lkml.org 
[lkml]   [2010]   [Nov]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [Security] [PATCH] Restrict unprivileged access to kernel syslog
From
On Tue, Nov 9, 2010 at 1:34 PM, Kees Cook <kees.cook@canonical.com> wrote:
> On Mon, Nov 08, 2010 at 10:28:58PM -0500, Dan Rosenberg wrote:
>> The kernel syslog contains debugging information that is often useful
>> during exploitation of other vulnerabilities, such as kernel heap
>> addresses.  Rather than futilely attempt to sanitize hundreds (or
>> thousands) of printk statements and simultaneously cripple useful
>> debugging functionality, it is far simpler to create an option that
>> prevents unprivileged users from reading the syslog.
>>
>> This patch, loosely based on grsecurity's GRKERNSEC_DMESG, creates the
>> dmesg_restrict sysctl.  When set to "0", the default, no restrictions
>> are enforced.  When set to "1", only users with CAP_SYS_ADMIN can read
>> the kernel syslog via dmesg(8) or other mechanisms.
>>
>> Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com>
>
> Acked-by: Kees Cook <kees.cook@canonical.com>
>
> This looks good to me -- it leaves the /proc file access alone for
> priv-dropping ksyslogd implementations.

Acked-by: Eugene Teo <eugeneteo@kernel.org>

Looks good to me too. Thanks.

Eugene
--
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: 2010-11-09 06:41    [W:2.040 / U:0.020 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site