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Back to active CVEs
Medium · CVSS 5.5CVE-2025-21807

block: fix queue freeze vs limits lock order in sysfs store methodsCVE-2025-21807

Answer in brief

CVE-2025-21807 records a Medium severity (CVSS 5.5) vulnerability in block: fix queue freeze vs limits lock order in sysfs store methods. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Feb 27, 2025Updated Nov 5, 2026Source checked Nov 5, 2026First seen by HOL Nov 5, 2026Material review Nov 5, 2026
Upstream Advisory

Key facts

Risk
Medium · CVSS 5.5
Exploitation
Not marked as known exploited
Affected software
3 mapped packages or products
Fix availability
Available

Why this deserves its current priority

CVSS is 5.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Affected products and reported versions
ProductAffected versionsFixed versions
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*Not reportedNot reported
Mapped affected packages and fixed versions
PackageAffected rangeFixed version
Linux/Linuxgeneric>=0327ca9d53bfbb0918867313049bba7046900f73 <1645cd7fd42c236c952e9228badcac4fea1829ea || >=0327ca9d53bfbb0918867313049bba7046900f73 <8985da5481562e96b95e94ed8e5cc9b6565eb82b || >=0327ca9d53bfbb0918867313049bba7046900f73 <c99f66e4084a62a2cc401c4704a84328aeddc9ec1645cd7fd42c236c952e9228badcac4fea1829ea, 8985da5481562e96b95e94ed8e5cc9b6565eb82b, c99f66e4084a62a2cc401c4704a84328aeddc9ec
Linux/Linuxgeneric6.9Not reported

Recommended response

  1. 1Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
  2. 2Review the reported fix. Update Linux/Linux to 1645cd7fd42c236c952e9228badcac4fea1829ea if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

  1. Published upstream

    Feb 27, 2025

    Evidence: source:cvelist:source_dates:source-dates:record
  2. Source modified

    Nov 5, 2026

    Evidence: source:cvelist:source_dates:source-dates:record
  3. First seen by HOL

    Nov 5, 2026

Sources and claim methodology

  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
Upstream source 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)

Quoted source text, attributed separately from HOL analysis.

Related CVEs

  • filelock: On Windows an oplock on a soft lock's marker holds SoftFileLock.acquire() past its timeout and blocks the stale breakAlso CWE-667

Record context

Vulnerability class
Vulnerability
EPSS
Not reported
CWE IDs
CWE-667
Source
CVE List V5
Source checked
Nov 5, 2026
References
3 linked sources
Open source record