Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752937AbdDRE3y (ORCPT ); Tue, 18 Apr 2017 00:29:54 -0400 Received: from relay2-d.mail.gandi.net ([217.70.183.194]:53916 "EHLO relay2-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750723AbdDRE3w (ORCPT ); Tue, 18 Apr 2017 00:29:52 -0400 X-Originating-IP: 72.66.113.207 Subject: Re: [PATCH 1/4] added SECURITY_TIOCSTI_RESTRICT kernel config To: Greg KH References: <20170417060706.28674-1-matt@nmatt.com> <20170417060706.28674-2-matt@nmatt.com> <20170417065055.GA21022@kroah.com> Cc: jmorris@namei.org, akpm@linux-foundation.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-hardening@lists.openwall.com From: Matt Brown Message-ID: Date: Tue, 18 Apr 2017 00:29:19 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: <20170417065055.GA21022@kroah.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1503 Lines: 51 On 04/17/2017 02:50 AM, Greg KH wrote: > On Mon, Apr 17, 2017 at 02:07:03AM -0400, Matt Brown wrote: >> adding the kernel config SECURITY_TIOCSTI_RESTRICT in order to allow >> the user to restrict unprivileged command injection using TIOCSTI >> tty ioctls > > "unpriviledged command injection"? That sounds a bit "odd", don't you > think? > >> >> Signed-off-by: Matt Brown >> --- >> security/Kconfig | 12 ++++++++++++ >> 1 file changed, 12 insertions(+) >> >> diff --git a/security/Kconfig b/security/Kconfig >> index 3ff1bf9..d757bcb 100644 >> --- a/security/Kconfig >> +++ b/security/Kconfig >> @@ -18,6 +18,18 @@ config SECURITY_DMESG_RESTRICT >> >> If you are unsure how to answer this question, answer N. >> >> +config SECURITY_TIOCSTI_RESTRICT >> + bool "Restrict unprivileged use of tiocsti command injection" >> + default n >> + help >> + This enforces restrictions on unprivileged users injecting commands >> + into other processes in the same tty session using the TIOCSTI ioctl > > Tabs and spaces? > Sorry about that. Used the wrong vimrc for part of the Kconfig. Will fix in updated patch. > Since tty sessions are usually separated by different users, how would > they have the same one and yet need something like this? > > Also, why not put this in the tty config section? > > And finally, this patch on its own doesn't do anything :( > I will take your input, update my code, and resubmit as a single patch. > thanks, > > greg k-h >