can: fix WARN_ON dump in net/core/rtnetlink.c:rtmsg_ifinfo()

On older kernels, e.g. 2.6.27, a WARN_ON dump in rtmsg_ifinfo()
is thrown when the CAN device is registered due to insufficient
skb space, as reported by various users. This patch adds the
rtnl_link_ops "get_size" to fix the problem. I think this patch
is required for more recent kernels as well, even if no WARN_ON
dumps are triggered. Maybe we also need "get_xstats_size" for
the CAN xstats.

Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Wolfgang Grandegger 2009-11-06 23:53:13 +00:00 committed by David S. Miller
parent 6755aebaaf
commit 53a0ef866d
1 changed files with 17 additions and 0 deletions

View File

@ -589,6 +589,22 @@ static int can_changelink(struct net_device *dev,
return 0;
}
static size_t can_get_size(const struct net_device *dev)
{
struct can_priv *priv = netdev_priv(dev);
size_t size;
size = nla_total_size(sizeof(u32)); /* IFLA_CAN_STATE */
size += sizeof(struct can_ctrlmode); /* IFLA_CAN_CTRLMODE */
size += nla_total_size(sizeof(u32)); /* IFLA_CAN_RESTART_MS */
size += sizeof(struct can_bittiming); /* IFLA_CAN_BITTIMING */
size += sizeof(struct can_clock); /* IFLA_CAN_CLOCK */
if (priv->bittiming_const) /* IFLA_CAN_BITTIMING_CONST */
size += sizeof(struct can_bittiming_const);
return size;
}
static int can_fill_info(struct sk_buff *skb, const struct net_device *dev)
{
struct can_priv *priv = netdev_priv(dev);
@ -639,6 +655,7 @@ static struct rtnl_link_ops can_link_ops __read_mostly = {
.setup = can_setup,
.newlink = can_newlink,
.changelink = can_changelink,
.get_size = can_get_size,
.fill_info = can_fill_info,
.fill_xstats = can_fill_xstats,
};