From: Walter Wu <walter-zh.wu@xxxxxxxxxxxx> Subject: kasan: remove redundant config option CONFIG_KASAN_STACK and CONFIG_KASAN_STACK_ENABLE both enable KASAN stack instrumentation, but we should only need one config, so that we remove CONFIG_KASAN_STACK_ENABLE and make CONFIG_KASAN_STACK workable. see [1]. When enable KASAN stack instrumentation, then for gcc we could do no prompt and default value y, and for clang prompt and default value n. [1]: https://bugzilla.kernel.org/show_bug.cgi?id=210221 [walter-zh.wu@xxxxxxxxxxxx: fix remaining the pre-processor syntax] Link: https://lkml.kernel.org/r/20210108040940.1138-1-walter-zh.wu@xxxxxxxxxxxx Link: https://lkml.kernel.org/r/20210107075315.3482-1-walter-zh.wu@xxxxxxxxxxxx Signed-off-by: Walter Wu <walter-zh.wu@xxxxxxxxxxxx> Suggested-by: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Reviewed-by: Nathan Chancellor <natechancellor@xxxxxxxxx> Acked-by: Arnd Bergmann <arnd@xxxxxxxx> Reviewed-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Cc: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Cc: Alexander Potapenko <glider@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/arm64/kernel/sleep.S | 2 +- arch/x86/kernel/acpi/wakeup_64.S | 2 +- include/linux/kasan.h | 2 +- lib/Kconfig.kasan | 8 ++------ mm/kasan/common.c | 2 +- mm/kasan/kasan.h | 2 +- mm/kasan/report_generic.c | 2 +- scripts/Makefile.kasan | 10 ++++++++-- 8 files changed, 16 insertions(+), 14 deletions(-) --- a/arch/arm64/kernel/sleep.S~kasan-remove-redundant-config-option +++ a/arch/arm64/kernel/sleep.S @@ -134,7 +134,7 @@ SYM_FUNC_START(_cpu_resume) */ bl cpu_do_resume -#if defined(CONFIG_KASAN) && CONFIG_KASAN_STACK +#if defined(CONFIG_KASAN) && defined(CONFIG_KASAN_STACK) mov x0, sp bl kasan_unpoison_task_stack_below #endif --- a/arch/x86/kernel/acpi/wakeup_64.S~kasan-remove-redundant-config-option +++ a/arch/x86/kernel/acpi/wakeup_64.S @@ -115,7 +115,7 @@ SYM_FUNC_START(do_suspend_lowlevel) movq pt_regs_r14(%rax), %r14 movq pt_regs_r15(%rax), %r15 -#if defined(CONFIG_KASAN) && CONFIG_KASAN_STACK +#if defined(CONFIG_KASAN) && defined(CONFIG_KASAN_STACK) /* * The suspend path may have poisoned some areas deeper in the stack, * which we now need to unpoison. --- a/include/linux/kasan.h~kasan-remove-redundant-config-option +++ a/include/linux/kasan.h @@ -321,7 +321,7 @@ static inline bool kasan_check_byte(cons #endif /* CONFIG_KASAN */ -#if defined(CONFIG_KASAN) && CONFIG_KASAN_STACK +#if defined(CONFIG_KASAN) && defined(CONFIG_KASAN_STACK) void kasan_unpoison_task_stack(struct task_struct *task); #else static inline void kasan_unpoison_task_stack(struct task_struct *task) {} --- a/lib/Kconfig.kasan~kasan-remove-redundant-config-option +++ a/lib/Kconfig.kasan @@ -138,9 +138,10 @@ config KASAN_INLINE endchoice -config KASAN_STACK_ENABLE +config KASAN_STACK bool "Enable stack instrumentation (unsafe)" if CC_IS_CLANG && !COMPILE_TEST depends on KASAN_GENERIC || KASAN_SW_TAGS + default y if CC_IS_GCC help The LLVM stack address sanitizer has a know problem that causes excessive stack usage in a lot of functions, see @@ -154,11 +155,6 @@ config KASAN_STACK_ENABLE CONFIG_COMPILE_TEST. On gcc it is assumed to always be safe to use and enabled by default. -config KASAN_STACK - int - default 1 if KASAN_STACK_ENABLE || CC_IS_GCC - default 0 - config KASAN_SW_TAGS_IDENTIFY bool "Enable memory corruption identification" depends on KASAN_SW_TAGS --- a/mm/kasan/common.c~kasan-remove-redundant-config-option +++ a/mm/kasan/common.c @@ -63,7 +63,7 @@ void __kasan_unpoison_range(const void * kasan_unpoison(address, size); } -#if CONFIG_KASAN_STACK +#ifdef CONFIG_KASAN_STACK /* Unpoison the entire stack for a task. */ void kasan_unpoison_task_stack(struct task_struct *task) { --- a/mm/kasan/kasan.h~kasan-remove-redundant-config-option +++ a/mm/kasan/kasan.h @@ -230,7 +230,7 @@ void *kasan_find_first_bad_addr(void *ad const char *kasan_get_bug_type(struct kasan_access_info *info); void kasan_metadata_fetch_row(char *buffer, void *row); -#if defined(CONFIG_KASAN_GENERIC) && CONFIG_KASAN_STACK +#if defined(CONFIG_KASAN_GENERIC) && defined(CONFIG_KASAN_STACK) void kasan_print_address_stack_frame(const void *addr); #else static inline void kasan_print_address_stack_frame(const void *addr) { } --- a/mm/kasan/report_generic.c~kasan-remove-redundant-config-option +++ a/mm/kasan/report_generic.c @@ -128,7 +128,7 @@ void kasan_metadata_fetch_row(char *buff memcpy(buffer, kasan_mem_to_shadow(row), META_BYTES_PER_ROW); } -#if CONFIG_KASAN_STACK +#ifdef CONFIG_KASAN_STACK static bool __must_check tokenize_frame_descr(const char **frame_descr, char *token, size_t max_tok_len, unsigned long *value) --- a/scripts/Makefile.kasan~kasan-remove-redundant-config-option +++ a/scripts/Makefile.kasan @@ -2,6 +2,12 @@ CFLAGS_KASAN_NOSANITIZE := -fno-builtin KASAN_SHADOW_OFFSET ?= $(CONFIG_KASAN_SHADOW_OFFSET) +ifdef CONFIG_KASAN_STACK + stack_enable := 1 +else + stack_enable := 0 +endif + ifdef CONFIG_KASAN_GENERIC ifdef CONFIG_KASAN_INLINE @@ -27,7 +33,7 @@ else CFLAGS_KASAN := $(CFLAGS_KASAN_SHADOW) \ $(call cc-param,asan-globals=1) \ $(call cc-param,asan-instrumentation-with-call-threshold=$(call_threshold)) \ - $(call cc-param,asan-stack=$(CONFIG_KASAN_STACK)) \ + $(call cc-param,asan-stack=$(stack_enable)) \ $(call cc-param,asan-instrument-allocas=1) endif @@ -42,7 +48,7 @@ else endif CFLAGS_KASAN := -fsanitize=kernel-hwaddress \ - -mllvm -hwasan-instrument-stack=$(CONFIG_KASAN_STACK) \ + -mllvm -hwasan-instrument-stack=$(stack_enable) \ -mllvm -hwasan-use-short-granules=0 \ $(instrumentation_flags) _
