| // Copyright (c) 2012 The Chromium OS Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "crash-reporter/crash_collector.h" |
| |
| #include <dirent.h> |
| #include <fcntl.h> // For file creation modes. |
| #include <pwd.h> // For struct passwd. |
| #include <sys/types.h> // for mode_t. |
| #include <sys/wait.h> // For waitpid. |
| #include <unistd.h> // For execv and fork. |
| #define __STDC_FORMAT_MACROS // PRId64 |
| #include <inttypes.h> |
| |
| #include <set> |
| #include <vector> |
| |
| #include <dbus/dbus-glib-lowlevel.h> |
| #include <glib.h> |
| |
| #include "base/file_util.h" |
| #include "base/logging.h" |
| #include "base/posix/eintr_wrapper.h" |
| #include "base/string_split.h" |
| #include "base/string_util.h" |
| #include "base/stringprintf.h" |
| #include "chromeos/cryptohome.h" |
| #include "chromeos/dbus/dbus.h" |
| #include "chromeos/dbus/service_constants.h" |
| #include "chromeos/process.h" |
| |
| static const char kCollectChromeFile[] = |
| "/mnt/stateful_partition/etc/collect_chrome_crashes"; |
| static const char kCrashTestInProgressPath[] = "/tmp/crash-test-in-progress"; |
| static const char kDefaultLogConfig[] = "/etc/crash_reporter_logs.conf"; |
| static const char kDefaultUserName[] = "chronos"; |
| static const char kLeaveCoreFile[] = "/root/.leave_core"; |
| static const char kLsbRelease[] = "/etc/lsb-release"; |
| static const char kShellPath[] = "/bin/sh"; |
| static const char kSystemCrashPath[] = "/var/spool/crash"; |
| // Normally this path is not used. Unfortunately, there are a few edge cases |
| // where we need this. Any process that runs as kDefaultUserName that crashes |
| // is consider a "user crash". That includes the initial Chrome browser that |
| // runs the login screen. If that blows up, there is no logged in user yet, |
| // so there is no per-user dir for us to stash things in. Instead we fallback |
| // to this path as it is at least encrypted on a per-system basis. |
| // |
| // This also comes up when running autotests. The GUI is sitting at the login |
| // screen while tests are sshing in, changing users, and triggering crashes as |
| // the user (purposefully). |
| static const char kFallbackUserCrashPath[] = "/home/chronos/crash"; |
| |
| // Directory mode of the user crash spool directory. |
| static const mode_t kUserCrashPathMode = 0755; |
| |
| // Directory mode of the system crash spool directory. |
| static const mode_t kSystemCrashPathMode = 01755; |
| |
| static const uid_t kRootOwner = 0; |
| static const uid_t kRootGroup = 0; |
| |
| // Maximum crash reports per crash spool directory. Note that this is |
| // a separate maximum from the maximum rate at which we upload these |
| // diagnostics. The higher this rate is, the more space we allow for |
| // core files, minidumps, and kcrash logs, and equivalently the more |
| // processor and I/O bandwidth we dedicate to handling these crashes when |
| // many occur at once. Also note that if core files are configured to |
| // be left on the file system, we stop adding crashes when either the |
| // number of core files or minidumps reaches this number. |
| const int CrashCollector::kMaxCrashDirectorySize = 32; |
| |
| using base::FilePath; |
| |
| CrashCollector::CrashCollector() |
| : forced_crash_directory_(NULL), |
| lsb_release_(kLsbRelease), |
| log_config_path_(kDefaultLogConfig) { |
| } |
| |
| CrashCollector::~CrashCollector() { |
| } |
| |
| void CrashCollector::Initialize( |
| CrashCollector::CountCrashFunction count_crash_function, |
| CrashCollector::IsFeedbackAllowedFunction is_feedback_allowed_function) { |
| CHECK(count_crash_function != NULL); |
| CHECK(is_feedback_allowed_function != NULL); |
| |
| count_crash_function_ = count_crash_function; |
| is_feedback_allowed_function_ = is_feedback_allowed_function; |
| } |
| |
| int CrashCollector::WriteNewFile(const FilePath &filename, |
| const char *data, |
| int size) { |
| int fd = HANDLE_EINTR(open(filename.value().c_str(), |
| O_CREAT | O_WRONLY | O_TRUNC | O_EXCL, 0666)); |
| if (fd < 0) { |
| return -1; |
| } |
| |
| int rv = file_util::WriteFileDescriptor(fd, data, size); |
| HANDLE_EINTR(close(fd)); |
| return rv; |
| } |
| |
| std::string CrashCollector::Sanitize(const std::string &name) { |
| std::string result = name; |
| for (size_t i = 0; i < name.size(); ++i) { |
| if (!isalnum(result[i]) && result[i] != '_') |
| result[i] = '_'; |
| } |
| return result; |
| } |
| |
| std::string CrashCollector::FormatDumpBasename(const std::string &exec_name, |
| time_t timestamp, |
| pid_t pid) { |
| struct tm tm; |
| localtime_r(×tamp, &tm); |
| std::string sanitized_exec_name = Sanitize(exec_name); |
| return StringPrintf("%s.%04d%02d%02d.%02d%02d%02d.%d", |
| sanitized_exec_name.c_str(), |
| tm.tm_year + 1900, |
| tm.tm_mon + 1, |
| tm.tm_mday, |
| tm.tm_hour, |
| tm.tm_min, |
| tm.tm_sec, |
| pid); |
| } |
| |
| FilePath CrashCollector::GetCrashPath(const FilePath &crash_directory, |
| const std::string &basename, |
| const std::string &extension) { |
| return crash_directory.Append(StringPrintf("%s.%s", |
| basename.c_str(), |
| extension.c_str())); |
| } |
| |
| namespace { |
| |
| const char *GetGErrorMessage(const GError *error) { |
| if (!error) |
| return "Unknown error."; |
| return error->message; |
| } |
| |
| } |
| |
| GHashTable *CrashCollector::GetActiveUserSessions(void) { |
| GHashTable *active_sessions = NULL; |
| |
| chromeos::dbus::BusConnection dbus = chromeos::dbus::GetSystemBusConnection(); |
| if (!dbus.HasConnection()) { |
| LOG(ERROR) << "Error connecting to system D-Bus"; |
| return active_sessions; |
| } |
| chromeos::dbus::Proxy proxy(dbus, |
| login_manager::kSessionManagerServiceName, |
| login_manager::kSessionManagerServicePath, |
| login_manager::kSessionManagerInterface); |
| if (!proxy) { |
| LOG(ERROR) << "Error creating D-Bus proxy to interface " |
| << "'" << login_manager::kSessionManagerServiceName << "'"; |
| return active_sessions; |
| } |
| |
| // Request all the active sessions. |
| GError *gerror = NULL; |
| if (!dbus_g_proxy_call(proxy.gproxy(), |
| login_manager::kSessionManagerRetrieveActiveSessions, |
| &gerror, G_TYPE_INVALID, |
| DBUS_TYPE_G_STRING_STRING_HASHTABLE, &active_sessions, |
| G_TYPE_INVALID)) { |
| LOG(ERROR) << "Error performing D-Bus proxy call " |
| << "'" |
| << login_manager::kSessionManagerRetrieveActiveSessions << "'" |
| << ": " << GetGErrorMessage(gerror); |
| return active_sessions; |
| } |
| |
| return active_sessions; |
| } |
| |
| FilePath CrashCollector::GetUserCrashPath(void) { |
| // In this multiprofile world, there is no one-specific user dir anymore. |
| // Ask the session manager for the active ones, then just run with the |
| // first result we get back. |
| FilePath user_path = FilePath(kFallbackUserCrashPath); |
| GHashTable *active_sessions = GetActiveUserSessions(); |
| if (!active_sessions) |
| return user_path; |
| |
| GList *list = g_hash_table_get_values(active_sessions); |
| if (list) { |
| const char *salted_path = static_cast<const char *>(list->data); |
| user_path = chromeos::cryptohome::home::GetHashedUserPath(salted_path); |
| g_list_free(list); |
| } |
| |
| g_hash_table_destroy(active_sessions); |
| |
| return user_path; |
| } |
| |
| FilePath CrashCollector::GetCrashDirectoryInfo( |
| uid_t process_euid, |
| uid_t default_user_id, |
| gid_t default_user_group, |
| mode_t *mode, |
| uid_t *directory_owner, |
| gid_t *directory_group) { |
| // TODO(mkrebs): This can go away once Chrome crashes are handled |
| // normally (see crosbug.com/5872). |
| // Check if the user crash directory should be used. If we are |
| // collecting chrome crashes during autotesting, we want to put them in |
| // the system crash directory so they are outside the cryptohome -- in |
| // case we are being run during logout (see crosbug.com/18637). |
| if (process_euid == default_user_id && IsUserSpecificDirectoryEnabled()) { |
| *mode = kUserCrashPathMode; |
| *directory_owner = default_user_id; |
| *directory_group = default_user_group; |
| return GetUserCrashPath(); |
| } else { |
| *mode = kSystemCrashPathMode; |
| *directory_owner = kRootOwner; |
| *directory_group = kRootGroup; |
| return FilePath(kSystemCrashPath); |
| } |
| } |
| |
| bool CrashCollector::GetUserInfoFromName(const std::string &name, |
| uid_t *uid, |
| gid_t *gid) { |
| char storage[256]; |
| struct passwd passwd_storage; |
| struct passwd *passwd_result = NULL; |
| |
| if (getpwnam_r(name.c_str(), &passwd_storage, storage, sizeof(storage), |
| &passwd_result) != 0 || passwd_result == NULL) { |
| LOG(ERROR) << "Cannot find user named " << name; |
| return false; |
| } |
| |
| *uid = passwd_result->pw_uid; |
| *gid = passwd_result->pw_gid; |
| return true; |
| } |
| |
| bool CrashCollector::GetCreatedCrashDirectoryByEuid(uid_t euid, |
| FilePath *crash_directory, |
| bool *out_of_capacity) { |
| uid_t default_user_id; |
| gid_t default_user_group; |
| |
| if (out_of_capacity != NULL) *out_of_capacity = false; |
| |
| // For testing. |
| if (forced_crash_directory_ != NULL) { |
| *crash_directory = FilePath(forced_crash_directory_); |
| return true; |
| } |
| |
| if (!GetUserInfoFromName(kDefaultUserName, |
| &default_user_id, |
| &default_user_group)) { |
| LOG(ERROR) << "Could not find default user info"; |
| return false; |
| } |
| mode_t directory_mode; |
| uid_t directory_owner; |
| gid_t directory_group; |
| *crash_directory = |
| GetCrashDirectoryInfo(euid, |
| default_user_id, |
| default_user_group, |
| &directory_mode, |
| &directory_owner, |
| &directory_group); |
| |
| if (!file_util::PathExists(*crash_directory)) { |
| // Create the spool directory with the appropriate mode (regardless of |
| // umask) and ownership. |
| mode_t old_mask = umask(0); |
| if (mkdir(crash_directory->value().c_str(), directory_mode) < 0 || |
| chown(crash_directory->value().c_str(), |
| directory_owner, |
| directory_group) < 0) { |
| LOG(ERROR) << "Unable to create appropriate crash directory"; |
| return false; |
| } |
| umask(old_mask); |
| } |
| |
| if (!file_util::PathExists(*crash_directory)) { |
| LOG(ERROR) << "Unable to create crash directory " |
| << crash_directory->value().c_str(); |
| return false; |
| } |
| |
| if (!CheckHasCapacity(*crash_directory)) { |
| if (out_of_capacity != NULL) *out_of_capacity = true; |
| return false; |
| } |
| |
| return true; |
| } |
| |
| FilePath CrashCollector::GetProcessPath(pid_t pid) { |
| return FilePath(StringPrintf("/proc/%d", pid)); |
| } |
| |
| bool CrashCollector::GetSymlinkTarget(const FilePath &symlink, |
| FilePath *target) { |
| int max_size = 32; |
| scoped_array<char> buffer; |
| while (true) { |
| buffer.reset(new char[max_size + 1]); |
| ssize_t size = readlink(symlink.value().c_str(), buffer.get(), max_size); |
| if (size < 0) { |
| int saved_errno = errno; |
| LOG(ERROR) << "Readlink failed on " << symlink.value() << " with " |
| << saved_errno; |
| return false; |
| } |
| buffer[size] = 0; |
| if (size == max_size) { |
| // Avoid overflow when doubling. |
| if (max_size * 2 > max_size) { |
| max_size *= 2; |
| continue; |
| } else { |
| return false; |
| } |
| } |
| break; |
| } |
| |
| *target = FilePath(buffer.get()); |
| return true; |
| } |
| |
| bool CrashCollector::GetExecutableBaseNameFromPid(pid_t pid, |
| std::string *base_name) { |
| FilePath target; |
| FilePath process_path = GetProcessPath(pid); |
| FilePath exe_path = process_path.Append("exe"); |
| if (!GetSymlinkTarget(exe_path, &target)) { |
| LOG(INFO) << "GetSymlinkTarget failed - Path " << process_path.value() |
| << " DirectoryExists: " |
| << file_util::DirectoryExists(process_path); |
| // Try to further diagnose exe readlink failure cause. |
| struct stat buf; |
| int stat_result = stat(exe_path.value().c_str(), &buf); |
| int saved_errno = errno; |
| if (stat_result < 0) { |
| LOG(INFO) << "stat " << exe_path.value() << " failed: " << stat_result |
| << " " << saved_errno; |
| } else { |
| LOG(INFO) << "stat " << exe_path.value() << " succeeded: st_mode=" |
| << buf.st_mode; |
| } |
| return false; |
| } |
| *base_name = target.BaseName().value(); |
| return true; |
| } |
| |
| // Return true if the given crash directory has not already reached |
| // maximum capacity. |
| bool CrashCollector::CheckHasCapacity(const FilePath &crash_directory) { |
| DIR* dir = opendir(crash_directory.value().c_str()); |
| if (!dir) { |
| return false; |
| } |
| struct dirent ent_buf; |
| struct dirent* ent; |
| bool full = false; |
| std::set<std::string> basenames; |
| while (readdir_r(dir, &ent_buf, &ent) == 0 && ent != NULL) { |
| if ((strcmp(ent->d_name, ".") == 0) || |
| (strcmp(ent->d_name, "..") == 0)) |
| continue; |
| |
| std::string filename(ent->d_name); |
| size_t last_dot = filename.rfind("."); |
| std::string basename; |
| // If there is a valid looking extension, use the base part of the |
| // name. If the only dot is the first byte (aka a dot file), treat |
| // it as unique to avoid allowing a directory full of dot files |
| // from accumulating. |
| if (last_dot != std::string::npos && last_dot != 0) |
| basename = filename.substr(0, last_dot); |
| else |
| basename = filename; |
| basenames.insert(basename); |
| |
| if (basenames.size() >= static_cast<size_t>(kMaxCrashDirectorySize)) { |
| LOG(WARNING) << "Crash directory " << crash_directory.value() |
| << " already full with " << kMaxCrashDirectorySize |
| << " pending reports"; |
| full = true; |
| break; |
| } |
| } |
| closedir(dir); |
| return !full; |
| } |
| |
| bool CrashCollector::IsCommentLine(const std::string &line) { |
| size_t found = line.find_first_not_of(" "); |
| return found != std::string::npos && line[found] == '#'; |
| } |
| |
| bool CrashCollector::ReadKeyValueFile( |
| const FilePath &path, |
| const char separator, |
| std::map<std::string, std::string> *dictionary) { |
| std::string contents; |
| if (!file_util::ReadFileToString(path, &contents)) { |
| return false; |
| } |
| typedef std::vector<std::string> StringVector; |
| StringVector lines; |
| base::SplitString(contents, '\n', &lines); |
| bool any_errors = false; |
| for (StringVector::iterator line = lines.begin(); line != lines.end(); |
| ++line) { |
| // Allow empty strings. |
| if (line->empty()) |
| continue; |
| // Allow comment lines. |
| if (IsCommentLine(*line)) |
| continue; |
| StringVector sides; |
| base::SplitString(*line, separator, &sides); |
| if (sides.size() != 2) { |
| any_errors = true; |
| continue; |
| } |
| dictionary->insert(std::pair<std::string, std::string>(sides[0], sides[1])); |
| } |
| return !any_errors; |
| } |
| |
| bool CrashCollector::GetLogContents(const FilePath &config_path, |
| const std::string &exec_name, |
| const FilePath &output_file) { |
| std::map<std::string, std::string> log_commands; |
| if (!ReadKeyValueFile(config_path, ':', &log_commands)) { |
| LOG(INFO) << "Unable to read log configuration file " |
| << config_path.value(); |
| return false; |
| } |
| |
| if (log_commands.find(exec_name) == log_commands.end()) |
| return false; |
| |
| chromeos::ProcessImpl diag_process; |
| diag_process.AddArg(kShellPath); |
| std::string shell_command = log_commands[exec_name]; |
| diag_process.AddStringOption("-c", shell_command); |
| diag_process.RedirectOutput(output_file.value()); |
| |
| int result = diag_process.Run(); |
| if (result != 0) { |
| LOG(INFO) << "Running shell command " << shell_command << "failed with: " |
| << result; |
| return false; |
| } |
| return true; |
| } |
| |
| void CrashCollector::AddCrashMetaData(const std::string &key, |
| const std::string &value) { |
| extra_metadata_.append(StringPrintf("%s=%s\n", key.c_str(), value.c_str())); |
| } |
| |
| void CrashCollector::WriteCrashMetaData(const FilePath &meta_path, |
| const std::string &exec_name, |
| const std::string &payload_path) { |
| std::map<std::string, std::string> contents; |
| if (!ReadKeyValueFile(FilePath(std::string(lsb_release_)), '=', &contents)) { |
| LOG(ERROR) << "Problem parsing " << lsb_release_; |
| // Even though there was some failure, take as much as we could read. |
| } |
| std::string version("unknown"); |
| std::map<std::string, std::string>::iterator i; |
| if ((i = contents.find("CHROMEOS_RELEASE_VERSION")) != contents.end()) { |
| version = i->second; |
| } |
| int64 payload_size = -1; |
| file_util::GetFileSize(FilePath(payload_path), &payload_size); |
| std::string meta_data = StringPrintf("%sexec_name=%s\n" |
| "ver=%s\n" |
| "payload=%s\n" |
| "payload_size=%"PRId64"\n" |
| "done=1\n", |
| extra_metadata_.c_str(), |
| exec_name.c_str(), |
| version.c_str(), |
| payload_path.c_str(), |
| payload_size); |
| // We must use WriteNewFile instead of file_util::WriteFile as we |
| // do not want to write with root access to a symlink that an attacker |
| // might have created. |
| if (WriteNewFile(meta_path, meta_data.c_str(), meta_data.size()) < 0) { |
| LOG(ERROR) << "Unable to write " << meta_path.value(); |
| } |
| } |
| |
| bool CrashCollector::IsCrashTestInProgress() { |
| return file_util::PathExists(FilePath(kCrashTestInProgressPath)); |
| } |
| |
| bool CrashCollector::IsDeveloperImage() { |
| // If we're testing crash reporter itself, we don't want to special-case |
| // for developer images. |
| if (IsCrashTestInProgress()) |
| return false; |
| return file_util::PathExists(FilePath(kLeaveCoreFile)); |
| } |
| |
| bool CrashCollector::ShouldHandleChromeCrashes() { |
| // If we're testing crash reporter itself, we don't want to allow an |
| // override for chrome crashes. And, let's be conservative and only |
| // allow an override for developer images. |
| if (!IsCrashTestInProgress() && IsDeveloperImage()) { |
| // Check if there's an override to indicate we should indeed collect |
| // chrome crashes. This allows the crashes to still be tracked when |
| // they occur in autotests. See "crosbug.com/17987". |
| if (file_util::PathExists(FilePath(kCollectChromeFile))) |
| return true; |
| } |
| // We default to ignoring chrome crashes. |
| return false; |
| } |
| |
| bool CrashCollector::IsUserSpecificDirectoryEnabled() { |
| return !ShouldHandleChromeCrashes(); |
| } |