The patch below does not apply to the 5.11-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 02c587733c8161355a43e6e110c2e29bd0acff72 Mon Sep 17 00:00:00 2001 From: Walter Wu <walter-zh.wu@xxxxxxxxxxxx> Date: Fri, 16 Apr 2021 15:46:00 -0700 Subject: [PATCH] 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. This patch fixes the following compilation warning: include/linux/kasan.h:333:30: warning: 'CONFIG_KASAN_STACK' is not defined, evaluates to 0 [-Wundef] [akpm@xxxxxxxxxxxxxxxxxxxx: fix merge snafu] Link: https://bugzilla.kernel.org/show_bug.cgi?id=210221 [1] Link: https://lkml.kernel.org/r/20210226012531.29231-1-walter-zh.wu@xxxxxxxxxxxx Fixes: d9b571c885a8 ("kasan: fix KASAN_STACK dependency for HW_TAGS") 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 <ryabinin.a.a@xxxxxxxxx> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Cc: Alexander Potapenko <glider@xxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> diff --git a/arch/arm64/kernel/sleep.S b/arch/arm64/kernel/sleep.S index 5bfd9b87f85d..4ea9392f86e0 100644 --- a/arch/arm64/kernel/sleep.S +++ b/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 diff --git a/arch/x86/kernel/acpi/wakeup_64.S b/arch/x86/kernel/acpi/wakeup_64.S index 56b6865afb2a..d5d8a352eafa 100644 --- a/arch/x86/kernel/acpi/wakeup_64.S +++ b/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. diff --git a/include/linux/kasan.h b/include/linux/kasan.h index b91732bd05d7..14f72ec96492 100644 --- a/include/linux/kasan.h +++ b/include/linux/kasan.h @@ -330,7 +330,7 @@ static inline bool kasan_check_byte(const void *address) #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) {} diff --git a/lib/Kconfig.kasan b/lib/Kconfig.kasan index fba9909e31b7..cffc2ebbf185 100644 --- a/lib/Kconfig.kasan +++ b/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 @@ -154,12 +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 - depends on KASAN_GENERIC || KASAN_SW_TAGS - 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 diff --git a/mm/kasan/common.c b/mm/kasan/common.c index b5e08d4cefec..7b53291dafa1 100644 --- a/mm/kasan/common.c +++ b/mm/kasan/common.c @@ -63,7 +63,7 @@ void __kasan_unpoison_range(const void *address, size_t size) 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) { diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h index 8c55634d6edd..3436c6bf7c0c 100644 --- a/mm/kasan/kasan.h +++ b/mm/kasan/kasan.h @@ -231,7 +231,7 @@ void *kasan_find_first_bad_addr(void *addr, size_t size); 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) { } diff --git a/mm/kasan/report_generic.c b/mm/kasan/report_generic.c index 41f374585144..de732bc341c5 100644 --- a/mm/kasan/report_generic.c +++ b/mm/kasan/report_generic.c @@ -128,7 +128,7 @@ void kasan_metadata_fetch_row(char *buffer, void *row) 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) diff --git a/scripts/Makefile.kasan b/scripts/Makefile.kasan index 127012f45166..3d791908ed36 100644 --- a/scripts/Makefile.kasan +++ b/scripts/Makefile.kasan @@ -4,6 +4,12 @@ KASAN_SHADOW_OFFSET ?= $(CONFIG_KASAN_SHADOW_OFFSET) cc-param = $(call cc-option, -mllvm -$(1), $(call cc-option, --param $(1))) +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 \ - $(call cc-param,hwasan-instrument-stack=$(CONFIG_KASAN_STACK)) \ + $(call cc-param,hwasan-instrument-stack=$(stack_enable)) \ $(call cc-param,hwasan-use-short-granules=0) \ $(instrumentation_flags) diff --git a/security/Kconfig.hardening b/security/Kconfig.hardening index 269967c4fc1b..a56c36470cb1 100644 --- a/security/Kconfig.hardening +++ b/security/Kconfig.hardening @@ -64,7 +64,7 @@ choice config GCC_PLUGIN_STRUCTLEAK_BYREF bool "zero-init structs passed by reference (strong)" depends on GCC_PLUGINS - depends on !(KASAN && KASAN_STACK=1) + depends on !(KASAN && KASAN_STACK) select GCC_PLUGIN_STRUCTLEAK help Zero-initialize any structures on the stack that may @@ -82,7 +82,7 @@ choice config GCC_PLUGIN_STRUCTLEAK_BYREF_ALL bool "zero-init anything passed by reference (very strong)" depends on GCC_PLUGINS - depends on !(KASAN && KASAN_STACK=1) + depends on !(KASAN && KASAN_STACK) select GCC_PLUGIN_STRUCTLEAK help Zero-initialize any stack variables that may be passed
