Merge branch 'master' of git://blackhole.kfki.hu/nf

Jozsef Kadlecsik says:

====================
ipset patches for nf

The first one is larger than usual, but the issue could not be solved simpler.
Also, it's a resend of the patch I submitted a few days ago, with a one line
fix on top of that: the size of the comment extensions was not taken into
account at reporting the full size of the set.

- Fix "INFO: rcu detected stall in hash_xxx" reports of syzbot
  by introducing region locking and using workqueue instead of timer based
  gc of timed out entries in hash types of sets in ipset.
- Fix the forceadd evaluation path - the bug was also uncovered by the syzbot.
====================
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

include/linux/netfilter/ipset/ip_set.h

@@ -121,6 +121,7 @@ struct ip_set_ext {
 	u32 timeout;
 	u8 packets_op;
 	u8 bytes_op;
+	bool target;
 };
 
 struct ip_set;
@@ -187,6 +188,14 @@ struct ip_set_type_variant {
 	/* Return true if "b" set is the same as "a"
 	 * according to the create set parameters */
 	bool (*same_set)(const struct ip_set *a, const struct ip_set *b);
+	/* Region-locking is used */
+	bool region_lock;
+};
+
+struct ip_set_region {
+	spinlock_t lock;	/* Region lock */
+	size_t ext_size;	/* Size of the dynamic extensions */
+	u32 elements;		/* Number of elements vs timeout */
 };
 
 /* The core set type structure */
@@ -501,7 +510,7 @@ ip_set_init_skbinfo(struct ip_set_skbinfo *skbinfo,
 }
 
 #define IP_SET_INIT_KEXT(skb, opt, set)			\
-	{ .bytes = (skb)->len, .packets = 1,		\
+	{ .bytes = (skb)->len, .packets = 1, .target = true,\
 	  .timeout = ip_set_adt_opt_timeout(opt, set) }
 
 #define IP_SET_INIT_UEXT(set)				\

net/netfilter/ipset/ip_set_core.c

@@ -723,6 +723,20 @@ ip_set_rcu_get(struct net *net, ip_set_id_t index)
 	return set;
 }
 
+static inline void
+ip_set_lock(struct ip_set *set)
+{
+	if (!set->variant->region_lock)
+		spin_lock_bh(&set->lock);
+}
+
+static inline void
+ip_set_unlock(struct ip_set *set)
+{
+	if (!set->variant->region_lock)
+		spin_unlock_bh(&set->lock);
+}
+
 int
 ip_set_test(ip_set_id_t index, const struct sk_buff *skb,
 	    const struct xt_action_param *par, struct ip_set_adt_opt *opt)
@@ -744,9 +758,9 @@ ip_set_test(ip_set_id_t index, const struct sk_buff *skb,
 	if (ret == -EAGAIN) {
 		/* Type requests element to be completed */
 		pr_debug("element must be completed, ADD is triggered\n");
-		spin_lock_bh(&set->lock);
+		ip_set_lock(set);
 		set->variant->kadt(set, skb, par, IPSET_ADD, opt);
-		spin_unlock_bh(&set->lock);
+		ip_set_unlock(set);
 		ret = 1;
 	} else {
 		/* --return-nomatch: invert matched element */
@@ -775,9 +789,9 @@ ip_set_add(ip_set_id_t index, const struct sk_buff *skb,
 	    !(opt->family == set->family || set->family == NFPROTO_UNSPEC))
 		return -IPSET_ERR_TYPE_MISMATCH;
 
-	spin_lock_bh(&set->lock);
+	ip_set_lock(set);
 	ret = set->variant->kadt(set, skb, par, IPSET_ADD, opt);
-	spin_unlock_bh(&set->lock);
+	ip_set_unlock(set);
 
 	return ret;
 }
@@ -797,9 +811,9 @@ ip_set_del(ip_set_id_t index, const struct sk_buff *skb,
 	    !(opt->family == set->family || set->family == NFPROTO_UNSPEC))
 		return -IPSET_ERR_TYPE_MISMATCH;
 
-	spin_lock_bh(&set->lock);
+	ip_set_lock(set);
 	ret = set->variant->kadt(set, skb, par, IPSET_DEL, opt);
-	spin_unlock_bh(&set->lock);
+	ip_set_unlock(set);
 
 	return ret;
 }
@@ -1264,9 +1278,9 @@ ip_set_flush_set(struct ip_set *set)
 {
 	pr_debug("set: %s\n",  set->name);
 
-	spin_lock_bh(&set->lock);
+	ip_set_lock(set);
 	set->variant->flush(set);
-	spin_unlock_bh(&set->lock);
+	ip_set_unlock(set);
 }
 
 static int ip_set_flush(struct net *net, struct sock *ctnl, struct sk_buff *skb,
@@ -1713,9 +1727,9 @@ call_ad(struct sock *ctnl, struct sk_buff *skb, struct ip_set *set,
 	bool eexist = flags & IPSET_FLAG_EXIST, retried = false;
 
 	do {
-		spin_lock_bh(&set->lock);
+		ip_set_lock(set);
 		ret = set->variant->uadt(set, tb, adt, &lineno, flags, retried);
-		spin_unlock_bh(&set->lock);
+		ip_set_unlock(set);
 		retried = true;
 	} while (ret == -EAGAIN &&
 		 set->variant->resize &&