From patchwork Mon Feb 17 08:12:09 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexey Budankov X-Patchwork-Id: 11385619 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3A47214E3 for ; Mon, 17 Feb 2020 08:12:21 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (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 21AE620732 for ; Mon, 17 Feb 2020 08:12:21 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 21AE620732 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id A6FE56E516; Mon, 17 Feb 2020 08:12:20 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by gabe.freedesktop.org (Postfix) with ESMTPS id B8EF26E516 for ; Mon, 17 Feb 2020 08:12:18 +0000 (UTC) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga105.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 17 Feb 2020 00:12:18 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,451,1574150400"; d="scan'208";a="258193483" Received: from linux.intel.com ([10.54.29.200]) by fmsmga004.fm.intel.com with ESMTP; 17 Feb 2020 00:12:17 -0800 Received: from [10.125.252.180] (abudanko-mobl.ccr.corp.intel.com [10.125.252.180]) by linux.intel.com (Postfix) with ESMTP id 11B485804A2; Mon, 17 Feb 2020 00:12:10 -0800 (PST) From: Alexey Budankov To: James Morris , Serge Hallyn , Stephen Smalley , Peter Zijlstra , Arnaldo Carvalho de Melo , Ingo Molnar , "joonas.lahtinen@linux.intel.com" , Alexei Starovoitov , Will Deacon , Paul Mackerras , Helge Deller , Thomas Gleixner References: Organization: Intel Corp. Message-ID: <046beedf-e074-58e2-579d-df535799169c@linux.intel.com> Date: Mon, 17 Feb 2020 11:12:09 +0300 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.5.0 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US Subject: [Intel-gfx] [PATCH v7 10/12] drivers/oprofile: open access for CAP_PERFMON privileged process X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-man@vger.kernel.org, Andi Kleen , "linux-parisc@vger.kernel.org" , "linux-doc@vger.kernel.org" , "selinux@vger.kernel.org" , "linuxppc-dev@lists.ozlabs.org" , "intel-gfx@lists.freedesktop.org" , Igor Lubashev , linux-kernel , Stephane Eranian , "linux-security-module@vger.kernel.org" , oprofile-list@lists.sf.net, Jiri Olsa , linux-arm-kernel Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" Open access to monitoring for CAP_PERFMON privileged process. Providing the access under CAP_PERFMON capability singly, without the rest of CAP_SYS_ADMIN credentials, excludes chances to misuse the credentials and makes operation more secure. CAP_PERFMON implements the principal of least privilege for performance monitoring and observability operations (POSIX IEEE 1003.1e 2.2.2.39 principle of least privilege: A security design principle that states that a process or program be granted only those privileges (e.g., capabilities) necessary to accomplish its legitimate function, and only for the time that such privileges are actually required) For backward compatibility reasons access to the monitoring remains open for CAP_SYS_ADMIN privileged processes but CAP_SYS_ADMIN usage for secure monitoring is discouraged with respect to CAP_PERFMON capability. Signed-off-by: Alexey Budankov Reviewed-by: James Morris --- drivers/oprofile/event_buffer.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/oprofile/event_buffer.c b/drivers/oprofile/event_buffer.c index 12ea4a4ad607..6c9edc8bbc95 100644 --- a/drivers/oprofile/event_buffer.c +++ b/drivers/oprofile/event_buffer.c @@ -113,7 +113,7 @@ static int event_buffer_open(struct inode *inode, struct file *file) { int err = -EPERM; - if (!capable(CAP_SYS_ADMIN)) + if (!perfmon_capable()) return -EPERM; if (test_and_set_bit_lock(0, &buffer_opened))