asan_rtl.cc revision d6567c5166412f6acdde851e767c26f332d51d3d
1//===-- asan_rtl.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// Main file of the ASan run-time library. 13//===----------------------------------------------------------------------===// 14#include "asan_allocator.h" 15#include "asan_interceptors.h" 16#include "asan_interface.h" 17#include "asan_internal.h" 18#include "asan_lock.h" 19#ifdef __APPLE__ 20#include "asan_mac.h" 21#endif 22#include "asan_mapping.h" 23#include "asan_stack.h" 24#include "asan_stats.h" 25#include "asan_thread.h" 26#include "asan_thread_registry.h" 27 28#include <algorithm> 29#include <map> 30#include <dlfcn.h> 31#include <execinfo.h> 32#include <fcntl.h> 33#include <pthread.h> 34#include <signal.h> 35#include <stdarg.h> 36#include <stdint.h> 37#include <stdio.h> 38#include <stdlib.h> 39#include <string.h> 40#include <sys/mman.h> 41#include <sys/stat.h> 42#include <sys/types.h> 43#include <sys/ucontext.h> 44#include <sys/time.h> 45#include <sys/resource.h> 46#include <unistd.h> 47// must not include <setjmp.h> on Linux 48 49#ifndef ASAN_NEEDS_SEGV 50# define ASAN_NEEDS_SEGV 1 51#endif 52 53namespace __asan { 54 55// -------------------------- Flags ------------------------- {{{1 56static const size_t kMallocContextSize = 30; 57static int FLAG_atexit; 58bool FLAG_fast_unwind = true; 59 60size_t FLAG_redzone; // power of two, >= 32 61bool FLAG_mt; // set to 0 if you have only one thread. 62size_t FLAG_quarantine_size; 63int FLAG_demangle; 64bool FLAG_symbolize; 65int FLAG_v; 66int FLAG_debug; 67bool FLAG_poison_shadow; 68int FLAG_report_globals; 69size_t FLAG_malloc_context_size = kMallocContextSize; 70uintptr_t FLAG_large_malloc; 71bool FLAG_lazy_shadow; 72bool FLAG_handle_segv; 73bool FLAG_handle_sigill; 74bool FLAG_replace_str; 75bool FLAG_replace_intrin; 76bool FLAG_replace_cfallocator; // Used on Mac only. 77bool FLAG_stats; 78size_t FLAG_max_malloc_fill_size = 0; 79bool FLAG_use_fake_stack; 80int FLAG_exitcode = EXIT_FAILURE; 81bool FLAG_allow_user_poisoning; 82 83// -------------------------- Globals --------------------- {{{1 84int asan_inited; 85bool asan_init_is_running; 86 87// -------------------------- Interceptors ---------------- {{{1 88typedef int (*sigaction_f)(int signum, const struct sigaction *act, 89 struct sigaction *oldact); 90typedef sig_t (*signal_f)(int signum, sig_t handler); 91typedef void (*longjmp_f)(void *env, int val); 92typedef longjmp_f _longjmp_f; 93typedef longjmp_f siglongjmp_f; 94typedef void (*__cxa_throw_f)(void *, void *, void *); 95typedef int (*pthread_create_f)(pthread_t *thread, const pthread_attr_t *attr, 96 void *(*start_routine) (void *), void *arg); 97#ifdef __APPLE__ 98dispatch_async_f_f real_dispatch_async_f; 99dispatch_sync_f_f real_dispatch_sync_f; 100dispatch_after_f_f real_dispatch_after_f; 101dispatch_barrier_async_f_f real_dispatch_barrier_async_f; 102dispatch_group_async_f_f real_dispatch_group_async_f; 103pthread_workqueue_additem_np_f real_pthread_workqueue_additem_np; 104#endif 105 106sigaction_f real_sigaction; 107signal_f real_signal; 108longjmp_f real_longjmp; 109_longjmp_f real__longjmp; 110siglongjmp_f real_siglongjmp; 111__cxa_throw_f real___cxa_throw; 112pthread_create_f real_pthread_create; 113 114// -------------------------- Misc ---------------- {{{1 115void ShowStatsAndAbort() { 116 __asan_print_accumulated_stats(); 117 ASAN_DIE; 118} 119 120static void PrintBytes(const char *before, uintptr_t *a) { 121 uint8_t *bytes = (uint8_t*)a; 122 size_t byte_num = (__WORDSIZE) / 8; 123 Printf("%s%p:", before, (uintptr_t)a); 124 for (size_t i = 0; i < byte_num; i++) { 125 Printf(" %lx%lx", bytes[i] >> 4, bytes[i] & 15); 126 } 127 Printf("\n"); 128} 129 130// ---------------------- Thread ------------------------- {{{1 131static void *asan_thread_start(void *arg) { 132 AsanThread *t= (AsanThread*)arg; 133 asanThreadRegistry().SetCurrent(t); 134 return t->ThreadStart(); 135} 136 137// ---------------------- mmap -------------------- {{{1 138static void OutOfMemoryMessage(const char *mem_type, size_t size) { 139 Report("ERROR: AddressSanitizer failed to allocate " 140 "0x%lx (%ld) bytes of %s\n", 141 size, size, mem_type); 142} 143 144static char *mmap_pages(size_t start_page, size_t n_pages, const char *mem_type, 145 bool abort_on_failure = true) { 146 void *res = asan_mmap((void*)start_page, kPageSize * n_pages, 147 PROT_READ | PROT_WRITE, 148 MAP_PRIVATE | MAP_ANON | MAP_FIXED | MAP_NORESERVE, 0, 0); 149 // Printf("%p => %p\n", (void*)start_page, res); 150 char *ch = (char*)res; 151 if (res == (void*)-1L && abort_on_failure) { 152 OutOfMemoryMessage(mem_type, n_pages * kPageSize); 153 ShowStatsAndAbort(); 154 } 155 CHECK(res == (void*)start_page || res == (void*)-1L); 156 return ch; 157} 158 159// mmap range [beg, end] 160static char *mmap_range(uintptr_t beg, uintptr_t end, const char *mem_type) { 161 CHECK((beg % kPageSize) == 0); 162 CHECK(((end + 1) % kPageSize) == 0); 163 // Printf("mmap_range %p %p %ld\n", beg, end, (end - beg) / kPageSize); 164 return mmap_pages(beg, (end - beg + 1) / kPageSize, mem_type); 165} 166 167// protect range [beg, end] 168static void protect_range(uintptr_t beg, uintptr_t end) { 169 CHECK((beg % kPageSize) == 0); 170 CHECK(((end+1) % kPageSize) == 0); 171 // Printf("protect_range %p %p %ld\n", beg, end, (end - beg) / kPageSize); 172 void *res = asan_mmap((void*)beg, end - beg + 1, 173 PROT_NONE, 174 MAP_PRIVATE | MAP_ANON | MAP_FIXED | MAP_NORESERVE, 0, 0); 175 CHECK(res == (void*)beg); 176} 177 178// ---------------------- DescribeAddress -------------------- {{{1 179static bool DescribeStackAddress(uintptr_t addr, uintptr_t access_size) { 180 AsanThread *t = asanThreadRegistry().FindThreadByStackAddress(addr); 181 if (!t) return false; 182 const intptr_t kBufSize = 4095; 183 char buf[kBufSize]; 184 uintptr_t offset = 0; 185 const char *frame_descr = t->GetFrameNameByAddr(addr, &offset); 186 // This string is created by the compiler and has the following form: 187 // "FunctioName n alloc_1 alloc_2 ... alloc_n" 188 // where alloc_i looks like "offset size len ObjectName ". 189 CHECK(frame_descr); 190 // Report the function name and the offset. 191 const char *name_end = real_strchr(frame_descr, ' '); 192 CHECK(name_end); 193 buf[0] = 0; 194 strncat(buf, frame_descr, 195 std::min(kBufSize, static_cast<intptr_t>(name_end - frame_descr))); 196 Printf("Address %p is located at offset %ld " 197 "in frame <%s> of T%d's stack:\n", 198 addr, offset, buf, t->tid()); 199 // Report the number of stack objects. 200 char *p; 201 size_t n_objects = strtol(name_end, &p, 10); 202 CHECK(n_objects > 0); 203 Printf(" This frame has %ld object(s):\n", n_objects); 204 // Report all objects in this frame. 205 for (size_t i = 0; i < n_objects; i++) { 206 size_t beg, size; 207 intptr_t len; 208 beg = strtol(p, &p, 10); 209 size = strtol(p, &p, 10); 210 len = strtol(p, &p, 10); 211 if (beg <= 0 || size <= 0 || len < 0 || *p != ' ') { 212 Printf("AddressSanitizer can't parse the stack frame descriptor: |%s|\n", 213 frame_descr); 214 break; 215 } 216 p++; 217 buf[0] = 0; 218 strncat(buf, p, std::min(kBufSize, len)); 219 p += len; 220 Printf(" [%ld, %ld) '%s'\n", beg, beg + size, buf); 221 } 222 Printf("HINT: this may be a false positive if your program uses " 223 "some custom stack unwind mechanism\n" 224 " (longjmp and C++ exceptions *are* supported)\n"); 225 t->summary()->Announce(); 226 return true; 227} 228 229__attribute__((noinline)) 230static void DescribeAddress(uintptr_t addr, uintptr_t access_size) { 231 // Check if this is a global. 232 if (DescribeAddrIfGlobal(addr)) 233 return; 234 235 if (DescribeStackAddress(addr, access_size)) 236 return; 237 238 // finally, check if this is a heap. 239 DescribeHeapAddress(addr, access_size); 240} 241 242// -------------------------- Run-time entry ------------------- {{{1 243void GetPcSpBpAx(void *context, 244 uintptr_t *pc, uintptr_t *sp, uintptr_t *bp, uintptr_t *ax) { 245 ucontext_t *ucontext = (ucontext_t*)context; 246#ifdef __APPLE__ 247# if __WORDSIZE == 64 248 *pc = ucontext->uc_mcontext->__ss.__rip; 249 *bp = ucontext->uc_mcontext->__ss.__rbp; 250 *sp = ucontext->uc_mcontext->__ss.__rsp; 251 *ax = ucontext->uc_mcontext->__ss.__rax; 252# else 253 *pc = ucontext->uc_mcontext->__ss.__eip; 254 *bp = ucontext->uc_mcontext->__ss.__ebp; 255 *sp = ucontext->uc_mcontext->__ss.__esp; 256 *ax = ucontext->uc_mcontext->__ss.__eax; 257# endif // __WORDSIZE 258#else // assume linux 259# if defined(__arm__) 260 *pc = ucontext->uc_mcontext.arm_pc; 261 *bp = ucontext->uc_mcontext.arm_fp; 262 *sp = ucontext->uc_mcontext.arm_sp; 263 *ax = ucontext->uc_mcontext.arm_r0; 264# elif __WORDSIZE == 64 265 *pc = ucontext->uc_mcontext.gregs[REG_RIP]; 266 *bp = ucontext->uc_mcontext.gregs[REG_RBP]; 267 *sp = ucontext->uc_mcontext.gregs[REG_RSP]; 268 *ax = ucontext->uc_mcontext.gregs[REG_RAX]; 269# else 270 *pc = ucontext->uc_mcontext.gregs[REG_EIP]; 271 *bp = ucontext->uc_mcontext.gregs[REG_EBP]; 272 *sp = ucontext->uc_mcontext.gregs[REG_ESP]; 273 *ax = ucontext->uc_mcontext.gregs[REG_EAX]; 274# endif // __WORDSIZE 275#endif 276} 277 278static void ASAN_OnSIGSEGV(int, siginfo_t *siginfo, void *context) { 279 uintptr_t addr = (uintptr_t)siginfo->si_addr; 280 if (AddrIsInShadow(addr) && FLAG_lazy_shadow) { 281 // We traped on access to a shadow address. Just map a large chunk around 282 // this address. 283 const uintptr_t chunk_size = kPageSize << 10; // 4M 284 uintptr_t chunk = addr & ~(chunk_size - 1); 285 asan_mmap((void*)chunk, chunk_size, 286 PROT_READ | PROT_WRITE, 287 MAP_PRIVATE | MAP_ANON | MAP_FIXED, 0, 0); 288 return; 289 } 290 // Write the first message using the bullet-proof write. 291 if (13 != asan_write(2, "ASAN:SIGSEGV\n", 13)) ASAN_DIE; 292 uintptr_t pc, sp, bp, ax; 293 GetPcSpBpAx(context, &pc, &sp, &bp, &ax); 294 Report("ERROR: AddressSanitizer crashed on unknown address %p" 295 " (pc %p sp %p bp %p ax %p T%d)\n", 296 addr, pc, sp, bp, ax, 297 asanThreadRegistry().GetCurrentTidOrMinusOne()); 298 Printf("AddressSanitizer can not provide additional info. ABORTING\n"); 299 GET_STACK_TRACE_WITH_PC_AND_BP(kStackTraceMax, false, pc, bp); 300 stack.PrintStack(); 301 ShowStatsAndAbort(); 302} 303 304static void ASAN_OnSIGILL(int, siginfo_t *siginfo, void *context) { 305 // Write the first message using the bullet-proof write. 306 if (12 != asan_write(2, "ASAN:SIGILL\n", 12)) ASAN_DIE; 307 uintptr_t pc, sp, bp, ax; 308 GetPcSpBpAx(context, &pc, &sp, &bp, &ax); 309 310 uintptr_t addr = ax; 311 312 uint8_t *insn = (uint8_t*)pc; 313 CHECK(insn[0] == 0x0f && insn[1] == 0x0b); // ud2 314 unsigned access_size_and_type = insn[2] - 0x50; 315 CHECK(access_size_and_type < 16); 316 bool is_write = access_size_and_type & 8; 317 int access_size = 1 << (access_size_and_type & 7); 318 __asan_report_error(pc, bp, sp, addr, is_write, access_size); 319} 320 321// exported functions 322#define ASAN_REPORT_ERROR(type, is_write, size) \ 323extern "C" void __asan_report_ ## type ## size(uintptr_t addr) \ 324 __attribute__((visibility("default"))); \ 325extern "C" void __asan_report_ ## type ## size(uintptr_t addr) { \ 326 GET_BP_PC_SP; \ 327 __asan_report_error(pc, bp, sp, addr, is_write, size); \ 328} 329 330ASAN_REPORT_ERROR(load, false, 1) 331ASAN_REPORT_ERROR(load, false, 2) 332ASAN_REPORT_ERROR(load, false, 4) 333ASAN_REPORT_ERROR(load, false, 8) 334ASAN_REPORT_ERROR(load, false, 16) 335ASAN_REPORT_ERROR(store, true, 1) 336ASAN_REPORT_ERROR(store, true, 2) 337ASAN_REPORT_ERROR(store, true, 4) 338ASAN_REPORT_ERROR(store, true, 8) 339ASAN_REPORT_ERROR(store, true, 16) 340 341// Force the linker to keep the symbols for various ASan interface functions. 342// We want to keep those in the executable in order to let the instrumented 343// dynamic libraries access the symbol even if it is not used by the executable 344// itself. This should help if the build system is removing dead code at link 345// time. 346extern "C" 347void __asan_force_interface_symbols() { 348 volatile int fake_condition = 0; // prevent dead condition elimination. 349 if (fake_condition) { 350 __asan_report_load1(NULL); 351 __asan_report_load2(NULL); 352 __asan_report_load4(NULL); 353 __asan_report_load8(NULL); 354 __asan_report_load16(NULL); 355 __asan_report_store1(NULL); 356 __asan_report_store2(NULL); 357 __asan_report_store4(NULL); 358 __asan_report_store8(NULL); 359 __asan_report_store16(NULL); 360 __asan_register_global(0, 0, NULL); 361 __asan_register_globals(NULL, 0); 362 } 363} 364 365// -------------------------- Init ------------------- {{{1 366static int64_t IntFlagValue(const char *flags, const char *flag, 367 int64_t default_val) { 368 if (!flags) return default_val; 369 const char *str = strstr(flags, flag); 370 if (!str) return default_val; 371 return atoll(str + internal_strlen(flag)); 372} 373 374static void asan_atexit() { 375 Printf("AddressSanitizer exit stats:\n"); 376 __asan_print_accumulated_stats(); 377} 378 379void CheckFailed(const char *cond, const char *file, int line) { 380 Report("CHECK failed: %s at %s:%d, pthread_self=%p\n", 381 cond, file, line, pthread_self()); 382 PRINT_CURRENT_STACK(); 383 ShowStatsAndAbort(); 384} 385 386} // namespace __asan 387 388// -------------------------- Interceptors ------------------- {{{1 389using namespace __asan; // NOLINT 390 391#define OPERATOR_NEW_BODY \ 392 GET_STACK_TRACE_HERE_FOR_MALLOC;\ 393 return asan_memalign(0, size, &stack); 394 395void *operator new(size_t size) throw(std::bad_alloc) { OPERATOR_NEW_BODY; } 396void *operator new[](size_t size) throw(std::bad_alloc) { OPERATOR_NEW_BODY; } 397void *operator new(size_t size, std::nothrow_t const&) throw() 398{ OPERATOR_NEW_BODY; } 399void *operator new[](size_t size, std::nothrow_t const&) throw() 400{ OPERATOR_NEW_BODY; } 401 402#define OPERATOR_DELETE_BODY \ 403 GET_STACK_TRACE_HERE_FOR_FREE(ptr);\ 404 asan_free(ptr, &stack); 405 406void operator delete(void *ptr) throw() { OPERATOR_DELETE_BODY; } 407void operator delete[](void *ptr) throw() { OPERATOR_DELETE_BODY; } 408void operator delete(void *ptr, std::nothrow_t const&) throw() 409{ OPERATOR_DELETE_BODY; } 410void operator delete[](void *ptr, std::nothrow_t const&) throw() 411{ OPERATOR_DELETE_BODY;} 412 413extern "C" 414#ifndef __APPLE__ 415__attribute__((visibility("default"))) 416#endif 417int WRAP(pthread_create)(pthread_t *thread, const pthread_attr_t *attr, 418 void *(*start_routine) (void *), void *arg) { 419 GET_STACK_TRACE_HERE(kStackTraceMax, /*fast_unwind*/false); 420 AsanThread *t = (AsanThread*)asan_malloc(sizeof(AsanThread), &stack); 421 AsanThread *curr_thread = asanThreadRegistry().GetCurrent(); 422 CHECK(curr_thread || asanThreadRegistry().IsCurrentThreadDying()); 423 new(t) AsanThread(asanThreadRegistry().GetCurrentTidOrMinusOne(), 424 start_routine, arg, &stack); 425 return real_pthread_create(thread, attr, asan_thread_start, t); 426} 427 428static bool MySignal(int signum) { 429 if (FLAG_handle_sigill && signum == SIGILL) return true; 430 if (FLAG_handle_segv && signum == SIGSEGV) return true; 431#ifdef __APPLE__ 432 if (FLAG_handle_segv && signum == SIGBUS) return true; 433#endif 434 return false; 435} 436 437static void MaybeInstallSigaction(int signum, 438 void (*handler)(int, siginfo_t *, void *)) { 439 if (!MySignal(signum)) 440 return; 441 struct sigaction sigact; 442 real_memset(&sigact, 0, sizeof(sigact)); 443 sigact.sa_sigaction = handler; 444 sigact.sa_flags = SA_SIGINFO; 445 CHECK(0 == real_sigaction(signum, &sigact, 0)); 446} 447 448extern "C" 449sig_t WRAP(signal)(int signum, sig_t handler) { 450 if (!MySignal(signum)) { 451 return real_signal(signum, handler); 452 } 453 return NULL; 454} 455 456extern "C" 457int WRAP(sigaction)(int signum, const struct sigaction *act, 458 struct sigaction *oldact) { 459 if (!MySignal(signum)) { 460 return real_sigaction(signum, act, oldact); 461 } 462 return 0; 463} 464 465 466static void UnpoisonStackFromHereToTop() { 467 int local_stack; 468 AsanThread *curr_thread = asanThreadRegistry().GetCurrent(); 469 CHECK(curr_thread); 470 uintptr_t top = curr_thread->stack_top(); 471 uintptr_t bottom = ((uintptr_t)&local_stack - kPageSize) & ~(kPageSize-1); 472 PoisonShadow(bottom, top - bottom, 0); 473} 474 475extern "C" void WRAP(longjmp)(void *env, int val) { 476 UnpoisonStackFromHereToTop(); 477 real_longjmp(env, val); 478} 479 480extern "C" void WRAP(_longjmp)(void *env, int val) { 481 UnpoisonStackFromHereToTop(); 482 real__longjmp(env, val); 483} 484 485extern "C" void WRAP(siglongjmp)(void *env, int val) { 486 UnpoisonStackFromHereToTop(); 487 real_siglongjmp(env, val); 488} 489 490extern "C" void __cxa_throw(void *a, void *b, void *c); 491 492#if ASAN_HAS_EXCEPTIONS 493extern "C" void WRAP(__cxa_throw)(void *a, void *b, void *c) { 494 UnpoisonStackFromHereToTop(); 495 real___cxa_throw(a, b, c); 496} 497#endif 498 499extern "C" { 500// intercept mlock and friends. 501// Since asan maps 16T of RAM, mlock is completely unfriendly to asan. 502// All functions return 0 (success). 503static void MlockIsUnsupported() { 504 static bool printed = 0; 505 if (printed) return; 506 printed = true; 507 Printf("INFO: AddressSanitizer ignores mlock/mlockall/munlock/munlockall\n"); 508} 509int mlock(const void *addr, size_t len) { 510 MlockIsUnsupported(); 511 return 0; 512} 513int munlock(const void *addr, size_t len) { 514 MlockIsUnsupported(); 515 return 0; 516} 517int mlockall(int flags) { 518 MlockIsUnsupported(); 519 return 0; 520} 521int munlockall(void) { 522 MlockIsUnsupported(); 523 return 0; 524} 525} // extern "C" 526 527// ---------------------- Interface ---------------- {{{1 528int __asan_set_error_exit_code(int exit_code) { 529 int old = FLAG_exitcode; 530 FLAG_exitcode = exit_code; 531 return old; 532} 533 534void __asan_report_error(uintptr_t pc, uintptr_t bp, uintptr_t sp, 535 uintptr_t addr, bool is_write, size_t access_size) { 536 // Do not print more than one report, otherwise they will mix up. 537 static int num_calls = 0; 538 if (AtomicInc(&num_calls) > 1) return; 539 540 Printf("=================================================================\n"); 541 const char *bug_descr = "unknown-crash"; 542 if (AddrIsInMem(addr)) { 543 uint8_t *shadow_addr = (uint8_t*)MemToShadow(addr); 544 uint8_t shadow_byte = shadow_addr[0]; 545 if (shadow_byte > 0 && shadow_byte < 128) { 546 // we are in the partial right redzone, look at the next shadow byte. 547 shadow_byte = shadow_addr[1]; 548 } 549 switch (shadow_byte) { 550 case kAsanHeapLeftRedzoneMagic: 551 case kAsanHeapRightRedzoneMagic: 552 bug_descr = "heap-buffer-overflow"; 553 break; 554 case kAsanHeapFreeMagic: 555 bug_descr = "heap-use-after-free"; 556 break; 557 case kAsanStackLeftRedzoneMagic: 558 bug_descr = "stack-buffer-underflow"; 559 break; 560 case kAsanStackMidRedzoneMagic: 561 case kAsanStackRightRedzoneMagic: 562 case kAsanStackPartialRedzoneMagic: 563 bug_descr = "stack-buffer-overflow"; 564 break; 565 case kAsanStackAfterReturnMagic: 566 bug_descr = "stack-use-after-return"; 567 break; 568 case kAsanUserPoisonedMemoryMagic: 569 bug_descr = "use-after-poison"; 570 break; 571 case kAsanGlobalRedzoneMagic: 572 bug_descr = "global-buffer-overflow"; 573 break; 574 } 575 } 576 577 Report("ERROR: AddressSanitizer %s on address " 578 "%p at pc 0x%lx bp 0x%lx sp 0x%lx\n", 579 bug_descr, addr, pc, bp, sp); 580 581 Printf("%s of size %d at %p thread T%d\n", 582 access_size ? (is_write ? "WRITE" : "READ") : "ACCESS", 583 access_size, addr, asanThreadRegistry().GetCurrentTidOrMinusOne()); 584 585 if (FLAG_debug) { 586 PrintBytes("PC: ", (uintptr_t*)pc); 587 } 588 589 GET_STACK_TRACE_WITH_PC_AND_BP(kStackTraceMax, 590 false, // FLAG_fast_unwind, 591 pc, bp); 592 stack.PrintStack(); 593 594 CHECK(AddrIsInMem(addr)); 595 596 DescribeAddress(addr, access_size); 597 598 uintptr_t shadow_addr = MemToShadow(addr); 599 Report("ABORTING\n"); 600 __asan_print_accumulated_stats(); 601 Printf("Shadow byte and word:\n"); 602 Printf(" %p: %x\n", shadow_addr, *(unsigned char*)shadow_addr); 603 uintptr_t aligned_shadow = shadow_addr & ~(kWordSize - 1); 604 PrintBytes(" ", (uintptr_t*)(aligned_shadow)); 605 Printf("More shadow bytes:\n"); 606 PrintBytes(" ", (uintptr_t*)(aligned_shadow-4*kWordSize)); 607 PrintBytes(" ", (uintptr_t*)(aligned_shadow-3*kWordSize)); 608 PrintBytes(" ", (uintptr_t*)(aligned_shadow-2*kWordSize)); 609 PrintBytes(" ", (uintptr_t*)(aligned_shadow-1*kWordSize)); 610 PrintBytes("=>", (uintptr_t*)(aligned_shadow+0*kWordSize)); 611 PrintBytes(" ", (uintptr_t*)(aligned_shadow+1*kWordSize)); 612 PrintBytes(" ", (uintptr_t*)(aligned_shadow+2*kWordSize)); 613 PrintBytes(" ", (uintptr_t*)(aligned_shadow+3*kWordSize)); 614 PrintBytes(" ", (uintptr_t*)(aligned_shadow+4*kWordSize)); 615 ASAN_DIE; 616} 617 618void __asan_init() { 619 if (asan_inited) return; 620 asan_init_is_running = true; 621 622 // Make sure we are not statically linked. 623 AsanDoesNotSupportStaticLinkage(); 624 625 // flags 626 const char *options = getenv("ASAN_OPTIONS"); 627 FLAG_malloc_context_size = 628 IntFlagValue(options, "malloc_context_size=", kMallocContextSize); 629 CHECK(FLAG_malloc_context_size <= kMallocContextSize); 630 631 FLAG_max_malloc_fill_size = 632 IntFlagValue(options, "max_malloc_fill_size=", 0); 633 634 FLAG_v = IntFlagValue(options, "verbosity=", 0); 635 636 FLAG_redzone = IntFlagValue(options, "redzone=", 128); 637 CHECK(FLAG_redzone >= 32); 638 CHECK((FLAG_redzone & (FLAG_redzone - 1)) == 0); 639 640 FLAG_atexit = IntFlagValue(options, "atexit=", 0); 641 FLAG_poison_shadow = IntFlagValue(options, "poison_shadow=", 1); 642 FLAG_report_globals = IntFlagValue(options, "report_globals=", 1); 643 FLAG_lazy_shadow = IntFlagValue(options, "lazy_shadow=", 0); 644 FLAG_handle_segv = IntFlagValue(options, "handle_segv=", 645 ASAN_NEEDS_SEGV); 646 FLAG_handle_sigill = IntFlagValue(options, "handle_sigill=", 0); 647 FLAG_stats = IntFlagValue(options, "stats=", 0); 648 FLAG_symbolize = IntFlagValue(options, "symbolize=", 1); 649 FLAG_demangle = IntFlagValue(options, "demangle=", 1); 650 FLAG_debug = IntFlagValue(options, "debug=", 0); 651 FLAG_replace_cfallocator = IntFlagValue(options, "replace_cfallocator=", 1); 652 FLAG_fast_unwind = IntFlagValue(options, "fast_unwind=", 1); 653 FLAG_mt = IntFlagValue(options, "mt=", 1); 654 FLAG_replace_str = IntFlagValue(options, "replace_str=", 1); 655 FLAG_replace_intrin = IntFlagValue(options, "replace_intrin=", 0); 656 FLAG_use_fake_stack = IntFlagValue(options, "use_fake_stack=", 1); 657 FLAG_exitcode = IntFlagValue(options, "exitcode=", EXIT_FAILURE); 658 FLAG_allow_user_poisoning = IntFlagValue(options, 659 "allow_user_poisoning=", 1); 660 661 if (FLAG_atexit) { 662 atexit(asan_atexit); 663 } 664 665 FLAG_quarantine_size = 666 IntFlagValue(options, "quarantine_size=", 1UL << 28); 667 668 // interceptors 669 InitializeAsanInterceptors(); 670 671 ReplaceSystemMalloc(); 672 673 INTERCEPT_FUNCTION(sigaction); 674 INTERCEPT_FUNCTION(signal); 675 INTERCEPT_FUNCTION(longjmp); 676 INTERCEPT_FUNCTION(_longjmp); 677 INTERCEPT_FUNCTION(__cxa_throw); 678 INTERCEPT_FUNCTION(pthread_create); 679#ifdef __APPLE__ 680 INTERCEPT_FUNCTION(dispatch_async_f); 681 INTERCEPT_FUNCTION(dispatch_sync_f); 682 INTERCEPT_FUNCTION(dispatch_after_f); 683 INTERCEPT_FUNCTION(dispatch_barrier_async_f); 684 INTERCEPT_FUNCTION(dispatch_group_async_f); 685 // We don't need to intercept pthread_workqueue_additem_np() to support the 686 // libdispatch API, but it helps us to debug the unsupported functions. Let's 687 // intercept it only during verbose runs. 688 if (FLAG_v >= 2) { 689 INTERCEPT_FUNCTION(pthread_workqueue_additem_np); 690 } 691#else 692 // On Darwin siglongjmp tailcalls longjmp, so we don't want to intercept it 693 // there. 694 INTERCEPT_FUNCTION(siglongjmp); 695#endif 696 697 MaybeInstallSigaction(SIGSEGV, ASAN_OnSIGSEGV); 698 MaybeInstallSigaction(SIGBUS, ASAN_OnSIGSEGV); 699 MaybeInstallSigaction(SIGILL, ASAN_OnSIGILL); 700 701 if (FLAG_v) { 702 Printf("|| `[%p, %p]` || HighMem ||\n", kHighMemBeg, kHighMemEnd); 703 Printf("|| `[%p, %p]` || HighShadow ||\n", 704 kHighShadowBeg, kHighShadowEnd); 705 Printf("|| `[%p, %p]` || ShadowGap ||\n", 706 kShadowGapBeg, kShadowGapEnd); 707 Printf("|| `[%p, %p]` || LowShadow ||\n", 708 kLowShadowBeg, kLowShadowEnd); 709 Printf("|| `[%p, %p]` || LowMem ||\n", kLowMemBeg, kLowMemEnd); 710 Printf("MemToShadow(shadow): %p %p %p %p\n", 711 MEM_TO_SHADOW(kLowShadowBeg), 712 MEM_TO_SHADOW(kLowShadowEnd), 713 MEM_TO_SHADOW(kHighShadowBeg), 714 MEM_TO_SHADOW(kHighShadowEnd)); 715 Printf("red_zone=%ld\n", FLAG_redzone); 716 Printf("malloc_context_size=%ld\n", (int)FLAG_malloc_context_size); 717 Printf("fast_unwind=%d\n", (int)FLAG_fast_unwind); 718 719 Printf("SHADOW_SCALE: %lx\n", SHADOW_SCALE); 720 Printf("SHADOW_GRANULARITY: %lx\n", SHADOW_GRANULARITY); 721 Printf("SHADOW_OFFSET: %lx\n", SHADOW_OFFSET); 722 CHECK(SHADOW_SCALE >= 3 && SHADOW_SCALE <= 7); 723 } 724 725 if (__WORDSIZE == 64) { 726 // Disable core dumper -- it makes little sense to dump 16T+ core. 727 struct rlimit nocore; 728 nocore.rlim_cur = 0; 729 nocore.rlim_max = 0; 730 setrlimit(RLIMIT_CORE, &nocore); 731 } 732 733 { 734 if (!FLAG_lazy_shadow) { 735 if (kLowShadowBeg != kLowShadowEnd) { 736 // mmap the low shadow plus one page. 737 mmap_range(kLowShadowBeg - kPageSize, kLowShadowEnd, "LowShadow"); 738 } 739 // mmap the high shadow. 740 mmap_range(kHighShadowBeg, kHighShadowEnd, "HighShadow"); 741 } 742 // protect the gap 743 protect_range(kShadowGapBeg, kShadowGapEnd); 744 } 745 746 // On Linux AsanThread::ThreadStart() calls malloc() that's why asan_inited 747 // should be set to 1 prior to initializing the threads. 748 asan_inited = 1; 749 asan_init_is_running = false; 750 751 asanThreadRegistry().Init(); 752 asanThreadRegistry().GetMain()->ThreadStart(); 753 __asan_force_interface_symbols(); // no-op. 754 755 if (FLAG_v) { 756 Report("AddressSanitizer Init done\n"); 757 } 758} 759