brintos

brintos / llvm-project-archived public Read only

0
0
Text · 2.1 KiB · e546b38 Raw
74 lines · cpp
1// Test for potential deadlock in LeakSanitizer+AddressSanitizer.2// REQUIRES: leak-detection3//4// RUN: %clangxx_asan -O0 %s -o %t5// RUN: %env_asan_opts=detect_leaks=1 not %run %t 2>&1 | FileCheck %s6 7// FIXME: Hangs for unknown reasons on all platforms. We can re-enable it when8// its either deterministic, or we solve the deadlock between asan and lsan.9// UNSUPPORTED: true10 11/*12 * Purpose: Verify deadlock prevention between ASan error reporting and LSan leak checking.13 * 14 * Test Design:15 * 1. Creates contention scenario between:16 *    - ASan's error reporting (requires lock B -> lock A ordering)17 *    - LSan's leak check (requires lock A -> lock B ordering)18 * 2. Thread timing:19 *    - Main thread: Holds 'in' mutex -> Triggers LSan check (lock A then B) 20 *    - Worker thread: Triggers ASan OOB error (lock B then A via symbolization)21 * 22 * Deadlock Condition (if unfixed):23 * Circular lock dependency forms when:24 * [Main Thread] LSan: lock A -> requests lock B25 * [Worker Thread] ASan: lock B -> requests lock A26 * 27 * Success Criteria: 28 * With proper lock ordering enforcement, watchdog should NOT trigger - test exits with Asan report.29  */30 31#include <mutex>32#include <sanitizer/lsan_interface.h>33#include <stdio.h>34#include <thread>35#include <unistd.h>36 37void Watchdog() {38  // Safety mechanism: Turn infinite deadlock into finite test failure39  sleep(60);40  // Unexpected. "not" in RUN will fail if we reached here.41  _exit(0);42}43 44int main(int argc, char **argv) {45  int arr[1] = {0};46  std::mutex in;47  in.lock();48 49  std::thread w(Watchdog);50  w.detach();51 52  std::thread t([&]() {53    in.unlock();54    /* 55     * Provoke ASan error: ASan's error reporting acquires: 56     * 1. ASan's thread registry lock (B) during the reporting 57     * 2. dl_iterate_phdr lock (A) during symbolization58     */59    // CHECK: SUMMARY: AddressSanitizer: stack-buffer-overflow60    arr[argc] = 1; // Deliberate OOB access61  });62 63  in.lock();64  /* 65   * Critical section: LSan's check acquires: 66   * 1. dl_iterate_phdr lock (A)67   * 2. ASan's thread registry lock (B)68   * before Stop The World.69   */70  __lsan_do_leak_check();71  t.join();72  return 0;73}74