In the Linux kernel, the following vulnerability has been resolved: tipc:
wait and exit until all work queues are done On some host, a crash could be
triggered simply by repeating these commands several times: # modprobe tipc

tipc bearer enable media udp name UDP1 localip 127.0.0.1 # rmmod tipc []

BUG: unable to handle kernel paging request at ffffffffc096bb00 []
Workqueue: events 0xffffffffc096bb00 [] Call Trace: [] ?
process_one_work+0x1a7/0x360 [] ? worker_thread+0x30/0x390 [] ?
create_worker+0x1a0/0x1a0 [] ? kthread+0x116/0x130 [] ?
kthread_flush_work_fn+0x10/0x10 [] ? ret_from_fork+0x35/0x40 When removing
the TIPC module, the UDP tunnel sock will be delayed to release in a work
queue as sock_release() can’t be done in rtnl_lock(). If the work queue is
schedule to run after the TIPC module is removed, kernel will crash as the
work queue function cleanup_beareri() code no longer exists when trying to
invoke it. To fix it, this patch introduce a member wq_count in tipc_net to
track the numbers of work queues in schedule, and wait and exit until all
work queues are done in tipc_exit_net().