From 9c9aefe2a09d601a36366062c856f852f3778b00 Mon Sep 17 00:00:00 2001
From: Anna Henningsen <anna@addaleax.net>
Date: Tue, 5 Feb 2019 21:51:28 +0100
Subject: [PATCH] worker: set stack size for worker threads
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This is so we can inform V8 about a known limit for the stack.

Otherwise, on some systems recursive functions may lead to
segmentation faults rather than “safe” failures.

PR-URL: https://github.com/nodejs/node/pull/26049
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
---
 src/node_worker.cc                          | 13 ++++++++++++-
 src/node_worker.h                           |  6 ++++++
 test/parallel/test-worker-stack-overflow.js | 11 +++++++++++
 3 files changed, 29 insertions(+), 1 deletion(-)
 create mode 100644 test/parallel/test-worker-stack-overflow.js

diff --git a/src/node_worker.cc b/src/node_worker.cc
index ebd1924b8f2479..f38b187c18c5b8 100644
--- a/src/node_worker.cc
+++ b/src/node_worker.cc
@@ -118,6 +118,8 @@ class WorkerThreadData {
     {
       Locker locker(isolate);
       Isolate::Scope isolate_scope(isolate);
+      isolate->SetStackLimit(w_->stack_base_);
+
       HandleScope handle_scope(isolate);
       isolate_data_.reset(CreateIsolateData(isolate,
                                             &loop_,
@@ -488,8 +490,17 @@ void Worker::StartThread(const FunctionCallbackInfo<Value>& args) {
     static_cast<Worker*>(handle->data)->OnThreadStopped();
   }), 0);
 
-  CHECK_EQ(uv_thread_create(&w->tid_, [](void* arg) {
+  uv_thread_options_t thread_options;
+  thread_options.flags = UV_THREAD_HAS_STACK_SIZE;
+  thread_options.stack_size = kStackSize;
+  CHECK_EQ(uv_thread_create_ex(&w->tid_, &thread_options, [](void* arg) {
     Worker* w = static_cast<Worker*>(arg);
+    const uintptr_t stack_top = reinterpret_cast<uintptr_t>(&arg);
+
+    // Leave a few kilobytes just to make sure we're within limits and have
+    // some space to do work in C++ land.
+    w->stack_base_ = stack_top - (kStackSize - kStackBufferSize);
+
     w->Run();
 
     Mutex::ScopedLock lock(w->mutex_);
diff --git a/src/node_worker.h b/src/node_worker.h
index 4d7a7335ca6d63..68848c859990f0 100644
--- a/src/node_worker.h
+++ b/src/node_worker.h
@@ -80,6 +80,12 @@ class Worker : public AsyncWrap {
   bool thread_joined_ = true;
   int exit_code_ = 0;
   uint64_t thread_id_ = -1;
+  uintptr_t stack_base_;
+
+  // Full size of the thread's stack.
+  static constexpr size_t kStackSize = 4 * 1024 * 1024;
+  // Stack buffer size that is not available to the JS engine.
+  static constexpr size_t kStackBufferSize = 192 * 1024;
 
   std::unique_ptr<MessagePortData> child_port_data_;
 
diff --git a/test/parallel/test-worker-stack-overflow.js b/test/parallel/test-worker-stack-overflow.js
new file mode 100644
index 00000000000000..99a34b5369006f
--- /dev/null
+++ b/test/parallel/test-worker-stack-overflow.js
@@ -0,0 +1,11 @@
+'use strict';
+const common = require('../common');
+const assert = require('assert');
+const { Worker } = require('worker_threads');
+
+const worker = new Worker('function f() { f(); } f();', { eval: true });
+
+worker.on('error', common.mustCall((err) => {
+  assert.strictEqual(err.constructor, RangeError);
+  assert.strictEqual(err.message, 'Maximum call stack size exceeded');
+}));