You have a right to be protected from warrantless searches of your home with very limited exceptions. Your home is arguably the most protected place under the United States Constitution. Without some sort of exigent circumstances (police/life/death emergency), law enforcement should not be allowed to search your home without a warrant.
However, if you consented to the search, then you gave up that right. Whether the officer is operating under a valid warrant or consent, any contraband found can be used for charges against you. Connecting the contraband to a specific person in the home may be a challenge for law enforcement and the prosecuting agency unless someone makes an admission of guilt or there is some hard evidence connecting the contraband to a specific person.