Ubuntu 20.04 LTS: USN-7234-1 critical: kernel denial of service

ubuntu

January 28, 2025

Several security issues were fixed in the Linux kernel.

Summary

Several security issues were fixed in the Linux kernel.

Software Description:

- linux: Linux kernel

- linux-bluefield: Linux kernel for NVIDIA BlueField platforms

- linux-gcp: Linux kernel for Google Cloud Platform (GCP) systems

- linux-ibm: Linux kernel for IBM cloud systems

- linux-kvm: Linux kernel for cloud environments

- linux-oracle: Linux kernel for Oracle Cloud systems

- linux-raspi: Linux kernel for Raspberry Pi systems

- linux-gcp-5.4: Linux kernel for Google Cloud Platform (GCP) systems

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

- linux-oracle-5.4: Linux kernel for Oracle Cloud systems

Details:

Ye Zhang and Nicolas Wu discovered that the io_uring subsystem in the Linux

kernel did not properly handle locking for rings with IOPOLL, leading to a

double-free vulnerability. A local attacker could use this to cause a

denial of service (system crash) or possibly execute arbitrary code.

(CVE-2023-21400)

Several security issues were discovered ...

Read the Full Advisory

Topics Covered

security advisory denial of service software update code execution Ubuntu kernel

Update Instructions

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

Ubuntu 20.04 LTS
   linux-image-5.4.0-1085-ibm      5.4.0-1085.90
   linux-image-5.4.0-1098-bluefield  5.4.0-1098.105
   linux-image-5.4.0-1122-raspi    5.4.0-1122.134
   linux-image-5.4.0-1126-kvm      5.4.0-1126.134
   linux-image-5.4.0-1137-oracle   5.4.0-1137.146
   linux-image-5.4.0-1142-gcp      5.4.0-1142.151
   linux-image-5.4.0-205-generic   5.4.0-205.225
   linux-image-5.4.0-205-generic-lpae  5.4.0-205.225
   linux-image-5.4.0-205-lowlatency  5.4.0-205.225
   linux-image-bluefield           5.4.0.1098.94
   linux-image-gcp-lts-20.04       5.4.0.1142.144
   linux-image-generic             5.4.0.205.201
   linux-image-generic-lpae        5.4.0.205.201
   linux-image-ibm-lts-20.04       5.4.0.1085.114
   linux-image-kvm                 5.4.0.1126.122
   linux-image-lowlatency          5.4.0.205.201
   linux-image-oem                 5.4.0.205.201
   linux-image-oem-osp1            5.4.0.205.201
   linux-image-oracle-lts-20.04    5.4.0.1137.130
   linux-image-raspi               5.4.0.1122.152
   linux-image-raspi2              5.4.0.1122.152
   linux-image-virtual             5.4.0.205.201

Ubuntu 18.04 LTS
   linux-image-5.4.0-1085-ibm      5.4.0-1085.90~18.04.1
                                   Available with Ubuntu Pro
   linux-image-5.4.0-1137-oracle   5.4.0-1137.146~18.04.1
                                   Available with Ubuntu Pro
   linux-image-5.4.0-1142-gcp      5.4.0-1142.151~18.04.1
                                   Available with Ubuntu Pro
   linux-image-gcp                 5.4.0.1142.151~18.04.1
                                   Available with Ubuntu Pro
   linux-image-ibm                 5.4.0.1085.90~18.04.1
                                   Available with Ubuntu Pro
   linux-image-oracle              5.4.0.1137.146~18.04.1
                                   Available with Ubuntu Pro

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.