From 7569141e8fa855b509e674456132b83bca5f087c Mon Sep 17 00:00:00 2001 From: Filipe Manana Date: Fri, 9 Jun 2023 11:49:07 +0100 Subject: btrfs: replace BUG_ON() at split_item() with proper error handling There's no need to BUG_ON() at split_item() if the leaf does not have enough free space for the new item, we can just return -ENOSPC since the caller can deal with errors from split_item(). Also, as this is a very unlikely condition to happen, because the caller has invoked setup_leaf_for_split() before calling split_item(), surround the condition with a WARN_ON() which makes it easier to notice this unexpected condition and tags the if branch with 'unlikely' as well. I've actually once hit this BUG_ON() with some incorrect code changes I had, which was very inconvenient as it required rebooting the VM. Reviewed-by: Qu Wenruo Signed-off-by: Filipe Manana Signed-off-by: David Sterba --- fs/btrfs/ctree.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'fs/btrfs') diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index 190dd90a88eb..a4cb4b642987 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -4000,7 +4000,12 @@ static noinline int split_item(struct btrfs_path *path, struct btrfs_disk_key disk_key; leaf = path->nodes[0]; - BUG_ON(btrfs_leaf_free_space(leaf) < sizeof(struct btrfs_item)); + /* + * Shouldn't happen because the caller must have previously called + * setup_leaf_for_split() to make room for the new item in the leaf. + */ + if (WARN_ON(btrfs_leaf_free_space(leaf) < sizeof(struct btrfs_item))) + return -ENOSPC; orig_slot = path->slots[0]; orig_offset = btrfs_item_offset(leaf, path->slots[0]); -- cgit v1.2.3