asan_report.cc revision 997454a41a1658837d72d69ec7def59616311243 
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 "sanitizer_common/sanitizer_common.h"
21#include "sanitizer_common/sanitizer_flags.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
47class Decorator: private __sanitizer::AnsiColorDecorator {
48 public:
49  Decorator() : __sanitizer::AnsiColorDecorator(PrintsToTtyCached()) { }
50  const char *Warning()    { return Red(); }
51  const char *EndWarning() { return Default(); }
52  const char *Access()     { return Blue(); }
53  const char *EndAccess()  { return Default(); }
54  const char *Location()   { return Green(); }
55  const char *EndLocation() { return Default(); }
56  const char *Allocation()  { return Magenta(); }
57  const char *EndAllocation()  { return Default(); }
58
59  const char *ShadowByte(u8 byte) {
60    switch (byte) {
61      case kAsanHeapLeftRedzoneMagic:
62      case kAsanHeapRightRedzoneMagic:
63        return Red();
64      case kAsanHeapFreeMagic:
65        return Magenta();
66      case kAsanStackLeftRedzoneMagic:
67      case kAsanStackMidRedzoneMagic:
68      case kAsanStackRightRedzoneMagic:
69      case kAsanStackPartialRedzoneMagic:
70        return Red();
71      case kAsanStackAfterReturnMagic:
72        return Magenta();
73      case kAsanInitializationOrderMagic:
74        return Cyan();
75      case kAsanUserPoisonedMemoryMagic:
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
92static 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
99static 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
114static 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("  ASan internal:         ", kAsanInternalHeapMagic);
135}
136
137static void PrintShadowMemoryForAddress(uptr addr) {
138  if (!AddrIsInMem(addr))
139    return;
140  uptr shadow_addr = MemToShadow(addr);
141  const uptr n_bytes_per_row = 16;
142  uptr aligned_shadow = shadow_addr & ~(n_bytes_per_row - 1);
143  Printf("Shadow bytes around the buggy address:\n");
144  for (int i = -5; i <= 5; i++) {
145    const char *prefix = (i == 0) ? "=>" : "  ";
146    PrintShadowBytes(prefix,
147                     (u8*)(aligned_shadow + i * n_bytes_per_row),
148                     (u8*)shadow_addr, n_bytes_per_row);
149  }
150  if (flags()->print_legend)
151    PrintLegend();
152}
153
154static void PrintZoneForPointer(uptr ptr, uptr zone_ptr,
155                                const char *zone_name) {
156  if (zone_ptr) {
157    if (zone_name) {
158      Printf("malloc_zone_from_ptr(%p) = %p, which is %s\n",
159                 ptr, zone_ptr, zone_name);
160    } else {
161      Printf("malloc_zone_from_ptr(%p) = %p, which doesn't have a name\n",
162                 ptr, zone_ptr);
163    }
164  } else {
165    Printf("malloc_zone_from_ptr(%p) = 0\n", ptr);
166  }
167}
168
169static void DescribeThread(AsanThread *t) {
170  if (t)
171    DescribeThread(t->context());
172}
173
174// ---------------------- Address Descriptions ------------------- {{{1
175
176static bool IsASCII(unsigned char c) {
177  return /*0x00 <= c &&*/ c <= 0x7F;
178}
179
180static const char *MaybeDemangleGlobalName(const char *name) {
181  // We can spoil names of globals with C linkage, so use an heuristic
182  // approach to check if the name should be demangled.
183  return (name[0] == '_' && name[1] == 'Z') ? Demangle(name) : name;
184}
185
186// Check if the global is a zero-terminated ASCII string. If so, print it.
187static void PrintGlobalNameIfASCII(const __asan_global &g) {
188  for (uptr p = g.beg; p < g.beg + g.size - 1; p++) {
189    unsigned char c = *(unsigned char*)p;
190    if (c == '\0' || !IsASCII(c)) return;
191  }
192  if (*(char*)(g.beg + g.size - 1) != '\0') return;
193  Printf("  '%s' is ascii string '%s'\n",
194         MaybeDemangleGlobalName(g.name), (char*)g.beg);
195}
196
197bool DescribeAddressRelativeToGlobal(uptr addr, uptr size,
198                                     const __asan_global &g) {
199  static const uptr kMinimalDistanceFromAnotherGlobal = 64;
200  if (addr <= g.beg - kMinimalDistanceFromAnotherGlobal) return false;
201  if (addr >= g.beg + g.size_with_redzone) return false;
202  Decorator d;
203  Printf("%s", d.Location());
204  if (addr < g.beg) {
205    Printf("%p is located %zd bytes to the left", (void*)addr, g.beg - addr);
206  } else if (addr + size > g.beg + g.size) {
207    if (addr < g.beg + g.size)
208      addr = g.beg + g.size;
209    Printf("%p is located %zd bytes to the right", (void*)addr,
210           addr - (g.beg + g.size));
211  } else {
212    // Can it happen?
213    Printf("%p is located %zd bytes inside", (void*)addr, addr - g.beg);
214  }
215  Printf(" of global variable '%s' from '%s' (0x%zx) of size %zu\n",
216             MaybeDemangleGlobalName(g.name), g.module_name, g.beg, g.size);
217  Printf("%s", d.EndLocation());
218  PrintGlobalNameIfASCII(g);
219  return true;
220}
221
222bool DescribeAddressIfShadow(uptr addr) {
223  if (AddrIsInMem(addr))
224    return false;
225  static const char kAddrInShadowReport[] =
226      "Address %p is located in the %s.\n";
227  if (AddrIsInShadowGap(addr)) {
228    Printf(kAddrInShadowReport, addr, "shadow gap area");
229    return true;
230  }
231  if (AddrIsInHighShadow(addr)) {
232    Printf(kAddrInShadowReport, addr, "high shadow area");
233    return true;
234  }
235  if (AddrIsInLowShadow(addr)) {
236    Printf(kAddrInShadowReport, addr, "low shadow area");
237    return true;
238  }
239  CHECK(0 && "Address is not in memory and not in shadow?");
240  return false;
241}
242
243// Return " (thread_name) " or an empty string if the name is empty.
244const char *ThreadNameWithParenthesis(AsanThreadContext *t, char buff[],
245                                      uptr buff_len) {
246  const char *name = t->name;
247  if (name[0] == '\0') return "";
248  buff[0] = 0;
249  internal_strncat(buff, " (", 3);
250  internal_strncat(buff, name, buff_len - 4);
251  internal_strncat(buff, ")", 2);
252  return buff;
253}
254
255const char *ThreadNameWithParenthesis(u32 tid, char buff[],
256                                      uptr buff_len) {
257  if (tid == kInvalidTid) return "";
258  asanThreadRegistry().CheckLocked();
259  AsanThreadContext *t = GetThreadContextByTidLocked(tid);
260  return ThreadNameWithParenthesis(t, buff, buff_len);
261}
262
263void PrintAccessAndVarIntersection(const char *var_name,
264                                   uptr var_beg, uptr var_size,
265                                   uptr addr, uptr access_size,
266                                   uptr prev_var_end, uptr next_var_beg) {
267  uptr var_end = var_beg + var_size;
268  uptr addr_end = addr + access_size;
269  const char *pos_descr = 0;
270  // If the variable [var_beg, var_end) is the nearest variable to the
271  // current memory access, indicate it in the log.
272  if (addr >= var_beg) {
273    if (addr_end <= var_end)
274      pos_descr = "is inside";  // May happen if this is a use-after-return.
275    else if (addr < var_end)
276      pos_descr = "partially overflows";
277    else if (addr_end <= next_var_beg &&
278             next_var_beg - addr_end >= addr - var_end)
279      pos_descr = "overflows";
280  } else {
281    if (addr_end > var_beg)
282      pos_descr = "partially underflows";
283    else if (addr >= prev_var_end &&
284             addr - prev_var_end >= var_beg - addr_end)
285      pos_descr = "underflows";
286  }
287  Printf("    [%zd, %zd) '%s'", var_beg, var_beg + var_size, var_name);
288  if (pos_descr) {
289    Decorator d;
290    // FIXME: we may want to also print the size of the access here,
291    // but in case of accesses generated by memset it may be confusing.
292    Printf("%s <== Memory access at offset %zd %s this variable%s\n",
293           d.Location(), addr, pos_descr, d.EndLocation());
294  } else {
295    Printf("\n");
296  }
297}
298
299struct StackVarDescr {
300  uptr beg;
301  uptr size;
302  const char *name_pos;
303  uptr name_len;
304};
305
306bool DescribeAddressIfStack(uptr addr, uptr access_size) {
307  AsanThread *t = FindThreadByStackAddress(addr);
308  if (!t) return false;
309  const uptr kBufSize = 4095;
310  char buf[kBufSize];
311  uptr offset = 0;
312  uptr frame_pc = 0;
313  char tname[128];
314  const char *frame_descr = t->GetFrameNameByAddr(addr, &offset, &frame_pc);
315
316#ifdef __powerpc64__
317  // On PowerPC64, the address of a function actually points to a
318  // three-doubleword data structure with the first field containing
319  // the address of the function's code.
320  frame_pc = *reinterpret_cast<uptr *>(frame_pc);
321#endif
322
323  // This string is created by the compiler and has the following form:
324  // "n alloc_1 alloc_2 ... alloc_n"
325  // where alloc_i looks like "offset size len ObjectName ".
326  CHECK(frame_descr);
327  Decorator d;
328  Printf("%s", d.Location());
329  Printf("Address %p is located in stack of thread T%d%s "
330         "at offset %zu in frame\n",
331         addr, t->tid(),
332         ThreadNameWithParenthesis(t->tid(), tname, sizeof(tname)),
333         offset);
334  // Now we print the frame where the alloca has happened.
335  // We print this frame as a stack trace with one element.
336  // The symbolizer may print more than one frame if inlining was involved.
337  // The frame numbers may be different than those in the stack trace printed
338  // previously. That's unfortunate, but I have no better solution,
339  // especially given that the alloca may be from entirely different place
340  // (e.g. use-after-scope, or different thread's stack).
341  StackTrace alloca_stack;
342  alloca_stack.trace[0] = frame_pc + 16;
343  alloca_stack.size = 1;
344  Printf("%s", d.EndLocation());
345  PrintStack(&alloca_stack);
346  // Report the number of stack objects.
347  char *p;
348  uptr n_objects = (uptr)internal_simple_strtoll(frame_descr, &p, 10);
349  CHECK_GT(n_objects, 0);
350  Printf("  This frame has %zu object(s):\n", n_objects);
351
352  // Report all objects in this frame.
353  InternalScopedBuffer<StackVarDescr> vars(n_objects);
354  for (uptr i = 0; i < n_objects; i++) {
355    uptr beg, size;
356    uptr len;
357    beg  = (uptr)internal_simple_strtoll(p, &p, 10);
358    size = (uptr)internal_simple_strtoll(p, &p, 10);
359    len  = (uptr)internal_simple_strtoll(p, &p, 10);
360    if (beg == 0 || size == 0 || *p != ' ') {
361      Printf("AddressSanitizer can't parse the stack frame "
362                 "descriptor: |%s|\n", frame_descr);
363      break;
364    }
365    p++;
366    vars[i].beg = beg;
367    vars[i].size = size;
368    vars[i].name_pos = p;
369    vars[i].name_len = len;
370    p += len;
371  }
372  for (uptr i = 0; i < n_objects; i++) {
373    buf[0] = 0;
374    internal_strncat(buf, vars[i].name_pos,
375                     static_cast<uptr>(Min(kBufSize, vars[i].name_len)));
376    uptr prev_var_end = i ? vars[i - 1].beg + vars[i - 1].size : 0;
377    uptr next_var_beg = i + 1 < n_objects ? vars[i + 1].beg : ~(0UL);
378    PrintAccessAndVarIntersection(buf, vars[i].beg, vars[i].size,
379                                  offset, access_size,
380                                  prev_var_end, next_var_beg);
381  }
382  Printf("HINT: this may be a false positive if your program uses "
383             "some custom stack unwind mechanism or swapcontext\n"
384             "      (longjmp and C++ exceptions *are* supported)\n");
385  DescribeThread(t);
386  return true;
387}
388
389static void DescribeAccessToHeapChunk(AsanChunkView chunk, uptr addr,
390                                      uptr access_size) {
391  sptr offset;
392  Decorator d;
393  Printf("%s", d.Location());
394  if (chunk.AddrIsAtLeft(addr, access_size, &offset)) {
395    Printf("%p is located %zd bytes to the left of", (void*)addr, offset);
396  } else if (chunk.AddrIsAtRight(addr, access_size, &offset)) {
397    if (offset < 0) {
398      addr -= offset;
399      offset = 0;
400    }
401    Printf("%p is located %zd bytes to the right of", (void*)addr, offset);
402  } else if (chunk.AddrIsInside(addr, access_size, &offset)) {
403    Printf("%p is located %zd bytes inside of", (void*)addr, offset);
404  } else {
405    Printf("%p is located somewhere around (this is AddressSanitizer bug!)",
406           (void*)addr);
407  }
408  Printf(" %zu-byte region [%p,%p)\n", chunk.UsedSize(),
409         (void*)(chunk.Beg()), (void*)(chunk.End()));
410  Printf("%s", d.EndLocation());
411}
412
413void DescribeHeapAddress(uptr addr, uptr access_size) {
414  AsanChunkView chunk = FindHeapChunkByAddress(addr);
415  if (!chunk.IsValid()) return;
416  DescribeAccessToHeapChunk(chunk, addr, access_size);
417  CHECK(chunk.AllocTid() != kInvalidTid);
418  asanThreadRegistry().CheckLocked();
419  AsanThreadContext *alloc_thread =
420      GetThreadContextByTidLocked(chunk.AllocTid());
421  StackTrace alloc_stack;
422  chunk.GetAllocStack(&alloc_stack);
423  char tname[128];
424  Decorator d;
425  AsanThreadContext *free_thread = 0;
426  if (chunk.FreeTid() != kInvalidTid) {
427    free_thread = GetThreadContextByTidLocked(chunk.FreeTid());
428    Printf("%sfreed by thread T%d%s here:%s\n", d.Allocation(),
429           free_thread->tid,
430           ThreadNameWithParenthesis(free_thread, tname, sizeof(tname)),
431           d.EndAllocation());
432    StackTrace free_stack;
433    chunk.GetFreeStack(&free_stack);
434    PrintStack(&free_stack);
435    Printf("%spreviously allocated by thread T%d%s here:%s\n",
436           d.Allocation(), alloc_thread->tid,
437           ThreadNameWithParenthesis(alloc_thread, tname, sizeof(tname)),
438           d.EndAllocation());
439  } else {
440    Printf("%sallocated by thread T%d%s here:%s\n", d.Allocation(),
441           alloc_thread->tid,
442           ThreadNameWithParenthesis(alloc_thread, tname, sizeof(tname)),
443           d.EndAllocation());
444  }
445  PrintStack(&alloc_stack);
446  DescribeThread(GetCurrentThread());
447  if (free_thread)
448    DescribeThread(free_thread);
449  DescribeThread(alloc_thread);
450}
451
452void DescribeAddress(uptr addr, uptr access_size) {
453  // Check if this is shadow or shadow gap.
454  if (DescribeAddressIfShadow(addr))
455    return;
456  CHECK(AddrIsInMem(addr));
457  if (DescribeAddressIfGlobal(addr, access_size))
458    return;
459  if (DescribeAddressIfStack(addr, access_size))
460    return;
461  // Assume it is a heap address.
462  DescribeHeapAddress(addr, access_size);
463}
464
465// ------------------- Thread description -------------------- {{{1
466
467void DescribeThread(AsanThreadContext *context) {
468  CHECK(context);
469  asanThreadRegistry().CheckLocked();
470  // No need to announce the main thread.
471  if (context->tid == 0 || context->announced) {
472    return;
473  }
474  context->announced = true;
475  char tname[128];
476  Printf("Thread T%d%s", context->tid,
477         ThreadNameWithParenthesis(context->tid, tname, sizeof(tname)));
478  Printf(" created by T%d%s here:\n",
479         context->parent_tid,
480         ThreadNameWithParenthesis(context->parent_tid,
481                                   tname, sizeof(tname)));
482  PrintStack(&context->stack);
483  // Recursively described parent thread if needed.
484  if (flags()->print_full_thread_history) {
485    AsanThreadContext *parent_context =
486        GetThreadContextByTidLocked(context->parent_tid);
487    DescribeThread(parent_context);
488  }
489}
490
491// -------------------- Different kinds of reports ----------------- {{{1
492
493// Use ScopedInErrorReport to run common actions just before and
494// immediately after printing error report.
495class ScopedInErrorReport {
496 public:
497  ScopedInErrorReport() {
498    static atomic_uint32_t num_calls;
499    static u32 reporting_thread_tid;
500    if (atomic_fetch_add(&num_calls, 1, memory_order_relaxed) != 0) {
501      // Do not print more than one report, otherwise they will mix up.
502      // Error reporting functions shouldn't return at this situation, as
503      // they are defined as no-return.
504      Report("AddressSanitizer: while reporting a bug found another one."
505                 "Ignoring.\n");
506      u32 current_tid = GetCurrentTidOrInvalid();
507      if (current_tid != reporting_thread_tid) {
508        // ASan found two bugs in different threads simultaneously. Sleep
509        // long enough to make sure that the thread which started to print
510        // an error report will finish doing it.
511        SleepForSeconds(Max(100, flags()->sleep_before_dying + 1));
512      }
513      // If we're still not dead for some reason, use raw _exit() instead of
514      // Die() to bypass any additional checks.
515      internal__exit(flags()->exitcode);
516    }
517    ASAN_ON_ERROR();
518    // Make sure the registry and sanitizer report mutexes are locked while
519    // we're printing an error report.
520    // We can lock them only here to avoid self-deadlock in case of
521    // recursive reports.
522    asanThreadRegistry().Lock();
523    CommonSanitizerReportMutex.Lock();
524    reporting_thread_tid = GetCurrentTidOrInvalid();
525    Printf("===================================================="
526           "=============\n");
527    if (reporting_thread_tid != kInvalidTid) {
528      // We started reporting an error message. Stop using the fake stack
529      // in case we call an instrumented function from a symbolizer.
530      AsanThread *curr_thread = GetCurrentThread();
531      CHECK(curr_thread);
532      if (curr_thread->fake_stack())
533        curr_thread->fake_stack()->StopUsingFakeStack();
534    }
535  }
536  // Destructor is NORETURN, as functions that report errors are.
537  NORETURN ~ScopedInErrorReport() {
538    // Make sure the current thread is announced.
539    DescribeThread(GetCurrentThread());
540    // Print memory stats.
541    if (flags()->print_stats)
542      __asan_print_accumulated_stats();
543    if (error_report_callback) {
544      error_report_callback(error_message_buffer);
545    }
546    Report("ABORTING\n");
547    Die();
548  }
549};
550
551static void ReportSummary(const char *error_type, StackTrace *stack) {
552  if (!stack->size) return;
553  if (IsSymbolizerAvailable()) {
554    AddressInfo ai;
555    // Currently, we include the first stack frame into the report summary.
556    // Maybe sometimes we need to choose another frame (e.g. skip memcpy/etc).
557    uptr pc = StackTrace::GetPreviousInstructionPc(stack->trace[0]);
558    SymbolizeCode(pc, &ai, 1);
559    ReportErrorSummary(error_type,
560                       StripPathPrefix(ai.file,
561                                       common_flags()->strip_path_prefix),
562                       ai.line, ai.function);
563  }
564  // FIXME: do we need to print anything at all if there is no symbolizer?
565}
566
567void ReportSIGSEGV(uptr pc, uptr sp, uptr bp, uptr addr) {
568  ScopedInErrorReport in_report;
569  Decorator d;
570  Printf("%s", d.Warning());
571  Report("ERROR: AddressSanitizer: SEGV on unknown address %p"
572             " (pc %p sp %p bp %p T%d)\n",
573             (void*)addr, (void*)pc, (void*)sp, (void*)bp,
574             GetCurrentTidOrInvalid());
575  Printf("%s", d.EndWarning());
576  Printf("AddressSanitizer can not provide additional info.\n");
577  GET_STACK_TRACE_FATAL(pc, bp);
578  PrintStack(&stack);
579  ReportSummary("SEGV", &stack);
580}
581
582void ReportDoubleFree(uptr addr, StackTrace *stack) {
583  ScopedInErrorReport in_report;
584  Decorator d;
585  Printf("%s", d.Warning());
586  char tname[128];
587  u32 curr_tid = GetCurrentTidOrInvalid();
588  Report("ERROR: AddressSanitizer: attempting double-free on %p in "
589         "thread T%d%s:\n",
590         addr, curr_tid,
591         ThreadNameWithParenthesis(curr_tid, tname, sizeof(tname)));
592
593  Printf("%s", d.EndWarning());
594  PrintStack(stack);
595  DescribeHeapAddress(addr, 1);
596  ReportSummary("double-free", stack);
597}
598
599void ReportFreeNotMalloced(uptr addr, StackTrace *stack) {
600  ScopedInErrorReport in_report;
601  Decorator d;
602  Printf("%s", d.Warning());
603  char tname[128];
604  u32 curr_tid = GetCurrentTidOrInvalid();
605  Report("ERROR: AddressSanitizer: attempting free on address "
606             "which was not malloc()-ed: %p in thread T%d%s\n", addr,
607         curr_tid, ThreadNameWithParenthesis(curr_tid, tname, sizeof(tname)));
608  Printf("%s", d.EndWarning());
609  PrintStack(stack);
610  DescribeHeapAddress(addr, 1);
611  ReportSummary("bad-free", stack);
612}
613
614void ReportAllocTypeMismatch(uptr addr, StackTrace *stack,
615                             AllocType alloc_type,
616                             AllocType dealloc_type) {
617  static const char *alloc_names[] =
618    {"INVALID", "malloc", "operator new", "operator new []"};
619  static const char *dealloc_names[] =
620    {"INVALID", "free", "operator delete", "operator delete []"};
621  CHECK_NE(alloc_type, dealloc_type);
622  ScopedInErrorReport in_report;
623  Decorator d;
624  Printf("%s", d.Warning());
625  Report("ERROR: AddressSanitizer: alloc-dealloc-mismatch (%s vs %s) on %p\n",
626        alloc_names[alloc_type], dealloc_names[dealloc_type], addr);
627  Printf("%s", d.EndWarning());
628  PrintStack(stack);
629  DescribeHeapAddress(addr, 1);
630  ReportSummary("alloc-dealloc-mismatch", stack);
631  Report("HINT: if you don't care about these warnings you may set "
632         "ASAN_OPTIONS=alloc_dealloc_mismatch=0\n");
633}
634
635void ReportMallocUsableSizeNotOwned(uptr addr, StackTrace *stack) {
636  ScopedInErrorReport in_report;
637  Decorator d;
638  Printf("%s", d.Warning());
639  Report("ERROR: AddressSanitizer: attempting to call "
640             "malloc_usable_size() for pointer which is "
641             "not owned: %p\n", addr);
642  Printf("%s", d.EndWarning());
643  PrintStack(stack);
644  DescribeHeapAddress(addr, 1);
645  ReportSummary("bad-malloc_usable_size", stack);
646}
647
648void ReportAsanGetAllocatedSizeNotOwned(uptr addr, StackTrace *stack) {
649  ScopedInErrorReport in_report;
650  Decorator d;
651  Printf("%s", d.Warning());
652  Report("ERROR: AddressSanitizer: attempting to call "
653             "__asan_get_allocated_size() for pointer which is "
654             "not owned: %p\n", addr);
655  Printf("%s", d.EndWarning());
656  PrintStack(stack);
657  DescribeHeapAddress(addr, 1);
658  ReportSummary("bad-__asan_get_allocated_size", stack);
659}
660
661void ReportStringFunctionMemoryRangesOverlap(
662    const char *function, const char *offset1, uptr length1,
663    const char *offset2, uptr length2, StackTrace *stack) {
664  ScopedInErrorReport in_report;
665  Decorator d;
666  char bug_type[100];
667  internal_snprintf(bug_type, sizeof(bug_type), "%s-param-overlap", function);
668  Printf("%s", d.Warning());
669  Report("ERROR: AddressSanitizer: %s: "
670             "memory ranges [%p,%p) and [%p, %p) overlap\n", \
671             bug_type, offset1, offset1 + length1, offset2, offset2 + length2);
672  Printf("%s", d.EndWarning());
673  PrintStack(stack);
674  DescribeAddress((uptr)offset1, length1);
675  DescribeAddress((uptr)offset2, length2);
676  ReportSummary(bug_type, stack);
677}
678
679// ----------------------- Mac-specific reports ----------------- {{{1
680
681void WarnMacFreeUnallocated(
682    uptr addr, uptr zone_ptr, const char *zone_name, StackTrace *stack) {
683  // Just print a warning here.
684  Printf("free_common(%p) -- attempting to free unallocated memory.\n"
685             "AddressSanitizer is ignoring this error on Mac OS now.\n",
686             addr);
687  PrintZoneForPointer(addr, zone_ptr, zone_name);
688  PrintStack(stack);
689  DescribeHeapAddress(addr, 1);
690}
691
692void ReportMacMzReallocUnknown(
693    uptr addr, uptr zone_ptr, const char *zone_name, StackTrace *stack) {
694  ScopedInErrorReport in_report;
695  Printf("mz_realloc(%p) -- attempting to realloc unallocated memory.\n"
696             "This is an unrecoverable problem, exiting now.\n",
697             addr);
698  PrintZoneForPointer(addr, zone_ptr, zone_name);
699  PrintStack(stack);
700  DescribeHeapAddress(addr, 1);
701}
702
703void ReportMacCfReallocUnknown(
704    uptr addr, uptr zone_ptr, const char *zone_name, StackTrace *stack) {
705  ScopedInErrorReport in_report;
706  Printf("cf_realloc(%p) -- attempting to realloc unallocated memory.\n"
707             "This is an unrecoverable problem, exiting now.\n",
708             addr);
709  PrintZoneForPointer(addr, zone_ptr, zone_name);
710  PrintStack(stack);
711  DescribeHeapAddress(addr, 1);
712}
713
714}  // namespace __asan
715
716// --------------------------- Interface --------------------- {{{1
717using namespace __asan;  // NOLINT
718
719void __asan_report_error(uptr pc, uptr bp, uptr sp,
720                         uptr addr, bool is_write, uptr access_size) {
721  ScopedInErrorReport in_report;
722
723  // Determine the error type.
724  const char *bug_descr = "unknown-crash";
725  if (AddrIsInMem(addr)) {
726    u8 *shadow_addr = (u8*)MemToShadow(addr);
727    // If we are accessing 16 bytes, look at the second shadow byte.
728    if (*shadow_addr == 0 && access_size > SHADOW_GRANULARITY)
729      shadow_addr++;
730    // If we are in the partial right redzone, look at the next shadow byte.
731    if (*shadow_addr > 0 && *shadow_addr < 128)
732      shadow_addr++;
733    switch (*shadow_addr) {
734      case kAsanHeapLeftRedzoneMagic:
735      case kAsanHeapRightRedzoneMagic:
736        bug_descr = "heap-buffer-overflow";
737        break;
738      case kAsanHeapFreeMagic:
739        bug_descr = "heap-use-after-free";
740        break;
741      case kAsanStackLeftRedzoneMagic:
742        bug_descr = "stack-buffer-underflow";
743        break;
744      case kAsanInitializationOrderMagic:
745        bug_descr = "initialization-order-fiasco";
746        break;
747      case kAsanStackMidRedzoneMagic:
748      case kAsanStackRightRedzoneMagic:
749      case kAsanStackPartialRedzoneMagic:
750        bug_descr = "stack-buffer-overflow";
751        break;
752      case kAsanStackAfterReturnMagic:
753        bug_descr = "stack-use-after-return";
754        break;
755      case kAsanUserPoisonedMemoryMagic:
756        bug_descr = "use-after-poison";
757        break;
758      case kAsanStackUseAfterScopeMagic:
759        bug_descr = "stack-use-after-scope";
760        break;
761      case kAsanGlobalRedzoneMagic:
762        bug_descr = "global-buffer-overflow";
763        break;
764    }
765  }
766  Decorator d;
767  Printf("%s", d.Warning());
768  Report("ERROR: AddressSanitizer: %s on address "
769             "%p at pc 0x%zx bp 0x%zx sp 0x%zx\n",
770             bug_descr, (void*)addr, pc, bp, sp);
771  Printf("%s", d.EndWarning());
772
773  u32 curr_tid = GetCurrentTidOrInvalid();
774  char tname[128];
775  Printf("%s%s of size %zu at %p thread T%d%s%s\n",
776         d.Access(),
777         access_size ? (is_write ? "WRITE" : "READ") : "ACCESS",
778         access_size, (void*)addr, curr_tid,
779         ThreadNameWithParenthesis(curr_tid, tname, sizeof(tname)),
780         d.EndAccess());
781
782  GET_STACK_TRACE_FATAL(pc, bp);
783  PrintStack(&stack);
784
785  DescribeAddress(addr, access_size);
786  ReportSummary(bug_descr, &stack);
787  PrintShadowMemoryForAddress(addr);
788}
789
790void NOINLINE __asan_set_error_report_callback(void (*callback)(const char*)) {
791  error_report_callback = callback;
792  if (callback) {
793    error_message_buffer_size = 1 << 16;
794    error_message_buffer =
795        (char*)MmapOrDie(error_message_buffer_size, __FUNCTION__);
796    error_message_buffer_pos = 0;
797  }
798}
799
800void __asan_describe_address(uptr addr) {
801  DescribeAddress(addr, 1);
802}
803
804#if !SANITIZER_SUPPORTS_WEAK_HOOKS
805// Provide default implementation of __asan_on_error that does nothing
806// and may be overriden by user.
807SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE NOINLINE
808void __asan_on_error() {}
809#endif
810