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;
47 static inline bool kasan_stack_collection_enabled(void)
52 static inline bool kasan_async_fault_possible(void)
57 static inline bool kasan_sync_fault_possible(void)
64 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
65 #define KASAN_GRANULE_SIZE (1UL << KASAN_SHADOW_SCALE_SHIFT)
67 #include <asm/mte-kasan.h>
68 #define KASAN_GRANULE_SIZE MTE_GRANULE_SIZE
71 #define KASAN_GRANULE_MASK (KASAN_GRANULE_SIZE - 1)
73 #define KASAN_MEMORY_PER_SHADOW_PAGE (KASAN_GRANULE_SIZE << PAGE_SHIFT)
75 #ifdef CONFIG_KASAN_GENERIC
76 #define KASAN_FREE_PAGE 0xFF /* page was freed */
77 #define KASAN_PAGE_REDZONE 0xFE /* redzone for kmalloc_large allocations */
78 #define KASAN_KMALLOC_REDZONE 0xFC /* redzone inside slub object */
79 #define KASAN_KMALLOC_FREE 0xFB /* object was freed (kmem_cache_free/kfree) */
80 #define KASAN_VMALLOC_INVALID 0xF8 /* unallocated space in vmapped page */
82 #define KASAN_FREE_PAGE KASAN_TAG_INVALID
83 #define KASAN_PAGE_REDZONE KASAN_TAG_INVALID
84 #define KASAN_KMALLOC_REDZONE KASAN_TAG_INVALID
85 #define KASAN_KMALLOC_FREE KASAN_TAG_INVALID
86 #define KASAN_VMALLOC_INVALID KASAN_TAG_INVALID /* only for SW_TAGS */
89 #ifdef CONFIG_KASAN_GENERIC
91 #define KASAN_KMALLOC_FREETRACK 0xFA /* object was freed and has free track set */
92 #define KASAN_GLOBAL_REDZONE 0xF9 /* redzone for global variable */
95 * Stack redzone shadow values
96 * (Those are compiler's ABI, don't change them)
98 #define KASAN_STACK_LEFT 0xF1
99 #define KASAN_STACK_MID 0xF2
100 #define KASAN_STACK_RIGHT 0xF3
101 #define KASAN_STACK_PARTIAL 0xF4
104 * alloca redzone shadow values
106 #define KASAN_ALLOCA_LEFT 0xCA
107 #define KASAN_ALLOCA_RIGHT 0xCB
109 #define KASAN_ALLOCA_REDZONE_SIZE 32
112 * Stack frame marker (compiler ABI).
114 #define KASAN_CURRENT_STACK_FRAME_MAGIC 0x41B58AB3
116 /* Don't break randconfig/all*config builds */
117 #ifndef KASAN_ABI_VERSION
118 #define KASAN_ABI_VERSION 1
121 #endif /* CONFIG_KASAN_GENERIC */
123 /* Metadata layout customization. */
124 #define META_BYTES_PER_BLOCK 1
125 #define META_BLOCKS_PER_ROW 16
126 #define META_BYTES_PER_ROW (META_BLOCKS_PER_ROW * META_BYTES_PER_BLOCK)
127 #define META_MEM_BYTES_PER_ROW (META_BYTES_PER_ROW * KASAN_GRANULE_SIZE)
128 #define META_ROWS_AROUND_ADDR 2
130 enum kasan_report_type {
132 KASAN_REPORT_INVALID_FREE,
135 struct kasan_report_info {
136 enum kasan_report_type type;
138 void *first_bad_addr;
144 /* The layout of struct dictated by compiler */
145 struct kasan_source_location {
146 const char *filename;
151 /* The layout of struct dictated by compiler */
152 struct kasan_global {
153 const void *beg; /* Address of the beginning of the global variable. */
154 size_t size; /* Size of the global variable. */
155 size_t size_with_redzone; /* Size of the variable + size of the red zone. 32 bytes aligned */
157 const void *module_name; /* Name of the module where the global variable is declared. */
158 unsigned long has_dynamic_init; /* This needed for C++ */
159 #if KASAN_ABI_VERSION >= 4
160 struct kasan_source_location *location;
162 #if KASAN_ABI_VERSION >= 5
168 * Structures to keep alloc and free tracks *
171 #define KASAN_STACK_DEPTH 64
175 depot_stack_handle_t stack;
178 #if defined(CONFIG_KASAN_TAGS_IDENTIFY) && defined(CONFIG_KASAN_SW_TAGS)
179 #define KASAN_NR_FREE_STACKS 5
181 #define KASAN_NR_FREE_STACKS 1
184 struct kasan_alloc_meta {
185 struct kasan_track alloc_track;
186 #ifdef CONFIG_KASAN_GENERIC
188 * The auxiliary stack is stored into struct kasan_alloc_meta.
189 * The free stack is stored into struct kasan_free_meta.
191 depot_stack_handle_t aux_stack[2];
193 struct kasan_track free_track[KASAN_NR_FREE_STACKS];
195 #ifdef CONFIG_KASAN_TAGS_IDENTIFY
196 u8 free_pointer_tag[KASAN_NR_FREE_STACKS];
202 struct qlist_node *next;
206 * Generic mode either stores free meta in the object itself or in the redzone
207 * after the object. In the former case free meta offset is 0, in the latter
208 * case it has some sane value smaller than INT_MAX. Use INT_MAX as free meta
209 * offset when free meta isn't present.
211 #define KASAN_NO_FREE_META INT_MAX
213 struct kasan_free_meta {
214 #ifdef CONFIG_KASAN_GENERIC
215 /* This field is used while the object is in the quarantine.
216 * Otherwise it might be used for the allocator freelist.
218 struct qlist_node quarantine_link;
219 struct kasan_track free_track;
223 #if IS_ENABLED(CONFIG_KASAN_KUNIT_TEST)
224 /* Used in KUnit-compatible KASAN tests. */
225 struct kunit_kasan_status {
231 struct kasan_alloc_meta *kasan_get_alloc_meta(struct kmem_cache *cache,
233 #ifdef CONFIG_KASAN_GENERIC
234 struct kasan_free_meta *kasan_get_free_meta(struct kmem_cache *cache,
238 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
240 static inline const void *kasan_shadow_to_mem(const void *shadow_addr)
242 return (void *)(((unsigned long)shadow_addr - KASAN_SHADOW_OFFSET)
243 << KASAN_SHADOW_SCALE_SHIFT);
246 static inline bool addr_has_metadata(const void *addr)
248 return (kasan_reset_tag(addr) >=
249 kasan_shadow_to_mem((void *)KASAN_SHADOW_START));
253 * kasan_check_range - Check memory region, and report if invalid access.
254 * @addr: the accessed address
255 * @size: the accessed size
256 * @write: true if access is a write access
257 * @ret_ip: return address
258 * @return: true if access was valid, false if invalid
260 bool kasan_check_range(unsigned long addr, size_t size, bool write,
261 unsigned long ret_ip);
263 #else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
265 static inline bool addr_has_metadata(const void *addr)
267 return (is_vmalloc_addr(addr) || virt_addr_valid(addr));
270 #endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
272 #if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS)
273 void kasan_print_tags(u8 addr_tag, const void *addr);
275 static inline void kasan_print_tags(u8 addr_tag, const void *addr) { }
278 void *kasan_find_first_bad_addr(void *addr, size_t size);
279 const char *kasan_get_bug_type(struct kasan_report_info *info);
280 void kasan_metadata_fetch_row(char *buffer, void *row);
282 #if defined(CONFIG_KASAN_STACK)
283 void kasan_print_address_stack_frame(const void *addr);
285 static inline void kasan_print_address_stack_frame(const void *addr) { }
288 bool kasan_report(unsigned long addr, size_t size,
289 bool is_write, unsigned long ip);
290 void kasan_report_invalid_free(void *object, unsigned long ip);
292 struct page *kasan_addr_to_page(const void *addr);
293 struct slab *kasan_addr_to_slab(const void *addr);
295 depot_stack_handle_t kasan_save_stack(gfp_t flags, bool can_alloc);
296 void kasan_set_track(struct kasan_track *track, gfp_t flags);
297 void kasan_set_free_info(struct kmem_cache *cache, void *object, u8 tag);
298 struct kasan_track *kasan_get_free_track(struct kmem_cache *cache,
299 void *object, u8 tag);
301 #if defined(CONFIG_KASAN_GENERIC) && \
302 (defined(CONFIG_SLAB) || defined(CONFIG_SLUB))
303 bool kasan_quarantine_put(struct kmem_cache *cache, void *object);
304 void kasan_quarantine_reduce(void);
305 void kasan_quarantine_remove_cache(struct kmem_cache *cache);
307 static inline bool kasan_quarantine_put(struct kmem_cache *cache, void *object) { return false; }
308 static inline void kasan_quarantine_reduce(void) { }
309 static inline void kasan_quarantine_remove_cache(struct kmem_cache *cache) { }
312 #ifndef arch_kasan_set_tag
313 static inline const void *arch_kasan_set_tag(const void *addr, u8 tag)
318 #ifndef arch_kasan_get_tag
319 #define arch_kasan_get_tag(addr) 0
322 #define set_tag(addr, tag) ((void *)arch_kasan_set_tag((addr), (tag)))
323 #define get_tag(addr) arch_kasan_get_tag(addr)
325 #ifdef CONFIG_KASAN_HW_TAGS
327 #ifndef arch_enable_tagging_sync
328 #define arch_enable_tagging_sync()
330 #ifndef arch_enable_tagging_async
331 #define arch_enable_tagging_async()
333 #ifndef arch_enable_tagging_asymm
334 #define arch_enable_tagging_asymm()
336 #ifndef arch_force_async_tag_fault
337 #define arch_force_async_tag_fault()
339 #ifndef arch_get_random_tag
340 #define arch_get_random_tag() (0xFF)
342 #ifndef arch_get_mem_tag
343 #define arch_get_mem_tag(addr) (0xFF)
345 #ifndef arch_set_mem_tag_range
346 #define arch_set_mem_tag_range(addr, size, tag, init) ((void *)(addr))
349 #define hw_enable_tagging_sync() arch_enable_tagging_sync()
350 #define hw_enable_tagging_async() arch_enable_tagging_async()
351 #define hw_enable_tagging_asymm() arch_enable_tagging_asymm()
352 #define hw_force_async_tag_fault() arch_force_async_tag_fault()
353 #define hw_get_random_tag() arch_get_random_tag()
354 #define hw_get_mem_tag(addr) arch_get_mem_tag(addr)
355 #define hw_set_mem_tag_range(addr, size, tag, init) \
356 arch_set_mem_tag_range((addr), (size), (tag), (init))
358 void kasan_enable_tagging(void);
360 #else /* CONFIG_KASAN_HW_TAGS */
362 #define hw_enable_tagging_sync()
363 #define hw_enable_tagging_async()
364 #define hw_enable_tagging_asymm()
366 static inline void kasan_enable_tagging(void) { }
368 #endif /* CONFIG_KASAN_HW_TAGS */
370 #if defined(CONFIG_KASAN_HW_TAGS) && IS_ENABLED(CONFIG_KASAN_KUNIT_TEST)
372 void kasan_force_async_fault(void);
374 #else /* CONFIG_KASAN_HW_TAGS && CONFIG_KASAN_KUNIT_TEST */
376 static inline void kasan_force_async_fault(void) { }
378 #endif /* CONFIG_KASAN_HW_TAGS && CONFIG_KASAN_KUNIT_TEST */
380 #ifdef CONFIG_KASAN_SW_TAGS
381 u8 kasan_random_tag(void);
382 #elif defined(CONFIG_KASAN_HW_TAGS)
383 static inline u8 kasan_random_tag(void) { return hw_get_random_tag(); }
385 static inline u8 kasan_random_tag(void) { return 0; }
388 #ifdef CONFIG_KASAN_HW_TAGS
390 static inline void kasan_poison(const void *addr, size_t size, u8 value, bool init)
392 addr = kasan_reset_tag(addr);
394 /* Skip KFENCE memory if called explicitly outside of sl*b. */
395 if (is_kfence_address(addr))
398 if (WARN_ON((unsigned long)addr & KASAN_GRANULE_MASK))
400 if (WARN_ON(size & KASAN_GRANULE_MASK))
403 hw_set_mem_tag_range((void *)addr, size, value, init);
406 static inline void kasan_unpoison(const void *addr, size_t size, bool init)
408 u8 tag = get_tag(addr);
410 addr = kasan_reset_tag(addr);
412 /* Skip KFENCE memory if called explicitly outside of sl*b. */
413 if (is_kfence_address(addr))
416 if (WARN_ON((unsigned long)addr & KASAN_GRANULE_MASK))
419 * Explicitly initialize the memory with the precise object size to
420 * avoid overwriting the SLAB redzone. This disables initialization in
421 * the arch code and may thus lead to performance penalty. The penalty
422 * is accepted since SLAB redzones aren't enabled in production builds.
424 if (__slub_debug_enabled() &&
425 init && ((unsigned long)size & KASAN_GRANULE_MASK)) {
427 memzero_explicit((void *)addr, size);
429 size = round_up(size, KASAN_GRANULE_SIZE);
431 hw_set_mem_tag_range((void *)addr, size, tag, init);
434 static inline bool kasan_byte_accessible(const void *addr)
436 u8 ptr_tag = get_tag(addr);
437 u8 mem_tag = hw_get_mem_tag((void *)addr);
439 return ptr_tag == KASAN_TAG_KERNEL || ptr_tag == mem_tag;
442 #else /* CONFIG_KASAN_HW_TAGS */
445 * kasan_poison - mark the memory range as inaccessible
446 * @addr - range start address, must be aligned to KASAN_GRANULE_SIZE
447 * @size - range size, must be aligned to KASAN_GRANULE_SIZE
448 * @value - value that's written to metadata for the range
449 * @init - whether to initialize the memory range (only for hardware tag-based)
451 * The size gets aligned to KASAN_GRANULE_SIZE before marking the range.
453 void kasan_poison(const void *addr, size_t size, u8 value, bool init);
456 * kasan_unpoison - mark the memory range as accessible
457 * @addr - range start address, must be aligned to KASAN_GRANULE_SIZE
458 * @size - range size, can be unaligned
459 * @init - whether to initialize the memory range (only for hardware tag-based)
461 * For the tag-based modes, the @size gets aligned to KASAN_GRANULE_SIZE before
463 * For the generic mode, the last granule of the memory range gets partially
464 * unpoisoned based on the @size.
466 void kasan_unpoison(const void *addr, size_t size, bool init);
468 bool kasan_byte_accessible(const void *addr);
470 #endif /* CONFIG_KASAN_HW_TAGS */
472 #ifdef CONFIG_KASAN_GENERIC
475 * kasan_poison_last_granule - mark the last granule of the memory range as
477 * @addr - range start address, must be aligned to KASAN_GRANULE_SIZE
480 * This function is only available for the generic mode, as it's the only mode
481 * that has partially poisoned memory granules.
483 void kasan_poison_last_granule(const void *address, size_t size);
485 #else /* CONFIG_KASAN_GENERIC */
487 static inline void kasan_poison_last_granule(const void *address, size_t size) { }
489 #endif /* CONFIG_KASAN_GENERIC */
491 #ifndef kasan_arch_is_ready
492 static inline bool kasan_arch_is_ready(void) { return true; }
493 #elif !defined(CONFIG_KASAN_GENERIC) || !defined(CONFIG_KASAN_OUTLINE)
494 #error kasan_arch_is_ready only works in KASAN generic outline mode!
497 #if IS_ENABLED(CONFIG_KASAN_KUNIT_TEST) || IS_ENABLED(CONFIG_KASAN_MODULE_TEST)
499 bool kasan_save_enable_multi_shot(void);
500 void kasan_restore_multi_shot(bool enabled);
505 * Exported functions for interfaces called from assembly or from generated
506 * code. Declarations here to avoid warning about missing declarations.
508 asmlinkage void kasan_unpoison_task_stack_below(const void *watermark);
509 void __asan_register_globals(struct kasan_global *globals, size_t size);
510 void __asan_unregister_globals(struct kasan_global *globals, size_t size);
511 void __asan_handle_no_return(void);
512 void __asan_alloca_poison(unsigned long addr, size_t size);
513 void __asan_allocas_unpoison(const void *stack_top, const void *stack_bottom);
515 void __asan_load1(unsigned long addr);
516 void __asan_store1(unsigned long addr);
517 void __asan_load2(unsigned long addr);
518 void __asan_store2(unsigned long addr);
519 void __asan_load4(unsigned long addr);
520 void __asan_store4(unsigned long addr);
521 void __asan_load8(unsigned long addr);
522 void __asan_store8(unsigned long addr);
523 void __asan_load16(unsigned long addr);
524 void __asan_store16(unsigned long addr);
525 void __asan_loadN(unsigned long addr, size_t size);
526 void __asan_storeN(unsigned long addr, size_t size);
528 void __asan_load1_noabort(unsigned long addr);
529 void __asan_store1_noabort(unsigned long addr);
530 void __asan_load2_noabort(unsigned long addr);
531 void __asan_store2_noabort(unsigned long addr);
532 void __asan_load4_noabort(unsigned long addr);
533 void __asan_store4_noabort(unsigned long addr);
534 void __asan_load8_noabort(unsigned long addr);
535 void __asan_store8_noabort(unsigned long addr);
536 void __asan_load16_noabort(unsigned long addr);
537 void __asan_store16_noabort(unsigned long addr);
538 void __asan_loadN_noabort(unsigned long addr, size_t size);
539 void __asan_storeN_noabort(unsigned long addr, size_t size);
541 void __asan_report_load1_noabort(unsigned long addr);
542 void __asan_report_store1_noabort(unsigned long addr);
543 void __asan_report_load2_noabort(unsigned long addr);
544 void __asan_report_store2_noabort(unsigned long addr);
545 void __asan_report_load4_noabort(unsigned long addr);
546 void __asan_report_store4_noabort(unsigned long addr);
547 void __asan_report_load8_noabort(unsigned long addr);
548 void __asan_report_store8_noabort(unsigned long addr);
549 void __asan_report_load16_noabort(unsigned long addr);
550 void __asan_report_store16_noabort(unsigned long addr);
551 void __asan_report_load_n_noabort(unsigned long addr, size_t size);
552 void __asan_report_store_n_noabort(unsigned long addr, size_t size);
554 void __asan_set_shadow_00(const void *addr, size_t size);
555 void __asan_set_shadow_f1(const void *addr, size_t size);
556 void __asan_set_shadow_f2(const void *addr, size_t size);
557 void __asan_set_shadow_f3(const void *addr, size_t size);
558 void __asan_set_shadow_f5(const void *addr, size_t size);
559 void __asan_set_shadow_f8(const void *addr, size_t size);
561 void __hwasan_load1_noabort(unsigned long addr);
562 void __hwasan_store1_noabort(unsigned long addr);
563 void __hwasan_load2_noabort(unsigned long addr);
564 void __hwasan_store2_noabort(unsigned long addr);
565 void __hwasan_load4_noabort(unsigned long addr);
566 void __hwasan_store4_noabort(unsigned long addr);
567 void __hwasan_load8_noabort(unsigned long addr);
568 void __hwasan_store8_noabort(unsigned long addr);
569 void __hwasan_load16_noabort(unsigned long addr);
570 void __hwasan_store16_noabort(unsigned long addr);
571 void __hwasan_loadN_noabort(unsigned long addr, size_t size);
572 void __hwasan_storeN_noabort(unsigned long addr, size_t size);
574 void __hwasan_tag_memory(unsigned long addr, u8 tag, unsigned long size);