android_system_core/debuggerd/libdebuggerd/tombstone.cpp
Christopher Ferris 9a8c855780 Compare new unwinder to old unwinder in debuggerd.
In debuggerd, when dumping a tombstone, run the new unwinder and verify
the old and new unwinder are the same. If not, dump enough information
in the tombstones to figure out how to duplicate the failure.

Bug: 23762183

Test: Builds, ran and forced a mismatch and verified output.
Change-Id: Ia178bde64d67e623d4f35086ebda68aebbff0c3c
2017-08-11 16:37:59 -07:00

864 lines
28 KiB
C++

/*
* Copyright (C) 2012-2014 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.
*/
#define LOG_TAG "DEBUG"
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <inttypes.h>
#include <signal.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ptrace.h>
#include <sys/stat.h>
#include <time.h>
#include <memory>
#include <string>
#include <android-base/file.h>
#include <android-base/stringprintf.h>
#include <android-base/unique_fd.h>
#include <android/log.h>
#include <backtrace/Backtrace.h>
#include <backtrace/BacktraceMap.h>
#include <cutils/properties.h>
#include <log/log.h>
#include <log/logprint.h>
#include <private/android_filesystem_config.h>
#include "debuggerd/handler.h"
#include "backtrace.h"
#include "elf_utils.h"
#include "machine.h"
#include "open_files_list.h"
#include "tombstone.h"
using android::base::StringPrintf;
#define STACK_WORDS 16
#define MAX_TOMBSTONES 10
#define TOMBSTONE_DIR "/data/tombstones"
#define TOMBSTONE_TEMPLATE (TOMBSTONE_DIR"/tombstone_%02d")
static bool signal_has_si_addr(int si_signo, int si_code) {
// Manually sent signals won't have si_addr.
if (si_code == SI_USER || si_code == SI_QUEUE || si_code == SI_TKILL) {
return false;
}
switch (si_signo) {
case SIGBUS:
case SIGFPE:
case SIGILL:
case SIGSEGV:
case SIGTRAP:
return true;
default:
return false;
}
}
static const char* get_signame(int sig) {
switch (sig) {
case SIGABRT: return "SIGABRT";
case SIGBUS: return "SIGBUS";
case SIGFPE: return "SIGFPE";
case SIGILL: return "SIGILL";
case SIGSEGV: return "SIGSEGV";
#if defined(SIGSTKFLT)
case SIGSTKFLT: return "SIGSTKFLT";
#endif
case SIGSTOP: return "SIGSTOP";
case SIGSYS: return "SIGSYS";
case SIGTRAP: return "SIGTRAP";
case DEBUGGER_SIGNAL: return "<debuggerd signal>";
default: return "?";
}
}
static const char* get_sigcode(int signo, int code) {
// Try the signal-specific codes...
switch (signo) {
case SIGILL:
switch (code) {
case ILL_ILLOPC: return "ILL_ILLOPC";
case ILL_ILLOPN: return "ILL_ILLOPN";
case ILL_ILLADR: return "ILL_ILLADR";
case ILL_ILLTRP: return "ILL_ILLTRP";
case ILL_PRVOPC: return "ILL_PRVOPC";
case ILL_PRVREG: return "ILL_PRVREG";
case ILL_COPROC: return "ILL_COPROC";
case ILL_BADSTK: return "ILL_BADSTK";
}
static_assert(NSIGILL == ILL_BADSTK, "missing ILL_* si_code");
break;
case SIGBUS:
switch (code) {
case BUS_ADRALN: return "BUS_ADRALN";
case BUS_ADRERR: return "BUS_ADRERR";
case BUS_OBJERR: return "BUS_OBJERR";
case BUS_MCEERR_AR: return "BUS_MCEERR_AR";
case BUS_MCEERR_AO: return "BUS_MCEERR_AO";
}
static_assert(NSIGBUS == BUS_MCEERR_AO, "missing BUS_* si_code");
break;
case SIGFPE:
switch (code) {
case FPE_INTDIV: return "FPE_INTDIV";
case FPE_INTOVF: return "FPE_INTOVF";
case FPE_FLTDIV: return "FPE_FLTDIV";
case FPE_FLTOVF: return "FPE_FLTOVF";
case FPE_FLTUND: return "FPE_FLTUND";
case FPE_FLTRES: return "FPE_FLTRES";
case FPE_FLTINV: return "FPE_FLTINV";
case FPE_FLTSUB: return "FPE_FLTSUB";
}
static_assert(NSIGFPE == FPE_FLTSUB, "missing FPE_* si_code");
break;
case SIGSEGV:
switch (code) {
case SEGV_MAPERR: return "SEGV_MAPERR";
case SEGV_ACCERR: return "SEGV_ACCERR";
#if defined(SEGV_BNDERR)
case SEGV_BNDERR: return "SEGV_BNDERR";
#endif
#if defined(SEGV_PKUERR)
case SEGV_PKUERR: return "SEGV_PKUERR";
#endif
}
#if defined(SEGV_PKUERR)
static_assert(NSIGSEGV == SEGV_PKUERR, "missing SEGV_* si_code");
#elif defined(SEGV_BNDERR)
static_assert(NSIGSEGV == SEGV_BNDERR, "missing SEGV_* si_code");
#else
static_assert(NSIGSEGV == SEGV_ACCERR, "missing SEGV_* si_code");
#endif
break;
#if defined(SYS_SECCOMP) // Our glibc is too old, and we build this for the host too.
case SIGSYS:
switch (code) {
case SYS_SECCOMP: return "SYS_SECCOMP";
}
static_assert(NSIGSYS == SYS_SECCOMP, "missing SYS_* si_code");
break;
#endif
case SIGTRAP:
switch (code) {
case TRAP_BRKPT: return "TRAP_BRKPT";
case TRAP_TRACE: return "TRAP_TRACE";
case TRAP_BRANCH: return "TRAP_BRANCH";
case TRAP_HWBKPT: return "TRAP_HWBKPT";
}
if ((code & 0xff) == SIGTRAP) {
switch ((code >> 8) & 0xff) {
case PTRACE_EVENT_FORK:
return "PTRACE_EVENT_FORK";
case PTRACE_EVENT_VFORK:
return "PTRACE_EVENT_VFORK";
case PTRACE_EVENT_CLONE:
return "PTRACE_EVENT_CLONE";
case PTRACE_EVENT_EXEC:
return "PTRACE_EVENT_EXEC";
case PTRACE_EVENT_VFORK_DONE:
return "PTRACE_EVENT_VFORK_DONE";
case PTRACE_EVENT_EXIT:
return "PTRACE_EVENT_EXIT";
case PTRACE_EVENT_SECCOMP:
return "PTRACE_EVENT_SECCOMP";
case PTRACE_EVENT_STOP:
return "PTRACE_EVENT_STOP";
}
}
static_assert(NSIGTRAP == TRAP_HWBKPT, "missing TRAP_* si_code");
break;
}
// Then the other codes...
switch (code) {
case SI_USER: return "SI_USER";
case SI_KERNEL: return "SI_KERNEL";
case SI_QUEUE: return "SI_QUEUE";
case SI_TIMER: return "SI_TIMER";
case SI_MESGQ: return "SI_MESGQ";
case SI_ASYNCIO: return "SI_ASYNCIO";
case SI_SIGIO: return "SI_SIGIO";
case SI_TKILL: return "SI_TKILL";
case SI_DETHREAD: return "SI_DETHREAD";
}
// Then give up...
return "?";
}
static void dump_header_info(log_t* log) {
char fingerprint[PROPERTY_VALUE_MAX];
char revision[PROPERTY_VALUE_MAX];
property_get("ro.build.fingerprint", fingerprint, "unknown");
property_get("ro.revision", revision, "unknown");
_LOG(log, logtype::HEADER, "Build fingerprint: '%s'\n", fingerprint);
_LOG(log, logtype::HEADER, "Revision: '%s'\n", revision);
_LOG(log, logtype::HEADER, "ABI: '%s'\n", ABI_STRING);
}
static void dump_probable_cause(log_t* log, const siginfo_t& si) {
std::string cause;
if (si.si_signo == SIGSEGV && si.si_code == SEGV_MAPERR) {
if (si.si_addr < reinterpret_cast<void*>(4096)) {
cause = StringPrintf("null pointer dereference");
} else if (si.si_addr == reinterpret_cast<void*>(0xffff0ffc)) {
cause = "call to kuser_helper_version";
} else if (si.si_addr == reinterpret_cast<void*>(0xffff0fe0)) {
cause = "call to kuser_get_tls";
} else if (si.si_addr == reinterpret_cast<void*>(0xffff0fc0)) {
cause = "call to kuser_cmpxchg";
} else if (si.si_addr == reinterpret_cast<void*>(0xffff0fa0)) {
cause = "call to kuser_memory_barrier";
} else if (si.si_addr == reinterpret_cast<void*>(0xffff0f60)) {
cause = "call to kuser_cmpxchg64";
}
} else if (si.si_signo == SIGSYS && si.si_code == SYS_SECCOMP) {
cause = StringPrintf("seccomp prevented call to disallowed %s system call %d",
ABI_STRING, si.si_syscall);
}
if (!cause.empty()) _LOG(log, logtype::HEADER, "Cause: %s\n", cause.c_str());
}
static void dump_signal_info(log_t* log, const siginfo_t* siginfo) {
const siginfo_t& si = *siginfo;
char addr_desc[32]; // ", fault addr 0x1234"
if (signal_has_si_addr(si.si_signo, si.si_code)) {
snprintf(addr_desc, sizeof(addr_desc), "%p", si.si_addr);
} else {
snprintf(addr_desc, sizeof(addr_desc), "--------");
}
_LOG(log, logtype::HEADER, "signal %d (%s), code %d (%s), fault addr %s\n", si.si_signo,
get_signame(si.si_signo), si.si_code, get_sigcode(si.si_signo, si.si_code), addr_desc);
dump_probable_cause(log, si);
}
static void dump_signal_info(log_t* log, pid_t tid) {
siginfo_t si;
memset(&si, 0, sizeof(si));
if (ptrace(PTRACE_GETSIGINFO, tid, 0, &si) == -1) {
ALOGE("cannot get siginfo: %s\n", strerror(errno));
return;
}
dump_signal_info(log, &si);
}
static void dump_thread_info(log_t* log, pid_t pid, pid_t tid, const char* process_name,
const char* thread_name) {
// Blacklist logd, logd.reader, logd.writer, logd.auditd, logd.control ...
// TODO: Why is this controlled by thread name?
if (strcmp(thread_name, "logd") == 0 || strncmp(thread_name, "logd.", 4) == 0) {
log->should_retrieve_logcat = false;
}
_LOG(log, logtype::HEADER, "pid: %d, tid: %d, name: %s >>> %s <<<\n", pid, tid, thread_name,
process_name);
}
static void dump_stack_segment(
Backtrace* backtrace, log_t* log, uintptr_t* sp, size_t words, int label) {
// Read the data all at once.
word_t stack_data[words];
size_t bytes_read = backtrace->Read(*sp, reinterpret_cast<uint8_t*>(&stack_data[0]), sizeof(word_t) * words);
words = bytes_read / sizeof(word_t);
std::string line;
for (size_t i = 0; i < words; i++) {
line = " ";
if (i == 0 && label >= 0) {
// Print the label once.
line += StringPrintf("#%02d ", label);
} else {
line += " ";
}
line += StringPrintf("%" PRIPTR " %" PRIPTR, *sp, stack_data[i]);
backtrace_map_t map;
backtrace->FillInMap(stack_data[i], &map);
if (BacktraceMap::IsValid(map) && !map.name.empty()) {
line += " " + map.name;
uintptr_t offset = 0;
std::string func_name(backtrace->GetFunctionName(stack_data[i], &offset, &map));
if (!func_name.empty()) {
line += " (" + func_name;
if (offset) {
line += StringPrintf("+%" PRIuPTR, offset);
}
line += ')';
}
}
_LOG(log, logtype::STACK, "%s\n", line.c_str());
*sp += sizeof(word_t);
}
}
static void dump_stack(Backtrace* backtrace, log_t* log) {
size_t first = 0, last;
for (size_t i = 0; i < backtrace->NumFrames(); i++) {
const backtrace_frame_data_t* frame = backtrace->GetFrame(i);
if (frame->sp) {
if (!first) {
first = i+1;
}
last = i;
}
}
if (!first) {
return;
}
first--;
// Dump a few words before the first frame.
word_t sp = backtrace->GetFrame(first)->sp - STACK_WORDS * sizeof(word_t);
dump_stack_segment(backtrace, log, &sp, STACK_WORDS, -1);
// Dump a few words from all successive frames.
// Only log the first 3 frames, put the rest in the tombstone.
for (size_t i = first; i <= last; i++) {
const backtrace_frame_data_t* frame = backtrace->GetFrame(i);
if (sp != frame->sp) {
_LOG(log, logtype::STACK, " ........ ........\n");
sp = frame->sp;
}
if (i == last) {
dump_stack_segment(backtrace, log, &sp, STACK_WORDS, i);
if (sp < frame->sp + frame->stack_size) {
_LOG(log, logtype::STACK, " ........ ........\n");
}
} else {
size_t words = frame->stack_size / sizeof(word_t);
if (words == 0) {
words = 1;
} else if (words > STACK_WORDS) {
words = STACK_WORDS;
}
dump_stack_segment(backtrace, log, &sp, words, i);
}
}
}
static std::string get_addr_string(uintptr_t addr) {
std::string addr_str;
#if defined(__LP64__)
addr_str = StringPrintf("%08x'%08x",
static_cast<uint32_t>(addr >> 32),
static_cast<uint32_t>(addr & 0xffffffff));
#else
addr_str = StringPrintf("%08x", addr);
#endif
return addr_str;
}
static void dump_abort_message(Backtrace* backtrace, log_t* log, uintptr_t address) {
if (address == 0) {
return;
}
address += sizeof(size_t); // Skip the buffer length.
char msg[512];
memset(msg, 0, sizeof(msg));
char* p = &msg[0];
while (p < &msg[sizeof(msg)]) {
word_t data;
size_t len = sizeof(word_t);
if (!backtrace->ReadWord(address, &data)) {
break;
}
address += sizeof(word_t);
while (len > 0 && (*p++ = (data >> (sizeof(word_t) - len) * 8) & 0xff) != 0) {
len--;
}
}
msg[sizeof(msg) - 1] = '\0';
_LOG(log, logtype::HEADER, "Abort message: '%s'\n", msg);
}
static void dump_all_maps(Backtrace* backtrace, BacktraceMap* map, log_t* log, pid_t tid) {
bool print_fault_address_marker = false;
uintptr_t addr = 0;
siginfo_t si;
memset(&si, 0, sizeof(si));
if (ptrace(PTRACE_GETSIGINFO, tid, 0, &si) != -1) {
print_fault_address_marker = signal_has_si_addr(si.si_signo, si.si_code);
addr = reinterpret_cast<uintptr_t>(si.si_addr);
} else {
ALOGE("Cannot get siginfo for %d: %s\n", tid, strerror(errno));
}
ScopedBacktraceMapIteratorLock lock(map);
_LOG(log, logtype::MAPS, "\n");
if (!print_fault_address_marker) {
_LOG(log, logtype::MAPS, "memory map:\n");
} else {
_LOG(log, logtype::MAPS, "memory map: (fault address prefixed with --->)\n");
if (map->begin() != map->end() && addr < map->begin()->start) {
_LOG(log, logtype::MAPS, "--->Fault address falls at %s before any mapped regions\n",
get_addr_string(addr).c_str());
print_fault_address_marker = false;
}
}
std::string line;
for (BacktraceMap::const_iterator it = map->begin(); it != map->end(); ++it) {
line = " ";
if (print_fault_address_marker) {
if (addr < it->start) {
_LOG(log, logtype::MAPS, "--->Fault address falls at %s between mapped regions\n",
get_addr_string(addr).c_str());
print_fault_address_marker = false;
} else if (addr >= it->start && addr < it->end) {
line = "--->";
print_fault_address_marker = false;
}
}
line += get_addr_string(it->start) + '-' + get_addr_string(it->end - 1) + ' ';
if (it->flags & PROT_READ) {
line += 'r';
} else {
line += '-';
}
if (it->flags & PROT_WRITE) {
line += 'w';
} else {
line += '-';
}
if (it->flags & PROT_EXEC) {
line += 'x';
} else {
line += '-';
}
line += StringPrintf(" %8" PRIxPTR " %8" PRIxPTR, it->offset, it->end - it->start);
bool space_needed = true;
if (it->name.length() > 0) {
space_needed = false;
line += " " + it->name;
std::string build_id;
if ((it->flags & PROT_READ) && elf_get_build_id(backtrace, it->start, &build_id)) {
line += " (BuildId: " + build_id + ")";
}
}
if (it->load_bias != 0) {
if (space_needed) {
line += ' ';
}
line += StringPrintf(" (load bias 0x%" PRIxPTR ")", it->load_bias);
}
_LOG(log, logtype::MAPS, "%s\n", line.c_str());
}
if (print_fault_address_marker) {
_LOG(log, logtype::MAPS, "--->Fault address falls at %s after any mapped regions\n",
get_addr_string(addr).c_str());
}
}
static void dump_backtrace_and_stack(Backtrace* backtrace, log_t* log) {
if (backtrace->NumFrames()) {
_LOG(log, logtype::BACKTRACE, "\nbacktrace:\n");
dump_backtrace_to_log(backtrace, log, " ");
_LOG(log, logtype::STACK, "\nstack:\n");
dump_stack(backtrace, log);
}
}
// Weak noop implementation, real implementations are in <arch>/machine.cpp.
__attribute__((weak)) void dump_registers(log_t* log, const ucontext_t*) {
_LOG(log, logtype::REGISTERS, " register dumping unimplemented on this architecture");
}
static bool verify_backtraces_equal(Backtrace* back1, Backtrace* back2) {
if (back1->NumFrames() != back2->NumFrames()) {
return false;
}
std::string back1_str;
std::string back2_str;
for (size_t i = 0; i < back1->NumFrames(); i++) {
back1_str += back1->FormatFrameData(i);
back2_str += back2->FormatFrameData(i);
}
return back1_str == back2_str;
}
static void log_mismatch_data(log_t* log, Backtrace* backtrace) {
_LOG(log, logtype::THREAD, "MISMATCH: This unwind is different.\n");
if (backtrace->NumFrames() == 0) {
_LOG(log, logtype::THREAD, "MISMATCH: No frames in new backtrace.\n");
return;
}
_LOG(log, logtype::THREAD, "MISMATCH: Backtrace from new unwinder.\n");
for (size_t i = 0; i < backtrace->NumFrames(); i++) {
_LOG(log, logtype::THREAD, "MISMATCH: %s\n", backtrace->FormatFrameData(i).c_str());
}
// Get the stack trace up to 8192 bytes.
std::vector<uint64_t> buffer(8192 / sizeof(uint64_t));
size_t bytes =
backtrace->Read(backtrace->GetFrame(0)->sp, reinterpret_cast<uint8_t*>(buffer.data()),
buffer.size() * sizeof(uint64_t));
std::string log_data;
for (size_t i = 0; i < bytes / sizeof(uint64_t); i++) {
if ((i % 4) == 0) {
if (!log_data.empty()) {
_LOG(log, logtype::THREAD, "MISMATCH: stack_data%s\n", log_data.c_str());
log_data = "";
}
}
log_data += android::base::StringPrintf(" 0x%016" PRIx64, buffer[i]);
}
if (!log_data.empty()) {
_LOG(log, logtype::THREAD, "MISMATCH: data%s\n", log_data.c_str());
}
// If there is any leftover (bytes % sizeof(uint64_t) != 0, ignore it for now.
}
static bool dump_thread(log_t* log, pid_t pid, pid_t tid, const std::string& process_name,
const std::string& thread_name, BacktraceMap* map, BacktraceMap* map_new,
uintptr_t abort_msg_address, bool primary_thread) {
log->current_tid = tid;
if (!primary_thread) {
_LOG(log, logtype::THREAD, "--- --- --- --- --- --- --- --- --- --- --- --- --- --- --- ---\n");
}
dump_thread_info(log, pid, tid, process_name.c_str(), thread_name.c_str());
dump_signal_info(log, tid);
std::unique_ptr<Backtrace> backtrace(Backtrace::Create(pid, tid, map));
if (primary_thread) {
dump_abort_message(backtrace.get(), log, abort_msg_address);
}
dump_registers(log, tid);
bool matches = true;
if (backtrace->Unwind(0)) {
// Use the new method and verify it is the same as old.
std::unique_ptr<Backtrace> backtrace_new(Backtrace::CreateNew(pid, tid, map_new));
if (!backtrace_new->Unwind(0)) {
_LOG(log, logtype::THREAD, "Failed to unwind with new unwinder: %s\n",
backtrace_new->GetErrorString(backtrace_new->GetError()).c_str());
matches = false;
} else if (!verify_backtraces_equal(backtrace.get(), backtrace_new.get())) {
log_mismatch_data(log, backtrace_new.get());
matches = false;
}
dump_backtrace_and_stack(backtrace.get(), log);
} else {
ALOGE("Unwind failed: pid = %d, tid = %d", pid, tid);
}
if (primary_thread) {
dump_memory_and_code(log, backtrace.get());
if (map) {
dump_all_maps(backtrace.get(), map, log, tid);
}
}
log->current_tid = log->crashed_tid;
return matches;
}
// Reads the contents of the specified log device, filters out the entries
// that don't match the specified pid, and writes them to the tombstone file.
//
// If "tail" is non-zero, log the last "tail" number of lines.
static EventTagMap* g_eventTagMap = NULL;
static void dump_log_file(
log_t* log, pid_t pid, const char* filename, unsigned int tail) {
bool first = true;
struct logger_list* logger_list;
if (!log->should_retrieve_logcat) {
return;
}
logger_list = android_logger_list_open(
android_name_to_log_id(filename), ANDROID_LOG_RDONLY | ANDROID_LOG_NONBLOCK, tail, pid);
if (!logger_list) {
ALOGE("Unable to open %s: %s\n", filename, strerror(errno));
return;
}
struct log_msg log_entry;
while (true) {
ssize_t actual = android_logger_list_read(logger_list, &log_entry);
struct logger_entry* entry;
if (actual < 0) {
if (actual == -EINTR) {
// interrupted by signal, retry
continue;
} else if (actual == -EAGAIN) {
// non-blocking EOF; we're done
break;
} else {
ALOGE("Error while reading log: %s\n", strerror(-actual));
break;
}
} else if (actual == 0) {
ALOGE("Got zero bytes while reading log: %s\n", strerror(errno));
break;
}
// NOTE: if you ALOGV something here, this will spin forever,
// because you will be writing as fast as you're reading. Any
// high-frequency debug diagnostics should just be written to
// the tombstone file.
entry = &log_entry.entry_v1;
if (first) {
_LOG(log, logtype::LOGS, "--------- %slog %s\n",
tail ? "tail end of " : "", filename);
first = false;
}
// Msg format is: <priority:1><tag:N>\0<message:N>\0
//
// We want to display it in the same format as "logcat -v threadtime"
// (although in this case the pid is redundant).
static const char* kPrioChars = "!.VDIWEFS";
unsigned hdr_size = log_entry.entry.hdr_size;
if (!hdr_size) {
hdr_size = sizeof(log_entry.entry_v1);
}
if ((hdr_size < sizeof(log_entry.entry_v1)) ||
(hdr_size > sizeof(log_entry.entry))) {
continue;
}
char* msg = reinterpret_cast<char*>(log_entry.buf) + hdr_size;
char timeBuf[32];
time_t sec = static_cast<time_t>(entry->sec);
struct tm tmBuf;
struct tm* ptm;
ptm = localtime_r(&sec, &tmBuf);
strftime(timeBuf, sizeof(timeBuf), "%m-%d %H:%M:%S", ptm);
if (log_entry.id() == LOG_ID_EVENTS) {
if (!g_eventTagMap) {
g_eventTagMap = android_openEventTagMap(NULL);
}
AndroidLogEntry e;
char buf[512];
android_log_processBinaryLogBuffer(entry, &e, g_eventTagMap, buf, sizeof(buf));
_LOG(log, logtype::LOGS, "%s.%03d %5d %5d %c %-8.*s: %s\n",
timeBuf, entry->nsec / 1000000, entry->pid, entry->tid,
'I', (int)e.tagLen, e.tag, e.message);
continue;
}
unsigned char prio = msg[0];
char* tag = msg + 1;
msg = tag + strlen(tag) + 1;
// consume any trailing newlines
char* nl = msg + strlen(msg) - 1;
while (nl >= msg && *nl == '\n') {
*nl-- = '\0';
}
char prioChar = (prio < strlen(kPrioChars) ? kPrioChars[prio] : '?');
// Look for line breaks ('\n') and display each text line
// on a separate line, prefixed with the header, like logcat does.
do {
nl = strchr(msg, '\n');
if (nl) {
*nl = '\0';
++nl;
}
_LOG(log, logtype::LOGS, "%s.%03d %5d %5d %c %-8s: %s\n",
timeBuf, entry->nsec / 1000000, entry->pid, entry->tid,
prioChar, tag, msg);
} while ((msg = nl));
}
android_logger_list_free(logger_list);
}
// Dumps the logs generated by the specified pid to the tombstone, from both
// "system" and "main" log devices. Ideally we'd interleave the output.
static void dump_logs(log_t* log, pid_t pid, unsigned int tail) {
dump_log_file(log, pid, "system", tail);
dump_log_file(log, pid, "main", tail);
}
// Dumps all information about the specified pid to the tombstone.
static void dump_crash(log_t* log, BacktraceMap* map, BacktraceMap* map_new,
const OpenFilesList* open_files, pid_t pid, pid_t tid,
const std::string& process_name, const std::map<pid_t, std::string>& threads,
uintptr_t abort_msg_address) {
// don't copy log messages to tombstone unless this is a dev device
char value[PROPERTY_VALUE_MAX];
property_get("ro.debuggable", value, "0");
bool want_logs = (value[0] == '1');
_LOG(log, logtype::HEADER,
"*** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***\n");
dump_header_info(log);
bool new_unwind_matches = dump_thread(log, pid, tid, process_name, threads.find(tid)->second, map,
map_new, abort_msg_address, true);
if (want_logs) {
dump_logs(log, pid, 5);
}
for (const auto& it : threads) {
pid_t thread_tid = it.first;
const std::string& thread_name = it.second;
if (thread_tid != tid) {
bool match =
dump_thread(log, pid, thread_tid, process_name, thread_name, map, map_new, 0, false);
new_unwind_matches = new_unwind_matches && match;
}
}
if (open_files) {
_LOG(log, logtype::OPEN_FILES, "\nopen files:\n");
dump_open_files_list_to_log(*open_files, log, " ");
}
if (want_logs) {
dump_logs(log, pid, 0);
}
if (!new_unwind_matches) {
_LOG(log, logtype::THREAD, "MISMATCH: New and old unwinder do not agree.\n");
_LOG(log, logtype::THREAD, "MISMATCH: If you see this please file a bug in:\n");
_LOG(log, logtype::THREAD,
"MISMATCH: Android > Android OS & Apps > Runtime > native > tools "
"(debuggerd/gdb/init/simpleperf/strace/valgrind)\n");
_LOG(log, logtype::THREAD, "MISMATCH: and attach this tombstone.\n");
}
}
// open_tombstone - find an available tombstone slot, if any, of the
// form tombstone_XX where XX is 00 to MAX_TOMBSTONES-1, inclusive. If no
// file is available, we reuse the least-recently-modified file.
int open_tombstone(std::string* out_path) {
// In a single pass, find an available slot and, in case none
// exist, find and record the least-recently-modified file.
char path[128];
int fd = -1;
int oldest = -1;
struct stat oldest_sb;
for (int i = 0; i < MAX_TOMBSTONES; i++) {
snprintf(path, sizeof(path), TOMBSTONE_TEMPLATE, i);
struct stat sb;
if (stat(path, &sb) == 0) {
if (oldest < 0 || sb.st_mtime < oldest_sb.st_mtime) {
oldest = i;
oldest_sb.st_mtime = sb.st_mtime;
}
continue;
}
if (errno != ENOENT) continue;
fd = open(path, O_CREAT | O_EXCL | O_WRONLY | O_NOFOLLOW | O_CLOEXEC, 0600);
if (fd < 0) continue; // raced ?
if (out_path) {
*out_path = path;
}
fchown(fd, AID_SYSTEM, AID_SYSTEM);
return fd;
}
if (oldest < 0) {
ALOGE("debuggerd: failed to find a valid tombstone, default to using tombstone 0.\n");
oldest = 0;
}
// we didn't find an available file, so we clobber the oldest one
snprintf(path, sizeof(path), TOMBSTONE_TEMPLATE, oldest);
fd = open(path, O_CREAT | O_TRUNC | O_WRONLY | O_NOFOLLOW | O_CLOEXEC, 0600);
if (fd < 0) {
ALOGE("debuggerd: failed to open tombstone file '%s': %s\n", path, strerror(errno));
return -1;
}
if (out_path) {
*out_path = path;
}
fchown(fd, AID_SYSTEM, AID_SYSTEM);
return fd;
}
void engrave_tombstone(int tombstone_fd, BacktraceMap* map, BacktraceMap* map_new,
const OpenFilesList* open_files, pid_t pid, pid_t tid,
const std::string& process_name, const std::map<pid_t, std::string>& threads,
uintptr_t abort_msg_address, std::string* amfd_data) {
log_t log;
log.current_tid = tid;
log.crashed_tid = tid;
log.tfd = tombstone_fd;
log.amfd_data = amfd_data;
dump_crash(&log, map, map_new, open_files, pid, tid, process_name, threads, abort_msg_address);
}
void engrave_tombstone_ucontext(int tombstone_fd, uintptr_t abort_msg_address, siginfo_t* siginfo,
ucontext_t* ucontext) {
pid_t pid = getpid();
pid_t tid = gettid();
log_t log;
log.current_tid = tid;
log.crashed_tid = tid;
log.tfd = tombstone_fd;
log.amfd_data = nullptr;
char thread_name[16];
char process_name[128];
read_with_default("/proc/self/comm", thread_name, sizeof(thread_name), "<unknown>");
read_with_default("/proc/self/cmdline", process_name, sizeof(process_name), "<unknown>");
_LOG(&log, logtype::HEADER, "*** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***\n");
dump_header_info(&log);
dump_thread_info(&log, pid, tid, thread_name, process_name);
dump_signal_info(&log, siginfo);
std::unique_ptr<Backtrace> backtrace(Backtrace::Create(pid, tid));
dump_abort_message(backtrace.get(), &log, abort_msg_address);
dump_registers(&log, ucontext);
// TODO: Dump registers from the ucontext.
if (backtrace->Unwind(0, ucontext)) {
dump_backtrace_and_stack(backtrace.get(), &log);
} else {
ALOGE("Unwind failed: pid = %d, tid = %d", pid, tid);
}
}