Could not find libc

[htjain]

getting following error while running on ubuntu docker image:

Traceback (most recent call last):
File "/usr/local/bin/madbg", line 8, in
sys.exit(cli())
File "/usr/local/lib/python3.8/dist-packages/click/core.py", line 1130, in call
return self.main(*args, **kwargs)
File "/usr/local/lib/python3.8/dist-packages/click/core.py", line 1055, in main
rv = self.invoke(ctx)
File "/usr/local/lib/python3.8/dist-packages/click/core.py", line 1657, in invoke
return _process_result(sub_ctx.command.invoke(sub_ctx))
File "/usr/local/lib/python3.8/dist-packages/click/core.py", line 1404, in invoke
return ctx.invoke(self.callback, **ctx.params)
File "/usr/local/lib/python3.8/dist-packages/click/core.py", line 760, in invoke
return __callback(*args, **kwargs)
File "/usr/local/lib/python3.8/dist-packages/madbg/main.py", line 34, in attach
attach_to_process(pid, port, connect_timeout=timeout)
File "/usr/local/lib/python3.8/dist-packages/madbg/api.py", line 34, in attach_to_process
_inject_set_trace(pid, ip, port)
File "/usr/local/lib/python3.8/dist-packages/madbg/api.py", line 28, in _inject_set_trace
inject_py(pid, f'import("signal").signal({sig_num},lambda _,f:import("madbg").set_trace(f,"{ip}",{port}))')
File "/usr/local/lib/python3.8/dist-packages/hypno/hypno.py", line 20, in inject_py
inject(pid, str(copied_lib))
File "/usr/local/lib/python3.8/dist-packages/pyinjector/pyinjector.py", line 95, in inject
injector = Injector.attach(pid)
File "/usr/local/lib/python3.8/dist-packages/pyinjector/pyinjector.py", line 77, in attach
call_c_func(libinjector.injector_attach, byref(injector_p), pid,
File "/usr/local/lib/python3.8/dist-packages/pyinjector/pyinjector.py", line 66, in call_c_func
raise exception_cls(func.name, ret, libinjector.injector_error())
pyinjector.pyinjector.InjectorError: injector_attach returned -4: Could not find libc

[kmaork]

Thank you for the report @htjain!
Can you provide more details? I tried recreating the issue by:

docker run -it python:latest bash
pip3 install madbg
python -c "while 1:1" &
madbg attach $!

And it worked for me.

I'd like to know:

1. How you installed madbg
2. How you invoked madbg
3. What version of the ubuntu image you were using
4. How you invoked the process you tried attaching to