From: Oleg Nesterov <oleg@redhat.com>
To: richard -rw- weinberger <richard.weinberger@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
Djalal Harouni <tixxdz@opendz.org>,
Alan Cox <alan@lxorguk.ukuu.org.uk>,
linux-kernel@vger.kernel.org,
kernel-hardening@lists.openwall.com,
Andrew Morton <akpm@linux-foundation.org>,
Al Viro <viro@zeniv.linux.org.uk>,
Alexey Dobriyan <adobriyan@gmail.com>,
"Eric W. Biederman" <ebiederm@xmission.com>,
Vasiliy Kulikov <segoon@openwall.com>,
Kees Cook <keescook@chromium.org>,
Solar Designer <solar@openwall.com>,
WANG Cong <xiyou.wangcong@gmail.com>,
James Morris <james.l.morris@oracle.com>,
linux-security-module@vger.kernel.org,
linux-fsdevel@vger.kernel.org,
Greg KH <gregkh@linuxfoundation.org>, Ingo Molnar <mingo@elte.hu>,
Stephen Wilson <wilsons@start.ca>,
"Jason A. Donenfeld" <Jason@zx2c4.com>
Subject: Re: self_exec_id/parent_exec_id && CLONE_PARENT
Date: Sun, 11 Mar 2012 19:39:00 +0100 [thread overview]
Message-ID: <20120311183900.GA7031@redhat.com> (raw)
In-Reply-To: <CAFLxGvx2zc-qOYCzHEEzU6XY1JHqCqzU2+Kiq=e0YKfqqJWLnQ@mail.gmail.com>
On 03/11, richard -rw- weinberger wrote:
>
> On Sun, Mar 11, 2012 at 7:02 PM, Linus Torvalds
> <torvalds@linux-foundation.org> wrote:
> > On Sun, Mar 11, 2012 at 10:49 AM, Oleg Nesterov <oleg@redhat.com> wrote:
> >>
> >> I am also asking because the change above looks like the fix to me.
> >> The child must not control its ->exit_signal, it is the parent who
> >> decides which signal the child should use for notification.
> >>
> >> And to me, clone(CLONE_PARENT | SIGXXX) looks like a violation of
> >> rule above.
> >
> > SIGXXX is for doing things like AIO with threads, but it would never
> > be used together with CLONE_PARENT, that would be odd and wrong.
> >
> > So I think we could disallow that - or at least try. See if anybody
> > notices, and if it breaks anything.
> >
>
> UserModeLinux is using CLONE_PARENT | CLONE_FILES | SIGCHLD.
> Is this a problem?
This depends on how the forking process was created, and what its
parent expects.
If it was forked with SIGCHLD as well, then no problems. Otherwise
the parent can notice the difference.
Oleg.
next prev parent reply other threads:[~2012-03-11 18:39 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-03-10 23:25 [PATCH 0/9] proc: protect /proc/<pid>/* files across execve Djalal Harouni
2012-03-10 23:25 ` [PATCH 1/9] exec: add a global execve counter Djalal Harouni
2012-03-11 0:12 ` Linus Torvalds
2012-03-11 0:36 ` Linus Torvalds
2012-03-11 0:58 ` Linus Torvalds
2012-03-11 8:24 ` Solar Designer
2012-03-11 9:56 ` Ingo Molnar
2012-03-11 14:03 ` Alan Cox
2012-03-11 17:15 ` Djalal Harouni
2012-03-11 8:39 ` Djalal Harouni
2012-03-11 9:40 ` Solar Designer
2012-03-11 17:25 ` Oleg Nesterov
2012-03-11 17:49 ` self_exec_id/parent_exec_id && CLONE_PARENT Oleg Nesterov
2012-03-11 18:02 ` Linus Torvalds
2012-03-11 18:37 ` richard -rw- weinberger
2012-03-11 18:39 ` Oleg Nesterov [this message]
2012-03-14 18:55 ` [PATCH 0/1] (Was: self_exec_id/parent_exec_id && CLONE_PARENT) Oleg Nesterov
2012-03-14 18:55 ` [PATCH 1/1] CLONE_PARENT shouldn't allow to set ->exit_signal Oleg Nesterov
2012-03-18 18:25 ` Linus Torvalds
2012-03-18 20:53 ` Oleg Nesterov
2012-03-11 22:48 ` [PATCH 1/9] exec: add a global execve counter Linus Torvalds
2012-03-11 23:32 ` Djalal Harouni
2012-03-11 23:42 ` Linus Torvalds
2012-03-12 0:25 ` Djalal Harouni
2012-03-12 10:11 ` Linus Torvalds
2012-03-12 14:01 ` Djalal Harouni
2012-03-11 23:36 ` Djalal Harouni
2012-03-12 14:34 ` Oleg Nesterov
2012-03-10 23:25 ` [PATCH 2/9] proc: add proc_file_private struct to store private information Djalal Harouni
2012-03-10 23:25 ` [PATCH 3/9] proc: new proc_exec_id_ok() helper function Djalal Harouni
2012-03-10 23:25 ` [PATCH 4/9] proc: protect /proc/<pid>/* INF files from reader across execve Djalal Harouni
2012-03-10 23:25 ` [PATCH 5/9] proc: add protection support for /proc/<pid>/* ONE files Djalal Harouni
2012-03-10 23:25 ` [PATCH 6/9] proc: protect /proc/<pid>/* ONE files from reader across execve Djalal Harouni
2012-03-10 23:25 ` [PATCH 7/9] proc: protect /proc/<pid>/{maps,smaps,numa_maps} Djalal Harouni
2012-03-10 23:25 ` [PATCH 8/9] proc: protect /proc/<pid>/{environ,pagemap} across execve Djalal Harouni
2012-03-11 8:05 ` Alexey Dobriyan
2012-03-11 17:01 ` Djalal Harouni
2012-03-10 23:25 ` [PATCH 9/9] proc: improve and clean up /proc/<pid>/mem protection Djalal Harouni
2012-03-11 0:01 ` [PATCH 0/9] proc: protect /proc/<pid>/* files across execve Linus Torvalds
2012-03-11 0:27 ` Djalal Harouni
2012-03-11 8:46 ` Djalal Harouni
2012-03-11 10:35 ` exec_id protection from bad child exit signals (was: Re: [PATCH 0/9] proc: protect /proc/<pid>/* files across execve) Solar Designer
2012-03-11 18:20 ` Oleg Nesterov
2012-03-12 19:13 ` [PATCH 0/9] proc: protect /proc/<pid>/* files across execve Eric W. Biederman
2012-03-12 20:44 ` Djalal Harouni
2012-03-12 21:47 ` Eric W. Biederman
2012-03-12 22:41 ` Djalal Harouni
2012-03-12 23:10 ` Eric W. Biederman
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