From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933407AbbHLB3r (ORCPT ); Tue, 11 Aug 2015 21:29:47 -0400 Received: from out03.mta.xmission.com ([166.70.13.233]:45049 "EHLO out03.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932755AbbHLB3q (ORCPT ); Tue, 11 Aug 2015 21:29:46 -0400 From: ebiederm@xmission.com (Eric W. Biederman) To: Oleg Nesterov Cc: "Kirill A. Shutemov" , Andrew Morton , Kees Cook , David Howells , linux-kernel@vger.kernel.org, Peter Zijlstra , Ingo Molnar , "Kirill A. Shutemov" , Rik van Riel , Vladimir Davydov , Ricky Zhou , Julien Tinnes References: <20150728171500.GA2871@www.outflux.net> <20150728143504.5aa996ba5955522a19c2d5f1@linux-foundation.org> <20150728221111.GA23391@node.dhcp.inet.fi> <20150805172356.GA20490@redhat.com> <87wpx9sjhq.fsf@x220.int.ebiederm.org> <87614tr2jd.fsf@x220.int.ebiederm.org> <20150806130629.GA4728@redhat.com> <20150806134426.GA6843@redhat.com> Date: Tue, 11 Aug 2015 20:22:57 -0500 In-Reply-To: <20150806134426.GA6843@redhat.com> (Oleg Nesterov's message of "Thu, 6 Aug 2015 15:44:26 +0200") Message-ID: <871tf9cnbi.fsf_-_@x220.int.ebiederm.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-XM-AID: U2FsdGVkX1++ZYccC3nGwX0L0oPtxyG6Sc82eKGossY= X-SA-Exim-Connect-IP: 67.3.205.173 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 * 1.5 XMNoVowels Alpha-numberic number with no vowels * 0.8 BAYES_50 BODY: Bayes spam probability is 40 to 60% * [score: 0.4965] * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa06 1397; Body=1 Fuz1=1 Fuz2=1] X-Spam-DCC: XMission; sa06 1397; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: *;Oleg Nesterov X-Spam-Relay-Country: X-Spam-Timing: total 207 ms - load_scoreonly_sql: 0.05 (0.0%), signal_user_changed: 6 (2.7%), b_tie_ro: 3.8 (1.8%), parse: 0.79 (0.4%), extract_message_metadata: 2.2 (1.1%), get_uri_detail_list: 0.59 (0.3%), tests_pri_-1000: 4.0 (1.9%), tests_pri_-950: 1.28 (0.6%), tests_pri_-900: 1.14 (0.5%), tests_pri_-400: 21 (10.1%), check_bayes: 20 (9.5%), b_tokenize: 6 (2.8%), b_tok_get_all: 6 (2.8%), b_comp_prob: 2.5 (1.2%), b_tok_touch_all: 2.9 (1.4%), b_finish: 1.03 (0.5%), tests_pri_0: 158 (76.4%), tests_pri_500: 3.6 (1.7%), rewrite_mail: 0.00 (0.0%) Subject: [PATCH 0/2] userns: Creation logic fixes 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 in02.mta.xmission.com) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org So I have take a good hard stare at the problem, as well as sitting down and writing some test code to verify the code works the way I think it does. The following two patches are how I think this bit of chaos needs to be solved. If folks could take a once over these patches and possibly test them to confirm they fix your issues I would appreciate it. Eric W. Biederman (2): unshare: Unsharing a thread does not require unsharing a vm userns,pidns: Force thread group sharing, not signal handler sharing. kernel/fork.c | 32 ++++++++++++++++++-------------- kernel/user_namespace.c | 4 ++-- 2 files changed, 20 insertions(+), 16 deletions(-) Eric