[Ksplice][Ubuntu-20.04-Updates] New Ksplice updates for Ubuntu 20.04 Focal (USN-4576-1)

[Oracle Ksplice]

Synopsis: USN-4576-1 can now be patched using Ksplice
CVEs: CVE-2020-14314 CVE-2020-14385 CVE-2020-16119 CVE-2020-16120 CVE-2020-25285 CVE-2020-25641

Systems running Ubuntu 20.04 Focal can now use Ksplice to patch
against the latest Ubuntu Security Notice, USN-4576-1.

INSTALLING THE UPDATES

We recommend that all users of Ksplice Uptrack running Ubuntu 20.04
Focal 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

* CVE-2020-16120: Read permission bypass with overlay filesystem.

A logic error in the overlay filesystem may cause the kernel to not properly
perform all required permission checks. A local attacker could use this to
bypass intended access restrictions.


* CVE-2020-14314: Denial-of-service in ext4 file system due to a broken indexing.

A memory out-of-bounds reads could happen in ext4 file system due to
a broken indexing. This flaw could allow a local user to crash the
system and cause a denial-of-service.


* CVE-2020-25285: Denial-of-service in sysctls of Linux Memory Manager.

A race condition in sysctls of Linux Kernel Virtual Memory Manager
could lead to NULL pointer dereference. A local attacker could use
this flaw to cause a denial-of-service.


* CVE-2020-14385: Denial of service in XFS filesystem.

A logic error in the XFS filesystem could cause an inode with a valid
extended attribute to be wrongly flagged as corrupted leading to the XFS
filesystem shutdown. A local, unprivileged user could use this flaw for
a denial-of-service.


* CVE-2020-16119: Use-after-free when reusing a DCCP socket.

A logic error in pointer handling when reusing a DCCP socket could lead
to a use-after-free. A local attacker could use this flaw to cause a
denial-of-service or escalate privileges.


* CVE-2020-25641: Denial-of-service in biovec when zero-length biovec is issued.

A flaw in biovec implementation could cause the system to enter
an infinite loop when a zero-length biovec request is issued to
the block subsystem. A local, non privileged user could exploit
this vulnerability to cause a denial-of-service.


* Add ftrace safety guard for existing Ksplice updates.

Ftrace is generally incompatible with Ksplice's patching process; it must
be disabled when patches are applied. Prevent crashes in patching due to
functions under active ftrace while patching.


* Clean up ftrace safety guard for existing Ksplice updates.

Ftrace is generally incompatible with Ksplice's patching process; it must
be disabled when patches are applied. Prevent crashes in patching due to
functions under active ftrace while patching.

SUPPORT

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