From 00483690552c5fb6aa30bf3acb75b0ee89b4c0fd Mon Sep 17 00:00:00 2001 From: Jon Maxwell Date: Thu, 10 May 2018 16:53:51 +1000 Subject: tcp: Add mark for TIMEWAIT sockets This version has some suggestions by Eric Dumazet: - Use a local variable for the mark in IPv6 instead of ctl_sk to avoid SMP races. - Use the more elegant "IP4_REPLY_MARK(net, skb->mark) ?: sk->sk_mark" statement. - Factorize code as sk_fullsock() check is not necessary. Aidan McGurn from Openwave Mobility systems reported the following bug: "Marked routing is broken on customer deployment. Its effects are large increase in Uplink retransmissions caused by the client never receiving the final ACK to their FINACK - this ACK misses the mark and routes out of the incorrect route." Currently marks are added to sk_buffs for replies when the "fwmark_reflect" sysctl is enabled. But not for TW sockets that had sk->sk_mark set via setsockopt(SO_MARK..). Fix this in IPv4/v6 by adding tw->tw_mark for TIME_WAIT sockets. Copy the the original sk->sk_mark in __inet_twsk_hashdance() to the new tw->tw_mark location. Then progate this so that the skb gets sent with the correct mark. Do the same for resets. Give the "fwmark_reflect" sysctl precedence over sk->sk_mark so that netfilter rules are still honored. Signed-off-by: Jon Maxwell Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller --- net/ipv6/tcp_ipv6.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'net/ipv6/tcp_ipv6.c') diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 6d664d83cd16..7d47c2b550a9 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -803,6 +803,7 @@ static void tcp_v6_send_response(const struct sock *sk, struct sk_buff *skb, u32 unsigned int tot_len = sizeof(struct tcphdr); struct dst_entry *dst; __be32 *topt; + __u32 mark = 0; if (tsecr) tot_len += TCPOLEN_TSTAMP_ALIGNED; @@ -871,7 +872,10 @@ static void tcp_v6_send_response(const struct sock *sk, struct sk_buff *skb, u32 fl6.flowi6_oif = oif; } - fl6.flowi6_mark = IP6_REPLY_MARK(net, skb->mark); + if (sk) + mark = (sk->sk_state == TCP_TIME_WAIT) ? + inet_twsk(sk)->tw_mark : sk->sk_mark; + fl6.flowi6_mark = IP6_REPLY_MARK(net, skb->mark) ?: mark; fl6.fl6_dport = t1->dest; fl6.fl6_sport = t1->source; fl6.flowi6_uid = sock_net_uid(net, sk && sk_fullsock(sk) ? sk : NULL); -- cgit 1.4.1