Re: [PATCH net v3] ipv6: sit: fix skb_under_panic with overflowed needed_headroom

[Paolo Abeni]

On 4/1/25 4:16 AM, Wang Liang wrote:
> @@ -1452,7 +1457,9 @@ static int ipip6_tunnel_init(struct net_device *dev)
>  	tunnel->dev = dev;
>  	strcpy(tunnel->parms.name, dev->name);
>  
> -	ipip6_tunnel_bind_dev(dev);
> +	err = ipip6_tunnel_bind_dev(dev);
> +	if (err)
> +		return err;
>  
>  	err = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
>  	if (err)

I think you additionally need to propagate the error in
ipip6_tunnel_update() and handle it in ipip6_changelink() and
ipip6_tunnel_change().

Side note: possibly other virtual devices are prone to similar issue. I
suspect vxlan and gre. Could you please have a look?

Thanks,

Paolo