Follow @Openwall on Twitter for new release announcements and other news
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Wed, 31 May 2017 00:56:33 +0100
From: Alan Cox <gnomes@...rguk.ukuu.org.uk>
To: Matt Brown <matt@...tt.com>
Cc: Casey Schaufler <casey@...aufler-ca.com>,
        Boris Lukashev
 <blukashev@...pervictus.com>,
        Greg KH <gregkh@...uxfoundation.org>,
        "Serge
 E. Hallyn" <serge@...lyn.com>,
        Kees Cook <keescook@...omium.org>, kernel-hardening@...ts.openwall.com,
        linux-security-module
 <linux-security-module@...r.kernel.org>,
        linux-kernel
 <linux-kernel@...r.kernel.org>
Subject: Re: Re: [PATCH v7 2/2] security: tty: make
 TIOCSTI ioctl require CAP_SYS_ADMIN

> This is my point. Apps will continue to shoot themselves in the foot. Of course
> the correct response to one of these vulns is to not pass ttys across a
> security boundary. We have an opportunity here to reduce the impact of this bug
> class at the kernel level. 

Not really.

If you pass me your console for example I can mmap your framebuffer and
spy on you all day. Or I could reprogram your fonts, your keyboard, your
video mode, or use set and paste selection to write stuff. If you are
using X and you can't get tty handles right you'll no doubt pass me a
copy of your X file descriptor in which case I own your display, your
keyboard and your mouse and I don't need to use TIOCSTI there either.

There are so many different attacks based upon that screwup that the
kernel cannot defend against them. You aren't exactly reducing the impact.

Alan

Powered by blists - more mailing lists

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.