USN-3522-3: Linux kernel regression

Ubuntu Security Notice USN-3522-3

10th January, 2018

linux regression

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

  • Ubuntu 16.04 LTS

Summary

USN-3522-1 introduced a regression in the Linux kernel.

Software description

  • linux - Linux kernel

Details

USN-3522-1 fixed a vulnerability in the Linux kernel to address
Meltdown (CVE-2017-5754). Unfortunately, that update introduced
a regression where a few systems failed to boot successfully. This
update fixes the problem.

We apologize for the inconvenience.

Original advisory details:

Jann Horn discovered that microprocessors utilizing speculative execution
and indirect branch prediction may allow unauthorized memory reads via
sidechannel attacks. This flaw is known as Meltdown. A local attacker could
use this to expose sensitive information, including kernel memory.

Update instructions

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

Ubuntu 16.04 LTS:
linux-image-generic 4.4.0.109.114
linux-image-4.4.0-109-lowlatency 4.4.0-109.132
linux-image-lowlatency 4.4.0.109.114
linux-image-4.4.0-109-generic 4.4.0-109.132

To update your system, please follow these instructions: http://ift.tt/17VXqjU.

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

LP: 1741934



from Ubuntu Security Notices http://ift.tt/2qRa8Sf