6.10-stable review patch. If anyone has any objections, please let me know.
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From: Qu Wenruo wqu@suse.com
commit 31723c9542dba1681cc3720571fdf12ffe0eddd9 upstream.
[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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/btrfs/tree-checker.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
--- a/fs/btrfs/tree-checker.c +++ b/fs/btrfs/tree-checker.c @@ -551,9 +551,10 @@ static int check_dir_item(struct extent_
/* 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; }