Citizenship is not a protected right under the Charter of Rights, it is not even mentioned in it, unless you broadly (and I mean very very broadly) interpret the right to non discrimination based on nationality. Even then, you could pass a law that would spell out conditions under which the government must take away a Canadian's citizenship, those conditions under which it could be taken away, including factors that the government then has to consider in good faith, and that would automatically create equality of treatment under the law and thus be in conformity with that section of the Charter.
Citizenship, however is protected under an international treaty to which just about everyone on the planet is party, aimed at eliminating or greatly reducing the number of stateless people in the world. Under that treaty , to which Canada and the UK are party, signatories have agreed that they will not strip someone of their citizenship if the result is that they become stateless people. That BTW is why the UK, which was faster than Canada in the matter, could strip Letts of his British citizenship - because he remained someone with citizenship after their action: he was still Canadian. A law adopted as described in my paragraph above would still have to meet all the requirements of that international treaty since it has been incorporated into Canadian law by Parliament.