Draw line within bounds of circular collider

Hello all!

I'm trying to draw a line within bounds of a circular object. I found some code online to draw line and with some edit I was able to limit the size of the line.

     private Vector3 pos1;
     private Vector3 pos2;
     public float objectHeight = 1.0f;
     public GameObject prefab;
 
     private GameObject go;
 
     private bool isBeingDrawn = false;
     private Collider2D collider2d;
 
     private void Start()
     {
         collider2d = GetComponent<Collider2D>();
     }
 
     private void OnMouseDown()
     {
         if (Input.GetMouseButtonDown(0))
         {
             pos1 = Camera.main.ScreenToWorldPoint(Input.mousePosition);
             pos1.z = -2f;
             pos2 = pos1;
 
             go = Instantiate(prefab, pos1, Quaternion.identity, GameObject.Find("empty").transform);
             Vector3 temp = go.transform.localScale;
             temp.y = 0.0f;
             go.transform.localScale = temp;
             isBeingDrawn = true;
         }
     }
 
     private void OnMouseUp()
     {
         isBeingDrawn = false;
     }
 
     void Update()
     {
         if (isBeingDrawn)
         {
             Vector3 pos = Camera.main.ScreenToWorldPoint(Input.mousePosition);
             if (pos.x < collider2d.bounds.extents.x && pos.y < collider2d.bounds.extents.y && pos.x > -collider2d.bounds.extents.x && pos.y > -collider2d.bounds.extents.y)
             {
                 pos2 = pos;
                 pos2.z = -2f;
             }
         }
 
         if (pos2 != pos1)
         {
             Vector3 v3 = pos2 - pos1;
             go.transform.position = pos1 + (v3) / 2.0f;
             go.transform.localScale = new Vector2(go.transform.localScale.x, v3.magnitude);
             go.transform.rotation = Quaternion.FromToRotation(Vector2.up, v3);
         }
     }

But the line still moves outside the circular object specially at the corners as you can see in the pictures.

How can I keep it within the collider bounds? any help is appreciated.