src/udev/udevd.c

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