diff --git a/include/net/inet_connection_sock.h b/include/net/inet_connection_sock.h
index 0320bbb..00c3ced 100644
--- a/include/net/inet_connection_sock.h
+++ b/include/net/inet_connection_sock.h
@@ -266,7 +266,7 @@
 			   const struct inet_bind_bucket *tb, bool relax);
 int inet_csk_get_port(struct sock *sk, unsigned short snum);
 
-struct dst_entry *inet_csk_route_req(struct sock *sk, struct flowi4 *fl4,
+struct dst_entry *inet_csk_route_req(const struct sock *sk, struct flowi4 *fl4,
 				     const struct request_sock *req);
 struct dst_entry *inet_csk_route_child_sock(struct sock *sk, struct sock *newsk,
 					    const struct request_sock *req);
diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c
index 1349571..ad087c1 100644
--- a/net/ipv4/inet_connection_sock.c
+++ b/net/ipv4/inet_connection_sock.c
@@ -408,7 +408,7 @@
 }
 EXPORT_SYMBOL(inet_csk_reset_keepalive_timer);
 
-struct dst_entry *inet_csk_route_req(struct sock *sk,
+struct dst_entry *inet_csk_route_req(const struct sock *sk,
 				     struct flowi4 *fl4,
 				     const struct request_sock *req)
 {