From cb199a866c01c5ac5d93b9648e165fb415eb1ac1 Mon Sep 17 00:00:00 2001
From: James Tabor <james.tabor@reactos.org>
Date: Fri, 16 Sep 2016 23:58:51 +0000
Subject: [PATCH] [NtUser] - Use desktop thread list to search for related
 active desktop threads. See CORE-11983.

svn path=/trunk/; revision=72699
---
 reactos/win32ss/user/ntuser/kbdlayout.c | 32 +++++++++++++++----------
 1 file changed, 19 insertions(+), 13 deletions(-)

diff --git a/reactos/win32ss/user/ntuser/kbdlayout.c b/reactos/win32ss/user/ntuser/kbdlayout.c
index b903b5f0f4d..bda95cc592d 100644
--- a/reactos/win32ss/user/ntuser/kbdlayout.c
+++ b/reactos/win32ss/user/ntuser/kbdlayout.c
@@ -450,31 +450,37 @@ HKL FASTCALL
 UserGetKeyboardLayout(
     DWORD dwThreadId)
 {
-    NTSTATUS Status;
-    PETHREAD pThread;
     PTHREADINFO pti;
+    PLIST_ENTRY ListEntry;
     PKL pKl;
-    HKL hKl;
+
+    pti = PsGetCurrentThreadWin32Thread();
 
     if (!dwThreadId)
     {
-        pti = PsGetCurrentThreadWin32Thread();
         pKl = pti->KeyboardLayout;
         return pKl ? pKl->hkl : NULL;
     }
 
-    Status = PsLookupThreadByThreadId((HANDLE)(DWORD_PTR)dwThreadId, &pThread);
-    if (!NT_SUCCESS(Status))
+    ListEntry = pti->rpdesk->PtiList.Flink;
+
+    //
+    // Search the Desktop Thread list for related Desktop active Threads.
+    //
+    while(ListEntry != &pti->rpdesk->PtiList)
     {
-        EngSetLastError(ERROR_INVALID_PARAMETER);
-        return NULL;
+        pti = CONTAINING_RECORD(ListEntry, THREADINFO, PtiLink);
+
+        if (PsGetThreadId(pti->pEThread) == UlongToHandle(dwThreadId))
+        {
+           pKl = pti->KeyboardLayout;
+           return pKl ? pKl->hkl : NULL;
+        }
+
+        ListEntry = ListEntry->Flink;
     }
 
-    pti = PsGetThreadWin32Thread(pThread);
-    pKl = pti->KeyboardLayout;
-    hKl = pKl ? pKl->hkl : NULL;
-    ObDereferenceObject(pThread);
-    return hKl;
+    return NULL;
 }
 
 /*