OpenSSH_4.3p1 configure patch

[Corinna Vinschen]

On Feb  7 01:06, Darren Tucker wrote:
> On Mon, Feb 06, 2006 at 02:42:55PM +0100, Corinna Vinschen wrote:
> > I just tested the below patch and it solves the problem for me.
> > Since session_exit_message is only called from session_close_by_pid,
> > the solution seems to be the correct one.
> > 
> > 
> > --- session.c.ORIG	2006-02-06 13:50:21.788927500 +0100
> > +++ session.c	2006-02-06 13:45:27.042081500 +0100
> > @@ -2176,7 +2176,6 @@ session_exit_message(Session *s, int sta
> >  
> >  	/* disconnect channel */
> >  	debug("session_exit_message: release channel %d", s->chanid);
> > -	s->pid = 0;
> >  
> >  	/*
> >  	 * Adjust cleanup callback attachment to send close messages when
> > @@ -2238,6 +2237,7 @@ session_close_by_pid(pid_t pid, int stat
> >  		session_exit_message(s, status);
> >  	if (s->ttyfd != -1)
> >  		session_pty_cleanup(s);
> > +	s->pid = 0;
> >  }
> 
> FWIW the s->pid bit was added in this change:
> 
> revision 1.308
> date: 2005/11/05 03:52:51;  author: djm;  state: Exp;  lines: +23 -14
>    - djm at cvs.openbsd.org 2005/10/10 10:23:08
>      [channels.c channels.h clientloop.c serverloop.c session.c]
>      fix regression I introduced in 4.2: X11 forwardings initiated after
>      a session has exited (e.g. "(sleep 5; xterm) &") would not start.
>      bz #1086 reported by t8m AT centrum.cz; ok markus@ dtucker@
> 
> Not sure what (if any) effect the diff would have on the case above.

I'm not *quite* sure if I analyzed that correctly, but AFAICS, it should
have no effect on the situation solved by the patch from 2005/11/05:

- session_exit_message is a static function which is exclusively called
  by session_close_by_pid.

- In session_exit_message, following the setting of s->pid to 0 are only
  two calls, channel_register_cleanup and chan_write_failed.

- channel_register_cleanup only marks session_close_by_channel to be run
  for the channel on cleanup, but it does not run this function immediately,
  nor does it itself depend on the setting of s->pid.

- chan_write_failed does also not depend on the setting of s->pid.

- On return from session_exit_message to session_close_by_pid,
  session_pty_cleanup is called with correct s->pid setting.

- s->pid is set to 0.

- In a later cleanup, session_close_by_channel is called and s->pid has
  the expected value of 0.

Did I miss something?


Corinna

-- 
Corinna Vinschen
Cygwin Project Co-Leader
Red Hat