pbuf = vzalloc(MAX_BSS_CNT * (sizeof(struct wlan_network)));
 
-       if (pbuf == NULL) {
+       if (!pbuf) {
                res = _FAIL;
                goto exit;
        }
        u32 lifetime = SCANQUEUE_LIFETIME;
        struct __queue *free_queue = &(pmlmepriv->free_bss_pool);
 
-       if (pnetwork == NULL)
+       if (!pnetwork)
                return;
 
        if (pnetwork->fixed)
 {
        struct __queue *free_queue = &(pmlmepriv->free_bss_pool);
 
-       if (pnetwork == NULL)
+       if (!pnetwork)
                return;
        if (pnetwork->fixed)
                return;
                pwlan = container_of(plist, struct wlan_network, list);
 
                if (!pwlan->fixed) {
-                       if (oldest == NULL || time_after(oldest->last_scanned, pwlan->last_scanned))
+                       if (!oldest || time_after(oldest->last_scanned, pwlan->last_scanned))
                                oldest = pwlan;
                }
        }
 
                        pnetwork = rtw_alloc_network(pmlmepriv); /*  will update scan_time */
 
-                       if (pnetwork == NULL) {
+                       if (!pnetwork) {
                                RT_TRACE(_module_rtl871x_mlme_c_, _drv_err_, ("\n\n\nsomething wrong here\n\n\n"));
                                goto exit;
                        }
        privacy = pnetwork->network.Privacy;
 
        if (check_fwstate(pmlmepriv, WIFI_UNDER_WPS)) {
-               if (rtw_get_wps_ie(pnetwork->network.IEs+_FIXED_IE_LENGTH_, pnetwork->network.IELength-_FIXED_IE_LENGTH_, NULL, &wps_ielen) != NULL)
+               if (!rtw_get_wps_ie(pnetwork->network.IEs+_FIXED_IE_LENGTH_, pnetwork->network.IELength-_FIXED_IE_LENGTH_, NULL, &wps_ielen))
                        return true;
                else
                        return false;
        struct sta_priv *pstapriv = &padapter->stapriv;
 
        psta = rtw_get_stainfo(pstapriv, pnetwork->network.MacAddress);
-       if (psta == NULL)
+       if (!psta)
                psta = rtw_alloc_stainfo(pstapriv, pnetwork->network.MacAddress);
 
        if (psta) { /* update ptarget_sta */
                        /* s3. find ptarget_sta & update ptarget_sta after update cur_network only for station mode */
                        if (check_fwstate(pmlmepriv, WIFI_STATION_STATE) == true) {
                                ptarget_sta = rtw_joinbss_update_stainfo(adapter, pnetwork);
-                               if (ptarget_sta == NULL) {
+                               if (!ptarget_sta) {
                                        RT_TRACE(_module_rtl871x_mlme_c_, _drv_err_, ("Can't update stainfo when joinbss_event callback\n"));
                                        spin_unlock_bh(&pmlmepriv->scanned_queue.lock);
                                        goto ignore_joinbss_callback;
 #if defined(CONFIG_88EU_AP_MODE)
        if (check_fwstate(pmlmepriv, WIFI_AP_STATE)) {
                for (aid = (pstapriv->max_num_sta); aid > 0; aid--) {
-                       if (pstapriv->sta_aid[aid-1] != NULL)
+                       if (!pstapriv->sta_aid[aid-1])
                                break;
                }
                mac_id = aid + 1;
        u16 media_status;
        u8 macid;
 
-       if (psta == NULL)
+       if (!psta)
                return;
 
        macid = search_max_mac_id(adapter);
 #endif
        /* for AD-HOC mode */
        psta = rtw_get_stainfo(&adapter->stapriv, pstassoc->macaddr);
-       if (psta != NULL) {
+       if (!psta) {
                /* the sta have been in sta_info_queue => do nothing */
                RT_TRACE(_module_rtl871x_mlme_c_, _drv_err_, ("Error: rtw_stassoc_event_callback: sta has been in sta_hash_queue\n"));
                return; /* between drv has received this event before and  fw have not yet to set key to CAM_ENTRY) */
        }
        psta = rtw_alloc_stainfo(&adapter->stapriv, pstassoc->macaddr);
-       if (psta == NULL) {
+       if (!psta) {
                RT_TRACE(_module_rtl871x_mlme_c_, _drv_err_, ("Can't alloc sta_info when rtw_stassoc_event_callback\n"));
                return;
        }
                pmlmepriv->pscanned = pmlmepriv->pscanned->next;
                rtw_check_join_candidate(pmlmepriv, &candidate, pnetwork);
        }
-       if (candidate == NULL) {
+       if (!candidate) {
                DBG_88E("%s: return _FAIL(candidate==NULL)\n", __func__);
                ret = _FAIL;
                goto exit;
        else
                psta = rtw_get_stainfo(&padapter->stapriv, pattrib->ra);
 
-       if (psta == NULL)
+       if (!psta)
                return;
 
        phtpriv = &psta->htpriv;
 
        struct wlan_network *pnetwork;
 
-       if (tgt_network != NULL)
+       if (!tgt_network)
                pnetwork = tgt_network;
        else
                pnetwork = &pmlmepriv->cur_network;