lkml.org 
[lkml]   [2022]   [Jul]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH net-next v2] ip_tunnel: allow to inherit from VLAN encapsulated IP frames
Hi,

On Wed, Jul 6, 2022 at 7:54 PM Matthias May <matthias.may@westermo.com> wrote:
>
> The current code allows to inherit the TOS, TTL, DF from the payload
> when skb->protocol is ETH_P_IP or ETH_P_IPV6.
> However when the payload is VLAN encapsulated (e.g because the tunnel
> is of type GRETAP), then this inheriting does not work, because the
> visible skb->protocol is of type ETH_P_8021Q.
>
> Add a check on ETH_P_8021Q and subsequently check the payload protocol.
>
> Signed-off-by: Matthias May <matthias.may@westermo.com>
> ---
> v1 -> v2:
> - Add support for ETH_P_8021AD as suggested by Jakub Kicinski.
> ---
> net/ipv4/ip_tunnel.c | 22 ++++++++++++++--------
> 1 file changed, 14 insertions(+), 8 deletions(-)
>
> diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c
> index 94017a8c3994..bdcc0f1e83c8 100644
> --- a/net/ipv4/ip_tunnel.c
> +++ b/net/ipv4/ip_tunnel.c
> @@ -648,6 +648,13 @@ void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
> u8 tos, ttl;
> __be32 dst;
> __be16 df;
> + __be16 *payload_protocol;
> +
> + if (skb->protocol == htons(ETH_P_8021Q) ||
> + skb->protocol == htons(ETH_P_8021AD))
> + payload_protocol = (__be16 *)(skb->head + skb->network_header - 2);
> + else
> + payload_protocol = &skb->protocol;

Maybe it's better to use skb_protocol(skb, true) here instead of open
coding the vlan parsing?

Eyal

\
 
 \ /
  Last update: 2022-07-06 19:26    [W:4.659 / U:0.084 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site