--- display.c.orig	Mon Aug 24 05:51:48 1998
+++ display.c	Tue Apr  5 22:44:25 2016
@@ -389,8 +389,8 @@ truncated-udp: wrong ip hdrlen");
 				te.sport = ntohs(((struct udphdr *)cp)->uh_sport);
 				te.dport = ntohs(((struct udphdr *)cp)->uh_dport);
 			} else if (ip->ip_p == IPPROTO_ICMP) {
-				if (cp + sizeof(struct icmp) > snapend ||
-				    iplen - hlen < sizeof(struct icmp)) {
+				if (cp + 4 > snapend ||
+				    iplen - hlen < 4) {
 					mvprintw(LINES-1, err_pos, "\
 truncated-icmp: wrong ip hdrlen");
 					clrtoeol();