[PATCHv2] offchannel: Cancel the pending_action TX wait, before starting new one.

[Krishna Chaitanya]

On Mon, Nov 23, 2015 at 12:45 AM, Jouni Malinen <j at w1.fi> wrote:
>
> On Mon, Nov 02, 2015 at 08:40:28PM +0530, Chaitanya T K wrote:
> > From: tkc <chaitanya.mgit at gmail.com>
> >
> > Before the tx_status is received for the action frame, if we
> > get another request, we respond to that by freeing the memory
> > for pending_action_tx, but we don't cancel the TX wait, so
> > in the kernel the ROC will not be cancelled.
> >
> > Due to above issue, wpa_supplicant assumes that all pending
> > RoC's are cancelled and proceeds with interface creation and
> > connection, where as state in mac80211/driver will be roc_in_progress.
> >
> > This is leading to issues at driver level.
> >
> > Signed-off-by: Chaitanya T K <chaitanya.mgit at gmail.com>
> > ---
> > V2: Fix 2 from's.
> >     Remove the unnecessary braces.
>
> I'm not sure I'd call that "From:" in the message body fixed (i.e., it
> should have been the second one, not the first one; alternatively, it
> would be fine to remove that From: line from the message body since the
> one in the message header has a value matching that SOB).
>
Sure will remove From.

>
> > diff --git a/wpa_supplicant/offchannel.c b/wpa_supplicant/offchannel.c
> > @@ -253,15 +253,9 @@ int offchannel_send_action(struct wpa_supplicant *wpa_s, unsigned int freq,
> >
> >       wpa_s->pending_action_tx_status_cb = tx_cb;
> >
> > -     if (wpa_s->pending_action_tx) {
> > -             wpa_printf(MSG_DEBUG, "Off-channel: Dropped pending Action "
> > -                        "frame TX to " MACSTR " (pending_action_tx=%p)",
> > -                        MAC2STR(wpa_s->pending_action_dst),
> > -                        wpa_s->pending_action_tx);
> > -             wpa_hexdump_buf(MSG_MSGDUMP, "Pending TX frame",
> > -                             wpa_s->pending_action_tx);
> > -             wpabuf_free(wpa_s->pending_action_tx);
> > -     }
> > +     if (wpa_s->pending_action_tx)
> > +             offchannel_send_action_done(wpa_s);
>
> As noted in your reply to this, those debug prints should not be
> removed.
>
> As far as the change to offchannel_send_action_done() is concerned, I'm
> not sure it is the correct thing to do in all cases. Why would we cancel
> Action frame TX wait or remain-on-channel if the new frame is for the
> same channel?
>
I think wpa_supplicant can start the RoC, the FSM in mac80211
will check whether to start a new or continue the old depending on
the channel and time.