Re: [PATCH] net/usb: cancel pending work when unbinding smsc75xx

[David Miller]

From: Yu Zhao <yuzhao@xxxxxxxxxx>
Date: Fri, 28 Sep 2018 17:04:30 -0600

> Cancel pending work before freeing smsc75xx private data structure
> during binding. This fixes the following crash in the driver:
> 
> BUG: unable to handle kernel NULL pointer dereference at 0000000000000050
> IP: mutex_lock+0x2b/0x3f
> <snipped>
> Workqueue: events smsc75xx_deferred_multicast_write [smsc75xx]
> task: ffff8caa83e85700 task.stack: ffff948b80518000
> RIP: 0010:mutex_lock+0x2b/0x3f
> <snipped>
> Call Trace:
>  smsc75xx_deferred_multicast_write+0x40/0x1af [smsc75xx]
>  process_one_work+0x18d/0x2fc
>  worker_thread+0x1a2/0x269
>  ? pr_cont_work+0x58/0x58
>  kthread+0xfa/0x10a
>  ? pr_cont_work+0x58/0x58
>  ? rcu_read_unlock_sched_notrace+0x48/0x48
>  ret_from_fork+0x22/0x40
> 
> Signed-off-by: Yu Zhao <yuzhao@xxxxxxxxxx>

Applied and queued up for -stable.