1 files changed, 31 insertions, 0 deletions
diff --git a/netwerk/dns/nsHostResolver.cpp b/netwerk/dns/nsHostResolver.cpp
index ad28cbb284..b74b974041 100644
--- a/netwerk/dns/nsHostResolver.cpp
+++ b/netwerk/dns/nsHostResolver.cpp
@@ -1490,6 +1490,18 @@ nsHostResolver::LookupStatus nsHostResolver::CompleteLookup(
                               aReason, aTRRRequest, lock);
 }
 
+namespace {
+class NetAddrIPv6FirstComparator {
+ public:
+  static bool Equals(const NetAddr& aLhs, const NetAddr& aRhs) {
+    return aLhs.raw.family == aRhs.raw.family;
+  }
+  static bool LessThan(const NetAddr& aLhs, const NetAddr& aRhs) {
+    return aLhs.raw.family > aRhs.raw.family;
+  }
+};
+}  // namespace
+
 nsHostResolver::LookupStatus nsHostResolver::CompleteLookupLocked(
     nsHostRecord* rec, nsresult status, AddrInfo* aNewRRSet, bool pb,
     const nsACString& aOriginsuffix, TRRSkippedReason aReason,
@@ -1601,6 +1613,16 @@ nsHostResolver::LookupStatus nsHostResolver::CompleteLookupLocked(
       old_addr_info = std::move(newRRSet);
     }
     addrRec->negative = !addrRec->addr_info;
+
+    if (addrRec->addr_info && StaticPrefs::network_dns_preferIPv6() &&
+        addrRec->addr_info->Addresses().Length() > 1 &&
+        addrRec->addr_info->Addresses()[0].IsIPAddrV4()) {
+      // Sort IPv6 addresses first.
+      auto builder = addrRec->addr_info->Build();
+      builder.SortAddresses(NetAddrIPv6FirstComparator());
+      addrRec->addr_info = builder.Finish();
+    }
+
     PrepareRecordExpirationAddrRecord(addrRec);
   }
 
@@ -1673,6 +1695,15 @@ nsHostResolver::LookupStatus nsHostResolver::CompleteLookupByTypeLocked(
   MOZ_ASSERT(rec->pb == pb);
   MOZ_ASSERT(!rec->IsAddrRecord());
 
+  if (rec->LoadNative()) {
+    // If this was resolved using the native resolver
+    // we also need to update the global count.
+    if (rec->LoadUsingAnyThread()) {
+      mActiveAnyThreadCount--;
+      rec->StoreUsingAnyThread(false);
+    }
+  }
+
   RefPtr<TypeHostRecord> typeRec = do_QueryObject(rec);
   MOZ_ASSERT(typeRec);