From: Ingo Molnar <mingo@kernel.org>
To: Djalal Harouni <tixxdz@opendz.org>
Cc: Andy Lutomirski <luto@amacapital.net>,
"Eric W. Biederman" <ebiederm@xmission.com>,
Kees Cook <keescook@chromium.org>,
Al Viro <viro@zeniv.linux.org.uk>,
Andrew Morton <akpm@linux-foundation.org>,
Linus Torvalds <torvalds@linux-foundation.org>,
"Serge E. Hallyn" <serge.hallyn@ubuntu.com>,
Cyrill Gorcunov <gorcunov@openvz.org>,
David Rientjes <rientjes@google.com>,
LKML <linux-kernel@vger.kernel.org>,
Linux FS Devel <linux-fsdevel@vger.kernel.org>,
kernel-hardening@lists.openwall.com,
Djalal Harouni <tixxdz@gmail.com>
Subject: Re: [PATCH v2 0/9] procfs: protect /proc/<pid>/* files with file->f_cred
Date: Thu, 3 Oct 2013 15:39:39 +0200 [thread overview]
Message-ID: <20131003133939.GB28308@gmail.com> (raw)
In-Reply-To: <20131003125609.GB3619@dztty>
* Djalal Harouni <tixxdz@opendz.org> wrote:
> On Thu, Oct 03, 2013 at 08:22:56AM +0200, Ingo Molnar wrote:
> >
> > * Djalal Harouni <tixxdz@opendz.org> wrote:
> >
> > > * You can't do it for /proc/*/stat otherwise you will break userspace
> > > "ps"..., ps must access /proc/1/stat etc... so the proposed solution
> > > will work without any side effect.
> >
> > The thing is, returning -EINVAL is not the only way to reject access to
> > privileged information!
>
> > In the /proc/1/stat case a compatibility quirk can solve the problem:
> > create a special 'dummy' process inode for invalid accesses and give
> > it to ps, with all fields present but zero.
>
> Hmm, we already return zero for the fields that must be protected.
> Already done.
>
> Not all fields need to be zero ? If so, yes it could be done as you
> propose and avoid the 'if permitted' test each time... but we don't want
> to do it
Indeed some fields need to be available, for utilities like 'top' to work.
Thanks,
Ingo
prev parent reply other threads:[~2013-10-03 13:39 UTC|newest]
Thread overview: 68+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-10-01 20:26 [PATCH v2 0/9] procfs: protect /proc/<pid>/* files with file->f_cred Djalal Harouni
2013-10-01 20:26 ` [PATCH v2 1/9] procfs: add proc_same_open_cred() to check if the cred have changed Djalal Harouni
2013-10-01 20:26 ` [PATCH v2 2/9] procfs: add proc_allow_access() to check if file's opener may access task Djalal Harouni
2013-10-02 1:36 ` Andy Lutomirski
2013-10-02 14:55 ` Djalal Harouni
2013-10-02 16:44 ` Andy Lutomirski
2013-10-03 14:36 ` Djalal Harouni
2013-10-03 15:12 ` Andy Lutomirski
2013-10-03 19:29 ` Djalal Harouni
2013-10-03 19:37 ` Andy Lutomirski
2013-10-03 20:13 ` Djalal Harouni
2013-10-03 21:09 ` Andy Lutomirski
2013-10-04 8:59 ` Djalal Harouni
2013-10-04 15:40 ` Andy Lutomirski
2013-10-04 18:23 ` Djalal Harouni
2013-10-04 18:34 ` Andy Lutomirski
2013-10-04 19:11 ` Djalal Harouni
2013-10-04 19:16 ` Andy Lutomirski
2013-10-04 19:27 ` Djalal Harouni
2013-10-04 19:32 ` Andy Lutomirski
2013-10-04 19:41 ` Djalal Harouni
2013-10-04 22:17 ` Andy Lutomirski
2013-10-04 22:55 ` Eric W. Biederman
2013-10-04 22:59 ` Andy Lutomirski
2013-10-04 23:08 ` Andy Lutomirski
2013-10-05 0:35 ` Eric W. Biederman
2013-10-09 10:35 ` Djalal Harouni
2013-10-05 13:23 ` Djalal Harouni
2013-10-07 21:41 ` Andy Lutomirski
2013-10-09 10:54 ` Djalal Harouni
2013-10-09 11:15 ` Djalal Harouni
2013-10-09 17:27 ` Andy Lutomirski
2013-10-13 10:18 ` Djalal Harouni
2013-10-01 20:26 ` [PATCH v2 3/9] procfs: Document the proposed solution to protect procfs entries Djalal Harouni
2013-10-01 20:26 ` [PATCH v2 4/9] procfs: make /proc/*/{stack,syscall} 0400 Djalal Harouni
2013-10-01 20:26 ` [PATCH v2 5/9] procfs: make /proc entries that use seq files able to access file->f_cred Djalal Harouni
2013-10-01 20:26 ` [PATCH v2 6/9] procfs: add permission checks on the file's opener of /proc/*/stat Djalal Harouni
2013-10-02 1:39 ` Andy Lutomirski
2013-10-02 15:14 ` Djalal Harouni
2013-10-02 16:46 ` Andy Lutomirski
2013-10-02 19:00 ` Djalal Harouni
2013-10-01 20:26 ` [PATCH v2 7/9] procfs: add permission checks on the file's opener of /proc/*/personality Djalal Harouni
2013-10-01 20:26 ` [PATCH v2 8/9] procfs: improve permission checks on /proc/*/stack Djalal Harouni
2013-10-01 20:26 ` [PATCH v2 9/9] procfs: improve permission checks on /proc/*/syscall Djalal Harouni
2013-10-02 1:40 ` [PATCH v2 0/9] procfs: protect /proc/<pid>/* files with file->f_cred Andy Lutomirski
2013-10-02 14:37 ` Djalal Harouni
2013-10-02 16:51 ` Andy Lutomirski
2013-10-02 17:48 ` Kees Cook
2013-10-02 18:00 ` Andy Lutomirski
2013-10-02 18:07 ` Kees Cook
2013-10-03 23:14 ` Julien Tinnes
2013-10-02 18:26 ` Djalal Harouni
2013-10-02 18:41 ` Djalal Harouni
2013-10-02 18:22 ` Djalal Harouni
2013-10-02 18:35 ` Kees Cook
2013-10-02 18:48 ` Djalal Harouni
2013-10-02 19:43 ` Kees Cook
2013-10-03 6:12 ` Ingo Molnar
2013-10-03 12:29 ` Djalal Harouni
2013-10-03 15:15 ` Andy Lutomirski
2013-10-03 15:40 ` Djalal Harouni
2013-10-03 15:50 ` Andy Lutomirski
2013-10-03 18:37 ` Djalal Harouni
2013-10-04 9:05 ` Djalal Harouni
2013-10-02 18:12 ` Djalal Harouni
2013-10-03 6:22 ` Ingo Molnar
2013-10-03 12:56 ` Djalal Harouni
2013-10-03 13:39 ` Ingo Molnar [this message]
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