USN-2911-1: Linux kernel vulnerability

Ubuntu Security Notice USN-2911-1

22nd February, 2016

linux vulnerability

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

Ubuntu 12.04 LTS

Summary

The system could be made to crash under certain conditions.

Software description

linux
– Linux kernel

Details

It was discovered that the Linux kernel keyring subsystem contained a race
between read and revoke operations. A local attacker could use this to
cause a denial of service (system crash).

Update instructions

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

Ubuntu 12.04 LTS:: linux-image-3.2.0-99-generic-pae

3.2.0-99.139; linux-image-3.2.0-99-powerpc64-smp

3.2.0-99.139; linux-image-3.2.0-99-generic

3.2.0-99.139; linux-image-3.2.0-99-virtual

3.2.0-99.139; linux-image-3.2.0-99-highbank

3.2.0-99.139; linux-image-3.2.0-99-powerpc-smp

3.2.0-99.139; linux-image-3.2.0-99-omap

3.2.0-99.139

To update your system, please follow these instructions:
https://wiki.ubuntu.com/Security/Upgrades.

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.
Unless you manually uninstalled the standard kernel metapackages
(e.g. linux-generic, linux-generic-lts-RELEASE, linux-virtual,
linux-powerpc), a standard system upgrade will automatically perform
this as well.