(RHSA-2011:0534) Important: qemu-kvm security, bug fix, and enhancement update

KVM (Kernel-based Virtual Machine) is a full virtualization solution for
Linux on AMD64 and Intel 64 systems. qemu-kvm is the user-space component
for running virtual machines using KVM.

It was found that the virtio-blk driver in qemu-kvm did not properly
validate read and write requests from guests. A privileged guest user could
use this flaw to crash the guest or, possibly, execute arbitrary code on
the host. (CVE-2011-1750)

It was found that the PIIX4 Power Management emulation layer in qemu-kvm
did not properly check for hot plug eligibility during device removals. A
privileged guest user could use this flaw to crash the guest or, possibly,
execute arbitrary code on the host. (CVE-2011-1751)

Red Hat would like to thank Nelson Elhage for reporting CVE-2011-1751.

This update also fixes several bugs and adds various enhancements.
Documentation for these bug fixes and enhancements will be available
shortly from the Technical Notes document, linked to in the References
section.

All users of qemu-kvm should upgrade to these updated packages, which
contain backported patches to resolve these issues, and fix the bugs and
add the enhancements noted in the Technical Notes. 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.