Merge tag 'nf-23-09-20' of https://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf

Florian Westphal says:

====================
netfilter updates for net

The following three patches fix regressions in the netfilter subsystem:

1. Reject attempts to repeatedly toggle the 'dormant' flag in a single
   transaction.  Doing so makes nf_tables lose track of the real state
   vs. the desired state.  This ends with an attempt to unregister hooks
   that were never registered in the first place, which yields a splat.

2. Fix element counting in the new nftables garbage collection infra
   that came with 6.5:  More than 255 expired elements wraps a counter
   which results in memory leak.

3. Since 6.4 ipset can BUG when a set is renamed while a CREATE command
   is in progress, fix from Jozsef Kadlecsik.

* tag 'nf-23-09-20' of https://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
  netfilter: ipset: Fix race between IPSET_CMD_CREATE and IPSET_CMD_SWAP
  netfilter: nf_tables: fix memleak when more than 255 elements expired
  netfilter: nf_tables: disable toggling dormant table state more than once
====================

Link: https://lore.kernel.org/r/20230920084156.4192-1-fw@strlen.de
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Author: Paolo Abeni

include/net/netfilter/nf_tables.h

@@ -1682,7 +1682,7 @@ struct nft_trans_gc {
 	struct net		*net;
 	struct nft_set		*set;
 	u32			seq;
-	u8			count;
+	u16			count;
 	void			*priv[NFT_TRANS_GC_BATCHCOUNT];
 	struct rcu_head		rcu;
 };

net/netfilter/ipset/ip_set_core.c

@@ -682,6 +682,14 @@ __ip_set_put(struct ip_set *set)
 /* set->ref can be swapped out by ip_set_swap, netlink events (like dump) need
  * a separate reference counter
  */
+static void
+__ip_set_get_netlink(struct ip_set *set)
+{
+	write_lock_bh(&ip_set_ref_lock);
+	set->ref_netlink++;
+	write_unlock_bh(&ip_set_ref_lock);
+}
+
 static void
 __ip_set_put_netlink(struct ip_set *set)
 {
@@ -1693,11 +1701,11 @@ call_ad(struct net *net, struct sock *ctnl, struct sk_buff *skb,
 
 	do {
 		if (retried) {
-			__ip_set_get(set);
+			__ip_set_get_netlink(set);
 			nfnl_unlock(NFNL_SUBSYS_IPSET);
 			cond_resched();
 			nfnl_lock(NFNL_SUBSYS_IPSET);
-			__ip_set_put(set);
+			__ip_set_put_netlink(set);
 		}
 
 		ip_set_lock(set);

net/netfilter/nf_tables_api.c

@@ -1219,6 +1219,10 @@ static int nf_tables_updtable(struct nft_ctx *ctx)
 	     flags & NFT_TABLE_F_OWNER))
 		return -EOPNOTSUPP;
 
+	/* No dormant off/on/off/on games in single transaction */
+	if (ctx->table->flags & __NFT_TABLE_F_UPDATE)
+		return -EINVAL;
+
 	trans = nft_trans_alloc(ctx, NFT_MSG_NEWTABLE,
 				sizeof(struct nft_trans_table));
 	if (trans == NULL)
@@ -9575,12 +9579,15 @@ static int nft_trans_gc_space(struct nft_trans_gc *trans)
 struct nft_trans_gc *nft_trans_gc_queue_async(struct nft_trans_gc *gc,
 					      unsigned int gc_seq, gfp_t gfp)
 {
+	struct nft_set *set;
+
 	if (nft_trans_gc_space(gc))
 		return gc;
 
+	set = gc->set;
 	nft_trans_gc_queue_work(gc);
 
-	return nft_trans_gc_alloc(gc->set, gc_seq, gfp);
+	return nft_trans_gc_alloc(set, gc_seq, gfp);
 }
 
 void nft_trans_gc_queue_async_done(struct nft_trans_gc *trans)
@@ -9595,15 +9602,18 @@ void nft_trans_gc_queue_async_done(struct nft_trans_gc *trans)
 
 struct nft_trans_gc *nft_trans_gc_queue_sync(struct nft_trans_gc *gc, gfp_t gfp)
 {
+	struct nft_set *set;
+
 	if (WARN_ON_ONCE(!lockdep_commit_lock_is_held(gc->net)))
 		return NULL;
 
 	if (nft_trans_gc_space(gc))
 		return gc;
 
+	set = gc->set;
 	call_rcu(&gc->rcu, nft_trans_gc_trans_free);
 
-	return nft_trans_gc_alloc(gc->set, 0, gfp);
+	return nft_trans_gc_alloc(set, 0, gfp);
 }
 
 void nft_trans_gc_queue_sync_done(struct nft_trans_gc *trans)