Revert 98909 - Use chain-loading for Linux nacl_helper

chrome/nacl/nacl_fork_delegate_linux.cc

Index: chrome/nacl/nacl_fork_delegate_linux.cc
===================================================================
--- chrome/nacl/nacl_fork_delegate_linux.cc	(revision 98909)
+++ chrome/nacl/nacl_fork_delegate_linux.cc	(working copy)
@@ -26,8 +26,6 @@
       sandboxed_(false),
       fd_(-1) {}
 
-const char kNaClHelperAtZero[] = "--at-zero";
-
 void NaClForkDelegate::Init(const bool sandboxed,
                             const int browserdesc,
                             const int sandboxdesc) {
@@ -50,18 +48,18 @@
   const bool use_helper = CommandLine::ForCurrentProcess()->HasSwitch(
       switches::kNaClLinuxHelper);
   FilePath helper_exe;
-  FilePath helper_bootstrap_exe;
-  if (use_helper &&
-      PathService::Get(chrome::FILE_NACL_HELPER, &helper_exe) &&
-      PathService::Get(chrome::FILE_NACL_HELPER_BOOTSTRAP,
-                       &helper_bootstrap_exe)) {
+  if (use_helper && PathService::Get(chrome::FILE_NACL_HELPER, &helper_exe)) {
     CommandLine::StringVector argv = CommandLine::ForCurrentProcess()->argv();
-    argv[0] = helper_bootstrap_exe.value();
-    argv[1] = helper_exe.value();
-    argv[2] = kNaClHelperAtZero;
+    argv[0] = helper_exe.value();
     base::LaunchOptions options;
     options.fds_to_remap = &fds_to_map;
     options.clone_flags = CLONE_FS | SIGCHLD;
+    // LD_BIND_NOW forces non-lazy binding in the dynamic linker, to
+    // prevent the linker from trying to look at the text of the nacl_helper
+    // program after it has been replaced by the nacl module.
+    base::environment_vector env;
+    env.push_back(std::make_pair("LD_BIND_NOW", "1"));
+    options.environ = &env;
     ready_ = base::LaunchProcess(argv, options, NULL);
     // parent and error cases are handled below
   }