blob: 39d7fff1ca86d2dbf7dfd0c5a837eb7bea062b22 [file] [log] [blame]
/*
* Copyright 2016, 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.
*/
#include <dirent.h>
#include <dlfcn.h>
#include <err.h>
#include <fcntl.h>
#include <linux/prctl.h>
#include <malloc.h>
#include <pthread.h>
#include <stdlib.h>
#include <sys/capability.h>
#include <sys/mman.h>
#include <sys/prctl.h>
#include <sys/ptrace.h>
#include <sys/resource.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <unistd.h>
#include <chrono>
#include <regex>
#include <set>
#include <string>
#include <thread>
#include <android/dlext.h>
#include <android/fdsan.h>
#include <android/set_abort_message.h>
#include <bionic/malloc.h>
#include <bionic/mte.h>
#include <bionic/reserved_signals.h>
#include <android-base/cmsg.h>
#include <android-base/file.h>
#include <android-base/logging.h>
#include <android-base/macros.h>
#include <android-base/parseint.h>
#include <android-base/properties.h>
#include <android-base/stringprintf.h>
#include <android-base/strings.h>
#include <android-base/test_utils.h>
#include <android-base/unique_fd.h>
#include <cutils/sockets.h>
#include <gmock/gmock.h>
#include <gtest/gtest.h>
#include <unwindstack/Elf.h>
#include <unwindstack/Memory.h>
#include <libminijail.h>
#include <scoped_minijail.h>
#include "crash_test.h"
#include "debuggerd/handler.h"
#include "gtest/gtest.h"
#include "libdebuggerd/utility.h"
#include "protocol.h"
#include "tombstoned/tombstoned.h"
#include "util.h"
using namespace std::chrono_literals;
using android::base::SendFileDescriptors;
using android::base::unique_fd;
using ::testing::HasSubstr;
#if defined(__LP64__)
#define ARCH_SUFFIX "64"
#else
#define ARCH_SUFFIX ""
#endif
constexpr char kWaitForDebuggerKey[] = "debug.debuggerd.wait_for_debugger";
#define TIMEOUT(seconds, expr) \
[&]() { \
struct sigaction old_sigaction; \
struct sigaction new_sigaction = {}; \
new_sigaction.sa_handler = [](int) {}; \
if (sigaction(SIGALRM, &new_sigaction, &old_sigaction) != 0) { \
err(1, "sigaction failed"); \
} \
alarm(seconds); \
auto value = expr; \
int saved_errno = errno; \
if (sigaction(SIGALRM, &old_sigaction, nullptr) != 0) { \
err(1, "sigaction failed"); \
} \
alarm(0); \
errno = saved_errno; \
return value; \
}()
// Backtrace frame dump could contain:
// #01 pc 0001cded /data/tmp/debuggerd_test32 (raise_debugger_signal+80)
// or
// #01 pc 00022a09 /data/tmp/debuggerd_test32 (offset 0x12000) (raise_debugger_signal+80)
#define ASSERT_BACKTRACE_FRAME(result, frame_name) \
ASSERT_MATCH(result, \
R"(#\d\d pc [0-9a-f]+\s+ \S+ (\(offset 0x[0-9a-f]+\) )?\()" frame_name R"(\+)");
static void tombstoned_intercept(pid_t target_pid, unique_fd* intercept_fd, unique_fd* output_fd,
InterceptStatus* status, DebuggerdDumpType intercept_type) {
intercept_fd->reset(socket_local_client(kTombstonedInterceptSocketName,
ANDROID_SOCKET_NAMESPACE_RESERVED, SOCK_SEQPACKET));
if (intercept_fd->get() == -1) {
FAIL() << "failed to contact tombstoned: " << strerror(errno);
}
InterceptRequest req = {
.dump_type = intercept_type,
.pid = target_pid,
};
unique_fd output_pipe_write;
if (!Pipe(output_fd, &output_pipe_write)) {
FAIL() << "failed to create output pipe: " << strerror(errno);
}
std::string pipe_size_str;
int pipe_buffer_size;
if (!android::base::ReadFileToString("/proc/sys/fs/pipe-max-size", &pipe_size_str)) {
FAIL() << "failed to read /proc/sys/fs/pipe-max-size: " << strerror(errno);
}
pipe_size_str = android::base::Trim(pipe_size_str);
if (!android::base::ParseInt(pipe_size_str.c_str(), &pipe_buffer_size, 0)) {
FAIL() << "failed to parse pipe max size";
}
if (fcntl(output_fd->get(), F_SETPIPE_SZ, pipe_buffer_size) != pipe_buffer_size) {
FAIL() << "failed to set pipe size: " << strerror(errno);
}
ASSERT_GE(pipe_buffer_size, 1024 * 1024);
ssize_t rc = SendFileDescriptors(intercept_fd->get(), &req, sizeof(req), output_pipe_write.get());
output_pipe_write.reset();
if (rc != sizeof(req)) {
FAIL() << "failed to send output fd to tombstoned: " << strerror(errno);
}
InterceptResponse response;
rc = TEMP_FAILURE_RETRY(read(intercept_fd->get(), &response, sizeof(response)));
if (rc == -1) {
FAIL() << "failed to read response from tombstoned: " << strerror(errno);
} else if (rc == 0) {
FAIL() << "failed to read response from tombstoned (EOF)";
} else if (rc != sizeof(response)) {
FAIL() << "received packet of unexpected length from tombstoned: expected " << sizeof(response)
<< ", received " << rc;
}
*status = response.status;
}
static bool pac_supported() {
#if defined(__aarch64__)
return getauxval(AT_HWCAP) & HWCAP_PACA;
#else
return false;
#endif
}
class CrasherTest : public ::testing::Test {
public:
pid_t crasher_pid = -1;
bool previous_wait_for_debugger;
unique_fd crasher_pipe;
unique_fd intercept_fd;
CrasherTest();
~CrasherTest();
void StartIntercept(unique_fd* output_fd, DebuggerdDumpType intercept_type = kDebuggerdTombstone);
// Returns -1 if we fail to read a response from tombstoned, otherwise the received return code.
void FinishIntercept(int* result);
void StartProcess(std::function<void()> function, std::function<pid_t()> forker = fork);
void StartCrasher(const std::string& crash_type);
void FinishCrasher();
void AssertDeath(int signo);
static void Trap(void* ptr);
};
CrasherTest::CrasherTest() {
previous_wait_for_debugger = android::base::GetBoolProperty(kWaitForDebuggerKey, false);
android::base::SetProperty(kWaitForDebuggerKey, "0");
// Clear the old property too, just in case someone's been using it
// on this device. (We only document the new name, but we still support
// the old name so we don't break anyone's existing setups.)
android::base::SetProperty("debug.debuggerd.wait_for_gdb", "0");
}
CrasherTest::~CrasherTest() {
if (crasher_pid != -1) {
kill(crasher_pid, SIGKILL);
int status;
TEMP_FAILURE_RETRY(waitpid(crasher_pid, &status, WUNTRACED));
}
android::base::SetProperty(kWaitForDebuggerKey, previous_wait_for_debugger ? "1" : "0");
}
void CrasherTest::StartIntercept(unique_fd* output_fd, DebuggerdDumpType intercept_type) {
if (crasher_pid == -1) {
FAIL() << "crasher hasn't been started";
}
InterceptStatus status;
tombstoned_intercept(crasher_pid, &this->intercept_fd, output_fd, &status, intercept_type);
ASSERT_EQ(InterceptStatus::kRegistered, status);
}
void CrasherTest::FinishIntercept(int* result) {
InterceptResponse response;
ssize_t rc = TIMEOUT(30, read(intercept_fd.get(), &response, sizeof(response)));
if (rc == -1) {
FAIL() << "failed to read response from tombstoned: " << strerror(errno);
} else if (rc == 0) {
*result = -1;
} else if (rc != sizeof(response)) {
FAIL() << "received packet of unexpected length from tombstoned: expected " << sizeof(response)
<< ", received " << rc;
} else {
*result = response.status == InterceptStatus::kStarted ? 1 : 0;
}
}
void CrasherTest::StartProcess(std::function<void()> function, std::function<pid_t()> forker) {
unique_fd read_pipe;
unique_fd crasher_read_pipe;
if (!Pipe(&crasher_read_pipe, &crasher_pipe)) {
FAIL() << "failed to create pipe: " << strerror(errno);
}
crasher_pid = forker();
if (crasher_pid == -1) {
FAIL() << "fork failed: " << strerror(errno);
} else if (crasher_pid == 0) {
char dummy;
crasher_pipe.reset();
TEMP_FAILURE_RETRY(read(crasher_read_pipe.get(), &dummy, 1));
function();
_exit(0);
}
}
void CrasherTest::FinishCrasher() {
if (crasher_pipe == -1) {
FAIL() << "crasher pipe uninitialized";
}
ssize_t rc = TEMP_FAILURE_RETRY(write(crasher_pipe.get(), "\n", 1));
if (rc == -1) {
FAIL() << "failed to write to crasher pipe: " << strerror(errno);
} else if (rc == 0) {
FAIL() << "crasher pipe was closed";
}
}
void CrasherTest::AssertDeath(int signo) {
int status;
pid_t pid = TIMEOUT(30, waitpid(crasher_pid, &status, 0));
if (pid != crasher_pid) {
printf("failed to wait for crasher (expected pid %d, return value %d): %s\n", crasher_pid, pid,
strerror(errno));
sleep(100);
FAIL() << "failed to wait for crasher: " << strerror(errno);
}
if (signo == 0) {
ASSERT_TRUE(WIFEXITED(status)) << "Terminated due to unexpected signal " << WTERMSIG(status);
ASSERT_EQ(0, WEXITSTATUS(signo));
} else {
ASSERT_FALSE(WIFEXITED(status));
ASSERT_TRUE(WIFSIGNALED(status)) << "crasher didn't terminate via a signal";
ASSERT_EQ(signo, WTERMSIG(status));
}
crasher_pid = -1;
}
static void ConsumeFd(unique_fd fd, std::string* output) {
constexpr size_t read_length = PAGE_SIZE;
std::string result;
while (true) {
size_t offset = result.size();
result.resize(result.size() + PAGE_SIZE);
ssize_t rc = TEMP_FAILURE_RETRY(read(fd.get(), &result[offset], read_length));
if (rc == -1) {
FAIL() << "read failed: " << strerror(errno);
} else if (rc == 0) {
result.resize(result.size() - PAGE_SIZE);
break;
}
result.resize(result.size() - PAGE_SIZE + rc);
}
*output = std::move(result);
}
class LogcatCollector {
public:
LogcatCollector() { system("logcat -c"); }
void Collect(std::string* output) {
FILE* cmd_stdout = popen("logcat -d '*:S DEBUG'", "r");
ASSERT_NE(cmd_stdout, nullptr);
unique_fd tmp_fd(TEMP_FAILURE_RETRY(dup(fileno(cmd_stdout))));
ConsumeFd(std::move(tmp_fd), output);
pclose(cmd_stdout);
}
};
TEST_F(CrasherTest, smoke) {
int intercept_result;
unique_fd output_fd;
StartProcess([]() {
*reinterpret_cast<volatile char*>(0xdead) = '1';
});
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGSEGV);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
#ifdef __LP64__
ASSERT_MATCH(result,
R"(signal 11 \(SIGSEGV\), code 1 \(SEGV_MAPERR\), fault addr 0x000000000000dead)");
#else
ASSERT_MATCH(result, R"(signal 11 \(SIGSEGV\), code 1 \(SEGV_MAPERR\), fault addr 0x0000dead)");
#endif
if (mte_supported()) {
// Test that the default TAGGED_ADDR_CTRL value is set.
ASSERT_MATCH(result, R"(tagged_addr_ctrl: 000000000007fff3)"
R"( \(PR_TAGGED_ADDR_ENABLE, PR_MTE_TCF_SYNC, mask 0xfffe\))");
}
if (pac_supported()) {
// Test that the default PAC_ENABLED_KEYS value is set.
ASSERT_MATCH(result, R"(pac_enabled_keys: 000000000000000f)"
R"( \(PR_PAC_APIAKEY, PR_PAC_APIBKEY, PR_PAC_APDAKEY, PR_PAC_APDBKEY\))");
}
}
TEST_F(CrasherTest, tagged_fault_addr) {
#if !defined(__aarch64__)
GTEST_SKIP() << "Requires aarch64";
#endif
// HWASan crashes with SIGABRT on tag mismatch.
SKIP_WITH_HWASAN;
int intercept_result;
unique_fd output_fd;
StartProcess([]() {
*reinterpret_cast<volatile char*>(0x100000000000dead) = '1';
});
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGSEGV);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
// The address can either be tagged (new kernels) or untagged (old kernels).
ASSERT_MATCH(
result, R"(signal 11 \(SIGSEGV\), code 1 \(SEGV_MAPERR\), fault addr 0x[01]00000000000dead)");
}
void CrasherTest::Trap(void* ptr) {
void (*volatile f)(void*) = nullptr;
__asm__ __volatile__("" : : "r"(f) : "memory");
f(ptr);
}
TEST_F(CrasherTest, heap_addr_in_register) {
#if defined(__i386__)
GTEST_SKIP() << "architecture does not pass arguments in registers";
#endif
// The memory dump in HWASan crashes sadly shows the memory near the registers
// in the HWASan dump function, rather the faulting context. This is a known
// issue.
SKIP_WITH_HWASAN;
int intercept_result;
unique_fd output_fd;
StartProcess([]() {
// Crash with a heap pointer in the first argument register.
Trap(malloc(1));
});
StartIntercept(&output_fd);
FinishCrasher();
int status;
ASSERT_EQ(crasher_pid, TIMEOUT(30, waitpid(crasher_pid, &status, 0)));
ASSERT_TRUE(WIFSIGNALED(status)) << "crasher didn't terminate via a signal";
// Don't test the signal number because different architectures use different signals for
// __builtin_trap().
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
#if defined(__aarch64__)
ASSERT_MATCH(result, "memory near x0 \\(\\[anon:");
#elif defined(__arm__)
ASSERT_MATCH(result, "memory near r0 \\(\\[anon:");
#elif defined(__riscv)
ASSERT_MATCH(result, "memory near a0 \\(\\[anon:");
#elif defined(__x86_64__)
ASSERT_MATCH(result, "memory near rdi \\(\\[anon:");
#else
ASSERT_TRUE(false) << "unsupported architecture";
#endif
}
#if defined(__aarch64__)
static void SetTagCheckingLevelSync() {
if (mallopt(M_BIONIC_SET_HEAP_TAGGING_LEVEL, M_HEAP_TAGGING_LEVEL_SYNC) == 0) {
abort();
}
}
static void SetTagCheckingLevelAsync() {
if (mallopt(M_BIONIC_SET_HEAP_TAGGING_LEVEL, M_HEAP_TAGGING_LEVEL_ASYNC) == 0) {
abort();
}
}
#endif
struct SizeParamCrasherTest : CrasherTest, testing::WithParamInterface<size_t> {};
INSTANTIATE_TEST_SUITE_P(Sizes, SizeParamCrasherTest, testing::Values(0, 16, 131072));
TEST_P(SizeParamCrasherTest, mte_uaf) {
#if defined(__aarch64__)
if (!mte_supported()) {
GTEST_SKIP() << "Requires MTE";
}
// Any UAF on a zero-sized allocation will be out-of-bounds so it won't be reported.
if (GetParam() == 0) {
return;
}
LogcatCollector logcat_collector;
int intercept_result;
unique_fd output_fd;
StartProcess([&]() {
SetTagCheckingLevelSync();
volatile int* p = (volatile int*)malloc(GetParam());
free((void *)p);
p[0] = 42;
});
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGSEGV);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::vector<std::string> log_sources(2);
ConsumeFd(std::move(output_fd), &log_sources[0]);
logcat_collector.Collect(&log_sources[1]);
// Tag dump only available in the tombstone, not logcat.
ASSERT_MATCH(log_sources[0], "Memory tags around the fault address");
for (const auto& result : log_sources) {
ASSERT_MATCH(result, R"(signal 11 \(SIGSEGV\))");
ASSERT_MATCH(result, R"(Cause: \[MTE\]: Use After Free, 0 bytes into a )" +
std::to_string(GetParam()) + R"(-byte allocation)");
ASSERT_MATCH(result, R"(deallocated by thread .*?\n.*#00 pc)");
ASSERT_MATCH(result, R"((^|\s)allocated by thread .*?\n.*#00 pc)");
}
#else
GTEST_SKIP() << "Requires aarch64";
#endif
}
TEST_P(SizeParamCrasherTest, mte_oob_uaf) {
#if defined(__aarch64__)
if (!mte_supported()) {
GTEST_SKIP() << "Requires MTE";
}
int intercept_result;
unique_fd output_fd;
StartProcess([&]() {
SetTagCheckingLevelSync();
volatile int* p = (volatile int*)malloc(GetParam());
free((void *)p);
p[-1] = 42;
});
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGSEGV);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_MATCH(result, R"(signal 11 \(SIGSEGV\))");
ASSERT_NOT_MATCH(result, R"(Cause: \[MTE\]: Use After Free, 4 bytes left)");
#else
GTEST_SKIP() << "Requires aarch64";
#endif
}
TEST_P(SizeParamCrasherTest, mte_overflow) {
#if defined(__aarch64__)
if (!mte_supported()) {
GTEST_SKIP() << "Requires MTE";
}
LogcatCollector logcat_collector;
int intercept_result;
unique_fd output_fd;
StartProcess([&]() {
SetTagCheckingLevelSync();
volatile char* p = (volatile char*)malloc(GetParam());
p[GetParam()] = 42;
});
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGSEGV);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::vector<std::string> log_sources(2);
ConsumeFd(std::move(output_fd), &log_sources[0]);
logcat_collector.Collect(&log_sources[1]);
// Tag dump only in tombstone, not logcat, and tagging is not used for
// overflow protection in the scudo secondary (guard pages are used instead).
if (GetParam() < 0x10000) {
ASSERT_MATCH(log_sources[0], "Memory tags around the fault address");
}
for (const auto& result : log_sources) {
ASSERT_MATCH(result, R"(signal 11 \(SIGSEGV\))");
ASSERT_MATCH(result, R"(Cause: \[MTE\]: Buffer Overflow, 0 bytes right of a )" +
std::to_string(GetParam()) + R"(-byte allocation)");
ASSERT_MATCH(result, R"((^|\s)allocated by thread .*?\n.*#00 pc)");
}
#else
GTEST_SKIP() << "Requires aarch64";
#endif
}
TEST_P(SizeParamCrasherTest, mte_underflow) {
#if defined(__aarch64__)
if (!mte_supported()) {
GTEST_SKIP() << "Requires MTE";
}
int intercept_result;
unique_fd output_fd;
StartProcess([&]() {
SetTagCheckingLevelSync();
volatile int* p = (volatile int*)malloc(GetParam());
p[-1] = 42;
});
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGSEGV);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_MATCH(result, R"(signal 11 \(SIGSEGV\), code 9 \(SEGV_MTESERR\))");
ASSERT_MATCH(result, R"(Cause: \[MTE\]: Buffer Underflow, 4 bytes left of a )" +
std::to_string(GetParam()) + R"(-byte allocation)");
ASSERT_MATCH(result, R"((^|\s)allocated by thread .*
#00 pc)");
ASSERT_MATCH(result, "Memory tags around the fault address");
#else
GTEST_SKIP() << "Requires aarch64";
#endif
}
TEST_F(CrasherTest, mte_async) {
#if defined(__aarch64__)
if (!mte_supported()) {
GTEST_SKIP() << "Requires MTE";
}
int intercept_result;
unique_fd output_fd;
StartProcess([&]() {
SetTagCheckingLevelAsync();
volatile int* p = (volatile int*)malloc(16);
p[-1] = 42;
});
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGSEGV);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_MATCH(result, R"(signal 11 \(SIGSEGV\), code [89] \(SEGV_MTE[AS]ERR\), fault addr)");
#else
GTEST_SKIP() << "Requires aarch64";
#endif
}
TEST_F(CrasherTest, mte_multiple_causes) {
#if defined(__aarch64__)
if (!mte_supported()) {
GTEST_SKIP() << "Requires MTE";
}
LogcatCollector logcat_collector;
int intercept_result;
unique_fd output_fd;
StartProcess([]() {
SetTagCheckingLevelSync();
// Make two allocations with the same tag and close to one another. Check for both properties
// with a bounds check -- this relies on the fact that only if the allocations have the same tag
// would they be measured as closer than 128 bytes to each other. Otherwise they would be about
// (some non-zero value << 56) apart.
//
// The out-of-bounds access will be considered either an overflow of one or an underflow of the
// other.
std::set<uintptr_t> allocs;
for (int i = 0; i != 4096; ++i) {
uintptr_t alloc = reinterpret_cast<uintptr_t>(malloc(16));
auto it = allocs.insert(alloc).first;
if (it != allocs.begin() && *std::prev(it) + 128 > alloc) {
*reinterpret_cast<int*>(*std::prev(it) + 16) = 42;
}
if (std::next(it) != allocs.end() && alloc + 128 > *std::next(it)) {
*reinterpret_cast<int*>(alloc + 16) = 42;
}
}
});
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGSEGV);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::vector<std::string> log_sources(2);
ConsumeFd(std::move(output_fd), &log_sources[0]);
logcat_collector.Collect(&log_sources[1]);
// Tag dump only in the tombstone, not logcat.
ASSERT_MATCH(log_sources[0], "Memory tags around the fault address");
for (const auto& result : log_sources) {
ASSERT_MATCH(result, R"(signal 11 \(SIGSEGV\))");
ASSERT_THAT(result, HasSubstr("Note: multiple potential causes for this crash were detected, "
"listing them in decreasing order of likelihood."));
// Adjacent untracked allocations may cause us to see the wrong underflow here (or only
// overflows), so we can't match explicitly for an underflow message.
ASSERT_MATCH(result,
R"(Cause: \[MTE\]: Buffer Overflow, 0 bytes right of a 16-byte allocation)");
// Ensure there's at least two allocation traces (one for each cause).
ASSERT_MATCH(
result,
R"((^|\s)allocated by thread .*?\n.*#00 pc(.|\n)*?(^|\s)allocated by thread .*?\n.*#00 pc)");
}
#else
GTEST_SKIP() << "Requires aarch64";
#endif
}
#if defined(__aarch64__)
static uintptr_t CreateTagMapping() {
// Some of the MTE tag dump tests assert that there is an inaccessible page to the left and right
// of the PROT_MTE page, so map three pages and set the two guard pages to PROT_NONE.
size_t page_size = getpagesize();
void* mapping = mmap(nullptr, page_size * 3, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
uintptr_t mapping_uptr = reinterpret_cast<uintptr_t>(mapping);
if (mapping == MAP_FAILED) {
return 0;
}
mprotect(reinterpret_cast<void*>(mapping_uptr + page_size), page_size,
PROT_READ | PROT_WRITE | PROT_MTE);
// Stripe the mapping, where even granules get tag '1', and odd granules get tag '0'.
for (uintptr_t offset = 0; offset < page_size; offset += 2 * kTagGranuleSize) {
uintptr_t tagged_addr = mapping_uptr + page_size + offset + (1ULL << 56);
__asm__ __volatile__(".arch_extension mte; stg %0, [%0]" : : "r"(tagged_addr) : "memory");
}
return mapping_uptr + page_size;
}
#endif
TEST_F(CrasherTest, mte_register_tag_dump) {
#if defined(__aarch64__)
if (!mte_supported()) {
GTEST_SKIP() << "Requires MTE";
}
int intercept_result;
unique_fd output_fd;
StartProcess([&]() {
SetTagCheckingLevelSync();
Trap(reinterpret_cast<void *>(CreateTagMapping()));
});
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGSEGV);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_MATCH(result, R"(memory near x0:
.*
.*
01.............0 0000000000000000 0000000000000000 ................
00.............0)");
#else
GTEST_SKIP() << "Requires aarch64";
#endif
}
TEST_F(CrasherTest, mte_fault_tag_dump_front_truncated) {
#if defined(__aarch64__)
if (!mte_supported()) {
GTEST_SKIP() << "Requires MTE";
}
int intercept_result;
unique_fd output_fd;
StartProcess([&]() {
SetTagCheckingLevelSync();
volatile char* p = reinterpret_cast<char*>(CreateTagMapping());
p[0] = 0; // Untagged pointer, tagged memory.
});
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGSEGV);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_MATCH(result, R"(Memory tags around the fault address.*
\s*=>0x[0-9a-f]+000:\[1\] 0 1 0)");
#else
GTEST_SKIP() << "Requires aarch64";
#endif
}
TEST_F(CrasherTest, mte_fault_tag_dump) {
#if defined(__aarch64__)
if (!mte_supported()) {
GTEST_SKIP() << "Requires MTE";
}
int intercept_result;
unique_fd output_fd;
StartProcess([&]() {
SetTagCheckingLevelSync();
volatile char* p = reinterpret_cast<char*>(CreateTagMapping());
p[320] = 0; // Untagged pointer, tagged memory.
});
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGSEGV);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_MATCH(result, R"(Memory tags around the fault address.*
\s*0x[0-9a-f]+: 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0
\s*=>0x[0-9a-f]+: 1 0 1 0 \[1\] 0 1 0 1 0 1 0 1 0 1 0
\s*0x[0-9a-f]+: 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0
)");
#else
GTEST_SKIP() << "Requires aarch64";
#endif
}
TEST_F(CrasherTest, mte_fault_tag_dump_rear_truncated) {
#if defined(__aarch64__)
if (!mte_supported()) {
GTEST_SKIP() << "Requires MTE";
}
int intercept_result;
unique_fd output_fd;
StartProcess([&]() {
SetTagCheckingLevelSync();
size_t page_size = getpagesize();
volatile char* p = reinterpret_cast<char*>(CreateTagMapping());
p[page_size - kTagGranuleSize * 2] = 0; // Untagged pointer, tagged memory.
});
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGSEGV);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_MATCH(result, R"(Memory tags around the fault address)");
ASSERT_MATCH(result,
R"(\s*0x[0-9a-f]+: 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0
\s*=>0x[0-9a-f]+: 1 0 1 0 1 0 1 0 1 0 1 0 1 0 \[1\] 0
)"); // Ensure truncation happened and there's a newline after the tag fault.
#else
GTEST_SKIP() << "Requires aarch64";
#endif
}
TEST_F(CrasherTest, LD_PRELOAD) {
int intercept_result;
unique_fd output_fd;
StartProcess([]() {
setenv("LD_PRELOAD", "nonexistent.so", 1);
*reinterpret_cast<volatile char*>(0xdead) = '1';
});
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGSEGV);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_MATCH(result, R"(signal 11 \(SIGSEGV\), code 1 \(SEGV_MAPERR\), fault addr 0x0+dead)");
}
TEST_F(CrasherTest, abort) {
int intercept_result;
unique_fd output_fd;
StartProcess([]() {
abort();
});
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGABRT);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_BACKTRACE_FRAME(result, "abort");
}
TEST_F(CrasherTest, signal) {
int intercept_result;
unique_fd output_fd;
StartProcess([]() {
while (true) {
sleep(1);
}
});
StartIntercept(&output_fd);
FinishCrasher();
ASSERT_EQ(0, kill(crasher_pid, SIGSEGV));
AssertDeath(SIGSEGV);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_MATCH(
result,
R"(signal 11 \(SIGSEGV\), code 0 \(SI_USER from pid \d+, uid \d+\), fault addr --------)");
ASSERT_MATCH(result, R"(backtrace:)");
}
TEST_F(CrasherTest, abort_message) {
int intercept_result;
unique_fd output_fd;
StartProcess([]() {
// Arrived at experimentally;
// logd truncates at 4062.
// strlen("Abort message: ''") is 17.
// That's 4045, but we also want a NUL.
char buf[4045 + 1];
memset(buf, 'x', sizeof(buf));
buf[sizeof(buf) - 1] = '\0';
android_set_abort_message(buf);
abort();
});
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGABRT);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_MATCH(result, R"(Abort message: 'x{4045}')");
}
TEST_F(CrasherTest, abort_message_newline_trimmed) {
int intercept_result;
unique_fd output_fd;
StartProcess([]() {
android_set_abort_message("Message with a newline.\n");
abort();
});
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGABRT);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_MATCH(result, R"(Abort message: 'Message with a newline.')");
}
TEST_F(CrasherTest, abort_message_multiple_newlines_trimmed) {
int intercept_result;
unique_fd output_fd;
StartProcess([]() {
android_set_abort_message("Message with multiple newlines.\n\n\n\n\n");
abort();
});
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGABRT);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_MATCH(result, R"(Abort message: 'Message with multiple newlines.')");
}
TEST_F(CrasherTest, abort_message_backtrace) {
int intercept_result;
unique_fd output_fd;
StartProcess([]() {
android_set_abort_message("not actually aborting");
raise(BIONIC_SIGNAL_DEBUGGER);
exit(0);
});
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(0);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_NOT_MATCH(result, R"(Abort message:)");
}
TEST_F(CrasherTest, intercept_timeout) {
int intercept_result;
unique_fd output_fd;
StartProcess([]() {
abort();
});
StartIntercept(&output_fd);
// Don't let crasher finish until we timeout.
FinishIntercept(&intercept_result);
ASSERT_NE(1, intercept_result) << "tombstoned reported success? (intercept_result = "
<< intercept_result << ")";
FinishCrasher();
AssertDeath(SIGABRT);
}
TEST_F(CrasherTest, wait_for_debugger) {
if (!android::base::SetProperty(kWaitForDebuggerKey, "1")) {
FAIL() << "failed to enable wait_for_debugger";
}
sleep(1);
StartProcess([]() {
abort();
});
FinishCrasher();
int status;
ASSERT_EQ(crasher_pid, TEMP_FAILURE_RETRY(waitpid(crasher_pid, &status, WUNTRACED)));
ASSERT_TRUE(WIFSTOPPED(status));
ASSERT_EQ(SIGSTOP, WSTOPSIG(status));
ASSERT_EQ(0, kill(crasher_pid, SIGCONT));
AssertDeath(SIGABRT);
}
TEST_F(CrasherTest, backtrace) {
std::string result;
int intercept_result;
unique_fd output_fd;
StartProcess([]() {
abort();
});
StartIntercept(&output_fd, kDebuggerdNativeBacktrace);
std::this_thread::sleep_for(500ms);
sigval val;
val.sival_int = 1;
ASSERT_EQ(0, sigqueue(crasher_pid, BIONIC_SIGNAL_DEBUGGER, val)) << strerror(errno);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
ConsumeFd(std::move(output_fd), &result);
ASSERT_BACKTRACE_FRAME(result, "read");
int status;
ASSERT_EQ(0, waitpid(crasher_pid, &status, WNOHANG | WUNTRACED));
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGABRT);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
ConsumeFd(std::move(output_fd), &result);
ASSERT_BACKTRACE_FRAME(result, "abort");
}
TEST_F(CrasherTest, PR_SET_DUMPABLE_0_crash) {
int intercept_result;
unique_fd output_fd;
StartProcess([]() {
prctl(PR_SET_DUMPABLE, 0);
abort();
});
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGABRT);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_BACKTRACE_FRAME(result, "abort");
}
TEST_F(CrasherTest, capabilities) {
ASSERT_EQ(0U, getuid()) << "capability test requires root";
StartProcess([]() {
if (prctl(PR_SET_KEEPCAPS, 1, 0, 0, 0) != 0) {
err(1, "failed to set PR_SET_KEEPCAPS");
}
if (setresuid(1, 1, 1) != 0) {
err(1, "setresuid failed");
}
__user_cap_header_struct capheader;
__user_cap_data_struct capdata[2];
memset(&capheader, 0, sizeof(capheader));
memset(&capdata, 0, sizeof(capdata));
capheader.version = _LINUX_CAPABILITY_VERSION_3;
capheader.pid = 0;
// Turn on every third capability.
static_assert(CAP_LAST_CAP > 33, "CAP_LAST_CAP <= 32");
for (int i = 0; i < CAP_LAST_CAP; i += 3) {
capdata[CAP_TO_INDEX(i)].permitted |= CAP_TO_MASK(i);
capdata[CAP_TO_INDEX(i)].effective |= CAP_TO_MASK(i);
}
// Make sure CAP_SYS_PTRACE is off.
capdata[CAP_TO_INDEX(CAP_SYS_PTRACE)].permitted &= ~(CAP_TO_MASK(CAP_SYS_PTRACE));
capdata[CAP_TO_INDEX(CAP_SYS_PTRACE)].effective &= ~(CAP_TO_MASK(CAP_SYS_PTRACE));
if (capset(&capheader, &capdata[0]) != 0) {
err(1, "capset failed");
}
if (prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_CLEAR_ALL, 0, 0, 0) != 0) {
err(1, "failed to drop ambient capabilities");
}
pthread_setname_np(pthread_self(), "thread_name");
raise(SIGSYS);
});
unique_fd output_fd;
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGSYS);
std::string result;
int intercept_result;
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
ConsumeFd(std::move(output_fd), &result);
ASSERT_MATCH(result, R"(name: thread_name\s+>>> .+debuggerd_test(32|64) <<<)");
ASSERT_BACKTRACE_FRAME(result, "tgkill");
}
TEST_F(CrasherTest, fake_pid) {
int intercept_result;
unique_fd output_fd;
// Prime the getpid/gettid caches.
UNUSED(getpid());
UNUSED(gettid());
std::function<pid_t()> clone_fn = []() {
return syscall(__NR_clone, SIGCHLD, nullptr, nullptr, nullptr, nullptr);
};
StartProcess(
[]() {
ASSERT_NE(getpid(), syscall(__NR_getpid));
ASSERT_NE(gettid(), syscall(__NR_gettid));
raise(SIGSEGV);
},
clone_fn);
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGSEGV);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_BACKTRACE_FRAME(result, "tgkill");
}
static const char* const kDebuggerdSeccompPolicy =
"/system/etc/seccomp_policy/crash_dump." ABI_STRING ".policy";
static void setup_jail(minijail* jail) {
if (!jail) {
LOG(FATAL) << "failed to create minijail";
}
std::string policy;
if (!android::base::ReadFileToString(kDebuggerdSeccompPolicy, &policy)) {
PLOG(FATAL) << "failed to read policy file";
}
// Allow a bunch of syscalls used by the tests.
policy += "\nclone: 1";
policy += "\nsigaltstack: 1";
policy += "\nnanosleep: 1";
policy += "\ngetrlimit: 1";
policy += "\nugetrlimit: 1";
FILE* tmp_file = tmpfile();
if (!tmp_file) {
PLOG(FATAL) << "tmpfile failed";
}
unique_fd tmp_fd(TEMP_FAILURE_RETRY(dup(fileno(tmp_file))));
if (!android::base::WriteStringToFd(policy, tmp_fd.get())) {
PLOG(FATAL) << "failed to write policy to tmpfile";
}
if (lseek(tmp_fd.get(), 0, SEEK_SET) != 0) {
PLOG(FATAL) << "failed to seek tmp_fd";
}
minijail_no_new_privs(jail);
minijail_log_seccomp_filter_failures(jail);
minijail_use_seccomp_filter(jail);
minijail_parse_seccomp_filters_from_fd(jail, tmp_fd.release());
}
static pid_t seccomp_fork_impl(void (*prejail)()) {
ScopedMinijail jail{minijail_new()};
setup_jail(jail.get());
pid_t result = fork();
if (result == -1) {
return result;
} else if (result != 0) {
return result;
}
// Spawn and detach a thread that spins forever.
std::atomic<bool> thread_ready(false);
std::thread thread([&jail, &thread_ready]() {
minijail_enter(jail.get());
thread_ready = true;
for (;;)
;
});
thread.detach();
while (!thread_ready) {
continue;
}
if (prejail) {
prejail();
}
minijail_enter(jail.get());
return result;
}
static pid_t seccomp_fork() {
return seccomp_fork_impl(nullptr);
}
TEST_F(CrasherTest, seccomp_crash) {
int intercept_result;
unique_fd output_fd;
StartProcess([]() { abort(); }, &seccomp_fork);
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGABRT);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_BACKTRACE_FRAME(result, "abort");
}
static pid_t seccomp_fork_rlimit() {
return seccomp_fork_impl([]() {
struct rlimit rlim = {
.rlim_cur = 512 * 1024 * 1024,
.rlim_max = 512 * 1024 * 1024,
};
if (setrlimit(RLIMIT_AS, &rlim) != 0) {
raise(SIGINT);
}
});
}
TEST_F(CrasherTest, seccomp_crash_oom) {
int intercept_result;
unique_fd output_fd;
StartProcess(
[]() {
std::vector<void*> vec;
for (int i = 0; i < 512; ++i) {
char* buf = static_cast<char*>(malloc(1024 * 1024));
if (!buf) {
abort();
}
memset(buf, 0xff, 1024 * 1024);
vec.push_back(buf);
}
},
&seccomp_fork_rlimit);
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGABRT);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
// We can't actually generate a backtrace, just make sure that the process terminates.
}
__attribute__((__noinline__)) extern "C" bool raise_debugger_signal(DebuggerdDumpType dump_type) {
siginfo_t siginfo;
siginfo.si_code = SI_QUEUE;
siginfo.si_pid = getpid();
siginfo.si_uid = getuid();
if (dump_type != kDebuggerdNativeBacktrace && dump_type != kDebuggerdTombstone) {
PLOG(FATAL) << "invalid dump type";
}
siginfo.si_value.sival_int = dump_type == kDebuggerdNativeBacktrace;
if (syscall(__NR_rt_tgsigqueueinfo, getpid(), gettid(), BIONIC_SIGNAL_DEBUGGER, &siginfo) != 0) {
PLOG(ERROR) << "libdebuggerd_client: failed to send signal to self";
return false;
}
return true;
}
extern "C" void foo() {
LOG(INFO) << "foo";
std::this_thread::sleep_for(1s);
}
extern "C" void bar() {
LOG(INFO) << "bar";
std::this_thread::sleep_for(1s);
}
TEST_F(CrasherTest, seccomp_tombstone) {
int intercept_result;
unique_fd output_fd;
static const auto dump_type = kDebuggerdTombstone;
StartProcess(
[]() {
std::thread a(foo);
std::thread b(bar);
std::this_thread::sleep_for(100ms);
raise_debugger_signal(dump_type);
_exit(0);
},
&seccomp_fork);
StartIntercept(&output_fd, dump_type);
FinishCrasher();
AssertDeath(0);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_BACKTRACE_FRAME(result, "raise_debugger_signal");
ASSERT_BACKTRACE_FRAME(result, "foo");
ASSERT_BACKTRACE_FRAME(result, "bar");
}
TEST_F(CrasherTest, seccomp_tombstone_thread_abort) {
int intercept_result;
unique_fd output_fd;
static const auto dump_type = kDebuggerdTombstone;
StartProcess(
[]() {
std::thread abort_thread([] { abort(); });
abort_thread.join();
},
&seccomp_fork);
StartIntercept(&output_fd, dump_type);
FinishCrasher();
AssertDeath(SIGABRT);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_BACKTRACE_FRAME(result, "abort");
}
TEST_F(CrasherTest, seccomp_tombstone_multiple_threads_abort) {
int intercept_result;
unique_fd output_fd;
static const auto dump_type = kDebuggerdTombstone;
StartProcess(
[]() {
std::thread a(foo);
std::thread b(bar);
std::this_thread::sleep_for(100ms);
std::thread abort_thread([] { abort(); });
abort_thread.join();
},
&seccomp_fork);
StartIntercept(&output_fd, dump_type);
FinishCrasher();
AssertDeath(SIGABRT);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_BACKTRACE_FRAME(result, "abort");
ASSERT_BACKTRACE_FRAME(result, "foo");
ASSERT_BACKTRACE_FRAME(result, "bar");
ASSERT_BACKTRACE_FRAME(result, "main");
}
TEST_F(CrasherTest, seccomp_backtrace) {
int intercept_result;
unique_fd output_fd;
static const auto dump_type = kDebuggerdNativeBacktrace;
StartProcess(
[]() {
std::thread a(foo);
std::thread b(bar);
std::this_thread::sleep_for(100ms);
raise_debugger_signal(dump_type);
_exit(0);
},
&seccomp_fork);
StartIntercept(&output_fd, dump_type);
FinishCrasher();
AssertDeath(0);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_BACKTRACE_FRAME(result, "raise_debugger_signal");
ASSERT_BACKTRACE_FRAME(result, "foo");
ASSERT_BACKTRACE_FRAME(result, "bar");
}
TEST_F(CrasherTest, seccomp_backtrace_from_thread) {
int intercept_result;
unique_fd output_fd;
static const auto dump_type = kDebuggerdNativeBacktrace;
StartProcess(
[]() {
std::thread a(foo);
std::thread b(bar);
std::this_thread::sleep_for(100ms);
std::thread raise_thread([] {
raise_debugger_signal(dump_type);
_exit(0);
});
raise_thread.join();
},
&seccomp_fork);
StartIntercept(&output_fd, dump_type);
FinishCrasher();
AssertDeath(0);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_BACKTRACE_FRAME(result, "raise_debugger_signal");
ASSERT_BACKTRACE_FRAME(result, "foo");
ASSERT_BACKTRACE_FRAME(result, "bar");
ASSERT_BACKTRACE_FRAME(result, "main");
}
TEST_F(CrasherTest, seccomp_crash_logcat) {
StartProcess([]() { abort(); }, &seccomp_fork);
FinishCrasher();
// Make sure we don't get SIGSYS when trying to dump a crash to logcat.
AssertDeath(SIGABRT);
}
TEST_F(CrasherTest, competing_tracer) {
int intercept_result;
unique_fd output_fd;
StartProcess([]() {
raise(SIGABRT);
});
StartIntercept(&output_fd);
ASSERT_EQ(0, ptrace(PTRACE_SEIZE, crasher_pid, 0, 0));
FinishCrasher();
int status;
ASSERT_EQ(crasher_pid, TEMP_FAILURE_RETRY(waitpid(crasher_pid, &status, 0)));
ASSERT_TRUE(WIFSTOPPED(status));
ASSERT_EQ(SIGABRT, WSTOPSIG(status));
ASSERT_EQ(0, ptrace(PTRACE_CONT, crasher_pid, 0, SIGABRT));
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
std::string regex = R"(failed to attach to thread \d+, already traced by )";
regex += std::to_string(gettid());
regex += R"( \(.+debuggerd_test)";
ASSERT_MATCH(result, regex.c_str());
ASSERT_EQ(crasher_pid, TEMP_FAILURE_RETRY(waitpid(crasher_pid, &status, 0)));
ASSERT_TRUE(WIFSTOPPED(status));
ASSERT_EQ(SIGABRT, WSTOPSIG(status));
ASSERT_EQ(0, ptrace(PTRACE_DETACH, crasher_pid, 0, SIGABRT));
AssertDeath(SIGABRT);
}
struct GwpAsanTestParameters {
size_t alloc_size;
bool free_before_access;
int access_offset;
std::string cause_needle; // Needle to be found in the "Cause: [GWP-ASan]" line.
};
struct GwpAsanCrasherTest
: CrasherTest,
testing::WithParamInterface<
std::tuple<GwpAsanTestParameters, /* recoverable */ bool, /* seccomp */ bool>> {};
GwpAsanTestParameters gwp_asan_tests[] = {
{/* alloc_size */ 7, /* free_before_access */ true, /* access_offset */ 0,
"Use After Free, 0 bytes into a 7-byte allocation"},
{/* alloc_size */ 15, /* free_before_access */ true, /* access_offset */ 1,
"Use After Free, 1 byte into a 15-byte allocation"},
{/* alloc_size */ 4096, /* free_before_access */ false, /* access_offset */ 4098,
"Buffer Overflow, 2 bytes right of a 4096-byte allocation"},
{/* alloc_size */ 4096, /* free_before_access */ false, /* access_offset */ -1,
"Buffer Underflow, 1 byte left of a 4096-byte allocation"},
};
INSTANTIATE_TEST_SUITE_P(
GwpAsanTests, GwpAsanCrasherTest,
testing::Combine(testing::ValuesIn(gwp_asan_tests),
/* recoverable */ testing::Bool(),
/* seccomp */ testing::Bool()),
[](const testing::TestParamInfo<
std::tuple<GwpAsanTestParameters, /* recoverable */ bool, /* seccomp */ bool>>& info) {
const GwpAsanTestParameters& params = std::get<0>(info.param);
std::string name = params.free_before_access ? "UseAfterFree" : "Overflow";
name += testing::PrintToString(params.alloc_size);
name += "Alloc";
if (params.access_offset < 0) {
name += "Left";
name += testing::PrintToString(params.access_offset * -1);
} else {
name += "Right";
name += testing::PrintToString(params.access_offset);
}
name += "Bytes";
if (std::get<1>(info.param)) name += "Recoverable";
if (std::get<2>(info.param)) name += "Seccomp";
return name;
});
TEST_P(GwpAsanCrasherTest, run_gwp_asan_test) {
if (mte_supported()) {
// Skip this test on MTE hardware, as MTE will reliably catch these errors
// instead of GWP-ASan.
GTEST_SKIP() << "Skipped on MTE.";
}
// Skip this test on HWASan, which will reliably catch test errors as well.
SKIP_WITH_HWASAN;
GwpAsanTestParameters params = std::get<0>(GetParam());
bool recoverable = std::get<1>(GetParam());
LogcatCollector logcat_collector;
int intercept_result;
unique_fd output_fd;
StartProcess([&recoverable]() {
const char* env[] = {"GWP_ASAN_SAMPLE_RATE=1", "GWP_ASAN_PROCESS_SAMPLING=1",
"GWP_ASAN_MAX_ALLOCS=40000", nullptr, nullptr};
if (recoverable) {
env[3] = "GWP_ASAN_RECOVERABLE=true";
}
std::string test_name = ::testing::UnitTest::GetInstance()->current_test_info()->name();
test_name = std::regex_replace(test_name, std::regex("run_gwp_asan_test"),
"DISABLED_run_gwp_asan_test");
std::string test_filter = "--gtest_filter=*";
test_filter += test_name;
std::string this_binary = android::base::GetExecutablePath();
const char* args[] = {this_binary.c_str(), "--gtest_also_run_disabled_tests",
test_filter.c_str(), nullptr};
// We check the crash report from a debuggerd handler and from logcat. The
// echo from stdout/stderr of the subprocess trips up atest, because it
// doesn't like that two tests started in a row without the first one
// finishing (even though the second one is in a subprocess).
close(STDOUT_FILENO);
close(STDERR_FILENO);
execve(this_binary.c_str(), const_cast<char**>(args), const_cast<char**>(env));
});
StartIntercept(&output_fd);
FinishCrasher();
if (recoverable) {
AssertDeath(0);
} else {
AssertDeath(SIGSEGV);
}
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::vector<std::string> log_sources(2);
ConsumeFd(std::move(output_fd), &log_sources[0]);
logcat_collector.Collect(&log_sources[1]);
// seccomp forces the fallback handler, which doesn't print GWP-ASan debugging
// information. Make sure the recovery still works, but the report won't be
// hugely useful, it looks like a regular SEGV.
bool seccomp = std::get<2>(GetParam());
if (!seccomp) {
for (const auto& result : log_sources) {
ASSERT_MATCH(result, R"(signal 11 \(SIGSEGV\), code 2 \(SEGV_ACCERR\))");
ASSERT_MATCH(result, R"(Cause: \[GWP-ASan\]: )" + params.cause_needle);
if (params.free_before_access) {
ASSERT_MATCH(result, R"(deallocated by thread .*\n.*#00 pc)");
}
ASSERT_MATCH(result, R"((^|\s)allocated by thread .*\n.*#00 pc)");
}
}
}
TEST_P(GwpAsanCrasherTest, DISABLED_run_gwp_asan_test) {
GwpAsanTestParameters params = std::get<0>(GetParam());
bool seccomp = std::get<2>(GetParam());
if (seccomp) {
ScopedMinijail jail{minijail_new()};
setup_jail(jail.get());
minijail_enter(jail.get());
}
// Use 'volatile' to prevent a very clever compiler eliminating the store.
char* volatile p = reinterpret_cast<char* volatile>(malloc(params.alloc_size));
if (params.free_before_access) free(static_cast<void*>(const_cast<char*>(p)));
p[params.access_offset] = 42;
if (!params.free_before_access) free(static_cast<void*>(const_cast<char*>(p)));
bool recoverable = std::get<1>(GetParam());
ASSERT_TRUE(recoverable); // Non-recoverable should have crashed.
// As we're in recoverable mode, trigger another 2x use-after-frees (ensuring
// we end with at least one in a different slot), make sure the process still
// doesn't crash.
p = reinterpret_cast<char* volatile>(malloc(params.alloc_size));
char* volatile p2 = reinterpret_cast<char* volatile>(malloc(params.alloc_size));
free(static_cast<void*>(const_cast<char*>(p)));
free(static_cast<void*>(const_cast<char*>(p2)));
*p = 42;
*p2 = 42;
// Under clang coverage (which is a default TEST_MAPPING presubmit target), the
// recoverable+seccomp tests fail because the minijail prevents some atexit syscalls that clang
// coverage does. Thus, skip the atexit handlers.
_exit(0);
}
TEST_F(CrasherTest, fdsan_warning_abort_message) {
int intercept_result;
unique_fd output_fd;
StartProcess([]() {
android_fdsan_set_error_level(ANDROID_FDSAN_ERROR_LEVEL_WARN_ONCE);
unique_fd fd(TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY | O_CLOEXEC)));
if (fd == -1) {
abort();
}
close(fd.get());
_exit(0);
});
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(0);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_MATCH(result, "Abort message: 'attempted to close");
}
TEST(crash_dump, zombie) {
pid_t forkpid = fork();
pid_t rc;
int status;
if (forkpid == 0) {
errno = 0;
rc = waitpid(-1, &status, WNOHANG | __WALL | __WNOTHREAD);
if (rc != -1 || errno != ECHILD) {
errx(2, "first waitpid returned %d (%s), expected failure with ECHILD", rc, strerror(errno));
}
raise(BIONIC_SIGNAL_DEBUGGER);
errno = 0;
rc = TEMP_FAILURE_RETRY(waitpid(-1, &status, __WALL | __WNOTHREAD));
if (rc != -1 || errno != ECHILD) {
errx(2, "second waitpid returned %d (%s), expected failure with ECHILD", rc, strerror(errno));
}
_exit(0);
} else {
rc = TEMP_FAILURE_RETRY(waitpid(forkpid, &status, 0));
ASSERT_EQ(forkpid, rc);
ASSERT_TRUE(WIFEXITED(status));
ASSERT_EQ(0, WEXITSTATUS(status));
}
}
TEST(tombstoned, no_notify) {
// Do this a few times.
for (int i = 0; i < 3; ++i) {
pid_t pid = 123'456'789 + i;
unique_fd intercept_fd, output_fd;
InterceptStatus status;
tombstoned_intercept(pid, &intercept_fd, &output_fd, &status, kDebuggerdTombstone);
ASSERT_EQ(InterceptStatus::kRegistered, status);
{
unique_fd tombstoned_socket, input_fd;
ASSERT_TRUE(tombstoned_connect(pid, &tombstoned_socket, &input_fd, kDebuggerdTombstone));
ASSERT_TRUE(android::base::WriteFully(input_fd.get(), &pid, sizeof(pid)));
}
pid_t read_pid;
ASSERT_TRUE(android::base::ReadFully(output_fd.get(), &read_pid, sizeof(read_pid)));
ASSERT_EQ(read_pid, pid);
}
}
TEST(tombstoned, stress) {
// Spawn threads to simultaneously do a bunch of failing dumps and a bunch of successful dumps.
static constexpr int kDumpCount = 100;
std::atomic<bool> start(false);
std::vector<std::thread> threads;
threads.emplace_back([&start]() {
while (!start) {
continue;
}
// Use a way out of range pid, to avoid stomping on an actual process.
pid_t pid_base = 1'000'000;
for (int dump = 0; dump < kDumpCount; ++dump) {
pid_t pid = pid_base + dump;
unique_fd intercept_fd, output_fd;
InterceptStatus status;
tombstoned_intercept(pid, &intercept_fd, &output_fd, &status, kDebuggerdTombstone);
ASSERT_EQ(InterceptStatus::kRegistered, status);
// Pretend to crash, and then immediately close the socket.
unique_fd sockfd(socket_local_client(kTombstonedCrashSocketName,
ANDROID_SOCKET_NAMESPACE_RESERVED, SOCK_SEQPACKET));
if (sockfd == -1) {
FAIL() << "failed to connect to tombstoned: " << strerror(errno);
}
TombstonedCrashPacket packet = {};
packet.packet_type = CrashPacketType::kDumpRequest;
packet.packet.dump_request.pid = pid;
if (TEMP_FAILURE_RETRY(write(sockfd, &packet, sizeof(packet))) != sizeof(packet)) {
FAIL() << "failed to write to tombstoned: " << strerror(errno);
}
continue;
}
});
threads.emplace_back([&start]() {
while (!start) {
continue;
}
// Use a way out of range pid, to avoid stomping on an actual process.
pid_t pid_base = 2'000'000;
for (int dump = 0; dump < kDumpCount; ++dump) {
pid_t pid = pid_base + dump;
unique_fd intercept_fd, output_fd;
InterceptStatus status;
tombstoned_intercept(pid, &intercept_fd, &output_fd, &status, kDebuggerdTombstone);
ASSERT_EQ(InterceptStatus::kRegistered, status);
{
unique_fd tombstoned_socket, input_fd;
ASSERT_TRUE(tombstoned_connect(pid, &tombstoned_socket, &input_fd, kDebuggerdTombstone));
ASSERT_TRUE(android::base::WriteFully(input_fd.get(), &pid, sizeof(pid)));
tombstoned_notify_completion(tombstoned_socket.get());
}
// TODO: Fix the race that requires this sleep.
std::this_thread::sleep_for(50ms);
pid_t read_pid;
ASSERT_TRUE(android::base::ReadFully(output_fd.get(), &read_pid, sizeof(read_pid)));
ASSERT_EQ(read_pid, pid);
}
});
start = true;
for (std::thread& thread : threads) {
thread.join();
}
}
TEST(tombstoned, java_trace_intercept_smoke) {
// Using a "real" PID is a little dangerous here - if the test fails
// or crashes, we might end up getting a bogus / unreliable stack
// trace.
const pid_t self = getpid();
unique_fd intercept_fd, output_fd;
InterceptStatus status;
tombstoned_intercept(self, &intercept_fd, &output_fd, &status, kDebuggerdJavaBacktrace);
ASSERT_EQ(InterceptStatus::kRegistered, status);
// First connect to tombstoned requesting a native tombstone. This
// should result in a "regular" FD and not the installed intercept.
const char native[] = "native";
unique_fd tombstoned_socket, input_fd;
ASSERT_TRUE(tombstoned_connect(self, &tombstoned_socket, &input_fd, kDebuggerdTombstone));
ASSERT_TRUE(android::base::WriteFully(input_fd.get(), native, sizeof(native)));
tombstoned_notify_completion(tombstoned_socket.get());
// Then, connect to tombstoned asking for a java backtrace. This *should*
// trigger the intercept.
const char java[] = "java";
ASSERT_TRUE(tombstoned_connect(self, &tombstoned_socket, &input_fd, kDebuggerdJavaBacktrace));
ASSERT_TRUE(android::base::WriteFully(input_fd.get(), java, sizeof(java)));
tombstoned_notify_completion(tombstoned_socket.get());
char outbuf[sizeof(java)];
ASSERT_TRUE(android::base::ReadFully(output_fd.get(), outbuf, sizeof(outbuf)));
ASSERT_STREQ("java", outbuf);
}
TEST(tombstoned, multiple_intercepts) {
const pid_t fake_pid = 1'234'567;
unique_fd intercept_fd, output_fd;
InterceptStatus status;
tombstoned_intercept(fake_pid, &intercept_fd, &output_fd, &status, kDebuggerdJavaBacktrace);
ASSERT_EQ(InterceptStatus::kRegistered, status);
unique_fd intercept_fd_2, output_fd_2;
tombstoned_intercept(fake_pid, &intercept_fd_2, &output_fd_2, &status, kDebuggerdNativeBacktrace);
ASSERT_EQ(InterceptStatus::kFailedAlreadyRegistered, status);
}
TEST(tombstoned, intercept_any) {
const pid_t fake_pid = 1'234'567;
unique_fd intercept_fd, output_fd;
InterceptStatus status;
tombstoned_intercept(fake_pid, &intercept_fd, &output_fd, &status, kDebuggerdNativeBacktrace);
ASSERT_EQ(InterceptStatus::kRegistered, status);
const char any[] = "any";
unique_fd tombstoned_socket, input_fd;
ASSERT_TRUE(tombstoned_connect(fake_pid, &tombstoned_socket, &input_fd, kDebuggerdAnyIntercept));
ASSERT_TRUE(android::base::WriteFully(input_fd.get(), any, sizeof(any)));
tombstoned_notify_completion(tombstoned_socket.get());
char outbuf[sizeof(any)];
ASSERT_TRUE(android::base::ReadFully(output_fd.get(), outbuf, sizeof(outbuf)));
ASSERT_STREQ("any", outbuf);
}
TEST(tombstoned, interceptless_backtrace) {
// Generate 50 backtraces, and then check to see that we haven't created 50 new tombstones.
auto get_tombstone_timestamps = []() -> std::map<int, time_t> {
std::map<int, time_t> result;
for (int i = 0; i < 99; ++i) {
std::string path = android::base::StringPrintf("/data/tombstones/tombstone_%02d", i);
struct stat st;
if (stat(path.c_str(), &st) == 0) {
result[i] = st.st_mtim.tv_sec;
}
}
return result;
};
auto before = get_tombstone_timestamps();
for (int i = 0; i < 50; ++i) {
raise_debugger_signal(kDebuggerdNativeBacktrace);
}
auto after = get_tombstone_timestamps();
int diff = 0;
for (int i = 0; i < 99; ++i) {
if (after.count(i) == 0) {
continue;
}
if (before.count(i) == 0) {
++diff;
continue;
}
if (before[i] != after[i]) {
++diff;
}
}
// We can't be sure that nothing's crash looping in the background.
// This should be good enough, though...
ASSERT_LT(diff, 10) << "too many new tombstones; is something crashing in the background?";
}
static __attribute__((__noinline__)) void overflow_stack(void* p) {
void* buf[1];
buf[0] = p;
static volatile void* global = buf;
if (global) {
global = buf;
overflow_stack(&buf);
}
}
TEST_F(CrasherTest, stack_overflow) {
int intercept_result;
unique_fd output_fd;
StartProcess([]() { overflow_stack(nullptr); });
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGSEGV);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_MATCH(result, R"(Cause: stack pointer[^\n]*stack overflow.\n)");
}
static std::string GetTestLibraryPath() {
std::string test_lib(testing::internal::GetArgvs()[0]);
auto const value = test_lib.find_last_of('/');
if (value == std::string::npos) {
test_lib = "./";
} else {
test_lib = test_lib.substr(0, value + 1) + "./";
}
return test_lib + "libcrash_test.so";
}
static void CreateEmbeddedLibrary(int out_fd) {
std::string test_lib(GetTestLibraryPath());
android::base::unique_fd fd(open(test_lib.c_str(), O_RDONLY | O_CLOEXEC));
ASSERT_NE(fd.get(), -1);
off_t file_size = lseek(fd, 0, SEEK_END);
ASSERT_EQ(lseek(fd, 0, SEEK_SET), 0);
std::vector<uint8_t> contents(file_size);
ASSERT_TRUE(android::base::ReadFully(fd, contents.data(), contents.size()));
// Put the shared library data at a pagesize() offset.
ASSERT_EQ(lseek(out_fd, 4 * getpagesize(), SEEK_CUR), 4 * getpagesize());
ASSERT_EQ(static_cast<size_t>(write(out_fd, contents.data(), contents.size())), contents.size());
}
TEST_F(CrasherTest, non_zero_offset_in_library) {
int intercept_result;
unique_fd output_fd;
TemporaryFile tf;
CreateEmbeddedLibrary(tf.fd);
StartProcess([&tf]() {
android_dlextinfo extinfo{};
extinfo.flags = ANDROID_DLEXT_USE_LIBRARY_FD | ANDROID_DLEXT_USE_LIBRARY_FD_OFFSET;
extinfo.library_fd = tf.fd;
extinfo.library_fd_offset = 4 * getpagesize();
void* handle = android_dlopen_ext(tf.path, RTLD_NOW, &extinfo);
if (handle == nullptr) {
_exit(1);
}
void (*crash_func)() = reinterpret_cast<void (*)()>(dlsym(handle, "crash"));
if (crash_func == nullptr) {
_exit(1);
}
crash_func();
});
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGSEGV);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
// Verify the crash includes an offset value in the backtrace.
std::string match_str = android::base::StringPrintf("%s\\!libcrash_test.so \\(offset 0x%x\\)",
tf.path, 4 * getpagesize());
ASSERT_MATCH(result, match_str);
}
static bool CopySharedLibrary(const char* tmp_dir, std::string* tmp_so_name) {
std::string test_lib(GetTestLibraryPath());
*tmp_so_name = std::string(tmp_dir) + "/libcrash_test.so";
std::string cp_cmd = android::base::StringPrintf("cp %s %s", test_lib.c_str(), tmp_dir);
// Copy the shared so to a tempory directory.
return system(cp_cmd.c_str()) == 0;
}
TEST_F(CrasherTest, unreadable_elf) {
int intercept_result;
unique_fd output_fd;
std::string tmp_so_name;
StartProcess([&tmp_so_name]() {
TemporaryDir td;
if (!CopySharedLibrary(td.path, &tmp_so_name)) {
_exit(1);
}
void* handle = dlopen(tmp_so_name.c_str(), RTLD_NOW);
if (handle == nullptr) {
_exit(1);
}
// Delete the original shared library so that we get the warning
// about unreadable elf files.
if (unlink(tmp_so_name.c_str()) == -1) {
_exit(1);
}
void (*crash_func)() = reinterpret_cast<void (*)()>(dlsym(handle, "crash"));
if (crash_func == nullptr) {
_exit(1);
}
crash_func();
});
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGSEGV);
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_MATCH(result, R"(NOTE: Function names and BuildId information is missing )");
std::string match_str = "NOTE: " + tmp_so_name;
ASSERT_MATCH(result, match_str);
}
TEST(tombstoned, proto) {
const pid_t self = getpid();
unique_fd tombstoned_socket, text_fd, proto_fd;
ASSERT_TRUE(
tombstoned_connect(self, &tombstoned_socket, &text_fd, &proto_fd, kDebuggerdTombstoneProto));
tombstoned_notify_completion(tombstoned_socket.get());
ASSERT_NE(-1, text_fd.get());
ASSERT_NE(-1, proto_fd.get());
struct stat text_st;
ASSERT_EQ(0, fstat(text_fd.get(), &text_st));
// Give tombstoned some time to link the files into place.
std::this_thread::sleep_for(100ms);
// Find the tombstone.
std::optional<std::string> tombstone_file;
std::unique_ptr<DIR, decltype(&closedir)> dir_h(opendir("/data/tombstones"), closedir);
ASSERT_TRUE(dir_h != nullptr);
std::regex tombstone_re("tombstone_\\d+");
dirent* entry;
while ((entry = readdir(dir_h.get())) != nullptr) {
if (!std::regex_match(entry->d_name, tombstone_re)) {
continue;
}
std::string path = android::base::StringPrintf("/data/tombstones/%s", entry->d_name);
struct stat st;
if (TEMP_FAILURE_RETRY(stat(path.c_str(), &st)) != 0) {
continue;
}
if (st.st_dev == text_st.st_dev && st.st_ino == text_st.st_ino) {
tombstone_file = path;
break;
}
}
ASSERT_TRUE(tombstone_file);
std::string proto_path = tombstone_file.value() + ".pb";
struct stat proto_fd_st;
struct stat proto_file_st;
ASSERT_EQ(0, fstat(proto_fd.get(), &proto_fd_st));
ASSERT_EQ(0, stat(proto_path.c_str(), &proto_file_st));
ASSERT_EQ(proto_fd_st.st_dev, proto_file_st.st_dev);
ASSERT_EQ(proto_fd_st.st_ino, proto_file_st.st_ino);
}
TEST(tombstoned, proto_intercept) {
const pid_t self = getpid();
unique_fd intercept_fd, output_fd;
InterceptStatus status;
tombstoned_intercept(self, &intercept_fd, &output_fd, &status, kDebuggerdTombstone);
ASSERT_EQ(InterceptStatus::kRegistered, status);
unique_fd tombstoned_socket, text_fd, proto_fd;
ASSERT_TRUE(
tombstoned_connect(self, &tombstoned_socket, &text_fd, &proto_fd, kDebuggerdTombstoneProto));
ASSERT_TRUE(android::base::WriteStringToFd("foo", text_fd.get()));
tombstoned_notify_completion(tombstoned_socket.get());
text_fd.reset();
std::string output;
ASSERT_TRUE(android::base::ReadFdToString(output_fd, &output));
ASSERT_EQ("foo", output);
}
// Verify that when an intercept is present for the main thread, and the signal
// is received on a different thread, the intercept still works.
TEST_F(CrasherTest, intercept_for_main_thread_signal_on_side_thread) {
StartProcess([]() {
std::thread thread([]() {
// Raise the signal on the side thread.
raise_debugger_signal(kDebuggerdNativeBacktrace);
});
thread.join();
_exit(0);
});
unique_fd output_fd;
StartIntercept(&output_fd, kDebuggerdNativeBacktrace);
FinishCrasher();
AssertDeath(0);
int intercept_result;
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_BACKTRACE_FRAME(result, "raise_debugger_signal");
}
static std::string format_pointer(uintptr_t ptr) {
#if defined(__LP64__)
return android::base::StringPrintf("%08x'%08x", static_cast<uint32_t>(ptr >> 32),
static_cast<uint32_t>(ptr & 0xffffffff));
#else
return android::base::StringPrintf("%08x", static_cast<uint32_t>(ptr & 0xffffffff));
#endif
}
static std::string format_pointer(void* ptr) {
return format_pointer(reinterpret_cast<uintptr_t>(ptr));
}
static std::string format_full_pointer(uintptr_t ptr) {
#if defined(__LP64__)
return android::base::StringPrintf("%016" PRIx64, ptr);
#else
return android::base::StringPrintf("%08x", ptr);
#endif
}
static std::string format_full_pointer(void* ptr) {
return format_full_pointer(reinterpret_cast<uintptr_t>(ptr));
}
__attribute__((__noinline__)) int crash_call(uintptr_t ptr) {
int* crash_ptr = reinterpret_cast<int*>(ptr);
*crash_ptr = 1;
return *crash_ptr;
}
// Verify that a fault address before the first map is properly handled.
TEST_F(CrasherTest, fault_address_before_first_map) {
StartProcess([]() {
ASSERT_EQ(0, crash_call(0x1024));
_exit(0);
});
unique_fd output_fd;
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGSEGV);
int intercept_result;
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_MATCH(result, R"(signal 11 \(SIGSEGV\), code 1 \(SEGV_MAPERR\), fault addr 0x0+1024)");
ASSERT_MATCH(result, R"(\nmemory map \(.*\):\n)");
std::string match_str = android::base::StringPrintf(
R"(memory map .*:\n--->Fault address falls at %s before any mapped regions\n )",
format_pointer(0x1024).c_str());
ASSERT_MATCH(result, match_str);
}
// Verify that a fault address after the last map is properly handled.
TEST_F(CrasherTest, fault_address_after_last_map) {
// This makes assumptions about the memory layout that are not true in HWASan
// processes.
SKIP_WITH_HWASAN;
uintptr_t crash_uptr = untag_address(UINTPTR_MAX - 15);
StartProcess([crash_uptr]() {
ASSERT_EQ(0, crash_call(crash_uptr));
_exit(0);
});
unique_fd output_fd;
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGSEGV);
int intercept_result;
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
std::string match_str = R"(signal 11 \(SIGSEGV\), code 1 \(SEGV_MAPERR\), fault addr 0x)";
match_str += format_full_pointer(crash_uptr);
ASSERT_MATCH(result, match_str);
ASSERT_MATCH(result, R"(\nmemory map \(.*\): \(fault address prefixed with --->)\n)");
// Assumes that the open files section comes after the map section.
// If that assumption changes, the regex below needs to change.
match_str = android::base::StringPrintf(
R"(\n--->Fault address falls at %s after any mapped regions\n\nopen files:)",
format_pointer(crash_uptr).c_str());
ASSERT_MATCH(result, match_str);
}
// Verify that a fault address between maps is properly handled.
TEST_F(CrasherTest, fault_address_between_maps) {
// Create a map before the fork so it will be present in the child.
void* start_ptr =
mmap(nullptr, 3 * getpagesize(), PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
ASSERT_NE(MAP_FAILED, start_ptr);
// Unmap the page in the middle.
void* middle_ptr =
reinterpret_cast<void*>(reinterpret_cast<uintptr_t>(start_ptr) + getpagesize());
ASSERT_EQ(0, munmap(middle_ptr, getpagesize()));
StartProcess([middle_ptr]() {
ASSERT_EQ(0, crash_call(reinterpret_cast<uintptr_t>(middle_ptr)));
_exit(0);
});
// Unmap the two maps.
ASSERT_EQ(0, munmap(start_ptr, getpagesize()));
void* end_ptr =
reinterpret_cast<void*>(reinterpret_cast<uintptr_t>(start_ptr) + 2 * getpagesize());
ASSERT_EQ(0, munmap(end_ptr, getpagesize()));
unique_fd output_fd;
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGSEGV);
int intercept_result;
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
std::string match_str = R"(signal 11 \(SIGSEGV\), code 1 \(SEGV_MAPERR\), fault addr 0x)";
match_str += format_full_pointer(reinterpret_cast<uintptr_t>(middle_ptr));
ASSERT_MATCH(result, match_str);
ASSERT_MATCH(result, R"(\nmemory map \(.*\): \(fault address prefixed with --->)\n)");
match_str = android::base::StringPrintf(
R"( %s.*\n--->Fault address falls at %s between mapped regions\n %s)",
format_pointer(start_ptr).c_str(), format_pointer(middle_ptr).c_str(),
format_pointer(end_ptr).c_str());
ASSERT_MATCH(result, match_str);
}
// Verify that a fault address happens in the correct map.
TEST_F(CrasherTest, fault_address_in_map) {
// Create a map before the fork so it will be present in the child.
void* ptr = mmap(nullptr, getpagesize(), 0, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
ASSERT_NE(MAP_FAILED, ptr);
StartProcess([ptr]() {
ASSERT_EQ(0, crash_call(reinterpret_cast<uintptr_t>(ptr)));
_exit(0);
});
ASSERT_EQ(0, munmap(ptr, getpagesize()));
unique_fd output_fd;
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGSEGV);
int intercept_result;
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
std::string match_str = R"(signal 11 \(SIGSEGV\), code 2 \(SEGV_ACCERR\), fault addr 0x)";
match_str += format_full_pointer(reinterpret_cast<uintptr_t>(ptr));
ASSERT_MATCH(result, match_str);
ASSERT_MATCH(result, R"(\nmemory map \(.*\): \(fault address prefixed with --->)\n)");
match_str = android::base::StringPrintf(R"(\n--->%s.*\n)", format_pointer(ptr).c_str());
ASSERT_MATCH(result, match_str);
}
static constexpr uint32_t kDexData[] = {
0x0a786564, 0x00383330, 0xc98b3ab8, 0xf3749d94, 0xaecca4d8, 0xffc7b09a, 0xdca9ca7f, 0x5be5deab,
0x00000220, 0x00000070, 0x12345678, 0x00000000, 0x00000000, 0x0000018c, 0x00000008, 0x00000070,
0x00000004, 0x00000090, 0x00000002, 0x000000a0, 0x00000000, 0x00000000, 0x00000003, 0x000000b8,
0x00000001, 0x000000d0, 0x00000130, 0x000000f0, 0x00000122, 0x0000012a, 0x00000132, 0x00000146,
0x00000151, 0x00000154, 0x00000158, 0x0000016d, 0x00000001, 0x00000002, 0x00000004, 0x00000006,
0x00000004, 0x00000002, 0x00000000, 0x00000005, 0x00000002, 0x0000011c, 0x00000000, 0x00000000,
0x00010000, 0x00000007, 0x00000001, 0x00000000, 0x00000000, 0x00000001, 0x00000001, 0x00000000,
0x00000003, 0x00000000, 0x0000017e, 0x00000000, 0x00010001, 0x00000001, 0x00000173, 0x00000004,
0x00021070, 0x000e0000, 0x00010001, 0x00000000, 0x00000178, 0x00000001, 0x0000000e, 0x00000001,
0x3c060003, 0x74696e69, 0x4c06003e, 0x6e69614d, 0x4c12003b, 0x6176616a, 0x6e616c2f, 0x624f2f67,
0x7463656a, 0x4d09003b, 0x2e6e6961, 0x6176616a, 0x00560100, 0x004c5602, 0x6a4c5b13, 0x2f617661,
0x676e616c, 0x7274532f, 0x3b676e69, 0x616d0400, 0x01006e69, 0x000e0700, 0x07000103, 0x0000000e,
0x81000002, 0x01f00480, 0x02880901, 0x0000000c, 0x00000000, 0x00000001, 0x00000000, 0x00000001,
0x00000008, 0x00000070, 0x00000002, 0x00000004, 0x00000090, 0x00000003, 0x00000002, 0x000000a0,
0x00000005, 0x00000003, 0x000000b8, 0x00000006, 0x00000001, 0x000000d0, 0x00002001, 0x00000002,
0x000000f0, 0x00001001, 0x00000001, 0x0000011c, 0x00002002, 0x00000008, 0x00000122, 0x00002003,
0x00000002, 0x00000173, 0x00002000, 0x00000001, 0x0000017e, 0x00001000, 0x00000001, 0x0000018c,
};
TEST_F(CrasherTest, verify_dex_pc_with_function_name) {
StartProcess([]() {
TemporaryDir td;
std::string tmp_so_name;
if (!CopySharedLibrary(td.path, &tmp_so_name)) {
_exit(1);
}
// In order to cause libunwindstack to look for this __dex_debug_descriptor
// move the library to which has a basename of libart.so.
std::string art_so_name = android::base::Dirname(tmp_so_name) + "/libart.so";
ASSERT_EQ(0, rename(tmp_so_name.c_str(), art_so_name.c_str()));
void* handle = dlopen(art_so_name.c_str(), RTLD_NOW | RTLD_LOCAL);
if (handle == nullptr) {
_exit(1);
}
void* ptr =
mmap(nullptr, sizeof(kDexData), PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
ASSERT_TRUE(ptr != MAP_FAILED);
memcpy(ptr, kDexData, sizeof(kDexData));
prctl(PR_SET_VMA, PR_SET_VMA_ANON_NAME, ptr, sizeof(kDexData), "dex");
JITCodeEntry dex_entry = {.symfile_addr = reinterpret_cast<uintptr_t>(ptr),
.symfile_size = sizeof(kDexData)};
JITDescriptor* dex_debug =
reinterpret_cast<JITDescriptor*>(dlsym(handle, "__dex_debug_descriptor"));
ASSERT_TRUE(dex_debug != nullptr);
dex_debug->version = 1;
dex_debug->action_flag = 0;
dex_debug->relevant_entry = 0;
dex_debug->first_entry = reinterpret_cast<uintptr_t>(&dex_entry);
// This sets the magic dex pc value for register 0, using the value
// of register 1 + 0x102.
asm(".cfi_escape "
"0x16 /* DW_CFA_val_expression */, 0, 0x0a /* size */,"
"0x0c /* DW_OP_const4u */, 0x44, 0x45, 0x58, 0x31, /* magic = 'DEX1' */"
"0x13 /* DW_OP_drop */,"
"0x92 /* DW_OP_bregx */, 1, 0x82, 0x02 /* 2-byte SLEB128 */");
// For each different architecture, set register one to the dex ptr mmap
// created above. Then do a nullptr dereference to force a crash.
#if defined(__arm__)
asm volatile(
"mov r1, %[base]\n"
"mov r2, #0\n"
"str r2, [r2]\n"
: [base] "+r"(ptr)
:
: "r1", "r2", "memory");
#elif defined(__aarch64__)
asm volatile(
"mov x1, %[base]\n"
"mov x2, #0\n"
"str xzr, [x2]\n"
: [base] "+r"(ptr)
:
: "x1", "x2", "memory");
#elif defined(__riscv)
// TODO: x1 is ra (the link register) on riscv64, so this might have
// unintended consequences, but we'll need to change the .cfi_escape if so.
asm volatile(
"mv x1, %[base]\n"
"sw zero, 0(zero)\n"
: [base] "+r"(ptr)
:
: "x1", "memory");
#elif defined(__i386__)
asm volatile(
"mov %[base], %%ecx\n"
"movl $0, 0\n"
: [base] "+r"(ptr)
:
: "ecx", "memory");
#elif defined(__x86_64__)
asm volatile(
"mov %[base], %%rdx\n"
"movq $0, 0\n"
: [base] "+r"(ptr)
:
: "rdx", "memory");
#else
#error "Unsupported architecture"
#endif
_exit(0);
});
unique_fd output_fd;
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGSEGV);
int intercept_result;
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
// Verify the process crashed properly.
ASSERT_MATCH(result, R"(signal 11 \(SIGSEGV\), code 1 \(SEGV_MAPERR\), fault addr 0x0*)");
// Now verify that the dex_pc frame includes a proper function name.
ASSERT_MATCH(result, R"( \[anon:dex\] \(Main\.\<init\>\+2)");
}
static std::string format_map_pointer(uintptr_t ptr) {
#if defined(__LP64__)
return android::base::StringPrintf("%08x'%08x", static_cast<uint32_t>(ptr >> 32),
static_cast<uint32_t>(ptr & 0xffffffff));
#else
return android::base::StringPrintf("%08x", ptr);
#endif
}
// Verify that map data is properly formatted.
TEST_F(CrasherTest, verify_map_format) {
// Create multiple maps to make sure that the map data is formatted properly.
void* none_map = mmap(nullptr, getpagesize(), 0, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
ASSERT_NE(MAP_FAILED, none_map);
void* r_map = mmap(nullptr, getpagesize(), PROT_READ, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
ASSERT_NE(MAP_FAILED, r_map);
void* w_map = mmap(nullptr, getpagesize(), PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
ASSERT_NE(MAP_FAILED, w_map);
void* x_map = mmap(nullptr, getpagesize(), PROT_EXEC, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
ASSERT_NE(MAP_FAILED, x_map);
TemporaryFile tf;
ASSERT_EQ(0x2000, lseek(tf.fd, 0x2000, SEEK_SET));
char c = 'f';
ASSERT_EQ(1, write(tf.fd, &c, 1));
ASSERT_EQ(0x5000, lseek(tf.fd, 0x5000, SEEK_SET));
ASSERT_EQ(1, write(tf.fd, &c, 1));
ASSERT_EQ(0, lseek(tf.fd, 0, SEEK_SET));
void* file_map = mmap(nullptr, 0x3001, PROT_READ, MAP_PRIVATE, tf.fd, 0x2000);
ASSERT_NE(MAP_FAILED, file_map);
StartProcess([]() { abort(); });
ASSERT_EQ(0, munmap(none_map, getpagesize()));
ASSERT_EQ(0, munmap(r_map, getpagesize()));
ASSERT_EQ(0, munmap(w_map, getpagesize()));
ASSERT_EQ(0, munmap(x_map, getpagesize()));
ASSERT_EQ(0, munmap(file_map, 0x3001));
unique_fd output_fd;
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGABRT);
int intercept_result;
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
std::string match_str;
// Verify none.
match_str = android::base::StringPrintf(
" %s-%s --- 0 1000\\n",
format_map_pointer(reinterpret_cast<uintptr_t>(none_map)).c_str(),
format_map_pointer(reinterpret_cast<uintptr_t>(none_map) + getpagesize() - 1).c_str());
ASSERT_MATCH(result, match_str);
// Verify read-only.
match_str = android::base::StringPrintf(
" %s-%s r-- 0 1000\\n",
format_map_pointer(reinterpret_cast<uintptr_t>(r_map)).c_str(),
format_map_pointer(reinterpret_cast<uintptr_t>(r_map) + getpagesize() - 1).c_str());
ASSERT_MATCH(result, match_str);
// Verify write-only.
match_str = android::base::StringPrintf(
" %s-%s -w- 0 1000\\n",
format_map_pointer(reinterpret_cast<uintptr_t>(w_map)).c_str(),
format_map_pointer(reinterpret_cast<uintptr_t>(w_map) + getpagesize() - 1).c_str());
ASSERT_MATCH(result, match_str);
// Verify exec-only.
match_str = android::base::StringPrintf(
" %s-%s --x 0 1000\\n",
format_map_pointer(reinterpret_cast<uintptr_t>(x_map)).c_str(),
format_map_pointer(reinterpret_cast<uintptr_t>(x_map) + getpagesize() - 1).c_str());
ASSERT_MATCH(result, match_str);
// Verify file map with non-zero offset and a name.
match_str = android::base::StringPrintf(
" %s-%s r-- 2000 4000 %s\\n",
format_map_pointer(reinterpret_cast<uintptr_t>(file_map)).c_str(),
format_map_pointer(reinterpret_cast<uintptr_t>(file_map) + 0x3fff).c_str(), tf.path);
ASSERT_MATCH(result, match_str);
}
// Verify that the tombstone map data is correct.
TEST_F(CrasherTest, verify_header) {
StartProcess([]() { abort(); });
unique_fd output_fd;
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGABRT);
int intercept_result;
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
std::string match_str = android::base::StringPrintf(
"Build fingerprint: '%s'\\nRevision: '%s'\\n",
android::base::GetProperty("ro.build.fingerprint", "unknown").c_str(),
android::base::GetProperty("ro.revision", "unknown").c_str());
match_str += android::base::StringPrintf("ABI: '%s'\n", ABI_STRING);
ASSERT_MATCH(result, match_str);
}
// Verify that the thread header is formatted properly.
TEST_F(CrasherTest, verify_thread_header) {
void* shared_map =
mmap(nullptr, sizeof(pid_t), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, -1, 0);
ASSERT_NE(MAP_FAILED, shared_map);
memset(shared_map, 0, sizeof(pid_t));
StartProcess([&shared_map]() {
std::atomic_bool tid_written;
std::thread thread([&tid_written, &shared_map]() {
pid_t tid = gettid();
memcpy(shared_map, &tid, sizeof(pid_t));
tid_written = true;
volatile bool done = false;
while (!done)
;
});
thread.detach();
while (!tid_written.load(std::memory_order_acquire))
;
abort();
});
pid_t primary_pid = crasher_pid;
unique_fd output_fd;
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGABRT);
int intercept_result;
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
// Read the tid data out.
pid_t tid;
memcpy(&tid, shared_map, sizeof(pid_t));
ASSERT_NE(0, tid);
ASSERT_EQ(0, munmap(shared_map, sizeof(pid_t)));
std::string result;
ConsumeFd(std::move(output_fd), &result);
// Verify that there are two headers, one where the tid is "primary_pid"
// and the other where the tid is "tid".
std::string match_str = android::base::StringPrintf("pid: %d, tid: %d, name: .* >>> .* <<<\\n",
primary_pid, primary_pid);
ASSERT_MATCH(result, match_str);
match_str =
android::base::StringPrintf("pid: %d, tid: %d, name: .* >>> .* <<<\\n", primary_pid, tid);
ASSERT_MATCH(result, match_str);
}
// Verify that there is a BuildID present in the map section and set properly.
TEST_F(CrasherTest, verify_build_id) {
StartProcess([]() { abort(); });
unique_fd output_fd;
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGABRT);
int intercept_result;
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
// Find every /system or /apex lib and verify the BuildID is displayed
// properly.
bool found_valid_elf = false;
std::smatch match;
std::regex build_id_regex(R"( ((/system/|/apex/)\S+) \(BuildId: ([^\)]+)\))");
for (std::string prev_file; std::regex_search(result, match, build_id_regex);
result = match.suffix()) {
if (prev_file == match[1]) {
// Already checked this file.
continue;
}
prev_file = match[1];
unwindstack::Elf elf(unwindstack::Memory::CreateFileMemory(prev_file, 0).release());
if (!elf.Init() || !elf.valid()) {
// Skipping invalid elf files.
continue;
}
ASSERT_EQ(match[3], elf.GetPrintableBuildID());
found_valid_elf = true;
}
ASSERT_TRUE(found_valid_elf) << "Did not find any elf files with valid BuildIDs to check.";
}
const char kLogMessage[] = "Should not see this log message.";
// Verify that the logd process does not read the log.
TEST_F(CrasherTest, logd_skips_reading_logs) {
StartProcess([]() {
pthread_setname_np(pthread_self(), "logd");
LOG(INFO) << kLogMessage;
abort();
});
unique_fd output_fd;
StartIntercept(&output_fd);
FinishCrasher();
AssertDeath(SIGABRT);
int intercept_result;
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
// logd should not contain our log message.
ASSERT_NOT_MATCH(result, kLogMessage);
}
// Verify that the logd process does not read the log when the non-main
// thread crashes.
TEST_F(CrasherTest, logd_skips_reading_logs_not_main_thread) {
StartProcess([]() {
pthread_setname_np(pthread_self(), "logd");
LOG(INFO) << kLogMessage;
std::thread thread([]() {
pthread_setname_np(pthread_self(), "not_logd_thread");
// Raise the signal on the side thread.
raise_debugger_signal(kDebuggerdTombstone);
});
thread.join();
_exit(0);
});
unique_fd output_fd;
StartIntercept(&output_fd, kDebuggerdTombstone);
FinishCrasher();
AssertDeath(0);
int intercept_result;
FinishIntercept(&intercept_result);
ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
std::string result;
ConsumeFd(std::move(output_fd), &result);
ASSERT_BACKTRACE_FRAME(result, "raise_debugger_signal");
ASSERT_NOT_MATCH(result, kLogMessage);
}