permission: clamp Worker grants to parent for explicit execArgv

SEMVER-MAJOR: when the parent has the Permission Model enabled, a Worker
with explicit execArgv (including []) cannot obtain wider permission-related
grants than the parent.

Clamp EnvironmentOptions, rebuild exec_argv_out, and re-parse so
CreateEnvironment and Isolate options stay aligned.

Signed-off-by: yunshingng <yunshingng25@gmail.com>

Author: yunshingng

doc/api/permissions.md

@@ -38,6 +38,15 @@ changes:
     description: This feature is no longer experimental.
 -->
 
+<!-- worker-execargv-permission-ceiling -->
+When the Permission Model is enabled in the parent process, creating a
+`worker_threads.Worker` with an explicit `execArgv` option (including an empty
+array) no longer allows the worker to obtain a wider permission-related grant
+set than the parent. Non-permission `execArgv` flags are unaffected. This is a
+breaking change relative to earlier releases where `execArgv: []` could drop
+the parent's Permission Model grants.
+
+
 > Stability: 2 - Stable
 
 The Node.js Permission Model is a mechanism for restricting access to specific

doc/api/worker_threads.md

@@ -1605,6 +1605,13 @@ changes:
     description: The `resourceLimits` option was introduced.
 -->
 
+<!-- worker-execargv-permission-ceiling -->
+**Permission Model (breaking):** If the parent process runs with the
+Permission Model enabled, an explicit `execArgv` (including `[]`) does not
+disable or exceed the parent's permission-related grants. See the
+[Permission Model](permissions.md#permission-model) documentation.
+
+
 * `filename` {string|URL} The path to the Worker's main script or module. Must
   be either an absolute path or a relative path (i.e. relative to the
   current working directory) starting with `./` or `../`, or a WHATWG `URL`

src/node_worker.cc

@@ -11,6 +11,7 @@
 #include "node_profiling.h"
 #include "node_snapshot_builder.h"
 #include "permission/permission.h"
+#include "path.h"
 #include "util-inl.h"
 #include "v8-cppgc.h"
 #include "v8-profiler.h"
@@ -504,6 +505,173 @@ Worker::~Worker() {
   Debug(this, "Worker %llu destroyed", thread_id_.id);
 }
 
+
+// SEMVER-MAJOR: Permission ceiling for Worker explicit execArgv.
+static bool WorkerConfiguredPermission(const EnvironmentOptions* w) {
+  if (w->permission || w->permission_audit) return true;
+  if (!w->allow_fs_read.empty() || !w->allow_fs_write.empty()) return true;
+  return w->allow_addons || w->allow_inspector || w->allow_child_process ||
+         w->allow_net || w->allow_wasi || w->allow_ffi ||
+         w->allow_openssl_store || w->allow_worker_threads;
+}
+
+static void ApplyParentPermissionCeiling(EnvironmentOptions* w,
+                                         const EnvironmentOptions* parent) {
+  w->permission = true;
+  w->permission_audit = parent->permission_audit;
+  w->allow_addons = parent->allow_addons;
+  w->allow_inspector = parent->allow_inspector;
+  w->allow_child_process = parent->allow_child_process;
+  w->allow_net = parent->allow_net;
+  w->allow_wasi = parent->allow_wasi;
+  w->allow_ffi = parent->allow_ffi;
+  w->allow_openssl_store = parent->allow_openssl_store;
+  w->allow_worker_threads = parent->allow_worker_threads;
+  w->allow_fs_read = parent->allow_fs_read;
+  w->allow_fs_write = parent->allow_fs_write;
+}
+
+static void NormalizePathForCompare(std::string* s) {
+  while (s->size() > 1 && (s->back() == '/' || s->back() == '\\')) {
+    s->pop_back();
+  }
+#ifdef _WIN32
+  for (char& c : *s) {
+    if (c >= 'A' && c <= 'Z') c = static_cast<char>(c - 'A' + 'a');
+    if (c == '/') c = '\\';
+  }
+#endif
+}
+
+static std::string ResolveForCompare(Environment* env, const std::string& in) {
+  if (in.empty() || in == "*") return in;
+  std::string resolved =
+      PathResolve(env, std::vector<std::string_view>{std::string_view(in)});
+  if (resolved.empty()) resolved = in;
+  NormalizePathForCompare(&resolved);
+  return resolved;
+}
+
+static bool PathCoveredByParentEntry(Environment* env,
+                                     const std::string& parent_raw,
+                                     const std::string& requested_raw) {
+  if (parent_raw == "*") return true;
+  const std::string parent = ResolveForCompare(env, parent_raw);
+  const std::string requested = ResolveForCompare(env, requested_raw);
+  if (parent.empty()) return false;
+  if (requested == parent) return true;
+  if (requested.size() <= parent.size()) return false;
+  if (requested.compare(0, parent.size(), parent) != 0) return false;
+  const char next = requested[parent.size()];
+  return next == '/' || next == '\\';
+}
+
+static bool ParentListHasWildcard(const std::vector<std::string>& parent) {
+  for (const std::string& p : parent) {
+    if (p == "*") return true;
+  }
+  return false;
+}
+
+static void FilterPathListToParentSubset(
+    Environment* env,
+    EnvironmentOptions* w,
+    std::vector<std::string>* worker,
+    const std::vector<std::string>& parent) {
+  if (worker == nullptr) return;
+  if (worker->empty()) {
+    if (w->permission || w->permission_audit) return;
+    *worker = parent;
+    return;
+  }
+  if (ParentListHasWildcard(parent)) return;
+  std::vector<std::string> out;
+  out.reserve(worker->size());
+  for (const std::string& wpath : *worker) {
+    if (wpath == "*") continue;
+    for (const std::string& p : parent) {
+      if (PathCoveredByParentEntry(env, p, wpath)) {
+        out.push_back(wpath);
+        break;
+      }
+    }
+  }
+  *worker = std::move(out);
+}
+
+static void IntersectPermissionGrants(Environment* env,
+                                      EnvironmentOptions* w,
+                                      const EnvironmentOptions* parent) {
+  w->permission = true;
+  w->permission_audit = w->permission_audit || parent->permission_audit;
+  w->allow_addons = w->allow_addons && parent->allow_addons;
+  w->allow_inspector = w->allow_inspector && parent->allow_inspector;
+  w->allow_child_process =
+      w->allow_child_process && parent->allow_child_process;
+  w->allow_net = w->allow_net && parent->allow_net;
+  w->allow_wasi = w->allow_wasi && parent->allow_wasi;
+  w->allow_ffi = w->allow_ffi && parent->allow_ffi;
+  w->allow_openssl_store =
+      w->allow_openssl_store && parent->allow_openssl_store;
+  w->allow_worker_threads =
+      w->allow_worker_threads && parent->allow_worker_threads;
+  FilterPathListToParentSubset(env, w, &w->allow_fs_read, parent->allow_fs_read);
+  FilterPathListToParentSubset(
+      env, w, &w->allow_fs_write, parent->allow_fs_write);
+}
+
+static void ClampWorkerPermissionToParent(Environment* env,
+                                          PerIsolateOptions* worker_opts) {
+  if (worker_opts == nullptr || !env->permission()->enabled()) return;
+  EnvironmentOptions* parent = env->isolate_data()->options()->get_per_env_options();
+  EnvironmentOptions* w = worker_opts->get_per_env_options();
+  if (parent == nullptr || w == nullptr) return;
+  if (!WorkerConfiguredPermission(w)) {
+    ApplyParentPermissionCeiling(w, parent);
+  } else {
+    IntersectPermissionGrants(env, w, parent);
+  }
+}
+
+static void RebuildExecArgvOutFromPermissionOptions(
+    PerIsolateOptions* worker_opts, std::vector<std::string>* exec_argv_out) {
+  if (worker_opts == nullptr || exec_argv_out == nullptr) return;
+  EnvironmentOptions* w = worker_opts->get_per_env_options();
+  if (w == nullptr || !w->permission) return;
+
+  std::vector<std::string> out;
+  out.emplace_back("");
+  auto is_perm = [](const std::string& a) {
+    return a == "--permission" || a == "--permission-audit" ||
+           a.rfind("--allow-fs-read", 0) == 0 ||
+           a.rfind("--allow-fs-write", 0) == 0 || a == "--allow-addons" ||
+           a == "--allow-inspector" || a == "--allow-child-process" ||
+           a == "--allow-net" || a == "--allow-wasi" || a == "--allow-ffi" ||
+           a == "--allow-openssl-store" || a == "--allow-worker";
+  };
+  for (size_t i = 1; i < exec_argv_out->size(); i++) {
+    if (!is_perm((*exec_argv_out)[i])) out.push_back((*exec_argv_out)[i]);
+  }
+  out.push_back("--permission");
+  if (w->permission_audit) out.push_back("--permission-audit");
+  if (w->allow_addons) out.push_back("--allow-addons");
+  if (w->allow_inspector) out.push_back("--allow-inspector");
+  if (w->allow_child_process) out.push_back("--allow-child-process");
+  if (w->allow_net) out.push_back("--allow-net");
+  if (w->allow_wasi) out.push_back("--allow-wasi");
+  if (w->allow_ffi) out.push_back("--allow-ffi");
+  if (w->allow_openssl_store) out.push_back("--allow-openssl-store");
+  if (w->allow_worker_threads) out.push_back("--allow-worker");
+  for (const std::string& path : w->allow_fs_read) {
+    out.push_back("--allow-fs-read=" + path);
+  }
+  for (const std::string& path : w->allow_fs_write) {
+    out.push_back("--allow-fs-write=" + path);
+  }
+  *exec_argv_out = std::move(out);
+}
+
+
 void Worker::New(const FunctionCallbackInfo<Value>& args) {
   Environment* env = Environment::GetCurrent(args);
   THROW_IF_INSUFFICIENT_PERMISSIONS(
@@ -683,6 +851,27 @@ void Worker::New(const FunctionCallbackInfo<Value>& args) {
     per_isolate_opts = env->isolate_data()->options()->Clone();
   }
 
+  if (env->permission()->enabled() && per_isolate_opts) {
+    ClampWorkerPermissionToParent(env, per_isolate_opts.get());
+    if (args[2]->IsArray()) {
+      RebuildExecArgvOutFromPermissionOptions(per_isolate_opts.get(),
+                                              &exec_argv_out);
+      // Re-parse so per_isolate_opts stay aligned with exec_argv_out.
+      std::vector<std::string> exec_argv_copy = exec_argv_out;
+      std::vector<std::string> ignored_out;
+      std::vector<std::string> invalid_args2;
+      std::vector<std::string> errors2;
+      options_parser::Parse(&exec_argv_copy,
+                            &ignored_out,
+                            &invalid_args2,
+                            per_isolate_opts.get(),
+                            kDisallowedInEnvvar,
+                            &errors2);
+      // Keep the rebuilt argv as the one passed to CreateEnvironment.
+      // Parse consumes/moves copy; exec_argv_out already holds final tokens.
+    }
+  }
+
   // Internal workers should not wait for inspector frontend to connect or
   // break on the first line of internal scripts. Module loader threads are
   // essential to load user codes and must not be blocked by the inspector

test/parallel/test-permission-worker-empty-execargv.js

@@ -0,0 +1,129 @@
+'use strict';
+const common = require('../common');
+const { isMainThread } = require('worker_threads');
+if (!isMainThread) common.skip('This test only works on a main thread');
+if (!common.hasCrypto) common.skip('no crypto');
+const assert = require('assert');
+const fs = require('fs');
+const path = require('path');
+const { spawnSync } = require('child_process');
+const tmpdir = require('../common/tmpdir');
+tmpdir.refresh();
+const allowedDir = tmpdir.path;
+const allowedFile = path.join(allowedDir, 'ok.txt');
+const subFile = path.join(allowedDir, 'sub', 'nested.txt');
+fs.mkdirSync(path.dirname(subFile), { recursive: true });
+const deniedDir = fs.mkdtempSync(path.join(path.dirname(tmpdir.path), 'perm-deny-'));
+const deniedFile = path.join(deniedDir, 'secret.txt');
+fs.writeFileSync(allowedFile, 'allowed\n');
+fs.writeFileSync(subFile, 'nested\n');
+fs.writeFileSync(deniedFile, 'secret\n');
+function runWorkerCase(workerBody, execArgvFragment) {
+  const code = `
+    const { Worker } = require('worker_threads');
+    const w = new Worker(${JSON.stringify(workerBody)}, {
+      eval: true,
+      ${execArgvFragment}
+    });
+    w.on('message', (msg) => {
+      process.stdout.write(JSON.stringify(msg) + '\\n');
+      process.exit(0);
+    });
+    w.on('error', (err) => { console.error(err); process.exit(1); });
+  `;
+  return spawnSync(
+    process.execPath,
+    ['--permission', `--allow-fs-read=${allowedDir}`, '--allow-worker', '-e', code],
+    { encoding: 'utf8', timeout: 30000, env: { ...process.env } },
+  );
+}
+function parseLastJsonLine(stdout) {
+  const lines = stdout.trim().split('\n').filter(Boolean);
+  assert.ok(lines.length > 0, 'expected worker JSON output');
+  return JSON.parse(lines[lines.length - 1]);
+}
+function workerRead(filePath) {
+  return `
+    const { parentPort } = require('worker_threads');
+    const fs = require('fs');
+    try {
+      parentPort.postMessage({
+        ok: true,
+        data: fs.readFileSync(${JSON.stringify(filePath)}, 'utf8'),
+      });
+    } catch (err) {
+      parentPort.postMessage({ ok: false, code: err.code });
+    }
+  `;
+}
+function assertAccessDenied(msg) {
+  assert.strictEqual(msg.ok, false, JSON.stringify(msg));
+  assert.strictEqual(msg.code, 'ERR_ACCESS_DENIED');
+}
+function assertOk(msg) {
+  assert.strictEqual(msg.ok, true, JSON.stringify(msg));
+}
+try {
+  {
+    const r = runWorkerCase(workerRead(deniedFile), '');
+    assert.strictEqual(r.status, 0, r.stderr);
+    assertAccessDenied(parseLastJsonLine(r.stdout));
+  }
+  {
+    const denied = runWorkerCase(workerRead(deniedFile), 'execArgv: [],');
+    assert.strictEqual(denied.status, 0, denied.stderr);
+    assertAccessDenied(parseLastJsonLine(denied.stdout));
+    const allowed = runWorkerCase(workerRead(allowedFile), 'execArgv: [],');
+    assert.strictEqual(allowed.status, 0, allowed.stderr);
+    assertOk(parseLastJsonLine(allowed.stdout));
+    const nested = runWorkerCase(workerRead(subFile), 'execArgv: [],');
+    assert.strictEqual(nested.status, 0, nested.stderr);
+    assertOk(parseLastJsonLine(nested.stdout));
+  }
+  {
+    const denied = runWorkerCase(workerRead(deniedFile), 'execArgv: ["--no-warnings"],');
+    assert.strictEqual(denied.status, 0, denied.stderr);
+    assertAccessDenied(parseLastJsonLine(denied.stdout));
+    const allowed = runWorkerCase(workerRead(allowedFile), 'execArgv: ["--no-warnings"],');
+    assert.strictEqual(allowed.status, 0, allowed.stderr);
+    assertOk(parseLastJsonLine(allowed.stdout));
+  }
+  {
+    const frag = `execArgv: ${JSON.stringify(['--permission', '--allow-worker'])},`;
+    const d = runWorkerCase(workerRead(deniedFile), frag);
+    assert.strictEqual(d.status, 0, d.stderr);
+    assertAccessDenied(parseLastJsonLine(d.stdout));
+    const a = runWorkerCase(workerRead(allowedFile), frag);
+    assert.strictEqual(a.status, 0, a.stderr);
+    assertAccessDenied(parseLastJsonLine(a.stdout));
+  }
+  {
+    const frag = `execArgv: ${JSON.stringify(['--permission', '--allow-fs-read=*', '--allow-worker'])},`;
+    const r = runWorkerCase(workerRead(deniedFile), frag);
+    assert.strictEqual(r.status, 0, r.stderr);
+    assertAccessDenied(parseLastJsonLine(r.stdout));
+  }
+  {
+    const frag = `execArgv: ${JSON.stringify([
+      '--permission',
+      `--allow-fs-read=${allowedDir}`,
+      `--allow-fs-read=${deniedFile}`,
+      '--allow-worker',
+    ])},`;
+    const r = runWorkerCase(workerRead(deniedFile), frag);
+    assert.strictEqual(r.status, 0, r.stderr);
+    assertAccessDenied(parseLastJsonLine(r.stdout));
+  }
+  {
+    const frag = `execArgv: ${JSON.stringify([
+      '--permission',
+      `--allow-fs-read=${subFile}`,
+      '--allow-worker',
+    ])},`;
+    const r = runWorkerCase(workerRead(subFile), frag);
+    assert.strictEqual(r.status, 0, r.stderr);
+    assertOk(parseLastJsonLine(r.stdout));
+  }
+} finally {
+  fs.rmSync(deniedDir, { recursive: true, force: true });
+}