From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-qt1-f180.google.com (mail-qt1-f180.google.com [209.85.160.180]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8C50D2FB0 for ; Sun, 16 May 2021 19:24:10 +0000 (UTC) Received: by mail-qt1-f180.google.com with SMTP id j11so3423989qtn.12 for ; Sun, 16 May 2021 12:24:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=fZxwgKfIQimb2AFH9JXSBKvKMRan0cAJtKbrTFd8DCw=; b=oAFuw8Wmvx0yY/70GlCle9lO76HkGhbMJymOixmBUvyzzqQT0FOomMm56cDB73Rd5g t4zw3VSbnD//3Ew+RisP/Dy8OWP24iNKZTqgt0VdIjmuF46hpwRwCa6pFa7YxgaU1xo8 1KyLY+bFS6eBYBQzDT5vI0sRjLFzgTg0bJtFBchVtxQKg1LRPV8+JcPiiYUfyIdibnAI /wnf6FonMZ1G/hOypvchbLwy/sHTeKUDE4GwBy7g+pwKTED4yjLEPFw/5hPIsao/ZNSe F2/IPPW+X3FGPaeBWtoK9IvlmGjTZiPx4jZCyjUJlkqxvqDgW5htN4TcSaIpn5TUHTmj XBJw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to; bh=fZxwgKfIQimb2AFH9JXSBKvKMRan0cAJtKbrTFd8DCw=; b=td6TnmaI2x2fje1geRs5Loocvj+Mjx4ZguzP+Xb5N4CbMTYP+OdlTh0k6/O1oBKxuW GWiMmSMoVvQZd76LRkdf5zSHpOoZ/d/OQxbwgWNVPL91EjDothpB3FlJIfcSxpqTo7+Z 5rICmdPd/TZQSlwPoAj+0KDa5ktHc6FmNYA1dYt8dBZ9gszGhzkgT8q1RomWZxnaRKzO pO9eN7FbU9LwEDgFnOYirhFK4WVP7Md/oI1UPE90cL5p4IdYyFnRx59PVQ6P5k38dUXT kyLXO9dTlAgwYMKevT55cvLclOvPLNwBmkvhCGGGduy0sPuqNIIY6lqToa3wvIp8rej/ TRcA== X-Gm-Message-State: AOAM532IB9DG8ksumIEkIzkYtwr5dturcNpnmc30zrnk/2q9sFhLB5m5 4moBTSb0HUiYNIHGqoQybaU= X-Google-Smtp-Source: ABdhPJw4ToR7cX6GwzJbqm5gAAoq9uNgPrbSZky7o6MUT6XFMq14WKNkqN9PXv1mbajcZYIUonTbcg== X-Received: by 2002:ac8:5751:: with SMTP id 17mr36207643qtx.389.1621193049615; Sun, 16 May 2021 12:24:09 -0700 (PDT) Received: from localhost ([2600:1700:e321:62f0:329c:23ff:fee3:9d7c]) by smtp.gmail.com with ESMTPSA id h8sm9027603qtp.46.2021.05.16.12.24.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 16 May 2021 12:24:08 -0700 (PDT) Sender: Guenter Roeck Date: Sun, 16 May 2021 12:24:07 -0700 From: Guenter Roeck To: Martin Kaiser Cc: Larry Finger , Greg Kroah-Hartman , 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: <20210516192407.GA2126643@roeck-us.net> References: <20210516160613.30489-1-martin@kaiser.cx> X-Mailing-List: linux-staging@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210516160613.30489-1-martin@kaiser.cx> On Sun, May 16, 2021 at 06:06:08PM +0200, Martin Kaiser wrote: > 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. > Oops. Good catch. Thanks for noticing. Reviewed-by: Guenter Roeck > 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); > -- > 2.20.1 >