Re: [PATCH v3 04/17] module: ensure __cfi_check alignment

From: Kees Cook
Date: Fri Mar 26 2021 - 00:35:20 EST


On Tue, Mar 23, 2021 at 01:39:33PM -0700, Sami Tolvanen wrote:
> CONFIG_CFI_CLANG_SHADOW assumes the __cfi_check() function is page
> aligned and at the beginning of the .text section. While Clang would
> normally align the function correctly, it fails to do so for modules
> with no executable code.
>
> This change ensures the correct __cfi_check() location and
> alignment. It also discards the .eh_frame section, which Clang can
> generate with certain sanitizers, such as CFI.
>
> Link: https://bugs.llvm.org/show_bug.cgi?id=46293
> Signed-off-by: Sami Tolvanen <samitolvanen@xxxxxxxxxx>

Yay macros! :)

Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>

--
Kees Cook