Ubuntu Update for linux USN-1363-1

Summary
Ubuntu Update for Linux kernel vulnerabilities USN-1363-1
Solution
Please Install the Updated Packages.
Insight
A flaw was found in KVM's Programmable Interval Timer (PIT). When a virtual interrupt control is not available a local user could use this to cause a denial of service by starting a timer. (CVE-2011-4622) A flaw was discovered in the XFS filesystem. If a local user mounts a specially crafted XFS image it could potential execute arbitrary code on the system. (CVE-2012-0038) Andy Whitcroft discovered a that the Overlayfs filesystem was not doing the extended permission checks needed by cgroups and Linux Security Modules (LSMs). A local user could exploit this to by-pass security policy and access files that should not be accessible. (CVE-2012-0055) A flaw was found in the linux kernels IPv4 IGMP query processing. A remote attacker could exploit this to cause a denial of service. (CVE-2012-0207)
Affected
linux on Ubuntu 11.10