From 13dacc771accd53b087b2b14060afacaf2969802 Mon Sep 17 00:00:00 2001
From: Remi Gacogne <remi.gacogne@powerdns.com>
Date: Mon, 16 Apr 2018 17:12:27 +0200
Subject: [PATCH] rec: Stop the obsolete RPZ threads after a Lua configuration
 reload

---
 pdns/rec-lua-conf.cc |  2 +-
 pdns/rec-lua-conf.hh |  4 ++--
 pdns/rpzloader.cc    | 13 +++++++++++--
 pdns/rpzloader.hh    |  2 +-
 4 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/pdns/rec-lua-conf.cc b/pdns/rec-lua-conf.cc
index 2098fbfa0..5f8d1d2eb 100644
--- a/pdns/rec-lua-conf.cc
+++ b/pdns/rec-lua-conf.cc
@@ -199,7 +199,7 @@ void loadRecursorLuaConfig(const std::string& fname, bool checkOnly)
 
       try {
           if (!checkOnly) {
-            std::thread t(RPZIXFRTracker, master, defpol, maxTTL, zoneIdx, tt, maxReceivedXFRMBytes * 1024 * 1024, localAddress, zone, axfrTimeout);
+            std::thread t(RPZIXFRTracker, master, defpol, maxTTL, zoneIdx, tt, maxReceivedXFRMBytes * 1024 * 1024, localAddress, zone, axfrTimeout, lci.generation);
             t.detach();
           }
       }
diff --git a/pdns/rec-lua-conf.hh b/pdns/rec-lua-conf.hh
index 2d3ef4185..a502a2093 100644
--- a/pdns/rec-lua-conf.hh
+++ b/pdns/rec-lua-conf.hh
@@ -43,11 +43,11 @@ public:
   DNSFilterEngine dfe;
   map<DNSName,dsmap_t> dsAnchors;
   map<DNSName,std::string> negAnchors;
+  ProtobufExportConfig protobufExportConfig;
+  ProtobufExportConfig outgoingProtobufExportConfig;
   /* we need to increment this every time the configuration
      is reloaded, so we know if we need to reload the protobuf
      remote loggers */
-  ProtobufExportConfig protobufExportConfig;
-  ProtobufExportConfig outgoingProtobufExportConfig;
   uint64_t generation{0};
   uint8_t protobufMaskV4{32};
   uint8_t protobufMaskV6{128};
diff --git a/pdns/rpzloader.cc b/pdns/rpzloader.cc
index 0473ceac1..79aa90dd7 100644
--- a/pdns/rpzloader.cc
+++ b/pdns/rpzloader.cc
@@ -283,7 +283,7 @@ static void setRPZZoneNewState(const std::string& zone, uint32_t serial, uint64_
   stats->d_numberOfRecords = numberOfRecords;
 }
 
-void RPZIXFRTracker(const ComboAddress& master, boost::optional<DNSFilterEngine::Policy> defpol, uint32_t maxTTL, size_t zoneIdx, const TSIGTriplet& tt, size_t maxReceivedBytes, const ComboAddress& localAddress, std::shared_ptr<DNSFilterEngine::Zone> zone, const uint16_t axfrTimeout)
+void RPZIXFRTracker(const ComboAddress& master, boost::optional<DNSFilterEngine::Policy> defpol, uint32_t maxTTL, size_t zoneIdx, const TSIGTriplet& tt, size_t maxReceivedBytes, const ComboAddress& localAddress, std::shared_ptr<DNSFilterEngine::Zone> zone, const uint16_t axfrTimeout, uint64_t configGeneration)
 {
   uint32_t refresh = zone->getRefresh();
   DNSName zoneName = zone->getDomain();
@@ -317,12 +317,22 @@ void RPZIXFRTracker(const ComboAddress& master, boost::optional<DNSFilterEngine:
     }
   }
 
+  auto luaconfsLocal = g_luaconfs.getLocal();
+
   for(;;) {
     DNSRecord dr;
     dr.d_content=sr;
 
     sleep(refresh);
 
+    if (luaconfsLocal->generation != configGeneration) {
+      /* the configuration has been reloaded, meaning that a new thread
+         has been started to handle that zone and we are now obsolete.
+      */
+      g_log<<Logger::Info<<"A more recent configuration has been found, stopping the existing RPZ update thread for "<<zoneName<<endl;
+      return;
+    }
+
     g_log<<Logger::Info<<"Getting IXFR deltas for "<<zoneName<<" from "<<master.toStringWithPort()<<", our serial: "<<getRR<SOARecordContent>(dr)->d_st.serial<<endl;
     vector<pair<vector<DNSRecord>, vector<DNSRecord> > > deltas;
 
@@ -341,7 +351,6 @@ void RPZIXFRTracker(const ComboAddress& master, boost::optional<DNSFilterEngine:
       continue;
     g_log<<Logger::Info<<"Processing "<<deltas.size()<<" delta"<<addS(deltas)<<" for RPZ "<<zoneName<<endl;
 
-    auto luaconfsLocal = g_luaconfs.getLocal();
     const std::shared_ptr<DNSFilterEngine::Zone> oldZone = luaconfsLocal->dfe.getZone(zoneIdx);
     /* we need to make a _full copy_ of the zone we are going to work on */
     std::shared_ptr<DNSFilterEngine::Zone> newZone = std::make_shared<DNSFilterEngine::Zone>(*oldZone);
diff --git a/pdns/rpzloader.hh b/pdns/rpzloader.hh
index ac47bfb22..465bc8765 100644
--- a/pdns/rpzloader.hh
+++ b/pdns/rpzloader.hh
@@ -29,7 +29,7 @@ extern bool g_logRPZChanges;
 void loadRPZFromFile(const std::string& fname, std::shared_ptr<DNSFilterEngine::Zone> zone, boost::optional<DNSFilterEngine::Policy> defpol, uint32_t maxTTL);
 std::shared_ptr<SOARecordContent> loadRPZFromServer(const ComboAddress& master, const DNSName& zoneName, std::shared_ptr<DNSFilterEngine::Zone> zone, boost::optional<DNSFilterEngine::Policy> defpol, uint32_t maxTTL, const TSIGTriplet& tt, size_t maxReceivedBytes, const ComboAddress& localAddress, const uint16_t axfrTimeout);
 void RPZRecordToPolicy(const DNSRecord& dr, std::shared_ptr<DNSFilterEngine::Zone> zone, bool addOrRemove, boost::optional<DNSFilterEngine::Policy> defpol, uint32_t maxTTL);
-void RPZIXFRTracker(const ComboAddress& master, boost::optional<DNSFilterEngine::Policy> defpol, uint32_t maxTTL, size_t polZone, const TSIGTriplet &tt, size_t maxReceivedBytes, const ComboAddress& localAddress, std::shared_ptr<DNSFilterEngine::Zone> zone, uint16_t axfrTimeout);
+void RPZIXFRTracker(const ComboAddress& master, boost::optional<DNSFilterEngine::Policy> defpol, uint32_t maxTTL, size_t polZone, const TSIGTriplet &tt, size_t maxReceivedBytes, const ComboAddress& localAddress, std::shared_ptr<DNSFilterEngine::Zone> zone, uint16_t axfrTimeout, uint64_t configGeneration);
 
 struct rpzStats
 {
-- 
2.40.0