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References: <20221115175652.3836811-1-roberto.sassu@huaweicloud.com> <20221115175652.3836811-4-roberto.sassu@huaweicloud.com>
In-Reply-To: <20221115175652.3836811-4-roberto.sassu@huaweicloud.com>
From:   Paul Moore <paul@paul-moore.com>
Date:   Tue, 15 Nov 2022 21:27:02 -0500
Message-ID: <CAHC9VhTA7SgFnTFGNxOGW38WSkWu7GSizBmNz=TuazUR4R_jUg@mail.gmail.com>
Subject: Re: [RFC][PATCH 3/4] lsm: Redefine LSM_HOOK() macro to add return
 value flags as argument
To:     Roberto Sassu <roberto.sassu@huaweicloud.com>
Cc:     ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org,
        martin.lau@linux.dev, song@kernel.org, yhs@fb.com,
        john.fastabend@gmail.com, kpsingh@kernel.org, sdf@google.com,
        haoluo@google.com, jolsa@kernel.org, revest@chromium.org,
        jackmanb@chromium.org, jmorris@namei.org, serge@hallyn.com,
        bpf@vger.kernel.org, linux-security-module@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Roberto Sassu <roberto.sassu@huawei.com>,
        stable@vger.kernel.org
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On Tue, Nov 15, 2022 at 12:58 PM Roberto Sassu
<roberto.sassu@huaweicloud.com> wrote:
>
> From: Roberto Sassu <roberto.sassu@huawei.com>
>
> Define four return value flags (LSM_RET_NEG, LSM_RET_ZERO, LSM_RET_ONE,
> LSM_RET_GT_ONE), one for each interval of interest (< 0, = 0, = 1, > 1).
>
> Redefine the LSM_HOOK() macro to add return value flags as argument, and
> set the correct flags for each LSM hook.
>
> Implementors of new LSM hooks should do the same as well.
>
> Cc: stable@vger.kernel.org # 5.7.x
> Fixes: 9d3fdea789c8 ("bpf: lsm: Provide attachment points for BPF LSM programs")
> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
> ---
>  include/linux/bpf_lsm.h       |   2 +-
>  include/linux/lsm_hook_defs.h | 779 ++++++++++++++++++++--------------
>  include/linux/lsm_hooks.h     |   9 +-
>  kernel/bpf/bpf_lsm.c          |   5 +-
>  security/bpf/hooks.c          |   2 +-
>  security/security.c           |   4 +-
>  6 files changed, 466 insertions(+), 335 deletions(-)

Just a quick note here that even if we wanted to do something like
this, it is absolutely not -stable kernel material.  No way.

-- 
paul-moore.com