Give plug-in processes an executable heap and disable PIE/ASLR for Native

chrome/browser/nacl_host/nacl_process_host.cc

 // Copyright (c) 2011 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 "build/build_config.h"
 
 #include "chrome/browser/nacl_host/nacl_process_host.h"
 
 #if defined(OS_POSIX)
 #include <fcntl.h>
@@ skipping 127 matching lines @@
   if (!CreateChannel())
     return false;
 
   CommandLine::StringType nacl_loader_prefix;
 #if defined(OS_POSIX)
   nacl_loader_prefix = CommandLine::ForCurrentProcess()->GetSwitchValueNative(
       switches::kNaClLoaderCmdPrefix);
 #endif  // defined(OS_POSIX)
 
   // Build command line for nacl.
-  FilePath exe_path = GetChildPath(nacl_loader_prefix.empty());
+
+#if defined(OS_MACOSX)
+  // The Native Client process needs to be able to allocate a 1GB contiguous
+  // region to use as the client environment's virtual address space. ASLR
+  // (PIE) interferes with this by making it possible that no gap large enough
+  // to accomodate this request will exist in the child process' address
+  // space. Disable PIE for NaCl processes. See http://crbug.com/90221 and
+  // http://code.google.com/p/nativeclient/issues/detail?id=2043.
+  int flags = CHILD_NO_PIE;
+#elif defined(OS_LINUX)
+  int flags = nacl_loader_prefix.empty() ? CHILD_ALLOW_SELF : CHILD_NORMAL;
+#else
+  int flags = CHILD_NORMAL;
+#endif
+
+  FilePath exe_path = GetChildPath(flags);
   if (exe_path.empty())
     return false;
 
   CommandLine* cmd_line = new CommandLine(exe_path);
   nacl::CopyNaClCommandLineArguments(cmd_line);
 
   cmd_line->AppendSwitchASCII(switches::kProcessType,
                               switches::kNaClLoaderProcess);
 
   cmd_line->AppendSwitchASCII(switches::kProcessChannelID, channel_id());
@@ skipping 209 matching lines @@
 }
 
 bool NaClProcessHost::OnMessageReceived(const IPC::Message& msg) {
   NOTREACHED() << "Invalid message with type = " << msg.type();
   return false;
 }
 
 bool NaClProcessHost::CanShutdown() {
   return true;
 }