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=-5.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_MUTT 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 7D6F7C37124 for ; Tue, 22 Jan 2019 00:01:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 30FC821736 for ; Tue, 22 Jan 2019 00:01:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=mit.edu header.i=@mit.edu header.b="SrFd6+K8" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726342AbfAVABv (ORCPT ); Mon, 21 Jan 2019 19:01:51 -0500 Received: from mail-eopbgr770137.outbound.protection.outlook.com ([40.107.77.137]:1376 "EHLO NAM02-SN1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726002AbfAVABu (ORCPT ); Mon, 21 Jan 2019 19:01:50 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mit.edu; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=Uh6iNnofBHg+SfBkz90mSCOXspQU3haU5XylNk+TDyU=; b=SrFd6+K8nvelHB0JEqOaiWdq+Ww+wIhnwy9WrsVQL0U4ftn7x5gdl9H5u290EaYB9SMB0/t2QSt1pYin2ZN4/wRDU0sN9Lcak2Orn4E88ZxmL0P4bbiHj+y/3oOfNBqJOrHTdAVsp8V+x3YS7XzODQM1HlBPnrfMaozK7AiABXc= Received: from SN6PR0102CA0020.prod.exchangelabs.com (2603:10b6:805:1::33) by MWHPR01MB3215.prod.exchangelabs.com (2603:10b6:300:fa::15) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.1537.25; Tue, 22 Jan 2019 00:01:46 +0000 Received: from CO1NAM03FT059.eop-NAM03.prod.protection.outlook.com (2a01:111:f400:7e48::208) by SN6PR0102CA0020.outlook.office365.com (2603:10b6:805:1::33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.1537.27 via Frontend Transport; Tue, 22 Jan 2019 00:01:46 +0000 Authentication-Results: spf=pass (sender IP is 18.9.28.11) smtp.mailfrom=mit.edu; vger.kernel.org; dkim=none (message not signed) header.d=none;vger.kernel.org; dmarc=bestguesspass action=none header.from=mit.edu; Received-SPF: Pass (protection.outlook.com: domain of mit.edu designates 18.9.28.11 as permitted sender) receiver=protection.outlook.com; client-ip=18.9.28.11; helo=outgoing.mit.edu; Received: from outgoing.mit.edu (18.9.28.11) by CO1NAM03FT059.mail.protection.outlook.com (10.152.81.192) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.1558.11 via Frontend Transport; Tue, 22 Jan 2019 00:01:45 +0000 Received: from callcc.thunk.org (guestnat-104-133-0-100.corp.google.com [104.133.0.100] (may be forged)) (authenticated bits=0) (User authenticated as tytso@ATHENA.MIT.EDU) by outgoing.mit.edu (8.14.7/8.12.4) with ESMTP id x0M01hAX016639 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 21 Jan 2019 19:01:44 -0500 Received: by callcc.thunk.org (Postfix, from userid 15806) id E940A7A4C07; Mon, 21 Jan 2019 19:01:42 -0500 (EST) Date: Mon, 21 Jan 2019 19:01:42 -0500 From: "Theodore Y. Ts'o" To: Greg Kroah-Hartman CC: , , , Jiri Slaby Subject: Re: [PATCH] tty: ldisc: add sysctl to prevent autoloading of ldiscs Message-ID: <20190122000142.GB19379@mit.edu> Mail-Followup-To: "Theodore Y. Ts'o" , Greg Kroah-Hartman , kernel-hardening@lists.openwall.com, linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org, Jiri Slaby References: <20190121162642.GA2944@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20190121162642.GA2944@kroah.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-EOPAttributedMessage: 0 X-Forefront-Antispam-Report: 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2019 00:01:45.8275 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 4f0c8a6e-6b69-41d7-71df-08d67ffcccc9 X-MS-Exchange-CrossTenant-Id: 64afd9ba-0ecf-4acf-bc36-935f6235ba8b X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=64afd9ba-0ecf-4acf-bc36-935f6235ba8b;Ip=[18.9.28.11];Helo=[outgoing.mit.edu] X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: MWHPR01MB3215 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jan 21, 2019 at 05:26:42PM +0100, Greg Kroah-Hartman wrote: > By default, the kernel will automatically load the module of any line > dicipline that is asked for. As this sometimes isn't the safest thing > to do, provide a sysctl to disable this feature. > > By default, we set this to 'y' as that is the historical way that Linux > has worked, and we do not want to break working systems. But in the > future, perhaps this can default to 'n' to prevent this functionality. > > Signed-off-by: Greg Kroah-Hartman Reviewed-by: Theodore Ts'o