=========================================================================
Ubuntu Security Notice USN-4419-1
July 06, 2020

linux, linux-lts-xenial, linux-aws, linux-kvm, linux-raspi2,
linux-snapdragon vulnerabilities
=========================================================================
A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 16.04 LTS
- Ubuntu 14.04 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-kvm: Linux kernel for cloud environments
- linux-raspi2: Linux kernel for Raspberry Pi (V7) systems
- linux-snapdragon: Linux kernel for Qualcomm Snapdragon processors
- linux-lts-xenial: Linux hardware enablement kernel from Xenial for Trusty

Details:

It was discovered that a race condition existed in the Precision Time
Protocol (PTP) implementation in the Linux kernel, leading to a use-after-
free vulnerability. A local attacker could possibly use this to cause a
denial of service (system crash) or possibly execute arbitrary code.
(CVE-2020-10690)

Matthew Sheets discovered that the SELinux network label handling
implementation in the Linux kernel could be coerced into de-referencing a
NULL pointer. A remote attacker could use this to cause a denial of service
(system crash). (CVE-2020-10711)

It was discovered that the SCSI generic (sg) driver in the Linux kernel did
not properly handle certain error conditions correctly. A local privileged
attacker could use this to cause a denial of service (system crash).
(CVE-2020-12770)

It was discovered that the USB Gadget device driver in the Linux kernel did
not validate arguments passed from configfs in some situations. A local
attacker could possibly use this to cause a denial of service (system
crash) or possibly expose sensitive information. (CVE-2020-13143)

Shijie Luo discovered that the ext4 file system implementation in the Linux
kernel did not properly check for a too-large journal size. An attacker
could use this to construct a malicious ext4 image that, when mounted,
could cause a denial of service (soft lockup). (CVE-2020-8992)

Update instructions:

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

Ubuntu 16.04 LTS:
  linux-image-4.4.0-1076-kvm      4.4.0-1076.83
  linux-image-4.4.0-1110-aws      4.4.0-1110.121
  linux-image-4.4.0-1135-raspi2   4.4.0-1135.144
  linux-image-4.4.0-1139-snapdragon  4.4.0-1139.147
  linux-image-4.4.0-185-generic   4.4.0-185.215
  linux-image-4.4.0-185-generic-lpae  4.4.0-185.215
  linux-image-4.4.0-185-lowlatency  4.4.0-185.215
  linux-image-4.4.0-185-powerpc-e500mc  4.4.0-185.215
  linux-image-4.4.0-185-powerpc-smp  4.4.0-185.215
  linux-image-4.4.0-185-powerpc64-emb  4.4.0-185.215
  linux-image-4.4.0-185-powerpc64-smp  4.4.0-185.215
  linux-image-aws                 4.4.0.1110.114
  linux-image-generic             4.4.0.185.191
  linux-image-generic-lpae        4.4.0.185.191
  linux-image-kvm                 4.4.0.1076.74
  linux-image-lowlatency          4.4.0.185.191
  linux-image-powerpc-e500mc      4.4.0.185.191
  linux-image-powerpc-smp         4.4.0.185.191
  linux-image-powerpc64-emb       4.4.0.185.191
  linux-image-powerpc64-smp       4.4.0.185.191
  linux-image-raspi2              4.4.0.1135.135
  linux-image-snapdragon          4.4.0.1139.131
  linux-image-virtual             4.4.0.185.191

Ubuntu 14.04 ESM:
  linux-image-4.4.0-1074-aws      4.4.0-1074.78
  linux-image-4.4.0-185-generic   4.4.0-185.215~14.04.1
  linux-image-4.4.0-185-generic-lpae  4.4.0-185.215~14.04.1
  linux-image-4.4.0-185-lowlatency  4.4.0-185.215~14.04.1
  linux-image-4.4.0-185-powerpc-e500mc  4.4.0-185.215~14.04.1
  linux-image-4.4.0-185-powerpc-smp  4.4.0-185.215~14.04.1
  linux-image-4.4.0-185-powerpc64-emb  4.4.0-185.215~14.04.1
  linux-image-4.4.0-185-powerpc64-smp  4.4.0-185.215~14.04.1
  linux-image-aws                 4.4.0.1074.71
  linux-image-generic-lpae-lts-xenial  4.4.0.185.162
  linux-image-generic-lts-xenial  4.4.0.185.162
  linux-image-lowlatency-lts-xenial  4.4.0.185.162
  linux-image-powerpc-e500mc-lts-xenial  4.4.0.185.162
  linux-image-powerpc-smp-lts-xenial  4.4.0.185.162
  linux-image-powerpc64-emb-lts-xenial  4.4.0.185.162
  linux-image-powerpc64-smp-lts-xenial  4.4.0.185.162
  linux-image-virtual-lts-xenial  4.4.0.185.162

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/4419-1
  CVE-2020-10690, CVE-2020-10711, CVE-2020-12770, CVE-2020-13143,
  CVE-2020-8992

Package Information:
  https://launchpad.net/ubuntu/+source/linux/4.4.0-185.215
  https://launchpad.net/ubuntu/+source/linux-aws/4.4.0-1110.121
  https://launchpad.net/ubuntu/+source/linux-kvm/4.4.0-1076.83
  https://launchpad.net/ubuntu/+source/linux-raspi2/4.4.0-1135.144
  https://launchpad.net/ubuntu/+source/linux-snapdragon/4.4.0-1139.147