diff options
Diffstat (limited to 'pkg/sentry/fsimpl/kernfs')
-rw-r--r-- | pkg/sentry/fsimpl/kernfs/BUILD | 3 | ||||
-rw-r--r-- | pkg/sentry/fsimpl/kernfs/filesystem.go | 63 | ||||
-rw-r--r-- | pkg/sentry/fsimpl/kernfs/inode_impl_util.go | 48 | ||||
-rw-r--r-- | pkg/sentry/fsimpl/kernfs/kernfs.go | 4 | ||||
-rw-r--r-- | pkg/sentry/fsimpl/kernfs/kernfs_test.go | 175 | ||||
-rw-r--r-- | pkg/sentry/fsimpl/kernfs/symlink.go | 21 |
6 files changed, 113 insertions, 201 deletions
diff --git a/pkg/sentry/fsimpl/kernfs/BUILD b/pkg/sentry/fsimpl/kernfs/BUILD index 39c03ee9d..66d409785 100644 --- a/pkg/sentry/fsimpl/kernfs/BUILD +++ b/pkg/sentry/fsimpl/kernfs/BUILD @@ -39,6 +39,7 @@ go_library( "//pkg/sentry/memmap", "//pkg/sentry/usermem", "//pkg/sentry/vfs", + "//pkg/sync", "//pkg/syserror", ], ) @@ -50,9 +51,9 @@ go_test( deps = [ ":kernfs", "//pkg/abi/linux", - "//pkg/fspath", "//pkg/sentry/context", "//pkg/sentry/context/contexttest", + "//pkg/sentry/fsimpl/testutil", "//pkg/sentry/kernel/auth", "//pkg/sentry/usermem", "//pkg/sentry/vfs", diff --git a/pkg/sentry/fsimpl/kernfs/filesystem.go b/pkg/sentry/fsimpl/kernfs/filesystem.go index 79759e0fc..a4600ad47 100644 --- a/pkg/sentry/fsimpl/kernfs/filesystem.go +++ b/pkg/sentry/fsimpl/kernfs/filesystem.go @@ -22,7 +22,6 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/fspath" "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/syserror" ) @@ -40,7 +39,7 @@ func (fs *Filesystem) stepExistingLocked(ctx context.Context, rp *vfs.ResolvingP return nil, syserror.ENOTDIR } // Directory searchable? - if err := d.inode.CheckPermissions(rp.Credentials(), vfs.MayExec); err != nil { + if err := d.inode.CheckPermissions(ctx, rp.Credentials(), vfs.MayExec); err != nil { return nil, err } afterSymlink: @@ -182,8 +181,8 @@ func (fs *Filesystem) walkParentDirLocked(ctx context.Context, rp *vfs.Resolving // // Preconditions: Filesystem.mu must be locked for at least reading. parentInode // == parentVFSD.Impl().(*Dentry).Inode. isDir(parentInode) == true. -func checkCreateLocked(rp *vfs.ResolvingPath, parentVFSD *vfs.Dentry, parentInode Inode) (string, error) { - if err := parentInode.CheckPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec); err != nil { +func checkCreateLocked(ctx context.Context, rp *vfs.ResolvingPath, parentVFSD *vfs.Dentry, parentInode Inode) (string, error) { + if err := parentInode.CheckPermissions(ctx, rp.Credentials(), vfs.MayWrite|vfs.MayExec); err != nil { return "", err } pc := rp.Component() @@ -206,7 +205,7 @@ func checkCreateLocked(rp *vfs.ResolvingPath, parentVFSD *vfs.Dentry, parentInod // checkDeleteLocked checks that the file represented by vfsd may be deleted. // // Preconditions: Filesystem.mu must be locked for at least reading. -func checkDeleteLocked(rp *vfs.ResolvingPath, vfsd *vfs.Dentry) error { +func checkDeleteLocked(ctx context.Context, rp *vfs.ResolvingPath, vfsd *vfs.Dentry) error { parentVFSD := vfsd.Parent() if parentVFSD == nil { return syserror.EBUSY @@ -214,36 +213,12 @@ func checkDeleteLocked(rp *vfs.ResolvingPath, vfsd *vfs.Dentry) error { if parentVFSD.IsDisowned() { return syserror.ENOENT } - if err := parentVFSD.Impl().(*Dentry).inode.CheckPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec); err != nil { + if err := parentVFSD.Impl().(*Dentry).inode.CheckPermissions(ctx, rp.Credentials(), vfs.MayWrite|vfs.MayExec); err != nil { return err } return nil } -// checkRenameLocked checks that a rename operation may be performed on the -// target dentry across the given set of parent directories. The target dentry -// may be nil. -// -// Precondition: isDir(dstInode) == true. -func checkRenameLocked(creds *auth.Credentials, src, dstDir *vfs.Dentry, dstInode Inode) error { - srcDir := src.Parent() - if srcDir == nil { - return syserror.EBUSY - } - if srcDir.IsDisowned() { - return syserror.ENOENT - } - if dstDir.IsDisowned() { - return syserror.ENOENT - } - // Check for creation permissions on dst dir. - if err := dstInode.CheckPermissions(creds, vfs.MayWrite|vfs.MayExec); err != nil { - return err - } - - return nil -} - // Release implements vfs.FilesystemImpl.Release. func (fs *Filesystem) Release() { } @@ -269,7 +244,7 @@ func (fs *Filesystem) GetDentryAt(ctx context.Context, rp *vfs.ResolvingPath, op if !d.isDir() { return nil, syserror.ENOTDIR } - if err := inode.CheckPermissions(rp.Credentials(), vfs.MayExec); err != nil { + if err := inode.CheckPermissions(ctx, rp.Credentials(), vfs.MayExec); err != nil { return nil, err } } @@ -302,7 +277,7 @@ func (fs *Filesystem) LinkAt(ctx context.Context, rp *vfs.ResolvingPath, vd vfs. if err != nil { return err } - pc, err := checkCreateLocked(rp, parentVFSD, parentInode) + pc, err := checkCreateLocked(ctx, rp, parentVFSD, parentInode) if err != nil { return err } @@ -339,7 +314,7 @@ func (fs *Filesystem) MkdirAt(ctx context.Context, rp *vfs.ResolvingPath, opts v if err != nil { return err } - pc, err := checkCreateLocked(rp, parentVFSD, parentInode) + pc, err := checkCreateLocked(ctx, rp, parentVFSD, parentInode) if err != nil { return err } @@ -367,7 +342,7 @@ func (fs *Filesystem) MknodAt(ctx context.Context, rp *vfs.ResolvingPath, opts v if err != nil { return err } - pc, err := checkCreateLocked(rp, parentVFSD, parentInode) + pc, err := checkCreateLocked(ctx, rp, parentVFSD, parentInode) if err != nil { return err } @@ -401,7 +376,7 @@ func (fs *Filesystem) OpenAt(ctx context.Context, rp *vfs.ResolvingPath, opts vf if err != nil { return nil, err } - if err := inode.CheckPermissions(rp.Credentials(), ats); err != nil { + if err := inode.CheckPermissions(ctx, rp.Credentials(), ats); err != nil { return nil, err } return inode.Open(rp, vfsd, opts.Flags) @@ -420,7 +395,7 @@ func (fs *Filesystem) OpenAt(ctx context.Context, rp *vfs.ResolvingPath, opts vf if mustCreate { return nil, syserror.EEXIST } - if err := inode.CheckPermissions(rp.Credentials(), ats); err != nil { + if err := inode.CheckPermissions(ctx, rp.Credentials(), ats); err != nil { return nil, err } return inode.Open(rp, vfsd, opts.Flags) @@ -432,7 +407,7 @@ afterTrailingSymlink: return nil, err } // Check for search permission in the parent directory. - if err := parentInode.CheckPermissions(rp.Credentials(), vfs.MayExec); err != nil { + if err := parentInode.CheckPermissions(ctx, rp.Credentials(), vfs.MayExec); err != nil { return nil, err } // Reject attempts to open directories with O_CREAT. @@ -450,7 +425,7 @@ afterTrailingSymlink: } if childVFSD == nil { // Already checked for searchability above; now check for writability. - if err := parentInode.CheckPermissions(rp.Credentials(), vfs.MayWrite); err != nil { + if err := parentInode.CheckPermissions(ctx, rp.Credentials(), vfs.MayWrite); err != nil { return nil, err } if err := rp.Mount().CheckBeginWrite(); err != nil { @@ -485,7 +460,7 @@ afterTrailingSymlink: goto afterTrailingSymlink } } - if err := childInode.CheckPermissions(rp.Credentials(), ats); err != nil { + if err := childInode.CheckPermissions(ctx, rp.Credentials(), ats); err != nil { return nil, err } return childInode.Open(rp, childVFSD, opts.Flags) @@ -545,13 +520,13 @@ func (fs *Filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa srcVFSD := &src.vfsd // Can we remove the src dentry? - if err := checkDeleteLocked(rp, srcVFSD); err != nil { + if err := checkDeleteLocked(ctx, rp, srcVFSD); err != nil { return err } // Can we create the dst dentry? var dstVFSD *vfs.Dentry - pc, err := checkCreateLocked(rp, dstDirVFSD, dstDirInode) + pc, err := checkCreateLocked(ctx, rp, dstDirVFSD, dstDirInode) switch err { case nil: // Ok, continue with rename as replacement. @@ -607,7 +582,7 @@ func (fs *Filesystem) RmdirAt(ctx context.Context, rp *vfs.ResolvingPath) error return err } defer rp.Mount().EndWrite() - if err := checkDeleteLocked(rp, vfsd); err != nil { + if err := checkDeleteLocked(ctx, rp, vfsd); err != nil { return err } if !vfsd.Impl().(*Dentry).isDir() { @@ -683,7 +658,7 @@ func (fs *Filesystem) SymlinkAt(ctx context.Context, rp *vfs.ResolvingPath, targ if err != nil { return err } - pc, err := checkCreateLocked(rp, parentVFSD, parentInode) + pc, err := checkCreateLocked(ctx, rp, parentVFSD, parentInode) if err != nil { return err } @@ -712,7 +687,7 @@ func (fs *Filesystem) UnlinkAt(ctx context.Context, rp *vfs.ResolvingPath) error return err } defer rp.Mount().EndWrite() - if err := checkDeleteLocked(rp, vfsd); err != nil { + if err := checkDeleteLocked(ctx, rp, vfsd); err != nil { return err } if vfsd.Impl().(*Dentry).isDir() { diff --git a/pkg/sentry/fsimpl/kernfs/inode_impl_util.go b/pkg/sentry/fsimpl/kernfs/inode_impl_util.go index 752e0f659..1700fffd9 100644 --- a/pkg/sentry/fsimpl/kernfs/inode_impl_util.go +++ b/pkg/sentry/fsimpl/kernfs/inode_impl_util.go @@ -16,7 +16,6 @@ package kernfs import ( "fmt" - "sync" "sync/atomic" "gvisor.dev/gvisor/pkg/abi/linux" @@ -24,6 +23,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" ) @@ -262,7 +262,7 @@ func (a *InodeAttrs) SetStat(_ *vfs.Filesystem, opts vfs.SetStatOptions) error { } // CheckPermissions implements Inode.CheckPermissions. -func (a *InodeAttrs) CheckPermissions(creds *auth.Credentials, ats vfs.AccessTypes) error { +func (a *InodeAttrs) CheckPermissions(_ context.Context, creds *auth.Credentials, ats vfs.AccessTypes) error { mode := a.Mode() return vfs.GenericCheckPermissions( creds, @@ -510,3 +510,47 @@ type InodeSymlink struct { func (InodeSymlink) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, flags uint32) (*vfs.FileDescription, error) { return nil, syserror.ELOOP } + +// StaticDirectory is a standard implementation of a directory with static +// contents. +// +// +stateify savable +type StaticDirectory struct { + InodeNotSymlink + InodeDirectoryNoNewChildren + InodeAttrs + InodeNoDynamicLookup + OrderedChildren +} + +var _ Inode = (*StaticDirectory)(nil) + +// NewStaticDir creates a new static directory and returns its dentry. +func NewStaticDir(creds *auth.Credentials, ino uint64, perm linux.FileMode, children map[string]*Dentry) *Dentry { + inode := &StaticDirectory{} + inode.Init(creds, ino, perm) + + dentry := &Dentry{} + dentry.Init(inode) + + inode.OrderedChildren.Init(OrderedChildrenOptions{}) + links := inode.OrderedChildren.Populate(dentry, children) + inode.IncLinks(links) + + return dentry +} + +// Init initializes StaticDirectory. +func (s *StaticDirectory) Init(creds *auth.Credentials, ino uint64, perm linux.FileMode) { + if perm&^linux.PermissionsMask != 0 { + panic(fmt.Sprintf("Only permission mask must be set: %x", perm&linux.PermissionsMask)) + } + s.InodeAttrs.Init(creds, ino, linux.ModeDirectory|perm) +} + +// Open implements kernfs.Inode. +func (s *StaticDirectory) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, flags uint32) (*vfs.FileDescription, error) { + fd := &GenericDirectoryFD{} + fd.Init(rp.Mount(), vfsd, &s.OrderedChildren, flags) + return fd.VFSFileDescription(), nil +} diff --git a/pkg/sentry/fsimpl/kernfs/kernfs.go b/pkg/sentry/fsimpl/kernfs/kernfs.go index d69b299ae..85bcdcc57 100644 --- a/pkg/sentry/fsimpl/kernfs/kernfs.go +++ b/pkg/sentry/fsimpl/kernfs/kernfs.go @@ -53,7 +53,6 @@ package kernfs import ( "fmt" - "sync" "sync/atomic" "gvisor.dev/gvisor/pkg/abi/linux" @@ -61,6 +60,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sync" ) // FilesystemType implements vfs.FilesystemType. @@ -320,7 +320,7 @@ type inodeMetadata interface { // CheckPermissions checks that creds may access this inode for the // requested access type, per the the rules of // fs/namei.c:generic_permission(). - CheckPermissions(creds *auth.Credentials, atx vfs.AccessTypes) error + CheckPermissions(ctx context.Context, creds *auth.Credentials, atx vfs.AccessTypes) error // Mode returns the (struct stat)::st_mode value for this inode. This is // separated from Stat for performance. diff --git a/pkg/sentry/fsimpl/kernfs/kernfs_test.go b/pkg/sentry/fsimpl/kernfs/kernfs_test.go index 4b6b95f5f..a5fdfbde5 100644 --- a/pkg/sentry/fsimpl/kernfs/kernfs_test.go +++ b/pkg/sentry/fsimpl/kernfs/kernfs_test.go @@ -17,17 +17,14 @@ package kernfs_test import ( "bytes" "fmt" - "io" - "runtime" - "sync" "testing" "github.com/google/go-cmp/cmp" "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/fspath" "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/context/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" @@ -41,21 +38,11 @@ const staticFileContent = "This is sample content for a static test file." // filesystem. See newTestSystem. type RootDentryFn func(*auth.Credentials, *filesystem) *kernfs.Dentry -// TestSystem represents the context for a single test. -type TestSystem struct { - t *testing.T - ctx context.Context - creds *auth.Credentials - vfs *vfs.VirtualFilesystem - mns *vfs.MountNamespace - root vfs.VirtualDentry -} - // newTestSystem sets up a minimal environment for running a test, including an // instance of a test filesystem. Tests can control the contents of the // filesystem by providing an appropriate rootFn, which should return a // pre-populated root dentry. -func newTestSystem(t *testing.T, rootFn RootDentryFn) *TestSystem { +func newTestSystem(t *testing.T, rootFn RootDentryFn) *testutil.System { ctx := contexttest.Context(t) creds := auth.CredentialsFromContext(ctx) v := vfs.New() @@ -66,57 +53,7 @@ func newTestSystem(t *testing.T, rootFn RootDentryFn) *TestSystem { if err != nil { t.Fatalf("Failed to create testfs root mount: %v", err) } - - s := &TestSystem{ - t: t, - ctx: ctx, - creds: creds, - vfs: v, - mns: mns, - root: mns.Root(), - } - runtime.SetFinalizer(s, func(s *TestSystem) { s.root.DecRef() }) - return s -} - -// PathOpAtRoot constructs a vfs.PathOperation for a path from the -// root of the test filesystem. -// -// Precondition: path should be relative path. -func (s *TestSystem) PathOpAtRoot(path string) vfs.PathOperation { - return vfs.PathOperation{ - Root: s.root, - Start: s.root, - Path: fspath.Parse(path), - } -} - -// GetDentryOrDie attempts to resolve a dentry referred to by the -// provided path operation. If unsuccessful, the test fails. -func (s *TestSystem) GetDentryOrDie(pop vfs.PathOperation) vfs.VirtualDentry { - vd, err := s.vfs.GetDentryAt(s.ctx, s.creds, &pop, &vfs.GetDentryOptions{}) - if err != nil { - s.t.Fatalf("GetDentryAt(pop:%+v) failed: %v", pop, err) - } - return vd -} - -func (s *TestSystem) ReadToEnd(fd *vfs.FileDescription) (string, error) { - buf := make([]byte, usermem.PageSize) - bufIOSeq := usermem.BytesIOSequence(buf) - opts := vfs.ReadOptions{} - - var content bytes.Buffer - for { - n, err := fd.Impl().Read(s.ctx, bufIOSeq, opts) - if n == 0 || err != nil { - if err == io.EOF { - err = nil - } - return content.String(), err - } - content.Write(buf[:n]) - } + return testutil.NewSystem(ctx, t, v, mns) } type fsType struct { @@ -260,6 +197,7 @@ func TestBasic(t *testing.T) { "file1": fs.newFile(creds, staticFileContent), }) }) + defer sys.Destroy() sys.GetDentryOrDie(sys.PathOpAtRoot("file1")).DecRef() } @@ -269,9 +207,10 @@ func TestMkdirGetDentry(t *testing.T) { "dir1": fs.newDir(creds, 0755, nil), }) }) + defer sys.Destroy() pop := sys.PathOpAtRoot("dir1/a new directory") - if err := sys.vfs.MkdirAt(sys.ctx, sys.creds, &pop, &vfs.MkdirOptions{Mode: 0755}); err != nil { + if err := sys.VFS.MkdirAt(sys.Ctx, sys.Creds, &pop, &vfs.MkdirOptions{Mode: 0755}); err != nil { t.Fatalf("MkdirAt for PathOperation %+v failed: %v", pop, err) } sys.GetDentryOrDie(pop).DecRef() @@ -283,20 +222,21 @@ func TestReadStaticFile(t *testing.T) { "file1": fs.newFile(creds, staticFileContent), }) }) + 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{}) if err != nil { - sys.t.Fatalf("OpenAt for PathOperation %+v failed: %v", pop, err) + t.Fatalf("OpenAt for PathOperation %+v failed: %v", pop, err) } defer fd.DecRef() content, err := sys.ReadToEnd(fd) if err != nil { - sys.t.Fatalf("Read failed: %v", err) + t.Fatalf("Read failed: %v", err) } if diff := cmp.Diff(staticFileContent, content); diff != "" { - sys.t.Fatalf("Read returned unexpected data:\n--- want\n+++ got\n%v", diff) + t.Fatalf("Read returned unexpected data:\n--- want\n+++ got\n%v", diff) } } @@ -306,83 +246,44 @@ func TestCreateNewFileInStaticDir(t *testing.T) { "dir1": fs.newDir(creds, 0755, nil), }) }) + defer sys.Destroy() pop := sys.PathOpAtRoot("dir1/newfile") opts := &vfs.OpenOptions{Flags: linux.O_CREAT | linux.O_EXCL, Mode: defaultMode} - fd, err := sys.vfs.OpenAt(sys.ctx, sys.creds, &pop, opts) + fd, err := sys.VFS.OpenAt(sys.Ctx, sys.Creds, &pop, opts) if err != nil { - sys.t.Fatalf("OpenAt(pop:%+v, opts:%+v) failed: %v", pop, opts, err) + t.Fatalf("OpenAt(pop:%+v, opts:%+v) failed: %v", pop, opts, err) } // 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{}) if err != nil { - sys.t.Fatalf("OpenAt(pop:%+v) = %+v failed: %v", pop, fd, err) + t.Fatalf("OpenAt(pop:%+v) = %+v failed: %v", pop, fd, err) } fd.DecRef() } -// direntCollector provides an implementation for vfs.IterDirentsCallback for -// testing. It simply iterates to the end of a given directory FD and collects -// all dirents emitted by the callback. -type direntCollector struct { - mu sync.Mutex - dirents map[string]vfs.Dirent -} - -// Handle implements vfs.IterDirentsCallback.Handle. -func (d *direntCollector) Handle(dirent vfs.Dirent) bool { - d.mu.Lock() - if d.dirents == nil { - d.dirents = make(map[string]vfs.Dirent) - } - d.dirents[dirent.Name] = dirent - d.mu.Unlock() - return true -} - -// count returns the number of dirents currently in the collector. -func (d *direntCollector) count() int { - d.mu.Lock() - defer d.mu.Unlock() - return len(d.dirents) -} - -// contains checks whether the collector has a dirent with the given name and -// type. -func (d *direntCollector) contains(name string, typ uint8) error { - d.mu.Lock() - defer d.mu.Unlock() - dirent, ok := d.dirents[name] - if !ok { - return fmt.Errorf("No dirent named %q found", name) - } - if dirent.Type != typ { - return fmt.Errorf("Dirent named %q found, but was expecting type %d, got: %+v", name, typ, dirent) - } - return nil -} - func TestDirFDReadWrite(t *testing.T) { sys := newTestSystem(t, func(creds *auth.Credentials, fs *filesystem) *kernfs.Dentry { return fs.newReadonlyDir(creds, 0755, nil) }) + 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{}) if err != nil { - sys.t.Fatalf("OpenAt for PathOperation %+v failed: %v", pop, err) + t.Fatalf("OpenAt for PathOperation %+v failed: %v", pop, err) } defer fd.DecRef() // Read/Write should fail for directory FDs. - if _, err := fd.Read(sys.ctx, usermem.BytesIOSequence([]byte{}), vfs.ReadOptions{}); err != syserror.EISDIR { - sys.t.Fatalf("Read for directory FD failed with unexpected error: %v", err) + 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 { - sys.t.Fatalf("Wrire for directory FD failed with unexpected error: %v", err) + if _, err := fd.Write(sys.Ctx, usermem.BytesIOSequence([]byte{}), vfs.WriteOptions{}); err != syserror.EISDIR { + t.Fatalf("Write for directory FD failed with unexpected error: %v", err) } } @@ -397,30 +298,12 @@ func TestDirFDIterDirents(t *testing.T) { "file1": fs.newFile(creds, staticFileContent), }) }) + defer sys.Destroy() pop := sys.PathOpAtRoot("/") - fd, err := sys.vfs.OpenAt(sys.ctx, sys.creds, &pop, &vfs.OpenOptions{}) - if err != nil { - sys.t.Fatalf("OpenAt for PathOperation %+v failed: %v", pop, err) - } - defer fd.DecRef() - - collector := &direntCollector{} - if err := fd.IterDirents(sys.ctx, collector); err != nil { - sys.t.Fatalf("IterDirent failed: %v", err) - } - - // Root directory should contain ".", ".." and 3 children: - if collector.count() != 5 { - sys.t.Fatalf("IterDirent returned too many dirents") - } - for _, dirName := range []string{".", "..", "dir1", "dir2"} { - if err := collector.contains(dirName, linux.DT_DIR); err != nil { - sys.t.Fatalf("IterDirent had unexpected results: %v", err) - } - } - if err := collector.contains("file1", linux.DT_REG); err != nil { - sys.t.Fatalf("IterDirent had unexpected results: %v", err) - } - + sys.AssertDirectoryContains(&pop, map[string]testutil.DirentType{ + "dir1": linux.DT_DIR, + "dir2": linux.DT_DIR, + "file1": linux.DT_REG, + }) } diff --git a/pkg/sentry/fsimpl/kernfs/symlink.go b/pkg/sentry/fsimpl/kernfs/symlink.go index 068063f4e..f19f12854 100644 --- a/pkg/sentry/fsimpl/kernfs/symlink.go +++ b/pkg/sentry/fsimpl/kernfs/symlink.go @@ -20,7 +20,9 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel/auth" ) -type staticSymlink struct { +// StaticSymlink provides an Inode implementation for symlinks that point to +// a immutable target. +type StaticSymlink struct { InodeAttrs InodeNoopRefCount InodeSymlink @@ -28,18 +30,25 @@ type staticSymlink struct { target string } -var _ Inode = (*staticSymlink)(nil) +var _ Inode = (*StaticSymlink)(nil) // NewStaticSymlink creates a new symlink file pointing to 'target'. -func NewStaticSymlink(creds *auth.Credentials, ino uint64, perm linux.FileMode, target string) *Dentry { - inode := &staticSymlink{target: target} - inode.Init(creds, ino, linux.ModeSymlink|perm) +func NewStaticSymlink(creds *auth.Credentials, ino uint64, target string) *Dentry { + inode := &StaticSymlink{} + inode.Init(creds, ino, target) d := &Dentry{} d.Init(inode) return d } -func (s *staticSymlink) Readlink(_ context.Context) (string, error) { +// Init initializes the instance. +func (s *StaticSymlink) Init(creds *auth.Credentials, ino uint64, target string) { + s.target = target + s.InodeAttrs.Init(creds, ino, linux.ModeSymlink|0777) +} + +// Readlink implements Inode. +func (s *StaticSymlink) Readlink(_ context.Context) (string, error) { return s.target, nil } |