From d4c5fba2f6c272ed687fe6351e5b20bc60cf24f0 Mon Sep 17 00:00:00 2001 From: Ying Xue Date: Wed, 15 Jan 2014 10:23:40 +0800 Subject: [PATCH] decnet: use __dev_get_by_index instead of dev_get_by_index to find interface The following call chain we can identify that dn_cache_getroute() is protected under rtnl_lock. So if we use __dev_get_by_index() instead of dev_get_by_index() to find interface handlers in it, this would help us avoid to change interface reference counter. rtnetlink_rcv() rtnl_lock() netlink_rcv_skb() dn_cache_getroute() rtnl_unlock() Signed-off-by: Ying Xue Signed-off-by: David S. Miller --- net/decnet/dn_route.c | 10 ++-------- 1 file changed, 2 insertions(+), 8 deletions(-) diff --git a/net/decnet/dn_route.c b/net/decnet/dn_route.c index ad2efa5b861b..ce0cbbfe0f43 100644 --- a/net/decnet/dn_route.c +++ b/net/decnet/dn_route.c @@ -1666,12 +1666,8 @@ static int dn_cache_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh) if (fld.flowidn_iif) { struct net_device *dev; - if ((dev = dev_get_by_index(&init_net, fld.flowidn_iif)) == NULL) { - kfree_skb(skb); - return -ENODEV; - } - if (!dev->dn_ptr) { - dev_put(dev); + dev = __dev_get_by_index(&init_net, fld.flowidn_iif); + if (!dev || !dev->dn_ptr) { kfree_skb(skb); return -ENODEV; } @@ -1693,8 +1689,6 @@ static int dn_cache_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh) err = dn_route_output_key((struct dst_entry **)&rt, &fld, 0); } - if (skb->dev) - dev_put(skb->dev); skb->dev = NULL; if (err) goto out_free; -- GitLab