Adding upstream version 115.8.0esr.upstream/115.8.0esr

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 536 insertions, 0 deletions

diff --git a/browser/app/winlauncher/LauncherProcessWin.cpp b/browser/app/winlauncher/LauncherProcessWin.cpp
new file mode 100644
index 0000000000..082ada9ea7
--- /dev/null
+++ b/browser/app/winlauncher/LauncherProcessWin.cpp
@@ -0,0 +1,536 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+#include "LauncherProcessWin.h"
+
+#include <string.h>
+
+#include "mozilla/Attributes.h"
+#include "mozilla/CmdLineAndEnvUtils.h"
+#include "mozilla/DebugOnly.h"
+#include "mozilla/DynamicallyLinkedFunctionPtr.h"
+#include "mozilla/glue/Debug.h"
+#include "mozilla/GeckoArgs.h"
+#include "mozilla/Maybe.h"
+#include "mozilla/SafeMode.h"
+#include "mozilla/UniquePtr.h"
+#include "mozilla/WindowsConsole.h"
+#include "mozilla/WindowsVersion.h"
+#include "mozilla/WinHeaderOnlyUtils.h"
+#include "nsWindowsHelpers.h"
+
+#include <windows.h>
+#include <processthreadsapi.h>
+
+#include "DllBlocklistInit.h"
+#include "ErrorHandler.h"
+#include "LaunchUnelevated.h"
+#include "ProcThreadAttributes.h"
+#include "../BrowserDefines.h"
+
+#if defined(MOZ_LAUNCHER_PROCESS)
+#  include "mozilla/LauncherRegistryInfo.h"
+#  include "SameBinary.h"
+#endif  // defined(MOZ_LAUNCHER_PROCESS)
+
+#if defined(MOZ_SANDBOX)
+#  include "mozilla/sandboxing/SandboxInitialization.h"
+#endif
+
+namespace mozilla {
+// "const" because nothing in this process modifies it.
+// "volatile" because something in another process may.
+const volatile DeelevationStatus gDeelevationStatus =
+    DeelevationStatus::DefaultStaticValue;
+}  // namespace mozilla
+
+/**
+ * At this point the child process has been created in a suspended state. Any
+ * additional startup work (eg, blocklist setup) should go here.
+ *
+ * @return Ok if browser startup should proceed
+ */
+static mozilla::LauncherVoidResult PostCreationSetup(
+    const wchar_t* aFullImagePath, HANDLE aChildProcess,
+    HANDLE aChildMainThread, mozilla::DeelevationStatus aDStatus,
+    const bool aIsSafeMode, const bool aDisableDynamicBlocklist,
+    mozilla::Maybe<std::wstring> aBlocklistFileName) {
+  /* scope for txManager */ {
+    mozilla::nt::CrossExecTransferManager txManager(aChildProcess);
+    if (!txManager) {
+      return LAUNCHER_ERROR_FROM_WIN32(ERROR_BAD_EXE_FORMAT);
+    }
+
+    using mozilla::gDeelevationStatus;
+
+    void* targetAddress = (LPVOID)&gDeelevationStatus;
+
+    auto const guard = txManager.Protect(
+        targetAddress, sizeof(gDeelevationStatus), PAGE_READWRITE);
+
+    mozilla::LauncherVoidResult result =
+        txManager.Transfer(targetAddress, &aDStatus, sizeof(aDStatus));
+    if (result.isErr()) {
+      return result;
+    }
+  }
+
+  return mozilla::InitializeDllBlocklistOOPFromLauncher(
+      aFullImagePath, aChildProcess, aDisableDynamicBlocklist,
+      aBlocklistFileName);
+}
+
+/**
+ * Create a new Job object and assign |aProcess| to it.  If something fails
+ * in this function, we return nullptr but continue without recording
+ * a launcher failure because it's not a critical problem to launch
+ * the browser process.
+ */
+static nsReturnRef<HANDLE> CreateJobAndAssignProcess(HANDLE aProcess) {
+  nsAutoHandle empty;
+  nsAutoHandle job(::CreateJobObjectW(nullptr, nullptr));
+
+  // Set JOB_OBJECT_LIMIT_BREAKAWAY_OK to allow the browser process
+  // to put child processes into a job on Win7, which does not support
+  // nested jobs.  See CanUseJob() in sandboxBroker.cpp.
+  JOBOBJECT_EXTENDED_LIMIT_INFORMATION jobInfo = {};
+  jobInfo.BasicLimitInformation.LimitFlags =
+      JOB_OBJECT_LIMIT_KILL_ON_JOB_CLOSE | JOB_OBJECT_LIMIT_BREAKAWAY_OK;
+  if (!::SetInformationJobObject(job.get(), JobObjectExtendedLimitInformation,
+                                 &jobInfo, sizeof(jobInfo))) {
+    return empty.out();
+  }
+
+  if (!::AssignProcessToJobObject(job.get(), aProcess)) {
+    return empty.out();
+  }
+
+  return job.out();
+}
+
+#if !defined( \
+    PROCESS_CREATION_MITIGATION_POLICY_IMAGE_LOAD_PREFER_SYSTEM32_ALWAYS_ON)
+#  define PROCESS_CREATION_MITIGATION_POLICY_IMAGE_LOAD_PREFER_SYSTEM32_ALWAYS_ON \
+    (0x00000001ULL << 60)
+#endif  // !defined(PROCESS_CREATION_MITIGATION_POLICY_IMAGE_LOAD_PREFER_SYSTEM32_ALWAYS_ON)
+
+#if !defined(PROCESS_CREATION_MITIGATION_POLICY_CONTROL_FLOW_GUARD_ALWAYS_OFF)
+#  define PROCESS_CREATION_MITIGATION_POLICY_CONTROL_FLOW_GUARD_ALWAYS_OFF \
+    (0x00000002ULL << 40)
+#endif  // !defined(PROCESS_CREATION_MITIGATION_POLICY_CONTROL_FLOW_GUARD_ALWAYS_OFF)
+
+#if (_WIN32_WINNT < 0x0602)
+BOOL WINAPI
+SetProcessMitigationPolicy(PROCESS_MITIGATION_POLICY aMitigationPolicy,
+                           PVOID aBuffer, SIZE_T aBufferLen);
+#endif  // (_WIN32_WINNT >= 0x0602)
+
+/**
+ * Any mitigation policies that should be set on the browser process should go
+ * here.
+ */
+static void SetMitigationPolicies(mozilla::ProcThreadAttributes& aAttrs,
+                                  const bool aIsSafeMode) {
+  if (mozilla::IsWin10AnniversaryUpdateOrLater()) {
+    aAttrs.AddMitigationPolicy(
+        PROCESS_CREATION_MITIGATION_POLICY_IMAGE_LOAD_PREFER_SYSTEM32_ALWAYS_ON);
+  }
+
+#if defined(_M_ARM64)
+  // Disable CFG on older versions of ARM64 Windows to avoid a crash in COM.
+  if (!mozilla::IsWin10Sep2018UpdateOrLater()) {
+    aAttrs.AddMitigationPolicy(
+        PROCESS_CREATION_MITIGATION_POLICY_CONTROL_FLOW_GUARD_ALWAYS_OFF);
+  }
+#endif  // defined(_M_ARM64)
+}
+
+static mozilla::LauncherFlags ProcessCmdLine(int& aArgc, wchar_t* aArgv[]) {
+  mozilla::LauncherFlags result = mozilla::LauncherFlags::eNone;
+
+  if (mozilla::CheckArg(aArgc, aArgv, "wait-for-browser", nullptr,
+                        mozilla::CheckArgFlag::RemoveArg) ==
+          mozilla::ARG_FOUND ||
+      mozilla::CheckArg(aArgc, aArgv, "marionette", nullptr,
+                        mozilla::CheckArgFlag::None) == mozilla::ARG_FOUND ||
+      mozilla::CheckArg(aArgc, aArgv, "backgroundtask", nullptr,
+                        mozilla::CheckArgFlag::None) == mozilla::ARG_FOUND ||
+      mozilla::CheckArg(aArgc, aArgv, "headless", nullptr,
+                        mozilla::CheckArgFlag::None) == mozilla::ARG_FOUND ||
+      mozilla::CheckArg(aArgc, aArgv, "remote-debugging-port", nullptr,
+                        mozilla::CheckArgFlag::None) == mozilla::ARG_FOUND ||
+      mozilla::EnvHasValue("MOZ_AUTOMATION") ||
+      mozilla::EnvHasValue("MOZ_HEADLESS")) {
+    result |= mozilla::LauncherFlags::eWaitForBrowser;
+  }
+
+  if (mozilla::CheckArg(aArgc, aArgv, "no-deelevate") == mozilla::ARG_FOUND) {
+    result |= mozilla::LauncherFlags::eNoDeelevate;
+  }
+
+  if (mozilla::CheckArg(aArgc, aArgv, ATTEMPTING_DEELEVATION_FLAG) ==
+      mozilla::ARG_FOUND) {
+    result |= mozilla::LauncherFlags::eDeelevating;
+  }
+
+  return result;
+}
+
+static void MaybeBreakForBrowserDebugging() {
+  if (mozilla::EnvHasValue("MOZ_DEBUG_BROWSER_PROCESS")) {
+    ::DebugBreak();
+    return;
+  }
+
+  const wchar_t* pauseLenS = _wgetenv(L"MOZ_DEBUG_BROWSER_PAUSE");
+  if (!pauseLenS || !(*pauseLenS)) {
+    return;
+  }
+
+  DWORD pauseLenMs = wcstoul(pauseLenS, nullptr, 10) * 1000;
+  printf_stderr("\n\nBROWSERBROWSERBROWSERBROWSER\n  debug me @ %lu\n\n",
+                ::GetCurrentProcessId());
+  ::Sleep(pauseLenMs);
+}
+
+static bool DoLauncherProcessChecks(int& argc, wchar_t** argv) {
+  // NB: We run all tests in this function instead of returning early in order
+  // to ensure that all side effects take place, such as clearing environment
+  // variables.
+  bool result = false;
+
+#if defined(MOZ_LAUNCHER_PROCESS)
+  // We still prefer to compare file ids.  Comparing NT paths i.e. passing
+  // CompareNtPathsOnly to IsSameBinaryAsParentProcess is much faster, but
+  // we're not 100% sure that NT path comparison perfectly prevents the
+  // launching loop of the launcher process.
+  mozilla::LauncherResult<bool> isSame = mozilla::IsSameBinaryAsParentProcess();
+  if (isSame.isOk()) {
+    result = !isSame.unwrap();
+  } else {
+    HandleLauncherError(isSame.unwrapErr());
+  }
+#endif  // defined(MOZ_LAUNCHER_PROCESS)
+
+  if (mozilla::EnvHasValue("MOZ_LAUNCHER_PROCESS")) {
+    mozilla::SaveToEnv("MOZ_LAUNCHER_PROCESS=");
+    result = true;
+  }
+
+  result |=
+      mozilla::CheckArg(argc, argv, "launcher", nullptr,
+                        mozilla::CheckArgFlag::RemoveArg) == mozilla::ARG_FOUND;
+
+  return result;
+}
+
+#if defined(MOZ_LAUNCHER_PROCESS)
+static mozilla::Maybe<bool> RunAsLauncherProcess(
+    mozilla::LauncherRegistryInfo& aRegInfo, int& argc, wchar_t** argv) {
+#else
+static mozilla::Maybe<bool> RunAsLauncherProcess(int& argc, wchar_t** argv) {
+#endif  // defined(MOZ_LAUNCHER_PROCESS)
+  bool runAsLauncher = DoLauncherProcessChecks(argc, argv);
+
+#if defined(MOZ_LAUNCHER_PROCESS)
+  bool forceLauncher =
+      runAsLauncher &&
+      mozilla::CheckArg(argc, argv, "force-launcher", nullptr,
+                        mozilla::CheckArgFlag::RemoveArg) == mozilla::ARG_FOUND;
+
+  mozilla::LauncherRegistryInfo::ProcessType desiredType =
+      runAsLauncher ? mozilla::LauncherRegistryInfo::ProcessType::Launcher
+                    : mozilla::LauncherRegistryInfo::ProcessType::Browser;
+
+  mozilla::LauncherRegistryInfo::CheckOption checkOption =
+      forceLauncher ? mozilla::LauncherRegistryInfo::CheckOption::Force
+                    : mozilla::LauncherRegistryInfo::CheckOption::Default;
+
+  mozilla::LauncherResult<mozilla::LauncherRegistryInfo::ProcessType>
+      runAsType = aRegInfo.Check(desiredType, checkOption);
+
+  if (runAsType.isErr()) {
+    mozilla::HandleLauncherError(runAsType);
+    return mozilla::Nothing();
+  }
+
+  runAsLauncher = runAsType.unwrap() ==
+                  mozilla::LauncherRegistryInfo::ProcessType::Launcher;
+#endif  // defined(MOZ_LAUNCHER_PROCESS)
+
+  if (!runAsLauncher) {
+    // In this case, we will be proceeding to run as the browser.
+    // We should check MOZ_DEBUG_BROWSER_* env vars.
+    MaybeBreakForBrowserDebugging();
+  }
+
+  return mozilla::Some(runAsLauncher);
+}
+
+namespace mozilla {
+
+Maybe<int> LauncherMain(int& argc, wchar_t* argv[],
+                        const StaticXREAppData& aAppData) {
+  EnsureBrowserCommandlineSafe(argc, argv);
+
+  SetLauncherErrorAppData(aAppData);
+
+  if (CheckArg(argc, argv, "log-launcher-error", nullptr,
+               mozilla::CheckArgFlag::RemoveArg) == ARG_FOUND) {
+    SetLauncherErrorForceEventLog();
+  }
+
+  // return fast when we're a child process.
+  // (The remainder of this function has some side effects that are
+  // undesirable for content processes)
+  if (mozilla::CheckArg(argc, argv, "contentproc", nullptr,
+                        mozilla::CheckArgFlag::None) == mozilla::ARG_FOUND) {
+    // A child process should not instantiate LauncherRegistryInfo.
+    return Nothing();
+  }
+
+#if defined(MOZ_LAUNCHER_PROCESS)
+  LauncherRegistryInfo regInfo;
+  Maybe<bool> runAsLauncher = RunAsLauncherProcess(regInfo, argc, argv);
+  LauncherResult<std::wstring> blocklistFileNameResult =
+      regInfo.GetBlocklistFileName();
+  Maybe<std::wstring> blocklistFileName =
+      blocklistFileNameResult.isOk() ? Some(blocklistFileNameResult.unwrap())
+                                     : Nothing();
+#else
+  Maybe<bool> runAsLauncher = RunAsLauncherProcess(argc, argv);
+  Maybe<std::wstring> blocklistFileName = Nothing();
+#endif  // defined(MOZ_LAUNCHER_PROCESS)
+  if (!runAsLauncher || !runAsLauncher.value()) {
+#if defined(MOZ_LAUNCHER_PROCESS)
+    // Update the registry as Browser
+    LauncherVoidResult commitResult = regInfo.Commit();
+    if (commitResult.isErr()) {
+      mozilla::HandleLauncherError(commitResult);
+    }
+#endif  // defined(MOZ_LAUNCHER_PROCESS)
+    return Nothing();
+  }
+
+  // Make sure that the launcher process itself has image load policies set
+  if (IsWin10AnniversaryUpdateOrLater()) {
+    static const StaticDynamicallyLinkedFunctionPtr<
+        decltype(&SetProcessMitigationPolicy)>
+        pSetProcessMitigationPolicy(L"kernel32.dll",
+                                    "SetProcessMitigationPolicy");
+    if (pSetProcessMitigationPolicy) {
+      PROCESS_MITIGATION_IMAGE_LOAD_POLICY imgLoadPol = {};
+      imgLoadPol.PreferSystem32Images = 1;
+
+      DebugOnly<BOOL> setOk = pSetProcessMitigationPolicy(
+          ProcessImageLoadPolicy, &imgLoadPol, sizeof(imgLoadPol));
+      MOZ_ASSERT(setOk);
+    }
+  }
+
+#if defined(MOZ_SANDBOX)
+  // Ensure the relevant mitigations are enforced.
+  mozilla::sandboxing::ApplyParentProcessMitigations();
+#endif
+
+  mozilla::UseParentConsole();
+
+  if (!SetArgv0ToFullBinaryPath(argv)) {
+    HandleLauncherError(LAUNCHER_ERROR_GENERIC());
+    return Nothing();
+  }
+
+  LauncherFlags flags = ProcessCmdLine(argc, argv);
+
+  nsAutoHandle mediumIlToken;
+  LauncherResult<ElevationState> elevationState =
+      GetElevationState(argv[0], flags, mediumIlToken);
+  if (elevationState.isErr()) {
+    HandleLauncherError(elevationState);
+    return Nothing();
+  }
+
+  // Distill deelevation status, and/or attempt to perform launcher deelevation
+  // via an indirect relaunch.
+  DeelevationStatus deelevationStatus = DeelevationStatus::Unknown;
+  if (mediumIlToken.get()) {
+    // Rather than indirectly relaunch the launcher, we'll attempt to directly
+    // launch the main process with a reduced-privilege security token.
+    deelevationStatus = DeelevationStatus::PartiallyDeelevated;
+  } else if (elevationState.unwrap() == ElevationState::eElevated) {
+    if (flags & LauncherFlags::eWaitForBrowser) {
+      // An indirect relaunch won't provide a process-handle to block on,
+      // so we have to continue onwards with this process.
+      deelevationStatus = DeelevationStatus::DeelevationProhibited;
+    } else if (flags & LauncherFlags::eNoDeelevate) {
+      // Our invoker (hopefully, the user) has explicitly requested that the
+      // launcher not deelevate itself.
+      deelevationStatus = DeelevationStatus::DeelevationProhibited;
+    } else if (flags & LauncherFlags::eDeelevating) {
+      // We've already tried to deelevate, to no effect. Continue onward.
+      deelevationStatus = DeelevationStatus::UnsuccessfullyDeelevated;
+    } else {
+      // Otherwise, attempt to relaunch the launcher process itself via the
+      // shell, which hopefully will not be elevated. (But see bug 1733821.)
+      LauncherVoidResult launchedUnelevated = LaunchUnelevated(argc, argv);
+      if (launchedUnelevated.isErr()) {
+        // On failure, don't even try for a launcher process. Continue onwards
+        // in this one. (TODO: why? This isn't technically fatal...)
+        HandleLauncherError(launchedUnelevated);
+        return Nothing();
+      }
+      // Otherwise, tell our caller to exit with a success code.
+      return Some(0);
+    }
+  } else if (elevationState.unwrap() == ElevationState::eNormalUser) {
+    if (flags & LauncherFlags::eDeelevating) {
+      // Deelevation appears to have been successful!
+      deelevationStatus = DeelevationStatus::SuccessfullyDeelevated;
+    } else {
+      // We haven't done anything and we don't need to.
+      deelevationStatus = DeelevationStatus::StartedUnprivileged;
+    }
+  } else {
+    // Some other elevation state with no medium-integrity token.
+    // (This should probably not happen.)
+    deelevationStatus = DeelevationStatus::Unknown;
+  }
+
+#if defined(MOZ_LAUNCHER_PROCESS)
+  // Update the registry as Launcher
+  LauncherVoidResult commitResult = regInfo.Commit();
+  if (commitResult.isErr()) {
+    mozilla::HandleLauncherError(commitResult);
+    return Nothing();
+  }
+#endif  // defined(MOZ_LAUNCHER_PROCESS)
+
+  // Now proceed with setting up the parameters for process creation
+  UniquePtr<wchar_t[]> cmdLine(MakeCommandLine(argc, argv));
+  if (!cmdLine) {
+    HandleLauncherError(LAUNCHER_ERROR_GENERIC());
+    return Nothing();
+  }
+
+  const Maybe<bool> isSafeMode =
+      IsSafeModeRequested(argc, argv, SafeModeFlag::NoKeyPressCheck);
+  if (!isSafeMode) {
+    HandleLauncherError(LAUNCHER_ERROR_FROM_WIN32(ERROR_INVALID_PARAMETER));
+    return Nothing();
+  }
+
+  ProcThreadAttributes attrs;
+  SetMitigationPolicies(attrs, isSafeMode.value());
+
+  HANDLE stdHandles[] = {::GetStdHandle(STD_INPUT_HANDLE),
+                         ::GetStdHandle(STD_OUTPUT_HANDLE),
+                         ::GetStdHandle(STD_ERROR_HANDLE)};
+
+  attrs.AddInheritableHandles(stdHandles);
+
+  DWORD creationFlags = CREATE_SUSPENDED | CREATE_UNICODE_ENVIRONMENT;
+
+  STARTUPINFOEXW siex;
+  LauncherResult<bool> attrsOk = attrs.AssignTo(siex);
+  if (attrsOk.isErr()) {
+    HandleLauncherError(attrsOk);
+    return Nothing();
+  }
+
+  BOOL inheritHandles = FALSE;
+
+  if (attrsOk.unwrap()) {
+    creationFlags |= EXTENDED_STARTUPINFO_PRESENT;
+
+    if (attrs.HasInheritableHandles()) {
+      siex.StartupInfo.dwFlags |= STARTF_USESTDHANDLES;
+      siex.StartupInfo.hStdInput = stdHandles[0];
+      siex.StartupInfo.hStdOutput = stdHandles[1];
+      siex.StartupInfo.hStdError = stdHandles[2];
+
+      // Since attrsOk == true, we have successfully set the handle inheritance
+      // whitelist policy, so only the handles added to attrs will be inherited.
+      inheritHandles = TRUE;
+    }
+  }
+
+  // Pass on the path of the shortcut used to launch this process, if any.
+  STARTUPINFOW currentStartupInfo = {.cb = sizeof(STARTUPINFOW)};
+  GetStartupInfoW(&currentStartupInfo);
+  if ((currentStartupInfo.dwFlags & STARTF_TITLEISLINKNAME) &&
+      currentStartupInfo.lpTitle) {
+    siex.StartupInfo.dwFlags |= STARTF_TITLEISLINKNAME;
+    siex.StartupInfo.lpTitle = currentStartupInfo.lpTitle;
+  }
+
+  PROCESS_INFORMATION pi = {};
+  BOOL createOk;
+
+  if (mediumIlToken.get()) {
+    createOk =
+        ::CreateProcessAsUserW(mediumIlToken.get(), argv[0], cmdLine.get(),
+                               nullptr, nullptr, inheritHandles, creationFlags,
+                               nullptr, nullptr, &siex.StartupInfo, &pi);
+  } else {
+    createOk = ::CreateProcessW(argv[0], cmdLine.get(), nullptr, nullptr,
+                                inheritHandles, creationFlags, nullptr, nullptr,
+                                &siex.StartupInfo, &pi);
+  }
+
+  if (!createOk) {
+    HandleLauncherError(LAUNCHER_ERROR_FROM_LAST());
+    return Nothing();
+  }
+
+  nsAutoHandle process(pi.hProcess);
+  nsAutoHandle mainThread(pi.hThread);
+
+  nsAutoHandle job;
+  if (flags & LauncherFlags::eWaitForBrowser) {
+    job = CreateJobAndAssignProcess(process.get());
+  }
+
+  bool disableDynamicBlocklist = IsDynamicBlocklistDisabled(
+      isSafeMode.value(),
+      mozilla::CheckArg(
+          argc, argv, mozilla::geckoargs::sDisableDynamicDllBlocklist.sMatch,
+          nullptr, mozilla::CheckArgFlag::None) == mozilla::ARG_FOUND);
+  LauncherVoidResult setupResult = PostCreationSetup(
+      argv[0], process.get(), mainThread.get(), deelevationStatus,
+      isSafeMode.value(), disableDynamicBlocklist, blocklistFileName);
+  if (setupResult.isErr()) {
+    HandleLauncherError(setupResult);
+    ::TerminateProcess(process.get(), 1);
+    return Nothing();
+  }
+
+  if (::ResumeThread(mainThread.get()) == static_cast<DWORD>(-1)) {
+    HandleLauncherError(LAUNCHER_ERROR_FROM_LAST());
+    ::TerminateProcess(process.get(), 1);
+    return Nothing();
+  }
+
+  if (flags & LauncherFlags::eWaitForBrowser) {
+    DWORD exitCode;
+    if (::WaitForSingleObject(process.get(), INFINITE) == WAIT_OBJECT_0 &&
+        ::GetExitCodeProcess(process.get(), &exitCode)) {
+      // Propagate the browser process's exit code as our exit code.
+      return Some(static_cast<int>(exitCode));
+    }
+  } else {
+    const DWORD timeout =
+        ::IsDebuggerPresent() ? INFINITE : kWaitForInputIdleTimeoutMS;
+
+    // Keep the current process around until the callback process has created
+    // its message queue, to avoid the launched process's windows being forced
+    // into the background.
+    mozilla::WaitForInputIdle(process.get(), timeout);
+  }
+
+  return Some(0);
+}
+
+}  // namespace mozilla