From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on archive.lwn.net X-Spam-Level: X-Spam-Status: No, score=-6.0 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=unavailable autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by archive.lwn.net (Postfix) with ESMTP id C81167D08A for ; Thu, 7 Feb 2019 13:30:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726750AbfBGNa1 (ORCPT ); Thu, 7 Feb 2019 08:30:27 -0500 Received: from mga06.intel.com ([134.134.136.31]:41264 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726740AbfBGNa0 (ORCPT ); Thu, 7 Feb 2019 08:30:26 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by orsmga104.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 07 Feb 2019 05:30:25 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.58,344,1544515200"; d="scan'208";a="317082652" Received: from linux.intel.com ([10.54.29.200]) by fmsmga006.fm.intel.com with ESMTP; 07 Feb 2019 05:30:24 -0800 Received: from [10.125.252.152] (abudanko-mobl.ccr.corp.intel.com [10.125.252.152]) by linux.intel.com (Postfix) with ESMTP id D4CB95802E1; Thu, 7 Feb 2019 05:30:20 -0800 (PST) Subject: [PATCH v2 2/4] perf-security: document collected perf_events/Perf data categories From: Alexey Budankov To: Jonatan Corbet , Kees Cook , Thomas Gleixner , Ingo Molnar , Peter Zijlstra Cc: Jann Horn , Arnaldo Carvalho de Melo , Jiri Olsa , Namhyung Kim , Alexander Shishkin , Andi Kleen , Mark Rutland , Tvrtko Ursulin , "kernel-hardening@lists.openwall.com" , "linux-doc@vger.kernel.org" , linux-kernel References: Organization: Intel Corp. Message-ID: <6d075f2c-ada4-e56d-5bf8-d6d617b761db@linux.intel.com> Date: Thu, 7 Feb 2019 16:30:19 +0300 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.5.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org Document and categorize system and performance data into groups that can be captured by perf_events/Perf and explicitly indicate the group that can contain process sensitive data. Signed-off-by: Alexey Budankov --- Changes in v2: - applied comments on v1 --- Documentation/admin-guide/perf-security.rst | 32 +++++++++++++++++++-- 1 file changed, 30 insertions(+), 2 deletions(-) diff --git a/Documentation/admin-guide/perf-security.rst b/Documentation/admin-guide/perf-security.rst index 3915f07b9dea..e6eb7e1ee5ad 100644 --- a/Documentation/admin-guide/perf-security.rst +++ b/Documentation/admin-guide/perf-security.rst @@ -11,8 +11,34 @@ impose a considerable risk of leaking sensitive data accessed by monitored processes. The data leakage is possible both in scenarios of direct usage of perf_events system call API [2]_ and over data files generated by Perf tool user mode utility (Perf) [3]_ , [4]_ . The risk depends on the nature of data that -perf_events performance monitoring units (PMU) [2]_ collect and expose for -performance analysis. Having that said perf_events/Perf performance monitoring +perf_events performance monitoring units (PMU) [2]_ and Perf collect and expose +for performance analysis. Collected system and performance data may be split into +several categories: + +1. System hardware and software configuration data, for example: a CPU model and + its cache configuration, an amount of available memory and its topology, used + kernel and Perf versions, performance monitoring setup including experiment + time, events configuration, Perf command line parameters, etc. + +2. User and kernel module paths and their load addresses with sizes, process and + thread names with their PIDs and TIDs, timestamps for captured hardware and + software events. + +3. Content of kernel software counters (e.g., for context switches, page faults, + CPU migrations), architectural hardware performance counters (PMC) [8]_ and + machine specific registers (MSR) [9]_ that provide execution metrics for + various monitored parts of the system (e.g., memory controller (IMC), interconnect + (QPI/UPI) or peripheral (PCIe) uncore counters) without direct attribution to any + execution context state. + +4. Content of architectural execution context registers (e.g., RIP, RSP, RBP on + x86_64), process user and kernel space memory addresses and data, content of + various architectural MSRs that capture data from this category. + +Data that belong to the fourth category can potentially contain sensitive process +data. If PMUs in some monitoring modes capture values of execution context registers +or data from process memory then access to such monitoring capabilities requires +to be ordered and secured properly. So, perf_events/Perf performance monitoring is the subject for security access control management [5]_ . perf_events/Perf access control @@ -128,6 +154,8 @@ Bibliography .. [5] ``_ .. [6] ``_ .. [7] ``_ +.. [8] ``_ +.. [9] ``_ .. [11] ``_ .. [12] ``_