net: udp: do not report ICMP redirects to user space

Redirect isn't an error condition, it should leave
the error handler without touching the socket.
Signed-off-by: NDuan Jiong <duanj.fnst@cn.fujitsu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv4/udp.c

@@ -658,7 +658,7 @@ void __udp4_lib_err(struct sk_buff *skb, u32 info, struct udp_table *udptable)
 		break;
 	case ICMP_REDIRECT:
 		ipv4_sk_redirect(skb, sk);
-		break;
+		goto out;
 	}
 
 	/*

net/ipv6/udp.c

@@ -525,8 +525,10 @@ void __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 
 	if (type == ICMPV6_PKT_TOOBIG)
 		ip6_sk_update_pmtu(skb, sk, info);
-	if (type == NDISC_REDIRECT)
+	if (type == NDISC_REDIRECT) {
 		ip6_sk_redirect(skb, sk);
+		goto out;
+	}
 
 	np = inet6_sk(sk);