diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index a9329b072b94b..4ccfec4bb6248 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -237,8 +237,9 @@ static void tcp_measure_rcv_mss(struct sock *sk, const struct sk_buff *skb)
 		 * when we update icsk_ack.rcv_mss.
 		 */
 		if (unlikely(len != icsk->icsk_ack.rcv_mss)) {
-			u64 val = __tcp_space_from_win(skb->truesize, skb->len);
+			u64 val = (u64)skb->len << TCP_RMEM_TO_WIN_SCALE;
 
+			do_div(val, skb->truesize);
 			tcp_sk(sk)->scaling_ratio = val ? val : 1;
 		}
 		icsk->icsk_ack.rcv_mss = min_t(unsigned int, len,