The patch below does not apply to the 5.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y git checkout FETCH_HEAD git cherry-pick -x 31723c9542dba1681cc3720571fdf12ffe0eddd9 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2024081954-purplish-scarecrow-7568@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..

Possible dependencies:

31723c9542db ("btrfs: tree-checker: reject BTRFS_FT_UNKNOWN dir type") 94a48aef49f2 ("btrfs: extend btrfs_dir_item type to store encryption status") e43eec81c516 ("btrfs: use struct qstr instead of name and namelen pairs") 07e81dc94474 ("btrfs: move accessor helpers into accessors.h") ad1ac5012c2b ("btrfs: move btrfs_map_token to accessors") 55e5cfd36da5 ("btrfs: remove fs_info::pending_changes and related code") 7966a6b5959b ("btrfs: move fs_info::flags enum to fs.h") fc97a410bd78 ("btrfs: move mount option definitions to fs.h") 0d3a9cf8c306 ("btrfs: convert incompat and compat flag test helpers to macros") ec8eb376e271 ("btrfs: move BTRFS_FS_STATE* definitions and helpers to fs.h") 9b569ea0be6f ("btrfs: move the printk helpers out of ctree.h") e118578a8df7 ("btrfs: move assert helpers out of ctree.h") c7f13d428ea1 ("btrfs: move fs wide helpers out of ctree.h") 63a7cb130718 ("btrfs: auto enable discard=async when possible") 7a66eda351ba ("btrfs: move the btrfs_verity_descriptor_item defs up in ctree.h") 956504a331a6 ("btrfs: move trans_handle_cachep out of ctree.h") f1e5c6185ca1 ("btrfs: move flush related definitions to space-info.h") ed4c491a3db2 ("btrfs: move BTRFS_MAX_MIRRORS into scrub.c") 4300c58f8090 ("btrfs: move btrfs on-disk definitions out of ctree.h") d60d956eb41f ("btrfs: remove unused set/clear_pending_info helpers")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 31723c9542dba1681cc3720571fdf12ffe0eddd9 Mon Sep 17 00:00:00 2001 From: Qu Wenruo wqu@suse.com Date: Mon, 12 Aug 2024 08:52:44 +0930 Subject: [PATCH] btrfs: tree-checker: reject BTRFS_FT_UNKNOWN dir type

[REPORT] There is a bug report that kernel is rejecting a mismatching inode mode and its dir item:

[ 1881.553937] BTRFS critical (device dm-0): inode mode mismatch with dir: inode mode=040700 btrfs type=2 dir type=0

[CAUSE] It looks like the inode mode is correct, while the dir item type 0 is BTRFS_FT_UNKNOWN, which should not be generated by btrfs at all.

This may be caused by a memory bit flip.

[ENHANCEMENT] Although tree-checker is not able to do any cross-leaf verification, for this particular case we can at least reject any dir type with BTRFS_FT_UNKNOWN.

So here we enhance the dir type check from [0, BTRFS_FT_MAX), to (0, BTRFS_FT_MAX). Although the existing corruption can not be fixed just by such enhanced checking, it should prevent the same 0x2->0x0 bitflip for dir type to reach disk in the future.

Reported-by: Kota nospam@kota.moe Link: https://lore.kernel.org/linux-btrfs/CACsxjPYnQF9ZF-0OhH16dAx50=BXXOcP74MxBc3... CC: stable@vger.kernel.org # 5.4+ Signed-off-by: Qu Wenruo wqu@suse.com Signed-off-by: David Sterba dsterba@suse.com

diff --git a/fs/btrfs/tree-checker.c b/fs/btrfs/tree-checker.c index a825fa598e3c..6f1e2f2215d9 100644 --- a/fs/btrfs/tree-checker.c +++ b/fs/btrfs/tree-checker.c @@ -569,9 +569,10 @@ static int check_dir_item(struct extent_buffer *leaf,

/* dir type check */ dir_type = btrfs_dir_ftype(leaf, di); - if (unlikely(dir_type >= BTRFS_FT_MAX)) { + if (unlikely(dir_type <= BTRFS_FT_UNKNOWN || + dir_type >= BTRFS_FT_MAX)) { dir_item_err(leaf, slot, - "invalid dir item type, have %u expect [0, %u)", + "invalid dir item type, have %u expect (0, %u)", dir_type, BTRFS_FT_MAX); return -EUCLEAN; }