In the Linux kernel, the following vulnerability has been resolved:
watchdog: at91sam9_wdt: prevent timer rearm during teardown
at91_ping() rearms the watchdog timer from its callback. timer_delete()
neither waits for a running callback nor prevents it from rearming the
timer, so probe failure or driver removal can leave the timer accessing the
devm-allocated at91wdt after it has been freed.
Use timer_shutdown_sync() on both teardown paths. It waits for a running
callback and rejects any attempt by the callback to rearm the timer.
