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 <step...@networkplumber.org>
Signed-off-by: Ying Xue <ying....@windriver.com>
---
 drivers/net/vxlan.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index 481f85d..8c40802 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -741,10 +741,9 @@ static int vxlan_fdb_parse(struct nlattr *tb[], struct 
vxlan_dev *vxlan,
                if (nla_len(tb[NDA_IFINDEX]) != sizeof(u32))
                        return -EINVAL;
                *ifindex = nla_get_u32(tb[NDA_IFINDEX]);
-               tdev = dev_get_by_index(net, *ifindex);
+               tdev = __dev_get_by_index(net, *ifindex);
                if (!tdev)
                        return -EADDRNOTAVAIL;
-               dev_put(tdev);
        } else {
                *ifindex = 0;
        }
-- 
1.7.9.5

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