Canonical holds Ubuntu to the highest standards of security and quality. This week we published candidate Ubuntu kernels providing mitigation for CVE-2017-5715 and CVE-2017-5753 (ie, Spectre / Variants 1 & 2) to their respective -proposed pockets for Ubuntu 17.10 (Artful), 16.04 LTS (Xenial), and 14.04 LTS (Trusty). We have also expanded mitigation to cover s390x and ppc64el.
You are invited to test and provide feedback for the following updated Linux kernels. We have also rebased all derivative kernels such as the public cloud kernels (Amazon, Google, Microsoft, etc) and the Hardware Enablement (HWE) kernels.
- 17.10 (Artful): linux-4.13.0-30.33
- 16.04 LTS (Xenial): linux-4.4.0-111.134
- 14.04 LTS (Trusty): linux-3.13.0-140.189
- 17.04 is end-of-life and won’t be patched for either Meltdown or Spectre
Updates for Ubuntu 12.04 ESM are in progress, and will be available for Canonical’s Ubuntu Advantage customers. UA customers should reach out to Canonical support for access to candidate kernels.
We intend to promote the candidate kernels to the -security/-updates pocket for General Availability (GA) on Monday, January 22, 2018.
There is a corresponding intel-microcode update for many Intel CPUs, as well as an eventual amd64-microcode update, that will also need to be applied in order to fully mitigate Spectre. In the interest of full disclosure, we understand from Intel that there are currently known issues with the intel-microcode binary:
Canonical QA and Hardware Certification teams are engaged in extensive, automated and manual testing of these kernels and the Intel microcode kernel updates on Ubuntu certified hardware, and Ubuntu certified public clouds. The primary focus is on regression testing and security effectiveness. We are actively investigating Google’s “Retpoline” toolchain-based approach, which requires rebuilding Ubuntu binaries but reduce performance impact of the mitigation.
For your reference, the following links explain how to enable Ubuntu’s Proposed repositories, and how to file Linux kernel bugs:
The most current information will continue to be available at:
About the author
Dustin Kirkland is part of Canonical's Ubuntu Product and Strategy team, working for Mark Shuttleworth, and leading the technical strategy, road map, and life cycle of the Ubuntu Cloud and IoT commercial offerings.
Formerly the CTO of Gazzang, a venture funded start-up acquired by Cloudera, Dustin designed and implemented an innovative key management system for the cloud, called zTrustee, and delivered comprehensive security for cloud and big data platforms with eCryptfs and other encryption technologies.
Dustin is an active Core Developer of the Ubuntu Linux distribution, maintainer of 20+ open source projects, and the creator of Byobu, DivItUp.com, and LinuxSearch.org.
A Fightin' Texas Aggie Class of 2001 graduate, Dustin lives in Austin, Texas, with his wife Kim, daughters, and his Australian Shepherds, Aggie and Tiger. Dustin is also an avid home brewer.
More articles by Dustin