From 2c75693e72abe792e0bf9b55c5f8f443fa220160 Mon Sep 17 00:00:00 2001
From: Otto Moerbeek <otto.moerbeek@open-xchange.com>
Date: Wed, 3 Apr 2019 14:10:22 +0200
Subject: [PATCH] Fix fatal exception on unparseable slave addresses. Backport
 of https://github.com/PowerDNS/pdns/pull/7662

---
 pdns/communicator.hh       | 24 +++++++++++++++++++-----
 pdns/mastercommunicator.cc |  2 +-
 pdns/tcpreceiver.cc        |  2 +-
 3 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/pdns/communicator.hh b/pdns/communicator.hh
index a7f95b81d..f646b2226 100644
--- a/pdns/communicator.hh
+++ b/pdns/communicator.hh
@@ -244,18 +244,32 @@ private:
 class FindNS
 {
 public:
-  vector<string> lookup(const DNSName &name, UeberBackend *b)
+  vector<string> lookup(const DNSName &name, UeberBackend *b, const DNSName& zone)
   {
     vector<string> addresses;
 
     this->resolve_name(&addresses, name);
     
     if(b) {
-        b->lookup(QType(QType::ANY),name);
-        DNSZoneRecord rr;
-        while(b->get(rr))
-          if(rr.dr.d_type == QType::A || rr.dr.d_type==QType::AAAA)
+      b->lookup(QType(QType::ANY),name);
+      while (true) {
+        try {
+          DNSZoneRecord rr;
+          if (!b->get(rr))
+            break;
+          if (rr.dr.d_type == QType::A || rr.dr.d_type == QType::AAAA)
             addresses.push_back(rr.dr.d_content->getZoneRepresentation());   // SOL if you have a CNAME for an NS
+        }
+        // After an exception, b can be inconsistent so break
+        catch (PDNSException &ae) {
+          L << Logger::Error << "Could not lookup address for nameserver " << name << " in zone " << zone << ", cannot notify: " << ae.reason << endl;
+          break;
+        }
+        catch (std::exception &e) {
+          L << Logger::Error << "Could not lookup address for nameserver " << name << " in zone " << zone << ", cannot notify: " << e.what() << endl;
+          break;
+        }
+      }
     }
     return addresses;
   }
diff --git a/pdns/mastercommunicator.cc b/pdns/mastercommunicator.cc
index 456957a80..8be9ebad9 100644
--- a/pdns/mastercommunicator.cc
+++ b/pdns/mastercommunicator.cc
@@ -56,7 +56,7 @@ void CommunicatorClass::queueNotifyDomain(const DomainInfo& di, UeberBackend* B)
       nsset.insert(getRR<NSRecordContent>(rr.dr)->getNS().toString());
 
     for(set<string>::const_iterator j=nsset.begin();j!=nsset.end();++j) {
-      vector<string> nsips=fns.lookup(DNSName(*j), B);
+      vector<string> nsips=fns.lookup(DNSName(*j), B, di.zone);
       if(nsips.empty())
         L<<Logger::Warning<<"Unable to queue notification of domain '"<<di.zone<<"': nameservers do not resolve!"<<endl;
       else
diff --git a/pdns/tcpreceiver.cc b/pdns/tcpreceiver.cc
index d2491f79f..584dbae5b 100644
--- a/pdns/tcpreceiver.cc
+++ b/pdns/tcpreceiver.cc
@@ -491,7 +491,7 @@ bool TCPNameserver::canDoAXFR(shared_ptr<DNSPacket> q)
         while(B->get(rr)) 
           nsset.insert(DNSName(rr.content));
         for(const auto & j: nsset) {
-          vector<string> nsips=fns.lookup(j, s_P->getBackend());
+          vector<string> nsips=fns.lookup(j, s_P->getBackend(),q->qdomain);
           for(vector<string>::const_iterator k=nsips.begin();k!=nsips.end();++k) {
             // cerr<<"got "<<*k<<" from AUTO-NS"<<endl;
             if(*k == q->getRemote().toString())
-- 
2.40.0