lkml.org 
[lkml]   [2006]   [Apr]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [patch 03/26] sysfs: zero terminate sysfs write buffers (CVE-2006-1055)
On 4/5/06, Al Viro <viro@ftp.linux.org.uk> wrote:
> On Wed, Apr 05, 2006 at 07:09:28PM +0400, Sergey Vlasov wrote:
> > This will break the "color_map" sysfs file for framebuffers -
> > drivers/video/fbsysfs.c:store_cmap() expects to get exactly 4096 bytes
> > for a colormap with 256 entries. In fact, the original patch which
> > changed PAGE_SIZE - 1 to PAGE_SIZE:
>
> ... cheerfully assuming that nobody assumes NUL-termination and
> everyone (sysfs patch writers!) certainly uses the length argument.
> Fscking brilliant, that.

Why does sysfs have two string length determination methods - both
NULL termination and a length parameter. It should be one or the
other, not both. Having both simply cause problems when some
developers implement one scheme and others only implement the other.


>
> Are you willing to audit all sysfs ->show() in the kernel? Original
> author of that turd had not been.
>
> FWIW, "color_map" is a blatant abuse of interface. Doesn't get
> any more borderline...
>
>


--
Jon Smirl
jonsmirl@gmail.com
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2006-04-05 18:40    [W:0.089 / U:0.624 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site