staging: rtl8188eu: use safe iterator in expire_timeout_chk

In the first loop in expire_timeout_chk, we may call rtw_free_stainfo and
remove an entry from auth_list.

In the second loop, we may call list_del_init on our list.

Use list_for_each_entry_safe for both loops.

Fixes: 23017c88 ("staging: rtl8188eu: Use list iterators and helpers")
Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20210517201826.25150-3-martin@kaiser.cxSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/rtl8188eu/core/rtw_ap.c

@@ -164,9 +164,9 @@ static u8 chk_sta_is_alive(struct sta_info *psta)
 
 void expire_timeout_chk(struct adapter *padapter)
 {
-	struct list_head *phead, *plist;
+	struct list_head *phead;
 	u8 updated = 0;
-	struct sta_info *psta = NULL;
+	struct sta_info *psta, *temp;
 	struct sta_priv *pstapriv = &padapter->stapriv;
 	u8 chk_alive_num = 0;
 	char chk_alive_list[NUM_STA];
@@ -176,9 +176,7 @@ void expire_timeout_chk(struct adapter *padapter)
 
 	phead = &pstapriv->auth_list;
 	/* check auth_queue */
-	list_for_each(plist, phead) {
-		psta = list_entry(plist, struct sta_info, auth_list);
-
+	list_for_each_entry_safe(psta, temp, phead, auth_list) {
 		if (psta->expire_to > 0) {
 			psta->expire_to--;
 			if (psta->expire_to == 0) {
@@ -206,9 +204,7 @@ void expire_timeout_chk(struct adapter *padapter)
 
 	phead = &pstapriv->asoc_list;
 	/* check asoc_queue */
-	list_for_each(plist, phead) {
-		psta = list_entry(plist, struct sta_info, asoc_list);
-
+	list_for_each_entry_safe(psta, temp, phead, asoc_list) {
 		if (chk_sta_is_alive(psta) || !psta->expire_to) {
 			psta->expire_to = pstapriv->expire_to;
 			psta->keep_alive_trycnt = 0;