diff options
| -rw-r--r-- | pkg/sentry/fs/inode_overlay.go | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/pkg/sentry/fs/inode_overlay.go b/pkg/sentry/fs/inode_overlay.go index 77a2623ef..b11e2bd13 100644 --- a/pkg/sentry/fs/inode_overlay.go +++ b/pkg/sentry/fs/inode_overlay.go @@ -131,11 +131,20 @@ func overlayLookup(ctx context.Context, parent *overlayEntry, inode *Inode, name } if child != nil { if !child.IsNegative() { - // Did we find something in the upper filesystem? We can - // only use it if the types match. - if upperInode == nil || upperInode.StableAttr.Type == child.Inode.StableAttr.Type { + if upperInode == nil { + // If nothing was in the upper, use what we found in the lower. lowerInode = child.Inode lowerInode.IncRef() + } else { + // If we have something from the upper, we can only use it if the types + // match. + // NOTE: Allow SpecialDirectories and Directories to merge. + // This is needed to allow submounts in /proc and /sys. + if upperInode.StableAttr.Type == child.Inode.StableAttr.Type || + (IsDir(upperInode.StableAttr) && IsDir(child.Inode.StableAttr)) { + lowerInode = child.Inode + lowerInode.IncRef() + } } } child.DecRef() |