tunnel: do not confirm neighbor when do pmtu update (7a1592bc) · Commits · 戴 / test

When do tunnel PMTU update and calls __ip6_rt_update_pmtu() in the end, we should not call dst_confirm_neigh() as there is no two-way communication. v5: No Change. v4: Update commit description v3: Do not remove dst_confirm_neigh, but add a new bool parameter in dst_ops.update_pmtu to control whether we should do neighbor confirm. Also split the big patch to small ones for each area. v2: Remove dst_confirm_neigh in __ip6_rt_update_pmtu. Fixes: ("net: use dst_confirm_neigh for UDP, RAW, ICMP, L2TP") Reviewed-by:

Guillaume Nault <gnault@redhat.com> Tested-by:

Guillaume Nault <gnault@redhat.com> Acked-by:

David Ahern <dsahern@gmail.com> Signed-off-by:

Hangbin Liu <liuhangbin@gmail.com> Signed-off-by:

David S. Miller <davem@davemloft.net>

net/ipv4/ip_tunnel.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -505,7 +505,7 @@ static int tnl_update_pmtu(struct net_device dev, struct sk_buff skb,
		mtu = skb_valid_dst(skb) ? dst_mtu(skb_dst(skb)) : dev->mtu;

		if (skb_valid_dst(skb))
		skb_dst_update_pmtu(skb, mtu);
		skb_dst_update_pmtu_no_confirm(skb, mtu);

		if (skb->protocol == htons(ETH_P_IP)) {
		if (!skb_is_gso(skb) &&

net/ipv6/ip6_tunnel.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -640,7 +640,7 @@ ip4ip6_err(struct sk_buff skb, struct inet6_skb_parm opt,
		if (rel_info > dst_mtu(skb_dst(skb2)))
		goto out;

		skb_dst_update_pmtu(skb2, rel_info);
		skb_dst_update_pmtu_no_confirm(skb2, rel_info);
		}

		icmp_send(skb2, rel_type, rel_code, htonl(rel_info));
		@@ -1132,7 +1132,7 @@ route_lookup:
		mtu = max(mtu, skb->protocol == htons(ETH_P_IPV6) ?
		IPV6_MIN_MTU : IPV4_MIN_MTU);

		skb_dst_update_pmtu(skb, mtu);
		skb_dst_update_pmtu_no_confirm(skb, mtu);
		if (skb->len - t->tun_hlen - eth_hlen > mtu && !skb_is_gso(skb)) {
		*pmtu = mtu;
		err = -EMSGSIZE;

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