netlink: bug fix: don't overrun skbs on vf_port dump

Noticed by Patrick McHardy: was continuing to fill skb after a
nla_put_failure, ignoring the size calculated by upper layer.  Now,
return -EMSGSIZE on any overruns, but also allow netdev to
fail ndo_get_vf_port with error other than -EMSGSIZE, thus unwinding
nest.

Signed-off-by: Scott Feldman <scofeldm@cisco.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Scott Feldman 2010-05-28 03:42:18 -07:00 committed by David S. Miller
parent 50636af715
commit 8ca9418350

View File

@ -722,14 +722,13 @@ static int rtnl_vf_ports_fill(struct sk_buff *skb, struct net_device *dev)
for (vf = 0; vf < dev_num_vf(dev->dev.parent); vf++) {
vf_port = nla_nest_start(skb, IFLA_VF_PORT);
if (!vf_port) {
nla_nest_cancel(skb, vf_ports);
return -EMSGSIZE;
}
if (!vf_port)
goto nla_put_failure;
NLA_PUT_U32(skb, IFLA_PORT_VF, vf);
err = dev->netdev_ops->ndo_get_vf_port(dev, vf, skb);
if (err == -EMSGSIZE)
goto nla_put_failure;
if (err) {
nla_put_failure:
nla_nest_cancel(skb, vf_port);
continue;
}
@ -739,6 +738,10 @@ nla_put_failure:
nla_nest_end(skb, vf_ports);
return 0;
nla_put_failure:
nla_nest_cancel(skb, vf_ports);
return -EMSGSIZE;
}
static int rtnl_port_self_fill(struct sk_buff *skb, struct net_device *dev)
@ -753,7 +756,7 @@ static int rtnl_port_self_fill(struct sk_buff *skb, struct net_device *dev)
err = dev->netdev_ops->ndo_get_vf_port(dev, PORT_SELF_VF, skb);
if (err) {
nla_nest_cancel(skb, port_self);
return err;
return (err == -EMSGSIZE) ? err : 0;
}
nla_nest_end(skb, port_self);