Root/kernel/utsname_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/uts.h>
14#include <linux/utsname.h>
15#include <linux/sysctl.h>
16
17static void *get_uts(ctl_table *table, int write)
18{
19    char *which = table->data;
20    struct uts_namespace *uts_ns;
21
22    uts_ns = current->nsproxy->uts_ns;
23    which = (which - (char *)&init_uts_ns) + (char *)uts_ns;
24
25    if (!write)
26        down_read(&uts_sem);
27    else
28        down_write(&uts_sem);
29    return which;
30}
31
32static void put_uts(ctl_table *table, int write, void *which)
33{
34    if (!write)
35        up_read(&uts_sem);
36    else
37        up_write(&uts_sem);
38}
39
40#ifdef CONFIG_PROC_SYSCTL
41/*
42 * Special case of dostring for the UTS structure. This has locks
43 * to observe. Should this be in kernel/sys.c ????
44 */
45static int proc_do_uts_string(ctl_table *table, int write,
46          void __user *buffer, size_t *lenp, loff_t *ppos)
47{
48    struct ctl_table uts_table;
49    int r;
50    memcpy(&uts_table, table, sizeof(uts_table));
51    uts_table.data = get_uts(table, write);
52    r = proc_dostring(&uts_table,write,buffer,lenp, ppos);
53    put_uts(table, write, uts_table.data);
54    return r;
55}
56#else
57#define proc_do_uts_string NULL
58#endif
59
60
61#ifdef CONFIG_SYSCTL_SYSCALL
62/* The generic string strategy routine: */
63static int sysctl_uts_string(ctl_table *table,
64          void __user *oldval, size_t __user *oldlenp,
65          void __user *newval, size_t newlen)
66{
67    struct ctl_table uts_table;
68    int r, write;
69    write = newval && newlen;
70    memcpy(&uts_table, table, sizeof(uts_table));
71    uts_table.data = get_uts(table, write);
72    r = sysctl_string(&uts_table, oldval, oldlenp, newval, newlen);
73    put_uts(table, write, uts_table.data);
74    return r;
75}
76#else
77#define sysctl_uts_string NULL
78#endif
79
80static struct ctl_table uts_kern_table[] = {
81    {
82        .ctl_name = KERN_OSTYPE,
83        .procname = "ostype",
84        .data = init_uts_ns.name.sysname,
85        .maxlen = sizeof(init_uts_ns.name.sysname),
86        .mode = 0444,
87        .proc_handler = proc_do_uts_string,
88        .strategy = sysctl_uts_string,
89    },
90    {
91        .ctl_name = KERN_OSRELEASE,
92        .procname = "osrelease",
93        .data = init_uts_ns.name.release,
94        .maxlen = sizeof(init_uts_ns.name.release),
95        .mode = 0444,
96        .proc_handler = proc_do_uts_string,
97        .strategy = sysctl_uts_string,
98    },
99    {
100        .ctl_name = KERN_VERSION,
101        .procname = "version",
102        .data = init_uts_ns.name.version,
103        .maxlen = sizeof(init_uts_ns.name.version),
104        .mode = 0444,
105        .proc_handler = proc_do_uts_string,
106        .strategy = sysctl_uts_string,
107    },
108    {
109        .ctl_name = KERN_NODENAME,
110        .procname = "hostname",
111        .data = init_uts_ns.name.nodename,
112        .maxlen = sizeof(init_uts_ns.name.nodename),
113        .mode = 0644,
114        .proc_handler = proc_do_uts_string,
115        .strategy = sysctl_uts_string,
116    },
117    {
118        .ctl_name = KERN_DOMAINNAME,
119        .procname = "domainname",
120        .data = init_uts_ns.name.domainname,
121        .maxlen = sizeof(init_uts_ns.name.domainname),
122        .mode = 0644,
123        .proc_handler = proc_do_uts_string,
124        .strategy = sysctl_uts_string,
125    },
126    {}
127};
128
129static struct ctl_table uts_root_table[] = {
130    {
131        .ctl_name = CTL_KERN,
132        .procname = "kernel",
133        .mode = 0555,
134        .child = uts_kern_table,
135    },
136    {}
137};
138
139static int __init utsname_sysctl_init(void)
140{
141    register_sysctl_table(uts_root_table);
142    return 0;
143}
144
145__initcall(utsname_sysctl_init);
146

Archive Download this file

Branches:
ben-wpan
ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
jz-2.6.34-rc6
jz-2.6.34-rc7
jz-2.6.35
jz-2.6.36
jz-2.6.37
jz-2.6.38
jz-2.6.39
jz-3.0
jz-3.1
jz-3.11
jz-3.12
jz-3.13
jz-3.15
jz-3.16
jz-3.18-dt
jz-3.2
jz-3.3
jz-3.4
jz-3.5
jz-3.6
jz-3.6-rc2-pwm
jz-3.9
jz-3.9-clk
jz-3.9-rc8
jz47xx
jz47xx-2.6.38
master

Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9



interactive