[PATCH 5.11 113/122] kasan: fix hwasan build for gcc

From: Greg Kroah-Hartman
Date: Mon Apr 19 2021 - 09:16:43 EST


From: Arnd Bergmann <arnd@xxxxxxxx>

[ Upstream commit 5c595ac4c776c44b5c59de22ab43b3fe256d9fbb ]

gcc-11 adds support for -fsanitize=kernel-hwaddress, so it becomes
possible to enable CONFIG_KASAN_SW_TAGS.

Unfortunately this fails to build at the moment, because the
corresponding command line arguments use llvm specific syntax.

Change it to use the cc-param macro instead, which works on both clang
and gcc.

[elver@xxxxxxxxxx: fixup for "kasan: fix hwasan build for gcc"]
Link: https://lkml.kernel.org/r/YHQZVfVVLE/LDK2v@xxxxxxxxxxxxxxxx

Link: https://lkml.kernel.org/r/20210323124112.1229772-1-arnd@xxxxxxxxxx
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
Signed-off-by: Marco Elver <elver@xxxxxxxxxx>
Reviewed-by: Marco Elver <elver@xxxxxxxxxx>
Acked-by: Andrey Konovalov <andreyknvl@xxxxxxxxx>
Cc: Masahiro Yamada <masahiroy@xxxxxxxxxx>
Cc: Michal Marek <michal.lkml@xxxxxxxxxxx>
Cc: Andrey Ryabinin <ryabinin.a.a@xxxxxxxxx>
Cc: Nathan Chancellor <nathan@xxxxxxxxxx>
Cc: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Cc: Alexander Potapenko <glider@xxxxxxxxxx>
Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
scripts/Makefile.kasan | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/scripts/Makefile.kasan b/scripts/Makefile.kasan
index 1e000cc2e7b4..127012f45166 100644
--- a/scripts/Makefile.kasan
+++ b/scripts/Makefile.kasan
@@ -2,6 +2,8 @@
CFLAGS_KASAN_NOSANITIZE := -fno-builtin
KASAN_SHADOW_OFFSET ?= $(CONFIG_KASAN_SHADOW_OFFSET)

+cc-param = $(call cc-option, -mllvm -$(1), $(call cc-option, --param $(1)))
+
ifdef CONFIG_KASAN_GENERIC

ifdef CONFIG_KASAN_INLINE
@@ -12,8 +14,6 @@ endif

CFLAGS_KASAN_MINIMAL := -fsanitize=kernel-address

-cc-param = $(call cc-option, -mllvm -$(1), $(call cc-option, --param $(1)))
-
# -fasan-shadow-offset fails without -fsanitize
CFLAGS_KASAN_SHADOW := $(call cc-option, -fsanitize=kernel-address \
-fasan-shadow-offset=$(KASAN_SHADOW_OFFSET), \
@@ -36,14 +36,14 @@ endif # CONFIG_KASAN_GENERIC
ifdef CONFIG_KASAN_SW_TAGS

ifdef CONFIG_KASAN_INLINE
- instrumentation_flags := -mllvm -hwasan-mapping-offset=$(KASAN_SHADOW_OFFSET)
+ instrumentation_flags := $(call cc-param,hwasan-mapping-offset=$(KASAN_SHADOW_OFFSET))
else
- instrumentation_flags := -mllvm -hwasan-instrument-with-calls=1
+ instrumentation_flags := $(call cc-param,hwasan-instrument-with-calls=1)
endif

CFLAGS_KASAN := -fsanitize=kernel-hwaddress \
- -mllvm -hwasan-instrument-stack=$(CONFIG_KASAN_STACK) \
- -mllvm -hwasan-use-short-granules=0 \
+ $(call cc-param,hwasan-instrument-stack=$(CONFIG_KASAN_STACK)) \
+ $(call cc-param,hwasan-use-short-granules=0) \
$(instrumentation_flags)

endif # CONFIG_KASAN_SW_TAGS
--
2.30.2