staging: r8188eu: exit if beacon is not from our bss

Do not process an incoming beacon message in the OnBeacon function if the
beacon was sent by a base station other than the one to which we're
connected.

This patch does not modify the behaviour of the code. It reverts the if
condition and returns if the beacon should not be processed. This is
simpler than wrapping the entire processing into a large if clause.

Tested-by: Philipp Hortmann <philipp.g.hortmann@gmail.com> # Edimax N150
Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Link: https://lore.kernel.org/r/20221126160129.178697-8-martin@kaiser.cxSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/r8188eu/core/rtw_mlme_ext.c

@@ -569,67 +569,68 @@ static void OnBeacon(struct adapter *padapter, struct recv_frame *precv_frame)
 		return;
 	}
 
-	if (!memcmp(mgmt->bssid, get_my_bssid(&pmlmeinfo->network), ETH_ALEN)) {
-		if (pmlmeinfo->state & WIFI_FW_AUTH_NULL) {
-			/* we should update current network before auth, or some IE is wrong */
-			pbss = kmalloc(sizeof(struct wlan_bssid_ex), GFP_ATOMIC);
-			if (pbss) {
-				if (collect_bss_info(padapter, precv_frame, pbss) == _SUCCESS) {
-					update_network(&pmlmepriv->cur_network.network, pbss, padapter, true);
-					rtw_get_bcn_info(&pmlmepriv->cur_network);
-				}
-				kfree(pbss);
+	if (memcmp(mgmt->bssid, get_my_bssid(&pmlmeinfo->network), ETH_ALEN))
+		return;
+
+	if (pmlmeinfo->state & WIFI_FW_AUTH_NULL) {
+		/* we should update current network before auth, or some IE is wrong */
+		pbss = kmalloc(sizeof(struct wlan_bssid_ex), GFP_ATOMIC);
+		if (pbss) {
+			if (collect_bss_info(padapter, precv_frame, pbss) == _SUCCESS) {
+				update_network(&pmlmepriv->cur_network.network, pbss, padapter, true);
+				rtw_get_bcn_info(&pmlmepriv->cur_network);
 			}
+			kfree(pbss);
+		}
 
-			/* check the vendor of the assoc AP */
-			pmlmeinfo->assoc_AP_vendor = check_assoc_AP(pframe + sizeof(struct ieee80211_hdr_3addr), len - sizeof(struct ieee80211_hdr_3addr));
+		/* check the vendor of the assoc AP */
+		pmlmeinfo->assoc_AP_vendor = check_assoc_AP(pframe + sizeof(struct ieee80211_hdr_3addr), len - sizeof(struct ieee80211_hdr_3addr));
 
-			pmlmeext->TSFValue = le64_to_cpu(mgmt->u.beacon.timestamp);
+		pmlmeext->TSFValue = le64_to_cpu(mgmt->u.beacon.timestamp);
 
-			/* start auth */
-			start_clnt_auth(padapter);
+		/* start auth */
+		start_clnt_auth(padapter);
 
-			return;
-		}
+		return;
+	}
 
-		if (((pmlmeinfo->state & 0x03) == WIFI_FW_STATION_STATE) && (pmlmeinfo->state & WIFI_FW_ASSOC_SUCCESS)) {
-			psta = rtw_get_stainfo(pstapriv, mgmt->sa);
-			if (psta) {
-				ret = rtw_check_bcn_info(padapter, pframe, len);
-				if (!ret) {
-					receive_disconnect(padapter,
-							   pmlmeinfo->network.MacAddress, 0);
-					return;
-				}
-				/* update WMM, ERP in the beacon */
-				/* todo: the timer is used instead of the number of the beacon received */
-				if ((sta_rx_pkts(psta) & 0xf) == 0)
-					update_beacon_info(padapter, ie_ptr, ie_len, psta);
-				process_p2p_ps_ie(padapter, ie_ptr, ie_len);
+	if (((pmlmeinfo->state & 0x03) == WIFI_FW_STATION_STATE) && (pmlmeinfo->state & WIFI_FW_ASSOC_SUCCESS)) {
+		psta = rtw_get_stainfo(pstapriv, mgmt->sa);
+		if (psta) {
+			ret = rtw_check_bcn_info(padapter, pframe, len);
+			if (!ret) {
+				receive_disconnect(padapter,
+						   pmlmeinfo->network.MacAddress, 0);
+				return;
 			}
-		} else if ((pmlmeinfo->state & 0x03) == WIFI_FW_ADHOC_STATE) {
-			psta = rtw_get_stainfo(pstapriv, mgmt->sa);
-			if (psta) {
-				/* update WMM, ERP in the beacon */
-				/* todo: the timer is used instead of the number of the beacon received */
-				if ((sta_rx_pkts(psta) & 0xf) == 0)
-					update_beacon_info(padapter, ie_ptr, ie_len, psta);
-			} else {
-				/* allocate a new CAM entry for IBSS station */
-				cam_idx = allocate_fw_sta_entry(padapter);
-				if (cam_idx == NUM_STA)
-					return;
+			/* update WMM, ERP in the beacon */
+			/* todo: the timer is used instead of the number of the beacon received */
+			if ((sta_rx_pkts(psta) & 0xf) == 0)
+				update_beacon_info(padapter, ie_ptr, ie_len, psta);
+			process_p2p_ps_ie(padapter, ie_ptr, ie_len);
+		}
+	} else if ((pmlmeinfo->state & 0x03) == WIFI_FW_ADHOC_STATE) {
+		psta = rtw_get_stainfo(pstapriv, mgmt->sa);
+		if (psta) {
+			/* update WMM, ERP in the beacon */
+			/* todo: the timer is used instead of the number of the beacon received */
+			if ((sta_rx_pkts(psta) & 0xf) == 0)
+				update_beacon_info(padapter, ie_ptr, ie_len, psta);
+		} else {
+			/* allocate a new CAM entry for IBSS station */
+			cam_idx = allocate_fw_sta_entry(padapter);
+			if (cam_idx == NUM_STA)
+				return;
 
-				/* get supported rate */
-				if (update_sta_support_rate(padapter, ie_ptr, ie_len, cam_idx) == _FAIL) {
-					pmlmeinfo->FW_sta_info[cam_idx].status = 0;
-					return;
-				}
+			/* get supported rate */
+			if (update_sta_support_rate(padapter, ie_ptr, ie_len, cam_idx) == _FAIL) {
+				pmlmeinfo->FW_sta_info[cam_idx].status = 0;
+				return;
+			}
 
-				pmlmeext->TSFValue = le64_to_cpu(mgmt->u.beacon.timestamp);
+			pmlmeext->TSFValue = le64_to_cpu(mgmt->u.beacon.timestamp);
 
-				report_add_sta_event(padapter, mgmt->sa, cam_idx);
-			}
+			report_add_sta_event(padapter, mgmt->sa, cam_idx);
 		}
 	}
 }