==========================================================================
Ubuntu Security Notice USN-6095-1
May 22, 2023

linux-gcp, linux-hwe, linux-raspi2, linux-snapdragon vulnerabilities
==========================================================================

A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS (Available with Ubuntu Pro)

Summary:

Several security issues were fixed in the Linux kernel.

Software Description:
- linux-raspi2: Linux kernel for Raspberry Pi systems
- linux-snapdragon: Linux kernel for Qualcomm Snapdragon processors
- linux-gcp: Linux kernel for Google Cloud Platform (GCP) systems
- linux-hwe: Linux hardware enablement (HWE) kernel

Details:

Jordy Zomer and Alexandra Sandulescu discovered that the Linux kernel did
not properly implement speculative execution barriers in usercopy functions
in certain situations. A local attacker could use this to expose sensitive
information (kernel memory). (CVE-2023-0459)

Xingyuan Mo discovered that the x86 KVM implementation in the Linux kernel
did not properly initialize some data structures. A local attacker could
use this to expose sensitive information (kernel memory). (CVE-2023-1513)

It was discovered that a use-after-free vulnerability existed in the iSCSI
TCP implementation in the Linux kernel. A local attacker could possibly use
this to cause a denial of service (system crash). (CVE-2023-2162)

It was discovered that the NET/ROM protocol implementation in the Linux
kernel contained a race condition in some situations, leading to a use-
after-free vulnerability. A local attacker could use this to cause a denial
of service (system crash) or possibly execute arbitrary code.
(CVE-2023-32269)

Duoming Zhou discovered that a race condition existed in the infrared
receiver/transceiver driver in the Linux kernel, leading to a use-after-
free vulnerability. A privileged attacker could use this to cause a denial
of service (system crash) or possibly execute arbitrary code.
(CVE-2023-1118)

Update instructions:

The problem can be corrected by updating your system to the following
package versions:

Ubuntu 18.04 LTS:
   linux-image-4.15.0-1132-raspi2  4.15.0-1132.140
   linux-image-4.15.0-1150-snapdragon  4.15.0-1150.160
   linux-image-raspi2              4.15.0.1132.127
   linux-image-snapdragon          4.15.0.1150.149

Ubuntu 16.04 LTS (Available with Ubuntu Pro):
   linux-image-4.15.0-1150-gcp     4.15.0-1150.166~16.04.1
   linux-image-4.15.0-211-generic  4.15.0-211.222~16.04.1
   linux-image-4.15.0-211-lowlatency  4.15.0-211.222~16.04.1
   linux-image-gcp                 4.15.0.1150.140
   linux-image-generic-hwe-16.04   4.15.0.211.196
   linux-image-gke                 4.15.0.1150.140
   linux-image-lowlatency-hwe-16.04  4.15.0.211.196
   linux-image-oem                 4.15.0.211.196
   linux-image-virtual-hwe-16.04   4.15.0.211.196

After a standard system update you need to reboot your computer to make
all the necessary changes.

ATTENTION: Due to an unavoidable ABI change the kernel updates have
been given a new version number, which requires you to recompile and
reinstall all third party kernel modules you might have installed.
Unless you manually uninstalled the standard kernel metapackages
(e.g. linux-generic, linux-generic-lts-RELEASE, linux-virtual,
linux-powerpc), a standard system upgrade will automatically perform
this as well.

References:
   https://ubuntu.com/security/notices/USN-6095-1
   CVE-2023-0459, CVE-2023-1118, CVE-2023-1513, CVE-2023-2162,
   CVE-2023-32269

Package Information:
   https://launchpad.net/ubuntu/+source/linux-raspi2/4.15.0-1132.140
   https://launchpad.net/ubuntu/+source/linux-snapdragon/4.15.0-1150.160