From 19532869feb9b0a97d17ddc14609d1e53a5b60db Mon Sep 17 00:00:00 2001 From: Nathan Chancellor Date: Fri, 24 Sep 2021 15:44:00 -0700 Subject: [PATCH] kasan: always respect CONFIG_KASAN_STACK Currently, the asan-stack parameter is only passed along if CFLAGS_KASAN_SHADOW is not empty, which requires KASAN_SHADOW_OFFSET to be defined in Kconfig so that the value can be checked. In RISC-V's case, KASAN_SHADOW_OFFSET is not defined in Kconfig, which means that asan-stack does not get disabled with clang even when CONFIG_KASAN_STACK is disabled, resulting in large stack warnings with allmodconfig: drivers/video/fbdev/omap2/omapfb/displays/panel-lgphilips-lb035q02.c:117:12: error: stack frame size (14400) exceeds limit (2048) in function 'lb035q02_connect' [-Werror,-Wframe-larger-than] static int lb035q02_connect(struct omap_dss_device *dssdev) ^ 1 error generated. Ensure that the value of CONFIG_KASAN_STACK is always passed along to the compiler so that these warnings do not happen when CONFIG_KASAN_STACK is disabled. Link: https://github.com/ClangBuiltLinux/linux/issues/1453 References: 6baec880d7a5 ("kasan: turn off asan-stack for clang-8 and earlier") Link: https://lkml.kernel.org/r/20210922205525.570068-1-nathan@kernel.org Signed-off-by: Nathan Chancellor Reviewed-by: Marco Elver Cc: Andrey Ryabinin Cc: Alexander Potapenko Cc: Andrey Konovalov Cc: Dmitry Vyukov Cc: Nick Desaulniers Cc: Arnd Bergmann Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/Makefile.kasan | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/scripts/Makefile.kasan b/scripts/Makefile.kasan index 801c415bac59..b9e94c5e7097 100644 --- a/scripts/Makefile.kasan +++ b/scripts/Makefile.kasan @@ -33,10 +33,11 @@ else CFLAGS_KASAN := $(CFLAGS_KASAN_SHADOW) \ $(call cc-param,asan-globals=1) \ $(call cc-param,asan-instrumentation-with-call-threshold=$(call_threshold)) \ - $(call cc-param,asan-stack=$(stack_enable)) \ $(call cc-param,asan-instrument-allocas=1) endif +CFLAGS_KASAN += $(call cc-param,asan-stack=$(stack_enable)) + endif # CONFIG_KASAN_GENERIC ifdef CONFIG_KASAN_SW_TAGS