From patchwork Thu Apr 2 08:53:07 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexey Budankov X-Patchwork-Id: 11470351 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 B650A81 for ; Thu, 2 Apr 2020 08:53:17 +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 9E2DB208FE for ; Thu, 2 Apr 2020 08:53:17 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9E2DB208FE 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 349006EA1A; Thu, 2 Apr 2020 08:53:17 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTPS id F26A26EA1A for ; Thu, 2 Apr 2020 08:53:15 +0000 (UTC) IronPort-SDR: 2t9a8KYzlbYRrhFlFDYs/7oImT1zpKNvocoGOKiNdC+mN8Tt8uY8B9fAydbjGrFialfYeexvVN 91CgyNpBgYYw== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Apr 2020 01:53:15 -0700 IronPort-SDR: 0d09LmQxjwdOTwQhwodxomnqmvwvXp3uLhsrsNBHN8aidh3hD0dbxAdS3Rx/o5gXv7RdtTYUV/ 78nLAMk/cjvw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.72,335,1580803200"; d="scan'208";a="243005477" Received: from linux.intel.com ([10.54.29.200]) by orsmga008.jf.intel.com with ESMTP; 02 Apr 2020 01:53:15 -0700 Received: from [10.249.226.252] (abudanko-mobl.ccr.corp.intel.com [10.249.226.252]) by linux.intel.com (Postfix) with ESMTP id 6FA66580544; Thu, 2 Apr 2020 01:53:08 -0700 (PDT) From: Alexey Budankov To: Peter Zijlstra , Arnaldo Carvalho de Melo , Alexei Starovoitov , Ingo Molnar , James Morris , Namhyung Kim References: Organization: Intel Corp. Message-ID: <691f1096-b15f-9b12-50a0-c2b93918149e@linux.intel.com> Date: Thu, 2 Apr 2020 11:53:07 +0300 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.6.0 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US Subject: [Intel-gfx] [PATCH v8 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, Song Liu , Andi Kleen , "linux-doc@vger.kernel.org" , "selinux@vger.kernel.org" , "intel-gfx@lists.freedesktop.org" , Igor Lubashev , linux-kernel , Stephane Eranian , "linux-security-module@vger.kernel.org" , Thomas Gleixner , Jiri Olsa , Serge Hallyn 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 Acked-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))