tcp: fix mark propagation with fwmark_reflect enabled

Otherwise, RST packets generated by the TCP stack for non-existing
sockets always have mark 0.
The mark from the original packet is assigned to the netns_ipv4/6
socket used to send the response so that it can get copied into the
response skb when the socket sends it.

Fixes: e110861f8609 ("net: add a sysctl to reflect the fwmark on replies")
Cc: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: Pau Espin Pedrol <pau.espin@tessares.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index fac275c4810865a5b9b9ca1ac9fc826b8482aa9f..b67719f459537d49d958de9874414ea868c4a8e1 100644 (file)
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -1629,6 +1629,7 @@ void ip_send_unicast_reply(struct sock *sk, struct sk_buff *skb,
        sk->sk_protocol = ip_hdr(skb)->protocol;
        sk->sk_bound_dev_if = arg->bound_dev_if;
        sk->sk_sndbuf = sysctl_wmem_default;
+       sk->sk_mark = fl4.flowi4_mark;
        err = ip_append_data(sk, &fl4, ip_reply_glue_bits, arg->iov->iov_base,
                             len, 0, &ipc, &rt, MSG_DONTWAIT);
        if (unlikely(err)) {

diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 73bc8fc68acdc1ed947bfdb7624b3308a9b70806..2b20622a5824a89cb034a69edd258daa20ff7696 100644 (file)
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -840,6 +840,7 @@ 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);
                TCP_INC_STATS(net, TCP_MIB_OUTSEGS);
                if (rst)