io_uring: check file O_NONBLOCK state for accept

task #27774850

commit e697deed834de15d2322d0619d51893022c90ea2 upstream.

If the socket is O_NONBLOCK, we should complete the accept request
with -EAGAIN when data is not ready.
Signed-off-by: NJiufei Xue <jiufei.xue@linux.alibaba.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

fs/io_uring.c

@@ -3969,6 +3969,9 @@ static int io_accept(struct io_kiocb *req, bool force_nonblock)
 {
 	int ret;
 
+	if (req->file->f_flags & O_NONBLOCK)
+		req->flags |= REQ_F_NOWAIT;
+
 	ret = __io_accept(req, force_nonblock);
 	if (ret == -EAGAIN && force_nonblock) {
 		req->work.func = io_accept_finish;