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From:   Joel Fernandes <joelaf@google.com>
Date:   Tue, 28 Jul 2020 11:22:52 -0400
Message-ID: <CAJWu+orndyKTVTO-StUxnPsQ-TkbQHU5WxzOJ35EhckGfUzD1A@mail.gmail.com>
Subject: Re: [PATCH] selinux: add tracepoint on denials
To:     =?UTF-8?Q?Thi=C3=A9baud_Weksteen?= <tweek@google.com>
Cc:     Paul Moore <paul@paul-moore.com>, Nick Kralevich <nnk@google.com>,
        Stephen Smalley <stephen.smalley.work@gmail.com>,
        Eric Paris <eparis@parisplace.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        Ingo Molnar <mingo@redhat.com>,
        Mauro Carvalho Chehab <mchehab+huawei@kernel.org>,
        "David S. Miller" <davem@davemloft.net>,
        Rob Herring <robh@kernel.org>,
        LKML <linux-kernel@vger.kernel.org>, selinux@vger.kernel.org
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On Fri, Jul 24, 2020 at 5:15 AM Thi=C3=A9baud Weksteen <tweek@google.com> w=
rote:
>
> The audit data currently captures which process and which target
> is responsible for a denial. There is no data on where exactly in the
> process that call occurred. Debugging can be made easier by being able to
> reconstruct the unified kernel and userland stack traces [1]. Add a
> tracepoint on the SELinux denials which can then be used by userland
> (i.e. perf).
>
> Although this patch could manually be added by each OS developer to
> trouble shoot a denial, adding it to the kernel streamlines the
> developers workflow.
>
> [1] https://source.android.com/devices/tech/debug/native_stack_dump
>
> Signed-off-by: Thi=C3=A9baud Weksteen <tweek@google.com>
> Signed-off-by: Joel Fernandes <joelaf@google.com>

While I am in support of the general idea, could you change my SOB to
something like Inspired-by?

This is really your patch, but I did demonstrate the idea in an
article where the intention was to apply a patch out of tree to do
stack dumps / tracing.  SOB on the other hand is supposed to track the
flow of a patch (the people who the patch goes through) when it is
sent upstream.

Thanks,

 - Joel