RedHat: RHSA-2018-1642:01 Important: kernel-rt security update
Summary
The kernel-rt packages provide the Real Time Linux Kernel, which enables
fine-tuning for systems with extremely high determinism requirements.
Security Fix(es):
* An industry-wide issue was found in the way many modern microprocessor
designs have implemented speculative execution of Load & Store instructions
(a commonly used performance optimization). It relies on the presence of a
precisely-defined instruction sequence in the privileged code as well as
the fact that memory read from address to which a recent memory write has
occurred may see an older value and subsequently cause an update into the
microprocessor's data cache even for speculatively executed instructions
that never actually commit (retire). As a result, an unprivileged attacker
could use this flaw to read privileged memory by conducting targeted cache
side-channel attacks. (CVE-2018-3639)
Note: This issue is present in hardware and cannot be fully fixed via
software update. The updated kernel packages provide software side of the
mitigation for this hardware issue. To be fully functional, up-to-date CPU
microcode applied on the system is required. Please refer to References
section for further information about this issue, CPU microcode
requirements and the potential performance impact.
Red Hat would like to thank Ken Johnson (Microsoft Security Response
Center) and Jann Horn (Google Project Zero) for reporting this issue.
Summary
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
The system must be rebooted for this update to take effect.
References
https://access.redhat.com/security/cve/CVE-2018-3639 https://access.redhat.com/security/updates/classification/#important https://access.redhat.com/security/vulnerabilities/ssbd
Package List
Red Hat MRG Realtime for RHEL 6 Server v.2:
Source:
kernel-rt-3.10.0-693.25.7.rt56.615.el6rt.src.rpm
noarch:
kernel-rt-doc-3.10.0-693.25.7.rt56.615.el6rt.noarch.rpm
kernel-rt-firmware-3.10.0-693.25.7.rt56.615.el6rt.noarch.rpm
x86_64:
kernel-rt-3.10.0-693.25.7.rt56.615.el6rt.x86_64.rpm
kernel-rt-debug-3.10.0-693.25.7.rt56.615.el6rt.x86_64.rpm
kernel-rt-debug-debuginfo-3.10.0-693.25.7.rt56.615.el6rt.x86_64.rpm
kernel-rt-debug-devel-3.10.0-693.25.7.rt56.615.el6rt.x86_64.rpm
kernel-rt-debuginfo-3.10.0-693.25.7.rt56.615.el6rt.x86_64.rpm
kernel-rt-debuginfo-common-x86_64-3.10.0-693.25.7.rt56.615.el6rt.x86_64.rpm
kernel-rt-devel-3.10.0-693.25.7.rt56.615.el6rt.x86_64.rpm
kernel-rt-trace-3.10.0-693.25.7.rt56.615.el6rt.x86_64.rpm
kernel-rt-trace-debuginfo-3.10.0-693.25.7.rt56.615.el6rt.x86_64.rpm
kernel-rt-trace-devel-3.10.0-693.25.7.rt56.615.el6rt.x86_64.rpm
kernel-rt-vanilla-3.10.0-693.25.7.rt56.615.el6rt.x86_64.rpm
kernel-rt-vanilla-debuginfo-3.10.0-693.25.7.rt56.615.el6rt.x86_64.rpm
kernel-rt-vanilla-devel-3.10.0-693.25.7.rt56.615.el6rt.x86_64.rpm
These packages are GPG signed by Red Hat for security. Our key and
details on how to verify the signature are available from
https://access.redhat.com/security/team/key/
Topic
An update for kernel-rt is now available for Red Hat Enterprise MRG 2.Red Hat Product Security has rated this update as having a security impactof Important. A Common Vulnerability Scoring System (CVSS) base score,which gives a detailed severity rating, is available for each vulnerabilityfrom the CVE link(s) in the References section.
Topic
Relevant Releases Architectures
Red Hat MRG Realtime for RHEL 6 Server v.2 - noarch, x86_64
Bugs Fixed
1566890 - CVE-2018-3639 hw: cpu: speculative store bypass