2 * sysctl_net_ipv4.c: sysctl interface to net IPV4 subsystem.
4 * Begun April 1, 1996, Mike Shaver.
5 * Added /proc/sys/net/ipv4 directory entry (empty =) ). [MS]
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>
21 #include <net/route.h>
24 #include <net/cipso_ipv4.h>
25 #include <net/inet_frag.h>
27 #include <net/tcp_memcontrol.h>
30 static int tcp_retr1_max
= 255;
31 static int ip_local_port_range_min
[] = { 1, 1 };
32 static int ip_local_port_range_max
[] = { 65535, 65535 };
33 static int tcp_adv_win_scale_min
= -31;
34 static int tcp_adv_win_scale_max
= 31;
35 static int ip_ttl_min
= 1;
36 static int ip_ttl_max
= 255;
37 static int ip_ping_group_range_min
[] = { 0, 0 };
38 static int ip_ping_group_range_max
[] = { GID_T_MAX
, GID_T_MAX
};
40 /* Update system visible IP port range */
41 static void set_local_port_range(int range
[2])
43 write_seqlock(&sysctl_local_ports
.lock
);
44 sysctl_local_ports
.range
[0] = range
[0];
45 sysctl_local_ports
.range
[1] = range
[1];
46 write_sequnlock(&sysctl_local_ports
.lock
);
49 /* Validate changes from /proc interface. */
50 static int ipv4_local_port_range(ctl_table
*table
, int write
,
52 size_t *lenp
, loff_t
*ppos
)
58 .maxlen
= sizeof(range
),
60 .extra1
= &ip_local_port_range_min
,
61 .extra2
= &ip_local_port_range_max
,
64 inet_get_local_port_range(range
, range
+ 1);
65 ret
= proc_dointvec_minmax(&tmp
, write
, buffer
, lenp
, ppos
);
67 if (write
&& ret
== 0) {
68 if (range
[1] < range
[0])
71 set_local_port_range(range
);
78 static void inet_get_ping_group_range_table(struct ctl_table
*table
, gid_t
*low
, gid_t
*high
)
80 gid_t
*data
= table
->data
;
83 seq
= read_seqbegin(&sysctl_local_ports
.lock
);
87 } while (read_seqretry(&sysctl_local_ports
.lock
, seq
));
90 /* Update system visible IP port range */
91 static void set_ping_group_range(struct ctl_table
*table
, gid_t range
[2])
93 gid_t
*data
= table
->data
;
94 write_seqlock(&sysctl_local_ports
.lock
);
97 write_sequnlock(&sysctl_local_ports
.lock
);
100 /* Validate changes from /proc interface. */
101 static int ipv4_ping_group_range(ctl_table
*table
, int write
,
103 size_t *lenp
, loff_t
*ppos
)
109 .maxlen
= sizeof(range
),
111 .extra1
= &ip_ping_group_range_min
,
112 .extra2
= &ip_ping_group_range_max
,
115 inet_get_ping_group_range_table(table
, range
, range
+ 1);
116 ret
= proc_dointvec_minmax(&tmp
, write
, buffer
, lenp
, ppos
);
118 if (write
&& ret
== 0)
119 set_ping_group_range(table
, range
);
124 static int proc_tcp_congestion_control(ctl_table
*ctl
, int write
,
125 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
127 char val
[TCP_CA_NAME_MAX
];
130 .maxlen
= TCP_CA_NAME_MAX
,
134 tcp_get_default_congestion_control(val
);
136 ret
= proc_dostring(&tbl
, write
, buffer
, lenp
, ppos
);
137 if (write
&& ret
== 0)
138 ret
= tcp_set_default_congestion_control(val
);
142 static int proc_tcp_available_congestion_control(ctl_table
*ctl
,
144 void __user
*buffer
, size_t *lenp
,
147 ctl_table tbl
= { .maxlen
= TCP_CA_BUF_MAX
, };
150 tbl
.data
= kmalloc(tbl
.maxlen
, GFP_USER
);
153 tcp_get_available_congestion_control(tbl
.data
, TCP_CA_BUF_MAX
);
154 ret
= proc_dostring(&tbl
, write
, buffer
, lenp
, ppos
);
159 static int proc_allowed_congestion_control(ctl_table
*ctl
,
161 void __user
*buffer
, size_t *lenp
,
164 ctl_table tbl
= { .maxlen
= TCP_CA_BUF_MAX
};
167 tbl
.data
= kmalloc(tbl
.maxlen
, GFP_USER
);
171 tcp_get_allowed_congestion_control(tbl
.data
, tbl
.maxlen
);
172 ret
= proc_dostring(&tbl
, write
, buffer
, lenp
, ppos
);
173 if (write
&& ret
== 0)
174 ret
= tcp_set_allowed_congestion_control(tbl
.data
);
179 static int ipv4_tcp_mem(ctl_table
*ctl
, int write
,
180 void __user
*buffer
, size_t *lenp
,
184 unsigned long vec
[3];
185 struct net
*net
= current
->nsproxy
->net_ns
;
186 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM
187 struct mem_cgroup
*memcg
;
192 .maxlen
= sizeof(vec
),
197 ctl
->data
= &net
->ipv4
.sysctl_tcp_mem
;
198 return proc_doulongvec_minmax(ctl
, write
, buffer
, lenp
, ppos
);
201 ret
= proc_doulongvec_minmax(&tmp
, write
, buffer
, lenp
, ppos
);
205 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM
207 memcg
= mem_cgroup_from_task(current
);
209 tcp_prot_mem(memcg
, vec
[0], 0);
210 tcp_prot_mem(memcg
, vec
[1], 1);
211 tcp_prot_mem(memcg
, vec
[2], 2);
215 net
->ipv4
.sysctl_tcp_mem
[0] = vec
[0];
216 net
->ipv4
.sysctl_tcp_mem
[1] = vec
[1];
217 net
->ipv4
.sysctl_tcp_mem
[2] = vec
[2];
222 static struct ctl_table ipv4_table
[] = {
224 .procname
= "tcp_timestamps",
225 .data
= &sysctl_tcp_timestamps
,
226 .maxlen
= sizeof(int),
228 .proc_handler
= proc_dointvec
231 .procname
= "tcp_window_scaling",
232 .data
= &sysctl_tcp_window_scaling
,
233 .maxlen
= sizeof(int),
235 .proc_handler
= proc_dointvec
238 .procname
= "tcp_sack",
239 .data
= &sysctl_tcp_sack
,
240 .maxlen
= sizeof(int),
242 .proc_handler
= proc_dointvec
245 .procname
= "tcp_retrans_collapse",
246 .data
= &sysctl_tcp_retrans_collapse
,
247 .maxlen
= sizeof(int),
249 .proc_handler
= proc_dointvec
252 .procname
= "ip_default_ttl",
253 .data
= &sysctl_ip_default_ttl
,
254 .maxlen
= sizeof(int),
256 .proc_handler
= proc_dointvec_minmax
,
257 .extra1
= &ip_ttl_min
,
258 .extra2
= &ip_ttl_max
,
261 .procname
= "ip_no_pmtu_disc",
262 .data
= &ipv4_config
.no_pmtu_disc
,
263 .maxlen
= sizeof(int),
265 .proc_handler
= proc_dointvec
268 .procname
= "ip_nonlocal_bind",
269 .data
= &sysctl_ip_nonlocal_bind
,
270 .maxlen
= sizeof(int),
272 .proc_handler
= proc_dointvec
275 .procname
= "tcp_syn_retries",
276 .data
= &sysctl_tcp_syn_retries
,
277 .maxlen
= sizeof(int),
279 .proc_handler
= proc_dointvec
282 .procname
= "tcp_synack_retries",
283 .data
= &sysctl_tcp_synack_retries
,
284 .maxlen
= sizeof(int),
286 .proc_handler
= proc_dointvec
289 .procname
= "tcp_max_orphans",
290 .data
= &sysctl_tcp_max_orphans
,
291 .maxlen
= sizeof(int),
293 .proc_handler
= proc_dointvec
296 .procname
= "tcp_max_tw_buckets",
297 .data
= &tcp_death_row
.sysctl_max_tw_buckets
,
298 .maxlen
= sizeof(int),
300 .proc_handler
= proc_dointvec
303 .procname
= "ip_dynaddr",
304 .data
= &sysctl_ip_dynaddr
,
305 .maxlen
= sizeof(int),
307 .proc_handler
= proc_dointvec
310 .procname
= "tcp_keepalive_time",
311 .data
= &sysctl_tcp_keepalive_time
,
312 .maxlen
= sizeof(int),
314 .proc_handler
= proc_dointvec_jiffies
,
317 .procname
= "tcp_keepalive_probes",
318 .data
= &sysctl_tcp_keepalive_probes
,
319 .maxlen
= sizeof(int),
321 .proc_handler
= proc_dointvec
324 .procname
= "tcp_keepalive_intvl",
325 .data
= &sysctl_tcp_keepalive_intvl
,
326 .maxlen
= sizeof(int),
328 .proc_handler
= proc_dointvec_jiffies
,
331 .procname
= "tcp_retries1",
332 .data
= &sysctl_tcp_retries1
,
333 .maxlen
= sizeof(int),
335 .proc_handler
= proc_dointvec_minmax
,
336 .extra2
= &tcp_retr1_max
339 .procname
= "tcp_retries2",
340 .data
= &sysctl_tcp_retries2
,
341 .maxlen
= sizeof(int),
343 .proc_handler
= proc_dointvec
346 .procname
= "tcp_fin_timeout",
347 .data
= &sysctl_tcp_fin_timeout
,
348 .maxlen
= sizeof(int),
350 .proc_handler
= proc_dointvec_jiffies
,
352 #ifdef CONFIG_SYN_COOKIES
354 .procname
= "tcp_syncookies",
355 .data
= &sysctl_tcp_syncookies
,
356 .maxlen
= sizeof(int),
358 .proc_handler
= proc_dointvec
362 .procname
= "tcp_tw_recycle",
363 .data
= &tcp_death_row
.sysctl_tw_recycle
,
364 .maxlen
= sizeof(int),
366 .proc_handler
= proc_dointvec
369 .procname
= "tcp_abort_on_overflow",
370 .data
= &sysctl_tcp_abort_on_overflow
,
371 .maxlen
= sizeof(int),
373 .proc_handler
= proc_dointvec
376 .procname
= "tcp_stdurg",
377 .data
= &sysctl_tcp_stdurg
,
378 .maxlen
= sizeof(int),
380 .proc_handler
= proc_dointvec
383 .procname
= "tcp_rfc1337",
384 .data
= &sysctl_tcp_rfc1337
,
385 .maxlen
= sizeof(int),
387 .proc_handler
= proc_dointvec
390 .procname
= "tcp_max_syn_backlog",
391 .data
= &sysctl_max_syn_backlog
,
392 .maxlen
= sizeof(int),
394 .proc_handler
= proc_dointvec
397 .procname
= "ip_local_port_range",
398 .data
= &sysctl_local_ports
.range
,
399 .maxlen
= sizeof(sysctl_local_ports
.range
),
401 .proc_handler
= ipv4_local_port_range
,
404 .procname
= "ip_local_reserved_ports",
405 .data
= NULL
, /* initialized in sysctl_ipv4_init */
408 .proc_handler
= proc_do_large_bitmap
,
411 .procname
= "igmp_max_memberships",
412 .data
= &sysctl_igmp_max_memberships
,
413 .maxlen
= sizeof(int),
415 .proc_handler
= proc_dointvec
418 .procname
= "igmp_max_msf",
419 .data
= &sysctl_igmp_max_msf
,
420 .maxlen
= sizeof(int),
422 .proc_handler
= proc_dointvec
425 .procname
= "inet_peer_threshold",
426 .data
= &inet_peer_threshold
,
427 .maxlen
= sizeof(int),
429 .proc_handler
= proc_dointvec
432 .procname
= "inet_peer_minttl",
433 .data
= &inet_peer_minttl
,
434 .maxlen
= sizeof(int),
436 .proc_handler
= proc_dointvec_jiffies
,
439 .procname
= "inet_peer_maxttl",
440 .data
= &inet_peer_maxttl
,
441 .maxlen
= sizeof(int),
443 .proc_handler
= proc_dointvec_jiffies
,
446 .procname
= "tcp_orphan_retries",
447 .data
= &sysctl_tcp_orphan_retries
,
448 .maxlen
= sizeof(int),
450 .proc_handler
= proc_dointvec
453 .procname
= "tcp_fack",
454 .data
= &sysctl_tcp_fack
,
455 .maxlen
= sizeof(int),
457 .proc_handler
= proc_dointvec
460 .procname
= "tcp_reordering",
461 .data
= &sysctl_tcp_reordering
,
462 .maxlen
= sizeof(int),
464 .proc_handler
= proc_dointvec
467 .procname
= "tcp_ecn",
468 .data
= &sysctl_tcp_ecn
,
469 .maxlen
= sizeof(int),
471 .proc_handler
= proc_dointvec
474 .procname
= "tcp_dsack",
475 .data
= &sysctl_tcp_dsack
,
476 .maxlen
= sizeof(int),
478 .proc_handler
= proc_dointvec
481 .procname
= "tcp_wmem",
482 .data
= &sysctl_tcp_wmem
,
483 .maxlen
= sizeof(sysctl_tcp_wmem
),
485 .proc_handler
= proc_dointvec
488 .procname
= "tcp_rmem",
489 .data
= &sysctl_tcp_rmem
,
490 .maxlen
= sizeof(sysctl_tcp_rmem
),
492 .proc_handler
= proc_dointvec
495 .procname
= "tcp_app_win",
496 .data
= &sysctl_tcp_app_win
,
497 .maxlen
= sizeof(int),
499 .proc_handler
= proc_dointvec
502 .procname
= "tcp_adv_win_scale",
503 .data
= &sysctl_tcp_adv_win_scale
,
504 .maxlen
= sizeof(int),
506 .proc_handler
= proc_dointvec_minmax
,
507 .extra1
= &tcp_adv_win_scale_min
,
508 .extra2
= &tcp_adv_win_scale_max
,
511 .procname
= "tcp_tw_reuse",
512 .data
= &sysctl_tcp_tw_reuse
,
513 .maxlen
= sizeof(int),
515 .proc_handler
= proc_dointvec
518 .procname
= "tcp_frto",
519 .data
= &sysctl_tcp_frto
,
520 .maxlen
= sizeof(int),
522 .proc_handler
= proc_dointvec
525 .procname
= "tcp_frto_response",
526 .data
= &sysctl_tcp_frto_response
,
527 .maxlen
= sizeof(int),
529 .proc_handler
= proc_dointvec
532 .procname
= "tcp_low_latency",
533 .data
= &sysctl_tcp_low_latency
,
534 .maxlen
= sizeof(int),
536 .proc_handler
= proc_dointvec
539 .procname
= "tcp_no_metrics_save",
540 .data
= &sysctl_tcp_nometrics_save
,
541 .maxlen
= sizeof(int),
543 .proc_handler
= proc_dointvec
,
546 .procname
= "tcp_moderate_rcvbuf",
547 .data
= &sysctl_tcp_moderate_rcvbuf
,
548 .maxlen
= sizeof(int),
550 .proc_handler
= proc_dointvec
,
553 .procname
= "tcp_tso_win_divisor",
554 .data
= &sysctl_tcp_tso_win_divisor
,
555 .maxlen
= sizeof(int),
557 .proc_handler
= proc_dointvec
,
560 .procname
= "tcp_congestion_control",
562 .maxlen
= TCP_CA_NAME_MAX
,
563 .proc_handler
= proc_tcp_congestion_control
,
566 .procname
= "tcp_abc",
567 .data
= &sysctl_tcp_abc
,
568 .maxlen
= sizeof(int),
570 .proc_handler
= proc_dointvec
,
573 .procname
= "tcp_mtu_probing",
574 .data
= &sysctl_tcp_mtu_probing
,
575 .maxlen
= sizeof(int),
577 .proc_handler
= proc_dointvec
,
580 .procname
= "tcp_base_mss",
581 .data
= &sysctl_tcp_base_mss
,
582 .maxlen
= sizeof(int),
584 .proc_handler
= proc_dointvec
,
587 .procname
= "tcp_workaround_signed_windows",
588 .data
= &sysctl_tcp_workaround_signed_windows
,
589 .maxlen
= sizeof(int),
591 .proc_handler
= proc_dointvec
593 #ifdef CONFIG_NET_DMA
595 .procname
= "tcp_dma_copybreak",
596 .data
= &sysctl_tcp_dma_copybreak
,
597 .maxlen
= sizeof(int),
599 .proc_handler
= proc_dointvec
603 .procname
= "tcp_slow_start_after_idle",
604 .data
= &sysctl_tcp_slow_start_after_idle
,
605 .maxlen
= sizeof(int),
607 .proc_handler
= proc_dointvec
609 #ifdef CONFIG_NETLABEL
611 .procname
= "cipso_cache_enable",
612 .data
= &cipso_v4_cache_enabled
,
613 .maxlen
= sizeof(int),
615 .proc_handler
= proc_dointvec
,
618 .procname
= "cipso_cache_bucket_size",
619 .data
= &cipso_v4_cache_bucketsize
,
620 .maxlen
= sizeof(int),
622 .proc_handler
= proc_dointvec
,
625 .procname
= "cipso_rbm_optfmt",
626 .data
= &cipso_v4_rbm_optfmt
,
627 .maxlen
= sizeof(int),
629 .proc_handler
= proc_dointvec
,
632 .procname
= "cipso_rbm_strictvalid",
633 .data
= &cipso_v4_rbm_strictvalid
,
634 .maxlen
= sizeof(int),
636 .proc_handler
= proc_dointvec
,
638 #endif /* CONFIG_NETLABEL */
640 .procname
= "tcp_available_congestion_control",
641 .maxlen
= TCP_CA_BUF_MAX
,
643 .proc_handler
= proc_tcp_available_congestion_control
,
646 .procname
= "tcp_allowed_congestion_control",
647 .maxlen
= TCP_CA_BUF_MAX
,
649 .proc_handler
= proc_allowed_congestion_control
,
652 .procname
= "tcp_max_ssthresh",
653 .data
= &sysctl_tcp_max_ssthresh
,
654 .maxlen
= sizeof(int),
656 .proc_handler
= proc_dointvec
,
659 .procname
= "tcp_cookie_size",
660 .data
= &sysctl_tcp_cookie_size
,
661 .maxlen
= sizeof(int),
663 .proc_handler
= proc_dointvec
666 .procname
= "tcp_thin_linear_timeouts",
667 .data
= &sysctl_tcp_thin_linear_timeouts
,
668 .maxlen
= sizeof(int),
670 .proc_handler
= proc_dointvec
673 .procname
= "tcp_thin_dupack",
674 .data
= &sysctl_tcp_thin_dupack
,
675 .maxlen
= sizeof(int),
677 .proc_handler
= proc_dointvec
680 .procname
= "udp_mem",
681 .data
= &sysctl_udp_mem
,
682 .maxlen
= sizeof(sysctl_udp_mem
),
684 .proc_handler
= proc_doulongvec_minmax
,
687 .procname
= "udp_rmem_min",
688 .data
= &sysctl_udp_rmem_min
,
689 .maxlen
= sizeof(sysctl_udp_rmem_min
),
691 .proc_handler
= proc_dointvec_minmax
,
695 .procname
= "udp_wmem_min",
696 .data
= &sysctl_udp_wmem_min
,
697 .maxlen
= sizeof(sysctl_udp_wmem_min
),
699 .proc_handler
= proc_dointvec_minmax
,
705 static struct ctl_table ipv4_net_table
[] = {
707 .procname
= "icmp_echo_ignore_all",
708 .data
= &init_net
.ipv4
.sysctl_icmp_echo_ignore_all
,
709 .maxlen
= sizeof(int),
711 .proc_handler
= proc_dointvec
714 .procname
= "icmp_echo_ignore_broadcasts",
715 .data
= &init_net
.ipv4
.sysctl_icmp_echo_ignore_broadcasts
,
716 .maxlen
= sizeof(int),
718 .proc_handler
= proc_dointvec
721 .procname
= "icmp_ignore_bogus_error_responses",
722 .data
= &init_net
.ipv4
.sysctl_icmp_ignore_bogus_error_responses
,
723 .maxlen
= sizeof(int),
725 .proc_handler
= proc_dointvec
728 .procname
= "icmp_errors_use_inbound_ifaddr",
729 .data
= &init_net
.ipv4
.sysctl_icmp_errors_use_inbound_ifaddr
,
730 .maxlen
= sizeof(int),
732 .proc_handler
= proc_dointvec
735 .procname
= "icmp_ratelimit",
736 .data
= &init_net
.ipv4
.sysctl_icmp_ratelimit
,
737 .maxlen
= sizeof(int),
739 .proc_handler
= proc_dointvec_ms_jiffies
,
742 .procname
= "icmp_ratemask",
743 .data
= &init_net
.ipv4
.sysctl_icmp_ratemask
,
744 .maxlen
= sizeof(int),
746 .proc_handler
= proc_dointvec
749 .procname
= "rt_cache_rebuild_count",
750 .data
= &init_net
.ipv4
.sysctl_rt_cache_rebuild_count
,
751 .maxlen
= sizeof(int),
753 .proc_handler
= proc_dointvec
756 .procname
= "ping_group_range",
757 .data
= &init_net
.ipv4
.sysctl_ping_group_range
,
758 .maxlen
= sizeof(init_net
.ipv4
.sysctl_ping_group_range
),
760 .proc_handler
= ipv4_ping_group_range
,
763 .procname
= "tcp_mem",
764 .maxlen
= sizeof(init_net
.ipv4
.sysctl_tcp_mem
),
766 .proc_handler
= ipv4_tcp_mem
,
771 struct ctl_path net_ipv4_ctl_path
[] = {
772 { .procname
= "net", },
773 { .procname
= "ipv4", },
776 EXPORT_SYMBOL_GPL(net_ipv4_ctl_path
);
778 static __net_init
int ipv4_sysctl_init_net(struct net
*net
)
780 struct ctl_table
*table
;
782 table
= ipv4_net_table
;
783 if (!net_eq(net
, &init_net
)) {
784 table
= kmemdup(table
, sizeof(ipv4_net_table
), GFP_KERNEL
);
789 &net
->ipv4
.sysctl_icmp_echo_ignore_all
;
791 &net
->ipv4
.sysctl_icmp_echo_ignore_broadcasts
;
793 &net
->ipv4
.sysctl_icmp_ignore_bogus_error_responses
;
795 &net
->ipv4
.sysctl_icmp_errors_use_inbound_ifaddr
;
797 &net
->ipv4
.sysctl_icmp_ratelimit
;
799 &net
->ipv4
.sysctl_icmp_ratemask
;
801 &net
->ipv4
.sysctl_rt_cache_rebuild_count
;
803 &net
->ipv4
.sysctl_ping_group_range
;
808 * Sane defaults - nobody may create ping sockets.
809 * Boot scripts should set this to distro-specific group.
811 net
->ipv4
.sysctl_ping_group_range
[0] = 1;
812 net
->ipv4
.sysctl_ping_group_range
[1] = 0;
814 net
->ipv4
.sysctl_rt_cache_rebuild_count
= 4;
818 net
->ipv4
.ipv4_hdr
= register_net_sysctl_table(net
,
819 net_ipv4_ctl_path
, table
);
820 if (net
->ipv4
.ipv4_hdr
== NULL
)
826 if (!net_eq(net
, &init_net
))
832 static __net_exit
void ipv4_sysctl_exit_net(struct net
*net
)
834 struct ctl_table
*table
;
836 table
= net
->ipv4
.ipv4_hdr
->ctl_table_arg
;
837 unregister_net_sysctl_table(net
->ipv4
.ipv4_hdr
);
841 static __net_initdata
struct pernet_operations ipv4_sysctl_ops
= {
842 .init
= ipv4_sysctl_init_net
,
843 .exit
= ipv4_sysctl_exit_net
,
846 static __init
int sysctl_ipv4_init(void)
848 struct ctl_table_header
*hdr
;
851 for (i
= ipv4_table
; i
->procname
; i
++) {
852 if (strcmp(i
->procname
, "ip_local_reserved_ports") == 0) {
853 i
->data
= sysctl_local_reserved_ports
;
860 hdr
= register_sysctl_paths(net_ipv4_ctl_path
, ipv4_table
);
864 if (register_pernet_subsys(&ipv4_sysctl_ops
)) {
865 unregister_sysctl_table(hdr
);
872 __initcall(sysctl_ipv4_init
);