USN-4342-1: Linux kernel vulnerabilities

30 April 2020

linux, linux-aws, linux-azure, linux-azure-5.3, linux-gcp, linux-gcp-5.3, linux-gke-5.3, linux-hwe, linux-kvm, linux-oracle, linux-oracle-5.3, linux-raspi2, linux-raspi2-5.3 vulnerabilities

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

  • Ubuntu 19.10
  • Ubuntu 18.04 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-kvm - Linux kernel for cloud environments
  • linux-oracle - Linux kernel for Oracle Cloud systems
  • linux-raspi2 - Linux kernel for Raspberry Pi 2
  • linux-azure-5.3 - Linux kernel for Microsoft Azure Cloud systems
  • linux-gcp-5.3 - Linux kernel for Google Cloud Platform (GCP) systems
  • linux-gke-5.3 - Linux kernel for Google Container Engine (GKE) systems
  • linux-hwe - Linux hardware enablement (HWE) kernel
  • linux-oracle-5.3 - Linux kernel for Oracle Cloud systems
  • linux-raspi2-5.3 - Linux kernel for Raspberry Pi 2

Details

Al Viro discovered that the Linux kernel for s390x systems did not properly perform page table upgrades for kernel sections that use secondary address mode. A local attacker could use this to cause a denial of service (system crash) or execute arbitrary code. (CVE-2020-11884)

It was discovered that the Intel Wi-Fi driver in the Linux kernel did not properly check for errors in some situations. A local attacker could possibly use this to cause a denial of service (system crash). (CVE-2019-16234)

Tristan Madani discovered that the block I/O tracing implementation in the Linux kernel contained a race condition. A local attacker could use this to cause a denial of service (system crash) or possibly expose sensitive information. (CVE-2019-19768)

It was discovered that the vhost net driver in the Linux kernel contained a stack buffer overflow. A local attacker with the ability to perform ioctl() calls on /dev/vhost-net could use this to cause a denial of service (system crash). (CVE-2020-10942)

It was discovered that the virtual terminal implementation in the Linux kernel contained a race condition. A local attacker could possibly use this to cause a denial of service (system crash) or expose sensitive information. (CVE-2020-8648)

Shijie Luo discovered that the ext4 file system implementation in the Linux kernel did not properly check for a too-large journal size. An attacker could use this to construct a malicious ext4 image that, when mounted, could cause a denial of service (soft lockup). (CVE-2020-8992)

Jordy Zomer discovered that the floppy driver in the Linux kernel did not properly check for errors in some situations. A local attacker could possibly use this to cause a denial of service (system crash) or possibly expose sensitive information. (CVE-2020-9383)

Update instructions

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

Ubuntu 19.10
linux-image-5.3.0-1016-kvm - 5.3.0-1016.17
linux-image-5.3.0-1016-oracle - 5.3.0-1016.18
linux-image-5.3.0-1017-aws - 5.3.0-1017.18
linux-image-5.3.0-1018-gcp - 5.3.0-1018.19
linux-image-5.3.0-1020-azure - 5.3.0-1020.21
linux-image-5.3.0-1023-raspi2 - 5.3.0-1023.25
linux-image-5.3.0-51-generic - 5.3.0-51.44
linux-image-5.3.0-51-generic-lpae - 5.3.0-51.44
linux-image-5.3.0-51-lowlatency - 5.3.0-51.44
linux-image-5.3.0-51-snapdragon - 5.3.0-51.44
linux-image-aws - 5.3.0.1017.19
linux-image-azure - 5.3.0.1020.39
linux-image-gcp - 5.3.0.1018.19
linux-image-generic - 5.3.0.51.42
linux-image-generic-lpae - 5.3.0.51.42
linux-image-gke - 5.3.0.1018.19
linux-image-kvm - 5.3.0.1016.18
linux-image-lowlatency - 5.3.0.51.42
linux-image-oracle - 5.3.0.1016.31
linux-image-raspi2 - 5.3.0.1023.20
linux-image-snapdragon - 5.3.0.51.42
linux-image-virtual - 5.3.0.51.42
Ubuntu 18.04 LTS
linux-image-5.3.0-1016-oracle - 5.3.0-1016.18~18.04.1
linux-image-5.3.0-1018-gcp - 5.3.0-1018.19~18.04.1
linux-image-5.3.0-1018-gke - 5.3.0-1018.19~18.04.1
linux-image-5.3.0-1020-azure - 5.3.0-1020.21~18.04.1
linux-image-5.3.0-1023-raspi2 - 5.3.0-1023.25~18.04.1
linux-image-5.3.0-51-generic - 5.3.0-51.44~18.04.2
linux-image-5.3.0-51-generic-lpae - 5.3.0-51.44~18.04.2
linux-image-5.3.0-51-lowlatency - 5.3.0-51.44~18.04.2
linux-image-azure - 5.3.0.1020.20
linux-image-gcp - 5.3.0.1018.17
linux-image-generic-hwe-18.04 - 5.3.0.51.104
linux-image-generic-lpae-hwe-18.04 - 5.3.0.51.104
linux-image-gke-5.3 - 5.3.0.1018.8
linux-image-lowlatency-hwe-18.04 - 5.3.0.51.104
linux-image-oracle - 5.3.0.1016.17
linux-image-raspi2-hwe-18.04 - 5.3.0.1023.12
linux-image-snapdragon-hwe-18.04 - 5.3.0.51.104
linux-image-virtual-hwe-18.04 - 5.3.0.51.104

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

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