Re: [PATCH] TTY: do not reset master's packet mode

From: Karel Zak
Date: Wed Feb 20 2013 - 08:19:53 EST

On Tue, Jan 15, 2013 at 11:26:22PM +0100, Jiri Slaby wrote:
> Now that login from util-linux is forced to drop all references to a
> TTY which it wants to hangup (to reach reference count 1) we are
> seeing issues with telnet. When login closes its last reference to the
> slave PTY, it also resets packet mode on the *master* side. And we
> have a race here.


> By this I am resurrecting an old bug, see References. We are hitting
> it regularly now, i.e. with updated util-linux, ergo login.
> Here, I am changing a behavior introduced back in 2.1 times. It would
> better have a long time testing before goes upstream.

It would be nice to found a quick way how to resolve this problem,
because telnet+login is broken now... and for end users it seems like
a regression.

Maybe the requirement (patch) to close all references to TTY before
hangup should reverted or we can make an exception in login(1) code to
keep TTY open when login(1) is executed with -h (as used by telned).

Karel Zak <kzak@xxxxxxxxxx>
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