The dereference should be moved below the NULL test.
spatch with a semantic match is used to found this.
(http://coccinelle.lip6.fr/)
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
                                        void (*put)(struct cflayer *lyr))
 {
        struct cfsrvl *service;
-       service = container_of(adapt_layer->dn, struct cfsrvl, layer);
 
-       WARN_ON(adapt_layer == NULL || adapt_layer->dn == NULL);
+       if (WARN_ON(adapt_layer == NULL || adapt_layer->dn == NULL))
+               return;
+       service = container_of(adapt_layer->dn, struct cfsrvl, layer);
        service->hold = hold;
        service->put = put;
 }