I’m trying to write a simple network bridge module, got the following rx handler:

static rx_handler_result_t handle_frame(struct sk_buff **pskb) {
    struct sk_buff *skb = *pskb;
    struct sk_buff *cloned_skb;

    // Forward packets from eth1 to eth0
    if (skb->dev == dev_eth1) {
        struct ethhdr *eth = eth_hdr(skb);
        pr_info("Incoming packet: src MAC %pM, dst MAC %pM, ethertype 0x%04xn",
                eth->h_source, eth->h_dest, ntohs(eth->h_proto));
        cloned_skb = skb_clone(skb, GFP_ATOMIC);
        if (!cloned_skb) {
            pr_err("Failed to clone skbn");
            return RX_HANDLER_PASS;
        }
        cloned_skb->dev = dev_eth0;
        //skb_reset_mac_header(cloned_skb);
        // skb_reset_network_header(cloned_skb);
        // skb_reset_transport_header(cloned_skb);

        eth = eth_hdr(cloned_skb);
        pr_info("Sending packet on eth0: src MAC %pM, dst MAC %pM, ethertype 0x%04xn",
                eth->h_source, eth->h_dest, ntohs(eth->h_proto));

        dev_queue_xmit(cloned_skb);


        return RX_HANDLER_CONSUMED;
    }
}

Even though both printk’s are showing same contents, on the wire i see completely garbled frame (even mac addresses are random and also are incrementing, as if cloned_skb data was affecting header).

I’ve checked some of the other kernel drivers, like vlan, they seem to be using similar approach there.

Please any clues on what am i doing wrong.