systemd/1217-core-do-not-disconnect-from-bus-when-failed-to-insta.patch
Jan Macku 2169d2c18c systemd-252-57
Resolves: RHEL-108555,RHEL-108568,RHEL-108576,RHEL-108584,RHEL-108596,RHEL-108598,RHEL-109096,RHEL-109488,RHEL-111065,RHEL-31756,RHEL-50103
2025-09-16 08:59:46 +02:00

72 lines
2.8 KiB
Diff

From 899e94d72119c5e5f3d0ae75f39abd376bc28b0e Mon Sep 17 00:00:00 2001
From: Yu Watanabe <watanabe.yu+github@gmail.com>
Date: Sun, 29 Dec 2024 15:50:43 +0900
Subject: [PATCH] core: do not disconnect from bus when failed to install
signal match
If bus_add_match_full() is called without install callback and we failed
to install the signal match e.g. by timeout, then add_match_callback()
will disconnect from the bus.
Let's use a custom install handler and handle failures gracefully.
This does not *solve* the root cause of issue #30573, but should improve
the situation when the issue is triggered.
(cherry picked from commit db6b214f95aa42f9a9fa3d94a3c6492cc57b58fb)
Related: RHEL-31756
---
src/core/unit.c | 30 ++++++++++++++++++++++++++++--
1 file changed, 28 insertions(+), 2 deletions(-)
diff --git a/src/core/unit.c b/src/core/unit.c
index 5a091b3bc4..9e349402ff 100644
--- a/src/core/unit.c
+++ b/src/core/unit.c
@@ -3486,6 +3486,32 @@ int unit_load_related_unit(Unit *u, const char *type, Unit **_found) {
return r;
}
+static int signal_name_owner_changed_install_handler(sd_bus_message *message, void *userdata, sd_bus_error *error) {
+ Unit *u = ASSERT_PTR(userdata);
+ const sd_bus_error *e;
+ int r;
+
+ e = sd_bus_message_get_error(message);
+ if (!e) {
+ log_unit_trace(u, "Successfully installed NameOwnerChanged signal match.");
+ return 0;
+ }
+
+ r = sd_bus_error_get_errno(e);
+ log_unit_error_errno(u, r,
+ "Unexpected error response on installing NameOwnerChanged signal match: %s",
+ bus_error_message(e, r));
+
+ /* If we failed to install NameOwnerChanged signal, also unref the bus slot of GetNameOwner(). */
+ u->match_bus_slot = sd_bus_slot_unref(u->match_bus_slot);
+ u->get_name_owner_slot = sd_bus_slot_unref(u->get_name_owner_slot);
+
+ if (UNIT_VTABLE(u)->bus_name_owner_change)
+ UNIT_VTABLE(u)->bus_name_owner_change(u, NULL);
+
+ return 0;
+}
+
static int signal_name_owner_changed(sd_bus_message *message, void *userdata, sd_bus_error *error) {
const char *new_owner;
Unit *u = ASSERT_PTR(userdata);
@@ -3568,10 +3594,10 @@ int unit_install_bus_match(Unit *u, sd_bus *bus, const char *name) {
r = bus_add_match_full(
bus,
&u->match_bus_slot,
- true,
+ /* asynchronous = */ true,
match,
signal_name_owner_changed,
- NULL,
+ signal_name_owner_changed_install_handler,
u,
timeout_usec);
if (r < 0)