From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966102AbcA1RvB (ORCPT ); Thu, 28 Jan 2016 12:51:01 -0500 Received: from out01.mta.xmission.com ([166.70.13.231]:42487 "EHLO out01.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932657AbcA1Ru6 (ORCPT ); Thu, 28 Jan 2016 12:50:58 -0500 From: ebiederm@xmission.com (Eric W. Biederman) To: Kees Cook Cc: Andrew Morton , Al Viro , "Serge E. Hallyn" , Andy Lutomirski , "Austin S. Hemmelgarn" , Richard Weinberger , Robert =?utf-8?B?xZp3acSZY2tp?= , Dmitry Vyukov , David Howells , Kostya Serebryany , Alexander Potapenko , Eric Dumazet , Sasha Levin , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-hardening@lists.openwall.com In-Reply-To: <20160128143825.GA17383@www.outflux.net> (Kees Cook's message of "Thu, 28 Jan 2016 06:38:25 -0800") References: <20160128143825.GA17383@www.outflux.net> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.5 (gnu/linux) Date: Thu, 28 Jan 2016 11:41:17 -0600 Message-ID: <87wpqteh4y.fsf@x220.int.ebiederm.org> MIME-Version: 1.0 Content-Type: text/plain X-XM-AID: U2FsdGVkX19ApGVcL88RQru+v6XJvy66ejDE+eGSA+4= X-SA-Exim-Connect-IP: 97.121.81.63 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-Report: * -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.0 TVD_RCVD_IP Message was received from an IP address * 0.0 T_TM2_M_HEADER_IN_MSG BODY: No description available. * 0.8 BAYES_50 BODY: Bayes spam probability is 40 to 60% * [score: 0.5000] * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa04 1397; Body=1 Fuz1=1 Fuz2=1] X-Spam-DCC: XMission; sa04 1397; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: ;Kees Cook X-Spam-Relay-Country: X-Spam-Timing: total 230 ms - load_scoreonly_sql: 0.03 (0.0%), signal_user_changed: 3.1 (1.4%), b_tie_ro: 2.2 (1.0%), parse: 0.73 (0.3%), extract_message_metadata: 13 (5.7%), get_uri_detail_list: 0.98 (0.4%), tests_pri_-1000: 7 (3.0%), tests_pri_-950: 1.14 (0.5%), tests_pri_-900: 0.95 (0.4%), tests_pri_-400: 23 (9.9%), check_bayes: 22 (9.4%), b_tokenize: 6 (2.6%), b_tok_get_all: 6 (2.7%), b_comp_prob: 1.95 (0.8%), b_tok_touch_all: 4.5 (2.0%), b_finish: 0.63 (0.3%), tests_pri_0: 174 (75.8%), check_dkim_signature: 0.46 (0.2%), check_dkim_adsp: 3.0 (1.3%), tests_pri_500: 4.3 (1.9%), rewrite_mail: 0.00 (0.0%) Subject: Re: [PATCH v2] sysctl: allow CLONE_NEWUSER to be disabled X-Spam-Flag: No X-SA-Exim-Version: 4.2.1 (built Wed, 24 Sep 2014 11:00:52 -0600) X-SA-Exim-Scanned: Yes (on in01.mta.xmission.com) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Kees Cook writes: > There continue to be unexpected security exposures when users have access > to CLONE_NEWUSER. So how does this sucessfully address that issue? > For admins of systems that do not use user namespaces > and are running distro kernels with CONFIG_USER_NS enabled, there is > no way to disable CLONE_NEWUSER. This provides a way for sysadmins to > disable the feature to reduce their attack surface without needing to > rebuild their kernels. > > This is inspired by a similar restriction in Grsecurity, but adds > a sysctl. > I have already nacked this patch. Thank you for removing the broken capability in sysctl check. But this does not address any of the other issues I have raised. Nacked-by: "Eric W. Biederman" Further as far as I can tell this is just about a witch hunt. Isn't that what you call a campaign against something when the complaining party does not understand something persecutes it and does not bother to try and understand? I have already told you what kind of direction would be acceptable. I gave concrete suggests and here you are wasting our time with this patch again. Eric