Re: [PATCH v3 1/2] ip_tunnel: fix potential issue in ip_tunnel_rcv

[Eric Dumazet]

On Thu, 2017-06-08 at 12:32 +0800, Haishuang Yan wrote:
> When ip_tunnel_rcv fails, the tun_dst won't be freed, so call
> dst_release to free it in error code path.
> 
> CC: Pravin B Shelar <pshelar@xxxxxxxxxx>
> Fixes: 2e15ea390e6f ("ip_gre: Add support to collect tunnel metadata.")
> Signed-off-by: Haishuang Yan <yanhaishuang@xxxxxxxxxxxxxxxxxxxx>
> 
> ---
> Changes in v2:
>   - Add the the missing Fixes information
> Changes in v3:
>   - Free tun_dst from error code path
> ---
>  net/ipv4/ip_tunnel.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c
> index b878ecb..0f1d876 100644
> --- a/net/ipv4/ip_tunnel.c
> +++ b/net/ipv4/ip_tunnel.c
> @@ -446,6 +446,8 @@ int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb,
>  	return 0;
>  
>  drop:
> +	if (tun_dst)
> +		dst_release((struct dst_entry *)tun_dst);
>  	kfree_skb(skb);
>  	return 0;
>  }

Acked-by: Eric Dumazet <edumazet@xxxxxxxxxx>