make vlans inherit their parents hardmtu as well as mtu.

from brad@ and tested locally.

diff --git a/sys/net/if_vlan.c b/sys/net/if_vlan.c
index 218fe2b..cc4691e 100644 (file)
--- a/sys/net/if_vlan.c
+++ b/sys/net/if_vlan.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: if_vlan.c,v 1.124 2015/05/23 08:32:12 mpi Exp $       */
+/*     $OpenBSD: if_vlan.c,v 1.125 2015/05/26 03:01:54 dlg Exp $       */
 
 /*
  * Copyright 1998 Massachusetts Institute of Technology
@@ -394,10 +394,13 @@ vlan_config(struct ifvlan *ifv, struct ifnet *p, u_int16_t tag)
        ifv->ifv_p = p;
        ifv->ifv_if.if_baudrate = p->if_baudrate;
 
-       if (p->if_capabilities & IFCAP_VLAN_MTU)
+       if (p->if_capabilities & IFCAP_VLAN_MTU) {
                ifv->ifv_if.if_mtu = p->if_mtu;
-       else
+               ifv->ifv_if.if_hardmtu = p->if_hardmtu;
+       } else {
                ifv->ifv_if.if_mtu = p->if_mtu - EVL_ENCAPLEN;
+               ifv->ifv_if.if_hardmtu = p->if_hardmtu - EVL_ENCAPLEN;
+       }
 
        ifv->ifv_if.if_flags = p->if_flags &
            (IFF_UP | IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST);
@@ -510,6 +513,7 @@ vlan_unconfig(struct ifnet *ifp, struct ifnet *newp)
        /* Disconnect from parent. */
        ifv->ifv_p = NULL;
        ifv->ifv_if.if_mtu = ETHERMTU;
+       ifv->ifv_if.if_hardmtu = ETHERMTU;
        ifv->ifv_flags = 0;
 
        /* Clear our MAC address. */
@@ -562,7 +566,7 @@ vlan_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
        struct ifreq    *ifr;
        struct ifvlan   *ifv;
        struct vlanreq   vlr;
-       int              error = 0, p_mtu = 0, s;
+       int              error = 0, s;
 
        ifr = (struct ifreq *)data;
        ifa = (struct ifaddr *)data;
@@ -590,12 +594,8 @@ vlan_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
 
        case SIOCSIFMTU:
                if (ifv->ifv_p != NULL) {
-                       if (ifv->ifv_p->if_capabilities & IFCAP_VLAN_MTU)
-                               p_mtu = ifv->ifv_p->if_hardmtu;
-                       else
-                               p_mtu = ifv->ifv_p->if_hardmtu - EVL_ENCAPLEN;
-                       
-                       if (ifr->ifr_mtu > p_mtu || ifr->ifr_mtu < ETHERMIN)
+                       if (ifr->ifr_mtu < ETHERMIN ||
+                           ifr->ifr_mtu > ifv->ifv_if.if_hardmtu)
                                error = EINVAL;
                        else
                                ifp->if_mtu = ifr->ifr_mtu;