xref: /openbmc/linux/scripts/Makefile.kasan (revision 79f382b9)
1# SPDX-License-Identifier: GPL-2.0
2CFLAGS_KASAN_NOSANITIZE := -fno-builtin
3KASAN_SHADOW_OFFSET ?= $(CONFIG_KASAN_SHADOW_OFFSET)
4
5ifdef CONFIG_KASAN_GENERIC
6
7ifdef CONFIG_KASAN_INLINE
8	call_threshold := 10000
9else
10	call_threshold := 0
11endif
12
13CFLAGS_KASAN_MINIMAL := -fsanitize=kernel-address
14
15cc-param = $(call cc-option, -mllvm -$(1), $(call cc-option, --param $(1)))
16
17# -fasan-shadow-offset fails without -fsanitize
18CFLAGS_KASAN_SHADOW := $(call cc-option, -fsanitize=kernel-address \
19			-fasan-shadow-offset=$(KASAN_SHADOW_OFFSET), \
20			$(call cc-option, -fsanitize=kernel-address \
21			-mllvm -asan-mapping-offset=$(KASAN_SHADOW_OFFSET)))
22
23ifeq ($(strip $(CFLAGS_KASAN_SHADOW)),)
24	CFLAGS_KASAN := $(CFLAGS_KASAN_MINIMAL)
25else
26	# Now add all the compiler specific options that are valid standalone
27	CFLAGS_KASAN := $(CFLAGS_KASAN_SHADOW) \
28	 $(call cc-param,asan-globals=1) \
29	 $(call cc-param,asan-instrumentation-with-call-threshold=$(call_threshold)) \
30	 $(call cc-param,asan-stack=$(CONFIG_KASAN_STACK)) \
31	 $(call cc-param,asan-instrument-allocas=1)
32endif
33
34endif # CONFIG_KASAN_GENERIC
35
36ifdef CONFIG_KASAN_SW_TAGS
37
38ifdef CONFIG_KASAN_INLINE
39    instrumentation_flags := -mllvm -hwasan-mapping-offset=$(KASAN_SHADOW_OFFSET)
40else
41    instrumentation_flags := -mllvm -hwasan-instrument-with-calls=1
42endif
43
44CFLAGS_KASAN := -fsanitize=kernel-hwaddress \
45		-mllvm -hwasan-instrument-stack=$(CONFIG_KASAN_STACK) \
46		-mllvm -hwasan-use-short-granules=0 \
47		$(instrumentation_flags)
48
49endif # CONFIG_KASAN_SW_TAGS
50
51export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE
52