diff --git a/include/net/tcp.h b/include/net/tcp.h
index 45bc3c6..19f2359 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -461,7 +461,7 @@
 int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb);
 int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);
 int tcp_connect(struct sock *sk);
-struct sk_buff *tcp_make_synack(struct sock *sk, struct dst_entry *dst,
+struct sk_buff *tcp_make_synack(const struct sock *sk, struct dst_entry *dst,
 				struct request_sock *req,
 				struct tcp_fastopen_cookie *foc);
 int tcp_disconnect(struct sock *sk, int flags);