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 /* read inotify messages */
 737 static int handle_inotify(struct udev *udev)
 738 {
 739         int nbytes, pos;
 740         char *buf;
 741         struct inotify_event *ev;
 742
 743         if ((ioctl(fd_inotify, FIONREAD, &nbytes) < 0) || (nbytes <= 0))
 744                 return 0;
 745
 746         buf = malloc(nbytes);
 747         if (buf == NULL) {
 748                 log_error("error getting buffer for inotify");
 749                 return -1;
 750         }
 751
 752         nbytes = read(fd_inotify, buf, nbytes);
 753
 754         for (pos = 0; pos < nbytes; pos += sizeof(struct inotify_event) + ev->len) {
 755                 struct udev_device *dev;
 756
 757                 ev = (struct inotify_event *)(buf + pos);
 758                 dev = udev_watch_lookup(udev, ev->wd);
 759                 if (dev != NULL) {
 760                         log_debug("inotify event: %x for %s", ev->mask, udev_device_get_devnode(dev));
 761                         if (ev->mask & IN_CLOSE_WRITE) {
 762                                 char filename[UTIL_PATH_SIZE];
 763                                 int fd;
 764
 765                                 log_debug("device %s closed, synthesising 'change'", udev_device_get_devnode(dev));
 766                                 strscpyl(filename, sizeof(filename), udev_device_get_syspath(dev), "/uevent", NULL);
 767                                 fd = open(filename, O_WRONLY|O_CLOEXEC);
 768                                 if (fd >= 0) {
 769                                         if (write(fd, "change", 6) < 0)
 770                                                 log_debug("error writing uevent: %m");
 771                                         close(fd);
 772                                 }
 773                         }
 774                         if (ev->mask & IN_IGNORED)
 775                                 udev_watch_end(udev, dev);
 776
 777                         udev_device_unref(dev);
 778                 }
 779
 780         }
 781
 782         free(buf);
 783         return 0;
 784 }
 785
 786 static void handle_signal(struct udev *udev, int signo)
 787 {
 788         switch (signo) {
 789         case SIGINT:
 790         case SIGTERM:
 791                 udev_exit = true;
 792                 break;
 793         case SIGCHLD:
 794                 for (;;) {
 795                         pid_t pid;
 796                         int status;
 797                         struct udev_list_node *loop, *tmp;
 798
 799                         pid = waitpid(-1, &status, WNOHANG);
 800                         if (pid <= 0)
 801                                 break;
 802
 803                         udev_list_node_foreach_safe(loop, tmp, &worker_list) {
 804                                 struct worker *worker = node_to_worker(loop);
 805
 806                                 if (worker->pid != pid)
 807                                         continue;
 808                                 log_debug("worker [%u] exit", pid);
 809
 810                                 if (WIFEXITED(status)) {
 811                                         if (WEXITSTATUS(status) != 0)
 812                                                 log_error("worker [%u] exit with return code %i",
 813                                                           pid, WEXITSTATUS(status));
 814                                 } else if (WIFSIGNALED(status)) {
 815                                         log_error("worker [%u] terminated by signal %i (%s)",
 816                                                   pid, WTERMSIG(status), strsignal(WTERMSIG(status)));
 817                                 } else if (WIFSTOPPED(status)) {
 818                                         log_error("worker [%u] stopped", pid);
 819                                 } else if (WIFCONTINUED(status)) {
 820                                         log_error("worker [%u] continued", pid);
 821                                 } else {
 822                                         log_error("worker [%u] exit with status 0x%04x", pid, status);
 823                                 }
 824
 825                                 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
 826                                         if (worker->event) {
 827                                                 log_error("worker [%u] failed while handling '%s'",
 828                                                           pid, worker->event->devpath);
 829                                                 worker->event->exitcode = -32;
 830                                                 event_queue_delete(worker->event);
 831
 832                                                 /* drop reference taken for state 'running' */
 833                                                 worker_unref(worker);
 834                                         }
 835                                 }
 836                                 worker_unref(worker);
 837                                 break;
 838                         }
 839                 }
 840                 break;
 841         case SIGHUP:
 842                 reload = true;
 843                 break;
 844         }
 845 }
 846
 847 static int systemd_fds(struct udev *udev, int *rctrl, int *rnetlink)
 848 {
 849         int ctrl = -1, netlink = -1;
 850         int fd, n;
 851
 852         n = sd_listen_fds(true);
 853         if (n <= 0)
 854                 return -1;
 855
 856         for (fd = SD_LISTEN_FDS_START; fd < n + SD_LISTEN_FDS_START; fd++) {
 857                 if (sd_is_socket(fd, AF_LOCAL, SOCK_SEQPACKET, -1)) {
 858                         if (ctrl >= 0)
 859                                 return -1;
 860                         ctrl = fd;
 861                         continue;
 862                 }
 863
 864                 if (sd_is_socket(fd, AF_NETLINK, SOCK_RAW, -1)) {
 865                         if (netlink >= 0)
 866                                 return -1;
 867                         netlink = fd;
 868                         continue;
 869                 }
 870
 871                 return -1;
 872         }
 873
 874         if (ctrl < 0 || netlink < 0)
 875                 return -1;
 876
 877         log_debug("ctrl=%i netlink=%i", ctrl, netlink);
 878         *rctrl = ctrl;
 879         *rnetlink = netlink;
 880         return 0;
 881 }
 882
 883 /*
 884  * read the kernel commandline, in case we need to get into debug mode
 885  *   udev.log-priority=<level>              syslog priority
 886  *   udev.children-max=<number of workers>  events are fully serialized if set to 1
 887  *   udev.exec-delay=<number of seconds>    delay execution of every executed program
 888  */
 889 static void kernel_cmdline_options(struct udev *udev)
 890 {
 891         _cleanup_free_ char *line = NULL;
 892         char *w, *state;
 893         size_t l;
 894         int r;
 895
 896         r = proc_cmdline(&line);
 897         if (r < 0)
 898                 log_warning("Failed to read /proc/cmdline, ignoring: %s", strerror(-r));
 899         if (r <= 0)
 900                 return;
 901
 902         FOREACH_WORD_QUOTED(w, l, line, state) {
 903                 char *s, *opt;
 904
 905                 s = strndup(w, l);
 906                 if (!s)
 907                         break;
 908
 909                 /* accept the same options for the initrd, prefixed with "rd." */
 910                 if (in_initrd() && startswith(s, "rd."))
 911                         opt = s + 3;
 912                 else
 913                         opt = s;
 914
 915                 if (startswith(opt, "udev.log-priority=")) {
 916                         int prio;
 917
 918                         prio = util_log_priority(opt + 18);
 919                         log_set_max_level(prio);
 920                         udev_set_log_priority(udev, prio);
 921                 } else if (startswith(opt, "udev.children-max=")) {
 922                         children_max = strtoul(opt + 18, NULL, 0);
 923                 } else if (startswith(opt, "udev.exec-delay=")) {
 924                         exec_delay = strtoul(opt + 16, NULL, 0);
 925                 }
 926
 927                 free(s);
 928         }
 929 }
 930
 931 int main(int argc, char *argv[])
 932 {
 933         struct udev *udev;
 934         sigset_t mask;
 935         int daemonize = false;
 936         int resolve_names = 1;
 937         static const struct option options[] = {
 938                 { "daemon", no_argument, NULL, 'd' },
 939                 { "debug", no_argument, NULL, 'D' },
 940                 { "children-max", required_argument, NULL, 'c' },
 941                 { "exec-delay", required_argument, NULL, 'e' },
 942                 { "resolve-names", required_argument, NULL, 'N' },
 943                 { "help", no_argument, NULL, 'h' },
 944                 { "version", no_argument, NULL, 'V' },
 945                 {}
 946         };
 947         int fd_ctrl = -1;
 948         int fd_netlink = -1;
 949         int fd_worker = -1;
 950         struct epoll_event ep_ctrl, ep_inotify, ep_signal, ep_netlink, ep_worker;
 951         struct udev_ctrl_connection *ctrl_conn = NULL;
 952         int rc = 1;
 953
 954         udev = udev_new();
 955         if (udev == NULL)
 956                 goto exit;
 957
 958         log_set_target(LOG_TARGET_AUTO);
 959         log_parse_environment();
 960         log_open();
 961
 962         udev_set_log_fn(udev, udev_main_log);
 963         log_set_max_level(udev_get_log_priority(udev));
 964
 965         log_debug("version %s", VERSION);
 966         label_init("/dev");
 967
 968         for (;;) {
 969                 int option;
 970
 971                 option = getopt_long(argc, argv, "c:de:DtN:hV", options, NULL);
 972                 if (option == -1)
 973                         break;
 974
 975                 switch (option) {
 976                 case 'd':
 977                         daemonize = true;
 978                         break;
 979                 case 'c':
 980                         children_max = strtoul(optarg, NULL, 0);
 981                         break;
 982                 case 'e':
 983                         exec_delay = strtoul(optarg, NULL, 0);
 984                         break;
 985                 case 'D':
 986                         debug = true;
 987                         log_set_max_level(LOG_DEBUG);
 988                         udev_set_log_priority(udev, LOG_DEBUG);
 989                         break;
 990                 case 'N':
 991                         if (streq(optarg, "early")) {
 992                                 resolve_names = 1;
 993                         } else if (streq(optarg, "late")) {
 994                                 resolve_names = 0;
 995                         } else if (streq(optarg, "never")) {
 996                                 resolve_names = -1;
 997                         } else {
 998                                 fprintf(stderr, "resolve-names must be early, late or never\n");
 999                                 log_error("resolve-names must be early, late or never");
1000                                 goto exit;
1001                         }
1002                         break;
1003                 case 'h':
1004                         printf("Usage: udevd OPTIONS\n"
1005                                "  --daemon\n"
1006                                "  --debug\n"
1007                                "  --children-max=<maximum number of workers>\n"
1008                                "  --exec-delay=<seconds to wait before executing RUN=>\n"
1009                                "  --resolve-names=early|late|never\n"
1010                                "  --version\n"
1011                                "  --help\n"
1012                                "\n");
1013                         goto exit;
1014                 case 'V':
1015                         printf("%s\n", VERSION);
1016                         goto exit;
1017                 default:
1018                         goto exit;
1019                 }
1020         }
1021
1022         kernel_cmdline_options(udev);
1023
1024         if (getuid() != 0) {
1025                 fprintf(stderr, "root privileges required\n");
1026                 log_error("root privileges required");
1027                 goto exit;
1028         }
1029
1030         /* set umask before creating any file/directory */
1031         chdir("/");
1032         umask(022);
1033
1034         mkdir("/run/udev", 0755);
1035
1036         dev_setup(NULL);
1037
1038         /* before opening new files, make sure std{in,out,err} fds are in a sane state */
1039         if (daemonize) {
1040                 int fd;
1041
1042                 fd = open("/dev/null", O_RDWR);
1043                 if (fd >= 0) {
1044                         if (write(STDOUT_FILENO, 0, 0) < 0)
1045                                 dup2(fd, STDOUT_FILENO);
1046                         if (write(STDERR_FILENO, 0, 0) < 0)
1047                                 dup2(fd, STDERR_FILENO);
1048                         if (fd > STDERR_FILENO)
1049                                 close(fd);
1050                 } else {
1051                         fprintf(stderr, "cannot open /dev/null\n");
1052                         log_error("cannot open /dev/null");
1053                 }
1054         }
1055
1056         if (systemd_fds(udev, &fd_ctrl, &fd_netlink) >= 0) {
1057                 /* get control and netlink socket from systemd */
1058                 udev_ctrl = udev_ctrl_new_from_fd(udev, fd_ctrl);
1059                 if (udev_ctrl == NULL) {
1060                         log_error("error taking over udev control socket");
1061                         rc = 1;
1062                         goto exit;
1063                 }
1064
1065                 monitor = udev_monitor_new_from_netlink_fd(udev, "kernel", fd_netlink);
1066                 if (monitor == NULL) {
1067                         log_error("error taking over netlink socket");
1068                         rc = 3;
1069                         goto exit;
1070                 }
1071
1072                 /* get our own cgroup, we regularly kill everything udev has left behind */
1073                 if (cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, 0, &udev_cgroup) < 0)
1074                         udev_cgroup = NULL;
1075         } else {
1076                 /* open control and netlink socket */
1077                 udev_ctrl = udev_ctrl_new(udev);
1078                 if (udev_ctrl == NULL) {
1079                         fprintf(stderr, "error initializing udev control socket");
1080                         log_error("error initializing udev control socket");
1081                         rc = 1;
1082                         goto exit;
1083                 }
1084                 fd_ctrl = udev_ctrl_get_fd(udev_ctrl);
1085
1086                 monitor = udev_monitor_new_from_netlink(udev, "kernel");
1087                 if (monitor == NULL) {
1088                         fprintf(stderr, "error initializing netlink socket\n");
1089                         log_error("error initializing netlink socket");
1090                         rc = 3;
1091                         goto exit;
1092                 }
1093                 fd_netlink = udev_monitor_get_fd(monitor);
1094         }
1095
1096         if (udev_monitor_enable_receiving(monitor) < 0) {
1097                 fprintf(stderr, "error binding netlink socket\n");
1098                 log_error("error binding netlink socket");
1099                 rc = 3;
1100                 goto exit;
1101         }
1102
1103         if (udev_ctrl_enable_receiving(udev_ctrl) < 0) {
1104                 fprintf(stderr, "error binding udev control socket\n");
1105                 log_error("error binding udev control socket");
1106                 rc = 1;
1107                 goto exit;
1108         }
1109
1110         udev_monitor_set_receive_buffer_size(monitor, 128 * 1024 * 1024);
1111
1112         if (daemonize) {
1113                 pid_t pid;
1114
1115                 pid = fork();
1116                 switch (pid) {
1117                 case 0:
1118                         break;
1119                 case -1:
1120                         log_error("fork of daemon failed: %m");
1121                         rc = 4;
1122                         goto exit;
1123                 default:
1124                         rc = EXIT_SUCCESS;
1125                         goto exit_daemonize;
1126                 }
1127
1128                 setsid();
1129
1130                 write_string_file("/proc/self/oom_score_adj", "-1000");
1131         } else {
1132                 sd_notify(1, "READY=1");
1133         }
1134
1135         print_kmsg("starting version " VERSION "\n");
1136
1137         if (!debug) {
1138                 int fd;
1139
1140                 fd = open("/dev/null", O_RDWR);
1141                 if (fd >= 0) {
1142                         dup2(fd, STDIN_FILENO);
1143                         dup2(fd, STDOUT_FILENO);
1144                         dup2(fd, STDERR_FILENO);
1145                         close(fd);
1146                 }
1147         }
1148
1149         fd_inotify = udev_watch_init(udev);
1150         if (fd_inotify < 0) {
1151                 fprintf(stderr, "error initializing inotify\n");
1152                 log_error("error initializing inotify");
1153                 rc = 4;
1154                 goto exit;
1155         }
1156         udev_watch_restore(udev);
1157
1158         /* block and listen to all signals on signalfd */
1159         sigfillset(&mask);
1160         sigprocmask(SIG_SETMASK, &mask, &sigmask_orig);
1161         fd_signal = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
1162         if (fd_signal < 0) {
1163                 fprintf(stderr, "error creating signalfd\n");
1164                 log_error("error creating signalfd");
1165                 rc = 5;
1166                 goto exit;
1167         }
1168
1169         /* unnamed socket from workers to the main daemon */
1170         if (socketpair(AF_LOCAL, SOCK_DGRAM|SOCK_CLOEXEC, 0, worker_watch) < 0) {
1171                 fprintf(stderr, "error creating socketpair\n");
1172                 log_error("error creating socketpair");
1173                 rc = 6;
1174                 goto exit;
1175         }
1176         fd_worker = worker_watch[READ_END];
1177
1178         udev_builtin_init(udev);
1179
1180         rules = udev_rules_new(udev, resolve_names);
1181         if (rules == NULL) {
1182                 log_error("error reading rules");
1183                 goto exit;
1184         }
1185
1186         memzero(&ep_ctrl, sizeof(struct epoll_event));
1187         ep_ctrl.events = EPOLLIN;
1188         ep_ctrl.data.fd = fd_ctrl;
1189
1190         memzero(&ep_inotify, sizeof(struct epoll_event));
1191         ep_inotify.events = EPOLLIN;
1192         ep_inotify.data.fd = fd_inotify;
1193
1194         memzero(&ep_signal, sizeof(struct epoll_event));
1195         ep_signal.events = EPOLLIN;
1196         ep_signal.data.fd = fd_signal;
1197
1198         memzero(&ep_netlink, sizeof(struct epoll_event));
1199         ep_netlink.events = EPOLLIN;
1200         ep_netlink.data.fd = fd_netlink;
1201
1202         memzero(&ep_worker, sizeof(struct epoll_event));
1203         ep_worker.events = EPOLLIN;
1204         ep_worker.data.fd = fd_worker;
1205
1206         fd_ep = epoll_create1(EPOLL_CLOEXEC);
1207         if (fd_ep < 0) {
1208                 log_error("error creating epoll fd: %m");
1209                 goto exit;
1210         }
1211         if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_ctrl, &ep_ctrl) < 0 ||
1212             epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_inotify, &ep_inotify) < 0 ||
1213             epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_signal, &ep_signal) < 0 ||
1214             epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_netlink, &ep_netlink) < 0 ||
1215             epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_worker, &ep_worker) < 0) {
1216                 log_error("fail to add fds to epoll: %m");
1217                 goto exit;
1218         }
1219
1220         if (children_max <= 0) {
1221                 cpu_set_t cpu_set;
1222
1223                 children_max = 8;
1224
1225                 if (sched_getaffinity(0, sizeof (cpu_set), &cpu_set) == 0) {
1226                         children_max +=  CPU_COUNT(&cpu_set) * 2;
1227                 }
1228         }
1229         log_debug("set children_max to %u", children_max);
1230
1231         rc = udev_rules_apply_static_dev_perms(rules);
1232         if (rc < 0)
1233                 log_error("failed to apply permissions on static device nodes - %s", strerror(-rc));
1234
1235         udev_list_node_init(&event_list);
1236         udev_list_node_init(&worker_list);
1237
1238         for (;;) {
1239                 static usec_t last_usec;
1240                 struct epoll_event ev[8];
1241                 int fdcount;
1242                 int timeout;
1243                 bool is_worker, is_signal, is_inotify, is_netlink, is_ctrl;
1244                 int i;
1245
1246                 if (udev_exit) {
1247                         /* close sources of new events and discard buffered events */
1248                         if (fd_ctrl >= 0) {
1249                                 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_ctrl, NULL);
1250                                 fd_ctrl = -1;
1251                         }
1252                         if (monitor != NULL) {
1253                                 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_netlink, NULL);
1254                                 udev_monitor_unref(monitor);
1255                                 monitor = NULL;
1256                         }
1257                         if (fd_inotify >= 0) {
1258                                 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_inotify, NULL);
1259                                 close(fd_inotify);
1260                                 fd_inotify = -1;
1261                         }
1262
1263                         /* discard queued events and kill workers */
1264                         event_queue_cleanup(udev, EVENT_QUEUED);
1265                         worker_kill(udev);
1266
1267                         /* exit after all has cleaned up */
1268                         if (udev_list_node_is_empty(&event_list) && children == 0)
1269                                 break;
1270
1271                         /* timeout at exit for workers to finish */
1272                         timeout = 30 * MSEC_PER_SEC;
1273                 } else if (udev_list_node_is_empty(&event_list) && children == 0) {
1274                         /* we are idle */
1275                         timeout = -1;
1276
1277                         /* cleanup possible left-over processes in our cgroup */
1278                         if (udev_cgroup)
1279                                 cg_kill(SYSTEMD_CGROUP_CONTROLLER, udev_cgroup, SIGKILL, false, true, NULL);
1280                 } else {
1281                         /* kill idle or hanging workers */
1282                         timeout = 3 * MSEC_PER_SEC;
1283                 }
1284
1285                 /* tell settle that we are busy or idle */
1286                 if (!udev_list_node_is_empty(&event_list)) {
1287                         int fd;
1288
1289                         fd = open("/run/udev/queue", O_WRONLY|O_CREAT|O_CLOEXEC|O_TRUNC|O_NOFOLLOW, 0444);
1290                         if (fd >= 0)
1291                                 close(fd);
1292                 } else {
1293                         unlink("/run/udev/queue");
1294                 }
1295
1296                 fdcount = epoll_wait(fd_ep, ev, ELEMENTSOF(ev), timeout);
1297                 if (fdcount < 0)
1298                         continue;
1299
1300                 if (fdcount == 0) {
1301                         struct udev_list_node *loop;
1302
1303                         /* timeout */
1304                         if (udev_exit) {
1305                                 log_error("timeout, giving up waiting for workers to finish");
1306                                 break;
1307                         }
1308
1309                         /* kill idle workers */
1310                         if (udev_list_node_is_empty(&event_list)) {
1311                                 log_debug("cleanup idle workers");
1312                                 worker_kill(udev);
1313                         }
1314
1315                         /* check for hanging events */
1316                         udev_list_node_foreach(loop, &worker_list) {
1317                                 struct worker *worker = node_to_worker(loop);
1318
1319                                 if (worker->state != WORKER_RUNNING)
1320                                         continue;
1321
1322                                 if ((now(CLOCK_MONOTONIC) - worker->event_start_usec) > 30 * USEC_PER_SEC) {
1323                                         log_error("worker [%u] %s timeout; kill it", worker->pid,
1324                                             worker->event ? worker->event->devpath : "<idle>");
1325                                         kill(worker->pid, SIGKILL);
1326                                         worker->state = WORKER_KILLED;
1327
1328                                         /* drop reference taken for state 'running' */
1329                                         worker_unref(worker);
1330                                         if (worker->event) {
1331                                                 log_error("seq %llu '%s' killed", udev_device_get_seqnum(worker->event->dev), worker->event->devpath);
1332                                                 worker->event->exitcode = -64;
1333                                                 event_queue_delete(worker->event);
1334                                                 worker->event = NULL;
1335                                         }
1336                                 }
1337                         }
1338
1339                 }
1340
1341                 is_worker = is_signal = is_inotify = is_netlink = is_ctrl = false;
1342                 for (i = 0; i < fdcount; i++) {
1343                         if (ev[i].data.fd == fd_worker && ev[i].events & EPOLLIN)
1344                                 is_worker = true;
1345                         else if (ev[i].data.fd == fd_netlink && ev[i].events & EPOLLIN)
1346                                 is_netlink = true;
1347                         else if (ev[i].data.fd == fd_signal && ev[i].events & EPOLLIN)
1348                                 is_signal = true;
1349                         else if (ev[i].data.fd == fd_inotify && ev[i].events & EPOLLIN)
1350                                 is_inotify = true;
1351                         else if (ev[i].data.fd == fd_ctrl && ev[i].events & EPOLLIN)
1352                                 is_ctrl = true;
1353                 }
1354
1355                 /* check for changed config, every 3 seconds at most */
1356                 if ((now(CLOCK_MONOTONIC) - last_usec) > 3 * USEC_PER_SEC) {
1357                         if (udev_rules_check_timestamp(rules))
1358                                 reload = true;
1359                         if (udev_builtin_validate(udev))
1360                                 reload = true;
1361
1362                         last_usec = now(CLOCK_MONOTONIC);
1363                 }
1364
1365                 /* reload requested, HUP signal received, rules changed, builtin changed */
1366                 if (reload) {
1367                         worker_kill(udev);
1368                         rules = udev_rules_unref(rules);
1369                         udev_builtin_exit(udev);
1370                         reload = false;
1371                 }
1372
1373                 /* event has finished */
1374                 if (is_worker)
1375                         worker_returned(fd_worker);
1376
1377                 if (is_netlink) {
1378                         struct udev_device *dev;
1379
1380                         dev = udev_monitor_receive_device(monitor);
1381                         if (dev != NULL) {
1382                                 udev_device_set_usec_initialized(dev, now(CLOCK_MONOTONIC));
1383                                 if (event_queue_insert(dev) < 0)
1384                                         udev_device_unref(dev);
1385                         }
1386                 }
1387
1388                 /* start new events */
1389                 if (!udev_list_node_is_empty(&event_list) && !udev_exit && !stop_exec_queue) {
1390                         udev_builtin_init(udev);
1391                         if (rules == NULL)
1392                                 rules = udev_rules_new(udev, resolve_names);
1393                         if (rules != NULL)
1394                                 event_queue_start(udev);
1395                 }
1396
1397                 if (is_signal) {
1398                         struct signalfd_siginfo fdsi;
1399                         ssize_t size;
1400
1401                         size = read(fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
1402                         if (size == sizeof(struct signalfd_siginfo))
1403                                 handle_signal(udev, fdsi.ssi_signo);
1404                 }
1405
1406                 /* we are shutting down, the events below are not handled anymore */
1407                 if (udev_exit)
1408                         continue;
1409
1410                 /* device node watch */
1411                 if (is_inotify)
1412                         handle_inotify(udev);
1413
1414                 /*
1415                  * This needs to be after the inotify handling, to make sure,
1416                  * that the ping is send back after the possibly generated
1417                  * "change" events by the inotify device node watch.
1418                  *
1419                  * A single time we may receive a client connection which we need to
1420                  * keep open to block the client. It will be closed right before we
1421                  * exit.
1422                  */
1423                 if (is_ctrl)
1424                         ctrl_conn = handle_ctrl_msg(udev_ctrl);
1425         }
1426
1427         rc = EXIT_SUCCESS;
1428 exit:
1429         udev_ctrl_cleanup(udev_ctrl);
1430         unlink("/run/udev/queue");
1431 exit_daemonize:
1432         if (fd_ep >= 0)
1433                 close(fd_ep);
1434         worker_list_cleanup(udev);
1435         event_queue_cleanup(udev, EVENT_UNDEF);
1436         udev_rules_unref(rules);
1437         udev_builtin_exit(udev);
1438         if (fd_signal >= 0)
1439                 close(fd_signal);
1440         if (worker_watch[READ_END] >= 0)
1441                 close(worker_watch[READ_END]);
1442         if (worker_watch[WRITE_END] >= 0)
1443                 close(worker_watch[WRITE_END]);
1444         udev_monitor_unref(monitor);
1445         udev_ctrl_connection_unref(ctrl_conn);
1446         udev_ctrl_unref(udev_ctrl);
1447         label_finish();
1448         udev_unref(udev);
1449         log_close();
1450         return rc;
1451 }