Message-ID: <1348145505.4161.32.camel@jlt4.sipsolutions.net> (sfid-20120920_145122_836883_65F5FB8F)
Subject: Re: regression: tethering fails in 3.5 with iwlwifi
From: Johannes Berg <johannes@sipsolutions.net>
To: Eric Dumazet <edumazet@google.com>
Cc: artem.bityutskiy@linux.intel.com, linux-wireless@vger.kernel.org,
	netdev <netdev@vger.kernel.org>
Date: Thu, 20 Sep 2012 14:51:45 +0200
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On Thu, 2012-09-20 at 14:47 +0200, Johannes Berg wrote:

> >                 if (skb) {
> >                         /* deliver to local stack */
> > -                       skb->protocol = eth_type_trans(skb, dev);
> > -                       memset(skb->cb, 0, sizeof(skb->cb));
> > -                       netif_receive_skb(skb);
> > +                       if (pskb_may_pull(skb, sizeof(struct ethhdr))) {
> > +                               skb->protocol = eth_type_trans(skb, dev);
> > +                               memset(skb->cb, 0, sizeof(skb->cb));
> > +                               netif_receive_skb(skb);
> > +                       } else {
> > +                               kfree_skb(skb);
> > +                       }
> >                 }
> >         }
> 
> Yeah I was looking at the same code just now. However, we had actually
> inserted the skb_linearize() *after* eth_type_trans(), so I'm confused.

Ok actually, by the time we get here the ethernet header must be in the
skb head because we construct it from the 802.11 and llc/snap header.

johannes