OpenSSH_4.3p1 configure patch

[Corinna Vinschen]

On Feb  6 13:44, Corinna Vinschen wrote:
> On Feb  6 22:38, Darren Tucker wrote:
> > On Mon, Feb 06, 2006 at 12:02:43PM +0100, Corinna Vinschen wrote:
> > [...]
> > > I debugged an sshd child and found this:
> > > 
> > >   - On logging out from an interactive session, EOF is encountered and
> > >     down from do_authenticated, session_close_by_pid is called.
> > > 
> > >   - session_by_pid returns the correct Session pointer.
> > > 
> > >   - s->chanid is != -1, ==> session_exit_message is called.
> > > 
> > >   - session_exit_message sets s->pid = 0 and returns to session_close_by_pid.
> > > 
> > >   - s->ttyfd != -1, ==> session_pty_cleanup is called.
> > > 
> > >   - session_pty_cleanup calls session_pty_cleanup2.
> > > 
> > >   - In session_pty_cleanup2, record_logout is only called if s->pid != 0.
> > > 
> > > Do I miss something or is it somehow impossible to get a logout record
> > > this way?!?
> > 
> > When privsep is on, session_exit_message is called in the slave, but
> > session_pty_cleanup2 is called by the monitor, so it works.
> > 
> > It looks like a problem when privsep=no, though, and it's not immediately
> > obvious to me what to do with it.
> 
> This also happens if UsePrivilegeSeparation is set to "yes" in
> /etc/sshd_config on Cygwin.  The problem is that descriptor passing
> doesn't work on Cygwin which in turn sets use_privsep to 0.  So, logout
> logging is entirely broken for all systems which either don't support,
> or have broken file descriptor passing.
> 
> Since the old session_exit_message only set s->chanid to -1, maybe we
> could remove setting s->pid to 0 from session_exit_message and move it
> to the end of session_close_by_pid?

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.


Corinna

--- 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;
 }
 
 /*