diff --git a/net/socket.c b/net/socket.c
index 8487bf1..5f3b5a2 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -1948,6 +1948,8 @@
 		ctl_buf = msg_sys->msg_control;
 		ctl_len = msg_sys->msg_controllen;
 	} else if (ctl_len) {
+		BUILD_BUG_ON(sizeof(struct cmsghdr) !=
+			     CMSG_ALIGN(sizeof(struct cmsghdr)));
 		if (ctl_len > sizeof(ctl)) {
 			ctl_buf = sock_kmalloc(sock->sk, ctl_len, GFP_KERNEL);
 			if (ctl_buf == NULL)