Revert of Create CSRSS Lockdown feature for finching

content/common/sandbox_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 "content/common/sandbox_win.h"
 
 #include <stddef.h>
 
 #include <string>
 
 #include "base/base_switches.h"
 #include "base/command_line.h"
 #include "base/debug/activity_tracker.h"
 #include "base/debug/profiler.h"
-#include "base/feature_list.h"
 #include "base/files/file_util.h"
 #include "base/hash.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/memory/shared_memory.h"
 #include "base/metrics/field_trial.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/path_service.h"
 #include "base/process/launch.h"
 #include "base/strings/string_number_conversions.h"
@@ skipping 569 matching lines @@
 
 #ifdef _WIN64
   sandbox::ResultCode ret =
       policy->SetJobMemoryLimit(4ULL * 1024 * 1024 * 1024);
   if (ret != sandbox::SBOX_ALL_OK)
     return ret;
 #endif
   return policy->SetJobLevel(job_level, ui_exceptions);
 }
 
-// This is for finch. See also crbug.com/464430 for details.
-const base::Feature kEnableCsrssLockdownFeature{
-    "EnableCsrssLockdown", base::FEATURE_DISABLED_BY_DEFAULT};
-
 // TODO(jschuh): Need get these restrictions applied to NaCl and Pepper.
 // Just have to figure out what needs to be warmed up first.
 sandbox::ResultCode AddBaseHandleClosePolicy(sandbox::TargetPolicy* policy) {
-  if (base::win::GetVersion() >= base::win::VERSION_WIN10) {
-    if (base::FeatureList::IsEnabled(kEnableCsrssLockdownFeature)) {
-      // Close all ALPC ports.
-      sandbox::ResultCode ret =
-          policy->AddKernelObjectToClose(L"ALPC Port", NULL);
-      if (ret != sandbox::SBOX_ALL_OK) {
-        return ret;
-      }
-    }
-  }
   // TODO(cpu): Add back the BaseNamedObjects policy.
   base::string16 object_path = PrependWindowsSessionPath(
       L"\\BaseNamedObjects\\windows_shell_global_counters");
   return policy->AddKernelObjectToClose(L"Section", object_path.data());
 }
 
 sandbox::ResultCode AddAppContainerPolicy(sandbox::TargetPolicy* policy,
                                           const wchar_t* sid) {
   if (IsAppContainerEnabled())
     return policy->SetLowBox(sid);
@@ skipping 244 matching lines @@
   }
 
   delegate->PostSpawnTarget(target.process_handle());
 
   CHECK(ResumeThread(target.thread_handle()) != static_cast<DWORD>(-1));
   *process = base::Process(target.TakeProcessHandle());
   return sandbox::SBOX_ALL_OK;
 }
 
 }  // namespace content