Scientific Linux Security Update : kvm on SL5.4 x86_64
High Nessus Plugin ID 60740
SynopsisThe remote Scientific Linux host is missing one or more security updates.
DescriptionCVE-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.
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.
SolutionUpdate the affected packages.