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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS 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 33E96C67790 for ; Fri, 27 Jul 2018 20:53:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CE36320671 for ; Fri, 27 Jul 2018 20:53:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CE36320671 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389554AbeG0WQv (ORCPT ); Fri, 27 Jul 2018 18:16:51 -0400 Received: from mail.kernel.org ([198.145.29.99]:59048 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389266AbeG0WQv (ORCPT ); Fri, 27 Jul 2018 18:16:51 -0400 Received: from gandalf.local.home (cpe-66-24-56-78.stny.res.rr.com [66.24.56.78]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 024B720647; Fri, 27 Jul 2018 20:53:12 +0000 (UTC) Date: Fri, 27 Jul 2018 16:53:11 -0400 From: Steven Rostedt To: "Theodore Y. Ts'o" Cc: Jann Horn , salyzyn@google.com, Nick Desaulniers , Golden_Miller83@protonmail.ch, Greg KH , Kees Cook , salyzyn@android.com, kernel list , Ingo Molnar , kernel-team@android.com, stable@vger.kernel.org, Kernel Hardening , Jeffrey Vander Stoep Subject: Re: [PATCH] tracing: do not leak kernel addresses Message-ID: <20180727165311.48b33a3f@gandalf.local.home> In-Reply-To: <20180727202114.GH13922@thunk.org> References: <753E9YR1QhdsPhsFoYuXCwfUzfyntDrc_A93hMUkktMi7lbh3KUZMcbfqKVWUfi15zYhuiDFant-ROa4QNV5shx74ff4hGngq2BOJDv-hq4=@protonmail.ch> <20180727094730.3a448629@gandalf.local.home> <20180727143141.4b53d554@gandalf.local.home> <20180727195416.GF13922@thunk.org> <20180727161103.797f12b7@gandalf.local.home> <20180727202114.GH13922@thunk.org> X-Mailer: Claws Mail 3.16.0 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 27 Jul 2018 16:21:14 -0400 "Theodore Y. Ts'o" wrote: > On Fri, Jul 27, 2018 at 04:11:03PM -0400, Steven Rostedt wrote: > > That said, I would assume that > > other Android utilities are using other debugfs files for system > > status and such. > > Yeah, I know we probably have lost the "debugfs is only for debugging > and has no place in a production system" battle, and we should just > move on and assume we need to completely harden all of debugfs. But > it's worth at least *asking* whether or not the use of debugfs for > Android can be avoided.... Perhaps we should have a way to disable directories in debugfs at boot? That way, people can only have what is needed. The reason I created tracefs, is because I was asked to so that tracing utilities could be enabled without bringing in all of debugfs itself. But now it appears there's more there that makes it have to be mounted. -- Steve