Re: [PATCH 1/1] net: check dev->reg_state before deref of napi netdev_ops

[Cong Wang]

On Sun, Mar 11, 2018 at 12:22 PM, Josh Elsasser <jelsasser@xxxxxxxxxxx> wrote:
> init_dummy_netdev() leaves its netdev_ops pointer zeroed. This leads
> to a NULL pointer dereference when sk_busy_loop fires against an iwlwifi
> wireless adapter and checks napi->dev->netdev_ops->ndo_busy_poll.
>
> Avoid this by ensuring that napi->dev is not a dummy device before
> dereferencing napi dev's netdev_ops, preventing the following panic:

Hmm, how about just checking ->netdev_ops? Checking reg_state looks
odd, although works.