2012-08-30 02:19:54

by Alan Ott

Subject: [PATCH] 6lowpan: Make a copy of skb's delivered to 6lowpan

Since lowpan_process_data() modifies the skb (by calling skb_pull()), we
need our own copy so that it doesn't affect the data received by other
protcols (in this case, af_ieee802154).

Signed-off-by: Alan Ott <[email protected]>
---
net/ieee802154/6lowpan.c | 9 ++++++++-
1 files changed, 8 insertions(+), 1 deletions(-)

diff --git a/net/ieee802154/6lowpan.c b/net/ieee802154/6lowpan.c
index 6a09522..ce33b02 100644
--- a/net/ieee802154/6lowpan.c
+++ b/net/ieee802154/6lowpan.c
@@ -1133,6 +1133,8 @@ static int lowpan_validate(struct nlattr *tb[], struct nlattr *data[])
static int lowpan_rcv(struct sk_buff *skb, struct net_device *dev,
struct packet_type *pt, struct net_device *orig_dev)
{
+ struct sk_buff *local_skb;
+
if (!netif_running(dev))
goto drop;

@@ -1144,7 +1146,12 @@ static int lowpan_rcv(struct sk_buff *skb, struct net_device *dev,
case LOWPAN_DISPATCH_IPHC: /* ipv6 datagram */
case LOWPAN_DISPATCH_FRAG1: /* first fragment header */
case LOWPAN_DISPATCH_FRAGN: /* next fragments headers */
- lowpan_process_data(skb);
+ local_skb = skb_copy(skb, GFP_ATOMIC);
+ if (!local_skb)
+ goto drop;
+ lowpan_process_data(local_skb);
+
+ kfree_skb(skb);
break;
default:
break;
--
1.7.0.4

2012-08-30 02:19:56

by Alan Ott

Subject: [PATCH 2/2] 6lowpan: handle NETDEV_UNREGISTER event

Before, it was impossible to remove a wpan device which had lowpan
attached to it.

Signed-off-by: Alan Ott <[email protected]>
---
net/ieee802154/6lowpan.c | 44 +++++++++++++++++++++++++++++++++++++-------
1 files changed, 37 insertions(+), 7 deletions(-)

diff --git a/net/ieee802154/6lowpan.c b/net/ieee802154/6lowpan.c
index ce33b02..fb41e08 100644
--- a/net/ieee802154/6lowpan.c
+++ b/net/ieee802154/6lowpan.c
@@ -1063,12 +1063,6 @@ out:
return (err < 0 ? NETDEV_TX_BUSY : NETDEV_TX_OK);
}

-static void lowpan_dev_free(struct net_device *dev)
-{
- dev_put(lowpan_dev_info(dev)->real_dev);
- free_netdev(dev);
-}
-
static struct wpan_phy *lowpan_get_phy(const struct net_device *dev)
{
struct net_device *real_dev = lowpan_dev_info(dev)->real_dev;
@@ -1118,7 +1112,7 @@ static void lowpan_setup(struct net_device *dev)
dev->netdev_ops = &lowpan_netdev_ops;
dev->header_ops = &lowpan_header_ops;
dev->ml_priv = &lowpan_mlme;
- dev->destructor = lowpan_dev_free;
+ dev->destructor = free_netdev;
}

static int lowpan_validate(struct nlattr *tb[], struct nlattr *data[])
@@ -1244,6 +1238,34 @@ static inline void __init lowpan_netlink_fini(void)
rtnl_link_unregister(&lowpan_link_ops);
}

+static int lowpan_device_event(struct notifier_block *unused,
+ unsigned long event,
+ void *ptr)
+{
+ struct net_device *dev = ptr;
+ LIST_HEAD(del_list);
+ struct lowpan_dev_record *entry, *tmp;
+
+ if (dev->type != ARPHRD_IEEE802154)
+ goto out;
+
+ if (event == NETDEV_UNREGISTER) {
+ list_for_each_entry_safe(entry, tmp, &lowpan_devices, list) {
+ if (lowpan_dev_info(entry->ldev)->real_dev == dev)
+ lowpan_dellink(entry->ldev, &del_list);
+ }
+
+ unregister_netdevice_many(&del_list);
+ };
+
+out:
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block lowpan_dev_notifier = {
+ .notifier_call = lowpan_device_event,
+};
+
static struct packet_type lowpan_packet_type = {
.type = __constant_htons(ETH_P_IEEE802154),
.func = lowpan_rcv,
@@ -1258,6 +1280,12 @@ static int __init lowpan_init_module(void)
goto out;

dev_add_pack(&lowpan_packet_type);
+
+ err = register_netdevice_notifier(&lowpan_dev_notifier);
+ if (err < 0) {
+ dev_remove_pack(&lowpan_packet_type);
+ lowpan_netlink_fini();
+ }
out:
return err;
}
@@ -1270,6 +1298,8 @@ static void __exit lowpan_cleanup_module(void)

dev_remove_pack(&lowpan_packet_type);

+ unregister_netdevice_notifier(&lowpan_dev_notifier);
+
/* Now 6lowpan packet_type is removed, so no new fragments are
* expected on RX, therefore that's the time to clean incomplete
* fragments.
--
1.7.0.4