snmp plugin: Issue an error if an instance name is empty.

diff --git a/src/snmp.c b/src/snmp.c
index 07465dd..2026e8b 100644 (file)
--- a/src/snmp.c
+++ b/src/snmp.c
@@ -863,6 +863,14 @@ static int csnmp_instance_list_add (csnmp_list_instances_t **head,
     if (instance_len > vb->val_len)
       instance_len = vb->val_len;
 
+    if (instance_len < 1)
+    {
+      ERROR ("snmp plugin: csnmp_instance_list_add: instance_len = %zu, "
+         "which is less than one.", instance_len);
+      sfree (il);
+      return (-1);
+    }
+
     sstrncpy (il->instance, (char *) ((vb->type == ASN_OCTET_STR)
          ? vb->val.string
          : vb->val.bitstring),