From: Mark Rutland mark.rutland@arm.com
[ Upstream commit 34b5560db40d2941cfbe82eca1641353d5aed1a9 ]
The generic Makefile.kasan propagates CONFIG_KASAN_SHADOW_OFFSET into KASAN_SHADOW_OFFSET, but only does so for CONFIG_KASAN_GENERIC.
Since commit:
6bd1d0be0e97936d ("arm64: kasan: Switch to using KASAN_SHADOW_OFFSET")
... arm64 defines CONFIG_KASAN_SHADOW_OFFSET in Kconfig rather than defining KASAN_SHADOW_OFFSET in a Makefile. Thus, if CONFIG_KASAN_SW_TAGS && KASAN_INLINE are selected, we get build time splats due to KASAN_SHADOW_OFFSET not being set:
| [mark@lakrids:~/src/linux]% usellvm 8.0.1 usekorg 8.1.0 make ARCH=arm64 CROSS_COMPILE=aarch64-linux- CC=clang | scripts/kconfig/conf --syncconfig Kconfig | CC scripts/mod/empty.o | clang (LLVM option parsing): for the -hwasan-mapping-offset option: '' value invalid for uint argument! | scripts/Makefile.build:273: recipe for target 'scripts/mod/empty.o' failed | make[1]: *** [scripts/mod/empty.o] Error 1 | Makefile:1123: recipe for target 'prepare0' failed | make: *** [prepare0] Error 2
Let's fix this by always propagating CONFIG_KASAN_SHADOW_OFFSET into KASAN_SHADOW_OFFSET if CONFIG_KASAN is selected, moving the existing common definition of +CFLAGS_KASAN_NOSANITIZE to the top of Makefile.kasan.
Cc: Catalin Marinas catalin.marinas@arm.com Signed-off-by: Mark Rutland mark.rutland@arm.com Acked-by: Andrey Ryabinin aryabinin@virtuozzo.com Tested-by Steve Capper steve.capper@arm.com Signed-off-by: Will Deacon will@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- scripts/Makefile.kasan | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-)
diff --git a/scripts/Makefile.kasan b/scripts/Makefile.kasan index 6410bd22fe387..03757cc60e06c 100644 --- a/scripts/Makefile.kasan +++ b/scripts/Makefile.kasan @@ -1,4 +1,9 @@ # SPDX-License-Identifier: GPL-2.0 +ifdef CONFIG_KASAN +CFLAGS_KASAN_NOSANITIZE := -fno-builtin +KASAN_SHADOW_OFFSET ?= $(CONFIG_KASAN_SHADOW_OFFSET) +endif + ifdef CONFIG_KASAN_GENERIC
ifdef CONFIG_KASAN_INLINE @@ -7,8 +12,6 @@ else call_threshold := 0 endif
-KASAN_SHADOW_OFFSET ?= $(CONFIG_KASAN_SHADOW_OFFSET) - CFLAGS_KASAN_MINIMAL := -fsanitize=kernel-address
cc-param = $(call cc-option, -mllvm -$(1), $(call cc-option, --param $(1))) @@ -45,7 +48,3 @@ CFLAGS_KASAN := -fsanitize=kernel-hwaddress \ $(instrumentation_flags)
endif # CONFIG_KASAN_SW_TAGS - -ifdef CONFIG_KASAN -CFLAGS_KASAN_NOSANITIZE := -fno-builtin -endif