Merge tag 'ecryptfs-3.19-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel...
[platform/kernel/linux-rpi.git] / ipc / ipc_sysctl.c
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
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
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
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
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
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
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
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);