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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=unavailable 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 10E31C04AB7 for ; Tue, 14 May 2019 13:22:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E2A5D206A3 for ; Tue, 14 May 2019 13:22:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726151AbfENNWr (ORCPT ); Tue, 14 May 2019 09:22:47 -0400 Received: from lhrrgout.huawei.com ([185.176.76.210]:32938 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725854AbfENNWq (ORCPT ); Tue, 14 May 2019 09:22:46 -0400 Received: from LHREML711-CAH.china.huawei.com (unknown [172.18.7.108]) by Forcepoint Email with ESMTP id DDD84239182CBA24B421; Tue, 14 May 2019 14:22:44 +0100 (IST) Received: from [10.220.96.108] (10.220.96.108) by smtpsuk.huawei.com (10.201.108.34) with Microsoft SMTP Server (TLS) id 14.3.408.0; Tue, 14 May 2019 14:22:39 +0100 Subject: Re: [PATCH 2/3 v5] add a new template field buf to contain the buffer To: prakhar srivastava CC: , , , Mimi Zohar , , , Prakhar Srivastava References: <20190510223744.10154-1-prsriva02@gmail.com> <20190510223744.10154-3-prsriva02@gmail.com> <45344b2f-d9ea-f7df-e45f-18037e2ba5ca@huawei.com> From: Roberto Sassu Message-ID: Date: Tue, 14 May 2019 15:22:46 +0200 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.3.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.220.96.108] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 5/14/2019 7:07 AM, prakhar srivastava wrote: > On Mon, May 13, 2019 at 6:48 AM Roberto Sassu wrote: >> >> On 5/11/2019 12:37 AM, Prakhar Srivastava wrote: >>> From: Prakhar Srivastava >>> >>> The buffer(cmdline args) added to the ima log cannot be attested >>> without having the actual buffer. Thus to make the measured buffer >>> available to store/read a new ima template (buf) is added. >> >> Hi Prakhar >> >> please fix the typos. More comments below. >> >> >>> + buffer_event_data->type = IMA_XATTR_BUFFER; >>> + buffer_event_data->buf_length = size; >>> + memcpy(buffer_event_data->buf, buf, size); >>> + >>> + event_data.xattr_value = (struct evm_ima_xattr_data *)buffer_event_data; >>> + event_data.xattr_len = alloc_length; >> >> I would prefer that you introduce two new fields in the ima_event_data >> structure. You can initialize them directly with the parameters of >> process_buffer_measurement(). > I will make the edits, this will definitely save the kzalloc in this code > path. >> >> ima_write_template_field_data() will make >> a copy. >> > Since event_data->type is used to distinguish what the template field > should contain. > Removing the type and subsequent check in the template_init, > buf template fmt will result in the whole event_Data structure > being added to the log, which is not the expected output. > For buffer entries, the buf templet fmt will contains the buffer itself. The purpose of ima_event_data is to pass data to the init method of template fields. Each method takes the data it needs. If you pass event_data->buf and event_data->buf_len to ima_write_template_field_data() this should be fine. Roberto >>> + .field_show = ima_show_template_buf}, >> >> Please update Documentation/security/IMA-templates.rst > Will update the documentation. > > Thanks, > Prakhar Srivastava >> >> Thanks >> >> Roberto -- HUAWEI TECHNOLOGIES Duesseldorf GmbH, HRB 56063 Managing Director: Bo PENG, Jian LI, Yanli SHI