src/third_party/crashpad/util/linux/ptrace_broker_test.cc - cobalt - Git at Google

 // Copyright 2017 The Crashpad Authors. All rights reserved.
 //
 // 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.

 #include "util/linux/ptrace_broker.h"

 #include <sys/socket.h>
 #include <sys/syscall.h>
 #include <sys/types.h>
 #include <unistd.h>

 #include <utility>

 #include "build/build_config.h"
 #include "gtest/gtest.h"
 #include "test/filesystem.h"
 #include "test/linux/get_tls.h"
 #include "test/multiprocess.h"
 #include "test/scoped_temp_dir.h"
 #include "util/file/file_io.h"
 #include "util/linux/ptrace_client.h"
 #include "util/posix/scoped_mmap.h"
 #include "util/synchronization/semaphore.h"
 #include "util/thread/thread.h"

 namespace crashpad {
 namespace test {
 namespace {

 class ScopedTimeoutThread : public Thread {
  public:
   ScopedTimeoutThread() : join_sem_(0) {}
   ~ScopedTimeoutThread() { EXPECT_TRUE(JoinWithTimeout(5.0)); }

  protected:
   void ThreadMain() override { join_sem_.Signal(); }

  private:
   bool JoinWithTimeout(double timeout) {
     if (!join_sem_.TimedWait(timeout)) {
       return false;
     }
     Join();
     return true;
   }

   Semaphore join_sem_;

   DISALLOW_COPY_AND_ASSIGN(ScopedTimeoutThread);
 };

 class RunBrokerThread : public ScopedTimeoutThread {
  public:
   RunBrokerThread(PtraceBroker* broker)
       : ScopedTimeoutThread(), broker_(broker) {}

   ~RunBrokerThread() {}

  private:
   void ThreadMain() override {
     EXPECT_EQ(broker_->Run(), 0);
     ScopedTimeoutThread::ThreadMain();
   }

   PtraceBroker* broker_;

   DISALLOW_COPY_AND_ASSIGN(RunBrokerThread);
 };

 class BlockOnReadThread : public ScopedTimeoutThread {
  public:
   BlockOnReadThread(int readfd, int writefd)
       : ScopedTimeoutThread(), readfd_(readfd), writefd_(writefd) {}

   ~BlockOnReadThread() {}

  private:
   void ThreadMain() override {
     pid_t pid = syscall(SYS_gettid);
     LoggingWriteFile(writefd_, &pid, sizeof(pid));

     LinuxVMAddress tls = GetTLS();
     LoggingWriteFile(writefd_, &tls, sizeof(tls));

     CheckedReadFileAtEOF(readfd_);
     ScopedTimeoutThread::ThreadMain();
   }

   int readfd_;
   int writefd_;

   DISALLOW_COPY_AND_ASSIGN(BlockOnReadThread);
 };

 class SameBitnessTest : public Multiprocess {
  public:
   SameBitnessTest() : Multiprocess(), mapping_() {}
   ~SameBitnessTest() {}

  protected:
   void PreFork() override {
     ASSERT_NO_FATAL_FAILURE(Multiprocess::PreFork());

     size_t page_size = getpagesize();
     ASSERT_TRUE(mapping_.ResetMmap(nullptr,
                                    page_size * 3,
                                    PROT_READ | PROT_WRITE,
                                    MAP_PRIVATE | MAP_ANON,
                                    -1,
                                    0));
     ASSERT_TRUE(mapping_.ResetAddrLen(mapping_.addr(), page_size * 2));

     auto buffer = mapping_.addr_as<char*>();
     for (size_t index = 0; index < mapping_.len(); ++index) {
       buffer[index] = index % 256;
     }
   }

  private:
   void BrokerTests(bool set_broker_pid,
                    LinuxVMAddress child1_tls,
                    LinuxVMAddress child2_tls,
                    pid_t child2_tid,
                    const base::FilePath& file_dir,
                    const base::FilePath& test_file,
                    const std::string& expected_file_contents) {
     int socks[2];
     ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, socks), 0);
     ScopedFileHandle broker_sock(socks[0]);
     ScopedFileHandle client_sock(socks[1]);

 #if defined(ARCH_CPU_64_BITS)
     constexpr bool am_64_bit = true;
 #else
     constexpr bool am_64_bit = false;
 #endif  // ARCH_CPU_64_BITS

     PtraceBroker broker(
         broker_sock.get(), set_broker_pid ? ChildPID() : -1, am_64_bit);
     RunBrokerThread broker_thread(&broker);
     broker_thread.Start();

     PtraceClient client;
     ASSERT_TRUE(client.Initialize(
         client_sock.get(), ChildPID(), /* try_direct_memory= */ false));

     EXPECT_EQ(client.GetProcessID(), ChildPID());

     std::vector<pid_t> threads;
     ASSERT_TRUE(client.Threads(&threads));
     EXPECT_EQ(threads.size(), 2u);
     if (threads[0] == ChildPID()) {
       EXPECT_EQ(threads[1], child2_tid);
     } else {
       EXPECT_EQ(threads[0], child2_tid);
       EXPECT_EQ(threads[1], ChildPID());
     }

     EXPECT_TRUE(client.Attach(child2_tid));
     EXPECT_EQ(client.Is64Bit(), am_64_bit);

     ThreadInfo info1;
     ASSERT_TRUE(client.GetThreadInfo(ChildPID(), &info1));
     EXPECT_EQ(info1.thread_specific_data_address, child1_tls);

     ThreadInfo info2;
     ASSERT_TRUE(client.GetThreadInfo(child2_tid, &info2));
     EXPECT_EQ(info2.thread_specific_data_address, child2_tls);

     ProcessMemory* memory = client.Memory();
     ASSERT_TRUE(memory);

     auto buffer = std::make_unique<char[]>(mapping_.len());
     ASSERT_TRUE(memory->Read(
         mapping_.addr_as<VMAddress>(), mapping_.len(), buffer.get()));
     auto expected_buffer = mapping_.addr_as<char*>();
     for (size_t index = 0; index < mapping_.len(); ++index) {
       EXPECT_EQ(buffer[index], expected_buffer[index]);
     }

     char first;
     ASSERT_TRUE(
         memory->Read(mapping_.addr_as<VMAddress>(), sizeof(first), &first));
     EXPECT_EQ(first, expected_buffer[0]);

     char last;
     ASSERT_TRUE(memory->Read(mapping_.addr_as<VMAddress>() + mapping_.len() - 1,
                              sizeof(last),
                              &last));
     EXPECT_EQ(last, expected_buffer[mapping_.len() - 1]);

     char unmapped;
     EXPECT_FALSE(memory->Read(mapping_.addr_as<VMAddress>() + mapping_.len(),
                               sizeof(unmapped),
                               &unmapped));

     std::string file_root = file_dir.value() + '/';
     broker.SetFileRoot(file_root.c_str());

     std::string file_contents;
     ASSERT_TRUE(client.ReadFileContents(test_file, &file_contents));
     EXPECT_EQ(file_contents, expected_file_contents);

     ScopedTempDir temp_dir2;
     base::FilePath test_file2(temp_dir2.path().Append("test_file2"));
     ASSERT_TRUE(CreateFile(test_file2));
     EXPECT_FALSE(client.ReadFileContents(test_file2, &file_contents));
   }

   void MultiprocessParent() override {
     LinuxVMAddress child1_tls;
     ASSERT_TRUE(LoggingReadFileExactly(
         ReadPipeHandle(), &child1_tls, sizeof(child1_tls)));

     pid_t child2_tid;
     ASSERT_TRUE(LoggingReadFileExactly(
         ReadPipeHandle(), &child2_tid, sizeof(child2_tid)));

     LinuxVMAddress child2_tls;
     ASSERT_TRUE(LoggingReadFileExactly(
         ReadPipeHandle(), &child2_tls, sizeof(child2_tls)));

     ScopedTempDir temp_dir;
     base::FilePath file_path(temp_dir.path().Append("test_file"));
     std::string expected_file_contents;
     {
       expected_file_contents.resize(4097);
       for (size_t i = 0; i < expected_file_contents.size(); ++i) {
         expected_file_contents[i] = static_cast<char>(i % 256);
       }
       ScopedFileHandle handle(
           LoggingOpenFileForWrite(file_path,
                                   FileWriteMode::kCreateOrFail,
                                   FilePermissions::kWorldReadable));
       ASSERT_TRUE(LoggingWriteFile(handle.get(),
                                    expected_file_contents.data(),
                                    expected_file_contents.size()));
     }

     BrokerTests(true,
                 child1_tls,
                 child2_tls,
                 child2_tid,
                 temp_dir.path(),
                 file_path,
                 expected_file_contents);
     BrokerTests(false,
                 child1_tls,
                 child2_tls,
                 child2_tid,
                 temp_dir.path(),
                 file_path,
                 expected_file_contents);
   }

   void MultiprocessChild() override {
     LinuxVMAddress tls = GetTLS();
     ASSERT_TRUE(LoggingWriteFile(WritePipeHandle(), &tls, sizeof(tls)));

     BlockOnReadThread thread(ReadPipeHandle(), WritePipeHandle());
     thread.Start();

     CheckedReadFileAtEOF(ReadPipeHandle());
   }

   ScopedMmap mapping_;

   DISALLOW_COPY_AND_ASSIGN(SameBitnessTest);
 };

 TEST(PtraceBroker, SameBitness) {
   SameBitnessTest test;
   test.Run();
 }

 // TODO(jperaza): Test against a process with different bitness.

 }  // namespace
 }  // namespace test
 }  // namespace crashpad
	// Copyright 2017 The Crashpad Authors. All rights reserved.
	//
	// 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.

	#include "util/linux/ptrace_broker.h"

	#include <sys/socket.h>
	#include <sys/syscall.h>
	#include <sys/types.h>
	#include <unistd.h>

	#include <utility>

	#include "build/build_config.h"
	#include "gtest/gtest.h"
	#include "test/filesystem.h"
	#include "test/linux/get_tls.h"
	#include "test/multiprocess.h"
	#include "test/scoped_temp_dir.h"
	#include "util/file/file_io.h"
	#include "util/linux/ptrace_client.h"
	#include "util/posix/scoped_mmap.h"
	#include "util/synchronization/semaphore.h"
	#include "util/thread/thread.h"

	namespace crashpad {
	namespace test {
	namespace {

	class ScopedTimeoutThread : public Thread {
	public:
	ScopedTimeoutThread() : join_sem_(0) {}
	~ScopedTimeoutThread() { EXPECT_TRUE(JoinWithTimeout(5.0)); }

	protected:
	void ThreadMain() override { join_sem_.Signal(); }

	private:
	bool JoinWithTimeout(double timeout) {
	if (!join_sem_.TimedWait(timeout)) {
	return false;
	}
	Join();
	return true;
	}

	Semaphore join_sem_;

	DISALLOW_COPY_AND_ASSIGN(ScopedTimeoutThread);
	};

	class RunBrokerThread : public ScopedTimeoutThread {
	public:
	RunBrokerThread(PtraceBroker* broker)
	: ScopedTimeoutThread(), broker_(broker) {}

	~RunBrokerThread() {}

	private:
	void ThreadMain() override {
	EXPECT_EQ(broker_->Run(), 0);
	ScopedTimeoutThread::ThreadMain();
	}

	PtraceBroker* broker_;

	DISALLOW_COPY_AND_ASSIGN(RunBrokerThread);
	};

	class BlockOnReadThread : public ScopedTimeoutThread {
	public:
	BlockOnReadThread(int readfd, int writefd)
	: ScopedTimeoutThread(), readfd_(readfd), writefd_(writefd) {}

	~BlockOnReadThread() {}

	private:
	void ThreadMain() override {
	pid_t pid = syscall(SYS_gettid);
	LoggingWriteFile(writefd_, &pid, sizeof(pid));

	LinuxVMAddress tls = GetTLS();
	LoggingWriteFile(writefd_, &tls, sizeof(tls));

	CheckedReadFileAtEOF(readfd_);
	ScopedTimeoutThread::ThreadMain();
	}

	int readfd_;
	int writefd_;

	DISALLOW_COPY_AND_ASSIGN(BlockOnReadThread);
	};

	class SameBitnessTest : public Multiprocess {
	public:
	SameBitnessTest() : Multiprocess(), mapping_() {}
	~SameBitnessTest() {}

	protected:
	void PreFork() override {
	ASSERT_NO_FATAL_FAILURE(Multiprocess::PreFork());

	size_t page_size = getpagesize();
	ASSERT_TRUE(mapping_.ResetMmap(nullptr,
	page_size * 3,
	PROT_READ \| PROT_WRITE,
	MAP_PRIVATE \| MAP_ANON,
	-1,
	0));
	ASSERT_TRUE(mapping_.ResetAddrLen(mapping_.addr(), page_size * 2));

	auto buffer = mapping_.addr_as<char*>();
	for (size_t index = 0; index < mapping_.len(); ++index) {
	buffer[index] = index % 256;
	}
	}

	private:
	void BrokerTests(bool set_broker_pid,
	LinuxVMAddress child1_tls,
	LinuxVMAddress child2_tls,
	pid_t child2_tid,
	const base::FilePath& file_dir,
	const base::FilePath& test_file,
	const std::string& expected_file_contents) {
	int socks[2];
	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, socks), 0);
	ScopedFileHandle broker_sock(socks[0]);
	ScopedFileHandle client_sock(socks[1]);

	#if defined(ARCH_CPU_64_BITS)
	constexpr bool am_64_bit = true;
	#else
	constexpr bool am_64_bit = false;
	#endif // ARCH_CPU_64_BITS

	PtraceBroker broker(
	broker_sock.get(), set_broker_pid ? ChildPID() : -1, am_64_bit);
	RunBrokerThread broker_thread(&broker);
	broker_thread.Start();

	PtraceClient client;
	ASSERT_TRUE(client.Initialize(
	client_sock.get(), ChildPID(), /* try_direct_memory= */ false));

	EXPECT_EQ(client.GetProcessID(), ChildPID());

	std::vector<pid_t> threads;
	ASSERT_TRUE(client.Threads(&threads));
	EXPECT_EQ(threads.size(), 2u);
	if (threads[0] == ChildPID()) {
	EXPECT_EQ(threads[1], child2_tid);
	} else {
	EXPECT_EQ(threads[0], child2_tid);
	EXPECT_EQ(threads[1], ChildPID());
	}

	EXPECT_TRUE(client.Attach(child2_tid));
	EXPECT_EQ(client.Is64Bit(), am_64_bit);

	ThreadInfo info1;
	ASSERT_TRUE(client.GetThreadInfo(ChildPID(), &info1));
	EXPECT_EQ(info1.thread_specific_data_address, child1_tls);

	ThreadInfo info2;
	ASSERT_TRUE(client.GetThreadInfo(child2_tid, &info2));
	EXPECT_EQ(info2.thread_specific_data_address, child2_tls);

	ProcessMemory* memory = client.Memory();
	ASSERT_TRUE(memory);

	auto buffer = std::make_unique<char[]>(mapping_.len());
	ASSERT_TRUE(memory->Read(
	mapping_.addr_as<VMAddress>(), mapping_.len(), buffer.get()));
	auto expected_buffer = mapping_.addr_as<char*>();
	for (size_t index = 0; index < mapping_.len(); ++index) {
	EXPECT_EQ(buffer[index], expected_buffer[index]);
	}

	char first;
	ASSERT_TRUE(
	memory->Read(mapping_.addr_as<VMAddress>(), sizeof(first), &first));
	EXPECT_EQ(first, expected_buffer[0]);

	char last;
	ASSERT_TRUE(memory->Read(mapping_.addr_as<VMAddress>() + mapping_.len() - 1,
	sizeof(last),
	&last));
	EXPECT_EQ(last, expected_buffer[mapping_.len() - 1]);

	char unmapped;
	EXPECT_FALSE(memory->Read(mapping_.addr_as<VMAddress>() + mapping_.len(),
	sizeof(unmapped),
	&unmapped));

	std::string file_root = file_dir.value() + '/';
	broker.SetFileRoot(file_root.c_str());

	std::string file_contents;
	ASSERT_TRUE(client.ReadFileContents(test_file, &file_contents));
	EXPECT_EQ(file_contents, expected_file_contents);

	ScopedTempDir temp_dir2;
	base::FilePath test_file2(temp_dir2.path().Append("test_file2"));
	ASSERT_TRUE(CreateFile(test_file2));
	EXPECT_FALSE(client.ReadFileContents(test_file2, &file_contents));
	}

	void MultiprocessParent() override {
	LinuxVMAddress child1_tls;
	ASSERT_TRUE(LoggingReadFileExactly(
	ReadPipeHandle(), &child1_tls, sizeof(child1_tls)));

	pid_t child2_tid;
	ASSERT_TRUE(LoggingReadFileExactly(
	ReadPipeHandle(), &child2_tid, sizeof(child2_tid)));

	LinuxVMAddress child2_tls;
	ASSERT_TRUE(LoggingReadFileExactly(
	ReadPipeHandle(), &child2_tls, sizeof(child2_tls)));

	ScopedTempDir temp_dir;
	base::FilePath file_path(temp_dir.path().Append("test_file"));
	std::string expected_file_contents;
	{
	expected_file_contents.resize(4097);
	for (size_t i = 0; i < expected_file_contents.size(); ++i) {
	expected_file_contents[i] = static_cast<char>(i % 256);
	}
	ScopedFileHandle handle(
	LoggingOpenFileForWrite(file_path,
	FileWriteMode::kCreateOrFail,
	FilePermissions::kWorldReadable));
	ASSERT_TRUE(LoggingWriteFile(handle.get(),
	expected_file_contents.data(),
	expected_file_contents.size()));
	}

	BrokerTests(true,
	child1_tls,
	child2_tls,
	child2_tid,
	temp_dir.path(),
	file_path,
	expected_file_contents);
	BrokerTests(false,
	child1_tls,
	child2_tls,
	child2_tid,
	temp_dir.path(),
	file_path,
	expected_file_contents);
	}

	void MultiprocessChild() override {
	LinuxVMAddress tls = GetTLS();
	ASSERT_TRUE(LoggingWriteFile(WritePipeHandle(), &tls, sizeof(tls)));

	BlockOnReadThread thread(ReadPipeHandle(), WritePipeHandle());
	thread.Start();

	CheckedReadFileAtEOF(ReadPipeHandle());
	}

	ScopedMmap mapping_;

	DISALLOW_COPY_AND_ASSIGN(SameBitnessTest);
	};

	TEST(PtraceBroker, SameBitness) {
	SameBitnessTest test;
	test.Run();
	}

	// TODO(jperaza): Test against a process with different bitness.

	} // namespace
	} // namespace test
	} // namespace crashpad