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From:   David Laight <David.Laight@ACULAB.COM>
To:     'Samuel Thibault' <samuel.thibault@ens-lyon.org>,
        Kees Cook <keescook@chromium.org>
CC:     Kees Cook <kees@kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Jiri Slaby <jirislaby@kernel.org>,
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        "linux-hardening@vger.kernel.org" <linux-hardening@vger.kernel.org>,
        "Dave@mielke.cc" <Dave@mielke.cc>
Subject: RE: [PATCH v3 2/2] tty: Allow TIOCSTI to be disabled
Thread-Topic: [PATCH v3 2/2] tty: Allow TIOCSTI to be disabled
Thread-Index: AQHZqZu1MI//nXKQnEKNH07rOK4tp6+hxWvQ
Date:   Thu, 29 Jun 2023 13:23:54 +0000
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From: Samuel Thibault
> Sent: 28 June 2023 07:07
...
> > So is there really no solution for brltty and TIOCSTI being disabled?
> 
> No, there is no way to simulate characters on the Linux console. The
> alternative would be to use uinput, but that simulates keycodes, not
> characters, thus requiring backtranslating first, which is very fragile.

It could probably be rewritten to use a pseudo-tty pair.
It might even be possible to emulate (the functionality of) TIOCSTI
in the relay process that handles the pseudo-tty.

	David

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