Ensure that the DirectWrite font cache works in Chrome canary on Windows 8+ with AppContainer prote…

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 <string>
 
 #include "base/base_switches.h"
 #include "base/command_line.h"
 #include "base/debug/profiler.h"
 #include "base/files/file_util.h"
 #include "base/hash.h"
+#include "base/memory/shared_memory.h"
 #include "base/metrics/sparse_histogram.h"
 #include "base/path_service.h"
 #include "base/process/launch.h"
+#include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/trace_event/trace_event.h"
 #include "base/win/iat_patch_function.h"
 #include "base/win/scoped_handle.h"
 #include "base/win/scoped_process_information.h"
 #include "base/win/windows_version.h"
 #include "content/common/content_switches_internal.h"
 #include "content/public/common/content_client.h"
 #include "content/public/common/content_switches.h"
+#include "content/public/common/dwrite_font_platform_win.h"
 #include "content/public/common/sandbox_init.h"
 #include "content/public/common/sandboxed_process_launcher_delegate.h"
 #include "sandbox/win/src/process_mitigations.h"
 #include "sandbox/win/src/sandbox.h"
 #include "sandbox/win/src/sandbox_nt_util.h"
 #include "sandbox/win/src/sandbox_policy_base.h"
 #include "sandbox/win/src/win_utils.h"
 #include "ui/gfx/win/direct_write.h"
 
 static sandbox::BrokerServices* g_broker_services = NULL;
@@ skipping 633 matching lines @@
     return base::Process();
 
   if (type_str == switches::kRendererProcess) {
 #if !defined(NACL_WIN64)
     if (gfx::win::ShouldUseDirectWrite()) {
       AddDirectory(base::DIR_WINDOWS_FONTS,
                   NULL,
                   true,
                   sandbox::TargetPolicy::FILES_ALLOW_READONLY,
                   policy);
+
+      // If DirectWrite is enabled for font rendering then open the font cache
+      // section which is created by the browser and pass the handle to the
+      // renderer process. This is needed because renderer processes on
+      // Windows 8+ may be running in an AppContainer sandbox and hence their
+      // kernel object namespace may be partitioned.
+      std::string name(content::kFontCacheSharedSectionName);
+      name.append(base::UintToString(base::GetCurrentProcId()));
+
+      base::SharedMemory direct_write_font_cache_section;
+      if (direct_write_font_cache_section.Open(name, true)) {
+        void* shared_handle =
+            policy->AddHandleToShare(direct_write_font_cache_section.handle());
+        cmd_line->AppendSwitchASCII(switches::kFontCacheSharedHandle,
+            base::UintToString(reinterpret_cast<unsigned int>(shared_handle)));
+      }
     }
 #endif
   } else {
     // Hack for Google Desktop crash. Trick GD into not injecting its DLL into
     // this subprocess. See
     // http://code.google.com/p/chromium/issues/detail?id=25580
     cmd_line->AppendSwitchASCII("ignored", " --type=renderer ");
   }
 
   sandbox::ResultCode result;
@@ skipping 103 matching lines @@
   }
 
   return false;
 }
 
 bool BrokerAddTargetPeer(HANDLE peer_process) {
   return g_broker_services->AddTargetPeer(peer_process) == sandbox::SBOX_ALL_OK;
 }
 
 }  // namespace content