netdev - Re: [PATCH net 1/2] act_ife: Fix external mac header on encode

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Message-ID: <a5dadd53-788e-c02f-7dab-3d1a30088405@mojatatu.com>
Date:   Thu, 22 Sep 2016 19:16:40 -0400
From:   Jamal Hadi Salim <jhs@...atatu.com>
To:     Yotam Gigi <yotamg@...lanox.com>, davem@...emloft.net,
        netdev@...r.kernel.org, Roman Mashak <mrv@...atatu.com>
Subject: Re: [PATCH net 1/2] act_ife: Fix external mac header on encode

On 16-09-22 08:55 AM, Yotam Gigi wrote:
> On ife encode side, external mac header is copied from the original packet
> and may be overridden if the user requests. Before, the mac header copy
> was done from memory region that might not be accessible anymore, as
> skb_cow_head might free it and copy the packet. This led to random values
> in the external mac header once the values were not set by user.
>
> This fix takes the internal mac header from the packet, after the call to
> skb_cow_head.


Since this depends on the previous patch, can you double check for me? I 
will test later, but here's a very simple test case:

sudo $TC qdisc del dev $ETH root handle 1: prio
sudo $TC qdisc add dev $ETH root handle 1: prio

#set mark of decimal 17 and allow sending out
sudo $TC filter add dev $ETH parent 1: protocol ip prio 10 \
u32 match ip protocol 1 0xff flowid 1:2 \
action skbedit mark 17 \
action ife encode \
type 0xDEAD \
allow mark \
dst 02:15:15:15:15:15

I am not going to comment on your other patch, but i suggest you
test with with this (encoding at least two TLVs):

sudo $TC qdisc del dev $ETH root handle 1: prio
sudo $TC qdisc add dev $ETH root handle 1: prio
#Override mark and send prio of 0x33 (unfortunately
#skbedit is not very consistent 33 means 0x33)
sudo $TC filter add dev $ETH parent 1: protocol ip prio 10 \
u32 match ip protocol 1 0xff flowid 1:2 \
action skbedit prio 33 \
action ife encode \
type 0xDEAD \
use mark 12 \
allow prio \
dst 02:15:15:15:15:15


cheers,
jamal