diff --git a/openbsc/src/libmgcp/mgcp_protocol.c b/openbsc/src/libmgcp/mgcp_protocol.c
index 2e728cb..18398fc 100644
--- a/openbsc/src/libmgcp/mgcp_protocol.c
+++ b/openbsc/src/libmgcp/mgcp_protocol.c
@@ -447,6 +447,7 @@
 	int i = 0;
 	char *elem, *save = NULL;
 
+	OSMO_ASSERT(data);
 	pdata->trans = "000000";
 
 	for (elem = strtok_r(data, " ", &save); elem;