(RHSA-2015:0869) Important: kvm security update

KVM (Kernel-based Virtual Machine) is a full virtualization solution for
Linux on AMD64 and Intel 64 systems. KVM is a Linux kernel module built for
the standard Red Hat Enterprise Linux kernel.

It was found that KVM’s Write to Model Specific Register (WRMSR)
instruction emulation would write non-canonical values passed in by the
guest to certain MSRs in the host’s context. A privileged guest user could
use this flaw to crash the host. (CVE-2014-3610)

A race condition flaw was found in the way the Linux kernel’s KVM subsystem
handled PIT (Programmable Interval Timer) emulation. A guest user who has
access to the PIT I/O ports could use this flaw to crash the host.
(CVE-2014-3611)

Red Hat would like to thank Lars Bull of Google and Nadav Amit for
reporting the CVE-2014-3610 issue, and Lars Bull of Google for reporting
the CVE-2014-3611 issue.

All kvm users are advised to upgrade to these updated packages, which
contain backported patches to correct these issues. Note: The procedure in
the Solution section must be performed before this update will take effect.