1. Ubuntu Security Notices
  2. USN-4710-1

USN-4710-1: Linux kernel vulnerability

Publication date

3 February 2021

Overview

The system could be made to crash under certain conditions.

Releases

Packages

  • linux - Linux kernel
  • linux-hwe - Linux hardware enablement (HWE) kernel

Details

Kiyin (尹亮) discovered that the perf subsystem in the Linux kernel did
not properly deallocate memory in some situations. A privileged attacker
could use this to cause a denial of service (kernel memory exhaustion).

Kiyin (尹亮) discovered that the perf subsystem in the Linux kernel did
not properly deallocate memory in some situations. A privileged attacker
could use this to cause a denial of service (kernel memory exhaustion).

Update instructions

After a standard system update you need to reboot your computer to make all the necessary changes.

Learn more about how to get the fixes.

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.

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

Ubuntu Release Package Version
18.04 bionic linux-image-4.15.0-135-generic –  4.15.0-135.139
linux-image-4.15.0-135-generic-lpae –  4.15.0-135.139
linux-image-4.15.0-135-lowlatency –  4.15.0-135.139
linux-image-generic –  4.15.0.135.122
linux-image-generic-lpae –  4.15.0.135.122
linux-image-lowlatency –  4.15.0.135.122
linux-image-virtual –  4.15.0.135.122
16.04 xenial linux-image-4.15.0-133-generic –  4.15.0-133.137~16.04.1
linux-image-4.15.0-133-generic-lpae –  4.15.0-133.137~16.04.1
linux-image-4.15.0-133-lowlatency –  4.15.0-133.137~16.04.1
linux-image-generic-hwe-16.04 –  4.15.0.133.131
linux-image-generic-lpae-hwe-16.04 –  4.15.0.133.131
linux-image-lowlatency-hwe-16.04 –  4.15.0.133.131
linux-image-oem –  4.15.0.133.131
linux-image-virtual-hwe-16.04 –  4.15.0.133.131

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References

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