[PATCH v2] efi_loader: Fix memory corruption on 32bit systems

[Dan Carpenter]

The issue is this line:

	new_efi = efi_prepare_aligned_image(efi, (u64 *)&efi_size);

The efi_size variable is type size_t and on a 32 bit system that's 32
bits.  The u64 type is obviously 64 bits.  So we write 8 bytes to a 4
byte buffer which corrupts memory.

Fix this by changing the type of efi_prepare_aligned_image() to a
size_t pointer.

Signed-off-by: Dan Carpenter <dan.carpenter at linaro.org>
---
v2: Change efi_prepare_aligned_image() instead of changing
efi_image_authenticate().  This is a cleaner way to fix the problem.

 include/efi_loader.h              | 2 +-
 lib/efi_loader/efi_image_loader.c | 4 ++--
 lib/efi_loader/efi_tcg2.c         | 2 +-
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/include/efi_loader.h b/include/efi_loader.h
index b5fa0fe01ded..9c1a9ed16af6 100644
--- a/include/efi_loader.h
+++ b/include/efi_loader.h
@@ -1022,7 +1022,7 @@ bool efi_secure_boot_enabled(void);
 
 bool efi_capsule_auth_enabled(void);
 
-void *efi_prepare_aligned_image(void *efi, u64 *efi_size);
+void *efi_prepare_aligned_image(void *efi, size_t *efi_size);
 
 bool efi_image_parse(void *efi, size_t len, struct efi_image_regions **regp,
 		     WIN_CERTIFICATE **auth, size_t *auth_len);
diff --git a/lib/efi_loader/efi_image_loader.c b/lib/efi_loader/efi_image_loader.c
index 26df0da16c93..64980008403b 100644
--- a/lib/efi_loader/efi_image_loader.c
+++ b/lib/efi_loader/efi_image_loader.c
@@ -313,7 +313,7 @@ static int cmp_pe_section(const void *arg1, const void *arg2)
  *
  * Return:	valid pointer to a image, return NULL if allocation fails.
  */
-void *efi_prepare_aligned_image(void *efi, u64 *efi_size)
+void *efi_prepare_aligned_image(void *efi, size_t *efi_size)
 {
 	size_t new_efi_size;
 	void *new_efi;
@@ -600,7 +600,7 @@ static bool efi_image_authenticate(void *efi, size_t efi_size)
 	if (!efi_secure_boot_enabled())
 		return true;
 
-	new_efi = efi_prepare_aligned_image(efi, (u64 *)&efi_size);
+	new_efi = efi_prepare_aligned_image(efi, &efi_size);
 	if (!new_efi)
 		return false;
 
diff --git a/lib/efi_loader/efi_tcg2.c b/lib/efi_loader/efi_tcg2.c
index 49f8a5e77cbf..d57afd0c498b 100644
--- a/lib/efi_loader/efi_tcg2.c
+++ b/lib/efi_loader/efi_tcg2.c
@@ -882,7 +882,7 @@ out:
  *
  * Return:	status code
  */
-static efi_status_t tcg2_hash_pe_image(void *efi, u64 efi_size,
+static efi_status_t tcg2_hash_pe_image(void *efi, size_t efi_size,
 				       struct tpml_digest_values *digest_list)
 {
 	WIN_CERTIFICATE *wincerts = NULL;
-- 
2.39.2