From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-qk1-f180.google.com (mail-qk1-f180.google.com [209.85.222.180]) (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 F10A571 for ; Mon, 17 May 2021 20:30:19 +0000 (UTC) Received: by mail-qk1-f180.google.com with SMTP id o27so7132054qkj.9 for ; Mon, 17 May 2021 13:30:19 -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=bJtsCzAAfzfgWGG5zeNNWX1IxBdBK+YvWcZ2EEt9SEA=; b=aQ1b83W4tx2OXxhE4IBzyHZ97MmP9oc9sNW17IfhHtfOwVFPaPaYnOscDcmQD4dRXa SGoqC/kSrGKvbQRVLO+vQii4M5IGTtvrZ+RL0TyOCedfUEn/0EPSEpg+zA99u1Tsu9oW 0Ijea03MxhZQlRH2kpbucyJX8Ih7htVfc/EfbVsh2Iw4GvvqQddF7MdCyRvuQrta/MSY 5MZlAHDF1VjhhDxfYzYVlPKwiVEsUP1shAvuNhyCj34G6chMbAc1g47wCGTm8dW9PTKg +hMA5imKUP6qWZL5OwBIACduNRdFZ3Zza7BUXCaUtH510lWLLhTGzIuGszrtBkcBVjWi 1BXQ== 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=bJtsCzAAfzfgWGG5zeNNWX1IxBdBK+YvWcZ2EEt9SEA=; b=iRJy4ueO8TaFvBF7ScoO8Uw6Lf9zCUULofFAtpEt30Zr/17L+0Uq8My9eAk+ToC+O/ FXf+jCgNdDGAOw3Nv44RGRC4eoAg3IQyNo6EBkyme+rc/nM4nFobqdrGiggsm5Nwbny3 whRjGxxBnM5Pz3v8ZXZZr+G/CFhirjvQ3kTV7wkwrr2ERmlzS71QPOCPRGXpaHKq+tkL YZi6CXp0mn/zK0Wp+tJEyU5QznvBkEcv6hg6XXYI0wOj3DPqoKQJ7KaoOc6/C5x8Gjoh 4o+VS5grvd19yXRQAcQulGU0gHh1wRB+CUOZPTY5R17vk2ymW6qCACPB2GF2xjSKxtZ0 Mp4A== X-Gm-Message-State: AOAM533P62tpUdeZ5biZbkvtI/l68kguHrc/qjWsK6X1FhqpDIdjmash PhdVNzWjEIXC+/h7CFq3Yuk= X-Google-Smtp-Source: ABdhPJwC79WDTflcZNZYFsVra8+I1OYWlvLVFTCmjd4vR+cJ5UqB4Jy1j+o0qKuaa9LQEETG1RSXWg== X-Received: by 2002:a37:9e12:: with SMTP id h18mr1716835qke.483.1621283419114; Mon, 17 May 2021 13:30:19 -0700 (PDT) Received: from localhost ([2600:1700:e321:62f0:329c:23ff:fee3:9d7c]) by smtp.gmail.com with ESMTPSA id z18sm10779728qki.55.2021.05.17.13.30.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 17 May 2021 13:30:18 -0700 (PDT) Sender: Guenter Roeck Date: Mon, 17 May 2021 13:30:16 -0700 From: Guenter Roeck To: Martin Kaiser Cc: Larry Finger , Greg Kroah-Hartman , Christophe JAILLET , Dan Carpenter , linux-staging@lists.linux.dev, kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 1/6] staging: rtl8188eu: use safe iterator in rtw_free_network_queue Message-ID: <20210517203016.GA3620180@roeck-us.net> References: <20210516160613.30489-1-martin@kaiser.cx> <20210517201826.25150-1-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: <20210517201826.25150-1-martin@kaiser.cx> On Mon, May 17, 2021 at 10:18:21PM +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_entry_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 Reviewed-by: Guenter Roeck > --- > v2: > - use list_for_each_entry_safe > > 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 | 10 ++++------ > 1 file changed, 4 insertions(+), 6 deletions(-) > > diff --git a/drivers/staging/rtl8188eu/core/rtw_mlme.c b/drivers/staging/rtl8188eu/core/rtw_mlme.c > index 159465b073c2..ba73ac5325e2 100644 > --- a/drivers/staging/rtl8188eu/core/rtw_mlme.c > +++ b/drivers/staging/rtl8188eu/core/rtw_mlme.c > @@ -199,19 +199,17 @@ 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 wlan_network *pnetwork; > + struct list_head *phead; > + struct wlan_network *pnetwork, *temp; > struct mlme_priv *pmlmepriv = &padapter->mlmepriv; > struct __queue *scanned_queue = &pmlmepriv->scanned_queue; > > spin_lock_bh(&scanned_queue->lock); > > phead = get_list_head(scanned_queue); > - list_for_each(plist, phead) { > - pnetwork = list_entry(plist, struct wlan_network, list); > - > + list_for_each_entry_safe(pnetwork, temp, phead, list) > _rtw_free_network(pmlmepriv, pnetwork, isfreeall); > - } > + > spin_unlock_bh(&scanned_queue->lock); > } > > -- > 2.20.1 >