Re: [PATCH 13/17] arm64: use __pa_function

From: Kees Cook
Date: Thu Mar 11 2021 - 21:47:39 EST


On Thu, Mar 11, 2021 at 04:49:15PM -0800, Sami Tolvanen wrote:
> With CONFIG_CFI_CLANG, the compiler replaces function address
> references with the address of the function's CFI jump table
> entry. This means that __pa_symbol(function) returns the physical
> address of the jump table entry, which can lead to address space
> confusion as the jump table points to the function's virtual
> address. Therefore, use the __pa_function() macro to ensure we are
> always taking the address of the actual function instead.
>
> Signed-off-by: Sami Tolvanen <samitolvanen@xxxxxxxxxx>

Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>

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Kees Cook