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.
Advisories

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Fixes

Solution

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Workaround

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History

Thu, 24 Sep 2026 16:00:00 +0000

Type Values Removed Values Added
Description 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.
Title locking/lockdep: Fix NULL pointer dereference in __lock_set_class()
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

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cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-09-24T15:51:59.638Z

Reserved: 2026-09-17T16:02:15.097Z

Link: CVE-2026-93261

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-09-24T16:17:22.780

Modified: 2026-09-24T16:17:22.780

Link: CVE-2026-93261

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses

No weakness.