manager: change autoconnect-slaves logic for already active slaves

Autoconnect-slaves currently forces an activation of all slaves, even
if there is already an active connection for them. This is bad because
at boot slaves first try to autoconnect, then the autoconnect-slaves
of the master kicks in and disconnects/reactivates them.

The only reason why the forceful reactivation was added was to fix
[1]; in that scenario, a slave connection is already active as
non-slave; then it is updated to be a slave; later, the master with
autoconnect-slaves is manually activated. NetworkManager should detect
that the slave connection must now be activated by autoconnect-slaves.

Add a specific check for such situation, instead of always
reactivating all slaves.

[1] https://bugzilla.redhat.com/show_bug.cgi?id=1845018

Fixes: 4985ca5ada9b ('manager: allow autoconnect-slaves to reconnect the same connection')
(cherry picked from commit 024e983c8e38d1f325ac64b9d84b2332afcd6549)
(cherry picked from commit d07d515dd74aeff7149248a2d348fa72ccc47bb4)
(cherry picked from commit 4df63b205e9f54d5f0d0628fac64d0bcb4f6c3fd)

1 files changed, 32 insertions, 3 deletions

diff --git a/src/nm-manager.c b/src/nm-manager.c
index 96ca4e2abe..7402aa90f6 100644
--- a/src/nm-manager.c
+++ b/src/nm-manager.c
@@ -4926,6 +4926,27 @@ _new_active_connection (NMManager *self,
 	                                                  device);
 }
 
+static gboolean
+active_connection_master_changed (NMActiveConnection *ac)
+{
+	NMConnection *applied, *connection;
+	NMSettingsConnection *settings;
+	NMSettingConnection *s_con1, *s_con2;
+
+	applied = nm_active_connection_get_applied_connection (ac);
+	settings = nm_active_connection_get_settings_connection (ac);
+	connection = nm_settings_connection_get_connection (settings);
+
+	if (applied == connection)
+		return FALSE;
+
+	s_con1 = nm_connection_get_setting_connection (applied);
+	s_con2 = nm_connection_get_setting_connection (connection);
+
+	return !nm_streq0 (nm_setting_connection_get_master (s_con1),
+	                   nm_setting_connection_get_master (s_con2));
+}
+
 static void
 _internal_activation_auth_done (NMManager *self,
                                 NMActiveConnection *active,
@@ -4935,6 +4956,7 @@ _internal_activation_auth_done (NMManager *self,
 	NMManagerPrivate *priv = NM_MANAGER_GET_PRIVATE (self);
 	NMActiveConnection *ac;
 	gs_free_error GError *error = NULL;
+	NMActivationReason reason;
 
 	nm_assert (NM_IS_ACTIVE_CONNECTION (active));
 
@@ -4946,13 +4968,20 @@ _internal_activation_auth_done (NMManager *self,
 	 * We also check this earlier, but there we may fail to detect a duplicate
 	 * if the existing active connection was undergoing authorization.
 	 */
-	if (NM_IN_SET (nm_active_connection_get_activation_reason (active), NM_ACTIVATION_REASON_EXTERNAL,
-	                                                                    NM_ACTIVATION_REASON_ASSUME,
-	                                                                    NM_ACTIVATION_REASON_AUTOCONNECT)) {
+	reason = nm_active_connection_get_activation_reason (active);
+	if (NM_IN_SET (reason, NM_ACTIVATION_REASON_EXTERNAL,
+	                       NM_ACTIVATION_REASON_ASSUME,
+	                       NM_ACTIVATION_REASON_AUTOCONNECT,
+	                       NM_ACTIVATION_REASON_AUTOCONNECT_SLAVES)) {
 		c_list_for_each_entry (ac, &priv->active_connections_lst_head, active_connections_lst) {
 			if (   nm_active_connection_get_device (ac) == nm_active_connection_get_device (active)
 			    && nm_active_connection_get_settings_connection (ac) == nm_active_connection_get_settings_connection (active)
 			    && nm_active_connection_get_state (ac) <= NM_ACTIVE_CONNECTION_STATE_ACTIVATED) {
+
+				if (   reason == NM_ACTIVATION_REASON_AUTOCONNECT_SLAVES
+				    && active_connection_master_changed (ac))
+					break;
+
 				g_set_error (&error,
 				             NM_MANAGER_ERROR,
 				             NM_MANAGER_ERROR_CONNECTION_ALREADY_ACTIVE,