Commit 73763949 authored Jan 15, 2014 by Ying Xue Committed by David S. Miller Jan 14, 2014

vxlan: use __dev_get_by_index instead of dev_get_by_index to find interface



The following call chains indicate that vxlan_fdb_parse() is
under rtnl_lock protection. So if we use __dev_get_by_index()
instead of dev_get_by_index() to find interface handler in it,
this would help us avoid to change interface reference counter.

rtnetlink_rcv()
  rtnl_lock()
  netlink_rcv_skb()
    rtnl_fdb_add()
      vxlan_fdb_add()
        vxlan_fdb_parse()
  rtnl_unlock()

rtnetlink_rcv()
  rtnl_lock()
  netlink_rcv_skb()
    rtnl_fdb_del()
      vxlan_fdb_del()
        vxlan_fdb_parse()
  rtnl_unlock()

Cc: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent d4c5fba2

drivers/net/vxlan.c

+1 −2

Original line number	Original line	Diff line number	Diff line
	@@ -741,10 +741,9 @@ static int vxlan_fdb_parse(struct nlattr tb[], struct vxlan_dev vxlan,
	if (nla_len(tb[NDA_IFINDEX]) != sizeof(u32))		if (nla_len(tb[NDA_IFINDEX]) != sizeof(u32))
	return -EINVAL;		return -EINVAL;
	*ifindex = nla_get_u32(tb[NDA_IFINDEX]);		*ifindex = nla_get_u32(tb[NDA_IFINDEX]);
	tdev = dev_get_by_index(net, *ifindex);		tdev = __dev_get_by_index(net, *ifindex);
	if (!tdev)		if (!tdev)
	return -EADDRNOTAVAIL;		return -EADDRNOTAVAIL;
	dev_put(tdev);
	} else {		} else {
	*ifindex = 0;		*ifindex = 0;
	}		}