netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Jiri Benc <jbenc@redhat.com>
To: Eric Garver <e@erig.me>
Cc: netdev@vger.kernel.org, ovs-dev@openvswitch.org
Subject: Re: [PATCH net] openvswitch: Fix pop_vlan action for double tagged frames
Date: Tue, 19 Dec 2017 20:39:29 +0100	[thread overview]
Message-ID: <20171219203929.12c1cb93@redhat.com> (raw)
In-Reply-To: <20171219185753.23012-1-e@erig.me>

On Tue, 19 Dec 2017 13:57:53 -0500, Eric Garver wrote:
> --- a/net/openvswitch/flow.c
> +++ b/net/openvswitch/flow.c
> @@ -559,8 +559,9 @@ static int parse_nsh(struct sk_buff *skb, struct sw_flow_key *key)
>   *      of a correct length, otherwise the same as skb->network_header.
>   *      For other key->eth.type values it is left untouched.
>   *
> - *    - skb->protocol: the type of the data starting at skb->network_header.
> - *      Equals to key->eth.type.
> + *    - skb->protocol: For Ethernet, the ethertype or VLAN TPID.
> + *      For non-Ethernet, the type of the data starting at skb->network_header
> + *      (also equal to key->eth.type).
>   */
>  static int key_extract(struct sk_buff *skb, struct sw_flow_key *key)
>  {
> @@ -579,6 +580,7 @@ static int key_extract(struct sk_buff *skb, struct sw_flow_key *key)
>  			return -EINVAL;
>  
>  		skb_reset_network_header(skb);
> +		key->eth.type = skb->protocol;
>  	} else {
>  		eth = eth_hdr(skb);
>  		ether_addr_copy(key->eth.src, eth->h_source);
> @@ -592,15 +594,14 @@ static int key_extract(struct sk_buff *skb, struct sw_flow_key *key)
>  		if (unlikely(parse_vlan(skb, key)))
>  			return -ENOMEM;
>  
> -		skb->protocol = parse_ethertype(skb);
> -		if (unlikely(skb->protocol == htons(0)))
> +		key->eth.type = parse_ethertype(skb);
> +		if (unlikely(key->eth.type == htons(0)))
>  			return -ENOMEM;
>  
>  		skb_reset_network_header(skb);
>  		__skb_push(skb, skb->data - skb_mac_header(skb));
>  	}
>  	skb_reset_mac_len(skb);
> -	key->eth.type = skb->protocol;
>  
>  	/* Network layer. */
>  	if (key->eth.type == htons(ETH_P_IP)) {

Unfortunately, this does not work. key_extract must set skb->protocol
even for Ethernet frames that come from a mixed L2/L3 tunnel. Such
packets will have key->mac_proto set to MAC_PROTO_ETHERNET and
skb->protocol set to ETH_P_TEB (see key_extract_mac_proto). In
key_extract, skb->protocol has to be correctly set to the dissected
value.

Which means that we have to check for the existence of inner vlan tag
(by checking key->eth.cvlan.tci or, perhaps better, by returning it
from parse_vlan) and set skb->protocol accordingly.

 Jiri

  parent reply	other threads:[~2017-12-19 19:39 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-12-19 18:57 [PATCH net] openvswitch: Fix pop_vlan action for double tagged frames Eric Garver
2017-12-19 19:39 ` Jiri Benc
2017-12-19 19:39 ` Jiri Benc [this message]
2017-12-19 20:42   ` Eric Garver
2017-12-19 20:59     ` Eric Garver
2017-12-19 20:42   ` Eric Garver

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20171219203929.12c1cb93@redhat.com \
    --to=jbenc@redhat.com \
    --cc=e@erig.me \
    --cc=netdev@vger.kernel.org \
    --cc=ovs-dev@openvswitch.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).