Btrfs: fix panic in balance due to EIO
During build_backref_tree(), if we fail to read a btree node,
we can eventually run into BUG_ON(cache->nr_nodes) that we put
in backref_cache_cleanup(), meaning we have at least one
memory leak.
This frees the backref_node that we's allocated at the very
beginning of build_backref_tree().
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index 13c9a48..97cafe7 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -1171,8 +1171,12 @@
lower = list_entry(useless.next,
struct backref_node, list);
list_del_init(&lower->list);
+ if (lower == node)
+ node = NULL;
free_backref_node(cache, lower);
}
+
+ free_backref_node(cache, node);
return ERR_PTR(err);
}
ASSERT(!node || !node->detached);