From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1431314AbdDYNsa (ORCPT ); Tue, 25 Apr 2017 09:48:30 -0400 Received: from www.llwyncelyn.cymru ([82.70.14.225]:58038 "EHLO fuzix.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1429033AbdDYNsW (ORCPT ); Tue, 25 Apr 2017 09:48:22 -0400 Date: Tue, 25 Apr 2017 14:47:46 +0100 From: Alan Cox To: Matt Brown Cc: serge@hallyn.com, jmorris@namei.org, gregkh@linuxfoundation.org, jslaby@suse.com, corbet@lwn.net, keescook@chromium.org, akpm@linux-foundation.org, jannh@google.com, kernel-hardening@lists.openwall.com, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org Subject: Re: [PATCH v5 0/2] security: tty: make TIOCSTI ioctl require CAP_SYS_ADMIN Message-ID: <20170425144746.0d8721a3@lxorguk.ukuu.org.uk> In-Reply-To: <20170425041512.13189-1-matt@nmatt.com> References: <20170425041512.13189-1-matt@nmatt.com> Organization: Intel Corporation X-Mailer: Claws Mail 3.14.1 (GTK+ 2.24.31; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > There could be a few user programs that would be effected by this > change. > See: > notable programs are: agetty, csh, xemacs and tcsh > > However, I still believe that this change is worth it given that the > Kconfig defaults to n. This will be a feature that is turned on for the > same reason that people activate it when using grsecurity. Users of this > opt-in feature will realize that they are choosing security over some OS > features Only in this case they are not. If I am at the point I have the ability to send you TIOCSTI you already lost because I can just open /dev/tty to get access to my controlling tty and use write(). Alan