netfilter: rt: account for tcp header size too

This needs to accout for the ipv4/ipv6 header size and the tcp
header without options.

Fixes: 6b5dc98e8f ("netfilter: rt: add support to fetch path mss")
Reported-by: Matteo Croce <technoboy85@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Florian Westphal 2017-08-28 17:00:12 +02:00 committed by Pablo Neira Ayuso
parent d11dd6cdc3
commit 1aff64715e

View File

@ -35,10 +35,11 @@ static u16 get_tcpmss(const struct nft_pktinfo *pkt, const struct dst_entry *skb
switch (nft_pf(pkt)) {
case NFPROTO_IPV4:
fl.u.ip4.daddr = ip_hdr(skb)->saddr;
minlen = sizeof(struct iphdr);
minlen = sizeof(struct iphdr) + sizeof(struct tcphdr);
break;
case NFPROTO_IPV6:
fl.u.ip6.daddr = ipv6_hdr(skb)->saddr;
minlen = sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
break;
}