Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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
31static int zero;
32static int one = 1;
33static int two = 2;
34static int four = 4;
35static int thousand = 1000;
36static int gso_max_segs = GSO_MAX_SEGS;
37static int tcp_retr1_max = 255;
38static int ip_local_port_range_min[] = { 1, 1 };
39static int ip_local_port_range_max[] = { 65535, 65535 };
40static int tcp_adv_win_scale_min = -31;
41static int tcp_adv_win_scale_max = 31;
42static int tcp_min_snd_mss_min = TCP_MIN_SND_MSS;
43static int tcp_min_snd_mss_max = 65535;
44static int ip_privileged_port_min;
45static int ip_privileged_port_max = 65535;
46static int ip_ttl_min = 1;
47static int ip_ttl_max = 255;
48static int tcp_syn_retries_min = 1;
49static int tcp_syn_retries_max = MAX_TCP_SYNCNT;
50static int ip_ping_group_range_min[] = { 0, 0 };
51static int ip_ping_group_range_max[] = { GID_T_MAX, GID_T_MAX };
52static int comp_sack_nr_max = 255;
53static u32 u32_max_div_HZ = UINT_MAX / HZ;
54static int one_day_secs = 24 * 3600;
55
56/* obsolete */
57static int sysctl_tcp_low_latency __read_mostly;
58
59/* Update system visible IP port range */
60static 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. */
75static 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. */
111static 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
145static 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 */
160static 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. */
172static 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
208static 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
225static 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
245static 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
262static 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
282static int proc_tcp_fastopen_key(struct ctl_table *table, int write,
283 void __user *buffer, size_t *lenp,
284 loff_t *ppos)
285{
286 struct net *net = container_of(table->data, struct net,
287 ipv4.sysctl_tcp_fastopen);
288 struct ctl_table tbl = { .maxlen = (TCP_FASTOPEN_KEY_LENGTH * 2 + 10) };
289 struct tcp_fastopen_context *ctxt;
290 u32 user_key[4]; /* 16 bytes, matching TCP_FASTOPEN_KEY_LENGTH */
291 __le32 key[4];
292 int ret, i;
293
294 tbl.data = kmalloc(tbl.maxlen, GFP_KERNEL);
295 if (!tbl.data)
296 return -ENOMEM;
297
298 rcu_read_lock();
299 ctxt = rcu_dereference(net->ipv4.tcp_fastopen_ctx);
300 if (ctxt)
301 memcpy(key, ctxt->key, TCP_FASTOPEN_KEY_LENGTH);
302 else
303 memset(key, 0, sizeof(key));
304 rcu_read_unlock();
305
306 for (i = 0; i < ARRAY_SIZE(key); i++)
307 user_key[i] = le32_to_cpu(key[i]);
308
309 snprintf(tbl.data, tbl.maxlen, "%08x-%08x-%08x-%08x",
310 user_key[0], user_key[1], user_key[2], user_key[3]);
311 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
312
313 if (write && ret == 0) {
314 if (sscanf(tbl.data, "%x-%x-%x-%x", user_key, user_key + 1,
315 user_key + 2, user_key + 3) != 4) {
316 ret = -EINVAL;
317 goto bad_key;
318 }
319
320 for (i = 0; i < ARRAY_SIZE(user_key); i++)
321 key[i] = cpu_to_le32(user_key[i]);
322
323 tcp_fastopen_reset_cipher(net, NULL, key,
324 TCP_FASTOPEN_KEY_LENGTH);
325 }
326
327bad_key:
328 pr_debug("proc FO key set 0x%x-%x-%x-%x <- 0x%s: %u\n",
329 user_key[0], user_key[1], user_key[2], user_key[3],
330 (char *)tbl.data, ret);
331 kfree(tbl.data);
332 return ret;
333}
334
335static void proc_configure_early_demux(int enabled, int protocol)
336{
337 struct net_protocol *ipprot;
338#if IS_ENABLED(CONFIG_IPV6)
339 struct inet6_protocol *ip6prot;
340#endif
341
342 rcu_read_lock();
343
344 ipprot = rcu_dereference(inet_protos[protocol]);
345 if (ipprot)
346 ipprot->early_demux = enabled ? ipprot->early_demux_handler :
347 NULL;
348
349#if IS_ENABLED(CONFIG_IPV6)
350 ip6prot = rcu_dereference(inet6_protos[protocol]);
351 if (ip6prot)
352 ip6prot->early_demux = enabled ? ip6prot->early_demux_handler :
353 NULL;
354#endif
355 rcu_read_unlock();
356}
357
358static int proc_tcp_early_demux(struct ctl_table *table, int write,
359 void __user *buffer, size_t *lenp, loff_t *ppos)
360{
361 int ret = 0;
362
363 ret = proc_dointvec(table, write, buffer, lenp, ppos);
364
365 if (write && !ret) {
366 int enabled = init_net.ipv4.sysctl_tcp_early_demux;
367
368 proc_configure_early_demux(enabled, IPPROTO_TCP);
369 }
370
371 return ret;
372}
373
374static int proc_udp_early_demux(struct ctl_table *table, int write,
375 void __user *buffer, size_t *lenp, loff_t *ppos)
376{
377 int ret = 0;
378
379 ret = proc_dointvec(table, write, buffer, lenp, ppos);
380
381 if (write && !ret) {
382 int enabled = init_net.ipv4.sysctl_udp_early_demux;
383
384 proc_configure_early_demux(enabled, IPPROTO_UDP);
385 }
386
387 return ret;
388}
389
390static int proc_tfo_blackhole_detect_timeout(struct ctl_table *table,
391 int write,
392 void __user *buffer,
393 size_t *lenp, loff_t *ppos)
394{
395 struct net *net = container_of(table->data, struct net,
396 ipv4.sysctl_tcp_fastopen_blackhole_timeout);
397 int ret;
398
399 ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
400 if (write && ret == 0)
401 atomic_set(&net->ipv4.tfo_active_disable_times, 0);
402
403 return ret;
404}
405
406static int proc_tcp_available_ulp(struct ctl_table *ctl,
407 int write,
408 void __user *buffer, size_t *lenp,
409 loff_t *ppos)
410{
411 struct ctl_table tbl = { .maxlen = TCP_ULP_BUF_MAX, };
412 int ret;
413
414 tbl.data = kmalloc(tbl.maxlen, GFP_USER);
415 if (!tbl.data)
416 return -ENOMEM;
417 tcp_get_available_ulp(tbl.data, TCP_ULP_BUF_MAX);
418 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
419 kfree(tbl.data);
420
421 return ret;
422}
423
424#ifdef CONFIG_IP_ROUTE_MULTIPATH
425static int proc_fib_multipath_hash_policy(struct ctl_table *table, int write,
426 void __user *buffer, size_t *lenp,
427 loff_t *ppos)
428{
429 struct net *net = container_of(table->data, struct net,
430 ipv4.sysctl_fib_multipath_hash_policy);
431 int ret;
432
433 ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
434 if (write && ret == 0)
435 call_netevent_notifiers(NETEVENT_IPV4_MPATH_HASH_UPDATE, net);
436
437 return ret;
438}
439#endif
440
441static struct ctl_table ipv4_table[] = {
442 {
443 .procname = "tcp_max_orphans",
444 .data = &sysctl_tcp_max_orphans,
445 .maxlen = sizeof(int),
446 .mode = 0644,
447 .proc_handler = proc_dointvec
448 },
449 {
450 .procname = "inet_peer_threshold",
451 .data = &inet_peer_threshold,
452 .maxlen = sizeof(int),
453 .mode = 0644,
454 .proc_handler = proc_dointvec
455 },
456 {
457 .procname = "inet_peer_minttl",
458 .data = &inet_peer_minttl,
459 .maxlen = sizeof(int),
460 .mode = 0644,
461 .proc_handler = proc_dointvec_jiffies,
462 },
463 {
464 .procname = "inet_peer_maxttl",
465 .data = &inet_peer_maxttl,
466 .maxlen = sizeof(int),
467 .mode = 0644,
468 .proc_handler = proc_dointvec_jiffies,
469 },
470 {
471 .procname = "tcp_mem",
472 .maxlen = sizeof(sysctl_tcp_mem),
473 .data = &sysctl_tcp_mem,
474 .mode = 0644,
475 .proc_handler = proc_doulongvec_minmax,
476 },
477 {
478 .procname = "tcp_low_latency",
479 .data = &sysctl_tcp_low_latency,
480 .maxlen = sizeof(int),
481 .mode = 0644,
482 .proc_handler = proc_dointvec
483 },
484#ifdef CONFIG_NETLABEL
485 {
486 .procname = "cipso_cache_enable",
487 .data = &cipso_v4_cache_enabled,
488 .maxlen = sizeof(int),
489 .mode = 0644,
490 .proc_handler = proc_dointvec,
491 },
492 {
493 .procname = "cipso_cache_bucket_size",
494 .data = &cipso_v4_cache_bucketsize,
495 .maxlen = sizeof(int),
496 .mode = 0644,
497 .proc_handler = proc_dointvec,
498 },
499 {
500 .procname = "cipso_rbm_optfmt",
501 .data = &cipso_v4_rbm_optfmt,
502 .maxlen = sizeof(int),
503 .mode = 0644,
504 .proc_handler = proc_dointvec,
505 },
506 {
507 .procname = "cipso_rbm_strictvalid",
508 .data = &cipso_v4_rbm_strictvalid,
509 .maxlen = sizeof(int),
510 .mode = 0644,
511 .proc_handler = proc_dointvec,
512 },
513#endif /* CONFIG_NETLABEL */
514 {
515 .procname = "tcp_available_congestion_control",
516 .maxlen = TCP_CA_BUF_MAX,
517 .mode = 0444,
518 .proc_handler = proc_tcp_available_congestion_control,
519 },
520 {
521 .procname = "tcp_allowed_congestion_control",
522 .maxlen = TCP_CA_BUF_MAX,
523 .mode = 0644,
524 .proc_handler = proc_allowed_congestion_control,
525 },
526 {
527 .procname = "tcp_available_ulp",
528 .maxlen = TCP_ULP_BUF_MAX,
529 .mode = 0444,
530 .proc_handler = proc_tcp_available_ulp,
531 },
532 {
533 .procname = "icmp_msgs_per_sec",
534 .data = &sysctl_icmp_msgs_per_sec,
535 .maxlen = sizeof(int),
536 .mode = 0644,
537 .proc_handler = proc_dointvec_minmax,
538 .extra1 = &zero,
539 },
540 {
541 .procname = "icmp_msgs_burst",
542 .data = &sysctl_icmp_msgs_burst,
543 .maxlen = sizeof(int),
544 .mode = 0644,
545 .proc_handler = proc_dointvec_minmax,
546 .extra1 = &zero,
547 },
548 {
549 .procname = "udp_mem",
550 .data = &sysctl_udp_mem,
551 .maxlen = sizeof(sysctl_udp_mem),
552 .mode = 0644,
553 .proc_handler = proc_doulongvec_minmax,
554 },
555 {
556 .procname = "fib_sync_mem",
557 .data = &sysctl_fib_sync_mem,
558 .maxlen = sizeof(sysctl_fib_sync_mem),
559 .mode = 0644,
560 .proc_handler = proc_douintvec_minmax,
561 .extra1 = &sysctl_fib_sync_mem_min,
562 .extra2 = &sysctl_fib_sync_mem_max,
563 },
564 {
565 .procname = "tcp_rx_skb_cache",
566 .data = &tcp_rx_skb_cache_key.key,
567 .mode = 0644,
568 .proc_handler = proc_do_static_key,
569 },
570 {
571 .procname = "tcp_tx_skb_cache",
572 .data = &tcp_tx_skb_cache_key.key,
573 .mode = 0644,
574 .proc_handler = proc_do_static_key,
575 },
576 { }
577};
578
579static struct ctl_table ipv4_net_table[] = {
580 {
581 .procname = "icmp_echo_ignore_all",
582 .data = &init_net.ipv4.sysctl_icmp_echo_ignore_all,
583 .maxlen = sizeof(int),
584 .mode = 0644,
585 .proc_handler = proc_dointvec
586 },
587 {
588 .procname = "icmp_echo_ignore_broadcasts",
589 .data = &init_net.ipv4.sysctl_icmp_echo_ignore_broadcasts,
590 .maxlen = sizeof(int),
591 .mode = 0644,
592 .proc_handler = proc_dointvec
593 },
594 {
595 .procname = "icmp_ignore_bogus_error_responses",
596 .data = &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses,
597 .maxlen = sizeof(int),
598 .mode = 0644,
599 .proc_handler = proc_dointvec
600 },
601 {
602 .procname = "icmp_errors_use_inbound_ifaddr",
603 .data = &init_net.ipv4.sysctl_icmp_errors_use_inbound_ifaddr,
604 .maxlen = sizeof(int),
605 .mode = 0644,
606 .proc_handler = proc_dointvec
607 },
608 {
609 .procname = "icmp_ratelimit",
610 .data = &init_net.ipv4.sysctl_icmp_ratelimit,
611 .maxlen = sizeof(int),
612 .mode = 0644,
613 .proc_handler = proc_dointvec_ms_jiffies,
614 },
615 {
616 .procname = "icmp_ratemask",
617 .data = &init_net.ipv4.sysctl_icmp_ratemask,
618 .maxlen = sizeof(int),
619 .mode = 0644,
620 .proc_handler = proc_dointvec
621 },
622 {
623 .procname = "ping_group_range",
624 .data = &init_net.ipv4.ping_group_range.range,
625 .maxlen = sizeof(gid_t)*2,
626 .mode = 0644,
627 .proc_handler = ipv4_ping_group_range,
628 },
629#ifdef CONFIG_NET_L3_MASTER_DEV
630 {
631 .procname = "raw_l3mdev_accept",
632 .data = &init_net.ipv4.sysctl_raw_l3mdev_accept,
633 .maxlen = sizeof(int),
634 .mode = 0644,
635 .proc_handler = proc_dointvec_minmax,
636 .extra1 = &zero,
637 .extra2 = &one,
638 },
639#endif
640 {
641 .procname = "tcp_ecn",
642 .data = &init_net.ipv4.sysctl_tcp_ecn,
643 .maxlen = sizeof(int),
644 .mode = 0644,
645 .proc_handler = proc_dointvec
646 },
647 {
648 .procname = "tcp_ecn_fallback",
649 .data = &init_net.ipv4.sysctl_tcp_ecn_fallback,
650 .maxlen = sizeof(int),
651 .mode = 0644,
652 .proc_handler = proc_dointvec
653 },
654 {
655 .procname = "ip_dynaddr",
656 .data = &init_net.ipv4.sysctl_ip_dynaddr,
657 .maxlen = sizeof(int),
658 .mode = 0644,
659 .proc_handler = proc_dointvec
660 },
661 {
662 .procname = "ip_early_demux",
663 .data = &init_net.ipv4.sysctl_ip_early_demux,
664 .maxlen = sizeof(int),
665 .mode = 0644,
666 .proc_handler = proc_dointvec
667 },
668 {
669 .procname = "udp_early_demux",
670 .data = &init_net.ipv4.sysctl_udp_early_demux,
671 .maxlen = sizeof(int),
672 .mode = 0644,
673 .proc_handler = proc_udp_early_demux
674 },
675 {
676 .procname = "tcp_early_demux",
677 .data = &init_net.ipv4.sysctl_tcp_early_demux,
678 .maxlen = sizeof(int),
679 .mode = 0644,
680 .proc_handler = proc_tcp_early_demux
681 },
682 {
683 .procname = "ip_default_ttl",
684 .data = &init_net.ipv4.sysctl_ip_default_ttl,
685 .maxlen = sizeof(int),
686 .mode = 0644,
687 .proc_handler = proc_dointvec_minmax,
688 .extra1 = &ip_ttl_min,
689 .extra2 = &ip_ttl_max,
690 },
691 {
692 .procname = "ip_local_port_range",
693 .maxlen = sizeof(init_net.ipv4.ip_local_ports.range),
694 .data = &init_net.ipv4.ip_local_ports.range,
695 .mode = 0644,
696 .proc_handler = ipv4_local_port_range,
697 },
698 {
699 .procname = "ip_local_reserved_ports",
700 .data = &init_net.ipv4.sysctl_local_reserved_ports,
701 .maxlen = 65536,
702 .mode = 0644,
703 .proc_handler = proc_do_large_bitmap,
704 },
705 {
706 .procname = "ip_no_pmtu_disc",
707 .data = &init_net.ipv4.sysctl_ip_no_pmtu_disc,
708 .maxlen = sizeof(int),
709 .mode = 0644,
710 .proc_handler = proc_dointvec
711 },
712 {
713 .procname = "ip_forward_use_pmtu",
714 .data = &init_net.ipv4.sysctl_ip_fwd_use_pmtu,
715 .maxlen = sizeof(int),
716 .mode = 0644,
717 .proc_handler = proc_dointvec,
718 },
719 {
720 .procname = "ip_forward_update_priority",
721 .data = &init_net.ipv4.sysctl_ip_fwd_update_priority,
722 .maxlen = sizeof(int),
723 .mode = 0644,
724 .proc_handler = ipv4_fwd_update_priority,
725 .extra1 = &zero,
726 .extra2 = &one,
727 },
728 {
729 .procname = "ip_nonlocal_bind",
730 .data = &init_net.ipv4.sysctl_ip_nonlocal_bind,
731 .maxlen = sizeof(int),
732 .mode = 0644,
733 .proc_handler = proc_dointvec
734 },
735 {
736 .procname = "fwmark_reflect",
737 .data = &init_net.ipv4.sysctl_fwmark_reflect,
738 .maxlen = sizeof(int),
739 .mode = 0644,
740 .proc_handler = proc_dointvec,
741 },
742 {
743 .procname = "tcp_fwmark_accept",
744 .data = &init_net.ipv4.sysctl_tcp_fwmark_accept,
745 .maxlen = sizeof(int),
746 .mode = 0644,
747 .proc_handler = proc_dointvec,
748 },
749#ifdef CONFIG_NET_L3_MASTER_DEV
750 {
751 .procname = "tcp_l3mdev_accept",
752 .data = &init_net.ipv4.sysctl_tcp_l3mdev_accept,
753 .maxlen = sizeof(int),
754 .mode = 0644,
755 .proc_handler = proc_dointvec_minmax,
756 .extra1 = &zero,
757 .extra2 = &one,
758 },
759#endif
760 {
761 .procname = "tcp_mtu_probing",
762 .data = &init_net.ipv4.sysctl_tcp_mtu_probing,
763 .maxlen = sizeof(int),
764 .mode = 0644,
765 .proc_handler = proc_dointvec,
766 },
767 {
768 .procname = "tcp_base_mss",
769 .data = &init_net.ipv4.sysctl_tcp_base_mss,
770 .maxlen = sizeof(int),
771 .mode = 0644,
772 .proc_handler = proc_dointvec,
773 },
774 {
775 .procname = "tcp_min_snd_mss",
776 .data = &init_net.ipv4.sysctl_tcp_min_snd_mss,
777 .maxlen = sizeof(int),
778 .mode = 0644,
779 .proc_handler = proc_dointvec_minmax,
780 .extra1 = &tcp_min_snd_mss_min,
781 .extra2 = &tcp_min_snd_mss_max,
782 },
783 {
784 .procname = "tcp_probe_threshold",
785 .data = &init_net.ipv4.sysctl_tcp_probe_threshold,
786 .maxlen = sizeof(int),
787 .mode = 0644,
788 .proc_handler = proc_dointvec,
789 },
790 {
791 .procname = "tcp_probe_interval",
792 .data = &init_net.ipv4.sysctl_tcp_probe_interval,
793 .maxlen = sizeof(u32),
794 .mode = 0644,
795 .proc_handler = proc_douintvec_minmax,
796 .extra2 = &u32_max_div_HZ,
797 },
798 {
799 .procname = "igmp_link_local_mcast_reports",
800 .data = &init_net.ipv4.sysctl_igmp_llm_reports,
801 .maxlen = sizeof(int),
802 .mode = 0644,
803 .proc_handler = proc_dointvec
804 },
805 {
806 .procname = "igmp_max_memberships",
807 .data = &init_net.ipv4.sysctl_igmp_max_memberships,
808 .maxlen = sizeof(int),
809 .mode = 0644,
810 .proc_handler = proc_dointvec
811 },
812 {
813 .procname = "igmp_max_msf",
814 .data = &init_net.ipv4.sysctl_igmp_max_msf,
815 .maxlen = sizeof(int),
816 .mode = 0644,
817 .proc_handler = proc_dointvec
818 },
819#ifdef CONFIG_IP_MULTICAST
820 {
821 .procname = "igmp_qrv",
822 .data = &init_net.ipv4.sysctl_igmp_qrv,
823 .maxlen = sizeof(int),
824 .mode = 0644,
825 .proc_handler = proc_dointvec_minmax,
826 .extra1 = &one
827 },
828#endif
829 {
830 .procname = "tcp_congestion_control",
831 .data = &init_net.ipv4.tcp_congestion_control,
832 .mode = 0644,
833 .maxlen = TCP_CA_NAME_MAX,
834 .proc_handler = proc_tcp_congestion_control,
835 },
836 {
837 .procname = "tcp_keepalive_time",
838 .data = &init_net.ipv4.sysctl_tcp_keepalive_time,
839 .maxlen = sizeof(int),
840 .mode = 0644,
841 .proc_handler = proc_dointvec_jiffies,
842 },
843 {
844 .procname = "tcp_keepalive_probes",
845 .data = &init_net.ipv4.sysctl_tcp_keepalive_probes,
846 .maxlen = sizeof(int),
847 .mode = 0644,
848 .proc_handler = proc_dointvec
849 },
850 {
851 .procname = "tcp_keepalive_intvl",
852 .data = &init_net.ipv4.sysctl_tcp_keepalive_intvl,
853 .maxlen = sizeof(int),
854 .mode = 0644,
855 .proc_handler = proc_dointvec_jiffies,
856 },
857 {
858 .procname = "tcp_syn_retries",
859 .data = &init_net.ipv4.sysctl_tcp_syn_retries,
860 .maxlen = sizeof(int),
861 .mode = 0644,
862 .proc_handler = proc_dointvec_minmax,
863 .extra1 = &tcp_syn_retries_min,
864 .extra2 = &tcp_syn_retries_max
865 },
866 {
867 .procname = "tcp_synack_retries",
868 .data = &init_net.ipv4.sysctl_tcp_synack_retries,
869 .maxlen = sizeof(int),
870 .mode = 0644,
871 .proc_handler = proc_dointvec
872 },
873#ifdef CONFIG_SYN_COOKIES
874 {
875 .procname = "tcp_syncookies",
876 .data = &init_net.ipv4.sysctl_tcp_syncookies,
877 .maxlen = sizeof(int),
878 .mode = 0644,
879 .proc_handler = proc_dointvec
880 },
881#endif
882 {
883 .procname = "tcp_reordering",
884 .data = &init_net.ipv4.sysctl_tcp_reordering,
885 .maxlen = sizeof(int),
886 .mode = 0644,
887 .proc_handler = proc_dointvec
888 },
889 {
890 .procname = "tcp_retries1",
891 .data = &init_net.ipv4.sysctl_tcp_retries1,
892 .maxlen = sizeof(int),
893 .mode = 0644,
894 .proc_handler = proc_dointvec_minmax,
895 .extra2 = &tcp_retr1_max
896 },
897 {
898 .procname = "tcp_retries2",
899 .data = &init_net.ipv4.sysctl_tcp_retries2,
900 .maxlen = sizeof(int),
901 .mode = 0644,
902 .proc_handler = proc_dointvec
903 },
904 {
905 .procname = "tcp_orphan_retries",
906 .data = &init_net.ipv4.sysctl_tcp_orphan_retries,
907 .maxlen = sizeof(int),
908 .mode = 0644,
909 .proc_handler = proc_dointvec
910 },
911 {
912 .procname = "tcp_fin_timeout",
913 .data = &init_net.ipv4.sysctl_tcp_fin_timeout,
914 .maxlen = sizeof(int),
915 .mode = 0644,
916 .proc_handler = proc_dointvec_jiffies,
917 },
918 {
919 .procname = "tcp_notsent_lowat",
920 .data = &init_net.ipv4.sysctl_tcp_notsent_lowat,
921 .maxlen = sizeof(unsigned int),
922 .mode = 0644,
923 .proc_handler = proc_douintvec,
924 },
925 {
926 .procname = "tcp_tw_reuse",
927 .data = &init_net.ipv4.sysctl_tcp_tw_reuse,
928 .maxlen = sizeof(int),
929 .mode = 0644,
930 .proc_handler = proc_dointvec_minmax,
931 .extra1 = &zero,
932 .extra2 = &two,
933 },
934 {
935 .procname = "tcp_max_tw_buckets",
936 .data = &init_net.ipv4.tcp_death_row.sysctl_max_tw_buckets,
937 .maxlen = sizeof(int),
938 .mode = 0644,
939 .proc_handler = proc_dointvec
940 },
941 {
942 .procname = "tcp_max_syn_backlog",
943 .data = &init_net.ipv4.sysctl_max_syn_backlog,
944 .maxlen = sizeof(int),
945 .mode = 0644,
946 .proc_handler = proc_dointvec
947 },
948 {
949 .procname = "tcp_fastopen",
950 .data = &init_net.ipv4.sysctl_tcp_fastopen,
951 .maxlen = sizeof(int),
952 .mode = 0644,
953 .proc_handler = proc_dointvec,
954 },
955 {
956 .procname = "tcp_fastopen_key",
957 .mode = 0600,
958 .data = &init_net.ipv4.sysctl_tcp_fastopen,
959 .maxlen = ((TCP_FASTOPEN_KEY_LENGTH * 2) + 10),
960 .proc_handler = proc_tcp_fastopen_key,
961 },
962 {
963 .procname = "tcp_fastopen_blackhole_timeout_sec",
964 .data = &init_net.ipv4.sysctl_tcp_fastopen_blackhole_timeout,
965 .maxlen = sizeof(int),
966 .mode = 0644,
967 .proc_handler = proc_tfo_blackhole_detect_timeout,
968 .extra1 = &zero,
969 },
970#ifdef CONFIG_IP_ROUTE_MULTIPATH
971 {
972 .procname = "fib_multipath_use_neigh",
973 .data = &init_net.ipv4.sysctl_fib_multipath_use_neigh,
974 .maxlen = sizeof(int),
975 .mode = 0644,
976 .proc_handler = proc_dointvec_minmax,
977 .extra1 = &zero,
978 .extra2 = &one,
979 },
980 {
981 .procname = "fib_multipath_hash_policy",
982 .data = &init_net.ipv4.sysctl_fib_multipath_hash_policy,
983 .maxlen = sizeof(int),
984 .mode = 0644,
985 .proc_handler = proc_fib_multipath_hash_policy,
986 .extra1 = &zero,
987 .extra2 = &one,
988 },
989#endif
990 {
991 .procname = "ip_unprivileged_port_start",
992 .maxlen = sizeof(int),
993 .data = &init_net.ipv4.sysctl_ip_prot_sock,
994 .mode = 0644,
995 .proc_handler = ipv4_privileged_ports,
996 },
997#ifdef CONFIG_NET_L3_MASTER_DEV
998 {
999 .procname = "udp_l3mdev_accept",
1000 .data = &init_net.ipv4.sysctl_udp_l3mdev_accept,
1001 .maxlen = sizeof(int),
1002 .mode = 0644,
1003 .proc_handler = proc_dointvec_minmax,
1004 .extra1 = &zero,
1005 .extra2 = &one,
1006 },
1007#endif
1008 {
1009 .procname = "tcp_sack",
1010 .data = &init_net.ipv4.sysctl_tcp_sack,
1011 .maxlen = sizeof(int),
1012 .mode = 0644,
1013 .proc_handler = proc_dointvec
1014 },
1015 {
1016 .procname = "tcp_window_scaling",
1017 .data = &init_net.ipv4.sysctl_tcp_window_scaling,
1018 .maxlen = sizeof(int),
1019 .mode = 0644,
1020 .proc_handler = proc_dointvec
1021 },
1022 {
1023 .procname = "tcp_timestamps",
1024 .data = &init_net.ipv4.sysctl_tcp_timestamps,
1025 .maxlen = sizeof(int),
1026 .mode = 0644,
1027 .proc_handler = proc_dointvec
1028 },
1029 {
1030 .procname = "tcp_early_retrans",
1031 .data = &init_net.ipv4.sysctl_tcp_early_retrans,
1032 .maxlen = sizeof(int),
1033 .mode = 0644,
1034 .proc_handler = proc_dointvec_minmax,
1035 .extra1 = &zero,
1036 .extra2 = &four,
1037 },
1038 {
1039 .procname = "tcp_recovery",
1040 .data = &init_net.ipv4.sysctl_tcp_recovery,
1041 .maxlen = sizeof(int),
1042 .mode = 0644,
1043 .proc_handler = proc_dointvec,
1044 },
1045 {
1046 .procname = "tcp_thin_linear_timeouts",
1047 .data = &init_net.ipv4.sysctl_tcp_thin_linear_timeouts,
1048 .maxlen = sizeof(int),
1049 .mode = 0644,
1050 .proc_handler = proc_dointvec
1051 },
1052 {
1053 .procname = "tcp_slow_start_after_idle",
1054 .data = &init_net.ipv4.sysctl_tcp_slow_start_after_idle,
1055 .maxlen = sizeof(int),
1056 .mode = 0644,
1057 .proc_handler = proc_dointvec
1058 },
1059 {
1060 .procname = "tcp_retrans_collapse",
1061 .data = &init_net.ipv4.sysctl_tcp_retrans_collapse,
1062 .maxlen = sizeof(int),
1063 .mode = 0644,
1064 .proc_handler = proc_dointvec
1065 },
1066 {
1067 .procname = "tcp_stdurg",
1068 .data = &init_net.ipv4.sysctl_tcp_stdurg,
1069 .maxlen = sizeof(int),
1070 .mode = 0644,
1071 .proc_handler = proc_dointvec
1072 },
1073 {
1074 .procname = "tcp_rfc1337",
1075 .data = &init_net.ipv4.sysctl_tcp_rfc1337,
1076 .maxlen = sizeof(int),
1077 .mode = 0644,
1078 .proc_handler = proc_dointvec
1079 },
1080 {
1081 .procname = "tcp_abort_on_overflow",
1082 .data = &init_net.ipv4.sysctl_tcp_abort_on_overflow,
1083 .maxlen = sizeof(int),
1084 .mode = 0644,
1085 .proc_handler = proc_dointvec
1086 },
1087 {
1088 .procname = "tcp_fack",
1089 .data = &init_net.ipv4.sysctl_tcp_fack,
1090 .maxlen = sizeof(int),
1091 .mode = 0644,
1092 .proc_handler = proc_dointvec
1093 },
1094 {
1095 .procname = "tcp_max_reordering",
1096 .data = &init_net.ipv4.sysctl_tcp_max_reordering,
1097 .maxlen = sizeof(int),
1098 .mode = 0644,
1099 .proc_handler = proc_dointvec
1100 },
1101 {
1102 .procname = "tcp_dsack",
1103 .data = &init_net.ipv4.sysctl_tcp_dsack,
1104 .maxlen = sizeof(int),
1105 .mode = 0644,
1106 .proc_handler = proc_dointvec
1107 },
1108 {
1109 .procname = "tcp_app_win",
1110 .data = &init_net.ipv4.sysctl_tcp_app_win,
1111 .maxlen = sizeof(int),
1112 .mode = 0644,
1113 .proc_handler = proc_dointvec
1114 },
1115 {
1116 .procname = "tcp_adv_win_scale",
1117 .data = &init_net.ipv4.sysctl_tcp_adv_win_scale,
1118 .maxlen = sizeof(int),
1119 .mode = 0644,
1120 .proc_handler = proc_dointvec_minmax,
1121 .extra1 = &tcp_adv_win_scale_min,
1122 .extra2 = &tcp_adv_win_scale_max,
1123 },
1124 {
1125 .procname = "tcp_frto",
1126 .data = &init_net.ipv4.sysctl_tcp_frto,
1127 .maxlen = sizeof(int),
1128 .mode = 0644,
1129 .proc_handler = proc_dointvec
1130 },
1131 {
1132 .procname = "tcp_no_metrics_save",
1133 .data = &init_net.ipv4.sysctl_tcp_nometrics_save,
1134 .maxlen = sizeof(int),
1135 .mode = 0644,
1136 .proc_handler = proc_dointvec,
1137 },
1138 {
1139 .procname = "tcp_moderate_rcvbuf",
1140 .data = &init_net.ipv4.sysctl_tcp_moderate_rcvbuf,
1141 .maxlen = sizeof(int),
1142 .mode = 0644,
1143 .proc_handler = proc_dointvec,
1144 },
1145 {
1146 .procname = "tcp_tso_win_divisor",
1147 .data = &init_net.ipv4.sysctl_tcp_tso_win_divisor,
1148 .maxlen = sizeof(int),
1149 .mode = 0644,
1150 .proc_handler = proc_dointvec,
1151 },
1152 {
1153 .procname = "tcp_workaround_signed_windows",
1154 .data = &init_net.ipv4.sysctl_tcp_workaround_signed_windows,
1155 .maxlen = sizeof(int),
1156 .mode = 0644,
1157 .proc_handler = proc_dointvec
1158 },
1159 {
1160 .procname = "tcp_limit_output_bytes",
1161 .data = &init_net.ipv4.sysctl_tcp_limit_output_bytes,
1162 .maxlen = sizeof(int),
1163 .mode = 0644,
1164 .proc_handler = proc_dointvec
1165 },
1166 {
1167 .procname = "tcp_challenge_ack_limit",
1168 .data = &init_net.ipv4.sysctl_tcp_challenge_ack_limit,
1169 .maxlen = sizeof(int),
1170 .mode = 0644,
1171 .proc_handler = proc_dointvec
1172 },
1173 {
1174 .procname = "tcp_min_tso_segs",
1175 .data = &init_net.ipv4.sysctl_tcp_min_tso_segs,
1176 .maxlen = sizeof(int),
1177 .mode = 0644,
1178 .proc_handler = proc_dointvec_minmax,
1179 .extra1 = &one,
1180 .extra2 = &gso_max_segs,
1181 },
1182 {
1183 .procname = "tcp_min_rtt_wlen",
1184 .data = &init_net.ipv4.sysctl_tcp_min_rtt_wlen,
1185 .maxlen = sizeof(int),
1186 .mode = 0644,
1187 .proc_handler = proc_dointvec_minmax,
1188 .extra1 = &zero,
1189 .extra2 = &one_day_secs
1190 },
1191 {
1192 .procname = "tcp_autocorking",
1193 .data = &init_net.ipv4.sysctl_tcp_autocorking,
1194 .maxlen = sizeof(int),
1195 .mode = 0644,
1196 .proc_handler = proc_dointvec_minmax,
1197 .extra1 = &zero,
1198 .extra2 = &one,
1199 },
1200 {
1201 .procname = "tcp_invalid_ratelimit",
1202 .data = &init_net.ipv4.sysctl_tcp_invalid_ratelimit,
1203 .maxlen = sizeof(int),
1204 .mode = 0644,
1205 .proc_handler = proc_dointvec_ms_jiffies,
1206 },
1207 {
1208 .procname = "tcp_pacing_ss_ratio",
1209 .data = &init_net.ipv4.sysctl_tcp_pacing_ss_ratio,
1210 .maxlen = sizeof(int),
1211 .mode = 0644,
1212 .proc_handler = proc_dointvec_minmax,
1213 .extra1 = &zero,
1214 .extra2 = &thousand,
1215 },
1216 {
1217 .procname = "tcp_pacing_ca_ratio",
1218 .data = &init_net.ipv4.sysctl_tcp_pacing_ca_ratio,
1219 .maxlen = sizeof(int),
1220 .mode = 0644,
1221 .proc_handler = proc_dointvec_minmax,
1222 .extra1 = &zero,
1223 .extra2 = &thousand,
1224 },
1225 {
1226 .procname = "tcp_wmem",
1227 .data = &init_net.ipv4.sysctl_tcp_wmem,
1228 .maxlen = sizeof(init_net.ipv4.sysctl_tcp_wmem),
1229 .mode = 0644,
1230 .proc_handler = proc_dointvec_minmax,
1231 .extra1 = &one,
1232 },
1233 {
1234 .procname = "tcp_rmem",
1235 .data = &init_net.ipv4.sysctl_tcp_rmem,
1236 .maxlen = sizeof(init_net.ipv4.sysctl_tcp_rmem),
1237 .mode = 0644,
1238 .proc_handler = proc_dointvec_minmax,
1239 .extra1 = &one,
1240 },
1241 {
1242 .procname = "tcp_comp_sack_delay_ns",
1243 .data = &init_net.ipv4.sysctl_tcp_comp_sack_delay_ns,
1244 .maxlen = sizeof(unsigned long),
1245 .mode = 0644,
1246 .proc_handler = proc_doulongvec_minmax,
1247 },
1248 {
1249 .procname = "tcp_comp_sack_nr",
1250 .data = &init_net.ipv4.sysctl_tcp_comp_sack_nr,
1251 .maxlen = sizeof(int),
1252 .mode = 0644,
1253 .proc_handler = proc_dointvec_minmax,
1254 .extra1 = &zero,
1255 .extra2 = &comp_sack_nr_max,
1256 },
1257 {
1258 .procname = "udp_rmem_min",
1259 .data = &init_net.ipv4.sysctl_udp_rmem_min,
1260 .maxlen = sizeof(init_net.ipv4.sysctl_udp_rmem_min),
1261 .mode = 0644,
1262 .proc_handler = proc_dointvec_minmax,
1263 .extra1 = &one
1264 },
1265 {
1266 .procname = "udp_wmem_min",
1267 .data = &init_net.ipv4.sysctl_udp_wmem_min,
1268 .maxlen = sizeof(init_net.ipv4.sysctl_udp_wmem_min),
1269 .mode = 0644,
1270 .proc_handler = proc_dointvec_minmax,
1271 .extra1 = &one
1272 },
1273 { }
1274};
1275
1276static __net_init int ipv4_sysctl_init_net(struct net *net)
1277{
1278 struct ctl_table *table;
1279
1280 table = ipv4_net_table;
1281 if (!net_eq(net, &init_net)) {
1282 int i;
1283
1284 table = kmemdup(table, sizeof(ipv4_net_table), GFP_KERNEL);
1285 if (!table)
1286 goto err_alloc;
1287
1288 /* Update the variables to point into the current struct net */
1289 for (i = 0; i < ARRAY_SIZE(ipv4_net_table) - 1; i++)
1290 table[i].data += (void *)net - (void *)&init_net;
1291 }
1292
1293 net->ipv4.ipv4_hdr = register_net_sysctl(net, "net/ipv4", table);
1294 if (!net->ipv4.ipv4_hdr)
1295 goto err_reg;
1296
1297 net->ipv4.sysctl_local_reserved_ports = kzalloc(65536 / 8, GFP_KERNEL);
1298 if (!net->ipv4.sysctl_local_reserved_ports)
1299 goto err_ports;
1300
1301 return 0;
1302
1303err_ports:
1304 unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
1305err_reg:
1306 if (!net_eq(net, &init_net))
1307 kfree(table);
1308err_alloc:
1309 return -ENOMEM;
1310}
1311
1312static __net_exit void ipv4_sysctl_exit_net(struct net *net)
1313{
1314 struct ctl_table *table;
1315
1316 kfree(net->ipv4.sysctl_local_reserved_ports);
1317 table = net->ipv4.ipv4_hdr->ctl_table_arg;
1318 unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
1319 kfree(table);
1320}
1321
1322static __net_initdata struct pernet_operations ipv4_sysctl_ops = {
1323 .init = ipv4_sysctl_init_net,
1324 .exit = ipv4_sysctl_exit_net,
1325};
1326
1327static __init int sysctl_ipv4_init(void)
1328{
1329 struct ctl_table_header *hdr;
1330
1331 hdr = register_net_sysctl(&init_net, "net/ipv4", ipv4_table);
1332 if (!hdr)
1333 return -ENOMEM;
1334
1335 if (register_pernet_subsys(&ipv4_sysctl_ops)) {
1336 unregister_net_sysctl_table(hdr);
1337 return -ENOMEM;
1338 }
1339
1340 return 0;
1341}
1342
1343__initcall(sysctl_ipv4_init);