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Subject: opp_get_notifier() needs to be under rcu_lock?
From: Kees Cook <keescook@chromium.org>
To: MyungJoo Ham <myungjoo.ham@samsung.com>
Cc: LKML <linux-kernel@vger.kernel.org>,
        Serge Hallyn <serge.hallyn@canonical.com>
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Hi,

It looks like find_device_opp() (called from opp_get_notifier()) needs
to be under RCU read lock, but this doesn't seem to be happening in
drivers/devfreq/devfreq.c. Doesn't this run the risk of referencing a
freed variable?

Thanks,

-Kees

-- 
Kees Cook
Chrome OS Security