openvswitch: take into account de-fragmentation/gso_size in execute_check_pkt_len

ovs connection tracking module performs de-fragmentation on incoming
fragmented traffic. Take info account if traffic has been de-fragmented
in execute_check_pkt_len action otherwise we will perform the wrong
nested action considering the original packet size. This issue typically
occurs if ovs-vswitchd adds a rule in the pipeline that requires connection
tracking (e.g. OVN stateful ACLs) before execute_check_pkt_len action.
Moreover take into account GSO fragment size for GSO packet in
execute_check_pkt_len routine

Fixes: 4d5ec89fc8 ("net: openvswitch: Add a new action check_pkt_len")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Lorenzo Bianconi 2020-06-23 18:33:15 +02:00 committed by David S. Miller
parent 0275875530
commit 1784365570

View File

@ -1169,9 +1169,10 @@ static int execute_check_pkt_len(struct datapath *dp, struct sk_buff *skb,
struct sw_flow_key *key,
const struct nlattr *attr, bool last)
{
struct ovs_skb_cb *ovs_cb = OVS_CB(skb);
const struct nlattr *actions, *cpl_arg;
int len, max_len, rem = nla_len(attr);
const struct check_pkt_len_arg *arg;
int rem = nla_len(attr);
bool clone_flow_key;
/* The first netlink attribute in 'attr' is always
@ -1180,7 +1181,11 @@ static int execute_check_pkt_len(struct datapath *dp, struct sk_buff *skb,
cpl_arg = nla_data(attr);
arg = nla_data(cpl_arg);
if (skb->len <= arg->pkt_len) {
len = ovs_cb->mru ? ovs_cb->mru + skb->mac_len : skb->len;
max_len = arg->pkt_len;
if ((skb_is_gso(skb) && skb_gso_validate_mac_len(skb, max_len)) ||
len <= max_len) {
/* Second netlink attribute in 'attr' is always
* 'OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_LESS_EQUAL'.
*/