From afe62624c313b78778d4bb4962f5141ac5a0b728 Mon Sep 17 00:00:00 2001
From: Sandrine Bailleux <sandrine.bailleux@arm.com>
Date: Thu, 2 Apr 2020 15:52:44 +0200
Subject: [PATCH] Check for out-of-bound accesses in the platform io policies

The platform io policies array is now always accessed through a fconf getter.
This gives us an ideal spot to check for out-of-bound accesses.

Remove the assertion in plat_get_image_source(), which is now redundant.

Change-Id: Iefe808d530229073b68cbd164d927b8b6662a217
Signed-off-by: Sandrine Bailleux <sandrine.bailleux@arm.com>
---
 include/plat/arm/common/arm_fconf_getter.h | 7 ++++++-
 plat/arm/common/arm_io_storage.c           | 4 ----
 2 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/include/plat/arm/common/arm_fconf_getter.h b/include/plat/arm/common/arm_fconf_getter.h
index 28913a43f..8fd8c7ada 100644
--- a/include/plat/arm/common/arm_fconf_getter.h
+++ b/include/plat/arm/common/arm_fconf_getter.h
@@ -7,10 +7,15 @@
 #ifndef ARM_FCONF_GETTER
 #define ARM_FCONF_GETTER
 
+#include <assert.h>
+
 #include <lib/fconf/fconf.h>
 
 /* ARM io policies */
-#define arm__io_policies_getter(id)	&policies[id]
+#define arm__io_policies_getter(id) __extension__ ({	\
+	assert((id) < MAX_NUMBER_IDS);			\
+	&policies[id];					\
+})
 
 struct plat_io_policy {
 	uintptr_t *dev_handle;
diff --git a/plat/arm/common/arm_io_storage.c b/plat/arm/common/arm_io_storage.c
index 6fcfbd6fb..34b4101e1 100644
--- a/plat/arm/common/arm_io_storage.c
+++ b/plat/arm/common/arm_io_storage.c
@@ -4,8 +4,6 @@
  * SPDX-License-Identifier: BSD-3-Clause
  */
 
-#include <assert.h>
-
 #include <common/debug.h>
 #include <drivers/io/io_driver.h>
 #include <drivers/io/io_fip.h>
@@ -116,8 +114,6 @@ int plat_get_image_source(unsigned int image_id, uintptr_t *dev_handle,
 	int result;
 	const struct plat_io_policy *policy;
 
-	assert(image_id < MAX_NUMBER_IDS);
-
 	policy = FCONF_GET_PROPERTY(arm, io_policies, image_id);
 	result = policy->check(policy->image_spec);
 	if (result == 0) {
-- 
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