A Linux kernel security update has been released for Ubuntu Linux 20.04 LTS and 22.04 LTS.

USN-5667-1: Linux kernel vulnerabilities

==========================================================================
Ubuntu Security Notice USN-5667-1
October 10, 2022

linux, linux-aws, linux-aws-5.15, linux-azure, linux-azure-5.15,
linux-gcp, linux-gke, linux-gkeop, linux-hwe-5.15, linux-kvm,
linux-lowlatency, linux-lowlatency-hwe-5.15, linux-oracle, linux-raspi
vulnerabilities
==========================================================================

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

- Ubuntu 22.04 LTS
- Ubuntu 20.04 LTS

Summary:

Several security issues were fixed in the Linux kernel.

Software Description:
- linux: Linux kernel
- linux-aws: Linux kernel for Amazon Web Services (AWS) systems
- linux-azure: Linux kernel for Microsoft Azure Cloud systems
- linux-gcp: Linux kernel for Google Cloud Platform (GCP) systems
- linux-gke: Linux kernel for Google Container Engine (GKE) systems
- linux-gkeop: Linux kernel for Google Container Engine (GKE) systems
- linux-kvm: Linux kernel for cloud environments
- linux-lowlatency: Linux low latency kernel
- linux-oracle: Linux kernel for Oracle Cloud systems
- linux-raspi: Linux kernel for Raspberry Pi systems
- linux-aws-5.15: Linux kernel for Amazon Web Services (AWS) systems
- linux-azure-5.15: Linux kernel for Microsoft Azure cloud systems
- linux-hwe-5.15: Linux hardware enablement (HWE) kernel
- linux-lowlatency-hwe-5.15: Linux low latency kernel

Details:

Selim Enes Karaduman discovered that a race condition existed in the
General notification queue implementation of the Linux kernel, 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-2022-1882)

Pawan Kumar Gupta, Alyssa Milburn, Amit Peled, Shani Rehana, Nir Shildan
and Ariel Sabba discovered that some Intel processors with Enhanced
Indirect Branch Restricted Speculation (eIBRS) did not properly handle RET
instructions after a VM exits. A local attacker could potentially use this
to expose sensitive information. (CVE-2022-26373)

Eric Biggers discovered that a use-after-free vulnerability existed in the
io_uring subsystem in the Linux kernel. A local attacker could possibly use
this to cause a denial of service (system crash) or possibly execute
arbitrary code. (CVE-2022-3176)

It was discovered that the Netlink Transformation (XFRM) subsystem in the
Linux kernel contained a reference counting error. A local attacker could
use this to cause a denial of service (system crash). (CVE-2022-36879)

Jann Horn discovered that the KVM subsystem in the Linux kernel did not
properly handle TLB flush operations in some situations. A local attacker
in a guest VM could use this to cause a denial of service (guest crash) or
possibly execute arbitrary code in the guest kernel. (CVE-2022-39189)

Update instructions:

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

Ubuntu 22.04 LTS:
linux-image-5.15.0-1004-gkeop 5.15.0-1004.6
linux-image-5.15.0-1016-raspi 5.15.0-1016.18
linux-image-5.15.0-1016-raspi-nolpae 5.15.0-1016.18
linux-image-5.15.0-1017-gke 5.15.0-1017.20
linux-image-5.15.0-1019-gcp 5.15.0-1019.25
linux-image-5.15.0-1019-kvm 5.15.0-1019.23
linux-image-5.15.0-1019-oracle 5.15.0-1019.24
linux-image-5.15.0-1021-aws 5.15.0-1021.25
linux-image-5.15.0-1021-azure 5.15.0-1021.26
linux-image-5.15.0-50-generic 5.15.0-50.56
linux-image-5.15.0-50-generic-64k 5.15.0-50.56
linux-image-5.15.0-50-generic-lpae 5.15.0-50.56
linux-image-5.15.0-50-lowlatency 5.15.0-50.56
linux-image-5.15.0-50-lowlatency-64k 5.15.0-50.56
linux-image-aws 5.15.0.1021.21
linux-image-aws-lts-22.04 5.15.0.1021.21
linux-image-azure 5.15.0.1021.20
linux-image-azure-lts-22.04 5.15.0.1021.20
linux-image-gcp 5.15.0.1019.17
linux-image-generic 5.15.0.50.50
linux-image-generic-64k 5.15.0.50.50
linux-image-generic-64k-hwe-22.04 5.15.0.50.50
linux-image-generic-hwe-22.04 5.15.0.50.50
linux-image-generic-lpae 5.15.0.50.50
linux-image-generic-lpae-hwe-22.04 5.15.0.50.50
linux-image-gke 5.15.0.1017.19
linux-image-gke-5.15 5.15.0.1017.19
linux-image-gkeop 5.15.0.1004.6
linux-image-gkeop-5.15 5.15.0.1004.6
linux-image-kvm 5.15.0.1019.17
linux-image-lowlatency 5.15.0.50.46
linux-image-lowlatency-64k 5.15.0.50.46
linux-image-lowlatency-64k-hwe-22.04 5.15.0.50.46
linux-image-lowlatency-hwe-22.04 5.15.0.50.46
linux-image-oracle 5.15.0.1019.17
linux-image-raspi 5.15.0.1016.15
linux-image-raspi-nolpae 5.15.0.1016.15
linux-image-virtual 5.15.0.50.50
linux-image-virtual-hwe-22.04 5.15.0.50.50

Ubuntu 20.04 LTS:
linux-image-5.15.0-1021-aws 5.15.0-1021.25~20.04.1
linux-image-5.15.0-1021-azure 5.15.0-1021.26~20.04.1
linux-image-5.15.0-50-generic 5.15.0-50.56~20.04.1
linux-image-5.15.0-50-generic-64k 5.15.0-50.56~20.04.1
linux-image-5.15.0-50-generic-lpae 5.15.0-50.56~20.04.1
linux-image-5.15.0-50-lowlatency 5.15.0-50.56~20.04.1
linux-image-5.15.0-50-lowlatency-64k 5.15.0-50.56~20.04.1
linux-image-aws 5.15.0.1021.25~20.04.13
linux-image-azure 5.15.0.1021.26~20.04.14
linux-image-generic-64k-hwe-20.04 5.15.0.50.56~20.04.19
linux-image-generic-hwe-20.04 5.15.0.50.56~20.04.19
linux-image-generic-lpae-hwe-20.04 5.15.0.50.56~20.04.19
linux-image-lowlatency-64k-hwe-20.04 5.15.0.50.56~20.04.17
linux-image-lowlatency-hwe-20.04 5.15.0.50.56~20.04.17
linux-image-virtual-hwe-20.04 5.15.0.50.56~20.04.19

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-5667-1
CVE-2022-1882, CVE-2022-26373, CVE-2022-3176, CVE-2022-36879,
CVE-2022-39189

Package Information:
https://launchpad.net/ubuntu/+source/linux/5.15.0-50.56
https://launchpad.net/ubuntu/+source/linux-aws/5.15.0-1021.25
https://launchpad.net/ubuntu/+source/linux-azure/5.15.0-1021.26
https://launchpad.net/ubuntu/+source/linux-gcp/5.15.0-1019.25
https://launchpad.net/ubuntu/+source/linux-gke/5.15.0-1017.20
https://launchpad.net/ubuntu/+source/linux-gkeop/5.15.0-1004.6
https://launchpad.net/ubuntu/+source/linux-kvm/5.15.0-1019.23
https://launchpad.net/ubuntu/+source/linux-lowlatency/5.15.0-50.56
https://launchpad.net/ubuntu/+source/linux-oracle/5.15.0-1019.24
https://launchpad.net/ubuntu/+source/linux-raspi/5.15.0-1016.18
https://launchpad.net/ubuntu/+source/linux-aws-5.15/5.15.0-1021.25~20.04.1
https://launchpad.net/ubuntu/+source/linux-azure-5.15/5.15.0-1021.26~20.04.1
https://launchpad.net/ubuntu/+source/linux-hwe-5.15/5.15.0-50.56~20.04.1

https://launchpad.net/ubuntu/+source/linux-lowlatency-hwe-5.15/5.15.0-50.56~20.04.1