From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michal Simek Subject: Re: [PATCH] dma-mapping: Add BUG_ON for uninitialized dma_ops Date: Wed, 26 Jun 2013 14:58:51 +0200 Message-ID: <51CAE58B.8040705@monstr.eu> References: <201306141636.29390.arnd@arndb.de> <1371226483.2726.19.camel@dabdike> <201306191720.47185.arnd@arndb.de> Reply-To: monstr@monstr.eu Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="----enig2KIGTFMMRSCPOBBFWCDGL" Return-path: In-Reply-To: <201306191720.47185.arnd@arndb.de> Sender: linux-kernel-owner@vger.kernel.org To: Arnd Bergmann Cc: James Bottomley , Marek Szyprowski , Bjorn Helgaas , Michal Simek , "linux-kernel@vger.kernel.org" , Linux-Arch List-Id: linux-arch.vger.kernel.org This is an OpenPGP/MIME signed message (RFC 4880 and 3156) ------enig2KIGTFMMRSCPOBBFWCDGL Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: quoted-printable On 06/19/2013 05:20 PM, Arnd Bergmann wrote: > On Friday 14 June 2013, James Bottomley wrote: >> This is the MMAP_PAGE_ZERO exploit. The original exploit relied on a >> leaky personality capability clearing mask and was fixed in 2.6.31 by >> >> commit f9fabcb58a6d26d6efde842d1703ac7cfa9427b6 >> Author: Julien Tinnes >> Date: Fri Jun 26 20:27:40 2009 +0200 >> >> personality: fix PER_CLEAR_ON_SETID >> >> So it's not really relevant to 3.x kernels, is it? >=20 > Probably not. There is always a risk that something like this > can turn into an exploit, but it needs a combination with a couple > of other bugs. ok. Let me refresh this thread. We have middle solution where some functions have this checking and some not. Based on get_maintainer scripts Arnd should do that decision to accept or reject this patch. Arnd: Can you please decide if you want it or not? Based on that you can just add this one or we can create new one which remove BUG_ON(!ops) from that file. Thanks, Michal --=20 Michal Simek, Ing. (M.Eng), OpenPGP -> KeyID: FE3D1F91 w: www.monstr.eu p: +42-0-721842854 Maintainer of Linux kernel - Microblaze cpu - http://www.monstr.eu/fdt/ Maintainer of Linux kernel - Xilinx Zynq ARM architecture Microblaze U-BOOT custodian and responsible for u-boot arm zynq platform ------enig2KIGTFMMRSCPOBBFWCDGL Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iEYEARECAAYFAlHK5YsACgkQykllyylKDCEb9wCfUf7eEr7loL10RfpNXv2PiTWm w4QAoJXx9NxrObW9GZV9r9LZSHc9zZcS =3hxx -----END PGP SIGNATURE----- ------enig2KIGTFMMRSCPOBBFWCDGL-- From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ea0-f173.google.com ([209.85.215.173]:57323 "EHLO mail-ea0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751475Ab3FZM6z (ORCPT ); Wed, 26 Jun 2013 08:58:55 -0400 Received: by mail-ea0-f173.google.com with SMTP id g15so7567214eak.4 for ; Wed, 26 Jun 2013 05:58:54 -0700 (PDT) Message-ID: <51CAE58B.8040705@monstr.eu> Date: Wed, 26 Jun 2013 14:58:51 +0200 From: Michal Simek Reply-To: monstr@monstr.eu MIME-Version: 1.0 Subject: Re: [PATCH] dma-mapping: Add BUG_ON for uninitialized dma_ops References: <201306141636.29390.arnd@arndb.de> <1371226483.2726.19.camel@dabdike> <201306191720.47185.arnd@arndb.de> In-Reply-To: <201306191720.47185.arnd@arndb.de> Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="----enig2KIGTFMMRSCPOBBFWCDGL" Sender: linux-arch-owner@vger.kernel.org List-ID: To: Arnd Bergmann Cc: James Bottomley , Marek Szyprowski , Bjorn Helgaas , Michal Simek , "linux-kernel@vger.kernel.org" , Linux-Arch Message-ID: <20130626125851.P3pfyD9ugSEKcMiUFWLGC6Jx0a_ss8QuKdqU1kIS8JI@z> This is an OpenPGP/MIME signed message (RFC 4880 and 3156) ------enig2KIGTFMMRSCPOBBFWCDGL Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: quoted-printable On 06/19/2013 05:20 PM, Arnd Bergmann wrote: > On Friday 14 June 2013, James Bottomley wrote: >> This is the MMAP_PAGE_ZERO exploit. The original exploit relied on a >> leaky personality capability clearing mask and was fixed in 2.6.31 by >> >> commit f9fabcb58a6d26d6efde842d1703ac7cfa9427b6 >> Author: Julien Tinnes >> Date: Fri Jun 26 20:27:40 2009 +0200 >> >> personality: fix PER_CLEAR_ON_SETID >> >> So it's not really relevant to 3.x kernels, is it? >=20 > Probably not. There is always a risk that something like this > can turn into an exploit, but it needs a combination with a couple > of other bugs. ok. Let me refresh this thread. We have middle solution where some functions have this checking and some not. Based on get_maintainer scripts Arnd should do that decision to accept or reject this patch. Arnd: Can you please decide if you want it or not? Based on that you can just add this one or we can create new one which remove BUG_ON(!ops) from that file. Thanks, Michal --=20 Michal Simek, Ing. (M.Eng), OpenPGP -> KeyID: FE3D1F91 w: www.monstr.eu p: +42-0-721842854 Maintainer of Linux kernel - Microblaze cpu - http://www.monstr.eu/fdt/ Maintainer of Linux kernel - Xilinx Zynq ARM architecture Microblaze U-BOOT custodian and responsible for u-boot arm zynq platform ------enig2KIGTFMMRSCPOBBFWCDGL Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iEYEARECAAYFAlHK5YsACgkQykllyylKDCEb9wCfUf7eEr7loL10RfpNXv2PiTWm w4QAoJXx9NxrObW9GZV9r9LZSHc9zZcS =3hxx -----END PGP SIGNATURE----- ------enig2KIGTFMMRSCPOBBFWCDGL--