=========================================================================
Ubuntu Security Notice USN-4135-2
September 18, 2019

linux, linux-aws, linux-azure, linux-lts-trusty, linux-lts-xenial
vulnerabilities
=========================================================================
A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 14.04 ESM
- Ubuntu 12.04 ESM

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-lts-xenial: Linux hardware enablement kernel from Xenial for Trusty
- linux-lts-trusty: Linux hardware enablement kernel from Trusty for Precise ESM

Details:

Peter Pi discovered a buffer overflow in the virtio network backend
(vhost_net) implementation in the Linux kernel. An attacker in a guest may
be able to use this to cause a denial of service (host OS crash) or
possibly execute arbitrary code in the host OS. (CVE-2019-14835)

It was discovered that the Linux kernel on PowerPC architectures did not
properly handle Facility Unavailable exceptions in some situations. A local
attacker could use this to expose sensitive information. (CVE-2019-15030)

It was discovered that the Linux kernel on PowerPC architectures did not
properly handle exceptions on interrupts in some situations. A local
attacker could use this to expose sensitive information. (CVE-2019-15031)

Update instructions:

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

Ubuntu 14.04 ESM:
  linux-image-3.13.0-173-generic  3.13.0-173.224
  linux-image-3.13.0-173-generic-lpae  3.13.0-173.224
  linux-image-3.13.0-173-lowlatency  3.13.0-173.224
  linux-image-3.13.0-173-powerpc-e500  3.13.0-173.224
  linux-image-3.13.0-173-powerpc-e500mc  3.13.0-173.224
  linux-image-3.13.0-173-powerpc-smp  3.13.0-173.224
  linux-image-3.13.0-173-powerpc64-emb  3.13.0-173.224
  linux-image-3.13.0-173-powerpc64-smp  3.13.0-173.224
  linux-image-4.15.0-1059-azure   4.15.0-1059.64~14.04.1
  linux-image-4.4.0-1054-aws      4.4.0-1054.58
  linux-image-4.4.0-164-generic   4.4.0-164.192~14.04.1
  linux-image-4.4.0-164-generic-lpae  4.4.0-164.192~14.04.1
  linux-image-4.4.0-164-lowlatency  4.4.0-164.192~14.04.1
  linux-image-4.4.0-164-powerpc-e500mc  4.4.0-164.192~14.04.1
  linux-image-4.4.0-164-powerpc-smp  4.4.0-164.192~14.04.1
  linux-image-4.4.0-164-powerpc64-emb  4.4.0-164.192~14.04.1
  linux-image-4.4.0-164-powerpc64-smp  4.4.0-164.192~14.04.1
  linux-image-aws                 4.4.0.1054.55
  linux-image-azure               4.15.0.1059.45
  linux-image-generic             3.13.0.173.184
  linux-image-generic-lpae        3.13.0.173.184
  linux-image-generic-lpae-lts-xenial  4.4.0.164.143
  linux-image-generic-lts-xenial  4.4.0.164.143
  linux-image-lowlatency          3.13.0.173.184
  linux-image-lowlatency-lts-xenial  4.4.0.164.143
  linux-image-powerpc-e500        3.13.0.173.184
  linux-image-powerpc-e500mc      3.13.0.173.184
  linux-image-powerpc-e500mc-lts-xenial  4.4.0.164.143
  linux-image-powerpc-smp         3.13.0.173.184
  linux-image-powerpc-smp-lts-xenial  4.4.0.164.143
  linux-image-powerpc64-emb       3.13.0.173.184
  linux-image-powerpc64-emb-lts-xenial  4.4.0.164.143
  linux-image-powerpc64-smp       3.13.0.173.184
  linux-image-powerpc64-smp-lts-xenial  4.4.0.164.143
  linux-image-server              3.13.0.173.184
  linux-image-virtual             3.13.0.173.184
  linux-image-virtual-lts-xenial  4.4.0.164.143

Ubuntu 12.04 ESM:
  linux-image-3.13.0-173-generic  3.13.0-173.224~12.04.1
  linux-image-3.13.0-173-generic-lpae  3.13.0-173.224~12.04.1
  linux-image-3.13.0-173-lowlatency  3.13.0-173.224~12.04.1
  linux-image-3.2.0-143-generic   3.2.0-143.190
  linux-image-3.2.0-143-generic-pae  3.2.0-143.190
  linux-image-3.2.0-143-highbank  3.2.0-143.190
  linux-image-3.2.0-143-omap      3.2.0-143.190
  linux-image-3.2.0-143-powerpc-smp  3.2.0-143.190
  linux-image-3.2.0-143-powerpc64-smp  3.2.0-143.190
  linux-image-3.2.0-143-virtual   3.2.0-143.190
  linux-image-generic             3.2.0.143.158
  linux-image-generic-lpae-lts-trusty  3.13.0.173.161
  linux-image-generic-lts-trusty  3.13.0.173.161
  linux-image-generic-pae         3.2.0.143.158
  linux-image-highbank            3.2.0.143.158
  linux-image-omap                3.2.0.143.158
  linux-image-powerpc             3.2.0.143.158
  linux-image-powerpc-smp         3.2.0.143.158
  linux-image-powerpc64-smp       3.2.0.143.158
  linux-image-server              3.2.0.143.158
  linux-image-virtual             3.2.0.143.158

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://usn.ubuntu.com/4135-2
  https://usn.ubuntu.com/4135-1
  CVE-2019-14835, CVE-2019-15030, CVE-2019-15031