Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755412AbcDLAdI (ORCPT ); Mon, 11 Apr 2016 20:33:08 -0400 Received: from out02.mta.xmission.com ([166.70.13.232]:46317 "EHLO out02.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753998AbcDLAdG (ORCPT ); Mon, 11 Apr 2016 20:33:06 -0400 From: ebiederm@xmission.com (Eric W. Biederman) To: Linus Torvalds Cc: Andy Lutomirski , security@debian.org, "security\@kernel.org" , Al Viro , "security\@ubuntu.com \>\> security" , Peter Hurley , Serge Hallyn , Willy Tarreau , Aurelien Jarno , One Thousand Gnomes , Jann Horn , Greg KH , Linux Kernel Mailing List , Jiri Slaby , Florian Weimer , "H. Peter Anvin" References: <878u0s3orx.fsf_-_@x220.int.ebiederm.org> <1459819769-30387-1-git-send-email-ebiederm@xmission.com> <87twjcorwg.fsf@x220.int.ebiederm.org> <20160409140909.42315e6d@lxorguk.ukuu.org.uk> <83FE8CD2-C0A2-4ADB-AEBD-8DD89AD4F88A@zytor.com> <87bn5ij0x1.fsf@x220.int.ebiederm.org> <78205895-E11D-417F-91DC-4BCA0B61A122@zytor.com> <87ziszd7uv.fsf@x220.int.ebiederm.org> Date: Mon, 11 Apr 2016 19:22:15 -0500 In-Reply-To: (Linus Torvalds's message of "Mon, 11 Apr 2016 17:08:25 -0700") Message-ID: <87r3ebad6w.fsf@x220.int.ebiederm.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.5 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-XM-AID: U2FsdGVkX18oUwyY69TRPDBdBdqhKCvAd1XEz8qA9ds= X-SA-Exim-Connect-IP: 67.3.249.252 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-Report: * -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.7 XMSubLong Long Subject * 1.5 XMNoVowels Alpha-numberic number with no vowels * 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 * [sa01 1397; Body=1 Fuz1=1 Fuz2=1] X-Spam-DCC: XMission; sa01 1397; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: **;Linus Torvalds X-Spam-Relay-Country: X-Spam-Timing: total 4661 ms - load_scoreonly_sql: 0.06 (0.0%), signal_user_changed: 4.1 (0.1%), b_tie_ro: 2.8 (0.1%), parse: 1.27 (0.0%), extract_message_metadata: 29 (0.6%), get_uri_detail_list: 1.90 (0.0%), tests_pri_-1000: 14 (0.3%), tests_pri_-950: 1.96 (0.0%), tests_pri_-900: 1.67 (0.0%), tests_pri_-400: 33 (0.7%), check_bayes: 31 (0.7%), b_tokenize: 13 (0.3%), b_tok_get_all: 8 (0.2%), b_comp_prob: 3.9 (0.1%), b_tok_touch_all: 2.6 (0.1%), b_finish: 0.81 (0.0%), tests_pri_0: 4565 (97.9%), check_dkim_signature: 0.89 (0.0%), check_dkim_adsp: 4.1 (0.1%), tests_pri_500: 6 (0.1%), rewrite_mail: 0.00 (0.0%) Subject: Re: [PATCH 01/13] devpts: Teach /dev/ptmx to find the associated devpts via path lookup 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 Content-Length: 1136 Lines: 29 Linus Torvalds writes: > On Mon, Apr 11, 2016 at 4:49 PM, Eric W. Biederman > wrote: >> >> I replied earlier. Did you not see my reply? > > > Are you talking about the one where you agreed that the scenario was > made up and insane? The one where you said that you're worried about > breaking out "extension" where ptmx is non-0666? I meant the one where I conceded that the only think that it could possible protect against was a denial of service attack, from which we probably don't care. I just want to be certain that the emails are getting through. As the meaning certainly has not been. I do think I called a permision check in posix_open aka on /dev/ptmx a linux specific extension in that email. But seriously it was all about reducing the scope of the change. Reducing the size of the test matrix. I simply had not looked far enough to see if there was anything you could reasonable protect with those permissions. As I agreed with you that it was unnecessary I was just puzzled why you called what was essentially agreement with you deafening silence. Eric