From 66afeb443b071792fd3979f7266c3bae09472e0b Mon Sep 17 00:00:00 2001
From: bert hubert <bert.hubert@netherlabs.nl>
Date: Fri, 6 Nov 2015 16:04:26 +0100
Subject: [PATCH] don't confuse dnspcap users with incomplete packets

---
 pdns/dnspcap.cc | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/pdns/dnspcap.cc b/pdns/dnspcap.cc
index 5ca85d5ce9..0280d702f7 100644
--- a/pdns/dnspcap.cc
+++ b/pdns/dnspcap.cc
@@ -97,6 +97,10 @@ try
       d_udp=reinterpret_cast<const struct udphdr*>(d_buffer + d_skipMediaHeader + 4 * d_ip->ip_hl);
       d_payload = (unsigned char*)d_udp + sizeof(struct udphdr);
       d_len = ntohs(d_udp->uh_ulen) - sizeof(struct udphdr);
+      if((const char*)d_payload + d_len > d_buffer + d_pheader.caplen) {
+	d_runts++;
+	continue;
+      }
       d_correctpackets++;
       return true;
     }
@@ -104,6 +108,11 @@ try
       d_udp=reinterpret_cast<const struct udphdr*>(d_buffer + d_skipMediaHeader + sizeof(struct ip6_hdr));
       d_payload = (unsigned char*)d_udp + sizeof(struct udphdr);
       d_len = ntohs(d_udp->uh_ulen) - sizeof(struct udphdr);
+      if((const char*)d_payload + d_len > d_buffer + d_pheader.caplen) {
+	d_runts++;
+	continue;
+      }
+
       d_correctpackets++;
       return true;
     }
-- 
2.47.2