From 9ea55b9f43533d30168aae0dfdc5c230b561ef69 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Mon, 30 May 2022 18:24:05 +0200 Subject: [PATCH] netfilter: nf_tables: hold mutex on netns pre_exit path commit 3923b1e4406680d57da7e873da77b1683035d83f upstream. clean_net() runs in workqueue while walking over the lists, grab mutex. Fixes: 767d1216bff8 ("netfilter: nftables: fix possible UAF over chains from packet path in netns") Signed-off-by: Pablo Neira Ayuso Signed-off-by: Greg Kroah-Hartman --- net/netfilter/nf_tables_api.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index ee4edebe6124..f274716e024d 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -9746,7 +9746,11 @@ static int __net_init nf_tables_init_net(struct net *net) static void __net_exit nf_tables_pre_exit_net(struct net *net) { + struct nftables_pernet *nft_net = nft_pernet(net); + + mutex_lock(&nft_net->commit_mutex); __nft_release_hooks(net); + mutex_unlock(&nft_net->commit_mutex); } static void __net_exit nf_tables_exit_net(struct net *net)