openssh unix dev - Sep 2001 - Debian bug #111744 - SSH 2.9p2-5 port-forwarded connection may fail to close cleanly

I've got this report (edited for clarity):

# As it happens, it is unique to tunneling.  I only have one protocol to
# test with tunnelling at present due to firewalling on the host I'm
# connecting to (rdp to a terminal server).
#
# When I try and telnet [host] 3389, it works fine, and I can disconnect
# as normal.  If I try the rdp client, I get this error:
#
# rdesktop: A Remote Desktop Protocol client.
# Version 1.0.0-pl19-6-6. Copyright (C) 1999-2000 Matt Chapman.
# See http://www.rdesktop.org/ for more information.
#
#  Connection successful.
# tcp_recv read: Success
# ERROR: expected DT, got 240
# disconnecting
#
# ...and *that's* when ssh won't exit cleanly.  I've done a netstat
-an
# | grep 3389, and there's no output there; I don't think the connect is
# still open, but perhaps something messy happens with the rdesktop
# connect, and it causes ssh to become confused?

 The command he's running is:

$ slogin -2 -X -C -lrichardp -L 3389:172.20.1.92:3389 ssh.optimation.co.nz

 Now, usually one would expect a message like the following if the ssh
couldn't end because it was still forewarding connections:

% Waiting for forwarded connections to terminate...
% The following connections are open:
%   #0 direct-tcpip: listening port 54321 for xantha port 9, connect
% from 127.0.0.1 port 2337 (t4 r1 i1/0 o16/0)

 However in this case that didn't happen.

 We are fairly sure that there is a bug in rdesktop - but even so ssh
should either exit or give that message in our opinion.

 Any suggestions?

 (The Debian BTS entry for this bug includes some strace output which
I could mail to this list if it was thought helpful).

 Thanks,

  Jonathan.

did you check netstat?

On Thu, Sep 13, 2001 at 07:54:55PM +0100, Jonathan Amery
wrote:
> 
>  I've got this report (edited for clarity):
> 
> # As it happens, it is unique to tunneling.  I only have one protocol to
> # test with tunnelling at present due to firewalling on the host I'm
> # connecting to (rdp to a terminal server).
> #
> # When I try and telnet [host] 3389, it works fine, and I can disconnect
> # as normal.  If I try the rdp client, I get this error:
> #
> # rdesktop: A Remote Desktop Protocol client.
> # Version 1.0.0-pl19-6-6. Copyright (C) 1999-2000 Matt Chapman.
> # See http://www.rdesktop.org/ for more information.
> #
> #  Connection successful.
> # tcp_recv read: Success
> # ERROR: expected DT, got 240
> # disconnecting
> #
> # ...and *that's* when ssh won't exit cleanly.  I've done a
netstat -an
> # | grep 3389, and there's no output there; I don't think the
connect is
> # still open, but perhaps something messy happens with the rdesktop
> # connect, and it causes ssh to become confused?
> 
>  The command he's running is:
> 
> $ slogin -2 -X -C -lrichardp -L 3389:172.20.1.92:3389 ssh.optimation.co.nz
> 
>  Now, usually one would expect a message like the following if the ssh
> couldn't end because it was still forewarding connections:
> 
> % Waiting for forwarded connections to terminate...
> % The following connections are open:
> %   #0 direct-tcpip: listening port 54321 for xantha port 9, connect
> % from 127.0.0.1 port 2337 (t4 r1 i1/0 o16/0)
> 
>  However in this case that didn't happen.
> 
>  We are fairly sure that there is a bug in rdesktop - but even so ssh
> should either exit or give that message in our opinion.
> 
>  Any suggestions?
> 
>  (The Debian BTS entry for this bug includes some strace output which
> I could mail to this list if it was thought helpful).
> 
>  Thanks,
> 
>   Jonathan.