dbus: don't call bus_path_escape() with NULL unit name

Fixes an assertion triggerable via D-Bus.

https://bugzilla.redhat.com/show_bug.cgi?id=622008

2 files changed, 9 insertions, 0 deletions

diff --git a/src/dbus-unit.c b/src/dbus-unit.c
index d25f325013..c9ccac1472 100644
--- a/src/dbus-unit.c
+++ b/src/dbus-unit.c
@@ -434,6 +434,9 @@ void bus_unit_send_change_signal(Unit *u) {
                 u->meta.in_dbus_queue = false;
         }
 
+        if (!u->meta.id)
+                return;
+
         if (!bus_has_subscriber(u->meta.manager)) {
                 u->meta.sent_dbus_new_signal = true;
                 return;
@@ -491,6 +494,9 @@ void bus_unit_send_removed_signal(Unit *u) {
         if (!u->meta.sent_dbus_new_signal)
                 bus_unit_send_change_signal(u);
 
+        if (!u->meta.id)
+                return;
+
         if (!(p = unit_dbus_path(u)))
                 goto oom;
 
diff --git a/src/unit.c b/src/unit.c
index 840c1d1fc4..dd665e2d5a 100644
--- a/src/unit.c
+++ b/src/unit.c
@@ -1551,6 +1551,9 @@ char *unit_dbus_path(Unit *u) {
 
         assert(u);
 
+        if (!u->meta.id)
+                return NULL;
+
         if (!(e = bus_path_escape(u->meta.id)))
                 return NULL;