From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932341AbaDVLiM (ORCPT ); Tue, 22 Apr 2014 07:38:12 -0400 Received: from mx1.redhat.com ([209.132.183.28]:18616 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755815AbaDVLiJ (ORCPT ); Tue, 22 Apr 2014 07:38:09 -0400 Message-ID: <53565491.702@redhat.com> Date: Tue, 22 Apr 2014 13:37:53 +0200 From: Florian Weimer User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.4.0 MIME-Version: 1.0 To: Boaz Harrosh , Jeff Layton , Jim Lieb CC: Andy Lutomirski , "Eric W. Biederman" , LSM List , "Serge E. Hallyn" , Kees Cook , Linux FS Devel , "Theodore Ts'o" , "linux-kernel@vger.kernel.org" , bfields@redhat.com Subject: Re: Thoughts on credential switching References: <53341D8E.80105@redhat.com> <20140327060225.4f4caa5a@ipyr.poochiereds.net> <53342258.8000304@redhat.com> <533428BF.8090007@gmail.com> In-Reply-To: <533428BF.8090007@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/27/2014 02:33 PM, Boaz Harrosh wrote: > man setuid should be saying DEPRECATED, EMULATED and SIGNAL NOT SAFE > and be done with it POSIX or no POSIX who cares? The glibc side cares, and there's also this bit: "It aims towards POSIX and Single UNIX Specification compliance.", which should be familiar. I get that POSIX doesn't do what people want here (umask and current directory handling are another story). But it hasn't really helped that some folks just said "POSIX sucks" and did their own thing, completely bypassing the system interfaces, instead of getting things fixed properly. Now we have to balance the kernel behavior, POSIX demands, glibc dirty hacks to implement the questionable POSIX behavior on top of the kernel interfaces, and more dirty hacks to work around glibc because some applications do not like it. I would really like to clean up this mess, but it's not clear to me where to start. > Please show me one user of that and declare it brain dead. Safely and demonstratively relinquishing elevated privileges. > POSIX or not it just does not have any real programming mining > at all. What do you mean with "mining" in this context? -- Florian Weimer / Red Hat Product Security Team