All of lore.kernel.org
 help / color / mirror / Atom feed
From: Jarkko Sakkinen <jarkko@kernel.org>
To: Ulrich Windl <Ulrich.Windl@rz.uni-regensburg.de>
Cc: "systemd-devel@lists.freedesktop.org" 
	<systemd-devel@lists.freedesktop.org>,
	linux-hotplug@vger.kernel.org, linux-sgx@vger.kernel.org
Subject: Re: Antw: [EXT] Re: [systemd-devel] Creating executable device nodes in /dev?
Date: Fri, 11 Dec 2020 12:40:50 +0200	[thread overview]
Message-ID: <20201211104050.GC12091@kernel.org> (raw)
In-Reply-To: <5FD083BC020000A10003D6A0@gwsmtp.uni-regensburg.de>

On Wed, Dec 09, 2020 at 08:58:52AM +0100, Ulrich Windl wrote:
> >>> Jarkko Sakkinen <jarkko@kernel.org> schrieb am 09.12.2020 um 01:15 in Nachricht
> <20201209001521.GA64007@kernel.org>:
> 
> ...
> > 
> > What's the data that supports having noexec /dev anyway? With root
> > access I can then just use something else like /dev/shm mount.
> > 
> > Has there been out in the wild real world cases that noexec mount
> > of would have prevented?
> > 
> > For me this sounds a lot just something that "feels more secure"
> > without any measurable benefit. Can you prove me wrong?
> 
> I think the better question is: Why not allow it? I.e.: Why do you want to forbid it?
> 
> Event though I wouldn't like it myself, I could even think of noexec /tmp.

On an instance of an OS you should limit whatever is appropriate for
your use case. The debate is about sane defaults.

My argument is essentially that noexec /dev is not a sane default.
For anyone to who this makes sense, does such thing anyway. For
others, noexec /dev is only artificially useful.

> Regards,
> Ulrich

/Jarkko

WARNING: multiple messages have this Message-ID (diff)
From: Jarkko Sakkinen <jarkko@kernel.org>
To: Ulrich Windl <Ulrich.Windl@rz.uni-regensburg.de>
Cc: "systemd-devel@lists.freedesktop.org"
	<systemd-devel@lists.freedesktop.org>,
	linux-hotplug@vger.kernel.org, linux-sgx@vger.kernel.org
Subject: Re: Antw: [EXT] Re: [systemd-devel] Creating executable device nodes in /dev?
Date: Fri, 11 Dec 2020 10:40:50 +0000	[thread overview]
Message-ID: <20201211104050.GC12091@kernel.org> (raw)
In-Reply-To: <5FD083BC020000A10003D6A0@gwsmtp.uni-regensburg.de>

On Wed, Dec 09, 2020 at 08:58:52AM +0100, Ulrich Windl wrote:
> >>> Jarkko Sakkinen <jarkko@kernel.org> schrieb am 09.12.2020 um 01:15 in Nachricht
> <20201209001521.GA64007@kernel.org>:
> 
> ...
> > 
> > What's the data that supports having noexec /dev anyway? With root
> > access I can then just use something else like /dev/shm mount.
> > 
> > Has there been out in the wild real world cases that noexec mount
> > of would have prevented?
> > 
> > For me this sounds a lot just something that "feels more secure"
> > without any measurable benefit. Can you prove me wrong?
> 
> I think the better question is: Why not allow it? I.e.: Why do you want to forbid it?
> 
> Event though I wouldn't like it myself, I could even think of noexec /tmp.

On an instance of an OS you should limit whatever is appropriate for
your use case. The debate is about sane defaults.

My argument is essentially that noexec /dev is not a sane default.
For anyone to who this makes sense, does such thing anyway. For
others, noexec /dev is only artificially useful.

> Regards,
> Ulrich

/Jarkko

  reply	other threads:[~2020-12-11 10:42 UTC|newest]

Thread overview: 60+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-11-19 16:17 Creating executable device nodes in /dev? Andy Lutomirski
2020-11-19 16:17 ` Andy Lutomirski
2020-11-19 16:32 ` Zbigniew Jędrzejewski-Szmek
2020-11-19 18:05   ` Topi Miettinen
2020-11-19 18:05     ` Topi Miettinen
2020-12-08 18:07     ` Andy Lutomirski
2020-12-08 18:07       ` Andy Lutomirski
2020-12-08 20:45       ` Topi Miettinen
2020-12-08 20:45         ` Topi Miettinen
2020-12-08 21:30         ` Andy Lutomirski
2020-12-08 21:30           ` Andy Lutomirski
2020-12-08 23:15           ` Topi Miettinen
2020-12-08 23:15             ` Topi Miettinen
2020-12-09  0:15             ` Jarkko Sakkinen
2020-12-09  0:15               ` Jarkko Sakkinen
2020-12-09  0:42               ` Jarkko Sakkinen
2020-12-09  0:42                 ` Jarkko Sakkinen
2020-12-09  8:58                 ` Topi Miettinen
2020-12-09  8:58                   ` Topi Miettinen
2020-12-09  9:07                   ` Jethro Beekman
2020-12-09  9:07                     ` Jethro Beekman
2020-12-09 15:14                   ` Andy Lutomirski
2020-12-09 15:14                     ` Andy Lutomirski
2020-12-09 19:22                     ` Topi Miettinen
2020-12-09 19:22                       ` Topi Miettinen
2020-12-09 19:32                       ` Andy Lutomirski
2020-12-09 19:32                         ` Andy Lutomirski
2020-12-09 21:58                     ` Ben Hutchings
2020-12-09 21:58                       ` Ben Hutchings
2020-12-11 11:36                       ` Zbigniew Jędrzejewski-Szmek
2020-12-09  7:58               ` Antw: [EXT] Re: [systemd-devel] " Ulrich Windl
2020-12-09  7:58                 ` Ulrich Windl
2020-12-11 10:40                 ` Jarkko Sakkinen [this message]
2020-12-11 10:40                   ` Jarkko Sakkinen
2020-12-09  8:35               ` Topi Miettinen
2020-12-09  8:35                 ` Topi Miettinen
2020-12-11 10:46                 ` Jarkko Sakkinen
2020-12-11 10:46                   ` Jarkko Sakkinen
2020-12-11 11:29                   ` Greg KH
2020-12-11 11:29                     ` Greg KH
2020-12-12 11:51                     ` [systemd-devel] " Christian Brauner
2020-12-12 11:51                       ` Christian Brauner
2020-12-12 12:32                     ` Christian Brauner
2020-12-12 12:32                       ` Christian Brauner
2020-12-11 11:46                   ` Topi Miettinen
2020-12-11 11:46                     ` Topi Miettinen
2020-12-14  7:25                     ` Antw: [EXT] Re: [systemd-devel] " Ulrich Windl
2020-12-14  7:25                       ` Ulrich Windl
2020-12-15  4:19                       ` Jarkko Sakkinen
2020-12-15  4:19                         ` Jarkko Sakkinen
2020-12-15  4:27                         ` Jarkko Sakkinen
2020-12-15  4:27                           ` Jarkko Sakkinen
2020-12-16 10:03                         ` Ulrich Windl
2020-12-16 10:03                           ` Ulrich Windl
2020-12-16 13:05                           ` Topi Miettinen
2020-12-16 13:05                             ` Topi Miettinen
2020-12-22 22:14                             ` Jarkko Sakkinen
2020-12-22 22:14                               ` Jarkko Sakkinen
2020-12-09  0:03       ` Jarkko Sakkinen
2020-12-09  0:03         ` Jarkko Sakkinen

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20201211104050.GC12091@kernel.org \
    --to=jarkko@kernel.org \
    --cc=Ulrich.Windl@rz.uni-regensburg.de \
    --cc=linux-hotplug@vger.kernel.org \
    --cc=linux-sgx@vger.kernel.org \
    --cc=systemd-devel@lists.freedesktop.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.