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1/* -*- linux-c -*-
2 * sysctl_net_core.c: sysctl interface to net core subsystem.
3 *
4 * Begun April 1, 1996, Mike Shaver.
5 * Added /proc/sys/net/core directory entry (empty =) ). [MS]
6 */
7
8#include <linux/mm.h>
9#include <linux/sysctl.h>
10#include <linux/module.h>
11#include <linux/socket.h>
12#include <linux/netdevice.h>
13#include <linux/ratelimit.h>
14#include <linux/vmalloc.h>
15#include <linux/init.h>
16#include <linux/slab.h>
17#include <linux/kmemleak.h>
18
19#include <net/ip.h>
20#include <net/sock.h>
21#include <net/net_ratelimit.h>
22#include <net/busy_poll.h>
23#include <net/pkt_sched.h>
24
25static int zero = 0;
26static int one = 1;
27static int min_sndbuf = SOCK_MIN_SNDBUF;
28static int min_rcvbuf = SOCK_MIN_RCVBUF;
29static int max_skb_frags = MAX_SKB_FRAGS;
30
31static int net_msg_warn; /* Unused, but still a sysctl */
32
33#ifdef CONFIG_RPS
34static int rps_sock_flow_sysctl(struct ctl_table *table, int write,
35 void __user *buffer, size_t *lenp, loff_t *ppos)
36{
37 unsigned int orig_size, size;
38 int ret, i;
39 struct ctl_table tmp = {
40 .data = &size,
41 .maxlen = sizeof(size),
42 .mode = table->mode
43 };
44 struct rps_sock_flow_table *orig_sock_table, *sock_table;
45 static DEFINE_MUTEX(sock_flow_mutex);
46
47 mutex_lock(&sock_flow_mutex);
48
49 orig_sock_table = rcu_dereference_protected(rps_sock_flow_table,
50 lockdep_is_held(&sock_flow_mutex));
51 size = orig_size = orig_sock_table ? orig_sock_table->mask + 1 : 0;
52
53 ret = proc_dointvec(&tmp, write, buffer, lenp, ppos);
54
55 if (write) {
56 if (size) {
57 if (size > 1<<29) {
58 /* Enforce limit to prevent overflow */
59 mutex_unlock(&sock_flow_mutex);
60 return -EINVAL;
61 }
62 size = roundup_pow_of_two(size);
63 if (size != orig_size) {
64 sock_table =
65 vmalloc(RPS_SOCK_FLOW_TABLE_SIZE(size));
66 if (!sock_table) {
67 mutex_unlock(&sock_flow_mutex);
68 return -ENOMEM;
69 }
70 rps_cpu_mask = roundup_pow_of_two(nr_cpu_ids) - 1;
71 sock_table->mask = size - 1;
72 } else
73 sock_table = orig_sock_table;
74
75 for (i = 0; i < size; i++)
76 sock_table->ents[i] = RPS_NO_CPU;
77 } else
78 sock_table = NULL;
79
80 if (sock_table != orig_sock_table) {
81 rcu_assign_pointer(rps_sock_flow_table, sock_table);
82 if (sock_table)
83 static_key_slow_inc(&rps_needed);
84 if (orig_sock_table) {
85 static_key_slow_dec(&rps_needed);
86 synchronize_rcu();
87 vfree(orig_sock_table);
88 }
89 }
90 }
91
92 mutex_unlock(&sock_flow_mutex);
93
94 return ret;
95}
96#endif /* CONFIG_RPS */
97
98#ifdef CONFIG_NET_FLOW_LIMIT
99static DEFINE_MUTEX(flow_limit_update_mutex);
100
101static int flow_limit_cpu_sysctl(struct ctl_table *table, int write,
102 void __user *buffer, size_t *lenp,
103 loff_t *ppos)
104{
105 struct sd_flow_limit *cur;
106 struct softnet_data *sd;
107 cpumask_var_t mask;
108 int i, len, ret = 0;
109
110 if (!alloc_cpumask_var(&mask, GFP_KERNEL))
111 return -ENOMEM;
112
113 if (write) {
114 ret = cpumask_parse_user(buffer, *lenp, mask);
115 if (ret)
116 goto done;
117
118 mutex_lock(&flow_limit_update_mutex);
119 len = sizeof(*cur) + netdev_flow_limit_table_len;
120 for_each_possible_cpu(i) {
121 sd = &per_cpu(softnet_data, i);
122 cur = rcu_dereference_protected(sd->flow_limit,
123 lockdep_is_held(&flow_limit_update_mutex));
124 if (cur && !cpumask_test_cpu(i, mask)) {
125 RCU_INIT_POINTER(sd->flow_limit, NULL);
126 synchronize_rcu();
127 kfree(cur);
128 } else if (!cur && cpumask_test_cpu(i, mask)) {
129 cur = kzalloc_node(len, GFP_KERNEL,
130 cpu_to_node(i));
131 if (!cur) {
132 /* not unwinding previous changes */
133 ret = -ENOMEM;
134 goto write_unlock;
135 }
136 cur->num_buckets = netdev_flow_limit_table_len;
137 rcu_assign_pointer(sd->flow_limit, cur);
138 }
139 }
140write_unlock:
141 mutex_unlock(&flow_limit_update_mutex);
142 } else {
143 char kbuf[128];
144
145 if (*ppos || !*lenp) {
146 *lenp = 0;
147 goto done;
148 }
149
150 cpumask_clear(mask);
151 rcu_read_lock();
152 for_each_possible_cpu(i) {
153 sd = &per_cpu(softnet_data, i);
154 if (rcu_dereference(sd->flow_limit))
155 cpumask_set_cpu(i, mask);
156 }
157 rcu_read_unlock();
158
159 len = min(sizeof(kbuf) - 1, *lenp);
160 len = scnprintf(kbuf, len, "%*pb", cpumask_pr_args(mask));
161 if (!len) {
162 *lenp = 0;
163 goto done;
164 }
165 if (len < *lenp)
166 kbuf[len++] = '\n';
167 if (copy_to_user(buffer, kbuf, len)) {
168 ret = -EFAULT;
169 goto done;
170 }
171 *lenp = len;
172 *ppos += len;
173 }
174
175done:
176 free_cpumask_var(mask);
177 return ret;
178}
179
180static int flow_limit_table_len_sysctl(struct ctl_table *table, int write,
181 void __user *buffer, size_t *lenp,
182 loff_t *ppos)
183{
184 unsigned int old, *ptr;
185 int ret;
186
187 mutex_lock(&flow_limit_update_mutex);
188
189 ptr = table->data;
190 old = *ptr;
191 ret = proc_dointvec(table, write, buffer, lenp, ppos);
192 if (!ret && write && !is_power_of_2(*ptr)) {
193 *ptr = old;
194 ret = -EINVAL;
195 }
196
197 mutex_unlock(&flow_limit_update_mutex);
198 return ret;
199}
200#endif /* CONFIG_NET_FLOW_LIMIT */
201
202#ifdef CONFIG_NET_SCHED
203static int set_default_qdisc(struct ctl_table *table, int write,
204 void __user *buffer, size_t *lenp, loff_t *ppos)
205{
206 char id[IFNAMSIZ];
207 struct ctl_table tbl = {
208 .data = id,
209 .maxlen = IFNAMSIZ,
210 };
211 int ret;
212
213 qdisc_get_default(id, IFNAMSIZ);
214
215 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
216 if (write && ret == 0)
217 ret = qdisc_set_default(id);
218 return ret;
219}
220#endif
221
222static int proc_do_rss_key(struct ctl_table *table, int write,
223 void __user *buffer, size_t *lenp, loff_t *ppos)
224{
225 struct ctl_table fake_table;
226 char buf[NETDEV_RSS_KEY_LEN * 3];
227
228 snprintf(buf, sizeof(buf), "%*phC", NETDEV_RSS_KEY_LEN, netdev_rss_key);
229 fake_table.data = buf;
230 fake_table.maxlen = sizeof(buf);
231 return proc_dostring(&fake_table, write, buffer, lenp, ppos);
232}
233
234static struct ctl_table net_core_table[] = {
235#ifdef CONFIG_NET
236 {
237 .procname = "wmem_max",
238 .data = &sysctl_wmem_max,
239 .maxlen = sizeof(int),
240 .mode = 0644,
241 .proc_handler = proc_dointvec_minmax,
242 .extra1 = &min_sndbuf,
243 },
244 {
245 .procname = "rmem_max",
246 .data = &sysctl_rmem_max,
247 .maxlen = sizeof(int),
248 .mode = 0644,
249 .proc_handler = proc_dointvec_minmax,
250 .extra1 = &min_rcvbuf,
251 },
252 {
253 .procname = "wmem_default",
254 .data = &sysctl_wmem_default,
255 .maxlen = sizeof(int),
256 .mode = 0644,
257 .proc_handler = proc_dointvec_minmax,
258 .extra1 = &min_sndbuf,
259 },
260 {
261 .procname = "rmem_default",
262 .data = &sysctl_rmem_default,
263 .maxlen = sizeof(int),
264 .mode = 0644,
265 .proc_handler = proc_dointvec_minmax,
266 .extra1 = &min_rcvbuf,
267 },
268 {
269 .procname = "dev_weight",
270 .data = &weight_p,
271 .maxlen = sizeof(int),
272 .mode = 0644,
273 .proc_handler = proc_dointvec
274 },
275 {
276 .procname = "netdev_max_backlog",
277 .data = &netdev_max_backlog,
278 .maxlen = sizeof(int),
279 .mode = 0644,
280 .proc_handler = proc_dointvec
281 },
282 {
283 .procname = "netdev_rss_key",
284 .data = &netdev_rss_key,
285 .maxlen = sizeof(int),
286 .mode = 0444,
287 .proc_handler = proc_do_rss_key,
288 },
289#ifdef CONFIG_BPF_JIT
290 {
291 .procname = "bpf_jit_enable",
292 .data = &bpf_jit_enable,
293 .maxlen = sizeof(int),
294 .mode = 0644,
295 .proc_handler = proc_dointvec
296 },
297#endif
298 {
299 .procname = "netdev_tstamp_prequeue",
300 .data = &netdev_tstamp_prequeue,
301 .maxlen = sizeof(int),
302 .mode = 0644,
303 .proc_handler = proc_dointvec
304 },
305 {
306 .procname = "message_cost",
307 .data = &net_ratelimit_state.interval,
308 .maxlen = sizeof(int),
309 .mode = 0644,
310 .proc_handler = proc_dointvec_jiffies,
311 },
312 {
313 .procname = "message_burst",
314 .data = &net_ratelimit_state.burst,
315 .maxlen = sizeof(int),
316 .mode = 0644,
317 .proc_handler = proc_dointvec,
318 },
319 {
320 .procname = "optmem_max",
321 .data = &sysctl_optmem_max,
322 .maxlen = sizeof(int),
323 .mode = 0644,
324 .proc_handler = proc_dointvec
325 },
326 {
327 .procname = "tstamp_allow_data",
328 .data = &sysctl_tstamp_allow_data,
329 .maxlen = sizeof(int),
330 .mode = 0644,
331 .proc_handler = proc_dointvec_minmax,
332 .extra1 = &zero,
333 .extra2 = &one
334 },
335#ifdef CONFIG_RPS
336 {
337 .procname = "rps_sock_flow_entries",
338 .maxlen = sizeof(int),
339 .mode = 0644,
340 .proc_handler = rps_sock_flow_sysctl
341 },
342#endif
343#ifdef CONFIG_NET_FLOW_LIMIT
344 {
345 .procname = "flow_limit_cpu_bitmap",
346 .mode = 0644,
347 .proc_handler = flow_limit_cpu_sysctl
348 },
349 {
350 .procname = "flow_limit_table_len",
351 .data = &netdev_flow_limit_table_len,
352 .maxlen = sizeof(int),
353 .mode = 0644,
354 .proc_handler = flow_limit_table_len_sysctl
355 },
356#endif /* CONFIG_NET_FLOW_LIMIT */
357#ifdef CONFIG_NET_RX_BUSY_POLL
358 {
359 .procname = "busy_poll",
360 .data = &sysctl_net_busy_poll,
361 .maxlen = sizeof(unsigned int),
362 .mode = 0644,
363 .proc_handler = proc_dointvec
364 },
365 {
366 .procname = "busy_read",
367 .data = &sysctl_net_busy_read,
368 .maxlen = sizeof(unsigned int),
369 .mode = 0644,
370 .proc_handler = proc_dointvec
371 },
372#endif
373#ifdef CONFIG_NET_SCHED
374 {
375 .procname = "default_qdisc",
376 .mode = 0644,
377 .maxlen = IFNAMSIZ,
378 .proc_handler = set_default_qdisc
379 },
380#endif
381#endif /* CONFIG_NET */
382 {
383 .procname = "netdev_budget",
384 .data = &netdev_budget,
385 .maxlen = sizeof(int),
386 .mode = 0644,
387 .proc_handler = proc_dointvec
388 },
389 {
390 .procname = "warnings",
391 .data = &net_msg_warn,
392 .maxlen = sizeof(int),
393 .mode = 0644,
394 .proc_handler = proc_dointvec
395 },
396 {
397 .procname = "max_skb_frags",
398 .data = &sysctl_max_skb_frags,
399 .maxlen = sizeof(int),
400 .mode = 0644,
401 .proc_handler = proc_dointvec_minmax,
402 .extra1 = &one,
403 .extra2 = &max_skb_frags,
404 },
405 { }
406};
407
408static struct ctl_table netns_core_table[] = {
409 {
410 .procname = "somaxconn",
411 .data = &init_net.core.sysctl_somaxconn,
412 .maxlen = sizeof(int),
413 .mode = 0644,
414 .extra1 = &zero,
415 .proc_handler = proc_dointvec_minmax
416 },
417 { }
418};
419
420static __net_init int sysctl_core_net_init(struct net *net)
421{
422 struct ctl_table *tbl;
423
424 net->core.sysctl_somaxconn = SOMAXCONN;
425
426 tbl = netns_core_table;
427 if (!net_eq(net, &init_net)) {
428 tbl = kmemdup(tbl, sizeof(netns_core_table), GFP_KERNEL);
429 if (tbl == NULL)
430 goto err_dup;
431
432 tbl[0].data = &net->core.sysctl_somaxconn;
433
434 /* Don't export any sysctls to unprivileged users */
435 if (net->user_ns != &init_user_ns) {
436 tbl[0].procname = NULL;
437 }
438 }
439
440 net->core.sysctl_hdr = register_net_sysctl(net, "net/core", tbl);
441 if (net->core.sysctl_hdr == NULL)
442 goto err_reg;
443
444 return 0;
445
446err_reg:
447 if (tbl != netns_core_table)
448 kfree(tbl);
449err_dup:
450 return -ENOMEM;
451}
452
453static __net_exit void sysctl_core_net_exit(struct net *net)
454{
455 struct ctl_table *tbl;
456
457 tbl = net->core.sysctl_hdr->ctl_table_arg;
458 unregister_net_sysctl_table(net->core.sysctl_hdr);
459 BUG_ON(tbl == netns_core_table);
460 kfree(tbl);
461}
462
463static __net_initdata struct pernet_operations sysctl_core_ops = {
464 .init = sysctl_core_net_init,
465 .exit = sysctl_core_net_exit,
466};
467
468static __init int sysctl_core_init(void)
469{
470 register_net_sysctl(&init_net, "net/core", net_core_table);
471 return register_pernet_subsys(&sysctl_core_ops);
472}
473
474fs_initcall(sysctl_core_init);
1/* -*- linux-c -*-
2 * sysctl_net_core.c: sysctl interface to net core subsystem.
3 *
4 * Begun April 1, 1996, Mike Shaver.
5 * Added /proc/sys/net/core directory entry (empty =) ). [MS]
6 */
7
8#include <linux/mm.h>
9#include <linux/sysctl.h>
10#include <linux/module.h>
11#include <linux/socket.h>
12#include <linux/netdevice.h>
13#include <linux/ratelimit.h>
14#include <linux/vmalloc.h>
15#include <linux/init.h>
16#include <linux/slab.h>
17#include <linux/kmemleak.h>
18
19#include <net/ip.h>
20#include <net/sock.h>
21#include <net/net_ratelimit.h>
22
23#ifdef CONFIG_RPS
24static int rps_sock_flow_sysctl(ctl_table *table, int write,
25 void __user *buffer, size_t *lenp, loff_t *ppos)
26{
27 unsigned int orig_size, size;
28 int ret, i;
29 ctl_table tmp = {
30 .data = &size,
31 .maxlen = sizeof(size),
32 .mode = table->mode
33 };
34 struct rps_sock_flow_table *orig_sock_table, *sock_table;
35 static DEFINE_MUTEX(sock_flow_mutex);
36
37 mutex_lock(&sock_flow_mutex);
38
39 orig_sock_table = rcu_dereference_protected(rps_sock_flow_table,
40 lockdep_is_held(&sock_flow_mutex));
41 size = orig_size = orig_sock_table ? orig_sock_table->mask + 1 : 0;
42
43 ret = proc_dointvec(&tmp, write, buffer, lenp, ppos);
44
45 if (write) {
46 if (size) {
47 if (size > 1<<30) {
48 /* Enforce limit to prevent overflow */
49 mutex_unlock(&sock_flow_mutex);
50 return -EINVAL;
51 }
52 size = roundup_pow_of_two(size);
53 if (size != orig_size) {
54 sock_table =
55 vmalloc(RPS_SOCK_FLOW_TABLE_SIZE(size));
56 if (!sock_table) {
57 mutex_unlock(&sock_flow_mutex);
58 return -ENOMEM;
59 }
60
61 sock_table->mask = size - 1;
62 } else
63 sock_table = orig_sock_table;
64
65 for (i = 0; i < size; i++)
66 sock_table->ents[i] = RPS_NO_CPU;
67 } else
68 sock_table = NULL;
69
70 if (sock_table != orig_sock_table) {
71 rcu_assign_pointer(rps_sock_flow_table, sock_table);
72 if (sock_table)
73 static_key_slow_inc(&rps_needed);
74 if (orig_sock_table) {
75 static_key_slow_dec(&rps_needed);
76 synchronize_rcu();
77 vfree(orig_sock_table);
78 }
79 }
80 }
81
82 mutex_unlock(&sock_flow_mutex);
83
84 return ret;
85}
86#endif /* CONFIG_RPS */
87
88static struct ctl_table net_core_table[] = {
89#ifdef CONFIG_NET
90 {
91 .procname = "wmem_max",
92 .data = &sysctl_wmem_max,
93 .maxlen = sizeof(int),
94 .mode = 0644,
95 .proc_handler = proc_dointvec
96 },
97 {
98 .procname = "rmem_max",
99 .data = &sysctl_rmem_max,
100 .maxlen = sizeof(int),
101 .mode = 0644,
102 .proc_handler = proc_dointvec
103 },
104 {
105 .procname = "wmem_default",
106 .data = &sysctl_wmem_default,
107 .maxlen = sizeof(int),
108 .mode = 0644,
109 .proc_handler = proc_dointvec
110 },
111 {
112 .procname = "rmem_default",
113 .data = &sysctl_rmem_default,
114 .maxlen = sizeof(int),
115 .mode = 0644,
116 .proc_handler = proc_dointvec
117 },
118 {
119 .procname = "dev_weight",
120 .data = &weight_p,
121 .maxlen = sizeof(int),
122 .mode = 0644,
123 .proc_handler = proc_dointvec
124 },
125 {
126 .procname = "netdev_max_backlog",
127 .data = &netdev_max_backlog,
128 .maxlen = sizeof(int),
129 .mode = 0644,
130 .proc_handler = proc_dointvec
131 },
132#ifdef CONFIG_BPF_JIT
133 {
134 .procname = "bpf_jit_enable",
135 .data = &bpf_jit_enable,
136 .maxlen = sizeof(int),
137 .mode = 0644,
138 .proc_handler = proc_dointvec
139 },
140#endif
141 {
142 .procname = "netdev_tstamp_prequeue",
143 .data = &netdev_tstamp_prequeue,
144 .maxlen = sizeof(int),
145 .mode = 0644,
146 .proc_handler = proc_dointvec
147 },
148 {
149 .procname = "message_cost",
150 .data = &net_ratelimit_state.interval,
151 .maxlen = sizeof(int),
152 .mode = 0644,
153 .proc_handler = proc_dointvec_jiffies,
154 },
155 {
156 .procname = "message_burst",
157 .data = &net_ratelimit_state.burst,
158 .maxlen = sizeof(int),
159 .mode = 0644,
160 .proc_handler = proc_dointvec,
161 },
162 {
163 .procname = "optmem_max",
164 .data = &sysctl_optmem_max,
165 .maxlen = sizeof(int),
166 .mode = 0644,
167 .proc_handler = proc_dointvec
168 },
169#ifdef CONFIG_RPS
170 {
171 .procname = "rps_sock_flow_entries",
172 .maxlen = sizeof(int),
173 .mode = 0644,
174 .proc_handler = rps_sock_flow_sysctl
175 },
176#endif
177#endif /* CONFIG_NET */
178 {
179 .procname = "netdev_budget",
180 .data = &netdev_budget,
181 .maxlen = sizeof(int),
182 .mode = 0644,
183 .proc_handler = proc_dointvec
184 },
185 {
186 .procname = "warnings",
187 .data = &net_msg_warn,
188 .maxlen = sizeof(int),
189 .mode = 0644,
190 .proc_handler = proc_dointvec
191 },
192 { }
193};
194
195static struct ctl_table netns_core_table[] = {
196 {
197 .procname = "somaxconn",
198 .data = &init_net.core.sysctl_somaxconn,
199 .maxlen = sizeof(int),
200 .mode = 0644,
201 .proc_handler = proc_dointvec
202 },
203 { }
204};
205
206static __net_init int sysctl_core_net_init(struct net *net)
207{
208 struct ctl_table *tbl;
209
210 net->core.sysctl_somaxconn = SOMAXCONN;
211
212 tbl = netns_core_table;
213 if (!net_eq(net, &init_net)) {
214 tbl = kmemdup(tbl, sizeof(netns_core_table), GFP_KERNEL);
215 if (tbl == NULL)
216 goto err_dup;
217
218 tbl[0].data = &net->core.sysctl_somaxconn;
219 }
220
221 net->core.sysctl_hdr = register_net_sysctl(net, "net/core", tbl);
222 if (net->core.sysctl_hdr == NULL)
223 goto err_reg;
224
225 return 0;
226
227err_reg:
228 if (tbl != netns_core_table)
229 kfree(tbl);
230err_dup:
231 return -ENOMEM;
232}
233
234static __net_exit void sysctl_core_net_exit(struct net *net)
235{
236 struct ctl_table *tbl;
237
238 tbl = net->core.sysctl_hdr->ctl_table_arg;
239 unregister_net_sysctl_table(net->core.sysctl_hdr);
240 BUG_ON(tbl == netns_core_table);
241 kfree(tbl);
242}
243
244static __net_initdata struct pernet_operations sysctl_core_ops = {
245 .init = sysctl_core_net_init,
246 .exit = sysctl_core_net_exit,
247};
248
249static __init int sysctl_core_init(void)
250{
251 register_net_sysctl(&init_net, "net/core", net_core_table);
252 return register_pernet_subsys(&sysctl_core_ops);
253}
254
255fs_initcall(sysctl_core_init);