| Message ID | 20231008173730.137689-1-fw@strlen.de |
|---|---|
| State | Accepted, archived |
| Headers | show |
| Series | [nf] netfilter: nft_payload: fix wrong mac header matching | expand |
diff --git a/net/netfilter/nft_payload.c b/net/netfilter/nft_payload.c index 120f6d395b98..0a689c8e0295 100644 --- a/net/netfilter/nft_payload.c +++ b/net/netfilter/nft_payload.c @@ -179,7 +179,7 @@ void nft_payload_eval(const struct nft_expr *expr, 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) &&
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> --- net/netfilter/nft_payload.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)