diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 1b7bb9d..da215e5 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -3091,6 +3091,10 @@ static int packet_do_bind(struct sock *sk, const char *name, int ifindex,
 	if (need_rehook) {
 		if (po->running) {
 			rcu_read_unlock();
+			/* prevents packet_notifier() from calling
+			 * register_prot_hook()
+			 */
+			po->num = 0;
 			__unregister_prot_hook(sk, true);
 			rcu_read_lock();
 			dev_curr = po->prot_hook.dev;
@@ -3099,6 +3103,7 @@ static int packet_do_bind(struct sock *sk, const char *name, int ifindex,
 								 dev->ifindex);
 		}
 
+		BUG_ON(po->running);
 		po->num = proto;
 		po->prot_hook.type = proto;