Re: [PATCH] mac80211 : fix a race with update_tkip_key

gregor kowski
2009-06-09T17:48:29Z

On Tue, Jun 9, 2009 at 4:02 PM, Johannes Berg<johannes@sipsolutions.net> wrote:
> On Mon, 2009-06-08 at 19:51 +0200, gregor kowski wrote:
>
>> > There's a quite obvious disconnect between what your patch does and what
>> > your description says, please fix one of them. As it is, the patch only
>> > skips the IV rollover which is *completely* wrong because it will call
>> > the function for *every* packet.
>
>> I don't understand what you mean : the callback will be called for
>> every packet the hardware doesn't decrypted. If the hardware decrypt
>> the packet, only_iv is set and we don't go here.
>
> Right. But drivers are free to even only _encrypt_ tkip frames and never
> _decrypt_ them after having accepted a hardware key, iow that is
> perfectly valid behaviour and I don't think we should keep uploading the
> key to the driver. Worst case is that the proper upload fails and we
> decrypt all frames in software until the next rollover.
>
What's the point of setting the tkip callback if we aren't interested
in decrypting data by hardware ?