mcast packets get looped back to the local machine.
Such packets have a 0-length mac header, we should treat
this like "mac header not set" and abort rule evaluation.
As-is, we just copy data from the network header instead.
Fixes:
96518518cc41 ("netfilter: add nftables")
Reported-by: Blažej Krajňák <krajnak@levonet.sk>
Signed-off-by: Florian Westphal <fw@strlen.de>
switch (priv->base) {
case NFT_PAYLOAD_LL_HEADER:
- if (!skb_mac_header_was_set(skb))
+ if (!skb_mac_header_was_set(skb) || skb_mac_header_len(skb) == 0)
goto err;
if (skb_vlan_tag_present(skb) &&