could not accept SSL connection: Success

Hi all,

We've noticed the following connection error logs recently:

sql_error_code = XX000 LOG: could not accept SSL connection: Success

We're seeing this on PostgreSQL databases running on Ubuntu Focal 20.04 with
different PostgreSQL versions (13.5, 13.4, 12.9, 10.19...).

After going through the source code I think that this comes from a
`SSL_ERROR_SYSCALL` where the errcode itself is 0, given the "Success" error
that's getting logged.

The server is accepting other (TLSv1.3) SSL connections from the same source
around the same time when this happens, so I understand this error/behavior
is
likely due to the client itself closing the connection.

I saw previous discussions where different errors were logged with the
"Success"
message and this was corrected/treated as a bug, but I couldn't find similar
reports specific to "could not accept SSL connection". Is this a known
issue or
case?

Regards,
Carla