[U-Boot] [PATCH v2] Prevent a buffer overflow in mkimage when signing with SHA256

[Michael van der Westhuizen]

Due to the FIT_MAX_HASH_LEN constant not having been updated
to support SHA256 signatures one will always see a buffer
overflow in fit_image_process_hash when signing images that
use this larger hash.  This is exposed by vboot_test.sh.

Signed-off-by: Michael van der Westhuizen <michael at smart-africa.com>
---
Changes in v2:
 * Use the HASH_MAX_DIGEST_SIZE constant from hash.h for the
   FIT_MAX_HASH_LEN.
 * Hide use of struct lmb behind USE_HOSTCC being undefined.

include/image.h | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/include/image.h b/include/image.h
index 1886168..cbbdf26 100644
--- a/include/image.h
+++ b/include/image.h
@@ -45,6 +45,8 @@ struct lmb;
#endif /* USE_HOSTCC */

#if defined(CONFIG_FIT)
+#include <command.h>
+#include <hash.h>
#include <libfdt.h>
#include <fdt_support.h>
# ifdef CONFIG_SPL_BUILD
@@ -328,7 +330,7 @@ typedef struct bootm_headers {
#define BOOTM_STATE_OS_GO (0x00000400)
 int state;

-#ifdef CONFIG_LMB
+#if defined(CONFIG_LMB) && !defined(USE_HOSTCC)
 struct lmb lmb; /* for memory mgmt */
#endif
} bootm_headers_t;
@@ -703,7 +705,7 @@ int bootz_setup(ulong image, ulong *start, ulong *end);
#define FIT_FDT_PROP "fdt"
#define FIT_DEFAULT_PROP "default"

-#define FIT_MAX_HASH_LEN 20 /* max(crc32_len(4), sha1_len(20)) */
+#define FIT_MAX_HASH_LEN HASH_MAX_DIGEST_SIZE

/* cmdline argument format parsing */
int fit_parse_conf(const char *spec, ulong addr_curr,
-- 
2.0.0.rc4