btrfs: handle chunk tree lookup error in btrfs_relocate_sys_chunks()

The unhandled case in btrfs_relocate_sys_chunks() loop is a corruption,
as it could be caused only by two impossible conditions:

- at first the search key is set up to look for a chunk tree item, with
  offset -1, this is an inexact search and the key->offset will contain
  the correct offset upon a successful search, a valid chunk tree item
  cannot have an offset -1

- after first successful search, the found_key corresponds to a chunk
  item, the offset is decremented by 1 before the next loop, it's
  impossible to find a chunk item there due to alignment and size
  constraints

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
David Sterba 2024-01-23 23:42:29 +01:00
parent a67242907b
commit 7411055db5
1 changed files with 11 additions and 1 deletions

View File

@ -3391,7 +3391,17 @@ again:
mutex_unlock(&fs_info->reclaim_bgs_lock);
goto error;
}
BUG_ON(ret == 0); /* Corruption */
if (ret == 0) {
/*
* On the first search we would find chunk tree with
* offset -1, which is not possible. On subsequent
* loops this would find an existing item on an invalid
* offset (one less than the previous one, wrong
* alignment and size).
*/
ret = -EUCLEAN;
goto error;
}
ret = btrfs_previous_item(chunk_root, path, key.objectid,
key.type);