| 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 | struct ctl_table_header *empty_add; |
| 39 | struct ctl_table_header *empty; |
| 40 | } sysctl_test_headers; |
| 41 | |
| 42 | struct test_sysctl_data { |
| 43 | int int_0001; |
| 44 | int int_0002; |
| 45 | int int_0003[4]; |
| 46 | |
| 47 | int boot_int; |
| 48 | |
| 49 | unsigned int uint_0001; |
| 50 | |
| 51 | char string_0001[65]; |
| 52 | |
| 53 | #define SYSCTL_TEST_BITMAP_SIZE 65536 |
| 54 | unsigned long *bitmap_0001; |
| 55 | }; |
| 56 | |
| 57 | static struct test_sysctl_data test_data = { |
| 58 | .int_0001 = 60, |
| 59 | .int_0002 = 1, |
| 60 | |
| 61 | .int_0003[0] = 0, |
| 62 | .int_0003[1] = 1, |
| 63 | .int_0003[2] = 2, |
| 64 | .int_0003[3] = 3, |
| 65 | |
| 66 | .boot_int = 0, |
| 67 | |
| 68 | .uint_0001 = 314, |
| 69 | |
| 70 | .string_0001 = "(none)", |
| 71 | }; |
| 72 | |
| 73 | /* These are all under /proc/sys/debug/test_sysctl/ */ |
| 74 | static struct ctl_table test_table[] = { |
| 75 | { |
| 76 | .procname = "int_0001", |
| 77 | .data = &test_data.int_0001, |
| 78 | .maxlen = sizeof(int), |
| 79 | .mode = 0644, |
| 80 | .proc_handler = proc_dointvec_minmax, |
| 81 | .extra1 = &i_zero, |
| 82 | .extra2 = &i_one_hundred, |
| 83 | }, |
| 84 | { |
| 85 | .procname = "int_0002", |
| 86 | .data = &test_data.int_0002, |
| 87 | .maxlen = sizeof(int), |
| 88 | .mode = 0644, |
| 89 | .proc_handler = proc_dointvec, |
| 90 | }, |
| 91 | { |
| 92 | .procname = "int_0003", |
| 93 | .data = &test_data.int_0003, |
| 94 | .maxlen = sizeof(test_data.int_0003), |
| 95 | .mode = 0644, |
| 96 | .proc_handler = proc_dointvec, |
| 97 | }, |
| 98 | { |
| 99 | .procname = "match_int", |
| 100 | .data = &match_int_ok, |
| 101 | .maxlen = sizeof(match_int_ok), |
| 102 | .mode = 0444, |
| 103 | .proc_handler = proc_dointvec, |
| 104 | }, |
| 105 | { |
| 106 | .procname = "boot_int", |
| 107 | .data = &test_data.boot_int, |
| 108 | .maxlen = sizeof(test_data.boot_int), |
| 109 | .mode = 0644, |
| 110 | .proc_handler = proc_dointvec, |
| 111 | .extra1 = SYSCTL_ZERO, |
| 112 | .extra2 = SYSCTL_ONE, |
| 113 | }, |
| 114 | { |
| 115 | .procname = "uint_0001", |
| 116 | .data = &test_data.uint_0001, |
| 117 | .maxlen = sizeof(unsigned int), |
| 118 | .mode = 0644, |
| 119 | .proc_handler = proc_douintvec, |
| 120 | }, |
| 121 | { |
| 122 | .procname = "string_0001", |
| 123 | .data = &test_data.string_0001, |
| 124 | .maxlen = sizeof(test_data.string_0001), |
| 125 | .mode = 0644, |
| 126 | .proc_handler = proc_dostring, |
| 127 | }, |
| 128 | { |
| 129 | .procname = "bitmap_0001", |
| 130 | .data = &test_data.bitmap_0001, |
| 131 | .maxlen = SYSCTL_TEST_BITMAP_SIZE, |
| 132 | .mode = 0644, |
| 133 | .proc_handler = proc_do_large_bitmap, |
| 134 | }, |
| 135 | }; |
| 136 | |
| 137 | static void test_sysctl_calc_match_int_ok(void) |
| 138 | { |
| 139 | int i; |
| 140 | |
| 141 | struct { |
| 142 | int defined; |
| 143 | int wanted; |
| 144 | } match_int[] = { |
| 145 | {.defined = *(int *)SYSCTL_ZERO, .wanted = 0}, |
| 146 | {.defined = *(int *)SYSCTL_ONE, .wanted = 1}, |
| 147 | {.defined = *(int *)SYSCTL_TWO, .wanted = 2}, |
| 148 | {.defined = *(int *)SYSCTL_THREE, .wanted = 3}, |
| 149 | {.defined = *(int *)SYSCTL_FOUR, .wanted = 4}, |
| 150 | {.defined = *(int *)SYSCTL_ONE_HUNDRED, .wanted = 100}, |
| 151 | {.defined = *(int *)SYSCTL_TWO_HUNDRED, .wanted = 200}, |
| 152 | {.defined = *(int *)SYSCTL_ONE_THOUSAND, .wanted = 1000}, |
| 153 | {.defined = *(int *)SYSCTL_THREE_THOUSAND, .wanted = 3000}, |
| 154 | {.defined = *(int *)SYSCTL_INT_MAX, .wanted = INT_MAX}, |
| 155 | {.defined = *(int *)SYSCTL_MAXOLDUID, .wanted = 65535}, |
| 156 | {.defined = *(int *)SYSCTL_NEG_ONE, .wanted = -1}, |
| 157 | }; |
| 158 | |
| 159 | for (i = 0; i < ARRAY_SIZE(match_int); i++) |
| 160 | if (match_int[i].defined != match_int[i].wanted) |
| 161 | match_int_ok = 0; |
| 162 | } |
| 163 | |
| 164 | static int test_sysctl_setup_node_tests(void) |
| 165 | { |
| 166 | test_sysctl_calc_match_int_ok(); |
| 167 | test_data.bitmap_0001 = kzalloc(SYSCTL_TEST_BITMAP_SIZE/8, GFP_KERNEL); |
| 168 | if (!test_data.bitmap_0001) |
| 169 | return -ENOMEM; |
| 170 | sysctl_test_headers.test_h_setup_node = register_sysctl("debug/test_sysctl", test_table); |
| 171 | if (!sysctl_test_headers.test_h_setup_node) { |
| 172 | kfree(test_data.bitmap_0001); |
| 173 | return -ENOMEM; |
| 174 | } |
| 175 | |
| 176 | return 0; |
| 177 | } |
| 178 | |
| 179 | /* Used to test that unregister actually removes the directory */ |
| 180 | static struct ctl_table test_table_unregister[] = { |
| 181 | { |
| 182 | .procname = "unregister_error", |
| 183 | .data = &test_data.int_0001, |
| 184 | .maxlen = sizeof(int), |
| 185 | .mode = 0644, |
| 186 | .proc_handler = proc_dointvec_minmax, |
| 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(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("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 struct ctl_table test_table_empty[] = { }; |
| 224 | |
| 225 | static int test_sysctl_run_register_empty(void) |
| 226 | { |
| 227 | /* Tets that an empty dir can be created */ |
| 228 | sysctl_test_headers.empty_add |
| 229 | = register_sysctl("debug/test_sysctl/empty_add", test_table_empty); |
| 230 | if (!sysctl_test_headers.empty_add) |
| 231 | return -ENOMEM; |
| 232 | |
| 233 | /* Test that register on top of an empty dir works */ |
| 234 | sysctl_test_headers.empty |
| 235 | = register_sysctl("debug/test_sysctl/empty_add/empty", test_table_empty); |
| 236 | if (!sysctl_test_headers.empty) |
| 237 | return -ENOMEM; |
| 238 | |
| 239 | return 0; |
| 240 | } |
| 241 | |
| 242 | static int __init test_sysctl_init(void) |
| 243 | { |
| 244 | int err; |
| 245 | |
| 246 | err = test_sysctl_setup_node_tests(); |
| 247 | if (err) |
| 248 | goto out; |
| 249 | |
| 250 | err = test_sysctl_run_unregister_nested(); |
| 251 | if (err) |
| 252 | goto out; |
| 253 | |
| 254 | err = test_sysctl_run_register_mount_point(); |
| 255 | if (err) |
| 256 | goto out; |
| 257 | |
| 258 | err = test_sysctl_run_register_empty(); |
| 259 | |
| 260 | out: |
| 261 | return err; |
| 262 | } |
| 263 | module_init(test_sysctl_init); |
| 264 | |
| 265 | static void __exit test_sysctl_exit(void) |
| 266 | { |
| 267 | kfree(test_data.bitmap_0001); |
| 268 | if (sysctl_test_headers.test_h_setup_node) |
| 269 | unregister_sysctl_table(sysctl_test_headers.test_h_setup_node); |
| 270 | if (sysctl_test_headers.test_h_mnt) |
| 271 | unregister_sysctl_table(sysctl_test_headers.test_h_mnt); |
| 272 | if (sysctl_test_headers.test_h_mnterror) |
| 273 | unregister_sysctl_table(sysctl_test_headers.test_h_mnterror); |
| 274 | if (sysctl_test_headers.empty) |
| 275 | unregister_sysctl_table(sysctl_test_headers.empty); |
| 276 | if (sysctl_test_headers.empty_add) |
| 277 | unregister_sysctl_table(sysctl_test_headers.empty_add); |
| 278 | } |
| 279 | |
| 280 | module_exit(test_sysctl_exit); |
| 281 | |
| 282 | MODULE_AUTHOR("Luis R. Rodriguez <mcgrof@kernel.org>"); |
| 283 | MODULE_LICENSE("GPL"); |