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Date: Fri, 19 May 2017 09:33:44 -0500
From: "Serge E. Hallyn" <serge@hallyn.com>
To: Peter Dolding <oiaohm@gmail.com>
Cc: Kees Cook <keescook@chromium.org>,
        Daniel Micay <danielmicay@gmail.com>,
        Alan Cox <gnomes@lxorguk.ukuu.org.uk>, Matt Brown <matt@nmatt.com>,
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Subject: Re: [kernel-hardening] Re: [PATCH v6 0/2] security: tty: make
 TIOCSTI ioctl require CAP_SYS_ADMIN
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On Fri, May 19, 2017 at 12:48:17PM +1000, Peter Dolding wrote:
> Using cap_sys_admin as fix is like removing car windsheld because
> vision is being blocked by a rock hitting it.

Nonsense.  If the application has cap_sys_admin then it is less contained and
more trusted anyway.  If I went to the trouble to run an application in a
private user namespace (where it can have cap_sys_admin, but not targeted
at my tty) then it should be more contained.  That's the point of targeted
capabilities.