test/137-cfi/cfi.cc - platform/art - Git at Google

 /*
  * 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 <unistd.h>
 #include <sys/ptrace.h>
 #include <sys/wait.h>
 #endif

 #include "jni.h"

 #include <backtrace/Backtrace.h>

 #include "base/logging.h"
 #include "base/macros.h"
 #include "gc/heap.h"
 #include "gc/space/image_space.h"
 #include "oat_file.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 (;;) {
     pause();
   }
 }

 // 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;
 }
 #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);
   }

   if (ptrace(PTRACE_DETACH, pid, 0, 0) != 0) {
     PLOG(ERROR) << "Detach failed";
   }

   // 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
	/*
	* 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 <unistd.h>
	#include <sys/ptrace.h>
	#include <sys/wait.h>
	#endif

	#include "jni.h"

	#include <backtrace/Backtrace.h>

	#include "base/logging.h"
	#include "base/macros.h"
	#include "gc/heap.h"
	#include "gc/space/image_space.h"
	#include "oat_file.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 (;;) {
	pause();
	}
	}

	// 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;
	}
	#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);
	}

	if (ptrace(PTRACE_DETACH, pid, 0, 0) != 0) {
	PLOG(ERROR) << "Detach failed";
	}

	// 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