Subject: Re: [PATCH net-next v11 17/23] ovpn: add support for peer floating

From: Sabrina Dubroca <[email-masked]>
Date: Mon, 4 Nov 2024 12:24:29 +0100

2024-10-29, 11:47:30 +0100, Antonio Quartulli wrote:
> +static int ovpn_peer_reset_sockaddr(struct ovpn_peer *peer,
> +				    const struct sockaddr_storage *ss,
> +				    const u8 *local_ip)
> +	__must_hold(&peer->lock)
> +{
> +	struct ovpn_bind *bind;
> +	size_t ip_len;
> +
> +	/* create new ovpn_bind object */
> +	bind = ovpn_bind_from_sockaddr(ss);
> +	if (IS_ERR(bind))
> +		return PTR_ERR(bind);
> +
> +	if (local_ip) {
> +		if (ss->ss_family == AF_INET) {
> +			ip_len = sizeof(struct in_addr);
> +		} else if (ss->ss_family == AF_INET6) {
> +			ip_len = sizeof(struct in6_addr);
> +		} else {
> +			netdev_dbg(peer->ovpn->dev, "%s: invalid family for remote endpoint\n",
> +				   __func__);

ratelimited since that can be triggered from packet processing?

[...]
> +void ovpn_peer_float(struct ovpn_peer *peer, struct sk_buff *skb)
> +{
[...]
> +
> +	switch (family) {
> +	case AF_INET:
> +		sa = (struct sockaddr_in *)&ss;
> +		sa->sin_family = AF_INET;
> +		sa->sin_addr.s_addr = ip_hdr(skb)->saddr;
> +		sa->sin_port = udp_hdr(skb)->source;
> +		salen = sizeof(*sa);
> +		break;
> +	case AF_INET6:
> +		sa6 = (struct sockaddr_in6 *)&ss;
> +		sa6->sin6_family = AF_INET6;
> +		sa6->sin6_addr = ipv6_hdr(skb)->saddr;
> +		sa6->sin6_port = udp_hdr(skb)->source;
> +		sa6->sin6_scope_id = ipv6_iface_scope_id(&ipv6_hdr(skb)->saddr,
> +							 skb->skb_iif);
> +		salen = sizeof(*sa6);
> +		break;
> +	default:
> +		goto unlock;
> +	}
> +
> +	netdev_dbg(peer->ovpn->dev, "%s: peer %d floated to %pIScp", __func__,

                                              %u for peer->id?

and ratelimited too, probably.

(also in ovpn_peer_update_local_endpoint in the previous patch)

> +		   peer->id, &ss);
> +	ovpn_peer_reset_sockaddr(peer, (struct sockaddr_storage *)&ss,
> +				 local_ip);

skip the rehash if this fails? peer->bind will still be the old one so
moving it to the new hash chain won't help (the lookup will fail).

-- 
Sabrina