1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef __MM_KASAN_KASAN_H 3 #define __MM_KASAN_KASAN_H 4 5 #include <linux/kasan.h> 6 #include <linux/kasan-tags.h> 7 #include <linux/kfence.h> 8 #include <linux/stackdepot.h> 9 10 #ifdef CONFIG_KASAN_HW_TAGS 11 12 #include <linux/static_key.h> 13 #include "../slab.h" 14 15 DECLARE_STATIC_KEY_FALSE(kasan_flag_stacktrace); 16 extern bool kasan_flag_async __ro_after_init; 17 18 static inline bool kasan_stack_collection_enabled(void) 19 { 20 return static_branch_unlikely(&kasan_flag_stacktrace); 21 } 22 23 static inline bool kasan_async_mode_enabled(void) 24 { 25 return kasan_flag_async; 26 } 27 #else 28 29 static inline bool kasan_stack_collection_enabled(void) 30 { 31 return true; 32 } 33 34 static inline bool kasan_async_mode_enabled(void) 35 { 36 return false; 37 } 38 39 #endif 40 41 extern bool kasan_flag_async __ro_after_init; 42 43 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) 44 #define KASAN_GRANULE_SIZE (1UL << KASAN_SHADOW_SCALE_SHIFT) 45 #else 46 #include <asm/mte-kasan.h> 47 #define KASAN_GRANULE_SIZE MTE_GRANULE_SIZE 48 #endif 49 50 #define KASAN_GRANULE_MASK (KASAN_GRANULE_SIZE - 1) 51 52 #define KASAN_MEMORY_PER_SHADOW_PAGE (KASAN_GRANULE_SIZE << PAGE_SHIFT) 53 54 #ifdef CONFIG_KASAN_GENERIC 55 #define KASAN_FREE_PAGE 0xFF /* page was freed */ 56 #define KASAN_PAGE_REDZONE 0xFE /* redzone for kmalloc_large allocations */ 57 #define KASAN_KMALLOC_REDZONE 0xFC /* redzone inside slub object */ 58 #define KASAN_KMALLOC_FREE 0xFB /* object was freed (kmem_cache_free/kfree) */ 59 #define KASAN_KMALLOC_FREETRACK 0xFA /* object was freed and has free track set */ 60 #else 61 #define KASAN_FREE_PAGE KASAN_TAG_INVALID 62 #define KASAN_PAGE_REDZONE KASAN_TAG_INVALID 63 #define KASAN_KMALLOC_REDZONE KASAN_TAG_INVALID 64 #define KASAN_KMALLOC_FREE KASAN_TAG_INVALID 65 #define KASAN_KMALLOC_FREETRACK KASAN_TAG_INVALID 66 #endif 67 68 #define KASAN_GLOBAL_REDZONE 0xF9 /* redzone for global variable */ 69 #define KASAN_VMALLOC_INVALID 0xF8 /* unallocated space in vmapped page */ 70 71 /* 72 * Stack redzone shadow values 73 * (Those are compiler's ABI, don't change them) 74 */ 75 #define KASAN_STACK_LEFT 0xF1 76 #define KASAN_STACK_MID 0xF2 77 #define KASAN_STACK_RIGHT 0xF3 78 #define KASAN_STACK_PARTIAL 0xF4 79 80 /* 81 * alloca redzone shadow values 82 */ 83 #define KASAN_ALLOCA_LEFT 0xCA 84 #define KASAN_ALLOCA_RIGHT 0xCB 85 86 #define KASAN_ALLOCA_REDZONE_SIZE 32 87 88 /* 89 * Stack frame marker (compiler ABI). 90 */ 91 #define KASAN_CURRENT_STACK_FRAME_MAGIC 0x41B58AB3 92 93 /* Don't break randconfig/all*config builds */ 94 #ifndef KASAN_ABI_VERSION 95 #define KASAN_ABI_VERSION 1 96 #endif 97 98 /* Metadata layout customization. */ 99 #define META_BYTES_PER_BLOCK 1 100 #define META_BLOCKS_PER_ROW 16 101 #define META_BYTES_PER_ROW (META_BLOCKS_PER_ROW * META_BYTES_PER_BLOCK) 102 #define META_MEM_BYTES_PER_ROW (META_BYTES_PER_ROW * KASAN_GRANULE_SIZE) 103 #define META_ROWS_AROUND_ADDR 2 104 105 struct kasan_access_info { 106 const void *access_addr; 107 const void *first_bad_addr; 108 size_t access_size; 109 bool is_write; 110 unsigned long ip; 111 }; 112 113 /* The layout of struct dictated by compiler */ 114 struct kasan_source_location { 115 const char *filename; 116 int line_no; 117 int column_no; 118 }; 119 120 /* The layout of struct dictated by compiler */ 121 struct kasan_global { 122 const void *beg; /* Address of the beginning of the global variable. */ 123 size_t size; /* Size of the global variable. */ 124 size_t size_with_redzone; /* Size of the variable + size of the red zone. 32 bytes aligned */ 125 const void *name; 126 const void *module_name; /* Name of the module where the global variable is declared. */ 127 unsigned long has_dynamic_init; /* This needed for C++ */ 128 #if KASAN_ABI_VERSION >= 4 129 struct kasan_source_location *location; 130 #endif 131 #if KASAN_ABI_VERSION >= 5 132 char *odr_indicator; 133 #endif 134 }; 135 136 /** 137 * Structures to keep alloc and free tracks * 138 */ 139 140 #define KASAN_STACK_DEPTH 64 141 142 struct kasan_track { 143 u32 pid; 144 depot_stack_handle_t stack; 145 }; 146 147 #if defined(CONFIG_KASAN_TAGS_IDENTIFY) && defined(CONFIG_KASAN_SW_TAGS) 148 #define KASAN_NR_FREE_STACKS 5 149 #else 150 #define KASAN_NR_FREE_STACKS 1 151 #endif 152 153 struct kasan_alloc_meta { 154 struct kasan_track alloc_track; 155 #ifdef CONFIG_KASAN_GENERIC 156 /* 157 * The auxiliary stack is stored into struct kasan_alloc_meta. 158 * The free stack is stored into struct kasan_free_meta. 159 */ 160 depot_stack_handle_t aux_stack[2]; 161 #else 162 struct kasan_track free_track[KASAN_NR_FREE_STACKS]; 163 #endif 164 #ifdef CONFIG_KASAN_TAGS_IDENTIFY 165 u8 free_pointer_tag[KASAN_NR_FREE_STACKS]; 166 u8 free_track_idx; 167 #endif 168 }; 169 170 struct qlist_node { 171 struct qlist_node *next; 172 }; 173 174 /* 175 * Generic mode either stores free meta in the object itself or in the redzone 176 * after the object. In the former case free meta offset is 0, in the latter 177 * case it has some sane value smaller than INT_MAX. Use INT_MAX as free meta 178 * offset when free meta isn't present. 179 */ 180 #define KASAN_NO_FREE_META INT_MAX 181 182 struct kasan_free_meta { 183 #ifdef CONFIG_KASAN_GENERIC 184 /* This field is used while the object is in the quarantine. 185 * Otherwise it might be used for the allocator freelist. 186 */ 187 struct qlist_node quarantine_link; 188 struct kasan_track free_track; 189 #endif 190 }; 191 192 struct kasan_alloc_meta *kasan_get_alloc_meta(struct kmem_cache *cache, 193 const void *object); 194 #ifdef CONFIG_KASAN_GENERIC 195 struct kasan_free_meta *kasan_get_free_meta(struct kmem_cache *cache, 196 const void *object); 197 #endif 198 199 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) 200 201 static inline const void *kasan_shadow_to_mem(const void *shadow_addr) 202 { 203 return (void *)(((unsigned long)shadow_addr - KASAN_SHADOW_OFFSET) 204 << KASAN_SHADOW_SCALE_SHIFT); 205 } 206 207 static inline bool addr_has_metadata(const void *addr) 208 { 209 return (addr >= kasan_shadow_to_mem((void *)KASAN_SHADOW_START)); 210 } 211 212 /** 213 * kasan_check_range - Check memory region, and report if invalid access. 214 * @addr: the accessed address 215 * @size: the accessed size 216 * @write: true if access is a write access 217 * @ret_ip: return address 218 * @return: true if access was valid, false if invalid 219 */ 220 bool kasan_check_range(unsigned long addr, size_t size, bool write, 221 unsigned long ret_ip); 222 223 #else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */ 224 225 static inline bool addr_has_metadata(const void *addr) 226 { 227 return (is_vmalloc_addr(addr) || virt_addr_valid(addr)); 228 } 229 230 #endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */ 231 232 #if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS) 233 void kasan_print_tags(u8 addr_tag, const void *addr); 234 #else 235 static inline void kasan_print_tags(u8 addr_tag, const void *addr) { } 236 #endif 237 238 void *kasan_find_first_bad_addr(void *addr, size_t size); 239 const char *kasan_get_bug_type(struct kasan_access_info *info); 240 void kasan_metadata_fetch_row(char *buffer, void *row); 241 242 #if defined(CONFIG_KASAN_GENERIC) && defined(CONFIG_KASAN_STACK) 243 void kasan_print_address_stack_frame(const void *addr); 244 #else 245 static inline void kasan_print_address_stack_frame(const void *addr) { } 246 #endif 247 248 bool kasan_report(unsigned long addr, size_t size, 249 bool is_write, unsigned long ip); 250 void kasan_report_invalid_free(void *object, unsigned long ip); 251 252 struct page *kasan_addr_to_page(const void *addr); 253 254 depot_stack_handle_t kasan_save_stack(gfp_t flags); 255 void kasan_set_track(struct kasan_track *track, gfp_t flags); 256 void kasan_set_free_info(struct kmem_cache *cache, void *object, u8 tag); 257 struct kasan_track *kasan_get_free_track(struct kmem_cache *cache, 258 void *object, u8 tag); 259 260 #if defined(CONFIG_KASAN_GENERIC) && \ 261 (defined(CONFIG_SLAB) || defined(CONFIG_SLUB)) 262 bool kasan_quarantine_put(struct kmem_cache *cache, void *object); 263 void kasan_quarantine_reduce(void); 264 void kasan_quarantine_remove_cache(struct kmem_cache *cache); 265 #else 266 static inline bool kasan_quarantine_put(struct kmem_cache *cache, void *object) { return false; } 267 static inline void kasan_quarantine_reduce(void) { } 268 static inline void kasan_quarantine_remove_cache(struct kmem_cache *cache) { } 269 #endif 270 271 #ifndef arch_kasan_set_tag 272 static inline const void *arch_kasan_set_tag(const void *addr, u8 tag) 273 { 274 return addr; 275 } 276 #endif 277 #ifndef arch_kasan_get_tag 278 #define arch_kasan_get_tag(addr) 0 279 #endif 280 281 #define set_tag(addr, tag) ((void *)arch_kasan_set_tag((addr), (tag))) 282 #define get_tag(addr) arch_kasan_get_tag(addr) 283 284 #ifdef CONFIG_KASAN_HW_TAGS 285 286 #ifndef arch_enable_tagging_sync 287 #define arch_enable_tagging_sync() 288 #endif 289 #ifndef arch_enable_tagging_async 290 #define arch_enable_tagging_async() 291 #endif 292 #ifndef arch_force_async_tag_fault 293 #define arch_force_async_tag_fault() 294 #endif 295 #ifndef arch_get_random_tag 296 #define arch_get_random_tag() (0xFF) 297 #endif 298 #ifndef arch_get_mem_tag 299 #define arch_get_mem_tag(addr) (0xFF) 300 #endif 301 #ifndef arch_set_mem_tag_range 302 #define arch_set_mem_tag_range(addr, size, tag, init) ((void *)(addr)) 303 #endif 304 305 #define hw_enable_tagging_sync() arch_enable_tagging_sync() 306 #define hw_enable_tagging_async() arch_enable_tagging_async() 307 #define hw_force_async_tag_fault() arch_force_async_tag_fault() 308 #define hw_get_random_tag() arch_get_random_tag() 309 #define hw_get_mem_tag(addr) arch_get_mem_tag(addr) 310 #define hw_set_mem_tag_range(addr, size, tag, init) \ 311 arch_set_mem_tag_range((addr), (size), (tag), (init)) 312 313 #else /* CONFIG_KASAN_HW_TAGS */ 314 315 #define hw_enable_tagging_sync() 316 #define hw_enable_tagging_async() 317 318 #endif /* CONFIG_KASAN_HW_TAGS */ 319 320 #if defined(CONFIG_KASAN_HW_TAGS) && IS_ENABLED(CONFIG_KASAN_KUNIT_TEST) 321 322 void kasan_enable_tagging_sync(void); 323 void kasan_force_async_fault(void); 324 325 #else /* CONFIG_KASAN_HW_TAGS || CONFIG_KASAN_KUNIT_TEST */ 326 327 static inline void kasan_enable_tagging_sync(void) { } 328 static inline void kasan_force_async_fault(void) { } 329 330 #endif /* CONFIG_KASAN_HW_TAGS || CONFIG_KASAN_KUNIT_TEST */ 331 332 #ifdef CONFIG_KASAN_SW_TAGS 333 u8 kasan_random_tag(void); 334 #elif defined(CONFIG_KASAN_HW_TAGS) 335 static inline u8 kasan_random_tag(void) { return hw_get_random_tag(); } 336 #else 337 static inline u8 kasan_random_tag(void) { return 0; } 338 #endif 339 340 #ifdef CONFIG_KASAN_HW_TAGS 341 342 static inline void kasan_poison(const void *addr, size_t size, u8 value, bool init) 343 { 344 addr = kasan_reset_tag(addr); 345 346 /* Skip KFENCE memory if called explicitly outside of sl*b. */ 347 if (is_kfence_address(addr)) 348 return; 349 350 if (WARN_ON((unsigned long)addr & KASAN_GRANULE_MASK)) 351 return; 352 if (WARN_ON(size & KASAN_GRANULE_MASK)) 353 return; 354 355 hw_set_mem_tag_range((void *)addr, size, value, init); 356 } 357 358 static inline void kasan_unpoison(const void *addr, size_t size, bool init) 359 { 360 u8 tag = get_tag(addr); 361 362 addr = kasan_reset_tag(addr); 363 364 /* Skip KFENCE memory if called explicitly outside of sl*b. */ 365 if (is_kfence_address(addr)) 366 return; 367 368 if (WARN_ON((unsigned long)addr & KASAN_GRANULE_MASK)) 369 return; 370 /* 371 * Explicitly initialize the memory with the precise object size to 372 * avoid overwriting the SLAB redzone. This disables initialization in 373 * the arch code and may thus lead to performance penalty. The penalty 374 * is accepted since SLAB redzones aren't enabled in production builds. 375 */ 376 if (__slub_debug_enabled() && 377 init && ((unsigned long)size & KASAN_GRANULE_MASK)) { 378 init = false; 379 memzero_explicit((void *)addr, size); 380 } 381 size = round_up(size, KASAN_GRANULE_SIZE); 382 383 hw_set_mem_tag_range((void *)addr, size, tag, init); 384 } 385 386 static inline bool kasan_byte_accessible(const void *addr) 387 { 388 u8 ptr_tag = get_tag(addr); 389 u8 mem_tag = hw_get_mem_tag((void *)addr); 390 391 return ptr_tag == KASAN_TAG_KERNEL || ptr_tag == mem_tag; 392 } 393 394 #else /* CONFIG_KASAN_HW_TAGS */ 395 396 /** 397 * kasan_poison - mark the memory range as inaccessible 398 * @addr - range start address, must be aligned to KASAN_GRANULE_SIZE 399 * @size - range size, must be aligned to KASAN_GRANULE_SIZE 400 * @value - value that's written to metadata for the range 401 * @init - whether to initialize the memory range (only for hardware tag-based) 402 * 403 * The size gets aligned to KASAN_GRANULE_SIZE before marking the range. 404 */ 405 void kasan_poison(const void *addr, size_t size, u8 value, bool init); 406 407 /** 408 * kasan_unpoison - mark the memory range as accessible 409 * @addr - range start address, must be aligned to KASAN_GRANULE_SIZE 410 * @size - range size, can be unaligned 411 * @init - whether to initialize the memory range (only for hardware tag-based) 412 * 413 * For the tag-based modes, the @size gets aligned to KASAN_GRANULE_SIZE before 414 * marking the range. 415 * For the generic mode, the last granule of the memory range gets partially 416 * unpoisoned based on the @size. 417 */ 418 void kasan_unpoison(const void *addr, size_t size, bool init); 419 420 bool kasan_byte_accessible(const void *addr); 421 422 #endif /* CONFIG_KASAN_HW_TAGS */ 423 424 #ifdef CONFIG_KASAN_GENERIC 425 426 /** 427 * kasan_poison_last_granule - mark the last granule of the memory range as 428 * inaccessible 429 * @addr - range start address, must be aligned to KASAN_GRANULE_SIZE 430 * @size - range size 431 * 432 * This function is only available for the generic mode, as it's the only mode 433 * that has partially poisoned memory granules. 434 */ 435 void kasan_poison_last_granule(const void *address, size_t size); 436 437 #else /* CONFIG_KASAN_GENERIC */ 438 439 static inline void kasan_poison_last_granule(const void *address, size_t size) { } 440 441 #endif /* CONFIG_KASAN_GENERIC */ 442 443 #ifndef kasan_arch_is_ready 444 static inline bool kasan_arch_is_ready(void) { return true; } 445 #elif !defined(CONFIG_KASAN_GENERIC) || !defined(CONFIG_KASAN_OUTLINE) 446 #error kasan_arch_is_ready only works in KASAN generic outline mode! 447 #endif 448 449 /* 450 * Exported functions for interfaces called from assembly or from generated 451 * code. Declarations here to avoid warning about missing declarations. 452 */ 453 asmlinkage void kasan_unpoison_task_stack_below(const void *watermark); 454 void __asan_register_globals(struct kasan_global *globals, size_t size); 455 void __asan_unregister_globals(struct kasan_global *globals, size_t size); 456 void __asan_handle_no_return(void); 457 void __asan_alloca_poison(unsigned long addr, size_t size); 458 void __asan_allocas_unpoison(const void *stack_top, const void *stack_bottom); 459 460 void __asan_load1(unsigned long addr); 461 void __asan_store1(unsigned long addr); 462 void __asan_load2(unsigned long addr); 463 void __asan_store2(unsigned long addr); 464 void __asan_load4(unsigned long addr); 465 void __asan_store4(unsigned long addr); 466 void __asan_load8(unsigned long addr); 467 void __asan_store8(unsigned long addr); 468 void __asan_load16(unsigned long addr); 469 void __asan_store16(unsigned long addr); 470 void __asan_loadN(unsigned long addr, size_t size); 471 void __asan_storeN(unsigned long addr, size_t size); 472 473 void __asan_load1_noabort(unsigned long addr); 474 void __asan_store1_noabort(unsigned long addr); 475 void __asan_load2_noabort(unsigned long addr); 476 void __asan_store2_noabort(unsigned long addr); 477 void __asan_load4_noabort(unsigned long addr); 478 void __asan_store4_noabort(unsigned long addr); 479 void __asan_load8_noabort(unsigned long addr); 480 void __asan_store8_noabort(unsigned long addr); 481 void __asan_load16_noabort(unsigned long addr); 482 void __asan_store16_noabort(unsigned long addr); 483 void __asan_loadN_noabort(unsigned long addr, size_t size); 484 void __asan_storeN_noabort(unsigned long addr, size_t size); 485 486 void __asan_report_load1_noabort(unsigned long addr); 487 void __asan_report_store1_noabort(unsigned long addr); 488 void __asan_report_load2_noabort(unsigned long addr); 489 void __asan_report_store2_noabort(unsigned long addr); 490 void __asan_report_load4_noabort(unsigned long addr); 491 void __asan_report_store4_noabort(unsigned long addr); 492 void __asan_report_load8_noabort(unsigned long addr); 493 void __asan_report_store8_noabort(unsigned long addr); 494 void __asan_report_load16_noabort(unsigned long addr); 495 void __asan_report_store16_noabort(unsigned long addr); 496 void __asan_report_load_n_noabort(unsigned long addr, size_t size); 497 void __asan_report_store_n_noabort(unsigned long addr, size_t size); 498 499 void __asan_set_shadow_00(const void *addr, size_t size); 500 void __asan_set_shadow_f1(const void *addr, size_t size); 501 void __asan_set_shadow_f2(const void *addr, size_t size); 502 void __asan_set_shadow_f3(const void *addr, size_t size); 503 void __asan_set_shadow_f5(const void *addr, size_t size); 504 void __asan_set_shadow_f8(const void *addr, size_t size); 505 506 void __hwasan_load1_noabort(unsigned long addr); 507 void __hwasan_store1_noabort(unsigned long addr); 508 void __hwasan_load2_noabort(unsigned long addr); 509 void __hwasan_store2_noabort(unsigned long addr); 510 void __hwasan_load4_noabort(unsigned long addr); 511 void __hwasan_store4_noabort(unsigned long addr); 512 void __hwasan_load8_noabort(unsigned long addr); 513 void __hwasan_store8_noabort(unsigned long addr); 514 void __hwasan_load16_noabort(unsigned long addr); 515 void __hwasan_store16_noabort(unsigned long addr); 516 void __hwasan_loadN_noabort(unsigned long addr, size_t size); 517 void __hwasan_storeN_noabort(unsigned long addr, size_t size); 518 519 void __hwasan_tag_memory(unsigned long addr, u8 tag, unsigned long size); 520 521 #endif 522