While efi_memory_attributes_table_t::entry isn't used directly as an
array, it is used as a base for pointer arithmetic. The type is wrong
as it's not technically an array of efi_memory_desc_t's; they could be
larger. Regardless, leave the type unchanged and remove the old style
"0" array size. Additionally replace the open-coded entry offset code
with the existing efi_memdesc_ptr() helper.
Signed-off-by: Kees Cook <kees@xxxxxxxxxx>
---
Cc: Ard Biesheuvel <ardb@xxxxxxxxxx>
Cc: linux-efi@xxxxxxxxxxxxxxx
---
drivers/firmware/efi/memattr.c | 2 +-
include/linux/efi.h | 6 +++++-
2 files changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/firmware/efi/memattr.c b/drivers/firmware/efi/memattr.c
index ab85bf8e165a..164203429fa7 100644
--- a/drivers/firmware/efi/memattr.c
+++ b/drivers/firmware/efi/memattr.c
@@ -164,7 +164,7 @@ int __init efi_memattr_apply_permissions(struct mm_struct *mm,
bool valid;
char buf[64];
- valid = entry_is_valid((void *)tbl->entry + i * tbl->desc_size,
+ valid = entry_is_valid(efi_memdesc_ptr(tbl->entry, tbl->desc_size, i),
&md);
size = md.num_pages << EFI_PAGE_SHIFT;
if (efi_enabled(EFI_DBG) || !valid)
diff --git a/include/linux/efi.h b/include/linux/efi.h
index fbdfcc9a81e6..40475d77231c 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -607,7 +607,11 @@ typedef struct {
u32 num_entries;
u32 desc_size;
u32 flags;
- efi_memory_desc_t entry[0];
+ /*
+ * There are @num_entries following, each of size @desc_size bytes,
+ * including an efi_memory_desc_t header. See efi_memdesc_ptr().
+ */
+ efi_memory_desc_t entry[];
} efi_memory_attributes_table_t;
typedef struct {
--
2.34.1
