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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 6F383CA9EB0 for ; Sun, 3 Nov 2019 17:56:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5041B20663 for ; Sun, 3 Nov 2019 17:56:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728005AbfKCR4z (ORCPT ); Sun, 3 Nov 2019 12:56:55 -0500 Received: from outgoing-auth-1.mit.edu ([18.9.28.11]:38250 "EHLO outgoing.mit.edu" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727758AbfKCR4y (ORCPT ); Sun, 3 Nov 2019 12:56:54 -0500 Received: from callcc.thunk.org (guestnat-104-133-0-98.corp.google.com [104.133.0.98] (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 xA3HumMC028282 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Sun, 3 Nov 2019 12:56:49 -0500 Received: by callcc.thunk.org (Postfix, from userid 15806) id 23DB3420311; Sun, 3 Nov 2019 12:56:48 -0500 (EST) Date: Sun, 3 Nov 2019 12:56:48 -0500 From: "Theodore Y. Ts'o" To: Topi Miettinen Cc: Luis Chamberlain , Kees Cook , Alexey Dobriyan , "linux-kernel@vger.kernel.org" , "open list:FILESYSTEMS (VFS and infrastructure)" Subject: Re: [PATCH] Allow restricting permissions in /proc/sys Message-ID: <20191103175648.GA4603@mit.edu> References: <74a91362-247c-c749-5200-7bdce704ed9e@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <74a91362-247c-c749-5200-7bdce704ed9e@gmail.com> User-Agent: Mutt/1.12.2 (2019-09-21) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Nov 03, 2019 at 04:55:48PM +0200, Topi Miettinen wrote: > Several items in /proc/sys need not be accessible to unprivileged > tasks. Let the system administrator change the permissions, but only > to more restrictive modes than what the sysctl tables allow. > > Signed-off-by: Topi Miettinen Why should restruct the system administrator from changing the permissions to one which is more lax than what the sysctl tables? The system administrator is already very much trusted. Why should we take that discretion away from the system administrator? - Ted