Merge "corstone700: adding support for stack protector for the FVP" into integration

plat/arm/board/corstone700/corstone700_stack_protector.c

+/*
+ * Copyright (c) 2020, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <stdint.h>
+
+#include <arch_helpers.h>
+#include <plat/common/platform.h>
+
+static uint32_t plat_generate_random_number(void)
+{
+	uintptr_t return_addr = (uintptr_t)__builtin_return_address(0U);
+	uintptr_t frame_addr = (uintptr_t)__builtin_frame_address(0U);
+	uint64_t cntpct = read_cntpct_el0();
+
+	/* Generate 32-bit pattern: saving the 2 least significant bytes
+	 * in random_lo and random_hi
+	 */
+	uint16_t random_lo = (uint16_t)(
+			(((uint64_t)return_addr) << 13) ^ frame_addr ^ cntpct
+			);
+
+	uint16_t random_hi = (uint16_t)(
+			(((uint64_t)frame_addr) << 15) ^ return_addr ^ cntpct
+			);
+
+	return (((uint32_t)random_hi) << 16) | random_lo;
+}
+
+u_register_t plat_get_stack_protector_canary(void)
+{
+	return  plat_generate_random_number(); /* a 32-bit pattern is returned */
+}

plat/arm/board/corstone700/sp_min/sp_min-corstone700.mk

 #
-# Copyright (c) 2019, Arm Limited and Contributors. All rights reserved.
+# Copyright (c) 2019-2020, Arm Limited and Contributors. All rights reserved.
 #
 # SPDX-License-Identifier: BSD-3-Clause
 #
@@ -15,4 +15,10 @@ BL32_SOURCES	+=	drivers/cfi/v2m/v2m_flash.c				\
 			plat/arm/board/corstone700/sp_min/corstone700_sp_min_setup.c	\
 			${CORSTONE700_GIC_SOURCES}
 
+ifneq (${ENABLE_STACK_PROTECTOR},0)
+	ifneq (${ENABLE_STACK_PROTECTOR},none)
+		BL32_SOURCES += plat/arm/board/corstone700/corstone700_stack_protector.c
+	endif
+endif
+
 include plat/arm/common/sp_min/arm_sp_min.mk