From 14e567615679a9999ce6bf4f23d6c9e00f03e00e Mon Sep 17 00:00:00 2001 From: Liping Zhang Date: Mon, 17 Apr 2017 21:18:55 +0800 Subject: [PATCH] netfilter: ctnetlink: drop the incorrect cthelper module request First, when creating a new ct, we will invoke request_module to try to load the related inkernel cthelper. So there's no need to call the request_module again when updating the ct helpinfo. Second, ctnetlink_change_helper may be called with rcu_read_lock held, i.e. rcu_read_lock -> nfqnl_recv_verdict -> nfqnl_ct_parse -> ctnetlink_glue_parse -> ctnetlink_glue_parse_ct -> ctnetlink_change_helper. But the request_module invocation may sleep, so we can't call it with the rcu_read_lock held. Remove it now. Signed-off-by: Liping Zhang Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_conntrack_netlink.c | 17 +---------------- 1 file changed, 1 insertion(+), 16 deletions(-) diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c index dc7dfd6..48c1845 100644 --- a/net/netfilter/nf_conntrack_netlink.c +++ b/net/netfilter/nf_conntrack_netlink.c @@ -1512,23 +1512,8 @@ static int ctnetlink_change_helper(struct nf_conn *ct, helper = __nf_conntrack_helper_find(helpname, nf_ct_l3num(ct), nf_ct_protonum(ct)); - if (helper == NULL) { -#ifdef CONFIG_MODULES - spin_unlock_bh(&nf_conntrack_expect_lock); - - if (request_module("nfct-helper-%s", helpname) < 0) { - spin_lock_bh(&nf_conntrack_expect_lock); - return -EOPNOTSUPP; - } - - spin_lock_bh(&nf_conntrack_expect_lock); - helper = __nf_conntrack_helper_find(helpname, nf_ct_l3num(ct), - nf_ct_protonum(ct)); - if (helper) - return -EAGAIN; -#endif + if (helper == NULL) return -EOPNOTSUPP; - } if (help) { if (help->helper == helper) { -- 2.7.4