[PATCH 6.8 021/158] netfilter: flowtable: incorrect pppoe tuple

Greg Kroah-Hartman
2024-04-23T21:41:01Z

From: Pablo Neira Ayuso <pablo@netfilter.org>

[ Upstream commit 6db5dc7b351b9569940cd1cf445e237c42cd6d27 ]

pppoe traffic reaching ingress path does not match the flowtable entry
because the pppoe header is expected to be at the network header offset.
This bug causes a mismatch in the flow table lookup, so pppoe packets
enter the classical forwarding path.

Fixes: 72efd585f714 ("netfilter: flowtable: add pppoe support")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/netfilter/nf_flow_table_ip.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/netfilter/nf_flow_table_ip.c b/net/netfilter/nf_flow_table_ip.c
index 9e9e105052dae..5383bed3d3e00 100644
--- a/net/netfilter/nf_flow_table_ip.c
+++ b/net/netfilter/nf_flow_table_ip.c
@@ -157,7 +157,7 @@ static void nf_flow_tuple_encap(struct sk_buff *skb,
tuple->encap[i].proto = skb->protocol;
break;
case htons(ETH_P_PPP_SES):
- phdr = (struct pppoe_hdr *)skb_mac_header(skb);
+ phdr = (struct pppoe_hdr *)skb_network_header(skb);
tuple->encap[i].id = ntohs(phdr->sid);
tuple->encap[i].proto = skb->protocol;
break;
--
2.43.0