From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752503Ab1KSIVN (ORCPT ); Sat, 19 Nov 2011 03:21:13 -0500 Received: from mail-bw0-f46.google.com ([209.85.214.46]:51688 "EHLO mail-bw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751252Ab1KSIVM (ORCPT ); Sat, 19 Nov 2011 03:21:12 -0500 Date: Sat, 19 Nov 2011 12:18:46 +0400 From: Vasiliy Kulikov To: Andrew Morton Cc: Pavel Emelyanov , Linux Kernel Mailing List , Cyrill Gorcunov , Glauber Costa , Andi Kleen , Tejun Heo , Matt Helsley , Pekka Enberg , Eric Dumazet , kernel-hardening@lists.openwall.com Subject: Re: [PATCH v2 0/4] Checkpoint/Restore: Show in proc IDs of objects that can be shared between tasks Message-ID: <20111119081846.GA3419@albatros> References: <4EC4DA15.7090106@parallels.com> <20111117124831.688adbeb.akpm@linux-foundation.org> <4EC6246A.6020807@parallels.com> <20111118110716.c854b4bd.akpm@linux-foundation.org> <20111119075733.GB2675@albatros> <20111119081012.GC2675@albatros> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20111119081012.GC2675@albatros> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Nov 19, 2011 at 12:10 +0400, Vasiliy Kulikov wrote: > Also, if one should have an ability to learn IDs of specific object > types and the set of types is very limited, it's much safer to have one > increasing u64 counter for each created object of one of these types. > The exposed to userspace data will be: > > ID = hash(counter ^ cookie) Even hash(counter) without any cookie and counter is randomly generated at boot time. -- Vasiliy Kulikov http://www.openwall.com - bringing security into open computing environments