src/udev/udevd.c

   1 /*
   2  * Copyright (C) 2004-2012 Kay Sievers <kay.sievers@vrfy.org>
   3  * Copyright (C) 2004 Chris Friesen <chris_friesen@sympatico.ca>
   4  * Copyright (C) 2009 Canonical Ltd.
   5  * Copyright (C) 2009 Scott James Remnant <scott@netsplit.com>
   6  *
   7  * This program is free software: you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation, either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include <stddef.h>
  22 #include <signal.h>
  23 #include <unistd.h>
  24 #include <errno.h>
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <stdbool.h>
  28 #include <string.h>
  29 #include <ctype.h>
  30 #include <fcntl.h>
  31 #include <time.h>
  32 #include <getopt.h>
  33 #include <dirent.h>
  34 #include <sys/time.h>
  35 #include <sys/prctl.h>
  36 #include <sys/socket.h>
  37 #include <sys/un.h>
  38 #include <sys/signalfd.h>
  39 #include <sys/epoll.h>
  40 #include <sys/poll.h>
  41 #include <sys/wait.h>
  42 #include <sys/stat.h>
  43 #include <sys/ioctl.h>
  44 #include <sys/inotify.h>
  45 #include <sys/utsname.h>
  46
  47 #include "udev.h"
  48 #include "sd-daemon.h"
  49
  50 static bool debug;
  51
  52 void udev_main_log(struct udev *udev, int priority,
  53                    const char *file, int line, const char *fn,
  54                    const char *format, va_list args)
  55 {
  56         log_metav(priority, file, line, fn, format, args);
  57 }
  58
  59 static struct udev_rules *rules;
  60 static struct udev_queue_export *udev_queue_export;
  61 static struct udev_ctrl *udev_ctrl;
  62 static struct udev_monitor *monitor;
  63 static int worker_watch[2] = { -1, -1 };
  64 static int fd_signal = -1;
  65 static int fd_ep = -1;
  66 static int fd_inotify = -1;
  67 static bool stop_exec_queue;
  68 static bool reload;
  69 static int children;
  70 static int children_max;
  71 static int exec_delay;
  72 static sigset_t sigmask_orig;
  73 static UDEV_LIST(event_list);
  74 static UDEV_LIST(worker_list);
  75 static bool udev_exit;
  76
  77 enum event_state {
  78         EVENT_UNDEF,
  79         EVENT_QUEUED,
  80         EVENT_RUNNING,
  81 };
  82
  83 struct event {
  84         struct udev_list_node node;
  85         struct udev *udev;
  86         struct udev_device *dev;
  87         enum event_state state;
  88         int exitcode;
  89         unsigned long long int delaying_seqnum;
  90         unsigned long long int seqnum;
  91         const char *devpath;
  92         size_t devpath_len;
  93         const char *devpath_old;
  94         dev_t devnum;
  95         bool is_block;
  96         int ifindex;
  97 };
  98
  99 static struct event *node_to_event(struct udev_list_node *node)
 100 {
 101         char *event;
 102
 103         event = (char *)node;
 104         event -= offsetof(struct event, node);
 105         return (struct event *)event;
 106 }
 107
 108 static void event_queue_cleanup(struct udev *udev, enum event_state type);
 109
 110 enum worker_state {
 111         WORKER_UNDEF,
 112         WORKER_RUNNING,
 113         WORKER_IDLE,
 114         WORKER_KILLED,
 115 };
 116
 117 struct worker {
 118         struct udev_list_node node;
 119         struct udev *udev;
 120         int refcount;
 121         pid_t pid;
 122         struct udev_monitor *monitor;
 123         enum worker_state state;
 124         struct event *event;
 125         unsigned long long event_start_usec;
 126 };
 127
 128 /* passed from worker to main process */
 129 struct worker_message {
 130         pid_t pid;
 131         int exitcode;
 132 };
 133
 134 static struct worker *node_to_worker(struct udev_list_node *node)
 135 {
 136         char *worker;
 137
 138         worker = (char *)node;
 139         worker -= offsetof(struct worker, node);
 140         return (struct worker *)worker;
 141 }
 142
 143 static void event_queue_delete(struct event *event, bool export)
 144 {
 145         udev_list_node_remove(&event->node);
 146
 147         if (export) {
 148                 udev_queue_export_device_finished(udev_queue_export, event->dev);
 149                 log_debug("seq %llu done with %i\n", udev_device_get_seqnum(event->dev), event->exitcode);
 150         }
 151         udev_device_unref(event->dev);
 152         free(event);
 153 }
 154
 155 static struct worker *worker_ref(struct worker *worker)
 156 {
 157         worker->refcount++;
 158         return worker;
 159 }
 160
 161 static void worker_cleanup(struct worker *worker)
 162 {
 163         udev_list_node_remove(&worker->node);
 164         udev_monitor_unref(worker->monitor);
 165         children--;
 166         free(worker);
 167 }
 168
 169 static void worker_unref(struct worker *worker)
 170 {
 171         worker->refcount--;
 172         if (worker->refcount > 0)
 173                 return;
 174         log_debug("worker [%u] cleaned up\n", worker->pid);
 175         worker_cleanup(worker);
 176 }
 177
 178 static void worker_list_cleanup(struct udev *udev)
 179 {
 180         struct udev_list_node *loop, *tmp;
 181
 182         udev_list_node_foreach_safe(loop, tmp, &worker_list) {
 183                 struct worker *worker = node_to_worker(loop);
 184
 185                 worker_cleanup(worker);
 186         }
 187 }
 188
 189 static void worker_new(struct event *event)
 190 {
 191         struct udev *udev = event->udev;
 192         struct worker *worker;
 193         struct udev_monitor *worker_monitor;
 194         pid_t pid;
 195
 196         /* listen for new events */
 197         worker_monitor = udev_monitor_new_from_netlink(udev, NULL);
 198         if (worker_monitor == NULL)
 199                 return;
 200         /* allow the main daemon netlink address to send devices to the worker */
 201         udev_monitor_allow_unicast_sender(worker_monitor, monitor);
 202         udev_monitor_enable_receiving(worker_monitor);
 203
 204         worker = calloc(1, sizeof(struct worker));
 205         if (worker == NULL) {
 206                 udev_monitor_unref(worker_monitor);
 207                 return;
 208         }
 209         /* worker + event reference */
 210         worker->refcount = 2;
 211         worker->udev = udev;
 212
 213         pid = fork();
 214         switch (pid) {
 215         case 0: {
 216                 struct udev_device *dev = NULL;
 217                 int fd_monitor;
 218                 struct epoll_event ep_signal, ep_monitor;
 219                 sigset_t mask;
 220                 int rc = EXIT_SUCCESS;
 221
 222                 /* take initial device from queue */
 223                 dev = event->dev;
 224                 event->dev = NULL;
 225
 226                 free(worker);
 227                 worker_list_cleanup(udev);
 228                 event_queue_cleanup(udev, EVENT_UNDEF);
 229                 udev_queue_export_unref(udev_queue_export);
 230                 udev_monitor_unref(monitor);
 231                 udev_ctrl_unref(udev_ctrl);
 232                 close(fd_signal);
 233                 close(fd_ep);
 234                 close(worker_watch[READ_END]);
 235
 236                 sigfillset(&mask);
 237                 fd_signal = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
 238                 if (fd_signal < 0) {
 239                         log_error("error creating signalfd %m\n");
 240                         rc = 2;
 241                         goto out;
 242                 }
 243
 244                 fd_ep = epoll_create1(EPOLL_CLOEXEC);
 245                 if (fd_ep < 0) {
 246                         log_error("error creating epoll fd: %m\n");
 247                         rc = 3;
 248                         goto out;
 249                 }
 250
 251                 memset(&ep_signal, 0, sizeof(struct epoll_event));
 252                 ep_signal.events = EPOLLIN;
 253                 ep_signal.data.fd = fd_signal;
 254
 255                 fd_monitor = udev_monitor_get_fd(worker_monitor);
 256                 memset(&ep_monitor, 0, sizeof(struct epoll_event));
 257                 ep_monitor.events = EPOLLIN;
 258                 ep_monitor.data.fd = fd_monitor;
 259
 260                 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_signal, &ep_signal) < 0 ||
 261                     epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_monitor, &ep_monitor) < 0) {
 262                         log_error("fail to add fds to epoll: %m\n");
 263                         rc = 4;
 264                         goto out;
 265                 }
 266
 267                 /* request TERM signal if parent exits */
 268                 prctl(PR_SET_PDEATHSIG, SIGTERM);
 269
 270                 for (;;) {
 271                         struct udev_event *udev_event;
 272                         struct worker_message msg;
 273                         int err;
 274
 275                         log_debug("seq %llu running\n", udev_device_get_seqnum(dev));
 276                         udev_event = udev_event_new(dev);
 277                         if (udev_event == NULL) {
 278                                 rc = 5;
 279                                 goto out;
 280                         }
 281
 282                         /* needed for SIGCHLD/SIGTERM in spawn() */
 283                         udev_event->fd_signal = fd_signal;
 284
 285                         if (exec_delay > 0)
 286                                 udev_event->exec_delay = exec_delay;
 287
 288                         /* apply rules, create node, symlinks */
 289                         err = udev_event_execute_rules(udev_event, rules, &sigmask_orig);
 290
 291                         if (err == 0)
 292                                 udev_event_execute_run(udev_event, &sigmask_orig);
 293
 294                         /* apply/restore inotify watch */
 295                         if (err == 0 && udev_event->inotify_watch) {
 296                                 udev_watch_begin(udev, dev);
 297                                 udev_device_update_db(dev);
 298                         }
 299
 300                         /* send processed event back to libudev listeners */
 301                         udev_monitor_send_device(worker_monitor, NULL, dev);
 302
 303                         /* send udevd the result of the event execution */
 304                         memset(&msg, 0, sizeof(struct worker_message));
 305                         if (err != 0)
 306                                 msg.exitcode = err;
 307                         msg.pid = getpid();
 308                         send(worker_watch[WRITE_END], &msg, sizeof(struct worker_message), 0);
 309
 310                         log_debug("seq %llu processed with %i\n", udev_device_get_seqnum(dev), err);
 311
 312                         udev_device_unref(dev);
 313                         dev = NULL;
 314
 315                         if (udev_event->sigterm) {
 316                                 udev_event_unref(udev_event);
 317                                 goto out;
 318                         }
 319
 320                         udev_event_unref(udev_event);
 321
 322                         /* wait for more device messages from main udevd, or term signal */
 323                         while (dev == NULL) {
 324                                 struct epoll_event ev[4];
 325                                 int fdcount;
 326                                 int i;
 327
 328                                 fdcount = epoll_wait(fd_ep, ev, ARRAY_SIZE(ev), -1);
 329                                 if (fdcount < 0) {
 330                                         if (errno == EINTR)
 331                                                 continue;
 332                                         err = -errno;
 333                                         log_error("failed to poll: %m\n");
 334                                         goto out;
 335                                 }
 336
 337                                 for (i = 0; i < fdcount; i++) {
 338                                         if (ev[i].data.fd == fd_monitor && ev[i].events & EPOLLIN) {
 339                                                 dev = udev_monitor_receive_device(worker_monitor);
 340                                                 break;
 341                                         } else if (ev[i].data.fd == fd_signal && ev[i].events & EPOLLIN) {
 342                                                 struct signalfd_siginfo fdsi;
 343                                                 ssize_t size;
 344
 345                                                 size = read(fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
 346                                                 if (size != sizeof(struct signalfd_siginfo))
 347                                                         continue;
 348                                                 switch (fdsi.ssi_signo) {
 349                                                 case SIGTERM:
 350                                                         goto out;
 351                                                 }
 352                                         }
 353                                 }
 354                         }
 355                 }
 356 out:
 357                 udev_device_unref(dev);
 358                 if (fd_signal >= 0)
 359                         close(fd_signal);
 360                 if (fd_ep >= 0)
 361                         close(fd_ep);
 362                 close(fd_inotify);
 363                 close(worker_watch[WRITE_END]);
 364                 udev_rules_unref(rules);
 365                 udev_builtin_exit(udev);
 366                 udev_monitor_unref(worker_monitor);
 367                 udev_unref(udev);
 368                 log_close();
 369                 exit(rc);
 370         }
 371         case -1:
 372                 udev_monitor_unref(worker_monitor);
 373                 event->state = EVENT_QUEUED;
 374                 free(worker);
 375                 log_error("fork of child failed: %m\n");
 376                 break;
 377         default:
 378                 /* close monitor, but keep address around */
 379                 udev_monitor_disconnect(worker_monitor);
 380                 worker->monitor = worker_monitor;
 381                 worker->pid = pid;
 382                 worker->state = WORKER_RUNNING;
 383                 worker->event_start_usec = now_usec();
 384                 worker->event = event;
 385                 event->state = EVENT_RUNNING;
 386                 udev_list_node_append(&worker->node, &worker_list);
 387                 children++;
 388                 log_debug("seq %llu forked new worker [%u]\n", udev_device_get_seqnum(event->dev), pid);
 389                 break;
 390         }
 391 }
 392
 393 static void event_run(struct event *event)
 394 {
 395         struct udev_list_node *loop;
 396
 397         udev_list_node_foreach(loop, &worker_list) {
 398                 struct worker *worker = node_to_worker(loop);
 399                 ssize_t count;
 400
 401                 if (worker->state != WORKER_IDLE)
 402                         continue;
 403
 404                 count = udev_monitor_send_device(monitor, worker->monitor, event->dev);
 405                 if (count < 0) {
 406                         log_error("worker [%u] did not accept message %zi (%m), kill it\n", worker->pid, count);
 407                         kill(worker->pid, SIGKILL);
 408                         worker->state = WORKER_KILLED;
 409                         continue;
 410                 }
 411                 worker_ref(worker);
 412                 worker->event = event;
 413                 worker->state = WORKER_RUNNING;
 414                 worker->event_start_usec = now_usec();
 415                 event->state = EVENT_RUNNING;
 416                 return;
 417         }
 418
 419         if (children >= children_max) {
 420                 if (children_max > 1)
 421                         log_debug("maximum number (%i) of children reached\n", children);
 422                 return;
 423         }
 424
 425         /* start new worker and pass initial device */
 426         worker_new(event);
 427 }
 428
 429 static int event_queue_insert(struct udev_device *dev)
 430 {
 431         struct event *event;
 432
 433         event = calloc(1, sizeof(struct event));
 434         if (event == NULL)
 435                 return -1;
 436
 437         event->udev = udev_device_get_udev(dev);
 438         event->dev = dev;
 439         event->seqnum = udev_device_get_seqnum(dev);
 440         event->devpath = udev_device_get_devpath(dev);
 441         event->devpath_len = strlen(event->devpath);
 442         event->devpath_old = udev_device_get_devpath_old(dev);
 443         event->devnum = udev_device_get_devnum(dev);
 444         event->is_block = (strcmp("block", udev_device_get_subsystem(dev)) == 0);
 445         event->ifindex = udev_device_get_ifindex(dev);
 446
 447         udev_queue_export_device_queued(udev_queue_export, dev);
 448         log_debug("seq %llu queued, '%s' '%s'\n", udev_device_get_seqnum(dev),
 449              udev_device_get_action(dev), udev_device_get_subsystem(dev));
 450
 451         event->state = EVENT_QUEUED;
 452         udev_list_node_append(&event->node, &event_list);
 453         return 0;
 454 }
 455
 456 static void worker_kill(struct udev *udev, int retain)
 457 {
 458         struct udev_list_node *loop;
 459         int max;
 460
 461         if (children <= retain)
 462                 return;
 463
 464         max = children - retain;
 465
 466         udev_list_node_foreach(loop, &worker_list) {
 467                 struct worker *worker = node_to_worker(loop);
 468
 469                 if (max-- <= 0)
 470                         break;
 471
 472                 if (worker->state == WORKER_KILLED)
 473                         continue;
 474
 475                 worker->state = WORKER_KILLED;
 476                 kill(worker->pid, SIGTERM);
 477         }
 478 }
 479
 480 /* lookup event for identical, parent, child device */
 481 static bool is_devpath_busy(struct event *event)
 482 {
 483         struct udev_list_node *loop;
 484         size_t common;
 485
 486         /* check if queue contains events we depend on */
 487         udev_list_node_foreach(loop, &event_list) {
 488                 struct event *loop_event = node_to_event(loop);
 489
 490                 /* we already found a later event, earlier can not block us, no need to check again */
 491                 if (loop_event->seqnum < event->delaying_seqnum)
 492                         continue;
 493
 494                 /* event we checked earlier still exists, no need to check again */
 495                 if (loop_event->seqnum == event->delaying_seqnum)
 496                         return true;
 497
 498                 /* found ourself, no later event can block us */
 499                 if (loop_event->seqnum >= event->seqnum)
 500                         break;
 501
 502                 /* check major/minor */
 503                 if (major(event->devnum) != 0 && event->devnum == loop_event->devnum && event->is_block == loop_event->is_block)
 504                         return true;
 505
 506                 /* check network device ifindex */
 507                 if (event->ifindex != 0 && event->ifindex == loop_event->ifindex)
 508                         return true;
 509
 510                 /* check our old name */
 511                 if (event->devpath_old != NULL && strcmp(loop_event->devpath, event->devpath_old) == 0) {
 512                         event->delaying_seqnum = loop_event->seqnum;
 513                         return true;
 514                 }
 515
 516                 /* compare devpath */
 517                 common = MIN(loop_event->devpath_len, event->devpath_len);
 518
 519                 /* one devpath is contained in the other? */
 520                 if (memcmp(loop_event->devpath, event->devpath, common) != 0)
 521                         continue;
 522
 523                 /* identical device event found */
 524                 if (loop_event->devpath_len == event->devpath_len) {
 525                         /* devices names might have changed/swapped in the meantime */
 526                         if (major(event->devnum) != 0 && (event->devnum != loop_event->devnum || event->is_block != loop_event->is_block))
 527                                 continue;
 528                         if (event->ifindex != 0 && event->ifindex != loop_event->ifindex)
 529                                 continue;
 530                         event->delaying_seqnum = loop_event->seqnum;
 531                         return true;
 532                 }
 533
 534                 /* parent device event found */
 535                 if (event->devpath[common] == '/') {
 536                         event->delaying_seqnum = loop_event->seqnum;
 537                         return true;
 538                 }
 539
 540                 /* child device event found */
 541                 if (loop_event->devpath[common] == '/') {
 542                         event->delaying_seqnum = loop_event->seqnum;
 543                         return true;
 544                 }
 545
 546                 /* no matching device */
 547                 continue;
 548         }
 549
 550         return false;
 551 }
 552
 553 static void event_queue_start(struct udev *udev)
 554 {
 555         struct udev_list_node *loop;
 556
 557         udev_list_node_foreach(loop, &event_list) {
 558                 struct event *event = node_to_event(loop);
 559
 560                 if (event->state != EVENT_QUEUED)
 561                         continue;
 562
 563                 /* do not start event if parent or child event is still running */
 564                 if (is_devpath_busy(event))
 565                         continue;
 566
 567                 event_run(event);
 568         }
 569 }
 570
 571 static void event_queue_cleanup(struct udev *udev, enum event_state match_type)
 572 {
 573         struct udev_list_node *loop, *tmp;
 574
 575         udev_list_node_foreach_safe(loop, tmp, &event_list) {
 576                 struct event *event = node_to_event(loop);
 577
 578                 if (match_type != EVENT_UNDEF && match_type != event->state)
 579                         continue;
 580
 581                 event_queue_delete(event, false);
 582         }
 583 }
 584
 585 static void worker_returned(int fd_worker)
 586 {
 587         for (;;) {
 588                 struct worker_message msg;
 589                 ssize_t size;
 590                 struct udev_list_node *loop;
 591
 592                 size = recv(fd_worker, &msg, sizeof(struct worker_message), MSG_DONTWAIT);
 593                 if (size != sizeof(struct worker_message))
 594                         break;
 595
 596                 /* lookup worker who sent the signal */
 597                 udev_list_node_foreach(loop, &worker_list) {
 598                         struct worker *worker = node_to_worker(loop);
 599
 600                         if (worker->pid != msg.pid)
 601                                 continue;
 602
 603                         /* worker returned */
 604                         if (worker->event) {
 605                                 worker->event->exitcode = msg.exitcode;
 606                                 event_queue_delete(worker->event, true);
 607                                 worker->event = NULL;
 608                         }
 609                         if (worker->state != WORKER_KILLED)
 610                                 worker->state = WORKER_IDLE;
 611                         worker_unref(worker);
 612                         break;
 613                 }
 614         }
 615 }
 616
 617 /* receive the udevd message from userspace */
 618 static struct udev_ctrl_connection *handle_ctrl_msg(struct udev_ctrl *uctrl)
 619 {
 620         struct udev *udev = udev_ctrl_get_udev(uctrl);
 621         struct udev_ctrl_connection *ctrl_conn;
 622         struct udev_ctrl_msg *ctrl_msg = NULL;
 623         const char *str;
 624         int i;
 625
 626         ctrl_conn = udev_ctrl_get_connection(uctrl);
 627         if (ctrl_conn == NULL)
 628                 goto out;
 629
 630         ctrl_msg = udev_ctrl_receive_msg(ctrl_conn);
 631         if (ctrl_msg == NULL)
 632                 goto out;
 633
 634         i = udev_ctrl_get_set_log_level(ctrl_msg);
 635         if (i >= 0) {
 636                 log_debug("udevd message (SET_LOG_PRIORITY) received, log_priority=%i\n", i);
 637                 log_set_max_level(i);
 638                 udev_set_log_priority(udev, i);
 639                 worker_kill(udev, 0);
 640         }
 641
 642         if (udev_ctrl_get_stop_exec_queue(ctrl_msg) > 0) {
 643                 log_debug("udevd message (STOP_EXEC_QUEUE) received\n");
 644                 stop_exec_queue = true;
 645         }
 646
 647         if (udev_ctrl_get_start_exec_queue(ctrl_msg) > 0) {
 648                 log_debug("udevd message (START_EXEC_QUEUE) received\n");
 649                 stop_exec_queue = false;
 650         }
 651
 652         if (udev_ctrl_get_reload(ctrl_msg) > 0) {
 653                 log_debug("udevd message (RELOAD) received\n");
 654                 reload = true;
 655         }
 656
 657         str = udev_ctrl_get_set_env(ctrl_msg);
 658         if (str != NULL) {
 659                 char *key;
 660
 661                 key = strdup(str);
 662                 if (key != NULL) {
 663                         char *val;
 664
 665                         val = strchr(key, '=');
 666                         if (val != NULL) {
 667                                 val[0] = '\0';
 668                                 val = &val[1];
 669                                 if (val[0] == '\0') {
 670                                         log_debug("udevd message (ENV) received, unset '%s'\n", key);
 671                                         udev_add_property(udev, key, NULL);
 672                                 } else {
 673                                         log_debug("udevd message (ENV) received, set '%s=%s'\n", key, val);
 674                                         udev_add_property(udev, key, val);
 675                                 }
 676                         } else {
 677                                 log_error("wrong key format '%s'\n", key);
 678                         }
 679                         free(key);
 680                 }
 681                 worker_kill(udev, 0);
 682         }
 683
 684         i = udev_ctrl_get_set_children_max(ctrl_msg);
 685         if (i >= 0) {
 686                 log_debug("udevd message (SET_MAX_CHILDREN) received, children_max=%i\n", i);
 687                 children_max = i;
 688         }
 689
 690         if (udev_ctrl_get_ping(ctrl_msg) > 0)
 691                 log_debug("udevd message (SYNC) received\n");
 692
 693         if (udev_ctrl_get_exit(ctrl_msg) > 0) {
 694                 log_debug("udevd message (EXIT) received\n");
 695                 udev_exit = true;
 696                 /* keep reference to block the client until we exit */
 697                 udev_ctrl_connection_ref(ctrl_conn);
 698         }
 699 out:
 700         udev_ctrl_msg_unref(ctrl_msg);
 701         return udev_ctrl_connection_unref(ctrl_conn);
 702 }
 703
 704 /* read inotify messages */
 705 static int handle_inotify(struct udev *udev)
 706 {
 707         int nbytes, pos;
 708         char *buf;
 709         struct inotify_event *ev;
 710
 711         if ((ioctl(fd_inotify, FIONREAD, &nbytes) < 0) || (nbytes <= 0))
 712                 return 0;
 713
 714         buf = malloc(nbytes);
 715         if (buf == NULL) {
 716                 log_error("error getting buffer for inotify\n");
 717                 return -1;
 718         }
 719
 720         nbytes = read(fd_inotify, buf, nbytes);
 721
 722         for (pos = 0; pos < nbytes; pos += sizeof(struct inotify_event) + ev->len) {
 723                 struct udev_device *dev;
 724
 725                 ev = (struct inotify_event *)(buf + pos);
 726                 dev = udev_watch_lookup(udev, ev->wd);
 727                 if (dev != NULL) {
 728                         log_debug("inotify event: %x for %s\n", ev->mask, udev_device_get_devnode(dev));
 729                         if (ev->mask & IN_CLOSE_WRITE) {
 730                                 char filename[UTIL_PATH_SIZE];
 731                                 int fd;
 732
 733                                 log_debug("device %s closed, synthesising 'change'\n", udev_device_get_devnode(dev));
 734                                 util_strscpyl(filename, sizeof(filename), udev_device_get_syspath(dev), "/uevent", NULL);
 735                                 fd = open(filename, O_WRONLY);
 736                                 if (fd >= 0) {
 737                                         if (write(fd, "change", 6) < 0)
 738                                                 log_debug("error writing uevent: %m\n");
 739                                         close(fd);
 740                                 }
 741                         }
 742                         if (ev->mask & IN_IGNORED)
 743                                 udev_watch_end(udev, dev);
 744
 745                         udev_device_unref(dev);
 746                 }
 747
 748         }
 749
 750         free(buf);
 751         return 0;
 752 }
 753
 754 static void handle_signal(struct udev *udev, int signo)
 755 {
 756         switch (signo) {
 757         case SIGINT:
 758         case SIGTERM:
 759                 udev_exit = true;
 760                 break;
 761         case SIGCHLD:
 762                 for (;;) {
 763                         pid_t pid;
 764                         int status;
 765                         struct udev_list_node *loop, *tmp;
 766
 767                         pid = waitpid(-1, &status, WNOHANG);
 768                         if (pid <= 0)
 769                                 break;
 770
 771                         udev_list_node_foreach_safe(loop, tmp, &worker_list) {
 772                                 struct worker *worker = node_to_worker(loop);
 773
 774                                 if (worker->pid != pid)
 775                                         continue;
 776                                 log_debug("worker [%u] exit\n", pid);
 777
 778                                 if (WIFEXITED(status)) {
 779                                         if (WEXITSTATUS(status) != 0)
 780                                                 log_error("worker [%u] exit with return code %i\n", pid, WEXITSTATUS(status));
 781                                 } else if (WIFSIGNALED(status)) {
 782                                         log_error("worker [%u] terminated by signal %i (%s)\n",
 783                                             pid, WTERMSIG(status), strsignal(WTERMSIG(status)));
 784                                 } else if (WIFSTOPPED(status)) {
 785                                         log_error("worker [%u] stopped\n", pid);
 786                                 } else if (WIFCONTINUED(status)) {
 787                                         log_error("worker [%u] continued\n", pid);
 788                                 } else {
 789                                         log_error("worker [%u] exit with status 0x%04x\n", pid, status);
 790                                 }
 791
 792                                 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
 793                                         if (worker->event) {
 794                                                 log_error("worker [%u] failed while handling '%s'\n",
 795                                                           pid, worker->event->devpath);
 796                                                 worker->event->exitcode = -32;
 797                                                 event_queue_delete(worker->event, true);
 798                                                 /* drop reference taken for state 'running' */
 799                                                 worker_unref(worker);
 800                                         }
 801                                 }
 802                                 worker_unref(worker);
 803                                 break;
 804                         }
 805                 }
 806                 break;
 807         case SIGHUP:
 808                 reload = true;
 809                 break;
 810         }
 811 }
 812
 813 static void static_dev_create_from_modules(struct udev *udev)
 814 {
 815         struct utsname kernel;
 816         char modules[UTIL_PATH_SIZE];
 817         char buf[4096];
 818         FILE *f;
 819
 820         uname(&kernel);
 821         util_strscpyl(modules, sizeof(modules), "/lib/modules/", kernel.release, "/modules.devname", NULL);
 822         f = fopen(modules, "r");
 823         if (f == NULL)
 824                 return;
 825
 826         while (fgets(buf, sizeof(buf), f) != NULL) {
 827                 char *s;
 828                 const char *modname;
 829                 const char *devname;
 830                 const char *devno;
 831                 int maj, min;
 832                 char type;
 833                 mode_t mode;
 834                 char filename[UTIL_PATH_SIZE];
 835
 836                 if (buf[0] == '#')
 837                         continue;
 838
 839                 modname = buf;
 840                 s = strchr(modname, ' ');
 841                 if (s == NULL)
 842                         continue;
 843                 s[0] = '\0';
 844
 845                 devname = &s[1];
 846                 s = strchr(devname, ' ');
 847                 if (s == NULL)
 848                         continue;
 849                 s[0] = '\0';
 850
 851                 devno = &s[1];
 852                 s = strchr(devno, ' ');
 853                 if (s == NULL)
 854                         s = strchr(devno, '\n');
 855                 if (s != NULL)
 856                         s[0] = '\0';
 857                 if (sscanf(devno, "%c%u:%u", &type, &maj, &min) != 3)
 858                         continue;
 859
 860                 if (type == 'c')
 861                         mode = S_IFCHR;
 862                 else if (type == 'b')
 863                         mode = S_IFBLK;
 864                 else
 865                         continue;
 866
 867                 util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/", devname, NULL);
 868                 util_create_path_selinux(udev, filename);
 869                 udev_selinux_setfscreatecon(udev, filename, mode);
 870                 log_debug("mknod '%s' %c%u:%u\n", filename, type, maj, min);
 871                 if (mknod(filename, mode, makedev(maj, min)) < 0 && errno == EEXIST)
 872                         utimensat(AT_FDCWD, filename, NULL, 0);
 873                 udev_selinux_resetfscreatecon(udev);
 874         }
 875
 876         fclose(f);
 877 }
 878
 879 /* needed for standalone udev operations */
 880 static void static_dev_create_links(struct udev *udev)
 881 {
 882         DIR *dir;
 883
 884         dir = opendir(udev_get_dev_path(udev));
 885         if (dir == NULL)
 886                 return;
 887
 888         struct stdlinks {
 889                 const char *link;
 890                 const char *target;
 891         };
 892         static const struct stdlinks stdlinks[] = {
 893                 { "core", "/proc/kcore" },
 894                 { "fd", "/proc/self/fd" },
 895                 { "stdin", "/proc/self/fd/0" },
 896                 { "stdout", "/proc/self/fd/1" },
 897                 { "stderr", "/proc/self/fd/2" },
 898         };
 899         unsigned int i;
 900
 901         for (i = 0; i < ARRAY_SIZE(stdlinks); i++) {
 902                 struct stat sb;
 903
 904                 if (stat(stdlinks[i].target, &sb) == 0) {
 905                         udev_selinux_setfscreateconat(udev, dirfd(dir), stdlinks[i].link, S_IFLNK);
 906                         if (symlinkat(stdlinks[i].target, dirfd(dir), stdlinks[i].link) < 0 && errno == EEXIST)
 907                                 utimensat(dirfd(dir), stdlinks[i].link, NULL, AT_SYMLINK_NOFOLLOW);
 908                         udev_selinux_resetfscreatecon(udev);
 909                 }
 910         }
 911
 912         closedir(dir);
 913 }
 914
 915 static int mem_size_mb(void)
 916 {
 917         FILE *f;
 918         char buf[4096];
 919         long int memsize = -1;
 920
 921         f = fopen("/proc/meminfo", "r");
 922         if (f == NULL)
 923                 return -1;
 924
 925         while (fgets(buf, sizeof(buf), f) != NULL) {
 926                 long int value;
 927
 928                 if (sscanf(buf, "MemTotal: %ld kB", &value) == 1) {
 929                         memsize = value / 1024;
 930                         break;
 931                 }
 932         }
 933
 934         fclose(f);
 935         return memsize;
 936 }
 937
 938 static int convert_db(struct udev *udev)
 939 {
 940         char filename[UTIL_PATH_SIZE];
 941         FILE *f;
 942         struct udev_enumerate *udev_enumerate;
 943         struct udev_list_entry *list_entry;
 944
 945         /* current database */
 946         util_strscpyl(filename, sizeof(filename), udev_get_run_path(udev), "/data", NULL);
 947         if (access(filename, F_OK) >= 0)
 948                 return 0;
 949
 950         /* make sure we do not get here again */
 951         util_create_path(udev, filename);
 952         mkdir(filename, 0755);
 953
 954         /* old database */
 955         util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/.udev/db", NULL);
 956         if (access(filename, F_OK) < 0)
 957                 return 0;
 958
 959         f = fopen("/dev/kmsg", "w");
 960         if (f != NULL) {
 961                 fprintf(f, "<30>udevd[%u]: converting old udev database\n", getpid());
 962                 fclose(f);
 963         }
 964
 965         udev_enumerate = udev_enumerate_new(udev);
 966         if (udev_enumerate == NULL)
 967                 return -1;
 968         udev_enumerate_scan_devices(udev_enumerate);
 969         udev_list_entry_foreach(list_entry, udev_enumerate_get_list_entry(udev_enumerate)) {
 970                 struct udev_device *device;
 971
 972                 device = udev_device_new_from_syspath(udev, udev_list_entry_get_name(list_entry));
 973                 if (device == NULL)
 974                         continue;
 975
 976                 /* try to find the old database for devices without a current one */
 977                 if (udev_device_read_db(device, NULL) < 0) {
 978                         bool have_db;
 979                         const char *id;
 980                         struct stat stats;
 981                         char devpath[UTIL_PATH_SIZE];
 982                         char from[UTIL_PATH_SIZE];
 983
 984                         have_db = false;
 985
 986                         /* find database in old location */
 987                         id = udev_device_get_id_filename(device);
 988                         util_strscpyl(from, sizeof(from), udev_get_dev_path(udev), "/.udev/db/", id, NULL);
 989                         if (lstat(from, &stats) == 0) {
 990                                 if (!have_db) {
 991                                         udev_device_read_db(device, from);
 992                                         have_db = true;
 993                                 }
 994                                 unlink(from);
 995                         }
 996
 997                         /* find old database with $subsys:$sysname name */
 998                         util_strscpyl(from, sizeof(from), udev_get_dev_path(udev),
 999                                      "/.udev/db/", udev_device_get_subsystem(device), ":",
1000                                      udev_device_get_sysname(device), NULL);
1001                         if (lstat(from, &stats) == 0) {
1002                                 if (!have_db) {
1003                                         udev_device_read_db(device, from);
1004                                         have_db = true;
1005                                 }
1006                                 unlink(from);
1007                         }
1008
1009                         /* find old database with the encoded devpath name */
1010                         util_path_encode(udev_device_get_devpath(device), devpath, sizeof(devpath));
1011                         util_strscpyl(from, sizeof(from), udev_get_dev_path(udev), "/.udev/db/", devpath, NULL);
1012                         if (lstat(from, &stats) == 0) {
1013                                 if (!have_db) {
1014                                         udev_device_read_db(device, from);
1015                                         have_db = true;
1016                                 }
1017                                 unlink(from);
1018                         }
1019
1020                         /* write out new database */
1021                         if (have_db)
1022                                 udev_device_update_db(device);
1023                 }
1024                 udev_device_unref(device);
1025         }
1026         udev_enumerate_unref(udev_enumerate);
1027         return 0;
1028 }
1029
1030 static int systemd_fds(struct udev *udev, int *rctrl, int *rnetlink)
1031 {
1032         int ctrl = -1, netlink = -1;
1033         int fd, n;
1034
1035         n = sd_listen_fds(true);
1036         if (n <= 0)
1037                 return -1;
1038
1039         for (fd = SD_LISTEN_FDS_START; fd < n + SD_LISTEN_FDS_START; fd++) {
1040                 if (sd_is_socket(fd, AF_LOCAL, SOCK_SEQPACKET, -1)) {
1041                         if (ctrl >= 0)
1042                                 return -1;
1043                         ctrl = fd;
1044                         continue;
1045                 }
1046
1047                 if (sd_is_socket(fd, AF_NETLINK, SOCK_RAW, -1)) {
1048                         if (netlink >= 0)
1049                                 return -1;
1050                         netlink = fd;
1051                         continue;
1052                 }
1053
1054                 return -1;
1055         }
1056
1057         if (ctrl < 0 || netlink < 0)
1058                 return -1;
1059
1060         log_debug("ctrl=%i netlink=%i\n", ctrl, netlink);
1061         *rctrl = ctrl;
1062         *rnetlink = netlink;
1063         return 0;
1064 }
1065
1066 static bool check_rules_timestamp(struct udev *udev)
1067 {
1068         char **p;
1069         unsigned long long *stamp_usec;
1070         int i, n;
1071         bool changed = false;
1072
1073         n = udev_get_rules_path(udev, &p, &stamp_usec);
1074         for (i = 0; i < n; i++) {
1075                 struct stat stats;
1076
1077                 if (stat(p[i], &stats) < 0)
1078                         continue;
1079
1080                 if (stamp_usec[i] == ts_usec(&stats.st_mtim))
1081                         continue;
1082
1083                 /* first check */
1084                 if (stamp_usec[i] != 0) {
1085                         log_debug("reload - timestamp of '%s' changed\n", p[i]);
1086                         changed = true;
1087                 }
1088
1089                 /* update timestamp */
1090                 stamp_usec[i] = ts_usec(&stats.st_mtim);
1091         }
1092
1093         return changed;
1094 }
1095
1096 int main(int argc, char *argv[])
1097 {
1098         struct udev *udev;
1099         FILE *f;
1100         sigset_t mask;
1101         int daemonize = false;
1102         int resolve_names = 1;
1103         static const struct option options[] = {
1104                 { "daemon", no_argument, NULL, 'd' },
1105                 { "debug", no_argument, NULL, 'D' },
1106                 { "children-max", required_argument, NULL, 'c' },
1107                 { "exec-delay", required_argument, NULL, 'e' },
1108                 { "resolve-names", required_argument, NULL, 'N' },
1109                 { "help", no_argument, NULL, 'h' },
1110                 { "version", no_argument, NULL, 'V' },
1111                 {}
1112         };
1113         int fd_ctrl = -1;
1114         int fd_netlink = -1;
1115         int fd_worker = -1;
1116         struct epoll_event ep_ctrl, ep_inotify, ep_signal, ep_netlink, ep_worker;
1117         struct udev_ctrl_connection *ctrl_conn = NULL;
1118         char **s;
1119         int rc = 1;
1120
1121         udev = udev_new();
1122         if (udev == NULL)
1123                 goto exit;
1124
1125         log_open();
1126         log_parse_environment();
1127         udev_set_log_fn(udev, udev_main_log);
1128         log_debug("version %s\n", VERSION);
1129         udev_selinux_init(udev);
1130
1131         for (;;) {
1132                 int option;
1133
1134                 option = getopt_long(argc, argv, "c:deDtN:hV", options, NULL);
1135                 if (option == -1)
1136                         break;
1137
1138                 switch (option) {
1139                 case 'd':
1140                         daemonize = true;
1141                         break;
1142                 case 'c':
1143                         children_max = strtoul(optarg, NULL, 0);
1144                         break;
1145                 case 'e':
1146                         exec_delay = strtoul(optarg, NULL, 0);
1147                         break;
1148                 case 'D':
1149                         debug = true;
1150                         if (udev_get_log_priority(udev) < LOG_INFO)
1151                                 udev_set_log_priority(udev, LOG_INFO);
1152                         break;
1153                 case 'N':
1154                         if (strcmp (optarg, "early") == 0) {
1155                                 resolve_names = 1;
1156                         } else if (strcmp (optarg, "late") == 0) {
1157                                 resolve_names = 0;
1158                         } else if (strcmp (optarg, "never") == 0) {
1159                                 resolve_names = -1;
1160                         } else {
1161                                 fprintf(stderr, "resolve-names must be early, late or never\n");
1162                                 log_error("resolve-names must be early, late or never\n");
1163                                 goto exit;
1164                         }
1165                         break;
1166                 case 'h':
1167                         printf("Usage: udevd OPTIONS\n"
1168                                "  --daemon\n"
1169                                "  --debug\n"
1170                                "  --children-max=<maximum number of workers>\n"
1171                                "  --exec-delay=<seconds to wait before executing RUN=>\n"
1172                                "  --resolve-names=early|late|never\n"
1173                                "  --version\n"
1174                                "  --help\n"
1175                                "\n");
1176                         goto exit;
1177                 case 'V':
1178                         printf("%s\n", VERSION);
1179                         goto exit;
1180                 default:
1181                         goto exit;
1182                 }
1183         }
1184
1185         /*
1186          * read the kernel commandline, in case we need to get into debug mode
1187          *   udev.log-priority=<level>              syslog priority
1188          *   udev.children-max=<number of workers>  events are fully serialized if set to 1
1189          *
1190          */
1191         f = fopen("/proc/cmdline", "r");
1192         if (f != NULL) {
1193                 char cmdline[4096];
1194
1195                 if (fgets(cmdline, sizeof(cmdline), f) != NULL) {
1196                         char *pos;
1197
1198                         pos = strstr(cmdline, "udev.log-priority=");
1199                         if (pos != NULL) {
1200                                 pos += strlen("udev.log-priority=");
1201                                 udev_set_log_priority(udev, util_log_priority(pos));
1202                         }
1203
1204                         pos = strstr(cmdline, "udev.children-max=");
1205                         if (pos != NULL) {
1206                                 pos += strlen("udev.children-max=");
1207                                 children_max = strtoul(pos, NULL, 0);
1208                         }
1209
1210                         pos = strstr(cmdline, "udev.exec-delay=");
1211                         if (pos != NULL) {
1212                                 pos += strlen("udev.exec-delay=");
1213                                 exec_delay = strtoul(pos, NULL, 0);
1214                         }
1215                 }
1216                 fclose(f);
1217         }
1218
1219         if (getuid() != 0) {
1220                 fprintf(stderr, "root privileges required\n");
1221                 log_error("root privileges required\n");
1222                 goto exit;
1223         }
1224
1225         /* set umask before creating any file/directory */
1226         chdir("/");
1227         umask(022);
1228
1229         /* /run/udev */
1230         mkdir(udev_get_run_path(udev), 0755);
1231
1232         /* create standard links, copy static nodes, create nodes from modules */
1233         static_dev_create_links(udev);
1234         static_dev_create_from_modules(udev);
1235
1236         /* before opening new files, make sure std{in,out,err} fds are in a sane state */
1237         if (daemonize) {
1238                 int fd;
1239
1240                 fd = open("/dev/null", O_RDWR);
1241                 if (fd >= 0) {
1242                         if (write(STDOUT_FILENO, 0, 0) < 0)
1243                                 dup2(fd, STDOUT_FILENO);
1244                         if (write(STDERR_FILENO, 0, 0) < 0)
1245                                 dup2(fd, STDERR_FILENO);
1246                         if (fd > STDERR_FILENO)
1247                                 close(fd);
1248                 } else {
1249                         fprintf(stderr, "cannot open /dev/null\n");
1250                         log_error("cannot open /dev/null\n");
1251                 }
1252         }
1253
1254         if (systemd_fds(udev, &fd_ctrl, &fd_netlink) >= 0) {
1255                 /* get control and netlink socket from from systemd */
1256                 udev_ctrl = udev_ctrl_new_from_fd(udev, fd_ctrl);
1257                 if (udev_ctrl == NULL) {
1258                         log_error("error taking over udev control socket");
1259                         rc = 1;
1260                         goto exit;
1261                 }
1262
1263                 monitor = udev_monitor_new_from_netlink_fd(udev, "kernel", fd_netlink);
1264                 if (monitor == NULL) {
1265                         log_error("error taking over netlink socket\n");
1266                         rc = 3;
1267                         goto exit;
1268                 }
1269         } else {
1270                 /* open control and netlink socket */
1271                 udev_ctrl = udev_ctrl_new(udev);
1272                 if (udev_ctrl == NULL) {
1273                         fprintf(stderr, "error initializing udev control socket");
1274                         log_error("error initializing udev control socket");
1275                         rc = 1;
1276                         goto exit;
1277                 }
1278                 fd_ctrl = udev_ctrl_get_fd(udev_ctrl);
1279
1280                 monitor = udev_monitor_new_from_netlink(udev, "kernel");
1281                 if (monitor == NULL) {
1282                         fprintf(stderr, "error initializing netlink socket\n");
1283                         log_error("error initializing netlink socket\n");
1284                         rc = 3;
1285                         goto exit;
1286                 }
1287                 fd_netlink = udev_monitor_get_fd(monitor);
1288         }
1289
1290         if (udev_monitor_enable_receiving(monitor) < 0) {
1291                 fprintf(stderr, "error binding netlink socket\n");
1292                 log_error("error binding netlink socket\n");
1293                 rc = 3;
1294                 goto exit;
1295         }
1296
1297         if (udev_ctrl_enable_receiving(udev_ctrl) < 0) {
1298                 fprintf(stderr, "error binding udev control socket\n");
1299                 log_error("error binding udev control socket\n");
1300                 rc = 1;
1301                 goto exit;
1302         }
1303
1304         udev_monitor_set_receive_buffer_size(monitor, 128*1024*1024);
1305
1306         /* create queue file before signalling 'ready', to make sure we block 'settle' */
1307         udev_queue_export = udev_queue_export_new(udev);
1308         if (udev_queue_export == NULL) {
1309                 log_error("error creating queue file\n");
1310                 goto exit;
1311         }
1312
1313         if (daemonize) {
1314                 pid_t pid;
1315                 int fd;
1316
1317                 pid = fork();
1318                 switch (pid) {
1319                 case 0:
1320                         break;
1321                 case -1:
1322                         log_error("fork of daemon failed: %m\n");
1323                         rc = 4;
1324                         goto exit;
1325                 default:
1326                         rc = EXIT_SUCCESS;
1327                         goto exit_daemonize;
1328                 }
1329
1330                 setsid();
1331
1332                 fd = open("/proc/self/oom_score_adj", O_RDWR);
1333                 if (fd < 0) {
1334                         /* Fallback to old interface */
1335                         fd = open("/proc/self/oom_adj", O_RDWR);
1336                         if (fd < 0) {
1337                                 log_error("error disabling OOM: %m\n");
1338                         } else {
1339                                 /* OOM_DISABLE == -17 */
1340                                 write(fd, "-17", 3);
1341                                 close(fd);
1342                         }
1343                 } else {
1344                         write(fd, "-1000", 5);
1345                         close(fd);
1346                 }
1347         } else {
1348                 sd_notify(1, "READY=1");
1349         }
1350
1351         f = fopen("/dev/kmsg", "w");
1352         if (f != NULL) {
1353                 fprintf(f, "<30>udevd[%u]: starting version " VERSION "\n", getpid());
1354                 fclose(f);
1355         }
1356
1357         if (!debug) {
1358                 int fd;
1359
1360                 fd = open("/dev/null", O_RDWR);
1361                 if (fd >= 0) {
1362                         dup2(fd, STDIN_FILENO);
1363                         dup2(fd, STDOUT_FILENO);
1364                         dup2(fd, STDERR_FILENO);
1365                         close(fd);
1366                 }
1367         }
1368
1369         fd_inotify = udev_watch_init(udev);
1370         if (fd_inotify < 0) {
1371                 fprintf(stderr, "error initializing inotify\n");
1372                 log_error("error initializing inotify\n");
1373                 rc = 4;
1374                 goto exit;
1375         }
1376         udev_watch_restore(udev);
1377
1378         /* block and listen to all signals on signalfd */
1379         sigfillset(&mask);
1380         sigprocmask(SIG_SETMASK, &mask, &sigmask_orig);
1381         fd_signal = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
1382         if (fd_signal < 0) {
1383                 fprintf(stderr, "error creating signalfd\n");
1384                 log_error("error creating signalfd\n");
1385                 rc = 5;
1386                 goto exit;
1387         }
1388
1389         /* unnamed socket from workers to the main daemon */
1390         if (socketpair(AF_LOCAL, SOCK_DGRAM|SOCK_CLOEXEC, 0, worker_watch) < 0) {
1391                 fprintf(stderr, "error creating socketpair\n");
1392                 log_error("error creating socketpair\n");
1393                 rc = 6;
1394                 goto exit;
1395         }
1396         fd_worker = worker_watch[READ_END];
1397
1398         udev_builtin_init(udev);
1399
1400         rules = udev_rules_new(udev, resolve_names);
1401         if (rules == NULL) {
1402                 log_error("error reading rules\n");
1403                 goto exit;
1404         }
1405
1406         memset(&ep_ctrl, 0, sizeof(struct epoll_event));
1407         ep_ctrl.events = EPOLLIN;
1408         ep_ctrl.data.fd = fd_ctrl;
1409
1410         memset(&ep_inotify, 0, sizeof(struct epoll_event));
1411         ep_inotify.events = EPOLLIN;
1412         ep_inotify.data.fd = fd_inotify;
1413
1414         memset(&ep_signal, 0, sizeof(struct epoll_event));
1415         ep_signal.events = EPOLLIN;
1416         ep_signal.data.fd = fd_signal;
1417
1418         memset(&ep_netlink, 0, sizeof(struct epoll_event));
1419         ep_netlink.events = EPOLLIN;
1420         ep_netlink.data.fd = fd_netlink;
1421
1422         memset(&ep_worker, 0, sizeof(struct epoll_event));
1423         ep_worker.events = EPOLLIN;
1424         ep_worker.data.fd = fd_worker;
1425
1426         fd_ep = epoll_create1(EPOLL_CLOEXEC);
1427         if (fd_ep < 0) {
1428                 log_error("error creating epoll fd: %m\n");
1429                 goto exit;
1430         }
1431         if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_ctrl, &ep_ctrl) < 0 ||
1432             epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_inotify, &ep_inotify) < 0 ||
1433             epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_signal, &ep_signal) < 0 ||
1434             epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_netlink, &ep_netlink) < 0 ||
1435             epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_worker, &ep_worker) < 0) {
1436                 log_error("fail to add fds to epoll: %m\n");
1437                 goto exit;
1438         }
1439
1440         /* if needed, convert old database from earlier udev version */
1441         convert_db(udev);
1442
1443         if (children_max <= 0) {
1444                 int memsize = mem_size_mb();
1445
1446                 /* set value depending on the amount of RAM */
1447                 if (memsize > 0)
1448                         children_max = 128 + (memsize / 8);
1449                 else
1450                         children_max = 128;
1451         }
1452         log_debug("set children_max to %u\n", children_max);
1453
1454         udev_rules_apply_static_dev_perms(rules);
1455
1456         udev_list_node_init(&event_list);
1457         udev_list_node_init(&worker_list);
1458
1459         for (;;) {
1460                 static unsigned long long last_usec;
1461                 struct epoll_event ev[8];
1462                 int fdcount;
1463                 int timeout;
1464                 bool is_worker, is_signal, is_inotify, is_netlink, is_ctrl;
1465                 int i;
1466
1467                 if (udev_exit) {
1468                         /* close sources of new events and discard buffered events */
1469                         if (fd_ctrl >= 0) {
1470                                 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_ctrl, NULL);
1471                                 fd_ctrl = -1;
1472                         }
1473                         if (monitor != NULL) {
1474                                 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_netlink, NULL);
1475                                 udev_monitor_unref(monitor);
1476                                 monitor = NULL;
1477                         }
1478                         if (fd_inotify >= 0) {
1479                                 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_inotify, NULL);
1480                                 close(fd_inotify);
1481                                 fd_inotify = -1;
1482                         }
1483
1484                         /* discard queued events and kill workers */
1485                         event_queue_cleanup(udev, EVENT_QUEUED);
1486                         worker_kill(udev, 0);
1487
1488                         /* exit after all has cleaned up */
1489                         if (udev_list_node_is_empty(&event_list) && udev_list_node_is_empty(&worker_list))
1490                                 break;
1491
1492                         /* timeout at exit for workers to finish */
1493                         timeout = 30 * 1000;
1494                 } else if (udev_list_node_is_empty(&event_list) && children <= 2) {
1495                         /* we are idle */
1496                         timeout = -1;
1497                 } else {
1498                         /* kill idle or hanging workers */
1499                         timeout = 3 * 1000;
1500                 }
1501                 fdcount = epoll_wait(fd_ep, ev, ARRAY_SIZE(ev), timeout);
1502                 if (fdcount < 0)
1503                         continue;
1504
1505                 if (fdcount == 0) {
1506                         struct udev_list_node *loop;
1507
1508                         /* timeout */
1509                         if (udev_exit) {
1510                                 log_error("timeout, giving up waiting for workers to finish\n");
1511                                 break;
1512                         }
1513
1514                         /* kill idle workers */
1515                         if (udev_list_node_is_empty(&event_list)) {
1516                                 log_debug("cleanup idle workers\n");
1517                                 worker_kill(udev, 2);
1518                         }
1519
1520                         /* check for hanging events */
1521                         udev_list_node_foreach(loop, &worker_list) {
1522                                 struct worker *worker = node_to_worker(loop);
1523
1524                                 if (worker->state != WORKER_RUNNING)
1525                                         continue;
1526
1527                                 if ((now_usec() - worker->event_start_usec) > 30 * 1000 * 1000) {
1528                                         log_error("worker [%u] timeout, kill it\n", worker->pid,
1529                                             worker->event ? worker->event->devpath : "<idle>");
1530                                         kill(worker->pid, SIGKILL);
1531                                         worker->state = WORKER_KILLED;
1532                                         /* drop reference taken for state 'running' */
1533                                         worker_unref(worker);
1534                                         if (worker->event) {
1535                                                 log_error("seq %llu '%s' killed\n",
1536                                                           udev_device_get_seqnum(worker->event->dev), worker->event->devpath);
1537                                                 worker->event->exitcode = -64;
1538                                                 event_queue_delete(worker->event, true);
1539                                                 worker->event = NULL;
1540                                         }
1541                                 }
1542                         }
1543
1544                 }
1545
1546                 is_worker = is_signal = is_inotify = is_netlink = is_ctrl = false;
1547                 for (i = 0; i < fdcount; i++) {
1548                         if (ev[i].data.fd == fd_worker && ev[i].events & EPOLLIN)
1549                                 is_worker = true;
1550                         else if (ev[i].data.fd == fd_netlink && ev[i].events & EPOLLIN)
1551                                 is_netlink = true;
1552                         else if (ev[i].data.fd == fd_signal && ev[i].events & EPOLLIN)
1553                                 is_signal = true;
1554                         else if (ev[i].data.fd == fd_inotify && ev[i].events & EPOLLIN)
1555                                 is_inotify = true;
1556                         else if (ev[i].data.fd == fd_ctrl && ev[i].events & EPOLLIN)
1557                                 is_ctrl = true;
1558                 }
1559
1560                 /* check for changed config, every 3 seconds at most */
1561                 if ((now_usec() - last_usec) > 3 * 1000 * 1000) {
1562                         if (check_rules_timestamp(udev))
1563                                 reload = true;
1564                         if (udev_builtin_validate(udev))
1565                                 reload = true;
1566
1567                         last_usec = now_usec();
1568                 }
1569
1570                 /* reload requested, HUP signal received, rules changed, builtin changed */
1571                 if (reload) {
1572                         worker_kill(udev, 0);
1573                         rules = udev_rules_unref(rules);
1574                         udev_builtin_exit(udev);
1575                         reload = 0;
1576                 }
1577
1578                 /* event has finished */
1579                 if (is_worker)
1580                         worker_returned(fd_worker);
1581
1582                 if (is_netlink) {
1583                         struct udev_device *dev;
1584
1585                         dev = udev_monitor_receive_device(monitor);
1586                         if (dev != NULL) {
1587                                 udev_device_set_usec_initialized(dev, now_usec());
1588                                 if (event_queue_insert(dev) < 0)
1589                                         udev_device_unref(dev);
1590                         }
1591                 }
1592
1593                 /* start new events */
1594                 if (!udev_list_node_is_empty(&event_list) && !udev_exit && !stop_exec_queue) {
1595                         if (rules == NULL)
1596                                 rules = udev_rules_new(udev, resolve_names);
1597                         if (rules != NULL)
1598                                 event_queue_start(udev);
1599                 }
1600
1601                 if (is_signal) {
1602                         struct signalfd_siginfo fdsi;
1603                         ssize_t size;
1604
1605                         size = read(fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
1606                         if (size == sizeof(struct signalfd_siginfo))
1607                                 handle_signal(udev, fdsi.ssi_signo);
1608                 }
1609
1610                 /* we are shutting down, the events below are not handled anymore */
1611                 if (udev_exit)
1612                         continue;
1613
1614                 /* device node watch */
1615                 if (is_inotify)
1616                         handle_inotify(udev);
1617
1618                 /*
1619                  * This needs to be after the inotify handling, to make sure,
1620                  * that the ping is send back after the possibly generated
1621                  * "change" events by the inotify device node watch.
1622                  *
1623                  * A single time we may receive a client connection which we need to
1624                  * keep open to block the client. It will be closed right before we
1625                  * exit.
1626                  */
1627                 if (is_ctrl)
1628                         ctrl_conn = handle_ctrl_msg(udev_ctrl);
1629         }
1630
1631         rc = EXIT_SUCCESS;
1632 exit:
1633         udev_queue_export_cleanup(udev_queue_export);
1634         udev_ctrl_cleanup(udev_ctrl);
1635 exit_daemonize:
1636         if (fd_ep >= 0)
1637                 close(fd_ep);
1638         worker_list_cleanup(udev);
1639         event_queue_cleanup(udev, EVENT_UNDEF);
1640         udev_rules_unref(rules);
1641         udev_builtin_exit(udev);
1642         if (fd_signal >= 0)
1643                 close(fd_signal);
1644         if (worker_watch[READ_END] >= 0)
1645                 close(worker_watch[READ_END]);
1646         if (worker_watch[WRITE_END] >= 0)
1647                 close(worker_watch[WRITE_END]);
1648         udev_monitor_unref(monitor);
1649         udev_queue_export_unref(udev_queue_export);
1650         udev_ctrl_connection_unref(ctrl_conn);
1651         udev_ctrl_unref(udev_ctrl);
1652         udev_selinux_exit(udev);
1653         udev_unref(udev);
1654         log_close();
1655         return rc;
1656 }