1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __MM_KASAN_KASAN_H
3 #define __MM_KASAN_KASAN_H
5 #include <linux/kasan.h>
6 #include <linux/kasan-tags.h>
7 #include <linux/kfence.h>
8 #include <linux/stackdepot.h>
10 #ifdef CONFIG_KASAN_HW_TAGS
12 #include <linux/static_key.h>
15 DECLARE_STATIC_KEY_TRUE(kasan_flag_vmalloc);
16 DECLARE_STATIC_KEY_TRUE(kasan_flag_stacktrace);
24 extern enum kasan_mode kasan_mode __ro_after_init;
26 static inline bool kasan_vmalloc_enabled(void)
28 return static_branch_likely(&kasan_flag_vmalloc);
31 static inline bool kasan_stack_collection_enabled(void)
33 return static_branch_unlikely(&kasan_flag_stacktrace);
36 static inline bool kasan_async_fault_possible(void)
38 return kasan_mode == KASAN_MODE_ASYNC || kasan_mode == KASAN_MODE_ASYMM;
41 static inline bool kasan_sync_fault_possible(void)
43 return kasan_mode == KASAN_MODE_SYNC || kasan_mode == KASAN_MODE_ASYMM;
48 static inline bool kasan_stack_collection_enabled(void)
53 static inline bool kasan_async_fault_possible(void)
58 static inline bool kasan_sync_fault_possible(void)
65 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
66 #define KASAN_GRANULE_SIZE (1UL << KASAN_SHADOW_SCALE_SHIFT)
68 #include <asm/mte-kasan.h>
69 #define KASAN_GRANULE_SIZE MTE_GRANULE_SIZE
72 #define KASAN_GRANULE_MASK (KASAN_GRANULE_SIZE - 1)
74 #define KASAN_MEMORY_PER_SHADOW_PAGE (KASAN_GRANULE_SIZE << PAGE_SHIFT)
76 #ifdef CONFIG_KASAN_GENERIC
77 #define KASAN_PAGE_FREE 0xFF /* freed page */
78 #define KASAN_PAGE_REDZONE 0xFE /* redzone for kmalloc_large allocation */
79 #define KASAN_SLAB_REDZONE 0xFC /* redzone for slab object */
80 #define KASAN_SLAB_FREE 0xFB /* freed slab object */
81 #define KASAN_VMALLOC_INVALID 0xF8 /* inaccessible space in vmap area */
83 #define KASAN_PAGE_FREE KASAN_TAG_INVALID
84 #define KASAN_PAGE_REDZONE KASAN_TAG_INVALID
85 #define KASAN_SLAB_REDZONE KASAN_TAG_INVALID
86 #define KASAN_SLAB_FREE KASAN_TAG_INVALID
87 #define KASAN_VMALLOC_INVALID KASAN_TAG_INVALID /* only used for SW_TAGS */
90 #ifdef CONFIG_KASAN_GENERIC
92 #define KASAN_SLAB_FREETRACK 0xFA /* freed slab object with free track */
93 #define KASAN_GLOBAL_REDZONE 0xF9 /* redzone for global variable */
95 /* Stack redzone shadow values. Compiler ABI, do not change. */
96 #define KASAN_STACK_LEFT 0xF1
97 #define KASAN_STACK_MID 0xF2
98 #define KASAN_STACK_RIGHT 0xF3
99 #define KASAN_STACK_PARTIAL 0xF4
101 /* alloca redzone shadow values. */
102 #define KASAN_ALLOCA_LEFT 0xCA
103 #define KASAN_ALLOCA_RIGHT 0xCB
105 /* alloca redzone size. Compiler ABI, do not change. */
106 #define KASAN_ALLOCA_REDZONE_SIZE 32
108 /* Stack frame marker. Compiler ABI, do not change. */
109 #define KASAN_CURRENT_STACK_FRAME_MAGIC 0x41B58AB3
111 /* Dummy value to avoid breaking randconfig/all*config builds. */
112 #ifndef KASAN_ABI_VERSION
113 #define KASAN_ABI_VERSION 1
116 #endif /* CONFIG_KASAN_GENERIC */
118 /* Metadata layout customization. */
119 #define META_BYTES_PER_BLOCK 1
120 #define META_BLOCKS_PER_ROW 16
121 #define META_BYTES_PER_ROW (META_BLOCKS_PER_ROW * META_BYTES_PER_BLOCK)
122 #define META_MEM_BYTES_PER_ROW (META_BYTES_PER_ROW * KASAN_GRANULE_SIZE)
123 #define META_ROWS_AROUND_ADDR 2
125 enum kasan_report_type {
127 KASAN_REPORT_INVALID_FREE,
128 KASAN_REPORT_DOUBLE_FREE,
131 struct kasan_report_info {
132 enum kasan_report_type type;
134 void *first_bad_addr;
140 /* Do not change the struct layout: compiler ABI. */
141 struct kasan_source_location {
142 const char *filename;
147 /* Do not change the struct layout: compiler ABI. */
148 struct kasan_global {
149 const void *beg; /* Address of the beginning of the global variable. */
150 size_t size; /* Size of the global variable. */
151 size_t size_with_redzone; /* Size of the variable + size of the redzone. 32 bytes aligned. */
153 const void *module_name; /* Name of the module where the global variable is declared. */
154 unsigned long has_dynamic_init; /* This is needed for C++. */
155 #if KASAN_ABI_VERSION >= 4
156 struct kasan_source_location *location;
158 #if KASAN_ABI_VERSION >= 5
163 /* Structures for keeping alloc and free tracks. */
165 #define KASAN_STACK_DEPTH 64
169 depot_stack_handle_t stack;
172 #if defined(CONFIG_KASAN_TAGS_IDENTIFY) && defined(CONFIG_KASAN_SW_TAGS)
173 #define KASAN_NR_FREE_STACKS 5
175 #define KASAN_NR_FREE_STACKS 1
178 struct kasan_alloc_meta {
179 struct kasan_track alloc_track;
180 /* Generic mode stores free track in kasan_free_meta. */
181 #ifdef CONFIG_KASAN_GENERIC
182 depot_stack_handle_t aux_stack[2];
184 struct kasan_track free_track[KASAN_NR_FREE_STACKS];
186 #ifdef CONFIG_KASAN_TAGS_IDENTIFY
187 u8 free_pointer_tag[KASAN_NR_FREE_STACKS];
193 struct qlist_node *next;
197 * Free meta is stored either in the object itself or in the redzone after the
198 * object. In the former case, free meta offset is 0. In the latter case, the
199 * offset is between 0 and INT_MAX. INT_MAX marks that free meta is not present.
201 #define KASAN_NO_FREE_META INT_MAX
204 * Free meta is only used by Generic mode while the object is in quarantine.
205 * After that, slab allocator stores the freelist pointer in the object.
207 struct kasan_free_meta {
208 #ifdef CONFIG_KASAN_GENERIC
209 struct qlist_node quarantine_link;
210 struct kasan_track free_track;
214 #if IS_ENABLED(CONFIG_KASAN_KUNIT_TEST)
215 /* Used in KUnit-compatible KASAN tests. */
216 struct kunit_kasan_status {
222 struct kasan_alloc_meta *kasan_get_alloc_meta(struct kmem_cache *cache,
224 #ifdef CONFIG_KASAN_GENERIC
225 struct kasan_free_meta *kasan_get_free_meta(struct kmem_cache *cache,
229 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
231 static inline const void *kasan_shadow_to_mem(const void *shadow_addr)
233 return (void *)(((unsigned long)shadow_addr - KASAN_SHADOW_OFFSET)
234 << KASAN_SHADOW_SCALE_SHIFT);
237 static inline bool addr_has_metadata(const void *addr)
239 return (kasan_reset_tag(addr) >=
240 kasan_shadow_to_mem((void *)KASAN_SHADOW_START));
244 * kasan_check_range - Check memory region, and report if invalid access.
245 * @addr: the accessed address
246 * @size: the accessed size
247 * @write: true if access is a write access
248 * @ret_ip: return address
249 * @return: true if access was valid, false if invalid
251 bool kasan_check_range(unsigned long addr, size_t size, bool write,
252 unsigned long ret_ip);
254 #else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
256 static inline bool addr_has_metadata(const void *addr)
258 return (is_vmalloc_addr(addr) || virt_addr_valid(addr));
261 #endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
263 #if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS)
264 void kasan_print_tags(u8 addr_tag, const void *addr);
266 static inline void kasan_print_tags(u8 addr_tag, const void *addr) { }
269 void *kasan_find_first_bad_addr(void *addr, size_t size);
270 const char *kasan_get_bug_type(struct kasan_report_info *info);
271 void kasan_metadata_fetch_row(char *buffer, void *row);
273 #if defined(CONFIG_KASAN_STACK)
274 void kasan_print_address_stack_frame(const void *addr);
276 static inline void kasan_print_address_stack_frame(const void *addr) { }
279 bool kasan_report(unsigned long addr, size_t size,
280 bool is_write, unsigned long ip);
281 void kasan_report_invalid_free(void *object, unsigned long ip, enum kasan_report_type type);
283 struct page *kasan_addr_to_page(const void *addr);
284 struct slab *kasan_addr_to_slab(const void *addr);
286 depot_stack_handle_t kasan_save_stack(gfp_t flags, bool can_alloc);
287 void kasan_set_track(struct kasan_track *track, gfp_t flags);
288 void kasan_set_free_info(struct kmem_cache *cache, void *object, u8 tag);
289 struct kasan_track *kasan_get_free_track(struct kmem_cache *cache,
290 void *object, u8 tag);
292 #if defined(CONFIG_KASAN_GENERIC) && \
293 (defined(CONFIG_SLAB) || defined(CONFIG_SLUB))
294 bool kasan_quarantine_put(struct kmem_cache *cache, void *object);
295 void kasan_quarantine_reduce(void);
296 void kasan_quarantine_remove_cache(struct kmem_cache *cache);
298 static inline bool kasan_quarantine_put(struct kmem_cache *cache, void *object) { return false; }
299 static inline void kasan_quarantine_reduce(void) { }
300 static inline void kasan_quarantine_remove_cache(struct kmem_cache *cache) { }
303 #ifndef arch_kasan_set_tag
304 static inline const void *arch_kasan_set_tag(const void *addr, u8 tag)
309 #ifndef arch_kasan_get_tag
310 #define arch_kasan_get_tag(addr) 0
313 #define set_tag(addr, tag) ((void *)arch_kasan_set_tag((addr), (tag)))
314 #define get_tag(addr) arch_kasan_get_tag(addr)
316 #ifdef CONFIG_KASAN_HW_TAGS
318 #ifndef arch_enable_tagging_sync
319 #define arch_enable_tagging_sync()
321 #ifndef arch_enable_tagging_async
322 #define arch_enable_tagging_async()
324 #ifndef arch_enable_tagging_asymm
325 #define arch_enable_tagging_asymm()
327 #ifndef arch_force_async_tag_fault
328 #define arch_force_async_tag_fault()
330 #ifndef arch_get_random_tag
331 #define arch_get_random_tag() (0xFF)
333 #ifndef arch_get_mem_tag
334 #define arch_get_mem_tag(addr) (0xFF)
336 #ifndef arch_set_mem_tag_range
337 #define arch_set_mem_tag_range(addr, size, tag, init) ((void *)(addr))
340 #define hw_enable_tagging_sync() arch_enable_tagging_sync()
341 #define hw_enable_tagging_async() arch_enable_tagging_async()
342 #define hw_enable_tagging_asymm() arch_enable_tagging_asymm()
343 #define hw_force_async_tag_fault() arch_force_async_tag_fault()
344 #define hw_get_random_tag() arch_get_random_tag()
345 #define hw_get_mem_tag(addr) arch_get_mem_tag(addr)
346 #define hw_set_mem_tag_range(addr, size, tag, init) \
347 arch_set_mem_tag_range((addr), (size), (tag), (init))
349 void kasan_enable_tagging(void);
351 #else /* CONFIG_KASAN_HW_TAGS */
353 #define hw_enable_tagging_sync()
354 #define hw_enable_tagging_async()
355 #define hw_enable_tagging_asymm()
357 static inline void kasan_enable_tagging(void) { }
359 #endif /* CONFIG_KASAN_HW_TAGS */
361 #if defined(CONFIG_KASAN_HW_TAGS) && IS_ENABLED(CONFIG_KASAN_KUNIT_TEST)
363 void kasan_force_async_fault(void);
365 #else /* CONFIG_KASAN_HW_TAGS && CONFIG_KASAN_KUNIT_TEST */
367 static inline void kasan_force_async_fault(void) { }
369 #endif /* CONFIG_KASAN_HW_TAGS && CONFIG_KASAN_KUNIT_TEST */
371 #ifdef CONFIG_KASAN_SW_TAGS
372 u8 kasan_random_tag(void);
373 #elif defined(CONFIG_KASAN_HW_TAGS)
374 static inline u8 kasan_random_tag(void) { return hw_get_random_tag(); }
376 static inline u8 kasan_random_tag(void) { return 0; }
379 #ifdef CONFIG_KASAN_HW_TAGS
381 static inline void kasan_poison(const void *addr, size_t size, u8 value, bool init)
383 addr = kasan_reset_tag(addr);
385 /* Skip KFENCE memory if called explicitly outside of sl*b. */
386 if (is_kfence_address(addr))
389 if (WARN_ON((unsigned long)addr & KASAN_GRANULE_MASK))
391 if (WARN_ON(size & KASAN_GRANULE_MASK))
394 hw_set_mem_tag_range((void *)addr, size, value, init);
397 static inline void kasan_unpoison(const void *addr, size_t size, bool init)
399 u8 tag = get_tag(addr);
401 addr = kasan_reset_tag(addr);
403 /* Skip KFENCE memory if called explicitly outside of sl*b. */
404 if (is_kfence_address(addr))
407 if (WARN_ON((unsigned long)addr & KASAN_GRANULE_MASK))
410 * Explicitly initialize the memory with the precise object size to
411 * avoid overwriting the slab redzone. This disables initialization in
412 * the arch code and may thus lead to performance penalty. This penalty
413 * does not affect production builds, as slab redzones are not enabled
416 if (__slub_debug_enabled() &&
417 init && ((unsigned long)size & KASAN_GRANULE_MASK)) {
419 memzero_explicit((void *)addr, size);
421 size = round_up(size, KASAN_GRANULE_SIZE);
423 hw_set_mem_tag_range((void *)addr, size, tag, init);
426 static inline bool kasan_byte_accessible(const void *addr)
428 u8 ptr_tag = get_tag(addr);
429 u8 mem_tag = hw_get_mem_tag((void *)addr);
431 return ptr_tag == KASAN_TAG_KERNEL || ptr_tag == mem_tag;
434 #else /* CONFIG_KASAN_HW_TAGS */
437 * kasan_poison - mark the memory range as inaccessible
438 * @addr - range start address, must be aligned to KASAN_GRANULE_SIZE
439 * @size - range size, must be aligned to KASAN_GRANULE_SIZE
440 * @value - value that's written to metadata for the range
441 * @init - whether to initialize the memory range (only for hardware tag-based)
443 * The size gets aligned to KASAN_GRANULE_SIZE before marking the range.
445 void kasan_poison(const void *addr, size_t size, u8 value, bool init);
448 * kasan_unpoison - mark the memory range as accessible
449 * @addr - range start address, must be aligned to KASAN_GRANULE_SIZE
450 * @size - range size, can be unaligned
451 * @init - whether to initialize the memory range (only for hardware tag-based)
453 * For the tag-based modes, the @size gets aligned to KASAN_GRANULE_SIZE before
455 * For the generic mode, the last granule of the memory range gets partially
456 * unpoisoned based on the @size.
458 void kasan_unpoison(const void *addr, size_t size, bool init);
460 bool kasan_byte_accessible(const void *addr);
462 #endif /* CONFIG_KASAN_HW_TAGS */
464 #ifdef CONFIG_KASAN_GENERIC
467 * kasan_poison_last_granule - mark the last granule of the memory range as
469 * @addr - range start address, must be aligned to KASAN_GRANULE_SIZE
472 * This function is only available for the generic mode, as it's the only mode
473 * that has partially poisoned memory granules.
475 void kasan_poison_last_granule(const void *address, size_t size);
477 #else /* CONFIG_KASAN_GENERIC */
479 static inline void kasan_poison_last_granule(const void *address, size_t size) { }
481 #endif /* CONFIG_KASAN_GENERIC */
483 #ifndef kasan_arch_is_ready
484 static inline bool kasan_arch_is_ready(void) { return true; }
485 #elif !defined(CONFIG_KASAN_GENERIC) || !defined(CONFIG_KASAN_OUTLINE)
486 #error kasan_arch_is_ready only works in KASAN generic outline mode!
489 #if IS_ENABLED(CONFIG_KASAN_KUNIT_TEST) || IS_ENABLED(CONFIG_KASAN_MODULE_TEST)
491 bool kasan_save_enable_multi_shot(void);
492 void kasan_restore_multi_shot(bool enabled);
497 * Exported functions for interfaces called from assembly or from generated
498 * code. Declared here to avoid warnings about missing declarations.
501 asmlinkage void kasan_unpoison_task_stack_below(const void *watermark);
502 void __asan_register_globals(struct kasan_global *globals, size_t size);
503 void __asan_unregister_globals(struct kasan_global *globals, size_t size);
504 void __asan_handle_no_return(void);
505 void __asan_alloca_poison(unsigned long addr, size_t size);
506 void __asan_allocas_unpoison(const void *stack_top, const void *stack_bottom);
508 void __asan_load1(unsigned long addr);
509 void __asan_store1(unsigned long addr);
510 void __asan_load2(unsigned long addr);
511 void __asan_store2(unsigned long addr);
512 void __asan_load4(unsigned long addr);
513 void __asan_store4(unsigned long addr);
514 void __asan_load8(unsigned long addr);
515 void __asan_store8(unsigned long addr);
516 void __asan_load16(unsigned long addr);
517 void __asan_store16(unsigned long addr);
518 void __asan_loadN(unsigned long addr, size_t size);
519 void __asan_storeN(unsigned long addr, size_t size);
521 void __asan_load1_noabort(unsigned long addr);
522 void __asan_store1_noabort(unsigned long addr);
523 void __asan_load2_noabort(unsigned long addr);
524 void __asan_store2_noabort(unsigned long addr);
525 void __asan_load4_noabort(unsigned long addr);
526 void __asan_store4_noabort(unsigned long addr);
527 void __asan_load8_noabort(unsigned long addr);
528 void __asan_store8_noabort(unsigned long addr);
529 void __asan_load16_noabort(unsigned long addr);
530 void __asan_store16_noabort(unsigned long addr);
531 void __asan_loadN_noabort(unsigned long addr, size_t size);
532 void __asan_storeN_noabort(unsigned long addr, size_t size);
534 void __asan_report_load1_noabort(unsigned long addr);
535 void __asan_report_store1_noabort(unsigned long addr);
536 void __asan_report_load2_noabort(unsigned long addr);
537 void __asan_report_store2_noabort(unsigned long addr);
538 void __asan_report_load4_noabort(unsigned long addr);
539 void __asan_report_store4_noabort(unsigned long addr);
540 void __asan_report_load8_noabort(unsigned long addr);
541 void __asan_report_store8_noabort(unsigned long addr);
542 void __asan_report_load16_noabort(unsigned long addr);
543 void __asan_report_store16_noabort(unsigned long addr);
544 void __asan_report_load_n_noabort(unsigned long addr, size_t size);
545 void __asan_report_store_n_noabort(unsigned long addr, size_t size);
547 void __asan_set_shadow_00(const void *addr, size_t size);
548 void __asan_set_shadow_f1(const void *addr, size_t size);
549 void __asan_set_shadow_f2(const void *addr, size_t size);
550 void __asan_set_shadow_f3(const void *addr, size_t size);
551 void __asan_set_shadow_f5(const void *addr, size_t size);
552 void __asan_set_shadow_f8(const void *addr, size_t size);
554 void __hwasan_load1_noabort(unsigned long addr);
555 void __hwasan_store1_noabort(unsigned long addr);
556 void __hwasan_load2_noabort(unsigned long addr);
557 void __hwasan_store2_noabort(unsigned long addr);
558 void __hwasan_load4_noabort(unsigned long addr);
559 void __hwasan_store4_noabort(unsigned long addr);
560 void __hwasan_load8_noabort(unsigned long addr);
561 void __hwasan_store8_noabort(unsigned long addr);
562 void __hwasan_load16_noabort(unsigned long addr);
563 void __hwasan_store16_noabort(unsigned long addr);
564 void __hwasan_loadN_noabort(unsigned long addr, size_t size);
565 void __hwasan_storeN_noabort(unsigned long addr, size_t size);
567 void __hwasan_tag_memory(unsigned long addr, u8 tag, unsigned long size);
569 #endif /* __MM_KASAN_KASAN_H */