bpf: Set mac_len in bpf_skb_change_head

The skb_change_head() helper did not set "skb->mac_len", which is
problematic when it's used in combination with skb_redirect_peer().
Without it, redirecting a packet from a L3 device such as wireguard to
the veth peer device will cause skb->data to point to the middle of the
IP header on entry to tcp_v4_rcv() since the L2 header is not pulled
correctly due to mac_len=0.

Fixes: 3a0af8fd61f9 ("bpf: BPF for lightweight tunnel infrastructure")
Signed-off-by: Jussi Maki <[email protected]>
Signed-off-by: Daniel Borkmann <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]

0 files changed, 0 insertions, 0 deletions