inet: RCU changes in inetdev_by_index()

Convert inetdev_by_index() to not increment in_dev refcount.

Callers hold RCU or RTNL, and should not decrement in_dev refcount.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2010-10-19 00:39:26 +00:00 committed by David S. Miller
parent 9e917dca74
commit 8723e1b4ad
4 changed files with 16 additions and 22 deletions

View File

@ -403,6 +403,9 @@ static int inet_set_ifa(struct net_device *dev, struct in_ifaddr *ifa)
return inet_insert_ifa(ifa);
}
/* Caller must hold RCU or RTNL :
* We dont take a reference on found in_device
*/
struct in_device *inetdev_by_index(struct net *net, int ifindex)
{
struct net_device *dev;
@ -411,7 +414,7 @@ struct in_device *inetdev_by_index(struct net *net, int ifindex)
rcu_read_lock();
dev = dev_get_by_index_rcu(net, ifindex);
if (dev)
in_dev = in_dev_get(dev);
in_dev = rcu_dereference_rtnl(dev->ip_ptr);
rcu_read_unlock();
return in_dev;
}
@ -453,8 +456,6 @@ static int inet_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg
goto errout;
}
__in_dev_put(in_dev);
for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
ifap = &ifa->ifa_next) {
if (tb[IFA_LOCAL] &&

View File

@ -590,32 +590,29 @@ static int fib_check_nh(struct fib_config *cfg, struct fib_info *fi,
if (!dev)
goto out;
dev_hold(dev);
err = -ENETDOWN;
if (!(dev->flags & IFF_UP))
goto out;
err = 0;
out:
rcu_read_unlock();
return err;
err = (dev->flags & IFF_UP) ? 0 : -ENETDOWN;
} else {
struct in_device *in_dev;
if (nh->nh_flags & (RTNH_F_PERVASIVE | RTNH_F_ONLINK))
return -EINVAL;
rcu_read_lock();
err = -ENODEV;
in_dev = inetdev_by_index(net, nh->nh_oif);
if (in_dev == NULL)
return -ENODEV;
if (!(in_dev->dev->flags & IFF_UP)) {
in_dev_put(in_dev);
return -ENETDOWN;
}
goto out;
err = -ENETDOWN;
if (!(in_dev->dev->flags & IFF_UP))
goto out;
nh->nh_dev = in_dev->dev;
dev_hold(nh->nh_dev);
nh->nh_scope = RT_SCOPE_HOST;
in_dev_put(in_dev);
err = 0;
}
return 0;
out:
rcu_read_unlock();
return err;
}
static inline unsigned int fib_laddr_hashfn(__be32 val)

View File

@ -1429,8 +1429,6 @@ static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr)
if (imr->imr_ifindex) {
idev = inetdev_by_index(net, imr->imr_ifindex);
if (idev)
__in_dev_put(idev);
return idev;
}
if (imr->imr_address.s_addr) {

View File

@ -1245,10 +1245,8 @@ static int ipgre_close(struct net_device *dev)
if (ipv4_is_multicast(t->parms.iph.daddr) && t->mlink) {
struct in_device *in_dev;
in_dev = inetdev_by_index(dev_net(dev), t->mlink);
if (in_dev) {
if (in_dev)
ip_mc_dec_group(in_dev, t->parms.iph.daddr);
in_dev_put(in_dev);
}
}
return 0;
}