Return ticket through shangai

I have a return ticket between osaka and shanghai and then within that time frame want to get a return ticket from shanghai to Laos, can i get the visa free transit for both ends of this trip. I plan to transit in shanghai for 3 days and the. Carry on to Laos and then on my way back to japan stay one night again in shanghai. So it would be osaka>shanghai>vientiane>shanghai>osaka any advice would be so helpful!