Re: [edk2-devel] [Patch V5 02/14] MdeModulePkg: Remove RO and NX protection when unset guard page

["Ard Biesheuvel" <ardb@kernel.org>]

On Thu, 8 Jun 2023 at 04:28, duntan <dun.tan@intel.com> wrote:
>
> Remove RO and NX protection when unset guard page.
> When UnsetGuardPage(), remove all the memory attribute protection
> for guarded page.
>

Why is it acceptable to remove NX protections here?


> Signed-off-by: Dun Tan <dun.tan@intel.com>
> Cc: Liming Gao <gaoliming@byosoft.com.cn>
> Cc: Ray Ni <ray.ni@intel.com>
> Cc: Jian J Wang <jian.j.wang@intel.com>
> ---
>  MdeModulePkg/Core/PiSmmCore/HeapGuard.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/MdeModulePkg/Core/PiSmmCore/HeapGuard.c b/MdeModulePkg/Core/PiSmmCore/HeapGuard.c
> index 8f3bab6fee..7daeeccf13 100644
> --- a/MdeModulePkg/Core/PiSmmCore/HeapGuard.c
> +++ b/MdeModulePkg/Core/PiSmmCore/HeapGuard.c
> @@ -553,7 +553,7 @@ UnsetGuardPage (
>                                           mSmmMemoryAttribute,
>                                           BaseAddress,
>                                           EFI_PAGE_SIZE,
> -                                         EFI_MEMORY_RP
> +                                         EFI_MEMORY_RP|EFI_MEMORY_RO|EFI_MEMORY_XP
>                                           );
>      ASSERT_EFI_ERROR (Status);
>      mOnGuarding = FALSE;
> --
> 2.31.1.windows.1
>
>
>
> 
>
>