Commit 675071a2 authored Mar 21, 2011 by Eric W. Biederman Committed by David S. Miller Mar 21, 2011

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>

parent 9d2a8fa9

drivers/net/veth.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -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;

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