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