From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Jeremy Apthorp <nornagon@nornagon.net>
Date: Mon, 26 Aug 2019 12:02:51 -0700
Subject: allow new privileges in unsandboxed child processes

This allows unsandboxed renderers to launch setuid processes on Linux.

diff --git a/content/browser/child_process_launcher_helper_linux.cc b/content/browser/child_process_launcher_helper_linux.cc
index 16d838b710d4f717733f4aa8f92f144922969b3b..ff2c78c7b803159dde97dafdb799d9b8761dc3fd 100644
--- a/content/browser/child_process_launcher_helper_linux.cc
+++ b/content/browser/child_process_launcher_helper_linux.cc
@@ -54,6 +54,18 @@ bool ChildProcessLauncherHelper::BeforeLaunchOnLauncherThread(
   if (GetProcessType() == switches::kRendererProcess) {
     const int sandbox_fd = SandboxHostLinux::GetInstance()->GetChildSocket();
     options->fds_to_remap.push_back(std::make_pair(sandbox_fd, GetSandboxFD()));
+
+    // (For Electron), if we're launching without zygote, that means we're
+    // launching an unsandboxed process (since all sandboxed processes are
+    // forked from the zygote). Relax the allow_new_privs option to permit
+    // launching suid processes from unsandboxed renderers.
+    ZygoteHandle zygote_handle =
+        base::CommandLine::ForCurrentProcess()->HasSwitch(switches::kNoZygote)
+            ? nullptr
+            : delegate_->GetZygote();
+    if (!zygote_handle) {
+      options->allow_new_privs = true;
+    }
   }
 
   for (const auto& remapped_fd : file_data_->additional_remapped_fds) {
