xref: /linux/net/sctp/sysctl.c (revision 7110f24f9e33979fd704f7a4a595a9d3e9bdacb7)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* SCTP kernel implementation
3  * (C) Copyright IBM Corp. 2002, 2004
4  * Copyright (c) 2002 Intel Corp.
5  *
6  * This file is part of the SCTP kernel implementation
7  *
8  * Sysctl related interfaces for SCTP.
9  *
10  * Please send any bug reports or fixes you make to the
11  * email address(es):
12  *    lksctp developers <linux-sctp@vger.kernel.org>
13  *
14  * Written or modified by:
15  *    Mingqin Liu           <liuming@us.ibm.com>
16  *    Jon Grimm             <jgrimm@us.ibm.com>
17  *    Ardelle Fan           <ardelle.fan@intel.com>
18  *    Ryan Layer            <rmlayer@us.ibm.com>
19  *    Sridhar Samudrala     <sri@us.ibm.com>
20  */
21 
22 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
23 
24 #include <net/sctp/structs.h>
25 #include <net/sctp/sctp.h>
26 #include <linux/sysctl.h>
27 
28 static int timer_max = 86400000; /* ms in one day */
29 static int sack_timer_min = 1;
30 static int sack_timer_max = 500;
31 static int addr_scope_max = SCTP_SCOPE_POLICY_MAX;
32 static int rwnd_scale_max = 16;
33 static int rto_alpha_min = 0;
34 static int rto_beta_min = 0;
35 static int rto_alpha_max = 1000;
36 static int rto_beta_max = 1000;
37 static int pf_expose_max = SCTP_PF_EXPOSE_MAX;
38 static int ps_retrans_max = SCTP_PS_RETRANS_MAX;
39 static int udp_port_max = 65535;
40 
41 static unsigned long max_autoclose_min = 0;
42 static unsigned long max_autoclose_max =
43 	(MAX_SCHEDULE_TIMEOUT / HZ > UINT_MAX)
44 	? UINT_MAX : MAX_SCHEDULE_TIMEOUT / HZ;
45 
46 static int proc_sctp_do_hmac_alg(const struct ctl_table *ctl, int write,
47 				 void *buffer, size_t *lenp, loff_t *ppos);
48 static int proc_sctp_do_rto_min(const struct ctl_table *ctl, int write,
49 				void *buffer, size_t *lenp, loff_t *ppos);
50 static int proc_sctp_do_rto_max(const struct ctl_table *ctl, int write, void *buffer,
51 				size_t *lenp, loff_t *ppos);
52 static int proc_sctp_do_udp_port(const struct ctl_table *ctl, int write, void *buffer,
53 				 size_t *lenp, loff_t *ppos);
54 static int proc_sctp_do_alpha_beta(const struct ctl_table *ctl, int write,
55 				   void *buffer, size_t *lenp, loff_t *ppos);
56 static int proc_sctp_do_auth(const struct ctl_table *ctl, int write,
57 			     void *buffer, size_t *lenp, loff_t *ppos);
58 static int proc_sctp_do_probe_interval(const struct ctl_table *ctl, int write,
59 				       void *buffer, size_t *lenp, loff_t *ppos);
60 
61 static struct ctl_table sctp_table[] = {
62 	{
63 		.procname	= "sctp_mem",
64 		.data		= &sysctl_sctp_mem,
65 		.maxlen		= sizeof(sysctl_sctp_mem),
66 		.mode		= 0644,
67 		.proc_handler	= proc_doulongvec_minmax
68 	},
69 	{
70 		.procname	= "sctp_rmem",
71 		.data		= &sysctl_sctp_rmem,
72 		.maxlen		= sizeof(sysctl_sctp_rmem),
73 		.mode		= 0644,
74 		.proc_handler	= proc_dointvec,
75 	},
76 	{
77 		.procname	= "sctp_wmem",
78 		.data		= &sysctl_sctp_wmem,
79 		.maxlen		= sizeof(sysctl_sctp_wmem),
80 		.mode		= 0644,
81 		.proc_handler	= proc_dointvec,
82 	},
83 };
84 
85 /* The following index defines are used in sctp_sysctl_net_register().
86  * If you add new items to the sctp_net_table, please ensure that
87  * the index values of these defines hold the same meaning indicated by
88  * their macro names when they appear in sctp_net_table.
89  */
90 #define SCTP_RTO_MIN_IDX       0
91 #define SCTP_RTO_MAX_IDX       1
92 #define SCTP_PF_RETRANS_IDX    2
93 #define SCTP_PS_RETRANS_IDX    3
94 
95 static struct ctl_table sctp_net_table[] = {
96 	[SCTP_RTO_MIN_IDX] = {
97 		.procname	= "rto_min",
98 		.data		= &init_net.sctp.rto_min,
99 		.maxlen		= sizeof(unsigned int),
100 		.mode		= 0644,
101 		.proc_handler	= proc_sctp_do_rto_min,
102 		.extra1         = SYSCTL_ONE,
103 		.extra2         = &init_net.sctp.rto_max
104 	},
105 	[SCTP_RTO_MAX_IDX] =  {
106 		.procname	= "rto_max",
107 		.data		= &init_net.sctp.rto_max,
108 		.maxlen		= sizeof(unsigned int),
109 		.mode		= 0644,
110 		.proc_handler	= proc_sctp_do_rto_max,
111 		.extra1         = &init_net.sctp.rto_min,
112 		.extra2         = &timer_max
113 	},
114 	[SCTP_PF_RETRANS_IDX] = {
115 		.procname	= "pf_retrans",
116 		.data		= &init_net.sctp.pf_retrans,
117 		.maxlen		= sizeof(int),
118 		.mode		= 0644,
119 		.proc_handler	= proc_dointvec_minmax,
120 		.extra1		= SYSCTL_ZERO,
121 		.extra2		= &init_net.sctp.ps_retrans,
122 	},
123 	[SCTP_PS_RETRANS_IDX] = {
124 		.procname	= "ps_retrans",
125 		.data		= &init_net.sctp.ps_retrans,
126 		.maxlen		= sizeof(int),
127 		.mode		= 0644,
128 		.proc_handler	= proc_dointvec_minmax,
129 		.extra1		= &init_net.sctp.pf_retrans,
130 		.extra2		= &ps_retrans_max,
131 	},
132 	{
133 		.procname	= "rto_initial",
134 		.data		= &init_net.sctp.rto_initial,
135 		.maxlen		= sizeof(unsigned int),
136 		.mode		= 0644,
137 		.proc_handler	= proc_dointvec_minmax,
138 		.extra1         = SYSCTL_ONE,
139 		.extra2         = &timer_max
140 	},
141 	{
142 		.procname	= "rto_alpha_exp_divisor",
143 		.data		= &init_net.sctp.rto_alpha,
144 		.maxlen		= sizeof(int),
145 		.mode		= 0644,
146 		.proc_handler	= proc_sctp_do_alpha_beta,
147 		.extra1		= &rto_alpha_min,
148 		.extra2		= &rto_alpha_max,
149 	},
150 	{
151 		.procname	= "rto_beta_exp_divisor",
152 		.data		= &init_net.sctp.rto_beta,
153 		.maxlen		= sizeof(int),
154 		.mode		= 0644,
155 		.proc_handler	= proc_sctp_do_alpha_beta,
156 		.extra1		= &rto_beta_min,
157 		.extra2		= &rto_beta_max,
158 	},
159 	{
160 		.procname	= "max_burst",
161 		.data		= &init_net.sctp.max_burst,
162 		.maxlen		= sizeof(int),
163 		.mode		= 0644,
164 		.proc_handler	= proc_dointvec_minmax,
165 		.extra1		= SYSCTL_ZERO,
166 		.extra2		= SYSCTL_INT_MAX,
167 	},
168 	{
169 		.procname	= "cookie_preserve_enable",
170 		.data		= &init_net.sctp.cookie_preserve_enable,
171 		.maxlen		= sizeof(int),
172 		.mode		= 0644,
173 		.proc_handler	= proc_dointvec,
174 	},
175 	{
176 		.procname	= "cookie_hmac_alg",
177 		.data		= &init_net.sctp.sctp_hmac_alg,
178 		.maxlen		= 8,
179 		.mode		= 0644,
180 		.proc_handler	= proc_sctp_do_hmac_alg,
181 	},
182 	{
183 		.procname	= "valid_cookie_life",
184 		.data		= &init_net.sctp.valid_cookie_life,
185 		.maxlen		= sizeof(unsigned int),
186 		.mode		= 0644,
187 		.proc_handler	= proc_dointvec_minmax,
188 		.extra1         = SYSCTL_ONE,
189 		.extra2         = &timer_max
190 	},
191 	{
192 		.procname	= "sack_timeout",
193 		.data		= &init_net.sctp.sack_timeout,
194 		.maxlen		= sizeof(int),
195 		.mode		= 0644,
196 		.proc_handler	= proc_dointvec_minmax,
197 		.extra1         = &sack_timer_min,
198 		.extra2         = &sack_timer_max,
199 	},
200 	{
201 		.procname	= "hb_interval",
202 		.data		= &init_net.sctp.hb_interval,
203 		.maxlen		= sizeof(unsigned int),
204 		.mode		= 0644,
205 		.proc_handler	= proc_dointvec_minmax,
206 		.extra1         = SYSCTL_ONE,
207 		.extra2         = &timer_max
208 	},
209 	{
210 		.procname	= "association_max_retrans",
211 		.data		= &init_net.sctp.max_retrans_association,
212 		.maxlen		= sizeof(int),
213 		.mode		= 0644,
214 		.proc_handler	= proc_dointvec_minmax,
215 		.extra1		= SYSCTL_ONE,
216 		.extra2		= SYSCTL_INT_MAX,
217 	},
218 	{
219 		.procname	= "path_max_retrans",
220 		.data		= &init_net.sctp.max_retrans_path,
221 		.maxlen		= sizeof(int),
222 		.mode		= 0644,
223 		.proc_handler	= proc_dointvec_minmax,
224 		.extra1		= SYSCTL_ONE,
225 		.extra2		= SYSCTL_INT_MAX,
226 	},
227 	{
228 		.procname	= "max_init_retransmits",
229 		.data		= &init_net.sctp.max_retrans_init,
230 		.maxlen		= sizeof(int),
231 		.mode		= 0644,
232 		.proc_handler	= proc_dointvec_minmax,
233 		.extra1		= SYSCTL_ONE,
234 		.extra2		= SYSCTL_INT_MAX,
235 	},
236 	{
237 		.procname	= "sndbuf_policy",
238 		.data		= &init_net.sctp.sndbuf_policy,
239 		.maxlen		= sizeof(int),
240 		.mode		= 0644,
241 		.proc_handler	= proc_dointvec,
242 	},
243 	{
244 		.procname	= "rcvbuf_policy",
245 		.data		= &init_net.sctp.rcvbuf_policy,
246 		.maxlen		= sizeof(int),
247 		.mode		= 0644,
248 		.proc_handler	= proc_dointvec,
249 	},
250 	{
251 		.procname	= "default_auto_asconf",
252 		.data		= &init_net.sctp.default_auto_asconf,
253 		.maxlen		= sizeof(int),
254 		.mode		= 0644,
255 		.proc_handler	= proc_dointvec,
256 	},
257 	{
258 		.procname	= "addip_enable",
259 		.data		= &init_net.sctp.addip_enable,
260 		.maxlen		= sizeof(int),
261 		.mode		= 0644,
262 		.proc_handler	= proc_dointvec,
263 	},
264 	{
265 		.procname	= "addip_noauth_enable",
266 		.data		= &init_net.sctp.addip_noauth,
267 		.maxlen		= sizeof(int),
268 		.mode		= 0644,
269 		.proc_handler	= proc_dointvec,
270 	},
271 	{
272 		.procname	= "prsctp_enable",
273 		.data		= &init_net.sctp.prsctp_enable,
274 		.maxlen		= sizeof(int),
275 		.mode		= 0644,
276 		.proc_handler	= proc_dointvec,
277 	},
278 	{
279 		.procname	= "reconf_enable",
280 		.data		= &init_net.sctp.reconf_enable,
281 		.maxlen		= sizeof(int),
282 		.mode		= 0644,
283 		.proc_handler	= proc_dointvec,
284 	},
285 	{
286 		.procname	= "auth_enable",
287 		.data		= &init_net.sctp.auth_enable,
288 		.maxlen		= sizeof(int),
289 		.mode		= 0644,
290 		.proc_handler	= proc_sctp_do_auth,
291 	},
292 	{
293 		.procname	= "intl_enable",
294 		.data		= &init_net.sctp.intl_enable,
295 		.maxlen		= sizeof(int),
296 		.mode		= 0644,
297 		.proc_handler	= proc_dointvec,
298 	},
299 	{
300 		.procname	= "ecn_enable",
301 		.data		= &init_net.sctp.ecn_enable,
302 		.maxlen		= sizeof(int),
303 		.mode		= 0644,
304 		.proc_handler	= proc_dointvec,
305 	},
306 	{
307 		.procname	= "plpmtud_probe_interval",
308 		.data		= &init_net.sctp.probe_interval,
309 		.maxlen		= sizeof(int),
310 		.mode		= 0644,
311 		.proc_handler	= proc_sctp_do_probe_interval,
312 	},
313 	{
314 		.procname	= "udp_port",
315 		.data		= &init_net.sctp.udp_port,
316 		.maxlen		= sizeof(int),
317 		.mode		= 0644,
318 		.proc_handler	= proc_sctp_do_udp_port,
319 		.extra1		= SYSCTL_ZERO,
320 		.extra2		= &udp_port_max,
321 	},
322 	{
323 		.procname	= "encap_port",
324 		.data		= &init_net.sctp.encap_port,
325 		.maxlen		= sizeof(int),
326 		.mode		= 0644,
327 		.proc_handler	= proc_dointvec_minmax,
328 		.extra1		= SYSCTL_ZERO,
329 		.extra2		= &udp_port_max,
330 	},
331 	{
332 		.procname	= "addr_scope_policy",
333 		.data		= &init_net.sctp.scope_policy,
334 		.maxlen		= sizeof(int),
335 		.mode		= 0644,
336 		.proc_handler	= proc_dointvec_minmax,
337 		.extra1		= SYSCTL_ZERO,
338 		.extra2		= &addr_scope_max,
339 	},
340 	{
341 		.procname	= "rwnd_update_shift",
342 		.data		= &init_net.sctp.rwnd_upd_shift,
343 		.maxlen		= sizeof(int),
344 		.mode		= 0644,
345 		.proc_handler	= &proc_dointvec_minmax,
346 		.extra1		= SYSCTL_ONE,
347 		.extra2		= &rwnd_scale_max,
348 	},
349 	{
350 		.procname	= "max_autoclose",
351 		.data		= &init_net.sctp.max_autoclose,
352 		.maxlen		= sizeof(unsigned long),
353 		.mode		= 0644,
354 		.proc_handler	= &proc_doulongvec_minmax,
355 		.extra1		= &max_autoclose_min,
356 		.extra2		= &max_autoclose_max,
357 	},
358 #ifdef CONFIG_NET_L3_MASTER_DEV
359 	{
360 		.procname	= "l3mdev_accept",
361 		.data		= &init_net.sctp.l3mdev_accept,
362 		.maxlen		= sizeof(int),
363 		.mode		= 0644,
364 		.proc_handler	= proc_dointvec_minmax,
365 		.extra1		= SYSCTL_ZERO,
366 		.extra2		= SYSCTL_ONE,
367 	},
368 #endif
369 	{
370 		.procname	= "pf_enable",
371 		.data		= &init_net.sctp.pf_enable,
372 		.maxlen		= sizeof(int),
373 		.mode		= 0644,
374 		.proc_handler	= proc_dointvec,
375 	},
376 	{
377 		.procname	= "pf_expose",
378 		.data		= &init_net.sctp.pf_expose,
379 		.maxlen		= sizeof(int),
380 		.mode		= 0644,
381 		.proc_handler	= proc_dointvec_minmax,
382 		.extra1		= SYSCTL_ZERO,
383 		.extra2		= &pf_expose_max,
384 	},
385 };
386 
387 static int proc_sctp_do_hmac_alg(const struct ctl_table *ctl, int write,
388 				 void *buffer, size_t *lenp, loff_t *ppos)
389 {
390 	struct net *net = container_of(ctl->data, struct net,
391 				       sctp.sctp_hmac_alg);
392 	struct ctl_table tbl;
393 	bool changed = false;
394 	char *none = "none";
395 	char tmp[8] = {0};
396 	int ret;
397 
398 	memset(&tbl, 0, sizeof(struct ctl_table));
399 
400 	if (write) {
401 		tbl.data = tmp;
402 		tbl.maxlen = sizeof(tmp);
403 	} else {
404 		tbl.data = net->sctp.sctp_hmac_alg ? : none;
405 		tbl.maxlen = strlen(tbl.data);
406 	}
407 
408 	ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
409 	if (write && ret == 0) {
410 #ifdef CONFIG_CRYPTO_MD5
411 		if (!strncmp(tmp, "md5", 3)) {
412 			net->sctp.sctp_hmac_alg = "md5";
413 			changed = true;
414 		}
415 #endif
416 #ifdef CONFIG_CRYPTO_SHA1
417 		if (!strncmp(tmp, "sha1", 4)) {
418 			net->sctp.sctp_hmac_alg = "sha1";
419 			changed = true;
420 		}
421 #endif
422 		if (!strncmp(tmp, "none", 4)) {
423 			net->sctp.sctp_hmac_alg = NULL;
424 			changed = true;
425 		}
426 		if (!changed)
427 			ret = -EINVAL;
428 	}
429 
430 	return ret;
431 }
432 
433 static int proc_sctp_do_rto_min(const struct ctl_table *ctl, int write,
434 				void *buffer, size_t *lenp, loff_t *ppos)
435 {
436 	struct net *net = container_of(ctl->data, struct net, sctp.rto_min);
437 	unsigned int min = *(unsigned int *) ctl->extra1;
438 	unsigned int max = *(unsigned int *) ctl->extra2;
439 	struct ctl_table tbl;
440 	int ret, new_value;
441 
442 	memset(&tbl, 0, sizeof(struct ctl_table));
443 	tbl.maxlen = sizeof(unsigned int);
444 
445 	if (write)
446 		tbl.data = &new_value;
447 	else
448 		tbl.data = &net->sctp.rto_min;
449 
450 	ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
451 	if (write && ret == 0) {
452 		if (new_value > max || new_value < min)
453 			return -EINVAL;
454 
455 		net->sctp.rto_min = new_value;
456 	}
457 
458 	return ret;
459 }
460 
461 static int proc_sctp_do_rto_max(const struct ctl_table *ctl, int write,
462 				void *buffer, size_t *lenp, loff_t *ppos)
463 {
464 	struct net *net = container_of(ctl->data, struct net, sctp.rto_max);
465 	unsigned int min = *(unsigned int *) ctl->extra1;
466 	unsigned int max = *(unsigned int *) ctl->extra2;
467 	struct ctl_table tbl;
468 	int ret, new_value;
469 
470 	memset(&tbl, 0, sizeof(struct ctl_table));
471 	tbl.maxlen = sizeof(unsigned int);
472 
473 	if (write)
474 		tbl.data = &new_value;
475 	else
476 		tbl.data = &net->sctp.rto_max;
477 
478 	ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
479 	if (write && ret == 0) {
480 		if (new_value > max || new_value < min)
481 			return -EINVAL;
482 
483 		net->sctp.rto_max = new_value;
484 	}
485 
486 	return ret;
487 }
488 
489 static int proc_sctp_do_alpha_beta(const struct ctl_table *ctl, int write,
490 				   void *buffer, size_t *lenp, loff_t *ppos)
491 {
492 	if (write)
493 		pr_warn_once("Changing rto_alpha or rto_beta may lead to "
494 			     "suboptimal rtt/srtt estimations!\n");
495 
496 	return proc_dointvec_minmax(ctl, write, buffer, lenp, ppos);
497 }
498 
499 static int proc_sctp_do_auth(const struct ctl_table *ctl, int write,
500 			     void *buffer, size_t *lenp, loff_t *ppos)
501 {
502 	struct net *net = container_of(ctl->data, struct net, sctp.auth_enable);
503 	struct ctl_table tbl;
504 	int new_value, ret;
505 
506 	memset(&tbl, 0, sizeof(struct ctl_table));
507 	tbl.maxlen = sizeof(unsigned int);
508 
509 	if (write)
510 		tbl.data = &new_value;
511 	else
512 		tbl.data = &net->sctp.auth_enable;
513 
514 	ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
515 	if (write && ret == 0) {
516 		struct sock *sk = net->sctp.ctl_sock;
517 
518 		net->sctp.auth_enable = new_value;
519 		/* Update the value in the control socket */
520 		lock_sock(sk);
521 		sctp_sk(sk)->ep->auth_enable = new_value;
522 		release_sock(sk);
523 	}
524 
525 	return ret;
526 }
527 
528 static int proc_sctp_do_udp_port(const struct ctl_table *ctl, int write,
529 				 void *buffer, size_t *lenp, loff_t *ppos)
530 {
531 	struct net *net = container_of(ctl->data, struct net, sctp.udp_port);
532 	unsigned int min = *(unsigned int *)ctl->extra1;
533 	unsigned int max = *(unsigned int *)ctl->extra2;
534 	struct ctl_table tbl;
535 	int ret, new_value;
536 
537 	memset(&tbl, 0, sizeof(struct ctl_table));
538 	tbl.maxlen = sizeof(unsigned int);
539 
540 	if (write)
541 		tbl.data = &new_value;
542 	else
543 		tbl.data = &net->sctp.udp_port;
544 
545 	ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
546 	if (write && ret == 0) {
547 		struct sock *sk = net->sctp.ctl_sock;
548 
549 		if (new_value > max || new_value < min)
550 			return -EINVAL;
551 
552 		net->sctp.udp_port = new_value;
553 		sctp_udp_sock_stop(net);
554 		if (new_value) {
555 			ret = sctp_udp_sock_start(net);
556 			if (ret)
557 				net->sctp.udp_port = 0;
558 		}
559 
560 		/* Update the value in the control socket */
561 		lock_sock(sk);
562 		sctp_sk(sk)->udp_port = htons(net->sctp.udp_port);
563 		release_sock(sk);
564 	}
565 
566 	return ret;
567 }
568 
569 static int proc_sctp_do_probe_interval(const struct ctl_table *ctl, int write,
570 				       void *buffer, size_t *lenp, loff_t *ppos)
571 {
572 	struct net *net = container_of(ctl->data, struct net,
573 				       sctp.probe_interval);
574 	struct ctl_table tbl;
575 	int ret, new_value;
576 
577 	memset(&tbl, 0, sizeof(struct ctl_table));
578 	tbl.maxlen = sizeof(unsigned int);
579 
580 	if (write)
581 		tbl.data = &new_value;
582 	else
583 		tbl.data = &net->sctp.probe_interval;
584 
585 	ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
586 	if (write && ret == 0) {
587 		if (new_value && new_value < SCTP_PROBE_TIMER_MIN)
588 			return -EINVAL;
589 
590 		net->sctp.probe_interval = new_value;
591 	}
592 
593 	return ret;
594 }
595 
596 int sctp_sysctl_net_register(struct net *net)
597 {
598 	size_t table_size = ARRAY_SIZE(sctp_net_table);
599 	struct ctl_table *table;
600 	int i;
601 
602 	table = kmemdup(sctp_net_table, sizeof(sctp_net_table), GFP_KERNEL);
603 	if (!table)
604 		return -ENOMEM;
605 
606 	for (i = 0; i < table_size; i++)
607 		table[i].data += (char *)(&net->sctp) - (char *)&init_net.sctp;
608 
609 	table[SCTP_RTO_MIN_IDX].extra2 = &net->sctp.rto_max;
610 	table[SCTP_RTO_MAX_IDX].extra1 = &net->sctp.rto_min;
611 	table[SCTP_PF_RETRANS_IDX].extra2 = &net->sctp.ps_retrans;
612 	table[SCTP_PS_RETRANS_IDX].extra1 = &net->sctp.pf_retrans;
613 
614 	net->sctp.sysctl_header = register_net_sysctl_sz(net, "net/sctp",
615 							 table, table_size);
616 	if (net->sctp.sysctl_header == NULL) {
617 		kfree(table);
618 		return -ENOMEM;
619 	}
620 	return 0;
621 }
622 
623 void sctp_sysctl_net_unregister(struct net *net)
624 {
625 	const struct ctl_table *table;
626 
627 	table = net->sctp.sysctl_header->ctl_table_arg;
628 	unregister_net_sysctl_table(net->sctp.sysctl_header);
629 	kfree(table);
630 }
631 
632 static struct ctl_table_header *sctp_sysctl_header;
633 
634 /* Sysctl registration.  */
635 void sctp_sysctl_register(void)
636 {
637 	sctp_sysctl_header = register_net_sysctl(&init_net, "net/sctp", sctp_table);
638 }
639 
640 /* Sysctl deregistration.  */
641 void sctp_sysctl_unregister(void)
642 {
643 	unregister_net_sysctl_table(sctp_sysctl_header);
644 }
645