gh-125315: Avoid crashing in _wmimodule due to slow WMI calls on some Windows machines (GH-126141)

Author: zooba

Misc/NEWS.d/next/Windows/2024-10-29-19-48-03.gh-issue-125315.jdB9qN.rst

@@ -0,0 +1,2 @@
+Avoid crashing in :mod:`platform` due to slow WMI calls on some Windows
+machines.

PC/_wmimodule.cpp

@@ -55,12 +55,26 @@ _query_thread(LPVOID param)
  IWbemLocator *locator = NULL;
  IWbemServices *services = NULL;
  IEnumWbemClassObject* enumerator = NULL;
+ HRESULT hr = S_OK;
  BSTR bstrQuery = NULL;
  struct _query_data *data = (struct _query_data*)param;
 
- HRESULT hr = CoInitializeEx(nullptr, COINIT_APARTMENTTHREADED);
+ // gh-125315: Copy the query string first, so that if the main thread gives
+ // up on waiting we aren't left with a dangling pointer (and a likely crash)
+ bstrQuery = SysAllocString(data->query);
+ if (!bstrQuery) {
+ hr = HRESULT_FROM_WIN32(ERROR_NOT_ENOUGH_MEMORY);
+ }
+
+ if (SUCCEEDED(hr)) {
+ hr = CoInitializeEx(nullptr, COINIT_APARTMENTTHREADED);
+ }
+
  if (FAILED(hr)) {
  CloseHandle(data->writePipe);
+ if (bstrQuery) {
+ SysFreeString(bstrQuery);
+ }
  return (DWORD)hr;
  }
 
@@ -101,12 +115,6 @@ _query_thread(LPVOID param)
  NULL, EOAC_NONE
  );
  }
- if (SUCCEEDED(hr)) {
- bstrQuery = SysAllocString(data->query);
- if (!bstrQuery) {
- hr = HRESULT_FROM_WIN32(ERROR_NOT_ENOUGH_MEMORY);
- }
- }
  if (SUCCEEDED(hr)) {
  hr = services->ExecQuery(
  bstr_t("WQL"),