xref: /freebsd/contrib/llvm-project/compiler-rt/lib/tsan/rtl/tsan_report.cpp (revision 1db9f3b21e39176dd5b67cf8ac378633b172463e)
1 //===-- tsan_report.cpp ---------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file is a part of ThreadSanitizer (TSan), a race detector.
10 //
11 //===----------------------------------------------------------------------===//
12 #include "tsan_report.h"
13 #include "tsan_platform.h"
14 #include "tsan_rtl.h"
15 #include "sanitizer_common/sanitizer_file.h"
16 #include "sanitizer_common/sanitizer_placement_new.h"
17 #include "sanitizer_common/sanitizer_report_decorator.h"
18 #include "sanitizer_common/sanitizer_stacktrace_printer.h"
19 
20 namespace __tsan {
21 
22 class Decorator: public __sanitizer::SanitizerCommonDecorator {
23  public:
24   Decorator() : SanitizerCommonDecorator() { }
25   const char *Access()     { return Blue(); }
26   const char *ThreadDescription()    { return Cyan(); }
27   const char *Location()   { return Green(); }
28   const char *Sleep()   { return Yellow(); }
29   const char *Mutex()   { return Magenta(); }
30 };
31 
32 ReportDesc::ReportDesc()
33     : tag(kExternalTagNone)
34     , stacks()
35     , mops()
36     , locs()
37     , mutexes()
38     , threads()
39     , unique_tids()
40     , sleep()
41     , count() {
42 }
43 
44 ReportMop::ReportMop()
45     : mset() {
46 }
47 
48 ReportDesc::~ReportDesc() {
49   // FIXME(dvyukov): it must be leaking a lot of memory.
50 }
51 
52 #if !SANITIZER_GO
53 
54 const int kThreadBufSize = 32;
55 const char *thread_name(char *buf, Tid tid) {
56   if (tid == kMainTid)
57     return "main thread";
58   internal_snprintf(buf, kThreadBufSize, "thread T%d", tid);
59   return buf;
60 }
61 
62 static const char *ReportTypeString(ReportType typ, uptr tag) {
63   switch (typ) {
64     case ReportTypeRace:
65       return "data race";
66     case ReportTypeVptrRace:
67       return "data race on vptr (ctor/dtor vs virtual call)";
68     case ReportTypeUseAfterFree:
69       return "heap-use-after-free";
70     case ReportTypeVptrUseAfterFree:
71       return "heap-use-after-free (virtual call vs free)";
72     case ReportTypeExternalRace: {
73       const char *str = GetReportHeaderFromTag(tag);
74       return str ? str : "race on external object";
75     }
76     case ReportTypeThreadLeak:
77       return "thread leak";
78     case ReportTypeMutexDestroyLocked:
79       return "destroy of a locked mutex";
80     case ReportTypeMutexDoubleLock:
81       return "double lock of a mutex";
82     case ReportTypeMutexInvalidAccess:
83       return "use of an invalid mutex (e.g. uninitialized or destroyed)";
84     case ReportTypeMutexBadUnlock:
85       return "unlock of an unlocked mutex (or by a wrong thread)";
86     case ReportTypeMutexBadReadLock:
87       return "read lock of a write locked mutex";
88     case ReportTypeMutexBadReadUnlock:
89       return "read unlock of a write locked mutex";
90     case ReportTypeSignalUnsafe:
91       return "signal-unsafe call inside of a signal";
92     case ReportTypeErrnoInSignal:
93       return "signal handler spoils errno";
94     case ReportTypeDeadlock:
95       return "lock-order-inversion (potential deadlock)";
96     case ReportTypeMutexHeldWrongContext:
97       return "mutex held in the wrong context";
98       // No default case so compiler warns us if we miss one
99   }
100   UNREACHABLE("missing case");
101 }
102 
103 void PrintStack(const ReportStack *ent) {
104   if (ent == 0 || ent->frames == 0) {
105     Printf("    [failed to restore the stack]\n\n");
106     return;
107   }
108   SymbolizedStack *frame = ent->frames;
109   for (int i = 0; frame && frame->info.address; frame = frame->next, i++) {
110     InternalScopedString res;
111     StackTracePrinter::GetOrInit()->RenderFrame(
112         &res, common_flags()->stack_trace_format, i, frame->info.address,
113         &frame->info, common_flags()->symbolize_vs_style,
114         common_flags()->strip_path_prefix);
115     Printf("%s\n", res.data());
116   }
117   Printf("\n");
118 }
119 
120 static void PrintMutexSet(Vector<ReportMopMutex> const& mset) {
121   for (uptr i = 0; i < mset.Size(); i++) {
122     if (i == 0)
123       Printf(" (mutexes:");
124     const ReportMopMutex m = mset[i];
125     Printf(" %s M%u", m.write ? "write" : "read", m.id);
126     Printf(i == mset.Size() - 1 ? ")" : ",");
127   }
128 }
129 
130 static const char *MopDesc(bool first, bool write, bool atomic) {
131   return atomic ? (first ? (write ? "Atomic write" : "Atomic read")
132                 : (write ? "Previous atomic write" : "Previous atomic read"))
133                 : (first ? (write ? "Write" : "Read")
134                 : (write ? "Previous write" : "Previous read"));
135 }
136 
137 static const char *ExternalMopDesc(bool first, bool write) {
138   return first ? (write ? "Modifying" : "Read-only")
139                : (write ? "Previous modifying" : "Previous read-only");
140 }
141 
142 static void PrintMop(const ReportMop *mop, bool first) {
143   Decorator d;
144   char thrbuf[kThreadBufSize];
145   Printf("%s", d.Access());
146   if (mop->external_tag == kExternalTagNone) {
147     Printf("  %s of size %d at %p by %s",
148            MopDesc(first, mop->write, mop->atomic), mop->size,
149            (void *)mop->addr, thread_name(thrbuf, mop->tid));
150   } else {
151     const char *object_type = GetObjectTypeFromTag(mop->external_tag);
152     if (object_type == nullptr)
153         object_type = "external object";
154     Printf("  %s access of %s at %p by %s",
155            ExternalMopDesc(first, mop->write), object_type,
156            (void *)mop->addr, thread_name(thrbuf, mop->tid));
157   }
158   PrintMutexSet(mop->mset);
159   Printf(":\n");
160   Printf("%s", d.Default());
161   PrintStack(mop->stack);
162 }
163 
164 static void PrintLocation(const ReportLocation *loc) {
165   Decorator d;
166   char thrbuf[kThreadBufSize];
167   bool print_stack = false;
168   Printf("%s", d.Location());
169   if (loc->type == ReportLocationGlobal) {
170     const DataInfo &global = loc->global;
171     if (global.size != 0)
172       Printf("  Location is global '%s' of size %zu at %p (%s+0x%zx)\n\n",
173              global.name, global.size, reinterpret_cast<void *>(global.start),
174              StripModuleName(global.module), global.module_offset);
175     else
176       Printf("  Location is global '%s' at %p (%s+0x%zx)\n\n", global.name,
177              reinterpret_cast<void *>(global.start),
178              StripModuleName(global.module), global.module_offset);
179   } else if (loc->type == ReportLocationHeap) {
180     char thrbuf[kThreadBufSize];
181     const char *object_type = GetObjectTypeFromTag(loc->external_tag);
182     if (!object_type) {
183       Printf("  Location is heap block of size %zu at %p allocated by %s:\n",
184              loc->heap_chunk_size,
185              reinterpret_cast<void *>(loc->heap_chunk_start),
186              thread_name(thrbuf, loc->tid));
187     } else {
188       Printf("  Location is %s of size %zu at %p allocated by %s:\n",
189              object_type, loc->heap_chunk_size,
190              reinterpret_cast<void *>(loc->heap_chunk_start),
191              thread_name(thrbuf, loc->tid));
192     }
193     print_stack = true;
194   } else if (loc->type == ReportLocationStack) {
195     Printf("  Location is stack of %s.\n\n", thread_name(thrbuf, loc->tid));
196   } else if (loc->type == ReportLocationTLS) {
197     Printf("  Location is TLS of %s.\n\n", thread_name(thrbuf, loc->tid));
198   } else if (loc->type == ReportLocationFD) {
199     Printf("  Location is file descriptor %d %s by %s at:\n", loc->fd,
200            loc->fd_closed ? "destroyed" : "created",
201            thread_name(thrbuf, loc->tid));
202     print_stack = true;
203   }
204   Printf("%s", d.Default());
205   if (print_stack)
206     PrintStack(loc->stack);
207 }
208 
209 static void PrintMutexShort(const ReportMutex *rm, const char *after) {
210   Decorator d;
211   Printf("%sM%d%s%s", d.Mutex(), rm->id, d.Default(), after);
212 }
213 
214 static void PrintMutexShortWithAddress(const ReportMutex *rm,
215                                        const char *after) {
216   Decorator d;
217   Printf("%sM%d (%p)%s%s", d.Mutex(), rm->id,
218          reinterpret_cast<void *>(rm->addr), d.Default(), after);
219 }
220 
221 static void PrintMutex(const ReportMutex *rm) {
222   Decorator d;
223   Printf("%s", d.Mutex());
224   Printf("  Mutex M%u (%p) created at:\n", rm->id,
225          reinterpret_cast<void *>(rm->addr));
226   Printf("%s", d.Default());
227   PrintStack(rm->stack);
228 }
229 
230 static void PrintThread(const ReportThread *rt) {
231   Decorator d;
232   if (rt->id == kMainTid)  // Little sense in describing the main thread.
233     return;
234   Printf("%s", d.ThreadDescription());
235   Printf("  Thread T%d", rt->id);
236   if (rt->name && rt->name[0] != '\0')
237     Printf(" '%s'", rt->name);
238   char thrbuf[kThreadBufSize];
239   const char *thread_status = rt->running ? "running" : "finished";
240   if (rt->thread_type == ThreadType::Worker) {
241     Printf(" (tid=%llu, %s) is a GCD worker thread\n", rt->os_id,
242            thread_status);
243     Printf("\n");
244     Printf("%s", d.Default());
245     return;
246   }
247   Printf(" (tid=%llu, %s) created by %s", rt->os_id, thread_status,
248          thread_name(thrbuf, rt->parent_tid));
249   if (rt->stack)
250     Printf(" at:");
251   Printf("\n");
252   Printf("%s", d.Default());
253   PrintStack(rt->stack);
254 }
255 
256 static void PrintSleep(const ReportStack *s) {
257   Decorator d;
258   Printf("%s", d.Sleep());
259   Printf("  As if synchronized via sleep:\n");
260   Printf("%s", d.Default());
261   PrintStack(s);
262 }
263 
264 static ReportStack *ChooseSummaryStack(const ReportDesc *rep) {
265   if (rep->mops.Size())
266     return rep->mops[0]->stack;
267   if (rep->stacks.Size())
268     return rep->stacks[0];
269   if (rep->mutexes.Size())
270     return rep->mutexes[0]->stack;
271   if (rep->threads.Size())
272     return rep->threads[0]->stack;
273   return 0;
274 }
275 
276 static const SymbolizedStack *SkipTsanInternalFrames(SymbolizedStack *frames) {
277   if (const SymbolizedStack *f = SkipInternalFrames(frames))
278     return f;
279   return frames;  // Fallback to the top frame.
280 }
281 
282 void PrintReport(const ReportDesc *rep) {
283   Decorator d;
284   Printf("==================\n");
285   const char *rep_typ_str = ReportTypeString(rep->typ, rep->tag);
286   Printf("%s", d.Warning());
287   Printf("WARNING: ThreadSanitizer: %s (pid=%d)\n", rep_typ_str,
288          (int)internal_getpid());
289   Printf("%s", d.Default());
290 
291   if (rep->typ == ReportTypeErrnoInSignal)
292     Printf("  Signal %u handler invoked at:\n", rep->signum);
293 
294   if (rep->typ == ReportTypeDeadlock) {
295     char thrbuf[kThreadBufSize];
296     Printf("  Cycle in lock order graph: ");
297     for (uptr i = 0; i < rep->mutexes.Size(); i++)
298       PrintMutexShortWithAddress(rep->mutexes[i], " => ");
299     PrintMutexShort(rep->mutexes[0], "\n\n");
300     CHECK_GT(rep->mutexes.Size(), 0U);
301     CHECK_EQ(rep->mutexes.Size() * (flags()->second_deadlock_stack ? 2 : 1),
302              rep->stacks.Size());
303     for (uptr i = 0; i < rep->mutexes.Size(); i++) {
304       Printf("  Mutex ");
305       PrintMutexShort(rep->mutexes[(i + 1) % rep->mutexes.Size()],
306                       " acquired here while holding mutex ");
307       PrintMutexShort(rep->mutexes[i], " in ");
308       Printf("%s", d.ThreadDescription());
309       Printf("%s:\n", thread_name(thrbuf, rep->unique_tids[i]));
310       Printf("%s", d.Default());
311       if (flags()->second_deadlock_stack) {
312         PrintStack(rep->stacks[2*i]);
313         Printf("  Mutex ");
314         PrintMutexShort(rep->mutexes[i],
315                         " previously acquired by the same thread here:\n");
316         PrintStack(rep->stacks[2*i+1]);
317       } else {
318         PrintStack(rep->stacks[i]);
319         if (i == 0)
320           Printf("    Hint: use TSAN_OPTIONS=second_deadlock_stack=1 "
321                  "to get more informative warning message\n\n");
322       }
323     }
324   } else {
325     for (uptr i = 0; i < rep->stacks.Size(); i++) {
326       if (i)
327         Printf("  and:\n");
328       PrintStack(rep->stacks[i]);
329     }
330   }
331 
332   for (uptr i = 0; i < rep->mops.Size(); i++)
333     PrintMop(rep->mops[i], i == 0);
334 
335   if (rep->sleep)
336     PrintSleep(rep->sleep);
337 
338   for (uptr i = 0; i < rep->locs.Size(); i++)
339     PrintLocation(rep->locs[i]);
340 
341   if (rep->typ != ReportTypeDeadlock) {
342     for (uptr i = 0; i < rep->mutexes.Size(); i++)
343       PrintMutex(rep->mutexes[i]);
344   }
345 
346   for (uptr i = 0; i < rep->threads.Size(); i++)
347     PrintThread(rep->threads[i]);
348 
349   if (rep->typ == ReportTypeThreadLeak && rep->count > 1)
350     Printf("  And %d more similar thread leaks.\n\n", rep->count - 1);
351 
352   if (ReportStack *stack = ChooseSummaryStack(rep)) {
353     if (const SymbolizedStack *frame = SkipTsanInternalFrames(stack->frames))
354       ReportErrorSummary(rep_typ_str, frame->info);
355   }
356 
357   if (common_flags()->print_module_map == 2)
358     DumpProcessMap();
359 
360   Printf("==================\n");
361 }
362 
363 #else  // #if !SANITIZER_GO
364 
365 const Tid kMainGoroutineId = 1;
366 
367 void PrintStack(const ReportStack *ent) {
368   if (ent == 0 || ent->frames == 0) {
369     Printf("  [failed to restore the stack]\n");
370     return;
371   }
372   SymbolizedStack *frame = ent->frames;
373   for (int i = 0; frame; frame = frame->next, i++) {
374     const AddressInfo &info = frame->info;
375     Printf("  %s()\n      %s:%d +0x%zx\n", info.function,
376            StripPathPrefix(info.file, common_flags()->strip_path_prefix),
377            info.line, info.module_offset);
378   }
379 }
380 
381 static void PrintMop(const ReportMop *mop, bool first) {
382   Printf("\n");
383   Printf("%s at %p by ",
384          (first ? (mop->write ? "Write" : "Read")
385                 : (mop->write ? "Previous write" : "Previous read")),
386          reinterpret_cast<void *>(mop->addr));
387   if (mop->tid == kMainGoroutineId)
388     Printf("main goroutine:\n");
389   else
390     Printf("goroutine %d:\n", mop->tid);
391   PrintStack(mop->stack);
392 }
393 
394 static void PrintLocation(const ReportLocation *loc) {
395   switch (loc->type) {
396   case ReportLocationHeap: {
397     Printf("\n");
398     Printf("Heap block of size %zu at %p allocated by ", loc->heap_chunk_size,
399            reinterpret_cast<void *>(loc->heap_chunk_start));
400     if (loc->tid == kMainGoroutineId)
401       Printf("main goroutine:\n");
402     else
403       Printf("goroutine %d:\n", loc->tid);
404     PrintStack(loc->stack);
405     break;
406   }
407   case ReportLocationGlobal: {
408     Printf("\n");
409     Printf("Global var %s of size %zu at %p declared at %s:%zu\n",
410            loc->global.name, loc->global.size,
411            reinterpret_cast<void *>(loc->global.start), loc->global.file,
412            loc->global.line);
413     break;
414   }
415   default:
416     break;
417   }
418 }
419 
420 static void PrintThread(const ReportThread *rt) {
421   if (rt->id == kMainGoroutineId)
422     return;
423   Printf("\n");
424   Printf("Goroutine %d (%s) created at:\n",
425     rt->id, rt->running ? "running" : "finished");
426   PrintStack(rt->stack);
427 }
428 
429 void PrintReport(const ReportDesc *rep) {
430   Printf("==================\n");
431   if (rep->typ == ReportTypeRace) {
432     Printf("WARNING: DATA RACE");
433     for (uptr i = 0; i < rep->mops.Size(); i++)
434       PrintMop(rep->mops[i], i == 0);
435     for (uptr i = 0; i < rep->locs.Size(); i++)
436       PrintLocation(rep->locs[i]);
437     for (uptr i = 0; i < rep->threads.Size(); i++)
438       PrintThread(rep->threads[i]);
439   } else if (rep->typ == ReportTypeDeadlock) {
440     Printf("WARNING: DEADLOCK\n");
441     for (uptr i = 0; i < rep->mutexes.Size(); i++) {
442       Printf("Goroutine %d lock mutex %u while holding mutex %u:\n", 999,
443              rep->mutexes[i]->id,
444              rep->mutexes[(i + 1) % rep->mutexes.Size()]->id);
445       PrintStack(rep->stacks[2*i]);
446       Printf("\n");
447       Printf("Mutex %u was previously locked here:\n",
448              rep->mutexes[(i + 1) % rep->mutexes.Size()]->id);
449       PrintStack(rep->stacks[2*i + 1]);
450       Printf("\n");
451     }
452   }
453   Printf("==================\n");
454 }
455 
456 #endif
457 
458 }  // namespace __tsan
459