On Thu, 10 Mar 2022 14:13:28 -0800 Tadeusz Struk wrote:
> diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
> index 4788f6b37053..6d45112322a0 100644
> --- a/net/ipv6/ip6_output.c
> +++ b/net/ipv6/ip6_output.c
> @@ -1649,6 +1649,16 @@ static int __ip6_append_data(struct sock *sk,
> skb->protocol = htons(ETH_P_IPV6);
> skb->ip_summed = csummode;
> skb->csum = 0;
> +
> + /*
> + * Check if there is still room for payload
> + */
TBH I think the check is self-explanatory. Not worth a banner comment,
for sure.
> + if (fragheaderlen >= mtu) {
> + err = -EMSGSIZE;
> + kfree_skb(skb);
> + goto error;
> + }
Not sure if Willem prefers this placement, but seems like we can lift
this check out of the loop, as soon as fragheaderlen and mtu are known.
> /* reserve for fragmentation and ipsec header */
> skb_reserve(skb, hh_len + sizeof(struct frag_hdr) +
> dst_exthdrlen);
