Return-path: Received: from xc.sipsolutions.net ([83.246.72.84]:37767 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756125AbZBDXgY (ORCPT ); Wed, 4 Feb 2009 18:36:24 -0500 Subject: Re: [PATCH RFC] mac80211: Filter scan results From: Johannes Berg To: Dan Williams Cc: Samuel Ortiz , John Linville , Reinette Chatre , linux-wireless@vger.kernel.org In-Reply-To: <1233789837.24227.19.camel@localhost.localdomain> (sfid-20090205_002533_129658_8CBEAF4A) References: <20090204150857.GA5069@sortiz.org> <1233789837.24227.19.camel@localhost.localdomain> (sfid-20090205_002533_129658_8CBEAF4A) Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=-bNSZk4ZmESHeoELVVsTa" Date: Thu, 05 Feb 2009 00:35:39 +0100 Message-Id: <1233790539.7390.23.camel@johannes.local> (sfid-20090205_003636_507974_9A252BDE) Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: --=-bNSZk4ZmESHeoELVVsTa Content-Type: text/plain Content-Transfer-Encoding: quoted-printable On Wed, 2009-02-04 at 18:23 -0500, Dan Williams wrote: > On Wed, 2009-02-04 at 16:08 +0100, Samuel Ortiz wrote: > > From: Samuel Ortiz > >=20 > > In very dense environment, the scan result buffer can get really large,= mostly > > due to the addition of proprietary IEs. iwlist fails, typically warning= about: > > "print_scanning_info: Allocation failed". wpa_supplicant fails as well,= after > > reallocating the scan result buffer several times, up to 132 Kbytes: > > [snip] > > Scan results did not fit - trying larger buffer (131072 bytes) > > ioctl[SIOCGIWSCAN]: Argument list too long > >=20 > > By adding a mac80211 module parameter, we can filter the scan results a= nd keep > > only the ones userspace currently worries about, i.e. WPA1, WPA2, WMM a= nd WPS. >=20 > A somewhat more acceptable, but still unacceptable hack would be to > figure out when the returned scan results buffer would be too large, and > automatically filter the IEs when it would be to large. Nope, that doesn't even work. You'd filter even before the app decided to no longer reallocate the scan buffer. johannes --=-bNSZk4ZmESHeoELVVsTa Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Comment: Johannes Berg (powerbook) iQIcBAABAgAGBQJJiiZEAAoJEKVg1VMiehFYxXYP/A2pTkU5cWGsWCNv1Qks3+pM DIF7eQG+sPBvXxYbk7beW0ysA75lZkj/e1RdMbl/vE1445Ol8xXUATzhX6g8ZJgc NekgqaxqjWzLtpzmr71d/gkbkqEXmbAzCji0w5dpqa99asy78Kry5NnhT2dWOU4P CLX3agIwefFy1OlDbDtGeqcbSFvTjhfL5GN8BvAdRABlcv9XjYsZpIEyzfTM6xit 1koa3iOt0rDsbVz9zmEen9Qp1ZChKMDaFFg7XgMKQdnWL4VkMZtbXbmQhHPTOWye Xz6ODtpdrLDc8/sKQFgnZ2suFnHIU5BZhNJXo/7cPTjDjIgGiLYDCJ2+fwVb2pAS unKdTnMXD5DGYSAgKuAVdfCgPCz4SRWvhiXDqYHeNIIDgoRxkyiSfQQ0TDP6kUQp r/34brym6wACJO8j6/1CycwjjshfUw308tUQWhHJnNpylY26jFopt67MXXbBYPJP Szvysog7O+lCu5KD505TFvSvoxGEIdSDQr5jPpT8Uhe3XDDCEAWmHnscfShiC/As DSw7xFMk5CIwGRwLl36Aha67NTF69uZugyUzn8VhcMc7z+GAogt3w1vjR53EsG/t Fmq99PRq+sGvdhKR951iKTf1h/jNCgkucgyYcgxh54uuZ/484WhKCNoLcksPAJyS QCx0Z4O2c1Lc53PCxTgB =bLPv -----END PGP SIGNATURE----- --=-bNSZk4ZmESHeoELVVsTa--