netfilter: Factor out the hook list selection from nf_register_hook
- Add a new function find_nf_hook_list to select the nf_hook_list
- Fail nf_register_hook when asked for a per netdevice hook list when
support for per netdevice hook lists is not built into the kernel.
- Move the hook list head selection outside of nf_hook_mutex as
nothing in the selection requires the hook list, and error handling
is simpler if a mutex is not held.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
diff --git a/net/netfilter/core.c b/net/netfilter/core.c
index c4c3b85..fa4d3c1 100644
--- a/net/netfilter/core.c
+++ b/net/netfilter/core.c
@@ -62,27 +62,31 @@
static DEFINE_MUTEX(nf_hook_mutex);
+static struct list_head *find_nf_hook_list(const struct nf_hook_ops *reg)
+{
+ struct list_head *nf_hook_list = NULL;
+
+ if (reg->pf != NFPROTO_NETDEV)
+ nf_hook_list = &nf_hooks[reg->pf][reg->hooknum];
+ else if (reg->hooknum == NF_NETDEV_INGRESS) {
+#ifdef CONFIG_NETFILTER_INGRESS
+ if (reg->dev)
+ nf_hook_list = ®->dev->nf_hooks_ingress;
+#endif
+ }
+ return nf_hook_list;
+}
+
int nf_register_hook(struct nf_hook_ops *reg)
{
struct list_head *nf_hook_list;
struct nf_hook_ops *elem;
- mutex_lock(&nf_hook_mutex);
- switch (reg->pf) {
- case NFPROTO_NETDEV:
-#ifdef CONFIG_NETFILTER_INGRESS
- if (reg->hooknum == NF_NETDEV_INGRESS) {
- BUG_ON(reg->dev == NULL);
- nf_hook_list = ®->dev->nf_hooks_ingress;
- break;
- }
-#endif
- /* Fall through. */
- default:
- nf_hook_list = &nf_hooks[reg->pf][reg->hooknum];
- break;
- }
+ nf_hook_list = find_nf_hook_list(reg);
+ if (!nf_hook_list)
+ return -ENOENT;
+ mutex_lock(&nf_hook_mutex);
list_for_each_entry(elem, nf_hook_list, list) {
if (reg->priority < elem->priority)
break;