Re: [Linux-ATM-General] br2684 : sent packets truncated in VC routed mode

[Pascal H. <pa...@pl...>]

chas williams - CONTRACTOR wrote :
> On Thu, 28 Jul 2011 21:10:38 +0200
> Francois Romieu <ro...@fr...> wrote:
> 
>> A short explanation of the skb_pull(skb, ETH_HLEN) for e_vc/p_routed in
>> br2684_xmit_vcc would be welcome.
>>
>> I do not see how there can be ETH_HLEN excess bytes in this direction.
> 
> yeah, i think this skb_pull() is wrong.  when a routed interface is
> setup, it shouldnt be prepending ethernet headers on the outgoing
> packets so there shouldnt be any need to remove an ethernet header.
> 
> anyone willing/capable of testing a patch?

A test with an ADSL line using VC-MUX routed encapsulation for internet
access through a Sagem Fast 800 USB modem (ueagle-atm) was successful.
The internet connection worked fine.

Command line : br2684ctl -c 0 -e 1 -p 0 -a 8.36

Below is a (trivial) patch against kernel 3.0 adapted from the one I
applied to my kernel 2.6.32.

diff -ur a/net/atm/br2684.c b/net/atm/br2684.c
--- a/net/atm/br2684.c	2011-07-30 19:13:26.000000000 +0200
+++ b/net/atm/br2684.c	2011-07-30 19:26:28.000000000 +0200
@@ -242,8 +242,6 @@
 		if (brdev->payload == p_bridged) {
 			skb_push(skb, 2);
 			memset(skb->data, 0, 2);
-		} else { /* p_routed */
-			skb_pull(skb, ETH_HLEN);
 		}
 	}
 	skb_debug(skb);