diff --git a/src/radv.c b/src/radv.c
index c69a43e..1a79d99 100644
--- a/src/radv.c
+++ b/src/radv.c
@@ -216,9 +216,9 @@
     lease_ping_reply(&from.sin6_addr, packet, interface); 
   else if ((packet[0] == ND_ROUTER_SOLICIT) && (hoplimit == 255))
   {
+    if (!((sz > 8) && (packet[9] == 0))) {
       inet_ntop(AF_INET6, &from.sin6_addr, daemon->addrbuff, ADDRSTRLEN);
-      if ((!((strncmp(daemon->addrbuff, "::",2)==0) && (packet[8] == ICMP6_OPT_SOURCE_MAC))) ||
-           (!(packet[9] == 0)))
+      if (!((strncmp(daemon->addrbuff, "::",2)==0) && (packet[8] == ICMP6_OPT_SOURCE_MAC)))
     {
       char *mac = "";
       struct dhcp_bridge *bridge, *alias;
@@ -283,6 +283,7 @@
   ts.tv_nsec = tms * 1000000;
   nanosleep(&ts, NULL);
     }
+   }
   }
 }