Stuck on "SSH password" prompt

[ansibleguy]

Greetings.

Version: 2.4.0 and 2.3.6 (at least)

If we supply passwords (ssh, become and vault) it gets stuck at the SSH prompt.

We bascially supply the secrets like this:

args['ssh_key'] = creds.ssh_key
args['passwords'] = {}
args['passwords'][r'^SSH\s[pP]assword:\s*$'] = creds.connect_pass
args['passwords'][r'^BECOME\s[pP]assword:\s*$'] = creds.become_pass
args['passwords'][r'^Vault\s[pP]assword:\s*$'] = creds.vault_pass
RunnerConfig(**args)

I've debugged it and the password is actually sent here: https://github.com/ansible/ansible-runner/blob/2.4.0/src/ansible_runner/runner.py#L321

But the execution is stuck forever (not even a timeout?) at this point.

I've tried adding \r\n to the password and even using pexpect's sendcontrol - but without any change.
If another sendline is performed directly after the SSH prompt - it is unstuck. But the next prompt fails as it seems this empty-input is used for that one..

I've got it working for now as seen in this fork: https://github.com/ansibleguy/ansible-runner/blob/release_2.4/src/ansibleguy_runner/runner.py#L323
But that solution is not really clean.

[ansibleguy]

Related: #534, ansibleguy/webui#70

[ansibleguy]

Has occurred on multiple systems.