3 files changed, 39 insertions, 31 deletions

diff --git a/net/netfilter/ipset/ip_set_core.c b/net/netfilter/ipset/ip_set_core.c
index bc4bd247bb7d..1577f2f76060 100644
--- a/net/netfilter/ipset/ip_set_core.c
+++ b/net/netfilter/ipset/ip_set_core.c
@@ -55,11 +55,15 @@ MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>");
 MODULE_DESCRIPTION("core IP set support");
 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_IPSET);
 
-/* When the nfnl mutex is held: */
+/* When the nfnl mutex or ip_set_ref_lock is held: */
 #define ip_set_dereference(p)		\
-	rcu_dereference_protected(p, lockdep_nfnl_is_held(NFNL_SUBSYS_IPSET))
+	rcu_dereference_protected(p,	\
+		lockdep_nfnl_is_held(NFNL_SUBSYS_IPSET) || \
+		lockdep_is_held(&ip_set_ref_lock))
 #define ip_set(inst, id)		\
 	ip_set_dereference((inst)->ip_set_list)[id]
+#define ip_set_ref_netlink(inst,id)	\
+	rcu_dereference_raw((inst)->ip_set_list)[id]
 
 /* The set types are implemented in modules and registered set types
  * can be found in ip_set_type_list. Adding/deleting types is
@@ -693,21 +697,20 @@ 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.
- * 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.
- *
+ * Set itself is protected by RCU, but its name isn't: to protect against
+ * renaming, grab ip_set_ref_lock as reader (see ip_set_rename()) and copy the
+ * name.
  */
-const char *
-ip_set_name_byindex(struct net *net, ip_set_id_t index)
+void
+ip_set_name_byindex(struct net *net, ip_set_id_t index, char *name)
 {
-	const struct ip_set *set = ip_set_rcu_get(net, index);
+	struct ip_set *set = ip_set_rcu_get(net, index);
 
 	BUG_ON(!set);
-	BUG_ON(set->ref == 0);
 
-	/* Referenced, so it's safe */
-	return set->name;
+	read_lock_bh(&ip_set_ref_lock);
+	strncpy(name, set->name, IPSET_MAXNAMELEN);
+	read_unlock_bh(&ip_set_ref_lock);
 }
 EXPORT_SYMBOL_GPL(ip_set_name_byindex);
 
@@ -961,7 +964,7 @@ static int ip_set_create(struct net *net, struct sock *ctnl,
 			/* Wraparound */
 			goto cleanup;
 
-		list = kcalloc(i, sizeof(struct ip_set *), GFP_KERNEL);
+		list = kvcalloc(i, sizeof(struct ip_set *), GFP_KERNEL);
 		if (!list)
 			goto cleanup;
 		/* nfnl mutex is held, both lists are valid */
@@ -973,7 +976,7 @@ static int ip_set_create(struct net *net, struct sock *ctnl,
 		/* Use new list */
 		index = inst->ip_set_max;
 		inst->ip_set_max = i;
-		kfree(tmp);
+		kvfree(tmp);
 		ret = 0;
 	} else if (ret) {
 		goto cleanup;
@@ -1153,7 +1156,7 @@ static int ip_set_rename(struct net *net, struct sock *ctnl,
 	if (!set)
 		return -ENOENT;
 
-	read_lock_bh(&ip_set_ref_lock);
+	write_lock_bh(&ip_set_ref_lock);
 	if (set->ref != 0) {
 		ret = -IPSET_ERR_REFERENCED;
 		goto out;
@@ -1170,7 +1173,7 @@ static int ip_set_rename(struct net *net, struct sock *ctnl,
 	strncpy(set->name, name2, IPSET_MAXNAMELEN);
 
 out:
-	read_unlock_bh(&ip_set_ref_lock);
+	write_unlock_bh(&ip_set_ref_lock);
 	return ret;
 }
 
@@ -1252,7 +1255,7 @@ ip_set_dump_done(struct netlink_callback *cb)
 		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);
+		struct ip_set *set = ip_set_ref_netlink(inst, index);
 
 		if (set->variant->uref)
 			set->variant->uref(set, cb, false);
@@ -1441,7 +1444,7 @@ next_set:
 release_refcount:
 	/* If there was an error or set is done, release set */
 	if (ret || !cb->args[IPSET_CB_ARG0]) {
-		set = ip_set(inst, index);
+		set = ip_set_ref_netlink(inst, index);
 		if (set->variant->uref)
 			set->variant->uref(set, cb, false);
 		pr_debug("release set %s\n", set->name);
@@ -2059,7 +2062,7 @@ ip_set_net_init(struct net *net)
 	if (inst->ip_set_max >= IPSET_INVALID_ID)
 		inst->ip_set_max = IPSET_INVALID_ID - 1;
 
-	list = kcalloc(inst->ip_set_max, sizeof(struct ip_set *), GFP_KERNEL);
+	list = kvcalloc(inst->ip_set_max, sizeof(struct ip_set *), GFP_KERNEL);
 	if (!list)
 		return -ENOMEM;
 	inst->is_deleted = false;
@@ -2087,7 +2090,7 @@ ip_set_net_exit(struct net *net)
 		}
 	}
 	nfnl_unlock(NFNL_SUBSYS_IPSET);
-	kfree(rcu_dereference_protected(inst->ip_set_list, 1));
+	kvfree(rcu_dereference_protected(inst->ip_set_list, 1));
 }
 
 static struct pernet_operations ip_set_net_ops = {
diff --git a/net/netfilter/ipset/ip_set_hash_netportnet.c b/net/netfilter/ipset/ip_set_hash_netportnet.c
index d391485a6acd..613e18e720a4 100644
--- a/net/netfilter/ipset/ip_set_hash_netportnet.c
+++ b/net/netfilter/ipset/ip_set_hash_netportnet.c
@@ -213,13 +213,13 @@ hash_netportnet4_uadt(struct ip_set *set, struct nlattr *tb[],
 
 	if (tb[IPSET_ATTR_CIDR]) {
 		e.cidr[0] = nla_get_u8(tb[IPSET_ATTR_CIDR]);
-		if (!e.cidr[0] || e.cidr[0] > HOST_MASK)
+		if (e.cidr[0] > HOST_MASK)
 			return -IPSET_ERR_INVALID_CIDR;
 	}
 
 	if (tb[IPSET_ATTR_CIDR2]) {
 		e.cidr[1] = nla_get_u8(tb[IPSET_ATTR_CIDR2]);
-		if (!e.cidr[1] || e.cidr[1] > HOST_MASK)
+		if (e.cidr[1] > HOST_MASK)
 			return -IPSET_ERR_INVALID_CIDR;
 	}
 
@@ -493,13 +493,13 @@ hash_netportnet6_uadt(struct ip_set *set, struct nlattr *tb[],
 
 	if (tb[IPSET_ATTR_CIDR]) {
 		e.cidr[0] = nla_get_u8(tb[IPSET_ATTR_CIDR]);
-		if (!e.cidr[0] || e.cidr[0] > HOST_MASK)
+		if (e.cidr[0] > HOST_MASK)
 			return -IPSET_ERR_INVALID_CIDR;
 	}
 
 	if (tb[IPSET_ATTR_CIDR2]) {
 		e.cidr[1] = nla_get_u8(tb[IPSET_ATTR_CIDR2]);
-		if (!e.cidr[1] || e.cidr[1] > HOST_MASK)
+		if (e.cidr[1] > HOST_MASK)
 			return -IPSET_ERR_INVALID_CIDR;
 	}
 
diff --git a/net/netfilter/ipset/ip_set_list_set.c b/net/netfilter/ipset/ip_set_list_set.c
index 072a658fde04..8da228da53ae 100644
--- a/net/netfilter/ipset/ip_set_list_set.c
+++ b/net/netfilter/ipset/ip_set_list_set.c
@@ -148,9 +148,7 @@ __list_set_del_rcu(struct rcu_head * rcu)
 {
 	struct set_elem *e = container_of(rcu, struct set_elem, rcu);
 	struct ip_set *set = e->set;
-	struct list_set *map = set->data;
 
-	ip_set_put_byindex(map->net, e->id);
 	ip_set_ext_destroy(set, e);
 	kfree(e);
 }
@@ -158,15 +156,21 @@ __list_set_del_rcu(struct rcu_head * rcu)
 static inline void
 list_set_del(struct ip_set *set, struct set_elem *e)
 {
+	struct list_set *map = set->data;
+
 	set->elements--;
 	list_del_rcu(&e->list);
+	ip_set_put_byindex(map->net, e->id);
 	call_rcu(&e->rcu, __list_set_del_rcu);
 }
 
 static inline void
-list_set_replace(struct set_elem *e, struct set_elem *old)
+list_set_replace(struct ip_set *set, struct set_elem *e, struct set_elem *old)
 {
+	struct list_set *map = set->data;
+
 	list_replace_rcu(&old->list, &e->list);
+	ip_set_put_byindex(map->net, old->id);
 	call_rcu(&old->rcu, __list_set_del_rcu);
 }
 
@@ -298,7 +302,7 @@ list_set_uadd(struct ip_set *set, void *value, const struct ip_set_ext *ext,
 	INIT_LIST_HEAD(&e->list);
 	list_set_init_extensions(set, ext, e);
 	if (n)
-		list_set_replace(e, n);
+		list_set_replace(set, e, n);
 	else if (next)
 		list_add_tail_rcu(&e->list, &next->list);
 	else if (prev)
@@ -486,6 +490,7 @@ list_set_list(const struct ip_set *set,
 	const struct list_set *map = set->data;
 	struct nlattr *atd, *nested;
 	u32 i = 0, first = cb->args[IPSET_CB_ARG0];
+	char name[IPSET_MAXNAMELEN];
 	struct set_elem *e;
 	int ret = 0;
 
@@ -504,8 +509,8 @@ list_set_list(const struct ip_set *set,
 		nested = ipset_nest_start(skb, IPSET_ATTR_DATA);
 		if (!nested)
 			goto nla_put_failure;
-		if (nla_put_string(skb, IPSET_ATTR_NAME,
-				   ip_set_name_byindex(map->net, e->id)))
+		ip_set_name_byindex(map->net, e->id, name);
+		if (nla_put_string(skb, IPSET_ATTR_NAME, name))
 			goto nla_put_failure;
 		if (ip_set_put_extensions(skb, set, e, true))
 			goto nla_put_failure;
@@ -526,8 +531,8 @@ nla_put_failure:
 		ret = -EMSGSIZE;
 	} else {
 		cb->args[IPSET_CB_ARG0] = i;
+		ipset_nest_end(skb, atd);
 	}
-	ipset_nest_end(skb, atd);
 out:
 	rcu_read_unlock();
 	return ret;