Re: [PATCH v2 44/63] mac80211: Use memset_after() to clear tx status

Johannes Berg
2021-08-18T08:07:06Z

On Wed, 2021-08-18 at 09:08 +0200, Johannes Berg wrote:
> On Tue, 2021-08-17 at 23:05 -0700, Kees Cook wrote:
> >
> > @@ -275,12 +275,11 @@ static void carl9170_tx_release(struct kref *ref)
> >   if (WARN_ON_ONCE(!ar))
> >   return;
> >
> >
> >
> >
> > - BUILD_BUG_ON(
> > - offsetof(struct ieee80211_tx_info, status.ack_signal) != 20);
> > -
> > - memset(&txinfo->status.ack_signal, 0,
> > - sizeof(struct ieee80211_tx_info) -
> > - offsetof(struct ieee80211_tx_info, status.ack_signal));
> > + /*
> > + * Should this call ieee80211_tx_info_clear_status() instead of clearing
> > + * manually? txinfo->status.rates do not seem to be used here.
> > + */
>
> Since you insist, I went digging :)
>
> It should not, carl9170_tx_fill_rateinfo() has filled the rate
> information before we get to this point.

Otherwise, looks fine, FWIW.

Are you going to apply all of these together somewhere? I (we) can't,
since memset_after() doesn't exist yet.

johannes