--- a/sys/netgraph7/lmi/ng_lmi.c
+++ b/sys/netgraph7/lmi/ng_lmi.c
@@ nglmi_checkdata @@
 	packetlen = m->m_len;
+	if (packetlen < LMI_MIN_LENGTH) {	/* the define was unused */
+		log(LOG_WARNING, "nglmi: short packet (%d)\n", packetlen);
+		goto reject;
+	}
 	data = mtod(m, const u_char *);