linux-kernel - Re: [PATCH v2 0/5] pid: add pidfd

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]

Date:   Sat, 30 Mar 2019 17:37:51 +0100
From:   Christian Brauner <christian@...uner.io>
To:     Linus Torvalds <torvalds@...ux-foundation.org>
Cc:     Jann Horn <jannh@...gle.com>, Andrew Lutomirski <luto@...nel.org>,
        David Howells <dhowells@...hat.com>,
        "Serge E. Hallyn" <serge@...lyn.com>,
        Linux API <linux-api@...r.kernel.org>,
        Linux List Kernel Mailing <linux-kernel@...r.kernel.org>,
        Arnd Bergmann <arnd@...db.de>,
        "Eric W. Biederman" <ebiederm@...ssion.com>,
        Konstantin Khlebnikov <khlebnikov@...dex-team.ru>,
        Kees Cook <keescook@...omium.org>,
        Alexey Dobriyan <adobriyan@...il.com>,
        Thomas Gleixner <tglx@...utronix.de>,
        Michael Kerrisk-manpages <mtk.manpages@...il.com>,
        Jonathan Kowalski <bl0pbl33p@...il.com>,
        "Dmitry V. Levin" <ldv@...linux.org>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Oleg Nesterov <oleg@...hat.com>,
        Nagarathnam Muthusamy <nagarathnam.muthusamy@...cle.com>,
        Aleksa Sarai <cyphar@...har.com>,
        Al Viro <viro@...iv.linux.org.uk>,
        Joel Fernandes <joel@...lfernandes.org>,
        Daniel Colascione <dancol@...gle.com>
Subject: Re: [PATCH v2 0/5] pid: add pidfd_open()

On Sat, Mar 30, 2019 at 09:24:23AM -0700, Linus Torvalds wrote:
> On Sat, Mar 30, 2019 at 9:19 AM Christian Brauner <christian@...uner.io> wrote:
> >
> > From pure API perspective that's all I care about: independence of procfs.
> > Once we have pidfd_open() we can cleanly signal threads etc.
> 
> But "independence from procfs" means that you damn well don't then do
> "oh, now I have a pidfd, I want to turn it into a /proc fd and then
> munge around there".
> 
> So I'm literally saying that it had better really *be* independent
> from /proc. It is the standalone version, but it's most definitely
> also the version that doesn't then give you secret access to /proc.
> 
> And it weorries me a lot that people are trying to play these kinds of
> games. I'm just seeing some android patch that adds this horror and
> then starts using it.

The original need for this conversion thing came from Android indeed. I
won't go forward with any such patches. 

Christian