4.9 - USN-2463-1

A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 12.04 LTS

Summary:

Several security issues were fixed in the kernel.

Software Description: - linux: Linux kernel

Details:

A race condition with MMIO and PIO transactions in the KVM (Kernel Virtual Machine) subsystem of the Linux kernel was discovered. A guest OS user could exploit this flaw to cause a denial of service (guest OS crash) via a specially crafted application. (CVE-2014-7842)

The KVM (kernel virtual machine) subsystem of the Linux kernel miscalculates the number of memory pages during the handling of a mapping failure. A guest OS user could exploit this to cause a denial of service (host OS page unpinning) or possibly have unspecified other impact by leveraging guest OS privileges. (CVE-2014-8369)

Update instructions:

The problem can be corrected by updating your system to the following package versions:

Ubuntu 12.04 LTS:
linux-image-3.2.0-75-generic 3.2.0-75.110
linux-image-3.2.0-75-generic-pae 3.2.0-75.110
linux-image-3.2.0-75-highbank 3.2.0-75.110
linux-image-3.2.0-75-omap 3.2.0-75.110
linux-image-3.2.0-75-powerpc-smp 3.2.0-75.110
linux-image-3.2.0-75-powerpc64-smp 3.2.0-75.110
linux-image-3.2.0-75-virtual 3.2.0-75.110

After a standard system update you need to reboot your computer to make all the necessary changes.

ATTENTION: Due to an unavoidable ABI change the kernel updates have been given a new version number, which requires you to recompile and reinstall all third party kernel modules you might have installed. If you use linux-restricted-modules, you have to update that package as well to get modules which work with the new kernel version. Unless you manually uninstalled the standard kernel metapackages (e.g. linux-generic, linux-server, linux-powerpc), a standard system upgrade will automatically perform this as well.

References:
http://www.ubuntu.com/usn/usn-2463-1
CVE-2014-7842, CVE-2014-8369

Package Information:
https://launchpad.net/ubuntu/+source/linux/3.2.0-75.110