From: Kees Cook <keescook@chromium.org>
To: "Theodore Y. Ts'o" <tytso@mit.edu>
Cc: Topi Miettinen <toiwoton@gmail.com>,
Luis Chamberlain <mcgrof@kernel.org>,
Alexey Dobriyan <adobriyan@gmail.com>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"open list:FILESYSTEMS (VFS and infrastructure)"
<linux-fsdevel@vger.kernel.org>
Subject: Re: [PATCH] Allow restricting permissions in /proc/sys
Date: Tue, 12 Nov 2019 15:15:15 -0800 [thread overview]
Message-ID: <201911121514.DA3BEED0@keescook> (raw)
In-Reply-To: <20191103175648.GA4603@mit.edu>
On Sun, Nov 03, 2019 at 12:56:48PM -0500, Theodore Y. Ts'o wrote:
> On Sun, Nov 03, 2019 at 04:55:48PM +0200, Topi Miettinen wrote:
> > Several items in /proc/sys need not be accessible to unprivileged
> > tasks. Let the system administrator change the permissions, but only
> > to more restrictive modes than what the sysctl tables allow.
> >
> > Signed-off-by: Topi Miettinen <toiwoton@gmail.com>
>
> Why should restruct the system administrator from changing the
> permissions to one which is more lax than what the sysctl tables?
>
> The system administrator is already very much trusted. Why should we
> take that discretion away from the system administrator?
Generally speaking, they're there to provide some sense of boundary
between uid 0 and the kernel proper. I think it's correct to not allow
weakening of these permissions (which is the current state: no change at
all).
--
Kees Cook
next prev parent reply other threads:[~2019-11-12 23:15 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-11-03 14:55 [PATCH] Allow restricting permissions in /proc/sys Topi Miettinen
2019-11-03 17:56 ` Theodore Y. Ts'o
2019-11-03 19:24 ` Topi Miettinen
2019-11-12 23:15 ` Kees Cook [this message]
2019-11-03 18:50 ` Eric W. Biederman
2019-11-03 19:38 ` Topi Miettinen
2019-11-04 15:44 ` Eric W. Biederman
2019-11-04 17:58 ` Topi Miettinen
2019-11-04 23:41 ` Eric W. Biederman
2019-11-05 7:35 ` Topi Miettinen
2019-11-12 23:19 ` Kees Cook
2019-11-13 1:04 ` Luis Chamberlain
2019-11-12 23:22 ` Christian Brauner
2019-11-13 4:50 ` Andy Lutomirski
2019-11-13 10:52 ` Topi Miettinen
2019-11-13 16:00 ` Jann Horn
2019-11-13 16:19 ` Topi Miettinen
2019-11-13 16:40 ` Jann Horn
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