When the synproxy_parse_options is called on the client ack the mss option will not be present. Consequently mss wont be included in the backend syn packet, which falls back to 536 bytes mss. Therefore XT_SYNPROXY_OPT_MSS is explicitly flagged when recovering mss value from cookie. Signed-off-by: Martin Topholm <mph@xxxxxxx> Reviewed-by: Jesper Dangaard Brouer <brouer@xxxxxxxxxx> --- net/ipv4/netfilter/ipt_SYNPROXY.c | 1 + net/ipv6/netfilter/ip6t_SYNPROXY.c | 1 + 2 files changed, 2 insertions(+) diff --git a/net/ipv4/netfilter/ipt_SYNPROXY.c b/net/ipv4/netfilter/ipt_SYNPROXY.c index 01cffea..f13bd91 100644 --- a/net/ipv4/netfilter/ipt_SYNPROXY.c +++ b/net/ipv4/netfilter/ipt_SYNPROXY.c @@ -244,6 +244,7 @@ synproxy_recv_client_ack(const struct synproxy_net *snet, this_cpu_inc(snet->stats->cookie_valid); opts->mss = mss; + opts->options |= XT_SYNPROXY_OPT_MSS; if (opts->options & XT_SYNPROXY_OPT_TIMESTAMP) synproxy_check_timestamp_cookie(opts); diff --git a/net/ipv6/netfilter/ip6t_SYNPROXY.c b/net/ipv6/netfilter/ip6t_SYNPROXY.c index bf9f612..f78f41a 100644 --- a/net/ipv6/netfilter/ip6t_SYNPROXY.c +++ b/net/ipv6/netfilter/ip6t_SYNPROXY.c @@ -259,6 +259,7 @@ synproxy_recv_client_ack(const struct synproxy_net *snet, this_cpu_inc(snet->stats->cookie_valid); opts->mss = mss; + opts->options |= XT_SYNPROXY_OPT_MSS; if (opts->options & XT_SYNPROXY_OPT_TIMESTAMP) synproxy_check_timestamp_cookie(opts); -- 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