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Message-ID: <0d8f8e2b-166b-14bc-6879-a2521ea5b23d@infradead.org>
Date:   Tue, 27 Jun 2023 09:23:51 -0700
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Subject: Re: [PATCH 1/1] Add a new sysctl to disable io_uring system-wide
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To:     Matteo Rizzo <matteorizzo@google.com>, linux-doc@vger.kernel.org,
        linux-kernel@vger.kernel.org, io-uring@vger.kernel.org
Cc:     jordyzomer@google.com, evn@google.com, poprdi@google.com,
        corbet@lwn.net, axboe@kernel.dk, asml.silence@gmail.com,
        akpm@linux-foundation.org, keescook@chromium.org,
        rostedt@goodmis.org, dave.hansen@linux.intel.com,
        ribalda@chromium.org, chenhuacai@kernel.org, steve@sk2.org,
        gpiccoli@igalia.com, ldufour@linux.ibm.com
References: <20230627120058.2214509-1-matteorizzo@google.com>
 <20230627120058.2214509-2-matteorizzo@google.com>
From:   Randy Dunlap <rdunlap@infradead.org>
In-Reply-To: <20230627120058.2214509-2-matteorizzo@google.com>
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Hi--

On 6/27/23 05:00, Matteo Rizzo wrote:
> diff --git a/Documentation/admin-guide/sysctl/kernel.rst b/Documentation/admin-guide/sysctl/kernel.rst
> index d85d90f5d000..3c53a238332a 100644
> --- a/Documentation/admin-guide/sysctl/kernel.rst
> +++ b/Documentation/admin-guide/sysctl/kernel.rst
> @@ -450,6 +450,20 @@ this allows system administrators to override the
>  ``IA64_THREAD_UAC_NOPRINT`` ``prctl`` and avoid logs being flooded.
>  
>  
> +io_uring_disabled
> +=========================
> +
> +Prevents all processes from creating new io_uring instances. Enabling this
> +shrinks the kernel's attack surface.
> +
> += =============================================================
> +0 All processes can create io_uring instances as normal. This is the default
> +  setting.
> +1 io_uring is disabled. io_uring_setup always fails with -EPERM. Existing
> +  io_uring instances can still be used.
> += =============================================================

These table lines should be extended at least as far as the text that they
enclose. I.e., the top and bottom lines should be like:

> += ==========================================================================

thanks.
-- 
~Randy