[El-errata] New Ksplice updates for RHCK 6 (ELSA-2023-0187)

[Errata Announcements for Oracle Linux]

Synopsis: ELSA-2023-0187 can now be patched using Ksplice
CVEs: CVE-2021-26401

Users with Oracle Linux Premier Support can now use Ksplice to patch
against the latest Oracle Linux Security Advisory, ELSA-2023-0187.
More information about this errata can be found at
https://linux.oracle.com/errata/ELSA-2023-0187.html

INSTALLING THE UPDATES

We recommend that all users of Ksplice Uptrack running RHCK 6 install
these updates.

On systems that have "autoinstall = yes" in /etc/uptrack/uptrack.conf,
these updates will be installed automatically and you do not need to
take any action.

Alternatively, you can install these updates by running:

# /usr/sbin/uptrack-upgrade -y


DESCRIPTION

* Note: Oracle will not provide a zero downtime update for CVE-2021-26401.

On the 8th of March 2022, Vrije Universiteit (VU) Amsterdam
researchers, AMD, Ampere, ARM and Intel jointly reported new security
vulnerabilities based on Branch Target Injection (BTI) (commonly
called Spectre v2 variants).

The reporters recommend disabling unprivileged BPF to mitigate this
vulnerability as well as using generic retpoline even when eIBRS is
available on the platform or on special AMD/Hygon CPUs.

Unprivileged BPF can already be disabled at runtime by setting the
kernel.unprivileged_bpf_disabled sysctl.

If your CPU is affected and is not already using retpoline as the
Spectre V2 mitigation, a reboot into the newest kernel will be
required in order to get the full retpoline mitigations in place.

SUPPORT

Ksplice support is available at ksplice-support_ww at oracle.com.