systemd/0285-dbus-stash-the-subscriber-list-when-we-disconenct-fr.patch
Jan Macku eb5b3a87a8 systemd-257-8
Resolves: RHEL-71409, RHEL-75774
2025-02-14 10:09:33 +01:00

181 lines
6.9 KiB
Diff

From f4d3078bd16a814364e653c1e1c2e53af301f0e7 Mon Sep 17 00:00:00 2001
From: Ronan Pigott <ronan@rjp.ie>
Date: Thu, 28 Nov 2024 12:53:32 -0700
Subject: [PATCH] dbus: stash the subscriber list when we disconenct from the
bus
If we unexpectly disconnect from the bus, systemd would end up dropping
the list of subscribers, which breaks the ability of clients like logind
to monitor the state of units.
Stash the list of subscribers into the deserialized state in the event
of a disconnect so that when we recover we can renew the broken
subscriptions.
(cherry picked from commit 8402ca04d1a063c3d8a9e3d5c16df8bb8778ae98)
Resolves: RHEL-73780
---
src/core/dbus.c | 21 +++++++++++++++------
src/core/dbus.h | 2 +-
src/core/manager.c | 8 ++++----
src/shared/bus-util.c | 22 ++++++++++++++++++++++
src/shared/bus-util.h | 1 +
5 files changed, 43 insertions(+), 11 deletions(-)
diff --git a/src/core/dbus.c b/src/core/dbus.c
index 3f0f40e702..9abc35888d 100644
--- a/src/core/dbus.c
+++ b/src/core/dbus.c
@@ -860,6 +860,8 @@ int bus_init_api(Manager *m) {
if (r < 0)
return log_error_errno(r, "Failed to set up API bus: %m");
+ (void) bus_track_coldplug(bus, &m->subscribed, /* recursive= */ false, m->deserialized_subscribed);
+ m->deserialized_subscribed = strv_free(m->deserialized_subscribed);
m->api_bus = TAKE_PTR(bus);
return 0;
@@ -1004,8 +1006,17 @@ static void destroy_bus(Manager *m, sd_bus **bus) {
}
/* Get rid of tracked clients on this bus */
- if (m->subscribed && sd_bus_track_get_bus(m->subscribed) == *bus)
+ if (m->subscribed && sd_bus_track_get_bus(m->subscribed) == *bus) {
+ _cleanup_strv_free_ char **subscribed = NULL;
+ int r;
+
+ r = bus_track_to_strv(m->subscribed, &subscribed);
+ if (r < 0)
+ log_warning_errno(r, "Failed to serialize api subscribers, ignoring: %m");
+ strv_free_and_replace(m->deserialized_subscribed, subscribed);
+
m->subscribed = sd_bus_track_unref(m->subscribed);
+ }
HASHMAP_FOREACH(j, m->jobs)
if (j->bus_track && sd_bus_track_get_bus(j->bus_track) == *bus)
@@ -1064,7 +1075,6 @@ void bus_done(Manager *m) {
assert(!m->subscribed);
- m->deserialized_subscribed = strv_free(m->deserialized_subscribed);
m->polkit_registry = hashmap_free(m->polkit_registry);
}
@@ -1153,20 +1163,19 @@ void bus_track_serialize(sd_bus_track *t, FILE *f, const char *prefix) {
}
}
-int bus_track_coldplug(Manager *m, sd_bus_track **t, bool recursive, char **l) {
+int bus_track_coldplug(sd_bus *bus, sd_bus_track **t, bool recursive, char **l) {
int r;
- assert(m);
assert(t);
if (strv_isempty(l))
return 0;
- if (!m->api_bus)
+ if (!bus)
return 0;
if (!*t) {
- r = sd_bus_track_new(m->api_bus, t, NULL, NULL);
+ r = sd_bus_track_new(bus, t, NULL, NULL);
if (r < 0)
return r;
}
diff --git a/src/core/dbus.h b/src/core/dbus.h
index d00c14d3b7..eb1baf6049 100644
--- a/src/core/dbus.h
+++ b/src/core/dbus.h
@@ -19,7 +19,7 @@ void bus_done(Manager *m);
int bus_fdset_add_all(Manager *m, FDSet *fds);
void bus_track_serialize(sd_bus_track *t, FILE *f, const char *prefix);
-int bus_track_coldplug(Manager *m, sd_bus_track **t, bool recursive, char **l);
+int bus_track_coldplug(sd_bus *bus, sd_bus_track **t, bool recursive, char **l);
int bus_foreach_bus(Manager *m, sd_bus_track *subscribed2, int (*send_message)(sd_bus *bus, void *userdata), void *userdata);
diff --git a/src/core/manager.c b/src/core/manager.c
index 485fdd1a66..068ea2ab03 100644
--- a/src/core/manager.c
+++ b/src/core/manager.c
@@ -1803,6 +1803,9 @@ Manager* manager_free(Manager *m) {
free(m->switch_root);
free(m->switch_root_init);
+ sd_bus_track_unref(m->subscribed);
+ strv_free(m->deserialized_subscribed);
+
unit_defaults_done(&m->defaults);
FOREACH_ARRAY(map, m->units_needing_mounts_for, _UNIT_MOUNT_DEPENDENCY_TYPE_MAX) {
@@ -2139,7 +2142,7 @@ int manager_startup(Manager *m, FILE *serialization, FDSet *fds, const char *roo
manager_setup_bus(m);
/* Now that we are connected to all possible buses, let's deserialize who is tracking us. */
- r = bus_track_coldplug(m, &m->subscribed, false, m->deserialized_subscribed);
+ r = bus_track_coldplug(m->api_bus, &m->subscribed, false, m->deserialized_subscribed);
if (r < 0)
log_warning_errno(r, "Failed to deserialized tracked clients, ignoring: %m");
m->deserialized_subscribed = strv_free(m->deserialized_subscribed);
@@ -3813,9 +3816,6 @@ int manager_reload(Manager *m) {
/* Clean up runtime objects no longer referenced */
manager_vacuum(m);
- /* Clean up deserialized tracked clients */
- m->deserialized_subscribed = strv_free(m->deserialized_subscribed);
-
/* Consider the reload process complete now. */
assert(m->n_reloading > 0);
m->n_reloading--;
diff --git a/src/shared/bus-util.c b/src/shared/bus-util.c
index ff80e580fc..2cdde97b78 100644
--- a/src/shared/bus-util.c
+++ b/src/shared/bus-util.c
@@ -698,6 +698,28 @@ int bus_track_add_name_many(sd_bus_track *t, char **l) {
return r;
}
+int bus_track_to_strv(sd_bus_track *t, char ***ret) {
+ _cleanup_strv_free_ char **subscribed = NULL;
+ int r = 0;
+
+ assert(ret);
+
+ for (const char *n = sd_bus_track_first(t); n; n = sd_bus_track_next(t)) {
+ r = sd_bus_track_count_name(t, n);
+ if (r < 0)
+ return r;
+
+ for (int j = 0; j < r; j++) {
+ r = strv_extend(&subscribed, n);
+ if (r < 0)
+ return r;
+ }
+ }
+
+ *ret = TAKE_PTR(subscribed);
+ return r;
+}
+
int bus_open_system_watch_bind_with_description(sd_bus **ret, const char *description) {
_cleanup_(sd_bus_close_unrefp) sd_bus *bus = NULL;
const char *e;
diff --git a/src/shared/bus-util.h b/src/shared/bus-util.h
index fbccb24314..83522ad1c1 100644
--- a/src/shared/bus-util.h
+++ b/src/shared/bus-util.h
@@ -63,6 +63,7 @@ int bus_path_encode_unique(sd_bus *b, const char *prefix, const char *sender_id,
int bus_path_decode_unique(const char *path, const char *prefix, char **ret_sender, char **ret_external);
int bus_track_add_name_many(sd_bus_track *t, char **l);
+int bus_track_to_strv(sd_bus_track *t, char ***ret);
int bus_open_system_watch_bind_with_description(sd_bus **ret, const char *description);
static inline int bus_open_system_watch_bind(sd_bus **ret) {