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