Riskcovery

CVE-2025-21786

workqueue: Put the pwq after detaching the rescuer from the pool

State
Published
Severity
7.8 High
Published
Feb 27, 2025
Updated
Aug 5, 2026
Reserved
Dec 29, 2024

Read the record on cve.org

Description

In the Linux kernel, the following vulnerability has been resolved:

workqueue: Put the pwq after detaching the rescuer from the pool

The commit 68f83057b913("workqueue: Reap workers via kthread_stop() and remove detach_completion") adds code to reap the normal workers but mistakenly does not handle the rescuer and also removes the code waiting for the rescuer in put_unbound_pool(), which caused a use-after-free bug reported by Cheung Wall.

To avoid the use-after-free bug, the pool’s reference must be held until the detachment is complete. Therefore, move the code that puts the pwq after detaching the rescuer from the pool.

Scores

CVSSScoreVectorSource
3.17.8 HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HLinux
3.17.8 HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HCISA-ADP

Weaknesses

Affected Products

ProductVersions
LinuxLinux
  • 68f83057b913467a999e1bf9e0da6a119668f769 to before e7c16028a424dd35be1064a68fa318be4359310fAffected
  • 68f83057b913467a999e1bf9e0da6a119668f769 to before 835b69c868f53f959d4986bbecd561ba6f38e492Affected
  • 68f83057b913467a999e1bf9e0da6a119668f769 to before e76946110137703c16423baf6ee177b751a34b7eAffected
LinuxLinux
  • 6.11Affected
  • before 6.11Not affected
  • 6.12.16 through 6.12.*Not affected
  • 6.13.4 through 6.13.*Not affected
  • 6.14 and laterNot affected

References

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