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Subject: Re: [PATCH] fs/io_uring: fix O_PATH fds in openat, openat2, statx
To:     Al Viro <viro@zeniv.linux.org.uk>, Max Kellermann <mk@cm4all.com>
Cc:     linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        stable@vger.kernel.org
References: <20200507185725.15840-1-mk@cm4all.com>
 <20200507190131.GF23230@ZenIV.linux.org.uk>
From:   Jens Axboe <axboe@kernel.dk>
Message-ID: <4cac0e53-656c-50f0-3766-ae3cc6c0310a@kernel.dk>
Date:   Thu, 7 May 2020 13:05:23 -0600
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On 5/7/20 1:01 PM, Al Viro wrote:
> On Thu, May 07, 2020 at 08:57:25PM +0200, Max Kellermann wrote:
>> If an operation's flag `needs_file` is set, the function
>> io_req_set_file() calls io_file_get() to obtain a `struct file*`.
>>
>> This fails for `O_PATH` file descriptors, because those have no
>> `struct file*`
> 
> O_PATH descriptors most certainly *do* have that.  What the hell
> are you talking about?

Yeah, hence I was interested in the test case. Since this is
bypassing that part, was assuming we'd have some logic error
that attempted a file grab for a case where we shouldn't.

-- 
Jens Axboe