netfilter: ctnetlink: fix scheduling while atomic if helper is autoloaded
This patch fixes one scheduling while atomic error:
[ 385.565186] ctnetlink v0.93: registering with nfnetlink.
[ 385.565349] BUG: scheduling while atomic: lt-expect_creat/16163/0x00000200
It can be triggered with utils/expect_create included in
libnetfilter_conntrack if the FTP helper is not loaded.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
index 3d7ea7a..b697777 100644
--- a/net/netfilter/nf_conntrack_netlink.c
+++ b/net/netfilter/nf_conntrack_netlink.c
@@ -1358,12 +1358,15 @@
nf_ct_protonum(ct));
if (helper == NULL) {
rcu_read_unlock();
+ spin_unlock_bh(&nf_conntrack_lock);
#ifdef CONFIG_MODULES
if (request_module("nfct-helper-%s", helpname) < 0) {
+ spin_lock_bh(&nf_conntrack_lock);
err = -EOPNOTSUPP;
goto err1;
}
+ spin_lock_bh(&nf_conntrack_lock);
rcu_read_lock();
helper = __nf_conntrack_helper_find(helpname,
nf_ct_l3num(ct),