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Date:   Mon, 2 Mar 2020 11:08:02 -0800
From:   Kees Cook <keescook@chromium.org>
To:     Kristen Carlson Accardi <kristen@linux.intel.com>
Cc:     Jann Horn <jannh@google.com>, Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        "H . Peter Anvin" <hpa@zytor.com>,
        Arjan van de Ven <arjan@linux.intel.com>,
        Rick Edgecombe <rick.p.edgecombe@intel.com>,
        the arch/x86 maintainers <x86@kernel.org>,
        kernel list <linux-kernel@vger.kernel.org>,
        Kernel Hardening <kernel-hardening@lists.openwall.com>
Subject: Re: [RFC PATCH 09/11] kallsyms: hide layout and expose seed
Message-ID: <202003021107.38017F90@keescook>
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On Mon, Mar 02, 2020 at 11:01:56AM -0800, Kristen Carlson Accardi wrote:
> On Thu, 2020-02-06 at 20:27 +0100, Jann Horn wrote:
> > https://codesearch.debian.net/search?q=%2Fproc%2Fkallsyms&literal=1
> 
> I looked through some of these packages as Jann suggested, and it seems
> like there are several that are using /proc/kallsyms to look for
> specific symbol names to determine whether some feature has been
> compiled into the kernel. This practice seems dubious to me, knowing
> that many kernel symbol names can be changed at any time, but
> regardless seems to be fairly common.

Cool, so a sorted censored list is fine for non-root. Would root users
break on a symbol-name-sorted view? (i.e. are two lists needed or can we
stick to one?)

-- 
Kees Cook