diff --git a/openbsc/src/libmsc/smpp_openbsc.c b/openbsc/src/libmsc/smpp_openbsc.c
index ff5ab40..b17222f 100644
--- a/openbsc/src/libmsc/smpp_openbsc.c
+++ b/openbsc/src/libmsc/smpp_openbsc.c
@@ -114,12 +114,13 @@
 		}
 		sms_msg = t->value.octet;
 		sms_msg_len = t->length;
-	} else if (submit->sm_length) {
+	} else if (submit->sm_length > 0 && submit->sm_length < 255) {
 		sms_msg = submit->short_message;
 		sms_msg_len = submit->sm_length;
 	} else {
-		sms_msg = NULL;
-		sms_msg_len = 0;
+		LOGP(DLSMS, LOGL_ERROR,
+			"SMPP neither message payload nor valid sm_length.\n");
+		return ESME_RINVPARLEN;
 	}
 
 	sms = sms_alloc();