[ros-diffs] [jmorlan] 34358: IntGdiCreateBitmap: Tighten up parameter checks, preventing overflows; don't multiply by Planes twice in calculating WidthBytes. IntCreateCompatibleBitmap: Remove 65535px maximum (Windows has no such limit); return the stock 1x1 bitmap instead of creating a new one. BITMAPOBJ_GetRealBitsPixel: Change parameter type to UINT; remove 2bpp return (2bpp bitmaps are not actually supported)

Author: jmorlan
Date: Mon Jul  7 11:03:14 2008
New Revision: 34358

URL: http://svn.reactos.org/svn/reactos?rev=34358&view=rev
Log:
IntGdiCreateBitmap: Tighten up parameter checks, preventing overflows; don't multiply
by Planes twice in calculating WidthBytes.
IntCreateCompatibleBitmap: Remove 65535px maximum (Windows has no such limit); return the
stock 1x1 bitmap instead of creating a new one.
BITMAPOBJ_GetRealBitsPixel: Change parameter type to UINT; remove 2bpp return (2bpp
bitmaps are not actually supported)

Modified:
    trunk/reactos/subsystems/win32/win32k/include/bitmaps.h
    trunk/reactos/subsystems/win32/win32k/objects/bitmaps.c

Modified: trunk/reactos/subsystems/win32/win32k/include/bitmaps.h
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/subsystems/win32/win32k/in…
==============================================================================
--- trunk/reactos/subsystems/win32/win32k/include/bitmaps.h [iso-8859-1] (original)
+++ trunk/reactos/subsystems/win32/win32k/include/bitmaps.h [iso-8859-1] Mon Jul  7
11:03:14 2008
@@ -53,7 +53,7 @@
 void INTERNAL_CALL BITMAPOBJ_CleanupBitsLock(BITMAPOBJ *pBMObj);
 
 INT     FASTCALL BITMAPOBJ_GetWidthBytes (INT bmWidth, INT bpp);
-INT     FASTCALL BITMAPOBJ_GetRealBitsPixel(INT nBitsPixel);
+UINT    FASTCALL BITMAPOBJ_GetRealBitsPixel(UINT nBitsPixel);
 HBITMAP FASTCALL BITMAPOBJ_CopyBitmap (HBITMAP  hBitmap);
 INT     FASTCALL DIB_GetDIBWidthBytes (INT  width, INT  depth);
 int     NTAPI  DIB_GetDIBImageBytes (INT  width, INT  height, INT  depth);

Modified: trunk/reactos/subsystems/win32/win32k/objects/bitmaps.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/subsystems/win32/win32k/ob…
==============================================================================
--- trunk/reactos/subsystems/win32/win32k/objects/bitmaps.c [iso-8859-1] (original)
+++ trunk/reactos/subsystems/win32/win32k/objects/bitmaps.c [iso-8859-1] Mon Jul  7
11:03:14 2008
@@ -47,17 +47,25 @@
    BitsPixel = BITMAPOBJ_GetRealBitsPixel(BitsPixel * Planes);
 
    /* Check parameters */
-   if (BitsPixel == 0 || Width < 0)
+   if (BitsPixel == 0 || Width <= 0 || Width >= 0x8000000 || Height == 0)
    {
       DPRINT1("Width = %d, Height = %d BitsPixel = %d\n", Width, Height,
BitsPixel);
       SetLastWin32Error(ERROR_INVALID_PARAMETER);
       return 0;
    }
 
-   WidthBytes = BITMAPOBJ_GetWidthBytes(Width, Planes * BitsPixel);
-
-   Size.cx = abs(Width);
+   WidthBytes = BITMAPOBJ_GetWidthBytes(Width, BitsPixel);
+
+   Size.cx = Width;
    Size.cy = abs(Height);
+
+   /* Make sure that cjBits will not overflow */
+   if ((ULONGLONG)WidthBytes * Size.cy >= 0x100000000ULL)
+   {
+      DPRINT1("Width = %d, Height = %d BitsPixel = %d\n", Width, Height,
BitsPixel);
+      SetLastWin32Error(ERROR_INVALID_PARAMETER);
+      return 0;
+   }
 
    /* Create the bitmap object. */
    hBitmap = IntCreateBitmap(Size, WidthBytes,
@@ -166,18 +174,10 @@
 {
 	HBITMAP Bmp;
 
-	Bmp = NULL;
-
-	if ((Width >= 0x10000) || (Height >= 0x10000))
-	{
-		DPRINT1("got bad width %d or height %d, please look for reason\n", Width,
Height);
-		return NULL;
-	}
-
 	/* MS doc says if width or height is 0, return 1-by-1 pixel, monochrome bitmap */
 	if (0 == Width || 0 == Height)
 	{
-		Bmp = IntGdiCreateBitmap (1, 1, 1, 1, NULL);
+		Bmp = NtGdiGetStockObject(DEFAULT_BITMAP);
 	}
 	else
 	{
@@ -602,15 +602,11 @@
 
 /*  Internal Functions  */
 
-INT FASTCALL
-BITMAPOBJ_GetRealBitsPixel(INT nBitsPixel)
-{
-	if (nBitsPixel < 0)
-		return 0;
+UINT FASTCALL
+BITMAPOBJ_GetRealBitsPixel(UINT nBitsPixel)
+{
 	if (nBitsPixel <= 1)
 		return 1;
-	if (nBitsPixel <= 2)
-		return 2;
 	if (nBitsPixel <= 4)
 		return 4;
 	if (nBitsPixel <= 8)