[{CMA:{stockMarket:[{name:"name1",userStock:[1,2,3]},{name:"name2",userStock:[1,2,3]},{name:"name3",userStock:[1,2,3]}]}}]

db.collection.update({},{"$inc":{"CMA.stockMarket.$[elem1].userStock.2":5}},{arrayFilters:[{"elem1.name":"name2"}],"multi":false,"upsert":false})