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From:   Kees Cook <keescook@chromium.org>
Date:   Wed, 14 Feb 2018 09:51:17 -0800
Message-ID: <CAGXu5jKtEv-W3R-uakY9S9=OFmjY3ZqxQJFa3YxGd4RWyUEGgQ@mail.gmail.com>
Subject: Re: [RFC PATCH ghak21 1/4] audit: make ANOM_LINK obey audit_enabled
 and audit_dummy_context
To:     Richard Guy Briggs <rgb@redhat.com>
Cc:     Linux-Audit Mailing List <linux-audit@redhat.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Eric Paris <eparis@redhat.com>,
        Paul Moore <paul@paul-moore.com>,
        Steve Grubb <sgrubb@redhat.com>
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On Wed, Feb 14, 2018 at 8:18 AM, Richard Guy Briggs <rgb@redhat.com> wrote:
> Audit link denied events emit disjointed records when audit is disabled.
> No records should be emitted when audit is disabled.
>
> See: https://github.com/linux-audit/audit-kernel/issues/21
> Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
> ---
>  kernel/audit.c | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/kernel/audit.c b/kernel/audit.c
> index 227db99..4c3fd24 100644
> --- a/kernel/audit.c
> +++ b/kernel/audit.c
> @@ -2261,6 +2261,9 @@ void audit_log_link_denied(const char *operation, const struct path *link)
>         struct audit_buffer *ab;
>         struct audit_names *name;
>
> +       if (!audit_enabled || audit_dummy_context())
> +               return;
> +
>         name = kzalloc(sizeof(*name), GFP_NOFS);
>         if (!name)
>                 return;

Doesn't this means errors here would be silent if audit isn't enabled?
I don't that; sysadmins should see this notification regardless of the
audit state...

-Kees

-- 
Kees Cook
Pixel Security