CVE-2023-52509 ravb: Fix use-after-free issue in ravb_tx_timeout_work()

In the Linux kernel, the following vulnerability has been resolved: ravb: Fix use-after-free issue in ravbtxtimeoutwork The ravbstop should call cancelworksync. Otherwise, ravbtxtimeoutwork is possible to use the freed priv after ravbremove was called like below: CPU0 CPU1 ravbtxtimeout ravbremov...