projects/linux·blob v5.2-rc1 · refs

260 lines · 6.2 KiB

1/*
2 * Copyright (C) 2007
3 *
4 * Author: Eric Biederman <[email protected]>
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License as
8 * published by the Free Software Foundation, version 2 of the
9 * License.
10 */
11
12#include <linux/module.h>
13#include <linux/ipc.h>
14#include <linux/nsproxy.h>
15#include <linux/sysctl.h>
16#include <linux/uaccess.h>
17#include <linux/ipc_namespace.h>
18#include <linux/msg.h>
19#include "util.h"
20
21static void *get_ipc(struct ctl_table *table)
22{
23 char *which = table->data;
24 struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns;
25 which = (which - (char *)&init_ipc_ns) + (char *)ipc_ns;
26 return which;
27}
28
29#ifdef CONFIG_PROC_SYSCTL
30static int proc_ipc_dointvec(struct ctl_table *table, int write,
31 void __user *buffer, size_t *lenp, loff_t *ppos)
32{
33 struct ctl_table ipc_table;
34
35 memcpy(&ipc_table, table, sizeof(ipc_table));
36 ipc_table.data = get_ipc(table);
37
38 return proc_dointvec(&ipc_table, write, buffer, lenp, ppos);
39}
40
41static int proc_ipc_dointvec_minmax(struct ctl_table *table, int write,
42 void __user *buffer, size_t *lenp, loff_t *ppos)
43{
44 struct ctl_table ipc_table;
45
46 memcpy(&ipc_table, table, sizeof(ipc_table));
47 ipc_table.data = get_ipc(table);
48
49 return proc_dointvec_minmax(&ipc_table, write, buffer, lenp, ppos);
50}
51
52static int proc_ipc_dointvec_minmax_orphans(struct ctl_table *table, int write,
53 void __user *buffer, size_t *lenp, loff_t *ppos)
54{
55 struct ipc_namespace *ns = current->nsproxy->ipc_ns;
56 int err = proc_ipc_dointvec_minmax(table, write, buffer, lenp, ppos);
57
58 if (err < 0)
59 return err;
60 if (ns->shm_rmid_forced)
61 shm_destroy_orphaned(ns);
62 return err;
63}
64
65static int proc_ipc_doulongvec_minmax(struct ctl_table *table, int write,
66 void __user *buffer, size_t *lenp, loff_t *ppos)
67{
68 struct ctl_table ipc_table;
69 memcpy(&ipc_table, table, sizeof(ipc_table));
70 ipc_table.data = get_ipc(table);
71
72 return proc_doulongvec_minmax(&ipc_table, write, buffer,
73 lenp, ppos);
74}
75
76static int proc_ipc_auto_msgmni(struct ctl_table *table, int write,
77 void __user *buffer, size_t *lenp, loff_t *ppos)
78{
79 struct ctl_table ipc_table;
80 int dummy = 0;
81
82 memcpy(&ipc_table, table, sizeof(ipc_table));
83 ipc_table.data = &dummy;
84
85 if (write)
86 pr_info_once("writing to auto_msgmni has no effect");
87
88 return proc_dointvec_minmax(&ipc_table, write, buffer, lenp, ppos);
89}
90
91static int proc_ipc_sem_dointvec(struct ctl_table *table, int write,
92 void __user *buffer, size_t *lenp, loff_t *ppos)
93{
94 int ret, semmni;
95 struct ipc_namespace *ns = current->nsproxy->ipc_ns;
96
97 semmni = ns->sem_ctls[3];
98 ret = proc_ipc_dointvec(table, write, buffer, lenp, ppos);
99
100 if (!ret)
101 ret = sem_check_semmni(current->nsproxy->ipc_ns);
102
103 /*
104 * Reset the semmni value if an error happens.
105 */
106 if (ret)
107 ns->sem_ctls[3] = semmni;
108 return ret;
109}
110
111#else
112#define proc_ipc_doulongvec_minmax NULL
113#define proc_ipc_dointvec NULL
114#define proc_ipc_dointvec_minmax NULL
115#define proc_ipc_dointvec_minmax_orphans NULL
116#define proc_ipc_auto_msgmni NULL
117#define proc_ipc_sem_dointvec NULL
118#endif
119
120static int zero;
121static int one = 1;
122static int int_max = INT_MAX;
123int ipc_mni = IPCMNI;
124int ipc_mni_shift = IPCMNI_SHIFT;
125int ipc_min_cycle = RADIX_TREE_MAP_SIZE;
126
127static struct ctl_table ipc_kern_table[] = {
128 {
129 .procname = "shmmax",
130 .data = &init_ipc_ns.shm_ctlmax,
131 .maxlen = sizeof(init_ipc_ns.shm_ctlmax),
132 .mode = 0644,
133 .proc_handler = proc_ipc_doulongvec_minmax,
134 },
135 {
136 .procname = "shmall",
137 .data = &init_ipc_ns.shm_ctlall,
138 .maxlen = sizeof(init_ipc_ns.shm_ctlall),
139 .mode = 0644,
140 .proc_handler = proc_ipc_doulongvec_minmax,
141 },
142 {
143 .procname = "shmmni",
144 .data = &init_ipc_ns.shm_ctlmni,
145 .maxlen = sizeof(init_ipc_ns.shm_ctlmni),
146 .mode = 0644,
147 .proc_handler = proc_ipc_dointvec_minmax,
148 .extra1 = &zero,
149 .extra2 = &ipc_mni,
150 },
151 {
152 .procname = "shm_rmid_forced",
153 .data = &init_ipc_ns.shm_rmid_forced,
154 .maxlen = sizeof(init_ipc_ns.shm_rmid_forced),
155 .mode = 0644,
156 .proc_handler = proc_ipc_dointvec_minmax_orphans,
157 .extra1 = &zero,
158 .extra2 = &one,
159 },
160 {
161 .procname = "msgmax",
162 .data = &init_ipc_ns.msg_ctlmax,
163 .maxlen = sizeof(init_ipc_ns.msg_ctlmax),
164 .mode = 0644,
165 .proc_handler = proc_ipc_dointvec_minmax,
166 .extra1 = &zero,
167 .extra2 = &int_max,
168 },
169 {
170 .procname = "msgmni",
171 .data = &init_ipc_ns.msg_ctlmni,
172 .maxlen = sizeof(init_ipc_ns.msg_ctlmni),
173 .mode = 0644,
174 .proc_handler = proc_ipc_dointvec_minmax,
175 .extra1 = &zero,
176 .extra2 = &ipc_mni,
177 },
178 {
179 .procname = "auto_msgmni",
180 .data = NULL,
181 .maxlen = sizeof(int),
182 .mode = 0644,
183 .proc_handler = proc_ipc_auto_msgmni,
184 .extra1 = &zero,
185 .extra2 = &one,
186 },
187 {
188 .procname = "msgmnb",
189 .data = &init_ipc_ns.msg_ctlmnb,
190 .maxlen = sizeof(init_ipc_ns.msg_ctlmnb),
191 .mode = 0644,
192 .proc_handler = proc_ipc_dointvec_minmax,
193 .extra1 = &zero,
194 .extra2 = &int_max,
195 },
196 {
197 .procname = "sem",
198 .data = &init_ipc_ns.sem_ctls,
199 .maxlen = 4*sizeof(int),
200 .mode = 0644,
201 .proc_handler = proc_ipc_sem_dointvec,
202 },
203#ifdef CONFIG_CHECKPOINT_RESTORE
204 {
205 .procname = "sem_next_id",
206 .data = &init_ipc_ns.ids[IPC_SEM_IDS].next_id,
207 .maxlen = sizeof(init_ipc_ns.ids[IPC_SEM_IDS].next_id),
208 .mode = 0644,
209 .proc_handler = proc_ipc_dointvec_minmax,
210 .extra1 = &zero,
211 .extra2 = &int_max,
212 },
213 {
214 .procname = "msg_next_id",
215 .data = &init_ipc_ns.ids[IPC_MSG_IDS].next_id,
216 .maxlen = sizeof(init_ipc_ns.ids[IPC_MSG_IDS].next_id),
217 .mode = 0644,
218 .proc_handler = proc_ipc_dointvec_minmax,
219 .extra1 = &zero,
220 .extra2 = &int_max,
221 },
222 {
223 .procname = "shm_next_id",
224 .data = &init_ipc_ns.ids[IPC_SHM_IDS].next_id,
225 .maxlen = sizeof(init_ipc_ns.ids[IPC_SHM_IDS].next_id),
226 .mode = 0644,
227 .proc_handler = proc_ipc_dointvec_minmax,
228 .extra1 = &zero,
229 .extra2 = &int_max,
230 },
231#endif
232 {}
233};
234
235static struct ctl_table ipc_root_table[] = {
236 {
237 .procname = "kernel",
238 .mode = 0555,
239 .child = ipc_kern_table,
240 },
241 {}
242};
243
244static int __init ipc_sysctl_init(void)
245{
246 register_sysctl_table(ipc_root_table);
247 return 0;
248}
249
250device_initcall(ipc_sysctl_init);
251
252static int __init ipc_mni_extend(char *str)
253{
254 ipc_mni = IPCMNI_EXTEND;
255 ipc_mni_shift = IPCMNI_EXTEND_SHIFT;
256 ipc_min_cycle = IPCMNI_EXTEND_MIN_CYCLE;
257 pr_info("IPCMNI extended to %d.\n", ipc_mni);
258 return 0;
259}
260early_param("ipcmni_extend", ipc_mni_extend);