In the Linux kernel, the following vulnerability has been resolved: pds_core: fix use-after-free...

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

pds_core: fix use-after-free on workqueue during remove

In pdsc_remove(), the workqueue is destroyed before pdsc_teardown() is called. This ordering allows two paths to queue work on the destroyed workqueue:

1. If pdsc_teardown() -> pdsc_devcmd_reset() times out, the error path in pdsc_devcmd_locked() queues health_work.

2. A NotifyQ event can trigger the ISR and queue work before free_irq() is called in pdsc_teardown().

Fix by moving destroy_workqueue() after pdsc_teardown() so the workqueue outlives every queuer; destroy_workqueue() then flushes any work still pending.

Draining the queued work also requires ordering the teardown so the resources that work touches are freed last:

• In pdsc_qcq_free(), after freeing the interrupt, cancel_work_sync() the queue's work and only then clear qcq->intx, so pdsc_process_adminq()'s read of qcq->intx for interrupt-credit return cannot race with the clear.

• Free adminqcq before notifyqcq: the shared adminq ISR is released when adminqcq is freed, and the adminq work accesses notifyqcq, so both must be stopped before notifyqcq is freed.