There are a lot of ways they can do it. Indirectly, they can appoint a board of directors, as China has done with South China Morning Post. Jack Ma, the founder of Alibaba, bought the South China Morning Post and appointed a pro-China board of directors. As a result, they have practically shut down a once august English-language publication in Hong Kong.
They can do that to any Canadian company. It's just a matter of a takeover. It doesn't even have to be Chinese citizens. It could be Canadian citizens who might be pro-China or would be sympathetic to Chinese requirements. These are the national security and economic interests that are in jeopardy.