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From:   Paul Moore <paul@paul-moore.com>
Date:   Mon, 17 Jul 2023 16:21:49 -0400
Message-ID: <CAHC9VhQFn1cE39YuXNxssttu1tU6oXWsYjGLSzD496Wa5-Gs5A@mail.gmail.com>
Subject: Re: [RFC PATCH] selinux: disable debug functions by default
To:     =?UTF-8?Q?Christian_G=C3=B6ttsche?= <cgzones@googlemail.com>
Cc:     selinux@vger.kernel.org,
        Stephen Smalley <stephen.smalley.work@gmail.com>,
        Eric Paris <eparis@parisplace.org>,
        linux-kernel@vger.kernel.org
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On Thu, Jul 6, 2023 at 9:37=E2=80=AFAM Christian G=C3=B6ttsche
<cgzones@googlemail.com> wrote:
>
> avtab_hash_eval() and hashtab_stat() are only used in policydb.c when
> the debug macro DEBUG_HASHES is defined.
>
> Signed-off-by: Christian G=C3=B6ttsche <cgzones@googlemail.com>
> ---
>  security/selinux/ss/avtab.c   | 2 ++
>  security/selinux/ss/avtab.h   | 3 +++
>  security/selinux/ss/hashtab.c | 3 ++-
>  security/selinux/ss/hashtab.h | 2 ++
>  4 files changed, 9 insertions(+), 1 deletion(-)

This reminds me that I don't really like the "hidden" and kludgy
nature of DEBUG_HASHES.  What if we created a proper SELinux debug
Kconfig flag and used it in place of DEBUG_HASHES?  I'm thinking of
something like this:

config SECURITY_SELINUX_DEBUG
  bool "NSA SELinux kernel debugging support"
  depends on SECURITY_SELINUX
  default n
  help
    This enables debugging code designed to help SELinux kernel developers,
    unless you know what this does in the kernel code you should leave this
    disabled.

... and then we do all of the usual Kconfig triggered dummy funcs,
etc.  Thoughts?

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paul-moore.com