taskmgr is not threadsafe

Taskmgr uses an update thread that deletes structures containing task information from the heap when the task is no longer present.
At the same time the gui thread could access these structures on a response to clicking an item. There is no synchronisation mechanism.

Thread 1 (update thread)
in procpage.c:452 (UpdateProcesses())

(void)ListView_GetItem(hProcessPageListCtrl, &item);
pData = (LPPROCESS_PAGE_LIST_ITEM)item.lParam;
if (!ProcessRunning(pData->ProcessId))

{ (void)ListView_DeleteItem(hProcessPageListCtrl, i); HeapFree(GetProcessHeap(), 0, pData); }

called from procpage.c:414 (ProcessPageRefreshThread())

Thread 0 (gui thread)
in procpage.c:244 (ProcessPageOnNotify())

case LVN_GETDISPINFO:

if (!(pnmdi->item.mask & LVIF_TEXT))
break;

pData = (LPPROCESS_PAGE_LIST_ITEM)pnmdi->item.lParam;
Index = PerfDataGetProcessIndex(pData->ProcessId);
ColumnIndex = pnmdi->item.iSubItem;

PerfDataGetText(Index, ColumnIndex, pnmdi->item.pszText, pnmdi->item.cchTextMax);