diff mbox series

[wireless-next,13/15] wifi: mac80211: send extended MLD capa/ops if AP has it

Message ID 20250609213232.c9b8b3a6ca77.I1153d4283d1fbb9e5db60e7b939cc133a6345db5@changeid
State New
Headers show
Series [wireless-next,01/15] wifi: mac80211: avoid weird state in error path | expand

Commit Message

Korenblit, Miriam Rachel June 9, 2025, 6:35 p.m. UTC 
From: Johannes Berg <johannes.berg@intel.com>

Currently the code only sends extended MLD capa/ops in
strict mode, but if the AP has it then it should also
be able to parse it. There could be cases where the AP
doesn't have it but we would want to advertise it (e.g.
if the AP supports nothing but we want to have BTM.),
but given the broken deployed APs out there right now
this is the best we can do.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Reviewed-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
---
 net/mac80211/mlme.c | 54 +++++++++++++++++++++++++++++++++++++--------
 1 file changed, 45 insertions(+), 9 deletions(-)
diff mbox series

Patch

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 85f1d101fea3..d18a7a7e33c3 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -1939,14 +1939,7 @@  ieee80211_assoc_add_ml_elem(struct ieee80211_sub_if_data *sdata,
 	}
 	skb_put_data(skb, &mld_capa_ops, sizeof(mld_capa_ops));
 
-	/* Many APs have broken parsing of the extended MLD capa/ops field,
-	 * dropping (re-)association request frames or replying with association
-	 * response with a failure status if it's present. Without a clear
-	 * indication as to whether the AP supports parsing this field or not do
-	 * not include it in the common information unless strict mode is set.
-	 */
-	if (ieee80211_hw_check(&local->hw, STRICT) &&
-	    assoc_data->ext_mld_capa_ops) {
+	if (assoc_data->ext_mld_capa_ops) {
 		ml_elem->control |=
 			cpu_to_le16(IEEE80211_MLC_BASIC_PRES_EXT_MLD_CAPA_OP);
 		common->len += 2;
@@ -9353,6 +9346,39 @@  ieee80211_mgd_get_ap_ht_vht_capa(struct ieee80211_sub_if_data *sdata,
 	return err;
 }
 
+static bool
+ieee80211_mgd_assoc_bss_has_mld_ext_capa_ops(struct cfg80211_assoc_request *req)
+{
+	const struct cfg80211_bss_ies *ies;
+	struct cfg80211_bss *bss;
+	const struct element *ml;
+
+	/* not an MLO connection if link_id < 0, so irrelevant */
+	if (req->link_id < 0)
+		return false;
+
+	bss = req->links[req->link_id].bss;
+
+	guard(rcu)();
+	ies = rcu_dereference(bss->ies);
+	for_each_element_extid(ml, WLAN_EID_EXT_EHT_MULTI_LINK,
+			       ies->data, ies->len) {
+		const struct ieee80211_multi_link_elem *mle;
+
+		if (!ieee80211_mle_type_ok(ml->data + 1,
+					   IEEE80211_ML_CONTROL_TYPE_BASIC,
+					   ml->datalen - 1))
+			continue;
+
+		mle = (void *)(ml->data + 1);
+		if (mle->control & cpu_to_le16(IEEE80211_MLC_BASIC_PRES_EXT_MLD_CAPA_OP))
+			return true;
+	}
+
+	return false;
+
+}
+
 int ieee80211_mgd_assoc(struct ieee80211_sub_if_data *sdata,
 			struct cfg80211_assoc_request *req)
 {
@@ -9405,7 +9431,17 @@  int ieee80211_mgd_assoc(struct ieee80211_sub_if_data *sdata,
 	else
 		memcpy(assoc_data->ap_addr, cbss->bssid, ETH_ALEN);
 
-	assoc_data->ext_mld_capa_ops = cpu_to_le16(req->ext_mld_capa_ops);
+	/*
+	 * Many APs have broken parsing of the extended MLD capa/ops field,
+	 * dropping (re-)association request frames or replying with association
+	 * response with a failure status if it's present.
+	 * Set our value from the userspace request only in strict mode or if
+	 * the AP also had that field present.
+	 */
+	if (ieee80211_hw_check(&local->hw, STRICT) ||
+	    ieee80211_mgd_assoc_bss_has_mld_ext_capa_ops(req))
+		assoc_data->ext_mld_capa_ops =
+			cpu_to_le16(req->ext_mld_capa_ops);
 
 	if (ifmgd->associated) {
 		u8 frame_buf[IEEE80211_DEAUTH_FRAME_LEN];