[USN-5114-1] Linux kernel vulnerabilities

========================================================================== Ubuntu Security Notice USN-5114-1 October 20, 2021
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-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
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-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-azure: Linux kernel for Microsoft Azure Cloud systems – linux-gcp: Linux kernel for Google Cloud Platform (GCP) systems – linux-hwe: Linux hardware enablement (HWE) kernel
It was discovered that a race condition existed in the Atheros Ath9k WiFi driver in the Linux kernel. An attacker could possibly use this to expose sensitive information (WiFi network traffic). (CVE-2020-3702)
It was discovered that the KVM hypervisor implementation in the Linux kernel did not properly compute the access permissions for shadow pages in some situations. A local attacker could use this to cause a denial of service. (CVE-2021-38198)
It was discovered that the ext4 file system in the Linux kernel contained a race condition when writing xattrs to an inode. A local attacker could use this to cause a denial of service or possibly gain administrative privileges. (CVE-2021-40490)
It was discovered that the 6pack network protocol driver in the Linux kernel did not properly perform validation checks. A privileged attacker could use this to cause a denial of service (system crash) or execute arbitrary code. (CVE-2021-42008)
Update instructions:
The problem can be corrected by updating your system to the following package versions:
Ubuntu 18.04 LTS: linux-image-4.15.0-1029-dell300x 4.15.0-1029.34 linux-image-4.15.0-1097-raspi2 4.15.0-1097.103 linux-image-4.15.0-1101-kvm 4.15.0-1101.103 linux-image-4.15.0-1110-gcp 4.15.0-1110.124 linux-image-4.15.0-1114-aws 4.15.0-1114.121 linux-image-4.15.0-1114-snapdragon 4.15.0-1114.123 linux-image-4.15.0-1125-azure 4.15.0-1125.138 linux-image-4.15.0-161-generic 4.15.0-161.169 linux-image-4.15.0-161-generic-lpae 4.15.0-161.169 linux-image-4.15.0-161-lowlatency 4.15.0-161.169 linux-image-aws-lts-18.04 linux-image-azure-lts-18.04 linux-image-dell300x linux-image-gcp-lts-18.04 linux-image-generic linux-image-generic-lpae linux-image-kvm linux-image-lowlatency linux-image-raspi2 linux-image-snapdragon linux-image-virtual
Ubuntu 16.04 ESM: linux-image-4.15.0-1110-gcp 4.15.0-1110.124~16.04.1 linux-image-4.15.0-1113-aws 4.15.0-1113.120~16.04.1 linux-image-4.15.0-1125-azure 4.15.0-1125.138~16.04.1 linux-image-4.15.0-161-generic 4.15.0-161.169~16.04.1 linux-image-4.15.0-161-lowlatency 4.15.0-161.169~16.04.1 linux-image-aws-hwe linux-image-azure linux-image-gcp linux-image-generic-hwe-16.04 linux-image-gke linux-image-lowlatency-hwe-16.04 linux-image-oem linux-image-virtual-hwe-16.04
Ubuntu 14.04 ESM: linux-image-4.15.0-1125-azure 4.15.0-1125.138~14.04.1 linux-image-azure
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: ubuntu.com/security/notices/USN-5114-1 CVE-2020-3702, CVE-2021-38198, CVE-2021-40490, CVE-2021-42008
Package Information: launchpad.net/ubuntu/+source/linux/4.15.0-161.169 launchpad.net/ubuntu/+source/linux-aws/4.15.0-1114.121 launchpad.net/ubuntu/+source/linux-azure-4.15/4.15.0-1125.138 launchpad.net/ubuntu/+source/linux-dell300x/4.15.0-1029.34 launchpad.net/ubuntu/+source/linux-gcp-4.15/4.15.0-1110.124 launchpad.net/ubuntu/+source/linux-kvm/4.15.0-1101.103 launchpad.net/ubuntu/+source/linux-raspi2/4.15.0-1097.103 launchpad.net/ubuntu/+source/linux-snapdragon/4.15.0-1114.123