diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 91a8cfd..44c1e93 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -687,14 +687,14 @@
 	inet_twsk_put(tw);
 }
 
-static void tcp_v4_reqsk_send_ack(struct sk_buff *skb,
+static void tcp_v4_reqsk_send_ack(struct sock *sk, struct sk_buff *skb,
 				  struct request_sock *req)
 {
 	tcp_v4_send_ack(skb, tcp_rsk(req)->snt_isn + 1,
 			tcp_rsk(req)->rcv_isn + 1, req->rcv_wnd,
 			req->ts_recent,
 			0,
-			tcp_v4_md5_do_lookup(skb->sk, ip_hdr(skb)->daddr));
+			tcp_v4_md5_do_lookup(sk, ip_hdr(skb)->daddr));
 }
 
 /*