How do I debug a shared library using CLion ?

I am trying to Attach to a process using CLion like one does in VS to debug a .dll . But I need to debug a .so on Linux (I am using Ubuntu 18.04). Unfortunately my .so is a plugin to a different binary software I don't hold the source. Is it possible to attach to and debug the .so like one does on Windows+VS to debug a .dll ?

So far, I got :

Operation not permitted
Debugger detached