xref: /linux/net/ipv4/sysctl_net_ipv4.c (revision 13091aa30535b719e269f20a7bc34002bf5afae5)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * sysctl_net_ipv4.c: sysctl interface to net IPV4 subsystem.
4  *
5  * Begun April 1, 1996, Mike Shaver.
6  * Added /proc/sys/net/ipv4 directory entry (empty =) ). [MS]
7  */
8 
9 #include <linux/mm.h>
10 #include <linux/module.h>
11 #include <linux/sysctl.h>
12 #include <linux/igmp.h>
13 #include <linux/inetdevice.h>
14 #include <linux/seqlock.h>
15 #include <linux/init.h>
16 #include <linux/slab.h>
17 #include <linux/nsproxy.h>
18 #include <linux/swap.h>
19 #include <net/snmp.h>
20 #include <net/icmp.h>
21 #include <net/ip.h>
22 #include <net/route.h>
23 #include <net/tcp.h>
24 #include <net/udp.h>
25 #include <net/cipso_ipv4.h>
26 #include <net/inet_frag.h>
27 #include <net/ping.h>
28 #include <net/protocol.h>
29 #include <net/netevent.h>
30 
31 static int zero;
32 static int one = 1;
33 static int two = 2;
34 static int four = 4;
35 static int thousand = 1000;
36 static int gso_max_segs = GSO_MAX_SEGS;
37 static int tcp_retr1_max = 255;
38 static int ip_local_port_range_min[] = { 1, 1 };
39 static int ip_local_port_range_max[] = { 65535, 65535 };
40 static int tcp_adv_win_scale_min = -31;
41 static int tcp_adv_win_scale_max = 31;
42 static int tcp_min_snd_mss_min = TCP_MIN_SND_MSS;
43 static int tcp_min_snd_mss_max = 65535;
44 static int ip_privileged_port_min;
45 static int ip_privileged_port_max = 65535;
46 static int ip_ttl_min = 1;
47 static int ip_ttl_max = 255;
48 static int tcp_syn_retries_min = 1;
49 static int tcp_syn_retries_max = MAX_TCP_SYNCNT;
50 static int ip_ping_group_range_min[] = { 0, 0 };
51 static int ip_ping_group_range_max[] = { GID_T_MAX, GID_T_MAX };
52 static int comp_sack_nr_max = 255;
53 static u32 u32_max_div_HZ = UINT_MAX / HZ;
54 static int one_day_secs = 24 * 3600;
55 
56 /* obsolete */
57 static int sysctl_tcp_low_latency __read_mostly;
58 
59 /* Update system visible IP port range */
60 static void set_local_port_range(struct net *net, int range[2])
61 {
62 	bool same_parity = !((range[0] ^ range[1]) & 1);
63 
64 	write_seqlock_bh(&net->ipv4.ip_local_ports.lock);
65 	if (same_parity && !net->ipv4.ip_local_ports.warned) {
66 		net->ipv4.ip_local_ports.warned = true;
67 		pr_err_ratelimited("ip_local_port_range: prefer different parity for start/end values.\n");
68 	}
69 	net->ipv4.ip_local_ports.range[0] = range[0];
70 	net->ipv4.ip_local_ports.range[1] = range[1];
71 	write_sequnlock_bh(&net->ipv4.ip_local_ports.lock);
72 }
73 
74 /* Validate changes from /proc interface. */
75 static int ipv4_local_port_range(struct ctl_table *table, int write,
76 				 void __user *buffer,
77 				 size_t *lenp, loff_t *ppos)
78 {
79 	struct net *net =
80 		container_of(table->data, struct net, ipv4.ip_local_ports.range);
81 	int ret;
82 	int range[2];
83 	struct ctl_table tmp = {
84 		.data = &range,
85 		.maxlen = sizeof(range),
86 		.mode = table->mode,
87 		.extra1 = &ip_local_port_range_min,
88 		.extra2 = &ip_local_port_range_max,
89 	};
90 
91 	inet_get_local_port_range(net, &range[0], &range[1]);
92 
93 	ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
94 
95 	if (write && ret == 0) {
96 		/* Ensure that the upper limit is not smaller than the lower,
97 		 * and that the lower does not encroach upon the privileged
98 		 * port limit.
99 		 */
100 		if ((range[1] < range[0]) ||
101 		    (range[0] < net->ipv4.sysctl_ip_prot_sock))
102 			ret = -EINVAL;
103 		else
104 			set_local_port_range(net, range);
105 	}
106 
107 	return ret;
108 }
109 
110 /* Validate changes from /proc interface. */
111 static int ipv4_privileged_ports(struct ctl_table *table, int write,
112 				void __user *buffer, size_t *lenp, loff_t *ppos)
113 {
114 	struct net *net = container_of(table->data, struct net,
115 	    ipv4.sysctl_ip_prot_sock);
116 	int ret;
117 	int pports;
118 	int range[2];
119 	struct ctl_table tmp = {
120 		.data = &pports,
121 		.maxlen = sizeof(pports),
122 		.mode = table->mode,
123 		.extra1 = &ip_privileged_port_min,
124 		.extra2 = &ip_privileged_port_max,
125 	};
126 
127 	pports = net->ipv4.sysctl_ip_prot_sock;
128 
129 	ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
130 
131 	if (write && ret == 0) {
132 		inet_get_local_port_range(net, &range[0], &range[1]);
133 		/* Ensure that the local port range doesn't overlap with the
134 		 * privileged port range.
135 		 */
136 		if (range[0] < pports)
137 			ret = -EINVAL;
138 		else
139 			net->ipv4.sysctl_ip_prot_sock = pports;
140 	}
141 
142 	return ret;
143 }
144 
145 static void inet_get_ping_group_range_table(struct ctl_table *table, kgid_t *low, kgid_t *high)
146 {
147 	kgid_t *data = table->data;
148 	struct net *net =
149 		container_of(table->data, struct net, ipv4.ping_group_range.range);
150 	unsigned int seq;
151 	do {
152 		seq = read_seqbegin(&net->ipv4.ping_group_range.lock);
153 
154 		*low = data[0];
155 		*high = data[1];
156 	} while (read_seqretry(&net->ipv4.ping_group_range.lock, seq));
157 }
158 
159 /* Update system visible IP port range */
160 static void set_ping_group_range(struct ctl_table *table, kgid_t low, kgid_t high)
161 {
162 	kgid_t *data = table->data;
163 	struct net *net =
164 		container_of(table->data, struct net, ipv4.ping_group_range.range);
165 	write_seqlock(&net->ipv4.ping_group_range.lock);
166 	data[0] = low;
167 	data[1] = high;
168 	write_sequnlock(&net->ipv4.ping_group_range.lock);
169 }
170 
171 /* Validate changes from /proc interface. */
172 static int ipv4_ping_group_range(struct ctl_table *table, int write,
173 				 void __user *buffer,
174 				 size_t *lenp, loff_t *ppos)
175 {
176 	struct user_namespace *user_ns = current_user_ns();
177 	int ret;
178 	gid_t urange[2];
179 	kgid_t low, high;
180 	struct ctl_table tmp = {
181 		.data = &urange,
182 		.maxlen = sizeof(urange),
183 		.mode = table->mode,
184 		.extra1 = &ip_ping_group_range_min,
185 		.extra2 = &ip_ping_group_range_max,
186 	};
187 
188 	inet_get_ping_group_range_table(table, &low, &high);
189 	urange[0] = from_kgid_munged(user_ns, low);
190 	urange[1] = from_kgid_munged(user_ns, high);
191 	ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
192 
193 	if (write && ret == 0) {
194 		low = make_kgid(user_ns, urange[0]);
195 		high = make_kgid(user_ns, urange[1]);
196 		if (!gid_valid(low) || !gid_valid(high))
197 			return -EINVAL;
198 		if (urange[1] < urange[0] || gid_lt(high, low)) {
199 			low = make_kgid(&init_user_ns, 1);
200 			high = make_kgid(&init_user_ns, 0);
201 		}
202 		set_ping_group_range(table, low, high);
203 	}
204 
205 	return ret;
206 }
207 
208 static int ipv4_fwd_update_priority(struct ctl_table *table, int write,
209 				    void __user *buffer,
210 				    size_t *lenp, loff_t *ppos)
211 {
212 	struct net *net;
213 	int ret;
214 
215 	net = container_of(table->data, struct net,
216 			   ipv4.sysctl_ip_fwd_update_priority);
217 	ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
218 	if (write && ret == 0)
219 		call_netevent_notifiers(NETEVENT_IPV4_FWD_UPDATE_PRIORITY_UPDATE,
220 					net);
221 
222 	return ret;
223 }
224 
225 static int proc_tcp_congestion_control(struct ctl_table *ctl, int write,
226 				       void __user *buffer, size_t *lenp, loff_t *ppos)
227 {
228 	struct net *net = container_of(ctl->data, struct net,
229 				       ipv4.tcp_congestion_control);
230 	char val[TCP_CA_NAME_MAX];
231 	struct ctl_table tbl = {
232 		.data = val,
233 		.maxlen = TCP_CA_NAME_MAX,
234 	};
235 	int ret;
236 
237 	tcp_get_default_congestion_control(net, val);
238 
239 	ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
240 	if (write && ret == 0)
241 		ret = tcp_set_default_congestion_control(net, val);
242 	return ret;
243 }
244 
245 static int proc_tcp_available_congestion_control(struct ctl_table *ctl,
246 						 int write,
247 						 void __user *buffer, size_t *lenp,
248 						 loff_t *ppos)
249 {
250 	struct ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX, };
251 	int ret;
252 
253 	tbl.data = kmalloc(tbl.maxlen, GFP_USER);
254 	if (!tbl.data)
255 		return -ENOMEM;
256 	tcp_get_available_congestion_control(tbl.data, TCP_CA_BUF_MAX);
257 	ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
258 	kfree(tbl.data);
259 	return ret;
260 }
261 
262 static int proc_allowed_congestion_control(struct ctl_table *ctl,
263 					   int write,
264 					   void __user *buffer, size_t *lenp,
265 					   loff_t *ppos)
266 {
267 	struct ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX };
268 	int ret;
269 
270 	tbl.data = kmalloc(tbl.maxlen, GFP_USER);
271 	if (!tbl.data)
272 		return -ENOMEM;
273 
274 	tcp_get_allowed_congestion_control(tbl.data, tbl.maxlen);
275 	ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
276 	if (write && ret == 0)
277 		ret = tcp_set_allowed_congestion_control(tbl.data);
278 	kfree(tbl.data);
279 	return ret;
280 }
281 
282 static int sscanf_key(char *buf, __le32 *key)
283 {
284 	u32 user_key[4];
285 	int i, ret = 0;
286 
287 	if (sscanf(buf, "%x-%x-%x-%x", user_key, user_key + 1,
288 		   user_key + 2, user_key + 3) != 4) {
289 		ret = -EINVAL;
290 	} else {
291 		for (i = 0; i < ARRAY_SIZE(user_key); i++)
292 			key[i] = cpu_to_le32(user_key[i]);
293 	}
294 	pr_debug("proc TFO key set 0x%x-%x-%x-%x <- 0x%s: %u\n",
295 		 user_key[0], user_key[1], user_key[2], user_key[3], buf, ret);
296 
297 	return ret;
298 }
299 
300 static int proc_tcp_fastopen_key(struct ctl_table *table, int write,
301 				 void __user *buffer, size_t *lenp,
302 				 loff_t *ppos)
303 {
304 	struct net *net = container_of(table->data, struct net,
305 	    ipv4.sysctl_tcp_fastopen);
306 	/* maxlen to print the list of keys in hex (*2), with dashes
307 	 * separating doublewords and a comma in between keys.
308 	 */
309 	struct ctl_table tbl = { .maxlen = ((TCP_FASTOPEN_KEY_LENGTH *
310 					    2 * TCP_FASTOPEN_KEY_MAX) +
311 					    (TCP_FASTOPEN_KEY_MAX * 5)) };
312 	struct tcp_fastopen_context *ctx;
313 	u32 user_key[TCP_FASTOPEN_KEY_MAX * 4];
314 	__le32 key[TCP_FASTOPEN_KEY_MAX * 4];
315 	char *backup_data;
316 	int ret, i = 0, off = 0, n_keys = 0;
317 
318 	tbl.data = kmalloc(tbl.maxlen, GFP_KERNEL);
319 	if (!tbl.data)
320 		return -ENOMEM;
321 
322 	rcu_read_lock();
323 	ctx = rcu_dereference(net->ipv4.tcp_fastopen_ctx);
324 	if (ctx) {
325 		n_keys = tcp_fastopen_context_len(ctx);
326 		memcpy(&key[0], &ctx->key[0], TCP_FASTOPEN_KEY_LENGTH * n_keys);
327 	}
328 	rcu_read_unlock();
329 
330 	if (!n_keys) {
331 		memset(&key[0], 0, TCP_FASTOPEN_KEY_LENGTH);
332 		n_keys = 1;
333 	}
334 
335 	for (i = 0; i < n_keys * 4; i++)
336 		user_key[i] = le32_to_cpu(key[i]);
337 
338 	for (i = 0; i < n_keys; i++) {
339 		off += snprintf(tbl.data + off, tbl.maxlen - off,
340 				"%08x-%08x-%08x-%08x",
341 				user_key[i * 4],
342 				user_key[i * 4 + 1],
343 				user_key[i * 4 + 2],
344 				user_key[i * 4 + 3]);
345 		if (i + 1 < n_keys)
346 			off += snprintf(tbl.data + off, tbl.maxlen - off, ",");
347 	}
348 
349 	ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
350 
351 	if (write && ret == 0) {
352 		backup_data = strchr(tbl.data, ',');
353 		if (backup_data) {
354 			*backup_data = '\0';
355 			backup_data++;
356 		}
357 		if (sscanf_key(tbl.data, key)) {
358 			ret = -EINVAL;
359 			goto bad_key;
360 		}
361 		if (backup_data) {
362 			if (sscanf_key(backup_data, key + 4)) {
363 				ret = -EINVAL;
364 				goto bad_key;
365 			}
366 		}
367 		tcp_fastopen_reset_cipher(net, NULL, key,
368 					  backup_data ? key + 4 : NULL,
369 					  TCP_FASTOPEN_KEY_LENGTH);
370 	}
371 
372 bad_key:
373 	kfree(tbl.data);
374 	return ret;
375 }
376 
377 static void proc_configure_early_demux(int enabled, int protocol)
378 {
379 	struct net_protocol *ipprot;
380 #if IS_ENABLED(CONFIG_IPV6)
381 	struct inet6_protocol *ip6prot;
382 #endif
383 
384 	rcu_read_lock();
385 
386 	ipprot = rcu_dereference(inet_protos[protocol]);
387 	if (ipprot)
388 		ipprot->early_demux = enabled ? ipprot->early_demux_handler :
389 						NULL;
390 
391 #if IS_ENABLED(CONFIG_IPV6)
392 	ip6prot = rcu_dereference(inet6_protos[protocol]);
393 	if (ip6prot)
394 		ip6prot->early_demux = enabled ? ip6prot->early_demux_handler :
395 						 NULL;
396 #endif
397 	rcu_read_unlock();
398 }
399 
400 static int proc_tcp_early_demux(struct ctl_table *table, int write,
401 				void __user *buffer, size_t *lenp, loff_t *ppos)
402 {
403 	int ret = 0;
404 
405 	ret = proc_dointvec(table, write, buffer, lenp, ppos);
406 
407 	if (write && !ret) {
408 		int enabled = init_net.ipv4.sysctl_tcp_early_demux;
409 
410 		proc_configure_early_demux(enabled, IPPROTO_TCP);
411 	}
412 
413 	return ret;
414 }
415 
416 static int proc_udp_early_demux(struct ctl_table *table, int write,
417 				void __user *buffer, size_t *lenp, loff_t *ppos)
418 {
419 	int ret = 0;
420 
421 	ret = proc_dointvec(table, write, buffer, lenp, ppos);
422 
423 	if (write && !ret) {
424 		int enabled = init_net.ipv4.sysctl_udp_early_demux;
425 
426 		proc_configure_early_demux(enabled, IPPROTO_UDP);
427 	}
428 
429 	return ret;
430 }
431 
432 static int proc_tfo_blackhole_detect_timeout(struct ctl_table *table,
433 					     int write,
434 					     void __user *buffer,
435 					     size_t *lenp, loff_t *ppos)
436 {
437 	struct net *net = container_of(table->data, struct net,
438 	    ipv4.sysctl_tcp_fastopen_blackhole_timeout);
439 	int ret;
440 
441 	ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
442 	if (write && ret == 0)
443 		atomic_set(&net->ipv4.tfo_active_disable_times, 0);
444 
445 	return ret;
446 }
447 
448 static int proc_tcp_available_ulp(struct ctl_table *ctl,
449 				  int write,
450 				  void __user *buffer, size_t *lenp,
451 				  loff_t *ppos)
452 {
453 	struct ctl_table tbl = { .maxlen = TCP_ULP_BUF_MAX, };
454 	int ret;
455 
456 	tbl.data = kmalloc(tbl.maxlen, GFP_USER);
457 	if (!tbl.data)
458 		return -ENOMEM;
459 	tcp_get_available_ulp(tbl.data, TCP_ULP_BUF_MAX);
460 	ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
461 	kfree(tbl.data);
462 
463 	return ret;
464 }
465 
466 #ifdef CONFIG_IP_ROUTE_MULTIPATH
467 static int proc_fib_multipath_hash_policy(struct ctl_table *table, int write,
468 					  void __user *buffer, size_t *lenp,
469 					  loff_t *ppos)
470 {
471 	struct net *net = container_of(table->data, struct net,
472 	    ipv4.sysctl_fib_multipath_hash_policy);
473 	int ret;
474 
475 	ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
476 	if (write && ret == 0)
477 		call_netevent_notifiers(NETEVENT_IPV4_MPATH_HASH_UPDATE, net);
478 
479 	return ret;
480 }
481 #endif
482 
483 static struct ctl_table ipv4_table[] = {
484 	{
485 		.procname	= "tcp_max_orphans",
486 		.data		= &sysctl_tcp_max_orphans,
487 		.maxlen		= sizeof(int),
488 		.mode		= 0644,
489 		.proc_handler	= proc_dointvec
490 	},
491 	{
492 		.procname	= "inet_peer_threshold",
493 		.data		= &inet_peer_threshold,
494 		.maxlen		= sizeof(int),
495 		.mode		= 0644,
496 		.proc_handler	= proc_dointvec
497 	},
498 	{
499 		.procname	= "inet_peer_minttl",
500 		.data		= &inet_peer_minttl,
501 		.maxlen		= sizeof(int),
502 		.mode		= 0644,
503 		.proc_handler	= proc_dointvec_jiffies,
504 	},
505 	{
506 		.procname	= "inet_peer_maxttl",
507 		.data		= &inet_peer_maxttl,
508 		.maxlen		= sizeof(int),
509 		.mode		= 0644,
510 		.proc_handler	= proc_dointvec_jiffies,
511 	},
512 	{
513 		.procname	= "tcp_mem",
514 		.maxlen		= sizeof(sysctl_tcp_mem),
515 		.data		= &sysctl_tcp_mem,
516 		.mode		= 0644,
517 		.proc_handler	= proc_doulongvec_minmax,
518 	},
519 	{
520 		.procname	= "tcp_low_latency",
521 		.data		= &sysctl_tcp_low_latency,
522 		.maxlen		= sizeof(int),
523 		.mode		= 0644,
524 		.proc_handler	= proc_dointvec
525 	},
526 #ifdef CONFIG_NETLABEL
527 	{
528 		.procname	= "cipso_cache_enable",
529 		.data		= &cipso_v4_cache_enabled,
530 		.maxlen		= sizeof(int),
531 		.mode		= 0644,
532 		.proc_handler	= proc_dointvec,
533 	},
534 	{
535 		.procname	= "cipso_cache_bucket_size",
536 		.data		= &cipso_v4_cache_bucketsize,
537 		.maxlen		= sizeof(int),
538 		.mode		= 0644,
539 		.proc_handler	= proc_dointvec,
540 	},
541 	{
542 		.procname	= "cipso_rbm_optfmt",
543 		.data		= &cipso_v4_rbm_optfmt,
544 		.maxlen		= sizeof(int),
545 		.mode		= 0644,
546 		.proc_handler	= proc_dointvec,
547 	},
548 	{
549 		.procname	= "cipso_rbm_strictvalid",
550 		.data		= &cipso_v4_rbm_strictvalid,
551 		.maxlen		= sizeof(int),
552 		.mode		= 0644,
553 		.proc_handler	= proc_dointvec,
554 	},
555 #endif /* CONFIG_NETLABEL */
556 	{
557 		.procname	= "tcp_available_congestion_control",
558 		.maxlen		= TCP_CA_BUF_MAX,
559 		.mode		= 0444,
560 		.proc_handler   = proc_tcp_available_congestion_control,
561 	},
562 	{
563 		.procname	= "tcp_allowed_congestion_control",
564 		.maxlen		= TCP_CA_BUF_MAX,
565 		.mode		= 0644,
566 		.proc_handler   = proc_allowed_congestion_control,
567 	},
568 	{
569 		.procname	= "tcp_available_ulp",
570 		.maxlen		= TCP_ULP_BUF_MAX,
571 		.mode		= 0444,
572 		.proc_handler   = proc_tcp_available_ulp,
573 	},
574 	{
575 		.procname	= "icmp_msgs_per_sec",
576 		.data		= &sysctl_icmp_msgs_per_sec,
577 		.maxlen		= sizeof(int),
578 		.mode		= 0644,
579 		.proc_handler	= proc_dointvec_minmax,
580 		.extra1		= &zero,
581 	},
582 	{
583 		.procname	= "icmp_msgs_burst",
584 		.data		= &sysctl_icmp_msgs_burst,
585 		.maxlen		= sizeof(int),
586 		.mode		= 0644,
587 		.proc_handler	= proc_dointvec_minmax,
588 		.extra1		= &zero,
589 	},
590 	{
591 		.procname	= "udp_mem",
592 		.data		= &sysctl_udp_mem,
593 		.maxlen		= sizeof(sysctl_udp_mem),
594 		.mode		= 0644,
595 		.proc_handler	= proc_doulongvec_minmax,
596 	},
597 	{
598 		.procname	= "fib_sync_mem",
599 		.data		= &sysctl_fib_sync_mem,
600 		.maxlen		= sizeof(sysctl_fib_sync_mem),
601 		.mode		= 0644,
602 		.proc_handler	= proc_douintvec_minmax,
603 		.extra1		= &sysctl_fib_sync_mem_min,
604 		.extra2		= &sysctl_fib_sync_mem_max,
605 	},
606 	{
607 		.procname	= "tcp_rx_skb_cache",
608 		.data		= &tcp_rx_skb_cache_key.key,
609 		.mode		= 0644,
610 		.proc_handler	= proc_do_static_key,
611 	},
612 	{
613 		.procname	= "tcp_tx_skb_cache",
614 		.data		= &tcp_tx_skb_cache_key.key,
615 		.mode		= 0644,
616 		.proc_handler	= proc_do_static_key,
617 	},
618 	{ }
619 };
620 
621 static struct ctl_table ipv4_net_table[] = {
622 	{
623 		.procname	= "icmp_echo_ignore_all",
624 		.data		= &init_net.ipv4.sysctl_icmp_echo_ignore_all,
625 		.maxlen		= sizeof(int),
626 		.mode		= 0644,
627 		.proc_handler	= proc_dointvec
628 	},
629 	{
630 		.procname	= "icmp_echo_ignore_broadcasts",
631 		.data		= &init_net.ipv4.sysctl_icmp_echo_ignore_broadcasts,
632 		.maxlen		= sizeof(int),
633 		.mode		= 0644,
634 		.proc_handler	= proc_dointvec
635 	},
636 	{
637 		.procname	= "icmp_ignore_bogus_error_responses",
638 		.data		= &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses,
639 		.maxlen		= sizeof(int),
640 		.mode		= 0644,
641 		.proc_handler	= proc_dointvec
642 	},
643 	{
644 		.procname	= "icmp_errors_use_inbound_ifaddr",
645 		.data		= &init_net.ipv4.sysctl_icmp_errors_use_inbound_ifaddr,
646 		.maxlen		= sizeof(int),
647 		.mode		= 0644,
648 		.proc_handler	= proc_dointvec
649 	},
650 	{
651 		.procname	= "icmp_ratelimit",
652 		.data		= &init_net.ipv4.sysctl_icmp_ratelimit,
653 		.maxlen		= sizeof(int),
654 		.mode		= 0644,
655 		.proc_handler	= proc_dointvec_ms_jiffies,
656 	},
657 	{
658 		.procname	= "icmp_ratemask",
659 		.data		= &init_net.ipv4.sysctl_icmp_ratemask,
660 		.maxlen		= sizeof(int),
661 		.mode		= 0644,
662 		.proc_handler	= proc_dointvec
663 	},
664 	{
665 		.procname	= "ping_group_range",
666 		.data		= &init_net.ipv4.ping_group_range.range,
667 		.maxlen		= sizeof(gid_t)*2,
668 		.mode		= 0644,
669 		.proc_handler	= ipv4_ping_group_range,
670 	},
671 #ifdef CONFIG_NET_L3_MASTER_DEV
672 	{
673 		.procname	= "raw_l3mdev_accept",
674 		.data		= &init_net.ipv4.sysctl_raw_l3mdev_accept,
675 		.maxlen		= sizeof(int),
676 		.mode		= 0644,
677 		.proc_handler	= proc_dointvec_minmax,
678 		.extra1		= &zero,
679 		.extra2		= &one,
680 	},
681 #endif
682 	{
683 		.procname	= "tcp_ecn",
684 		.data		= &init_net.ipv4.sysctl_tcp_ecn,
685 		.maxlen		= sizeof(int),
686 		.mode		= 0644,
687 		.proc_handler	= proc_dointvec
688 	},
689 	{
690 		.procname	= "tcp_ecn_fallback",
691 		.data		= &init_net.ipv4.sysctl_tcp_ecn_fallback,
692 		.maxlen		= sizeof(int),
693 		.mode		= 0644,
694 		.proc_handler	= proc_dointvec
695 	},
696 	{
697 		.procname	= "ip_dynaddr",
698 		.data		= &init_net.ipv4.sysctl_ip_dynaddr,
699 		.maxlen		= sizeof(int),
700 		.mode		= 0644,
701 		.proc_handler	= proc_dointvec
702 	},
703 	{
704 		.procname	= "ip_early_demux",
705 		.data		= &init_net.ipv4.sysctl_ip_early_demux,
706 		.maxlen		= sizeof(int),
707 		.mode		= 0644,
708 		.proc_handler	= proc_dointvec
709 	},
710 	{
711 		.procname       = "udp_early_demux",
712 		.data           = &init_net.ipv4.sysctl_udp_early_demux,
713 		.maxlen         = sizeof(int),
714 		.mode           = 0644,
715 		.proc_handler   = proc_udp_early_demux
716 	},
717 	{
718 		.procname       = "tcp_early_demux",
719 		.data           = &init_net.ipv4.sysctl_tcp_early_demux,
720 		.maxlen         = sizeof(int),
721 		.mode           = 0644,
722 		.proc_handler   = proc_tcp_early_demux
723 	},
724 	{
725 		.procname	= "ip_default_ttl",
726 		.data		= &init_net.ipv4.sysctl_ip_default_ttl,
727 		.maxlen		= sizeof(int),
728 		.mode		= 0644,
729 		.proc_handler	= proc_dointvec_minmax,
730 		.extra1		= &ip_ttl_min,
731 		.extra2		= &ip_ttl_max,
732 	},
733 	{
734 		.procname	= "ip_local_port_range",
735 		.maxlen		= sizeof(init_net.ipv4.ip_local_ports.range),
736 		.data		= &init_net.ipv4.ip_local_ports.range,
737 		.mode		= 0644,
738 		.proc_handler	= ipv4_local_port_range,
739 	},
740 	{
741 		.procname	= "ip_local_reserved_ports",
742 		.data		= &init_net.ipv4.sysctl_local_reserved_ports,
743 		.maxlen		= 65536,
744 		.mode		= 0644,
745 		.proc_handler	= proc_do_large_bitmap,
746 	},
747 	{
748 		.procname	= "ip_no_pmtu_disc",
749 		.data		= &init_net.ipv4.sysctl_ip_no_pmtu_disc,
750 		.maxlen		= sizeof(int),
751 		.mode		= 0644,
752 		.proc_handler	= proc_dointvec
753 	},
754 	{
755 		.procname	= "ip_forward_use_pmtu",
756 		.data		= &init_net.ipv4.sysctl_ip_fwd_use_pmtu,
757 		.maxlen		= sizeof(int),
758 		.mode		= 0644,
759 		.proc_handler	= proc_dointvec,
760 	},
761 	{
762 		.procname	= "ip_forward_update_priority",
763 		.data		= &init_net.ipv4.sysctl_ip_fwd_update_priority,
764 		.maxlen		= sizeof(int),
765 		.mode		= 0644,
766 		.proc_handler   = ipv4_fwd_update_priority,
767 		.extra1		= &zero,
768 		.extra2		= &one,
769 	},
770 	{
771 		.procname	= "ip_nonlocal_bind",
772 		.data		= &init_net.ipv4.sysctl_ip_nonlocal_bind,
773 		.maxlen		= sizeof(int),
774 		.mode		= 0644,
775 		.proc_handler	= proc_dointvec
776 	},
777 	{
778 		.procname	= "fwmark_reflect",
779 		.data		= &init_net.ipv4.sysctl_fwmark_reflect,
780 		.maxlen		= sizeof(int),
781 		.mode		= 0644,
782 		.proc_handler	= proc_dointvec,
783 	},
784 	{
785 		.procname	= "tcp_fwmark_accept",
786 		.data		= &init_net.ipv4.sysctl_tcp_fwmark_accept,
787 		.maxlen		= sizeof(int),
788 		.mode		= 0644,
789 		.proc_handler	= proc_dointvec,
790 	},
791 #ifdef CONFIG_NET_L3_MASTER_DEV
792 	{
793 		.procname	= "tcp_l3mdev_accept",
794 		.data		= &init_net.ipv4.sysctl_tcp_l3mdev_accept,
795 		.maxlen		= sizeof(int),
796 		.mode		= 0644,
797 		.proc_handler	= proc_dointvec_minmax,
798 		.extra1		= &zero,
799 		.extra2		= &one,
800 	},
801 #endif
802 	{
803 		.procname	= "tcp_mtu_probing",
804 		.data		= &init_net.ipv4.sysctl_tcp_mtu_probing,
805 		.maxlen		= sizeof(int),
806 		.mode		= 0644,
807 		.proc_handler	= proc_dointvec,
808 	},
809 	{
810 		.procname	= "tcp_base_mss",
811 		.data		= &init_net.ipv4.sysctl_tcp_base_mss,
812 		.maxlen		= sizeof(int),
813 		.mode		= 0644,
814 		.proc_handler	= proc_dointvec,
815 	},
816 	{
817 		.procname	= "tcp_min_snd_mss",
818 		.data		= &init_net.ipv4.sysctl_tcp_min_snd_mss,
819 		.maxlen		= sizeof(int),
820 		.mode		= 0644,
821 		.proc_handler	= proc_dointvec_minmax,
822 		.extra1		= &tcp_min_snd_mss_min,
823 		.extra2		= &tcp_min_snd_mss_max,
824 	},
825 	{
826 		.procname	= "tcp_probe_threshold",
827 		.data		= &init_net.ipv4.sysctl_tcp_probe_threshold,
828 		.maxlen		= sizeof(int),
829 		.mode		= 0644,
830 		.proc_handler	= proc_dointvec,
831 	},
832 	{
833 		.procname	= "tcp_probe_interval",
834 		.data		= &init_net.ipv4.sysctl_tcp_probe_interval,
835 		.maxlen		= sizeof(u32),
836 		.mode		= 0644,
837 		.proc_handler	= proc_douintvec_minmax,
838 		.extra2		= &u32_max_div_HZ,
839 	},
840 	{
841 		.procname	= "igmp_link_local_mcast_reports",
842 		.data		= &init_net.ipv4.sysctl_igmp_llm_reports,
843 		.maxlen		= sizeof(int),
844 		.mode		= 0644,
845 		.proc_handler	= proc_dointvec
846 	},
847 	{
848 		.procname	= "igmp_max_memberships",
849 		.data		= &init_net.ipv4.sysctl_igmp_max_memberships,
850 		.maxlen		= sizeof(int),
851 		.mode		= 0644,
852 		.proc_handler	= proc_dointvec
853 	},
854 	{
855 		.procname	= "igmp_max_msf",
856 		.data		= &init_net.ipv4.sysctl_igmp_max_msf,
857 		.maxlen		= sizeof(int),
858 		.mode		= 0644,
859 		.proc_handler	= proc_dointvec
860 	},
861 #ifdef CONFIG_IP_MULTICAST
862 	{
863 		.procname	= "igmp_qrv",
864 		.data		= &init_net.ipv4.sysctl_igmp_qrv,
865 		.maxlen		= sizeof(int),
866 		.mode		= 0644,
867 		.proc_handler	= proc_dointvec_minmax,
868 		.extra1		= &one
869 	},
870 #endif
871 	{
872 		.procname	= "tcp_congestion_control",
873 		.data		= &init_net.ipv4.tcp_congestion_control,
874 		.mode		= 0644,
875 		.maxlen		= TCP_CA_NAME_MAX,
876 		.proc_handler	= proc_tcp_congestion_control,
877 	},
878 	{
879 		.procname	= "tcp_keepalive_time",
880 		.data		= &init_net.ipv4.sysctl_tcp_keepalive_time,
881 		.maxlen		= sizeof(int),
882 		.mode		= 0644,
883 		.proc_handler	= proc_dointvec_jiffies,
884 	},
885 	{
886 		.procname	= "tcp_keepalive_probes",
887 		.data		= &init_net.ipv4.sysctl_tcp_keepalive_probes,
888 		.maxlen		= sizeof(int),
889 		.mode		= 0644,
890 		.proc_handler	= proc_dointvec
891 	},
892 	{
893 		.procname	= "tcp_keepalive_intvl",
894 		.data		= &init_net.ipv4.sysctl_tcp_keepalive_intvl,
895 		.maxlen		= sizeof(int),
896 		.mode		= 0644,
897 		.proc_handler	= proc_dointvec_jiffies,
898 	},
899 	{
900 		.procname	= "tcp_syn_retries",
901 		.data		= &init_net.ipv4.sysctl_tcp_syn_retries,
902 		.maxlen		= sizeof(int),
903 		.mode		= 0644,
904 		.proc_handler	= proc_dointvec_minmax,
905 		.extra1		= &tcp_syn_retries_min,
906 		.extra2		= &tcp_syn_retries_max
907 	},
908 	{
909 		.procname	= "tcp_synack_retries",
910 		.data		= &init_net.ipv4.sysctl_tcp_synack_retries,
911 		.maxlen		= sizeof(int),
912 		.mode		= 0644,
913 		.proc_handler	= proc_dointvec
914 	},
915 #ifdef CONFIG_SYN_COOKIES
916 	{
917 		.procname	= "tcp_syncookies",
918 		.data		= &init_net.ipv4.sysctl_tcp_syncookies,
919 		.maxlen		= sizeof(int),
920 		.mode		= 0644,
921 		.proc_handler	= proc_dointvec
922 	},
923 #endif
924 	{
925 		.procname	= "tcp_reordering",
926 		.data		= &init_net.ipv4.sysctl_tcp_reordering,
927 		.maxlen		= sizeof(int),
928 		.mode		= 0644,
929 		.proc_handler	= proc_dointvec
930 	},
931 	{
932 		.procname	= "tcp_retries1",
933 		.data		= &init_net.ipv4.sysctl_tcp_retries1,
934 		.maxlen		= sizeof(int),
935 		.mode		= 0644,
936 		.proc_handler	= proc_dointvec_minmax,
937 		.extra2		= &tcp_retr1_max
938 	},
939 	{
940 		.procname	= "tcp_retries2",
941 		.data		= &init_net.ipv4.sysctl_tcp_retries2,
942 		.maxlen		= sizeof(int),
943 		.mode		= 0644,
944 		.proc_handler	= proc_dointvec
945 	},
946 	{
947 		.procname	= "tcp_orphan_retries",
948 		.data		= &init_net.ipv4.sysctl_tcp_orphan_retries,
949 		.maxlen		= sizeof(int),
950 		.mode		= 0644,
951 		.proc_handler	= proc_dointvec
952 	},
953 	{
954 		.procname	= "tcp_fin_timeout",
955 		.data		= &init_net.ipv4.sysctl_tcp_fin_timeout,
956 		.maxlen		= sizeof(int),
957 		.mode		= 0644,
958 		.proc_handler	= proc_dointvec_jiffies,
959 	},
960 	{
961 		.procname	= "tcp_notsent_lowat",
962 		.data		= &init_net.ipv4.sysctl_tcp_notsent_lowat,
963 		.maxlen		= sizeof(unsigned int),
964 		.mode		= 0644,
965 		.proc_handler	= proc_douintvec,
966 	},
967 	{
968 		.procname	= "tcp_tw_reuse",
969 		.data		= &init_net.ipv4.sysctl_tcp_tw_reuse,
970 		.maxlen		= sizeof(int),
971 		.mode		= 0644,
972 		.proc_handler	= proc_dointvec_minmax,
973 		.extra1		= &zero,
974 		.extra2		= &two,
975 	},
976 	{
977 		.procname	= "tcp_max_tw_buckets",
978 		.data		= &init_net.ipv4.tcp_death_row.sysctl_max_tw_buckets,
979 		.maxlen		= sizeof(int),
980 		.mode		= 0644,
981 		.proc_handler	= proc_dointvec
982 	},
983 	{
984 		.procname	= "tcp_max_syn_backlog",
985 		.data		= &init_net.ipv4.sysctl_max_syn_backlog,
986 		.maxlen		= sizeof(int),
987 		.mode		= 0644,
988 		.proc_handler	= proc_dointvec
989 	},
990 	{
991 		.procname	= "tcp_fastopen",
992 		.data		= &init_net.ipv4.sysctl_tcp_fastopen,
993 		.maxlen		= sizeof(int),
994 		.mode		= 0644,
995 		.proc_handler	= proc_dointvec,
996 	},
997 	{
998 		.procname	= "tcp_fastopen_key",
999 		.mode		= 0600,
1000 		.data		= &init_net.ipv4.sysctl_tcp_fastopen,
1001 		/* maxlen to print the list of keys in hex (*2), with dashes
1002 		 * separating doublewords and a comma in between keys.
1003 		 */
1004 		.maxlen		= ((TCP_FASTOPEN_KEY_LENGTH *
1005 				   2 * TCP_FASTOPEN_KEY_MAX) +
1006 				   (TCP_FASTOPEN_KEY_MAX * 5)),
1007 		.proc_handler	= proc_tcp_fastopen_key,
1008 	},
1009 	{
1010 		.procname	= "tcp_fastopen_blackhole_timeout_sec",
1011 		.data		= &init_net.ipv4.sysctl_tcp_fastopen_blackhole_timeout,
1012 		.maxlen		= sizeof(int),
1013 		.mode		= 0644,
1014 		.proc_handler	= proc_tfo_blackhole_detect_timeout,
1015 		.extra1		= &zero,
1016 	},
1017 #ifdef CONFIG_IP_ROUTE_MULTIPATH
1018 	{
1019 		.procname	= "fib_multipath_use_neigh",
1020 		.data		= &init_net.ipv4.sysctl_fib_multipath_use_neigh,
1021 		.maxlen		= sizeof(int),
1022 		.mode		= 0644,
1023 		.proc_handler	= proc_dointvec_minmax,
1024 		.extra1		= &zero,
1025 		.extra2		= &one,
1026 	},
1027 	{
1028 		.procname	= "fib_multipath_hash_policy",
1029 		.data		= &init_net.ipv4.sysctl_fib_multipath_hash_policy,
1030 		.maxlen		= sizeof(int),
1031 		.mode		= 0644,
1032 		.proc_handler	= proc_fib_multipath_hash_policy,
1033 		.extra1		= &zero,
1034 		.extra2		= &two,
1035 	},
1036 #endif
1037 	{
1038 		.procname	= "ip_unprivileged_port_start",
1039 		.maxlen		= sizeof(int),
1040 		.data		= &init_net.ipv4.sysctl_ip_prot_sock,
1041 		.mode		= 0644,
1042 		.proc_handler	= ipv4_privileged_ports,
1043 	},
1044 #ifdef CONFIG_NET_L3_MASTER_DEV
1045 	{
1046 		.procname	= "udp_l3mdev_accept",
1047 		.data		= &init_net.ipv4.sysctl_udp_l3mdev_accept,
1048 		.maxlen		= sizeof(int),
1049 		.mode		= 0644,
1050 		.proc_handler	= proc_dointvec_minmax,
1051 		.extra1		= &zero,
1052 		.extra2		= &one,
1053 	},
1054 #endif
1055 	{
1056 		.procname	= "tcp_sack",
1057 		.data		= &init_net.ipv4.sysctl_tcp_sack,
1058 		.maxlen		= sizeof(int),
1059 		.mode		= 0644,
1060 		.proc_handler	= proc_dointvec
1061 	},
1062 	{
1063 		.procname	= "tcp_window_scaling",
1064 		.data		= &init_net.ipv4.sysctl_tcp_window_scaling,
1065 		.maxlen		= sizeof(int),
1066 		.mode		= 0644,
1067 		.proc_handler	= proc_dointvec
1068 	},
1069 	{
1070 		.procname	= "tcp_timestamps",
1071 		.data		= &init_net.ipv4.sysctl_tcp_timestamps,
1072 		.maxlen		= sizeof(int),
1073 		.mode		= 0644,
1074 		.proc_handler	= proc_dointvec
1075 	},
1076 	{
1077 		.procname	= "tcp_early_retrans",
1078 		.data		= &init_net.ipv4.sysctl_tcp_early_retrans,
1079 		.maxlen		= sizeof(int),
1080 		.mode		= 0644,
1081 		.proc_handler	= proc_dointvec_minmax,
1082 		.extra1		= &zero,
1083 		.extra2		= &four,
1084 	},
1085 	{
1086 		.procname	= "tcp_recovery",
1087 		.data		= &init_net.ipv4.sysctl_tcp_recovery,
1088 		.maxlen		= sizeof(int),
1089 		.mode		= 0644,
1090 		.proc_handler	= proc_dointvec,
1091 	},
1092 	{
1093 		.procname       = "tcp_thin_linear_timeouts",
1094 		.data           = &init_net.ipv4.sysctl_tcp_thin_linear_timeouts,
1095 		.maxlen         = sizeof(int),
1096 		.mode           = 0644,
1097 		.proc_handler   = proc_dointvec
1098 	},
1099 	{
1100 		.procname	= "tcp_slow_start_after_idle",
1101 		.data		= &init_net.ipv4.sysctl_tcp_slow_start_after_idle,
1102 		.maxlen		= sizeof(int),
1103 		.mode		= 0644,
1104 		.proc_handler	= proc_dointvec
1105 	},
1106 	{
1107 		.procname	= "tcp_retrans_collapse",
1108 		.data		= &init_net.ipv4.sysctl_tcp_retrans_collapse,
1109 		.maxlen		= sizeof(int),
1110 		.mode		= 0644,
1111 		.proc_handler	= proc_dointvec
1112 	},
1113 	{
1114 		.procname	= "tcp_stdurg",
1115 		.data		= &init_net.ipv4.sysctl_tcp_stdurg,
1116 		.maxlen		= sizeof(int),
1117 		.mode		= 0644,
1118 		.proc_handler	= proc_dointvec
1119 	},
1120 	{
1121 		.procname	= "tcp_rfc1337",
1122 		.data		= &init_net.ipv4.sysctl_tcp_rfc1337,
1123 		.maxlen		= sizeof(int),
1124 		.mode		= 0644,
1125 		.proc_handler	= proc_dointvec
1126 	},
1127 	{
1128 		.procname	= "tcp_abort_on_overflow",
1129 		.data		= &init_net.ipv4.sysctl_tcp_abort_on_overflow,
1130 		.maxlen		= sizeof(int),
1131 		.mode		= 0644,
1132 		.proc_handler	= proc_dointvec
1133 	},
1134 	{
1135 		.procname	= "tcp_fack",
1136 		.data		= &init_net.ipv4.sysctl_tcp_fack,
1137 		.maxlen		= sizeof(int),
1138 		.mode		= 0644,
1139 		.proc_handler	= proc_dointvec
1140 	},
1141 	{
1142 		.procname	= "tcp_max_reordering",
1143 		.data		= &init_net.ipv4.sysctl_tcp_max_reordering,
1144 		.maxlen		= sizeof(int),
1145 		.mode		= 0644,
1146 		.proc_handler	= proc_dointvec
1147 	},
1148 	{
1149 		.procname	= "tcp_dsack",
1150 		.data		= &init_net.ipv4.sysctl_tcp_dsack,
1151 		.maxlen		= sizeof(int),
1152 		.mode		= 0644,
1153 		.proc_handler	= proc_dointvec
1154 	},
1155 	{
1156 		.procname	= "tcp_app_win",
1157 		.data		= &init_net.ipv4.sysctl_tcp_app_win,
1158 		.maxlen		= sizeof(int),
1159 		.mode		= 0644,
1160 		.proc_handler	= proc_dointvec
1161 	},
1162 	{
1163 		.procname	= "tcp_adv_win_scale",
1164 		.data		= &init_net.ipv4.sysctl_tcp_adv_win_scale,
1165 		.maxlen		= sizeof(int),
1166 		.mode		= 0644,
1167 		.proc_handler	= proc_dointvec_minmax,
1168 		.extra1		= &tcp_adv_win_scale_min,
1169 		.extra2		= &tcp_adv_win_scale_max,
1170 	},
1171 	{
1172 		.procname	= "tcp_frto",
1173 		.data		= &init_net.ipv4.sysctl_tcp_frto,
1174 		.maxlen		= sizeof(int),
1175 		.mode		= 0644,
1176 		.proc_handler	= proc_dointvec
1177 	},
1178 	{
1179 		.procname	= "tcp_no_metrics_save",
1180 		.data		= &init_net.ipv4.sysctl_tcp_nometrics_save,
1181 		.maxlen		= sizeof(int),
1182 		.mode		= 0644,
1183 		.proc_handler	= proc_dointvec,
1184 	},
1185 	{
1186 		.procname	= "tcp_moderate_rcvbuf",
1187 		.data		= &init_net.ipv4.sysctl_tcp_moderate_rcvbuf,
1188 		.maxlen		= sizeof(int),
1189 		.mode		= 0644,
1190 		.proc_handler	= proc_dointvec,
1191 	},
1192 	{
1193 		.procname	= "tcp_tso_win_divisor",
1194 		.data		= &init_net.ipv4.sysctl_tcp_tso_win_divisor,
1195 		.maxlen		= sizeof(int),
1196 		.mode		= 0644,
1197 		.proc_handler	= proc_dointvec,
1198 	},
1199 	{
1200 		.procname	= "tcp_workaround_signed_windows",
1201 		.data		= &init_net.ipv4.sysctl_tcp_workaround_signed_windows,
1202 		.maxlen		= sizeof(int),
1203 		.mode		= 0644,
1204 		.proc_handler	= proc_dointvec
1205 	},
1206 	{
1207 		.procname	= "tcp_limit_output_bytes",
1208 		.data		= &init_net.ipv4.sysctl_tcp_limit_output_bytes,
1209 		.maxlen		= sizeof(int),
1210 		.mode		= 0644,
1211 		.proc_handler	= proc_dointvec
1212 	},
1213 	{
1214 		.procname	= "tcp_challenge_ack_limit",
1215 		.data		= &init_net.ipv4.sysctl_tcp_challenge_ack_limit,
1216 		.maxlen		= sizeof(int),
1217 		.mode		= 0644,
1218 		.proc_handler	= proc_dointvec
1219 	},
1220 	{
1221 		.procname	= "tcp_min_tso_segs",
1222 		.data		= &init_net.ipv4.sysctl_tcp_min_tso_segs,
1223 		.maxlen		= sizeof(int),
1224 		.mode		= 0644,
1225 		.proc_handler	= proc_dointvec_minmax,
1226 		.extra1		= &one,
1227 		.extra2		= &gso_max_segs,
1228 	},
1229 	{
1230 		.procname	= "tcp_min_rtt_wlen",
1231 		.data		= &init_net.ipv4.sysctl_tcp_min_rtt_wlen,
1232 		.maxlen		= sizeof(int),
1233 		.mode		= 0644,
1234 		.proc_handler	= proc_dointvec_minmax,
1235 		.extra1		= &zero,
1236 		.extra2		= &one_day_secs
1237 	},
1238 	{
1239 		.procname	= "tcp_autocorking",
1240 		.data		= &init_net.ipv4.sysctl_tcp_autocorking,
1241 		.maxlen		= sizeof(int),
1242 		.mode		= 0644,
1243 		.proc_handler	= proc_dointvec_minmax,
1244 		.extra1		= &zero,
1245 		.extra2		= &one,
1246 	},
1247 	{
1248 		.procname	= "tcp_invalid_ratelimit",
1249 		.data		= &init_net.ipv4.sysctl_tcp_invalid_ratelimit,
1250 		.maxlen		= sizeof(int),
1251 		.mode		= 0644,
1252 		.proc_handler	= proc_dointvec_ms_jiffies,
1253 	},
1254 	{
1255 		.procname	= "tcp_pacing_ss_ratio",
1256 		.data		= &init_net.ipv4.sysctl_tcp_pacing_ss_ratio,
1257 		.maxlen		= sizeof(int),
1258 		.mode		= 0644,
1259 		.proc_handler	= proc_dointvec_minmax,
1260 		.extra1		= &zero,
1261 		.extra2		= &thousand,
1262 	},
1263 	{
1264 		.procname	= "tcp_pacing_ca_ratio",
1265 		.data		= &init_net.ipv4.sysctl_tcp_pacing_ca_ratio,
1266 		.maxlen		= sizeof(int),
1267 		.mode		= 0644,
1268 		.proc_handler	= proc_dointvec_minmax,
1269 		.extra1		= &zero,
1270 		.extra2		= &thousand,
1271 	},
1272 	{
1273 		.procname	= "tcp_wmem",
1274 		.data		= &init_net.ipv4.sysctl_tcp_wmem,
1275 		.maxlen		= sizeof(init_net.ipv4.sysctl_tcp_wmem),
1276 		.mode		= 0644,
1277 		.proc_handler	= proc_dointvec_minmax,
1278 		.extra1		= &one,
1279 	},
1280 	{
1281 		.procname	= "tcp_rmem",
1282 		.data		= &init_net.ipv4.sysctl_tcp_rmem,
1283 		.maxlen		= sizeof(init_net.ipv4.sysctl_tcp_rmem),
1284 		.mode		= 0644,
1285 		.proc_handler	= proc_dointvec_minmax,
1286 		.extra1		= &one,
1287 	},
1288 	{
1289 		.procname	= "tcp_comp_sack_delay_ns",
1290 		.data		= &init_net.ipv4.sysctl_tcp_comp_sack_delay_ns,
1291 		.maxlen		= sizeof(unsigned long),
1292 		.mode		= 0644,
1293 		.proc_handler	= proc_doulongvec_minmax,
1294 	},
1295 	{
1296 		.procname	= "tcp_comp_sack_nr",
1297 		.data		= &init_net.ipv4.sysctl_tcp_comp_sack_nr,
1298 		.maxlen		= sizeof(int),
1299 		.mode		= 0644,
1300 		.proc_handler	= proc_dointvec_minmax,
1301 		.extra1		= &zero,
1302 		.extra2		= &comp_sack_nr_max,
1303 	},
1304 	{
1305 		.procname	= "udp_rmem_min",
1306 		.data		= &init_net.ipv4.sysctl_udp_rmem_min,
1307 		.maxlen		= sizeof(init_net.ipv4.sysctl_udp_rmem_min),
1308 		.mode		= 0644,
1309 		.proc_handler	= proc_dointvec_minmax,
1310 		.extra1		= &one
1311 	},
1312 	{
1313 		.procname	= "udp_wmem_min",
1314 		.data		= &init_net.ipv4.sysctl_udp_wmem_min,
1315 		.maxlen		= sizeof(init_net.ipv4.sysctl_udp_wmem_min),
1316 		.mode		= 0644,
1317 		.proc_handler	= proc_dointvec_minmax,
1318 		.extra1		= &one
1319 	},
1320 	{ }
1321 };
1322 
1323 static __net_init int ipv4_sysctl_init_net(struct net *net)
1324 {
1325 	struct ctl_table *table;
1326 
1327 	table = ipv4_net_table;
1328 	if (!net_eq(net, &init_net)) {
1329 		int i;
1330 
1331 		table = kmemdup(table, sizeof(ipv4_net_table), GFP_KERNEL);
1332 		if (!table)
1333 			goto err_alloc;
1334 
1335 		/* Update the variables to point into the current struct net */
1336 		for (i = 0; i < ARRAY_SIZE(ipv4_net_table) - 1; i++)
1337 			table[i].data += (void *)net - (void *)&init_net;
1338 	}
1339 
1340 	net->ipv4.ipv4_hdr = register_net_sysctl(net, "net/ipv4", table);
1341 	if (!net->ipv4.ipv4_hdr)
1342 		goto err_reg;
1343 
1344 	net->ipv4.sysctl_local_reserved_ports = kzalloc(65536 / 8, GFP_KERNEL);
1345 	if (!net->ipv4.sysctl_local_reserved_ports)
1346 		goto err_ports;
1347 
1348 	return 0;
1349 
1350 err_ports:
1351 	unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
1352 err_reg:
1353 	if (!net_eq(net, &init_net))
1354 		kfree(table);
1355 err_alloc:
1356 	return -ENOMEM;
1357 }
1358 
1359 static __net_exit void ipv4_sysctl_exit_net(struct net *net)
1360 {
1361 	struct ctl_table *table;
1362 
1363 	kfree(net->ipv4.sysctl_local_reserved_ports);
1364 	table = net->ipv4.ipv4_hdr->ctl_table_arg;
1365 	unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
1366 	kfree(table);
1367 }
1368 
1369 static __net_initdata struct pernet_operations ipv4_sysctl_ops = {
1370 	.init = ipv4_sysctl_init_net,
1371 	.exit = ipv4_sysctl_exit_net,
1372 };
1373 
1374 static __init int sysctl_ipv4_init(void)
1375 {
1376 	struct ctl_table_header *hdr;
1377 
1378 	hdr = register_net_sysctl(&init_net, "net/ipv4", ipv4_table);
1379 	if (!hdr)
1380 		return -ENOMEM;
1381 
1382 	if (register_pernet_subsys(&ipv4_sysctl_ops)) {
1383 		unregister_net_sysctl_table(hdr);
1384 		return -ENOMEM;
1385 	}
1386 
1387 	return 0;
1388 }
1389 
1390 __initcall(sysctl_ipv4_init);
1391