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-rw-r--r--src/udev/udevd.c1960
1 files changed, 1960 insertions, 0 deletions
diff --git a/src/udev/udevd.c b/src/udev/udevd.c
new file mode 100644
index 0000000..d24b8d4
--- /dev/null
+++ b/src/udev/udevd.c
@@ -0,0 +1,1960 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright © 2004 Chris Friesen <chris_friesen@sympatico.ca>
+ * Copyright © 2009 Canonical Ltd.
+ * Copyright © 2009 Scott James Remnant <scott@netsplit.com>
+ */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <getopt.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/epoll.h>
+#include <sys/file.h>
+#include <sys/inotify.h>
+#include <sys/ioctl.h>
+#include <sys/mount.h>
+#include <sys/prctl.h>
+#include <sys/signalfd.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include "sd-daemon.h"
+#include "sd-event.h"
+
+#include "alloc-util.h"
+#include "build.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 "io-util.h"
+#include "libudev-device-internal.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"
+
+#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 Manager {
+ sd_event *event;
+ Hashmap *workers;
+ LIST_HEAD(struct event, events);
+ const char *cgroup;
+ pid_t pid; /* the process that originally allocated the manager object */
+
+ UdevRules *rules;
+ Hashmap *properties;
+
+ sd_netlink *rtnl;
+
+ sd_device_monitor *monitor;
+ struct udev_ctrl *ctrl;
+ int fd_inotify;
+ int worker_watch[2];
+
+ sd_event_source *inotify_event;
+ sd_event_source *kill_workers_event;
+
+ usec_t last_usec;
+
+ bool stop_exec_queue:1;
+ bool exit:1;
+} Manager;
+
+enum event_state {
+ EVENT_UNDEF,
+ EVENT_QUEUED,
+ EVENT_RUNNING,
+};
+
+struct event {
+ Manager *manager;
+ struct worker *worker;
+ enum event_state state;
+
+ sd_device *dev;
+ sd_device *dev_kernel; /* clone of originally received device */
+
+ uint64_t seqnum;
+ uint64_t delaying_seqnum;
+
+ sd_event_source *timeout_warning_event;
+ sd_event_source *timeout_event;
+
+ LIST_FIELDS(struct event, event);
+};
+
+static void event_queue_cleanup(Manager *manager, enum event_state type);
+
+enum worker_state {
+ WORKER_UNDEF,
+ WORKER_RUNNING,
+ WORKER_IDLE,
+ WORKER_KILLED,
+};
+
+struct worker {
+ Manager *manager;
+ pid_t pid;
+ sd_device_monitor *monitor;
+ enum worker_state state;
+ struct event *event;
+};
+
+/* passed from worker to main process */
+struct worker_message {
+};
+
+static void event_free(struct event *event) {
+ if (!event)
+ return;
+
+ 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)
+ log_warning_errno(errno, "Failed to unlink /run/udev/queue: %m");
+
+ free(event);
+}
+
+static void worker_free(struct worker *worker) {
+ if (!worker)
+ return;
+
+ assert(worker->manager);
+
+ hashmap_remove(worker->manager->workers, PID_TO_PTR(worker->pid));
+ sd_device_monitor_unref(worker->monitor);
+ event_free(worker->event);
+
+ free(worker);
+}
+
+DEFINE_TRIVIAL_CLEANUP_FUNC(struct worker *, worker_free);
+DEFINE_PRIVATE_HASH_OPS_WITH_VALUE_DESTRUCTOR(worker_hash_op, void, trivial_hash_func, trivial_compare_func, struct worker, worker_free);
+
+static int worker_new(struct worker **ret, Manager *manager, sd_device_monitor *worker_monitor, pid_t pid) {
+ _cleanup_(worker_freep) struct 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(struct worker, 1);
+ if (!worker)
+ return -ENOMEM;
+
+ *worker = (struct worker) {
+ .manager = manager,
+ .monitor = sd_device_monitor_ref(worker_monitor),
+ .pid = pid,
+ };
+
+ r = hashmap_ensure_allocated(&manager->workers, &worker_hash_op);
+ if (r < 0)
+ return r;
+
+ r = hashmap_put(manager->workers, PID_TO_PTR(pid), worker);
+ if (r < 0)
+ return r;
+
+ *ret = TAKE_PTR(worker);
+
+ return 0;
+}
+
+static int on_event_timeout(sd_event_source *s, uint64_t usec, void *userdata) {
+ struct 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) {
+ struct 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(struct worker *worker, struct 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 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 void manager_free(Manager *manager) {
+ if (!manager)
+ return;
+
+ udev_builtin_exit();
+
+ if (manager->pid == getpid_cached())
+ udev_ctrl_cleanup(manager->ctrl);
+
+ manager_clear_for_worker(manager);
+
+ sd_netlink_unref(manager->rtnl);
+
+ hashmap_free_free_free(manager->properties);
+ udev_rules_free(manager->rules);
+
+ safe_close(manager->fd_inotify);
+ safe_close_pair(manager->worker_watch);
+
+ free(manager);
+}
+
+DEFINE_TRIVIAL_CLEANUP_FUNC(Manager*, manager_free);
+
+static int worker_send_message(int fd) {
+ struct worker_message 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, DEVICE_ACTION_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, DEVICE_ACTION_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;
+ DeviceAction action;
+ uint64_t seqnum;
+ int r;
+
+ assert(manager);
+ assert(dev);
+
+ r = device_get_seqnum(dev, &seqnum);
+ if (r < 0)
+ return log_device_debug_errno(dev, r, "Failed to get SEQNUM: %m");
+
+ r = device_get_action(dev, &action);
+ if (r < 0)
+ return log_device_debug_errno(dev, r, "Failed to get ACTION: %m");
+
+ log_device_debug(dev, "Processing device (SEQNUM=%"PRIu64", ACTION=%s)",
+ seqnum, device_action_to_string(action));
+
+ udev_event = udev_event_new(dev, arg_exec_delay_usec, manager->rtnl);
+ 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(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, 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);
+
+ /* apply/restore/end inotify watch */
+ if (udev_event->inotify_watch) {
+ (void) udev_watch_begin(dev);
+ r = device_update_db(dev);
+ if (r < 0)
+ return log_device_debug_errno(dev, r, "Failed to update database under /run/udev/data/: %m");
+ } else
+ (void) udev_watch_end(dev);
+
+ log_device_debug(dev, "Device (SEQNUM=%"PRIu64", ACTION=%s) processed",
+ seqnum, device_action_to_string(action));
+
+ 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");
+
+ 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 worker_spawn(Manager *manager, struct event *event) {
+ _cleanup_(sd_device_monitor_unrefp) sd_device_monitor *worker_monitor = NULL;
+ struct 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) {
+ /* 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 void event_run(Manager *manager, struct event *event) {
+ static bool log_children_max_reached = true;
+ struct worker *worker;
+ int r;
+
+ assert(manager);
+ assert(event);
+
+ if (DEBUG_LOGGING) {
+ DeviceAction action;
+
+ r = device_get_action(event->dev, &action);
+ log_device_debug(event->dev, "Device (SEQNUM=%"PRIu64", ACTION=%s) ready for processing",
+ event->seqnum, r >= 0 ? device_action_to_string(action) : "<unknown>");
+ }
+
+ 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;
+ }
+
+ 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;
+ }
+
+ /* 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 */
+ worker_spawn(manager, event);
+}
+
+static int event_queue_insert(Manager *manager, sd_device *dev) {
+ _cleanup_(sd_device_unrefp) sd_device *clone = NULL;
+ struct event *event;
+ DeviceAction action;
+ 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 = device_get_seqnum(dev, &seqnum);
+ if (r < 0)
+ return r;
+
+ /* Refuse devices do not have ACTION property. */
+ r = device_get_action(dev, &action);
+ 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(struct event, 1);
+ if (!event)
+ return -ENOMEM;
+
+ *event = (struct 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: %m");
+ }
+
+ LIST_APPEND(event, manager->events, event);
+
+ log_device_debug(dev, "Device (SEQNUM=%"PRIu64", ACTION=%s) is queued",
+ seqnum, device_action_to_string(action));
+
+ return 0;
+}
+
+static void manager_kill_workers(Manager *manager) {
+ struct worker *worker;
+
+ assert(manager);
+
+ HASHMAP_FOREACH(worker, manager->workers) {
+ if (worker->state == WORKER_KILLED)
+ continue;
+
+ worker->state = WORKER_KILLED;
+ (void) kill(worker->pid, SIGTERM);
+ }
+}
+
+/* lookup event for identical, parent, child device */
+static int is_device_busy(Manager *manager, struct event *event) {
+ const char *subsystem, *devpath, *devpath_old = NULL;
+ dev_t devnum = makedev(0, 0);
+ struct event *loop_event;
+ size_t devpath_len;
+ int r, ifindex = 0;
+ bool is_block;
+
+ 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, manager->events) {
+ size_t loop_devpath_len, common;
+ const char *loop_devpath;
+
+ /* we already found a later event, earlier cannot block us, no need to check again */
+ if (loop_event->seqnum < event->delaying_seqnum)
+ continue;
+
+ /* event we checked earlier still exists, no need to check again */
+ if (loop_event->seqnum == event->delaying_seqnum)
+ return true;
+
+ /* found ourself, no later event can block us */
+ if (loop_event->seqnum >= event->seqnum)
+ break;
+
+ /* 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"))
+ goto set_delaying_seqnum;
+ }
+
+ /* check network device ifindex */
+ if (ifindex > 0) {
+ int i;
+
+ if (sd_device_get_ifindex(loop_event->dev, &i) >= 0 &&
+ ifindex == i)
+ goto set_delaying_seqnum;
+ }
+
+ if (sd_device_get_devpath(loop_event->dev, &loop_devpath) < 0)
+ continue;
+
+ /* check our old name */
+ if (devpath_old && streq(devpath_old, loop_devpath))
+ goto set_delaying_seqnum;
+
+ 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)
+ goto set_delaying_seqnum;
+
+ /* parent device event found */
+ if (devpath[common] == '/')
+ goto set_delaying_seqnum;
+
+ /* child device event found */
+ if (loop_devpath[common] == '/')
+ goto set_delaying_seqnum;
+ }
+
+ return false;
+
+set_delaying_seqnum:
+ log_device_debug(event->dev, "SEQNUM=%" PRIu64 " blocked by SEQNUM=%" PRIu64,
+ event->seqnum, loop_event->seqnum);
+
+ event->delaying_seqnum = loop_event->seqnum;
+ return true;
+}
+
+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->fd_inotify = safe_close(manager->fd_inotify);
+
+ manager->monitor = sd_device_monitor_unref(manager->monitor);
+
+ /* discard queued events and kill workers */
+ event_queue_cleanup(manager, EVENT_QUEUED);
+ manager_kill_workers(manager);
+}
+
+/* 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);
+ 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);
+
+ return 1;
+}
+
+static void event_queue_start(Manager *manager) {
+ struct event *event;
+ usec_t usec;
+ int r;
+
+ assert(manager);
+
+ if (LIST_IS_EMPTY(manager->events) ||
+ manager->exit || manager->stop_exec_queue)
+ return;
+
+ 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 - 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) {
+ log_warning_errno(r, "Failed to read udev rules: %m");
+ return;
+ }
+ }
+
+ LIST_FOREACH(event, event, manager->events) {
+ if (event->state != EVENT_QUEUED)
+ continue;
+
+ /* do not start event if parent or child event is still running */
+ if (is_device_busy(manager, event) != 0)
+ continue;
+
+ event_run(manager, event);
+ }
+}
+
+static void event_queue_cleanup(Manager *manager, enum event_state match_type) {
+ struct event *event, *tmp;
+
+ LIST_FOREACH_SAFE(event, event, tmp, manager->events) {
+ if (match_type != EVENT_UNDEF && match_type != event->state)
+ continue;
+
+ event_free(event);
+ }
+}
+
+static int on_worker(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
+ Manager *manager = userdata;
+
+ assert(manager);
+
+ for (;;) {
+ struct worker_message 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;
+ struct 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(struct worker_message)) {
+ 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_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;
+}
+
+static int on_uevent(sd_device_monitor *monitor, sd_device *dev, void *userdata) {
+ Manager *manager = userdata;
+ int r;
+
+ assert(manager);
+
+ 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;
+}
+
+/* receive the udevd message from userspace */
+static int on_ctrl_msg(struct udev_ctrl *uctrl, enum udev_ctrl_msg_type type, const union udev_ctrl_msg_value *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_realm(LOG_REALM_UDEV, value->intval);
+ log_set_max_level_realm(LOG_REALM_SYSTEMD, value->intval);
+ manager_kill_workers(manager);
+ 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: {
+ _cleanup_free_ char *key = NULL, *val = NULL, *old_key = NULL, *old_val = 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);
+ 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, const char *syspath) {
+ const char *filename;
+ int r;
+
+ filename = strjoina(syspath, "/uevent");
+ log_device_debug(dev, "device is closed, synthesising 'change' on %s", syspath);
+ r = write_string_file(filename, "change", WRITE_STRING_FILE_DISABLE_BUFFER);
+ if (r < 0)
+ return log_device_debug_errno(dev, r, "Failed to write 'change' to %s: %m", filename);
+ return 0;
+}
+
+static int synthesize_change(sd_device *dev) {
+ const char *subsystem, *sysname, *devname, *syspath, *devtype;
+ int r;
+
+ r = sd_device_get_subsystem(dev, &subsystem);
+ if (r < 0)
+ return r;
+
+ r = sd_device_get_sysname(dev, &sysname);
+ if (r < 0)
+ return r;
+
+ r = sd_device_get_devname(dev, &devname);
+ if (r < 0)
+ return r;
+
+ r = sd_device_get_syspath(dev, &syspath);
+ if (r < 0)
+ return r;
+
+ r = sd_device_get_devtype(dev, &devtype);
+ if (r < 0)
+ return r;
+
+ if (streq_ptr("block", subsystem) &&
+ streq_ptr("disk", devtype) &&
+ !startswith(sysname, "dm-")) {
+ _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
+ bool part_table_read = false, has_partitions = false;
+ sd_device *d;
+ int fd;
+
+ /*
+ * 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("partition", t))
+ 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, syspath);
+
+ FOREACH_DEVICE(e, d) {
+ const char *t, *n, *s;
+
+ if (sd_device_get_devtype(d, &t) < 0 ||
+ !streq("partition", t))
+ continue;
+
+ if (sd_device_get_devname(d, &n) < 0 ||
+ sd_device_get_syspath(d, &s) < 0)
+ continue;
+
+ (void) synthesize_change_one(dev, s);
+ }
+
+ } else
+ (void) synthesize_change_one(dev, syspath);
+
+ 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;
+
+ if (udev_watch_lookup(e->wd, &dev) <= 0)
+ 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)
+ synthesize_change(dev);
+ else if (e->mask & IN_IGNORED)
+ udev_watch_end(dev);
+ }
+
+ 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;
+ struct 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=<level> syslog priority
+ * udev.children_max=<number of workers> events are fully serialized if set to 1
+ * udev.exec_delay=<number of seconds> delay execution of every executed program
+ * udev.event_timeout=<number of seconds> 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("Unhandled option");
+
+ }
+ }
+
+ 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) {
+ .fd_inotify = -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");
+
+ *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");
+
+ r = udev_watch_init();
+ if (r < 0)
+ return log_error_errno(r, "Failed to create inotify descriptor: %m");
+ manager->fd_inotify = r;
+
+ udev_watch_restore();
+
+ /* 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->fd_inotify, 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);
+ }
+
+ log_set_max_level_realm(LOG_REALM_SYSTEMD, log_get_max_level());
+
+ 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);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-18 23:50:20 +0000