[PATCH nf,v3] netfilter: nf_tables: remove catchall element in GC sync path

[Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>]

The expired catchall element is not removed from GC sync path. This path
holds mutex so just call nft_setelem_catchall_remove() before queueing
the GC work.

Fixes: 4a9e12ea7e70 ("netfilter: nft_set_pipapo: call nft_trans_gc_queue_sync() in catchall GC")
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
---
v3: add nft_setelem_catchall_destroy() and use it.

 net/netfilter/nf_tables_api.c | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 3c1fd8283bf4..8f6b455177f0 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -6520,6 +6520,12 @@ static int nft_setelem_deactivate(const struct net *net,
 	return ret;
 }
 
+static void nft_setelem_catchall_destroy(struct nft_set_elem_catchall *catchall)
+{
+	list_del_rcu(&catchall->list);
+	kfree_rcu(catchall, rcu);
+}
+
 static void nft_setelem_catchall_remove(const struct net *net,
 					const struct nft_set *set,
 					struct nft_elem_priv *elem_priv)
@@ -6528,8 +6534,7 @@ static void nft_setelem_catchall_remove(const struct net *net,
 
 	list_for_each_entry_safe(catchall, next, &set->catchall_list, list) {
 		if (catchall->elem == elem_priv) {
-			list_del_rcu(&catchall->list);
-			kfree_rcu(catchall, rcu);
+			nft_setelem_catchall_destroy(catchall);
 			break;
 		}
 	}
@@ -9678,11 +9683,11 @@ static struct nft_trans_gc *nft_trans_gc_catchall(struct nft_trans_gc *gc,
 						  unsigned int gc_seq,
 						  bool sync)
 {
-	struct nft_set_elem_catchall *catchall;
+	struct nft_set_elem_catchall *catchall, *next;
 	const struct nft_set *set = gc->set;
 	struct nft_set_ext *ext;
 
-	list_for_each_entry_rcu(catchall, &set->catchall_list, list) {
+	list_for_each_entry_safe(catchall, next, &set->catchall_list, list) {
 		ext = nft_set_elem_ext(set, catchall->elem);
 
 		if (!nft_set_elem_expired(ext))
@@ -9692,10 +9697,12 @@ static struct nft_trans_gc *nft_trans_gc_catchall(struct nft_trans_gc *gc,
 
 		nft_set_elem_dead(ext);
 dead_elem:
-		if (sync)
+		if (sync) {
+			nft_setelem_catchall_destroy(catchall);
 			gc = nft_trans_gc_queue_sync(gc, GFP_ATOMIC);
-		else
+		} else {
 			gc = nft_trans_gc_queue_async(gc, gc_seq, GFP_ATOMIC);
+		}
 
 		if (!gc)
 			return NULL;
-- 
2.30.2