Sunroof (S/R) drains. There are two in the front corners of the sunroof well, and probably two in the back as well, but I can't see back there. Open the sunroof and see if there is water standing in the well. There shouldn't be any. If there is no standing water, you can check to see if the drains are clear by pouring some water in and watch if it drains. If it doesn't, your water probably just overflowed the sunroof well and got into the headliner. Clean out the drains, and you should be OK. The other possibility is that one of the drain hoses has become disconnected. You could only check this by removing the headliner. My Haynes manual says this job is best left up to the dealer. I've never tried it, so can't advise.