diff -Nur linux-4.1.6.orig/include/linux/netdevice.h linux-4.1.6/include/linux/netdevice.h
--- linux-4.1.6.orig/include/linux/netdevice.h	2015-09-13 22:24:50.977669635 +0200
+++ linux-4.1.6/include/linux/netdevice.h	2015-09-13 22:25:26.259637337 +0200
@@ -1270,6 +1270,7 @@
 	IFF_XMIT_DST_RELEASE_PERM	= 1<<22,
 	IFF_IPVLAN_MASTER		= 1<<23,
 	IFF_IPVLAN_SLAVE		= 1<<24,
+	IFF_NO_IP_ALIGN			= 1<<25,
 };
 
 #define IFF_802_1Q_VLAN			IFF_802_1Q_VLAN
@@ -1297,6 +1298,7 @@
 #define IFF_XMIT_DST_RELEASE_PERM	IFF_XMIT_DST_RELEASE_PERM
 #define IFF_IPVLAN_MASTER		IFF_IPVLAN_MASTER
 #define IFF_IPVLAN_SLAVE		IFF_IPVLAN_SLAVE
+#define IFF_NO_IP_ALIGN			IFF_NO_IP_ALIGN
 
 /**
  *	struct net_device - The DEVICE structure.
@@ -1567,6 +1569,11 @@
 	const struct swdev_ops *swdev_ops;
 #endif
 
+#ifdef CONFIG_ETHERNET_PACKET_MANGLE
+	void (*eth_mangle_rx)(struct net_device *dev, struct sk_buff *skb);
+	struct sk_buff *(*eth_mangle_tx)(struct net_device *dev, struct sk_buff *skb);
+#endif
+
 	const struct header_ops *header_ops;
 
 	unsigned int		flags;
@@ -1631,6 +1638,10 @@
 	struct mpls_dev __rcu	*mpls_ptr;
 #endif
 
+#ifdef CONFIG_ETHERNET_PACKET_MANGLE
+	void			*phy_ptr; /* PHY device specific data */
+#endif
+
 /*
  * Cache lines mostly used on receive path (including eth_type_trans())
  */
diff -Nur linux-4.1.6.orig/include/linux/skbuff.h linux-4.1.6/include/linux/skbuff.h
--- linux-4.1.6.orig/include/linux/skbuff.h	2015-09-13 22:24:50.981669405 +0200
+++ linux-4.1.6/include/linux/skbuff.h	2015-09-13 22:25:26.267636876 +0200
@@ -2068,6 +2068,10 @@
 	return (len < skb->len) ? __pskb_trim(skb, len) : 0;
 }
 
+extern struct sk_buff *__netdev_alloc_skb_ip_align(struct net_device *dev,
+		unsigned int length, gfp_t gfp);
+
+
 /**
  *	pskb_trim_unique - remove end from a paged unique (not cloned) buffer
  *	@skb: buffer to alter
@@ -2176,16 +2180,6 @@
 }
 
 
-static inline struct sk_buff *__netdev_alloc_skb_ip_align(struct net_device *dev,
-		unsigned int length, gfp_t gfp)
-{
-	struct sk_buff *skb = __netdev_alloc_skb(dev, length + NET_IP_ALIGN, gfp);
-
-	if (NET_IP_ALIGN && skb)
-		skb_reserve(skb, NET_IP_ALIGN);
-	return skb;
-}
-
 static inline struct sk_buff *netdev_alloc_skb_ip_align(struct net_device *dev,
 		unsigned int length)
 {
diff -Nur linux-4.1.6.orig/net/core/dev.c linux-4.1.6/net/core/dev.c
--- linux-4.1.6.orig/net/core/dev.c	2015-09-13 22:24:51.109662032 +0200
+++ linux-4.1.6/net/core/dev.c	2015-09-13 22:25:26.267636876 +0200
@@ -2657,10 +2657,20 @@
 	if (!list_empty(&ptype_all) || !list_empty(&dev->ptype_all))
 		dev_queue_xmit_nit(skb, dev);
 
-	len = skb->len;
-	trace_net_dev_start_xmit(skb, dev);
-	rc = netdev_start_xmit(skb, dev, txq, more);
-	trace_net_dev_xmit(skb, rc, dev, len);
+#ifdef CONFIG_ETHERNET_PACKET_MANGLE
+	if (!dev->eth_mangle_tx ||
+	    (skb = dev->eth_mangle_tx(dev, skb)) != NULL)
+#else
+	if (1)
+#endif
+	{
+		len = skb->len;
+		trace_net_dev_start_xmit(skb, dev);
+		rc = netdev_start_xmit(skb, dev, txq, more);
+		trace_net_dev_xmit(skb, rc, dev, len);
+	} else {
+		rc = NETDEV_TX_OK;
+	}
 
 	return rc;
 }
diff -Nur linux-4.1.6.orig/net/core/skbuff.c linux-4.1.6/net/core/skbuff.c
--- linux-4.1.6.orig/net/core/skbuff.c	2015-09-13 22:24:51.113661802 +0200
+++ linux-4.1.6/net/core/skbuff.c	2015-09-13 22:25:49.410303821 +0200
@@ -63,6 +63,7 @@
 #include <linux/errqueue.h>
 #include <linux/prefetch.h>
 #include <linux/if_vlan.h>
+#include <linux/if.h>
 #include <linux/locallock.h>
 
 #include <net/protocol.h>
@@ -570,6 +571,22 @@
 }
 EXPORT_SYMBOL(__napi_alloc_skb);
 
+struct sk_buff *__netdev_alloc_skb_ip_align(struct net_device *dev,
+		unsigned int length, gfp_t gfp)
+{
+	struct sk_buff *skb = __netdev_alloc_skb(dev, length + NET_IP_ALIGN, gfp);
+
+#ifdef CONFIG_ETHERNET_PACKET_MANGLE
+	if (dev && (dev->priv_flags & IFF_NO_IP_ALIGN))
+		return skb;
+#endif
+
+	if (NET_IP_ALIGN && skb)
+		skb_reserve(skb, NET_IP_ALIGN);
+	return skb;
+}
+EXPORT_SYMBOL(__netdev_alloc_skb_ip_align);
+
 void skb_add_rx_frag(struct sk_buff *skb, int i, struct page *page, int off,
 		     int size, unsigned int truesize)
 {
diff -Nur linux-4.1.6.orig/net/ethernet/eth.c linux-4.1.6/net/ethernet/eth.c
--- linux-4.1.6.orig/net/ethernet/eth.c	2015-08-17 05:52:51.000000000 +0200
+++ linux-4.1.6/net/ethernet/eth.c	2015-09-13 22:25:26.271636646 +0200
@@ -155,6 +155,12 @@
 	const struct ethhdr *eth;
 
 	skb->dev = dev;
+
+#ifdef CONFIG_ETHERNET_PACKET_MANGLE
+	if (dev->eth_mangle_rx)
+		dev->eth_mangle_rx(dev, skb);
+#endif
+
 	skb_reset_mac_header(skb);
 	skb_pull_inline(skb, ETH_HLEN);
 	eth = eth_hdr(skb);
diff -Nur linux-4.1.6.orig/net/Kconfig linux-4.1.6/net/Kconfig
--- linux-4.1.6.orig/net/Kconfig	2015-08-17 05:52:51.000000000 +0200
+++ linux-4.1.6/net/Kconfig	2015-09-13 22:25:26.279636185 +0200
@@ -25,6 +25,12 @@
 
 if NET
 
+config ETHERNET_PACKET_MANGLE
+	bool
+	help
+	  This option can be selected by phy drivers that need to mangle
+	  packets going in or out of an ethernet device.
+
 config WANT_COMPAT_NETLINK_MESSAGES
 	bool
 	help