Phonet: missing rcu_dereference()

Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Rémi Denis-Courmont <remi.denis-courmont@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/phonet/af_phonet.c

@@ -44,7 +44,7 @@ static struct phonet_protocol *phonet_proto_get(int protocol)
 		return NULL;
 
 	rcu_read_lock();
-	pp = proto_tab[protocol];
+	pp = rcu_dereference(proto_tab[protocol]);
 	if (pp && !try_module_get(pp->prot->owner))
 		pp = NULL;
 	rcu_read_unlock();