diff options
Diffstat (limited to 'pkg/sentry/fs/proc/sys.go')
-rw-r--r-- | pkg/sentry/fs/proc/sys.go | 116 |
1 files changed, 70 insertions, 46 deletions
diff --git a/pkg/sentry/fs/proc/sys.go b/pkg/sentry/fs/proc/sys.go index 54562508d..ee6b9f262 100644 --- a/pkg/sentry/fs/proc/sys.go +++ b/pkg/sentry/fs/proc/sys.go @@ -22,39 +22,15 @@ import ( "gvisor.googlesource.com/gvisor/pkg/abi/linux" "gvisor.googlesource.com/gvisor/pkg/sentry/context" "gvisor.googlesource.com/gvisor/pkg/sentry/fs" + "gvisor.googlesource.com/gvisor/pkg/sentry/fs/fsutil" "gvisor.googlesource.com/gvisor/pkg/sentry/fs/proc/seqfile" "gvisor.googlesource.com/gvisor/pkg/sentry/fs/ramfs" "gvisor.googlesource.com/gvisor/pkg/sentry/kernel" "gvisor.googlesource.com/gvisor/pkg/sentry/socket/rpcinet" "gvisor.googlesource.com/gvisor/pkg/sentry/usermem" + "gvisor.googlesource.com/gvisor/pkg/waiter" ) -// hostname is a file containing the system hostname. -// -// +stateify savable -type hostname struct { - ramfs.Entry -} - -// DeprecatedPreadv implements fs.InodeOperations.DeprecatedPreadv. -func (hostname) DeprecatedPreadv(ctx context.Context, dst usermem.IOSequence, offset int64) (int64, error) { - utsns := kernel.UTSNamespaceFromContext(ctx) - contents := []byte(utsns.HostName() + "\n") - - if offset >= int64(len(contents)) { - return 0, io.EOF - } - - n, err := dst.CopyOut(ctx, contents[offset:]) - return int64(n), err -} - -func (p *proc) newHostname(ctx context.Context, msrc *fs.MountSource) *fs.Inode { - h := &hostname{} - h.InitEntry(ctx, fs.RootOwner, fs.FilePermsFromMode(0444)) - return newFile(h, msrc, fs.SpecialFile, nil) -} - // mmapMinAddrData backs /proc/sys/vm/mmap_min_addr. // // +stateify savable @@ -101,36 +77,84 @@ func (*overcommitMemory) ReadSeqFileData(ctx context.Context, h seqfile.SeqHandl } func (p *proc) newKernelDir(ctx context.Context, msrc *fs.MountSource) *fs.Inode { - d := &ramfs.Dir{} - d.InitDir(ctx, nil, fs.RootOwner, fs.FilePermsFromMode(0555)) - d.AddChild(ctx, "hostname", p.newHostname(ctx, msrc)) - - d.AddChild(ctx, "shmmax", p.newStubProcFSFile(ctx, msrc, []byte(strconv.FormatUint(linux.SHMMAX, 10)))) - d.AddChild(ctx, "shmall", p.newStubProcFSFile(ctx, msrc, []byte(strconv.FormatUint(linux.SHMALL, 10)))) - d.AddChild(ctx, "shmmni", p.newStubProcFSFile(ctx, msrc, []byte(strconv.FormatUint(linux.SHMMNI, 10)))) - return newFile(d, msrc, fs.SpecialDirectory, nil) + h := hostname{ + SimpleFileInode: *fsutil.NewSimpleFileInode(ctx, fs.RootOwner, fs.FilePermsFromMode(0444), linux.PROC_SUPER_MAGIC), + } + + children := map[string]*fs.Inode{ + "hostname": newProcInode(&h, msrc, fs.SpecialFile, nil), + "shmall": newStaticProcInode(ctx, msrc, []byte(strconv.FormatUint(linux.SHMALL, 10))), + "shmmax": newStaticProcInode(ctx, msrc, []byte(strconv.FormatUint(linux.SHMMAX, 10))), + "shmmni": newStaticProcInode(ctx, msrc, []byte(strconv.FormatUint(linux.SHMMNI, 10))), + } + + d := ramfs.NewDir(ctx, children, fs.RootOwner, fs.FilePermsFromMode(0555)) + return newProcInode(d, msrc, fs.SpecialDirectory, nil) } func (p *proc) newVMDir(ctx context.Context, msrc *fs.MountSource) *fs.Inode { - d := &ramfs.Dir{} - d.InitDir(ctx, nil, fs.RootOwner, fs.FilePermsFromMode(0555)) - d.AddChild(ctx, "mmap_min_addr", seqfile.NewSeqFileInode(ctx, &mmapMinAddrData{p.k}, msrc)) - d.AddChild(ctx, "overcommit_memory", seqfile.NewSeqFileInode(ctx, &overcommitMemory{}, msrc)) - return newFile(d, msrc, fs.SpecialDirectory, nil) + children := map[string]*fs.Inode{ + "mmap_min_addr": seqfile.NewSeqFileInode(ctx, &mmapMinAddrData{p.k}, msrc), + "overcommit_memory": seqfile.NewSeqFileInode(ctx, &overcommitMemory{}, msrc), + } + d := ramfs.NewDir(ctx, children, fs.RootOwner, fs.FilePermsFromMode(0555)) + return newProcInode(d, msrc, fs.SpecialDirectory, nil) } func (p *proc) newSysDir(ctx context.Context, msrc *fs.MountSource) *fs.Inode { - d := &ramfs.Dir{} - d.InitDir(ctx, nil, fs.RootOwner, fs.FilePermsFromMode(0555)) - d.AddChild(ctx, "kernel", p.newKernelDir(ctx, msrc)) - d.AddChild(ctx, "vm", p.newVMDir(ctx, msrc)) + children := map[string]*fs.Inode{ + "kernel": p.newKernelDir(ctx, msrc), + "vm": p.newVMDir(ctx, msrc), + } // If we're using rpcinet we will let it manage /proc/sys/net. if _, ok := p.k.NetworkStack().(*rpcinet.Stack); ok { - d.AddChild(ctx, "net", newRPCInetProcSysNet(ctx, msrc)) + children["net"] = newRPCInetProcSysNet(ctx, msrc) } else { - d.AddChild(ctx, "net", p.newSysNetDir(ctx, msrc)) + children["net"] = p.newSysNetDir(ctx, msrc) } - return newFile(d, msrc, fs.SpecialDirectory, nil) + d := ramfs.NewDir(ctx, children, fs.RootOwner, fs.FilePermsFromMode(0555)) + return newProcInode(d, msrc, fs.SpecialDirectory, nil) +} + +// hostname is the inode for a file containing the system hostname. +// +// +stateify savable +type hostname struct { + fsutil.SimpleFileInode +} + +// GetFile implements fs.InodeOperations.GetFile. +func (h *hostname) GetFile(ctx context.Context, d *fs.Dirent, flags fs.FileFlags) (*fs.File, error) { + return fs.NewFile(ctx, d, flags, &hostnameFile{}), nil +} + +var _ fs.InodeOperations = (*hostname)(nil) + +// +stateify savable +type hostnameFile struct { + waiter.AlwaysReady `state:"nosave"` + fsutil.FileNoIoctl `state:"nosave"` + fsutil.FileNoMMap `state:"nosave"` + fsutil.FileNoSeek `state:"nosave"` + fsutil.FileNoopFlush `state:"nosave"` + fsutil.FileNoopFsync `state:"nosave"` + fsutil.FileNoopRelease `state:"nosave"` + fsutil.FileNotDirReaddir `state:"nosave"` + fsutil.FileNoWrite `state:"nosave"` } + +// Read implements fs.FileOperations.Read. +func (hf *hostnameFile) Read(ctx context.Context, _ *fs.File, dst usermem.IOSequence, offset int64) (int64, error) { + utsns := kernel.UTSNamespaceFromContext(ctx) + contents := []byte(utsns.HostName() + "\n") + if offset >= int64(len(contents)) { + return 0, io.EOF + } + n, err := dst.CopyOut(ctx, contents[offset:]) + return int64(n), err + +} + +var _ fs.FileOperations = (*hostnameFile)(nil) |