[PATCH AUTOSEL 6.3 02/18] btrfs: abort transaction when sibling keys check fails for leaves

From: Sasha Levin
Date: Sat May 20 2023 - 14:18:04 EST


From: Filipe Manana <fdmanana@xxxxxxxx>

[ Upstream commit 9ae5afd02a03d4e22a17a9609b19400b77c36273 ]

If the sibling keys check fails before we move keys from one sibling
leaf to another, we are not aborting the transaction - we leave that to
some higher level caller of btrfs_search_slot() (or anything else that
uses it to insert items into a b+tree).

This means that the transaction abort will provide a stack trace that
omits the b+tree modification call chain. So change this to immediately
abort the transaction and therefore get a more useful stack trace that
shows us the call chain in the bt+tree modification code.

It's also important to immediately abort the transaction just in case
some higher level caller is not doing it, as this indicates a very
serious corruption and we should stop the possibility of doing further
damage.

Reviewed-by: Qu Wenruo <wqu@xxxxxxxx>
Signed-off-by: Filipe Manana <fdmanana@xxxxxxxx>
Reviewed-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/btrfs/ctree.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 26bb10b6ca85d..986827370d8e1 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -3222,6 +3222,7 @@ static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root

if (check_sibling_keys(left, right)) {
ret = -EUCLEAN;
+ btrfs_abort_transaction(trans, ret);
btrfs_tree_unlock(right);
free_extent_buffer(right);
return ret;
@@ -3444,6 +3445,7 @@ static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root

if (check_sibling_keys(left, right)) {
ret = -EUCLEAN;
+ btrfs_abort_transaction(trans, ret);
goto out;
}
return __push_leaf_left(trans, path, min_data_size, empty, left,
--
2.39.2