Openwall GNU/*/Linux - a small security-enhanced Linux distro for servers
[<prev] [next>] [day] [month] [year] [list]
Date: Wed, 16 Jan 2013 14:50:11 +0000
From: Xen.org security team <security@....org>
To: xen-announce@...ts.xen.org, xen-devel@...ts.xen.org,
 xen-users@...ts.xen.org, oss-security@...ts.openwall.com
CC: Xen.org security team <security@....org>
Subject: Xen Security Advisory 40 (CVE-2013-0190) - Linux stack corruption
 in xen_failsafe_callback for 32bit PVOPS guests.

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

             Xen Security Advisory CVE-2013-0190 / XSA-40

 Linux stack corruption in xen_failsafe_callback for 32bit PVOPS guests.

ISSUE DESCRIPTION
=================

xen_failsafe_callback incorrectly sets up its stack if an iret fault is
injected by the hypervisor.

IMPACT
======

Malicious or buggy unprivileged userspace can cause the guest kernel to
crash, or operate erroneously.

VULNERABLE SYSTEMS
==================

All 32bit PVOPS versions of Linux are affected, since the introduction
of Xen PVOPS support in 2.6.23.  Classic-Xen kernels are not vulnerable.

MITIGATION
==========

This can be mitigated by not running 32bit PVOPS Linux guests.

32bit classic-Xen guests, all 64bit PV guests and all HVM guests are
unaffected.

RESOLUTION
==========

Applying the appropriate attached patch resolves this issue.

xsa40.patch

$ sha256sum xsa40*.patch
b6aa67b4605f6088f757ca28093d265c71e456906619d81d129bf656944ed721  xsa40.patch
$
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.10 (GNU/Linux)

iQEcBAEBAgAGBQJQ9r4HAAoJEIP+FMlX6CvZhIMIAKa3l8CMZ4Di0gyp1cVi95es
0Pzq8qV5Qwla+NZEuz1O91UAxzwke8mrVsKK9PQCUVqdrmKbIrWjGX3b/KNIoa3d
hCGBd1wkTld7XmQxNfr+0BcfybqM92dww623rhv6G2jPaehOMVGWl28vomwkMU9E
iT/z2dqYJuAkcq6hobJ02tyfABl5sWNDE+HvI6EFxTptzeUGQtaPm9q6qbdbw1pT
InAae/VU7u+qAZTr0MY8kncFiK3206LvJX2Wq6YBI6LCFw4eaOvTFfJiAvFojqQb
nl5PT2KXH3IbiZEAiSOENBRiudkzxY0OfGyTnyuwsZuJa7SaI47pN1Sp5YtRPf0=
=9uNq
-----END PGP SIGNATURE-----

Download attachment "xsa40.patch" of type "application/octet-stream" (2107 bytes)

Powered by blists - more mailing lists

Your e-mail address:

Please check out the Open Source Software Security Wiki, which is counterpart to this mailing list.

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.