(RHSA-2015:0868) Important: qemu-kvm-rhev security and bug fix update

KVM (Kernel-based Virtual Machine) is a full virtualization solution for
Linux on AMD64 and Intel 64 systems. The qemu-kvm-rhev package provides the
user-space component for running virtual machines using KVM in environments
managed by Red Hat Enterprise Virtualization Manager.

It was found that the Cirrus blit region checks were insufficient. A
privileged guest user could use this flaw to write outside of
VRAM-allocated buffer boundaries in the host’s QEMU process address space
with attacker-provided data. (CVE-2014-8106)

This issue was discovered by Paolo Bonzini of Red Hat.

This update also fixes the following bug:

• Previously, the effective downtime during the last phase of a live
  migration would sometimes be much higher than the maximum downtime
  specified by ‘migration_downtime’ in vdsm.conf. This problem has been
  corrected. The value of ‘migration_downtime’ is now honored and the
  migration is aborted if the downtime cannot be achieved. (BZ#1142756)

All users of qemu-kvm-rhev are advised to upgrade to these updated
packages, which contain a backported patch to correct this issue. After
installing this update, shut down all running virtual machines. Once all
virtual machines have shut down, start them again for this update to take
effect.