ipv6: ip6_route_output() never returns NULL.

ip6_route_output() never returns NULL, so it is wrong to
check if the return value is NULL.

Signed-off-by: RongQing.Li <roy.qing.li@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv6/ip6mr.c

@@ -1926,8 +1926,10 @@ static int ip6mr_forward2(struct net *net, struct mr6_table *mrt,
 	};
 
 	dst = ip6_route_output(net, NULL, &fl6);
-	if (!dst)
+	if (dst->error) {
+		dst_release(dst);
 		goto out_free;
+	}
 
 	skb_dst_drop(skb);
 	skb_dst_set(skb, dst);

net/ipv6/ndisc.c

@@ -1545,9 +1545,10 @@ void ndisc_send_redirect(struct sk_buff *skb, struct neighbour *neigh,
 			 &saddr_buf, &ipv6_hdr(skb)->saddr, dev->ifindex);
 
 	dst = ip6_route_output(net, NULL, &fl6);
-	if (dst == NULL)
+	if (dst->error) {
+		dst_release(dst);
 		return;
-
+	}
 	dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), NULL, 0);
 	if (IS_ERR(dst))
 		return;