linux-kernel - Re: [PATCH v2 1/2] fs/io_uring: fix O_PATH fds in openat, openat2, statx

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Date:   Fri, 8 May 2020 08:40:56 +0200
From:   Max Kellermann <mk@...all.com>
To:     axboe@...nel.dk
Cc:     linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v2 1/2] fs/io_uring: fix O_PATH fds in openat, openat2,
 statx

On 2020/05/08 08:38, Max Kellermann <mk@...all.com> wrote:
> This fails for `O_PATH` file descriptors, because io_file_get() calls
> fget(), which rejects `O_PATH` file descriptors.  To support `O_PATH`,
> fdget_raw() must be used (like path_init() in `fs/namei.c` does).
> This rejection causes io_req_set_file() to throw `-EBADF`.  This
> breaks the operations `openat`, `openat2` and `statx`, where `O_PATH`
> file descriptors are commonly used.

Code is the same as in v1, but I investigated the root cause of the
problem and updated the patch description.

Jens, I believe this should be a separate trivial commit just removing
those flags, to allow Greg to backport this to stable easily.

Max