Commit 8571ab47 authored by Yuval Mintz's avatar Yuval Mintz Committed by David S. Miller
Browse files

ip6mr: Make mroute_sk rcu-based 



In ipmr the mr_table socket is handled under RCU. Introduce the same
for ip6mr.

Signed-off-by: default avatarYuval Mintz <yuvalm@mellanox.com>
Acked-by: default avatarNikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 6853f21f

include/linux/mroute6.h

+3 −3
Original line number Diff line number Diff line
@@ -111,12 +111,12 @@ extern int ip6mr_get_route(struct net *net, struct sk_buff *skb, 
			   struct rtmsg *rtm, u32 portid);



#ifdef CONFIG_IPV6_MROUTE

extern struct sock *mroute6_socket(struct net *net, struct sk_buff *skb);

bool mroute6_is_socket(struct net *net, struct sk_buff *skb);

extern int ip6mr_sk_done(struct sock *sk);

#else

static inline struct sock *mroute6_socket(struct net *net, struct sk_buff *skb)

static inline bool mroute6_is_socket(struct net *net, struct sk_buff *skb)

{

	return NULL;

	return false;

}

static inline int ip6mr_sk_done(struct sock *sk)

{

net/ipv6/ip6_output.c

+1 −1
Original line number Diff line number Diff line
@@ -71,7 +71,7 @@ static int ip6_finish_output2(struct net *net, struct sock *sk, struct sk_buff * 
		struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));



		if (!(dev->flags & IFF_LOOPBACK) && sk_mc_loop(sk) &&

		    ((mroute6_socket(net, skb) &&

		    ((mroute6_is_socket(net, skb) &&

		     !(IP6CB(skb)->flags & IP6SKB_FORWARDED)) ||

		     ipv6_chk_mcast_addr(dev, &ipv6_hdr(skb)->daddr,

					 &ipv6_hdr(skb)->saddr))) {

net/ipv6/ip6mr.c

+27 −18
Original line number Diff line number Diff line
@@ -58,7 +58,7 @@ struct mr6_table { 
	struct list_head	list;

	possible_net_t		net;

	u32			id;

	struct sock		*mroute6_sk;

	struct sock __rcu	*mroute6_sk;

	struct timer_list	ipmr_expire_timer;

	struct list_head	mfc6_unres_queue;

	struct list_head	mfc6_cache_array[MFC6_LINES];
@@ -1121,6 +1121,7 @@ static void ip6mr_cache_resolve(struct net *net, struct mr6_table *mrt, 
static int ip6mr_cache_report(struct mr6_table *mrt, struct sk_buff *pkt,

			      mifi_t mifi, int assert)

{

	struct sock *mroute6_sk;

	struct sk_buff *skb;

	struct mrt6msg *msg;

	int ret;
@@ -1190,17 +1191,19 @@ static int ip6mr_cache_report(struct mr6_table *mrt, struct sk_buff *pkt, 
	skb->ip_summed = CHECKSUM_UNNECESSARY;

	}



	if (!mrt->mroute6_sk) {

	rcu_read_lock();

	mroute6_sk = rcu_dereference(mrt->mroute6_sk);

	if (!mroute6_sk) {

		rcu_read_unlock();

		kfree_skb(skb);

		return -EINVAL;

	}



	mrt6msg_netlink_event(mrt, skb);



	/*

	 *	Deliver to user space multicast routing algorithms

	 */

	ret = sock_queue_rcv_skb(mrt->mroute6_sk, skb);

	/* Deliver to user space multicast routing algorithms */

	ret = sock_queue_rcv_skb(mroute6_sk, skb);

	rcu_read_unlock();

	if (ret < 0) {

		net_warn_ratelimited("mroute6: pending queue full, dropping entries\n");

		kfree_skb(skb);
@@ -1584,11 +1587,11 @@ static int ip6mr_sk_init(struct mr6_table *mrt, struct sock *sk) 


	rtnl_lock();

	write_lock_bh(&mrt_lock);

	if (likely(mrt->mroute6_sk == NULL)) {

		mrt->mroute6_sk = sk;

		net->ipv6.devconf_all->mc_forwarding++;

	} else {

	if (rtnl_dereference(mrt->mroute6_sk)) {

		err = -EADDRINUSE;

	} else {

		rcu_assign_pointer(mrt->mroute6_sk, sk);

		net->ipv6.devconf_all->mc_forwarding++;

	}

	write_unlock_bh(&mrt_lock);
@@ -1614,9 +1617,9 @@ int ip6mr_sk_done(struct sock *sk) 


	rtnl_lock();

	ip6mr_for_each_table(mrt, net) {

		if (sk == mrt->mroute6_sk) {

		if (sk == rtnl_dereference(mrt->mroute6_sk)) {

			write_lock_bh(&mrt_lock);

			mrt->mroute6_sk = NULL;

			RCU_INIT_POINTER(mrt->mroute6_sk, NULL);

			net->ipv6.devconf_all->mc_forwarding--;

			write_unlock_bh(&mrt_lock);

			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
@@ -1630,11 +1633,12 @@ int ip6mr_sk_done(struct sock *sk) 
		}

	}

	rtnl_unlock();

	synchronize_rcu();



	return err;

}



struct sock *mroute6_socket(struct net *net, struct sk_buff *skb)

bool mroute6_is_socket(struct net *net, struct sk_buff *skb)

{

	struct mr6_table *mrt;

	struct flowi6 fl6 = {
@@ -1646,8 +1650,9 @@ struct sock *mroute6_socket(struct net *net, struct sk_buff *skb) 
	if (ip6mr_fib_lookup(net, &fl6, &mrt) < 0)

		return NULL;



	return mrt->mroute6_sk;

	return rcu_access_pointer(mrt->mroute6_sk);

}

EXPORT_SYMBOL(mroute6_is_socket);



/*

 *	Socket options and virtual interface manipulation. The whole
@@ -1674,7 +1679,8 @@ int ip6_mroute_setsockopt(struct sock *sk, int optname, char __user *optval, uns 
		return -ENOENT;



	if (optname != MRT6_INIT) {

		if (sk != mrt->mroute6_sk && !ns_capable(net->user_ns, CAP_NET_ADMIN))

		if (sk != rcu_access_pointer(mrt->mroute6_sk) &&

		    !ns_capable(net->user_ns, CAP_NET_ADMIN))

			return -EACCES;

	}
@@ -1696,7 +1702,8 @@ int ip6_mroute_setsockopt(struct sock *sk, int optname, char __user *optval, uns 
		if (vif.mif6c_mifi >= MAXMIFS)

			return -ENFILE;

		rtnl_lock();

		ret = mif6_add(net, mrt, &vif, sk == mrt->mroute6_sk);

		ret = mif6_add(net, mrt, &vif,

			       sk == rtnl_dereference(mrt->mroute6_sk));

		rtnl_unlock();

		return ret;
@@ -1731,7 +1738,9 @@ int ip6_mroute_setsockopt(struct sock *sk, int optname, char __user *optval, uns 
			ret = ip6mr_mfc_delete(mrt, &mfc, parent);

		else

			ret = ip6mr_mfc_add(net, mrt, &mfc,

					    sk == mrt->mroute6_sk, parent);

					    sk ==

					    rtnl_dereference(mrt->mroute6_sk),

					    parent);

		rtnl_unlock();

		return ret;
@@ -1783,7 +1792,7 @@ int ip6_mroute_setsockopt(struct sock *sk, int optname, char __user *optval, uns 
		/* "pim6reg%u" should not exceed 16 bytes (IFNAMSIZ) */

		if (v != RT_TABLE_DEFAULT && v >= 100000000)

			return -EINVAL;

		if (sk == mrt->mroute6_sk)

		if (sk == rcu_access_pointer(mrt->mroute6_sk))

			return -EBUSY;



		rtnl_lock();