==========================================================================
Ubuntu Security Notice USN-5790-1
January 06, 2023

linux, linux-aws, linux-aws-hwe, linux-azure, linux-azure-4.15,
linux-dell300x, linux-gcp, linux-gcp-4.15, linux-hwe, linux-kvm,
linux-oracle, linux-raspi2, linux-snapdragon vulnerabilities
==========================================================================

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

- Ubuntu 18.04 LTS
- Ubuntu 16.04 ESM
- Ubuntu 14.04 ESM

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-4.15: Linux kernel for Microsoft Azure Cloud systems
- linux-dell300x: Linux kernel for Dell 300x platforms
- linux-gcp-4.15: Linux kernel for Google Cloud Platform (GCP) systems
- linux-kvm: Linux kernel for cloud environments
- linux-oracle: Linux kernel for Oracle Cloud systems
- linux-raspi2: Linux kernel for Raspberry Pi systems
- linux-snapdragon: Linux kernel for Qualcomm Snapdragon processors
- linux-aws-hwe: Linux kernel for Amazon Web Services (AWS-HWE) systems
- linux-gcp: Linux kernel for Google Cloud Platform (GCP) systems
- linux-hwe: Linux hardware enablement (HWE) kernel
- linux-azure: Linux kernel for Microsoft Azure Cloud systems

Details:

It was discovered that the BPF verifier in the Linux kernel did not
properly handle internal data structures. A local attacker could use this
to expose sensitive information (kernel memory). (CVE-2021-4159)

It was discovered that a race condition existed in the Android Binder IPC
subsystem in 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-2022-20421)

It was discovered that the Intel 740 frame buffer driver in the Linux
kernel contained a divide by zero vulnerability. A local attacker could use
this to cause a denial of service (system crash). (CVE-2022-3061)

Gwnaun Jung discovered that the SFB packet scheduling implementation in the
Linux kernel contained 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-2022-3586)

Jann Horn discovered a race condition existed in the Linux kernel when
unmapping VMAs in certain situations, resulting in possible use-after-free
vulnerabilities. A local attacker could possibly use this to cause a denial
of service (system crash) or execute arbitrary code. (CVE-2022-39188)

It was discovered that a race condition existed in the EFI capsule loader
driver in 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-2022-40307)

Zheng Wang and Zhuorao Yang discovered that the RealTek RTL8712U wireless
driver in the Linux kernel contained 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-2022-4095)

Update instructions:

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

Ubuntu 18.04 LTS:
   linux-image-4.15.0-1058-dell300x  4.15.0-1058.63
   linux-image-4.15.0-1112-oracle  4.15.0-1112.123
   linux-image-4.15.0-1125-raspi2  4.15.0-1125.133
   linux-image-4.15.0-1133-kvm     4.15.0-1133.138
   linux-image-4.15.0-1142-gcp     4.15.0-1142.158
   linux-image-4.15.0-1143-snapdragon  4.15.0-1143.153
   linux-image-4.15.0-1147-aws     4.15.0-1147.159
   linux-image-4.15.0-1158-azure   4.15.0-1158.173
   linux-image-4.15.0-201-generic  4.15.0-201.212
   linux-image-4.15.0-201-generic-lpae  4.15.0-201.212
   linux-image-4.15.0-201-lowlatency  4.15.0-201.212
   linux-image-aws-lts-18.04       4.15.0.1147.145
   linux-image-azure-lts-18.04     4.15.0.1158.126
   linux-image-dell300x            4.15.0.1058.57
   linux-image-gcp-lts-18.04       4.15.0.1142.156
   linux-image-generic             4.15.0.201.184
   linux-image-generic-lpae        4.15.0.201.184
   linux-image-kvm                 4.15.0.1133.124
   linux-image-lowlatency          4.15.0.201.184
   linux-image-oracle-lts-18.04    4.15.0.1112.117
   linux-image-raspi2              4.15.0.1125.120
   linux-image-snapdragon          4.15.0.1143.142
   linux-image-virtual             4.15.0.201.184

Ubuntu 16.04 ESM:
   linux-image-4.15.0-1112-oracle  4.15.0-1112.123~16.04.1
   linux-image-4.15.0-1142-gcp     4.15.0-1142.158~16.04.1
   linux-image-4.15.0-1147-aws-hwe  4.15.0-1147.159~16.04.1
   linux-image-4.15.0-201-generic  4.15.0-201.212~16.04.1
   linux-image-4.15.0-201-lowlatency  4.15.0-201.212~16.04.1
   linux-image-aws-hwe             4.15.0.1147.132
   linux-image-gcp                 4.15.0.1142.134
   linux-image-generic-hwe-16.04   4.15.0.201.186
   linux-image-gke                 4.15.0.1142.134
   linux-image-lowlatency-hwe-16.04  4.15.0.201.186
   linux-image-oem                 4.15.0.201.186
   linux-image-oracle              4.15.0.1112.94
   linux-image-virtual-hwe-16.04   4.15.0.201.186

Ubuntu 14.04 ESM:
   linux-image-4.15.0-1158-azure   4.15.0-1158.173~14.04.1
   linux-image-azure               4.15.0.1158.125

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-5790-1
   CVE-2021-4159, CVE-2022-20421, CVE-2022-3061, CVE-2022-3586,
   CVE-2022-39188, CVE-2022-40307, CVE-2022-4095

Package Information:
   https://launchpad.net/ubuntu/+source/linux/4.15.0-201.212
   https://launchpad.net/ubuntu/+source/linux-aws/4.15.0-1147.159
   https://launchpad.net/ubuntu/+source/linux-azure-4.15/4.15.0-1158.173
   https://launchpad.net/ubuntu/+source/linux-dell300x/4.15.0-1058.63
   https://launchpad.net/ubuntu/+source/linux-gcp-4.15/4.15.0-1142.158
   https://launchpad.net/ubuntu/+source/linux-kvm/4.15.0-1133.138
   https://launchpad.net/ubuntu/+source/linux-oracle/4.15.0-1112.123
   https://launchpad.net/ubuntu/+source/linux-raspi2/4.15.0-1125.133
   https://launchpad.net/ubuntu/+source/linux-snapdragon/4.15.0-1143.153