Re: [PATCH 05/17] workqueue: cfi: disable callback pointer check with modules

From: Kees Cook
Date: Thu Mar 11 2021 - 21:43:54 EST


On Thu, Mar 11, 2021 at 04:49:07PM -0800, Sami Tolvanen wrote:
> With CONFIG_CFI_CLANG, a callback function passed to
> __queue_delayed_work from a module points to a jump table entry
> defined in the module instead of the one used in the core kernel,
> which breaks function address equality in this check:
>
> WARN_ON_ONCE(timer->function != delayed_work_timer_fn);
>
> Disable the warning when CFI and modules are enabled.

Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>

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Kees Cook