CVE-2025-21807

Published Feb 27, 2025

Last updated 5 months ago

CVSS medium 5.5

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: block: fix queue freeze vs limits lock order in sysfs store methods queue_attr_store() always freezes a device queue before calling the attribute store operation. For attributes that control queue limits, the store operation will also lock the queue limits with a call to queue_limits_start_update(). However, some drivers (e.g. SCSI sd) may need to issue commands to a device to obtain limit values from the hardware with the queue limits locked. This creates a potential ABBA deadlock situation if a user attempts to modify a limit (thus freezing the device queue) while the device driver starts a revalidation of the device queue limits. Avoid such deadlock by not freezing the queue before calling the ->store_limit() method in struct queue_sysfs_entry and instead use the queue_limits_commit_update_frozen helper to freeze the queue after taking the limits lock. This also removes taking the sysfs lock for the store_limit method as it doesn't protect anything here, but creates even more nesting. Hopefully it will go away from the actual sysfs methods entirely soon. (commit log adapted from a similar patch from Damien Le Moal)
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Analyzed
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
5.5
Impact score
3.6
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Severity
MEDIUM

Weaknesses

nvd@nist.gov
CWE-667

Social media

Hype score
Not currently trending

  1. 🚨 CVE-2025-21807 ❓ 🏢 Linux - Linux 🏗️ 0327ca9d53bfbb0918867313049bba7046900f73 🔗 https://t.co/rlRjTxb3un 🔗 https://t.co/T9TzZSrden #CyberCron #VulnAlert @Linux https://t.co/lCp056sdpu

    @cybercronai

    1 Mar 2025

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  2. CVE-2025-21807 02/27/2025 08:16:03 PM In the Linux kernel, the following vulnerability has been resolved: block: fix queue freeze vs limits lock order in sysfs store methods queue_attr_store() always fr... https://t.co/dHNcj3td4o

    @CVETracker

    28 Feb 2025

    20 Impressions

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Configurations

Related CVEs

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References

Sources include official advisories and independent security research.