1 //===-- tsan_debugging.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 // TSan debugging API implementation.
12 //===----------------------------------------------------------------------===//
13 #include "tsan_interface.h"
14 #include "tsan_report.h"
15 #include "tsan_rtl.h"
16 
17 #include "sanitizer_common/sanitizer_stackdepot.h"
18 
19 using namespace __tsan;
20 
ReportTypeDescription(ReportType typ)21 static const char *ReportTypeDescription(ReportType typ) {
22   switch (typ) {
23     case ReportTypeRace: return "data-race";
24     case ReportTypeVptrRace: return "data-race-vptr";
25     case ReportTypeUseAfterFree: return "heap-use-after-free";
26     case ReportTypeVptrUseAfterFree: return "heap-use-after-free-vptr";
27     case ReportTypeExternalRace: return "external-race";
28     case ReportTypeThreadLeak: return "thread-leak";
29     case ReportTypeMutexDestroyLocked: return "locked-mutex-destroy";
30     case ReportTypeMutexDoubleLock: return "mutex-double-lock";
31     case ReportTypeMutexInvalidAccess: return "mutex-invalid-access";
32     case ReportTypeMutexBadUnlock: return "mutex-bad-unlock";
33     case ReportTypeMutexBadReadLock: return "mutex-bad-read-lock";
34     case ReportTypeMutexBadReadUnlock: return "mutex-bad-read-unlock";
35     case ReportTypeSignalUnsafe: return "signal-unsafe-call";
36     case ReportTypeErrnoInSignal: return "errno-in-signal-handler";
37     case ReportTypeDeadlock: return "lock-order-inversion";
38     case ReportTypeMutexHeldWrongContext:
39       return "mutex-held-in-wrong-context";
40       // No default case so compiler warns us if we miss one
41   }
42   UNREACHABLE("missing case");
43 }
44 
ReportLocationTypeDescription(ReportLocationType typ)45 static const char *ReportLocationTypeDescription(ReportLocationType typ) {
46   switch (typ) {
47     case ReportLocationGlobal: return "global";
48     case ReportLocationHeap: return "heap";
49     case ReportLocationStack: return "stack";
50     case ReportLocationTLS: return "tls";
51     case ReportLocationFD: return "fd";
52     // No default case so compiler warns us if we miss one
53   }
54   UNREACHABLE("missing case");
55 }
56 
CopyTrace(SymbolizedStack * first_frame,void ** trace,uptr trace_size)57 static void CopyTrace(SymbolizedStack *first_frame, void **trace,
58                       uptr trace_size) {
59   uptr i = 0;
60   for (SymbolizedStack *frame = first_frame; frame != nullptr;
61        frame = frame->next) {
62     trace[i++] = (void *)frame->info.address;
63     if (i >= trace_size) break;
64   }
65 }
66 
67 // Meant to be called by the debugger.
68 SANITIZER_INTERFACE_ATTRIBUTE
__tsan_get_current_report()69 void *__tsan_get_current_report() {
70   return const_cast<ReportDesc*>(cur_thread()->current_report);
71 }
72 
73 SANITIZER_INTERFACE_ATTRIBUTE
__tsan_get_report_data(void * report,const char ** description,int * count,int * stack_count,int * mop_count,int * loc_count,int * mutex_count,int * thread_count,int * unique_tid_count,void ** sleep_trace,uptr trace_size)74 int __tsan_get_report_data(void *report, const char **description, int *count,
75                            int *stack_count, int *mop_count, int *loc_count,
76                            int *mutex_count, int *thread_count,
77                            int *unique_tid_count, void **sleep_trace,
78                            uptr trace_size) {
79   const ReportDesc *rep = (ReportDesc *)report;
80   *description = ReportTypeDescription(rep->typ);
81   *count = rep->count;
82   *stack_count = rep->stacks.Size();
83   *mop_count = rep->mops.Size();
84   *loc_count = rep->locs.Size();
85   *mutex_count = rep->mutexes.Size();
86   *thread_count = rep->threads.Size();
87   *unique_tid_count = rep->unique_tids.Size();
88   if (rep->sleep) CopyTrace(rep->sleep->frames, sleep_trace, trace_size);
89   return 1;
90 }
91 
92 SANITIZER_INTERFACE_ATTRIBUTE
__tsan_get_report_tag(void * report,uptr * tag)93 int __tsan_get_report_tag(void *report, uptr *tag) {
94   const ReportDesc *rep = (ReportDesc *)report;
95   *tag = rep->tag;
96   return 1;
97 }
98 
99 SANITIZER_INTERFACE_ATTRIBUTE
__tsan_get_report_stack(void * report,uptr idx,void ** trace,uptr trace_size)100 int __tsan_get_report_stack(void *report, uptr idx, void **trace,
101                             uptr trace_size) {
102   const ReportDesc *rep = (ReportDesc *)report;
103   CHECK_LT(idx, rep->stacks.Size());
104   ReportStack *stack = rep->stacks[idx];
105   if (stack) CopyTrace(stack->frames, trace, trace_size);
106   return stack ? 1 : 0;
107 }
108 
109 SANITIZER_INTERFACE_ATTRIBUTE
__tsan_get_report_mop(void * report,uptr idx,int * tid,void ** addr,int * size,int * write,int * atomic,void ** trace,uptr trace_size)110 int __tsan_get_report_mop(void *report, uptr idx, int *tid, void **addr,
111                           int *size, int *write, int *atomic, void **trace,
112                           uptr trace_size) {
113   const ReportDesc *rep = (ReportDesc *)report;
114   CHECK_LT(idx, rep->mops.Size());
115   ReportMop *mop = rep->mops[idx];
116   *tid = mop->tid;
117   *addr = (void *)mop->addr;
118   *size = mop->size;
119   *write = mop->write ? 1 : 0;
120   *atomic = mop->atomic ? 1 : 0;
121   if (mop->stack) CopyTrace(mop->stack->frames, trace, trace_size);
122   return 1;
123 }
124 
125 SANITIZER_INTERFACE_ATTRIBUTE
__tsan_get_report_loc(void * report,uptr idx,const char ** type,void ** addr,uptr * start,uptr * size,int * tid,int * fd,int * suppressable,void ** trace,uptr trace_size)126 int __tsan_get_report_loc(void *report, uptr idx, const char **type,
127                           void **addr, uptr *start, uptr *size, int *tid,
128                           int *fd, int *suppressable, void **trace,
129                           uptr trace_size) {
130   const ReportDesc *rep = (ReportDesc *)report;
131   CHECK_LT(idx, rep->locs.Size());
132   ReportLocation *loc = rep->locs[idx];
133   *type = ReportLocationTypeDescription(loc->type);
134   *addr = (void *)loc->global.start;
135   *start = loc->heap_chunk_start;
136   *size = loc->heap_chunk_size;
137   *tid = loc->tid;
138   *fd = loc->fd;
139   *suppressable = loc->suppressable;
140   if (loc->stack) CopyTrace(loc->stack->frames, trace, trace_size);
141   return 1;
142 }
143 
144 SANITIZER_INTERFACE_ATTRIBUTE
__tsan_get_report_loc_object_type(void * report,uptr idx,const char ** object_type)145 int __tsan_get_report_loc_object_type(void *report, uptr idx,
146                                       const char **object_type) {
147   const ReportDesc *rep = (ReportDesc *)report;
148   CHECK_LT(idx, rep->locs.Size());
149   ReportLocation *loc = rep->locs[idx];
150   *object_type = GetObjectTypeFromTag(loc->external_tag);
151   return 1;
152 }
153 
154 SANITIZER_INTERFACE_ATTRIBUTE
__tsan_get_report_mutex(void * report,uptr idx,uptr * mutex_id,void ** addr,int * destroyed,void ** trace,uptr trace_size)155 int __tsan_get_report_mutex(void *report, uptr idx, uptr *mutex_id, void **addr,
156                             int *destroyed, void **trace, uptr trace_size) {
157   const ReportDesc *rep = (ReportDesc *)report;
158   CHECK_LT(idx, rep->mutexes.Size());
159   ReportMutex *mutex = rep->mutexes[idx];
160   *mutex_id = mutex->id;
161   *addr = (void *)mutex->addr;
162   *destroyed = false;
163   if (mutex->stack) CopyTrace(mutex->stack->frames, trace, trace_size);
164   return 1;
165 }
166 
167 SANITIZER_INTERFACE_ATTRIBUTE
__tsan_get_report_thread(void * report,uptr idx,int * tid,tid_t * os_id,int * running,const char ** name,int * parent_tid,void ** trace,uptr trace_size)168 int __tsan_get_report_thread(void *report, uptr idx, int *tid, tid_t *os_id,
169                              int *running, const char **name, int *parent_tid,
170                              void **trace, uptr trace_size) {
171   const ReportDesc *rep = (ReportDesc *)report;
172   CHECK_LT(idx, rep->threads.Size());
173   ReportThread *thread = rep->threads[idx];
174   *tid = thread->id;
175   *os_id = thread->os_id;
176   *running = thread->running;
177   *name = thread->name;
178   *parent_tid = thread->parent_tid;
179   if (thread->stack) CopyTrace(thread->stack->frames, trace, trace_size);
180   return 1;
181 }
182 
183 SANITIZER_INTERFACE_ATTRIBUTE
__tsan_get_report_unique_tid(void * report,uptr idx,int * tid)184 int __tsan_get_report_unique_tid(void *report, uptr idx, int *tid) {
185   const ReportDesc *rep = (ReportDesc *)report;
186   CHECK_LT(idx, rep->unique_tids.Size());
187   *tid = rep->unique_tids[idx];
188   return 1;
189 }
190 
191 SANITIZER_INTERFACE_ATTRIBUTE
__tsan_locate_address(uptr addr,char * name,uptr name_size,uptr * region_address_ptr,uptr * region_size_ptr)192 const char *__tsan_locate_address(uptr addr, char *name, uptr name_size,
193                                   uptr *region_address_ptr,
194                                   uptr *region_size_ptr) {
195   uptr region_address = 0;
196   uptr region_size = 0;
197   const char *region_kind = nullptr;
198   if (name && name_size > 0) name[0] = 0;
199 
200   if (IsMetaMem(reinterpret_cast<u32 *>(addr))) {
201     region_kind = "meta shadow";
202   } else if (IsShadowMem(reinterpret_cast<RawShadow *>(addr))) {
203     region_kind = "shadow";
204   } else {
205     bool is_stack = false;
206     MBlock *b = 0;
207     Allocator *a = allocator();
208     if (a->PointerIsMine((void *)addr)) {
209       void *block_begin = a->GetBlockBegin((void *)addr);
210       if (block_begin) b = ctx->metamap.GetBlock((uptr)block_begin);
211     }
212 
213     if (b != 0) {
214       region_address = (uptr)allocator()->GetBlockBegin((void *)addr);
215       region_size = b->siz;
216       region_kind = "heap";
217     } else {
218       // TODO(kuba.brecka): We should not lock. This is supposed to be called
219       // from within the debugger when other threads are stopped.
220       ctx->thread_registry.Lock();
221       ThreadContext *tctx = IsThreadStackOrTls(addr, &is_stack);
222       ctx->thread_registry.Unlock();
223       if (tctx) {
224         region_kind = is_stack ? "stack" : "tls";
225       } else {
226         region_kind = "global";
227         DataInfo info;
228         if (Symbolizer::GetOrInit()->SymbolizeData(addr, &info)) {
229           internal_strncpy(name, info.name, name_size);
230           region_address = info.start;
231           region_size = info.size;
232         }
233       }
234     }
235   }
236 
237   CHECK(region_kind);
238   if (region_address_ptr) *region_address_ptr = region_address;
239   if (region_size_ptr) *region_size_ptr = region_size;
240   return region_kind;
241 }
242 
243 SANITIZER_INTERFACE_ATTRIBUTE
__tsan_get_alloc_stack(uptr addr,uptr * trace,uptr size,int * thread_id,tid_t * os_id)244 int __tsan_get_alloc_stack(uptr addr, uptr *trace, uptr size, int *thread_id,
245                            tid_t *os_id) {
246   MBlock *b = 0;
247   Allocator *a = allocator();
248   if (a->PointerIsMine((void *)addr)) {
249     void *block_begin = a->GetBlockBegin((void *)addr);
250     if (block_begin) b = ctx->metamap.GetBlock((uptr)block_begin);
251   }
252   if (b == 0) return 0;
253 
254   *thread_id = b->tid;
255   // No locking.  This is supposed to be called from within the debugger when
256   // other threads are stopped.
257   ThreadContextBase *tctx = ctx->thread_registry.GetThreadLocked(b->tid);
258   *os_id = tctx->os_id;
259 
260   StackTrace stack = StackDepotGet(b->stk);
261   size = Min(size, (uptr)stack.size);
262   for (uptr i = 0; i < size; i++) trace[i] = stack.trace[stack.size - i - 1];
263   return size;
264 }
265