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core: make RuntimeDirectoryPreserve= works with non-service units
[thirdparty/systemd.git] / src / core / mount.c
1 /* SPDX-License-Identifier: LGPL-2.1+ */
2
3 #include <errno.h>
4 #include <signal.h>
5 #include <stdio.h>
6 #include <sys/epoll.h>
7
8 #include "sd-messages.h"
9
10 #include "alloc-util.h"
11 #include "dbus-mount.h"
12 #include "dbus-unit.h"
13 #include "device.h"
14 #include "exit-status.h"
15 #include "format-util.h"
16 #include "fstab-util.h"
17 #include "libmount-util.h"
18 #include "log.h"
19 #include "manager.h"
20 #include "mkdir.h"
21 #include "mount-setup.h"
22 #include "mount.h"
23 #include "mountpoint-util.h"
24 #include "parse-util.h"
25 #include "path-util.h"
26 #include "process-util.h"
27 #include "serialize.h"
28 #include "special.h"
29 #include "string-table.h"
30 #include "string-util.h"
31 #include "strv.h"
32 #include "unit-name.h"
33 #include "unit.h"
34
35 #define RETRY_UMOUNT_MAX 32
36
37 static const UnitActiveState state_translation_table[_MOUNT_STATE_MAX] = {
38 [MOUNT_DEAD] = UNIT_INACTIVE,
39 [MOUNT_MOUNTING] = UNIT_ACTIVATING,
40 [MOUNT_MOUNTING_DONE] = UNIT_ACTIVATING,
41 [MOUNT_MOUNTED] = UNIT_ACTIVE,
42 [MOUNT_REMOUNTING] = UNIT_RELOADING,
43 [MOUNT_UNMOUNTING] = UNIT_DEACTIVATING,
44 [MOUNT_REMOUNTING_SIGTERM] = UNIT_RELOADING,
45 [MOUNT_REMOUNTING_SIGKILL] = UNIT_RELOADING,
46 [MOUNT_UNMOUNTING_SIGTERM] = UNIT_DEACTIVATING,
47 [MOUNT_UNMOUNTING_SIGKILL] = UNIT_DEACTIVATING,
48 [MOUNT_FAILED] = UNIT_FAILED
49 };
50
51 static int mount_dispatch_timer(sd_event_source *source, usec_t usec, void *userdata);
52 static int mount_dispatch_io(sd_event_source *source, int fd, uint32_t revents, void *userdata);
53 static int mount_process_proc_self_mountinfo(Manager *m);
54
55 static bool MOUNT_STATE_WITH_PROCESS(MountState state) {
56 return IN_SET(state,
57 MOUNT_MOUNTING,
58 MOUNT_MOUNTING_DONE,
59 MOUNT_REMOUNTING,
60 MOUNT_REMOUNTING_SIGTERM,
61 MOUNT_REMOUNTING_SIGKILL,
62 MOUNT_UNMOUNTING,
63 MOUNT_UNMOUNTING_SIGTERM,
64 MOUNT_UNMOUNTING_SIGKILL);
65 }
66
67 static bool mount_is_network(const MountParameters *p) {
68 assert(p);
69
70 if (fstab_test_option(p->options, "_netdev\0"))
71 return true;
72
73 if (p->fstype && fstype_is_network(p->fstype))
74 return true;
75
76 return false;
77 }
78
79 static bool mount_is_loop(const MountParameters *p) {
80 assert(p);
81
82 if (fstab_test_option(p->options, "loop\0"))
83 return true;
84
85 return false;
86 }
87
88 static bool mount_is_bind(const MountParameters *p) {
89 assert(p);
90
91 if (fstab_test_option(p->options, "bind\0" "rbind\0"))
92 return true;
93
94 if (p->fstype && STR_IN_SET(p->fstype, "bind", "rbind"))
95 return true;
96
97 return false;
98 }
99
100 static bool mount_is_bound_to_device(const Mount *m) {
101 const MountParameters *p;
102
103 if (m->from_fragment)
104 return true;
105
106 p = &m->parameters_proc_self_mountinfo;
107 return fstab_test_option(p->options, "x-systemd.device-bound\0");
108 }
109
110 static bool mount_needs_quota(const MountParameters *p) {
111 assert(p);
112
113 /* Quotas are not enabled on network filesystems, but we want them, for example, on storage connected via
114 * iscsi. We hence don't use mount_is_network() here, as that would also return true for _netdev devices. */
115 if (p->fstype && fstype_is_network(p->fstype))
116 return false;
117
118 if (mount_is_bind(p))
119 return false;
120
121 return fstab_test_option(p->options,
122 "usrquota\0" "grpquota\0" "quota\0" "usrjquota\0" "grpjquota\0");
123 }
124
125 static void mount_init(Unit *u) {
126 Mount *m = MOUNT(u);
127
128 assert(u);
129 assert(u->load_state == UNIT_STUB);
130
131 m->timeout_usec = u->manager->default_timeout_start_usec;
132
133 m->exec_context.std_output = u->manager->default_std_output;
134 m->exec_context.std_error = u->manager->default_std_error;
135
136 m->directory_mode = 0755;
137
138 /* We need to make sure that /usr/bin/mount is always called
139 * in the same process group as us, so that the autofs kernel
140 * side doesn't send us another mount request while we are
141 * already trying to comply its last one. */
142 m->exec_context.same_pgrp = true;
143
144 m->control_command_id = _MOUNT_EXEC_COMMAND_INVALID;
145
146 u->ignore_on_isolate = true;
147 }
148
149 static int mount_arm_timer(Mount *m, usec_t usec) {
150 int r;
151
152 assert(m);
153
154 if (m->timer_event_source) {
155 r = sd_event_source_set_time(m->timer_event_source, usec);
156 if (r < 0)
157 return r;
158
159 return sd_event_source_set_enabled(m->timer_event_source, SD_EVENT_ONESHOT);
160 }
161
162 if (usec == USEC_INFINITY)
163 return 0;
164
165 r = sd_event_add_time(
166 UNIT(m)->manager->event,
167 &m->timer_event_source,
168 CLOCK_MONOTONIC,
169 usec, 0,
170 mount_dispatch_timer, m);
171 if (r < 0)
172 return r;
173
174 (void) sd_event_source_set_description(m->timer_event_source, "mount-timer");
175
176 return 0;
177 }
178
179 static void mount_unwatch_control_pid(Mount *m) {
180 assert(m);
181
182 if (m->control_pid <= 0)
183 return;
184
185 unit_unwatch_pid(UNIT(m), m->control_pid);
186 m->control_pid = 0;
187 }
188
189 static void mount_parameters_done(MountParameters *p) {
190 assert(p);
191
192 p->what = mfree(p->what);
193 p->options = mfree(p->options);
194 p->fstype = mfree(p->fstype);
195 }
196
197 static void mount_done(Unit *u) {
198 Mount *m = MOUNT(u);
199
200 assert(m);
201
202 m->where = mfree(m->where);
203
204 mount_parameters_done(&m->parameters_proc_self_mountinfo);
205 mount_parameters_done(&m->parameters_fragment);
206
207 m->exec_runtime = exec_runtime_unref(m->exec_runtime, false);
208 exec_command_done_array(m->exec_command, _MOUNT_EXEC_COMMAND_MAX);
209 m->control_command = NULL;
210
211 dynamic_creds_unref(&m->dynamic_creds);
212
213 mount_unwatch_control_pid(m);
214
215 m->timer_event_source = sd_event_source_unref(m->timer_event_source);
216 }
217
218 _pure_ static MountParameters* get_mount_parameters_fragment(Mount *m) {
219 assert(m);
220
221 if (m->from_fragment)
222 return &m->parameters_fragment;
223
224 return NULL;
225 }
226
227 _pure_ static MountParameters* get_mount_parameters(Mount *m) {
228 assert(m);
229
230 if (m->from_proc_self_mountinfo)
231 return &m->parameters_proc_self_mountinfo;
232
233 return get_mount_parameters_fragment(m);
234 }
235
236 static int update_parameters_proc_self_mountinfo(
237 Mount *m,
238 const char *what,
239 const char *options,
240 const char *fstype) {
241
242 MountParameters *p;
243 int r, q, w;
244
245 p = &m->parameters_proc_self_mountinfo;
246
247 r = free_and_strdup(&p->what, what);
248 if (r < 0)
249 return r;
250
251 q = free_and_strdup(&p->options, options);
252 if (q < 0)
253 return q;
254
255 w = free_and_strdup(&p->fstype, fstype);
256 if (w < 0)
257 return w;
258
259 return r > 0 || q > 0 || w > 0;
260 }
261
262 static int mount_add_mount_dependencies(Mount *m) {
263 MountParameters *pm;
264 Unit *other;
265 Iterator i;
266 Set *s;
267 int r;
268
269 assert(m);
270
271 if (!path_equal(m->where, "/")) {
272 _cleanup_free_ char *parent = NULL;
273
274 /* Adds in links to other mount points that might lie further up in the hierarchy */
275
276 parent = dirname_malloc(m->where);
277 if (!parent)
278 return -ENOMEM;
279
280 r = unit_require_mounts_for(UNIT(m), parent, UNIT_DEPENDENCY_IMPLICIT);
281 if (r < 0)
282 return r;
283 }
284
285 /* Adds in dependencies to other mount points that might be needed for the source path (if this is a bind mount
286 * or a loop mount) to be available. */
287 pm = get_mount_parameters_fragment(m);
288 if (pm && pm->what &&
289 path_is_absolute(pm->what) &&
290 (mount_is_bind(pm) || mount_is_loop(pm) || !mount_is_network(pm))) {
291
292 r = unit_require_mounts_for(UNIT(m), pm->what, UNIT_DEPENDENCY_FILE);
293 if (r < 0)
294 return r;
295 }
296
297 /* Adds in dependencies to other units that use this path or paths further down in the hierarchy */
298 s = manager_get_units_requiring_mounts_for(UNIT(m)->manager, m->where);
299 SET_FOREACH(other, s, i) {
300
301 if (other->load_state != UNIT_LOADED)
302 continue;
303
304 if (other == UNIT(m))
305 continue;
306
307 r = unit_add_dependency(other, UNIT_AFTER, UNIT(m), true, UNIT_DEPENDENCY_PATH);
308 if (r < 0)
309 return r;
310
311 if (UNIT(m)->fragment_path) {
312 /* If we have fragment configuration, then make this dependency required */
313 r = unit_add_dependency(other, UNIT_REQUIRES, UNIT(m), true, UNIT_DEPENDENCY_PATH);
314 if (r < 0)
315 return r;
316 }
317 }
318
319 return 0;
320 }
321
322 static int mount_add_device_dependencies(Mount *m) {
323 UnitDependencyMask mask;
324 MountParameters *p;
325 UnitDependency dep;
326 int r;
327
328 assert(m);
329
330 p = get_mount_parameters(m);
331 if (!p)
332 return 0;
333
334 if (!p->what)
335 return 0;
336
337 if (mount_is_bind(p))
338 return 0;
339
340 if (!is_device_path(p->what))
341 return 0;
342
343 /* /dev/root is a really weird thing, it's not a real device,
344 * but just a path the kernel exports for the root file system
345 * specified on the kernel command line. Ignore it here. */
346 if (path_equal(p->what, "/dev/root"))
347 return 0;
348
349 if (path_equal(m->where, "/"))
350 return 0;
351
352 /* Mount units from /proc/self/mountinfo are not bound to devices
353 * by default since they're subject to races when devices are
354 * unplugged. But the user can still force this dep with an
355 * appropriate option (or udev property) so the mount units are
356 * automatically stopped when the device disappears suddenly. */
357 dep = mount_is_bound_to_device(m) ? UNIT_BINDS_TO : UNIT_REQUIRES;
358
359 /* We always use 'what' from /proc/self/mountinfo if mounted */
360 mask = m->from_proc_self_mountinfo ? UNIT_DEPENDENCY_MOUNTINFO_IMPLICIT : UNIT_DEPENDENCY_FILE;
361
362 r = unit_add_node_dependency(UNIT(m), p->what, false, dep, mask);
363 if (r < 0)
364 return r;
365
366 return 0;
367 }
368
369 static int mount_add_quota_dependencies(Mount *m) {
370 UnitDependencyMask mask;
371 MountParameters *p;
372 int r;
373
374 assert(m);
375
376 if (!MANAGER_IS_SYSTEM(UNIT(m)->manager))
377 return 0;
378
379 p = get_mount_parameters_fragment(m);
380 if (!p)
381 return 0;
382
383 if (!mount_needs_quota(p))
384 return 0;
385
386 mask = m->from_fragment ? UNIT_DEPENDENCY_FILE : UNIT_DEPENDENCY_MOUNTINFO_IMPLICIT;
387
388 r = unit_add_two_dependencies_by_name(UNIT(m), UNIT_BEFORE, UNIT_WANTS, SPECIAL_QUOTACHECK_SERVICE, true, mask);
389 if (r < 0)
390 return r;
391
392 r = unit_add_two_dependencies_by_name(UNIT(m), UNIT_BEFORE, UNIT_WANTS, SPECIAL_QUOTAON_SERVICE, true, mask);
393 if (r < 0)
394 return r;
395
396 return 0;
397 }
398
399 static bool mount_is_extrinsic(Mount *m) {
400 MountParameters *p;
401 assert(m);
402
403 /* Returns true for all units that are "magic" and should be excluded from the usual start-up and shutdown
404 * dependencies. We call them "extrinsic" here, as they are generally mounted outside of the systemd dependency
405 * logic. We shouldn't attempt to manage them ourselves but it's fine if the user operates on them with us. */
406
407 if (!MANAGER_IS_SYSTEM(UNIT(m)->manager)) /* We only automatically manage mounts if we are in system mode */
408 return true;
409
410 if (PATH_IN_SET(m->where, /* Don't bother with the OS data itself */
411 "/",
412 "/usr"))
413 return true;
414
415 if (PATH_STARTSWITH_SET(m->where,
416 "/run/initramfs", /* This should stay around from before we boot until after we shutdown */
417 "/proc", /* All of this is API VFS */
418 "/sys", /* … dito … */
419 "/dev")) /* … dito … */
420 return true;
421
422 /* If this is an initrd mount, and we are not in the initrd, then leave this around forever, too. */
423 p = get_mount_parameters(m);
424 if (p && fstab_test_option(p->options, "x-initrd.mount\0") && !in_initrd())
425 return true;
426
427 return false;
428 }
429
430 static int mount_add_default_dependencies(Mount *m) {
431 const char *after, *before;
432 UnitDependencyMask mask;
433 MountParameters *p;
434 bool nofail;
435 int r;
436
437 assert(m);
438
439 if (!UNIT(m)->default_dependencies)
440 return 0;
441
442 /* We do not add any default dependencies to /, /usr or /run/initramfs/, since they are guaranteed to stay
443 * mounted the whole time, since our system is on it. Also, don't bother with anything mounted below virtual
444 * file systems, it's also going to be virtual, and hence not worth the effort. */
445 if (mount_is_extrinsic(m))
446 return 0;
447
448 p = get_mount_parameters(m);
449 if (!p)
450 return 0;
451
452 mask = m->from_fragment ? UNIT_DEPENDENCY_FILE : UNIT_DEPENDENCY_MOUNTINFO_DEFAULT;
453 nofail = m->from_fragment ? fstab_test_yes_no_option(m->parameters_fragment.options, "nofail\0" "fail\0") : false;
454
455 if (mount_is_network(p)) {
456 /* We order ourselves after network.target. This is
457 * primarily useful at shutdown: services that take
458 * down the network should order themselves before
459 * network.target, so that they are shut down only
460 * after this mount unit is stopped. */
461
462 r = unit_add_dependency_by_name(UNIT(m), UNIT_AFTER, SPECIAL_NETWORK_TARGET, true, mask);
463 if (r < 0)
464 return r;
465
466 /* We pull in network-online.target, and order
467 * ourselves after it. This is useful at start-up to
468 * actively pull in tools that want to be started
469 * before we start mounting network file systems, and
470 * whose purpose it is to delay this until the network
471 * is "up". */
472
473 r = unit_add_two_dependencies_by_name(UNIT(m), UNIT_WANTS, UNIT_AFTER, SPECIAL_NETWORK_ONLINE_TARGET, true, mask);
474 if (r < 0)
475 return r;
476
477 after = SPECIAL_REMOTE_FS_PRE_TARGET;
478 before = SPECIAL_REMOTE_FS_TARGET;
479 } else {
480 after = SPECIAL_LOCAL_FS_PRE_TARGET;
481 before = SPECIAL_LOCAL_FS_TARGET;
482 }
483
484 if (!nofail) {
485 r = unit_add_dependency_by_name(UNIT(m), UNIT_BEFORE, before, true, mask);
486 if (r < 0)
487 return r;
488 }
489
490 r = unit_add_dependency_by_name(UNIT(m), UNIT_AFTER, after, true, mask);
491 if (r < 0)
492 return r;
493
494 r = unit_add_two_dependencies_by_name(UNIT(m), UNIT_BEFORE, UNIT_CONFLICTS, SPECIAL_UMOUNT_TARGET, true, mask);
495 if (r < 0)
496 return r;
497
498 /* If this is a tmpfs mount then we have to unmount it before we try to deactivate swaps */
499 if (streq_ptr(p->fstype, "tmpfs")) {
500 r = unit_add_dependency_by_name(UNIT(m), UNIT_AFTER, SPECIAL_SWAP_TARGET, true, mask);
501 if (r < 0)
502 return r;
503 }
504
505 return 0;
506 }
507
508 static int mount_verify(Mount *m) {
509 _cleanup_free_ char *e = NULL;
510 MountParameters *p;
511 int r;
512
513 assert(m);
514
515 if (UNIT(m)->load_state != UNIT_LOADED)
516 return 0;
517
518 if (!m->from_fragment && !m->from_proc_self_mountinfo && !UNIT(m)->perpetual)
519 return -ENOENT;
520
521 r = unit_name_from_path(m->where, ".mount", &e);
522 if (r < 0)
523 return log_unit_error_errno(UNIT(m), r, "Failed to generate unit name from mount path: %m");
524
525 if (!unit_has_name(UNIT(m), e)) {
526 log_unit_error(UNIT(m), "Where= setting doesn't match unit name. Refusing.");
527 return -ENOEXEC;
528 }
529
530 if (mount_point_is_api(m->where) || mount_point_ignore(m->where)) {
531 log_unit_error(UNIT(m), "Cannot create mount unit for API file system %s. Refusing.", m->where);
532 return -ENOEXEC;
533 }
534
535 p = get_mount_parameters_fragment(m);
536 if (p && !p->what) {
537 log_unit_error(UNIT(m), "What= setting is missing. Refusing.");
538 return -ENOEXEC;
539 }
540
541 if (m->exec_context.pam_name && m->kill_context.kill_mode != KILL_CONTROL_GROUP) {
542 log_unit_error(UNIT(m), "Unit has PAM enabled. Kill mode must be set to control-group'. Refusing.");
543 return -ENOEXEC;
544 }
545
546 return 0;
547 }
548
549 static int mount_add_extras(Mount *m) {
550 Unit *u = UNIT(m);
551 int r;
552
553 assert(m);
554
555 /* Note: this call might be called after we already have been loaded once (and even when it has already been
556 * activated), in case data from /proc/self/mountinfo has changed. This means all code here needs to be ready
557 * to run with an already set up unit. */
558
559 if (u->fragment_path)
560 m->from_fragment = true;
561
562 if (!m->where) {
563 r = unit_name_to_path(u->id, &m->where);
564 if (r < 0)
565 return r;
566 }
567
568 path_simplify(m->where, false);
569
570 if (!u->description) {
571 r = unit_set_description(u, m->where);
572 if (r < 0)
573 return r;
574 }
575
576 r = mount_add_device_dependencies(m);
577 if (r < 0)
578 return r;
579
580 r = mount_add_mount_dependencies(m);
581 if (r < 0)
582 return r;
583
584 r = mount_add_quota_dependencies(m);
585 if (r < 0)
586 return r;
587
588 r = unit_patch_contexts(u);
589 if (r < 0)
590 return r;
591
592 r = unit_add_exec_dependencies(u, &m->exec_context);
593 if (r < 0)
594 return r;
595
596 r = unit_set_default_slice(u);
597 if (r < 0)
598 return r;
599
600 r = mount_add_default_dependencies(m);
601 if (r < 0)
602 return r;
603
604 return 0;
605 }
606
607 static int mount_load_root_mount(Unit *u) {
608 assert(u);
609
610 if (!unit_has_name(u, SPECIAL_ROOT_MOUNT))
611 return 0;
612
613 u->perpetual = true;
614 u->default_dependencies = false;
615
616 /* The stdio/kmsg bridge socket is on /, in order to avoid a dep loop, don't use kmsg logging for -.mount */
617 MOUNT(u)->exec_context.std_output = EXEC_OUTPUT_NULL;
618 MOUNT(u)->exec_context.std_input = EXEC_INPUT_NULL;
619
620 if (!u->description)
621 u->description = strdup("Root Mount");
622
623 return 1;
624 }
625
626 static int mount_load(Unit *u) {
627 Mount *m = MOUNT(u);
628 int r, q, w;
629
630 assert(u);
631 assert(u->load_state == UNIT_STUB);
632
633 r = mount_load_root_mount(u);
634
635 if (m->from_proc_self_mountinfo || u->perpetual)
636 q = unit_load_fragment_and_dropin_optional(u);
637 else
638 q = unit_load_fragment_and_dropin(u);
639
640 /* Add in some extras. Note we do this in all cases (even if we failed to load the unit) when announced by the
641 * kernel, because we need some things to be set up no matter what when the kernel establishes a mount and thus
642 * we need to update the state in our unit to track it. After all, consider that we don't allow changing the
643 * 'slice' field for a unit once it is active. */
644 if (u->load_state == UNIT_LOADED || m->from_proc_self_mountinfo || u->perpetual)
645 w = mount_add_extras(m);
646 else
647 w = 0;
648
649 if (r < 0)
650 return r;
651 if (q < 0)
652 return q;
653 if (w < 0)
654 return w;
655
656 return mount_verify(m);
657 }
658
659 static void mount_set_state(Mount *m, MountState state) {
660 MountState old_state;
661 assert(m);
662
663 if (m->state != state)
664 bus_unit_send_pending_change_signal(UNIT(m), false);
665
666 old_state = m->state;
667 m->state = state;
668
669 if (!MOUNT_STATE_WITH_PROCESS(state)) {
670 m->timer_event_source = sd_event_source_unref(m->timer_event_source);
671 mount_unwatch_control_pid(m);
672 m->control_command = NULL;
673 m->control_command_id = _MOUNT_EXEC_COMMAND_INVALID;
674 }
675
676 if (state != old_state)
677 log_unit_debug(UNIT(m), "Changed %s -> %s", mount_state_to_string(old_state), mount_state_to_string(state));
678
679 unit_notify(UNIT(m), state_translation_table[old_state], state_translation_table[state],
680 m->reload_result == MOUNT_SUCCESS ? 0 : UNIT_NOTIFY_RELOAD_FAILURE);
681 }
682
683 static int mount_coldplug(Unit *u) {
684 Mount *m = MOUNT(u);
685 MountState new_state = MOUNT_DEAD;
686 int r;
687
688 assert(m);
689 assert(m->state == MOUNT_DEAD);
690
691 if (m->deserialized_state != m->state)
692 new_state = m->deserialized_state;
693 else if (m->from_proc_self_mountinfo)
694 new_state = MOUNT_MOUNTED;
695
696 if (new_state == m->state)
697 return 0;
698
699 if (m->control_pid > 0 &&
700 pid_is_unwaited(m->control_pid) &&
701 MOUNT_STATE_WITH_PROCESS(new_state)) {
702
703 r = unit_watch_pid(UNIT(m), m->control_pid, false);
704 if (r < 0)
705 return r;
706
707 r = mount_arm_timer(m, usec_add(u->state_change_timestamp.monotonic, m->timeout_usec));
708 if (r < 0)
709 return r;
710 }
711
712 if (!IN_SET(new_state, MOUNT_DEAD, MOUNT_FAILED)) {
713 (void) unit_setup_dynamic_creds(u);
714 (void) unit_setup_exec_runtime(u);
715 }
716
717 mount_set_state(m, new_state);
718 return 0;
719 }
720
721 static void mount_dump(Unit *u, FILE *f, const char *prefix) {
722 char buf[FORMAT_TIMESPAN_MAX];
723 Mount *m = MOUNT(u);
724 MountParameters *p;
725
726 assert(m);
727 assert(f);
728
729 p = get_mount_parameters(m);
730
731 fprintf(f,
732 "%sMount State: %s\n"
733 "%sResult: %s\n"
734 "%sWhere: %s\n"
735 "%sWhat: %s\n"
736 "%sFile System Type: %s\n"
737 "%sOptions: %s\n"
738 "%sFrom /proc/self/mountinfo: %s\n"
739 "%sFrom fragment: %s\n"
740 "%sExtrinsic: %s\n"
741 "%sDirectoryMode: %04o\n"
742 "%sSloppyOptions: %s\n"
743 "%sLazyUnmount: %s\n"
744 "%sForceUnmount: %s\n"
745 "%sTimeoutSec: %s\n",
746 prefix, mount_state_to_string(m->state),
747 prefix, mount_result_to_string(m->result),
748 prefix, m->where,
749 prefix, p ? strna(p->what) : "n/a",
750 prefix, p ? strna(p->fstype) : "n/a",
751 prefix, p ? strna(p->options) : "n/a",
752 prefix, yes_no(m->from_proc_self_mountinfo),
753 prefix, yes_no(m->from_fragment),
754 prefix, yes_no(mount_is_extrinsic(m)),
755 prefix, m->directory_mode,
756 prefix, yes_no(m->sloppy_options),
757 prefix, yes_no(m->lazy_unmount),
758 prefix, yes_no(m->force_unmount),
759 prefix, format_timespan(buf, sizeof(buf), m->timeout_usec, USEC_PER_SEC));
760
761 if (m->control_pid > 0)
762 fprintf(f,
763 "%sControl PID: "PID_FMT"\n",
764 prefix, m->control_pid);
765
766 exec_context_dump(&m->exec_context, f, prefix);
767 kill_context_dump(&m->kill_context, f, prefix);
768 cgroup_context_dump(&m->cgroup_context, f, prefix);
769 }
770
771 static int mount_spawn(Mount *m, ExecCommand *c, pid_t *_pid) {
772
773 _cleanup_(exec_params_clear) ExecParameters exec_params = {
774 .flags = EXEC_APPLY_SANDBOXING|EXEC_APPLY_CHROOT|EXEC_APPLY_TTY_STDIN,
775 .stdin_fd = -1,
776 .stdout_fd = -1,
777 .stderr_fd = -1,
778 .exec_fd = -1,
779 };
780 pid_t pid;
781 int r;
782
783 assert(m);
784 assert(c);
785 assert(_pid);
786
787 r = unit_prepare_exec(UNIT(m));
788 if (r < 0)
789 return r;
790
791 r = mount_arm_timer(m, usec_add(now(CLOCK_MONOTONIC), m->timeout_usec));
792 if (r < 0)
793 return r;
794
795 r = unit_set_exec_params(UNIT(m), &exec_params);
796 if (r < 0)
797 return r;
798
799 r = exec_spawn(UNIT(m),
800 c,
801 &m->exec_context,
802 &exec_params,
803 m->exec_runtime,
804 &m->dynamic_creds,
805 &pid);
806 if (r < 0)
807 return r;
808
809 r = unit_watch_pid(UNIT(m), pid, true);
810 if (r < 0)
811 return r;
812
813 *_pid = pid;
814
815 return 0;
816 }
817
818 static void mount_enter_dead(Mount *m, MountResult f) {
819 assert(m);
820
821 if (m->result == MOUNT_SUCCESS)
822 m->result = f;
823
824 unit_log_result(UNIT(m), m->result == MOUNT_SUCCESS, mount_result_to_string(m->result));
825 mount_set_state(m, m->result != MOUNT_SUCCESS ? MOUNT_FAILED : MOUNT_DEAD);
826
827 m->exec_runtime = exec_runtime_unref(m->exec_runtime, true);
828
829 unit_destroy_runtime_directory(UNIT(m), &m->exec_context);
830
831 unit_unref_uid_gid(UNIT(m), true);
832
833 dynamic_creds_destroy(&m->dynamic_creds);
834
835 /* Any dependencies based on /proc/self/mountinfo are now stale */
836 unit_remove_dependencies(UNIT(m), UNIT_DEPENDENCY_MOUNTINFO_IMPLICIT);
837 }
838
839 static void mount_enter_mounted(Mount *m, MountResult f) {
840 assert(m);
841
842 if (m->result == MOUNT_SUCCESS)
843 m->result = f;
844
845 mount_set_state(m, MOUNT_MOUNTED);
846 }
847
848 static void mount_enter_dead_or_mounted(Mount *m, MountResult f) {
849 assert(m);
850
851 /* Enter DEAD or MOUNTED state, depending on what the kernel currently says about the mount point. We use this
852 * whenever we executed an operation, so that our internal state reflects what the kernel says again, after all
853 * ultimately we just mirror the kernel's internal state on this. */
854
855 if (m->from_proc_self_mountinfo)
856 mount_enter_mounted(m, f);
857 else
858 mount_enter_dead(m, f);
859 }
860
861 static int state_to_kill_operation(MountState state) {
862 switch (state) {
863
864 case MOUNT_REMOUNTING_SIGTERM:
865 case MOUNT_UNMOUNTING_SIGTERM:
866 return KILL_TERMINATE;
867
868 case MOUNT_REMOUNTING_SIGKILL:
869 case MOUNT_UNMOUNTING_SIGKILL:
870 return KILL_KILL;
871
872 default:
873 return _KILL_OPERATION_INVALID;
874 }
875 }
876
877 static void mount_enter_signal(Mount *m, MountState state, MountResult f) {
878 int r;
879
880 assert(m);
881
882 if (m->result == MOUNT_SUCCESS)
883 m->result = f;
884
885 r = unit_kill_context(
886 UNIT(m),
887 &m->kill_context,
888 state_to_kill_operation(state),
889 -1,
890 m->control_pid,
891 false);
892 if (r < 0)
893 goto fail;
894
895 if (r > 0) {
896 r = mount_arm_timer(m, usec_add(now(CLOCK_MONOTONIC), m->timeout_usec));
897 if (r < 0)
898 goto fail;
899
900 mount_set_state(m, state);
901 } else if (state == MOUNT_REMOUNTING_SIGTERM && m->kill_context.send_sigkill)
902 mount_enter_signal(m, MOUNT_REMOUNTING_SIGKILL, MOUNT_SUCCESS);
903 else if (IN_SET(state, MOUNT_REMOUNTING_SIGTERM, MOUNT_REMOUNTING_SIGKILL))
904 mount_enter_mounted(m, MOUNT_SUCCESS);
905 else if (state == MOUNT_UNMOUNTING_SIGTERM && m->kill_context.send_sigkill)
906 mount_enter_signal(m, MOUNT_UNMOUNTING_SIGKILL, MOUNT_SUCCESS);
907 else
908 mount_enter_dead_or_mounted(m, MOUNT_SUCCESS);
909
910 return;
911
912 fail:
913 log_unit_warning_errno(UNIT(m), r, "Failed to kill processes: %m");
914 mount_enter_dead_or_mounted(m, MOUNT_FAILURE_RESOURCES);
915 }
916
917 static void mount_enter_unmounting(Mount *m) {
918 int r;
919
920 assert(m);
921
922 /* Start counting our attempts */
923 if (!IN_SET(m->state,
924 MOUNT_UNMOUNTING,
925 MOUNT_UNMOUNTING_SIGTERM,
926 MOUNT_UNMOUNTING_SIGKILL))
927 m->n_retry_umount = 0;
928
929 m->control_command_id = MOUNT_EXEC_UNMOUNT;
930 m->control_command = m->exec_command + MOUNT_EXEC_UNMOUNT;
931
932 r = exec_command_set(m->control_command, UMOUNT_PATH, m->where, "-c", NULL);
933 if (r >= 0 && m->lazy_unmount)
934 r = exec_command_append(m->control_command, "-l", NULL);
935 if (r >= 0 && m->force_unmount)
936 r = exec_command_append(m->control_command, "-f", NULL);
937 if (r < 0)
938 goto fail;
939
940 mount_unwatch_control_pid(m);
941
942 r = mount_spawn(m, m->control_command, &m->control_pid);
943 if (r < 0)
944 goto fail;
945
946 mount_set_state(m, MOUNT_UNMOUNTING);
947
948 return;
949
950 fail:
951 log_unit_warning_errno(UNIT(m), r, "Failed to run 'umount' task: %m");
952 mount_enter_dead_or_mounted(m, MOUNT_FAILURE_RESOURCES);
953 }
954
955 static void mount_enter_mounting(Mount *m) {
956 int r;
957 MountParameters *p;
958
959 assert(m);
960
961 r = unit_fail_if_noncanonical(UNIT(m), m->where);
962 if (r < 0)
963 goto fail;
964
965 (void) mkdir_p_label(m->where, m->directory_mode);
966
967 unit_warn_if_dir_nonempty(UNIT(m), m->where);
968 unit_warn_leftover_processes(UNIT(m));
969
970 m->control_command_id = MOUNT_EXEC_MOUNT;
971 m->control_command = m->exec_command + MOUNT_EXEC_MOUNT;
972
973 /* Create the source directory for bind-mounts if needed */
974 p = get_mount_parameters_fragment(m);
975 if (p && mount_is_bind(p))
976 (void) mkdir_p_label(p->what, m->directory_mode);
977
978 if (p) {
979 _cleanup_free_ char *opts = NULL;
980
981 r = fstab_filter_options(p->options, "nofail\0" "noauto\0" "auto\0", NULL, NULL, &opts);
982 if (r < 0)
983 goto fail;
984
985 r = exec_command_set(m->control_command, MOUNT_PATH, p->what, m->where, NULL);
986 if (r >= 0 && m->sloppy_options)
987 r = exec_command_append(m->control_command, "-s", NULL);
988 if (r >= 0 && p->fstype)
989 r = exec_command_append(m->control_command, "-t", p->fstype, NULL);
990 if (r >= 0 && !isempty(opts))
991 r = exec_command_append(m->control_command, "-o", opts, NULL);
992 } else
993 r = -ENOENT;
994 if (r < 0)
995 goto fail;
996
997 mount_unwatch_control_pid(m);
998
999 r = mount_spawn(m, m->control_command, &m->control_pid);
1000 if (r < 0)
1001 goto fail;
1002
1003 mount_set_state(m, MOUNT_MOUNTING);
1004
1005 return;
1006
1007 fail:
1008 log_unit_warning_errno(UNIT(m), r, "Failed to run 'mount' task: %m");
1009 mount_enter_dead_or_mounted(m, MOUNT_FAILURE_RESOURCES);
1010 }
1011
1012 static void mount_set_reload_result(Mount *m, MountResult result) {
1013 assert(m);
1014
1015 /* Only store the first error we encounter */
1016 if (m->reload_result != MOUNT_SUCCESS)
1017 return;
1018
1019 m->reload_result = result;
1020 }
1021
1022 static void mount_enter_remounting(Mount *m) {
1023 int r;
1024 MountParameters *p;
1025
1026 assert(m);
1027
1028 /* Reset reload result when we are about to start a new remount operation */
1029 m->reload_result = MOUNT_SUCCESS;
1030
1031 m->control_command_id = MOUNT_EXEC_REMOUNT;
1032 m->control_command = m->exec_command + MOUNT_EXEC_REMOUNT;
1033
1034 p = get_mount_parameters_fragment(m);
1035 if (p) {
1036 const char *o;
1037
1038 if (p->options)
1039 o = strjoina("remount,", p->options);
1040 else
1041 o = "remount";
1042
1043 r = exec_command_set(m->control_command, MOUNT_PATH,
1044 p->what, m->where,
1045 "-o", o, NULL);
1046 if (r >= 0 && m->sloppy_options)
1047 r = exec_command_append(m->control_command, "-s", NULL);
1048 if (r >= 0 && p->fstype)
1049 r = exec_command_append(m->control_command, "-t", p->fstype, NULL);
1050 } else
1051 r = -ENOENT;
1052 if (r < 0)
1053 goto fail;
1054
1055 mount_unwatch_control_pid(m);
1056
1057 r = mount_spawn(m, m->control_command, &m->control_pid);
1058 if (r < 0)
1059 goto fail;
1060
1061 mount_set_state(m, MOUNT_REMOUNTING);
1062
1063 return;
1064
1065 fail:
1066 log_unit_warning_errno(UNIT(m), r, "Failed to run 'remount' task: %m");
1067 mount_set_reload_result(m, MOUNT_FAILURE_RESOURCES);
1068 mount_enter_dead_or_mounted(m, MOUNT_SUCCESS);
1069 }
1070
1071 static void mount_cycle_clear(Mount *m) {
1072 assert(m);
1073
1074 /* Clear all state we shall forget for this new cycle */
1075
1076 m->result = MOUNT_SUCCESS;
1077 m->reload_result = MOUNT_SUCCESS;
1078 exec_command_reset_status_array(m->exec_command, _MOUNT_EXEC_COMMAND_MAX);
1079 UNIT(m)->reset_accounting = true;
1080 }
1081
1082 static int mount_start(Unit *u) {
1083 Mount *m = MOUNT(u);
1084 int r;
1085
1086 assert(m);
1087
1088 /* We cannot fulfill this request right now, try again later
1089 * please! */
1090 if (IN_SET(m->state,
1091 MOUNT_UNMOUNTING,
1092 MOUNT_UNMOUNTING_SIGTERM,
1093 MOUNT_UNMOUNTING_SIGKILL))
1094 return -EAGAIN;
1095
1096 /* Already on it! */
1097 if (m->state == MOUNT_MOUNTING)
1098 return 0;
1099
1100 assert(IN_SET(m->state, MOUNT_DEAD, MOUNT_FAILED));
1101
1102 r = unit_test_start_limit(u);
1103 if (r < 0) {
1104 mount_enter_dead(m, MOUNT_FAILURE_START_LIMIT_HIT);
1105 return r;
1106 }
1107
1108 r = unit_acquire_invocation_id(u);
1109 if (r < 0)
1110 return r;
1111
1112 mount_cycle_clear(m);
1113 mount_enter_mounting(m);
1114
1115 return 1;
1116 }
1117
1118 static int mount_stop(Unit *u) {
1119 Mount *m = MOUNT(u);
1120
1121 assert(m);
1122
1123 switch (m->state) {
1124
1125 case MOUNT_UNMOUNTING:
1126 case MOUNT_UNMOUNTING_SIGKILL:
1127 case MOUNT_UNMOUNTING_SIGTERM:
1128 /* Already on it */
1129 return 0;
1130
1131 case MOUNT_MOUNTING:
1132 case MOUNT_MOUNTING_DONE:
1133 case MOUNT_REMOUNTING:
1134 /* If we are still waiting for /bin/mount, we go directly into kill mode. */
1135 mount_enter_signal(m, MOUNT_UNMOUNTING_SIGTERM, MOUNT_SUCCESS);
1136 return 0;
1137
1138 case MOUNT_REMOUNTING_SIGTERM:
1139 /* If we are already waiting for a hung remount, convert this to the matching unmounting state */
1140 mount_set_state(m, MOUNT_UNMOUNTING_SIGTERM);
1141 return 0;
1142
1143 case MOUNT_REMOUNTING_SIGKILL:
1144 /* as above */
1145 mount_set_state(m, MOUNT_UNMOUNTING_SIGKILL);
1146 return 0;
1147
1148 case MOUNT_MOUNTED:
1149 mount_enter_unmounting(m);
1150 return 1;
1151
1152 default:
1153 assert_not_reached("Unexpected state.");
1154 }
1155 }
1156
1157 static int mount_reload(Unit *u) {
1158 Mount *m = MOUNT(u);
1159
1160 assert(m);
1161 assert(m->state == MOUNT_MOUNTED);
1162
1163 mount_enter_remounting(m);
1164
1165 return 1;
1166 }
1167
1168 static int mount_serialize(Unit *u, FILE *f, FDSet *fds) {
1169 Mount *m = MOUNT(u);
1170
1171 assert(m);
1172 assert(f);
1173 assert(fds);
1174
1175 (void) serialize_item(f, "state", mount_state_to_string(m->state));
1176 (void) serialize_item(f, "result", mount_result_to_string(m->result));
1177 (void) serialize_item(f, "reload-result", mount_result_to_string(m->reload_result));
1178 (void) serialize_item_format(f, "n-retry-umount", "%u", m->n_retry_umount);
1179
1180 if (m->control_pid > 0)
1181 (void) serialize_item_format(f, "control-pid", PID_FMT, m->control_pid);
1182
1183 if (m->control_command_id >= 0)
1184 (void) serialize_item(f, "control-command", mount_exec_command_to_string(m->control_command_id));
1185
1186 return 0;
1187 }
1188
1189 static int mount_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) {
1190 Mount *m = MOUNT(u);
1191 int r;
1192
1193 assert(u);
1194 assert(key);
1195 assert(value);
1196 assert(fds);
1197
1198 if (streq(key, "state")) {
1199 MountState state;
1200
1201 if ((state = mount_state_from_string(value)) < 0)
1202 log_unit_debug(u, "Failed to parse state value: %s", value);
1203 else
1204 m->deserialized_state = state;
1205
1206 } else if (streq(key, "result")) {
1207 MountResult f;
1208
1209 f = mount_result_from_string(value);
1210 if (f < 0)
1211 log_unit_debug(u, "Failed to parse result value: %s", value);
1212 else if (f != MOUNT_SUCCESS)
1213 m->result = f;
1214
1215 } else if (streq(key, "reload-result")) {
1216 MountResult f;
1217
1218 f = mount_result_from_string(value);
1219 if (f < 0)
1220 log_unit_debug(u, "Failed to parse reload result value: %s", value);
1221 else if (f != MOUNT_SUCCESS)
1222 m->reload_result = f;
1223
1224 } else if (streq(key, "n-retry-umount")) {
1225
1226 r = safe_atou(value, &m->n_retry_umount);
1227 if (r < 0)
1228 log_unit_debug(u, "Failed to parse n-retry-umount value: %s", value);
1229
1230 } else if (streq(key, "control-pid")) {
1231
1232 if (parse_pid(value, &m->control_pid) < 0)
1233 log_unit_debug(u, "Failed to parse control-pid value: %s", value);
1234
1235 } else if (streq(key, "control-command")) {
1236 MountExecCommand id;
1237
1238 id = mount_exec_command_from_string(value);
1239 if (id < 0)
1240 log_unit_debug(u, "Failed to parse exec-command value: %s", value);
1241 else {
1242 m->control_command_id = id;
1243 m->control_command = m->exec_command + id;
1244 }
1245 } else
1246 log_unit_debug(u, "Unknown serialization key: %s", key);
1247
1248 return 0;
1249 }
1250
1251 _pure_ static UnitActiveState mount_active_state(Unit *u) {
1252 assert(u);
1253
1254 return state_translation_table[MOUNT(u)->state];
1255 }
1256
1257 _pure_ static const char *mount_sub_state_to_string(Unit *u) {
1258 assert(u);
1259
1260 return mount_state_to_string(MOUNT(u)->state);
1261 }
1262
1263 _pure_ static bool mount_may_gc(Unit *u) {
1264 Mount *m = MOUNT(u);
1265
1266 assert(m);
1267
1268 if (m->from_proc_self_mountinfo)
1269 return false;
1270
1271 return true;
1272 }
1273
1274 static void mount_sigchld_event(Unit *u, pid_t pid, int code, int status) {
1275 Mount *m = MOUNT(u);
1276 MountResult f;
1277
1278 assert(m);
1279 assert(pid >= 0);
1280
1281 if (pid != m->control_pid)
1282 return;
1283
1284 /* So here's the thing, we really want to know before /usr/bin/mount or /usr/bin/umount exit whether
1285 * they established/remove a mount. This is important when mounting, but even more so when unmounting
1286 * since we need to deal with nested mounts and otherwise cannot safely determine whether to repeat
1287 * the unmounts. In theory, the kernel fires /proc/self/mountinfo changes off before returning from
1288 * the mount() or umount() syscalls, and thus we should see the changes to the proc file before we
1289 * process the waitid() for the /usr/bin/(u)mount processes. However, this is unfortunately racy: we
1290 * have to waitid() for processes using P_ALL (since we need to reap unexpected children that got
1291 * reparented to PID 1), but when using P_ALL we might end up reaping processes that terminated just
1292 * instants ago, i.e. already after our last event loop iteration (i.e. after the last point we might
1293 * have noticed /proc/self/mountinfo events via epoll). This means event loop priorities for
1294 * processing SIGCHLD vs. /proc/self/mountinfo IO events are not as relevant as we want. To fix that
1295 * race, let's explicitly scan /proc/self/mountinfo before we start processing /usr/bin/(u)mount
1296 * dying. It's ugly, but it makes our ordering systematic again, and makes sure we always see
1297 * /proc/self/mountinfo changes before our mount/umount exits. */
1298 (void) mount_process_proc_self_mountinfo(u->manager);
1299
1300 m->control_pid = 0;
1301
1302 if (is_clean_exit(code, status, EXIT_CLEAN_COMMAND, NULL))
1303 f = MOUNT_SUCCESS;
1304 else if (code == CLD_EXITED)
1305 f = MOUNT_FAILURE_EXIT_CODE;
1306 else if (code == CLD_KILLED)
1307 f = MOUNT_FAILURE_SIGNAL;
1308 else if (code == CLD_DUMPED)
1309 f = MOUNT_FAILURE_CORE_DUMP;
1310 else
1311 assert_not_reached("Unknown code");
1312
1313 if (IN_SET(m->state, MOUNT_REMOUNTING, MOUNT_REMOUNTING_SIGKILL, MOUNT_REMOUNTING_SIGTERM))
1314 mount_set_reload_result(m, f);
1315 else if (m->result == MOUNT_SUCCESS)
1316 m->result = f;
1317
1318 if (m->control_command) {
1319 exec_status_exit(&m->control_command->exec_status, &m->exec_context, pid, code, status);
1320
1321 m->control_command = NULL;
1322 m->control_command_id = _MOUNT_EXEC_COMMAND_INVALID;
1323 }
1324
1325 unit_log_process_exit(
1326 u,
1327 "Mount process",
1328 mount_exec_command_to_string(m->control_command_id),
1329 f == MOUNT_SUCCESS,
1330 code, status);
1331
1332 /* Note that due to the io event priority logic, we can be sure the new mountinfo is loaded
1333 * before we process the SIGCHLD for the mount command. */
1334
1335 switch (m->state) {
1336
1337 case MOUNT_MOUNTING:
1338 /* Our mount point has not appeared in mountinfo. Something went wrong. */
1339
1340 if (f == MOUNT_SUCCESS) {
1341 /* Either /bin/mount has an unexpected definition of success,
1342 * or someone raced us and we lost. */
1343 log_unit_warning(UNIT(m), "Mount process finished, but there is no mount.");
1344 f = MOUNT_FAILURE_PROTOCOL;
1345 }
1346 mount_enter_dead(m, f);
1347 break;
1348
1349 case MOUNT_MOUNTING_DONE:
1350 mount_enter_mounted(m, f);
1351 break;
1352
1353 case MOUNT_REMOUNTING:
1354 case MOUNT_REMOUNTING_SIGTERM:
1355 case MOUNT_REMOUNTING_SIGKILL:
1356 mount_enter_dead_or_mounted(m, MOUNT_SUCCESS);
1357 break;
1358
1359 case MOUNT_UNMOUNTING:
1360
1361 if (f == MOUNT_SUCCESS && m->from_proc_self_mountinfo) {
1362
1363 /* Still a mount point? If so, let's try again. Most likely there were multiple mount points
1364 * stacked on top of each other. We might exceed the timeout specified by the user overall,
1365 * but we will stop as soon as any one umount times out. */
1366
1367 if (m->n_retry_umount < RETRY_UMOUNT_MAX) {
1368 log_unit_debug(u, "Mount still present, trying again.");
1369 m->n_retry_umount++;
1370 mount_enter_unmounting(m);
1371 } else {
1372 log_unit_warning(u, "Mount still present after %u attempts to unmount, giving up.", m->n_retry_umount);
1373 mount_enter_mounted(m, f);
1374 }
1375 } else
1376 mount_enter_dead_or_mounted(m, f);
1377
1378 break;
1379
1380 case MOUNT_UNMOUNTING_SIGKILL:
1381 case MOUNT_UNMOUNTING_SIGTERM:
1382 mount_enter_dead_or_mounted(m, f);
1383 break;
1384
1385 default:
1386 assert_not_reached("Uh, control process died at wrong time.");
1387 }
1388
1389 /* Notify clients about changed exit status */
1390 unit_add_to_dbus_queue(u);
1391 }
1392
1393 static int mount_dispatch_timer(sd_event_source *source, usec_t usec, void *userdata) {
1394 Mount *m = MOUNT(userdata);
1395
1396 assert(m);
1397 assert(m->timer_event_source == source);
1398
1399 switch (m->state) {
1400
1401 case MOUNT_MOUNTING:
1402 case MOUNT_MOUNTING_DONE:
1403 log_unit_warning(UNIT(m), "Mounting timed out. Terminating.");
1404 mount_enter_signal(m, MOUNT_UNMOUNTING_SIGTERM, MOUNT_FAILURE_TIMEOUT);
1405 break;
1406
1407 case MOUNT_REMOUNTING:
1408 log_unit_warning(UNIT(m), "Remounting timed out. Terminating remount process.");
1409 mount_set_reload_result(m, MOUNT_FAILURE_TIMEOUT);
1410 mount_enter_signal(m, MOUNT_REMOUNTING_SIGTERM, MOUNT_SUCCESS);
1411 break;
1412
1413 case MOUNT_REMOUNTING_SIGTERM:
1414 mount_set_reload_result(m, MOUNT_FAILURE_TIMEOUT);
1415
1416 if (m->kill_context.send_sigkill) {
1417 log_unit_warning(UNIT(m), "Remounting timed out. Killing.");
1418 mount_enter_signal(m, MOUNT_REMOUNTING_SIGKILL, MOUNT_SUCCESS);
1419 } else {
1420 log_unit_warning(UNIT(m), "Remounting timed out. Skipping SIGKILL. Ignoring.");
1421 mount_enter_dead_or_mounted(m, MOUNT_SUCCESS);
1422 }
1423 break;
1424
1425 case MOUNT_REMOUNTING_SIGKILL:
1426 mount_set_reload_result(m, MOUNT_FAILURE_TIMEOUT);
1427
1428 log_unit_warning(UNIT(m), "Mount process still around after SIGKILL. Ignoring.");
1429 mount_enter_dead_or_mounted(m, MOUNT_SUCCESS);
1430 break;
1431
1432 case MOUNT_UNMOUNTING:
1433 log_unit_warning(UNIT(m), "Unmounting timed out. Terminating.");
1434 mount_enter_signal(m, MOUNT_UNMOUNTING_SIGTERM, MOUNT_FAILURE_TIMEOUT);
1435 break;
1436
1437 case MOUNT_UNMOUNTING_SIGTERM:
1438 if (m->kill_context.send_sigkill) {
1439 log_unit_warning(UNIT(m), "Mount process timed out. Killing.");
1440 mount_enter_signal(m, MOUNT_UNMOUNTING_SIGKILL, MOUNT_FAILURE_TIMEOUT);
1441 } else {
1442 log_unit_warning(UNIT(m), "Mount process timed out. Skipping SIGKILL. Ignoring.");
1443 mount_enter_dead_or_mounted(m, MOUNT_FAILURE_TIMEOUT);
1444 }
1445 break;
1446
1447 case MOUNT_UNMOUNTING_SIGKILL:
1448 log_unit_warning(UNIT(m), "Mount process still around after SIGKILL. Ignoring.");
1449 mount_enter_dead_or_mounted(m, MOUNT_FAILURE_TIMEOUT);
1450 break;
1451
1452 default:
1453 assert_not_reached("Timeout at wrong time.");
1454 }
1455
1456 return 0;
1457 }
1458
1459 static int mount_setup_new_unit(
1460 Manager *m,
1461 const char *name,
1462 const char *what,
1463 const char *where,
1464 const char *options,
1465 const char *fstype,
1466 MountProcFlags *ret_flags,
1467 Unit **ret) {
1468
1469 _cleanup_(unit_freep) Unit *u = NULL;
1470 int r;
1471
1472 assert(m);
1473 assert(name);
1474 assert(ret_flags);
1475 assert(ret);
1476
1477 r = unit_new_for_name(m, sizeof(Mount), name, &u);
1478 if (r < 0)
1479 return r;
1480
1481 r = free_and_strdup(&u->source_path, "/proc/self/mountinfo");
1482 if (r < 0)
1483 return r;
1484
1485 r = free_and_strdup(&MOUNT(u)->where, where);
1486 if (r < 0)
1487 return r;
1488
1489 r = update_parameters_proc_self_mountinfo(MOUNT(u), what, options, fstype);
1490 if (r < 0)
1491 return r;
1492
1493 /* This unit was generated because /proc/self/mountinfo reported it. Remember this, so that by the time we load
1494 * the unit file for it (and thus add in extra deps right after) we know what source to attributes the deps
1495 * to.*/
1496 MOUNT(u)->from_proc_self_mountinfo = true;
1497
1498 /* We have only allocated the stub now, let's enqueue this unit for loading now, so that everything else is
1499 * loaded in now. */
1500 unit_add_to_load_queue(u);
1501
1502 *ret_flags = MOUNT_PROC_IS_MOUNTED | MOUNT_PROC_JUST_MOUNTED | MOUNT_PROC_JUST_CHANGED;
1503 *ret = TAKE_PTR(u);
1504 return 0;
1505 }
1506
1507 static int mount_setup_existing_unit(
1508 Unit *u,
1509 const char *what,
1510 const char *where,
1511 const char *options,
1512 const char *fstype,
1513 MountProcFlags *ret_flags) {
1514
1515 MountProcFlags flags = MOUNT_PROC_IS_MOUNTED;
1516 int r;
1517
1518 assert(u);
1519 assert(flags);
1520
1521 if (!MOUNT(u)->where) {
1522 MOUNT(u)->where = strdup(where);
1523 if (!MOUNT(u)->where)
1524 return -ENOMEM;
1525 }
1526
1527 r = update_parameters_proc_self_mountinfo(MOUNT(u), what, options, fstype);
1528 if (r < 0)
1529 return r;
1530 if (r > 0)
1531 flags |= MOUNT_PROC_JUST_CHANGED;
1532
1533 if (!MOUNT(u)->from_proc_self_mountinfo || FLAGS_SET(MOUNT(u)->proc_flags, MOUNT_PROC_JUST_MOUNTED))
1534 flags |= MOUNT_PROC_JUST_MOUNTED;
1535
1536 MOUNT(u)->from_proc_self_mountinfo = true;
1537
1538 if (IN_SET(u->load_state, UNIT_NOT_FOUND, UNIT_BAD_SETTING, UNIT_ERROR)) {
1539 /* The unit was previously not found or otherwise not loaded. Now that the unit shows up in
1540 * /proc/self/mountinfo we should reconsider it this, hence set it to UNIT_LOADED. */
1541 u->load_state = UNIT_LOADED;
1542 u->load_error = 0;
1543
1544 flags |= MOUNT_PROC_JUST_CHANGED;
1545 }
1546
1547 if (FLAGS_SET(flags, MOUNT_PROC_JUST_CHANGED)) {
1548 /* If things changed, then make sure that all deps are regenerated. Let's
1549 * first remove all automatic deps, and then add in the new ones. */
1550
1551 unit_remove_dependencies(u, UNIT_DEPENDENCY_MOUNTINFO_IMPLICIT);
1552
1553 r = mount_add_extras(MOUNT(u));
1554 if (r < 0)
1555 return r;
1556 }
1557
1558 *ret_flags = flags;
1559 return 0;
1560 }
1561
1562 static int mount_setup_unit(
1563 Manager *m,
1564 const char *what,
1565 const char *where,
1566 const char *options,
1567 const char *fstype,
1568 bool set_flags) {
1569
1570 _cleanup_free_ char *e = NULL;
1571 MountProcFlags flags;
1572 Unit *u;
1573 int r;
1574
1575 assert(m);
1576 assert(what);
1577 assert(where);
1578 assert(options);
1579 assert(fstype);
1580
1581 /* Ignore API mount points. They should never be referenced in
1582 * dependencies ever. */
1583 if (mount_point_is_api(where) || mount_point_ignore(where))
1584 return 0;
1585
1586 if (streq(fstype, "autofs"))
1587 return 0;
1588
1589 /* probably some kind of swap, ignore */
1590 if (!is_path(where))
1591 return 0;
1592
1593 r = unit_name_from_path(where, ".mount", &e);
1594 if (r < 0)
1595 return log_error_errno(r, "Failed to generate unit name from path '%s': %m", where);
1596
1597 u = manager_get_unit(m, e);
1598 if (u)
1599 r = mount_setup_existing_unit(u, what, where, options, fstype, &flags);
1600 else
1601 /* First time we see this mount point meaning that it's not been initiated by a mount unit but rather
1602 * by the sysadmin having called mount(8) directly. */
1603 r = mount_setup_new_unit(m, e, what, where, options, fstype, &flags, &u);
1604 if (r < 0)
1605 return log_warning_errno(r, "Failed to set up mount unit: %m");
1606
1607 /* If the mount changed properties or state, let's notify our clients */
1608 if (flags & (MOUNT_PROC_JUST_CHANGED|MOUNT_PROC_JUST_MOUNTED))
1609 unit_add_to_dbus_queue(u);
1610
1611 if (set_flags)
1612 MOUNT(u)->proc_flags = flags;
1613
1614 return 0;
1615 }
1616
1617 static int mount_load_proc_self_mountinfo(Manager *m, bool set_flags) {
1618 _cleanup_(mnt_free_tablep) struct libmnt_table *table = NULL;
1619 _cleanup_(mnt_free_iterp) struct libmnt_iter *iter = NULL;
1620 int r;
1621
1622 assert(m);
1623
1624 r = libmount_parse(NULL, NULL, &table, &iter);
1625 if (r < 0)
1626 return log_error_errno(r, "Failed to parse /proc/self/mountinfo: %m");
1627
1628 for (;;) {
1629 struct libmnt_fs *fs;
1630 const char *device, *path, *options, *fstype;
1631
1632 r = mnt_table_next_fs(table, iter, &fs);
1633 if (r == 1)
1634 break;
1635 if (r < 0)
1636 return log_error_errno(r, "Failed to get next entry from /proc/self/mountinfo: %m");
1637
1638 device = mnt_fs_get_source(fs);
1639 path = mnt_fs_get_target(fs);
1640 options = mnt_fs_get_options(fs);
1641 fstype = mnt_fs_get_fstype(fs);
1642
1643 if (!device || !path)
1644 continue;
1645
1646 device_found_node(m, device, DEVICE_FOUND_MOUNT, DEVICE_FOUND_MOUNT);
1647
1648 (void) mount_setup_unit(m, device, path, options, fstype, set_flags);
1649 }
1650
1651 return 0;
1652 }
1653
1654 static void mount_shutdown(Manager *m) {
1655 assert(m);
1656
1657 m->mount_event_source = sd_event_source_unref(m->mount_event_source);
1658
1659 mnt_unref_monitor(m->mount_monitor);
1660 m->mount_monitor = NULL;
1661 }
1662
1663 static int mount_get_timeout(Unit *u, usec_t *timeout) {
1664 Mount *m = MOUNT(u);
1665 usec_t t;
1666 int r;
1667
1668 if (!m->timer_event_source)
1669 return 0;
1670
1671 r = sd_event_source_get_time(m->timer_event_source, &t);
1672 if (r < 0)
1673 return r;
1674 if (t == USEC_INFINITY)
1675 return 0;
1676
1677 *timeout = t;
1678 return 1;
1679 }
1680
1681 static void mount_enumerate_perpetual(Manager *m) {
1682 Unit *u;
1683 int r;
1684
1685 assert(m);
1686
1687 /* Whatever happens, we know for sure that the root directory is around, and cannot go away. Let's
1688 * unconditionally synthesize it here and mark it as perpetual. */
1689
1690 u = manager_get_unit(m, SPECIAL_ROOT_MOUNT);
1691 if (!u) {
1692 r = unit_new_for_name(m, sizeof(Mount), SPECIAL_ROOT_MOUNT, &u);
1693 if (r < 0) {
1694 log_error_errno(r, "Failed to allocate the special " SPECIAL_ROOT_MOUNT " unit: %m");
1695 return;
1696 }
1697 }
1698
1699 u->perpetual = true;
1700 MOUNT(u)->deserialized_state = MOUNT_MOUNTED;
1701
1702 unit_add_to_load_queue(u);
1703 unit_add_to_dbus_queue(u);
1704 }
1705
1706 static bool mount_is_mounted(Mount *m) {
1707 assert(m);
1708
1709 return UNIT(m)->perpetual || FLAGS_SET(m->proc_flags, MOUNT_PROC_IS_MOUNTED);
1710 }
1711
1712 static void mount_enumerate(Manager *m) {
1713 int r;
1714
1715 assert(m);
1716
1717 mnt_init_debug(0);
1718
1719 if (!m->mount_monitor) {
1720 int fd;
1721
1722 m->mount_monitor = mnt_new_monitor();
1723 if (!m->mount_monitor) {
1724 log_oom();
1725 goto fail;
1726 }
1727
1728 r = mnt_monitor_enable_kernel(m->mount_monitor, 1);
1729 if (r < 0) {
1730 log_error_errno(r, "Failed to enable watching of kernel mount events: %m");
1731 goto fail;
1732 }
1733
1734 r = mnt_monitor_enable_userspace(m->mount_monitor, 1, NULL);
1735 if (r < 0) {
1736 log_error_errno(r, "Failed to enable watching of userspace mount events: %m");
1737 goto fail;
1738 }
1739
1740 /* mnt_unref_monitor() will close the fd */
1741 fd = r = mnt_monitor_get_fd(m->mount_monitor);
1742 if (r < 0) {
1743 log_error_errno(r, "Failed to acquire watch file descriptor: %m");
1744 goto fail;
1745 }
1746
1747 r = sd_event_add_io(m->event, &m->mount_event_source, fd, EPOLLIN, mount_dispatch_io, m);
1748 if (r < 0) {
1749 log_error_errno(r, "Failed to watch mount file descriptor: %m");
1750 goto fail;
1751 }
1752
1753 r = sd_event_source_set_priority(m->mount_event_source, SD_EVENT_PRIORITY_NORMAL-10);
1754 if (r < 0) {
1755 log_error_errno(r, "Failed to adjust mount watch priority: %m");
1756 goto fail;
1757 }
1758
1759 (void) sd_event_source_set_description(m->mount_event_source, "mount-monitor-dispatch");
1760 }
1761
1762 r = mount_load_proc_self_mountinfo(m, false);
1763 if (r < 0)
1764 goto fail;
1765
1766 return;
1767
1768 fail:
1769 mount_shutdown(m);
1770 }
1771
1772 static int drain_libmount(Manager *m) {
1773 bool rescan = false;
1774 int r;
1775
1776 assert(m);
1777
1778 /* Drain all events and verify that the event is valid.
1779 *
1780 * Note that libmount also monitors /run/mount mkdir if the directory does not exist yet. The mkdir
1781 * may generate event which is irrelevant for us.
1782 *
1783 * error: r < 0; valid: r == 0, false positive: r == 1 */
1784 do {
1785 r = mnt_monitor_next_change(m->mount_monitor, NULL, NULL);
1786 if (r < 0)
1787 return log_error_errno(r, "Failed to drain libmount events: %m");
1788 if (r == 0)
1789 rescan = true;
1790 } while (r == 0);
1791
1792 return rescan;
1793 }
1794
1795 static int mount_process_proc_self_mountinfo(Manager *m) {
1796 _cleanup_set_free_free_ Set *around = NULL, *gone = NULL;
1797 const char *what;
1798 Iterator i;
1799 Unit *u;
1800 int r;
1801
1802 assert(m);
1803
1804 r = drain_libmount(m);
1805 if (r <= 0)
1806 return r;
1807
1808 r = mount_load_proc_self_mountinfo(m, true);
1809 if (r < 0) {
1810 /* Reset flags, just in case, for later calls */
1811 LIST_FOREACH(units_by_type, u, m->units_by_type[UNIT_MOUNT])
1812 MOUNT(u)->proc_flags = 0;
1813
1814 return 0;
1815 }
1816
1817 manager_dispatch_load_queue(m);
1818
1819 LIST_FOREACH(units_by_type, u, m->units_by_type[UNIT_MOUNT]) {
1820 Mount *mount = MOUNT(u);
1821
1822 if (!mount_is_mounted(mount)) {
1823
1824 /* A mount point is not around right now. It
1825 * might be gone, or might never have
1826 * existed. */
1827
1828 if (mount->from_proc_self_mountinfo &&
1829 mount->parameters_proc_self_mountinfo.what) {
1830
1831 /* Remember that this device might just have disappeared */
1832 if (set_ensure_allocated(&gone, &path_hash_ops) < 0 ||
1833 set_put_strdup(gone, mount->parameters_proc_self_mountinfo.what) < 0)
1834 log_oom(); /* we don't care too much about OOM here... */
1835 }
1836
1837 mount->from_proc_self_mountinfo = false;
1838 assert_se(update_parameters_proc_self_mountinfo(mount, NULL, NULL, NULL) >= 0);
1839
1840 switch (mount->state) {
1841
1842 case MOUNT_MOUNTED:
1843 /* This has just been unmounted by somebody else, follow the state change. */
1844 mount_enter_dead(mount, MOUNT_SUCCESS);
1845 break;
1846
1847 default:
1848 break;
1849 }
1850
1851 } else if (mount->proc_flags & (MOUNT_PROC_JUST_MOUNTED|MOUNT_PROC_JUST_CHANGED)) {
1852
1853 /* A mount point was added or changed */
1854
1855 switch (mount->state) {
1856
1857 case MOUNT_DEAD:
1858 case MOUNT_FAILED:
1859
1860 /* This has just been mounted by somebody else, follow the state change, but let's
1861 * generate a new invocation ID for this implicitly and automatically. */
1862 (void) unit_acquire_invocation_id(u);
1863 mount_cycle_clear(mount);
1864 mount_enter_mounted(mount, MOUNT_SUCCESS);
1865 break;
1866
1867 case MOUNT_MOUNTING:
1868 mount_set_state(mount, MOUNT_MOUNTING_DONE);
1869 break;
1870
1871 default:
1872 /* Nothing really changed, but let's
1873 * issue an notification call
1874 * nonetheless, in case somebody is
1875 * waiting for this. (e.g. file system
1876 * ro/rw remounts.) */
1877 mount_set_state(mount, mount->state);
1878 break;
1879 }
1880 }
1881
1882 if (mount_is_mounted(mount) &&
1883 mount->from_proc_self_mountinfo &&
1884 mount->parameters_proc_self_mountinfo.what) {
1885 /* Track devices currently used */
1886
1887 if (set_ensure_allocated(&around, &path_hash_ops) < 0 ||
1888 set_put_strdup(around, mount->parameters_proc_self_mountinfo.what) < 0)
1889 log_oom();
1890 }
1891
1892 /* Reset the flags for later calls */
1893 mount->proc_flags = 0;
1894 }
1895
1896 SET_FOREACH(what, gone, i) {
1897 if (set_contains(around, what))
1898 continue;
1899
1900 /* Let the device units know that the device is no longer mounted */
1901 device_found_node(m, what, 0, DEVICE_FOUND_MOUNT);
1902 }
1903
1904 return 0;
1905 }
1906
1907 static int mount_dispatch_io(sd_event_source *source, int fd, uint32_t revents, void *userdata) {
1908 Manager *m = userdata;
1909
1910 assert(m);
1911 assert(revents & EPOLLIN);
1912
1913 return mount_process_proc_self_mountinfo(m);
1914 }
1915
1916 static void mount_reset_failed(Unit *u) {
1917 Mount *m = MOUNT(u);
1918
1919 assert(m);
1920
1921 if (m->state == MOUNT_FAILED)
1922 mount_set_state(m, MOUNT_DEAD);
1923
1924 m->result = MOUNT_SUCCESS;
1925 m->reload_result = MOUNT_SUCCESS;
1926 }
1927
1928 static int mount_kill(Unit *u, KillWho who, int signo, sd_bus_error *error) {
1929 Mount *m = MOUNT(u);
1930
1931 assert(m);
1932
1933 return unit_kill_common(u, who, signo, -1, m->control_pid, error);
1934 }
1935
1936 static int mount_control_pid(Unit *u) {
1937 Mount *m = MOUNT(u);
1938
1939 assert(m);
1940
1941 return m->control_pid;
1942 }
1943
1944 static const char* const mount_exec_command_table[_MOUNT_EXEC_COMMAND_MAX] = {
1945 [MOUNT_EXEC_MOUNT] = "ExecMount",
1946 [MOUNT_EXEC_UNMOUNT] = "ExecUnmount",
1947 [MOUNT_EXEC_REMOUNT] = "ExecRemount",
1948 };
1949
1950 DEFINE_STRING_TABLE_LOOKUP(mount_exec_command, MountExecCommand);
1951
1952 static const char* const mount_result_table[_MOUNT_RESULT_MAX] = {
1953 [MOUNT_SUCCESS] = "success",
1954 [MOUNT_FAILURE_RESOURCES] = "resources",
1955 [MOUNT_FAILURE_TIMEOUT] = "timeout",
1956 [MOUNT_FAILURE_EXIT_CODE] = "exit-code",
1957 [MOUNT_FAILURE_SIGNAL] = "signal",
1958 [MOUNT_FAILURE_CORE_DUMP] = "core-dump",
1959 [MOUNT_FAILURE_START_LIMIT_HIT] = "start-limit-hit",
1960 [MOUNT_FAILURE_PROTOCOL] = "protocol",
1961 };
1962
1963 DEFINE_STRING_TABLE_LOOKUP(mount_result, MountResult);
1964
1965 const UnitVTable mount_vtable = {
1966 .object_size = sizeof(Mount),
1967 .exec_context_offset = offsetof(Mount, exec_context),
1968 .cgroup_context_offset = offsetof(Mount, cgroup_context),
1969 .kill_context_offset = offsetof(Mount, kill_context),
1970 .exec_runtime_offset = offsetof(Mount, exec_runtime),
1971 .dynamic_creds_offset = offsetof(Mount, dynamic_creds),
1972
1973 .sections =
1974 "Unit\0"
1975 "Mount\0"
1976 "Install\0",
1977 .private_section = "Mount",
1978
1979 .init = mount_init,
1980 .load = mount_load,
1981 .done = mount_done,
1982
1983 .coldplug = mount_coldplug,
1984
1985 .dump = mount_dump,
1986
1987 .start = mount_start,
1988 .stop = mount_stop,
1989 .reload = mount_reload,
1990
1991 .kill = mount_kill,
1992
1993 .serialize = mount_serialize,
1994 .deserialize_item = mount_deserialize_item,
1995
1996 .active_state = mount_active_state,
1997 .sub_state_to_string = mount_sub_state_to_string,
1998
1999 .will_restart = unit_will_restart_default,
2000
2001 .may_gc = mount_may_gc,
2002
2003 .sigchld_event = mount_sigchld_event,
2004
2005 .reset_failed = mount_reset_failed,
2006
2007 .control_pid = mount_control_pid,
2008
2009 .bus_vtable = bus_mount_vtable,
2010 .bus_set_property = bus_mount_set_property,
2011 .bus_commit_properties = bus_mount_commit_properties,
2012
2013 .get_timeout = mount_get_timeout,
2014
2015 .can_transient = true,
2016
2017 .enumerate_perpetual = mount_enumerate_perpetual,
2018 .enumerate = mount_enumerate,
2019 .shutdown = mount_shutdown,
2020
2021 .status_message_formats = {
2022 .starting_stopping = {
2023 [0] = "Mounting %s...",
2024 [1] = "Unmounting %s...",
2025 },
2026 .finished_start_job = {
2027 [JOB_DONE] = "Mounted %s.",
2028 [JOB_FAILED] = "Failed to mount %s.",
2029 [JOB_TIMEOUT] = "Timed out mounting %s.",
2030 },
2031 .finished_stop_job = {
2032 [JOB_DONE] = "Unmounted %s.",
2033 [JOB_FAILED] = "Failed unmounting %s.",
2034 [JOB_TIMEOUT] = "Timed out unmounting %s.",
2035 },
2036 },
2037 };
Unnamed repository; edit this file 'description' to name the repository.