CVE-2022-49229

ptp: unregister virtual clocks when unregistering physical clock.

In the Linux kernel, the following vulnerability has been resolved: ptp: unregister virtual clocks when unregistering physical clock. When unregistering a physical clock which has some virtual clocks, unregister the virtual clocks with it. This fixes the following oops, which can be triggered by unloading a driver providing a PTP clock when it has enabled virtual clocks: BUG: unable to handle page fault for address: ffffffffc04fc4d8 Oops: 0000 [#1] PREEMPT SMP NOPTI RIP: 0010:ptp_vclock_read+0x31/0xb0 Call Trace: timecounter_read+0xf/0x50 ptp_vclock_refresh+0x2c/0x50 ? ptp_clock_release+0x40/0x40 ptp_aux_kworker+0x17/0x30 kthread_worker_fn+0x9b/0x240 ? kthread_should_park+0x30/0x30 kthread+0xe2/0x110 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork+0x22/0x30