path: root/drivers/video/fbmem.c
diff options
authorFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>2009-09-22 23:47:41 (GMT)
committerLinus Torvalds <torvalds@linux-foundation.org>2009-09-23 14:39:56 (GMT)
commit99e9e7d62becd6c7413a9e8fbda7f5b66adb5cbf (patch)
tree63ffee25ae6f56a41ff227aea44556a2d16ee907 /drivers/video/fbmem.c
parentff8147fe71246b81a48de5f37041b026b57d60ca (diff)
fb: fix fb_pan_display range check
Fix the range check for panning. The current code fails to detect some invalid values (very high ones that can occur if an app tries to move further up/left than 0,0) as the check uses the unknown values for calculation so that an overflow can occur. To fix this it is sufficient to move the calculation to the right side to use only trusted values. Kai Jiang detected this problem and proposed an initial patch. Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de> Cc: Kai Jiang <b18973@freescale.com> Cc: Krzysztof Helt <krzysztof.h1@poczta.fm> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/video/fbmem.c')
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/video/fbmem.c b/drivers/video/fbmem.c
index a85c818..346f257 100644
--- a/drivers/video/fbmem.c
+++ b/drivers/video/fbmem.c
@@ -871,8 +871,8 @@ fb_pan_display(struct fb_info *info, struct fb_var_screeninfo *var)
err = -EINVAL;
if (err || !info->fbops->fb_pan_display ||
- var->yoffset + yres > info->var.yres_virtual ||
- var->xoffset + info->var.xres > info->var.xres_virtual)
+ var->yoffset > info->var.yres_virtual - yres ||
+ var->xoffset > info->var.xres_virtual - info->var.xres)
return -EINVAL;
if ((err = info->fbops->fb_pan_display(var, info)))

Privacy Policy