/* SPDX-License-Identifier: GPL-2.0-or-later */ /* * Copyright © 2004 Chris Friesen * Copyright © 2009 Canonical Ltd. * Copyright © 2009 Scott James Remnant */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "sd-daemon.h" #include "sd-event.h" #include "alloc-util.h" #include "cgroup-util.h" #include "cpu-set-util.h" #include "dev-setup.h" #include "device-monitor-private.h" #include "device-private.h" #include "device-util.h" #include "event-util.h" #include "fd-util.h" #include "fileio.h" #include "format-util.h" #include "fs-util.h" #include "hashmap.h" #include "inotify-util.h" #include "io-util.h" #include "limits-util.h" #include "list.h" #include "main-func.h" #include "mkdir.h" #include "netlink-util.h" #include "parse-util.h" #include "pretty-print.h" #include "proc-cmdline.h" #include "process-util.h" #include "selinux-util.h" #include "signal-util.h" #include "socket-util.h" #include "string-util.h" #include "strv.h" #include "strxcpyx.h" #include "syslog-util.h" #include "udevd.h" #include "udev-builtin.h" #include "udev-ctrl.h" #include "udev-event.h" #include "udev-util.h" #include "udev-watch.h" #include "user-util.h" #include "version.h" #define WORKER_NUM_MAX 2048U static bool arg_debug = false; static int arg_daemonize = false; static ResolveNameTiming arg_resolve_name_timing = RESOLVE_NAME_EARLY; static unsigned arg_children_max = 0; static usec_t arg_exec_delay_usec = 0; static usec_t arg_event_timeout_usec = 180 * USEC_PER_SEC; static int arg_timeout_signal = SIGKILL; static bool arg_blockdev_read_only = false; typedef struct Event Event; typedef struct Worker Worker; typedef struct Manager { sd_event *event; Hashmap *workers; LIST_HEAD(Event, events); const char *cgroup; pid_t pid; /* the process that originally allocated the manager object */ int log_level; UdevRules *rules; Hashmap *properties; sd_netlink *rtnl; sd_device_monitor *monitor; UdevCtrl *ctrl; int worker_watch[2]; /* used by udev-watch */ int inotify_fd; sd_event_source *inotify_event; sd_event_source *kill_workers_event; usec_t last_usec; bool stop_exec_queue; bool exit; } Manager; typedef enum EventState { EVENT_UNDEF, EVENT_QUEUED, EVENT_RUNNING, } EventState; typedef struct Event { Manager *manager; Worker *worker; EventState state; sd_device *dev; sd_device *dev_kernel; /* clone of originally received device */ uint64_t seqnum; uint64_t blocker_seqnum; sd_event_source *timeout_warning_event; sd_event_source *timeout_event; LIST_FIELDS(Event, event); } Event; typedef enum WorkerState { WORKER_UNDEF, WORKER_RUNNING, WORKER_IDLE, WORKER_KILLED, WORKER_KILLING, } WorkerState; typedef struct Worker { Manager *manager; pid_t pid; sd_device_monitor *monitor; WorkerState state; Event *event; } Worker; /* passed from worker to main process */ typedef struct WorkerMessage { } WorkerMessage; static Event *event_free(Event *event) { if (!event) return NULL; assert(event->manager); LIST_REMOVE(event, event->manager->events, event); sd_device_unref(event->dev); sd_device_unref(event->dev_kernel); sd_event_source_unref(event->timeout_warning_event); sd_event_source_unref(event->timeout_event); if (event->worker) event->worker->event = NULL; /* only clean up the queue from the process that created it */ if (LIST_IS_EMPTY(event->manager->events) && event->manager->pid == getpid_cached()) if (unlink("/run/udev/queue") < 0 && errno != ENOENT) log_warning_errno(errno, "Failed to unlink /run/udev/queue, ignoring: %m"); return mfree(event); } static void event_queue_cleanup(Manager *manager, EventState match_state) { Event *event, *tmp; LIST_FOREACH_SAFE(event, event, tmp, manager->events) { if (match_state != EVENT_UNDEF && match_state != event->state) continue; event_free(event); } } static Worker *worker_free(Worker *worker) { if (!worker) return NULL; assert(worker->manager); hashmap_remove(worker->manager->workers, PID_TO_PTR(worker->pid)); sd_device_monitor_unref(worker->monitor); event_free(worker->event); return mfree(worker); } DEFINE_TRIVIAL_CLEANUP_FUNC(Worker*, worker_free); DEFINE_PRIVATE_HASH_OPS_WITH_VALUE_DESTRUCTOR(worker_hash_op, void, trivial_hash_func, trivial_compare_func, Worker, worker_free); static void manager_clear_for_worker(Manager *manager) { assert(manager); manager->inotify_event = sd_event_source_unref(manager->inotify_event); manager->kill_workers_event = sd_event_source_unref(manager->kill_workers_event); manager->event = sd_event_unref(manager->event); manager->workers = hashmap_free(manager->workers); event_queue_cleanup(manager, EVENT_UNDEF); manager->monitor = sd_device_monitor_unref(manager->monitor); manager->ctrl = udev_ctrl_unref(manager->ctrl); manager->worker_watch[READ_END] = safe_close(manager->worker_watch[READ_END]); } static Manager* manager_free(Manager *manager) { if (!manager) return NULL; udev_builtin_exit(); manager_clear_for_worker(manager); sd_netlink_unref(manager->rtnl); hashmap_free_free_free(manager->properties); udev_rules_free(manager->rules); safe_close(manager->inotify_fd); safe_close_pair(manager->worker_watch); return mfree(manager); } DEFINE_TRIVIAL_CLEANUP_FUNC(Manager*, manager_free); static int worker_new(Worker **ret, Manager *manager, sd_device_monitor *worker_monitor, pid_t pid) { _cleanup_(worker_freep) Worker *worker = NULL; int r; assert(ret); assert(manager); assert(worker_monitor); assert(pid > 1); /* close monitor, but keep address around */ device_monitor_disconnect(worker_monitor); worker = new(Worker, 1); if (!worker) return -ENOMEM; *worker = (Worker) { .manager = manager, .monitor = sd_device_monitor_ref(worker_monitor), .pid = pid, }; r = hashmap_ensure_put(&manager->workers, &worker_hash_op, PID_TO_PTR(pid), worker); if (r < 0) return r; *ret = TAKE_PTR(worker); return 0; } static void manager_kill_workers(Manager *manager, bool force) { Worker *worker; assert(manager); HASHMAP_FOREACH(worker, manager->workers) { if (worker->state == WORKER_KILLED) continue; if (worker->state == WORKER_RUNNING && !force) { worker->state = WORKER_KILLING; continue; } worker->state = WORKER_KILLED; (void) kill(worker->pid, SIGTERM); } } static void manager_exit(Manager *manager) { assert(manager); manager->exit = true; sd_notify(false, "STOPPING=1\n" "STATUS=Starting shutdown..."); /* close sources of new events and discard buffered events */ manager->ctrl = udev_ctrl_unref(manager->ctrl); manager->inotify_event = sd_event_source_unref(manager->inotify_event); manager->inotify_fd = safe_close(manager->inotify_fd); manager->monitor = sd_device_monitor_unref(manager->monitor); /* discard queued events and kill workers */ event_queue_cleanup(manager, EVENT_QUEUED); manager_kill_workers(manager, true); } /* reload requested, HUP signal received, rules changed, builtin changed */ static void manager_reload(Manager *manager) { assert(manager); sd_notify(false, "RELOADING=1\n" "STATUS=Flushing configuration..."); manager_kill_workers(manager, false); manager->rules = udev_rules_free(manager->rules); udev_builtin_exit(); sd_notifyf(false, "READY=1\n" "STATUS=Processing with %u children at max", arg_children_max); } static int on_kill_workers_event(sd_event_source *s, uint64_t usec, void *userdata) { Manager *manager = userdata; assert(manager); log_debug("Cleanup idle workers"); manager_kill_workers(manager, false); return 1; } static int worker_send_message(int fd) { WorkerMessage message = {}; return loop_write(fd, &message, sizeof(message), false); } static int worker_lock_block_device(sd_device *dev, int *ret_fd) { _cleanup_close_ int fd = -1; const char *val; int r; assert(dev); assert(ret_fd); /* Take a shared lock on the device node; this establishes a concept of device "ownership" to * serialize device access. External processes holding an exclusive lock will cause udev to skip the * event handling; in the case udev acquired the lock, the external process can block until udev has * finished its event handling. */ if (device_for_action(dev, SD_DEVICE_REMOVE)) return 0; r = sd_device_get_subsystem(dev, &val); if (r < 0) return log_device_debug_errno(dev, r, "Failed to get subsystem: %m"); if (!streq(val, "block")) return 0; r = sd_device_get_sysname(dev, &val); if (r < 0) return log_device_debug_errno(dev, r, "Failed to get sysname: %m"); if (STARTSWITH_SET(val, "dm-", "md", "drbd")) return 0; r = sd_device_get_devtype(dev, &val); if (r < 0 && r != -ENOENT) return log_device_debug_errno(dev, r, "Failed to get devtype: %m"); if (r >= 0 && streq(val, "partition")) { r = sd_device_get_parent(dev, &dev); if (r < 0) return log_device_debug_errno(dev, r, "Failed to get parent device: %m"); } r = sd_device_get_devname(dev, &val); if (r == -ENOENT) return 0; if (r < 0) return log_device_debug_errno(dev, r, "Failed to get devname: %m"); fd = open(val, O_RDONLY|O_CLOEXEC|O_NOFOLLOW|O_NONBLOCK); if (fd < 0) { log_device_debug_errno(dev, errno, "Failed to open '%s', ignoring: %m", val); return 0; } if (flock(fd, LOCK_SH|LOCK_NB) < 0) return log_device_debug_errno(dev, errno, "Failed to flock(%s): %m", val); *ret_fd = TAKE_FD(fd); return 1; } static int worker_mark_block_device_read_only(sd_device *dev) { _cleanup_close_ int fd = -1; const char *val; int state = 1, r; assert(dev); if (!arg_blockdev_read_only) return 0; /* Do this only once, when the block device is new. If the device is later retriggered let's not * toggle the bit again, so that people can boot up with full read-only mode and then unset the bit * for specific devices only. */ if (!device_for_action(dev, SD_DEVICE_ADD)) return 0; r = sd_device_get_subsystem(dev, &val); if (r < 0) return log_device_debug_errno(dev, r, "Failed to get subsystem: %m"); if (!streq(val, "block")) return 0; r = sd_device_get_sysname(dev, &val); if (r < 0) return log_device_debug_errno(dev, r, "Failed to get sysname: %m"); /* Exclude synthetic devices for now, this is supposed to be a safety feature to avoid modification * of physical devices, and what sits on top of those doesn't really matter if we don't allow the * underlying block devices to receive changes. */ if (STARTSWITH_SET(val, "dm-", "md", "drbd", "loop", "nbd", "zram")) return 0; r = sd_device_get_devname(dev, &val); if (r == -ENOENT) return 0; if (r < 0) return log_device_debug_errno(dev, r, "Failed to get devname: %m"); fd = open(val, O_RDONLY|O_CLOEXEC|O_NOFOLLOW|O_NONBLOCK); if (fd < 0) return log_device_debug_errno(dev, errno, "Failed to open '%s', ignoring: %m", val); if (ioctl(fd, BLKROSET, &state) < 0) return log_device_warning_errno(dev, errno, "Failed to mark block device '%s' read-only: %m", val); log_device_info(dev, "Successfully marked block device '%s' read-only.", val); return 0; } static int worker_process_device(Manager *manager, sd_device *dev) { _cleanup_(udev_event_freep) UdevEvent *udev_event = NULL; _cleanup_close_ int fd_lock = -1; int r; assert(manager); assert(dev); log_device_uevent(dev, "Processing device"); udev_event = udev_event_new(dev, arg_exec_delay_usec, manager->rtnl, manager->log_level); if (!udev_event) return -ENOMEM; r = worker_lock_block_device(dev, &fd_lock); if (r == -EAGAIN) { /* So this is a block device and the device is locked currently via the BSD advisory locks — * someone else is exclusively using it. This means we don't run our udev rules now, to not * interfere. However we want to know when the device is unlocked again, and retrigger the * device again then, so that the rules are run eventually. For that we use IN_CLOSE_WRITE * inotify watches (which isn't exactly the same as waiting for the BSD locks to release, but * not totally off, as long as unlock+close() is done together, as it usually is). * * (The user-facing side of this: https://systemd.io/BLOCK_DEVICE_LOCKING) * * There's a bit of a chicken and egg problem here for this however: inotify watching is * supposed to be enabled via an option set via udev rules (OPTIONS+="watch"). If we skip the * udev rules here however (as we just said we do), we would thus never see that specific * udev rule, and thus never turn on inotify watching. But in order to catch up eventually * and run them we we need the inotify watching: hence a classic chicken and egg problem. * * Our way out here: if we see the block device locked, unconditionally watch the device via * inotify, regardless of any explicit request via OPTIONS+="watch". Thus, a device that is * currently locked via the BSD file locks will be treated as if we ran a single udev rule * only for it: the one that turns on inotify watching for it. If we eventually see the * inotify IN_CLOSE_WRITE event, and then run the rules after all and we then realize that * this wasn't actually requested (i.e. no OPTIONS+="watch" set) we'll simply turn off the * watching again (see below). Effectively this means: inotify watching is now enabled either * a) when the udev rules say so, or b) while the device is locked. * * Worst case scenario hence: in the (unlikely) case someone locked the device and we clash * with that we might do inotify watching for a brief moment for a device where we actually * weren't supposed to. But that shouldn't be too bad, in particular as BSD locks being taken * on a block device is kinda an indication that the inotify logic is desired too, to some * degree — they go hand-in-hand after all. */ log_device_debug(dev, "Block device is currently locked, installing watch to wait until the lock is released."); (void) udev_watch_begin(manager->inotify_fd, dev); /* Now the watch is installed, let's lock the device again, maybe in the meantime things changed */ r = worker_lock_block_device(dev, &fd_lock); } if (r < 0) return r; (void) worker_mark_block_device_read_only(dev); /* apply rules, create node, symlinks */ r = udev_event_execute_rules( udev_event, manager->inotify_fd, arg_event_timeout_usec, arg_timeout_signal, manager->properties, manager->rules); if (r < 0) return r; udev_event_execute_run(udev_event, arg_event_timeout_usec, arg_timeout_signal); if (!manager->rtnl) /* in case rtnl was initialized */ manager->rtnl = sd_netlink_ref(udev_event->rtnl); r = udev_event_process_inotify_watch(udev_event, manager->inotify_fd); if (r < 0) return r; log_device_uevent(dev, "Device processed"); return 0; } static int worker_device_monitor_handler(sd_device_monitor *monitor, sd_device *dev, void *userdata) { Manager *manager = userdata; int r; assert(dev); assert(manager); r = worker_process_device(manager, dev); if (r == -EAGAIN) /* if we couldn't acquire the flock(), then proceed quietly */ log_device_debug_errno(dev, r, "Device currently locked, not processing."); else { if (r < 0) log_device_warning_errno(dev, r, "Failed to process device, ignoring: %m"); /* send processed event back to libudev listeners */ r = device_monitor_send_device(monitor, NULL, dev); if (r < 0) log_device_warning_errno(dev, r, "Failed to send device, ignoring: %m"); } /* send udevd the result of the event execution */ r = worker_send_message(manager->worker_watch[WRITE_END]); if (r < 0) log_device_warning_errno(dev, r, "Failed to send signal to main daemon, ignoring: %m"); /* Reset the log level, as it might be changed by "OPTIONS=log_level=". */ log_set_max_level(manager->log_level); return 1; } static int worker_main(Manager *_manager, sd_device_monitor *monitor, sd_device *first_device) { _cleanup_(sd_device_unrefp) sd_device *dev = first_device; _cleanup_(manager_freep) Manager *manager = _manager; int r; assert(manager); assert(monitor); assert(dev); assert_se(unsetenv("NOTIFY_SOCKET") == 0); assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGTERM, -1) >= 0); /* Reset OOM score, we only protect the main daemon. */ r = set_oom_score_adjust(0); if (r < 0) log_debug_errno(r, "Failed to reset OOM score, ignoring: %m"); /* Clear unnecessary data in Manager object. */ manager_clear_for_worker(manager); r = sd_event_new(&manager->event); if (r < 0) return log_error_errno(r, "Failed to allocate event loop: %m"); r = sd_event_add_signal(manager->event, NULL, SIGTERM, NULL, NULL); if (r < 0) return log_error_errno(r, "Failed to set SIGTERM event: %m"); r = sd_device_monitor_attach_event(monitor, manager->event); if (r < 0) return log_error_errno(r, "Failed to attach event loop to device monitor: %m"); r = sd_device_monitor_start(monitor, worker_device_monitor_handler, manager); if (r < 0) return log_error_errno(r, "Failed to start device monitor: %m"); (void) sd_event_source_set_description(sd_device_monitor_get_event_source(monitor), "worker-device-monitor"); /* Process first device */ (void) worker_device_monitor_handler(monitor, dev, manager); r = sd_event_loop(manager->event); if (r < 0) return log_error_errno(r, "Event loop failed: %m"); return 0; } static int on_event_timeout(sd_event_source *s, uint64_t usec, void *userdata) { Event *event = userdata; assert(event); assert(event->worker); kill_and_sigcont(event->worker->pid, arg_timeout_signal); event->worker->state = WORKER_KILLED; log_device_error(event->dev, "Worker ["PID_FMT"] processing SEQNUM=%"PRIu64" killed", event->worker->pid, event->seqnum); return 1; } static int on_event_timeout_warning(sd_event_source *s, uint64_t usec, void *userdata) { Event *event = userdata; assert(event); assert(event->worker); log_device_warning(event->dev, "Worker ["PID_FMT"] processing SEQNUM=%"PRIu64" is taking a long time", event->worker->pid, event->seqnum); return 1; } static void worker_attach_event(Worker *worker, Event *event) { sd_event *e; assert(worker); assert(worker->manager); assert(event); assert(!event->worker); assert(!worker->event); worker->state = WORKER_RUNNING; worker->event = event; event->state = EVENT_RUNNING; event->worker = worker; e = worker->manager->event; (void) sd_event_add_time_relative(e, &event->timeout_warning_event, CLOCK_MONOTONIC, udev_warn_timeout(arg_event_timeout_usec), USEC_PER_SEC, on_event_timeout_warning, event); (void) sd_event_add_time_relative(e, &event->timeout_event, CLOCK_MONOTONIC, arg_event_timeout_usec, USEC_PER_SEC, on_event_timeout, event); } static int worker_spawn(Manager *manager, Event *event) { _cleanup_(sd_device_monitor_unrefp) sd_device_monitor *worker_monitor = NULL; Worker *worker; pid_t pid; int r; /* listen for new events */ r = device_monitor_new_full(&worker_monitor, MONITOR_GROUP_NONE, -1); if (r < 0) return r; /* allow the main daemon netlink address to send devices to the worker */ r = device_monitor_allow_unicast_sender(worker_monitor, manager->monitor); if (r < 0) return log_error_errno(r, "Worker: Failed to set unicast sender: %m"); r = device_monitor_enable_receiving(worker_monitor); if (r < 0) return log_error_errno(r, "Worker: Failed to enable receiving of device: %m"); r = safe_fork(NULL, FORK_DEATHSIG, &pid); if (r < 0) { event->state = EVENT_QUEUED; return log_error_errno(r, "Failed to fork() worker: %m"); } if (r == 0) { DEVICE_TRACE_POINT(worker_spawned, event->dev, getpid()); /* Worker process */ r = worker_main(manager, worker_monitor, sd_device_ref(event->dev)); log_close(); _exit(r < 0 ? EXIT_FAILURE : EXIT_SUCCESS); } r = worker_new(&worker, manager, worker_monitor, pid); if (r < 0) return log_error_errno(r, "Failed to create worker object: %m"); worker_attach_event(worker, event); log_device_debug(event->dev, "Worker ["PID_FMT"] is forked for processing SEQNUM=%"PRIu64".", pid, event->seqnum); return 0; } static int event_run(Event *event) { static bool log_children_max_reached = true; Manager *manager; Worker *worker; int r; assert(event); assert(event->manager); log_device_uevent(event->dev, "Device ready for processing"); manager = event->manager; HASHMAP_FOREACH(worker, manager->workers) { if (worker->state != WORKER_IDLE) continue; r = device_monitor_send_device(manager->monitor, worker->monitor, event->dev); if (r < 0) { log_device_error_errno(event->dev, r, "Worker ["PID_FMT"] did not accept message, killing the worker: %m", worker->pid); (void) kill(worker->pid, SIGKILL); worker->state = WORKER_KILLED; continue; } worker_attach_event(worker, event); return 1; /* event is now processing. */ } if (hashmap_size(manager->workers) >= arg_children_max) { /* Avoid spamming the debug logs if the limit is already reached and * many events still need to be processed */ if (log_children_max_reached && arg_children_max > 1) { log_debug("Maximum number (%u) of children reached.", hashmap_size(manager->workers)); log_children_max_reached = false; } return 0; /* no free worker */ } /* Re-enable the debug message for the next batch of events */ log_children_max_reached = true; /* fork with up-to-date SELinux label database, so the child inherits the up-to-date db * and, until the next SELinux policy changes, we safe further reloads in future children */ mac_selinux_maybe_reload(); /* start new worker and pass initial device */ r = worker_spawn(manager, event); if (r < 0) return r; return 1; /* event is now processing. */ } static int event_is_blocked(Event *event) { const char *subsystem, *devpath, *devpath_old = NULL; dev_t devnum = makedev(0, 0); Event *loop_event; size_t devpath_len; int r, ifindex = 0; bool is_block; /* lookup event for identical, parent, child device */ assert(event); assert(event->manager); assert(event->blocker_seqnum <= event->seqnum); if (event->blocker_seqnum == event->seqnum) /* we have checked previously and no blocker found */ return false; LIST_FOREACH(event, loop_event, event->manager->events) { /* we already found a later event, earlier cannot block us, no need to check again */ if (loop_event->seqnum < event->blocker_seqnum) continue; /* event we checked earlier still exists, no need to check again */ if (loop_event->seqnum == event->blocker_seqnum) return true; /* found ourself, no later event can block us */ if (loop_event->seqnum >= event->seqnum) goto no_blocker; /* found event we have not checked */ break; } assert(loop_event); assert(loop_event->seqnum > event->blocker_seqnum && loop_event->seqnum < event->seqnum); r = sd_device_get_subsystem(event->dev, &subsystem); if (r < 0) return r; is_block = streq(subsystem, "block"); r = sd_device_get_devpath(event->dev, &devpath); if (r < 0) return r; devpath_len = strlen(devpath); r = sd_device_get_property_value(event->dev, "DEVPATH_OLD", &devpath_old); if (r < 0 && r != -ENOENT) return r; r = sd_device_get_devnum(event->dev, &devnum); if (r < 0 && r != -ENOENT) return r; r = sd_device_get_ifindex(event->dev, &ifindex); if (r < 0 && r != -ENOENT) return r; /* check if queue contains events we depend on */ LIST_FOREACH(event, loop_event, loop_event) { size_t loop_devpath_len, common; const char *loop_devpath; /* found ourself, no later event can block us */ if (loop_event->seqnum >= event->seqnum) goto no_blocker; /* check major/minor */ if (major(devnum) != 0) { const char *s; dev_t d; if (sd_device_get_subsystem(loop_event->dev, &s) < 0) continue; if (sd_device_get_devnum(loop_event->dev, &d) >= 0 && devnum == d && is_block == streq(s, "block")) break; } /* check network device ifindex */ if (ifindex > 0) { int i; if (sd_device_get_ifindex(loop_event->dev, &i) >= 0 && ifindex == i) break; } if (sd_device_get_devpath(loop_event->dev, &loop_devpath) < 0) continue; /* check our old name */ if (devpath_old && streq(devpath_old, loop_devpath)) break; loop_devpath_len = strlen(loop_devpath); /* compare devpath */ common = MIN(devpath_len, loop_devpath_len); /* one devpath is contained in the other? */ if (!strneq(devpath, loop_devpath, common)) continue; /* identical device event found */ if (devpath_len == loop_devpath_len) break; /* parent device event found */ if (devpath[common] == '/') break; /* child device event found */ if (loop_devpath[common] == '/') break; } assert(loop_event); log_device_debug(event->dev, "SEQNUM=%" PRIu64 " blocked by SEQNUM=%" PRIu64, event->seqnum, loop_event->seqnum); event->blocker_seqnum = loop_event->seqnum; return true; no_blocker: event->blocker_seqnum = event->seqnum; return false; } static int event_queue_start(Manager *manager) { Event *event, *event_next; usec_t usec; int r; assert(manager); if (LIST_IS_EMPTY(manager->events) || manager->exit || manager->stop_exec_queue) return 0; assert_se(sd_event_now(manager->event, CLOCK_MONOTONIC, &usec) >= 0); /* check for changed config, every 3 seconds at most */ if (manager->last_usec == 0 || usec > usec_add(manager->last_usec, 3 * USEC_PER_SEC)) { if (udev_rules_check_timestamp(manager->rules) || udev_builtin_validate()) manager_reload(manager); manager->last_usec = usec; } r = event_source_disable(manager->kill_workers_event); if (r < 0) log_warning_errno(r, "Failed to disable event source for cleaning up idle workers, ignoring: %m"); udev_builtin_init(); if (!manager->rules) { r = udev_rules_load(&manager->rules, arg_resolve_name_timing); if (r < 0) return log_warning_errno(r, "Failed to read udev rules: %m"); } LIST_FOREACH_SAFE(event, event, event_next, manager->events) { if (event->state != EVENT_QUEUED) continue; /* do not start event if parent or child event is still running or queued */ r = event_is_blocked(event); if (r < 0) { sd_device_action_t a = _SD_DEVICE_ACTION_INVALID; (void) sd_device_get_action(event->dev, &a); log_device_warning_errno(event->dev, r, "Failed to check event dependency, " "skipping event (SEQNUM=%"PRIu64", ACTION=%s)", event->seqnum, strna(device_action_to_string(a))); event_free(event); return r; } if (r > 0) continue; r = event_run(event); if (r <= 0) return r; } return 0; } static int event_queue_insert(Manager *manager, sd_device *dev) { _cleanup_(sd_device_unrefp) sd_device *clone = NULL; Event *event; uint64_t seqnum; int r; assert(manager); assert(dev); /* only one process can add events to the queue */ assert(manager->pid == getpid_cached()); /* We only accepts devices received by device monitor. */ r = sd_device_get_seqnum(dev, &seqnum); if (r < 0) return r; /* Save original device to restore the state on failures. */ r = device_shallow_clone(dev, &clone); if (r < 0) return r; r = device_copy_properties(clone, dev); if (r < 0) return r; event = new(Event, 1); if (!event) return -ENOMEM; *event = (Event) { .manager = manager, .dev = sd_device_ref(dev), .dev_kernel = TAKE_PTR(clone), .seqnum = seqnum, .state = EVENT_QUEUED, }; if (LIST_IS_EMPTY(manager->events)) { r = touch("/run/udev/queue"); if (r < 0) log_warning_errno(r, "Failed to touch /run/udev/queue, ignoring: %m"); } LIST_APPEND(event, manager->events, event); log_device_uevent(dev, "Device is queued"); return 0; } static int on_uevent(sd_device_monitor *monitor, sd_device *dev, void *userdata) { Manager *manager = userdata; int r; assert(manager); DEVICE_TRACE_POINT(kernel_uevent_received, dev); device_ensure_usec_initialized(dev, NULL); r = event_queue_insert(manager, dev); if (r < 0) { log_device_error_errno(dev, r, "Failed to insert device into event queue: %m"); return 1; } /* we have fresh events, try to schedule them */ event_queue_start(manager); return 1; } static int on_worker(sd_event_source *s, int fd, uint32_t revents, void *userdata) { Manager *manager = userdata; assert(manager); for (;;) { WorkerMessage msg; struct iovec iovec = { .iov_base = &msg, .iov_len = sizeof(msg), }; CMSG_BUFFER_TYPE(CMSG_SPACE(sizeof(struct ucred))) control; struct msghdr msghdr = { .msg_iov = &iovec, .msg_iovlen = 1, .msg_control = &control, .msg_controllen = sizeof(control), }; ssize_t size; struct ucred *ucred; Worker *worker; size = recvmsg_safe(fd, &msghdr, MSG_DONTWAIT); if (size == -EINTR) continue; if (size == -EAGAIN) /* nothing more to read */ break; if (size < 0) return log_error_errno(size, "Failed to receive message: %m"); cmsg_close_all(&msghdr); if (size != sizeof(WorkerMessage)) { log_warning("Ignoring worker message with invalid size %zi bytes", size); continue; } ucred = CMSG_FIND_DATA(&msghdr, SOL_SOCKET, SCM_CREDENTIALS, struct ucred); if (!ucred || ucred->pid <= 0) { log_warning("Ignoring worker message without valid PID"); continue; } /* lookup worker who sent the signal */ worker = hashmap_get(manager->workers, PID_TO_PTR(ucred->pid)); if (!worker) { log_debug("Worker ["PID_FMT"] returned, but is no longer tracked", ucred->pid); continue; } if (worker->state == WORKER_KILLING) { worker->state = WORKER_KILLED; (void) kill(worker->pid, SIGTERM); } else if (worker->state != WORKER_KILLED) worker->state = WORKER_IDLE; /* worker returned */ event_free(worker->event); } /* we have free workers, try to schedule events */ event_queue_start(manager); return 1; } /* receive the udevd message from userspace */ static int on_ctrl_msg(UdevCtrl *uctrl, UdevCtrlMessageType type, const UdevCtrlMessageValue *value, void *userdata) { Manager *manager = userdata; int r; assert(value); assert(manager); switch (type) { case UDEV_CTRL_SET_LOG_LEVEL: log_debug("Received udev control message (SET_LOG_LEVEL), setting log_level=%i", value->intval); log_set_max_level(value->intval); manager->log_level = value->intval; manager_kill_workers(manager, false); break; case UDEV_CTRL_STOP_EXEC_QUEUE: log_debug("Received udev control message (STOP_EXEC_QUEUE)"); manager->stop_exec_queue = true; break; case UDEV_CTRL_START_EXEC_QUEUE: log_debug("Received udev control message (START_EXEC_QUEUE)"); manager->stop_exec_queue = false; event_queue_start(manager); break; case UDEV_CTRL_RELOAD: log_debug("Received udev control message (RELOAD)"); manager_reload(manager); break; case UDEV_CTRL_SET_ENV: { _unused_ _cleanup_free_ char *old_val = NULL; _cleanup_free_ char *key = NULL, *val = NULL, *old_key = NULL; const char *eq; eq = strchr(value->buf, '='); if (!eq) { log_error("Invalid key format '%s'", value->buf); return 1; } key = strndup(value->buf, eq - value->buf); if (!key) { log_oom(); return 1; } old_val = hashmap_remove2(manager->properties, key, (void **) &old_key); r = hashmap_ensure_allocated(&manager->properties, &string_hash_ops); if (r < 0) { log_oom(); return 1; } eq++; if (isempty(eq)) { log_debug("Received udev control message (ENV), unsetting '%s'", key); r = hashmap_put(manager->properties, key, NULL); if (r < 0) { log_oom(); return 1; } } else { val = strdup(eq); if (!val) { log_oom(); return 1; } log_debug("Received udev control message (ENV), setting '%s=%s'", key, val); r = hashmap_put(manager->properties, key, val); if (r < 0) { log_oom(); return 1; } } key = val = NULL; manager_kill_workers(manager, false); break; } case UDEV_CTRL_SET_CHILDREN_MAX: if (value->intval <= 0) { log_debug("Received invalid udev control message (SET_MAX_CHILDREN, %i), ignoring.", value->intval); return 0; } log_debug("Received udev control message (SET_MAX_CHILDREN), setting children_max=%i", value->intval); arg_children_max = value->intval; (void) sd_notifyf(false, "READY=1\n" "STATUS=Processing with %u children at max", arg_children_max); break; case UDEV_CTRL_PING: log_debug("Received udev control message (PING)"); break; case UDEV_CTRL_EXIT: log_debug("Received udev control message (EXIT)"); manager_exit(manager); break; default: log_debug("Received unknown udev control message, ignoring"); } return 1; } static int synthesize_change_one(sd_device *dev, sd_device *target) { int r; if (DEBUG_LOGGING) { const char *syspath = NULL; (void) sd_device_get_syspath(target, &syspath); log_device_debug(dev, "device is closed, synthesising 'change' on %s", strna(syspath)); } r = sd_device_trigger(target, SD_DEVICE_CHANGE); if (r < 0) return log_device_debug_errno(target, r, "Failed to trigger 'change' uevent: %m"); DEVICE_TRACE_POINT(synthetic_change_event, dev); return 0; } static int synthesize_change(sd_device *dev) { const char *subsystem, *sysname, *devtype; int r; r = sd_device_get_subsystem(dev, &subsystem); if (r < 0) return r; r = sd_device_get_devtype(dev, &devtype); if (r < 0) return r; r = sd_device_get_sysname(dev, &sysname); if (r < 0) return r; if (streq_ptr(subsystem, "block") && streq_ptr(devtype, "disk") && !startswith(sysname, "dm-")) { _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL; bool part_table_read = false, has_partitions = false; const char *devname; sd_device *d; int fd; r = sd_device_get_devname(dev, &devname); if (r < 0) return r; /* Try to re-read the partition table. This only succeeds if none of the devices is * busy. The kernel returns 0 if no partition table is found, and we will not get an * event for the disk. */ fd = open(devname, O_RDONLY|O_CLOEXEC|O_NOFOLLOW|O_NONBLOCK); if (fd >= 0) { r = flock(fd, LOCK_EX|LOCK_NB); if (r >= 0) r = ioctl(fd, BLKRRPART, 0); close(fd); if (r >= 0) part_table_read = true; } /* search for partitions */ r = sd_device_enumerator_new(&e); if (r < 0) return r; r = sd_device_enumerator_allow_uninitialized(e); if (r < 0) return r; r = sd_device_enumerator_add_match_parent(e, dev); if (r < 0) return r; r = sd_device_enumerator_add_match_subsystem(e, "block", true); if (r < 0) return r; FOREACH_DEVICE(e, d) { const char *t; if (sd_device_get_devtype(d, &t) < 0 || !streq(t, "partition")) continue; has_partitions = true; break; } /* We have partitions and re-read the table, the kernel already sent out a "change" * event for the disk, and "remove/add" for all partitions. */ if (part_table_read && has_partitions) return 0; /* We have partitions but re-reading the partition table did not work, synthesize * "change" for the disk and all partitions. */ (void) synthesize_change_one(dev, dev); FOREACH_DEVICE(e, d) { const char *t; if (sd_device_get_devtype(d, &t) < 0 || !streq(t, "partition")) continue; (void) synthesize_change_one(dev, d); } } else (void) synthesize_change_one(dev, dev); return 0; } static int on_inotify(sd_event_source *s, int fd, uint32_t revents, void *userdata) { Manager *manager = userdata; union inotify_event_buffer buffer; struct inotify_event *e; ssize_t l; int r; assert(manager); r = event_source_disable(manager->kill_workers_event); if (r < 0) log_warning_errno(r, "Failed to disable event source for cleaning up idle workers, ignoring: %m"); l = read(fd, &buffer, sizeof(buffer)); if (l < 0) { if (IN_SET(errno, EAGAIN, EINTR)) return 1; return log_error_errno(errno, "Failed to read inotify fd: %m"); } FOREACH_INOTIFY_EVENT(e, buffer, l) { _cleanup_(sd_device_unrefp) sd_device *dev = NULL; const char *devnode; r = device_new_from_watch_handle(&dev, e->wd); if (r < 0) { log_debug_errno(r, "Failed to create sd_device object from watch handle, ignoring: %m"); continue; } if (sd_device_get_devname(dev, &devnode) < 0) continue; log_device_debug(dev, "Inotify event: %x for %s", e->mask, devnode); if (e->mask & IN_CLOSE_WRITE) (void) synthesize_change(dev); /* Do not handle IN_IGNORED here. It should be handled by worker in 'remove' uevent; * udev_event_execute_rules() -> event_execute_rules_on_remove() -> udev_watch_end(). */ } return 1; } static int on_sigterm(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) { Manager *manager = userdata; assert(manager); manager_exit(manager); return 1; } static int on_sighup(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) { Manager *manager = userdata; assert(manager); manager_reload(manager); return 1; } static int on_sigchld(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) { Manager *manager = userdata; int r; assert(manager); for (;;) { pid_t pid; int status; Worker *worker; pid = waitpid(-1, &status, WNOHANG); if (pid <= 0) break; worker = hashmap_get(manager->workers, PID_TO_PTR(pid)); if (!worker) { log_warning("Worker ["PID_FMT"] is unknown, ignoring", pid); continue; } if (WIFEXITED(status)) { if (WEXITSTATUS(status) == 0) log_debug("Worker ["PID_FMT"] exited", pid); else log_warning("Worker ["PID_FMT"] exited with return code %i", pid, WEXITSTATUS(status)); } else if (WIFSIGNALED(status)) log_warning("Worker ["PID_FMT"] terminated by signal %i (%s)", pid, WTERMSIG(status), signal_to_string(WTERMSIG(status))); else if (WIFSTOPPED(status)) { log_info("Worker ["PID_FMT"] stopped", pid); continue; } else if (WIFCONTINUED(status)) { log_info("Worker ["PID_FMT"] continued", pid); continue; } else log_warning("Worker ["PID_FMT"] exit with status 0x%04x", pid, status); if ((!WIFEXITED(status) || WEXITSTATUS(status) != 0) && worker->event) { log_device_error(worker->event->dev, "Worker ["PID_FMT"] failed", pid); /* delete state from disk */ device_delete_db(worker->event->dev); device_tag_index(worker->event->dev, NULL, false); if (manager->monitor) { /* forward kernel event without amending it */ r = device_monitor_send_device(manager->monitor, NULL, worker->event->dev_kernel); if (r < 0) log_device_error_errno(worker->event->dev_kernel, r, "Failed to send back device to kernel: %m"); } } worker_free(worker); } /* we can start new workers, try to schedule events */ event_queue_start(manager); /* Disable unnecessary cleanup event */ if (hashmap_isempty(manager->workers)) { r = event_source_disable(manager->kill_workers_event); if (r < 0) log_warning_errno(r, "Failed to disable event source for cleaning up idle workers, ignoring: %m"); } return 1; } static int on_post(sd_event_source *s, void *userdata) { Manager *manager = userdata; assert(manager); if (!LIST_IS_EMPTY(manager->events)) return 1; /* There are no pending events. Let's cleanup idle process. */ if (!hashmap_isempty(manager->workers)) { /* There are idle workers */ (void) event_reset_time(manager->event, &manager->kill_workers_event, CLOCK_MONOTONIC, now(CLOCK_MONOTONIC) + 3 * USEC_PER_SEC, USEC_PER_SEC, on_kill_workers_event, manager, 0, "kill-workers-event", false); return 1; } /* There are no idle workers. */ if (manager->exit) return sd_event_exit(manager->event, 0); if (manager->cgroup) /* cleanup possible left-over processes in our cgroup */ (void) cg_kill(SYSTEMD_CGROUP_CONTROLLER, manager->cgroup, SIGKILL, CGROUP_IGNORE_SELF, NULL, NULL, NULL); return 1; } static int listen_fds(int *ret_ctrl, int *ret_netlink) { int ctrl_fd = -1, netlink_fd = -1; int fd, n; assert(ret_ctrl); assert(ret_netlink); n = sd_listen_fds(true); if (n < 0) return n; for (fd = SD_LISTEN_FDS_START; fd < n + SD_LISTEN_FDS_START; fd++) { if (sd_is_socket(fd, AF_LOCAL, SOCK_SEQPACKET, -1) > 0) { if (ctrl_fd >= 0) return -EINVAL; ctrl_fd = fd; continue; } if (sd_is_socket(fd, AF_NETLINK, SOCK_RAW, -1) > 0) { if (netlink_fd >= 0) return -EINVAL; netlink_fd = fd; continue; } return -EINVAL; } *ret_ctrl = ctrl_fd; *ret_netlink = netlink_fd; return 0; } /* * read the kernel command line, in case we need to get into debug mode * udev.log_level= syslog priority * udev.children_max= events are fully serialized if set to 1 * udev.exec_delay= delay execution of every executed program * udev.event_timeout= seconds to wait before terminating an event * udev.blockdev_read_only<=bool> mark all block devices read-only when they appear */ static int parse_proc_cmdline_item(const char *key, const char *value, void *data) { int r; assert(key); if (proc_cmdline_key_streq(key, "udev.log_level") || proc_cmdline_key_streq(key, "udev.log_priority")) { /* kept for backward compatibility */ if (proc_cmdline_value_missing(key, value)) return 0; r = log_level_from_string(value); if (r >= 0) log_set_max_level(r); } else if (proc_cmdline_key_streq(key, "udev.event_timeout")) { if (proc_cmdline_value_missing(key, value)) return 0; r = parse_sec(value, &arg_event_timeout_usec); } else if (proc_cmdline_key_streq(key, "udev.children_max")) { if (proc_cmdline_value_missing(key, value)) return 0; r = safe_atou(value, &arg_children_max); } else if (proc_cmdline_key_streq(key, "udev.exec_delay")) { if (proc_cmdline_value_missing(key, value)) return 0; r = parse_sec(value, &arg_exec_delay_usec); } else if (proc_cmdline_key_streq(key, "udev.timeout_signal")) { if (proc_cmdline_value_missing(key, value)) return 0; r = signal_from_string(value); if (r > 0) arg_timeout_signal = r; } else if (proc_cmdline_key_streq(key, "udev.blockdev_read_only")) { if (!value) arg_blockdev_read_only = true; else { r = parse_boolean(value); if (r < 0) log_warning_errno(r, "Failed to parse udev.blockdev-read-only argument, ignoring: %s", value); else arg_blockdev_read_only = r; } if (arg_blockdev_read_only) log_notice("All physical block devices will be marked read-only."); return 0; } else { if (startswith(key, "udev.")) log_warning("Unknown udev kernel command line option \"%s\", ignoring.", key); return 0; } if (r < 0) log_warning_errno(r, "Failed to parse \"%s=%s\", ignoring: %m", key, value); return 0; } static int help(void) { _cleanup_free_ char *link = NULL; int r; r = terminal_urlify_man("systemd-udevd.service", "8", &link); if (r < 0) return log_oom(); printf("%s [OPTIONS...]\n\n" "Rule-based manager for device events and files.\n\n" " -h --help Print this message\n" " -V --version Print version of the program\n" " -d --daemon Detach and run in the background\n" " -D --debug Enable debug output\n" " -c --children-max=INT Set maximum number of workers\n" " -e --exec-delay=SECONDS Seconds to wait before executing RUN=\n" " -t --event-timeout=SECONDS Seconds to wait before terminating an event\n" " -N --resolve-names=early|late|never\n" " When to resolve users and groups\n" "\nSee the %s for details.\n", program_invocation_short_name, link); return 0; } static int parse_argv(int argc, char *argv[]) { enum { ARG_TIMEOUT_SIGNAL, }; static const struct option options[] = { { "daemon", no_argument, NULL, 'd' }, { "debug", no_argument, NULL, 'D' }, { "children-max", required_argument, NULL, 'c' }, { "exec-delay", required_argument, NULL, 'e' }, { "event-timeout", required_argument, NULL, 't' }, { "resolve-names", required_argument, NULL, 'N' }, { "help", no_argument, NULL, 'h' }, { "version", no_argument, NULL, 'V' }, { "timeout-signal", required_argument, NULL, ARG_TIMEOUT_SIGNAL }, {} }; int c, r; assert(argc >= 0); assert(argv); while ((c = getopt_long(argc, argv, "c:de:Dt:N:hV", options, NULL)) >= 0) { switch (c) { case 'd': arg_daemonize = true; break; case 'c': r = safe_atou(optarg, &arg_children_max); if (r < 0) log_warning_errno(r, "Failed to parse --children-max= value '%s', ignoring: %m", optarg); break; case 'e': r = parse_sec(optarg, &arg_exec_delay_usec); if (r < 0) log_warning_errno(r, "Failed to parse --exec-delay= value '%s', ignoring: %m", optarg); break; case ARG_TIMEOUT_SIGNAL: r = signal_from_string(optarg); if (r <= 0) log_warning_errno(r, "Failed to parse --timeout-signal= value '%s', ignoring: %m", optarg); else arg_timeout_signal = r; break; case 't': r = parse_sec(optarg, &arg_event_timeout_usec); if (r < 0) log_warning_errno(r, "Failed to parse --event-timeout= value '%s', ignoring: %m", optarg); break; case 'D': arg_debug = true; break; case 'N': { ResolveNameTiming t; t = resolve_name_timing_from_string(optarg); if (t < 0) log_warning("Invalid --resolve-names= value '%s', ignoring.", optarg); else arg_resolve_name_timing = t; break; } case 'h': return help(); case 'V': printf("%s\n", GIT_VERSION); return 0; case '?': return -EINVAL; default: assert_not_reached(); } } return 1; } static int manager_new(Manager **ret, int fd_ctrl, int fd_uevent, const char *cgroup) { _cleanup_(manager_freep) Manager *manager = NULL; int r; assert(ret); manager = new(Manager, 1); if (!manager) return log_oom(); *manager = (Manager) { .inotify_fd = -1, .worker_watch = { -1, -1 }, .cgroup = cgroup, }; r = udev_ctrl_new_from_fd(&manager->ctrl, fd_ctrl); if (r < 0) return log_error_errno(r, "Failed to initialize udev control socket: %m"); r = udev_ctrl_enable_receiving(manager->ctrl); if (r < 0) return log_error_errno(r, "Failed to bind udev control socket: %m"); r = device_monitor_new_full(&manager->monitor, MONITOR_GROUP_KERNEL, fd_uevent); if (r < 0) return log_error_errno(r, "Failed to initialize device monitor: %m"); /* Bump receiver buffer, but only if we are not called via socket activation, as in that * case systemd sets the receive buffer size for us, and the value in the .socket unit * should take full effect. */ if (fd_uevent < 0) { r = sd_device_monitor_set_receive_buffer_size(manager->monitor, 128 * 1024 * 1024); if (r < 0) log_warning_errno(r, "Failed to set receive buffer size for device monitor, ignoring: %m"); } r = device_monitor_enable_receiving(manager->monitor); if (r < 0) return log_error_errno(r, "Failed to bind netlink socket: %m"); manager->log_level = log_get_max_level(); *ret = TAKE_PTR(manager); return 0; } static int main_loop(Manager *manager) { int fd_worker, r; manager->pid = getpid_cached(); /* unnamed socket from workers to the main daemon */ r = socketpair(AF_LOCAL, SOCK_DGRAM|SOCK_CLOEXEC, 0, manager->worker_watch); if (r < 0) return log_error_errno(errno, "Failed to create socketpair for communicating with workers: %m"); fd_worker = manager->worker_watch[READ_END]; r = setsockopt_int(fd_worker, SOL_SOCKET, SO_PASSCRED, true); if (r < 0) return log_error_errno(r, "Failed to enable SO_PASSCRED: %m"); manager->inotify_fd = inotify_init1(IN_CLOEXEC); if (manager->inotify_fd < 0) return log_error_errno(errno, "Failed to create inotify descriptor: %m"); udev_watch_restore(manager->inotify_fd); /* block and listen to all signals on signalfd */ assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGTERM, SIGINT, SIGHUP, SIGCHLD, -1) >= 0); r = sd_event_default(&manager->event); if (r < 0) return log_error_errno(r, "Failed to allocate event loop: %m"); r = sd_event_add_signal(manager->event, NULL, SIGINT, on_sigterm, manager); if (r < 0) return log_error_errno(r, "Failed to create SIGINT event source: %m"); r = sd_event_add_signal(manager->event, NULL, SIGTERM, on_sigterm, manager); if (r < 0) return log_error_errno(r, "Failed to create SIGTERM event source: %m"); r = sd_event_add_signal(manager->event, NULL, SIGHUP, on_sighup, manager); if (r < 0) return log_error_errno(r, "Failed to create SIGHUP event source: %m"); r = sd_event_add_signal(manager->event, NULL, SIGCHLD, on_sigchld, manager); if (r < 0) return log_error_errno(r, "Failed to create SIGCHLD event source: %m"); r = sd_event_set_watchdog(manager->event, true); if (r < 0) return log_error_errno(r, "Failed to create watchdog event source: %m"); r = udev_ctrl_attach_event(manager->ctrl, manager->event); if (r < 0) return log_error_errno(r, "Failed to attach event to udev control: %m"); r = udev_ctrl_start(manager->ctrl, on_ctrl_msg, manager); if (r < 0) return log_error_errno(r, "Failed to start device monitor: %m"); /* This needs to be after the inotify and uevent handling, to make sure * that the ping is send back after fully processing the pending uevents * (including the synthetic ones we may create due to inotify events). */ r = sd_event_source_set_priority(udev_ctrl_get_event_source(manager->ctrl), SD_EVENT_PRIORITY_IDLE); if (r < 0) return log_error_errno(r, "Failed to set IDLE event priority for udev control event source: %m"); r = sd_event_add_io(manager->event, &manager->inotify_event, manager->inotify_fd, EPOLLIN, on_inotify, manager); if (r < 0) return log_error_errno(r, "Failed to create inotify event source: %m"); r = sd_device_monitor_attach_event(manager->monitor, manager->event); if (r < 0) return log_error_errno(r, "Failed to attach event to device monitor: %m"); r = sd_device_monitor_start(manager->monitor, on_uevent, manager); if (r < 0) return log_error_errno(r, "Failed to start device monitor: %m"); (void) sd_event_source_set_description(sd_device_monitor_get_event_source(manager->monitor), "device-monitor"); r = sd_event_add_io(manager->event, NULL, fd_worker, EPOLLIN, on_worker, manager); if (r < 0) return log_error_errno(r, "Failed to create worker event source: %m"); r = sd_event_add_post(manager->event, NULL, on_post, manager); if (r < 0) return log_error_errno(r, "Failed to create post event source: %m"); udev_builtin_init(); r = udev_rules_load(&manager->rules, arg_resolve_name_timing); if (!manager->rules) return log_error_errno(r, "Failed to read udev rules: %m"); r = udev_rules_apply_static_dev_perms(manager->rules); if (r < 0) log_error_errno(r, "Failed to apply permissions on static device nodes: %m"); (void) sd_notifyf(false, "READY=1\n" "STATUS=Processing with %u children at max", arg_children_max); r = sd_event_loop(manager->event); if (r < 0) log_error_errno(r, "Event loop failed: %m"); sd_notify(false, "STOPPING=1\n" "STATUS=Shutting down..."); return r; } int run_udevd(int argc, char *argv[]) { _cleanup_free_ char *cgroup = NULL; _cleanup_(manager_freep) Manager *manager = NULL; int fd_ctrl = -1, fd_uevent = -1; int r; log_set_target(LOG_TARGET_AUTO); log_open(); udev_parse_config_full(&arg_children_max, &arg_exec_delay_usec, &arg_event_timeout_usec, &arg_resolve_name_timing, &arg_timeout_signal); log_parse_environment(); log_open(); /* Done again to update after reading configuration. */ r = parse_argv(argc, argv); if (r <= 0) return r; r = proc_cmdline_parse(parse_proc_cmdline_item, NULL, PROC_CMDLINE_STRIP_RD_PREFIX); if (r < 0) log_warning_errno(r, "Failed to parse kernel command line, ignoring: %m"); if (arg_debug) { log_set_target(LOG_TARGET_CONSOLE); log_set_max_level(LOG_DEBUG); } r = must_be_root(); if (r < 0) return r; if (arg_children_max == 0) { unsigned long cpu_limit, mem_limit, cpu_count = 1; r = cpus_in_affinity_mask(); if (r < 0) log_warning_errno(r, "Failed to determine number of local CPUs, ignoring: %m"); else cpu_count = r; cpu_limit = cpu_count * 2 + 16; mem_limit = MAX(physical_memory() / (128UL*1024*1024), 10U); arg_children_max = MIN(cpu_limit, mem_limit); arg_children_max = MIN(WORKER_NUM_MAX, arg_children_max); log_debug("Set children_max to %u", arg_children_max); } /* set umask before creating any file/directory */ umask(022); r = mac_selinux_init(); if (r < 0) return r; r = mkdir_errno_wrapper("/run/udev", 0755); if (r < 0 && r != -EEXIST) return log_error_errno(r, "Failed to create /run/udev: %m"); if (getppid() == 1 && sd_booted() > 0) { /* Get our own cgroup, we regularly kill everything udev has left behind. * We only do this on systemd systems, and only if we are directly spawned * by PID1. Otherwise we are not guaranteed to have a dedicated cgroup. */ r = cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, 0, &cgroup); if (r < 0) { if (IN_SET(r, -ENOENT, -ENOMEDIUM)) log_debug_errno(r, "Dedicated cgroup not found: %m"); else log_warning_errno(r, "Failed to get cgroup: %m"); } } r = listen_fds(&fd_ctrl, &fd_uevent); if (r < 0) return log_error_errno(r, "Failed to listen on fds: %m"); r = manager_new(&manager, fd_ctrl, fd_uevent, cgroup); if (r < 0) return log_error_errno(r, "Failed to create manager: %m"); if (arg_daemonize) { pid_t pid; log_info("Starting version " GIT_VERSION); /* connect /dev/null to stdin, stdout, stderr */ if (log_get_max_level() < LOG_DEBUG) { r = make_null_stdio(); if (r < 0) log_warning_errno(r, "Failed to redirect standard streams to /dev/null: %m"); } pid = fork(); if (pid < 0) return log_error_errno(errno, "Failed to fork daemon: %m"); if (pid > 0) /* parent */ return 0; /* child */ (void) setsid(); } return main_loop(manager); }