public inbox for [email protected]
 help / color / mirror / Atom feed
From: Paul Moore <[email protected]>
To: Joel Granados <[email protected]>
Cc: Kanchan Joshi <[email protected]>,
	[email protected], [email protected],
	[email protected], [email protected]
Subject: Re: [RFC 1/1] Use ioctl selinux callback io_uring commands that implement the ioctl op convention
Date: Thu, 17 Nov 2022 17:10:07 -0500	[thread overview]
Message-ID: <CAHC9VhSa3Yrjf9z5L0oS8Cx=20gUrgfA8evizoVjBNs4AB_cXg@mail.gmail.com> (raw)
In-Reply-To: <20221117094004.b5l64ipicitphkun@localhost>

On Thu, Nov 17, 2022 at 4:40 AM Joel Granados <[email protected]> wrote:
> On Wed, Nov 16, 2022 at 02:21:14PM -0500, Paul Moore wrote:

...

> > * As we discussed previously, the real problem is the fact that we are
> > missing the necessary context in the LSM hook to separate the
> > different types of command targets.  With traditional ioctls we can
> > look at the ioctl number and determine both the type of
> > device/subsystem/etc. as well as the operation being requested; there
> > is no such information available with the io_uring command
> > passthrough.  In this sense, the io_uring command passthrough is
> > actually worse than traditional ioctls from an access control
> > perspective.  Until we have an easy(ish)[1] way to determine the
> > io_uring command target type, changes like the one suggested here are
> > going to be doomed as each target type is free to define their own
> > io_uring commands.
>
> The only thing that comes immediately to mind is that we can have
> io_uring users define a function that is then passed to the LSM
> infrastructure. This function will have all the logic to give relative
> context to LSM. It would be general enough to fit all the possible commands
> and the logic would be implemented in the "drivers" side so there is no
> need for LSM folks to know all io_uring users.

Passing a function pointer to the LSM to fetch, what will likely be
just a constant value, seems kinda ugly, but I guess we only have ugly
options at this point.  I imagine we could cache the result in the
inode's security blob, assuming the device type remained constant (I
can't think of why it would change); still ugly but at least it
doesn't require multiple indirect calls.

It's probably worth throwing together a quick patch so we can discuss
this further.

--
paul-moore.com

  reply	other threads:[~2022-11-17 22:10 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <CGME20221116125430eucas1p2f2969a4a795614ce3b8c06f9ea3be36f@eucas1p2.samsung.com>
2022-11-16 12:50 ` [RFC 0/1] RFC on how to include LSM hooks for io_uring commands Joel Granados
     [not found]   ` <CGME20221116125431eucas1p1dfd03b80863fce674a7c662660c94092@eucas1p1.samsung.com>
2022-11-16 12:50     ` [RFC 1/1] Use ioctl selinux callback io_uring commands that implement the ioctl op convention Joel Granados
2022-11-16 17:38       ` Kanchan Joshi
2022-11-16 19:21         ` Paul Moore
2022-11-17  9:40           ` Joel Granados
2022-11-17 22:10             ` Paul Moore [this message]
2022-11-21 19:53               ` Luis Chamberlain
2022-11-21 21:05                 ` Paul Moore
2022-11-22 11:18                   ` Joel Granados
2022-11-22 14:04                   ` Ming Lei
2022-11-28 10:13                     ` Joel Granados
2022-11-28 10:59                       ` Ming Lei
2022-11-22 11:15                 ` Joel Granados
2022-11-17  9:25         ` Joel Granados

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='CAHC9VhSa3Yrjf9z5L0oS8Cx=20gUrgfA8evizoVjBNs4AB_cXg@mail.gmail.com' \
    [email protected] \
    [email protected] \
    [email protected] \
    [email protected] \
    [email protected] \
    [email protected] \
    [email protected] \
    /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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox