From: Otto Moerbeek <otto.moerbeek@open-xchange.com>
Date: Wed, 6 Nov 2019 10:15:30 +0000 (+0100)
Subject: Avoid mthread race when using the set of rootNSZones.
X-Git-Tag: dnsdist-1.4.0~18^2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=refs%2Fpull%2F8510%2Fhead;p=thirdparty%2Fpdns.git

Avoid mthread race when using the set of rootNSZones.
---

diff --git a/pdns/reczones.cc b/pdns/reczones.cc
index c811b0c989..cade82750a 100644
--- a/pdns/reczones.cc
+++ b/pdns/reczones.cc
@@ -127,7 +127,11 @@ void primeRootNSZones(bool dnssecmode)
     sr.setDoDNSSEC(true);
     sr.setDNSSECValidationRequested(true);
   }
-  for (const auto & qname: t_rootNSZones) {
+
+  // beginResolve() can yield to another mthread that could trigger t_rootNSZones updates,
+  // so make a local copy
+  set<DNSName> copy(t_rootNSZones);  
+  for (const auto & qname: copy) {
     t_RC->doWipeCache(qname, false, QType::NS);
     vector<DNSRecord> ret;
     sr.beginResolve(qname, QType(QType::NS), QClass::IN, ret);