From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael Kerrisk (man-pages)" Subject: Re: [PATCH 2/2] user_namespaces.7: Update the documention to reflect the fixes for negative groups Date: Thu, 12 Feb 2015 11:11:09 +0100 Message-ID: <54DC7C3D.4040100@gmail.com> References: <52e0643bd47b1e5c65921d6e00aea1f724bb510a.1417281801.git.luto@amacapital.net> <87ppbtn4mv.fsf@x220.int.ebiederm.org> <87a92xn2io.fsf@x220.int.ebiederm.org> <87r3w8liw4.fsf@x220.int.ebiederm.org> <87iohklfvj.fsf_-_@x220.int.ebiederm.org> <87fvcok11h.fsf_-_@x220.int.ebiederm.org> <971ad3f6-90fd-4e3f-916c-8988af3c826d@email.android.com> <87wq5zf83t.fsf@x220.int.ebiederm.org> <87iohh3c9c.fsf@x220.int.ebiederm.org> <8761dh3b7k.fsf_-_@x220.int.ebiederm.org> <878uicy1r9.fsf_-_@x220.int.ebiederm.org> <87ppbo1ql4.fs f_-_@x220.int.ebiederm.org> <54CF99BF.8050401@gmail.com> <87egpwk0n3.fsf@x220.int.ebiederm.org> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <87egpwk0n3.fsf@x220.int.ebiederm.org> Sender: stable-owner@vger.kernel.org To: "Eric W. Biederman" Cc: mtk.manpages@gmail.com, Linux Containers , Josh Triplett , Andrew Morton , Kees Cook , Linux API , linux-man , "linux-kernel@vger.kernel.org" , LSM , Casey Schaufler , "Serge E. Hallyn" , Richard Weinberger , Kenton Varda , stable , Andy Lutomirski List-Id: linux-api@vger.kernel.org On 02/11/2015 03:01 PM, Eric W. Biederman wrote: > "Michael Kerrisk (man-pages)" writes: > >> Hi Eric, >> >> Ping! >> >> Cheers, >> >> Michael >> >> >> On 2 February 2015 at 16:37, Michael Kerrisk (man-pages) >> wrote: >>> Hi Eric, >>> >>> Thanks for writing this up! >>> >>> On 12/12/2014 10:54 PM, Eric W. Biederman wrote: >>>> >>>> Files with access permissions such as ---rwx---rwx give fewer >>>> permissions to their group then they do to everyone else. Which means >>>> dropping groups with setgroups(0, NULL) actually grants a process >>>> privileges. >>>> >>>> The uprivileged setting of gid_map turned out not to be safe after > ^^^^^^^^^^^ > unprivileged -- typo fix Thanks for confirming. >>>> this change. Privilege setting of gid_map can be interpreted as >>>> meaning yes it is ok to drop groups. >>> >>> I had trouble to parse that sentence (and I'd like to make sure that >>> the right sentence ends up in the commit message). Did you mean: >>> >>> "*Unprivileged* setting of gid_map can be interpreted as meaning >>> yes it is ok to drop groups" >>> ? >>> >>> Or something else? > > > I meant: Setting of gid_map with privilege has been clarified to mean > that dropping groups is ok. This allows existing programs that set > gid_map with privilege to work without changes. That is newgidmap > continues to work unchanged. Thanks. I added that text to the changelog message. Cheers, Michael -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ Linux/UNIX System Programming Training: http://man7.org/training/