While the odd were very long and the Finns put up one hell of a fight, it was not a victory. They gave the Reds the entire Karelian Isthmus, and a large block of land North of Lake Ladoga, including the second largest city in Finland.
All tolled the Finns lost 11% of their territory and 30% of their industrial capacity to the Reds.
...and thousand of people.
It was a defense victory for the Finns. They were 3 million people and even the land they were left with is larger than Italy. They weren’t forced under communism and massacred. The people left on the lost territory escaped to Finland. Finland is now one of the richest countries in the world.