linux-kernel - Re: Removing Mandatory Locks

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <8ba92aa3e97bfc3df89cd64fffcbc91b640530f1.camel@kernel.org>
Date:   Thu, 19 Aug 2021 15:18:15 -0400
From:   Jeff Layton <jlayton@...nel.org>
To:     Rodrigo Campos <rodrigo@...volk.io>,
        "Eric W. Biederman" <ebiederm@...ssion.com>
Cc:     Matthew Wilcox <willy@...radead.org>,
        Andy Lutomirski <luto@...nel.org>,
        Linus Torvalds <torvalds@...ux-foundation.org>,
        David Laight <David.Laight@...lab.com>,
        David Hildenbrand <david@...hat.com>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>,
        "H. Peter Anvin" <hpa@...or.com>,
        Al Viro <viro@...iv.linux.org.uk>,
        Alexey Dobriyan <adobriyan@...il.com>,
        Steven Rostedt <rostedt@...dmis.org>,
        "Peter Zijlstra (Intel)" <peterz@...radead.org>,
        Arnaldo Carvalho de Melo <acme@...nel.org>,
        Mark Rutland <mark.rutland@....com>,
        Alexander Shishkin <alexander.shishkin@...ux.intel.com>,
        Jiri Olsa <jolsa@...hat.com>,
        Namhyung Kim <namhyung@...nel.org>,
        Petr Mladek <pmladek@...e.com>,
        Sergey Senozhatsky <sergey.senozhatsky@...il.com>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Rasmus Villemoes <linux@...musvillemoes.dk>,
        Kees Cook <keescook@...omium.org>,
        Greg Ungerer <gerg@...ux-m68k.org>,
        Geert Uytterhoeven <geert@...ux-m68k.org>,
        Mike Rapoport <rppt@...nel.org>,
        Vlastimil Babka <vbabka@...e.cz>,
        Vincenzo Frascino <vincenzo.frascino@....com>,
        Chinwen Chang <chinwen.chang@...iatek.com>,
        Michel Lespinasse <walken@...gle.com>,
        Catalin Marinas <catalin.marinas@....com>,
        Huang Ying <ying.huang@...el.com>,
        Jann Horn <jannh@...gle.com>, Feng Tang <feng.tang@...el.com>,
        Kevin Brodsky <Kevin.Brodsky@....com>,
        Michael Ellerman <mpe@...erman.id.au>,
        Shawn Anastasio <shawn@...stas.io>,
        Steven Price <steven.price@....com>,
        Nicholas Piggin <npiggin@...il.com>,
        Christian Brauner <christian.brauner@...ntu.com>,
        Jens Axboe <axboe@...nel.dk>,
        Gabriel Krisman Bertazi <krisman@...labora.com>,
        Peter Xu <peterx@...hat.com>,
        Suren Baghdasaryan <surenb@...gle.com>,
        Shakeel Butt <shakeelb@...gle.com>,
        Marco Elver <elver@...gle.com>,
        Daniel Jordan <daniel.m.jordan@...cle.com>,
        Nicolas Viennot <Nicolas.Viennot@...sigma.com>,
        Thomas Cedeno <thomascedeno@...gle.com>,
        Collin Fijalkovich <cfijalkovich@...gle.com>,
        Michal Hocko <mhocko@...e.com>,
        Miklos Szeredi <miklos@...redi.hu>,
        Chengguang Xu <cgxu519@...ernel.net>,
        Christian König 
        <ckoenig.leichtzumerken@...il.com>,
        "linux-unionfs@...r.kernel.org" <linux-unionfs@...r.kernel.org>,
        Linux API <linux-api@...r.kernel.org>,
        the arch/x86 maintainers <x86@...nel.org>,
        "<linux-fsdevel@...r.kernel.org>" <linux-fsdevel@...r.kernel.org>,
        Linux-MM <linux-mm@...ck.org>,
        Florian Weimer <fweimer@...hat.com>,
        Michael Kerrisk <mtk.manpages@...il.com>
Subject: Re: Removing Mandatory Locks

On Wed, 2021-08-18 at 11:34 +0200, Rodrigo Campos wrote:
> On Tue, Aug 17, 2021 at 6:49 PM Eric W. Biederman <ebiederm@...ssion.com> wrote:
> > 
> > Matthew Wilcox <willy@...radead.org> writes:
> > 
> > > On Fri, Aug 13, 2021 at 05:49:19PM -0700, Andy Lutomirski wrote:
> > > > [0] we have mandatory locks, too. Sigh.
> > > 
> > > I'd love to remove that.  Perhaps we could try persuading more of the
> > > distros to disable the CONFIG option first.
> > 
> > Yes.  The support is disabled in RHEL8.
> 
> If it helps, it seems to be enabled on the just released debian stable:
>     $ grep CONFIG_MANDATORY_FILE_LOCKING /boot/config-5.10.0-8-amd64
>     CONFIG_MANDATORY_FILE_LOCKING=y
> 
> Also the new 5.13 kernel in experimental has it too:
>     $ grep CONFIG_MANDATORY_FILE_LOCKING /boot/config-5.13.0-trunk-amd64
>     CONFIG_MANDATORY_FILE_LOCKING=y

A pity. It would have been nice if they had turned it off a while ago. I
guess I should have done more outreach at the time. Sigh...

In any case, I'm still inclined toward just ripping it out at this
point. It's hard to believe that anyone really uses it.
-- 
Jeff Layton <jlayton@...nel.org>