Bug 2467

Summary: point-to-point Tunnel doen't work since 6.8
Product: Portable OpenSSH Reporter: Daniel Heule <nerve>
Component: sshdAssignee: Assigned to nobody <unassigned-bugs>
Status: CLOSED WORKSFORME    
Severity: major CC: djm
Priority: P5    
Version: 7.1p1   
Hardware: amd64   
OS: Linux   
Attachments:
Description Flags
Debug log of the ssh client for a point-to-point session which dies if some traffic comes. none

Description Daniel Heule 2015-09-14 23:07:34 AEST 
Since sshd version 6.8, point-to-point tunnels doesn't work as soon as traffic through this tunnel ocures.

Steps to reproduce:
1. Use sshd > 6.7 on target server
2. open a point-to-point tunnel e.g. "ssh -w 10:10 targetserver.domain.org"
3. configure ip and link on tun10 on both sides
4. make some traffic, for example wget some file over the tunnel.
5. see the broken pipe

The debug log from client side is big, so i will upload it to the message.

The relevant log file on the server side:
Sep 14 14:44:56 serverhost sshd[23455]: channel 0: adjust 99528 overflows remote window 4294869275

The point-to-point works fine if i downgrade the server to 6.7p1

Please fix this bug, as i need the point-to-point tunnel feature.

Thank you,
Daniel
Comment 1 Daniel Heule 2015-09-14 23:23:01 AEST 
Created attachment 2705 [details]
Debug log of the ssh client for a point-to-point session which dies if some traffic comes.
Comment 2 Daniel Heule 2015-09-14 23:24:08 AEST 
The debug log is from 6.9, but i have also tested all versions up to 7.1p1, all have the same bug.
Comment 3 Damien Miller 2015-10-06 08:57:32 AEDT 
OpenSSH doesn't include this message:

debug2: tcpwinsz: 912000 for connection: 3

Can you reproduce the problem using an OpenSSH without third-party patches?
Comment 4 Daniel Heule 2015-10-08 02:28:06 AEDT 
After some tests, I have found out that this 
error is only triggerd if openssh was compiled with the hpnssh patch.

Sorry that I did not verify that before.

Thank you,
Daniel
Comment 5 Damien Miller 2016-08-02 10:41:47 AEST 
Close all resolved bugs after 7.3p1 release