tools/testing/selftests/sysctl/sysctl.sh: remove superfluous test_reqs()
[sfrench/cifs-2.6.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 static 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
120 static int zero;
121 static int one = 1;
122 static int int_max = INT_MAX;
123 static int ipc_mni = IPCMNI;
124
125 static struct ctl_table ipc_kern_table[] = {
126         {
127                 .procname       = "shmmax",
128                 .data           = &init_ipc_ns.shm_ctlmax,
129                 .maxlen         = sizeof(init_ipc_ns.shm_ctlmax),
130                 .mode           = 0644,
131                 .proc_handler   = proc_ipc_doulongvec_minmax,
132         },
133         {
134                 .procname       = "shmall",
135                 .data           = &init_ipc_ns.shm_ctlall,
136                 .maxlen         = sizeof(init_ipc_ns.shm_ctlall),
137                 .mode           = 0644,
138                 .proc_handler   = proc_ipc_doulongvec_minmax,
139         },
140         {
141                 .procname       = "shmmni",
142                 .data           = &init_ipc_ns.shm_ctlmni,
143                 .maxlen         = sizeof(init_ipc_ns.shm_ctlmni),
144                 .mode           = 0644,
145                 .proc_handler   = proc_ipc_dointvec_minmax,
146                 .extra1         = &zero,
147                 .extra2         = &ipc_mni,
148         },
149         {
150                 .procname       = "shm_rmid_forced",
151                 .data           = &init_ipc_ns.shm_rmid_forced,
152                 .maxlen         = sizeof(init_ipc_ns.shm_rmid_forced),
153                 .mode           = 0644,
154                 .proc_handler   = proc_ipc_dointvec_minmax_orphans,
155                 .extra1         = &zero,
156                 .extra2         = &one,
157         },
158         {
159                 .procname       = "msgmax",
160                 .data           = &init_ipc_ns.msg_ctlmax,
161                 .maxlen         = sizeof(init_ipc_ns.msg_ctlmax),
162                 .mode           = 0644,
163                 .proc_handler   = proc_ipc_dointvec_minmax,
164                 .extra1         = &zero,
165                 .extra2         = &int_max,
166         },
167         {
168                 .procname       = "msgmni",
169                 .data           = &init_ipc_ns.msg_ctlmni,
170                 .maxlen         = sizeof(init_ipc_ns.msg_ctlmni),
171                 .mode           = 0644,
172                 .proc_handler   = proc_ipc_dointvec_minmax,
173                 .extra1         = &zero,
174                 .extra2         = &ipc_mni,
175         },
176         {
177                 .procname       = "auto_msgmni",
178                 .data           = NULL,
179                 .maxlen         = sizeof(int),
180                 .mode           = 0644,
181                 .proc_handler   = proc_ipc_auto_msgmni,
182                 .extra1         = &zero,
183                 .extra2         = &one,
184         },
185         {
186                 .procname       =  "msgmnb",
187                 .data           = &init_ipc_ns.msg_ctlmnb,
188                 .maxlen         = sizeof(init_ipc_ns.msg_ctlmnb),
189                 .mode           = 0644,
190                 .proc_handler   = proc_ipc_dointvec_minmax,
191                 .extra1         = &zero,
192                 .extra2         = &int_max,
193         },
194         {
195                 .procname       = "sem",
196                 .data           = &init_ipc_ns.sem_ctls,
197                 .maxlen         = 4*sizeof(int),
198                 .mode           = 0644,
199                 .proc_handler   = proc_ipc_sem_dointvec,
200         },
201 #ifdef CONFIG_CHECKPOINT_RESTORE
202         {
203                 .procname       = "sem_next_id",
204                 .data           = &init_ipc_ns.ids[IPC_SEM_IDS].next_id,
205                 .maxlen         = sizeof(init_ipc_ns.ids[IPC_SEM_IDS].next_id),
206                 .mode           = 0644,
207                 .proc_handler   = proc_ipc_dointvec_minmax,
208                 .extra1         = &zero,
209                 .extra2         = &int_max,
210         },
211         {
212                 .procname       = "msg_next_id",
213                 .data           = &init_ipc_ns.ids[IPC_MSG_IDS].next_id,
214                 .maxlen         = sizeof(init_ipc_ns.ids[IPC_MSG_IDS].next_id),
215                 .mode           = 0644,
216                 .proc_handler   = proc_ipc_dointvec_minmax,
217                 .extra1         = &zero,
218                 .extra2         = &int_max,
219         },
220         {
221                 .procname       = "shm_next_id",
222                 .data           = &init_ipc_ns.ids[IPC_SHM_IDS].next_id,
223                 .maxlen         = sizeof(init_ipc_ns.ids[IPC_SHM_IDS].next_id),
224                 .mode           = 0644,
225                 .proc_handler   = proc_ipc_dointvec_minmax,
226                 .extra1         = &zero,
227                 .extra2         = &int_max,
228         },
229 #endif
230         {}
231 };
232
233 static struct ctl_table ipc_root_table[] = {
234         {
235                 .procname       = "kernel",
236                 .mode           = 0555,
237                 .child          = ipc_kern_table,
238         },
239         {}
240 };
241
242 static int __init ipc_sysctl_init(void)
243 {
244         register_sysctl_table(ipc_root_table);
245         return 0;
246 }
247
248 device_initcall(ipc_sysctl_init);