[PATCH net-next 06/10] vxlan: use __dev_get_by_index instead of dev_get_by_index to find interface

Ying Xue
2014-01-14T07:42:43Z

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>
---
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