From 46e371f0e78a82186a83cbcb4f4b8850417c7dd5 Mon Sep 17 00:00:00 2001 From: William Tu Date: Wed, 7 Mar 2018 15:38:48 -0800 Subject: openvswitch: fix vport packet length check. When sending a packet to a tunnel device, the dev's hard_header_len could be larger than the skb->len in function packet_length(). In the case of ip6gretap/erspan, hard_header_len = LL_MAX_HEADER + t_hlen, which is around 180, and an ARP packet sent to this tunnel has skb->len = 42. This causes the 'unsign int length' to become super large because it is negative value, causing the later ovs_vport_send to drop it due to over-mtu size. The patch fixes it by setting it to 0. Signed-off-by: William Tu Acked-by: Pravin B Shelar Signed-off-by: David S. Miller --- net/openvswitch/vport.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'net/openvswitch/vport.c') diff --git a/net/openvswitch/vport.c b/net/openvswitch/vport.c index b6c8524032a0..f81c1d0ddff4 100644 --- a/net/openvswitch/vport.c +++ b/net/openvswitch/vport.c @@ -464,10 +464,10 @@ int ovs_vport_receive(struct vport *vport, struct sk_buff *skb, return 0; } -static unsigned int packet_length(const struct sk_buff *skb, - struct net_device *dev) +static int packet_length(const struct sk_buff *skb, + struct net_device *dev) { - unsigned int length = skb->len - dev->hard_header_len; + int length = skb->len - dev->hard_header_len; if (!skb_vlan_tag_present(skb) && eth_type_vlan(skb->protocol)) @@ -478,7 +478,7 @@ static unsigned int packet_length(const struct sk_buff *skb, * account for 802.1ad. e.g. is_skb_forwardable(). */ - return length; + return length > 0 ? length : 0; } void ovs_vport_send(struct vport *vport, struct sk_buff *skb, u8 mac_proto) -- cgit v1.2.3