Advisory [CVE-2026-52979] check for device unregister when creating assoc

In the Linux kernel, the following vulnerability has been resolved: net: psp: check for device unregister when creating assoc psp_assoc_device_get_locked() obtains a psp_dev reference via psp_dev_get_for_sock() (which uses psp_dev_tryget() under RCU); it then acquires psd->lock and drops the reference.

Before the lock is taken, psp_dev_unregister() can run to completion: take psd->lock, clear out state, unlock, drop the registration reference. The expectation is that the lock prevents device unregistration, but much like with netdevs special care has to be taken when "upgrading" a reference to a locked device.

Add the missing check if device is still alive. psp_dev_is_registered() exists already but had no callers, which makes me wonder if I either forgot to add this or lost the check during refactoring... A flaw was found in the Linux kernel's Platform Security Processor (PSP) network driver.

This vulnerability occurs when creating a device association, where the system fails to properly check if the device has been unregistered. A race condition exists where the device can be unregistered before a lock is acquired, leading to an invalid state.

This could potentially result in system instability or a denial of service. Red Hat severity: not rated.

Weakness: CWE-367.