netfilter: fix a use-after-free in mtype_destroy()

map->members is freed by ip_set_free() right before using it in
mtype_ext_cleanup() again. So we just have to move it down.

Reported-by: syzbot+4c3cc6dbe7259dbf9054@syzkaller.appspotmail.com
Fixes: 40cd63bf33 ("netfilter: ipset: Support extensions which need a per data destroy function")
Acked-by: Jozsef Kadlecsik <kadlec@netfilter.org>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Cong Wang 2020-01-10 11:53:08 -08:00 committed by Pablo Neira Ayuso
parent c9f53049d4
commit c120959387

View File

@ -60,9 +60,9 @@ mtype_destroy(struct ip_set *set)
if (SET_WITH_TIMEOUT(set))
del_timer_sync(&map->gc);
ip_set_free(map->members);
if (set->dsize && set->extensions & IPSET_EXT_DESTROY)
mtype_ext_cleanup(set);
ip_set_free(map->members);
ip_set_free(map);
set->data = NULL;