Is there a permanent fix for my hardwood floor buckling?
Most of the time there are only two causes for a buckling floor:


Moisture
No Expansion


To elaborate, if the flooring material is real hardwood vs laminate and you are cleaning it with a mop, then you are using too much water. A Swiffer wet jet is plenty. Another reason for excess water would be from below, such as cracks in the concrete, or a plumbing leak. 

As for the expansion, whether engineered or solid Hardwood, there should be about 1/2" expansion around the entire edge of the floor. Usually Quarter Round (wood trims) covers this gap between the wood and the wall. Sometimes the baseboard can cover this gap as well. If the expansion is not there, when the wood expands and contracts due to weather it will press up against the wall and buckle at its weakest point. This could be in the middle of the floor. 

Most of the time expansion is the culprit. The fix would be to pull up the trim around the edge and see if there is adequate expansion. 

This applies even with floating floors.