CVE-2026-64080: Undefined Security Weakness

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

firmware: arm_ffa: Snapshot notifier callbacks under lock

Both notification handlers currently look up a notifier callback under notify_lock, drop the lock, and then dereference the returned notifier entry. A concurrent unregister can delete and free that entry in the gap, leaving the handler to dereference stale memory.

Copy the callback pointer and callback data while notify_lock is still held and invoke the callback only after the lock is dropped. This keeps the existing callback execution model while removing the use-after-free window in both the framework and non-framework notification paths.