dm cache: fix error return code in cache_create

Return -ENOMEM if memory allocation fails in cache_create
instead of 0 (to avoid NULL pointer dereference).

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Cc: stable@vger.kernel.org
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c
index 10744091e6ca..6feaba24fcac 100644
--- a/drivers/md/dm-cache-target.c
+++ b/drivers/md/dm-cache-target.c
@@ -1971,6 +1971,7 @@ static int cache_create(struct cache_args *ca, struct cache **result)
         atomic_set(&cache->nr_migrations, 0);
         init_waitqueue_head(&cache->migration_wait);
 
+        r = -ENOMEM;
         cache->nr_dirty = 0;
         cache->dirty_bitset = alloc_bitset(from_cblock(cache->cache_size));
         if (!cache->dirty_bitset) {