It should be noted that the Soviet Union ended up winning that war.

WP says "Most sources conclude that the Soviet Union had intended to conquer all of Finland", acknowledging that some don't. And also offers the following tasty tidbit:

  "Commander Meretskov announced publicly that the Finnish campaign would take two weeks at the most. Soviet soldiers had even been warned not to cross the border into Sweden by mistake."

In any case the narrative I've always heard is that whatever its initial goals were -- the final outcome (and especially the amount of territory ceded) fell far short of those goals and at far greater cost than anticipated.

If you know of an analysis that (cogently) suggests otherwise, feel free to share it with us.