From: Remi Gacogne <remi.gacogne@powerdns.com>
Date: Fri, 22 Nov 2019 08:54:06 +0000 (+0100)
Subject: dnsdist: Make sure that setConsistentHashingBalancingFactor() >= 0
X-Git-Tag: auth-4.3.0-beta1~47^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=80ee5144d23acfdf115b30452c59ac25fdb34a15;p=thirdparty%2Fpdns.git

dnsdist: Make sure that setConsistentHashingBalancingFactor() >= 0
---

diff --git a/pdns/dnsdist-lua.cc b/pdns/dnsdist-lua.cc
index 251a071f59..4976e3a667 100644
--- a/pdns/dnsdist-lua.cc
+++ b/pdns/dnsdist-lua.cc
@@ -1593,7 +1593,14 @@ void setupLuaConfig(bool client)
 
   g_lua.writeFunction("setConsistentHashingBalancingFactor", [](double factor) {
       setLuaSideEffect();
-      g_consistentHashBalancingFactor = factor;
+      if (factor >= 0) {
+        g_consistentHashBalancingFactor = factor;
+      }
+      else {
+        errlog("Invalid value passed to setConsistentHashingBalancingFactor()!");
+        g_outputBuffer="Invalid value passed to setConsistentHashingBalancingFactor()!\n";
+        return;
+      }
     });
 
   g_lua.writeFunction("setRingBuffersSize", [](size_t capacity, boost::optional<size_t> numberOfShards) {
diff --git a/pdns/dnsdist.cc b/pdns/dnsdist.cc
index 4c3bb2cc52..71066f1d0c 100644
--- a/pdns/dnsdist.cc
+++ b/pdns/dnsdist.cc
@@ -896,7 +896,7 @@ shared_ptr<DownstreamState> chashed(const NumberedServerVector& servers, const D
   shared_ptr<DownstreamState> ret = nullptr, first = nullptr;
 
   double targetLoad = std::numeric_limits<double>::max();
-  if (g_consistentHashBalancingFactor != 0) {
+  if (g_consistentHashBalancingFactor > 0) {
     /* we start with one, representing the query we are currently handling */
     double currentLoad = 1;
     for (const auto& pair : servers) {