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Message-ID: <1359743405.8528.26.camel@jlt4.sipsolutions.net> (sfid-20130201_192945_370194_D9000099)
Subject: Re: [PATCH] cfg80211: fix BSS list hidden SSID lookup
From: Johannes Berg <johannes@sipsolutions.net>
To: linux-wireless@vger.kernel.org
Date: Fri, 01 Feb 2013 19:30:05 +0100
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On Fri, 2013-02-01 at 19:23 +0100, Johannes Berg wrote:
> From: Johannes Berg <johannes.berg@intel.com>
> 
> When trying to find a hidden SSID, the lookup function
> is done wrong; the code is trying to combine the two
> lookups into one, and as a consequence doesn't always
> find the entry at all. To understand this, consider a
> case where multiple BSS entries with the same channel
> and BSSID exist but have different SSID length. Then
> comparing against the probe response SSID length is
> bound to cause problems since the hidden one might be
> either zeroed out or zero-length.

Note that the bug really only matters if you have multiple hidden SSIDs
on a single BSSID, and those have different lengths. Which I think is
possible with some Cisco deployments ...

johannes