On Mon, 7 Feb 2022 16:41:01 +0200 Paul Blakey wrote:
> Ipv6 ttl, label and tos fields are modified without first
> pulling/pushing the ipv6 header, which would have updated
> the hw csum (if available). This might cause csum validation
> when sending the packet to the stack, as can be seen in
> the trace below.
>
> Fix this by calling postpush/postpull checksum calculation
> which will update the hw csum if needed.
> -static void set_ipv6_fl(struct ipv6hdr *nh, u32 fl, u32 mask)
> +static void set_ipv6_dsfield(struct sk_buff *skb, struct ipv6hdr *nh, __u8
> ipv6_tclass, __u8 mask)
> {
> + skb_postpull_rcsum(skb, nh, 4);
> +
> + ipv6_change_dsfield(nh, ~mask, ipv6_tclass);
> +
> + skb_postpush_rcsum(skb, nh, 4);
> +}
The calls seem a little heavy for single byte replacements.
Can you instead add a helper based on csum_replace4() maybe?
BTW doesn't pedit have the same problem?
_______________________________________________
dev mailing list
[email protected]
https://mail.openvswitch.org/mailman/listinfo/ovs-dev
