diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index cebe9aa918a3..dc151139b5af 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -481,7 +481,7 @@ static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it,
 		/* RFC1323: The window in SYN & SYN/ACK segments
 		 * is never scaled.
 		 */
-		th->window	= htons(tp->rcv_wnd);
+		th->window	= htons(min(tp->rcv_wnd, 65535U));
 	} else {
 		th->window	= htons(tcp_select_window(sk));
 	}
@@ -2160,7 +2160,7 @@ struct sk_buff * tcp_make_synack(struct sock *sk, struct dst_entry *dst,
 	}
 
 	/* RFC1323: The window in SYN & SYN/ACK segments is never scaled. */
-	th->window = htons(req->rcv_wnd);
+	th->window = htons(min(req->rcv_wnd, 65535U));
 
 	TCP_SKB_CB(skb)->when = tcp_time_stamp;
 	tcp_syn_build_options((__be32 *)(th + 1), dst_metric(dst, RTAX_ADVMSS), ireq->tstamp_ok,