This is a note to let you know that I've just added the patch titled btrfs: convert BUG_ON in btrfs_reloc_cow_block() to proper error handling to the 6.13-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: btrfs-convert-bug_on-in-btrfs_reloc_cow_block-to-pro.patch and it can be found in the queue-6.13 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 190c9a146bb19fda0f5de66c2c4a0f9f776307d0 Author: Josef Bacik <josef@xxxxxxxxxxxxxx> Date: Thu Oct 3 11:43:03 2024 -0400 btrfs: convert BUG_ON in btrfs_reloc_cow_block() to proper error handling [ Upstream commit 6a4730b325aaa48f7a5d5ba97aff0a955e2d9cec ] This BUG_ON is meant to catch backref cache problems, but these can arise from either bugs in the backref cache or corruption in the extent tree. Fix it to be a proper error. Reviewed-by: Boris Burkov <boris@xxxxxx> Signed-off-by: Josef Bacik <josef@xxxxxxxxxxxxxx> Reviewed-by: David Sterba <dsterba@xxxxxxxx> Signed-off-by: David Sterba <dsterba@xxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c index db8b42f674b7c..ab2de2d1b2bee 100644 --- a/fs/btrfs/relocation.c +++ b/fs/btrfs/relocation.c @@ -4405,8 +4405,18 @@ int btrfs_reloc_cow_block(struct btrfs_trans_handle *trans, WARN_ON(!first_cow && level == 0); node = rc->backref_cache.path[level]; - BUG_ON(node->bytenr != buf->start && - node->new_bytenr != buf->start); + + /* + * If node->bytenr != buf->start and node->new_bytenr != + * buf->start then we've got the wrong backref node for what we + * expected to see here and the cache is incorrect. + */ + if (unlikely(node->bytenr != buf->start && node->new_bytenr != buf->start)) { + btrfs_err(fs_info, +"bytenr %llu was found but our backref cache was expecting %llu or %llu", + buf->start, node->bytenr, node->new_bytenr); + return -EUCLEAN; + } btrfs_backref_drop_node_buffer(node); atomic_inc(&cow->refs);