[RFC PATCH] util/mkimage: Fix wrong PE32+ section sizes for some arches

[Javier Martinez Canillas]

Commit f60ba9e5945 (util/mkimage: Refactor section setup to use a helper)
added a helper function to setup PE sections. But it also changed how the
raw data offsets were calculated since all the section sizes are aligned.

But for some platforms (i.e: ia64 and aa64) the kernel image size wasn't
aligned using the section alignment, which causes the PE section headers
to not match the actual section sizes in the PE32+ binary file.

This caused problems on ia64 EFI machines, since the .data section size
is bigger than the actual section in the PE32+ binary, overlapping with
part of the mods section. That leads to GRUB not being able to load any
built-in module.

Fix it by aligning the kernel_size to the section alignment, that makes
the sizes and offsets in the PE section headers to match the sections
in the PE32+ binary file.

Reported-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
---

Hello, this is an RFC because I want someone else more familiar with this
to double check that this approach is sane.

It would be also useful if someone can test on an aarch64 machine, I have
compared the generated EFI binaries and are the same in both cases. But
still it seems to me that an explicit alignment is needed for EM_AARCH64.

Best regards,
Javier

 util/grub-mkimagexx.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/util/grub-mkimagexx.c b/util/grub-mkimagexx.c
index 00f49ccaaaf..2d0c9a0cb6b 100644
--- a/util/grub-mkimagexx.c
+++ b/util/grub-mkimagexx.c
@@ -2375,6 +2375,10 @@ SUFFIX (grub_mkimage_load_image) (const char 
*kernel_path,
 
          layout->got_off = layout->kernel_size;
          layout->kernel_size += ALIGN_UP (layout->got_size, 16);
+
+          if (image_target->id == IMAGE_EFI)
+            layout->kernel_size = ALIGN_UP (layout->kernel_size,
+                                            image_target->section_align);
        }
       if (image_target->elf_target == EM_AARCH64)
        {
@@ -2386,6 +2390,11 @@ SUFFIX (grub_mkimage_load_image) (const char 
*kernel_path,
 
          layout->got_off = layout->kernel_size;
          layout->kernel_size += ALIGN_UP (layout->got_size, 16);
+
+
+          if (image_target->id == IMAGE_EFI)
+            layout->kernel_size = ALIGN_UP (layout->kernel_size,
+                                            image_target->section_align);
        }
 #endif
     }
-- 
2.31.1