[TCP]: When in SYN-SENT, initialize metrics after move to established state.

net/ipv4/tcp_input.c

@@ -3694,6 +3694,13 @@ static int tcp_rcv_synsent_state_process(struct sock *sk, struct sk_buff *skb,
 		tcp_sync_mss(sk, tp->pmtu_cookie);
 		tcp_initialize_rcv_mss(sk);
 
+		/* Remember, tcp_poll() does not lock socket!
+		 * Change state from SYN-SENT only after copied_seq
+		 * is initialized. */
+		tp->copied_seq = tp->rcv_nxt;
+		mb();
+		tcp_set_state(sk, TCP_ESTABLISHED);
+
 		/* Make sure socket is routed, for correct metrics.  */
 		tp->af_specific->rebuild_header(sk);
 
@@ -3714,13 +3721,6 @@ static int tcp_rcv_synsent_state_process(struct sock *sk, struct sk_buff *skb,
 		else
 			tp->pred_flags = 0;
 
-		/* Remember, tcp_poll() does not lock socket!
-		 * Change state from SYN-SENT only after copied_seq
-		 * is initialized. */
-		tp->copied_seq = tp->rcv_nxt;
-		mb();
-		tcp_set_state(sk, TCP_ESTABLISHED);
-
 		if (!sock_flag(sk, SOCK_DEAD)) {
 			sk->sk_state_change(sk);
 			sk_wake_async(sk, 0, POLL_OUT);