staging: r8188eu: stop beacon processing if kmalloc fails

If we cannot allocate a struct wlan_bssid_ex in the OnBeacon function, we
should stop processing the incoming beacon message and return.

For kmalloc failures, the current code just skips the update of network
and beacon info and tries to continue with the authentication. The update
would set the encryption algorithm that should be used for the
authentication.

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/20221126160129.178697-9-martin@kaiser.cxSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/r8188eu/core/rtw_mlme_ext.c

@@ -575,13 +575,14 @@ static void OnBeacon(struct adapter *padapter, struct recv_frame *precv_frame)
 	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 (!pbss)
+			return;
+
+		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));