Zelda ocarina of time, whats the secret to this hole in the lost woods? the one with a cracked ceiling..?

Its the hole where u get the deku nut upgrade, the other one sells arrows 30 for 70 rupees. The ceiling is cracked and there is light coming thru, navi glows green near it which means there is a secret, I've tried bombchus but haven't hit it yet, what's thru the ceiling and how do I break it