diff --git a/openbsc/src/libcommon/gsm_subscriber_base.c b/openbsc/src/libcommon/gsm_subscriber_base.c
index 50f4118..1f98cc6 100644
--- a/openbsc/src/libcommon/gsm_subscriber_base.c
+++ b/openbsc/src/libcommon/gsm_subscriber_base.c
@@ -43,6 +43,9 @@
 
 char *subscr_name(struct gsm_subscriber *subscr)
 {
+	if (!subscr)
+		return "unknown";
+
 	if (strlen(subscr->name))
 		return subscr->name;