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1/* SPDX-License-Identifier: GPL-2.0 */2#ifndef __MM_KASAN_KASAN_H3#define __MM_KASAN_KASAN_H4 5#include <linux/atomic.h>6#include <linux/kasan.h>7#include <linux/kasan-tags.h>8#include <linux/kfence.h>9#include <linux/stackdepot.h>10 11#if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS)12 13#include <linux/static_key.h>14 15DECLARE_STATIC_KEY_TRUE(kasan_flag_stacktrace);16 17static inline bool kasan_stack_collection_enabled(void)18{19 return static_branch_unlikely(&kasan_flag_stacktrace);20}21 22#else /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */23 24static inline bool kasan_stack_collection_enabled(void)25{26 return true;27}28 29#endif /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */30 31#ifdef CONFIG_KASAN_HW_TAGS32 33#include "../slab.h"34 35DECLARE_STATIC_KEY_TRUE(kasan_flag_vmalloc);36 37enum kasan_mode {38 KASAN_MODE_SYNC,39 KASAN_MODE_ASYNC,40 KASAN_MODE_ASYMM,41};42 43extern enum kasan_mode kasan_mode __ro_after_init;44 45extern unsigned long kasan_page_alloc_sample;46extern unsigned int kasan_page_alloc_sample_order;47DECLARE_PER_CPU(long, kasan_page_alloc_skip);48 49static inline bool kasan_vmalloc_enabled(void)50{51 /* Static branch is never enabled with CONFIG_KASAN_VMALLOC disabled. */52 return static_branch_likely(&kasan_flag_vmalloc);53}54 55static inline bool kasan_async_fault_possible(void)56{57 return kasan_mode == KASAN_MODE_ASYNC || kasan_mode == KASAN_MODE_ASYMM;58}59 60static inline bool kasan_sync_fault_possible(void)61{62 return kasan_mode == KASAN_MODE_SYNC || kasan_mode == KASAN_MODE_ASYMM;63}64 65static inline bool kasan_sample_page_alloc(unsigned int order)66{67 /* Fast-path for when sampling is disabled. */68 if (kasan_page_alloc_sample == 1)69 return true;70 71 if (order < kasan_page_alloc_sample_order)72 return true;73 74 if (this_cpu_dec_return(kasan_page_alloc_skip) < 0) {75 this_cpu_write(kasan_page_alloc_skip,76 kasan_page_alloc_sample - 1);77 return true;78 }79 80 return false;81}82 83#else /* CONFIG_KASAN_HW_TAGS */84 85static inline bool kasan_vmalloc_enabled(void)86{87 return IS_ENABLED(CONFIG_KASAN_VMALLOC);88}89 90static inline bool kasan_async_fault_possible(void)91{92 return false;93}94 95static inline bool kasan_sync_fault_possible(void)96{97 return true;98}99 100static inline bool kasan_sample_page_alloc(unsigned int order)101{102 return true;103}104 105#endif /* CONFIG_KASAN_HW_TAGS */106 107#ifdef CONFIG_KASAN_GENERIC108 109/*110 * Generic KASAN uses per-object metadata to store alloc and free stack traces111 * and the quarantine link.112 */113static inline bool kasan_requires_meta(void)114{115 return true;116}117 118#else /* CONFIG_KASAN_GENERIC */119 120/*121 * Tag-based KASAN modes do not use per-object metadata: they use the stack122 * ring to store alloc and free stack traces and do not use qurantine.123 */124static inline bool kasan_requires_meta(void)125{126 return false;127}128 129#endif /* CONFIG_KASAN_GENERIC */130 131#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)132#define KASAN_GRANULE_SIZE (1UL << KASAN_SHADOW_SCALE_SHIFT)133#else134#include <asm/mte-kasan.h>135#define KASAN_GRANULE_SIZE MTE_GRANULE_SIZE136#endif137 138#define KASAN_GRANULE_MASK (KASAN_GRANULE_SIZE - 1)139 140#define KASAN_MEMORY_PER_SHADOW_PAGE (KASAN_GRANULE_SIZE << PAGE_SHIFT)141 142#ifdef CONFIG_KASAN_GENERIC143#define KASAN_PAGE_FREE 0xFF /* freed page */144#define KASAN_PAGE_REDZONE 0xFE /* redzone for kmalloc_large allocation */145#define KASAN_SLAB_REDZONE 0xFC /* redzone for slab object */146#define KASAN_SLAB_FREE 0xFB /* freed slab object */147#define KASAN_VMALLOC_INVALID 0xF8 /* inaccessible space in vmap area */148#else149#define KASAN_PAGE_FREE KASAN_TAG_INVALID150#define KASAN_PAGE_REDZONE KASAN_TAG_INVALID151#define KASAN_SLAB_REDZONE KASAN_TAG_INVALID152#define KASAN_SLAB_FREE KASAN_TAG_INVALID153#define KASAN_VMALLOC_INVALID KASAN_TAG_INVALID /* only used for SW_TAGS */154#endif155 156#ifdef CONFIG_KASAN_GENERIC157 158#define KASAN_SLAB_FREE_META 0xFA /* freed slab object with free meta */159#define KASAN_GLOBAL_REDZONE 0xF9 /* redzone for global variable */160 161/* Stack redzone shadow values. Compiler ABI, do not change. */162#define KASAN_STACK_LEFT 0xF1163#define KASAN_STACK_MID 0xF2164#define KASAN_STACK_RIGHT 0xF3165#define KASAN_STACK_PARTIAL 0xF4166 167/* alloca redzone shadow values. */168#define KASAN_ALLOCA_LEFT 0xCA169#define KASAN_ALLOCA_RIGHT 0xCB170 171/* alloca redzone size. Compiler ABI, do not change. */172#define KASAN_ALLOCA_REDZONE_SIZE 32173 174/* Stack frame marker. Compiler ABI, do not change. */175#define KASAN_CURRENT_STACK_FRAME_MAGIC 0x41B58AB3176 177/* Dummy value to avoid breaking randconfig/all*config builds. */178#ifndef KASAN_ABI_VERSION179#define KASAN_ABI_VERSION 1180#endif181 182#endif /* CONFIG_KASAN_GENERIC */183 184/* Metadata layout customization. */185#define META_BYTES_PER_BLOCK 1186#define META_BLOCKS_PER_ROW 16187#define META_BYTES_PER_ROW (META_BLOCKS_PER_ROW * META_BYTES_PER_BLOCK)188#define META_MEM_BYTES_PER_ROW (META_BYTES_PER_ROW * KASAN_GRANULE_SIZE)189#define META_ROWS_AROUND_ADDR 2190 191#define KASAN_STACK_DEPTH 64192 193struct kasan_track {194 u32 pid;195 depot_stack_handle_t stack;196#ifdef CONFIG_KASAN_EXTRA_INFO197 u64 cpu:20;198 u64 timestamp:44;199#endif /* CONFIG_KASAN_EXTRA_INFO */200};201 202enum kasan_report_type {203 KASAN_REPORT_ACCESS,204 KASAN_REPORT_INVALID_FREE,205 KASAN_REPORT_DOUBLE_FREE,206};207 208struct kasan_report_info {209 /* Filled in by kasan_report_*(). */210 enum kasan_report_type type;211 const void *access_addr;212 size_t access_size;213 bool is_write;214 unsigned long ip;215 216 /* Filled in by the common reporting code. */217 const void *first_bad_addr;218 struct kmem_cache *cache;219 void *object;220 size_t alloc_size;221 222 /* Filled in by the mode-specific reporting code. */223 const char *bug_type;224 struct kasan_track alloc_track;225 struct kasan_track free_track;226};227 228/* Do not change the struct layout: compiler ABI. */229struct kasan_source_location {230 const char *filename;231 int line_no;232 int column_no;233};234 235/* Do not change the struct layout: compiler ABI. */236struct kasan_global {237 const void *beg; /* Address of the beginning of the global variable. */238 size_t size; /* Size of the global variable. */239 size_t size_with_redzone; /* Size of the variable + size of the redzone. 32 bytes aligned. */240 const void *name;241 const void *module_name; /* Name of the module where the global variable is declared. */242 unsigned long has_dynamic_init; /* This is needed for C++. */243#if KASAN_ABI_VERSION >= 4244 struct kasan_source_location *location;245#endif246#if KASAN_ABI_VERSION >= 5247 char *odr_indicator;248#endif249};250 251/* Structures for keeping alloc and free meta. */252 253#ifdef CONFIG_KASAN_GENERIC254 255/*256 * Alloc meta contains the allocation-related information about a slab object.257 * Alloc meta is saved when an object is allocated and is kept until either the258 * object returns to the slab freelist (leaves quarantine for quarantined259 * objects or gets freed for the non-quarantined ones) or reallocated via260 * krealloc or through a mempool.261 * Alloc meta is stored inside of the object's redzone.262 * Alloc meta is considered valid whenever it contains non-zero data.263 */264struct kasan_alloc_meta {265 struct kasan_track alloc_track;266 /* Free track is stored in kasan_free_meta. */267 depot_stack_handle_t aux_stack[2];268};269 270struct qlist_node {271 struct qlist_node *next;272};273 274/*275 * Free meta is stored either in the object itself or in the redzone after the276 * object. In the former case, free meta offset is 0. In the latter case, the277 * offset is between 0 and INT_MAX. INT_MAX marks that free meta is not present.278 */279#define KASAN_NO_FREE_META INT_MAX280 281/*282 * Free meta contains the freeing-related information about a slab object.283 * Free meta is only kept for quarantined objects and for mempool objects until284 * the object gets allocated again.285 * Free meta is stored within the object's memory.286 * Free meta is considered valid whenever the value of the shadow byte that287 * corresponds to the first 8 bytes of the object is KASAN_SLAB_FREE_META.288 */289struct kasan_free_meta {290 struct qlist_node quarantine_link;291 struct kasan_track free_track;292};293 294#endif /* CONFIG_KASAN_GENERIC */295 296#if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS)297 298struct kasan_stack_ring_entry {299 void *ptr;300 size_t size;301 struct kasan_track track;302 bool is_free;303};304 305struct kasan_stack_ring {306 rwlock_t lock;307 size_t size;308 atomic64_t pos;309 struct kasan_stack_ring_entry *entries;310};311 312#endif /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */313 314#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)315 316static __always_inline bool addr_in_shadow(const void *addr)317{318 return addr >= (void *)KASAN_SHADOW_START &&319 addr < (void *)KASAN_SHADOW_END;320}321 322#ifndef kasan_shadow_to_mem323static inline const void *kasan_shadow_to_mem(const void *shadow_addr)324{325 return (void *)(((unsigned long)shadow_addr - KASAN_SHADOW_OFFSET)326 << KASAN_SHADOW_SCALE_SHIFT);327}328#endif329 330#ifndef addr_has_metadata331static __always_inline bool addr_has_metadata(const void *addr)332{333 return (kasan_reset_tag(addr) >=334 kasan_shadow_to_mem((void *)KASAN_SHADOW_START));335}336#endif337 338/**339 * kasan_check_range - Check memory region, and report if invalid access.340 * @addr: the accessed address341 * @size: the accessed size342 * @write: true if access is a write access343 * @ret_ip: return address344 * @return: true if access was valid, false if invalid345 */346bool kasan_check_range(const void *addr, size_t size, bool write,347 unsigned long ret_ip);348 349#else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */350 351static __always_inline bool addr_has_metadata(const void *addr)352{353 return (is_vmalloc_addr(addr) || virt_addr_valid(addr));354}355 356#endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */357 358const void *kasan_find_first_bad_addr(const void *addr, size_t size);359size_t kasan_get_alloc_size(void *object, struct kmem_cache *cache);360void kasan_complete_mode_report_info(struct kasan_report_info *info);361void kasan_metadata_fetch_row(char *buffer, void *row);362 363#if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS)364void kasan_print_tags(u8 addr_tag, const void *addr);365#else366static inline void kasan_print_tags(u8 addr_tag, const void *addr) { }367#endif368 369#if defined(CONFIG_KASAN_STACK)370void kasan_print_address_stack_frame(const void *addr);371#else372static inline void kasan_print_address_stack_frame(const void *addr) { }373#endif374 375#ifdef CONFIG_KASAN_GENERIC376void kasan_print_aux_stacks(struct kmem_cache *cache, const void *object);377#else378static inline void kasan_print_aux_stacks(struct kmem_cache *cache, const void *object) { }379#endif380 381bool kasan_report(const void *addr, size_t size,382 bool is_write, unsigned long ip);383void kasan_report_invalid_free(void *object, unsigned long ip, enum kasan_report_type type);384 385struct slab *kasan_addr_to_slab(const void *addr);386 387#ifdef CONFIG_KASAN_GENERIC388struct kasan_alloc_meta *kasan_get_alloc_meta(struct kmem_cache *cache,389 const void *object);390struct kasan_free_meta *kasan_get_free_meta(struct kmem_cache *cache,391 const void *object);392void kasan_init_object_meta(struct kmem_cache *cache, const void *object);393#else394static inline void kasan_init_object_meta(struct kmem_cache *cache, const void *object) { }395#endif396 397depot_stack_handle_t kasan_save_stack(gfp_t flags, depot_flags_t depot_flags);398void kasan_set_track(struct kasan_track *track, depot_stack_handle_t stack);399void kasan_save_track(struct kasan_track *track, gfp_t flags);400void kasan_save_alloc_info(struct kmem_cache *cache, void *object, gfp_t flags);401void kasan_save_free_info(struct kmem_cache *cache, void *object);402 403#ifdef CONFIG_KASAN_GENERIC404bool kasan_quarantine_put(struct kmem_cache *cache, void *object);405void kasan_quarantine_reduce(void);406void kasan_quarantine_remove_cache(struct kmem_cache *cache);407#else408static inline bool kasan_quarantine_put(struct kmem_cache *cache, void *object) { return false; }409static inline void kasan_quarantine_reduce(void) { }410static inline void kasan_quarantine_remove_cache(struct kmem_cache *cache) { }411#endif412 413#ifndef arch_kasan_set_tag414static inline const void *arch_kasan_set_tag(const void *addr, u8 tag)415{416 return addr;417}418#endif419#ifndef arch_kasan_get_tag420#define arch_kasan_get_tag(addr) 0421#endif422 423#define set_tag(addr, tag) ((void *)arch_kasan_set_tag((addr), (tag)))424#define get_tag(addr) arch_kasan_get_tag(addr)425 426#ifdef CONFIG_KASAN_HW_TAGS427 428#define hw_enable_tag_checks_sync() arch_enable_tag_checks_sync()429#define hw_enable_tag_checks_async() arch_enable_tag_checks_async()430#define hw_enable_tag_checks_asymm() arch_enable_tag_checks_asymm()431#define hw_suppress_tag_checks_start() arch_suppress_tag_checks_start()432#define hw_suppress_tag_checks_stop() arch_suppress_tag_checks_stop()433#define hw_force_async_tag_fault() arch_force_async_tag_fault()434#define hw_get_random_tag() arch_get_random_tag()435#define hw_get_mem_tag(addr) arch_get_mem_tag(addr)436#define hw_set_mem_tag_range(addr, size, tag, init) \437 arch_set_mem_tag_range((addr), (size), (tag), (init))438 439void kasan_enable_hw_tags(void);440 441#else /* CONFIG_KASAN_HW_TAGS */442 443static inline void kasan_enable_hw_tags(void) { }444 445#endif /* CONFIG_KASAN_HW_TAGS */446 447#if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS)448void __init kasan_init_tags(void);449#endif /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */450 451#if defined(CONFIG_KASAN_HW_TAGS) && IS_ENABLED(CONFIG_KASAN_KUNIT_TEST)452 453void kasan_force_async_fault(void);454 455#else /* CONFIG_KASAN_HW_TAGS && CONFIG_KASAN_KUNIT_TEST */456 457static inline void kasan_force_async_fault(void) { }458 459#endif /* CONFIG_KASAN_HW_TAGS && CONFIG_KASAN_KUNIT_TEST */460 461#ifdef CONFIG_KASAN_SW_TAGS462u8 kasan_random_tag(void);463#elif defined(CONFIG_KASAN_HW_TAGS)464static inline u8 kasan_random_tag(void) { return hw_get_random_tag(); }465#else466static inline u8 kasan_random_tag(void) { return 0; }467#endif468 469#ifdef CONFIG_KASAN_HW_TAGS470 471static inline void kasan_poison(const void *addr, size_t size, u8 value, bool init)472{473 if (WARN_ON((unsigned long)addr & KASAN_GRANULE_MASK))474 return;475 if (WARN_ON(size & KASAN_GRANULE_MASK))476 return;477 478 hw_set_mem_tag_range(kasan_reset_tag(addr), size, value, init);479}480 481static inline void kasan_unpoison(const void *addr, size_t size, bool init)482{483 u8 tag = get_tag(addr);484 485 if (WARN_ON((unsigned long)addr & KASAN_GRANULE_MASK))486 return;487 size = round_up(size, KASAN_GRANULE_SIZE);488 489 hw_set_mem_tag_range(kasan_reset_tag(addr), size, tag, init);490}491 492static inline bool kasan_byte_accessible(const void *addr)493{494 u8 ptr_tag = get_tag(addr);495 u8 mem_tag = hw_get_mem_tag((void *)addr);496 497 return ptr_tag == KASAN_TAG_KERNEL || ptr_tag == mem_tag;498}499 500#else /* CONFIG_KASAN_HW_TAGS */501 502/**503 * kasan_poison - mark the memory range as inaccessible504 * @addr - range start address, must be aligned to KASAN_GRANULE_SIZE505 * @size - range size, must be aligned to KASAN_GRANULE_SIZE506 * @value - value that's written to metadata for the range507 * @init - whether to initialize the memory range (only for hardware tag-based)508 */509void kasan_poison(const void *addr, size_t size, u8 value, bool init);510 511/**512 * kasan_unpoison - mark the memory range as accessible513 * @addr - range start address, must be aligned to KASAN_GRANULE_SIZE514 * @size - range size, can be unaligned515 * @init - whether to initialize the memory range (only for hardware tag-based)516 *517 * For the tag-based modes, the @size gets aligned to KASAN_GRANULE_SIZE before518 * marking the range.519 * For the generic mode, the last granule of the memory range gets partially520 * unpoisoned based on the @size.521 */522void kasan_unpoison(const void *addr, size_t size, bool init);523 524bool kasan_byte_accessible(const void *addr);525 526#endif /* CONFIG_KASAN_HW_TAGS */527 528#ifdef CONFIG_KASAN_GENERIC529 530/**531 * kasan_poison_last_granule - mark the last granule of the memory range as532 * inaccessible533 * @addr - range start address, must be aligned to KASAN_GRANULE_SIZE534 * @size - range size535 *536 * This function is only available for the generic mode, as it's the only mode537 * that has partially poisoned memory granules.538 */539void kasan_poison_last_granule(const void *address, size_t size);540 541#else /* CONFIG_KASAN_GENERIC */542 543static inline void kasan_poison_last_granule(const void *address, size_t size) { }544 545#endif /* CONFIG_KASAN_GENERIC */546 547#ifndef kasan_arch_is_ready548static inline bool kasan_arch_is_ready(void) { return true; }549#elif !defined(CONFIG_KASAN_GENERIC) || !defined(CONFIG_KASAN_OUTLINE)550#error kasan_arch_is_ready only works in KASAN generic outline mode!551#endif552 553#if IS_ENABLED(CONFIG_KASAN_KUNIT_TEST)554 555void kasan_kunit_test_suite_start(void);556void kasan_kunit_test_suite_end(void);557 558#ifdef CONFIG_RUST559char kasan_test_rust_uaf(void);560#else561static inline char kasan_test_rust_uaf(void) { return '\0'; }562#endif563 564#else /* CONFIG_KASAN_KUNIT_TEST */565 566static inline void kasan_kunit_test_suite_start(void) { }567static inline void kasan_kunit_test_suite_end(void) { }568 569#endif /* CONFIG_KASAN_KUNIT_TEST */570 571#if IS_ENABLED(CONFIG_KASAN_KUNIT_TEST) || IS_ENABLED(CONFIG_KASAN_MODULE_TEST)572 573bool kasan_save_enable_multi_shot(void);574void kasan_restore_multi_shot(bool enabled);575 576#endif577 578/*579 * Exported functions for interfaces called from assembly or from generated580 * code. Declared here to avoid warnings about missing declarations.581 */582 583void __asan_register_globals(void *globals, ssize_t size);584void __asan_unregister_globals(void *globals, ssize_t size);585void __asan_handle_no_return(void);586void __asan_alloca_poison(void *, ssize_t size);587void __asan_allocas_unpoison(void *stack_top, ssize_t stack_bottom);588 589void __asan_load1(void *);590void __asan_store1(void *);591void __asan_load2(void *);592void __asan_store2(void *);593void __asan_load4(void *);594void __asan_store4(void *);595void __asan_load8(void *);596void __asan_store8(void *);597void __asan_load16(void *);598void __asan_store16(void *);599void __asan_loadN(void *, ssize_t size);600void __asan_storeN(void *, ssize_t size);601 602void __asan_load1_noabort(void *);603void __asan_store1_noabort(void *);604void __asan_load2_noabort(void *);605void __asan_store2_noabort(void *);606void __asan_load4_noabort(void *);607void __asan_store4_noabort(void *);608void __asan_load8_noabort(void *);609void __asan_store8_noabort(void *);610void __asan_load16_noabort(void *);611void __asan_store16_noabort(void *);612void __asan_loadN_noabort(void *, ssize_t size);613void __asan_storeN_noabort(void *, ssize_t size);614 615void __asan_report_load1_noabort(void *);616void __asan_report_store1_noabort(void *);617void __asan_report_load2_noabort(void *);618void __asan_report_store2_noabort(void *);619void __asan_report_load4_noabort(void *);620void __asan_report_store4_noabort(void *);621void __asan_report_load8_noabort(void *);622void __asan_report_store8_noabort(void *);623void __asan_report_load16_noabort(void *);624void __asan_report_store16_noabort(void *);625void __asan_report_load_n_noabort(void *, ssize_t size);626void __asan_report_store_n_noabort(void *, ssize_t size);627 628void __asan_set_shadow_00(const void *addr, ssize_t size);629void __asan_set_shadow_f1(const void *addr, ssize_t size);630void __asan_set_shadow_f2(const void *addr, ssize_t size);631void __asan_set_shadow_f3(const void *addr, ssize_t size);632void __asan_set_shadow_f5(const void *addr, ssize_t size);633void __asan_set_shadow_f8(const void *addr, ssize_t size);634 635void *__asan_memset(void *addr, int c, ssize_t len);636void *__asan_memmove(void *dest, const void *src, ssize_t len);637void *__asan_memcpy(void *dest, const void *src, ssize_t len);638 639void __hwasan_load1_noabort(void *);640void __hwasan_store1_noabort(void *);641void __hwasan_load2_noabort(void *);642void __hwasan_store2_noabort(void *);643void __hwasan_load4_noabort(void *);644void __hwasan_store4_noabort(void *);645void __hwasan_load8_noabort(void *);646void __hwasan_store8_noabort(void *);647void __hwasan_load16_noabort(void *);648void __hwasan_store16_noabort(void *);649void __hwasan_loadN_noabort(void *, ssize_t size);650void __hwasan_storeN_noabort(void *, ssize_t size);651 652void __hwasan_tag_memory(void *, u8 tag, ssize_t size);653 654void *__hwasan_memset(void *addr, int c, ssize_t len);655void *__hwasan_memmove(void *dest, const void *src, ssize_t len);656void *__hwasan_memcpy(void *dest, const void *src, ssize_t len);657 658void kasan_tag_mismatch(void *addr, unsigned long access_info,659 unsigned long ret_ip);660 661#endif /* __MM_KASAN_KASAN_H */662