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

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