==========================================================================
Ubuntu Security Notice USN-3444-1
October 10, 2017

linux, linux-aws, linux-gke, linux-kvm, linux-raspi2, linux-snapdragon vulnerabilities
==========================================================================

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

- Ubuntu 16.04 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-gke: Linux kernel for Google Container Engine (GKE) systems
- linux-kvm: Linux kernel for cloud environments
- linux-raspi2: Linux kernel for Raspberry Pi 2
- linux-snapdragon: Linux kernel for Snapdragon processors

Details:

Jan H. Schonherr discovered that the Xen subsystem did not properly handle
block IO merges correctly in some situations. An attacker in a guest vm
could use this to cause a denial of service (host crash) or possibly gain
administrative privileges in the host. (CVE-2017-12134)

Andrey Konovalov discovered that a divide-by-zero error existed in the TCP
stack implementation in the Linux kernel. A local attacker could use this
to cause a denial of service (system crash). (CVE-2017-14106)

Otto Ebeling discovered that the memory manager in the Linux kernel did not
properly check the effective UID in some situations. A local attacker could
use this to expose sensitive information. (CVE-2017-14140)

Update instructions:

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

Ubuntu 16.04 LTS:
  linux-image-4.4.0-1008-kvm      4.4.0-1008.13
  linux-image-4.4.0-1032-gke      4.4.0-1032.32
  linux-image-4.4.0-1038-aws      4.4.0-1038.47
  linux-image-4.4.0-1075-raspi2   4.4.0-1075.83
  linux-image-4.4.0-1077-snapdragon  4.4.0-1077.82
  linux-image-4.4.0-97-generic    4.4.0-97.120
  linux-image-4.4.0-97-generic-lpae  4.4.0-97.120
  linux-image-4.4.0-97-lowlatency  4.4.0-97.120
  linux-image-4.4.0-97-powerpc-e500mc  4.4.0-97.120
  linux-image-4.4.0-97-powerpc-smp  4.4.0-97.120
  linux-image-4.4.0-97-powerpc64-emb  4.4.0-97.120
  linux-image-4.4.0-97-powerpc64-smp  4.4.0-97.120
  linux-image-aws                 4.4.0.1038.40
  linux-image-generic             4.4.0.97.102
  linux-image-generic-lpae        4.4.0.97.102
  linux-image-gke                 4.4.0.1032.33
  linux-image-kvm                 4.4.0.1008.8
  linux-image-lowlatency          4.4.0.97.102
  linux-image-powerpc-e500mc      4.4.0.97.102
  linux-image-powerpc-smp         4.4.0.97.102
  linux-image-powerpc64-emb       4.4.0.97.102
  linux-image-powerpc64-smp       4.4.0.97.102
  linux-image-raspi2              4.4.0.1075.75
  linux-image-snapdragon          4.4.0.1077.69

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://www.ubuntu.com/usn/usn-3444-1
  CVE-2017-12134, CVE-2017-14106, CVE-2017-14140

Package Information:
  https://launchpad.net/ubuntu/+source/linux/4.4.0-97.120
  https://launchpad.net/ubuntu/+source/linux-aws/4.4.0-1038.47
  https://launchpad.net/ubuntu/+source/linux-gke/4.4.0-1032.32
  https://launchpad.net/ubuntu/+source/linux-kvm/4.4.0-1008.13
  https://launchpad.net/ubuntu/+source/linux-raspi2/4.4.0-1075.83
  https://launchpad.net/ubuntu/+source/linux-snapdragon/4.4.0-1077.82