[PATCH 2/5] netns netfilter: per-netns xt_tables
In fact all we want is per-netns set of rules, however doing that will unnecessary complicate routines such as ipt_hook()/ipt_do_table, so make full xt_table array per-netns. Every user stubbed with init_net for a while. Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru> --- include/linux/netfilter/x_tables.h | 6 ++++-- include/net/net_namespace.h | 4 ++++ include/net/netns/x_tables.h | 10 ++++++++++ net/ipv4/netfilter/arp_tables.c | 12 ++++++------ net/ipv4/netfilter/ip_tables.c | 12 ++++++------ net/ipv6/netfilter/ip6_tables.c | 12 ++++++------ net/netfilter/x_tables.c | 35 ++++++++++++++++++++++++----------- 7 files changed, 60 insertions(+), 31 deletions(-) --- a/include/linux/netfilter/x_tables.h +++ b/include/linux/netfilter/x_tables.h @@ -335,7 +335,8 @@ extern int xt_check_target(const struct xt_target *target, unsigned short family unsigned int size, const char *table, unsigned int hook, unsigned short proto, int inv_proto); -extern struct xt_table *xt_register_table(struct xt_table *table, +extern struct xt_table *xt_register_table(struct net *net, + struct xt_table *table, struct xt_table_info *bootstrap, struct xt_table_info *newinfo); extern void *xt_unregister_table(struct xt_table *table); @@ -352,7 +353,8 @@ extern struct xt_target *xt_request_find_target(int af, const char *name, extern int xt_find_revision(int af, const char *name, u8 revision, int target, int *err); -extern struct xt_table *xt_find_table_lock(int af, const char *name); +extern struct xt_table *xt_find_table_lock(struct net *net, int af, + const char *name); extern void xt_table_unlock(struct xt_table *t); extern int xt_proto_init(int af); --- a/include/net/net_namespace.h +++ b/include/net/net_namespace.h @@ -12,6 +12,7 @@ #include <net/netns/packet.h> #include <net/netns/ipv4.h> #include <net/netns/ipv6.h> +#include <net/netns/x_tables.h> struct proc_dir_entry; struct net_device; @@ -56,6 +57,9 @@ struct net { #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) struct netns_ipv6 ipv6; #endif +#ifdef CONFIG_NETFILTER + struct netns_xt xt; +#endif }; #ifdef CONFIG_NET --- /dev/null +++ b/include/net/netns/x_tables.h @@ -0,0 +1,10 @@ +#ifndef __NETNS_X_TABLES_H +#define __NETNS_X_TABLES_H + +#include <linux/list.h> +#include <linux/net.h> + +struct netns_xt { + struct list_head tables[NPROTO]; +}; +#endif --- a/net/ipv4/netfilter/arp_tables.c +++ b/net/ipv4/netfilter/arp_tables.c @@ -870,7 +870,7 @@ static int get_info(void __user *user, int *len, int compat) if (compat) xt_compat_lock(NF_ARP); #endif - t = try_then_request_module(xt_find_table_lock(NF_ARP, name), + t = try_then_request_module(xt_find_table_lock(&init_net, NF_ARP, name), "arptable_%s", name); if (t && !IS_ERR(t)) { struct arpt_getinfo info; @@ -926,7 +926,7 @@ static int get_entries(struct arpt_get_entries __user *uptr, int *len) return -EINVAL; } - t = xt_find_table_lock(NF_ARP, get.name); + t = xt_find_table_lock(&init_net, NF_ARP, get.name); if (t && !IS_ERR(t)) { struct xt_table_info *private = t->private; duprintf("t->private->number = %u\n", @@ -966,7 +966,7 @@ static int __do_replace(const char *name, unsigned int valid_hooks, goto out; } - t = try_then_request_module(xt_find_table_lock(NF_ARP, name), + t = try_then_request_module(xt_find_table_lock(&init_net, NF_ARP, name), "arptable_%s", name); if (!t || IS_ERR(t)) { ret = t ? PTR_ERR(t) : -ENOENT; @@ -1132,7 +1132,7 @@ static int do_add_counters(void __user *user, unsigned int len, int compat) goto free; } - t = xt_find_table_lock(NF_ARP, name); + t = xt_find_table_lock(&init_net, NF_ARP, name); if (!t || IS_ERR(t)) { ret = t ? PTR_ERR(t) : -ENOENT; goto free; @@ -1604,7 +1604,7 @@ static int compat_get_entries(struct compat_arpt_get_entries __user *uptr, } xt_compat_lock(NF_ARP); - t = xt_find_table_lock(NF_ARP, get.name); + t = xt_find_table_lock(&init_net, NF_ARP, get.name); if (t && !IS_ERR(t)) { struct xt_table_info *private = t->private; struct xt_table_info info; @@ -1751,7 +1751,7 @@ int arpt_register_table(struct arpt_table *table, return ret; } - new_table = xt_register_table(table, &bootstrap, newinfo); + new_table = xt_register_table(&init_net, table, &bootstrap, newinfo); if (IS_ERR(new_table)) { xt_free_table_info(newinfo); return PTR_ERR(new_table); --- a/net/ipv4/netfilter/ip_tables.c +++ b/net/ipv4/netfilter/ip_tables.c @@ -1112,7 +1112,7 @@ static int get_info(void __user *user, int *len, int compat) if (compat) xt_compat_lock(AF_INET); #endif - t = try_then_request_module(xt_find_table_lock(AF_INET, name), + t = try_then_request_module(xt_find_table_lock(&init_net, AF_INET, name), "iptable_%s", name); if (t && !IS_ERR(t)) { struct ipt_getinfo info; @@ -1170,7 +1170,7 @@ get_entries(struct ipt_get_entries __user *uptr, int *len) return -EINVAL; } - t = xt_find_table_lock(AF_INET, get.name); + t = xt_find_table_lock(&init_net, AF_INET, get.name); if (t && !IS_ERR(t)) { struct xt_table_info *private = t->private; duprintf("t->private->number = %u\n", private->number); @@ -1208,7 +1208,7 @@ __do_replace(const char *name, unsigned int valid_hooks, goto out; } - t = try_then_request_module(xt_find_table_lock(AF_INET, name), + t = try_then_request_module(xt_find_table_lock(&init_net, AF_INET, name), "iptable_%s", name); if (!t || IS_ERR(t)) { ret = t ? PTR_ERR(t) : -ENOENT; @@ -1383,7 +1383,7 @@ do_add_counters(void __user *user, unsigned int len, int compat) goto free; } - t = xt_find_table_lock(AF_INET, name); + t = xt_find_table_lock(&init_net, AF_INET, name); if (!t || IS_ERR(t)) { ret = t ? PTR_ERR(t) : -ENOENT; goto free; @@ -1924,7 +1924,7 @@ compat_get_entries(struct compat_ipt_get_entries __user *uptr, int *len) } xt_compat_lock(AF_INET); - t = xt_find_table_lock(AF_INET, get.name); + t = xt_find_table_lock(&init_net, AF_INET, get.name); if (t && !IS_ERR(t)) { struct xt_table_info *private = t->private; struct xt_table_info info; @@ -2075,7 +2075,7 @@ int ipt_register_table(struct xt_table *table, const struct ipt_replace *repl) return ret; } - new_table = xt_register_table(table, &bootstrap, newinfo); + new_table = xt_register_table(&init_net, table, &bootstrap, newinfo); if (IS_ERR(new_table)) { xt_free_table_info(newinfo); return PTR_ERR(new_table); --- a/net/ipv6/netfilter/ip6_tables.c +++ b/net/ipv6/netfilter/ip6_tables.c @@ -1138,7 +1138,7 @@ static int get_info(void __user *user, int *len, int compat) if (compat) xt_compat_lock(AF_INET6); #endif - t = try_then_request_module(xt_find_table_lock(AF_INET6, name), + t = try_then_request_module(xt_find_table_lock(&init_net, AF_INET6, name), "ip6table_%s", name); if (t && !IS_ERR(t)) { struct ip6t_getinfo info; @@ -1196,7 +1196,7 @@ get_entries(struct ip6t_get_entries __user *uptr, int *len) return -EINVAL; } - t = xt_find_table_lock(AF_INET6, get.name); + t = xt_find_table_lock(&init_net, AF_INET6, get.name); if (t && !IS_ERR(t)) { struct xt_table_info *private = t->private; duprintf("t->private->number = %u\n", private->number); @@ -1235,7 +1235,7 @@ __do_replace(const char *name, unsigned int valid_hooks, goto out; } - t = try_then_request_module(xt_find_table_lock(AF_INET6, name), + t = try_then_request_module(xt_find_table_lock(&init_net, AF_INET6, name), "ip6table_%s", name); if (!t || IS_ERR(t)) { ret = t ? PTR_ERR(t) : -ENOENT; @@ -1410,7 +1410,7 @@ do_add_counters(void __user *user, unsigned int len, int compat) goto free; } - t = xt_find_table_lock(AF_INET6, name); + t = xt_find_table_lock(&init_net, AF_INET6, name); if (!t || IS_ERR(t)) { ret = t ? PTR_ERR(t) : -ENOENT; goto free; @@ -1950,7 +1950,7 @@ compat_get_entries(struct compat_ip6t_get_entries __user *uptr, int *len) } xt_compat_lock(AF_INET6); - t = xt_find_table_lock(AF_INET6, get.name); + t = xt_find_table_lock(&init_net, AF_INET6, get.name); if (t && !IS_ERR(t)) { struct xt_table_info *private = t->private; struct xt_table_info info; @@ -2101,7 +2101,7 @@ int ip6t_register_table(struct xt_table *table, const struct ip6t_replace *repl) return ret; } - new_table = xt_register_table(table, &bootstrap, newinfo); + new_table = xt_register_table(&init_net, table, &bootstrap, newinfo); if (IS_ERR(new_table)) { xt_free_table_info(newinfo); return PTR_ERR(new_table); --- a/net/netfilter/x_tables.c +++ b/net/netfilter/x_tables.c @@ -44,7 +44,6 @@ struct xt_af { struct mutex mutex; struct list_head match; struct list_head target; - struct list_head tables; #ifdef CONFIG_COMPAT struct mutex compat_mutex; struct compat_delta *compat_offsets; @@ -597,14 +596,14 @@ void xt_free_table_info(struct xt_table_info *info) EXPORT_SYMBOL(xt_free_table_info); /* Find table by name, grabs mutex & ref. Returns ERR_PTR() on error. */ -struct xt_table *xt_find_table_lock(int af, const char *name) +struct xt_table *xt_find_table_lock(struct net *net, int af, const char *name) { struct xt_table *t; if (mutex_lock_interruptible(&xt[af].mutex) != 0) return ERR_PTR(-EINTR); - list_for_each_entry(t, &xt[af].tables, list) + list_for_each_entry(t, &net->xt.tables[af], list) if (strcmp(t->name, name) == 0 && try_module_get(t->me)) return t; mutex_unlock(&xt[af].mutex); @@ -660,7 +659,7 @@ xt_replace_table(struct xt_table *table, } EXPORT_SYMBOL_GPL(xt_replace_table); -struct xt_table *xt_register_table(struct xt_table *table, +struct xt_table *xt_register_table(struct net *net, struct xt_table *table, struct xt_table_info *bootstrap, struct xt_table_info *newinfo) { @@ -673,7 +672,7 @@ struct xt_table *xt_register_table(struct xt_table *table, goto out; /* Don't autoload: we'd eat our tail... */ - list_for_each_entry(t, &xt[table->af].tables, list) { + list_for_each_entry(t, &net->xt.tables[table->af], list) { if (strcmp(t->name, table->name) == 0) { ret = -EEXIST; goto unlock; @@ -692,7 +691,7 @@ struct xt_table *xt_register_table(struct xt_table *table, /* save number of initial entries */ private->initial_entries = private->number; - list_add(&table->list, &xt[table->af].tables); + list_add(&table->list, &net->xt.tables[table->af]); mutex_unlock(&xt[table->af].mutex); return table; @@ -744,7 +743,7 @@ static struct list_head *type2list(u_int16_t af, u_int16_t type) list = &xt[af].match; break; case TABLE: - list = &xt[af].tables; + list = &init_net.xt.tables[af]; break; default: list = NULL; @@ -919,10 +918,22 @@ void xt_proto_fini(int af) } EXPORT_SYMBOL_GPL(xt_proto_fini); +static int __net_init xt_net_init(struct net *net) +{ + int i; + + for (i = 0; i < NPROTO; i++) + INIT_LIST_HEAD(&net->xt.tables[i]); + return 0; +} + +static struct pernet_operations xt_net_ops = { + .init = xt_net_init, +}; static int __init xt_init(void) { - int i; + int i, rv; xt = kmalloc(sizeof(struct xt_af) * NPROTO, GFP_KERNEL); if (!xt) @@ -936,13 +947,16 @@ static int __init xt_init(void) #endif INIT_LIST_HEAD(&xt[i].target); INIT_LIST_HEAD(&xt[i].match); - INIT_LIST_HEAD(&xt[i].tables); } - return 0; + rv = register_pernet_subsys(&xt_net_ops); + if (rv < 0) + kfree(xt); + return rv; } static void __exit xt_fini(void) { + unregister_pernet_subsys(&xt_net_ops); kfree(xt); }
Re: [PATCH 2/5] netns netfilter: per-netns xt_tables
Alexey Dobriyan wrote: > In fact all we want is per-netns set of rules, however doing that will > unnecessary complicate routines such as ipt_hook()/ipt_do_table, so > make full xt_table array per-netns. > > Every user stubbed with init_net for a while. Applied.