[ Upstream commit 53edb549565f55ccd0bdf43be3d66ce4c2d48b28 ]
As Al reported in link[1]:
f2fs_rename()
...
if (old_dir != new_dir && !whiteout)
f2fs_set_link(old_inode, old_dir_entry,
old_dir_page, new_dir);
else
f2fs_put_page(old_dir_page, 0);
You want correct inumber in the ".." link. And cross-directory
rename does move the source to new parent, even if you'd been asked
to leave a whiteout in the old place.
[1] https://lore.kernel.org/all/20231017055040.GN800259@ZenIV/
With below testcase, it may cause dirent corruption, due to it missed
to call f2fs_set_link() to update ".." link to new directory.
- mkdir -p dir/foo
- renameat2 -w dir/foo bar
[ASSERT] (__chk_dots_dentries:1421) --> Bad inode number[0x4] for '..', parent parent ino is [0x3]
[FSCK] other corrupted bugs [Fail]
Fixes: 7e01e7ad746b ("f2fs: support RENAME_WHITEOUT")
Cc: Jan Kara <jack@suse.cz>
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Chao Yu <chao@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>