diff --git a/os_dep/linux/ioctl_cfg80211.c b/os_dep/linux/ioctl_cfg80211.c
index 83e0fe9..153f800 100755
--- a/os_dep/linux/ioctl_cfg80211.c
+++ b/os_dep/linux/ioctl_cfg80211.c
@@ -371,7 +371,7 @@ static void rtw_get_chbw_from_cfg80211_chan_def(struct cfg80211_chan_def *chdef,
 		rtw_warn_on(1);
 		*ch = 0;
 		return;
-	}		
+	}
 
 	switch (chdef->width) {
 	case NL80211_CHAN_WIDTH_20_NOHT:
@@ -1023,8 +1023,10 @@ void rtw_cfg80211_ibss_indicate_connect(_adapter *padapter)
 				return ;
 			}
 		} else {
-			if (scanned == NULL)
+			if (scanned == NULL) {
 				rtw_warn_on(1);
+				return;
+			}
 
 			if (_rtw_memcmp(&(scanned->network.Ssid), &(pnetwork->Ssid), sizeof(NDIS_802_11_SSID)) == _TRUE
 				&& _rtw_memcmp(scanned->network.MacAddress, pnetwork->MacAddress, sizeof(NDIS_802_11_MAC_ADDRESS)) == _TRUE
@@ -1288,7 +1290,7 @@ static int rtw_cfg80211_ap_set_encryption(struct net_device *dev, struct ieee_pa
 	if (is_broadcast_mac_addr(param->sta_addr)) {
 		if (param->u.crypt.idx >= WEP_KEYS
 			#ifdef CONFIG_IEEE80211W
-			&& param->u.crypt.idx > BIP_MAX_KEYID
+			|| param->u.crypt.idx > BIP_MAX_KEYID
 			#endif
 		) {
 			ret = -EINVAL;
@@ -1542,7 +1544,7 @@ static int rtw_cfg80211_set_encryption(struct net_device *dev, struct ieee_param
 	if (is_broadcast_mac_addr(param->sta_addr)) {
 		if (param->u.crypt.idx >= WEP_KEYS
 			#ifdef CONFIG_IEEE80211W
-			&& param->u.crypt.idx > BIP_MAX_KEYID
+			|| param->u.crypt.idx > BIP_MAX_KEYID
 			#endif
 		) {
 			ret = -EINVAL;
@@ -4588,8 +4590,10 @@ static int rtw_cfg80211_monitor_if_xmit_entry(struct sk_buff *skb, struct net_de
 
 	RTW_INFO(FUNC_NDEV_FMT"\n", FUNC_NDEV_ARG(ndev));
 
-	if (skb)
-		rtw_mstat_update(MSTAT_TYPE_SKB, MSTAT_ALLOC_SUCCESS, skb->truesize);
+	if (!skb)
+		goto fail;
+
+	rtw_mstat_update(MSTAT_TYPE_SKB, MSTAT_ALLOC_SUCCESS, skb->truesize);
 
 	if (IS_CH_WAITING(rfctl)) {
 		#ifdef CONFIG_DFS_MASTER
diff --git a/os_dep/linux/os_intfs.c b/os_dep/linux/os_intfs.c
index cf17d62..14d11a0 100644
--- a/os_dep/linux/os_intfs.c
+++ b/os_dep/linux/os_intfs.c
@@ -3966,7 +3966,9 @@ void rtw_ndev_destructor(struct net_device *ndev)
 	if (ndev->ieee80211_ptr)
 		rtw_mfree((u8 *)ndev->ieee80211_ptr, sizeof(struct wireless_dev));
 #endif
+#if (LINUX_VERSION_CODE < KERNEL_VERSION(4, 11, 9))
 	free_netdev(ndev);
+#endif
 }
 
 #ifdef CONFIG_ARP_KEEP_ALIVE