Properly respect other configured MTUs for other vlans. Properly respect parent of vlan MTU if configured. Also avoid errors when possible. This helps VLANs MTU handling but all the other interfaces as gre/gif/... needs the same handling. It is better to require reboot on MTU changes especially on complex configurations.

1 files changed, 14 insertions, 9 deletions

diff --git a/etc/inc/interfaces.inc b/etc/inc/interfaces.inc
index cabf8a2..e9b8f6e 100644
--- a/etc/inc/interfaces.inc
+++ b/etc/inc/interfaces.inc
@@ -2829,7 +2829,7 @@ function interface_vlan_adapt_mtu($vlanifs, $mtu) {
 		$assignedport = convert_real_interface_to_friendly_interface_name($vlan['vlanif']);
 		if (!empty($assignedport)) {
 			if (!empty($config['interfaces'][$assignedport]['mtu'])) {
-				pfSense_interface_mtu($vlan['vlanif'], $mtu);
+				pfSense_interface_mtu($vlan['vlanif'], $config['interfaces'][$assignedport]['mtu']);
 			} else {
 				if (get_interface_mtu($vlan['vlanif']) != $mtu)
 					pfSense_interface_mtu($vlan['vlanif'], $mtu);
@@ -2996,18 +2996,20 @@ function interface_configure($interface = "wan", $reloadall = false, $linkupeven
 	if (!empty($wancfg['mtu'])) {
 		if (stristr($realif, "_vlan")) {
 			$assignedparent = convert_real_interface_to_friendly_interface_name($realhwif);
-			if (!empty($assignedparent) && !empty($config['interfaces'][$assignedparent]['mtu']))
+			if (!empty($assignedparent) && !empty($config['interfaces'][$assignedparent]['mtu'])) {
 				$parentmtu = $config['interfaces'][$assignedparent]['mtu'];
-			else {
+				if ($wancfg['mtu'] > $parentmtu)
+					log_error("There is a conflict on MTU between parent {$realhwif} and VLAN({$realif})");
+			} else
 				$parentmtu = get_interface_mtu($realhwif);
-				$parentmtu = interface_vlan_mtu_configured($realhwif, $parentmtu, $realif);
-			}
 
-			if (get_interface_mtu($realhwif) != $wancfg['mtu'])
-				pfSense_interface_mtu($realhwif, $wancfg['mtu']);
+			$parentmtu = interface_vlan_mtu_configured($realhwif, $parentmtu);
+
+			if (get_interface_mtu($realhwif) != $parentmtu)
+				pfSense_interface_mtu($realhwif, $parentmtu);
 
 			/* All vlans need to use the same mtu value as their parent. */
-			interface_vlan_adapt_mtu(link_interface_to_vlans($realhwif), $wancfg['mtu']);
+			interface_vlan_adapt_mtu(link_interface_to_vlans($realhwif), $parentmtu);
 		} else if (substr($realif, 0, 4) == 'lagg') {
 			/* LAGG interface must be destroyed and re-created to change MTU */
 			if ($wancfg['mtu'] != get_interface_mtu($realif)) {
@@ -3025,7 +3027,10 @@ function interface_configure($interface = "wan", $reloadall = false, $linkupeven
 				pfSense_interface_mtu($realif, $wancfg['mtu']);
 
 			/* This case is needed when the parent of vlans is being configured */
-			interface_vlan_adapt_mtu(link_interface_to_vlans($realif), $wancfg['mtu']);
+			$vlans = link_interface_to_vlans($realif);
+			if (is_array($vlans))
+				interface_vlan_adapt_mtu($vlans, $wancfg['mtu']);
+			unset($vlans);
 		}
 		/* XXX: What about gre/gif/.. ? */
 	}