---
id: CVE-2024-53167
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  nfs/blocklayout: Don't attempt unregister for invalid block device

  Since commit d869da91cccb ("nfs/blocklayout: Fix premature PR key
  unregistration") an unmount of a p…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  nfs/blocklayout: Don't attempt unregister for invalid block device

  Since commit d869da91cccb ("nfs/blocklayout: Fix premature PR key
  unregistration") an unmount of a p…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-476
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 6.11, < 6.11.11'
  - 'linux_kernel >= 6.12, < 6.12.2'
patched:
  - linux_kernel 6.12.2
published: '2024-12-27'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T22:18:01.110'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2024-53167'
references:
  - url: 'https://git.kernel.org/stable/c/3402704a424f34bbcca7f4a4503859357f422217'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/3a4ce14d9a6b868e0787e4582420b721c04ee41e'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/faa4bacfaeed827a4ca8cb8529a3ce65a9e8ef46'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
epss: 0.00644
epssPercentile: 0.50677
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-10-15T21:40:55.992319Z'
ingestedAt: '2026-10-15T22:48:25.442Z'
---

## Overview

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

nfs/blocklayout: Don't attempt unregister for invalid block device

Since commit d869da91cccb ("nfs/blocklayout: Fix premature PR key
unregistration") an unmount of a pNFS SCSI layout-enabled NFS may
dereference a NULL block_device in:

  bl_unregister_scsi+0x16/0xe0 [blocklayoutdriver]
  bl_free_device+0x70/0x80 [blocklayoutdriver]
  bl_free_deviceid_node+0x12/0x30 [blocklayoutdriver]
  nfs4_put_deviceid_node+0x60/0xc0 [nfsv4]
  nfs4_deviceid_purge_client+0x132/0x190 [nfsv4]
  unset_pnfs_layoutdriver+0x59/0x60 [nfsv4]
  nfs4_destroy_server+0x36/0x70 [nfsv4]
  nfs_free_server+0x23/0xe0 [nfs]
  deactivate_locked_super+0x30/0xb0
  cleanup_mnt+0xba/0x150
  task_work_run+0x59/0x90
  syscall_exit_to_user_mode+0x217/0x220
  do_syscall_64+0x8e/0x160

This happens because even though we were able to create the
nfs4_deviceid_node, the lookup for the device was unable to attach the
block device to the pnfs_block_dev.

If we never found a block device to register, we can avoid this case with
the PNFS_BDEV_REGISTERED flag.  Move the deref behind the test for the
flag.

## Affected

- `linux_kernel >= 6.11, < 6.11.11`
- `linux_kernel >= 6.12, < 6.12.2`

## Remediation

Upgrade past the affected range:

- `linux_kernel 6.12.2`