From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751496AbbCIXqk (ORCPT ); Mon, 9 Mar 2015 19:46:40 -0400 Received: from out01.mta.xmission.com ([166.70.13.231]:38539 "EHLO out01.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751105AbbCIXqj (ORCPT ); Mon, 9 Mar 2015 19:46:39 -0400 From: ebiederm@xmission.com (Eric W. Biederman) To: Kees Cook Cc: Dave Hansen , Andrew Morton , "Theodore Ts'o" , Oleg Nesterov , LKML , Dave Hansen References: <20150309204321.AAF412E0@viggo.jf.intel.com> <878uf5vmxo.fsf@x220.int.ebiederm.org> <87h9ttrcpr.fsf@x220.int.ebiederm.org> Date: Mon, 09 Mar 2015 18:43:00 -0500 In-Reply-To: <87h9ttrcpr.fsf@x220.int.ebiederm.org> (Eric W. Biederman's message of "Mon, 09 Mar 2015 18:08:16 -0500") Message-ID: <878uf5rb3v.fsf@x220.int.ebiederm.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-XM-AID: U2FsdGVkX19/UmbwBtvQtAWEslgIvZhStPGPxWlj7pA= X-SA-Exim-Connect-IP: 70.59.163.10 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-Report: * -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.0 TVD_RCVD_IP Message was received from an IP address * 1.5 TR_Symld_Words too many words that have symbols inside * 1.5 XMNoVowels Alpha-numberic number with no vowels * 0.7 XMSubLong Long Subject * 0.0 T_TM2_M_HEADER_IN_MSG BODY: No description available. * 0.8 BAYES_50 BODY: Bayes spam probability is 40 to 60% * [score: 0.5000] * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa05 1397; Body=1 Fuz1=1 Fuz2=1] X-Spam-DCC: XMission; sa05 1397; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: ***;Kees Cook X-Spam-Relay-Country: X-Spam-Timing: total 109 ms - load_scoreonly_sql: 0.05 (0.0%), signal_user_changed: 3.0 (2.7%), b_tie_ro: 2.1 (1.9%), parse: 0.61 (0.6%), extract_message_metadata: 1.72 (1.6%), get_uri_detail_list: 0.25 (0.2%), tests_pri_-1000: 3.1 (2.8%), tests_pri_-950: 1.10 (1.0%), tests_pri_-900: 0.91 (0.8%), tests_pri_-400: 13 (11.9%), check_bayes: 12 (11.1%), b_tokenize: 3.0 (2.8%), b_tok_get_all: 3.8 (3.5%), b_comp_prob: 1.21 (1.1%), b_tok_touch_all: 2.4 (2.2%), b_finish: 0.57 (0.5%), tests_pri_0: 74 (68.1%), tests_pri_500: 3.4 (3.1%), rewrite_mail: 0.00 (0.0%) Subject: Re: [RFC][PATCH 1/2] fs proc: make pagemap a privileged interface X-Spam-Flag: No X-SA-Exim-Version: 4.2.1 (built Wed, 24 Sep 2014 11:00:52 -0600) X-SA-Exim-Scanned: Yes (on in01.mta.xmission.com) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org A 1 to 1 blinding function like integer multiplication mudulo 2^32 by an appropriate random number ought to keep from revealing page numbers or page ajacencies while not requiring any changes in userspace. That way the revealed pfn and the physcial pfn would be different but you could still use pagemap for it's intended purpose. Eric