From 72bceaffc2850de2c6cba13ed2772c550be2de1c Mon Sep 17 00:00:00 2001
From: Timo Kreuzer <timo.kreuzer@reactos.org>
Date: Thu, 18 Dec 2014 08:12:28 +0000
Subject: [PATCH] [WIN32K] Implement exclusive lock order checks for GDI
 objects in debug builds

svn path=/trunk/; revision=65731
---
 reactos/win32ss/gdi/ntgdi/gdiobj.c | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/reactos/win32ss/gdi/ntgdi/gdiobj.c b/reactos/win32ss/gdi/ntgdi/gdiobj.c
index 8aa9703b760..c03d5c14d44 100644
--- a/reactos/win32ss/gdi/ntgdi/gdiobj.c
+++ b/reactos/win32ss/gdi/ntgdi/gdiobj.c
@@ -71,6 +71,22 @@ DECREASE_THREAD_LOCK_COUNT(
 }
 
 #if DBG
+VOID
+ASSERT_LOCK_ORDER(
+    _In_ UCHAR objt)
+{
+    PTHREADINFO pti = PsGetCurrentThreadWin32Thread();
+    ULONG i;
+
+    if (pti)
+    {
+        /* Ensure correct locking order! */
+        for (i = objt + 1; i < GDIObjTypeTotal; i++)
+        {
+            NT_ASSERT(pti->acExclusiveLockCount[i] == 0);
+        }
+    }
+}
 #define ASSERT_SHARED_OBJECT_TYPE(objt) \
     ASSERT((objt) == GDIObjType_SURF_TYPE || \
            (objt) == GDIObjType_PAL_TYPE || \
@@ -83,6 +99,7 @@ DECREASE_THREAD_LOCK_COUNT(
 #define ASSERT_TRYLOCK_OBJECT_TYPE(objt) \
     ASSERT((objt) == GDIObjType_DRVOBJ_TYPE)
 #else
+#define ASSERT_LOCK_ORDER(hobj)
 #define ASSERT_SHARED_OBJECT_TYPE(objt)
 #define ASSERT_EXCLUSIVE_OBJECT_TYPE(objt)
 #define ASSERT_TRYLOCK_OBJECT_TYPE(objt)
@@ -669,6 +686,9 @@ GDIOBJ_TryLockObject(
         return NULL;
     }
 
+    /* Make sure lock order is correct */
+    ASSERT_LOCK_ORDER(objt);
+
     /* Reference the handle entry */
     pentry = ENTRY_ReferenceEntryByHandle(hobj, 0);
     if (!pentry)
@@ -735,6 +755,9 @@ GDIOBJ_LockObject(
         return NULL;
     }
 
+    /* Make sure lock order is correct */
+    ASSERT_LOCK_ORDER(objt);
+
     /* Reference the handle entry */
     pentry = ENTRY_ReferenceEntryByHandle(hobj, 0);
     if (!pentry)