Linux Kernel Est Timer Fix

MEDIUM (5.5) Patch Available Patch Patch Patch

Threat Intelligence

Medium Risk - Detectable
EPSS Score: 0.02% chance of exploitation (percentile: 3%)
🔍 Detection Tools: OSV.dev
⚔️ Exploit Availability: No public exploits found

How we test →

What is it?

The Linux kernel's estimator timer is a mechanism used to schedule tasks. However, when the PREEMPT_RT scheduling option is enabled, this timer can be preempted, leading to potential issues with task scheduling and timing.

Am I affected?

Specific version info not stated in the advisory.

Affected Products

Linux Kernel Team / Linux Kernel

How to fix

To fix this issue, update your Linux kernel to version 5.17 or later. Alternatively, you can apply the patch manually by applying the following patches:

  • Patch 1: https://git.kernel.org/stable/c/9f74c0ea9b26d1505d55b61e36b1623dd347e1d1
  • Patch 2: https://git.kernel.org/stable/c/a22ec2ee824be30803068a52f78f7ffe3bc879fb
  • Patch 3: https://git.kernel.org/stable/c/e79923824c48b930609680be04cb29253fc4a17d

Immediate mitigations include disabling the PREEMPT_RT scheduling option or restricting network access to prevent potential issues.

References