---
id: CVE-2024-38570
title: 'gfs2: Fix potential glock use-after-free on unmount'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  gfs2: Fix potential glock use-after-free on unmount

  When a DLM lockspace is released and there ares still locks in that
  lockspace, DLM will unlock those locks automati…
severity: critical
cvss: 9.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
cvssSource: cna
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= fb6791d100d1bba20b5cdbc4912e1f7086ec60f8 <
    94b32a85d1a76ae4f1b42a88677fa20b20187729
  - >-
    Linux >= fb6791d100d1bba20b5cdbc4912e1f7086ec60f8 <
    0636b34b44589b142700ac137b5f69802cfe2e37
  - >-
    Linux >= fb6791d100d1bba20b5cdbc4912e1f7086ec60f8 <
    e42e8a24d7f02d28763d16ca7ec5fc6d1f142af0
  - >-
    Linux >= fb6791d100d1bba20b5cdbc4912e1f7086ec60f8 <
    501cd8fabf621d10bd4893e37f6ce6c20523c8ca
  - >-
    Linux >= fb6791d100d1bba20b5cdbc4912e1f7086ec60f8 <
    d98779e687726d8f8860f1c54b5687eec5f63a73
  - Linux 3.8
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2024-09-10T17:14:22.126008Z'
published: '2024-06-19'
updated: '2026-10-30'
sourceUpdated: '2026-10-30T12:18:30.366Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2024-38570'
references:
  - url: 'https://git.kernel.org/stable/c/94b32a85d1a76ae4f1b42a88677fa20b20187729'
  - url: 'https://git.kernel.org/stable/c/0636b34b44589b142700ac137b5f69802cfe2e37'
  - url: 'https://git.kernel.org/stable/c/e42e8a24d7f02d28763d16ca7ec5fc6d1f142af0'
  - url: 'https://git.kernel.org/stable/c/501cd8fabf621d10bd4893e37f6ce6c20523c8ca'
  - url: 'https://git.kernel.org/stable/c/d98779e687726d8f8860f1c54b5687eec5f63a73'
tags:
  - cve.org
epss: 0.00676
epssPercentile: 0.5252
ingestedAt: '2026-11-03T12:44:28.817Z'
---

## Overview

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

gfs2: Fix potential glock use-after-free on unmount

When a DLM lockspace is released and there ares still locks in that
lockspace, DLM will unlock those locks automatically.  Commit
fb6791d100d1b started exploiting this behavior to speed up filesystem
unmount: gfs2 would simply free glocks it didn't want to unlock and then
release the lockspace.  This didn't take the bast callbacks for
asynchronous lock contention notifications into account, which remain
active until until a lock is unlocked or its lockspace is released.

To prevent those callbacks from accessing deallocated objects, put the
glocks that should not be unlocked on the sd_dead_glocks list, release
the lockspace, and only then free those glocks.

As an additional measure, ignore unexpected ast and bast callbacks if
the receiving glock is dead.

## Affected

- `Linux >= fb6791d100d1bba20b5cdbc4912e1f7086ec60f8 < 94b32a85d1a76ae4f1b42a88677fa20b20187729`
- `Linux >= fb6791d100d1bba20b5cdbc4912e1f7086ec60f8 < 0636b34b44589b142700ac137b5f69802cfe2e37`
- `Linux >= fb6791d100d1bba20b5cdbc4912e1f7086ec60f8 < e42e8a24d7f02d28763d16ca7ec5fc6d1f142af0`
- `Linux >= fb6791d100d1bba20b5cdbc4912e1f7086ec60f8 < 501cd8fabf621d10bd4893e37f6ce6c20523c8ca`
- `Linux >= fb6791d100d1bba20b5cdbc4912e1f7086ec60f8 < d98779e687726d8f8860f1c54b5687eec5f63a73`
- `Linux 3.8`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.