libsanitizer/asan/asan_report.cc

   1 //===-- asan_report.cc ----------------------------------------------------===//
   2 //
   3 // This file is distributed under the University of Illinois Open Source
   4 // License. See LICENSE.TXT for details.
   5 //
   6 //===----------------------------------------------------------------------===//
   7 //
   8 // This file is a part of AddressSanitizer, an address sanity checker.
   9 //
  10 // This file contains error reporting code.
  11 //===----------------------------------------------------------------------===//
  12 #include "asan_flags.h"
  13 #include "asan_internal.h"
  14 #include "asan_mapping.h"
  15 #include "asan_report.h"
  16 #include "asan_stack.h"
  17 #include "asan_thread.h"
  18 #include "sanitizer_common/sanitizer_common.h"
  19 #include "sanitizer_common/sanitizer_flags.h"
  20 #include "sanitizer_common/sanitizer_report_decorator.h"
  21 #include "sanitizer_common/sanitizer_stackdepot.h"
  22 #include "sanitizer_common/sanitizer_symbolizer.h"
  23
  24 namespace __asan {
  25
  26 // -------------------- User-specified callbacks ----------------- {{{1
  27 static void (*error_report_callback)(const char*);
  28 static char *error_message_buffer = 0;
  29 static uptr error_message_buffer_pos = 0;
  30 static uptr error_message_buffer_size = 0;
  31
  32 void AppendToErrorMessageBuffer(const char *buffer) {
  33   if (error_message_buffer) {
  34     uptr length = internal_strlen(buffer);
  35     CHECK_GE(error_message_buffer_size, error_message_buffer_pos);
  36     uptr remaining = error_message_buffer_size - error_message_buffer_pos;
  37     internal_strncpy(error_message_buffer + error_message_buffer_pos,
  38                      buffer, remaining);
  39     error_message_buffer[error_message_buffer_size - 1] = '\0';
  40     // FIXME: reallocate the buffer instead of truncating the message.
  41     error_message_buffer_pos += remaining > length ? length : remaining;
  42   }
  43 }
  44
  45 // ---------------------- Decorator ------------------------------ {{{1
  46 class Decorator: private __sanitizer::AnsiColorDecorator {
  47  public:
  48   Decorator() : __sanitizer::AnsiColorDecorator(PrintsToTtyCached()) { }
  49   const char *Warning()    { return Red(); }
  50   const char *EndWarning() { return Default(); }
  51   const char *Access()     { return Blue(); }
  52   const char *EndAccess()  { return Default(); }
  53   const char *Location()   { return Green(); }
  54   const char *EndLocation() { return Default(); }
  55   const char *Allocation()  { return Magenta(); }
  56   const char *EndAllocation()  { return Default(); }
  57
  58   const char *ShadowByte(u8 byte) {
  59     switch (byte) {
  60       case kAsanHeapLeftRedzoneMagic:
  61       case kAsanHeapRightRedzoneMagic:
  62         return Red();
  63       case kAsanHeapFreeMagic:
  64         return Magenta();
  65       case kAsanStackLeftRedzoneMagic:
  66       case kAsanStackMidRedzoneMagic:
  67       case kAsanStackRightRedzoneMagic:
  68       case kAsanStackPartialRedzoneMagic:
  69         return Red();
  70       case kAsanStackAfterReturnMagic:
  71         return Magenta();
  72       case kAsanInitializationOrderMagic:
  73         return Cyan();
  74       case kAsanUserPoisonedMemoryMagic:
  75       case kAsanContiguousContainerOOBMagic:
  76         return Blue();
  77       case kAsanStackUseAfterScopeMagic:
  78         return Magenta();
  79       case kAsanGlobalRedzoneMagic:
  80         return Red();
  81       case kAsanInternalHeapMagic:
  82         return Yellow();
  83       default:
  84         return Default();
  85     }
  86   }
  87   const char *EndShadowByte() { return Default(); }
  88 };
  89
  90 // ---------------------- Helper functions ----------------------- {{{1
  91
  92 static void PrintShadowByte(const char *before, u8 byte,
  93                             const char *after = "\n") {
  94   Decorator d;
  95   Printf("%s%s%x%x%s%s", before,
  96          d.ShadowByte(byte), byte >> 4, byte & 15, d.EndShadowByte(), after);
  97 }
  98
  99 static void PrintShadowBytes(const char *before, u8 *bytes,
 100                              u8 *guilty, uptr n) {
 101   Decorator d;
 102   if (before)
 103     Printf("%s%p:", before, bytes);
 104   for (uptr i = 0; i < n; i++) {
 105     u8 *p = bytes + i;
 106     const char *before = p == guilty ? "[" :
 107         (p - 1 == guilty && i != 0) ? "" : " ";
 108     const char *after = p == guilty ? "]" : "";
 109     PrintShadowByte(before, *p, after);
 110   }
 111   Printf("\n");
 112 }
 113
 114 static void PrintLegend() {
 115   Printf("Shadow byte legend (one shadow byte represents %d "
 116          "application bytes):\n", (int)SHADOW_GRANULARITY);
 117   PrintShadowByte("  Addressable:           ", 0);
 118   Printf("  Partially addressable: ");
 119   for (u8 i = 1; i < SHADOW_GRANULARITY; i++)
 120     PrintShadowByte("", i, " ");
 121   Printf("\n");
 122   PrintShadowByte("  Heap left redzone:       ", kAsanHeapLeftRedzoneMagic);
 123   PrintShadowByte("  Heap right redzone:      ", kAsanHeapRightRedzoneMagic);
 124   PrintShadowByte("  Freed heap region:       ", kAsanHeapFreeMagic);
 125   PrintShadowByte("  Stack left redzone:      ", kAsanStackLeftRedzoneMagic);
 126   PrintShadowByte("  Stack mid redzone:       ", kAsanStackMidRedzoneMagic);
 127   PrintShadowByte("  Stack right redzone:     ", kAsanStackRightRedzoneMagic);
 128   PrintShadowByte("  Stack partial redzone:   ", kAsanStackPartialRedzoneMagic);
 129   PrintShadowByte("  Stack after return:      ", kAsanStackAfterReturnMagic);
 130   PrintShadowByte("  Stack use after scope:   ", kAsanStackUseAfterScopeMagic);
 131   PrintShadowByte("  Global redzone:          ", kAsanGlobalRedzoneMagic);
 132   PrintShadowByte("  Global init order:       ", kAsanInitializationOrderMagic);
 133   PrintShadowByte("  Poisoned by user:        ", kAsanUserPoisonedMemoryMagic);
 134   PrintShadowByte("  Contiguous container OOB:",
 135                   kAsanContiguousContainerOOBMagic);
 136   PrintShadowByte("  ASan internal:           ", kAsanInternalHeapMagic);
 137 }
 138
 139 static void PrintShadowMemoryForAddress(uptr addr) {
 140   if (!AddrIsInMem(addr))
 141     return;
 142   uptr shadow_addr = MemToShadow(addr);
 143   const uptr n_bytes_per_row = 16;
 144   uptr aligned_shadow = shadow_addr & ~(n_bytes_per_row - 1);
 145   Printf("Shadow bytes around the buggy address:\n");
 146   for (int i = -5; i <= 5; i++) {
 147     const char *prefix = (i == 0) ? "=>" : "  ";
 148     PrintShadowBytes(prefix,
 149                      (u8*)(aligned_shadow + i * n_bytes_per_row),
 150                      (u8*)shadow_addr, n_bytes_per_row);
 151   }
 152   if (flags()->print_legend)
 153     PrintLegend();
 154 }
 155
 156 static void PrintZoneForPointer(uptr ptr, uptr zone_ptr,
 157                                 const char *zone_name) {
 158   if (zone_ptr) {
 159     if (zone_name) {
 160       Printf("malloc_zone_from_ptr(%p) = %p, which is %s\n",
 161                  ptr, zone_ptr, zone_name);
 162     } else {
 163       Printf("malloc_zone_from_ptr(%p) = %p, which doesn't have a name\n",
 164                  ptr, zone_ptr);
 165     }
 166   } else {
 167     Printf("malloc_zone_from_ptr(%p) = 0\n", ptr);
 168   }
 169 }
 170
 171 static void DescribeThread(AsanThread *t) {
 172   if (t)
 173     DescribeThread(t->context());
 174 }
 175
 176 // ---------------------- Address Descriptions ------------------- {{{1
 177
 178 static bool IsASCII(unsigned char c) {
 179   return /*0x00 <= c &&*/ c <= 0x7F;
 180 }
 181
 182 static const char *MaybeDemangleGlobalName(const char *name) {
 183   // We can spoil names of globals with C linkage, so use an heuristic
 184   // approach to check if the name should be demangled.
 185   return (name[0] == '_' && name[1] == 'Z')
 186              ? Symbolizer::Get()->Demangle(name)
 187              : name;
 188 }
 189
 190 // Check if the global is a zero-terminated ASCII string. If so, print it.
 191 static void PrintGlobalNameIfASCII(const __asan_global &g) {
 192   for (uptr p = g.beg; p < g.beg + g.size - 1; p++) {
 193     unsigned char c = *(unsigned char*)p;
 194     if (c == '\0' || !IsASCII(c)) return;
 195   }
 196   if (*(char*)(g.beg + g.size - 1) != '\0') return;
 197   Printf("  '%s' is ascii string '%s'\n",
 198          MaybeDemangleGlobalName(g.name), (char*)g.beg);
 199 }
 200
 201 bool DescribeAddressRelativeToGlobal(uptr addr, uptr size,
 202                                      const __asan_global &g) {
 203   static const uptr kMinimalDistanceFromAnotherGlobal = 64;
 204   if (addr <= g.beg - kMinimalDistanceFromAnotherGlobal) return false;
 205   if (addr >= g.beg + g.size_with_redzone) return false;
 206   Decorator d;
 207   Printf("%s", d.Location());
 208   if (addr < g.beg) {
 209     Printf("%p is located %zd bytes to the left", (void*)addr, g.beg - addr);
 210   } else if (addr + size > g.beg + g.size) {
 211     if (addr < g.beg + g.size)
 212       addr = g.beg + g.size;
 213     Printf("%p is located %zd bytes to the right", (void*)addr,
 214            addr - (g.beg + g.size));
 215   } else {
 216     // Can it happen?
 217     Printf("%p is located %zd bytes inside", (void*)addr, addr - g.beg);
 218   }
 219   Printf(" of global variable '%s' from '%s' (0x%zx) of size %zu\n",
 220              MaybeDemangleGlobalName(g.name), g.module_name, g.beg, g.size);
 221   Printf("%s", d.EndLocation());
 222   PrintGlobalNameIfASCII(g);
 223   return true;
 224 }
 225
 226 bool DescribeAddressIfShadow(uptr addr) {
 227   if (AddrIsInMem(addr))
 228     return false;
 229   static const char kAddrInShadowReport[] =
 230       "Address %p is located in the %s.\n";
 231   if (AddrIsInShadowGap(addr)) {
 232     Printf(kAddrInShadowReport, addr, "shadow gap area");
 233     return true;
 234   }
 235   if (AddrIsInHighShadow(addr)) {
 236     Printf(kAddrInShadowReport, addr, "high shadow area");
 237     return true;
 238   }
 239   if (AddrIsInLowShadow(addr)) {
 240     Printf(kAddrInShadowReport, addr, "low shadow area");
 241     return true;
 242   }
 243   CHECK(0 && "Address is not in memory and not in shadow?");
 244   return false;
 245 }
 246
 247 // Return " (thread_name) " or an empty string if the name is empty.
 248 const char *ThreadNameWithParenthesis(AsanThreadContext *t, char buff[],
 249                                       uptr buff_len) {
 250   const char *name = t->name;
 251   if (name[0] == '\0') return "";
 252   buff[0] = 0;
 253   internal_strncat(buff, " (", 3);
 254   internal_strncat(buff, name, buff_len - 4);
 255   internal_strncat(buff, ")", 2);
 256   return buff;
 257 }
 258
 259 const char *ThreadNameWithParenthesis(u32 tid, char buff[],
 260                                       uptr buff_len) {
 261   if (tid == kInvalidTid) return "";
 262   asanThreadRegistry().CheckLocked();
 263   AsanThreadContext *t = GetThreadContextByTidLocked(tid);
 264   return ThreadNameWithParenthesis(t, buff, buff_len);
 265 }
 266
 267 void PrintAccessAndVarIntersection(const char *var_name,
 268                                    uptr var_beg, uptr var_size,
 269                                    uptr addr, uptr access_size,
 270                                    uptr prev_var_end, uptr next_var_beg) {
 271   uptr var_end = var_beg + var_size;
 272   uptr addr_end = addr + access_size;
 273   const char *pos_descr = 0;
 274   // If the variable [var_beg, var_end) is the nearest variable to the
 275   // current memory access, indicate it in the log.
 276   if (addr >= var_beg) {
 277     if (addr_end <= var_end)
 278       pos_descr = "is inside";  // May happen if this is a use-after-return.
 279     else if (addr < var_end)
 280       pos_descr = "partially overflows";
 281     else if (addr_end <= next_var_beg &&
 282              next_var_beg - addr_end >= addr - var_end)
 283       pos_descr = "overflows";
 284   } else {
 285     if (addr_end > var_beg)
 286       pos_descr = "partially underflows";
 287     else if (addr >= prev_var_end &&
 288              addr - prev_var_end >= var_beg - addr_end)
 289       pos_descr = "underflows";
 290   }
 291   Printf("    [%zd, %zd) '%s'", var_beg, var_beg + var_size, var_name);
 292   if (pos_descr) {
 293     Decorator d;
 294     // FIXME: we may want to also print the size of the access here,
 295     // but in case of accesses generated by memset it may be confusing.
 296     Printf("%s <== Memory access at offset %zd %s this variable%s\n",
 297            d.Location(), addr, pos_descr, d.EndLocation());
 298   } else {
 299     Printf("\n");
 300   }
 301 }
 302
 303 struct StackVarDescr {
 304   uptr beg;
 305   uptr size;
 306   const char *name_pos;
 307   uptr name_len;
 308 };
 309
 310 bool DescribeAddressIfStack(uptr addr, uptr access_size) {
 311   AsanThread *t = FindThreadByStackAddress(addr);
 312   if (!t) return false;
 313   const uptr kBufSize = 4095;
 314   char buf[kBufSize];
 315   uptr offset = 0;
 316   uptr frame_pc = 0;
 317   char tname[128];
 318   const char *frame_descr = t->GetFrameNameByAddr(addr, &offset, &frame_pc);
 319
 320 #ifdef __powerpc64__
 321   // On PowerPC64, the address of a function actually points to a
 322   // three-doubleword data structure with the first field containing
 323   // the address of the function's code.
 324   frame_pc = *reinterpret_cast<uptr *>(frame_pc);
 325 #endif
 326
 327   // This string is created by the compiler and has the following form:
 328   // "n alloc_1 alloc_2 ... alloc_n"
 329   // where alloc_i looks like "offset size len ObjectName ".
 330   CHECK(frame_descr);
 331   Decorator d;
 332   Printf("%s", d.Location());
 333   Printf("Address %p is located in stack of thread T%d%s "
 334          "at offset %zu in frame\n",
 335          addr, t->tid(),
 336          ThreadNameWithParenthesis(t->tid(), tname, sizeof(tname)),
 337          offset);
 338   // Now we print the frame where the alloca has happened.
 339   // We print this frame as a stack trace with one element.
 340   // The symbolizer may print more than one frame if inlining was involved.
 341   // The frame numbers may be different than those in the stack trace printed
 342   // previously. That's unfortunate, but I have no better solution,
 343   // especially given that the alloca may be from entirely different place
 344   // (e.g. use-after-scope, or different thread's stack).
 345   StackTrace alloca_stack;
 346   alloca_stack.trace[0] = frame_pc + 16;
 347   alloca_stack.size = 1;
 348   Printf("%s", d.EndLocation());
 349   PrintStack(&alloca_stack);
 350   // Report the number of stack objects.
 351   char *p;
 352   uptr n_objects = (uptr)internal_simple_strtoll(frame_descr, &p, 10);
 353   CHECK_GT(n_objects, 0);
 354   Printf("  This frame has %zu object(s):\n", n_objects);
 355
 356   // Report all objects in this frame.
 357   InternalScopedBuffer<StackVarDescr> vars(n_objects);
 358   for (uptr i = 0; i < n_objects; i++) {
 359     uptr beg, size;
 360     uptr len;
 361     beg  = (uptr)internal_simple_strtoll(p, &p, 10);
 362     size = (uptr)internal_simple_strtoll(p, &p, 10);
 363     len  = (uptr)internal_simple_strtoll(p, &p, 10);
 364     if (beg == 0 || size == 0 || *p != ' ') {
 365       Printf("AddressSanitizer can't parse the stack frame "
 366                  "descriptor: |%s|\n", frame_descr);
 367       break;
 368     }
 369     p++;
 370     vars[i].beg = beg;
 371     vars[i].size = size;
 372     vars[i].name_pos = p;
 373     vars[i].name_len = len;
 374     p += len;
 375   }
 376   for (uptr i = 0; i < n_objects; i++) {
 377     buf[0] = 0;
 378     internal_strncat(buf, vars[i].name_pos,
 379                      static_cast<uptr>(Min(kBufSize, vars[i].name_len)));
 380     uptr prev_var_end = i ? vars[i - 1].beg + vars[i - 1].size : 0;
 381     uptr next_var_beg = i + 1 < n_objects ? vars[i + 1].beg : ~(0UL);
 382     PrintAccessAndVarIntersection(buf, vars[i].beg, vars[i].size,
 383                                   offset, access_size,
 384                                   prev_var_end, next_var_beg);
 385   }
 386   Printf("HINT: this may be a false positive if your program uses "
 387              "some custom stack unwind mechanism or swapcontext\n"
 388              "      (longjmp and C++ exceptions *are* supported)\n");
 389   DescribeThread(t);
 390   return true;
 391 }
 392
 393 static void DescribeAccessToHeapChunk(AsanChunkView chunk, uptr addr,
 394                                       uptr access_size) {
 395   sptr offset;
 396   Decorator d;
 397   Printf("%s", d.Location());
 398   if (chunk.AddrIsAtLeft(addr, access_size, &offset)) {
 399     Printf("%p is located %zd bytes to the left of", (void*)addr, offset);
 400   } else if (chunk.AddrIsAtRight(addr, access_size, &offset)) {
 401     if (offset < 0) {
 402       addr -= offset;
 403       offset = 0;
 404     }
 405     Printf("%p is located %zd bytes to the right of", (void*)addr, offset);
 406   } else if (chunk.AddrIsInside(addr, access_size, &offset)) {
 407     Printf("%p is located %zd bytes inside of", (void*)addr, offset);
 408   } else {
 409     Printf("%p is located somewhere around (this is AddressSanitizer bug!)",
 410            (void*)addr);
 411   }
 412   Printf(" %zu-byte region [%p,%p)\n", chunk.UsedSize(),
 413          (void*)(chunk.Beg()), (void*)(chunk.End()));
 414   Printf("%s", d.EndLocation());
 415 }
 416
 417 void DescribeHeapAddress(uptr addr, uptr access_size) {
 418   AsanChunkView chunk = FindHeapChunkByAddress(addr);
 419   if (!chunk.IsValid()) {
 420     Printf("AddressSanitizer can not describe address in more detail "
 421            "(wild memory access suspected).\n");
 422     return;
 423   }
 424   DescribeAccessToHeapChunk(chunk, addr, access_size);
 425   CHECK(chunk.AllocTid() != kInvalidTid);
 426   asanThreadRegistry().CheckLocked();
 427   AsanThreadContext *alloc_thread =
 428       GetThreadContextByTidLocked(chunk.AllocTid());
 429   StackTrace alloc_stack;
 430   chunk.GetAllocStack(&alloc_stack);
 431   char tname[128];
 432   Decorator d;
 433   AsanThreadContext *free_thread = 0;
 434   if (chunk.FreeTid() != kInvalidTid) {
 435     free_thread = GetThreadContextByTidLocked(chunk.FreeTid());
 436     Printf("%sfreed by thread T%d%s here:%s\n", d.Allocation(),
 437            free_thread->tid,
 438            ThreadNameWithParenthesis(free_thread, tname, sizeof(tname)),
 439            d.EndAllocation());
 440     StackTrace free_stack;
 441     chunk.GetFreeStack(&free_stack);
 442     PrintStack(&free_stack);
 443     Printf("%spreviously allocated by thread T%d%s here:%s\n",
 444            d.Allocation(), alloc_thread->tid,
 445            ThreadNameWithParenthesis(alloc_thread, tname, sizeof(tname)),
 446            d.EndAllocation());
 447   } else {
 448     Printf("%sallocated by thread T%d%s here:%s\n", d.Allocation(),
 449            alloc_thread->tid,
 450            ThreadNameWithParenthesis(alloc_thread, tname, sizeof(tname)),
 451            d.EndAllocation());
 452   }
 453   PrintStack(&alloc_stack);
 454   DescribeThread(GetCurrentThread());
 455   if (free_thread)
 456     DescribeThread(free_thread);
 457   DescribeThread(alloc_thread);
 458 }
 459
 460 void DescribeAddress(uptr addr, uptr access_size) {
 461   // Check if this is shadow or shadow gap.
 462   if (DescribeAddressIfShadow(addr))
 463     return;
 464   CHECK(AddrIsInMem(addr));
 465   if (DescribeAddressIfGlobal(addr, access_size))
 466     return;
 467   if (DescribeAddressIfStack(addr, access_size))
 468     return;
 469   // Assume it is a heap address.
 470   DescribeHeapAddress(addr, access_size);
 471 }
 472
 473 // ------------------- Thread description -------------------- {{{1
 474
 475 void DescribeThread(AsanThreadContext *context) {
 476   CHECK(context);
 477   asanThreadRegistry().CheckLocked();
 478   // No need to announce the main thread.
 479   if (context->tid == 0 || context->announced) {
 480     return;
 481   }
 482   context->announced = true;
 483   char tname[128];
 484   Printf("Thread T%d%s", context->tid,
 485          ThreadNameWithParenthesis(context->tid, tname, sizeof(tname)));
 486   Printf(" created by T%d%s here:\n",
 487          context->parent_tid,
 488          ThreadNameWithParenthesis(context->parent_tid,
 489                                    tname, sizeof(tname)));
 490   uptr stack_size;
 491   const uptr *stack_trace = StackDepotGet(context->stack_id, &stack_size);
 492   PrintStack(stack_trace, stack_size);
 493   // Recursively described parent thread if needed.
 494   if (flags()->print_full_thread_history) {
 495     AsanThreadContext *parent_context =
 496         GetThreadContextByTidLocked(context->parent_tid);
 497     DescribeThread(parent_context);
 498   }
 499 }
 500
 501 // -------------------- Different kinds of reports ----------------- {{{1
 502
 503 // Use ScopedInErrorReport to run common actions just before and
 504 // immediately after printing error report.
 505 class ScopedInErrorReport {
 506  public:
 507   ScopedInErrorReport() {
 508     static atomic_uint32_t num_calls;
 509     static u32 reporting_thread_tid;
 510     if (atomic_fetch_add(&num_calls, 1, memory_order_relaxed) != 0) {
 511       // Do not print more than one report, otherwise they will mix up.
 512       // Error reporting functions shouldn't return at this situation, as
 513       // they are defined as no-return.
 514       Report("AddressSanitizer: while reporting a bug found another one."
 515                  "Ignoring.\n");
 516       u32 current_tid = GetCurrentTidOrInvalid();
 517       if (current_tid != reporting_thread_tid) {
 518         // ASan found two bugs in different threads simultaneously. Sleep
 519         // long enough to make sure that the thread which started to print
 520         // an error report will finish doing it.
 521         SleepForSeconds(Max(100, flags()->sleep_before_dying + 1));
 522       }
 523       // If we're still not dead for some reason, use raw _exit() instead of
 524       // Die() to bypass any additional checks.
 525       internal__exit(flags()->exitcode);
 526     }
 527     ASAN_ON_ERROR();
 528     // Make sure the registry and sanitizer report mutexes are locked while
 529     // we're printing an error report.
 530     // We can lock them only here to avoid self-deadlock in case of
 531     // recursive reports.
 532     asanThreadRegistry().Lock();
 533     CommonSanitizerReportMutex.Lock();
 534     reporting_thread_tid = GetCurrentTidOrInvalid();
 535     Printf("===================================================="
 536            "=============\n");
 537   }
 538   // Destructor is NORETURN, as functions that report errors are.
 539   NORETURN ~ScopedInErrorReport() {
 540     // Make sure the current thread is announced.
 541     DescribeThread(GetCurrentThread());
 542     // Print memory stats.
 543     if (flags()->print_stats)
 544       __asan_print_accumulated_stats();
 545     if (error_report_callback) {
 546       error_report_callback(error_message_buffer);
 547     }
 548     Report("ABORTING\n");
 549     Die();
 550   }
 551 };
 552
 553 void ReportSIGSEGV(uptr pc, uptr sp, uptr bp, uptr addr) {
 554   ScopedInErrorReport in_report;
 555   Decorator d;
 556   Printf("%s", d.Warning());
 557   Report("ERROR: AddressSanitizer: SEGV on unknown address %p"
 558              " (pc %p sp %p bp %p T%d)\n",
 559              (void*)addr, (void*)pc, (void*)sp, (void*)bp,
 560              GetCurrentTidOrInvalid());
 561   Printf("%s", d.EndWarning());
 562   GET_STACK_TRACE_FATAL(pc, bp);
 563   PrintStack(&stack);
 564   Printf("AddressSanitizer can not provide additional info.\n");
 565   ReportErrorSummary("SEGV", &stack);
 566 }
 567
 568 void ReportDoubleFree(uptr addr, StackTrace *free_stack) {
 569   ScopedInErrorReport in_report;
 570   Decorator d;
 571   Printf("%s", d.Warning());
 572   char tname[128];
 573   u32 curr_tid = GetCurrentTidOrInvalid();
 574   Report("ERROR: AddressSanitizer: attempting double-free on %p in "
 575          "thread T%d%s:\n",
 576          addr, curr_tid,
 577          ThreadNameWithParenthesis(curr_tid, tname, sizeof(tname)));
 578   Printf("%s", d.EndWarning());
 579   CHECK_GT(free_stack->size, 0);
 580   GET_STACK_TRACE_FATAL(free_stack->trace[0], free_stack->top_frame_bp);
 581   PrintStack(&stack);
 582   DescribeHeapAddress(addr, 1);
 583   ReportErrorSummary("double-free", &stack);
 584 }
 585
 586 void ReportFreeNotMalloced(uptr addr, StackTrace *free_stack) {
 587   ScopedInErrorReport in_report;
 588   Decorator d;
 589   Printf("%s", d.Warning());
 590   char tname[128];
 591   u32 curr_tid = GetCurrentTidOrInvalid();
 592   Report("ERROR: AddressSanitizer: attempting free on address "
 593              "which was not malloc()-ed: %p in thread T%d%s\n", addr,
 594          curr_tid, ThreadNameWithParenthesis(curr_tid, tname, sizeof(tname)));
 595   Printf("%s", d.EndWarning());
 596   CHECK_GT(free_stack->size, 0);
 597   GET_STACK_TRACE_FATAL(free_stack->trace[0], free_stack->top_frame_bp);
 598   PrintStack(&stack);
 599   DescribeHeapAddress(addr, 1);
 600   ReportErrorSummary("bad-free", &stack);
 601 }
 602
 603 void ReportAllocTypeMismatch(uptr addr, StackTrace *free_stack,
 604                              AllocType alloc_type,
 605                              AllocType dealloc_type) {
 606   static const char *alloc_names[] =
 607     {"INVALID", "malloc", "operator new", "operator new []"};
 608   static const char *dealloc_names[] =
 609     {"INVALID", "free", "operator delete", "operator delete []"};
 610   CHECK_NE(alloc_type, dealloc_type);
 611   ScopedInErrorReport in_report;
 612   Decorator d;
 613   Printf("%s", d.Warning());
 614   Report("ERROR: AddressSanitizer: alloc-dealloc-mismatch (%s vs %s) on %p\n",
 615         alloc_names[alloc_type], dealloc_names[dealloc_type], addr);
 616   Printf("%s", d.EndWarning());
 617   CHECK_GT(free_stack->size, 0);
 618   GET_STACK_TRACE_FATAL(free_stack->trace[0], free_stack->top_frame_bp);
 619   PrintStack(&stack);
 620   DescribeHeapAddress(addr, 1);
 621   ReportErrorSummary("alloc-dealloc-mismatch", &stack);
 622   Report("HINT: if you don't care about these warnings you may set "
 623          "ASAN_OPTIONS=alloc_dealloc_mismatch=0\n");
 624 }
 625
 626 void ReportMallocUsableSizeNotOwned(uptr addr, StackTrace *stack) {
 627   ScopedInErrorReport in_report;
 628   Decorator d;
 629   Printf("%s", d.Warning());
 630   Report("ERROR: AddressSanitizer: attempting to call "
 631              "malloc_usable_size() for pointer which is "
 632              "not owned: %p\n", addr);
 633   Printf("%s", d.EndWarning());
 634   PrintStack(stack);
 635   DescribeHeapAddress(addr, 1);
 636   ReportErrorSummary("bad-malloc_usable_size", stack);
 637 }
 638
 639 void ReportAsanGetAllocatedSizeNotOwned(uptr addr, StackTrace *stack) {
 640   ScopedInErrorReport in_report;
 641   Decorator d;
 642   Printf("%s", d.Warning());
 643   Report("ERROR: AddressSanitizer: attempting to call "
 644              "__asan_get_allocated_size() for pointer which is "
 645              "not owned: %p\n", addr);
 646   Printf("%s", d.EndWarning());
 647   PrintStack(stack);
 648   DescribeHeapAddress(addr, 1);
 649   ReportErrorSummary("bad-__asan_get_allocated_size", stack);
 650 }
 651
 652 void ReportStringFunctionMemoryRangesOverlap(
 653     const char *function, const char *offset1, uptr length1,
 654     const char *offset2, uptr length2, StackTrace *stack) {
 655   ScopedInErrorReport in_report;
 656   Decorator d;
 657   char bug_type[100];
 658   internal_snprintf(bug_type, sizeof(bug_type), "%s-param-overlap", function);
 659   Printf("%s", d.Warning());
 660   Report("ERROR: AddressSanitizer: %s: "
 661              "memory ranges [%p,%p) and [%p, %p) overlap\n", \
 662              bug_type, offset1, offset1 + length1, offset2, offset2 + length2);
 663   Printf("%s", d.EndWarning());
 664   PrintStack(stack);
 665   DescribeAddress((uptr)offset1, length1);
 666   DescribeAddress((uptr)offset2, length2);
 667   ReportErrorSummary(bug_type, stack);
 668 }
 669
 670 // ----------------------- Mac-specific reports ----------------- {{{1
 671
 672 void WarnMacFreeUnallocated(
 673     uptr addr, uptr zone_ptr, const char *zone_name, StackTrace *stack) {
 674   // Just print a warning here.
 675   Printf("free_common(%p) -- attempting to free unallocated memory.\n"
 676              "AddressSanitizer is ignoring this error on Mac OS now.\n",
 677              addr);
 678   PrintZoneForPointer(addr, zone_ptr, zone_name);
 679   PrintStack(stack);
 680   DescribeHeapAddress(addr, 1);
 681 }
 682
 683 void ReportMacMzReallocUnknown(
 684     uptr addr, uptr zone_ptr, const char *zone_name, StackTrace *stack) {
 685   ScopedInErrorReport in_report;
 686   Printf("mz_realloc(%p) -- attempting to realloc unallocated memory.\n"
 687              "This is an unrecoverable problem, exiting now.\n",
 688              addr);
 689   PrintZoneForPointer(addr, zone_ptr, zone_name);
 690   PrintStack(stack);
 691   DescribeHeapAddress(addr, 1);
 692 }
 693
 694 void ReportMacCfReallocUnknown(
 695     uptr addr, uptr zone_ptr, const char *zone_name, StackTrace *stack) {
 696   ScopedInErrorReport in_report;
 697   Printf("cf_realloc(%p) -- attempting to realloc unallocated memory.\n"
 698              "This is an unrecoverable problem, exiting now.\n",
 699              addr);
 700   PrintZoneForPointer(addr, zone_ptr, zone_name);
 701   PrintStack(stack);
 702   DescribeHeapAddress(addr, 1);
 703 }
 704
 705 }  // namespace __asan
 706
 707 // --------------------------- Interface --------------------- {{{1
 708 using namespace __asan;  // NOLINT
 709
 710 void __asan_report_error(uptr pc, uptr bp, uptr sp,
 711                          uptr addr, bool is_write, uptr access_size) {
 712   ScopedInErrorReport in_report;
 713
 714   // Determine the error type.
 715   const char *bug_descr = "unknown-crash";
 716   if (AddrIsInMem(addr)) {
 717     u8 *shadow_addr = (u8*)MemToShadow(addr);
 718     // If we are accessing 16 bytes, look at the second shadow byte.
 719     if (*shadow_addr == 0 && access_size > SHADOW_GRANULARITY)
 720       shadow_addr++;
 721     // If we are in the partial right redzone, look at the next shadow byte.
 722     if (*shadow_addr > 0 && *shadow_addr < 128)
 723       shadow_addr++;
 724     switch (*shadow_addr) {
 725       case kAsanHeapLeftRedzoneMagic:
 726       case kAsanHeapRightRedzoneMagic:
 727         bug_descr = "heap-buffer-overflow";
 728         break;
 729       case kAsanHeapFreeMagic:
 730         bug_descr = "heap-use-after-free";
 731         break;
 732       case kAsanStackLeftRedzoneMagic:
 733         bug_descr = "stack-buffer-underflow";
 734         break;
 735       case kAsanInitializationOrderMagic:
 736         bug_descr = "initialization-order-fiasco";
 737         break;
 738       case kAsanStackMidRedzoneMagic:
 739       case kAsanStackRightRedzoneMagic:
 740       case kAsanStackPartialRedzoneMagic:
 741         bug_descr = "stack-buffer-overflow";
 742         break;
 743       case kAsanStackAfterReturnMagic:
 744         bug_descr = "stack-use-after-return";
 745         break;
 746       case kAsanUserPoisonedMemoryMagic:
 747         bug_descr = "use-after-poison";
 748         break;
 749       case kAsanContiguousContainerOOBMagic:
 750         bug_descr = "container-overflow";
 751         break;
 752       case kAsanStackUseAfterScopeMagic:
 753         bug_descr = "stack-use-after-scope";
 754         break;
 755       case kAsanGlobalRedzoneMagic:
 756         bug_descr = "global-buffer-overflow";
 757         break;
 758     }
 759   }
 760   Decorator d;
 761   Printf("%s", d.Warning());
 762   Report("ERROR: AddressSanitizer: %s on address "
 763              "%p at pc 0x%zx bp 0x%zx sp 0x%zx\n",
 764              bug_descr, (void*)addr, pc, bp, sp);
 765   Printf("%s", d.EndWarning());
 766
 767   u32 curr_tid = GetCurrentTidOrInvalid();
 768   char tname[128];
 769   Printf("%s%s of size %zu at %p thread T%d%s%s\n",
 770          d.Access(),
 771          access_size ? (is_write ? "WRITE" : "READ") : "ACCESS",
 772          access_size, (void*)addr, curr_tid,
 773          ThreadNameWithParenthesis(curr_tid, tname, sizeof(tname)),
 774          d.EndAccess());
 775
 776   GET_STACK_TRACE_FATAL(pc, bp);
 777   PrintStack(&stack);
 778
 779   DescribeAddress(addr, access_size);
 780   ReportErrorSummary(bug_descr, &stack);
 781   PrintShadowMemoryForAddress(addr);
 782 }
 783
 784 void NOINLINE __asan_set_error_report_callback(void (*callback)(const char*)) {
 785   error_report_callback = callback;
 786   if (callback) {
 787     error_message_buffer_size = 1 << 16;
 788     error_message_buffer =
 789         (char*)MmapOrDie(error_message_buffer_size, __FUNCTION__);
 790     error_message_buffer_pos = 0;
 791   }
 792 }
 793
 794 void __asan_describe_address(uptr addr) {
 795   DescribeAddress(addr, 1);
 796 }
 797
 798 #if !SANITIZER_SUPPORTS_WEAK_HOOKS
 799 // Provide default implementation of __asan_on_error that does nothing
 800 // and may be overriden by user.
 801 SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE NOINLINE
 802 void __asan_on_error() {}
 803 #endif