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=-16.6 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL 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 8E639C43381 for ; Thu, 28 Feb 2019 23:13:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 598CD2133D for ; Thu, 28 Feb 2019 23:13:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="ghzhVGL+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728082AbfB1XNf (ORCPT ); Thu, 28 Feb 2019 18:13:35 -0500 Received: from mail-pg1-f202.google.com ([209.85.215.202]:45635 "EHLO mail-pg1-f202.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388170AbfB1XNJ (ORCPT ); Thu, 28 Feb 2019 18:13:09 -0500 Received: by mail-pg1-f202.google.com with SMTP id 17so16142084pgw.12 for ; Thu, 28 Feb 2019 15:13:09 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=Qg2yYq0hUq63hRGHhOba+WbLOFuIxBMUvDVZS8FGVBM=; b=ghzhVGL+EOOW50MsKqzFSDoDeqFyzfz4F+A809BdsxK5XLGujWuwUg7l6VN5hQdmOM vMnjgNtaM+yQpXyqcLTH9z1qhAcx9BdIaol/AXsZ6OTJgZURU7X3X9bofYed0AzAvIe3 iOjhqa7KuPAk5HzkCcMo7pZctQbBYZonfIywEB4+Gx8GydwAwweihTpX6Q2pWv9Ys26O WuwnROqSZR2utNxjtQ862ffDx3/OrT6h3myNDaQ/A5MohGfCiAWL01m9zhDgk916WZ3a O3T7FTCp9VhHNKTCm+XK6YwJKPurLXup01ex8uwUJdV3j/f9UxuS9hCM4tl/A3NX4p7t Eu3w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=Qg2yYq0hUq63hRGHhOba+WbLOFuIxBMUvDVZS8FGVBM=; b=l2jzI9yj3BUb6GYaUFJbj6uODUZGhRDaUdhm5MTiotGiGZMgosb/MEq4zrGI/MTfjB oaYcaUgQBhzoOj8S1zKU0eXFmjA5Zkjn4PRHpqJJ9APw8MKuRme7TnjAZsPpQzzDeWwE /UIbbAhyqoa3vafSpjL39VQx3r8bUAdeWOKFncYmQKN18kslPtEgzhobQbRuHYKZtqcO i3KMTwObXNsAFgEaQ4wsvn93bqD+pgyc1R59i+Jd84xlGqxANC8FoC5x8+Tt1gqNzMJZ WaCfpsoMIkBUdtuqOxomyYsj7nMiP3x8J+mw4YMGAAtL0C5KaSimk1irX53L8F3AWrbP P4rg== X-Gm-Message-State: AHQUAuYKYxsUEmjD/0rYdvd1rv42PvIj1UOoiQdwWPSpgqvv9MUnljfZ T8vGwH4RcWSJdJ4dNMUiNyAfQlIjCQ2+NR76ZDMJlQ== X-Google-Smtp-Source: APXvYqzBqqwYEj+Y8BGFwz1Y2XBzaxPlC+fblom95C6AwBCpJ8V+4s+ZQmJYnnh4F1w8vPqKp/sZq5+3o2SXE8HUmTa4mQ== X-Received: by 2002:a62:b60e:: with SMTP id j14mr975653pff.77.1551395589203; Thu, 28 Feb 2019 15:13:09 -0800 (PST) Date: Thu, 28 Feb 2019 15:12:01 -0800 In-Reply-To: <20190228231203.212359-1-matthewgarrett@google.com> Message-Id: <20190228231203.212359-25-matthewgarrett@google.com> Mime-Version: 1.0 References: <20190228231203.212359-1-matthewgarrett@google.com> X-Mailer: git-send-email 2.21.0.352.gf09ad66450-goog Subject: [PATCH 25/27] Lock down perf From: Matthew Garrett To: jmorris@namei.org Cc: linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, dhowells@redhat.com Content-Type: text/plain; charset="UTF-8" Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: From: David Howells Disallow the use of certain perf facilities that might allow userspace to access kernel data. Signed-off-by: David Howells --- kernel/events/core.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/kernel/events/core.c b/kernel/events/core.c index 26d6edab051a..4265ce43bca4 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -10477,6 +10477,11 @@ SYSCALL_DEFINE5(perf_event_open, return -EINVAL; } + if ((attr.sample_type & PERF_SAMPLE_REGS_INTR) && + kernel_is_locked_down("PERF_SAMPLE_REGS_INTR")) + /* REGS_INTR can leak data, lockdown must prevent this */ + return -EPERM; + /* Only privileged users can get physical addresses */ if ((attr.sample_type & PERF_SAMPLE_PHYS_ADDR) && perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) -- 2.21.0.352.gf09ad66450-goog