CVE-2025-21817: linux kernel — Fix

Description

In the Linux kernel, the following vulnerability has been resolved: block: mark GFP_NOIO around sysfs ->store() sysfs ->store is called with queue freezed, meantime we have several ->store() callbacks(update_nr_requests, wbt, scheduler) to allocate memory with GFP_KERNEL which may run into direct reclaim code path, then potential deadlock can be caused. Fix the issue by marking NOIO around sysfs ->store()

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CVSS v3.1 Score

5.5

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-667 CWE-667

Affected Products

Vendor	Product	Versions
linux	linux_kernel	All

References

Advisories & Patches

https://git.kernel.org/stable/c/2566ce907e5d5db8a039647208e029ce559baa31 https://git.kernel.org/stable/c/7c0be4ead1f8f5f8be0803f347de0de81e3b8e1c

Frequently Asked Questions

What is CVE-2025-21817? +

In the Linux kernel, the following vulnerability has been resolved: block: mark GFP_NOIO around sysfs ->store() sysfs ->store is called with queue freezed, meantime we have several ->store() callbacks(update_nr_requests, wbt, scheduler) to allocate memory with GFP_KERNEL which may run into direct reclaim code path, then potential deadlock can be caused. Fix the issue by marking NOIO around sysfs ->store() It has a CVSS v3.1 base score of 5.5 (MEDIUM).

How severe is CVE-2025-21817? +

CVE-2025-21817 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2025-21817? +

CVE-2025-21817 affects products from linux, specifically: linux_kernel. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-21817? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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