USN-3035-3: Linux kernel (Wily HWE) vulnerability

14 July 2016

linux-lts-wily vulnerability

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

  • Ubuntu 14.04 LTS

Summary

The system could be made to crash under certain conditions.

Software Description

  • linux-lts-wily - Linux hardware enablement kernel from Wily for Trusty

Details

USN-3035-1 fixed vulnerabilities in the Linux kernel for Ubuntu 15.10. This update provides the corresponding updates for the Linux Hardware Enablement (HWE) kernel from Ubuntu 15.10 for Ubuntu 14.04 LTS.

Jan Stancek discovered that the Linux kernel’s memory manager did not properly handle moving pages mapped by the asynchronous I/O (AIO) ring buffer to the other nodes. 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 versions:

Ubuntu 14.04 LTS
linux-image-4.2.0-42-generic - 4.2.0-42.49~14.04.1
linux-image-4.2.0-42-generic-lpae - 4.2.0-42.49~14.04.1
linux-image-4.2.0-42-lowlatency - 4.2.0-42.49~14.04.1
linux-image-4.2.0-42-powerpc-e500mc - 4.2.0-42.49~14.04.1
linux-image-4.2.0-42-powerpc-smp - 4.2.0-42.49~14.04.1
linux-image-4.2.0-42-powerpc64-emb - 4.2.0-42.49~14.04.1
linux-image-4.2.0-42-powerpc64-smp - 4.2.0-42.49~14.04.1

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.

References