asan_report.cc revision 60c9f441255211f17c4d355ead94392ba1841355 
1//===-- asan_report.cc ----------------------------------------------------===//
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// This file contains error reporting code.
13//===----------------------------------------------------------------------===//
14#include "asan_flags.h"
15#include "asan_internal.h"
16#include "asan_mapping.h"
17#include "asan_report.h"
18#include "asan_stack.h"
19#include "asan_thread.h"
20#include "asan_thread_registry.h"
21#include "sanitizer_common/sanitizer_common.h"
22#include "sanitizer_common/sanitizer_report_decorator.h"
23#include "sanitizer_common/sanitizer_symbolizer.h"
24
25namespace __asan {
26
27// -------------------- User-specified callbacks ----------------- {{{1
28static void (*error_report_callback)(const char*);
29static char *error_message_buffer = 0;
30static uptr error_message_buffer_pos = 0;
31static uptr error_message_buffer_size = 0;
32
33void AppendToErrorMessageBuffer(const char *buffer) {
34  if (error_message_buffer) {
35    uptr length = internal_strlen(buffer);
36    CHECK_GE(error_message_buffer_size, error_message_buffer_pos);
37    uptr remaining = error_message_buffer_size - error_message_buffer_pos;
38    internal_strncpy(error_message_buffer + error_message_buffer_pos,
39                     buffer, remaining);
40    error_message_buffer[error_message_buffer_size - 1] = '\0';
41    // FIXME: reallocate the buffer instead of truncating the message.
42    error_message_buffer_pos += remaining > length ? length : remaining;
43  }
44}
45
46// ---------------------- Decorator ------------------------------ {{{1
47bool PrintsToTtyCached() {
48  static int cached = 0;
49  static bool prints_to_tty;
50  if (!cached) {  // Ok wrt threads since we are printing only from one thread.
51    prints_to_tty = PrintsToTty();
52    cached = 1;
53  }
54  return prints_to_tty;
55}
56class Decorator: private __sanitizer::AnsiColorDecorator {
57 public:
58  Decorator() : __sanitizer::AnsiColorDecorator(PrintsToTtyCached()) { }
59  const char *Warning()    { return Red(); }
60  const char *EndWarning() { return Default(); }
61  const char *Access()     { return Blue(); }
62  const char *EndAccess()  { return Default(); }
63  const char *Location()   { return Green(); }
64  const char *EndLocation() { return Default(); }
65  const char *Allocation()  { return Magenta(); }
66  const char *EndAllocation()  { return Default(); }
67
68  const char *ShadowByte(u8 byte) {
69    switch (byte) {
70      case kAsanHeapLeftRedzoneMagic:
71      case kAsanHeapRightRedzoneMagic:
72        return Red();
73      case kAsanHeapFreeMagic:
74        return Magenta();
75      case kAsanStackLeftRedzoneMagic:
76      case kAsanStackMidRedzoneMagic:
77      case kAsanStackRightRedzoneMagic:
78      case kAsanStackPartialRedzoneMagic:
79        return Red();
80      case kAsanStackAfterReturnMagic:
81        return Magenta();
82      case kAsanInitializationOrderMagic:
83        return Cyan();
84      case kAsanUserPoisonedMemoryMagic:
85        return Blue();
86      case kAsanStackUseAfterScopeMagic:
87        return Magenta();
88      case kAsanGlobalRedzoneMagic:
89        return Red();
90      case kAsanInternalHeapMagic:
91        return Yellow();
92      default:
93        return Default();
94    }
95  }
96  const char *EndShadowByte() { return Default(); }
97};
98
99// ---------------------- Helper functions ----------------------- {{{1
100
101static void PrintShadowByte(const char *before, u8 byte,
102                            const char *after = "\n") {
103  Decorator d;
104  Printf("%s%s%x%x%s%s", before,
105         d.ShadowByte(byte), byte >> 4, byte & 15, d.EndShadowByte(), after);
106}
107
108static void PrintShadowBytes(const char *before, u8 *bytes,
109                             u8 *guilty, uptr n) {
110  Decorator d;
111  if (before)
112    Printf("%s%p:", before, bytes);
113  for (uptr i = 0; i < n; i++) {
114    u8 *p = bytes + i;
115    const char *before = p == guilty ? "[" :
116        p - 1 == guilty ? "" : " ";
117    const char *after = p == guilty ? "]" : "";
118    PrintShadowByte(before, *p, after);
119  }
120  Printf("\n");
121}
122
123static void PrintLegend() {
124  Printf("Shadow byte legend (one shadow byte represents %d "
125         "application bytes):\n", (int)SHADOW_GRANULARITY);
126  PrintShadowByte("  Addressable:           ", 0);
127  Printf("  Partially addressable: ");
128  for (uptr i = 1; i < SHADOW_GRANULARITY; i++)
129    PrintShadowByte("", i, " ");
130  Printf("\n");
131  PrintShadowByte("  Heap left redzone:     ", kAsanHeapLeftRedzoneMagic);
132  PrintShadowByte("  Heap righ redzone:     ", kAsanHeapRightRedzoneMagic);
133  PrintShadowByte("  Freed Heap region:     ", kAsanHeapFreeMagic);
134  PrintShadowByte("  Stack left redzone:    ", kAsanStackLeftRedzoneMagic);
135  PrintShadowByte("  Stack mid redzone:     ", kAsanStackMidRedzoneMagic);
136  PrintShadowByte("  Stack right redzone:   ", kAsanStackRightRedzoneMagic);
137  PrintShadowByte("  Stack partial redzone: ", kAsanStackPartialRedzoneMagic);
138  PrintShadowByte("  Stack after return:    ", kAsanStackAfterReturnMagic);
139  PrintShadowByte("  Stack use after scope: ", kAsanStackUseAfterScopeMagic);
140  PrintShadowByte("  Global redzone:        ", kAsanGlobalRedzoneMagic);
141  PrintShadowByte("  Global init order:     ", kAsanInitializationOrderMagic);
142  PrintShadowByte("  Poisoned by user:      ", kAsanUserPoisonedMemoryMagic);
143  PrintShadowByte("  ASan internal:         ", kAsanInternalHeapMagic);
144}
145
146static void PrintShadowMemoryForAddress(uptr addr) {
147  if (!AddrIsInMem(addr))
148    return;
149  uptr shadow_addr = MemToShadow(addr);
150  const uptr n_bytes_per_row = 16;
151  uptr aligned_shadow = shadow_addr & ~(n_bytes_per_row - 1);
152  Printf("Shadow bytes around the buggy address:\n");
153  for (int i = -5; i <= 5; i++) {
154    const char *prefix = (i == 0) ? "=>" : "  ";
155    PrintShadowBytes(prefix,
156                     (u8*)(aligned_shadow + i * n_bytes_per_row),
157                     (u8*)shadow_addr, n_bytes_per_row);
158  }
159  if (flags()->print_legend)
160    PrintLegend();
161}
162
163static void PrintZoneForPointer(uptr ptr, uptr zone_ptr,
164                                const char *zone_name) {
165  if (zone_ptr) {
166    if (zone_name) {
167      Printf("malloc_zone_from_ptr(%p) = %p, which is %s\n",
168                 ptr, zone_ptr, zone_name);
169    } else {
170      Printf("malloc_zone_from_ptr(%p) = %p, which doesn't have a name\n",
171                 ptr, zone_ptr);
172    }
173  } else {
174    Printf("malloc_zone_from_ptr(%p) = 0\n", ptr);
175  }
176}
177
178// ---------------------- Address Descriptions ------------------- {{{1
179
180static bool IsASCII(unsigned char c) {
181  return /*0x00 <= c &&*/ c <= 0x7F;
182}
183
184// Check if the global is a zero-terminated ASCII string. If so, print it.
185static void PrintGlobalNameIfASCII(const __asan_global &g) {
186  for (uptr p = g.beg; p < g.beg + g.size - 1; p++) {
187    if (!IsASCII(*(unsigned char*)p)) return;
188  }
189  if (*(char*)(g.beg + g.size - 1) != 0) return;
190  Printf("  '%s' is ascii string '%s'\n", g.name, (char*)g.beg);
191}
192
193bool DescribeAddressRelativeToGlobal(uptr addr, uptr size,
194                                     const __asan_global &g) {
195  static const uptr kMinimalDistanceFromAnotherGlobal = 64;
196  if (addr <= g.beg - kMinimalDistanceFromAnotherGlobal) return false;
197  if (addr >= g.beg + g.size_with_redzone) return false;
198  Decorator d;
199  Printf("%s", d.Location());
200  if (addr < g.beg) {
201    Printf("%p is located %zd bytes to the left", (void*)addr, g.beg - addr);
202  } else if (addr + size > g.beg + g.size) {
203    if (addr < g.beg + g.size)
204      addr = g.beg + g.size;
205    Printf("%p is located %zd bytes to the right", (void*)addr,
206           addr - (g.beg + g.size));
207  } else {
208    // Can it happen?
209    Printf("%p is located %zd bytes inside", (void*)addr, addr - g.beg);
210  }
211  Printf(" of global variable '%s' from '%s' (0x%zx) of size %zu\n",
212             g.name, g.module_name, g.beg, g.size);
213  Printf("%s", d.EndLocation());
214  PrintGlobalNameIfASCII(g);
215  return true;
216}
217
218bool DescribeAddressIfShadow(uptr addr) {
219  if (AddrIsInMem(addr))
220    return false;
221  static const char kAddrInShadowReport[] =
222      "Address %p is located in the %s.\n";
223  if (AddrIsInShadowGap(addr)) {
224    Printf(kAddrInShadowReport, addr, "shadow gap area");
225    return true;
226  }
227  if (AddrIsInHighShadow(addr)) {
228    Printf(kAddrInShadowReport, addr, "high shadow area");
229    return true;
230  }
231  if (AddrIsInLowShadow(addr)) {
232    Printf(kAddrInShadowReport, addr, "low shadow area");
233    return true;
234  }
235  CHECK(0 && "Address is not in memory and not in shadow?");
236  return false;
237}
238
239bool DescribeAddressIfStack(uptr addr, uptr access_size) {
240  AsanThread *t = asanThreadRegistry().FindThreadByStackAddress(addr);
241  if (!t) return false;
242  const sptr kBufSize = 4095;
243  char buf[kBufSize];
244  uptr offset = 0;
245  const char *frame_descr = t->GetFrameNameByAddr(addr, &offset);
246  // This string is created by the compiler and has the following form:
247  // "FunctioName n alloc_1 alloc_2 ... alloc_n"
248  // where alloc_i looks like "offset size len ObjectName ".
249  CHECK(frame_descr);
250  // Report the function name and the offset.
251  const char *name_end = internal_strchr(frame_descr, ' ');
252  CHECK(name_end);
253  buf[0] = 0;
254  internal_strncat(buf, frame_descr,
255                   Min(kBufSize,
256                       static_cast<sptr>(name_end - frame_descr)));
257  Decorator d;
258  Printf("%s", d.Location());
259  Printf("Address %p is located at offset %zu "
260             "in frame <%s> of T%d's stack:\n",
261             (void*)addr, offset, Demangle(buf), t->tid());
262  Printf("%s", d.EndLocation());
263  // Report the number of stack objects.
264  char *p;
265  uptr n_objects = internal_simple_strtoll(name_end, &p, 10);
266  CHECK(n_objects > 0);
267  Printf("  This frame has %zu object(s):\n", n_objects);
268  // Report all objects in this frame.
269  for (uptr i = 0; i < n_objects; i++) {
270    uptr beg, size;
271    sptr len;
272    beg  = internal_simple_strtoll(p, &p, 10);
273    size = internal_simple_strtoll(p, &p, 10);
274    len  = internal_simple_strtoll(p, &p, 10);
275    if (beg <= 0 || size <= 0 || len < 0 || *p != ' ') {
276      Printf("AddressSanitizer can't parse the stack frame "
277                 "descriptor: |%s|\n", frame_descr);
278      break;
279    }
280    p++;
281    buf[0] = 0;
282    internal_strncat(buf, p, Min(kBufSize, len));
283    p += len;
284    Printf("    [%zu, %zu) '%s'\n", beg, beg + size, buf);
285  }
286  Printf("HINT: this may be a false positive if your program uses "
287             "some custom stack unwind mechanism or swapcontext\n"
288             "      (longjmp and C++ exceptions *are* supported)\n");
289  DescribeThread(t->summary());
290  return true;
291}
292
293static void DescribeAccessToHeapChunk(AsanChunkView chunk, uptr addr,
294                                      uptr access_size) {
295  sptr offset;
296  Decorator d;
297  Printf("%s", d.Location());
298  if (chunk.AddrIsAtLeft(addr, access_size, &offset)) {
299    Printf("%p is located %zd bytes to the left of", (void*)addr, offset);
300  } else if (chunk.AddrIsAtRight(addr, access_size, &offset)) {
301    if (offset < 0) {
302      addr -= offset;
303      offset = 0;
304    }
305    Printf("%p is located %zd bytes to the right of", (void*)addr, offset);
306  } else if (chunk.AddrIsInside(addr, access_size, &offset)) {
307    Printf("%p is located %zd bytes inside of", (void*)addr, offset);
308  } else {
309    Printf("%p is located somewhere around (this is AddressSanitizer bug!)",
310           (void*)addr);
311  }
312  Printf(" %zu-byte region [%p,%p)\n", chunk.UsedSize(),
313         (void*)(chunk.Beg()), (void*)(chunk.End()));
314  Printf("%s", d.EndLocation());
315}
316
317// Return " (thread_name) " or an empty string if the name is empty.
318const char *ThreadNameWithParenthesis(AsanThreadSummary *t, char buff[],
319                                      uptr buff_len) {
320  const char *name = t->name();
321  if (*name == 0) return "";
322  buff[0] = 0;
323  internal_strncat(buff, " (", 3);
324  internal_strncat(buff, name, buff_len - 4);
325  internal_strncat(buff, ")", 2);
326  return buff;
327}
328
329const char *ThreadNameWithParenthesis(u32 tid, char buff[],
330                                      uptr buff_len) {
331  if (tid == kInvalidTid) return "";
332  AsanThreadSummary *t = asanThreadRegistry().FindByTid(tid);
333  return ThreadNameWithParenthesis(t, buff, buff_len);
334}
335
336void DescribeHeapAddress(uptr addr, uptr access_size) {
337  AsanChunkView chunk = FindHeapChunkByAddress(addr);
338  if (!chunk.IsValid()) return;
339  DescribeAccessToHeapChunk(chunk, addr, access_size);
340  CHECK(chunk.AllocTid() != kInvalidTid);
341  AsanThreadSummary *alloc_thread =
342      asanThreadRegistry().FindByTid(chunk.AllocTid());
343  StackTrace alloc_stack;
344  chunk.GetAllocStack(&alloc_stack);
345  AsanThread *t = asanThreadRegistry().GetCurrent();
346  CHECK(t);
347  char tname[128];
348  Decorator d;
349  if (chunk.FreeTid() != kInvalidTid) {
350    AsanThreadSummary *free_thread =
351        asanThreadRegistry().FindByTid(chunk.FreeTid());
352    Printf("%sfreed by thread T%d%s here:%s\n", d.Allocation(),
353           free_thread->tid(),
354           ThreadNameWithParenthesis(free_thread, tname, sizeof(tname)),
355           d.EndAllocation());
356    StackTrace free_stack;
357    chunk.GetFreeStack(&free_stack);
358    PrintStack(&free_stack);
359    Printf("%spreviously allocated by thread T%d%s here:%s\n",
360           d.Allocation(), alloc_thread->tid(),
361           ThreadNameWithParenthesis(alloc_thread, tname, sizeof(tname)),
362           d.EndAllocation());
363    PrintStack(&alloc_stack);
364    DescribeThread(t->summary());
365    DescribeThread(free_thread);
366    DescribeThread(alloc_thread);
367  } else {
368    Printf("%sallocated by thread T%d%s here:%s\n", d.Allocation(),
369           alloc_thread->tid(),
370           ThreadNameWithParenthesis(alloc_thread, tname, sizeof(tname)),
371           d.EndAllocation());
372    PrintStack(&alloc_stack);
373    DescribeThread(t->summary());
374    DescribeThread(alloc_thread);
375  }
376}
377
378void DescribeAddress(uptr addr, uptr access_size) {
379  // Check if this is shadow or shadow gap.
380  if (DescribeAddressIfShadow(addr))
381    return;
382  CHECK(AddrIsInMem(addr));
383  if (DescribeAddressIfGlobal(addr, access_size))
384    return;
385  if (DescribeAddressIfStack(addr, access_size))
386    return;
387  // Assume it is a heap address.
388  DescribeHeapAddress(addr, access_size);
389}
390
391// ------------------- Thread description -------------------- {{{1
392
393void DescribeThread(AsanThreadSummary *summary) {
394  CHECK(summary);
395  // No need to announce the main thread.
396  if (summary->tid() == 0 || summary->announced()) {
397    return;
398  }
399  summary->set_announced(true);
400  char tname[128];
401  Printf("Thread T%d%s", summary->tid(),
402         ThreadNameWithParenthesis(summary->tid(), tname, sizeof(tname)));
403  Printf(" created by T%d%s here:\n",
404         summary->parent_tid(),
405         ThreadNameWithParenthesis(summary->parent_tid(),
406                                   tname, sizeof(tname)));
407  PrintStack(summary->stack());
408  // Recursively described parent thread if needed.
409  if (flags()->print_full_thread_history) {
410    AsanThreadSummary *parent_summary =
411        asanThreadRegistry().FindByTid(summary->parent_tid());
412    DescribeThread(parent_summary);
413  }
414}
415
416// -------------------- Different kinds of reports ----------------- {{{1
417
418// Use ScopedInErrorReport to run common actions just before and
419// immediately after printing error report.
420class ScopedInErrorReport {
421 public:
422  ScopedInErrorReport() {
423    static atomic_uint32_t num_calls;
424    static u32 reporting_thread_tid;
425    if (atomic_fetch_add(&num_calls, 1, memory_order_relaxed) != 0) {
426      // Do not print more than one report, otherwise they will mix up.
427      // Error reporting functions shouldn't return at this situation, as
428      // they are defined as no-return.
429      Report("AddressSanitizer: while reporting a bug found another one."
430                 "Ignoring.\n");
431      u32 current_tid = asanThreadRegistry().GetCurrentTidOrInvalid();
432      if (current_tid != reporting_thread_tid) {
433        // ASan found two bugs in different threads simultaneously. Sleep
434        // long enough to make sure that the thread which started to print
435        // an error report will finish doing it.
436        SleepForSeconds(Max(100, flags()->sleep_before_dying + 1));
437      }
438      // If we're still not dead for some reason, use raw _exit() instead of
439      // Die() to bypass any additional checks.
440      internal__exit(flags()->exitcode);
441    }
442    ASAN_ON_ERROR();
443    reporting_thread_tid = asanThreadRegistry().GetCurrentTidOrInvalid();
444    Printf("===================================================="
445           "=============\n");
446    if (reporting_thread_tid != kInvalidTid) {
447      // We started reporting an error message. Stop using the fake stack
448      // in case we call an instrumented function from a symbolizer.
449      AsanThread *curr_thread = asanThreadRegistry().GetCurrent();
450      CHECK(curr_thread);
451      curr_thread->fake_stack().StopUsingFakeStack();
452    }
453  }
454  // Destructor is NORETURN, as functions that report errors are.
455  NORETURN ~ScopedInErrorReport() {
456    // Make sure the current thread is announced.
457    AsanThread *curr_thread = asanThreadRegistry().GetCurrent();
458    if (curr_thread) {
459      DescribeThread(curr_thread->summary());
460    }
461    // Print memory stats.
462    if (flags()->print_stats)
463      __asan_print_accumulated_stats();
464    if (error_report_callback) {
465      error_report_callback(error_message_buffer);
466    }
467    Report("ABORTING\n");
468    Die();
469  }
470};
471
472static void ReportSummary(const char *error_type, StackTrace *stack) {
473  if (!stack->size) return;
474  if (IsSymbolizerAvailable()) {
475    AddressInfo ai;
476    // Currently, we include the first stack frame into the report summary.
477    // Maybe sometimes we need to choose another frame (e.g. skip memcpy/etc).
478    SymbolizeCode(stack->trace[0], &ai, 1);
479    ReportErrorSummary(error_type,
480                       StripPathPrefix(ai.file, flags()->strip_path_prefix),
481                       ai.line, ai.function);
482  }
483  // FIXME: do we need to print anything at all if there is no symbolizer?
484}
485
486void ReportSIGSEGV(uptr pc, uptr sp, uptr bp, uptr addr) {
487  ScopedInErrorReport in_report;
488  Decorator d;
489  Printf("%s", d.Warning());
490  Report("ERROR: AddressSanitizer: SEGV on unknown address %p"
491             " (pc %p sp %p bp %p T%d)\n",
492             (void*)addr, (void*)pc, (void*)sp, (void*)bp,
493             asanThreadRegistry().GetCurrentTidOrInvalid());
494  Printf("%s", d.EndWarning());
495  Printf("AddressSanitizer can not provide additional info.\n");
496  GET_STACK_TRACE_FATAL(pc, bp);
497  PrintStack(&stack);
498  ReportSummary("SEGV", &stack);
499}
500
501void ReportDoubleFree(uptr addr, StackTrace *stack) {
502  ScopedInErrorReport in_report;
503  Decorator d;
504  Printf("%s", d.Warning());
505  Report("ERROR: AddressSanitizer: attempting double-free on %p:\n", addr);
506  Printf("%s", d.EndWarning());
507  PrintStack(stack);
508  DescribeHeapAddress(addr, 1);
509  ReportSummary("double-free", stack);
510}
511
512void ReportFreeNotMalloced(uptr addr, StackTrace *stack) {
513  ScopedInErrorReport in_report;
514  Decorator d;
515  Printf("%s", d.Warning());
516  Report("ERROR: AddressSanitizer: attempting free on address "
517             "which was not malloc()-ed: %p\n", addr);
518  Printf("%s", d.EndWarning());
519  PrintStack(stack);
520  DescribeHeapAddress(addr, 1);
521  ReportSummary("bad-free", stack);
522}
523
524void ReportAllocTypeMismatch(uptr addr, StackTrace *stack,
525                             AllocType alloc_type,
526                             AllocType dealloc_type) {
527  static const char *alloc_names[] =
528    {"INVALID", "malloc", "operator new", "operator new []"};
529  static const char *dealloc_names[] =
530    {"INVALID", "free", "operator delete", "operator delete []"};
531  CHECK_NE(alloc_type, dealloc_type);
532  ScopedInErrorReport in_report;
533  Decorator d;
534  Printf("%s", d.Warning());
535  Report("ERROR: AddressSanitizer: alloc-dealloc-mismatch (%s vs %s) on %p\n",
536        alloc_names[alloc_type], dealloc_names[dealloc_type], addr);
537  Printf("%s", d.EndWarning());
538  PrintStack(stack);
539  DescribeHeapAddress(addr, 1);
540  ReportSummary("alloc-dealloc-mismatch", stack);
541  Report("HINT: if you don't care about these warnings you may set "
542         "ASAN_OPTIONS=alloc_dealloc_mismatch=0\n");
543}
544
545void ReportMallocUsableSizeNotOwned(uptr addr, StackTrace *stack) {
546  ScopedInErrorReport in_report;
547  Decorator d;
548  Printf("%s", d.Warning());
549  Report("ERROR: AddressSanitizer: attempting to call "
550             "malloc_usable_size() for pointer which is "
551             "not owned: %p\n", addr);
552  Printf("%s", d.EndWarning());
553  PrintStack(stack);
554  DescribeHeapAddress(addr, 1);
555  ReportSummary("bad-malloc_usable_size", stack);
556}
557
558void ReportAsanGetAllocatedSizeNotOwned(uptr addr, StackTrace *stack) {
559  ScopedInErrorReport in_report;
560  Decorator d;
561  Printf("%s", d.Warning());
562  Report("ERROR: AddressSanitizer: attempting to call "
563             "__asan_get_allocated_size() for pointer which is "
564             "not owned: %p\n", addr);
565  Printf("%s", d.EndWarning());
566  PrintStack(stack);
567  DescribeHeapAddress(addr, 1);
568  ReportSummary("bad-__asan_get_allocated_size", stack);
569}
570
571void ReportStringFunctionMemoryRangesOverlap(
572    const char *function, const char *offset1, uptr length1,
573    const char *offset2, uptr length2, StackTrace *stack) {
574  ScopedInErrorReport in_report;
575  Decorator d;
576  char bug_type[100];
577  internal_snprintf(bug_type, sizeof(bug_type), "%s-param-overlap", function);
578  Printf("%s", d.Warning());
579  Report("ERROR: AddressSanitizer: %s: "
580             "memory ranges [%p,%p) and [%p, %p) overlap\n", \
581             bug_type, offset1, offset1 + length1, offset2, offset2 + length2);
582  Printf("%s", d.EndWarning());
583  PrintStack(stack);
584  DescribeAddress((uptr)offset1, length1);
585  DescribeAddress((uptr)offset2, length2);
586  ReportSummary(bug_type, stack);
587}
588
589// ----------------------- Mac-specific reports ----------------- {{{1
590
591void WarnMacFreeUnallocated(
592    uptr addr, uptr zone_ptr, const char *zone_name, StackTrace *stack) {
593  // Just print a warning here.
594  Printf("free_common(%p) -- attempting to free unallocated memory.\n"
595             "AddressSanitizer is ignoring this error on Mac OS now.\n",
596             addr);
597  PrintZoneForPointer(addr, zone_ptr, zone_name);
598  PrintStack(stack);
599  DescribeHeapAddress(addr, 1);
600}
601
602void ReportMacMzReallocUnknown(
603    uptr addr, uptr zone_ptr, const char *zone_name, StackTrace *stack) {
604  ScopedInErrorReport in_report;
605  Printf("mz_realloc(%p) -- attempting to realloc unallocated memory.\n"
606             "This is an unrecoverable problem, exiting now.\n",
607             addr);
608  PrintZoneForPointer(addr, zone_ptr, zone_name);
609  PrintStack(stack);
610  DescribeHeapAddress(addr, 1);
611}
612
613void ReportMacCfReallocUnknown(
614    uptr addr, uptr zone_ptr, const char *zone_name, StackTrace *stack) {
615  ScopedInErrorReport in_report;
616  Printf("cf_realloc(%p) -- attempting to realloc unallocated memory.\n"
617             "This is an unrecoverable problem, exiting now.\n",
618             addr);
619  PrintZoneForPointer(addr, zone_ptr, zone_name);
620  PrintStack(stack);
621  DescribeHeapAddress(addr, 1);
622}
623
624}  // namespace __asan
625
626// --------------------------- Interface --------------------- {{{1
627using namespace __asan;  // NOLINT
628
629void __asan_report_error(uptr pc, uptr bp, uptr sp,
630                         uptr addr, bool is_write, uptr access_size) {
631  ScopedInErrorReport in_report;
632
633  // Determine the error type.
634  const char *bug_descr = "unknown-crash";
635  if (AddrIsInMem(addr)) {
636    u8 *shadow_addr = (u8*)MemToShadow(addr);
637    // If we are accessing 16 bytes, look at the second shadow byte.
638    if (*shadow_addr == 0 && access_size > SHADOW_GRANULARITY)
639      shadow_addr++;
640    // If we are in the partial right redzone, look at the next shadow byte.
641    if (*shadow_addr > 0 && *shadow_addr < 128)
642      shadow_addr++;
643    switch (*shadow_addr) {
644      case kAsanHeapLeftRedzoneMagic:
645      case kAsanHeapRightRedzoneMagic:
646        bug_descr = "heap-buffer-overflow";
647        break;
648      case kAsanHeapFreeMagic:
649        bug_descr = "heap-use-after-free";
650        break;
651      case kAsanStackLeftRedzoneMagic:
652        bug_descr = "stack-buffer-underflow";
653        break;
654      case kAsanInitializationOrderMagic:
655        bug_descr = "initialization-order-fiasco";
656        break;
657      case kAsanStackMidRedzoneMagic:
658      case kAsanStackRightRedzoneMagic:
659      case kAsanStackPartialRedzoneMagic:
660        bug_descr = "stack-buffer-overflow";
661        break;
662      case kAsanStackAfterReturnMagic:
663        bug_descr = "stack-use-after-return";
664        break;
665      case kAsanUserPoisonedMemoryMagic:
666        bug_descr = "use-after-poison";
667        break;
668      case kAsanStackUseAfterScopeMagic:
669        bug_descr = "stack-use-after-scope";
670        break;
671      case kAsanGlobalRedzoneMagic:
672        bug_descr = "global-buffer-overflow";
673        break;
674    }
675  }
676  Decorator d;
677  Printf("%s", d.Warning());
678  Report("ERROR: AddressSanitizer: %s on address "
679             "%p at pc 0x%zx bp 0x%zx sp 0x%zx\n",
680             bug_descr, (void*)addr, pc, bp, sp);
681  Printf("%s", d.EndWarning());
682
683  u32 curr_tid = asanThreadRegistry().GetCurrentTidOrInvalid();
684  char tname[128];
685  Printf("%s%s of size %zu at %p thread T%d%s%s\n",
686         d.Access(),
687         access_size ? (is_write ? "WRITE" : "READ") : "ACCESS",
688         access_size, (void*)addr, curr_tid,
689         ThreadNameWithParenthesis(curr_tid, tname, sizeof(tname)),
690         d.EndAccess());
691
692  GET_STACK_TRACE_FATAL(pc, bp);
693  PrintStack(&stack);
694
695  DescribeAddress(addr, access_size);
696  ReportSummary(bug_descr, &stack);
697  PrintShadowMemoryForAddress(addr);
698}
699
700void NOINLINE __asan_set_error_report_callback(void (*callback)(const char*)) {
701  error_report_callback = callback;
702  if (callback) {
703    error_message_buffer_size = 1 << 16;
704    error_message_buffer =
705        (char*)MmapOrDie(error_message_buffer_size, __FUNCTION__);
706    error_message_buffer_pos = 0;
707  }
708}
709
710void __asan_describe_address(uptr addr) {
711  DescribeAddress(addr, 1);
712}
713
714#if !SANITIZER_SUPPORTS_WEAK_HOOKS
715// Provide default implementation of __asan_on_error that does nothing
716// and may be overriden by user.
717SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE NOINLINE
718void __asan_on_error() {}
719#endif
720