Date: Wed, 3 Jan 2018 14:08:08 -0500
From: Tom Horsley <horsley1953@gmail.com>
To: Kees Cook <keescook@chromium.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Laura Abbott <labbott@redhat.com>,
        David Howells <dhowells@redhat.com>,
        James Morris <james.l.morris@oracle.com>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] exec: Weaken dumpability for secureexec
Message-ID: <20180103140808.0215ac87@tomh>
In-Reply-To: <CAGXu5jJfqWJG=kk+dkd+p2Tb0AvX2Cve0cCFjC+xYraZZQTzQw@mail.gmail.com>
References: <20180102232133.GA39880@beast>
        <20180103070622.GA6950@mail.hallyn.com>
        <CAGXu5jJfqWJG=kk+dkd+p2Tb0AvX2Cve0cCFjC+xYraZZQTzQw@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org

On Wed, 3 Jan 2018 09:21:16 -0800
Kees Cook wrote:

> The more interesting thing here is that secureexec is set for a
> process that ISN'T actually setuid. (ptrace of a setuid process). I
> think tha'ts the real bug, but not something I'm going to be able to
> fix quickly. So, for now, I want to revert this, then try to fix the
> weird case, and see if that breaks anyone, then fix this back to
> secureexec.

Certainly a program file that has capabilities attached to it
via "setcap" is intended to be treated just like setuid if
the capabilities it has are a superset of the capabilities
of the debugger. (I don't know if that is a useful info in this
case, but I thought I'd mention it :-).