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/kfence.h> 7 #include <linux/stackdepot.h> 8 9 #ifdef CONFIG_KASAN_HW_TAGS 10 11 #include <linux/static_key.h> 12 #include "../slab.h" 13 14 DECLARE_STATIC_KEY_FALSE(kasan_flag_stacktrace); 15 extern bool kasan_flag_async __ro_after_init; 16 17 static inline bool kasan_stack_collection_enabled(void) 18 { 19 return static_branch_unlikely(&kasan_flag_stacktrace); 20 } 21 22 static inline bool kasan_async_mode_enabled(void) 23 { 24 return kasan_flag_async; 25 } 26 #else 27 28 static inline bool kasan_stack_collection_enabled(void) 29 { 30 return true; 31 } 32 33 static inline bool kasan_async_mode_enabled(void) 34 { 35 return false; 36 } 37 38 #endif 39 40 extern bool kasan_flag_panic __ro_after_init; 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 #define KASAN_TAG_KERNEL 0xFF /* native kernel pointers tag */ 55 #define KASAN_TAG_INVALID 0xFE /* inaccessible memory tag */ 56 #define KASAN_TAG_MAX 0xFD /* maximum value for random tags */ 57 58 #ifdef CONFIG_KASAN_HW_TAGS 59 #define KASAN_TAG_MIN 0xF0 /* minimum value for random tags */ 60 #else 61 #define KASAN_TAG_MIN 0x00 /* minimum value for random tags */ 62 #endif 63 64 #ifdef CONFIG_KASAN_GENERIC 65 #define KASAN_FREE_PAGE 0xFF /* page was freed */ 66 #define KASAN_PAGE_REDZONE 0xFE /* redzone for kmalloc_large allocations */ 67 #define KASAN_KMALLOC_REDZONE 0xFC /* redzone inside slub object */ 68 #define KASAN_KMALLOC_FREE 0xFB /* object was freed (kmem_cache_free/kfree) */ 69 #define KASAN_KMALLOC_FREETRACK 0xFA /* object was freed and has free track set */ 70 #else 71 #define KASAN_FREE_PAGE KASAN_TAG_INVALID 72 #define KASAN_PAGE_REDZONE KASAN_TAG_INVALID 73 #define KASAN_KMALLOC_REDZONE KASAN_TAG_INVALID 74 #define KASAN_KMALLOC_FREE KASAN_TAG_INVALID 75 #define KASAN_KMALLOC_FREETRACK KASAN_TAG_INVALID 76 #endif 77 78 #define KASAN_GLOBAL_REDZONE 0xF9 /* redzone for global variable */ 79 #define KASAN_VMALLOC_INVALID 0xF8 /* unallocated space in vmapped page */ 80 81 /* 82 * Stack redzone shadow values 83 * (Those are compiler's ABI, don't change them) 84 */ 85 #define KASAN_STACK_LEFT 0xF1 86 #define KASAN_STACK_MID 0xF2 87 #define KASAN_STACK_RIGHT 0xF3 88 #define KASAN_STACK_PARTIAL 0xF4 89 90 /* 91 * alloca redzone shadow values 92 */ 93 #define KASAN_ALLOCA_LEFT 0xCA 94 #define KASAN_ALLOCA_RIGHT 0xCB 95 96 #define KASAN_ALLOCA_REDZONE_SIZE 32 97 98 /* 99 * Stack frame marker (compiler ABI). 100 */ 101 #define KASAN_CURRENT_STACK_FRAME_MAGIC 0x41B58AB3 102 103 /* Don't break randconfig/all*config builds */ 104 #ifndef KASAN_ABI_VERSION 105 #define KASAN_ABI_VERSION 1 106 #endif 107 108 /* Metadata layout customization. */ 109 #define META_BYTES_PER_BLOCK 1 110 #define META_BLOCKS_PER_ROW 16 111 #define META_BYTES_PER_ROW (META_BLOCKS_PER_ROW * META_BYTES_PER_BLOCK) 112 #define META_MEM_BYTES_PER_ROW (META_BYTES_PER_ROW * KASAN_GRANULE_SIZE) 113 #define META_ROWS_AROUND_ADDR 2 114 115 struct kasan_access_info { 116 const void *access_addr; 117 const void *first_bad_addr; 118 size_t access_size; 119 bool is_write; 120 unsigned long ip; 121 }; 122 123 /* The layout of struct dictated by compiler */ 124 struct kasan_source_location { 125 const char *filename; 126 int line_no; 127 int column_no; 128 }; 129 130 /* The layout of struct dictated by compiler */ 131 struct kasan_global { 132 const void *beg; /* Address of the beginning of the global variable. */ 133 size_t size; /* Size of the global variable. */ 134 size_t size_with_redzone; /* Size of the variable + size of the red zone. 32 bytes aligned */ 135 const void *name; 136 const void *module_name; /* Name of the module where the global variable is declared. */ 137 unsigned long has_dynamic_init; /* This needed for C++ */ 138 #if KASAN_ABI_VERSION >= 4 139 struct kasan_source_location *location; 140 #endif 141 #if KASAN_ABI_VERSION >= 5 142 char *odr_indicator; 143 #endif 144 }; 145 146 /** 147 * Structures to keep alloc and free tracks * 148 */ 149 150 #define KASAN_STACK_DEPTH 64 151 152 struct kasan_track { 153 u32 pid; 154 depot_stack_handle_t stack; 155 }; 156 157 #if defined(CONFIG_KASAN_TAGS_IDENTIFY) && defined(CONFIG_KASAN_SW_TAGS) 158 #define KASAN_NR_FREE_STACKS 5 159 #else 160 #define KASAN_NR_FREE_STACKS 1 161 #endif 162 163 struct kasan_alloc_meta { 164 struct kasan_track alloc_track; 165 #ifdef CONFIG_KASAN_GENERIC 166 /* 167 * The auxiliary stack is stored into struct kasan_alloc_meta. 168 * The free stack is stored into struct kasan_free_meta. 169 */ 170 depot_stack_handle_t aux_stack[2]; 171 #else 172 struct kasan_track free_track[KASAN_NR_FREE_STACKS]; 173 #endif 174 #ifdef CONFIG_KASAN_TAGS_IDENTIFY 175 u8 free_pointer_tag[KASAN_NR_FREE_STACKS]; 176 u8 free_track_idx; 177 #endif 178 }; 179 180 struct qlist_node { 181 struct qlist_node *next; 182 }; 183 184 /* 185 * Generic mode either stores free meta in the object itself or in the redzone 186 * after the object. In the former case free meta offset is 0, in the latter 187 * case it has some sane value smaller than INT_MAX. Use INT_MAX as free meta 188 * offset when free meta isn't present. 189 */ 190 #define KASAN_NO_FREE_META INT_MAX 191 192 struct kasan_free_meta { 193 #ifdef CONFIG_KASAN_GENERIC 194 /* This field is used while the object is in the quarantine. 195 * Otherwise it might be used for the allocator freelist. 196 */ 197 struct qlist_node quarantine_link; 198 struct kasan_track free_track; 199 #endif 200 }; 201 202 struct kasan_alloc_meta *kasan_get_alloc_meta(struct kmem_cache *cache, 203 const void *object); 204 #ifdef CONFIG_KASAN_GENERIC 205 struct kasan_free_meta *kasan_get_free_meta(struct kmem_cache *cache, 206 const void *object); 207 #endif 208 209 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) 210 211 static inline const void *kasan_shadow_to_mem(const void *shadow_addr) 212 { 213 return (void *)(((unsigned long)shadow_addr - KASAN_SHADOW_OFFSET) 214 << KASAN_SHADOW_SCALE_SHIFT); 215 } 216 217 static inline bool addr_has_metadata(const void *addr) 218 { 219 return (addr >= kasan_shadow_to_mem((void *)KASAN_SHADOW_START)); 220 } 221 222 /** 223 * kasan_check_range - Check memory region, and report if invalid access. 224 * @addr: the accessed address 225 * @size: the accessed size 226 * @write: true if access is a write access 227 * @ret_ip: return address 228 * @return: true if access was valid, false if invalid 229 */ 230 bool kasan_check_range(unsigned long addr, size_t size, bool write, 231 unsigned long ret_ip); 232 233 #else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */ 234 235 static inline bool addr_has_metadata(const void *addr) 236 { 237 return (is_vmalloc_addr(addr) || virt_addr_valid(addr)); 238 } 239 240 #endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */ 241 242 #if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS) 243 void kasan_print_tags(u8 addr_tag, const void *addr); 244 #else 245 static inline void kasan_print_tags(u8 addr_tag, const void *addr) { } 246 #endif 247 248 void *kasan_find_first_bad_addr(void *addr, size_t size); 249 const char *kasan_get_bug_type(struct kasan_access_info *info); 250 void kasan_metadata_fetch_row(char *buffer, void *row); 251 252 #if defined(CONFIG_KASAN_GENERIC) && defined(CONFIG_KASAN_STACK) 253 void kasan_print_address_stack_frame(const void *addr); 254 #else 255 static inline void kasan_print_address_stack_frame(const void *addr) { } 256 #endif 257 258 bool kasan_report(unsigned long addr, size_t size, 259 bool is_write, unsigned long ip); 260 void kasan_report_invalid_free(void *object, unsigned long ip); 261 262 struct page *kasan_addr_to_page(const void *addr); 263 264 depot_stack_handle_t kasan_save_stack(gfp_t flags); 265 void kasan_set_track(struct kasan_track *track, gfp_t flags); 266 void kasan_set_free_info(struct kmem_cache *cache, void *object, u8 tag); 267 struct kasan_track *kasan_get_free_track(struct kmem_cache *cache, 268 void *object, u8 tag); 269 270 #if defined(CONFIG_KASAN_GENERIC) && \ 271 (defined(CONFIG_SLAB) || defined(CONFIG_SLUB)) 272 bool kasan_quarantine_put(struct kmem_cache *cache, void *object); 273 void kasan_quarantine_reduce(void); 274 void kasan_quarantine_remove_cache(struct kmem_cache *cache); 275 #else 276 static inline bool kasan_quarantine_put(struct kmem_cache *cache, void *object) { return false; } 277 static inline void kasan_quarantine_reduce(void) { } 278 static inline void kasan_quarantine_remove_cache(struct kmem_cache *cache) { } 279 #endif 280 281 #ifndef arch_kasan_set_tag 282 static inline const void *arch_kasan_set_tag(const void *addr, u8 tag) 283 { 284 return addr; 285 } 286 #endif 287 #ifndef arch_kasan_get_tag 288 #define arch_kasan_get_tag(addr) 0 289 #endif 290 291 #define set_tag(addr, tag) ((void *)arch_kasan_set_tag((addr), (tag))) 292 #define get_tag(addr) arch_kasan_get_tag(addr) 293 294 #ifdef CONFIG_KASAN_HW_TAGS 295 296 #ifndef arch_enable_tagging_sync 297 #define arch_enable_tagging_sync() 298 #endif 299 #ifndef arch_enable_tagging_async 300 #define arch_enable_tagging_async() 301 #endif 302 #ifndef arch_init_tags 303 #define arch_init_tags(max_tag) 304 #endif 305 #ifndef arch_set_tagging_report_once 306 #define arch_set_tagging_report_once(state) 307 #endif 308 #ifndef arch_force_async_tag_fault 309 #define arch_force_async_tag_fault() 310 #endif 311 #ifndef arch_get_random_tag 312 #define arch_get_random_tag() (0xFF) 313 #endif 314 #ifndef arch_get_mem_tag 315 #define arch_get_mem_tag(addr) (0xFF) 316 #endif 317 #ifndef arch_set_mem_tag_range 318 #define arch_set_mem_tag_range(addr, size, tag, init) ((void *)(addr)) 319 #endif 320 321 #define hw_enable_tagging_sync() arch_enable_tagging_sync() 322 #define hw_enable_tagging_async() arch_enable_tagging_async() 323 #define hw_init_tags(max_tag) arch_init_tags(max_tag) 324 #define hw_set_tagging_report_once(state) arch_set_tagging_report_once(state) 325 #define hw_force_async_tag_fault() arch_force_async_tag_fault() 326 #define hw_get_random_tag() arch_get_random_tag() 327 #define hw_get_mem_tag(addr) arch_get_mem_tag(addr) 328 #define hw_set_mem_tag_range(addr, size, tag, init) \ 329 arch_set_mem_tag_range((addr), (size), (tag), (init)) 330 331 #else /* CONFIG_KASAN_HW_TAGS */ 332 333 #define hw_enable_tagging_sync() 334 #define hw_enable_tagging_async() 335 #define hw_set_tagging_report_once(state) 336 337 #endif /* CONFIG_KASAN_HW_TAGS */ 338 339 #if defined(CONFIG_KASAN_HW_TAGS) && IS_ENABLED(CONFIG_KASAN_KUNIT_TEST) 340 341 void kasan_set_tagging_report_once(bool state); 342 void kasan_enable_tagging_sync(void); 343 void kasan_force_async_fault(void); 344 345 #else /* CONFIG_KASAN_HW_TAGS || CONFIG_KASAN_KUNIT_TEST */ 346 347 static inline void kasan_set_tagging_report_once(bool state) { } 348 static inline void kasan_enable_tagging_sync(void) { } 349 static inline void kasan_force_async_fault(void) { } 350 351 #endif /* CONFIG_KASAN_HW_TAGS || CONFIG_KASAN_KUNIT_TEST */ 352 353 #ifdef CONFIG_KASAN_SW_TAGS 354 u8 kasan_random_tag(void); 355 #elif defined(CONFIG_KASAN_HW_TAGS) 356 static inline u8 kasan_random_tag(void) { return hw_get_random_tag(); } 357 #else 358 static inline u8 kasan_random_tag(void) { return 0; } 359 #endif 360 361 #ifdef CONFIG_KASAN_HW_TAGS 362 363 static inline void kasan_poison(const void *addr, size_t size, u8 value, bool init) 364 { 365 addr = kasan_reset_tag(addr); 366 367 /* Skip KFENCE memory if called explicitly outside of sl*b. */ 368 if (is_kfence_address(addr)) 369 return; 370 371 if (WARN_ON((unsigned long)addr & KASAN_GRANULE_MASK)) 372 return; 373 if (WARN_ON(size & KASAN_GRANULE_MASK)) 374 return; 375 376 hw_set_mem_tag_range((void *)addr, size, value, init); 377 } 378 379 static inline void kasan_unpoison(const void *addr, size_t size, bool init) 380 { 381 u8 tag = get_tag(addr); 382 383 addr = kasan_reset_tag(addr); 384 385 /* Skip KFENCE memory if called explicitly outside of sl*b. */ 386 if (is_kfence_address(addr)) 387 return; 388 389 if (WARN_ON((unsigned long)addr & KASAN_GRANULE_MASK)) 390 return; 391 /* 392 * Explicitly initialize the memory with the precise object size to 393 * avoid overwriting the SLAB redzone. This disables initialization in 394 * the arch code and may thus lead to performance penalty. The penalty 395 * is accepted since SLAB redzones aren't enabled in production builds. 396 */ 397 if (__slub_debug_enabled() && 398 init && ((unsigned long)size & KASAN_GRANULE_MASK)) { 399 init = false; 400 memzero_explicit((void *)addr, size); 401 } 402 size = round_up(size, KASAN_GRANULE_SIZE); 403 404 hw_set_mem_tag_range((void *)addr, size, tag, init); 405 } 406 407 static inline bool kasan_byte_accessible(const void *addr) 408 { 409 u8 ptr_tag = get_tag(addr); 410 u8 mem_tag = hw_get_mem_tag((void *)addr); 411 412 return ptr_tag == KASAN_TAG_KERNEL || ptr_tag == mem_tag; 413 } 414 415 #else /* CONFIG_KASAN_HW_TAGS */ 416 417 /** 418 * kasan_poison - mark the memory range as inaccessible 419 * @addr - range start address, must be aligned to KASAN_GRANULE_SIZE 420 * @size - range size, must be aligned to KASAN_GRANULE_SIZE 421 * @value - value that's written to metadata for the range 422 * @init - whether to initialize the memory range (only for hardware tag-based) 423 * 424 * The size gets aligned to KASAN_GRANULE_SIZE before marking the range. 425 */ 426 void kasan_poison(const void *addr, size_t size, u8 value, bool init); 427 428 /** 429 * kasan_unpoison - mark the memory range as accessible 430 * @addr - range start address, must be aligned to KASAN_GRANULE_SIZE 431 * @size - range size, can be unaligned 432 * @init - whether to initialize the memory range (only for hardware tag-based) 433 * 434 * For the tag-based modes, the @size gets aligned to KASAN_GRANULE_SIZE before 435 * marking the range. 436 * For the generic mode, the last granule of the memory range gets partially 437 * unpoisoned based on the @size. 438 */ 439 void kasan_unpoison(const void *addr, size_t size, bool init); 440 441 bool kasan_byte_accessible(const void *addr); 442 443 #endif /* CONFIG_KASAN_HW_TAGS */ 444 445 #ifdef CONFIG_KASAN_GENERIC 446 447 /** 448 * kasan_poison_last_granule - mark the last granule of the memory range as 449 * inaccessible 450 * @addr - range start address, must be aligned to KASAN_GRANULE_SIZE 451 * @size - range size 452 * 453 * This function is only available for the generic mode, as it's the only mode 454 * that has partially poisoned memory granules. 455 */ 456 void kasan_poison_last_granule(const void *address, size_t size); 457 458 #else /* CONFIG_KASAN_GENERIC */ 459 460 static inline void kasan_poison_last_granule(const void *address, size_t size) { } 461 462 #endif /* CONFIG_KASAN_GENERIC */ 463 464 #ifndef kasan_arch_is_ready 465 static inline bool kasan_arch_is_ready(void) { return true; } 466 #elif !defined(CONFIG_KASAN_GENERIC) || !defined(CONFIG_KASAN_OUTLINE) 467 #error kasan_arch_is_ready only works in KASAN generic outline mode! 468 #endif 469 470 /* 471 * Exported functions for interfaces called from assembly or from generated 472 * code. Declarations here to avoid warning about missing declarations. 473 */ 474 asmlinkage void kasan_unpoison_task_stack_below(const void *watermark); 475 void __asan_register_globals(struct kasan_global *globals, size_t size); 476 void __asan_unregister_globals(struct kasan_global *globals, size_t size); 477 void __asan_handle_no_return(void); 478 void __asan_alloca_poison(unsigned long addr, size_t size); 479 void __asan_allocas_unpoison(const void *stack_top, const void *stack_bottom); 480 481 void __asan_load1(unsigned long addr); 482 void __asan_store1(unsigned long addr); 483 void __asan_load2(unsigned long addr); 484 void __asan_store2(unsigned long addr); 485 void __asan_load4(unsigned long addr); 486 void __asan_store4(unsigned long addr); 487 void __asan_load8(unsigned long addr); 488 void __asan_store8(unsigned long addr); 489 void __asan_load16(unsigned long addr); 490 void __asan_store16(unsigned long addr); 491 void __asan_loadN(unsigned long addr, size_t size); 492 void __asan_storeN(unsigned long addr, size_t size); 493 494 void __asan_load1_noabort(unsigned long addr); 495 void __asan_store1_noabort(unsigned long addr); 496 void __asan_load2_noabort(unsigned long addr); 497 void __asan_store2_noabort(unsigned long addr); 498 void __asan_load4_noabort(unsigned long addr); 499 void __asan_store4_noabort(unsigned long addr); 500 void __asan_load8_noabort(unsigned long addr); 501 void __asan_store8_noabort(unsigned long addr); 502 void __asan_load16_noabort(unsigned long addr); 503 void __asan_store16_noabort(unsigned long addr); 504 void __asan_loadN_noabort(unsigned long addr, size_t size); 505 void __asan_storeN_noabort(unsigned long addr, size_t size); 506 507 void __asan_report_load1_noabort(unsigned long addr); 508 void __asan_report_store1_noabort(unsigned long addr); 509 void __asan_report_load2_noabort(unsigned long addr); 510 void __asan_report_store2_noabort(unsigned long addr); 511 void __asan_report_load4_noabort(unsigned long addr); 512 void __asan_report_store4_noabort(unsigned long addr); 513 void __asan_report_load8_noabort(unsigned long addr); 514 void __asan_report_store8_noabort(unsigned long addr); 515 void __asan_report_load16_noabort(unsigned long addr); 516 void __asan_report_store16_noabort(unsigned long addr); 517 void __asan_report_load_n_noabort(unsigned long addr, size_t size); 518 void __asan_report_store_n_noabort(unsigned long addr, size_t size); 519 520 void __asan_set_shadow_00(const void *addr, size_t size); 521 void __asan_set_shadow_f1(const void *addr, size_t size); 522 void __asan_set_shadow_f2(const void *addr, size_t size); 523 void __asan_set_shadow_f3(const void *addr, size_t size); 524 void __asan_set_shadow_f5(const void *addr, size_t size); 525 void __asan_set_shadow_f8(const void *addr, size_t size); 526 527 void __hwasan_load1_noabort(unsigned long addr); 528 void __hwasan_store1_noabort(unsigned long addr); 529 void __hwasan_load2_noabort(unsigned long addr); 530 void __hwasan_store2_noabort(unsigned long addr); 531 void __hwasan_load4_noabort(unsigned long addr); 532 void __hwasan_store4_noabort(unsigned long addr); 533 void __hwasan_load8_noabort(unsigned long addr); 534 void __hwasan_store8_noabort(unsigned long addr); 535 void __hwasan_load16_noabort(unsigned long addr); 536 void __hwasan_store16_noabort(unsigned long addr); 537 void __hwasan_loadN_noabort(unsigned long addr, size_t size); 538 void __hwasan_storeN_noabort(unsigned long addr, size_t size); 539 540 void __hwasan_tag_memory(unsigned long addr, u8 tag, unsigned long size); 541 542 #endif 543