Non-SFI mode: Use dummy PID for NaCl's IPC channel on Linux platform.

components/nacl/loader/nacl_helper_linux.cc

Index: components/nacl/loader/nacl_helper_linux.cc
diff --git a/components/nacl/loader/nacl_helper_linux.cc b/components/nacl/loader/nacl_helper_linux.cc
index d5b9fdf227ffccf7d095097b7182b131f265f355..8008e6b6f3e341bdf56f2ed01450fdc0cffa643e 100644
--- a/components/nacl/loader/nacl_helper_linux.cc
+++ b/components/nacl/loader/nacl_helper_linux.cc
@@ -48,6 +48,7 @@
 #include "content/public/common/content_descriptors.h"
 #include "content/public/common/zygote_fork_delegate_linux.h"
 #include "crypto/nss_util.h"
+#include "ipc/ipc_channel.h"
 #include "ipc/ipc_descriptors.h"
 #include "ipc/ipc_switches.h"
 #include "sandbox/linux/services/libc_urandom_override.h"
@@ -407,6 +408,7 @@ int main(int argc, char* argv[]) {
   // Now do nothing in main for nacl_helper_nonsfi.

[Mark Seaborn, 2014/12/03 01:54:00]

Can you rebase this change, so that I can see what the current context is?

[hidehiko, 2014/12/03 17:03:19]

Done.

 #if !defined(__native_client_nonsfi__)
   CommandLine::Init(argc, argv);
+  IPC::Channel::SetGlobalPid(-1);  // Set dummy PID for IPC.

[mdempsky, 2014/11/07 03:05:34]

Is this the right place to put this call?  It looks like this for !nonsfi,
whereas in ipc_channel.h it seems like SetGlobalPid() is only available for
OS_LINUX and NONSFI.  I would think this wouldn't compile under SFI.

[hidehiko, 2014/11/07 05:43:21]

Yes, this is the right place.
This is not only for nonsfi but also for sfi. Note that nacl_helper for sfi mode
is build by host toolchain (i.e. under OS_LINUX rather than OS_NACL). We won't
compile this file to SFI nexe binary.

   base::AtExitManager exit_manager;
   base::RandUint64();  // acquire /dev/urandom fd before sandbox is raised
   // Allows NSS to fopen() /dev/urandom.