/* SPDX-License-Identifier: GPL-2.0 */ #ifndef __MM_KASAN_KASAN_H #define __MM_KASAN_KASAN_H #include #include #include #include #if IS_ENABLED(CONFIG_KUNIT) /* Used in KUnit-compatible KASAN tests. */ struct kunit_kasan_status { bool report_found; bool sync_fault; }; #endif #ifdef CONFIG_KASAN_HW_TAGS #include #include "../slab.h" DECLARE_STATIC_KEY_TRUE(kasan_flag_vmalloc); DECLARE_STATIC_KEY_TRUE(kasan_flag_stacktrace); enum kasan_mode { KASAN_MODE_SYNC, KASAN_MODE_ASYNC, KASAN_MODE_ASYMM, }; extern enum kasan_mode kasan_mode __ro_after_init; static inline bool kasan_vmalloc_enabled(void) { return static_branch_likely(&kasan_flag_vmalloc); } static inline bool kasan_stack_collection_enabled(void) { return static_branch_unlikely(&kasan_flag_stacktrace); } static inline bool kasan_async_fault_possible(void) { return kasan_mode == KASAN_MODE_ASYNC || kasan_mode == KASAN_MODE_ASYMM; } static inline bool kasan_sync_fault_possible(void) { return kasan_mode == KASAN_MODE_SYNC || kasan_mode == KASAN_MODE_ASYMM; } #else static inline bool kasan_stack_collection_enabled(void) { return true; } static inline bool kasan_async_fault_possible(void) { return false; } static inline bool kasan_sync_fault_possible(void) { return true; } #endif #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) #define KASAN_GRANULE_SIZE (1UL << KASAN_SHADOW_SCALE_SHIFT) #else #include #define KASAN_GRANULE_SIZE MTE_GRANULE_SIZE #endif #define KASAN_GRANULE_MASK (KASAN_GRANULE_SIZE - 1) #define KASAN_MEMORY_PER_SHADOW_PAGE (KASAN_GRANULE_SIZE << PAGE_SHIFT) #ifdef CONFIG_KASAN_GENERIC #define KASAN_FREE_PAGE 0xFF /* page was freed */ #define KASAN_PAGE_REDZONE 0xFE /* redzone for kmalloc_large allocations */ #define KASAN_KMALLOC_REDZONE 0xFC /* redzone inside slub object */ #define KASAN_KMALLOC_FREE 0xFB /* object was freed (kmem_cache_free/kfree) */ #define KASAN_VMALLOC_INVALID 0xF8 /* unallocated space in vmapped page */ #else #define KASAN_FREE_PAGE KASAN_TAG_INVALID #define KASAN_PAGE_REDZONE KASAN_TAG_INVALID #define KASAN_KMALLOC_REDZONE KASAN_TAG_INVALID #define KASAN_KMALLOC_FREE KASAN_TAG_INVALID #define KASAN_VMALLOC_INVALID KASAN_TAG_INVALID /* only for SW_TAGS */ #endif #ifdef CONFIG_KASAN_GENERIC #define KASAN_KMALLOC_FREETRACK 0xFA /* object was freed and has free track set */ #define KASAN_GLOBAL_REDZONE 0xF9 /* redzone for global variable */ /* * Stack redzone shadow values * (Those are compiler's ABI, don't change them) */ #define KASAN_STACK_LEFT 0xF1 #define KASAN_STACK_MID 0xF2 #define KASAN_STACK_RIGHT 0xF3 #define KASAN_STACK_PARTIAL 0xF4 /* * alloca redzone shadow values */ #define KASAN_ALLOCA_LEFT 0xCA #define KASAN_ALLOCA_RIGHT 0xCB #define KASAN_ALLOCA_REDZONE_SIZE 32 /* * Stack frame marker (compiler ABI). */ #define KASAN_CURRENT_STACK_FRAME_MAGIC 0x41B58AB3 /* Don't break randconfig/all*config builds */ #ifndef KASAN_ABI_VERSION #define KASAN_ABI_VERSION 1 #endif #endif /* CONFIG_KASAN_GENERIC */ /* Metadata layout customization. */ #define META_BYTES_PER_BLOCK 1 #define META_BLOCKS_PER_ROW 16 #define META_BYTES_PER_ROW (META_BLOCKS_PER_ROW * META_BYTES_PER_BLOCK) #define META_MEM_BYTES_PER_ROW (META_BYTES_PER_ROW * KASAN_GRANULE_SIZE) #define META_ROWS_AROUND_ADDR 2 struct kasan_access_info { const void *access_addr; const void *first_bad_addr; size_t access_size; bool is_write; unsigned long ip; }; /* The layout of struct dictated by compiler */ struct kasan_source_location { const char *filename; int line_no; int column_no; }; /* The layout of struct dictated by compiler */ struct kasan_global { const void *beg; /* Address of the beginning of the global variable. */ size_t size; /* Size of the global variable. */ size_t size_with_redzone; /* Size of the variable + size of the red zone. 32 bytes aligned */ const void *name; const void *module_name; /* Name of the module where the global variable is declared. */ unsigned long has_dynamic_init; /* This needed for C++ */ #if KASAN_ABI_VERSION >= 4 struct kasan_source_location *location; #endif #if KASAN_ABI_VERSION >= 5 char *odr_indicator; #endif }; /** * Structures to keep alloc and free tracks * */ #define KASAN_STACK_DEPTH 64 struct kasan_track { u32 pid; depot_stack_handle_t stack; }; #if defined(CONFIG_KASAN_TAGS_IDENTIFY) && defined(CONFIG_KASAN_SW_TAGS) #define KASAN_NR_FREE_STACKS 5 #else #define KASAN_NR_FREE_STACKS 1 #endif struct kasan_alloc_meta { struct kasan_track alloc_track; #ifdef CONFIG_KASAN_GENERIC /* * The auxiliary stack is stored into struct kasan_alloc_meta. * The free stack is stored into struct kasan_free_meta. */ depot_stack_handle_t aux_stack[2]; #else struct kasan_track free_track[KASAN_NR_FREE_STACKS]; #endif #ifdef CONFIG_KASAN_TAGS_IDENTIFY u8 free_pointer_tag[KASAN_NR_FREE_STACKS]; u8 free_track_idx; #endif }; struct qlist_node { struct qlist_node *next; }; /* * Generic mode either stores free meta in the object itself or in the redzone * after the object. In the former case free meta offset is 0, in the latter * case it has some sane value smaller than INT_MAX. Use INT_MAX as free meta * offset when free meta isn't present. */ #define KASAN_NO_FREE_META INT_MAX struct kasan_free_meta { #ifdef CONFIG_KASAN_GENERIC /* This field is used while the object is in the quarantine. * Otherwise it might be used for the allocator freelist. */ struct qlist_node quarantine_link; struct kasan_track free_track; #endif }; struct kasan_alloc_meta *kasan_get_alloc_meta(struct kmem_cache *cache, const void *object); #ifdef CONFIG_KASAN_GENERIC struct kasan_free_meta *kasan_get_free_meta(struct kmem_cache *cache, const void *object); #endif #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) static inline const void *kasan_shadow_to_mem(const void *shadow_addr) { return (void *)(((unsigned long)shadow_addr - KASAN_SHADOW_OFFSET) << KASAN_SHADOW_SCALE_SHIFT); } static inline bool addr_has_metadata(const void *addr) { return (addr >= kasan_shadow_to_mem((void *)KASAN_SHADOW_START)); } /** * kasan_check_range - Check memory region, and report if invalid access. * @addr: the accessed address * @size: the accessed size * @write: true if access is a write access * @ret_ip: return address * @return: true if access was valid, false if invalid */ bool kasan_check_range(unsigned long addr, size_t size, bool write, unsigned long ret_ip); #else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */ static inline bool addr_has_metadata(const void *addr) { return (is_vmalloc_addr(addr) || virt_addr_valid(addr)); } #endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */ #if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS) void kasan_print_tags(u8 addr_tag, const void *addr); #else static inline void kasan_print_tags(u8 addr_tag, const void *addr) { } #endif 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) && 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) { } #endif bool kasan_report(unsigned long addr, size_t size, bool is_write, unsigned long ip); void kasan_report_invalid_free(void *object, unsigned long ip); struct page *kasan_addr_to_page(const void *addr); struct slab *kasan_addr_to_slab(const void *addr); depot_stack_handle_t kasan_save_stack(gfp_t flags, bool can_alloc); void kasan_set_track(struct kasan_track *track, gfp_t flags); void kasan_set_free_info(struct kmem_cache *cache, void *object, u8 tag); struct kasan_track *kasan_get_free_track(struct kmem_cache *cache, void *object, u8 tag); #if defined(CONFIG_KASAN_GENERIC) && \ (defined(CONFIG_SLAB) || defined(CONFIG_SLUB)) bool kasan_quarantine_put(struct kmem_cache *cache, void *object); void kasan_quarantine_reduce(void); void kasan_quarantine_remove_cache(struct kmem_cache *cache); #else static inline bool kasan_quarantine_put(struct kmem_cache *cache, void *object) { return false; } static inline void kasan_quarantine_reduce(void) { } static inline void kasan_quarantine_remove_cache(struct kmem_cache *cache) { } #endif #ifndef arch_kasan_set_tag static inline const void *arch_kasan_set_tag(const void *addr, u8 tag) { return addr; } #endif #ifndef arch_kasan_get_tag #define arch_kasan_get_tag(addr) 0 #endif #define set_tag(addr, tag) ((void *)arch_kasan_set_tag((addr), (tag))) #define get_tag(addr) arch_kasan_get_tag(addr) #ifdef CONFIG_KASAN_HW_TAGS #ifndef arch_enable_tagging_sync #define arch_enable_tagging_sync() #endif #ifndef arch_enable_tagging_async #define arch_enable_tagging_async() #endif #ifndef arch_enable_tagging_asymm #define arch_enable_tagging_asymm() #endif #ifndef arch_force_async_tag_fault #define arch_force_async_tag_fault() #endif #ifndef arch_get_random_tag #define arch_get_random_tag() (0xFF) #endif #ifndef arch_get_mem_tag #define arch_get_mem_tag(addr) (0xFF) #endif #ifndef arch_set_mem_tag_range #define arch_set_mem_tag_range(addr, size, tag, init) ((void *)(addr)) #endif #define hw_enable_tagging_sync() arch_enable_tagging_sync() #define hw_enable_tagging_async() arch_enable_tagging_async() #define hw_enable_tagging_asymm() arch_enable_tagging_asymm() #define hw_force_async_tag_fault() arch_force_async_tag_fault() #define hw_get_random_tag() arch_get_random_tag() #define hw_get_mem_tag(addr) arch_get_mem_tag(addr) #define hw_set_mem_tag_range(addr, size, tag, init) \ arch_set_mem_tag_range((addr), (size), (tag), (init)) #else /* CONFIG_KASAN_HW_TAGS */ #define hw_enable_tagging_sync() #define hw_enable_tagging_async() #define hw_enable_tagging_asymm() #endif /* CONFIG_KASAN_HW_TAGS */ #if defined(CONFIG_KASAN_HW_TAGS) && IS_ENABLED(CONFIG_KASAN_KUNIT_TEST) void kasan_enable_tagging(void); void kasan_force_async_fault(void); #else /* CONFIG_KASAN_HW_TAGS || CONFIG_KASAN_KUNIT_TEST */ static inline void kasan_enable_tagging(void) { } static inline void kasan_force_async_fault(void) { } #endif /* CONFIG_KASAN_HW_TAGS || CONFIG_KASAN_KUNIT_TEST */ #ifdef CONFIG_KASAN_SW_TAGS u8 kasan_random_tag(void); #elif defined(CONFIG_KASAN_HW_TAGS) static inline u8 kasan_random_tag(void) { return hw_get_random_tag(); } #else static inline u8 kasan_random_tag(void) { return 0; } #endif #ifdef CONFIG_KASAN_HW_TAGS static inline void kasan_poison(const void *addr, size_t size, u8 value, bool init) { addr = kasan_reset_tag(addr); /* Skip KFENCE memory if called explicitly outside of sl*b. */ if (is_kfence_address(addr)) return; if (WARN_ON((unsigned long)addr & KASAN_GRANULE_MASK)) return; if (WARN_ON(size & KASAN_GRANULE_MASK)) return; hw_set_mem_tag_range((void *)addr, size, value, init); } static inline void kasan_unpoison(const void *addr, size_t size, bool init) { u8 tag = get_tag(addr); addr = kasan_reset_tag(addr); /* Skip KFENCE memory if called explicitly outside of sl*b. */ if (is_kfence_address(addr)) return; if (WARN_ON((unsigned long)addr & KASAN_GRANULE_MASK)) return; /* * Explicitly initialize the memory with the precise object size to * avoid overwriting the SLAB redzone. This disables initialization in * the arch code and may thus lead to performance penalty. The penalty * is accepted since SLAB redzones aren't enabled in production builds. */ if (__slub_debug_enabled() && init && ((unsigned long)size & KASAN_GRANULE_MASK)) { init = false; memzero_explicit((void *)addr, size); } size = round_up(size, KASAN_GRANULE_SIZE); hw_set_mem_tag_range((void *)addr, size, tag, init); } static inline bool kasan_byte_accessible(const void *addr) { u8 ptr_tag = get_tag(addr); u8 mem_tag = hw_get_mem_tag((void *)addr); return ptr_tag == KASAN_TAG_KERNEL || ptr_tag == mem_tag; } #else /* CONFIG_KASAN_HW_TAGS */ /** * kasan_poison - mark the memory range as inaccessible * @addr - range start address, must be aligned to KASAN_GRANULE_SIZE * @size - range size, must be aligned to KASAN_GRANULE_SIZE * @value - value that's written to metadata for the range * @init - whether to initialize the memory range (only for hardware tag-based) * * The size gets aligned to KASAN_GRANULE_SIZE before marking the range. */ void kasan_poison(const void *addr, size_t size, u8 value, bool init); /** * kasan_unpoison - mark the memory range as accessible * @addr - range start address, must be aligned to KASAN_GRANULE_SIZE * @size - range size, can be unaligned * @init - whether to initialize the memory range (only for hardware tag-based) * * For the tag-based modes, the @size gets aligned to KASAN_GRANULE_SIZE before * marking the range. * For the generic mode, the last granule of the memory range gets partially * unpoisoned based on the @size. */ void kasan_unpoison(const void *addr, size_t size, bool init); bool kasan_byte_accessible(const void *addr); #endif /* CONFIG_KASAN_HW_TAGS */ #ifdef CONFIG_KASAN_GENERIC /** * kasan_poison_last_granule - mark the last granule of the memory range as * inaccessible * @addr - range start address, must be aligned to KASAN_GRANULE_SIZE * @size - range size * * This function is only available for the generic mode, as it's the only mode * that has partially poisoned memory granules. */ void kasan_poison_last_granule(const void *address, size_t size); #else /* CONFIG_KASAN_GENERIC */ static inline void kasan_poison_last_granule(const void *address, size_t size) { } #endif /* CONFIG_KASAN_GENERIC */ #ifndef kasan_arch_is_ready static inline bool kasan_arch_is_ready(void) { return true; } #elif !defined(CONFIG_KASAN_GENERIC) || !defined(CONFIG_KASAN_OUTLINE) #error kasan_arch_is_ready only works in KASAN generic outline mode! #endif /* * Exported functions for interfaces called from assembly or from generated * code. Declarations here to avoid warning about missing declarations. */ asmlinkage void kasan_unpoison_task_stack_below(const void *watermark); void __asan_register_globals(struct kasan_global *globals, size_t size); void __asan_unregister_globals(struct kasan_global *globals, size_t size); void __asan_handle_no_return(void); void __asan_alloca_poison(unsigned long addr, size_t size); void __asan_allocas_unpoison(const void *stack_top, const void *stack_bottom); void __asan_load1(unsigned long addr); void __asan_store1(unsigned long addr); void __asan_load2(unsigned long addr); void __asan_store2(unsigned long addr); void __asan_load4(unsigned long addr); void __asan_store4(unsigned long addr); void __asan_load8(unsigned long addr); void __asan_store8(unsigned long addr); void __asan_load16(unsigned long addr); void __asan_store16(unsigned long addr); void __asan_loadN(unsigned long addr, size_t size); void __asan_storeN(unsigned long addr, size_t size); void __asan_load1_noabort(unsigned long addr); void __asan_store1_noabort(unsigned long addr); void __asan_load2_noabort(unsigned long addr); void __asan_store2_noabort(unsigned long addr); void __asan_load4_noabort(unsigned long addr); void __asan_store4_noabort(unsigned long addr); void __asan_load8_noabort(unsigned long addr); void __asan_store8_noabort(unsigned long addr); void __asan_load16_noabort(unsigned long addr); void __asan_store16_noabort(unsigned long addr); void __asan_loadN_noabort(unsigned long addr, size_t size); void __asan_storeN_noabort(unsigned long addr, size_t size); void __asan_report_load1_noabort(unsigned long addr); void __asan_report_store1_noabort(unsigned long addr); void __asan_report_load2_noabort(unsigned long addr); void __asan_report_store2_noabort(unsigned long addr); void __asan_report_load4_noabort(unsigned long addr); void __asan_report_store4_noabort(unsigned long addr); void __asan_report_load8_noabort(unsigned long addr); void __asan_report_store8_noabort(unsigned long addr); void __asan_report_load16_noabort(unsigned long addr); void __asan_report_store16_noabort(unsigned long addr); void __asan_report_load_n_noabort(unsigned long addr, size_t size); void __asan_report_store_n_noabort(unsigned long addr, size_t size); void __asan_set_shadow_00(const void *addr, size_t size); void __asan_set_shadow_f1(const void *addr, size_t size); void __asan_set_shadow_f2(const void *addr, size_t size); void __asan_set_shadow_f3(const void *addr, size_t size); void __asan_set_shadow_f5(const void *addr, size_t size); void __asan_set_shadow_f8(const void *addr, size_t size); void __hwasan_load1_noabort(unsigned long addr); void __hwasan_store1_noabort(unsigned long addr); void __hwasan_load2_noabort(unsigned long addr); void __hwasan_store2_noabort(unsigned long addr); void __hwasan_load4_noabort(unsigned long addr); void __hwasan_store4_noabort(unsigned long addr); void __hwasan_load8_noabort(unsigned long addr); void __hwasan_store8_noabort(unsigned long addr); void __hwasan_load16_noabort(unsigned long addr); void __hwasan_store16_noabort(unsigned long addr); void __hwasan_loadN_noabort(unsigned long addr, size_t size); void __hwasan_storeN_noabort(unsigned long addr, size_t size); void __hwasan_tag_memory(unsigned long addr, u8 tag, unsigned long size); #endif