Change in X11 forwarding behaviour with OpenSSH 4.2p1

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there is a change in the behaviour of the X11 forwarding between versions
4.1 and 4.2. With 4.2 the following construct does not work any more:

[fuchur] ~ % ssh -f fuchur 'xterm &'
[fuchur] ~ % xterm Xt error: Can't open display: localhost:10.0

I know this example is a bit stupid. But the problem really shows up at
the following example:

[fuchur] ~ % ssh -f fuchur $script

where $script looks like this:

xterm &

Very often you cannot simply modify $script and therefor have to login and
start a shell before being able to launch $script.

I think this is related to the following entry in Changelog:

- OpenBSD CVS Sync
  - (djm) [auth-pam.c sftp.c] spaces vs. tabs at start of line
    - 2005/07/17 06:49:04
      [channels.c channels.h session.c session.h]
      Fix a number of X11 forwarding channel leaks:
      1. Refuse multiple X11 forwarding requests on the same session
      2. Clean up all listeners after a single_connection X11 forward, not
         the one that made the single connection
      3. Destroy X11 listeners when the session owning them goes away
      testing and ok dtucker@

Should it be considered as a bug?


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Re: Change in X11 forwarding behaviour with OpenSSH 4.2p1

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There's a patch attached to the bug which should fix it; please test and
(this is important) report your findings.  One-off tests are OK, thorough
tests (eg "we used it on our dev boxes for N days/weeks") are better.

Often patches do not get applied due to insufficient testing (or lack
of reports, which is indistiguishable from the developers' point of view).

Darren Tucker (dtucker at
GPG key 8FF4FA69 / D9A3 86E9 7EEE AF4B B2D4  37C9 C982 80C7 8FF4 FA69
    Good judgement comes with experience. Unfortunately, the experience
usually comes from bad judgement.

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