Ubuntu 19.04 and 18.04 LTS: USN-4209-1 Critical Kernel Issues

ubuntu

December 2, 2019

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 2

- linux-aws-5.0: Linux kernel for Amazon Web Services (AWS) systems

- linux-gke-5.0: Linux kernel for Google Container Engine (GKE) systems

- linux-hwe: Linux hardware enablement (HWE) kernel

- linux-oem-osp1: Linux kernel for OEM processors- linux-oracle-5.0: Linux kernel for Oracle Cloud systems

Details:

Jann Horn discovered that the OverlayFS and ShiftFS Drivers in the Linux

kernel did not properly handle reference counting during memory mapping

operations when used in conjunction with AUFS. A local attacker could use

this to cause a denial of service (system crash) or possibly execute

arbitrary code. ...

Read the Full Advisory

Topics Covered

security advisory denial of service buffer overflow Ubuntu memory leak kernel system crash

Update Instructions

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

Ubuntu 19.04:
  linux-image-5.0.0-1008-oracle   5.0.0-1008.13
  linux-image-5.0.0-1022-aws      5.0.0-1022.25
  linux-image-5.0.0-1023-kvm      5.0.0-1023.25
  linux-image-5.0.0-1023-raspi2   5.0.0-1023.24
  linux-image-5.0.0-1026-gcp      5.0.0-1026.27
  linux-image-5.0.0-37-generic    5.0.0-37.40
  linux-image-5.0.0-37-generic-lpae  5.0.0-37.40
  linux-image-5.0.0-37-lowlatency  5.0.0-37.40
  linux-image-aws                 5.0.0.1022.24
  linux-image-gcp                 5.0.0.1026.51
  linux-image-generic             5.0.0.37.39
  linux-image-generic-lpae        5.0.0.37.39
  linux-image-gke                 5.0.0.1026.51
  linux-image-kvm                 5.0.0.1023.24
  linux-image-lowlatency          5.0.0.37.39
  linux-image-oracle              5.0.0.1008.34
  linux-image-raspi2              5.0.0.1023.21
  linux-image-virtual             5.0.0.37.39

Ubuntu 18.04 LTS:
  linux-image-5.0.0-1008-oracle   5.0.0-1008.13~18.04.1
  linux-image-5.0.0-1022-aws      5.0.0-1022.25~18.04.1
  linux-image-5.0.0-1026-gcp      5.0.0-1026.27~18.04.1
  linux-image-5.0.0-1026-gke      5.0.0-1026.27~18.04.2
  linux-image-5.0.0-1030-oem-osp1  5.0.0-1030.34
  linux-image-5.0.0-37-generic    5.0.0-37.40~18.04.1
  linux-image-5.0.0-37-generic-lpae  5.0.0-37.40~18.04.1
  linux-image-5.0.0-37-lowlatency  5.0.0-37.40~18.04.1
  linux-image-aws-edge            5.0.0.1022.36
  linux-image-gcp                 5.0.0.1026.30
  linux-image-generic-hwe-18.04   5.0.0.37.95
  linux-image-generic-lpae-hwe-18.04  5.0.0.37.95
  linux-image-gke-5.0             5.0.0.1026.15
  linux-image-lowlatency-hwe-18.04  5.0.0.37.95
  linux-image-oem-osp1            5.0.0.1030.34
  linux-image-oracle-edge         5.0.0.1008.7
  linux-image-snapdragon-hwe-18.04  5.0.0.37.95
  linux-image-virtual-hwe-18.04   5.0.0.37.95

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.