mac80211: Don't destroy auth data in case of anti-clogging

SAE AP may reject authentication with WLAN_STATUS_ANTI_CLOG_REQUIRED.
As the user space will immediately continue the authentication flow,
there is no need to destroy the authentication data in this case.
This saves unneeded station removal and releasing the channel.

Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20200326150855.7483996157a8.I8040a842874aaf6d209df3fc8a2acb97a0bf508b@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/mlme.c

@@ -2948,10 +2948,15 @@ static void ieee80211_rx_mgmt_auth(struct ieee80211_sub_if_data *sdata,
 	}
 
 	if (status_code != WLAN_STATUS_SUCCESS) {
+		cfg80211_rx_mlme_mgmt(sdata->dev, (u8 *)mgmt, len);
+
+		if (auth_alg == WLAN_AUTH_SAE &&
+		    status_code == WLAN_STATUS_ANTI_CLOG_REQUIRED)
+			return;
+
 		sdata_info(sdata, "%pM denied authentication (status %d)\n",
 			   mgmt->sa, status_code);
 		ieee80211_destroy_auth_data(sdata, false);
-		cfg80211_rx_mlme_mgmt(sdata->dev, (u8 *)mgmt, len);
 		event.u.mlme.status = MLME_DENIED;
 		event.u.mlme.reason = status_code;
 		drv_event_callback(sdata->local, sdata, &event);