linux-kernel - Re: [kernel-hardening] Re: [PATCH v6 0/2] security: tty: make TIOCSTI ioctl require CAP_SYS

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20170519143344.GA15983@mail.hallyn.com>
Date:   Fri, 19 May 2017 09:33:44 -0500
From:   "Serge E. Hallyn" <serge@...lyn.com>
To:     Peter Dolding <oiaohm@...il.com>
Cc:     Kees Cook <keescook@...omium.org>,
        Daniel Micay <danielmicay@...il.com>,
        Alan Cox <gnomes@...rguk.ukuu.org.uk>,
        Matt Brown <matt@...tt.com>,
        "Serge E. Hallyn" <serge@...lyn.com>,
        Greg KH <gregkh@...uxfoundation.org>,
        Jiri Slaby <jslaby@...e.com>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Jann Horn <jannh@...gle.com>, James Morris <jmorris@...ei.org>,
        "kernel-hardening@...ts.openwall.com" 
        <kernel-hardening@...ts.openwall.com>,
        linux-security-module <linux-security-module@...r.kernel.org>,
        linux-kernel <linux-kernel@...r.kernel.org>
Subject: Re: [kernel-hardening] Re: [PATCH v6 0/2] security: tty: make
 TIOCSTI ioctl require CAP_SYS_ADMIN

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.