Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next

Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

This a bit large (and late) patchset that contains Netfilter updates for
net-next. Most relevantly br_netfilter fixes, ipset RCU support, removal of
x_tables percpu ruleset copy and rework of the nf_tables netdev support. More
specifically, they are:

1) Warn the user when there is a better protocol conntracker available, from
   Marcelo Ricardo Leitner.

2) Fix forwarding of IPv6 fragmented traffic in br_netfilter, from Bernhard
   Thaler. This comes with several patches to prepare the change in first place.

3) Get rid of special mtu handling of PPPoE/VLAN frames for br_netfilter. This
   is not needed anymore since now we use the largest fragment size to
   refragment, from Florian Westphal.

4) Restore vlan tag when refragmenting in br_netfilter, also from Florian.

5) Get rid of the percpu ruleset copy in x_tables, from Florian. Plus another
   follow up patch to refine it from Eric Dumazet.

6) Several ipset cleanups, fixes and finally RCU support, from Jozsef Kadlecsik.

7) Get rid of parens in Netfilter Kconfig files.

8) Attach the net_device to the basechain as opposed to the initial per table
   approach in the nf_tables netdev family.

9) Subscribe to netdev events to detect the removal and registration of a
   device that is referenced by a basechain.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 184 insertions, 160 deletions

diff --git a/net/netfilter/ipset/ip_set_core.c b/net/netfilter/ipset/ip_set_core.c
index 475e496..338b404 100644
--- a/net/netfilter/ipset/ip_set_core.c
+++ b/net/netfilter/ipset/ip_set_core.c
@@ -32,8 +32,10 @@ static DEFINE_RWLOCK(ip_set_ref_lock);		/* protects the set refs */
 struct ip_set_net {
 	struct ip_set * __rcu *ip_set_list;	/* all individual sets */
 	ip_set_id_t	ip_set_max;	/* max number of sets */
-	int		is_deleted;	/* deleted by ip_set_net_exit */
+	bool		is_deleted;	/* deleted by ip_set_net_exit */
+	bool		is_destroyed;	/* all sets are destroyed */
 };
+
 static int ip_set_net_id __read_mostly;
 
 static inline struct ip_set_net *ip_set_pernet(struct net *net)
@@ -59,8 +61,7 @@ MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_IPSET);
 #define ip_set(inst, id)		\
 	ip_set_dereference((inst)->ip_set_list)[id]
 
-/*
- * The set types are implemented in modules and registered set types
+/* The set types are implemented in modules and registered set types
  * can be found in ip_set_type_list. Adding/deleting types is
  * serialized by ip_set_type_mutex.
  */
@@ -130,7 +131,8 @@ __find_set_type_get(const char *name, u8 family, u8 revision,
 		goto unlock;
 	}
 	/* Make sure the type is already loaded
-	 * but we don't support the revision */
+	 * but we don't support the revision
+	 */
 	list_for_each_entry_rcu(type, &ip_set_type_list, list)
 		if (STRNCMP(type->name, name)) {
 			err = -IPSET_ERR_FIND_TYPE;
@@ -208,15 +210,15 @@ ip_set_type_register(struct ip_set_type *type)
 		pr_warn("ip_set type %s, family %s with revision min %u already registered!\n",
 			type->name, family_name(type->family),
 			type->revision_min);
-		ret = -EINVAL;
-		goto unlock;
+		ip_set_type_unlock();
+		return -EINVAL;
 	}
 	list_add_rcu(&type->list, &ip_set_type_list);
 	pr_debug("type %s, family %s, revision %u:%u registered.\n",
 		 type->name, family_name(type->family),
 		 type->revision_min, type->revision_max);
-unlock:
 	ip_set_type_unlock();
+
 	return ret;
 }
 EXPORT_SYMBOL_GPL(ip_set_type_register);
@@ -230,12 +232,12 @@ ip_set_type_unregister(struct ip_set_type *type)
 		pr_warn("ip_set type %s, family %s with revision min %u not registered\n",
 			type->name, family_name(type->family),
 			type->revision_min);
-		goto unlock;
+		ip_set_type_unlock();
+		return;
 	}
 	list_del_rcu(&type->list);
 	pr_debug("type %s, family %s with revision min %u unregistered.\n",
 		 type->name, family_name(type->family), type->revision_min);
-unlock:
 	ip_set_type_unlock();
 
 	synchronize_rcu();
@@ -289,7 +291,7 @@ static const struct nla_policy ipaddr_policy[IPSET_ATTR_IPADDR_MAX + 1] = {
 int
 ip_set_get_ipaddr4(struct nlattr *nla,  __be32 *ipaddr)
 {
-	struct nlattr *tb[IPSET_ATTR_IPADDR_MAX+1];
+	struct nlattr *tb[IPSET_ATTR_IPADDR_MAX + 1];
 
 	if (unlikely(!flag_nested(nla)))
 		return -IPSET_ERR_PROTOCOL;
@@ -306,7 +308,7 @@ EXPORT_SYMBOL_GPL(ip_set_get_ipaddr4);
 int
 ip_set_get_ipaddr6(struct nlattr *nla, union nf_inet_addr *ipaddr)
 {
-	struct nlattr *tb[IPSET_ATTR_IPADDR_MAX+1];
+	struct nlattr *tb[IPSET_ATTR_IPADDR_MAX + 1];
 
 	if (unlikely(!flag_nested(nla)))
 		return -IPSET_ERR_PROTOCOL;
@@ -317,7 +319,7 @@ ip_set_get_ipaddr6(struct nlattr *nla, union nf_inet_addr *ipaddr)
 		return -IPSET_ERR_PROTOCOL;
 
 	memcpy(ipaddr, nla_data(tb[IPSET_ATTR_IPADDR_IPV6]),
-		sizeof(struct in6_addr));
+	       sizeof(struct in6_addr));
 	return 0;
 }
 EXPORT_SYMBOL_GPL(ip_set_get_ipaddr6);
@@ -389,13 +391,22 @@ ip_set_get_extensions(struct ip_set *set, struct nlattr *tb[],
 		      struct ip_set_ext *ext)
 {
 	u64 fullmark;
+
+	if (unlikely(!ip_set_optattr_netorder(tb, IPSET_ATTR_TIMEOUT) ||
+		     !ip_set_optattr_netorder(tb, IPSET_ATTR_PACKETS) ||
+		     !ip_set_optattr_netorder(tb, IPSET_ATTR_BYTES) ||
+		     !ip_set_optattr_netorder(tb, IPSET_ATTR_SKBMARK) ||
+		     !ip_set_optattr_netorder(tb, IPSET_ATTR_SKBPRIO) ||
+		     !ip_set_optattr_netorder(tb, IPSET_ATTR_SKBQUEUE)))
+		return -IPSET_ERR_PROTOCOL;
+
 	if (tb[IPSET_ATTR_TIMEOUT]) {
-		if (!(set->extensions & IPSET_EXT_TIMEOUT))
+		if (!SET_WITH_TIMEOUT(set))
 			return -IPSET_ERR_TIMEOUT;
 		ext->timeout = ip_set_timeout_uget(tb[IPSET_ATTR_TIMEOUT]);
 	}
 	if (tb[IPSET_ATTR_BYTES] || tb[IPSET_ATTR_PACKETS]) {
-		if (!(set->extensions & IPSET_EXT_COUNTER))
+		if (!SET_WITH_COUNTER(set))
 			return -IPSET_ERR_COUNTER;
 		if (tb[IPSET_ATTR_BYTES])
 			ext->bytes = be64_to_cpu(nla_get_be64(
@@ -405,25 +416,25 @@ ip_set_get_extensions(struct ip_set *set, struct nlattr *tb[],
 						   tb[IPSET_ATTR_PACKETS]));
 	}
 	if (tb[IPSET_ATTR_COMMENT]) {
-		if (!(set->extensions & IPSET_EXT_COMMENT))
+		if (!SET_WITH_COMMENT(set))
 			return -IPSET_ERR_COMMENT;
 		ext->comment = ip_set_comment_uget(tb[IPSET_ATTR_COMMENT]);
 	}
 	if (tb[IPSET_ATTR_SKBMARK]) {
-		if (!(set->extensions & IPSET_EXT_SKBINFO))
+		if (!SET_WITH_SKBINFO(set))
 			return -IPSET_ERR_SKBINFO;
 		fullmark = be64_to_cpu(nla_get_be64(tb[IPSET_ATTR_SKBMARK]));
 		ext->skbmark = fullmark >> 32;
 		ext->skbmarkmask = fullmark & 0xffffffff;
 	}
 	if (tb[IPSET_ATTR_SKBPRIO]) {
-		if (!(set->extensions & IPSET_EXT_SKBINFO))
+		if (!SET_WITH_SKBINFO(set))
 			return -IPSET_ERR_SKBINFO;
 		ext->skbprio = be32_to_cpu(nla_get_be32(
 					    tb[IPSET_ATTR_SKBPRIO]));
 	}
 	if (tb[IPSET_ATTR_SKBQUEUE]) {
-		if (!(set->extensions & IPSET_EXT_SKBINFO))
+		if (!SET_WITH_SKBINFO(set))
 			return -IPSET_ERR_SKBINFO;
 		ext->skbqueue = be16_to_cpu(nla_get_be16(
 					    tb[IPSET_ATTR_SKBQUEUE]));
@@ -457,8 +468,7 @@ ip_set_put_extensions(struct sk_buff *skb, const struct ip_set *set,
 }
 EXPORT_SYMBOL_GPL(ip_set_put_extensions);
 
-/*
- * Creating/destroying/renaming/swapping affect the existence and
+/* Creating/destroying/renaming/swapping affect the existence and
  * the properties of a set. All of these can be executed from userspace
  * only and serialized by the nfnl mutex indirectly from nfnetlink.
  *
@@ -485,8 +495,7 @@ __ip_set_put(struct ip_set *set)
 	write_unlock_bh(&ip_set_ref_lock);
 }
 
-/*
- * Add, del and test set entries from kernel.
+/* Add, del and test set entries from kernel.
  *
  * The set behind the index must exist and must be referenced
  * so it can't be destroyed (or changed) under our foot.
@@ -514,23 +523,23 @@ ip_set_test(ip_set_id_t index, const struct sk_buff *skb,
 			dev_net(par->in ? par->in : par->out), index);
 	int ret = 0;
 
-	BUG_ON(set == NULL);
+	BUG_ON(!set);
 	pr_debug("set %s, index %u\n", set->name, index);
 
 	if (opt->dim < set->type->dimension ||
 	    !(opt->family == set->family || set->family == NFPROTO_UNSPEC))
 		return 0;
 
-	read_lock_bh(&set->lock);
+	rcu_read_lock_bh();
 	ret = set->variant->kadt(set, skb, par, IPSET_TEST, opt);
-	read_unlock_bh(&set->lock);
+	rcu_read_unlock_bh();
 
 	if (ret == -EAGAIN) {
 		/* Type requests element to be completed */
 		pr_debug("element must be completed, ADD is triggered\n");
-		write_lock_bh(&set->lock);
+		spin_lock_bh(&set->lock);
 		set->variant->kadt(set, skb, par, IPSET_ADD, opt);
-		write_unlock_bh(&set->lock);
+		spin_unlock_bh(&set->lock);
 		ret = 1;
 	} else {
 		/* --return-nomatch: invert matched element */
@@ -553,16 +562,16 @@ ip_set_add(ip_set_id_t index, const struct sk_buff *skb,
 			dev_net(par->in ? par->in : par->out), index);
 	int ret;
 
-	BUG_ON(set == NULL);
+	BUG_ON(!set);
 	pr_debug("set %s, index %u\n", set->name, index);
 
 	if (opt->dim < set->type->dimension ||
 	    !(opt->family == set->family || set->family == NFPROTO_UNSPEC))
 		return -IPSET_ERR_TYPE_MISMATCH;
 
-	write_lock_bh(&set->lock);
+	spin_lock_bh(&set->lock);
 	ret = set->variant->kadt(set, skb, par, IPSET_ADD, opt);
-	write_unlock_bh(&set->lock);
+	spin_unlock_bh(&set->lock);
 
 	return ret;
 }
@@ -576,23 +585,22 @@ ip_set_del(ip_set_id_t index, const struct sk_buff *skb,
 			dev_net(par->in ? par->in : par->out), index);
 	int ret = 0;
 
-	BUG_ON(set == NULL);
+	BUG_ON(!set);
 	pr_debug("set %s, index %u\n", set->name, index);
 
 	if (opt->dim < set->type->dimension ||
 	    !(opt->family == set->family || set->family == NFPROTO_UNSPEC))
 		return -IPSET_ERR_TYPE_MISMATCH;
 
-	write_lock_bh(&set->lock);
+	spin_lock_bh(&set->lock);
 	ret = set->variant->kadt(set, skb, par, IPSET_DEL, opt);
-	write_unlock_bh(&set->lock);
+	spin_unlock_bh(&set->lock);
 
 	return ret;
 }
 EXPORT_SYMBOL_GPL(ip_set_del);
 
-/*
- * Find set by name, reference it once. The reference makes sure the
+/* Find set by name, reference it once. The reference makes sure the
  * thing pointed to, does not go away under our feet.
  *
  */
@@ -606,7 +614,7 @@ ip_set_get_byname(struct net *net, const char *name, struct ip_set **set)
 	rcu_read_lock();
 	for (i = 0; i < inst->ip_set_max; i++) {
 		s = rcu_dereference(inst->ip_set_list)[i];
-		if (s != NULL && STRNCMP(s->name, name)) {
+		if (s && STRNCMP(s->name, name)) {
 			__ip_set_get(s);
 			index = i;
 			*set = s;
@@ -619,8 +627,7 @@ ip_set_get_byname(struct net *net, const char *name, struct ip_set **set)
 }
 EXPORT_SYMBOL_GPL(ip_set_get_byname);
 
-/*
- * If the given set pointer points to a valid set, decrement
+/* If the given set pointer points to a valid set, decrement
  * reference count by 1. The caller shall not assume the index
  * to be valid, after calling this function.
  *
@@ -633,7 +640,7 @@ __ip_set_put_byindex(struct ip_set_net *inst, ip_set_id_t index)
 
 	rcu_read_lock();
 	set = rcu_dereference(inst->ip_set_list)[index];
-	if (set != NULL)
+	if (set)
 		__ip_set_put(set);
 	rcu_read_unlock();
 }
@@ -647,8 +654,7 @@ ip_set_put_byindex(struct net *net, ip_set_id_t index)
 }
 EXPORT_SYMBOL_GPL(ip_set_put_byindex);
 
-/*
- * Get the name of a set behind a set index.
+/* Get the name of a set behind a set index.
  * We assume the set is referenced, so it does exist and
  * can't be destroyed. The set cannot be renamed due to
  * the referencing either.
@@ -659,7 +665,7 @@ ip_set_name_byindex(struct net *net, ip_set_id_t index)
 {
 	const struct ip_set *set = ip_set_rcu_get(net, index);
 
-	BUG_ON(set == NULL);
+	BUG_ON(!set);
 	BUG_ON(set->ref == 0);
 
 	/* Referenced, so it's safe */
@@ -667,13 +673,11 @@ ip_set_name_byindex(struct net *net, ip_set_id_t index)
 }
 EXPORT_SYMBOL_GPL(ip_set_name_byindex);
 
-/*
- * Routines to call by external subsystems, which do not
+/* Routines to call by external subsystems, which do not
  * call nfnl_lock for us.
  */
 
-/*
- * Find set by index, reference it once. The reference makes sure the
+/* Find set by index, reference it once. The reference makes sure the
  * thing pointed to, does not go away under our feet.
  *
  * The nfnl mutex is used in the function.
@@ -699,8 +703,7 @@ ip_set_nfnl_get_byindex(struct net *net, ip_set_id_t index)
 }
 EXPORT_SYMBOL_GPL(ip_set_nfnl_get_byindex);
 
-/*
- * If the given set pointer points to a valid set, decrement
+/* If the given set pointer points to a valid set, decrement
  * reference count by 1. The caller shall not assume the index
  * to be valid, after calling this function.
  *
@@ -715,15 +718,14 @@ ip_set_nfnl_put(struct net *net, ip_set_id_t index)
 	nfnl_lock(NFNL_SUBSYS_IPSET);
 	if (!inst->is_deleted) { /* already deleted from ip_set_net_exit() */
 		set = ip_set(inst, index);
-		if (set != NULL)
+		if (set)
 			__ip_set_put(set);
 	}
 	nfnl_unlock(NFNL_SUBSYS_IPSET);
 }
 EXPORT_SYMBOL_GPL(ip_set_nfnl_put);
 
-/*
- * Communication protocol with userspace over netlink.
+/* Communication protocol with userspace over netlink.
  *
  * The commands are serialized by the nfnl mutex.
  */
@@ -750,7 +752,7 @@ start_msg(struct sk_buff *skb, u32 portid, u32 seq, unsigned int flags,
 
 	nlh = nlmsg_put(skb, portid, seq, cmd | (NFNL_SUBSYS_IPSET << 8),
 			sizeof(*nfmsg), flags);
-	if (nlh == NULL)
+	if (!nlh)
 		return NULL;
 
 	nfmsg = nlmsg_data(nlh);
@@ -783,7 +785,7 @@ find_set_and_id(struct ip_set_net *inst, const char *name, ip_set_id_t *id)
 	*id = IPSET_INVALID_ID;
 	for (i = 0; i < inst->ip_set_max; i++) {
 		set = ip_set(inst, i);
-		if (set != NULL && STRNCMP(set->name, name)) {
+		if (set && STRNCMP(set->name, name)) {
 			*id = i;
 			break;
 		}
@@ -809,7 +811,7 @@ find_free_id(struct ip_set_net *inst, const char *name, ip_set_id_t *index,
 	*index = IPSET_INVALID_ID;
 	for (i = 0;  i < inst->ip_set_max; i++) {
 		s = ip_set(inst, i);
-		if (s == NULL) {
+		if (!s) {
 			if (*index == IPSET_INVALID_ID)
 				*index = i;
 		} else if (STRNCMP(name, s->name)) {
@@ -841,18 +843,18 @@ ip_set_create(struct sock *ctnl, struct sk_buff *skb,
 	struct ip_set_net *inst = ip_set_pernet(net);
 	struct ip_set *set, *clash = NULL;
 	ip_set_id_t index = IPSET_INVALID_ID;
-	struct nlattr *tb[IPSET_ATTR_CREATE_MAX+1] = {};
+	struct nlattr *tb[IPSET_ATTR_CREATE_MAX + 1] = {};
 	const char *name, *typename;
 	u8 family, revision;
 	u32 flags = flag_exist(nlh);
 	int ret = 0;
 
 	if (unlikely(protocol_failed(attr) ||
-		     attr[IPSET_ATTR_SETNAME] == NULL ||
-		     attr[IPSET_ATTR_TYPENAME] == NULL ||
-		     attr[IPSET_ATTR_REVISION] == NULL ||
-		     attr[IPSET_ATTR_FAMILY] == NULL ||
-		     (attr[IPSET_ATTR_DATA] != NULL &&
+		     !attr[IPSET_ATTR_SETNAME] ||
+		     !attr[IPSET_ATTR_TYPENAME] ||
+		     !attr[IPSET_ATTR_REVISION] ||
+		     !attr[IPSET_ATTR_FAMILY] ||
+		     (attr[IPSET_ATTR_DATA] &&
 		      !flag_nested(attr[IPSET_ATTR_DATA]))))
 		return -IPSET_ERR_PROTOCOL;
 
@@ -863,33 +865,29 @@ ip_set_create(struct sock *ctnl, struct sk_buff *skb,
 	pr_debug("setname: %s, typename: %s, family: %s, revision: %u\n",
 		 name, typename, family_name(family), revision);
 
-	/*
-	 * First, and without any locks, allocate and initialize
+	/* First, and without any locks, allocate and initialize
 	 * a normal base set structure.
 	 */
-	set = kzalloc(sizeof(struct ip_set), GFP_KERNEL);
+	set = kzalloc(sizeof(*set), GFP_KERNEL);
 	if (!set)
 		return -ENOMEM;
-	rwlock_init(&set->lock);
+	spin_lock_init(&set->lock);
 	strlcpy(set->name, name, IPSET_MAXNAMELEN);
 	set->family = family;
 	set->revision = revision;
 
-	/*
-	 * Next, check that we know the type, and take
+	/* Next, check that we know the type, and take
 	 * a reference on the type, to make sure it stays available
 	 * while constructing our new set.
 	 *
 	 * After referencing the type, we try to create the type
 	 * specific part of the set without holding any locks.
 	 */
-	ret = find_set_type_get(typename, family, revision, &(set->type));
+	ret = find_set_type_get(typename, family, revision, &set->type);
 	if (ret)
 		goto out;
 
-	/*
-	 * Without holding any locks, create private part.
-	 */
+	/* Without holding any locks, create private part. */
 	if (attr[IPSET_ATTR_DATA] &&
 	    nla_parse_nested(tb, IPSET_ATTR_CREATE_MAX, attr[IPSET_ATTR_DATA],
 			     set->type->create_policy)) {
@@ -903,8 +901,7 @@ ip_set_create(struct sock *ctnl, struct sk_buff *skb,
 
 	/* BTW, ret==0 here. */
 
-	/*
-	 * Here, we have a valid, constructed set and we are protected
+	/* Here, we have a valid, constructed set and we are protected
 	 * by the nfnl mutex. Find the first free index in ip_set_list
 	 * and check clashing.
 	 */
@@ -927,7 +924,7 @@ ip_set_create(struct sock *ctnl, struct sk_buff *skb,
 			/* Wraparound */
 			goto cleanup;
 
-		list = kzalloc(sizeof(struct ip_set *) * i, GFP_KERNEL);
+		list = kcalloc(i, sizeof(struct ip_set *), GFP_KERNEL);
 		if (!list)
 			goto cleanup;
 		/* nfnl mutex is held, both lists are valid */
@@ -941,12 +938,11 @@ ip_set_create(struct sock *ctnl, struct sk_buff *skb,
 		inst->ip_set_max = i;
 		kfree(tmp);
 		ret = 0;
-	} else if (ret)
+	} else if (ret) {
 		goto cleanup;
+	}
 
-	/*
-	 * Finally! Add our shiny new set to the list, and be done.
-	 */
+	/* Finally! Add our shiny new set to the list, and be done. */
 	pr_debug("create: '%s' created with index %u!\n", set->name, index);
 	ip_set(inst, index) = set;
 
@@ -971,12 +967,9 @@ ip_set_setname_policy[IPSET_ATTR_CMD_MAX + 1] = {
 };
 
 static void
-ip_set_destroy_set(struct ip_set_net *inst, ip_set_id_t index)
+ip_set_destroy_set(struct ip_set *set)
 {
-	struct ip_set *set = ip_set(inst, index);
-
 	pr_debug("set: %s\n",  set->name);
-	ip_set(inst, index) = NULL;
 
 	/* Must call it without holding any lock */
 	set->variant->destroy(set);
@@ -1011,30 +1004,36 @@ ip_set_destroy(struct sock *ctnl, struct sk_buff *skb,
 	if (!attr[IPSET_ATTR_SETNAME]) {
 		for (i = 0; i < inst->ip_set_max; i++) {
 			s = ip_set(inst, i);
-			if (s != NULL && s->ref) {
+			if (s && s->ref) {
 				ret = -IPSET_ERR_BUSY;
 				goto out;
 			}
 		}
+		inst->is_destroyed = true;
 		read_unlock_bh(&ip_set_ref_lock);
 		for (i = 0; i < inst->ip_set_max; i++) {
 			s = ip_set(inst, i);
-			if (s != NULL)
-				ip_set_destroy_set(inst, i);
+			if (s) {
+				ip_set(inst, i) = NULL;
+				ip_set_destroy_set(s);
+			}
 		}
+		/* Modified by ip_set_destroy() only, which is serialized */
+		inst->is_destroyed = false;
 	} else {
 		s = find_set_and_id(inst, nla_data(attr[IPSET_ATTR_SETNAME]),
 				    &i);
-		if (s == NULL) {
+		if (!s) {
 			ret = -ENOENT;
 			goto out;
 		} else if (s->ref) {
 			ret = -IPSET_ERR_BUSY;
 			goto out;
 		}
+		ip_set(inst, i) = NULL;
 		read_unlock_bh(&ip_set_ref_lock);
 
-		ip_set_destroy_set(inst, i);
+		ip_set_destroy_set(s);
 	}
 	return 0;
 out:
@@ -1049,9 +1048,9 @@ ip_set_flush_set(struct ip_set *set)
 {
 	pr_debug("set: %s\n",  set->name);
 
-	write_lock_bh(&set->lock);
+	spin_lock_bh(&set->lock);
 	set->variant->flush(set);
-	write_unlock_bh(&set->lock);
+	spin_unlock_bh(&set->lock);
 }
 
 static int
@@ -1069,12 +1068,12 @@ ip_set_flush(struct sock *ctnl, struct sk_buff *skb,
 	if (!attr[IPSET_ATTR_SETNAME]) {
 		for (i = 0; i < inst->ip_set_max; i++) {
 			s = ip_set(inst, i);
-			if (s != NULL)
+			if (s)
 				ip_set_flush_set(s);
 		}
 	} else {
 		s = find_set(inst, nla_data(attr[IPSET_ATTR_SETNAME]));
-		if (s == NULL)
+		if (!s)
 			return -ENOENT;
 
 		ip_set_flush_set(s);
@@ -1106,12 +1105,12 @@ ip_set_rename(struct sock *ctnl, struct sk_buff *skb,
 	int ret = 0;
 
 	if (unlikely(protocol_failed(attr) ||
-		     attr[IPSET_ATTR_SETNAME] == NULL ||
-		     attr[IPSET_ATTR_SETNAME2] == NULL))
+		     !attr[IPSET_ATTR_SETNAME] ||
+		     !attr[IPSET_ATTR_SETNAME2]))
 		return -IPSET_ERR_PROTOCOL;
 
 	set = find_set(inst, nla_data(attr[IPSET_ATTR_SETNAME]));
-	if (set == NULL)
+	if (!set)
 		return -ENOENT;
 
 	read_lock_bh(&ip_set_ref_lock);
@@ -1123,7 +1122,7 @@ ip_set_rename(struct sock *ctnl, struct sk_buff *skb,
 	name2 = nla_data(attr[IPSET_ATTR_SETNAME2]);
 	for (i = 0; i < inst->ip_set_max; i++) {
 		s = ip_set(inst, i);
-		if (s != NULL && STRNCMP(s->name, name2)) {
+		if (s && STRNCMP(s->name, name2)) {
 			ret = -IPSET_ERR_EXIST_SETNAME2;
 			goto out;
 		}
@@ -1155,23 +1154,24 @@ ip_set_swap(struct sock *ctnl, struct sk_buff *skb,
 	char from_name[IPSET_MAXNAMELEN];
 
 	if (unlikely(protocol_failed(attr) ||
-		     attr[IPSET_ATTR_SETNAME] == NULL ||
-		     attr[IPSET_ATTR_SETNAME2] == NULL))
+		     !attr[IPSET_ATTR_SETNAME] ||
+		     !attr[IPSET_ATTR_SETNAME2]))
 		return -IPSET_ERR_PROTOCOL;
 
 	from = find_set_and_id(inst, nla_data(attr[IPSET_ATTR_SETNAME]),
 			       &from_id);
-	if (from == NULL)
+	if (!from)
 		return -ENOENT;
 
 	to = find_set_and_id(inst, nla_data(attr[IPSET_ATTR_SETNAME2]),
 			     &to_id);
-	if (to == NULL)
+	if (!to)
 		return -IPSET_ERR_EXIST_SETNAME2;
 
 	/* Features must not change.
-	 * Not an artificial restriction anymore, as we must prevent
-	 * possible loops created by swapping in setlist type of sets. */
+	 * Not an artifical restriction anymore, as we must prevent
+	 * possible loops created by swapping in setlist type of sets.
+	 */
 	if (!(from->type->features == to->type->features &&
 	      from->family == to->family))
 		return -IPSET_ERR_TYPE_MISMATCH;
@@ -1202,12 +1202,16 @@ ip_set_swap(struct sock *ctnl, struct sk_buff *skb,
 static int
 ip_set_dump_done(struct netlink_callback *cb)
 {
-	struct ip_set_net *inst = (struct ip_set_net *)cb->args[IPSET_CB_NET];
 	if (cb->args[IPSET_CB_ARG0]) {
-		pr_debug("release set %s\n",
-			 ip_set(inst, cb->args[IPSET_CB_INDEX])->name);
-		__ip_set_put_byindex(inst,
-			(ip_set_id_t) cb->args[IPSET_CB_INDEX]);
+		struct ip_set_net *inst =
+			(struct ip_set_net *)cb->args[IPSET_CB_NET];
+		ip_set_id_t index = (ip_set_id_t)cb->args[IPSET_CB_INDEX];
+		struct ip_set *set = ip_set(inst, index);
+
+		if (set->variant->uref)
+			set->variant->uref(set, cb, false);
+		pr_debug("release set %s\n", set->name);
+		__ip_set_put_byindex(inst, index);
 	}
 	return 0;
 }
@@ -1229,7 +1233,7 @@ dump_init(struct netlink_callback *cb, struct ip_set_net *inst)
 {
 	struct nlmsghdr *nlh = nlmsg_hdr(cb->skb);
 	int min_len = nlmsg_total_size(sizeof(struct nfgenmsg));
-	struct nlattr *cda[IPSET_ATTR_CMD_MAX+1];
+	struct nlattr *cda[IPSET_ATTR_CMD_MAX + 1];
 	struct nlattr *attr = (void *)nlh + min_len;
 	u32 dump_type;
 	ip_set_id_t index;
@@ -1238,27 +1242,23 @@ dump_init(struct netlink_callback *cb, struct ip_set_net *inst)
 	nla_parse(cda, IPSET_ATTR_CMD_MAX,
 		  attr, nlh->nlmsg_len - min_len, ip_set_setname_policy);
 
-	/* cb->args[IPSET_CB_NET]:	net namespace
-	 *         [IPSET_CB_DUMP]:	dump single set/all sets
-	 *         [IPSET_CB_INDEX]: 	set index
-	 *         [IPSET_CB_ARG0]:	type specific
-	 */
-
 	if (cda[IPSET_ATTR_SETNAME]) {
 		struct ip_set *set;
 
 		set = find_set_and_id(inst, nla_data(cda[IPSET_ATTR_SETNAME]),
 				      &index);
-		if (set == NULL)
+		if (!set)
 			return -ENOENT;
 
 		dump_type = DUMP_ONE;
 		cb->args[IPSET_CB_INDEX] = index;
-	} else
+	} else {
 		dump_type = DUMP_ALL;
+	}
 
 	if (cda[IPSET_ATTR_FLAGS]) {
 		u32 f = ip_set_get_h32(cda[IPSET_ATTR_FLAGS]);
+
 		dump_type |= (f << 16);
 	}
 	cb->args[IPSET_CB_NET] = (unsigned long)inst;
@@ -1276,6 +1276,7 @@ ip_set_dump_start(struct sk_buff *skb, struct netlink_callback *cb)
 	unsigned int flags = NETLINK_CB(cb->skb).portid ? NLM_F_MULTI : 0;
 	struct ip_set_net *inst = ip_set_pernet(sock_net(skb->sk));
 	u32 dump_type, dump_flags;
+	bool is_destroyed;
 	int ret = 0;
 
 	if (!cb->args[IPSET_CB_DUMP]) {
@@ -1283,7 +1284,8 @@ ip_set_dump_start(struct sk_buff *skb, struct netlink_callback *cb)
 		if (ret < 0) {
 			nlh = nlmsg_hdr(cb->skb);
 			/* We have to create and send the error message
-			 * manually :-( */
+			 * manually :-(
+			 */
 			if (nlh->nlmsg_flags & NLM_F_ACK)
 				netlink_ack(cb->skb, nlh, ret);
 			return ret;
@@ -1301,13 +1303,21 @@ dump_last:
 	pr_debug("dump type, flag: %u %u index: %ld\n",
 		 dump_type, dump_flags, cb->args[IPSET_CB_INDEX]);
 	for (; cb->args[IPSET_CB_INDEX] < max; cb->args[IPSET_CB_INDEX]++) {
-		index = (ip_set_id_t) cb->args[IPSET_CB_INDEX];
+		index = (ip_set_id_t)cb->args[IPSET_CB_INDEX];
+		write_lock_bh(&ip_set_ref_lock);
 		set = ip_set(inst, index);
-		if (set == NULL) {
+		is_destroyed = inst->is_destroyed;
+		if (!set || is_destroyed) {
+			write_unlock_bh(&ip_set_ref_lock);
 			if (dump_type == DUMP_ONE) {
 				ret = -ENOENT;
 				goto out;
 			}
+			if (is_destroyed) {
+				/* All sets are just being destroyed */
+				ret = 0;
+				goto out;
+			}
 			continue;
 		}
 		/* When dumping all sets, we must dump "sorted"
@@ -1315,14 +1325,17 @@ dump_last:
 		 */
 		if (dump_type != DUMP_ONE &&
 		    ((dump_type == DUMP_ALL) ==
-		     !!(set->type->features & IPSET_DUMP_LAST)))
+		     !!(set->type->features & IPSET_DUMP_LAST))) {
+			write_unlock_bh(&ip_set_ref_lock);
 			continue;
+		}
 		pr_debug("List set: %s\n", set->name);
 		if (!cb->args[IPSET_CB_ARG0]) {
 			/* Start listing: make sure set won't be destroyed */
 			pr_debug("reference set\n");
-			__ip_set_get(set);
+			set->ref++;
 		}
+		write_unlock_bh(&ip_set_ref_lock);
 		nlh = start_msg(skb, NETLINK_CB(cb->skb).portid,
 				cb->nlh->nlmsg_seq, flags,
 				IPSET_CMD_LIST);
@@ -1350,11 +1363,13 @@ dump_last:
 				goto release_refcount;
 			if (dump_flags & IPSET_FLAG_LIST_HEADER)
 				goto next_set;
+			if (set->variant->uref)
+				set->variant->uref(set, cb, true);
 			/* Fall through and add elements */
 		default:
-			read_lock_bh(&set->lock);
+			rcu_read_lock_bh();
 			ret = set->variant->list(set, skb, cb);
-			read_unlock_bh(&set->lock);
+			rcu_read_unlock_bh();
 			if (!cb->args[IPSET_CB_ARG0])
 				/* Set is done, proceed with next one */
 				goto next_set;
@@ -1366,6 +1381,8 @@ dump_last:
 		dump_type = DUMP_LAST;
 		cb->args[IPSET_CB_DUMP] = dump_type | (dump_flags << 16);
 		cb->args[IPSET_CB_INDEX] = 0;
+		if (set && set->variant->uref)
+			set->variant->uref(set, cb, false);
 		goto dump_last;
 	}
 	goto out;
@@ -1380,7 +1397,10 @@ next_set:
 release_refcount:
 	/* If there was an error or set is done, release set */
 	if (ret || !cb->args[IPSET_CB_ARG0]) {
-		pr_debug("release set %s\n", ip_set(inst, index)->name);
+		set = ip_set(inst, index);
+		if (set->variant->uref)
+			set->variant->uref(set, cb, false);
+		pr_debug("release set %s\n", set->name);
 		__ip_set_put_byindex(inst, index);
 		cb->args[IPSET_CB_ARG0] = 0;
 	}
@@ -1432,9 +1452,9 @@ call_ad(struct sock *ctnl, struct sk_buff *skb, struct ip_set *set,
 	bool eexist = flags & IPSET_FLAG_EXIST, retried = false;
 
 	do {
-		write_lock_bh(&set->lock);
+		spin_lock_bh(&set->lock);
 		ret = set->variant->uadt(set, tb, adt, &lineno, flags, retried);
-		write_unlock_bh(&set->lock);
+		spin_unlock_bh(&set->lock);
 		retried = true;
 	} while (ret == -EAGAIN &&
 		 set->variant->resize &&
@@ -1450,12 +1470,12 @@ call_ad(struct sock *ctnl, struct sk_buff *skb, struct ip_set *set,
 		size_t payload = min(SIZE_MAX,
 				     sizeof(*errmsg) + nlmsg_len(nlh));
 		int min_len = nlmsg_total_size(sizeof(struct nfgenmsg));
-		struct nlattr *cda[IPSET_ATTR_CMD_MAX+1];
+		struct nlattr *cda[IPSET_ATTR_CMD_MAX + 1];
 		struct nlattr *cmdattr;
 		u32 *errline;
 
 		skb2 = nlmsg_new(payload, GFP_KERNEL);
-		if (skb2 == NULL)
+		if (!skb2)
 			return -ENOMEM;
 		rep = __nlmsg_put(skb2, NETLINK_CB(skb).portid,
 				  nlh->nlmsg_seq, NLMSG_ERROR, payload, 0);
@@ -1472,7 +1492,8 @@ call_ad(struct sock *ctnl, struct sk_buff *skb, struct ip_set *set,
 
 		*errline = lineno;
 
-		netlink_unicast(ctnl, skb2, NETLINK_CB(skb).portid, MSG_DONTWAIT);
+		netlink_unicast(ctnl, skb2, NETLINK_CB(skb).portid,
+				MSG_DONTWAIT);
 		/* Signal netlink not to send its ACK/errmsg.  */
 		return -EINTR;
 	}
@@ -1487,25 +1508,25 @@ ip_set_uadd(struct sock *ctnl, struct sk_buff *skb,
 {
 	struct ip_set_net *inst = ip_set_pernet(sock_net(ctnl));
 	struct ip_set *set;
-	struct nlattr *tb[IPSET_ATTR_ADT_MAX+1] = {};
+	struct nlattr *tb[IPSET_ATTR_ADT_MAX + 1] = {};
 	const struct nlattr *nla;
 	u32 flags = flag_exist(nlh);
 	bool use_lineno;
 	int ret = 0;
 
 	if (unlikely(protocol_failed(attr) ||
-		     attr[IPSET_ATTR_SETNAME] == NULL ||
+		     !attr[IPSET_ATTR_SETNAME] ||
 		     !((attr[IPSET_ATTR_DATA] != NULL) ^
 		       (attr[IPSET_ATTR_ADT] != NULL)) ||
-		     (attr[IPSET_ATTR_DATA] != NULL &&
+		     (attr[IPSET_ATTR_DATA] &&
 		      !flag_nested(attr[IPSET_ATTR_DATA])) ||
-		     (attr[IPSET_ATTR_ADT] != NULL &&
+		     (attr[IPSET_ATTR_ADT] &&
 		      (!flag_nested(attr[IPSET_ATTR_ADT]) ||
-		       attr[IPSET_ATTR_LINENO] == NULL))))
+		       !attr[IPSET_ATTR_LINENO]))))
 		return -IPSET_ERR_PROTOCOL;
 
 	set = find_set(inst, nla_data(attr[IPSET_ATTR_SETNAME]));
-	if (set == NULL)
+	if (!set)
 		return -ENOENT;
 
 	use_lineno = !!attr[IPSET_ATTR_LINENO];
@@ -1542,25 +1563,25 @@ ip_set_udel(struct sock *ctnl, struct sk_buff *skb,
 {
 	struct ip_set_net *inst = ip_set_pernet(sock_net(ctnl));
 	struct ip_set *set;
-	struct nlattr *tb[IPSET_ATTR_ADT_MAX+1] = {};
+	struct nlattr *tb[IPSET_ATTR_ADT_MAX + 1] = {};
 	const struct nlattr *nla;
 	u32 flags = flag_exist(nlh);
 	bool use_lineno;
 	int ret = 0;
 
 	if (unlikely(protocol_failed(attr) ||
-		     attr[IPSET_ATTR_SETNAME] == NULL ||
+		     !attr[IPSET_ATTR_SETNAME] ||
 		     !((attr[IPSET_ATTR_DATA] != NULL) ^
 		       (attr[IPSET_ATTR_ADT] != NULL)) ||
-		     (attr[IPSET_ATTR_DATA] != NULL &&
+		     (attr[IPSET_ATTR_DATA] &&
 		      !flag_nested(attr[IPSET_ATTR_DATA])) ||
-		     (attr[IPSET_ATTR_ADT] != NULL &&
+		     (attr[IPSET_ATTR_ADT] &&
 		      (!flag_nested(attr[IPSET_ATTR_ADT]) ||
-		       attr[IPSET_ATTR_LINENO] == NULL))))
+		       !attr[IPSET_ATTR_LINENO]))))
 		return -IPSET_ERR_PROTOCOL;
 
 	set = find_set(inst, nla_data(attr[IPSET_ATTR_SETNAME]));
-	if (set == NULL)
+	if (!set)
 		return -ENOENT;
 
 	use_lineno = !!attr[IPSET_ATTR_LINENO];
@@ -1597,26 +1618,26 @@ ip_set_utest(struct sock *ctnl, struct sk_buff *skb,
 {
 	struct ip_set_net *inst = ip_set_pernet(sock_net(ctnl));
 	struct ip_set *set;
-	struct nlattr *tb[IPSET_ATTR_ADT_MAX+1] = {};
+	struct nlattr *tb[IPSET_ATTR_ADT_MAX + 1] = {};
 	int ret = 0;
 
 	if (unlikely(protocol_failed(attr) ||
-		     attr[IPSET_ATTR_SETNAME] == NULL ||
-		     attr[IPSET_ATTR_DATA] == NULL ||
+		     !attr[IPSET_ATTR_SETNAME] ||
+		     !attr[IPSET_ATTR_DATA] ||
 		     !flag_nested(attr[IPSET_ATTR_DATA])))
 		return -IPSET_ERR_PROTOCOL;
 
 	set = find_set(inst, nla_data(attr[IPSET_ATTR_SETNAME]));
-	if (set == NULL)
+	if (!set)
 		return -ENOENT;
 
 	if (nla_parse_nested(tb, IPSET_ATTR_ADT_MAX, attr[IPSET_ATTR_DATA],
 			     set->type->adt_policy))
 		return -IPSET_ERR_PROTOCOL;
 
-	read_lock_bh(&set->lock);
+	rcu_read_lock_bh();
 	ret = set->variant->uadt(set, tb, IPSET_TEST, NULL, 0, 0);
-	read_unlock_bh(&set->lock);
+	rcu_read_unlock_bh();
 	/* Userspace can't trigger element to be re-added */
 	if (ret == -EAGAIN)
 		ret = 1;
@@ -1638,15 +1659,15 @@ ip_set_header(struct sock *ctnl, struct sk_buff *skb,
 	int ret = 0;
 
 	if (unlikely(protocol_failed(attr) ||
-		     attr[IPSET_ATTR_SETNAME] == NULL))
+		     !attr[IPSET_ATTR_SETNAME]))
 		return -IPSET_ERR_PROTOCOL;
 
 	set = find_set(inst, nla_data(attr[IPSET_ATTR_SETNAME]));
-	if (set == NULL)
+	if (!set)
 		return -ENOENT;
 
 	skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
-	if (skb2 == NULL)
+	if (!skb2)
 		return -ENOMEM;
 
 	nlh2 = start_msg(skb2, NETLINK_CB(skb).portid, nlh->nlmsg_seq, 0,
@@ -1695,8 +1716,8 @@ ip_set_type(struct sock *ctnl, struct sk_buff *skb,
 	int ret = 0;
 
 	if (unlikely(protocol_failed(attr) ||
-		     attr[IPSET_ATTR_TYPENAME] == NULL ||
-		     attr[IPSET_ATTR_FAMILY] == NULL))
+		     !attr[IPSET_ATTR_TYPENAME] ||
+		     !attr[IPSET_ATTR_FAMILY]))
 		return -IPSET_ERR_PROTOCOL;
 
 	family = nla_get_u8(attr[IPSET_ATTR_FAMILY]);
@@ -1706,7 +1727,7 @@ ip_set_type(struct sock *ctnl, struct sk_buff *skb,
 		return ret;
 
 	skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
-	if (skb2 == NULL)
+	if (!skb2)
 		return -ENOMEM;
 
 	nlh2 = start_msg(skb2, NETLINK_CB(skb).portid, nlh->nlmsg_seq, 0,
@@ -1751,11 +1772,11 @@ ip_set_protocol(struct sock *ctnl, struct sk_buff *skb,
 	struct nlmsghdr *nlh2;
 	int ret = 0;
 
-	if (unlikely(attr[IPSET_ATTR_PROTOCOL] == NULL))
+	if (unlikely(!attr[IPSET_ATTR_PROTOCOL]))
 		return -IPSET_ERR_PROTOCOL;
 
 	skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
-	if (skb2 == NULL)
+	if (!skb2)
 		return -ENOMEM;
 
 	nlh2 = start_msg(skb2, NETLINK_CB(skb).portid, nlh->nlmsg_seq, 0,
@@ -1883,7 +1904,7 @@ ip_set_sockfn_get(struct sock *sk, int optval, void __user *user, int *len)
 		ret = -EFAULT;
 		goto done;
 	}
-	op = (unsigned int *) data;
+	op = (unsigned int *)data;
 
 	if (*op < IP_SET_OP_VERSION) {
 		/* Check the version at the beginning of operations */
@@ -1995,10 +2016,11 @@ ip_set_net_init(struct net *net)
 	if (inst->ip_set_max >= IPSET_INVALID_ID)
 		inst->ip_set_max = IPSET_INVALID_ID - 1;
 
-	list = kzalloc(sizeof(struct ip_set *) * inst->ip_set_max, GFP_KERNEL);
+	list = kcalloc(inst->ip_set_max, sizeof(struct ip_set *), GFP_KERNEL);
 	if (!list)
 		return -ENOMEM;
-	inst->is_deleted = 0;
+	inst->is_deleted = false;
+	inst->is_destroyed = false;
 	rcu_assign_pointer(inst->ip_set_list, list);
 	return 0;
 }
@@ -2011,12 +2033,14 @@ ip_set_net_exit(struct net *net)
 	struct ip_set *set = NULL;
 	ip_set_id_t i;
 
-	inst->is_deleted = 1; /* flag for ip_set_nfnl_put */
+	inst->is_deleted = true; /* flag for ip_set_nfnl_put */
 
 	for (i = 0; i < inst->ip_set_max; i++) {
 		set = ip_set(inst, i);
-		if (set != NULL)
-			ip_set_destroy_set(inst, i);
+		if (set) {
+			ip_set(inst, i) = NULL;
+			ip_set_destroy_set(set);
+		}
 	}
 	kfree(rcu_dereference_protected(inst->ip_set_list, 1));
 }
@@ -2028,11 +2052,11 @@ static struct pernet_operations ip_set_net_ops = {
 	.size	= sizeof(struct ip_set_net)
 };
 
-
 static int __init
 ip_set_init(void)
 {
 	int ret = nfnetlink_subsys_register(&ip_set_netlink_subsys);
+
 	if (ret != 0) {
 		pr_err("ip_set: cannot register with nfnetlink.\n");
 		return ret;