From 3e75942b109a5408cf0c4a8184537f847263272c Mon Sep 17 00:00:00 2001
From: Timo Kreuzer <timo.kreuzer@reactos.org>
Date: Sat, 19 Feb 2011 22:29:31 +0000
Subject: [PATCH] [WIN32K] NtGdiStretchDIBitsInternal: don't call
 NtGdiGetDCObject and NtGdiCreateCompatibleDC with a dc locked. These cases
 are not harmful, but generally Nt* and Gre* should never be called with an
 exclusive gdi lock held. Also don't return in failure case with the dc still
 locked.

svn path=/trunk/; revision=50826
---
 .../subsystems/win32/win32k/objects/dibobj.c  | 20 ++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/reactos/subsystems/win32/win32k/objects/dibobj.c b/reactos/subsystems/win32/win32k/objects/dibobj.c
index 1dfa5344ad8..f33a8bc4ab5 100644
--- a/reactos/subsystems/win32/win32k/objects/dibobj.c
+++ b/reactos/subsystems/win32/win32k/objects/dibobj.c
@@ -1043,13 +1043,6 @@ NtGdiStretchDIBitsInternal(
         return 0;
     }
 
-    if (!(pdc = DC_LockDc(hDC)))
-    {
-        ExFreePoolWithTag(safeBits, TAG_DIB);
-        EngSetLastError(ERROR_INVALID_HANDLE);
-        return 0;
-    }
-
     _SEH2_TRY
     {
         ProbeForRead(BitsInfo, cjMaxInfo, 1);
@@ -1076,6 +1069,13 @@ NtGdiStretchDIBitsInternal(
 
     hBitmap = NtGdiGetDCObject(hDC, OBJ_BITMAP);
 
+    if (!(pdc = DC_LockDc(hDC)))
+    {
+        ExFreePoolWithTag(safeBits, TAG_DIB);
+        EngSetLastError(ERROR_INVALID_HANDLE);
+        return 0;
+    }
+
     if (XDest == 0 && YDest == 0 && XSrc == 0 && XSrc == 0 &&
         DestWidth == SrcWidth && DestHeight == SrcHeight &&
         compr == BI_RGB &&
@@ -1091,14 +1091,17 @@ NtGdiStretchDIBitsInternal(
         {
             /* fast path */
             ret = IntSetDIBits(pdc, hBitmap, 0, height, safeBits, BitsInfo, Usage);
+            DC_UnlockDc(pdc);
             goto cleanup;
         }
     }
 
     /* slow path - need to use StretchBlt */
 
-    hdcMem = NtGdiCreateCompatibleDC(hDC);
     hBitmap = DIB_CreateDIBSection(pdc, BitsInfo, Usage, &pvBits, NULL, 0, 0);
+    DC_UnlockDc(pdc);
+
+    hdcMem = NtGdiCreateCompatibleDC(hDC);
     if(!hBitmap)
     {
         DPRINT1("Error, failed to create a DIB section\n");
@@ -1123,7 +1126,6 @@ NtGdiStretchDIBitsInternal(
 
 cleanup:
     ExFreePoolWithTag(safeBits, TAG_DIB);
-    DC_UnlockDc(pdc);
     return ret;
 }