ipv6: pass up EMSGSIZE msg for UDP socket in Ipv6 (e0d8c1b7) · Commits · 戴 / test

In ipv4, when the machine receives a ICMP_FRAG_NEEDED message, the connected UDP socket will get EMSGSIZE message on its next read from the socket. However, this is not the case for ipv6. This fix modifies the udp err handler in Ipv6 for ICMP6_PKT_TOOBIG to make it similar to ipv4 behavior. That is when the machine gets an ICMP6_PKT_TOOBIG message, the connected UDP socket will get EMSGSIZE message on its next read from the socket. Signed-off-by:

Wei Wang <weiwan@google.com> Acked-by:

Eric Dumazet <edumazet@google.com> Signed-off-by:

David S. Miller <davem@davemloft.net>

net/ipv6/udp.c

+11 −9

Original line number	Diff line number	Diff line
		@@ -548,6 +548,7 @@ void __udp6_lib_err(struct sk_buff skb, struct inet6_skb_parm opt,
		const struct in6_addr *daddr = &hdr->daddr;
		struct udphdr uh = (struct udphdr )(skb->data+offset);
		struct sock *sk;
		int harderr;
		int err;
		struct net *net = dev_net(skb->dev);

		@@ -559,26 +560,27 @@ void __udp6_lib_err(struct sk_buff skb, struct inet6_skb_parm opt,
		return;
		}

		harderr = icmpv6_err_convert(type, code, &err);
		np = inet6_sk(sk);

		if (type == ICMPV6_PKT_TOOBIG) {
		if (!ip6_sk_accept_pmtu(sk))
		goto out;
		ip6_sk_update_pmtu(skb, sk, info);
		if (np->pmtudisc != IPV6_PMTUDISC_DONT)
		harderr = 1;
		}
		if (type == NDISC_REDIRECT) {
		ip6_sk_redirect(skb, sk);
		goto out;
		}

		np = inet6_sk(sk);

		if (!icmpv6_err_convert(type, code, &err) && !np->recverr)
		if (!np->recverr) {
		if (!harderr \|\| sk->sk_state != TCP_ESTABLISHED)
		goto out;

		if (sk->sk_state != TCP_ESTABLISHED && !np->recverr)
		goto out;

		if (np->recverr)
		} else {
		ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
		}

		sk->sk_err = err;
		sk->sk_error_report(sk);

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