flow_dissector: For stripped vlan, get vlan info from skb->vlan_tci

Early in the datapath skb_vlan_untag function is called, stripped
the vlan from the skb and set skb->vlan_tci and skb->vlan_proto fields.

The current dissection doesn't handle stripped vlan packets correctly.
In some flows, vlan doesn't exist in skb->data anymore when applying
flow dissection on the skb, fix that.

In case vlan info wasn't stripped before applying flow_dissector (RPS
flow for example), or in case of skb with multiple vlans (e.g. 802.1ad),
get the vlan info from skb->data. The flow_dissector correctly skips
any number of vlans and stores only the first level vlan.

Fixes: 0744dd00c1 ('net: introduce skb_flow_dissect()')
Signed-off-by: Hadar Hen Zion <hadarh@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Hadar Hen Zion 2016-08-17 13:36:10 +03:00 committed by David S. Miller
parent 92bcdcc672
commit d5709f7ab7
1 changed files with 26 additions and 8 deletions

View File

@ -119,12 +119,14 @@ bool __skb_flow_dissect(const struct sk_buff *skb,
struct flow_dissector_key_ports *key_ports;
struct flow_dissector_key_tags *key_tags;
struct flow_dissector_key_keyid *key_keyid;
bool skip_vlan = false;
u8 ip_proto = 0;
bool ret = false;
if (!data) {
data = skb->data;
proto = skb->protocol;
proto = skb_vlan_tag_present(skb) ?
skb->vlan_proto : skb->protocol;
nhoff = skb_network_offset(skb);
hlen = skb_headlen(skb);
}
@ -243,23 +245,39 @@ bool __skb_flow_dissect(const struct sk_buff *skb,
case htons(ETH_P_8021AD):
case htons(ETH_P_8021Q): {
const struct vlan_hdr *vlan;
struct vlan_hdr _vlan;
vlan = __skb_header_pointer(skb, nhoff, sizeof(_vlan), data, hlen, &_vlan);
if (!vlan)
goto out_bad;
if (skb_vlan_tag_present(skb))
proto = skb->protocol;
if (!skb_vlan_tag_present(skb) ||
proto == cpu_to_be16(ETH_P_8021Q) ||
proto == cpu_to_be16(ETH_P_8021AD)) {
struct vlan_hdr _vlan;
vlan = __skb_header_pointer(skb, nhoff, sizeof(_vlan),
data, hlen, &_vlan);
if (!vlan)
goto out_bad;
proto = vlan->h_vlan_encapsulated_proto;
nhoff += sizeof(*vlan);
if (skip_vlan)
goto again;
}
skip_vlan = true;
if (dissector_uses_key(flow_dissector,
FLOW_DISSECTOR_KEY_VLANID)) {
key_tags = skb_flow_dissector_target(flow_dissector,
FLOW_DISSECTOR_KEY_VLANID,
target_container);
key_tags->vlan_id = skb_vlan_tag_get_id(skb);
if (skb_vlan_tag_present(skb))
key_tags->vlan_id = skb_vlan_tag_get_id(skb);
else
key_tags->vlan_id = ntohs(vlan->h_vlan_TCI) &
VLAN_VID_MASK;
}
proto = vlan->h_vlan_encapsulated_proto;
nhoff += sizeof(*vlan);
goto again;
}
case htons(ETH_P_PPP_SES): {