4497b0763c
Add skb_warn_if_lro() to test whether an skb was received with LRO and warn if so. Change br_forward(), ip_forward() and ip6_forward() to call it) and discard the skb if it returns true. Signed-off-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
148 lines
3.2 KiB
C
148 lines
3.2 KiB
C
/*
|
|
* Forwarding decision
|
|
* Linux ethernet bridge
|
|
*
|
|
* Authors:
|
|
* Lennert Buytenhek <buytenh@gnu.org>
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the License, or (at your option) any later version.
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/netdevice.h>
|
|
#include <linux/skbuff.h>
|
|
#include <linux/if_vlan.h>
|
|
#include <linux/netfilter_bridge.h>
|
|
#include "br_private.h"
|
|
|
|
/* Don't forward packets to originating port or forwarding diasabled */
|
|
static inline int should_deliver(const struct net_bridge_port *p,
|
|
const struct sk_buff *skb)
|
|
{
|
|
return (skb->dev != p->dev && p->state == BR_STATE_FORWARDING);
|
|
}
|
|
|
|
static inline unsigned packet_length(const struct sk_buff *skb)
|
|
{
|
|
return skb->len - (skb->protocol == htons(ETH_P_8021Q) ? VLAN_HLEN : 0);
|
|
}
|
|
|
|
int br_dev_queue_push_xmit(struct sk_buff *skb)
|
|
{
|
|
/* drop mtu oversized packets except gso */
|
|
if (packet_length(skb) > skb->dev->mtu && !skb_is_gso(skb))
|
|
kfree_skb(skb);
|
|
else {
|
|
/* ip_refrag calls ip_fragment, doesn't copy the MAC header. */
|
|
if (nf_bridge_maybe_copy_header(skb))
|
|
kfree_skb(skb);
|
|
else {
|
|
skb_push(skb, ETH_HLEN);
|
|
|
|
dev_queue_xmit(skb);
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
int br_forward_finish(struct sk_buff *skb)
|
|
{
|
|
return NF_HOOK(PF_BRIDGE, NF_BR_POST_ROUTING, skb, NULL, skb->dev,
|
|
br_dev_queue_push_xmit);
|
|
|
|
}
|
|
|
|
static void __br_deliver(const struct net_bridge_port *to, struct sk_buff *skb)
|
|
{
|
|
skb->dev = to->dev;
|
|
NF_HOOK(PF_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
|
|
br_forward_finish);
|
|
}
|
|
|
|
static void __br_forward(const struct net_bridge_port *to, struct sk_buff *skb)
|
|
{
|
|
struct net_device *indev;
|
|
|
|
indev = skb->dev;
|
|
skb->dev = to->dev;
|
|
skb_forward_csum(skb);
|
|
|
|
NF_HOOK(PF_BRIDGE, NF_BR_FORWARD, skb, indev, skb->dev,
|
|
br_forward_finish);
|
|
}
|
|
|
|
/* called with rcu_read_lock */
|
|
void br_deliver(const struct net_bridge_port *to, struct sk_buff *skb)
|
|
{
|
|
if (should_deliver(to, skb)) {
|
|
__br_deliver(to, skb);
|
|
return;
|
|
}
|
|
|
|
kfree_skb(skb);
|
|
}
|
|
|
|
/* called with rcu_read_lock */
|
|
void br_forward(const struct net_bridge_port *to, struct sk_buff *skb)
|
|
{
|
|
if (!skb_warn_if_lro(skb) && should_deliver(to, skb)) {
|
|
__br_forward(to, skb);
|
|
return;
|
|
}
|
|
|
|
kfree_skb(skb);
|
|
}
|
|
|
|
/* called under bridge lock */
|
|
static void br_flood(struct net_bridge *br, struct sk_buff *skb,
|
|
void (*__packet_hook)(const struct net_bridge_port *p,
|
|
struct sk_buff *skb))
|
|
{
|
|
struct net_bridge_port *p;
|
|
struct net_bridge_port *prev;
|
|
|
|
prev = NULL;
|
|
|
|
list_for_each_entry_rcu(p, &br->port_list, list) {
|
|
if (should_deliver(p, skb)) {
|
|
if (prev != NULL) {
|
|
struct sk_buff *skb2;
|
|
|
|
if ((skb2 = skb_clone(skb, GFP_ATOMIC)) == NULL) {
|
|
br->dev->stats.tx_dropped++;
|
|
kfree_skb(skb);
|
|
return;
|
|
}
|
|
|
|
__packet_hook(prev, skb2);
|
|
}
|
|
|
|
prev = p;
|
|
}
|
|
}
|
|
|
|
if (prev != NULL) {
|
|
__packet_hook(prev, skb);
|
|
return;
|
|
}
|
|
|
|
kfree_skb(skb);
|
|
}
|
|
|
|
|
|
/* called with rcu_read_lock */
|
|
void br_flood_deliver(struct net_bridge *br, struct sk_buff *skb)
|
|
{
|
|
br_flood(br, skb, __br_deliver);
|
|
}
|
|
|
|
/* called under bridge lock */
|
|
void br_flood_forward(struct net_bridge *br, struct sk_buff *skb)
|
|
{
|
|
br_flood(br, skb, __br_forward);
|
|
}
|