src/udev/udevd.c

   1 /*
   2  * Copyright (C) 2004-2012 Kay Sievers <kay@vrfy.org>
   3  * Copyright (C) 2004 Chris Friesen <chris_friesen@sympatico.ca>
   4  * Copyright (C) 2009 Canonical Ltd.
   5  * Copyright (C) 2009 Scott James Remnant <scott@netsplit.com>
   6  *
   7  * This program is free software: you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation, either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include <stddef.h>
  22 #include <signal.h>
  23 #include <unistd.h>
  24 #include <errno.h>
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <stdbool.h>
  28 #include <string.h>
  29 #include <ctype.h>
  30 #include <fcntl.h>
  31 #include <time.h>
  32 #include <getopt.h>
  33 #include <dirent.h>
  34 #include <sys/file.h>
  35 #include <sys/time.h>
  36 #include <sys/prctl.h>
  37 #include <sys/socket.h>
  38 #include <sys/un.h>
  39 #include <sys/signalfd.h>
  40 #include <sys/epoll.h>
  41 #include <sys/poll.h>
  42 #include <sys/wait.h>
  43 #include <sys/stat.h>
  44 #include <sys/ioctl.h>
  45 #include <sys/inotify.h>
  46 #include <sys/utsname.h>
  47
  48 #include "udev.h"
  49 #include "udev-util.h"
  50 #include "sd-daemon.h"
  51 #include "cgroup-util.h"
  52 #include "dev-setup.h"
  53 #include "fileio.h"
  54
  55 static bool debug;
  56
  57 void udev_main_log(struct udev *udev, int priority,
  58                    const char *file, int line, const char *fn,
  59                    const char *format, va_list args)
  60 {
  61         log_metav(priority, file, line, fn, format, args);
  62 }
  63
  64 static struct udev_rules *rules;
  65 static struct udev_ctrl *udev_ctrl;
  66 static struct udev_monitor *monitor;
  67 static int worker_watch[2] = { -1, -1 };
  68 static int fd_signal = -1;
  69 static int fd_ep = -1;
  70 static int fd_inotify = -1;
  71 static bool stop_exec_queue;
  72 static bool reload;
  73 static int children;
  74 static int children_max;
  75 static int exec_delay;
  76 static sigset_t sigmask_orig;
  77 static UDEV_LIST(event_list);
  78 static UDEV_LIST(worker_list);
  79 static char *udev_cgroup;
  80 static bool udev_exit;
  81
  82 enum event_state {
  83         EVENT_UNDEF,
  84         EVENT_QUEUED,
  85         EVENT_RUNNING,
  86 };
  87
  88 struct event {
  89         struct udev_list_node node;
  90         struct udev *udev;
  91         struct udev_device *dev;
  92         enum event_state state;
  93         int exitcode;
  94         unsigned long long int delaying_seqnum;
  95         unsigned long long int seqnum;
  96         const char *devpath;
  97         size_t devpath_len;
  98         const char *devpath_old;
  99         dev_t devnum;
 100         int ifindex;
 101         bool is_block;
 102 #ifdef HAVE_FIRMWARE
 103         bool nodelay;
 104 #endif
 105 };
 106
 107 static inline struct event *node_to_event(struct udev_list_node *node)
 108 {
 109         return container_of(node, struct event, node);
 110 }
 111
 112 static void event_queue_cleanup(struct udev *udev, enum event_state type);
 113
 114 enum worker_state {
 115         WORKER_UNDEF,
 116         WORKER_RUNNING,
 117         WORKER_IDLE,
 118         WORKER_KILLED,
 119 };
 120
 121 struct worker {
 122         struct udev_list_node node;
 123         struct udev *udev;
 124         int refcount;
 125         pid_t pid;
 126         struct udev_monitor *monitor;
 127         enum worker_state state;
 128         struct event *event;
 129         usec_t event_start_usec;
 130 };
 131
 132 /* passed from worker to main process */
 133 struct worker_message {
 134         pid_t pid;
 135         int exitcode;
 136 };
 137
 138 static inline struct worker *node_to_worker(struct udev_list_node *node)
 139 {
 140         return container_of(node, struct worker, node);
 141 }
 142
 143 static void event_queue_delete(struct event *event)
 144 {
 145         udev_list_node_remove(&event->node);
 146         udev_device_unref(event->dev);
 147         free(event);
 148 }
 149
 150 static struct worker *worker_ref(struct worker *worker)
 151 {
 152         worker->refcount++;
 153         return worker;
 154 }
 155
 156 static void worker_cleanup(struct worker *worker)
 157 {
 158         udev_list_node_remove(&worker->node);
 159         udev_monitor_unref(worker->monitor);
 160         children--;
 161         free(worker);
 162 }
 163
 164 static void worker_unref(struct worker *worker)
 165 {
 166         worker->refcount--;
 167         if (worker->refcount > 0)
 168                 return;
 169         log_debug("worker [%u] cleaned up", worker->pid);
 170         worker_cleanup(worker);
 171 }
 172
 173 static void worker_list_cleanup(struct udev *udev)
 174 {
 175         struct udev_list_node *loop, *tmp;
 176
 177         udev_list_node_foreach_safe(loop, tmp, &worker_list) {
 178                 struct worker *worker = node_to_worker(loop);
 179
 180                 worker_cleanup(worker);
 181         }
 182 }
 183
 184 static void worker_new(struct event *event)
 185 {
 186         struct udev *udev = event->udev;
 187         struct worker *worker;
 188         struct udev_monitor *worker_monitor;
 189         pid_t pid;
 190
 191         /* listen for new events */
 192         worker_monitor = udev_monitor_new_from_netlink(udev, NULL);
 193         if (worker_monitor == NULL)
 194                 return;
 195         /* allow the main daemon netlink address to send devices to the worker */
 196         udev_monitor_allow_unicast_sender(worker_monitor, monitor);
 197         udev_monitor_enable_receiving(worker_monitor);
 198
 199         worker = new0(struct worker, 1);
 200         if (worker == NULL) {
 201                 udev_monitor_unref(worker_monitor);
 202                 return;
 203         }
 204         /* worker + event reference */
 205         worker->refcount = 2;
 206         worker->udev = udev;
 207
 208         pid = fork();
 209         switch (pid) {
 210         case 0: {
 211                 struct udev_device *dev = NULL;
 212                 int fd_monitor;
 213                 struct epoll_event ep_signal, ep_monitor;
 214                 sigset_t mask;
 215                 int rc = EXIT_SUCCESS;
 216
 217                 /* take initial device from queue */
 218                 dev = event->dev;
 219                 event->dev = NULL;
 220
 221                 free(worker);
 222                 worker_list_cleanup(udev);
 223                 event_queue_cleanup(udev, EVENT_UNDEF);
 224                 udev_monitor_unref(monitor);
 225                 udev_ctrl_unref(udev_ctrl);
 226                 close(fd_signal);
 227                 close(fd_ep);
 228                 close(worker_watch[READ_END]);
 229
 230                 sigfillset(&mask);
 231                 fd_signal = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
 232                 if (fd_signal < 0) {
 233                         log_error("error creating signalfd %m");
 234                         rc = 2;
 235                         goto out;
 236                 }
 237
 238                 fd_ep = epoll_create1(EPOLL_CLOEXEC);
 239                 if (fd_ep < 0) {
 240                         log_error("error creating epoll fd: %m");
 241                         rc = 3;
 242                         goto out;
 243                 }
 244
 245                 memzero(&ep_signal, sizeof(struct epoll_event));
 246                 ep_signal.events = EPOLLIN;
 247                 ep_signal.data.fd = fd_signal;
 248
 249                 fd_monitor = udev_monitor_get_fd(worker_monitor);
 250                 memzero(&ep_monitor, sizeof(struct epoll_event));
 251                 ep_monitor.events = EPOLLIN;
 252                 ep_monitor.data.fd = fd_monitor;
 253
 254                 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_signal, &ep_signal) < 0 ||
 255                     epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_monitor, &ep_monitor) < 0) {
 256                         log_error("fail to add fds to epoll: %m");
 257                         rc = 4;
 258                         goto out;
 259                 }
 260
 261                 /* request TERM signal if parent exits */
 262                 prctl(PR_SET_PDEATHSIG, SIGTERM);
 263
 264                 /* reset OOM score, we only protect the main daemon */
 265                 write_string_file("/proc/self/oom_score_adj", "0");
 266
 267                 for (;;) {
 268                         struct udev_event *udev_event;
 269                         struct worker_message msg;
 270                         int fd_lock = -1;
 271                         int err = 0;
 272
 273                         log_debug("seq %llu running", udev_device_get_seqnum(dev));
 274                         udev_event = udev_event_new(dev);
 275                         if (udev_event == NULL) {
 276                                 rc = 5;
 277                                 goto out;
 278                         }
 279
 280                         /* needed for SIGCHLD/SIGTERM in spawn() */
 281                         udev_event->fd_signal = fd_signal;
 282
 283                         if (exec_delay > 0)
 284                                 udev_event->exec_delay = exec_delay;
 285
 286                         /*
 287                          * Take a "read lock" on the device node; this establishes
 288                          * a concept of device "ownership" to serialize device
 289                          * access. External processes holding a "write lock" will
 290                          * cause udev to skip the event handling; in the case udev
 291                          * acquired the lock, the external process will block until
 292                          * udev has finished its event handling.
 293                          */
 294
 295                         /*
 296                          * <kabi_> since we make check - device seems unused - we try
 297                          *         ioctl to deactivate - and device is found to be opened
 298                          * <kay> sure, you try to take a write lock
 299                          * <kay> if you get it udev is out
 300                          * <kay> if you can't get it, udev is busy
 301                          * <kabi_> we cannot deactivate openned device  (as it is in-use)
 302                          * <kay> maybe we should just exclude dm from that thing entirely
 303                          * <kabi_> IMHO this sounds like a good plan for this moment
 304                          */
 305                         if (streq_ptr("block", udev_device_get_subsystem(dev)) &&
 306                             !startswith("dm-", udev_device_get_sysname(dev))) {
 307                                 struct udev_device *d = dev;
 308
 309                                 if (streq_ptr("partition", udev_device_get_devtype(d)))
 310                                         d = udev_device_get_parent(d);
 311
 312                                 if (d) {
 313                                         fd_lock = open(udev_device_get_devnode(d), O_RDONLY|O_CLOEXEC|O_NOFOLLOW|O_NONBLOCK);
 314                                         if (fd_lock >= 0 && flock(fd_lock, LOCK_SH|LOCK_NB) < 0) {
 315                                                 log_debug("Unable to flock(%s), skipping event handling: %m", udev_device_get_devnode(d));
 316                                                 err = -EWOULDBLOCK;
 317                                                 fd_lock = safe_close(fd_lock);
 318                                                 goto skip;
 319                                         }
 320                                 }
 321                         }
 322
 323                         /* apply rules, create node, symlinks */
 324                         udev_event_execute_rules(udev_event, rules, &sigmask_orig);
 325
 326                         udev_event_execute_run(udev_event, &sigmask_orig);
 327
 328                         /* apply/restore inotify watch */
 329                         if (udev_event->inotify_watch) {
 330                                 udev_watch_begin(udev, dev);
 331                                 udev_device_update_db(dev);
 332                         }
 333
 334                         safe_close(fd_lock);
 335
 336                         /* send processed event back to libudev listeners */
 337                         udev_monitor_send_device(worker_monitor, NULL, dev);
 338
 339 skip:
 340                         /* send udevd the result of the event execution */
 341                         memzero(&msg, sizeof(struct worker_message));
 342                         msg.exitcode = err;
 343                         msg.pid = getpid();
 344                         send(worker_watch[WRITE_END], &msg, sizeof(struct worker_message), 0);
 345
 346                         log_debug("seq %llu processed with %i", udev_device_get_seqnum(dev), err);
 347
 348                         udev_device_unref(dev);
 349                         dev = NULL;
 350
 351                         if (udev_event->sigterm) {
 352                                 udev_event_unref(udev_event);
 353                                 goto out;
 354                         }
 355
 356                         udev_event_unref(udev_event);
 357
 358                         /* wait for more device messages from main udevd, or term signal */
 359                         while (dev == NULL) {
 360                                 struct epoll_event ev[4];
 361                                 int fdcount;
 362                                 int i;
 363
 364                                 fdcount = epoll_wait(fd_ep, ev, ELEMENTSOF(ev), -1);
 365                                 if (fdcount < 0) {
 366                                         if (errno == EINTR)
 367                                                 continue;
 368                                         log_error("failed to poll: %m");
 369                                         goto out;
 370                                 }
 371
 372                                 for (i = 0; i < fdcount; i++) {
 373                                         if (ev[i].data.fd == fd_monitor && ev[i].events & EPOLLIN) {
 374                                                 dev = udev_monitor_receive_device(worker_monitor);
 375                                                 break;
 376                                         } else if (ev[i].data.fd == fd_signal && ev[i].events & EPOLLIN) {
 377                                                 struct signalfd_siginfo fdsi;
 378                                                 ssize_t size;
 379
 380                                                 size = read(fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
 381                                                 if (size != sizeof(struct signalfd_siginfo))
 382                                                         continue;
 383                                                 switch (fdsi.ssi_signo) {
 384                                                 case SIGTERM:
 385                                                         goto out;
 386                                                 }
 387                                         }
 388                                 }
 389                         }
 390                 }
 391 out:
 392                 udev_device_unref(dev);
 393                 safe_close(fd_signal);
 394                 safe_close(fd_ep);
 395                 close(fd_inotify);
 396                 close(worker_watch[WRITE_END]);
 397                 udev_rules_unref(rules);
 398                 udev_builtin_exit(udev);
 399                 udev_monitor_unref(worker_monitor);
 400                 udev_unref(udev);
 401                 log_close();
 402                 exit(rc);
 403         }
 404         case -1:
 405                 udev_monitor_unref(worker_monitor);
 406                 event->state = EVENT_QUEUED;
 407                 free(worker);
 408                 log_error("fork of child failed: %m");
 409                 break;
 410         default:
 411                 /* close monitor, but keep address around */
 412                 udev_monitor_disconnect(worker_monitor);
 413                 worker->monitor = worker_monitor;
 414                 worker->pid = pid;
 415                 worker->state = WORKER_RUNNING;
 416                 worker->event_start_usec = now(CLOCK_MONOTONIC);
 417                 worker->event = event;
 418                 event->state = EVENT_RUNNING;
 419                 udev_list_node_append(&worker->node, &worker_list);
 420                 children++;
 421                 log_debug("seq %llu forked new worker [%u]", udev_device_get_seqnum(event->dev), pid);
 422                 break;
 423         }
 424 }
 425
 426 static void event_run(struct event *event)
 427 {
 428         struct udev_list_node *loop;
 429
 430         udev_list_node_foreach(loop, &worker_list) {
 431                 struct worker *worker = node_to_worker(loop);
 432                 ssize_t count;
 433
 434                 if (worker->state != WORKER_IDLE)
 435                         continue;
 436
 437                 count = udev_monitor_send_device(monitor, worker->monitor, event->dev);
 438                 if (count < 0) {
 439                         log_error("worker [%u] did not accept message %zi (%m), kill it", worker->pid, count);
 440                         kill(worker->pid, SIGKILL);
 441                         worker->state = WORKER_KILLED;
 442                         continue;
 443                 }
 444                 worker_ref(worker);
 445                 worker->event = event;
 446                 worker->state = WORKER_RUNNING;
 447                 worker->event_start_usec = now(CLOCK_MONOTONIC);
 448                 event->state = EVENT_RUNNING;
 449                 return;
 450         }
 451
 452         if (children >= children_max) {
 453                 if (children_max > 1)
 454                         log_debug("maximum number (%i) of children reached", children);
 455                 return;
 456         }
 457
 458         /* start new worker and pass initial device */
 459         worker_new(event);
 460 }
 461
 462 static int event_queue_insert(struct udev_device *dev)
 463 {
 464         struct event *event;
 465
 466         event = new0(struct event, 1);
 467         if (event == NULL)
 468                 return -1;
 469
 470         event->udev = udev_device_get_udev(dev);
 471         event->dev = dev;
 472         event->seqnum = udev_device_get_seqnum(dev);
 473         event->devpath = udev_device_get_devpath(dev);
 474         event->devpath_len = strlen(event->devpath);
 475         event->devpath_old = udev_device_get_devpath_old(dev);
 476         event->devnum = udev_device_get_devnum(dev);
 477         event->is_block = streq("block", udev_device_get_subsystem(dev));
 478         event->ifindex = udev_device_get_ifindex(dev);
 479 #ifdef HAVE_FIRMWARE
 480         if (streq(udev_device_get_subsystem(dev), "firmware"))
 481                 event->nodelay = true;
 482 #endif
 483
 484         log_debug("seq %llu queued, '%s' '%s'", udev_device_get_seqnum(dev),
 485              udev_device_get_action(dev), udev_device_get_subsystem(dev));
 486
 487         event->state = EVENT_QUEUED;
 488         udev_list_node_append(&event->node, &event_list);
 489         return 0;
 490 }
 491
 492 static void worker_kill(struct udev *udev)
 493 {
 494         struct udev_list_node *loop;
 495
 496         udev_list_node_foreach(loop, &worker_list) {
 497                 struct worker *worker = node_to_worker(loop);
 498
 499                 if (worker->state == WORKER_KILLED)
 500                         continue;
 501
 502                 worker->state = WORKER_KILLED;
 503                 kill(worker->pid, SIGTERM);
 504         }
 505 }
 506
 507 /* lookup event for identical, parent, child device */
 508 static bool is_devpath_busy(struct event *event)
 509 {
 510         struct udev_list_node *loop;
 511         size_t common;
 512
 513         /* check if queue contains events we depend on */
 514         udev_list_node_foreach(loop, &event_list) {
 515                 struct event *loop_event = node_to_event(loop);
 516
 517                 /* we already found a later event, earlier can not block us, no need to check again */
 518                 if (loop_event->seqnum < event->delaying_seqnum)
 519                         continue;
 520
 521                 /* event we checked earlier still exists, no need to check again */
 522                 if (loop_event->seqnum == event->delaying_seqnum)
 523                         return true;
 524
 525                 /* found ourself, no later event can block us */
 526                 if (loop_event->seqnum >= event->seqnum)
 527                         break;
 528
 529                 /* check major/minor */
 530                 if (major(event->devnum) != 0 && event->devnum == loop_event->devnum && event->is_block == loop_event->is_block)
 531                         return true;
 532
 533                 /* check network device ifindex */
 534                 if (event->ifindex != 0 && event->ifindex == loop_event->ifindex)
 535                         return true;
 536
 537                 /* check our old name */
 538                 if (event->devpath_old != NULL && streq(loop_event->devpath, event->devpath_old)) {
 539                         event->delaying_seqnum = loop_event->seqnum;
 540                         return true;
 541                 }
 542
 543                 /* compare devpath */
 544                 common = MIN(loop_event->devpath_len, event->devpath_len);
 545
 546                 /* one devpath is contained in the other? */
 547                 if (memcmp(loop_event->devpath, event->devpath, common) != 0)
 548                         continue;
 549
 550                 /* identical device event found */
 551                 if (loop_event->devpath_len == event->devpath_len) {
 552                         /* devices names might have changed/swapped in the meantime */
 553                         if (major(event->devnum) != 0 && (event->devnum != loop_event->devnum || event->is_block != loop_event->is_block))
 554                                 continue;
 555                         if (event->ifindex != 0 && event->ifindex != loop_event->ifindex)
 556                                 continue;
 557                         event->delaying_seqnum = loop_event->seqnum;
 558                         return true;
 559                 }
 560
 561 #ifdef HAVE_FIRMWARE
 562                 /* allow to bypass the dependency tracking */
 563                 if (event->nodelay)
 564                         continue;
 565 #endif
 566
 567                 /* parent device event found */
 568                 if (event->devpath[common] == '/') {
 569                         event->delaying_seqnum = loop_event->seqnum;
 570                         return true;
 571                 }
 572
 573                 /* child device event found */
 574                 if (loop_event->devpath[common] == '/') {
 575                         event->delaying_seqnum = loop_event->seqnum;
 576                         return true;
 577                 }
 578
 579                 /* no matching device */
 580                 continue;
 581         }
 582
 583         return false;
 584 }
 585
 586 static void event_queue_start(struct udev *udev)
 587 {
 588         struct udev_list_node *loop;
 589
 590         udev_list_node_foreach(loop, &event_list) {
 591                 struct event *event = node_to_event(loop);
 592
 593                 if (event->state != EVENT_QUEUED)
 594                         continue;
 595
 596                 /* do not start event if parent or child event is still running */
 597                 if (is_devpath_busy(event))
 598                         continue;
 599
 600                 event_run(event);
 601         }
 602 }
 603
 604 static void event_queue_cleanup(struct udev *udev, enum event_state match_type)
 605 {
 606         struct udev_list_node *loop, *tmp;
 607
 608         udev_list_node_foreach_safe(loop, tmp, &event_list) {
 609                 struct event *event = node_to_event(loop);
 610
 611                 if (match_type != EVENT_UNDEF && match_type != event->state)
 612                         continue;
 613
 614                 event_queue_delete(event);
 615         }
 616 }
 617
 618 static void worker_returned(int fd_worker)
 619 {
 620         for (;;) {
 621                 struct worker_message msg;
 622                 ssize_t size;
 623                 struct udev_list_node *loop;
 624
 625                 size = recv(fd_worker, &msg, sizeof(struct worker_message), MSG_DONTWAIT);
 626                 if (size != sizeof(struct worker_message))
 627                         break;
 628
 629                 /* lookup worker who sent the signal */
 630                 udev_list_node_foreach(loop, &worker_list) {
 631                         struct worker *worker = node_to_worker(loop);
 632
 633                         if (worker->pid != msg.pid)
 634                                 continue;
 635
 636                         /* worker returned */
 637                         if (worker->event) {
 638                                 worker->event->exitcode = msg.exitcode;
 639                                 event_queue_delete(worker->event);
 640                                 worker->event = NULL;
 641                         }
 642                         if (worker->state != WORKER_KILLED)
 643                                 worker->state = WORKER_IDLE;
 644                         worker_unref(worker);
 645                         break;
 646                 }
 647         }
 648 }
 649
 650 /* receive the udevd message from userspace */
 651 static struct udev_ctrl_connection *handle_ctrl_msg(struct udev_ctrl *uctrl)
 652 {
 653         struct udev *udev = udev_ctrl_get_udev(uctrl);
 654         struct udev_ctrl_connection *ctrl_conn;
 655         struct udev_ctrl_msg *ctrl_msg = NULL;
 656         const char *str;
 657         int i;
 658
 659         ctrl_conn = udev_ctrl_get_connection(uctrl);
 660         if (ctrl_conn == NULL)
 661                 goto out;
 662
 663         ctrl_msg = udev_ctrl_receive_msg(ctrl_conn);
 664         if (ctrl_msg == NULL)
 665                 goto out;
 666
 667         i = udev_ctrl_get_set_log_level(ctrl_msg);
 668         if (i >= 0) {
 669                 log_debug("udevd message (SET_LOG_LEVEL) received, log_priority=%i", i);
 670                 log_set_max_level(i);
 671                 udev_set_log_priority(udev, i);
 672                 worker_kill(udev);
 673         }
 674
 675         if (udev_ctrl_get_stop_exec_queue(ctrl_msg) > 0) {
 676                 log_debug("udevd message (STOP_EXEC_QUEUE) received");
 677                 stop_exec_queue = true;
 678         }
 679
 680         if (udev_ctrl_get_start_exec_queue(ctrl_msg) > 0) {
 681                 log_debug("udevd message (START_EXEC_QUEUE) received");
 682                 stop_exec_queue = false;
 683         }
 684
 685         if (udev_ctrl_get_reload(ctrl_msg) > 0) {
 686                 log_debug("udevd message (RELOAD) received");
 687                 reload = true;
 688         }
 689
 690         str = udev_ctrl_get_set_env(ctrl_msg);
 691         if (str != NULL) {
 692                 char *key;
 693
 694                 key = strdup(str);
 695                 if (key != NULL) {
 696                         char *val;
 697
 698                         val = strchr(key, '=');
 699                         if (val != NULL) {
 700                                 val[0] = '\0';
 701                                 val = &val[1];
 702                                 if (val[0] == '\0') {
 703                                         log_debug("udevd message (ENV) received, unset '%s'", key);
 704                                         udev_add_property(udev, key, NULL);
 705                                 } else {
 706                                         log_debug("udevd message (ENV) received, set '%s=%s'", key, val);
 707                                         udev_add_property(udev, key, val);
 708                                 }
 709                         } else {
 710                                 log_error("wrong key format '%s'", key);
 711                         }
 712                         free(key);
 713                 }
 714                 worker_kill(udev);
 715         }
 716
 717         i = udev_ctrl_get_set_children_max(ctrl_msg);
 718         if (i >= 0) {
 719                 log_debug("udevd message (SET_MAX_CHILDREN) received, children_max=%i", i);
 720                 children_max = i;
 721         }
 722
 723         if (udev_ctrl_get_ping(ctrl_msg) > 0)
 724                 log_debug("udevd message (SYNC) received");
 725
 726         if (udev_ctrl_get_exit(ctrl_msg) > 0) {
 727                 log_debug("udevd message (EXIT) received");
 728                 udev_exit = true;
 729                 /* keep reference to block the client until we exit */
 730                 udev_ctrl_connection_ref(ctrl_conn);
 731         }
 732 out:
 733         udev_ctrl_msg_unref(ctrl_msg);
 734         return udev_ctrl_connection_unref(ctrl_conn);
 735 }
 736
 737 static int synthesize_change(struct udev_device *dev) {
 738         char filename[UTIL_PATH_SIZE];
 739         int r;
 740
 741         log_debug("device %s closed, synthesising 'change'", udev_device_get_devnode(dev));
 742         strscpyl(filename, sizeof(filename), udev_device_get_syspath(dev), "/uevent", NULL);
 743         write_string_file(filename, "change");
 744
 745         /* for disks devices, re-trigger all partitions too */
 746         if (streq_ptr("block", udev_device_get_subsystem(dev)) &&
 747             streq_ptr("disk", udev_device_get_devtype(dev))) {
 748                 struct udev *udev = udev_device_get_udev(dev);
 749                 _cleanup_udev_enumerate_unref_ struct udev_enumerate *e = NULL;
 750                 struct udev_list_entry *item;
 751
 752                 e = udev_enumerate_new(udev);
 753                 if (!e)
 754                         return -ENOMEM;
 755
 756                 r = udev_enumerate_add_match_parent(e, dev);
 757                 if (r < 0)
 758                         return r;
 759
 760                 r = udev_enumerate_add_match_subsystem(e, "block");
 761                 if (r < 0)
 762                         return r;
 763
 764                 r = udev_enumerate_scan_devices(e);
 765                 udev_list_entry_foreach(item, udev_enumerate_get_list_entry(e)) {
 766                         _cleanup_udev_device_unref_ struct udev_device *d = NULL;
 767
 768                         d = udev_device_new_from_syspath(udev, udev_list_entry_get_name(item));
 769                         if (!d)
 770                                 continue;
 771
 772                         if (!streq_ptr("partition", udev_device_get_devtype(d)))
 773                                 continue;
 774
 775                         log_debug("device %s closed, synthesising partition '%s' 'change'",
 776                                   udev_device_get_devnode(dev), udev_device_get_devnode(d));
 777                         strscpyl(filename, sizeof(filename), udev_device_get_syspath(d), "/uevent", NULL);
 778                         write_string_file(filename, "change");
 779                 }
 780         }
 781
 782         return 0;
 783 }
 784
 785 static int handle_inotify(struct udev *udev)
 786 {
 787         int nbytes, pos;
 788         char *buf;
 789         struct inotify_event *ev;
 790         int r;
 791
 792         r = ioctl(fd_inotify, FIONREAD, &nbytes);
 793         if (r < 0 || nbytes <= 0)
 794                 return -errno;
 795
 796         buf = malloc(nbytes);
 797         if (!buf) {
 798                 log_error("error getting buffer for inotify");
 799                 return -ENOMEM;
 800         }
 801
 802         nbytes = read(fd_inotify, buf, nbytes);
 803
 804         for (pos = 0; pos < nbytes; pos += sizeof(struct inotify_event) + ev->len) {
 805                 struct udev_device *dev;
 806
 807                 ev = (struct inotify_event *)(buf + pos);
 808                 dev = udev_watch_lookup(udev, ev->wd);
 809                 if (!dev)
 810                         continue;
 811
 812                 log_debug("inotify event: %x for %s", ev->mask, udev_device_get_devnode(dev));
 813                 if (ev->mask & IN_CLOSE_WRITE)
 814                         synthesize_change(dev);
 815                 else if (ev->mask & IN_IGNORED)
 816                         udev_watch_end(udev, dev);
 817
 818                 udev_device_unref(dev);
 819         }
 820
 821         free(buf);
 822         return 0;
 823 }
 824
 825 static void handle_signal(struct udev *udev, int signo)
 826 {
 827         switch (signo) {
 828         case SIGINT:
 829         case SIGTERM:
 830                 udev_exit = true;
 831                 break;
 832         case SIGCHLD:
 833                 for (;;) {
 834                         pid_t pid;
 835                         int status;
 836                         struct udev_list_node *loop, *tmp;
 837
 838                         pid = waitpid(-1, &status, WNOHANG);
 839                         if (pid <= 0)
 840                                 break;
 841
 842                         udev_list_node_foreach_safe(loop, tmp, &worker_list) {
 843                                 struct worker *worker = node_to_worker(loop);
 844
 845                                 if (worker->pid != pid)
 846                                         continue;
 847                                 log_debug("worker [%u] exit", pid);
 848
 849                                 if (WIFEXITED(status)) {
 850                                         if (WEXITSTATUS(status) != 0)
 851                                                 log_error("worker [%u] exit with return code %i",
 852                                                           pid, WEXITSTATUS(status));
 853                                 } else if (WIFSIGNALED(status)) {
 854                                         log_error("worker [%u] terminated by signal %i (%s)",
 855                                                   pid, WTERMSIG(status), strsignal(WTERMSIG(status)));
 856                                 } else if (WIFSTOPPED(status)) {
 857                                         log_error("worker [%u] stopped", pid);
 858                                 } else if (WIFCONTINUED(status)) {
 859                                         log_error("worker [%u] continued", pid);
 860                                 } else {
 861                                         log_error("worker [%u] exit with status 0x%04x", pid, status);
 862                                 }
 863
 864                                 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
 865                                         if (worker->event) {
 866                                                 log_error("worker [%u] failed while handling '%s'",
 867                                                           pid, worker->event->devpath);
 868                                                 worker->event->exitcode = -32;
 869                                                 event_queue_delete(worker->event);
 870
 871                                                 /* drop reference taken for state 'running' */
 872                                                 worker_unref(worker);
 873                                         }
 874                                 }
 875                                 worker_unref(worker);
 876                                 break;
 877                         }
 878                 }
 879                 break;
 880         case SIGHUP:
 881                 reload = true;
 882                 break;
 883         }
 884 }
 885
 886 static int systemd_fds(struct udev *udev, int *rctrl, int *rnetlink)
 887 {
 888         int ctrl = -1, netlink = -1;
 889         int fd, n;
 890
 891         n = sd_listen_fds(true);
 892         if (n <= 0)
 893                 return -1;
 894
 895         for (fd = SD_LISTEN_FDS_START; fd < n + SD_LISTEN_FDS_START; fd++) {
 896                 if (sd_is_socket(fd, AF_LOCAL, SOCK_SEQPACKET, -1)) {
 897                         if (ctrl >= 0)
 898                                 return -1;
 899                         ctrl = fd;
 900                         continue;
 901                 }
 902
 903                 if (sd_is_socket(fd, AF_NETLINK, SOCK_RAW, -1)) {
 904                         if (netlink >= 0)
 905                                 return -1;
 906                         netlink = fd;
 907                         continue;
 908                 }
 909
 910                 return -1;
 911         }
 912
 913         if (ctrl < 0 || netlink < 0)
 914                 return -1;
 915
 916         log_debug("ctrl=%i netlink=%i", ctrl, netlink);
 917         *rctrl = ctrl;
 918         *rnetlink = netlink;
 919         return 0;
 920 }
 921
 922 /*
 923  * read the kernel commandline, in case we need to get into debug mode
 924  *   udev.log-priority=<level>              syslog priority
 925  *   udev.children-max=<number of workers>  events are fully serialized if set to 1
 926  *   udev.exec-delay=<number of seconds>    delay execution of every executed program
 927  */
 928 static void kernel_cmdline_options(struct udev *udev)
 929 {
 930         _cleanup_free_ char *line = NULL;
 931         char *w, *state;
 932         size_t l;
 933         int r;
 934
 935         r = proc_cmdline(&line);
 936         if (r < 0)
 937                 log_warning("Failed to read /proc/cmdline, ignoring: %s", strerror(-r));
 938         if (r <= 0)
 939                 return;
 940
 941         FOREACH_WORD_QUOTED(w, l, line, state) {
 942                 char *s, *opt;
 943
 944                 s = strndup(w, l);
 945                 if (!s)
 946                         break;
 947
 948                 /* accept the same options for the initrd, prefixed with "rd." */
 949                 if (in_initrd() && startswith(s, "rd."))
 950                         opt = s + 3;
 951                 else
 952                         opt = s;
 953
 954                 if (startswith(opt, "udev.log-priority=")) {
 955                         int prio;
 956
 957                         prio = util_log_priority(opt + 18);
 958                         log_set_max_level(prio);
 959                         udev_set_log_priority(udev, prio);
 960                 } else if (startswith(opt, "udev.children-max=")) {
 961                         children_max = strtoul(opt + 18, NULL, 0);
 962                 } else if (startswith(opt, "udev.exec-delay=")) {
 963                         exec_delay = strtoul(opt + 16, NULL, 0);
 964                 }
 965
 966                 free(s);
 967         }
 968 }
 969
 970 int main(int argc, char *argv[])
 971 {
 972         struct udev *udev;
 973         sigset_t mask;
 974         int daemonize = false;
 975         int resolve_names = 1;
 976         static const struct option options[] = {
 977                 { "daemon", no_argument, NULL, 'd' },
 978                 { "debug", no_argument, NULL, 'D' },
 979                 { "children-max", required_argument, NULL, 'c' },
 980                 { "exec-delay", required_argument, NULL, 'e' },
 981                 { "resolve-names", required_argument, NULL, 'N' },
 982                 { "help", no_argument, NULL, 'h' },
 983                 { "version", no_argument, NULL, 'V' },
 984                 {}
 985         };
 986         int fd_ctrl = -1;
 987         int fd_netlink = -1;
 988         int fd_worker = -1;
 989         struct epoll_event ep_ctrl, ep_inotify, ep_signal, ep_netlink, ep_worker;
 990         struct udev_ctrl_connection *ctrl_conn = NULL;
 991         int rc = 1;
 992
 993         udev = udev_new();
 994         if (udev == NULL)
 995                 goto exit;
 996
 997         log_set_target(LOG_TARGET_AUTO);
 998         log_parse_environment();
 999         log_open();
1000
1001         udev_set_log_fn(udev, udev_main_log);
1002         log_set_max_level(udev_get_log_priority(udev));
1003
1004         log_debug("version %s", VERSION);
1005         label_init("/dev");
1006
1007         for (;;) {
1008                 int option;
1009
1010                 option = getopt_long(argc, argv, "c:de:DtN:hV", options, NULL);
1011                 if (option == -1)
1012                         break;
1013
1014                 switch (option) {
1015                 case 'd':
1016                         daemonize = true;
1017                         break;
1018                 case 'c':
1019                         children_max = strtoul(optarg, NULL, 0);
1020                         break;
1021                 case 'e':
1022                         exec_delay = strtoul(optarg, NULL, 0);
1023                         break;
1024                 case 'D':
1025                         debug = true;
1026                         log_set_max_level(LOG_DEBUG);
1027                         udev_set_log_priority(udev, LOG_DEBUG);
1028                         break;
1029                 case 'N':
1030                         if (streq(optarg, "early")) {
1031                                 resolve_names = 1;
1032                         } else if (streq(optarg, "late")) {
1033                                 resolve_names = 0;
1034                         } else if (streq(optarg, "never")) {
1035                                 resolve_names = -1;
1036                         } else {
1037                                 fprintf(stderr, "resolve-names must be early, late or never\n");
1038                                 log_error("resolve-names must be early, late or never");
1039                                 goto exit;
1040                         }
1041                         break;
1042                 case 'h':
1043                         printf("Usage: udevd OPTIONS\n"
1044                                "  --daemon\n"
1045                                "  --debug\n"
1046                                "  --children-max=<maximum number of workers>\n"
1047                                "  --exec-delay=<seconds to wait before executing RUN=>\n"
1048                                "  --resolve-names=early|late|never\n"
1049                                "  --version\n"
1050                                "  --help\n"
1051                                "\n");
1052                         goto exit;
1053                 case 'V':
1054                         printf("%s\n", VERSION);
1055                         goto exit;
1056                 default:
1057                         goto exit;
1058                 }
1059         }
1060
1061         kernel_cmdline_options(udev);
1062
1063         if (getuid() != 0) {
1064                 fprintf(stderr, "root privileges required\n");
1065                 log_error("root privileges required");
1066                 goto exit;
1067         }
1068
1069         /* set umask before creating any file/directory */
1070         chdir("/");
1071         umask(022);
1072
1073         mkdir("/run/udev", 0755);
1074
1075         dev_setup(NULL);
1076
1077         /* before opening new files, make sure std{in,out,err} fds are in a sane state */
1078         if (daemonize) {
1079                 int fd;
1080
1081                 fd = open("/dev/null", O_RDWR);
1082                 if (fd >= 0) {
1083                         if (write(STDOUT_FILENO, 0, 0) < 0)
1084                                 dup2(fd, STDOUT_FILENO);
1085                         if (write(STDERR_FILENO, 0, 0) < 0)
1086                                 dup2(fd, STDERR_FILENO);
1087                         if (fd > STDERR_FILENO)
1088                                 close(fd);
1089                 } else {
1090                         fprintf(stderr, "cannot open /dev/null\n");
1091                         log_error("cannot open /dev/null");
1092                 }
1093         }
1094
1095         if (systemd_fds(udev, &fd_ctrl, &fd_netlink) >= 0) {
1096                 /* get control and netlink socket from systemd */
1097                 udev_ctrl = udev_ctrl_new_from_fd(udev, fd_ctrl);
1098                 if (udev_ctrl == NULL) {
1099                         log_error("error taking over udev control socket");
1100                         rc = 1;
1101                         goto exit;
1102                 }
1103
1104                 monitor = udev_monitor_new_from_netlink_fd(udev, "kernel", fd_netlink);
1105                 if (monitor == NULL) {
1106                         log_error("error taking over netlink socket");
1107                         rc = 3;
1108                         goto exit;
1109                 }
1110
1111                 /* get our own cgroup, we regularly kill everything udev has left behind */
1112                 if (cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, 0, &udev_cgroup) < 0)
1113                         udev_cgroup = NULL;
1114         } else {
1115                 /* open control and netlink socket */
1116                 udev_ctrl = udev_ctrl_new(udev);
1117                 if (udev_ctrl == NULL) {
1118                         fprintf(stderr, "error initializing udev control socket");
1119                         log_error("error initializing udev control socket");
1120                         rc = 1;
1121                         goto exit;
1122                 }
1123                 fd_ctrl = udev_ctrl_get_fd(udev_ctrl);
1124
1125                 monitor = udev_monitor_new_from_netlink(udev, "kernel");
1126                 if (monitor == NULL) {
1127                         fprintf(stderr, "error initializing netlink socket\n");
1128                         log_error("error initializing netlink socket");
1129                         rc = 3;
1130                         goto exit;
1131                 }
1132                 fd_netlink = udev_monitor_get_fd(monitor);
1133         }
1134
1135         if (udev_monitor_enable_receiving(monitor) < 0) {
1136                 fprintf(stderr, "error binding netlink socket\n");
1137                 log_error("error binding netlink socket");
1138                 rc = 3;
1139                 goto exit;
1140         }
1141
1142         if (udev_ctrl_enable_receiving(udev_ctrl) < 0) {
1143                 fprintf(stderr, "error binding udev control socket\n");
1144                 log_error("error binding udev control socket");
1145                 rc = 1;
1146                 goto exit;
1147         }
1148
1149         udev_monitor_set_receive_buffer_size(monitor, 128 * 1024 * 1024);
1150
1151         if (daemonize) {
1152                 pid_t pid;
1153
1154                 pid = fork();
1155                 switch (pid) {
1156                 case 0:
1157                         break;
1158                 case -1:
1159                         log_error("fork of daemon failed: %m");
1160                         rc = 4;
1161                         goto exit;
1162                 default:
1163                         rc = EXIT_SUCCESS;
1164                         goto exit_daemonize;
1165                 }
1166
1167                 setsid();
1168
1169                 write_string_file("/proc/self/oom_score_adj", "-1000");
1170         } else {
1171                 sd_notify(1, "READY=1");
1172         }
1173
1174         print_kmsg("starting version " VERSION "\n");
1175
1176         if (!debug) {
1177                 int fd;
1178
1179                 fd = open("/dev/null", O_RDWR);
1180                 if (fd >= 0) {
1181                         dup2(fd, STDIN_FILENO);
1182                         dup2(fd, STDOUT_FILENO);
1183                         dup2(fd, STDERR_FILENO);
1184                         close(fd);
1185                 }
1186         }
1187
1188         fd_inotify = udev_watch_init(udev);
1189         if (fd_inotify < 0) {
1190                 fprintf(stderr, "error initializing inotify\n");
1191                 log_error("error initializing inotify");
1192                 rc = 4;
1193                 goto exit;
1194         }
1195         udev_watch_restore(udev);
1196
1197         /* block and listen to all signals on signalfd */
1198         sigfillset(&mask);
1199         sigprocmask(SIG_SETMASK, &mask, &sigmask_orig);
1200         fd_signal = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
1201         if (fd_signal < 0) {
1202                 fprintf(stderr, "error creating signalfd\n");
1203                 log_error("error creating signalfd");
1204                 rc = 5;
1205                 goto exit;
1206         }
1207
1208         /* unnamed socket from workers to the main daemon */
1209         if (socketpair(AF_LOCAL, SOCK_DGRAM|SOCK_CLOEXEC, 0, worker_watch) < 0) {
1210                 fprintf(stderr, "error creating socketpair\n");
1211                 log_error("error creating socketpair");
1212                 rc = 6;
1213                 goto exit;
1214         }
1215         fd_worker = worker_watch[READ_END];
1216
1217         udev_builtin_init(udev);
1218
1219         rules = udev_rules_new(udev, resolve_names);
1220         if (rules == NULL) {
1221                 log_error("error reading rules");
1222                 goto exit;
1223         }
1224
1225         memzero(&ep_ctrl, sizeof(struct epoll_event));
1226         ep_ctrl.events = EPOLLIN;
1227         ep_ctrl.data.fd = fd_ctrl;
1228
1229         memzero(&ep_inotify, sizeof(struct epoll_event));
1230         ep_inotify.events = EPOLLIN;
1231         ep_inotify.data.fd = fd_inotify;
1232
1233         memzero(&ep_signal, sizeof(struct epoll_event));
1234         ep_signal.events = EPOLLIN;
1235         ep_signal.data.fd = fd_signal;
1236
1237         memzero(&ep_netlink, sizeof(struct epoll_event));
1238         ep_netlink.events = EPOLLIN;
1239         ep_netlink.data.fd = fd_netlink;
1240
1241         memzero(&ep_worker, sizeof(struct epoll_event));
1242         ep_worker.events = EPOLLIN;
1243         ep_worker.data.fd = fd_worker;
1244
1245         fd_ep = epoll_create1(EPOLL_CLOEXEC);
1246         if (fd_ep < 0) {
1247                 log_error("error creating epoll fd: %m");
1248                 goto exit;
1249         }
1250         if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_ctrl, &ep_ctrl) < 0 ||
1251             epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_inotify, &ep_inotify) < 0 ||
1252             epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_signal, &ep_signal) < 0 ||
1253             epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_netlink, &ep_netlink) < 0 ||
1254             epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_worker, &ep_worker) < 0) {
1255                 log_error("fail to add fds to epoll: %m");
1256                 goto exit;
1257         }
1258
1259         if (children_max <= 0) {
1260                 cpu_set_t cpu_set;
1261
1262                 children_max = 8;
1263
1264                 if (sched_getaffinity(0, sizeof (cpu_set), &cpu_set) == 0) {
1265                         children_max +=  CPU_COUNT(&cpu_set) * 2;
1266                 }
1267         }
1268         log_debug("set children_max to %u", children_max);
1269
1270         rc = udev_rules_apply_static_dev_perms(rules);
1271         if (rc < 0)
1272                 log_error("failed to apply permissions on static device nodes - %s", strerror(-rc));
1273
1274         udev_list_node_init(&event_list);
1275         udev_list_node_init(&worker_list);
1276
1277         for (;;) {
1278                 static usec_t last_usec;
1279                 struct epoll_event ev[8];
1280                 int fdcount;
1281                 int timeout;
1282                 bool is_worker, is_signal, is_inotify, is_netlink, is_ctrl;
1283                 int i;
1284
1285                 if (udev_exit) {
1286                         /* close sources of new events and discard buffered events */
1287                         if (fd_ctrl >= 0) {
1288                                 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_ctrl, NULL);
1289                                 fd_ctrl = -1;
1290                         }
1291                         if (monitor != NULL) {
1292                                 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_netlink, NULL);
1293                                 udev_monitor_unref(monitor);
1294                                 monitor = NULL;
1295                         }
1296                         if (fd_inotify >= 0) {
1297                                 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_inotify, NULL);
1298                                 close(fd_inotify);
1299                                 fd_inotify = -1;
1300                         }
1301
1302                         /* discard queued events and kill workers */
1303                         event_queue_cleanup(udev, EVENT_QUEUED);
1304                         worker_kill(udev);
1305
1306                         /* exit after all has cleaned up */
1307                         if (udev_list_node_is_empty(&event_list) && children == 0)
1308                                 break;
1309
1310                         /* timeout at exit for workers to finish */
1311                         timeout = 30 * MSEC_PER_SEC;
1312                 } else if (udev_list_node_is_empty(&event_list) && children == 0) {
1313                         /* we are idle */
1314                         timeout = -1;
1315
1316                         /* cleanup possible left-over processes in our cgroup */
1317                         if (udev_cgroup)
1318                                 cg_kill(SYSTEMD_CGROUP_CONTROLLER, udev_cgroup, SIGKILL, false, true, NULL);
1319                 } else {
1320                         /* kill idle or hanging workers */
1321                         timeout = 3 * MSEC_PER_SEC;
1322                 }
1323
1324                 /* tell settle that we are busy or idle */
1325                 if (!udev_list_node_is_empty(&event_list)) {
1326                         int fd;
1327
1328                         fd = open("/run/udev/queue", O_WRONLY|O_CREAT|O_CLOEXEC|O_TRUNC|O_NOFOLLOW, 0444);
1329                         if (fd >= 0)
1330                                 close(fd);
1331                 } else {
1332                         unlink("/run/udev/queue");
1333                 }
1334
1335                 fdcount = epoll_wait(fd_ep, ev, ELEMENTSOF(ev), timeout);
1336                 if (fdcount < 0)
1337                         continue;
1338
1339                 if (fdcount == 0) {
1340                         struct udev_list_node *loop;
1341
1342                         /* timeout */
1343                         if (udev_exit) {
1344                                 log_error("timeout, giving up waiting for workers to finish");
1345                                 break;
1346                         }
1347
1348                         /* kill idle workers */
1349                         if (udev_list_node_is_empty(&event_list)) {
1350                                 log_debug("cleanup idle workers");
1351                                 worker_kill(udev);
1352                         }
1353
1354                         /* check for hanging events */
1355                         udev_list_node_foreach(loop, &worker_list) {
1356                                 struct worker *worker = node_to_worker(loop);
1357
1358                                 if (worker->state != WORKER_RUNNING)
1359                                         continue;
1360
1361                                 if ((now(CLOCK_MONOTONIC) - worker->event_start_usec) > 30 * USEC_PER_SEC) {
1362                                         log_error("worker [%u] %s timeout; kill it", worker->pid,
1363                                             worker->event ? worker->event->devpath : "<idle>");
1364                                         kill(worker->pid, SIGKILL);
1365                                         worker->state = WORKER_KILLED;
1366
1367                                         /* drop reference taken for state 'running' */
1368                                         worker_unref(worker);
1369                                         if (worker->event) {
1370                                                 log_error("seq %llu '%s' killed", udev_device_get_seqnum(worker->event->dev), worker->event->devpath);
1371                                                 worker->event->exitcode = -64;
1372                                                 event_queue_delete(worker->event);
1373                                                 worker->event = NULL;
1374                                         }
1375                                 }
1376                         }
1377
1378                 }
1379
1380                 is_worker = is_signal = is_inotify = is_netlink = is_ctrl = false;
1381                 for (i = 0; i < fdcount; i++) {
1382                         if (ev[i].data.fd == fd_worker && ev[i].events & EPOLLIN)
1383                                 is_worker = true;
1384                         else if (ev[i].data.fd == fd_netlink && ev[i].events & EPOLLIN)
1385                                 is_netlink = true;
1386                         else if (ev[i].data.fd == fd_signal && ev[i].events & EPOLLIN)
1387                                 is_signal = true;
1388                         else if (ev[i].data.fd == fd_inotify && ev[i].events & EPOLLIN)
1389                                 is_inotify = true;
1390                         else if (ev[i].data.fd == fd_ctrl && ev[i].events & EPOLLIN)
1391                                 is_ctrl = true;
1392                 }
1393
1394                 /* check for changed config, every 3 seconds at most */
1395                 if ((now(CLOCK_MONOTONIC) - last_usec) > 3 * USEC_PER_SEC) {
1396                         if (udev_rules_check_timestamp(rules))
1397                                 reload = true;
1398                         if (udev_builtin_validate(udev))
1399                                 reload = true;
1400
1401                         last_usec = now(CLOCK_MONOTONIC);
1402                 }
1403
1404                 /* reload requested, HUP signal received, rules changed, builtin changed */
1405                 if (reload) {
1406                         worker_kill(udev);
1407                         rules = udev_rules_unref(rules);
1408                         udev_builtin_exit(udev);
1409                         reload = false;
1410                 }
1411
1412                 /* event has finished */
1413                 if (is_worker)
1414                         worker_returned(fd_worker);
1415
1416                 if (is_netlink) {
1417                         struct udev_device *dev;
1418
1419                         dev = udev_monitor_receive_device(monitor);
1420                         if (dev != NULL) {
1421                                 udev_device_set_usec_initialized(dev, now(CLOCK_MONOTONIC));
1422                                 if (event_queue_insert(dev) < 0)
1423                                         udev_device_unref(dev);
1424                         }
1425                 }
1426
1427                 /* start new events */
1428                 if (!udev_list_node_is_empty(&event_list) && !udev_exit && !stop_exec_queue) {
1429                         udev_builtin_init(udev);
1430                         if (rules == NULL)
1431                                 rules = udev_rules_new(udev, resolve_names);
1432                         if (rules != NULL)
1433                                 event_queue_start(udev);
1434                 }
1435
1436                 if (is_signal) {
1437                         struct signalfd_siginfo fdsi;
1438                         ssize_t size;
1439
1440                         size = read(fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
1441                         if (size == sizeof(struct signalfd_siginfo))
1442                                 handle_signal(udev, fdsi.ssi_signo);
1443                 }
1444
1445                 /* we are shutting down, the events below are not handled anymore */
1446                 if (udev_exit)
1447                         continue;
1448
1449                 /* device node watch */
1450                 if (is_inotify)
1451                         handle_inotify(udev);
1452
1453                 /*
1454                  * This needs to be after the inotify handling, to make sure,
1455                  * that the ping is send back after the possibly generated
1456                  * "change" events by the inotify device node watch.
1457                  *
1458                  * A single time we may receive a client connection which we need to
1459                  * keep open to block the client. It will be closed right before we
1460                  * exit.
1461                  */
1462                 if (is_ctrl)
1463                         ctrl_conn = handle_ctrl_msg(udev_ctrl);
1464         }
1465
1466         rc = EXIT_SUCCESS;
1467 exit:
1468         udev_ctrl_cleanup(udev_ctrl);
1469         unlink("/run/udev/queue");
1470 exit_daemonize:
1471         if (fd_ep >= 0)
1472                 close(fd_ep);
1473         worker_list_cleanup(udev);
1474         event_queue_cleanup(udev, EVENT_UNDEF);
1475         udev_rules_unref(rules);
1476         udev_builtin_exit(udev);
1477         if (fd_signal >= 0)
1478                 close(fd_signal);
1479         if (worker_watch[READ_END] >= 0)
1480                 close(worker_watch[READ_END]);
1481         if (worker_watch[WRITE_END] >= 0)
1482                 close(worker_watch[WRITE_END]);
1483         udev_monitor_unref(monitor);
1484         udev_ctrl_connection_unref(ctrl_conn);
1485         udev_ctrl_unref(udev_ctrl);
1486         label_finish();
1487         udev_unref(udev);
1488         log_close();
1489         return rc;
1490 }