From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751166AbZL1BLb (ORCPT ); Sun, 27 Dec 2009 20:11:31 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751048AbZL1BLa (ORCPT ); Sun, 27 Dec 2009 20:11:30 -0500 Received: from chilli.pcug.org.au ([203.10.76.44]:42141 "EHLO smtps.tip.net.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750935AbZL1BLa (ORCPT ); Sun, 27 Dec 2009 20:11:30 -0500 Date: Mon, 28 Dec 2009 12:11:22 +1100 From: Stephen Rothwell To: Linus Torvalds Cc: linux-kernel@vger.kernel.org, Avi Kivity Subject: Re: [PATCH] core, x86: make LIST_POISON less deadly Message-Id: <20091228121122.b1c86049.sfr@canb.auug.org.au> In-Reply-To: <1261315350-23407-1-git-send-email-avi@redhat.com> References: <1261315350-23407-1-git-send-email-avi@redhat.com> X-Mailer: Sylpheed 3.0.0beta4 (GTK+ 2.18.5; i486-pc-linux-gnu) Mime-Version: 1.0 Content-Type: multipart/signed; protocol="application/pgp-signature"; micalg="PGP-SHA1"; boundary="Signature=_Mon__28_Dec_2009_12_11_22_+1100_h3FnnYpdoyQX09sn" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --Signature=_Mon__28_Dec_2009_12_11_22_+1100_h3FnnYpdoyQX09sn Content-Type: text/plain; charset=US-ASCII Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi Linus, On Sun, 20 Dec 2009 15:22:30 +0200 Avi Kivity wrote: > > From: Avi Kivity >=20 > The list macros use LIST_POISON1 and LIST_POISON2 as undereferencable > pointers in order to trap erronous use of freed list_heads. Unfortunately > userspace can arrange for those pointers to actually be dereferencable, > potentially turning an oops to an expolit. >=20 > To avoid this allow architectures (currently x86_64 only) to override > the default values for these pointers with truly-undereferencable values. > This is easy on x86_64 as the virtual address space is large and contains > areas that cannot be mapped. >=20 > Other 64-bit architectures will likely find similar unmapped ranges. >=20 > [ingo: switch to 0xdead000000000000 as the unmapped area] > [ingo: add comments, cleanup] > [jaswinder: eliminate sparse warnings] >=20 > Acked-by: Linus Torvalds > Signed-off-by: Jaswinder Singh Rajput > Signed-off-by: Ingo Molnar > Signed-off-by: Avi Kivity The above fixed version of this patch has been in linux-next (via the tip tree) for one year minus one day. --=20 Cheers, Stephen Rothwell sfr@canb.auug.org.au http://www.canb.auug.org.au/~sfr/ --Signature=_Mon__28_Dec_2009_12_11_22_+1100_h3FnnYpdoyQX09sn Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) iEYEARECAAYFAks4BboACgkQjjKRsyhoI8z9WwCcDLEfHWQSp68hM2qJYtNR+NyE rZsAn3mhFoTQDe/XW/VWFoRKaS8uMAYH =ktrx -----END PGP SIGNATURE----- --Signature=_Mon__28_Dec_2009_12_11_22_+1100_h3FnnYpdoyQX09sn--