x86/efi: Fix boot failure with EFI stub

commit 54b52d872680 ("x86/efi: Build our own EFI services pointer
table") introduced a regression because the 64-bit file_size()
implementation passed a pointer to a 32-bit data object, instead of a
pointer to a 64-bit object.

Because the firmware treats the object as 64-bits regardless it was
reading random values from the stack for the upper 32-bits.

This resulted in people being unable to boot their machines, after
seeing the following error messages,

    Failed to get file info size
    Failed to alloc highmem for files

Reported-by: Dzmitry Sledneu <dzmitry.sledneu@gmail.com>
Reported-by: Koen Kooi <koen@dominion.thruhere.net>
Tested-by: Koen Kooi <koen@dominion.thruhere.net>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>

diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c
index 1e61461..2801655 100644 (file)
--- a/arch/x86/boot/compressed/eboot.c
+++ b/arch/x86/boot/compressed/eboot.c
@@ -112,7 +112,7 @@ __file_size64(void *__fh, efi_char16_t *filename_16,
        efi_file_info_t *info;
        efi_status_t status;
        efi_guid_t info_guid = EFI_FILE_INFO_ID;
-       u32 info_sz;
+       u64 info_sz;
 
        status = efi_early->call((unsigned long)fh->open, fh, &h, filename_16,
                                 EFI_FILE_MODE_READ, (u64)0);