CVE-2025-40348

Description

In the Linux kernel, the following vulnerability has been resolved: slab: Avoid race on slab->obj_exts in alloc_slab_obj_exts If two competing threads enter alloc_slab_obj_exts() and one of them fails to allocate the object extension vector, it might override the valid slab->obj_exts allocated by the other thread with OBJEXTS_ALLOC_FAIL. This will cause the thread that lost this race and expects a valid pointer to dereference a NULL pointer later on. Update slab->obj_exts atomically using cmpxchg() to avoid slab->obj_exts overrides by racing threads. Thanks for Vlastimil and Suren's help with debugging.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

References

• https://git.kernel.org/stable/c/c7af5300d78460fc5037ddc77113ba3dbfe77dc0 ↗
• https://git.kernel.org/stable/c/7c34feda6a9a203c9744281f1b6671b7dad2012d ↗
• https://git.kernel.org/stable/c/6ed8bfd24ce1cb31742b09a3eb557cd008533eec ↗