ReadIpHelper: Zero out before calling GetAdaptersAddresses

net/dns/dns_config_service_win.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/dns/dns_config_service_win.h"
 
 #include <algorithm>
 #include <string>
 
 #include "base/bind.h"
@@ skipping 105 matching lines @@
 scoped_ptr<IP_ADAPTER_ADDRESSES, base::FreeDeleter> ReadIpHelper(ULONG flags) {
   base::ThreadRestrictions::AssertIOAllowed();
 
   scoped_ptr<IP_ADAPTER_ADDRESSES, base::FreeDeleter> out;
   ULONG len = 15000;  // As recommended by MSDN for GetAdaptersAddresses.
   UINT rv = ERROR_BUFFER_OVERFLOW;
   // Try up to three times.
   for (unsigned tries = 0; (tries < 3) && (rv == ERROR_BUFFER_OVERFLOW);
        tries++) {
     out.reset(static_cast<PIP_ADAPTER_ADDRESSES>(malloc(len)));
+    memset(out.get(), 0, len);
     rv = GetAdaptersAddresses(AF_UNSPEC, flags, NULL, out.get(), &len);
   }
   if (rv != NO_ERROR)
     out.reset();
   return out.Pass();
 }
 
 // Converts a base::string16 domain name to ASCII, possibly using punycode.
 // Returns true if the conversion succeeds and output is not empty. In case of
 // failure, |domain| might become dirty.
@@ skipping 622 matching lines @@
 }
 
 }  // namespace internal
 
 // static
 scoped_ptr<DnsConfigService> DnsConfigService::CreateSystemService() {
   return scoped_ptr<DnsConfigService>(new internal::DnsConfigServiceWin());
 }
 
 }  // namespace net