When zero window is announced we can get into a situation where connection stays around forever: 1. One side announces zero window. 2. Other side closes. In this case, no FIN is sent (stuck in send queue). Unless other side opens the window up again conntrack stays in ESTABLISHED state for a very long time. Lets alleviate this by lowering the timeout to RETRANS (5 minutes), the other end should be sending zero window probes to keep the connection established as long as a socket still exists. Cc: Jozsef Kadlecsik <kadlec@xxxxxxxxxxxxxxxxx> Signed-off-by: Florian Westphal <fw@xxxxxxxxx> --- net/netfilter/nf_conntrack_proto_tcp.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/netfilter/nf_conntrack_proto_tcp.c b/net/netfilter/nf_conntrack_proto_tcp.c index c11b04d269ea..684cc29010a0 100644 --- a/net/netfilter/nf_conntrack_proto_tcp.c +++ b/net/netfilter/nf_conntrack_proto_tcp.c @@ -1039,6 +1039,9 @@ static int tcp_packet(struct nf_conn *ct, IP_CT_TCP_FLAG_DATA_UNACKNOWLEDGED && timeouts[new_state] > timeouts[TCP_CONNTRACK_UNACK]) timeout = timeouts[TCP_CONNTRACK_UNACK]; + else if (ct->proto.tcp.last_win == 0 && + timeouts[new_state] > timeouts[TCP_CONNTRACK_RETRANS]) + timeout = timeouts[TCP_CONNTRACK_RETRANS]; else timeout = timeouts[new_state]; spin_unlock_bh(&ct->lock); -- 2.13.6 -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
