Commit 5533995b62d02dbbf930f2e59221c2d5ea05aab7
Committed by
David S. Miller
David S. Miller
1 parent
6a7657f562
Exists in
master
and in
7 other branches
[IPIP]: Allow rebinding the tunnel to another interface
Once created, an IP tunnel can't be bound to another device. (reported as https://bugzilla.redhat.com/show_bug.cgi?id=419671) To reproduce: # create a tunnel: ip tunnel add tunneltest0 mode ipip remote 10.0.0.1 dev eth0 # try to change the bounding device from eth0 to eth1: ip tunnel change tunneltest0 dev eth1 # show the result: ip tunnel show tunneltest0 tunneltest0: ip/ip remote 10.0.0.1 local any dev eth0 ttl inherit Notice the bound device has not changed from eth0 to eth1. This patch fixes it. When changing the binding, it also recalculates the MTU according to the new bound device's MTU. If the change is acceptable, I'll do the same for GRE and SIT tunnels. Signed-off-by: Michal Schmidt <mschmidt@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Showing 1 changed file with 40 additions and 26 deletions Side-by-side Diff
net/ipv4/ipip.c
| ... | ... | @@ -651,6 +651,40 @@ |
| 651 | 651 | return 0; |
| 652 | 652 | } |
| 653 | 653 | |
| 654 | +static void ipip_tunnel_bind_dev(struct net_device *dev) | |
| 655 | +{ | |
| 656 | + struct net_device *tdev = NULL; | |
| 657 | + struct ip_tunnel *tunnel; | |
| 658 | + struct iphdr *iph; | |
| 659 | + | |
| 660 | + tunnel = netdev_priv(dev); | |
| 661 | + iph = &tunnel->parms.iph; | |
| 662 | + | |
| 663 | + if (iph->daddr) { | |
| 664 | + struct flowi fl = { .oif = tunnel->parms.link, | |
| 665 | + .nl_u = { .ip4_u = | |
| 666 | + { .daddr = iph->daddr, | |
| 667 | + .saddr = iph->saddr, | |
| 668 | + .tos = RT_TOS(iph->tos) } }, | |
| 669 | + .proto = IPPROTO_IPIP }; | |
| 670 | + struct rtable *rt; | |
| 671 | + if (!ip_route_output_key(&rt, &fl)) { | |
| 672 | + tdev = rt->u.dst.dev; | |
| 673 | + ip_rt_put(rt); | |
| 674 | + } | |
| 675 | + dev->flags |= IFF_POINTOPOINT; | |
| 676 | + } | |
| 677 | + | |
| 678 | + if (!tdev && tunnel->parms.link) | |
| 679 | + tdev = __dev_get_by_index(&init_net, tunnel->parms.link); | |
| 680 | + | |
| 681 | + if (tdev) { | |
| 682 | + dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr); | |
| 683 | + dev->mtu = tdev->mtu - sizeof(struct iphdr); | |
| 684 | + } | |
| 685 | + dev->iflink = tunnel->parms.link; | |
| 686 | +} | |
| 687 | + | |
| 654 | 688 | static int |
| 655 | 689 | ipip_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd) |
| 656 | 690 | { |
| ... | ... | @@ -723,6 +757,11 @@ |
| 723 | 757 | t->parms.iph.ttl = p.iph.ttl; |
| 724 | 758 | t->parms.iph.tos = p.iph.tos; |
| 725 | 759 | t->parms.iph.frag_off = p.iph.frag_off; |
| 760 | + if (t->parms.link != p.link) { | |
| 761 | + t->parms.link = p.link; | |
| 762 | + ipip_tunnel_bind_dev(dev); | |
| 763 | + netdev_state_change(dev); | |
| 764 | + } | |
| 726 | 765 | } |
| 727 | 766 | if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p))) |
| 728 | 767 | err = -EFAULT; |
| 729 | 768 | |
| 730 | 769 | |
| ... | ... | @@ -791,12 +830,9 @@ |
| 791 | 830 | |
| 792 | 831 | static int ipip_tunnel_init(struct net_device *dev) |
| 793 | 832 | { |
| 794 | - struct net_device *tdev = NULL; | |
| 795 | 833 | struct ip_tunnel *tunnel; |
| 796 | - struct iphdr *iph; | |
| 797 | 834 | |
| 798 | 835 | tunnel = netdev_priv(dev); |
| 799 | - iph = &tunnel->parms.iph; | |
| 800 | 836 | |
| 801 | 837 | tunnel->dev = dev; |
| 802 | 838 | strcpy(tunnel->parms.name, dev->name); |
| ... | ... | @@ -804,29 +840,7 @@ |
| 804 | 840 | memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4); |
| 805 | 841 | memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4); |
| 806 | 842 | |
| 807 | - if (iph->daddr) { | |
| 808 | - struct flowi fl = { .oif = tunnel->parms.link, | |
| 809 | - .nl_u = { .ip4_u = | |
| 810 | - { .daddr = iph->daddr, | |
| 811 | - .saddr = iph->saddr, | |
| 812 | - .tos = RT_TOS(iph->tos) } }, | |
| 813 | - .proto = IPPROTO_IPIP }; | |
| 814 | - struct rtable *rt; | |
| 815 | - if (!ip_route_output_key(&rt, &fl)) { | |
| 816 | - tdev = rt->u.dst.dev; | |
| 817 | - ip_rt_put(rt); | |
| 818 | - } | |
| 819 | - dev->flags |= IFF_POINTOPOINT; | |
| 820 | - } | |
| 821 | - | |
| 822 | - if (!tdev && tunnel->parms.link) | |
| 823 | - tdev = __dev_get_by_index(&init_net, tunnel->parms.link); | |
| 824 | - | |
| 825 | - if (tdev) { | |
| 826 | - dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr); | |
| 827 | - dev->mtu = tdev->mtu - sizeof(struct iphdr); | |
| 828 | - } | |
| 829 | - dev->iflink = tunnel->parms.link; | |
| 843 | + ipip_tunnel_bind_dev(dev); | |
| 830 | 844 | |
| 831 | 845 | return 0; |
| 832 | 846 | } |