From 72d4d3e3980702809509586d36015b7c3c51fad4 Mon Sep 17 00:00:00 2001 From: Jozsef Kadlecsik Date: Sat, 21 Apr 2018 13:43:48 +0200 Subject: netfilter: Fix handling simultaneous open in TCP conntrack Dominique Martinet reported a TCP hang problem when simultaneous open was used. The problem is that the tcp_conntracks state table is not smart enough to handle the case. The state table could be fixed by introducing a new state, but that would require more lines of code compared to this patch, due to the required backward compatibility with ctnetlink. Signed-off-by: Jozsef Kadlecsik Reported-by: Dominique Martinet Tested-by: Dominique Martinet Signed-off-by: Pablo Neira Ayuso --- include/uapi/linux/netfilter/nf_conntrack_tcp.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/netfilter/nf_conntrack_tcp.h b/include/uapi/linux/netfilter/nf_conntrack_tcp.h index 74b91151d494..bcba72def817 100644 --- a/include/uapi/linux/netfilter/nf_conntrack_tcp.h +++ b/include/uapi/linux/netfilter/nf_conntrack_tcp.h @@ -46,6 +46,9 @@ enum tcp_conntrack { /* Marks possibility for expected RFC5961 challenge ACK */ #define IP_CT_EXP_CHALLENGE_ACK 0x40 +/* Simultaneous open initialized */ +#define IP_CT_TCP_SIMULTANEOUS_OPEN 0x80 + struct nf_ct_tcp_flags { __u8 flags; __u8 mask; -- cgit v1.2.3-71-gd317