Ubuntu 19.10 & 18.04 LTS: USN-4369-1 Critical Kernel Issues

ubuntu

May 20, 2020

Several security issues were fixed in the Linux kernel.

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-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 (V7) systems

- linux-aws-5.3: Linux kernel for Amazon Web Services (AWS) 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

Details:

It was discovered that the btrfs implementation in the Linux kernel did not

properly detect that a block was marked dirty in some situations. An

attacker could use this to specially craft a file system image that, when

unmounted, could cause a denial of service (system cr...

Read the Full Advisory

Topics Covered

security advisory denial of service Ubuntu kernel local attack information exposure system crash

Update Instructions

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

Ubuntu 19.10:
  linux-image-5.3.0-1017-kvm      5.3.0-1017.19
  linux-image-5.3.0-1018-oracle   5.3.0-1018.20
  linux-image-5.3.0-1019-aws      5.3.0-1019.21
  linux-image-5.3.0-1020-gcp      5.3.0-1020.22
  linux-image-5.3.0-1025-raspi2   5.3.0-1025.27
  linux-image-5.3.0-53-generic    5.3.0-53.47
  linux-image-5.3.0-53-generic-lpae  5.3.0-53.47
  linux-image-5.3.0-53-lowlatency  5.3.0-53.47
  linux-image-5.3.0-53-snapdragon  5.3.0-53.47
  linux-image-aws                 5.3.0.1019.31
  linux-image-gcp                 5.3.0.1020.31
  linux-image-generic             5.3.0.53.45
  linux-image-generic-lpae        5.3.0.53.45
  linux-image-gke                 5.3.0.1020.31
  linux-image-kvm                 5.3.0.1017.19
  linux-image-lowlatency          5.3.0.53.45
  linux-image-oracle              5.3.0.1018.33
  linux-image-raspi2              5.3.0.1025.22
  linux-image-snapdragon          5.3.0.53.45
  linux-image-virtual             5.3.0.53.45

Ubuntu 18.04 LTS:
  linux-image-5.3.0-1018-oracle   5.3.0-1018.20~18.04.1
  linux-image-5.3.0-1019-aws      5.3.0-1019.21~18.04.1
  linux-image-5.3.0-1020-gcp      5.3.0-1020.22~18.04.1
  linux-image-5.3.0-1020-gke      5.3.0-1020.22~18.04.1
  linux-image-5.3.0-53-generic    5.3.0-53.47~18.04.1
  linux-image-5.3.0-53-generic-lpae  5.3.0-53.47~18.04.1
  linux-image-5.3.0-53-lowlatency  5.3.0-53.47~18.04.1
  linux-image-aws                 5.3.0.1019.20
  linux-image-aws-edge            5.3.0.1019.20
  linux-image-gcp                 5.3.0.1020.19
  linux-image-gcp-edge            5.3.0.1020.19
  linux-image-generic-hwe-18.04   5.3.0.53.109
  linux-image-generic-lpae-hwe-18.04  5.3.0.53.109
  linux-image-gke-5.3             5.3.0.1020.10
  linux-image-gkeop-5.3           5.3.0.53.109
  linux-image-lowlatency-hwe-18.04  5.3.0.53.109
  linux-image-oracle              5.3.0.1018.19
  linux-image-snapdragon-hwe-18.04  5.3.0.53.109
  linux-image-virtual-hwe-18.04   5.3.0.53.109

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.