From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from viti.kaiser.cx (viti.kaiser.cx [85.214.81.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E8AB02FB6 for ; Mon, 17 May 2021 20:21:57 +0000 (UTC) Received: from martin by viti.kaiser.cx with local (Exim 4.89) (envelope-from ) id 1lijkQ-0001s7-1u; Mon, 17 May 2021 22:21:54 +0200 Date: Mon, 17 May 2021 22:21:54 +0200 From: Martin Kaiser To: Christophe JAILLET Cc: Larry Finger , Greg Kroah-Hartman , Guenter Roeck , linux-staging@lists.linux.dev, kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/6] staging: rtl8188eu: use safe iterator in rtw_free_network_queue Message-ID: <20210517202154.3swbe3e2tbcjbuit@viti.kaiser.cx> References: <20210516160613.30489-1-martin@kaiser.cx> <738695eb-61f1-54b2-cd68-2143e831e338@wanadoo.fr> X-Mailing-List: linux-staging@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <738695eb-61f1-54b2-cd68-2143e831e338@wanadoo.fr> User-Agent: NeoMutt/20170113 (1.7.2) Sender: Martin Kaiser Thus wrote Christophe JAILLET (christophe.jaillet@wanadoo.fr): > Le 16/05/2021 à 18:06, Martin Kaiser a écrit : > > rtw_free_network_queue iterates over the scanned wireless networks and > > calls _rtw_free_network for each of them. In some cases, > > _rtw_free_network removes a network from the list. > > We have to use list_for_each_safe if we remove list entries while we > > iterate over a list. > > Fixes: 23017c8842d2 ("staging: rtl8188eu: Use list iterators and helpers") > > Signed-off-by: Martin Kaiser > > --- > > Without this patch, it's easy to get the driver into an endless loop by > > scanning, connecting and disconnecting repeatedly. > > wpa_supplicant -B -Dwext -i wlan0 -c /path/to/my/config... > > while true ; do > > sleep 1 > > wpa_cli reconfigure > > wpa_cli add_network > > wpa_cli set_network 0 ssid ... > > wpa_cli set_network 0 psk ... > > wpa_cli select_network 0 > > sleep 6 > > wpa_cli status > > wpa_cli disconnect 0 > > done > > drivers/staging/rtl8188eu/core/rtw_mlme.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/staging/rtl8188eu/core/rtw_mlme.c b/drivers/staging/rtl8188eu/core/rtw_mlme.c > > index 159465b073c2..14816ad51668 100644 > > --- a/drivers/staging/rtl8188eu/core/rtw_mlme.c > > +++ b/drivers/staging/rtl8188eu/core/rtw_mlme.c > > @@ -199,7 +199,7 @@ struct wlan_network *rtw_find_network(struct __queue *scanned_queue, u8 *addr) > > void rtw_free_network_queue(struct adapter *padapter, u8 isfreeall) > > { > > - struct list_head *phead, *plist; > > + struct list_head *phead, *plist, *temp; > > struct wlan_network *pnetwork; > > struct mlme_priv *pmlmepriv = &padapter->mlmepriv; > > struct __queue *scanned_queue = &pmlmepriv->scanned_queue; > > @@ -207,7 +207,7 @@ void rtw_free_network_queue(struct adapter *padapter, u8 isfreeall) > > spin_lock_bh(&scanned_queue->lock); > > phead = get_list_head(scanned_queue); > > - list_for_each(plist, phead) { > > + list_for_each_safe(plist, temp, phead) { > > pnetwork = list_entry(plist, struct wlan_network, list); > > _rtw_free_network(pmlmepriv, pnetwork, isfreeall); > Nitpicking: 'list_for_each_entry_safe' could also be used to simplify code. Thanks for the hint, I just sent out v2.