dm cache: avoid calling policy destructor twice on error

If the cache policy's config values are not able to be set we must
set the policy to NULL after destroying it in create_cache_policy()
so we don't attempt to destroy it a second time later.

Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c
index 76cc910557f0..79ac8603644d 100644
--- a/drivers/md/dm-cache-target.c
+++ b/drivers/md/dm-cache-target.c
@@ -1763,8 +1763,11 @@ static int create_cache_policy(struct cache *cache, struct cache_args *ca,
         }
 
         r = set_config_values(cache->policy, ca->policy_argc, ca->policy_argv);
-        if (r)
+        if (r) {
+                *error = "Error setting cache policy's config values";
                 dm_cache_policy_destroy(cache->policy);
+                cache->policy = NULL;
+        }
 
         return r;
 }