diff options
| -rwxr-xr-x | pkg/sentry/fsimpl/kernfs/fd_impl_util.go | 30 |
1 files changed, 17 insertions, 13 deletions
diff --git a/pkg/sentry/fsimpl/kernfs/fd_impl_util.go b/pkg/sentry/fsimpl/kernfs/fd_impl_util.go index dd5806301..8284e76a7 100755 --- a/pkg/sentry/fsimpl/kernfs/fd_impl_util.go +++ b/pkg/sentry/fsimpl/kernfs/fd_impl_util.go @@ -22,6 +22,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/usermem" ) @@ -36,13 +37,20 @@ import ( // inode. // // Must be initialize with Init before first use. +// +// Lock ordering: mu => children.mu. type GenericDirectoryFD struct { vfs.FileDescriptionDefaultImpl vfs.DirectoryFileDescriptionDefaultImpl vfsfd vfs.FileDescription children *OrderedChildren - off int64 + + // mu protects the fields below. + mu sync.Mutex + + // off is the current directory offset. Protected by "mu". + off int64 } // NewGenericDirectoryFD creates a new GenericDirectoryFD and returns its @@ -115,17 +123,13 @@ func (fd *GenericDirectoryFD) inode() Inode { // IterDirents implements vfs.FileDecriptionImpl.IterDirents. IterDirents holds // o.mu when calling cb. func (fd *GenericDirectoryFD) IterDirents(ctx context.Context, cb vfs.IterDirentsCallback) error { - vfsFS := fd.filesystem() - fs := vfsFS.Impl().(*Filesystem) - vfsd := fd.vfsfd.VirtualDentry().Dentry() - - fs.mu.Lock() - defer fs.mu.Unlock() + fd.mu.Lock() + defer fd.mu.Unlock() opts := vfs.StatOptions{Mask: linux.STATX_INO} // Handle ".". if fd.off == 0 { - stat, err := fd.inode().Stat(vfsFS, opts) + stat, err := fd.inode().Stat(fd.filesystem(), opts) if err != nil { return err } @@ -143,8 +147,9 @@ func (fd *GenericDirectoryFD) IterDirents(ctx context.Context, cb vfs.IterDirent // Handle "..". if fd.off == 1 { + vfsd := fd.vfsfd.VirtualDentry().Dentry() parentInode := genericParentOrSelf(vfsd.Impl().(*Dentry)).inode - stat, err := parentInode.Stat(vfsFS, opts) + stat, err := parentInode.Stat(fd.filesystem(), opts) if err != nil { return err } @@ -168,7 +173,7 @@ func (fd *GenericDirectoryFD) IterDirents(ctx context.Context, cb vfs.IterDirent childIdx := fd.off - 2 for it := fd.children.nthLocked(childIdx); it != nil; it = it.Next() { inode := it.Dentry.Impl().(*Dentry).inode - stat, err := inode.Stat(vfsFS, opts) + stat, err := inode.Stat(fd.filesystem(), opts) if err != nil { return err } @@ -192,9 +197,8 @@ func (fd *GenericDirectoryFD) IterDirents(ctx context.Context, cb vfs.IterDirent // Seek implements vfs.FileDecriptionImpl.Seek. func (fd *GenericDirectoryFD) Seek(ctx context.Context, offset int64, whence int32) (int64, error) { - fs := fd.filesystem().Impl().(*Filesystem) - fs.mu.Lock() - defer fs.mu.Unlock() + fd.mu.Lock() + defer fd.mu.Unlock() switch whence { case linux.SEEK_SET: |