Make use of the constitutional system. It can impeach and remove justices. It can increase or decrease the size of the court itself (at its inception, the Supreme Court had only six members). It can strip the court of its jurisdiction over certain issues or it can weaken its power of judicial review by requiring a supermajority of justices to sign off on any decision that overturns a law. Congress can also rebuke the court with legislation that simply cancels the decision in question.
There are things that can be done.