Follow @Openwall on Twitter for new release announcements and other news
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Thu, 27 Aug 2020 07:50:44 -0600
From: Jens Axboe <>
To: Stefano Garzarella <>
Cc: Aleksa Sarai <>,
 Kernel Hardening <>,
 Jann Horn <>,,
 Christian Brauner <>,, Alexander Viro <>,
 Stefan Hajnoczi <>,,
 Sargun Dhillon <>, Kees Cook <>,
 Jeff Moyer <>
Subject: Re: [PATCH v5 0/3] io_uring: add restrictions to support untrusted
 applications and guests

On 8/27/20 7:40 AM, Stefano Garzarella wrote:
> v5:
>  - explicitly assigned enum values [Kees]
>  - replaced kmalloc/copy_from_user with memdup_user [kernel test robot]
>  - added Kees' R-b tags
> v4:
> v3:
> RFC v2:
> RFC v1:
> Following the proposal that I send about restrictions [1], I wrote this series
> to add restrictions in io_uring.
> I also wrote helpers in liburing and a test case (test/register-restrictions.c)
> available in this repository:
> (branch: io_uring_restrictions)
> Just to recap the proposal, the idea is to add some restrictions to the
> operations (sqe opcode and flags, register opcode) to safely allow untrusted
> applications or guests to use io_uring queues.
> The first patch changes io_uring_register(2) opcodes into an enumeration to
> keep track of the last opcode available.
> The second patch adds IOURING_REGISTER_RESTRICTIONS opcode and the code to
> handle restrictions.
> The third patch adds IORING_SETUP_R_DISABLED flag to start the rings disabled,
> allowing the user to register restrictions, buffers, files, before to start
> processing SQEs.
> Comments and suggestions are very welcome.

Looks good to me, just a few very minor comments in patch 2. If you
could fix those up, let's get this queued for 5.10.

Jens Axboe

Powered by blists - more mailing lists

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.