backtrace_test.cpp revision 837eff22c86bcdddd50c68315ef17792a0d1949a
1/* 2 * Copyright (C) 2013 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17#define _GNU_SOURCE 1 18#include <dirent.h> 19#include <dlfcn.h> 20#include <errno.h> 21#include <fcntl.h> 22#include <inttypes.h> 23#include <pthread.h> 24#include <signal.h> 25#include <stdint.h> 26#include <stdio.h> 27#include <stdlib.h> 28#include <string.h> 29#include <sys/ptrace.h> 30#include <sys/stat.h> 31#include <sys/types.h> 32#include <sys/wait.h> 33#include <time.h> 34#include <unistd.h> 35 36#include <algorithm> 37#include <list> 38#include <memory> 39#include <string> 40#include <vector> 41 42#include <backtrace/Backtrace.h> 43#include <backtrace/BacktraceMap.h> 44 45#include <base/stringprintf.h> 46#include <cutils/atomic.h> 47#include <cutils/threads.h> 48 49#include <gtest/gtest.h> 50 51// For the THREAD_SIGNAL definition. 52#include "BacktraceCurrent.h" 53#include "thread_utils.h" 54 55// Number of microseconds per milliseconds. 56#define US_PER_MSEC 1000 57 58// Number of nanoseconds in a second. 59#define NS_PER_SEC 1000000000ULL 60 61// Number of simultaneous dumping operations to perform. 62#define NUM_THREADS 40 63 64// Number of simultaneous threads running in our forked process. 65#define NUM_PTRACE_THREADS 5 66 67struct thread_t { 68 pid_t tid; 69 int32_t state; 70 pthread_t threadId; 71 void* data; 72}; 73 74struct dump_thread_t { 75 thread_t thread; 76 Backtrace* backtrace; 77 int32_t* now; 78 int32_t done; 79}; 80 81extern "C" { 82// Prototypes for functions in the test library. 83int test_level_one(int, int, int, int, void (*)(void*), void*); 84 85int test_recursive_call(int, void (*)(void*), void*); 86} 87 88uint64_t NanoTime() { 89 struct timespec t = { 0, 0 }; 90 clock_gettime(CLOCK_MONOTONIC, &t); 91 return static_cast<uint64_t>(t.tv_sec * NS_PER_SEC + t.tv_nsec); 92} 93 94std::string DumpFrames(Backtrace* backtrace) { 95 if (backtrace->NumFrames() == 0) { 96 return " No frames to dump.\n"; 97 } 98 99 std::string frame; 100 for (size_t i = 0; i < backtrace->NumFrames(); i++) { 101 frame += " " + backtrace->FormatFrameData(i) + '\n'; 102 } 103 return frame; 104} 105 106void WaitForStop(pid_t pid) { 107 uint64_t start = NanoTime(); 108 109 siginfo_t si; 110 while (ptrace(PTRACE_GETSIGINFO, pid, 0, &si) < 0 && (errno == EINTR || errno == ESRCH)) { 111 if ((NanoTime() - start) > NS_PER_SEC) { 112 printf("The process did not get to a stopping point in 1 second.\n"); 113 break; 114 } 115 usleep(US_PER_MSEC); 116 } 117} 118 119bool ReadyLevelBacktrace(Backtrace* backtrace) { 120 // See if test_level_four is in the backtrace. 121 bool found = false; 122 for (Backtrace::const_iterator it = backtrace->begin(); it != backtrace->end(); ++it) { 123 if (it->func_name == "test_level_four") { 124 found = true; 125 break; 126 } 127 } 128 129 return found; 130} 131 132void VerifyLevelDump(Backtrace* backtrace) { 133 ASSERT_GT(backtrace->NumFrames(), static_cast<size_t>(0)) 134 << DumpFrames(backtrace); 135 ASSERT_LT(backtrace->NumFrames(), static_cast<size_t>(MAX_BACKTRACE_FRAMES)) 136 << DumpFrames(backtrace); 137 138 // Look through the frames starting at the highest to find the 139 // frame we want. 140 size_t frame_num = 0; 141 for (size_t i = backtrace->NumFrames()-1; i > 2; i--) { 142 if (backtrace->GetFrame(i)->func_name == "test_level_one") { 143 frame_num = i; 144 break; 145 } 146 } 147 ASSERT_LT(static_cast<size_t>(0), frame_num) << DumpFrames(backtrace); 148 ASSERT_LE(static_cast<size_t>(3), frame_num) << DumpFrames(backtrace); 149 150 ASSERT_EQ(backtrace->GetFrame(frame_num)->func_name, "test_level_one") 151 << DumpFrames(backtrace); 152 ASSERT_EQ(backtrace->GetFrame(frame_num-1)->func_name, "test_level_two") 153 << DumpFrames(backtrace); 154 ASSERT_EQ(backtrace->GetFrame(frame_num-2)->func_name, "test_level_three") 155 << DumpFrames(backtrace); 156 ASSERT_EQ(backtrace->GetFrame(frame_num-3)->func_name, "test_level_four") 157 << DumpFrames(backtrace); 158} 159 160void VerifyLevelBacktrace(void*) { 161 std::unique_ptr<Backtrace> backtrace( 162 Backtrace::Create(BACKTRACE_CURRENT_PROCESS, BACKTRACE_CURRENT_THREAD)); 163 ASSERT_TRUE(backtrace.get() != nullptr); 164 ASSERT_TRUE(backtrace->Unwind(0)); 165 166 VerifyLevelDump(backtrace.get()); 167} 168 169bool ReadyMaxBacktrace(Backtrace* backtrace) { 170 return (backtrace->NumFrames() == MAX_BACKTRACE_FRAMES); 171} 172 173void VerifyMaxDump(Backtrace* backtrace) { 174 ASSERT_EQ(backtrace->NumFrames(), static_cast<size_t>(MAX_BACKTRACE_FRAMES)) 175 << DumpFrames(backtrace); 176 // Verify that the last frame is our recursive call. 177 ASSERT_EQ(backtrace->GetFrame(MAX_BACKTRACE_FRAMES-1)->func_name, "test_recursive_call") 178 << DumpFrames(backtrace); 179} 180 181void VerifyMaxBacktrace(void*) { 182 std::unique_ptr<Backtrace> backtrace( 183 Backtrace::Create(BACKTRACE_CURRENT_PROCESS, BACKTRACE_CURRENT_THREAD)); 184 ASSERT_TRUE(backtrace.get() != nullptr); 185 ASSERT_TRUE(backtrace->Unwind(0)); 186 187 VerifyMaxDump(backtrace.get()); 188} 189 190void ThreadSetState(void* data) { 191 thread_t* thread = reinterpret_cast<thread_t*>(data); 192 android_atomic_acquire_store(1, &thread->state); 193 volatile int i = 0; 194 while (thread->state) { 195 i++; 196 } 197} 198 199void VerifyThreadTest(pid_t tid, void (*VerifyFunc)(Backtrace*)) { 200 std::unique_ptr<Backtrace> backtrace(Backtrace::Create(getpid(), tid)); 201 ASSERT_TRUE(backtrace.get() != nullptr); 202 ASSERT_TRUE(backtrace->Unwind(0)); 203 204 VerifyFunc(backtrace.get()); 205} 206 207bool WaitForNonZero(int32_t* value, uint64_t seconds) { 208 uint64_t start = NanoTime(); 209 do { 210 if (android_atomic_acquire_load(value)) { 211 return true; 212 } 213 } while ((NanoTime() - start) < seconds * NS_PER_SEC); 214 return false; 215} 216 217TEST(libbacktrace, local_no_unwind_frames) { 218 // Verify that a local unwind does not include any frames within 219 // libunwind or libbacktrace. 220 std::unique_ptr<Backtrace> backtrace(Backtrace::Create(getpid(), getpid())); 221 ASSERT_TRUE(backtrace.get() != nullptr); 222 ASSERT_TRUE(backtrace->Unwind(0)); 223 224 ASSERT_TRUE(backtrace->NumFrames() != 0); 225 for (const auto& frame : *backtrace ) { 226 if (BacktraceMap::IsValid(frame.map)) { 227 const std::string name = basename(frame.map.name.c_str()); 228 ASSERT_TRUE(name != "libunwind.so" && name != "libbacktrace.so") 229 << DumpFrames(backtrace.get()); 230 } 231 break; 232 } 233} 234 235TEST(libbacktrace, local_trace) { 236 ASSERT_NE(test_level_one(1, 2, 3, 4, VerifyLevelBacktrace, nullptr), 0); 237} 238 239void VerifyIgnoreFrames( 240 Backtrace* bt_all, Backtrace* bt_ign1, 241 Backtrace* bt_ign2, const char* cur_proc) { 242 EXPECT_EQ(bt_all->NumFrames(), bt_ign1->NumFrames() + 1) 243 << "All backtrace:\n" << DumpFrames(bt_all) << "Ignore 1 backtrace:\n" << DumpFrames(bt_ign1); 244 EXPECT_EQ(bt_all->NumFrames(), bt_ign2->NumFrames() + 2) 245 << "All backtrace:\n" << DumpFrames(bt_all) << "Ignore 2 backtrace:\n" << DumpFrames(bt_ign2); 246 247 // Check all of the frames are the same > the current frame. 248 bool check = (cur_proc == nullptr); 249 for (size_t i = 0; i < bt_ign2->NumFrames(); i++) { 250 if (check) { 251 EXPECT_EQ(bt_ign2->GetFrame(i)->pc, bt_ign1->GetFrame(i+1)->pc); 252 EXPECT_EQ(bt_ign2->GetFrame(i)->sp, bt_ign1->GetFrame(i+1)->sp); 253 EXPECT_EQ(bt_ign2->GetFrame(i)->stack_size, bt_ign1->GetFrame(i+1)->stack_size); 254 255 EXPECT_EQ(bt_ign2->GetFrame(i)->pc, bt_all->GetFrame(i+2)->pc); 256 EXPECT_EQ(bt_ign2->GetFrame(i)->sp, bt_all->GetFrame(i+2)->sp); 257 EXPECT_EQ(bt_ign2->GetFrame(i)->stack_size, bt_all->GetFrame(i+2)->stack_size); 258 } 259 if (!check && bt_ign2->GetFrame(i)->func_name == cur_proc) { 260 check = true; 261 } 262 } 263} 264 265void VerifyLevelIgnoreFrames(void*) { 266 std::unique_ptr<Backtrace> all( 267 Backtrace::Create(BACKTRACE_CURRENT_PROCESS, BACKTRACE_CURRENT_THREAD)); 268 ASSERT_TRUE(all.get() != nullptr); 269 ASSERT_TRUE(all->Unwind(0)); 270 271 std::unique_ptr<Backtrace> ign1( 272 Backtrace::Create(BACKTRACE_CURRENT_PROCESS, BACKTRACE_CURRENT_THREAD)); 273 ASSERT_TRUE(ign1.get() != nullptr); 274 ASSERT_TRUE(ign1->Unwind(1)); 275 276 std::unique_ptr<Backtrace> ign2( 277 Backtrace::Create(BACKTRACE_CURRENT_PROCESS, BACKTRACE_CURRENT_THREAD)); 278 ASSERT_TRUE(ign2.get() != nullptr); 279 ASSERT_TRUE(ign2->Unwind(2)); 280 281 VerifyIgnoreFrames(all.get(), ign1.get(), ign2.get(), "VerifyLevelIgnoreFrames"); 282} 283 284TEST(libbacktrace, local_trace_ignore_frames) { 285 ASSERT_NE(test_level_one(1, 2, 3, 4, VerifyLevelIgnoreFrames, nullptr), 0); 286} 287 288TEST(libbacktrace, local_max_trace) { 289 ASSERT_NE(test_recursive_call(MAX_BACKTRACE_FRAMES+10, VerifyMaxBacktrace, nullptr), 0); 290} 291 292void VerifyProcTest(pid_t pid, pid_t tid, bool share_map, 293 bool (*ReadyFunc)(Backtrace*), 294 void (*VerifyFunc)(Backtrace*)) { 295 pid_t ptrace_tid; 296 if (tid < 0) { 297 ptrace_tid = pid; 298 } else { 299 ptrace_tid = tid; 300 } 301 uint64_t start = NanoTime(); 302 bool verified = false; 303 std::string last_dump; 304 do { 305 usleep(US_PER_MSEC); 306 if (ptrace(PTRACE_ATTACH, ptrace_tid, 0, 0) == 0) { 307 // Wait for the process to get to a stopping point. 308 WaitForStop(ptrace_tid); 309 310 std::unique_ptr<BacktraceMap> map; 311 if (share_map) { 312 map.reset(BacktraceMap::Create(pid)); 313 } 314 std::unique_ptr<Backtrace> backtrace(Backtrace::Create(pid, tid, map.get())); 315 ASSERT_TRUE(backtrace.get() != nullptr); 316 ASSERT_TRUE(backtrace->Unwind(0)); 317 if (ReadyFunc(backtrace.get())) { 318 VerifyFunc(backtrace.get()); 319 verified = true; 320 } else { 321 last_dump = DumpFrames(backtrace.get()); 322 } 323 324 ASSERT_TRUE(ptrace(PTRACE_DETACH, ptrace_tid, 0, 0) == 0); 325 } 326 // If 5 seconds have passed, then we are done. 327 } while (!verified && (NanoTime() - start) <= 5 * NS_PER_SEC); 328 ASSERT_TRUE(verified) << "Last backtrace:\n" << last_dump; 329} 330 331TEST(libbacktrace, ptrace_trace) { 332 pid_t pid; 333 if ((pid = fork()) == 0) { 334 ASSERT_NE(test_level_one(1, 2, 3, 4, nullptr, nullptr), 0); 335 _exit(1); 336 } 337 VerifyProcTest(pid, BACKTRACE_CURRENT_THREAD, false, ReadyLevelBacktrace, VerifyLevelDump); 338 339 kill(pid, SIGKILL); 340 int status; 341 ASSERT_EQ(waitpid(pid, &status, 0), pid); 342} 343 344TEST(libbacktrace, ptrace_trace_shared_map) { 345 pid_t pid; 346 if ((pid = fork()) == 0) { 347 ASSERT_NE(test_level_one(1, 2, 3, 4, nullptr, nullptr), 0); 348 _exit(1); 349 } 350 351 VerifyProcTest(pid, BACKTRACE_CURRENT_THREAD, true, ReadyLevelBacktrace, VerifyLevelDump); 352 353 kill(pid, SIGKILL); 354 int status; 355 ASSERT_EQ(waitpid(pid, &status, 0), pid); 356} 357 358TEST(libbacktrace, ptrace_max_trace) { 359 pid_t pid; 360 if ((pid = fork()) == 0) { 361 ASSERT_NE(test_recursive_call(MAX_BACKTRACE_FRAMES+10, nullptr, nullptr), 0); 362 _exit(1); 363 } 364 VerifyProcTest(pid, BACKTRACE_CURRENT_THREAD, false, ReadyMaxBacktrace, VerifyMaxDump); 365 366 kill(pid, SIGKILL); 367 int status; 368 ASSERT_EQ(waitpid(pid, &status, 0), pid); 369} 370 371void VerifyProcessIgnoreFrames(Backtrace* bt_all) { 372 std::unique_ptr<Backtrace> ign1(Backtrace::Create(bt_all->Pid(), BACKTRACE_CURRENT_THREAD)); 373 ASSERT_TRUE(ign1.get() != nullptr); 374 ASSERT_TRUE(ign1->Unwind(1)); 375 376 std::unique_ptr<Backtrace> ign2(Backtrace::Create(bt_all->Pid(), BACKTRACE_CURRENT_THREAD)); 377 ASSERT_TRUE(ign2.get() != nullptr); 378 ASSERT_TRUE(ign2->Unwind(2)); 379 380 VerifyIgnoreFrames(bt_all, ign1.get(), ign2.get(), nullptr); 381} 382 383TEST(libbacktrace, ptrace_ignore_frames) { 384 pid_t pid; 385 if ((pid = fork()) == 0) { 386 ASSERT_NE(test_level_one(1, 2, 3, 4, nullptr, nullptr), 0); 387 _exit(1); 388 } 389 VerifyProcTest(pid, BACKTRACE_CURRENT_THREAD, false, ReadyLevelBacktrace, VerifyProcessIgnoreFrames); 390 391 kill(pid, SIGKILL); 392 int status; 393 ASSERT_EQ(waitpid(pid, &status, 0), pid); 394} 395 396// Create a process with multiple threads and dump all of the threads. 397void* PtraceThreadLevelRun(void*) { 398 EXPECT_NE(test_level_one(1, 2, 3, 4, nullptr, nullptr), 0); 399 return nullptr; 400} 401 402void GetThreads(pid_t pid, std::vector<pid_t>* threads) { 403 // Get the list of tasks. 404 char task_path[128]; 405 snprintf(task_path, sizeof(task_path), "/proc/%d/task", pid); 406 407 DIR* tasks_dir = opendir(task_path); 408 ASSERT_TRUE(tasks_dir != nullptr); 409 struct dirent* entry; 410 while ((entry = readdir(tasks_dir)) != nullptr) { 411 char* end; 412 pid_t tid = strtoul(entry->d_name, &end, 10); 413 if (*end == '\0') { 414 threads->push_back(tid); 415 } 416 } 417 closedir(tasks_dir); 418} 419 420TEST(libbacktrace, ptrace_threads) { 421 pid_t pid; 422 if ((pid = fork()) == 0) { 423 for (size_t i = 0; i < NUM_PTRACE_THREADS; i++) { 424 pthread_attr_t attr; 425 pthread_attr_init(&attr); 426 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 427 428 pthread_t thread; 429 ASSERT_TRUE(pthread_create(&thread, &attr, PtraceThreadLevelRun, nullptr) == 0); 430 } 431 ASSERT_NE(test_level_one(1, 2, 3, 4, nullptr, nullptr), 0); 432 _exit(1); 433 } 434 435 // Check to see that all of the threads are running before unwinding. 436 std::vector<pid_t> threads; 437 uint64_t start = NanoTime(); 438 do { 439 usleep(US_PER_MSEC); 440 threads.clear(); 441 GetThreads(pid, &threads); 442 } while ((threads.size() != NUM_PTRACE_THREADS + 1) && 443 ((NanoTime() - start) <= 5 * NS_PER_SEC)); 444 ASSERT_EQ(threads.size(), static_cast<size_t>(NUM_PTRACE_THREADS + 1)); 445 446 ASSERT_TRUE(ptrace(PTRACE_ATTACH, pid, 0, 0) == 0); 447 WaitForStop(pid); 448 for (std::vector<int>::const_iterator it = threads.begin(); it != threads.end(); ++it) { 449 // Skip the current forked process, we only care about the threads. 450 if (pid == *it) { 451 continue; 452 } 453 VerifyProcTest(pid, *it, false, ReadyLevelBacktrace, VerifyLevelDump); 454 } 455 ASSERT_TRUE(ptrace(PTRACE_DETACH, pid, 0, 0) == 0); 456 457 kill(pid, SIGKILL); 458 int status; 459 ASSERT_EQ(waitpid(pid, &status, 0), pid); 460} 461 462void VerifyLevelThread(void*) { 463 std::unique_ptr<Backtrace> backtrace(Backtrace::Create(getpid(), gettid())); 464 ASSERT_TRUE(backtrace.get() != nullptr); 465 ASSERT_TRUE(backtrace->Unwind(0)); 466 467 VerifyLevelDump(backtrace.get()); 468} 469 470TEST(libbacktrace, thread_current_level) { 471 ASSERT_NE(test_level_one(1, 2, 3, 4, VerifyLevelThread, nullptr), 0); 472} 473 474void VerifyMaxThread(void*) { 475 std::unique_ptr<Backtrace> backtrace(Backtrace::Create(getpid(), gettid())); 476 ASSERT_TRUE(backtrace.get() != nullptr); 477 ASSERT_TRUE(backtrace->Unwind(0)); 478 479 VerifyMaxDump(backtrace.get()); 480} 481 482TEST(libbacktrace, thread_current_max) { 483 ASSERT_NE(test_recursive_call(MAX_BACKTRACE_FRAMES+10, VerifyMaxThread, nullptr), 0); 484} 485 486void* ThreadLevelRun(void* data) { 487 thread_t* thread = reinterpret_cast<thread_t*>(data); 488 489 thread->tid = gettid(); 490 EXPECT_NE(test_level_one(1, 2, 3, 4, ThreadSetState, data), 0); 491 return nullptr; 492} 493 494TEST(libbacktrace, thread_level_trace) { 495 pthread_attr_t attr; 496 pthread_attr_init(&attr); 497 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 498 499 thread_t thread_data = { 0, 0, 0, nullptr }; 500 pthread_t thread; 501 ASSERT_TRUE(pthread_create(&thread, &attr, ThreadLevelRun, &thread_data) == 0); 502 503 // Wait up to 2 seconds for the tid to be set. 504 ASSERT_TRUE(WaitForNonZero(&thread_data.state, 2)); 505 506 // Make sure that the thread signal used is not visible when compiled for 507 // the target. 508#if !defined(__GLIBC__) 509 ASSERT_LT(THREAD_SIGNAL, SIGRTMIN); 510#endif 511 512 // Save the current signal action and make sure it is restored afterwards. 513 struct sigaction cur_action; 514 ASSERT_TRUE(sigaction(THREAD_SIGNAL, nullptr, &cur_action) == 0); 515 516 std::unique_ptr<Backtrace> backtrace(Backtrace::Create(getpid(), thread_data.tid)); 517 ASSERT_TRUE(backtrace.get() != nullptr); 518 ASSERT_TRUE(backtrace->Unwind(0)); 519 520 VerifyLevelDump(backtrace.get()); 521 522 // Tell the thread to exit its infinite loop. 523 android_atomic_acquire_store(0, &thread_data.state); 524 525 // Verify that the old action was restored. 526 struct sigaction new_action; 527 ASSERT_TRUE(sigaction(THREAD_SIGNAL, nullptr, &new_action) == 0); 528 EXPECT_EQ(cur_action.sa_sigaction, new_action.sa_sigaction); 529 // The SA_RESTORER flag gets set behind our back, so a direct comparison 530 // doesn't work unless we mask the value off. Mips doesn't have this 531 // flag, so skip this on that platform. 532#if defined(SA_RESTORER) 533 cur_action.sa_flags &= ~SA_RESTORER; 534 new_action.sa_flags &= ~SA_RESTORER; 535#elif defined(__GLIBC__) 536 // Our host compiler doesn't appear to define this flag for some reason. 537 cur_action.sa_flags &= ~0x04000000; 538 new_action.sa_flags &= ~0x04000000; 539#endif 540 EXPECT_EQ(cur_action.sa_flags, new_action.sa_flags); 541} 542 543TEST(libbacktrace, thread_ignore_frames) { 544 pthread_attr_t attr; 545 pthread_attr_init(&attr); 546 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 547 548 thread_t thread_data = { 0, 0, 0, nullptr }; 549 pthread_t thread; 550 ASSERT_TRUE(pthread_create(&thread, &attr, ThreadLevelRun, &thread_data) == 0); 551 552 // Wait up to 2 seconds for the tid to be set. 553 ASSERT_TRUE(WaitForNonZero(&thread_data.state, 2)); 554 555 std::unique_ptr<Backtrace> all(Backtrace::Create(getpid(), thread_data.tid)); 556 ASSERT_TRUE(all.get() != nullptr); 557 ASSERT_TRUE(all->Unwind(0)); 558 559 std::unique_ptr<Backtrace> ign1(Backtrace::Create(getpid(), thread_data.tid)); 560 ASSERT_TRUE(ign1.get() != nullptr); 561 ASSERT_TRUE(ign1->Unwind(1)); 562 563 std::unique_ptr<Backtrace> ign2(Backtrace::Create(getpid(), thread_data.tid)); 564 ASSERT_TRUE(ign2.get() != nullptr); 565 ASSERT_TRUE(ign2->Unwind(2)); 566 567 VerifyIgnoreFrames(all.get(), ign1.get(), ign2.get(), nullptr); 568 569 // Tell the thread to exit its infinite loop. 570 android_atomic_acquire_store(0, &thread_data.state); 571} 572 573void* ThreadMaxRun(void* data) { 574 thread_t* thread = reinterpret_cast<thread_t*>(data); 575 576 thread->tid = gettid(); 577 EXPECT_NE(test_recursive_call(MAX_BACKTRACE_FRAMES+10, ThreadSetState, data), 0); 578 return nullptr; 579} 580 581TEST(libbacktrace, thread_max_trace) { 582 pthread_attr_t attr; 583 pthread_attr_init(&attr); 584 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 585 586 thread_t thread_data = { 0, 0, 0, nullptr }; 587 pthread_t thread; 588 ASSERT_TRUE(pthread_create(&thread, &attr, ThreadMaxRun, &thread_data) == 0); 589 590 // Wait for the tid to be set. 591 ASSERT_TRUE(WaitForNonZero(&thread_data.state, 2)); 592 593 std::unique_ptr<Backtrace> backtrace(Backtrace::Create(getpid(), thread_data.tid)); 594 ASSERT_TRUE(backtrace.get() != nullptr); 595 ASSERT_TRUE(backtrace->Unwind(0)); 596 597 VerifyMaxDump(backtrace.get()); 598 599 // Tell the thread to exit its infinite loop. 600 android_atomic_acquire_store(0, &thread_data.state); 601} 602 603void* ThreadDump(void* data) { 604 dump_thread_t* dump = reinterpret_cast<dump_thread_t*>(data); 605 while (true) { 606 if (android_atomic_acquire_load(dump->now)) { 607 break; 608 } 609 } 610 611 // The status of the actual unwind will be checked elsewhere. 612 dump->backtrace = Backtrace::Create(getpid(), dump->thread.tid); 613 dump->backtrace->Unwind(0); 614 615 android_atomic_acquire_store(1, &dump->done); 616 617 return nullptr; 618} 619 620TEST(libbacktrace, thread_multiple_dump) { 621 // Dump NUM_THREADS simultaneously. 622 std::vector<thread_t> runners(NUM_THREADS); 623 std::vector<dump_thread_t> dumpers(NUM_THREADS); 624 625 pthread_attr_t attr; 626 pthread_attr_init(&attr); 627 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 628 for (size_t i = 0; i < NUM_THREADS; i++) { 629 // Launch the runners, they will spin in hard loops doing nothing. 630 runners[i].tid = 0; 631 runners[i].state = 0; 632 ASSERT_TRUE(pthread_create(&runners[i].threadId, &attr, ThreadMaxRun, &runners[i]) == 0); 633 } 634 635 // Wait for tids to be set. 636 for (std::vector<thread_t>::iterator it = runners.begin(); it != runners.end(); ++it) { 637 ASSERT_TRUE(WaitForNonZero(&it->state, 30)); 638 } 639 640 // Start all of the dumpers at once, they will spin until they are signalled 641 // to begin their dump run. 642 int32_t dump_now = 0; 643 for (size_t i = 0; i < NUM_THREADS; i++) { 644 dumpers[i].thread.tid = runners[i].tid; 645 dumpers[i].thread.state = 0; 646 dumpers[i].done = 0; 647 dumpers[i].now = &dump_now; 648 649 ASSERT_TRUE(pthread_create(&dumpers[i].thread.threadId, &attr, ThreadDump, &dumpers[i]) == 0); 650 } 651 652 // Start all of the dumpers going at once. 653 android_atomic_acquire_store(1, &dump_now); 654 655 for (size_t i = 0; i < NUM_THREADS; i++) { 656 ASSERT_TRUE(WaitForNonZero(&dumpers[i].done, 30)); 657 658 // Tell the runner thread to exit its infinite loop. 659 android_atomic_acquire_store(0, &runners[i].state); 660 661 ASSERT_TRUE(dumpers[i].backtrace != nullptr); 662 VerifyMaxDump(dumpers[i].backtrace); 663 664 delete dumpers[i].backtrace; 665 dumpers[i].backtrace = nullptr; 666 } 667} 668 669TEST(libbacktrace, thread_multiple_dump_same_thread) { 670 pthread_attr_t attr; 671 pthread_attr_init(&attr); 672 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 673 thread_t runner; 674 runner.tid = 0; 675 runner.state = 0; 676 ASSERT_TRUE(pthread_create(&runner.threadId, &attr, ThreadMaxRun, &runner) == 0); 677 678 // Wait for tids to be set. 679 ASSERT_TRUE(WaitForNonZero(&runner.state, 30)); 680 681 // Start all of the dumpers at once, they will spin until they are signalled 682 // to begin their dump run. 683 int32_t dump_now = 0; 684 // Dump the same thread NUM_THREADS simultaneously. 685 std::vector<dump_thread_t> dumpers(NUM_THREADS); 686 for (size_t i = 0; i < NUM_THREADS; i++) { 687 dumpers[i].thread.tid = runner.tid; 688 dumpers[i].thread.state = 0; 689 dumpers[i].done = 0; 690 dumpers[i].now = &dump_now; 691 692 ASSERT_TRUE(pthread_create(&dumpers[i].thread.threadId, &attr, ThreadDump, &dumpers[i]) == 0); 693 } 694 695 // Start all of the dumpers going at once. 696 android_atomic_acquire_store(1, &dump_now); 697 698 for (size_t i = 0; i < NUM_THREADS; i++) { 699 ASSERT_TRUE(WaitForNonZero(&dumpers[i].done, 30)); 700 701 ASSERT_TRUE(dumpers[i].backtrace != nullptr); 702 VerifyMaxDump(dumpers[i].backtrace); 703 704 delete dumpers[i].backtrace; 705 dumpers[i].backtrace = nullptr; 706 } 707 708 // Tell the runner thread to exit its infinite loop. 709 android_atomic_acquire_store(0, &runner.state); 710} 711 712// This test is for UnwindMaps that should share the same map cursor when 713// multiple maps are created for the current process at the same time. 714TEST(libbacktrace, simultaneous_maps) { 715 BacktraceMap* map1 = BacktraceMap::Create(getpid()); 716 BacktraceMap* map2 = BacktraceMap::Create(getpid()); 717 BacktraceMap* map3 = BacktraceMap::Create(getpid()); 718 719 Backtrace* back1 = Backtrace::Create(getpid(), BACKTRACE_CURRENT_THREAD, map1); 720 ASSERT_TRUE(back1 != nullptr); 721 EXPECT_TRUE(back1->Unwind(0)); 722 delete back1; 723 delete map1; 724 725 Backtrace* back2 = Backtrace::Create(getpid(), BACKTRACE_CURRENT_THREAD, map2); 726 ASSERT_TRUE(back2 != nullptr); 727 EXPECT_TRUE(back2->Unwind(0)); 728 delete back2; 729 delete map2; 730 731 Backtrace* back3 = Backtrace::Create(getpid(), BACKTRACE_CURRENT_THREAD, map3); 732 ASSERT_TRUE(back3 != nullptr); 733 EXPECT_TRUE(back3->Unwind(0)); 734 delete back3; 735 delete map3; 736} 737 738TEST(libbacktrace, fillin_erases) { 739 BacktraceMap* back_map = BacktraceMap::Create(getpid()); 740 741 backtrace_map_t map; 742 743 map.start = 1; 744 map.end = 3; 745 map.flags = 1; 746 map.name = "Initialized"; 747 back_map->FillIn(0, &map); 748 delete back_map; 749 750 ASSERT_FALSE(BacktraceMap::IsValid(map)); 751 ASSERT_EQ(static_cast<uintptr_t>(0), map.start); 752 ASSERT_EQ(static_cast<uintptr_t>(0), map.end); 753 ASSERT_EQ(0, map.flags); 754 ASSERT_EQ("", map.name); 755} 756 757TEST(libbacktrace, format_test) { 758 std::unique_ptr<Backtrace> backtrace(Backtrace::Create(getpid(), BACKTRACE_CURRENT_THREAD)); 759 ASSERT_TRUE(backtrace.get() != nullptr); 760 761 backtrace_frame_data_t frame; 762 frame.num = 1; 763 frame.pc = 2; 764 frame.sp = 0; 765 frame.stack_size = 0; 766 frame.func_offset = 0; 767 768 // Check no map set. 769 frame.num = 1; 770#if defined(__LP64__) 771 EXPECT_EQ("#01 pc 0000000000000002 <unknown>", 772#else 773 EXPECT_EQ("#01 pc 00000002 <unknown>", 774#endif 775 backtrace->FormatFrameData(&frame)); 776 777 // Check map name empty, but exists. 778 frame.map.start = 1; 779 frame.map.end = 1; 780 frame.map.load_base = 0; 781#if defined(__LP64__) 782 EXPECT_EQ("#01 pc 0000000000000001 <unknown>", 783#else 784 EXPECT_EQ("#01 pc 00000001 <unknown>", 785#endif 786 backtrace->FormatFrameData(&frame)); 787 788 789 // Check relative pc is set and map name is set. 790 frame.pc = 0x12345679; 791 frame.map.name = "MapFake"; 792 frame.map.start = 1; 793 frame.map.end = 1; 794#if defined(__LP64__) 795 EXPECT_EQ("#01 pc 0000000012345678 MapFake", 796#else 797 EXPECT_EQ("#01 pc 12345678 MapFake", 798#endif 799 backtrace->FormatFrameData(&frame)); 800 801 // Check func_name is set, but no func offset. 802 frame.func_name = "ProcFake"; 803#if defined(__LP64__) 804 EXPECT_EQ("#01 pc 0000000012345678 MapFake (ProcFake)", 805#else 806 EXPECT_EQ("#01 pc 12345678 MapFake (ProcFake)", 807#endif 808 backtrace->FormatFrameData(&frame)); 809 810 // Check func_name is set, and func offset is non-zero. 811 frame.func_offset = 645; 812#if defined(__LP64__) 813 EXPECT_EQ("#01 pc 0000000012345678 MapFake (ProcFake+645)", 814#else 815 EXPECT_EQ("#01 pc 12345678 MapFake (ProcFake+645)", 816#endif 817 backtrace->FormatFrameData(&frame)); 818 819 // Check func_name is set, func offset is non-zero, and load_base is non-zero. 820 frame.func_offset = 645; 821 frame.map.load_base = 100; 822#if defined(__LP64__) 823 EXPECT_EQ("#01 pc 00000000123456dc MapFake (ProcFake+645)", 824#else 825 EXPECT_EQ("#01 pc 123456dc MapFake (ProcFake+645)", 826#endif 827 backtrace->FormatFrameData(&frame)); 828} 829 830struct map_test_t { 831 uintptr_t start; 832 uintptr_t end; 833}; 834 835bool map_sort(map_test_t i, map_test_t j) { 836 return i.start < j.start; 837} 838 839void VerifyMap(pid_t pid) { 840 char buffer[4096]; 841 snprintf(buffer, sizeof(buffer), "/proc/%d/maps", pid); 842 843 FILE* map_file = fopen(buffer, "r"); 844 ASSERT_TRUE(map_file != nullptr); 845 std::vector<map_test_t> test_maps; 846 while (fgets(buffer, sizeof(buffer), map_file)) { 847 map_test_t map; 848 ASSERT_EQ(2, sscanf(buffer, "%" SCNxPTR "-%" SCNxPTR " ", &map.start, &map.end)); 849 test_maps.push_back(map); 850 } 851 fclose(map_file); 852 std::sort(test_maps.begin(), test_maps.end(), map_sort); 853 854 std::unique_ptr<BacktraceMap> map(BacktraceMap::Create(pid)); 855 856 // Basic test that verifies that the map is in the expected order. 857 std::vector<map_test_t>::const_iterator test_it = test_maps.begin(); 858 for (BacktraceMap::const_iterator it = map->begin(); it != map->end(); ++it) { 859 ASSERT_TRUE(test_it != test_maps.end()); 860 ASSERT_EQ(test_it->start, it->start); 861 ASSERT_EQ(test_it->end, it->end); 862 ++test_it; 863 } 864 ASSERT_TRUE(test_it == test_maps.end()); 865} 866 867TEST(libbacktrace, verify_map_remote) { 868 pid_t pid; 869 870 if ((pid = fork()) == 0) { 871 while (true) { 872 } 873 _exit(0); 874 } 875 ASSERT_LT(0, pid); 876 877 ASSERT_TRUE(ptrace(PTRACE_ATTACH, pid, 0, 0) == 0); 878 879 // Wait for the process to get to a stopping point. 880 WaitForStop(pid); 881 882 // The maps should match exactly since the forked process has been paused. 883 VerifyMap(pid); 884 885 ASSERT_TRUE(ptrace(PTRACE_DETACH, pid, 0, 0) == 0); 886 887 kill(pid, SIGKILL); 888 ASSERT_EQ(waitpid(pid, nullptr, 0), pid); 889} 890 891void InitMemory(uint8_t* memory, size_t bytes) { 892 for (size_t i = 0; i < bytes; i++) { 893 memory[i] = i; 894 if (memory[i] == '\0') { 895 // Don't use '\0' in our data so we can verify that an overread doesn't 896 // occur by using a '\0' as the character after the read data. 897 memory[i] = 23; 898 } 899 } 900} 901 902void* ThreadReadTest(void* data) { 903 thread_t* thread_data = reinterpret_cast<thread_t*>(data); 904 905 thread_data->tid = gettid(); 906 907 // Create two map pages. 908 // Mark the second page as not-readable. 909 size_t pagesize = static_cast<size_t>(sysconf(_SC_PAGE_SIZE)); 910 uint8_t* memory; 911 if (posix_memalign(reinterpret_cast<void**>(&memory), pagesize, 2 * pagesize) != 0) { 912 return reinterpret_cast<void*>(-1); 913 } 914 915 if (mprotect(&memory[pagesize], pagesize, PROT_NONE) != 0) { 916 return reinterpret_cast<void*>(-1); 917 } 918 919 // Set up a simple pattern in memory. 920 InitMemory(memory, pagesize); 921 922 thread_data->data = memory; 923 924 // Tell the caller it's okay to start reading memory. 925 android_atomic_acquire_store(1, &thread_data->state); 926 927 // Loop waiting for the caller to finish reading the memory. 928 while (thread_data->state) { 929 } 930 931 // Re-enable read-write on the page so that we don't crash if we try 932 // and access data on this page when freeing the memory. 933 if (mprotect(&memory[pagesize], pagesize, PROT_READ | PROT_WRITE) != 0) { 934 return reinterpret_cast<void*>(-1); 935 } 936 free(memory); 937 938 android_atomic_acquire_store(1, &thread_data->state); 939 940 return nullptr; 941} 942 943void RunReadTest(Backtrace* backtrace, uintptr_t read_addr) { 944 size_t pagesize = static_cast<size_t>(sysconf(_SC_PAGE_SIZE)); 945 946 // Create a page of data to use to do quick compares. 947 uint8_t* expected = new uint8_t[pagesize]; 948 InitMemory(expected, pagesize); 949 950 uint8_t* data = new uint8_t[2*pagesize]; 951 // Verify that we can only read one page worth of data. 952 size_t bytes_read = backtrace->Read(read_addr, data, 2 * pagesize); 953 ASSERT_EQ(pagesize, bytes_read); 954 ASSERT_TRUE(memcmp(data, expected, pagesize) == 0); 955 956 // Verify unaligned reads. 957 for (size_t i = 1; i < sizeof(word_t); i++) { 958 bytes_read = backtrace->Read(read_addr + i, data, 2 * sizeof(word_t)); 959 ASSERT_EQ(2 * sizeof(word_t), bytes_read); 960 ASSERT_TRUE(memcmp(data, &expected[i], 2 * sizeof(word_t)) == 0) 961 << "Offset at " << i << " failed"; 962 } 963 964 // Verify small unaligned reads. 965 for (size_t i = 1; i < sizeof(word_t); i++) { 966 for (size_t j = 1; j < sizeof(word_t); j++) { 967 // Set one byte past what we expect to read, to guarantee we don't overread. 968 data[j] = '\0'; 969 bytes_read = backtrace->Read(read_addr + i, data, j); 970 ASSERT_EQ(j, bytes_read); 971 ASSERT_TRUE(memcmp(data, &expected[i], j) == 0) 972 << "Offset at " << i << " length " << j << " miscompared"; 973 ASSERT_EQ('\0', data[j]) 974 << "Offset at " << i << " length " << j << " wrote too much data"; 975 } 976 } 977 delete[] data; 978 delete[] expected; 979} 980 981TEST(libbacktrace, thread_read) { 982 pthread_attr_t attr; 983 pthread_attr_init(&attr); 984 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 985 pthread_t thread; 986 thread_t thread_data = { 0, 0, 0, nullptr }; 987 ASSERT_TRUE(pthread_create(&thread, &attr, ThreadReadTest, &thread_data) == 0); 988 989 ASSERT_TRUE(WaitForNonZero(&thread_data.state, 10)); 990 991 std::unique_ptr<Backtrace> backtrace(Backtrace::Create(getpid(), thread_data.tid)); 992 ASSERT_TRUE(backtrace.get() != nullptr); 993 994 RunReadTest(backtrace.get(), reinterpret_cast<uintptr_t>(thread_data.data)); 995 996 android_atomic_acquire_store(0, &thread_data.state); 997 998 ASSERT_TRUE(WaitForNonZero(&thread_data.state, 10)); 999} 1000 1001volatile uintptr_t g_ready = 0; 1002volatile uintptr_t g_addr = 0; 1003 1004void ForkedReadTest() { 1005 // Create two map pages. 1006 size_t pagesize = static_cast<size_t>(sysconf(_SC_PAGE_SIZE)); 1007 uint8_t* memory; 1008 if (posix_memalign(reinterpret_cast<void**>(&memory), pagesize, 2 * pagesize) != 0) { 1009 perror("Failed to allocate memory\n"); 1010 exit(1); 1011 } 1012 1013 // Mark the second page as not-readable. 1014 if (mprotect(&memory[pagesize], pagesize, PROT_NONE) != 0) { 1015 perror("Failed to mprotect memory\n"); 1016 exit(1); 1017 } 1018 1019 // Set up a simple pattern in memory. 1020 InitMemory(memory, pagesize); 1021 1022 g_addr = reinterpret_cast<uintptr_t>(memory); 1023 g_ready = 1; 1024 1025 while (1) { 1026 usleep(US_PER_MSEC); 1027 } 1028} 1029 1030TEST(libbacktrace, process_read) { 1031 g_ready = 0; 1032 pid_t pid; 1033 if ((pid = fork()) == 0) { 1034 ForkedReadTest(); 1035 exit(0); 1036 } 1037 ASSERT_NE(-1, pid); 1038 1039 bool test_executed = false; 1040 uint64_t start = NanoTime(); 1041 while (1) { 1042 if (ptrace(PTRACE_ATTACH, pid, 0, 0) == 0) { 1043 WaitForStop(pid); 1044 1045 std::unique_ptr<Backtrace> backtrace(Backtrace::Create(pid, pid)); 1046 ASSERT_TRUE(backtrace.get() != nullptr); 1047 1048 uintptr_t read_addr; 1049 size_t bytes_read = backtrace->Read(reinterpret_cast<uintptr_t>(&g_ready), 1050 reinterpret_cast<uint8_t*>(&read_addr), 1051 sizeof(uintptr_t)); 1052 ASSERT_EQ(sizeof(uintptr_t), bytes_read); 1053 if (read_addr) { 1054 // The forked process is ready to be read. 1055 bytes_read = backtrace->Read(reinterpret_cast<uintptr_t>(&g_addr), 1056 reinterpret_cast<uint8_t*>(&read_addr), 1057 sizeof(uintptr_t)); 1058 ASSERT_EQ(sizeof(uintptr_t), bytes_read); 1059 1060 RunReadTest(backtrace.get(), read_addr); 1061 1062 test_executed = true; 1063 break; 1064 } 1065 ASSERT_TRUE(ptrace(PTRACE_DETACH, pid, 0, 0) == 0); 1066 } 1067 if ((NanoTime() - start) > 5 * NS_PER_SEC) { 1068 break; 1069 } 1070 usleep(US_PER_MSEC); 1071 } 1072 kill(pid, SIGKILL); 1073 ASSERT_EQ(waitpid(pid, nullptr, 0), pid); 1074 1075 ASSERT_TRUE(test_executed); 1076} 1077 1078void VerifyFunctionsFound(const std::vector<std::string>& found_functions) { 1079 // We expect to find these functions in libbacktrace_test. If we don't 1080 // find them, that's a bug in the memory read handling code in libunwind. 1081 std::list<std::string> expected_functions; 1082 expected_functions.push_back("test_recursive_call"); 1083 expected_functions.push_back("test_level_one"); 1084 expected_functions.push_back("test_level_two"); 1085 expected_functions.push_back("test_level_three"); 1086 expected_functions.push_back("test_level_four"); 1087 for (const auto& found_function : found_functions) { 1088 for (const auto& expected_function : expected_functions) { 1089 if (found_function == expected_function) { 1090 expected_functions.remove(found_function); 1091 break; 1092 } 1093 } 1094 } 1095 ASSERT_TRUE(expected_functions.empty()) << "Not all functions found in shared library."; 1096} 1097 1098const char* CopySharedLibrary() { 1099#if defined(__LP64__) 1100 const char* lib_name = "lib64"; 1101#else 1102 const char* lib_name = "lib"; 1103#endif 1104 1105#if defined(__BIONIC__) 1106 const char* tmp_so_name = "/data/local/tmp/libbacktrace_test.so"; 1107 std::string cp_cmd = android::base::StringPrintf("cp /system/%s/libbacktrace_test.so %s", 1108 lib_name, tmp_so_name); 1109#else 1110 const char* tmp_so_name = "/tmp/libbacktrace_test.so"; 1111 if (getenv("ANDROID_HOST_OUT") == NULL) { 1112 fprintf(stderr, "ANDROID_HOST_OUT not set, make sure you run lunch."); 1113 return nullptr; 1114 } 1115 std::string cp_cmd = android::base::StringPrintf("cp %s/%s/libbacktrace_test.so %s", 1116 getenv("ANDROID_HOST_OUT"), lib_name, 1117 tmp_so_name); 1118#endif 1119 1120 // Copy the shared so to a tempory directory. 1121 system(cp_cmd.c_str()); 1122 1123 return tmp_so_name; 1124} 1125 1126TEST(libbacktrace, check_unreadable_elf_local) { 1127 const char* tmp_so_name = CopySharedLibrary(); 1128 ASSERT_TRUE(tmp_so_name != nullptr); 1129 1130 struct stat buf; 1131 ASSERT_TRUE(stat(tmp_so_name, &buf) != -1); 1132 uintptr_t map_size = buf.st_size; 1133 1134 int fd = open(tmp_so_name, O_RDONLY); 1135 ASSERT_TRUE(fd != -1); 1136 1137 void* map = mmap(NULL, map_size, PROT_READ, MAP_PRIVATE, fd, 0); 1138 ASSERT_TRUE(map != MAP_FAILED); 1139 close(fd); 1140 ASSERT_TRUE(unlink(tmp_so_name) != -1); 1141 1142 std::vector<std::string> found_functions; 1143 std::unique_ptr<Backtrace> backtrace(Backtrace::Create(BACKTRACE_CURRENT_PROCESS, 1144 BACKTRACE_CURRENT_THREAD)); 1145 ASSERT_TRUE(backtrace.get() != nullptr); 1146 1147 // Needed before GetFunctionName will work. 1148 backtrace->Unwind(0); 1149 1150 // Loop through the entire map, and get every function we can find. 1151 map_size += reinterpret_cast<uintptr_t>(map); 1152 std::string last_func; 1153 for (uintptr_t read_addr = reinterpret_cast<uintptr_t>(map); 1154 read_addr < map_size; read_addr += 4) { 1155 uintptr_t offset; 1156 std::string func_name = backtrace->GetFunctionName(read_addr, &offset); 1157 if (!func_name.empty() && last_func != func_name) { 1158 found_functions.push_back(func_name); 1159 } 1160 last_func = func_name; 1161 } 1162 1163 ASSERT_TRUE(munmap(map, map_size - reinterpret_cast<uintptr_t>(map)) == 0); 1164 1165 VerifyFunctionsFound(found_functions); 1166} 1167 1168TEST(libbacktrace, check_unreadable_elf_remote) { 1169 const char* tmp_so_name = CopySharedLibrary(); 1170 ASSERT_TRUE(tmp_so_name != nullptr); 1171 1172 g_ready = 0; 1173 1174 struct stat buf; 1175 ASSERT_TRUE(stat(tmp_so_name, &buf) != -1); 1176 uintptr_t map_size = buf.st_size; 1177 1178 pid_t pid; 1179 if ((pid = fork()) == 0) { 1180 int fd = open(tmp_so_name, O_RDONLY); 1181 if (fd == -1) { 1182 fprintf(stderr, "Failed to open file %s: %s\n", tmp_so_name, strerror(errno)); 1183 unlink(tmp_so_name); 1184 exit(0); 1185 } 1186 1187 void* map = mmap(NULL, map_size, PROT_READ, MAP_PRIVATE, fd, 0); 1188 if (map == MAP_FAILED) { 1189 fprintf(stderr, "Failed to map in memory: %s\n", strerror(errno)); 1190 unlink(tmp_so_name); 1191 exit(0); 1192 } 1193 close(fd); 1194 if (unlink(tmp_so_name) == -1) { 1195 fprintf(stderr, "Failed to unlink: %s\n", strerror(errno)); 1196 exit(0); 1197 } 1198 1199 g_addr = reinterpret_cast<uintptr_t>(map); 1200 g_ready = 1; 1201 while (true) { 1202 usleep(US_PER_MSEC); 1203 } 1204 exit(0); 1205 } 1206 ASSERT_TRUE(pid > 0); 1207 1208 std::vector<std::string> found_functions; 1209 uint64_t start = NanoTime(); 1210 while (true) { 1211 ASSERT_TRUE(ptrace(PTRACE_ATTACH, pid, 0, 0) == 0); 1212 1213 // Wait for the process to get to a stopping point. 1214 WaitForStop(pid); 1215 1216 std::unique_ptr<Backtrace> backtrace(Backtrace::Create(pid, BACKTRACE_CURRENT_THREAD)); 1217 ASSERT_TRUE(backtrace.get() != nullptr); 1218 1219 uintptr_t read_addr; 1220 ASSERT_EQ(sizeof(uintptr_t), backtrace->Read(reinterpret_cast<uintptr_t>(&g_ready), reinterpret_cast<uint8_t*>(&read_addr), sizeof(uintptr_t))); 1221 if (read_addr) { 1222 ASSERT_EQ(sizeof(uintptr_t), backtrace->Read(reinterpret_cast<uintptr_t>(&g_addr), reinterpret_cast<uint8_t*>(&read_addr), sizeof(uintptr_t))); 1223 1224 // Needed before GetFunctionName will work. 1225 backtrace->Unwind(0); 1226 1227 // Loop through the entire map, and get every function we can find. 1228 map_size += read_addr; 1229 std::string last_func; 1230 for (; read_addr < map_size; read_addr += 4) { 1231 uintptr_t offset; 1232 std::string func_name = backtrace->GetFunctionName(read_addr, &offset); 1233 if (!func_name.empty() && last_func != func_name) { 1234 found_functions.push_back(func_name); 1235 } 1236 last_func = func_name; 1237 } 1238 break; 1239 } 1240 ASSERT_TRUE(ptrace(PTRACE_DETACH, pid, 0, 0) == 0); 1241 1242 if ((NanoTime() - start) > 5 * NS_PER_SEC) { 1243 break; 1244 } 1245 usleep(US_PER_MSEC); 1246 } 1247 1248 kill(pid, SIGKILL); 1249 ASSERT_EQ(waitpid(pid, nullptr, 0), pid); 1250 1251 VerifyFunctionsFound(found_functions); 1252} 1253 1254bool FindFuncFrameInBacktrace(Backtrace* backtrace, uintptr_t test_func, size_t* frame_num) { 1255 backtrace_map_t map; 1256 backtrace->FillInMap(test_func, &map); 1257 if (!BacktraceMap::IsValid(map)) { 1258 return false; 1259 } 1260 1261 // Loop through the frames, and find the one that is in the map. 1262 *frame_num = 0; 1263 for (Backtrace::const_iterator it = backtrace->begin(); it != backtrace->end(); ++it) { 1264 if (BacktraceMap::IsValid(it->map) && map.start == it->map.start && 1265 it->pc >= test_func) { 1266 *frame_num = it->num; 1267 return true; 1268 } 1269 } 1270 return false; 1271} 1272 1273void VerifyUnreadableElfFrame(Backtrace* backtrace, uintptr_t test_func, size_t frame_num) { 1274 ASSERT_LT(backtrace->NumFrames(), static_cast<size_t>(MAX_BACKTRACE_FRAMES)) 1275 << DumpFrames(backtrace); 1276 1277 ASSERT_TRUE(frame_num != 0) << DumpFrames(backtrace); 1278 // Make sure that there is at least one more frame above the test func call. 1279 ASSERT_LT(frame_num, backtrace->NumFrames()) << DumpFrames(backtrace); 1280 1281 uintptr_t diff = backtrace->GetFrame(frame_num)->pc - test_func; 1282 ASSERT_LT(diff, 200U) << DumpFrames(backtrace); 1283} 1284 1285void VerifyUnreadableElfBacktrace(uintptr_t test_func) { 1286 std::unique_ptr<Backtrace> backtrace(Backtrace::Create(BACKTRACE_CURRENT_PROCESS, 1287 BACKTRACE_CURRENT_THREAD)); 1288 ASSERT_TRUE(backtrace.get() != nullptr); 1289 ASSERT_TRUE(backtrace->Unwind(0)); 1290 1291 size_t frame_num; 1292 ASSERT_TRUE(FindFuncFrameInBacktrace(backtrace.get(), test_func, &frame_num)); 1293 1294 VerifyUnreadableElfFrame(backtrace.get(), test_func, frame_num); 1295} 1296 1297typedef int (*test_func_t)(int, int, int, int, void (*)(uintptr_t), uintptr_t); 1298 1299TEST(libbacktrace, unwind_through_unreadable_elf_local) { 1300 const char* tmp_so_name = CopySharedLibrary(); 1301 ASSERT_TRUE(tmp_so_name != nullptr); 1302 void* lib_handle = dlopen(tmp_so_name, RTLD_NOW); 1303 ASSERT_TRUE(lib_handle != nullptr); 1304 ASSERT_TRUE(unlink(tmp_so_name) != -1); 1305 1306 test_func_t test_func; 1307 test_func = reinterpret_cast<test_func_t>(dlsym(lib_handle, "test_level_one")); 1308 ASSERT_TRUE(test_func != nullptr); 1309 1310 ASSERT_NE(test_func(1, 2, 3, 4, VerifyUnreadableElfBacktrace, 1311 reinterpret_cast<uintptr_t>(test_func)), 0); 1312 1313 ASSERT_TRUE(dlclose(lib_handle) == 0); 1314} 1315 1316TEST(libbacktrace, unwind_through_unreadable_elf_remote) { 1317 const char* tmp_so_name = CopySharedLibrary(); 1318 ASSERT_TRUE(tmp_so_name != nullptr); 1319 void* lib_handle = dlopen(tmp_so_name, RTLD_NOW); 1320 ASSERT_TRUE(lib_handle != nullptr); 1321 ASSERT_TRUE(unlink(tmp_so_name) != -1); 1322 1323 test_func_t test_func; 1324 test_func = reinterpret_cast<test_func_t>(dlsym(lib_handle, "test_level_one")); 1325 ASSERT_TRUE(test_func != nullptr); 1326 1327 pid_t pid; 1328 if ((pid = fork()) == 0) { 1329 test_func(1, 2, 3, 4, 0, 0); 1330 exit(0); 1331 } 1332 ASSERT_TRUE(pid > 0); 1333 ASSERT_TRUE(dlclose(lib_handle) == 0); 1334 1335 uint64_t start = NanoTime(); 1336 bool done = false; 1337 while (!done) { 1338 ASSERT_TRUE(ptrace(PTRACE_ATTACH, pid, 0, 0) == 0); 1339 1340 // Wait for the process to get to a stopping point. 1341 WaitForStop(pid); 1342 1343 std::unique_ptr<Backtrace> backtrace(Backtrace::Create(pid, BACKTRACE_CURRENT_THREAD)); 1344 ASSERT_TRUE(backtrace.get() != nullptr); 1345 ASSERT_TRUE(backtrace->Unwind(0)); 1346 1347 size_t frame_num; 1348 if (FindFuncFrameInBacktrace(backtrace.get(), 1349 reinterpret_cast<uintptr_t>(test_func), &frame_num)) { 1350 1351 VerifyUnreadableElfFrame(backtrace.get(), reinterpret_cast<uintptr_t>(test_func), frame_num); 1352 done = true; 1353 } 1354 1355 ASSERT_TRUE(ptrace(PTRACE_DETACH, pid, 0, 0) == 0); 1356 1357 if ((NanoTime() - start) > 5 * NS_PER_SEC) { 1358 break; 1359 } 1360 usleep(US_PER_MSEC); 1361 } 1362 1363 kill(pid, SIGKILL); 1364 ASSERT_EQ(waitpid(pid, nullptr, 0), pid); 1365 1366 ASSERT_TRUE(done) << "Test function never found in unwind."; 1367} 1368 1369#if defined(ENABLE_PSS_TESTS) 1370#include "GetPss.h" 1371 1372#define MAX_LEAK_BYTES 32*1024UL 1373 1374void CheckForLeak(pid_t pid, pid_t tid) { 1375 // Do a few runs to get the PSS stable. 1376 for (size_t i = 0; i < 100; i++) { 1377 Backtrace* backtrace = Backtrace::Create(pid, tid); 1378 ASSERT_TRUE(backtrace != nullptr); 1379 ASSERT_TRUE(backtrace->Unwind(0)); 1380 delete backtrace; 1381 } 1382 size_t stable_pss = GetPssBytes(); 1383 ASSERT_TRUE(stable_pss != 0); 1384 1385 // Loop enough that even a small leak should be detectable. 1386 for (size_t i = 0; i < 4096; i++) { 1387 Backtrace* backtrace = Backtrace::Create(pid, tid); 1388 ASSERT_TRUE(backtrace != nullptr); 1389 ASSERT_TRUE(backtrace->Unwind(0)); 1390 delete backtrace; 1391 } 1392 size_t new_pss = GetPssBytes(); 1393 ASSERT_TRUE(new_pss != 0); 1394 size_t abs_diff = (new_pss > stable_pss) ? new_pss - stable_pss : stable_pss - new_pss; 1395 // As long as the new pss is within a certain amount, consider everything okay. 1396 ASSERT_LE(abs_diff, MAX_LEAK_BYTES); 1397} 1398 1399TEST(libbacktrace, check_for_leak_local) { 1400 CheckForLeak(BACKTRACE_CURRENT_PROCESS, BACKTRACE_CURRENT_THREAD); 1401} 1402 1403TEST(libbacktrace, check_for_leak_local_thread) { 1404 thread_t thread_data = { 0, 0, 0, nullptr }; 1405 pthread_t thread; 1406 ASSERT_TRUE(pthread_create(&thread, nullptr, ThreadLevelRun, &thread_data) == 0); 1407 1408 // Wait up to 2 seconds for the tid to be set. 1409 ASSERT_TRUE(WaitForNonZero(&thread_data.state, 2)); 1410 1411 CheckForLeak(BACKTRACE_CURRENT_PROCESS, thread_data.tid); 1412 1413 // Tell the thread to exit its infinite loop. 1414 android_atomic_acquire_store(0, &thread_data.state); 1415 1416 ASSERT_TRUE(pthread_join(thread, nullptr) == 0); 1417} 1418 1419TEST(libbacktrace, check_for_leak_remote) { 1420 pid_t pid; 1421 1422 if ((pid = fork()) == 0) { 1423 while (true) { 1424 } 1425 _exit(0); 1426 } 1427 ASSERT_LT(0, pid); 1428 1429 ASSERT_TRUE(ptrace(PTRACE_ATTACH, pid, 0, 0) == 0); 1430 1431 // Wait for the process to get to a stopping point. 1432 WaitForStop(pid); 1433 1434 CheckForLeak(pid, BACKTRACE_CURRENT_THREAD); 1435 1436 ASSERT_TRUE(ptrace(PTRACE_DETACH, pid, 0, 0) == 0); 1437 1438 kill(pid, SIGKILL); 1439 ASSERT_EQ(waitpid(pid, nullptr, 0), pid); 1440} 1441#endif 1442 1443