diff options
Diffstat (limited to 'net/netfilter/core.c')
| -rw-r--r-- | net/netfilter/core.c | 793 |
1 files changed, 793 insertions, 0 deletions
diff --git a/net/netfilter/core.c b/net/netfilter/core.c new file mode 100644 index 000000000..55a7f72d5 --- /dev/null +++ b/net/netfilter/core.c @@ -0,0 +1,793 @@ +/* netfilter.c: look after the filters for various protocols. + * Heavily influenced by the old firewall.c by David Bonn and Alan Cox. + * + * Thanks to Rob `CmdrTaco' Malda for not influencing this code in any + * way. + * + * This code is GPL. + */ +#include <linux/kernel.h> +#include <linux/netfilter.h> +#include <net/protocol.h> +#include <linux/init.h> +#include <linux/skbuff.h> +#include <linux/wait.h> +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/if.h> +#include <linux/netdevice.h> +#include <linux/netfilter_ipv6.h> +#include <linux/inetdevice.h> +#include <linux/proc_fs.h> +#include <linux/mutex.h> +#include <linux/mm.h> +#include <linux/rcupdate.h> +#include <net/net_namespace.h> +#include <net/netfilter/nf_queue.h> +#include <net/sock.h> + +#include "nf_internals.h" + +const struct nf_ipv6_ops __rcu *nf_ipv6_ops __read_mostly; +EXPORT_SYMBOL_GPL(nf_ipv6_ops); + +DEFINE_PER_CPU(bool, nf_skb_duplicated); +EXPORT_SYMBOL_GPL(nf_skb_duplicated); + +#ifdef CONFIG_JUMP_LABEL +struct static_key nf_hooks_needed[NFPROTO_NUMPROTO][NF_MAX_HOOKS]; +EXPORT_SYMBOL(nf_hooks_needed); +#endif + +static DEFINE_MUTEX(nf_hook_mutex); + +/* max hooks per family/hooknum */ +#define MAX_HOOK_COUNT 1024 + +#define nf_entry_dereference(e) \ + rcu_dereference_protected(e, lockdep_is_held(&nf_hook_mutex)) + +static struct nf_hook_entries *allocate_hook_entries_size(u16 num) +{ + struct nf_hook_entries *e; + size_t alloc = sizeof(*e) + + sizeof(struct nf_hook_entry) * num + + sizeof(struct nf_hook_ops *) * num + + sizeof(struct nf_hook_entries_rcu_head); + + if (num == 0) + return NULL; + + e = kvzalloc(alloc, GFP_KERNEL_ACCOUNT); + if (e) + e->num_hook_entries = num; + return e; +} + +static void __nf_hook_entries_free(struct rcu_head *h) +{ + struct nf_hook_entries_rcu_head *head; + + head = container_of(h, struct nf_hook_entries_rcu_head, head); + kvfree(head->allocation); +} + +static void nf_hook_entries_free(struct nf_hook_entries *e) +{ + struct nf_hook_entries_rcu_head *head; + struct nf_hook_ops **ops; + unsigned int num; + + if (!e) + return; + + num = e->num_hook_entries; + ops = nf_hook_entries_get_hook_ops(e); + head = (void *)&ops[num]; + head->allocation = e; + call_rcu(&head->head, __nf_hook_entries_free); +} + +static unsigned int accept_all(void *priv, + struct sk_buff *skb, + const struct nf_hook_state *state) +{ + return NF_ACCEPT; /* ACCEPT makes nf_hook_slow call next hook */ +} + +static const struct nf_hook_ops dummy_ops = { + .hook = accept_all, + .priority = INT_MIN, +}; + +static struct nf_hook_entries * +nf_hook_entries_grow(const struct nf_hook_entries *old, + const struct nf_hook_ops *reg) +{ + unsigned int i, alloc_entries, nhooks, old_entries; + struct nf_hook_ops **orig_ops = NULL; + struct nf_hook_ops **new_ops; + struct nf_hook_entries *new; + bool inserted = false; + + alloc_entries = 1; + old_entries = old ? old->num_hook_entries : 0; + + if (old) { + orig_ops = nf_hook_entries_get_hook_ops(old); + + for (i = 0; i < old_entries; i++) { + if (orig_ops[i] != &dummy_ops) + alloc_entries++; + } + } + + if (alloc_entries > MAX_HOOK_COUNT) + return ERR_PTR(-E2BIG); + + new = allocate_hook_entries_size(alloc_entries); + if (!new) + return ERR_PTR(-ENOMEM); + + new_ops = nf_hook_entries_get_hook_ops(new); + + i = 0; + nhooks = 0; + while (i < old_entries) { + if (orig_ops[i] == &dummy_ops) { + ++i; + continue; + } + + if (inserted || reg->priority > orig_ops[i]->priority) { + new_ops[nhooks] = (void *)orig_ops[i]; + new->hooks[nhooks] = old->hooks[i]; + i++; + } else { + new_ops[nhooks] = (void *)reg; + new->hooks[nhooks].hook = reg->hook; + new->hooks[nhooks].priv = reg->priv; + inserted = true; + } + nhooks++; + } + + if (!inserted) { + new_ops[nhooks] = (void *)reg; + new->hooks[nhooks].hook = reg->hook; + new->hooks[nhooks].priv = reg->priv; + } + + return new; +} + +static void hooks_validate(const struct nf_hook_entries *hooks) +{ +#ifdef CONFIG_DEBUG_MISC + struct nf_hook_ops **orig_ops; + int prio = INT_MIN; + size_t i = 0; + + orig_ops = nf_hook_entries_get_hook_ops(hooks); + + for (i = 0; i < hooks->num_hook_entries; i++) { + if (orig_ops[i] == &dummy_ops) + continue; + + WARN_ON(orig_ops[i]->priority < prio); + + if (orig_ops[i]->priority > prio) + prio = orig_ops[i]->priority; + } +#endif +} + +int nf_hook_entries_insert_raw(struct nf_hook_entries __rcu **pp, + const struct nf_hook_ops *reg) +{ + struct nf_hook_entries *new_hooks; + struct nf_hook_entries *p; + + p = rcu_dereference_raw(*pp); + new_hooks = nf_hook_entries_grow(p, reg); + if (IS_ERR(new_hooks)) + return PTR_ERR(new_hooks); + + hooks_validate(new_hooks); + + rcu_assign_pointer(*pp, new_hooks); + + BUG_ON(p == new_hooks); + nf_hook_entries_free(p); + return 0; +} +EXPORT_SYMBOL_GPL(nf_hook_entries_insert_raw); + +/* + * __nf_hook_entries_try_shrink - try to shrink hook array + * + * @old -- current hook blob at @pp + * @pp -- location of hook blob + * + * Hook unregistration must always succeed, so to-be-removed hooks + * are replaced by a dummy one that will just move to next hook. + * + * This counts the current dummy hooks, attempts to allocate new blob, + * copies the live hooks, then replaces and discards old one. + * + * return values: + * + * Returns address to free, or NULL. + */ +static void *__nf_hook_entries_try_shrink(struct nf_hook_entries *old, + struct nf_hook_entries __rcu **pp) +{ + unsigned int i, j, skip = 0, hook_entries; + struct nf_hook_entries *new = NULL; + struct nf_hook_ops **orig_ops; + struct nf_hook_ops **new_ops; + + if (WARN_ON_ONCE(!old)) + return NULL; + + orig_ops = nf_hook_entries_get_hook_ops(old); + for (i = 0; i < old->num_hook_entries; i++) { + if (orig_ops[i] == &dummy_ops) + skip++; + } + + /* if skip == hook_entries all hooks have been removed */ + hook_entries = old->num_hook_entries; + if (skip == hook_entries) + goto out_assign; + + if (skip == 0) + return NULL; + + hook_entries -= skip; + new = allocate_hook_entries_size(hook_entries); + if (!new) + return NULL; + + new_ops = nf_hook_entries_get_hook_ops(new); + for (i = 0, j = 0; i < old->num_hook_entries; i++) { + if (orig_ops[i] == &dummy_ops) + continue; + new->hooks[j] = old->hooks[i]; + new_ops[j] = (void *)orig_ops[i]; + j++; + } + hooks_validate(new); +out_assign: + rcu_assign_pointer(*pp, new); + return old; +} + +static struct nf_hook_entries __rcu ** +nf_hook_entry_head(struct net *net, int pf, unsigned int hooknum, + struct net_device *dev) +{ + switch (pf) { + case NFPROTO_NETDEV: + break; +#ifdef CONFIG_NETFILTER_FAMILY_ARP + case NFPROTO_ARP: + if (WARN_ON_ONCE(ARRAY_SIZE(net->nf.hooks_arp) <= hooknum)) + return NULL; + return net->nf.hooks_arp + hooknum; +#endif +#ifdef CONFIG_NETFILTER_FAMILY_BRIDGE + case NFPROTO_BRIDGE: + if (WARN_ON_ONCE(ARRAY_SIZE(net->nf.hooks_bridge) <= hooknum)) + return NULL; + return net->nf.hooks_bridge + hooknum; +#endif +#ifdef CONFIG_NETFILTER_INGRESS + case NFPROTO_INET: + if (WARN_ON_ONCE(hooknum != NF_INET_INGRESS)) + return NULL; + if (!dev || dev_net(dev) != net) { + WARN_ON_ONCE(1); + return NULL; + } + return &dev->nf_hooks_ingress; +#endif + case NFPROTO_IPV4: + if (WARN_ON_ONCE(ARRAY_SIZE(net->nf.hooks_ipv4) <= hooknum)) + return NULL; + return net->nf.hooks_ipv4 + hooknum; + case NFPROTO_IPV6: + if (WARN_ON_ONCE(ARRAY_SIZE(net->nf.hooks_ipv6) <= hooknum)) + return NULL; + return net->nf.hooks_ipv6 + hooknum; + default: + WARN_ON_ONCE(1); + return NULL; + } + +#ifdef CONFIG_NETFILTER_INGRESS + if (hooknum == NF_NETDEV_INGRESS) { + if (dev && dev_net(dev) == net) + return &dev->nf_hooks_ingress; + } +#endif +#ifdef CONFIG_NETFILTER_EGRESS + if (hooknum == NF_NETDEV_EGRESS) { + if (dev && dev_net(dev) == net) + return &dev->nf_hooks_egress; + } +#endif + WARN_ON_ONCE(1); + return NULL; +} + +static int nf_ingress_check(struct net *net, const struct nf_hook_ops *reg, + int hooknum) +{ +#ifndef CONFIG_NETFILTER_INGRESS + if (reg->hooknum == hooknum) + return -EOPNOTSUPP; +#endif + if (reg->hooknum != hooknum || + !reg->dev || dev_net(reg->dev) != net) + return -EINVAL; + + return 0; +} + +static inline bool __maybe_unused nf_ingress_hook(const struct nf_hook_ops *reg, + int pf) +{ + if ((pf == NFPROTO_NETDEV && reg->hooknum == NF_NETDEV_INGRESS) || + (pf == NFPROTO_INET && reg->hooknum == NF_INET_INGRESS)) + return true; + + return false; +} + +static inline bool __maybe_unused nf_egress_hook(const struct nf_hook_ops *reg, + int pf) +{ + return pf == NFPROTO_NETDEV && reg->hooknum == NF_NETDEV_EGRESS; +} + +static void nf_static_key_inc(const struct nf_hook_ops *reg, int pf) +{ +#ifdef CONFIG_JUMP_LABEL + int hooknum; + + if (pf == NFPROTO_INET && reg->hooknum == NF_INET_INGRESS) { + pf = NFPROTO_NETDEV; + hooknum = NF_NETDEV_INGRESS; + } else { + hooknum = reg->hooknum; + } + static_key_slow_inc(&nf_hooks_needed[pf][hooknum]); +#endif +} + +static void nf_static_key_dec(const struct nf_hook_ops *reg, int pf) +{ +#ifdef CONFIG_JUMP_LABEL + int hooknum; + + if (pf == NFPROTO_INET && reg->hooknum == NF_INET_INGRESS) { + pf = NFPROTO_NETDEV; + hooknum = NF_NETDEV_INGRESS; + } else { + hooknum = reg->hooknum; + } + static_key_slow_dec(&nf_hooks_needed[pf][hooknum]); +#endif +} + +static int __nf_register_net_hook(struct net *net, int pf, + const struct nf_hook_ops *reg) +{ + struct nf_hook_entries *p, *new_hooks; + struct nf_hook_entries __rcu **pp; + int err; + + switch (pf) { + case NFPROTO_NETDEV: +#ifndef CONFIG_NETFILTER_INGRESS + if (reg->hooknum == NF_NETDEV_INGRESS) + return -EOPNOTSUPP; +#endif +#ifndef CONFIG_NETFILTER_EGRESS + if (reg->hooknum == NF_NETDEV_EGRESS) + return -EOPNOTSUPP; +#endif + if ((reg->hooknum != NF_NETDEV_INGRESS && + reg->hooknum != NF_NETDEV_EGRESS) || + !reg->dev || dev_net(reg->dev) != net) + return -EINVAL; + break; + case NFPROTO_INET: + if (reg->hooknum != NF_INET_INGRESS) + break; + + err = nf_ingress_check(net, reg, NF_INET_INGRESS); + if (err < 0) + return err; + break; + } + + pp = nf_hook_entry_head(net, pf, reg->hooknum, reg->dev); + if (!pp) + return -EINVAL; + + mutex_lock(&nf_hook_mutex); + + p = nf_entry_dereference(*pp); + new_hooks = nf_hook_entries_grow(p, reg); + + if (!IS_ERR(new_hooks)) { + hooks_validate(new_hooks); + rcu_assign_pointer(*pp, new_hooks); + } + + mutex_unlock(&nf_hook_mutex); + if (IS_ERR(new_hooks)) + return PTR_ERR(new_hooks); + +#ifdef CONFIG_NETFILTER_INGRESS + if (nf_ingress_hook(reg, pf)) + net_inc_ingress_queue(); +#endif +#ifdef CONFIG_NETFILTER_EGRESS + if (nf_egress_hook(reg, pf)) + net_inc_egress_queue(); +#endif + nf_static_key_inc(reg, pf); + + BUG_ON(p == new_hooks); + nf_hook_entries_free(p); + return 0; +} + +/* + * nf_remove_net_hook - remove a hook from blob + * + * @oldp: current address of hook blob + * @unreg: hook to unregister + * + * This cannot fail, hook unregistration must always succeed. + * Therefore replace the to-be-removed hook with a dummy hook. + */ +static bool nf_remove_net_hook(struct nf_hook_entries *old, + const struct nf_hook_ops *unreg) +{ + struct nf_hook_ops **orig_ops; + unsigned int i; + + orig_ops = nf_hook_entries_get_hook_ops(old); + for (i = 0; i < old->num_hook_entries; i++) { + if (orig_ops[i] != unreg) + continue; + WRITE_ONCE(old->hooks[i].hook, accept_all); + WRITE_ONCE(orig_ops[i], (void *)&dummy_ops); + return true; + } + + return false; +} + +static void __nf_unregister_net_hook(struct net *net, int pf, + const struct nf_hook_ops *reg) +{ + struct nf_hook_entries __rcu **pp; + struct nf_hook_entries *p; + + pp = nf_hook_entry_head(net, pf, reg->hooknum, reg->dev); + if (!pp) + return; + + mutex_lock(&nf_hook_mutex); + + p = nf_entry_dereference(*pp); + if (WARN_ON_ONCE(!p)) { + mutex_unlock(&nf_hook_mutex); + return; + } + + if (nf_remove_net_hook(p, reg)) { +#ifdef CONFIG_NETFILTER_INGRESS + if (nf_ingress_hook(reg, pf)) + net_dec_ingress_queue(); +#endif +#ifdef CONFIG_NETFILTER_EGRESS + if (nf_egress_hook(reg, pf)) + net_dec_egress_queue(); +#endif + nf_static_key_dec(reg, pf); + } else { + WARN_ONCE(1, "hook not found, pf %d num %d", pf, reg->hooknum); + } + + p = __nf_hook_entries_try_shrink(p, pp); + mutex_unlock(&nf_hook_mutex); + if (!p) + return; + + nf_queue_nf_hook_drop(net); + nf_hook_entries_free(p); +} + +void nf_unregister_net_hook(struct net *net, const struct nf_hook_ops *reg) +{ + if (reg->pf == NFPROTO_INET) { + if (reg->hooknum == NF_INET_INGRESS) { + __nf_unregister_net_hook(net, NFPROTO_INET, reg); + } else { + __nf_unregister_net_hook(net, NFPROTO_IPV4, reg); + __nf_unregister_net_hook(net, NFPROTO_IPV6, reg); + } + } else { + __nf_unregister_net_hook(net, reg->pf, reg); + } +} +EXPORT_SYMBOL(nf_unregister_net_hook); + +void nf_hook_entries_delete_raw(struct nf_hook_entries __rcu **pp, + const struct nf_hook_ops *reg) +{ + struct nf_hook_entries *p; + + p = rcu_dereference_raw(*pp); + if (nf_remove_net_hook(p, reg)) { + p = __nf_hook_entries_try_shrink(p, pp); + nf_hook_entries_free(p); + } +} +EXPORT_SYMBOL_GPL(nf_hook_entries_delete_raw); + +int nf_register_net_hook(struct net *net, const struct nf_hook_ops *reg) +{ + int err; + + if (reg->pf == NFPROTO_INET) { + if (reg->hooknum == NF_INET_INGRESS) { + err = __nf_register_net_hook(net, NFPROTO_INET, reg); + if (err < 0) + return err; + } else { + err = __nf_register_net_hook(net, NFPROTO_IPV4, reg); + if (err < 0) + return err; + + err = __nf_register_net_hook(net, NFPROTO_IPV6, reg); + if (err < 0) { + __nf_unregister_net_hook(net, NFPROTO_IPV4, reg); + return err; + } + } + } else { + err = __nf_register_net_hook(net, reg->pf, reg); + if (err < 0) + return err; + } + + return 0; +} +EXPORT_SYMBOL(nf_register_net_hook); + +int nf_register_net_hooks(struct net *net, const struct nf_hook_ops *reg, + unsigned int n) +{ + unsigned int i; + int err = 0; + + for (i = 0; i < n; i++) { + err = nf_register_net_hook(net, ®[i]); + if (err) + goto err; + } + return err; + +err: + if (i > 0) + nf_unregister_net_hooks(net, reg, i); + return err; +} +EXPORT_SYMBOL(nf_register_net_hooks); + +void nf_unregister_net_hooks(struct net *net, const struct nf_hook_ops *reg, + unsigned int hookcount) +{ + unsigned int i; + + for (i = 0; i < hookcount; i++) + nf_unregister_net_hook(net, ®[i]); +} +EXPORT_SYMBOL(nf_unregister_net_hooks); + +/* Returns 1 if okfn() needs to be executed by the caller, + * -EPERM for NF_DROP, 0 otherwise. Caller must hold rcu_read_lock. */ +int nf_hook_slow(struct sk_buff *skb, struct nf_hook_state *state, + const struct nf_hook_entries *e, unsigned int s) +{ + unsigned int verdict; + int ret; + + for (; s < e->num_hook_entries; s++) { + verdict = nf_hook_entry_hookfn(&e->hooks[s], skb, state); + switch (verdict & NF_VERDICT_MASK) { + case NF_ACCEPT: + break; + case NF_DROP: + kfree_skb_reason(skb, + SKB_DROP_REASON_NETFILTER_DROP); + ret = NF_DROP_GETERR(verdict); + if (ret == 0) + ret = -EPERM; + return ret; + case NF_QUEUE: + ret = nf_queue(skb, state, s, verdict); + if (ret == 1) + continue; + return ret; + default: + /* Implicit handling for NF_STOLEN, as well as any other + * non conventional verdicts. + */ + return 0; + } + } + + return 1; +} +EXPORT_SYMBOL(nf_hook_slow); + +void nf_hook_slow_list(struct list_head *head, struct nf_hook_state *state, + const struct nf_hook_entries *e) +{ + struct sk_buff *skb, *next; + struct list_head sublist; + int ret; + + INIT_LIST_HEAD(&sublist); + + list_for_each_entry_safe(skb, next, head, list) { + skb_list_del_init(skb); + ret = nf_hook_slow(skb, state, e, 0); + if (ret == 1) + list_add_tail(&skb->list, &sublist); + } + /* Put passed packets back on main list */ + list_splice(&sublist, head); +} +EXPORT_SYMBOL(nf_hook_slow_list); + +/* This needs to be compiled in any case to avoid dependencies between the + * nfnetlink_queue code and nf_conntrack. + */ +const struct nfnl_ct_hook __rcu *nfnl_ct_hook __read_mostly; +EXPORT_SYMBOL_GPL(nfnl_ct_hook); + +const struct nf_ct_hook __rcu *nf_ct_hook __read_mostly; +EXPORT_SYMBOL_GPL(nf_ct_hook); + +#if IS_ENABLED(CONFIG_NF_CONNTRACK) +u8 nf_ctnetlink_has_listener; +EXPORT_SYMBOL_GPL(nf_ctnetlink_has_listener); + +const struct nf_nat_hook __rcu *nf_nat_hook __read_mostly; +EXPORT_SYMBOL_GPL(nf_nat_hook); + +/* This does not belong here, but locally generated errors need it if connection + * tracking in use: without this, connection may not be in hash table, and hence + * manufactured ICMP or RST packets will not be associated with it. + */ +void nf_ct_attach(struct sk_buff *new, const struct sk_buff *skb) +{ + const struct nf_ct_hook *ct_hook; + + if (skb->_nfct) { + rcu_read_lock(); + ct_hook = rcu_dereference(nf_ct_hook); + if (ct_hook) + ct_hook->attach(new, skb); + rcu_read_unlock(); + } +} +EXPORT_SYMBOL(nf_ct_attach); + +void nf_conntrack_destroy(struct nf_conntrack *nfct) +{ + const struct nf_ct_hook *ct_hook; + + rcu_read_lock(); + ct_hook = rcu_dereference(nf_ct_hook); + if (ct_hook) + ct_hook->destroy(nfct); + rcu_read_unlock(); + + WARN_ON(!ct_hook); +} +EXPORT_SYMBOL(nf_conntrack_destroy); + +bool nf_ct_get_tuple_skb(struct nf_conntrack_tuple *dst_tuple, + const struct sk_buff *skb) +{ + const struct nf_ct_hook *ct_hook; + bool ret = false; + + rcu_read_lock(); + ct_hook = rcu_dereference(nf_ct_hook); + if (ct_hook) + ret = ct_hook->get_tuple_skb(dst_tuple, skb); + rcu_read_unlock(); + return ret; +} +EXPORT_SYMBOL(nf_ct_get_tuple_skb); + +/* Built-in default zone used e.g. by modules. */ +const struct nf_conntrack_zone nf_ct_zone_dflt = { + .id = NF_CT_DEFAULT_ZONE_ID, + .dir = NF_CT_DEFAULT_ZONE_DIR, +}; +EXPORT_SYMBOL_GPL(nf_ct_zone_dflt); +#endif /* CONFIG_NF_CONNTRACK */ + +static void __net_init +__netfilter_net_init(struct nf_hook_entries __rcu **e, int max) +{ + int h; + + for (h = 0; h < max; h++) + RCU_INIT_POINTER(e[h], NULL); +} + +static int __net_init netfilter_net_init(struct net *net) +{ + __netfilter_net_init(net->nf.hooks_ipv4, ARRAY_SIZE(net->nf.hooks_ipv4)); + __netfilter_net_init(net->nf.hooks_ipv6, ARRAY_SIZE(net->nf.hooks_ipv6)); +#ifdef CONFIG_NETFILTER_FAMILY_ARP + __netfilter_net_init(net->nf.hooks_arp, ARRAY_SIZE(net->nf.hooks_arp)); +#endif +#ifdef CONFIG_NETFILTER_FAMILY_BRIDGE + __netfilter_net_init(net->nf.hooks_bridge, ARRAY_SIZE(net->nf.hooks_bridge)); +#endif +#ifdef CONFIG_PROC_FS + net->nf.proc_netfilter = proc_net_mkdir(net, "netfilter", + net->proc_net); + if (!net->nf.proc_netfilter) { + if (!net_eq(net, &init_net)) + pr_err("cannot create netfilter proc entry"); + + return -ENOMEM; + } +#endif + + return 0; +} + +static void __net_exit netfilter_net_exit(struct net *net) +{ + remove_proc_entry("netfilter", net->proc_net); +} + +static struct pernet_operations netfilter_net_ops = { + .init = netfilter_net_init, + .exit = netfilter_net_exit, +}; + +int __init netfilter_init(void) +{ + int ret; + + ret = register_pernet_subsys(&netfilter_net_ops); + if (ret < 0) + goto err; + + ret = netfilter_log_init(); + if (ret < 0) + goto err_pernet; + + return 0; +err_pernet: + unregister_pernet_subsys(&netfilter_net_ops); +err: + return ret; +} |