Re: SSH channel forwarding fails on ieof

[Pugnator <ookami@xxxxxxx>]

It's a pity but it seems I was in hurry. The issue is still reproducing 
on some machines.
The error code is the same

channel_by_id: 0: bad id: channel free

But issue is not stable - reproduces on specific machines only


On 09/25/2013 04:27 AM, Pugnator wrote:
> Thanks a lot for your reply.
> Yes, it is the case for me as I'm creating multiple channels 
> simultaneously.
> I used stable repo from Debian 7. I followed your suggestion and 
> compiled 0.6rc.
> The issue was not reproduced after it.
>
>
> On 09/25/2013 12:36 AM, Aris Adamantiadis wrote:
> > Hi,
> >
> > Could you try again with libssh 0.5.5 or 0.6rc and tell me if you can
> > reproduce the problem ? This behaviour recalls me of a bug that has been
> > fixed in 0.5.3, and would happen when you open multiple channels. Is it
> > the case ?
> >
> > Thanks,
> >
> > Aris
> >
> > Le 24/09/13 18:21, Pugnator a écrit :
> > > I use libssh 0.5.2 binding for C under Linux. In my program I create 
> > > SSH
> > > tunnel to XenServer. It worked perfectly until I updated to the most
> > > recent XenServer 6.2. After it ssh tunneling started failing with
> > >
> > > [1] Analyzing banner: SSH-2.0-OpenSSH_4.3
> > > [1] We are talking to an OpenSSH client version: 4.3 (40300)
> > > [1] placing 18 bytes into channel buffer (stderr=0)
> > > [1] Error : Channel opening failure: channel 44 error (2) Connection
> > > refused
> > >
> > > On server side there is records in /var/log/secure:
> > >
> > > Sep 24 20:12:10 proxima sshd[20782]: pam_unix(sshd:session): session
> > > opened for user root by (uid=0)
> > > Sep 24 20:12:10 proxima sshd[20792]: Accepted password for root from
> > > 10.250.144.221 port 55673 ssh2
> > > Sep 24 20:12:10 proxima sshd[20792]: pam_unix(sshd:session): session
> > > opened for user root by (uid=0)
> > > Sep 24 20:12:11 proxima sshd[16132]: channel_by_id: 0: bad id: 
> > > channel free
> > > Sep 24 20:12:11 proxima sshd[16132]: Disconnecting: Received ieof for
> > > nonexistent channel 0.
> > > Sep 24 20:12:11 proxima sshd[16132]: pam_unix(sshd:session): session
> > > closed for user root
> > >
> > >
> > > The most strange is the ssh server version is the same on old and new
> > > servers:
> > > OpenSSH_4.3p2, OpenSSL 0.9.8e-fips-rhel5 01 Jul 2008
> > >
> > > I'm not sure how to debug such an issue. Sometimes tunnel establishes
> > > and works but it is 1 out of 100 tries.