From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.1 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1,USER_IN_DEF_DKIM_WL autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A2A66C433DF for ; Wed, 29 Jul 2020 17:17:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 806502075D for ; Wed, 29 Jul 2020 17:17:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="bIlBQZvb" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726942AbgG2RRH (ORCPT ); Wed, 29 Jul 2020 13:17:07 -0400 Received: from linux.microsoft.com ([13.77.154.182]:56742 "EHLO linux.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726365AbgG2RRG (ORCPT ); Wed, 29 Jul 2020 13:17:06 -0400 Received: from [192.168.0.104] (c-73-42-176-67.hsd1.wa.comcast.net [73.42.176.67]) by linux.microsoft.com (Postfix) with ESMTPSA id 7E58720B4908; Wed, 29 Jul 2020 10:17:06 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 7E58720B4908 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1596043026; bh=a5ZO3XwImsJ6xmCVERPzkS/M6810S100UZ5+ojy648c=; h=From:To:Cc:Subject:Date:From; b=bIlBQZvbRZzqyom4oIbGYsWUJo+yh2NSz5EFuTksM7k92nI4+pHX7biYTtMUsU/TZ K5NKZm+DPkuQPj5l5XYsAq9Mh//5zbqfy++gh77u1ZfXBDM7iOmZpnswZSb68c4MCO fUKCitoSuYa8cdsDVY6ZYAgt7n/y9fKesrYVwvBY= From: Lakshmi Ramasubramanian To: Mimi Zohar , linux-integrity@vger.kernel.org Cc: Tyler Hicks Subject: Measure data again even when it has not changed Message-ID: <8bcf778d-8fa8-9985-43d7-c2b80d8d8445@linux.microsoft.com> Date: Wed, 29 Jul 2020 10:17:05 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-integrity-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org Hi Mimi, I have a query related to measuring data (by IMA subsystem) when that data has been already been measured. Consider the following sequence of events: => At time T0 IMA hook is called by another subsystem to measure data "foo". IMA measures it. => At time T1 data is "bar". IMA measures it. => At time T2 data is "foo" again. But IMA doesn't measure it since it is already in the measured list. But for the subsystem making the call to IMA, the state has changed and "foo" has to be measured again. One way to address the above is to use unique "event name" in each call so that IMA measures the given data every time. Is there a better way to address the above? thanks, -lakshmi