electron/patches/chromium/support_mixed_sandbox_with_zygote.patch
2021-03-04 15:46:13 -08:00

84 lines
3.5 KiB
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From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Jeremy Apthorp <nornagon@nornagon.net>
Date: Wed, 28 Nov 2018 13:20:27 -0800
Subject: support_mixed_sandbox_with_zygote.patch
On Linux, Chromium launches all new renderer processes via a "zygote"
process which has the sandbox pre-initialized (see
//docs/linux_zygote.md). In order to support mixed-sandbox mode, in
which some renderers are launched with the sandbox engaged and others
without it, we need the option to launch non-sandboxed renderers without
going through the zygote.
Chromium already supports a `--no-zygote` flag, but it turns off the
zygote completely, and thus also disables sandboxing. This patch allows
the `--no-zygote` flag to affect renderer processes on a case-by-case
basis, checking immediately prior to launch whether to go through the
zygote or not based on the command-line of the to-be-launched renderer.
This patch could conceivably be upstreamed, as it does not affect
production Chromium (which does not use the `--no-zygote` flag).
However, the patch would need to be reviewed by the security team, as it
does touch a security-sensitive class.
diff --git a/content/browser/renderer_host/render_process_host_impl.cc b/content/browser/renderer_host/render_process_host_impl.cc
index 5e67fd252d6ce17d8093b81d89dec32756a8ba3b..1b93f610a23c1e1c1ec5a90bfcc9958ec06aad65 100644
--- a/content/browser/renderer_host/render_process_host_impl.cc
+++ b/content/browser/renderer_host/render_process_host_impl.cc
@@ -400,6 +400,11 @@ class RendererSandboxedProcessLauncherDelegate
{
}
+#if BUILDFLAG(USE_ZYGOTE_HANDLE)
+ RendererSandboxedProcessLauncherDelegate(bool use_zygote):
+ use_zygote_(use_zygote) {}
+#endif
+
~RendererSandboxedProcessLauncherDelegate() override = default;
#if defined(OS_WIN)
@@ -428,6 +433,9 @@ class RendererSandboxedProcessLauncherDelegate
#if BUILDFLAG(USE_ZYGOTE_HANDLE)
ZygoteHandle GetZygote() override {
+ if (!use_zygote_) {
+ return nullptr;
+ }
const base::CommandLine& browser_command_line =
*base::CommandLine::ForCurrentProcess();
base::CommandLine::StringType renderer_prefix =
@@ -446,10 +454,13 @@ class RendererSandboxedProcessLauncherDelegate
return sandbox::policy::SandboxType::kRenderer;
}
-#if defined(OS_WIN)
private:
+#if defined(OS_WIN)
const bool renderer_code_integrity_enabled_;
#endif
+#if BUILDFLAG(USE_ZYGOTE_HANDLE)
+ bool use_zygote_ = true;
+#endif
};
const char kSessionStorageHolderKey[] = "kSessionStorageHolderKey";
@@ -1908,11 +1919,18 @@ bool RenderProcessHostImpl::Init() {
cmd_line->PrependWrapper(renderer_prefix);
AppendRendererCommandLine(cmd_line.get());
+#if BUILDFLAG(USE_ZYGOTE_HANDLE)
+ bool use_zygote = !cmd_line->HasSwitch(switches::kNoZygote);
+ auto delegate = std::make_unique<RendererSandboxedProcessLauncherDelegate>(use_zygote);
+#else
+ auto delegate = std::make_unique<RendererSandboxedProcessLauncherDelegate>();
+#endif
+
// Spawn the child process asynchronously to avoid blocking the UI thread.
// As long as there's no renderer prefix, we can use the zygote process
// at this stage.
child_process_launcher_ = std::make_unique<ChildProcessLauncher>(
- std::make_unique<RendererSandboxedProcessLauncherDelegate>(),
+ std::move(delegate),
std::move(cmd_line), GetID(), this, std::move(mojo_invitation_),
base::BindRepeating(&RenderProcessHostImpl::OnMojoError, id_),
GetV8SnapshotFilesToPreload());