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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 four = 4;
34static int thousand = 1000;
35static int gso_max_segs = GSO_MAX_SEGS;
36static int tcp_retr1_max = 255;
37static int ip_local_port_range_min[] = { 1, 1 };
38static int ip_local_port_range_max[] = { 65535, 65535 };
39static int tcp_adv_win_scale_min = -31;
40static int tcp_adv_win_scale_max = 31;
41static int ip_privileged_port_min;
42static int ip_privileged_port_max = 65535;
43static int ip_ttl_min = 1;
44static int ip_ttl_max = 255;
45static int tcp_syn_retries_min = 1;
46static int tcp_syn_retries_max = MAX_TCP_SYNCNT;
47static int ip_ping_group_range_min[] = { 0, 0 };
48static int ip_ping_group_range_max[] = { GID_T_MAX, GID_T_MAX };
49
50/* obsolete */
51static int sysctl_tcp_low_latency __read_mostly;
52
53/* Update system visible IP port range */
54static void set_local_port_range(struct net *net, int range[2])
55{
56 bool same_parity = !((range[0] ^ range[1]) & 1);
57
58 write_seqlock_bh(&net->ipv4.ip_local_ports.lock);
59 if (same_parity && !net->ipv4.ip_local_ports.warned) {
60 net->ipv4.ip_local_ports.warned = true;
61 pr_err_ratelimited("ip_local_port_range: prefer different parity for start/end values.\n");
62 }
63 net->ipv4.ip_local_ports.range[0] = range[0];
64 net->ipv4.ip_local_ports.range[1] = range[1];
65 write_sequnlock_bh(&net->ipv4.ip_local_ports.lock);
66}
67
68/* Validate changes from /proc interface. */
69static int ipv4_local_port_range(struct ctl_table *table, int write,
70 void __user *buffer,
71 size_t *lenp, loff_t *ppos)
72{
73 struct net *net =
74 container_of(table->data, struct net, ipv4.ip_local_ports.range);
75 int ret;
76 int range[2];
77 struct ctl_table tmp = {
78 .data = &range,
79 .maxlen = sizeof(range),
80 .mode = table->mode,
81 .extra1 = &ip_local_port_range_min,
82 .extra2 = &ip_local_port_range_max,
83 };
84
85 inet_get_local_port_range(net, &range[0], &range[1]);
86
87 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
88
89 if (write && ret == 0) {
90 /* Ensure that the upper limit is not smaller than the lower,
91 * and that the lower does not encroach upon the privileged
92 * port limit.
93 */
94 if ((range[1] < range[0]) ||
95 (range[0] < net->ipv4.sysctl_ip_prot_sock))
96 ret = -EINVAL;
97 else
98 set_local_port_range(net, range);
99 }
100
101 return ret;
102}
103
104/* Validate changes from /proc interface. */
105static int ipv4_privileged_ports(struct ctl_table *table, int write,
106 void __user *buffer, size_t *lenp, loff_t *ppos)
107{
108 struct net *net = container_of(table->data, struct net,
109 ipv4.sysctl_ip_prot_sock);
110 int ret;
111 int pports;
112 int range[2];
113 struct ctl_table tmp = {
114 .data = &pports,
115 .maxlen = sizeof(pports),
116 .mode = table->mode,
117 .extra1 = &ip_privileged_port_min,
118 .extra2 = &ip_privileged_port_max,
119 };
120
121 pports = net->ipv4.sysctl_ip_prot_sock;
122
123 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
124
125 if (write && ret == 0) {
126 inet_get_local_port_range(net, &range[0], &range[1]);
127 /* Ensure that the local port range doesn't overlap with the
128 * privileged port range.
129 */
130 if (range[0] < pports)
131 ret = -EINVAL;
132 else
133 net->ipv4.sysctl_ip_prot_sock = pports;
134 }
135
136 return ret;
137}
138
139static void inet_get_ping_group_range_table(struct ctl_table *table, kgid_t *low, kgid_t *high)
140{
141 kgid_t *data = table->data;
142 struct net *net =
143 container_of(table->data, struct net, ipv4.ping_group_range.range);
144 unsigned int seq;
145 do {
146 seq = read_seqbegin(&net->ipv4.ping_group_range.lock);
147
148 *low = data[0];
149 *high = data[1];
150 } while (read_seqretry(&net->ipv4.ping_group_range.lock, seq));
151}
152
153/* Update system visible IP port range */
154static void set_ping_group_range(struct ctl_table *table, kgid_t low, kgid_t high)
155{
156 kgid_t *data = table->data;
157 struct net *net =
158 container_of(table->data, struct net, ipv4.ping_group_range.range);
159 write_seqlock(&net->ipv4.ping_group_range.lock);
160 data[0] = low;
161 data[1] = high;
162 write_sequnlock(&net->ipv4.ping_group_range.lock);
163}
164
165/* Validate changes from /proc interface. */
166static int ipv4_ping_group_range(struct ctl_table *table, int write,
167 void __user *buffer,
168 size_t *lenp, loff_t *ppos)
169{
170 struct user_namespace *user_ns = current_user_ns();
171 int ret;
172 gid_t urange[2];
173 kgid_t low, high;
174 struct ctl_table tmp = {
175 .data = &urange,
176 .maxlen = sizeof(urange),
177 .mode = table->mode,
178 .extra1 = &ip_ping_group_range_min,
179 .extra2 = &ip_ping_group_range_max,
180 };
181
182 inet_get_ping_group_range_table(table, &low, &high);
183 urange[0] = from_kgid_munged(user_ns, low);
184 urange[1] = from_kgid_munged(user_ns, high);
185 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
186
187 if (write && ret == 0) {
188 low = make_kgid(user_ns, urange[0]);
189 high = make_kgid(user_ns, urange[1]);
190 if (!gid_valid(low) || !gid_valid(high) ||
191 (urange[1] < urange[0]) || gid_lt(high, low)) {
192 low = make_kgid(&init_user_ns, 1);
193 high = make_kgid(&init_user_ns, 0);
194 }
195 set_ping_group_range(table, low, high);
196 }
197
198 return ret;
199}
200
201static int proc_tcp_congestion_control(struct ctl_table *ctl, int write,
202 void __user *buffer, size_t *lenp, loff_t *ppos)
203{
204 struct net *net = container_of(ctl->data, struct net,
205 ipv4.tcp_congestion_control);
206 char val[TCP_CA_NAME_MAX];
207 struct ctl_table tbl = {
208 .data = val,
209 .maxlen = TCP_CA_NAME_MAX,
210 };
211 int ret;
212
213 tcp_get_default_congestion_control(net, val);
214
215 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
216 if (write && ret == 0)
217 ret = tcp_set_default_congestion_control(net, val);
218 return ret;
219}
220
221static int proc_tcp_available_congestion_control(struct ctl_table *ctl,
222 int write,
223 void __user *buffer, size_t *lenp,
224 loff_t *ppos)
225{
226 struct ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX, };
227 int ret;
228
229 tbl.data = kmalloc(tbl.maxlen, GFP_USER);
230 if (!tbl.data)
231 return -ENOMEM;
232 tcp_get_available_congestion_control(tbl.data, TCP_CA_BUF_MAX);
233 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
234 kfree(tbl.data);
235 return ret;
236}
237
238static int proc_allowed_congestion_control(struct ctl_table *ctl,
239 int write,
240 void __user *buffer, size_t *lenp,
241 loff_t *ppos)
242{
243 struct ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX };
244 int ret;
245
246 tbl.data = kmalloc(tbl.maxlen, GFP_USER);
247 if (!tbl.data)
248 return -ENOMEM;
249
250 tcp_get_allowed_congestion_control(tbl.data, tbl.maxlen);
251 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
252 if (write && ret == 0)
253 ret = tcp_set_allowed_congestion_control(tbl.data);
254 kfree(tbl.data);
255 return ret;
256}
257
258static int proc_tcp_fastopen_key(struct ctl_table *table, int write,
259 void __user *buffer, size_t *lenp,
260 loff_t *ppos)
261{
262 struct net *net = container_of(table->data, struct net,
263 ipv4.sysctl_tcp_fastopen);
264 struct ctl_table tbl = { .maxlen = (TCP_FASTOPEN_KEY_LENGTH * 2 + 10) };
265 struct tcp_fastopen_context *ctxt;
266 int ret;
267 u32 user_key[4]; /* 16 bytes, matching TCP_FASTOPEN_KEY_LENGTH */
268
269 tbl.data = kmalloc(tbl.maxlen, GFP_KERNEL);
270 if (!tbl.data)
271 return -ENOMEM;
272
273 rcu_read_lock();
274 ctxt = rcu_dereference(net->ipv4.tcp_fastopen_ctx);
275 if (ctxt)
276 memcpy(user_key, ctxt->key, TCP_FASTOPEN_KEY_LENGTH);
277 else
278 memset(user_key, 0, sizeof(user_key));
279 rcu_read_unlock();
280
281 snprintf(tbl.data, tbl.maxlen, "%08x-%08x-%08x-%08x",
282 user_key[0], user_key[1], user_key[2], user_key[3]);
283 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
284
285 if (write && ret == 0) {
286 if (sscanf(tbl.data, "%x-%x-%x-%x", user_key, user_key + 1,
287 user_key + 2, user_key + 3) != 4) {
288 ret = -EINVAL;
289 goto bad_key;
290 }
291 tcp_fastopen_reset_cipher(net, NULL, user_key,
292 TCP_FASTOPEN_KEY_LENGTH);
293 }
294
295bad_key:
296 pr_debug("proc FO key set 0x%x-%x-%x-%x <- 0x%s: %u\n",
297 user_key[0], user_key[1], user_key[2], user_key[3],
298 (char *)tbl.data, ret);
299 kfree(tbl.data);
300 return ret;
301}
302
303static void proc_configure_early_demux(int enabled, int protocol)
304{
305 struct net_protocol *ipprot;
306#if IS_ENABLED(CONFIG_IPV6)
307 struct inet6_protocol *ip6prot;
308#endif
309
310 rcu_read_lock();
311
312 ipprot = rcu_dereference(inet_protos[protocol]);
313 if (ipprot)
314 ipprot->early_demux = enabled ? ipprot->early_demux_handler :
315 NULL;
316
317#if IS_ENABLED(CONFIG_IPV6)
318 ip6prot = rcu_dereference(inet6_protos[protocol]);
319 if (ip6prot)
320 ip6prot->early_demux = enabled ? ip6prot->early_demux_handler :
321 NULL;
322#endif
323 rcu_read_unlock();
324}
325
326static int proc_tcp_early_demux(struct ctl_table *table, int write,
327 void __user *buffer, size_t *lenp, loff_t *ppos)
328{
329 int ret = 0;
330
331 ret = proc_dointvec(table, write, buffer, lenp, ppos);
332
333 if (write && !ret) {
334 int enabled = init_net.ipv4.sysctl_tcp_early_demux;
335
336 proc_configure_early_demux(enabled, IPPROTO_TCP);
337 }
338
339 return ret;
340}
341
342static int proc_udp_early_demux(struct ctl_table *table, int write,
343 void __user *buffer, size_t *lenp, loff_t *ppos)
344{
345 int ret = 0;
346
347 ret = proc_dointvec(table, write, buffer, lenp, ppos);
348
349 if (write && !ret) {
350 int enabled = init_net.ipv4.sysctl_udp_early_demux;
351
352 proc_configure_early_demux(enabled, IPPROTO_UDP);
353 }
354
355 return ret;
356}
357
358static int proc_tfo_blackhole_detect_timeout(struct ctl_table *table,
359 int write,
360 void __user *buffer,
361 size_t *lenp, loff_t *ppos)
362{
363 struct net *net = container_of(table->data, struct net,
364 ipv4.sysctl_tcp_fastopen_blackhole_timeout);
365 int ret;
366
367 ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
368 if (write && ret == 0)
369 atomic_set(&net->ipv4.tfo_active_disable_times, 0);
370
371 return ret;
372}
373
374static int proc_tcp_available_ulp(struct ctl_table *ctl,
375 int write,
376 void __user *buffer, size_t *lenp,
377 loff_t *ppos)
378{
379 struct ctl_table tbl = { .maxlen = TCP_ULP_BUF_MAX, };
380 int ret;
381
382 tbl.data = kmalloc(tbl.maxlen, GFP_USER);
383 if (!tbl.data)
384 return -ENOMEM;
385 tcp_get_available_ulp(tbl.data, TCP_ULP_BUF_MAX);
386 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
387 kfree(tbl.data);
388
389 return ret;
390}
391
392#ifdef CONFIG_IP_ROUTE_MULTIPATH
393static int proc_fib_multipath_hash_policy(struct ctl_table *table, int write,
394 void __user *buffer, size_t *lenp,
395 loff_t *ppos)
396{
397 struct net *net = container_of(table->data, struct net,
398 ipv4.sysctl_fib_multipath_hash_policy);
399 int ret;
400
401 ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
402 if (write && ret == 0)
403 call_netevent_notifiers(NETEVENT_IPV4_MPATH_HASH_UPDATE, net);
404
405 return ret;
406}
407#endif
408
409static struct ctl_table ipv4_table[] = {
410 {
411 .procname = "tcp_max_orphans",
412 .data = &sysctl_tcp_max_orphans,
413 .maxlen = sizeof(int),
414 .mode = 0644,
415 .proc_handler = proc_dointvec
416 },
417 {
418 .procname = "inet_peer_threshold",
419 .data = &inet_peer_threshold,
420 .maxlen = sizeof(int),
421 .mode = 0644,
422 .proc_handler = proc_dointvec
423 },
424 {
425 .procname = "inet_peer_minttl",
426 .data = &inet_peer_minttl,
427 .maxlen = sizeof(int),
428 .mode = 0644,
429 .proc_handler = proc_dointvec_jiffies,
430 },
431 {
432 .procname = "inet_peer_maxttl",
433 .data = &inet_peer_maxttl,
434 .maxlen = sizeof(int),
435 .mode = 0644,
436 .proc_handler = proc_dointvec_jiffies,
437 },
438 {
439 .procname = "tcp_mem",
440 .maxlen = sizeof(sysctl_tcp_mem),
441 .data = &sysctl_tcp_mem,
442 .mode = 0644,
443 .proc_handler = proc_doulongvec_minmax,
444 },
445 {
446 .procname = "tcp_low_latency",
447 .data = &sysctl_tcp_low_latency,
448 .maxlen = sizeof(int),
449 .mode = 0644,
450 .proc_handler = proc_dointvec
451 },
452#ifdef CONFIG_NETLABEL
453 {
454 .procname = "cipso_cache_enable",
455 .data = &cipso_v4_cache_enabled,
456 .maxlen = sizeof(int),
457 .mode = 0644,
458 .proc_handler = proc_dointvec,
459 },
460 {
461 .procname = "cipso_cache_bucket_size",
462 .data = &cipso_v4_cache_bucketsize,
463 .maxlen = sizeof(int),
464 .mode = 0644,
465 .proc_handler = proc_dointvec,
466 },
467 {
468 .procname = "cipso_rbm_optfmt",
469 .data = &cipso_v4_rbm_optfmt,
470 .maxlen = sizeof(int),
471 .mode = 0644,
472 .proc_handler = proc_dointvec,
473 },
474 {
475 .procname = "cipso_rbm_strictvalid",
476 .data = &cipso_v4_rbm_strictvalid,
477 .maxlen = sizeof(int),
478 .mode = 0644,
479 .proc_handler = proc_dointvec,
480 },
481#endif /* CONFIG_NETLABEL */
482 {
483 .procname = "tcp_available_congestion_control",
484 .maxlen = TCP_CA_BUF_MAX,
485 .mode = 0444,
486 .proc_handler = proc_tcp_available_congestion_control,
487 },
488 {
489 .procname = "tcp_allowed_congestion_control",
490 .maxlen = TCP_CA_BUF_MAX,
491 .mode = 0644,
492 .proc_handler = proc_allowed_congestion_control,
493 },
494 {
495 .procname = "tcp_available_ulp",
496 .maxlen = TCP_ULP_BUF_MAX,
497 .mode = 0444,
498 .proc_handler = proc_tcp_available_ulp,
499 },
500 {
501 .procname = "icmp_msgs_per_sec",
502 .data = &sysctl_icmp_msgs_per_sec,
503 .maxlen = sizeof(int),
504 .mode = 0644,
505 .proc_handler = proc_dointvec_minmax,
506 .extra1 = &zero,
507 },
508 {
509 .procname = "icmp_msgs_burst",
510 .data = &sysctl_icmp_msgs_burst,
511 .maxlen = sizeof(int),
512 .mode = 0644,
513 .proc_handler = proc_dointvec_minmax,
514 .extra1 = &zero,
515 },
516 {
517 .procname = "udp_mem",
518 .data = &sysctl_udp_mem,
519 .maxlen = sizeof(sysctl_udp_mem),
520 .mode = 0644,
521 .proc_handler = proc_doulongvec_minmax,
522 },
523 { }
524};
525
526static struct ctl_table ipv4_net_table[] = {
527 {
528 .procname = "icmp_echo_ignore_all",
529 .data = &init_net.ipv4.sysctl_icmp_echo_ignore_all,
530 .maxlen = sizeof(int),
531 .mode = 0644,
532 .proc_handler = proc_dointvec
533 },
534 {
535 .procname = "icmp_echo_ignore_broadcasts",
536 .data = &init_net.ipv4.sysctl_icmp_echo_ignore_broadcasts,
537 .maxlen = sizeof(int),
538 .mode = 0644,
539 .proc_handler = proc_dointvec
540 },
541 {
542 .procname = "icmp_ignore_bogus_error_responses",
543 .data = &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses,
544 .maxlen = sizeof(int),
545 .mode = 0644,
546 .proc_handler = proc_dointvec
547 },
548 {
549 .procname = "icmp_errors_use_inbound_ifaddr",
550 .data = &init_net.ipv4.sysctl_icmp_errors_use_inbound_ifaddr,
551 .maxlen = sizeof(int),
552 .mode = 0644,
553 .proc_handler = proc_dointvec
554 },
555 {
556 .procname = "icmp_ratelimit",
557 .data = &init_net.ipv4.sysctl_icmp_ratelimit,
558 .maxlen = sizeof(int),
559 .mode = 0644,
560 .proc_handler = proc_dointvec_ms_jiffies,
561 },
562 {
563 .procname = "icmp_ratemask",
564 .data = &init_net.ipv4.sysctl_icmp_ratemask,
565 .maxlen = sizeof(int),
566 .mode = 0644,
567 .proc_handler = proc_dointvec
568 },
569 {
570 .procname = "ping_group_range",
571 .data = &init_net.ipv4.ping_group_range.range,
572 .maxlen = sizeof(gid_t)*2,
573 .mode = 0644,
574 .proc_handler = ipv4_ping_group_range,
575 },
576 {
577 .procname = "tcp_ecn",
578 .data = &init_net.ipv4.sysctl_tcp_ecn,
579 .maxlen = sizeof(int),
580 .mode = 0644,
581 .proc_handler = proc_dointvec
582 },
583 {
584 .procname = "tcp_ecn_fallback",
585 .data = &init_net.ipv4.sysctl_tcp_ecn_fallback,
586 .maxlen = sizeof(int),
587 .mode = 0644,
588 .proc_handler = proc_dointvec
589 },
590 {
591 .procname = "ip_dynaddr",
592 .data = &init_net.ipv4.sysctl_ip_dynaddr,
593 .maxlen = sizeof(int),
594 .mode = 0644,
595 .proc_handler = proc_dointvec
596 },
597 {
598 .procname = "ip_early_demux",
599 .data = &init_net.ipv4.sysctl_ip_early_demux,
600 .maxlen = sizeof(int),
601 .mode = 0644,
602 .proc_handler = proc_dointvec
603 },
604 {
605 .procname = "udp_early_demux",
606 .data = &init_net.ipv4.sysctl_udp_early_demux,
607 .maxlen = sizeof(int),
608 .mode = 0644,
609 .proc_handler = proc_udp_early_demux
610 },
611 {
612 .procname = "tcp_early_demux",
613 .data = &init_net.ipv4.sysctl_tcp_early_demux,
614 .maxlen = sizeof(int),
615 .mode = 0644,
616 .proc_handler = proc_tcp_early_demux
617 },
618 {
619 .procname = "ip_default_ttl",
620 .data = &init_net.ipv4.sysctl_ip_default_ttl,
621 .maxlen = sizeof(int),
622 .mode = 0644,
623 .proc_handler = proc_dointvec_minmax,
624 .extra1 = &ip_ttl_min,
625 .extra2 = &ip_ttl_max,
626 },
627 {
628 .procname = "ip_local_port_range",
629 .maxlen = sizeof(init_net.ipv4.ip_local_ports.range),
630 .data = &init_net.ipv4.ip_local_ports.range,
631 .mode = 0644,
632 .proc_handler = ipv4_local_port_range,
633 },
634 {
635 .procname = "ip_local_reserved_ports",
636 .data = &init_net.ipv4.sysctl_local_reserved_ports,
637 .maxlen = 65536,
638 .mode = 0644,
639 .proc_handler = proc_do_large_bitmap,
640 },
641 {
642 .procname = "ip_no_pmtu_disc",
643 .data = &init_net.ipv4.sysctl_ip_no_pmtu_disc,
644 .maxlen = sizeof(int),
645 .mode = 0644,
646 .proc_handler = proc_dointvec
647 },
648 {
649 .procname = "ip_forward_use_pmtu",
650 .data = &init_net.ipv4.sysctl_ip_fwd_use_pmtu,
651 .maxlen = sizeof(int),
652 .mode = 0644,
653 .proc_handler = proc_dointvec,
654 },
655 {
656 .procname = "ip_nonlocal_bind",
657 .data = &init_net.ipv4.sysctl_ip_nonlocal_bind,
658 .maxlen = sizeof(int),
659 .mode = 0644,
660 .proc_handler = proc_dointvec
661 },
662 {
663 .procname = "fwmark_reflect",
664 .data = &init_net.ipv4.sysctl_fwmark_reflect,
665 .maxlen = sizeof(int),
666 .mode = 0644,
667 .proc_handler = proc_dointvec,
668 },
669 {
670 .procname = "tcp_fwmark_accept",
671 .data = &init_net.ipv4.sysctl_tcp_fwmark_accept,
672 .maxlen = sizeof(int),
673 .mode = 0644,
674 .proc_handler = proc_dointvec,
675 },
676#ifdef CONFIG_NET_L3_MASTER_DEV
677 {
678 .procname = "tcp_l3mdev_accept",
679 .data = &init_net.ipv4.sysctl_tcp_l3mdev_accept,
680 .maxlen = sizeof(int),
681 .mode = 0644,
682 .proc_handler = proc_dointvec_minmax,
683 .extra1 = &zero,
684 .extra2 = &one,
685 },
686#endif
687 {
688 .procname = "tcp_mtu_probing",
689 .data = &init_net.ipv4.sysctl_tcp_mtu_probing,
690 .maxlen = sizeof(int),
691 .mode = 0644,
692 .proc_handler = proc_dointvec,
693 },
694 {
695 .procname = "tcp_base_mss",
696 .data = &init_net.ipv4.sysctl_tcp_base_mss,
697 .maxlen = sizeof(int),
698 .mode = 0644,
699 .proc_handler = proc_dointvec,
700 },
701 {
702 .procname = "tcp_probe_threshold",
703 .data = &init_net.ipv4.sysctl_tcp_probe_threshold,
704 .maxlen = sizeof(int),
705 .mode = 0644,
706 .proc_handler = proc_dointvec,
707 },
708 {
709 .procname = "tcp_probe_interval",
710 .data = &init_net.ipv4.sysctl_tcp_probe_interval,
711 .maxlen = sizeof(int),
712 .mode = 0644,
713 .proc_handler = proc_dointvec,
714 },
715 {
716 .procname = "igmp_link_local_mcast_reports",
717 .data = &init_net.ipv4.sysctl_igmp_llm_reports,
718 .maxlen = sizeof(int),
719 .mode = 0644,
720 .proc_handler = proc_dointvec
721 },
722 {
723 .procname = "igmp_max_memberships",
724 .data = &init_net.ipv4.sysctl_igmp_max_memberships,
725 .maxlen = sizeof(int),
726 .mode = 0644,
727 .proc_handler = proc_dointvec
728 },
729 {
730 .procname = "igmp_max_msf",
731 .data = &init_net.ipv4.sysctl_igmp_max_msf,
732 .maxlen = sizeof(int),
733 .mode = 0644,
734 .proc_handler = proc_dointvec
735 },
736#ifdef CONFIG_IP_MULTICAST
737 {
738 .procname = "igmp_qrv",
739 .data = &init_net.ipv4.sysctl_igmp_qrv,
740 .maxlen = sizeof(int),
741 .mode = 0644,
742 .proc_handler = proc_dointvec_minmax,
743 .extra1 = &one
744 },
745#endif
746 {
747 .procname = "tcp_congestion_control",
748 .data = &init_net.ipv4.tcp_congestion_control,
749 .mode = 0644,
750 .maxlen = TCP_CA_NAME_MAX,
751 .proc_handler = proc_tcp_congestion_control,
752 },
753 {
754 .procname = "tcp_keepalive_time",
755 .data = &init_net.ipv4.sysctl_tcp_keepalive_time,
756 .maxlen = sizeof(int),
757 .mode = 0644,
758 .proc_handler = proc_dointvec_jiffies,
759 },
760 {
761 .procname = "tcp_keepalive_probes",
762 .data = &init_net.ipv4.sysctl_tcp_keepalive_probes,
763 .maxlen = sizeof(int),
764 .mode = 0644,
765 .proc_handler = proc_dointvec
766 },
767 {
768 .procname = "tcp_keepalive_intvl",
769 .data = &init_net.ipv4.sysctl_tcp_keepalive_intvl,
770 .maxlen = sizeof(int),
771 .mode = 0644,
772 .proc_handler = proc_dointvec_jiffies,
773 },
774 {
775 .procname = "tcp_syn_retries",
776 .data = &init_net.ipv4.sysctl_tcp_syn_retries,
777 .maxlen = sizeof(int),
778 .mode = 0644,
779 .proc_handler = proc_dointvec_minmax,
780 .extra1 = &tcp_syn_retries_min,
781 .extra2 = &tcp_syn_retries_max
782 },
783 {
784 .procname = "tcp_synack_retries",
785 .data = &init_net.ipv4.sysctl_tcp_synack_retries,
786 .maxlen = sizeof(int),
787 .mode = 0644,
788 .proc_handler = proc_dointvec
789 },
790#ifdef CONFIG_SYN_COOKIES
791 {
792 .procname = "tcp_syncookies",
793 .data = &init_net.ipv4.sysctl_tcp_syncookies,
794 .maxlen = sizeof(int),
795 .mode = 0644,
796 .proc_handler = proc_dointvec
797 },
798#endif
799 {
800 .procname = "tcp_reordering",
801 .data = &init_net.ipv4.sysctl_tcp_reordering,
802 .maxlen = sizeof(int),
803 .mode = 0644,
804 .proc_handler = proc_dointvec
805 },
806 {
807 .procname = "tcp_retries1",
808 .data = &init_net.ipv4.sysctl_tcp_retries1,
809 .maxlen = sizeof(int),
810 .mode = 0644,
811 .proc_handler = proc_dointvec_minmax,
812 .extra2 = &tcp_retr1_max
813 },
814 {
815 .procname = "tcp_retries2",
816 .data = &init_net.ipv4.sysctl_tcp_retries2,
817 .maxlen = sizeof(int),
818 .mode = 0644,
819 .proc_handler = proc_dointvec
820 },
821 {
822 .procname = "tcp_orphan_retries",
823 .data = &init_net.ipv4.sysctl_tcp_orphan_retries,
824 .maxlen = sizeof(int),
825 .mode = 0644,
826 .proc_handler = proc_dointvec
827 },
828 {
829 .procname = "tcp_fin_timeout",
830 .data = &init_net.ipv4.sysctl_tcp_fin_timeout,
831 .maxlen = sizeof(int),
832 .mode = 0644,
833 .proc_handler = proc_dointvec_jiffies,
834 },
835 {
836 .procname = "tcp_notsent_lowat",
837 .data = &init_net.ipv4.sysctl_tcp_notsent_lowat,
838 .maxlen = sizeof(unsigned int),
839 .mode = 0644,
840 .proc_handler = proc_douintvec,
841 },
842 {
843 .procname = "tcp_tw_reuse",
844 .data = &init_net.ipv4.sysctl_tcp_tw_reuse,
845 .maxlen = sizeof(int),
846 .mode = 0644,
847 .proc_handler = proc_dointvec
848 },
849 {
850 .procname = "tcp_max_tw_buckets",
851 .data = &init_net.ipv4.tcp_death_row.sysctl_max_tw_buckets,
852 .maxlen = sizeof(int),
853 .mode = 0644,
854 .proc_handler = proc_dointvec
855 },
856 {
857 .procname = "tcp_max_syn_backlog",
858 .data = &init_net.ipv4.sysctl_max_syn_backlog,
859 .maxlen = sizeof(int),
860 .mode = 0644,
861 .proc_handler = proc_dointvec
862 },
863 {
864 .procname = "tcp_fastopen",
865 .data = &init_net.ipv4.sysctl_tcp_fastopen,
866 .maxlen = sizeof(int),
867 .mode = 0644,
868 .proc_handler = proc_dointvec,
869 },
870 {
871 .procname = "tcp_fastopen_key",
872 .mode = 0600,
873 .data = &init_net.ipv4.sysctl_tcp_fastopen,
874 .maxlen = ((TCP_FASTOPEN_KEY_LENGTH * 2) + 10),
875 .proc_handler = proc_tcp_fastopen_key,
876 },
877 {
878 .procname = "tcp_fastopen_blackhole_timeout_sec",
879 .data = &init_net.ipv4.sysctl_tcp_fastopen_blackhole_timeout,
880 .maxlen = sizeof(int),
881 .mode = 0644,
882 .proc_handler = proc_tfo_blackhole_detect_timeout,
883 .extra1 = &zero,
884 },
885#ifdef CONFIG_IP_ROUTE_MULTIPATH
886 {
887 .procname = "fib_multipath_use_neigh",
888 .data = &init_net.ipv4.sysctl_fib_multipath_use_neigh,
889 .maxlen = sizeof(int),
890 .mode = 0644,
891 .proc_handler = proc_dointvec_minmax,
892 .extra1 = &zero,
893 .extra2 = &one,
894 },
895 {
896 .procname = "fib_multipath_hash_policy",
897 .data = &init_net.ipv4.sysctl_fib_multipath_hash_policy,
898 .maxlen = sizeof(int),
899 .mode = 0644,
900 .proc_handler = proc_fib_multipath_hash_policy,
901 .extra1 = &zero,
902 .extra2 = &one,
903 },
904#endif
905 {
906 .procname = "ip_unprivileged_port_start",
907 .maxlen = sizeof(int),
908 .data = &init_net.ipv4.sysctl_ip_prot_sock,
909 .mode = 0644,
910 .proc_handler = ipv4_privileged_ports,
911 },
912#ifdef CONFIG_NET_L3_MASTER_DEV
913 {
914 .procname = "udp_l3mdev_accept",
915 .data = &init_net.ipv4.sysctl_udp_l3mdev_accept,
916 .maxlen = sizeof(int),
917 .mode = 0644,
918 .proc_handler = proc_dointvec_minmax,
919 .extra1 = &zero,
920 .extra2 = &one,
921 },
922#endif
923 {
924 .procname = "tcp_sack",
925 .data = &init_net.ipv4.sysctl_tcp_sack,
926 .maxlen = sizeof(int),
927 .mode = 0644,
928 .proc_handler = proc_dointvec
929 },
930 {
931 .procname = "tcp_window_scaling",
932 .data = &init_net.ipv4.sysctl_tcp_window_scaling,
933 .maxlen = sizeof(int),
934 .mode = 0644,
935 .proc_handler = proc_dointvec
936 },
937 {
938 .procname = "tcp_timestamps",
939 .data = &init_net.ipv4.sysctl_tcp_timestamps,
940 .maxlen = sizeof(int),
941 .mode = 0644,
942 .proc_handler = proc_dointvec
943 },
944 {
945 .procname = "tcp_early_retrans",
946 .data = &init_net.ipv4.sysctl_tcp_early_retrans,
947 .maxlen = sizeof(int),
948 .mode = 0644,
949 .proc_handler = proc_dointvec_minmax,
950 .extra1 = &zero,
951 .extra2 = &four,
952 },
953 {
954 .procname = "tcp_recovery",
955 .data = &init_net.ipv4.sysctl_tcp_recovery,
956 .maxlen = sizeof(int),
957 .mode = 0644,
958 .proc_handler = proc_dointvec,
959 },
960 {
961 .procname = "tcp_thin_linear_timeouts",
962 .data = &init_net.ipv4.sysctl_tcp_thin_linear_timeouts,
963 .maxlen = sizeof(int),
964 .mode = 0644,
965 .proc_handler = proc_dointvec
966 },
967 {
968 .procname = "tcp_slow_start_after_idle",
969 .data = &init_net.ipv4.sysctl_tcp_slow_start_after_idle,
970 .maxlen = sizeof(int),
971 .mode = 0644,
972 .proc_handler = proc_dointvec
973 },
974 {
975 .procname = "tcp_retrans_collapse",
976 .data = &init_net.ipv4.sysctl_tcp_retrans_collapse,
977 .maxlen = sizeof(int),
978 .mode = 0644,
979 .proc_handler = proc_dointvec
980 },
981 {
982 .procname = "tcp_stdurg",
983 .data = &init_net.ipv4.sysctl_tcp_stdurg,
984 .maxlen = sizeof(int),
985 .mode = 0644,
986 .proc_handler = proc_dointvec
987 },
988 {
989 .procname = "tcp_rfc1337",
990 .data = &init_net.ipv4.sysctl_tcp_rfc1337,
991 .maxlen = sizeof(int),
992 .mode = 0644,
993 .proc_handler = proc_dointvec
994 },
995 {
996 .procname = "tcp_abort_on_overflow",
997 .data = &init_net.ipv4.sysctl_tcp_abort_on_overflow,
998 .maxlen = sizeof(int),
999 .mode = 0644,
1000 .proc_handler = proc_dointvec
1001 },
1002 {
1003 .procname = "tcp_fack",
1004 .data = &init_net.ipv4.sysctl_tcp_fack,
1005 .maxlen = sizeof(int),
1006 .mode = 0644,
1007 .proc_handler = proc_dointvec
1008 },
1009 {
1010 .procname = "tcp_max_reordering",
1011 .data = &init_net.ipv4.sysctl_tcp_max_reordering,
1012 .maxlen = sizeof(int),
1013 .mode = 0644,
1014 .proc_handler = proc_dointvec
1015 },
1016 {
1017 .procname = "tcp_dsack",
1018 .data = &init_net.ipv4.sysctl_tcp_dsack,
1019 .maxlen = sizeof(int),
1020 .mode = 0644,
1021 .proc_handler = proc_dointvec
1022 },
1023 {
1024 .procname = "tcp_app_win",
1025 .data = &init_net.ipv4.sysctl_tcp_app_win,
1026 .maxlen = sizeof(int),
1027 .mode = 0644,
1028 .proc_handler = proc_dointvec
1029 },
1030 {
1031 .procname = "tcp_adv_win_scale",
1032 .data = &init_net.ipv4.sysctl_tcp_adv_win_scale,
1033 .maxlen = sizeof(int),
1034 .mode = 0644,
1035 .proc_handler = proc_dointvec_minmax,
1036 .extra1 = &tcp_adv_win_scale_min,
1037 .extra2 = &tcp_adv_win_scale_max,
1038 },
1039 {
1040 .procname = "tcp_frto",
1041 .data = &init_net.ipv4.sysctl_tcp_frto,
1042 .maxlen = sizeof(int),
1043 .mode = 0644,
1044 .proc_handler = proc_dointvec
1045 },
1046 {
1047 .procname = "tcp_no_metrics_save",
1048 .data = &init_net.ipv4.sysctl_tcp_nometrics_save,
1049 .maxlen = sizeof(int),
1050 .mode = 0644,
1051 .proc_handler = proc_dointvec,
1052 },
1053 {
1054 .procname = "tcp_moderate_rcvbuf",
1055 .data = &init_net.ipv4.sysctl_tcp_moderate_rcvbuf,
1056 .maxlen = sizeof(int),
1057 .mode = 0644,
1058 .proc_handler = proc_dointvec,
1059 },
1060 {
1061 .procname = "tcp_tso_win_divisor",
1062 .data = &init_net.ipv4.sysctl_tcp_tso_win_divisor,
1063 .maxlen = sizeof(int),
1064 .mode = 0644,
1065 .proc_handler = proc_dointvec,
1066 },
1067 {
1068 .procname = "tcp_workaround_signed_windows",
1069 .data = &init_net.ipv4.sysctl_tcp_workaround_signed_windows,
1070 .maxlen = sizeof(int),
1071 .mode = 0644,
1072 .proc_handler = proc_dointvec
1073 },
1074 {
1075 .procname = "tcp_limit_output_bytes",
1076 .data = &init_net.ipv4.sysctl_tcp_limit_output_bytes,
1077 .maxlen = sizeof(int),
1078 .mode = 0644,
1079 .proc_handler = proc_dointvec
1080 },
1081 {
1082 .procname = "tcp_challenge_ack_limit",
1083 .data = &init_net.ipv4.sysctl_tcp_challenge_ack_limit,
1084 .maxlen = sizeof(int),
1085 .mode = 0644,
1086 .proc_handler = proc_dointvec
1087 },
1088 {
1089 .procname = "tcp_min_tso_segs",
1090 .data = &init_net.ipv4.sysctl_tcp_min_tso_segs,
1091 .maxlen = sizeof(int),
1092 .mode = 0644,
1093 .proc_handler = proc_dointvec_minmax,
1094 .extra1 = &one,
1095 .extra2 = &gso_max_segs,
1096 },
1097 {
1098 .procname = "tcp_min_rtt_wlen",
1099 .data = &init_net.ipv4.sysctl_tcp_min_rtt_wlen,
1100 .maxlen = sizeof(int),
1101 .mode = 0644,
1102 .proc_handler = proc_dointvec
1103 },
1104 {
1105 .procname = "tcp_autocorking",
1106 .data = &init_net.ipv4.sysctl_tcp_autocorking,
1107 .maxlen = sizeof(int),
1108 .mode = 0644,
1109 .proc_handler = proc_dointvec_minmax,
1110 .extra1 = &zero,
1111 .extra2 = &one,
1112 },
1113 {
1114 .procname = "tcp_invalid_ratelimit",
1115 .data = &init_net.ipv4.sysctl_tcp_invalid_ratelimit,
1116 .maxlen = sizeof(int),
1117 .mode = 0644,
1118 .proc_handler = proc_dointvec_ms_jiffies,
1119 },
1120 {
1121 .procname = "tcp_pacing_ss_ratio",
1122 .data = &init_net.ipv4.sysctl_tcp_pacing_ss_ratio,
1123 .maxlen = sizeof(int),
1124 .mode = 0644,
1125 .proc_handler = proc_dointvec_minmax,
1126 .extra1 = &zero,
1127 .extra2 = &thousand,
1128 },
1129 {
1130 .procname = "tcp_pacing_ca_ratio",
1131 .data = &init_net.ipv4.sysctl_tcp_pacing_ca_ratio,
1132 .maxlen = sizeof(int),
1133 .mode = 0644,
1134 .proc_handler = proc_dointvec_minmax,
1135 .extra1 = &zero,
1136 .extra2 = &thousand,
1137 },
1138 {
1139 .procname = "tcp_wmem",
1140 .data = &init_net.ipv4.sysctl_tcp_wmem,
1141 .maxlen = sizeof(init_net.ipv4.sysctl_tcp_wmem),
1142 .mode = 0644,
1143 .proc_handler = proc_dointvec_minmax,
1144 .extra1 = &one,
1145 },
1146 {
1147 .procname = "tcp_rmem",
1148 .data = &init_net.ipv4.sysctl_tcp_rmem,
1149 .maxlen = sizeof(init_net.ipv4.sysctl_tcp_rmem),
1150 .mode = 0644,
1151 .proc_handler = proc_dointvec_minmax,
1152 .extra1 = &one,
1153 },
1154 {
1155 .procname = "udp_rmem_min",
1156 .data = &init_net.ipv4.sysctl_udp_rmem_min,
1157 .maxlen = sizeof(init_net.ipv4.sysctl_udp_rmem_min),
1158 .mode = 0644,
1159 .proc_handler = proc_dointvec_minmax,
1160 .extra1 = &one
1161 },
1162 {
1163 .procname = "udp_wmem_min",
1164 .data = &init_net.ipv4.sysctl_udp_wmem_min,
1165 .maxlen = sizeof(init_net.ipv4.sysctl_udp_wmem_min),
1166 .mode = 0644,
1167 .proc_handler = proc_dointvec_minmax,
1168 .extra1 = &one
1169 },
1170 { }
1171};
1172
1173static __net_init int ipv4_sysctl_init_net(struct net *net)
1174{
1175 struct ctl_table *table;
1176
1177 table = ipv4_net_table;
1178 if (!net_eq(net, &init_net)) {
1179 int i;
1180
1181 table = kmemdup(table, sizeof(ipv4_net_table), GFP_KERNEL);
1182 if (!table)
1183 goto err_alloc;
1184
1185 /* Update the variables to point into the current struct net */
1186 for (i = 0; i < ARRAY_SIZE(ipv4_net_table) - 1; i++)
1187 table[i].data += (void *)net - (void *)&init_net;
1188 }
1189
1190 net->ipv4.ipv4_hdr = register_net_sysctl(net, "net/ipv4", table);
1191 if (!net->ipv4.ipv4_hdr)
1192 goto err_reg;
1193
1194 net->ipv4.sysctl_local_reserved_ports = kzalloc(65536 / 8, GFP_KERNEL);
1195 if (!net->ipv4.sysctl_local_reserved_ports)
1196 goto err_ports;
1197
1198 return 0;
1199
1200err_ports:
1201 unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
1202err_reg:
1203 if (!net_eq(net, &init_net))
1204 kfree(table);
1205err_alloc:
1206 return -ENOMEM;
1207}
1208
1209static __net_exit void ipv4_sysctl_exit_net(struct net *net)
1210{
1211 struct ctl_table *table;
1212
1213 kfree(net->ipv4.sysctl_local_reserved_ports);
1214 table = net->ipv4.ipv4_hdr->ctl_table_arg;
1215 unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
1216 kfree(table);
1217}
1218
1219static __net_initdata struct pernet_operations ipv4_sysctl_ops = {
1220 .init = ipv4_sysctl_init_net,
1221 .exit = ipv4_sysctl_exit_net,
1222};
1223
1224static __init int sysctl_ipv4_init(void)
1225{
1226 struct ctl_table_header *hdr;
1227
1228 hdr = register_net_sysctl(&init_net, "net/ipv4", ipv4_table);
1229 if (!hdr)
1230 return -ENOMEM;
1231
1232 if (register_pernet_subsys(&ipv4_sysctl_ops)) {
1233 unregister_net_sysctl_table(hdr);
1234 return -ENOMEM;
1235 }
1236
1237 return 0;
1238}
1239
1240__initcall(sysctl_ipv4_init);
1/*
2 * sysctl_net_ipv4.c: sysctl interface to net IPV4 subsystem.
3 *
4 * Begun April 1, 1996, Mike Shaver.
5 * Added /proc/sys/net/ipv4 directory entry (empty =) ). [MS]
6 */
7
8#include <linux/mm.h>
9#include <linux/module.h>
10#include <linux/sysctl.h>
11#include <linux/igmp.h>
12#include <linux/inetdevice.h>
13#include <linux/seqlock.h>
14#include <linux/init.h>
15#include <linux/slab.h>
16#include <linux/nsproxy.h>
17#include <linux/swap.h>
18#include <net/snmp.h>
19#include <net/icmp.h>
20#include <net/ip.h>
21#include <net/route.h>
22#include <net/tcp.h>
23#include <net/udp.h>
24#include <net/cipso_ipv4.h>
25#include <net/inet_frag.h>
26#include <net/ping.h>
27#include <net/tcp_memcontrol.h>
28
29static int zero;
30static int two = 2;
31static int tcp_retr1_max = 255;
32static int ip_local_port_range_min[] = { 1, 1 };
33static int ip_local_port_range_max[] = { 65535, 65535 };
34static int tcp_adv_win_scale_min = -31;
35static int tcp_adv_win_scale_max = 31;
36static int ip_ttl_min = 1;
37static int ip_ttl_max = 255;
38static int ip_ping_group_range_min[] = { 0, 0 };
39static int ip_ping_group_range_max[] = { GID_T_MAX, GID_T_MAX };
40
41/* Update system visible IP port range */
42static void set_local_port_range(int range[2])
43{
44 write_seqlock(&sysctl_local_ports.lock);
45 sysctl_local_ports.range[0] = range[0];
46 sysctl_local_ports.range[1] = range[1];
47 write_sequnlock(&sysctl_local_ports.lock);
48}
49
50/* Validate changes from /proc interface. */
51static int ipv4_local_port_range(ctl_table *table, int write,
52 void __user *buffer,
53 size_t *lenp, loff_t *ppos)
54{
55 int ret;
56 int range[2];
57 ctl_table tmp = {
58 .data = &range,
59 .maxlen = sizeof(range),
60 .mode = table->mode,
61 .extra1 = &ip_local_port_range_min,
62 .extra2 = &ip_local_port_range_max,
63 };
64
65 inet_get_local_port_range(range, range + 1);
66 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
67
68 if (write && ret == 0) {
69 if (range[1] < range[0])
70 ret = -EINVAL;
71 else
72 set_local_port_range(range);
73 }
74
75 return ret;
76}
77
78
79static void inet_get_ping_group_range_table(struct ctl_table *table, gid_t *low, gid_t *high)
80{
81 gid_t *data = table->data;
82 unsigned int seq;
83 do {
84 seq = read_seqbegin(&sysctl_local_ports.lock);
85
86 *low = data[0];
87 *high = data[1];
88 } while (read_seqretry(&sysctl_local_ports.lock, seq));
89}
90
91/* Update system visible IP port range */
92static void set_ping_group_range(struct ctl_table *table, gid_t range[2])
93{
94 gid_t *data = table->data;
95 write_seqlock(&sysctl_local_ports.lock);
96 data[0] = range[0];
97 data[1] = range[1];
98 write_sequnlock(&sysctl_local_ports.lock);
99}
100
101/* Validate changes from /proc interface. */
102static int ipv4_ping_group_range(ctl_table *table, int write,
103 void __user *buffer,
104 size_t *lenp, loff_t *ppos)
105{
106 int ret;
107 gid_t range[2];
108 ctl_table tmp = {
109 .data = &range,
110 .maxlen = sizeof(range),
111 .mode = table->mode,
112 .extra1 = &ip_ping_group_range_min,
113 .extra2 = &ip_ping_group_range_max,
114 };
115
116 inet_get_ping_group_range_table(table, range, range + 1);
117 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
118
119 if (write && ret == 0)
120 set_ping_group_range(table, range);
121
122 return ret;
123}
124
125static int proc_tcp_congestion_control(ctl_table *ctl, int write,
126 void __user *buffer, size_t *lenp, loff_t *ppos)
127{
128 char val[TCP_CA_NAME_MAX];
129 ctl_table tbl = {
130 .data = val,
131 .maxlen = TCP_CA_NAME_MAX,
132 };
133 int ret;
134
135 tcp_get_default_congestion_control(val);
136
137 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
138 if (write && ret == 0)
139 ret = tcp_set_default_congestion_control(val);
140 return ret;
141}
142
143static int proc_tcp_available_congestion_control(ctl_table *ctl,
144 int write,
145 void __user *buffer, size_t *lenp,
146 loff_t *ppos)
147{
148 ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX, };
149 int ret;
150
151 tbl.data = kmalloc(tbl.maxlen, GFP_USER);
152 if (!tbl.data)
153 return -ENOMEM;
154 tcp_get_available_congestion_control(tbl.data, TCP_CA_BUF_MAX);
155 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
156 kfree(tbl.data);
157 return ret;
158}
159
160static int proc_allowed_congestion_control(ctl_table *ctl,
161 int write,
162 void __user *buffer, size_t *lenp,
163 loff_t *ppos)
164{
165 ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX };
166 int ret;
167
168 tbl.data = kmalloc(tbl.maxlen, GFP_USER);
169 if (!tbl.data)
170 return -ENOMEM;
171
172 tcp_get_allowed_congestion_control(tbl.data, tbl.maxlen);
173 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
174 if (write && ret == 0)
175 ret = tcp_set_allowed_congestion_control(tbl.data);
176 kfree(tbl.data);
177 return ret;
178}
179
180static int ipv4_tcp_mem(ctl_table *ctl, int write,
181 void __user *buffer, size_t *lenp,
182 loff_t *ppos)
183{
184 int ret;
185 unsigned long vec[3];
186 struct net *net = current->nsproxy->net_ns;
187#ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM
188 struct mem_cgroup *memcg;
189#endif
190
191 ctl_table tmp = {
192 .data = &vec,
193 .maxlen = sizeof(vec),
194 .mode = ctl->mode,
195 };
196
197 if (!write) {
198 ctl->data = &net->ipv4.sysctl_tcp_mem;
199 return proc_doulongvec_minmax(ctl, write, buffer, lenp, ppos);
200 }
201
202 ret = proc_doulongvec_minmax(&tmp, write, buffer, lenp, ppos);
203 if (ret)
204 return ret;
205
206#ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM
207 rcu_read_lock();
208 memcg = mem_cgroup_from_task(current);
209
210 tcp_prot_mem(memcg, vec[0], 0);
211 tcp_prot_mem(memcg, vec[1], 1);
212 tcp_prot_mem(memcg, vec[2], 2);
213 rcu_read_unlock();
214#endif
215
216 net->ipv4.sysctl_tcp_mem[0] = vec[0];
217 net->ipv4.sysctl_tcp_mem[1] = vec[1];
218 net->ipv4.sysctl_tcp_mem[2] = vec[2];
219
220 return 0;
221}
222
223static struct ctl_table ipv4_table[] = {
224 {
225 .procname = "tcp_timestamps",
226 .data = &sysctl_tcp_timestamps,
227 .maxlen = sizeof(int),
228 .mode = 0644,
229 .proc_handler = proc_dointvec
230 },
231 {
232 .procname = "tcp_window_scaling",
233 .data = &sysctl_tcp_window_scaling,
234 .maxlen = sizeof(int),
235 .mode = 0644,
236 .proc_handler = proc_dointvec
237 },
238 {
239 .procname = "tcp_sack",
240 .data = &sysctl_tcp_sack,
241 .maxlen = sizeof(int),
242 .mode = 0644,
243 .proc_handler = proc_dointvec
244 },
245 {
246 .procname = "tcp_retrans_collapse",
247 .data = &sysctl_tcp_retrans_collapse,
248 .maxlen = sizeof(int),
249 .mode = 0644,
250 .proc_handler = proc_dointvec
251 },
252 {
253 .procname = "ip_default_ttl",
254 .data = &sysctl_ip_default_ttl,
255 .maxlen = sizeof(int),
256 .mode = 0644,
257 .proc_handler = proc_dointvec_minmax,
258 .extra1 = &ip_ttl_min,
259 .extra2 = &ip_ttl_max,
260 },
261 {
262 .procname = "ip_no_pmtu_disc",
263 .data = &ipv4_config.no_pmtu_disc,
264 .maxlen = sizeof(int),
265 .mode = 0644,
266 .proc_handler = proc_dointvec
267 },
268 {
269 .procname = "ip_nonlocal_bind",
270 .data = &sysctl_ip_nonlocal_bind,
271 .maxlen = sizeof(int),
272 .mode = 0644,
273 .proc_handler = proc_dointvec
274 },
275 {
276 .procname = "tcp_syn_retries",
277 .data = &sysctl_tcp_syn_retries,
278 .maxlen = sizeof(int),
279 .mode = 0644,
280 .proc_handler = proc_dointvec
281 },
282 {
283 .procname = "tcp_synack_retries",
284 .data = &sysctl_tcp_synack_retries,
285 .maxlen = sizeof(int),
286 .mode = 0644,
287 .proc_handler = proc_dointvec
288 },
289 {
290 .procname = "tcp_max_orphans",
291 .data = &sysctl_tcp_max_orphans,
292 .maxlen = sizeof(int),
293 .mode = 0644,
294 .proc_handler = proc_dointvec
295 },
296 {
297 .procname = "tcp_max_tw_buckets",
298 .data = &tcp_death_row.sysctl_max_tw_buckets,
299 .maxlen = sizeof(int),
300 .mode = 0644,
301 .proc_handler = proc_dointvec
302 },
303 {
304 .procname = "ip_dynaddr",
305 .data = &sysctl_ip_dynaddr,
306 .maxlen = sizeof(int),
307 .mode = 0644,
308 .proc_handler = proc_dointvec
309 },
310 {
311 .procname = "tcp_keepalive_time",
312 .data = &sysctl_tcp_keepalive_time,
313 .maxlen = sizeof(int),
314 .mode = 0644,
315 .proc_handler = proc_dointvec_jiffies,
316 },
317 {
318 .procname = "tcp_keepalive_probes",
319 .data = &sysctl_tcp_keepalive_probes,
320 .maxlen = sizeof(int),
321 .mode = 0644,
322 .proc_handler = proc_dointvec
323 },
324 {
325 .procname = "tcp_keepalive_intvl",
326 .data = &sysctl_tcp_keepalive_intvl,
327 .maxlen = sizeof(int),
328 .mode = 0644,
329 .proc_handler = proc_dointvec_jiffies,
330 },
331 {
332 .procname = "tcp_retries1",
333 .data = &sysctl_tcp_retries1,
334 .maxlen = sizeof(int),
335 .mode = 0644,
336 .proc_handler = proc_dointvec_minmax,
337 .extra2 = &tcp_retr1_max
338 },
339 {
340 .procname = "tcp_retries2",
341 .data = &sysctl_tcp_retries2,
342 .maxlen = sizeof(int),
343 .mode = 0644,
344 .proc_handler = proc_dointvec
345 },
346 {
347 .procname = "tcp_fin_timeout",
348 .data = &sysctl_tcp_fin_timeout,
349 .maxlen = sizeof(int),
350 .mode = 0644,
351 .proc_handler = proc_dointvec_jiffies,
352 },
353#ifdef CONFIG_SYN_COOKIES
354 {
355 .procname = "tcp_syncookies",
356 .data = &sysctl_tcp_syncookies,
357 .maxlen = sizeof(int),
358 .mode = 0644,
359 .proc_handler = proc_dointvec
360 },
361#endif
362 {
363 .procname = "tcp_tw_recycle",
364 .data = &tcp_death_row.sysctl_tw_recycle,
365 .maxlen = sizeof(int),
366 .mode = 0644,
367 .proc_handler = proc_dointvec
368 },
369 {
370 .procname = "tcp_abort_on_overflow",
371 .data = &sysctl_tcp_abort_on_overflow,
372 .maxlen = sizeof(int),
373 .mode = 0644,
374 .proc_handler = proc_dointvec
375 },
376 {
377 .procname = "tcp_stdurg",
378 .data = &sysctl_tcp_stdurg,
379 .maxlen = sizeof(int),
380 .mode = 0644,
381 .proc_handler = proc_dointvec
382 },
383 {
384 .procname = "tcp_rfc1337",
385 .data = &sysctl_tcp_rfc1337,
386 .maxlen = sizeof(int),
387 .mode = 0644,
388 .proc_handler = proc_dointvec
389 },
390 {
391 .procname = "tcp_max_syn_backlog",
392 .data = &sysctl_max_syn_backlog,
393 .maxlen = sizeof(int),
394 .mode = 0644,
395 .proc_handler = proc_dointvec
396 },
397 {
398 .procname = "ip_local_port_range",
399 .data = &sysctl_local_ports.range,
400 .maxlen = sizeof(sysctl_local_ports.range),
401 .mode = 0644,
402 .proc_handler = ipv4_local_port_range,
403 },
404 {
405 .procname = "ip_local_reserved_ports",
406 .data = NULL, /* initialized in sysctl_ipv4_init */
407 .maxlen = 65536,
408 .mode = 0644,
409 .proc_handler = proc_do_large_bitmap,
410 },
411 {
412 .procname = "igmp_max_memberships",
413 .data = &sysctl_igmp_max_memberships,
414 .maxlen = sizeof(int),
415 .mode = 0644,
416 .proc_handler = proc_dointvec
417 },
418 {
419 .procname = "igmp_max_msf",
420 .data = &sysctl_igmp_max_msf,
421 .maxlen = sizeof(int),
422 .mode = 0644,
423 .proc_handler = proc_dointvec
424 },
425 {
426 .procname = "inet_peer_threshold",
427 .data = &inet_peer_threshold,
428 .maxlen = sizeof(int),
429 .mode = 0644,
430 .proc_handler = proc_dointvec
431 },
432 {
433 .procname = "inet_peer_minttl",
434 .data = &inet_peer_minttl,
435 .maxlen = sizeof(int),
436 .mode = 0644,
437 .proc_handler = proc_dointvec_jiffies,
438 },
439 {
440 .procname = "inet_peer_maxttl",
441 .data = &inet_peer_maxttl,
442 .maxlen = sizeof(int),
443 .mode = 0644,
444 .proc_handler = proc_dointvec_jiffies,
445 },
446 {
447 .procname = "tcp_orphan_retries",
448 .data = &sysctl_tcp_orphan_retries,
449 .maxlen = sizeof(int),
450 .mode = 0644,
451 .proc_handler = proc_dointvec
452 },
453 {
454 .procname = "tcp_fack",
455 .data = &sysctl_tcp_fack,
456 .maxlen = sizeof(int),
457 .mode = 0644,
458 .proc_handler = proc_dointvec
459 },
460 {
461 .procname = "tcp_reordering",
462 .data = &sysctl_tcp_reordering,
463 .maxlen = sizeof(int),
464 .mode = 0644,
465 .proc_handler = proc_dointvec
466 },
467 {
468 .procname = "tcp_ecn",
469 .data = &sysctl_tcp_ecn,
470 .maxlen = sizeof(int),
471 .mode = 0644,
472 .proc_handler = proc_dointvec
473 },
474 {
475 .procname = "tcp_dsack",
476 .data = &sysctl_tcp_dsack,
477 .maxlen = sizeof(int),
478 .mode = 0644,
479 .proc_handler = proc_dointvec
480 },
481 {
482 .procname = "tcp_wmem",
483 .data = &sysctl_tcp_wmem,
484 .maxlen = sizeof(sysctl_tcp_wmem),
485 .mode = 0644,
486 .proc_handler = proc_dointvec
487 },
488 {
489 .procname = "tcp_rmem",
490 .data = &sysctl_tcp_rmem,
491 .maxlen = sizeof(sysctl_tcp_rmem),
492 .mode = 0644,
493 .proc_handler = proc_dointvec
494 },
495 {
496 .procname = "tcp_app_win",
497 .data = &sysctl_tcp_app_win,
498 .maxlen = sizeof(int),
499 .mode = 0644,
500 .proc_handler = proc_dointvec
501 },
502 {
503 .procname = "tcp_adv_win_scale",
504 .data = &sysctl_tcp_adv_win_scale,
505 .maxlen = sizeof(int),
506 .mode = 0644,
507 .proc_handler = proc_dointvec_minmax,
508 .extra1 = &tcp_adv_win_scale_min,
509 .extra2 = &tcp_adv_win_scale_max,
510 },
511 {
512 .procname = "tcp_tw_reuse",
513 .data = &sysctl_tcp_tw_reuse,
514 .maxlen = sizeof(int),
515 .mode = 0644,
516 .proc_handler = proc_dointvec
517 },
518 {
519 .procname = "tcp_frto",
520 .data = &sysctl_tcp_frto,
521 .maxlen = sizeof(int),
522 .mode = 0644,
523 .proc_handler = proc_dointvec
524 },
525 {
526 .procname = "tcp_frto_response",
527 .data = &sysctl_tcp_frto_response,
528 .maxlen = sizeof(int),
529 .mode = 0644,
530 .proc_handler = proc_dointvec
531 },
532 {
533 .procname = "tcp_low_latency",
534 .data = &sysctl_tcp_low_latency,
535 .maxlen = sizeof(int),
536 .mode = 0644,
537 .proc_handler = proc_dointvec
538 },
539 {
540 .procname = "tcp_no_metrics_save",
541 .data = &sysctl_tcp_nometrics_save,
542 .maxlen = sizeof(int),
543 .mode = 0644,
544 .proc_handler = proc_dointvec,
545 },
546 {
547 .procname = "tcp_moderate_rcvbuf",
548 .data = &sysctl_tcp_moderate_rcvbuf,
549 .maxlen = sizeof(int),
550 .mode = 0644,
551 .proc_handler = proc_dointvec,
552 },
553 {
554 .procname = "tcp_tso_win_divisor",
555 .data = &sysctl_tcp_tso_win_divisor,
556 .maxlen = sizeof(int),
557 .mode = 0644,
558 .proc_handler = proc_dointvec,
559 },
560 {
561 .procname = "tcp_congestion_control",
562 .mode = 0644,
563 .maxlen = TCP_CA_NAME_MAX,
564 .proc_handler = proc_tcp_congestion_control,
565 },
566 {
567 .procname = "tcp_abc",
568 .data = &sysctl_tcp_abc,
569 .maxlen = sizeof(int),
570 .mode = 0644,
571 .proc_handler = proc_dointvec,
572 },
573 {
574 .procname = "tcp_mtu_probing",
575 .data = &sysctl_tcp_mtu_probing,
576 .maxlen = sizeof(int),
577 .mode = 0644,
578 .proc_handler = proc_dointvec,
579 },
580 {
581 .procname = "tcp_base_mss",
582 .data = &sysctl_tcp_base_mss,
583 .maxlen = sizeof(int),
584 .mode = 0644,
585 .proc_handler = proc_dointvec,
586 },
587 {
588 .procname = "tcp_workaround_signed_windows",
589 .data = &sysctl_tcp_workaround_signed_windows,
590 .maxlen = sizeof(int),
591 .mode = 0644,
592 .proc_handler = proc_dointvec
593 },
594#ifdef CONFIG_NET_DMA
595 {
596 .procname = "tcp_dma_copybreak",
597 .data = &sysctl_tcp_dma_copybreak,
598 .maxlen = sizeof(int),
599 .mode = 0644,
600 .proc_handler = proc_dointvec
601 },
602#endif
603 {
604 .procname = "tcp_slow_start_after_idle",
605 .data = &sysctl_tcp_slow_start_after_idle,
606 .maxlen = sizeof(int),
607 .mode = 0644,
608 .proc_handler = proc_dointvec
609 },
610#ifdef CONFIG_NETLABEL
611 {
612 .procname = "cipso_cache_enable",
613 .data = &cipso_v4_cache_enabled,
614 .maxlen = sizeof(int),
615 .mode = 0644,
616 .proc_handler = proc_dointvec,
617 },
618 {
619 .procname = "cipso_cache_bucket_size",
620 .data = &cipso_v4_cache_bucketsize,
621 .maxlen = sizeof(int),
622 .mode = 0644,
623 .proc_handler = proc_dointvec,
624 },
625 {
626 .procname = "cipso_rbm_optfmt",
627 .data = &cipso_v4_rbm_optfmt,
628 .maxlen = sizeof(int),
629 .mode = 0644,
630 .proc_handler = proc_dointvec,
631 },
632 {
633 .procname = "cipso_rbm_strictvalid",
634 .data = &cipso_v4_rbm_strictvalid,
635 .maxlen = sizeof(int),
636 .mode = 0644,
637 .proc_handler = proc_dointvec,
638 },
639#endif /* CONFIG_NETLABEL */
640 {
641 .procname = "tcp_available_congestion_control",
642 .maxlen = TCP_CA_BUF_MAX,
643 .mode = 0444,
644 .proc_handler = proc_tcp_available_congestion_control,
645 },
646 {
647 .procname = "tcp_allowed_congestion_control",
648 .maxlen = TCP_CA_BUF_MAX,
649 .mode = 0644,
650 .proc_handler = proc_allowed_congestion_control,
651 },
652 {
653 .procname = "tcp_max_ssthresh",
654 .data = &sysctl_tcp_max_ssthresh,
655 .maxlen = sizeof(int),
656 .mode = 0644,
657 .proc_handler = proc_dointvec,
658 },
659 {
660 .procname = "tcp_cookie_size",
661 .data = &sysctl_tcp_cookie_size,
662 .maxlen = sizeof(int),
663 .mode = 0644,
664 .proc_handler = proc_dointvec
665 },
666 {
667 .procname = "tcp_thin_linear_timeouts",
668 .data = &sysctl_tcp_thin_linear_timeouts,
669 .maxlen = sizeof(int),
670 .mode = 0644,
671 .proc_handler = proc_dointvec
672 },
673 {
674 .procname = "tcp_thin_dupack",
675 .data = &sysctl_tcp_thin_dupack,
676 .maxlen = sizeof(int),
677 .mode = 0644,
678 .proc_handler = proc_dointvec
679 },
680 {
681 .procname = "tcp_early_retrans",
682 .data = &sysctl_tcp_early_retrans,
683 .maxlen = sizeof(int),
684 .mode = 0644,
685 .proc_handler = proc_dointvec_minmax,
686 .extra1 = &zero,
687 .extra2 = &two,
688 },
689 {
690 .procname = "udp_mem",
691 .data = &sysctl_udp_mem,
692 .maxlen = sizeof(sysctl_udp_mem),
693 .mode = 0644,
694 .proc_handler = proc_doulongvec_minmax,
695 },
696 {
697 .procname = "udp_rmem_min",
698 .data = &sysctl_udp_rmem_min,
699 .maxlen = sizeof(sysctl_udp_rmem_min),
700 .mode = 0644,
701 .proc_handler = proc_dointvec_minmax,
702 .extra1 = &zero
703 },
704 {
705 .procname = "udp_wmem_min",
706 .data = &sysctl_udp_wmem_min,
707 .maxlen = sizeof(sysctl_udp_wmem_min),
708 .mode = 0644,
709 .proc_handler = proc_dointvec_minmax,
710 .extra1 = &zero
711 },
712 { }
713};
714
715static struct ctl_table ipv4_net_table[] = {
716 {
717 .procname = "icmp_echo_ignore_all",
718 .data = &init_net.ipv4.sysctl_icmp_echo_ignore_all,
719 .maxlen = sizeof(int),
720 .mode = 0644,
721 .proc_handler = proc_dointvec
722 },
723 {
724 .procname = "icmp_echo_ignore_broadcasts",
725 .data = &init_net.ipv4.sysctl_icmp_echo_ignore_broadcasts,
726 .maxlen = sizeof(int),
727 .mode = 0644,
728 .proc_handler = proc_dointvec
729 },
730 {
731 .procname = "icmp_ignore_bogus_error_responses",
732 .data = &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses,
733 .maxlen = sizeof(int),
734 .mode = 0644,
735 .proc_handler = proc_dointvec
736 },
737 {
738 .procname = "icmp_errors_use_inbound_ifaddr",
739 .data = &init_net.ipv4.sysctl_icmp_errors_use_inbound_ifaddr,
740 .maxlen = sizeof(int),
741 .mode = 0644,
742 .proc_handler = proc_dointvec
743 },
744 {
745 .procname = "icmp_ratelimit",
746 .data = &init_net.ipv4.sysctl_icmp_ratelimit,
747 .maxlen = sizeof(int),
748 .mode = 0644,
749 .proc_handler = proc_dointvec_ms_jiffies,
750 },
751 {
752 .procname = "icmp_ratemask",
753 .data = &init_net.ipv4.sysctl_icmp_ratemask,
754 .maxlen = sizeof(int),
755 .mode = 0644,
756 .proc_handler = proc_dointvec
757 },
758 {
759 .procname = "rt_cache_rebuild_count",
760 .data = &init_net.ipv4.sysctl_rt_cache_rebuild_count,
761 .maxlen = sizeof(int),
762 .mode = 0644,
763 .proc_handler = proc_dointvec
764 },
765 {
766 .procname = "ping_group_range",
767 .data = &init_net.ipv4.sysctl_ping_group_range,
768 .maxlen = sizeof(init_net.ipv4.sysctl_ping_group_range),
769 .mode = 0644,
770 .proc_handler = ipv4_ping_group_range,
771 },
772 {
773 .procname = "tcp_mem",
774 .maxlen = sizeof(init_net.ipv4.sysctl_tcp_mem),
775 .mode = 0644,
776 .proc_handler = ipv4_tcp_mem,
777 },
778 { }
779};
780
781static __net_init int ipv4_sysctl_init_net(struct net *net)
782{
783 struct ctl_table *table;
784
785 table = ipv4_net_table;
786 if (!net_eq(net, &init_net)) {
787 table = kmemdup(table, sizeof(ipv4_net_table), GFP_KERNEL);
788 if (table == NULL)
789 goto err_alloc;
790
791 table[0].data =
792 &net->ipv4.sysctl_icmp_echo_ignore_all;
793 table[1].data =
794 &net->ipv4.sysctl_icmp_echo_ignore_broadcasts;
795 table[2].data =
796 &net->ipv4.sysctl_icmp_ignore_bogus_error_responses;
797 table[3].data =
798 &net->ipv4.sysctl_icmp_errors_use_inbound_ifaddr;
799 table[4].data =
800 &net->ipv4.sysctl_icmp_ratelimit;
801 table[5].data =
802 &net->ipv4.sysctl_icmp_ratemask;
803 table[6].data =
804 &net->ipv4.sysctl_rt_cache_rebuild_count;
805 table[7].data =
806 &net->ipv4.sysctl_ping_group_range;
807
808 }
809
810 /*
811 * Sane defaults - nobody may create ping sockets.
812 * Boot scripts should set this to distro-specific group.
813 */
814 net->ipv4.sysctl_ping_group_range[0] = 1;
815 net->ipv4.sysctl_ping_group_range[1] = 0;
816
817 net->ipv4.sysctl_rt_cache_rebuild_count = 4;
818
819 tcp_init_mem(net);
820
821 net->ipv4.ipv4_hdr = register_net_sysctl(net, "net/ipv4", table);
822 if (net->ipv4.ipv4_hdr == NULL)
823 goto err_reg;
824
825 return 0;
826
827err_reg:
828 if (!net_eq(net, &init_net))
829 kfree(table);
830err_alloc:
831 return -ENOMEM;
832}
833
834static __net_exit void ipv4_sysctl_exit_net(struct net *net)
835{
836 struct ctl_table *table;
837
838 table = net->ipv4.ipv4_hdr->ctl_table_arg;
839 unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
840 kfree(table);
841}
842
843static __net_initdata struct pernet_operations ipv4_sysctl_ops = {
844 .init = ipv4_sysctl_init_net,
845 .exit = ipv4_sysctl_exit_net,
846};
847
848static __init int sysctl_ipv4_init(void)
849{
850 struct ctl_table_header *hdr;
851 struct ctl_table *i;
852
853 for (i = ipv4_table; i->procname; i++) {
854 if (strcmp(i->procname, "ip_local_reserved_ports") == 0) {
855 i->data = sysctl_local_reserved_ports;
856 break;
857 }
858 }
859 if (!i->procname)
860 return -EINVAL;
861
862 hdr = register_net_sysctl(&init_net, "net/ipv4", ipv4_table);
863 if (hdr == NULL)
864 return -ENOMEM;
865
866 if (register_pernet_subsys(&ipv4_sysctl_ops)) {
867 unregister_net_sysctl_table(hdr);
868 return -ENOMEM;
869 }
870
871 return 0;
872}
873
874__initcall(sysctl_ipv4_init);