==========================================================================
Ubuntu Security Notice USN-6357-1
September 11, 2023

linux-ibm, linux-ibm-5.4 vulnerabilities
==========================================================================

A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS (Available with Ubuntu Pro)

Summary:

Several security issues were fixed in the Linux kernel.

Software Description:
- linux-ibm: Linux kernel for IBM cloud systems
- linux-ibm-5.4: Linux kernel for IBM cloud systems

Details:

Daniel Moghimi discovered that some Intel(R) Processors did not properly
clear microarchitectural state after speculative execution of various
instructions. A local unprivileged user could use this to obtain to
sensitive information. (CVE-2022-40982)

Ruihan Li discovered that the bluetooth subsystem in the Linux kernel did
not properly perform permissions checks when handling HCI sockets. A
physically proximate attacker could use this to cause a denial of service
(bluetooth communication). (CVE-2023-2002)

Tavis Ormandy discovered that some AMD processors did not properly handle
speculative execution of certain vector register instructions. A local
attacker could use this to expose sensitive information. (CVE-2023-20593)

Zi Fan Tan discovered that the binder IPC implementation in the Linux
kernel contained a use-after-free vulnerability. A local attacker could use
this to cause a denial of service (system crash) or possibly execute
arbitrary code. (CVE-2023-21255)

Juan Jose Lopez Jaimez, Meador Inge, Simon Scannell, and Nenad Stojanovski
discovered that the BPF verifier in the Linux kernel did not properly mark
registers for precision tracking in certain situations, leading to an out-
of-bounds access vulnerability. A local attacker could use this to cause a
denial of service (system crash) or possibly execute arbitrary code.
(CVE-2023-2163)

Zheng Zhang discovered that the device-mapper implementation in the Linux
kernel did not properly handle locking during table_clear() operations. A
local attacker could use this to cause a denial of service (kernel
deadlock). (CVE-2023-2269)

It was discovered that the DVB Core driver in the Linux kernel did not
properly handle locking events in certain situations. A local attacker
could use this to cause a denial of service (kernel deadlock).
(CVE-2023-31084)

It was discovered that the kernel->user space relay implementation in the
Linux kernel did not properly perform certain buffer calculations, leading
to an out-of-bounds read vulnerability. A local attacker could use this to
cause a denial of service (system crash) or expose sensitive information
(kernel memory). (CVE-2023-3268)

It was discovered that the video4linux driver for Philips based TV cards in
the Linux kernel contained a race condition during device removal, leading
to a use-after-free vulnerability. A physically proximate attacker could
use this to cause a denial of service (system crash) or possibly execute
arbitrary code. (CVE-2023-35823)

It was discovered that the SDMC DM1105 PCI device driver in the Linux
kernel contained a race condition during device removal, leading to a use-
after-free vulnerability. A physically proximate attacker could use this to
cause a denial of service (system crash) or possibly execute arbitrary
code. (CVE-2023-35824)

It was discovered that the Renesas USB controller driver in the Linux
kernel contained a race condition during device removal, leading to a use-
after-free vulnerability. A privileged attacker could use this to cause a
denial of service (system crash) or possibly execute arbitrary code.
(CVE-2023-35828)

It was discovered that the universal 32bit network packet classifier
implementation in the Linux kernel did not properly perform reference
counting in some situations, leading to a use-after-free vulnerability. A
local attacker could use this to cause a denial of service (system crash)
or possibly execute arbitrary code. (CVE-2023-3609)

It was discovered that the Quick Fair Queueing network scheduler
implementation in the Linux kernel contained an out-of-bounds write
vulnerability. A local attacker could use this to cause a denial of service
(system crash) or possibly execute arbitrary code. (CVE-2023-3611)

It was discovered that the network packet classifier with
netfilter/firewall marks implementation in the Linux kernel did not
properly handle reference counting, leading to a use-after-free
vulnerability. A local attacker could use this to cause a denial of service
(system crash) or possibly execute arbitrary code. (CVE-2023-3776)

Update instructions:

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

Ubuntu 20.04 LTS:
   linux-image-5.4.0-1056-ibm      5.4.0-1056.61
   linux-image-ibm-lts-20.04       5.4.0.1056.85

Ubuntu 18.04 LTS (Available with Ubuntu Pro):
   linux-image-5.4.0-1056-ibm      5.4.0-1056.61~18.04.1
   linux-image-ibm                 5.4.0.1056.67

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-6357-1
   CVE-2022-40982, CVE-2023-2002, CVE-2023-20593, CVE-2023-21255,
   CVE-2023-2163, CVE-2023-2269, CVE-2023-31084, CVE-2023-3268,
   CVE-2023-35823, CVE-2023-35824, CVE-2023-35828, CVE-2023-3609,
   CVE-2023-3611, CVE-2023-3776

Package Information:
   https://launchpad.net/ubuntu/+source/linux-ibm/5.4.0-1056.61