[Linux] Use PR_SET_NO_NEW_PRIVS by default in base/process/launch.h.

base/test/launcher/test_launcher.cc

 // Copyright 2013 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 "base/test/launcher/test_launcher.h"
 
 #if defined(OS_POSIX)
 #include <fcntl.h>
 #endif
 
@@ skipping 1008 matching lines @@
   if (!SetJobObjectLimitFlags(job_handle.Get(),
                               JOB_OBJECT_LIMIT_KILL_ON_JOB_CLOSE |
                               JOB_OBJECT_LIMIT_BREAKAWAY_OK)) {
     LOG(ERROR) << "Could not SetJobObjectLimitFlags.";
     return -1;
   }
 
   new_options.job_handle = job_handle.Get();
 #endif  // defined(OS_WIN)
 
+#if defined(OS_LINUX)
+  // To prevent accidental privilege sharing to an untrusted child, processes
+  // are started with PR_SET_NO_NEW_PRIVS. Do not set that here, since this
+  // new child will be privileged and trusted.
+  new_options.allow_new_privs = true;
+#endif
+
   base::ProcessHandle process_handle;
 
   {
     // Note how we grab the lock before the process possibly gets created.
     // This ensures that when the lock is held, ALL the processes are registered
     // in the set.
     AutoLock lock(g_live_processes_lock.Get());
 
     if (!base::LaunchProcess(command_line, new_options, &process_handle))
       return -1;
@@ skipping 30 matching lines @@
 
     g_live_processes.Get().erase(process_handle);
   }
 
   base::CloseProcessHandle(process_handle);
 
   return exit_code;
 }
 
 }  // namespace base