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=-2.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_DBL_ABUSE_MALW,USER_AGENT_SANE_1 autolearn=no 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 DF9A4C2D0DB for ; Tue, 28 Jan 2020 21:19:23 +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 7EEF42465B for ; Tue, 28 Jan 2020 21:19:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="nKuDBIRG" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7EEF42465B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=namei.org 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:MIME-Version:References:Message-ID: In-Reply-To:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=fzU13gCxd85qfPxsa+GPoP7zc8X9qpHpAceND3ZVB+g=; b=nKuDBIRGE8iQGd YqCzAibFUgJ5jZCD9ovaZ3woRtakRCaqufGHzFc8848IOJU5pmBGeDV1MGkhtx6qpMVsUWzLNbuuK jVDE6SzX09JUYHmy2zA6gGKNzDH8SKJgqFiLV/t5ie9qZsxkhoLE0YNOe66dUSGfAWVEwpZUK6Z8g HH08Hv2nQKQMC9FsALCIotUqOO+3ztLDpvD8Xbu9XIDsKpsits8oabtmwtwU+78AqdV7bpPvOxR0e 7vKOEi3zc+Efl5U0zWDVlvtBY45jseUfM8N7HQg9o6+UOtjCLMsXq1fEEv8/onaTVSIBiKX6YRrtN yImxc+2x5Ql8XW43U3hw==; 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 1iwYGQ-0003zQ-4T; Tue, 28 Jan 2020 21:19:14 +0000 Received: from namei.org ([65.99.196.166]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1iwYGF-0003qD-Lq for linux-arm-kernel@lists.infradead.org; Tue, 28 Jan 2020 21:19:04 +0000 Received: from localhost (localhost [127.0.0.1]) by namei.org (8.14.4/8.14.4) with ESMTP id 00SLGe9n004527; Tue, 28 Jan 2020 21:16:40 GMT Date: Wed, 29 Jan 2020 08:16:40 +1100 (AEDT) From: James Morris To: Alexey Budankov Subject: Re: [PATCH v6 03/10] perf/core: open access to probes for CAP_PERFMON privileged process In-Reply-To: <6cdc10f2-31e5-6d71-7d71-c6b5250b74f1@linux.intel.com> Message-ID: References: <74d524ab-ac11-a7b8-1052-eba10f117e09@linux.intel.com> <6cdc10f2-31e5-6d71-7d71-c6b5250b74f1@linux.intel.com> User-Agent: Alpine 2.21 (LRH 202 2017-01-01) MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200128_131903_786434_7B5521F1 X-CRM114-Status: GOOD ( 10.14 ) 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: Song Liu , Peter Zijlstra , "benh@kernel.crashing.org" , Alexei Starovoitov , Lionel Landwerlin , "james.bottomley@hansenpartnership.com" , Paul Mackerras , Jiri Olsa , Andi Kleen , Michael Ellerman , Igor Lubashev , Alexander Shishkin , Ingo Molnar , oprofile-list@lists.sf.net, Serge Hallyn , Robert Richter , Will Deacon , "selinux@vger.kernel.org" , "intel-gfx@lists.freedesktop.org" , Arnaldo Carvalho de Melo , Stephane Eranian , Namhyung Kim , linux-arm-kernel , "linux-parisc@vger.kernel.org" , linux-kernel , "linux-perf-users@vger.kernel.org" , "linux-security-module@vger.kernel.org" , "linuxppc-dev@lists.ozlabs.org" 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 On Tue, 28 Jan 2020, Alexey Budankov wrote: > > Open access to monitoring via kprobes and uprobes and eBPF tracing 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. > > perf kprobes and uprobes are used by ftrace and eBPF. perf probe uses > ftrace to define new kprobe events, and those events are treated as > tracepoint events. eBPF defines new probes via perf_event_open interface > and then the probes are used in eBPF tracing. > > 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 perf_events subsystem remains > open for CAP_SYS_ADMIN privileged processes but CAP_SYS_ADMIN usage for > secure perf_events monitoring is discouraged with respect to CAP_PERFMON > capability. > > Signed-off-by: Alexey Budankov > --- > kernel/events/core.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) Acked-by: James Morris -- James Morris _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel