Re: [PATCH v19 19/25] mm: Re-introduce vm_flags to do_mmap()

From: Kees Cook
Date: Thu Feb 04 2021 - 15:31:55 EST


On Wed, Feb 03, 2021 at 02:55:41PM -0800, Yu-cheng Yu wrote:
> There was no more caller passing vm_flags to do_mmap(), and vm_flags was
> removed from the function's input by:
>
> commit 45e55300f114 ("mm: remove unnecessary wrapper function do_mmap_pgoff()").
>
> There is a new user now. Shadow stack allocation passes VM_SHSTK to
> do_mmap(). Re-introduce vm_flags to do_mmap(), but without the old wrapper
> do_mmap_pgoff(). Instead, make all callers of the wrapper pass a zero
> vm_flags to do_mmap().
>
> Signed-off-by: Yu-cheng Yu <yu-cheng.yu@xxxxxxxxx>

Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>

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Kees Cook