RHEA-2018:1934 - Product Enhancement Advisory

Topic

Updated microcode_ctl packages that fix one bug and add one enhancement are now available for Red Hat Enterprise Linux 6.

Description

The microcode_ctl packages provide microcode updates for Intel and AMD processors.

This update fixes the following bug:

• A previous update to the microcode_ctl packages that added new capabilities to enhance mitigation of CVE-2017-5715 (the Spectre variant 2 vulnerability) introduced a regression when it inadvertently removed support for AMD CPUID 0x00610f01. As a consequence, the kernel would be unable to update the microcode loaded by BIOS or UEFI if it was outdated because the loaded microcode version is dependent on the BIOS or UEFI version in use. This update restores microcode support for the mentioned CPU family, and the microcode can be correctly updated again. (BZ#1584192)

In addition, this update adds the following enhancement:

• The Intel CPU microcode has been updated to the latest upstream version, which also provides new capabilities used by the Linux kernel to mitigate CVE-2018-3639, known as the Speculative Store Bypass vulnerability. (BZ#1573451)

Users of microcode_ctl are advised to upgrade to these updated packages, which fix this bug and add this enhancement.

Solution

For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

Note: a system reboot is necessary for this update to take effect.

Affected Products

• Red Hat Enterprise Linux Server 6 x86_64
• Red Hat Enterprise Linux Server 6 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 i386
• Red Hat Enterprise Linux Workstation 6 x86_64
• Red Hat Enterprise Linux Workstation 6 i386
• Red Hat Enterprise Linux Desktop 6 x86_64
• Red Hat Enterprise Linux Desktop 6 i386
• Red Hat Enterprise Linux for Scientific Computing 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support Extension 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support Extension 6 i386

Fixes

• BZ - 1584192 - include AMD CPUID 0x00610f01 in RHEL-6 microcode_ctl

CVEs

(none)

References

• https://access.redhat.com/security/vulnerabilities/ssbd