1 //===-- asan_interceptors.cc ------------------------------------*- C++ -*-===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file is a part of AddressSanitizer, an address sanity checker. 11 // 12 // Intercept various libc functions. 13 //===----------------------------------------------------------------------===// 14 #include "asan_interceptors.h" 15 16 #include "asan_allocator.h" 17 #include "asan_interface.h" 18 #include "asan_internal.h" 19 #include "asan_mapping.h" 20 #include "asan_stack.h" 21 #include "asan_stats.h" 22 #include "asan_thread_registry.h" 23 #include "interception/interception.h" 24 25 // Use macro to describe if specific function should be 26 // intercepted on a given platform. 27 #if !defined(_WIN32) 28 # define ASAN_INTERCEPT_ATOLL_AND_STRTOLL 1 29 #else 30 # define ASAN_INTERCEPT_ATOLL_AND_STRTOLL 0 31 #endif 32 33 #if !defined(__APPLE__) 34 # define ASAN_INTERCEPT_STRNLEN 1 35 #else 36 # define ASAN_INTERCEPT_STRNLEN 0 37 #endif 38 39 #if defined(ANDROID) || defined(_WIN32) 40 # define ASAN_INTERCEPT_SIGNAL_AND_SIGACTION 0 41 #else 42 # define ASAN_INTERCEPT_SIGNAL_AND_SIGACTION 1 43 #endif 44 45 // Use extern declarations of intercepted functions on Mac and Windows 46 // to avoid including system headers. 47 #if defined(__APPLE__) || (defined(_WIN32) && !defined(_DLL)) 48 extern "C" { 49 // signal.h 50 # if ASAN_INTERCEPT_SIGNAL_AND_SIGACTION 51 struct sigaction; 52 int sigaction(int sig, const struct sigaction *act, 53 struct sigaction *oldact); 54 void *signal(int signum, void *handler); 55 # endif 56 57 // setjmp.h 58 void longjmp(void* env, int value); 59 # if !defined(_WIN32) 60 void _longjmp(void *env, int value); 61 # endif 62 63 // string.h / strings.h 64 int memcmp(const void *a1, const void *a2, size_t size); 65 void* memmove(void *to, const void *from, size_t size); 66 void* memcpy(void *to, const void *from, size_t size); 67 void* memset(void *block, int c, size_t size); 68 char* strchr(const char *str, int c); 69 # if defined(__APPLE__) 70 char* index(const char *string, int c); 71 # endif 72 char* strcat(char *to, const char* from); // NOLINT 73 char* strcpy(char *to, const char* from); // NOLINT 74 char* strncpy(char *to, const char* from, size_t size); 75 int strcmp(const char *s1, const char* s2); 76 int strncmp(const char *s1, const char* s2, size_t size); 77 # if !defined(_WIN32) 78 int strcasecmp(const char *s1, const char *s2); 79 int strncasecmp(const char *s1, const char *s2, size_t n); 80 char* strdup(const char *s); 81 # endif 82 size_t strlen(const char *s); 83 # if ASAN_INTERCEPT_STRNLEN 84 size_t strnlen(const char *s, size_t maxlen); 85 # endif 86 87 // stdlib.h 88 int atoi(const char *nptr); 89 long atol(const char *nptr); // NOLINT 90 long strtol(const char *nptr, char **endptr, int base); // NOLINT 91 # if ASAN_INTERCEPT_ATOLL_AND_STRTOLL 92 long long atoll(const char *nptr); // NOLINT 93 long long strtoll(const char *nptr, char **endptr, int base); // NOLINT 94 # endif 95 96 // Windows threads. 97 # if defined(_WIN32) 98 __declspec(dllimport) 99 void* __stdcall CreateThread(void *sec, size_t st, void* start, 100 void *arg, DWORD fl, DWORD *id); 101 # endif 102 103 // Posix threads. 104 # if !defined(_WIN32) 105 int pthread_create(void *thread, void *attr, void *(*start_routine)(void*), 106 void *arg); 107 # endif 108 } // extern "C" 109 #endif 110 111 namespace __asan { 112 113 // Instruments read/write access to a single byte in memory. 114 // On error calls __asan_report_error, which aborts the program. 115 #define ACCESS_ADDRESS(address, isWrite) do { \ 116 if (AddressIsPoisoned(address)) { \ 117 GET_CURRENT_PC_BP_SP; \ 118 __asan_report_error(pc, bp, sp, address, isWrite, /* access_size */ 1); \ 119 } \ 120 } while (0) 121 122 // We implement ACCESS_MEMORY_RANGE, ASAN_READ_RANGE, 123 // and ASAN_WRITE_RANGE as macro instead of function so 124 // that no extra frames are created, and stack trace contains 125 // relevant information only. 126 127 // Instruments read/write access to a memory range. 128 // More complex implementation is possible, for now just 129 // checking the first and the last byte of a range. 130 #define ACCESS_MEMORY_RANGE(offset, size, isWrite) do { \ 131 if (size > 0) { \ 132 uintptr_t ptr = (uintptr_t)(offset); \ 133 ACCESS_ADDRESS(ptr, isWrite); \ 134 ACCESS_ADDRESS(ptr + (size) - 1, isWrite); \ 135 } \ 136 } while (0) 137 138 #define ASAN_READ_RANGE(offset, size) do { \ 139 ACCESS_MEMORY_RANGE(offset, size, false); \ 140 } while (0) 141 142 #define ASAN_WRITE_RANGE(offset, size) do { \ 143 ACCESS_MEMORY_RANGE(offset, size, true); \ 144 } while (0) 145 146 // Behavior of functions like "memcpy" or "strcpy" is undefined 147 // if memory intervals overlap. We report error in this case. 148 // Macro is used to avoid creation of new frames. 149 static inline bool RangesOverlap(const char *offset1, size_t length1, 150 const char *offset2, size_t length2) { 151 return !((offset1 + length1 <= offset2) || (offset2 + length2 <= offset1)); 152 } 153 #define CHECK_RANGES_OVERLAP(name, _offset1, length1, _offset2, length2) do { \ 154 const char *offset1 = (const char*)_offset1; \ 155 const char *offset2 = (const char*)_offset2; \ 156 if (RangesOverlap(offset1, length1, offset2, length2)) { \ 157 Report("ERROR: AddressSanitizer %s-param-overlap: " \ 158 "memory ranges [%p,%p) and [%p, %p) overlap\n", \ 159 name, offset1, offset1 + length1, offset2, offset2 + length2); \ 160 PRINT_CURRENT_STACK(); \ 161 ShowStatsAndAbort(); \ 162 } \ 163 } while (0) 164 165 #define ENSURE_ASAN_INITED() do { \ 166 CHECK(!asan_init_is_running); \ 167 if (!asan_inited) { \ 168 __asan_init(); \ 169 } \ 170 } while (0) 171 172 static inline bool IsSpace(int c) { 173 return (c == ' ') || (c == '\n') || (c == '\t') || 174 (c == '\f') || (c == '\r') || (c == '\v'); 175 } 176 177 static inline bool IsDigit(int c) { 178 return (c >= '0') && (c <= '9'); 179 } 180 181 static inline int ToLower(int c) { 182 return (c >= 'A' && c <= 'Z') ? (c + 'a' - 'A') : c; 183 } 184 185 // ---------------------- Internal string functions ---------------- {{{1 186 187 int64_t internal_simple_strtoll(const char *nptr, char **endptr, int base) { 188 CHECK(base == 10); 189 while (IsSpace(*nptr)) nptr++; 190 int sgn = 1; 191 uint64_t res = 0; 192 bool have_digits = false; 193 char *old_nptr = (char*)nptr; 194 if (*nptr == '+') { 195 sgn = 1; 196 nptr++; 197 } else if (*nptr == '-') { 198 sgn = -1; 199 nptr++; 200 } 201 while (IsDigit(*nptr)) { 202 res = (res <= UINT64_MAX / 10) ? res * 10 : UINT64_MAX; 203 int digit = ((*nptr) - '0'); 204 res = (res <= UINT64_MAX - digit) ? res + digit : UINT64_MAX; 205 have_digits = true; 206 nptr++; 207 } 208 if (endptr != NULL) { 209 *endptr = (have_digits) ? (char*)nptr : old_nptr; 210 } 211 if (sgn > 0) { 212 return (int64_t)(Min((uint64_t)INT64_MAX, res)); 213 } else { 214 return (res > INT64_MAX) ? INT64_MIN : ((int64_t)res * -1); 215 } 216 } 217 218 int64_t internal_atoll(const char *nptr) { 219 return internal_simple_strtoll(nptr, (char**)NULL, 10); 220 } 221 222 size_t internal_strlen(const char *s) { 223 size_t i = 0; 224 while (s[i]) i++; 225 return i; 226 } 227 228 size_t internal_strnlen(const char *s, size_t maxlen) { 229 #if ASAN_INTERCEPT_STRNLEN 230 if (REAL(strnlen) != NULL) { 231 return REAL(strnlen)(s, maxlen); 232 } 233 #endif 234 size_t i = 0; 235 while (i < maxlen && s[i]) i++; 236 return i; 237 } 238 239 char* internal_strchr(const char *s, int c) { 240 while (true) { 241 if (*s == (char)c) 242 return (char*)s; 243 if (*s == 0) 244 return NULL; 245 s++; 246 } 247 } 248 249 void* internal_memchr(const void* s, int c, size_t n) { 250 const char* t = (char*)s; 251 for (size_t i = 0; i < n; ++i, ++t) 252 if (*t == c) 253 return (void*)t; 254 return NULL; 255 } 256 257 int internal_memcmp(const void* s1, const void* s2, size_t n) { 258 const char* t1 = (char*)s1; 259 const char* t2 = (char*)s2; 260 for (size_t i = 0; i < n; ++i, ++t1, ++t2) 261 if (*t1 != *t2) 262 return *t1 < *t2 ? -1 : 1; 263 return 0; 264 } 265 266 // Should not be used in performance-critical places. 267 void* internal_memset(void* s, int c, size_t n) { 268 // The next line prevents Clang from making a call to memset() instead of the 269 // loop below. 270 // FIXME: building the runtime with -ffreestanding is a better idea. However 271 // there currently are linktime problems due to PR12396. 272 char volatile *t = (char*)s; 273 for (size_t i = 0; i < n; ++i, ++t) { 274 *t = c; 275 } 276 return s; 277 } 278 279 char *internal_strstr(const char *haystack, const char *needle) { 280 // This is O(N^2), but we are not using it in hot places. 281 size_t len1 = internal_strlen(haystack); 282 size_t len2 = internal_strlen(needle); 283 if (len1 < len2) return 0; 284 for (size_t pos = 0; pos <= len1 - len2; pos++) { 285 if (internal_memcmp(haystack + pos, needle, len2) == 0) 286 return (char*)haystack + pos; 287 } 288 return 0; 289 } 290 291 char *internal_strncat(char *dst, const char *src, size_t n) { 292 size_t len = internal_strlen(dst); 293 size_t i; 294 for (i = 0; i < n && src[i]; i++) 295 dst[len + i] = src[i]; 296 dst[len + i] = 0; 297 return dst; 298 } 299 300 int internal_strcmp(const char *s1, const char *s2) { 301 while (true) { 302 unsigned c1 = *s1; 303 unsigned c2 = *s2; 304 if (c1 != c2) return (c1 < c2) ? -1 : 1; 305 if (c1 == 0) break; 306 s1++; 307 s2++; 308 } 309 return 0; 310 } 311 312 char *internal_strncpy(char *dst, const char *src, size_t n) { 313 size_t i; 314 for (i = 0; i < n && src[i]; i++) 315 dst[i] = src[i]; 316 return dst; 317 } 318 319 } // namespace __asan 320 321 // ---------------------- Wrappers ---------------- {{{1 322 using namespace __asan; // NOLINT 323 324 static thread_return_t THREAD_CALLING_CONV asan_thread_start(void *arg) { 325 AsanThread *t = (AsanThread*)arg; 326 asanThreadRegistry().SetCurrent(t); 327 return t->ThreadStart(); 328 } 329 330 #ifndef _WIN32 331 INTERCEPTOR(int, pthread_create, void *thread, 332 void *attr, void *(*start_routine)(void*), void *arg) { 333 GET_STACK_TRACE_HERE(kStackTraceMax); 334 int current_tid = asanThreadRegistry().GetCurrentTidOrMinusOne(); 335 AsanThread *t = AsanThread::Create(current_tid, start_routine, arg, &stack); 336 asanThreadRegistry().RegisterThread(t); 337 return REAL(pthread_create)(thread, attr, asan_thread_start, t); 338 } 339 #endif // !_WIN32 340 341 #if ASAN_INTERCEPT_SIGNAL_AND_SIGACTION 342 INTERCEPTOR(void*, signal, int signum, void *handler) { 343 if (!AsanInterceptsSignal(signum)) { 344 return REAL(signal)(signum, handler); 345 } 346 return NULL; 347 } 348 349 INTERCEPTOR(int, sigaction, int signum, const struct sigaction *act, 350 struct sigaction *oldact) { 351 if (!AsanInterceptsSignal(signum)) { 352 return REAL(sigaction)(signum, act, oldact); 353 } 354 return 0; 355 } 356 #elif ASAN_POSIX 357 // We need to have defined REAL(sigaction) on posix systems. 358 DEFINE_REAL(int, sigaction, int signum, const struct sigaction *act, 359 struct sigaction *oldact); 360 #endif // ASAN_INTERCEPT_SIGNAL_AND_SIGACTION 361 362 INTERCEPTOR(void, longjmp, void *env, int val) { 363 __asan_handle_no_return(); 364 REAL(longjmp)(env, val); 365 } 366 367 #if !defined(_WIN32) 368 INTERCEPTOR(void, _longjmp, void *env, int val) { 369 __asan_handle_no_return(); 370 REAL(_longjmp)(env, val); 371 } 372 373 INTERCEPTOR(void, siglongjmp, void *env, int val) { 374 __asan_handle_no_return(); 375 REAL(siglongjmp)(env, val); 376 } 377 #endif 378 379 #if ASAN_HAS_EXCEPTIONS == 1 380 #ifdef __APPLE__ 381 extern "C" void __cxa_throw(void *a, void *b, void *c); 382 #endif // __APPLE__ 383 384 INTERCEPTOR(void, __cxa_throw, void *a, void *b, void *c) { 385 CHECK(REAL(__cxa_throw)); 386 __asan_handle_no_return(); 387 REAL(__cxa_throw)(a, b, c); 388 } 389 #endif 390 391 // intercept mlock and friends. 392 // Since asan maps 16T of RAM, mlock is completely unfriendly to asan. 393 // All functions return 0 (success). 394 static void MlockIsUnsupported() { 395 static bool printed = 0; 396 if (printed) return; 397 printed = true; 398 Printf("INFO: AddressSanitizer ignores mlock/mlockall/munlock/munlockall\n"); 399 } 400 401 extern "C" { 402 INTERCEPTOR_ATTRIBUTE 403 int mlock(const void *addr, size_t len) { 404 MlockIsUnsupported(); 405 return 0; 406 } 407 408 INTERCEPTOR_ATTRIBUTE 409 int munlock(const void *addr, size_t len) { 410 MlockIsUnsupported(); 411 return 0; 412 } 413 414 INTERCEPTOR_ATTRIBUTE 415 int mlockall(int flags) { 416 MlockIsUnsupported(); 417 return 0; 418 } 419 420 INTERCEPTOR_ATTRIBUTE 421 int munlockall(void) { 422 MlockIsUnsupported(); 423 return 0; 424 } 425 } // extern "C" 426 427 static inline int CharCmp(unsigned char c1, unsigned char c2) { 428 return (c1 == c2) ? 0 : (c1 < c2) ? -1 : 1; 429 } 430 431 static inline int CharCaseCmp(unsigned char c1, unsigned char c2) { 432 int c1_low = ToLower(c1); 433 int c2_low = ToLower(c2); 434 return c1_low - c2_low; 435 } 436 437 INTERCEPTOR(int, memcmp, const void *a1, const void *a2, size_t size) { 438 ENSURE_ASAN_INITED(); 439 unsigned char c1 = 0, c2 = 0; 440 const unsigned char *s1 = (const unsigned char*)a1; 441 const unsigned char *s2 = (const unsigned char*)a2; 442 size_t i; 443 for (i = 0; i < size; i++) { 444 c1 = s1[i]; 445 c2 = s2[i]; 446 if (c1 != c2) break; 447 } 448 ASAN_READ_RANGE(s1, Min(i + 1, size)); 449 ASAN_READ_RANGE(s2, Min(i + 1, size)); 450 return CharCmp(c1, c2); 451 } 452 453 INTERCEPTOR(void*, memcpy, void *to, const void *from, size_t size) { 454 // memcpy is called during __asan_init() from the internals 455 // of printf(...). 456 if (asan_init_is_running) { 457 return REAL(memcpy)(to, from, size); 458 } 459 ENSURE_ASAN_INITED(); 460 if (FLAG_replace_intrin) { 461 if (to != from) { 462 // We do not treat memcpy with to==from as a bug. 463 // See http://llvm.org/bugs/show_bug.cgi?id=11763. 464 CHECK_RANGES_OVERLAP("memcpy", to, size, from, size); 465 } 466 ASAN_WRITE_RANGE(from, size); 467 ASAN_READ_RANGE(to, size); 468 } 469 return REAL(memcpy)(to, from, size); 470 } 471 472 INTERCEPTOR(void*, memmove, void *to, const void *from, size_t size) { 473 ENSURE_ASAN_INITED(); 474 if (FLAG_replace_intrin) { 475 ASAN_WRITE_RANGE(from, size); 476 ASAN_READ_RANGE(to, size); 477 } 478 return REAL(memmove)(to, from, size); 479 } 480 481 INTERCEPTOR(void*, memset, void *block, int c, size_t size) { 482 // memset is called inside Printf. 483 if (asan_init_is_running) { 484 return REAL(memset)(block, c, size); 485 } 486 ENSURE_ASAN_INITED(); 487 if (FLAG_replace_intrin) { 488 ASAN_WRITE_RANGE(block, size); 489 } 490 return REAL(memset)(block, c, size); 491 } 492 493 INTERCEPTOR(char*, strchr, const char *str, int c) { 494 ENSURE_ASAN_INITED(); 495 char *result = REAL(strchr)(str, c); 496 if (FLAG_replace_str) { 497 size_t bytes_read = (result ? result - str : REAL(strlen)(str)) + 1; 498 ASAN_READ_RANGE(str, bytes_read); 499 } 500 return result; 501 } 502 503 #ifdef __linux__ 504 INTERCEPTOR(char*, index, const char *string, int c) 505 ALIAS(WRAPPER_NAME(strchr)); 506 #else 507 DEFINE_REAL(char*, index, const char *string, int c); 508 #endif 509 510 INTERCEPTOR(int, strcasecmp, const char *s1, const char *s2) { 511 ENSURE_ASAN_INITED(); 512 unsigned char c1, c2; 513 size_t i; 514 for (i = 0; ; i++) { 515 c1 = (unsigned char)s1[i]; 516 c2 = (unsigned char)s2[i]; 517 if (CharCaseCmp(c1, c2) != 0 || c1 == '\0') break; 518 } 519 ASAN_READ_RANGE(s1, i + 1); 520 ASAN_READ_RANGE(s2, i + 1); 521 return CharCaseCmp(c1, c2); 522 } 523 524 INTERCEPTOR(char*, strcat, char *to, const char *from) { // NOLINT 525 ENSURE_ASAN_INITED(); 526 if (FLAG_replace_str) { 527 size_t from_length = REAL(strlen)(from); 528 ASAN_READ_RANGE(from, from_length + 1); 529 if (from_length > 0) { 530 size_t to_length = REAL(strlen)(to); 531 ASAN_READ_RANGE(to, to_length); 532 ASAN_WRITE_RANGE(to + to_length, from_length + 1); 533 CHECK_RANGES_OVERLAP("strcat", to, to_length + 1, from, from_length + 1); 534 } 535 } 536 return REAL(strcat)(to, from); // NOLINT 537 } 538 539 INTERCEPTOR(int, strcmp, const char *s1, const char *s2) { 540 if (!asan_inited) { 541 return internal_strcmp(s1, s2); 542 } 543 unsigned char c1, c2; 544 size_t i; 545 for (i = 0; ; i++) { 546 c1 = (unsigned char)s1[i]; 547 c2 = (unsigned char)s2[i]; 548 if (c1 != c2 || c1 == '\0') break; 549 } 550 ASAN_READ_RANGE(s1, i + 1); 551 ASAN_READ_RANGE(s2, i + 1); 552 return CharCmp(c1, c2); 553 } 554 555 INTERCEPTOR(char*, strcpy, char *to, const char *from) { // NOLINT 556 // strcpy is called from malloc_default_purgeable_zone() 557 // in __asan::ReplaceSystemAlloc() on Mac. 558 if (asan_init_is_running) { 559 return REAL(strcpy)(to, from); // NOLINT 560 } 561 ENSURE_ASAN_INITED(); 562 if (FLAG_replace_str) { 563 size_t from_size = REAL(strlen)(from) + 1; 564 CHECK_RANGES_OVERLAP("strcpy", to, from_size, from, from_size); 565 ASAN_READ_RANGE(from, from_size); 566 ASAN_WRITE_RANGE(to, from_size); 567 } 568 return REAL(strcpy)(to, from); // NOLINT 569 } 570 571 INTERCEPTOR(char*, strdup, const char *s) { 572 ENSURE_ASAN_INITED(); 573 if (FLAG_replace_str) { 574 size_t length = REAL(strlen)(s); 575 ASAN_READ_RANGE(s, length + 1); 576 } 577 return REAL(strdup)(s); 578 } 579 580 INTERCEPTOR(size_t, strlen, const char *s) { 581 // strlen is called from malloc_default_purgeable_zone() 582 // in __asan::ReplaceSystemAlloc() on Mac. 583 if (asan_init_is_running) { 584 return REAL(strlen)(s); 585 } 586 ENSURE_ASAN_INITED(); 587 size_t length = REAL(strlen)(s); 588 if (FLAG_replace_str) { 589 ASAN_READ_RANGE(s, length + 1); 590 } 591 return length; 592 } 593 594 INTERCEPTOR(int, strncasecmp, const char *s1, const char *s2, size_t n) { 595 ENSURE_ASAN_INITED(); 596 unsigned char c1 = 0, c2 = 0; 597 size_t i; 598 for (i = 0; i < n; i++) { 599 c1 = (unsigned char)s1[i]; 600 c2 = (unsigned char)s2[i]; 601 if (CharCaseCmp(c1, c2) != 0 || c1 == '\0') break; 602 } 603 ASAN_READ_RANGE(s1, Min(i + 1, n)); 604 ASAN_READ_RANGE(s2, Min(i + 1, n)); 605 return CharCaseCmp(c1, c2); 606 } 607 608 INTERCEPTOR(int, strncmp, const char *s1, const char *s2, size_t size) { 609 // strncmp is called from malloc_default_purgeable_zone() 610 // in __asan::ReplaceSystemAlloc() on Mac. 611 if (asan_init_is_running) { 612 return REAL(strncmp)(s1, s2, size); 613 } 614 unsigned char c1 = 0, c2 = 0; 615 size_t i; 616 for (i = 0; i < size; i++) { 617 c1 = (unsigned char)s1[i]; 618 c2 = (unsigned char)s2[i]; 619 if (c1 != c2 || c1 == '\0') break; 620 } 621 ASAN_READ_RANGE(s1, Min(i + 1, size)); 622 ASAN_READ_RANGE(s2, Min(i + 1, size)); 623 return CharCmp(c1, c2); 624 } 625 626 INTERCEPTOR(char*, strncpy, char *to, const char *from, size_t size) { 627 ENSURE_ASAN_INITED(); 628 if (FLAG_replace_str) { 629 size_t from_size = Min(size, internal_strnlen(from, size) + 1); 630 CHECK_RANGES_OVERLAP("strncpy", to, from_size, from, from_size); 631 ASAN_READ_RANGE(from, from_size); 632 ASAN_WRITE_RANGE(to, size); 633 } 634 return REAL(strncpy)(to, from, size); 635 } 636 637 #if ASAN_INTERCEPT_STRNLEN 638 INTERCEPTOR(size_t, strnlen, const char *s, size_t maxlen) { 639 ENSURE_ASAN_INITED(); 640 size_t length = REAL(strnlen)(s, maxlen); 641 if (FLAG_replace_str) { 642 ASAN_READ_RANGE(s, Min(length + 1, maxlen)); 643 } 644 return length; 645 } 646 #endif // ASAN_INTERCEPT_STRNLEN 647 648 static inline bool IsValidStrtolBase(int base) { 649 return (base == 0) || (2 <= base && base <= 36); 650 } 651 652 static inline void FixRealStrtolEndptr(const char *nptr, char **endptr) { 653 CHECK(endptr != NULL); 654 if (nptr == *endptr) { 655 // No digits were found at strtol call, we need to find out the last 656 // symbol accessed by strtoll on our own. 657 // We get this symbol by skipping leading blanks and optional +/- sign. 658 while (IsSpace(*nptr)) nptr++; 659 if (*nptr == '+' || *nptr == '-') nptr++; 660 *endptr = (char*)nptr; 661 } 662 CHECK(*endptr >= nptr); 663 } 664 665 INTERCEPTOR(long, strtol, const char *nptr, // NOLINT 666 char **endptr, int base) { 667 ENSURE_ASAN_INITED(); 668 if (!FLAG_replace_str) { 669 return REAL(strtol)(nptr, endptr, base); 670 } 671 char *real_endptr; 672 long result = REAL(strtol)(nptr, &real_endptr, base); // NOLINT 673 if (endptr != NULL) { 674 *endptr = real_endptr; 675 } 676 if (IsValidStrtolBase(base)) { 677 FixRealStrtolEndptr(nptr, &real_endptr); 678 ASAN_READ_RANGE(nptr, (real_endptr - nptr) + 1); 679 } 680 return result; 681 } 682 683 INTERCEPTOR(int, atoi, const char *nptr) { 684 ENSURE_ASAN_INITED(); 685 if (!FLAG_replace_str) { 686 return REAL(atoi)(nptr); 687 } 688 char *real_endptr; 689 // "man atoi" tells that behavior of atoi(nptr) is the same as 690 // strtol(nptr, NULL, 10), i.e. it sets errno to ERANGE if the 691 // parsed integer can't be stored in *long* type (even if it's 692 // different from int). So, we just imitate this behavior. 693 int result = REAL(strtol)(nptr, &real_endptr, 10); 694 FixRealStrtolEndptr(nptr, &real_endptr); 695 ASAN_READ_RANGE(nptr, (real_endptr - nptr) + 1); 696 return result; 697 } 698 699 INTERCEPTOR(long, atol, const char *nptr) { // NOLINT 700 ENSURE_ASAN_INITED(); 701 if (!FLAG_replace_str) { 702 return REAL(atol)(nptr); 703 } 704 char *real_endptr; 705 long result = REAL(strtol)(nptr, &real_endptr, 10); // NOLINT 706 FixRealStrtolEndptr(nptr, &real_endptr); 707 ASAN_READ_RANGE(nptr, (real_endptr - nptr) + 1); 708 return result; 709 } 710 711 #if ASAN_INTERCEPT_ATOLL_AND_STRTOLL 712 INTERCEPTOR(long long, strtoll, const char *nptr, // NOLINT 713 char **endptr, int base) { 714 ENSURE_ASAN_INITED(); 715 if (!FLAG_replace_str) { 716 return REAL(strtoll)(nptr, endptr, base); 717 } 718 char *real_endptr; 719 long long result = REAL(strtoll)(nptr, &real_endptr, base); // NOLINT 720 if (endptr != NULL) { 721 *endptr = real_endptr; 722 } 723 // If base has unsupported value, strtoll can exit with EINVAL 724 // without reading any characters. So do additional checks only 725 // if base is valid. 726 if (IsValidStrtolBase(base)) { 727 FixRealStrtolEndptr(nptr, &real_endptr); 728 ASAN_READ_RANGE(nptr, (real_endptr - nptr) + 1); 729 } 730 return result; 731 } 732 733 INTERCEPTOR(long long, atoll, const char *nptr) { // NOLINT 734 ENSURE_ASAN_INITED(); 735 if (!FLAG_replace_str) { 736 return REAL(atoll)(nptr); 737 } 738 char *real_endptr; 739 long long result = REAL(strtoll)(nptr, &real_endptr, 10); // NOLINT 740 FixRealStrtolEndptr(nptr, &real_endptr); 741 ASAN_READ_RANGE(nptr, (real_endptr - nptr) + 1); 742 return result; 743 } 744 #endif // ASAN_INTERCEPT_ATOLL_AND_STRTOLL 745 746 #if defined(_WIN32) 747 INTERCEPTOR_WINAPI(DWORD, CreateThread, 748 void* security, size_t stack_size, 749 DWORD (__stdcall *start_routine)(void*), void* arg, 750 DWORD flags, void* tid) { 751 GET_STACK_TRACE_HERE(kStackTraceMax); 752 int current_tid = asanThreadRegistry().GetCurrentTidOrMinusOne(); 753 AsanThread *t = AsanThread::Create(current_tid, start_routine, arg, &stack); 754 asanThreadRegistry().RegisterThread(t); 755 return REAL(CreateThread)(security, stack_size, 756 asan_thread_start, t, flags, tid); 757 } 758 759 namespace __asan { 760 void InitializeWindowsInterceptors() { 761 CHECK(INTERCEPT_FUNCTION(CreateThread)); 762 } 763 764 } // namespace __asan 765 #endif 766 767 // ---------------------- InitializeAsanInterceptors ---------------- {{{1 768 namespace __asan { 769 void InitializeAsanInterceptors() { 770 static bool was_called_once; 771 CHECK(was_called_once == false); 772 was_called_once = true; 773 // Intercept mem* functions. 774 CHECK(INTERCEPT_FUNCTION(memcmp)); 775 CHECK(INTERCEPT_FUNCTION(memmove)); 776 CHECK(INTERCEPT_FUNCTION(memset)); 777 if (PLATFORM_HAS_DIFFERENT_MEMCPY_AND_MEMMOVE) { 778 CHECK(INTERCEPT_FUNCTION(memcpy)); 779 } else { 780 REAL(memcpy) = REAL(memmove); 781 } 782 783 // Intercept str* functions. 784 CHECK(INTERCEPT_FUNCTION(strcat)); // NOLINT 785 CHECK(INTERCEPT_FUNCTION(strchr)); 786 CHECK(INTERCEPT_FUNCTION(strcmp)); 787 CHECK(INTERCEPT_FUNCTION(strcpy)); // NOLINT 788 CHECK(INTERCEPT_FUNCTION(strlen)); 789 CHECK(INTERCEPT_FUNCTION(strncmp)); 790 CHECK(INTERCEPT_FUNCTION(strncpy)); 791 #if !defined(_WIN32) 792 CHECK(INTERCEPT_FUNCTION(strcasecmp)); 793 CHECK(INTERCEPT_FUNCTION(strdup)); 794 CHECK(INTERCEPT_FUNCTION(strncasecmp)); 795 # ifndef __APPLE__ 796 CHECK(INTERCEPT_FUNCTION(index)); 797 # else 798 CHECK(OVERRIDE_FUNCTION(index, WRAP(strchr))); 799 # endif 800 #endif 801 #if ASAN_INTERCEPT_STRNLEN 802 CHECK(INTERCEPT_FUNCTION(strnlen)); 803 #endif 804 805 CHECK(INTERCEPT_FUNCTION(atoi)); 806 CHECK(INTERCEPT_FUNCTION(atol)); 807 CHECK(INTERCEPT_FUNCTION(strtol)); 808 #if ASAN_INTERCEPT_ATOLL_AND_STRTOLL 809 CHECK(INTERCEPT_FUNCTION(atoll)); 810 CHECK(INTERCEPT_FUNCTION(strtoll)); 811 #endif 812 813 // Intecept signal- and jump-related functions. 814 CHECK(INTERCEPT_FUNCTION(longjmp)); 815 #if ASAN_INTERCEPT_SIGNAL_AND_SIGACTION 816 CHECK(INTERCEPT_FUNCTION(sigaction)); 817 CHECK(INTERCEPT_FUNCTION(signal)); 818 #endif 819 820 #if !defined(_WIN32) 821 CHECK(INTERCEPT_FUNCTION(_longjmp)); 822 INTERCEPT_FUNCTION(__cxa_throw); 823 # if !defined(__APPLE__) 824 // On Darwin siglongjmp tailcalls longjmp, so we don't want to intercept it 825 // there. 826 CHECK(INTERCEPT_FUNCTION(siglongjmp)); 827 # endif 828 #endif 829 830 // Intercept threading-related functions 831 #if !defined(_WIN32) 832 CHECK(INTERCEPT_FUNCTION(pthread_create)); 833 #endif 834 835 // Some Windows-specific interceptors. 836 #if defined(_WIN32) 837 InitializeWindowsInterceptors(); 838 #endif 839 840 // Some Mac-specific interceptors. 841 #if defined(__APPLE__) 842 InitializeMacInterceptors(); 843 #endif 844 845 if (FLAG_v > 0) { 846 Report("AddressSanitizer: libc interceptors initialized\n"); 847 } 848 } 849 850 } // namespace __asan 851
