crashpad/client/crashpad_client_linux_test.cc
Joshua Peraza a11243e8f1 linux: add wrappers for send/recvmsg
sendmsg() and recvmsg() are complicated to use. Refactor their usage
into functions with a simpler, tested interface and use those instead.
This also adds CreateCredentialSocketpair() to create a pair of
connected sockets with SO_PASSCRED set. This option should be set
before the possibility of any calls to sendmsg() with the socket pair
to avoid race conditions in properly setting credentials.

Also update the handler to use Strategy::kNoPtrace (which causes the
crash dump to fail without breaking the socket connection) if the
credentials were invalid, which can happen if SO_PASSCRED was set after
the call to sendmsg() or if the sending process does not exist in this
namespace.

Change-Id: Id09f87125540255687a3c35d5bed7fa01ec07cff
Reviewed-on: https://chromium-review.googlesource.com/c/crashpad/crashpad/+/1584639
Reviewed-by: Mark Mentovai <mark@chromium.org>
2019-05-02 20:56:08 +00:00

420 lines
13 KiB
C++

// Copyright 2018 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 "client/crashpad_client.h"
#include <dlfcn.h>
#include <stdlib.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <unistd.h>
#include "base/logging.h"
#include "client/annotation.h"
#include "client/annotation_list.h"
#include "client/crash_report_database.h"
#include "client/simulate_crash.h"
#include "gtest/gtest.h"
#include "snapshot/annotation_snapshot.h"
#include "snapshot/minidump/process_snapshot_minidump.h"
#include "snapshot/sanitized/sanitization_information.h"
#include "test/multiprocess.h"
#include "test/multiprocess_exec.h"
#include "test/scoped_temp_dir.h"
#include "test/test_paths.h"
#include "util/file/file_io.h"
#include "util/file/filesystem.h"
#include "util/linux/exception_handler_client.h"
#include "util/linux/exception_information.h"
#include "util/linux/socket.h"
#include "util/misc/address_types.h"
#include "util/misc/from_pointer_cast.h"
#include "util/posix/signals.h"
#if defined(OS_ANDROID)
#include <android/set_abort_message.h>
#include "dlfcn_internal.h"
// Normally this comes from set_abort_message.h, but only at API level 21.
extern "C" void android_set_abort_message(const char* msg)
__attribute__((weak));
#endif
namespace crashpad {
namespace test {
namespace {
bool HandleCrashSuccessfully(int, siginfo_t*, ucontext_t*) {
return true;
}
TEST(CrashpadClient, SimulateCrash) {
ScopedTempDir temp_dir;
base::FilePath handler_path = TestPaths::Executable().DirName().Append(
FILE_PATH_LITERAL("crashpad_handler"));
crashpad::CrashpadClient client;
ASSERT_TRUE(client.StartHandlerAtCrash(handler_path,
base::FilePath(temp_dir.path()),
base::FilePath(),
"",
std::map<std::string, std::string>(),
std::vector<std::string>()));
auto database =
CrashReportDatabase::InitializeWithoutCreating(temp_dir.path());
ASSERT_TRUE(database);
{
CrashpadClient::SetFirstChanceExceptionHandler(HandleCrashSuccessfully);
CRASHPAD_SIMULATE_CRASH();
std::vector<CrashReportDatabase::Report> reports;
ASSERT_EQ(database->GetPendingReports(&reports),
CrashReportDatabase::kNoError);
EXPECT_EQ(reports.size(), 0u);
reports.clear();
ASSERT_EQ(database->GetCompletedReports(&reports),
CrashReportDatabase::kNoError);
EXPECT_EQ(reports.size(), 0u);
}
{
CrashpadClient::SetFirstChanceExceptionHandler(nullptr);
CRASHPAD_SIMULATE_CRASH();
std::vector<CrashReportDatabase::Report> reports;
ASSERT_EQ(database->GetPendingReports(&reports),
CrashReportDatabase::kNoError);
EXPECT_EQ(reports.size(), 1u);
reports.clear();
ASSERT_EQ(database->GetCompletedReports(&reports),
CrashReportDatabase::kNoError);
EXPECT_EQ(reports.size(), 0u);
}
}
constexpr char kTestAnnotationName[] = "name_of_annotation";
constexpr char kTestAnnotationValue[] = "value_of_annotation";
#if defined(OS_ANDROID)
constexpr char kTestAbortMessage[] = "test abort message";
#endif
void ValidateDump(const CrashReportDatabase::UploadReport* report) {
ProcessSnapshotMinidump minidump_snapshot;
ASSERT_TRUE(minidump_snapshot.Initialize(report->Reader()));
#if defined(OS_ANDROID)
// This part of the test requires Q. The API level on Q devices will be 28
// until the API is finalized, so we can't check API level yet. For now, test
// for the presence of a libc symbol which was introduced in Q.
if (crashpad::internal::Dlsym(RTLD_DEFAULT, "android_fdsan_close_with_tag")) {
const auto& annotations = minidump_snapshot.AnnotationsSimpleMap();
auto abort_message = annotations.find("abort_message");
ASSERT_NE(annotations.end(), abort_message);
EXPECT_EQ(kTestAbortMessage, abort_message->second);
}
#endif
for (const ModuleSnapshot* module : minidump_snapshot.Modules()) {
for (const AnnotationSnapshot& annotation : module->AnnotationObjects()) {
if (static_cast<Annotation::Type>(annotation.type) !=
Annotation::Type::kString) {
continue;
}
if (annotation.name == kTestAnnotationName) {
std::string value(
reinterpret_cast<const char*>(annotation.value.data()),
annotation.value.size());
EXPECT_EQ(value, kTestAnnotationValue);
return;
}
}
}
ADD_FAILURE();
}
CRASHPAD_CHILD_TEST_MAIN(StartHandlerAtCrashChild) {
FileHandle in = StdioFileHandle(StdioStream::kStandardInput);
VMSize temp_dir_length;
CheckedReadFileExactly(in, &temp_dir_length, sizeof(temp_dir_length));
std::string temp_dir(temp_dir_length, '\0');
CheckedReadFileExactly(in, &temp_dir[0], temp_dir_length);
base::FilePath handler_path = TestPaths::Executable().DirName().Append(
FILE_PATH_LITERAL("crashpad_handler"));
crashpad::AnnotationList::Register();
static StringAnnotation<32> test_annotation(kTestAnnotationName);
test_annotation.Set(kTestAnnotationValue);
crashpad::CrashpadClient client;
if (!client.StartHandlerAtCrash(handler_path,
base::FilePath(temp_dir),
base::FilePath(),
"",
std::map<std::string, std::string>(),
std::vector<std::string>())) {
return EXIT_FAILURE;
}
#if defined(OS_ANDROID)
if (android_set_abort_message) {
android_set_abort_message(kTestAbortMessage);
}
#endif
__builtin_trap();
NOTREACHED();
return EXIT_SUCCESS;
}
class StartHandlerAtCrashTest : public MultiprocessExec {
public:
StartHandlerAtCrashTest() : MultiprocessExec() {
SetChildTestMainFunction("StartHandlerAtCrashChild");
SetExpectedChildTerminationBuiltinTrap();
}
private:
void MultiprocessParent() override {
ScopedTempDir temp_dir;
VMSize temp_dir_length = temp_dir.path().value().size();
ASSERT_TRUE(LoggingWriteFile(
WritePipeHandle(), &temp_dir_length, sizeof(temp_dir_length)));
ASSERT_TRUE(LoggingWriteFile(
WritePipeHandle(), temp_dir.path().value().data(), temp_dir_length));
// Wait for child to finish.
CheckedReadFileAtEOF(ReadPipeHandle());
auto database = CrashReportDatabase::Initialize(temp_dir.path());
ASSERT_TRUE(database);
std::vector<CrashReportDatabase::Report> reports;
ASSERT_EQ(database->GetCompletedReports(&reports),
CrashReportDatabase::kNoError);
EXPECT_EQ(reports.size(), 0u);
reports.clear();
ASSERT_EQ(database->GetPendingReports(&reports),
CrashReportDatabase::kNoError);
ASSERT_EQ(reports.size(), 1u);
std::unique_ptr<const CrashReportDatabase::UploadReport> report;
ASSERT_EQ(database->GetReportForUploading(reports[0].uuid, &report),
CrashReportDatabase::kNoError);
ValidateDump(report.get());
}
DISALLOW_COPY_AND_ASSIGN(StartHandlerAtCrashTest);
};
TEST(CrashpadClient, StartHandlerAtCrash) {
StartHandlerAtCrashTest test;
test.Run();
}
// Test state for starting the handler for another process.
class StartHandlerForClientTest {
public:
StartHandlerForClientTest() = default;
~StartHandlerForClientTest() = default;
bool Initialize(bool sanitize) {
sanitize_ = sanitize;
return UnixCredentialSocket::CreateCredentialSocketpair(&client_sock_,
&server_sock_);
}
bool StartHandlerOnDemand() {
char c;
if (!LoggingReadFileExactly(server_sock_.get(), &c, sizeof(c))) {
ADD_FAILURE();
return false;
}
base::FilePath handler_path = TestPaths::Executable().DirName().Append(
FILE_PATH_LITERAL("crashpad_handler"));
CrashpadClient client;
if (!client.StartHandlerForClient(handler_path,
temp_dir_.path(),
base::FilePath(),
"",
std::map<std::string, std::string>(),
std::vector<std::string>(),
server_sock_.get())) {
ADD_FAILURE();
return false;
}
return true;
}
void ExpectReport() {
auto database =
CrashReportDatabase::InitializeWithoutCreating(temp_dir_.path());
ASSERT_TRUE(database);
std::vector<CrashReportDatabase::Report> reports;
ASSERT_EQ(database->GetCompletedReports(&reports),
CrashReportDatabase::kNoError);
EXPECT_EQ(reports.size(), 0u);
reports.clear();
ASSERT_EQ(database->GetPendingReports(&reports),
CrashReportDatabase::kNoError);
if (sanitize_) {
EXPECT_EQ(reports.size(), 0u);
} else {
EXPECT_EQ(reports.size(), 1u);
}
}
bool InstallHandler() {
auto signal_handler = SandboxedHandler::Get();
return signal_handler->Initialize(client_sock_.get(), sanitize_);
}
private:
// A signal handler that defers handler process startup to another, presumably
// more privileged, process.
class SandboxedHandler {
public:
static SandboxedHandler* Get() {
static SandboxedHandler* instance = new SandboxedHandler();
return instance;
}
bool Initialize(FileHandle client_sock, bool sanitize) {
client_sock_ = client_sock;
sanitize_ = sanitize;
return Signals::InstallCrashHandlers(HandleCrash, 0, nullptr);
}
private:
SandboxedHandler() = default;
~SandboxedHandler() = delete;
static void HandleCrash(int signo, siginfo_t* siginfo, void* context) {
auto state = Get();
char c;
CHECK(LoggingWriteFile(state->client_sock_, &c, sizeof(c)));
ExceptionInformation exception_information;
exception_information.siginfo_address =
FromPointerCast<decltype(exception_information.siginfo_address)>(
siginfo);
exception_information.context_address =
FromPointerCast<decltype(exception_information.context_address)>(
context);
exception_information.thread_id = syscall(SYS_gettid);
ExceptionHandlerProtocol::ClientInformation info;
info.exception_information_address =
FromPointerCast<decltype(info.exception_information_address)>(
&exception_information);
SanitizationInformation sanitization_info = {};
if (state->sanitize_) {
info.sanitization_information_address =
FromPointerCast<VMAddress>(&sanitization_info);
// Target a non-module address to prevent a crash dump.
sanitization_info.target_module_address =
FromPointerCast<VMAddress>(&sanitization_info);
}
ExceptionHandlerClient handler_client(state->client_sock_, false);
CHECK_EQ(handler_client.RequestCrashDump(info), 0);
Signals::RestoreHandlerAndReraiseSignalOnReturn(siginfo, nullptr);
}
FileHandle client_sock_;
bool sanitize_;
DISALLOW_COPY_AND_ASSIGN(SandboxedHandler);
};
ScopedTempDir temp_dir_;
ScopedFileHandle client_sock_;
ScopedFileHandle server_sock_;
bool sanitize_;
DISALLOW_COPY_AND_ASSIGN(StartHandlerForClientTest);
};
// Tests starting the handler for a child process.
class StartHandlerForChildTest : public Multiprocess {
public:
StartHandlerForChildTest() = default;
~StartHandlerForChildTest() = default;
bool Initialize(bool sanitize) {
SetExpectedChildTerminationBuiltinTrap();
return test_state_.Initialize(sanitize);
}
private:
void MultiprocessParent() {
ASSERT_TRUE(test_state_.StartHandlerOnDemand());
// Wait for chlid to finish.
CheckedReadFileAtEOF(ReadPipeHandle());
test_state_.ExpectReport();
}
void MultiprocessChild() {
CHECK(test_state_.InstallHandler());
__builtin_trap();
NOTREACHED();
}
StartHandlerForClientTest test_state_;
DISALLOW_COPY_AND_ASSIGN(StartHandlerForChildTest);
};
TEST(CrashpadClient, StartHandlerForChild) {
StartHandlerForChildTest test;
ASSERT_TRUE(test.Initialize(/* sanitize= */ false));
test.Run();
}
TEST(CrashpadClient, SanitizedChild) {
StartHandlerForChildTest test;
ASSERT_TRUE(test.Initialize(/* sanitize= */ true));
test.Run();
}
} // namespace
} // namespace test
} // namespace crashpad