diff --git a/include/linux/sock_diag.h b/include/linux/sock_diag.h
index 46cca4c06848..b5ad7d35a636 100644
--- a/include/linux/sock_diag.h
+++ b/include/linux/sock_diag.h
@@ -19,7 +19,7 @@ void sock_diag_unregister(const struct sock_diag_handler *h);
 void sock_diag_register_inet_compat(int (*fn)(struct sk_buff *skb, struct nlmsghdr *nlh));
 void sock_diag_unregister_inet_compat(int (*fn)(struct sk_buff *skb, struct nlmsghdr *nlh));
 
-int sock_diag_check_cookie(void *sk, __u32 *cookie);
+int sock_diag_check_cookie(void *sk, const __u32 *cookie);
 void sock_diag_save_cookie(void *sk, __u32 *cookie);
 
 int sock_diag_put_meminfo(struct sock *sk, struct sk_buff *skb, int attr);
diff --git a/net/core/sock_diag.c b/net/core/sock_diag.c
index ad704c757bb4..96e70ee05a8d 100644
--- a/net/core/sock_diag.c
+++ b/net/core/sock_diag.c
@@ -13,7 +13,7 @@ static const struct sock_diag_handler *sock_diag_handlers[AF_MAX];
 static int (*inet_rcv_compat)(struct sk_buff *skb, struct nlmsghdr *nlh);
 static DEFINE_MUTEX(sock_diag_table_mutex);
 
-int sock_diag_check_cookie(void *sk, __u32 *cookie)
+int sock_diag_check_cookie(void *sk, const __u32 *cookie)
 {
 	if ((cookie[0] != INET_DIAG_NOCOOKIE ||
 	     cookie[1] != INET_DIAG_NOCOOKIE) &&