[PATCH v2 6/6] LoongArch: Add ARCH_HAS_FORTIFY_SOURCE

[Qing Zhang]

FORTIFY_SOURCE could detect various overflows at compile and run time.
ARCH_HAS_FORTIFY_SOURCE means that the architecture can be built and
run with CONFIG_FORTIFY_SOURCE. Select it in LoongArch.

See more about this feature from commit 6974f0c4555e
("include/linux/string.h: add the option of fortified string.h functions").

Signed-off-by: Qing Zhang <zhangqing@xxxxxxxxxxx>
---
 arch/loongarch/Kconfig              | 1 +
 arch/loongarch/include/asm/string.h | 4 ++++
 2 files changed, 5 insertions(+)

diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
index 61f883c51045..6c525e50bb7c 100644
--- a/arch/loongarch/Kconfig
+++ b/arch/loongarch/Kconfig
@@ -11,6 +11,7 @@ config LOONGARCH
 	select ARCH_ENABLE_MEMORY_HOTPLUG
 	select ARCH_ENABLE_MEMORY_HOTREMOVE
 	select ARCH_HAS_ACPI_TABLE_UPGRADE	if ACPI
+	select ARCH_HAS_FORTIFY_SOURCE
 	select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS
 	select ARCH_HAS_PTE_SPECIAL
 	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
diff --git a/arch/loongarch/include/asm/string.h b/arch/loongarch/include/asm/string.h
index a6482abdc8b3..5bb5a90d2681 100644
--- a/arch/loongarch/include/asm/string.h
+++ b/arch/loongarch/include/asm/string.h
@@ -28,6 +28,10 @@ extern void *__memmove(void *__dest, __const__ void *__src, size_t __n);
 #define memcpy(dst, src, len) __memcpy(dst, src, len)
 #define memmove(dst, src, len) __memmove(dst, src, len)
 
+#ifndef __NO_FORTIFY
+#define __NO_FORTIFY /* FORTIFY_SOURCE uses __builtin_memcpy, etc. */
+#endif
+
 #endif
 
 #endif /* _ASM_STRING_H */
-- 
2.20.1