USN-3291-2: Linux kernel vulnerabilities

Ubuntu Security Notice USN-3291-2

17th May, 2017

linux-aws, linux-gke, 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 kernel.

Software description

  • linux-aws - Linux kernel for Amazon Web Services (AWS) systems
  • linux-gke - Linux kernel for Google Container Engine (GKE) systems
  • linux-raspi2 - Linux kernel for Raspberry Pi 2
  • linux-snapdragon - Linux kernel for Snapdragon Processors

Details

USN-3291-1 fixed vulnerabilities in the generic Linux kernel.
This update provides the corresponding updates for the Linux kernel
built for specific processors and cloud environments.

Dmitry Vyukov discovered that the generic SCSI (sg) subsystem in the Linux
kernel contained a stack-based buffer overflow. A local attacker with
access to an sg device could use this to cause a denial of service (system
crash) or possibly execute arbitrary code. (CVE-2017-7187)

It was discovered that a NULL pointer dereference existed in the Direct
Rendering Manager (DRM) driver for VMWare devices in the Linux kernel. A
local attacker could use this to cause a denial of service (system crash).
(CVE-2017-7261)

Li Qiang discovered that an integer overflow vulnerability existed in the
Direct Rendering Manager (DRM) driver for VMWare devices in the Linux
kernel. A local attacker could use this to cause a denial of service
(system crash) or possibly execute arbitrary code. (CVE-2017-7294)

It was discovered that an information leak existed in the set_mempolicy and
mbind compat syscalls in the Linux kernel. A local attacker could use this
to expose sensitive information (kernel memory). (CVE-2017-7616)

Update instructions

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

Ubuntu 16.04 LTS:
linux-image-gke 4.4.0.1013.15
linux-image-4.4.0-1013-gke 4.4.0-1013.13
linux-image-4.4.0-1017-aws 4.4.0-1017.26
linux-image-4.4.0-1058-snapdragon 4.4.0-1058.62
linux-image-snapdragon 4.4.0.1058.51
linux-image-aws 4.4.0.1017.20
linux-image-4.4.0-1055-raspi2 4.4.0-1055.62
linux-image-raspi2 4.4.0.1055.56

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

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

CVE-2017-7187, CVE-2017-7261, CVE-2017-7294, CVE-2017-7616