src/udev/udevd.c

   1 /*
   2  * Copyright (C) 2004-2012 Kay Sievers <kay@vrfy.org>
   3  * Copyright (C) 2004 Chris Friesen <chris_friesen@sympatico.ca>
   4  * Copyright (C) 2009 Canonical Ltd.
   5  * Copyright (C) 2009 Scott James Remnant <scott@netsplit.com>
   6  *
   7  * This program is free software: you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation, either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include <stddef.h>
  22 #include <signal.h>
  23 #include <unistd.h>
  24 #include <errno.h>
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <stdbool.h>
  28 #include <string.h>
  29 #include <ctype.h>
  30 #include <fcntl.h>
  31 #include <time.h>
  32 #include <getopt.h>
  33 #include <dirent.h>
  34 #include <sys/file.h>
  35 #include <sys/time.h>
  36 #include <sys/prctl.h>
  37 #include <sys/socket.h>
  38 #include <sys/un.h>
  39 #include <sys/signalfd.h>
  40 #include <sys/epoll.h>
  41 #include <sys/poll.h>
  42 #include <sys/wait.h>
  43 #include <sys/stat.h>
  44 #include <sys/ioctl.h>
  45 #include <sys/inotify.h>
  46 #include <sys/utsname.h>
  47
  48 #include "udev.h"
  49 #include "sd-daemon.h"
  50 #include "cgroup-util.h"
  51 #include "dev-setup.h"
  52 #include "fileio.h"
  53
  54 static bool debug;
  55
  56 void udev_main_log(struct udev *udev, int priority,
  57                    const char *file, int line, const char *fn,
  58                    const char *format, va_list args)
  59 {
  60         log_metav(priority, file, line, fn, format, args);
  61 }
  62
  63 static struct udev_rules *rules;
  64 static struct udev_ctrl *udev_ctrl;
  65 static struct udev_monitor *monitor;
  66 static int worker_watch[2] = { -1, -1 };
  67 static int fd_signal = -1;
  68 static int fd_ep = -1;
  69 static int fd_inotify = -1;
  70 static bool stop_exec_queue;
  71 static bool reload;
  72 static int children;
  73 static int children_max;
  74 static int exec_delay;
  75 static sigset_t sigmask_orig;
  76 static UDEV_LIST(event_list);
  77 static UDEV_LIST(worker_list);
  78 static char *udev_cgroup;
  79 static bool udev_exit;
  80
  81 enum event_state {
  82         EVENT_UNDEF,
  83         EVENT_QUEUED,
  84         EVENT_RUNNING,
  85 };
  86
  87 struct event {
  88         struct udev_list_node node;
  89         struct udev *udev;
  90         struct udev_device *dev;
  91         enum event_state state;
  92         int exitcode;
  93         unsigned long long int delaying_seqnum;
  94         unsigned long long int seqnum;
  95         const char *devpath;
  96         size_t devpath_len;
  97         const char *devpath_old;
  98         dev_t devnum;
  99         int ifindex;
 100         bool is_block;
 101 #ifdef HAVE_FIRMWARE
 102         bool nodelay;
 103 #endif
 104 };
 105
 106 static inline struct event *node_to_event(struct udev_list_node *node)
 107 {
 108         return container_of(node, struct event, node);
 109 }
 110
 111 static void event_queue_cleanup(struct udev *udev, enum event_state type);
 112
 113 enum worker_state {
 114         WORKER_UNDEF,
 115         WORKER_RUNNING,
 116         WORKER_IDLE,
 117         WORKER_KILLED,
 118 };
 119
 120 struct worker {
 121         struct udev_list_node node;
 122         struct udev *udev;
 123         int refcount;
 124         pid_t pid;
 125         struct udev_monitor *monitor;
 126         enum worker_state state;
 127         struct event *event;
 128         usec_t event_start_usec;
 129 };
 130
 131 /* passed from worker to main process */
 132 struct worker_message {
 133         pid_t pid;
 134         int exitcode;
 135 };
 136
 137 static inline struct worker *node_to_worker(struct udev_list_node *node)
 138 {
 139         return container_of(node, struct worker, node);
 140 }
 141
 142 static void event_queue_delete(struct event *event)
 143 {
 144         udev_list_node_remove(&event->node);
 145         udev_device_unref(event->dev);
 146         free(event);
 147 }
 148
 149 static struct worker *worker_ref(struct worker *worker)
 150 {
 151         worker->refcount++;
 152         return worker;
 153 }
 154
 155 static void worker_cleanup(struct worker *worker)
 156 {
 157         udev_list_node_remove(&worker->node);
 158         udev_monitor_unref(worker->monitor);
 159         children--;
 160         free(worker);
 161 }
 162
 163 static void worker_unref(struct worker *worker)
 164 {
 165         worker->refcount--;
 166         if (worker->refcount > 0)
 167                 return;
 168         log_debug("worker [%u] cleaned up", worker->pid);
 169         worker_cleanup(worker);
 170 }
 171
 172 static void worker_list_cleanup(struct udev *udev)
 173 {
 174         struct udev_list_node *loop, *tmp;
 175
 176         udev_list_node_foreach_safe(loop, tmp, &worker_list) {
 177                 struct worker *worker = node_to_worker(loop);
 178
 179                 worker_cleanup(worker);
 180         }
 181 }
 182
 183 static void worker_new(struct event *event)
 184 {
 185         struct udev *udev = event->udev;
 186         struct worker *worker;
 187         struct udev_monitor *worker_monitor;
 188         pid_t pid;
 189
 190         /* listen for new events */
 191         worker_monitor = udev_monitor_new_from_netlink(udev, NULL);
 192         if (worker_monitor == NULL)
 193                 return;
 194         /* allow the main daemon netlink address to send devices to the worker */
 195         udev_monitor_allow_unicast_sender(worker_monitor, monitor);
 196         udev_monitor_enable_receiving(worker_monitor);
 197
 198         worker = new0(struct worker, 1);
 199         if (worker == NULL) {
 200                 udev_monitor_unref(worker_monitor);
 201                 return;
 202         }
 203         /* worker + event reference */
 204         worker->refcount = 2;
 205         worker->udev = udev;
 206
 207         pid = fork();
 208         switch (pid) {
 209         case 0: {
 210                 struct udev_device *dev = NULL;
 211                 int fd_monitor;
 212                 struct epoll_event ep_signal, ep_monitor;
 213                 sigset_t mask;
 214                 int rc = EXIT_SUCCESS;
 215
 216                 /* take initial device from queue */
 217                 dev = event->dev;
 218                 event->dev = NULL;
 219
 220                 free(worker);
 221                 worker_list_cleanup(udev);
 222                 event_queue_cleanup(udev, EVENT_UNDEF);
 223                 udev_monitor_unref(monitor);
 224                 udev_ctrl_unref(udev_ctrl);
 225                 close(fd_signal);
 226                 close(fd_ep);
 227                 close(worker_watch[READ_END]);
 228
 229                 sigfillset(&mask);
 230                 fd_signal = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
 231                 if (fd_signal < 0) {
 232                         log_error("error creating signalfd %m");
 233                         rc = 2;
 234                         goto out;
 235                 }
 236
 237                 fd_ep = epoll_create1(EPOLL_CLOEXEC);
 238                 if (fd_ep < 0) {
 239                         log_error("error creating epoll fd: %m");
 240                         rc = 3;
 241                         goto out;
 242                 }
 243
 244                 memzero(&ep_signal, sizeof(struct epoll_event));
 245                 ep_signal.events = EPOLLIN;
 246                 ep_signal.data.fd = fd_signal;
 247
 248                 fd_monitor = udev_monitor_get_fd(worker_monitor);
 249                 memzero(&ep_monitor, sizeof(struct epoll_event));
 250                 ep_monitor.events = EPOLLIN;
 251                 ep_monitor.data.fd = fd_monitor;
 252
 253                 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_signal, &ep_signal) < 0 ||
 254                     epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_monitor, &ep_monitor) < 0) {
 255                         log_error("fail to add fds to epoll: %m");
 256                         rc = 4;
 257                         goto out;
 258                 }
 259
 260                 /* request TERM signal if parent exits */
 261                 prctl(PR_SET_PDEATHSIG, SIGTERM);
 262
 263                 /* reset OOM score, we only protect the main daemon */
 264                 write_string_file("/proc/self/oom_score_adj", "0");
 265
 266                 for (;;) {
 267                         struct udev_event *udev_event;
 268                         struct worker_message msg;
 269                         int fd_lock = -1;
 270                         int err = 0;
 271
 272                         log_debug("seq %llu running", udev_device_get_seqnum(dev));
 273                         udev_event = udev_event_new(dev);
 274                         if (udev_event == NULL) {
 275                                 rc = 5;
 276                                 goto out;
 277                         }
 278
 279                         /* needed for SIGCHLD/SIGTERM in spawn() */
 280                         udev_event->fd_signal = fd_signal;
 281
 282                         if (exec_delay > 0)
 283                                 udev_event->exec_delay = exec_delay;
 284
 285                         /*
 286                          * Take a "read lock" on the device node; this establishes
 287                          * a concept of device "ownership" to serialize device
 288                          * access. External processes holding a "write lock" will
 289                          * cause udev to skip the event handling; in the case udev
 290                          * acquired the lock, the external process will block until
 291                          * udev has finished its event handling.
 292                          */
 293                         if (streq_ptr("block", udev_device_get_subsystem(dev))) {
 294                                 struct udev_device *d = dev;
 295
 296                                 if (streq_ptr("partition", udev_device_get_devtype(d)))
 297                                         d = udev_device_get_parent(d);
 298
 299                                 if (d) {
 300                                         fd_lock = open(udev_device_get_devnode(d), O_RDONLY|O_CLOEXEC|O_NOFOLLOW|O_NONBLOCK);
 301                                         if (fd_lock >= 0 && flock(fd_lock, LOCK_SH|LOCK_NB) < 0) {
 302                                                 log_debug("Unable to flock(%s), skipping event handling: %m", udev_device_get_devnode(d));
 303                                                 err = -EWOULDBLOCK;
 304                                                 fd_lock = safe_close(fd_lock);
 305                                                 goto skip;
 306                                         }
 307                                 }
 308                         }
 309
 310                         /* apply rules, create node, symlinks */
 311                         udev_event_execute_rules(udev_event, rules, &sigmask_orig);
 312
 313                         udev_event_execute_run(udev_event, &sigmask_orig);
 314
 315                         /* apply/restore inotify watch */
 316                         if (udev_event->inotify_watch) {
 317                                 udev_watch_begin(udev, dev);
 318                                 udev_device_update_db(dev);
 319                         }
 320
 321                         safe_close(fd_lock);
 322
 323                         /* send processed event back to libudev listeners */
 324                         udev_monitor_send_device(worker_monitor, NULL, dev);
 325
 326 skip:
 327                         /* send udevd the result of the event execution */
 328                         memzero(&msg, sizeof(struct worker_message));
 329                         msg.exitcode = err;
 330                         msg.pid = getpid();
 331                         send(worker_watch[WRITE_END], &msg, sizeof(struct worker_message), 0);
 332
 333                         log_debug("seq %llu processed with %i", udev_device_get_seqnum(dev), err);
 334
 335                         udev_device_unref(dev);
 336                         dev = NULL;
 337
 338                         if (udev_event->sigterm) {
 339                                 udev_event_unref(udev_event);
 340                                 goto out;
 341                         }
 342
 343                         udev_event_unref(udev_event);
 344
 345                         /* wait for more device messages from main udevd, or term signal */
 346                         while (dev == NULL) {
 347                                 struct epoll_event ev[4];
 348                                 int fdcount;
 349                                 int i;
 350
 351                                 fdcount = epoll_wait(fd_ep, ev, ELEMENTSOF(ev), -1);
 352                                 if (fdcount < 0) {
 353                                         if (errno == EINTR)
 354                                                 continue;
 355                                         log_error("failed to poll: %m");
 356                                         goto out;
 357                                 }
 358
 359                                 for (i = 0; i < fdcount; i++) {
 360                                         if (ev[i].data.fd == fd_monitor && ev[i].events & EPOLLIN) {
 361                                                 dev = udev_monitor_receive_device(worker_monitor);
 362                                                 break;
 363                                         } else if (ev[i].data.fd == fd_signal && ev[i].events & EPOLLIN) {
 364                                                 struct signalfd_siginfo fdsi;
 365                                                 ssize_t size;
 366
 367                                                 size = read(fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
 368                                                 if (size != sizeof(struct signalfd_siginfo))
 369                                                         continue;
 370                                                 switch (fdsi.ssi_signo) {
 371                                                 case SIGTERM:
 372                                                         goto out;
 373                                                 }
 374                                         }
 375                                 }
 376                         }
 377                 }
 378 out:
 379                 udev_device_unref(dev);
 380                 safe_close(fd_signal);
 381                 safe_close(fd_ep);
 382                 close(fd_inotify);
 383                 close(worker_watch[WRITE_END]);
 384                 udev_rules_unref(rules);
 385                 udev_builtin_exit(udev);
 386                 udev_monitor_unref(worker_monitor);
 387                 udev_unref(udev);
 388                 log_close();
 389                 exit(rc);
 390         }
 391         case -1:
 392                 udev_monitor_unref(worker_monitor);
 393                 event->state = EVENT_QUEUED;
 394                 free(worker);
 395                 log_error("fork of child failed: %m");
 396                 break;
 397         default:
 398                 /* close monitor, but keep address around */
 399                 udev_monitor_disconnect(worker_monitor);
 400                 worker->monitor = worker_monitor;
 401                 worker->pid = pid;
 402                 worker->state = WORKER_RUNNING;
 403                 worker->event_start_usec = now(CLOCK_MONOTONIC);
 404                 worker->event = event;
 405                 event->state = EVENT_RUNNING;
 406                 udev_list_node_append(&worker->node, &worker_list);
 407                 children++;
 408                 log_debug("seq %llu forked new worker [%u]", udev_device_get_seqnum(event->dev), pid);
 409                 break;
 410         }
 411 }
 412
 413 static void event_run(struct event *event)
 414 {
 415         struct udev_list_node *loop;
 416
 417         udev_list_node_foreach(loop, &worker_list) {
 418                 struct worker *worker = node_to_worker(loop);
 419                 ssize_t count;
 420
 421                 if (worker->state != WORKER_IDLE)
 422                         continue;
 423
 424                 count = udev_monitor_send_device(monitor, worker->monitor, event->dev);
 425                 if (count < 0) {
 426                         log_error("worker [%u] did not accept message %zi (%m), kill it", worker->pid, count);
 427                         kill(worker->pid, SIGKILL);
 428                         worker->state = WORKER_KILLED;
 429                         continue;
 430                 }
 431                 worker_ref(worker);
 432                 worker->event = event;
 433                 worker->state = WORKER_RUNNING;
 434                 worker->event_start_usec = now(CLOCK_MONOTONIC);
 435                 event->state = EVENT_RUNNING;
 436                 return;
 437         }
 438
 439         if (children >= children_max) {
 440                 if (children_max > 1)
 441                         log_debug("maximum number (%i) of children reached", children);
 442                 return;
 443         }
 444
 445         /* start new worker and pass initial device */
 446         worker_new(event);
 447 }
 448
 449 static int event_queue_insert(struct udev_device *dev)
 450 {
 451         struct event *event;
 452
 453         event = new0(struct event, 1);
 454         if (event == NULL)
 455                 return -1;
 456
 457         event->udev = udev_device_get_udev(dev);
 458         event->dev = dev;
 459         event->seqnum = udev_device_get_seqnum(dev);
 460         event->devpath = udev_device_get_devpath(dev);
 461         event->devpath_len = strlen(event->devpath);
 462         event->devpath_old = udev_device_get_devpath_old(dev);
 463         event->devnum = udev_device_get_devnum(dev);
 464         event->is_block = streq("block", udev_device_get_subsystem(dev));
 465         event->ifindex = udev_device_get_ifindex(dev);
 466 #ifdef HAVE_FIRMWARE
 467         if (streq(udev_device_get_subsystem(dev), "firmware"))
 468                 event->nodelay = true;
 469 #endif
 470
 471         log_debug("seq %llu queued, '%s' '%s'", udev_device_get_seqnum(dev),
 472              udev_device_get_action(dev), udev_device_get_subsystem(dev));
 473
 474         event->state = EVENT_QUEUED;
 475         udev_list_node_append(&event->node, &event_list);
 476         return 0;
 477 }
 478
 479 static void worker_kill(struct udev *udev)
 480 {
 481         struct udev_list_node *loop;
 482
 483         udev_list_node_foreach(loop, &worker_list) {
 484                 struct worker *worker = node_to_worker(loop);
 485
 486                 if (worker->state == WORKER_KILLED)
 487                         continue;
 488
 489                 worker->state = WORKER_KILLED;
 490                 kill(worker->pid, SIGTERM);
 491         }
 492 }
 493
 494 /* lookup event for identical, parent, child device */
 495 static bool is_devpath_busy(struct event *event)
 496 {
 497         struct udev_list_node *loop;
 498         size_t common;
 499
 500         /* check if queue contains events we depend on */
 501         udev_list_node_foreach(loop, &event_list) {
 502                 struct event *loop_event = node_to_event(loop);
 503
 504                 /* we already found a later event, earlier can not block us, no need to check again */
 505                 if (loop_event->seqnum < event->delaying_seqnum)
 506                         continue;
 507
 508                 /* event we checked earlier still exists, no need to check again */
 509                 if (loop_event->seqnum == event->delaying_seqnum)
 510                         return true;
 511
 512                 /* found ourself, no later event can block us */
 513                 if (loop_event->seqnum >= event->seqnum)
 514                         break;
 515
 516                 /* check major/minor */
 517                 if (major(event->devnum) != 0 && event->devnum == loop_event->devnum && event->is_block == loop_event->is_block)
 518                         return true;
 519
 520                 /* check network device ifindex */
 521                 if (event->ifindex != 0 && event->ifindex == loop_event->ifindex)
 522                         return true;
 523
 524                 /* check our old name */
 525                 if (event->devpath_old != NULL && streq(loop_event->devpath, event->devpath_old)) {
 526                         event->delaying_seqnum = loop_event->seqnum;
 527                         return true;
 528                 }
 529
 530                 /* compare devpath */
 531                 common = MIN(loop_event->devpath_len, event->devpath_len);
 532
 533                 /* one devpath is contained in the other? */
 534                 if (memcmp(loop_event->devpath, event->devpath, common) != 0)
 535                         continue;
 536
 537                 /* identical device event found */
 538                 if (loop_event->devpath_len == event->devpath_len) {
 539                         /* devices names might have changed/swapped in the meantime */
 540                         if (major(event->devnum) != 0 && (event->devnum != loop_event->devnum || event->is_block != loop_event->is_block))
 541                                 continue;
 542                         if (event->ifindex != 0 && event->ifindex != loop_event->ifindex)
 543                                 continue;
 544                         event->delaying_seqnum = loop_event->seqnum;
 545                         return true;
 546                 }
 547
 548 #ifdef HAVE_FIRMWARE
 549                 /* allow to bypass the dependency tracking */
 550                 if (event->nodelay)
 551                         continue;
 552 #endif
 553
 554                 /* parent device event found */
 555                 if (event->devpath[common] == '/') {
 556                         event->delaying_seqnum = loop_event->seqnum;
 557                         return true;
 558                 }
 559
 560                 /* child device event found */
 561                 if (loop_event->devpath[common] == '/') {
 562                         event->delaying_seqnum = loop_event->seqnum;
 563                         return true;
 564                 }
 565
 566                 /* no matching device */
 567                 continue;
 568         }
 569
 570         return false;
 571 }
 572
 573 static void event_queue_start(struct udev *udev)
 574 {
 575         struct udev_list_node *loop;
 576
 577         udev_list_node_foreach(loop, &event_list) {
 578                 struct event *event = node_to_event(loop);
 579
 580                 if (event->state != EVENT_QUEUED)
 581                         continue;
 582
 583                 /* do not start event if parent or child event is still running */
 584                 if (is_devpath_busy(event))
 585                         continue;
 586
 587                 event_run(event);
 588         }
 589 }
 590
 591 static void event_queue_cleanup(struct udev *udev, enum event_state match_type)
 592 {
 593         struct udev_list_node *loop, *tmp;
 594
 595         udev_list_node_foreach_safe(loop, tmp, &event_list) {
 596                 struct event *event = node_to_event(loop);
 597
 598                 if (match_type != EVENT_UNDEF && match_type != event->state)
 599                         continue;
 600
 601                 event_queue_delete(event);
 602         }
 603 }
 604
 605 static void worker_returned(int fd_worker)
 606 {
 607         for (;;) {
 608                 struct worker_message msg;
 609                 ssize_t size;
 610                 struct udev_list_node *loop;
 611
 612                 size = recv(fd_worker, &msg, sizeof(struct worker_message), MSG_DONTWAIT);
 613                 if (size != sizeof(struct worker_message))
 614                         break;
 615
 616                 /* lookup worker who sent the signal */
 617                 udev_list_node_foreach(loop, &worker_list) {
 618                         struct worker *worker = node_to_worker(loop);
 619
 620                         if (worker->pid != msg.pid)
 621                                 continue;
 622
 623                         /* worker returned */
 624                         if (worker->event) {
 625                                 worker->event->exitcode = msg.exitcode;
 626                                 event_queue_delete(worker->event);
 627                                 worker->event = NULL;
 628                         }
 629                         if (worker->state != WORKER_KILLED)
 630                                 worker->state = WORKER_IDLE;
 631                         worker_unref(worker);
 632                         break;
 633                 }
 634         }
 635 }
 636
 637 /* receive the udevd message from userspace */
 638 static struct udev_ctrl_connection *handle_ctrl_msg(struct udev_ctrl *uctrl)
 639 {
 640         struct udev *udev = udev_ctrl_get_udev(uctrl);
 641         struct udev_ctrl_connection *ctrl_conn;
 642         struct udev_ctrl_msg *ctrl_msg = NULL;
 643         const char *str;
 644         int i;
 645
 646         ctrl_conn = udev_ctrl_get_connection(uctrl);
 647         if (ctrl_conn == NULL)
 648                 goto out;
 649
 650         ctrl_msg = udev_ctrl_receive_msg(ctrl_conn);
 651         if (ctrl_msg == NULL)
 652                 goto out;
 653
 654         i = udev_ctrl_get_set_log_level(ctrl_msg);
 655         if (i >= 0) {
 656                 log_debug("udevd message (SET_LOG_LEVEL) received, log_priority=%i", i);
 657                 log_set_max_level(i);
 658                 udev_set_log_priority(udev, i);
 659                 worker_kill(udev);
 660         }
 661
 662         if (udev_ctrl_get_stop_exec_queue(ctrl_msg) > 0) {
 663                 log_debug("udevd message (STOP_EXEC_QUEUE) received");
 664                 stop_exec_queue = true;
 665         }
 666
 667         if (udev_ctrl_get_start_exec_queue(ctrl_msg) > 0) {
 668                 log_debug("udevd message (START_EXEC_QUEUE) received");
 669                 stop_exec_queue = false;
 670         }
 671
 672         if (udev_ctrl_get_reload(ctrl_msg) > 0) {
 673                 log_debug("udevd message (RELOAD) received");
 674                 reload = true;
 675         }
 676
 677         str = udev_ctrl_get_set_env(ctrl_msg);
 678         if (str != NULL) {
 679                 char *key;
 680
 681                 key = strdup(str);
 682                 if (key != NULL) {
 683                         char *val;
 684
 685                         val = strchr(key, '=');
 686                         if (val != NULL) {
 687                                 val[0] = '\0';
 688                                 val = &val[1];
 689                                 if (val[0] == '\0') {
 690                                         log_debug("udevd message (ENV) received, unset '%s'", key);
 691                                         udev_add_property(udev, key, NULL);
 692                                 } else {
 693                                         log_debug("udevd message (ENV) received, set '%s=%s'", key, val);
 694                                         udev_add_property(udev, key, val);
 695                                 }
 696                         } else {
 697                                 log_error("wrong key format '%s'", key);
 698                         }
 699                         free(key);
 700                 }
 701                 worker_kill(udev);
 702         }
 703
 704         i = udev_ctrl_get_set_children_max(ctrl_msg);
 705         if (i >= 0) {
 706                 log_debug("udevd message (SET_MAX_CHILDREN) received, children_max=%i", i);
 707                 children_max = i;
 708         }
 709
 710         if (udev_ctrl_get_ping(ctrl_msg) > 0)
 711                 log_debug("udevd message (SYNC) received");
 712
 713         if (udev_ctrl_get_exit(ctrl_msg) > 0) {
 714                 log_debug("udevd message (EXIT) received");
 715                 udev_exit = true;
 716                 /* keep reference to block the client until we exit */
 717                 udev_ctrl_connection_ref(ctrl_conn);
 718         }
 719 out:
 720         udev_ctrl_msg_unref(ctrl_msg);
 721         return udev_ctrl_connection_unref(ctrl_conn);
 722 }
 723
 724 /* read inotify messages */
 725 static int handle_inotify(struct udev *udev)
 726 {
 727         int nbytes, pos;
 728         char *buf;
 729         struct inotify_event *ev;
 730
 731         if ((ioctl(fd_inotify, FIONREAD, &nbytes) < 0) || (nbytes <= 0))
 732                 return 0;
 733
 734         buf = malloc(nbytes);
 735         if (buf == NULL) {
 736                 log_error("error getting buffer for inotify");
 737                 return -1;
 738         }
 739
 740         nbytes = read(fd_inotify, buf, nbytes);
 741
 742         for (pos = 0; pos < nbytes; pos += sizeof(struct inotify_event) + ev->len) {
 743                 struct udev_device *dev;
 744
 745                 ev = (struct inotify_event *)(buf + pos);
 746                 dev = udev_watch_lookup(udev, ev->wd);
 747                 if (dev != NULL) {
 748                         log_debug("inotify event: %x for %s", ev->mask, udev_device_get_devnode(dev));
 749                         if (ev->mask & IN_CLOSE_WRITE) {
 750                                 char filename[UTIL_PATH_SIZE];
 751                                 int fd;
 752
 753                                 log_debug("device %s closed, synthesising 'change'", udev_device_get_devnode(dev));
 754                                 strscpyl(filename, sizeof(filename), udev_device_get_syspath(dev), "/uevent", NULL);
 755                                 fd = open(filename, O_WRONLY|O_CLOEXEC);
 756                                 if (fd >= 0) {
 757                                         if (write(fd, "change", 6) < 0)
 758                                                 log_debug("error writing uevent: %m");
 759                                         close(fd);
 760                                 }
 761                         }
 762                         if (ev->mask & IN_IGNORED)
 763                                 udev_watch_end(udev, dev);
 764
 765                         udev_device_unref(dev);
 766                 }
 767
 768         }
 769
 770         free(buf);
 771         return 0;
 772 }
 773
 774 static void handle_signal(struct udev *udev, int signo)
 775 {
 776         switch (signo) {
 777         case SIGINT:
 778         case SIGTERM:
 779                 udev_exit = true;
 780                 break;
 781         case SIGCHLD:
 782                 for (;;) {
 783                         pid_t pid;
 784                         int status;
 785                         struct udev_list_node *loop, *tmp;
 786
 787                         pid = waitpid(-1, &status, WNOHANG);
 788                         if (pid <= 0)
 789                                 break;
 790
 791                         udev_list_node_foreach_safe(loop, tmp, &worker_list) {
 792                                 struct worker *worker = node_to_worker(loop);
 793
 794                                 if (worker->pid != pid)
 795                                         continue;
 796                                 log_debug("worker [%u] exit", pid);
 797
 798                                 if (WIFEXITED(status)) {
 799                                         if (WEXITSTATUS(status) != 0)
 800                                                 log_error("worker [%u] exit with return code %i",
 801                                                           pid, WEXITSTATUS(status));
 802                                 } else if (WIFSIGNALED(status)) {
 803                                         log_error("worker [%u] terminated by signal %i (%s)",
 804                                                   pid, WTERMSIG(status), strsignal(WTERMSIG(status)));
 805                                 } else if (WIFSTOPPED(status)) {
 806                                         log_error("worker [%u] stopped", pid);
 807                                 } else if (WIFCONTINUED(status)) {
 808                                         log_error("worker [%u] continued", pid);
 809                                 } else {
 810                                         log_error("worker [%u] exit with status 0x%04x", pid, status);
 811                                 }
 812
 813                                 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
 814                                         if (worker->event) {
 815                                                 log_error("worker [%u] failed while handling '%s'",
 816                                                           pid, worker->event->devpath);
 817                                                 worker->event->exitcode = -32;
 818                                                 event_queue_delete(worker->event);
 819
 820                                                 /* drop reference taken for state 'running' */
 821                                                 worker_unref(worker);
 822                                         }
 823                                 }
 824                                 worker_unref(worker);
 825                                 break;
 826                         }
 827                 }
 828                 break;
 829         case SIGHUP:
 830                 reload = true;
 831                 break;
 832         }
 833 }
 834
 835 static int systemd_fds(struct udev *udev, int *rctrl, int *rnetlink)
 836 {
 837         int ctrl = -1, netlink = -1;
 838         int fd, n;
 839
 840         n = sd_listen_fds(true);
 841         if (n <= 0)
 842                 return -1;
 843
 844         for (fd = SD_LISTEN_FDS_START; fd < n + SD_LISTEN_FDS_START; fd++) {
 845                 if (sd_is_socket(fd, AF_LOCAL, SOCK_SEQPACKET, -1)) {
 846                         if (ctrl >= 0)
 847                                 return -1;
 848                         ctrl = fd;
 849                         continue;
 850                 }
 851
 852                 if (sd_is_socket(fd, AF_NETLINK, SOCK_RAW, -1)) {
 853                         if (netlink >= 0)
 854                                 return -1;
 855                         netlink = fd;
 856                         continue;
 857                 }
 858
 859                 return -1;
 860         }
 861
 862         if (ctrl < 0 || netlink < 0)
 863                 return -1;
 864
 865         log_debug("ctrl=%i netlink=%i", ctrl, netlink);
 866         *rctrl = ctrl;
 867         *rnetlink = netlink;
 868         return 0;
 869 }
 870
 871 /*
 872  * read the kernel commandline, in case we need to get into debug mode
 873  *   udev.log-priority=<level>              syslog priority
 874  *   udev.children-max=<number of workers>  events are fully serialized if set to 1
 875  *   udev.exec-delay=<number of seconds>    delay execution of every executed program
 876  */
 877 static void kernel_cmdline_options(struct udev *udev)
 878 {
 879         _cleanup_free_ char *line = NULL;
 880         char *w, *state;
 881         size_t l;
 882         int r;
 883
 884         r = proc_cmdline(&line);
 885         if (r < 0)
 886                 log_warning("Failed to read /proc/cmdline, ignoring: %s", strerror(-r));
 887         if (r <= 0)
 888                 return;
 889
 890         FOREACH_WORD_QUOTED(w, l, line, state) {
 891                 char *s, *opt;
 892
 893                 s = strndup(w, l);
 894                 if (!s)
 895                         break;
 896
 897                 /* accept the same options for the initrd, prefixed with "rd." */
 898                 if (in_initrd() && startswith(s, "rd."))
 899                         opt = s + 3;
 900                 else
 901                         opt = s;
 902
 903                 if (startswith(opt, "udev.log-priority=")) {
 904                         int prio;
 905
 906                         prio = util_log_priority(opt + 18);
 907                         log_set_max_level(prio);
 908                         udev_set_log_priority(udev, prio);
 909                 } else if (startswith(opt, "udev.children-max=")) {
 910                         children_max = strtoul(opt + 18, NULL, 0);
 911                 } else if (startswith(opt, "udev.exec-delay=")) {
 912                         exec_delay = strtoul(opt + 16, NULL, 0);
 913                 }
 914
 915                 free(s);
 916         }
 917 }
 918
 919 int main(int argc, char *argv[])
 920 {
 921         struct udev *udev;
 922         sigset_t mask;
 923         int daemonize = false;
 924         int resolve_names = 1;
 925         static const struct option options[] = {
 926                 { "daemon", no_argument, NULL, 'd' },
 927                 { "debug", no_argument, NULL, 'D' },
 928                 { "children-max", required_argument, NULL, 'c' },
 929                 { "exec-delay", required_argument, NULL, 'e' },
 930                 { "resolve-names", required_argument, NULL, 'N' },
 931                 { "help", no_argument, NULL, 'h' },
 932                 { "version", no_argument, NULL, 'V' },
 933                 {}
 934         };
 935         int fd_ctrl = -1;
 936         int fd_netlink = -1;
 937         int fd_worker = -1;
 938         struct epoll_event ep_ctrl, ep_inotify, ep_signal, ep_netlink, ep_worker;
 939         struct udev_ctrl_connection *ctrl_conn = NULL;
 940         int rc = 1;
 941
 942         udev = udev_new();
 943         if (udev == NULL)
 944                 goto exit;
 945
 946         log_set_target(LOG_TARGET_AUTO);
 947         log_parse_environment();
 948         log_open();
 949
 950         udev_set_log_fn(udev, udev_main_log);
 951         log_set_max_level(udev_get_log_priority(udev));
 952
 953         log_debug("version %s", VERSION);
 954         label_init("/dev");
 955
 956         for (;;) {
 957                 int option;
 958
 959                 option = getopt_long(argc, argv, "c:de:DtN:hV", options, NULL);
 960                 if (option == -1)
 961                         break;
 962
 963                 switch (option) {
 964                 case 'd':
 965                         daemonize = true;
 966                         break;
 967                 case 'c':
 968                         children_max = strtoul(optarg, NULL, 0);
 969                         break;
 970                 case 'e':
 971                         exec_delay = strtoul(optarg, NULL, 0);
 972                         break;
 973                 case 'D':
 974                         debug = true;
 975                         log_set_max_level(LOG_DEBUG);
 976                         udev_set_log_priority(udev, LOG_DEBUG);
 977                         break;
 978                 case 'N':
 979                         if (streq(optarg, "early")) {
 980                                 resolve_names = 1;
 981                         } else if (streq(optarg, "late")) {
 982                                 resolve_names = 0;
 983                         } else if (streq(optarg, "never")) {
 984                                 resolve_names = -1;
 985                         } else {
 986                                 fprintf(stderr, "resolve-names must be early, late or never\n");
 987                                 log_error("resolve-names must be early, late or never");
 988                                 goto exit;
 989                         }
 990                         break;
 991                 case 'h':
 992                         printf("Usage: udevd OPTIONS\n"
 993                                "  --daemon\n"
 994                                "  --debug\n"
 995                                "  --children-max=<maximum number of workers>\n"
 996                                "  --exec-delay=<seconds to wait before executing RUN=>\n"
 997                                "  --resolve-names=early|late|never\n"
 998                                "  --version\n"
 999                                "  --help\n"
1000                                "\n");
1001                         goto exit;
1002                 case 'V':
1003                         printf("%s\n", VERSION);
1004                         goto exit;
1005                 default:
1006                         goto exit;
1007                 }
1008         }
1009
1010         kernel_cmdline_options(udev);
1011
1012         if (getuid() != 0) {
1013                 fprintf(stderr, "root privileges required\n");
1014                 log_error("root privileges required");
1015                 goto exit;
1016         }
1017
1018         /* set umask before creating any file/directory */
1019         chdir("/");
1020         umask(022);
1021
1022         mkdir("/run/udev", 0755);
1023
1024         dev_setup(NULL);
1025
1026         /* before opening new files, make sure std{in,out,err} fds are in a sane state */
1027         if (daemonize) {
1028                 int fd;
1029
1030                 fd = open("/dev/null", O_RDWR);
1031                 if (fd >= 0) {
1032                         if (write(STDOUT_FILENO, 0, 0) < 0)
1033                                 dup2(fd, STDOUT_FILENO);
1034                         if (write(STDERR_FILENO, 0, 0) < 0)
1035                                 dup2(fd, STDERR_FILENO);
1036                         if (fd > STDERR_FILENO)
1037                                 close(fd);
1038                 } else {
1039                         fprintf(stderr, "cannot open /dev/null\n");
1040                         log_error("cannot open /dev/null");
1041                 }
1042         }
1043
1044         if (systemd_fds(udev, &fd_ctrl, &fd_netlink) >= 0) {
1045                 /* get control and netlink socket from systemd */
1046                 udev_ctrl = udev_ctrl_new_from_fd(udev, fd_ctrl);
1047                 if (udev_ctrl == NULL) {
1048                         log_error("error taking over udev control socket");
1049                         rc = 1;
1050                         goto exit;
1051                 }
1052
1053                 monitor = udev_monitor_new_from_netlink_fd(udev, "kernel", fd_netlink);
1054                 if (monitor == NULL) {
1055                         log_error("error taking over netlink socket");
1056                         rc = 3;
1057                         goto exit;
1058                 }
1059
1060                 /* get our own cgroup, we regularly kill everything udev has left behind */
1061                 if (cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, 0, &udev_cgroup) < 0)
1062                         udev_cgroup = NULL;
1063         } else {
1064                 /* open control and netlink socket */
1065                 udev_ctrl = udev_ctrl_new(udev);
1066                 if (udev_ctrl == NULL) {
1067                         fprintf(stderr, "error initializing udev control socket");
1068                         log_error("error initializing udev control socket");
1069                         rc = 1;
1070                         goto exit;
1071                 }
1072                 fd_ctrl = udev_ctrl_get_fd(udev_ctrl);
1073
1074                 monitor = udev_monitor_new_from_netlink(udev, "kernel");
1075                 if (monitor == NULL) {
1076                         fprintf(stderr, "error initializing netlink socket\n");
1077                         log_error("error initializing netlink socket");
1078                         rc = 3;
1079                         goto exit;
1080                 }
1081                 fd_netlink = udev_monitor_get_fd(monitor);
1082         }
1083
1084         if (udev_monitor_enable_receiving(monitor) < 0) {
1085                 fprintf(stderr, "error binding netlink socket\n");
1086                 log_error("error binding netlink socket");
1087                 rc = 3;
1088                 goto exit;
1089         }
1090
1091         if (udev_ctrl_enable_receiving(udev_ctrl) < 0) {
1092                 fprintf(stderr, "error binding udev control socket\n");
1093                 log_error("error binding udev control socket");
1094                 rc = 1;
1095                 goto exit;
1096         }
1097
1098         udev_monitor_set_receive_buffer_size(monitor, 128 * 1024 * 1024);
1099
1100         if (daemonize) {
1101                 pid_t pid;
1102
1103                 pid = fork();
1104                 switch (pid) {
1105                 case 0:
1106                         break;
1107                 case -1:
1108                         log_error("fork of daemon failed: %m");
1109                         rc = 4;
1110                         goto exit;
1111                 default:
1112                         rc = EXIT_SUCCESS;
1113                         goto exit_daemonize;
1114                 }
1115
1116                 setsid();
1117
1118                 write_string_file("/proc/self/oom_score_adj", "-1000");
1119         } else {
1120                 sd_notify(1, "READY=1");
1121         }
1122
1123         print_kmsg("starting version " VERSION "\n");
1124
1125         if (!debug) {
1126                 int fd;
1127
1128                 fd = open("/dev/null", O_RDWR);
1129                 if (fd >= 0) {
1130                         dup2(fd, STDIN_FILENO);
1131                         dup2(fd, STDOUT_FILENO);
1132                         dup2(fd, STDERR_FILENO);
1133                         close(fd);
1134                 }
1135         }
1136
1137         fd_inotify = udev_watch_init(udev);
1138         if (fd_inotify < 0) {
1139                 fprintf(stderr, "error initializing inotify\n");
1140                 log_error("error initializing inotify");
1141                 rc = 4;
1142                 goto exit;
1143         }
1144         udev_watch_restore(udev);
1145
1146         /* block and listen to all signals on signalfd */
1147         sigfillset(&mask);
1148         sigprocmask(SIG_SETMASK, &mask, &sigmask_orig);
1149         fd_signal = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
1150         if (fd_signal < 0) {
1151                 fprintf(stderr, "error creating signalfd\n");
1152                 log_error("error creating signalfd");
1153                 rc = 5;
1154                 goto exit;
1155         }
1156
1157         /* unnamed socket from workers to the main daemon */
1158         if (socketpair(AF_LOCAL, SOCK_DGRAM|SOCK_CLOEXEC, 0, worker_watch) < 0) {
1159                 fprintf(stderr, "error creating socketpair\n");
1160                 log_error("error creating socketpair");
1161                 rc = 6;
1162                 goto exit;
1163         }
1164         fd_worker = worker_watch[READ_END];
1165
1166         udev_builtin_init(udev);
1167
1168         rules = udev_rules_new(udev, resolve_names);
1169         if (rules == NULL) {
1170                 log_error("error reading rules");
1171                 goto exit;
1172         }
1173
1174         memzero(&ep_ctrl, sizeof(struct epoll_event));
1175         ep_ctrl.events = EPOLLIN;
1176         ep_ctrl.data.fd = fd_ctrl;
1177
1178         memzero(&ep_inotify, sizeof(struct epoll_event));
1179         ep_inotify.events = EPOLLIN;
1180         ep_inotify.data.fd = fd_inotify;
1181
1182         memzero(&ep_signal, sizeof(struct epoll_event));
1183         ep_signal.events = EPOLLIN;
1184         ep_signal.data.fd = fd_signal;
1185
1186         memzero(&ep_netlink, sizeof(struct epoll_event));
1187         ep_netlink.events = EPOLLIN;
1188         ep_netlink.data.fd = fd_netlink;
1189
1190         memzero(&ep_worker, sizeof(struct epoll_event));
1191         ep_worker.events = EPOLLIN;
1192         ep_worker.data.fd = fd_worker;
1193
1194         fd_ep = epoll_create1(EPOLL_CLOEXEC);
1195         if (fd_ep < 0) {
1196                 log_error("error creating epoll fd: %m");
1197                 goto exit;
1198         }
1199         if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_ctrl, &ep_ctrl) < 0 ||
1200             epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_inotify, &ep_inotify) < 0 ||
1201             epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_signal, &ep_signal) < 0 ||
1202             epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_netlink, &ep_netlink) < 0 ||
1203             epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_worker, &ep_worker) < 0) {
1204                 log_error("fail to add fds to epoll: %m");
1205                 goto exit;
1206         }
1207
1208         if (children_max <= 0) {
1209                 cpu_set_t cpu_set;
1210
1211                 children_max = 8;
1212
1213                 if (sched_getaffinity(0, sizeof (cpu_set), &cpu_set) == 0) {
1214                         children_max +=  CPU_COUNT(&cpu_set) * 2;
1215                 }
1216         }
1217         log_debug("set children_max to %u", children_max);
1218
1219         rc = udev_rules_apply_static_dev_perms(rules);
1220         if (rc < 0)
1221                 log_error("failed to apply permissions on static device nodes - %s", strerror(-rc));
1222
1223         udev_list_node_init(&event_list);
1224         udev_list_node_init(&worker_list);
1225
1226         for (;;) {
1227                 static usec_t last_usec;
1228                 struct epoll_event ev[8];
1229                 int fdcount;
1230                 int timeout;
1231                 bool is_worker, is_signal, is_inotify, is_netlink, is_ctrl;
1232                 int i;
1233
1234                 if (udev_exit) {
1235                         /* close sources of new events and discard buffered events */
1236                         if (fd_ctrl >= 0) {
1237                                 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_ctrl, NULL);
1238                                 fd_ctrl = -1;
1239                         }
1240                         if (monitor != NULL) {
1241                                 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_netlink, NULL);
1242                                 udev_monitor_unref(monitor);
1243                                 monitor = NULL;
1244                         }
1245                         if (fd_inotify >= 0) {
1246                                 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_inotify, NULL);
1247                                 close(fd_inotify);
1248                                 fd_inotify = -1;
1249                         }
1250
1251                         /* discard queued events and kill workers */
1252                         event_queue_cleanup(udev, EVENT_QUEUED);
1253                         worker_kill(udev);
1254
1255                         /* exit after all has cleaned up */
1256                         if (udev_list_node_is_empty(&event_list) && children == 0)
1257                                 break;
1258
1259                         /* timeout at exit for workers to finish */
1260                         timeout = 30 * MSEC_PER_SEC;
1261                 } else if (udev_list_node_is_empty(&event_list) && children == 0) {
1262                         /* we are idle */
1263                         timeout = -1;
1264
1265                         /* cleanup possible left-over processes in our cgroup */
1266                         if (udev_cgroup)
1267                                 cg_kill(SYSTEMD_CGROUP_CONTROLLER, udev_cgroup, SIGKILL, false, true, NULL);
1268                 } else {
1269                         /* kill idle or hanging workers */
1270                         timeout = 3 * MSEC_PER_SEC;
1271                 }
1272
1273                 /* tell settle that we are busy or idle */
1274                 if (!udev_list_node_is_empty(&event_list)) {
1275                         int fd;
1276
1277                         fd = open("/run/udev/queue", O_WRONLY|O_CREAT|O_CLOEXEC|O_TRUNC|O_NOFOLLOW, 0444);
1278                         if (fd >= 0)
1279                                 close(fd);
1280                 } else {
1281                         unlink("/run/udev/queue");
1282                 }
1283
1284                 fdcount = epoll_wait(fd_ep, ev, ELEMENTSOF(ev), timeout);
1285                 if (fdcount < 0)
1286                         continue;
1287
1288                 if (fdcount == 0) {
1289                         struct udev_list_node *loop;
1290
1291                         /* timeout */
1292                         if (udev_exit) {
1293                                 log_error("timeout, giving up waiting for workers to finish");
1294                                 break;
1295                         }
1296
1297                         /* kill idle workers */
1298                         if (udev_list_node_is_empty(&event_list)) {
1299                                 log_debug("cleanup idle workers");
1300                                 worker_kill(udev);
1301                         }
1302
1303                         /* check for hanging events */
1304                         udev_list_node_foreach(loop, &worker_list) {
1305                                 struct worker *worker = node_to_worker(loop);
1306
1307                                 if (worker->state != WORKER_RUNNING)
1308                                         continue;
1309
1310                                 if ((now(CLOCK_MONOTONIC) - worker->event_start_usec) > 30 * USEC_PER_SEC) {
1311                                         log_error("worker [%u] %s timeout; kill it", worker->pid,
1312                                             worker->event ? worker->event->devpath : "<idle>");
1313                                         kill(worker->pid, SIGKILL);
1314                                         worker->state = WORKER_KILLED;
1315
1316                                         /* drop reference taken for state 'running' */
1317                                         worker_unref(worker);
1318                                         if (worker->event) {
1319                                                 log_error("seq %llu '%s' killed", udev_device_get_seqnum(worker->event->dev), worker->event->devpath);
1320                                                 worker->event->exitcode = -64;
1321                                                 event_queue_delete(worker->event);
1322                                                 worker->event = NULL;
1323                                         }
1324                                 }
1325                         }
1326
1327                 }
1328
1329                 is_worker = is_signal = is_inotify = is_netlink = is_ctrl = false;
1330                 for (i = 0; i < fdcount; i++) {
1331                         if (ev[i].data.fd == fd_worker && ev[i].events & EPOLLIN)
1332                                 is_worker = true;
1333                         else if (ev[i].data.fd == fd_netlink && ev[i].events & EPOLLIN)
1334                                 is_netlink = true;
1335                         else if (ev[i].data.fd == fd_signal && ev[i].events & EPOLLIN)
1336                                 is_signal = true;
1337                         else if (ev[i].data.fd == fd_inotify && ev[i].events & EPOLLIN)
1338                                 is_inotify = true;
1339                         else if (ev[i].data.fd == fd_ctrl && ev[i].events & EPOLLIN)
1340                                 is_ctrl = true;
1341                 }
1342
1343                 /* check for changed config, every 3 seconds at most */
1344                 if ((now(CLOCK_MONOTONIC) - last_usec) > 3 * USEC_PER_SEC) {
1345                         if (udev_rules_check_timestamp(rules))
1346                                 reload = true;
1347                         if (udev_builtin_validate(udev))
1348                                 reload = true;
1349
1350                         last_usec = now(CLOCK_MONOTONIC);
1351                 }
1352
1353                 /* reload requested, HUP signal received, rules changed, builtin changed */
1354                 if (reload) {
1355                         worker_kill(udev);
1356                         rules = udev_rules_unref(rules);
1357                         udev_builtin_exit(udev);
1358                         reload = false;
1359                 }
1360
1361                 /* event has finished */
1362                 if (is_worker)
1363                         worker_returned(fd_worker);
1364
1365                 if (is_netlink) {
1366                         struct udev_device *dev;
1367
1368                         dev = udev_monitor_receive_device(monitor);
1369                         if (dev != NULL) {
1370                                 udev_device_set_usec_initialized(dev, now(CLOCK_MONOTONIC));
1371                                 if (event_queue_insert(dev) < 0)
1372                                         udev_device_unref(dev);
1373                         }
1374                 }
1375
1376                 /* start new events */
1377                 if (!udev_list_node_is_empty(&event_list) && !udev_exit && !stop_exec_queue) {
1378                         udev_builtin_init(udev);
1379                         if (rules == NULL)
1380                                 rules = udev_rules_new(udev, resolve_names);
1381                         if (rules != NULL)
1382                                 event_queue_start(udev);
1383                 }
1384
1385                 if (is_signal) {
1386                         struct signalfd_siginfo fdsi;
1387                         ssize_t size;
1388
1389                         size = read(fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
1390                         if (size == sizeof(struct signalfd_siginfo))
1391                                 handle_signal(udev, fdsi.ssi_signo);
1392                 }
1393
1394                 /* we are shutting down, the events below are not handled anymore */
1395                 if (udev_exit)
1396                         continue;
1397
1398                 /* device node watch */
1399                 if (is_inotify)
1400                         handle_inotify(udev);
1401
1402                 /*
1403                  * This needs to be after the inotify handling, to make sure,
1404                  * that the ping is send back after the possibly generated
1405                  * "change" events by the inotify device node watch.
1406                  *
1407                  * A single time we may receive a client connection which we need to
1408                  * keep open to block the client. It will be closed right before we
1409                  * exit.
1410                  */
1411                 if (is_ctrl)
1412                         ctrl_conn = handle_ctrl_msg(udev_ctrl);
1413         }
1414
1415         rc = EXIT_SUCCESS;
1416 exit:
1417         udev_ctrl_cleanup(udev_ctrl);
1418         unlink("/run/udev/queue");
1419 exit_daemonize:
1420         if (fd_ep >= 0)
1421                 close(fd_ep);
1422         worker_list_cleanup(udev);
1423         event_queue_cleanup(udev, EVENT_UNDEF);
1424         udev_rules_unref(rules);
1425         udev_builtin_exit(udev);
1426         if (fd_signal >= 0)
1427                 close(fd_signal);
1428         if (worker_watch[READ_END] >= 0)
1429                 close(worker_watch[READ_END]);
1430         if (worker_watch[WRITE_END] >= 0)
1431                 close(worker_watch[WRITE_END]);
1432         udev_monitor_unref(monitor);
1433         udev_ctrl_connection_unref(ctrl_conn);
1434         udev_ctrl_unref(udev_ctrl);
1435         label_finish();
1436         udev_unref(udev);
1437         log_close();
1438         return rc;
1439 }