---
id: CVE-2026-93261
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  locking/lockdep: Fix NULL pointer dereference in __lock_set_class()

  register_lock_class() can return NULL when the lock class pool is
  exhausted, graph_lock() fails, or…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  locking/lockdep: Fix NULL pointer dereference in __lock_set_class()

  register_lock_class() can return NULL when the lock class pool is
  exhausted, graph_lock() fails, or…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 64aa348edc617dea17bbd01ddee4e47886d5ec8c <
    f6093ff67ea6e347574819ed23e96e0f82a25ffc
  - >-
    Linux >= 64aa348edc617dea17bbd01ddee4e47886d5ec8c <
    59a5c7dd331a3dab48100e1ef8e9bb4f9132a2b2
  - >-
    Linux >= 64aa348edc617dea17bbd01ddee4e47886d5ec8c <
    f56e54fd24f05e9de528fcb77f6084f80c8066ce
  - >-
    Linux >= 64aa348edc617dea17bbd01ddee4e47886d5ec8c <
    5c3bff6cf26e6a54fbf8b893a879c32824d2d50d
  - >-
    Linux >= 64aa348edc617dea17bbd01ddee4e47886d5ec8c <
    b2113dcd8238bf00ce37a34e67b29cf31d32a545
  - >-
    Linux >= 64aa348edc617dea17bbd01ddee4e47886d5ec8c <
    e7c69c6695d84220847cca62a45e879e71e79e9d
  - >-
    Linux >= 64aa348edc617dea17bbd01ddee4e47886d5ec8c <
    9be10f49dfc2e4b472b3a5f346483b67374774b8
  - >-
    Linux >= 64aa348edc617dea17bbd01ddee4e47886d5ec8c <
    7577e00b9ab506202b9f1a33de3cc8cc6413a4db
  - Linux 2.6.27
published: '2026-09-24'
updated: '2026-09-24'
sourceUpdated: '2026-09-24T16:17:22.780'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-93261'
references:
  - url: 'https://git.kernel.org/stable/c/59a5c7dd331a3dab48100e1ef8e9bb4f9132a2b2'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/5c3bff6cf26e6a54fbf8b893a879c32824d2d50d'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/7577e00b9ab506202b9f1a33de3cc8cc6413a4db'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/9be10f49dfc2e4b472b3a5f346483b67374774b8'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/b2113dcd8238bf00ce37a34e67b29cf31d32a545'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/e7c69c6695d84220847cca62a45e879e71e79e9d'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/f56e54fd24f05e9de528fcb77f6084f80c8066ce'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/f6093ff67ea6e347574819ed23e96e0f82a25ffc'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
ingestedAt: '2026-09-24T16:47:15.835Z'
---

## Overview

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

locking/lockdep: Fix NULL pointer dereference in __lock_set_class()

register_lock_class() can return NULL when the lock class pool is
exhausted, graph_lock() fails, or key validation fails. However,
__lock_set_class() uses the return value directly in pointer arithmetic
without a NULL check:

  class = register_lock_class(lock, subclass, 0);
  hlock->class_idx = class - lock_classes;

If class is NULL, this computes a wild offset that corrupts
hlock->class_idx. The subsequent reacquire_held_locks() call will
invoke hlock_class() with this corrupted index, leading to a NULL or
out-of-bounds pointer dereference.

Add the missing NULL check, consistent with how __lock_acquire() already
handles this case at the same call site.

## Remediation

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