| Message ID | 0aafb805b5a6a845375b5332f07c96c0d43b08e3.1624572003.git.gnault@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | net: reset MAC header consistently across L3 virtual devices | expand |
diff --git a/drivers/net/bareudp.c b/drivers/net/bareudp.c index edfad93e7b68..a7ee0af1af90 100644 --- a/drivers/net/bareudp.c +++ b/drivers/net/bareudp.c @@ -133,6 +133,7 @@ static int bareudp_udp_encap_recv(struct sock *sk, struct sk_buff *skb) skb->dev = bareudp->dev; oiph = skb_network_header(skb); skb_reset_network_header(skb); + skb_reset_mac_header(skb); if (!IS_ENABLED(CONFIG_IPV6) || family == AF_INET) err = IP_ECN_decapsulate(oiph, skb);
Even though bareudp transports L3 data (typically IP or MPLS), it needs to reset the mac_header pointer, so that other parts of the stack don't mistakenly access the outer header after the packet has been decapsulated. This allows to push an Ethernet header to bareudp packets and redirect them to an Ethernet device: $ tc filter add dev bareudp0 ingress matchall \ action vlan push_eth dst_mac 00:00:5e:00:53:01 \ src_mac 00:00:5e:00:53:00 \ action mirred egress redirect dev eth0 Without this patch, push_eth refuses to add an ethernet header because the skb appears to already have a MAC header. Signed-off-by: Guillaume Nault <gnault@redhat.com> --- drivers/net/bareudp.c | 1 + 1 file changed, 1 insertion(+)