.Context, addr Addr, toZero int64, opts IOOpts) (int64, error) + + // CopyOutFrom copies ars.NumBytes() bytes from src to the memory mapped at + // ars. It returns the number of bytes copied, which may be less than the + // number of bytes read from src if copying fails. CopyOutFrom may return a + // partial copy without an error iff src.ReadToBlocks returns a partial + // read without an error. + // + // CopyOutFrom calls src.ReadToBlocks at most once. + // + // Preconditions: The caller must not hold mm.MemoryManager.mappingMu or + // any following locks in the lock order. src.ReadToBlocks must not block + // on mm.MemoryManager.activeMu or any preceding locks in the lock order. + CopyOutFrom(ctx context.Context, ars AddrRangeSeq, src safemem.Reader, opts IOOpts) (int64, error) + + // CopyInTo copies ars.NumBytes() bytes from the memory mapped at ars to + // dst. It returns the number of bytes copied. CopyInTo may return a + // partial copy without an error iff dst.WriteFromBlocks returns a partial + // write without an error. + // + // CopyInTo calls dst.WriteFromBlocks at most once. + // + // Preconditions: The caller must not hold mm.MemoryManager.mappingMu or + // any following locks in the lock order. dst.WriteFromBlocks must not + // block on mm.MemoryManager.activeMu or any preceding locks in the lock + // order. + CopyInTo(ctx context.Context, ars AddrRangeSeq, dst safemem.Writer, opts IOOpts) (int64, error) + + // TODO(jamieliu): The requirement that CopyOutFrom/CopyInTo call src/dst + // at most once, which is unnecessary in most cases, forces implementations + // to gather safemem.Blocks into a single slice to pass to src/dst. Add + // CopyOutFromIter/CopyInToIter, which relaxes this restriction, to avoid + // this allocation. + + // SwapUint32 atomically sets the uint32 value at addr to new and + // returns the previous value. + // + // Preconditions: The caller must not hold mm.MemoryManager.mappingMu or + // any following locks in the lock order. addr must be aligned to a 4-byte + // boundary. + SwapUint32(ctx context.Context, addr Addr, new uint32, opts IOOpts) (uint32, error) + + // CompareAndSwapUint32 atomically compares the uint32 value at addr to + // old; if they are equal, the value in memory is replaced by new. In + // either case, the previous value stored in memory is returned. + // + // Preconditions: The caller must not hold mm.MemoryManager.mappingMu or + // any following locks in the lock order. addr must be aligned to a 4-byte + // boundary. + CompareAndSwapUint32(ctx context.Context, addr Addr, old, new uint32, opts IOOpts) (uint32, error) + + // LoadUint32 atomically loads the uint32 value at addr and returns it. + // + // Preconditions: The caller must not hold mm.MemoryManager.mappingMu or + // any following locks in the lock order. addr must be aligned to a 4-byte + // boundary. + LoadUint32(ctx context.Context, addr Addr, opts IOOpts) (uint32, error) +} + +// IOOpts contains options applicable to all IO methods. +type IOOpts struct { + // If IgnorePermissions is true, application-defined memory protections set + // by mmap(2) or mprotect(2) will be ignored. (Memory protections required + // by the target of the mapping are never ignored.) + IgnorePermissions bool + + // If AddressSpaceActive is true, the IO implementation may assume that it + // has an active AddressSpace and can therefore use AddressSpace copying + // without performing activation. See mm/io.go for details. + AddressSpaceActive bool +} + +// IOReadWriter is an io.ReadWriter that reads from / writes to addresses +// starting at addr in IO. The preconditions that apply to IO.CopyIn and +// IO.CopyOut also apply to IOReadWriter.Read and IOReadWriter.Write +// respectively. +type IOReadWriter struct { + Ctx context.Context + IO IO + Addr Addr + Opts IOOpts +} + +// Read implements io.Reader.Read. +// +// Note that an address space does not have an "end of file", so Read can only +// return io.EOF if IO.CopyIn returns io.EOF. Attempts to read unmapped or +// unreadable memory, or beyond the end of the address space, should return +// EFAULT. +func (rw *IOReadWriter) Read(dst []byte) (int, error) { + n, err := rw.IO.CopyIn(rw.Ctx, rw.Addr, dst, rw.Opts) + end, ok := rw.Addr.AddLength(uint64(n)) + if ok { + rw.Addr = end + } else { + // Disallow wraparound. + rw.Addr = ^Addr(0) + if err != nil { + err = syserror.EFAULT + } + } + return n, err +} + +// Writer implements io.Writer.Write. +func (rw *IOReadWriter) Write(src []byte) (int, error) { + n, err := rw.IO.CopyOut(rw.Ctx, rw.Addr, src, rw.Opts) + end, ok := rw.Addr.AddLength(uint64(n)) + if ok { + rw.Addr = end + } else { + // Disallow wraparound. + rw.Addr = ^Addr(0) + if err != nil { + err = syserror.EFAULT + } + } + return n, err +} + +// CopyObjectOut copies a fixed-size value or slice of fixed-size values from +// src to the memory mapped at addr in uio. It returns the number of bytes +// copied. +// +// CopyObjectOut must use reflection to encode src; performance-sensitive +// clients should do encoding manually and use uio.CopyOut directly. +// +// Preconditions: As for IO.CopyOut. +func CopyObjectOut(ctx context.Context, uio IO, addr Addr, src interface{}, opts IOOpts) (int, error) { + w := &IOReadWriter{ + Ctx: ctx, + IO: uio, + Addr: addr, + Opts: opts, + } + // Allocate a byte slice the size of the object being marshaled. This + // adds an extra reflection call, but avoids needing to grow the slice + // during encoding, which can result in many heap-allocated slices. + b := make([]byte, 0, binary.Size(src)) + return w.Write(binary.Marshal(b, ByteOrder, src)) +} + +// CopyObjectIn copies a fixed-size value or slice of fixed-size values from +// the memory mapped at addr in uio to dst. It returns the number of bytes +// copied. +// +// CopyObjectIn must use reflection to decode dst; performance-sensitive +// clients should use uio.CopyIn directly and do decoding manually. +// +// Preconditions: As for IO.CopyIn. +func CopyObjectIn(ctx context.Context, uio IO, addr Addr, dst interface{}, opts IOOpts) (int, error) { + r := &IOReadWriter{ + Ctx: ctx, + IO: uio, + Addr: addr, + Opts: opts, + } + buf := make([]byte, binary.Size(dst)) + if _, err := io.ReadFull(r, buf); err != nil { + return 0, err + } + binary.Unmarshal(buf, ByteOrder, dst) + return int(r.Addr - addr), nil +} + +// CopyStringIn tuning parameters, defined outside that function for tests. +const ( + copyStringIncrement = 64 + copyStringMaxInitBufLen = 256 +) + +// CopyStringIn copies a NUL-terminated string of unknown length from the +// memory mapped at addr in uio and returns it as a string (not including the +// trailing NUL). If the length of the string, including the terminating NUL, +// would exceed maxlen, CopyStringIn returns the string truncated to maxlen and +// ENAMETOOLONG. +// +// Preconditions: As for IO.CopyFromUser. maxlen >= 0. +func CopyStringIn(ctx context.Context, uio IO, addr Addr, maxlen int, opts IOOpts) (string, error) { + initLen := maxlen + if initLen > copyStringMaxInitBufLen { + initLen = copyStringMaxInitBufLen + } + buf := make([]byte, initLen) + var done int + for done < maxlen { + // Read up to copyStringIncrement bytes at a time. + readlen := copyStringIncrement + if readlen > maxlen-done { + readlen = maxlen - done + } + end, ok := addr.AddLength(uint64(readlen)) + if !ok { + return stringFromImmutableBytes(buf[:done]), syserror.EFAULT + } + // Shorten the read to avoid crossing page boundaries, since faulting + // in a page unnecessarily is expensive. This also ensures that partial + // copies up to the end of application-mappable memory succeed. + if addr.RoundDown() != end.RoundDown() { + end = end.RoundDown() + readlen = int(end - addr) + } + // Ensure that our buffer is large enough to accommodate the read. + if done+readlen > len(buf) { + newBufLen := len(buf) * 2 + if newBufLen > maxlen { + newBufLen = maxlen + } + buf = append(buf, make([]byte, newBufLen-len(buf))...) + } + n, err := uio.CopyIn(ctx, addr, buf[done:done+readlen], opts) + // Look for the terminating zero byte, which may have occurred before + // hitting err. + if i := bytes.IndexByte(buf[done:done+n], byte(0)); i >= 0 { + return stringFromImmutableBytes(buf[:done+i]), nil + } + + done += n + if err != nil { + return stringFromImmutableBytes(buf[:done]), err + } + addr = end + } + return stringFromImmutableBytes(buf), syserror.ENAMETOOLONG +} + +// CopyOutVec copies bytes from src to the memory mapped at ars in uio. The +// maximum number of bytes copied is ars.NumBytes() or len(src), whichever is +// less. CopyOutVec returns the number of bytes copied; if this is less than +// the maximum, it returns a non-nil error explaining why. +// +// Preconditions: As for IO.CopyOut. +func CopyOutVec(ctx context.Context, uio IO, ars AddrRangeSeq, src []byte, opts IOOpts) (int, error) { + var done int + for !ars.IsEmpty() && done < len(src) { + ar := ars.Head() + cplen := len(src) - done + if Addr(cplen) >= ar.Length() { + cplen = int(ar.Length()) + } + n, err := uio.CopyOut(ctx, ar.Start, src[done:done+cplen], opts) + done += n + if err != nil { + return done, err + } + ars = ars.DropFirst(n) + } + return done, nil +} + +// CopyInVec copies bytes from the memory mapped at ars in uio to dst. The +// maximum number of bytes copied is ars.NumBytes() or len(dst), whichever is +// less. CopyInVec returns the number of bytes copied; if this is less than the +// maximum, it returns a non-nil error explaining why. +// +// Preconditions: As for IO.CopyIn. +func CopyInVec(ctx context.Context, uio IO, ars AddrRangeSeq, dst []byte, opts IOOpts) (int, error) { + var done int + for !ars.IsEmpty() && done < len(dst) { + ar := ars.Head() + cplen := len(dst) - done + if Addr(cplen) >= ar.Length() { + cplen = int(ar.Length()) + } + n, err := uio.CopyIn(ctx, ar.Start, dst[done:done+cplen], opts) + done += n + if err != nil { + return done, err + } + ars = ars.DropFirst(n) + } + return done, nil +} + +// ZeroOutVec writes zeroes to the memory mapped at ars in uio. The maximum +// number of bytes written is ars.NumBytes() or toZero, whichever is less. +// ZeroOutVec returns the number of bytes written; if this is less than the +// maximum, it returns a non-nil error explaining why. +// +// Preconditions: As for IO.ZeroOut. +func ZeroOutVec(ctx context.Context, uio IO, ars AddrRangeSeq, toZero int64, opts IOOpts) (int64, error) { + var done int64 + for !ars.IsEmpty() && done < toZero { + ar := ars.Head() + cplen := toZero - done + if Addr(cplen) >= ar.Length() { + cplen = int64(ar.Length()) + } + n, err := uio.ZeroOut(ctx, ar.Start, cplen, opts) + done += n + if err != nil { + return done, err + } + ars = ars.DropFirst64(n) + } + return done, nil +} + +func isASCIIWhitespace(b byte) bool { + // Compare Linux include/linux/ctype.h, lib/ctype.c. + // 9 => horizontal tab '\t' + // 10 => line feed '\n' + // 11 => vertical tab '\v' + // 12 => form feed '\c' + // 13 => carriage return '\r' + return b == ' ' || (b >= 9 && b <= 13) +} + +// CopyInt32StringsInVec copies up to len(dsts) whitespace-separated decimal +// strings from the memory mapped at ars in uio and converts them to int32 +// values in dsts. It returns the number of bytes read. +// +// CopyInt32StringsInVec shares the following properties with Linux's +// kernel/sysctl.c:proc_dointvec(write=1): +// +// - If any read value overflows the range of int32, or any invalid characters +// are encountered during the read, CopyInt32StringsInVec returns EINVAL. +// +// - If, upon reaching the end of ars, fewer than len(dsts) values have been +// read, CopyInt32StringsInVec returns no error if at least 1 value was read +// and EINVAL otherwise. +// +// - Trailing whitespace after the last successfully read value is counted in +// the number of bytes read. +// +// Unlike proc_dointvec(): +// +// - CopyInt32StringsInVec does not implicitly limit ars.NumBytes() to +// PageSize-1; callers that require this must do so explicitly. +// +// - CopyInt32StringsInVec returns EINVAL if ars.NumBytes() == 0. +// +// Preconditions: As for CopyInVec. +func CopyInt32StringsInVec(ctx context.Context, uio IO, ars AddrRangeSeq, dsts []int32, opts IOOpts) (int64, error) { + if len(dsts) == 0 { + return 0, nil + } + + buf := make([]byte, ars.NumBytes()) + n, cperr := CopyInVec(ctx, uio, ars, buf, opts) + buf = buf[:n] + + var i, j int + for ; j < len(dsts); j++ { + // Skip leading whitespace. + for i < len(buf) && isASCIIWhitespace(buf[i]) { + i++ + } + if i == len(buf) { + break + } + + // Find the end of the value to be parsed (next whitespace or end of string). + nextI := i + 1 + for nextI < len(buf) && !isASCIIWhitespace(buf[nextI]) { + nextI++ + } + + // Parse a single value. + val, err := strconv.ParseInt(string(buf[i:nextI]), 10, 32) + if err != nil { + return int64(i), syserror.EINVAL + } + dsts[j] = int32(val) + + i = nextI + } + + // Skip trailing whitespace. + for i < len(buf) && isASCIIWhitespace(buf[i]) { + i++ + } + + if cperr != nil { + return int64(i), cperr + } + if j == 0 { + return int64(i), syserror.EINVAL + } + return int64(i), nil +} + +// CopyInt32StringInVec is equivalent to CopyInt32StringsInVec, but copies at +// most one int32. +func CopyInt32StringInVec(ctx context.Context, uio IO, ars AddrRangeSeq, dst *int32, opts IOOpts) (int64, error) { + dsts := [1]int32{*dst} + n, err := CopyInt32StringsInVec(ctx, uio, ars, dsts[:], opts) + *dst = dsts[0] + return n, err +} + +// IOSequence holds arguments to IO methods. +type IOSequence struct { + IO IO + Addrs AddrRangeSeq + Opts IOOpts +} + +// NumBytes returns s.Addrs.NumBytes(). +// +// Note that NumBytes() may return 0 even if !s.Addrs.IsEmpty(), since +// s.Addrs may contain a non-zero number of zero-length AddrRanges. +// Many clients of +// IOSequence currently do something like: +// +// if ioseq.NumBytes() == 0 { +// return 0, nil +// } +// if f.availableBytes == 0 { +// return 0, syserror.ErrWouldBlock +// } +// return ioseq.CopyOutFrom(..., reader) +// +// In such cases, using s.Addrs.IsEmpty() will cause them to have the wrong +// behavior for zero-length I/O. However, using s.NumBytes() == 0 instead means +// that we will return success for zero-length I/O in cases where Linux would +// return EFAULT due to a failed access_ok() check, so in the long term we +// should move checks for ErrWouldBlock etc. into the body of +// reader.ReadToBlocks and use s.Addrs.IsEmpty() instead. +func (s IOSequence) NumBytes() int64 { + return s.Addrs.NumBytes() +} + +// DropFirst returns a copy of s with s.Addrs.DropFirst(n). +// +// Preconditions: As for AddrRangeSeq.DropFirst. +func (s IOSequence) DropFirst(n int) IOSequence { + return IOSequence{s.IO, s.Addrs.DropFirst(n), s.Opts} +} + +// DropFirst64 returns a copy of s with s.Addrs.DropFirst64(n). +// +// Preconditions: As for AddrRangeSeq.DropFirst64. +func (s IOSequence) DropFirst64(n int64) IOSequence { + return IOSequence{s.IO, s.Addrs.DropFirst64(n), s.Opts} +} + +// TakeFirst returns a copy of s with s.Addrs.TakeFirst(n). +// +// Preconditions: As for AddrRangeSeq.TakeFirst. +func (s IOSequence) TakeFirst(n int) IOSequence { + return IOSequence{s.IO, s.Addrs.TakeFirst(n), s.Opts} +} + +// TakeFirst64 returns a copy of s with s.Addrs.TakeFirst64(n). +// +// Preconditions: As for AddrRangeSeq.TakeFirst64. +func (s IOSequence) TakeFirst64(n int64) IOSequence { + return IOSequence{s.IO, s.Addrs.TakeFirst64(n), s.Opts} +} + +// CopyOut invokes CopyOutVec over s.Addrs. +// +// As with CopyOutVec, if s.NumBytes() < len(src), the copy will be truncated +// to s.NumBytes(), and a nil error will be returned. +// +// Preconditions: As for CopyOutVec. +func (s IOSequence) CopyOut(ctx context.Context, src []byte) (int, error) { + return CopyOutVec(ctx, s.IO, s.Addrs, src, s.Opts) +} + +// CopyIn invokes CopyInVec over s.Addrs. +// +// As with CopyInVec, if s.NumBytes() < len(dst), the copy will be truncated to +// s.NumBytes(), and a nil error will be returned. +// +// Preconditions: As for CopyInVec. +func (s IOSequence) CopyIn(ctx context.Context, dst []byte) (int, error) { + return CopyInVec(ctx, s.IO, s.Addrs, dst, s.Opts) +} + +// ZeroOut invokes ZeroOutVec over s.Addrs. +// +// As with ZeroOutVec, if s.NumBytes() < toZero, the write will be truncated +// to s.NumBytes(), and a nil error will be returned. +// +// Preconditions: As for ZeroOutVec. +func (s IOSequence) ZeroOut(ctx context.Context, toZero int64) (int64, error) { + return ZeroOutVec(ctx, s.IO, s.Addrs, toZero, s.Opts) +} + +// CopyOutFrom invokes s.CopyOutFrom over s.Addrs. +// +// Preconditions: As for IO.CopyOutFrom. +func (s IOSequence) CopyOutFrom(ctx context.Context, src safemem.Reader) (int64, error) { + return s.IO.CopyOutFrom(ctx, s.Addrs, src, s.Opts) +} + +// CopyInTo invokes s.CopyInTo over s.Addrs. +// +// Preconditions: As for IO.CopyInTo. +func (s IOSequence) CopyInTo(ctx context.Context, dst safemem.Writer) (int64, error) { + return s.IO.CopyInTo(ctx, s.Addrs, dst, s.Opts) +} + +// Reader returns an io.Reader that reads from s. Reads beyond the end of s +// return io.EOF. The preconditions that apply to s.CopyIn also apply to the +// returned io.Reader.Read. +func (s IOSequence) Reader(ctx context.Context) io.Reader { + return &ioSequenceReadWriter{ctx, s} +} + +// Writer returns an io.Writer that writes to s. Writes beyond the end of s +// return ErrEndOfIOSequence. The preconditions that apply to s.CopyOut also +// apply to the returned io.Writer.Write. +func (s IOSequence) Writer(ctx context.Context) io.Writer { + return &ioSequenceReadWriter{ctx, s} +} + +// ErrEndOfIOSequence is returned by IOSequence.Writer().Write() when +// attempting to write beyond the end of the IOSequence. +var ErrEndOfIOSequence = errors.New("write beyond end of IOSequence") + +type ioSequenceReadWriter struct { + ctx context.Context + s IOSequence +} + +// Read implements io.Reader.Read. +func (rw *ioSequenceReadWriter) Read(dst []byte) (int, error) { + n, err := rw.s.CopyIn(rw.ctx, dst) + rw.s = rw.s.DropFirst(n) + if err == nil && rw.s.NumBytes() == 0 { + err = io.EOF + } + return n, err +} + +// Write implements io.Writer.Write. +func (rw *ioSequenceReadWriter) Write(src []byte) (int, error) { + n, err := rw.s.CopyOut(rw.ctx, src) + rw.s = rw.s.DropFirst(n) + if err == nil && n < len(src) { + err = ErrEndOfIOSequence + } + return n, err +} diff --git a/pkg/usermem/usermem_arm64.go b/pkg/usermem/usermem_arm64.go new file mode 100644 index 000000000..fdfc30a66 --- /dev/null +++ b/pkg/usermem/usermem_arm64.go @@ -0,0 +1,53 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// +build arm64 + +package usermem + +import ( + "encoding/binary" + "syscall" +) + +const ( + // PageSize is the system page size. + // arm64 support 4K/16K/64K page size, + // which can be get by syscall.Getpagesize(). + // Currently, only 4K page size is supported. + PageSize = 1 << PageShift + + // HugePageSize is the system huge page size. + HugePageSize = 1 << HugePageShift + + // PageShift is the binary log of the system page size. + PageShift = 12 + + // HugePageShift is the binary log of the system huge page size. + // Should be calculated by "PageShift + (PageShift - 3)" + // when multiple page size support is ready. + HugePageShift = 21 +) + +var ( + // ByteOrder is the native byte order (little endian). + ByteOrder = binary.LittleEndian +) + +func init() { + // Make sure the page size is 4K on arm64 platform. + if size := syscall.Getpagesize(); size != PageSize { + panic("Only 4K page size is supported on arm64!") + } +} diff --git a/pkg/usermem/usermem_test.go b/pkg/usermem/usermem_test.go new file mode 100644 index 000000000..bf3c5df2b --- /dev/null +++ b/pkg/usermem/usermem_test.go @@ -0,0 +1,424 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package usermem + +import ( + "bytes" + "encoding/binary" + "fmt" + "reflect" + "strings" + "testing" + + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/safemem" + "gvisor.dev/gvisor/pkg/syserror" +) + +// newContext returns a context.Context that we can use in these tests (we +// can't use contexttest because it depends on usermem). +func newContext() context.Context { + return context.Background() +} + +func newBytesIOString(s string) *BytesIO { + return &BytesIO{[]byte(s)} +} + +func TestBytesIOCopyOutSuccess(t *testing.T) { + b := newBytesIOString("ABCDE") + n, err := b.CopyOut(newContext(), 1, []byte("foo"), IOOpts{}) + if wantN := 3; n != wantN || err != nil { + t.Errorf("CopyOut: got (%v, %v), wanted (%v, nil)", n, err, wantN) + } + if got, want := b.Bytes, []byte("AfooE"); !bytes.Equal(got, want) { + t.Errorf("Bytes: got %q, wanted %q", got, want) + } +} + +func TestBytesIOCopyOutFailure(t *testing.T) { + b := newBytesIOString("ABC") + n, err := b.CopyOut(newContext(), 1, []byte("foo"), IOOpts{}) + if wantN, wantErr := 2, syserror.EFAULT; n != wantN || err != wantErr { + t.Errorf("CopyOut: got (%v, %v), wanted (%v, %v)", n, err, wantN, wantErr) + } + if got, want := b.Bytes, []byte("Afo"); !bytes.Equal(got, want) { + t.Errorf("Bytes: got %q, wanted %q", got, want) + } +} + +func TestBytesIOCopyInSuccess(t *testing.T) { + b := newBytesIOString("AfooE") + var dst [3]byte + n, err := b.CopyIn(newContext(), 1, dst[:], IOOpts{}) + if wantN := 3; n != wantN || err != nil { + t.Errorf("CopyIn: got (%v, %v), wanted (%v, nil)", n, err, wantN) + } + if got, want := dst[:], []byte("foo"); !bytes.Equal(got, want) { + t.Errorf("dst: got %q, wanted %q", got, want) + } +} + +func TestBytesIOCopyInFailure(t *testing.T) { + b := newBytesIOString("Afo") + var dst [3]byte + n, err := b.CopyIn(newContext(), 1, dst[:], IOOpts{}) + if wantN, wantErr := 2, syserror.EFAULT; n != wantN || err != wantErr { + t.Errorf("CopyIn: got (%v, %v), wanted (%v, %v)", n, err, wantN, wantErr) + } + if got, want := dst[:], []byte("fo\x00"); !bytes.Equal(got, want) { + t.Errorf("dst: got %q, wanted %q", got, want) + } +} + +func TestBytesIOZeroOutSuccess(t *testing.T) { + b := newBytesIOString("ABCD") + n, err := b.ZeroOut(newContext(), 1, 2, IOOpts{}) + if wantN := int64(2); n != wantN || err != nil { + t.Errorf("ZeroOut: got (%v, %v), wanted (%v, nil)", n, err, wantN) + } + if got, want := b.Bytes, []byte("A\x00\x00D"); !bytes.Equal(got, want) { + t.Errorf("Bytes: got %q, wanted %q", got, want) + } +} + +func TestBytesIOZeroOutFailure(t *testing.T) { + b := newBytesIOString("ABC") + n, err := b.ZeroOut(newContext(), 1, 3, IOOpts{}) + if wantN, wantErr := int64(2), syserror.EFAULT; n != wantN || err != wantErr { + t.Errorf("ZeroOut: got (%v, %v), wanted (%v, %v)", n, err, wantN, wantErr) + } + if got, want := b.Bytes, []byte("A\x00\x00"); !bytes.Equal(got, want) { + t.Errorf("Bytes: got %q, wanted %q", got, want) + } +} + +func TestBytesIOCopyOutFromSuccess(t *testing.T) { + b := newBytesIOString("ABCDEFGH") + n, err := b.CopyOutFrom(newContext(), AddrRangeSeqFromSlice([]AddrRange{ + {Start: 4, End: 7}, + {Start: 1, End: 4}, + }), safemem.FromIOReader{bytes.NewBufferString("barfoo")}, IOOpts{}) + if wantN := int64(6); n != wantN || err != nil { + t.Errorf("CopyOutFrom: got (%v, %v), wanted (%v, nil)", n, err, wantN) + } + if got, want := b.Bytes, []byte("AfoobarH"); !bytes.Equal(got, want) { + t.Errorf("Bytes: got %q, wanted %q", got, want) + } +} + +func TestBytesIOCopyOutFromFailure(t *testing.T) { + b := newBytesIOString("ABCDE") + n, err := b.CopyOutFrom(newContext(), AddrRangeSeqFromSlice([]AddrRange{ + {Start: 1, End: 4}, + {Start: 4, End: 7}, + }), safemem.FromIOReader{bytes.NewBufferString("foobar")}, IOOpts{}) + if wantN, wantErr := int64(4), syserror.EFAULT; n != wantN || err != wantErr { + t.Errorf("CopyOutFrom: got (%v, %v), wanted (%v, %v)", n, err, wantN, wantErr) + } + if got, want := b.Bytes, []byte("Afoob"); !bytes.Equal(got, want) { + t.Errorf("Bytes: got %q, wanted %q", got, want) + } +} + +func TestBytesIOCopyInToSuccess(t *testing.T) { + b := newBytesIOString("AfoobarH") + var dst bytes.Buffer + n, err := b.CopyInTo(newContext(), AddrRangeSeqFromSlice([]AddrRange{ + {Start: 4, End: 7}, + {Start: 1, End: 4}, + }), safemem.FromIOWriter{&dst}, IOOpts{}) + if wantN := int64(6); n != wantN || err != nil { + t.Errorf("CopyInTo: got (%v, %v), wanted (%v, nil)", n, err, wantN) + } + if got, want := dst.Bytes(), []byte("barfoo"); !bytes.Equal(got, want) { + t.Errorf("dst.Bytes(): got %q, wanted %q", got, want) + } +} + +func TestBytesIOCopyInToFailure(t *testing.T) { + b := newBytesIOString("Afoob") + var dst bytes.Buffer + n, err := b.CopyInTo(newContext(), AddrRangeSeqFromSlice([]AddrRange{ + {Start: 1, End: 4}, + {Start: 4, End: 7}, + }), safemem.FromIOWriter{&dst}, IOOpts{}) + if wantN, wantErr := int64(4), syserror.EFAULT; n != wantN || err != wantErr { + t.Errorf("CopyOutFrom: got (%v, %v), wanted (%v, %v)", n, err, wantN, wantErr) + } + if got, want := dst.Bytes(), []byte("foob"); !bytes.Equal(got, want) { + t.Errorf("dst.Bytes(): got %q, wanted %q", got, want) + } +} + +type testStruct struct { + Int8 int8 + Uint8 uint8 + Int16 int16 + Uint16 uint16 + Int32 int32 + Uint32 uint32 + Int64 int64 + Uint64 uint64 +} + +func TestCopyObject(t *testing.T) { + wantObj := testStruct{1, 2, 3, 4, 5, 6, 7, 8} + wantN := binary.Size(wantObj) + b := &BytesIO{make([]byte, wantN)} + ctx := newContext() + if n, err := CopyObjectOut(ctx, b, 0, &wantObj, IOOpts{}); n != wantN || err != nil { + t.Fatalf("CopyObjectOut: got (%v, %v), wanted (%v, nil)", n, err, wantN) + } + var gotObj testStruct + if n, err := CopyObjectIn(ctx, b, 0, &gotObj, IOOpts{}); n != wantN || err != nil { + t.Errorf("CopyObjectIn: got (%v, %v), wanted (%v, nil)", n, err, wantN) + } + if gotObj != wantObj { + t.Errorf("CopyObject round trip: got %+v, wanted %+v", gotObj, wantObj) + } +} + +func TestCopyStringInShort(t *testing.T) { + // Tests for string length <= copyStringIncrement. + want := strings.Repeat("A", copyStringIncrement-2) + mem := want + "\x00" + if got, err := CopyStringIn(newContext(), newBytesIOString(mem), 0, 2*copyStringIncrement, IOOpts{}); got != want || err != nil { + t.Errorf("CopyStringIn: got (%q, %v), wanted (%q, nil)", got, err, want) + } +} + +func TestCopyStringInLong(t *testing.T) { + // Tests for copyStringIncrement < string length <= copyStringMaxInitBufLen + // (requiring multiple calls to IO.CopyIn()). + want := strings.Repeat("A", copyStringIncrement*3/4) + strings.Repeat("B", copyStringIncrement*3/4) + mem := want + "\x00" + if got, err := CopyStringIn(newContext(), newBytesIOString(mem), 0, 2*copyStringIncrement, IOOpts{}); got != want || err != nil { + t.Errorf("CopyStringIn: got (%q, %v), wanted (%q, nil)", got, err, want) + } +} + +func TestCopyStringInVeryLong(t *testing.T) { + // Tests for string length > copyStringMaxInitBufLen (requiring buffer + // reallocation). + want := strings.Repeat("A", copyStringMaxInitBufLen*3/4) + strings.Repeat("B", copyStringMaxInitBufLen*3/4) + mem := want + "\x00" + if got, err := CopyStringIn(newContext(), newBytesIOString(mem), 0, 2*copyStringMaxInitBufLen, IOOpts{}); got != want || err != nil { + t.Errorf("CopyStringIn: got (%q, %v), wanted (%q, nil)", got, err, want) + } +} + +func TestCopyStringInNoTerminatingZeroByte(t *testing.T) { + want := strings.Repeat("A", copyStringIncrement-1) + got, err := CopyStringIn(newContext(), newBytesIOString(want), 0, 2*copyStringIncrement, IOOpts{}) + if wantErr := syserror.EFAULT; got != want || err != wantErr { + t.Errorf("CopyStringIn: got (%q, %v), wanted (%q, %v)", got, err, want, wantErr) + } +} + +func TestCopyStringInTruncatedByMaxlen(t *testing.T) { + got, err := CopyStringIn(newContext(), newBytesIOString(strings.Repeat("A", 10)), 0, 5, IOOpts{}) + if want, wantErr := strings.Repeat("A", 5), syserror.ENAMETOOLONG; got != want || err != wantErr { + t.Errorf("CopyStringIn: got (%q, %v), wanted (%q, %v)", got, err, want, wantErr) + } +} + +func TestCopyInt32StringsInVec(t *testing.T) { + for _, test := range []struct { + str string + n int + initial []int32 + final []int32 + }{ + { + str: "100 200", + n: len("100 200"), + initial: []int32{1, 2}, + final: []int32{100, 200}, + }, + { + // Fewer values ok + str: "100", + n: len("100"), + initial: []int32{1, 2}, + final: []int32{100, 2}, + }, + { + // Extra values ok + str: "100 200 300", + n: len("100 200 "), + initial: []int32{1, 2}, + final: []int32{100, 200}, + }, + { + // Leading and trailing whitespace ok + str: " 100\t200\n", + n: len(" 100\t200\n"), + initial: []int32{1, 2}, + final: []int32{100, 200}, + }, + } { + t.Run(fmt.Sprintf("%q", test.str), func(t *testing.T) { + src := BytesIOSequence([]byte(test.str)) + dsts := append([]int32(nil), test.initial...) + if n, err := CopyInt32StringsInVec(newContext(), src.IO, src.Addrs, dsts, src.Opts); n != int64(test.n) || err != nil { + t.Errorf("CopyInt32StringsInVec: got (%d, %v), wanted (%d, nil)", n, err, test.n) + } + if !reflect.DeepEqual(dsts, test.final) { + t.Errorf("dsts: got %v, wanted %v", dsts, test.final) + } + }) + } +} + +func TestCopyInt32StringsInVecRequiresOneValidValue(t *testing.T) { + for _, s := range []string{"", "\n", "a123"} { + t.Run(fmt.Sprintf("%q", s), func(t *testing.T) { + src := BytesIOSequence([]byte(s)) + initial := []int32{1, 2} + dsts := append([]int32(nil), initial...) + if n, err := CopyInt32StringsInVec(newContext(), src.IO, src.Addrs, dsts, src.Opts); err != syserror.EINVAL { + t.Errorf("CopyInt32StringsInVec: got (%d, %v), wanted (_, %v)", n, err, syserror.EINVAL) + } + if !reflect.DeepEqual(dsts, initial) { + t.Errorf("dsts: got %v, wanted %v", dsts, initial) + } + }) + } +} + +func TestIOSequenceCopyOut(t *testing.T) { + buf := []byte("ABCD") + s := BytesIOSequence(buf) + + // CopyOut limited by len(src). + n, err := s.CopyOut(newContext(), []byte("fo")) + if wantN := 2; n != wantN || err != nil { + t.Errorf("CopyOut: got (%v, %v), wanted (%v, nil)", n, err, wantN) + } + if want := []byte("foCD"); !bytes.Equal(buf, want) { + t.Errorf("buf: got %q, wanted %q", buf, want) + } + s = s.DropFirst(2) + if got, want := s.NumBytes(), int64(2); got != want { + t.Errorf("NumBytes: got %v, wanted %v", got, want) + } + + // CopyOut limited by s.NumBytes(). + n, err = s.CopyOut(newContext(), []byte("obar")) + if wantN := 2; n != wantN || err != nil { + t.Errorf("CopyOut: got (%v, %v), wanted (%v, nil)", n, err, wantN) + } + if want := []byte("foob"); !bytes.Equal(buf, want) { + t.Errorf("buf: got %q, wanted %q", buf, want) + } + s = s.DropFirst(2) + if got, want := s.NumBytes(), int64(0); got != want { + t.Errorf("NumBytes: got %v, wanted %v", got, want) + } +} + +func TestIOSequenceCopyIn(t *testing.T) { + s := BytesIOSequence([]byte("foob")) + dst := []byte("ABCDEF") + + // CopyIn limited by len(dst). + n, err := s.CopyIn(newContext(), dst[:2]) + if wantN := 2; n != wantN || err != nil { + t.Errorf("CopyIn: got (%v, %v), wanted (%v, nil)", n, err, wantN) + } + if want := []byte("foCDEF"); !bytes.Equal(dst, want) { + t.Errorf("dst: got %q, wanted %q", dst, want) + } + s = s.DropFirst(2) + if got, want := s.NumBytes(), int64(2); got != want { + t.Errorf("NumBytes: got %v, wanted %v", got, want) + } + + // CopyIn limited by s.Remaining(). + n, err = s.CopyIn(newContext(), dst[2:]) + if wantN := 2; n != wantN || err != nil { + t.Errorf("CopyIn: got (%v, %v), wanted (%v, nil)", n, err, wantN) + } + if want := []byte("foobEF"); !bytes.Equal(dst, want) { + t.Errorf("dst: got %q, wanted %q", dst, want) + } + s = s.DropFirst(2) + if got, want := s.NumBytes(), int64(0); got != want { + t.Errorf("NumBytes: got %v, wanted %v", got, want) + } +} + +func TestIOSequenceZeroOut(t *testing.T) { + buf := []byte("ABCD") + s := BytesIOSequence(buf) + + // ZeroOut limited by toZero. + n, err := s.ZeroOut(newContext(), 2) + if wantN := int64(2); n != wantN || err != nil { + t.Errorf("ZeroOut: got (%v, %v), wanted (%v, nil)", n, err, wantN) + } + if want := []byte("\x00\x00CD"); !bytes.Equal(buf, want) { + t.Errorf("buf: got %q, wanted %q", buf, want) + } + s = s.DropFirst(2) + if got, want := s.NumBytes(), int64(2); got != want { + t.Errorf("NumBytes: got %v, wanted %v", got, want) + } + + // ZeroOut limited by s.NumBytes(). + n, err = s.ZeroOut(newContext(), 4) + if wantN := int64(2); n != wantN || err != nil { + t.Errorf("CopyOut: got (%v, %v), wanted (%v, nil)", n, err, wantN) + } + if want := []byte("\x00\x00\x00\x00"); !bytes.Equal(buf, want) { + t.Errorf("buf: got %q, wanted %q", buf, want) + } + s = s.DropFirst(2) + if got, want := s.NumBytes(), int64(0); got != want { + t.Errorf("NumBytes: got %v, wanted %v", got, want) + } +} + +func TestIOSequenceTakeFirst(t *testing.T) { + s := BytesIOSequence([]byte("foobar")) + if got, want := s.NumBytes(), int64(6); got != want { + t.Errorf("NumBytes: got %v, wanted %v", got, want) + } + + s = s.TakeFirst(3) + if got, want := s.NumBytes(), int64(3); got != want { + t.Errorf("NumBytes: got %v, wanted %v", got, want) + } + + // TakeFirst(n) where n > s.NumBytes() is a no-op. + s = s.TakeFirst(9) + if got, want := s.NumBytes(), int64(3); got != want { + t.Errorf("NumBytes: got %v, wanted %v", got, want) + } + + var dst [3]byte + n, err := s.CopyIn(newContext(), dst[:]) + if wantN := 3; n != wantN || err != nil { + t.Errorf("CopyIn: got (%v, %v), wanted (%v, nil)", n, err, wantN) + } + if got, want := dst[:], []byte("foo"); !bytes.Equal(got, want) { + t.Errorf("dst: got %q, wanted %q", got, want) + } + s = s.DropFirst(3) + if got, want := s.NumBytes(), int64(0); got != want { + t.Errorf("NumBytes: got %v, wanted %v", got, want) + } +} diff --git a/pkg/usermem/usermem_unsafe.go b/pkg/usermem/usermem_unsafe.go new file mode 100644 index 000000000..876783e78 --- /dev/null +++ b/pkg/usermem/usermem_unsafe.go @@ -0,0 +1,27 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package usermem + +import ( + "unsafe" +) + +// stringFromImmutableBytes is equivalent to string(bs), except that it never +// copies even if escape analysis can't prove that bs does not escape. This is +// only valid if bs is never mutated after stringFromImmutableBytes returns. +func stringFromImmutableBytes(bs []byte) string { + // Compare strings.Builder.String(). + return *(*string)(unsafe.Pointer(&bs)) +} diff --git a/pkg/usermem/usermem_x86.go b/pkg/usermem/usermem_x86.go new file mode 100644 index 000000000..8059b72d2 --- /dev/null +++ b/pkg/usermem/usermem_x86.go @@ -0,0 +1,38 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// +build amd64 i386 + +package usermem + +import "encoding/binary" + +const ( + // PageSize is the system page size. + PageSize = 1 << PageShift + + // HugePageSize is the system huge page size. + HugePageSize = 1 << HugePageShift + + // PageShift is the binary log of the system page size. + PageShift = 12 + + // HugePageShift is the binary log of the system huge page size. + HugePageShift = 21 +) + +var ( + // ByteOrder is the native byte order (little endian). + ByteOrder = binary.LittleEndian +) diff --git a/runsc/boot/BUILD b/runsc/boot/BUILD index f3ebc0231..a96c80261 100644 --- a/runsc/boot/BUILD +++ b/runsc/boot/BUILD @@ -30,6 +30,7 @@ go_library( deps = [ "//pkg/abi", "//pkg/abi/linux", + "//pkg/context", "//pkg/control/server", "//pkg/cpuid", "//pkg/eventchannel", @@ -39,7 +40,6 @@ go_library( "//pkg/refs", "//pkg/sentry/arch", "//pkg/sentry/arch:registers_go_proto", - "//pkg/sentry/context", "//pkg/sentry/control", "//pkg/sentry/fs", "//pkg/sentry/fs/dev", @@ -71,7 +71,6 @@ go_library( "//pkg/sentry/time", "//pkg/sentry/unimpl:unimplemented_syscall_go_proto", "//pkg/sentry/usage", - "//pkg/sentry/usermem", "//pkg/sentry/watchdog", "//pkg/sync", "//pkg/syserror", @@ -88,6 +87,7 @@ go_library( "//pkg/tcpip/transport/tcp", "//pkg/tcpip/transport/udp", "//pkg/urpc", + "//pkg/usermem", "//runsc/boot/filter", "//runsc/boot/platforms", "//runsc/specutils", @@ -111,7 +111,7 @@ go_test( "//pkg/control/server", "//pkg/log", "//pkg/p9", - "//pkg/sentry/context/contexttest", + "//pkg/sentry/contexttest", "//pkg/sentry/fs", "//pkg/sentry/kernel/auth", "//pkg/sync", diff --git a/runsc/boot/fds.go b/runsc/boot/fds.go index e5de1f3d7..417d2d5fb 100644 --- a/runsc/boot/fds.go +++ b/runsc/boot/fds.go @@ -17,7 +17,7 @@ package boot import ( "fmt" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/host" "gvisor.dev/gvisor/pkg/sentry/kernel" diff --git a/runsc/boot/fs.go b/runsc/boot/fs.go index 421ccd255..0f62842ea 100644 --- a/runsc/boot/fs.go +++ b/runsc/boot/fs.go @@ -32,8 +32,8 @@ import ( specs "github.com/opencontainers/runtime-spec/specs-go" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/log" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/gofer" "gvisor.dev/gvisor/pkg/sentry/fs/ramfs" diff --git a/runsc/boot/loader_test.go b/runsc/boot/loader_test.go index bec0dc292..44aa63196 100644 --- a/runsc/boot/loader_test.go +++ b/runsc/boot/loader_test.go @@ -27,7 +27,7 @@ import ( "gvisor.dev/gvisor/pkg/control/server" "gvisor.dev/gvisor/pkg/log" "gvisor.dev/gvisor/pkg/p9" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/unet" diff --git a/runsc/boot/user.go b/runsc/boot/user.go index 56cc12ee0..f0aa52135 100644 --- a/runsc/boot/user.go +++ b/runsc/boot/user.go @@ -22,10 +22,10 @@ import ( "strings" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) type fileReader struct { diff --git a/runsc/boot/user_test.go b/runsc/boot/user_test.go index 9aee2ad07..fb4e13dfb 100644 --- a/runsc/boot/user_test.go +++ b/runsc/boot/user_test.go @@ -23,7 +23,7 @@ import ( "testing" specs "github.com/opencontainers/runtime-spec/specs-go" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" ) diff --git a/tools/go_marshal/defs.bzl b/tools/go_marshal/defs.bzl index 2918ceffe..d79786a68 100644 --- a/tools/go_marshal/defs.bzl +++ b/tools/go_marshal/defs.bzl @@ -54,8 +54,8 @@ go_marshal = rule( # marshal_deps are the dependencies requied by generated code. marshal_deps = [ "//tools/go_marshal/marshal", - "//pkg/sentry/platform/safecopy", - "//pkg/sentry/usermem", + "//pkg/safecopy", + "//pkg/usermem", ] # marshal_test_deps are required by test targets. diff --git a/tools/go_marshal/gomarshal/generator.go b/tools/go_marshal/gomarshal/generator.go index 8392f3f6d..af90bdecb 100644 --- a/tools/go_marshal/gomarshal/generator.go +++ b/tools/go_marshal/gomarshal/generator.go @@ -27,8 +27,8 @@ import ( const ( marshalImport = "gvisor.dev/gvisor/tools/go_marshal/marshal" - usermemImport = "gvisor.dev/gvisor/pkg/sentry/usermem" - safecopyImport = "gvisor.dev/gvisor/pkg/sentry/platform/safecopy" + safecopyImport = "gvisor.dev/gvisor/pkg/safecopy" + usermemImport = "gvisor.dev/gvisor/pkg/usermem" ) // List of identifiers we use in generated code, that may conflict a diff --git a/tools/go_marshal/test/BUILD b/tools/go_marshal/test/BUILD index 38ba49fed..e345e3a8e 100644 --- a/tools/go_marshal/test/BUILD +++ b/tools/go_marshal/test/BUILD @@ -15,7 +15,7 @@ go_test( deps = [ ":test", "//pkg/binary", - "//pkg/sentry/usermem", + "//pkg/usermem", "//tools/go_marshal/analysis", ], ) diff --git a/tools/go_marshal/test/benchmark_test.go b/tools/go_marshal/test/benchmark_test.go index e70db06d8..e12403741 100644 --- a/tools/go_marshal/test/benchmark_test.go +++ b/tools/go_marshal/test/benchmark_test.go @@ -22,7 +22,7 @@ import ( "testing" "gvisor.dev/gvisor/pkg/binary" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/tools/go_marshal/analysis" test "gvisor.dev/gvisor/tools/go_marshal/test" ) -- cgit v1.2.3 From 492229d0176c1af2ab4ea4cf91bf211e940b5b12 Mon Sep 17 00:00:00 2001 From: Jamie Liu Date: Tue, 4 Feb 2020 11:28:36 -0800 Subject: VFS2 gofer client Updates #1198 Opening host pipes (by spinning in fdpipe) and host sockets is not yet complete, and will be done in a future CL. Major differences from VFS1 gofer client (sentry/fs/gofer), with varying levels of backportability: - "Cache policies" are replaced by InteropMode, which control the behavior of timestamps in addition to caching. Under InteropModeExclusive (analogous to cacheAll) and InteropModeWritethrough (analogous to cacheAllWritethrough), client timestamps are *not* written back to the server (it is not possible in 9P or Linux for clients to set ctime, so writing back client-authoritative timestamps results in incoherence between atime/mtime and ctime). Under InteropModeShared (analogous to cacheRemoteRevalidating), client timestamps are not used at all (remote filesystem clocks are authoritative). cacheNone is translated to InteropModeShared + new option filesystemOptions.specialRegularFiles. - Under InteropModeShared, "unstable attribute" reloading for permission checks, lookup, and revalidation are fused, which is feasible in VFS2 since gofer.filesystem controls path resolution. This results in a ~33% reduction in RPCs for filesystem operations compared to cacheRemoteRevalidating. For example, consider stat("/foo/bar/baz") where "/foo/bar/baz" fails revalidation, resulting in the instantiation of a new dentry: VFS1 RPCs: getattr("/") // fs.MountNamespace.FindLink() => fs.Inode.CheckPermission() => gofer.inodeOperations.check() => gofer.inodeOperations.UnstableAttr() walkgetattr("/", "foo") = fid1 // fs.Dirent.walk() => gofer.session.Revalidate() => gofer.cachePolicy.Revalidate() clunk(fid1) getattr("/foo") // CheckPermission walkgetattr("/foo", "bar") = fid2 // Revalidate clunk(fid2) getattr("/foo/bar") // CheckPermission walkgetattr("/foo/bar", "baz") = fid3 // Revalidate clunk(fid3) walkgetattr("/foo/bar", "baz") = fid4 // fs.Dirent.walk() => gofer.inodeOperations.Lookup getattr("/foo/bar/baz") // linux.stat() => gofer.inodeOperations.UnstableAttr() VFS2 RPCs: getattr("/") // gofer.filesystem.walkExistingLocked() walkgetattr("/", "foo") = fid1 // gofer.filesystem.stepExistingLocked() clunk(fid1) // No getattr: walkgetattr already updated metadata for permission check walkgetattr("/foo", "bar") = fid2 clunk(fid2) walkgetattr("/foo/bar", "baz") = fid3 // No clunk: fid3 used for new gofer.dentry // No getattr: walkgetattr already updated metadata for stat() - gofer.filesystem.unlinkAt() does not require instantiation of a dentry that represents the file to be deleted. Updates #898. - gofer.regularFileFD.OnClose() skips Tflushf for regular files under InteropModeExclusive, as it's nonsensical to request a remote file flush without flushing locally-buffered writes to that remote file first. - Symlink targets are cached when InteropModeShared is not in effect. - p9.QID.Path (which is already required to be unique for each file within a server, and is accordingly already synthesized from device/inode numbers in all known gofers) is used as-is for inode numbers, rather than being mapped along with attr.RDev in the client to yet another synthetic inode number. - Relevant parts of fsutil.CachingInodeOperations are inlined directly into gofer package code. This avoids having to duplicate part of its functionality in fsutil.HostMappable. PiperOrigin-RevId: 293190213 --- pkg/safemem/seq_unsafe.go | 17 + pkg/sentry/fs/fsutil/BUILD | 4 +- pkg/sentry/fs/fsutil/frame_ref_set.go | 13 +- pkg/sentry/fs/fsutil/inode_cached.go | 2 +- pkg/sentry/fsimpl/gofer/BUILD | 55 ++ pkg/sentry/fsimpl/gofer/directory.go | 190 +++++ pkg/sentry/fsimpl/gofer/filesystem.go | 1087 ++++++++++++++++++++++++++++ pkg/sentry/fsimpl/gofer/gofer.go | 1147 ++++++++++++++++++++++++++++++ pkg/sentry/fsimpl/gofer/handle.go | 135 ++++ pkg/sentry/fsimpl/gofer/handle_unsafe.go | 66 ++ pkg/sentry/fsimpl/gofer/p9file.go | 219 ++++++ pkg/sentry/fsimpl/gofer/pagemath.go | 31 + pkg/sentry/fsimpl/gofer/regular_file.go | 860 ++++++++++++++++++++++ pkg/sentry/fsimpl/gofer/special_file.go | 159 +++++ pkg/sentry/fsimpl/gofer/symlink.go | 47 ++ pkg/sentry/fsimpl/gofer/time.go | 75 ++ pkg/sentry/fsimpl/tmpfs/filesystem.go | 2 +- pkg/sentry/socket/hostinet/socket.go | 23 +- 18 files changed, 4103 insertions(+), 29 deletions(-) create mode 100644 pkg/sentry/fsimpl/gofer/BUILD create mode 100644 pkg/sentry/fsimpl/gofer/directory.go create mode 100644 pkg/sentry/fsimpl/gofer/filesystem.go create mode 100644 pkg/sentry/fsimpl/gofer/gofer.go create mode 100644 pkg/sentry/fsimpl/gofer/handle.go create mode 100644 pkg/sentry/fsimpl/gofer/handle_unsafe.go create mode 100644 pkg/sentry/fsimpl/gofer/p9file.go create mode 100644 pkg/sentry/fsimpl/gofer/pagemath.go create mode 100644 pkg/sentry/fsimpl/gofer/regular_file.go create mode 100644 pkg/sentry/fsimpl/gofer/special_file.go create mode 100644 pkg/sentry/fsimpl/gofer/symlink.go create mode 100644 pkg/sentry/fsimpl/gofer/time.go (limited to 'pkg/sentry/fsimpl/tmpfs/filesystem.go') diff --git a/pkg/safemem/seq_unsafe.go b/pkg/safemem/seq_unsafe.go index 354a95dde..dcdfc9600 100644 --- a/pkg/safemem/seq_unsafe.go +++ b/pkg/safemem/seq_unsafe.go @@ -18,6 +18,7 @@ import ( "bytes" "fmt" "reflect" + "syscall" "unsafe" ) @@ -297,3 +298,19 @@ func ZeroSeq(dsts BlockSeq) (uint64, error) { } return done, nil } + +// IovecsFromBlockSeq returns a []syscall.Iovec representing seq. +func IovecsFromBlockSeq(bs BlockSeq) []syscall.Iovec { + iovs := make([]syscall.Iovec, 0, bs.NumBlocks()) + for ; !bs.IsEmpty(); bs = bs.Tail() { + b := bs.Head() + iovs = append(iovs, syscall.Iovec{ + Base: &b.ToSlice()[0], + Len: uint64(b.Len()), + }) + // We don't need to care about b.NeedSafecopy(), because the host + // kernel will handle such address ranges just fine (by returning + // EFAULT). + } + return iovs +} diff --git a/pkg/sentry/fs/fsutil/BUILD b/pkg/sentry/fs/fsutil/BUILD index 4ab2a384f..789369220 100644 --- a/pkg/sentry/fs/fsutil/BUILD +++ b/pkg/sentry/fs/fsutil/BUILD @@ -28,13 +28,13 @@ go_template_instance( "platform": "gvisor.dev/gvisor/pkg/sentry/platform", }, package = "fsutil", - prefix = "frameRef", + prefix = "FrameRef", template = "//pkg/segment:generic_set", types = { "Key": "uint64", "Range": "platform.FileRange", "Value": "uint64", - "Functions": "frameRefSetFunctions", + "Functions": "FrameRefSetFunctions", }, ) diff --git a/pkg/sentry/fs/fsutil/frame_ref_set.go b/pkg/sentry/fs/fsutil/frame_ref_set.go index dd63db32b..6564fd0c6 100644 --- a/pkg/sentry/fs/fsutil/frame_ref_set.go +++ b/pkg/sentry/fs/fsutil/frame_ref_set.go @@ -20,24 +20,25 @@ import ( "gvisor.dev/gvisor/pkg/sentry/platform" ) -type frameRefSetFunctions struct{} +// FrameRefSetFunctions implements segment.Functions for FrameRefSet. +type FrameRefSetFunctions struct{} // MinKey implements segment.Functions.MinKey. -func (frameRefSetFunctions) MinKey() uint64 { +func (FrameRefSetFunctions) MinKey() uint64 { return 0 } // MaxKey implements segment.Functions.MaxKey. -func (frameRefSetFunctions) MaxKey() uint64 { +func (FrameRefSetFunctions) MaxKey() uint64 { return math.MaxUint64 } // ClearValue implements segment.Functions.ClearValue. -func (frameRefSetFunctions) ClearValue(val *uint64) { +func (FrameRefSetFunctions) ClearValue(val *uint64) { } // Merge implements segment.Functions.Merge. -func (frameRefSetFunctions) Merge(_ platform.FileRange, val1 uint64, _ platform.FileRange, val2 uint64) (uint64, bool) { +func (FrameRefSetFunctions) Merge(_ platform.FileRange, val1 uint64, _ platform.FileRange, val2 uint64) (uint64, bool) { if val1 != val2 { return 0, false } @@ -45,6 +46,6 @@ func (frameRefSetFunctions) Merge(_ platform.FileRange, val1 uint64, _ platform. } // Split implements segment.Functions.Split. -func (frameRefSetFunctions) Split(_ platform.FileRange, val uint64, _ uint64) (uint64, uint64) { +func (FrameRefSetFunctions) Split(_ platform.FileRange, val uint64, _ uint64) (uint64, uint64) { return val, val } diff --git a/pkg/sentry/fs/fsutil/inode_cached.go b/pkg/sentry/fs/fsutil/inode_cached.go index 573b8586e..800c8b4e1 100644 --- a/pkg/sentry/fs/fsutil/inode_cached.go +++ b/pkg/sentry/fs/fsutil/inode_cached.go @@ -111,7 +111,7 @@ type CachingInodeOperations struct { // refs tracks active references to data in the cache. // // refs is protected by dataMu. - refs frameRefSet + refs FrameRefSet } // CachingInodeOperationsOptions configures a CachingInodeOperations. diff --git a/pkg/sentry/fsimpl/gofer/BUILD b/pkg/sentry/fsimpl/gofer/BUILD new file mode 100644 index 000000000..4ba76a1e8 --- /dev/null +++ b/pkg/sentry/fsimpl/gofer/BUILD @@ -0,0 +1,55 @@ +load("//tools:defs.bzl", "go_library") +load("//tools/go_generics:defs.bzl", "go_template_instance") + +licenses(["notice"]) + +go_template_instance( + name = "dentry_list", + out = "dentry_list.go", + package = "gofer", + prefix = "dentry", + template = "//pkg/ilist:generic_list", + types = { + "Element": "*dentry", + "Linker": "*dentry", + }, +) + +go_library( + name = "gofer", + srcs = [ + "dentry_list.go", + "directory.go", + "filesystem.go", + "gofer.go", + "handle.go", + "handle_unsafe.go", + "p9file.go", + "pagemath.go", + "regular_file.go", + "special_file.go", + "symlink.go", + "time.go", + ], + visibility = ["//pkg/sentry:internal"], + deps = [ + "//pkg/abi/linux", + "//pkg/context", + "//pkg/fd", + "//pkg/fspath", + "//pkg/log", + "//pkg/p9", + "//pkg/safemem", + "//pkg/sentry/fs/fsutil", + "//pkg/sentry/kernel/auth", + "//pkg/sentry/kernel/time", + "//pkg/sentry/memmap", + "//pkg/sentry/pgalloc", + "//pkg/sentry/platform", + "//pkg/sentry/usage", + "//pkg/sentry/vfs", + "//pkg/syserror", + "//pkg/unet", + "//pkg/usermem", + ], +) diff --git a/pkg/sentry/fsimpl/gofer/directory.go b/pkg/sentry/fsimpl/gofer/directory.go new file mode 100644 index 000000000..baa2cdd8e --- /dev/null +++ b/pkg/sentry/fsimpl/gofer/directory.go @@ -0,0 +1,190 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package gofer + +import ( + "sync" + "sync/atomic" + + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/p9" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserror" +) + +func (d *dentry) isDir() bool { + return d.fileType() == linux.S_IFDIR +} + +// Preconditions: d.dirMu must be locked. d.isDir(). fs.opts.interop != +// InteropModeShared. +func (d *dentry) cacheNegativeChildLocked(name string) { + if d.negativeChildren == nil { + d.negativeChildren = make(map[string]struct{}) + } + d.negativeChildren[name] = struct{}{} +} + +type directoryFD struct { + fileDescription + vfs.DirectoryFileDescriptionDefaultImpl + + mu sync.Mutex + off int64 + dirents []vfs.Dirent +} + +// Release implements vfs.FileDescriptionImpl.Release. +func (fd *directoryFD) Release() { +} + +// IterDirents implements vfs.FileDescriptionImpl.IterDirents. +func (fd *directoryFD) IterDirents(ctx context.Context, cb vfs.IterDirentsCallback) error { + fd.mu.Lock() + defer fd.mu.Unlock() + + if fd.dirents == nil { + ds, err := fd.dentry().getDirents(ctx) + if err != nil { + return err + } + fd.dirents = ds + } + + for fd.off < int64(len(fd.dirents)) { + if !cb.Handle(fd.dirents[fd.off]) { + return nil + } + fd.off++ + } + return nil +} + +// Preconditions: d.isDir(). There exists at least one directoryFD representing d. +func (d *dentry) getDirents(ctx context.Context) ([]vfs.Dirent, error) { + // 9P2000.L's readdir does not specify behavior in the presence of + // concurrent mutation of an iterated directory, so implementations may + // duplicate or omit entries in this case, which violates POSIX semantics. + // Thus we read all directory entries while holding d.dirMu to exclude + // directory mutations. (Note that it is impossible for the client to + // exclude concurrent mutation from other remote filesystem users. Since + // there is no way to detect if the server has incorrectly omitted + // directory entries, we simply assume that the server is well-behaved + // under InteropModeShared.) This is inconsistent with Linux (which appears + // to assume that directory fids have the correct semantics, and translates + // struct file_operations::readdir calls directly to readdir RPCs), but is + // consistent with VFS1. + + d.fs.renameMu.RLock() + defer d.fs.renameMu.RUnlock() + d.dirMu.Lock() + defer d.dirMu.Unlock() + if d.dirents != nil { + return d.dirents, nil + } + + // It's not clear if 9P2000.L's readdir is expected to return "." and "..", + // so we generate them here. + parent := d.vfsd.ParentOrSelf().Impl().(*dentry) + dirents := []vfs.Dirent{ + { + Name: ".", + Type: linux.DT_DIR, + Ino: d.ino, + NextOff: 1, + }, + { + Name: "..", + Type: uint8(atomic.LoadUint32(&parent.mode) >> 12), + Ino: parent.ino, + NextOff: 2, + }, + } + off := uint64(0) + const count = 64 * 1024 // for consistency with the vfs1 client + d.handleMu.RLock() + defer d.handleMu.RUnlock() + if !d.handleReadable { + // This should not be possible because a readable handle should have + // been opened when the calling directoryFD was opened. + panic("gofer.dentry.getDirents called without a readable handle") + } + for { + p9ds, err := d.handle.file.readdir(ctx, off, count) + if err != nil { + return nil, err + } + if len(p9ds) == 0 { + // Cache dirents for future directoryFDs if permitted. + if d.fs.opts.interop != InteropModeShared { + d.dirents = dirents + } + return dirents, nil + } + for _, p9d := range p9ds { + if p9d.Name == "." || p9d.Name == ".." { + continue + } + dirent := vfs.Dirent{ + Name: p9d.Name, + Ino: p9d.QID.Path, + NextOff: int64(len(dirents) + 1), + } + // p9 does not expose 9P2000.U's DMDEVICE, DMNAMEDPIPE, or + // DMSOCKET. + switch p9d.Type { + case p9.TypeSymlink: + dirent.Type = linux.DT_LNK + case p9.TypeDir: + dirent.Type = linux.DT_DIR + default: + dirent.Type = linux.DT_REG + } + dirents = append(dirents, dirent) + } + off = p9ds[len(p9ds)-1].Offset + } +} + +// Seek implements vfs.FileDescriptionImpl.Seek. +func (fd *directoryFD) Seek(ctx context.Context, offset int64, whence int32) (int64, error) { + fd.mu.Lock() + defer fd.mu.Unlock() + + switch whence { + case linux.SEEK_SET: + if offset < 0 { + return 0, syserror.EINVAL + } + if offset == 0 { + // Ensure that the next call to fd.IterDirents() calls + // fd.dentry().getDirents(). + fd.dirents = nil + } + fd.off = offset + return fd.off, nil + case linux.SEEK_CUR: + offset += fd.off + if offset < 0 { + return 0, syserror.EINVAL + } + // Don't clear fd.dirents in this case, even if offset == 0. + fd.off = offset + return fd.off, nil + default: + return 0, syserror.EINVAL + } +} diff --git a/pkg/sentry/fsimpl/gofer/filesystem.go b/pkg/sentry/fsimpl/gofer/filesystem.go new file mode 100644 index 000000000..8eb61debf --- /dev/null +++ b/pkg/sentry/fsimpl/gofer/filesystem.go @@ -0,0 +1,1087 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package gofer + +import ( + "sync" + + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/fspath" + "gvisor.dev/gvisor/pkg/p9" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserror" +) + +// Sync implements vfs.FilesystemImpl.Sync. +func (fs *filesystem) Sync(ctx context.Context) error { + // Snapshot current dentries and special files. + fs.syncMu.Lock() + ds := make([]*dentry, 0, len(fs.dentries)) + for d := range fs.dentries { + ds = append(ds, d) + } + sffds := make([]*specialFileFD, 0, len(fs.specialFileFDs)) + for sffd := range fs.specialFileFDs { + sffds = append(sffds, sffd) + } + fs.syncMu.Unlock() + + // Return the first error we encounter, but sync everything we can + // regardless. + var retErr error + + // Sync regular files. + for _, d := range ds { + if !d.TryIncRef() { + continue + } + err := d.syncSharedHandle(ctx) + d.DecRef() + if err != nil && retErr == nil { + retErr = err + } + } + + // Sync special files, which may be writable but do not use dentry shared + // handles (so they won't be synced by the above). + for _, sffd := range sffds { + if !sffd.vfsfd.TryIncRef() { + continue + } + err := sffd.Sync(ctx) + sffd.vfsfd.DecRef() + if err != nil && retErr == nil { + retErr = err + } + } + + return retErr +} + +// maxFilenameLen is the maximum length of a filename. This is dictated by 9P's +// encoding of strings, which uses 2 bytes for the length prefix. +const maxFilenameLen = (1 << 16) - 1 + +// dentrySlicePool is a pool of *[]*dentry used to store dentries for which +// dentry.checkCachingLocked() must be called. The pool holds pointers to +// slices because Go lacks generics, so sync.Pool operates on interface{}, so +// every call to (what should be) sync.Pool<[]*dentry>.Put() allocates a copy +// of the slice header on the heap. +var dentrySlicePool = sync.Pool{ + New: func() interface{} { + ds := make([]*dentry, 0, 4) // arbitrary non-zero initial capacity + return &ds + }, +} + +func appendDentry(ds *[]*dentry, d *dentry) *[]*dentry { + if ds == nil { + ds = dentrySlicePool.Get().(*[]*dentry) + } + *ds = append(*ds, d) + return ds +} + +// Preconditions: ds != nil. +func putDentrySlice(ds *[]*dentry) { + // Allow dentries to be GC'd. + for i := range *ds { + (*ds)[i] = nil + } + *ds = (*ds)[:0] + dentrySlicePool.Put(ds) +} + +// stepLocked resolves rp.Component() to an existing file, starting from the +// given directory. +// +// Dentries which may become cached as a result of the traversal are appended +// to *ds. +// +// Preconditions: fs.renameMu must be locked. d.dirMu must be locked. +// !rp.Done(). If fs.opts.interop == InteropModeShared, then d's cached +// metadata must be up to date. +func (fs *filesystem) stepLocked(ctx context.Context, rp *vfs.ResolvingPath, d *dentry, ds **[]*dentry) (*dentry, error) { + if !d.isDir() { + return nil, syserror.ENOTDIR + } + if err := d.checkPermissions(rp.Credentials(), vfs.MayExec, true); err != nil { + return nil, err + } +afterSymlink: + name := rp.Component() + if name == "." { + rp.Advance() + return d, nil + } + if name == ".." { + parentVFSD, err := rp.ResolveParent(&d.vfsd) + if err != nil { + return nil, err + } + parent := parentVFSD.Impl().(*dentry) + if fs.opts.interop == InteropModeShared { + // We must assume that parentVFSD is correct, because if d has been + // moved elsewhere in the remote filesystem so that its parent has + // changed, we have no way of determining its new parent's location + // in the filesystem. Get updated metadata for parentVFSD. + _, attrMask, attr, err := parent.file.getAttr(ctx, dentryAttrMask()) + if err != nil { + return nil, err + } + parent.updateFromP9Attrs(attrMask, &attr) + } + rp.Advance() + return parent, nil + } + childVFSD, err := rp.ResolveChild(&d.vfsd, name) + if err != nil { + return nil, err + } + // FIXME(jamieliu): Linux performs revalidation before mount lookup + // (fs/namei.c:lookup_fast() => __d_lookup_rcu(), d_revalidate(), + // __follow_mount_rcu()). + child, err := fs.revalidateChildLocked(ctx, rp.VirtualFilesystem(), d, name, childVFSD, ds) + if err != nil { + return nil, err + } + if child == nil { + return nil, syserror.ENOENT + } + if child.isSymlink() && rp.ShouldFollowSymlink() { + target, err := child.readlink(ctx, rp.Mount()) + if err != nil { + return nil, err + } + if err := rp.HandleSymlink(target); err != nil { + return nil, err + } + goto afterSymlink // don't check the current directory again + } + rp.Advance() + return child, nil +} + +// revalidateChildLocked must be called after a call to parent.vfsd.Child(name) +// or vfs.ResolvingPath.ResolveChild(name) returns childVFSD (which may be +// nil) to verify that the returned child (or lack thereof) is correct. If no file +// exists at name, revalidateChildLocked returns (nil, nil). +// +// Preconditions: fs.renameMu must be locked. parent.dirMu must be locked. +// parent.isDir(). name is not "." or "..". +// +// Postconditions: If revalidateChildLocked returns a non-nil dentry, its +// cached metadata is up to date. +func (fs *filesystem) revalidateChildLocked(ctx context.Context, vfsObj *vfs.VirtualFilesystem, parent *dentry, name string, childVFSD *vfs.Dentry, ds **[]*dentry) (*dentry, error) { + if childVFSD != nil && fs.opts.interop != InteropModeShared { + // We have a cached dentry that is assumed to be correct. + return childVFSD.Impl().(*dentry), nil + } + // We either don't have a cached dentry or need to verify that it's still + // correct, either of which requires a remote lookup. Check if this name is + // valid before performing the lookup. + if len(name) > maxFilenameLen { + return nil, syserror.ENAMETOOLONG + } + // Check if we've already cached this lookup with a negative result. + if _, ok := parent.negativeChildren[name]; ok { + return nil, nil + } + // Perform the remote lookup. + qid, file, attrMask, attr, err := parent.file.walkGetAttrOne(ctx, name) + if err != nil && err != syserror.ENOENT { + return nil, err + } + if childVFSD != nil { + child := childVFSD.Impl().(*dentry) + if !file.isNil() && qid.Path == child.ino { + // The file at this path hasn't changed. Just update cached + // metadata. + file.close(ctx) + child.updateFromP9Attrs(attrMask, &attr) + return child, nil + } + // The file at this path has changed or no longer exists. Remove + // the stale dentry from the tree, and re-evaluate its caching + // status (i.e. if it has 0 references, drop it). + vfsObj.ForceDeleteDentry(childVFSD) + *ds = appendDentry(*ds, child) + childVFSD = nil + } + if file.isNil() { + // No file exists at this path now. Cache the negative lookup if + // allowed. + if fs.opts.interop != InteropModeShared { + parent.cacheNegativeChildLocked(name) + } + return nil, nil + } + // Create a new dentry representing the file. + child, err := fs.newDentry(ctx, file, qid, attrMask, &attr) + if err != nil { + file.close(ctx) + return nil, err + } + parent.IncRef() // reference held by child on its parent + parent.vfsd.InsertChild(&child.vfsd, name) + // For now, child has 0 references, so our caller should call + // child.checkCachingLocked(). + *ds = appendDentry(*ds, child) + return child, nil +} + +// walkParentDirLocked resolves all but the last path component of rp to an +// existing directory, starting from the given directory (which is usually +// rp.Start().Impl().(*dentry)). It does not check that the returned directory +// is searchable by the provider of rp. +// +// Preconditions: fs.renameMu must be locked. !rp.Done(). If fs.opts.interop == +// InteropModeShared, then d's cached metadata must be up to date. +func (fs *filesystem) walkParentDirLocked(ctx context.Context, rp *vfs.ResolvingPath, d *dentry, ds **[]*dentry) (*dentry, error) { + for !rp.Final() { + d.dirMu.Lock() + next, err := fs.stepLocked(ctx, rp, d, ds) + d.dirMu.Unlock() + if err != nil { + return nil, err + } + d = next + } + if !d.isDir() { + return nil, syserror.ENOTDIR + } + return d, nil +} + +// resolveLocked resolves rp to an existing file. +// +// Preconditions: fs.renameMu must be locked. +func (fs *filesystem) resolveLocked(ctx context.Context, rp *vfs.ResolvingPath, ds **[]*dentry) (*dentry, error) { + d := rp.Start().Impl().(*dentry) + if fs.opts.interop == InteropModeShared { + // Get updated metadata for rp.Start() as required by fs.stepLocked(). + if err := d.updateFromGetattr(ctx); err != nil { + return nil, err + } + } + for !rp.Done() { + d.dirMu.Lock() + next, err := fs.stepLocked(ctx, rp, d, ds) + d.dirMu.Unlock() + if err != nil { + return nil, err + } + d = next + } + if rp.MustBeDir() && !d.isDir() { + return nil, syserror.ENOTDIR + } + return d, nil +} + +// doCreateAt checks that creating a file at rp is permitted, then invokes +// create to do so. +// +// Preconditions: !rp.Done(). For the final path component in rp, +// !rp.ShouldFollowSymlink(). +func (fs *filesystem) doCreateAt(ctx context.Context, rp *vfs.ResolvingPath, dir bool, create func(parent *dentry, name string) error) error { + var ds *[]*dentry + fs.renameMu.RLock() + defer fs.renameMuRUnlockAndCheckCaching(&ds) + start := rp.Start().Impl().(*dentry) + if fs.opts.interop == InteropModeShared { + // Get updated metadata for start as required by + // fs.walkParentDirLocked(). + if err := start.updateFromGetattr(ctx); err != nil { + return err + } + } + parent, err := fs.walkParentDirLocked(ctx, rp, start, &ds) + if err != nil { + return err + } + if err := parent.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec, true); err != nil { + return err + } + if parent.isDeleted() { + return syserror.ENOENT + } + name := rp.Component() + if name == "." || name == ".." { + return syserror.EEXIST + } + if len(name) > maxFilenameLen { + return syserror.ENAMETOOLONG + } + if !dir && rp.MustBeDir() { + return syserror.ENOENT + } + mnt := rp.Mount() + if err := mnt.CheckBeginWrite(); err != nil { + return err + } + defer mnt.EndWrite() + parent.dirMu.Lock() + defer parent.dirMu.Unlock() + if fs.opts.interop == InteropModeShared { + // The existence of a dentry at name would be inconclusive because the + // file it represents may have been deleted from the remote filesystem, + // so we would need to make an RPC to revalidate the dentry. Just + // attempt the file creation RPC instead. If a file does exist, the RPC + // will fail with EEXIST like we would have. If the RPC succeeds, and a + // stale dentry exists, the dentry will fail revalidation next time + // it's used. + return create(parent, name) + } + if parent.vfsd.Child(name) != nil { + return syserror.EEXIST + } + // No cached dentry exists; however, there might still be an existing file + // at name. As above, we attempt the file creation RPC anyway. + if err := create(parent, name); err != nil { + return err + } + parent.touchCMtime(ctx) + delete(parent.negativeChildren, name) + parent.dirents = nil + return nil +} + +// Preconditions: !rp.Done(). +func (fs *filesystem) unlinkAt(ctx context.Context, rp *vfs.ResolvingPath, dir bool) error { + var ds *[]*dentry + fs.renameMu.RLock() + defer fs.renameMuRUnlockAndCheckCaching(&ds) + start := rp.Start().Impl().(*dentry) + if fs.opts.interop == InteropModeShared { + // Get updated metadata for start as required by + // fs.walkParentDirLocked(). + if err := start.updateFromGetattr(ctx); err != nil { + return err + } + } + parent, err := fs.walkParentDirLocked(ctx, rp, start, &ds) + if err != nil { + return err + } + if err := parent.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec, true); err != nil { + return err + } + if err := rp.Mount().CheckBeginWrite(); err != nil { + return err + } + defer rp.Mount().EndWrite() + + name := rp.Component() + if dir { + if name == "." { + return syserror.EINVAL + } + if name == ".." { + return syserror.ENOTEMPTY + } + } else { + if name == "." || name == ".." { + return syserror.EISDIR + } + } + vfsObj := rp.VirtualFilesystem() + mntns := vfs.MountNamespaceFromContext(ctx) + parent.dirMu.Lock() + defer parent.dirMu.Unlock() + childVFSD := parent.vfsd.Child(name) + var child *dentry + // We only need a dentry representing the file at name if it can be a mount + // point. If childVFSD is nil, then it can't be a mount point. If childVFSD + // is non-nil but stale, the actual file can't be a mount point either; we + // detect this case by just speculatively calling PrepareDeleteDentry and + // only revalidating the dentry if that fails (indicating that the existing + // dentry is a mount point). + if childVFSD != nil { + child = childVFSD.Impl().(*dentry) + if err := vfsObj.PrepareDeleteDentry(mntns, childVFSD); err != nil { + child, err = fs.revalidateChildLocked(ctx, vfsObj, parent, name, childVFSD, &ds) + if err != nil { + return err + } + if child != nil { + childVFSD = &child.vfsd + if err := vfsObj.PrepareDeleteDentry(mntns, childVFSD); err != nil { + return err + } + } else { + childVFSD = nil + } + } + } else if _, ok := parent.negativeChildren[name]; ok { + return syserror.ENOENT + } + flags := uint32(0) + if dir { + if child != nil && !child.isDir() { + return syserror.ENOTDIR + } + flags = linux.AT_REMOVEDIR + } else { + if child != nil && child.isDir() { + return syserror.EISDIR + } + if rp.MustBeDir() { + return syserror.ENOTDIR + } + } + err = parent.file.unlinkAt(ctx, name, flags) + if err != nil { + if childVFSD != nil { + vfsObj.AbortDeleteDentry(childVFSD) + } + return err + } + if fs.opts.interop != InteropModeShared { + parent.touchCMtime(ctx) + parent.cacheNegativeChildLocked(name) + parent.dirents = nil + } + if child != nil { + child.setDeleted() + vfsObj.CommitDeleteDentry(childVFSD) + ds = appendDentry(ds, child) + } + return nil +} + +// renameMuRUnlockAndCheckCaching calls fs.renameMu.RUnlock(), then calls +// dentry.checkCachingLocked on all dentries in *ds with fs.renameMu locked for +// writing. +// +// ds is a pointer-to-pointer since defer evaluates its arguments immediately, +// but dentry slices are allocated lazily, and it's much easier to say "defer +// fs.renameMuRUnlockAndCheckCaching(&ds)" than "defer func() { +// fs.renameMuRUnlockAndCheckCaching(ds) }()" to work around this. +func (fs *filesystem) renameMuRUnlockAndCheckCaching(ds **[]*dentry) { + fs.renameMu.RUnlock() + if *ds == nil { + return + } + if len(**ds) != 0 { + fs.renameMu.Lock() + for _, d := range **ds { + d.checkCachingLocked() + } + fs.renameMu.Unlock() + } + putDentrySlice(*ds) +} + +func (fs *filesystem) renameMuUnlockAndCheckCaching(ds **[]*dentry) { + if *ds == nil { + fs.renameMu.Unlock() + return + } + for _, d := range **ds { + d.checkCachingLocked() + } + fs.renameMu.Unlock() + putDentrySlice(*ds) +} + +// GetDentryAt implements vfs.FilesystemImpl.GetDentryAt. +func (fs *filesystem) GetDentryAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.GetDentryOptions) (*vfs.Dentry, error) { + var ds *[]*dentry + fs.renameMu.RLock() + defer fs.renameMuRUnlockAndCheckCaching(&ds) + d, err := fs.resolveLocked(ctx, rp, &ds) + if err != nil { + return nil, err + } + if opts.CheckSearchable { + if !d.isDir() { + return nil, syserror.ENOTDIR + } + if err := d.checkPermissions(rp.Credentials(), vfs.MayExec, true); err != nil { + return nil, err + } + } + d.IncRef() + return &d.vfsd, nil +} + +// GetParentDentryAt implements vfs.FilesystemImpl.GetParentDentryAt. +func (fs *filesystem) GetParentDentryAt(ctx context.Context, rp *vfs.ResolvingPath) (*vfs.Dentry, error) { + var ds *[]*dentry + fs.renameMu.RLock() + defer fs.renameMuRUnlockAndCheckCaching(&ds) + start := rp.Start().Impl().(*dentry) + if fs.opts.interop == InteropModeShared { + // Get updated metadata for start as required by + // fs.walkParentDirLocked(). + if err := start.updateFromGetattr(ctx); err != nil { + return nil, err + } + } + d, err := fs.walkParentDirLocked(ctx, rp, start, &ds) + if err != nil { + return nil, err + } + d.IncRef() + return &d.vfsd, nil +} + +// LinkAt implements vfs.FilesystemImpl.LinkAt. +func (fs *filesystem) LinkAt(ctx context.Context, rp *vfs.ResolvingPath, vd vfs.VirtualDentry) error { + return fs.doCreateAt(ctx, rp, false /* dir */, func(parent *dentry, childName string) error { + if rp.Mount() != vd.Mount() { + return syserror.EXDEV + } + // 9P2000.L supports hard links, but we don't. + return syserror.EPERM + }) +} + +// MkdirAt implements vfs.FilesystemImpl.MkdirAt. +func (fs *filesystem) MkdirAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.MkdirOptions) error { + return fs.doCreateAt(ctx, rp, true /* dir */, func(parent *dentry, name string) error { + creds := rp.Credentials() + _, err := parent.file.mkdir(ctx, name, (p9.FileMode)(opts.Mode), (p9.UID)(creds.EffectiveKUID), (p9.GID)(creds.EffectiveKGID)) + return err + }) +} + +// MknodAt implements vfs.FilesystemImpl.MknodAt. +func (fs *filesystem) MknodAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.MknodOptions) error { + return fs.doCreateAt(ctx, rp, false /* dir */, func(parent *dentry, name string) error { + creds := rp.Credentials() + _, err := parent.file.mknod(ctx, name, (p9.FileMode)(opts.Mode), opts.DevMajor, opts.DevMinor, (p9.UID)(creds.EffectiveKUID), (p9.GID)(creds.EffectiveKGID)) + return err + }) +} + +// OpenAt implements vfs.FilesystemImpl.OpenAt. +func (fs *filesystem) OpenAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.OpenOptions) (*vfs.FileDescription, error) { + // Reject O_TMPFILE, which is not supported; supporting it correctly in the + // presence of other remote filesystem users requires remote filesystem + // support, and it isn't clear that there's any way to implement this in + // 9P. + if opts.Flags&linux.O_TMPFILE != 0 { + return nil, syserror.EOPNOTSUPP + } + mayCreate := opts.Flags&linux.O_CREAT != 0 + mustCreate := opts.Flags&(linux.O_CREAT|linux.O_EXCL) == (linux.O_CREAT | linux.O_EXCL) + + var ds *[]*dentry + fs.renameMu.RLock() + defer fs.renameMuRUnlockAndCheckCaching(&ds) + + start := rp.Start().Impl().(*dentry) + if fs.opts.interop == InteropModeShared { + // Get updated metadata for start as required by fs.stepLocked(). + if err := start.updateFromGetattr(ctx); err != nil { + return nil, err + } + } + if rp.Done() { + return start.openLocked(ctx, rp, opts.Flags) + } + +afterTrailingSymlink: + parent, err := fs.walkParentDirLocked(ctx, rp, start, &ds) + if err != nil { + return nil, err + } + // Check for search permission in the parent directory. + if err := parent.checkPermissions(rp.Credentials(), vfs.MayExec, true); err != nil { + return nil, err + } + // Determine whether or not we need to create a file. + parent.dirMu.Lock() + child, err := fs.stepLocked(ctx, rp, parent, &ds) + if err == syserror.ENOENT && mayCreate { + fd, err := parent.createAndOpenChildLocked(ctx, rp, &opts) + parent.dirMu.Unlock() + return fd, err + } + if err != nil { + parent.dirMu.Unlock() + return nil, err + } + // Open existing child or follow symlink. + parent.dirMu.Unlock() + if mustCreate { + return nil, syserror.EEXIST + } + if child.isSymlink() && rp.ShouldFollowSymlink() { + target, err := child.readlink(ctx, rp.Mount()) + if err != nil { + return nil, err + } + if err := rp.HandleSymlink(target); err != nil { + return nil, err + } + start = parent + goto afterTrailingSymlink + } + return child.openLocked(ctx, rp, opts.Flags) +} + +// Preconditions: fs.renameMu must be locked. +func (d *dentry) openLocked(ctx context.Context, rp *vfs.ResolvingPath, flags uint32) (*vfs.FileDescription, error) { + ats := vfs.AccessTypesForOpenFlags(flags) + if err := d.checkPermissions(rp.Credentials(), ats, d.isDir()); err != nil { + return nil, err + } + mnt := rp.Mount() + filetype := d.fileType() + switch { + case filetype == linux.S_IFREG && !d.fs.opts.regularFilesUseSpecialFileFD: + if err := d.ensureSharedHandle(ctx, ats&vfs.MayRead != 0, ats&vfs.MayWrite != 0, flags&linux.O_TRUNC != 0); err != nil { + return nil, err + } + fd := ®ularFileFD{} + if err := fd.vfsfd.Init(fd, flags, mnt, &d.vfsd, &vfs.FileDescriptionOptions{ + AllowDirectIO: true, + }); err != nil { + return nil, err + } + return &fd.vfsfd, nil + case filetype == linux.S_IFDIR: + // Can't open directories with O_CREAT. + if flags&linux.O_CREAT != 0 { + return nil, syserror.EISDIR + } + // Can't open directories writably. + if ats&vfs.MayWrite != 0 { + return nil, syserror.EISDIR + } + if flags&linux.O_DIRECT != 0 { + return nil, syserror.EINVAL + } + if err := d.ensureSharedHandle(ctx, ats&vfs.MayRead != 0, false /* write */, false /* trunc */); err != nil { + return nil, err + } + fd := &directoryFD{} + if err := fd.vfsfd.Init(fd, flags, mnt, &d.vfsd, &vfs.FileDescriptionOptions{}); err != nil { + return nil, err + } + return &fd.vfsfd, nil + case filetype == linux.S_IFLNK: + // Can't open symlinks without O_PATH (which is unimplemented). + return nil, syserror.ELOOP + default: + if flags&linux.O_DIRECT != 0 { + return nil, syserror.EINVAL + } + h, err := openHandle(ctx, d.file, ats&vfs.MayRead != 0, ats&vfs.MayWrite != 0, flags&linux.O_TRUNC != 0) + if err != nil { + return nil, err + } + fd := &specialFileFD{ + handle: h, + } + if err := fd.vfsfd.Init(fd, flags, mnt, &d.vfsd, &vfs.FileDescriptionOptions{}); err != nil { + h.close(ctx) + return nil, err + } + return &fd.vfsfd, nil + } +} + +// Preconditions: d.fs.renameMu must be locked. d.dirMu must be locked. +func (d *dentry) createAndOpenChildLocked(ctx context.Context, rp *vfs.ResolvingPath, opts *vfs.OpenOptions) (*vfs.FileDescription, error) { + if err := d.checkPermissions(rp.Credentials(), vfs.MayWrite, true); err != nil { + return nil, err + } + if d.isDeleted() { + return nil, syserror.ENOENT + } + mnt := rp.Mount() + if err := mnt.CheckBeginWrite(); err != nil { + return nil, err + } + defer mnt.EndWrite() + + // 9P2000.L's lcreate takes a fid representing the parent directory, and + // converts it into an open fid representing the created file, so we need + // to duplicate the directory fid first. + _, dirfile, err := d.file.walk(ctx, nil) + if err != nil { + return nil, err + } + creds := rp.Credentials() + name := rp.Component() + fdobj, openFile, createQID, _, err := dirfile.create(ctx, name, (p9.OpenFlags)(opts.Flags), (p9.FileMode)(opts.Mode), (p9.UID)(creds.EffectiveKUID), (p9.GID)(creds.EffectiveKGID)) + if err != nil { + dirfile.close(ctx) + return nil, err + } + // Then we need to walk to the file we just created to get a non-open fid + // representing it, and to get its metadata. This must use d.file since, as + // explained above, dirfile was invalidated by dirfile.Create(). + walkQID, nonOpenFile, attrMask, attr, err := d.file.walkGetAttrOne(ctx, name) + if err != nil { + openFile.close(ctx) + if fdobj != nil { + fdobj.Close() + } + return nil, err + } + // Sanity-check that we walked to the file we created. + if createQID.Path != walkQID.Path { + // Probably due to concurrent remote filesystem mutation? + ctx.Warningf("gofer.dentry.createAndOpenChildLocked: created file has QID %v before walk, QID %v after (interop=%v)", createQID, walkQID, d.fs.opts.interop) + nonOpenFile.close(ctx) + openFile.close(ctx) + if fdobj != nil { + fdobj.Close() + } + return nil, syserror.EAGAIN + } + + // Construct the new dentry. + child, err := d.fs.newDentry(ctx, nonOpenFile, createQID, attrMask, &attr) + if err != nil { + nonOpenFile.close(ctx) + openFile.close(ctx) + if fdobj != nil { + fdobj.Close() + } + return nil, err + } + // Incorporate the fid that was opened by lcreate. + useRegularFileFD := child.fileType() == linux.S_IFREG && !d.fs.opts.regularFilesUseSpecialFileFD + if useRegularFileFD { + child.handleMu.Lock() + child.handle.file = openFile + if fdobj != nil { + child.handle.fd = int32(fdobj.Release()) + } + child.handleReadable = vfs.MayReadFileWithOpenFlags(opts.Flags) + child.handleWritable = vfs.MayWriteFileWithOpenFlags(opts.Flags) + child.handleMu.Unlock() + } + // Take a reference on the new dentry to be held by the new file + // description. (This reference also means that the new dentry is not + // eligible for caching yet, so we don't need to append to a dentry slice.) + child.refs = 1 + // Insert the dentry into the tree. + d.IncRef() // reference held by child on its parent d + d.vfsd.InsertChild(&child.vfsd, name) + if d.fs.opts.interop != InteropModeShared { + d.touchCMtime(ctx) + delete(d.negativeChildren, name) + d.dirents = nil + } + + // Finally, construct a file description representing the created file. + var childVFSFD *vfs.FileDescription + mnt.IncRef() + if useRegularFileFD { + fd := ®ularFileFD{} + if err := fd.vfsfd.Init(fd, opts.Flags, mnt, &child.vfsd, &vfs.FileDescriptionOptions{ + AllowDirectIO: true, + }); err != nil { + return nil, err + } + childVFSFD = &fd.vfsfd + } else { + fd := &specialFileFD{ + handle: handle{ + file: openFile, + fd: -1, + }, + } + if fdobj != nil { + fd.handle.fd = int32(fdobj.Release()) + } + if err := fd.vfsfd.Init(fd, opts.Flags, mnt, &child.vfsd, &vfs.FileDescriptionOptions{}); err != nil { + fd.handle.close(ctx) + return nil, err + } + childVFSFD = &fd.vfsfd + } + return childVFSFD, nil +} + +// ReadlinkAt implements vfs.FilesystemImpl.ReadlinkAt. +func (fs *filesystem) ReadlinkAt(ctx context.Context, rp *vfs.ResolvingPath) (string, error) { + var ds *[]*dentry + fs.renameMu.RLock() + defer fs.renameMuRUnlockAndCheckCaching(&ds) + d, err := fs.resolveLocked(ctx, rp, &ds) + if err != nil { + return "", err + } + if !d.isSymlink() { + return "", syserror.EINVAL + } + return d.readlink(ctx, rp.Mount()) +} + +// RenameAt implements vfs.FilesystemImpl.RenameAt. +func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldParentVD vfs.VirtualDentry, oldName string, opts vfs.RenameOptions) error { + if opts.Flags != 0 { + // Requires 9P support. + return syserror.EINVAL + } + + var ds *[]*dentry + fs.renameMu.Lock() + defer fs.renameMuUnlockAndCheckCaching(&ds) + newParent, err := fs.walkParentDirLocked(ctx, rp, rp.Start().Impl().(*dentry), &ds) + if err != nil { + return err + } + newName := rp.Component() + if newName == "." || newName == ".." { + return syserror.EBUSY + } + mnt := rp.Mount() + if mnt != oldParentVD.Mount() { + return syserror.EXDEV + } + if err := mnt.CheckBeginWrite(); err != nil { + return err + } + defer mnt.EndWrite() + + oldParent := oldParentVD.Dentry().Impl().(*dentry) + if fs.opts.interop == InteropModeShared { + if err := oldParent.updateFromGetattr(ctx); err != nil { + return err + } + } + if err := oldParent.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec, true); err != nil { + return err + } + vfsObj := rp.VirtualFilesystem() + // We need a dentry representing the renamed file since, if it's a + // directory, we need to check for write permission on it. + oldParent.dirMu.Lock() + defer oldParent.dirMu.Unlock() + renamed, err := fs.revalidateChildLocked(ctx, vfsObj, oldParent, oldName, oldParent.vfsd.Child(oldName), &ds) + if err != nil { + return err + } + if renamed == nil { + return syserror.ENOENT + } + if renamed.isDir() { + if renamed == newParent || renamed.vfsd.IsAncestorOf(&newParent.vfsd) { + return syserror.EINVAL + } + if oldParent != newParent { + if err := renamed.checkPermissions(rp.Credentials(), vfs.MayWrite, true); err != nil { + return err + } + } + } else { + if opts.MustBeDir || rp.MustBeDir() { + return syserror.ENOTDIR + } + } + + if oldParent != newParent { + if err := newParent.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec, true); err != nil { + return err + } + newParent.dirMu.Lock() + defer newParent.dirMu.Unlock() + } + if newParent.isDeleted() { + return syserror.ENOENT + } + replacedVFSD := newParent.vfsd.Child(newName) + var replaced *dentry + // This is similar to unlinkAt, except: + // + // - We revalidate the replaced dentry unconditionally for simplicity. + // + // - If rp.MustBeDir(), then we need a dentry representing the replaced + // file regardless to confirm that it's a directory. + if replacedVFSD != nil || rp.MustBeDir() { + replaced, err = fs.revalidateChildLocked(ctx, vfsObj, newParent, newName, replacedVFSD, &ds) + if err != nil { + return err + } + if replaced != nil { + if replaced.isDir() { + if !renamed.isDir() { + return syserror.EISDIR + } + } else { + if rp.MustBeDir() || renamed.isDir() { + return syserror.ENOTDIR + } + } + replacedVFSD = &replaced.vfsd + } else { + replacedVFSD = nil + } + } + + if oldParent == newParent && oldName == newName { + return nil + } + if err := vfsObj.PrepareRenameDentry(vfs.MountNamespaceFromContext(ctx), &renamed.vfsd, replacedVFSD); err != nil { + return err + } + if err := renamed.file.rename(ctx, newParent.file, newName); err != nil { + vfsObj.AbortRenameDentry(&renamed.vfsd, replacedVFSD) + return err + } + if fs.opts.interop != InteropModeShared { + oldParent.cacheNegativeChildLocked(oldName) + oldParent.dirents = nil + delete(newParent.negativeChildren, newName) + newParent.dirents = nil + } + vfsObj.CommitRenameReplaceDentry(&renamed.vfsd, &newParent.vfsd, newName, replacedVFSD) + return nil +} + +// RmdirAt implements vfs.FilesystemImpl.RmdirAt. +func (fs *filesystem) RmdirAt(ctx context.Context, rp *vfs.ResolvingPath) error { + return fs.unlinkAt(ctx, rp, true /* dir */) +} + +// SetStatAt implements vfs.FilesystemImpl.SetStatAt. +func (fs *filesystem) SetStatAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.SetStatOptions) error { + var ds *[]*dentry + fs.renameMu.RLock() + defer fs.renameMuRUnlockAndCheckCaching(&ds) + d, err := fs.resolveLocked(ctx, rp, &ds) + if err != nil { + return err + } + return d.setStat(ctx, rp.Credentials(), &opts.Stat, rp.Mount()) +} + +// StatAt implements vfs.FilesystemImpl.StatAt. +func (fs *filesystem) StatAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.StatOptions) (linux.Statx, error) { + var ds *[]*dentry + fs.renameMu.RLock() + defer fs.renameMuRUnlockAndCheckCaching(&ds) + d, err := fs.resolveLocked(ctx, rp, &ds) + if err != nil { + return linux.Statx{}, err + } + // Since walking updates metadata for all traversed dentries under + // InteropModeShared, including the returned one, we can return cached + // metadata here regardless of fs.opts.interop. + var stat linux.Statx + d.statTo(&stat) + return stat, nil +} + +// StatFSAt implements vfs.FilesystemImpl.StatFSAt. +func (fs *filesystem) StatFSAt(ctx context.Context, rp *vfs.ResolvingPath) (linux.Statfs, error) { + var ds *[]*dentry + fs.renameMu.RLock() + defer fs.renameMuRUnlockAndCheckCaching(&ds) + d, err := fs.resolveLocked(ctx, rp, &ds) + if err != nil { + return linux.Statfs{}, err + } + fsstat, err := d.file.statFS(ctx) + if err != nil { + return linux.Statfs{}, err + } + nameLen := uint64(fsstat.NameLength) + if nameLen > maxFilenameLen { + nameLen = maxFilenameLen + } + return linux.Statfs{ + // This is primarily for distinguishing a gofer file system in + // tests. Testing is important, so instead of defining + // something completely random, use a standard value. + Type: linux.V9FS_MAGIC, + BlockSize: int64(fsstat.BlockSize), + Blocks: fsstat.Blocks, + BlocksFree: fsstat.BlocksFree, + BlocksAvailable: fsstat.BlocksAvailable, + Files: fsstat.Files, + FilesFree: fsstat.FilesFree, + NameLength: nameLen, + }, nil +} + +// SymlinkAt implements vfs.FilesystemImpl.SymlinkAt. +func (fs *filesystem) SymlinkAt(ctx context.Context, rp *vfs.ResolvingPath, target string) error { + return fs.doCreateAt(ctx, rp, false /* dir */, func(parent *dentry, name string) error { + creds := rp.Credentials() + _, err := parent.file.symlink(ctx, target, name, (p9.UID)(creds.EffectiveKUID), (p9.GID)(creds.EffectiveKGID)) + return err + }) +} + +// UnlinkAt implements vfs.FilesystemImpl.UnlinkAt. +func (fs *filesystem) UnlinkAt(ctx context.Context, rp *vfs.ResolvingPath) error { + return fs.unlinkAt(ctx, rp, false /* dir */) +} + +// ListxattrAt implements vfs.FilesystemImpl.ListxattrAt. +func (fs *filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath) ([]string, error) { + var ds *[]*dentry + fs.renameMu.RLock() + defer fs.renameMuRUnlockAndCheckCaching(&ds) + d, err := fs.resolveLocked(ctx, rp, &ds) + if err != nil { + return nil, err + } + return d.listxattr(ctx) +} + +// GetxattrAt implements vfs.FilesystemImpl.GetxattrAt. +func (fs *filesystem) GetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, name string) (string, error) { + var ds *[]*dentry + fs.renameMu.RLock() + defer fs.renameMuRUnlockAndCheckCaching(&ds) + d, err := fs.resolveLocked(ctx, rp, &ds) + if err != nil { + return "", err + } + return d.getxattr(ctx, name) +} + +// SetxattrAt implements vfs.FilesystemImpl.SetxattrAt. +func (fs *filesystem) SetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.SetxattrOptions) error { + var ds *[]*dentry + fs.renameMu.RLock() + defer fs.renameMuRUnlockAndCheckCaching(&ds) + d, err := fs.resolveLocked(ctx, rp, &ds) + if err != nil { + return err + } + return d.setxattr(ctx, &opts) +} + +// RemovexattrAt implements vfs.FilesystemImpl.RemovexattrAt. +func (fs *filesystem) RemovexattrAt(ctx context.Context, rp *vfs.ResolvingPath, name string) error { + var ds *[]*dentry + fs.renameMu.RLock() + defer fs.renameMuRUnlockAndCheckCaching(&ds) + d, err := fs.resolveLocked(ctx, rp, &ds) + if err != nil { + return err + } + return d.removexattr(ctx, name) +} + +// PrependPath implements vfs.FilesystemImpl.PrependPath. +func (fs *filesystem) PrependPath(ctx context.Context, vfsroot, vd vfs.VirtualDentry, b *fspath.Builder) error { + fs.renameMu.RLock() + defer fs.renameMu.RUnlock() + return vfs.GenericPrependPath(vfsroot, vd, b) +} diff --git a/pkg/sentry/fsimpl/gofer/gofer.go b/pkg/sentry/fsimpl/gofer/gofer.go new file mode 100644 index 000000000..d0552bd99 --- /dev/null +++ b/pkg/sentry/fsimpl/gofer/gofer.go @@ -0,0 +1,1147 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// Package gofer provides a filesystem implementation that is backed by a 9p +// server, interchangably referred to as "gofers" throughout this package. +// +// Lock order: +// regularFileFD/directoryFD.mu +// filesystem.renameMu +// dentry.dirMu +// filesystem.syncMu +// dentry.metadataMu +// *** "memmap.Mappable locks" below this point +// dentry.mapsMu +// *** "memmap.Mappable locks taken by Translate" below this point +// dentry.handleMu +// dentry.dataMu +// +// Locking dentry.dirMu in multiple dentries requires holding +// filesystem.renameMu for writing. +package gofer + +import ( + "fmt" + "strconv" + "sync" + "sync/atomic" + "syscall" + + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/log" + "gvisor.dev/gvisor/pkg/p9" + "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" + "gvisor.dev/gvisor/pkg/sentry/kernel/auth" + "gvisor.dev/gvisor/pkg/sentry/memmap" + "gvisor.dev/gvisor/pkg/sentry/pgalloc" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/unet" + "gvisor.dev/gvisor/pkg/usermem" +) + +// FilesystemType implements vfs.FilesystemType. +type FilesystemType struct{} + +// filesystem implements vfs.FilesystemImpl. +type filesystem struct { + vfsfs vfs.Filesystem + + // mfp is used to allocate memory that caches regular file contents. mfp is + // immutable. + mfp pgalloc.MemoryFileProvider + + // Immutable options. + opts filesystemOptions + + // client is the client used by this filesystem. client is immutable. + client *p9.Client + + // uid and gid are the effective KUID and KGID of the filesystem's creator, + // and are used as the owner and group for files that don't specify one. + // uid and gid are immutable. + uid auth.KUID + gid auth.KGID + + // renameMu serves two purposes: + // + // - It synchronizes path resolution with renaming initiated by this + // client. + // + // - It is held by path resolution to ensure that reachable dentries remain + // valid. A dentry is reachable by path resolution if it has a non-zero + // reference count (such that it is usable as vfs.ResolvingPath.Start() or + // is reachable from its children), or if it is a child dentry (such that + // it is reachable from its parent). + renameMu sync.RWMutex + + // cachedDentries contains all dentries with 0 references. (Due to race + // conditions, it may also contain dentries with non-zero references.) + // cachedDentriesLen is the number of dentries in cachedDentries. These + // fields are protected by renameMu. + cachedDentries dentryList + cachedDentriesLen uint64 + + // dentries contains all dentries in this filesystem. specialFileFDs + // contains all open specialFileFDs. These fields are protected by syncMu. + syncMu sync.Mutex + dentries map[*dentry]struct{} + specialFileFDs map[*specialFileFD]struct{} +} + +type filesystemOptions struct { + // "Standard" 9P options. + fd int + aname string + interop InteropMode // derived from the "cache" mount option + msize uint32 + version string + + // maxCachedDentries is the maximum number of dentries with 0 references + // retained by the client. + maxCachedDentries uint64 + + // If forcePageCache is true, host FDs may not be used for application + // memory mappings even if available; instead, the client must perform its + // own caching of regular file pages. This is primarily useful for testing. + forcePageCache bool + + // If limitHostFDTranslation is true, apply maxFillRange() constraints to + // host FD mappings returned by dentry.(memmap.Mappable).Translate(). This + // makes memory accounting behavior more consistent between cases where + // host FDs are / are not available, but may increase the frequency of + // sentry-handled page faults on files for which a host FD is available. + limitHostFDTranslation bool + + // If overlayfsStaleRead is true, O_RDONLY host FDs provided by the remote + // filesystem may not be coherent with writable host FDs opened later, so + // mappings of the former must be replaced by mappings of the latter. This + // is usually only the case when the remote filesystem is an overlayfs + // mount on Linux < 4.19. + overlayfsStaleRead bool + + // If regularFilesUseSpecialFileFD is true, application FDs representing + // regular files will use distinct file handles for each FD, in the same + // way that application FDs representing "special files" such as sockets + // do. Note that this disables client caching and mmap for regular files. + regularFilesUseSpecialFileFD bool +} + +// InteropMode controls the client's interaction with other remote filesystem +// users. +type InteropMode uint32 + +const ( + // InteropModeExclusive is appropriate when the filesystem client is the + // only user of the remote filesystem. + // + // - The client may cache arbitrary filesystem state (file data, metadata, + // filesystem structure, etc.). + // + // - Client changes to filesystem state may be sent to the remote + // filesystem asynchronously, except when server permission checks are + // necessary. + // + // - File timestamps are based on client clocks. This ensures that users of + // the client observe timestamps that are coherent with their own clocks + // and consistent with Linux's semantics. However, since it is not always + // possible for clients to set arbitrary atimes and mtimes, and never + // possible for clients to set arbitrary ctimes, file timestamp changes are + // stored in the client only and never sent to the remote filesystem. + InteropModeExclusive InteropMode = iota + + // InteropModeWritethrough is appropriate when there are read-only users of + // the remote filesystem that expect to observe changes made by the + // filesystem client. + // + // - The client may cache arbitrary filesystem state. + // + // - Client changes to filesystem state must be sent to the remote + // filesystem synchronously. + // + // - File timestamps are based on client clocks. As a corollary, access + // timestamp changes from other remote filesystem users will not be visible + // to the client. + InteropModeWritethrough + + // InteropModeShared is appropriate when there are users of the remote + // filesystem that may mutate its state other than the client. + // + // - The client must verify cached filesystem state before using it. + // + // - Client changes to filesystem state must be sent to the remote + // filesystem synchronously. + // + // - File timestamps are based on server clocks. This is necessary to + // ensure that timestamp changes are synchronized between remote filesystem + // users. + // + // Note that the correctness of InteropModeShared depends on the server + // correctly implementing 9P fids (i.e. each fid immutably represents a + // single filesystem object), even in the presence of remote filesystem + // mutations from other users. If this is violated, the behavior of the + // client is undefined. + InteropModeShared +) + +// GetFilesystem implements vfs.FilesystemType.GetFilesystem. +func (fstype FilesystemType) GetFilesystem(ctx context.Context, vfsObj *vfs.VirtualFilesystem, creds *auth.Credentials, source string, opts vfs.GetFilesystemOptions) (*vfs.Filesystem, *vfs.Dentry, error) { + mfp := pgalloc.MemoryFileProviderFromContext(ctx) + if mfp == nil { + ctx.Warningf("gofer.FilesystemType.GetFilesystem: context does not provide a pgalloc.MemoryFileProvider") + return nil, nil, syserror.EINVAL + } + + mopts := vfs.GenericParseMountOptions(opts.Data) + var fsopts filesystemOptions + + // Check that the transport is "fd". + trans, ok := mopts["trans"] + if !ok { + ctx.Warningf("gofer.FilesystemType.GetFilesystem: transport must be specified as 'trans=fd'") + return nil, nil, syserror.EINVAL + } + delete(mopts, "trans") + if trans != "fd" { + ctx.Warningf("gofer.FilesystemType.GetFilesystem: unsupported transport: trans=%s", trans) + return nil, nil, syserror.EINVAL + } + + // Check that read and write FDs are provided and identical. + rfdstr, ok := mopts["rfdno"] + if !ok { + ctx.Warningf("gofer.FilesystemType.GetFilesystem: read FD must be specified as 'rfdno=") + return nil, nil, syserror.EINVAL + } + delete(mopts, "rfdno") + rfd, err := strconv.Atoi(rfdstr) + if err != nil { + ctx.Warningf("gofer.FilesystemType.GetFilesystem: invalid read FD: rfdno=%s", rfdstr) + return nil, nil, syserror.EINVAL + } + wfdstr, ok := mopts["wfdno"] + if !ok { + ctx.Warningf("gofer.FilesystemType.GetFilesystem: write FD must be specified as 'wfdno=") + return nil, nil, syserror.EINVAL + } + delete(mopts, "wfdno") + wfd, err := strconv.Atoi(wfdstr) + if err != nil { + ctx.Warningf("gofer.FilesystemType.GetFilesystem: invalid write FD: wfdno=%s", wfdstr) + return nil, nil, syserror.EINVAL + } + if rfd != wfd { + ctx.Warningf("gofer.FilesystemType.GetFilesystem: read FD (%d) and write FD (%d) must be equal", rfd, wfd) + return nil, nil, syserror.EINVAL + } + fsopts.fd = rfd + + // Get the attach name. + fsopts.aname = "/" + if aname, ok := mopts["aname"]; ok { + delete(mopts, "aname") + fsopts.aname = aname + } + + // Parse the cache policy. For historical reasons, this defaults to the + // least generally-applicable option, InteropModeExclusive. + fsopts.interop = InteropModeExclusive + if cache, ok := mopts["cache"]; ok { + delete(mopts, "cache") + switch cache { + case "fscache": + fsopts.interop = InteropModeExclusive + case "fscache_writethrough": + fsopts.interop = InteropModeWritethrough + case "none": + fsopts.regularFilesUseSpecialFileFD = true + fallthrough + case "remote_revalidating": + fsopts.interop = InteropModeShared + default: + ctx.Warningf("gofer.FilesystemType.GetFilesystem: invalid cache policy: cache=%s", cache) + return nil, nil, syserror.EINVAL + } + } + + // Parse the 9P message size. + fsopts.msize = 1024 * 1024 // 1M, tested to give good enough performance up to 64M + if msizestr, ok := mopts["msize"]; ok { + delete(mopts, "msize") + msize, err := strconv.ParseUint(msizestr, 10, 32) + if err != nil { + ctx.Warningf("gofer.FilesystemType.GetFilesystem: invalid message size: msize=%s", msizestr) + return nil, nil, syserror.EINVAL + } + fsopts.msize = uint32(msize) + } + + // Parse the 9P protocol version. + fsopts.version = p9.HighestVersionString() + if version, ok := mopts["version"]; ok { + delete(mopts, "version") + fsopts.version = version + } + + // Parse the dentry cache limit. + fsopts.maxCachedDentries = 1000 + if str, ok := mopts["dentry_cache_limit"]; ok { + delete(mopts, "dentry_cache_limit") + maxCachedDentries, err := strconv.ParseUint(str, 10, 64) + if err != nil { + ctx.Warningf("gofer.FilesystemType.GetFilesystem: invalid dentry cache limit: dentry_cache_limit=%s", str) + return nil, nil, syserror.EINVAL + } + fsopts.maxCachedDentries = maxCachedDentries + } + + // Handle simple flags. + if _, ok := mopts["force_page_cache"]; ok { + delete(mopts, "force_page_cache") + fsopts.forcePageCache = true + } + if _, ok := mopts["limit_host_fd_translation"]; ok { + delete(mopts, "limit_host_fd_translation") + fsopts.limitHostFDTranslation = true + } + if _, ok := mopts["overlayfs_stale_read"]; ok { + delete(mopts, "overlayfs_stale_read") + fsopts.overlayfsStaleRead = true + } + // fsopts.regularFilesUseSpecialFileFD can only be enabled by specifying + // "cache=none". + + // Check for unparsed options. + if len(mopts) != 0 { + ctx.Warningf("gofer.FilesystemType.GetFilesystem: unknown options: %v", mopts) + return nil, nil, syserror.EINVAL + } + + // Establish a connection with the server. + conn, err := unet.NewSocket(fsopts.fd) + if err != nil { + return nil, nil, err + } + + // Perform version negotiation with the server. + ctx.UninterruptibleSleepStart(false) + client, err := p9.NewClient(conn, fsopts.msize, fsopts.version) + ctx.UninterruptibleSleepFinish(false) + if err != nil { + conn.Close() + return nil, nil, err + } + // Ownership of conn has been transferred to client. + + // Perform attach to obtain the filesystem root. + ctx.UninterruptibleSleepStart(false) + attached, err := client.Attach(fsopts.aname) + ctx.UninterruptibleSleepFinish(false) + if err != nil { + client.Close() + return nil, nil, err + } + attachFile := p9file{attached} + qid, attrMask, attr, err := attachFile.getAttr(ctx, dentryAttrMask()) + if err != nil { + attachFile.close(ctx) + client.Close() + return nil, nil, err + } + + // Construct the filesystem object. + fs := &filesystem{ + mfp: mfp, + opts: fsopts, + uid: creds.EffectiveKUID, + gid: creds.EffectiveKGID, + client: client, + dentries: make(map[*dentry]struct{}), + specialFileFDs: make(map[*specialFileFD]struct{}), + } + fs.vfsfs.Init(vfsObj, fs) + + // Construct the root dentry. + root, err := fs.newDentry(ctx, attachFile, qid, attrMask, &attr) + if err != nil { + attachFile.close(ctx) + fs.vfsfs.DecRef() + return nil, nil, err + } + // Set the root's reference count to 2. One reference is returned to the + // caller, and the other is deliberately leaked to prevent the root from + // being "cached" and subsequently evicted. Its resources will still be + // cleaned up by fs.Release(). + root.refs = 2 + + return &fs.vfsfs, &root.vfsd, nil +} + +// Release implements vfs.FilesystemImpl.Release. +func (fs *filesystem) Release() { + ctx := context.Background() + mf := fs.mfp.MemoryFile() + + fs.syncMu.Lock() + for d := range fs.dentries { + d.handleMu.Lock() + d.dataMu.Lock() + if d.handleWritable { + // Write dirty cached data to the remote file. + if err := fsutil.SyncDirtyAll(ctx, &d.cache, &d.dirty, d.size, fs.mfp.MemoryFile(), d.handle.writeFromBlocksAt); err != nil { + log.Warningf("gofer.filesystem.Release: failed to flush dentry: %v", err) + } + // TODO(jamieliu): Do we need to flushf/fsync d? + } + // Discard cached pages. + d.cache.DropAll(mf) + d.dirty.RemoveAll() + d.dataMu.Unlock() + // Close the host fd if one exists. + if d.handle.fd >= 0 { + syscall.Close(int(d.handle.fd)) + d.handle.fd = -1 + } + d.handleMu.Unlock() + } + // There can't be any specialFileFDs still using fs, since each such + // FileDescription would hold a reference on a Mount holding a reference on + // fs. + fs.syncMu.Unlock() + + // Close the connection to the server. This implicitly clunks all fids. + fs.client.Close() +} + +// dentry implements vfs.DentryImpl. +type dentry struct { + vfsd vfs.Dentry + + // refs is the reference count. Each dentry holds a reference on its + // parent, even if disowned. refs is accessed using atomic memory + // operations. + refs int64 + + // fs is the owning filesystem. fs is immutable. + fs *filesystem + + // We don't support hard links, so each dentry maps 1:1 to an inode. + + // file is the unopened p9.File that backs this dentry. file is immutable. + file p9file + + // If deleted is non-zero, the file represented by this dentry has been + // deleted. deleted is accessed using atomic memory operations. + deleted uint32 + + // If cached is true, dentryEntry links dentry into + // filesystem.cachedDentries. cached and dentryEntry are protected by + // filesystem.renameMu. + cached bool + dentryEntry + + dirMu sync.Mutex + + // If this dentry represents a directory, and InteropModeShared is not in + // effect, negativeChildren is a set of child names in this directory that + // are known not to exist. negativeChildren is protected by dirMu. + negativeChildren map[string]struct{} + + // If this dentry represents a directory, InteropModeShared is not in + // effect, and dirents is not nil, it is a cache of all entries in the + // directory, in the order they were returned by the server. dirents is + // protected by dirMu. + dirents []vfs.Dirent + + // Cached metadata; protected by metadataMu and accessed using atomic + // memory operations unless otherwise specified. + metadataMu sync.Mutex + ino uint64 // immutable + mode uint32 // type is immutable, perms are mutable + uid uint32 // auth.KUID, but stored as raw uint32 for sync/atomic + gid uint32 // auth.KGID, but ... + blockSize uint32 // 0 if unknown + // Timestamps, all nsecs from the Unix epoch. + atime int64 + mtime int64 + ctime int64 + btime int64 + // File size, protected by both metadataMu and dataMu (i.e. both must be + // locked to mutate it). + size uint64 + + mapsMu sync.Mutex + + // If this dentry represents a regular file, mappings tracks mappings of + // the file into memmap.MappingSpaces. mappings is protected by mapsMu. + mappings memmap.MappingSet + + // If this dentry represents a regular file or directory: + // + // - handle is the I/O handle used by all regularFileFDs/directoryFDs + // representing this dentry. + // + // - handleReadable is true if handle is readable. + // + // - handleWritable is true if handle is writable. + // + // Invariants: + // + // - If handleReadable == handleWritable == false, then handle.file == nil + // (i.e. there is no open handle). Conversely, if handleReadable || + // handleWritable == true, then handle.file != nil (i.e. there is an open + // handle). + // + // - handleReadable and handleWritable cannot transition from true to false + // (i.e. handles may not be downgraded). + // + // These fields are protected by handleMu. + handleMu sync.RWMutex + handle handle + handleReadable bool + handleWritable bool + + dataMu sync.RWMutex + + // If this dentry represents a regular file that is client-cached, cache + // maps offsets into the cached file to offsets into + // filesystem.mfp.MemoryFile() that store the file's data. cache is + // protected by dataMu. + cache fsutil.FileRangeSet + + // If this dentry represents a regular file that is client-cached, dirty + // tracks dirty segments in cache. dirty is protected by dataMu. + dirty fsutil.DirtySet + + // pf implements platform.File for mappings of handle.fd. + pf dentryPlatformFile + + // If this dentry represents a symbolic link, InteropModeShared is not in + // effect, and haveTarget is true, target is the symlink target. haveTarget + // and target are protected by dataMu. + haveTarget bool + target string +} + +// dentryAttrMask returns a p9.AttrMask enabling all attributes used by the +// gofer client. +func dentryAttrMask() p9.AttrMask { + return p9.AttrMask{ + Mode: true, + UID: true, + GID: true, + ATime: true, + MTime: true, + CTime: true, + Size: true, + BTime: true, + } +} + +// newDentry creates a new dentry representing the given file. The dentry +// initially has no references, but is not cached; it is the caller's +// responsibility to set the dentry's reference count and/or call +// dentry.checkCachingLocked() as appropriate. +func (fs *filesystem) newDentry(ctx context.Context, file p9file, qid p9.QID, mask p9.AttrMask, attr *p9.Attr) (*dentry, error) { + if !mask.Mode { + ctx.Warningf("can't create gofer.dentry without file type") + return nil, syserror.EIO + } + if attr.Mode.FileType() == p9.ModeRegular && !mask.Size { + ctx.Warningf("can't create regular file gofer.dentry without file size") + return nil, syserror.EIO + } + + d := &dentry{ + fs: fs, + file: file, + ino: qid.Path, + mode: uint32(attr.Mode), + uid: uint32(fs.uid), + gid: uint32(fs.gid), + blockSize: usermem.PageSize, + handle: handle{ + fd: -1, + }, + } + d.pf.dentry = d + if mask.UID { + d.uid = uint32(attr.UID) + } + if mask.GID { + d.gid = uint32(attr.GID) + } + if mask.Size { + d.size = attr.Size + } + if attr.BlockSize != 0 { + d.blockSize = uint32(attr.BlockSize) + } + if mask.ATime { + d.atime = dentryTimestampFromP9(attr.ATimeSeconds, attr.ATimeNanoSeconds) + } + if mask.MTime { + d.mtime = dentryTimestampFromP9(attr.MTimeSeconds, attr.MTimeNanoSeconds) + } + if mask.CTime { + d.ctime = dentryTimestampFromP9(attr.CTimeSeconds, attr.CTimeNanoSeconds) + } + if mask.BTime { + d.btime = dentryTimestampFromP9(attr.BTimeSeconds, attr.BTimeNanoSeconds) + } + d.vfsd.Init(d) + + fs.syncMu.Lock() + fs.dentries[d] = struct{}{} + fs.syncMu.Unlock() + return d, nil +} + +// updateFromP9Attrs is called to update d's metadata after an update from the +// remote filesystem. +func (d *dentry) updateFromP9Attrs(mask p9.AttrMask, attr *p9.Attr) { + d.metadataMu.Lock() + if mask.Mode { + if got, want := uint32(attr.Mode.FileType()), d.fileType(); got != want { + d.metadataMu.Unlock() + panic(fmt.Sprintf("gofer.dentry file type changed from %#o to %#o", want, got)) + } + atomic.StoreUint32(&d.mode, uint32(attr.Mode)) + } + if mask.UID { + atomic.StoreUint32(&d.uid, uint32(attr.UID)) + } + if mask.GID { + atomic.StoreUint32(&d.gid, uint32(attr.GID)) + } + // There is no P9_GETATTR_* bit for I/O block size. + if attr.BlockSize != 0 { + atomic.StoreUint32(&d.blockSize, uint32(attr.BlockSize)) + } + if mask.ATime { + atomic.StoreInt64(&d.atime, dentryTimestampFromP9(attr.ATimeSeconds, attr.ATimeNanoSeconds)) + } + if mask.MTime { + atomic.StoreInt64(&d.mtime, dentryTimestampFromP9(attr.MTimeSeconds, attr.MTimeNanoSeconds)) + } + if mask.CTime { + atomic.StoreInt64(&d.ctime, dentryTimestampFromP9(attr.CTimeSeconds, attr.CTimeNanoSeconds)) + } + if mask.BTime { + atomic.StoreInt64(&d.btime, dentryTimestampFromP9(attr.BTimeSeconds, attr.BTimeNanoSeconds)) + } + if mask.Size { + d.dataMu.Lock() + atomic.StoreUint64(&d.size, attr.Size) + d.dataMu.Unlock() + } + d.metadataMu.Unlock() +} + +func (d *dentry) updateFromGetattr(ctx context.Context) error { + // Use d.handle.file, which represents a 9P fid that has been opened, in + // preference to d.file, which represents a 9P fid that has not. This may + // be significantly more efficient in some implementations. + var ( + file p9file + handleMuRLocked bool + ) + d.handleMu.RLock() + if !d.handle.file.isNil() { + file = d.handle.file + handleMuRLocked = true + } else { + file = d.file + d.handleMu.RUnlock() + } + _, attrMask, attr, err := file.getAttr(ctx, dentryAttrMask()) + if handleMuRLocked { + d.handleMu.RUnlock() + } + if err != nil { + return err + } + d.updateFromP9Attrs(attrMask, &attr) + return nil +} + +func (d *dentry) fileType() uint32 { + return atomic.LoadUint32(&d.mode) & linux.S_IFMT +} + +func (d *dentry) statTo(stat *linux.Statx) { + stat.Mask = linux.STATX_TYPE | linux.STATX_MODE | linux.STATX_NLINK | linux.STATX_UID | linux.STATX_GID | linux.STATX_ATIME | linux.STATX_MTIME | linux.STATX_CTIME | linux.STATX_INO | linux.STATX_SIZE | linux.STATX_BLOCKS | linux.STATX_BTIME + stat.Blksize = atomic.LoadUint32(&d.blockSize) + stat.Nlink = 1 + if d.isDir() { + stat.Nlink = 2 + } + stat.UID = atomic.LoadUint32(&d.uid) + stat.GID = atomic.LoadUint32(&d.gid) + stat.Mode = uint16(atomic.LoadUint32(&d.mode)) + stat.Ino = d.ino + stat.Size = atomic.LoadUint64(&d.size) + // This is consistent with regularFileFD.Seek(), which treats regular files + // as having no holes. + stat.Blocks = (stat.Size + 511) / 512 + stat.Atime = statxTimestampFromDentry(atomic.LoadInt64(&d.atime)) + stat.Btime = statxTimestampFromDentry(atomic.LoadInt64(&d.btime)) + stat.Ctime = statxTimestampFromDentry(atomic.LoadInt64(&d.ctime)) + stat.Mtime = statxTimestampFromDentry(atomic.LoadInt64(&d.mtime)) + // TODO(jamieliu): device number +} + +func (d *dentry) setStat(ctx context.Context, creds *auth.Credentials, stat *linux.Statx, mnt *vfs.Mount) error { + if stat.Mask == 0 { + return nil + } + if stat.Mask&^(linux.STATX_MODE|linux.STATX_UID|linux.STATX_GID|linux.STATX_ATIME|linux.STATX_MTIME|linux.STATX_SIZE) != 0 { + return syserror.EPERM + } + if err := vfs.CheckSetStat(creds, stat, uint16(atomic.LoadUint32(&d.mode))&^linux.S_IFMT, auth.KUID(atomic.LoadUint32(&d.uid)), auth.KGID(atomic.LoadUint32(&d.gid))); err != nil { + return err + } + if err := mnt.CheckBeginWrite(); err != nil { + return err + } + defer mnt.EndWrite() + setLocalAtime := false + setLocalMtime := false + if d.fs.opts.interop != InteropModeShared { + // Timestamp updates will be handled locally. + setLocalAtime = stat.Mask&linux.STATX_ATIME != 0 + setLocalMtime = stat.Mask&linux.STATX_MTIME != 0 + stat.Mask &^= linux.STATX_ATIME | linux.STATX_MTIME + if !setLocalMtime && (stat.Mask&linux.STATX_SIZE != 0) { + // Truncate updates mtime. + setLocalMtime = true + stat.Mtime.Nsec = linux.UTIME_NOW + } + } + d.metadataMu.Lock() + defer d.metadataMu.Unlock() + if stat.Mask != 0 { + if err := d.file.setAttr(ctx, p9.SetAttrMask{ + Permissions: stat.Mask&linux.STATX_MODE != 0, + UID: stat.Mask&linux.STATX_UID != 0, + GID: stat.Mask&linux.STATX_GID != 0, + Size: stat.Mask&linux.STATX_SIZE != 0, + ATime: stat.Mask&linux.STATX_ATIME != 0, + MTime: stat.Mask&linux.STATX_MTIME != 0, + ATimeNotSystemTime: stat.Atime.Nsec != linux.UTIME_NOW, + MTimeNotSystemTime: stat.Mtime.Nsec != linux.UTIME_NOW, + }, p9.SetAttr{ + Permissions: p9.FileMode(stat.Mode), + UID: p9.UID(stat.UID), + GID: p9.GID(stat.GID), + Size: stat.Size, + ATimeSeconds: uint64(stat.Atime.Sec), + ATimeNanoSeconds: uint64(stat.Atime.Nsec), + MTimeSeconds: uint64(stat.Mtime.Sec), + MTimeNanoSeconds: uint64(stat.Mtime.Nsec), + }); err != nil { + return err + } + } + if d.fs.opts.interop == InteropModeShared { + // There's no point to updating d's metadata in this case since it'll + // be overwritten by revalidation before the next time it's used + // anyway. (InteropModeShared inhibits client caching of regular file + // data, so there's no cache to truncate either.) + return nil + } + now, haveNow := nowFromContext(ctx) + if !haveNow { + ctx.Warningf("gofer.dentry.setStat: current time not available") + } + if stat.Mask&linux.STATX_MODE != 0 { + atomic.StoreUint32(&d.mode, d.fileType()|uint32(stat.Mode)) + } + if stat.Mask&linux.STATX_UID != 0 { + atomic.StoreUint32(&d.uid, stat.UID) + } + if stat.Mask&linux.STATX_GID != 0 { + atomic.StoreUint32(&d.gid, stat.GID) + } + if setLocalAtime { + if stat.Atime.Nsec == linux.UTIME_NOW { + if haveNow { + atomic.StoreInt64(&d.atime, now) + } + } else { + atomic.StoreInt64(&d.atime, dentryTimestampFromStatx(stat.Atime)) + } + } + if setLocalMtime { + if stat.Mtime.Nsec == linux.UTIME_NOW { + if haveNow { + atomic.StoreInt64(&d.mtime, now) + } + } else { + atomic.StoreInt64(&d.mtime, dentryTimestampFromStatx(stat.Mtime)) + } + } + if haveNow { + atomic.StoreInt64(&d.ctime, now) + } + if stat.Mask&linux.STATX_SIZE != 0 { + d.dataMu.Lock() + oldSize := d.size + d.size = stat.Size + // d.dataMu must be unlocked to lock d.mapsMu and invalidate mappings + // below. This allows concurrent calls to Read/Translate/etc. These + // functions synchronize with truncation by refusing to use cache + // contents beyond the new d.size. (We are still holding d.metadataMu, + // so we can't race with Write or another truncate.) + d.dataMu.Unlock() + if d.size < oldSize { + oldpgend := pageRoundUp(oldSize) + newpgend := pageRoundUp(d.size) + if oldpgend != newpgend { + d.mapsMu.Lock() + d.mappings.Invalidate(memmap.MappableRange{newpgend, oldpgend}, memmap.InvalidateOpts{ + // Compare Linux's mm/truncate.c:truncate_setsize() => + // truncate_pagecache() => + // mm/memory.c:unmap_mapping_range(evencows=1). + InvalidatePrivate: true, + }) + d.mapsMu.Unlock() + } + // We are now guaranteed that there are no translations of + // truncated pages, and can remove them from the cache. Since + // truncated pages have been removed from the remote file, they + // should be dropped without being written back. + d.dataMu.Lock() + d.cache.Truncate(d.size, d.fs.mfp.MemoryFile()) + d.dirty.KeepClean(memmap.MappableRange{d.size, oldpgend}) + d.dataMu.Unlock() + } + } + return nil +} + +func (d *dentry) checkPermissions(creds *auth.Credentials, ats vfs.AccessTypes, isDir bool) error { + return vfs.GenericCheckPermissions(creds, ats, isDir, uint16(atomic.LoadUint32(&d.mode))&0777, auth.KUID(atomic.LoadUint32(&d.uid)), auth.KGID(atomic.LoadUint32(&d.gid))) +} + +// IncRef implements vfs.DentryImpl.IncRef. +func (d *dentry) IncRef() { + // d.refs may be 0 if d.fs.renameMu is locked, which serializes against + // d.checkCachingLocked(). + atomic.AddInt64(&d.refs, 1) +} + +// TryIncRef implements vfs.DentryImpl.TryIncRef. +func (d *dentry) TryIncRef() bool { + for { + refs := atomic.LoadInt64(&d.refs) + if refs == 0 { + return false + } + if atomic.CompareAndSwapInt64(&d.refs, refs, refs+1) { + return true + } + } +} + +// DecRef implements vfs.DentryImpl.DecRef. +func (d *dentry) DecRef() { + if refs := atomic.AddInt64(&d.refs, -1); refs == 0 { + d.fs.renameMu.Lock() + d.checkCachingLocked() + d.fs.renameMu.Unlock() + } else if refs < 0 { + panic("gofer.dentry.DecRef() called without holding a reference") + } +} + +// checkCachingLocked should be called after d's reference count becomes 0 or it +// becomes disowned. +// +// Preconditions: d.fs.renameMu must be locked for writing. +func (d *dentry) checkCachingLocked() { + // Dentries with a non-zero reference count must be retained. (The only way + // to obtain a reference on a dentry with zero references is via path + // resolution, which requires renameMu, so if d.refs is zero then it will + // remain zero while we hold renameMu for writing.) + if atomic.LoadInt64(&d.refs) != 0 { + if d.cached { + d.fs.cachedDentries.Remove(d) + d.fs.cachedDentriesLen-- + d.cached = false + } + return + } + // Non-child dentries with zero references are no longer reachable by path + // resolution and should be dropped immediately. + if d.vfsd.Parent() == nil || d.vfsd.IsDisowned() { + if d.cached { + d.fs.cachedDentries.Remove(d) + d.fs.cachedDentriesLen-- + d.cached = false + } + d.destroyLocked() + return + } + // If d is already cached, just move it to the front of the LRU. + if d.cached { + d.fs.cachedDentries.Remove(d) + d.fs.cachedDentries.PushFront(d) + return + } + // Cache the dentry, then evict the least recently used cached dentry if + // the cache becomes over-full. + d.fs.cachedDentries.PushFront(d) + d.fs.cachedDentriesLen++ + d.cached = true + if d.fs.cachedDentriesLen > d.fs.opts.maxCachedDentries { + victim := d.fs.cachedDentries.Back() + d.fs.cachedDentries.Remove(victim) + d.fs.cachedDentriesLen-- + victim.cached = false + // victim.refs may have become non-zero from an earlier path + // resolution since it was inserted into fs.cachedDentries; see + // dentry.incRefLocked(). Either way, we brought + // fs.cachedDentriesLen back down to fs.opts.maxCachedDentries, so + // we don't loop. + if atomic.LoadInt64(&victim.refs) == 0 { + if victimParentVFSD := victim.vfsd.Parent(); victimParentVFSD != nil { + victimParent := victimParentVFSD.Impl().(*dentry) + victimParent.dirMu.Lock() + if !victim.vfsd.IsDisowned() { + // victim can't be a mount point (in any mount + // namespace), since VFS holds references on mount + // points. + d.fs.vfsfs.VirtualFilesystem().ForceDeleteDentry(&victim.vfsd) + // We're only deleting the dentry, not the file it + // represents, so we don't need to update + // victimParent.dirents etc. + } + victimParent.dirMu.Unlock() + } + victim.destroyLocked() + } + } +} + +// Preconditions: d.fs.renameMu must be locked for writing. d.refs == 0. d is +// not a child dentry. +func (d *dentry) destroyLocked() { + ctx := context.Background() + d.handleMu.Lock() + if !d.handle.file.isNil() { + mf := d.fs.mfp.MemoryFile() + d.dataMu.Lock() + // Write dirty pages back to the remote filesystem. + if d.handleWritable { + if err := fsutil.SyncDirtyAll(ctx, &d.cache, &d.dirty, d.size, mf, d.handle.writeFromBlocksAt); err != nil { + log.Warningf("gofer.dentry.DecRef: failed to write dirty data back: %v", err) + } + } + // Discard cached data. + d.cache.DropAll(mf) + d.dirty.RemoveAll() + d.dataMu.Unlock() + // Clunk open fids and close open host FDs. + d.handle.close(ctx) + } + d.handleMu.Unlock() + d.file.close(ctx) + // Remove d from the set of all dentries. + d.fs.syncMu.Lock() + delete(d.fs.dentries, d) + d.fs.syncMu.Unlock() + // Drop the reference held by d on its parent. + if parentVFSD := d.vfsd.Parent(); parentVFSD != nil { + parent := parentVFSD.Impl().(*dentry) + // This is parent.DecRef() without recursive locking of d.fs.renameMu. + if refs := atomic.AddInt64(&parent.refs, -1); refs == 0 { + parent.checkCachingLocked() + } else if refs < 0 { + panic("gofer.dentry.DecRef() called without holding a reference") + } + } +} + +func (d *dentry) isDeleted() bool { + return atomic.LoadUint32(&d.deleted) != 0 +} + +func (d *dentry) setDeleted() { + atomic.StoreUint32(&d.deleted, 1) +} + +func (d *dentry) listxattr(ctx context.Context) ([]string, error) { + return nil, syserror.ENOTSUP +} + +func (d *dentry) getxattr(ctx context.Context, name string) (string, error) { + // TODO(jamieliu): add vfs.GetxattrOptions.Size + return d.file.getXattr(ctx, name, linux.XATTR_SIZE_MAX) +} + +func (d *dentry) setxattr(ctx context.Context, opts *vfs.SetxattrOptions) error { + return d.file.setXattr(ctx, opts.Name, opts.Value, opts.Flags) +} + +func (d *dentry) removexattr(ctx context.Context, name string) error { + return syserror.ENOTSUP +} + +// Preconditions: d.isRegularFile() || d.isDirectory(). +func (d *dentry) ensureSharedHandle(ctx context.Context, read, write, trunc bool) error { + // O_TRUNC unconditionally requires us to obtain a new handle (opened with + // O_TRUNC). + if !trunc { + d.handleMu.RLock() + if (!read || d.handleReadable) && (!write || d.handleWritable) { + // The current handle is sufficient. + d.handleMu.RUnlock() + return nil + } + d.handleMu.RUnlock() + } + + haveOldFD := false + d.handleMu.Lock() + if (read && !d.handleReadable) || (write && !d.handleWritable) || trunc { + // Get a new handle. + wantReadable := d.handleReadable || read + wantWritable := d.handleWritable || write + h, err := openHandle(ctx, d.file, wantReadable, wantWritable, trunc) + if err != nil { + d.handleMu.Unlock() + return err + } + if !d.handle.file.isNil() { + // Check that old and new handles are compatible: If the old handle + // includes a host file descriptor but the new one does not, or + // vice versa, old and new memory mappings may be incoherent. + haveOldFD = d.handle.fd >= 0 + haveNewFD := h.fd >= 0 + if haveOldFD != haveNewFD { + d.handleMu.Unlock() + ctx.Warningf("gofer.dentry.ensureSharedHandle: can't change host FD availability from %v to %v across dentry handle upgrade", haveOldFD, haveNewFD) + h.close(ctx) + return syserror.EIO + } + if haveOldFD { + // We may have raced with callers of d.pf.FD() that are now + // using the old file descriptor, preventing us from safely + // closing it. We could handle this by invalidating existing + // memmap.Translations, but this is expensive. Instead, use + // dup2() to make the old file descriptor refer to the new file + // description, then close the new file descriptor (which is no + // longer needed). Racing callers may use the old or new file + // description, but this doesn't matter since they refer to the + // same file (unless d.fs.opts.overlayfsStaleRead is true, + // which we handle separately). + if err := syscall.Dup2(int(h.fd), int(d.handle.fd)); err != nil { + d.handleMu.Unlock() + ctx.Warningf("gofer.dentry.ensureSharedHandle: failed to dup fd %d to fd %d: %v", h.fd, d.handle.fd, err) + h.close(ctx) + return err + } + syscall.Close(int(h.fd)) + h.fd = d.handle.fd + if d.fs.opts.overlayfsStaleRead { + // Replace sentry mappings of the old FD with mappings of + // the new FD, since the two are not necessarily coherent. + if err := d.pf.hostFileMapper.RegenerateMappings(int(h.fd)); err != nil { + d.handleMu.Unlock() + ctx.Warningf("gofer.dentry.ensureSharedHandle: failed to replace sentry mappings of old FD with mappings of new FD: %v", err) + h.close(ctx) + return err + } + } + // Clunk the old fid before making the new handle visible (by + // unlocking d.handleMu). + d.handle.file.close(ctx) + } + } + // Switch to the new handle. + d.handle = h + d.handleReadable = wantReadable + d.handleWritable = wantWritable + } + d.handleMu.Unlock() + + if d.fs.opts.overlayfsStaleRead && haveOldFD { + // Invalidate application mappings that may be using the old FD; they + // will be replaced with mappings using the new FD after future calls + // to d.Translate(). This requires holding d.mapsMu, which precedes + // d.handleMu in the lock order. + d.mapsMu.Lock() + d.mappings.InvalidateAll(memmap.InvalidateOpts{}) + d.mapsMu.Unlock() + } + + return nil +} + +// fileDescription is embedded by gofer implementations of +// vfs.FileDescriptionImpl. +type fileDescription struct { + vfsfd vfs.FileDescription + vfs.FileDescriptionDefaultImpl +} + +func (fd *fileDescription) filesystem() *filesystem { + return fd.vfsfd.Mount().Filesystem().Impl().(*filesystem) +} + +func (fd *fileDescription) dentry() *dentry { + return fd.vfsfd.Dentry().Impl().(*dentry) +} + +// Stat implements vfs.FileDescriptionImpl.Stat. +func (fd *fileDescription) Stat(ctx context.Context, opts vfs.StatOptions) (linux.Statx, error) { + d := fd.dentry() + if d.fs.opts.interop == InteropModeShared && opts.Mask&(linux.STATX_MODE|linux.STATX_UID|linux.STATX_GID|linux.STATX_ATIME|linux.STATX_MTIME|linux.STATX_CTIME|linux.STATX_SIZE|linux.STATX_BLOCKS|linux.STATX_BTIME) != 0 && opts.Sync != linux.AT_STATX_DONT_SYNC { + // TODO(jamieliu): Use specialFileFD.handle.file for the getattr if + // available? + if err := d.updateFromGetattr(ctx); err != nil { + return linux.Statx{}, err + } + } + var stat linux.Statx + d.statTo(&stat) + return stat, nil +} + +// SetStat implements vfs.FileDescriptionImpl.SetStat. +func (fd *fileDescription) SetStat(ctx context.Context, opts vfs.SetStatOptions) error { + return fd.dentry().setStat(ctx, auth.CredentialsFromContext(ctx), &opts.Stat, fd.vfsfd.Mount()) +} + +// Listxattr implements vfs.FileDescriptionImpl.Listxattr. +func (fd *fileDescription) Listxattr(ctx context.Context) ([]string, error) { + return fd.dentry().listxattr(ctx) +} + +// Getxattr implements vfs.FileDescriptionImpl.Getxattr. +func (fd *fileDescription) Getxattr(ctx context.Context, name string) (string, error) { + return fd.dentry().getxattr(ctx, name) +} + +// Setxattr implements vfs.FileDescriptionImpl.Setxattr. +func (fd *fileDescription) Setxattr(ctx context.Context, opts vfs.SetxattrOptions) error { + return fd.dentry().setxattr(ctx, &opts) +} + +// Removexattr implements vfs.FileDescriptionImpl.Removexattr. +func (fd *fileDescription) Removexattr(ctx context.Context, name string) error { + return fd.dentry().removexattr(ctx, name) +} diff --git a/pkg/sentry/fsimpl/gofer/handle.go b/pkg/sentry/fsimpl/gofer/handle.go new file mode 100644 index 000000000..cfe66f797 --- /dev/null +++ b/pkg/sentry/fsimpl/gofer/handle.go @@ -0,0 +1,135 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package gofer + +import ( + "syscall" + + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/p9" + "gvisor.dev/gvisor/pkg/safemem" +) + +// handle represents a remote "open file descriptor", consisting of an opened +// fid (p9.File) and optionally a host file descriptor. +type handle struct { + file p9file + fd int32 // -1 if unavailable +} + +// Preconditions: read || write. +func openHandle(ctx context.Context, file p9file, read, write, trunc bool) (handle, error) { + _, newfile, err := file.walk(ctx, nil) + if err != nil { + return handle{fd: -1}, err + } + var flags p9.OpenFlags + switch { + case read && !write: + flags = p9.ReadOnly + case !read && write: + flags = p9.WriteOnly + case read && write: + flags = p9.ReadWrite + } + if trunc { + flags |= p9.OpenTruncate + } + fdobj, _, _, err := newfile.open(ctx, flags) + if err != nil { + newfile.close(ctx) + return handle{fd: -1}, err + } + fd := int32(-1) + if fdobj != nil { + fd = int32(fdobj.Release()) + } + return handle{ + file: newfile, + fd: fd, + }, nil +} + +func (h *handle) close(ctx context.Context) { + h.file.close(ctx) + h.file = p9file{} + if h.fd >= 0 { + syscall.Close(int(h.fd)) + h.fd = -1 + } +} + +func (h *handle) readToBlocksAt(ctx context.Context, dsts safemem.BlockSeq, offset uint64) (uint64, error) { + if dsts.IsEmpty() { + return 0, nil + } + if h.fd >= 0 { + ctx.UninterruptibleSleepStart(false) + n, err := hostPreadv(h.fd, dsts, int64(offset)) + ctx.UninterruptibleSleepFinish(false) + return n, err + } + if dsts.NumBlocks() == 1 && !dsts.Head().NeedSafecopy() { + n, err := h.file.readAt(ctx, dsts.Head().ToSlice(), offset) + return uint64(n), err + } + // Buffer the read since p9.File.ReadAt() takes []byte. + buf := make([]byte, dsts.NumBytes()) + n, err := h.file.readAt(ctx, buf, offset) + if n == 0 { + return 0, err + } + if cp, cperr := safemem.CopySeq(dsts, safemem.BlockSeqOf(safemem.BlockFromSafeSlice(buf[:n]))); cperr != nil { + return cp, cperr + } + return uint64(n), err +} + +func (h *handle) writeFromBlocksAt(ctx context.Context, srcs safemem.BlockSeq, offset uint64) (uint64, error) { + if srcs.IsEmpty() { + return 0, nil + } + if h.fd >= 0 { + ctx.UninterruptibleSleepStart(false) + n, err := hostPwritev(h.fd, srcs, int64(offset)) + ctx.UninterruptibleSleepFinish(false) + return n, err + } + if srcs.NumBlocks() == 1 && !srcs.Head().NeedSafecopy() { + n, err := h.file.writeAt(ctx, srcs.Head().ToSlice(), offset) + return uint64(n), err + } + // Buffer the write since p9.File.WriteAt() takes []byte. + buf := make([]byte, srcs.NumBytes()) + cp, cperr := safemem.CopySeq(safemem.BlockSeqOf(safemem.BlockFromSafeSlice(buf)), srcs) + if cp == 0 { + return 0, cperr + } + n, err := h.file.writeAt(ctx, buf[:cp], offset) + if err != nil { + return uint64(n), err + } + return cp, cperr +} + +func (h *handle) sync(ctx context.Context) error { + if h.fd >= 0 { + ctx.UninterruptibleSleepStart(false) + err := syscall.Fsync(int(h.fd)) + ctx.UninterruptibleSleepFinish(false) + return err + } + return h.file.fsync(ctx) +} diff --git a/pkg/sentry/fsimpl/gofer/handle_unsafe.go b/pkg/sentry/fsimpl/gofer/handle_unsafe.go new file mode 100644 index 000000000..19560ab26 --- /dev/null +++ b/pkg/sentry/fsimpl/gofer/handle_unsafe.go @@ -0,0 +1,66 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package gofer + +import ( + "syscall" + "unsafe" + + "gvisor.dev/gvisor/pkg/safemem" +) + +// Preconditions: !dsts.IsEmpty(). +func hostPreadv(fd int32, dsts safemem.BlockSeq, off int64) (uint64, error) { + // No buffering is necessary regardless of safecopy; host syscalls will + // return EFAULT if appropriate, instead of raising SIGBUS. + if dsts.NumBlocks() == 1 { + // Use pread() instead of preadv() to avoid iovec allocation and + // copying. + dst := dsts.Head() + n, _, e := syscall.Syscall6(syscall.SYS_PREAD64, uintptr(fd), dst.Addr(), uintptr(dst.Len()), uintptr(off), 0, 0) + if e != 0 { + return 0, e + } + return uint64(n), nil + } + iovs := safemem.IovecsFromBlockSeq(dsts) + n, _, e := syscall.Syscall6(syscall.SYS_PREADV, uintptr(fd), uintptr((unsafe.Pointer)(&iovs[0])), uintptr(len(iovs)), uintptr(off), 0, 0) + if e != 0 { + return 0, e + } + return uint64(n), nil +} + +// Preconditions: !srcs.IsEmpty(). +func hostPwritev(fd int32, srcs safemem.BlockSeq, off int64) (uint64, error) { + // No buffering is necessary regardless of safecopy; host syscalls will + // return EFAULT if appropriate, instead of raising SIGBUS. + if srcs.NumBlocks() == 1 { + // Use pwrite() instead of pwritev() to avoid iovec allocation and + // copying. + src := srcs.Head() + n, _, e := syscall.Syscall6(syscall.SYS_PWRITE64, uintptr(fd), src.Addr(), uintptr(src.Len()), uintptr(off), 0, 0) + if e != 0 { + return 0, e + } + return uint64(n), nil + } + iovs := safemem.IovecsFromBlockSeq(srcs) + n, _, e := syscall.Syscall6(syscall.SYS_PWRITEV, uintptr(fd), uintptr((unsafe.Pointer)(&iovs[0])), uintptr(len(iovs)), uintptr(off), 0, 0) + if e != 0 { + return 0, e + } + return uint64(n), nil +} diff --git a/pkg/sentry/fsimpl/gofer/p9file.go b/pkg/sentry/fsimpl/gofer/p9file.go new file mode 100644 index 000000000..755ac2985 --- /dev/null +++ b/pkg/sentry/fsimpl/gofer/p9file.go @@ -0,0 +1,219 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package gofer + +import ( + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/fd" + "gvisor.dev/gvisor/pkg/p9" + "gvisor.dev/gvisor/pkg/syserror" +) + +// p9file is a wrapper around p9.File that provides methods that are +// Context-aware. +type p9file struct { + file p9.File +} + +func (f p9file) isNil() bool { + return f.file == nil +} + +func (f p9file) walk(ctx context.Context, names []string) ([]p9.QID, p9file, error) { + ctx.UninterruptibleSleepStart(false) + qids, newfile, err := f.file.Walk(names) + ctx.UninterruptibleSleepFinish(false) + return qids, p9file{newfile}, err +} + +func (f p9file) walkGetAttr(ctx context.Context, names []string) ([]p9.QID, p9file, p9.AttrMask, p9.Attr, error) { + ctx.UninterruptibleSleepStart(false) + qids, newfile, attrMask, attr, err := f.file.WalkGetAttr(names) + ctx.UninterruptibleSleepFinish(false) + return qids, p9file{newfile}, attrMask, attr, err +} + +// walkGetAttrOne is a wrapper around p9.File.WalkGetAttr that takes a single +// path component and returns a single qid. +func (f p9file) walkGetAttrOne(ctx context.Context, name string) (p9.QID, p9file, p9.AttrMask, p9.Attr, error) { + ctx.UninterruptibleSleepStart(false) + qids, newfile, attrMask, attr, err := f.file.WalkGetAttr([]string{name}) + ctx.UninterruptibleSleepFinish(false) + if err != nil { + return p9.QID{}, p9file{}, p9.AttrMask{}, p9.Attr{}, err + } + if len(qids) != 1 { + ctx.Warningf("p9.File.WalkGetAttr returned %d qids (%v), wanted 1", len(qids), qids) + if newfile != nil { + p9file{newfile}.close(ctx) + } + return p9.QID{}, p9file{}, p9.AttrMask{}, p9.Attr{}, syserror.EIO + } + return qids[0], p9file{newfile}, attrMask, attr, nil +} + +func (f p9file) statFS(ctx context.Context) (p9.FSStat, error) { + ctx.UninterruptibleSleepStart(false) + fsstat, err := f.file.StatFS() + ctx.UninterruptibleSleepFinish(false) + return fsstat, err +} + +func (f p9file) getAttr(ctx context.Context, req p9.AttrMask) (p9.QID, p9.AttrMask, p9.Attr, error) { + ctx.UninterruptibleSleepStart(false) + qid, attrMask, attr, err := f.file.GetAttr(req) + ctx.UninterruptibleSleepFinish(false) + return qid, attrMask, attr, err +} + +func (f p9file) setAttr(ctx context.Context, valid p9.SetAttrMask, attr p9.SetAttr) error { + ctx.UninterruptibleSleepStart(false) + err := f.file.SetAttr(valid, attr) + ctx.UninterruptibleSleepFinish(false) + return err +} + +func (f p9file) getXattr(ctx context.Context, name string, size uint64) (string, error) { + ctx.UninterruptibleSleepStart(false) + val, err := f.file.GetXattr(name, size) + ctx.UninterruptibleSleepFinish(false) + return val, err +} + +func (f p9file) setXattr(ctx context.Context, name, value string, flags uint32) error { + ctx.UninterruptibleSleepStart(false) + err := f.file.SetXattr(name, value, flags) + ctx.UninterruptibleSleepFinish(false) + return err +} + +func (f p9file) allocate(ctx context.Context, mode p9.AllocateMode, offset, length uint64) error { + ctx.UninterruptibleSleepStart(false) + err := f.file.Allocate(mode, offset, length) + ctx.UninterruptibleSleepFinish(false) + return err +} + +func (f p9file) close(ctx context.Context) error { + ctx.UninterruptibleSleepStart(false) + err := f.file.Close() + ctx.UninterruptibleSleepFinish(false) + return err +} + +func (f p9file) open(ctx context.Context, flags p9.OpenFlags) (*fd.FD, p9.QID, uint32, error) { + ctx.UninterruptibleSleepStart(false) + fdobj, qid, iounit, err := f.file.Open(flags) + ctx.UninterruptibleSleepFinish(false) + return fdobj, qid, iounit, err +} + +func (f p9file) readAt(ctx context.Context, p []byte, offset uint64) (int, error) { + ctx.UninterruptibleSleepStart(false) + n, err := f.file.ReadAt(p, offset) + ctx.UninterruptibleSleepFinish(false) + return n, err +} + +func (f p9file) writeAt(ctx context.Context, p []byte, offset uint64) (int, error) { + ctx.UninterruptibleSleepStart(false) + n, err := f.file.WriteAt(p, offset) + ctx.UninterruptibleSleepFinish(false) + return n, err +} + +func (f p9file) fsync(ctx context.Context) error { + ctx.UninterruptibleSleepStart(false) + err := f.file.FSync() + ctx.UninterruptibleSleepFinish(false) + return err +} + +func (f p9file) create(ctx context.Context, name string, flags p9.OpenFlags, permissions p9.FileMode, uid p9.UID, gid p9.GID) (*fd.FD, p9file, p9.QID, uint32, error) { + ctx.UninterruptibleSleepStart(false) + fdobj, newfile, qid, iounit, err := f.file.Create(name, flags, permissions, uid, gid) + ctx.UninterruptibleSleepFinish(false) + return fdobj, p9file{newfile}, qid, iounit, err +} + +func (f p9file) mkdir(ctx context.Context, name string, permissions p9.FileMode, uid p9.UID, gid p9.GID) (p9.QID, error) { + ctx.UninterruptibleSleepStart(false) + qid, err := f.file.Mkdir(name, permissions, uid, gid) + ctx.UninterruptibleSleepFinish(false) + return qid, err +} + +func (f p9file) symlink(ctx context.Context, oldName string, newName string, uid p9.UID, gid p9.GID) (p9.QID, error) { + ctx.UninterruptibleSleepStart(false) + qid, err := f.file.Symlink(oldName, newName, uid, gid) + ctx.UninterruptibleSleepFinish(false) + return qid, err +} + +func (f p9file) link(ctx context.Context, target p9file, newName string) error { + ctx.UninterruptibleSleepStart(false) + err := f.file.Link(target.file, newName) + ctx.UninterruptibleSleepFinish(false) + return err +} + +func (f p9file) mknod(ctx context.Context, name string, mode p9.FileMode, major uint32, minor uint32, uid p9.UID, gid p9.GID) (p9.QID, error) { + ctx.UninterruptibleSleepStart(false) + qid, err := f.file.Mknod(name, mode, major, minor, uid, gid) + ctx.UninterruptibleSleepFinish(false) + return qid, err +} + +func (f p9file) rename(ctx context.Context, newDir p9file, newName string) error { + ctx.UninterruptibleSleepStart(false) + err := f.file.Rename(newDir.file, newName) + ctx.UninterruptibleSleepFinish(false) + return err +} + +func (f p9file) unlinkAt(ctx context.Context, name string, flags uint32) error { + ctx.UninterruptibleSleepStart(false) + err := f.file.UnlinkAt(name, flags) + ctx.UninterruptibleSleepFinish(false) + return err +} + +func (f p9file) readdir(ctx context.Context, offset uint64, count uint32) ([]p9.Dirent, error) { + ctx.UninterruptibleSleepStart(false) + dirents, err := f.file.Readdir(offset, count) + ctx.UninterruptibleSleepFinish(false) + return dirents, err +} + +func (f p9file) readlink(ctx context.Context) (string, error) { + ctx.UninterruptibleSleepStart(false) + target, err := f.file.Readlink() + ctx.UninterruptibleSleepFinish(false) + return target, err +} + +func (f p9file) flush(ctx context.Context) error { + ctx.UninterruptibleSleepStart(false) + err := f.file.Flush() + ctx.UninterruptibleSleepFinish(false) + return err +} + +func (f p9file) connect(ctx context.Context, flags p9.ConnectFlags) (*fd.FD, error) { + ctx.UninterruptibleSleepStart(false) + fdobj, err := f.file.Connect(flags) + ctx.UninterruptibleSleepFinish(false) + return fdobj, err +} diff --git a/pkg/sentry/fsimpl/gofer/pagemath.go b/pkg/sentry/fsimpl/gofer/pagemath.go new file mode 100644 index 000000000..847cb0784 --- /dev/null +++ b/pkg/sentry/fsimpl/gofer/pagemath.go @@ -0,0 +1,31 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package gofer + +import ( + "gvisor.dev/gvisor/pkg/usermem" +) + +// This are equivalent to usermem.Addr.RoundDown/Up, but without the +// potentially truncating conversion to usermem.Addr. This is necessary because +// there is no way to define generic "PageRoundDown/Up" functions in Go. + +func pageRoundDown(x uint64) uint64 { + return x &^ (usermem.PageSize - 1) +} + +func pageRoundUp(x uint64) uint64 { + return pageRoundDown(x + usermem.PageSize - 1) +} diff --git a/pkg/sentry/fsimpl/gofer/regular_file.go b/pkg/sentry/fsimpl/gofer/regular_file.go new file mode 100644 index 000000000..8e11e06b3 --- /dev/null +++ b/pkg/sentry/fsimpl/gofer/regular_file.go @@ -0,0 +1,860 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package gofer + +import ( + "fmt" + "io" + "math" + "sync" + "sync/atomic" + + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/log" + "gvisor.dev/gvisor/pkg/safemem" + "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" + "gvisor.dev/gvisor/pkg/sentry/memmap" + "gvisor.dev/gvisor/pkg/sentry/pgalloc" + "gvisor.dev/gvisor/pkg/sentry/platform" + "gvisor.dev/gvisor/pkg/sentry/usage" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" +) + +func (d *dentry) isRegularFile() bool { + return d.fileType() == linux.S_IFREG +} + +type regularFileFD struct { + fileDescription + + // off is the file offset. off is protected by mu. + mu sync.Mutex + off int64 +} + +// Release implements vfs.FileDescriptionImpl.Release. +func (fd *regularFileFD) Release() { +} + +// OnClose implements vfs.FileDescriptionImpl.OnClose. +func (fd *regularFileFD) OnClose(ctx context.Context) error { + if !fd.vfsfd.IsWritable() { + return nil + } + // Skip flushing if writes may be buffered by the client, since (as with + // the VFS1 client) we don't flush buffered writes on close anyway. + d := fd.dentry() + if d.fs.opts.interop == InteropModeExclusive { + return nil + } + d.handleMu.RLock() + defer d.handleMu.RUnlock() + return d.handle.file.flush(ctx) +} + +// PRead implements vfs.FileDescriptionImpl.PRead. +func (fd *regularFileFD) PRead(ctx context.Context, dst usermem.IOSequence, offset int64, opts vfs.ReadOptions) (int64, error) { + if offset < 0 { + return 0, syserror.EINVAL + } + if opts.Flags != 0 { + return 0, syserror.EOPNOTSUPP + } + + // Check for reading at EOF before calling into MM (but not under + // InteropModeShared, which makes d.size unreliable). + d := fd.dentry() + if d.fs.opts.interop != InteropModeShared && uint64(offset) >= atomic.LoadUint64(&d.size) { + return 0, io.EOF + } + + if fd.vfsfd.StatusFlags()&linux.O_DIRECT != 0 { + // Lock d.metadataMu for the rest of the read to prevent d.size from + // changing. + d.metadataMu.Lock() + defer d.metadataMu.Unlock() + // Write dirty cached pages that will be touched by the read back to + // the remote file. + if err := d.writeback(ctx, offset, dst.NumBytes()); err != nil { + return 0, err + } + } + + rw := getDentryReadWriter(ctx, d, offset) + if fd.vfsfd.StatusFlags()&linux.O_DIRECT != 0 { + // Require the read to go to the remote file. + rw.direct = true + } + n, err := dst.CopyOutFrom(ctx, rw) + putDentryReadWriter(rw) + if d.fs.opts.interop != InteropModeShared { + // Compare Linux's mm/filemap.c:do_generic_file_read() => file_accessed(). + d.touchAtime(ctx, fd.vfsfd.Mount()) + } + return n, err +} + +// Read implements vfs.FileDescriptionImpl.Read. +func (fd *regularFileFD) Read(ctx context.Context, dst usermem.IOSequence, opts vfs.ReadOptions) (int64, error) { + fd.mu.Lock() + n, err := fd.PRead(ctx, dst, fd.off, opts) + fd.off += n + fd.mu.Unlock() + return n, err +} + +// PWrite implements vfs.FileDescriptionImpl.PWrite. +func (fd *regularFileFD) PWrite(ctx context.Context, src usermem.IOSequence, offset int64, opts vfs.WriteOptions) (int64, error) { + if offset < 0 { + return 0, syserror.EINVAL + } + if opts.Flags != 0 { + return 0, syserror.EOPNOTSUPP + } + + d := fd.dentry() + d.metadataMu.Lock() + defer d.metadataMu.Unlock() + if d.fs.opts.interop != InteropModeShared { + // Compare Linux's mm/filemap.c:__generic_file_write_iter() => + // file_update_time(). This is d.touchCMtime(), but without locking + // d.metadataMu (recursively). + if now, ok := nowFromContext(ctx); ok { + atomic.StoreInt64(&d.mtime, now) + atomic.StoreInt64(&d.ctime, now) + } + } + if fd.vfsfd.StatusFlags()&linux.O_DIRECT != 0 { + // Write dirty cached pages that will be touched by the write back to + // the remote file. + if err := d.writeback(ctx, offset, src.NumBytes()); err != nil { + return 0, err + } + // Remove touched pages from the cache. + pgstart := pageRoundDown(uint64(offset)) + pgend := pageRoundUp(uint64(offset + src.NumBytes())) + if pgend < pgstart { + return 0, syserror.EINVAL + } + mr := memmap.MappableRange{pgstart, pgend} + var freed []platform.FileRange + d.dataMu.Lock() + cseg := d.cache.LowerBoundSegment(mr.Start) + for cseg.Ok() && cseg.Start() < mr.End { + cseg = d.cache.Isolate(cseg, mr) + freed = append(freed, platform.FileRange{cseg.Value(), cseg.Value() + cseg.Range().Length()}) + cseg = d.cache.Remove(cseg).NextSegment() + } + d.dataMu.Unlock() + // Invalidate mappings of removed pages. + d.mapsMu.Lock() + d.mappings.Invalidate(mr, memmap.InvalidateOpts{}) + d.mapsMu.Unlock() + // Finally free pages removed from the cache. + mf := d.fs.mfp.MemoryFile() + for _, freedFR := range freed { + mf.DecRef(freedFR) + } + } + rw := getDentryReadWriter(ctx, d, offset) + if fd.vfsfd.StatusFlags()&linux.O_DIRECT != 0 { + // Require the write to go to the remote file. + rw.direct = true + } + n, err := src.CopyInTo(ctx, rw) + putDentryReadWriter(rw) + if n != 0 && fd.vfsfd.StatusFlags()&(linux.O_DSYNC|linux.O_SYNC) != 0 { + // Write dirty cached pages touched by the write back to the remote + // file. + if err := d.writeback(ctx, offset, src.NumBytes()); err != nil { + return 0, err + } + // Request the remote filesystem to sync the remote file. + if err := d.handle.file.fsync(ctx); err != nil { + return 0, err + } + } + return n, err +} + +// Write implements vfs.FileDescriptionImpl.Write. +func (fd *regularFileFD) Write(ctx context.Context, src usermem.IOSequence, opts vfs.WriteOptions) (int64, error) { + fd.mu.Lock() + n, err := fd.PWrite(ctx, src, fd.off, opts) + fd.off += n + fd.mu.Unlock() + return n, err +} + +type dentryReadWriter struct { + ctx context.Context + d *dentry + off uint64 + direct bool +} + +var dentryReadWriterPool = sync.Pool{ + New: func() interface{} { + return &dentryReadWriter{} + }, +} + +func getDentryReadWriter(ctx context.Context, d *dentry, offset int64) *dentryReadWriter { + rw := dentryReadWriterPool.Get().(*dentryReadWriter) + rw.ctx = ctx + rw.d = d + rw.off = uint64(offset) + rw.direct = false + return rw +} + +func putDentryReadWriter(rw *dentryReadWriter) { + rw.ctx = nil + rw.d = nil + dentryReadWriterPool.Put(rw) +} + +// ReadToBlocks implements safemem.Reader.ReadToBlocks. +func (rw *dentryReadWriter) ReadToBlocks(dsts safemem.BlockSeq) (uint64, error) { + if dsts.IsEmpty() { + return 0, nil + } + + // If we have a mmappable host FD (which must be used here to ensure + // coherence with memory-mapped I/O), or if InteropModeShared is in effect + // (which prevents us from caching file contents and makes dentry.size + // unreliable), or if the file was opened O_DIRECT, read directly from + // dentry.handle without locking dentry.dataMu. + rw.d.handleMu.RLock() + if (rw.d.handle.fd >= 0 && !rw.d.fs.opts.forcePageCache) || rw.d.fs.opts.interop == InteropModeShared || rw.direct { + n, err := rw.d.handle.readToBlocksAt(rw.ctx, dsts, rw.off) + rw.d.handleMu.RUnlock() + rw.off += n + return n, err + } + + // Otherwise read from/through the cache. + mf := rw.d.fs.mfp.MemoryFile() + fillCache := mf.ShouldCacheEvictable() + var dataMuUnlock func() + if fillCache { + rw.d.dataMu.Lock() + dataMuUnlock = rw.d.dataMu.Unlock + } else { + rw.d.dataMu.RLock() + dataMuUnlock = rw.d.dataMu.RUnlock + } + + // Compute the range to read (limited by file size and overflow-checked). + if rw.off >= rw.d.size { + dataMuUnlock() + rw.d.handleMu.RUnlock() + return 0, io.EOF + } + end := rw.d.size + if rend := rw.off + dsts.NumBytes(); rend > rw.off && rend < end { + end = rend + } + + var done uint64 + seg, gap := rw.d.cache.Find(rw.off) + for rw.off < end { + mr := memmap.MappableRange{rw.off, end} + switch { + case seg.Ok(): + // Get internal mappings from the cache. + ims, err := mf.MapInternal(seg.FileRangeOf(seg.Range().Intersect(mr)), usermem.Read) + if err != nil { + dataMuUnlock() + rw.d.handleMu.RUnlock() + return done, err + } + + // Copy from internal mappings. + n, err := safemem.CopySeq(dsts, ims) + done += n + rw.off += n + dsts = dsts.DropFirst64(n) + if err != nil { + dataMuUnlock() + rw.d.handleMu.RUnlock() + return done, err + } + + // Continue. + seg, gap = seg.NextNonEmpty() + + case gap.Ok(): + gapMR := gap.Range().Intersect(mr) + if fillCache { + // Read into the cache, then re-enter the loop to read from the + // cache. + reqMR := memmap.MappableRange{ + Start: pageRoundDown(gapMR.Start), + End: pageRoundUp(gapMR.End), + } + optMR := gap.Range() + err := rw.d.cache.Fill(rw.ctx, reqMR, maxFillRange(reqMR, optMR), mf, usage.PageCache, rw.d.handle.readToBlocksAt) + mf.MarkEvictable(rw.d, pgalloc.EvictableRange{optMR.Start, optMR.End}) + seg, gap = rw.d.cache.Find(rw.off) + if !seg.Ok() { + dataMuUnlock() + rw.d.handleMu.RUnlock() + return done, err + } + // err might have occurred in part of gap.Range() outside + // gapMR. Forget about it for now; if the error matters and + // persists, we'll run into it again in a later iteration of + // this loop. + } else { + // Read directly from the file. + gapDsts := dsts.TakeFirst64(gapMR.Length()) + n, err := rw.d.handle.readToBlocksAt(rw.ctx, gapDsts, gapMR.Start) + done += n + rw.off += n + dsts = dsts.DropFirst64(n) + // Partial reads are fine. But we must stop reading. + if n != gapDsts.NumBytes() || err != nil { + dataMuUnlock() + rw.d.handleMu.RUnlock() + return done, err + } + + // Continue. + seg, gap = gap.NextSegment(), fsutil.FileRangeGapIterator{} + } + } + } + dataMuUnlock() + rw.d.handleMu.RUnlock() + return done, nil +} + +// WriteFromBlocks implements safemem.Writer.WriteFromBlocks. +// +// Preconditions: rw.d.metadataMu must be locked. +func (rw *dentryReadWriter) WriteFromBlocks(srcs safemem.BlockSeq) (uint64, error) { + if srcs.IsEmpty() { + return 0, nil + } + + // If we have a mmappable host FD (which must be used here to ensure + // coherence with memory-mapped I/O), or if InteropModeShared is in effect + // (which prevents us from caching file contents), or if the file was + // opened with O_DIRECT, write directly to dentry.handle without locking + // dentry.dataMu. + rw.d.handleMu.RLock() + if (rw.d.handle.fd >= 0 && !rw.d.fs.opts.forcePageCache) || rw.d.fs.opts.interop == InteropModeShared || rw.direct { + n, err := rw.d.handle.writeFromBlocksAt(rw.ctx, srcs, rw.off) + rw.d.handleMu.RUnlock() + rw.off += n + return n, err + } + + // Otherwise write to/through the cache. + mf := rw.d.fs.mfp.MemoryFile() + rw.d.dataMu.Lock() + + // Compute the range to write (overflow-checked). + start := rw.off + end := rw.off + srcs.NumBytes() + if end <= rw.off { + end = math.MaxInt64 + } + + var ( + done uint64 + retErr error + ) + seg, gap := rw.d.cache.Find(rw.off) + for rw.off < end { + mr := memmap.MappableRange{rw.off, end} + switch { + case seg.Ok(): + // Get internal mappings from the cache. + segMR := seg.Range().Intersect(mr) + ims, err := mf.MapInternal(seg.FileRangeOf(segMR), usermem.Write) + if err != nil { + retErr = err + goto exitLoop + } + + // Copy to internal mappings. + n, err := safemem.CopySeq(ims, srcs) + done += n + rw.off += n + srcs = srcs.DropFirst64(n) + rw.d.dirty.MarkDirty(segMR) + if err != nil { + retErr = err + goto exitLoop + } + + // Continue. + seg, gap = seg.NextNonEmpty() + + case gap.Ok(): + // Write directly to the file. At present, we never fill the cache + // when writing, since doing so can convert small writes into + // inefficient read-modify-write cycles, and we have no mechanism + // for detecting or avoiding this. + gapMR := gap.Range().Intersect(mr) + gapSrcs := srcs.TakeFirst64(gapMR.Length()) + n, err := rw.d.handle.writeFromBlocksAt(rw.ctx, gapSrcs, gapMR.Start) + done += n + rw.off += n + srcs = srcs.DropFirst64(n) + // Partial writes are fine. But we must stop writing. + if n != gapSrcs.NumBytes() || err != nil { + retErr = err + goto exitLoop + } + + // Continue. + seg, gap = gap.NextSegment(), fsutil.FileRangeGapIterator{} + } + } +exitLoop: + if rw.off > rw.d.size { + atomic.StoreUint64(&rw.d.size, rw.off) + // The remote file's size will implicitly be extended to the correct + // value when we write back to it. + } + // If InteropModeWritethrough is in effect, flush written data back to the + // remote filesystem. + if rw.d.fs.opts.interop == InteropModeWritethrough && done != 0 { + if err := fsutil.SyncDirty(rw.ctx, memmap.MappableRange{ + Start: start, + End: rw.off, + }, &rw.d.cache, &rw.d.dirty, rw.d.size, mf, rw.d.handle.writeFromBlocksAt); err != nil { + // We have no idea how many bytes were actually flushed. + rw.off = start + done = 0 + retErr = err + } + } + rw.d.dataMu.Unlock() + rw.d.handleMu.RUnlock() + return done, retErr +} + +func (d *dentry) writeback(ctx context.Context, offset, size int64) error { + if size == 0 { + return nil + } + d.handleMu.RLock() + defer d.handleMu.RUnlock() + d.dataMu.Lock() + defer d.dataMu.Unlock() + // Compute the range of valid bytes (overflow-checked). + if uint64(offset) >= d.size { + return nil + } + end := int64(d.size) + if rend := offset + size; rend > offset && rend < end { + end = rend + } + return fsutil.SyncDirty(ctx, memmap.MappableRange{ + Start: uint64(offset), + End: uint64(end), + }, &d.cache, &d.dirty, d.size, d.fs.mfp.MemoryFile(), d.handle.writeFromBlocksAt) +} + +// Seek implements vfs.FileDescriptionImpl.Seek. +func (fd *regularFileFD) Seek(ctx context.Context, offset int64, whence int32) (int64, error) { + fd.mu.Lock() + defer fd.mu.Unlock() + switch whence { + case linux.SEEK_SET: + // Use offset as specified. + case linux.SEEK_CUR: + offset += fd.off + case linux.SEEK_END, linux.SEEK_DATA, linux.SEEK_HOLE: + // Ensure file size is up to date. + d := fd.dentry() + if fd.filesystem().opts.interop == InteropModeShared { + if err := d.updateFromGetattr(ctx); err != nil { + return 0, err + } + } + size := int64(atomic.LoadUint64(&d.size)) + // For SEEK_DATA and SEEK_HOLE, treat the file as a single contiguous + // block of data. + switch whence { + case linux.SEEK_END: + offset += size + case linux.SEEK_DATA: + if offset > size { + return 0, syserror.ENXIO + } + // Use offset as specified. + case linux.SEEK_HOLE: + if offset > size { + return 0, syserror.ENXIO + } + offset = size + } + default: + return 0, syserror.EINVAL + } + if offset < 0 { + return 0, syserror.EINVAL + } + fd.off = offset + return offset, nil +} + +// Sync implements vfs.FileDescriptionImpl.Sync. +func (fd *regularFileFD) Sync(ctx context.Context) error { + return fd.dentry().syncSharedHandle(ctx) +} + +func (d *dentry) syncSharedHandle(ctx context.Context) error { + d.handleMu.RLock() + if !d.handleWritable { + d.handleMu.RUnlock() + return nil + } + d.dataMu.Lock() + // Write dirty cached data to the remote file. + err := fsutil.SyncDirtyAll(ctx, &d.cache, &d.dirty, d.size, d.fs.mfp.MemoryFile(), d.handle.writeFromBlocksAt) + d.dataMu.Unlock() + if err == nil { + // Sync the remote file. + err = d.handle.sync(ctx) + } + d.handleMu.RUnlock() + return err +} + +// ConfigureMMap implements vfs.FileDescriptionImpl.ConfigureMMap. +func (fd *regularFileFD) ConfigureMMap(ctx context.Context, opts *memmap.MMapOpts) error { + d := fd.dentry() + switch d.fs.opts.interop { + case InteropModeExclusive: + // Any mapping is fine. + case InteropModeWritethrough: + // Shared writable mappings require a host FD, since otherwise we can't + // synchronously flush memory-mapped writes to the remote file. + if opts.Private || !opts.MaxPerms.Write { + break + } + fallthrough + case InteropModeShared: + // All mappings require a host FD to be coherent with other filesystem + // users. + if d.fs.opts.forcePageCache { + // Whether or not we have a host FD, we're not allowed to use it. + return syserror.ENODEV + } + d.handleMu.RLock() + haveFD := d.handle.fd >= 0 + d.handleMu.RUnlock() + if !haveFD { + return syserror.ENODEV + } + default: + panic(fmt.Sprintf("unknown InteropMode %v", d.fs.opts.interop)) + } + return vfs.GenericConfigureMMap(&fd.vfsfd, d, opts) +} + +func (d *dentry) mayCachePages() bool { + if d.fs.opts.interop == InteropModeShared { + return false + } + if d.fs.opts.forcePageCache { + return true + } + d.handleMu.RLock() + haveFD := d.handle.fd >= 0 + d.handleMu.RUnlock() + return haveFD +} + +// AddMapping implements memmap.Mappable.AddMapping. +func (d *dentry) AddMapping(ctx context.Context, ms memmap.MappingSpace, ar usermem.AddrRange, offset uint64, writable bool) error { + d.mapsMu.Lock() + mapped := d.mappings.AddMapping(ms, ar, offset, writable) + // Do this unconditionally since whether we have a host FD can change + // across save/restore. + for _, r := range mapped { + d.pf.hostFileMapper.IncRefOn(r) + } + if d.mayCachePages() { + // d.Evict() will refuse to evict memory-mapped pages, so tell the + // MemoryFile to not bother trying. + mf := d.fs.mfp.MemoryFile() + for _, r := range mapped { + mf.MarkUnevictable(d, pgalloc.EvictableRange{r.Start, r.End}) + } + } + d.mapsMu.Unlock() + return nil +} + +// RemoveMapping implements memmap.Mappable.RemoveMapping. +func (d *dentry) RemoveMapping(ctx context.Context, ms memmap.MappingSpace, ar usermem.AddrRange, offset uint64, writable bool) { + d.mapsMu.Lock() + unmapped := d.mappings.RemoveMapping(ms, ar, offset, writable) + for _, r := range unmapped { + d.pf.hostFileMapper.DecRefOn(r) + } + if d.mayCachePages() { + // Pages that are no longer referenced by any application memory + // mappings are now considered unused; allow MemoryFile to evict them + // when necessary. + mf := d.fs.mfp.MemoryFile() + d.dataMu.Lock() + for _, r := range unmapped { + // Since these pages are no longer mapped, they are no longer + // concurrently dirtyable by a writable memory mapping. + d.dirty.AllowClean(r) + mf.MarkEvictable(d, pgalloc.EvictableRange{r.Start, r.End}) + } + d.dataMu.Unlock() + } + d.mapsMu.Unlock() +} + +// CopyMapping implements memmap.Mappable.CopyMapping. +func (d *dentry) CopyMapping(ctx context.Context, ms memmap.MappingSpace, srcAR, dstAR usermem.AddrRange, offset uint64, writable bool) error { + return d.AddMapping(ctx, ms, dstAR, offset, writable) +} + +// Translate implements memmap.Mappable.Translate. +func (d *dentry) Translate(ctx context.Context, required, optional memmap.MappableRange, at usermem.AccessType) ([]memmap.Translation, error) { + d.handleMu.RLock() + if d.handle.fd >= 0 && !d.fs.opts.forcePageCache { + d.handleMu.RUnlock() + mr := optional + if d.fs.opts.limitHostFDTranslation { + mr = maxFillRange(required, optional) + } + return []memmap.Translation{ + { + Source: mr, + File: &d.pf, + Offset: mr.Start, + Perms: usermem.AnyAccess, + }, + }, nil + } + + d.dataMu.Lock() + + // Constrain translations to d.size (rounded up) to prevent translation to + // pages that may be concurrently truncated. + pgend := pageRoundUp(d.size) + var beyondEOF bool + if required.End > pgend { + if required.Start >= pgend { + d.dataMu.Unlock() + d.handleMu.RUnlock() + return nil, &memmap.BusError{io.EOF} + } + beyondEOF = true + required.End = pgend + } + if optional.End > pgend { + optional.End = pgend + } + + mf := d.fs.mfp.MemoryFile() + cerr := d.cache.Fill(ctx, required, maxFillRange(required, optional), mf, usage.PageCache, d.handle.readToBlocksAt) + + var ts []memmap.Translation + var translatedEnd uint64 + for seg := d.cache.FindSegment(required.Start); seg.Ok() && seg.Start() < required.End; seg, _ = seg.NextNonEmpty() { + segMR := seg.Range().Intersect(optional) + // TODO(jamieliu): Make Translations writable even if writability is + // not required if already kept-dirty by another writable translation. + perms := usermem.AccessType{ + Read: true, + Execute: true, + } + if at.Write { + // From this point forward, this memory can be dirtied through the + // mapping at any time. + d.dirty.KeepDirty(segMR) + perms.Write = true + } + ts = append(ts, memmap.Translation{ + Source: segMR, + File: mf, + Offset: seg.FileRangeOf(segMR).Start, + Perms: perms, + }) + translatedEnd = segMR.End + } + + d.dataMu.Unlock() + d.handleMu.RUnlock() + + // Don't return the error returned by c.cache.Fill if it occurred outside + // of required. + if translatedEnd < required.End && cerr != nil { + return ts, &memmap.BusError{cerr} + } + if beyondEOF { + return ts, &memmap.BusError{io.EOF} + } + return ts, nil +} + +func maxFillRange(required, optional memmap.MappableRange) memmap.MappableRange { + const maxReadahead = 64 << 10 // 64 KB, chosen arbitrarily + if required.Length() >= maxReadahead { + return required + } + if optional.Length() <= maxReadahead { + return optional + } + optional.Start = required.Start + if optional.Length() <= maxReadahead { + return optional + } + optional.End = optional.Start + maxReadahead + return optional +} + +// InvalidateUnsavable implements memmap.Mappable.InvalidateUnsavable. +func (d *dentry) InvalidateUnsavable(ctx context.Context) error { + // Whether we have a host fd (and consequently what platform.File is + // mapped) can change across save/restore, so invalidate all translations + // unconditionally. + d.mapsMu.Lock() + defer d.mapsMu.Unlock() + d.mappings.InvalidateAll(memmap.InvalidateOpts{}) + + // Write the cache's contents back to the remote file so that if we have a + // host fd after restore, the remote file's contents are coherent. + mf := d.fs.mfp.MemoryFile() + d.dataMu.Lock() + defer d.dataMu.Unlock() + if err := fsutil.SyncDirtyAll(ctx, &d.cache, &d.dirty, d.size, mf, d.handle.writeFromBlocksAt); err != nil { + return err + } + + // Discard the cache so that it's not stored in saved state. This is safe + // because per InvalidateUnsavable invariants, no new translations can have + // been returned after we invalidated all existing translations above. + d.cache.DropAll(mf) + d.dirty.RemoveAll() + + return nil +} + +// Evict implements pgalloc.EvictableMemoryUser.Evict. +func (d *dentry) Evict(ctx context.Context, er pgalloc.EvictableRange) { + d.mapsMu.Lock() + defer d.mapsMu.Unlock() + d.dataMu.Lock() + defer d.dataMu.Unlock() + + mr := memmap.MappableRange{er.Start, er.End} + mf := d.fs.mfp.MemoryFile() + // Only allow pages that are no longer memory-mapped to be evicted. + for mgap := d.mappings.LowerBoundGap(mr.Start); mgap.Ok() && mgap.Start() < mr.End; mgap = mgap.NextGap() { + mgapMR := mgap.Range().Intersect(mr) + if mgapMR.Length() == 0 { + continue + } + if err := fsutil.SyncDirty(ctx, mgapMR, &d.cache, &d.dirty, d.size, mf, d.handle.writeFromBlocksAt); err != nil { + log.Warningf("Failed to writeback cached data %v: %v", mgapMR, err) + } + d.cache.Drop(mgapMR, mf) + d.dirty.KeepClean(mgapMR) + } +} + +// dentryPlatformFile implements platform.File. It exists solely because dentry +// cannot implement both vfs.DentryImpl.IncRef and platform.File.IncRef. +// +// dentryPlatformFile is only used when a host FD representing the remote file +// is available (i.e. dentry.handle.fd >= 0), and that FD is used for +// application memory mappings (i.e. !filesystem.opts.forcePageCache). +type dentryPlatformFile struct { + *dentry + + // fdRefs counts references on platform.File offsets. fdRefs is protected + // by dentry.dataMu. + fdRefs fsutil.FrameRefSet + + // If this dentry represents a regular file, and handle.fd >= 0, + // hostFileMapper caches mappings of handle.fd. + hostFileMapper fsutil.HostFileMapper +} + +// IncRef implements platform.File.IncRef. +func (d *dentryPlatformFile) IncRef(fr platform.FileRange) { + d.dataMu.Lock() + seg, gap := d.fdRefs.Find(fr.Start) + for { + switch { + case seg.Ok() && seg.Start() < fr.End: + seg = d.fdRefs.Isolate(seg, fr) + seg.SetValue(seg.Value() + 1) + seg, gap = seg.NextNonEmpty() + case gap.Ok() && gap.Start() < fr.End: + newRange := gap.Range().Intersect(fr) + usage.MemoryAccounting.Inc(newRange.Length(), usage.Mapped) + seg, gap = d.fdRefs.InsertWithoutMerging(gap, newRange, 1).NextNonEmpty() + default: + d.fdRefs.MergeAdjacent(fr) + d.dataMu.Unlock() + return + } + } +} + +// DecRef implements platform.File.DecRef. +func (d *dentryPlatformFile) DecRef(fr platform.FileRange) { + d.dataMu.Lock() + seg := d.fdRefs.FindSegment(fr.Start) + + for seg.Ok() && seg.Start() < fr.End { + seg = d.fdRefs.Isolate(seg, fr) + if old := seg.Value(); old == 1 { + usage.MemoryAccounting.Dec(seg.Range().Length(), usage.Mapped) + seg = d.fdRefs.Remove(seg).NextSegment() + } else { + seg.SetValue(old - 1) + seg = seg.NextSegment() + } + } + d.fdRefs.MergeAdjacent(fr) + d.dataMu.Unlock() + +} + +// MapInternal implements platform.File.MapInternal. +func (d *dentryPlatformFile) MapInternal(fr platform.FileRange, at usermem.AccessType) (safemem.BlockSeq, error) { + d.handleMu.RLock() + bs, err := d.hostFileMapper.MapInternal(fr, int(d.handle.fd), at.Write) + d.handleMu.RUnlock() + return bs, err +} + +// FD implements platform.File.FD. +func (d *dentryPlatformFile) FD() int { + d.handleMu.RLock() + fd := d.handle.fd + d.handleMu.RUnlock() + return int(fd) +} diff --git a/pkg/sentry/fsimpl/gofer/special_file.go b/pkg/sentry/fsimpl/gofer/special_file.go new file mode 100644 index 000000000..08c691c47 --- /dev/null +++ b/pkg/sentry/fsimpl/gofer/special_file.go @@ -0,0 +1,159 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package gofer + +import ( + "sync" + + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/safemem" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" +) + +// specialFileFD implements vfs.FileDescriptionImpl for files other than +// regular files, directories, and symlinks: pipes, sockets, etc. It is also +// used for regular files when filesystemOptions.specialRegularFiles is in +// effect. specialFileFD differs from regularFileFD by using per-FD handles +// instead of shared per-dentry handles, and never buffering I/O. +type specialFileFD struct { + fileDescription + + // handle is immutable. + handle handle + + // off is the file offset. off is protected by mu. (POSIX 2.9.7 only + // requires operations using the file offset to be atomic for regular files + // and symlinks; however, since specialFileFD may be used for regular + // files, we apply this atomicity unconditionally.) + mu sync.Mutex + off int64 +} + +// Release implements vfs.FileDescriptionImpl.Release. +func (fd *specialFileFD) Release() { + fd.handle.close(context.Background()) + fs := fd.vfsfd.Mount().Filesystem().Impl().(*filesystem) + fs.syncMu.Lock() + delete(fs.specialFileFDs, fd) + fs.syncMu.Unlock() +} + +// OnClose implements vfs.FileDescriptionImpl.OnClose. +func (fd *specialFileFD) OnClose(ctx context.Context) error { + if !fd.vfsfd.IsWritable() { + return nil + } + return fd.handle.file.flush(ctx) +} + +// PRead implements vfs.FileDescriptionImpl.PRead. +func (fd *specialFileFD) PRead(ctx context.Context, dst usermem.IOSequence, offset int64, opts vfs.ReadOptions) (int64, error) { + if offset < 0 { + return 0, syserror.EINVAL + } + if opts.Flags != 0 { + return 0, syserror.EOPNOTSUPP + } + + // Going through dst.CopyOutFrom() holds MM locks around file operations of + // unknown duration. For regularFileFD, doing so is necessary to support + // mmap due to lock ordering; MM locks precede dentry.dataMu. That doesn't + // hold here since specialFileFD doesn't client-cache data. Just buffer the + // read instead. + if d := fd.dentry(); d.fs.opts.interop != InteropModeShared { + d.touchAtime(ctx, fd.vfsfd.Mount()) + } + buf := make([]byte, dst.NumBytes()) + n, err := fd.handle.readToBlocksAt(ctx, safemem.BlockSeqOf(safemem.BlockFromSafeSlice(buf)), uint64(offset)) + if n == 0 { + return 0, err + } + if cp, cperr := dst.CopyOut(ctx, buf[:n]); cperr != nil { + return int64(cp), cperr + } + return int64(n), err +} + +// Read implements vfs.FileDescriptionImpl.Read. +func (fd *specialFileFD) Read(ctx context.Context, dst usermem.IOSequence, opts vfs.ReadOptions) (int64, error) { + fd.mu.Lock() + n, err := fd.PRead(ctx, dst, fd.off, opts) + fd.off += n + fd.mu.Unlock() + return n, err +} + +// PWrite implements vfs.FileDescriptionImpl.PWrite. +func (fd *specialFileFD) PWrite(ctx context.Context, src usermem.IOSequence, offset int64, opts vfs.WriteOptions) (int64, error) { + if offset < 0 { + return 0, syserror.EINVAL + } + if opts.Flags != 0 { + return 0, syserror.EOPNOTSUPP + } + + // Do a buffered write. See rationale in PRead. + if d := fd.dentry(); d.fs.opts.interop != InteropModeShared { + d.touchCMtime(ctx) + } + buf := make([]byte, src.NumBytes()) + // Don't do partial writes if we get a partial read from src. + if _, err := src.CopyIn(ctx, buf); err != nil { + return 0, err + } + n, err := fd.handle.writeFromBlocksAt(ctx, safemem.BlockSeqOf(safemem.BlockFromSafeSlice(buf)), uint64(offset)) + return int64(n), err +} + +// Write implements vfs.FileDescriptionImpl.Write. +func (fd *specialFileFD) Write(ctx context.Context, src usermem.IOSequence, opts vfs.WriteOptions) (int64, error) { + fd.mu.Lock() + n, err := fd.PWrite(ctx, src, fd.off, opts) + fd.off += n + fd.mu.Unlock() + return n, err +} + +// Seek implements vfs.FileDescriptionImpl.Seek. +func (fd *specialFileFD) Seek(ctx context.Context, offset int64, whence int32) (int64, error) { + fd.mu.Lock() + defer fd.mu.Unlock() + switch whence { + case linux.SEEK_SET: + // Use offset as given. + case linux.SEEK_CUR: + offset += fd.off + default: + // SEEK_END, SEEK_DATA, and SEEK_HOLE aren't supported since it's not + // clear that file size is even meaningful for these files. + return 0, syserror.EINVAL + } + if offset < 0 { + return 0, syserror.EINVAL + } + fd.off = offset + return offset, nil +} + +// Sync implements vfs.FileDescriptionImpl.Sync. +func (fd *specialFileFD) Sync(ctx context.Context) error { + if !fd.vfsfd.IsWritable() { + return nil + } + return fd.handle.sync(ctx) +} diff --git a/pkg/sentry/fsimpl/gofer/symlink.go b/pkg/sentry/fsimpl/gofer/symlink.go new file mode 100644 index 000000000..adf43be60 --- /dev/null +++ b/pkg/sentry/fsimpl/gofer/symlink.go @@ -0,0 +1,47 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package gofer + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/sentry/vfs" +) + +func (d *dentry) isSymlink() bool { + return d.fileType() == linux.S_IFLNK +} + +// Precondition: d.isSymlink(). +func (d *dentry) readlink(ctx context.Context, mnt *vfs.Mount) (string, error) { + if d.fs.opts.interop != InteropModeShared { + d.touchAtime(ctx, mnt) + d.dataMu.Lock() + if d.haveTarget { + target := d.target + d.dataMu.Unlock() + return target, nil + } + } + target, err := d.file.readlink(ctx) + if d.fs.opts.interop != InteropModeShared { + if err == nil { + d.haveTarget = true + d.target = target + } + d.dataMu.Unlock() + } + return target, err +} diff --git a/pkg/sentry/fsimpl/gofer/time.go b/pkg/sentry/fsimpl/gofer/time.go new file mode 100644 index 000000000..7598ec6a8 --- /dev/null +++ b/pkg/sentry/fsimpl/gofer/time.go @@ -0,0 +1,75 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package gofer + +import ( + "sync/atomic" + + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" + ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" + "gvisor.dev/gvisor/pkg/sentry/vfs" +) + +func dentryTimestampFromP9(s, ns uint64) int64 { + return int64(s*1e9 + ns) +} + +func dentryTimestampFromStatx(ts linux.StatxTimestamp) int64 { + return ts.Sec*1e9 + int64(ts.Nsec) +} + +func statxTimestampFromDentry(ns int64) linux.StatxTimestamp { + return linux.StatxTimestamp{ + Sec: ns / 1e9, + Nsec: uint32(ns % 1e9), + } +} + +func nowFromContext(ctx context.Context) (int64, bool) { + if clock := ktime.RealtimeClockFromContext(ctx); clock != nil { + return clock.Now().Nanoseconds(), true + } + return 0, false +} + +// Preconditions: fs.interop != InteropModeShared. +func (d *dentry) touchAtime(ctx context.Context, mnt *vfs.Mount) { + if err := mnt.CheckBeginWrite(); err != nil { + return + } + now, ok := nowFromContext(ctx) + if !ok { + mnt.EndWrite() + return + } + d.metadataMu.Lock() + atomic.StoreInt64(&d.atime, now) + d.metadataMu.Unlock() + mnt.EndWrite() +} + +// Preconditions: fs.interop != InteropModeShared. The caller has successfully +// called vfs.Mount.CheckBeginWrite(). +func (d *dentry) touchCMtime(ctx context.Context) { + now, ok := nowFromContext(ctx) + if !ok { + return + } + d.metadataMu.Lock() + atomic.StoreInt64(&d.mtime, now) + atomic.StoreInt64(&d.ctime, now) + d.metadataMu.Unlock() +} diff --git a/pkg/sentry/fsimpl/tmpfs/filesystem.go b/pkg/sentry/fsimpl/tmpfs/filesystem.go index 5ee9cf1e9..72bc15264 100644 --- a/pkg/sentry/fsimpl/tmpfs/filesystem.go +++ b/pkg/sentry/fsimpl/tmpfs/filesystem.go @@ -622,7 +622,7 @@ func (fs *filesystem) UnlinkAt(ctx context.Context, rp *vfs.ResolvingPath) error if child.inode.isDir() { return syserror.EISDIR } - if !rp.MustBeDir() { + if rp.MustBeDir() { return syserror.ENOTDIR } mnt := rp.Mount() diff --git a/pkg/sentry/socket/hostinet/socket.go b/pkg/sentry/socket/hostinet/socket.go index bde4c7a1e..34f63986f 100644 --- a/pkg/sentry/socket/hostinet/socket.go +++ b/pkg/sentry/socket/hostinet/socket.go @@ -126,7 +126,7 @@ func (s *socketOperations) Read(ctx context.Context, _ *fs.File, dst usermem.IOS } return uint64(n), nil } - return readv(s.fd, iovecsFromBlockSeq(dsts)) + return readv(s.fd, safemem.IovecsFromBlockSeq(dsts)) })) return int64(n), err } @@ -149,7 +149,7 @@ func (s *socketOperations) Write(ctx context.Context, _ *fs.File, src usermem.IO } return uint64(n), nil } - return writev(s.fd, iovecsFromBlockSeq(srcs)) + return writev(s.fd, safemem.IovecsFromBlockSeq(srcs)) })) return int64(n), err } @@ -402,7 +402,7 @@ func (s *socketOperations) RecvMsg(t *kernel.Task, dst usermem.IOSequence, flags // We always do a non-blocking recv*(). sysflags := flags | syscall.MSG_DONTWAIT - iovs := iovecsFromBlockSeq(dsts) + iovs := safemem.IovecsFromBlockSeq(dsts) msg := syscall.Msghdr{ Iov: &iovs[0], Iovlen: uint64(len(iovs)), @@ -522,7 +522,7 @@ func (s *socketOperations) SendMsg(t *kernel.Task, src usermem.IOSequence, to [] return uint64(n), nil } - iovs := iovecsFromBlockSeq(srcs) + iovs := safemem.IovecsFromBlockSeq(srcs) msg := syscall.Msghdr{ Iov: &iovs[0], Iovlen: uint64(len(iovs)), @@ -567,21 +567,6 @@ func (s *socketOperations) SendMsg(t *kernel.Task, src usermem.IOSequence, to [] return int(n), syserr.FromError(err) } -func iovecsFromBlockSeq(bs safemem.BlockSeq) []syscall.Iovec { - iovs := make([]syscall.Iovec, 0, bs.NumBlocks()) - for ; !bs.IsEmpty(); bs = bs.Tail() { - b := bs.Head() - iovs = append(iovs, syscall.Iovec{ - Base: &b.ToSlice()[0], - Len: uint64(b.Len()), - }) - // We don't need to care about b.NeedSafecopy(), because the host - // kernel will handle such address ranges just fine (by returning - // EFAULT). - } - return iovs -} - func translateIOSyscallError(err error) error { if err == syscall.EAGAIN || err == syscall.EWOULDBLOCK { return syserror.ErrWouldBlock -- cgit v1.2.3 From a6024f7f5f6f438c11e30be0f93657b1956fd5ba Mon Sep 17 00:00:00 2001 From: gVisor bot Date: Thu, 13 Feb 2020 17:56:34 -0800 Subject: Add FileExec flag to OpenOptions This allow callers to say whether the file is being opened to be executed, so that the proper checks can be done from FilesystemImpl.OpenAt() Updates #1623 PiperOrigin-RevId: 295042595 --- pkg/sentry/fsimpl/ext/filesystem.go | 2 +- pkg/sentry/fsimpl/ext/inode.go | 12 ++++++------ pkg/sentry/fsimpl/gofer/filesystem.go | 24 ++++++++++++------------ pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go | 4 ++-- pkg/sentry/fsimpl/kernfs/fd_impl_util.go | 6 +++--- pkg/sentry/fsimpl/kernfs/filesystem.go | 10 +++++----- pkg/sentry/fsimpl/kernfs/inode_impl_util.go | 6 +++--- pkg/sentry/fsimpl/kernfs/kernfs.go | 2 +- pkg/sentry/fsimpl/kernfs/kernfs_test.go | 8 ++++---- pkg/sentry/fsimpl/proc/subtasks.go | 4 ++-- pkg/sentry/fsimpl/proc/task.go | 4 ++-- pkg/sentry/fsimpl/proc/tasks.go | 4 ++-- pkg/sentry/fsimpl/sys/sys.go | 4 ++-- pkg/sentry/fsimpl/tmpfs/filesystem.go | 2 +- pkg/sentry/vfs/options.go | 5 +++++ pkg/sentry/vfs/permissions.go | 19 ++++++++++++------- pkg/sentry/vfs/vfs.go | 19 +++++++++++++++++++ 17 files changed, 82 insertions(+), 53 deletions(-) (limited to 'pkg/sentry/fsimpl/tmpfs/filesystem.go') diff --git a/pkg/sentry/fsimpl/ext/filesystem.go b/pkg/sentry/fsimpl/ext/filesystem.go index 07bf58953..e05429d41 100644 --- a/pkg/sentry/fsimpl/ext/filesystem.go +++ b/pkg/sentry/fsimpl/ext/filesystem.go @@ -296,7 +296,7 @@ func (fs *filesystem) OpenAt(ctx context.Context, rp *vfs.ResolvingPath, opts vf if vfs.MayWriteFileWithOpenFlags(opts.Flags) || opts.Flags&(linux.O_CREAT|linux.O_EXCL|linux.O_TMPFILE) != 0 { return nil, syserror.EROFS } - return inode.open(rp, vfsd, opts.Flags) + return inode.open(rp, vfsd, &opts) } // ReadlinkAt implements vfs.FilesystemImpl.ReadlinkAt. diff --git a/pkg/sentry/fsimpl/ext/inode.go b/pkg/sentry/fsimpl/ext/inode.go index 191b39970..6962083f5 100644 --- a/pkg/sentry/fsimpl/ext/inode.go +++ b/pkg/sentry/fsimpl/ext/inode.go @@ -148,8 +148,8 @@ func newInode(fs *filesystem, inodeNum uint32) (*inode, error) { } // open creates and returns a file description for the dentry passed in. -func (in *inode) open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, flags uint32) (*vfs.FileDescription, error) { - ats := vfs.AccessTypesForOpenFlags(flags) +func (in *inode) open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts *vfs.OpenOptions) (*vfs.FileDescription, error) { + ats := vfs.AccessTypesForOpenFlags(opts) if err := in.checkPermissions(rp.Credentials(), ats); err != nil { return nil, err } @@ -157,7 +157,7 @@ func (in *inode) open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, flags uint32) (*v switch in.impl.(type) { case *regularFile: var fd regularFileFD - if err := fd.vfsfd.Init(&fd, flags, mnt, vfsd, &vfs.FileDescriptionOptions{}); err != nil { + if err := fd.vfsfd.Init(&fd, opts.Flags, mnt, vfsd, &vfs.FileDescriptionOptions{}); err != nil { return nil, err } return &fd.vfsfd, nil @@ -168,17 +168,17 @@ func (in *inode) open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, flags uint32) (*v return nil, syserror.EISDIR } var fd directoryFD - if err := fd.vfsfd.Init(&fd, flags, mnt, vfsd, &vfs.FileDescriptionOptions{}); err != nil { + if err := fd.vfsfd.Init(&fd, opts.Flags, mnt, vfsd, &vfs.FileDescriptionOptions{}); err != nil { return nil, err } return &fd.vfsfd, nil case *symlink: - if flags&linux.O_PATH == 0 { + if opts.Flags&linux.O_PATH == 0 { // Can't open symlinks without O_PATH. return nil, syserror.ELOOP } var fd symlinkFD - fd.vfsfd.Init(&fd, flags, mnt, vfsd, &vfs.FileDescriptionOptions{}) + fd.vfsfd.Init(&fd, opts.Flags, mnt, vfsd, &vfs.FileDescriptionOptions{}) return &fd.vfsfd, nil default: panic(fmt.Sprintf("unknown inode type: %T", in.impl)) diff --git a/pkg/sentry/fsimpl/gofer/filesystem.go b/pkg/sentry/fsimpl/gofer/filesystem.go index 8eb61debf..138adb9f7 100644 --- a/pkg/sentry/fsimpl/gofer/filesystem.go +++ b/pkg/sentry/fsimpl/gofer/filesystem.go @@ -593,7 +593,7 @@ func (fs *filesystem) OpenAt(ctx context.Context, rp *vfs.ResolvingPath, opts vf } } if rp.Done() { - return start.openLocked(ctx, rp, opts.Flags) + return start.openLocked(ctx, rp, &opts) } afterTrailingSymlink: @@ -633,12 +633,12 @@ afterTrailingSymlink: start = parent goto afterTrailingSymlink } - return child.openLocked(ctx, rp, opts.Flags) + return child.openLocked(ctx, rp, &opts) } // Preconditions: fs.renameMu must be locked. -func (d *dentry) openLocked(ctx context.Context, rp *vfs.ResolvingPath, flags uint32) (*vfs.FileDescription, error) { - ats := vfs.AccessTypesForOpenFlags(flags) +func (d *dentry) openLocked(ctx context.Context, rp *vfs.ResolvingPath, opts *vfs.OpenOptions) (*vfs.FileDescription, error) { + ats := vfs.AccessTypesForOpenFlags(opts) if err := d.checkPermissions(rp.Credentials(), ats, d.isDir()); err != nil { return nil, err } @@ -646,11 +646,11 @@ func (d *dentry) openLocked(ctx context.Context, rp *vfs.ResolvingPath, flags ui filetype := d.fileType() switch { case filetype == linux.S_IFREG && !d.fs.opts.regularFilesUseSpecialFileFD: - if err := d.ensureSharedHandle(ctx, ats&vfs.MayRead != 0, ats&vfs.MayWrite != 0, flags&linux.O_TRUNC != 0); err != nil { + if err := d.ensureSharedHandle(ctx, ats&vfs.MayRead != 0, ats&vfs.MayWrite != 0, opts.Flags&linux.O_TRUNC != 0); err != nil { return nil, err } fd := ®ularFileFD{} - if err := fd.vfsfd.Init(fd, flags, mnt, &d.vfsd, &vfs.FileDescriptionOptions{ + if err := fd.vfsfd.Init(fd, opts.Flags, mnt, &d.vfsd, &vfs.FileDescriptionOptions{ AllowDirectIO: true, }); err != nil { return nil, err @@ -658,21 +658,21 @@ func (d *dentry) openLocked(ctx context.Context, rp *vfs.ResolvingPath, flags ui return &fd.vfsfd, nil case filetype == linux.S_IFDIR: // Can't open directories with O_CREAT. - if flags&linux.O_CREAT != 0 { + if opts.Flags&linux.O_CREAT != 0 { return nil, syserror.EISDIR } // Can't open directories writably. if ats&vfs.MayWrite != 0 { return nil, syserror.EISDIR } - if flags&linux.O_DIRECT != 0 { + if opts.Flags&linux.O_DIRECT != 0 { return nil, syserror.EINVAL } if err := d.ensureSharedHandle(ctx, ats&vfs.MayRead != 0, false /* write */, false /* trunc */); err != nil { return nil, err } fd := &directoryFD{} - if err := fd.vfsfd.Init(fd, flags, mnt, &d.vfsd, &vfs.FileDescriptionOptions{}); err != nil { + if err := fd.vfsfd.Init(fd, opts.Flags, mnt, &d.vfsd, &vfs.FileDescriptionOptions{}); err != nil { return nil, err } return &fd.vfsfd, nil @@ -680,17 +680,17 @@ func (d *dentry) openLocked(ctx context.Context, rp *vfs.ResolvingPath, flags ui // Can't open symlinks without O_PATH (which is unimplemented). return nil, syserror.ELOOP default: - if flags&linux.O_DIRECT != 0 { + if opts.Flags&linux.O_DIRECT != 0 { return nil, syserror.EINVAL } - h, err := openHandle(ctx, d.file, ats&vfs.MayRead != 0, ats&vfs.MayWrite != 0, flags&linux.O_TRUNC != 0) + h, err := openHandle(ctx, d.file, ats&vfs.MayRead != 0, ats&vfs.MayWrite != 0, opts.Flags&linux.O_TRUNC != 0) if err != nil { return nil, err } fd := &specialFileFD{ handle: h, } - if err := fd.vfsfd.Init(fd, flags, mnt, &d.vfsd, &vfs.FileDescriptionOptions{}); err != nil { + if err := fd.vfsfd.Init(fd, opts.Flags, mnt, &d.vfsd, &vfs.FileDescriptionOptions{}); err != nil { h.close(ctx) return nil, err } diff --git a/pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go b/pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go index 733792c78..d092ccb2a 100644 --- a/pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go +++ b/pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go @@ -53,9 +53,9 @@ func (f *DynamicBytesFile) Init(creds *auth.Credentials, ino uint64, data vfs.Dy } // Open implements Inode.Open. -func (f *DynamicBytesFile) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, flags uint32) (*vfs.FileDescription, error) { +func (f *DynamicBytesFile) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) { fd := &DynamicBytesFD{} - if err := fd.Init(rp.Mount(), vfsd, f.data, flags); err != nil { + if err := fd.Init(rp.Mount(), vfsd, f.data, opts.Flags); err != nil { return nil, err } return &fd.vfsfd, nil diff --git a/pkg/sentry/fsimpl/kernfs/fd_impl_util.go b/pkg/sentry/fsimpl/kernfs/fd_impl_util.go index 6104751c8..eda781155 100644 --- a/pkg/sentry/fsimpl/kernfs/fd_impl_util.go +++ b/pkg/sentry/fsimpl/kernfs/fd_impl_util.go @@ -43,12 +43,12 @@ type GenericDirectoryFD struct { } // Init initializes a GenericDirectoryFD. -func (fd *GenericDirectoryFD) Init(m *vfs.Mount, d *vfs.Dentry, children *OrderedChildren, flags uint32) error { - if vfs.AccessTypesForOpenFlags(flags)&vfs.MayWrite != 0 { +func (fd *GenericDirectoryFD) Init(m *vfs.Mount, d *vfs.Dentry, children *OrderedChildren, opts *vfs.OpenOptions) error { + if vfs.AccessTypesForOpenFlags(opts)&vfs.MayWrite != 0 { // Can't open directories for writing. return syserror.EISDIR } - if err := fd.vfsfd.Init(fd, flags, m, d, &vfs.FileDescriptionOptions{}); err != nil { + if err := fd.vfsfd.Init(fd, opts.Flags, m, d, &vfs.FileDescriptionOptions{}); err != nil { return err } fd.children = children diff --git a/pkg/sentry/fsimpl/kernfs/filesystem.go b/pkg/sentry/fsimpl/kernfs/filesystem.go index e49303c26..ee98eb66a 100644 --- a/pkg/sentry/fsimpl/kernfs/filesystem.go +++ b/pkg/sentry/fsimpl/kernfs/filesystem.go @@ -365,7 +365,7 @@ func (fs *Filesystem) OpenAt(ctx context.Context, rp *vfs.ResolvingPath, opts vf // appropriate bits in rp), but are returned by // FileDescriptionImpl.StatusFlags(). opts.Flags &= linux.O_ACCMODE | linux.O_CREAT | linux.O_EXCL | linux.O_TRUNC | linux.O_DIRECTORY | linux.O_NOFOLLOW - ats := vfs.AccessTypesForOpenFlags(opts.Flags) + ats := vfs.AccessTypesForOpenFlags(&opts) // Do not create new file. if opts.Flags&linux.O_CREAT == 0 { @@ -379,7 +379,7 @@ func (fs *Filesystem) OpenAt(ctx context.Context, rp *vfs.ResolvingPath, opts vf if err := inode.CheckPermissions(ctx, rp.Credentials(), ats); err != nil { return nil, err } - return inode.Open(rp, vfsd, opts.Flags) + return inode.Open(rp, vfsd, opts) } // May create new file. @@ -398,7 +398,7 @@ func (fs *Filesystem) OpenAt(ctx context.Context, rp *vfs.ResolvingPath, opts vf if err := inode.CheckPermissions(ctx, rp.Credentials(), ats); err != nil { return nil, err } - return inode.Open(rp, vfsd, opts.Flags) + return inode.Open(rp, vfsd, opts) } afterTrailingSymlink: parentVFSD, parentInode, err := fs.walkParentDirLocked(ctx, rp) @@ -438,7 +438,7 @@ afterTrailingSymlink: return nil, err } parentVFSD.Impl().(*Dentry).InsertChild(pc, child) - return child.Impl().(*Dentry).inode.Open(rp, child, opts.Flags) + return child.Impl().(*Dentry).inode.Open(rp, child, opts) } // Open existing file or follow symlink. if mustCreate { @@ -463,7 +463,7 @@ afterTrailingSymlink: if err := childInode.CheckPermissions(ctx, rp.Credentials(), ats); err != nil { return nil, err } - return childInode.Open(rp, childVFSD, opts.Flags) + return childInode.Open(rp, childVFSD, opts) } // ReadlinkAt implements vfs.FilesystemImpl.ReadlinkAt. diff --git a/pkg/sentry/fsimpl/kernfs/inode_impl_util.go b/pkg/sentry/fsimpl/kernfs/inode_impl_util.go index adca2313f..099d70a16 100644 --- a/pkg/sentry/fsimpl/kernfs/inode_impl_util.go +++ b/pkg/sentry/fsimpl/kernfs/inode_impl_util.go @@ -507,7 +507,7 @@ type InodeSymlink struct { } // Open implements Inode.Open. -func (InodeSymlink) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, flags uint32) (*vfs.FileDescription, error) { +func (InodeSymlink) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) { return nil, syserror.ELOOP } @@ -549,8 +549,8 @@ func (s *StaticDirectory) Init(creds *auth.Credentials, ino uint64, perm linux.F } // Open implements kernfs.Inode. -func (s *StaticDirectory) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, flags uint32) (*vfs.FileDescription, error) { +func (s *StaticDirectory) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) { fd := &GenericDirectoryFD{} - fd.Init(rp.Mount(), vfsd, &s.OrderedChildren, flags) + fd.Init(rp.Mount(), vfsd, &s.OrderedChildren, &opts) return fd.VFSFileDescription(), nil } diff --git a/pkg/sentry/fsimpl/kernfs/kernfs.go b/pkg/sentry/fsimpl/kernfs/kernfs.go index 79ebea8a5..c74fa999b 100644 --- a/pkg/sentry/fsimpl/kernfs/kernfs.go +++ b/pkg/sentry/fsimpl/kernfs/kernfs.go @@ -303,7 +303,7 @@ type Inode interface { // inode for its lifetime. // // Precondition: !rp.Done(). vfsd.Impl() must be a kernfs Dentry. - Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, flags uint32) (*vfs.FileDescription, error) + Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) } type inodeRefs interface { diff --git a/pkg/sentry/fsimpl/kernfs/kernfs_test.go b/pkg/sentry/fsimpl/kernfs/kernfs_test.go index ee65cf491..96a16e654 100644 --- a/pkg/sentry/fsimpl/kernfs/kernfs_test.go +++ b/pkg/sentry/fsimpl/kernfs/kernfs_test.go @@ -113,9 +113,9 @@ func (fs *filesystem) newReadonlyDir(creds *auth.Credentials, mode linux.FileMod return &dir.dentry } -func (d *readonlyDir) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, flags uint32) (*vfs.FileDescription, error) { +func (d *readonlyDir) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) { fd := &kernfs.GenericDirectoryFD{} - if err := fd.Init(rp.Mount(), vfsd, &d.OrderedChildren, flags); err != nil { + if err := fd.Init(rp.Mount(), vfsd, &d.OrderedChildren, &opts); err != nil { return nil, err } return fd.VFSFileDescription(), nil @@ -143,9 +143,9 @@ func (fs *filesystem) newDir(creds *auth.Credentials, mode linux.FileMode, conte return &dir.dentry } -func (d *dir) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, flags uint32) (*vfs.FileDescription, error) { +func (d *dir) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) { fd := &kernfs.GenericDirectoryFD{} - fd.Init(rp.Mount(), vfsd, &d.OrderedChildren, flags) + fd.Init(rp.Mount(), vfsd, &d.OrderedChildren, &opts) return fd.VFSFileDescription(), nil } diff --git a/pkg/sentry/fsimpl/proc/subtasks.go b/pkg/sentry/fsimpl/proc/subtasks.go index 353e37195..102af0e93 100644 --- a/pkg/sentry/fsimpl/proc/subtasks.go +++ b/pkg/sentry/fsimpl/proc/subtasks.go @@ -114,9 +114,9 @@ func (i *subtasksInode) IterDirents(ctx context.Context, cb vfs.IterDirentsCallb } // Open implements kernfs.Inode. -func (i *subtasksInode) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, flags uint32) (*vfs.FileDescription, error) { +func (i *subtasksInode) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) { fd := &kernfs.GenericDirectoryFD{} - fd.Init(rp.Mount(), vfsd, &i.OrderedChildren, flags) + fd.Init(rp.Mount(), vfsd, &i.OrderedChildren, &opts) return fd.VFSFileDescription(), nil } diff --git a/pkg/sentry/fsimpl/proc/task.go b/pkg/sentry/fsimpl/proc/task.go index eb5bc62c0..2d814668a 100644 --- a/pkg/sentry/fsimpl/proc/task.go +++ b/pkg/sentry/fsimpl/proc/task.go @@ -98,9 +98,9 @@ func (i *taskInode) Valid(ctx context.Context) bool { } // Open implements kernfs.Inode. -func (i *taskInode) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, flags uint32) (*vfs.FileDescription, error) { +func (i *taskInode) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) { fd := &kernfs.GenericDirectoryFD{} - fd.Init(rp.Mount(), vfsd, &i.OrderedChildren, flags) + fd.Init(rp.Mount(), vfsd, &i.OrderedChildren, &opts) return fd.VFSFileDescription(), nil } diff --git a/pkg/sentry/fsimpl/proc/tasks.go b/pkg/sentry/fsimpl/proc/tasks.go index 14bd334e8..ebe21630c 100644 --- a/pkg/sentry/fsimpl/proc/tasks.go +++ b/pkg/sentry/fsimpl/proc/tasks.go @@ -205,9 +205,9 @@ func (i *tasksInode) IterDirents(ctx context.Context, cb vfs.IterDirentsCallback } // Open implements kernfs.Inode. -func (i *tasksInode) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, flags uint32) (*vfs.FileDescription, error) { +func (i *tasksInode) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) { fd := &kernfs.GenericDirectoryFD{} - fd.Init(rp.Mount(), vfsd, &i.OrderedChildren, flags) + fd.Init(rp.Mount(), vfsd, &i.OrderedChildren, &opts) return fd.VFSFileDescription(), nil } diff --git a/pkg/sentry/fsimpl/sys/sys.go b/pkg/sentry/fsimpl/sys/sys.go index e35d52d17..d693fceae 100644 --- a/pkg/sentry/fsimpl/sys/sys.go +++ b/pkg/sentry/fsimpl/sys/sys.go @@ -97,9 +97,9 @@ func (d *dir) SetStat(fs *vfs.Filesystem, opts vfs.SetStatOptions) error { } // Open implements kernfs.Inode.Open. -func (d *dir) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, flags uint32) (*vfs.FileDescription, error) { +func (d *dir) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) { fd := &kernfs.GenericDirectoryFD{} - fd.Init(rp.Mount(), vfsd, &d.OrderedChildren, flags) + fd.Init(rp.Mount(), vfsd, &d.OrderedChildren, &opts) return fd.VFSFileDescription(), nil } diff --git a/pkg/sentry/fsimpl/tmpfs/filesystem.go b/pkg/sentry/fsimpl/tmpfs/filesystem.go index 72bc15264..8785452b6 100644 --- a/pkg/sentry/fsimpl/tmpfs/filesystem.go +++ b/pkg/sentry/fsimpl/tmpfs/filesystem.go @@ -334,7 +334,7 @@ afterTrailingSymlink: } func (d *dentry) open(ctx context.Context, rp *vfs.ResolvingPath, opts *vfs.OpenOptions, afterCreate bool) (*vfs.FileDescription, error) { - ats := vfs.AccessTypesForOpenFlags(opts.Flags) + ats := vfs.AccessTypesForOpenFlags(opts) if !afterCreate { if err := d.inode.checkPermissions(rp.Credentials(), ats, d.inode.isDir()); err != nil { return nil, err diff --git a/pkg/sentry/vfs/options.go b/pkg/sentry/vfs/options.go index b7774bf28..fdf8be157 100644 --- a/pkg/sentry/vfs/options.go +++ b/pkg/sentry/vfs/options.go @@ -72,6 +72,11 @@ type OpenOptions struct { // If FilesystemImpl.OpenAt() creates a file, Mode is the file mode for the // created file. Mode linux.FileMode + + // FileExec is set when the file is being opened to be executed. + // VirtualFilesystem.OpenAt() checks that the caller has execute permissions + // on the file, and that the file is a regular file. + FileExec bool } // ReadOptions contains options to FileDescription.PRead(), diff --git a/pkg/sentry/vfs/permissions.go b/pkg/sentry/vfs/permissions.go index f664581f4..8e250998a 100644 --- a/pkg/sentry/vfs/permissions.go +++ b/pkg/sentry/vfs/permissions.go @@ -103,17 +103,22 @@ func GenericCheckPermissions(creds *auth.Credentials, ats AccessTypes, isDir boo // AccessTypesForOpenFlags returns MayRead|MayWrite in this case. // // Use May{Read,Write}FileWithOpenFlags() for these checks instead. -func AccessTypesForOpenFlags(flags uint32) AccessTypes { - switch flags & linux.O_ACCMODE { +func AccessTypesForOpenFlags(opts *OpenOptions) AccessTypes { + ats := AccessTypes(0) + if opts.FileExec { + ats |= MayExec + } + + switch opts.Flags & linux.O_ACCMODE { case linux.O_RDONLY: - if flags&linux.O_TRUNC != 0 { - return MayRead | MayWrite + if opts.Flags&linux.O_TRUNC != 0 { + return ats | MayRead | MayWrite } - return MayRead + return ats | MayRead case linux.O_WRONLY: - return MayWrite + return ats | MayWrite default: - return MayRead | MayWrite + return ats | MayRead | MayWrite } } diff --git a/pkg/sentry/vfs/vfs.go b/pkg/sentry/vfs/vfs.go index 908c69f91..9629afee9 100644 --- a/pkg/sentry/vfs/vfs.go +++ b/pkg/sentry/vfs/vfs.go @@ -379,6 +379,25 @@ func (vfs *VirtualFilesystem) OpenAt(ctx context.Context, creds *auth.Credential fd, err := rp.mount.fs.impl.OpenAt(ctx, rp, *opts) if err == nil { vfs.putResolvingPath(rp) + + // TODO(gvisor.dev/issue/1193): Move inside fsimpl to avoid another call + // to FileDescription.Stat(). + if opts.FileExec { + // Only a regular file can be executed. + stat, err := fd.Stat(ctx, StatOptions{Mask: linux.STATX_TYPE}) + if err != nil { + return nil, err + } + if stat.Mask&linux.STATX_TYPE != 0 { + // This shouldn't happen, but if type can't be retrieved, file can't + // be executed. + return nil, syserror.EACCES + } + if linux.FileMode(stat.Mode).FileType() != linux.ModeRegular { + return nil, syserror.EACCES + } + } + return fd, nil } if !rp.handleError(err) { -- cgit v1.2.3 From 4075de11be44372c454aae7f9650cdc814c52229 Mon Sep 17 00:00:00 2001 From: gVisor bot Date: Fri, 14 Feb 2020 11:11:55 -0800 Subject: Plumb VFS2 inside the Sentry - Added fsbridge package with interface that can be used to open and read from VFS1 and VFS2 files. - Converted ELF loader to use fsbridge - Added VFS2 types to FSContext - Added vfs.MountNamespace to ThreadGroup Updates #1623 PiperOrigin-RevId: 295183950 --- pkg/sentry/control/BUILD | 5 + pkg/sentry/control/proc.go | 127 +++++++++++++-- pkg/sentry/fs/proc/BUILD | 1 + pkg/sentry/fs/proc/task.go | 17 +- pkg/sentry/fsbridge/BUILD | 24 +++ pkg/sentry/fsbridge/bridge.go | 54 ++++++ pkg/sentry/fsbridge/fs.go | 181 +++++++++++++++++++++ pkg/sentry/fsbridge/vfs.go | 134 +++++++++++++++ pkg/sentry/fsimpl/devtmpfs/devtmpfs.go | 4 + pkg/sentry/fsimpl/gofer/filesystem.go | 5 +- pkg/sentry/fsimpl/gofer/gofer.go | 3 + pkg/sentry/fsimpl/kernfs/filesystem.go | 10 +- pkg/sentry/fsimpl/proc/BUILD | 1 + pkg/sentry/fsimpl/proc/filesystem.go | 18 +- pkg/sentry/fsimpl/proc/tasks_test.go | 17 +- pkg/sentry/fsimpl/sys/BUILD | 1 + pkg/sentry/fsimpl/sys/sys.go | 3 + pkg/sentry/fsimpl/sys/sys_test.go | 7 +- pkg/sentry/fsimpl/testutil/BUILD | 2 +- pkg/sentry/fsimpl/testutil/kernel.go | 24 +-- pkg/sentry/fsimpl/testutil/testutil.go | 12 +- pkg/sentry/fsimpl/tmpfs/filesystem.go | 12 +- pkg/sentry/fsimpl/tmpfs/tmpfs.go | 3 + pkg/sentry/kernel/BUILD | 2 + pkg/sentry/kernel/fs_context.go | 98 +++++++++-- pkg/sentry/kernel/kernel.go | 145 +++++++++++++---- pkg/sentry/kernel/task.go | 27 +++ pkg/sentry/kernel/task_clone.go | 11 +- pkg/sentry/kernel/task_context.go | 2 +- pkg/sentry/kernel/task_exit.go | 7 + pkg/sentry/kernel/task_log.go | 15 +- pkg/sentry/kernel/task_start.go | 49 +++--- pkg/sentry/kernel/thread_group.go | 6 +- pkg/sentry/loader/BUILD | 2 + pkg/sentry/loader/elf.go | 28 ++-- pkg/sentry/loader/interpreter.go | 6 +- pkg/sentry/loader/loader.go | 179 ++++++-------------- pkg/sentry/loader/vdso.go | 7 +- pkg/sentry/mm/BUILD | 2 +- pkg/sentry/mm/metadata.go | 10 +- pkg/sentry/mm/mm.go | 4 +- pkg/sentry/strace/strace.go | 28 ++++ pkg/sentry/syscalls/linux/BUILD | 1 + pkg/sentry/syscalls/linux/sys_prctl.go | 3 +- pkg/sentry/syscalls/linux/sys_thread.go | 17 +- .../syscalls/linux/vfs2/linux64_override_amd64.go | 106 ++++++++++++ pkg/sentry/vfs/BUILD | 1 + pkg/sentry/vfs/context.go | 7 +- pkg/sentry/vfs/mount.go | 10 +- pkg/sentry/vfs/options.go | 2 +- pkg/sentry/vfs/vfs.go | 5 +- runsc/boot/loader.go | 11 +- 52 files changed, 1134 insertions(+), 322 deletions(-) create mode 100644 pkg/sentry/fsbridge/BUILD create mode 100644 pkg/sentry/fsbridge/bridge.go create mode 100644 pkg/sentry/fsbridge/fs.go create mode 100644 pkg/sentry/fsbridge/vfs.go (limited to 'pkg/sentry/fsimpl/tmpfs/filesystem.go') diff --git a/pkg/sentry/control/BUILD b/pkg/sentry/control/BUILD index e69496477..d16d78aa5 100644 --- a/pkg/sentry/control/BUILD +++ b/pkg/sentry/control/BUILD @@ -16,10 +16,13 @@ go_library( ], deps = [ "//pkg/abi/linux", + "//pkg/context", "//pkg/fd", + "//pkg/fspath", "//pkg/log", "//pkg/sentry/fs", "//pkg/sentry/fs/host", + "//pkg/sentry/fsbridge", "//pkg/sentry/kernel", "//pkg/sentry/kernel/auth", "//pkg/sentry/kernel/time", @@ -27,8 +30,10 @@ go_library( "//pkg/sentry/state", "//pkg/sentry/strace", "//pkg/sentry/usage", + "//pkg/sentry/vfs", "//pkg/sentry/watchdog", "//pkg/sync", + "//pkg/syserror", "//pkg/tcpip/link/sniffer", "//pkg/urpc", ], diff --git a/pkg/sentry/control/proc.go b/pkg/sentry/control/proc.go index ced51c66c..8973754c8 100644 --- a/pkg/sentry/control/proc.go +++ b/pkg/sentry/control/proc.go @@ -18,19 +18,26 @@ import ( "bytes" "encoding/json" "fmt" + "path" "sort" "strings" "text/tabwriter" "time" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/fspath" + "gvisor.dev/gvisor/pkg/log" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/host" + "gvisor.dev/gvisor/pkg/sentry/fsbridge" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/limits" "gvisor.dev/gvisor/pkg/sentry/usage" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/urpc" ) @@ -60,6 +67,12 @@ type ExecArgs struct { // process's MountNamespace. MountNamespace *fs.MountNamespace + // MountNamespaceVFS2 is the mount namespace to execute the new process in. + // A reference on MountNamespace must be held for the lifetime of the + // ExecArgs. If MountNamespace is nil, it will default to the init + // process's MountNamespace. + MountNamespaceVFS2 *vfs.MountNamespace + // WorkingDirectory defines the working directory for the new process. WorkingDirectory string `json:"wd"` @@ -150,6 +163,7 @@ func (proc *Proc) execAsync(args *ExecArgs) (*kernel.ThreadGroup, kernel.ThreadI Envv: args.Envv, WorkingDirectory: args.WorkingDirectory, MountNamespace: args.MountNamespace, + MountNamespaceVFS2: args.MountNamespaceVFS2, Credentials: creds, FDTable: fdTable, Umask: 0022, @@ -166,24 +180,53 @@ func (proc *Proc) execAsync(args *ExecArgs) (*kernel.ThreadGroup, kernel.ThreadI // be donated to the new process in CreateProcess. initArgs.MountNamespace.IncRef() } + if initArgs.MountNamespaceVFS2 != nil { + // initArgs must hold a reference on MountNamespaceVFS2, which will + // be donated to the new process in CreateProcess. + initArgs.MountNamespaceVFS2.IncRef() + } ctx := initArgs.NewContext(proc.Kernel) if initArgs.Filename == "" { - // Get the full path to the filename from the PATH env variable. - paths := fs.GetPath(initArgs.Envv) - mns := initArgs.MountNamespace - if mns == nil { - mns = proc.Kernel.GlobalInit().Leader().MountNamespace() - } - f, err := mns.ResolveExecutablePath(ctx, initArgs.WorkingDirectory, initArgs.Argv[0], paths) - if err != nil { - return nil, 0, nil, fmt.Errorf("error finding executable %q in PATH %v: %v", initArgs.Argv[0], paths, err) + if kernel.VFS2Enabled { + // Get the full path to the filename from the PATH env variable. + if initArgs.MountNamespaceVFS2 == nil { + // Set initArgs so that 'ctx' returns the namespace. + // + // MountNamespaceVFS2 adds a reference to the namespace, which is + // transferred to the new process. + initArgs.MountNamespaceVFS2 = proc.Kernel.GlobalInit().Leader().MountNamespaceVFS2() + } + + paths := fs.GetPath(initArgs.Envv) + vfsObj := proc.Kernel.VFS + file, err := ResolveExecutablePath(ctx, vfsObj, initArgs.WorkingDirectory, initArgs.Argv[0], paths) + if err != nil { + return nil, 0, nil, fmt.Errorf("error finding executable %q in PATH %v: %v", initArgs.Argv[0], paths, err) + } + initArgs.File = fsbridge.NewVFSFile(file) + } else { + // Get the full path to the filename from the PATH env variable. + paths := fs.GetPath(initArgs.Envv) + if initArgs.MountNamespace == nil { + // Set initArgs so that 'ctx' returns the namespace. + initArgs.MountNamespace = proc.Kernel.GlobalInit().Leader().MountNamespace() + + // initArgs must hold a reference on MountNamespace, which will + // be donated to the new process in CreateProcess. + initArgs.MountNamespaceVFS2.IncRef() + } + f, err := initArgs.MountNamespace.ResolveExecutablePath(ctx, initArgs.WorkingDirectory, initArgs.Argv[0], paths) + if err != nil { + return nil, 0, nil, fmt.Errorf("error finding executable %q in PATH %v: %v", initArgs.Argv[0], paths, err) + } + initArgs.Filename = f } - initArgs.Filename = f } mounter := fs.FileOwnerFromContext(ctx) + // TODO(gvisor.dev/issue/1623): Use host FD when supported in VFS2. var ttyFile *fs.File for appFD, hostFile := range args.FilePayload.Files { var appFile *fs.File @@ -411,3 +454,67 @@ func ttyName(tty *kernel.TTY) string { } return fmt.Sprintf("pts/%d", tty.Index) } + +// ResolveExecutablePath resolves the given executable name given a set of +// paths that might contain it. +func ResolveExecutablePath(ctx context.Context, vfsObj *vfs.VirtualFilesystem, wd, name string, paths []string) (*vfs.FileDescription, error) { + root := vfs.RootFromContext(ctx) + defer root.DecRef() + creds := auth.CredentialsFromContext(ctx) + + // Absolute paths can be used directly. + if path.IsAbs(name) { + return openExecutable(ctx, vfsObj, creds, root, name) + } + + // Paths with '/' in them should be joined to the working directory, or + // to the root if working directory is not set. + if strings.IndexByte(name, '/') > 0 { + if len(wd) == 0 { + wd = "/" + } + if !path.IsAbs(wd) { + return nil, fmt.Errorf("working directory %q must be absolute", wd) + } + return openExecutable(ctx, vfsObj, creds, root, path.Join(wd, name)) + } + + // Otherwise, we must lookup the name in the paths, starting from the + // calling context's root directory. + for _, p := range paths { + if !path.IsAbs(p) { + // Relative paths aren't safe, no one should be using them. + log.Warningf("Skipping relative path %q in $PATH", p) + continue + } + + binPath := path.Join(p, name) + f, err := openExecutable(ctx, vfsObj, creds, root, binPath) + if err != nil { + return nil, err + } + if f == nil { + continue // Not found/no access. + } + return f, nil + } + return nil, syserror.ENOENT +} + +func openExecutable(ctx context.Context, vfsObj *vfs.VirtualFilesystem, creds *auth.Credentials, root vfs.VirtualDentry, path string) (*vfs.FileDescription, error) { + pop := vfs.PathOperation{ + Root: root, + Start: root, // binPath is absolute, Start can be anything. + Path: fspath.Parse(path), + FollowFinalSymlink: true, + } + opts := &vfs.OpenOptions{ + Flags: linux.O_RDONLY, + FileExec: true, + } + f, err := vfsObj.OpenAt(ctx, creds, &pop, opts) + if err == syserror.ENOENT || err == syserror.EACCES { + return nil, nil + } + return f, err +} diff --git a/pkg/sentry/fs/proc/BUILD b/pkg/sentry/fs/proc/BUILD index 280093c5e..77c2c5c0e 100644 --- a/pkg/sentry/fs/proc/BUILD +++ b/pkg/sentry/fs/proc/BUILD @@ -36,6 +36,7 @@ go_library( "//pkg/sentry/fs/proc/device", "//pkg/sentry/fs/proc/seqfile", "//pkg/sentry/fs/ramfs", + "//pkg/sentry/fsbridge", "//pkg/sentry/inet", "//pkg/sentry/kernel", "//pkg/sentry/kernel/auth", diff --git a/pkg/sentry/fs/proc/task.go b/pkg/sentry/fs/proc/task.go index ca020e11e..8ab8d8a02 100644 --- a/pkg/sentry/fs/proc/task.go +++ b/pkg/sentry/fs/proc/task.go @@ -28,6 +28,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/fs/proc/device" "gvisor.dev/gvisor/pkg/sentry/fs/proc/seqfile" "gvisor.dev/gvisor/pkg/sentry/fs/ramfs" + "gvisor.dev/gvisor/pkg/sentry/fsbridge" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/limits" "gvisor.dev/gvisor/pkg/sentry/mm" @@ -249,7 +250,7 @@ func newExe(t *kernel.Task, msrc *fs.MountSource) *fs.Inode { return newProcInode(t, exeSymlink, msrc, fs.Symlink, t) } -func (e *exe) executable() (d *fs.Dirent, err error) { +func (e *exe) executable() (file fsbridge.File, err error) { e.t.WithMuLocked(func(t *kernel.Task) { mm := t.MemoryManager() if mm == nil { @@ -262,8 +263,8 @@ func (e *exe) executable() (d *fs.Dirent, err error) { // The MemoryManager may be destroyed, in which case // MemoryManager.destroy will simply set the executable to nil // (with locks held). - d = mm.Executable() - if d == nil { + file = mm.Executable() + if file == nil { err = syserror.ENOENT } }) @@ -283,15 +284,7 @@ func (e *exe) Readlink(ctx context.Context, inode *fs.Inode) (string, error) { } defer exec.DecRef() - root := fs.RootFromContext(ctx) - if root == nil { - // This doesn't correspond to anything in Linux because the vfs is - // global there. - return "", syserror.EINVAL - } - defer root.DecRef() - n, _ := exec.FullName(root) - return n, nil + return exec.PathnameWithDeleted(ctx), nil } // namespaceSymlink represents a symlink in the namespacefs, such as the files diff --git a/pkg/sentry/fsbridge/BUILD b/pkg/sentry/fsbridge/BUILD new file mode 100644 index 000000000..6c798f0bd --- /dev/null +++ b/pkg/sentry/fsbridge/BUILD @@ -0,0 +1,24 @@ +load("//tools:defs.bzl", "go_library") + +licenses(["notice"]) + +go_library( + name = "fsbridge", + srcs = [ + "bridge.go", + "fs.go", + "vfs.go", + ], + visibility = ["//pkg/sentry:internal"], + deps = [ + "//pkg/abi/linux", + "//pkg/context", + "//pkg/fspath", + "//pkg/sentry/fs", + "//pkg/sentry/kernel/auth", + "//pkg/sentry/memmap", + "//pkg/sentry/vfs", + "//pkg/syserror", + "//pkg/usermem", + ], +) diff --git a/pkg/sentry/fsbridge/bridge.go b/pkg/sentry/fsbridge/bridge.go new file mode 100644 index 000000000..8e7590721 --- /dev/null +++ b/pkg/sentry/fsbridge/bridge.go @@ -0,0 +1,54 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// Package fsbridge provides common interfaces to bridge between VFS1 and VFS2 +// files. +package fsbridge + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/sentry/memmap" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/usermem" +) + +// File provides a common interface to bridge between VFS1 and VFS2 files. +type File interface { + // PathnameWithDeleted returns an absolute pathname to vd, consistent with + // Linux's d_path(). In particular, if vd.Dentry() has been disowned, + // PathnameWithDeleted appends " (deleted)" to the returned pathname. + PathnameWithDeleted(ctx context.Context) string + + // ReadFull read all contents from the file. + ReadFull(ctx context.Context, dst usermem.IOSequence, offset int64) (int64, error) + + // ConfigureMMap mutates opts to implement mmap(2) for the file. + ConfigureMMap(context.Context, *memmap.MMapOpts) error + + // Type returns the file type, e.g. linux.S_IFREG. + Type(context.Context) (linux.FileMode, error) + + // IncRef increments reference. + IncRef() + + // DecRef decrements reference. + DecRef() +} + +// Lookup provides a common interface to open files. +type Lookup interface { + // OpenPath opens a file. + OpenPath(ctx context.Context, path string, opts vfs.OpenOptions, remainingTraversals *uint, resolveFinal bool) (File, error) +} diff --git a/pkg/sentry/fsbridge/fs.go b/pkg/sentry/fsbridge/fs.go new file mode 100644 index 000000000..093ce1fb3 --- /dev/null +++ b/pkg/sentry/fsbridge/fs.go @@ -0,0 +1,181 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package fsbridge + +import ( + "io" + "strings" + + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/sentry/fs" + "gvisor.dev/gvisor/pkg/sentry/memmap" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" +) + +// fsFile implements File interface over fs.File. +// +// +stateify savable +type fsFile struct { + file *fs.File +} + +var _ File = (*fsFile)(nil) + +// NewFSFile creates a new File over fs.File. +func NewFSFile(file *fs.File) File { + return &fsFile{file: file} +} + +// PathnameWithDeleted implements File. +func (f *fsFile) PathnameWithDeleted(ctx context.Context) string { + root := fs.RootFromContext(ctx) + if root == nil { + // This doesn't correspond to anything in Linux because the vfs is + // global there. + return "" + } + defer root.DecRef() + + name, _ := f.file.Dirent.FullName(root) + return name +} + +// ReadFull implements File. +func (f *fsFile) ReadFull(ctx context.Context, dst usermem.IOSequence, offset int64) (int64, error) { + var total int64 + for dst.NumBytes() > 0 { + n, err := f.file.Preadv(ctx, dst, offset+total) + total += n + if err == io.EOF && total != 0 { + return total, io.ErrUnexpectedEOF + } else if err != nil { + return total, err + } + dst = dst.DropFirst64(n) + } + return total, nil +} + +// ConfigureMMap implements File. +func (f *fsFile) ConfigureMMap(ctx context.Context, opts *memmap.MMapOpts) error { + return f.file.ConfigureMMap(ctx, opts) +} + +// Type implements File. +func (f *fsFile) Type(context.Context) (linux.FileMode, error) { + return linux.FileMode(f.file.Dirent.Inode.StableAttr.Type.LinuxType()), nil +} + +// IncRef implements File. +func (f *fsFile) IncRef() { + f.file.IncRef() +} + +// DecRef implements File. +func (f *fsFile) DecRef() { + f.file.DecRef() +} + +// fsLookup implements Lookup interface using fs.File. +// +// +stateify savable +type fsLookup struct { + mntns *fs.MountNamespace + + root *fs.Dirent + workingDir *fs.Dirent +} + +var _ Lookup = (*fsLookup)(nil) + +// NewFSLookup creates a new Lookup using VFS1. +func NewFSLookup(mntns *fs.MountNamespace, root, workingDir *fs.Dirent) Lookup { + return &fsLookup{ + mntns: mntns, + root: root, + workingDir: workingDir, + } +} + +// OpenPath implements Lookup. +func (l *fsLookup) OpenPath(ctx context.Context, path string, opts vfs.OpenOptions, remainingTraversals *uint, resolveFinal bool) (File, error) { + var d *fs.Dirent + var err error + if resolveFinal { + d, err = l.mntns.FindInode(ctx, l.root, l.workingDir, path, remainingTraversals) + } else { + d, err = l.mntns.FindLink(ctx, l.root, l.workingDir, path, remainingTraversals) + } + if err != nil { + return nil, err + } + defer d.DecRef() + + if !resolveFinal && fs.IsSymlink(d.Inode.StableAttr) { + return nil, syserror.ELOOP + } + + fsPerm := openOptionsToPermMask(&opts) + if err := d.Inode.CheckPermission(ctx, fsPerm); err != nil { + return nil, err + } + + // If they claim it's a directory, then make sure. + if strings.HasSuffix(path, "/") { + if d.Inode.StableAttr.Type != fs.Directory { + return nil, syserror.ENOTDIR + } + } + + if opts.FileExec && d.Inode.StableAttr.Type != fs.RegularFile { + ctx.Infof("%q is not a regular file: %v", path, d.Inode.StableAttr.Type) + return nil, syserror.EACCES + } + + f, err := d.Inode.GetFile(ctx, d, flagsToFileFlags(opts.Flags)) + if err != nil { + return nil, err + } + + return &fsFile{file: f}, nil +} + +func openOptionsToPermMask(opts *vfs.OpenOptions) fs.PermMask { + mode := opts.Flags & linux.O_ACCMODE + return fs.PermMask{ + Read: mode == linux.O_RDONLY || mode == linux.O_RDWR, + Write: mode == linux.O_WRONLY || mode == linux.O_RDWR, + Execute: opts.FileExec, + } +} + +func flagsToFileFlags(flags uint32) fs.FileFlags { + return fs.FileFlags{ + Direct: flags&linux.O_DIRECT != 0, + DSync: flags&(linux.O_DSYNC|linux.O_SYNC) != 0, + Sync: flags&linux.O_SYNC != 0, + NonBlocking: flags&linux.O_NONBLOCK != 0, + Read: (flags & linux.O_ACCMODE) != linux.O_WRONLY, + Write: (flags & linux.O_ACCMODE) != linux.O_RDONLY, + Append: flags&linux.O_APPEND != 0, + Directory: flags&linux.O_DIRECTORY != 0, + Async: flags&linux.O_ASYNC != 0, + LargeFile: flags&linux.O_LARGEFILE != 0, + Truncate: flags&linux.O_TRUNC != 0, + } +} diff --git a/pkg/sentry/fsbridge/vfs.go b/pkg/sentry/fsbridge/vfs.go new file mode 100644 index 000000000..e657c39bc --- /dev/null +++ b/pkg/sentry/fsbridge/vfs.go @@ -0,0 +1,134 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package fsbridge + +import ( + "io" + + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/fspath" + "gvisor.dev/gvisor/pkg/sentry/kernel/auth" + "gvisor.dev/gvisor/pkg/sentry/memmap" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/usermem" +) + +// fsFile implements File interface over vfs.FileDescription. +// +// +stateify savable +type vfsFile struct { + file *vfs.FileDescription +} + +var _ File = (*vfsFile)(nil) + +// NewVFSFile creates a new File over fs.File. +func NewVFSFile(file *vfs.FileDescription) File { + return &vfsFile{file: file} +} + +// PathnameWithDeleted implements File. +func (f *vfsFile) PathnameWithDeleted(ctx context.Context) string { + root := vfs.RootFromContext(ctx) + defer root.DecRef() + + vfsObj := f.file.VirtualDentry().Mount().Filesystem().VirtualFilesystem() + name, _ := vfsObj.PathnameWithDeleted(ctx, root, f.file.VirtualDentry()) + return name +} + +// ReadFull implements File. +func (f *vfsFile) ReadFull(ctx context.Context, dst usermem.IOSequence, offset int64) (int64, error) { + var total int64 + for dst.NumBytes() > 0 { + n, err := f.file.PRead(ctx, dst, offset+total, vfs.ReadOptions{}) + total += n + if err == io.EOF && total != 0 { + return total, io.ErrUnexpectedEOF + } else if err != nil { + return total, err + } + dst = dst.DropFirst64(n) + } + return total, nil +} + +// ConfigureMMap implements File. +func (f *vfsFile) ConfigureMMap(ctx context.Context, opts *memmap.MMapOpts) error { + return f.file.ConfigureMMap(ctx, opts) +} + +// Type implements File. +func (f *vfsFile) Type(ctx context.Context) (linux.FileMode, error) { + stat, err := f.file.Stat(ctx, vfs.StatOptions{}) + if err != nil { + return 0, err + } + return linux.FileMode(stat.Mode).FileType(), nil +} + +// IncRef implements File. +func (f *vfsFile) IncRef() { + f.file.IncRef() +} + +// DecRef implements File. +func (f *vfsFile) DecRef() { + f.file.DecRef() +} + +// fsLookup implements Lookup interface using fs.File. +// +// +stateify savable +type vfsLookup struct { + mntns *vfs.MountNamespace + + root vfs.VirtualDentry + workingDir vfs.VirtualDentry +} + +var _ Lookup = (*vfsLookup)(nil) + +// NewVFSLookup creates a new Lookup using VFS2. +func NewVFSLookup(mntns *vfs.MountNamespace, root, workingDir vfs.VirtualDentry) Lookup { + return &vfsLookup{ + mntns: mntns, + root: root, + workingDir: workingDir, + } +} + +// OpenPath implements Lookup. +// +// remainingTraversals is not configurable in VFS2, all callers are using the +// default anyways. +// +// TODO(gvisor.dev/issue/1623): Check mount has read and exec permission. +func (l *vfsLookup) OpenPath(ctx context.Context, path string, opts vfs.OpenOptions, _ *uint, resolveFinal bool) (File, error) { + vfsObj := l.mntns.Root().Mount().Filesystem().VirtualFilesystem() + creds := auth.CredentialsFromContext(ctx) + pop := &vfs.PathOperation{ + Root: l.root, + Start: l.root, + Path: fspath.Parse(path), + FollowFinalSymlink: resolveFinal, + } + fd, err := vfsObj.OpenAt(ctx, creds, pop, &opts) + if err != nil { + return nil, err + } + return &vfsFile{file: fd}, nil +} diff --git a/pkg/sentry/fsimpl/devtmpfs/devtmpfs.go b/pkg/sentry/fsimpl/devtmpfs/devtmpfs.go index e03a0c665..abd4f24e7 100644 --- a/pkg/sentry/fsimpl/devtmpfs/devtmpfs.go +++ b/pkg/sentry/fsimpl/devtmpfs/devtmpfs.go @@ -28,6 +28,9 @@ import ( "gvisor.dev/gvisor/pkg/sync" ) +// Name is the default filesystem name. +const Name = "devtmpfs" + // FilesystemType implements vfs.FilesystemType. type FilesystemType struct { initOnce sync.Once @@ -107,6 +110,7 @@ func (a *Accessor) wrapContext(ctx context.Context) *accessorContext { func (ac *accessorContext) Value(key interface{}) interface{} { switch key { case vfs.CtxMountNamespace: + ac.a.mntns.IncRef() return ac.a.mntns case vfs.CtxRoot: ac.a.root.IncRef() diff --git a/pkg/sentry/fsimpl/gofer/filesystem.go b/pkg/sentry/fsimpl/gofer/filesystem.go index 138adb9f7..5cfb0dc4c 100644 --- a/pkg/sentry/fsimpl/gofer/filesystem.go +++ b/pkg/sentry/fsimpl/gofer/filesystem.go @@ -400,6 +400,7 @@ func (fs *filesystem) unlinkAt(ctx context.Context, rp *vfs.ResolvingPath, dir b } vfsObj := rp.VirtualFilesystem() mntns := vfs.MountNamespaceFromContext(ctx) + defer mntns.DecRef() parent.dirMu.Lock() defer parent.dirMu.Unlock() childVFSD := parent.vfsd.Child(name) @@ -934,7 +935,9 @@ func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa if oldParent == newParent && oldName == newName { return nil } - if err := vfsObj.PrepareRenameDentry(vfs.MountNamespaceFromContext(ctx), &renamed.vfsd, replacedVFSD); err != nil { + mntns := vfs.MountNamespaceFromContext(ctx) + defer mntns.DecRef() + if err := vfsObj.PrepareRenameDentry(mntns, &renamed.vfsd, replacedVFSD); err != nil { return err } if err := renamed.file.rename(ctx, newParent.file, newName); err != nil { diff --git a/pkg/sentry/fsimpl/gofer/gofer.go b/pkg/sentry/fsimpl/gofer/gofer.go index d0552bd99..d00850e25 100644 --- a/pkg/sentry/fsimpl/gofer/gofer.go +++ b/pkg/sentry/fsimpl/gofer/gofer.go @@ -52,6 +52,9 @@ import ( "gvisor.dev/gvisor/pkg/usermem" ) +// Name is the default filesystem name. +const Name = "9p" + // FilesystemType implements vfs.FilesystemType. type FilesystemType struct{} diff --git a/pkg/sentry/fsimpl/kernfs/filesystem.go b/pkg/sentry/fsimpl/kernfs/filesystem.go index ee98eb66a..292f58afd 100644 --- a/pkg/sentry/fsimpl/kernfs/filesystem.go +++ b/pkg/sentry/fsimpl/kernfs/filesystem.go @@ -544,6 +544,7 @@ func (fs *Filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa } mntns := vfs.MountNamespaceFromContext(ctx) + defer mntns.DecRef() virtfs := rp.VirtualFilesystem() srcDirDentry := srcDirVFSD.Impl().(*Dentry) @@ -595,7 +596,10 @@ func (fs *Filesystem) RmdirAt(ctx context.Context, rp *vfs.ResolvingPath) error parentDentry := vfsd.Parent().Impl().(*Dentry) parentDentry.dirMu.Lock() defer parentDentry.dirMu.Unlock() - if err := virtfs.PrepareDeleteDentry(vfs.MountNamespaceFromContext(ctx), vfsd); err != nil { + + mntns := vfs.MountNamespaceFromContext(ctx) + defer mntns.DecRef() + if err := virtfs.PrepareDeleteDentry(mntns, vfsd); err != nil { return err } if err := parentDentry.inode.RmDir(ctx, rp.Component(), vfsd); err != nil { @@ -697,7 +701,9 @@ func (fs *Filesystem) UnlinkAt(ctx context.Context, rp *vfs.ResolvingPath) error parentDentry := vfsd.Parent().Impl().(*Dentry) parentDentry.dirMu.Lock() defer parentDentry.dirMu.Unlock() - if err := virtfs.PrepareDeleteDentry(vfs.MountNamespaceFromContext(ctx), vfsd); err != nil { + mntns := vfs.MountNamespaceFromContext(ctx) + defer mntns.DecRef() + if err := virtfs.PrepareDeleteDentry(mntns, vfsd); err != nil { return err } if err := parentDentry.inode.Unlink(ctx, rp.Component(), vfsd); err != nil { diff --git a/pkg/sentry/fsimpl/proc/BUILD b/pkg/sentry/fsimpl/proc/BUILD index 12aac2e6a..a83245866 100644 --- a/pkg/sentry/fsimpl/proc/BUILD +++ b/pkg/sentry/fsimpl/proc/BUILD @@ -14,6 +14,7 @@ go_library( "tasks_net.go", "tasks_sys.go", ], + visibility = ["//pkg/sentry:internal"], deps = [ "//pkg/abi/linux", "//pkg/context", diff --git a/pkg/sentry/fsimpl/proc/filesystem.go b/pkg/sentry/fsimpl/proc/filesystem.go index 11477b6a9..5c19d5522 100644 --- a/pkg/sentry/fsimpl/proc/filesystem.go +++ b/pkg/sentry/fsimpl/proc/filesystem.go @@ -26,15 +26,18 @@ import ( "gvisor.dev/gvisor/pkg/sentry/vfs" ) -// procFSType is the factory class for procfs. +// Name is the default filesystem name. +const Name = "proc" + +// FilesystemType is the factory class for procfs. // // +stateify savable -type procFSType struct{} +type FilesystemType struct{} -var _ vfs.FilesystemType = (*procFSType)(nil) +var _ vfs.FilesystemType = (*FilesystemType)(nil) // GetFilesystem implements vfs.FilesystemType. -func (ft *procFSType) GetFilesystem(ctx context.Context, vfsObj *vfs.VirtualFilesystem, creds *auth.Credentials, source string, opts vfs.GetFilesystemOptions) (*vfs.Filesystem, *vfs.Dentry, error) { +func (ft *FilesystemType) GetFilesystem(ctx context.Context, vfsObj *vfs.VirtualFilesystem, creds *auth.Credentials, source string, opts vfs.GetFilesystemOptions) (*vfs.Filesystem, *vfs.Dentry, error) { k := kernel.KernelFromContext(ctx) if k == nil { return nil, nil, fmt.Errorf("procfs requires a kernel") @@ -47,12 +50,13 @@ func (ft *procFSType) GetFilesystem(ctx context.Context, vfsObj *vfs.VirtualFile procfs := &kernfs.Filesystem{} procfs.VFSFilesystem().Init(vfsObj, procfs) - var data *InternalData + var cgroups map[string]string if opts.InternalData != nil { - data = opts.InternalData.(*InternalData) + data := opts.InternalData.(*InternalData) + cgroups = data.Cgroups } - _, dentry := newTasksInode(procfs, k, pidns, data.Cgroups) + _, dentry := newTasksInode(procfs, k, pidns, cgroups) return procfs.VFSFilesystem(), dentry.VFSDentry(), nil } diff --git a/pkg/sentry/fsimpl/proc/tasks_test.go b/pkg/sentry/fsimpl/proc/tasks_test.go index 6fc3524db..96c72cbc9 100644 --- a/pkg/sentry/fsimpl/proc/tasks_test.go +++ b/pkg/sentry/fsimpl/proc/tasks_test.go @@ -90,8 +90,7 @@ func setup(t *testing.T) *testutil.System { ctx := k.SupervisorContext() creds := auth.CredentialsFromContext(ctx) - vfsObj := vfs.New() - vfsObj.MustRegisterFilesystemType("procfs", &procFSType{}, &vfs.RegisterFilesystemTypeOptions{ + k.VFS.MustRegisterFilesystemType(Name, &FilesystemType{}, &vfs.RegisterFilesystemTypeOptions{ AllowUserMount: true, }) fsOpts := vfs.GetFilesystemOptions{ @@ -102,11 +101,11 @@ func setup(t *testing.T) *testutil.System { }, }, } - mntns, err := vfsObj.NewMountNamespace(ctx, creds, "", "procfs", &fsOpts) + mntns, err := k.VFS.NewMountNamespace(ctx, creds, "", Name, &fsOpts) if err != nil { t.Fatalf("NewMountNamespace(): %v", err) } - return testutil.NewSystem(ctx, t, vfsObj, mntns) + return testutil.NewSystem(ctx, t, k.VFS, mntns) } func TestTasksEmpty(t *testing.T) { @@ -131,7 +130,7 @@ func TestTasks(t *testing.T) { var tasks []*kernel.Task for i := 0; i < 5; i++ { tc := k.NewThreadGroup(nil, k.RootPIDNamespace(), kernel.NewSignalHandlers(), linux.SIGCHLD, k.GlobalInit().Limits()) - task, err := testutil.CreateTask(s.Ctx, fmt.Sprintf("name-%d", i), tc) + task, err := testutil.CreateTask(s.Ctx, fmt.Sprintf("name-%d", i), tc, s.MntNs, s.Root, s.Root) if err != nil { t.Fatalf("CreateTask(): %v", err) } @@ -213,7 +212,7 @@ func TestTasksOffset(t *testing.T) { k := kernel.KernelFromContext(s.Ctx) for i := 0; i < 3; i++ { tc := k.NewThreadGroup(nil, k.RootPIDNamespace(), kernel.NewSignalHandlers(), linux.SIGCHLD, k.GlobalInit().Limits()) - if _, err := testutil.CreateTask(s.Ctx, fmt.Sprintf("name-%d", i), tc); err != nil { + if _, err := testutil.CreateTask(s.Ctx, fmt.Sprintf("name-%d", i), tc, s.MntNs, s.Root, s.Root); err != nil { t.Fatalf("CreateTask(): %v", err) } } @@ -337,7 +336,7 @@ func TestTask(t *testing.T) { k := kernel.KernelFromContext(s.Ctx) tc := k.NewThreadGroup(nil, k.RootPIDNamespace(), kernel.NewSignalHandlers(), linux.SIGCHLD, k.GlobalInit().Limits()) - _, err := testutil.CreateTask(s.Ctx, "name", tc) + _, err := testutil.CreateTask(s.Ctx, "name", tc, s.MntNs, s.Root, s.Root) if err != nil { t.Fatalf("CreateTask(): %v", err) } @@ -352,7 +351,7 @@ func TestProcSelf(t *testing.T) { k := kernel.KernelFromContext(s.Ctx) tc := k.NewThreadGroup(nil, k.RootPIDNamespace(), kernel.NewSignalHandlers(), linux.SIGCHLD, k.GlobalInit().Limits()) - task, err := testutil.CreateTask(s.Ctx, "name", tc) + task, err := testutil.CreateTask(s.Ctx, "name", tc, s.MntNs, s.Root, s.Root) if err != nil { t.Fatalf("CreateTask(): %v", err) } @@ -433,7 +432,7 @@ func TestTree(t *testing.T) { var tasks []*kernel.Task for i := 0; i < 5; i++ { tc := k.NewThreadGroup(nil, k.RootPIDNamespace(), kernel.NewSignalHandlers(), linux.SIGCHLD, k.GlobalInit().Limits()) - task, err := testutil.CreateTask(s.Ctx, fmt.Sprintf("name-%d", i), tc) + task, err := testutil.CreateTask(s.Ctx, fmt.Sprintf("name-%d", i), tc, s.MntNs, s.Root, s.Root) if err != nil { t.Fatalf("CreateTask(): %v", err) } diff --git a/pkg/sentry/fsimpl/sys/BUILD b/pkg/sentry/fsimpl/sys/BUILD index 66c0d8bc8..a741e2bb6 100644 --- a/pkg/sentry/fsimpl/sys/BUILD +++ b/pkg/sentry/fsimpl/sys/BUILD @@ -7,6 +7,7 @@ go_library( srcs = [ "sys.go", ], + visibility = ["//pkg/sentry:internal"], deps = [ "//pkg/abi/linux", "//pkg/context", diff --git a/pkg/sentry/fsimpl/sys/sys.go b/pkg/sentry/fsimpl/sys/sys.go index d693fceae..c36c4fa11 100644 --- a/pkg/sentry/fsimpl/sys/sys.go +++ b/pkg/sentry/fsimpl/sys/sys.go @@ -28,6 +28,9 @@ import ( "gvisor.dev/gvisor/pkg/syserror" ) +// Name is the default filesystem name. +const Name = "sysfs" + // FilesystemType implements vfs.FilesystemType. type FilesystemType struct{} diff --git a/pkg/sentry/fsimpl/sys/sys_test.go b/pkg/sentry/fsimpl/sys/sys_test.go index 8b1cf0bd0..5d1ba5867 100644 --- a/pkg/sentry/fsimpl/sys/sys_test.go +++ b/pkg/sentry/fsimpl/sys/sys_test.go @@ -34,16 +34,15 @@ func newTestSystem(t *testing.T) *testutil.System { } ctx := k.SupervisorContext() creds := auth.CredentialsFromContext(ctx) - v := vfs.New() - v.MustRegisterFilesystemType("sysfs", sys.FilesystemType{}, &vfs.RegisterFilesystemTypeOptions{ + k.VFS.MustRegisterFilesystemType(sys.Name, sys.FilesystemType{}, &vfs.RegisterFilesystemTypeOptions{ AllowUserMount: true, }) - mns, err := v.NewMountNamespace(ctx, creds, "", "sysfs", &vfs.GetFilesystemOptions{}) + mns, err := k.VFS.NewMountNamespace(ctx, creds, "", sys.Name, &vfs.GetFilesystemOptions{}) if err != nil { t.Fatalf("Failed to create new mount namespace: %v", err) } - return testutil.NewSystem(ctx, t, v, mns) + return testutil.NewSystem(ctx, t, k.VFS, mns) } func TestReadCPUFile(t *testing.T) { diff --git a/pkg/sentry/fsimpl/testutil/BUILD b/pkg/sentry/fsimpl/testutil/BUILD index efd5974c4..e4f36f4ae 100644 --- a/pkg/sentry/fsimpl/testutil/BUILD +++ b/pkg/sentry/fsimpl/testutil/BUILD @@ -16,7 +16,7 @@ go_library( "//pkg/cpuid", "//pkg/fspath", "//pkg/memutil", - "//pkg/sentry/fs", + "//pkg/sentry/fsimpl/tmpfs", "//pkg/sentry/kernel", "//pkg/sentry/kernel/auth", "//pkg/sentry/kernel/sched", diff --git a/pkg/sentry/fsimpl/testutil/kernel.go b/pkg/sentry/fsimpl/testutil/kernel.go index 89f8c4915..a91b3ec4d 100644 --- a/pkg/sentry/fsimpl/testutil/kernel.go +++ b/pkg/sentry/fsimpl/testutil/kernel.go @@ -24,7 +24,7 @@ import ( "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/cpuid" "gvisor.dev/gvisor/pkg/memutil" - "gvisor.dev/gvisor/pkg/sentry/fs" + "gvisor.dev/gvisor/pkg/sentry/fsimpl/tmpfs" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/kernel/sched" @@ -33,6 +33,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/pgalloc" "gvisor.dev/gvisor/pkg/sentry/platform" "gvisor.dev/gvisor/pkg/sentry/time" + "gvisor.dev/gvisor/pkg/sentry/vfs" // Platforms are plugable. _ "gvisor.dev/gvisor/pkg/sentry/platform/kvm" @@ -99,26 +100,27 @@ func Boot() (*kernel.Kernel, error) { return nil, fmt.Errorf("initializing kernel: %v", err) } - ctx := k.SupervisorContext() + kernel.VFS2Enabled = true + + vfsObj := vfs.New() + vfsObj.MustRegisterFilesystemType(tmpfs.Name, &tmpfs.FilesystemType{}, &vfs.RegisterFilesystemTypeOptions{ + AllowUserMount: true, + AllowUserList: true, + }) + k.VFS = vfsObj - // Create mount namespace without root as it's the minimum required to create - // the global thread group. - mntns, err := fs.NewMountNamespace(ctx, nil) - if err != nil { - return nil, err - } ls, err := limits.NewLinuxLimitSet() if err != nil { return nil, err } - tg := k.NewThreadGroup(mntns, k.RootPIDNamespace(), kernel.NewSignalHandlers(), linux.SIGCHLD, ls) + tg := k.NewThreadGroup(nil, k.RootPIDNamespace(), kernel.NewSignalHandlers(), linux.SIGCHLD, ls) k.TestOnly_SetGlobalInit(tg) return k, nil } // CreateTask creates a new bare bones task for tests. -func CreateTask(ctx context.Context, name string, tc *kernel.ThreadGroup) (*kernel.Task, error) { +func CreateTask(ctx context.Context, name string, tc *kernel.ThreadGroup, mntns *vfs.MountNamespace, root, cwd vfs.VirtualDentry) (*kernel.Task, error) { k := kernel.KernelFromContext(ctx) config := &kernel.TaskConfig{ Kernel: k, @@ -129,6 +131,8 @@ func CreateTask(ctx context.Context, name string, tc *kernel.ThreadGroup) (*kern UTSNamespace: kernel.UTSNamespaceFromContext(ctx), IPCNamespace: kernel.IPCNamespaceFromContext(ctx), AbstractSocketNamespace: kernel.NewAbstractSocketNamespace(), + MountNamespaceVFS2: mntns, + FSContext: kernel.NewFSContextVFS2(root, cwd, 0022), } return k.TaskSet().NewTask(config) } diff --git a/pkg/sentry/fsimpl/testutil/testutil.go b/pkg/sentry/fsimpl/testutil/testutil.go index 69fd84ddd..b97e3534a 100644 --- a/pkg/sentry/fsimpl/testutil/testutil.go +++ b/pkg/sentry/fsimpl/testutil/testutil.go @@ -41,12 +41,12 @@ type System struct { Creds *auth.Credentials VFS *vfs.VirtualFilesystem Root vfs.VirtualDentry - mns *vfs.MountNamespace + MntNs *vfs.MountNamespace } // NewSystem constructs a System. // -// Precondition: Caller must hold a reference on mns, whose ownership +// Precondition: Caller must hold a reference on MntNs, whose ownership // is transferred to the new System. func NewSystem(ctx context.Context, t *testing.T, v *vfs.VirtualFilesystem, mns *vfs.MountNamespace) *System { s := &System{ @@ -54,7 +54,7 @@ func NewSystem(ctx context.Context, t *testing.T, v *vfs.VirtualFilesystem, mns Ctx: ctx, Creds: auth.CredentialsFromContext(ctx), VFS: v, - mns: mns, + MntNs: mns, Root: mns.Root(), } return s @@ -75,7 +75,7 @@ func (s *System) WithSubtest(t *testing.T) *System { Ctx: s.Ctx, Creds: s.Creds, VFS: s.VFS, - mns: s.mns, + MntNs: s.MntNs, Root: s.Root, } } @@ -90,7 +90,7 @@ func (s *System) WithTemporaryContext(ctx context.Context) *System { Ctx: ctx, Creds: s.Creds, VFS: s.VFS, - mns: s.mns, + MntNs: s.MntNs, Root: s.Root, } } @@ -98,7 +98,7 @@ func (s *System) WithTemporaryContext(ctx context.Context) *System { // Destroy release resources associated with a test system. func (s *System) Destroy() { s.Root.DecRef() - s.mns.DecRef() // Reference on mns passed to NewSystem. + s.MntNs.DecRef() // Reference on MntNs passed to NewSystem. } // ReadToEnd reads the contents of fd until EOF to a string. diff --git a/pkg/sentry/fsimpl/tmpfs/filesystem.go b/pkg/sentry/fsimpl/tmpfs/filesystem.go index 8785452b6..7f7b791c4 100644 --- a/pkg/sentry/fsimpl/tmpfs/filesystem.go +++ b/pkg/sentry/fsimpl/tmpfs/filesystem.go @@ -486,7 +486,9 @@ func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa vfsObj := rp.VirtualFilesystem() oldParentDir := oldParent.inode.impl.(*directory) newParentDir := newParent.inode.impl.(*directory) - if err := vfsObj.PrepareRenameDentry(vfs.MountNamespaceFromContext(ctx), renamedVFSD, replacedVFSD); err != nil { + mntns := vfs.MountNamespaceFromContext(ctx) + defer mntns.DecRef() + if err := vfsObj.PrepareRenameDentry(mntns, renamedVFSD, replacedVFSD); err != nil { return err } if replaced != nil { @@ -543,7 +545,9 @@ func (fs *filesystem) RmdirAt(ctx context.Context, rp *vfs.ResolvingPath) error } defer mnt.EndWrite() vfsObj := rp.VirtualFilesystem() - if err := vfsObj.PrepareDeleteDentry(vfs.MountNamespaceFromContext(ctx), childVFSD); err != nil { + mntns := vfs.MountNamespaceFromContext(ctx) + defer mntns.DecRef() + if err := vfsObj.PrepareDeleteDentry(mntns, childVFSD); err != nil { return err } parent.inode.impl.(*directory).childList.Remove(child) @@ -631,7 +635,9 @@ func (fs *filesystem) UnlinkAt(ctx context.Context, rp *vfs.ResolvingPath) error } defer mnt.EndWrite() vfsObj := rp.VirtualFilesystem() - if err := vfsObj.PrepareDeleteDentry(vfs.MountNamespaceFromContext(ctx), childVFSD); err != nil { + mntns := vfs.MountNamespaceFromContext(ctx) + defer mntns.DecRef() + if err := vfsObj.PrepareDeleteDentry(mntns, childVFSD); err != nil { return err } parent.inode.impl.(*directory).childList.Remove(child) diff --git a/pkg/sentry/fsimpl/tmpfs/tmpfs.go b/pkg/sentry/fsimpl/tmpfs/tmpfs.go index 2108d0f4d..c5bb17562 100644 --- a/pkg/sentry/fsimpl/tmpfs/tmpfs.go +++ b/pkg/sentry/fsimpl/tmpfs/tmpfs.go @@ -40,6 +40,9 @@ import ( "gvisor.dev/gvisor/pkg/syserror" ) +// Name is the default filesystem name. +const Name = "tmpfs" + // FilesystemType implements vfs.FilesystemType. type FilesystemType struct{} diff --git a/pkg/sentry/kernel/BUILD b/pkg/sentry/kernel/BUILD index 2231d6973..46306945f 100644 --- a/pkg/sentry/kernel/BUILD +++ b/pkg/sentry/kernel/BUILD @@ -157,6 +157,7 @@ go_library( "//pkg/context", "//pkg/cpuid", "//pkg/eventchannel", + "//pkg/fspath", "//pkg/log", "//pkg/metric", "//pkg/refs", @@ -167,6 +168,7 @@ go_library( "//pkg/sentry/fs", "//pkg/sentry/fs/lock", "//pkg/sentry/fs/timerfd", + "//pkg/sentry/fsbridge", "//pkg/sentry/hostcpu", "//pkg/sentry/inet", "//pkg/sentry/kernel/auth", diff --git a/pkg/sentry/kernel/fs_context.go b/pkg/sentry/kernel/fs_context.go index 2448c1d99..7218aa24e 100644 --- a/pkg/sentry/kernel/fs_context.go +++ b/pkg/sentry/kernel/fs_context.go @@ -19,6 +19,7 @@ import ( "gvisor.dev/gvisor/pkg/refs" "gvisor.dev/gvisor/pkg/sentry/fs" + "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/sync" ) @@ -37,10 +38,16 @@ type FSContext struct { // destroyed. root *fs.Dirent + // rootVFS2 is the filesystem root. + rootVFS2 vfs.VirtualDentry + // cwd is the current working directory. Will be nil iff the FSContext // has been destroyed. cwd *fs.Dirent + // cwdVFS2 is the current working directory. + cwdVFS2 vfs.VirtualDentry + // umask is the current file mode creation mask. When a thread using this // context invokes a syscall that creates a file, bits set in umask are // removed from the permissions that the file is created with. @@ -60,6 +67,19 @@ func newFSContext(root, cwd *fs.Dirent, umask uint) *FSContext { return &f } +// NewFSContextVFS2 returns a new filesystem context. +func NewFSContextVFS2(root, cwd vfs.VirtualDentry, umask uint) *FSContext { + root.IncRef() + cwd.IncRef() + f := FSContext{ + rootVFS2: root, + cwdVFS2: cwd, + umask: umask, + } + f.EnableLeakCheck("kernel.FSContext") + return &f +} + // destroy is the destructor for an FSContext. // // This will call DecRef on both root and cwd Dirents. If either call to @@ -75,11 +95,17 @@ func (f *FSContext) destroy() { f.mu.Lock() defer f.mu.Unlock() - f.root.DecRef() - f.root = nil - - f.cwd.DecRef() - f.cwd = nil + if VFS2Enabled { + f.rootVFS2.DecRef() + f.rootVFS2 = vfs.VirtualDentry{} + f.cwdVFS2.DecRef() + f.cwdVFS2 = vfs.VirtualDentry{} + } else { + f.root.DecRef() + f.root = nil + f.cwd.DecRef() + f.cwd = nil + } } // DecRef implements RefCounter.DecRef with destructor f.destroy. @@ -93,12 +119,21 @@ func (f *FSContext) DecRef() { func (f *FSContext) Fork() *FSContext { f.mu.Lock() defer f.mu.Unlock() - f.cwd.IncRef() - f.root.IncRef() + + if VFS2Enabled { + f.cwdVFS2.IncRef() + f.rootVFS2.IncRef() + } else { + f.cwd.IncRef() + f.root.IncRef() + } + return &FSContext{ - cwd: f.cwd, - root: f.root, - umask: f.umask, + cwd: f.cwd, + root: f.root, + cwdVFS2: f.cwdVFS2, + rootVFS2: f.rootVFS2, + umask: f.umask, } } @@ -109,12 +144,23 @@ func (f *FSContext) Fork() *FSContext { func (f *FSContext) WorkingDirectory() *fs.Dirent { f.mu.Lock() defer f.mu.Unlock() - if f.cwd != nil { - f.cwd.IncRef() - } + + f.cwd.IncRef() return f.cwd } +// WorkingDirectoryVFS2 returns the current working directory. +// +// This will return nil if called after destroy(), otherwise it will return a +// Dirent with a reference taken. +func (f *FSContext) WorkingDirectoryVFS2() vfs.VirtualDentry { + f.mu.Lock() + defer f.mu.Unlock() + + f.cwdVFS2.IncRef() + return f.cwdVFS2 +} + // SetWorkingDirectory sets the current working directory. // This will take an extra reference on the Dirent. // @@ -137,6 +183,20 @@ func (f *FSContext) SetWorkingDirectory(d *fs.Dirent) { old.DecRef() } +// SetWorkingDirectoryVFS2 sets the current working directory. +// This will take an extra reference on the VirtualDentry. +// +// This is not a valid call after destroy. +func (f *FSContext) SetWorkingDirectoryVFS2(d vfs.VirtualDentry) { + f.mu.Lock() + defer f.mu.Unlock() + + old := f.cwdVFS2 + f.cwdVFS2 = d + d.IncRef() + old.DecRef() +} + // RootDirectory returns the current filesystem root. // // This will return nil if called after destroy(), otherwise it will return a @@ -150,6 +210,18 @@ func (f *FSContext) RootDirectory() *fs.Dirent { return f.root } +// RootDirectoryVFS2 returns the current filesystem root. +// +// This will return nil if called after destroy(), otherwise it will return a +// Dirent with a reference taken. +func (f *FSContext) RootDirectoryVFS2() vfs.VirtualDentry { + f.mu.Lock() + defer f.mu.Unlock() + + f.rootVFS2.IncRef() + return f.rootVFS2 +} + // SetRootDirectory sets the root directory. // This will take an extra reference on the Dirent. // diff --git a/pkg/sentry/kernel/kernel.go b/pkg/sentry/kernel/kernel.go index 3ee760ba2..2665f057c 100644 --- a/pkg/sentry/kernel/kernel.go +++ b/pkg/sentry/kernel/kernel.go @@ -43,11 +43,13 @@ import ( "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/cpuid" "gvisor.dev/gvisor/pkg/eventchannel" + "gvisor.dev/gvisor/pkg/fspath" "gvisor.dev/gvisor/pkg/log" "gvisor.dev/gvisor/pkg/refs" "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/timerfd" + "gvisor.dev/gvisor/pkg/sentry/fsbridge" "gvisor.dev/gvisor/pkg/sentry/hostcpu" "gvisor.dev/gvisor/pkg/sentry/inet" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" @@ -71,6 +73,10 @@ import ( "gvisor.dev/gvisor/pkg/tcpip" ) +// VFS2Enabled is set to true when VFS2 is enabled. Added as a global for allow +// easy access everywhere. To be removed once VFS2 becomes the default. +var VFS2Enabled = false + // Kernel represents an emulated Linux kernel. It must be initialized by calling // Init() or LoadFrom(). // @@ -238,6 +244,9 @@ type Kernel struct { // SpecialOpts contains special kernel options. SpecialOpts + + // VFS keeps the filesystem state used across the kernel. + VFS *vfs.VirtualFilesystem } // InitKernelArgs holds arguments to Init. @@ -624,7 +633,7 @@ type CreateProcessArgs struct { // File is a passed host FD pointing to a file to load as the init binary. // // This is checked if and only if Filename is "". - File *fs.File + File fsbridge.File // Argvv is a list of arguments. Argv []string @@ -673,6 +682,13 @@ type CreateProcessArgs struct { // increment it). MountNamespace *fs.MountNamespace + // MountNamespaceVFS2 optionally contains the mount namespace for this + // process. If nil, the init process's mount namespace is used. + // + // Anyone setting MountNamespaceVFS2 must donate a reference (i.e. + // increment it). + MountNamespaceVFS2 *vfs.MountNamespace + // ContainerID is the container that the process belongs to. ContainerID string } @@ -711,11 +727,22 @@ func (ctx *createProcessContext) Value(key interface{}) interface{} { return ctx.args.Credentials case fs.CtxRoot: if ctx.args.MountNamespace != nil { - // MountNamespace.Root() will take a reference on the root - // dirent for us. + // MountNamespace.Root() will take a reference on the root dirent for us. return ctx.args.MountNamespace.Root() } return nil + case vfs.CtxRoot: + if ctx.args.MountNamespaceVFS2 == nil { + return nil + } + // MountNamespaceVFS2.Root() takes a reference on the root dirent for us. + return ctx.args.MountNamespaceVFS2.Root() + case vfs.CtxMountNamespace: + if ctx.k.globalInit == nil { + return nil + } + // MountNamespaceVFS2 takes a reference for us. + return ctx.k.GlobalInit().Leader().MountNamespaceVFS2() case fs.CtxDirentCacheLimiter: return ctx.k.DirentCacheLimiter case ktime.CtxRealtimeClock: @@ -757,34 +784,77 @@ func (k *Kernel) CreateProcess(args CreateProcessArgs) (*ThreadGroup, ThreadID, defer k.extMu.Unlock() log.Infof("EXEC: %v", args.Argv) - // Grab the mount namespace. - mounts := args.MountNamespace - if mounts == nil { - mounts = k.GlobalInit().Leader().MountNamespace() - mounts.IncRef() - } - - tg := k.NewThreadGroup(mounts, args.PIDNamespace, NewSignalHandlers(), linux.SIGCHLD, args.Limits) ctx := args.NewContext(k) - // Get the root directory from the MountNamespace. - root := mounts.Root() - // The call to newFSContext below will take a reference on root, so we - // don't need to hold this one. - defer root.DecRef() - - // Grab the working directory. - remainingTraversals := uint(args.MaxSymlinkTraversals) - wd := root // Default. - if args.WorkingDirectory != "" { - var err error - wd, err = mounts.FindInode(ctx, root, nil, args.WorkingDirectory, &remainingTraversals) - if err != nil { - return nil, 0, fmt.Errorf("failed to find initial working directory %q: %v", args.WorkingDirectory, err) + var ( + opener fsbridge.Lookup + fsContext *FSContext + mntns *fs.MountNamespace + ) + + if VFS2Enabled { + mntnsVFS2 := args.MountNamespaceVFS2 + if mntnsVFS2 == nil { + // MountNamespaceVFS2 adds a reference to the namespace, which is + // transferred to the new process. + mntnsVFS2 = k.GlobalInit().Leader().MountNamespaceVFS2() + } + // Get the root directory from the MountNamespace. + root := args.MountNamespaceVFS2.Root() + // The call to newFSContext below will take a reference on root, so we + // don't need to hold this one. + defer root.DecRef() + + // Grab the working directory. + wd := root // Default. + if args.WorkingDirectory != "" { + pop := vfs.PathOperation{ + Root: root, + Start: wd, + Path: fspath.Parse(args.WorkingDirectory), + FollowFinalSymlink: true, + } + var err error + wd, err = k.VFS.GetDentryAt(ctx, args.Credentials, &pop, &vfs.GetDentryOptions{ + CheckSearchable: true, + }) + if err != nil { + return nil, 0, fmt.Errorf("failed to find initial working directory %q: %v", args.WorkingDirectory, err) + } + defer wd.DecRef() + } + opener = fsbridge.NewVFSLookup(mntnsVFS2, root, wd) + fsContext = NewFSContextVFS2(root, wd, args.Umask) + + } else { + mntns = args.MountNamespace + if mntns == nil { + mntns = k.GlobalInit().Leader().MountNamespace() + mntns.IncRef() } - defer wd.DecRef() + // Get the root directory from the MountNamespace. + root := mntns.Root() + // The call to newFSContext below will take a reference on root, so we + // don't need to hold this one. + defer root.DecRef() + + // Grab the working directory. + remainingTraversals := args.MaxSymlinkTraversals + wd := root // Default. + if args.WorkingDirectory != "" { + var err error + wd, err = mntns.FindInode(ctx, root, nil, args.WorkingDirectory, &remainingTraversals) + if err != nil { + return nil, 0, fmt.Errorf("failed to find initial working directory %q: %v", args.WorkingDirectory, err) + } + defer wd.DecRef() + } + opener = fsbridge.NewFSLookup(mntns, root, wd) + fsContext = newFSContext(root, wd, args.Umask) } + tg := k.NewThreadGroup(mntns, args.PIDNamespace, NewSignalHandlers(), linux.SIGCHLD, args.Limits) + // Check which file to start from. switch { case args.Filename != "": @@ -805,11 +875,9 @@ func (k *Kernel) CreateProcess(args CreateProcessArgs) (*ThreadGroup, ThreadID, } // Create a fresh task context. - remainingTraversals = uint(args.MaxSymlinkTraversals) + remainingTraversals := args.MaxSymlinkTraversals loadArgs := loader.LoadArgs{ - Mounts: mounts, - Root: root, - WorkingDirectory: wd, + Opener: opener, RemainingTraversals: &remainingTraversals, ResolveFinal: true, Filename: args.Filename, @@ -834,13 +902,14 @@ func (k *Kernel) CreateProcess(args CreateProcessArgs) (*ThreadGroup, ThreadID, Kernel: k, ThreadGroup: tg, TaskContext: tc, - FSContext: newFSContext(root, wd, args.Umask), + FSContext: fsContext, FDTable: args.FDTable, Credentials: args.Credentials, AllowedCPUMask: sched.NewFullCPUSet(k.applicationCores), UTSNamespace: args.UTSNamespace, IPCNamespace: args.IPCNamespace, AbstractSocketNamespace: args.AbstractSocketNamespace, + MountNamespaceVFS2: args.MountNamespaceVFS2, ContainerID: args.ContainerID, } t, err := k.tasks.NewTask(config) @@ -1378,6 +1447,20 @@ func (ctx supervisorContext) Value(key interface{}) interface{} { return ctx.k.globalInit.mounts.Root() } return nil + case vfs.CtxRoot: + if ctx.k.globalInit == nil { + return vfs.VirtualDentry{} + } + mntns := ctx.k.GlobalInit().Leader().MountNamespaceVFS2() + defer mntns.DecRef() + // Root() takes a reference on the root dirent for us. + return mntns.Root() + case vfs.CtxMountNamespace: + if ctx.k.globalInit == nil { + return nil + } + // MountNamespaceVFS2() takes a reference for us. + return ctx.k.GlobalInit().Leader().MountNamespaceVFS2() case fs.CtxDirentCacheLimiter: return ctx.k.DirentCacheLimiter case ktime.CtxRealtimeClock: diff --git a/pkg/sentry/kernel/task.go b/pkg/sentry/kernel/task.go index 981e8c7fe..a3443ff21 100644 --- a/pkg/sentry/kernel/task.go +++ b/pkg/sentry/kernel/task.go @@ -424,6 +424,11 @@ type Task struct { // abstractSockets is protected by mu. abstractSockets *AbstractSocketNamespace + // mountNamespaceVFS2 is the task's mount namespace. + // + // It is protected by mu. It is owned by the task goroutine. + mountNamespaceVFS2 *vfs.MountNamespace + // parentDeathSignal is sent to this task's thread group when its parent exits. // // parentDeathSignal is protected by mu. @@ -638,6 +643,11 @@ func (t *Task) Value(key interface{}) interface{} { return int32(t.ThreadGroup().ID()) case fs.CtxRoot: return t.fsContext.RootDirectory() + case vfs.CtxRoot: + return t.fsContext.RootDirectoryVFS2() + case vfs.CtxMountNamespace: + t.mountNamespaceVFS2.IncRef() + return t.mountNamespaceVFS2 case fs.CtxDirentCacheLimiter: return t.k.DirentCacheLimiter case inet.CtxStack: @@ -701,6 +711,14 @@ func (t *Task) SyscallRestartBlock() SyscallRestartBlock { // Preconditions: The caller must be running on the task goroutine, or t.mu // must be locked. func (t *Task) IsChrooted() bool { + if VFS2Enabled { + realRoot := t.mountNamespaceVFS2.Root() + defer realRoot.DecRef() + root := t.fsContext.RootDirectoryVFS2() + defer root.DecRef() + return root != realRoot + } + realRoot := t.tg.mounts.Root() defer realRoot.DecRef() root := t.fsContext.RootDirectory() @@ -796,6 +814,15 @@ func (t *Task) MountNamespace() *fs.MountNamespace { return t.tg.mounts } +// MountNamespaceVFS2 returns t's MountNamespace. A reference is taken on the +// returned mount namespace. +func (t *Task) MountNamespaceVFS2() *vfs.MountNamespace { + t.mu.Lock() + defer t.mu.Unlock() + t.mountNamespaceVFS2.IncRef() + return t.mountNamespaceVFS2 +} + // AbstractSockets returns t's AbstractSocketNamespace. func (t *Task) AbstractSockets() *AbstractSocketNamespace { return t.abstractSockets diff --git a/pkg/sentry/kernel/task_clone.go b/pkg/sentry/kernel/task_clone.go index 53d4d211b..ba74b4c1c 100644 --- a/pkg/sentry/kernel/task_clone.go +++ b/pkg/sentry/kernel/task_clone.go @@ -199,6 +199,12 @@ func (t *Task) Clone(opts *CloneOptions) (ThreadID, *SyscallControl, error) { ipcns = NewIPCNamespace(userns) } + // TODO(b/63601033): Implement CLONE_NEWNS. + mntnsVFS2 := t.mountNamespaceVFS2 + if mntnsVFS2 != nil { + mntnsVFS2.IncRef() + } + tc, err := t.tc.Fork(t, t.k, !opts.NewAddressSpace) if err != nil { return 0, nil, err @@ -241,7 +247,9 @@ func (t *Task) Clone(opts *CloneOptions) (ThreadID, *SyscallControl, error) { rseqAddr := usermem.Addr(0) rseqSignature := uint32(0) if opts.NewThreadGroup { - tg.mounts.IncRef() + if tg.mounts != nil { + tg.mounts.IncRef() + } sh := t.tg.signalHandlers if opts.NewSignalHandlers { sh = sh.Fork() @@ -265,6 +273,7 @@ func (t *Task) Clone(opts *CloneOptions) (ThreadID, *SyscallControl, error) { UTSNamespace: utsns, IPCNamespace: ipcns, AbstractSocketNamespace: t.abstractSockets, + MountNamespaceVFS2: mntnsVFS2, RSeqAddr: rseqAddr, RSeqSignature: rseqSignature, ContainerID: t.ContainerID(), diff --git a/pkg/sentry/kernel/task_context.go b/pkg/sentry/kernel/task_context.go index 2d6e7733c..2be982684 100644 --- a/pkg/sentry/kernel/task_context.go +++ b/pkg/sentry/kernel/task_context.go @@ -136,7 +136,7 @@ func (t *Task) Stack() *arch.Stack { func (k *Kernel) LoadTaskImage(ctx context.Context, args loader.LoadArgs) (*TaskContext, *syserr.Error) { // If File is not nil, we should load that instead of resolving Filename. if args.File != nil { - args.Filename = args.File.MappedName(ctx) + args.Filename = args.File.PathnameWithDeleted(ctx) } // Prepare a new user address space to load into. diff --git a/pkg/sentry/kernel/task_exit.go b/pkg/sentry/kernel/task_exit.go index 435761e5a..c4ade6e8e 100644 --- a/pkg/sentry/kernel/task_exit.go +++ b/pkg/sentry/kernel/task_exit.go @@ -269,6 +269,13 @@ func (*runExitMain) execute(t *Task) taskRunState { t.fsContext.DecRef() t.fdTable.DecRef() + t.mu.Lock() + if t.mountNamespaceVFS2 != nil { + t.mountNamespaceVFS2.DecRef() + t.mountNamespaceVFS2 = nil + } + t.mu.Unlock() + // If this is the last task to exit from the thread group, release the // thread group's resources. if lastExiter { diff --git a/pkg/sentry/kernel/task_log.go b/pkg/sentry/kernel/task_log.go index 41259210c..6d737d3e5 100644 --- a/pkg/sentry/kernel/task_log.go +++ b/pkg/sentry/kernel/task_log.go @@ -198,18 +198,11 @@ func (t *Task) traceExecEvent(tc *TaskContext) { if !trace.IsEnabled() { return } - d := tc.MemoryManager.Executable() - if d == nil { + file := tc.MemoryManager.Executable() + if file == nil { trace.Logf(t.traceContext, traceCategory, "exec: << unknown >>") return } - defer d.DecRef() - root := t.fsContext.RootDirectory() - if root == nil { - trace.Logf(t.traceContext, traceCategory, "exec: << no root directory >>") - return - } - defer root.DecRef() - n, _ := d.FullName(root) - trace.Logf(t.traceContext, traceCategory, "exec: %s", n) + defer file.DecRef() + trace.Logf(t.traceContext, traceCategory, "exec: %s", file.PathnameWithDeleted(t)) } diff --git a/pkg/sentry/kernel/task_start.go b/pkg/sentry/kernel/task_start.go index de838beef..f9236a842 100644 --- a/pkg/sentry/kernel/task_start.go +++ b/pkg/sentry/kernel/task_start.go @@ -21,6 +21,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel/futex" "gvisor.dev/gvisor/pkg/sentry/kernel/sched" "gvisor.dev/gvisor/pkg/sentry/usage" + "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/usermem" ) @@ -80,6 +81,9 @@ type TaskConfig struct { // AbstractSocketNamespace is the AbstractSocketNamespace of the new task. AbstractSocketNamespace *AbstractSocketNamespace + // MountNamespaceVFS2 is the MountNamespace of the new task. + MountNamespaceVFS2 *vfs.MountNamespace + // RSeqAddr is a pointer to the the userspace linux.RSeq structure. RSeqAddr usermem.Addr @@ -116,28 +120,29 @@ func (ts *TaskSet) newTask(cfg *TaskConfig) (*Task, error) { parent: cfg.Parent, children: make(map[*Task]struct{}), }, - runState: (*runApp)(nil), - interruptChan: make(chan struct{}, 1), - signalMask: cfg.SignalMask, - signalStack: arch.SignalStack{Flags: arch.SignalStackFlagDisable}, - tc: *tc, - fsContext: cfg.FSContext, - fdTable: cfg.FDTable, - p: cfg.Kernel.Platform.NewContext(), - k: cfg.Kernel, - ptraceTracees: make(map[*Task]struct{}), - allowedCPUMask: cfg.AllowedCPUMask.Copy(), - ioUsage: &usage.IO{}, - niceness: cfg.Niceness, - netns: cfg.NetworkNamespaced, - utsns: cfg.UTSNamespace, - ipcns: cfg.IPCNamespace, - abstractSockets: cfg.AbstractSocketNamespace, - rseqCPU: -1, - rseqAddr: cfg.RSeqAddr, - rseqSignature: cfg.RSeqSignature, - futexWaiter: futex.NewWaiter(), - containerID: cfg.ContainerID, + runState: (*runApp)(nil), + interruptChan: make(chan struct{}, 1), + signalMask: cfg.SignalMask, + signalStack: arch.SignalStack{Flags: arch.SignalStackFlagDisable}, + tc: *tc, + fsContext: cfg.FSContext, + fdTable: cfg.FDTable, + p: cfg.Kernel.Platform.NewContext(), + k: cfg.Kernel, + ptraceTracees: make(map[*Task]struct{}), + allowedCPUMask: cfg.AllowedCPUMask.Copy(), + ioUsage: &usage.IO{}, + niceness: cfg.Niceness, + netns: cfg.NetworkNamespaced, + utsns: cfg.UTSNamespace, + ipcns: cfg.IPCNamespace, + abstractSockets: cfg.AbstractSocketNamespace, + mountNamespaceVFS2: cfg.MountNamespaceVFS2, + rseqCPU: -1, + rseqAddr: cfg.RSeqAddr, + rseqSignature: cfg.RSeqSignature, + futexWaiter: futex.NewWaiter(), + containerID: cfg.ContainerID, } t.creds.Store(cfg.Credentials) t.endStopCond.L = &t.tg.signalHandlers.mu diff --git a/pkg/sentry/kernel/thread_group.go b/pkg/sentry/kernel/thread_group.go index 768e958d2..268f62e9d 100644 --- a/pkg/sentry/kernel/thread_group.go +++ b/pkg/sentry/kernel/thread_group.go @@ -256,7 +256,7 @@ type ThreadGroup struct { tty *TTY } -// NewThreadGroup returns a new, empty thread group in PID namespace ns. The +// NewThreadGroup returns a new, empty thread group in PID namespace pidns. The // thread group leader will send its parent terminationSignal when it exits. // The new thread group isn't visible to the system until a task has been // created inside of it by a successful call to TaskSet.NewTask. @@ -317,7 +317,9 @@ func (tg *ThreadGroup) release() { for _, it := range its { it.DestroyTimer() } - tg.mounts.DecRef() + if tg.mounts != nil { + tg.mounts.DecRef() + } } // forEachChildThreadGroupLocked indicates over all child ThreadGroups. diff --git a/pkg/sentry/loader/BUILD b/pkg/sentry/loader/BUILD index 23790378a..c6aa65f28 100644 --- a/pkg/sentry/loader/BUILD +++ b/pkg/sentry/loader/BUILD @@ -33,6 +33,7 @@ go_library( "//pkg/sentry/fs", "//pkg/sentry/fs/anon", "//pkg/sentry/fs/fsutil", + "//pkg/sentry/fsbridge", "//pkg/sentry/kernel/auth", "//pkg/sentry/limits", "//pkg/sentry/memmap", @@ -40,6 +41,7 @@ go_library( "//pkg/sentry/pgalloc", "//pkg/sentry/uniqueid", "//pkg/sentry/usage", + "//pkg/sentry/vfs", "//pkg/syserr", "//pkg/syserror", "//pkg/usermem", diff --git a/pkg/sentry/loader/elf.go b/pkg/sentry/loader/elf.go index 122ed05c2..616fafa2c 100644 --- a/pkg/sentry/loader/elf.go +++ b/pkg/sentry/loader/elf.go @@ -27,7 +27,7 @@ import ( "gvisor.dev/gvisor/pkg/cpuid" "gvisor.dev/gvisor/pkg/log" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/fs" + "gvisor.dev/gvisor/pkg/sentry/fsbridge" "gvisor.dev/gvisor/pkg/sentry/limits" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/mm" @@ -97,11 +97,11 @@ type elfInfo struct { // accepts from the ELF, and it doesn't parse unnecessary parts of the file. // // ctx may be nil if f does not need it. -func parseHeader(ctx context.Context, f *fs.File) (elfInfo, error) { +func parseHeader(ctx context.Context, f fsbridge.File) (elfInfo, error) { // Check ident first; it will tell us the endianness of the rest of the // structs. var ident [elf.EI_NIDENT]byte - _, err := readFull(ctx, f, usermem.BytesIOSequence(ident[:]), 0) + _, err := f.ReadFull(ctx, usermem.BytesIOSequence(ident[:]), 0) if err != nil { log.Infof("Error reading ELF ident: %v", err) // The entire ident array always exists. @@ -137,7 +137,7 @@ func parseHeader(ctx context.Context, f *fs.File) (elfInfo, error) { var hdr elf.Header64 hdrBuf := make([]byte, header64Size) - _, err = readFull(ctx, f, usermem.BytesIOSequence(hdrBuf), 0) + _, err = f.ReadFull(ctx, usermem.BytesIOSequence(hdrBuf), 0) if err != nil { log.Infof("Error reading ELF header: %v", err) // The entire header always exists. @@ -187,7 +187,7 @@ func parseHeader(ctx context.Context, f *fs.File) (elfInfo, error) { } phdrBuf := make([]byte, totalPhdrSize) - _, err = readFull(ctx, f, usermem.BytesIOSequence(phdrBuf), int64(hdr.Phoff)) + _, err = f.ReadFull(ctx, usermem.BytesIOSequence(phdrBuf), int64(hdr.Phoff)) if err != nil { log.Infof("Error reading ELF phdrs: %v", err) // If phdrs were specified, they should all exist. @@ -227,7 +227,7 @@ func parseHeader(ctx context.Context, f *fs.File) (elfInfo, error) { // mapSegment maps a phdr into the Task. offset is the offset to apply to // phdr.Vaddr. -func mapSegment(ctx context.Context, m *mm.MemoryManager, f *fs.File, phdr *elf.ProgHeader, offset usermem.Addr) error { +func mapSegment(ctx context.Context, m *mm.MemoryManager, f fsbridge.File, phdr *elf.ProgHeader, offset usermem.Addr) error { // We must make a page-aligned mapping. adjust := usermem.Addr(phdr.Vaddr).PageOffset() @@ -395,7 +395,7 @@ type loadedELF struct { // // Preconditions: // * f is an ELF file -func loadParsedELF(ctx context.Context, m *mm.MemoryManager, f *fs.File, info elfInfo, sharedLoadOffset usermem.Addr) (loadedELF, error) { +func loadParsedELF(ctx context.Context, m *mm.MemoryManager, f fsbridge.File, info elfInfo, sharedLoadOffset usermem.Addr) (loadedELF, error) { first := true var start, end usermem.Addr var interpreter string @@ -431,7 +431,7 @@ func loadParsedELF(ctx context.Context, m *mm.MemoryManager, f *fs.File, info el } path := make([]byte, phdr.Filesz) - _, err := readFull(ctx, f, usermem.BytesIOSequence(path), int64(phdr.Off)) + _, err := f.ReadFull(ctx, usermem.BytesIOSequence(path), int64(phdr.Off)) if err != nil { // If an interpreter was specified, it should exist. ctx.Infof("Error reading PT_INTERP path: %v", err) @@ -564,7 +564,7 @@ func loadParsedELF(ctx context.Context, m *mm.MemoryManager, f *fs.File, info el // Preconditions: // * f is an ELF file // * f is the first ELF loaded into m -func loadInitialELF(ctx context.Context, m *mm.MemoryManager, fs *cpuid.FeatureSet, f *fs.File) (loadedELF, arch.Context, error) { +func loadInitialELF(ctx context.Context, m *mm.MemoryManager, fs *cpuid.FeatureSet, f fsbridge.File) (loadedELF, arch.Context, error) { info, err := parseHeader(ctx, f) if err != nil { ctx.Infof("Failed to parse initial ELF: %v", err) @@ -602,7 +602,7 @@ func loadInitialELF(ctx context.Context, m *mm.MemoryManager, fs *cpuid.FeatureS // // Preconditions: // * f is an ELF file -func loadInterpreterELF(ctx context.Context, m *mm.MemoryManager, f *fs.File, initial loadedELF) (loadedELF, error) { +func loadInterpreterELF(ctx context.Context, m *mm.MemoryManager, f fsbridge.File, initial loadedELF) (loadedELF, error) { info, err := parseHeader(ctx, f) if err != nil { if err == syserror.ENOEXEC { @@ -649,16 +649,14 @@ func loadELF(ctx context.Context, args LoadArgs) (loadedELF, arch.Context, error // Refresh the traversal limit. *args.RemainingTraversals = linux.MaxSymlinkTraversals args.Filename = bin.interpreter - d, i, err := openPath(ctx, args) + intFile, err := openPath(ctx, args) if err != nil { ctx.Infof("Error opening interpreter %s: %v", bin.interpreter, err) return loadedELF{}, nil, err } - defer i.DecRef() - // We don't need the Dirent. - d.DecRef() + defer intFile.DecRef() - interp, err = loadInterpreterELF(ctx, args.MemoryManager, i, bin) + interp, err = loadInterpreterELF(ctx, args.MemoryManager, intFile, bin) if err != nil { ctx.Infof("Error loading interpreter: %v", err) return loadedELF{}, nil, err diff --git a/pkg/sentry/loader/interpreter.go b/pkg/sentry/loader/interpreter.go index 098a45d36..3886b4d33 100644 --- a/pkg/sentry/loader/interpreter.go +++ b/pkg/sentry/loader/interpreter.go @@ -19,7 +19,7 @@ import ( "io" "gvisor.dev/gvisor/pkg/context" - "gvisor.dev/gvisor/pkg/sentry/fs" + "gvisor.dev/gvisor/pkg/sentry/fsbridge" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/usermem" ) @@ -37,9 +37,9 @@ const ( ) // parseInterpreterScript returns the interpreter path and argv. -func parseInterpreterScript(ctx context.Context, filename string, f *fs.File, argv []string) (newpath string, newargv []string, err error) { +func parseInterpreterScript(ctx context.Context, filename string, f fsbridge.File, argv []string) (newpath string, newargv []string, err error) { line := make([]byte, interpMaxLineLength) - n, err := readFull(ctx, f, usermem.BytesIOSequence(line), 0) + n, err := f.ReadFull(ctx, usermem.BytesIOSequence(line), 0) // Short read is OK. if err != nil && err != io.ErrUnexpectedEOF { if err == io.EOF { diff --git a/pkg/sentry/loader/loader.go b/pkg/sentry/loader/loader.go index 9a613d6b7..d6675b8f0 100644 --- a/pkg/sentry/loader/loader.go +++ b/pkg/sentry/loader/loader.go @@ -20,7 +20,6 @@ import ( "fmt" "io" "path" - "strings" "gvisor.dev/gvisor/pkg/abi" "gvisor.dev/gvisor/pkg/abi/linux" @@ -29,8 +28,10 @@ import ( "gvisor.dev/gvisor/pkg/rand" "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/fs" + "gvisor.dev/gvisor/pkg/sentry/fsbridge" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/mm" + "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/syserr" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/usermem" @@ -41,16 +42,6 @@ type LoadArgs struct { // MemoryManager is the memory manager to load the executable into. MemoryManager *mm.MemoryManager - // Mounts is the mount namespace in which to look up Filename. - Mounts *fs.MountNamespace - - // Root is the root directory under which to look up Filename. - Root *fs.Dirent - - // WorkingDirectory is the working directory under which to look up - // Filename. - WorkingDirectory *fs.Dirent - // RemainingTraversals is the maximum number of symlinks to follow to // resolve Filename. This counter is passed by reference to keep it // updated throughout the call stack. @@ -65,7 +56,12 @@ type LoadArgs struct { // File is an open fs.File object of the executable. If File is not // nil, then File will be loaded and Filename will be ignored. - File *fs.File + // + // The caller is responsible for checking that the user can execute this file. + File fsbridge.File + + // Opener is used to open the executable file when 'File' is nil. + Opener fsbridge.Lookup // CloseOnExec indicates that the executable (or one of its parent // directories) was opened with O_CLOEXEC. If the executable is an @@ -106,103 +102,32 @@ func readFull(ctx context.Context, f *fs.File, dst usermem.IOSequence, offset in // installed in the Task FDTable. The caller takes ownership of both. // // args.Filename must be a readable, executable, regular file. -func openPath(ctx context.Context, args LoadArgs) (*fs.Dirent, *fs.File, error) { +func openPath(ctx context.Context, args LoadArgs) (fsbridge.File, error) { if args.Filename == "" { ctx.Infof("cannot open empty name") - return nil, nil, syserror.ENOENT - } - - var d *fs.Dirent - var err error - if args.ResolveFinal { - d, err = args.Mounts.FindInode(ctx, args.Root, args.WorkingDirectory, args.Filename, args.RemainingTraversals) - } else { - d, err = args.Mounts.FindLink(ctx, args.Root, args.WorkingDirectory, args.Filename, args.RemainingTraversals) - } - if err != nil { - return nil, nil, err - } - // Defer a DecRef for the sake of failure cases. - defer d.DecRef() - - if !args.ResolveFinal && fs.IsSymlink(d.Inode.StableAttr) { - return nil, nil, syserror.ELOOP - } - - if err := checkPermission(ctx, d); err != nil { - return nil, nil, err - } - - // If they claim it's a directory, then make sure. - // - // N.B. we reject directories below, but we must first reject - // non-directories passed as directories. - if strings.HasSuffix(args.Filename, "/") && !fs.IsDir(d.Inode.StableAttr) { - return nil, nil, syserror.ENOTDIR - } - - if err := checkIsRegularFile(ctx, d, args.Filename); err != nil { - return nil, nil, err - } - - f, err := d.Inode.GetFile(ctx, d, fs.FileFlags{Read: true}) - if err != nil { - return nil, nil, err - } - // Defer a DecRef for the sake of failure cases. - defer f.DecRef() - - if err := checkPread(ctx, f, args.Filename); err != nil { - return nil, nil, err - } - - d.IncRef() - f.IncRef() - return d, f, err -} - -// checkFile performs checks on a file to be executed. -func checkFile(ctx context.Context, f *fs.File, filename string) error { - if err := checkPermission(ctx, f.Dirent); err != nil { - return err - } - - if err := checkIsRegularFile(ctx, f.Dirent, filename); err != nil { - return err + return nil, syserror.ENOENT } - return checkPread(ctx, f, filename) -} - -// checkPermission checks whether the file is readable and executable. -func checkPermission(ctx context.Context, d *fs.Dirent) error { - perms := fs.PermMask{ - // TODO(gvisor.dev/issue/160): Linux requires only execute - // permission, not read. However, our backing filesystems may - // prevent us from reading the file without read permission. - // - // Additionally, a task with a non-readable executable has - // additional constraints on access via ptrace and procfs. - Read: true, - Execute: true, + // TODO(gvisor.dev/issue/160): Linux requires only execute permission, + // not read. However, our backing filesystems may prevent us from reading + // the file without read permission. Additionally, a task with a + // non-readable executable has additional constraints on access via + // ptrace and procfs. + opts := vfs.OpenOptions{ + Flags: linux.O_RDONLY, + FileExec: true, } - return d.Inode.CheckPermission(ctx, perms) + return args.Opener.OpenPath(ctx, args.Filename, opts, args.RemainingTraversals, args.ResolveFinal) } // checkIsRegularFile prevents us from trying to execute a directory, pipe, etc. -func checkIsRegularFile(ctx context.Context, d *fs.Dirent, filename string) error { - attr := d.Inode.StableAttr - if !fs.IsRegular(attr) { - ctx.Infof("%s is not regular: %v", filename, attr) - return syserror.EACCES +func checkIsRegularFile(ctx context.Context, file fsbridge.File, filename string) error { + t, err := file.Type(ctx) + if err != nil { + return err } - return nil -} - -// checkPread checks whether we can read the file at arbitrary offsets. -func checkPread(ctx context.Context, f *fs.File, filename string) error { - if !f.Flags().Pread { - ctx.Infof("%s cannot be read at an offset: %+v", filename, f.Flags()) + if t != linux.ModeRegular { + ctx.Infof("%q is not a regular file: %v", filename, t) return syserror.EACCES } return nil @@ -224,8 +149,10 @@ const ( maxLoaderAttempts = 6 ) -// loadExecutable loads an executable that is pointed to by args.File. If nil, -// the path args.Filename is resolved and loaded. If the executable is an +// loadExecutable loads an executable that is pointed to by args.File. The +// caller is responsible for checking that the user can execute this file. +// If nil, the path args.Filename is resolved and loaded (check that the user +// can execute this file is done here in this case). If the executable is an // interpreter script rather than an ELF, the binary of the corresponding // interpreter will be loaded. // @@ -234,37 +161,27 @@ const ( // * arch.Context matching the binary arch // * fs.Dirent of the binary file // * Possibly updated args.Argv -func loadExecutable(ctx context.Context, args LoadArgs) (loadedELF, arch.Context, *fs.Dirent, []string, error) { +func loadExecutable(ctx context.Context, args LoadArgs) (loadedELF, arch.Context, fsbridge.File, []string, error) { for i := 0; i < maxLoaderAttempts; i++ { - var ( - d *fs.Dirent - err error - ) if args.File == nil { - d, args.File, err = openPath(ctx, args) - // We will return d in the successful case, but defer a DecRef for the - // sake of intermediate loops and failure cases. - if d != nil { - defer d.DecRef() - } - if args.File != nil { - defer args.File.DecRef() + var err error + args.File, err = openPath(ctx, args) + if err != nil { + ctx.Infof("Error opening %s: %v", args.Filename, err) + return loadedELF{}, nil, nil, nil, err } + // Ensure file is release in case the code loops or errors out. + defer args.File.DecRef() } else { - d = args.File.Dirent - d.IncRef() - defer d.DecRef() - err = checkFile(ctx, args.File, args.Filename) - } - if err != nil { - ctx.Infof("Error opening %s: %v", args.Filename, err) - return loadedELF{}, nil, nil, nil, err + if err := checkIsRegularFile(ctx, args.File, args.Filename); err != nil { + return loadedELF{}, nil, nil, nil, err + } } // Check the header. Is this an ELF or interpreter script? var hdr [4]uint8 // N.B. We assume that reading from a regular file cannot block. - _, err = readFull(ctx, args.File, usermem.BytesIOSequence(hdr[:]), 0) + _, err := args.File.ReadFull(ctx, usermem.BytesIOSequence(hdr[:]), 0) // Allow unexpected EOF, as a valid executable could be only three bytes // (e.g., #!a). if err != nil && err != io.ErrUnexpectedEOF { @@ -281,9 +198,10 @@ func loadExecutable(ctx context.Context, args LoadArgs) (loadedELF, arch.Context ctx.Infof("Error loading ELF: %v", err) return loadedELF{}, nil, nil, nil, err } - // An ELF is always terminal. Hold on to d. - d.IncRef() - return loaded, ac, d, args.Argv, err + // An ELF is always terminal. Hold on to file. + args.File.IncRef() + return loaded, ac, args.File, args.Argv, err + case bytes.Equal(hdr[:2], []byte(interpreterScriptMagic)): if args.CloseOnExec { return loadedELF{}, nil, nil, nil, syserror.ENOENT @@ -295,6 +213,7 @@ func loadExecutable(ctx context.Context, args LoadArgs) (loadedELF, arch.Context } // Refresh the traversal limit for the interpreter. *args.RemainingTraversals = linux.MaxSymlinkTraversals + default: ctx.Infof("Unknown magic: %v", hdr) return loadedELF{}, nil, nil, nil, syserror.ENOEXEC @@ -317,11 +236,11 @@ func loadExecutable(ctx context.Context, args LoadArgs) (loadedELF, arch.Context // * Load is called on the Task goroutine. func Load(ctx context.Context, args LoadArgs, extraAuxv []arch.AuxEntry, vdso *VDSO) (abi.OS, arch.Context, string, *syserr.Error) { // Load the executable itself. - loaded, ac, d, newArgv, err := loadExecutable(ctx, args) + loaded, ac, file, newArgv, err := loadExecutable(ctx, args) if err != nil { return 0, nil, "", syserr.NewDynamic(fmt.Sprintf("Failed to load %s: %v", args.Filename, err), syserr.FromError(err).ToLinux()) } - defer d.DecRef() + defer file.DecRef() // Load the VDSO. vdsoAddr, err := loadVDSO(ctx, args.MemoryManager, vdso, loaded) @@ -390,7 +309,7 @@ func Load(ctx context.Context, args LoadArgs, extraAuxv []arch.AuxEntry, vdso *V m.SetEnvvStart(sl.EnvvStart) m.SetEnvvEnd(sl.EnvvEnd) m.SetAuxv(auxv) - m.SetExecutable(d) + m.SetExecutable(file) ac.SetIP(uintptr(loaded.entry)) ac.SetStack(uintptr(stack.Bottom)) diff --git a/pkg/sentry/loader/vdso.go b/pkg/sentry/loader/vdso.go index 52f446ed7..161b28c2c 100644 --- a/pkg/sentry/loader/vdso.go +++ b/pkg/sentry/loader/vdso.go @@ -27,6 +27,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/anon" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" + "gvisor.dev/gvisor/pkg/sentry/fsbridge" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/mm" "gvisor.dev/gvisor/pkg/sentry/pgalloc" @@ -69,6 +70,8 @@ type byteReader struct { var _ fs.FileOperations = (*byteReader)(nil) // newByteReaderFile creates a fake file to read data from. +// +// TODO(gvisor.dev/issue/1623): Convert to VFS2. func newByteReaderFile(ctx context.Context, data []byte) *fs.File { // Create a fake inode. inode := fs.NewInode( @@ -123,7 +126,7 @@ func (b *byteReader) Write(ctx context.Context, file *fs.File, src usermem.IOSeq // * PT_LOAD segments don't extend beyond the end of the file. // // ctx may be nil if f does not need it. -func validateVDSO(ctx context.Context, f *fs.File, size uint64) (elfInfo, error) { +func validateVDSO(ctx context.Context, f fsbridge.File, size uint64) (elfInfo, error) { info, err := parseHeader(ctx, f) if err != nil { log.Infof("Unable to parse VDSO header: %v", err) @@ -221,7 +224,7 @@ type VDSO struct { // PrepareVDSO validates the system VDSO and returns a VDSO, containing the // param page for updating by the kernel. func PrepareVDSO(ctx context.Context, mfp pgalloc.MemoryFileProvider) (*VDSO, error) { - vdsoFile := newByteReaderFile(ctx, vdsoBin) + vdsoFile := fsbridge.NewFSFile(newByteReaderFile(ctx, vdsoBin)) // First make sure the VDSO is valid. vdsoFile does not use ctx, so a // nil context can be passed. diff --git a/pkg/sentry/mm/BUILD b/pkg/sentry/mm/BUILD index e5729ced5..73591dab7 100644 --- a/pkg/sentry/mm/BUILD +++ b/pkg/sentry/mm/BUILD @@ -105,8 +105,8 @@ go_library( "//pkg/safecopy", "//pkg/safemem", "//pkg/sentry/arch", - "//pkg/sentry/fs", "//pkg/sentry/fs/proc/seqfile", + "//pkg/sentry/fsbridge", "//pkg/sentry/kernel/auth", "//pkg/sentry/kernel/futex", "//pkg/sentry/kernel/shm", diff --git a/pkg/sentry/mm/metadata.go b/pkg/sentry/mm/metadata.go index f550acae0..6a49334f4 100644 --- a/pkg/sentry/mm/metadata.go +++ b/pkg/sentry/mm/metadata.go @@ -16,7 +16,7 @@ package mm import ( "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/fs" + "gvisor.dev/gvisor/pkg/sentry/fsbridge" "gvisor.dev/gvisor/pkg/usermem" ) @@ -132,7 +132,7 @@ func (mm *MemoryManager) SetAuxv(auxv arch.Auxv) { // // An additional reference will be taken in the case of a non-nil executable, // which must be released by the caller. -func (mm *MemoryManager) Executable() *fs.Dirent { +func (mm *MemoryManager) Executable() fsbridge.File { mm.metadataMu.Lock() defer mm.metadataMu.Unlock() @@ -147,15 +147,15 @@ func (mm *MemoryManager) Executable() *fs.Dirent { // SetExecutable sets the executable. // // This takes a reference on d. -func (mm *MemoryManager) SetExecutable(d *fs.Dirent) { +func (mm *MemoryManager) SetExecutable(file fsbridge.File) { mm.metadataMu.Lock() // Grab a new reference. - d.IncRef() + file.IncRef() // Set the executable. orig := mm.executable - mm.executable = d + mm.executable = file mm.metadataMu.Unlock() diff --git a/pkg/sentry/mm/mm.go b/pkg/sentry/mm/mm.go index 09e582dd3..637383c7a 100644 --- a/pkg/sentry/mm/mm.go +++ b/pkg/sentry/mm/mm.go @@ -37,7 +37,7 @@ package mm import ( "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/fs" + "gvisor.dev/gvisor/pkg/sentry/fsbridge" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/pgalloc" "gvisor.dev/gvisor/pkg/sentry/platform" @@ -215,7 +215,7 @@ type MemoryManager struct { // is not nil, it holds a reference on the Dirent. // // executable is protected by metadataMu. - executable *fs.Dirent + executable fsbridge.File // dumpability describes if and how this MemoryManager may be dumped to // userspace. diff --git a/pkg/sentry/strace/strace.go b/pkg/sentry/strace/strace.go index a796b2396..46cb2a1cc 100644 --- a/pkg/sentry/strace/strace.go +++ b/pkg/sentry/strace/strace.go @@ -141,6 +141,10 @@ func path(t *kernel.Task, addr usermem.Addr) string { } func fd(t *kernel.Task, fd int32) string { + if kernel.VFS2Enabled { + return fdVFS2(t, fd) + } + root := t.FSContext().RootDirectory() if root != nil { defer root.DecRef() @@ -169,6 +173,30 @@ func fd(t *kernel.Task, fd int32) string { return fmt.Sprintf("%#x %s", fd, name) } +func fdVFS2(t *kernel.Task, fd int32) string { + root := t.FSContext().RootDirectoryVFS2() + defer root.DecRef() + + vfsObj := root.Mount().Filesystem().VirtualFilesystem() + if fd == linux.AT_FDCWD { + wd := t.FSContext().WorkingDirectoryVFS2() + defer wd.DecRef() + + name, _ := vfsObj.PathnameWithDeleted(t, root, wd) + return fmt.Sprintf("AT_FDCWD %s", name) + } + + file := t.GetFileVFS2(fd) + if file == nil { + // Cast FD to uint64 to avoid printing negative hex. + return fmt.Sprintf("%#x (bad FD)", uint64(fd)) + } + defer file.DecRef() + + name, _ := vfsObj.PathnameWithDeleted(t, root, file.VirtualDentry()) + return fmt.Sprintf("%#x %s", fd, name) +} + func fdpair(t *kernel.Task, addr usermem.Addr) string { var fds [2]int32 _, err := t.CopyIn(addr, &fds) diff --git a/pkg/sentry/syscalls/linux/BUILD b/pkg/sentry/syscalls/linux/BUILD index be16ee686..0d24fd3c4 100644 --- a/pkg/sentry/syscalls/linux/BUILD +++ b/pkg/sentry/syscalls/linux/BUILD @@ -74,6 +74,7 @@ go_library( "//pkg/sentry/fs/lock", "//pkg/sentry/fs/timerfd", "//pkg/sentry/fs/tmpfs", + "//pkg/sentry/fsbridge", "//pkg/sentry/kernel", "//pkg/sentry/kernel/auth", "//pkg/sentry/kernel/epoll", diff --git a/pkg/sentry/syscalls/linux/sys_prctl.go b/pkg/sentry/syscalls/linux/sys_prctl.go index 98db32d77..9c6728530 100644 --- a/pkg/sentry/syscalls/linux/sys_prctl.go +++ b/pkg/sentry/syscalls/linux/sys_prctl.go @@ -20,6 +20,7 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/fs" + "gvisor.dev/gvisor/pkg/sentry/fsbridge" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/mm" @@ -135,7 +136,7 @@ func Prctl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall } // Set the underlying executable. - t.MemoryManager().SetExecutable(file.Dirent) + t.MemoryManager().SetExecutable(fsbridge.NewFSFile(file)) case linux.PR_SET_MM_AUXV, linux.PR_SET_MM_START_CODE, diff --git a/pkg/sentry/syscalls/linux/sys_thread.go b/pkg/sentry/syscalls/linux/sys_thread.go index 0c9e2255d..00915fdde 100644 --- a/pkg/sentry/syscalls/linux/sys_thread.go +++ b/pkg/sentry/syscalls/linux/sys_thread.go @@ -21,6 +21,7 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/fs" + "gvisor.dev/gvisor/pkg/sentry/fsbridge" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/sched" "gvisor.dev/gvisor/pkg/sentry/loader" @@ -119,7 +120,7 @@ func execveat(t *kernel.Task, dirFD int32, pathnameAddr, argvAddr, envvAddr user defer root.DecRef() var wd *fs.Dirent - var executable *fs.File + var executable fsbridge.File var closeOnExec bool if dirFD == linux.AT_FDCWD || path.IsAbs(pathname) { // Even if the pathname is absolute, we may still need the wd @@ -136,7 +137,15 @@ func execveat(t *kernel.Task, dirFD int32, pathnameAddr, argvAddr, envvAddr user closeOnExec = fdFlags.CloseOnExec if atEmptyPath && len(pathname) == 0 { - executable = f + // TODO(gvisor.dev/issue/160): Linux requires only execute permission, + // not read. However, our backing filesystems may prevent us from reading + // the file without read permission. Additionally, a task with a + // non-readable executable has additional constraints on access via + // ptrace and procfs. + if err := f.Dirent.Inode.CheckPermission(t, fs.PermMask{Read: true, Execute: true}); err != nil { + return 0, nil, err + } + executable = fsbridge.NewFSFile(f) } else { wd = f.Dirent wd.IncRef() @@ -152,9 +161,7 @@ func execveat(t *kernel.Task, dirFD int32, pathnameAddr, argvAddr, envvAddr user // Load the new TaskContext. remainingTraversals := uint(linux.MaxSymlinkTraversals) loadArgs := loader.LoadArgs{ - Mounts: t.MountNamespace(), - Root: root, - WorkingDirectory: wd, + Opener: fsbridge.NewFSLookup(t.MountNamespace(), root, wd), RemainingTraversals: &remainingTraversals, ResolveFinal: resolveFinal, Filename: pathname, diff --git a/pkg/sentry/syscalls/linux/vfs2/linux64_override_amd64.go b/pkg/sentry/syscalls/linux/vfs2/linux64_override_amd64.go index c134714ee..e0ac32b33 100644 --- a/pkg/sentry/syscalls/linux/vfs2/linux64_override_amd64.go +++ b/pkg/sentry/syscalls/linux/vfs2/linux64_override_amd64.go @@ -22,4 +22,110 @@ import ( // Override syscall table to add syscalls implementations from this package. func Override(table map[uintptr]kernel.Syscall) { table[0] = syscalls.Supported("read", Read) + + // Remove syscalls that haven't been converted yet. It's better to get ENOSYS + // rather than a SIGSEGV deep in the stack. + delete(table, 1) // write + delete(table, 2) // open + delete(table, 3) // close + delete(table, 4) // stat + delete(table, 5) // fstat + delete(table, 6) // lstat + delete(table, 7) // poll + delete(table, 8) // lseek + delete(table, 9) // mmap + delete(table, 16) // ioctl + delete(table, 17) // pread64 + delete(table, 18) // pwrite64 + delete(table, 19) // readv + delete(table, 20) // writev + delete(table, 21) // access + delete(table, 22) // pipe + delete(table, 32) // dup + delete(table, 33) // dup2 + delete(table, 40) // sendfile + delete(table, 59) // execve + delete(table, 72) // fcntl + delete(table, 73) // flock + delete(table, 74) // fsync + delete(table, 75) // fdatasync + delete(table, 76) // truncate + delete(table, 77) // ftruncate + delete(table, 78) // getdents + delete(table, 79) // getcwd + delete(table, 80) // chdir + delete(table, 81) // fchdir + delete(table, 82) // rename + delete(table, 83) // mkdir + delete(table, 84) // rmdir + delete(table, 85) // creat + delete(table, 86) // link + delete(table, 87) // unlink + delete(table, 88) // symlink + delete(table, 89) // readlink + delete(table, 90) // chmod + delete(table, 91) // fchmod + delete(table, 92) // chown + delete(table, 93) // fchown + delete(table, 94) // lchown + delete(table, 133) // mknod + delete(table, 137) // statfs + delete(table, 138) // fstatfs + delete(table, 161) // chroot + delete(table, 162) // sync + delete(table, 165) // mount + delete(table, 166) // umount2 + delete(table, 172) // iopl + delete(table, 173) // ioperm + delete(table, 187) // readahead + delete(table, 188) // setxattr + delete(table, 189) // lsetxattr + delete(table, 190) // fsetxattr + delete(table, 191) // getxattr + delete(table, 192) // lgetxattr + delete(table, 193) // fgetxattr + delete(table, 206) // io_setup + delete(table, 207) // io_destroy + delete(table, 208) // io_getevents + delete(table, 209) // io_submit + delete(table, 210) // io_cancel + delete(table, 213) // epoll_create + delete(table, 214) // epoll_ctl_old + delete(table, 215) // epoll_wait_old + delete(table, 216) // remap_file_pages + delete(table, 217) // getdents64 + delete(table, 232) // epoll_wait + delete(table, 233) // epoll_ctl + delete(table, 253) // inotify_init + delete(table, 254) // inotify_add_watch + delete(table, 255) // inotify_rm_watch + delete(table, 257) // openat + delete(table, 258) // mkdirat + delete(table, 259) // mknodat + delete(table, 260) // fchownat + delete(table, 261) // futimesat + delete(table, 262) // fstatat + delete(table, 263) // unlinkat + delete(table, 264) // renameat + delete(table, 265) // linkat + delete(table, 266) // symlinkat + delete(table, 267) // readlinkat + delete(table, 268) // fchmodat + delete(table, 269) // faccessat + delete(table, 270) // pselect + delete(table, 271) // ppoll + delete(table, 285) // fallocate + delete(table, 291) // epoll_create1 + delete(table, 292) // dup3 + delete(table, 293) // pipe2 + delete(table, 294) // inotify_init1 + delete(table, 295) // preadv + delete(table, 296) // pwritev + delete(table, 306) // syncfs + delete(table, 316) // renameat2 + delete(table, 319) // memfd_create + delete(table, 322) // execveat + delete(table, 327) // preadv2 + delete(table, 328) // pwritev2 + delete(table, 332) // statx } diff --git a/pkg/sentry/vfs/BUILD b/pkg/sentry/vfs/BUILD index 14b39eb9d..0b4f18ab5 100644 --- a/pkg/sentry/vfs/BUILD +++ b/pkg/sentry/vfs/BUILD @@ -43,6 +43,7 @@ go_library( "//pkg/abi/linux", "//pkg/context", "//pkg/fspath", + "//pkg/log", "//pkg/sentry/arch", "//pkg/sentry/fs/lock", "//pkg/sentry/kernel/auth", diff --git a/pkg/sentry/vfs/context.go b/pkg/sentry/vfs/context.go index d97362b9a..82781e6d3 100644 --- a/pkg/sentry/vfs/context.go +++ b/pkg/sentry/vfs/context.go @@ -29,9 +29,10 @@ const ( CtxRoot ) -// MountNamespaceFromContext returns the MountNamespace used by ctx. It does -// not take a reference on the returned MountNamespace. If ctx is not -// associated with a MountNamespace, MountNamespaceFromContext returns nil. +// MountNamespaceFromContext returns the MountNamespace used by ctx. If ctx is +// not associated with a MountNamespace, MountNamespaceFromContext returns nil. +// +// A reference is taken on the returned MountNamespace. func MountNamespaceFromContext(ctx context.Context) *MountNamespace { if v := ctx.Value(CtxMountNamespace); v != nil { return v.(*MountNamespace) diff --git a/pkg/sentry/vfs/mount.go b/pkg/sentry/vfs/mount.go index 1fbb420f9..ad2c9fcf4 100644 --- a/pkg/sentry/vfs/mount.go +++ b/pkg/sentry/vfs/mount.go @@ -114,6 +114,7 @@ type MountNamespace struct { func (vfs *VirtualFilesystem) NewMountNamespace(ctx context.Context, creds *auth.Credentials, source, fsTypeName string, opts *GetFilesystemOptions) (*MountNamespace, error) { rft := vfs.getFilesystemType(fsTypeName) if rft == nil { + ctx.Warningf("Unknown filesystem: %s", fsTypeName) return nil, syserror.ENODEV } fs, root, err := rft.fsType.GetFilesystem(ctx, vfs, creds, source, *opts) @@ -231,9 +232,12 @@ func (vfs *VirtualFilesystem) UmountAt(ctx context.Context, creds *auth.Credenti return syserror.EINVAL } vfs.mountMu.Lock() - if mntns := MountNamespaceFromContext(ctx); mntns != nil && mntns != vd.mount.ns { - vfs.mountMu.Unlock() - return syserror.EINVAL + if mntns := MountNamespaceFromContext(ctx); mntns != nil { + defer mntns.DecRef() + if mntns != vd.mount.ns { + vfs.mountMu.Unlock() + return syserror.EINVAL + } } // TODO(jamieliu): Linux special-cases umount of the caller's root, which diff --git a/pkg/sentry/vfs/options.go b/pkg/sentry/vfs/options.go index fdf8be157..6af7fdac1 100644 --- a/pkg/sentry/vfs/options.go +++ b/pkg/sentry/vfs/options.go @@ -61,7 +61,7 @@ type MountOptions struct { type OpenOptions struct { // Flags contains access mode and flags as specified for open(2). // - // FilesystemImpls is reponsible for implementing the following flags: + // FilesystemImpls are responsible for implementing the following flags: // O_RDONLY, O_WRONLY, O_RDWR, O_APPEND, O_CREAT, O_DIRECT, O_DSYNC, // O_EXCL, O_NOATIME, O_NOCTTY, O_NONBLOCK, O_PATH, O_SYNC, O_TMPFILE, and // O_TRUNC. VFS is responsible for handling O_DIRECTORY, O_LARGEFILE, and diff --git a/pkg/sentry/vfs/vfs.go b/pkg/sentry/vfs/vfs.go index 9629afee9..51deae313 100644 --- a/pkg/sentry/vfs/vfs.go +++ b/pkg/sentry/vfs/vfs.go @@ -393,7 +393,8 @@ func (vfs *VirtualFilesystem) OpenAt(ctx context.Context, creds *auth.Credential // be executed. return nil, syserror.EACCES } - if linux.FileMode(stat.Mode).FileType() != linux.ModeRegular { + if t := linux.FileMode(stat.Mode).FileType(); t != linux.ModeRegular { + ctx.Infof("%q is not a regular file: %v", pop.Path, t) return nil, syserror.EACCES } } @@ -743,6 +744,8 @@ func (vfs *VirtualFilesystem) SyncAllFilesystems(ctx context.Context) error { // VirtualDentry methods require that a reference is held on the VirtualDentry. // // VirtualDentry is analogous to Linux's struct path. +// +// +stateify savable type VirtualDentry struct { mount *Mount dentry *Dentry diff --git a/runsc/boot/loader.go b/runsc/boot/loader.go index 9f0d5d7af..239ca5302 100644 --- a/runsc/boot/loader.go +++ b/runsc/boot/loader.go @@ -795,16 +795,19 @@ func (l *Loader) executeAsync(args *control.ExecArgs) (kernel.ThreadID, error) { return 0, fmt.Errorf("container %q not started", args.ContainerID) } + // TODO(gvisor.dev/issue/1623): Add VFS2 support + // Get the container MountNamespace from the Task. tg.Leader().WithMuLocked(func(t *kernel.Task) { - // task.MountNamespace() does not take a ref, so we must do so - // ourselves. + // task.MountNamespace() does not take a ref, so we must do so ourselves. args.MountNamespace = t.MountNamespace() args.MountNamespace.IncRef() }) - defer args.MountNamespace.DecRef() + if args.MountNamespace != nil { + defer args.MountNamespace.DecRef() + } - // Add the HOME enviroment varible if it is not already set. + // Add the HOME environment variable if it is not already set. root := args.MountNamespace.Root() defer root.DecRef() ctx := fs.WithRoot(l.k.SupervisorContext(), root) -- cgit v1.2.3 From 10ed60e4778e01a2813eea6e3c201826f75982a5 Mon Sep 17 00:00:00 2001 From: gVisor bot Date: Thu, 20 Feb 2020 09:57:06 -0800 Subject: VFS2: Support memory mapping in tmpfs. tmpfs.fileDescription now implements ConfigureMMap. And tmpfs.regularFile implement memmap.Mappable. The methods are mostly unchanged from VFS1 tmpfs. PiperOrigin-RevId: 296234557 --- pkg/sentry/fsimpl/tmpfs/filesystem.go | 8 +- pkg/sentry/fsimpl/tmpfs/regular_file.go | 233 +++++++++++++++++++++++++++----- pkg/sentry/fsimpl/tmpfs/tmpfs.go | 16 ++- 3 files changed, 213 insertions(+), 44 deletions(-) (limited to 'pkg/sentry/fsimpl/tmpfs/filesystem.go') diff --git a/pkg/sentry/fsimpl/tmpfs/filesystem.go b/pkg/sentry/fsimpl/tmpfs/filesystem.go index 7f7b791c4..e1b551422 100644 --- a/pkg/sentry/fsimpl/tmpfs/filesystem.go +++ b/pkg/sentry/fsimpl/tmpfs/filesystem.go @@ -16,7 +16,6 @@ package tmpfs import ( "fmt" - "sync/atomic" "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/context" @@ -347,10 +346,9 @@ func (d *dentry) open(ctx context.Context, rp *vfs.ResolvingPath, opts *vfs.Open return nil, err } if opts.Flags&linux.O_TRUNC != 0 { - impl.mu.Lock() - impl.data.Truncate(0, impl.memFile) - atomic.StoreUint64(&impl.size, 0) - impl.mu.Unlock() + if _, err := impl.truncate(0); err != nil { + return nil, err + } } return &fd.vfsfd, nil case *directory: diff --git a/pkg/sentry/fsimpl/tmpfs/regular_file.go b/pkg/sentry/fsimpl/tmpfs/regular_file.go index dab346a41..711442424 100644 --- a/pkg/sentry/fsimpl/tmpfs/regular_file.go +++ b/pkg/sentry/fsimpl/tmpfs/regular_file.go @@ -15,6 +15,7 @@ package tmpfs import ( + "fmt" "io" "math" "sync/atomic" @@ -22,6 +23,7 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/safemem" + "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/fs/lock" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" @@ -34,25 +36,53 @@ import ( "gvisor.dev/gvisor/pkg/usermem" ) +// regularFile is a regular (=S_IFREG) tmpfs file. type regularFile struct { inode inode // memFile is a platform.File used to allocate pages to this regularFile. memFile *pgalloc.MemoryFile - // mu protects the fields below. - mu sync.RWMutex + // mapsMu protects mappings. + mapsMu sync.Mutex `state:"nosave"` + + // mappings tracks mappings of the file into memmap.MappingSpaces. + // + // Protected by mapsMu. + mappings memmap.MappingSet + + // writableMappingPages tracks how many pages of virtual memory are mapped + // as potentially writable from this file. If a page has multiple mappings, + // each mapping is counted separately. + // + // This counter is susceptible to overflow as we can potentially count + // mappings from many VMAs. We count pages rather than bytes to slightly + // mitigate this. + // + // Protected by mapsMu. + writableMappingPages uint64 + + // dataMu protects the fields below. + dataMu sync.RWMutex // data maps offsets into the file to offsets into memFile that store // the file's data. + // + // Protected by dataMu. data fsutil.FileRangeSet - // size is the size of data, but accessed using atomic memory - // operations to avoid locking in inode.stat(). - size uint64 - // seals represents file seals on this inode. + // + // Protected by dataMu. seals uint32 + + // size is the size of data. + // + // Protected by both dataMu and inode.mu; reading it requires holding + // either mutex, while writing requires holding both AND using atomics. + // Readers that do not require consistency (like Stat) may read the + // value atomically without holding either lock. + size uint64 } func (fs *filesystem) newRegularFile(creds *auth.Credentials, mode linux.FileMode) *inode { @@ -66,39 +96,170 @@ func (fs *filesystem) newRegularFile(creds *auth.Credentials, mode linux.FileMod // truncate grows or shrinks the file to the given size. It returns true if the // file size was updated. -func (rf *regularFile) truncate(size uint64) (bool, error) { - rf.mu.Lock() - defer rf.mu.Unlock() +func (rf *regularFile) truncate(newSize uint64) (bool, error) { + rf.inode.mu.Lock() + defer rf.inode.mu.Unlock() + return rf.truncateLocked(newSize) +} - if size == rf.size { +// Preconditions: rf.inode.mu must be held. +func (rf *regularFile) truncateLocked(newSize uint64) (bool, error) { + oldSize := rf.size + if newSize == oldSize { // Nothing to do. return false, nil } - if size > rf.size { - // Growing the file. + // Need to hold inode.mu and dataMu while modifying size. + rf.dataMu.Lock() + if newSize > oldSize { + // Can we grow the file? if rf.seals&linux.F_SEAL_GROW != 0 { - // Seal does not allow growth. + rf.dataMu.Unlock() return false, syserror.EPERM } - rf.size = size + // We only need to update the file size. + atomic.StoreUint64(&rf.size, newSize) + rf.dataMu.Unlock() return true, nil } - // Shrinking the file + // We are shrinking the file. First check if this is allowed. if rf.seals&linux.F_SEAL_SHRINK != 0 { - // Seal does not allow shrink. + rf.dataMu.Unlock() return false, syserror.EPERM } - // TODO(gvisor.dev/issues/1197): Invalidate mappings once we have - // mappings. + // Update the file size. + atomic.StoreUint64(&rf.size, newSize) + rf.dataMu.Unlock() + + // Invalidate past translations of truncated pages. + oldpgend := fs.OffsetPageEnd(int64(oldSize)) + newpgend := fs.OffsetPageEnd(int64(newSize)) + if newpgend < oldpgend { + rf.mapsMu.Lock() + rf.mappings.Invalidate(memmap.MappableRange{newpgend, oldpgend}, memmap.InvalidateOpts{ + // Compare Linux's mm/shmem.c:shmem_setattr() => + // mm/memory.c:unmap_mapping_range(evencows=1). + InvalidatePrivate: true, + }) + rf.mapsMu.Unlock() + } - rf.data.Truncate(size, rf.memFile) - rf.size = size + // We are now guaranteed that there are no translations of truncated pages, + // and can remove them. + rf.dataMu.Lock() + rf.data.Truncate(newSize, rf.memFile) + rf.dataMu.Unlock() return true, nil } +// AddMapping implements memmap.Mappable.AddMapping. +func (rf *regularFile) AddMapping(ctx context.Context, ms memmap.MappingSpace, ar usermem.AddrRange, offset uint64, writable bool) error { + rf.mapsMu.Lock() + defer rf.mapsMu.Unlock() + rf.dataMu.RLock() + defer rf.dataMu.RUnlock() + + // Reject writable mapping if F_SEAL_WRITE is set. + if rf.seals&linux.F_SEAL_WRITE != 0 && writable { + return syserror.EPERM + } + + rf.mappings.AddMapping(ms, ar, offset, writable) + if writable { + pagesBefore := rf.writableMappingPages + + // ar is guaranteed to be page aligned per memmap.Mappable. + rf.writableMappingPages += uint64(ar.Length() / usermem.PageSize) + + if rf.writableMappingPages < pagesBefore { + panic(fmt.Sprintf("Overflow while mapping potentially writable pages pointing to a tmpfs file. Before %v, after %v", pagesBefore, rf.writableMappingPages)) + } + } + + return nil +} + +// RemoveMapping implements memmap.Mappable.RemoveMapping. +func (rf *regularFile) RemoveMapping(ctx context.Context, ms memmap.MappingSpace, ar usermem.AddrRange, offset uint64, writable bool) { + rf.mapsMu.Lock() + defer rf.mapsMu.Unlock() + + rf.mappings.RemoveMapping(ms, ar, offset, writable) + + if writable { + pagesBefore := rf.writableMappingPages + + // ar is guaranteed to be page aligned per memmap.Mappable. + rf.writableMappingPages -= uint64(ar.Length() / usermem.PageSize) + + if rf.writableMappingPages > pagesBefore { + panic(fmt.Sprintf("Underflow while unmapping potentially writable pages pointing to a tmpfs file. Before %v, after %v", pagesBefore, rf.writableMappingPages)) + } + } +} + +// CopyMapping implements memmap.Mappable.CopyMapping. +func (rf *regularFile) CopyMapping(ctx context.Context, ms memmap.MappingSpace, srcAR, dstAR usermem.AddrRange, offset uint64, writable bool) error { + return rf.AddMapping(ctx, ms, dstAR, offset, writable) +} + +// Translate implements memmap.Mappable.Translate. +func (rf *regularFile) Translate(ctx context.Context, required, optional memmap.MappableRange, at usermem.AccessType) ([]memmap.Translation, error) { + rf.dataMu.Lock() + defer rf.dataMu.Unlock() + + // Constrain translations to f.attr.Size (rounded up) to prevent + // translation to pages that may be concurrently truncated. + pgend := fs.OffsetPageEnd(int64(rf.size)) + var beyondEOF bool + if required.End > pgend { + if required.Start >= pgend { + return nil, &memmap.BusError{io.EOF} + } + beyondEOF = true + required.End = pgend + } + if optional.End > pgend { + optional.End = pgend + } + + cerr := rf.data.Fill(ctx, required, optional, rf.memFile, usage.Tmpfs, func(_ context.Context, dsts safemem.BlockSeq, _ uint64) (uint64, error) { + // Newly-allocated pages are zeroed, so we don't need to do anything. + return dsts.NumBytes(), nil + }) + + var ts []memmap.Translation + var translatedEnd uint64 + for seg := rf.data.FindSegment(required.Start); seg.Ok() && seg.Start() < required.End; seg, _ = seg.NextNonEmpty() { + segMR := seg.Range().Intersect(optional) + ts = append(ts, memmap.Translation{ + Source: segMR, + File: rf.memFile, + Offset: seg.FileRangeOf(segMR).Start, + Perms: usermem.AnyAccess, + }) + translatedEnd = segMR.End + } + + // Don't return the error returned by f.data.Fill if it occurred outside of + // required. + if translatedEnd < required.End && cerr != nil { + return ts, &memmap.BusError{cerr} + } + if beyondEOF { + return ts, &memmap.BusError{io.EOF} + } + return ts, nil +} + +// InvalidateUnsavable implements memmap.Mappable.InvalidateUnsavable. +func (*regularFile) InvalidateUnsavable(context.Context) error { + return nil +} + type regularFileFD struct { fileDescription @@ -152,8 +313,10 @@ func (fd *regularFileFD) PWrite(ctx context.Context, src usermem.IOSequence, off // Overflow. return 0, syserror.EFBIG } + f.inode.mu.Lock() rw := getRegularFileReadWriter(f, offset) n, err := src.CopyInTo(ctx, rw) + f.inode.mu.Unlock() putRegularFileReadWriter(rw) return n, err } @@ -215,6 +378,12 @@ func (fd *regularFileFD) UnlockPOSIX(ctx context.Context, uid lock.UniqueID, rng return nil } +// ConfigureMMap implements vfs.FileDescriptionImpl.ConfigureMMap. +func (fd *regularFileFD) ConfigureMMap(ctx context.Context, opts *memmap.MMapOpts) error { + file := fd.inode().impl.(*regularFile) + return vfs.GenericConfigureMMap(&fd.vfsfd, file, opts) +} + // regularFileReadWriter implements safemem.Reader and Safemem.Writer. type regularFileReadWriter struct { file *regularFile @@ -244,14 +413,15 @@ func putRegularFileReadWriter(rw *regularFileReadWriter) { // ReadToBlocks implements safemem.Reader.ReadToBlocks. func (rw *regularFileReadWriter) ReadToBlocks(dsts safemem.BlockSeq) (uint64, error) { - rw.file.mu.RLock() + rw.file.dataMu.RLock() + defer rw.file.dataMu.RUnlock() + size := rw.file.size // Compute the range to read (limited by file size and overflow-checked). - if rw.off >= rw.file.size { - rw.file.mu.RUnlock() + if rw.off >= size { return 0, io.EOF } - end := rw.file.size + end := size if rend := rw.off + dsts.NumBytes(); rend > rw.off && rend < end { end = rend } @@ -265,7 +435,6 @@ func (rw *regularFileReadWriter) ReadToBlocks(dsts safemem.BlockSeq) (uint64, er // Get internal mappings. ims, err := rw.file.memFile.MapInternal(seg.FileRangeOf(seg.Range().Intersect(mr)), usermem.Read) if err != nil { - rw.file.mu.RUnlock() return done, err } @@ -275,7 +444,6 @@ func (rw *regularFileReadWriter) ReadToBlocks(dsts safemem.BlockSeq) (uint64, er rw.off += uint64(n) dsts = dsts.DropFirst64(n) if err != nil { - rw.file.mu.RUnlock() return done, err } @@ -291,7 +459,6 @@ func (rw *regularFileReadWriter) ReadToBlocks(dsts safemem.BlockSeq) (uint64, er rw.off += uint64(n) dsts = dsts.DropFirst64(n) if err != nil { - rw.file.mu.RUnlock() return done, err } @@ -299,13 +466,16 @@ func (rw *regularFileReadWriter) ReadToBlocks(dsts safemem.BlockSeq) (uint64, er seg, gap = gap.NextSegment(), fsutil.FileRangeGapIterator{} } } - rw.file.mu.RUnlock() return done, nil } // WriteFromBlocks implements safemem.Writer.WriteFromBlocks. +// +// Preconditions: inode.mu must be held. func (rw *regularFileReadWriter) WriteFromBlocks(srcs safemem.BlockSeq) (uint64, error) { - rw.file.mu.Lock() + // Hold dataMu so we can modify size. + rw.file.dataMu.Lock() + defer rw.file.dataMu.Unlock() // Compute the range to write (overflow-checked). end := rw.off + srcs.NumBytes() @@ -316,7 +486,6 @@ func (rw *regularFileReadWriter) WriteFromBlocks(srcs safemem.BlockSeq) (uint64, // Check if seals prevent either file growth or all writes. switch { case rw.file.seals&linux.F_SEAL_WRITE != 0: // Write sealed - rw.file.mu.Unlock() return 0, syserror.EPERM case end > rw.file.size && rw.file.seals&linux.F_SEAL_GROW != 0: // Grow sealed // When growth is sealed, Linux effectively allows writes which would @@ -338,7 +507,6 @@ func (rw *regularFileReadWriter) WriteFromBlocks(srcs safemem.BlockSeq) (uint64, } if end <= rw.off { // Truncation would result in no data being written. - rw.file.mu.Unlock() return 0, syserror.EPERM } } @@ -395,9 +563,8 @@ exitLoop: // If the write ends beyond the file's previous size, it causes the // file to grow. if rw.off > rw.file.size { - atomic.StoreUint64(&rw.file.size, rw.off) + rw.file.size = rw.off } - rw.file.mu.Unlock() return done, retErr } diff --git a/pkg/sentry/fsimpl/tmpfs/tmpfs.go b/pkg/sentry/fsimpl/tmpfs/tmpfs.go index c5bb17562..521206305 100644 --- a/pkg/sentry/fsimpl/tmpfs/tmpfs.go +++ b/pkg/sentry/fsimpl/tmpfs/tmpfs.go @@ -18,9 +18,10 @@ // Lock order: // // filesystem.mu -// regularFileFD.offMu -// regularFile.mu // inode.mu +// regularFileFD.offMu +// regularFile.mapsMu +// regularFile.dataMu package tmpfs import ( @@ -226,12 +227,15 @@ func (i *inode) tryIncRef() bool { func (i *inode) decRef() { if refs := atomic.AddInt64(&i.refs, -1); refs == 0 { - // This is unnecessary; it's mostly to simulate what tmpfs would do. if regFile, ok := i.impl.(*regularFile); ok { - regFile.mu.Lock() + // Hold inode.mu and regFile.dataMu while mutating + // size. + i.mu.Lock() + regFile.dataMu.Lock() regFile.data.DropAll(regFile.memFile) atomic.StoreUint64(®File.size, 0) - regFile.mu.Unlock() + regFile.dataMu.Unlock() + i.mu.Unlock() } } else if refs < 0 { panic("tmpfs.inode.decRef() called without holding a reference") @@ -320,7 +324,7 @@ func (i *inode) setStat(stat linux.Statx) error { if mask&linux.STATX_SIZE != 0 { switch impl := i.impl.(type) { case *regularFile: - updated, err := impl.truncate(stat.Size) + updated, err := impl.truncateLocked(stat.Size) if err != nil { return err } -- cgit v1.2.3 From 2e38408f20a084de716962d4631e0fec1fd16c16 Mon Sep 17 00:00:00 2001 From: Dean Deng Date: Fri, 13 Mar 2020 11:40:13 -0700 Subject: Implement access/faccessat for VFS2. Note that the raw faccessat system call does not actually take a flags argument; according to faccessat(2), the glibc wrapper implements the flags by using fstatat(2). Remove the flag argument that we try to extract from vfs1, which would just be a garbage value. Updates #1965 Fixes #2101 PiperOrigin-RevId: 300796067 --- pkg/sentry/fsimpl/ext/filesystem.go | 10 ++++++ pkg/sentry/fsimpl/gofer/filesystem.go | 13 ++++++++ pkg/sentry/fsimpl/kernfs/filesystem.go | 14 ++++++++ pkg/sentry/fsimpl/tmpfs/filesystem.go | 12 +++++++ pkg/sentry/syscalls/linux/sys_file.go | 16 ++++++--- pkg/sentry/syscalls/linux/vfs2/stat.go | 60 +++++++++++++++++++++++++++++++--- pkg/sentry/vfs/anonfs.go | 25 +++++++++++--- pkg/sentry/vfs/filesystem.go | 4 +++ pkg/sentry/vfs/vfs.go | 17 ++++++++++ 9 files changed, 157 insertions(+), 14 deletions(-) (limited to 'pkg/sentry/fsimpl/tmpfs/filesystem.go') diff --git a/pkg/sentry/fsimpl/ext/filesystem.go b/pkg/sentry/fsimpl/ext/filesystem.go index e05429d41..8497be615 100644 --- a/pkg/sentry/fsimpl/ext/filesystem.go +++ b/pkg/sentry/fsimpl/ext/filesystem.go @@ -22,6 +22,7 @@ import ( "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fspath" "gvisor.dev/gvisor/pkg/sentry/fsimpl/ext/disklayout" + "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" @@ -255,6 +256,15 @@ func (fs *filesystem) statTo(stat *linux.Statfs) { // TODO(b/134676337): Set Statfs.Flags and Statfs.FSID. } +// AccessAt implements vfs.Filesystem.Impl.AccessAt. +func (fs *filesystem) AccessAt(ctx context.Context, rp *vfs.ResolvingPath, creds *auth.Credentials, ats vfs.AccessTypes) error { + _, inode, err := fs.walk(rp, false) + if err != nil { + return err + } + return inode.checkPermissions(rp.Credentials(), ats) +} + // GetDentryAt implements vfs.FilesystemImpl.GetDentryAt. func (fs *filesystem) GetDentryAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.GetDentryOptions) (*vfs.Dentry, error) { vfsd, inode, err := fs.walk(rp, false) diff --git a/pkg/sentry/fsimpl/gofer/filesystem.go b/pkg/sentry/fsimpl/gofer/filesystem.go index 5cfb0dc4c..38e4cdbc5 100644 --- a/pkg/sentry/fsimpl/gofer/filesystem.go +++ b/pkg/sentry/fsimpl/gofer/filesystem.go @@ -21,6 +21,7 @@ import ( "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fspath" "gvisor.dev/gvisor/pkg/p9" + "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/syserror" ) @@ -499,6 +500,18 @@ func (fs *filesystem) renameMuUnlockAndCheckCaching(ds **[]*dentry) { putDentrySlice(*ds) } +// AccessAt implements vfs.Filesystem.Impl.AccessAt. +func (fs *filesystem) AccessAt(ctx context.Context, rp *vfs.ResolvingPath, creds *auth.Credentials, ats vfs.AccessTypes) error { + var ds *[]*dentry + fs.renameMu.RLock() + defer fs.renameMuRUnlockAndCheckCaching(&ds) + d, err := fs.resolveLocked(ctx, rp, &ds) + if err != nil { + return err + } + return d.checkPermissions(creds, ats, d.isDir()) +} + // GetDentryAt implements vfs.FilesystemImpl.GetDentryAt. func (fs *filesystem) GetDentryAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.GetDentryOptions) (*vfs.Dentry, error) { var ds *[]*dentry diff --git a/pkg/sentry/fsimpl/kernfs/filesystem.go b/pkg/sentry/fsimpl/kernfs/filesystem.go index 1d7e04ad4..3288de290 100644 --- a/pkg/sentry/fsimpl/kernfs/filesystem.go +++ b/pkg/sentry/fsimpl/kernfs/filesystem.go @@ -22,6 +22,7 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fspath" + "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/syserror" ) @@ -229,6 +230,19 @@ func (fs *Filesystem) Sync(ctx context.Context) error { return nil } +// AccessAt implements vfs.Filesystem.Impl.AccessAt. +func (fs *Filesystem) AccessAt(ctx context.Context, rp *vfs.ResolvingPath, creds *auth.Credentials, ats vfs.AccessTypes) error { + fs.mu.RLock() + defer fs.mu.RUnlock() + defer fs.processDeferredDecRefs() + + _, inode, err := fs.walkExistingLocked(ctx, rp) + if err != nil { + return err + } + return inode.CheckPermissions(ctx, creds, ats) +} + // GetDentryAt implements vfs.FilesystemImpl.GetDentryAt. func (fs *Filesystem) GetDentryAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.GetDentryOptions) (*vfs.Dentry, error) { fs.mu.RLock() diff --git a/pkg/sentry/fsimpl/tmpfs/filesystem.go b/pkg/sentry/fsimpl/tmpfs/filesystem.go index e1b551422..02637fca6 100644 --- a/pkg/sentry/fsimpl/tmpfs/filesystem.go +++ b/pkg/sentry/fsimpl/tmpfs/filesystem.go @@ -20,6 +20,7 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fspath" + "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/syserror" ) @@ -154,6 +155,17 @@ func (fs *filesystem) doCreateAt(rp *vfs.ResolvingPath, dir bool, create func(pa return create(parent, name) } +// AccessAt implements vfs.Filesystem.Impl.AccessAt. +func (fs *filesystem) AccessAt(ctx context.Context, rp *vfs.ResolvingPath, creds *auth.Credentials, ats vfs.AccessTypes) error { + fs.mu.RLock() + defer fs.mu.RUnlock() + d, err := resolveLocked(rp) + if err != nil { + return err + } + return d.inode.checkPermissions(creds, ats, d.inode.isDir()) +} + // GetDentryAt implements vfs.FilesystemImpl.GetDentryAt. func (fs *filesystem) GetDentryAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.GetDentryOptions) (*vfs.Dentry, error) { fs.mu.RLock() diff --git a/pkg/sentry/syscalls/linux/sys_file.go b/pkg/sentry/syscalls/linux/sys_file.go index d10a9bed8..35a98212a 100644 --- a/pkg/sentry/syscalls/linux/sys_file.go +++ b/pkg/sentry/syscalls/linux/sys_file.go @@ -514,7 +514,7 @@ func (ac accessContext) Value(key interface{}) interface{} { } } -func accessAt(t *kernel.Task, dirFD int32, addr usermem.Addr, resolve bool, mode uint) error { +func accessAt(t *kernel.Task, dirFD int32, addr usermem.Addr, mode uint) error { const rOK = 4 const wOK = 2 const xOK = 1 @@ -529,7 +529,7 @@ func accessAt(t *kernel.Task, dirFD int32, addr usermem.Addr, resolve bool, mode return syserror.EINVAL } - return fileOpOn(t, dirFD, path, resolve, func(root *fs.Dirent, d *fs.Dirent, _ uint) error { + return fileOpOn(t, dirFD, path, true /* resolve */, func(root *fs.Dirent, d *fs.Dirent, _ uint) error { // access(2) and faccessat(2) check permissions using real // UID/GID, not effective UID/GID. // @@ -564,17 +564,23 @@ func Access(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal addr := args[0].Pointer() mode := args[1].ModeT() - return 0, nil, accessAt(t, linux.AT_FDCWD, addr, true, mode) + return 0, nil, accessAt(t, linux.AT_FDCWD, addr, mode) } // Faccessat implements linux syscall faccessat(2). +// +// Note that the faccessat() system call does not take a flags argument: +// "The raw faccessat() system call takes only the first three arguments. The +// AT_EACCESS and AT_SYMLINK_NOFOLLOW flags are actually implemented within +// the glibc wrapper function for faccessat(). If either of these flags is +// specified, then the wrapper function employs fstatat(2) to determine access +// permissions." - faccessat(2) func Faccessat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { dirFD := args[0].Int() addr := args[1].Pointer() mode := args[2].ModeT() - flags := args[3].Int() - return 0, nil, accessAt(t, dirFD, addr, flags&linux.AT_SYMLINK_NOFOLLOW == 0, mode) + return 0, nil, accessAt(t, dirFD, addr, mode) } // LINT.ThenChange(vfs2/filesystem.go) diff --git a/pkg/sentry/syscalls/linux/vfs2/stat.go b/pkg/sentry/syscalls/linux/vfs2/stat.go index 12c532310..a74ea6fd5 100644 --- a/pkg/sentry/syscalls/linux/vfs2/stat.go +++ b/pkg/sentry/syscalls/linux/vfs2/stat.go @@ -228,14 +228,64 @@ func Readlink(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysc // Access implements Linux syscall access(2). func Access(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { - // FIXME(jamieliu): actually implement - return 0, nil, nil + addr := args[0].Pointer() + mode := args[1].ModeT() + + return 0, nil, accessAt(t, linux.AT_FDCWD, addr, mode) } -// Faccessat implements Linux syscall access(2). +// Faccessat implements Linux syscall faccessat(2). +// +// Note that the faccessat() system call does not take a flags argument: +// "The raw faccessat() system call takes only the first three arguments. The +// AT_EACCESS and AT_SYMLINK_NOFOLLOW flags are actually implemented within +// the glibc wrapper function for faccessat(). If either of these flags is +// specified, then the wrapper function employs fstatat(2) to determine access +// permissions." - faccessat(2) func Faccessat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { - // FIXME(jamieliu): actually implement - return 0, nil, nil + dirfd := args[0].Int() + addr := args[1].Pointer() + mode := args[2].ModeT() + + return 0, nil, accessAt(t, dirfd, addr, mode) +} + +func accessAt(t *kernel.Task, dirfd int32, pathAddr usermem.Addr, mode uint) error { + const rOK = 4 + const wOK = 2 + const xOK = 1 + + // Sanity check the mode. + if mode&^(rOK|wOK|xOK) != 0 { + return syserror.EINVAL + } + + path, err := copyInPath(t, pathAddr) + if err != nil { + return err + } + tpop, err := getTaskPathOperation(t, dirfd, path, disallowEmptyPath, followFinalSymlink) + if err != nil { + return err + } + + // access(2) and faccessat(2) check permissions using real + // UID/GID, not effective UID/GID. + // + // "access() needs to use the real uid/gid, not the effective + // uid/gid. We do this by temporarily clearing all FS-related + // capabilities and switching the fsuid/fsgid around to the + // real ones." -fs/open.c:faccessat + creds := t.Credentials().Fork() + creds.EffectiveKUID = creds.RealKUID + creds.EffectiveKGID = creds.RealKGID + if creds.EffectiveKUID.In(creds.UserNamespace) == auth.RootUID { + creds.EffectiveCaps = creds.PermittedCaps + } else { + creds.EffectiveCaps = 0 + } + + return t.Kernel().VFS().AccessAt(t, creds, vfs.AccessTypes(mode), &tpop.pop) } // Readlinkat implements Linux syscall mknodat(2). diff --git a/pkg/sentry/vfs/anonfs.go b/pkg/sentry/vfs/anonfs.go index 2db25be49..925996517 100644 --- a/pkg/sentry/vfs/anonfs.go +++ b/pkg/sentry/vfs/anonfs.go @@ -41,7 +41,14 @@ func (vfs *VirtualFilesystem) NewAnonVirtualDentry(name string) VirtualDentry { } } -const anonfsBlockSize = usermem.PageSize // via fs/libfs.c:pseudo_fs_fill_super() +const ( + anonfsBlockSize = usermem.PageSize // via fs/libfs.c:pseudo_fs_fill_super() + + // Mode, UID, and GID for a generic anonfs file. + anonFileMode = 0600 // no type is correct + anonFileUID = auth.RootKUID + anonFileGID = auth.RootKGID +) // anonFilesystem is the implementation of FilesystemImpl that backs // VirtualDentries returned by VirtualFilesystem.NewAnonVirtualDentry(). @@ -69,6 +76,16 @@ func (fs *anonFilesystem) Sync(ctx context.Context) error { return nil } +// AccessAt implements vfs.Filesystem.Impl.AccessAt. +// +// TODO(gvisor.dev/issue/1965): Implement access permissions. +func (fs *anonFilesystem) AccessAt(ctx context.Context, rp *ResolvingPath, creds *auth.Credentials, ats AccessTypes) error { + if !rp.Done() { + return syserror.ENOTDIR + } + return GenericCheckPermissions(creds, ats, false /* isDir */, anonFileMode, anonFileUID, anonFileGID) +} + // GetDentryAt implements FilesystemImpl.GetDentryAt. func (fs *anonFilesystem) GetDentryAt(ctx context.Context, rp *ResolvingPath, opts GetDentryOptions) (*Dentry, error) { if !rp.Done() { @@ -167,9 +184,9 @@ func (fs *anonFilesystem) StatAt(ctx context.Context, rp *ResolvingPath, opts St Mask: linux.STATX_TYPE | linux.STATX_MODE | linux.STATX_NLINK | linux.STATX_UID | linux.STATX_GID | linux.STATX_INO | linux.STATX_SIZE | linux.STATX_BLOCKS, Blksize: anonfsBlockSize, Nlink: 1, - UID: uint32(auth.RootKUID), - GID: uint32(auth.RootKGID), - Mode: 0600, // no type is correct + UID: uint32(anonFileUID), + GID: uint32(anonFileGID), + Mode: anonFileMode, Ino: 1, Size: 0, Blocks: 0, diff --git a/pkg/sentry/vfs/filesystem.go b/pkg/sentry/vfs/filesystem.go index 556976d0b..c43dcff3d 100644 --- a/pkg/sentry/vfs/filesystem.go +++ b/pkg/sentry/vfs/filesystem.go @@ -20,6 +20,7 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fspath" + "gvisor.dev/gvisor/pkg/sentry/kernel/auth" ) // A Filesystem is a tree of nodes represented by Dentries, which forms part of @@ -144,6 +145,9 @@ type FilesystemImpl interface { // file data to be written to the underlying [filesystem]", as by syncfs(2). Sync(ctx context.Context) error + // AccessAt checks whether a user with creds can access the file at rp. + AccessAt(ctx context.Context, rp *ResolvingPath, creds *auth.Credentials, ats AccessTypes) error + // GetDentryAt returns a Dentry representing the file at rp. A reference is // taken on the returned Dentry. // diff --git a/pkg/sentry/vfs/vfs.go b/pkg/sentry/vfs/vfs.go index 365e8b30d..2e2880171 100644 --- a/pkg/sentry/vfs/vfs.go +++ b/pkg/sentry/vfs/vfs.go @@ -174,6 +174,23 @@ type PathOperation struct { FollowFinalSymlink bool } +// AccessAt checks whether a user with creds has access to the file at +// the given path. +func (vfs *VirtualFilesystem) AccessAt(ctx context.Context, creds *auth.Credentials, ats AccessTypes, pop *PathOperation) error { + rp := vfs.getResolvingPath(creds, pop) + for { + err := rp.mount.fs.impl.AccessAt(ctx, rp, creds, ats) + if err == nil { + vfs.putResolvingPath(rp) + return nil + } + if !rp.handleError(err) { + vfs.putResolvingPath(rp) + return err + } + } +} + // GetDentryAt returns a VirtualDentry representing the given path, at which a // file must exist. A reference is taken on the returned VirtualDentry. func (vfs *VirtualFilesystem) GetDentryAt(ctx context.Context, creds *auth.Credentials, pop *PathOperation, opts *GetDentryOptions) (VirtualDentry, error) { -- cgit v1.2.3 From 0f60799a4f8c3db567973574147370fc900df55f Mon Sep 17 00:00:00 2001 From: Fabricio Voznika Date: Mon, 16 Mar 2020 13:28:00 -0700 Subject: Add calls to vfs.CheckSetStat to fsimpls Only gofer filesystem was calling vfs.CheckSetStat for vfs.FilesystemImpl.SetStatAt and vfs.FileDescriptionImpl.SetStat. Updates #1193, #1672, #1197 PiperOrigin-RevId: 301226522 --- pkg/sentry/fsimpl/host/host.go | 16 +++++++++++----- pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go | 2 +- pkg/sentry/fsimpl/kernfs/fd_impl_util.go | 4 +++- pkg/sentry/fsimpl/kernfs/filesystem.go | 2 +- pkg/sentry/fsimpl/kernfs/inode_impl_util.go | 14 ++++++++++++-- pkg/sentry/fsimpl/kernfs/kernfs.go | 6 ++++-- pkg/sentry/fsimpl/kernfs/kernfs_test.go | 2 +- pkg/sentry/fsimpl/kernfs/symlink.go | 2 +- pkg/sentry/fsimpl/proc/subtasks.go | 3 ++- pkg/sentry/fsimpl/proc/task.go | 2 +- pkg/sentry/fsimpl/proc/tasks_files.go | 8 ++++---- pkg/sentry/fsimpl/sys/sys.go | 2 +- pkg/sentry/fsimpl/tmpfs/filesystem.go | 2 +- pkg/sentry/fsimpl/tmpfs/tmpfs.go | 11 +++++++++-- pkg/sentry/vfs/file_description.go | 3 ++- pkg/sentry/vfs/filesystem.go | 4 +++- 16 files changed, 57 insertions(+), 26 deletions(-) (limited to 'pkg/sentry/fsimpl/tmpfs/filesystem.go') diff --git a/pkg/sentry/fsimpl/host/host.go b/pkg/sentry/fsimpl/host/host.go index 0be812d13..67c050c30 100644 --- a/pkg/sentry/fsimpl/host/host.go +++ b/pkg/sentry/fsimpl/host/host.go @@ -114,7 +114,8 @@ type inode struct { ino uint64 // mu protects the inode metadata below. - mu sync.Mutex + // TODO(gvisor.dev/issue/1672): actually protect fields below. + //mu sync.Mutex // mode is the file mode of this inode. Note that this value may become out // of date if the mode is changed on the host, e.g. with chmod. @@ -269,16 +270,20 @@ func (i *inode) fstat(opts vfs.StatOptions) (linux.Statx, error) { } // SetStat implements kernfs.Inode. -func (i *inode) SetStat(_ *vfs.Filesystem, opts vfs.SetStatOptions) error { +func (i *inode) SetStat(fs *vfs.Filesystem, creds *auth.Credentials, opts vfs.SetStatOptions) error { s := opts.Stat m := s.Mask if m == 0 { return nil } - if m&(linux.STATX_UID|linux.STATX_GID) != 0 { + if m&^(linux.STATX_MODE|linux.STATX_SIZE|linux.STATX_ATIME|linux.STATX_MTIME) != 0 { return syserror.EPERM } + if err := vfs.CheckSetStat(creds, &s, uint16(i.Mode().Permissions()), i.uid, i.gid); err != nil { + return err + } + if m&linux.STATX_MODE != 0 { if err := syscall.Fchmod(i.hostFD, uint32(s.Mode)); err != nil { return err @@ -375,8 +380,9 @@ type fileDescription struct { } // SetStat implements vfs.FileDescriptionImpl. -func (f *fileDescription) SetStat(_ context.Context, opts vfs.SetStatOptions) error { - return f.inode.SetStat(nil, opts) +func (f *fileDescription) SetStat(ctx context.Context, opts vfs.SetStatOptions) error { + creds := auth.CredentialsFromContext(ctx) + return f.inode.SetStat(nil, creds, opts) } // Stat implements vfs.FileDescriptionImpl. diff --git a/pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go b/pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go index 0d27a8867..c788d1d62 100644 --- a/pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go +++ b/pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go @@ -64,7 +64,7 @@ func (f *DynamicBytesFile) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vf // SetStat implements Inode.SetStat. By default DynamicBytesFile doesn't allow // inode attributes to be changed. Override SetStat() making it call // f.InodeAttrs to allow it. -func (*DynamicBytesFile) SetStat(*vfs.Filesystem, vfs.SetStatOptions) error { +func (*DynamicBytesFile) SetStat(*vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error { return syserror.EPERM } diff --git a/pkg/sentry/fsimpl/kernfs/fd_impl_util.go b/pkg/sentry/fsimpl/kernfs/fd_impl_util.go index da821d524..331c82011 100644 --- a/pkg/sentry/fsimpl/kernfs/fd_impl_util.go +++ b/pkg/sentry/fsimpl/kernfs/fd_impl_util.go @@ -17,6 +17,7 @@ package kernfs import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/syserror" @@ -206,6 +207,7 @@ func (fd *GenericDirectoryFD) Stat(ctx context.Context, opts vfs.StatOptions) (l // SetStat implements vfs.FileDescriptionImpl.SetStat. func (fd *GenericDirectoryFD) SetStat(ctx context.Context, opts vfs.SetStatOptions) error { fs := fd.filesystem() + creds := auth.CredentialsFromContext(ctx) inode := fd.vfsfd.VirtualDentry().Dentry().Impl().(*Dentry).inode - return inode.SetStat(fs, opts) + return inode.SetStat(fs, creds, opts) } diff --git a/pkg/sentry/fsimpl/kernfs/filesystem.go b/pkg/sentry/fsimpl/kernfs/filesystem.go index 3288de290..37fbe2eea 100644 --- a/pkg/sentry/fsimpl/kernfs/filesystem.go +++ b/pkg/sentry/fsimpl/kernfs/filesystem.go @@ -636,7 +636,7 @@ func (fs *Filesystem) SetStatAt(ctx context.Context, rp *vfs.ResolvingPath, opts if opts.Stat.Mask == 0 { return nil } - return inode.SetStat(fs.VFSFilesystem(), opts) + return inode.SetStat(fs.VFSFilesystem(), rp.Credentials(), opts) } // StatAt implements vfs.FilesystemImpl.StatAt. diff --git a/pkg/sentry/fsimpl/kernfs/inode_impl_util.go b/pkg/sentry/fsimpl/kernfs/inode_impl_util.go index 4ed41326d..851c61b49 100644 --- a/pkg/sentry/fsimpl/kernfs/inode_impl_util.go +++ b/pkg/sentry/fsimpl/kernfs/inode_impl_util.go @@ -234,7 +234,17 @@ func (a *InodeAttrs) Stat(*vfs.Filesystem, vfs.StatOptions) (linux.Statx, error) } // SetStat implements Inode.SetStat. -func (a *InodeAttrs) SetStat(_ *vfs.Filesystem, opts vfs.SetStatOptions) error { +func (a *InodeAttrs) SetStat(fs *vfs.Filesystem, creds *auth.Credentials, opts vfs.SetStatOptions) error { + if opts.Stat.Mask == 0 { + return nil + } + if opts.Stat.Mask&^(linux.STATX_MODE|linux.STATX_UID|linux.STATX_GID) != 0 { + return syserror.EPERM + } + if err := vfs.CheckSetStat(creds, &opts.Stat, uint16(a.Mode().Permissions()), auth.KUID(atomic.LoadUint32(&a.uid)), auth.KGID(atomic.LoadUint32(&a.gid))); err != nil { + return err + } + stat := opts.Stat if stat.Mask&linux.STATX_MODE != 0 { for { @@ -556,7 +566,7 @@ func (s *StaticDirectory) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs } // SetStat implements Inode.SetStat not allowing inode attributes to be changed. -func (*StaticDirectory) SetStat(*vfs.Filesystem, vfs.SetStatOptions) error { +func (*StaticDirectory) SetStat(*vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error { return syserror.EPERM } diff --git a/pkg/sentry/fsimpl/kernfs/kernfs.go b/pkg/sentry/fsimpl/kernfs/kernfs.go index 18a34a590..b12b216d2 100644 --- a/pkg/sentry/fsimpl/kernfs/kernfs.go +++ b/pkg/sentry/fsimpl/kernfs/kernfs.go @@ -330,8 +330,10 @@ type inodeMetadata interface { Stat(fs *vfs.Filesystem, opts vfs.StatOptions) (linux.Statx, error) // SetStat updates the metadata for this inode. This corresponds to - // vfs.FilesystemImpl.SetStatAt. - SetStat(fs *vfs.Filesystem, opts vfs.SetStatOptions) error + // vfs.FilesystemImpl.SetStatAt. Implementations are responsible for checking + // if the operation can be performed (see vfs.CheckSetStat() for common + // checks). + SetStat(fs *vfs.Filesystem, creds *auth.Credentials, opts vfs.SetStatOptions) error } // Precondition: All methods in this interface may only be called on directory diff --git a/pkg/sentry/fsimpl/kernfs/kernfs_test.go b/pkg/sentry/fsimpl/kernfs/kernfs_test.go index 0459fb305..2875e6ffa 100644 --- a/pkg/sentry/fsimpl/kernfs/kernfs_test.go +++ b/pkg/sentry/fsimpl/kernfs/kernfs_test.go @@ -91,7 +91,7 @@ type attrs struct { kernfs.InodeAttrs } -func (a *attrs) SetStat(fs *vfs.Filesystem, opt vfs.SetStatOptions) error { +func (*attrs) SetStat(*vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error { return syserror.EPERM } diff --git a/pkg/sentry/fsimpl/kernfs/symlink.go b/pkg/sentry/fsimpl/kernfs/symlink.go index 41c5a3099..92f709d29 100644 --- a/pkg/sentry/fsimpl/kernfs/symlink.go +++ b/pkg/sentry/fsimpl/kernfs/symlink.go @@ -56,6 +56,6 @@ func (s *StaticSymlink) Readlink(_ context.Context) (string, error) { } // SetStat implements Inode.SetStat not allowing inode attributes to be changed. -func (*StaticSymlink) SetStat(*vfs.Filesystem, vfs.SetStatOptions) error { +func (*StaticSymlink) SetStat(*vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error { return syserror.EPERM } diff --git a/pkg/sentry/fsimpl/proc/subtasks.go b/pkg/sentry/fsimpl/proc/subtasks.go index ea6d60f6e..eb191aba4 100644 --- a/pkg/sentry/fsimpl/proc/subtasks.go +++ b/pkg/sentry/fsimpl/proc/subtasks.go @@ -22,6 +22,7 @@ import ( "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs" "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/syserror" ) @@ -129,6 +130,6 @@ func (i *subtasksInode) Stat(vsfs *vfs.Filesystem, opts vfs.StatOptions) (linux. } // SetStat implements Inode.SetStat not allowing inode attributes to be changed. -func (*subtasksInode) SetStat(*vfs.Filesystem, vfs.SetStatOptions) error { +func (*subtasksInode) SetStat(*vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error { return syserror.EPERM } diff --git a/pkg/sentry/fsimpl/proc/task.go b/pkg/sentry/fsimpl/proc/task.go index fae3fc5aa..ceb427ffb 100644 --- a/pkg/sentry/fsimpl/proc/task.go +++ b/pkg/sentry/fsimpl/proc/task.go @@ -108,7 +108,7 @@ func (i *taskInode) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenO } // SetStat implements Inode.SetStat not allowing inode attributes to be changed. -func (*taskInode) SetStat(*vfs.Filesystem, vfs.SetStatOptions) error { +func (*taskInode) SetStat(*vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error { return syserror.EPERM } diff --git a/pkg/sentry/fsimpl/proc/tasks_files.go b/pkg/sentry/fsimpl/proc/tasks_files.go index 20085bb39..d3d99393f 100644 --- a/pkg/sentry/fsimpl/proc/tasks_files.go +++ b/pkg/sentry/fsimpl/proc/tasks_files.go @@ -64,7 +64,7 @@ func (s *selfSymlink) Readlink(ctx context.Context) (string, error) { } // SetStat implements Inode.SetStat not allowing inode attributes to be changed. -func (*selfSymlink) SetStat(*vfs.Filesystem, vfs.SetStatOptions) error { +func (*selfSymlink) SetStat(*vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error { return syserror.EPERM } @@ -102,7 +102,7 @@ func (s *threadSelfSymlink) Readlink(ctx context.Context) (string, error) { } // SetStat implements Inode.SetStat not allowing inode attributes to be changed. -func (*threadSelfSymlink) SetStat(*vfs.Filesystem, vfs.SetStatOptions) error { +func (*threadSelfSymlink) SetStat(*vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error { return syserror.EPERM } @@ -114,8 +114,8 @@ type dynamicBytesFileSetAttr struct { } // SetStat implements Inode.SetStat. -func (d *dynamicBytesFileSetAttr) SetStat(fs *vfs.Filesystem, opts vfs.SetStatOptions) error { - return d.DynamicBytesFile.InodeAttrs.SetStat(fs, opts) +func (d *dynamicBytesFileSetAttr) SetStat(fs *vfs.Filesystem, creds *auth.Credentials, opts vfs.SetStatOptions) error { + return d.DynamicBytesFile.InodeAttrs.SetStat(fs, creds, opts) } // cpuStats contains the breakdown of CPU time for /proc/stat. diff --git a/pkg/sentry/fsimpl/sys/sys.go b/pkg/sentry/fsimpl/sys/sys.go index 3928ff2c8..9c8e63783 100644 --- a/pkg/sentry/fsimpl/sys/sys.go +++ b/pkg/sentry/fsimpl/sys/sys.go @@ -95,7 +95,7 @@ func (fs *filesystem) newDir(creds *auth.Credentials, mode linux.FileMode, conte } // SetStat implements Inode.SetStat not allowing inode attributes to be changed. -func (*dir) SetStat(*vfs.Filesystem, vfs.SetStatOptions) error { +func (*dir) SetStat(*vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error { return syserror.EPERM } diff --git a/pkg/sentry/fsimpl/tmpfs/filesystem.go b/pkg/sentry/fsimpl/tmpfs/filesystem.go index 02637fca6..6e8b4cae7 100644 --- a/pkg/sentry/fsimpl/tmpfs/filesystem.go +++ b/pkg/sentry/fsimpl/tmpfs/filesystem.go @@ -575,7 +575,7 @@ func (fs *filesystem) SetStatAt(ctx context.Context, rp *vfs.ResolvingPath, opts if err != nil { return err } - return d.inode.setStat(opts.Stat) + return d.inode.setStat(rp.Credentials(), &opts.Stat) } // StatAt implements vfs.FilesystemImpl.StatAt. diff --git a/pkg/sentry/fsimpl/tmpfs/tmpfs.go b/pkg/sentry/fsimpl/tmpfs/tmpfs.go index 521206305..c18f1e46e 100644 --- a/pkg/sentry/fsimpl/tmpfs/tmpfs.go +++ b/pkg/sentry/fsimpl/tmpfs/tmpfs.go @@ -299,10 +299,16 @@ func (i *inode) statTo(stat *linux.Statx) { } } -func (i *inode) setStat(stat linux.Statx) error { +func (i *inode) setStat(creds *auth.Credentials, stat *linux.Statx) error { if stat.Mask == 0 { return nil } + if stat.Mask&^(linux.STATX_MODE|linux.STATX_UID|linux.STATX_GID|linux.STATX_ATIME|linux.STATX_MTIME|linux.STATX_CTIME|linux.STATX_SIZE) != 0 { + return syserror.EPERM + } + if err := vfs.CheckSetStat(creds, stat, uint16(atomic.LoadUint32(&i.mode))&^linux.S_IFMT, auth.KUID(atomic.LoadUint32(&i.uid)), auth.KGID(atomic.LoadUint32(&i.gid))); err != nil { + return err + } i.mu.Lock() var ( needsMtimeBump bool @@ -457,5 +463,6 @@ func (fd *fileDescription) Stat(ctx context.Context, opts vfs.StatOptions) (linu // SetStat implements vfs.FileDescriptionImpl.SetStat. func (fd *fileDescription) SetStat(ctx context.Context, opts vfs.SetStatOptions) error { - return fd.inode().setStat(opts.Stat) + creds := auth.CredentialsFromContext(ctx) + return fd.inode().setStat(creds, &opts.Stat) } diff --git a/pkg/sentry/vfs/file_description.go b/pkg/sentry/vfs/file_description.go index 9a1ad630c..8ee549dc2 100644 --- a/pkg/sentry/vfs/file_description.go +++ b/pkg/sentry/vfs/file_description.go @@ -286,7 +286,8 @@ type FileDescriptionImpl interface { Stat(ctx context.Context, opts StatOptions) (linux.Statx, error) // SetStat updates metadata for the file represented by the - // FileDescription. + // FileDescription. Implementations are responsible for checking if the + // operation can be performed (see vfs.CheckSetStat() for common checks). SetStat(ctx context.Context, opts SetStatOptions) error // StatFS returns metadata for the filesystem containing the file diff --git a/pkg/sentry/vfs/filesystem.go b/pkg/sentry/vfs/filesystem.go index c43dcff3d..332decce6 100644 --- a/pkg/sentry/vfs/filesystem.go +++ b/pkg/sentry/vfs/filesystem.go @@ -366,7 +366,9 @@ type FilesystemImpl interface { // ResolvingPath.Resolve*(), then !rp.Done(). RmdirAt(ctx context.Context, rp *ResolvingPath) error - // SetStatAt updates metadata for the file at the given path. + // SetStatAt updates metadata for the file at the given path. Implementations + // are responsible for checking if the operation can be performed + // (see vfs.CheckSetStat() for common checks). // // Errors: // -- cgit v1.2.3 From 2a6c4369be8d0522a1f439aa02bce0eb21d42ea2 Mon Sep 17 00:00:00 2001 From: Fabricio Voznika Date: Mon, 16 Mar 2020 15:59:29 -0700 Subject: Enforce file size rlimits in VFS2 Updates #1035 PiperOrigin-RevId: 301255357 --- pkg/sentry/fsimpl/gofer/gofer.go | 2 +- pkg/sentry/fsimpl/gofer/regular_file.go | 5 ++++ pkg/sentry/fsimpl/gofer/special_file.go | 8 +++++++ pkg/sentry/fsimpl/host/default_file.go | 7 +++++- pkg/sentry/fsimpl/host/host.go | 6 ++--- pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go | 2 +- pkg/sentry/fsimpl/kernfs/fd_impl_util.go | 2 +- pkg/sentry/fsimpl/kernfs/filesystem.go | 2 +- pkg/sentry/fsimpl/kernfs/inode_impl_util.go | 6 ++--- pkg/sentry/fsimpl/kernfs/kernfs.go | 2 +- pkg/sentry/fsimpl/kernfs/kernfs_test.go | 2 +- pkg/sentry/fsimpl/kernfs/symlink.go | 2 +- pkg/sentry/fsimpl/proc/subtasks.go | 2 +- pkg/sentry/fsimpl/proc/task.go | 2 +- pkg/sentry/fsimpl/proc/tasks_files.go | 8 +++---- pkg/sentry/fsimpl/sys/sys.go | 2 +- pkg/sentry/fsimpl/tmpfs/filesystem.go | 2 +- pkg/sentry/fsimpl/tmpfs/regular_file.go | 11 +++++++-- pkg/sentry/fsimpl/tmpfs/tmpfs.go | 6 ++--- pkg/sentry/syscalls/linux/vfs2/setstat.go | 15 ++++++++++-- pkg/sentry/vfs/BUILD | 1 + pkg/sentry/vfs/file_description_impl_util.go | 5 ++++ pkg/sentry/vfs/permissions.go | 33 +++++++++++++++++++++++++- 23 files changed, 103 insertions(+), 30 deletions(-) (limited to 'pkg/sentry/fsimpl/tmpfs/filesystem.go') diff --git a/pkg/sentry/fsimpl/gofer/gofer.go b/pkg/sentry/fsimpl/gofer/gofer.go index c4a8f0b38..999485492 100644 --- a/pkg/sentry/fsimpl/gofer/gofer.go +++ b/pkg/sentry/fsimpl/gofer/gofer.go @@ -713,7 +713,7 @@ func (d *dentry) setStat(ctx context.Context, creds *auth.Credentials, stat *lin if stat.Mask&^(linux.STATX_MODE|linux.STATX_UID|linux.STATX_GID|linux.STATX_ATIME|linux.STATX_MTIME|linux.STATX_SIZE) != 0 { return syserror.EPERM } - if err := vfs.CheckSetStat(creds, stat, uint16(atomic.LoadUint32(&d.mode))&^linux.S_IFMT, auth.KUID(atomic.LoadUint32(&d.uid)), auth.KGID(atomic.LoadUint32(&d.gid))); err != nil { + if err := vfs.CheckSetStat(ctx, creds, stat, uint16(atomic.LoadUint32(&d.mode))&^linux.S_IFMT, auth.KUID(atomic.LoadUint32(&d.uid)), auth.KGID(atomic.LoadUint32(&d.gid))); err != nil { return err } if err := mnt.CheckBeginWrite(); err != nil { diff --git a/pkg/sentry/fsimpl/gofer/regular_file.go b/pkg/sentry/fsimpl/gofer/regular_file.go index e95209661..3593eb1d5 100644 --- a/pkg/sentry/fsimpl/gofer/regular_file.go +++ b/pkg/sentry/fsimpl/gofer/regular_file.go @@ -126,6 +126,11 @@ func (fd *regularFileFD) PWrite(ctx context.Context, src usermem.IOSequence, off if opts.Flags != 0 { return 0, syserror.EOPNOTSUPP } + limit, err := vfs.CheckLimit(ctx, offset, src.NumBytes()) + if err != nil { + return 0, err + } + src = src.TakeFirst64(limit) d := fd.dentry() d.metadataMu.Lock() diff --git a/pkg/sentry/fsimpl/gofer/special_file.go b/pkg/sentry/fsimpl/gofer/special_file.go index 08c691c47..274f7346f 100644 --- a/pkg/sentry/fsimpl/gofer/special_file.go +++ b/pkg/sentry/fsimpl/gofer/special_file.go @@ -107,6 +107,14 @@ func (fd *specialFileFD) PWrite(ctx context.Context, src usermem.IOSequence, off return 0, syserror.EOPNOTSUPP } + if fd.dentry().fileType() == linux.S_IFREG { + limit, err := vfs.CheckLimit(ctx, offset, src.NumBytes()) + if err != nil { + return 0, err + } + src = src.TakeFirst64(limit) + } + // Do a buffered write. See rationale in PRead. if d := fd.dentry(); d.fs.opts.interop != InteropModeShared { d.touchCMtime(ctx) diff --git a/pkg/sentry/fsimpl/host/default_file.go b/pkg/sentry/fsimpl/host/default_file.go index 98682ba5e..459238603 100644 --- a/pkg/sentry/fsimpl/host/default_file.go +++ b/pkg/sentry/fsimpl/host/default_file.go @@ -112,7 +112,6 @@ func (f *defaultFileFD) PWrite(ctx context.Context, src usermem.IOSequence, offs if f.inode.isStream { return 0, syserror.ESPIPE } - return writeToHostFD(ctx, f.inode.hostFD, src, offset, int(opts.Flags)) } @@ -146,6 +145,12 @@ func writeToHostFD(ctx context.Context, hostFD int, src usermem.IOSequence, offs return 0, syserror.EOPNOTSUPP } + limit, err := vfs.CheckLimit(ctx, offset, src.NumBytes()) + if err != nil { + return 0, err + } + src = src.TakeFirst64(limit) + var writer safemem.Writer if offset == -1 { writer = safemem.FromIOWriter{fd.NewReadWriter(hostFD)} diff --git a/pkg/sentry/fsimpl/host/host.go b/pkg/sentry/fsimpl/host/host.go index 67c050c30..2eebcd60c 100644 --- a/pkg/sentry/fsimpl/host/host.go +++ b/pkg/sentry/fsimpl/host/host.go @@ -270,7 +270,7 @@ func (i *inode) fstat(opts vfs.StatOptions) (linux.Statx, error) { } // SetStat implements kernfs.Inode. -func (i *inode) SetStat(fs *vfs.Filesystem, creds *auth.Credentials, opts vfs.SetStatOptions) error { +func (i *inode) SetStat(ctx context.Context, fs *vfs.Filesystem, creds *auth.Credentials, opts vfs.SetStatOptions) error { s := opts.Stat m := s.Mask @@ -280,7 +280,7 @@ func (i *inode) SetStat(fs *vfs.Filesystem, creds *auth.Credentials, opts vfs.Se if m&^(linux.STATX_MODE|linux.STATX_SIZE|linux.STATX_ATIME|linux.STATX_MTIME) != 0 { return syserror.EPERM } - if err := vfs.CheckSetStat(creds, &s, uint16(i.Mode().Permissions()), i.uid, i.gid); err != nil { + if err := vfs.CheckSetStat(ctx, creds, &s, uint16(i.Mode().Permissions()), i.uid, i.gid); err != nil { return err } @@ -382,7 +382,7 @@ type fileDescription struct { // SetStat implements vfs.FileDescriptionImpl. func (f *fileDescription) SetStat(ctx context.Context, opts vfs.SetStatOptions) error { creds := auth.CredentialsFromContext(ctx) - return f.inode.SetStat(nil, creds, opts) + return f.inode.SetStat(ctx, nil, creds, opts) } // Stat implements vfs.FileDescriptionImpl. diff --git a/pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go b/pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go index c788d1d62..d8bddbafa 100644 --- a/pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go +++ b/pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go @@ -64,7 +64,7 @@ func (f *DynamicBytesFile) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vf // SetStat implements Inode.SetStat. By default DynamicBytesFile doesn't allow // inode attributes to be changed. Override SetStat() making it call // f.InodeAttrs to allow it. -func (*DynamicBytesFile) SetStat(*vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error { +func (*DynamicBytesFile) SetStat(context.Context, *vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error { return syserror.EPERM } diff --git a/pkg/sentry/fsimpl/kernfs/fd_impl_util.go b/pkg/sentry/fsimpl/kernfs/fd_impl_util.go index 331c82011..75c4bab1a 100644 --- a/pkg/sentry/fsimpl/kernfs/fd_impl_util.go +++ b/pkg/sentry/fsimpl/kernfs/fd_impl_util.go @@ -209,5 +209,5 @@ func (fd *GenericDirectoryFD) SetStat(ctx context.Context, opts vfs.SetStatOptio fs := fd.filesystem() creds := auth.CredentialsFromContext(ctx) inode := fd.vfsfd.VirtualDentry().Dentry().Impl().(*Dentry).inode - return inode.SetStat(fs, creds, opts) + return inode.SetStat(ctx, fs, creds, opts) } diff --git a/pkg/sentry/fsimpl/kernfs/filesystem.go b/pkg/sentry/fsimpl/kernfs/filesystem.go index 37fbe2eea..31da8b511 100644 --- a/pkg/sentry/fsimpl/kernfs/filesystem.go +++ b/pkg/sentry/fsimpl/kernfs/filesystem.go @@ -636,7 +636,7 @@ func (fs *Filesystem) SetStatAt(ctx context.Context, rp *vfs.ResolvingPath, opts if opts.Stat.Mask == 0 { return nil } - return inode.SetStat(fs.VFSFilesystem(), rp.Credentials(), opts) + return inode.SetStat(ctx, fs.VFSFilesystem(), rp.Credentials(), opts) } // StatAt implements vfs.FilesystemImpl.StatAt. diff --git a/pkg/sentry/fsimpl/kernfs/inode_impl_util.go b/pkg/sentry/fsimpl/kernfs/inode_impl_util.go index 851c61b49..c612dcf07 100644 --- a/pkg/sentry/fsimpl/kernfs/inode_impl_util.go +++ b/pkg/sentry/fsimpl/kernfs/inode_impl_util.go @@ -234,14 +234,14 @@ func (a *InodeAttrs) Stat(*vfs.Filesystem, vfs.StatOptions) (linux.Statx, error) } // SetStat implements Inode.SetStat. -func (a *InodeAttrs) SetStat(fs *vfs.Filesystem, creds *auth.Credentials, opts vfs.SetStatOptions) error { +func (a *InodeAttrs) SetStat(ctx context.Context, fs *vfs.Filesystem, creds *auth.Credentials, opts vfs.SetStatOptions) error { if opts.Stat.Mask == 0 { return nil } if opts.Stat.Mask&^(linux.STATX_MODE|linux.STATX_UID|linux.STATX_GID) != 0 { return syserror.EPERM } - if err := vfs.CheckSetStat(creds, &opts.Stat, uint16(a.Mode().Permissions()), auth.KUID(atomic.LoadUint32(&a.uid)), auth.KGID(atomic.LoadUint32(&a.gid))); err != nil { + if err := vfs.CheckSetStat(ctx, creds, &opts.Stat, uint16(a.Mode().Permissions()), auth.KUID(atomic.LoadUint32(&a.uid)), auth.KGID(atomic.LoadUint32(&a.gid))); err != nil { return err } @@ -566,7 +566,7 @@ func (s *StaticDirectory) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs } // SetStat implements Inode.SetStat not allowing inode attributes to be changed. -func (*StaticDirectory) SetStat(*vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error { +func (*StaticDirectory) SetStat(context.Context, *vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error { return syserror.EPERM } diff --git a/pkg/sentry/fsimpl/kernfs/kernfs.go b/pkg/sentry/fsimpl/kernfs/kernfs.go index b12b216d2..794e38908 100644 --- a/pkg/sentry/fsimpl/kernfs/kernfs.go +++ b/pkg/sentry/fsimpl/kernfs/kernfs.go @@ -333,7 +333,7 @@ type inodeMetadata interface { // vfs.FilesystemImpl.SetStatAt. Implementations are responsible for checking // if the operation can be performed (see vfs.CheckSetStat() for common // checks). - SetStat(fs *vfs.Filesystem, creds *auth.Credentials, opts vfs.SetStatOptions) error + SetStat(ctx context.Context, fs *vfs.Filesystem, creds *auth.Credentials, opts vfs.SetStatOptions) error } // Precondition: All methods in this interface may only be called on directory diff --git a/pkg/sentry/fsimpl/kernfs/kernfs_test.go b/pkg/sentry/fsimpl/kernfs/kernfs_test.go index 2875e6ffa..fb0d25ad7 100644 --- a/pkg/sentry/fsimpl/kernfs/kernfs_test.go +++ b/pkg/sentry/fsimpl/kernfs/kernfs_test.go @@ -91,7 +91,7 @@ type attrs struct { kernfs.InodeAttrs } -func (*attrs) SetStat(*vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error { +func (*attrs) SetStat(context.Context, *vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error { return syserror.EPERM } diff --git a/pkg/sentry/fsimpl/kernfs/symlink.go b/pkg/sentry/fsimpl/kernfs/symlink.go index 92f709d29..5918d3309 100644 --- a/pkg/sentry/fsimpl/kernfs/symlink.go +++ b/pkg/sentry/fsimpl/kernfs/symlink.go @@ -56,6 +56,6 @@ func (s *StaticSymlink) Readlink(_ context.Context) (string, error) { } // SetStat implements Inode.SetStat not allowing inode attributes to be changed. -func (*StaticSymlink) SetStat(*vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error { +func (*StaticSymlink) SetStat(context.Context, *vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error { return syserror.EPERM } diff --git a/pkg/sentry/fsimpl/proc/subtasks.go b/pkg/sentry/fsimpl/proc/subtasks.go index eb191aba4..a21313666 100644 --- a/pkg/sentry/fsimpl/proc/subtasks.go +++ b/pkg/sentry/fsimpl/proc/subtasks.go @@ -130,6 +130,6 @@ func (i *subtasksInode) Stat(vsfs *vfs.Filesystem, opts vfs.StatOptions) (linux. } // SetStat implements Inode.SetStat not allowing inode attributes to be changed. -func (*subtasksInode) SetStat(*vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error { +func (*subtasksInode) SetStat(context.Context, *vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error { return syserror.EPERM } diff --git a/pkg/sentry/fsimpl/proc/task.go b/pkg/sentry/fsimpl/proc/task.go index ceb427ffb..49d6efb0e 100644 --- a/pkg/sentry/fsimpl/proc/task.go +++ b/pkg/sentry/fsimpl/proc/task.go @@ -108,7 +108,7 @@ func (i *taskInode) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenO } // SetStat implements Inode.SetStat not allowing inode attributes to be changed. -func (*taskInode) SetStat(*vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error { +func (*taskInode) SetStat(context.Context, *vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error { return syserror.EPERM } diff --git a/pkg/sentry/fsimpl/proc/tasks_files.go b/pkg/sentry/fsimpl/proc/tasks_files.go index d3d99393f..882c1981e 100644 --- a/pkg/sentry/fsimpl/proc/tasks_files.go +++ b/pkg/sentry/fsimpl/proc/tasks_files.go @@ -64,7 +64,7 @@ func (s *selfSymlink) Readlink(ctx context.Context) (string, error) { } // SetStat implements Inode.SetStat not allowing inode attributes to be changed. -func (*selfSymlink) SetStat(*vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error { +func (*selfSymlink) SetStat(context.Context, *vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error { return syserror.EPERM } @@ -102,7 +102,7 @@ func (s *threadSelfSymlink) Readlink(ctx context.Context) (string, error) { } // SetStat implements Inode.SetStat not allowing inode attributes to be changed. -func (*threadSelfSymlink) SetStat(*vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error { +func (*threadSelfSymlink) SetStat(context.Context, *vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error { return syserror.EPERM } @@ -114,8 +114,8 @@ type dynamicBytesFileSetAttr struct { } // SetStat implements Inode.SetStat. -func (d *dynamicBytesFileSetAttr) SetStat(fs *vfs.Filesystem, creds *auth.Credentials, opts vfs.SetStatOptions) error { - return d.DynamicBytesFile.InodeAttrs.SetStat(fs, creds, opts) +func (d *dynamicBytesFileSetAttr) SetStat(ctx context.Context, fs *vfs.Filesystem, creds *auth.Credentials, opts vfs.SetStatOptions) error { + return d.DynamicBytesFile.InodeAttrs.SetStat(ctx, fs, creds, opts) } // cpuStats contains the breakdown of CPU time for /proc/stat. diff --git a/pkg/sentry/fsimpl/sys/sys.go b/pkg/sentry/fsimpl/sys/sys.go index 9c8e63783..7abfd62f2 100644 --- a/pkg/sentry/fsimpl/sys/sys.go +++ b/pkg/sentry/fsimpl/sys/sys.go @@ -95,7 +95,7 @@ func (fs *filesystem) newDir(creds *auth.Credentials, mode linux.FileMode, conte } // SetStat implements Inode.SetStat not allowing inode attributes to be changed. -func (*dir) SetStat(*vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error { +func (*dir) SetStat(context.Context, *vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error { return syserror.EPERM } diff --git a/pkg/sentry/fsimpl/tmpfs/filesystem.go b/pkg/sentry/fsimpl/tmpfs/filesystem.go index 6e8b4cae7..75d01b853 100644 --- a/pkg/sentry/fsimpl/tmpfs/filesystem.go +++ b/pkg/sentry/fsimpl/tmpfs/filesystem.go @@ -575,7 +575,7 @@ func (fs *filesystem) SetStatAt(ctx context.Context, rp *vfs.ResolvingPath, opts if err != nil { return err } - return d.inode.setStat(rp.Credentials(), &opts.Stat) + return d.inode.setStat(ctx, rp.Credentials(), &opts.Stat) } // StatAt implements vfs.FilesystemImpl.StatAt. diff --git a/pkg/sentry/fsimpl/tmpfs/regular_file.go b/pkg/sentry/fsimpl/tmpfs/regular_file.go index 711442424..5a2896bf6 100644 --- a/pkg/sentry/fsimpl/tmpfs/regular_file.go +++ b/pkg/sentry/fsimpl/tmpfs/regular_file.go @@ -308,11 +308,18 @@ func (fd *regularFileFD) PWrite(ctx context.Context, src usermem.IOSequence, off return 0, nil } f := fd.inode().impl.(*regularFile) - end := offset + srclen - if end < offset { + if end := offset + srclen; end < offset { // Overflow. return 0, syserror.EFBIG } + + var err error + srclen, err = vfs.CheckLimit(ctx, offset, srclen) + if err != nil { + return 0, err + } + src = src.TakeFirst64(srclen) + f.inode.mu.Lock() rw := getRegularFileReadWriter(f, offset) n, err := src.CopyInTo(ctx, rw) diff --git a/pkg/sentry/fsimpl/tmpfs/tmpfs.go b/pkg/sentry/fsimpl/tmpfs/tmpfs.go index c18f1e46e..ff69372b3 100644 --- a/pkg/sentry/fsimpl/tmpfs/tmpfs.go +++ b/pkg/sentry/fsimpl/tmpfs/tmpfs.go @@ -299,14 +299,14 @@ func (i *inode) statTo(stat *linux.Statx) { } } -func (i *inode) setStat(creds *auth.Credentials, stat *linux.Statx) error { +func (i *inode) setStat(ctx context.Context, creds *auth.Credentials, stat *linux.Statx) error { if stat.Mask == 0 { return nil } if stat.Mask&^(linux.STATX_MODE|linux.STATX_UID|linux.STATX_GID|linux.STATX_ATIME|linux.STATX_MTIME|linux.STATX_CTIME|linux.STATX_SIZE) != 0 { return syserror.EPERM } - if err := vfs.CheckSetStat(creds, stat, uint16(atomic.LoadUint32(&i.mode))&^linux.S_IFMT, auth.KUID(atomic.LoadUint32(&i.uid)), auth.KGID(atomic.LoadUint32(&i.gid))); err != nil { + if err := vfs.CheckSetStat(ctx, creds, stat, uint16(atomic.LoadUint32(&i.mode))&^linux.S_IFMT, auth.KUID(atomic.LoadUint32(&i.uid)), auth.KGID(atomic.LoadUint32(&i.gid))); err != nil { return err } i.mu.Lock() @@ -464,5 +464,5 @@ func (fd *fileDescription) Stat(ctx context.Context, opts vfs.StatOptions) (linu // SetStat implements vfs.FileDescriptionImpl.SetStat. func (fd *fileDescription) SetStat(ctx context.Context, opts vfs.SetStatOptions) error { creds := auth.CredentialsFromContext(ctx) - return fd.inode().setStat(creds, &opts.Stat) + return fd.inode().setStat(ctx, creds, &opts.Stat) } diff --git a/pkg/sentry/syscalls/linux/vfs2/setstat.go b/pkg/sentry/syscalls/linux/vfs2/setstat.go index 9250659ff..136453ccc 100644 --- a/pkg/sentry/syscalls/linux/vfs2/setstat.go +++ b/pkg/sentry/syscalls/linux/vfs2/setstat.go @@ -173,12 +173,13 @@ func Truncate(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysc return 0, nil, err } - return 0, nil, setstatat(t, linux.AT_FDCWD, path, disallowEmptyPath, followFinalSymlink, &vfs.SetStatOptions{ + err = setstatat(t, linux.AT_FDCWD, path, disallowEmptyPath, followFinalSymlink, &vfs.SetStatOptions{ Stat: linux.Statx{ Mask: linux.STATX_SIZE, Size: uint64(length), }, }) + return 0, nil, handleSetSizeError(t, err) } // Ftruncate implements Linux syscall ftruncate(2). @@ -196,12 +197,13 @@ func Ftruncate(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sys } defer file.DecRef() - return 0, nil, file.SetStat(t, vfs.SetStatOptions{ + err := file.SetStat(t, vfs.SetStatOptions{ Stat: linux.Statx{ Mask: linux.STATX_SIZE, Size: uint64(length), }, }) + return 0, nil, handleSetSizeError(t, err) } // Utime implements Linux syscall utime(2). @@ -378,3 +380,12 @@ func setstatat(t *kernel.Task, dirfd int32, path fspath.Path, shouldAllowEmptyPa FollowFinalSymlink: bool(shouldFollowFinalSymlink), }, opts) } + +func handleSetSizeError(t *kernel.Task, err error) error { + if err == syserror.ErrExceedsFileSizeLimit { + // Convert error to EFBIG and send a SIGXFSZ per setrlimit(2). + t.SendSignal(kernel.SignalInfoNoInfo(linux.SIGXFSZ, t, t)) + return syserror.EFBIG + } + return err +} diff --git a/pkg/sentry/vfs/BUILD b/pkg/sentry/vfs/BUILD index cb4deb068..a2a06fc8f 100644 --- a/pkg/sentry/vfs/BUILD +++ b/pkg/sentry/vfs/BUILD @@ -51,6 +51,7 @@ go_library( "//pkg/sentry/fs", "//pkg/sentry/fs/lock", "//pkg/sentry/kernel/auth", + "//pkg/sentry/limits", "//pkg/sentry/memmap", "//pkg/sync", "//pkg/syserror", diff --git a/pkg/sentry/vfs/file_description_impl_util.go b/pkg/sentry/vfs/file_description_impl_util.go index 45191d1c3..d45e602ce 100644 --- a/pkg/sentry/vfs/file_description_impl_util.go +++ b/pkg/sentry/vfs/file_description_impl_util.go @@ -339,6 +339,11 @@ func (fd *DynamicBytesFileDescriptionImpl) pwriteLocked(ctx context.Context, src if opts.Flags&^(linux.RWF_HIPRI|linux.RWF_DSYNC|linux.RWF_SYNC) != 0 { return 0, syserror.EOPNOTSUPP } + limit, err := CheckLimit(ctx, offset, src.NumBytes()) + if err != nil { + return 0, err + } + src = src.TakeFirst64(limit) writable, ok := fd.data.(WritableDynamicBytesSource) if !ok { diff --git a/pkg/sentry/vfs/permissions.go b/pkg/sentry/vfs/permissions.go index 8e250998a..2c8f23f55 100644 --- a/pkg/sentry/vfs/permissions.go +++ b/pkg/sentry/vfs/permissions.go @@ -15,8 +15,12 @@ package vfs import ( + "math" + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" + "gvisor.dev/gvisor/pkg/sentry/limits" "gvisor.dev/gvisor/pkg/syserror" ) @@ -147,7 +151,16 @@ func MayWriteFileWithOpenFlags(flags uint32) bool { // CheckSetStat checks that creds has permission to change the metadata of a // file with the given permissions, UID, and GID as specified by stat, subject // to the rules of Linux's fs/attr.c:setattr_prepare(). -func CheckSetStat(creds *auth.Credentials, stat *linux.Statx, mode uint16, kuid auth.KUID, kgid auth.KGID) error { +func CheckSetStat(ctx context.Context, creds *auth.Credentials, stat *linux.Statx, mode uint16, kuid auth.KUID, kgid auth.KGID) error { + if stat.Mask&linux.STATX_SIZE != 0 { + limit, err := CheckLimit(ctx, 0, int64(stat.Size)) + if err != nil { + return err + } + if limit < int64(stat.Size) { + return syserror.ErrExceedsFileSizeLimit + } + } if stat.Mask&linux.STATX_MODE != 0 { if !CanActAsOwner(creds, kuid) { return syserror.EPERM @@ -205,3 +218,21 @@ func CanActAsOwner(creds *auth.Credentials, kuid auth.KUID) bool { func HasCapabilityOnFile(creds *auth.Credentials, cp linux.Capability, kuid auth.KUID, kgid auth.KGID) bool { return creds.HasCapability(cp) && creds.UserNamespace.MapFromKUID(kuid).Ok() && creds.UserNamespace.MapFromKGID(kgid).Ok() } + +// CheckLimit enforces file size rlimits. It returns error if the write +// operation must not proceed. Otherwise it returns the max length allowed to +// without violating the limit. +func CheckLimit(ctx context.Context, offset, size int64) (int64, error) { + fileSizeLimit := limits.FromContext(ctx).Get(limits.FileSize).Cur + if fileSizeLimit > math.MaxInt64 { + return size, nil + } + if offset >= int64(fileSizeLimit) { + return 0, syserror.ErrExceedsFileSizeLimit + } + remaining := int64(fileSizeLimit) - offset + if remaining < size { + return remaining, nil + } + return size, nil +} -- cgit v1.2.3 From de694e5484502d53166d70b36141e62fcdf07803 Mon Sep 17 00:00:00 2001 From: Fabricio Voznika Date: Wed, 25 Mar 2020 19:12:25 -0700 Subject: Combine file mode and isDir arguments Updates #1035 PiperOrigin-RevId: 303021328 --- pkg/abi/linux/file.go | 5 +++++ pkg/sentry/fsimpl/ext/inode.go | 2 +- pkg/sentry/fsimpl/gofer/filesystem.go | 22 +++++++++++----------- pkg/sentry/fsimpl/gofer/gofer.go | 7 ++++--- pkg/sentry/fsimpl/host/host.go | 6 +++--- pkg/sentry/fsimpl/kernfs/fd_impl_util.go | 3 +-- pkg/sentry/fsimpl/kernfs/inode_impl_util.go | 6 ++---- pkg/sentry/fsimpl/proc/task.go | 9 +-------- pkg/sentry/fsimpl/tmpfs/filesystem.go | 24 ++++++++++++------------ pkg/sentry/fsimpl/tmpfs/tmpfs.go | 8 +++++--- pkg/sentry/vfs/anonfs.go | 2 +- pkg/sentry/vfs/permissions.go | 23 ++++++++++------------- 12 files changed, 56 insertions(+), 61 deletions(-) (limited to 'pkg/sentry/fsimpl/tmpfs/filesystem.go') diff --git a/pkg/abi/linux/file.go b/pkg/abi/linux/file.go index dbe58acbe..055ac1d7c 100644 --- a/pkg/abi/linux/file.go +++ b/pkg/abi/linux/file.go @@ -287,6 +287,11 @@ func (m FileMode) ExtraBits() FileMode { return m &^ (PermissionsMask | FileTypeMask) } +// IsDir returns true if file type represents a directory. +func (m FileMode) IsDir() bool { + return m.FileType() == S_IFDIR +} + // String returns a string representation of m. func (m FileMode) String() string { var s []string diff --git a/pkg/sentry/fsimpl/ext/inode.go b/pkg/sentry/fsimpl/ext/inode.go index 6962083f5..a39a37318 100644 --- a/pkg/sentry/fsimpl/ext/inode.go +++ b/pkg/sentry/fsimpl/ext/inode.go @@ -186,7 +186,7 @@ func (in *inode) open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts *vfs.OpenOpt } func (in *inode) checkPermissions(creds *auth.Credentials, ats vfs.AccessTypes) error { - return vfs.GenericCheckPermissions(creds, ats, in.isDir(), uint16(in.diskInode.Mode()), in.diskInode.UID(), in.diskInode.GID()) + return vfs.GenericCheckPermissions(creds, ats, in.diskInode.Mode(), in.diskInode.UID(), in.diskInode.GID()) } // statTo writes the statx fields to the output parameter. diff --git a/pkg/sentry/fsimpl/gofer/filesystem.go b/pkg/sentry/fsimpl/gofer/filesystem.go index 26b492185..1e43df9ec 100644 --- a/pkg/sentry/fsimpl/gofer/filesystem.go +++ b/pkg/sentry/fsimpl/gofer/filesystem.go @@ -119,7 +119,7 @@ func (fs *filesystem) stepLocked(ctx context.Context, rp *vfs.ResolvingPath, d * if !d.isDir() { return nil, syserror.ENOTDIR } - if err := d.checkPermissions(rp.Credentials(), vfs.MayExec, true); err != nil { + if err := d.checkPermissions(rp.Credentials(), vfs.MayExec); err != nil { return nil, err } afterSymlink: @@ -314,7 +314,7 @@ func (fs *filesystem) doCreateAt(ctx context.Context, rp *vfs.ResolvingPath, dir if err != nil { return err } - if err := parent.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec, true); err != nil { + if err := parent.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec); err != nil { return err } if parent.isDeleted() { @@ -378,7 +378,7 @@ func (fs *filesystem) unlinkAt(ctx context.Context, rp *vfs.ResolvingPath, dir b if err != nil { return err } - if err := parent.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec, true); err != nil { + if err := parent.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec); err != nil { return err } if err := rp.Mount().CheckBeginWrite(); err != nil { @@ -512,7 +512,7 @@ func (fs *filesystem) AccessAt(ctx context.Context, rp *vfs.ResolvingPath, creds if err != nil { return err } - return d.checkPermissions(creds, ats, d.isDir()) + return d.checkPermissions(creds, ats) } // GetDentryAt implements vfs.FilesystemImpl.GetDentryAt. @@ -528,7 +528,7 @@ func (fs *filesystem) GetDentryAt(ctx context.Context, rp *vfs.ResolvingPath, op if !d.isDir() { return nil, syserror.ENOTDIR } - if err := d.checkPermissions(rp.Credentials(), vfs.MayExec, true); err != nil { + if err := d.checkPermissions(rp.Credentials(), vfs.MayExec); err != nil { return nil, err } } @@ -624,7 +624,7 @@ afterTrailingSymlink: return nil, err } // Check for search permission in the parent directory. - if err := parent.checkPermissions(rp.Credentials(), vfs.MayExec, true); err != nil { + if err := parent.checkPermissions(rp.Credentials(), vfs.MayExec); err != nil { return nil, err } // Determine whether or not we need to create a file. @@ -661,7 +661,7 @@ afterTrailingSymlink: // Preconditions: fs.renameMu must be locked. func (d *dentry) openLocked(ctx context.Context, rp *vfs.ResolvingPath, opts *vfs.OpenOptions) (*vfs.FileDescription, error) { ats := vfs.AccessTypesForOpenFlags(opts) - if err := d.checkPermissions(rp.Credentials(), ats, d.isDir()); err != nil { + if err := d.checkPermissions(rp.Credentials(), ats); err != nil { return nil, err } mnt := rp.Mount() @@ -722,7 +722,7 @@ func (d *dentry) openLocked(ctx context.Context, rp *vfs.ResolvingPath, opts *vf // Preconditions: d.fs.renameMu must be locked. d.dirMu must be locked. func (d *dentry) createAndOpenChildLocked(ctx context.Context, rp *vfs.ResolvingPath, opts *vfs.OpenOptions) (*vfs.FileDescription, error) { - if err := d.checkPermissions(rp.Credentials(), vfs.MayWrite, true); err != nil { + if err := d.checkPermissions(rp.Credentials(), vfs.MayWrite); err != nil { return nil, err } if d.isDeleted() { @@ -884,7 +884,7 @@ func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa return err } } - if err := oldParent.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec, true); err != nil { + if err := oldParent.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec); err != nil { return err } vfsObj := rp.VirtualFilesystem() @@ -904,7 +904,7 @@ func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa return syserror.EINVAL } if oldParent != newParent { - if err := renamed.checkPermissions(rp.Credentials(), vfs.MayWrite, true); err != nil { + if err := renamed.checkPermissions(rp.Credentials(), vfs.MayWrite); err != nil { return err } } @@ -915,7 +915,7 @@ func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa } if oldParent != newParent { - if err := newParent.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec, true); err != nil { + if err := newParent.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec); err != nil { return err } newParent.dirMu.Lock() diff --git a/pkg/sentry/fsimpl/gofer/gofer.go b/pkg/sentry/fsimpl/gofer/gofer.go index 13928ce36..cf276a417 100644 --- a/pkg/sentry/fsimpl/gofer/gofer.go +++ b/pkg/sentry/fsimpl/gofer/gofer.go @@ -721,7 +721,8 @@ func (d *dentry) setStat(ctx context.Context, creds *auth.Credentials, stat *lin if stat.Mask&^(linux.STATX_MODE|linux.STATX_UID|linux.STATX_GID|linux.STATX_ATIME|linux.STATX_MTIME|linux.STATX_SIZE) != 0 { return syserror.EPERM } - if err := vfs.CheckSetStat(ctx, creds, stat, uint16(atomic.LoadUint32(&d.mode))&^linux.S_IFMT, auth.KUID(atomic.LoadUint32(&d.uid)), auth.KGID(atomic.LoadUint32(&d.gid))); err != nil { + mode := linux.FileMode(atomic.LoadUint32(&d.mode)) + if err := vfs.CheckSetStat(ctx, creds, stat, mode, auth.KUID(atomic.LoadUint32(&d.uid)), auth.KGID(atomic.LoadUint32(&d.gid))); err != nil { return err } if err := mnt.CheckBeginWrite(); err != nil { @@ -843,8 +844,8 @@ func (d *dentry) setStat(ctx context.Context, creds *auth.Credentials, stat *lin return nil } -func (d *dentry) checkPermissions(creds *auth.Credentials, ats vfs.AccessTypes, isDir bool) error { - return vfs.GenericCheckPermissions(creds, ats, isDir, uint16(atomic.LoadUint32(&d.mode))&0777, auth.KUID(atomic.LoadUint32(&d.uid)), auth.KGID(atomic.LoadUint32(&d.gid))) +func (d *dentry) checkPermissions(creds *auth.Credentials, ats vfs.AccessTypes) error { + return vfs.GenericCheckPermissions(creds, ats, linux.FileMode(atomic.LoadUint32(&d.mode)), auth.KUID(atomic.LoadUint32(&d.uid)), auth.KGID(atomic.LoadUint32(&d.gid))) } // IncRef implements vfs.DentryImpl.IncRef. diff --git a/pkg/sentry/fsimpl/host/host.go b/pkg/sentry/fsimpl/host/host.go index 1f735628f..a54985ef5 100644 --- a/pkg/sentry/fsimpl/host/host.go +++ b/pkg/sentry/fsimpl/host/host.go @@ -167,8 +167,8 @@ func fileFlagsFromHostFD(fd int) (int, error) { } // CheckPermissions implements kernfs.Inode. -func (i *inode) CheckPermissions(ctx context.Context, creds *auth.Credentials, atx vfs.AccessTypes) error { - return vfs.GenericCheckPermissions(creds, atx, false /* isDir */, uint16(i.mode), i.uid, i.gid) +func (i *inode) CheckPermissions(ctx context.Context, creds *auth.Credentials, ats vfs.AccessTypes) error { + return vfs.GenericCheckPermissions(creds, ats, i.mode, i.uid, i.gid) } // Mode implements kernfs.Inode. @@ -306,7 +306,7 @@ func (i *inode) SetStat(ctx context.Context, fs *vfs.Filesystem, creds *auth.Cre if m&^(linux.STATX_MODE|linux.STATX_SIZE|linux.STATX_ATIME|linux.STATX_MTIME) != 0 { return syserror.EPERM } - if err := vfs.CheckSetStat(ctx, creds, &s, uint16(i.Mode().Permissions()), i.uid, i.gid); err != nil { + if err := vfs.CheckSetStat(ctx, creds, &s, i.Mode(), i.uid, i.gid); err != nil { return err } diff --git a/pkg/sentry/fsimpl/kernfs/fd_impl_util.go b/pkg/sentry/fsimpl/kernfs/fd_impl_util.go index 75c4bab1a..bfa786c88 100644 --- a/pkg/sentry/fsimpl/kernfs/fd_impl_util.go +++ b/pkg/sentry/fsimpl/kernfs/fd_impl_util.go @@ -206,8 +206,7 @@ func (fd *GenericDirectoryFD) Stat(ctx context.Context, opts vfs.StatOptions) (l // SetStat implements vfs.FileDescriptionImpl.SetStat. func (fd *GenericDirectoryFD) SetStat(ctx context.Context, opts vfs.SetStatOptions) error { - fs := fd.filesystem() creds := auth.CredentialsFromContext(ctx) inode := fd.vfsfd.VirtualDentry().Dentry().Impl().(*Dentry).inode - return inode.SetStat(ctx, fs, creds, opts) + return inode.SetStat(ctx, fd.filesystem(), creds, opts) } diff --git a/pkg/sentry/fsimpl/kernfs/inode_impl_util.go b/pkg/sentry/fsimpl/kernfs/inode_impl_util.go index c612dcf07..5c84b10c9 100644 --- a/pkg/sentry/fsimpl/kernfs/inode_impl_util.go +++ b/pkg/sentry/fsimpl/kernfs/inode_impl_util.go @@ -241,7 +241,7 @@ func (a *InodeAttrs) SetStat(ctx context.Context, fs *vfs.Filesystem, creds *aut if opts.Stat.Mask&^(linux.STATX_MODE|linux.STATX_UID|linux.STATX_GID) != 0 { return syserror.EPERM } - if err := vfs.CheckSetStat(ctx, creds, &opts.Stat, uint16(a.Mode().Permissions()), auth.KUID(atomic.LoadUint32(&a.uid)), auth.KGID(atomic.LoadUint32(&a.gid))); err != nil { + if err := vfs.CheckSetStat(ctx, creds, &opts.Stat, a.Mode(), auth.KUID(atomic.LoadUint32(&a.uid)), auth.KGID(atomic.LoadUint32(&a.gid))); err != nil { return err } @@ -273,12 +273,10 @@ func (a *InodeAttrs) SetStat(ctx context.Context, fs *vfs.Filesystem, creds *aut // CheckPermissions implements Inode.CheckPermissions. func (a *InodeAttrs) CheckPermissions(_ context.Context, creds *auth.Credentials, ats vfs.AccessTypes) error { - mode := a.Mode() return vfs.GenericCheckPermissions( creds, ats, - mode.FileType() == linux.ModeDirectory, - uint16(mode), + a.Mode(), auth.KUID(atomic.LoadUint32(&a.uid)), auth.KGID(atomic.LoadUint32(&a.gid)), ) diff --git a/pkg/sentry/fsimpl/proc/task.go b/pkg/sentry/fsimpl/proc/task.go index 49d6efb0e..aee2a4392 100644 --- a/pkg/sentry/fsimpl/proc/task.go +++ b/pkg/sentry/fsimpl/proc/task.go @@ -172,14 +172,7 @@ func (i *taskOwnedInode) Stat(fs *vfs.Filesystem, opts vfs.StatOptions) (linux.S func (i *taskOwnedInode) CheckPermissions(_ context.Context, creds *auth.Credentials, ats vfs.AccessTypes) error { mode := i.Mode() uid, gid := i.getOwner(mode) - return vfs.GenericCheckPermissions( - creds, - ats, - mode.FileType() == linux.ModeDirectory, - uint16(mode), - uid, - gid, - ) + return vfs.GenericCheckPermissions(creds, ats, mode, uid, gid) } func (i *taskOwnedInode) getOwner(mode linux.FileMode) (auth.KUID, auth.KGID) { diff --git a/pkg/sentry/fsimpl/tmpfs/filesystem.go b/pkg/sentry/fsimpl/tmpfs/filesystem.go index 75d01b853..12cc64385 100644 --- a/pkg/sentry/fsimpl/tmpfs/filesystem.go +++ b/pkg/sentry/fsimpl/tmpfs/filesystem.go @@ -41,7 +41,7 @@ func stepLocked(rp *vfs.ResolvingPath, d *dentry) (*dentry, error) { if !d.inode.isDir() { return nil, syserror.ENOTDIR } - if err := d.inode.checkPermissions(rp.Credentials(), vfs.MayExec, true); err != nil { + if err := d.inode.checkPermissions(rp.Credentials(), vfs.MayExec); err != nil { return nil, err } afterSymlink: @@ -125,7 +125,7 @@ func (fs *filesystem) doCreateAt(rp *vfs.ResolvingPath, dir bool, create func(pa if err != nil { return err } - if err := parent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec, true /* isDir */); err != nil { + if err := parent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec); err != nil { return err } name := rp.Component() @@ -163,7 +163,7 @@ func (fs *filesystem) AccessAt(ctx context.Context, rp *vfs.ResolvingPath, creds if err != nil { return err } - return d.inode.checkPermissions(creds, ats, d.inode.isDir()) + return d.inode.checkPermissions(creds, ats) } // GetDentryAt implements vfs.FilesystemImpl.GetDentryAt. @@ -178,7 +178,7 @@ func (fs *filesystem) GetDentryAt(ctx context.Context, rp *vfs.ResolvingPath, op if !d.inode.isDir() { return nil, syserror.ENOTDIR } - if err := d.inode.checkPermissions(rp.Credentials(), vfs.MayExec, true /* isDir */); err != nil { + if err := d.inode.checkPermissions(rp.Credentials(), vfs.MayExec); err != nil { return nil, err } } @@ -301,7 +301,7 @@ afterTrailingSymlink: return nil, err } // Check for search permission in the parent directory. - if err := parent.inode.checkPermissions(rp.Credentials(), vfs.MayExec, true); err != nil { + if err := parent.inode.checkPermissions(rp.Credentials(), vfs.MayExec); err != nil { return nil, err } // Reject attempts to open directories with O_CREAT. @@ -316,7 +316,7 @@ afterTrailingSymlink: child, err := stepLocked(rp, parent) if err == syserror.ENOENT { // Already checked for searchability above; now check for writability. - if err := parent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite, true); err != nil { + if err := parent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite); err != nil { return nil, err } if err := rp.Mount().CheckBeginWrite(); err != nil { @@ -347,7 +347,7 @@ afterTrailingSymlink: func (d *dentry) open(ctx context.Context, rp *vfs.ResolvingPath, opts *vfs.OpenOptions, afterCreate bool) (*vfs.FileDescription, error) { ats := vfs.AccessTypesForOpenFlags(opts) if !afterCreate { - if err := d.inode.checkPermissions(rp.Credentials(), ats, d.inode.isDir()); err != nil { + if err := d.inode.checkPermissions(rp.Credentials(), ats); err != nil { return nil, err } } @@ -428,7 +428,7 @@ func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa defer mnt.EndWrite() oldParent := oldParentVD.Dentry().Impl().(*dentry) - if err := oldParent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec, true /* isDir */); err != nil { + if err := oldParent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec); err != nil { return err } // Call vfs.Dentry.Child() instead of stepLocked() or rp.ResolveChild(), @@ -445,7 +445,7 @@ func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa } if oldParent != newParent { // Writability is needed to change renamed's "..". - if err := renamed.inode.checkPermissions(rp.Credentials(), vfs.MayWrite, true /* isDir */); err != nil { + if err := renamed.inode.checkPermissions(rp.Credentials(), vfs.MayWrite); err != nil { return err } } @@ -455,7 +455,7 @@ func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa } } - if err := newParent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec, true /* isDir */); err != nil { + if err := newParent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec); err != nil { return err } replacedVFSD := newParent.vfsd.Child(newName) @@ -528,7 +528,7 @@ func (fs *filesystem) RmdirAt(ctx context.Context, rp *vfs.ResolvingPath) error if err != nil { return err } - if err := parent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec, true /* isDir */); err != nil { + if err := parent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec); err != nil { return err } name := rp.Component() @@ -621,7 +621,7 @@ func (fs *filesystem) UnlinkAt(ctx context.Context, rp *vfs.ResolvingPath) error if err != nil { return err } - if err := parent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec, true /* isDir */); err != nil { + if err := parent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec); err != nil { return err } name := rp.Component() diff --git a/pkg/sentry/fsimpl/tmpfs/tmpfs.go b/pkg/sentry/fsimpl/tmpfs/tmpfs.go index 2d5070a46..2f9e6c876 100644 --- a/pkg/sentry/fsimpl/tmpfs/tmpfs.go +++ b/pkg/sentry/fsimpl/tmpfs/tmpfs.go @@ -245,8 +245,9 @@ func (i *inode) decRef() { } } -func (i *inode) checkPermissions(creds *auth.Credentials, ats vfs.AccessTypes, isDir bool) error { - return vfs.GenericCheckPermissions(creds, ats, isDir, uint16(atomic.LoadUint32(&i.mode)), auth.KUID(atomic.LoadUint32(&i.uid)), auth.KGID(atomic.LoadUint32(&i.gid))) +func (i *inode) checkPermissions(creds *auth.Credentials, ats vfs.AccessTypes) error { + mode := linux.FileMode(atomic.LoadUint32(&i.mode)) + return vfs.GenericCheckPermissions(creds, ats, mode, auth.KUID(atomic.LoadUint32(&i.uid)), auth.KGID(atomic.LoadUint32(&i.gid))) } // Go won't inline this function, and returning linux.Statx (which is quite @@ -299,7 +300,8 @@ func (i *inode) setStat(ctx context.Context, creds *auth.Credentials, stat *linu if stat.Mask&^(linux.STATX_MODE|linux.STATX_UID|linux.STATX_GID|linux.STATX_ATIME|linux.STATX_MTIME|linux.STATX_CTIME|linux.STATX_SIZE) != 0 { return syserror.EPERM } - if err := vfs.CheckSetStat(ctx, creds, stat, uint16(atomic.LoadUint32(&i.mode))&^linux.S_IFMT, auth.KUID(atomic.LoadUint32(&i.uid)), auth.KGID(atomic.LoadUint32(&i.gid))); err != nil { + mode := linux.FileMode(atomic.LoadUint32(&i.mode)) + if err := vfs.CheckSetStat(ctx, creds, stat, mode, auth.KUID(atomic.LoadUint32(&i.uid)), auth.KGID(atomic.LoadUint32(&i.gid))); err != nil { return err } i.mu.Lock() diff --git a/pkg/sentry/vfs/anonfs.go b/pkg/sentry/vfs/anonfs.go index 925996517..a62e43589 100644 --- a/pkg/sentry/vfs/anonfs.go +++ b/pkg/sentry/vfs/anonfs.go @@ -83,7 +83,7 @@ func (fs *anonFilesystem) AccessAt(ctx context.Context, rp *ResolvingPath, creds if !rp.Done() { return syserror.ENOTDIR } - return GenericCheckPermissions(creds, ats, false /* isDir */, anonFileMode, anonFileUID, anonFileGID) + return GenericCheckPermissions(creds, ats, anonFileMode, anonFileUID, anonFileGID) } // GetDentryAt implements FilesystemImpl.GetDentryAt. diff --git a/pkg/sentry/vfs/permissions.go b/pkg/sentry/vfs/permissions.go index 2c8f23f55..f9647f90e 100644 --- a/pkg/sentry/vfs/permissions.go +++ b/pkg/sentry/vfs/permissions.go @@ -29,9 +29,9 @@ type AccessTypes uint16 // Bits in AccessTypes. const ( + MayExec AccessTypes = 1 + MayWrite AccessTypes = 2 MayRead AccessTypes = 4 - MayWrite = 2 - MayExec = 1 ) // OnlyRead returns true if access _only_ allows read. @@ -56,16 +56,17 @@ func (a AccessTypes) MayExec() bool { // GenericCheckPermissions checks that creds has the given access rights on a // file with the given permissions, UID, and GID, subject to the rules of -// fs/namei.c:generic_permission(). isDir is true if the file is a directory. -func GenericCheckPermissions(creds *auth.Credentials, ats AccessTypes, isDir bool, mode uint16, kuid auth.KUID, kgid auth.KGID) error { +// fs/namei.c:generic_permission(). +func GenericCheckPermissions(creds *auth.Credentials, ats AccessTypes, mode linux.FileMode, kuid auth.KUID, kgid auth.KGID) error { // Check permission bits. - perms := mode + perms := uint16(mode.Permissions()) if creds.EffectiveKUID == kuid { perms >>= 6 } else if creds.InGroup(kgid) { perms >>= 3 } if uint16(ats)&perms == uint16(ats) { + // All permission bits match, access granted. return nil } @@ -77,7 +78,7 @@ func GenericCheckPermissions(creds *auth.Credentials, ats AccessTypes, isDir boo } // CAP_DAC_READ_SEARCH allows the caller to read and search arbitrary // directories, and read arbitrary non-directory files. - if (isDir && !ats.MayWrite()) || ats.OnlyRead() { + if (mode.IsDir() && !ats.MayWrite()) || ats.OnlyRead() { if creds.HasCapability(linux.CAP_DAC_READ_SEARCH) { return nil } @@ -85,7 +86,7 @@ func GenericCheckPermissions(creds *auth.Credentials, ats AccessTypes, isDir boo // CAP_DAC_OVERRIDE allows arbitrary access to directories, read/write // access to non-directory files, and execute access to non-directory files // for which at least one execute bit is set. - if isDir || !ats.MayExec() || (mode&0111 != 0) { + if mode.IsDir() || !ats.MayExec() || (mode.Permissions()&0111 != 0) { if creds.HasCapability(linux.CAP_DAC_OVERRIDE) { return nil } @@ -151,7 +152,7 @@ func MayWriteFileWithOpenFlags(flags uint32) bool { // CheckSetStat checks that creds has permission to change the metadata of a // file with the given permissions, UID, and GID as specified by stat, subject // to the rules of Linux's fs/attr.c:setattr_prepare(). -func CheckSetStat(ctx context.Context, creds *auth.Credentials, stat *linux.Statx, mode uint16, kuid auth.KUID, kgid auth.KGID) error { +func CheckSetStat(ctx context.Context, creds *auth.Credentials, stat *linux.Statx, mode linux.FileMode, kuid auth.KUID, kgid auth.KGID) error { if stat.Mask&linux.STATX_SIZE != 0 { limit, err := CheckLimit(ctx, 0, int64(stat.Size)) if err != nil { @@ -190,11 +191,7 @@ func CheckSetStat(ctx context.Context, creds *auth.Credentials, stat *linux.Stat (stat.Mask&linux.STATX_CTIME != 0 && stat.Ctime.Nsec != linux.UTIME_NOW) { return syserror.EPERM } - // isDir is irrelevant in the following call to - // GenericCheckPermissions since ats == MayWrite means that - // CAP_DAC_READ_SEARCH does not apply, and CAP_DAC_OVERRIDE - // applies, regardless of isDir. - if err := GenericCheckPermissions(creds, MayWrite, false /* isDir */, mode, kuid, kgid); err != nil { + if err := GenericCheckPermissions(creds, MayWrite, mode, kuid, kgid); err != nil { return err } } -- cgit v1.2.3 From 76a7ace751bfd4b16411edbc0a2b06d0308b8832 Mon Sep 17 00:00:00 2001 From: Dean Deng Date: Thu, 26 Mar 2020 21:47:46 -0700 Subject: Add BoundEndpointAt filesystem operation. BoundEndpointAt() is needed to support Unix sockets bound at a file path, corresponding to BoundEndpoint() in VFS1. Updates #1476. PiperOrigin-RevId: 303258251 --- pkg/sentry/fsimpl/ext/BUILD | 1 + pkg/sentry/fsimpl/ext/filesystem.go | 12 ++++++++++ pkg/sentry/fsimpl/gofer/BUILD | 1 + pkg/sentry/fsimpl/gofer/filesystem.go | 8 +++++++ pkg/sentry/fsimpl/kernfs/BUILD | 1 + pkg/sentry/fsimpl/kernfs/filesystem.go | 13 ++++++++++ pkg/sentry/fsimpl/tmpfs/BUILD | 1 + pkg/sentry/fsimpl/tmpfs/filesystem.go | 8 +++++++ pkg/sentry/vfs/BUILD | 1 + pkg/sentry/vfs/anonfs.go | 9 +++++++ pkg/sentry/vfs/filesystem.go | 8 ++++++- pkg/sentry/vfs/vfs.go | 44 +++++++++++++++++++++++++++------- pkg/syserror/syserror.go | 1 + 13 files changed, 99 insertions(+), 9 deletions(-) (limited to 'pkg/sentry/fsimpl/tmpfs/filesystem.go') diff --git a/pkg/sentry/fsimpl/ext/BUILD b/pkg/sentry/fsimpl/ext/BUILD index 6f78f478f..d83d75b3d 100644 --- a/pkg/sentry/fsimpl/ext/BUILD +++ b/pkg/sentry/fsimpl/ext/BUILD @@ -45,6 +45,7 @@ go_library( "//pkg/sentry/fsimpl/ext/disklayout", "//pkg/sentry/kernel/auth", "//pkg/sentry/memmap", + "//pkg/sentry/socket/unix/transport", "//pkg/sentry/syscalls/linux", "//pkg/sentry/vfs", "//pkg/sync", diff --git a/pkg/sentry/fsimpl/ext/filesystem.go b/pkg/sentry/fsimpl/ext/filesystem.go index 8497be615..48eaccdbc 100644 --- a/pkg/sentry/fsimpl/ext/filesystem.go +++ b/pkg/sentry/fsimpl/ext/filesystem.go @@ -23,6 +23,7 @@ import ( "gvisor.dev/gvisor/pkg/fspath" "gvisor.dev/gvisor/pkg/sentry/fsimpl/ext/disklayout" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" + "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" @@ -463,6 +464,17 @@ func (fs *filesystem) UnlinkAt(ctx context.Context, rp *vfs.ResolvingPath) error return syserror.EROFS } +// BoundEndpointAt implements FilesystemImpl.BoundEndpointAt. +func (fs *filesystem) BoundEndpointAt(ctx context.Context, rp *vfs.ResolvingPath) (transport.BoundEndpoint, error) { + _, _, err := fs.walk(rp, false) + if err != nil { + return nil, err + } + + // TODO(b/134676337): Support sockets. + return nil, syserror.ECONNREFUSED +} + // ListxattrAt implements vfs.FilesystemImpl.ListxattrAt. func (fs *filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath) ([]string, error) { _, _, err := fs.walk(rp, false) diff --git a/pkg/sentry/fsimpl/gofer/BUILD b/pkg/sentry/fsimpl/gofer/BUILD index 4ba76a1e8..d15a36709 100644 --- a/pkg/sentry/fsimpl/gofer/BUILD +++ b/pkg/sentry/fsimpl/gofer/BUILD @@ -46,6 +46,7 @@ go_library( "//pkg/sentry/memmap", "//pkg/sentry/pgalloc", "//pkg/sentry/platform", + "//pkg/sentry/socket/unix/transport", "//pkg/sentry/usage", "//pkg/sentry/vfs", "//pkg/syserror", diff --git a/pkg/sentry/fsimpl/gofer/filesystem.go b/pkg/sentry/fsimpl/gofer/filesystem.go index 1e43df9ec..269624362 100644 --- a/pkg/sentry/fsimpl/gofer/filesystem.go +++ b/pkg/sentry/fsimpl/gofer/filesystem.go @@ -22,6 +22,7 @@ import ( "gvisor.dev/gvisor/pkg/fspath" "gvisor.dev/gvisor/pkg/p9" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" + "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/syserror" ) @@ -1059,6 +1060,13 @@ func (fs *filesystem) UnlinkAt(ctx context.Context, rp *vfs.ResolvingPath) error return fs.unlinkAt(ctx, rp, false /* dir */) } +// BoundEndpointAt implements FilesystemImpl.BoundEndpointAt. +// +// TODO(gvisor.dev/issue/1476): Implement BoundEndpointAt. +func (fs *filesystem) BoundEndpointAt(ctx context.Context, rp *vfs.ResolvingPath) (transport.BoundEndpoint, error) { + return nil, syserror.ECONNREFUSED +} + // ListxattrAt implements vfs.FilesystemImpl.ListxattrAt. func (fs *filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath) ([]string, error) { var ds *[]*dentry diff --git a/pkg/sentry/fsimpl/kernfs/BUILD b/pkg/sentry/fsimpl/kernfs/BUILD index e73f1f857..b3d6299d0 100644 --- a/pkg/sentry/fsimpl/kernfs/BUILD +++ b/pkg/sentry/fsimpl/kernfs/BUILD @@ -35,6 +35,7 @@ go_library( "//pkg/refs", "//pkg/sentry/kernel/auth", "//pkg/sentry/memmap", + "//pkg/sentry/socket/unix/transport", "//pkg/sentry/vfs", "//pkg/sync", "//pkg/syserror", diff --git a/pkg/sentry/fsimpl/kernfs/filesystem.go b/pkg/sentry/fsimpl/kernfs/filesystem.go index 31da8b511..a429fa23d 100644 --- a/pkg/sentry/fsimpl/kernfs/filesystem.go +++ b/pkg/sentry/fsimpl/kernfs/filesystem.go @@ -23,6 +23,7 @@ import ( "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fspath" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" + "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/syserror" ) @@ -728,6 +729,18 @@ func (fs *Filesystem) UnlinkAt(ctx context.Context, rp *vfs.ResolvingPath) error return nil } +// BoundEndpointAt implements FilesystemImpl.BoundEndpointAt. +func (fs *Filesystem) BoundEndpointAt(ctx context.Context, rp *vfs.ResolvingPath) (transport.BoundEndpoint, error) { + fs.mu.RLock() + _, _, err := fs.walkExistingLocked(ctx, rp) + fs.mu.RUnlock() + fs.processDeferredDecRefs() + if err != nil { + return nil, err + } + return nil, syserror.ECONNREFUSED +} + // ListxattrAt implements vfs.FilesystemImpl.ListxattrAt. func (fs *Filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath) ([]string, error) { fs.mu.RLock() diff --git a/pkg/sentry/fsimpl/tmpfs/BUILD b/pkg/sentry/fsimpl/tmpfs/BUILD index 57abd5583..6ea35affb 100644 --- a/pkg/sentry/fsimpl/tmpfs/BUILD +++ b/pkg/sentry/fsimpl/tmpfs/BUILD @@ -46,6 +46,7 @@ go_library( "//pkg/sentry/memmap", "//pkg/sentry/pgalloc", "//pkg/sentry/platform", + "//pkg/sentry/socket/unix/transport", "//pkg/sentry/usage", "//pkg/sentry/vfs", "//pkg/sentry/vfs/lock", diff --git a/pkg/sentry/fsimpl/tmpfs/filesystem.go b/pkg/sentry/fsimpl/tmpfs/filesystem.go index 12cc64385..e678ecc37 100644 --- a/pkg/sentry/fsimpl/tmpfs/filesystem.go +++ b/pkg/sentry/fsimpl/tmpfs/filesystem.go @@ -21,6 +21,7 @@ import ( "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fspath" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" + "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/syserror" ) @@ -656,6 +657,13 @@ func (fs *filesystem) UnlinkAt(ctx context.Context, rp *vfs.ResolvingPath) error return nil } +// BoundEndpointAt implements FilesystemImpl.BoundEndpointAt. +// +// TODO(gvisor.dev/issue/1476): Implement BoundEndpointAt. +func (fs *filesystem) BoundEndpointAt(ctx context.Context, rp *vfs.ResolvingPath) (transport.BoundEndpoint, error) { + return nil, syserror.ECONNREFUSED +} + // ListxattrAt implements vfs.FilesystemImpl.ListxattrAt. func (fs *filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath) ([]string, error) { fs.mu.RLock() diff --git a/pkg/sentry/vfs/BUILD b/pkg/sentry/vfs/BUILD index a2a06fc8f..bf4d27c7d 100644 --- a/pkg/sentry/vfs/BUILD +++ b/pkg/sentry/vfs/BUILD @@ -53,6 +53,7 @@ go_library( "//pkg/sentry/kernel/auth", "//pkg/sentry/limits", "//pkg/sentry/memmap", + "//pkg/sentry/socket/unix/transport", "//pkg/sync", "//pkg/syserror", "//pkg/usermem", diff --git a/pkg/sentry/vfs/anonfs.go b/pkg/sentry/vfs/anonfs.go index a62e43589..f58867066 100644 --- a/pkg/sentry/vfs/anonfs.go +++ b/pkg/sentry/vfs/anonfs.go @@ -21,6 +21,7 @@ import ( "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fspath" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" + "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/usermem" ) @@ -222,6 +223,14 @@ func (fs *anonFilesystem) UnlinkAt(ctx context.Context, rp *ResolvingPath) error return syserror.EPERM } +// BoundEndpointAt implements FilesystemImpl.BoundEndpointAt. +func (fs *anonFilesystem) BoundEndpointAt(ctx context.Context, rp *ResolvingPath) (transport.BoundEndpoint, error) { + if !rp.Final() { + return nil, syserror.ENOTDIR + } + return nil, syserror.ECONNREFUSED +} + // ListxattrAt implements FilesystemImpl.ListxattrAt. func (fs *anonFilesystem) ListxattrAt(ctx context.Context, rp *ResolvingPath) ([]string, error) { if !rp.Done() { diff --git a/pkg/sentry/vfs/filesystem.go b/pkg/sentry/vfs/filesystem.go index 332decce6..7b7d233f9 100644 --- a/pkg/sentry/vfs/filesystem.go +++ b/pkg/sentry/vfs/filesystem.go @@ -21,6 +21,7 @@ import ( "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fspath" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" + "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" ) // A Filesystem is a tree of nodes represented by Dentries, which forms part of @@ -460,6 +461,11 @@ type FilesystemImpl interface { // RemovexattrAt returns ENOTSUP. RemovexattrAt(ctx context.Context, rp *ResolvingPath, name string) error + // BoundEndpointAt returns the Unix socket endpoint bound at the path rp. + // + // - If a non-socket file exists at rp, then BoundEndpointAt returns ECONNREFUSED. + BoundEndpointAt(ctx context.Context, rp *ResolvingPath) (transport.BoundEndpoint, error) + // PrependPath prepends a path from vd to vd.Mount().Root() to b. // // If vfsroot.Ok(), it is the contextual VFS root; if it is encountered @@ -482,7 +488,7 @@ type FilesystemImpl interface { // Preconditions: vd.Mount().Filesystem().Impl() == this FilesystemImpl. PrependPath(ctx context.Context, vfsroot, vd VirtualDentry, b *fspath.Builder) error - // TODO: inotify_add_watch(); bind() + // TODO: inotify_add_watch() } // PrependPathAtVFSRootError is returned by implementations of diff --git a/pkg/sentry/vfs/vfs.go b/pkg/sentry/vfs/vfs.go index 03d1fb943..1708c1a53 100644 --- a/pkg/sentry/vfs/vfs.go +++ b/pkg/sentry/vfs/vfs.go @@ -38,6 +38,7 @@ import ( "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/fspath" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" + "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" ) @@ -230,7 +231,7 @@ func (vfs *VirtualFilesystem) getParentDirAndName(ctx context.Context, creds *au } if checkInvariants { if rp.canHandleError(err) && rp.Done() { - panic(fmt.Sprintf("%T.GetParentDentryAt() consumed all path components and returned %T", rp.mount.fs.impl, err)) + panic(fmt.Sprintf("%T.GetParentDentryAt() consumed all path components and returned %v", rp.mount.fs.impl, err)) } } if !rp.handleError(err) { @@ -271,7 +272,7 @@ func (vfs *VirtualFilesystem) LinkAt(ctx context.Context, creds *auth.Credential } if checkInvariants { if rp.canHandleError(err) && rp.Done() { - panic(fmt.Sprintf("%T.LinkAt() consumed all path components and returned %T", rp.mount.fs.impl, err)) + panic(fmt.Sprintf("%T.LinkAt() consumed all path components and returned %v", rp.mount.fs.impl, err)) } } if !rp.handleError(err) { @@ -307,7 +308,7 @@ func (vfs *VirtualFilesystem) MkdirAt(ctx context.Context, creds *auth.Credentia } if checkInvariants { if rp.canHandleError(err) && rp.Done() { - panic(fmt.Sprintf("%T.MkdirAt() consumed all path components and returned %T", rp.mount.fs.impl, err)) + panic(fmt.Sprintf("%T.MkdirAt() consumed all path components and returned %v", rp.mount.fs.impl, err)) } } if !rp.handleError(err) { @@ -340,7 +341,7 @@ func (vfs *VirtualFilesystem) MknodAt(ctx context.Context, creds *auth.Credentia } if checkInvariants { if rp.canHandleError(err) && rp.Done() { - panic(fmt.Sprintf("%T.MknodAt() consumed all path components and returned %T", rp.mount.fs.impl, err)) + panic(fmt.Sprintf("%T.MknodAt() consumed all path components and returned %v", rp.mount.fs.impl, err)) } } if !rp.handleError(err) { @@ -350,6 +351,33 @@ func (vfs *VirtualFilesystem) MknodAt(ctx context.Context, creds *auth.Credentia } } +// BoundEndpointAt gets the bound endpoint at the given path, if one exists. +func (vfs *VirtualFilesystem) BoundEndpointAt(ctx context.Context, creds *auth.Credentials, pop *PathOperation) (transport.BoundEndpoint, error) { + if !pop.Path.Begin.Ok() { + if pop.Path.Absolute { + return nil, syserror.ECONNREFUSED + } + return nil, syserror.ENOENT + } + rp := vfs.getResolvingPath(creds, pop) + for { + bep, err := rp.mount.fs.impl.BoundEndpointAt(ctx, rp) + if err == nil { + vfs.putResolvingPath(rp) + return bep, nil + } + if checkInvariants { + if rp.canHandleError(err) && rp.Done() { + panic(fmt.Sprintf("%T.BoundEndpointAt() consumed all path components and returned %v", rp.mount.fs.impl, err)) + } + } + if !rp.handleError(err) { + vfs.putResolvingPath(rp) + return nil, err + } + } +} + // OpenAt returns a FileDescription providing access to the file at the given // path. A reference is taken on the returned FileDescription. func (vfs *VirtualFilesystem) OpenAt(ctx context.Context, creds *auth.Credentials, pop *PathOperation, opts *OpenOptions) (*FileDescription, error) { @@ -494,7 +522,7 @@ func (vfs *VirtualFilesystem) RenameAt(ctx context.Context, creds *auth.Credenti } if checkInvariants { if rp.canHandleError(err) && rp.Done() { - panic(fmt.Sprintf("%T.RenameAt() consumed all path components and returned %T", rp.mount.fs.impl, err)) + panic(fmt.Sprintf("%T.RenameAt() consumed all path components and returned %v", rp.mount.fs.impl, err)) } } if !rp.handleError(err) { @@ -527,7 +555,7 @@ func (vfs *VirtualFilesystem) RmdirAt(ctx context.Context, creds *auth.Credentia } if checkInvariants { if rp.canHandleError(err) && rp.Done() { - panic(fmt.Sprintf("%T.RmdirAt() consumed all path components and returned %T", rp.mount.fs.impl, err)) + panic(fmt.Sprintf("%T.RmdirAt() consumed all path components and returned %v", rp.mount.fs.impl, err)) } } if !rp.handleError(err) { @@ -608,7 +636,7 @@ func (vfs *VirtualFilesystem) SymlinkAt(ctx context.Context, creds *auth.Credent } if checkInvariants { if rp.canHandleError(err) && rp.Done() { - panic(fmt.Sprintf("%T.SymlinkAt() consumed all path components and returned %T", rp.mount.fs.impl, err)) + panic(fmt.Sprintf("%T.SymlinkAt() consumed all path components and returned %v", rp.mount.fs.impl, err)) } } if !rp.handleError(err) { @@ -640,7 +668,7 @@ func (vfs *VirtualFilesystem) UnlinkAt(ctx context.Context, creds *auth.Credenti } if checkInvariants { if rp.canHandleError(err) && rp.Done() { - panic(fmt.Sprintf("%T.UnlinkAt() consumed all path components and returned %T", rp.mount.fs.impl, err)) + panic(fmt.Sprintf("%T.UnlinkAt() consumed all path components and returned %v", rp.mount.fs.impl, err)) } } if !rp.handleError(err) { diff --git a/pkg/syserror/syserror.go b/pkg/syserror/syserror.go index 4b5a0fca6..f86db0999 100644 --- a/pkg/syserror/syserror.go +++ b/pkg/syserror/syserror.go @@ -27,6 +27,7 @@ import ( var ( E2BIG = error(syscall.E2BIG) EACCES = error(syscall.EACCES) + EADDRINUSE = error(syscall.EADDRINUSE) EAGAIN = error(syscall.EAGAIN) EBADF = error(syscall.EBADF) EBADFD = error(syscall.EBADFD) -- cgit v1.2.3 From 5b2396d244ed6283d928a72bdd4cc58d78ef3175 Mon Sep 17 00:00:00 2001 From: Dean Deng Date: Thu, 2 Apr 2020 17:06:19 -0700 Subject: Fix typo in TODO comments. PiperOrigin-RevId: 304508083 --- pkg/sentry/fs/proc/mounts.go | 3 ++- pkg/sentry/fsimpl/tmpfs/filesystem.go | 6 +++--- pkg/sentry/fsimpl/tmpfs/stat_test.go | 4 ++-- pkg/sentry/fsimpl/tmpfs/tmpfs.go | 2 +- pkg/sentry/socket/netstack/netstack.go | 2 +- pkg/sentry/vfs/mount.go | 3 ++- test/syscalls/linux/socket_inet_loopback.cc | 2 +- 7 files changed, 12 insertions(+), 10 deletions(-) (limited to 'pkg/sentry/fsimpl/tmpfs/filesystem.go') diff --git a/pkg/sentry/fs/proc/mounts.go b/pkg/sentry/fs/proc/mounts.go index 94deb553b..1fc9c703c 100644 --- a/pkg/sentry/fs/proc/mounts.go +++ b/pkg/sentry/fs/proc/mounts.go @@ -170,7 +170,8 @@ func superBlockOpts(mountPath string, msrc *fs.MountSource) string { // NOTE(b/147673608): If the mount is a cgroup, we also need to include // the cgroup name in the options. For now we just read that from the // path. - // TODO(gvisor.dev/issues/190): Once gVisor has full cgroup support, we + // + // TODO(gvisor.dev/issue/190): Once gVisor has full cgroup support, we // should get this value from the cgroup itself, and not rely on the // path. if msrc.FilesystemType == "cgroup" { diff --git a/pkg/sentry/fsimpl/tmpfs/filesystem.go b/pkg/sentry/fsimpl/tmpfs/filesystem.go index e678ecc37..4cf27bf13 100644 --- a/pkg/sentry/fsimpl/tmpfs/filesystem.go +++ b/pkg/sentry/fsimpl/tmpfs/filesystem.go @@ -57,7 +57,7 @@ afterSymlink: } next := nextVFSD.Impl().(*dentry) if symlink, ok := next.inode.impl.(*symlink); ok && rp.ShouldFollowSymlink() { - // TODO(gvisor.dev/issues/1197): Symlink traversals updates + // TODO(gvisor.dev/issue/1197): Symlink traversals updates // access time. if err := rp.HandleSymlink(symlink.target); err != nil { return nil, err @@ -515,7 +515,7 @@ func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa oldParent.inode.decLinksLocked() newParent.inode.incLinksLocked() } - // TODO(gvisor.dev/issues/1197): Update timestamps and parent directory + // TODO(gvisor.dev/issue/1197): Update timestamps and parent directory // sizes. vfsObj.CommitRenameReplaceDentry(renamedVFSD, &newParent.vfsd, newName, replacedVFSD) return nil @@ -600,7 +600,7 @@ func (fs *filesystem) StatFSAt(ctx context.Context, rp *vfs.ResolvingPath) (linu if err != nil { return linux.Statfs{}, err } - // TODO(gvisor.dev/issues/1197): Actually implement statfs. + // TODO(gvisor.dev/issue/1197): Actually implement statfs. return linux.Statfs{}, syserror.ENOSYS } diff --git a/pkg/sentry/fsimpl/tmpfs/stat_test.go b/pkg/sentry/fsimpl/tmpfs/stat_test.go index ebe035dee..3e02e7190 100644 --- a/pkg/sentry/fsimpl/tmpfs/stat_test.go +++ b/pkg/sentry/fsimpl/tmpfs/stat_test.go @@ -29,7 +29,7 @@ func TestStatAfterCreate(t *testing.T) { mode := linux.FileMode(0644) // Run with different file types. - // TODO(gvisor.dev/issues/1197): Also test symlinks and sockets. + // TODO(gvisor.dev/issue/1197): Also test symlinks and sockets. for _, typ := range []string{"file", "dir", "pipe"} { t.Run(fmt.Sprintf("type=%q", typ), func(t *testing.T) { var ( @@ -169,7 +169,7 @@ func TestSetStat(t *testing.T) { mode := linux.FileMode(0644) // Run with different file types. - // TODO(gvisor.dev/issues/1197): Also test symlinks and sockets. + // TODO(gvisor.dev/issue/1197): Also test symlinks and sockets. for _, typ := range []string{"file", "dir", "pipe"} { t.Run(fmt.Sprintf("type=%q", typ), func(t *testing.T) { var ( diff --git a/pkg/sentry/fsimpl/tmpfs/tmpfs.go b/pkg/sentry/fsimpl/tmpfs/tmpfs.go index 8bc8818c0..54da15849 100644 --- a/pkg/sentry/fsimpl/tmpfs/tmpfs.go +++ b/pkg/sentry/fsimpl/tmpfs/tmpfs.go @@ -315,7 +315,7 @@ func (i *inode) statTo(stat *linux.Statx) { stat.Atime = linux.NsecToStatxTimestamp(i.atime) stat.Ctime = linux.NsecToStatxTimestamp(i.ctime) stat.Mtime = linux.NsecToStatxTimestamp(i.mtime) - // TODO(gvisor.dev/issues/1197): Device number. + // TODO(gvisor.dev/issue/1197): Device number. switch impl := i.impl.(type) { case *regularFile: stat.Mask |= linux.STATX_SIZE | linux.STATX_BLOCKS diff --git a/pkg/sentry/socket/netstack/netstack.go b/pkg/sentry/socket/netstack/netstack.go index f14c336b9..06a5b53bc 100644 --- a/pkg/sentry/socket/netstack/netstack.go +++ b/pkg/sentry/socket/netstack/netstack.go @@ -663,7 +663,7 @@ func (s *SocketOperations) checkFamily(family uint16, exact bool) *syserr.Error // This is a hack to work around the fact that both IPv4 and IPv6 ANY are // represented by the empty string. // -// TODO(gvisor.dev/issues/1556): remove this function. +// TODO(gvisor.dev/issue/1556): remove this function. func (s *SocketOperations) mapFamily(addr tcpip.FullAddress, family uint16) tcpip.FullAddress { if len(addr.Addr) == 0 && s.family == linux.AF_INET6 && family == linux.AF_INET { addr.Addr = "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff\x00\x00\x00\x00" diff --git a/pkg/sentry/vfs/mount.go b/pkg/sentry/vfs/mount.go index 7792eb1a0..1b8ecc415 100644 --- a/pkg/sentry/vfs/mount.go +++ b/pkg/sentry/vfs/mount.go @@ -835,7 +835,8 @@ func superBlockOpts(mountPath string, mnt *Mount) string { // NOTE(b/147673608): If the mount is a cgroup, we also need to include // the cgroup name in the options. For now we just read that from the // path. - // TODO(gvisor.dev/issues/190): Once gVisor has full cgroup support, we + // + // TODO(gvisor.dev/issue/190): Once gVisor has full cgroup support, we // should get this value from the cgroup itself, and not rely on the // path. if mnt.fs.FilesystemType().Name() == "cgroup" { diff --git a/test/syscalls/linux/socket_inet_loopback.cc b/test/syscalls/linux/socket_inet_loopback.cc index 16888de2a..2ffc86382 100644 --- a/test/syscalls/linux/socket_inet_loopback.cc +++ b/test/syscalls/linux/socket_inet_loopback.cc @@ -234,7 +234,7 @@ TEST_P(DualStackSocketTest, AddressOperations) { } } -// TODO(gvisor.dev/issues/1556): uncomment V4MappedAny. +// TODO(gvisor.dev/issue/1556): uncomment V4MappedAny. INSTANTIATE_TEST_SUITE_P( All, DualStackSocketTest, ::testing::Combine( -- cgit v1.2.3 From dd3bc499970c22ebbd270030b4564e6b8e4e929e Mon Sep 17 00:00:00 2001 From: Fabricio Voznika Date: Thu, 2 Apr 2020 19:37:41 -0700 Subject: Add NAME_MAX checks and update file times NAME_MAX should be enforced per filesystem implementation because other file systems may not have the same restriction. Gofer filesystem now keeps a reference to the kernel clock to avoid lookup in the Context on file access to update atime. Update access, modification, and status change times in tmpfs. Updates #1197, #1198. PiperOrigin-RevId: 304527148 --- pkg/sentry/fsimpl/gofer/directory.go | 7 +++- pkg/sentry/fsimpl/gofer/filesystem.go | 13 ++++++-- pkg/sentry/fsimpl/gofer/gofer.go | 22 ++++++------- pkg/sentry/fsimpl/gofer/regular_file.go | 7 ++-- pkg/sentry/fsimpl/gofer/special_file.go | 4 +-- pkg/sentry/fsimpl/gofer/symlink.go | 2 +- pkg/sentry/fsimpl/gofer/time.go | 39 +++++++++++----------- pkg/sentry/fsimpl/kernfs/filesystem.go | 9 ++++++ pkg/sentry/fsimpl/tmpfs/directory.go | 2 ++ pkg/sentry/fsimpl/tmpfs/filesystem.go | 25 +++++++++++++-- pkg/sentry/fsimpl/tmpfs/regular_file.go | 4 ++- pkg/sentry/fsimpl/tmpfs/tmpfs.go | 57 ++++++++++++++++++++++++++++++--- 12 files changed, 139 insertions(+), 52 deletions(-) (limited to 'pkg/sentry/fsimpl/tmpfs/filesystem.go') diff --git a/pkg/sentry/fsimpl/gofer/directory.go b/pkg/sentry/fsimpl/gofer/directory.go index 5dbfc6250..49d9f859b 100644 --- a/pkg/sentry/fsimpl/gofer/directory.go +++ b/pkg/sentry/fsimpl/gofer/directory.go @@ -56,14 +56,19 @@ func (fd *directoryFD) IterDirents(ctx context.Context, cb vfs.IterDirentsCallba fd.mu.Lock() defer fd.mu.Unlock() + d := fd.dentry() if fd.dirents == nil { - ds, err := fd.dentry().getDirents(ctx) + ds, err := d.getDirents(ctx) if err != nil { return err } fd.dirents = ds } + if d.fs.opts.interop != InteropModeShared { + d.touchAtime(fd.vfsfd.Mount()) + } + for fd.off < int64(len(fd.dirents)) { if err := cb.Handle(fd.dirents[fd.off]); err != nil { return err diff --git a/pkg/sentry/fsimpl/gofer/filesystem.go b/pkg/sentry/fsimpl/gofer/filesystem.go index 269624362..305228bda 100644 --- a/pkg/sentry/fsimpl/gofer/filesystem.go +++ b/pkg/sentry/fsimpl/gofer/filesystem.go @@ -356,7 +356,9 @@ func (fs *filesystem) doCreateAt(ctx context.Context, rp *vfs.ResolvingPath, dir if err := create(parent, name); err != nil { return err } - parent.touchCMtime(ctx) + if fs.opts.interop != InteropModeShared { + parent.touchCMtime() + } delete(parent.negativeChildren, name) parent.dirents = nil return nil @@ -454,7 +456,7 @@ func (fs *filesystem) unlinkAt(ctx context.Context, rp *vfs.ResolvingPath, dir b return err } if fs.opts.interop != InteropModeShared { - parent.touchCMtime(ctx) + parent.touchCMtime() if dir { parent.decLinks() } @@ -802,7 +804,6 @@ func (d *dentry) createAndOpenChildLocked(ctx context.Context, rp *vfs.Resolving d.IncRef() // reference held by child on its parent d d.vfsd.InsertChild(&child.vfsd, name) if d.fs.opts.interop != InteropModeShared { - d.touchCMtime(ctx) delete(d.negativeChildren, name) d.dirents = nil } @@ -834,6 +835,9 @@ func (d *dentry) createAndOpenChildLocked(ctx context.Context, rp *vfs.Resolving } childVFSFD = &fd.vfsfd } + if d.fs.opts.interop != InteropModeShared { + d.touchCMtime() + } return childVFSFD, nil } @@ -975,6 +979,9 @@ func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa oldParent.decLinks() newParent.incLinks() } + oldParent.touchCMtime() + newParent.touchCMtime() + renamed.touchCtime() } vfsObj.CommitRenameReplaceDentry(&renamed.vfsd, &newParent.vfsd, newName, replacedVFSD) return nil diff --git a/pkg/sentry/fsimpl/gofer/gofer.go b/pkg/sentry/fsimpl/gofer/gofer.go index 8e41b6b1c..adee8bb60 100644 --- a/pkg/sentry/fsimpl/gofer/gofer.go +++ b/pkg/sentry/fsimpl/gofer/gofer.go @@ -44,6 +44,7 @@ import ( "gvisor.dev/gvisor/pkg/p9" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" + ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/pgalloc" "gvisor.dev/gvisor/pkg/sentry/vfs" @@ -72,6 +73,9 @@ type filesystem struct { // client is the client used by this filesystem. client is immutable. client *p9.Client + // clock is a realtime clock used to set timestamps in file operations. + clock ktime.Clock + // uid and gid are the effective KUID and KGID of the filesystem's creator, // and are used as the owner and group for files that don't specify one. // uid and gid are immutable. @@ -376,6 +380,7 @@ func (fstype FilesystemType) GetFilesystem(ctx context.Context, vfsObj *vfs.Virt uid: creds.EffectiveKUID, gid: creds.EffectiveKGID, client: client, + clock: ktime.RealtimeClockFromContext(ctx), dentries: make(map[*dentry]struct{}), specialFileFDs: make(map[*specialFileFD]struct{}), } @@ -779,10 +784,7 @@ func (d *dentry) setStat(ctx context.Context, creds *auth.Credentials, stat *lin // data, so there's no cache to truncate either.) return nil } - now, haveNow := nowFromContext(ctx) - if !haveNow { - ctx.Warningf("gofer.dentry.setStat: current time not available") - } + now := d.fs.clock.Now().Nanoseconds() if stat.Mask&linux.STATX_MODE != 0 { atomic.StoreUint32(&d.mode, d.fileType()|uint32(stat.Mode)) } @@ -794,25 +796,19 @@ func (d *dentry) setStat(ctx context.Context, creds *auth.Credentials, stat *lin } if setLocalAtime { if stat.Atime.Nsec == linux.UTIME_NOW { - if haveNow { - atomic.StoreInt64(&d.atime, now) - } + atomic.StoreInt64(&d.atime, now) } else { atomic.StoreInt64(&d.atime, dentryTimestampFromStatx(stat.Atime)) } } if setLocalMtime { if stat.Mtime.Nsec == linux.UTIME_NOW { - if haveNow { - atomic.StoreInt64(&d.mtime, now) - } + atomic.StoreInt64(&d.mtime, now) } else { atomic.StoreInt64(&d.mtime, dentryTimestampFromStatx(stat.Mtime)) } } - if haveNow { - atomic.StoreInt64(&d.ctime, now) - } + atomic.StoreInt64(&d.ctime, now) if stat.Mask&linux.STATX_SIZE != 0 { d.dataMu.Lock() oldSize := d.size diff --git a/pkg/sentry/fsimpl/gofer/regular_file.go b/pkg/sentry/fsimpl/gofer/regular_file.go index 3593eb1d5..857f7c74e 100644 --- a/pkg/sentry/fsimpl/gofer/regular_file.go +++ b/pkg/sentry/fsimpl/gofer/regular_file.go @@ -104,7 +104,7 @@ func (fd *regularFileFD) PRead(ctx context.Context, dst usermem.IOSequence, offs putDentryReadWriter(rw) if d.fs.opts.interop != InteropModeShared { // Compare Linux's mm/filemap.c:do_generic_file_read() => file_accessed(). - d.touchAtime(ctx, fd.vfsfd.Mount()) + d.touchAtime(fd.vfsfd.Mount()) } return n, err } @@ -139,10 +139,7 @@ func (fd *regularFileFD) PWrite(ctx context.Context, src usermem.IOSequence, off // Compare Linux's mm/filemap.c:__generic_file_write_iter() => // file_update_time(). This is d.touchCMtime(), but without locking // d.metadataMu (recursively). - if now, ok := nowFromContext(ctx); ok { - atomic.StoreInt64(&d.mtime, now) - atomic.StoreInt64(&d.ctime, now) - } + d.touchCMtimeLocked() } if fd.vfsfd.StatusFlags()&linux.O_DIRECT != 0 { // Write dirty cached pages that will be touched by the write back to diff --git a/pkg/sentry/fsimpl/gofer/special_file.go b/pkg/sentry/fsimpl/gofer/special_file.go index 274f7346f..507e0e276 100644 --- a/pkg/sentry/fsimpl/gofer/special_file.go +++ b/pkg/sentry/fsimpl/gofer/special_file.go @@ -76,7 +76,7 @@ func (fd *specialFileFD) PRead(ctx context.Context, dst usermem.IOSequence, offs // hold here since specialFileFD doesn't client-cache data. Just buffer the // read instead. if d := fd.dentry(); d.fs.opts.interop != InteropModeShared { - d.touchAtime(ctx, fd.vfsfd.Mount()) + d.touchAtime(fd.vfsfd.Mount()) } buf := make([]byte, dst.NumBytes()) n, err := fd.handle.readToBlocksAt(ctx, safemem.BlockSeqOf(safemem.BlockFromSafeSlice(buf)), uint64(offset)) @@ -117,7 +117,7 @@ func (fd *specialFileFD) PWrite(ctx context.Context, src usermem.IOSequence, off // Do a buffered write. See rationale in PRead. if d := fd.dentry(); d.fs.opts.interop != InteropModeShared { - d.touchCMtime(ctx) + d.touchCMtime() } buf := make([]byte, src.NumBytes()) // Don't do partial writes if we get a partial read from src. diff --git a/pkg/sentry/fsimpl/gofer/symlink.go b/pkg/sentry/fsimpl/gofer/symlink.go index adf43be60..2ec819f86 100644 --- a/pkg/sentry/fsimpl/gofer/symlink.go +++ b/pkg/sentry/fsimpl/gofer/symlink.go @@ -27,7 +27,7 @@ func (d *dentry) isSymlink() bool { // Precondition: d.isSymlink(). func (d *dentry) readlink(ctx context.Context, mnt *vfs.Mount) (string, error) { if d.fs.opts.interop != InteropModeShared { - d.touchAtime(ctx, mnt) + d.touchAtime(mnt) d.dataMu.Lock() if d.haveTarget { target := d.target diff --git a/pkg/sentry/fsimpl/gofer/time.go b/pkg/sentry/fsimpl/gofer/time.go index 7598ec6a8..2608e7e1d 100644 --- a/pkg/sentry/fsimpl/gofer/time.go +++ b/pkg/sentry/fsimpl/gofer/time.go @@ -18,8 +18,6 @@ import ( "sync/atomic" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/context" - ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/vfs" ) @@ -38,23 +36,12 @@ func statxTimestampFromDentry(ns int64) linux.StatxTimestamp { } } -func nowFromContext(ctx context.Context) (int64, bool) { - if clock := ktime.RealtimeClockFromContext(ctx); clock != nil { - return clock.Now().Nanoseconds(), true - } - return 0, false -} - // Preconditions: fs.interop != InteropModeShared. -func (d *dentry) touchAtime(ctx context.Context, mnt *vfs.Mount) { +func (d *dentry) touchAtime(mnt *vfs.Mount) { if err := mnt.CheckBeginWrite(); err != nil { return } - now, ok := nowFromContext(ctx) - if !ok { - mnt.EndWrite() - return - } + now := d.fs.clock.Now().Nanoseconds() d.metadataMu.Lock() atomic.StoreInt64(&d.atime, now) d.metadataMu.Unlock() @@ -63,13 +50,25 @@ func (d *dentry) touchAtime(ctx context.Context, mnt *vfs.Mount) { // Preconditions: fs.interop != InteropModeShared. The caller has successfully // called vfs.Mount.CheckBeginWrite(). -func (d *dentry) touchCMtime(ctx context.Context) { - now, ok := nowFromContext(ctx) - if !ok { - return - } +func (d *dentry) touchCtime() { + now := d.fs.clock.Now().Nanoseconds() + d.metadataMu.Lock() + atomic.StoreInt64(&d.ctime, now) + d.metadataMu.Unlock() +} + +// Preconditions: fs.interop != InteropModeShared. The caller has successfully +// called vfs.Mount.CheckBeginWrite(). +func (d *dentry) touchCMtime() { + now := d.fs.clock.Now().Nanoseconds() d.metadataMu.Lock() atomic.StoreInt64(&d.mtime, now) atomic.StoreInt64(&d.ctime, now) d.metadataMu.Unlock() } + +func (d *dentry) touchCMtimeLocked() { + now := d.fs.clock.Now().Nanoseconds() + atomic.StoreInt64(&d.mtime, now) + atomic.StoreInt64(&d.ctime, now) +} diff --git a/pkg/sentry/fsimpl/kernfs/filesystem.go b/pkg/sentry/fsimpl/kernfs/filesystem.go index a429fa23d..89f5da3d4 100644 --- a/pkg/sentry/fsimpl/kernfs/filesystem.go +++ b/pkg/sentry/fsimpl/kernfs/filesystem.go @@ -63,6 +63,9 @@ afterSymlink: rp.Advance() return nextVFSD, nil } + if len(name) > linux.NAME_MAX { + return nil, syserror.ENAMETOOLONG + } d.dirMu.Lock() nextVFSD, err := rp.ResolveChild(vfsd, name) if err != nil { @@ -191,6 +194,9 @@ func checkCreateLocked(ctx context.Context, rp *vfs.ResolvingPath, parentVFSD *v if pc == "." || pc == ".." { return "", syserror.EEXIST } + if len(pc) > linux.NAME_MAX { + return "", syserror.ENAMETOOLONG + } childVFSD, err := rp.ResolveChild(parentVFSD, pc) if err != nil { return "", err @@ -433,6 +439,9 @@ afterTrailingSymlink: if pc == "." || pc == ".." { return nil, syserror.EISDIR } + if len(pc) > linux.NAME_MAX { + return nil, syserror.ENAMETOOLONG + } // Determine whether or not we need to create a file. childVFSD, err := rp.ResolveChild(parentVFSD, pc) if err != nil { diff --git a/pkg/sentry/fsimpl/tmpfs/directory.go b/pkg/sentry/fsimpl/tmpfs/directory.go index 37c75ab64..45712c9b9 100644 --- a/pkg/sentry/fsimpl/tmpfs/directory.go +++ b/pkg/sentry/fsimpl/tmpfs/directory.go @@ -68,6 +68,8 @@ func (fd *directoryFD) IterDirents(ctx context.Context, cb vfs.IterDirentsCallba fs.mu.Lock() defer fs.mu.Unlock() + fd.inode().touchAtime(fd.vfsfd.Mount()) + if fd.off == 0 { if err := cb.Handle(vfs.Dirent{ Name: ".", diff --git a/pkg/sentry/fsimpl/tmpfs/filesystem.go b/pkg/sentry/fsimpl/tmpfs/filesystem.go index 4cf27bf13..1978af69c 100644 --- a/pkg/sentry/fsimpl/tmpfs/filesystem.go +++ b/pkg/sentry/fsimpl/tmpfs/filesystem.go @@ -46,6 +46,9 @@ func stepLocked(rp *vfs.ResolvingPath, d *dentry) (*dentry, error) { return nil, err } afterSymlink: + if len(rp.Component()) > linux.NAME_MAX { + return nil, syserror.ENAMETOOLONG + } nextVFSD, err := rp.ResolveComponent(&d.vfsd) if err != nil { return nil, err @@ -133,6 +136,9 @@ func (fs *filesystem) doCreateAt(rp *vfs.ResolvingPath, dir bool, create func(pa if name == "." || name == ".." { return syserror.EEXIST } + if len(name) > linux.NAME_MAX { + return syserror.ENAMETOOLONG + } // Call parent.vfsd.Child() instead of stepLocked() or rp.ResolveChild(), // because if the child exists we want to return EEXIST immediately instead // of attempting symlink/mount traversal. @@ -153,7 +159,11 @@ func (fs *filesystem) doCreateAt(rp *vfs.ResolvingPath, dir bool, create func(pa return err } defer mnt.EndWrite() - return create(parent, name) + if err := create(parent, name); err != nil { + return err + } + parent.inode.touchCMtime() + return nil } // AccessAt implements vfs.Filesystem.Impl.AccessAt. @@ -328,7 +338,12 @@ afterTrailingSymlink: child := fs.newDentry(fs.newRegularFile(rp.Credentials(), opts.Mode)) parent.vfsd.InsertChild(&child.vfsd, name) parent.inode.impl.(*directory).childList.PushBack(child) - return child.open(ctx, rp, &opts, true) + fd, err := child.open(ctx, rp, &opts, true) + if err != nil { + return nil, err + } + parent.inode.touchCMtime() + return fd, nil } if err != nil { return nil, err @@ -398,6 +413,7 @@ func (fs *filesystem) ReadlinkAt(ctx context.Context, rp *vfs.ResolvingPath) (st if !ok { return "", syserror.EINVAL } + symlink.inode.touchAtime(rp.Mount()) return symlink.target, nil } @@ -515,6 +531,9 @@ func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa oldParent.inode.decLinksLocked() newParent.inode.incLinksLocked() } + oldParent.inode.touchCMtime() + newParent.inode.touchCMtime() + renamed.inode.touchCtime() // TODO(gvisor.dev/issue/1197): Update timestamps and parent directory // sizes. vfsObj.CommitRenameReplaceDentry(renamedVFSD, &newParent.vfsd, newName, replacedVFSD) @@ -565,6 +584,7 @@ func (fs *filesystem) RmdirAt(ctx context.Context, rp *vfs.ResolvingPath) error parent.inode.decLinksLocked() // from child's ".." child.inode.decLinksLocked() vfsObj.CommitDeleteDentry(childVFSD) + parent.inode.touchCMtime() return nil } @@ -654,6 +674,7 @@ func (fs *filesystem) UnlinkAt(ctx context.Context, rp *vfs.ResolvingPath) error parent.inode.impl.(*directory).childList.Remove(child) child.inode.decLinksLocked() vfsObj.CommitDeleteDentry(childVFSD) + parent.inode.touchCMtime() return nil } diff --git a/pkg/sentry/fsimpl/tmpfs/regular_file.go b/pkg/sentry/fsimpl/tmpfs/regular_file.go index 26cd65605..57e5e28ec 100644 --- a/pkg/sentry/fsimpl/tmpfs/regular_file.go +++ b/pkg/sentry/fsimpl/tmpfs/regular_file.go @@ -286,7 +286,8 @@ func (fd *regularFileFD) PRead(ctx context.Context, dst usermem.IOSequence, offs rw := getRegularFileReadWriter(f, offset) n, err := dst.CopyOutFrom(ctx, rw) putRegularFileReadWriter(rw) - return int64(n), err + fd.inode().touchAtime(fd.vfsfd.Mount()) + return n, err } // Read implements vfs.FileDescriptionImpl.Read. @@ -323,6 +324,7 @@ func (fd *regularFileFD) PWrite(ctx context.Context, src usermem.IOSequence, off f.inode.mu.Lock() rw := getRegularFileReadWriter(f, offset) n, err := src.CopyInTo(ctx, rw) + fd.inode().touchCMtimeLocked() f.inode.mu.Unlock() putRegularFileReadWriter(rw) return n, err diff --git a/pkg/sentry/fsimpl/tmpfs/tmpfs.go b/pkg/sentry/fsimpl/tmpfs/tmpfs.go index 54da15849..ad47288f8 100644 --- a/pkg/sentry/fsimpl/tmpfs/tmpfs.go +++ b/pkg/sentry/fsimpl/tmpfs/tmpfs.go @@ -385,28 +385,41 @@ func (i *inode) setStat(ctx context.Context, creds *auth.Credentials, stat *linu return syserror.EINVAL } } + now := i.clock.Now().Nanoseconds() if mask&linux.STATX_ATIME != 0 { - atomic.StoreInt64(&i.atime, stat.Atime.ToNsecCapped()) + if stat.Atime.Nsec == linux.UTIME_NOW { + atomic.StoreInt64(&i.atime, now) + } else { + atomic.StoreInt64(&i.atime, stat.Atime.ToNsecCapped()) + } needsCtimeBump = true } if mask&linux.STATX_MTIME != 0 { - atomic.StoreInt64(&i.mtime, stat.Mtime.ToNsecCapped()) + if stat.Mtime.Nsec == linux.UTIME_NOW { + atomic.StoreInt64(&i.mtime, now) + } else { + atomic.StoreInt64(&i.mtime, stat.Mtime.ToNsecCapped()) + } needsCtimeBump = true // Ignore the mtime bump, since we just set it ourselves. needsMtimeBump = false } if mask&linux.STATX_CTIME != 0 { - atomic.StoreInt64(&i.ctime, stat.Ctime.ToNsecCapped()) + if stat.Ctime.Nsec == linux.UTIME_NOW { + atomic.StoreInt64(&i.ctime, now) + } else { + atomic.StoreInt64(&i.ctime, stat.Ctime.ToNsecCapped()) + } // Ignore the ctime bump, since we just set it ourselves. needsCtimeBump = false } - now := i.clock.Now().Nanoseconds() if needsMtimeBump { atomic.StoreInt64(&i.mtime, now) } if needsCtimeBump { atomic.StoreInt64(&i.ctime, now) } + i.mu.Unlock() return nil } @@ -484,6 +497,42 @@ func (i *inode) isDir() bool { return linux.FileMode(i.mode).FileType() == linux.S_IFDIR } +func (i *inode) touchAtime(mnt *vfs.Mount) { + if err := mnt.CheckBeginWrite(); err != nil { + return + } + now := i.clock.Now().Nanoseconds() + i.mu.Lock() + atomic.StoreInt64(&i.atime, now) + i.mu.Unlock() + mnt.EndWrite() +} + +// Preconditions: The caller has called vfs.Mount.CheckBeginWrite(). +func (i *inode) touchCtime() { + now := i.clock.Now().Nanoseconds() + i.mu.Lock() + atomic.StoreInt64(&i.ctime, now) + i.mu.Unlock() +} + +// Preconditions: The caller has called vfs.Mount.CheckBeginWrite(). +func (i *inode) touchCMtime() { + now := i.clock.Now().Nanoseconds() + i.mu.Lock() + atomic.StoreInt64(&i.mtime, now) + atomic.StoreInt64(&i.ctime, now) + i.mu.Unlock() +} + +// Preconditions: The caller has called vfs.Mount.CheckBeginWrite() and holds +// inode.mu. +func (i *inode) touchCMtimeLocked() { + now := i.clock.Now().Nanoseconds() + atomic.StoreInt64(&i.mtime, now) + atomic.StoreInt64(&i.ctime, now) +} + // fileDescription is embedded by tmpfs implementations of // vfs.FileDescriptionImpl. type fileDescription struct { -- cgit v1.2.3 From 00d9776a4bb1cc1d7125af7d3e54a939a4f3847a Mon Sep 17 00:00:00 2001 From: Dean Deng Date: Mon, 6 Apr 2020 07:30:20 -0700 Subject: Add socket files to tmpfs VFS2. Updates #1476. PiperOrigin-RevId: 305024274 --- pkg/sentry/fsimpl/tmpfs/BUILD | 1 + pkg/sentry/fsimpl/tmpfs/filesystem.go | 20 +++++++++++++++----- pkg/sentry/fsimpl/tmpfs/socket_file.go | 34 ++++++++++++++++++++++++++++++++++ pkg/sentry/fsimpl/tmpfs/tmpfs.go | 4 +++- 4 files changed, 53 insertions(+), 6 deletions(-) create mode 100644 pkg/sentry/fsimpl/tmpfs/socket_file.go (limited to 'pkg/sentry/fsimpl/tmpfs/filesystem.go') diff --git a/pkg/sentry/fsimpl/tmpfs/BUILD b/pkg/sentry/fsimpl/tmpfs/BUILD index 6ea35affb..f2ac23c88 100644 --- a/pkg/sentry/fsimpl/tmpfs/BUILD +++ b/pkg/sentry/fsimpl/tmpfs/BUILD @@ -24,6 +24,7 @@ go_library( "filesystem.go", "named_pipe.go", "regular_file.go", + "socket_file.go", "symlink.go", "tmpfs.go", ], diff --git a/pkg/sentry/fsimpl/tmpfs/filesystem.go b/pkg/sentry/fsimpl/tmpfs/filesystem.go index 1978af69c..5339d7072 100644 --- a/pkg/sentry/fsimpl/tmpfs/filesystem.go +++ b/pkg/sentry/fsimpl/tmpfs/filesystem.go @@ -261,8 +261,7 @@ func (fs *filesystem) MknodAt(ctx context.Context, rp *vfs.ResolvingPath, opts v case linux.S_IFCHR: childInode = fs.newDeviceFile(rp.Credentials(), opts.Mode, vfs.CharDevice, opts.DevMajor, opts.DevMinor) case linux.S_IFSOCK: - // Not yet supported. - return syserror.EPERM + childInode = fs.newSocketFile(rp.Credentials(), opts.Mode, opts.Endpoint) default: return syserror.EINVAL } @@ -396,6 +395,8 @@ func (d *dentry) open(ctx context.Context, rp *vfs.ResolvingPath, opts *vfs.Open return newNamedPipeFD(ctx, impl, rp, &d.vfsd, opts.Flags) case *deviceFile: return rp.VirtualFilesystem().OpenDeviceSpecialFile(ctx, rp.Mount(), &d.vfsd, impl.kind, impl.major, impl.minor, opts) + case *socketFile: + return nil, syserror.ENXIO default: panic(fmt.Sprintf("unknown inode type: %T", d.inode.impl)) } @@ -679,10 +680,19 @@ func (fs *filesystem) UnlinkAt(ctx context.Context, rp *vfs.ResolvingPath) error } // BoundEndpointAt implements FilesystemImpl.BoundEndpointAt. -// -// TODO(gvisor.dev/issue/1476): Implement BoundEndpointAt. func (fs *filesystem) BoundEndpointAt(ctx context.Context, rp *vfs.ResolvingPath) (transport.BoundEndpoint, error) { - return nil, syserror.ECONNREFUSED + fs.mu.RLock() + defer fs.mu.RUnlock() + d, err := resolveLocked(rp) + if err != nil { + return nil, err + } + switch impl := d.inode.impl.(type) { + case *socketFile: + return impl.ep, nil + default: + return nil, syserror.ECONNREFUSED + } } // ListxattrAt implements vfs.FilesystemImpl.ListxattrAt. diff --git a/pkg/sentry/fsimpl/tmpfs/socket_file.go b/pkg/sentry/fsimpl/tmpfs/socket_file.go new file mode 100644 index 000000000..25c2321af --- /dev/null +++ b/pkg/sentry/fsimpl/tmpfs/socket_file.go @@ -0,0 +1,34 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package tmpfs + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/kernel/auth" + "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" +) + +// socketFile is a socket (=S_IFSOCK) tmpfs file. +type socketFile struct { + inode inode + ep transport.BoundEndpoint +} + +func (fs *filesystem) newSocketFile(creds *auth.Credentials, mode linux.FileMode, ep transport.BoundEndpoint) *inode { + file := &socketFile{ep: ep} + file.inode.init(file, fs, creds, mode) + file.inode.nlink = 1 // from parent directory + return &file.inode +} diff --git a/pkg/sentry/fsimpl/tmpfs/tmpfs.go b/pkg/sentry/fsimpl/tmpfs/tmpfs.go index ad47288f8..654e788e3 100644 --- a/pkg/sentry/fsimpl/tmpfs/tmpfs.go +++ b/pkg/sentry/fsimpl/tmpfs/tmpfs.go @@ -331,7 +331,7 @@ func (i *inode) statTo(stat *linux.Statx) { case *deviceFile: stat.RdevMajor = impl.major stat.RdevMinor = impl.minor - case *directory, *namedPipe: + case *socketFile, *directory, *namedPipe: // Nothing to do. default: panic(fmt.Sprintf("unknown inode type: %T", i.impl)) @@ -479,6 +479,8 @@ func (i *inode) direntType() uint8 { return linux.DT_DIR case *symlink: return linux.DT_LNK + case *socketFile: + return linux.DT_SOCK case *deviceFile: switch impl.kind { case vfs.BlockDevice: -- cgit v1.2.3 From 09ddb5a4262c39744643b612109dd12dcce176a8 Mon Sep 17 00:00:00 2001 From: Dean Deng Date: Fri, 10 Apr 2020 19:01:39 -0700 Subject: Port extended attributes to VFS2. As in VFS1, we only support the user.* namespace. Plumbing is added to tmpfs and goferfs. Note that because of the slightly different order of checks between VFS2 and Linux, one of the xattr tests needs to be relaxed slightly. Fixes #2363. PiperOrigin-RevId: 305985121 --- pkg/sentry/fsimpl/ext/filesystem.go | 4 +- pkg/sentry/fsimpl/gofer/filesystem.go | 12 ++-- pkg/sentry/fsimpl/gofer/gofer.go | 58 +++++++++++---- pkg/sentry/fsimpl/gofer/p9file.go | 14 ++++ pkg/sentry/fsimpl/kernfs/filesystem.go | 4 +- pkg/sentry/fsimpl/tmpfs/BUILD | 1 + pkg/sentry/fsimpl/tmpfs/filesystem.go | 24 +++---- pkg/sentry/fsimpl/tmpfs/tmpfs.go | 77 ++++++++++++++++++++ pkg/sentry/syscalls/linux/vfs2/xattr.go | 13 ++-- pkg/sentry/vfs/anonfs.go | 4 +- pkg/sentry/vfs/file_description.go | 32 ++++++--- pkg/sentry/vfs/file_description_impl_util.go | 4 +- pkg/sentry/vfs/filesystem.go | 24 ++++++- pkg/sentry/vfs/memxattr/BUILD | 15 ++++ pkg/sentry/vfs/memxattr/xattr.go | 102 +++++++++++++++++++++++++++ pkg/sentry/vfs/options.go | 14 ++++ pkg/sentry/vfs/vfs.go | 8 +-- test/syscalls/linux/xattr.cc | 8 +-- 18 files changed, 350 insertions(+), 68 deletions(-) create mode 100644 pkg/sentry/vfs/memxattr/BUILD create mode 100644 pkg/sentry/vfs/memxattr/xattr.go (limited to 'pkg/sentry/fsimpl/tmpfs/filesystem.go') diff --git a/pkg/sentry/fsimpl/ext/filesystem.go b/pkg/sentry/fsimpl/ext/filesystem.go index 48eaccdbc..afea58f65 100644 --- a/pkg/sentry/fsimpl/ext/filesystem.go +++ b/pkg/sentry/fsimpl/ext/filesystem.go @@ -476,7 +476,7 @@ func (fs *filesystem) BoundEndpointAt(ctx context.Context, rp *vfs.ResolvingPath } // ListxattrAt implements vfs.FilesystemImpl.ListxattrAt. -func (fs *filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath) ([]string, error) { +func (fs *filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath, size uint64) ([]string, error) { _, _, err := fs.walk(rp, false) if err != nil { return nil, err @@ -485,7 +485,7 @@ func (fs *filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath) ([ } // GetxattrAt implements vfs.FilesystemImpl.GetxattrAt. -func (fs *filesystem) GetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, name string) (string, error) { +func (fs *filesystem) GetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.GetxattrOptions) (string, error) { _, _, err := fs.walk(rp, false) if err != nil { return "", err diff --git a/pkg/sentry/fsimpl/gofer/filesystem.go b/pkg/sentry/fsimpl/gofer/filesystem.go index 137260898..cd744bf5e 100644 --- a/pkg/sentry/fsimpl/gofer/filesystem.go +++ b/pkg/sentry/fsimpl/gofer/filesystem.go @@ -1080,7 +1080,7 @@ func (fs *filesystem) BoundEndpointAt(ctx context.Context, rp *vfs.ResolvingPath } // ListxattrAt implements vfs.FilesystemImpl.ListxattrAt. -func (fs *filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath) ([]string, error) { +func (fs *filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath, size uint64) ([]string, error) { var ds *[]*dentry fs.renameMu.RLock() defer fs.renameMuRUnlockAndCheckCaching(&ds) @@ -1088,11 +1088,11 @@ func (fs *filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath) ([ if err != nil { return nil, err } - return d.listxattr(ctx) + return d.listxattr(ctx, rp.Credentials(), size) } // GetxattrAt implements vfs.FilesystemImpl.GetxattrAt. -func (fs *filesystem) GetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, name string) (string, error) { +func (fs *filesystem) GetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.GetxattrOptions) (string, error) { var ds *[]*dentry fs.renameMu.RLock() defer fs.renameMuRUnlockAndCheckCaching(&ds) @@ -1100,7 +1100,7 @@ func (fs *filesystem) GetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, nam if err != nil { return "", err } - return d.getxattr(ctx, name) + return d.getxattr(ctx, rp.Credentials(), &opts) } // SetxattrAt implements vfs.FilesystemImpl.SetxattrAt. @@ -1112,7 +1112,7 @@ func (fs *filesystem) SetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, opt if err != nil { return err } - return d.setxattr(ctx, &opts) + return d.setxattr(ctx, rp.Credentials(), &opts) } // RemovexattrAt implements vfs.FilesystemImpl.RemovexattrAt. @@ -1124,7 +1124,7 @@ func (fs *filesystem) RemovexattrAt(ctx context.Context, rp *vfs.ResolvingPath, if err != nil { return err } - return d.removexattr(ctx, name) + return d.removexattr(ctx, rp.Credentials(), name) } // PrependPath implements vfs.FilesystemImpl.PrependPath. diff --git a/pkg/sentry/fsimpl/gofer/gofer.go b/pkg/sentry/fsimpl/gofer/gofer.go index bdf11fa65..2485cdb53 100644 --- a/pkg/sentry/fsimpl/gofer/gofer.go +++ b/pkg/sentry/fsimpl/gofer/gofer.go @@ -34,6 +34,7 @@ package gofer import ( "fmt" "strconv" + "strings" "sync" "sync/atomic" "syscall" @@ -1024,21 +1025,50 @@ func (d *dentry) setDeleted() { atomic.StoreUint32(&d.deleted, 1) } -func (d *dentry) listxattr(ctx context.Context) ([]string, error) { - return nil, syserror.ENOTSUP +// We only support xattrs prefixed with "user." (see b/148380782). Currently, +// there is no need to expose any other xattrs through a gofer. +func (d *dentry) listxattr(ctx context.Context, creds *auth.Credentials, size uint64) ([]string, error) { + xattrMap, err := d.file.listXattr(ctx, size) + if err != nil { + return nil, err + } + xattrs := make([]string, 0, len(xattrMap)) + for x := range xattrMap { + if strings.HasPrefix(x, linux.XATTR_USER_PREFIX) { + xattrs = append(xattrs, x) + } + } + return xattrs, nil } -func (d *dentry) getxattr(ctx context.Context, name string) (string, error) { - // TODO(jamieliu): add vfs.GetxattrOptions.Size - return d.file.getXattr(ctx, name, linux.XATTR_SIZE_MAX) +func (d *dentry) getxattr(ctx context.Context, creds *auth.Credentials, opts *vfs.GetxattrOptions) (string, error) { + if err := d.checkPermissions(creds, vfs.MayRead); err != nil { + return "", err + } + if !strings.HasPrefix(opts.Name, linux.XATTR_USER_PREFIX) { + return "", syserror.EOPNOTSUPP + } + return d.file.getXattr(ctx, opts.Name, opts.Size) } -func (d *dentry) setxattr(ctx context.Context, opts *vfs.SetxattrOptions) error { +func (d *dentry) setxattr(ctx context.Context, creds *auth.Credentials, opts *vfs.SetxattrOptions) error { + if err := d.checkPermissions(creds, vfs.MayWrite); err != nil { + return err + } + if !strings.HasPrefix(opts.Name, linux.XATTR_USER_PREFIX) { + return syserror.EOPNOTSUPP + } return d.file.setXattr(ctx, opts.Name, opts.Value, opts.Flags) } -func (d *dentry) removexattr(ctx context.Context, name string) error { - return syserror.ENOTSUP +func (d *dentry) removexattr(ctx context.Context, creds *auth.Credentials, name string) error { + if err := d.checkPermissions(creds, vfs.MayWrite); err != nil { + return err + } + if !strings.HasPrefix(name, linux.XATTR_USER_PREFIX) { + return syserror.EOPNOTSUPP + } + return d.file.removeXattr(ctx, name) } // Preconditions: d.isRegularFile() || d.isDirectory(). @@ -1189,21 +1219,21 @@ func (fd *fileDescription) SetStat(ctx context.Context, opts vfs.SetStatOptions) } // Listxattr implements vfs.FileDescriptionImpl.Listxattr. -func (fd *fileDescription) Listxattr(ctx context.Context) ([]string, error) { - return fd.dentry().listxattr(ctx) +func (fd *fileDescription) Listxattr(ctx context.Context, size uint64) ([]string, error) { + return fd.dentry().listxattr(ctx, auth.CredentialsFromContext(ctx), size) } // Getxattr implements vfs.FileDescriptionImpl.Getxattr. -func (fd *fileDescription) Getxattr(ctx context.Context, name string) (string, error) { - return fd.dentry().getxattr(ctx, name) +func (fd *fileDescription) Getxattr(ctx context.Context, opts vfs.GetxattrOptions) (string, error) { + return fd.dentry().getxattr(ctx, auth.CredentialsFromContext(ctx), &opts) } // Setxattr implements vfs.FileDescriptionImpl.Setxattr. func (fd *fileDescription) Setxattr(ctx context.Context, opts vfs.SetxattrOptions) error { - return fd.dentry().setxattr(ctx, &opts) + return fd.dentry().setxattr(ctx, auth.CredentialsFromContext(ctx), &opts) } // Removexattr implements vfs.FileDescriptionImpl.Removexattr. func (fd *fileDescription) Removexattr(ctx context.Context, name string) error { - return fd.dentry().removexattr(ctx, name) + return fd.dentry().removexattr(ctx, auth.CredentialsFromContext(ctx), name) } diff --git a/pkg/sentry/fsimpl/gofer/p9file.go b/pkg/sentry/fsimpl/gofer/p9file.go index 755ac2985..87f0b877f 100644 --- a/pkg/sentry/fsimpl/gofer/p9file.go +++ b/pkg/sentry/fsimpl/gofer/p9file.go @@ -85,6 +85,13 @@ func (f p9file) setAttr(ctx context.Context, valid p9.SetAttrMask, attr p9.SetAt return err } +func (f p9file) listXattr(ctx context.Context, size uint64) (map[string]struct{}, error) { + ctx.UninterruptibleSleepStart(false) + xattrs, err := f.file.ListXattr(size) + ctx.UninterruptibleSleepFinish(false) + return xattrs, err +} + func (f p9file) getXattr(ctx context.Context, name string, size uint64) (string, error) { ctx.UninterruptibleSleepStart(false) val, err := f.file.GetXattr(name, size) @@ -99,6 +106,13 @@ func (f p9file) setXattr(ctx context.Context, name, value string, flags uint32) return err } +func (f p9file) removeXattr(ctx context.Context, name string) error { + ctx.UninterruptibleSleepStart(false) + err := f.file.RemoveXattr(name) + ctx.UninterruptibleSleepFinish(false) + return err +} + func (f p9file) allocate(ctx context.Context, mode p9.AllocateMode, offset, length uint64) error { ctx.UninterruptibleSleepStart(false) err := f.file.Allocate(mode, offset, length) diff --git a/pkg/sentry/fsimpl/kernfs/filesystem.go b/pkg/sentry/fsimpl/kernfs/filesystem.go index 4433071aa..baf81b4db 100644 --- a/pkg/sentry/fsimpl/kernfs/filesystem.go +++ b/pkg/sentry/fsimpl/kernfs/filesystem.go @@ -763,7 +763,7 @@ func (fs *Filesystem) BoundEndpointAt(ctx context.Context, rp *vfs.ResolvingPath } // ListxattrAt implements vfs.FilesystemImpl.ListxattrAt. -func (fs *Filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath) ([]string, error) { +func (fs *Filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath, size uint64) ([]string, error) { fs.mu.RLock() _, _, err := fs.walkExistingLocked(ctx, rp) fs.mu.RUnlock() @@ -776,7 +776,7 @@ func (fs *Filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath) ([ } // GetxattrAt implements vfs.FilesystemImpl.GetxattrAt. -func (fs *Filesystem) GetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, name string) (string, error) { +func (fs *Filesystem) GetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.GetxattrOptions) (string, error) { fs.mu.RLock() _, _, err := fs.walkExistingLocked(ctx, rp) fs.mu.RUnlock() diff --git a/pkg/sentry/fsimpl/tmpfs/BUILD b/pkg/sentry/fsimpl/tmpfs/BUILD index f2ac23c88..4e6cd3491 100644 --- a/pkg/sentry/fsimpl/tmpfs/BUILD +++ b/pkg/sentry/fsimpl/tmpfs/BUILD @@ -51,6 +51,7 @@ go_library( "//pkg/sentry/usage", "//pkg/sentry/vfs", "//pkg/sentry/vfs/lock", + "//pkg/sentry/vfs/memxattr", "//pkg/sync", "//pkg/syserror", "//pkg/usermem", diff --git a/pkg/sentry/fsimpl/tmpfs/filesystem.go b/pkg/sentry/fsimpl/tmpfs/filesystem.go index 5339d7072..f4d50d64f 100644 --- a/pkg/sentry/fsimpl/tmpfs/filesystem.go +++ b/pkg/sentry/fsimpl/tmpfs/filesystem.go @@ -696,51 +696,47 @@ func (fs *filesystem) BoundEndpointAt(ctx context.Context, rp *vfs.ResolvingPath } // ListxattrAt implements vfs.FilesystemImpl.ListxattrAt. -func (fs *filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath) ([]string, error) { +func (fs *filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath, size uint64) ([]string, error) { fs.mu.RLock() defer fs.mu.RUnlock() - _, err := resolveLocked(rp) + d, err := resolveLocked(rp) if err != nil { return nil, err } - // TODO(b/127675828): support extended attributes - return nil, syserror.ENOTSUP + return d.inode.listxattr(size) } // GetxattrAt implements vfs.FilesystemImpl.GetxattrAt. -func (fs *filesystem) GetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, name string) (string, error) { +func (fs *filesystem) GetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.GetxattrOptions) (string, error) { fs.mu.RLock() defer fs.mu.RUnlock() - _, err := resolveLocked(rp) + d, err := resolveLocked(rp) if err != nil { return "", err } - // TODO(b/127675828): support extended attributes - return "", syserror.ENOTSUP + return d.inode.getxattr(rp.Credentials(), &opts) } // SetxattrAt implements vfs.FilesystemImpl.SetxattrAt. func (fs *filesystem) SetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.SetxattrOptions) error { fs.mu.RLock() defer fs.mu.RUnlock() - _, err := resolveLocked(rp) + d, err := resolveLocked(rp) if err != nil { return err } - // TODO(b/127675828): support extended attributes - return syserror.ENOTSUP + return d.inode.setxattr(rp.Credentials(), &opts) } // RemovexattrAt implements vfs.FilesystemImpl.RemovexattrAt. func (fs *filesystem) RemovexattrAt(ctx context.Context, rp *vfs.ResolvingPath, name string) error { fs.mu.RLock() defer fs.mu.RUnlock() - _, err := resolveLocked(rp) + d, err := resolveLocked(rp) if err != nil { return err } - // TODO(b/127675828): support extended attributes - return syserror.ENOTSUP + return d.inode.removexattr(rp.Credentials(), name) } // PrependPath implements vfs.FilesystemImpl.PrependPath. diff --git a/pkg/sentry/fsimpl/tmpfs/tmpfs.go b/pkg/sentry/fsimpl/tmpfs/tmpfs.go index 654e788e3..9fa8637d5 100644 --- a/pkg/sentry/fsimpl/tmpfs/tmpfs.go +++ b/pkg/sentry/fsimpl/tmpfs/tmpfs.go @@ -27,6 +27,7 @@ package tmpfs import ( "fmt" "math" + "strings" "sync/atomic" "gvisor.dev/gvisor/pkg/abi/linux" @@ -37,6 +38,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/pgalloc" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/sentry/vfs/lock" + "gvisor.dev/gvisor/pkg/sentry/vfs/memxattr" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" ) @@ -186,6 +188,11 @@ type inode struct { // filesystem.RmdirAt() drops the reference. refs int64 + // xattrs implements extended attributes. + // + // TODO(b/148380782): Support xattrs other than user.* + xattrs memxattr.SimpleExtendedAttributes + // Inode metadata. Writing multiple fields atomically requires holding // mu, othewise atomic operations can be used. mu sync.Mutex @@ -535,6 +542,56 @@ func (i *inode) touchCMtimeLocked() { atomic.StoreInt64(&i.ctime, now) } +func (i *inode) listxattr(size uint64) ([]string, error) { + return i.xattrs.Listxattr(size) +} + +func (i *inode) getxattr(creds *auth.Credentials, opts *vfs.GetxattrOptions) (string, error) { + if err := i.checkPermissions(creds, vfs.MayRead); err != nil { + return "", err + } + if !strings.HasPrefix(opts.Name, linux.XATTR_USER_PREFIX) { + return "", syserror.EOPNOTSUPP + } + if !i.userXattrSupported() { + return "", syserror.ENODATA + } + return i.xattrs.Getxattr(opts) +} + +func (i *inode) setxattr(creds *auth.Credentials, opts *vfs.SetxattrOptions) error { + if err := i.checkPermissions(creds, vfs.MayWrite); err != nil { + return err + } + if !strings.HasPrefix(opts.Name, linux.XATTR_USER_PREFIX) { + return syserror.EOPNOTSUPP + } + if !i.userXattrSupported() { + return syserror.EPERM + } + return i.xattrs.Setxattr(opts) +} + +func (i *inode) removexattr(creds *auth.Credentials, name string) error { + if err := i.checkPermissions(creds, vfs.MayWrite); err != nil { + return err + } + if !strings.HasPrefix(name, linux.XATTR_USER_PREFIX) { + return syserror.EOPNOTSUPP + } + if !i.userXattrSupported() { + return syserror.EPERM + } + return i.xattrs.Removexattr(name) +} + +// Extended attributes in the user.* namespace are only supported for regular +// files and directories. +func (i *inode) userXattrSupported() bool { + filetype := linux.S_IFMT & atomic.LoadUint32(&i.mode) + return filetype == linux.S_IFREG || filetype == linux.S_IFDIR +} + // fileDescription is embedded by tmpfs implementations of // vfs.FileDescriptionImpl. type fileDescription struct { @@ -562,3 +619,23 @@ func (fd *fileDescription) SetStat(ctx context.Context, opts vfs.SetStatOptions) creds := auth.CredentialsFromContext(ctx) return fd.inode().setStat(ctx, creds, &opts.Stat) } + +// Listxattr implements vfs.FileDescriptionImpl.Listxattr. +func (fd *fileDescription) Listxattr(ctx context.Context, size uint64) ([]string, error) { + return fd.inode().listxattr(size) +} + +// Getxattr implements vfs.FileDescriptionImpl.Getxattr. +func (fd *fileDescription) Getxattr(ctx context.Context, opts vfs.GetxattrOptions) (string, error) { + return fd.inode().getxattr(auth.CredentialsFromContext(ctx), &opts) +} + +// Setxattr implements vfs.FileDescriptionImpl.Setxattr. +func (fd *fileDescription) Setxattr(ctx context.Context, opts vfs.SetxattrOptions) error { + return fd.inode().setxattr(auth.CredentialsFromContext(ctx), &opts) +} + +// Removexattr implements vfs.FileDescriptionImpl.Removexattr. +func (fd *fileDescription) Removexattr(ctx context.Context, name string) error { + return fd.inode().removexattr(auth.CredentialsFromContext(ctx), name) +} diff --git a/pkg/sentry/syscalls/linux/vfs2/xattr.go b/pkg/sentry/syscalls/linux/vfs2/xattr.go index 89e9ff4d7..af455d5c1 100644 --- a/pkg/sentry/syscalls/linux/vfs2/xattr.go +++ b/pkg/sentry/syscalls/linux/vfs2/xattr.go @@ -51,7 +51,7 @@ func listxattr(t *kernel.Task, args arch.SyscallArguments, shouldFollowFinalSyml } defer tpop.Release() - names, err := t.Kernel().VFS().ListxattrAt(t, t.Credentials(), &tpop.pop) + names, err := t.Kernel().VFS().ListxattrAt(t, t.Credentials(), &tpop.pop, uint64(size)) if err != nil { return 0, nil, err } @@ -74,7 +74,7 @@ func Flistxattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sy } defer file.DecRef() - names, err := file.Listxattr(t) + names, err := file.Listxattr(t, uint64(size)) if err != nil { return 0, nil, err } @@ -116,7 +116,10 @@ func getxattr(t *kernel.Task, args arch.SyscallArguments, shouldFollowFinalSymli return 0, nil, err } - value, err := t.Kernel().VFS().GetxattrAt(t, t.Credentials(), &tpop.pop, name) + value, err := t.Kernel().VFS().GetxattrAt(t, t.Credentials(), &tpop.pop, &vfs.GetxattrOptions{ + Name: name, + Size: uint64(size), + }) if err != nil { return 0, nil, err } @@ -145,7 +148,7 @@ func Fgetxattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sys return 0, nil, err } - value, err := file.Getxattr(t, name) + value, err := file.Getxattr(t, &vfs.GetxattrOptions{Name: name, Size: uint64(size)}) if err != nil { return 0, nil, err } @@ -230,7 +233,7 @@ func Fsetxattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sys return 0, nil, err } - return 0, nil, file.Setxattr(t, vfs.SetxattrOptions{ + return 0, nil, file.Setxattr(t, &vfs.SetxattrOptions{ Name: name, Value: value, Flags: uint32(flags), diff --git a/pkg/sentry/vfs/anonfs.go b/pkg/sentry/vfs/anonfs.go index d1f6dfb45..a64d86122 100644 --- a/pkg/sentry/vfs/anonfs.go +++ b/pkg/sentry/vfs/anonfs.go @@ -245,7 +245,7 @@ func (fs *anonFilesystem) BoundEndpointAt(ctx context.Context, rp *ResolvingPath } // ListxattrAt implements FilesystemImpl.ListxattrAt. -func (fs *anonFilesystem) ListxattrAt(ctx context.Context, rp *ResolvingPath) ([]string, error) { +func (fs *anonFilesystem) ListxattrAt(ctx context.Context, rp *ResolvingPath, size uint64) ([]string, error) { if !rp.Done() { return nil, syserror.ENOTDIR } @@ -253,7 +253,7 @@ func (fs *anonFilesystem) ListxattrAt(ctx context.Context, rp *ResolvingPath) ([ } // GetxattrAt implements FilesystemImpl.GetxattrAt. -func (fs *anonFilesystem) GetxattrAt(ctx context.Context, rp *ResolvingPath, name string) (string, error) { +func (fs *anonFilesystem) GetxattrAt(ctx context.Context, rp *ResolvingPath, opts GetxattrOptions) (string, error) { if !rp.Done() { return "", syserror.ENOTDIR } diff --git a/pkg/sentry/vfs/file_description.go b/pkg/sentry/vfs/file_description.go index 20c545fca..4fb9aea87 100644 --- a/pkg/sentry/vfs/file_description.go +++ b/pkg/sentry/vfs/file_description.go @@ -401,11 +401,11 @@ type FileDescriptionImpl interface { Ioctl(ctx context.Context, uio usermem.IO, args arch.SyscallArguments) (uintptr, error) // Listxattr returns all extended attribute names for the file. - Listxattr(ctx context.Context) ([]string, error) + Listxattr(ctx context.Context, size uint64) ([]string, error) // Getxattr returns the value associated with the given extended attribute // for the file. - Getxattr(ctx context.Context, name string) (string, error) + Getxattr(ctx context.Context, opts GetxattrOptions) (string, error) // Setxattr changes the value associated with the given extended attribute // for the file. @@ -605,18 +605,23 @@ func (fd *FileDescription) Ioctl(ctx context.Context, uio usermem.IO, args arch. // Listxattr returns all extended attribute names for the file represented by // fd. -func (fd *FileDescription) Listxattr(ctx context.Context) ([]string, error) { +// +// If the size of the list (including a NUL terminating byte after every entry) +// would exceed size, ERANGE may be returned. Note that implementations +// are free to ignore size entirely and return without error). In all cases, +// if size is 0, the list should be returned without error, regardless of size. +func (fd *FileDescription) Listxattr(ctx context.Context, size uint64) ([]string, error) { if fd.opts.UseDentryMetadata { vfsObj := fd.vd.mount.vfs rp := vfsObj.getResolvingPath(auth.CredentialsFromContext(ctx), &PathOperation{ Root: fd.vd, Start: fd.vd, }) - names, err := fd.vd.mount.fs.impl.ListxattrAt(ctx, rp) + names, err := fd.vd.mount.fs.impl.ListxattrAt(ctx, rp, size) vfsObj.putResolvingPath(rp) return names, err } - names, err := fd.impl.Listxattr(ctx) + names, err := fd.impl.Listxattr(ctx, size) if err == syserror.ENOTSUP { // Linux doesn't actually return ENOTSUP in this case; instead, // fs/xattr.c:vfs_listxattr() falls back to allowing the security @@ -629,34 +634,39 @@ func (fd *FileDescription) Listxattr(ctx context.Context) ([]string, error) { // Getxattr returns the value associated with the given extended attribute for // the file represented by fd. -func (fd *FileDescription) Getxattr(ctx context.Context, name string) (string, error) { +// +// If the size of the return value exceeds opts.Size, ERANGE may be returned +// (note that implementations are free to ignore opts.Size entirely and return +// without error). In all cases, if opts.Size is 0, the value should be +// returned without error, regardless of size. +func (fd *FileDescription) Getxattr(ctx context.Context, opts *GetxattrOptions) (string, error) { if fd.opts.UseDentryMetadata { vfsObj := fd.vd.mount.vfs rp := vfsObj.getResolvingPath(auth.CredentialsFromContext(ctx), &PathOperation{ Root: fd.vd, Start: fd.vd, }) - val, err := fd.vd.mount.fs.impl.GetxattrAt(ctx, rp, name) + val, err := fd.vd.mount.fs.impl.GetxattrAt(ctx, rp, *opts) vfsObj.putResolvingPath(rp) return val, err } - return fd.impl.Getxattr(ctx, name) + return fd.impl.Getxattr(ctx, *opts) } // Setxattr changes the value associated with the given extended attribute for // the file represented by fd. -func (fd *FileDescription) Setxattr(ctx context.Context, opts SetxattrOptions) error { +func (fd *FileDescription) Setxattr(ctx context.Context, opts *SetxattrOptions) error { if fd.opts.UseDentryMetadata { vfsObj := fd.vd.mount.vfs rp := vfsObj.getResolvingPath(auth.CredentialsFromContext(ctx), &PathOperation{ Root: fd.vd, Start: fd.vd, }) - err := fd.vd.mount.fs.impl.SetxattrAt(ctx, rp, opts) + err := fd.vd.mount.fs.impl.SetxattrAt(ctx, rp, *opts) vfsObj.putResolvingPath(rp) return err } - return fd.impl.Setxattr(ctx, opts) + return fd.impl.Setxattr(ctx, *opts) } // Removexattr removes the given extended attribute from the file represented diff --git a/pkg/sentry/vfs/file_description_impl_util.go b/pkg/sentry/vfs/file_description_impl_util.go index d45e602ce..f4c111926 100644 --- a/pkg/sentry/vfs/file_description_impl_util.go +++ b/pkg/sentry/vfs/file_description_impl_util.go @@ -130,14 +130,14 @@ func (FileDescriptionDefaultImpl) Ioctl(ctx context.Context, uio usermem.IO, arg // Listxattr implements FileDescriptionImpl.Listxattr analogously to // inode_operations::listxattr == NULL in Linux. -func (FileDescriptionDefaultImpl) Listxattr(ctx context.Context) ([]string, error) { +func (FileDescriptionDefaultImpl) Listxattr(ctx context.Context, size uint64) ([]string, error) { // This isn't exactly accurate; see FileDescription.Listxattr. return nil, syserror.ENOTSUP } // Getxattr implements FileDescriptionImpl.Getxattr analogously to // inode::i_opflags & IOP_XATTR == 0 in Linux. -func (FileDescriptionDefaultImpl) Getxattr(ctx context.Context, name string) (string, error) { +func (FileDescriptionDefaultImpl) Getxattr(ctx context.Context, opts GetxattrOptions) (string, error) { return "", syserror.ENOTSUP } diff --git a/pkg/sentry/vfs/filesystem.go b/pkg/sentry/vfs/filesystem.go index bef1bd312..a537a29d1 100644 --- a/pkg/sentry/vfs/filesystem.go +++ b/pkg/sentry/vfs/filesystem.go @@ -442,7 +442,13 @@ type FilesystemImpl interface { // - If extended attributes are not supported by the filesystem, // ListxattrAt returns nil. (See FileDescription.Listxattr for an // explanation.) - ListxattrAt(ctx context.Context, rp *ResolvingPath) ([]string, error) + // + // - If the size of the list (including a NUL terminating byte after every + // entry) would exceed size, ERANGE may be returned. Note that + // implementations are free to ignore size entirely and return without + // error). In all cases, if size is 0, the list should be returned without + // error, regardless of size. + ListxattrAt(ctx context.Context, rp *ResolvingPath, size uint64) ([]string, error) // GetxattrAt returns the value associated with the given extended // attribute for the file at rp. @@ -451,7 +457,15 @@ type FilesystemImpl interface { // // - If extended attributes are not supported by the filesystem, GetxattrAt // returns ENOTSUP. - GetxattrAt(ctx context.Context, rp *ResolvingPath, name string) (string, error) + // + // - If an extended attribute named opts.Name does not exist, ENODATA is + // returned. + // + // - If the size of the return value exceeds opts.Size, ERANGE may be + // returned (note that implementations are free to ignore opts.Size entirely + // and return without error). In all cases, if opts.Size is 0, the value + // should be returned without error, regardless of size. + GetxattrAt(ctx context.Context, rp *ResolvingPath, opts GetxattrOptions) (string, error) // SetxattrAt changes the value associated with the given extended // attribute for the file at rp. @@ -460,6 +474,10 @@ type FilesystemImpl interface { // // - If extended attributes are not supported by the filesystem, SetxattrAt // returns ENOTSUP. + // + // - If XATTR_CREATE is set in opts.Flag and opts.Name already exists, + // EEXIST is returned. If XATTR_REPLACE is set and opts.Name does not exist, + // ENODATA is returned. SetxattrAt(ctx context.Context, rp *ResolvingPath, opts SetxattrOptions) error // RemovexattrAt removes the given extended attribute from the file at rp. @@ -468,6 +486,8 @@ type FilesystemImpl interface { // // - If extended attributes are not supported by the filesystem, // RemovexattrAt returns ENOTSUP. + // + // - If name does not exist, ENODATA is returned. RemovexattrAt(ctx context.Context, rp *ResolvingPath, name string) error // BoundEndpointAt returns the Unix socket endpoint bound at the path rp. diff --git a/pkg/sentry/vfs/memxattr/BUILD b/pkg/sentry/vfs/memxattr/BUILD new file mode 100644 index 000000000..d8c4d27b9 --- /dev/null +++ b/pkg/sentry/vfs/memxattr/BUILD @@ -0,0 +1,15 @@ +load("//tools:defs.bzl", "go_library") + +package(licenses = ["notice"]) + +go_library( + name = "memxattr", + srcs = ["xattr.go"], + visibility = ["//pkg/sentry:internal"], + deps = [ + "//pkg/abi/linux", + "//pkg/sentry/vfs", + "//pkg/sync", + "//pkg/syserror", + ], +) diff --git a/pkg/sentry/vfs/memxattr/xattr.go b/pkg/sentry/vfs/memxattr/xattr.go new file mode 100644 index 000000000..cc1e7d764 --- /dev/null +++ b/pkg/sentry/vfs/memxattr/xattr.go @@ -0,0 +1,102 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// Package memxattr provides a default, in-memory extended attribute +// implementation. +package memxattr + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sync" + "gvisor.dev/gvisor/pkg/syserror" +) + +// SimpleExtendedAttributes implements extended attributes using a map of +// names to values. +// +// +stateify savable +type SimpleExtendedAttributes struct { + // mu protects the below fields. + mu sync.RWMutex `state:"nosave"` + xattrs map[string]string +} + +// Getxattr returns the value at 'name'. +func (x *SimpleExtendedAttributes) Getxattr(opts *vfs.GetxattrOptions) (string, error) { + x.mu.RLock() + value, ok := x.xattrs[opts.Name] + x.mu.RUnlock() + if !ok { + return "", syserror.ENODATA + } + // Check that the size of the buffer provided in getxattr(2) is large enough + // to contain the value. + if opts.Size != 0 && uint64(len(value)) > opts.Size { + return "", syserror.ERANGE + } + return value, nil +} + +// Setxattr sets 'value' at 'name'. +func (x *SimpleExtendedAttributes) Setxattr(opts *vfs.SetxattrOptions) error { + x.mu.Lock() + defer x.mu.Unlock() + if x.xattrs == nil { + if opts.Flags&linux.XATTR_REPLACE != 0 { + return syserror.ENODATA + } + x.xattrs = make(map[string]string) + } + + _, ok := x.xattrs[opts.Name] + if ok && opts.Flags&linux.XATTR_CREATE != 0 { + return syserror.EEXIST + } + if !ok && opts.Flags&linux.XATTR_REPLACE != 0 { + return syserror.ENODATA + } + + x.xattrs[opts.Name] = opts.Value + return nil +} + +// Listxattr returns all names in xattrs. +func (x *SimpleExtendedAttributes) Listxattr(size uint64) ([]string, error) { + // Keep track of the size of the buffer needed in listxattr(2) for the list. + listSize := 0 + x.mu.RLock() + names := make([]string, 0, len(x.xattrs)) + for n := range x.xattrs { + names = append(names, n) + // Add one byte per null terminator. + listSize += len(n) + 1 + } + x.mu.RUnlock() + if size != 0 && uint64(listSize) > size { + return nil, syserror.ERANGE + } + return names, nil +} + +// Removexattr removes the xattr at 'name'. +func (x *SimpleExtendedAttributes) Removexattr(name string) error { + x.mu.Lock() + defer x.mu.Unlock() + if _, ok := x.xattrs[name]; !ok { + return syserror.ENODATA + } + delete(x.xattrs, name) + return nil +} diff --git a/pkg/sentry/vfs/options.go b/pkg/sentry/vfs/options.go index 2f04bf882..534528ce6 100644 --- a/pkg/sentry/vfs/options.go +++ b/pkg/sentry/vfs/options.go @@ -132,6 +132,20 @@ type SetStatOptions struct { Stat linux.Statx } +// GetxattrOptions contains options to VirtualFilesystem.GetxattrAt(), +// FilesystemImpl.GetxattrAt(), FileDescription.Getxattr(), and +// FileDescriptionImpl.Getxattr(). +type GetxattrOptions struct { + // Name is the name of the extended attribute to retrieve. + Name string + + // Size is the maximum value size that the caller will tolerate. If the value + // is larger than size, getxattr methods may return ERANGE, but they are also + // free to ignore the hint entirely (i.e. the value returned may be larger + // than size). All size checking is done independently at the syscall layer. + Size uint64 +} + // SetxattrOptions contains options to VirtualFilesystem.SetxattrAt(), // FilesystemImpl.SetxattrAt(), FileDescription.Setxattr(), and // FileDescriptionImpl.Setxattr(). diff --git a/pkg/sentry/vfs/vfs.go b/pkg/sentry/vfs/vfs.go index 720b90d8f..f592913d5 100644 --- a/pkg/sentry/vfs/vfs.go +++ b/pkg/sentry/vfs/vfs.go @@ -680,10 +680,10 @@ func (vfs *VirtualFilesystem) UnlinkAt(ctx context.Context, creds *auth.Credenti // ListxattrAt returns all extended attribute names for the file at the given // path. -func (vfs *VirtualFilesystem) ListxattrAt(ctx context.Context, creds *auth.Credentials, pop *PathOperation) ([]string, error) { +func (vfs *VirtualFilesystem) ListxattrAt(ctx context.Context, creds *auth.Credentials, pop *PathOperation, size uint64) ([]string, error) { rp := vfs.getResolvingPath(creds, pop) for { - names, err := rp.mount.fs.impl.ListxattrAt(ctx, rp) + names, err := rp.mount.fs.impl.ListxattrAt(ctx, rp, size) if err == nil { vfs.putResolvingPath(rp) return names, nil @@ -705,10 +705,10 @@ func (vfs *VirtualFilesystem) ListxattrAt(ctx context.Context, creds *auth.Crede // GetxattrAt returns the value associated with the given extended attribute // for the file at the given path. -func (vfs *VirtualFilesystem) GetxattrAt(ctx context.Context, creds *auth.Credentials, pop *PathOperation, name string) (string, error) { +func (vfs *VirtualFilesystem) GetxattrAt(ctx context.Context, creds *auth.Credentials, pop *PathOperation, opts *GetxattrOptions) (string, error) { rp := vfs.getResolvingPath(creds, pop) for { - val, err := rp.mount.fs.impl.GetxattrAt(ctx, rp, name) + val, err := rp.mount.fs.impl.GetxattrAt(ctx, rp, *opts) if err == nil { vfs.putResolvingPath(rp) return val, nil diff --git a/test/syscalls/linux/xattr.cc b/test/syscalls/linux/xattr.cc index 8b00ef44c..3231732ec 100644 --- a/test/syscalls/linux/xattr.cc +++ b/test/syscalls/linux/xattr.cc @@ -41,12 +41,12 @@ class XattrTest : public FileTest {}; TEST_F(XattrTest, XattrNonexistentFile) { const char* path = "/does/not/exist"; - EXPECT_THAT(setxattr(path, nullptr, nullptr, 0, /*flags=*/0), - SyscallFailsWithErrno(ENOENT)); - EXPECT_THAT(getxattr(path, nullptr, nullptr, 0), + const char* name = "user.test"; + EXPECT_THAT(setxattr(path, name, nullptr, 0, /*flags=*/0), SyscallFailsWithErrno(ENOENT)); + EXPECT_THAT(getxattr(path, name, nullptr, 0), SyscallFailsWithErrno(ENOENT)); EXPECT_THAT(listxattr(path, nullptr, 0), SyscallFailsWithErrno(ENOENT)); - EXPECT_THAT(removexattr(path, nullptr), SyscallFailsWithErrno(ENOENT)); + EXPECT_THAT(removexattr(path, name), SyscallFailsWithErrno(ENOENT)); } TEST_F(XattrTest, XattrNullName) { -- cgit v1.2.3 From f03996c5e9803934226e4b3a10827501cb936ab9 Mon Sep 17 00:00:00 2001 From: Jamie Liu Date: Thu, 16 Apr 2020 19:26:02 -0700 Subject: Implement pipe(2) and pipe2(2) for VFS2. Updates #1035 PiperOrigin-RevId: 306968644 --- pkg/sentry/fsimpl/pipefs/BUILD | 20 +++ pkg/sentry/fsimpl/pipefs/pipefs.go | 148 +++++++++++++++++++ pkg/sentry/fsimpl/tmpfs/filesystem.go | 2 +- pkg/sentry/fsimpl/tmpfs/named_pipe.go | 23 +-- pkg/sentry/fsimpl/tmpfs/tmpfs.go | 2 +- pkg/sentry/kernel/BUILD | 1 + pkg/sentry/kernel/kernel.go | 30 +++- pkg/sentry/kernel/pipe/vfs.go | 162 ++++++++++++--------- pkg/sentry/syscalls/linux/sys_pipe.go | 14 +- pkg/sentry/syscalls/linux/vfs2/BUILD | 3 + pkg/sentry/syscalls/linux/vfs2/fd.go | 17 +++ .../syscalls/linux/vfs2/linux64_override_amd64.go | 4 +- pkg/sentry/syscalls/linux/vfs2/pipe.go | 63 ++++++++ pkg/sentry/syscalls/linux/vfs2/read_write.go | 8 +- pkg/sentry/vfs/vfs.go | 2 +- test/syscalls/linux/pipe.cc | 2 + 16 files changed, 389 insertions(+), 112 deletions(-) create mode 100644 pkg/sentry/fsimpl/pipefs/BUILD create mode 100644 pkg/sentry/fsimpl/pipefs/pipefs.go create mode 100644 pkg/sentry/syscalls/linux/vfs2/pipe.go (limited to 'pkg/sentry/fsimpl/tmpfs/filesystem.go') diff --git a/pkg/sentry/fsimpl/pipefs/BUILD b/pkg/sentry/fsimpl/pipefs/BUILD new file mode 100644 index 000000000..0d411606f --- /dev/null +++ b/pkg/sentry/fsimpl/pipefs/BUILD @@ -0,0 +1,20 @@ +load("//tools:defs.bzl", "go_library") + +licenses(["notice"]) + +go_library( + name = "pipefs", + srcs = ["pipefs.go"], + visibility = ["//pkg/sentry:internal"], + deps = [ + "//pkg/abi/linux", + "//pkg/context", + "//pkg/sentry/fsimpl/kernfs", + "//pkg/sentry/kernel/auth", + "//pkg/sentry/kernel/pipe", + "//pkg/sentry/kernel/time", + "//pkg/sentry/vfs", + "//pkg/syserror", + "//pkg/usermem", + ], +) diff --git a/pkg/sentry/fsimpl/pipefs/pipefs.go b/pkg/sentry/fsimpl/pipefs/pipefs.go new file mode 100644 index 000000000..faf3179bc --- /dev/null +++ b/pkg/sentry/fsimpl/pipefs/pipefs.go @@ -0,0 +1,148 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// Package pipefs provides the filesystem implementation backing +// Kernel.PipeMount. +package pipefs + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs" + "gvisor.dev/gvisor/pkg/sentry/kernel/auth" + "gvisor.dev/gvisor/pkg/sentry/kernel/pipe" + ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" +) + +type filesystemType struct{} + +// Name implements vfs.FilesystemType.Name. +func (filesystemType) Name() string { + return "pipefs" +} + +// GetFilesystem implements vfs.FilesystemType.GetFilesystem. +func (filesystemType) GetFilesystem(ctx context.Context, vfsObj *vfs.VirtualFilesystem, creds *auth.Credentials, source string, opts vfs.GetFilesystemOptions) (*vfs.Filesystem, *vfs.Dentry, error) { + panic("pipefs.filesystemType.GetFilesystem should never be called") +} + +// filesystem implements vfs.FilesystemImpl. +type filesystem struct { + kernfs.Filesystem + + // TODO(gvisor.dev/issue/1193): + // + // - kernfs does not provide a way to implement statfs, from which we + // should indicate PIPEFS_MAGIC. + // + // - kernfs does not provide a way to override names for + // vfs.FilesystemImpl.PrependPath(); pipefs inodes should use synthetic + // name fmt.Sprintf("pipe:[%d]", inode.ino). +} + +// NewFilesystem sets up and returns a new vfs.Filesystem implemented by +// pipefs. +func NewFilesystem(vfsObj *vfs.VirtualFilesystem) *vfs.Filesystem { + fs := &filesystem{} + fs.Init(vfsObj, filesystemType{}) + return fs.VFSFilesystem() +} + +// inode implements kernfs.Inode. +type inode struct { + kernfs.InodeNotDirectory + kernfs.InodeNotSymlink + kernfs.InodeNoopRefCount + + pipe *pipe.VFSPipe + + ino uint64 + uid auth.KUID + gid auth.KGID + // We use the creation timestamp for all of atime, mtime, and ctime. + ctime ktime.Time +} + +func newInode(ctx context.Context, fs *kernfs.Filesystem) *inode { + creds := auth.CredentialsFromContext(ctx) + return &inode{ + pipe: pipe.NewVFSPipe(false /* isNamed */, pipe.DefaultPipeSize, usermem.PageSize), + ino: fs.NextIno(), + uid: creds.EffectiveKUID, + gid: creds.EffectiveKGID, + ctime: ktime.NowFromContext(ctx), + } +} + +const pipeMode = 0600 | linux.S_IFIFO + +// CheckPermissions implements kernfs.Inode.CheckPermissions. +func (i *inode) CheckPermissions(ctx context.Context, creds *auth.Credentials, ats vfs.AccessTypes) error { + return vfs.GenericCheckPermissions(creds, ats, pipeMode, i.uid, i.gid) +} + +// Mode implements kernfs.Inode.Mode. +func (i *inode) Mode() linux.FileMode { + return pipeMode +} + +// Stat implements kernfs.Inode.Stat. +func (i *inode) Stat(vfsfs *vfs.Filesystem, opts vfs.StatOptions) (linux.Statx, error) { + ts := linux.NsecToStatxTimestamp(i.ctime.Nanoseconds()) + return linux.Statx{ + Mask: linux.STATX_TYPE | linux.STATX_MODE | linux.STATX_NLINK | linux.STATX_UID | linux.STATX_GID | linux.STATX_ATIME | linux.STATX_MTIME | linux.STATX_CTIME | linux.STATX_INO | linux.STATX_SIZE | linux.STATX_BLOCKS, + Blksize: usermem.PageSize, + Nlink: 1, + UID: uint32(i.uid), + GID: uint32(i.gid), + Mode: pipeMode, + Ino: i.ino, + Size: 0, + Blocks: 0, + Atime: ts, + Ctime: ts, + Mtime: ts, + // TODO(gvisor.dev/issue/1197): Device number. + }, nil +} + +// SetStat implements kernfs.Inode.SetStat. +func (i *inode) SetStat(ctx context.Context, vfsfs *vfs.Filesystem, creds *auth.Credentials, opts vfs.SetStatOptions) error { + if opts.Stat.Mask == 0 { + return nil + } + return syserror.EPERM +} + +// Open implements kernfs.Inode.Open. +func (i *inode) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) { + // FIXME(b/38173783): kernfs does not plumb Context here. + return i.pipe.Open(context.Background(), rp.Mount(), vfsd, opts.Flags) +} + +// NewConnectedPipeFDs returns a pair of FileDescriptions representing the read +// and write ends of a newly-created pipe, as for pipe(2) and pipe2(2). +// +// Preconditions: mnt.Filesystem() must have been returned by NewFilesystem(). +func NewConnectedPipeFDs(ctx context.Context, mnt *vfs.Mount, flags uint32) (*vfs.FileDescription, *vfs.FileDescription) { + fs := mnt.Filesystem().Impl().(*kernfs.Filesystem) + inode := newInode(ctx, fs) + var d kernfs.Dentry + d.Init(inode) + defer d.DecRef() + return inode.pipe.ReaderWriterPair(mnt, d.VFSDentry(), flags) +} diff --git a/pkg/sentry/fsimpl/tmpfs/filesystem.go b/pkg/sentry/fsimpl/tmpfs/filesystem.go index f4d50d64f..660f5a29b 100644 --- a/pkg/sentry/fsimpl/tmpfs/filesystem.go +++ b/pkg/sentry/fsimpl/tmpfs/filesystem.go @@ -392,7 +392,7 @@ func (d *dentry) open(ctx context.Context, rp *vfs.ResolvingPath, opts *vfs.Open // Can't open symlinks without O_PATH (which is unimplemented). return nil, syserror.ELOOP case *namedPipe: - return newNamedPipeFD(ctx, impl, rp, &d.vfsd, opts.Flags) + return impl.pipe.Open(ctx, rp.Mount(), &d.vfsd, opts.Flags) case *deviceFile: return rp.VirtualFilesystem().OpenDeviceSpecialFile(ctx, rp.Mount(), &d.vfsd, impl.kind, impl.major, impl.minor, opts) case *socketFile: diff --git a/pkg/sentry/fsimpl/tmpfs/named_pipe.go b/pkg/sentry/fsimpl/tmpfs/named_pipe.go index 2c5c739df..8d77b3fa8 100644 --- a/pkg/sentry/fsimpl/tmpfs/named_pipe.go +++ b/pkg/sentry/fsimpl/tmpfs/named_pipe.go @@ -16,10 +16,8 @@ package tmpfs import ( "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/kernel/pipe" - "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/usermem" ) @@ -33,27 +31,8 @@ type namedPipe struct { // * fs.mu must be locked. // * rp.Mount().CheckBeginWrite() has been called successfully. func (fs *filesystem) newNamedPipe(creds *auth.Credentials, mode linux.FileMode) *inode { - file := &namedPipe{pipe: pipe.NewVFSPipe(pipe.DefaultPipeSize, usermem.PageSize)} + file := &namedPipe{pipe: pipe.NewVFSPipe(true /* isNamed */, pipe.DefaultPipeSize, usermem.PageSize)} file.inode.init(file, fs, creds, linux.S_IFIFO|mode) file.inode.nlink = 1 // Only the parent has a link. return &file.inode } - -// namedPipeFD implements vfs.FileDescriptionImpl. Methods are implemented -// entirely via struct embedding. -type namedPipeFD struct { - fileDescription - - *pipe.VFSPipeFD -} - -func newNamedPipeFD(ctx context.Context, np *namedPipe, rp *vfs.ResolvingPath, vfsd *vfs.Dentry, flags uint32) (*vfs.FileDescription, error) { - var err error - var fd namedPipeFD - fd.VFSPipeFD, err = np.pipe.NewVFSPipeFD(ctx, vfsd, &fd.vfsfd, flags) - if err != nil { - return nil, err - } - fd.vfsfd.Init(&fd, flags, rp.Mount(), vfsd, &vfs.FileDescriptionOptions{}) - return &fd.vfsfd, nil -} diff --git a/pkg/sentry/fsimpl/tmpfs/tmpfs.go b/pkg/sentry/fsimpl/tmpfs/tmpfs.go index 9fa8637d5..a59b24d45 100644 --- a/pkg/sentry/fsimpl/tmpfs/tmpfs.go +++ b/pkg/sentry/fsimpl/tmpfs/tmpfs.go @@ -357,6 +357,7 @@ func (i *inode) setStat(ctx context.Context, creds *auth.Credentials, stat *linu return err } i.mu.Lock() + defer i.mu.Unlock() var ( needsMtimeBump bool needsCtimeBump bool @@ -427,7 +428,6 @@ func (i *inode) setStat(ctx context.Context, creds *auth.Credentials, stat *linu atomic.StoreInt64(&i.ctime, now) } - i.mu.Unlock() return nil } diff --git a/pkg/sentry/kernel/BUILD b/pkg/sentry/kernel/BUILD index e0ff58d8c..e47af66d6 100644 --- a/pkg/sentry/kernel/BUILD +++ b/pkg/sentry/kernel/BUILD @@ -170,6 +170,7 @@ go_library( "//pkg/sentry/fs/timerfd", "//pkg/sentry/fsbridge", "//pkg/sentry/fsimpl/kernfs", + "//pkg/sentry/fsimpl/pipefs", "//pkg/sentry/fsimpl/sockfs", "//pkg/sentry/hostcpu", "//pkg/sentry/inet", diff --git a/pkg/sentry/kernel/kernel.go b/pkg/sentry/kernel/kernel.go index de8a95854..fef60e636 100644 --- a/pkg/sentry/kernel/kernel.go +++ b/pkg/sentry/kernel/kernel.go @@ -50,6 +50,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/timerfd" "gvisor.dev/gvisor/pkg/sentry/fsbridge" + "gvisor.dev/gvisor/pkg/sentry/fsimpl/pipefs" "gvisor.dev/gvisor/pkg/sentry/fsimpl/sockfs" "gvisor.dev/gvisor/pkg/sentry/hostcpu" "gvisor.dev/gvisor/pkg/sentry/inet" @@ -254,6 +255,10 @@ type Kernel struct { // VFS keeps the filesystem state used across the kernel. vfs vfs.VirtualFilesystem + // pipeMount is the Mount used for pipes created by the pipe() and pipe2() + // syscalls (as opposed to named pipes created by mknod()). + pipeMount *vfs.Mount + // If set to true, report address space activation waits as if the task is in // external wait so that the watchdog doesn't report the task stuck. SleepForAddressSpaceActivation bool @@ -354,19 +359,29 @@ func (k *Kernel) Init(args InitKernelArgs) error { k.monotonicClock = &timekeeperClock{tk: args.Timekeeper, c: sentrytime.Monotonic} k.futexes = futex.NewManager() k.netlinkPorts = port.New() + if VFS2Enabled { if err := k.vfs.Init(); err != nil { return fmt.Errorf("failed to initialize VFS: %v", err) } - fs := sockfs.NewFilesystem(&k.vfs) - // NewDisconnectedMount will take an additional reference on fs. - defer fs.DecRef() - sm, err := k.vfs.NewDisconnectedMount(fs, nil, &vfs.MountOptions{}) + + pipeFilesystem := pipefs.NewFilesystem(&k.vfs) + defer pipeFilesystem.DecRef() + pipeMount, err := k.vfs.NewDisconnectedMount(pipeFilesystem, nil, &vfs.MountOptions{}) + if err != nil { + return fmt.Errorf("failed to create pipefs mount: %v", err) + } + k.pipeMount = pipeMount + + socketFilesystem := sockfs.NewFilesystem(&k.vfs) + defer socketFilesystem.DecRef() + socketMount, err := k.vfs.NewDisconnectedMount(socketFilesystem, nil, &vfs.MountOptions{}) if err != nil { return fmt.Errorf("failed to initialize socket mount: %v", err) } - k.socketMount = sm + k.socketMount = socketMount } + return nil } @@ -1613,3 +1628,8 @@ func (k *Kernel) EmitUnimplementedEvent(ctx context.Context) { func (k *Kernel) VFS() *vfs.VirtualFilesystem { return &k.vfs } + +// PipeMount returns the pipefs mount. +func (k *Kernel) PipeMount() *vfs.Mount { + return k.pipeMount +} diff --git a/pkg/sentry/kernel/pipe/vfs.go b/pkg/sentry/kernel/pipe/vfs.go index a5675bd70..b54f08a30 100644 --- a/pkg/sentry/kernel/pipe/vfs.go +++ b/pkg/sentry/kernel/pipe/vfs.go @@ -49,38 +49,42 @@ type VFSPipe struct { } // NewVFSPipe returns an initialized VFSPipe. -func NewVFSPipe(sizeBytes, atomicIOBytes int64) *VFSPipe { +func NewVFSPipe(isNamed bool, sizeBytes, atomicIOBytes int64) *VFSPipe { var vp VFSPipe - initPipe(&vp.pipe, true /* isNamed */, sizeBytes, atomicIOBytes) + initPipe(&vp.pipe, isNamed, sizeBytes, atomicIOBytes) return &vp } -// NewVFSPipeFD opens a named pipe. Named pipes have special blocking semantics -// during open: +// ReaderWriterPair returns read-only and write-only FDs for vp. // -// "Normally, opening the FIFO blocks until the other end is opened also. A -// process can open a FIFO in nonblocking mode. In this case, opening for -// read-only will succeed even if no-one has opened on the write side yet, -// opening for write-only will fail with ENXIO (no such device or address) -// unless the other end has already been opened. Under Linux, opening a FIFO -// for read and write will succeed both in blocking and nonblocking mode. POSIX -// leaves this behavior undefined. This can be used to open a FIFO for writing -// while there are no readers available." - fifo(7) -func (vp *VFSPipe) NewVFSPipeFD(ctx context.Context, vfsd *vfs.Dentry, vfsfd *vfs.FileDescription, flags uint32) (*VFSPipeFD, error) { +// Preconditions: statusFlags should not contain an open access mode. +func (vp *VFSPipe) ReaderWriterPair(mnt *vfs.Mount, vfsd *vfs.Dentry, statusFlags uint32) (*vfs.FileDescription, *vfs.FileDescription) { + return vp.newFD(mnt, vfsd, linux.O_RDONLY|statusFlags), vp.newFD(mnt, vfsd, linux.O_WRONLY|statusFlags) +} + +// Open opens the pipe represented by vp. +func (vp *VFSPipe) Open(ctx context.Context, mnt *vfs.Mount, vfsd *vfs.Dentry, statusFlags uint32) (*vfs.FileDescription, error) { vp.mu.Lock() defer vp.mu.Unlock() - readable := vfs.MayReadFileWithOpenFlags(flags) - writable := vfs.MayWriteFileWithOpenFlags(flags) + readable := vfs.MayReadFileWithOpenFlags(statusFlags) + writable := vfs.MayWriteFileWithOpenFlags(statusFlags) if !readable && !writable { return nil, syserror.EINVAL } - vfd, err := vp.open(vfsd, vfsfd, flags) - if err != nil { - return nil, err - } + fd := vp.newFD(mnt, vfsd, statusFlags) + // Named pipes have special blocking semantics during open: + // + // "Normally, opening the FIFO blocks until the other end is opened also. A + // process can open a FIFO in nonblocking mode. In this case, opening for + // read-only will succeed even if no-one has opened on the write side yet, + // opening for write-only will fail with ENXIO (no such device or address) + // unless the other end has already been opened. Under Linux, opening a + // FIFO for read and write will succeed both in blocking and nonblocking + // mode. POSIX leaves this behavior undefined. This can be used to open a + // FIFO for writing while there are no readers available." - fifo(7) switch { case readable && writable: // Pipes opened for read-write always succeed without blocking. @@ -89,23 +93,26 @@ func (vp *VFSPipe) NewVFSPipeFD(ctx context.Context, vfsd *vfs.Dentry, vfsfd *vf case readable: newHandleLocked(&vp.rWakeup) - // If this pipe is being opened as nonblocking and there's no + // If this pipe is being opened as blocking and there's no // writer, we have to wait for a writer to open the other end. - if flags&linux.O_NONBLOCK == 0 && !vp.pipe.HasWriters() && !waitFor(&vp.mu, &vp.wWakeup, ctx) { + if vp.pipe.isNamed && statusFlags&linux.O_NONBLOCK == 0 && !vp.pipe.HasWriters() && !waitFor(&vp.mu, &vp.wWakeup, ctx) { + fd.DecRef() return nil, syserror.EINTR } case writable: newHandleLocked(&vp.wWakeup) - if !vp.pipe.HasReaders() { - // Nonblocking, write-only opens fail with ENXIO when - // the read side isn't open yet. - if flags&linux.O_NONBLOCK != 0 { + if vp.pipe.isNamed && !vp.pipe.HasReaders() { + // Non-blocking, write-only opens fail with ENXIO when the read + // side isn't open yet. + if statusFlags&linux.O_NONBLOCK != 0 { + fd.DecRef() return nil, syserror.ENXIO } // Wait for a reader to open the other end. if !waitFor(&vp.mu, &vp.rWakeup, ctx) { + fd.DecRef() return nil, syserror.EINTR } } @@ -114,96 +121,93 @@ func (vp *VFSPipe) NewVFSPipeFD(ctx context.Context, vfsd *vfs.Dentry, vfsfd *vf panic("invalid pipe flags: must be readable, writable, or both") } - return vfd, nil + return fd, nil } // Preconditions: vp.mu must be held. -func (vp *VFSPipe) open(vfsd *vfs.Dentry, vfsfd *vfs.FileDescription, flags uint32) (*VFSPipeFD, error) { - var fd VFSPipeFD - fd.flags = flags - fd.readable = vfs.MayReadFileWithOpenFlags(flags) - fd.writable = vfs.MayWriteFileWithOpenFlags(flags) - fd.vfsfd = vfsfd - fd.pipe = &vp.pipe +func (vp *VFSPipe) newFD(mnt *vfs.Mount, vfsd *vfs.Dentry, statusFlags uint32) *vfs.FileDescription { + fd := &VFSPipeFD{ + pipe: &vp.pipe, + } + fd.vfsfd.Init(fd, statusFlags, mnt, vfsd, &vfs.FileDescriptionOptions{ + DenyPRead: true, + DenyPWrite: true, + UseDentryMetadata: true, + }) switch { - case fd.readable && fd.writable: + case fd.vfsfd.IsReadable() && fd.vfsfd.IsWritable(): vp.pipe.rOpen() vp.pipe.wOpen() - case fd.readable: + case fd.vfsfd.IsReadable(): vp.pipe.rOpen() - case fd.writable: + case fd.vfsfd.IsWritable(): vp.pipe.wOpen() default: panic("invalid pipe flags: must be readable, writable, or both") } - return &fd, nil + return &fd.vfsfd } -// VFSPipeFD implements a subset of vfs.FileDescriptionImpl for pipes. It is -// expected that filesystesm will use this in a struct implementing -// vfs.FileDescriptionImpl. +// VFSPipeFD implements vfs.FileDescriptionImpl for pipes. type VFSPipeFD struct { - pipe *Pipe - flags uint32 - readable bool - writable bool - vfsfd *vfs.FileDescription + vfsfd vfs.FileDescription + vfs.FileDescriptionDefaultImpl + vfs.DentryMetadataFileDescriptionImpl + + pipe *Pipe } // Release implements vfs.FileDescriptionImpl.Release. func (fd *VFSPipeFD) Release() { var event waiter.EventMask - if fd.readable { + if fd.vfsfd.IsReadable() { fd.pipe.rClose() - event |= waiter.EventIn + event |= waiter.EventOut } - if fd.writable { + if fd.vfsfd.IsWritable() { fd.pipe.wClose() - event |= waiter.EventOut + event |= waiter.EventIn | waiter.EventHUp } if event == 0 { panic("invalid pipe flags: must be readable, writable, or both") } - if fd.writable { - fd.vfsfd.VirtualDentry().Mount().EndWrite() - } - fd.pipe.Notify(event) } -// OnClose implements vfs.FileDescriptionImpl.OnClose. -func (fd *VFSPipeFD) OnClose(_ context.Context) error { - return nil +// Readiness implements waiter.Waitable.Readiness. +func (fd *VFSPipeFD) Readiness(mask waiter.EventMask) waiter.EventMask { + switch { + case fd.vfsfd.IsReadable() && fd.vfsfd.IsWritable(): + return fd.pipe.rwReadiness() + case fd.vfsfd.IsReadable(): + return fd.pipe.rReadiness() + case fd.vfsfd.IsWritable(): + return fd.pipe.wReadiness() + default: + panic("pipe FD is neither readable nor writable") + } } -// PRead implements vfs.FileDescriptionImpl.PRead. -func (fd *VFSPipeFD) PRead(_ context.Context, _ usermem.IOSequence, _ int64, _ vfs.ReadOptions) (int64, error) { - return 0, syserror.ESPIPE +// EventRegister implements waiter.Waitable.EventRegister. +func (fd *VFSPipeFD) EventRegister(e *waiter.Entry, mask waiter.EventMask) { + fd.pipe.EventRegister(e, mask) +} + +// EventUnregister implements waiter.Waitable.EventUnregister. +func (fd *VFSPipeFD) EventUnregister(e *waiter.Entry) { + fd.pipe.EventUnregister(e) } // Read implements vfs.FileDescriptionImpl.Read. func (fd *VFSPipeFD) Read(ctx context.Context, dst usermem.IOSequence, _ vfs.ReadOptions) (int64, error) { - if !fd.readable { - return 0, syserror.EINVAL - } - return fd.pipe.Read(ctx, dst) } -// PWrite implements vfs.FileDescriptionImpl.PWrite. -func (fd *VFSPipeFD) PWrite(_ context.Context, _ usermem.IOSequence, _ int64, _ vfs.WriteOptions) (int64, error) { - return 0, syserror.ESPIPE -} - // Write implements vfs.FileDescriptionImpl.Write. func (fd *VFSPipeFD) Write(ctx context.Context, src usermem.IOSequence, _ vfs.WriteOptions) (int64, error) { - if !fd.writable { - return 0, syserror.EINVAL - } - return fd.pipe.Write(ctx, src) } @@ -211,3 +215,17 @@ func (fd *VFSPipeFD) Write(ctx context.Context, src usermem.IOSequence, _ vfs.Wr func (fd *VFSPipeFD) Ioctl(ctx context.Context, uio usermem.IO, args arch.SyscallArguments) (uintptr, error) { return fd.pipe.Ioctl(ctx, uio, args) } + +// PipeSize implements fcntl(F_GETPIPE_SZ). +func (fd *VFSPipeFD) PipeSize() int64 { + // Inline Pipe.FifoSize() rather than calling it with nil Context and + // fs.File and ignoring the returned error (which is always nil). + fd.pipe.mu.Lock() + defer fd.pipe.mu.Unlock() + return fd.pipe.max +} + +// SetPipeSize implements fcntl(F_SETPIPE_SZ). +func (fd *VFSPipeFD) SetPipeSize(size int64) (int64, error) { + return fd.pipe.SetFifoSize(size) +} diff --git a/pkg/sentry/syscalls/linux/sys_pipe.go b/pkg/sentry/syscalls/linux/sys_pipe.go index 798344042..43c510930 100644 --- a/pkg/sentry/syscalls/linux/sys_pipe.go +++ b/pkg/sentry/syscalls/linux/sys_pipe.go @@ -24,6 +24,8 @@ import ( "gvisor.dev/gvisor/pkg/usermem" ) +// LINT.IfChange + // pipe2 implements the actual system call with flags. func pipe2(t *kernel.Task, addr usermem.Addr, flags uint) (uintptr, error) { if flags&^(linux.O_NONBLOCK|linux.O_CLOEXEC) != 0 { @@ -45,10 +47,12 @@ func pipe2(t *kernel.Task, addr usermem.Addr, flags uint) (uintptr, error) { } if _, err := t.CopyOut(addr, fds); err != nil { - // The files are not closed in this case, the exact semantics - // of this error case are not well defined, but they could have - // already been observed by user space. - return 0, syserror.EFAULT + for _, fd := range fds { + if file, _ := t.FDTable().Remove(fd); file != nil { + file.DecRef() + } + } + return 0, err } return 0, nil } @@ -69,3 +73,5 @@ func Pipe2(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall n, err := pipe2(t, addr, flags) return n, nil, err } + +// LINT.ThenChange(vfs2/pipe.go) diff --git a/pkg/sentry/syscalls/linux/vfs2/BUILD b/pkg/sentry/syscalls/linux/vfs2/BUILD index b32abfe59..6ff2d84d2 100644 --- a/pkg/sentry/syscalls/linux/vfs2/BUILD +++ b/pkg/sentry/syscalls/linux/vfs2/BUILD @@ -18,6 +18,7 @@ go_library( "linux64_override_arm64.go", "mmap.go", "path.go", + "pipe.go", "poll.go", "read_write.go", "setstat.go", @@ -39,8 +40,10 @@ go_library( "//pkg/gohacks", "//pkg/sentry/arch", "//pkg/sentry/fsbridge", + "//pkg/sentry/fsimpl/pipefs", "//pkg/sentry/kernel", "//pkg/sentry/kernel/auth", + "//pkg/sentry/kernel/pipe", "//pkg/sentry/kernel/time", "//pkg/sentry/limits", "//pkg/sentry/loader", diff --git a/pkg/sentry/syscalls/linux/vfs2/fd.go b/pkg/sentry/syscalls/linux/vfs2/fd.go index 3afcea665..8181d80f4 100644 --- a/pkg/sentry/syscalls/linux/vfs2/fd.go +++ b/pkg/sentry/syscalls/linux/vfs2/fd.go @@ -18,6 +18,7 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/sentry/kernel/pipe" slinux "gvisor.dev/gvisor/pkg/sentry/syscalls/linux" "gvisor.dev/gvisor/pkg/syserror" ) @@ -140,6 +141,22 @@ func Fcntl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall return uintptr(file.StatusFlags()), nil, nil case linux.F_SETFL: return 0, nil, file.SetStatusFlags(t, t.Credentials(), args[2].Uint()) + case linux.F_SETPIPE_SZ: + pipefile, ok := file.Impl().(*pipe.VFSPipeFD) + if !ok { + return 0, nil, syserror.EBADF + } + n, err := pipefile.SetPipeSize(int64(args[2].Int())) + if err != nil { + return 0, nil, err + } + return uintptr(n), nil, nil + case linux.F_GETPIPE_SZ: + pipefile, ok := file.Impl().(*pipe.VFSPipeFD) + if !ok { + return 0, nil, syserror.EBADF + } + return uintptr(pipefile.PipeSize()), nil, nil default: // TODO(gvisor.dev/issue/1623): Everything else is not yet supported. return 0, nil, syserror.EINVAL diff --git a/pkg/sentry/syscalls/linux/vfs2/linux64_override_amd64.go b/pkg/sentry/syscalls/linux/vfs2/linux64_override_amd64.go index 645e0bcb8..21eb98444 100644 --- a/pkg/sentry/syscalls/linux/vfs2/linux64_override_amd64.go +++ b/pkg/sentry/syscalls/linux/vfs2/linux64_override_amd64.go @@ -39,7 +39,7 @@ func Override(table map[uintptr]kernel.Syscall) { table[19] = syscalls.Supported("readv", Readv) table[20] = syscalls.Supported("writev", Writev) table[21] = syscalls.Supported("access", Access) - delete(table, 22) // pipe + table[22] = syscalls.Supported("pipe", Pipe) table[23] = syscalls.Supported("select", Select) table[32] = syscalls.Supported("dup", Dup) table[33] = syscalls.Supported("dup2", Dup2) @@ -151,7 +151,7 @@ func Override(table map[uintptr]kernel.Syscall) { delete(table, 290) // eventfd2 table[291] = syscalls.Supported("epoll_create1", EpollCreate1) table[292] = syscalls.Supported("dup3", Dup3) - delete(table, 293) // pipe2 + table[293] = syscalls.Supported("pipe2", Pipe2) delete(table, 294) // inotify_init1 table[295] = syscalls.Supported("preadv", Preadv) table[296] = syscalls.Supported("pwritev", Pwritev) diff --git a/pkg/sentry/syscalls/linux/vfs2/pipe.go b/pkg/sentry/syscalls/linux/vfs2/pipe.go new file mode 100644 index 000000000..4a01e4209 --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/pipe.go @@ -0,0 +1,63 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/fsimpl/pipefs" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" +) + +// Pipe implements Linux syscall pipe(2). +func Pipe(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + addr := args[0].Pointer() + return 0, nil, pipe2(t, addr, 0) +} + +// Pipe2 implements Linux syscall pipe2(2). +func Pipe2(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + addr := args[0].Pointer() + flags := args[1].Int() + return 0, nil, pipe2(t, addr, flags) +} + +func pipe2(t *kernel.Task, addr usermem.Addr, flags int32) error { + if flags&^(linux.O_NONBLOCK|linux.O_CLOEXEC) != 0 { + return syserror.EINVAL + } + r, w := pipefs.NewConnectedPipeFDs(t, t.Kernel().PipeMount(), uint32(flags&linux.O_NONBLOCK)) + defer r.DecRef() + defer w.DecRef() + + fds, err := t.NewFDsVFS2(0, []*vfs.FileDescription{r, w}, kernel.FDFlags{ + CloseOnExec: flags&linux.O_CLOEXEC != 0, + }) + if err != nil { + return err + } + if _, err := t.CopyOut(addr, fds); err != nil { + for _, fd := range fds { + if _, file := t.FDTable().Remove(fd); file != nil { + file.DecRef() + } + } + return err + } + return nil +} diff --git a/pkg/sentry/syscalls/linux/vfs2/read_write.go b/pkg/sentry/syscalls/linux/vfs2/read_write.go index 898b190fd..6c6998f45 100644 --- a/pkg/sentry/syscalls/linux/vfs2/read_write.go +++ b/pkg/sentry/syscalls/linux/vfs2/read_write.go @@ -103,7 +103,7 @@ func read(t *kernel.Task, file *vfs.FileDescription, dst usermem.IOSequence, opt // Issue the request and break out if it completes with anything other than // "would block". - n, err := file.Read(t, dst, opts) + n, err = file.Read(t, dst, opts) total += n if err != syserror.ErrWouldBlock { break @@ -248,7 +248,7 @@ func pread(t *kernel.Task, file *vfs.FileDescription, dst usermem.IOSequence, of // Issue the request and break out if it completes with anything other than // "would block". - n, err := file.PRead(t, dst, offset+total, opts) + n, err = file.PRead(t, dst, offset+total, opts) total += n if err != syserror.ErrWouldBlock { break @@ -335,7 +335,7 @@ func write(t *kernel.Task, file *vfs.FileDescription, src usermem.IOSequence, op // Issue the request and break out if it completes with anything other than // "would block". - n, err := file.Write(t, src, opts) + n, err = file.Write(t, src, opts) total += n if err != syserror.ErrWouldBlock { break @@ -480,7 +480,7 @@ func pwrite(t *kernel.Task, file *vfs.FileDescription, src usermem.IOSequence, o // Issue the request and break out if it completes with anything other than // "would block". - n, err := file.PWrite(t, src, offset+total, opts) + n, err = file.PWrite(t, src, offset+total, opts) total += n if err != syserror.ErrWouldBlock { break diff --git a/pkg/sentry/vfs/vfs.go b/pkg/sentry/vfs/vfs.go index 053c6e1d1..cb5bbd781 100644 --- a/pkg/sentry/vfs/vfs.go +++ b/pkg/sentry/vfs/vfs.go @@ -335,7 +335,7 @@ func (vfs *VirtualFilesystem) MknodAt(ctx context.Context, creds *auth.Credentia rp := vfs.getResolvingPath(creds, pop) for { err := rp.mount.fs.impl.MknodAt(ctx, rp, *opts) - if err != nil { + if err == nil { vfs.putResolvingPath(rp) return nil } diff --git a/test/syscalls/linux/pipe.cc b/test/syscalls/linux/pipe.cc index d8e19e910..67228b66b 100644 --- a/test/syscalls/linux/pipe.cc +++ b/test/syscalls/linux/pipe.cc @@ -265,6 +265,8 @@ TEST_P(PipeTest, OffsetCalls) { SyscallFailsWithErrno(ESPIPE)); struct iovec iov; + iov.iov_base = &buf; + iov.iov_len = sizeof(buf); EXPECT_THAT(preadv(wfd_.get(), &iov, 1, 0), SyscallFailsWithErrno(ESPIPE)); EXPECT_THAT(pwritev(rfd_.get(), &iov, 1, 0), SyscallFailsWithErrno(ESPIPE)); } -- cgit v1.2.3 From e72ce8cce46ed48af306df50d252853c8790924d Mon Sep 17 00:00:00 2001 From: Jamie Liu Date: Mon, 20 Apr 2020 10:09:23 -0700 Subject: Change lingering uses of "memfs" in fsimpl/tmpfs to "tmpfs". PiperOrigin-RevId: 307422746 --- pkg/sentry/fsimpl/tmpfs/benchmark_test.go | 4 ++-- pkg/sentry/fsimpl/tmpfs/filesystem.go | 2 +- pkg/sentry/fsimpl/tmpfs/tmpfs.go | 2 +- 3 files changed, 4 insertions(+), 4 deletions(-) (limited to 'pkg/sentry/fsimpl/tmpfs/filesystem.go') diff --git a/pkg/sentry/fsimpl/tmpfs/benchmark_test.go b/pkg/sentry/fsimpl/tmpfs/benchmark_test.go index 383133e44..651912169 100644 --- a/pkg/sentry/fsimpl/tmpfs/benchmark_test.go +++ b/pkg/sentry/fsimpl/tmpfs/benchmark_test.go @@ -168,7 +168,7 @@ func BenchmarkVFS1TmpfsStat(b *testing.B) { } } -func BenchmarkVFS2MemfsStat(b *testing.B) { +func BenchmarkVFS2TmpfsStat(b *testing.B) { for _, depth := range depths { b.Run(fmt.Sprintf("%d", depth), func(b *testing.B) { ctx := contexttest.Context(b) @@ -362,7 +362,7 @@ func BenchmarkVFS1TmpfsMountStat(b *testing.B) { } } -func BenchmarkVFS2MemfsMountStat(b *testing.B) { +func BenchmarkVFS2TmpfsMountStat(b *testing.B) { for _, depth := range depths { b.Run(fmt.Sprintf("%d", depth), func(b *testing.B) { ctx := contexttest.Context(b) diff --git a/pkg/sentry/fsimpl/tmpfs/filesystem.go b/pkg/sentry/fsimpl/tmpfs/filesystem.go index 660f5a29b..452c4e2e0 100644 --- a/pkg/sentry/fsimpl/tmpfs/filesystem.go +++ b/pkg/sentry/fsimpl/tmpfs/filesystem.go @@ -148,7 +148,7 @@ func (fs *filesystem) doCreateAt(rp *vfs.ResolvingPath, dir bool, create func(pa if !dir && rp.MustBeDir() { return syserror.ENOENT } - // In memfs, the only way to cause a dentry to be disowned is by removing + // In tmpfs, the only way to cause a dentry to be disowned is by removing // it from the filesystem, so this check is equivalent to checking if // parent has been removed. if parent.vfsd.IsDisowned() { diff --git a/pkg/sentry/fsimpl/tmpfs/tmpfs.go b/pkg/sentry/fsimpl/tmpfs/tmpfs.go index a59b24d45..82c709b43 100644 --- a/pkg/sentry/fsimpl/tmpfs/tmpfs.go +++ b/pkg/sentry/fsimpl/tmpfs/tmpfs.go @@ -247,7 +247,7 @@ func (i *inode) incLinksLocked() { panic("tmpfs.inode.incLinksLocked() called with no existing links") } if i.nlink == maxLinks { - panic("memfs.inode.incLinksLocked() called with maximum link count") + panic("tmpfs.inode.incLinksLocked() called with maximum link count") } atomic.AddUint32(&i.nlink, 1) } -- cgit v1.2.3 From 9b5e305e05ef3ad51778981062d6152cea1cd4fb Mon Sep 17 00:00:00 2001 From: Jamie Liu Date: Tue, 21 Apr 2020 12:16:42 -0700 Subject: Remove filesystem structure from vfs.Dentry. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This change: - Drastically simplifies the synchronization model: filesystem structure is both implementation-defined and implementation-synchronized. - Allows implementations of vfs.DentryImpl to use implementation-specific dentry types, reducing casts during path traversal. - Doesn't require dentries representing non-directory files to waste space on a map of children. - Allows dentry revalidation and mount lookup to be correctly ordered (fixed FIXME in fsimpl/gofer/filesystem.go). - Removes the need to have two separate maps in gofer.dentry (dentry.vfsd.children and dentry.negativeChildren) for positive and negative lookups respectively. //pkg/sentry/fsimpl/tmpfs/benchmark_test.go: name old time/op new time/op delta VFS2TmpfsStat/1-112 172ns ± 4% 165ns ± 3% -4.08% (p=0.002 n=9+9) VFS2TmpfsStat/2-112 199ns ± 3% 195ns ±10% ~ (p=0.132 n=8+9) VFS2TmpfsStat/3-112 230ns ± 2% 216ns ± 2% -6.15% (p=0.000 n=8+8) VFS2TmpfsStat/8-112 390ns ± 2% 358ns ± 4% -8.33% (p=0.000 n=9+8) VFS2TmpfsStat/64-112 2.20µs ± 3% 2.01µs ± 3% -8.48% (p=0.000 n=10+8) VFS2TmpfsStat/100-112 3.42µs ± 9% 3.08µs ± 2% -9.82% (p=0.000 n=9+8) VFS2TmpfsMountStat/1-112 278ns ± 1% 286ns ±15% ~ (p=0.712 n=8+10) VFS2TmpfsMountStat/2-112 311ns ± 4% 298ns ± 2% -4.27% (p=0.000 n=9+8) VFS2TmpfsMountStat/3-112 339ns ± 3% 330ns ± 9% ~ (p=0.070 n=8+9) VFS2TmpfsMountStat/8-112 503ns ± 3% 466ns ± 3% -7.38% (p=0.000 n=8+8) VFS2TmpfsMountStat/64-112 2.53µs ±16% 2.17µs ± 7% -14.19% (p=0.000 n=10+9) VFS2TmpfsMountStat/100-112 3.60µs ± 4% 3.30µs ± 8% -8.33% (p=0.001 n=8+9) Updates #1035 PiperOrigin-RevId: 307655892 --- pkg/sentry/fsimpl/ext/BUILD | 12 ++ pkg/sentry/fsimpl/ext/dentry.go | 4 + pkg/sentry/fsimpl/ext/directory.go | 21 ++- pkg/sentry/fsimpl/ext/filesystem.go | 54 ++++-- pkg/sentry/fsimpl/ext/inode.go | 2 +- pkg/sentry/fsimpl/gofer/BUILD | 12 ++ pkg/sentry/fsimpl/gofer/directory.go | 55 +++--- pkg/sentry/fsimpl/gofer/filesystem.go | 202 +++++++++++--------- pkg/sentry/fsimpl/gofer/gofer.go | 66 ++++--- pkg/sentry/fsimpl/gofer/gofer_test.go | 3 +- pkg/sentry/fsimpl/kernfs/BUILD | 12 ++ pkg/sentry/fsimpl/kernfs/fd_impl_util.go | 2 +- pkg/sentry/fsimpl/kernfs/filesystem.go | 159 +++++++++------- pkg/sentry/fsimpl/kernfs/inode_impl_util.go | 2 +- pkg/sentry/fsimpl/kernfs/kernfs.go | 33 ++-- pkg/sentry/fsimpl/proc/tasks_test.go | 16 +- pkg/sentry/fsimpl/tmpfs/BUILD | 12 ++ pkg/sentry/fsimpl/tmpfs/benchmark_test.go | 7 - pkg/sentry/fsimpl/tmpfs/directory.go | 84 ++++++--- pkg/sentry/fsimpl/tmpfs/filesystem.go | 249 +++++++++++++------------ pkg/sentry/fsimpl/tmpfs/stat_test.go | 12 +- pkg/sentry/fsimpl/tmpfs/tmpfs.go | 82 ++++---- pkg/sentry/vfs/dentry.go | 259 +++++--------------------- pkg/sentry/vfs/file_description.go | 3 +- pkg/sentry/vfs/filesystem.go | 5 +- pkg/sentry/vfs/filesystem_impl_util.go | 26 --- pkg/sentry/vfs/genericfstree/BUILD | 16 ++ pkg/sentry/vfs/genericfstree/genericfstree.go | 80 ++++++++ pkg/sentry/vfs/mount.go | 9 +- pkg/sentry/vfs/pathname.go | 6 +- pkg/sentry/vfs/resolving_path.go | 85 +++------ 31 files changed, 836 insertions(+), 754 deletions(-) create mode 100644 pkg/sentry/vfs/genericfstree/BUILD create mode 100644 pkg/sentry/vfs/genericfstree/genericfstree.go (limited to 'pkg/sentry/fsimpl/tmpfs/filesystem.go') diff --git a/pkg/sentry/fsimpl/ext/BUILD b/pkg/sentry/fsimpl/ext/BUILD index d83d75b3d..a4947c480 100644 --- a/pkg/sentry/fsimpl/ext/BUILD +++ b/pkg/sentry/fsimpl/ext/BUILD @@ -15,6 +15,17 @@ go_template_instance( }, ) +go_template_instance( + name = "fstree", + out = "fstree.go", + package = "ext", + prefix = "generic", + template = "//pkg/sentry/vfs/genericfstree:generic_fstree", + types = { + "Dentry": "dentry", + }, +) + go_library( name = "ext", srcs = [ @@ -26,6 +37,7 @@ go_library( "extent_file.go", "file_description.go", "filesystem.go", + "fstree.go", "inode.go", "regular_file.go", "symlink.go", diff --git a/pkg/sentry/fsimpl/ext/dentry.go b/pkg/sentry/fsimpl/ext/dentry.go index a080cb189..bfbd7c3d4 100644 --- a/pkg/sentry/fsimpl/ext/dentry.go +++ b/pkg/sentry/fsimpl/ext/dentry.go @@ -22,6 +22,10 @@ import ( type dentry struct { vfsd vfs.Dentry + // Protected by filesystem.mu. + parent *dentry + name string + // inode is the inode represented by this dentry. Multiple Dentries may // share a single non-directory Inode (with hard links). inode is // immutable. diff --git a/pkg/sentry/fsimpl/ext/directory.go b/pkg/sentry/fsimpl/ext/directory.go index bd6ede995..12b875c8f 100644 --- a/pkg/sentry/fsimpl/ext/directory.go +++ b/pkg/sentry/fsimpl/ext/directory.go @@ -21,7 +21,6 @@ import ( "gvisor.dev/gvisor/pkg/log" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fsimpl/ext/disklayout" - "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" @@ -31,6 +30,10 @@ import ( type directory struct { inode inode + // childCache maps filenames to dentries for children for which dentries + // have been instantiated. childCache is protected by filesystem.mu. + childCache map[string]*dentry + // mu serializes the changes to childList. // Lock Order (outermost locks must be taken first): // directory.mu @@ -50,9 +53,13 @@ type directory struct { childMap map[string]*dirent } -// newDirectroy is the directory constructor. -func newDirectroy(inode inode, newDirent bool) (*directory, error) { - file := &directory{inode: inode, childMap: make(map[string]*dirent)} +// newDirectory is the directory constructor. +func newDirectory(inode inode, newDirent bool) (*directory, error) { + file := &directory{ + inode: inode, + childCache: make(map[string]*dentry), + childMap: make(map[string]*dirent), + } file.inode.impl = file // Initialize childList by reading dirents from the underlying file. @@ -299,9 +306,3 @@ func (fd *directoryFD) Seek(ctx context.Context, offset int64, whence int32) (in fd.off = offset return offset, nil } - -// ConfigureMMap implements vfs.FileDescriptionImpl.ConfigureMMap. -func (fd *directoryFD) ConfigureMMap(ctx context.Context, opts *memmap.MMapOpts) error { - // mmap(2) specifies that EACCESS should be returned for non-regular file fds. - return syserror.EACCES -} diff --git a/pkg/sentry/fsimpl/ext/filesystem.go b/pkg/sentry/fsimpl/ext/filesystem.go index afea58f65..2c22a04af 100644 --- a/pkg/sentry/fsimpl/ext/filesystem.go +++ b/pkg/sentry/fsimpl/ext/filesystem.go @@ -89,14 +89,33 @@ func stepLocked(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, inode *inode, write boo } for { - nextVFSD, err := rp.ResolveComponent(vfsd) - if err != nil { - return nil, nil, err + name := rp.Component() + if name == "." { + rp.Advance() + return vfsd, inode, nil } - if nextVFSD == nil { - // Since the Dentry tree is not the sole source of truth for extfs, if it's - // not in the Dentry tree, it might need to be pulled from disk. - childDirent, ok := inode.impl.(*directory).childMap[rp.Component()] + d := vfsd.Impl().(*dentry) + if name == ".." { + isRoot, err := rp.CheckRoot(vfsd) + if err != nil { + return nil, nil, err + } + if isRoot || d.parent == nil { + rp.Advance() + return vfsd, inode, nil + } + if err := rp.CheckMount(&d.parent.vfsd); err != nil { + return nil, nil, err + } + rp.Advance() + return &d.parent.vfsd, d.parent.inode, nil + } + + dir := inode.impl.(*directory) + child, ok := dir.childCache[name] + if !ok { + // We may need to instantiate a new dentry for this child. + childDirent, ok := dir.childMap[name] if !ok { // The underlying inode does not exist on disk. return nil, nil, syserror.ENOENT @@ -115,21 +134,22 @@ func stepLocked(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, inode *inode, write boo } // incRef because this is being added to the dentry tree. childInode.incRef() - child := newDentry(childInode) - vfsd.InsertChild(&child.vfsd, rp.Component()) - - // Continue as usual now that nextVFSD is not nil. - nextVFSD = &child.vfsd + child = newDentry(childInode) + child.parent = d + child.name = name + dir.childCache[name] = child + } + if err := rp.CheckMount(&child.vfsd); err != nil { + return nil, nil, err } - nextInode := nextVFSD.Impl().(*dentry).inode - if nextInode.isSymlink() && rp.ShouldFollowSymlink() { - if err := rp.HandleSymlink(inode.impl.(*symlink).target); err != nil { + if child.inode.isSymlink() && rp.ShouldFollowSymlink() { + if err := rp.HandleSymlink(child.inode.impl.(*symlink).target); err != nil { return nil, nil, err } continue } rp.Advance() - return nextVFSD, nextInode, nil + return &child.vfsd, child.inode, nil } } @@ -515,5 +535,5 @@ func (fs *filesystem) RemovexattrAt(ctx context.Context, rp *vfs.ResolvingPath, func (fs *filesystem) PrependPath(ctx context.Context, vfsroot, vd vfs.VirtualDentry, b *fspath.Builder) error { fs.mu.RLock() defer fs.mu.RUnlock() - return vfs.GenericPrependPath(vfsroot, vd, b) + return genericPrependPath(vfsroot, vd.Mount(), vd.Dentry().Impl().(*dentry), b) } diff --git a/pkg/sentry/fsimpl/ext/inode.go b/pkg/sentry/fsimpl/ext/inode.go index a39a37318..a98512350 100644 --- a/pkg/sentry/fsimpl/ext/inode.go +++ b/pkg/sentry/fsimpl/ext/inode.go @@ -136,7 +136,7 @@ func newInode(fs *filesystem, inodeNum uint32) (*inode, error) { } return &f.inode, nil case linux.ModeDirectory: - f, err := newDirectroy(inode, fs.sb.IncompatibleFeatures().DirentFileType) + f, err := newDirectory(inode, fs.sb.IncompatibleFeatures().DirentFileType) if err != nil { return nil, err } diff --git a/pkg/sentry/fsimpl/gofer/BUILD b/pkg/sentry/fsimpl/gofer/BUILD index 99d1e3f8f..acd061905 100644 --- a/pkg/sentry/fsimpl/gofer/BUILD +++ b/pkg/sentry/fsimpl/gofer/BUILD @@ -15,12 +15,24 @@ go_template_instance( }, ) +go_template_instance( + name = "fstree", + out = "fstree.go", + package = "gofer", + prefix = "generic", + template = "//pkg/sentry/vfs/genericfstree:generic_fstree", + types = { + "Dentry": "dentry", + }, +) + go_library( name = "gofer", srcs = [ "dentry_list.go", "directory.go", "filesystem.go", + "fstree.go", "gofer.go", "handle.go", "handle_unsafe.go", diff --git a/pkg/sentry/fsimpl/gofer/directory.go b/pkg/sentry/fsimpl/gofer/directory.go index 49d9f859b..d02691232 100644 --- a/pkg/sentry/fsimpl/gofer/directory.go +++ b/pkg/sentry/fsimpl/gofer/directory.go @@ -29,13 +29,25 @@ func (d *dentry) isDir() bool { return d.fileType() == linux.S_IFDIR } +// Preconditions: filesystem.renameMu must be locked. d.dirMu must be locked. +// d.isDir(). child must be a newly-created dentry that has never had a parent. +func (d *dentry) cacheNewChildLocked(child *dentry, name string) { + d.IncRef() // reference held by child on its parent + child.parent = d + child.name = name + if d.children == nil { + d.children = make(map[string]*dentry) + } + d.children[name] = child +} + // Preconditions: d.dirMu must be locked. d.isDir(). fs.opts.interop != // InteropModeShared. func (d *dentry) cacheNegativeChildLocked(name string) { - if d.negativeChildren == nil { - d.negativeChildren = make(map[string]struct{}) + if d.children == nil { + d.children = make(map[string]*dentry) } - d.negativeChildren[name] = struct{}{} + d.children[name] = nil } type directoryFD struct { @@ -80,34 +92,32 @@ func (fd *directoryFD) IterDirents(ctx context.Context, cb vfs.IterDirentsCallba // Preconditions: d.isDir(). There exists at least one directoryFD representing d. func (d *dentry) getDirents(ctx context.Context) ([]vfs.Dirent, error) { - // 9P2000.L's readdir does not specify behavior in the presence of - // concurrent mutation of an iterated directory, so implementations may - // duplicate or omit entries in this case, which violates POSIX semantics. - // Thus we read all directory entries while holding d.dirMu to exclude - // directory mutations. (Note that it is impossible for the client to - // exclude concurrent mutation from other remote filesystem users. Since - // there is no way to detect if the server has incorrectly omitted - // directory entries, we simply assume that the server is well-behaved - // under InteropModeShared.) This is inconsistent with Linux (which appears - // to assume that directory fids have the correct semantics, and translates - // struct file_operations::readdir calls directly to readdir RPCs), but is - // consistent with VFS1. - // - // NOTE(b/135560623): In particular, some gofer implementations may not - // retain state between calls to Readdir, so may not provide a coherent - // directory stream across in the presence of mutation. - + // NOTE(b/135560623): 9P2000.L's readdir does not specify behavior in the + // presence of concurrent mutation of an iterated directory, so + // implementations may duplicate or omit entries in this case, which + // violates POSIX semantics. Thus we read all directory entries while + // holding d.dirMu to exclude directory mutations. (Note that it is + // impossible for the client to exclude concurrent mutation from other + // remote filesystem users. Since there is no way to detect if the server + // has incorrectly omitted directory entries, we simply assume that the + // server is well-behaved under InteropModeShared.) This is inconsistent + // with Linux (which appears to assume that directory fids have the correct + // semantics, and translates struct file_operations::readdir calls directly + // to readdir RPCs), but is consistent with VFS1. + + // filesystem.renameMu is needed for d.parent, and must be locked before + // dentry.dirMu. d.fs.renameMu.RLock() - defer d.fs.renameMu.RUnlock() d.dirMu.Lock() defer d.dirMu.Unlock() if d.dirents != nil { + d.fs.renameMu.RUnlock() return d.dirents, nil } // It's not clear if 9P2000.L's readdir is expected to return "." and "..", // so we generate them here. - parent := d.vfsd.ParentOrSelf().Impl().(*dentry) + parent := genericParentOrSelf(d) dirents := []vfs.Dirent{ { Name: ".", @@ -122,6 +132,7 @@ func (d *dentry) getDirents(ctx context.Context) ([]vfs.Dirent, error) { NextOff: 2, }, } + d.fs.renameMu.RUnlock() off := uint64(0) const count = 64 * 1024 // for consistency with the vfs1 client d.handleMu.RLock() diff --git a/pkg/sentry/fsimpl/gofer/filesystem.go b/pkg/sentry/fsimpl/gofer/filesystem.go index cd744bf5e..43e863c61 100644 --- a/pkg/sentry/fsimpl/gofer/filesystem.go +++ b/pkg/sentry/fsimpl/gofer/filesystem.go @@ -116,6 +116,8 @@ func putDentrySlice(ds *[]*dentry) { // Preconditions: fs.renameMu must be locked. d.dirMu must be locked. // !rp.Done(). If fs.opts.interop == InteropModeShared, then d's cached // metadata must be up to date. +// +// Postconditions: The returned dentry's cached metadata is up to date. func (fs *filesystem) stepLocked(ctx context.Context, rp *vfs.ResolvingPath, d *dentry, ds **[]*dentry) (*dentry, error) { if !d.isDir() { return nil, syserror.ENOTDIR @@ -130,39 +132,42 @@ afterSymlink: return d, nil } if name == ".." { - parentVFSD, err := rp.ResolveParent(&d.vfsd) - if err != nil { + if isRoot, err := rp.CheckRoot(&d.vfsd); err != nil { + return nil, err + } else if isRoot || d.parent == nil { + rp.Advance() + return d, nil + } + // We must assume that d.parent is correct, because if d has been moved + // elsewhere in the remote filesystem so that its parent has changed, + // we have no way of determining its new parent's location in the + // filesystem. + // + // Call rp.CheckMount() before updating d.parent's metadata, since if + // we traverse to another mount then d.parent's metadata is irrelevant. + if err := rp.CheckMount(&d.parent.vfsd); err != nil { return nil, err } - parent := parentVFSD.Impl().(*dentry) - if fs.opts.interop == InteropModeShared { - // We must assume that parentVFSD is correct, because if d has been - // moved elsewhere in the remote filesystem so that its parent has - // changed, we have no way of determining its new parent's location - // in the filesystem. Get updated metadata for parentVFSD. - _, attrMask, attr, err := parent.file.getAttr(ctx, dentryAttrMask()) + if fs.opts.interop == InteropModeShared && d != d.parent { + _, attrMask, attr, err := d.parent.file.getAttr(ctx, dentryAttrMask()) if err != nil { return nil, err } - parent.updateFromP9Attrs(attrMask, &attr) + d.parent.updateFromP9Attrs(attrMask, &attr) } rp.Advance() - return parent, nil + return d.parent, nil } - childVFSD, err := rp.ResolveChild(&d.vfsd, name) - if err != nil { - return nil, err - } - // FIXME(jamieliu): Linux performs revalidation before mount lookup - // (fs/namei.c:lookup_fast() => __d_lookup_rcu(), d_revalidate(), - // __follow_mount_rcu()). - child, err := fs.revalidateChildLocked(ctx, rp.VirtualFilesystem(), d, name, childVFSD, ds) + child, err := fs.getChildLocked(ctx, rp.VirtualFilesystem(), d, name, ds) if err != nil { return nil, err } if child == nil { return nil, syserror.ENOENT } + if err := rp.CheckMount(&child.vfsd); err != nil { + return nil, err + } if child.isSymlink() && rp.ShouldFollowSymlink() { target, err := child.readlink(ctx, rp.Mount()) if err != nil { @@ -177,38 +182,37 @@ afterSymlink: return child, nil } -// revalidateChildLocked must be called after a call to parent.vfsd.Child(name) -// or vfs.ResolvingPath.ResolveChild(name) returns childVFSD (which may be -// nil) to verify that the returned child (or lack thereof) is correct. If no file -// exists at name, revalidateChildLocked returns (nil, nil). +// getChildLocked returns a dentry representing the child of parent with the +// given name. If no such child exists, getChildLocked returns (nil, nil). // // Preconditions: fs.renameMu must be locked. parent.dirMu must be locked. // parent.isDir(). name is not "." or "..". // -// Postconditions: If revalidateChildLocked returns a non-nil dentry, its -// cached metadata is up to date. -func (fs *filesystem) revalidateChildLocked(ctx context.Context, vfsObj *vfs.VirtualFilesystem, parent *dentry, name string, childVFSD *vfs.Dentry, ds **[]*dentry) (*dentry, error) { - if childVFSD != nil && fs.opts.interop != InteropModeShared { - // We have a cached dentry that is assumed to be correct. - return childVFSD.Impl().(*dentry), nil - } - // We either don't have a cached dentry or need to verify that it's still - // correct, either of which requires a remote lookup. Check if this name is - // valid before performing the lookup. +// Postconditions: If getChildLocked returns a non-nil dentry, its cached +// metadata is up to date. +func (fs *filesystem) getChildLocked(ctx context.Context, vfsObj *vfs.VirtualFilesystem, parent *dentry, name string, ds **[]*dentry) (*dentry, error) { if len(name) > maxFilenameLen { return nil, syserror.ENAMETOOLONG } - // Check if we've already cached this lookup with a negative result. - if _, ok := parent.negativeChildren[name]; ok { - return nil, nil + child, ok := parent.children[name] + if ok && fs.opts.interop != InteropModeShared { + // Whether child is nil or not, it is cached information that is + // assumed to be correct. + return child, nil } - // Perform the remote lookup. + // We either don't have cached information or need to verify that it's + // still correct, either of which requires a remote lookup. Check if this + // name is valid before performing the lookup. + return fs.revalidateChildLocked(ctx, vfsObj, parent, name, child, ds) +} + +// Preconditions: As for getChildLocked. +func (fs *filesystem) revalidateChildLocked(ctx context.Context, vfsObj *vfs.VirtualFilesystem, parent *dentry, name string, child *dentry, ds **[]*dentry) (*dentry, error) { qid, file, attrMask, attr, err := parent.file.walkGetAttrOne(ctx, name) if err != nil && err != syserror.ENOENT { return nil, err } - if childVFSD != nil { - child := childVFSD.Impl().(*dentry) + if child != nil { if !file.isNil() && qid.Path == child.ino { // The file at this path hasn't changed. Just update cached // metadata. @@ -219,9 +223,8 @@ func (fs *filesystem) revalidateChildLocked(ctx context.Context, vfsObj *vfs.Vir // The file at this path has changed or no longer exists. Remove // the stale dentry from the tree, and re-evaluate its caching // status (i.e. if it has 0 references, drop it). - vfsObj.ForceDeleteDentry(childVFSD) + vfsObj.InvalidateDentry(&child.vfsd) *ds = appendDentry(*ds, child) - childVFSD = nil } if file.isNil() { // No file exists at this path now. Cache the negative lookup if @@ -232,13 +235,12 @@ func (fs *filesystem) revalidateChildLocked(ctx context.Context, vfsObj *vfs.Vir return nil, nil } // Create a new dentry representing the file. - child, err := fs.newDentry(ctx, file, qid, attrMask, &attr) + child, err = fs.newDentry(ctx, file, qid, attrMask, &attr) if err != nil { file.close(ctx) return nil, err } - parent.IncRef() // reference held by child on its parent - parent.vfsd.InsertChild(&child.vfsd, name) + parent.cacheNewChildLocked(child, name) // For now, child has 0 references, so our caller should call // child.checkCachingLocked(). *ds = appendDentry(*ds, child) @@ -318,9 +320,6 @@ func (fs *filesystem) doCreateAt(ctx context.Context, rp *vfs.ResolvingPath, dir if err := parent.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec); err != nil { return err } - if parent.isDeleted() { - return syserror.ENOENT - } name := rp.Component() if name == "." || name == ".." { return syserror.EEXIST @@ -331,6 +330,9 @@ func (fs *filesystem) doCreateAt(ctx context.Context, rp *vfs.ResolvingPath, dir if !dir && rp.MustBeDir() { return syserror.ENOENT } + if parent.isDeleted() { + return syserror.ENOENT + } mnt := rp.Mount() if err := mnt.CheckBeginWrite(); err != nil { return err @@ -348,7 +350,7 @@ func (fs *filesystem) doCreateAt(ctx context.Context, rp *vfs.ResolvingPath, dir // it's used. return create(parent, name) } - if parent.vfsd.Child(name) != nil { + if child := parent.children[name]; child != nil { return syserror.EEXIST } // No cached dentry exists; however, there might still be an existing file @@ -356,10 +358,11 @@ func (fs *filesystem) doCreateAt(ctx context.Context, rp *vfs.ResolvingPath, dir if err := create(parent, name); err != nil { return err } - if fs.opts.interop != InteropModeShared { - parent.touchCMtime() - } - delete(parent.negativeChildren, name) + parent.touchCMtime() + // Either parent.children[name] doesn't exist (in which case this is a + // no-op) or is nil (in which case this erases the now-stale information + // that the file doesn't exist). + delete(parent.children, name) parent.dirents = nil return nil } @@ -407,56 +410,55 @@ func (fs *filesystem) unlinkAt(ctx context.Context, rp *vfs.ResolvingPath, dir b defer mntns.DecRef() parent.dirMu.Lock() defer parent.dirMu.Unlock() - childVFSD := parent.vfsd.Child(name) - var child *dentry + child, ok := parent.children[name] + if ok && child == nil { + return syserror.ENOENT + } // We only need a dentry representing the file at name if it can be a mount - // point. If childVFSD is nil, then it can't be a mount point. If childVFSD - // is non-nil but stale, the actual file can't be a mount point either; we + // point. If child is nil, then it can't be a mount point. If child is + // non-nil but stale, the actual file can't be a mount point either; we // detect this case by just speculatively calling PrepareDeleteDentry and // only revalidating the dentry if that fails (indicating that the existing // dentry is a mount point). - if childVFSD != nil { - child = childVFSD.Impl().(*dentry) - if err := vfsObj.PrepareDeleteDentry(mntns, childVFSD); err != nil { - child, err = fs.revalidateChildLocked(ctx, vfsObj, parent, name, childVFSD, &ds) + if child != nil { + if err := vfsObj.PrepareDeleteDentry(mntns, &child.vfsd); err != nil { + if fs.opts.interop != InteropModeShared { + return err + } + child, err = fs.revalidateChildLocked(ctx, vfsObj, parent, name, child, &ds) if err != nil { return err } if child != nil { - childVFSD = &child.vfsd - if err := vfsObj.PrepareDeleteDentry(mntns, childVFSD); err != nil { + if err := vfsObj.PrepareDeleteDentry(mntns, &child.vfsd); err != nil { return err } - } else { - childVFSD = nil } } - } else if _, ok := parent.negativeChildren[name]; ok { - return syserror.ENOENT } flags := uint32(0) if dir { if child != nil && !child.isDir() { - vfsObj.AbortDeleteDentry(childVFSD) + vfsObj.AbortDeleteDentry(&child.vfsd) return syserror.ENOTDIR } flags = linux.AT_REMOVEDIR } else { if child != nil && child.isDir() { - vfsObj.AbortDeleteDentry(childVFSD) + vfsObj.AbortDeleteDentry(&child.vfsd) return syserror.EISDIR } if rp.MustBeDir() { - if childVFSD != nil { - vfsObj.AbortDeleteDentry(childVFSD) + if child != nil { + vfsObj.AbortDeleteDentry(&child.vfsd) } return syserror.ENOTDIR } } err = parent.file.unlinkAt(ctx, name, flags) if err != nil { - if childVFSD != nil { - vfsObj.AbortDeleteDentry(childVFSD) + if child != nil { + vfsObj.AbortDeleteDentry(&child.vfsd) } return err } @@ -467,10 +469,12 @@ func (fs *filesystem) unlinkAt(ctx context.Context, rp *vfs.ResolvingPath, dir b } parent.cacheNegativeChildLocked(name) parent.dirents = nil + } else { + delete(parent.children, name) } if child != nil { child.setDeleted() - vfsObj.CommitDeleteDentry(childVFSD) + vfsObj.CommitDeleteDentry(&child.vfsd) ds = appendDentry(ds, child) } return nil @@ -806,16 +810,14 @@ func (d *dentry) createAndOpenChildLocked(ctx context.Context, rp *vfs.Resolving // eligible for caching yet, so we don't need to append to a dentry slice.) child.refs = 1 // Insert the dentry into the tree. - d.IncRef() // reference held by child on its parent d - d.vfsd.InsertChild(&child.vfsd, name) + d.cacheNewChildLocked(child, name) if d.fs.opts.interop != InteropModeShared { - delete(d.negativeChildren, name) + d.touchCMtime() d.dirents = nil } // Finally, construct a file description representing the created file. var childVFSFD *vfs.FileDescription - mnt.IncRef() if useRegularFileFD { fd := ®ularFileFD{} if err := fd.vfsfd.Init(fd, opts.Flags, mnt, &child.vfsd, &vfs.FileDescriptionOptions{ @@ -840,9 +842,6 @@ func (d *dentry) createAndOpenChildLocked(ctx context.Context, rp *vfs.Resolving } childVFSFD = &fd.vfsfd } - if d.fs.opts.interop != InteropModeShared { - d.touchCMtime() - } return childVFSFD, nil } @@ -902,7 +901,7 @@ func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa // directory, we need to check for write permission on it. oldParent.dirMu.Lock() defer oldParent.dirMu.Unlock() - renamed, err := fs.revalidateChildLocked(ctx, vfsObj, oldParent, oldName, oldParent.vfsd.Child(oldName), &ds) + renamed, err := fs.getChildLocked(ctx, vfsObj, oldParent, oldName, &ds) if err != nil { return err } @@ -910,7 +909,7 @@ func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa return syserror.ENOENT } if renamed.isDir() { - if renamed == newParent || renamed.vfsd.IsAncestorOf(&newParent.vfsd) { + if renamed == newParent || genericIsAncestorDentry(renamed, newParent) { return syserror.EINVAL } if oldParent != newParent { @@ -934,16 +933,17 @@ func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa if newParent.isDeleted() { return syserror.ENOENT } - replacedVFSD := newParent.vfsd.Child(newName) - var replaced *dentry + replaced := newParent.children[newName] // This is similar to unlinkAt, except: // - // - We revalidate the replaced dentry unconditionally for simplicity. + // - If a dentry exists for the file to be replaced, we revalidate it + // unconditionally (instead of only if PrepareRenameDentry fails) for + // simplicity. // // - If rp.MustBeDir(), then we need a dentry representing the replaced // file regardless to confirm that it's a directory. - if replacedVFSD != nil || rp.MustBeDir() { - replaced, err = fs.revalidateChildLocked(ctx, vfsObj, newParent, newName, replacedVFSD, &ds) + if replaced != nil || rp.MustBeDir() { + replaced, err = fs.getChildLocked(ctx, rp.VirtualFilesystem(), newParent, newName, &ds) if err != nil { return err } @@ -957,11 +957,12 @@ func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa return syserror.ENOTDIR } } - replacedVFSD = &replaced.vfsd - } else { - replacedVFSD = nil } } + var replacedVFSD *vfs.Dentry + if replaced != nil { + replacedVFSD = &replaced.vfsd + } if oldParent == newParent && oldName == newName { return nil @@ -978,7 +979,6 @@ func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa if fs.opts.interop != InteropModeShared { oldParent.cacheNegativeChildLocked(oldName) oldParent.dirents = nil - delete(newParent.negativeChildren, newName) newParent.dirents = nil if renamed.isDir() { oldParent.decLinks() @@ -987,8 +987,24 @@ func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa oldParent.touchCMtime() newParent.touchCMtime() renamed.touchCtime() + } else { + delete(oldParent.children, oldName) + } + if oldParent != newParent { + appendDentry(ds, oldParent) + newParent.IncRef() + } + renamed.parent = newParent + renamed.name = newName + if newParent.children == nil { + newParent.children = make(map[string]*dentry) + } + newParent.children[newName] = renamed + if replaced != nil { + replaced.setDeleted() + appendDentry(ds, replaced) } - vfsObj.CommitRenameReplaceDentry(&renamed.vfsd, &newParent.vfsd, newName, replacedVFSD) + vfsObj.CommitRenameReplaceDentry(&renamed.vfsd, replacedVFSD) return nil } @@ -1131,5 +1147,5 @@ func (fs *filesystem) RemovexattrAt(ctx context.Context, rp *vfs.ResolvingPath, func (fs *filesystem) PrependPath(ctx context.Context, vfsroot, vd vfs.VirtualDentry, b *fspath.Builder) error { fs.renameMu.RLock() defer fs.renameMu.RUnlock() - return vfs.GenericPrependPath(vfsroot, vd, b) + return genericPrependPath(vfsroot, vd.Mount(), vd.Dentry().Impl().(*dentry), b) } diff --git a/pkg/sentry/fsimpl/gofer/gofer.go b/pkg/sentry/fsimpl/gofer/gofer.go index 2485cdb53..293df2545 100644 --- a/pkg/sentry/fsimpl/gofer/gofer.go +++ b/pkg/sentry/fsimpl/gofer/gofer.go @@ -452,6 +452,16 @@ type dentry struct { // fs is the owning filesystem. fs is immutable. fs *filesystem + // parent is this dentry's parent directory. Each dentry holds a reference + // on its parent. If this dentry is a filesystem root, parent is nil. + // parent is protected by filesystem.renameMu. + parent *dentry + + // name is the name of this dentry in its parent. If this dentry is a + // filesystem root, name is the empty string. name is protected by + // filesystem.renameMu. + name string + // We don't support hard links, so each dentry maps 1:1 to an inode. // file is the unopened p9.File that backs this dentry. file is immutable. @@ -469,10 +479,15 @@ type dentry struct { dirMu sync.Mutex - // If this dentry represents a directory, and InteropModeShared is not in - // effect, negativeChildren is a set of child names in this directory that - // are known not to exist. negativeChildren is protected by dirMu. - negativeChildren map[string]struct{} + // If this dentry represents a directory, children contains: + // + // - Mappings of child filenames to dentries representing those children. + // + // - Mappings of child filenames that are known not to exist to nil + // dentries (only if InteropModeShared is not in effect). + // + // children is protected by dirMu. + children map[string]*dentry // If this dentry represents a directory, InteropModeShared is not in // effect, and dirents is not nil, it is a cache of all entries in the @@ -910,9 +925,9 @@ func (d *dentry) checkCachingLocked() { // Dentry has already been destroyed. return } - // Non-child dentries with zero references are no longer reachable by path - // resolution and should be dropped immediately. - if d.vfsd.Parent() == nil || d.vfsd.IsDisowned() { + // Deleted and invalidated dentries with zero references are no longer + // reachable by path resolution and should be dropped immediately. + if d.vfsd.IsDead() { if d.cached { d.fs.cachedDentries.Remove(d) d.fs.cachedDentriesLen-- @@ -937,28 +952,26 @@ func (d *dentry) checkCachingLocked() { d.fs.cachedDentries.Remove(victim) d.fs.cachedDentriesLen-- victim.cached = false - // victim.refs may have become non-zero from an earlier path - // resolution since it was inserted into fs.cachedDentries; see - // dentry.incRefLocked(). Either way, we brought - // fs.cachedDentriesLen back down to fs.opts.maxCachedDentries, so - // we don't loop. + // victim.refs may have become non-zero from an earlier path resolution + // since it was inserted into fs.cachedDentries. if atomic.LoadInt64(&victim.refs) == 0 { - if victimParentVFSD := victim.vfsd.Parent(); victimParentVFSD != nil { - victimParent := victimParentVFSD.Impl().(*dentry) - victimParent.dirMu.Lock() - if !victim.vfsd.IsDisowned() { - // victim can't be a mount point (in any mount - // namespace), since VFS holds references on mount - // points. - d.fs.vfsfs.VirtualFilesystem().ForceDeleteDentry(&victim.vfsd) + if victim.parent != nil { + victim.parent.dirMu.Lock() + if !victim.vfsd.IsDead() { + // Note that victim can't be a mount point (in any mount + // namespace), since VFS holds references on mount points. + d.fs.vfsfs.VirtualFilesystem().InvalidateDentry(&victim.vfsd) + delete(victim.parent.children, victim.name) // We're only deleting the dentry, not the file it // represents, so we don't need to update // victimParent.dirents etc. } - victimParent.dirMu.Unlock() + victim.parent.dirMu.Unlock() } victim.destroyLocked() } + // Whether or not victim was destroyed, we brought fs.cachedDentriesLen + // back down to fs.opts.maxCachedDentries, so we don't loop. } } @@ -1005,12 +1018,11 @@ func (d *dentry) destroyLocked() { d.fs.syncMu.Lock() delete(d.fs.dentries, d) d.fs.syncMu.Unlock() - // Drop the reference held by d on its parent. - if parentVFSD := d.vfsd.Parent(); parentVFSD != nil { - parent := parentVFSD.Impl().(*dentry) - // This is parent.DecRef() without recursive locking of d.fs.renameMu. - if refs := atomic.AddInt64(&parent.refs, -1); refs == 0 { - parent.checkCachingLocked() + // Drop the reference held by d on its parent without recursively locking + // d.fs.renameMu. + if d.parent != nil { + if refs := atomic.AddInt64(&d.parent.refs, -1); refs == 0 { + d.parent.checkCachingLocked() } else if refs < 0 { panic("gofer.dentry.DecRef() called without holding a reference") } diff --git a/pkg/sentry/fsimpl/gofer/gofer_test.go b/pkg/sentry/fsimpl/gofer/gofer_test.go index 82bc239db..4041fb252 100644 --- a/pkg/sentry/fsimpl/gofer/gofer_test.go +++ b/pkg/sentry/fsimpl/gofer/gofer_test.go @@ -48,8 +48,7 @@ func TestDestroyIdempotent(t *testing.T) { if err != nil { t.Fatalf("fs.newDentry(): %v", err) } - parent.IncRef() // reference held by child on its parent. - parent.vfsd.InsertChild(&child.vfsd, "child") + parent.cacheNewChildLocked(child, "child") child.checkCachingLocked() if got := atomic.LoadInt64(&child.refs); got != -1 { diff --git a/pkg/sentry/fsimpl/kernfs/BUILD b/pkg/sentry/fsimpl/kernfs/BUILD index b3d6299d0..ef34cb28a 100644 --- a/pkg/sentry/fsimpl/kernfs/BUILD +++ b/pkg/sentry/fsimpl/kernfs/BUILD @@ -3,6 +3,17 @@ load("//tools/go_generics:defs.bzl", "go_template_instance") licenses(["notice"]) +go_template_instance( + name = "fstree", + out = "fstree.go", + package = "kernfs", + prefix = "generic", + template = "//pkg/sentry/vfs/genericfstree:generic_fstree", + types = { + "Dentry": "Dentry", + }, +) + go_template_instance( name = "slot_list", out = "slot_list.go", @@ -21,6 +32,7 @@ go_library( "dynamic_bytes_file.go", "fd_impl_util.go", "filesystem.go", + "fstree.go", "inode_impl_util.go", "kernfs.go", "slot_list.go", diff --git a/pkg/sentry/fsimpl/kernfs/fd_impl_util.go b/pkg/sentry/fsimpl/kernfs/fd_impl_util.go index bfa786c88..e8a4670b8 100644 --- a/pkg/sentry/fsimpl/kernfs/fd_impl_util.go +++ b/pkg/sentry/fsimpl/kernfs/fd_impl_util.go @@ -129,7 +129,7 @@ func (fd *GenericDirectoryFD) IterDirents(ctx context.Context, cb vfs.IterDirent // Handle "..". if fd.off == 1 { - parentInode := vfsd.ParentOrSelf().Impl().(*Dentry).inode + parentInode := genericParentOrSelf(vfsd.Impl().(*Dentry)).inode stat, err := parentInode.Stat(vfsFS, opts) if err != nil { return err diff --git a/pkg/sentry/fsimpl/kernfs/filesystem.go b/pkg/sentry/fsimpl/kernfs/filesystem.go index baf81b4db..01c23d192 100644 --- a/pkg/sentry/fsimpl/kernfs/filesystem.go +++ b/pkg/sentry/fsimpl/kernfs/filesystem.go @@ -56,25 +56,28 @@ afterSymlink: return vfsd, nil } if name == ".." { - nextVFSD, err := rp.ResolveParent(vfsd) - if err != nil { + if isRoot, err := rp.CheckRoot(vfsd); err != nil { + return nil, err + } else if isRoot || d.parent == nil { + rp.Advance() + return vfsd, nil + } + if err := rp.CheckMount(&d.parent.vfsd); err != nil { return nil, err } rp.Advance() - return nextVFSD, nil + return &d.parent.vfsd, nil } if len(name) > linux.NAME_MAX { return nil, syserror.ENAMETOOLONG } d.dirMu.Lock() - nextVFSD, err := rp.ResolveChild(vfsd, name) + next, err := fs.revalidateChildLocked(ctx, rp.VirtualFilesystem(), d, name, d.children[name]) + d.dirMu.Unlock() if err != nil { - d.dirMu.Unlock() return nil, err } - next, err := fs.revalidateChildLocked(ctx, rp.VirtualFilesystem(), d, name, nextVFSD) - d.dirMu.Unlock() - if err != nil { + if err := rp.CheckMount(&next.vfsd); err != nil { return nil, err } // Resolve any symlink at current path component. @@ -108,17 +111,17 @@ afterSymlink: // parent.dirMu must be locked. parent.isDir(). name is not "." or "..". // // Postconditions: Caller must call fs.processDeferredDecRefs*. -func (fs *Filesystem) revalidateChildLocked(ctx context.Context, vfsObj *vfs.VirtualFilesystem, parent *Dentry, name string, childVFSD *vfs.Dentry) (*Dentry, error) { - if childVFSD != nil { +func (fs *Filesystem) revalidateChildLocked(ctx context.Context, vfsObj *vfs.VirtualFilesystem, parent *Dentry, name string, child *Dentry) (*Dentry, error) { + if child != nil { // Cached dentry exists, revalidate. - child := childVFSD.Impl().(*Dentry) if !child.inode.Valid(ctx) { - vfsObj.ForceDeleteDentry(childVFSD) - fs.deferDecRef(childVFSD) // Reference from Lookup. - childVFSD = nil + delete(parent.children, name) + vfsObj.InvalidateDentry(&child.vfsd) + fs.deferDecRef(&child.vfsd) // Reference from Lookup. + child = nil } } - if childVFSD == nil { + if child == nil { // Dentry isn't cached; it either doesn't exist or failed // revalidation. Attempt to resolve it via Lookup. // @@ -126,15 +129,15 @@ func (fs *Filesystem) revalidateChildLocked(ctx context.Context, vfsObj *vfs.Vir // *(kernfs.)Dentry, not *vfs.Dentry, since (kernfs.)Filesystem assumes // that all dentries in the filesystem are (kernfs.)Dentry and performs // vfs.DentryImpl casts accordingly. - var err error - childVFSD, err = parent.inode.Lookup(ctx, name) + childVFSD, err := parent.inode.Lookup(ctx, name) if err != nil { return nil, err } // Reference on childVFSD dropped by a corresponding Valid. - parent.insertChildLocked(name, childVFSD) + child = childVFSD.Impl().(*Dentry) + parent.insertChildLocked(name, child) } - return childVFSD.Impl().(*Dentry), nil + return child, nil } // walkExistingLocked resolves rp to an existing file. @@ -203,14 +206,11 @@ func checkCreateLocked(ctx context.Context, rp *vfs.ResolvingPath, parentVFSD *v if len(pc) > linux.NAME_MAX { return "", syserror.ENAMETOOLONG } - childVFSD, err := rp.ResolveChild(parentVFSD, pc) - if err != nil { - return "", err - } - if childVFSD != nil { + // FIXME(gvisor.dev/issue/1193): Data race due to not holding dirMu. + if _, ok := parentVFSD.Impl().(*Dentry).children[pc]; ok { return "", syserror.EEXIST } - if parentVFSD.IsDisowned() { + if parentVFSD.IsDead() { return "", syserror.ENOENT } return pc, nil @@ -220,14 +220,14 @@ func checkCreateLocked(ctx context.Context, rp *vfs.ResolvingPath, parentVFSD *v // // Preconditions: Filesystem.mu must be locked for at least reading. func checkDeleteLocked(ctx context.Context, rp *vfs.ResolvingPath, vfsd *vfs.Dentry) error { - parentVFSD := vfsd.Parent() - if parentVFSD == nil { + parent := vfsd.Impl().(*Dentry).parent + if parent == nil { return syserror.EBUSY } - if parentVFSD.IsDisowned() { + if parent.vfsd.IsDead() { return syserror.ENOENT } - if err := parentVFSD.Impl().(*Dentry).inode.CheckPermissions(ctx, rp.Credentials(), vfs.MayWrite|vfs.MayExec); err != nil { + if err := parent.inode.CheckPermissions(ctx, rp.Credentials(), vfs.MayWrite|vfs.MayExec); err != nil { return err } return nil @@ -321,11 +321,11 @@ func (fs *Filesystem) LinkAt(ctx context.Context, rp *vfs.ResolvingPath, vd vfs. return syserror.EPERM } - child, err := parentInode.NewLink(ctx, pc, d.inode) + childVFSD, err := parentInode.NewLink(ctx, pc, d.inode) if err != nil { return err } - parentVFSD.Impl().(*Dentry).InsertChild(pc, child) + parentVFSD.Impl().(*Dentry).InsertChild(pc, childVFSD.Impl().(*Dentry)) return nil } @@ -349,11 +349,11 @@ func (fs *Filesystem) MkdirAt(ctx context.Context, rp *vfs.ResolvingPath, opts v return err } defer rp.Mount().EndWrite() - child, err := parentInode.NewDir(ctx, pc, opts) + childVFSD, err := parentInode.NewDir(ctx, pc, opts) if err != nil { return err } - parentVFSD.Impl().(*Dentry).InsertChild(pc, child) + parentVFSD.Impl().(*Dentry).InsertChild(pc, childVFSD.Impl().(*Dentry)) return nil } @@ -377,11 +377,11 @@ func (fs *Filesystem) MknodAt(ctx context.Context, rp *vfs.ResolvingPath, opts v return err } defer rp.Mount().EndWrite() - new, err := parentInode.NewNode(ctx, pc, opts) + newVFSD, err := parentInode.NewNode(ctx, pc, opts) if err != nil { return err } - parentVFSD.Impl().(*Dentry).InsertChild(pc, new) + parentVFSD.Impl().(*Dentry).InsertChild(pc, newVFSD.Impl().(*Dentry)) return nil } @@ -449,11 +449,8 @@ afterTrailingSymlink: return nil, syserror.ENAMETOOLONG } // Determine whether or not we need to create a file. - childVFSD, err := rp.ResolveChild(parentVFSD, pc) - if err != nil { - return nil, err - } - if childVFSD == nil { + childVFSD, err := fs.stepExistingLocked(ctx, rp, parentVFSD) + if err == syserror.ENOENT { // Already checked for searchability above; now check for writability. if err := parentInode.CheckPermissions(ctx, rp.Credentials(), vfs.MayWrite); err != nil { return nil, err @@ -463,21 +460,24 @@ afterTrailingSymlink: } defer rp.Mount().EndWrite() // Create and open the child. - child, err := parentInode.NewFile(ctx, pc, opts) + childVFSD, err = parentInode.NewFile(ctx, pc, opts) if err != nil { return nil, err } + child := childVFSD.Impl().(*Dentry) parentVFSD.Impl().(*Dentry).InsertChild(pc, child) - return child.Impl().(*Dentry).inode.Open(rp, child, opts) + return child.inode.Open(rp, childVFSD, opts) + } + if err != nil { + return nil, err } // Open existing file or follow symlink. if mustCreate { return nil, syserror.EEXIST } - childDentry := childVFSD.Impl().(*Dentry) - childInode := childDentry.inode - if rp.ShouldFollowSymlink() && childDentry.isSymlink() { - targetVD, targetPathname, err := childInode.Getlink(ctx) + child := childVFSD.Impl().(*Dentry) + if rp.ShouldFollowSymlink() && child.isSymlink() { + targetVD, targetPathname, err := child.inode.Getlink(ctx) if err != nil { return nil, err } @@ -496,10 +496,10 @@ afterTrailingSymlink: // symlink target. goto afterTrailingSymlink } - if err := childInode.CheckPermissions(ctx, rp.Credentials(), ats); err != nil { + if err := child.inode.CheckPermissions(ctx, rp.Credentials(), ats); err != nil { return nil, err } - return childInode.Open(rp, childVFSD, opts) + return child.inode.Open(rp, &child.vfsd, opts) } // ReadlinkAt implements vfs.FilesystemImpl.ReadlinkAt. @@ -526,15 +526,16 @@ func (fs *Filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa noReplace := opts.Flags&linux.RENAME_NOREPLACE != 0 fs.mu.Lock() - defer fs.mu.Lock() + defer fs.processDeferredDecRefsLocked() + defer fs.mu.Unlock() // Resolve the destination directory first to verify that it's on this // Mount. dstDirVFSD, dstDirInode, err := fs.walkParentDirLocked(ctx, rp) - fs.processDeferredDecRefsLocked() if err != nil { return err } + dstDir := dstDirVFSD.Impl().(*Dentry) mnt := rp.Mount() if mnt != oldParentVD.Mount() { return syserror.EXDEV @@ -547,9 +548,8 @@ func (fs *Filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa srcDirVFSD := oldParentVD.Dentry() srcDir := srcDirVFSD.Impl().(*Dentry) srcDir.dirMu.Lock() - src, err := fs.revalidateChildLocked(ctx, rp.VirtualFilesystem(), srcDir, oldName, srcDirVFSD.Child(oldName)) + src, err := fs.revalidateChildLocked(ctx, rp.VirtualFilesystem(), srcDir, oldName, srcDir.children[oldName]) srcDir.dirMu.Unlock() - fs.processDeferredDecRefsLocked() if err != nil { return err } @@ -561,7 +561,7 @@ func (fs *Filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa } // Can we create the dst dentry? - var dstVFSD *vfs.Dentry + var dst *Dentry pc, err := checkCreateLocked(ctx, rp, dstDirVFSD, dstDirInode) switch err { case nil: @@ -571,38 +571,51 @@ func (fs *Filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa // Won't overwrite existing node since RENAME_NOREPLACE was requested. return syserror.EEXIST } - dstVFSD, err = rp.ResolveChild(dstDirVFSD, pc) - if err != nil { + dst = dstDir.children[pc] + if dst == nil { panic(fmt.Sprintf("Child %q for parent Dentry %+v disappeared inside atomic section?", pc, dstDirVFSD)) } default: return err } + var dstVFSD *vfs.Dentry + if dst != nil { + dstVFSD = &dst.vfsd + } mntns := vfs.MountNamespaceFromContext(ctx) defer mntns.DecRef() virtfs := rp.VirtualFilesystem() - srcDirDentry := srcDirVFSD.Impl().(*Dentry) - dstDirDentry := dstDirVFSD.Impl().(*Dentry) - // We can't deadlock here due to lock ordering because we're protected from // concurrent renames by fs.mu held for writing. - srcDirDentry.dirMu.Lock() - defer srcDirDentry.dirMu.Unlock() - dstDirDentry.dirMu.Lock() - defer dstDirDentry.dirMu.Unlock() + srcDir.dirMu.Lock() + defer srcDir.dirMu.Unlock() + if srcDir != dstDir { + dstDir.dirMu.Lock() + defer dstDir.dirMu.Unlock() + } if err := virtfs.PrepareRenameDentry(mntns, srcVFSD, dstVFSD); err != nil { return err } - srcDirInode := srcDirDentry.inode - replaced, err := srcDirInode.Rename(ctx, srcVFSD.Name(), pc, srcVFSD, dstDirVFSD) + replaced, err := srcDir.inode.Rename(ctx, src.name, pc, srcVFSD, dstDirVFSD) if err != nil { virtfs.AbortRenameDentry(srcVFSD, dstVFSD) return err } - virtfs.CommitRenameReplaceDentry(srcVFSD, dstDirVFSD, pc, replaced) + delete(srcDir.children, src.name) + if srcDir != dstDir { + fs.deferDecRef(srcDirVFSD) + dstDir.IncRef() + } + src.parent = dstDir + src.name = pc + if dstDir.children == nil { + dstDir.children = make(map[string]*Dentry) + } + dstDir.children[pc] = src + virtfs.CommitRenameReplaceDentry(srcVFSD, replaced) return nil } @@ -622,14 +635,15 @@ func (fs *Filesystem) RmdirAt(ctx context.Context, rp *vfs.ResolvingPath) error if err := checkDeleteLocked(ctx, rp, vfsd); err != nil { return err } - if !vfsd.Impl().(*Dentry).isDir() { + d := vfsd.Impl().(*Dentry) + if !d.isDir() { return syserror.ENOTDIR } if inode.HasChildren() { return syserror.ENOTEMPTY } virtfs := rp.VirtualFilesystem() - parentDentry := vfsd.Parent().Impl().(*Dentry) + parentDentry := d.parent parentDentry.dirMu.Lock() defer parentDentry.dirMu.Unlock() @@ -706,11 +720,11 @@ func (fs *Filesystem) SymlinkAt(ctx context.Context, rp *vfs.ResolvingPath, targ return err } defer rp.Mount().EndWrite() - child, err := parentInode.NewSymlink(ctx, pc, target) + childVFSD, err := parentInode.NewSymlink(ctx, pc, target) if err != nil { return err } - parentVFSD.Impl().(*Dentry).InsertChild(pc, child) + parentVFSD.Impl().(*Dentry).InsertChild(pc, childVFSD.Impl().(*Dentry)) return nil } @@ -730,11 +744,12 @@ func (fs *Filesystem) UnlinkAt(ctx context.Context, rp *vfs.ResolvingPath) error if err := checkDeleteLocked(ctx, rp, vfsd); err != nil { return err } - if vfsd.Impl().(*Dentry).isDir() { + d := vfsd.Impl().(*Dentry) + if d.isDir() { return syserror.EISDIR } virtfs := rp.VirtualFilesystem() - parentDentry := vfsd.Parent().Impl().(*Dentry) + parentDentry := d.parent parentDentry.dirMu.Lock() defer parentDentry.dirMu.Unlock() mntns := vfs.MountNamespaceFromContext(ctx) @@ -818,5 +833,5 @@ func (fs *Filesystem) RemovexattrAt(ctx context.Context, rp *vfs.ResolvingPath, func (fs *Filesystem) PrependPath(ctx context.Context, vfsroot, vd vfs.VirtualDentry, b *fspath.Builder) error { fs.mu.RLock() defer fs.mu.RUnlock() - return vfs.GenericPrependPath(vfsroot, vd, b) + return genericPrependPath(vfsroot, vd.Mount(), vd.Dentry().Impl().(*Dentry), b) } diff --git a/pkg/sentry/fsimpl/kernfs/inode_impl_util.go b/pkg/sentry/fsimpl/kernfs/inode_impl_util.go index 65f09af5d..9f526359e 100644 --- a/pkg/sentry/fsimpl/kernfs/inode_impl_util.go +++ b/pkg/sentry/fsimpl/kernfs/inode_impl_util.go @@ -370,7 +370,7 @@ func (o *OrderedChildren) Populate(d *Dentry, children map[string]*Dentry) uint3 if err := o.Insert(name, child.VFSDentry()); err != nil { panic(fmt.Sprintf("Collision when attempting to insert child %q (%+v) into %+v", name, child, d)) } - d.InsertChild(name, child.VFSDentry()) + d.InsertChild(name, child) } return links } diff --git a/pkg/sentry/fsimpl/kernfs/kernfs.go b/pkg/sentry/fsimpl/kernfs/kernfs.go index ad76b9f64..f5041824f 100644 --- a/pkg/sentry/fsimpl/kernfs/kernfs.go +++ b/pkg/sentry/fsimpl/kernfs/kernfs.go @@ -168,17 +168,22 @@ const ( // // Must be initialized by Init prior to first use. type Dentry struct { - refs.AtomicRefCount + vfsd vfs.Dentry - vfsd vfs.Dentry - inode Inode + refs.AtomicRefCount // flags caches useful information about the dentry from the inode. See the // dflags* consts above. Must be accessed by atomic ops. flags uint32 - // dirMu protects vfsd.children for directory dentries. - dirMu sync.Mutex + parent *Dentry + name string + + // dirMu protects children and the names of child Dentries. + dirMu sync.Mutex + children map[string]*Dentry + + inode Inode } // Init initializes this dentry. @@ -222,8 +227,8 @@ func (d *Dentry) DecRef() { func (d *Dentry) destroy() { d.inode.DecRef() // IncRef from Init. d.inode = nil - if parent := d.vfsd.Parent(); parent != nil { - parent.DecRef() // IncRef from Dentry.InsertChild. + if d.parent != nil { + d.parent.DecRef() // IncRef from Dentry.InsertChild. } } @@ -233,7 +238,7 @@ func (d *Dentry) destroy() { // updates the link count on d if required. // // Precondition: d must represent a directory inode. -func (d *Dentry) InsertChild(name string, child *vfs.Dentry) { +func (d *Dentry) InsertChild(name string, child *Dentry) { d.dirMu.Lock() d.insertChildLocked(name, child) d.dirMu.Unlock() @@ -243,13 +248,17 @@ func (d *Dentry) InsertChild(name string, child *vfs.Dentry) { // preconditions. // // Precondition: d.dirMu must be locked. -func (d *Dentry) insertChildLocked(name string, child *vfs.Dentry) { +func (d *Dentry) insertChildLocked(name string, child *Dentry) { if !d.isDir() { panic(fmt.Sprintf("InsertChild called on non-directory Dentry: %+v.", d)) } - vfsDentry := d.VFSDentry() - vfsDentry.IncRef() // DecRef in child's Dentry.destroy. - vfsDentry.InsertChild(child, name) + d.IncRef() // DecRef in child's Dentry.destroy. + child.parent = d + child.name = name + if d.children == nil { + d.children = make(map[string]*Dentry) + } + d.children[name] = child } // The Inode interface maps filesystem-level operations that operate on paths to diff --git a/pkg/sentry/fsimpl/proc/tasks_test.go b/pkg/sentry/fsimpl/proc/tasks_test.go index d0f97c137..19abb5034 100644 --- a/pkg/sentry/fsimpl/proc/tasks_test.go +++ b/pkg/sentry/fsimpl/proc/tasks_test.go @@ -415,36 +415,36 @@ func iterateDir(ctx context.Context, t *testing.T, s *testutil.System, fd *vfs.F if d.Name == "." || d.Name == ".." { continue } - childPath := path.Join(fd.MappedName(ctx), d.Name) + absPath := path.Join(fd.MappedName(ctx), d.Name) if d.Type == linux.DT_LNK { link, err := s.VFS.ReadlinkAt( ctx, auth.CredentialsFromContext(ctx), - &vfs.PathOperation{Root: s.Root, Start: s.Root, Path: fspath.Parse(childPath)}, + &vfs.PathOperation{Root: s.Root, Start: s.Root, Path: fspath.Parse(absPath)}, ) if err != nil { - t.Errorf("vfsfs.ReadlinkAt(%v) failed: %v", childPath, err) + t.Errorf("vfsfs.ReadlinkAt(%v) failed: %v", absPath, err) } else { - t.Logf("Skipping symlink: /proc%s => %s", childPath, link) + t.Logf("Skipping symlink: %s => %s", absPath, link) } continue } - t.Logf("Opening: /proc%s", childPath) + t.Logf("Opening: %s", absPath) child, err := s.VFS.OpenAt( ctx, auth.CredentialsFromContext(ctx), - &vfs.PathOperation{Root: s.Root, Start: s.Root, Path: fspath.Parse(childPath)}, + &vfs.PathOperation{Root: s.Root, Start: s.Root, Path: fspath.Parse(absPath)}, &vfs.OpenOptions{}, ) if err != nil { - t.Errorf("vfsfs.OpenAt(%v) failed: %v", childPath, err) + t.Errorf("vfsfs.OpenAt(%v) failed: %v", absPath, err) continue } defer child.DecRef() stat, err := child.Stat(ctx, vfs.StatOptions{}) if err != nil { - t.Errorf("Stat(%v) failed: %v", childPath, err) + t.Errorf("Stat(%v) failed: %v", absPath, err) } if got := linux.FileMode(stat.Mode).DirentType(); got != d.Type { t.Errorf("wrong file mode, stat: %v, dirent: %v", got, d.Type) diff --git a/pkg/sentry/fsimpl/tmpfs/BUILD b/pkg/sentry/fsimpl/tmpfs/BUILD index 4e6cd3491..a2d9649e7 100644 --- a/pkg/sentry/fsimpl/tmpfs/BUILD +++ b/pkg/sentry/fsimpl/tmpfs/BUILD @@ -15,6 +15,17 @@ go_template_instance( }, ) +go_template_instance( + name = "fstree", + out = "fstree.go", + package = "tmpfs", + prefix = "generic", + template = "//pkg/sentry/vfs/genericfstree:generic_fstree", + types = { + "Dentry": "dentry", + }, +) + go_library( name = "tmpfs", srcs = [ @@ -22,6 +33,7 @@ go_library( "device_file.go", "directory.go", "filesystem.go", + "fstree.go", "named_pipe.go", "regular_file.go", "socket_file.go", diff --git a/pkg/sentry/fsimpl/tmpfs/benchmark_test.go b/pkg/sentry/fsimpl/tmpfs/benchmark_test.go index 651912169..2fb5c4d84 100644 --- a/pkg/sentry/fsimpl/tmpfs/benchmark_test.go +++ b/pkg/sentry/fsimpl/tmpfs/benchmark_test.go @@ -438,13 +438,6 @@ func BenchmarkVFS2TmpfsMountStat(b *testing.B) { filePathBuilder.WriteByte('/') } - // Verify that we didn't create any directories under the mount - // point (i.e. they were all created on the submount). - firstDirName := fmt.Sprintf("%d", depth) - if child := mountPoint.Dentry().Child(firstDirName); child != nil { - b.Fatalf("created directory %q under root mount, not submount", firstDirName) - } - // Create the file that will be stat'd. fd, err := vfsObj.OpenAt(ctx, creds, &vfs.PathOperation{ Root: root, diff --git a/pkg/sentry/fsimpl/tmpfs/directory.go b/pkg/sentry/fsimpl/tmpfs/directory.go index 45712c9b9..f2399981b 100644 --- a/pkg/sentry/fsimpl/tmpfs/directory.go +++ b/pkg/sentry/fsimpl/tmpfs/directory.go @@ -15,35 +15,77 @@ package tmpfs import ( + "sync/atomic" + "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" ) type directory struct { - inode inode + // Since directories can't be hard-linked, each directory can only be + // associated with a single dentry, which we can store in the directory + // struct. + dentry dentry + inode inode + + // childMap maps the names of the directory's children to their dentries. + // childMap is protected by filesystem.mu. + childMap map[string]*dentry - // childList is a list containing (1) child Dentries and (2) fake Dentries + // numChildren is len(childMap), but accessed using atomic memory + // operations to avoid locking in inode.statTo(). + numChildren int64 + + // childList is a list containing (1) child dentries and (2) fake dentries // (with inode == nil) that represent the iteration position of // directoryFDs. childList is used to support directoryFD.IterDirents() - // efficiently. childList is protected by filesystem.mu. + // efficiently. childList is protected by iterMu. + iterMu sync.Mutex childList dentryList } -func (fs *filesystem) newDirectory(creds *auth.Credentials, mode linux.FileMode) *inode { +func (fs *filesystem) newDirectory(creds *auth.Credentials, mode linux.FileMode) *directory { dir := &directory{} dir.inode.init(dir, fs, creds, linux.S_IFDIR|mode) dir.inode.nlink = 2 // from "." and parent directory or ".." for root - return &dir.inode + dir.dentry.inode = &dir.inode + dir.dentry.vfsd.Init(&dir.dentry) + return dir +} + +// Preconditions: filesystem.mu must be locked for writing. dir must not +// already contain a child with the given name. +func (dir *directory) insertChildLocked(child *dentry, name string) { + child.parent = &dir.dentry + child.name = name + if dir.childMap == nil { + dir.childMap = make(map[string]*dentry) + } + dir.childMap[name] = child + atomic.AddInt64(&dir.numChildren, 1) + dir.iterMu.Lock() + dir.childList.PushBack(child) + dir.iterMu.Unlock() +} + +// Preconditions: filesystem.mu must be locked for writing. +func (dir *directory) removeChildLocked(child *dentry) { + delete(dir.childMap, child.name) + atomic.AddInt64(&dir.numChildren, -1) + dir.iterMu.Lock() + dir.childList.Remove(child) + dir.iterMu.Unlock() } type directoryFD struct { fileDescription vfs.DirectoryFileDescriptionDefaultImpl - // Protected by filesystem.mu. + // Protected by directory.iterMu. iter *dentry off int64 } @@ -51,11 +93,10 @@ type directoryFD struct { // Release implements vfs.FileDescriptionImpl.Release. func (fd *directoryFD) Release() { if fd.iter != nil { - fs := fd.filesystem() dir := fd.inode().impl.(*directory) - fs.mu.Lock() + dir.iterMu.Lock() dir.childList.Remove(fd.iter) - fs.mu.Unlock() + dir.iterMu.Unlock() fd.iter = nil } } @@ -63,10 +104,13 @@ func (fd *directoryFD) Release() { // IterDirents implements vfs.FileDescriptionImpl.IterDirents. func (fd *directoryFD) IterDirents(ctx context.Context, cb vfs.IterDirentsCallback) error { fs := fd.filesystem() - vfsd := fd.vfsfd.VirtualDentry().Dentry() + dir := fd.inode().impl.(*directory) - fs.mu.Lock() - defer fs.mu.Unlock() + // fs.mu is required to read d.parent and dentry.name. + fs.mu.RLock() + defer fs.mu.RUnlock() + dir.iterMu.Lock() + defer dir.iterMu.Unlock() fd.inode().touchAtime(fd.vfsfd.Mount()) @@ -74,15 +118,16 @@ func (fd *directoryFD) IterDirents(ctx context.Context, cb vfs.IterDirentsCallba if err := cb.Handle(vfs.Dirent{ Name: ".", Type: linux.DT_DIR, - Ino: vfsd.Impl().(*dentry).inode.ino, + Ino: dir.inode.ino, NextOff: 1, }); err != nil { return err } fd.off++ } + if fd.off == 1 { - parentInode := vfsd.ParentOrSelf().Impl().(*dentry).inode + parentInode := genericParentOrSelf(&dir.dentry).inode if err := cb.Handle(vfs.Dirent{ Name: "..", Type: parentInode.direntType(), @@ -94,7 +139,6 @@ func (fd *directoryFD) IterDirents(ctx context.Context, cb vfs.IterDirentsCallba fd.off++ } - dir := vfsd.Impl().(*dentry).inode.impl.(*directory) var child *dentry if fd.iter == nil { // Start iteration at the beginning of dir. @@ -109,7 +153,7 @@ func (fd *directoryFD) IterDirents(ctx context.Context, cb vfs.IterDirentsCallba // Skip other directoryFD iterators. if child.inode != nil { if err := cb.Handle(vfs.Dirent{ - Name: child.vfsd.Name(), + Name: child.name, Type: child.inode.direntType(), Ino: child.inode.ino, NextOff: fd.off + 1, @@ -127,9 +171,9 @@ func (fd *directoryFD) IterDirents(ctx context.Context, cb vfs.IterDirentsCallba // Seek implements vfs.FileDescriptionImpl.Seek. func (fd *directoryFD) Seek(ctx context.Context, offset int64, whence int32) (int64, error) { - fs := fd.filesystem() - fs.mu.Lock() - defer fs.mu.Unlock() + dir := fd.inode().impl.(*directory) + dir.iterMu.Lock() + defer dir.iterMu.Unlock() switch whence { case linux.SEEK_SET: @@ -157,8 +201,6 @@ func (fd *directoryFD) Seek(ctx context.Context, offset int64, whence int32) (in remChildren = offset - 2 } - dir := fd.inode().impl.(*directory) - // Ensure that fd.iter exists and is not linked into dir.childList. if fd.iter == nil { fd.iter = &dentry{} diff --git a/pkg/sentry/fsimpl/tmpfs/filesystem.go b/pkg/sentry/fsimpl/tmpfs/filesystem.go index 452c4e2e0..5b62f9ebb 100644 --- a/pkg/sentry/fsimpl/tmpfs/filesystem.go +++ b/pkg/sentry/fsimpl/tmpfs/filesystem.go @@ -39,27 +39,43 @@ func (fs *filesystem) Sync(ctx context.Context) error { // // Preconditions: filesystem.mu must be locked. !rp.Done(). func stepLocked(rp *vfs.ResolvingPath, d *dentry) (*dentry, error) { - if !d.inode.isDir() { + dir, ok := d.inode.impl.(*directory) + if !ok { return nil, syserror.ENOTDIR } if err := d.inode.checkPermissions(rp.Credentials(), vfs.MayExec); err != nil { return nil, err } afterSymlink: - if len(rp.Component()) > linux.NAME_MAX { - return nil, syserror.ENAMETOOLONG + name := rp.Component() + if name == "." { + rp.Advance() + return d, nil } - nextVFSD, err := rp.ResolveComponent(&d.vfsd) - if err != nil { - return nil, err + if name == ".." { + if isRoot, err := rp.CheckRoot(&d.vfsd); err != nil { + return nil, err + } else if isRoot || d.parent == nil { + rp.Advance() + return d, nil + } + if err := rp.CheckMount(&d.parent.vfsd); err != nil { + return nil, err + } + rp.Advance() + return d.parent, nil } - if nextVFSD == nil { - // Since the Dentry tree is the sole source of truth for tmpfs, if it's - // not in the Dentry tree, it doesn't exist. + if len(name) > linux.NAME_MAX { + return nil, syserror.ENAMETOOLONG + } + child, ok := dir.childMap[name] + if !ok { return nil, syserror.ENOENT } - next := nextVFSD.Impl().(*dentry) - if symlink, ok := next.inode.impl.(*symlink); ok && rp.ShouldFollowSymlink() { + if err := rp.CheckMount(&child.vfsd); err != nil { + return nil, err + } + if symlink, ok := child.inode.impl.(*symlink); ok && rp.ShouldFollowSymlink() { // TODO(gvisor.dev/issue/1197): Symlink traversals updates // access time. if err := rp.HandleSymlink(symlink.target); err != nil { @@ -68,7 +84,7 @@ afterSymlink: goto afterSymlink // don't check the current directory again } rp.Advance() - return next, nil + return child, nil } // walkParentDirLocked resolves all but the last path component of rp to an @@ -80,7 +96,7 @@ afterSymlink: // fs/namei.c:path_parentat(). // // Preconditions: filesystem.mu must be locked. !rp.Done(). -func walkParentDirLocked(rp *vfs.ResolvingPath, d *dentry) (*dentry, error) { +func walkParentDirLocked(rp *vfs.ResolvingPath, d *dentry) (*directory, error) { for !rp.Final() { next, err := stepLocked(rp, d) if err != nil { @@ -88,10 +104,11 @@ func walkParentDirLocked(rp *vfs.ResolvingPath, d *dentry) (*dentry, error) { } d = next } - if !d.inode.isDir() { + dir, ok := d.inode.impl.(*directory) + if !ok { return nil, syserror.ENOTDIR } - return d, nil + return dir, nil } // resolveLocked resolves rp to an existing file. @@ -122,14 +139,14 @@ func resolveLocked(rp *vfs.ResolvingPath) (*dentry, error) { // // Preconditions: !rp.Done(). For the final path component in rp, // !rp.ShouldFollowSymlink(). -func (fs *filesystem) doCreateAt(rp *vfs.ResolvingPath, dir bool, create func(parent *dentry, name string) error) error { +func (fs *filesystem) doCreateAt(rp *vfs.ResolvingPath, dir bool, create func(parentDir *directory, name string) error) error { fs.mu.Lock() defer fs.mu.Unlock() - parent, err := walkParentDirLocked(rp, rp.Start().Impl().(*dentry)) + parentDir, err := walkParentDirLocked(rp, rp.Start().Impl().(*dentry)) if err != nil { return err } - if err := parent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec); err != nil { + if err := parentDir.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec); err != nil { return err } name := rp.Component() @@ -139,19 +156,15 @@ func (fs *filesystem) doCreateAt(rp *vfs.ResolvingPath, dir bool, create func(pa if len(name) > linux.NAME_MAX { return syserror.ENAMETOOLONG } - // Call parent.vfsd.Child() instead of stepLocked() or rp.ResolveChild(), - // because if the child exists we want to return EEXIST immediately instead - // of attempting symlink/mount traversal. - if parent.vfsd.Child(name) != nil { + if _, ok := parentDir.childMap[name]; ok { return syserror.EEXIST } if !dir && rp.MustBeDir() { return syserror.ENOENT } - // In tmpfs, the only way to cause a dentry to be disowned is by removing - // it from the filesystem, so this check is equivalent to checking if - // parent has been removed. - if parent.vfsd.IsDisowned() { + // tmpfs never calls VFS.InvalidateDentry(), so parentDir.dentry can only + // be dead if it was deleted. + if parentDir.dentry.vfsd.IsDead() { return syserror.ENOENT } mnt := rp.Mount() @@ -159,10 +172,10 @@ func (fs *filesystem) doCreateAt(rp *vfs.ResolvingPath, dir bool, create func(pa return err } defer mnt.EndWrite() - if err := create(parent, name); err != nil { + if err := create(parentDir, name); err != nil { return err } - parent.inode.touchCMtime() + parentDir.inode.touchCMtime() return nil } @@ -201,17 +214,17 @@ func (fs *filesystem) GetDentryAt(ctx context.Context, rp *vfs.ResolvingPath, op func (fs *filesystem) GetParentDentryAt(ctx context.Context, rp *vfs.ResolvingPath) (*vfs.Dentry, error) { fs.mu.RLock() defer fs.mu.RUnlock() - d, err := walkParentDirLocked(rp, rp.Start().Impl().(*dentry)) + dir, err := walkParentDirLocked(rp, rp.Start().Impl().(*dentry)) if err != nil { return nil, err } - d.IncRef() - return &d.vfsd, nil + dir.dentry.IncRef() + return &dir.dentry.vfsd, nil } // LinkAt implements vfs.FilesystemImpl.LinkAt. func (fs *filesystem) LinkAt(ctx context.Context, rp *vfs.ResolvingPath, vd vfs.VirtualDentry) error { - return fs.doCreateAt(rp, false /* dir */, func(parent *dentry, name string) error { + return fs.doCreateAt(rp, false /* dir */, func(parentDir *directory, name string) error { if rp.Mount() != vd.Mount() { return syserror.EXDEV } @@ -226,30 +239,27 @@ func (fs *filesystem) LinkAt(ctx context.Context, rp *vfs.ResolvingPath, vd vfs. return syserror.EMLINK } d.inode.incLinksLocked() - child := fs.newDentry(d.inode) - parent.vfsd.InsertChild(&child.vfsd, name) - parent.inode.impl.(*directory).childList.PushBack(child) + parentDir.insertChildLocked(fs.newDentry(d.inode), name) return nil }) } // MkdirAt implements vfs.FilesystemImpl.MkdirAt. func (fs *filesystem) MkdirAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.MkdirOptions) error { - return fs.doCreateAt(rp, true /* dir */, func(parent *dentry, name string) error { - if parent.inode.nlink == maxLinks { + return fs.doCreateAt(rp, true /* dir */, func(parentDir *directory, name string) error { + if parentDir.inode.nlink == maxLinks { return syserror.EMLINK } - parent.inode.incLinksLocked() // from child's ".." - child := fs.newDentry(fs.newDirectory(rp.Credentials(), opts.Mode)) - parent.vfsd.InsertChild(&child.vfsd, name) - parent.inode.impl.(*directory).childList.PushBack(child) + parentDir.inode.incLinksLocked() // from child's ".." + childDir := fs.newDirectory(rp.Credentials(), opts.Mode) + parentDir.insertChildLocked(&childDir.dentry, name) return nil }) } // MknodAt implements vfs.FilesystemImpl.MknodAt. func (fs *filesystem) MknodAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.MknodOptions) error { - return fs.doCreateAt(rp, false /* dir */, func(parent *dentry, name string) error { + return fs.doCreateAt(rp, false /* dir */, func(parentDir *directory, name string) error { var childInode *inode switch opts.Mode.FileType() { case 0, linux.S_IFREG: @@ -266,8 +276,7 @@ func (fs *filesystem) MknodAt(ctx context.Context, rp *vfs.ResolvingPath, opts v return syserror.EINVAL } child := fs.newDentry(childInode) - parent.vfsd.InsertChild(&child.vfsd, name) - parent.inode.impl.(*directory).childList.PushBack(child) + parentDir.insertChildLocked(child, name) return nil }) } @@ -306,12 +315,12 @@ func (fs *filesystem) OpenAt(ctx context.Context, rp *vfs.ResolvingPath, opts vf return start.open(ctx, rp, &opts, false /* afterCreate */) } afterTrailingSymlink: - parent, err := walkParentDirLocked(rp, start) + parentDir, err := walkParentDirLocked(rp, start) if err != nil { return nil, err } // Check for search permission in the parent directory. - if err := parent.inode.checkPermissions(rp.Credentials(), vfs.MayExec); err != nil { + if err := parentDir.inode.checkPermissions(rp.Credentials(), vfs.MayExec); err != nil { return nil, err } // Reject attempts to open directories with O_CREAT. @@ -322,11 +331,14 @@ afterTrailingSymlink: if name == "." || name == ".." { return nil, syserror.EISDIR } + if len(name) > linux.NAME_MAX { + return nil, syserror.ENAMETOOLONG + } // Determine whether or not we need to create a file. - child, err := stepLocked(rp, parent) - if err == syserror.ENOENT { + child, ok := parentDir.childMap[name] + if !ok { // Already checked for searchability above; now check for writability. - if err := parent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite); err != nil { + if err := parentDir.inode.checkPermissions(rp.Credentials(), vfs.MayWrite); err != nil { return nil, err } if err := rp.Mount().CheckBeginWrite(); err != nil { @@ -335,21 +347,26 @@ afterTrailingSymlink: defer rp.Mount().EndWrite() // Create and open the child. child := fs.newDentry(fs.newRegularFile(rp.Credentials(), opts.Mode)) - parent.vfsd.InsertChild(&child.vfsd, name) - parent.inode.impl.(*directory).childList.PushBack(child) + parentDir.insertChildLocked(child, name) fd, err := child.open(ctx, rp, &opts, true) if err != nil { return nil, err } - parent.inode.touchCMtime() + parentDir.inode.touchCMtime() return fd, nil } - if err != nil { + // Is the file mounted over? + if err := rp.CheckMount(&child.vfsd); err != nil { return nil, err } // Do we need to resolve a trailing symlink? - if !rp.Done() { - start = parent + if symlink, ok := child.inode.impl.(*symlink); ok && rp.ShouldFollowSymlink() { + // TODO(gvisor.dev/issue/1197): Symlink traversals updates + // access time. + if err := rp.HandleSymlink(symlink.target); err != nil { + return nil, err + } + start = &parentDir.dentry goto afterTrailingSymlink } // Open existing file. @@ -428,7 +445,7 @@ func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa // Resolve newParent first to verify that it's on this Mount. fs.mu.Lock() defer fs.mu.Unlock() - newParent, err := walkParentDirLocked(rp, rp.Start().Impl().(*dentry)) + newParentDir, err := walkParentDirLocked(rp, rp.Start().Impl().(*dentry)) if err != nil { return err } @@ -445,23 +462,22 @@ func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa } defer mnt.EndWrite() - oldParent := oldParentVD.Dentry().Impl().(*dentry) - if err := oldParent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec); err != nil { + oldParentDir := oldParentVD.Dentry().Impl().(*dentry).inode.impl.(*directory) + if err := oldParentDir.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec); err != nil { return err } - // Call vfs.Dentry.Child() instead of stepLocked() or rp.ResolveChild(), - // because if the existing child is a symlink or mount point then we want - // to rename over it rather than follow it. - renamedVFSD := oldParent.vfsd.Child(oldName) - if renamedVFSD == nil { + renamed, ok := oldParentDir.childMap[oldName] + if !ok { return syserror.ENOENT } - renamed := renamedVFSD.Impl().(*dentry) + // Note that we don't need to call rp.CheckMount(), since if renamed is a + // mount point then we want to rename the mount point, not anything in the + // mounted filesystem. if renamed.inode.isDir() { - if renamed == newParent || renamedVFSD.IsAncestorOf(&newParent.vfsd) { + if renamed == &newParentDir.dentry || genericIsAncestorDentry(renamed, &newParentDir.dentry) { return syserror.EINVAL } - if oldParent != newParent { + if oldParentDir != newParentDir { // Writability is needed to change renamed's "..". if err := renamed.inode.checkPermissions(rp.Credentials(), vfs.MayWrite); err != nil { return err @@ -473,18 +489,17 @@ func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa } } - if err := newParent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec); err != nil { + if err := newParentDir.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec); err != nil { return err } - replacedVFSD := newParent.vfsd.Child(newName) - var replaced *dentry - if replacedVFSD != nil { - replaced = replacedVFSD.Impl().(*dentry) - if replaced.inode.isDir() { + replaced, ok := newParentDir.childMap[newName] + if ok { + replacedDir, ok := replaced.inode.impl.(*directory) + if ok { if !renamed.inode.isDir() { return syserror.EISDIR } - if replaced.vfsd.HasChildren() { + if len(replacedDir.childMap) != 0 { return syserror.ENOTEMPTY } } else { @@ -496,11 +511,13 @@ func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa } } } else { - if renamed.inode.isDir() && newParent.inode.nlink == maxLinks { + if renamed.inode.isDir() && newParentDir.inode.nlink == maxLinks { return syserror.EMLINK } } - if newParent.vfsd.IsDisowned() { + // tmpfs never calls VFS.InvalidateDentry(), so newParentDir.dentry can + // only be dead if it was deleted. + if newParentDir.dentry.vfsd.IsDead() { return syserror.ENOENT } @@ -508,36 +525,38 @@ func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa // simplicity, under the assumption that applications are not intentionally // doing noop renames expecting them to succeed where non-noop renames // would fail. - if renamedVFSD == replacedVFSD { + if renamed == replaced { return nil } vfsObj := rp.VirtualFilesystem() - oldParentDir := oldParent.inode.impl.(*directory) - newParentDir := newParent.inode.impl.(*directory) mntns := vfs.MountNamespaceFromContext(ctx) defer mntns.DecRef() - if err := vfsObj.PrepareRenameDentry(mntns, renamedVFSD, replacedVFSD); err != nil { + var replacedVFSD *vfs.Dentry + if replaced != nil { + replacedVFSD = &replaced.vfsd + } + if err := vfsObj.PrepareRenameDentry(mntns, &renamed.vfsd, replacedVFSD); err != nil { return err } if replaced != nil { - newParentDir.childList.Remove(replaced) + newParentDir.removeChildLocked(replaced) if replaced.inode.isDir() { - newParent.inode.decLinksLocked() // from replaced's ".." + newParentDir.inode.decLinksLocked() // from replaced's ".." } replaced.inode.decLinksLocked() } - oldParentDir.childList.Remove(renamed) - newParentDir.childList.PushBack(renamed) - if renamed.inode.isDir() { - oldParent.inode.decLinksLocked() - newParent.inode.incLinksLocked() + oldParentDir.removeChildLocked(renamed) + newParentDir.insertChildLocked(renamed, newName) + vfsObj.CommitRenameReplaceDentry(&renamed.vfsd, replacedVFSD) + oldParentDir.inode.touchCMtime() + if oldParentDir != newParentDir { + if renamed.inode.isDir() { + oldParentDir.inode.decLinksLocked() + newParentDir.inode.incLinksLocked() + } + newParentDir.inode.touchCMtime() } - oldParent.inode.touchCMtime() - newParent.inode.touchCMtime() renamed.inode.touchCtime() - // TODO(gvisor.dev/issue/1197): Update timestamps and parent directory - // sizes. - vfsObj.CommitRenameReplaceDentry(renamedVFSD, &newParent.vfsd, newName, replacedVFSD) return nil } @@ -545,11 +564,11 @@ func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa func (fs *filesystem) RmdirAt(ctx context.Context, rp *vfs.ResolvingPath) error { fs.mu.Lock() defer fs.mu.Unlock() - parent, err := walkParentDirLocked(rp, rp.Start().Impl().(*dentry)) + parentDir, err := walkParentDirLocked(rp, rp.Start().Impl().(*dentry)) if err != nil { return err } - if err := parent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec); err != nil { + if err := parentDir.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec); err != nil { return err } name := rp.Component() @@ -559,15 +578,15 @@ func (fs *filesystem) RmdirAt(ctx context.Context, rp *vfs.ResolvingPath) error if name == ".." { return syserror.ENOTEMPTY } - childVFSD := parent.vfsd.Child(name) - if childVFSD == nil { + child, ok := parentDir.childMap[name] + if !ok { return syserror.ENOENT } - child := childVFSD.Impl().(*dentry) - if !child.inode.isDir() { + childDir, ok := child.inode.impl.(*directory) + if !ok { return syserror.ENOTDIR } - if childVFSD.HasChildren() { + if len(childDir.childMap) != 0 { return syserror.ENOTEMPTY } mnt := rp.Mount() @@ -578,14 +597,14 @@ func (fs *filesystem) RmdirAt(ctx context.Context, rp *vfs.ResolvingPath) error vfsObj := rp.VirtualFilesystem() mntns := vfs.MountNamespaceFromContext(ctx) defer mntns.DecRef() - if err := vfsObj.PrepareDeleteDentry(mntns, childVFSD); err != nil { + if err := vfsObj.PrepareDeleteDentry(mntns, &child.vfsd); err != nil { return err } - parent.inode.impl.(*directory).childList.Remove(child) - parent.inode.decLinksLocked() // from child's ".." + parentDir.removeChildLocked(child) + parentDir.inode.decLinksLocked() // from child's ".." child.inode.decLinksLocked() - vfsObj.CommitDeleteDentry(childVFSD) - parent.inode.touchCMtime() + vfsObj.CommitDeleteDentry(&child.vfsd) + parentDir.inode.touchCMtime() return nil } @@ -627,10 +646,9 @@ func (fs *filesystem) StatFSAt(ctx context.Context, rp *vfs.ResolvingPath) (linu // SymlinkAt implements vfs.FilesystemImpl.SymlinkAt. func (fs *filesystem) SymlinkAt(ctx context.Context, rp *vfs.ResolvingPath, target string) error { - return fs.doCreateAt(rp, false /* dir */, func(parent *dentry, name string) error { + return fs.doCreateAt(rp, false /* dir */, func(parentDir *directory, name string) error { child := fs.newDentry(fs.newSymlink(rp.Credentials(), target)) - parent.vfsd.InsertChild(&child.vfsd, name) - parent.inode.impl.(*directory).childList.PushBack(child) + parentDir.insertChildLocked(child, name) return nil }) } @@ -639,22 +657,21 @@ func (fs *filesystem) SymlinkAt(ctx context.Context, rp *vfs.ResolvingPath, targ func (fs *filesystem) UnlinkAt(ctx context.Context, rp *vfs.ResolvingPath) error { fs.mu.Lock() defer fs.mu.Unlock() - parent, err := walkParentDirLocked(rp, rp.Start().Impl().(*dentry)) + parentDir, err := walkParentDirLocked(rp, rp.Start().Impl().(*dentry)) if err != nil { return err } - if err := parent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec); err != nil { + if err := parentDir.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec); err != nil { return err } name := rp.Component() if name == "." || name == ".." { return syserror.EISDIR } - childVFSD := parent.vfsd.Child(name) - if childVFSD == nil { + child, ok := parentDir.childMap[name] + if !ok { return syserror.ENOENT } - child := childVFSD.Impl().(*dentry) if child.inode.isDir() { return syserror.EISDIR } @@ -669,13 +686,13 @@ func (fs *filesystem) UnlinkAt(ctx context.Context, rp *vfs.ResolvingPath) error vfsObj := rp.VirtualFilesystem() mntns := vfs.MountNamespaceFromContext(ctx) defer mntns.DecRef() - if err := vfsObj.PrepareDeleteDentry(mntns, childVFSD); err != nil { + if err := vfsObj.PrepareDeleteDentry(mntns, &child.vfsd); err != nil { return err } - parent.inode.impl.(*directory).childList.Remove(child) + parentDir.removeChildLocked(child) child.inode.decLinksLocked() - vfsObj.CommitDeleteDentry(childVFSD) - parent.inode.touchCMtime() + vfsObj.CommitDeleteDentry(&child.vfsd) + parentDir.inode.touchCMtime() return nil } @@ -743,5 +760,5 @@ func (fs *filesystem) RemovexattrAt(ctx context.Context, rp *vfs.ResolvingPath, func (fs *filesystem) PrependPath(ctx context.Context, vfsroot, vd vfs.VirtualDentry, b *fspath.Builder) error { fs.mu.RLock() defer fs.mu.RUnlock() - return vfs.GenericPrependPath(vfsroot, vd, b) + return genericPrependPath(vfsroot, vd.Mount(), vd.Dentry().Impl().(*dentry), b) } diff --git a/pkg/sentry/fsimpl/tmpfs/stat_test.go b/pkg/sentry/fsimpl/tmpfs/stat_test.go index d4f59ee5b..60c2c980e 100644 --- a/pkg/sentry/fsimpl/tmpfs/stat_test.go +++ b/pkg/sentry/fsimpl/tmpfs/stat_test.go @@ -71,9 +71,15 @@ func TestStatAfterCreate(t *testing.T) { t.Errorf("got btime %d, want 0", got.Btime.ToNsec()) } - // Size should be 0. - if got.Size != 0 { - t.Errorf("got size %d, want 0", got.Size) + // Size should be 0 (except for directories, which make up a size + // of 20 per entry, including the "." and ".." entries present in + // otherwise-empty directories). + wantSize := uint64(0) + if typ == "dir" { + wantSize = 40 + } + if got.Size != wantSize { + t.Errorf("got size %d, want %d", got.Size, wantSize) } // Nlink should be 1 for files, 2 for dirs. diff --git a/pkg/sentry/fsimpl/tmpfs/tmpfs.go b/pkg/sentry/fsimpl/tmpfs/tmpfs.go index 82c709b43..efc931468 100644 --- a/pkg/sentry/fsimpl/tmpfs/tmpfs.go +++ b/pkg/sentry/fsimpl/tmpfs/tmpfs.go @@ -12,16 +12,19 @@ // See the License for the specific language governing permissions and // limitations under the License. -// Package tmpfs provides a filesystem implementation that behaves like tmpfs: -// the Dentry tree is the sole source of truth for the state of the filesystem. +// Package tmpfs provides an in-memory filesystem whose contents are +// application-mutable, consistent with Linux's tmpfs. // // Lock order: // // filesystem.mu // inode.mu // regularFileFD.offMu +// *** "memmap.Mappable locks" below this point // regularFile.mapsMu +// *** "memmap.Mappable locks taken by Translate" below this point // regularFile.dataMu +// directory.iterMu package tmpfs import ( @@ -41,6 +44,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/vfs/memxattr" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // Name is the default filesystem name. @@ -112,18 +116,18 @@ func (fstype FilesystemType) GetFilesystem(ctx context.Context, vfsObj *vfs.Virt fs.vfsfs.Init(vfsObj, newFSType, &fs) - var root *inode + var root *dentry switch rootFileType { case linux.S_IFREG: - root = fs.newRegularFile(creds, 0777) + root = fs.newDentry(fs.newRegularFile(creds, 0777)) case linux.S_IFLNK: - root = fs.newSymlink(creds, tmpfsOpts.RootSymlinkTarget) + root = fs.newDentry(fs.newSymlink(creds, tmpfsOpts.RootSymlinkTarget)) case linux.S_IFDIR: - root = fs.newDirectory(creds, 01777) + root = &fs.newDirectory(creds, 01777).dentry default: return nil, nil, fmt.Errorf("invalid tmpfs root file type: %#o", rootFileType) } - return &fs.vfsfs, &fs.newDentry(root).vfsd, nil + return &fs.vfsfs, &root.vfsd, nil } // Release implements vfs.FilesystemImpl.Release. @@ -134,20 +138,29 @@ func (fs *filesystem) Release() { type dentry struct { vfsd vfs.Dentry + // parent is this dentry's parent directory. Each referenced dentry holds a + // reference on parent.dentry. If this dentry is a filesystem root, parent + // is nil. parent is protected by filesystem.mu. + parent *dentry + + // name is the name of this dentry in its parent. If this dentry is a + // filesystem root, name is the empty string. name is protected by + // filesystem.mu. + name string + + // dentryEntry (ugh) links dentries into their parent directory.childList. + dentryEntry + // inode is the inode represented by this dentry. Multiple Dentries may // share a single non-directory inode (with hard links). inode is // immutable. - inode *inode - + // // tmpfs doesn't count references on dentries; because the dentry tree is // the sole source of truth, it is by definition always consistent with the // state of the filesystem. However, it does count references on inodes, // because inode resources are released when all references are dropped. - // (tmpfs doesn't really have resources to release, but we implement - // reference counting because tmpfs regular files will.) - - // dentryEntry (ugh) links dentries into their parent directory.childList. - dentryEntry + // dentry therefore forwards reference counting directly to inode. + inode *inode } func (fs *filesystem) newDentry(inode *inode) *dentry { @@ -207,10 +220,6 @@ type inode struct { ctime int64 // nanoseconds mtime int64 // nanoseconds - // Only meaningful for device special files. - rdevMajor uint32 - rdevMinor uint32 - // Advisory file locks, which lock at the inode level. locks lock.FileLocks @@ -230,7 +239,7 @@ func (i *inode) init(impl interface{}, fs *filesystem, creds *auth.Credentials, i.gid = uint32(creds.EffectiveKGID) i.ino = atomic.AddUint64(&fs.nextInoMinusOne, 1) // Tmpfs creation sets atime, ctime, and mtime to current time. - now := i.clock.Now().Nanoseconds() + now := fs.clock.Now().Nanoseconds() i.atime = now i.ctime = now i.mtime = now @@ -283,14 +292,10 @@ func (i *inode) tryIncRef() bool { func (i *inode) decRef() { if refs := atomic.AddInt64(&i.refs, -1); refs == 0 { if regFile, ok := i.impl.(*regularFile); ok { - // Hold inode.mu and regFile.dataMu while mutating - // size. - i.mu.Lock() - regFile.dataMu.Lock() + // Release memory used by regFile to store data. Since regFile is + // no longer usable, we don't need to grab any locks or update any + // metadata. regFile.data.DropAll(regFile.memFile) - atomic.StoreUint64(®File.size, 0) - regFile.dataMu.Unlock() - i.mu.Unlock() } } else if refs < 0 { panic("tmpfs.inode.decRef() called without holding a reference") @@ -310,15 +315,15 @@ func (i *inode) checkPermissions(creds *auth.Credentials, ats vfs.AccessTypes) e // a concurrent modification), so we do not require holding inode.mu. func (i *inode) statTo(stat *linux.Statx) { stat.Mask = linux.STATX_TYPE | linux.STATX_MODE | linux.STATX_NLINK | - linux.STATX_UID | linux.STATX_GID | linux.STATX_INO | linux.STATX_ATIME | - linux.STATX_BTIME | linux.STATX_CTIME | linux.STATX_MTIME - stat.Blksize = 1 // usermem.PageSize in tmpfs + linux.STATX_UID | linux.STATX_GID | linux.STATX_INO | linux.STATX_SIZE | + linux.STATX_BLOCKS | linux.STATX_ATIME | linux.STATX_CTIME | + linux.STATX_MTIME + stat.Blksize = usermem.PageSize stat.Nlink = atomic.LoadUint32(&i.nlink) stat.UID = atomic.LoadUint32(&i.uid) stat.GID = atomic.LoadUint32(&i.gid) stat.Mode = uint16(atomic.LoadUint32(&i.mode)) stat.Ino = i.ino - // Linux's tmpfs has no concept of btime, so zero-value is returned. stat.Atime = linux.NsecToStatxTimestamp(i.atime) stat.Ctime = linux.NsecToStatxTimestamp(i.ctime) stat.Mtime = linux.NsecToStatxTimestamp(i.mtime) @@ -327,19 +332,22 @@ func (i *inode) statTo(stat *linux.Statx) { case *regularFile: stat.Mask |= linux.STATX_SIZE | linux.STATX_BLOCKS stat.Size = uint64(atomic.LoadUint64(&impl.size)) - // In tmpfs, this will be FileRangeSet.Span() / 512 (but also cached in - // a uint64 accessed using atomic memory operations to avoid taking - // locks). + // TODO(jamieliu): This should be impl.data.Span() / 512, but this is + // too expensive to compute here. Cache it in regularFile. stat.Blocks = allocatedBlocksForSize(stat.Size) + case *directory: + // "20" is mm/shmem.c:BOGO_DIRENT_SIZE. + stat.Size = 20 * (2 + uint64(atomic.LoadInt64(&impl.numChildren))) + // stat.Blocks is 0. case *symlink: - stat.Mask |= linux.STATX_SIZE | linux.STATX_BLOCKS stat.Size = uint64(len(impl.target)) - stat.Blocks = allocatedBlocksForSize(stat.Size) + // stat.Blocks is 0. + case *namedPipe, *socketFile: + // stat.Size and stat.Blocks are 0. case *deviceFile: + // stat.Size and stat.Blocks are 0. stat.RdevMajor = impl.major stat.RdevMinor = impl.minor - case *socketFile, *directory, *namedPipe: - // Nothing to do. default: panic(fmt.Sprintf("unknown inode type: %T", i.impl)) } diff --git a/pkg/sentry/vfs/dentry.go b/pkg/sentry/vfs/dentry.go index 35b208721..8624dbd5d 100644 --- a/pkg/sentry/vfs/dentry.go +++ b/pkg/sentry/vfs/dentry.go @@ -15,34 +15,17 @@ package vfs import ( - "fmt" "sync/atomic" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" ) -// Dentry represents a node in a Filesystem tree which may represent a file. +// Dentry represents a node in a Filesystem tree at which a file exists. // // Dentries are reference-counted. Unless otherwise specified, all Dentry // methods require that a reference is held. // -// A Dentry transitions through up to 3 different states through its lifetime: -// -// - Dentries are initially "independent". Independent Dentries have no parent, -// and consequently no name. -// -// - Dentry.InsertChild() causes an independent Dentry to become a "child" of -// another Dentry. A child node has a parent node, and a name in that parent, -// both of which are mutable by DentryMoveChild(). Each child Dentry's name is -// unique within its parent. -// -// - Dentry.RemoveChild() causes a child Dentry to become "disowned". A -// disowned Dentry can still refer to its former parent and its former name in -// said parent, but the disowned Dentry is no longer reachable from its parent, -// and a new Dentry with the same name may become a child of the parent. (This -// is analogous to a struct dentry being "unhashed" in Linux.) -// // Dentry is loosely analogous to Linux's struct dentry, but: // // - VFS does not associate Dentries with inodes. gVisor interacts primarily @@ -57,9 +40,6 @@ import ( // and/or FileDescriptionImpl methods in gVisor's VFS. Filesystems that do // support inodes may store appropriate state in implementations of DentryImpl. // -// - VFS does not provide synchronization for mutable Dentry fields, other than -// mount-related ones. -// // - VFS does not require that Dentries are instantiated for all paths accessed // through VFS, only those that are tracked beyond the scope of a single // Filesystem operation. This includes file descriptions, mount points, mount @@ -67,6 +47,10 @@ import ( // of Dentries for operations on mutable remote filesystems that can't actually // cache any state in the Dentry. // +// - VFS does not track filesystem structure (i.e. relationships between +// Dentries), since both the relevant state and synchronization are +// filesystem-specific. +// // - For the reasons above, VFS is not directly responsible for managing Dentry // lifetime. Dentry reference counts only indicate the extent to which VFS // requires Dentries to exist; Filesystems may elect to cache or discard @@ -74,36 +58,23 @@ import ( // // +stateify savable type Dentry struct { - // parent is this Dentry's parent in this Filesystem. If this Dentry is - // independent, parent is nil. - parent *Dentry - - // name is this Dentry's name in parent. - name string + // mu synchronizes deletion/invalidation and mounting over this Dentry. + mu sync.Mutex `state:"nosave"` - flags uint32 + // dead is true if the file represented by this Dentry has been deleted (by + // CommitDeleteDentry or CommitRenameReplaceDentry) or invalidated (by + // InvalidateDentry). dead is protected by mu. + dead bool // mounts is the number of Mounts for which this Dentry is Mount.point. // mounts is accessed using atomic memory operations. mounts uint32 - // children are child Dentries. - children map[string]*Dentry - - // mu synchronizes disowning and mounting over this Dentry. - mu sync.Mutex `state:"nosave"` - // impl is the DentryImpl associated with this Dentry. impl is immutable. // This should be the last field in Dentry. impl DentryImpl } -const ( - // dflagsDisownedMask is set in Dentry.flags if the Dentry has been - // disowned. - dflagsDisownedMask = 1 << iota -) - // Init must be called before first use of d. func (d *Dentry) Init(impl DentryImpl) { d.impl = impl @@ -134,20 +105,6 @@ type DentryImpl interface { DecRef() } -// IsDisowned returns true if d is disowned. -func (d *Dentry) IsDisowned() bool { - return atomic.LoadUint32(&d.flags)&dflagsDisownedMask != 0 -} - -// Preconditions: !d.IsDisowned(). -func (d *Dentry) setDisowned() { - atomic.AddUint32(&d.flags, dflagsDisownedMask) -} - -func (d *Dentry) isMounted() bool { - return atomic.LoadUint32(&d.mounts) != 0 -} - // IncRef increments d's reference count. func (d *Dentry) IncRef() { d.impl.IncRef() @@ -164,104 +121,26 @@ func (d *Dentry) DecRef() { d.impl.DecRef() } -// These functions are exported so that filesystem implementations can use -// them. The vfs package, and users of VFS, should not call these functions. -// Unless otherwise specified, these methods require that there are no -// concurrent mutators of d. - -// Name returns d's name in its parent in its owning Filesystem. If d is -// independent, Name returns an empty string. -func (d *Dentry) Name() string { - return d.name -} - -// Parent returns d's parent in its owning Filesystem. It does not take a -// reference on the returned Dentry. If d is independent, Parent returns nil. -func (d *Dentry) Parent() *Dentry { - return d.parent -} - -// ParentOrSelf is equivalent to Parent, but returns d if d is independent. -func (d *Dentry) ParentOrSelf() *Dentry { - if d.parent == nil { - return d - } - return d.parent -} - -// Child returns d's child with the given name in its owning Filesystem. It -// does not take a reference on the returned Dentry. If no such child exists, -// Child returns nil. -func (d *Dentry) Child(name string) *Dentry { - return d.children[name] -} - -// HasChildren returns true if d has any children. -func (d *Dentry) HasChildren() bool { - return len(d.children) != 0 -} - -// Children returns a map containing all of d's children. -func (d *Dentry) Children() map[string]*Dentry { - if !d.HasChildren() { - return nil - } - m := make(map[string]*Dentry) - for name, child := range d.children { - m[name] = child - } - return m +// IsDead returns true if d has been deleted or invalidated by its owning +// filesystem. +func (d *Dentry) IsDead() bool { + d.mu.Lock() + defer d.mu.Unlock() + return d.dead } -// InsertChild makes child a child of d with the given name. -// -// InsertChild is a mutator of d and child. -// -// Preconditions: child must be an independent Dentry. d and child must be from -// the same Filesystem. d must not already have a child with the given name. -func (d *Dentry) InsertChild(child *Dentry, name string) { - if checkInvariants { - if _, ok := d.children[name]; ok { - panic(fmt.Sprintf("parent already contains a child named %q", name)) - } - if child.parent != nil || child.name != "" { - panic(fmt.Sprintf("child is not independent: parent = %v, name = %q", child.parent, child.name)) - } - } - if d.children == nil { - d.children = make(map[string]*Dentry) - } - d.children[name] = child - child.parent = d - child.name = name +func (d *Dentry) isMounted() bool { + return atomic.LoadUint32(&d.mounts) != 0 } -// IsAncestorOf returns true if d is an ancestor of d2; that is, d is either -// d2's parent or an ancestor of d2's parent. -func (d *Dentry) IsAncestorOf(d2 *Dentry) bool { - for d2.parent != nil { - if d2.parent == d { - return true - } - d2 = d2.parent - } - return false -} +// The following functions are exported so that filesystem implementations can +// use them. The vfs package, and users of VFS, should not call these +// functions. // PrepareDeleteDentry must be called before attempting to delete the file // represented by d. If PrepareDeleteDentry succeeds, the caller must call // AbortDeleteDentry or CommitDeleteDentry depending on the deletion's outcome. -// -// Preconditions: d is a child Dentry. func (vfs *VirtualFilesystem) PrepareDeleteDentry(mntns *MountNamespace, d *Dentry) error { - if checkInvariants { - if d.parent == nil { - panic("d is independent") - } - if d.IsDisowned() { - panic("d is already disowned") - } - } vfs.mountMu.Lock() if mntns.mountpoints[d] != 0 { vfs.mountMu.Unlock() @@ -280,42 +159,27 @@ func (vfs *VirtualFilesystem) AbortDeleteDentry(d *Dentry) { d.mu.Unlock() } -// CommitDeleteDentry must be called after the file represented by d is -// deleted, and causes d to become disowned. -// -// CommitDeleteDentry is a mutator of d and d.Parent(). -// -// Preconditions: PrepareDeleteDentry was previously called on d. +// CommitDeleteDentry must be called after PrepareDeleteDentry if the deletion +// succeeds. func (vfs *VirtualFilesystem) CommitDeleteDentry(d *Dentry) { - if d.parent != nil { - delete(d.parent.children, d.name) - } - d.setDisowned() + d.dead = true d.mu.Unlock() if d.isMounted() { - vfs.forgetDisownedMountpoint(d) + vfs.forgetDeadMountpoint(d) } } -// ForceDeleteDentry causes d to become disowned. It should only be used in -// cases where VFS has no ability to stop the deletion (e.g. d represents the -// local state of a file on a remote filesystem on which the file has already -// been deleted). -// -// ForceDeleteDentry is a mutator of d and d.Parent(). -// -// Preconditions: d is a child Dentry. -func (vfs *VirtualFilesystem) ForceDeleteDentry(d *Dentry) { - if checkInvariants { - if d.parent == nil { - panic("d is independent") - } - if d.IsDisowned() { - panic("d is already disowned") - } - } +// InvalidateDentry is called when d ceases to represent the file it formerly +// did for reasons outside of VFS' control (e.g. d represents the local state +// of a file on a remote filesystem on which the file has already been +// deleted). +func (vfs *VirtualFilesystem) InvalidateDentry(d *Dentry) { d.mu.Lock() - vfs.CommitDeleteDentry(d) + d.dead = true + d.mu.Unlock() + if d.isMounted() { + vfs.forgetDeadMountpoint(d) + } } // PrepareRenameDentry must be called before attempting to rename the file @@ -324,25 +188,9 @@ func (vfs *VirtualFilesystem) ForceDeleteDentry(d *Dentry) { // caller must call AbortRenameDentry, CommitRenameReplaceDentry, or // CommitRenameExchangeDentry depending on the rename's outcome. // -// Preconditions: from is a child Dentry. If to is not nil, it must be a child -// Dentry from the same Filesystem. from != to. +// Preconditions: If to is not nil, it must be a child Dentry from the same +// Filesystem. from != to. func (vfs *VirtualFilesystem) PrepareRenameDentry(mntns *MountNamespace, from, to *Dentry) error { - if checkInvariants { - if from.parent == nil { - panic("from is independent") - } - if from.IsDisowned() { - panic("from is already disowned") - } - if to != nil { - if to.parent == nil { - panic("to is independent") - } - if to.IsDisowned() { - panic("to is already disowned") - } - } - } vfs.mountMu.Lock() if mntns.mountpoints[from] != 0 { vfs.mountMu.Unlock() @@ -376,24 +224,14 @@ func (vfs *VirtualFilesystem) AbortRenameDentry(from, to *Dentry) { // is renamed without RENAME_EXCHANGE. If to is not nil, it represents the file // that was replaced by from. // -// CommitRenameReplaceDentry is a mutator of from, to, from.Parent(), and -// to.Parent(). -// // Preconditions: PrepareRenameDentry was previously called on from and to. -// newParent.Child(newName) == to. -func (vfs *VirtualFilesystem) CommitRenameReplaceDentry(from, newParent *Dentry, newName string, to *Dentry) { - if newParent.children == nil { - newParent.children = make(map[string]*Dentry) - } - newParent.children[newName] = from - from.parent = newParent - from.name = newName +func (vfs *VirtualFilesystem) CommitRenameReplaceDentry(from, to *Dentry) { from.mu.Unlock() if to != nil { - to.setDisowned() + to.dead = true to.mu.Unlock() if to.isMounted() { - vfs.forgetDisownedMountpoint(to) + vfs.forgetDeadMountpoint(to) } } } @@ -401,25 +239,18 @@ func (vfs *VirtualFilesystem) CommitRenameReplaceDentry(from, newParent *Dentry, // CommitRenameExchangeDentry must be called after the files represented by // from and to are exchanged by rename(RENAME_EXCHANGE). // -// CommitRenameExchangeDentry is a mutator of from, to, from.Parent(), and -// to.Parent(). -// // Preconditions: PrepareRenameDentry was previously called on from and to. func (vfs *VirtualFilesystem) CommitRenameExchangeDentry(from, to *Dentry) { - from.parent, to.parent = to.parent, from.parent - from.name, to.name = to.name, from.name - from.parent.children[from.name] = from - to.parent.children[to.name] = to from.mu.Unlock() to.mu.Unlock() } -// forgetDisownedMountpoint is called when a mount point is deleted to umount -// all mounts using it in all other mount namespaces. +// forgetDeadMountpoint is called when a mount point is deleted or invalidated +// to umount all mounts using it in all other mount namespaces. // -// forgetDisownedMountpoint is analogous to Linux's +// forgetDeadMountpoint is analogous to Linux's // fs/namespace.c:__detach_mounts(). -func (vfs *VirtualFilesystem) forgetDisownedMountpoint(d *Dentry) { +func (vfs *VirtualFilesystem) forgetDeadMountpoint(d *Dentry) { var ( vdsToDecRef []VirtualDentry mountsToDecRef []*Mount diff --git a/pkg/sentry/vfs/file_description.go b/pkg/sentry/vfs/file_description.go index 5976b5ccd..15cc091e2 100644 --- a/pkg/sentry/vfs/file_description.go +++ b/pkg/sentry/vfs/file_description.go @@ -127,7 +127,8 @@ func (fd *FileDescription) Init(impl FileDescriptionImpl, statusFlags uint32, mn mount: mnt, dentry: d, } - fd.vd.IncRef() + mnt.IncRef() + d.IncRef() fd.opts = *opts fd.readable = MayReadFileWithOpenFlags(statusFlags) fd.writable = writable diff --git a/pkg/sentry/vfs/filesystem.go b/pkg/sentry/vfs/filesystem.go index a537a29d1..74577bc2f 100644 --- a/pkg/sentry/vfs/filesystem.go +++ b/pkg/sentry/vfs/filesystem.go @@ -346,7 +346,10 @@ type FilesystemImpl interface { // ENOTEMPTY. // // Preconditions: !rp.Done(). For the final path component in rp, - // !rp.ShouldFollowSymlink(). oldName is not "." or "..". + // !rp.ShouldFollowSymlink(). oldParentVD.Dentry() was obtained from a + // previous call to + // oldParentVD.Mount().Filesystem().Impl().GetParentDentryAt(). oldName is + // not "." or "..". // // Postconditions: If RenameAt returns an error returned by // ResolvingPath.Resolve*(), then !rp.Done(). diff --git a/pkg/sentry/vfs/filesystem_impl_util.go b/pkg/sentry/vfs/filesystem_impl_util.go index 7315a588e..465e610e0 100644 --- a/pkg/sentry/vfs/filesystem_impl_util.go +++ b/pkg/sentry/vfs/filesystem_impl_util.go @@ -16,8 +16,6 @@ package vfs import ( "strings" - - "gvisor.dev/gvisor/pkg/fspath" ) // GenericParseMountOptions parses a comma-separated list of options of the @@ -43,27 +41,3 @@ func GenericParseMountOptions(str string) map[string]string { } return m } - -// GenericPrependPath may be used by implementations of -// FilesystemImpl.PrependPath() for which a single statically-determined lock -// or set of locks is sufficient to ensure its preconditions (as opposed to -// e.g. per-Dentry locks). -// -// Preconditions: Dentry.Name() and Dentry.Parent() must be held constant for -// vd.Dentry() and all of its ancestors. -func GenericPrependPath(vfsroot, vd VirtualDentry, b *fspath.Builder) error { - mnt, d := vd.mount, vd.dentry - for { - if mnt == vfsroot.mount && d == vfsroot.dentry { - return PrependPathAtVFSRootError{} - } - if d == mnt.root { - return nil - } - if d.parent == nil { - return PrependPathAtNonMountRootError{} - } - b.PrependComponent(d.name) - d = d.parent - } -} diff --git a/pkg/sentry/vfs/genericfstree/BUILD b/pkg/sentry/vfs/genericfstree/BUILD new file mode 100644 index 000000000..d8fd92677 --- /dev/null +++ b/pkg/sentry/vfs/genericfstree/BUILD @@ -0,0 +1,16 @@ +load("//tools/go_generics:defs.bzl", "go_template") + +package( + default_visibility = ["//:sandbox"], + licenses = ["notice"], +) + +go_template( + name = "generic_fstree", + srcs = [ + "genericfstree.go", + ], + types = [ + "Dentry", + ], +) diff --git a/pkg/sentry/vfs/genericfstree/genericfstree.go b/pkg/sentry/vfs/genericfstree/genericfstree.go new file mode 100644 index 000000000..286510195 --- /dev/null +++ b/pkg/sentry/vfs/genericfstree/genericfstree.go @@ -0,0 +1,80 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// Package genericfstree provides tools for implementing vfs.FilesystemImpls +// where a single statically-determined lock or set of locks is sufficient to +// ensure that a Dentry's name and parent are contextually immutable. +// +// Clients using this package must use the go_template_instance rule in +// tools/go_generics/defs.bzl to create an instantiation of this template +// package, providing types to use in place of Dentry. +package genericfstree + +import ( + "gvisor.dev/gvisor/pkg/fspath" + "gvisor.dev/gvisor/pkg/sentry/vfs" +) + +// Dentry is a required type parameter that is a struct with the given fields. +type Dentry struct { + // vfsd is the embedded vfs.Dentry corresponding to this vfs.DentryImpl. + vfsd vfs.Dentry + + // parent is the parent of this Dentry in the filesystem's tree. If this + // Dentry is a filesystem root, parent is nil. + parent *Dentry + + // name is the name of this Dentry in its parent. If this Dentry is a + // filesystem root, name is unspecified. + name string +} + +// IsAncestorDentry returns true if d is an ancestor of d2; that is, d is +// either d2's parent or an ancestor of d2's parent. +func IsAncestorDentry(d, d2 *Dentry) bool { + for { + if d2.parent == d { + return true + } + if d2.parent == d2 { + return false + } + d2 = d2.parent + } +} + +// ParentOrSelf returns d.parent. If d.parent is nil, ParentOrSelf returns d. +func ParentOrSelf(d *Dentry) *Dentry { + if d.parent != nil { + return d.parent + } + return d +} + +// PrependPath is a generic implementation of FilesystemImpl.PrependPath(). +func PrependPath(vfsroot vfs.VirtualDentry, mnt *vfs.Mount, d *Dentry, b *fspath.Builder) error { + for { + if mnt == vfsroot.Mount() && &d.vfsd == vfsroot.Dentry() { + return vfs.PrependPathAtVFSRootError{} + } + if &d.vfsd == mnt.Root() { + return nil + } + if d.parent == nil { + return vfs.PrependPathAtNonMountRootError{} + } + b.PrependComponent(d.name) + d = d.parent + } +} diff --git a/pkg/sentry/vfs/mount.go b/pkg/sentry/vfs/mount.go index f06946103..02850b65c 100644 --- a/pkg/sentry/vfs/mount.go +++ b/pkg/sentry/vfs/mount.go @@ -188,6 +188,7 @@ func (vfs *VirtualFilesystem) MountAt(ctx context.Context, creds *auth.Credentia if err != nil { return err } + // We can't hold vfs.mountMu while calling FilesystemImpl methods due to // lock ordering. vd, err := vfs.GetDentryAt(ctx, creds, target, &GetDentryOptions{}) @@ -199,7 +200,7 @@ func (vfs *VirtualFilesystem) MountAt(ctx context.Context, creds *auth.Credentia vfs.mountMu.Lock() vd.dentry.mu.Lock() for { - if vd.dentry.IsDisowned() { + if vd.dentry.dead { vd.dentry.mu.Unlock() vfs.mountMu.Unlock() vd.DecRef() @@ -665,6 +666,12 @@ func (mnt *Mount) submountsLocked() []*Mount { return mounts } +// Root returns the mount's root. It does not take a reference on the returned +// Dentry. +func (mnt *Mount) Root() *Dentry { + return mnt.root +} + // Root returns mntns' root. A reference is taken on the returned // VirtualDentry. func (mntns *MountNamespace) Root() VirtualDentry { diff --git a/pkg/sentry/vfs/pathname.go b/pkg/sentry/vfs/pathname.go index f21a88034..cd78d66bc 100644 --- a/pkg/sentry/vfs/pathname.go +++ b/pkg/sentry/vfs/pathname.go @@ -58,7 +58,7 @@ loop: switch err.(type) { case nil: if vd.mount == vfsroot.mount && vd.mount.root == vfsroot.dentry { - // GenericPrependPath() will have returned + // genericfstree.PrependPath() will have returned // PrependPathAtVFSRootError in this case since it checks // against vfsroot before mnt.root, but other implementations // of FilesystemImpl.PrependPath() may return nil instead. @@ -84,7 +84,7 @@ loop: } } b.PrependByte('/') - if origD.IsDisowned() { + if origD.IsDead() { b.AppendString(" (deleted)") } return b.String(), nil @@ -136,7 +136,7 @@ loop: // PathnameForGetcwd returns an absolute pathname to vd, consistent with // Linux's sys_getcwd(). func (vfs *VirtualFilesystem) PathnameForGetcwd(ctx context.Context, vfsroot, vd VirtualDentry) (string, error) { - if vd.dentry.IsDisowned() { + if vd.dentry.IsDead() { return "", syserror.ENOENT } diff --git a/pkg/sentry/vfs/resolving_path.go b/pkg/sentry/vfs/resolving_path.go index 8f31495da..9d047ff88 100644 --- a/pkg/sentry/vfs/resolving_path.go +++ b/pkg/sentry/vfs/resolving_path.go @@ -29,7 +29,9 @@ import ( // // From the perspective of FilesystemImpl methods, a ResolvingPath represents a // starting Dentry on the associated Filesystem (on which a reference is -// already held) and a stream of path components relative to that Dentry. +// already held), a stream of path components relative to that Dentry, and +// elements of the invoking Context that are commonly required by +// FilesystemImpl methods. // // ResolvingPath is loosely analogous to Linux's struct nameidata. type ResolvingPath struct { @@ -251,18 +253,17 @@ func (rp *ResolvingPath) relpathCommit() { rp.origParts[rp.curPart] = rp.pit } -// ResolveParent returns the VFS parent of d. It does not take a reference on -// the returned Dentry. -// -// Preconditions: There are no concurrent mutators of d. -// -// Postconditions: If the returned error is nil, then the returned Dentry is -// not nil. -func (rp *ResolvingPath) ResolveParent(d *Dentry) (*Dentry, error) { - var parent *Dentry +// CheckRoot is called before resolving the parent of the Dentry d. If the +// Dentry is contextually a VFS root, such that path resolution should treat +// d's parent as itself, CheckRoot returns (true, nil). If the Dentry is the +// root of a non-root mount, such that path resolution should switch to another +// Mount, CheckRoot returns (unspecified, non-nil error). Otherwise, path +// resolution should resolve d's parent normally, and CheckRoot returns (false, +// nil). +func (rp *ResolvingPath) CheckRoot(d *Dentry) (bool, error) { if d == rp.root.dentry && rp.mount == rp.root.mount { - // At contextual VFS root. - parent = d + // At contextual VFS root (due to e.g. chroot(2)). + return true, nil } else if d == rp.mount.root { // At mount root ... vd := rp.vfs.getMountpointAt(rp.mount, rp.root) @@ -270,59 +271,27 @@ func (rp *ResolvingPath) ResolveParent(d *Dentry) (*Dentry, error) { // ... of non-root mount. rp.nextMount = vd.mount rp.nextStart = vd.dentry - return nil, resolveMountRootOrJumpError{} + return false, resolveMountRootOrJumpError{} } // ... of root mount. - parent = d - } else if d.parent == nil { - // At filesystem root. - parent = d - } else { - parent = d.parent + return true, nil } - if parent.isMounted() { - if mnt := rp.vfs.getMountAt(rp.mount, parent); mnt != nil { - rp.nextMount = mnt - return nil, resolveMountPointError{} - } - } - return parent, nil + return false, nil } -// ResolveChild returns the VFS child of d with the given name. It does not -// take a reference on the returned Dentry. If no such child exists, -// ResolveChild returns (nil, nil). -// -// Preconditions: There are no concurrent mutators of d. -func (rp *ResolvingPath) ResolveChild(d *Dentry, name string) (*Dentry, error) { - child := d.children[name] - if child == nil { - return nil, nil +// CheckMount is called after resolving the parent or child of another Dentry +// to d. If d is a mount point, such that path resolution should switch to +// another Mount, CheckMount returns a non-nil error. Otherwise, CheckMount +// returns nil. +func (rp *ResolvingPath) CheckMount(d *Dentry) error { + if !d.isMounted() { + return nil } - if child.isMounted() { - if mnt := rp.vfs.getMountAt(rp.mount, child); mnt != nil { - rp.nextMount = mnt - return nil, resolveMountPointError{} - } - } - return child, nil -} - -// ResolveComponent returns the Dentry reached by starting at d and resolving -// the current path component in the stream represented by rp. It does not -// advance the stream. It does not take a reference on the returned Dentry. If -// no such Dentry exists, ResolveComponent returns (nil, nil). -// -// Preconditions: !rp.Done(). There are no concurrent mutators of d. -func (rp *ResolvingPath) ResolveComponent(d *Dentry) (*Dentry, error) { - switch pc := rp.Component(); pc { - case ".": - return d, nil - case "..": - return rp.ResolveParent(d) - default: - return rp.ResolveChild(d, pc) + if mnt := rp.vfs.getMountAt(rp.mount, d); mnt != nil { + rp.nextMount = mnt + return resolveMountPointError{} } + return nil } // ShouldFollowSymlink returns true if, supposing that the current path -- cgit v1.2.3