From 4bc7daf91a0d9102fa477b199964e7db45066da1 Mon Sep 17 00:00:00 2001 From: Jamie Liu Date: Wed, 17 Feb 2021 15:32:02 -0800 Subject: Check for directory emptiness in VFS1 overlay rmdir(). Note that this CL reorders overlayEntry.copyMu before overlayEntry.dirCacheMu in the overlayFileOperations.IterateDir() => readdirEntries() path - but this lock ordering is already required by overlayRemove/Bind() => overlayEntry.markDirectoryDirty(), so this actually just fixes an inconsistency. PiperOrigin-RevId: 358047121 --- pkg/sentry/fs/inode_overlay.go | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'pkg/sentry/fs/inode_overlay.go') diff --git a/pkg/sentry/fs/inode_overlay.go b/pkg/sentry/fs/inode_overlay.go index b16ab08ba..e97afc626 100644 --- a/pkg/sentry/fs/inode_overlay.go +++ b/pkg/sentry/fs/inode_overlay.go @@ -333,6 +333,19 @@ func overlayRemove(ctx context.Context, o *overlayEntry, parent *Dirent, child * } child.Inode.overlay.copyMu.RLock() defer child.Inode.overlay.copyMu.RUnlock() + if child.Inode.StableAttr.Type == Directory { + // RemoveDirectory requires that the directory is empty. + ser := &CollectEntriesSerializer{} + dirCtx := &DirCtx{ + Serializer: ser, + } + if _, err := overlayIterateDirLocked(ctx, child.Inode.overlay, child, dirCtx, 0); err != nil { + return err + } + if ser.Written() != 0 { + return syserror.ENOTEMPTY + } + } if child.Inode.overlay.upper != nil { if child.Inode.StableAttr.Type == Directory { if err := o.upper.InodeOperations.RemoveDirectory(ctx, o.upper, child.name); err != nil { -- cgit v1.2.3