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powerpc/mkimage: Fix CHRP note descsz

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Currently, an image generated with 'grub-mkimage -n' causes an error when
read with 'readelf -a':

Displaying notes found at file offset 0x000106f0 with length 0x0000002c:
  Owner                Data size        Description
readelf: Warning: note with invalid namesz and/or descsz found at offset 0x0
readelf: Warning:  type: 0x1275, namesize: 0x00000008, descsize: 0x0000002c, alignment: 4

This is because the descsz of the CHRP note is set to
 sizeof (struct grub_ieee1275_note)
which is the size of the entire note, including name and elf header. The
desczs should contain only the contents, not the name and header sizes.

Set the descsz instead to 'sizeof (struct grub_ieee1275_note_desc)'

Resultant readelf output:

Displaying notes found at file offset 0x00010710 with length 0x0000002c:
  Owner                Data size        Description
  PowerPC              0x00000018       Unknown note type: (0x00001275)
   description data: ff ff ff ff 00 c0 00 00 ff ff ff ff ff ff ff ff ff ff ff ff 00 00 40 00

So far as I can tell this issue has existed for as long as the note
generation code has existed, but I guess nothing really checks descsz.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
This commit is contained in:
Daniel Axtens 2020-04-07 16:17:26 +10:00 committed by Daniel Kiper
parent 2a6308b954
commit 06fd69a3fd
1 changed files with 1 additions and 1 deletions
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2
util/grub-mkimagexx.c
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@ -463,7 +463,7 @@ SUFFIX (grub_mkimage_generate_elf) (const struct grub_install_image_target_desc
grub_util_info ("adding CHRP NOTE segment");
note_ptr->header.n_namesz = grub_host_to_target32 (sizeof (GRUB_IEEE1275_NOTE_NAME));
note_ptr->header.n_descsz = grub_host_to_target32 (note_size);
note_ptr->header.n_descsz = grub_host_to_target32 (sizeof (struct grub_ieee1275_note_desc));
note_ptr->header.n_type = grub_host_to_target32 (GRUB_IEEE1275_NOTE_TYPE);
strcpy (note_ptr->name, GRUB_IEEE1275_NOTE_NAME);
note_ptr->descriptor.real_mode = grub_host_to_target32 (0xffffffff);