Messages in this thread Patch in this message | | | From | Vasiliy Kulikov <> | Subject | [PATCH] video: arcfb: fix buffer overflow | Date | Sun, 21 Nov 2010 20:40:01 +0300 |
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(count + p) is not checked for integer overflow. If p < fbmemlength and count == (size_t)(1 - p) (very big unsigned integer) then count + p == 1 < fbmemlength and copy_to_user(base_addr+p, buf, count) overflows base_addr.
Signed-off-by: Vasiliy Kulikov <segoon@openwall.com> --- Compile tested only.
drivers/video/arcfb.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/drivers/video/arcfb.c b/drivers/video/arcfb.c index 3ec4923..67a4cd4 100644 --- a/drivers/video/arcfb.c +++ b/drivers/video/arcfb.c @@ -454,7 +454,7 @@ static ssize_t arcfb_write(struct fb_info *info, const char __user *buf, xres = info->var.xres; fbmemlength = (xres * info->var.yres)/8; - if (p > fbmemlength) + if (p > fbmemlength || (p + count < p)) return -ENOSPC; err = 0; -- 1.7.0.4
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