scripts/Makefile.kasan

   1 # SPDX-License-Identifier: GPL-2.0
   2 CFLAGS_KASAN_NOSANITIZE := -fno-builtin
   3 KASAN_SHADOW_OFFSET ?= $(CONFIG_KASAN_SHADOW_OFFSET)
   4
   5 cc-param = $(call cc-option, -mllvm -$(1), $(call cc-option, --param $(1)))
   6
   7 ifdef CONFIG_KASAN_STACK
   8         stack_enable := 1
   9 else
  10         stack_enable := 0
  11 endif
  12
  13 ifdef CONFIG_KASAN_GENERIC
  14
  15 ifdef CONFIG_KASAN_INLINE
  16         call_threshold := 10000
  17 else
  18         call_threshold := 0
  19 endif
  20
  21 CFLAGS_KASAN_MINIMAL := -fsanitize=kernel-address
  22
  23 # -fasan-shadow-offset fails without -fsanitize
  24 CFLAGS_KASAN_SHADOW := $(call cc-option, -fsanitize=kernel-address \
  25                         -fasan-shadow-offset=$(KASAN_SHADOW_OFFSET), \
  26                         $(call cc-option, -fsanitize=kernel-address \
  27                         -mllvm -asan-mapping-offset=$(KASAN_SHADOW_OFFSET)))
  28
  29 ifeq ($(strip $(CFLAGS_KASAN_SHADOW)),)
  30         CFLAGS_KASAN := $(CFLAGS_KASAN_MINIMAL)
  31 else
  32         # Now add all the compiler specific options that are valid standalone
  33         CFLAGS_KASAN := $(CFLAGS_KASAN_SHADOW) \
  34          $(call cc-param,asan-globals=1) \
  35          $(call cc-param,asan-instrumentation-with-call-threshold=$(call_threshold)) \
  36          $(call cc-param,asan-stack=$(stack_enable)) \
  37          $(call cc-param,asan-instrument-allocas=1)
  38 endif
  39
  40 endif # CONFIG_KASAN_GENERIC
  41
  42 ifdef CONFIG_KASAN_SW_TAGS
  43
  44 ifdef CONFIG_KASAN_INLINE
  45     instrumentation_flags := $(call cc-param,hwasan-mapping-offset=$(KASAN_SHADOW_OFFSET))
  46 else
  47     instrumentation_flags := $(call cc-param,hwasan-instrument-with-calls=1)
  48 endif
  49
  50 CFLAGS_KASAN := -fsanitize=kernel-hwaddress \
  51                 $(call cc-param,hwasan-instrument-stack=$(stack_enable)) \
  52                 $(call cc-param,hwasan-use-short-granules=0) \
  53                 $(instrumentation_flags)
  54
  55 endif # CONFIG_KASAN_SW_TAGS
  56
  57 export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE