| Message ID | 0324dc4a3a7740e4766e16539f4ed41b356f991d.1372764542.git.yamahata@valinux.co.jp |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
From: Isaku Yamahata <yamahata@valinux.co.jp> Date: Tue, 2 Jul 2013 20:30:10 +0900 > The dev_forward_skb() assignment of pkt_type should be done > after the call to eth_type_trans(). > > ip-encapsulated packets can be handled by localhost. But skb->pkt_type > can be PACKET_OTHERHOST when packet comes via veth into ip tunnel device. > In that case, the packet is dropped by ip_rcv(). > Although this example uses gretap. l2tp-eth also has same issue. > For l2tp-eth case, add dummy device for ip address and ip l2tp command. ... > Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp> Applied, but I had to adjust the patch because in net-next we use a new helper function (skb_scrub_packet()) to clear things out from dev_forward_skb(). -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Le 03/07/2013 01:00, David Miller a écrit : > From: Isaku Yamahata <yamahata@valinux.co.jp> > Date: Tue, 2 Jul 2013 20:30:10 +0900 > >> The dev_forward_skb() assignment of pkt_type should be done >> after the call to eth_type_trans(). >> >> ip-encapsulated packets can be handled by localhost. But skb->pkt_type >> can be PACKET_OTHERHOST when packet comes via veth into ip tunnel device. >> In that case, the packet is dropped by ip_rcv(). >> Although this example uses gretap. l2tp-eth also has same issue. >> For l2tp-eth case, add dummy device for ip address and ip l2tp command. > ... >> Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp> > > Applied, but I had to adjust the patch because in net-next we use > a new helper function (skb_scrub_packet()) to clear things out from > dev_forward_skb(). What about calling skb_scrub_packet() after eth_type_trans()? I wonder if the same problem may happen the day gre will support x-netns, because skb_scrub_packet() is also called before eth_type_trans() in ip_tunnel_rcv(). -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
From: Nicolas Dichtel <nicolas.dichtel@6wind.com> Date: Wed, 03 Jul 2013 16:53:52 +0200 > Le 03/07/2013 01:00, David Miller a écrit : >> From: Isaku Yamahata <yamahata@valinux.co.jp> >> Date: Tue, 2 Jul 2013 20:30:10 +0900 >> >>> The dev_forward_skb() assignment of pkt_type should be done >>> after the call to eth_type_trans(). >>> >>> ip-encapsulated packets can be handled by localhost. But skb->pkt_type >>> can be PACKET_OTHERHOST when packet comes via veth into ip tunnel >>> device. >>> In that case, the packet is dropped by ip_rcv(). >>> Although this example uses gretap. l2tp-eth also has same issue. >>> For l2tp-eth case, add dummy device for ip address and ip l2tp >>> command. >> ... >>> Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp> >> >> Applied, but I had to adjust the patch because in net-next we use >> a new helper function (skb_scrub_packet()) to clear things out from >> dev_forward_skb(). > What about calling skb_scrub_packet() after eth_type_trans()? > > I wonder if the same problem may happen the day gre will support > x-netns, > because skb_scrub_packet() is also called before eth_type_trans() in > ip_tunnel_rcv(). That's a fine suggestion, I was just being overly conservative in my forward-porting of his patch. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Le 04/07/2013 23:57, David Miller a écrit : > From: Nicolas Dichtel <nicolas.dichtel@6wind.com> > Date: Wed, 03 Jul 2013 16:53:52 +0200 > >> Le 03/07/2013 01:00, David Miller a écrit : >>> From: Isaku Yamahata <yamahata@valinux.co.jp> >>> Date: Tue, 2 Jul 2013 20:30:10 +0900 >>> >>>> The dev_forward_skb() assignment of pkt_type should be done >>>> after the call to eth_type_trans(). >>>> >>>> ip-encapsulated packets can be handled by localhost. But skb->pkt_type >>>> can be PACKET_OTHERHOST when packet comes via veth into ip tunnel >>>> device. >>>> In that case, the packet is dropped by ip_rcv(). >>>> Although this example uses gretap. l2tp-eth also has same issue. >>>> For l2tp-eth case, add dummy device for ip address and ip l2tp >>>> command. >>> ... >>>> Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp> >>> >>> Applied, but I had to adjust the patch because in net-next we use >>> a new helper function (skb_scrub_packet()) to clear things out from >>> dev_forward_skb(). >> What about calling skb_scrub_packet() after eth_type_trans()? >> >> I wonder if the same problem may happen the day gre will support >> x-netns, >> because skb_scrub_packet() is also called before eth_type_trans() in >> ip_tunnel_rcv(). > > That's a fine suggestion, I was just being overly conservative in my > forward-porting of his patch. > Ok, I will wait that net-next opens to submit this patch. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/core/dev.c b/net/core/dev.c index 722f633..b179b8a 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -1662,8 +1662,12 @@ int dev_forward_skb(struct net_device *dev, struct sk_buff *skb) skb->skb_iif = 0; skb_dst_drop(skb); skb->tstamp.tv64 = 0; - skb->pkt_type = PACKET_HOST; skb->protocol = eth_type_trans(skb, dev); + /* + * eth_type_trans() can set pkt_type. + * clear pkt_type _after_ calling eth_type_trans() + */ + skb->pkt_type = PACKET_HOST; skb->mark = 0; secpath_reset(skb); nf_reset(skb);
The dev_forward_skb() assignment of pkt_type should be done after the call to eth_type_trans(). ip-encapsulated packets can be handled by localhost. But skb->pkt_type can be PACKET_OTHERHOST when packet comes via veth into ip tunnel device. In that case, the packet is dropped by ip_rcv(). Although this example uses gretap. l2tp-eth also has same issue. For l2tp-eth case, add dummy device for ip address and ip l2tp command. netns A | root netns | netns B veth<->veth=bridge=gretap <-loop back-> gretap=bridge=veth<->veth arp packet -> pkt_type BROADCAST------------>ip_rcv()------------------------> <- arp reply pkt_type ip_rcv()<-----------------OTHERHOST drop sample operations ip link add tapa type gretap remote 172.17.107.4 local 172.17.107.3 ip link add tapb type gretap remote 172.17.107.3 local 172.17.107.4 ip link set tapa up ip link set tapb up ip address add 172.17.107.3 dev tapa ip address add 172.17.107.4 dev tapb ip route get 172.17.107.3 > local 172.17.107.3 dev lo src 172.17.107.3 > cache <local> ip route get 172.17.107.4 > local 172.17.107.4 dev lo src 172.17.107.4 > cache <local> ip link add vetha type veth peer name vetha-peer ip link add vethb type veth peer name vethb-peer brctl addbr bra brctl addbr brb brctl addif bra tapa brctl addif bra vetha-peer brctl addif brb tapb brctl addif brb vethb-peer brctl show > bridge name bridge id STP enabled interfaces > bra 8000.6ea21e758ff1 no tapa > vetha-peer > brb 8000.420020eb92d5 no tapb > vethb-peer ip link set vetha-peer up ip link set vethb-peer up ip link set bra up ip link set brb up ip netns add a ip netns add b ip link set vetha netns a ip link set vethb netns b ip netns exec a ip address add 10.0.0.3/24 dev vetha ip netns exec b ip address add 10.0.0.4/24 dev vethb ip netns exec a ip link set vetha up ip netns exec b ip link set vethb up ip netns exec a arping -I vetha 10.0.0.4 ARPING 10.0.0.4 from 10.0.0.3 vetha ^CSent 2 probes (2 broadcast(s)) Received 0 response(s) Cc: Jason Wang <jasowang@redhat.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Patrick McHardy <kaber@trash.net> Cc: Hong Zhiguo <honkiko@gmail.com> Cc: Rami Rosen <ramirose@gmail.com> Cc: Tom Parkin <tparkin@katalix.com> Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: Pravin B Shelar <pshelar@nicira.com> Cc: Jesse Gross <jesse@nicira.com> Cc: dev@openvswitch.org Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp> --- net/core/dev.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)