Commit e0b26cc9 authored by Julian Anastasov's avatar Julian Anastasov Committed by Simon Horman
Browse files

ipvs: call rtnl_lock early 



When the sync damon is started we need to hold rtnl
lock while calling ip_mc_join_group. Currently, we have
a wrong locking order because the correct one is
rtnl_lock->__ip_vs_mutex. It is implied from the usage
of __ip_vs_mutex in ip_vs_dst_event() which is called
under rtnl lock during NETDEV_* notifications.

Fix the problem by calling rtnl_lock early only for the
start_sync_thread call. As a bonus this fixes the usage
__dev_get_by_name which was not called under rtnl lock.

This patch actually extends and depends on commit 54ff9ef3
("ipv4, ipv6: kill ip_mc_{join, leave}_group and
ipv6_sock_mc_{join, drop}").

Signed-off-by: default avatarJulian Anastasov <ja@ssi.bg>
Signed-off-by: default avatarSimon Horman <horms@verge.net.au>
parent eefa32d3

net/netfilter/ipvs/ip_vs_ctl.c

+33 −17
Original line number Diff line number Diff line
@@ -2335,13 +2335,18 @@ do_ip_vs_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len) 
	    cmd == IP_VS_SO_SET_STOPDAEMON) {

		struct ip_vs_daemon_user *dm = (struct ip_vs_daemon_user *)arg;



		if (cmd == IP_VS_SO_SET_STARTDAEMON) {

			rtnl_lock();

			mutex_lock(&ipvs->sync_mutex);

		if (cmd == IP_VS_SO_SET_STARTDAEMON)

			ret = start_sync_thread(net, dm->state, dm->mcast_ifn,

						dm->syncid);

		else

			mutex_unlock(&ipvs->sync_mutex);

			rtnl_unlock();

		} else {

			mutex_lock(&ipvs->sync_mutex);

			ret = stop_sync_thread(net, dm->state);

			mutex_unlock(&ipvs->sync_mutex);

		}

		goto out_dec;

	}
@@ -3342,6 +3347,9 @@ nla_put_failure: 


static int ip_vs_genl_new_daemon(struct net *net, struct nlattr **attrs)

{

	struct netns_ipvs *ipvs = net_ipvs(net);

	int ret;



	if (!(attrs[IPVS_DAEMON_ATTR_STATE] &&

	      attrs[IPVS_DAEMON_ATTR_MCAST_IFN] &&

	      attrs[IPVS_DAEMON_ATTR_SYNC_ID]))
@@ -3353,19 +3361,30 @@ static int ip_vs_genl_new_daemon(struct net *net, struct nlattr **attrs) 
	if (net_ipvs(net)->mixed_address_family_dests > 0)

		return -EINVAL;



	return start_sync_thread(net,

	rtnl_lock();

	mutex_lock(&ipvs->sync_mutex);

	ret = start_sync_thread(net,

				nla_get_u32(attrs[IPVS_DAEMON_ATTR_STATE]),

				nla_data(attrs[IPVS_DAEMON_ATTR_MCAST_IFN]),

				nla_get_u32(attrs[IPVS_DAEMON_ATTR_SYNC_ID]));

	mutex_unlock(&ipvs->sync_mutex);

	rtnl_unlock();

	return ret;

}



static int ip_vs_genl_del_daemon(struct net *net, struct nlattr **attrs)

{

	struct netns_ipvs *ipvs = net_ipvs(net);

	int ret;



	if (!attrs[IPVS_DAEMON_ATTR_STATE])

		return -EINVAL;



	return stop_sync_thread(net,

	mutex_lock(&ipvs->sync_mutex);

	ret = stop_sync_thread(net,

			       nla_get_u32(attrs[IPVS_DAEMON_ATTR_STATE]));

	mutex_unlock(&ipvs->sync_mutex);

	return ret;

}



static int ip_vs_genl_set_config(struct net *net, struct nlattr **attrs)
@@ -3389,7 +3408,7 @@ static int ip_vs_genl_set_config(struct net *net, struct nlattr **attrs) 


static int ip_vs_genl_set_daemon(struct sk_buff *skb, struct genl_info *info)

{

	int ret = 0, cmd;

	int ret = -EINVAL, cmd;

	struct net *net;

	struct netns_ipvs *ipvs;
@@ -3400,22 +3419,19 @@ static int ip_vs_genl_set_daemon(struct sk_buff *skb, struct genl_info *info) 
	if (cmd == IPVS_CMD_NEW_DAEMON || cmd == IPVS_CMD_DEL_DAEMON) {

		struct nlattr *daemon_attrs[IPVS_DAEMON_ATTR_MAX + 1];



		mutex_lock(&ipvs->sync_mutex);

		if (!info->attrs[IPVS_CMD_ATTR_DAEMON] ||

		    nla_parse_nested(daemon_attrs, IPVS_DAEMON_ATTR_MAX,

				     info->attrs[IPVS_CMD_ATTR_DAEMON],

				     ip_vs_daemon_policy)) {

			ret = -EINVAL;

				     ip_vs_daemon_policy))

			goto out;

		}



		if (cmd == IPVS_CMD_NEW_DAEMON)

			ret = ip_vs_genl_new_daemon(net, daemon_attrs);

		else

			ret = ip_vs_genl_del_daemon(net, daemon_attrs);

out:

		mutex_unlock(&ipvs->sync_mutex);

	}



out:

	return ret;

}

net/netfilter/ipvs/ip_vs_sync.c

+0 −2
Original line number Diff line number Diff line
@@ -1405,11 +1405,9 @@ join_mcast_group(struct sock *sk, struct in_addr *addr, char *ifname) 


	mreq.imr_ifindex = dev->ifindex;



	rtnl_lock();

	lock_sock(sk);

	ret = ip_mc_join_group(sk, &mreq);

	release_sock(sk);

	rtnl_unlock();



	return ret;

}

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