policy: fix owner-ship of specific_object in can_auto_connect()

NMPolicy:auto_activate_device() would wrongly not free the
specific_object, although it is documented as transfer-full.

The only implementation of can_auto_connect() that returned
a specific-object is NMDeviceWifi:can_auto_connect(). So, there
wasn't any actual bug or memory leak.

Fixes: 4c028c7cefd413df3c824658fc007a96f44b0c9b

5 files changed, 15 insertions, 7 deletions

diff --git a/src/devices/bluetooth/nm-device-bt.c b/src/devices/bluetooth/nm-device-bt.c
index 67ae15bc82..77b4c667b9 100644
--- a/src/devices/bluetooth/nm-device-bt.c
+++ b/src/devices/bluetooth/nm-device-bt.c
@@ -136,7 +136,9 @@ can_auto_connect (NMDevice *device,
 	NMDeviceBtPrivate *priv = NM_DEVICE_BT_GET_PRIVATE (device);
 	guint32 bt_type;
 
-	if (!NM_DEVICE_CLASS (nm_device_bt_parent_class)->can_auto_connect (device, connection, specific_object))
+	nm_assert (!specific_object || !*specific_object);
+
+	if (!NM_DEVICE_CLASS (nm_device_bt_parent_class)->can_auto_connect (device, connection, NULL))
 		return FALSE;
 
 	/* Can't auto-activate a DUN connection without ModemManager */
@@ -351,9 +353,9 @@ complete_connection (NMDevice *device,
 
 static void
 ppp_stats (NMModem *modem,
-		   guint32 in_bytes,
-		   guint32 out_bytes,
-		   gpointer user_data)
+           guint32 in_bytes,
+           guint32 out_bytes,
+           gpointer user_data)
 {
 	g_signal_emit (NM_DEVICE_BT (user_data), signals[PPP_STATS], 0, in_bytes, out_bytes);
 }
diff --git a/src/devices/nm-device.c b/src/devices/nm-device.c
index c7fc22e529..c6d5f87f6b 100644
--- a/src/devices/nm-device.c
+++ b/src/devices/nm-device.c
@@ -3191,6 +3191,8 @@ can_auto_connect (NMDevice *self,
 {
 	NMSettingConnection *s_con;
 
+	nm_assert (!specific_object || !*specific_object);
+
 	s_con = nm_connection_get_setting_connection (connection);
 	if (!nm_setting_connection_get_autoconnect (s_con))
 		return FALSE;
diff --git a/src/devices/wifi/nm-device-olpc-mesh.c b/src/devices/wifi/nm-device-olpc-mesh.c
index 77a963756d..32ebac3b74 100644
--- a/src/devices/wifi/nm-device-olpc-mesh.c
+++ b/src/devices/wifi/nm-device-olpc-mesh.c
@@ -103,6 +103,8 @@ can_auto_connect (NMDevice *device,
                   NMConnection *connection,
                   char **specific_object)
 {
+	nm_assert (!specific_object || !*specific_object);
+
 	return FALSE;
 }
 
diff --git a/src/devices/wifi/nm-device-wifi.c b/src/devices/wifi/nm-device-wifi.c
index e106c88a8a..f98a40be63 100644
--- a/src/devices/wifi/nm-device-wifi.c
+++ b/src/devices/wifi/nm-device-wifi.c
@@ -961,7 +961,9 @@ can_auto_connect (NMDevice *device,
 	const char *method, *mode;
 	guint64 timestamp = 0;
 
-	if (!NM_DEVICE_CLASS (nm_device_wifi_parent_class)->can_auto_connect (device, connection, specific_object))
+	nm_assert (!specific_object || !*specific_object);
+
+	if (!NM_DEVICE_CLASS (nm_device_wifi_parent_class)->can_auto_connect (device, connection, NULL))
 		return FALSE;
 
 	s_wifi = nm_connection_get_setting_wireless (connection);
@@ -988,7 +990,7 @@ can_auto_connect (NMDevice *device,
 	ap = find_first_compatible_ap (self, connection, FALSE);
 	if (ap) {
 		/* All good; connection is usable */
-		*specific_object = (char *) nm_exported_object_get_path (NM_EXPORTED_OBJECT (ap));
+		NM_SET_OUT (specific_object, g_strdup (nm_exported_object_get_path (NM_EXPORTED_OBJECT (ap))));
 		return TRUE;
 	}
 
diff --git a/src/nm-policy.c b/src/nm-policy.c
index 0e437d9d4c..7d34732051 100644
--- a/src/nm-policy.c
+++ b/src/nm-policy.c
@@ -672,7 +672,7 @@ auto_activate_device (gpointer user_data)
 	NMPolicy *self;
 	NMPolicyPrivate *priv;
 	NMSettingsConnection *best_connection;
-	char *specific_object = NULL;
+	gs_free char *specific_object = NULL;
 	GPtrArray *connections;
 	GSList *connection_list;
 	guint i;