(RHSA-2014:1352) Moderate: libvirt security and bug fix update

The libvirt library is a C API for managing and interacting with the
virtualization capabilities of Linux and other operating systems.
In addition, libvirt provides tools for remote management of
virtualized systems.

An out-of-bounds read flaw was found in the way libvirt’s
qemuDomainGetBlockIoTune() function looked up the disk index in a
non-persistent (live) disk configuration while a persistent disk
configuration was being indexed. A remote attacker able to establish a
read-only connection to libvirtd could use this flaw to crash libvirtd or,
potentially, leak memory from the libvirtd process. (CVE-2014-3633)

A denial of service flaw was found in the way libvirt’s
virConnectListAllDomains() function computed the number of used domains.
A remote attacker able to establish a read-only connection to libvirtd
could use this flaw to make any domain operations within libvirt
unresponsive. (CVE-2014-3657)

The CVE-2014-3633 issue was discovered by Luyao Huang of Red Hat.

This update also fixes the following bug:

• Prior to this update, libvirt was setting the cpuset.mems parameter for
  domains with numatune/memory[nodeset] prior to starting them. As a
  consequence, domains with such a nodeset, which excluded the NUMA node with
  DMA and DMA32 zones (found in /proc/zoneinfo), could not be started due to
  failed KVM initialization. With this update, libvirt sets the cpuset.mems
  parameter after the initialization, and domains with any nodeset (in
  /numatune/memory) can be started without an error. (BZ#1135871)

All libvirt users are advised to upgrade to these updated packages, which
contain backported patches to correct these issues. After installing the
updated packages, libvirtd will be restarted automatically.