Message ID | 1520387817-11137-1-git-send-email-u9012063@gmail.com |
---|---|
State | Changes Requested, archived |
Delegated to: | David Miller |
Headers | show |
Series | [net-next] openvswitch: fix vport packet length check. | expand |
On Tue, Mar 6, 2018 at 5:56 PM, William Tu <u9012063@gmail.com> wrote: > 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 <u9012063@gmail.com> > --- > net/openvswitch/vport.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/net/openvswitch/vport.c b/net/openvswitch/vport.c > index b6c8524032a0..7718d5b4cf8a 100644 > --- a/net/openvswitch/vport.c > +++ b/net/openvswitch/vport.c > @@ -467,7 +467,7 @@ int ovs_vport_receive(struct vport *vport, struct sk_buff *skb, > static unsigned int packet_length(const struct sk_buff *skb, > struct net_device *dev) Can you also change return type of this function? > { > - 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) > -- > 2.7.4 >
On Wed, Mar 7, 2018 at 1:18 PM, Pravin Shelar <pshelar@ovn.org> wrote: > On Tue, Mar 6, 2018 at 5:56 PM, William Tu <u9012063@gmail.com> wrote: >> 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 <u9012063@gmail.com> >> --- >> net/openvswitch/vport.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/net/openvswitch/vport.c b/net/openvswitch/vport.c >> index b6c8524032a0..7718d5b4cf8a 100644 >> --- a/net/openvswitch/vport.c >> +++ b/net/openvswitch/vport.c >> @@ -467,7 +467,7 @@ int ovs_vport_receive(struct vport *vport, struct sk_buff *skb, >> static unsigned int packet_length(const struct sk_buff *skb, >> struct net_device *dev) > Can you also change return type of this function? > OK, I will change to int. Thanks
diff --git a/net/openvswitch/vport.c b/net/openvswitch/vport.c index b6c8524032a0..7718d5b4cf8a 100644 --- a/net/openvswitch/vport.c +++ b/net/openvswitch/vport.c @@ -467,7 +467,7 @@ int ovs_vport_receive(struct vport *vport, struct sk_buff *skb, static unsigned 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)
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 <u9012063@gmail.com> --- net/openvswitch/vport.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)