dm snapshot: free exception store on init failure

While initializing the snapshot module, if we fail to register
the snapshot target then we must back-out the exception store
module initialization.

Cc: stable@kernel.org
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Reviewed-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-snap.c b/drivers/md/dm-snap.c
index 3a53a5a9bec8..53f4063f7ea4 100644
--- a/drivers/md/dm-snap.c
+++ b/drivers/md/dm-snap.c
@@ -1470,7 +1470,7 @@ static int __init dm_snapshot_init(void)
         r = dm_register_target(&snapshot_target);
         if (r) {
                 DMERR("snapshot target register failed %d", r);
-                return r;
+                goto bad_register_snapshot_target;
         }
 
         r = dm_register_target(&origin_target);
@@ -1527,6 +1527,9 @@ bad2:
         dm_unregister_target(&origin_target);
 bad1:
         dm_unregister_target(&snapshot_target);
+
+bad_register_snapshot_target:
+        dm_exception_store_exit();
         return r;
 }