Re: [PATCH v2 2/2] mkimage: arm64-efi: Align first section to page

[Daniel Kiper]

On Sun, Dec 23, 2018 at 03:52:07AM +0100, Alexander Graf wrote:
> In order to enforce NX semantics on non-code pages, UEFI firmware
> may require that all code is EFI_PAGE_SIZE (4k) aligned. A similar
> change has recently been applied to edk2 to accomodate for the same
> fact:
>
>   https://lists.01.org/pipermail/edk2-devel/2018-December/033708.html
>
> This patch adapts grub to also implement the same alignment guarantees
> and thus ensures we can boot even when strict permission checks are in
> place.
>
> Signed-off-by: Alexander Graf <address@hidden>
>
> ---
>
> v1 -> v2:
>
>   - Mention only NX requirement in patch description
>   - Use GRUB_EFI_PAGE_SIZE
> ---
>  util/mkimage.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/util/mkimage.c b/util/mkimage.c
> index 88b991764..de93c5a13 100644
> --- a/util/mkimage.c
> +++ b/util/mkimage.c
> @@ -39,6 +39,7 @@
>  #include <string.h>
>  #include <stdlib.h>
>  #include <assert.h>
> +#include <grub/efi/memory.h>
>  #include <grub/efi/pe32.h>
>  #include <grub/uboot/image.h>
>  #include <grub/arm/reloc.h>
> @@ -623,7 +624,7 @@ static const struct grub_install_image_target_desc 
> image_targets[] =
>        .decompressor_uncompressed_size = TARGET_NO_FIELD,
>        .decompressor_uncompressed_addr = TARGET_NO_FIELD,
>        .section_align = GRUB_PE32_SECTION_ALIGNMENT,
> -      .vaddr_offset = EFI64_HEADER_SIZE,
> +      .vaddr_offset = GRUB_EFI_PAGE_SIZE,

Nack.

I think that we will soon have the same problem on other targtes.
So, I would try this:

#define EFI32_HEADER_SIZE ALIGN_UP (GRUB_PE32_MSDOS_STUB_SIZE           \
                                    + GRUB_PE32_SIGNATURE_SIZE          \
                                    + sizeof (struct grub_pe32_coff_header) \
                                    + sizeof (struct grub_pe32_optional_header) 
\
                                    + 4 * sizeof (struct 
grub_pe32_section_table), \
                                    ALIGN_UP (GRUB_PE32_SECTION_ALIGNMENT, 
GRUB_EFI_PAGE_SIZE))

#define EFI64_HEADER_SIZE ALIGN_UP (GRUB_PE32_MSDOS_STUB_SIZE           \
                                    + GRUB_PE32_SIGNATURE_SIZE          \
                                    + sizeof (struct grub_pe32_coff_header) \
                                    + sizeof (struct grub_pe64_optional_header) 
\
                                    + 4 * sizeof (struct 
grub_pe32_section_table), \
                                    ALIGN_UP (GRUB_PE32_SECTION_ALIGNMENT, 
GRUB_EFI_PAGE_SIZE))

And there is another problem with your proposal. What will happen
if EFI64_HEADER_SIZE > GRUB_EFI_PAGE_SIZE?

Additionally, why arm-efi is different?

Daniel