--- tcpdump-3.9.1/print-bgp.c.orig	2005-07-06 14:59:51.000000000 +0200
+++ tcpdump-3.9.1/print-bgp.c	2005-07-06 15:00:36.000000000 +0200
@@ -1176,7 +1176,7 @@
 			printf(", no SNPA");
                 }
 
-		while (len - (tptr - pptr) > 0) {
+		while ((tptr - pptr) > 0 &&  len - (tptr - pptr) > 0) {
                     switch (af<<8 | safi) {
                     case (AFNUM_INET<<8 | SAFNUM_UNICAST):
                     case (AFNUM_INET<<8 | SAFNUM_MULTICAST):