Re: [PATCH 2/4] io_uring: move CLOSE req->file checking into handler

[Pavel Begunkov <asml.silence@gmail.com>]

On 04/03/2020 02:50, Jens Axboe wrote:
> In preparation for not needing req->file in on the prep side at all.
> 
> Signed-off-by: Jens Axboe <axboe@kernel.dk>
> ---
>  fs/io_uring.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/fs/io_uring.c b/fs/io_uring.c
> index 0464efbeba25..9d5e49a39dba 100644
> --- a/fs/io_uring.c
> +++ b/fs/io_uring.c
> @@ -3367,10 +3367,6 @@ static int io_close_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
>  		return -EBADF;
>  
>  	req->close.fd = READ_ONCE(sqe->fd);
> -	if (req->file->f_op == &io_uring_fops ||
> -	    req->close.fd == req->ctx->ring_fd)
> -		return -EBADF;
> -
>  	return 0;
>  }
>  
> @@ -3400,6 +3396,10 @@ static int io_close(struct io_kiocb *req, bool force_nonblock)
>  {
>  	int ret;
>  
> +	if (req->file->f_op == &io_uring_fops ||
> +	    req->close.fd == req->ctx->ring_fd)
> +		return -EBADF;
> +

@ring_fd's and @ring_file's lifetimes are bound by call to io_submit_sqes(), and
they're undefined outside. For the same reason both of them should be used with
ctx->uring_lock hold.


>  	req->close.put_file = NULL;
>  	ret = __close_fd_get_file(req->close.fd, &req->close.put_file);
>  	if (ret < 0)
> 

-- 
Pavel Begunkov