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Date:   Mon, 9 Mar 2020 09:23:29 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Jiri Slaby <jslaby@suse.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Matthew Garrett <mjg59@google.com>,
        Andi Kleen <ak@linux.intel.com>,
        "Theodore Y . Ts'o" <tytso@mit.edu>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Petr Mladek <pmladek@suse.com>,
        Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
        Arnd Bergmann <arnd@arndb.de>,
        LKML <linux-kernel@vger.kernel.org>,
        Dmitry Vyukov <dvyukov@google.com>
Subject: Re: [PATCH v2] Add kernel config option for fuzz testing.
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On Mon, 9 Mar 2020 20:22:47 +0900
Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> wrote:

> I think that locking down individual thing using individual switch is an
> endless game of maintaining list of switches. When someone adds a code
> which should not be fuzzed, the author of that code or the maintainer of
> fuzzers will add a new switch for that code, and the maintainer of fuzzers
> forever has to follow new switches. I think that it is better to keep number
> of switches minimal until we have to split into fine grained switches.

Can't we add a "TESTING" or "FUZZING" lockdown switch, that keeps root from
executing things that shouldn't be fuzzed?

I highly doubt that a kernel developer would even think "this shouldn't be
fuzzed" when adding something. It's going to first be reported by the
fuzz testing anyway. Don't just push the burden to the kernel developers.

-- Steve