diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 480373c960cd..bae7231096cf 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -5227,6 +5227,8 @@ static void __tcp_ack_snd_check(struct sock *sk, int ofo_possible)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
 	unsigned long rtt, delay;
+	struct sock *meta_sk = mptcp(tp) ? mptcp_meta_sk(sk) : sk;
+	struct tcp_sock *meta_tp = tcp_sk(meta_sk);
 
 	/* More than one full frame received... */
 	if (((tp->rcv_nxt - tp->rcv_wup) > inet_csk(sk)->icsk_ack.rcv_mss &
@@ -5268,6 +5268,6 @@
 	      * we have not received enough bytes to satisfy the condition.
 	      */
-	    (tp->rcv_nxt - tp->copied_seq < sk->sk_rcvlowat ||
+	    (meta_tp->rcv_nxt - meta_tp->copied_seq < meta_sk->sk_rcvlowat ||
 	     tp->ops->__select_window(sk) >= tp->rcv_wnd)) ||
 	    /* We ACK each frame or... */
 	    tcp_in_quickack_mode(sk) ||