s390/zcrypt: Fixed possible race condition in zcrypt module handling

Signed-off-by: Ingo Tuchscherer <ingo.tuchscherer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 3 insertions, 4 deletions

diff --git a/drivers/s390/crypto/zcrypt_api.c b/drivers/s390/crypto/zcrypt_api.c
index 0e18c5dcd91f..08f1830cbfc4 100644
--- a/drivers/s390/crypto/zcrypt_api.c
+++ b/drivers/s390/crypto/zcrypt_api.c
@@ -343,10 +343,11 @@ struct zcrypt_ops *__ops_lookup(unsigned char *name, int variant)
                         break;
                 }
         }
+        if (!found || !try_module_get(zops->owner))
+                zops = NULL;
+
         spin_unlock_bh(&zcrypt_ops_list_lock);
 
-        if (!found)
-                return NULL;
         return zops;
 }
 
@@ -359,8 +360,6 @@ struct zcrypt_ops *zcrypt_msgtype_request(unsigned char *name, int variant)
                 request_module("%s", name);
                 zops = __ops_lookup(name, variant);
         }
-        if ((!zops) || (!try_module_get(zops->owner)))
-                return NULL;
         return zops;
 }
 EXPORT_SYMBOL(zcrypt_msgtype_request);