[mirror_ubuntu-bionic-kernel.git] / net / core / sysctl_net_core.c

/* -*- linux-c -*-
 * sysctl_net_core.c: sysctl interface to net core subsystem.
 *
 * Begun April 1, 1996, Mike Shaver.
 * Added /proc/sys/net/core directory entry (empty =) ). [MS]
 */

#include <linux/mm.h>
#include <linux/sysctl.h>
#include <linux/module.h>
#include <linux/socket.h>
#include <linux/netdevice.h>
#include <linux/ratelimit.h>
#include <linux/vmalloc.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/kmemleak.h>

#include <net/ip.h>
#include <net/sock.h>
#include <net/net_ratelimit.h>
#include <net/ll_poll.h>

static int one = 1;

#ifdef CONFIG_RPS
static int rps_sock_flow_sysctl(struct ctl_table *table, int write,
				void __user *buffer, size_t *lenp, loff_t *ppos)
{
	unsigned int orig_size, size;
	int ret, i;
	struct ctl_table tmp = {
		.data = &size,
		.maxlen = sizeof(size),
		.mode = table->mode
	};
	struct rps_sock_flow_table *orig_sock_table, *sock_table;
	static DEFINE_MUTEX(sock_flow_mutex);

	mutex_lock(&sock_flow_mutex);

	orig_sock_table = rcu_dereference_protected(rps_sock_flow_table,
					lockdep_is_held(&sock_flow_mutex));
	size = orig_size = orig_sock_table ? orig_sock_table->mask + 1 : 0;

	ret = proc_dointvec(&tmp, write, buffer, lenp, ppos);

	if (write) {
		if (size) {
			if (size > 1<<30) {
				/* Enforce limit to prevent overflow */
				mutex_unlock(&sock_flow_mutex);
				return -EINVAL;
			}
			size = roundup_pow_of_two(size);
			if (size != orig_size) {
				sock_table =
				    vmalloc(RPS_SOCK_FLOW_TABLE_SIZE(size));
				if (!sock_table) {
					mutex_unlock(&sock_flow_mutex);
					return -ENOMEM;
				}

				sock_table->mask = size - 1;
			} else
				sock_table = orig_sock_table;

			for (i = 0; i < size; i++)
				sock_table->ents[i] = RPS_NO_CPU;
		} else
			sock_table = NULL;

		if (sock_table != orig_sock_table) {
			rcu_assign_pointer(rps_sock_flow_table, sock_table);
			if (sock_table)
				static_key_slow_inc(&rps_needed);
			if (orig_sock_table) {
				static_key_slow_dec(&rps_needed);
				synchronize_rcu();
				vfree(orig_sock_table);
			}
		}
	}

	mutex_unlock(&sock_flow_mutex);

	return ret;
}
#endif /* CONFIG_RPS */

#ifdef CONFIG_NET_FLOW_LIMIT
static DEFINE_MUTEX(flow_limit_update_mutex);

static int flow_limit_cpu_sysctl(struct ctl_table *table, int write,
				 void __user *buffer, size_t *lenp,
				 loff_t *ppos)
{
	struct sd_flow_limit *cur;
	struct softnet_data *sd;
	cpumask_var_t mask;
	int i, len, ret = 0;

	if (!alloc_cpumask_var(&mask, GFP_KERNEL))
		return -ENOMEM;

	if (write) {
		ret = cpumask_parse_user(buffer, *lenp, mask);
		if (ret)
			goto done;

		mutex_lock(&flow_limit_update_mutex);
		len = sizeof(*cur) + netdev_flow_limit_table_len;
		for_each_possible_cpu(i) {
			sd = &per_cpu(softnet_data, i);
			cur = rcu_dereference_protected(sd->flow_limit,
				     lockdep_is_held(&flow_limit_update_mutex));
			if (cur && !cpumask_test_cpu(i, mask)) {
				RCU_INIT_POINTER(sd->flow_limit, NULL);
				synchronize_rcu();
				kfree(cur);
			} else if (!cur && cpumask_test_cpu(i, mask)) {
				cur = kzalloc(len, GFP_KERNEL);
				if (!cur) {
					/* not unwinding previous changes */
					ret = -ENOMEM;
					goto write_unlock;
				}
				cur->num_buckets = netdev_flow_limit_table_len;
				rcu_assign_pointer(sd->flow_limit, cur);
			}
		}
write_unlock:
		mutex_unlock(&flow_limit_update_mutex);
	} else {
		if (*ppos || !*lenp) {
			*lenp = 0;
			goto done;
		}

		cpumask_clear(mask);
		rcu_read_lock();
		for_each_possible_cpu(i) {
			sd = &per_cpu(softnet_data, i);
			if (rcu_dereference(sd->flow_limit))
				cpumask_set_cpu(i, mask);
		}
		rcu_read_unlock();

		len = cpumask_scnprintf(buffer, *lenp, mask);
		*lenp = len + 1;
		*ppos += len + 1;
	}

done:
	free_cpumask_var(mask);
	return ret;
}

static int flow_limit_table_len_sysctl(struct ctl_table *table, int write,
				       void __user *buffer, size_t *lenp,
				       loff_t *ppos)
{
	unsigned int old, *ptr;
	int ret;

	mutex_lock(&flow_limit_update_mutex);

	ptr = table->data;
	old = *ptr;
	ret = proc_dointvec(table, write, buffer, lenp, ppos);
	if (!ret && write && !is_power_of_2(*ptr)) {
		*ptr = old;
		ret = -EINVAL;
	}

	mutex_unlock(&flow_limit_update_mutex);
	return ret;
}
#endif /* CONFIG_NET_FLOW_LIMIT */

static struct ctl_table net_core_table[] = {
#ifdef CONFIG_NET
	{
		.procname	= "wmem_max",
		.data		= &sysctl_wmem_max,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= proc_dointvec_minmax,
		.extra1		= &one,
	},
	{
		.procname	= "rmem_max",
		.data		= &sysctl_rmem_max,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= proc_dointvec_minmax,
		.extra1		= &one,
	},
	{
		.procname	= "wmem_default",
		.data		= &sysctl_wmem_default,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= proc_dointvec_minmax,
		.extra1		= &one,
	},
	{
		.procname	= "rmem_default",
		.data		= &sysctl_rmem_default,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= proc_dointvec_minmax,
		.extra1		= &one,
	},
	{
		.procname	= "dev_weight",
		.data		= &weight_p,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= proc_dointvec
	},
	{
		.procname	= "netdev_max_backlog",
		.data		= &netdev_max_backlog,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= proc_dointvec
	},
#ifdef CONFIG_BPF_JIT
	{
		.procname	= "bpf_jit_enable",
		.data		= &bpf_jit_enable,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= proc_dointvec
	},
#endif
	{
		.procname	= "netdev_tstamp_prequeue",
		.data		= &netdev_tstamp_prequeue,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= proc_dointvec
	},
	{
		.procname	= "message_cost",
		.data		= &net_ratelimit_state.interval,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= proc_dointvec_jiffies,
	},
	{
		.procname	= "message_burst",
		.data		= &net_ratelimit_state.burst,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= proc_dointvec,
	},
	{
		.procname	= "optmem_max",
		.data		= &sysctl_optmem_max,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= proc_dointvec
	},
#ifdef CONFIG_RPS
	{
		.procname	= "rps_sock_flow_entries",
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= rps_sock_flow_sysctl
	},
#endif
#ifdef CONFIG_NET_FLOW_LIMIT
	{
		.procname	= "flow_limit_cpu_bitmap",
		.mode		= 0644,
		.proc_handler	= flow_limit_cpu_sysctl
	},
	{
		.procname	= "flow_limit_table_len",
		.data		= &netdev_flow_limit_table_len,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= flow_limit_table_len_sysctl
	},
#endif /* CONFIG_NET_FLOW_LIMIT */
#ifdef CONFIG_NET_LL_RX_POLL
	{
		.procname	= "low_latency_poll",
		.data		= &sysctl_net_ll_poll,
		.maxlen		= sizeof(unsigned long),
		.mode		= 0644,
		.proc_handler	= proc_doulongvec_minmax
	},
#endif
#endif /* CONFIG_NET */
	{
		.procname	= "netdev_budget",
		.data		= &netdev_budget,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= proc_dointvec
	},
	{
		.procname	= "warnings",
		.data		= &net_msg_warn,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= proc_dointvec
	},
	{ }
};

static struct ctl_table netns_core_table[] = {
	{
		.procname	= "somaxconn",
		.data		= &init_net.core.sysctl_somaxconn,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= proc_dointvec
	},
	{ }
};

static __net_init int sysctl_core_net_init(struct net *net)
{
	struct ctl_table *tbl;

	net->core.sysctl_somaxconn = SOMAXCONN;

	tbl = netns_core_table;
	if (!net_eq(net, &init_net)) {
		tbl = kmemdup(tbl, sizeof(netns_core_table), GFP_KERNEL);
		if (tbl == NULL)
			goto err_dup;

		tbl[0].data = &net->core.sysctl_somaxconn;

		/* Don't export any sysctls to unprivileged users */
		if (net->user_ns != &init_user_ns) {
			tbl[0].procname = NULL;
		}
	}

	net->core.sysctl_hdr = register_net_sysctl(net, "net/core", tbl);
	if (net->core.sysctl_hdr == NULL)
		goto err_reg;

	return 0;

err_reg:
	if (tbl != netns_core_table)
		kfree(tbl);
err_dup:
	return -ENOMEM;
}

static __net_exit void sysctl_core_net_exit(struct net *net)
{
	struct ctl_table *tbl;

	tbl = net->core.sysctl_hdr->ctl_table_arg;
	unregister_net_sysctl_table(net->core.sysctl_hdr);
	BUG_ON(tbl == netns_core_table);
	kfree(tbl);
}

static __net_initdata struct pernet_operations sysctl_core_ops = {
	.init = sysctl_core_net_init,
	.exit = sysctl_core_net_exit,
};

static __init int sysctl_core_init(void)
{
	register_net_sysctl(&init_net, "net/core", net_core_table);
	return register_pernet_subsys(&sysctl_core_ops);
}

fs_initcall(sysctl_core_init);
Commit	Line	Data
1da177e4 LT	1	/* -- linux-c --
	2	* sysctl_net_core.c: sysctl interface to net core subsystem.
	3	*
	4	* Begun April 1, 1996, Mike Shaver.
	5	* Added /proc/sys/net/core directory entry (empty =) ). [MS]
	6	*/
	7
	8	#include <linux/mm.h>
	9	#include <linux/sysctl.h>
1da177e4	10	#include <linux/module.h>
20380731	11	#include <linux/socket.h>
a37ae408	12	#include <linux/netdevice.h>
3fff4c42	13	#include <linux/ratelimit.h>
fec5e652	14	#include <linux/vmalloc.h>
33eb9cfc	15	#include <linux/init.h>
5a0e3ad6	16	#include <linux/slab.h>
7426a564	17	#include <linux/kmemleak.h>
3fff4c42	18
63d819ca	19	#include <net/ip.h>
20380731	20	#include <net/sock.h>
c5c177b4	21	#include <net/net_ratelimit.h>
06021292	22	#include <net/ll_poll.h>
1da177e4	23
cdda8891	24	static int one = 1;
cdda8891	25
fec5e652	26	#ifdef CONFIG_RPS
fe2c6338	27	static int rps_sock_flow_sysctl(struct ctl_table *table, int write,
fec5e652 TH	28	void __user buffer, size_t lenp, loff_t *ppos)
	29	{
	30	unsigned int orig_size, size;
	31	int ret, i;
fe2c6338	32	struct ctl_table tmp = {
fec5e652 TH	33	.data = &size,
	34	.maxlen = sizeof(size),
	35	.mode = table->mode
	36	};
	37	struct rps_sock_flow_table orig_sock_table, sock_table;
	38	static DEFINE_MUTEX(sock_flow_mutex);
	39
	40	mutex_lock(&sock_flow_mutex);
	41
6e3f7faf ED	42	orig_sock_table = rcu_dereference_protected(rps_sock_flow_table,
6e3f7faf ED	43	lockdep_is_held(&sock_flow_mutex));
fec5e652 TH	44	size = orig_size = orig_sock_table ? orig_sock_table->mask + 1 : 0;
	45
	46	ret = proc_dointvec(&tmp, write, buffer, lenp, ppos);
	47
	48	if (write) {
	49	if (size) {
	50	if (size > 1<<30) {
	51	/* Enforce limit to prevent overflow */
	52	mutex_unlock(&sock_flow_mutex);
	53	return -EINVAL;
	54	}
	55	size = roundup_pow_of_two(size);
	56	if (size != orig_size) {
	57	sock_table =
	58	vmalloc(RPS_SOCK_FLOW_TABLE_SIZE(size));
	59	if (!sock_table) {
	60	mutex_unlock(&sock_flow_mutex);
	61	return -ENOMEM;
	62	}
	63
	64	sock_table->mask = size - 1;
	65	} else
	66	sock_table = orig_sock_table;
	67
	68	for (i = 0; i < size; i++)
	69	sock_table->ents[i] = RPS_NO_CPU;
	70	} else
	71	sock_table = NULL;
	72
	73	if (sock_table != orig_sock_table) {
	74	rcu_assign_pointer(rps_sock_flow_table, sock_table);
adc9300e	75	if (sock_table)
c5905afb	76	static_key_slow_inc(&rps_needed);
adc9300e	77	if (orig_sock_table) {
c5905afb	78	static_key_slow_dec(&rps_needed);
adc9300e ED	79	synchronize_rcu();
	80	vfree(orig_sock_table);
	81	}
fec5e652 TH	82	}
	83	}
	84
	85	mutex_unlock(&sock_flow_mutex);
	86
	87	return ret;
	88	}
	89	#endif /* CONFIG_RPS */
	90
99bbc707 WB	91	#ifdef CONFIG_NET_FLOW_LIMIT
	92	static DEFINE_MUTEX(flow_limit_update_mutex);
	93
fe2c6338	94	static int flow_limit_cpu_sysctl(struct ctl_table *table, int write,
99bbc707 WB	95	void __user buffer, size_t lenp,
	96	loff_t *ppos)
	97	{
	98	struct sd_flow_limit *cur;
	99	struct softnet_data *sd;
	100	cpumask_var_t mask;
	101	int i, len, ret = 0;
	102
	103	if (!alloc_cpumask_var(&mask, GFP_KERNEL))
	104	return -ENOMEM;
	105
	106	if (write) {
	107	ret = cpumask_parse_user(buffer, *lenp, mask);
	108	if (ret)
	109	goto done;
	110
	111	mutex_lock(&flow_limit_update_mutex);
	112	len = sizeof(*cur) + netdev_flow_limit_table_len;
	113	for_each_possible_cpu(i) {
	114	sd = &per_cpu(softnet_data, i);
	115	cur = rcu_dereference_protected(sd->flow_limit,
	116	lockdep_is_held(&flow_limit_update_mutex));
	117	if (cur && !cpumask_test_cpu(i, mask)) {
	118	RCU_INIT_POINTER(sd->flow_limit, NULL);
	119	synchronize_rcu();
	120	kfree(cur);
	121	} else if (!cur && cpumask_test_cpu(i, mask)) {
	122	cur = kzalloc(len, GFP_KERNEL);
	123	if (!cur) {
	124	/* not unwinding previous changes */
	125	ret = -ENOMEM;
	126	goto write_unlock;
	127	}
	128	cur->num_buckets = netdev_flow_limit_table_len;
	129	rcu_assign_pointer(sd->flow_limit, cur);
	130	}
	131	}
	132	write_unlock:
	133	mutex_unlock(&flow_limit_update_mutex);
	134	} else {
	135	if (ppos \|\| !lenp) {
	136	*lenp = 0;
	137	goto done;
	138	}
	139
	140	cpumask_clear(mask);
	141	rcu_read_lock();
	142	for_each_possible_cpu(i) {
	143	sd = &per_cpu(softnet_data, i);
	144	if (rcu_dereference(sd->flow_limit))
	145	cpumask_set_cpu(i, mask);
	146	}
	147	rcu_read_unlock();
	148
	149	len = cpumask_scnprintf(buffer, *lenp, mask);
	150	*lenp = len + 1;
	151	*ppos += len + 1;
	152	}
	153
	154	done:
	155	free_cpumask_var(mask);
	156	return ret;
	157	}
	158
fe2c6338	159	static int flow_limit_table_len_sysctl(struct ctl_table *table, int write,
99bbc707 WB	160	void __user buffer, size_t lenp,
	161	loff_t *ppos)
	162	{
	163	unsigned int old, *ptr;
	164	int ret;
	165
	166	mutex_lock(&flow_limit_update_mutex);
	167
	168	ptr = table->data;
	169	old = *ptr;
	170	ret = proc_dointvec(table, write, buffer, lenp, ppos);
	171	if (!ret && write && !is_power_of_2(*ptr)) {
	172	*ptr = old;
	173	ret = -EINVAL;
	174	}
	175
	176	mutex_unlock(&flow_limit_update_mutex);
	177	return ret;
	178	}
	179	#endif /* CONFIG_NET_FLOW_LIMIT */
	180
33eb9cfc	181	static struct ctl_table net_core_table[] = {
1da177e4 LT	182	#ifdef CONFIG_NET
1da177e4 LT	183	{
1da177e4 LT	184	.procname = "wmem_max",
	185	.data = &sysctl_wmem_max,
	186	.maxlen = sizeof(int),
	187	.mode = 0644,
cdda8891	188	.proc_handler = proc_dointvec_minmax,
cdda8891	189	.extra1 = &one,
1da177e4 LT	190	},
1da177e4 LT	191	{
1da177e4 LT	192	.procname = "rmem_max",
	193	.data = &sysctl_rmem_max,
	194	.maxlen = sizeof(int),
	195	.mode = 0644,
cdda8891	196	.proc_handler = proc_dointvec_minmax,
cdda8891	197	.extra1 = &one,
1da177e4 LT	198	},
1da177e4 LT	199	{
1da177e4 LT	200	.procname = "wmem_default",
	201	.data = &sysctl_wmem_default,
	202	.maxlen = sizeof(int),
	203	.mode = 0644,
cdda8891	204	.proc_handler = proc_dointvec_minmax,
cdda8891	205	.extra1 = &one,
1da177e4 LT	206	},
1da177e4 LT	207	{
1da177e4 LT	208	.procname = "rmem_default",
	209	.data = &sysctl_rmem_default,
	210	.maxlen = sizeof(int),
	211	.mode = 0644,
cdda8891	212	.proc_handler = proc_dointvec_minmax,
cdda8891	213	.extra1 = &one,
1da177e4 LT	214	},
1da177e4 LT	215	{
1da177e4 LT	216	.procname = "dev_weight",
	217	.data = &weight_p,
	218	.maxlen = sizeof(int),
	219	.mode = 0644,
6d9f239a	220	.proc_handler = proc_dointvec
1da177e4 LT	221	},
1da177e4 LT	222	{
1da177e4 LT	223	.procname = "netdev_max_backlog",
	224	.data = &netdev_max_backlog,
	225	.maxlen = sizeof(int),
	226	.mode = 0644,
6d9f239a	227	.proc_handler = proc_dointvec
1da177e4	228	},
0a14842f ED	229	#ifdef CONFIG_BPF_JIT
	230	{
	231	.procname = "bpf_jit_enable",
	232	.data = &bpf_jit_enable,
	233	.maxlen = sizeof(int),
	234	.mode = 0644,
	235	.proc_handler = proc_dointvec
	236	},
	237	#endif
3b098e2d ED	238	{
	239	.procname = "netdev_tstamp_prequeue",
	240	.data = &netdev_tstamp_prequeue,
	241	.maxlen = sizeof(int),
	242	.mode = 0644,
	243	.proc_handler = proc_dointvec
	244	},
1da177e4	245	{
1da177e4	246	.procname = "message_cost",
717115e1	247	.data = &net_ratelimit_state.interval,
1da177e4 LT	248	.maxlen = sizeof(int),
1da177e4 LT	249	.mode = 0644,
6d9f239a	250	.proc_handler = proc_dointvec_jiffies,
1da177e4 LT	251	},
1da177e4 LT	252	{
1da177e4	253	.procname = "message_burst",
717115e1	254	.data = &net_ratelimit_state.burst,
1da177e4 LT	255	.maxlen = sizeof(int),
1da177e4 LT	256	.mode = 0644,
6d9f239a	257	.proc_handler = proc_dointvec,
1da177e4 LT	258	},
1da177e4 LT	259	{
1da177e4 LT	260	.procname = "optmem_max",
	261	.data = &sysctl_optmem_max,
	262	.maxlen = sizeof(int),
	263	.mode = 0644,
6d9f239a	264	.proc_handler = proc_dointvec
1da177e4	265	},
fec5e652 TH	266	#ifdef CONFIG_RPS
	267	{
	268	.procname = "rps_sock_flow_entries",
	269	.maxlen = sizeof(int),
	270	.mode = 0644,
	271	.proc_handler = rps_sock_flow_sysctl
	272	},
	273	#endif
99bbc707 WB	274	#ifdef CONFIG_NET_FLOW_LIMIT
	275	{
	276	.procname = "flow_limit_cpu_bitmap",
	277	.mode = 0644,
	278	.proc_handler = flow_limit_cpu_sysctl
	279	},
	280	{
	281	.procname = "flow_limit_table_len",
	282	.data = &netdev_flow_limit_table_len,
	283	.maxlen = sizeof(int),
	284	.mode = 0644,
	285	.proc_handler = flow_limit_table_len_sysctl
	286	},
	287	#endif /* CONFIG_NET_FLOW_LIMIT */
06021292 ET	288	#ifdef CONFIG_NET_LL_RX_POLL
	289	{
	290	.procname = "low_latency_poll",
	291	.data = &sysctl_net_ll_poll,
	292	.maxlen = sizeof(unsigned long),
	293	.mode = 0644,
	294	.proc_handler = proc_doulongvec_minmax
	295	},
	296	#endif
1da177e4	297	#endif /* CONFIG_NET */
51b0bded	298	{
51b0bded SH	299	.procname = "netdev_budget",
	300	.data = &netdev_budget,
	301	.maxlen = sizeof(int),
	302	.mode = 0644,
6d9f239a	303	.proc_handler = proc_dointvec
51b0bded	304	},
a2a316fd	305	{
a2a316fd SH	306	.procname = "warnings",
	307	.data = &net_msg_warn,
	308	.maxlen = sizeof(int),
	309	.mode = 0644,
6d9f239a	310	.proc_handler = proc_dointvec
a2a316fd	311	},
f8572d8f	312	{ }
1da177e4	313	};
33eb9cfc	314
d5a4502e PE	315	static struct ctl_table netns_core_table[] = {
d5a4502e PE	316	{
d5a4502e PE	317	.procname = "somaxconn",
	318	.data = &init_net.core.sysctl_somaxconn,
	319	.maxlen = sizeof(int),
	320	.mode = 0644,
6d9f239a	321	.proc_handler = proc_dointvec
d5a4502e	322	},
f8572d8f	323	{ }
d5a4502e PE	324	};
d5a4502e PE	325
024626e3	326	static __net_init int sysctl_core_net_init(struct net *net)
33eb9cfc	327	{
d5a4502e	328	struct ctl_table *tbl;
024626e3	329
8efa6e93	330	net->core.sysctl_somaxconn = SOMAXCONN;
b8e1f9b5	331
d5a4502e	332	tbl = netns_core_table;
09ad9bc7	333	if (!net_eq(net, &init_net)) {
d5a4502e	334	tbl = kmemdup(tbl, sizeof(netns_core_table), GFP_KERNEL);
024626e3 PE	335	if (tbl == NULL)
	336	goto err_dup;
	337
d5a4502e	338	tbl[0].data = &net->core.sysctl_somaxconn;
464dc801 EB	339
	340	/* Don't export any sysctls to unprivileged users */
	341	if (net->user_ns != &init_user_ns) {
	342	tbl[0].procname = NULL;
	343	}
024626e3 PE	344	}
024626e3 PE	345
ec8f23ce	346	net->core.sysctl_hdr = register_net_sysctl(net, "net/core", tbl);
8efa6e93	347	if (net->core.sysctl_hdr == NULL)
024626e3	348	goto err_reg;
33eb9cfc	349
024626e3 PE	350	return 0;
	351
	352	err_reg:
d5a4502e	353	if (tbl != netns_core_table)
024626e3 PE	354	kfree(tbl);
	355	err_dup:
	356	return -ENOMEM;
	357	}
	358
	359	static __net_exit void sysctl_core_net_exit(struct net *net)
	360	{
	361	struct ctl_table *tbl;
	362
8efa6e93 PE	363	tbl = net->core.sysctl_hdr->ctl_table_arg;
8efa6e93 PE	364	unregister_net_sysctl_table(net->core.sysctl_hdr);
d5a4502e	365	BUG_ON(tbl == netns_core_table);
024626e3 PE	366	kfree(tbl);
	367	}
	368
	369	static __net_initdata struct pernet_operations sysctl_core_ops = {
	370	.init = sysctl_core_net_init,
	371	.exit = sysctl_core_net_exit,
	372	};
	373
	374	static __init int sysctl_core_init(void)
	375	{
43444757	376	register_net_sysctl(&init_net, "net/core", net_core_table);
024626e3	377	return register_pernet_subsys(&sysctl_core_ops);
33eb9cfc PE	378	}
33eb9cfc PE	379
b27aeadb	380	fs_initcall(sysctl_core_init);