Merge tag 'pull-rename' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull rename updates from Al Viro:
 "Fix directory locking scheme on rename

  This was broken in 6.5; we really can't lock two unrelated directories
  without holding ->s_vfs_rename_mutex first and in case of same-parent
  rename of a subdirectory 6.5 ends up doing just that"

* tag 'pull-rename' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  rename(): avoid a deadlock in the case of parents having no common ancestor
  kill lock_two_inodes()
  rename(): fix the locking of subdirectories
  f2fs: Avoid reading renamed directory if parent does not change
  ext4: don't access the source subdirectory content on same-directory rename
  ext2: Avoid reading renamed directory if parent does not change
  udf_rename(): only access the child content on cross-directory rename
  ocfs2: Avoid touching renamed directory if parent does not change
  reiserfs: Avoid touching renamed directory if parent does not change

1 files changed, 6 insertions, 1 deletions

diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c
index 22b519763267..0217094c23ea 100644
--- a/fs/overlayfs/util.c
+++ b/fs/overlayfs/util.c
@@ -1198,12 +1198,17 @@ void ovl_nlink_end(struct dentry *dentry)
 
 int ovl_lock_rename_workdir(struct dentry *workdir, struct dentry *upperdir)
 {
+	struct dentry *trap;
+
 	/* Workdir should not be the same as upperdir */
 	if (workdir == upperdir)
 		goto err;
 
 	/* Workdir should not be subdir of upperdir and vice versa */
-	if (lock_rename(workdir, upperdir) != NULL)
+	trap = lock_rename(workdir, upperdir);
+	if (IS_ERR(trap))
+		goto err;
+	if (trap)
 		goto err_unlock;
 
 	return 0;