From 32fc3b0370c1992d1f81e2213d51d773180a0c61 Mon Sep 17 00:00:00 2001
From: Remi Gacogne <remi.gacogne@powerdns.com>
Date: Fri, 23 Mar 2018 11:16:03 +0100
Subject: [PATCH] ixfr: Get rid of a VLA (and two copies) in getIXFRDeltas()

---
 pdns/ixfr.cc | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/pdns/ixfr.cc b/pdns/ixfr.cc
index 8d02a8bf5..56a69c1df 100644
--- a/pdns/ixfr.cc
+++ b/pdns/ixfr.cc
@@ -169,6 +169,7 @@ vector<pair<vector<DNSRecord>, vector<DNSRecord> > > getIXFRDeltas(const ComboAd
   vector<DNSRecord> records;
   size_t receivedBytes = 0;
   int8_t ixfrInProgress = -2;
+  std::string reply;
 
   for(;;) {
     // IXFR end
@@ -186,18 +187,18 @@ vector<pair<vector<DNSRecord>, vector<DNSRecord> > > getIXFRDeltas(const ComboAd
     if (maxReceivedBytes > 0 && (maxReceivedBytes - receivedBytes) < (size_t) len)
       throw std::runtime_error("Reached the maximum number of received bytes in an IXFR delta for zone '"+zone.toLogString()+"' from master "+master.toStringWithPort());
 
-    char reply[len]; 
-    readn2(s.getHandle(), reply, len);
+    reply.resize(len);
+    readn2(s.getHandle(), &reply.at(0), len);
     receivedBytes += len;
 
-    MOADNSParser mdp(false, string(reply, len));
+    MOADNSParser mdp(false, reply);
     if(mdp.d_header.rcode) 
       throw std::runtime_error("Got an error trying to IXFR zone '"+zone.toLogString()+"' from master '"+master.toStringWithPort()+"': "+RCode::to_s(mdp.d_header.rcode));
 
     //    cout<<"Got a response, rcode: "<<mdp.d_header.rcode<<", got "<<mdp.d_answers.size()<<" answers"<<endl;
 
     if(!tt.algo.empty()) { // TSIG verify message
-      tsigVerifier.check(std::string(reply, len), mdp);
+      tsigVerifier.check(reply, mdp);
     }
 
     for(auto& r: mdp.d_answers) {
-- 
2.40.0