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Date:   Wed, 20 Apr 2022 15:28:20 -0700
From:   Joao Moreira <joao@overdrivepizza.com>
To:     Kees Cook <keescook@chromium.org>
Cc:     linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org,
        peterz@infradead.org, jpoimboe@redhat.com,
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        alyssa.milburn@linux.intel.com, ndesaulniers@google.com,
        gabriel.gomes@linux.intel.com, rick.p.edgecombe@intel.com
Subject: Re: [RFC PATCH 11/11] driver/int3400_thermal: Fix prototype matching
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 <202204191946.2843CF71@keescook>
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> Where/why is the mismatch happening?

Mismatch happens in dev_attr_show from drivers/base/core.c. There, 
kobject * is cast to device * before the call, probably because attr is 
also cast to device_attribute, which may have a mismatching hook 
prototype, I guess.

I haven't tried it with any other CFI scheme other than my own 
implementation and I did not run this on GDB or anything... I'm just 
reporting based on the violation that FineIBT logged and in the fact 
that this patch fixed it, so I'm unsure if there is anything buried 
here.