Return-path: Received: from mx1.redhat.com ([66.187.233.31]:39016 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751252AbYCLNsl (ORCPT ); Wed, 12 Mar 2008 09:48:41 -0400 Subject: Re: [PATCH] PS3: gelic: ignore scan info from zero SSID beacons From: Dan Williams To: Masakazu Mokuno Cc: Johannes Berg , "John W. Linville" , linux-wireless@vger.kernel.org, cbe-oss-dev@ozlabs.org, Geert Uytterhoeven , Stefan Assmann In-Reply-To: <20080312182438.0B1F.40F06B3A@sm.sony.co.jp> References: <20080312102148.0B08.40F06B3A@sm.sony.co.jp> <1205310310.6387.56.camel@johannes.berg> <20080312182438.0B1F.40F06B3A@sm.sony.co.jp> Content-Type: text/plain Date: Wed, 12 Mar 2008 09:42:31 -0400 Message-Id: <1205329351.32049.8.camel@localhost.localdomain> (sfid-20080312_134855_676007_8DA28B50) Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Wed, 2008-03-12 at 19:26 +0900, Masakazu Mokuno wrote: > On Wed, 12 Mar 2008 09:25:10 +0100 > Johannes Berg wrote: > > > > > > > Does this problem apply to probe responses as well? (Do probe > > > > responses from hidden SSID APs still exclude the SSID? I would > > > > guess not.) > > > > > > There has been a problem in parsing IEs, so if the received probe > > > responses include zero length IEs, they also suffer this bug. > > > > > > > As long as you can still associate w/ hidden SSID APs, I don't see > > > > a big problem. Even if you can't, no information for those APs is > > > > probably better than bad information, no? > > > > > > I was anxious that the userland apps or the users may get confused. Any > > > other thing harmful is not found. > > > OK, I withdraw this patch. > > > > I think John actually meant that it would be better to have the patch > > in. How does a "bad" scan result look like? > > Usually the zero length IE, the SSID element, is the first one of IE > list, all information in the successor elements is lost. What we can see > is bssid. > > The current firmware gives the following result. The Corega (00:0A:79) > AP was the one which sent zero length SSID if it was in hidden SSID mode. > > > iwlist wlan0 scanning > > wlan0 Scan completed : > > Cell 01 - Address: 00:06:25:C6:B9:A7 > > ESSID:"planexuser" > > Channel=1 > > Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 6 Mb/s; 9 Mb/s > > 11 Mb/s; 12 Mb/s; 18 Mb/s; 24 Mb/s; 36 Mb/s > > 48 Mb/s; 54 Mb/s > > Encryption key:on > > Mode:Master > > Signal level=100/100 > > IE: IEEE 802.11i/WPA2 Version 1 > > Group Cipher : CCMP > > Pairwise Ciphers (1) : CCMP > > Authentication Suites (1) : PSK > > Cell 02 - Address: 00:0A:79:A5:D2:E2 > > ESSID:"" > > Channel:0 > > Encryption key:on > > Mode:Master > > Signal level=100/100 Ewww. You're 100% correct; we certainly shouldn't be sending a scan result like this to userspace. Therefore: Acked-by: Dan Williams > > With fixed firmware: > > > wlan0 Scan completed : > > Cell 01 - Address: 00:06:25:C6:B9:A7 > > ESSID:"planexuser" > > Channel=1 > > Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 6 Mb/s; 9 Mb/s > > 11 Mb/s; 12 Mb/s; 18 Mb/s; 24 Mb/s; 36 Mb/s > > 48 Mb/s; 54 Mb/s > > Encryption key:on > > Mode:Master > > Signal level=100/100 > > IE: IEEE 802.11i/WPA2 Version 1 > > Group Cipher : CCMP > > Pairwise Ciphers (1) : CCMP > > Authentication Suites (1) : PSK > > Cell 02 - Address: 00:0A:79:A5:D2:E2 > > ESSID:"" > > Channel:1 > > Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 6 Mb/s > > 9 Mb/s; 12 Mb/s; 18 Mb/s; 24 Mb/s; 36 Mb/s > > 48 Mb/s; 54 Mb/s > > Encryption key:on > > Mode:Master > > Signal level=100/100 > > IE: IEEE 802.11i/WPA2 Version 1 > > Group Cipher : CCMP > > Pairwise Ciphers (1) : CCMP > > Authentication Suites (1) : PSK > > > >