From 23d24b76f3df765fa6dbe7fe815bd4f8e76c9bb5 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Zbigniew=20J=C4=99drzejewski-Szmek?= Date: Mon, 8 Mar 2021 11:28:19 +0100 Subject: [PATCH 1/3] homed: wrap some very long lines --- src/home/homed-manager.c | 24 +++++++++++++++++------- 1 file changed, 17 insertions(+), 7 deletions(-) diff --git a/src/home/homed-manager.c b/src/home/homed-manager.c index f0c844b0cb..fd0be1d56f 100644 --- a/src/home/homed-manager.c +++ b/src/home/homed-manager.c @@ -100,7 +100,9 @@ static void manager_watch_home(Manager *m) { m->scan_slash_home = true; - r = sd_event_add_inotify(m->event, &m->inotify_event_source, "/home/", IN_CREATE|IN_CLOSE_WRITE|IN_DELETE_SELF|IN_MOVE_SELF|IN_ONLYDIR|IN_MOVED_TO|IN_MOVED_FROM|IN_DELETE, on_home_inotify, m); + r = sd_event_add_inotify(m->event, &m->inotify_event_source, "/home/", + IN_CREATE|IN_CLOSE_WRITE|IN_DELETE_SELF|IN_MOVE_SELF|IN_ONLYDIR|IN_MOVED_TO|IN_MOVED_FROM|IN_DELETE, + on_home_inotify, m); if (r < 0) log_full_errno(r == -ENOENT ? LOG_DEBUG : LOG_WARNING, r, "Failed to create inotify watch on /home/, ignoring."); @@ -368,7 +370,9 @@ static int manager_add_home_by_record( return r; if (!streq_ptr(hr->user_name, name)) - return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Identity's user name %s does not match file name %s, refusing.", hr->user_name, name); + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), + "Identity's user name %s does not match file name %s, refusing.", + hr->user_name, name); is_signed = manager_verify_user_record(m, hr); switch (is_signed) { @@ -599,19 +603,22 @@ static int manager_acquire_uid( other = hashmap_get(m->homes_by_uid, UID_TO_PTR(candidate)); if (other) { - log_debug("Candidate UID " UID_FMT " already used by another home directory (%s), let's try another.", candidate, other->user_name); + log_debug("Candidate UID " UID_FMT " already used by another home directory (%s), let's try another.", + candidate, other->user_name); continue; } pw = getpwuid(candidate); if (pw) { - log_debug("Candidate UID " UID_FMT " already registered by another user in NSS (%s), let's try another.", candidate, pw->pw_name); + log_debug("Candidate UID " UID_FMT " already registered by another user in NSS (%s), let's try another.", + candidate, pw->pw_name); continue; } gr = getgrgid((gid_t) candidate); if (gr) { - log_debug("Candidate UID " UID_FMT " already registered by another group in NSS (%s), let's try another.", candidate, gr->gr_name); + log_debug("Candidate UID " UID_FMT " already registered by another group in NSS (%s), let's try another.", + candidate, gr->gr_name); continue; } @@ -619,7 +626,8 @@ static int manager_acquire_uid( if (r < 0) continue; if (r > 0) { - log_debug_errno(r, "Candidate UID " UID_FMT " already owns IPC objects, let's try another: %m", candidate); + log_debug_errno(r, "Candidate UID " UID_FMT " already owns IPC objects, let's try another: %m", + candidate); continue; } @@ -692,7 +700,9 @@ static int manager_add_home_by_image( if (h && uid_is_valid(h->uid)) uid = h->uid; else { - r = manager_acquire_uid(m, start_uid, user_name, IN_SET(storage, USER_SUBVOLUME, USER_DIRECTORY, USER_FSCRYPT) ? image_path : NULL, &uid); + r = manager_acquire_uid(m, start_uid, user_name, + IN_SET(storage, USER_SUBVOLUME, USER_DIRECTORY, USER_FSCRYPT) ? image_path : NULL, + &uid); if (r < 0) return log_warning_errno(r, "Failed to acquire unused UID for %s: %m", user_name); } From cf5366387b24633284ee92285ea64a282270d591 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Zbigniew=20J=C4=99drzejewski-Szmek?= Date: Mon, 8 Mar 2021 11:37:17 +0100 Subject: [PATCH 2/3] homed: disable event sources before unreffing them C.f. 9793530228. We'd crash when trying to access an already-deallocated object: Thread no. 1 (7 frames) #2 log_assert_failed_realm at ../src/basic/log.c:844 #3 event_inotify_data_drop at ../src/libsystemd/sd-event/sd-event.c:3035 #4 source_dispatch at ../src/libsystemd/sd-event/sd-event.c:3250 #5 sd_event_dispatch at ../src/libsystemd/sd-event/sd-event.c:3631 #6 sd_event_run at ../src/libsystemd/sd-event/sd-event.c:3689 #7 sd_event_loop at ../src/libsystemd/sd-event/sd-event.c:3711 #8 run at ../src/home/homed.c:47 The source in question is an inotify source, and the messages are: systemd-homed[1340]: /home/ moved or renamed, recreating watch and rescanning. systemd-homed[1340]: Assertion '*_head == _item' failed at src/libsystemd/sd-event/sd-event.c:3035, function event_inotify_data_drop(). Aborting. on_home_inotify() got called, then manager_watch_home(), which unrefs the existing inotify_event_source. I assume that the source gets dispatched again because it was still in the pending queue. I can't reproduce the issue (timing?), but this should fix #17824, https://bugzilla.redhat.com/show_bug.cgi?id=1899264. --- src/home/homed-home-bus.c | 2 +- src/home/homed-home.c | 14 +++++++------- src/home/homed-manager-bus.c | 2 +- src/home/homed-manager.c | 6 +++--- 4 files changed, 12 insertions(+), 12 deletions(-) diff --git a/src/home/homed-home-bus.c b/src/home/homed-home-bus.c index 5643a9a6e4..2a58ecbc1a 100644 --- a/src/home/homed-home-bus.c +++ b/src/home/homed-home-bus.c @@ -885,7 +885,7 @@ static int on_deferred_change(sd_event_source *s, void *userdata) { assert(h); - h->deferred_change_event_source = sd_event_source_unref(h->deferred_change_event_source); + h->deferred_change_event_source = sd_event_source_disable_unref(h->deferred_change_event_source); r = bus_home_path(h, &path); if (r < 0) { diff --git a/src/home/homed-home.c b/src/home/homed-home.c index f1db828ed0..5a777e88ef 100644 --- a/src/home/homed-home.c +++ b/src/home/homed-home.c @@ -188,17 +188,17 @@ Home *home_free(Home *h) { user_record_unref(h->record); user_record_unref(h->secret); - h->worker_event_source = sd_event_source_unref(h->worker_event_source); + h->worker_event_source = sd_event_source_disable_unref(h->worker_event_source); safe_close(h->worker_stdout_fd); free(h->user_name); free(h->sysfs); - h->ref_event_source_please_suspend = sd_event_source_unref(h->ref_event_source_please_suspend); - h->ref_event_source_dont_suspend = sd_event_source_unref(h->ref_event_source_dont_suspend); + h->ref_event_source_please_suspend = sd_event_source_disable_unref(h->ref_event_source_please_suspend); + h->ref_event_source_dont_suspend = sd_event_source_disable_unref(h->ref_event_source_dont_suspend); h->pending_operations = ordered_set_free(h->pending_operations); - h->pending_event_source = sd_event_source_unref(h->pending_event_source); - h->deferred_change_event_source = sd_event_source_unref(h->deferred_change_event_source); + h->pending_event_source = sd_event_source_disable_unref(h->pending_event_source); + h->deferred_change_event_source = sd_event_source_disable_unref(h->deferred_change_event_source); h->current_operation = operation_unref(h->current_operation); @@ -888,7 +888,7 @@ static int home_on_worker_process(sd_event_source *s, const siginfo_t *si, void (void) hashmap_remove_value(h->manager->homes_by_worker_pid, PID_TO_PTR(h->worker_pid), h); h->worker_pid = 0; - h->worker_event_source = sd_event_source_unref(h->worker_event_source); + h->worker_event_source = sd_event_source_disable_unref(h->worker_event_source); if (si->si_code != CLD_EXITED) { assert(IN_SET(si->si_code, CLD_KILLED, CLD_DUMPED)); @@ -1067,7 +1067,7 @@ static int home_start_work(Home *h, const char *verb, UserRecord *hr, UserRecord r = hashmap_put(h->manager->homes_by_worker_pid, PID_TO_PTR(pid), h); if (r < 0) { - h->worker_event_source = sd_event_source_unref(h->worker_event_source); + h->worker_event_source = sd_event_source_disable_unref(h->worker_event_source); return r; } diff --git a/src/home/homed-manager-bus.c b/src/home/homed-manager-bus.c index d3ac98f901..8a06bb62bf 100644 --- a/src/home/homed-manager-bus.c +++ b/src/home/homed-manager-bus.c @@ -860,7 +860,7 @@ static int on_deferred_auto_login(sd_event_source *s, void *userdata) { assert(m); - m->deferred_auto_login_event_source = sd_event_source_unref(m->deferred_auto_login_event_source); + m->deferred_auto_login_event_source = sd_event_source_disable_unref(m->deferred_auto_login_event_source); r = sd_bus_emit_properties_changed( m->bus, diff --git a/src/home/homed-manager.c b/src/home/homed-manager.c index fd0be1d56f..2cab414bb3 100644 --- a/src/home/homed-manager.c +++ b/src/home/homed-manager.c @@ -79,7 +79,7 @@ static void manager_watch_home(Manager *m) { assert(m); - m->inotify_event_source = sd_event_source_unref(m->inotify_event_source); + m->inotify_event_source = sd_event_source_disable_unref(m->inotify_event_source); m->scan_slash_home = false; if (statfs("/home/", &sfs) < 0) { @@ -1670,7 +1670,7 @@ static int on_deferred_rescan(sd_event_source *s, void *userdata) { assert(m); - m->deferred_rescan_event_source = sd_event_source_unref(m->deferred_rescan_event_source); + m->deferred_rescan_event_source = sd_event_source_disable_unref(m->deferred_rescan_event_source); manager_enumerate_devices(m); manager_enumerate_images(m); @@ -1708,7 +1708,7 @@ static int on_deferred_gc(sd_event_source *s, void *userdata) { assert(m); - m->deferred_gc_event_source = sd_event_source_unref(m->deferred_gc_event_source); + m->deferred_gc_event_source = sd_event_source_disable_unref(m->deferred_gc_event_source); manager_gc_images(m); return 0; From f76e564437ef3d8bb270f2e1ee19a5156b0d8b83 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Zbigniew=20J=C4=99drzejewski-Szmek?= Date: Mon, 8 Mar 2021 11:52:09 +0100 Subject: [PATCH 3/3] homed: unref the sd_event object after the sources Shouldn't make any difference, but let's first flush any pending messages, then unref the reference-counted stuff, and only at the end do the direct free calls. --- src/home/homed-manager.c | 27 +++++++++++++-------------- 1 file changed, 13 insertions(+), 14 deletions(-) diff --git a/src/home/homed-manager.c b/src/home/homed-manager.c index 2cab414bb3..85fdc88962 100644 --- a/src/home/homed-manager.c +++ b/src/home/homed-manager.c @@ -241,25 +241,24 @@ Manager* manager_free(Manager *m) { HASHMAP_FOREACH(h, m->homes_by_worker_pid) (void) home_wait_for_worker(h); + sd_bus_flush_close_unref(m->bus); + bus_verify_polkit_async_registry_free(m->polkit_registry); + + m->device_monitor = sd_device_monitor_unref(m->device_monitor); + + m->inotify_event_source = sd_event_source_unref(m->inotify_event_source); + m->notify_socket_event_source = sd_event_source_unref(m->notify_socket_event_source); + m->deferred_rescan_event_source = sd_event_source_unref(m->deferred_rescan_event_source); + m->deferred_gc_event_source = sd_event_source_unref(m->deferred_gc_event_source); + m->deferred_auto_login_event_source = sd_event_source_unref(m->deferred_auto_login_event_source); + + sd_event_unref(m->event); + hashmap_free(m->homes_by_uid); hashmap_free(m->homes_by_name); hashmap_free(m->homes_by_worker_pid); hashmap_free(m->homes_by_sysfs); - m->inotify_event_source = sd_event_source_unref(m->inotify_event_source); - - bus_verify_polkit_async_registry_free(m->polkit_registry); - - sd_bus_flush_close_unref(m->bus); - sd_event_unref(m->event); - - m->notify_socket_event_source = sd_event_source_unref(m->notify_socket_event_source); - m->device_monitor = sd_device_monitor_unref(m->device_monitor); - - m->deferred_rescan_event_source = sd_event_source_unref(m->deferred_rescan_event_source); - m->deferred_gc_event_source = sd_event_source_unref(m->deferred_gc_event_source); - m->deferred_auto_login_event_source = sd_event_source_unref(m->deferred_auto_login_event_source); - if (m->private_key) EVP_PKEY_free(m->private_key);