openvswitch: retain parsed IPv6 header fields in flow on error skipping extension headers
When an error occurs skipping IPv6 extension headers retain the already
parsed IP protocol and IPv6 addresses in the flow. Also assume that the
packet is not a fragment in the absence of information to the contrary;
that is always use the frag_off value set by ipv6_skip_exthdr().
This allows matching on the IP protocol and IPv6 addresses of packets
with malformed extension headers.
Signed-off-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/openvswitch/flow.c b/net/openvswitch/flow.c
index 9760dc4..9db8733 100644
--- a/net/openvswitch/flow.c
+++ b/net/openvswitch/flow.c
@@ -272,8 +272,6 @@
key->ipv6.addr.dst = nh->daddr;
payload_ofs = ipv6_skip_exthdr(skb, payload_ofs, &nexthdr, &frag_off);
- if (unlikely(payload_ofs < 0))
- return -EINVAL;
if (frag_off) {
if (frag_off & htons(~0x7))
@@ -284,6 +282,13 @@
key->ip.frag = OVS_FRAG_TYPE_NONE;
}
+ /* Delayed handling of error in ipv6_skip_exthdr() as it
+ * always sets frag_off to a valid value which may be
+ * used to set key->ip.frag above.
+ */
+ if (unlikely(payload_ofs < 0))
+ return -EPROTO;
+
nh_len = payload_ofs - nh_ofs;
skb_set_transport_header(skb, nh_ofs + nh_len);
key->ip.proto = nexthdr;
@@ -623,12 +628,16 @@
nh_len = parse_ipv6hdr(skb, key);
if (unlikely(nh_len < 0)) {
- memset(&key->ip, 0, sizeof(key->ip));
- memset(&key->ipv6.addr, 0, sizeof(key->ipv6.addr));
- if (nh_len == -EINVAL) {
+ switch (nh_len) {
+ case -EINVAL:
+ memset(&key->ip, 0, sizeof(key->ip));
+ memset(&key->ipv6.addr, 0, sizeof(key->ipv6.addr));
+ /* fall-through */
+ case -EPROTO:
skb->transport_header = skb->network_header;
error = 0;
- } else {
+ break;
+ default:
error = nh_len;
}
return error;