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veth: Fix the byte counters 

Commit 44540960 "veth: move loopback logic to common location" introduced
a bug in the packet counters.  I don't understand why that happened as it
is not explained in the comments and the mut check in dev_forward_skb
retains the assumption that skb->len is the total length of the packet.

I just measured this emperically by setting up a veth pair between two
noop network namespaces setting and attempting a telnet connection between
the two.  I saw three packets in each direction and the byte counters were
exactly 14*3 = 42 bytes high in each direction.  I got the actual
packet lengths with tcpdump.

So remove the extra ETH_HLEN from the veth byte count totals.

Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric W. Biederman 2011-03-21 18:24:53 -07:00 committed by David S. Miller
parent 9d2a8fa96a
commit 675071a2ef
1 changed files with 1 additions and 1 deletions
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2
drivers/net/veth.c
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@ -171,7 +171,7 @@ static netdev_tx_t veth_xmit(struct sk_buff *skb, struct net_device *dev)
if (skb->ip_summed == CHECKSUM_NONE)
skb->ip_summed = rcv_priv->ip_summed;
length = skb->len + ETH_HLEN;
length = skb->len;
if (dev_forward_skb(rcv, skb) != NET_RX_SUCCESS)
goto rx_drop;