ssh-add -l hangs under cygwin test 3.6.0-0.139.g...

[Norton Allen]

On 6/29/2024 8:21 PM, Norton Allen via Cygwin wrote:
>
> On 6/29/2024 5:29 PM, Brian Inglis via Cygwin wrote:
>> On 2024-06-29 14:20, Norton Allen via Cygwin wrote:
>>> On 6/29/2024 1:39 AM, Brian Inglis via Cygwin wrote:
>>>> Installed cygwin test to try to diagnose another issue - but not 
>>>> involved there.
>>>> Attempting to cygport upload - just hung without start ftp connection.
>>>> Reran cygport --debug upload and command hanging was ssh-add -l!
>>>> Confirmed by rerunning command ssh-add -l from bash.
>>>> Killed eventually with series of ctrl-C and ctrl-\.
>>>> Reran under strace and output log attached.
>>>> No version or help output from ssh-add so:
>>>> $ ssh -V
>>>> OpenSSH_9.7p1, OpenSSL 3.0.14 4 Jun 2024
>>>> After running setup and reinstalling 3.5.3, ssh-add -l works 
>>>> normally, and cygport upload succeeds to ftp package.
>>>> Only variable was the cygwin version installed.
>>
>>> I have experienced otherwise inexplicable hangs of ssh that have 
>>> been resolved by killing ssh-agent and restarting it. This doesn't 
>>> happen very often, so it is usually mystifying when it does occur -- 
>>> until I remember.
>>
>> I have *NEVER* had *ANY* issues using (Open)ssh etc. for remote 
>> login, shell, commands, file trees, or git (and earlier vcs) access, 
>> professionally and personally, over many years, releases, and 
>> systems, mainly from Cygwin/-X shells and sessions (due to using 
>> mainly Windows desktops with various Unix servers), with/out 
>> authorized_keys, passphrases, and/or keychain, until these recent 
>> instances under the test build.
>>
> I'm not above suspecting my problems arise from something unique in my 
> setup, but it hasn't occurred often enough for me to investigate further.
>
It wasn't clear to me whether your problem was readily reproducible. You 
repeated the ssh-add command, and it hung, but you didn't report having 
killed ssh-agent. If it was actually ssh-agent that was hung, I would 
absolutely expect ssh or ssh-add to hang trying to talk to it.