[PATCH nf] netfilter: nft_set_rbtree: .deactivate fails if element has expired

[PATCH nf] netfilter: nft_set_rbtree: .deactivate fails if element has expired

[Pablo Neira Ayuso]

This allows to remove an expired element which is not possible in other
existing set backends, this is more noticeable if gc-interval is high so
expired elements remain in the tree. On-demand gc also does not help in
this case, because this is delete element path. Return NULL if element
has expired.

Fixes: 8d8540c4f5e0 ("netfilter: nft_set_rbtree: add timeout support")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/nft_set_rbtree.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/net/netfilter/nft_set_rbtree.c b/net/netfilter/nft_set_rbtree.c
index 2660ceab3759..e34662f4a71e 100644
--- a/net/netfilter/nft_set_rbtree.c
+++ b/net/netfilter/nft_set_rbtree.c
@@ -568,6 +568,8 @@ static void *nft_rbtree_deactivate(const struct net *net,
 				   nft_rbtree_interval_end(this)) {
 				parent = parent->rb_right;
 				continue;
+			} else if (nft_set_elem_expired(&rbe->ext)) {
+				break;
 			} else if (!nft_set_elem_active(&rbe->ext, genmask)) {
 				parent = parent->rb_left;
 				continue;
-- 
2.30.2