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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 00555C43603 for ; Wed, 18 Dec 2019 09:36:33 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B18B72176D for ; Wed, 18 Dec 2019 09:36:33 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B18B72176D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 47d8z34hSzzDqdX for ; Wed, 18 Dec 2019 20:36:31 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=linux.intel.com (client-ip=134.134.136.65; helo=mga03.intel.com; envelope-from=alexey.budankov@linux.intel.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.intel.com Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 47d8lr5Mk9zDqg9 for ; Wed, 18 Dec 2019 20:26:48 +1100 (AEDT) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga103.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 18 Dec 2019 01:26:43 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.69,329,1571727600"; d="scan'208";a="218090290" Received: from linux.intel.com ([10.54.29.200]) by orsmga003.jf.intel.com with ESMTP; 18 Dec 2019 01:26:43 -0800 Received: from [10.125.252.219] (abudanko-mobl.ccr.corp.intel.com [10.125.252.219]) by linux.intel.com (Postfix) with ESMTP id 355B35802C9; Wed, 18 Dec 2019 01:26:34 -0800 (PST) Subject: [PATCH v4 3/9] perf tool: extend Perf tool with CAP_SYS_PERFMON capability support From: Alexey Budankov To: Peter Zijlstra , Arnaldo Carvalho de Melo , Ingo Molnar , "jani.nikula@linux.intel.com" , "joonas.lahtinen@linux.intel.com" , "rodrigo.vivi@intel.com" , Alexei Starovoitov , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , "james.bottomley@hansenpartnership.com" , Serge Hallyn , James Morris , Will Deacon , Mark Rutland , Casey Schaufler , Robert Richter References: Organization: Intel Corp. Message-ID: <75aa0324-d01c-59fa-f0f3-b49bf6c53ff3@linux.intel.com> Date: Wed, 18 Dec 2019 12:26:33 +0300 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.9.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Song Liu , Alexander Shishkin , Stephane Eranian , Jiri Olsa , Andi Kleen , Igor Lubashev , oprofile-list@lists.sf.net, Kees Cook , Jann Horn , "selinux@vger.kernel.org" , "intel-gfx@lists.freedesktop.org" , Lionel Landwerlin , Namhyung Kim , Thomas Gleixner , linux-arm-kernel@lists.infradead.org, Tvrtko Ursulin , "linux-parisc@vger.kernel.org" , linux-kernel , "linux-perf-users@vger.kernel.org" , "linux-security-module@vger.kernel.org" , "bpf@vger.kernel.org" , "linuxppc-dev@lists.ozlabs.org" Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Extend error messages to mention CAP_SYS_PERFMON capability as an option to substitute CAP_SYS_ADMIN capability for secure system performance monitoring and observability operations. Make perf_event_paranoid_check() and __cmd_ftrace() to be aware of CAP_SYS_PERFMON capability. Signed-off-by: Alexey Budankov --- tools/perf/builtin-ftrace.c | 5 +++-- tools/perf/design.txt | 3 ++- tools/perf/util/cap.h | 4 ++++ tools/perf/util/evsel.c | 10 +++++----- tools/perf/util/util.c | 1 + 5 files changed, 15 insertions(+), 8 deletions(-) diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c index d5adc417a4ca..8096e9b5f4f9 100644 --- a/tools/perf/builtin-ftrace.c +++ b/tools/perf/builtin-ftrace.c @@ -284,10 +284,11 @@ static int __cmd_ftrace(struct perf_ftrace *ftrace, int argc, const char **argv) .events = POLLIN, }; - if (!perf_cap__capable(CAP_SYS_ADMIN)) { + if (!(perf_cap__capable(CAP_SYS_PERFMON) || + perf_cap__capable(CAP_SYS_ADMIN))) { pr_err("ftrace only works for %s!\n", #ifdef HAVE_LIBCAP_SUPPORT - "users with the SYS_ADMIN capability" + "users with the CAP_SYS_PERFMON or CAP_SYS_ADMIN capability" #else "root" #endif diff --git a/tools/perf/design.txt b/tools/perf/design.txt index 0453ba26cdbd..71755b3e1303 100644 --- a/tools/perf/design.txt +++ b/tools/perf/design.txt @@ -258,7 +258,8 @@ gets schedule to. Per task counters can be created by any user, for their own tasks. A 'pid == -1' and 'cpu == x' counter is a per CPU counter that counts -all events on CPU-x. Per CPU counters need CAP_SYS_ADMIN privilege. +all events on CPU-x. Per CPU counters need CAP_SYS_PERFMON or +CAP_SYS_ADMIN privilege. The 'flags' parameter is currently unused and must be zero. diff --git a/tools/perf/util/cap.h b/tools/perf/util/cap.h index 051dc590ceee..0f79fbf6638b 100644 --- a/tools/perf/util/cap.h +++ b/tools/perf/util/cap.h @@ -29,4 +29,8 @@ static inline bool perf_cap__capable(int cap __maybe_unused) #define CAP_SYSLOG 34 #endif +#ifndef CAP_SYS_PERFMON +#define CAP_SYS_PERFMON 38 +#endif + #endif /* __PERF_CAP_H */ diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c index f4dea055b080..3a46325e3702 100644 --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c @@ -2468,14 +2468,14 @@ int perf_evsel__open_strerror(struct evsel *evsel, struct target *target, "You may not have permission to collect %sstats.\n\n" "Consider tweaking /proc/sys/kernel/perf_event_paranoid,\n" "which controls use of the performance events system by\n" - "unprivileged users (without CAP_SYS_ADMIN).\n\n" + "unprivileged users (without CAP_SYS_PERFMON or CAP_SYS_ADMIN).\n\n" "The current value is %d:\n\n" " -1: Allow use of (almost) all events by all users\n" " Ignore mlock limit after perf_event_mlock_kb without CAP_IPC_LOCK\n" - ">= 0: Disallow ftrace function tracepoint by users without CAP_SYS_ADMIN\n" - " Disallow raw tracepoint access by users without CAP_SYS_ADMIN\n" - ">= 1: Disallow CPU event access by users without CAP_SYS_ADMIN\n" - ">= 2: Disallow kernel profiling by users without CAP_SYS_ADMIN\n\n" + ">= 0: Disallow ftrace function tracepoint by users without CAP_SYS_PERFMON or CAP_SYS_ADMIN\n" + " Disallow raw tracepoint access by users without CAP_SYS_PERFMON or CAP_SYS_ADMIN\n" + ">= 1: Disallow CPU event access by users without CAP_SYS_PERFMON or CAP_SYS_ADMIN\n" + ">= 2: Disallow kernel profiling by users without CAP_SYS_PERFMON or CAP_SYS_ADMIN\n\n" "To make this setting permanent, edit /etc/sysctl.conf too, e.g.:\n\n" " kernel.perf_event_paranoid = -1\n" , target->system_wide ? "system-wide " : "", diff --git a/tools/perf/util/util.c b/tools/perf/util/util.c index 969ae560dad9..9981db0d8d09 100644 --- a/tools/perf/util/util.c +++ b/tools/perf/util/util.c @@ -272,6 +272,7 @@ int perf_event_paranoid(void) bool perf_event_paranoid_check(int max_level) { return perf_cap__capable(CAP_SYS_ADMIN) || + perf_cap__capable(CAP_SYS_PERFMON) || perf_event_paranoid() <= max_level; } -- 2.20.1