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12#include <linux/nsproxy.h>
13#include <linux/ipc_namespace.h>
14#include <linux/sysctl.h>
15
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17
18
19
20#define MIN_MSGMAX 1
21#define MAX_MSGMAX HARD_MSGMAX
22#define MIN_MSGSIZEMAX 128
23#define MAX_MSGSIZEMAX (8192*128)
24
25#ifdef CONFIG_PROC_SYSCTL
26static void *get_mq(ctl_table *table)
27{
28 char *which = table->data;
29 struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns;
30 which = (which - (char *)&init_ipc_ns) + (char *)ipc_ns;
31 return which;
32}
33
34static int proc_mq_dointvec(ctl_table *table, int write,
35 void __user *buffer, size_t *lenp, loff_t *ppos)
36{
37 struct ctl_table mq_table;
38 memcpy(&mq_table, table, sizeof(mq_table));
39 mq_table.data = get_mq(table);
40
41 return proc_dointvec(&mq_table, write, buffer, lenp, ppos);
42}
43
44static int proc_mq_dointvec_minmax(ctl_table *table, int write,
45 void __user *buffer, size_t *lenp, loff_t *ppos)
46{
47 struct ctl_table mq_table;
48 memcpy(&mq_table, table, sizeof(mq_table));
49 mq_table.data = get_mq(table);
50
51 return proc_dointvec_minmax(&mq_table, write, buffer,
52 lenp, ppos);
53}
54#else
55#define proc_mq_dointvec NULL
56#define proc_mq_dointvec_minmax NULL
57#endif
58
59static int msg_max_limit_min = MIN_MSGMAX;
60static int msg_max_limit_max = MAX_MSGMAX;
61
62static int msg_maxsize_limit_min = MIN_MSGSIZEMAX;
63static int msg_maxsize_limit_max = MAX_MSGSIZEMAX;
64
65static ctl_table mq_sysctls[] = {
66 {
67 .procname = "queues_max",
68 .data = &init_ipc_ns.mq_queues_max,
69 .maxlen = sizeof(int),
70 .mode = 0644,
71 .proc_handler = proc_mq_dointvec,
72 },
73 {
74 .procname = "msg_max",
75 .data = &init_ipc_ns.mq_msg_max,
76 .maxlen = sizeof(int),
77 .mode = 0644,
78 .proc_handler = proc_mq_dointvec_minmax,
79 .extra1 = &msg_max_limit_min,
80 .extra2 = &msg_max_limit_max,
81 },
82 {
83 .procname = "msgsize_max",
84 .data = &init_ipc_ns.mq_msgsize_max,
85 .maxlen = sizeof(int),
86 .mode = 0644,
87 .proc_handler = proc_mq_dointvec_minmax,
88 .extra1 = &msg_maxsize_limit_min,
89 .extra2 = &msg_maxsize_limit_max,
90 },
91 {}
92};
93
94static ctl_table mq_sysctl_dir[] = {
95 {
96 .procname = "mqueue",
97 .mode = 0555,
98 .child = mq_sysctls,
99 },
100 {}
101};
102
103static ctl_table mq_sysctl_root[] = {
104 {
105 .procname = "fs",
106 .mode = 0555,
107 .child = mq_sysctl_dir,
108 },
109 {}
110};
111
112struct ctl_table_header *mq_register_sysctl_table(void)
113{
114 return register_sysctl_table(mq_sysctl_root);
115}
116