1 /*
2 * Copyright (C) 2007
3 *
4 * Author: Eric Biederman <ebiederm@xmision.com>
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
get_ipc(struct ctl_table * table)21 static 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
proc_ipc_dointvec(struct ctl_table * table,int write,void __user * buffer,size_t * lenp,loff_t * ppos)30 static 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
proc_ipc_dointvec_minmax(struct ctl_table * table,int write,void __user * buffer,size_t * lenp,loff_t * ppos)41 static 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
proc_ipc_dointvec_minmax_orphans(struct ctl_table * table,int write,void __user * buffer,size_t * lenp,loff_t * ppos)52 static 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
proc_ipc_doulongvec_minmax(struct ctl_table * table,int write,void __user * buffer,size_t * lenp,loff_t * ppos)65 static 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
proc_ipc_auto_msgmni(struct ctl_table * table,int write,void __user * buffer,size_t * lenp,loff_t * ppos)76 static 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
91 #else
92 #define proc_ipc_doulongvec_minmax NULL
93 #define proc_ipc_dointvec NULL
94 #define proc_ipc_dointvec_minmax NULL
95 #define proc_ipc_dointvec_minmax_orphans NULL
96 #define proc_ipc_auto_msgmni NULL
97 #endif
98
99 static int zero;
100 static int one = 1;
101 static int int_max = INT_MAX;
102
103 static struct ctl_table ipc_kern_table[] = {
104 {
105 .procname = "shmmax",
106 .data = &init_ipc_ns.shm_ctlmax,
107 .maxlen = sizeof(init_ipc_ns.shm_ctlmax),
108 .mode = 0644,
109 .proc_handler = proc_ipc_doulongvec_minmax,
110 },
111 {
112 .procname = "shmall",
113 .data = &init_ipc_ns.shm_ctlall,
114 .maxlen = sizeof(init_ipc_ns.shm_ctlall),
115 .mode = 0644,
116 .proc_handler = proc_ipc_doulongvec_minmax,
117 },
118 {
119 .procname = "shmmni",
120 .data = &init_ipc_ns.shm_ctlmni,
121 .maxlen = sizeof(init_ipc_ns.shm_ctlmni),
122 .mode = 0644,
123 .proc_handler = proc_ipc_dointvec,
124 },
125 {
126 .procname = "shm_rmid_forced",
127 .data = &init_ipc_ns.shm_rmid_forced,
128 .maxlen = sizeof(init_ipc_ns.shm_rmid_forced),
129 .mode = 0644,
130 .proc_handler = proc_ipc_dointvec_minmax_orphans,
131 .extra1 = &zero,
132 .extra2 = &one,
133 },
134 {
135 .procname = "msgmax",
136 .data = &init_ipc_ns.msg_ctlmax,
137 .maxlen = sizeof(init_ipc_ns.msg_ctlmax),
138 .mode = 0644,
139 .proc_handler = proc_ipc_dointvec_minmax,
140 .extra1 = &zero,
141 .extra2 = &int_max,
142 },
143 {
144 .procname = "msgmni",
145 .data = &init_ipc_ns.msg_ctlmni,
146 .maxlen = sizeof(init_ipc_ns.msg_ctlmni),
147 .mode = 0644,
148 .proc_handler = proc_ipc_dointvec_minmax,
149 .extra1 = &zero,
150 .extra2 = &int_max,
151 },
152 {
153 .procname = "auto_msgmni",
154 .data = NULL,
155 .maxlen = sizeof(int),
156 .mode = 0644,
157 .proc_handler = proc_ipc_auto_msgmni,
158 .extra1 = &zero,
159 .extra2 = &one,
160 },
161 {
162 .procname = "msgmnb",
163 .data = &init_ipc_ns.msg_ctlmnb,
164 .maxlen = sizeof(init_ipc_ns.msg_ctlmnb),
165 .mode = 0644,
166 .proc_handler = proc_ipc_dointvec_minmax,
167 .extra1 = &zero,
168 .extra2 = &int_max,
169 },
170 {
171 .procname = "sem",
172 .data = &init_ipc_ns.sem_ctls,
173 .maxlen = 4*sizeof(int),
174 .mode = 0644,
175 .proc_handler = proc_ipc_dointvec,
176 },
177 #ifdef CONFIG_CHECKPOINT_RESTORE
178 {
179 .procname = "sem_next_id",
180 .data = &init_ipc_ns.ids[IPC_SEM_IDS].next_id,
181 .maxlen = sizeof(init_ipc_ns.ids[IPC_SEM_IDS].next_id),
182 .mode = 0644,
183 .proc_handler = proc_ipc_dointvec_minmax,
184 .extra1 = &zero,
185 .extra2 = &int_max,
186 },
187 {
188 .procname = "msg_next_id",
189 .data = &init_ipc_ns.ids[IPC_MSG_IDS].next_id,
190 .maxlen = sizeof(init_ipc_ns.ids[IPC_MSG_IDS].next_id),
191 .mode = 0644,
192 .proc_handler = proc_ipc_dointvec_minmax,
193 .extra1 = &zero,
194 .extra2 = &int_max,
195 },
196 {
197 .procname = "shm_next_id",
198 .data = &init_ipc_ns.ids[IPC_SHM_IDS].next_id,
199 .maxlen = sizeof(init_ipc_ns.ids[IPC_SHM_IDS].next_id),
200 .mode = 0644,
201 .proc_handler = proc_ipc_dointvec_minmax,
202 .extra1 = &zero,
203 .extra2 = &int_max,
204 },
205 #endif
206 {}
207 };
208
209 static struct ctl_table ipc_root_table[] = {
210 {
211 .procname = "kernel",
212 .mode = 0555,
213 .child = ipc_kern_table,
214 },
215 {}
216 };
217
ipc_sysctl_init(void)218 static int __init ipc_sysctl_init(void)
219 {
220 register_sysctl_table(ipc_root_table);
221 return 0;
222 }
223
224 device_initcall(ipc_sysctl_init);
225
