linux/net/8021q/vlan_core.c
Herbert Xu 4ead443163 netpoll: Add drop checks to all entry points
The netpoll entry checks are required to ensure that we don't
receive normal packets when invoked via netpoll.  Unfortunately
it only ever worked for the netif_receive_skb/netif_rx entry
points.  The VLAN (and subsequently GRO) entry point didn't
have the check and therefore can trigger all sorts of weird
problems.

This patch adds the netpoll check to all entry points.

I'm still uneasy with receiving at all under netpoll (which
apparently is only used by the out-of-tree kdump code).  The
reason is it is perfectly legal to receive all data including
headers into highmem if netpoll is off, but if you try to do
that with netpoll on and someone gets a printk in an IRQ handler                                             
you're going to get a nice BUG_ON.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-01 00:11:52 -08:00

158 lines
3.2 KiB
C

#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/if_vlan.h>
#include <linux/netpoll.h>
#include "vlan.h"
/* VLAN rx hw acceleration helper. This acts like netif_{rx,receive_skb}(). */
int __vlan_hwaccel_rx(struct sk_buff *skb, struct vlan_group *grp,
u16 vlan_tci, int polling)
{
if (netpoll_rx(skb))
return NET_RX_DROP;
if (skb_bond_should_drop(skb))
goto drop;
skb->vlan_tci = vlan_tci;
skb->dev = vlan_group_get_device(grp, vlan_tci & VLAN_VID_MASK);
if (!skb->dev)
goto drop;
return (polling ? netif_receive_skb(skb) : netif_rx(skb));
drop:
dev_kfree_skb_any(skb);
return NET_RX_DROP;
}
EXPORT_SYMBOL(__vlan_hwaccel_rx);
int vlan_hwaccel_do_receive(struct sk_buff *skb)
{
struct net_device *dev = skb->dev;
struct net_device_stats *stats;
skb->dev = vlan_dev_info(dev)->real_dev;
netif_nit_deliver(skb);
skb->dev = dev;
skb->priority = vlan_get_ingress_priority(dev, skb->vlan_tci);
skb->vlan_tci = 0;
stats = &dev->stats;
stats->rx_packets++;
stats->rx_bytes += skb->len;
switch (skb->pkt_type) {
case PACKET_BROADCAST:
break;
case PACKET_MULTICAST:
stats->multicast++;
break;
case PACKET_OTHERHOST:
/* Our lower layer thinks this is not local, let's make sure.
* This allows the VLAN to have a different MAC than the
* underlying device, and still route correctly. */
if (!compare_ether_addr(eth_hdr(skb)->h_dest,
dev->dev_addr))
skb->pkt_type = PACKET_HOST;
break;
};
return 0;
}
struct net_device *vlan_dev_real_dev(const struct net_device *dev)
{
return vlan_dev_info(dev)->real_dev;
}
EXPORT_SYMBOL(vlan_dev_real_dev);
u16 vlan_dev_vlan_id(const struct net_device *dev)
{
return vlan_dev_info(dev)->vlan_id;
}
EXPORT_SYMBOL(vlan_dev_vlan_id);
static int vlan_gro_common(struct napi_struct *napi, struct vlan_group *grp,
unsigned int vlan_tci, struct sk_buff *skb)
{
struct sk_buff *p;
if (skb_bond_should_drop(skb))
goto drop;
skb->vlan_tci = vlan_tci;
skb->dev = vlan_group_get_device(grp, vlan_tci & VLAN_VID_MASK);
if (!skb->dev)
goto drop;
for (p = napi->gro_list; p; p = p->next) {
NAPI_GRO_CB(p)->same_flow = p->dev == skb->dev;
NAPI_GRO_CB(p)->flush = 0;
}
return dev_gro_receive(napi, skb);
drop:
return 2;
}
int vlan_gro_receive(struct napi_struct *napi, struct vlan_group *grp,
unsigned int vlan_tci, struct sk_buff *skb)
{
int err = NET_RX_SUCCESS;
if (netpoll_receive_skb(skb))
return NET_RX_DROP;
switch (vlan_gro_common(napi, grp, vlan_tci, skb)) {
case -1:
return netif_receive_skb(skb);
case 2:
err = NET_RX_DROP;
/* fall through */
case 1:
kfree_skb(skb);
break;
}
return err;
}
EXPORT_SYMBOL(vlan_gro_receive);
int vlan_gro_frags(struct napi_struct *napi, struct vlan_group *grp,
unsigned int vlan_tci, struct napi_gro_fraginfo *info)
{
struct sk_buff *skb = napi_fraginfo_skb(napi, info);
int err = NET_RX_DROP;
if (!skb)
goto out;
if (netpoll_receive_skb(skb))
goto out;
err = NET_RX_SUCCESS;
switch (vlan_gro_common(napi, grp, vlan_tci, skb)) {
case -1:
return netif_receive_skb(skb);
case 2:
err = NET_RX_DROP;
/* fall through */
case 1:
napi_reuse_skb(napi, skb);
break;
}
out:
return err;
}
EXPORT_SYMBOL(vlan_gro_frags);