[PATCH 2/3] gdi32: Check DIB size when handling EMR_ALPHABLEND.

[Vincent Povirk]

Signed-off-by: Vincent Povirk 
---
 dlls/gdi32/enhmetafile.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/dlls/gdi32/enhmetafile.c b/dlls/gdi32/enhmetafile.c
index d8f72c98718..c66e382c1d6 100644
--- a/dlls/gdi32/enhmetafile.c
+++ b/dlls/gdi32/enhmetafile.c
@@ -2559,12 +2559,26 @@ BOOL WINAPI PlayEnhMetaFileRecord(
             HBITMAP hBmp = 0, hBmpOld = 0;
             const BITMAPINFO *pbi = (const BITMAPINFO *)((const BYTE *)mr + pAlphaBlend->offBmiSrc);
             void *bits;
+            DIBSECTION dib;

SetGraphicsMode(hdcSrc, GM_ADVANCED);
             SetWorldTransform(hdcSrc, &pAlphaBlend->xformSrc);

hBmp = CreateDIBSection(hdc, pbi, pAlphaBlend->iUsageSrc, &bits, NULL, 0);
-            memcpy(bits, (const BYTE *)mr + pAlphaBlend->offBitsSrc, pAlphaBlend->cbBitsSrc);
+            if (!hBmp)
+            {
+                WARN("EMR_ALPHABLEND: couldn't create DIB section\n");
+                return FALSE;
+            }
+
+            if (!GetObjectW(hBmp, sizeof(dib), &dib))
+            {
+                ERR("EMR_ALPHABLEND: couldn't get DIB object\n");
+                DeleteObject(hBmp);
+                return FALSE;
+            }
+            
+            memcpy(bits, (const BYTE *)mr + pAlphaBlend->offBitsSrc, min(pAlphaBlend->cbBitsSrc, dib.dsBmih.biSizeImage));
             hBmpOld = SelectObject(hdcSrc, hBmp);

GdiAlphaBlend(hdc, pAlphaBlend->xDest, pAlphaBlend->yDest, pAlphaBlend->cxDest, pAlphaBlend->cyDest,