Re: [PATCH v2 3/6] staging: rtl8188eu: use safe iterator in expire_timeout_chk

Guenter Roeck
2021-05-17T20:33:19Z

On Mon, May 17, 2021 at 10:18:23PM +0200, Martin Kaiser wrote:
> 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: 23017c8842d2 ("staging: rtl8188eu: Use list iterators and helpers")
> Signed-off-by: Martin Kaiser <martin@kaiser.cx>

Reviewed-by: Guenter Roeck <linux@roeck-us.net>

> ---
> v2:
> - use list_for_each_entry_safe
> - update both loops (I forgot the 2nd loop in v1)
>
> drivers/staging/rtl8188eu/core/rtw_ap.c | 12 ++++--------
> 1 file changed, 4 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/staging/rtl8188eu/core/rtw_ap.c b/drivers/staging/rtl8188eu/core/rtw_ap.c
> index ca9a321c4921..6d7c96f1aa42 100644
> --- a/drivers/staging/rtl8188eu/core/rtw_ap.c
> +++ b/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;
> --
> 2.20.1
>