From: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Subject: kasan: rename (un)poison_shadow to (un)poison_range This is a preparatory commit for the upcoming addition of a new hardware tag-based (MTE-based) KASAN mode. The new mode won't be using shadow memory. Rename external annotation kasan_unpoison_shadow() to kasan_unpoison_range(), and introduce internal functions (un)poison_range() (without kasan_ prefix). Co-developed-by: Marco Elver <elver@xxxxxxxxxx> Link: https://lkml.kernel.org/r/fccdcaa13dc6b2211bf363d6c6d499279a54fe3a.1606161801.git.andreyknvl@xxxxxxxxxx Signed-off-by: Marco Elver <elver@xxxxxxxxxx> Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@xxxxxxx> Reviewed-by: Alexander Potapenko <glider@xxxxxxxxxx> Tested-by: Vincenzo Frascino <vincenzo.frascino@xxxxxxx> Cc: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx> Cc: Branislav Rankov <Branislav.Rankov@xxxxxxx> Cc: Catalin Marinas <catalin.marinas@xxxxxxx> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Cc: Evgenii Stepanov <eugenis@xxxxxxxxxx> Cc: Kevin Brodsky <kevin.brodsky@xxxxxxx> Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx> Cc: Will Deacon <will.deacon@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/kasan.h | 6 ++-- kernel/fork.c | 4 +-- mm/kasan/common.c | 49 ++++++++++++++++++++++------------------ mm/kasan/generic.c | 23 ++++++++---------- mm/kasan/kasan.h | 3 +- mm/kasan/tags.c | 2 - mm/slab_common.c | 2 - 7 files changed, 47 insertions(+), 42 deletions(-) --- a/include/linux/kasan.h~kasan-rename-unpoison_shadow-to-unpoison_range +++ a/include/linux/kasan.h @@ -72,7 +72,7 @@ extern void kasan_enable_current(void); /* Disable reporting bugs for current task */ extern void kasan_disable_current(void); -void kasan_unpoison_shadow(const void *address, size_t size); +void kasan_unpoison_range(const void *address, size_t size); void kasan_unpoison_task_stack(struct task_struct *task); @@ -109,7 +109,7 @@ struct kasan_cache { size_t __ksize(const void *); static inline void kasan_unpoison_slab(const void *ptr) { - kasan_unpoison_shadow(ptr, __ksize(ptr)); + kasan_unpoison_range(ptr, __ksize(ptr)); } size_t kasan_metadata_size(struct kmem_cache *cache); @@ -118,7 +118,7 @@ void kasan_restore_multi_shot(bool enabl #else /* CONFIG_KASAN */ -static inline void kasan_unpoison_shadow(const void *address, size_t size) {} +static inline void kasan_unpoison_range(const void *address, size_t size) {} static inline void kasan_unpoison_task_stack(struct task_struct *task) {} --- a/kernel/fork.c~kasan-rename-unpoison_shadow-to-unpoison_range +++ a/kernel/fork.c @@ -225,8 +225,8 @@ static unsigned long *alloc_thread_stack if (!s) continue; - /* Clear the KASAN shadow of the stack. */ - kasan_unpoison_shadow(s->addr, THREAD_SIZE); + /* Mark stack accessible for KASAN. */ + kasan_unpoison_range(s->addr, THREAD_SIZE); /* Clear stale pointers from reused stack. */ memset(s->addr, 0, THREAD_SIZE); --- a/mm/kasan/common.c~kasan-rename-unpoison_shadow-to-unpoison_range +++ a/mm/kasan/common.c @@ -108,7 +108,7 @@ void *memcpy(void *dest, const void *src * Poisons the shadow memory for 'size' bytes starting from 'addr'. * Memory addresses should be aligned to KASAN_SHADOW_SCALE_SIZE. */ -void kasan_poison_shadow(const void *address, size_t size, u8 value) +void poison_range(const void *address, size_t size, u8 value) { void *shadow_start, *shadow_end; @@ -125,7 +125,7 @@ void kasan_poison_shadow(const void *add __memset(shadow_start, value, shadow_end - shadow_start); } -void kasan_unpoison_shadow(const void *address, size_t size) +void unpoison_range(const void *address, size_t size) { u8 tag = get_tag(address); @@ -136,7 +136,7 @@ void kasan_unpoison_shadow(const void *a */ address = reset_tag(address); - kasan_poison_shadow(address, size, tag); + poison_range(address, size, tag); if (size & KASAN_SHADOW_MASK) { u8 *shadow = (u8 *)kasan_mem_to_shadow(address + size); @@ -148,12 +148,17 @@ void kasan_unpoison_shadow(const void *a } } +void kasan_unpoison_range(const void *address, size_t size) +{ + unpoison_range(address, size); +} + static void __kasan_unpoison_stack(struct task_struct *task, const void *sp) { void *base = task_stack_page(task); size_t size = sp - base; - kasan_unpoison_shadow(base, size); + unpoison_range(base, size); } /* Unpoison the entire stack for a task. */ @@ -172,7 +177,7 @@ asmlinkage void kasan_unpoison_task_stac */ void *base = (void *)((unsigned long)watermark & ~(THREAD_SIZE - 1)); - kasan_unpoison_shadow(base, watermark - base); + unpoison_range(base, watermark - base); } void kasan_alloc_pages(struct page *page, unsigned int order) @@ -186,13 +191,13 @@ void kasan_alloc_pages(struct page *page tag = random_tag(); for (i = 0; i < (1 << order); i++) page_kasan_tag_set(page + i, tag); - kasan_unpoison_shadow(page_address(page), PAGE_SIZE << order); + unpoison_range(page_address(page), PAGE_SIZE << order); } void kasan_free_pages(struct page *page, unsigned int order) { if (likely(!PageHighMem(page))) - kasan_poison_shadow(page_address(page), + poison_range(page_address(page), PAGE_SIZE << order, KASAN_FREE_PAGE); } @@ -284,18 +289,18 @@ void kasan_poison_slab(struct page *page for (i = 0; i < compound_nr(page); i++) page_kasan_tag_reset(page + i); - kasan_poison_shadow(page_address(page), page_size(page), - KASAN_KMALLOC_REDZONE); + poison_range(page_address(page), page_size(page), + KASAN_KMALLOC_REDZONE); } void kasan_unpoison_object_data(struct kmem_cache *cache, void *object) { - kasan_unpoison_shadow(object, cache->object_size); + unpoison_range(object, cache->object_size); } void kasan_poison_object_data(struct kmem_cache *cache, void *object) { - kasan_poison_shadow(object, + poison_range(object, round_up(cache->object_size, KASAN_SHADOW_SCALE_SIZE), KASAN_KMALLOC_REDZONE); } @@ -408,7 +413,7 @@ static bool __kasan_slab_free(struct kme } rounded_up_size = round_up(cache->object_size, KASAN_SHADOW_SCALE_SIZE); - kasan_poison_shadow(object, rounded_up_size, KASAN_KMALLOC_FREE); + poison_range(object, rounded_up_size, KASAN_KMALLOC_FREE); if ((IS_ENABLED(CONFIG_KASAN_GENERIC) && !quarantine) || unlikely(!(cache->flags & SLAB_KASAN))) @@ -448,9 +453,9 @@ static void *__kasan_kmalloc(struct kmem tag = assign_tag(cache, object, false, keep_tag); /* Tag is ignored in set_tag without CONFIG_KASAN_SW_TAGS */ - kasan_unpoison_shadow(set_tag(object, tag), size); - kasan_poison_shadow((void *)redzone_start, redzone_end - redzone_start, - KASAN_KMALLOC_REDZONE); + unpoison_range(set_tag(object, tag), size); + poison_range((void *)redzone_start, redzone_end - redzone_start, + KASAN_KMALLOC_REDZONE); if (cache->flags & SLAB_KASAN) kasan_set_track(&get_alloc_info(cache, object)->alloc_track, flags); @@ -489,9 +494,9 @@ void * __must_check kasan_kmalloc_large( KASAN_SHADOW_SCALE_SIZE); redzone_end = (unsigned long)ptr + page_size(page); - kasan_unpoison_shadow(ptr, size); - kasan_poison_shadow((void *)redzone_start, redzone_end - redzone_start, - KASAN_PAGE_REDZONE); + unpoison_range(ptr, size); + poison_range((void *)redzone_start, redzone_end - redzone_start, + KASAN_PAGE_REDZONE); return (void *)ptr; } @@ -523,7 +528,7 @@ void kasan_poison_kfree(void *ptr, unsig kasan_report_invalid_free(ptr, ip); return; } - kasan_poison_shadow(ptr, page_size(page), KASAN_FREE_PAGE); + poison_range(ptr, page_size(page), KASAN_FREE_PAGE); } else { __kasan_slab_free(page->slab_cache, ptr, ip, false); } @@ -709,7 +714,7 @@ int kasan_populate_vmalloc(unsigned long * // vmalloc() allocates memory * // let a = area->addr * // we reach kasan_populate_vmalloc - * // and call kasan_unpoison_shadow: + * // and call unpoison_range: * STORE shadow(a), unpoison_val * ... * STORE shadow(a+99), unpoison_val x = LOAD p @@ -744,7 +749,7 @@ void kasan_poison_vmalloc(const void *st return; size = round_up(size, KASAN_SHADOW_SCALE_SIZE); - kasan_poison_shadow(start, size, KASAN_VMALLOC_INVALID); + poison_range(start, size, KASAN_VMALLOC_INVALID); } void kasan_unpoison_vmalloc(const void *start, unsigned long size) @@ -752,7 +757,7 @@ void kasan_unpoison_vmalloc(const void * if (!is_vmalloc_or_module_addr(start)) return; - kasan_unpoison_shadow(start, size); + unpoison_range(start, size); } static int kasan_depopulate_vmalloc_pte(pte_t *ptep, unsigned long addr, --- a/mm/kasan/generic.c~kasan-rename-unpoison_shadow-to-unpoison_range +++ a/mm/kasan/generic.c @@ -202,11 +202,11 @@ static void register_global(struct kasan { size_t aligned_size = round_up(global->size, KASAN_SHADOW_SCALE_SIZE); - kasan_unpoison_shadow(global->beg, global->size); + unpoison_range(global->beg, global->size); - kasan_poison_shadow(global->beg + aligned_size, - global->size_with_redzone - aligned_size, - KASAN_GLOBAL_REDZONE); + poison_range(global->beg + aligned_size, + global->size_with_redzone - aligned_size, + KASAN_GLOBAL_REDZONE); } void __asan_register_globals(struct kasan_global *globals, size_t size) @@ -285,13 +285,12 @@ void __asan_alloca_poison(unsigned long WARN_ON(!IS_ALIGNED(addr, KASAN_ALLOCA_REDZONE_SIZE)); - kasan_unpoison_shadow((const void *)(addr + rounded_down_size), - size - rounded_down_size); - kasan_poison_shadow(left_redzone, KASAN_ALLOCA_REDZONE_SIZE, - KASAN_ALLOCA_LEFT); - kasan_poison_shadow(right_redzone, - padding_size + KASAN_ALLOCA_REDZONE_SIZE, - KASAN_ALLOCA_RIGHT); + unpoison_range((const void *)(addr + rounded_down_size), + size - rounded_down_size); + poison_range(left_redzone, KASAN_ALLOCA_REDZONE_SIZE, + KASAN_ALLOCA_LEFT); + poison_range(right_redzone, padding_size + KASAN_ALLOCA_REDZONE_SIZE, + KASAN_ALLOCA_RIGHT); } EXPORT_SYMBOL(__asan_alloca_poison); @@ -301,7 +300,7 @@ void __asan_allocas_unpoison(const void if (unlikely(!stack_top || stack_top > stack_bottom)) return; - kasan_unpoison_shadow(stack_top, stack_bottom - stack_top); + unpoison_range(stack_top, stack_bottom - stack_top); } EXPORT_SYMBOL(__asan_allocas_unpoison); --- a/mm/kasan/kasan.h~kasan-rename-unpoison_shadow-to-unpoison_range +++ a/mm/kasan/kasan.h @@ -150,7 +150,8 @@ static inline bool addr_has_shadow(const return (addr >= kasan_shadow_to_mem((void *)KASAN_SHADOW_START)); } -void kasan_poison_shadow(const void *address, size_t size, u8 value); +void poison_range(const void *address, size_t size, u8 value); +void unpoison_range(const void *address, size_t size); /** * check_memory_region - Check memory region, and report if invalid access. --- a/mm/kasan/tags.c~kasan-rename-unpoison_shadow-to-unpoison_range +++ a/mm/kasan/tags.c @@ -153,7 +153,7 @@ EXPORT_SYMBOL(__hwasan_storeN_noabort); void __hwasan_tag_memory(unsigned long addr, u8 tag, unsigned long size) { - kasan_poison_shadow((void *)addr, size, tag); + poison_range((void *)addr, size, tag); } EXPORT_SYMBOL(__hwasan_tag_memory); --- a/mm/slab_common.c~kasan-rename-unpoison_shadow-to-unpoison_range +++ a/mm/slab_common.c @@ -1176,7 +1176,7 @@ size_t ksize(const void *objp) * We assume that ksize callers could use whole allocated area, * so we need to unpoison this area. */ - kasan_unpoison_shadow(objp, size); + kasan_unpoison_range(objp, size); return size; } EXPORT_SYMBOL(ksize); _
