wifi: cfg80211: scan: skip duplicate RNR entries

There really shouldn't be duplicate entries when we give
the list to the driver, and since we already have a list
it's easy to avoid.

While at it, remove the unnecessary allocation there.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Reviewed-by: Ilan Peer <ilan.peer@intel.com>
Reviewed-by: Benjamin Berg <benjamin.berg@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://patch.msgid.link/20250101070249.b0012c70f503.Id6fcad979434c1437340aa283abae2906345cca1@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/wireless/scan.c

@@ -729,7 +729,7 @@ cfg80211_parse_colocated_ap_iter(void *_data, u8 type,
 					   bss_params)))
 		return RNR_ITER_CONTINUE;
 
-	entry = kzalloc(sizeof(*entry) + IEEE80211_MAX_SSID_LEN, GFP_ATOMIC);
+	entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
 	if (!entry)
 		return RNR_ITER_ERROR;
 
@@ -738,6 +738,17 @@ cfg80211_parse_colocated_ap_iter(void *_data, u8 type,
 
 	if (!cfg80211_parse_ap_info(entry, tbtt_info, tbtt_info_len,
 				    data->ssid_elem, data->s_ssid_tmp)) {
+		struct cfg80211_colocated_ap *tmp;
+
+		/* Don't add duplicate BSSIDs on the same channel. */
+		list_for_each_entry(tmp, &data->ap_list, list) {
+			if (ether_addr_equal(tmp->bssid, entry->bssid) &&
+			    tmp->center_freq == entry->center_freq) {
+				kfree(entry);
+				return RNR_ITER_CONTINUE;
+			}
+		}
+
 		data->n_coloc++;
 		list_add_tail(&entry->list, &data->ap_list);
 	} else {