=========================================================================
Ubuntu Security Notice USN-3910-1
March 15, 2019

linux, linux-aws, 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-kvm: Linux kernel for cloud environments
- linux-raspi2: Linux kernel for Raspberry Pi 2
- linux-snapdragon: Linux kernel for Snapdragon processors

Details:

It was discovered that the f2fs filesystem implementation in the Linux
kernel did not handle the noflush_merge mount option correctly. An attacker
could use this to cause a denial of service (system crash).
(CVE-2017-18241)

It was discovered that the procfs filesystem did not properly handle
processes mapping some memory elements onto files. A local attacker could
use this to block utilities that examine the procfs filesystem to report
operating system state, such as ps(1). (CVE-2018-1120)

Hui Peng and Mathias Payer discovered that the Option USB High Speed driver
in the Linux kernel did not properly validate metadata received from the
device. A physically proximate attacker could use this to cause a denial of
service (system crash). (CVE-2018-19985)

It was discovered that multiple integer overflows existed in the hugetlbfs
implementation in the Linux kernel. A local attacker could use this to
cause a denial of service (system crash). (CVE-2018-7740)

Jann Horn discovered a race condition in the fork() system call in the
Linux kernel. A local attacker could use this to gain access to services
that cache authorizations. (CVE-2019-6133)

Update instructions:

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

Ubuntu 16.04 LTS:
  linux-image-4.4.0-1041-kvm      4.4.0-1041.47
  linux-image-4.4.0-1077-aws      4.4.0-1077.87
  linux-image-4.4.0-1104-raspi2   4.4.0-1104.112
  linux-image-4.4.0-1108-snapdragon  4.4.0-1108.113
  linux-image-4.4.0-143-generic   4.4.0-143.169
  linux-image-4.4.0-143-generic-lpae  4.4.0-143.169
  linux-image-4.4.0-143-lowlatency  4.4.0-143.169
  linux-image-4.4.0-143-powerpc-e500mc  4.4.0-143.169
  linux-image-4.4.0-143-powerpc-smp  4.4.0-143.169
  linux-image-4.4.0-143-powerpc64-emb  4.4.0-143.169
  linux-image-4.4.0-143-powerpc64-smp  4.4.0-143.169
  linux-image-aws                 4.4.0.1077.80
  linux-image-generic             4.4.0.143.151
  linux-image-generic-lpae        4.4.0.143.151
  linux-image-kvm                 4.4.0.1041.41
  linux-image-lowlatency          4.4.0.143.151
  linux-image-powerpc-e500mc      4.4.0.143.151
  linux-image-powerpc-smp         4.4.0.143.151
  linux-image-powerpc64-emb       4.4.0.143.151
  linux-image-powerpc64-smp       4.4.0.143.151
  linux-image-raspi2              4.4.0.1104.104
  linux-image-snapdragon          4.4.0.1108.100
  linux-image-virtual             4.4.0.143.151

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/usn/usn-3910-1
  CVE-2017-18241, CVE-2018-1120, CVE-2018-19985, CVE-2018-7740,
  CVE-2019-6133

Package Information:
  https://launchpad.net/ubuntu/+source/linux/4.4.0-143.169
  https://launchpad.net/ubuntu/+source/linux-aws/4.4.0-1077.87
  https://launchpad.net/ubuntu/+source/linux-kvm/4.4.0-1041.47
  https://launchpad.net/ubuntu/+source/linux-raspi2/4.4.0-1104.112
  https://launchpad.net/ubuntu/+source/linux-snapdragon/4.4.0-1108.113