Subject: Re: [PATCH net-next v18 09/25] ovpn: implement packet processing

From: Sabrina Dubroca <[email-masked]>
Date: Fri, 17 Jan 2025 13:16:50 +0100

2025-01-13, 10:31:28 +0100, Antonio Quartulli wrote:
>  static bool ovpn_encrypt_one(struct ovpn_peer *peer, struct sk_buff *skb)
>  {
> -	ovpn_skb_cb(skb)->peer = peer;
> +	struct ovpn_crypto_key_slot *ks;
> +
> +	if (unlikely(skb->ip_summed == CHECKSUM_PARTIAL &&
> +		     skb_checksum_help(skb))) {
> +		net_warn_ratelimited("%s: cannot compute checksum for outgoing packet for peer %u\n",
> +				     netdev_name(peer->ovpn->dev), peer->id);
> +		return false;
> +	}
> +
> +	/* get primary key to be used for encrypting data */
> +	ks = ovpn_crypto_key_slot_primary(&peer->crypto);
> +	if (unlikely(!ks))
> +		return false;
>  
>  	/* take a reference to the peer because the crypto code may run async.
>  	 * ovpn_encrypt_post() will release it upon completion
> @@ -118,7 +244,8 @@ static bool ovpn_encrypt_one(struct ovpn_peer *peer, struct sk_buff *skb)

Adding in the few lines that got snipped:

	/* take a reference to the peer because the crypto code may run async.
	 * ovpn_encrypt_post() will release it upon completion
	 */
	if (unlikely(!ovpn_peer_hold(peer))) {
		DEBUG_NET_WARN_ON_ONCE(1);
		return false;
	}

This should never happen, but just in case, we'd want
ovpn_crypto_key_slot_put() here.

>  		return false;
>  	}

-- 
Sabrina