| /* |
| * Copyright (C) 2015 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #if __linux__ |
| #include <errno.h> |
| #include <signal.h> |
| #include <string.h> |
| #include <sys/ptrace.h> |
| #include <sys/wait.h> |
| #include <unistd.h> |
| #endif |
| |
| #include "jni.h" |
| |
| #include <backtrace/Backtrace.h> |
| #include "android-base/stringprintf.h" |
| |
| #include "base/logging.h" |
| #include "base/macros.h" |
| #include "gc/heap.h" |
| #include "gc/space/image_space.h" |
| #include "oat_file.h" |
| #include "runtime.h" |
| #include "utils.h" |
| |
| namespace art { |
| |
| // For testing debuggerd. We do not have expected-death tests, so can't test this by default. |
| // Code for this is copied from SignalTest. |
| static constexpr bool kCauseSegfault = false; |
| char* go_away_compiler_cfi = nullptr; |
| |
| static void CauseSegfault() { |
| #if defined(__arm__) || defined(__i386__) || defined(__x86_64__) || defined(__aarch64__) |
| // On supported architectures we cause a real SEGV. |
| *go_away_compiler_cfi = 'a'; |
| #else |
| // On other architectures we simulate SEGV. |
| kill(getpid(), SIGSEGV); |
| #endif |
| } |
| |
| extern "C" JNIEXPORT jboolean JNICALL Java_Main_sleep(JNIEnv*, jobject, jint, jboolean, jdouble) { |
| // Keep pausing. |
| printf("Going to sleep\n"); |
| for (;;) { |
| sleep(1); |
| } |
| } |
| |
| // Helper to look for a sequence in the stack trace. |
| #if __linux__ |
| static bool CheckStack(Backtrace* bt, const std::vector<std::string>& seq) { |
| size_t cur_search_index = 0; // The currently active index in seq. |
| CHECK_GT(seq.size(), 0U); |
| |
| for (Backtrace::const_iterator it = bt->begin(); it != bt->end(); ++it) { |
| if (BacktraceMap::IsValid(it->map)) { |
| LOG(INFO) << "Got " << it->func_name << ", looking for " << seq[cur_search_index]; |
| if (it->func_name == seq[cur_search_index]) { |
| cur_search_index++; |
| if (cur_search_index == seq.size()) { |
| return true; |
| } |
| } |
| } |
| } |
| |
| printf("Cannot find %s in backtrace:\n", seq[cur_search_index].c_str()); |
| for (Backtrace::const_iterator it = bt->begin(); it != bt->end(); ++it) { |
| if (BacktraceMap::IsValid(it->map)) { |
| printf(" %s\n", it->func_name.c_str()); |
| } |
| } |
| |
| return false; |
| } |
| |
| static void MoreErrorInfo(pid_t pid, bool sig_quit_on_fail) { |
| printf("Secondary pid is %d\n", pid); |
| |
| PrintFileToLog(android::base::StringPrintf("/proc/%d/maps", pid), ::android::base::ERROR); |
| |
| if (sig_quit_on_fail) { |
| int res = kill(pid, SIGQUIT); |
| if (res != 0) { |
| PLOG(ERROR) << "Failed to send signal"; |
| } |
| } |
| } |
| #endif |
| |
| // Currently we have to fall back to our own loader for the boot image when it's compiled PIC |
| // because its base is zero. Thus in-process unwinding through it won't work. This is a helper |
| // detecting this. |
| #if __linux__ |
| static bool IsPicImage() { |
| std::vector<gc::space::ImageSpace*> image_spaces = |
| Runtime::Current()->GetHeap()->GetBootImageSpaces(); |
| CHECK(!image_spaces.empty()); // We should be running with an image. |
| const OatFile* oat_file = image_spaces[0]->GetOatFile(); |
| CHECK(oat_file != nullptr); // We should have an oat file to go with the image. |
| return oat_file->IsPic(); |
| } |
| #endif |
| |
| extern "C" JNIEXPORT jboolean JNICALL Java_Main_unwindInProcess( |
| JNIEnv*, |
| jobject, |
| jboolean full_signatrues, |
| jint, |
| jboolean) { |
| #if __linux__ |
| if (IsPicImage()) { |
| LOG(INFO) << "Image is pic, in-process unwinding check bypassed."; |
| return JNI_TRUE; |
| } |
| |
| // TODO: What to do on Valgrind? |
| |
| std::unique_ptr<Backtrace> bt(Backtrace::Create(BACKTRACE_CURRENT_PROCESS, GetTid())); |
| if (!bt->Unwind(0, nullptr)) { |
| printf("Cannot unwind in process.\n"); |
| return JNI_FALSE; |
| } else if (bt->NumFrames() == 0) { |
| printf("No frames for unwind in process.\n"); |
| return JNI_FALSE; |
| } |
| |
| // We cannot really parse an exact stack, as the optimizing compiler may inline some functions. |
| // This is also risky, as deduping might play a trick on us, so the test needs to make sure that |
| // only unique functions are being expected. |
| // "mini-debug-info" does not include parameters to save space. |
| std::vector<std::string> seq = { |
| "Java_Main_unwindInProcess", // This function. |
| "Main.unwindInProcess", // The corresponding Java native method frame. |
| "int java.util.Arrays.binarySearch(java.lang.Object[], int, int, java.lang.Object, java.util.Comparator)", // Framework method. |
| "Main.main" // The Java entry method. |
| }; |
| std::vector<std::string> full_seq = { |
| "Java_Main_unwindInProcess", // This function. |
| "boolean Main.unwindInProcess(boolean, int, boolean)", // The corresponding Java native method frame. |
| "int java.util.Arrays.binarySearch(java.lang.Object[], int, int, java.lang.Object, java.util.Comparator)", // Framework method. |
| "void Main.main(java.lang.String[])" // The Java entry method. |
| }; |
| |
| bool result = CheckStack(bt.get(), full_signatrues ? full_seq : seq); |
| if (!kCauseSegfault) { |
| return result ? JNI_TRUE : JNI_FALSE; |
| } else { |
| LOG(INFO) << "Result of check-stack: " << result; |
| } |
| #endif |
| |
| if (kCauseSegfault) { |
| CauseSegfault(); |
| } |
| |
| return JNI_FALSE; |
| } |
| |
| #if __linux__ |
| static constexpr int kSleepTimeMicroseconds = 50000; // 0.05 seconds |
| static constexpr int kMaxTotalSleepTimeMicroseconds = 1000000; // 1 second |
| |
| // Wait for a sigstop. This code is copied from libbacktrace. |
| int wait_for_sigstop(pid_t tid, int* total_sleep_time_usec, bool* detach_failed ATTRIBUTE_UNUSED) { |
| for (;;) { |
| int status; |
| pid_t n = TEMP_FAILURE_RETRY(waitpid(tid, &status, __WALL | WNOHANG)); |
| if (n == -1) { |
| PLOG(WARNING) << "waitpid failed: tid " << tid; |
| break; |
| } else if (n == tid) { |
| if (WIFSTOPPED(status)) { |
| return WSTOPSIG(status); |
| } else { |
| PLOG(ERROR) << "unexpected waitpid response: n=" << n << ", status=" << std::hex << status; |
| break; |
| } |
| } |
| |
| if (*total_sleep_time_usec > kMaxTotalSleepTimeMicroseconds) { |
| PLOG(WARNING) << "timed out waiting for stop signal: tid=" << tid; |
| break; |
| } |
| |
| usleep(kSleepTimeMicroseconds); |
| *total_sleep_time_usec += kSleepTimeMicroseconds; |
| } |
| |
| return -1; |
| } |
| #endif |
| |
| extern "C" JNIEXPORT jboolean JNICALL Java_Main_unwindOtherProcess( |
| JNIEnv*, |
| jobject, |
| jboolean full_signatrues, |
| jint pid_int) { |
| #if __linux__ |
| // TODO: What to do on Valgrind? |
| pid_t pid = static_cast<pid_t>(pid_int); |
| |
| // OK, this is painful. debuggerd uses ptrace to unwind other processes. |
| |
| if (ptrace(PTRACE_ATTACH, pid, 0, 0)) { |
| // Were not able to attach, bad. |
| printf("Failed to attach to other process.\n"); |
| PLOG(ERROR) << "Failed to attach."; |
| kill(pid, SIGKILL); |
| return JNI_FALSE; |
| } |
| |
| kill(pid, SIGSTOP); |
| |
| bool detach_failed = false; |
| int total_sleep_time_usec = 0; |
| int signal = wait_for_sigstop(pid, &total_sleep_time_usec, &detach_failed); |
| if (signal == -1) { |
| LOG(WARNING) << "wait_for_sigstop failed."; |
| } |
| |
| std::unique_ptr<Backtrace> bt(Backtrace::Create(pid, BACKTRACE_CURRENT_THREAD)); |
| bool result = true; |
| if (!bt->Unwind(0, nullptr)) { |
| printf("Cannot unwind other process.\n"); |
| result = false; |
| } else if (bt->NumFrames() == 0) { |
| printf("No frames for unwind of other process.\n"); |
| result = false; |
| } |
| |
| if (result) { |
| // See comment in unwindInProcess for non-exact stack matching. |
| // "mini-debug-info" does not include parameters to save space. |
| std::vector<std::string> seq = { |
| // "Java_Main_sleep", // The sleep function being executed in the |
| // other runtime. |
| // Note: For some reason, the name isn't |
| // resolved, so don't look for it right now. |
| "Main.sleep", // The corresponding Java native method frame. |
| "int java.util.Arrays.binarySearch(java.lang.Object[], int, int, java.lang.Object, java.util.Comparator)", // Framework method. |
| "Main.main" // The Java entry method. |
| }; |
| std::vector<std::string> full_seq = { |
| // "Java_Main_sleep", // The sleep function being executed in the |
| // other runtime. |
| // Note: For some reason, the name isn't |
| // resolved, so don't look for it right now. |
| "boolean Main.sleep(int, boolean, double)", // The corresponding Java native method frame. |
| "int java.util.Arrays.binarySearch(java.lang.Object[], int, int, java.lang.Object, java.util.Comparator)", // Framework method. |
| "void Main.main(java.lang.String[])" // The Java entry method. |
| }; |
| |
| result = CheckStack(bt.get(), full_signatrues ? full_seq : seq); |
| } |
| |
| constexpr bool kSigQuitOnFail = true; |
| if (!result) { |
| MoreErrorInfo(pid, kSigQuitOnFail); |
| } |
| |
| if (ptrace(PTRACE_DETACH, pid, 0, 0) != 0) { |
| PLOG(ERROR) << "Detach failed"; |
| } |
| |
| // If we failed to unwind and induced an ANR dump, give the child some time (20s). |
| if (!result && kSigQuitOnFail) { |
| sleep(20); |
| } |
| |
| // Kill the other process once we are done with it. |
| kill(pid, SIGKILL); |
| |
| return result ? JNI_TRUE : JNI_FALSE; |
| #else |
| UNUSED(pid_int); |
| return JNI_FALSE; |
| #endif |
| } |
| |
| } // namespace art |