How do I Make a sprite follow the mouse to a certain point.

Hi ,

I am currently making a kinda of stealh/horror shooter with a flashlight on the gun . I want the aiming to work by mouse but not stretch the light all over the screen only like max 400 pixels away from the players. So it moves with the mouse but only to a certain point far away from the player. At the moment the light just moves all over.

Thanks!