Is there any difference between posting something on my own website and posting it in Canvas?

Yes. Canvas, like many learning management systems (LMS), is password protected and accessible only by students enrolled in a particular course. A publicly accessible website is accessible by the whole world. SFU's Fair Dealing Policy (Application of Fair Dealing Under Policy R30.04), detailed in the Copyright and Teaching Infographic, provides parameters for making copyright protected materials available to your students, but specifically limits you to handing materials out in class, emailing them directly to your students, posting them in an LMS or including them in a course pack produced by the Bookstore. This policy is based on the fair dealing right in Canada's Copyright Act; wider distribution, such as on an open website, is generally considered less "fair." Additionally, some of the Library's subscriptions to ejournals and ebooks specifically permit articles and other materials to be posted only in restricted course management systems.