From: Stefano Garzarella <[email protected]>
To: Jens Axboe <[email protected]>
Cc: Alexander Viro <[email protected]>,
Kernel Hardening <[email protected]>,
Kees Cook <[email protected]>, Aleksa Sarai <[email protected]>,
Stefan Hajnoczi <[email protected]>,
Christian Brauner <[email protected]>,
Sargun Dhillon <[email protected]>, Jann Horn <[email protected]>,
[email protected], [email protected],
Jeff Moyer <[email protected]>,
[email protected]
Subject: Re: [PATCH RFC v2 2/3] io_uring: add IOURING_REGISTER_RESTRICTIONS opcode
Date: Tue, 21 Jul 2020 12:40:09 +0200 [thread overview]
Message-ID: <20200721104009.lg626hmls5y6ihdr@steredhat> (raw)
In-Reply-To: <[email protected]>
On Thu, Jul 16, 2020 at 03:26:51PM -0600, Jens Axboe wrote:
> On 7/16/20 6:48 AM, Stefano Garzarella wrote:
> > diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h
> > index efc50bd0af34..0774d5382c65 100644
> > --- a/include/uapi/linux/io_uring.h
> > +++ b/include/uapi/linux/io_uring.h
> > @@ -265,6 +265,7 @@ enum {
> > IORING_REGISTER_PROBE,
> > IORING_REGISTER_PERSONALITY,
> > IORING_UNREGISTER_PERSONALITY,
> > + IORING_REGISTER_RESTRICTIONS,
> >
> > /* this goes last */
> > IORING_REGISTER_LAST
> > @@ -293,4 +294,30 @@ struct io_uring_probe {
> > struct io_uring_probe_op ops[0];
> > };
> >
> > +struct io_uring_restriction {
> > + __u16 opcode;
> > + union {
> > + __u8 register_op; /* IORING_RESTRICTION_REGISTER_OP */
> > + __u8 sqe_op; /* IORING_RESTRICTION_SQE_OP */
> > + };
> > + __u8 resv;
> > + __u32 resv2[3];
> > +};
> > +
> > +/*
> > + * io_uring_restriction->opcode values
> > + */
> > +enum {
> > + /* Allow an io_uring_register(2) opcode */
> > + IORING_RESTRICTION_REGISTER_OP,
> > +
> > + /* Allow an sqe opcode */
> > + IORING_RESTRICTION_SQE_OP,
> > +
> > + /* Only allow fixed files */
> > + IORING_RESTRICTION_FIXED_FILES_ONLY,
> > +
> > + IORING_RESTRICTION_LAST
> > +};
> > +
>
> Not sure I totally love this API. Maybe it'd be cleaner to have separate
> ops for this, instead of muxing it like this. One for registering op
> code restrictions, and one for disallowing other parts (like fixed
> files, etc).
>
> I think that would look a lot cleaner than the above.
>
Talking with Stefan, an alternative, maybe more near to your suggestion,
would be to remove the 'struct io_uring_restriction' and add the
following register ops:
/* Allow an sqe opcode */
IORING_REGISTER_RESTRICTION_SQE_OP
/* Allow an io_uring_register(2) opcode */
IORING_REGISTER_RESTRICTION_REG_OP
/* Register IORING_RESTRICTION_* */
IORING_REGISTER_RESTRICTION_OP
enum {
/* Only allow fixed files */
IORING_RESTRICTION_FIXED_FILES_ONLY,
IORING_RESTRICTION_LAST
}
We can also enable restriction only when the rings started, to avoid to
register IORING_REGISTER_ENABLE_RINGS opcode. Once rings are started,
the restrictions cannot be changed or disabled.
If you agree, I'll send a v3 following this.
Thanks,
Stefano
next prev parent reply other threads:[~2020-07-21 10:40 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-16 12:48 [PATCH RFC v2 0/3] io_uring: add restrictions to support untrusted applications and guests Stefano Garzarella
2020-07-16 12:48 ` [PATCH RFC v2 1/3] io_uring: use an enumeration for io_uring_register(2) opcodes Stefano Garzarella
2020-07-16 20:16 ` Pavel Begunkov
2020-07-16 20:42 ` Jens Axboe
2020-07-16 20:47 ` Pavel Begunkov
2020-07-16 20:51 ` Jens Axboe
2020-07-16 21:20 ` Jens Axboe
2020-07-17 8:13 ` Stefano Garzarella
2020-07-16 12:48 ` [PATCH RFC v2 2/3] io_uring: add IOURING_REGISTER_RESTRICTIONS opcode Stefano Garzarella
2020-07-16 21:26 ` Jens Axboe
2020-07-17 8:55 ` Stefano Garzarella
2020-07-21 10:40 ` Stefano Garzarella [this message]
2020-07-21 17:11 ` Jens Axboe
2020-07-22 2:35 ` Daurnimator
2020-07-22 14:14 ` Stefano Garzarella
2020-07-22 14:29 ` Stefano Garzarella
2020-07-16 12:48 ` [PATCH RFC v2 3/3] io_uring: allow disabling rings during the creation Stefano Garzarella
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=20200721104009.lg626hmls5y6ihdr@steredhat \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[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