diff options
Diffstat (limited to 'kernel/utsname_sysctl.c')
-rw-r--r-- | kernel/utsname_sysctl.c | 146 |
1 files changed, 146 insertions, 0 deletions
diff --git a/kernel/utsname_sysctl.c b/kernel/utsname_sysctl.c new file mode 100644 index 000000000000..f22b9dbd2a9c --- /dev/null +++ b/kernel/utsname_sysctl.c | |||
@@ -0,0 +1,146 @@ | |||
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/version.h> | ||
16 | #include <linux/sysctl.h> | ||
17 | |||
18 | static void *get_uts(ctl_table *table, int write) | ||
19 | { | ||
20 | char *which = table->data; | ||
21 | #ifdef CONFIG_UTS_NS | ||
22 | struct uts_namespace *uts_ns = current->nsproxy->uts_ns; | ||
23 | which = (which - (char *)&init_uts_ns) + (char *)uts_ns; | ||
24 | #endif | ||
25 | if (!write) | ||
26 | down_read(&uts_sem); | ||
27 | else | ||
28 | down_write(&uts_sem); | ||
29 | return which; | ||
30 | } | ||
31 | |||
32 | static 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_FS | ||
41 | /* | ||
42 | * Special case of dostring for the UTS structure. This has locks | ||
43 | * to observe. Should this be in kernel/sys.c ???? | ||
44 | */ | ||
45 | static int proc_do_uts_string(ctl_table *table, int write, struct file *filp, | ||
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,filp,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: */ | ||
63 | static int sysctl_uts_string(ctl_table *table, int __user *name, int nlen, | ||
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, name, nlen, | ||
73 | oldval, oldlenp, newval, newlen); | ||
74 | put_uts(table, write, uts_table.data); | ||
75 | return r; | ||
76 | } | ||
77 | #else | ||
78 | #define sysctl_uts_string NULL | ||
79 | #endif | ||
80 | |||
81 | static struct ctl_table uts_kern_table[] = { | ||
82 | { | ||
83 | .ctl_name = KERN_OSTYPE, | ||
84 | .procname = "ostype", | ||
85 | .data = init_uts_ns.name.sysname, | ||
86 | .maxlen = sizeof(init_uts_ns.name.sysname), | ||
87 | .mode = 0444, | ||
88 | .proc_handler = proc_do_uts_string, | ||
89 | .strategy = sysctl_uts_string, | ||
90 | }, | ||
91 | { | ||
92 | .ctl_name = KERN_OSRELEASE, | ||
93 | .procname = "osrelease", | ||
94 | .data = init_uts_ns.name.release, | ||
95 | .maxlen = sizeof(init_uts_ns.name.release), | ||
96 | .mode = 0444, | ||
97 | .proc_handler = proc_do_uts_string, | ||
98 | .strategy = sysctl_uts_string, | ||
99 | }, | ||
100 | { | ||
101 | .ctl_name = KERN_VERSION, | ||
102 | .procname = "version", | ||
103 | .data = init_uts_ns.name.version, | ||
104 | .maxlen = sizeof(init_uts_ns.name.version), | ||
105 | .mode = 0444, | ||
106 | .proc_handler = proc_do_uts_string, | ||
107 | .strategy = sysctl_uts_string, | ||
108 | }, | ||
109 | { | ||
110 | .ctl_name = KERN_NODENAME, | ||
111 | .procname = "hostname", | ||
112 | .data = init_uts_ns.name.nodename, | ||
113 | .maxlen = sizeof(init_uts_ns.name.nodename), | ||
114 | .mode = 0644, | ||
115 | .proc_handler = proc_do_uts_string, | ||
116 | .strategy = sysctl_uts_string, | ||
117 | }, | ||
118 | { | ||
119 | .ctl_name = KERN_DOMAINNAME, | ||
120 | .procname = "domainname", | ||
121 | .data = init_uts_ns.name.domainname, | ||
122 | .maxlen = sizeof(init_uts_ns.name.domainname), | ||
123 | .mode = 0644, | ||
124 | .proc_handler = proc_do_uts_string, | ||
125 | .strategy = sysctl_uts_string, | ||
126 | }, | ||
127 | {} | ||
128 | }; | ||
129 | |||
130 | static struct ctl_table uts_root_table[] = { | ||
131 | { | ||
132 | .ctl_name = CTL_KERN, | ||
133 | .procname = "kernel", | ||
134 | .mode = 0555, | ||
135 | .child = uts_kern_table, | ||
136 | }, | ||
137 | {} | ||
138 | }; | ||
139 | |||
140 | static int __init utsname_sysctl_init(void) | ||
141 | { | ||
142 | register_sysctl_table(uts_root_table); | ||
143 | return 0; | ||
144 | } | ||
145 | |||
146 | __initcall(utsname_sysctl_init); | ||