[Ksplice][Ubuntu-20.04-Updates] New Ksplice updates for Ubuntu 20.04 Focal (USN-4917-1)

[Oracle Ksplice]

Synopsis: USN-4917-1 can now be patched using Ksplice
CVEs: CVE-2021-29154 CVE-2021-3492 CVE-2021-3493

Systems running Ubuntu 20.04 Focal can now use Ksplice to patch
against the latest Ubuntu Security Notice, USN-4917-1.

INSTALLING THE UPDATES

We recommend that all users of Ksplice Uptrack running Ubuntu 20.04
Focal 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

* CVE-2021-3492: Code execution in ioctls of ShiftFS file system.

Bad error handling in ioctls of the shiftfs file system could lead to
memory leaks and incorrect return codes from ioctl calls. A local
attacker could use this flaw to cause a denial-of-service by memory
exhaustion or execute arbitrary code.


* CVE-2021-29154: Code execution in eBPF JIT compiler.

Improper computation validation of branch displacements in eBPF JIT
compiler could lead to memory corruption. A local attacker with
the ability to insert eBPF instructions could use this flaw to cause
a denial-of-service or possibly execute arbitrary code.


* CVE-2021-3493: Elevation of privileges in overlayfs file system.

A flaw in overlayfs file system implementation could result in failure
to properly validate the application of file system capabilities with
respect to user namespaces. A local attacker could use this flaw to gain
elevated privileges.

SUPPORT

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