Commit 96b52e61 authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

ipv6: mcast: RCU conversions 



- ipv6_sock_mc_join() : doesnt touch dev refcount

- ipv6_sock_mc_drop() : doesnt touch dev/idev refcounts

- ip6_mc_find_dev() becomes ip6_mc_find_dev_rcu() (called from rcu),
                    and doesnt touch dev/idev refcounts

- ipv6_sock_mc_close() : doesnt touch dev/idev refcounts

- ip6_mc_source() uses ip6_mc_find_dev_rcu()

- ip6_mc_msfilter() uses ip6_mc_find_dev_rcu()

- ip6_mc_msfget() uses ip6_mc_find_dev_rcu()

- ipv6_dev_mc_dec(), ipv6_chk_mcast_addr(),
  igmp6_event_query(), igmp6_event_report(),
  mld_sendpack(), igmp6_send() dont touch idev refcount

Signed-off-by: default avatarEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 97859160

net/ipv6/mcast.c

+87 −96
Original line number Diff line number Diff line
@@ -152,18 +152,19 @@ int ipv6_sock_mc_join(struct sock *sk, int ifindex, const struct in6_addr *addr) 
	mc_lst->next = NULL;

	ipv6_addr_copy(&mc_lst->addr, addr);



	rcu_read_lock();

	if (ifindex == 0) {

		struct rt6_info *rt;

		rt = rt6_lookup(net, addr, NULL, 0, 0);

		if (rt) {

			dev = rt->rt6i_dev;

			dev_hold(dev);

			dst_release(&rt->u.dst);

		}

	} else

		dev = dev_get_by_index(net, ifindex);

		dev = dev_get_by_index_rcu(net, ifindex);



	if (dev == NULL) {

		rcu_read_unlock();

		sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));

		return -ENODEV;

	}
@@ -180,8 +181,8 @@ int ipv6_sock_mc_join(struct sock *sk, int ifindex, const struct in6_addr *addr) 
	err = ipv6_dev_mc_inc(dev, addr);



	if (err) {

		rcu_read_unlock();

		sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));

		dev_put(dev);

		return err;

	}
@@ -190,7 +191,7 @@ int ipv6_sock_mc_join(struct sock *sk, int ifindex, const struct in6_addr *addr) 
	np->ipv6_mc_list = mc_lst;

	write_unlock_bh(&ipv6_sk_mc_lock);



	dev_put(dev);

	rcu_read_unlock();



	return 0;

}
@@ -213,18 +214,17 @@ int ipv6_sock_mc_drop(struct sock *sk, int ifindex, const struct in6_addr *addr) 
			*lnk = mc_lst->next;

			write_unlock_bh(&ipv6_sk_mc_lock);



			dev = dev_get_by_index(net, mc_lst->ifindex);

			rcu_read_lock();

			dev = dev_get_by_index_rcu(net, mc_lst->ifindex);

			if (dev != NULL) {

				struct inet6_dev *idev = in6_dev_get(dev);

				struct inet6_dev *idev = __in6_dev_get(dev);



				(void) ip6_mc_leave_src(sk, mc_lst, idev);

				if (idev) {

				if (idev)

					__ipv6_dev_mc_dec(idev, &mc_lst->addr);

					in6_dev_put(idev);

				}

				dev_put(dev);

			} else

				(void) ip6_mc_leave_src(sk, mc_lst, NULL);

			rcu_read_unlock();

			sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));

			return 0;

		}
@@ -234,7 +234,8 @@ int ipv6_sock_mc_drop(struct sock *sk, int ifindex, const struct in6_addr *addr) 
	return -EADDRNOTAVAIL;

}



static struct inet6_dev *ip6_mc_find_dev(struct net *net,

/* called with rcu_read_lock() */

static struct inet6_dev *ip6_mc_find_dev_rcu(struct net *net,

					     struct in6_addr *group,

					     int ifindex)

{
@@ -242,36 +243,28 @@ static struct inet6_dev *ip6_mc_find_dev(struct net *net, 
	struct inet6_dev *idev = NULL;



	if (ifindex == 0) {

		struct rt6_info *rt;

		struct rt6_info *rt = rt6_lookup(net, group, NULL, 0, 0);



		rt = rt6_lookup(net, group, NULL, 0, 0);

		if (rt) {

			dev = rt->rt6i_dev;

			dev_hold(dev);

			dst_release(&rt->u.dst);

		}

	} else

		dev = dev_get_by_index(net, ifindex);

		dev = dev_get_by_index_rcu(net, ifindex);



	if (!dev)

		goto nodev;

	idev = in6_dev_get(dev);

		return NULL;

	idev = __in6_dev_get(dev);

	if (!idev)

		goto release;

		return NULL;;

	read_lock_bh(&idev->lock);

	if (idev->dead)

		goto unlock_release;



	return idev;



unlock_release:

	if (idev->dead) {

		read_unlock_bh(&idev->lock);

	in6_dev_put(idev);

release:

	dev_put(dev);

nodev:

		return NULL;

	}

	return idev;

}



void ipv6_sock_mc_close(struct sock *sk)

{
@@ -286,19 +279,17 @@ void ipv6_sock_mc_close(struct sock *sk) 
		np->ipv6_mc_list = mc_lst->next;

		write_unlock_bh(&ipv6_sk_mc_lock);



		dev = dev_get_by_index(net, mc_lst->ifindex);

		rcu_read_lock();

		dev = dev_get_by_index_rcu(net, mc_lst->ifindex);

		if (dev) {

			struct inet6_dev *idev = in6_dev_get(dev);

			struct inet6_dev *idev = __in6_dev_get(dev);



			(void) ip6_mc_leave_src(sk, mc_lst, idev);

			if (idev) {

			if (idev)

				__ipv6_dev_mc_dec(idev, &mc_lst->addr);

				in6_dev_put(idev);

			}

			dev_put(dev);

		} else

			(void) ip6_mc_leave_src(sk, mc_lst, NULL);



		rcu_read_unlock();

		sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));



		write_lock_bh(&ipv6_sk_mc_lock);
@@ -327,14 +318,17 @@ int ip6_mc_source(int add, int omode, struct sock *sk, 
	if (!ipv6_addr_is_multicast(group))

		return -EINVAL;



	idev = ip6_mc_find_dev(net, group, pgsr->gsr_interface);

	if (!idev)

	rcu_read_lock();

	idev = ip6_mc_find_dev_rcu(net, group, pgsr->gsr_interface);

	if (!idev) {

		rcu_read_unlock();

		return -ENODEV;

	}

	dev = idev->dev;



	err = -EADDRNOTAVAIL;



	read_lock_bh(&ipv6_sk_mc_lock);

	read_lock(&ipv6_sk_mc_lock);

	for (pmc=inet6->ipv6_mc_list; pmc; pmc=pmc->next) {

		if (pgsr->gsr_interface && pmc->ifindex != pgsr->gsr_interface)

			continue;
@@ -358,7 +352,7 @@ int ip6_mc_source(int add, int omode, struct sock *sk, 
		pmc->sfmode = omode;

	}



	write_lock_bh(&pmc->sflock);

	write_lock(&pmc->sflock);

	pmclocked = 1;



	psl = pmc->sflist;
@@ -433,11 +427,10 @@ int ip6_mc_source(int add, int omode, struct sock *sk, 
	ip6_mc_add_src(idev, group, omode, 1, source, 1);

done:

	if (pmclocked)

		write_unlock_bh(&pmc->sflock);

	read_unlock_bh(&ipv6_sk_mc_lock);

		write_unlock(&pmc->sflock);

	read_unlock(&ipv6_sk_mc_lock);

	read_unlock_bh(&idev->lock);

	in6_dev_put(idev);

	dev_put(dev);

	rcu_read_unlock();

	if (leavegroup)

		return ipv6_sock_mc_drop(sk, pgsr->gsr_interface, group);

	return err;
@@ -463,14 +456,17 @@ int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf) 
	    gsf->gf_fmode != MCAST_EXCLUDE)

		return -EINVAL;



	idev = ip6_mc_find_dev(net, group, gsf->gf_interface);

	rcu_read_lock();

	idev = ip6_mc_find_dev_rcu(net, group, gsf->gf_interface);



	if (!idev)

	if (!idev) {

		rcu_read_unlock();

		return -ENODEV;

	}

	dev = idev->dev;



	err = 0;

	read_lock_bh(&ipv6_sk_mc_lock);

	read_lock(&ipv6_sk_mc_lock);



	if (gsf->gf_fmode == MCAST_INCLUDE && gsf->gf_numsrc == 0) {

		leavegroup = 1;
@@ -512,7 +508,7 @@ int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf) 
		(void) ip6_mc_add_src(idev, group, gsf->gf_fmode, 0, NULL, 0);

	}



	write_lock_bh(&pmc->sflock);

	write_lock(&pmc->sflock);

	psl = pmc->sflist;

	if (psl) {

		(void) ip6_mc_del_src(idev, group, pmc->sfmode,
@@ -522,13 +518,12 @@ int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf) 
		(void) ip6_mc_del_src(idev, group, pmc->sfmode, 0, NULL, 0);

	pmc->sflist = newpsl;

	pmc->sfmode = gsf->gf_fmode;

	write_unlock_bh(&pmc->sflock);

	write_unlock(&pmc->sflock);

	err = 0;

done:

	read_unlock_bh(&ipv6_sk_mc_lock);

	read_unlock(&ipv6_sk_mc_lock);

	read_unlock_bh(&idev->lock);

	in6_dev_put(idev);

	dev_put(dev);

	rcu_read_unlock();

	if (leavegroup)

		err = ipv6_sock_mc_drop(sk, gsf->gf_interface, group);

	return err;
@@ -551,11 +546,13 @@ int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf, 
	if (!ipv6_addr_is_multicast(group))

		return -EINVAL;



	idev = ip6_mc_find_dev(net, group, gsf->gf_interface);

	rcu_read_lock();

	idev = ip6_mc_find_dev_rcu(net, group, gsf->gf_interface);



	if (!idev)

	if (!idev) {

		rcu_read_unlock();

		return -ENODEV;



	}

	dev = idev->dev;



	err = -EADDRNOTAVAIL;
@@ -577,8 +574,7 @@ int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf, 
	psl = pmc->sflist;

	count = psl ? psl->sl_count : 0;

	read_unlock_bh(&idev->lock);

	in6_dev_put(idev);

	dev_put(dev);

	rcu_read_unlock();



	copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;

	gsf->gf_numsrc = count;
@@ -604,8 +600,7 @@ int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf, 
	return 0;

done:

	read_unlock_bh(&idev->lock);

	in6_dev_put(idev);

	dev_put(dev);

	rcu_read_unlock();

	return err;

}
@@ -822,6 +817,7 @@ int ipv6_dev_mc_inc(struct net_device *dev, const struct in6_addr *addr) 
	struct ifmcaddr6 *mc;

	struct inet6_dev *idev;



	/* we need to take a reference on idev */

	idev = in6_dev_get(dev);



	if (idev == NULL)
@@ -860,7 +856,7 @@ int ipv6_dev_mc_inc(struct net_device *dev, const struct in6_addr *addr) 
	setup_timer(&mc->mca_timer, igmp6_timer_handler, (unsigned long)mc);



	ipv6_addr_copy(&mc->mca_addr, addr);

	mc->idev = idev;

	mc->idev = idev; /* (reference taken) */

	mc->mca_users = 1;

	/* mca_stamp should be updated upon changes */

	mc->mca_cstamp = mc->mca_tstamp = jiffies;
@@ -915,16 +911,18 @@ int __ipv6_dev_mc_dec(struct inet6_dev *idev, const struct in6_addr *addr) 


int ipv6_dev_mc_dec(struct net_device *dev, const struct in6_addr *addr)

{

	struct inet6_dev *idev = in6_dev_get(dev);

	struct inet6_dev *idev;

	int err;



	if (!idev)

		return -ENODEV;

	rcu_read_lock();



	idev = __in6_dev_get(dev);

	if (!idev)

		err = -ENODEV;

	else

		err = __ipv6_dev_mc_dec(idev, addr);



	in6_dev_put(idev);



	rcu_read_unlock();

	return err;

}
@@ -965,7 +963,8 @@ int ipv6_chk_mcast_addr(struct net_device *dev, const struct in6_addr *group, 
	struct ifmcaddr6 *mc;

	int rv = 0;



	idev = in6_dev_get(dev);

	rcu_read_lock();

	idev = __in6_dev_get(dev);

	if (idev) {

		read_lock_bh(&idev->lock);

		for (mc = idev->mc_list; mc; mc=mc->next) {
@@ -992,8 +991,8 @@ int ipv6_chk_mcast_addr(struct net_device *dev, const struct in6_addr *group, 
				rv = 1; /* don't filter unspecified source */

		}

		read_unlock_bh(&idev->lock);

		in6_dev_put(idev);

	}

	rcu_read_unlock();

	return rv;

}
@@ -1104,6 +1103,7 @@ static int mld_marksources(struct ifmcaddr6 *pmc, int nsrcs, 
	return 1;

}



/* called with rcu_read_lock() */

int igmp6_event_query(struct sk_buff *skb)

{

	struct mld2_query *mlh2 = NULL;
@@ -1127,7 +1127,7 @@ int igmp6_event_query(struct sk_buff *skb) 
	if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL))

		return -EINVAL;



	idev = in6_dev_get(skb->dev);

	idev = __in6_dev_get(skb->dev);



	if (idev == NULL)

		return 0;
@@ -1137,10 +1137,8 @@ int igmp6_event_query(struct sk_buff *skb) 
	group_type = ipv6_addr_type(group);



	if (group_type != IPV6_ADDR_ANY &&

	    !(group_type&IPV6_ADDR_MULTICAST)) {

		in6_dev_put(idev);

	    !(group_type&IPV6_ADDR_MULTICAST))

		return -EINVAL;

	}



	if (len == 24) {

		int switchback;
@@ -1161,10 +1159,9 @@ int igmp6_event_query(struct sk_buff *skb) 
	} else if (len >= 28) {

		int srcs_offset = sizeof(struct mld2_query) -

				  sizeof(struct icmp6hdr);

		if (!pskb_may_pull(skb, srcs_offset)) {

			in6_dev_put(idev);

		if (!pskb_may_pull(skb, srcs_offset))

			return -EINVAL;

		}



		mlh2 = (struct mld2_query *)skb_transport_header(skb);

		max_delay = (MLDV2_MRC(ntohs(mlh2->mld2q_mrc))*HZ)/1000;

		if (!max_delay)
@@ -1173,28 +1170,23 @@ int igmp6_event_query(struct sk_buff *skb) 
		if (mlh2->mld2q_qrv)

			idev->mc_qrv = mlh2->mld2q_qrv;

		if (group_type == IPV6_ADDR_ANY) { /* general query */

			if (mlh2->mld2q_nsrcs) {

				in6_dev_put(idev);

			if (mlh2->mld2q_nsrcs)

				return -EINVAL; /* no sources allowed */

			}



			mld_gq_start_timer(idev);

			in6_dev_put(idev);

			return 0;

		}

		/* mark sources to include, if group & source-specific */

		if (mlh2->mld2q_nsrcs != 0) {

			if (!pskb_may_pull(skb, srcs_offset +

			    ntohs(mlh2->mld2q_nsrcs) * sizeof(struct in6_addr))) {

				in6_dev_put(idev);

			    ntohs(mlh2->mld2q_nsrcs) * sizeof(struct in6_addr)))

				return -EINVAL;

			}



			mlh2 = (struct mld2_query *)skb_transport_header(skb);

			mark = 1;

		}

	} else {

		in6_dev_put(idev);

	} else

		return -EINVAL;

	}



	read_lock_bh(&idev->lock);

	if (group_type == IPV6_ADDR_ANY) {
@@ -1227,12 +1219,11 @@ int igmp6_event_query(struct sk_buff *skb) 
		}

	}

	read_unlock_bh(&idev->lock);

	in6_dev_put(idev);



	return 0;

}





/* called with rcu_read_lock() */

int igmp6_event_report(struct sk_buff *skb)

{

	struct ifmcaddr6 *ma;
@@ -1260,7 +1251,7 @@ int igmp6_event_report(struct sk_buff *skb) 
	    !(addr_type&IPV6_ADDR_LINKLOCAL))

		return -EINVAL;



	idev = in6_dev_get(skb->dev);

	idev = __in6_dev_get(skb->dev);

	if (idev == NULL)

		return -ENODEV;
@@ -1280,7 +1271,6 @@ int igmp6_event_report(struct sk_buff *skb) 
		}

	}

	read_unlock_bh(&idev->lock);

	in6_dev_put(idev);

	return 0;

}
@@ -1396,12 +1386,14 @@ static void mld_sendpack(struct sk_buff *skb) 
	struct mld2_report *pmr =

			      (struct mld2_report *)skb_transport_header(skb);

	int payload_len, mldlen;

	struct inet6_dev *idev = in6_dev_get(skb->dev);

	struct inet6_dev *idev;

	struct net *net = dev_net(skb->dev);

	int err;

	struct flowi fl;

	struct dst_entry *dst;



	rcu_read_lock();

	idev = __in6_dev_get(skb->dev);

	IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len);



	payload_len = (skb->tail - skb->network_header) - sizeof(*pip6);
@@ -1441,8 +1433,7 @@ out: 
	} else

		IP6_INC_STATS_BH(net, idev, IPSTATS_MIB_OUTDISCARDS);



	if (likely(idev != NULL))

		in6_dev_put(idev);

	rcu_read_unlock();

	return;



err_out:
@@ -1779,7 +1770,8 @@ static void igmp6_send(struct in6_addr *addr, struct net_device *dev, int type) 
					 IPPROTO_ICMPV6,

					 csum_partial(hdr, len, 0));



	idev = in6_dev_get(skb->dev);

	rcu_read_lock();

	idev = __in6_dev_get(skb->dev);



	dst = icmp6_dst_alloc(skb->dev, NULL, &ipv6_hdr(skb)->daddr);

	if (!dst) {
@@ -1806,8 +1798,7 @@ out: 
	} else

		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);



	if (likely(idev != NULL))

		in6_dev_put(idev);

	rcu_read_unlock();

	return;



err_out:

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