From: Ben Greear <greearb@candelatech.com>
Date: Thu, 21 Oct 2010 11:06:29 +0000 (-0700)
Subject: net/core: Allow tagged VLAN packets to flow through VETH devices.
X-Git-Tag: firefly_0821_release~7613^2~3670^2~2^2~2
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=d2ed817766987fd05e69b7da65d4861b38f1aa2a;p=firefly-linux-kernel-4.4.55.git

net/core: Allow tagged VLAN packets to flow through VETH devices.

When there are VLANs on a VETH device, the packets being transmitted
through the VETH device may be 4 bytes bigger than MTU.  A check
in dev_forward_skb did not take this into account and so dropped
these packets.

This patch is needed at least as far back as 2.6.34.7 and should
be considered for -stable.

Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/core/dev.c b/net/core/dev.c
index 660dd41aaaa6..8e07109cc0ef 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1485,7 +1485,7 @@ int dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
 	nf_reset(skb);
 
 	if (!(dev->flags & IFF_UP) ||
-	    (skb->len > (dev->mtu + dev->hard_header_len))) {
+	    (skb->len > (dev->mtu + dev->hard_header_len + VLAN_HLEN))) {
 		kfree_skb(skb);
 		return NET_RX_DROP;
 	}