1 // SPDX-License-Identifier: GPL-2.0
3 * sysctl_net_ipv4.c: sysctl interface to net IPV4 subsystem.
5 * Begun April 1, 1996, Mike Shaver.
6 * Added /proc/sys/net/ipv4 directory entry (empty =) ). [MS]
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>
22 #include <net/route.h>
25 #include <net/cipso_ipv4.h>
26 #include <net/inet_frag.h>
28 #include <net/protocol.h>
33 static int thousand = 1000;
34 static int gso_max_segs = GSO_MAX_SEGS;
35 static int tcp_retr1_max = 255;
36 static int ip_local_port_range_min[] = { 1, 1 };
37 static int ip_local_port_range_max[] = { 65535, 65535 };
38 static int tcp_adv_win_scale_min = -31;
39 static int tcp_adv_win_scale_max = 31;
40 static int tcp_min_snd_mss_min = TCP_MIN_SND_MSS;
41 static int tcp_min_snd_mss_max = 65535;
42 static int ip_privileged_port_min;
43 static int ip_privileged_port_max = 65535;
44 static int ip_ttl_min = 1;
45 static int ip_ttl_max = 255;
46 static int tcp_syn_retries_min = 1;
47 static int tcp_syn_retries_max = MAX_TCP_SYNCNT;
48 static int ip_ping_group_range_min[] = { 0, 0 };
49 static int ip_ping_group_range_max[] = { GID_T_MAX, GID_T_MAX };
50 static int one_day_secs = 24 * 3600;
53 static int sysctl_tcp_low_latency __read_mostly;
55 /* Update system visible IP port range */
56 static void set_local_port_range(struct net *net, int range[2])
58 bool same_parity = !((range[0] ^ range[1]) & 1);
60 write_seqlock_bh(&net->ipv4.ip_local_ports.lock);
61 if (same_parity && !net->ipv4.ip_local_ports.warned) {
62 net->ipv4.ip_local_ports.warned = true;
63 pr_err_ratelimited("ip_local_port_range: prefer different parity for start/end values.\n");
65 net->ipv4.ip_local_ports.range[0] = range[0];
66 net->ipv4.ip_local_ports.range[1] = range[1];
67 write_sequnlock_bh(&net->ipv4.ip_local_ports.lock);
70 /* Validate changes from /proc interface. */
71 static int ipv4_local_port_range(struct ctl_table *table, int write,
73 size_t *lenp, loff_t *ppos)
76 container_of(table->data, struct net, ipv4.ip_local_ports.range);
79 struct ctl_table tmp = {
81 .maxlen = sizeof(range),
83 .extra1 = &ip_local_port_range_min,
84 .extra2 = &ip_local_port_range_max,
87 inet_get_local_port_range(net, &range[0], &range[1]);
89 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
91 if (write && ret == 0) {
92 /* Ensure that the upper limit is not smaller than the lower,
93 * and that the lower does not encroach upon the privileged
96 if ((range[1] < range[0]) ||
97 (range[0] < net->ipv4.sysctl_ip_prot_sock))
100 set_local_port_range(net, range);
106 /* Validate changes from /proc interface. */
107 static int ipv4_privileged_ports(struct ctl_table *table, int write,
108 void __user *buffer, size_t *lenp, loff_t *ppos)
110 struct net *net = container_of(table->data, struct net,
111 ipv4.sysctl_ip_prot_sock);
115 struct ctl_table tmp = {
117 .maxlen = sizeof(pports),
119 .extra1 = &ip_privileged_port_min,
120 .extra2 = &ip_privileged_port_max,
123 pports = net->ipv4.sysctl_ip_prot_sock;
125 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
127 if (write && ret == 0) {
128 inet_get_local_port_range(net, &range[0], &range[1]);
129 /* Ensure that the local port range doesn't overlap with the
130 * privileged port range.
132 if (range[0] < pports)
135 net->ipv4.sysctl_ip_prot_sock = pports;
141 static void inet_get_ping_group_range_table(struct ctl_table *table, kgid_t *low, kgid_t *high)
143 kgid_t *data = table->data;
145 container_of(table->data, struct net, ipv4.ping_group_range.range);
148 seq = read_seqbegin(&net->ipv4.ping_group_range.lock);
152 } while (read_seqretry(&net->ipv4.ping_group_range.lock, seq));
155 /* Update system visible IP port range */
156 static void set_ping_group_range(struct ctl_table *table, kgid_t low, kgid_t high)
158 kgid_t *data = table->data;
160 container_of(table->data, struct net, ipv4.ping_group_range.range);
161 write_seqlock(&net->ipv4.ping_group_range.lock);
164 write_sequnlock(&net->ipv4.ping_group_range.lock);
167 /* Validate changes from /proc interface. */
168 static int ipv4_ping_group_range(struct ctl_table *table, int write,
170 size_t *lenp, loff_t *ppos)
172 struct user_namespace *user_ns = current_user_ns();
176 struct ctl_table tmp = {
178 .maxlen = sizeof(urange),
180 .extra1 = &ip_ping_group_range_min,
181 .extra2 = &ip_ping_group_range_max,
184 inet_get_ping_group_range_table(table, &low, &high);
185 urange[0] = from_kgid_munged(user_ns, low);
186 urange[1] = from_kgid_munged(user_ns, high);
187 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
189 if (write && ret == 0) {
190 low = make_kgid(user_ns, urange[0]);
191 high = make_kgid(user_ns, urange[1]);
192 if (!gid_valid(low) || !gid_valid(high))
194 if (urange[1] < urange[0] || gid_lt(high, low)) {
195 low = make_kgid(&init_user_ns, 1);
196 high = make_kgid(&init_user_ns, 0);
198 set_ping_group_range(table, low, high);
204 static int proc_tcp_congestion_control(struct ctl_table *ctl, int write,
205 void __user *buffer, size_t *lenp, loff_t *ppos)
207 char val[TCP_CA_NAME_MAX];
208 struct ctl_table tbl = {
210 .maxlen = TCP_CA_NAME_MAX,
214 tcp_get_default_congestion_control(val);
216 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
217 if (write && ret == 0)
218 ret = tcp_set_default_congestion_control(val);
222 static int proc_tcp_available_congestion_control(struct ctl_table *ctl,
224 void __user *buffer, size_t *lenp,
227 struct ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX, };
230 tbl.data = kmalloc(tbl.maxlen, GFP_USER);
233 tcp_get_available_congestion_control(tbl.data, TCP_CA_BUF_MAX);
234 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
239 static int proc_allowed_congestion_control(struct ctl_table *ctl,
241 void __user *buffer, size_t *lenp,
244 struct ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX };
247 tbl.data = kmalloc(tbl.maxlen, GFP_USER);
251 tcp_get_allowed_congestion_control(tbl.data, tbl.maxlen);
252 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
253 if (write && ret == 0)
254 ret = tcp_set_allowed_congestion_control(tbl.data);
259 static int proc_tcp_fastopen_key(struct ctl_table *ctl, int write,
260 void __user *buffer, size_t *lenp,
263 struct ctl_table tbl = { .maxlen = (TCP_FASTOPEN_KEY_LENGTH * 2 + 10) };
264 struct tcp_fastopen_context *ctxt;
265 u32 user_key[4]; /* 16 bytes, matching TCP_FASTOPEN_KEY_LENGTH */
269 tbl.data = kmalloc(tbl.maxlen, GFP_KERNEL);
274 ctxt = rcu_dereference(tcp_fastopen_ctx);
276 memcpy(key, ctxt->key, TCP_FASTOPEN_KEY_LENGTH);
278 memset(key, 0, sizeof(key));
281 for (i = 0; i < ARRAY_SIZE(key); i++)
282 user_key[i] = le32_to_cpu(key[i]);
284 snprintf(tbl.data, tbl.maxlen, "%08x-%08x-%08x-%08x",
285 user_key[0], user_key[1], user_key[2], user_key[3]);
286 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
288 if (write && ret == 0) {
289 if (sscanf(tbl.data, "%x-%x-%x-%x", user_key, user_key + 1,
290 user_key + 2, user_key + 3) != 4) {
294 /* Generate a dummy secret but don't publish it. This
295 * is needed so we don't regenerate a new key on the
296 * first invocation of tcp_fastopen_cookie_gen
298 tcp_fastopen_init_key_once(false);
300 for (i = 0; i < ARRAY_SIZE(user_key); i++)
301 key[i] = cpu_to_le32(user_key[i]);
303 tcp_fastopen_reset_cipher(key, TCP_FASTOPEN_KEY_LENGTH);
307 pr_debug("proc FO key set 0x%x-%x-%x-%x <- 0x%s: %u\n",
308 user_key[0], user_key[1], user_key[2], user_key[3],
309 (char *)tbl.data, ret);
314 static int proc_tfo_blackhole_detect_timeout(struct ctl_table *table,
317 size_t *lenp, loff_t *ppos)
321 ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
322 if (write && ret == 0)
323 tcp_fastopen_active_timeout_reset();
328 static int proc_tcp_available_ulp(struct ctl_table *ctl,
330 void __user *buffer, size_t *lenp,
333 struct ctl_table tbl = { .maxlen = TCP_ULP_BUF_MAX, };
336 tbl.data = kmalloc(tbl.maxlen, GFP_USER);
339 tcp_get_available_ulp(tbl.data, TCP_ULP_BUF_MAX);
340 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
346 static struct ctl_table ipv4_table[] = {
348 .procname = "tcp_retrans_collapse",
349 .data = &sysctl_tcp_retrans_collapse,
350 .maxlen = sizeof(int),
352 .proc_handler = proc_dointvec
355 .procname = "tcp_max_orphans",
356 .data = &sysctl_tcp_max_orphans,
357 .maxlen = sizeof(int),
359 .proc_handler = proc_dointvec
362 .procname = "tcp_fastopen",
363 .data = &sysctl_tcp_fastopen,
364 .maxlen = sizeof(int),
366 .proc_handler = proc_dointvec,
369 .procname = "tcp_fastopen_key",
371 .maxlen = ((TCP_FASTOPEN_KEY_LENGTH * 2) + 10),
372 .proc_handler = proc_tcp_fastopen_key,
375 .procname = "tcp_fastopen_blackhole_timeout_sec",
376 .data = &sysctl_tcp_fastopen_blackhole_timeout,
377 .maxlen = sizeof(int),
379 .proc_handler = proc_tfo_blackhole_detect_timeout,
383 .procname = "tcp_abort_on_overflow",
384 .data = &sysctl_tcp_abort_on_overflow,
385 .maxlen = sizeof(int),
387 .proc_handler = proc_dointvec
390 .procname = "tcp_stdurg",
391 .data = &sysctl_tcp_stdurg,
392 .maxlen = sizeof(int),
394 .proc_handler = proc_dointvec
397 .procname = "tcp_rfc1337",
398 .data = &sysctl_tcp_rfc1337,
399 .maxlen = sizeof(int),
401 .proc_handler = proc_dointvec
404 .procname = "inet_peer_threshold",
405 .data = &inet_peer_threshold,
406 .maxlen = sizeof(int),
408 .proc_handler = proc_dointvec
411 .procname = "inet_peer_minttl",
412 .data = &inet_peer_minttl,
413 .maxlen = sizeof(int),
415 .proc_handler = proc_dointvec_jiffies,
418 .procname = "inet_peer_maxttl",
419 .data = &inet_peer_maxttl,
420 .maxlen = sizeof(int),
422 .proc_handler = proc_dointvec_jiffies,
425 .procname = "tcp_fack",
426 .data = &sysctl_tcp_fack,
427 .maxlen = sizeof(int),
429 .proc_handler = proc_dointvec
432 .procname = "tcp_recovery",
433 .data = &sysctl_tcp_recovery,
434 .maxlen = sizeof(int),
436 .proc_handler = proc_dointvec,
439 .procname = "tcp_max_reordering",
440 .data = &sysctl_tcp_max_reordering,
441 .maxlen = sizeof(int),
443 .proc_handler = proc_dointvec
446 .procname = "tcp_dsack",
447 .data = &sysctl_tcp_dsack,
448 .maxlen = sizeof(int),
450 .proc_handler = proc_dointvec
453 .procname = "tcp_mem",
454 .maxlen = sizeof(sysctl_tcp_mem),
455 .data = &sysctl_tcp_mem,
457 .proc_handler = proc_doulongvec_minmax,
460 .procname = "tcp_wmem",
461 .data = &sysctl_tcp_wmem,
462 .maxlen = sizeof(sysctl_tcp_wmem),
464 .proc_handler = proc_dointvec_minmax,
468 .procname = "tcp_rmem",
469 .data = &sysctl_tcp_rmem,
470 .maxlen = sizeof(sysctl_tcp_rmem),
472 .proc_handler = proc_dointvec_minmax,
476 .procname = "tcp_app_win",
477 .data = &sysctl_tcp_app_win,
478 .maxlen = sizeof(int),
480 .proc_handler = proc_dointvec
483 .procname = "tcp_adv_win_scale",
484 .data = &sysctl_tcp_adv_win_scale,
485 .maxlen = sizeof(int),
487 .proc_handler = proc_dointvec_minmax,
488 .extra1 = &tcp_adv_win_scale_min,
489 .extra2 = &tcp_adv_win_scale_max,
492 .procname = "tcp_frto",
493 .data = &sysctl_tcp_frto,
494 .maxlen = sizeof(int),
496 .proc_handler = proc_dointvec
499 .procname = "tcp_min_rtt_wlen",
500 .data = &sysctl_tcp_min_rtt_wlen,
501 .maxlen = sizeof(int),
503 .proc_handler = proc_dointvec_minmax,
505 .extra2 = &one_day_secs
508 .procname = "tcp_low_latency",
509 .data = &sysctl_tcp_low_latency,
510 .maxlen = sizeof(int),
512 .proc_handler = proc_dointvec
515 .procname = "tcp_no_metrics_save",
516 .data = &sysctl_tcp_nometrics_save,
517 .maxlen = sizeof(int),
519 .proc_handler = proc_dointvec,
522 .procname = "tcp_moderate_rcvbuf",
523 .data = &sysctl_tcp_moderate_rcvbuf,
524 .maxlen = sizeof(int),
526 .proc_handler = proc_dointvec,
529 .procname = "tcp_tso_win_divisor",
530 .data = &sysctl_tcp_tso_win_divisor,
531 .maxlen = sizeof(int),
533 .proc_handler = proc_dointvec,
536 .procname = "tcp_congestion_control",
538 .maxlen = TCP_CA_NAME_MAX,
539 .proc_handler = proc_tcp_congestion_control,
542 .procname = "tcp_workaround_signed_windows",
543 .data = &sysctl_tcp_workaround_signed_windows,
544 .maxlen = sizeof(int),
546 .proc_handler = proc_dointvec
549 .procname = "tcp_limit_output_bytes",
550 .data = &sysctl_tcp_limit_output_bytes,
551 .maxlen = sizeof(int),
553 .proc_handler = proc_dointvec
556 .procname = "tcp_challenge_ack_limit",
557 .data = &sysctl_tcp_challenge_ack_limit,
558 .maxlen = sizeof(int),
560 .proc_handler = proc_dointvec
563 .procname = "tcp_slow_start_after_idle",
564 .data = &sysctl_tcp_slow_start_after_idle,
565 .maxlen = sizeof(int),
567 .proc_handler = proc_dointvec
569 #ifdef CONFIG_NETLABEL
571 .procname = "cipso_cache_enable",
572 .data = &cipso_v4_cache_enabled,
573 .maxlen = sizeof(int),
575 .proc_handler = proc_dointvec,
578 .procname = "cipso_cache_bucket_size",
579 .data = &cipso_v4_cache_bucketsize,
580 .maxlen = sizeof(int),
582 .proc_handler = proc_dointvec,
585 .procname = "cipso_rbm_optfmt",
586 .data = &cipso_v4_rbm_optfmt,
587 .maxlen = sizeof(int),
589 .proc_handler = proc_dointvec,
592 .procname = "cipso_rbm_strictvalid",
593 .data = &cipso_v4_rbm_strictvalid,
594 .maxlen = sizeof(int),
596 .proc_handler = proc_dointvec,
598 #endif /* CONFIG_NETLABEL */
600 .procname = "tcp_available_congestion_control",
601 .maxlen = TCP_CA_BUF_MAX,
603 .proc_handler = proc_tcp_available_congestion_control,
606 .procname = "tcp_allowed_congestion_control",
607 .maxlen = TCP_CA_BUF_MAX,
609 .proc_handler = proc_allowed_congestion_control,
612 .procname = "tcp_thin_linear_timeouts",
613 .data = &sysctl_tcp_thin_linear_timeouts,
614 .maxlen = sizeof(int),
616 .proc_handler = proc_dointvec
619 .procname = "tcp_early_retrans",
620 .data = &sysctl_tcp_early_retrans,
621 .maxlen = sizeof(int),
623 .proc_handler = proc_dointvec_minmax,
628 .procname = "tcp_min_tso_segs",
629 .data = &sysctl_tcp_min_tso_segs,
630 .maxlen = sizeof(int),
632 .proc_handler = proc_dointvec_minmax,
634 .extra2 = &gso_max_segs,
637 .procname = "tcp_pacing_ss_ratio",
638 .data = &sysctl_tcp_pacing_ss_ratio,
639 .maxlen = sizeof(int),
641 .proc_handler = proc_dointvec_minmax,
646 .procname = "tcp_pacing_ca_ratio",
647 .data = &sysctl_tcp_pacing_ca_ratio,
648 .maxlen = sizeof(int),
650 .proc_handler = proc_dointvec_minmax,
655 .procname = "tcp_autocorking",
656 .data = &sysctl_tcp_autocorking,
657 .maxlen = sizeof(int),
659 .proc_handler = proc_dointvec_minmax,
664 .procname = "tcp_invalid_ratelimit",
665 .data = &sysctl_tcp_invalid_ratelimit,
666 .maxlen = sizeof(int),
668 .proc_handler = proc_dointvec_ms_jiffies,
671 .procname = "tcp_available_ulp",
672 .maxlen = TCP_ULP_BUF_MAX,
674 .proc_handler = proc_tcp_available_ulp,
677 .procname = "icmp_msgs_per_sec",
678 .data = &sysctl_icmp_msgs_per_sec,
679 .maxlen = sizeof(int),
681 .proc_handler = proc_dointvec_minmax,
685 .procname = "icmp_msgs_burst",
686 .data = &sysctl_icmp_msgs_burst,
687 .maxlen = sizeof(int),
689 .proc_handler = proc_dointvec_minmax,
693 .procname = "udp_mem",
694 .data = &sysctl_udp_mem,
695 .maxlen = sizeof(sysctl_udp_mem),
697 .proc_handler = proc_doulongvec_minmax,
700 .procname = "udp_rmem_min",
701 .data = &sysctl_udp_rmem_min,
702 .maxlen = sizeof(sysctl_udp_rmem_min),
704 .proc_handler = proc_dointvec_minmax,
708 .procname = "udp_wmem_min",
709 .data = &sysctl_udp_wmem_min,
710 .maxlen = sizeof(sysctl_udp_wmem_min),
712 .proc_handler = proc_dointvec_minmax,
718 static struct ctl_table ipv4_net_table[] = {
720 .procname = "icmp_echo_ignore_all",
721 .data = &init_net.ipv4.sysctl_icmp_echo_ignore_all,
722 .maxlen = sizeof(int),
724 .proc_handler = proc_dointvec
727 .procname = "icmp_echo_ignore_broadcasts",
728 .data = &init_net.ipv4.sysctl_icmp_echo_ignore_broadcasts,
729 .maxlen = sizeof(int),
731 .proc_handler = proc_dointvec
734 .procname = "icmp_ignore_bogus_error_responses",
735 .data = &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses,
736 .maxlen = sizeof(int),
738 .proc_handler = proc_dointvec
741 .procname = "icmp_errors_use_inbound_ifaddr",
742 .data = &init_net.ipv4.sysctl_icmp_errors_use_inbound_ifaddr,
743 .maxlen = sizeof(int),
745 .proc_handler = proc_dointvec
748 .procname = "icmp_ratelimit",
749 .data = &init_net.ipv4.sysctl_icmp_ratelimit,
750 .maxlen = sizeof(int),
752 .proc_handler = proc_dointvec_ms_jiffies,
755 .procname = "icmp_ratemask",
756 .data = &init_net.ipv4.sysctl_icmp_ratemask,
757 .maxlen = sizeof(int),
759 .proc_handler = proc_dointvec
762 .procname = "ping_group_range",
763 .data = &init_net.ipv4.ping_group_range.range,
764 .maxlen = sizeof(gid_t)*2,
766 .proc_handler = ipv4_ping_group_range,
769 .procname = "tcp_ecn",
770 .data = &init_net.ipv4.sysctl_tcp_ecn,
771 .maxlen = sizeof(int),
773 .proc_handler = proc_dointvec
776 .procname = "tcp_ecn_fallback",
777 .data = &init_net.ipv4.sysctl_tcp_ecn_fallback,
778 .maxlen = sizeof(int),
780 .proc_handler = proc_dointvec
783 .procname = "ip_dynaddr",
784 .data = &init_net.ipv4.sysctl_ip_dynaddr,
785 .maxlen = sizeof(int),
787 .proc_handler = proc_dointvec
790 .procname = "ip_early_demux",
791 .data = &init_net.ipv4.sysctl_ip_early_demux,
792 .maxlen = sizeof(int),
794 .proc_handler = proc_dointvec
797 .procname = "udp_early_demux",
798 .data = &init_net.ipv4.sysctl_udp_early_demux,
799 .maxlen = sizeof(int),
801 .proc_handler = proc_douintvec,
804 .procname = "tcp_early_demux",
805 .data = &init_net.ipv4.sysctl_tcp_early_demux,
806 .maxlen = sizeof(int),
808 .proc_handler = proc_douintvec,
811 .procname = "ip_default_ttl",
812 .data = &init_net.ipv4.sysctl_ip_default_ttl,
813 .maxlen = sizeof(int),
815 .proc_handler = proc_dointvec_minmax,
816 .extra1 = &ip_ttl_min,
817 .extra2 = &ip_ttl_max,
820 .procname = "ip_local_port_range",
821 .maxlen = sizeof(init_net.ipv4.ip_local_ports.range),
822 .data = &init_net.ipv4.ip_local_ports.range,
824 .proc_handler = ipv4_local_port_range,
827 .procname = "ip_local_reserved_ports",
828 .data = &init_net.ipv4.sysctl_local_reserved_ports,
831 .proc_handler = proc_do_large_bitmap,
834 .procname = "ip_no_pmtu_disc",
835 .data = &init_net.ipv4.sysctl_ip_no_pmtu_disc,
836 .maxlen = sizeof(int),
838 .proc_handler = proc_dointvec
841 .procname = "ip_forward_use_pmtu",
842 .data = &init_net.ipv4.sysctl_ip_fwd_use_pmtu,
843 .maxlen = sizeof(int),
845 .proc_handler = proc_dointvec,
848 .procname = "ip_nonlocal_bind",
849 .data = &init_net.ipv4.sysctl_ip_nonlocal_bind,
850 .maxlen = sizeof(int),
852 .proc_handler = proc_dointvec
855 .procname = "fwmark_reflect",
856 .data = &init_net.ipv4.sysctl_fwmark_reflect,
857 .maxlen = sizeof(int),
859 .proc_handler = proc_dointvec,
862 .procname = "tcp_fwmark_accept",
863 .data = &init_net.ipv4.sysctl_tcp_fwmark_accept,
864 .maxlen = sizeof(int),
866 .proc_handler = proc_dointvec,
868 #ifdef CONFIG_NET_L3_MASTER_DEV
870 .procname = "tcp_l3mdev_accept",
871 .data = &init_net.ipv4.sysctl_tcp_l3mdev_accept,
872 .maxlen = sizeof(int),
874 .proc_handler = proc_dointvec_minmax,
880 .procname = "tcp_mtu_probing",
881 .data = &init_net.ipv4.sysctl_tcp_mtu_probing,
882 .maxlen = sizeof(int),
884 .proc_handler = proc_dointvec,
887 .procname = "tcp_base_mss",
888 .data = &init_net.ipv4.sysctl_tcp_base_mss,
889 .maxlen = sizeof(int),
891 .proc_handler = proc_dointvec,
894 .procname = "tcp_min_snd_mss",
895 .data = &init_net.ipv4.sysctl_tcp_min_snd_mss,
896 .maxlen = sizeof(int),
898 .proc_handler = proc_dointvec_minmax,
899 .extra1 = &tcp_min_snd_mss_min,
900 .extra2 = &tcp_min_snd_mss_max,
903 .procname = "tcp_probe_threshold",
904 .data = &init_net.ipv4.sysctl_tcp_probe_threshold,
905 .maxlen = sizeof(int),
907 .proc_handler = proc_dointvec,
910 .procname = "tcp_probe_interval",
911 .data = &init_net.ipv4.sysctl_tcp_probe_interval,
912 .maxlen = sizeof(int),
914 .proc_handler = proc_dointvec,
917 .procname = "igmp_link_local_mcast_reports",
918 .data = &init_net.ipv4.sysctl_igmp_llm_reports,
919 .maxlen = sizeof(int),
921 .proc_handler = proc_dointvec
924 .procname = "igmp_max_memberships",
925 .data = &init_net.ipv4.sysctl_igmp_max_memberships,
926 .maxlen = sizeof(int),
928 .proc_handler = proc_dointvec
931 .procname = "igmp_max_msf",
932 .data = &init_net.ipv4.sysctl_igmp_max_msf,
933 .maxlen = sizeof(int),
935 .proc_handler = proc_dointvec
937 #ifdef CONFIG_IP_MULTICAST
939 .procname = "igmp_qrv",
940 .data = &init_net.ipv4.sysctl_igmp_qrv,
941 .maxlen = sizeof(int),
943 .proc_handler = proc_dointvec_minmax,
948 .procname = "tcp_keepalive_time",
949 .data = &init_net.ipv4.sysctl_tcp_keepalive_time,
950 .maxlen = sizeof(int),
952 .proc_handler = proc_dointvec_jiffies,
955 .procname = "tcp_keepalive_probes",
956 .data = &init_net.ipv4.sysctl_tcp_keepalive_probes,
957 .maxlen = sizeof(int),
959 .proc_handler = proc_dointvec
962 .procname = "tcp_keepalive_intvl",
963 .data = &init_net.ipv4.sysctl_tcp_keepalive_intvl,
964 .maxlen = sizeof(int),
966 .proc_handler = proc_dointvec_jiffies,
969 .procname = "tcp_syn_retries",
970 .data = &init_net.ipv4.sysctl_tcp_syn_retries,
971 .maxlen = sizeof(int),
973 .proc_handler = proc_dointvec_minmax,
974 .extra1 = &tcp_syn_retries_min,
975 .extra2 = &tcp_syn_retries_max
978 .procname = "tcp_synack_retries",
979 .data = &init_net.ipv4.sysctl_tcp_synack_retries,
980 .maxlen = sizeof(int),
982 .proc_handler = proc_dointvec
984 #ifdef CONFIG_SYN_COOKIES
986 .procname = "tcp_syncookies",
987 .data = &init_net.ipv4.sysctl_tcp_syncookies,
988 .maxlen = sizeof(int),
990 .proc_handler = proc_dointvec
994 .procname = "tcp_reordering",
995 .data = &init_net.ipv4.sysctl_tcp_reordering,
996 .maxlen = sizeof(int),
998 .proc_handler = proc_dointvec
1001 .procname = "tcp_retries1",
1002 .data = &init_net.ipv4.sysctl_tcp_retries1,
1003 .maxlen = sizeof(int),
1005 .proc_handler = proc_dointvec_minmax,
1006 .extra2 = &tcp_retr1_max
1009 .procname = "tcp_retries2",
1010 .data = &init_net.ipv4.sysctl_tcp_retries2,
1011 .maxlen = sizeof(int),
1013 .proc_handler = proc_dointvec
1016 .procname = "tcp_orphan_retries",
1017 .data = &init_net.ipv4.sysctl_tcp_orphan_retries,
1018 .maxlen = sizeof(int),
1020 .proc_handler = proc_dointvec
1023 .procname = "tcp_fin_timeout",
1024 .data = &init_net.ipv4.sysctl_tcp_fin_timeout,
1025 .maxlen = sizeof(int),
1027 .proc_handler = proc_dointvec_jiffies,
1030 .procname = "tcp_notsent_lowat",
1031 .data = &init_net.ipv4.sysctl_tcp_notsent_lowat,
1032 .maxlen = sizeof(unsigned int),
1034 .proc_handler = proc_douintvec,
1037 .procname = "tcp_tw_reuse",
1038 .data = &init_net.ipv4.sysctl_tcp_tw_reuse,
1039 .maxlen = sizeof(int),
1041 .proc_handler = proc_dointvec
1044 .procname = "tcp_max_tw_buckets",
1045 .data = &init_net.ipv4.tcp_death_row.sysctl_max_tw_buckets,
1046 .maxlen = sizeof(int),
1048 .proc_handler = proc_dointvec
1051 .procname = "tcp_max_syn_backlog",
1052 .data = &init_net.ipv4.sysctl_max_syn_backlog,
1053 .maxlen = sizeof(int),
1055 .proc_handler = proc_dointvec
1057 #ifdef CONFIG_IP_ROUTE_MULTIPATH
1059 .procname = "fib_multipath_use_neigh",
1060 .data = &init_net.ipv4.sysctl_fib_multipath_use_neigh,
1061 .maxlen = sizeof(int),
1063 .proc_handler = proc_dointvec_minmax,
1068 .procname = "fib_multipath_hash_policy",
1069 .data = &init_net.ipv4.sysctl_fib_multipath_hash_policy,
1070 .maxlen = sizeof(int),
1072 .proc_handler = proc_dointvec_minmax,
1078 .procname = "ip_unprivileged_port_start",
1079 .maxlen = sizeof(int),
1080 .data = &init_net.ipv4.sysctl_ip_prot_sock,
1082 .proc_handler = ipv4_privileged_ports,
1084 #ifdef CONFIG_NET_L3_MASTER_DEV
1086 .procname = "udp_l3mdev_accept",
1087 .data = &init_net.ipv4.sysctl_udp_l3mdev_accept,
1088 .maxlen = sizeof(int),
1090 .proc_handler = proc_dointvec_minmax,
1096 .procname = "tcp_sack",
1097 .data = &init_net.ipv4.sysctl_tcp_sack,
1098 .maxlen = sizeof(int),
1100 .proc_handler = proc_dointvec
1103 .procname = "tcp_window_scaling",
1104 .data = &init_net.ipv4.sysctl_tcp_window_scaling,
1105 .maxlen = sizeof(int),
1107 .proc_handler = proc_dointvec
1110 .procname = "tcp_timestamps",
1111 .data = &init_net.ipv4.sysctl_tcp_timestamps,
1112 .maxlen = sizeof(int),
1114 .proc_handler = proc_dointvec
1119 static __net_init int ipv4_sysctl_init_net(struct net *net)
1121 struct ctl_table *table;
1123 table = ipv4_net_table;
1124 if (!net_eq(net, &init_net)) {
1127 table = kmemdup(table, sizeof(ipv4_net_table), GFP_KERNEL);
1131 /* Update the variables to point into the current struct net */
1132 for (i = 0; i < ARRAY_SIZE(ipv4_net_table) - 1; i++)
1133 table[i].data += (void *)net - (void *)&init_net;
1136 net->ipv4.ipv4_hdr = register_net_sysctl(net, "net/ipv4", table);
1137 if (!net->ipv4.ipv4_hdr)
1140 net->ipv4.sysctl_local_reserved_ports = kzalloc(65536 / 8, GFP_KERNEL);
1141 if (!net->ipv4.sysctl_local_reserved_ports)
1147 unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
1149 if (!net_eq(net, &init_net))
1155 static __net_exit void ipv4_sysctl_exit_net(struct net *net)
1157 struct ctl_table *table;
1159 kfree(net->ipv4.sysctl_local_reserved_ports);
1160 table = net->ipv4.ipv4_hdr->ctl_table_arg;
1161 unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
1165 static __net_initdata struct pernet_operations ipv4_sysctl_ops = {
1166 .init = ipv4_sysctl_init_net,
1167 .exit = ipv4_sysctl_exit_net,
1170 static __init int sysctl_ipv4_init(void)
1172 struct ctl_table_header *hdr;
1174 hdr = register_net_sysctl(&init_net, "net/ipv4", ipv4_table);
1178 if (register_pernet_subsys(&ipv4_sysctl_ops)) {
1179 unregister_net_sysctl_table(hdr);
1186 __initcall(sysctl_ipv4_init);