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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 "util.h"
17
18static void *get_ipc(struct ctl_table *table)
19{
20 char *which = table->data;
21 struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns;
22 which = (which - (char *)&init_ipc_ns) + (char *)ipc_ns;
23 return which;
24}
25
26static int proc_ipc_dointvec(struct ctl_table *table, int write,
27 void *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 *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 *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 *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 *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 *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
101
102 if (ret)
103 ns->sem_ctls[3] = semmni;
104 return ret;
105}
106
107#ifdef CONFIG_CHECKPOINT_RESTORE
108static int proc_ipc_dointvec_minmax_checkpoint_restore(struct ctl_table *table,
109 int write, void *buffer, size_t *lenp, loff_t *ppos)
110{
111 struct user_namespace *user_ns = current->nsproxy->ipc_ns->user_ns;
112
113 if (write && !checkpoint_restore_ns_capable(user_ns))
114 return -EPERM;
115
116 return proc_ipc_dointvec_minmax(table, write, buffer, lenp, ppos);
117}
118#endif
119
120int ipc_mni = IPCMNI;
121int ipc_mni_shift = IPCMNI_SHIFT;
122int ipc_min_cycle = RADIX_TREE_MAP_SIZE;
123
124static struct ctl_table ipc_kern_table[] = {
125 {
126 .procname = "shmmax",
127 .data = &init_ipc_ns.shm_ctlmax,
128 .maxlen = sizeof(init_ipc_ns.shm_ctlmax),
129 .mode = 0644,
130 .proc_handler = proc_ipc_doulongvec_minmax,
131 },
132 {
133 .procname = "shmall",
134 .data = &init_ipc_ns.shm_ctlall,
135 .maxlen = sizeof(init_ipc_ns.shm_ctlall),
136 .mode = 0644,
137 .proc_handler = proc_ipc_doulongvec_minmax,
138 },
139 {
140 .procname = "shmmni",
141 .data = &init_ipc_ns.shm_ctlmni,
142 .maxlen = sizeof(init_ipc_ns.shm_ctlmni),
143 .mode = 0644,
144 .proc_handler = proc_ipc_dointvec_minmax,
145 .extra1 = SYSCTL_ZERO,
146 .extra2 = &ipc_mni,
147 },
148 {
149 .procname = "shm_rmid_forced",
150 .data = &init_ipc_ns.shm_rmid_forced,
151 .maxlen = sizeof(init_ipc_ns.shm_rmid_forced),
152 .mode = 0644,
153 .proc_handler = proc_ipc_dointvec_minmax_orphans,
154 .extra1 = SYSCTL_ZERO,
155 .extra2 = SYSCTL_ONE,
156 },
157 {
158 .procname = "msgmax",
159 .data = &init_ipc_ns.msg_ctlmax,
160 .maxlen = sizeof(init_ipc_ns.msg_ctlmax),
161 .mode = 0644,
162 .proc_handler = proc_ipc_dointvec_minmax,
163 .extra1 = SYSCTL_ZERO,
164 .extra2 = SYSCTL_INT_MAX,
165 },
166 {
167 .procname = "msgmni",
168 .data = &init_ipc_ns.msg_ctlmni,
169 .maxlen = sizeof(init_ipc_ns.msg_ctlmni),
170 .mode = 0644,
171 .proc_handler = proc_ipc_dointvec_minmax,
172 .extra1 = SYSCTL_ZERO,
173 .extra2 = &ipc_mni,
174 },
175 {
176 .procname = "auto_msgmni",
177 .data = NULL,
178 .maxlen = sizeof(int),
179 .mode = 0644,
180 .proc_handler = proc_ipc_auto_msgmni,
181 .extra1 = SYSCTL_ZERO,
182 .extra2 = SYSCTL_ONE,
183 },
184 {
185 .procname = "msgmnb",
186 .data = &init_ipc_ns.msg_ctlmnb,
187 .maxlen = sizeof(init_ipc_ns.msg_ctlmnb),
188 .mode = 0644,
189 .proc_handler = proc_ipc_dointvec_minmax,
190 .extra1 = SYSCTL_ZERO,
191 .extra2 = SYSCTL_INT_MAX,
192 },
193 {
194 .procname = "sem",
195 .data = &init_ipc_ns.sem_ctls,
196 .maxlen = 4*sizeof(int),
197 .mode = 0644,
198 .proc_handler = proc_ipc_sem_dointvec,
199 },
200#ifdef CONFIG_CHECKPOINT_RESTORE
201 {
202 .procname = "sem_next_id",
203 .data = &init_ipc_ns.ids[IPC_SEM_IDS].next_id,
204 .maxlen = sizeof(init_ipc_ns.ids[IPC_SEM_IDS].next_id),
205 .mode = 0666,
206 .proc_handler = proc_ipc_dointvec_minmax_checkpoint_restore,
207 .extra1 = SYSCTL_ZERO,
208 .extra2 = SYSCTL_INT_MAX,
209 },
210 {
211 .procname = "msg_next_id",
212 .data = &init_ipc_ns.ids[IPC_MSG_IDS].next_id,
213 .maxlen = sizeof(init_ipc_ns.ids[IPC_MSG_IDS].next_id),
214 .mode = 0666,
215 .proc_handler = proc_ipc_dointvec_minmax_checkpoint_restore,
216 .extra1 = SYSCTL_ZERO,
217 .extra2 = SYSCTL_INT_MAX,
218 },
219 {
220 .procname = "shm_next_id",
221 .data = &init_ipc_ns.ids[IPC_SHM_IDS].next_id,
222 .maxlen = sizeof(init_ipc_ns.ids[IPC_SHM_IDS].next_id),
223 .mode = 0666,
224 .proc_handler = proc_ipc_dointvec_minmax_checkpoint_restore,
225 .extra1 = SYSCTL_ZERO,
226 .extra2 = SYSCTL_INT_MAX,
227 },
228#endif
229 {}
230};
231
232static struct ctl_table ipc_root_table[] = {
233 {
234 .procname = "kernel",
235 .mode = 0555,
236 .child = ipc_kern_table,
237 },
238 {}
239};
240
241static int __init ipc_sysctl_init(void)
242{
243 register_sysctl_table(ipc_root_table);
244 return 0;
245}
246
247device_initcall(ipc_sysctl_init);
248
249static int __init ipc_mni_extend(char *str)
250{
251 ipc_mni = IPCMNI_EXTEND;
252 ipc_mni_shift = IPCMNI_EXTEND_SHIFT;
253 ipc_min_cycle = IPCMNI_EXTEND_MIN_CYCLE;
254 pr_info("IPCMNI extended to %d.\n", ipc_mni);
255 return 0;
256}
257early_param("ipcmni_extend", ipc_mni_extend);
258