Math.random() with do while loop sometimes hang the page

I am making a simple game where I need to generate an object 1: its position x and y needs to be in certain range 2: it must not overlap with some existing objects. I use the Math.random() and the do while loop for that, but the game intermittently crashes.

I cannot see any flaw in the logic, but why it crashes?

 let posX, posY;
 let invalid = false;
     do {
         posX = getRandomInt(0,100);
         posY = getRandomInt(0,100);
         if (posX > 20 &&
             posX < 40 &&
             posY > 20 &&
             posY < 40
            )
              invalid = true;
        }
        while (invalid)
 alert("not crash!")
 function getRandomInt(min, max) {
        min = Math.ceil(min);
        max = Math.floor(max);
        return Math.floor(Math.random() * (max - min + 1)) + min;
    }