Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
MIME-Version: 1.0
References: <20200327192854.31150-1-kpsingh@chromium.org> <4e5a09bb-04c4-39b8-10d4-59496ffb5eee@iogearbox.net>
 <20200328195636.GA95544@google.com> <202003281449.333BDAF6@keescook>
In-Reply-To: <202003281449.333BDAF6@keescook>
From:   KP Singh <kpsingh@chromium.org>
Date:   Sat, 28 Mar 2020 23:30:13 +0100
Message-ID: <CACYkzJ4v_X87-+GCE++g0_BkcJWFhbNePAMQmH8Ccgq7id-akA@mail.gmail.com>
Subject: Re: [PATCH bpf-next v8 0/8] MAC and Audit policy using eBPF (KRSI)
To:     Kees Cook <keescook@chromium.org>
Cc:     Daniel Borkmann <daniel@iogearbox.net>,
        open list <linux-kernel@vger.kernel.org>,
        bpf <bpf@vger.kernel.org>,
        Linux Security Module list 
        <linux-security-module@vger.kernel.org>,
        Alexei Starovoitov <ast@kernel.org>,
        James Morris <jmorris@namei.org>, Paul Turner <pjt@google.com>,
        Jann Horn <jannh@google.com>,
        Florent Revest <revest@chromium.org>,
        Brendan Jackman <jackmanb@chromium.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Content-Type: text/plain; charset="UTF-8"
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Sat, Mar 28, 2020 at 10:50 PM Kees Cook <keescook@chromium.org> wrote:
>
> On Sat, Mar 28, 2020 at 08:56:36PM +0100, KP Singh wrote:
> > Since the attachment succeeds and the hook does not get called, it
> > seems like "bpf" LSM is not being initialized and the hook, although
> > present, does not get called.
> >
> > This indicates that "bpf" is not in CONFIG_LSM. It should, however, be
> > there by default as we added it to default value of CONFIG_LSM and
> > also for other DEFAULT_SECURITY_* options.
> >
> > Let me know if that's the case and it fixes it.
>
> Is the selftest expected to at least fail cleanly (i.e. not segfault)

I am not sure where the crash comes from, it does not look like it's test_lsm,
it seems to happen in test_overhead. Both seem to run fine for me.

- KP

> when the BPF LSF is not built into the kernel?
>
> --
> Kees Cook