YES
A work permit is not a visa. It is the legal authorization for you to stay in Canada. However, according to the Government of Canada, you need an eTA or a visa, along with your work permit to enter Canada.
On a side note remember that a visa/eTA can expire while you are in Canada and itsit's okay as long as you are not planning to leave the country. You will need it only while reentering Canada. You will need a visa/eTA to enter Canada though. However, having a valid work permit is absolutely required for you to legally stay and work in Canada.
