scripts/Makefile.kasan

   1 # SPDX-License-Identifier: GPL-2.0
   2
   3 ifdef CONFIG_CC_HAS_KASAN_MEMINTRINSIC_PREFIX
   4 # Safe for compiler to generate meminstrinsic calls in uninstrumented files.
   5 CFLAGS_KASAN_NOSANITIZE :=
   6 else
   7 # Don't let compiler generate memintrinsic calls in uninstrumented files
   8 # because they are instrumented.
   9 CFLAGS_KASAN_NOSANITIZE := -fno-builtin
  10 endif
  11
  12 KASAN_SHADOW_OFFSET ?= $(CONFIG_KASAN_SHADOW_OFFSET)
  13
  14 cc-param = $(call cc-option, -mllvm -$(1), $(call cc-option, --param $(1)))
  15
  16 ifdef CONFIG_KASAN_STACK
  17         stack_enable := 1
  18 else
  19         stack_enable := 0
  20 endif
  21
  22 ifdef CONFIG_KASAN_GENERIC
  23
  24 ifdef CONFIG_KASAN_INLINE
  25         call_threshold := 10000
  26 else
  27         call_threshold := 0
  28 endif
  29
  30 CFLAGS_KASAN_MINIMAL := -fsanitize=kernel-address
  31
  32 # -fasan-shadow-offset fails without -fsanitize
  33 CFLAGS_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
  38 ifeq ($(strip $(CFLAGS_KASAN_SHADOW)),)
  39         CFLAGS_KASAN := $(CFLAGS_KASAN_MINIMAL)
  40 else
  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)
  46 endif
  47
  48 CFLAGS_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.
  53 CFLAGS_KASAN += $(call cc-param,asan-kernel-mem-intrinsic-prefix=1)
  54
  55 endif # CONFIG_KASAN_GENERIC
  56
  57 ifdef CONFIG_KASAN_SW_TAGS
  58
  59 ifdef CONFIG_KASAN_INLINE
  60     instrumentation_flags := $(call cc-param,hwasan-mapping-offset=$(KASAN_SHADOW_OFFSET))
  61 else
  62     instrumentation_flags := $(call cc-param,hwasan-instrument-with-calls=1)
  63 endif
  64
  65 CFLAGS_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                 $(instrumentation_flags)
  70
  71 # Instrument memcpy/memset/memmove calls by using instrumented __hwasan_mem*().
  72 ifeq ($(call clang-min-version, 150000)$(call gcc-min-version, 130000),y)
  73 CFLAGS_KASAN += $(call cc-param,hwasan-kernel-mem-intrinsic-prefix=1)
  74 endif
  75
  76 endif # CONFIG_KASAN_SW_TAGS
  77
  78 export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE