Date:   Tue, 16 Nov 2021 10:41:49 -0800
From:   Kees Cook <keescook@chromium.org>
To:     Alexander Popov <alex.popov@linux.com>
Cc:     Steven Rostedt <rostedt@goodmis.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Lukas Bulwahn <lukas.bulwahn@gmail.com>,
        Jonathan Corbet <corbet@lwn.net>,
        Paul McKenney <paulmck@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Peter Zijlstra <peterz@infradead.org>,
        Joerg Roedel <jroedel@suse.de>,
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        Muchun Song <songmuchun@bytedance.com>,
        Viresh Kumar <viresh.kumar@linaro.org>,
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Subject: Re: [PATCH v2 0/2] Introduce the pkill_on_warn parameter
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On Tue, Nov 16, 2021 at 12:12:16PM +0300, Alexander Popov wrote:
> What if the Linux kernel had a LSM module responsible for error handling policy?
> That would require adding LSM hooks to BUG*(), WARN*(), KERN_EMERG, etc.
> In such LSM policy we can decide immediately how to react on the kernel error.
> We can even decide depending on the subsystem and things like that.

That would solve the "atomicity" issue the WARN tracepoint solution has,
and it would allow for very flexible userspace policy.

I actually wonder if the existing panic_on_* sites should serve as a
guide for where to put the hooks. The current sysctls could be replaced
by the hooks and a simple LSM.

-- 
Kees Cook