1 files changed, 8 insertions, 3 deletions

diff --git a/drivers/video/tgafb.c b/drivers/video/tgafb.c
index d292a37ec7d6..5539f4d9cb74 100644
--- a/drivers/video/tgafb.c
+++ b/drivers/video/tgafb.c
@@ -5,7 +5,7 @@
  *      Copyright (C) 1997 Geert Uytterhoeven
  *      Copyright (C) 1999,2000 Martin Lucina, Tom Zerucha
  *      Copyright (C) 2002 Richard Henderson
- *      Copyright (C) 2006 Maciej W. Rozycki
+ *      Copyright (C) 2006, 2007  Maciej W. Rozycki
  *
  *  This file is subject to the terms and conditions of the GNU General Public
  *  License. See the file COPYING in the main directory of this archive for
@@ -13,6 +13,7 @@
  */
 
 #include <linux/bitrev.h>
+#include <linux/compiler.h>
 #include <linux/delay.h>
 #include <linux/device.h>
 #include <linux/errno.h>
@@ -654,6 +655,9 @@ tgafb_mono_imageblit(struct fb_info *info, const struct fb_image *image)
         line_length = info->fix.line_length;
         rincr = (width + 7) / 8;
 
+        /* A shift below cannot cope with.  */
+        if (unlikely(width == 0))
+                return;
         /* Crop the image to the screen.  */
         if (dx > vxres || dy > vyres)
                 return;
@@ -709,9 +713,10 @@ tgafb_mono_imageblit(struct fb_info *info, const struct fb_image *image)
                 unsigned long bwidth;
 
                 /* Handle common case of imaging a single character, in
-                   a font less than 32 pixels wide.  */
+                   a font less than or 32 pixels wide.  */
 
-                pixelmask = (1 << width) - 1;
+                /* Avoid a shift by 32; width > 0 implied.  */
+                pixelmask = (2ul << (width - 1)) - 1;
                 pixelmask <<= shift;
                 __raw_writel(pixelmask, regs_base + TGA_PIXELMASK_REG);
                 wmb();