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Subject: Re: [PATCH] io_uring: fix mm use with IORING_OP_{READ,WRITE}
To:     Pavel Begunkov <asml.silence@gmail.com>, io-uring@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <951bb84c8337aaac7654261a21b03506b2b8a001.1580914723.git.asml.silence@gmail.com>
From:   Jens Axboe <axboe@kernel.dk>
Message-ID: <df11c48e-f456-3b64-88d1-6012b1ac2bc8@kernel.dk>
Date:   Wed, 5 Feb 2020 08:54:20 -0700
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On 2/5/20 8:46 AM, Pavel Begunkov wrote:
> IORING_OP_{READ,WRITE} need mm to access user buffers, hence
> req->has_user check should go for them as well. Move the corresponding
> imports past the check.

I'd need to double check, but I think the has_user check should just go.
The import checks for access anyway, so we'll -EFAULT there if we
somehow messed up and didn't acquire the right mm.

-- 
Jens Axboe