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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2007
4 *
5 * Author: Eric Biederman <ebiederm@xmision.com>
6 */
7
8#include <linux/module.h>
9#include <linux/ipc.h>
10#include <linux/nsproxy.h>
11#include <linux/sysctl.h>
12#include <linux/uaccess.h>
13#include <linux/capability.h>
14#include <linux/ipc_namespace.h>
15#include <linux/msg.h>
16#include <linux/slab.h>
17#include "util.h"
18
19static int proc_ipc_dointvec_minmax_orphans(struct ctl_table *table, int write,
20 void *buffer, size_t *lenp, loff_t *ppos)
21{
22 struct ipc_namespace *ns =
23 container_of(table->data, struct ipc_namespace, shm_rmid_forced);
24 int err;
25
26 err = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
27
28 if (err < 0)
29 return err;
30 if (ns->shm_rmid_forced)
31 shm_destroy_orphaned(ns);
32 return err;
33}
34
35static int proc_ipc_auto_msgmni(struct ctl_table *table, int write,
36 void *buffer, size_t *lenp, loff_t *ppos)
37{
38 struct ctl_table ipc_table;
39 int dummy = 0;
40
41 memcpy(&ipc_table, table, sizeof(ipc_table));
42 ipc_table.data = &dummy;
43
44 if (write)
45 pr_info_once("writing to auto_msgmni has no effect");
46
47 return proc_dointvec_minmax(&ipc_table, write, buffer, lenp, ppos);
48}
49
50static int proc_ipc_sem_dointvec(struct ctl_table *table, int write,
51 void *buffer, size_t *lenp, loff_t *ppos)
52{
53 struct ipc_namespace *ns =
54 container_of(table->data, struct ipc_namespace, sem_ctls);
55 int ret, semmni;
56
57 semmni = ns->sem_ctls[3];
58 ret = proc_dointvec(table, write, buffer, lenp, ppos);
59
60 if (!ret)
61 ret = sem_check_semmni(ns);
62
63 /*
64 * Reset the semmni value if an error happens.
65 */
66 if (ret)
67 ns->sem_ctls[3] = semmni;
68 return ret;
69}
70
71int ipc_mni = IPCMNI;
72int ipc_mni_shift = IPCMNI_SHIFT;
73int ipc_min_cycle = RADIX_TREE_MAP_SIZE;
74
75static struct ctl_table ipc_sysctls[] = {
76 {
77 .procname = "shmmax",
78 .data = &init_ipc_ns.shm_ctlmax,
79 .maxlen = sizeof(init_ipc_ns.shm_ctlmax),
80 .mode = 0644,
81 .proc_handler = proc_doulongvec_minmax,
82 },
83 {
84 .procname = "shmall",
85 .data = &init_ipc_ns.shm_ctlall,
86 .maxlen = sizeof(init_ipc_ns.shm_ctlall),
87 .mode = 0644,
88 .proc_handler = proc_doulongvec_minmax,
89 },
90 {
91 .procname = "shmmni",
92 .data = &init_ipc_ns.shm_ctlmni,
93 .maxlen = sizeof(init_ipc_ns.shm_ctlmni),
94 .mode = 0644,
95 .proc_handler = proc_dointvec_minmax,
96 .extra1 = SYSCTL_ZERO,
97 .extra2 = &ipc_mni,
98 },
99 {
100 .procname = "shm_rmid_forced",
101 .data = &init_ipc_ns.shm_rmid_forced,
102 .maxlen = sizeof(init_ipc_ns.shm_rmid_forced),
103 .mode = 0644,
104 .proc_handler = proc_ipc_dointvec_minmax_orphans,
105 .extra1 = SYSCTL_ZERO,
106 .extra2 = SYSCTL_ONE,
107 },
108 {
109 .procname = "msgmax",
110 .data = &init_ipc_ns.msg_ctlmax,
111 .maxlen = sizeof(init_ipc_ns.msg_ctlmax),
112 .mode = 0644,
113 .proc_handler = proc_dointvec_minmax,
114 .extra1 = SYSCTL_ZERO,
115 .extra2 = SYSCTL_INT_MAX,
116 },
117 {
118 .procname = "msgmni",
119 .data = &init_ipc_ns.msg_ctlmni,
120 .maxlen = sizeof(init_ipc_ns.msg_ctlmni),
121 .mode = 0644,
122 .proc_handler = proc_dointvec_minmax,
123 .extra1 = SYSCTL_ZERO,
124 .extra2 = &ipc_mni,
125 },
126 {
127 .procname = "auto_msgmni",
128 .data = NULL,
129 .maxlen = sizeof(int),
130 .mode = 0644,
131 .proc_handler = proc_ipc_auto_msgmni,
132 .extra1 = SYSCTL_ZERO,
133 .extra2 = SYSCTL_ONE,
134 },
135 {
136 .procname = "msgmnb",
137 .data = &init_ipc_ns.msg_ctlmnb,
138 .maxlen = sizeof(init_ipc_ns.msg_ctlmnb),
139 .mode = 0644,
140 .proc_handler = proc_dointvec_minmax,
141 .extra1 = SYSCTL_ZERO,
142 .extra2 = SYSCTL_INT_MAX,
143 },
144 {
145 .procname = "sem",
146 .data = &init_ipc_ns.sem_ctls,
147 .maxlen = 4*sizeof(int),
148 .mode = 0644,
149 .proc_handler = proc_ipc_sem_dointvec,
150 },
151#ifdef CONFIG_CHECKPOINT_RESTORE
152 {
153 .procname = "sem_next_id",
154 .data = &init_ipc_ns.ids[IPC_SEM_IDS].next_id,
155 .maxlen = sizeof(init_ipc_ns.ids[IPC_SEM_IDS].next_id),
156 .mode = 0444,
157 .proc_handler = proc_dointvec_minmax,
158 .extra1 = SYSCTL_ZERO,
159 .extra2 = SYSCTL_INT_MAX,
160 },
161 {
162 .procname = "msg_next_id",
163 .data = &init_ipc_ns.ids[IPC_MSG_IDS].next_id,
164 .maxlen = sizeof(init_ipc_ns.ids[IPC_MSG_IDS].next_id),
165 .mode = 0444,
166 .proc_handler = proc_dointvec_minmax,
167 .extra1 = SYSCTL_ZERO,
168 .extra2 = SYSCTL_INT_MAX,
169 },
170 {
171 .procname = "shm_next_id",
172 .data = &init_ipc_ns.ids[IPC_SHM_IDS].next_id,
173 .maxlen = sizeof(init_ipc_ns.ids[IPC_SHM_IDS].next_id),
174 .mode = 0444,
175 .proc_handler = proc_dointvec_minmax,
176 .extra1 = SYSCTL_ZERO,
177 .extra2 = SYSCTL_INT_MAX,
178 },
179#endif
180 {}
181};
182
183static struct ctl_table_set *set_lookup(struct ctl_table_root *root)
184{
185 return ¤t->nsproxy->ipc_ns->ipc_set;
186}
187
188static int set_is_seen(struct ctl_table_set *set)
189{
190 return ¤t->nsproxy->ipc_ns->ipc_set == set;
191}
192
193static int ipc_permissions(struct ctl_table_header *head, struct ctl_table *table)
194{
195 int mode = table->mode;
196
197#ifdef CONFIG_CHECKPOINT_RESTORE
198 struct ipc_namespace *ns = current->nsproxy->ipc_ns;
199
200 if (((table->data == &ns->ids[IPC_SEM_IDS].next_id) ||
201 (table->data == &ns->ids[IPC_MSG_IDS].next_id) ||
202 (table->data == &ns->ids[IPC_SHM_IDS].next_id)) &&
203 checkpoint_restore_ns_capable(ns->user_ns))
204 mode = 0666;
205#endif
206 return mode;
207}
208
209static struct ctl_table_root set_root = {
210 .lookup = set_lookup,
211 .permissions = ipc_permissions,
212};
213
214bool setup_ipc_sysctls(struct ipc_namespace *ns)
215{
216 struct ctl_table *tbl;
217
218 setup_sysctl_set(&ns->ipc_set, &set_root, set_is_seen);
219
220 tbl = kmemdup(ipc_sysctls, sizeof(ipc_sysctls), GFP_KERNEL);
221 if (tbl) {
222 int i;
223
224 for (i = 0; i < ARRAY_SIZE(ipc_sysctls); i++) {
225 if (tbl[i].data == &init_ipc_ns.shm_ctlmax)
226 tbl[i].data = &ns->shm_ctlmax;
227
228 else if (tbl[i].data == &init_ipc_ns.shm_ctlall)
229 tbl[i].data = &ns->shm_ctlall;
230
231 else if (tbl[i].data == &init_ipc_ns.shm_ctlmni)
232 tbl[i].data = &ns->shm_ctlmni;
233
234 else if (tbl[i].data == &init_ipc_ns.shm_rmid_forced)
235 tbl[i].data = &ns->shm_rmid_forced;
236
237 else if (tbl[i].data == &init_ipc_ns.msg_ctlmax)
238 tbl[i].data = &ns->msg_ctlmax;
239
240 else if (tbl[i].data == &init_ipc_ns.msg_ctlmni)
241 tbl[i].data = &ns->msg_ctlmni;
242
243 else if (tbl[i].data == &init_ipc_ns.msg_ctlmnb)
244 tbl[i].data = &ns->msg_ctlmnb;
245
246 else if (tbl[i].data == &init_ipc_ns.sem_ctls)
247 tbl[i].data = &ns->sem_ctls;
248#ifdef CONFIG_CHECKPOINT_RESTORE
249 else if (tbl[i].data == &init_ipc_ns.ids[IPC_SEM_IDS].next_id)
250 tbl[i].data = &ns->ids[IPC_SEM_IDS].next_id;
251
252 else if (tbl[i].data == &init_ipc_ns.ids[IPC_MSG_IDS].next_id)
253 tbl[i].data = &ns->ids[IPC_MSG_IDS].next_id;
254
255 else if (tbl[i].data == &init_ipc_ns.ids[IPC_SHM_IDS].next_id)
256 tbl[i].data = &ns->ids[IPC_SHM_IDS].next_id;
257#endif
258 else
259 tbl[i].data = NULL;
260 }
261
262 ns->ipc_sysctls = __register_sysctl_table(&ns->ipc_set, "kernel", tbl);
263 }
264 if (!ns->ipc_sysctls) {
265 kfree(tbl);
266 retire_sysctl_set(&ns->ipc_set);
267 return false;
268 }
269
270 return true;
271}
272
273void retire_ipc_sysctls(struct ipc_namespace *ns)
274{
275 struct ctl_table *tbl;
276
277 tbl = ns->ipc_sysctls->ctl_table_arg;
278 unregister_sysctl_table(ns->ipc_sysctls);
279 retire_sysctl_set(&ns->ipc_set);
280 kfree(tbl);
281}
282
283static int __init ipc_sysctl_init(void)
284{
285 if (!setup_ipc_sysctls(&init_ipc_ns)) {
286 pr_warn("ipc sysctl registration failed\n");
287 return -ENOMEM;
288 }
289 return 0;
290}
291
292device_initcall(ipc_sysctl_init);
293
294static int __init ipc_mni_extend(char *str)
295{
296 ipc_mni = IPCMNI_EXTEND;
297 ipc_mni_shift = IPCMNI_EXTEND_SHIFT;
298 ipc_min_cycle = IPCMNI_EXTEND_MIN_CYCLE;
299 pr_info("IPCMNI extended to %d.\n", ipc_mni);
300 return 0;
301}
302early_param("ipcmni_extend", ipc_mni_extend);
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2007
4 *
5 * Author: Eric Biederman <ebiederm@xmision.com>
6 */
7
8#include <linux/module.h>
9#include <linux/ipc.h>
10#include <linux/nsproxy.h>
11#include <linux/sysctl.h>
12#include <linux/uaccess.h>
13#include <linux/ipc_namespace.h>
14#include <linux/msg.h>
15#include "util.h"
16
17static void *get_ipc(struct ctl_table *table)
18{
19 char *which = table->data;
20 struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns;
21 which = (which - (char *)&init_ipc_ns) + (char *)ipc_ns;
22 return which;
23}
24
25#ifdef CONFIG_PROC_SYSCTL
26static int proc_ipc_dointvec(struct ctl_table *table, int write,
27 void __user *buffer, size_t *lenp, loff_t *ppos)
28{
29 struct ctl_table ipc_table;
30
31 memcpy(&ipc_table, table, sizeof(ipc_table));
32 ipc_table.data = get_ipc(table);
33
34 return proc_dointvec(&ipc_table, write, buffer, lenp, ppos);
35}
36
37static int proc_ipc_dointvec_minmax(struct ctl_table *table, int write,
38 void __user *buffer, size_t *lenp, loff_t *ppos)
39{
40 struct ctl_table ipc_table;
41
42 memcpy(&ipc_table, table, sizeof(ipc_table));
43 ipc_table.data = get_ipc(table);
44
45 return proc_dointvec_minmax(&ipc_table, write, buffer, lenp, ppos);
46}
47
48static int proc_ipc_dointvec_minmax_orphans(struct ctl_table *table, int write,
49 void __user *buffer, size_t *lenp, loff_t *ppos)
50{
51 struct ipc_namespace *ns = current->nsproxy->ipc_ns;
52 int err = proc_ipc_dointvec_minmax(table, write, buffer, lenp, ppos);
53
54 if (err < 0)
55 return err;
56 if (ns->shm_rmid_forced)
57 shm_destroy_orphaned(ns);
58 return err;
59}
60
61static int proc_ipc_doulongvec_minmax(struct ctl_table *table, int write,
62 void __user *buffer, size_t *lenp, loff_t *ppos)
63{
64 struct ctl_table ipc_table;
65 memcpy(&ipc_table, table, sizeof(ipc_table));
66 ipc_table.data = get_ipc(table);
67
68 return proc_doulongvec_minmax(&ipc_table, write, buffer,
69 lenp, ppos);
70}
71
72static int proc_ipc_auto_msgmni(struct ctl_table *table, int write,
73 void __user *buffer, size_t *lenp, loff_t *ppos)
74{
75 struct ctl_table ipc_table;
76 int dummy = 0;
77
78 memcpy(&ipc_table, table, sizeof(ipc_table));
79 ipc_table.data = &dummy;
80
81 if (write)
82 pr_info_once("writing to auto_msgmni has no effect");
83
84 return proc_dointvec_minmax(&ipc_table, write, buffer, lenp, ppos);
85}
86
87static int proc_ipc_sem_dointvec(struct ctl_table *table, int write,
88 void __user *buffer, size_t *lenp, loff_t *ppos)
89{
90 int ret, semmni;
91 struct ipc_namespace *ns = current->nsproxy->ipc_ns;
92
93 semmni = ns->sem_ctls[3];
94 ret = proc_ipc_dointvec(table, write, buffer, lenp, ppos);
95
96 if (!ret)
97 ret = sem_check_semmni(current->nsproxy->ipc_ns);
98
99 /*
100 * Reset the semmni value if an error happens.
101 */
102 if (ret)
103 ns->sem_ctls[3] = semmni;
104 return ret;
105}
106
107#else
108#define proc_ipc_doulongvec_minmax NULL
109#define proc_ipc_dointvec NULL
110#define proc_ipc_dointvec_minmax NULL
111#define proc_ipc_dointvec_minmax_orphans NULL
112#define proc_ipc_auto_msgmni NULL
113#define proc_ipc_sem_dointvec NULL
114#endif
115
116int ipc_mni = IPCMNI;
117int ipc_mni_shift = IPCMNI_SHIFT;
118int ipc_min_cycle = RADIX_TREE_MAP_SIZE;
119
120static struct ctl_table ipc_kern_table[] = {
121 {
122 .procname = "shmmax",
123 .data = &init_ipc_ns.shm_ctlmax,
124 .maxlen = sizeof(init_ipc_ns.shm_ctlmax),
125 .mode = 0644,
126 .proc_handler = proc_ipc_doulongvec_minmax,
127 },
128 {
129 .procname = "shmall",
130 .data = &init_ipc_ns.shm_ctlall,
131 .maxlen = sizeof(init_ipc_ns.shm_ctlall),
132 .mode = 0644,
133 .proc_handler = proc_ipc_doulongvec_minmax,
134 },
135 {
136 .procname = "shmmni",
137 .data = &init_ipc_ns.shm_ctlmni,
138 .maxlen = sizeof(init_ipc_ns.shm_ctlmni),
139 .mode = 0644,
140 .proc_handler = proc_ipc_dointvec_minmax,
141 .extra1 = SYSCTL_ZERO,
142 .extra2 = &ipc_mni,
143 },
144 {
145 .procname = "shm_rmid_forced",
146 .data = &init_ipc_ns.shm_rmid_forced,
147 .maxlen = sizeof(init_ipc_ns.shm_rmid_forced),
148 .mode = 0644,
149 .proc_handler = proc_ipc_dointvec_minmax_orphans,
150 .extra1 = SYSCTL_ZERO,
151 .extra2 = SYSCTL_ONE,
152 },
153 {
154 .procname = "msgmax",
155 .data = &init_ipc_ns.msg_ctlmax,
156 .maxlen = sizeof(init_ipc_ns.msg_ctlmax),
157 .mode = 0644,
158 .proc_handler = proc_ipc_dointvec_minmax,
159 .extra1 = SYSCTL_ZERO,
160 .extra2 = SYSCTL_INT_MAX,
161 },
162 {
163 .procname = "msgmni",
164 .data = &init_ipc_ns.msg_ctlmni,
165 .maxlen = sizeof(init_ipc_ns.msg_ctlmni),
166 .mode = 0644,
167 .proc_handler = proc_ipc_dointvec_minmax,
168 .extra1 = SYSCTL_ZERO,
169 .extra2 = &ipc_mni,
170 },
171 {
172 .procname = "auto_msgmni",
173 .data = NULL,
174 .maxlen = sizeof(int),
175 .mode = 0644,
176 .proc_handler = proc_ipc_auto_msgmni,
177 .extra1 = SYSCTL_ZERO,
178 .extra2 = SYSCTL_ONE,
179 },
180 {
181 .procname = "msgmnb",
182 .data = &init_ipc_ns.msg_ctlmnb,
183 .maxlen = sizeof(init_ipc_ns.msg_ctlmnb),
184 .mode = 0644,
185 .proc_handler = proc_ipc_dointvec_minmax,
186 .extra1 = SYSCTL_ZERO,
187 .extra2 = SYSCTL_INT_MAX,
188 },
189 {
190 .procname = "sem",
191 .data = &init_ipc_ns.sem_ctls,
192 .maxlen = 4*sizeof(int),
193 .mode = 0644,
194 .proc_handler = proc_ipc_sem_dointvec,
195 },
196#ifdef CONFIG_CHECKPOINT_RESTORE
197 {
198 .procname = "sem_next_id",
199 .data = &init_ipc_ns.ids[IPC_SEM_IDS].next_id,
200 .maxlen = sizeof(init_ipc_ns.ids[IPC_SEM_IDS].next_id),
201 .mode = 0644,
202 .proc_handler = proc_ipc_dointvec_minmax,
203 .extra1 = SYSCTL_ZERO,
204 .extra2 = SYSCTL_INT_MAX,
205 },
206 {
207 .procname = "msg_next_id",
208 .data = &init_ipc_ns.ids[IPC_MSG_IDS].next_id,
209 .maxlen = sizeof(init_ipc_ns.ids[IPC_MSG_IDS].next_id),
210 .mode = 0644,
211 .proc_handler = proc_ipc_dointvec_minmax,
212 .extra1 = SYSCTL_ZERO,
213 .extra2 = SYSCTL_INT_MAX,
214 },
215 {
216 .procname = "shm_next_id",
217 .data = &init_ipc_ns.ids[IPC_SHM_IDS].next_id,
218 .maxlen = sizeof(init_ipc_ns.ids[IPC_SHM_IDS].next_id),
219 .mode = 0644,
220 .proc_handler = proc_ipc_dointvec_minmax,
221 .extra1 = SYSCTL_ZERO,
222 .extra2 = SYSCTL_INT_MAX,
223 },
224#endif
225 {}
226};
227
228static struct ctl_table ipc_root_table[] = {
229 {
230 .procname = "kernel",
231 .mode = 0555,
232 .child = ipc_kern_table,
233 },
234 {}
235};
236
237static int __init ipc_sysctl_init(void)
238{
239 register_sysctl_table(ipc_root_table);
240 return 0;
241}
242
243device_initcall(ipc_sysctl_init);
244
245static int __init ipc_mni_extend(char *str)
246{
247 ipc_mni = IPCMNI_EXTEND;
248 ipc_mni_shift = IPCMNI_EXTEND_SHIFT;
249 ipc_min_cycle = IPCMNI_EXTEND_MIN_CYCLE;
250 pr_info("IPCMNI extended to %d.\n", ipc_mni);
251 return 0;
252}
253early_param("ipcmni_extend", ipc_mni_extend);