Re: [PATCH] Ensure that SSH runs in non-interactive mode

> On Sun, Jul 20, 2008 at 11:23:13AM -0700, Junio C Hamano wrote:
> 
> > I think that is a very sensible approach, but just like we have a few
> > "built-in" function-header regexps with customization possibilities for
> > the user, we might want to:
> > 
> >  * Have that "-x", "-T" in the command line we generate for OpenSSH;
> 
> I am slightly negative on this, because we are setting OpenSSH
> preferences behind the user's back that they would not normally expect
> git to be tampering with.
> 
> I think the expectation for this is that it impacts only the ssh session
> used by git.  But because OpenSSH supports the concept of "master" and
> "slave" sessions (i.e., it can multiplex many sessions over a single ssh
> session, avoiding authentication and thus reducing latency until the
> start of the session), what you do in one session can impact other
> sessions. In particular, if the 'master' does not have x11 forwarding
> (because it happens to be started by git), then slave connections do not
> get it. So a user with X11Forwarding and ControlMaster set in his config
> would usually have everything work, but bad timing with the
> git-initiated session as the master would unexpectedly break his
> X11Forwarding for other sessions.
> 
> I don't know how commonly the ControlMaster option for openssh is used.
> I also don't know if this should simply be considered a bug in openssh,
> since it silently ignores the request for X forwarding.  Personally, I
> will not be affected because I don't do X forwarding by default, anyway.
> But I thought I would raise the point.