On Tuesday, 27 December 2022 20:34:09 CET Linus Lüssing wrote:
> +/**
> + * batadv_mcast_forw_shrink_move_headers() - move multicast headers by offset
> + * @skb: the batman-adv multicast packet to move headers for
> + * @offset: a non-negative offset to move headers by, towards the skb tail
> + *
> + * Moves the batman-adv multicast packet header, its multicast tracker TVLV and
> + * any TVLVs in between by the given offset in direction towards the tail.
> + *
> + * It also invalidates the skb checksum.
> + */
> +static void
> +batadv_mcast_forw_shrink_move_headers(struct sk_buff *skb, unsigned int offset)
> +{
> +       struct batadv_tvlv_mcast_tracker *mcast_tracker;
> +       unsigned int tracker_hdrlen, len;
> +       unsigned char *skb_net_hdr;
> +       u16 num_dests;
> +
> +       skb_net_hdr = skb_network_header(skb);
> +       mcast_tracker = (struct batadv_tvlv_mcast_tracker *)skb_net_hdr;
> +       num_dests = ntohs(mcast_tracker->num_dests);
> +       tracker_hdrlen = batadv_mcast_forw_tracker_hdrlen(num_dests);
> +       len = skb_network_offset(skb) + tracker_hdrlen;
> +
> +       memmove(skb->data + offset, skb->data, len);
> +       skb_pull(skb, offset);
> +
> +       /* invalidate checksum: */
> +       skb->ip_summed = CHECKSUM_NONE;


Shouldn't the invalidation be that already part of the patch 3? At least it 
includes receive path processing and modification on the tvlv with the 
destination originator addresses.

Kind regards,
	Sven