diff --git a/debuggerd/Android.bp b/debuggerd/Android.bp index 5565cfdd7..42c30233d 100644 --- a/debuggerd/Android.bp +++ b/debuggerd/Android.bp @@ -7,6 +7,7 @@ cc_defaults { "-Wno-nullability-completeness", "-Os", ], + cpp_std: "experimental", local_include_dirs: ["include"], } diff --git a/debuggerd/crash_dump.cpp b/debuggerd/crash_dump.cpp index df7201df3..3ca9c9224 100644 --- a/debuggerd/crash_dump.cpp +++ b/debuggerd/crash_dump.cpp @@ -95,11 +95,6 @@ static bool ptrace_seize_thread(int pid_proc_fd, pid_t tid, std::string* error) return false; } - // Put the task into ptrace-stop state. - if (ptrace(PTRACE_INTERRUPT, tid, 0, 0) != 0) { - PLOG(FATAL) << "failed to interrupt thread " << tid; - } - return true; } @@ -284,36 +279,38 @@ int main(int argc, char** argv) { // Die if we take too long. alarm(2); + std::string process_name = get_process_name(main_tid); std::string attach_error; std::map threads; { - ATRACE_NAME("ptrace"); + ATRACE_NAME("ptrace_interrupt"); + // Seize the main thread. if (!ptrace_seize_thread(target_proc_fd, main_tid, &attach_error)) { LOG(FATAL) << attach_error; } - // Seize the siblings. - { - std::set siblings; - if (!android::procinfo::GetProcessTids(target, &siblings)) { - PLOG(FATAL) << "failed to get process siblings"; - } + threads.emplace(main_tid, get_thread_name(main_tid)); - // but not the already attached main thread. - siblings.erase(main_tid); - // or the handler pseudothread. - siblings.erase(pseudothread_tid); + // Seize its siblings. + std::set siblings; + if (!android::procinfo::GetProcessTids(target, &siblings)) { + PLOG(FATAL) << "failed to get process siblings"; + } - for (pid_t sibling_tid : siblings) { - if (!ptrace_seize_thread(target_proc_fd, sibling_tid, &attach_error)) { - LOG(WARNING) << attach_error; - } else { - threads.emplace(sibling_tid, get_thread_name(sibling_tid)); - } + // but not the already attached main thread. + siblings.erase(main_tid); + // or the handler pseudothread. + siblings.erase(pseudothread_tid); + + for (pid_t sibling_tid : siblings) { + if (!ptrace_seize_thread(target_proc_fd, sibling_tid, &attach_error)) { + LOG(WARNING) << attach_error; + continue; } + threads.emplace(sibling_tid, get_thread_name(sibling_tid)); } } @@ -334,9 +331,6 @@ int main(int argc, char** argv) { populate_open_files_list(target, &open_files); } - std::string process_name = get_process_name(main_tid); - threads.emplace(main_tid, get_thread_name(main_tid)); - // Drop our capabilities now that we've attached to the threads we care about. drop_capabilities(); @@ -347,6 +341,16 @@ int main(int argc, char** argv) { tombstoned_connected = tombstoned_connect(target, &tombstoned_socket, &output_fd, dump_type_enum); } + // Pause the threads. + { + ATRACE_NAME("ptrace_interrupt"); + for (const auto& [sibling_tid, _] : threads) { + if (ptrace(PTRACE_INTERRUPT, sibling_tid, 0, 0) != 0) { + PLOG(FATAL) << "failed to interrupt thread " << sibling_tid; + } + } + } + // Write a '\1' to stdout to tell the crashing process to resume. // It also restores the value of PR_SET_DUMPABLE at this point. if (TEMP_FAILURE_RETRY(write(STDOUT_FILENO, "\1", 1)) == -1) {