Important: xen security and bug fix update

Synopsis

Important: xen security and bug fix update

Type/Severity

Security Advisory: Important

Topic

Updated xen packages that fix one security issue and two bugs are now
available for Red Hat Enterprise Linux 5.

The Red Hat Security Response Team has rated this update as having
important security impact. A Common Vulnerability Scoring System (CVSS)
base score, which gives a detailed severity rating, is available from the
CVE link in the References section.

Description

The xen packages contain administration tools and the xend service for
managing the kernel-xen kernel for virtualization on Red Hat Enterprise
Linux.

A heap overflow flaw was found in the way QEMU emulated the e1000 network
interface card. A privileged guest user in a virtual machine whose network
interface is configured to use the e1000 emulated driver could use this
flaw to crash QEMU or, possibly, escalate their privileges on the host.
(CVE-2012-0029)

Red Hat would like to thank Nicolae Mogoreanu for reporting this issue.

This update also fixes the following bugs:

• Adding support for jumbo frames introduced incorrect network device
  expansion when a bridge is created. The expansion worked correctly with the
  default configuration, but could have caused network setup failures when a
  user-defined network script was used. This update changes the expansion so
  network setup will not fail, even when a user-defined network script is
  used. (BZ#797191)
  
• A bug was found in xenconsoled, the Xen hypervisor console daemon. If
  timestamp logging for this daemon was enabled (using both the
  XENCONSOLED_TIMESTAMP_HYPERVISOR_LOG and XENCONSOLED_TIMESTAMP_GUEST_LOG
  options in "/etc/sysconfig/xend"), xenconsoled could crash if the guest
  emitted a lot of information to its serial console in a short period of
  time. Eventually, the guest would freeze after the console buffer was
  filled due to the crashed xenconsoled. Timestamp logging is disabled by
  default. (BZ#797836)
  

All xen users are advised to upgrade to these updated packages, which
contain backported patches to correct these issues. The system must be
rebooted for this update to take effect.

Solution

Before applying this update, make sure all previously-released errata
relevant to your system have been applied.

This update is available via the Red Hat Network. Details on how to
use the Red Hat Network to apply this update are available at
https://access.redhat.com/knowledge/articles/11258

Affected Products

• Red Hat Enterprise Linux Server 5 x86_64
• Red Hat Enterprise Linux Server 5 ia64
• Red Hat Enterprise Linux Server 5 i386
• Red Hat Enterprise Linux Workstation 5 x86_64
• Red Hat Enterprise Linux Workstation 5 i386
• Red Hat Enterprise Linux Desktop 5 x86_64
• Red Hat Enterprise Linux Desktop 5 i386
• Red Hat Enterprise Linux Server from RHUI 5 x86_64
• Red Hat Enterprise Linux Server from RHUI 5 i386

Fixes

• BZ - 772075 - CVE-2012-0029 qemu: e1000: process_tx_desc legacy mode packets heap overflow
• BZ - 797191 - xen-network-common.sh scripting typo

CVEs

• CVE-2012-0029

References

• https://access.redhat.com/security/updates/classification/#important