Re: [PATCH net] adding missing rcu_read_unlock in ipxip6_rcv

[Nikita Shirokov]

On 12/6/17, 12:50 PM, "David Miller"  wrote:

From: "Nikita V. Shirokov" 
Date: Wed,  6 Dec 2017 10:19:33 -0800

> commit 8d79266bc48c ("ip6_tunnel: add collect_md mode to IPv6 tunnels")
> introduced new exit point in  ipxip6_rcv. however rcu_read_unlock is
> missing there. this diff is fixing this
> 
> Signed-off-by: Nikita V. Shirokov 
 ...
> @@ -903,8 +903,10 @@ static int ipxip6_rcv(struct sk_buff *skb, u8 
ipproto,
>   goto drop;
>   if (t->parms.collect_md) {
>   tun_dst = ipv6_tun_rx_dst(skb, 0, 0, 0);
> - if (!tun_dst)
> + if (!tun_dst) {
> + rcu_read_unlock();
>   return 0;
> + }
>   }
>   ret = __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate,
>   log_ecn_error);

Shouldn't it branch to 'drop' otherwise we leak the skb?


Fair point, will rework.

--
Nikita

Re: [PATCH net] adding missing rcu_read_unlock in ipxip6_rcv

[David Miller]

From: "Nikita V. Shirokov" 
Date: Wed,  6 Dec 2017 10:19:33 -0800

> commit 8d79266bc48c ("ip6_tunnel: add collect_md mode to IPv6 tunnels")
> introduced new exit point in  ipxip6_rcv. however rcu_read_unlock is
> missing there. this diff is fixing this
> 
> Signed-off-by: Nikita V. Shirokov 
 ...
> @@ -903,8 +903,10 @@ static int ipxip6_rcv(struct sk_buff *skb, u8 ipproto,
>   goto drop;
>   if (t->parms.collect_md) {
>   tun_dst = ipv6_tun_rx_dst(skb, 0, 0, 0);
> - if (!tun_dst)
> + if (!tun_dst) {
> + rcu_read_unlock();
>   return 0;
> + }
>   }
>   ret = __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate,
>   log_ecn_error);

Shouldn't it branch to 'drop' otherwise we leak the skb?