Re: [PATCH 3/3] p54: zero-out rx_status

[Johannes Berg <johannes@sipsolutions.net>]

On Tue, 2012-12-11 at 16:08 +0100, Christian Lamparter wrote:
> On Tuesday, December 11, 2012 02:55:05 PM Gabor Juhos wrote:
> > In commit 'mac80211: support radiotap vendor namespace RX data'
> > new fields were added to 'struct ieee80211_rx_status'.
> > The ath5k driver does not initializes those fields and
>       ^^^^^ p54?!
> 
> > this can cause unexpected behaviour. The patch ensures
> > that each field gets initialized with zeroes.
> 
> Actually, when the skb is alloced/initialized by
> __alloc_skb, the skb->cb is already zeroed (which
> is where the ieee80211_rx_status will be stored).
> 
> And while p54 recycles command response skbs, the 
> driver does not touch the skb->cb of 802.11 skbs,
> until the frame is destined for ieee80211_rx_irqsave.
> 
> If this issue just popped up now, I suspect that 
> something else is silently corrupting our SKBs 
> [or can anybody see how rt2x00 hit this issue?]

When I reviewed the drivers, I didn't think there was a problem in any
of them but iwlwifi & iwlegacy which I fixed, for the reasons you
mention above. So I'm just as confused as you are, I guess :)

johannes