netfilter: nft_set_rbtree: skip sync GC for new elements in this transaction

commit 2ee52ae94b upstream.

New elements in this transaction might expired before such transaction
ends. Skip sync GC for such elements otherwise commit path might walk
over an already released object. Once transaction is finished, async GC
will collect such expired element.

Fixes: f6c383b8c3 ("netfilter: nf_tables: adapt set backend to use GC transaction API")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Pablo Neira Ayuso 2023-09-22 18:43:08 +02:00 committed by Greg Kroah-Hartman
parent 9366966caf
commit 9af7dfb3c9

View file

@ -312,6 +312,7 @@ static int __nft_rbtree_insert(const struct net *net, const struct nft_set *set,
struct nft_rbtree_elem *rbe, *rbe_le = NULL, *rbe_ge = NULL;
struct rb_node *node, *next, *parent, **p, *first = NULL;
struct nft_rbtree *priv = nft_set_priv(set);
u8 cur_genmask = nft_genmask_cur(net);
u8 genmask = nft_genmask_next(net);
int d, err;
@ -357,8 +358,11 @@ static int __nft_rbtree_insert(const struct net *net, const struct nft_set *set,
if (!nft_set_elem_active(&rbe->ext, genmask))
continue;
/* perform garbage collection to avoid bogus overlap reports. */
if (nft_set_elem_expired(&rbe->ext)) {
/* perform garbage collection to avoid bogus overlap reports
* but skip new elements in this transaction.
*/
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;