Amir Goldstein f47c834a91 fs: relax assertions on failure to encode file handles ... commit 974e3fe0ac upstream. Encoding file handles is usually performed by a filesystem >encode_fh() method that may fail for various reasons. The legacy users of exportfs_encode_fh(), namely, nfsd and name_to_handle_at(2) syscall are ready to cope with the possibility of failure to encode a file handle. There are a few other users of exportfs_encode_{fh,fid}() that currently have a WARN_ON() assertion when ->encode_fh() fails. Relax those assertions because they are wrong. The second linked bug report states commit 16aac5ad1f ("ovl: support encoding non-decodable file handles") in v6.6 as the regressing commit, but this is not accurate. The aforementioned commit only increases the chances of the assertion and allows triggering the assertion with the reproducer using overlayfs, inotify and drop_caches. Triggering this assertion was always possible with other filesystems and other reasons of ->encode_fh() failures and more particularly, it was also possible with the exact same reproducer using overlayfs that is mounted with options index=on,nfs_export=on also on kernels < v6.6. Therefore, I am not listing the aforementioned commit as a Fixes commit. Backport hint: this patch will have a trivial conflict applying to v6.6.y, and other trivial conflicts applying to stable kernels < v6.6. Reported-by: syzbot+ec07f6f5ce62b858579f@syzkaller.appspotmail.com Tested-by: syzbot+ec07f6f5ce62b858579f@syzkaller.appspotmail.com Closes: https://lore.kernel.org/linux-unionfs/671fd40c.050a0220.4735a.024f.GAE@google.com/ Reported-by: Dmitry Safonov <dima@arista.com> Closes: https://lore.kernel.org/linux-fsdevel/CAGrbwDTLt6drB9eaUagnQVgdPBmhLfqqxAf3F+Juqy_o6oP8uw@mail.gmail.com/ Cc: stable@vger.kernel.org Signed-off-by: Amir Goldstein <amir73il@gmail.com> Link: https://lore.kernel.org/r/20241219115301.465396-1-amir73il@gmail.com Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2025-01-23 17:21:19 +01:00
..
dnotify	dnotify: Pass argument of fcntl_dirnotify as int	2023-07-10 14:36:12 +02:00
fanotify	fanotify: allow reporting errors on failure to open fd	2024-12-14 20:00:05 +01:00
inotify	inotify: Avoid reporting event with invalid wd	2023-04-25 12:36:55 +02:00
fdinfo.c	fs: relax assertions on failure to encode file handles	2025-01-23 17:21:19 +01:00
fdinfo.h
fsnotify.c	fsnotify: fix sending inotify event with unexpected filename	2024-12-09 10:32:44 +01:00
fsnotify.h	fsnotify: clear PARENT_WATCHED flags lazily	2024-09-08 07:54:44 +02:00
group.c	fsnotify: create helpers for group mark_mutex lock	2022-04-25 14:37:22 +02:00
Kconfig	fs/notify: Remove "select SRCU"	2023-02-02 16:26:06 -08:00
Makefile
mark.c	fsnotify: clear PARENT_WATCHED flags lazily	2024-09-08 07:54:44 +02:00
notification.c