From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andi Kleen Subject: Re: [Security] [SECURITY] Fix leaking of kernel heap addresses via /proc Date: Sun, 07 Nov 2010 22:52:22 +0100 Message-ID: <87sjzcssx5.fsf@basil.nowhere.org> References: <1289074307.3090.100.camel@Dan> <20101106234840.GD2935@thunk.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Linus Torvalds , Dan Rosenberg , "chas\@cmf.nrl.navy.mil" , "davem\@davemloft.net" , "kuznet\@ms2.inr.ac.ru" , "pekkas\@netcore.fi" , "jmorris\@namei.org" , "yoshfuji\@linux-ipv6.org" , "kaber\@trash.net" , "remi.denis-courmont\@nokia.com" , "netdev\@vger.kernel.org" , "security\@kernel.org" To: Ted Ts'o Return-path: Received: from one.firstfloor.org ([213.235.205.2]:55393 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751439Ab0KGVw2 (ORCPT ); Sun, 7 Nov 2010 16:52:28 -0500 In-Reply-To: <20101106234840.GD2935@thunk.org> (Ted Ts'o's message of "Sat, 6 Nov 2010 19:48:40 -0400") Sender: netdev-owner@vger.kernel.org List-ID: Ted Ts'o writes: > Are there any userspace programs that might be reasonably expected to > _use_ this information? If there is, we could just pick a random > number at boot time, and then XOR the heap adddress with that random > number. If any of the addresses can be guessed ever (and that is likely if it's allocated at boot) determining the random value will be trivial for everyone. -Andi -- ak@linux.intel.com -- Speaking for myself only.