4.7 - USN-3597-1

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

Details:

USNS 3541-1 and 3523-1 provided mitigations for Spectre and Meltdown (CVE-2017-5715, CVE-2017-5753, CVE-2017-5754) for the i386, amd64, and ppc64el architectures in Ubuntu 17.10. This update provides the corresponding mitigations for the arm64 architecture. Original advisory details:

Jann Horn discovered that microprocessors utilizing speculative execution
and indirect branch prediction may allow unauthorized memory reads via
sidechannel attacks. This flaw is known as Meltdown. A local attacker could
use this to expose sensitive information, including kernel memory.
(CVE-2017-5754)

Jann Horn discovered that microprocessors utilizing speculative execution
and branch prediction may allow unauthorized memory reads via sidechannel
attacks. This flaw is known as Spectre. A local attacker could use this to
expose sensitive information, including kernel memory. (CVE-2017-5715,
CVE-2017-5753)

Update instructions:

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

Ubuntu 17.10:
linux-image-4.13.0-1015-raspi2 4.13.0-1015.16
linux-image-4.13.0-37-generic 4.13.0-37.42
linux-image-4.13.0-37-generic-lpae 4.13.0-37.42
linux-image-4.13.0-37-lowlatency 4.13.0-37.42
linux-image-generic 4.13.0.37.40
linux-image-generic-lpae 4.13.0.37.40
linux-image-lowlatency 4.13.0.37.40
linux-image-raspi2 4.13.0.1015.13

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-3597-1,
https://usn.ubuntu.com/usn/usn-3523-1,
https://usn.ubuntu.com/usn/usn-3541-1,
CVE-2017-5715, CVE-2017-5753, CVE-2017-5754

Package Information:
https://launchpad.net/ubuntu/+source/linux/4.13.0-37.42
https://launchpad.net/ubuntu/+source/linux-raspi2/4.13.0-1015.16