(udp_print): sanity check that the length in the udp header is at

least 8 to avoid printing garbage

diff --git a/print-udp.c b/print-udp.c
index ec26fcef02a33f2ea6fa28e63d395e1d52fa8464..ef0266c34609638edde80f0b2035a4b7416e6d95 100644 (file)
--- a/print-udp.c
+++ b/print-udp.c
@@ -21,7 +21,7 @@
 
 #ifndef lint
 static const char rcsid[] =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-udp.c,v 1.74 2000-07-14 02:49:00 guy Exp $ (LBL)";
+    "@(#) $Header: /tcpdump/master/tcpdump/print-udp.c,v 1.75 2000-07-22 23:58:01 assar Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -356,6 +356,13 @@ udp_print(register const u_char *bp, u_int length, register const u_char *bp2)
        sport = ntohs(up->uh_sport);
        dport = ntohs(up->uh_dport);
        ulen = ntohs(up->uh_ulen);
+       if (ulen < 8) {
+               (void)printf("%s > %s: truncated-udplength %d",
+                            ipaddr_string(&ip->ip_src),
+                            ipaddr_string(&ip->ip_dst),
+                            ulen);
+               return;
+       }
        if (packettype) {
                register struct rpc_msg *rp;
                enum msg_type direction;