tcp: don't annotate mark on control socket from tcp_v6_send_response()

commit 92e55f412cffd016cc245a74278cb4d7b89bb3bc upstream.

Unlike ipv4, this control socket is shared by all cpus so we cannot use
it as scratchpad area to annotate the mark that we pass to ip6_xmit().

Add a new parameter to ip6_xmit() to indicate the mark. The SCTP socket
family caches the flowi6 structure in the sctp_transport structure, so
we cannot use to carry the mark unless we later on reset it back, which
I discarded since it looks ugly to me.

Fixes: bf99b4ded5f8 ("tcp: fix mark propagation with fwmark_reflect enabled")
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 2 insertions, 3 deletions

diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 5200c676fc72..667396536feb 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -467,7 +467,7 @@ static int tcp_v6_send_synack(const struct sock *sk, struct dst_entry *dst,
                 opt = ireq->ipv6_opt;
                 if (!opt)
                         opt = rcu_dereference(np->opt);
-                err = ip6_xmit(sk, skb, fl6, opt, np->tclass);
+                err = ip6_xmit(sk, skb, fl6, sk->sk_mark, opt, np->tclass);
                 rcu_read_unlock();
                 err = net_xmit_eval(err);
         }
@@ -837,8 +837,7 @@ static void tcp_v6_send_response(const struct sock *sk, struct sk_buff *skb, u32
         dst = ip6_dst_lookup_flow(ctl_sk, &fl6, NULL);
         if (!IS_ERR(dst)) {
                 skb_dst_set(buff, dst);
-                ctl_sk->sk_mark = fl6.flowi6_mark;
-                ip6_xmit(ctl_sk, buff, &fl6, NULL, tclass);
+                ip6_xmit(ctl_sk, buff, &fl6, fl6.flowi6_mark, NULL, tclass);
                 TCP_INC_STATS(net, TCP_MIB_OUTSEGS);
                 if (rst)
                         TCP_INC_STATS(net, TCP_MIB_OUTRSTS);