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Date: Fri, 8 Dec 2023 17:40:41 -0800
From: Jakub Kicinski <kuba@kernel.org>
To: Pavel Begunkov <asml.silence@gmail.com>
Cc: io-uring@vger.kernel.org, Jens Axboe <axboe@kernel.dk>,
 jannh@google.com, davem@davemloft.net, edumazet@google.com,
 pabeni@redhat.com, netdev@vger.kernel.org
Subject: Re: [PATCH RESEND] io_uring/af_unix: disable sending io_uring over
 sockets
Message-ID: <20231208174041.3eddcc6b@kernel.org>
In-Reply-To: <c716c88321939156909cfa1bd8b0faaf1c804103.1701868795.git.asml.silence@gmail.com>
References: <c716c88321939156909cfa1bd8b0faaf1c804103.1701868795.git.asml.silence@gmail.com>
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On Wed,  6 Dec 2023 13:55:19 +0000 Pavel Begunkov wrote:
> File reference cycles have caused lots of problems for io_uring
> in the past, and it still doesn't work exactly right and races with
> unix_stream_read_generic(). The safest fix would be to completely
> disallow sending io_uring files via sockets via SCM_RIGHT, so there
> are no possible cycles invloving registered files and thus rendering
> SCM accounting on the io_uring side unnecessary.
> 
> Cc: stable@vger.kernel.org
> Fixes: 0091bfc81741b ("io_uring/af_unix: defer registered files gc to io_uring release")
> Reported-and-suggested-by: Jann Horn <jannh@google.com>
> Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>

Acked-by: Jakub Kicinski <kuba@kernel.org>
FWIW