xref: /linux/net/ipv4/sysctl_net_ipv4.c (revision f898c16a0624e7f2dcb0b1cda6916c9be6489197)
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/sysctl.h>
10 #include <linux/seqlock.h>
11 #include <linux/init.h>
12 #include <linux/slab.h>
13 #include <net/icmp.h>
14 #include <net/ip.h>
15 #include <net/ip_fib.h>
16 #include <net/tcp.h>
17 #include <net/udp.h>
18 #include <net/cipso_ipv4.h>
19 #include <net/ping.h>
20 #include <net/protocol.h>
21 #include <net/netevent.h>
22 
23 static int tcp_retr1_max = 255;
24 static int ip_local_port_range_min[] = { 1, 1 };
25 static int ip_local_port_range_max[] = { 65535, 65535 };
26 static int tcp_adv_win_scale_min = -31;
27 static int tcp_adv_win_scale_max = 31;
28 static int tcp_app_win_max = 31;
29 static int tcp_min_snd_mss_min = TCP_MIN_SND_MSS;
30 static int tcp_min_snd_mss_max = 65535;
31 static int ip_privileged_port_min;
32 static int ip_privileged_port_max = 65535;
33 static int ip_ttl_min = 1;
34 static int ip_ttl_max = 255;
35 static int tcp_syn_retries_min = 1;
36 static int tcp_syn_retries_max = MAX_TCP_SYNCNT;
37 static int tcp_syn_linear_timeouts_max = MAX_TCP_SYNCNT;
38 static unsigned long ip_ping_group_range_min[] = { 0, 0 };
39 static unsigned long ip_ping_group_range_max[] = { GID_T_MAX, GID_T_MAX };
40 static u32 u32_max_div_HZ = UINT_MAX / HZ;
41 static int one_day_secs = 24 * 3600;
42 static u32 fib_multipath_hash_fields_all_mask __maybe_unused =
43 	FIB_MULTIPATH_HASH_FIELD_ALL_MASK;
44 static unsigned int tcp_child_ehash_entries_max = 16 * 1024 * 1024;
45 static unsigned int udp_child_hash_entries_max = UDP_HTABLE_SIZE_MAX;
46 static int tcp_plb_max_rounds = 31;
47 static int tcp_plb_max_cong_thresh = 256;
48 
49 /* obsolete */
50 static int sysctl_tcp_low_latency __read_mostly;
51 
52 /* Update system visible IP port range */
53 static void set_local_port_range(struct net *net, unsigned int low, unsigned int high)
54 {
55 	bool same_parity = !((low ^ high) & 1);
56 
57 	if (same_parity && !net->ipv4.ip_local_ports.warned) {
58 		net->ipv4.ip_local_ports.warned = true;
59 		pr_err_ratelimited("ip_local_port_range: prefer different parity for start/end values.\n");
60 	}
61 	WRITE_ONCE(net->ipv4.ip_local_ports.range, high << 16 | low);
62 }
63 
64 /* Validate changes from /proc interface. */
65 static int ipv4_local_port_range(struct ctl_table *table, int write,
66 				 void *buffer, size_t *lenp, loff_t *ppos)
67 {
68 	struct net *net = table->data;
69 	int ret;
70 	int range[2];
71 	struct ctl_table tmp = {
72 		.data = &range,
73 		.maxlen = sizeof(range),
74 		.mode = table->mode,
75 		.extra1 = &ip_local_port_range_min,
76 		.extra2 = &ip_local_port_range_max,
77 	};
78 
79 	inet_get_local_port_range(net, &range[0], &range[1]);
80 
81 	ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
82 
83 	if (write && ret == 0) {
84 		/* Ensure that the upper limit is not smaller than the lower,
85 		 * and that the lower does not encroach upon the privileged
86 		 * port limit.
87 		 */
88 		if ((range[1] < range[0]) ||
89 		    (range[0] < READ_ONCE(net->ipv4.sysctl_ip_prot_sock)))
90 			ret = -EINVAL;
91 		else
92 			set_local_port_range(net, range[0], range[1]);
93 	}
94 
95 	return ret;
96 }
97 
98 /* Validate changes from /proc interface. */
99 static int ipv4_privileged_ports(struct ctl_table *table, int write,
100 				void *buffer, size_t *lenp, loff_t *ppos)
101 {
102 	struct net *net = container_of(table->data, struct net,
103 	    ipv4.sysctl_ip_prot_sock);
104 	int ret;
105 	int pports;
106 	int range[2];
107 	struct ctl_table tmp = {
108 		.data = &pports,
109 		.maxlen = sizeof(pports),
110 		.mode = table->mode,
111 		.extra1 = &ip_privileged_port_min,
112 		.extra2 = &ip_privileged_port_max,
113 	};
114 
115 	pports = READ_ONCE(net->ipv4.sysctl_ip_prot_sock);
116 
117 	ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
118 
119 	if (write && ret == 0) {
120 		inet_get_local_port_range(net, &range[0], &range[1]);
121 		/* Ensure that the local port range doesn't overlap with the
122 		 * privileged port range.
123 		 */
124 		if (range[0] < pports)
125 			ret = -EINVAL;
126 		else
127 			WRITE_ONCE(net->ipv4.sysctl_ip_prot_sock, pports);
128 	}
129 
130 	return ret;
131 }
132 
133 static void inet_get_ping_group_range_table(const struct ctl_table *table,
134 					    kgid_t *low, kgid_t *high)
135 {
136 	kgid_t *data = table->data;
137 	struct net *net =
138 		container_of(table->data, struct net, ipv4.ping_group_range.range);
139 	unsigned int seq;
140 	do {
141 		seq = read_seqbegin(&net->ipv4.ping_group_range.lock);
142 
143 		*low = data[0];
144 		*high = data[1];
145 	} while (read_seqretry(&net->ipv4.ping_group_range.lock, seq));
146 }
147 
148 /* Update system visible IP port range */
149 static void set_ping_group_range(const struct ctl_table *table,
150 				 kgid_t low, kgid_t high)
151 {
152 	kgid_t *data = table->data;
153 	struct net *net =
154 		container_of(table->data, struct net, ipv4.ping_group_range.range);
155 	write_seqlock(&net->ipv4.ping_group_range.lock);
156 	data[0] = low;
157 	data[1] = high;
158 	write_sequnlock(&net->ipv4.ping_group_range.lock);
159 }
160 
161 /* Validate changes from /proc interface. */
162 static int ipv4_ping_group_range(struct ctl_table *table, int write,
163 				 void *buffer, size_t *lenp, loff_t *ppos)
164 {
165 	struct user_namespace *user_ns = current_user_ns();
166 	int ret;
167 	unsigned long urange[2];
168 	kgid_t low, high;
169 	struct ctl_table tmp = {
170 		.data = &urange,
171 		.maxlen = sizeof(urange),
172 		.mode = table->mode,
173 		.extra1 = &ip_ping_group_range_min,
174 		.extra2 = &ip_ping_group_range_max,
175 	};
176 
177 	inet_get_ping_group_range_table(table, &low, &high);
178 	urange[0] = from_kgid_munged(user_ns, low);
179 	urange[1] = from_kgid_munged(user_ns, high);
180 	ret = proc_doulongvec_minmax(&tmp, write, buffer, lenp, ppos);
181 
182 	if (write && ret == 0) {
183 		low = make_kgid(user_ns, urange[0]);
184 		high = make_kgid(user_ns, urange[1]);
185 		if (!gid_valid(low) || !gid_valid(high))
186 			return -EINVAL;
187 		if (urange[1] < urange[0] || gid_lt(high, low)) {
188 			low = make_kgid(&init_user_ns, 1);
189 			high = make_kgid(&init_user_ns, 0);
190 		}
191 		set_ping_group_range(table, low, high);
192 	}
193 
194 	return ret;
195 }
196 
197 static int ipv4_fwd_update_priority(struct ctl_table *table, int write,
198 				    void *buffer, size_t *lenp, loff_t *ppos)
199 {
200 	struct net *net;
201 	int ret;
202 
203 	net = container_of(table->data, struct net,
204 			   ipv4.sysctl_ip_fwd_update_priority);
205 	ret = proc_dou8vec_minmax(table, write, buffer, lenp, ppos);
206 	if (write && ret == 0)
207 		call_netevent_notifiers(NETEVENT_IPV4_FWD_UPDATE_PRIORITY_UPDATE,
208 					net);
209 
210 	return ret;
211 }
212 
213 static int proc_tcp_congestion_control(struct ctl_table *ctl, int write,
214 				       void *buffer, size_t *lenp, loff_t *ppos)
215 {
216 	struct net *net = container_of(ctl->data, struct net,
217 				       ipv4.tcp_congestion_control);
218 	char val[TCP_CA_NAME_MAX];
219 	struct ctl_table tbl = {
220 		.data = val,
221 		.maxlen = TCP_CA_NAME_MAX,
222 	};
223 	int ret;
224 
225 	tcp_get_default_congestion_control(net, val);
226 
227 	ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
228 	if (write && ret == 0)
229 		ret = tcp_set_default_congestion_control(net, val);
230 	return ret;
231 }
232 
233 static int proc_tcp_available_congestion_control(struct ctl_table *ctl,
234 						 int write, void *buffer,
235 						 size_t *lenp, loff_t *ppos)
236 {
237 	struct ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX, };
238 	int ret;
239 
240 	tbl.data = kmalloc(tbl.maxlen, GFP_USER);
241 	if (!tbl.data)
242 		return -ENOMEM;
243 	tcp_get_available_congestion_control(tbl.data, TCP_CA_BUF_MAX);
244 	ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
245 	kfree(tbl.data);
246 	return ret;
247 }
248 
249 static int proc_allowed_congestion_control(struct ctl_table *ctl,
250 					   int write, void *buffer,
251 					   size_t *lenp, loff_t *ppos)
252 {
253 	struct ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX };
254 	int ret;
255 
256 	tbl.data = kmalloc(tbl.maxlen, GFP_USER);
257 	if (!tbl.data)
258 		return -ENOMEM;
259 
260 	tcp_get_allowed_congestion_control(tbl.data, tbl.maxlen);
261 	ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
262 	if (write && ret == 0)
263 		ret = tcp_set_allowed_congestion_control(tbl.data);
264 	kfree(tbl.data);
265 	return ret;
266 }
267 
268 static int sscanf_key(char *buf, __le32 *key)
269 {
270 	u32 user_key[4];
271 	int i, ret = 0;
272 
273 	if (sscanf(buf, "%x-%x-%x-%x", user_key, user_key + 1,
274 		   user_key + 2, user_key + 3) != 4) {
275 		ret = -EINVAL;
276 	} else {
277 		for (i = 0; i < ARRAY_SIZE(user_key); i++)
278 			key[i] = cpu_to_le32(user_key[i]);
279 	}
280 	pr_debug("proc TFO key set 0x%x-%x-%x-%x <- 0x%s: %u\n",
281 		 user_key[0], user_key[1], user_key[2], user_key[3], buf, ret);
282 
283 	return ret;
284 }
285 
286 static int proc_tcp_fastopen_key(struct ctl_table *table, int write,
287 				 void *buffer, size_t *lenp, loff_t *ppos)
288 {
289 	struct net *net = container_of(table->data, struct net,
290 	    ipv4.sysctl_tcp_fastopen);
291 	/* maxlen to print the list of keys in hex (*2), with dashes
292 	 * separating doublewords and a comma in between keys.
293 	 */
294 	struct ctl_table tbl = { .maxlen = ((TCP_FASTOPEN_KEY_LENGTH *
295 					    2 * TCP_FASTOPEN_KEY_MAX) +
296 					    (TCP_FASTOPEN_KEY_MAX * 5)) };
297 	u32 user_key[TCP_FASTOPEN_KEY_BUF_LENGTH / sizeof(u32)];
298 	__le32 key[TCP_FASTOPEN_KEY_BUF_LENGTH / sizeof(__le32)];
299 	char *backup_data;
300 	int ret, i = 0, off = 0, n_keys;
301 
302 	tbl.data = kmalloc(tbl.maxlen, GFP_KERNEL);
303 	if (!tbl.data)
304 		return -ENOMEM;
305 
306 	n_keys = tcp_fastopen_get_cipher(net, NULL, (u64 *)key);
307 	if (!n_keys) {
308 		memset(&key[0], 0, TCP_FASTOPEN_KEY_LENGTH);
309 		n_keys = 1;
310 	}
311 
312 	for (i = 0; i < n_keys * 4; i++)
313 		user_key[i] = le32_to_cpu(key[i]);
314 
315 	for (i = 0; i < n_keys; i++) {
316 		off += snprintf(tbl.data + off, tbl.maxlen - off,
317 				"%08x-%08x-%08x-%08x",
318 				user_key[i * 4],
319 				user_key[i * 4 + 1],
320 				user_key[i * 4 + 2],
321 				user_key[i * 4 + 3]);
322 
323 		if (WARN_ON_ONCE(off >= tbl.maxlen - 1))
324 			break;
325 
326 		if (i + 1 < n_keys)
327 			off += snprintf(tbl.data + off, tbl.maxlen - off, ",");
328 	}
329 
330 	ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
331 
332 	if (write && ret == 0) {
333 		backup_data = strchr(tbl.data, ',');
334 		if (backup_data) {
335 			*backup_data = '\0';
336 			backup_data++;
337 		}
338 		if (sscanf_key(tbl.data, key)) {
339 			ret = -EINVAL;
340 			goto bad_key;
341 		}
342 		if (backup_data) {
343 			if (sscanf_key(backup_data, key + 4)) {
344 				ret = -EINVAL;
345 				goto bad_key;
346 			}
347 		}
348 		tcp_fastopen_reset_cipher(net, NULL, key,
349 					  backup_data ? key + 4 : NULL);
350 	}
351 
352 bad_key:
353 	kfree(tbl.data);
354 	return ret;
355 }
356 
357 static int proc_tfo_blackhole_detect_timeout(struct ctl_table *table,
358 					     int write, void *buffer,
359 					     size_t *lenp, loff_t *ppos)
360 {
361 	struct net *net = container_of(table->data, struct net,
362 	    ipv4.sysctl_tcp_fastopen_blackhole_timeout);
363 	int ret;
364 
365 	ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
366 	if (write && ret == 0)
367 		atomic_set(&net->ipv4.tfo_active_disable_times, 0);
368 
369 	return ret;
370 }
371 
372 static int proc_tcp_available_ulp(struct ctl_table *ctl,
373 				  int write, void *buffer, size_t *lenp,
374 				  loff_t *ppos)
375 {
376 	struct ctl_table tbl = { .maxlen = TCP_ULP_BUF_MAX, };
377 	int ret;
378 
379 	tbl.data = kmalloc(tbl.maxlen, GFP_USER);
380 	if (!tbl.data)
381 		return -ENOMEM;
382 	tcp_get_available_ulp(tbl.data, TCP_ULP_BUF_MAX);
383 	ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
384 	kfree(tbl.data);
385 
386 	return ret;
387 }
388 
389 static int proc_tcp_ehash_entries(struct ctl_table *table, int write,
390 				  void *buffer, size_t *lenp, loff_t *ppos)
391 {
392 	struct net *net = container_of(table->data, struct net,
393 				       ipv4.sysctl_tcp_child_ehash_entries);
394 	struct inet_hashinfo *hinfo = net->ipv4.tcp_death_row.hashinfo;
395 	int tcp_ehash_entries;
396 	struct ctl_table tbl;
397 
398 	tcp_ehash_entries = hinfo->ehash_mask + 1;
399 
400 	/* A negative number indicates that the child netns
401 	 * shares the global ehash.
402 	 */
403 	if (!net_eq(net, &init_net) && !hinfo->pernet)
404 		tcp_ehash_entries *= -1;
405 
406 	memset(&tbl, 0, sizeof(tbl));
407 	tbl.data = &tcp_ehash_entries;
408 	tbl.maxlen = sizeof(int);
409 
410 	return proc_dointvec(&tbl, write, buffer, lenp, ppos);
411 }
412 
413 static int proc_udp_hash_entries(struct ctl_table *table, int write,
414 				 void *buffer, size_t *lenp, loff_t *ppos)
415 {
416 	struct net *net = container_of(table->data, struct net,
417 				       ipv4.sysctl_udp_child_hash_entries);
418 	int udp_hash_entries;
419 	struct ctl_table tbl;
420 
421 	udp_hash_entries = net->ipv4.udp_table->mask + 1;
422 
423 	/* A negative number indicates that the child netns
424 	 * shares the global udp_table.
425 	 */
426 	if (!net_eq(net, &init_net) && net->ipv4.udp_table == &udp_table)
427 		udp_hash_entries *= -1;
428 
429 	memset(&tbl, 0, sizeof(tbl));
430 	tbl.data = &udp_hash_entries;
431 	tbl.maxlen = sizeof(int);
432 
433 	return proc_dointvec(&tbl, write, buffer, lenp, ppos);
434 }
435 
436 #ifdef CONFIG_IP_ROUTE_MULTIPATH
437 static int proc_fib_multipath_hash_policy(struct ctl_table *table, int write,
438 					  void *buffer, size_t *lenp,
439 					  loff_t *ppos)
440 {
441 	struct net *net = container_of(table->data, struct net,
442 	    ipv4.sysctl_fib_multipath_hash_policy);
443 	int ret;
444 
445 	ret = proc_dou8vec_minmax(table, write, buffer, lenp, ppos);
446 	if (write && ret == 0)
447 		call_netevent_notifiers(NETEVENT_IPV4_MPATH_HASH_UPDATE, net);
448 
449 	return ret;
450 }
451 
452 static int proc_fib_multipath_hash_fields(struct ctl_table *table, int write,
453 					  void *buffer, size_t *lenp,
454 					  loff_t *ppos)
455 {
456 	struct net *net;
457 	int ret;
458 
459 	net = container_of(table->data, struct net,
460 			   ipv4.sysctl_fib_multipath_hash_fields);
461 	ret = proc_douintvec_minmax(table, write, buffer, lenp, ppos);
462 	if (write && ret == 0)
463 		call_netevent_notifiers(NETEVENT_IPV4_MPATH_HASH_UPDATE, net);
464 
465 	return ret;
466 }
467 
468 static u32 proc_fib_multipath_hash_rand_seed __ro_after_init;
469 
470 static void proc_fib_multipath_hash_init_rand_seed(void)
471 {
472 	get_random_bytes(&proc_fib_multipath_hash_rand_seed,
473 			 sizeof(proc_fib_multipath_hash_rand_seed));
474 }
475 
476 static void proc_fib_multipath_hash_set_seed(struct net *net, u32 user_seed)
477 {
478 	struct sysctl_fib_multipath_hash_seed new = {
479 		.user_seed = user_seed,
480 		.mp_seed = (user_seed ? user_seed :
481 			    proc_fib_multipath_hash_rand_seed),
482 	};
483 
484 	WRITE_ONCE(net->ipv4.sysctl_fib_multipath_hash_seed, new);
485 }
486 
487 static int proc_fib_multipath_hash_seed(struct ctl_table *table, int write,
488 					void *buffer, size_t *lenp,
489 					loff_t *ppos)
490 {
491 	struct sysctl_fib_multipath_hash_seed *mphs;
492 	struct net *net = table->data;
493 	struct ctl_table tmp;
494 	u32 user_seed;
495 	int ret;
496 
497 	mphs = &net->ipv4.sysctl_fib_multipath_hash_seed;
498 	user_seed = mphs->user_seed;
499 
500 	tmp = *table;
501 	tmp.data = &user_seed;
502 
503 	ret = proc_douintvec_minmax(&tmp, write, buffer, lenp, ppos);
504 
505 	if (write && ret == 0) {
506 		proc_fib_multipath_hash_set_seed(net, user_seed);
507 		call_netevent_notifiers(NETEVENT_IPV4_MPATH_HASH_UPDATE, net);
508 	}
509 
510 	return ret;
511 }
512 #else
513 
514 static void proc_fib_multipath_hash_init_rand_seed(void)
515 {
516 }
517 
518 static void proc_fib_multipath_hash_set_seed(struct net *net, u32 user_seed)
519 {
520 }
521 
522 #endif
523 
524 static struct ctl_table ipv4_table[] = {
525 	{
526 		.procname	= "tcp_max_orphans",
527 		.data		= &sysctl_tcp_max_orphans,
528 		.maxlen		= sizeof(int),
529 		.mode		= 0644,
530 		.proc_handler	= proc_dointvec
531 	},
532 	{
533 		.procname	= "inet_peer_threshold",
534 		.data		= &inet_peer_threshold,
535 		.maxlen		= sizeof(int),
536 		.mode		= 0644,
537 		.proc_handler	= proc_dointvec
538 	},
539 	{
540 		.procname	= "inet_peer_minttl",
541 		.data		= &inet_peer_minttl,
542 		.maxlen		= sizeof(int),
543 		.mode		= 0644,
544 		.proc_handler	= proc_dointvec_jiffies,
545 	},
546 	{
547 		.procname	= "inet_peer_maxttl",
548 		.data		= &inet_peer_maxttl,
549 		.maxlen		= sizeof(int),
550 		.mode		= 0644,
551 		.proc_handler	= proc_dointvec_jiffies,
552 	},
553 	{
554 		.procname	= "tcp_mem",
555 		.maxlen		= sizeof(sysctl_tcp_mem),
556 		.data		= &sysctl_tcp_mem,
557 		.mode		= 0644,
558 		.proc_handler	= proc_doulongvec_minmax,
559 	},
560 	{
561 		.procname	= "tcp_low_latency",
562 		.data		= &sysctl_tcp_low_latency,
563 		.maxlen		= sizeof(int),
564 		.mode		= 0644,
565 		.proc_handler	= proc_dointvec
566 	},
567 #ifdef CONFIG_NETLABEL
568 	{
569 		.procname	= "cipso_cache_enable",
570 		.data		= &cipso_v4_cache_enabled,
571 		.maxlen		= sizeof(int),
572 		.mode		= 0644,
573 		.proc_handler	= proc_dointvec,
574 	},
575 	{
576 		.procname	= "cipso_cache_bucket_size",
577 		.data		= &cipso_v4_cache_bucketsize,
578 		.maxlen		= sizeof(int),
579 		.mode		= 0644,
580 		.proc_handler	= proc_dointvec,
581 	},
582 	{
583 		.procname	= "cipso_rbm_optfmt",
584 		.data		= &cipso_v4_rbm_optfmt,
585 		.maxlen		= sizeof(int),
586 		.mode		= 0644,
587 		.proc_handler	= proc_dointvec,
588 	},
589 	{
590 		.procname	= "cipso_rbm_strictvalid",
591 		.data		= &cipso_v4_rbm_strictvalid,
592 		.maxlen		= sizeof(int),
593 		.mode		= 0644,
594 		.proc_handler	= proc_dointvec,
595 	},
596 #endif /* CONFIG_NETLABEL */
597 	{
598 		.procname	= "tcp_available_ulp",
599 		.maxlen		= TCP_ULP_BUF_MAX,
600 		.mode		= 0444,
601 		.proc_handler   = proc_tcp_available_ulp,
602 	},
603 	{
604 		.procname	= "icmp_msgs_per_sec",
605 		.data		= &sysctl_icmp_msgs_per_sec,
606 		.maxlen		= sizeof(int),
607 		.mode		= 0644,
608 		.proc_handler	= proc_dointvec_minmax,
609 		.extra1		= SYSCTL_ZERO,
610 	},
611 	{
612 		.procname	= "icmp_msgs_burst",
613 		.data		= &sysctl_icmp_msgs_burst,
614 		.maxlen		= sizeof(int),
615 		.mode		= 0644,
616 		.proc_handler	= proc_dointvec_minmax,
617 		.extra1		= SYSCTL_ZERO,
618 	},
619 	{
620 		.procname	= "udp_mem",
621 		.data		= &sysctl_udp_mem,
622 		.maxlen		= sizeof(sysctl_udp_mem),
623 		.mode		= 0644,
624 		.proc_handler	= proc_doulongvec_minmax,
625 	},
626 	{
627 		.procname	= "fib_sync_mem",
628 		.data		= &sysctl_fib_sync_mem,
629 		.maxlen		= sizeof(sysctl_fib_sync_mem),
630 		.mode		= 0644,
631 		.proc_handler	= proc_douintvec_minmax,
632 		.extra1		= &sysctl_fib_sync_mem_min,
633 		.extra2		= &sysctl_fib_sync_mem_max,
634 	},
635 };
636 
637 static struct ctl_table ipv4_net_table[] = {
638 	{
639 		.procname	= "tcp_max_tw_buckets",
640 		.data		= &init_net.ipv4.tcp_death_row.sysctl_max_tw_buckets,
641 		.maxlen		= sizeof(int),
642 		.mode		= 0644,
643 		.proc_handler	= proc_dointvec
644 	},
645 	{
646 		.procname	= "icmp_echo_ignore_all",
647 		.data		= &init_net.ipv4.sysctl_icmp_echo_ignore_all,
648 		.maxlen		= sizeof(u8),
649 		.mode		= 0644,
650 		.proc_handler	= proc_dou8vec_minmax,
651 		.extra1		= SYSCTL_ZERO,
652 		.extra2		= SYSCTL_ONE
653 	},
654 	{
655 		.procname	= "icmp_echo_enable_probe",
656 		.data		= &init_net.ipv4.sysctl_icmp_echo_enable_probe,
657 		.maxlen		= sizeof(u8),
658 		.mode		= 0644,
659 		.proc_handler	= proc_dou8vec_minmax,
660 		.extra1		= SYSCTL_ZERO,
661 		.extra2		= SYSCTL_ONE
662 	},
663 	{
664 		.procname	= "icmp_echo_ignore_broadcasts",
665 		.data		= &init_net.ipv4.sysctl_icmp_echo_ignore_broadcasts,
666 		.maxlen		= sizeof(u8),
667 		.mode		= 0644,
668 		.proc_handler	= proc_dou8vec_minmax,
669 		.extra1		= SYSCTL_ZERO,
670 		.extra2		= SYSCTL_ONE
671 	},
672 	{
673 		.procname	= "icmp_ignore_bogus_error_responses",
674 		.data		= &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses,
675 		.maxlen		= sizeof(u8),
676 		.mode		= 0644,
677 		.proc_handler	= proc_dou8vec_minmax,
678 		.extra1		= SYSCTL_ZERO,
679 		.extra2		= SYSCTL_ONE
680 	},
681 	{
682 		.procname	= "icmp_errors_use_inbound_ifaddr",
683 		.data		= &init_net.ipv4.sysctl_icmp_errors_use_inbound_ifaddr,
684 		.maxlen		= sizeof(u8),
685 		.mode		= 0644,
686 		.proc_handler	= proc_dou8vec_minmax,
687 		.extra1		= SYSCTL_ZERO,
688 		.extra2		= SYSCTL_ONE
689 	},
690 	{
691 		.procname	= "icmp_ratelimit",
692 		.data		= &init_net.ipv4.sysctl_icmp_ratelimit,
693 		.maxlen		= sizeof(int),
694 		.mode		= 0644,
695 		.proc_handler	= proc_dointvec_ms_jiffies,
696 	},
697 	{
698 		.procname	= "icmp_ratemask",
699 		.data		= &init_net.ipv4.sysctl_icmp_ratemask,
700 		.maxlen		= sizeof(int),
701 		.mode		= 0644,
702 		.proc_handler	= proc_dointvec
703 	},
704 	{
705 		.procname	= "ping_group_range",
706 		.data		= &init_net.ipv4.ping_group_range.range,
707 		.maxlen		= sizeof(gid_t)*2,
708 		.mode		= 0644,
709 		.proc_handler	= ipv4_ping_group_range,
710 	},
711 #ifdef CONFIG_NET_L3_MASTER_DEV
712 	{
713 		.procname	= "raw_l3mdev_accept",
714 		.data		= &init_net.ipv4.sysctl_raw_l3mdev_accept,
715 		.maxlen		= sizeof(u8),
716 		.mode		= 0644,
717 		.proc_handler	= proc_dou8vec_minmax,
718 		.extra1		= SYSCTL_ZERO,
719 		.extra2		= SYSCTL_ONE,
720 	},
721 #endif
722 	{
723 		.procname	= "tcp_ecn",
724 		.data		= &init_net.ipv4.sysctl_tcp_ecn,
725 		.maxlen		= sizeof(u8),
726 		.mode		= 0644,
727 		.proc_handler	= proc_dou8vec_minmax,
728 		.extra1		= SYSCTL_ZERO,
729 		.extra2		= SYSCTL_TWO,
730 	},
731 	{
732 		.procname	= "tcp_ecn_fallback",
733 		.data		= &init_net.ipv4.sysctl_tcp_ecn_fallback,
734 		.maxlen		= sizeof(u8),
735 		.mode		= 0644,
736 		.proc_handler	= proc_dou8vec_minmax,
737 		.extra1		= SYSCTL_ZERO,
738 		.extra2		= SYSCTL_ONE,
739 	},
740 	{
741 		.procname	= "ip_dynaddr",
742 		.data		= &init_net.ipv4.sysctl_ip_dynaddr,
743 		.maxlen		= sizeof(u8),
744 		.mode		= 0644,
745 		.proc_handler	= proc_dou8vec_minmax,
746 	},
747 	{
748 		.procname	= "ip_early_demux",
749 		.data		= &init_net.ipv4.sysctl_ip_early_demux,
750 		.maxlen		= sizeof(u8),
751 		.mode		= 0644,
752 		.proc_handler	= proc_dou8vec_minmax,
753 	},
754 	{
755 		.procname       = "udp_early_demux",
756 		.data           = &init_net.ipv4.sysctl_udp_early_demux,
757 		.maxlen         = sizeof(u8),
758 		.mode           = 0644,
759 		.proc_handler   = proc_dou8vec_minmax,
760 	},
761 	{
762 		.procname       = "tcp_early_demux",
763 		.data           = &init_net.ipv4.sysctl_tcp_early_demux,
764 		.maxlen         = sizeof(u8),
765 		.mode           = 0644,
766 		.proc_handler   = proc_dou8vec_minmax,
767 	},
768 	{
769 		.procname       = "nexthop_compat_mode",
770 		.data           = &init_net.ipv4.sysctl_nexthop_compat_mode,
771 		.maxlen         = sizeof(u8),
772 		.mode           = 0644,
773 		.proc_handler   = proc_dou8vec_minmax,
774 		.extra1		= SYSCTL_ZERO,
775 		.extra2		= SYSCTL_ONE,
776 	},
777 	{
778 		.procname	= "ip_default_ttl",
779 		.data		= &init_net.ipv4.sysctl_ip_default_ttl,
780 		.maxlen		= sizeof(u8),
781 		.mode		= 0644,
782 		.proc_handler	= proc_dou8vec_minmax,
783 		.extra1		= &ip_ttl_min,
784 		.extra2		= &ip_ttl_max,
785 	},
786 	{
787 		.procname	= "ip_local_port_range",
788 		.maxlen		= 0,
789 		.data		= &init_net,
790 		.mode		= 0644,
791 		.proc_handler	= ipv4_local_port_range,
792 	},
793 	{
794 		.procname	= "ip_local_reserved_ports",
795 		.data		= &init_net.ipv4.sysctl_local_reserved_ports,
796 		.maxlen		= 65536,
797 		.mode		= 0644,
798 		.proc_handler	= proc_do_large_bitmap,
799 	},
800 	{
801 		.procname	= "ip_no_pmtu_disc",
802 		.data		= &init_net.ipv4.sysctl_ip_no_pmtu_disc,
803 		.maxlen		= sizeof(u8),
804 		.mode		= 0644,
805 		.proc_handler	= proc_dou8vec_minmax,
806 	},
807 	{
808 		.procname	= "ip_forward_use_pmtu",
809 		.data		= &init_net.ipv4.sysctl_ip_fwd_use_pmtu,
810 		.maxlen		= sizeof(u8),
811 		.mode		= 0644,
812 		.proc_handler	= proc_dou8vec_minmax,
813 	},
814 	{
815 		.procname	= "ip_forward_update_priority",
816 		.data		= &init_net.ipv4.sysctl_ip_fwd_update_priority,
817 		.maxlen		= sizeof(u8),
818 		.mode		= 0644,
819 		.proc_handler   = ipv4_fwd_update_priority,
820 		.extra1		= SYSCTL_ZERO,
821 		.extra2		= SYSCTL_ONE,
822 	},
823 	{
824 		.procname	= "ip_nonlocal_bind",
825 		.data		= &init_net.ipv4.sysctl_ip_nonlocal_bind,
826 		.maxlen		= sizeof(u8),
827 		.mode		= 0644,
828 		.proc_handler	= proc_dou8vec_minmax,
829 	},
830 	{
831 		.procname	= "ip_autobind_reuse",
832 		.data		= &init_net.ipv4.sysctl_ip_autobind_reuse,
833 		.maxlen		= sizeof(u8),
834 		.mode		= 0644,
835 		.proc_handler	= proc_dou8vec_minmax,
836 		.extra1         = SYSCTL_ZERO,
837 		.extra2         = SYSCTL_ONE,
838 	},
839 	{
840 		.procname	= "fwmark_reflect",
841 		.data		= &init_net.ipv4.sysctl_fwmark_reflect,
842 		.maxlen		= sizeof(u8),
843 		.mode		= 0644,
844 		.proc_handler	= proc_dou8vec_minmax,
845 	},
846 	{
847 		.procname	= "tcp_fwmark_accept",
848 		.data		= &init_net.ipv4.sysctl_tcp_fwmark_accept,
849 		.maxlen		= sizeof(u8),
850 		.mode		= 0644,
851 		.proc_handler	= proc_dou8vec_minmax,
852 	},
853 #ifdef CONFIG_NET_L3_MASTER_DEV
854 	{
855 		.procname	= "tcp_l3mdev_accept",
856 		.data		= &init_net.ipv4.sysctl_tcp_l3mdev_accept,
857 		.maxlen		= sizeof(u8),
858 		.mode		= 0644,
859 		.proc_handler	= proc_dou8vec_minmax,
860 		.extra1		= SYSCTL_ZERO,
861 		.extra2		= SYSCTL_ONE,
862 	},
863 #endif
864 	{
865 		.procname	= "tcp_mtu_probing",
866 		.data		= &init_net.ipv4.sysctl_tcp_mtu_probing,
867 		.maxlen		= sizeof(u8),
868 		.mode		= 0644,
869 		.proc_handler	= proc_dou8vec_minmax,
870 	},
871 	{
872 		.procname	= "tcp_base_mss",
873 		.data		= &init_net.ipv4.sysctl_tcp_base_mss,
874 		.maxlen		= sizeof(int),
875 		.mode		= 0644,
876 		.proc_handler	= proc_dointvec,
877 	},
878 	{
879 		.procname	= "tcp_min_snd_mss",
880 		.data		= &init_net.ipv4.sysctl_tcp_min_snd_mss,
881 		.maxlen		= sizeof(int),
882 		.mode		= 0644,
883 		.proc_handler	= proc_dointvec_minmax,
884 		.extra1		= &tcp_min_snd_mss_min,
885 		.extra2		= &tcp_min_snd_mss_max,
886 	},
887 	{
888 		.procname	= "tcp_mtu_probe_floor",
889 		.data		= &init_net.ipv4.sysctl_tcp_mtu_probe_floor,
890 		.maxlen		= sizeof(int),
891 		.mode		= 0644,
892 		.proc_handler	= proc_dointvec_minmax,
893 		.extra1		= &tcp_min_snd_mss_min,
894 		.extra2		= &tcp_min_snd_mss_max,
895 	},
896 	{
897 		.procname	= "tcp_probe_threshold",
898 		.data		= &init_net.ipv4.sysctl_tcp_probe_threshold,
899 		.maxlen		= sizeof(int),
900 		.mode		= 0644,
901 		.proc_handler	= proc_dointvec,
902 	},
903 	{
904 		.procname	= "tcp_probe_interval",
905 		.data		= &init_net.ipv4.sysctl_tcp_probe_interval,
906 		.maxlen		= sizeof(u32),
907 		.mode		= 0644,
908 		.proc_handler	= proc_douintvec_minmax,
909 		.extra2		= &u32_max_div_HZ,
910 	},
911 	{
912 		.procname	= "igmp_link_local_mcast_reports",
913 		.data		= &init_net.ipv4.sysctl_igmp_llm_reports,
914 		.maxlen		= sizeof(u8),
915 		.mode		= 0644,
916 		.proc_handler	= proc_dou8vec_minmax,
917 	},
918 	{
919 		.procname	= "igmp_max_memberships",
920 		.data		= &init_net.ipv4.sysctl_igmp_max_memberships,
921 		.maxlen		= sizeof(int),
922 		.mode		= 0644,
923 		.proc_handler	= proc_dointvec
924 	},
925 	{
926 		.procname	= "igmp_max_msf",
927 		.data		= &init_net.ipv4.sysctl_igmp_max_msf,
928 		.maxlen		= sizeof(int),
929 		.mode		= 0644,
930 		.proc_handler	= proc_dointvec
931 	},
932 #ifdef CONFIG_IP_MULTICAST
933 	{
934 		.procname	= "igmp_qrv",
935 		.data		= &init_net.ipv4.sysctl_igmp_qrv,
936 		.maxlen		= sizeof(int),
937 		.mode		= 0644,
938 		.proc_handler	= proc_dointvec_minmax,
939 		.extra1		= SYSCTL_ONE
940 	},
941 #endif
942 	{
943 		.procname	= "tcp_congestion_control",
944 		.data		= &init_net.ipv4.tcp_congestion_control,
945 		.mode		= 0644,
946 		.maxlen		= TCP_CA_NAME_MAX,
947 		.proc_handler	= proc_tcp_congestion_control,
948 	},
949 	{
950 		.procname	= "tcp_available_congestion_control",
951 		.maxlen		= TCP_CA_BUF_MAX,
952 		.mode		= 0444,
953 		.proc_handler   = proc_tcp_available_congestion_control,
954 	},
955 	{
956 		.procname	= "tcp_allowed_congestion_control",
957 		.maxlen		= TCP_CA_BUF_MAX,
958 		.mode		= 0644,
959 		.proc_handler   = proc_allowed_congestion_control,
960 	},
961 	{
962 		.procname	= "tcp_keepalive_time",
963 		.data		= &init_net.ipv4.sysctl_tcp_keepalive_time,
964 		.maxlen		= sizeof(int),
965 		.mode		= 0644,
966 		.proc_handler	= proc_dointvec_jiffies,
967 	},
968 	{
969 		.procname	= "tcp_keepalive_probes",
970 		.data		= &init_net.ipv4.sysctl_tcp_keepalive_probes,
971 		.maxlen		= sizeof(u8),
972 		.mode		= 0644,
973 		.proc_handler	= proc_dou8vec_minmax,
974 	},
975 	{
976 		.procname	= "tcp_keepalive_intvl",
977 		.data		= &init_net.ipv4.sysctl_tcp_keepalive_intvl,
978 		.maxlen		= sizeof(int),
979 		.mode		= 0644,
980 		.proc_handler	= proc_dointvec_jiffies,
981 	},
982 	{
983 		.procname	= "tcp_syn_retries",
984 		.data		= &init_net.ipv4.sysctl_tcp_syn_retries,
985 		.maxlen		= sizeof(u8),
986 		.mode		= 0644,
987 		.proc_handler	= proc_dou8vec_minmax,
988 		.extra1		= &tcp_syn_retries_min,
989 		.extra2		= &tcp_syn_retries_max
990 	},
991 	{
992 		.procname	= "tcp_synack_retries",
993 		.data		= &init_net.ipv4.sysctl_tcp_synack_retries,
994 		.maxlen		= sizeof(u8),
995 		.mode		= 0644,
996 		.proc_handler	= proc_dou8vec_minmax,
997 	},
998 #ifdef CONFIG_SYN_COOKIES
999 	{
1000 		.procname	= "tcp_syncookies",
1001 		.data		= &init_net.ipv4.sysctl_tcp_syncookies,
1002 		.maxlen		= sizeof(u8),
1003 		.mode		= 0644,
1004 		.proc_handler	= proc_dou8vec_minmax,
1005 	},
1006 #endif
1007 	{
1008 		.procname	= "tcp_migrate_req",
1009 		.data		= &init_net.ipv4.sysctl_tcp_migrate_req,
1010 		.maxlen		= sizeof(u8),
1011 		.mode		= 0644,
1012 		.proc_handler	= proc_dou8vec_minmax,
1013 		.extra1		= SYSCTL_ZERO,
1014 		.extra2		= SYSCTL_ONE
1015 	},
1016 	{
1017 		.procname	= "tcp_reordering",
1018 		.data		= &init_net.ipv4.sysctl_tcp_reordering,
1019 		.maxlen		= sizeof(int),
1020 		.mode		= 0644,
1021 		.proc_handler	= proc_dointvec
1022 	},
1023 	{
1024 		.procname	= "tcp_retries1",
1025 		.data		= &init_net.ipv4.sysctl_tcp_retries1,
1026 		.maxlen		= sizeof(u8),
1027 		.mode		= 0644,
1028 		.proc_handler	= proc_dou8vec_minmax,
1029 		.extra2		= &tcp_retr1_max
1030 	},
1031 	{
1032 		.procname	= "tcp_retries2",
1033 		.data		= &init_net.ipv4.sysctl_tcp_retries2,
1034 		.maxlen		= sizeof(u8),
1035 		.mode		= 0644,
1036 		.proc_handler	= proc_dou8vec_minmax,
1037 	},
1038 	{
1039 		.procname	= "tcp_orphan_retries",
1040 		.data		= &init_net.ipv4.sysctl_tcp_orphan_retries,
1041 		.maxlen		= sizeof(u8),
1042 		.mode		= 0644,
1043 		.proc_handler	= proc_dou8vec_minmax,
1044 	},
1045 	{
1046 		.procname	= "tcp_fin_timeout",
1047 		.data		= &init_net.ipv4.sysctl_tcp_fin_timeout,
1048 		.maxlen		= sizeof(int),
1049 		.mode		= 0644,
1050 		.proc_handler	= proc_dointvec_jiffies,
1051 	},
1052 	{
1053 		.procname	= "tcp_notsent_lowat",
1054 		.data		= &init_net.ipv4.sysctl_tcp_notsent_lowat,
1055 		.maxlen		= sizeof(unsigned int),
1056 		.mode		= 0644,
1057 		.proc_handler	= proc_douintvec,
1058 	},
1059 	{
1060 		.procname	= "tcp_tw_reuse",
1061 		.data		= &init_net.ipv4.sysctl_tcp_tw_reuse,
1062 		.maxlen		= sizeof(u8),
1063 		.mode		= 0644,
1064 		.proc_handler	= proc_dou8vec_minmax,
1065 		.extra1		= SYSCTL_ZERO,
1066 		.extra2		= SYSCTL_TWO,
1067 	},
1068 	{
1069 		.procname	= "tcp_max_syn_backlog",
1070 		.data		= &init_net.ipv4.sysctl_max_syn_backlog,
1071 		.maxlen		= sizeof(int),
1072 		.mode		= 0644,
1073 		.proc_handler	= proc_dointvec
1074 	},
1075 	{
1076 		.procname	= "tcp_fastopen",
1077 		.data		= &init_net.ipv4.sysctl_tcp_fastopen,
1078 		.maxlen		= sizeof(int),
1079 		.mode		= 0644,
1080 		.proc_handler	= proc_dointvec,
1081 	},
1082 	{
1083 		.procname	= "tcp_fastopen_key",
1084 		.mode		= 0600,
1085 		.data		= &init_net.ipv4.sysctl_tcp_fastopen,
1086 		/* maxlen to print the list of keys in hex (*2), with dashes
1087 		 * separating doublewords and a comma in between keys.
1088 		 */
1089 		.maxlen		= ((TCP_FASTOPEN_KEY_LENGTH *
1090 				   2 * TCP_FASTOPEN_KEY_MAX) +
1091 				   (TCP_FASTOPEN_KEY_MAX * 5)),
1092 		.proc_handler	= proc_tcp_fastopen_key,
1093 	},
1094 	{
1095 		.procname	= "tcp_fastopen_blackhole_timeout_sec",
1096 		.data		= &init_net.ipv4.sysctl_tcp_fastopen_blackhole_timeout,
1097 		.maxlen		= sizeof(int),
1098 		.mode		= 0644,
1099 		.proc_handler	= proc_tfo_blackhole_detect_timeout,
1100 		.extra1		= SYSCTL_ZERO,
1101 	},
1102 #ifdef CONFIG_IP_ROUTE_MULTIPATH
1103 	{
1104 		.procname	= "fib_multipath_use_neigh",
1105 		.data		= &init_net.ipv4.sysctl_fib_multipath_use_neigh,
1106 		.maxlen		= sizeof(u8),
1107 		.mode		= 0644,
1108 		.proc_handler	= proc_dou8vec_minmax,
1109 		.extra1		= SYSCTL_ZERO,
1110 		.extra2		= SYSCTL_ONE,
1111 	},
1112 	{
1113 		.procname	= "fib_multipath_hash_policy",
1114 		.data		= &init_net.ipv4.sysctl_fib_multipath_hash_policy,
1115 		.maxlen		= sizeof(u8),
1116 		.mode		= 0644,
1117 		.proc_handler	= proc_fib_multipath_hash_policy,
1118 		.extra1		= SYSCTL_ZERO,
1119 		.extra2		= SYSCTL_THREE,
1120 	},
1121 	{
1122 		.procname	= "fib_multipath_hash_fields",
1123 		.data		= &init_net.ipv4.sysctl_fib_multipath_hash_fields,
1124 		.maxlen		= sizeof(u32),
1125 		.mode		= 0644,
1126 		.proc_handler	= proc_fib_multipath_hash_fields,
1127 		.extra1		= SYSCTL_ONE,
1128 		.extra2		= &fib_multipath_hash_fields_all_mask,
1129 	},
1130 	{
1131 		.procname	= "fib_multipath_hash_seed",
1132 		.data		= &init_net,
1133 		.maxlen		= sizeof(u32),
1134 		.mode		= 0644,
1135 		.proc_handler	= proc_fib_multipath_hash_seed,
1136 	},
1137 #endif
1138 	{
1139 		.procname	= "ip_unprivileged_port_start",
1140 		.maxlen		= sizeof(int),
1141 		.data		= &init_net.ipv4.sysctl_ip_prot_sock,
1142 		.mode		= 0644,
1143 		.proc_handler	= ipv4_privileged_ports,
1144 	},
1145 #ifdef CONFIG_NET_L3_MASTER_DEV
1146 	{
1147 		.procname	= "udp_l3mdev_accept",
1148 		.data		= &init_net.ipv4.sysctl_udp_l3mdev_accept,
1149 		.maxlen		= sizeof(u8),
1150 		.mode		= 0644,
1151 		.proc_handler	= proc_dou8vec_minmax,
1152 		.extra1		= SYSCTL_ZERO,
1153 		.extra2		= SYSCTL_ONE,
1154 	},
1155 #endif
1156 	{
1157 		.procname	= "tcp_sack",
1158 		.data		= &init_net.ipv4.sysctl_tcp_sack,
1159 		.maxlen		= sizeof(u8),
1160 		.mode		= 0644,
1161 		.proc_handler	= proc_dou8vec_minmax,
1162 	},
1163 	{
1164 		.procname	= "tcp_window_scaling",
1165 		.data		= &init_net.ipv4.sysctl_tcp_window_scaling,
1166 		.maxlen		= sizeof(u8),
1167 		.mode		= 0644,
1168 		.proc_handler	= proc_dou8vec_minmax,
1169 	},
1170 	{
1171 		.procname	= "tcp_timestamps",
1172 		.data		= &init_net.ipv4.sysctl_tcp_timestamps,
1173 		.maxlen		= sizeof(u8),
1174 		.mode		= 0644,
1175 		.proc_handler	= proc_dou8vec_minmax,
1176 	},
1177 	{
1178 		.procname	= "tcp_early_retrans",
1179 		.data		= &init_net.ipv4.sysctl_tcp_early_retrans,
1180 		.maxlen		= sizeof(u8),
1181 		.mode		= 0644,
1182 		.proc_handler	= proc_dou8vec_minmax,
1183 		.extra1		= SYSCTL_ZERO,
1184 		.extra2		= SYSCTL_FOUR,
1185 	},
1186 	{
1187 		.procname	= "tcp_recovery",
1188 		.data		= &init_net.ipv4.sysctl_tcp_recovery,
1189 		.maxlen		= sizeof(u8),
1190 		.mode		= 0644,
1191 		.proc_handler	= proc_dou8vec_minmax,
1192 	},
1193 	{
1194 		.procname       = "tcp_thin_linear_timeouts",
1195 		.data           = &init_net.ipv4.sysctl_tcp_thin_linear_timeouts,
1196 		.maxlen         = sizeof(u8),
1197 		.mode           = 0644,
1198 		.proc_handler   = proc_dou8vec_minmax,
1199 	},
1200 	{
1201 		.procname	= "tcp_slow_start_after_idle",
1202 		.data		= &init_net.ipv4.sysctl_tcp_slow_start_after_idle,
1203 		.maxlen		= sizeof(u8),
1204 		.mode		= 0644,
1205 		.proc_handler	= proc_dou8vec_minmax,
1206 	},
1207 	{
1208 		.procname	= "tcp_retrans_collapse",
1209 		.data		= &init_net.ipv4.sysctl_tcp_retrans_collapse,
1210 		.maxlen		= sizeof(u8),
1211 		.mode		= 0644,
1212 		.proc_handler	= proc_dou8vec_minmax,
1213 	},
1214 	{
1215 		.procname	= "tcp_stdurg",
1216 		.data		= &init_net.ipv4.sysctl_tcp_stdurg,
1217 		.maxlen		= sizeof(u8),
1218 		.mode		= 0644,
1219 		.proc_handler	= proc_dou8vec_minmax,
1220 	},
1221 	{
1222 		.procname	= "tcp_rfc1337",
1223 		.data		= &init_net.ipv4.sysctl_tcp_rfc1337,
1224 		.maxlen		= sizeof(u8),
1225 		.mode		= 0644,
1226 		.proc_handler	= proc_dou8vec_minmax,
1227 	},
1228 	{
1229 		.procname	= "tcp_abort_on_overflow",
1230 		.data		= &init_net.ipv4.sysctl_tcp_abort_on_overflow,
1231 		.maxlen		= sizeof(u8),
1232 		.mode		= 0644,
1233 		.proc_handler	= proc_dou8vec_minmax,
1234 	},
1235 	{
1236 		.procname	= "tcp_fack",
1237 		.data		= &init_net.ipv4.sysctl_tcp_fack,
1238 		.maxlen		= sizeof(u8),
1239 		.mode		= 0644,
1240 		.proc_handler	= proc_dou8vec_minmax,
1241 	},
1242 	{
1243 		.procname	= "tcp_max_reordering",
1244 		.data		= &init_net.ipv4.sysctl_tcp_max_reordering,
1245 		.maxlen		= sizeof(int),
1246 		.mode		= 0644,
1247 		.proc_handler	= proc_dointvec
1248 	},
1249 	{
1250 		.procname	= "tcp_dsack",
1251 		.data		= &init_net.ipv4.sysctl_tcp_dsack,
1252 		.maxlen		= sizeof(u8),
1253 		.mode		= 0644,
1254 		.proc_handler	= proc_dou8vec_minmax,
1255 	},
1256 	{
1257 		.procname	= "tcp_app_win",
1258 		.data		= &init_net.ipv4.sysctl_tcp_app_win,
1259 		.maxlen		= sizeof(u8),
1260 		.mode		= 0644,
1261 		.proc_handler	= proc_dou8vec_minmax,
1262 		.extra1		= SYSCTL_ZERO,
1263 		.extra2		= &tcp_app_win_max,
1264 	},
1265 	{
1266 		.procname	= "tcp_adv_win_scale",
1267 		.data		= &init_net.ipv4.sysctl_tcp_adv_win_scale,
1268 		.maxlen		= sizeof(int),
1269 		.mode		= 0644,
1270 		.proc_handler	= proc_dointvec_minmax,
1271 		.extra1		= &tcp_adv_win_scale_min,
1272 		.extra2		= &tcp_adv_win_scale_max,
1273 	},
1274 	{
1275 		.procname	= "tcp_frto",
1276 		.data		= &init_net.ipv4.sysctl_tcp_frto,
1277 		.maxlen		= sizeof(u8),
1278 		.mode		= 0644,
1279 		.proc_handler	= proc_dou8vec_minmax,
1280 	},
1281 	{
1282 		.procname	= "tcp_no_metrics_save",
1283 		.data		= &init_net.ipv4.sysctl_tcp_nometrics_save,
1284 		.maxlen		= sizeof(u8),
1285 		.mode		= 0644,
1286 		.proc_handler	= proc_dou8vec_minmax,
1287 	},
1288 	{
1289 		.procname	= "tcp_no_ssthresh_metrics_save",
1290 		.data		= &init_net.ipv4.sysctl_tcp_no_ssthresh_metrics_save,
1291 		.maxlen		= sizeof(u8),
1292 		.mode		= 0644,
1293 		.proc_handler	= proc_dou8vec_minmax,
1294 		.extra1		= SYSCTL_ZERO,
1295 		.extra2		= SYSCTL_ONE,
1296 	},
1297 	{
1298 		.procname	= "tcp_moderate_rcvbuf",
1299 		.data		= &init_net.ipv4.sysctl_tcp_moderate_rcvbuf,
1300 		.maxlen		= sizeof(u8),
1301 		.mode		= 0644,
1302 		.proc_handler	= proc_dou8vec_minmax,
1303 	},
1304 	{
1305 		.procname	= "tcp_tso_win_divisor",
1306 		.data		= &init_net.ipv4.sysctl_tcp_tso_win_divisor,
1307 		.maxlen		= sizeof(u8),
1308 		.mode		= 0644,
1309 		.proc_handler	= proc_dou8vec_minmax,
1310 	},
1311 	{
1312 		.procname	= "tcp_workaround_signed_windows",
1313 		.data		= &init_net.ipv4.sysctl_tcp_workaround_signed_windows,
1314 		.maxlen		= sizeof(u8),
1315 		.mode		= 0644,
1316 		.proc_handler	= proc_dou8vec_minmax,
1317 	},
1318 	{
1319 		.procname	= "tcp_limit_output_bytes",
1320 		.data		= &init_net.ipv4.sysctl_tcp_limit_output_bytes,
1321 		.maxlen		= sizeof(int),
1322 		.mode		= 0644,
1323 		.proc_handler	= proc_dointvec
1324 	},
1325 	{
1326 		.procname	= "tcp_challenge_ack_limit",
1327 		.data		= &init_net.ipv4.sysctl_tcp_challenge_ack_limit,
1328 		.maxlen		= sizeof(int),
1329 		.mode		= 0644,
1330 		.proc_handler	= proc_dointvec
1331 	},
1332 	{
1333 		.procname	= "tcp_min_tso_segs",
1334 		.data		= &init_net.ipv4.sysctl_tcp_min_tso_segs,
1335 		.maxlen		= sizeof(u8),
1336 		.mode		= 0644,
1337 		.proc_handler	= proc_dou8vec_minmax,
1338 		.extra1		= SYSCTL_ONE,
1339 	},
1340 	{
1341 		.procname	= "tcp_tso_rtt_log",
1342 		.data		= &init_net.ipv4.sysctl_tcp_tso_rtt_log,
1343 		.maxlen		= sizeof(u8),
1344 		.mode		= 0644,
1345 		.proc_handler	= proc_dou8vec_minmax,
1346 	},
1347 	{
1348 		.procname	= "tcp_min_rtt_wlen",
1349 		.data		= &init_net.ipv4.sysctl_tcp_min_rtt_wlen,
1350 		.maxlen		= sizeof(int),
1351 		.mode		= 0644,
1352 		.proc_handler	= proc_dointvec_minmax,
1353 		.extra1		= SYSCTL_ZERO,
1354 		.extra2		= &one_day_secs
1355 	},
1356 	{
1357 		.procname	= "tcp_autocorking",
1358 		.data		= &init_net.ipv4.sysctl_tcp_autocorking,
1359 		.maxlen		= sizeof(u8),
1360 		.mode		= 0644,
1361 		.proc_handler	= proc_dou8vec_minmax,
1362 		.extra1		= SYSCTL_ZERO,
1363 		.extra2		= SYSCTL_ONE,
1364 	},
1365 	{
1366 		.procname	= "tcp_invalid_ratelimit",
1367 		.data		= &init_net.ipv4.sysctl_tcp_invalid_ratelimit,
1368 		.maxlen		= sizeof(int),
1369 		.mode		= 0644,
1370 		.proc_handler	= proc_dointvec_ms_jiffies,
1371 	},
1372 	{
1373 		.procname	= "tcp_pacing_ss_ratio",
1374 		.data		= &init_net.ipv4.sysctl_tcp_pacing_ss_ratio,
1375 		.maxlen		= sizeof(int),
1376 		.mode		= 0644,
1377 		.proc_handler	= proc_dointvec_minmax,
1378 		.extra1		= SYSCTL_ZERO,
1379 		.extra2		= SYSCTL_ONE_THOUSAND,
1380 	},
1381 	{
1382 		.procname	= "tcp_pacing_ca_ratio",
1383 		.data		= &init_net.ipv4.sysctl_tcp_pacing_ca_ratio,
1384 		.maxlen		= sizeof(int),
1385 		.mode		= 0644,
1386 		.proc_handler	= proc_dointvec_minmax,
1387 		.extra1		= SYSCTL_ZERO,
1388 		.extra2		= SYSCTL_ONE_THOUSAND,
1389 	},
1390 	{
1391 		.procname	= "tcp_wmem",
1392 		.data		= &init_net.ipv4.sysctl_tcp_wmem,
1393 		.maxlen		= sizeof(init_net.ipv4.sysctl_tcp_wmem),
1394 		.mode		= 0644,
1395 		.proc_handler	= proc_dointvec_minmax,
1396 		.extra1		= SYSCTL_ONE,
1397 	},
1398 	{
1399 		.procname	= "tcp_rmem",
1400 		.data		= &init_net.ipv4.sysctl_tcp_rmem,
1401 		.maxlen		= sizeof(init_net.ipv4.sysctl_tcp_rmem),
1402 		.mode		= 0644,
1403 		.proc_handler	= proc_dointvec_minmax,
1404 		.extra1		= SYSCTL_ONE,
1405 	},
1406 	{
1407 		.procname	= "tcp_comp_sack_delay_ns",
1408 		.data		= &init_net.ipv4.sysctl_tcp_comp_sack_delay_ns,
1409 		.maxlen		= sizeof(unsigned long),
1410 		.mode		= 0644,
1411 		.proc_handler	= proc_doulongvec_minmax,
1412 	},
1413 	{
1414 		.procname	= "tcp_comp_sack_slack_ns",
1415 		.data		= &init_net.ipv4.sysctl_tcp_comp_sack_slack_ns,
1416 		.maxlen		= sizeof(unsigned long),
1417 		.mode		= 0644,
1418 		.proc_handler	= proc_doulongvec_minmax,
1419 	},
1420 	{
1421 		.procname	= "tcp_comp_sack_nr",
1422 		.data		= &init_net.ipv4.sysctl_tcp_comp_sack_nr,
1423 		.maxlen		= sizeof(u8),
1424 		.mode		= 0644,
1425 		.proc_handler	= proc_dou8vec_minmax,
1426 		.extra1		= SYSCTL_ZERO,
1427 	},
1428 	{
1429 		.procname	= "tcp_backlog_ack_defer",
1430 		.data		= &init_net.ipv4.sysctl_tcp_backlog_ack_defer,
1431 		.maxlen		= sizeof(u8),
1432 		.mode		= 0644,
1433 		.proc_handler	= proc_dou8vec_minmax,
1434 		.extra1		= SYSCTL_ZERO,
1435 		.extra2		= SYSCTL_ONE,
1436 	},
1437 	{
1438 		.procname       = "tcp_reflect_tos",
1439 		.data           = &init_net.ipv4.sysctl_tcp_reflect_tos,
1440 		.maxlen         = sizeof(u8),
1441 		.mode           = 0644,
1442 		.proc_handler   = proc_dou8vec_minmax,
1443 		.extra1         = SYSCTL_ZERO,
1444 		.extra2         = SYSCTL_ONE,
1445 	},
1446 	{
1447 		.procname	= "tcp_ehash_entries",
1448 		.data		= &init_net.ipv4.sysctl_tcp_child_ehash_entries,
1449 		.mode		= 0444,
1450 		.proc_handler	= proc_tcp_ehash_entries,
1451 	},
1452 	{
1453 		.procname	= "tcp_child_ehash_entries",
1454 		.data		= &init_net.ipv4.sysctl_tcp_child_ehash_entries,
1455 		.maxlen		= sizeof(unsigned int),
1456 		.mode		= 0644,
1457 		.proc_handler	= proc_douintvec_minmax,
1458 		.extra1		= SYSCTL_ZERO,
1459 		.extra2		= &tcp_child_ehash_entries_max,
1460 	},
1461 	{
1462 		.procname	= "udp_hash_entries",
1463 		.data		= &init_net.ipv4.sysctl_udp_child_hash_entries,
1464 		.mode		= 0444,
1465 		.proc_handler	= proc_udp_hash_entries,
1466 	},
1467 	{
1468 		.procname	= "udp_child_hash_entries",
1469 		.data		= &init_net.ipv4.sysctl_udp_child_hash_entries,
1470 		.maxlen		= sizeof(unsigned int),
1471 		.mode		= 0644,
1472 		.proc_handler	= proc_douintvec_minmax,
1473 		.extra1		= SYSCTL_ZERO,
1474 		.extra2		= &udp_child_hash_entries_max,
1475 	},
1476 	{
1477 		.procname	= "udp_rmem_min",
1478 		.data		= &init_net.ipv4.sysctl_udp_rmem_min,
1479 		.maxlen		= sizeof(init_net.ipv4.sysctl_udp_rmem_min),
1480 		.mode		= 0644,
1481 		.proc_handler	= proc_dointvec_minmax,
1482 		.extra1		= SYSCTL_ONE
1483 	},
1484 	{
1485 		.procname	= "udp_wmem_min",
1486 		.data		= &init_net.ipv4.sysctl_udp_wmem_min,
1487 		.maxlen		= sizeof(init_net.ipv4.sysctl_udp_wmem_min),
1488 		.mode		= 0644,
1489 		.proc_handler	= proc_dointvec_minmax,
1490 		.extra1		= SYSCTL_ONE
1491 	},
1492 	{
1493 		.procname	= "fib_notify_on_flag_change",
1494 		.data		= &init_net.ipv4.sysctl_fib_notify_on_flag_change,
1495 		.maxlen		= sizeof(u8),
1496 		.mode		= 0644,
1497 		.proc_handler	= proc_dou8vec_minmax,
1498 		.extra1		= SYSCTL_ZERO,
1499 		.extra2		= SYSCTL_TWO,
1500 	},
1501 	{
1502 		.procname       = "tcp_plb_enabled",
1503 		.data           = &init_net.ipv4.sysctl_tcp_plb_enabled,
1504 		.maxlen         = sizeof(u8),
1505 		.mode           = 0644,
1506 		.proc_handler   = proc_dou8vec_minmax,
1507 		.extra1         = SYSCTL_ZERO,
1508 		.extra2         = SYSCTL_ONE,
1509 	},
1510 	{
1511 		.procname       = "tcp_plb_idle_rehash_rounds",
1512 		.data           = &init_net.ipv4.sysctl_tcp_plb_idle_rehash_rounds,
1513 		.maxlen         = sizeof(u8),
1514 		.mode           = 0644,
1515 		.proc_handler   = proc_dou8vec_minmax,
1516 		.extra2		= &tcp_plb_max_rounds,
1517 	},
1518 	{
1519 		.procname       = "tcp_plb_rehash_rounds",
1520 		.data           = &init_net.ipv4.sysctl_tcp_plb_rehash_rounds,
1521 		.maxlen         = sizeof(u8),
1522 		.mode           = 0644,
1523 		.proc_handler   = proc_dou8vec_minmax,
1524 		.extra2         = &tcp_plb_max_rounds,
1525 	},
1526 	{
1527 		.procname       = "tcp_plb_suspend_rto_sec",
1528 		.data           = &init_net.ipv4.sysctl_tcp_plb_suspend_rto_sec,
1529 		.maxlen         = sizeof(u8),
1530 		.mode           = 0644,
1531 		.proc_handler   = proc_dou8vec_minmax,
1532 	},
1533 	{
1534 		.procname       = "tcp_plb_cong_thresh",
1535 		.data           = &init_net.ipv4.sysctl_tcp_plb_cong_thresh,
1536 		.maxlen         = sizeof(int),
1537 		.mode           = 0644,
1538 		.proc_handler   = proc_dointvec_minmax,
1539 		.extra1         = SYSCTL_ZERO,
1540 		.extra2         = &tcp_plb_max_cong_thresh,
1541 	},
1542 	{
1543 		.procname	= "tcp_syn_linear_timeouts",
1544 		.data		= &init_net.ipv4.sysctl_tcp_syn_linear_timeouts,
1545 		.maxlen		= sizeof(u8),
1546 		.mode		= 0644,
1547 		.proc_handler	= proc_dou8vec_minmax,
1548 		.extra1		= SYSCTL_ZERO,
1549 		.extra2		= &tcp_syn_linear_timeouts_max,
1550 	},
1551 	{
1552 		.procname	= "tcp_shrink_window",
1553 		.data		= &init_net.ipv4.sysctl_tcp_shrink_window,
1554 		.maxlen		= sizeof(u8),
1555 		.mode		= 0644,
1556 		.proc_handler	= proc_dou8vec_minmax,
1557 		.extra1		= SYSCTL_ZERO,
1558 		.extra2		= SYSCTL_ONE,
1559 	},
1560 	{
1561 		.procname	= "tcp_pingpong_thresh",
1562 		.data		= &init_net.ipv4.sysctl_tcp_pingpong_thresh,
1563 		.maxlen		= sizeof(u8),
1564 		.mode		= 0644,
1565 		.proc_handler	= proc_dou8vec_minmax,
1566 		.extra1		= SYSCTL_ONE,
1567 	},
1568 	{
1569 		.procname	= "tcp_rto_min_us",
1570 		.data		= &init_net.ipv4.sysctl_tcp_rto_min_us,
1571 		.maxlen		= sizeof(int),
1572 		.mode		= 0644,
1573 		.proc_handler	= proc_dointvec_minmax,
1574 		.extra1		= SYSCTL_ONE,
1575 	},
1576 };
1577 
1578 static __net_init int ipv4_sysctl_init_net(struct net *net)
1579 {
1580 	size_t table_size = ARRAY_SIZE(ipv4_net_table);
1581 	struct ctl_table *table;
1582 
1583 	table = ipv4_net_table;
1584 	if (!net_eq(net, &init_net)) {
1585 		int i;
1586 
1587 		table = kmemdup(table, sizeof(ipv4_net_table), GFP_KERNEL);
1588 		if (!table)
1589 			goto err_alloc;
1590 
1591 		for (i = 0; i < table_size; i++) {
1592 			if (table[i].data) {
1593 				/* Update the variables to point into
1594 				 * the current struct net
1595 				 */
1596 				table[i].data += (void *)net - (void *)&init_net;
1597 			} else {
1598 				/* Entries without data pointer are global;
1599 				 * Make them read-only in non-init_net ns
1600 				 */
1601 				table[i].mode &= ~0222;
1602 			}
1603 		}
1604 	}
1605 
1606 	net->ipv4.ipv4_hdr = register_net_sysctl_sz(net, "net/ipv4", table,
1607 						    table_size);
1608 	if (!net->ipv4.ipv4_hdr)
1609 		goto err_reg;
1610 
1611 	net->ipv4.sysctl_local_reserved_ports = kzalloc(65536 / 8, GFP_KERNEL);
1612 	if (!net->ipv4.sysctl_local_reserved_ports)
1613 		goto err_ports;
1614 
1615 	proc_fib_multipath_hash_set_seed(net, 0);
1616 
1617 	return 0;
1618 
1619 err_ports:
1620 	unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
1621 err_reg:
1622 	if (!net_eq(net, &init_net))
1623 		kfree(table);
1624 err_alloc:
1625 	return -ENOMEM;
1626 }
1627 
1628 static __net_exit void ipv4_sysctl_exit_net(struct net *net)
1629 {
1630 	const struct ctl_table *table;
1631 
1632 	kfree(net->ipv4.sysctl_local_reserved_ports);
1633 	table = net->ipv4.ipv4_hdr->ctl_table_arg;
1634 	unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
1635 	kfree(table);
1636 }
1637 
1638 static __net_initdata struct pernet_operations ipv4_sysctl_ops = {
1639 	.init = ipv4_sysctl_init_net,
1640 	.exit = ipv4_sysctl_exit_net,
1641 };
1642 
1643 static __init int sysctl_ipv4_init(void)
1644 {
1645 	struct ctl_table_header *hdr;
1646 
1647 	hdr = register_net_sysctl(&init_net, "net/ipv4", ipv4_table);
1648 	if (!hdr)
1649 		return -ENOMEM;
1650 
1651 	proc_fib_multipath_hash_init_rand_seed();
1652 
1653 	if (register_pernet_subsys(&ipv4_sysctl_ops)) {
1654 		unregister_net_sysctl_table(hdr);
1655 		return -ENOMEM;
1656 	}
1657 
1658 	return 0;
1659 }
1660 
1661 __initcall(sysctl_ipv4_init);
1662