From: Otto <otto.moerbeek@open-xchange.com>
Date: Fri, 22 Oct 2021 09:19:59 +0000 (+0200)
Subject: Avoid Undefined Behaviour by making sure the packet size is at least
X-Git-Tag: rec-4.6.0-beta1~45^2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=refs%2Fpull%2F10872%2Fhead;p=thirdparty%2Fpdns.git

Avoid Undefined Behaviour by making sure the packet size is at least
the size passed in
---

diff --git a/pdns/test-dnsname_cc.cc b/pdns/test-dnsname_cc.cc
index 6c88a8baaf..98aed701bf 100644
--- a/pdns/test-dnsname_cc.cc
+++ b/pdns/test-dnsname_cc.cc
@@ -388,28 +388,28 @@ BOOST_AUTO_TEST_CASE(test_hashContainer) {
 
 
 BOOST_AUTO_TEST_CASE(test_QuestionHash) {
-  vector<unsigned char> packet;
+  vector<unsigned char> packet(sizeof(dnsheader));
   reportBasicTypes();
 
   // A return init case
   BOOST_CHECK_EQUAL(hashQuestion(packet.data(), sizeof(dnsheader), 0xffU), 0xffU);
 
   // We subtract 4 from the packet sizes since DNSPacketWriter adds a type and a class
-  // W eexcpect the hash of the root to bne unequal to the burtle init value
+  // We expect the hash of the root to be unequal to the burtle init value
   DNSPacketWriter dpw0(packet, DNSName("."), QType::AAAA);
   BOOST_CHECK(hashQuestion(packet.data(), packet.size() - 4, 0xffU) != 0xffU);
 
-  // A truncated buffer
+  // A truncated buffer should return the init value
   DNSPacketWriter dpw1(packet, DNSName("."), QType::AAAA);
   BOOST_CHECK_EQUAL(hashQuestion(packet.data(), packet.size() - 5, 0xffU), 0xffU);
 
   DNSPacketWriter dpw2(packet, DNSName("www.ds9a.nl."), QType::AAAA);
-  // Let's make an invalid name by overwriting the length of the second label just outside
+  // Let's make an invalid name by overwriting the length of the second label just outside the buffer
   packet[sizeof(dnsheader) + 4] = 8;
   BOOST_CHECK_EQUAL(hashQuestion(packet.data(), packet.size() - 4, 0xffU), 0xffU);
 
   DNSPacketWriter dpw3(packet, DNSName("www.ds9a.nl."), QType::AAAA);
-  // Let's make an invalid name by overwriting the length of the second label way outside
+  // Let's make an invalid name by overwriting the length of the second label way outside the buffer
   packet[sizeof(dnsheader) + 4] = 0xff;
   BOOST_CHECK_EQUAL(hashQuestion(packet.data(), packet.size() - 4, 0xffU), 0xffU);