=========================================================================Ubuntu Security Notice USN-3657-1
May 22, 2018

linux-raspi2 vulnerabilities
=========================================================================
A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 17.10

Summary:

Several security issues were fixed in the Linux kernel.

Software Description:
- linux-raspi2: Linux kernel for Raspberry Pi 2

Details:

It was discovered that the netlink subsystem in the Linux kernel did not
properly restrict observations of netlink messages to the appropriate net
namespace. A local attacker could use this to expose sensitive information
(kernel netlink traffic). (CVE-2017-17449)

Tuba Yavuz discovered that a double-free error existed in the USBTV007
driver of the Linux kernel. A local attacker could use this to cause a
denial of service (system crash) or possibly execute arbitrary code.
(CVE-2017-17975)

It was discovered that a race condition existed in the Device Mapper
component of the Linux kernel. A local attacker could use this to cause a
denial of service (system crash). (CVE-2017-18203)

It was discovered that an infinite loop could occur in the madvise(2)
implementation in the Linux kernel in certain circumstances. A local
attacker could use this to cause a denial of service (system hang).
(CVE-2017-18208)

Silvio Cesare discovered a buffer overwrite existed in the NCPFS
implementation in the Linux kernel. A remote attacker controlling a
malicious NCPFS server could use this to cause a denial of service (system
crash) or possibly execute arbitrary code. (CVE-2018-8822)

Update instructions:

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

Ubuntu 17.10:
  linux-image-4.13.0-1020-raspi2  4.13.0-1020.21
  linux-image-raspi2              4.13.0.1020.18

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://ubuntu.com/security/notices/USN-3657-1
  CVE-2017-17449, CVE-2017-17975, CVE-2017-18203, CVE-2017-18208,
  CVE-2018-8822

Package Information:
  https://launchpad.net/ubuntu/+source/linux-raspi2/4.13.0-1020.21