diff --git a/tests/lapd/lapd_test.c b/tests/lapd/lapd_test.c
index 18ea1dc..e322314 100644
--- a/tests/lapd/lapd_test.c
+++ b/tests/lapd/lapd_test.c
@@ -51,7 +51,8 @@
 {
 	struct msgb *msg = msgb_alloc_headroom(4096, 128, "data");
 	msg->l3h = msgb_put(msg, len);
-	memcpy(msg->l3h, data, len);
+	if (data && len)
+		memcpy(msg->l3h, data, len);
 	return msg;
 }