* [PATCH] ip_tunnel: the lack of vti_link_ops' dellink() cause kernel panic
@ 2014-11-23 7:04 Xin Long
2014-11-24 14:18 ` Nicolas Dichtel
0 siblings, 1 reply; 4+ messages in thread
From: Xin Long @ 2014-11-23 7:04 UTC (permalink / raw)
To: network dev, Steffen Klassert; +Cc: Xin Long, Cong Wang
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>
---
net/ipv4/ip_vti.c | 1 +
net/ipv6/ip6_vti.c | 11 +++++++++++
2 files changed, 12 insertions(+)
diff --git a/net/ipv4/ip_vti.c b/net/ipv4/ip_vti.c
index 3e86101..1a7e979 100644
--- a/net/ipv4/ip_vti.c
+++ b/net/ipv4/ip_vti.c
@@ -528,6 +528,7 @@ static struct rtnl_link_ops vti_link_ops __read_mostly = {
.validate = vti_tunnel_validate,
.newlink = vti_newlink,
.changelink = vti_changelink,
+ .dellink = ip_tunnel_dellink,
.get_size = vti_get_size,
.fill_info = vti_fill_info,
};
diff --git a/net/ipv6/ip6_vti.c b/net/ipv6/ip6_vti.c
index 31089d1..bcda14d 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)
--
1.8.3.1
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH] ip_tunnel: the lack of vti_link_ops' dellink() cause kernel panic
2014-11-23 7:04 [PATCH] ip_tunnel: the lack of vti_link_ops' dellink() cause kernel panic Xin Long
@ 2014-11-24 14:18 ` Nicolas Dichtel
2014-11-25 5:53 ` lucien xin
0 siblings, 1 reply; 4+ messages in thread
From: Nicolas Dichtel @ 2014-11-24 14:18 UTC (permalink / raw)
To: Xin Long, network dev, Steffen Klassert; +Cc: Cong Wang
Le 23/11/2014 08:04, Xin Long a écrit :
> 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>
> ---
> net/ipv4/ip_vti.c | 1 +
> net/ipv6/ip6_vti.c | 11 +++++++++++
> 2 files changed, 12 insertions(+)
>
> diff --git a/net/ipv4/ip_vti.c b/net/ipv4/ip_vti.c
> index 3e86101..1a7e979 100644
> --- a/net/ipv4/ip_vti.c
> +++ b/net/ipv4/ip_vti.c
> @@ -528,6 +528,7 @@ static struct rtnl_link_ops vti_link_ops __read_mostly = {
> .validate = vti_tunnel_validate,
> .newlink = vti_newlink,
> .changelink = vti_changelink,
> + .dellink = ip_tunnel_dellink,
Nitpicking: please, use a tab instead of space to align the '=', like other
lines.
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] ip_tunnel: the lack of vti_link_ops' dellink() cause kernel panic
2014-11-24 14:18 ` Nicolas Dichtel
@ 2014-11-25 5:53 ` lucien xin
2014-11-25 6:08 ` David Miller
0 siblings, 1 reply; 4+ messages in thread
From: lucien xin @ 2014-11-25 5:53 UTC (permalink / raw)
To: Nicolas Dichtel; +Cc: network dev, Steffen Klassert, Cong Wang
>
> Nitpicking: please, use a tab instead of space to align the '=', like other
> lines.
ok, I will repost it.
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] ip_tunnel: the lack of vti_link_ops' dellink() cause kernel panic
2014-11-25 5:53 ` lucien xin
@ 2014-11-25 6:08 ` David Miller
0 siblings, 0 replies; 4+ messages in thread
From: David Miller @ 2014-11-25 6:08 UTC (permalink / raw)
To: lucien.xin; +Cc: nicolas.dichtel, netdev, steffen.klassert, cwang
From: lucien xin <lucien.xin@gmail.com>
Date: Tue, 25 Nov 2014 13:53:15 +0800
>> Nitpicking: please, use a tab instead of space to align the '=', like other
>> lines.
>
> ok, I will repost it.
That's pointless, as I already applied your original patch to
my tree.
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2014-11-25 6:08 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2014-11-23 7:04 [PATCH] ip_tunnel: the lack of vti_link_ops' dellink() cause kernel panic Xin Long
2014-11-24 14:18 ` Nicolas Dichtel
2014-11-25 5:53 ` lucien xin
2014-11-25 6:08 ` David Miller
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).