This is the mail archive of the cygwin mailing list for the Cygwin project.

Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: Sshd: problem with X11 passthru

On Mar 28 10:17, David Picton wrote:
> >From: Corinna Vinschen <corinna-cygwin at cygwin dot com>
> >On Mar 27 18:55, David Picton wrote:
> >> I have encountered a problem with the sshd server when the client
> >> specifies X11 passthru i.e. ssh -Y or ssh -X.
> >>
> >> The allocation of virtual displays doesn't work correctly if two or
> >> more X11-enabled sessions run at the same time.
> >>
> >> As I understand it, the server should give each session a unique
> >> display number under these circumstances:  localhost:10.0,
> >> localhost:11.0, localhost:12.0 etc.
> >>
> >> Instead, all the sessions have DISPLAY=localhost:10.0 at the same
> >> time.  This causes a variety of problems - loss of access to the X
> >> server (due to changed Magic Cookie authorization on the server when a
> >> new client connects), or the appearance of windows on the wrong server
> >> (if two different clients connect).
> >>
> >> (Note that setting up Magic Cookie authorization on the client machine
> >> makes no difference to this bug.  It prevents the client-side warning
> >> about 'fake authorization' but it doesn't cure any of the server-side
> >> problems!)
> >
> >I don't see anything Cygwin specific here.  You should ask your
> >question on a mailing list or newsgroup dedicated to OpenSSH.
> Apologies for not making it clear that I was talking about the Cygwin
> port of sshd.
> The bug seems to be specific to the Cygwin version and I've not seen it on other

Well, the problem is this.  I just tried it and I can't reproduce it.
Each session gets another display number, starting at 10, as expected.
Maybe this is somehow due to a sshd_config setting which uncovers a
sshd problem?  I don't see how this should be related to Cygwin.  I still
think this should be a question for a ssh mailing list.


Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Project Co-Leader          cygwin AT cygwin DOT com
Red Hat

Unsubscribe info:
Problem reports:

Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]