You don’t need a visa. The rule is: “Visas are not required of citizens of the following countries, who transit through Pudong Airport or Hongqiao Airport of Shanghai, provided they hold valid passports, visas for the onward countries, final destination tickets and have booked seats, and stay in Shanghai for less than 48 hours: Republic of Korea, United States, Canada, Australia, New Zealand, Germany, France, Netherlands, Belgium, Luxemburg, Portugal, Spain, Italy, Austria, Greece.”