[NETNS]: Use TCP control socket from a correct namespace.

Signed-off-by: NDenis V.Lunev <den@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv4/tcp_ipv4.c

@@ -88,9 +88,6 @@ int sysctl_tcp_low_latency __read_mostly;
 /* Check TCP sequence numbers in ICMP packets. */
 #define ICMP_MIN_LENGTH 8
 
-/* Socket used for sending RSTs */
-static struct sock *tcp_sock __read_mostly;
-
 void tcp_v4_send_check(struct sock *sk, int len, struct sk_buff *skb);
 
 #ifdef CONFIG_TCP_MD5SIG
@@ -598,7 +595,8 @@ static void tcp_v4_send_reset(struct sock *sk, struct sk_buff *skb)
 				      sizeof(struct tcphdr), IPPROTO_TCP, 0);
 	arg.csumoffset = offsetof(struct tcphdr, check) / 2;
 
-	ip_send_reply(tcp_sock, skb, &arg, arg.iov[0].iov_len);
+	ip_send_reply(dev_net(skb->dst->dev)->ipv4.tcp_sock, skb,
+		      &arg, arg.iov[0].iov_len);
 
 	TCP_INC_STATS_BH(TCP_MIB_OUTSEGS);
 	TCP_INC_STATS_BH(TCP_MIB_OUTRSTS);
@@ -693,7 +691,8 @@ static void tcp_v4_send_ack(struct tcp_timewait_sock *twsk,
 	if (twsk)
 		arg.bound_dev_if = twsk->tw_sk.tw_bound_dev_if;
 
-	ip_send_reply(tcp_sock, skb, &arg, arg.iov[0].iov_len);
+	ip_send_reply(dev_net(skb->dev)->ipv4.tcp_sock, skb,
+		      &arg, arg.iov[0].iov_len);
 
 	TCP_INC_STATS_BH(TCP_MIB_OUTSEGS);
 }
@@ -2509,7 +2508,6 @@ void __init tcp_v4_init(void)
 {
 	if (register_pernet_device(&tcp_sk_ops))
 		panic("Failed to create the TCP control socket.\n");
-	tcp_sock = init_net.ipv4.tcp_sock;
 }
 
 EXPORT_SYMBOL(ipv4_specific);