CVE-2025-21786

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.

The following products are affected by CVE-2025-21786 vulnerability.

Here, you will find a curated list of external links that provide in-depth information to CVE-2025-21786.

URL	Resource
https://git.kernel.org/stable/c/835b69c868f53f959d4986bbecd561ba6f38e492
https://git.kernel.org/stable/c/e76946110137703c16423baf6ee177b751a34b7e
https://git.kernel.org/stable/c/e7c16028a424dd35be1064a68fa318be4359310f
https://lore.kernel.org/linux-cve-announce/2025022608-CVE-2025-21786-f31d@gregkh/T
https://nvd.nist.gov/vuln/detail/CVE-2025-21786
https://www.cve.org/CVERecord?id=CVE-2025-21786