Commit 2afd32b8 authored Jan 10, 2020 by Cong Wang Committed by Greg Kroah-Hartman Jan 23, 2020

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

commit c120959387efa51479056fd01dc90adfba7a590c upstream.

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: 40cd63bf ("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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 4a0a3385

net/netfilter/ipset/ip_set_bitmap_gen.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -66,9 +66,9 @@ 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;