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=-5.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,URIBL_DBL_ABUSE_MALW, USER_AGENT_SANE_1 autolearn=ham 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 AEBEDC35247 for ; Wed, 5 Feb 2020 17:36:45 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 858BD217BA for ; Wed, 5 Feb 2020 17:36:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="Xx/wJuhQ" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 858BD217BA 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=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date: Message-ID:References:To:From:Subject:Reply-To:Content-ID:Content-Description :Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=MPSd3n8fte9LImRZgj+dXquCJzGc+I+8U+Gif+V1NjM=; b=Xx/wJuhQnDKQnd ac66yTC287bsRDIY//9e0TU8UhYkM04MpbhtRxpi7O/rFFARsx7ibDviwHIWnlYV2O0NbRRGV+79U 97IdOOJb7Ml5XEe9ZICkiWQCyW/t0BJcraKzSFEyYfG8CsT+20OizG31ZYDknCHqGsCI8B1epNT2h tN1R70fy9jkINDjL5p7mL926FSN4wdF/YbIV99jvtTMCw8k8GVyjphvJP7+TP/wgmKUf8EsXy6c20 q4N+QK+++IiUajy/Dfj3tTk5oXYKFXYOGV0/L6zfsb1OlhFRautF1cR1Iye9OEynVYcspCvJMyFtz cRmayRAmMh2SXGSsHdMg==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1izObS-0005xY-90; Wed, 05 Feb 2020 17:36:42 +0000 Received: from mga11.intel.com ([192.55.52.93]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1izObP-0005wg-HA for linux-arm-kernel@lists.infradead.org; Wed, 05 Feb 2020 17:36:40 +0000 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga007.jf.intel.com ([10.7.209.58]) by fmsmga102.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 05 Feb 2020 09:36:38 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,406,1574150400"; d="scan'208";a="220171665" Received: from linux.intel.com ([10.54.29.200]) by orsmga007.jf.intel.com with ESMTP; 05 Feb 2020 09:36:38 -0800 Received: from [10.252.5.149] (abudanko-mobl.ccr.corp.intel.com [10.252.5.149]) by linux.intel.com (Postfix) with ESMTP id F2F875803E3; Wed, 5 Feb 2020 09:36:30 -0800 (PST) Subject: [PATCH v6 09/10] drivers/perf: open access for CAP_PERFMON privileged process 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 , Michael Ellerman References: <576a6141-36d4-14c0-b395-8d195892b916@linux.intel.com> Organization: Intel Corp. Message-ID: <4fa7407f-0da8-fffa-dd79-2da0429055f6@linux.intel.com> Date: Wed, 5 Feb 2020 20:36:29 +0300 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.4.2 MIME-Version: 1.0 In-Reply-To: <576a6141-36d4-14c0-b395-8d195892b916@linux.intel.com> Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200205_093639_594754_6E4DE524 X-CRM114-Status: GOOD ( 13.69 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Andi Kleen , "linux-parisc@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, Thomas Gleixner , Jiri Olsa , linux-arm-kernel Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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 --- drivers/perf/arm_spe_pmu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/perf/arm_spe_pmu.c b/drivers/perf/arm_spe_pmu.c index 4e4984a55cd1..5dff81bc3324 100644 --- a/drivers/perf/arm_spe_pmu.c +++ b/drivers/perf/arm_spe_pmu.c @@ -274,7 +274,7 @@ static u64 arm_spe_event_to_pmscr(struct perf_event *event) if (!attr->exclude_kernel) reg |= BIT(SYS_PMSCR_EL1_E1SPE_SHIFT); - if (IS_ENABLED(CONFIG_PID_IN_CONTEXTIDR) && capable(CAP_SYS_ADMIN)) + if (IS_ENABLED(CONFIG_PID_IN_CONTEXTIDR) && perfmon_capable()) reg |= BIT(SYS_PMSCR_EL1_CX_SHIFT); return reg; @@ -700,7 +700,7 @@ static int arm_spe_pmu_event_init(struct perf_event *event) return -EOPNOTSUPP; reg = arm_spe_event_to_pmscr(event); - if (!capable(CAP_SYS_ADMIN) && + if (!perfmon_capable() && (reg & (BIT(SYS_PMSCR_EL1_PA_SHIFT) | BIT(SYS_PMSCR_EL1_CX_SHIFT) | BIT(SYS_PMSCR_EL1_PCT_SHIFT)))) -- 2.20.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel