This is a very timely question.
I used this to check if Canvas would be accessible in China https://en.greatfire.org It seemed to work fine and showed that our instance of canvas would probably be fine.
However, as @tdw suggests in this blog https://community.canvaslms.com/thread/14878-support-for-online-students-in-china this depends on so many things.
Many variables are at play including the student's region, the student's ISP, the time of year (e.g. is it close to June 4th?), other filtered activity within a shared end-user IP range, other filtered content within the server IP range, whims of the government for enforcement, etc. etc.
We will be trying to support students there also. I guess we need to have a go, then let the Community know how we get on.