You can use just about any 3m adhesive (Gorrilla snot).

1>Remove headliner, spray adhesive on roof, and then on headliner. Don't use too much...it will "ball" up and look like crap when it dries.
2>Wait for about 3-5 minutes (read can for exact time)
3>Begin re-installing headliner, making sure to spread the goo underneath as you go so as to not create bunching.
4>Drink a beer and enjoy your handy work!