Re: [PATCH net-next 2/2] mac802154: don't deliver packets to devices that are down

[Eric Dumazet <eric.dumazet@gmail.com>]

On Tue, 2014-06-10 at 17:08 +0200, Phoebe Buckheister wrote:
> Only one WPAN devices can be active at any given time, so only deliver
> packets to that one interface that is actually up.
> 
> Signed-off-by: Phoebe Buckheister <phoebe.buckheister@itwm.fraunhofer.de>
> ---
>  net/mac802154/wpan.c |   12 +++++++-----
>  1 file changed, 7 insertions(+), 5 deletions(-)
> 
> diff --git a/net/mac802154/wpan.c b/net/mac802154/wpan.c
> index c8cfd54..1ba648e 100644
> --- a/net/mac802154/wpan.c
> +++ b/net/mac802154/wpan.c
> @@ -567,7 +567,6 @@ static int mac802154_parse_frame_start(struct sk_buff *skb,
>  void mac802154_wpans_rx(struct mac802154_priv *priv, struct sk_buff *skb)
>  {
>  	int ret;
> -	struct sk_buff *sskb;
>  	struct mac802154_sub_if_data *sdata;
>  	struct ieee802154_hdr hdr;
>  
> @@ -579,12 +578,15 @@ void mac802154_wpans_rx(struct mac802154_priv *priv, struct sk_buff *skb)
>  
>  	rcu_read_lock();
>  	list_for_each_entry_rcu(sdata, &priv->slaves, list) {
> -		if (sdata->type != IEEE802154_DEV_WPAN)
> +		if (sdata->type != IEEE802154_DEV_WPAN ||
> +		    !netif_running(sdata->dev))
>  			continue;
>  
> -		sskb = skb_clone(skb, GFP_ATOMIC);
> -		if (sskb)
> -			mac802154_subif_frame(sdata, sskb, &hdr);
> +		skb = skb_clone(skb, GFP_ATOMIC);
> +		if (skb)
> +			mac802154_subif_frame(sdata, skb, &hdr);
> +
> +		break;
>  	}
>  	rcu_read_unlock();
>  }

If this is really the case, do not clone the skb, and fix
mac802154_subif_rx().

(mac802154_wpans_rx() would always consume the skb)