1# SPDX-License-Identifier: GPL-2.0
2
3ifdef CONFIG_CC_HAS_KASAN_MEMINTRINSIC_PREFIX
4# Safe for compiler to generate meminstrinsic calls in uninstrumented files.
5CFLAGS_KASAN_NOSANITIZE :=
6else
7# Don't let compiler generate memintrinsic calls in uninstrumented files
8# because they are instrumented.
9CFLAGS_KASAN_NOSANITIZE := -fno-builtin
10endif
11
12KASAN_SHADOW_OFFSET ?= $(CONFIG_KASAN_SHADOW_OFFSET)
13
14cc-param = $(call cc-option, -mllvm -$(1), $(call cc-option, --param $(1)))
15
16ifdef CONFIG_KASAN_STACK
17	stack_enable := 1
18else
19	stack_enable := 0
20endif
21
22ifdef CONFIG_KASAN_GENERIC
23
24ifdef CONFIG_KASAN_INLINE
25	call_threshold := 10000
26else
27	call_threshold := 0
28endif
29
30CFLAGS_KASAN_MINIMAL := -fsanitize=kernel-address
31
32# -fasan-shadow-offset fails without -fsanitize
33CFLAGS_KASAN_SHADOW := $(call cc-option, -fsanitize=kernel-address \
34			-fasan-shadow-offset=$(KASAN_SHADOW_OFFSET), \
35			$(call cc-option, -fsanitize=kernel-address \
36			-mllvm -asan-mapping-offset=$(KASAN_SHADOW_OFFSET)))
37
38ifeq ($(strip $(CFLAGS_KASAN_SHADOW)),)
39	CFLAGS_KASAN := $(CFLAGS_KASAN_MINIMAL)
40else
41	# Now add all the compiler specific options that are valid standalone
42	CFLAGS_KASAN := $(CFLAGS_KASAN_SHADOW) \
43	 $(call cc-param,asan-globals=1) \
44	 $(call cc-param,asan-instrumentation-with-call-threshold=$(call_threshold)) \
45	 $(call cc-param,asan-instrument-allocas=1)
46endif
47
48CFLAGS_KASAN += $(call cc-param,asan-stack=$(stack_enable))
49
50# Instrument memcpy/memset/memmove calls by using instrumented __asan_mem*()
51# instead. With compilers that don't support this option, compiler-inserted
52# memintrinsics won't be checked by KASAN on GENERIC_ENTRY architectures.
53CFLAGS_KASAN += $(call cc-param,asan-kernel-mem-intrinsic-prefix=1)
54
55endif # CONFIG_KASAN_GENERIC
56
57ifdef CONFIG_KASAN_SW_TAGS
58
59ifdef CONFIG_KASAN_INLINE
60    instrumentation_flags := $(call cc-param,hwasan-mapping-offset=$(KASAN_SHADOW_OFFSET))
61else
62    instrumentation_flags := $(call cc-param,hwasan-instrument-with-calls=1)
63endif
64
65CFLAGS_KASAN := -fsanitize=kernel-hwaddress \
66		$(call cc-param,hwasan-instrument-stack=$(stack_enable)) \
67		$(call cc-param,hwasan-use-short-granules=0) \
68		$(call cc-param,hwasan-inline-all-checks=0) \
69		$(instrumentation_flags)
70
71# Instrument memcpy/memset/memmove calls by using instrumented __hwasan_mem*().
72ifeq ($(call clang-min-version, 150000)$(call gcc-min-version, 130000),y)
73CFLAGS_KASAN += $(call cc-param,hwasan-kernel-mem-intrinsic-prefix=1)
74endif
75
76endif # CONFIG_KASAN_SW_TAGS
77
78export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE
79