1 | // SPDX-License-Identifier: GPL-2.0-or-later OR copyleft-next-0.3.1 |
2 | /* |
3 | * proc sysctl test driver |
4 | * |
5 | * Copyright (C) 2017 Luis R. Rodriguez <mcgrof@kernel.org> |
6 | */ |
7 | |
8 | /* |
9 | * This module provides an interface to the proc sysctl interfaces. This |
10 | * driver requires CONFIG_PROC_SYSCTL. It will not normally be loaded by the |
11 | * system unless explicitly requested by name. You can also build this driver |
12 | * into your kernel. |
13 | */ |
14 | |
15 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
16 | |
17 | #include <linux/init.h> |
18 | #include <linux/list.h> |
19 | #include <linux/module.h> |
20 | #include <linux/printk.h> |
21 | #include <linux/fs.h> |
22 | #include <linux/miscdevice.h> |
23 | #include <linux/slab.h> |
24 | #include <linux/uaccess.h> |
25 | #include <linux/async.h> |
26 | #include <linux/delay.h> |
27 | #include <linux/vmalloc.h> |
28 | |
29 | static int i_zero; |
30 | static int i_one_hundred = 100; |
31 | static int match_int_ok = 1; |
32 | |
33 | |
34 | static struct { |
35 | struct ctl_table_header *test_h_setup_node; |
36 | struct ctl_table_header *test_h_mnt; |
37 | struct ctl_table_header *test_h_mnterror; |
38 | } ; |
39 | |
40 | struct test_sysctl_data { |
41 | int int_0001; |
42 | int int_0002; |
43 | int int_0003[4]; |
44 | |
45 | int boot_int; |
46 | |
47 | unsigned int uint_0001; |
48 | |
49 | char string_0001[65]; |
50 | |
51 | #define SYSCTL_TEST_BITMAP_SIZE 65536 |
52 | unsigned long *bitmap_0001; |
53 | }; |
54 | |
55 | static struct test_sysctl_data test_data = { |
56 | .int_0001 = 60, |
57 | .int_0002 = 1, |
58 | |
59 | .int_0003[0] = 0, |
60 | .int_0003[1] = 1, |
61 | .int_0003[2] = 2, |
62 | .int_0003[3] = 3, |
63 | |
64 | .boot_int = 0, |
65 | |
66 | .uint_0001 = 314, |
67 | |
68 | .string_0001 = "(none)" , |
69 | }; |
70 | |
71 | /* These are all under /proc/sys/debug/test_sysctl/ */ |
72 | static struct ctl_table test_table[] = { |
73 | { |
74 | .procname = "int_0001" , |
75 | .data = &test_data.int_0001, |
76 | .maxlen = sizeof(int), |
77 | .mode = 0644, |
78 | .proc_handler = proc_dointvec_minmax, |
79 | .extra1 = &i_zero, |
80 | .extra2 = &i_one_hundred, |
81 | }, |
82 | { |
83 | .procname = "int_0002" , |
84 | .data = &test_data.int_0002, |
85 | .maxlen = sizeof(int), |
86 | .mode = 0644, |
87 | .proc_handler = proc_dointvec, |
88 | }, |
89 | { |
90 | .procname = "int_0003" , |
91 | .data = &test_data.int_0003, |
92 | .maxlen = sizeof(test_data.int_0003), |
93 | .mode = 0644, |
94 | .proc_handler = proc_dointvec, |
95 | }, |
96 | { |
97 | .procname = "match_int" , |
98 | .data = &match_int_ok, |
99 | .maxlen = sizeof(match_int_ok), |
100 | .mode = 0444, |
101 | .proc_handler = proc_dointvec, |
102 | }, |
103 | { |
104 | .procname = "boot_int" , |
105 | .data = &test_data.boot_int, |
106 | .maxlen = sizeof(test_data.boot_int), |
107 | .mode = 0644, |
108 | .proc_handler = proc_dointvec, |
109 | .extra1 = SYSCTL_ZERO, |
110 | .extra2 = SYSCTL_ONE, |
111 | }, |
112 | { |
113 | .procname = "uint_0001" , |
114 | .data = &test_data.uint_0001, |
115 | .maxlen = sizeof(unsigned int), |
116 | .mode = 0644, |
117 | .proc_handler = proc_douintvec, |
118 | }, |
119 | { |
120 | .procname = "string_0001" , |
121 | .data = &test_data.string_0001, |
122 | .maxlen = sizeof(test_data.string_0001), |
123 | .mode = 0644, |
124 | .proc_handler = proc_dostring, |
125 | }, |
126 | { |
127 | .procname = "bitmap_0001" , |
128 | .data = &test_data.bitmap_0001, |
129 | .maxlen = SYSCTL_TEST_BITMAP_SIZE, |
130 | .mode = 0644, |
131 | .proc_handler = proc_do_large_bitmap, |
132 | }, |
133 | { } |
134 | }; |
135 | |
136 | static void test_sysctl_calc_match_int_ok(void) |
137 | { |
138 | int i; |
139 | |
140 | struct { |
141 | int defined; |
142 | int wanted; |
143 | } match_int[] = { |
144 | {.defined = *(int *)SYSCTL_ZERO, .wanted = 0}, |
145 | {.defined = *(int *)SYSCTL_ONE, .wanted = 1}, |
146 | {.defined = *(int *)SYSCTL_TWO, .wanted = 2}, |
147 | {.defined = *(int *)SYSCTL_THREE, .wanted = 3}, |
148 | {.defined = *(int *)SYSCTL_FOUR, .wanted = 4}, |
149 | {.defined = *(int *)SYSCTL_ONE_HUNDRED, .wanted = 100}, |
150 | {.defined = *(int *)SYSCTL_TWO_HUNDRED, .wanted = 200}, |
151 | {.defined = *(int *)SYSCTL_ONE_THOUSAND, .wanted = 1000}, |
152 | {.defined = *(int *)SYSCTL_THREE_THOUSAND, .wanted = 3000}, |
153 | {.defined = *(int *)SYSCTL_INT_MAX, .wanted = INT_MAX}, |
154 | {.defined = *(int *)SYSCTL_MAXOLDUID, .wanted = 65535}, |
155 | {.defined = *(int *)SYSCTL_NEG_ONE, .wanted = -1}, |
156 | }; |
157 | |
158 | for (i = 0; i < ARRAY_SIZE(match_int); i++) |
159 | if (match_int[i].defined != match_int[i].wanted) |
160 | match_int_ok = 0; |
161 | } |
162 | |
163 | static int test_sysctl_setup_node_tests(void) |
164 | { |
165 | test_sysctl_calc_match_int_ok(); |
166 | test_data.bitmap_0001 = kzalloc(SYSCTL_TEST_BITMAP_SIZE/8, GFP_KERNEL); |
167 | if (!test_data.bitmap_0001) |
168 | return -ENOMEM; |
169 | sysctl_test_headers.test_h_setup_node = register_sysctl("debug/test_sysctl" , test_table); |
170 | if (!sysctl_test_headers.test_h_setup_node) { |
171 | kfree(objp: test_data.bitmap_0001); |
172 | return -ENOMEM; |
173 | } |
174 | |
175 | return 0; |
176 | } |
177 | |
178 | /* Used to test that unregister actually removes the directory */ |
179 | static struct ctl_table test_table_unregister[] = { |
180 | { |
181 | .procname = "unregister_error" , |
182 | .data = &test_data.int_0001, |
183 | .maxlen = sizeof(int), |
184 | .mode = 0644, |
185 | .proc_handler = proc_dointvec_minmax, |
186 | }, |
187 | {} |
188 | }; |
189 | |
190 | static int test_sysctl_run_unregister_nested(void) |
191 | { |
192 | struct ctl_table_header *unregister; |
193 | |
194 | unregister = register_sysctl("debug/test_sysctl/unregister_error" , |
195 | test_table_unregister); |
196 | if (!unregister) |
197 | return -ENOMEM; |
198 | |
199 | unregister_sysctl_table(table: unregister); |
200 | return 0; |
201 | } |
202 | |
203 | static int test_sysctl_run_register_mount_point(void) |
204 | { |
205 | sysctl_test_headers.test_h_mnt |
206 | = register_sysctl_mount_point(path: "debug/test_sysctl/mnt" ); |
207 | if (!sysctl_test_headers.test_h_mnt) |
208 | return -ENOMEM; |
209 | |
210 | sysctl_test_headers.test_h_mnterror |
211 | = register_sysctl("debug/test_sysctl/mnt/mnt_error" , |
212 | test_table_unregister); |
213 | /* |
214 | * Don't check the result.: |
215 | * If it fails (expected behavior), return 0. |
216 | * If successful (missbehavior of register mount point), we want to see |
217 | * mnt_error when we run the sysctl test script |
218 | */ |
219 | |
220 | return 0; |
221 | } |
222 | |
223 | static int __init test_sysctl_init(void) |
224 | { |
225 | int err; |
226 | |
227 | err = test_sysctl_setup_node_tests(); |
228 | if (err) |
229 | goto out; |
230 | |
231 | err = test_sysctl_run_unregister_nested(); |
232 | if (err) |
233 | goto out; |
234 | |
235 | err = test_sysctl_run_register_mount_point(); |
236 | |
237 | out: |
238 | return err; |
239 | } |
240 | module_init(test_sysctl_init); |
241 | |
242 | static void __exit test_sysctl_exit(void) |
243 | { |
244 | kfree(objp: test_data.bitmap_0001); |
245 | if (sysctl_test_headers.test_h_setup_node) |
246 | unregister_sysctl_table(table: sysctl_test_headers.test_h_setup_node); |
247 | if (sysctl_test_headers.test_h_mnt) |
248 | unregister_sysctl_table(table: sysctl_test_headers.test_h_mnt); |
249 | if (sysctl_test_headers.test_h_mnterror) |
250 | unregister_sysctl_table(table: sysctl_test_headers.test_h_mnterror); |
251 | } |
252 | |
253 | module_exit(test_sysctl_exit); |
254 | |
255 | MODULE_AUTHOR("Luis R. Rodriguez <mcgrof@kernel.org>" ); |
256 | MODULE_LICENSE("GPL" ); |
257 | |