Who does actually control the wolfswood, Starks or Glovers? We know that Starks regularly hunt there, so do you think they have some exclusive rights, or do you think that it is split?

Well, keep in mind that since the Glovers are masterly rather than lordly, the Starks have all kinds of rights and jurisdictions over the wolfswood that they would not have it was otherwise. So that might be the reason the Starks have the use of the wolfswood. 

Or it could be written into the feudal contract itself, that the Starks get to hunt in the woods. Feudal contracts were full of that stuff, with rents being paid in pheasants and horses and so on.