/* * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "crash_test.h" #include "debuggerd/handler.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, &new_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"(\+)"); // Enable GWP-ASan at the start of this process. GWP-ASan is enabled using // process sampling, so we need to ensure we force GWP-ASan on. __attribute__((constructor)) static void enable_gwp_asan() { bool force = true; android_mallopt(M_INITIALIZE_GWP_ASAN, &force, sizeof(force)); } 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; } 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 function, std::function 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 function, std::function 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(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 0xdead)"); if (mte_supported()) { // Test that the default TAGGED_ADDR_CTRL value is set. ASSERT_MATCH(result, R"(tagged_addr_ctrl: 000000000007fff3)"); } } TEST_F(CrasherTest, tagged_fault_addr) { #if !defined(__aarch64__) GTEST_SKIP() << "Requires aarch64"; #endif int intercept_result; unique_fd output_fd; StartProcess([]() { *reinterpret_cast(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 (0x100000000000dead|0xdead))"); } // Marked as weak to prevent the compiler from removing the malloc in the caller. In theory, the // compiler could still clobber the argument register before trapping, but that's unlikely. __attribute__((weak)) void CrasherTest::Trap(void* ptr ATTRIBUTE_UNUSED) { __builtin_trap(); } TEST_F(CrasherTest, heap_addr_in_register) { #if defined(__i386__) GTEST_SKIP() << "architecture does not pass arguments in registers"; #endif 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(__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(); } } #endif // Number of iterations required to reliably guarantee a GWP-ASan crash. // GWP-ASan's sample rate is not truly nondeterministic, it initialises a // thread-local counter at 2*SampleRate, and decrements on each malloc(). Once // the counter reaches zero, we provide a sampled allocation. Then, double that // figure to allow for left/right allocation alignment, as this is done randomly // without bias. #define GWP_ASAN_ITERATIONS_TO_ENSURE_CRASH (0x20000) 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 {}; 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 */ 7, /* free_before_access */ true, /* access_offset */ 1, "Use After Free, 1 byte into a 7-byte allocation"}, {/* alloc_size */ 7, /* free_before_access */ false, /* access_offset */ 16, "Buffer Overflow, 9 bytes right of a 7-byte allocation"}, {/* alloc_size */ 16, /* free_before_access */ false, /* access_offset */ -1, "Buffer Underflow, 1 byte left of a 16-byte allocation"}, }; INSTANTIATE_TEST_SUITE_P(GwpAsanTests, GwpAsanCrasherTest, testing::ValuesIn(gwp_asan_tests)); TEST_P(GwpAsanCrasherTest, gwp_asan_uaf) { 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."; } GwpAsanTestParameters params = GetParam(); LogcatCollector logcat_collector; int intercept_result; unique_fd output_fd; StartProcess([¶ms]() { for (unsigned i = 0; i < GWP_ASAN_ITERATIONS_TO_ENSURE_CRASH; ++i) { volatile char* p = reinterpret_cast(malloc(params.alloc_size)); if (params.free_before_access) free(static_cast(const_cast(p))); p[params.access_offset] = 42; if (!params.free_before_access) free(static_cast(const_cast(p))); } }); StartIntercept(&output_fd); FinishCrasher(); AssertDeath(SIGSEGV); FinishIntercept(&intercept_result); ASSERT_EQ(1, intercept_result) << "tombstoned reported failure"; std::vector log_sources(2); ConsumeFd(std::move(output_fd), &log_sources[0]); logcat_collector.Collect(&log_sources[1]); 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)"); } } struct SizeParamCrasherTest : CrasherTest, testing::WithParamInterface {}; 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 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 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_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 allocs; for (int i = 0; i != 4096; ++i) { uintptr_t alloc = reinterpret_cast(malloc(16)); auto it = allocs.insert(alloc).first; if (it != allocs.begin() && *std::prev(it) + 128 > alloc) { *reinterpret_cast(*std::prev(it) + 16) = 42; } if (std::next(it) != allocs.end() && alloc + 128 > *std::next(it)) { *reinterpret_cast(alloc + 16) = 42; } } }); StartIntercept(&output_fd); FinishCrasher(); AssertDeath(SIGSEGV); FinishIntercept(&intercept_result); ASSERT_EQ(1, intercept_result) << "tombstoned reported failure"; std::vector 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 probability.")); // 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(mapping); if (mapping == MAP_FAILED) { return 0; } mprotect(reinterpret_cast(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(CreateTagMapping())); }); StartIntercept(&output_fd); FinishCrasher(); AssertDeath(SIGTRAP); 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(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(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(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(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 0xdead)"); } 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 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 pid_t seccomp_fork_impl(void (*prejail)()) { 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"; } ScopedMinijail jail{minijail_new()}; if (!jail) { LOG(FATAL) << "failed to create minijail"; } minijail_no_new_privs(jail.get()); minijail_log_seccomp_filter_failures(jail.get()); minijail_use_seccomp_filter(jail.get()); minijail_parse_seccomp_filters_from_fd(jail.get(), tmp_fd.release()); 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 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 vec; for (int i = 0; i < 512; ++i) { char* buf = static_cast(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; } TEST_F(CrasherTest, seccomp_tombstone) { int intercept_result; unique_fd output_fd; static const auto dump_type = kDebuggerdTombstone; StartProcess( []() { 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"); } 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_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_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); } 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 start(false); std::vector 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 { std::map 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 bool CopySharedLibrary(const char* tmp_dir, std::string* tmp_so_name) { 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) + "./"; } test_lib += "libcrash_test.so"; *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; StartProcess([]() { TemporaryDir td; std::string tmp_so_name; 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(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 )"); } 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 tombstone_file; std::unique_ptr 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(ptr >> 32), static_cast(ptr & 0xffffffff)); #else return android::base::StringPrintf("%08x", static_cast(ptr & 0xffffffff)); #endif } static std::string format_pointer(void* ptr) { return format_pointer(reinterpret_cast(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(ptr)); } __attribute__((__noinline__)) int crash_call(uintptr_t ptr) { int* crash_ptr = reinterpret_cast(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 0x1024)"); 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) { 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 )"; match_str += android::base::StringPrintf("0x%" PRIxPTR, 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(reinterpret_cast(start_ptr) + getpagesize()); ASSERT_EQ(0, munmap(middle_ptr, getpagesize())); StartProcess([middle_ptr]() { ASSERT_EQ(0, crash_call(reinterpret_cast(middle_ptr))); _exit(0); }); // Unmap the two maps. ASSERT_EQ(0, munmap(start_ptr, getpagesize())); void* end_ptr = reinterpret_cast(reinterpret_cast(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 )"; match_str += android::base::StringPrintf("%p", 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(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 )"; match_str += android::base::StringPrintf("%p", 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(ptr), .symfile_size = sizeof(kDexData)}; JITDescriptor* dex_debug = reinterpret_cast(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(&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 r3, [r2]\n" : [base] "+r"(ptr) : : "r1", "r2", "r3", "memory"); #elif defined(__aarch64__) asm volatile( "mov x1, %[base]\n" "mov x2, 0\n" "str x3, [x2]\n" : [base] "+r"(ptr) : : "x1", "x2", "x3", "memory"); #elif defined(__i386__) asm volatile( "mov %[base], %%ecx\n" "movl $0, %%edi\n" "movl 0(%%edi), %%edx\n" : [base] "+r"(ptr) : : "edi", "ecx", "edx", "memory"); #elif defined(__x86_64__) asm volatile( "mov %[base], %%rdx\n" "movq 0, %%rdi\n" "movq 0(%%rdi), %%rcx\n" : [base] "+r"(ptr) : : "rcx", "rdx", "rdi", "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\.\\+2)"); }