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author | lucien <lucien.xin@gmail.com> | 2014-11-23 15:04:11 +0800 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2014-11-23 21:11:17 -0500 |
commit | 20ea60ca9952bd19d4b0d74719daba305aef5178 (patch) | |
tree | 8c2b69fc5c19d9721d8454337a9f21ea1bdf7075 /net/ipv6/ip6_vti.c | |
parent | 73112f9b08ddb32c5cdaccda61bd88dfe9baf8b2 (diff) | |
download | linux-20ea60ca9952bd19d4b0d74719daba305aef5178.tar.gz linux-20ea60ca9952bd19d4b0d74719daba305aef5178.tar.xz |
ip_tunnel: the lack of vti_link_ops' dellink() cause kernel panic
Now the vti_link_ops do not point the .dellink, for fb tunnel device
(ip_vti0), the net_device will be removed as the default .dellink is
unregister_netdevice_queue,but the tunnel still in the tunnel list,
then if we add a new vti tunnel, in ip_tunnel_find():
hlist_for_each_entry_rcu(t, head, hash_node) {
if (local == t->parms.iph.saddr &&
remote == t->parms.iph.daddr &&
link == t->parms.link &&
==> type == t->dev->type &&
ip_tunnel_key_match(&t->parms, flags, key))
break;
}
the panic will happen, cause dev of ip_tunnel *t is null:
[ 3835.072977] IP: [<ffffffffa04103fd>] ip_tunnel_find+0x9d/0xc0 [ip_tunnel]
[ 3835.073008] PGD b2c21067 PUD b7277067 PMD 0
[ 3835.073008] Oops: 0000 [#1] SMP
.....
[ 3835.073008] Stack:
[ 3835.073008] ffff8800b72d77f0 ffffffffa0411924 ffff8800bb956000 ffff8800b72d78e0
[ 3835.073008] ffff8800b72d78a0 0000000000000000 ffffffffa040d100 ffff8800b72d7858
[ 3835.073008] ffffffffa040b2e3 0000000000000000 0000000000000000 0000000000000000
[ 3835.073008] Call Trace:
[ 3835.073008] [<ffffffffa0411924>] ip_tunnel_newlink+0x64/0x160 [ip_tunnel]
[ 3835.073008] [<ffffffffa040b2e3>] vti_newlink+0x43/0x70 [ip_vti]
[ 3835.073008] [<ffffffff8150d4da>] rtnl_newlink+0x4fa/0x5f0
[ 3835.073008] [<ffffffff812f68bb>] ? nla_strlcpy+0x5b/0x70
[ 3835.073008] [<ffffffff81508fb0>] ? rtnl_link_ops_get+0x40/0x60
[ 3835.073008] [<ffffffff8150d11f>] ? rtnl_newlink+0x13f/0x5f0
[ 3835.073008] [<ffffffff81509cf4>] rtnetlink_rcv_msg+0xa4/0x270
[ 3835.073008] [<ffffffff8126adf5>] ? sock_has_perm+0x75/0x90
[ 3835.073008] [<ffffffff81509c50>] ? rtnetlink_rcv+0x30/0x30
[ 3835.073008] [<ffffffff81529e39>] netlink_rcv_skb+0xa9/0xc0
[ 3835.073008] [<ffffffff81509c48>] rtnetlink_rcv+0x28/0x30
....
modprobe ip_vti
ip link del ip_vti0 type vti
ip link add ip_vti0 type vti
rmmod ip_vti
do that one or more times, kernel will panic.
fix it by assigning ip_tunnel_dellink to vti_link_ops' dellink, in
which we skip the unregister of fb tunnel device. do the same on ip6_vti.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Cong Wang <cwang@twopensource.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv6/ip6_vti.c')
-rw-r--r-- | net/ipv6/ip6_vti.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/net/ipv6/ip6_vti.c b/net/ipv6/ip6_vti.c index 31089d153fd3..bcda14de7f84 100644 --- a/net/ipv6/ip6_vti.c +++ b/net/ipv6/ip6_vti.c @@ -905,6 +905,15 @@ static int vti6_newlink(struct net *src_net, struct net_device *dev, return vti6_tnl_create2(dev); } +static void vti6_dellink(struct net_device *dev, struct list_head *head) +{ + struct net *net = dev_net(dev); + struct vti6_net *ip6n = net_generic(net, vti6_net_id); + + if (dev != ip6n->fb_tnl_dev) + unregister_netdevice_queue(dev, head); +} + static int vti6_changelink(struct net_device *dev, struct nlattr *tb[], struct nlattr *data[]) { @@ -980,6 +989,7 @@ static struct rtnl_link_ops vti6_link_ops __read_mostly = { .setup = vti6_dev_setup, .validate = vti6_validate, .newlink = vti6_newlink, + .dellink = vti6_dellink, .changelink = vti6_changelink, .get_size = vti6_get_size, .fill_info = vti6_fill_info, @@ -1020,6 +1030,7 @@ static int __net_init vti6_init_net(struct net *net) if (!ip6n->fb_tnl_dev) goto err_alloc_dev; dev_net_set(ip6n->fb_tnl_dev, net); + ip6n->fb_tnl_dev->rtnl_link_ops = &vti6_link_ops; err = vti6_fb_tnl_dev_init(ip6n->fb_tnl_dev); if (err < 0) |