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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
18#ifdef CONFIG_IPC_NS
19static void *get_ipc(ctl_table *table)
20{
21 char *which = table->data;
22 struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns;
23 which = (which - (char *)&init_ipc_ns) + (char *)ipc_ns;
24 return which;
25}
26#else
27#define get_ipc(T) ((T)->data)
28#endif
29
30#ifdef CONFIG_PROC_FS
31static int proc_ipc_dointvec(ctl_table *table, int write, struct file *filp,
32 void __user *buffer, size_t *lenp, loff_t *ppos)
33{
34 struct ctl_table ipc_table;
35 memcpy(&ipc_table, table, sizeof(ipc_table));
36 ipc_table.data = get_ipc(table);
37
38 return proc_dointvec(&ipc_table, write, filp, buffer, lenp, ppos);
39}
40
41static int proc_ipc_doulongvec_minmax(ctl_table *table, int write,
42 struct file *filp, void __user *buffer, size_t *lenp, loff_t *ppos)
43{
44 struct ctl_table ipc_table;
45 memcpy(&ipc_table, table, sizeof(ipc_table));
46 ipc_table.data = get_ipc(table);
47
48 return proc_doulongvec_minmax(&ipc_table, write, filp, buffer,
49 lenp, ppos);
50}
51
52#else
53#define proc_ipc_doulongvec_minmax NULL
54#define proc_ipc_dointvec NULL
55#endif
56
57#ifdef CONFIG_SYSCTL_SYSCALL
58
59static int sysctl_ipc_data(ctl_table *table, int __user *name, int nlen,
60 void __user *oldval, size_t __user *oldlenp,
61 void __user *newval, size_t newlen)
62{
63 size_t len;
64 void *data;
65
66
67 if (!table->data || !table->maxlen)
68 return -ENOTDIR;
69
70 data = get_ipc(table);
71 if (!data)
72 return -ENOTDIR;
73
74 if (oldval && oldlenp) {
75 if (get_user(len, oldlenp))
76 return -EFAULT;
77 if (len) {
78 if (len > table->maxlen)
79 len = table->maxlen;
80 if (copy_to_user(oldval, data, len))
81 return -EFAULT;
82 if (put_user(len, oldlenp))
83 return -EFAULT;
84 }
85 }
86
87 if (newval && newlen) {
88 if (newlen > table->maxlen)
89 newlen = table->maxlen;
90
91 if (copy_from_user(data, newval, newlen))
92 return -EFAULT;
93 }
94 return 1;
95}
96#else
97#define sysctl_ipc_data NULL
98#endif
99
100static struct ctl_table ipc_kern_table[] = {
101 {
102 .ctl_name = KERN_SHMMAX,
103 .procname = "shmmax",
104 .data = &init_ipc_ns.shm_ctlmax,
105 .maxlen = sizeof (init_ipc_ns.shm_ctlmax),
106 .mode = 0644,
107 .proc_handler = proc_ipc_doulongvec_minmax,
108 .strategy = sysctl_ipc_data,
109 },
110 {
111 .ctl_name = KERN_SHMALL,
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 .strategy = sysctl_ipc_data,
118 },
119 {
120 .ctl_name = KERN_SHMMNI,
121 .procname = "shmmni",
122 .data = &init_ipc_ns.shm_ctlmni,
123 .maxlen = sizeof (init_ipc_ns.shm_ctlmni),
124 .mode = 0644,
125 .proc_handler = proc_ipc_dointvec,
126 .strategy = sysctl_ipc_data,
127 },
128 {
129 .ctl_name = KERN_MSGMAX,
130 .procname = "msgmax",
131 .data = &init_ipc_ns.msg_ctlmax,
132 .maxlen = sizeof (init_ipc_ns.msg_ctlmax),
133 .mode = 0644,
134 .proc_handler = proc_ipc_dointvec,
135 .strategy = sysctl_ipc_data,
136 },
137 {
138 .ctl_name = KERN_MSGMNI,
139 .procname = "msgmni",
140 .data = &init_ipc_ns.msg_ctlmni,
141 .maxlen = sizeof (init_ipc_ns.msg_ctlmni),
142 .mode = 0644,
143 .proc_handler = proc_ipc_dointvec,
144 .strategy = sysctl_ipc_data,
145 },
146 {
147 .ctl_name = KERN_MSGMNB,
148 .procname = "msgmnb",
149 .data = &init_ipc_ns.msg_ctlmnb,
150 .maxlen = sizeof (init_ipc_ns.msg_ctlmnb),
151 .mode = 0644,
152 .proc_handler = proc_ipc_dointvec,
153 .strategy = sysctl_ipc_data,
154 },
155 {
156 .ctl_name = KERN_SEM,
157 .procname = "sem",
158 .data = &init_ipc_ns.sem_ctls,
159 .maxlen = 4*sizeof (int),
160 .mode = 0644,
161 .proc_handler = proc_ipc_dointvec,
162 .strategy = sysctl_ipc_data,
163 },
164 {}
165};
166
167static struct ctl_table ipc_root_table[] = {
168 {
169 .ctl_name = CTL_KERN,
170 .procname = "kernel",
171 .mode = 0555,
172 .child = ipc_kern_table,
173 },
174 {}
175};
176
177static int __init ipc_sysctl_init(void)
178{
179 register_sysctl_table(ipc_root_table);
180 return 0;
181}
182
183__initcall(ipc_sysctl_init);
184
