Check for out-of-bound accesses in the CoT description
The chain of trust array is now always accessed through a fconf getter.
This gives us an ideal spot to check for out-of-bound accesses.
Change-Id: Ic5ea20e43cf8ca959bb7f9b60de7c0839b390add
Signed-off-by: Sandrine Bailleux <sandrine.bailleux@arm.com>
diff --git a/include/drivers/auth/auth_mod.h b/include/drivers/auth/auth_mod.h
index 6c48124..1dc9ff4 100644
--- a/include/drivers/auth/auth_mod.h
+++ b/include/drivers/auth/auth_mod.h
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2015-2019, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2020, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
@@ -14,6 +14,8 @@
#include <drivers/auth/auth_common.h>
#include <drivers/auth/img_parser_mod.h>
+#include <lib/utils_def.h>
+
/*
* Image flags
*/
@@ -41,9 +43,11 @@
/* Macro to register a CoT defined as an array of auth_img_desc_t pointers */
#define REGISTER_COT(_cot) \
const auth_img_desc_t *const *const cot_desc_ptr = (_cot); \
+ const size_t cot_desc_size = ARRAY_SIZE(_cot); \
unsigned int auth_img_flags[MAX_NUMBER_IDS]
extern const auth_img_desc_t *const *const cot_desc_ptr;
+extern const size_t cot_desc_size;
extern unsigned int auth_img_flags[MAX_NUMBER_IDS];
#endif /* TRUSTED_BOARD_BOOT */
diff --git a/include/lib/fconf/fconf_tbbr_getter.h b/include/lib/fconf/fconf_tbbr_getter.h
index eddc0c4..db98b68 100644
--- a/include/lib/fconf/fconf_tbbr_getter.h
+++ b/include/lib/fconf/fconf_tbbr_getter.h
@@ -7,10 +7,15 @@
#ifndef FCONF_TBBR_GETTER_H
#define FCONF_TBBR_GETTER_H
+#include <assert.h>
+
#include <lib/fconf/fconf.h>
/* TBBR related getter */
-#define tbbr__cot_getter(id) cot_desc_ptr[id]
+#define tbbr__cot_getter(id) __extension__ ({ \
+ assert((id) < cot_desc_size); \
+ cot_desc_ptr[id]; \
+})
#define tbbr__dyn_config_getter(id) tbbr_dyn_config.id