Commit 2fb5dfe1 authored by Johannes Berg's avatar Johannes Berg
Browse files

wifi: mac80211: mlme: re-parse if AP mode is less than client 



If the AP mode ends up being determined less than the client mode,
there may be different reasons for this, e.g. AP misconfiguration.
If this happens in a way that causes e.g. EHT to be rejected, the
elements need to be re-parsed since we'll connect as HE, but not
reparsing means that we'll still think it's OK to use multi-link,
so we can connect in a non-sensical configuration of advertising
only HE on a secondary link. This normally won't happen for the
assoc link because that reuses the mode from authentication, and
if that's not EHT, multi-link association is rejected.

Fix this inconsistency by parsing the elements again if the mode
was different from the first parsing attempt. Print the message a
bit later to avoid printing "determined AP ... to be HE" twice in
cases where ieee80211_determine_ap_chan() returned a lesser mode,
rather than the regulatory downgrades below changing it.

Fixes: 310c8387 ("wifi: mac80211: clean up connection process")
Reviewed-by: default avatarMiriam Rachel Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://msgid.link/20240418105220.d1f25d92cfe7.Ia21eff6cdcae2f5aca13cf8e742a986af5e70f89@changeid


Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
parent 1ac6f60a

net/mac80211/mlme.c

+9 −4
Original line number Diff line number Diff line
@@ -632,15 +632,21 @@ ieee80211_determine_chan_mode(struct ieee80211_sub_if_data *sdata, 
	ap_mode = ieee80211_determine_ap_chan(sdata, channel, bss->vht_cap_info,

					      elems, false, conn, &ap_chandef);



	mlme_link_id_dbg(sdata, link_id, "determined AP %pM to be %s\n",

			 cbss->bssid, ieee80211_conn_mode_str(ap_mode));



	/* this should be impossible since parsing depends on our mode */

	if (WARN_ON(ap_mode > conn->mode)) {

		ret = -EINVAL;

		goto free;

	}



	if (conn->mode != ap_mode) {

		conn->mode = ap_mode;

		kfree(elems);

		goto again;

	}



	mlme_link_id_dbg(sdata, link_id, "determined AP %pM to be %s\n",

			 cbss->bssid, ieee80211_conn_mode_str(ap_mode));



	sband = sdata->local->hw.wiphy->bands[channel->band];



	switch (channel->band) {
@@ -691,7 +697,6 @@ ieee80211_determine_chan_mode(struct ieee80211_sub_if_data *sdata, 
		break;

	}



	conn->mode = ap_mode;

	chanreq->oper = ap_chandef;



	/* wider-bandwidth OFDMA is only done in EHT */