1 files changed, 32 insertions, 22 deletions

diff --git a/net/netfilter/nft_set_rbtree.c b/net/netfilter/nft_set_rbtree.c
index f250b5399344..2660ceab3759 100644
--- a/net/netfilter/nft_set_rbtree.c
+++ b/net/netfilter/nft_set_rbtree.c
@@ -233,10 +233,9 @@ static void nft_rbtree_gc_remove(struct net *net, struct nft_set *set,
 	rb_erase(&rbe->node, &priv->root);
 }
 
-static int nft_rbtree_gc_elem(const struct nft_set *__set,
-			      struct nft_rbtree *priv,
-			      struct nft_rbtree_elem *rbe,
-			      u8 genmask)
+static const struct nft_rbtree_elem *
+nft_rbtree_gc_elem(const struct nft_set *__set, struct nft_rbtree *priv,
+		   struct nft_rbtree_elem *rbe, u8 genmask)
 {
 	struct nft_set *set = (struct nft_set *)__set;
 	struct rb_node *prev = rb_prev(&rbe->node);
@@ -246,7 +245,7 @@ static int nft_rbtree_gc_elem(const struct nft_set *__set,
 
 	gc = nft_trans_gc_alloc(set, 0, GFP_ATOMIC);
 	if (!gc)
-		return -ENOMEM;
+		return ERR_PTR(-ENOMEM);
 
 	/* search for end interval coming before this element.
 	 * end intervals don't carry a timeout extension, they
@@ -261,6 +260,7 @@ static int nft_rbtree_gc_elem(const struct nft_set *__set,
 		prev = rb_prev(prev);
 	}
 
+	rbe_prev = NULL;
 	if (prev) {
 		rbe_prev = rb_entry(prev, struct nft_rbtree_elem, node);
 		nft_rbtree_gc_remove(net, set, priv, rbe_prev);
@@ -272,7 +272,7 @@ static int nft_rbtree_gc_elem(const struct nft_set *__set,
 		 */
 		gc = nft_trans_gc_queue_sync(gc, GFP_ATOMIC);
 		if (WARN_ON_ONCE(!gc))
-			return -ENOMEM;
+			return ERR_PTR(-ENOMEM);
 
 		nft_trans_gc_elem_add(gc, rbe_prev);
 	}
@@ -280,13 +280,13 @@ static int nft_rbtree_gc_elem(const struct nft_set *__set,
 	nft_rbtree_gc_remove(net, set, priv, rbe);
 	gc = nft_trans_gc_queue_sync(gc, GFP_ATOMIC);
 	if (WARN_ON_ONCE(!gc))
-		return -ENOMEM;
+		return ERR_PTR(-ENOMEM);
 
 	nft_trans_gc_elem_add(gc, rbe);
 
 	nft_trans_gc_queue_sync_done(gc);
 
-	return 0;
+	return rbe_prev;
 }
 
 static bool nft_rbtree_update_first(const struct nft_set *set,
@@ -314,7 +314,7 @@ static int __nft_rbtree_insert(const struct net *net, const struct nft_set *set,
 	struct nft_rbtree *priv = nft_set_priv(set);
 	u8 cur_genmask = nft_genmask_cur(net);
 	u8 genmask = nft_genmask_next(net);
-	int d, err;
+	int d;
 
 	/* Descend the tree to search for an existing element greater than the
 	 * key value to insert that is greater than the new element. This is the
@@ -363,9 +363,14 @@ static int __nft_rbtree_insert(const struct net *net, const struct nft_set *set,
 		 */
 		if (nft_set_elem_expired(&rbe->ext) &&
 		    nft_set_elem_active(&rbe->ext, cur_genmask)) {
-			err = nft_rbtree_gc_elem(set, priv, rbe, genmask);
-			if (err < 0)
-				return err;
+			const struct nft_rbtree_elem *removed_end;
+
+			removed_end = nft_rbtree_gc_elem(set, priv, rbe, genmask);
+			if (IS_ERR(removed_end))
+				return PTR_ERR(removed_end);
+
+			if (removed_end == rbe_le || removed_end == rbe_ge)
+				return -EAGAIN;
 
 			continue;
 		}
@@ -486,11 +491,18 @@ static int nft_rbtree_insert(const struct net *net, const struct nft_set *set,
 	struct nft_rbtree_elem *rbe = elem->priv;
 	int err;
 
-	write_lock_bh(&priv->lock);
-	write_seqcount_begin(&priv->count);
-	err = __nft_rbtree_insert(net, set, rbe, ext);
-	write_seqcount_end(&priv->count);
-	write_unlock_bh(&priv->lock);
+	do {
+		if (fatal_signal_pending(current))
+			return -EINTR;
+
+		cond_resched();
+
+		write_lock_bh(&priv->lock);
+		write_seqcount_begin(&priv->count);
+		err = __nft_rbtree_insert(net, set, rbe, ext);
+		write_seqcount_end(&priv->count);
+		write_unlock_bh(&priv->lock);
+	} while (err == -EAGAIN);
 
 	return err;
 }
@@ -622,8 +634,7 @@ static void nft_rbtree_gc(struct work_struct *work)
 	if (!gc)
 		goto done;
 
-	write_lock_bh(&priv->lock);
-	write_seqcount_begin(&priv->count);
+	read_lock_bh(&priv->lock);
 	for (node = rb_first(&priv->root); node != NULL; node = rb_next(node)) {
 
 		/* Ruleset has been updated, try later. */
@@ -670,11 +681,10 @@ dead_elem:
 		nft_trans_gc_elem_add(gc, rbe);
 	}
 
-	gc = nft_trans_gc_catchall(gc, gc_seq);
+	gc = nft_trans_gc_catchall_async(gc, gc_seq);
 
 try_later:
-	write_seqcount_end(&priv->count);
-	write_unlock_bh(&priv->lock);
+	read_unlock_bh(&priv->lock);
 
 	if (gc)
 		nft_trans_gc_queue_async_done(gc);