[PATCH 5.12 153/296] afs: Fix the nlink handling of dir-over-dir rename

From: Greg Kroah-Hartman
Date: Mon May 31 2021 - 12:28:45 EST


From: David Howells <dhowells@xxxxxxxxxx>

commit f610a5a29c3cfb7d37bdfa4ef52f72ea51f24a76 upstream.

Fix rename of one directory over another such that the nlink on the deleted
directory is cleared to 0 rather than being decremented to 1.

This was causing the generic/035 xfstest to fail.

Fixes: e49c7b2f6de7 ("afs: Build an abstraction around an "operation" concept")
Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
Reviewed-by: Marc Dionne <marc.dionne@xxxxxxxxxxxx>
cc: linux-afs@xxxxxxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/162194384460.3999479.7605572278074191079.stgit@xxxxxxxxxxxxxxxxxxxxxx/ # v1
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/afs/dir.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

--- a/fs/afs/dir.c
+++ b/fs/afs/dir.c
@@ -1842,7 +1842,9 @@ static void afs_rename_edit_dir(struct a
new_inode = d_inode(new_dentry);
if (new_inode) {
spin_lock(&new_inode->i_lock);
- if (new_inode->i_nlink > 0)
+ if (S_ISDIR(new_inode->i_mode))
+ clear_nlink(new_inode);
+ else if (new_inode->i_nlink > 0)
drop_nlink(new_inode);
spin_unlock(&new_inode->i_lock);
}