CVE-2026-74314

Technical Description

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

bpf: Cancel special fields on map value recycle

Map update and delete paths currently call bpf_obj_free_fields() when a

value is being replaced or recycled. That makes field destruction depend

on the context of the update/delete operation. For tracing programs this

can include NMI context, where referenced kptr destructors, uptr

unpinning, and graph root destruction are not generally safe.

Introduce bpf_obj_cancel_fields() for the reusable-value path. It only

performs NMI-safe cleanup for timer, workqueue, and task_work fields.

Fields that need full destruction are left attached to the recycled value

and are destroyed by the final cleanup path instead.

Switch array and hashtab update/delete/recycle paths to this cancel

helper. Keep bpf_obj_free_fields() for final map destruction and for

bpf_mem_alloc destructors. Preallocated hashtabs do not have allocator

destructors, so teardown continues to walk the normal and e

Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

References