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| author | Matt Fleming <matt.fleming@intel.com> | 2013-05-09 14:24:21 +0100 |
|---|---|---|
| committer | Matt Fleming <matt.fleming@intel.com> | 2013-05-13 12:08:07 +0100 |
| commit | 5de984d3f42258fb49cfb713002a2e2aae4b16a4 (patch) | |
| tree | bbe519a2a9c846954d46330cf2c44e0435a9af0c | |
| parent | fe283b78c973268f2d1f0309826ceeb5c9e8978d (diff) | |
| download | syslinux-5de984d3f42258fb49cfb713002a2e2aae4b16a4.tar.gz syslinux-5de984d3f42258fb49cfb713002a2e2aae4b16a4.tar.xz syslinux-5de984d3f42258fb49cfb713002a2e2aae4b16a4.zip | |
efi: Fill out MS-DOS header relocs field
The relocs field in the MS-DOS header actually indicates the size of the
MS-DOS header and needs filling out with a value >= 0x40. See,
http://www.ctyme.com/intr/rb-2939.htm#table1594 -
"18h WORD offset within header of relocation table
40h or greater for new-format (NE,LE,LX,W3,PE,etc.)
executable"
Incidentally, file(1) checks the value of that field to differentiate
MS-DOS executables from PE-COFF files, e.g.
file(1) output before:
MS-DOS executable
file(1) output after:
PE32+ executable (EFI application) x86-64 (stripped to external PDB), for MS Windows
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
| -rw-r--r-- | efi/wrapper.c | 8 | ||||
| -rw-r--r-- | efi/wrapper.h | 4 |
2 files changed, 11 insertions, 1 deletions
diff --git a/efi/wrapper.c b/efi/wrapper.c index 0943534c..1b1d5d33 100644 --- a/efi/wrapper.c +++ b/efi/wrapper.c @@ -60,6 +60,14 @@ static void write_header(FILE *f, __uint32_t entry, __uint32_t so_size, __uint8_ memset(&hdr, 0, sizeof(hdr)); hdr.msdos_signature = MSDOS_SIGNATURE; + + /* + * The relocs table pointer needs to be >= 0x40 for PE files. It + * informs things like file(1) that we are not an MS-DOS + * executable. + */ + hdr.relocs_ptr = 0x40; + hdr.pe_hdr = OFFSETOF(struct header, pe_signature); hdr.pe_signature = PE_SIGNATURE; fwrite(&hdr, sizeof(hdr), 1, f); diff --git a/efi/wrapper.h b/efi/wrapper.h index 492c262b..4f769914 100644 --- a/efi/wrapper.h +++ b/efi/wrapper.h @@ -28,7 +28,9 @@ struct header { __uint16_t msdos_signature; - __uint8_t _pad1[0x3c - 2]; + __uint8_t _pad1[0x16]; + __uint16_t relocs_ptr; + __uint8_t __pad2[0x3c - 0x1a]; __uint32_t pe_hdr; __uint16_t pe_signature; __uint16_t _pad2; |