Re: [PATCH 2/2] ipvs: Extend MTU check to account for IPv6 NAT defrag changes

Patrick McHardy
2012-08-28T08:22:05Z

On Mon, 27 Aug 2012, Julian Anastasov wrote:

>
> Hello,
>
> On Mon, 27 Aug 2012, Jesper Dangaard Brouer wrote:
>
>> This patch is necessary, to make IPVS work, after Patrick McHardys
>> IPv6 NAT defragmentation changes.
>>
>> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
>> ---
>>
>> I would appriciate, if someone (e.g. Julian) double check the tunnel mode code.
>
> Sure
>
>> --Jesper
>>
>> net/netfilter/ipvs/ip_vs_xmit.c | 16 +++++++++++++---
>> 1 files changed, 13 insertions(+), 3 deletions(-)
>>
>> @@ -956,8 +963,11 @@ ip_vs_tunnel_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
>> skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu);
>>
>> /* MTU checking: Special for tunnel mode */
>> - if (mtu < ntohs(old_iph->payload_len) + sizeof(struct ipv6hdr) &&
>> - !skb_is_gso(skb)) {
>> + if ((!IP6CB(skb)->frag_max_size &&
>> + (mtu < ntohs(old_iph->payload_len) + sizeof(struct ipv6hdr) &&
>> + !skb_is_gso(skb)))
>> + || IP6CB(skb)->frag_max_size + sizeof(struct ipv6hdr) > mtu) {
>> +
>
> mtu is already reduced with the new outer header size,
> may be we can just call __mtu_check_toobig_v6 with mtu?
>
>> if (!skb->dev) {
>> struct net *net = dev_net(skb_dst(skb)->dev);
>
> All other changes in patch 1 and 2 look ok and
> I'll ack them next time.

I'd like to take the final patches through my nat-ipv6 tree in order
to avoid temporary regressions. Please let me know when they're ready
for applying.