[Ksplice][Ubuntu-16.04-Updates] New Ksplice updates for Ubuntu 16.04 Xenial (USN-4116-1)

[Oracle Ksplice]

Synopsis: USN-4116-1 can now be patched using Ksplice
CVEs: CVE-2018-20856 CVE-2019-14283 CVE-2019-14284

Systems running Ubuntu 16.04 Xenial can now use Ksplice to patch
against the latest Ubuntu Security Notice, USN-4116-1.

INSTALLING THE UPDATES

We recommend that all users of Ksplice Uptrack running Ubuntu 16.04
Xenial install these updates.

On systems that have "autoinstall = yes" in /etc/uptrack/uptrack.conf,
these updates will be installed automatically and you do not need to
take any action.

Alternatively, you can install these updates by running:

# /usr/sbin/uptrack-upgrade -y


DESCRIPTION

* Divide-by-zero in block device driver when metadata unavailable.

When a block device's metadata becomes unavailable (for example if it is
retrieved from a separate device), the data recovery loop can in rare
cases divide by zero while calculating the remaining work, causing a
denial-of-service.


* Improved fix for Spectre v1: Bounds-check bypass in sys_ptrace().

Missing sanitizaion of array index after bounds check in the
sys_ptrace() system call could lead to a Spectre variant 1 information
leak. A local ttacker could exploit this flaw to gain information about
the running system.


* CVE-2019-14284: Denial-of-service in floppy disk formatting.

A division by zero in the setup_format_params function for the floppy
disk driver could result in a kernel crash.  A local user with access to
the floppy disk device could use this flaw to crash the system.


* CVE-2018-20856: Use-after-free in block device core.

A failure to initialize part of a structure in the block device allocation
path can lead to a use-after-free of certain kernel structures, which can
result in a kernel panic.  This could be used to cause a denial of service.


* CVE-2019-14283: Denial-of-service in floppy disk geometry setting during insertion.

Missing input validation in the floppy disk geometry setting calls could
allow a malicious local user with access to the floppy device to cause
an out-of-bounds access either crashing the system or leaking the
contents of kernel memory.


* Potential NULL dereference when setting up KVM PIT.

When attempting to create a virtual programmable interrupt timer for
a new VM, it is possible for a lock ordering issue to cause a NULL
pointer dereference, under certain conditions.  This flaw could
potentially be used to cause a denial-of-service.

SUPPORT

Ksplice support is available at ksplice-support_ww at oracle.com.