user use mitm server to proxy ssh traffic(or any other unmitmable traffic)
mitm server determined that dont need mitm and go into copy tunnel logic
client begin sending handshake info but client crash abnomally
in this case,
client=>mitm connection will be close
but mitm => ssh server connection will be hang forever(ssh server still wait for reading handshake info, they dont know that client had already close the connection).
https://github.com/AdguardTeam/gomitmproxy/blob/8a052425e2d0fd70b17d278befadbfd8b5affc68/proxy.go#L549
consider this case.
in this case, client=>mitm connection will be close but mitm => ssh server connection will be hang forever(ssh server still wait for reading handshake info, they dont know that client had already close the connection).