diff options
| author | Zhiyu Zhang <zhiyuzhang999@gmail.com> | 2026-01-01 19:11:48 +0800 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2026-01-26 19:07:13 -0800 |
| commit | 8cafcb881364af5ef3a8b9fed4db254054033d8a (patch) | |
| tree | 6daf31d36592bbcad7a949023909c86418b14d67 /include | |
| parent | 25929dae28f528d7d74992edabd38bf3c374e485 (diff) | |
fat: avoid parent link count underflow in rmdir
Corrupted FAT images can leave a directory inode with an incorrect
i_nlink (e.g. 2 even though subdirectories exist). rmdir then
unconditionally calls drop_nlink(dir) and can drive i_nlink to 0,
triggering the WARN_ON in drop_nlink().
Add a sanity check in vfat_rmdir() and msdos_rmdir(): only drop the
parent link count when it is at least 3, otherwise report a filesystem
error.
Link: https://lkml.kernel.org/r/20260101111148.1437-1-zhiyuzhang999@gmail.com
Fixes: 9a53c3a783c2 ("[PATCH] r/o bind mounts: unlink: monitor i_nlink")
Signed-off-by: Zhiyu Zhang <zhiyuzhang999@gmail.com>
Reported-by: Zhiyu Zhang <zhiyuzhang999@gmail.com>
Closes: https://lore.kernel.org/linux-fsdevel/aVN06OKsKxZe6-Kv@casper.infradead.org/T/#t
Tested-by: Zhiyu Zhang <zhiyuzhang999@gmail.com>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'include')
0 files changed, 0 insertions, 0 deletions