io_uring: missed req_init_async() for IOSQE_ASYNC

to #29608102

commit 3e863ea3bb1a2203ae648eb272db0ce6a1a2072c upstream.

IOSQE_ASYNC branch of io_queue_sqe() is another place where an
unitialised req->work can be accessed (i.e. prior io_req_init_async()).
Nothing really bad though, it just looses IO_WQ_WORK_CONCURRENT flag.
Signed-off-by: NPavel Begunkov <asml.silence@gmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>
Signed-off-by: NJiufei Xue <jiufei.xue@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

fs/io_uring.c

@@ -5692,6 +5692,7 @@ static void io_queue_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 		 * Never try inline submit of IOSQE_ASYNC is set, go straight
 		 * to async execution.
 		 */
+		io_req_init_async(req);
 		req->work.flags |= IO_WQ_WORK_CONCURRENT;
 		io_queue_async_work(req);
 	} else {