Date:         Tue, 2 Mar 2010 11:58:32 -0600
Reply-To:     Troy Dawson 
Sender:       Security Errata for Scientific Linux
              
From:         Troy Dawson 
Subject:      Security ERRATA Important: kvm on SL5.4 x86_64
Comments: To: "scientific-linux-errata@fnal.gov"
          

Synopsis:	Important: kvm security and bug fix update
Issue date:	2010-03-01
CVE Names:	CVE-2009-3722 CVE-2010-0419

CVE-2009-3722 KVM: Check cpl before emulating debug register access
CVE-2010-0419 kvm: emulator privilege escalation segment selector check

A flaw was found in the way the x86 emulator loaded segment selectors 
(used for memory segmentation and protection) into segment registers. In 
some guest system configurations, an unprivileged guest user could 
leverage this flaw to crash the guest or possibly escalate their 
privileges within the guest. (CVE-2010-0419)

The x86 emulator implementation was missing a check for the Current
Privilege Level (CPL) while accessing debug registers. An unprivileged
user in a guest could leverage this flaw to crash the guest.
(CVE-2009-3722)

This update also fixes the following bugs:

The return values of the bdrv_aio_write() and bdrv_aio_read() functions 
were ignored. If an immediate failure occurred in one of these 
functions, errors would be missed and the guest could hang or read 
corrupted data. (BZ#562776)

The following procedure must be performed before this update will take
effect:

1) Stop all KVM guest virtual machines.

2) Either reboot the hypervisor machine or, as the root user, remove 
(using "modprobe -r [module]") and reload (using "modprobe [module]") 
all of the following modules which are currently running (determined 
using "lsmod"): kvm, ksm, kvm-intel or kvm-amd.

3) Restart the KVM guest virtual machines.

SL 5.x

     SRPMS:
kvm-83-105.el5_4.27.src.rpm
     x86_64:
kmod-kvm-83-105.el5_4.27.x86_64.rpm
kvm-83-105.el5_4.27.x86_64.rpm
kvm-qemu-img-83-105.el5_4.27.x86_64.rpm
kvm-tools-83-105.el5_4.27.x86_64.rpm

-Connie Sieh
-Troy Dawson