Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Kprobe module for testing crash dumps |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify |
| 5 | * it under the terms of the GNU General Public License as published by |
| 6 | * the Free Software Foundation; either version 2 of the License, or |
| 7 | * (at your option) any later version. |
| 8 | * |
| 9 | * This program is distributed in the hope that it will be useful, |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 | * GNU General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU General Public License |
| 15 | * along with this program; if not, write to the Free Software |
| 16 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 17 | * |
| 18 | * Copyright (C) IBM Corporation, 2006 |
| 19 | * |
| 20 | * Author: Ankita Garg <ankita@in.ibm.com> |
| 21 | * |
| 22 | * This module induces system failures at predefined crashpoints to |
| 23 | * evaluate the reliability of crash dumps obtained using different dumping |
| 24 | * solutions. |
| 25 | * |
| 26 | * It is adapted from the Linux Kernel Dump Test Tool by |
| 27 | * Fernando Luis Vazquez Cao <http://lkdtt.sourceforge.net> |
| 28 | * |
Simon Kagstrom | 0347af4 | 2010-03-05 13:42:49 -0800 | [diff] [blame] | 29 | * Debugfs support added by Simon Kagstrom <simon.kagstrom@netinsight.net> |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 30 | * |
Simon Kagstrom | 0347af4 | 2010-03-05 13:42:49 -0800 | [diff] [blame] | 31 | * See Documentation/fault-injection/provoke-crashes.txt for instructions |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 32 | */ |
| 33 | |
| 34 | #include <linux/kernel.h> |
Randy Dunlap | 5d861d9 | 2006-11-02 22:07:06 -0800 | [diff] [blame] | 35 | #include <linux/fs.h> |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 36 | #include <linux/module.h> |
Randy Dunlap | 5d861d9 | 2006-11-02 22:07:06 -0800 | [diff] [blame] | 37 | #include <linux/buffer_head.h> |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 38 | #include <linux/kprobes.h> |
Randy Dunlap | 5d861d9 | 2006-11-02 22:07:06 -0800 | [diff] [blame] | 39 | #include <linux/list.h> |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 40 | #include <linux/init.h> |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 41 | #include <linux/interrupt.h> |
Randy Dunlap | 5d861d9 | 2006-11-02 22:07:06 -0800 | [diff] [blame] | 42 | #include <linux/hrtimer.h> |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 43 | #include <scsi/scsi_cmnd.h> |
Simon Kagstrom | 0347af4 | 2010-03-05 13:42:49 -0800 | [diff] [blame] | 44 | #include <linux/debugfs.h> |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 45 | |
| 46 | #ifdef CONFIG_IDE |
| 47 | #include <linux/ide.h> |
| 48 | #endif |
| 49 | |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 50 | #define DEFAULT_COUNT 10 |
| 51 | #define REC_NUM_DEFAULT 10 |
| 52 | |
| 53 | enum cname { |
| 54 | INVALID, |
| 55 | INT_HARDWARE_ENTRY, |
| 56 | INT_HW_IRQ_EN, |
| 57 | INT_TASKLET_ENTRY, |
| 58 | FS_DEVRW, |
| 59 | MEM_SWAPOUT, |
| 60 | TIMERADD, |
| 61 | SCSI_DISPATCH_CMD, |
Simon Kagstrom | 0347af4 | 2010-03-05 13:42:49 -0800 | [diff] [blame] | 62 | IDE_CORE_CP, |
| 63 | DIRECT, |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 64 | }; |
| 65 | |
| 66 | enum ctype { |
| 67 | NONE, |
| 68 | PANIC, |
| 69 | BUG, |
| 70 | EXCEPTION, |
| 71 | LOOP, |
Simon Kagstrom | 0347af4 | 2010-03-05 13:42:49 -0800 | [diff] [blame] | 72 | OVERFLOW, |
| 73 | CORRUPT_STACK, |
| 74 | UNALIGNED_LOAD_STORE_WRITE, |
| 75 | OVERWRITE_ALLOCATION, |
| 76 | WRITE_AFTER_FREE, |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 77 | }; |
| 78 | |
| 79 | static char* cp_name[] = { |
| 80 | "INT_HARDWARE_ENTRY", |
| 81 | "INT_HW_IRQ_EN", |
| 82 | "INT_TASKLET_ENTRY", |
| 83 | "FS_DEVRW", |
| 84 | "MEM_SWAPOUT", |
| 85 | "TIMERADD", |
| 86 | "SCSI_DISPATCH_CMD", |
Simon Kagstrom | 0347af4 | 2010-03-05 13:42:49 -0800 | [diff] [blame] | 87 | "IDE_CORE_CP", |
| 88 | "DIRECT", |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 89 | }; |
| 90 | |
| 91 | static char* cp_type[] = { |
| 92 | "PANIC", |
| 93 | "BUG", |
| 94 | "EXCEPTION", |
| 95 | "LOOP", |
Simon Kagstrom | 0347af4 | 2010-03-05 13:42:49 -0800 | [diff] [blame] | 96 | "OVERFLOW", |
| 97 | "CORRUPT_STACK", |
| 98 | "UNALIGNED_LOAD_STORE_WRITE", |
| 99 | "OVERWRITE_ALLOCATION", |
| 100 | "WRITE_AFTER_FREE", |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 101 | }; |
| 102 | |
| 103 | static struct jprobe lkdtm; |
| 104 | |
| 105 | static int lkdtm_parse_commandline(void); |
| 106 | static void lkdtm_handler(void); |
| 107 | |
Al Viro | ec1c620 | 2007-02-09 16:05:17 +0000 | [diff] [blame] | 108 | static char* cpoint_name; |
| 109 | static char* cpoint_type; |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 110 | static int cpoint_count = DEFAULT_COUNT; |
| 111 | static int recur_count = REC_NUM_DEFAULT; |
| 112 | |
| 113 | static enum cname cpoint = INVALID; |
| 114 | static enum ctype cptype = NONE; |
| 115 | static int count = DEFAULT_COUNT; |
| 116 | |
| 117 | module_param(recur_count, int, 0644); |
Randy Dunlap | 5d861d9 | 2006-11-02 22:07:06 -0800 | [diff] [blame] | 118 | MODULE_PARM_DESC(recur_count, " Recursion level for the stack overflow test, "\ |
| 119 | "default is 10"); |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 120 | module_param(cpoint_name, charp, 0644); |
Randy Dunlap | 5d861d9 | 2006-11-02 22:07:06 -0800 | [diff] [blame] | 121 | MODULE_PARM_DESC(cpoint_name, " Crash Point, where kernel is to be crashed"); |
| 122 | module_param(cpoint_type, charp, 0644); |
| 123 | MODULE_PARM_DESC(cpoint_type, " Crash Point Type, action to be taken on "\ |
| 124 | "hitting the crash point"); |
| 125 | module_param(cpoint_count, int, 0644); |
| 126 | MODULE_PARM_DESC(cpoint_count, " Crash Point Count, number of times the "\ |
| 127 | "crash point is to be hit to trigger action"); |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 128 | |
Adrian Bunk | 2118116 | 2008-02-06 01:36:50 -0800 | [diff] [blame] | 129 | static unsigned int jp_do_irq(unsigned int irq) |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 130 | { |
| 131 | lkdtm_handler(); |
| 132 | jprobe_return(); |
| 133 | return 0; |
| 134 | } |
| 135 | |
Adrian Bunk | 2118116 | 2008-02-06 01:36:50 -0800 | [diff] [blame] | 136 | static irqreturn_t jp_handle_irq_event(unsigned int irq, |
| 137 | struct irqaction *action) |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 138 | { |
| 139 | lkdtm_handler(); |
| 140 | jprobe_return(); |
| 141 | return 0; |
| 142 | } |
| 143 | |
Adrian Bunk | 2118116 | 2008-02-06 01:36:50 -0800 | [diff] [blame] | 144 | static void jp_tasklet_action(struct softirq_action *a) |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 145 | { |
| 146 | lkdtm_handler(); |
| 147 | jprobe_return(); |
| 148 | } |
| 149 | |
Adrian Bunk | 2118116 | 2008-02-06 01:36:50 -0800 | [diff] [blame] | 150 | static void jp_ll_rw_block(int rw, int nr, struct buffer_head *bhs[]) |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 151 | { |
| 152 | lkdtm_handler(); |
| 153 | jprobe_return(); |
| 154 | } |
| 155 | |
| 156 | struct scan_control; |
| 157 | |
Adrian Bunk | 2118116 | 2008-02-06 01:36:50 -0800 | [diff] [blame] | 158 | static unsigned long jp_shrink_inactive_list(unsigned long max_scan, |
| 159 | struct zone *zone, |
| 160 | struct scan_control *sc) |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 161 | { |
| 162 | lkdtm_handler(); |
| 163 | jprobe_return(); |
| 164 | return 0; |
| 165 | } |
| 166 | |
Adrian Bunk | 2118116 | 2008-02-06 01:36:50 -0800 | [diff] [blame] | 167 | static int jp_hrtimer_start(struct hrtimer *timer, ktime_t tim, |
| 168 | const enum hrtimer_mode mode) |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 169 | { |
| 170 | lkdtm_handler(); |
| 171 | jprobe_return(); |
| 172 | return 0; |
| 173 | } |
| 174 | |
Adrian Bunk | 2118116 | 2008-02-06 01:36:50 -0800 | [diff] [blame] | 175 | static int jp_scsi_dispatch_cmd(struct scsi_cmnd *cmd) |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 176 | { |
| 177 | lkdtm_handler(); |
| 178 | jprobe_return(); |
| 179 | return 0; |
| 180 | } |
| 181 | |
| 182 | #ifdef CONFIG_IDE |
| 183 | int jp_generic_ide_ioctl(ide_drive_t *drive, struct file *file, |
| 184 | struct block_device *bdev, unsigned int cmd, |
| 185 | unsigned long arg) |
| 186 | { |
| 187 | lkdtm_handler(); |
| 188 | jprobe_return(); |
| 189 | return 0; |
| 190 | } |
| 191 | #endif |
| 192 | |
Simon Kagstrom | 0347af4 | 2010-03-05 13:42:49 -0800 | [diff] [blame] | 193 | /* Return the crashpoint number or NONE if the name is invalid */ |
| 194 | static enum ctype parse_cp_type(const char *what, size_t count) |
| 195 | { |
| 196 | int i; |
| 197 | |
| 198 | for (i = 0; i < ARRAY_SIZE(cp_type); i++) { |
| 199 | if (!strcmp(what, cp_type[i])) |
| 200 | return i + 1; |
| 201 | } |
| 202 | |
| 203 | return NONE; |
| 204 | } |
| 205 | |
| 206 | static const char *cp_type_to_str(enum ctype type) |
| 207 | { |
| 208 | if (type == NONE || type < 0 || type > ARRAY_SIZE(cp_type)) |
| 209 | return "None"; |
| 210 | |
| 211 | return cp_type[type - 1]; |
| 212 | } |
| 213 | |
| 214 | static const char *cp_name_to_str(enum cname name) |
| 215 | { |
| 216 | if (name == INVALID || name < 0 || name > ARRAY_SIZE(cp_name)) |
| 217 | return "INVALID"; |
| 218 | |
| 219 | return cp_name[name - 1]; |
| 220 | } |
| 221 | |
| 222 | |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 223 | static int lkdtm_parse_commandline(void) |
| 224 | { |
| 225 | int i; |
| 226 | |
Simon Kagstrom | 0347af4 | 2010-03-05 13:42:49 -0800 | [diff] [blame] | 227 | if (cpoint_count < 1 || recur_count < 1) |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 228 | return -EINVAL; |
| 229 | |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 230 | count = cpoint_count; |
| 231 | |
Simon Kagstrom | 0347af4 | 2010-03-05 13:42:49 -0800 | [diff] [blame] | 232 | /* No special parameters */ |
| 233 | if (!cpoint_type && !cpoint_name) |
| 234 | return 0; |
| 235 | |
| 236 | /* Neither or both of these need to be set */ |
| 237 | if (!cpoint_type || !cpoint_name) |
| 238 | return -EINVAL; |
| 239 | |
| 240 | cptype = parse_cp_type(cpoint_type, strlen(cpoint_type)); |
| 241 | if (cptype == NONE) |
| 242 | return -EINVAL; |
| 243 | |
| 244 | for (i = 0; i < ARRAY_SIZE(cp_name); i++) { |
| 245 | if (!strcmp(cpoint_name, cp_name[i])) { |
| 246 | cpoint = i + 1; |
| 247 | return 0; |
| 248 | } |
| 249 | } |
| 250 | |
| 251 | /* Could not find a valid crash point */ |
| 252 | return -EINVAL; |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 253 | } |
| 254 | |
| 255 | static int recursive_loop(int a) |
| 256 | { |
| 257 | char buf[1024]; |
| 258 | |
| 259 | memset(buf,0xFF,1024); |
| 260 | recur_count--; |
| 261 | if (!recur_count) |
| 262 | return 0; |
| 263 | else |
| 264 | return recursive_loop(a); |
| 265 | } |
| 266 | |
Simon Kagstrom | 0347af4 | 2010-03-05 13:42:49 -0800 | [diff] [blame] | 267 | static void lkdtm_do_action(enum ctype which) |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 268 | { |
Simon Kagstrom | 0347af4 | 2010-03-05 13:42:49 -0800 | [diff] [blame] | 269 | switch (which) { |
| 270 | case PANIC: |
| 271 | panic("dumptest"); |
| 272 | break; |
| 273 | case BUG: |
| 274 | BUG(); |
| 275 | break; |
| 276 | case EXCEPTION: |
| 277 | *((int *) 0) = 0; |
| 278 | break; |
| 279 | case LOOP: |
| 280 | for (;;) |
| 281 | ; |
| 282 | break; |
| 283 | case OVERFLOW: |
| 284 | (void) recursive_loop(0); |
| 285 | break; |
| 286 | case CORRUPT_STACK: { |
| 287 | volatile u32 data[8]; |
| 288 | volatile u32 *p = data; |
| 289 | |
| 290 | p[12] = 0x12345678; |
| 291 | break; |
| 292 | } |
| 293 | case UNALIGNED_LOAD_STORE_WRITE: { |
| 294 | static u8 data[5] __attribute__((aligned(4))) = {1, 2, |
| 295 | 3, 4, 5}; |
| 296 | u32 *p; |
| 297 | u32 val = 0x12345678; |
| 298 | |
| 299 | p = (u32 *)(data + 1); |
| 300 | if (*p == 0) |
| 301 | val = 0x87654321; |
| 302 | *p = val; |
| 303 | break; |
| 304 | } |
| 305 | case OVERWRITE_ALLOCATION: { |
| 306 | size_t len = 1020; |
| 307 | u32 *data = kmalloc(len, GFP_KERNEL); |
| 308 | |
| 309 | data[1024 / sizeof(u32)] = 0x12345678; |
| 310 | kfree(data); |
| 311 | break; |
| 312 | } |
| 313 | case WRITE_AFTER_FREE: { |
| 314 | size_t len = 1024; |
| 315 | u32 *data = kmalloc(len, GFP_KERNEL); |
| 316 | |
| 317 | kfree(data); |
| 318 | schedule(); |
| 319 | memset(data, 0x78, len); |
| 320 | break; |
| 321 | } |
| 322 | case NONE: |
| 323 | default: |
| 324 | break; |
| 325 | } |
| 326 | |
| 327 | } |
| 328 | |
| 329 | static void lkdtm_handler(void) |
| 330 | { |
| 331 | count--; |
| 332 | printk(KERN_INFO "lkdtm: Crash point %s of type %s hit, trigger in %d rounds\n", |
| 333 | cp_name_to_str(cpoint), cp_type_to_str(cptype), count); |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 334 | |
| 335 | if (count == 0) { |
Simon Kagstrom | 0347af4 | 2010-03-05 13:42:49 -0800 | [diff] [blame] | 336 | lkdtm_do_action(cptype); |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 337 | count = cpoint_count; |
| 338 | } |
| 339 | } |
| 340 | |
Simon Kagstrom | 0347af4 | 2010-03-05 13:42:49 -0800 | [diff] [blame] | 341 | static int lkdtm_register_cpoint(enum cname which) |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 342 | { |
| 343 | int ret; |
| 344 | |
Simon Kagstrom | 0347af4 | 2010-03-05 13:42:49 -0800 | [diff] [blame] | 345 | cpoint = INVALID; |
| 346 | if (lkdtm.entry != NULL) |
| 347 | unregister_jprobe(&lkdtm); |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 348 | |
Simon Kagstrom | 0347af4 | 2010-03-05 13:42:49 -0800 | [diff] [blame] | 349 | switch (which) { |
| 350 | case DIRECT: |
| 351 | lkdtm_do_action(cptype); |
| 352 | return 0; |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 353 | case INT_HARDWARE_ENTRY: |
M. Mohan Kumar | f58f2fa | 2009-09-22 16:43:29 -0700 | [diff] [blame] | 354 | lkdtm.kp.symbol_name = "do_IRQ"; |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 355 | lkdtm.entry = (kprobe_opcode_t*) jp_do_irq; |
| 356 | break; |
| 357 | case INT_HW_IRQ_EN: |
| 358 | lkdtm.kp.symbol_name = "handle_IRQ_event"; |
| 359 | lkdtm.entry = (kprobe_opcode_t*) jp_handle_irq_event; |
| 360 | break; |
| 361 | case INT_TASKLET_ENTRY: |
| 362 | lkdtm.kp.symbol_name = "tasklet_action"; |
| 363 | lkdtm.entry = (kprobe_opcode_t*) jp_tasklet_action; |
| 364 | break; |
| 365 | case FS_DEVRW: |
| 366 | lkdtm.kp.symbol_name = "ll_rw_block"; |
| 367 | lkdtm.entry = (kprobe_opcode_t*) jp_ll_rw_block; |
| 368 | break; |
| 369 | case MEM_SWAPOUT: |
Ankita Garg | 18a61e4 | 2006-11-05 23:52:07 -0800 | [diff] [blame] | 370 | lkdtm.kp.symbol_name = "shrink_inactive_list"; |
| 371 | lkdtm.entry = (kprobe_opcode_t*) jp_shrink_inactive_list; |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 372 | break; |
| 373 | case TIMERADD: |
| 374 | lkdtm.kp.symbol_name = "hrtimer_start"; |
| 375 | lkdtm.entry = (kprobe_opcode_t*) jp_hrtimer_start; |
| 376 | break; |
| 377 | case SCSI_DISPATCH_CMD: |
| 378 | lkdtm.kp.symbol_name = "scsi_dispatch_cmd"; |
| 379 | lkdtm.entry = (kprobe_opcode_t*) jp_scsi_dispatch_cmd; |
| 380 | break; |
| 381 | case IDE_CORE_CP: |
| 382 | #ifdef CONFIG_IDE |
| 383 | lkdtm.kp.symbol_name = "generic_ide_ioctl"; |
| 384 | lkdtm.entry = (kprobe_opcode_t*) jp_generic_ide_ioctl; |
| 385 | #else |
Simon Kagstrom | 0347af4 | 2010-03-05 13:42:49 -0800 | [diff] [blame] | 386 | printk(KERN_INFO "lkdtm: Crash point not available\n"); |
| 387 | return -EINVAL; |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 388 | #endif |
| 389 | break; |
| 390 | default: |
Simon Kagstrom | 0347af4 | 2010-03-05 13:42:49 -0800 | [diff] [blame] | 391 | printk(KERN_INFO "lkdtm: Invalid Crash Point\n"); |
| 392 | return -EINVAL; |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 393 | } |
| 394 | |
Simon Kagstrom | 0347af4 | 2010-03-05 13:42:49 -0800 | [diff] [blame] | 395 | cpoint = which; |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 396 | if ((ret = register_jprobe(&lkdtm)) < 0) { |
Simon Kagstrom | 0347af4 | 2010-03-05 13:42:49 -0800 | [diff] [blame] | 397 | printk(KERN_INFO "lkdtm: Couldn't register jprobe\n"); |
| 398 | cpoint = INVALID; |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 399 | } |
| 400 | |
Simon Kagstrom | 0347af4 | 2010-03-05 13:42:49 -0800 | [diff] [blame] | 401 | return ret; |
| 402 | } |
| 403 | |
| 404 | static ssize_t do_register_entry(enum cname which, struct file *f, |
| 405 | const char __user *user_buf, size_t count, loff_t *off) |
| 406 | { |
| 407 | char *buf; |
| 408 | int err; |
| 409 | |
| 410 | if (count >= PAGE_SIZE) |
| 411 | return -EINVAL; |
| 412 | |
| 413 | buf = (char *)__get_free_page(GFP_KERNEL); |
| 414 | if (!buf) |
| 415 | return -ENOMEM; |
| 416 | if (copy_from_user(buf, user_buf, count)) { |
| 417 | free_page((unsigned long) buf); |
| 418 | return -EFAULT; |
| 419 | } |
| 420 | /* NULL-terminate and remove enter */ |
| 421 | buf[count] = '\0'; |
| 422 | strim(buf); |
| 423 | |
| 424 | cptype = parse_cp_type(buf, count); |
| 425 | free_page((unsigned long) buf); |
| 426 | |
| 427 | if (cptype == NONE) |
| 428 | return -EINVAL; |
| 429 | |
| 430 | err = lkdtm_register_cpoint(which); |
| 431 | if (err < 0) |
| 432 | return err; |
| 433 | |
| 434 | *off += count; |
| 435 | |
| 436 | return count; |
| 437 | } |
| 438 | |
| 439 | /* Generic read callback that just prints out the available crash types */ |
| 440 | static ssize_t lkdtm_debugfs_read(struct file *f, char __user *user_buf, |
| 441 | size_t count, loff_t *off) |
| 442 | { |
| 443 | char *buf; |
| 444 | int i, n, out; |
| 445 | |
| 446 | buf = (char *)__get_free_page(GFP_KERNEL); |
| 447 | |
| 448 | n = snprintf(buf, PAGE_SIZE, "Available crash types:\n"); |
| 449 | for (i = 0; i < ARRAY_SIZE(cp_type); i++) |
| 450 | n += snprintf(buf + n, PAGE_SIZE - n, "%s\n", cp_type[i]); |
| 451 | buf[n] = '\0'; |
| 452 | |
| 453 | out = simple_read_from_buffer(user_buf, count, off, |
| 454 | buf, n); |
| 455 | free_page((unsigned long) buf); |
| 456 | |
| 457 | return out; |
| 458 | } |
| 459 | |
| 460 | static int lkdtm_debugfs_open(struct inode *inode, struct file *file) |
| 461 | { |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 462 | return 0; |
| 463 | } |
| 464 | |
Simon Kagstrom | 0347af4 | 2010-03-05 13:42:49 -0800 | [diff] [blame] | 465 | |
| 466 | static ssize_t int_hardware_entry(struct file *f, const char __user *buf, |
| 467 | size_t count, loff_t *off) |
| 468 | { |
| 469 | return do_register_entry(INT_HARDWARE_ENTRY, f, buf, count, off); |
| 470 | } |
| 471 | |
| 472 | static ssize_t int_hw_irq_en(struct file *f, const char __user *buf, |
| 473 | size_t count, loff_t *off) |
| 474 | { |
| 475 | return do_register_entry(INT_HW_IRQ_EN, f, buf, count, off); |
| 476 | } |
| 477 | |
| 478 | static ssize_t int_tasklet_entry(struct file *f, const char __user *buf, |
| 479 | size_t count, loff_t *off) |
| 480 | { |
| 481 | return do_register_entry(INT_TASKLET_ENTRY, f, buf, count, off); |
| 482 | } |
| 483 | |
| 484 | static ssize_t fs_devrw_entry(struct file *f, const char __user *buf, |
| 485 | size_t count, loff_t *off) |
| 486 | { |
| 487 | return do_register_entry(FS_DEVRW, f, buf, count, off); |
| 488 | } |
| 489 | |
| 490 | static ssize_t mem_swapout_entry(struct file *f, const char __user *buf, |
| 491 | size_t count, loff_t *off) |
| 492 | { |
| 493 | return do_register_entry(MEM_SWAPOUT, f, buf, count, off); |
| 494 | } |
| 495 | |
| 496 | static ssize_t timeradd_entry(struct file *f, const char __user *buf, |
| 497 | size_t count, loff_t *off) |
| 498 | { |
| 499 | return do_register_entry(TIMERADD, f, buf, count, off); |
| 500 | } |
| 501 | |
| 502 | static ssize_t scsi_dispatch_cmd_entry(struct file *f, |
| 503 | const char __user *buf, size_t count, loff_t *off) |
| 504 | { |
| 505 | return do_register_entry(SCSI_DISPATCH_CMD, f, buf, count, off); |
| 506 | } |
| 507 | |
| 508 | static ssize_t ide_core_cp_entry(struct file *f, const char __user *buf, |
| 509 | size_t count, loff_t *off) |
| 510 | { |
| 511 | return do_register_entry(IDE_CORE_CP, f, buf, count, off); |
| 512 | } |
| 513 | |
| 514 | /* Special entry to just crash directly. Available without KPROBEs */ |
| 515 | static ssize_t direct_entry(struct file *f, const char __user *user_buf, |
| 516 | size_t count, loff_t *off) |
| 517 | { |
| 518 | enum ctype type; |
| 519 | char *buf; |
| 520 | |
| 521 | if (count >= PAGE_SIZE) |
| 522 | return -EINVAL; |
| 523 | if (count < 1) |
| 524 | return -EINVAL; |
| 525 | |
| 526 | buf = (char *)__get_free_page(GFP_KERNEL); |
| 527 | if (!buf) |
| 528 | return -ENOMEM; |
| 529 | if (copy_from_user(buf, user_buf, count)) { |
| 530 | free_page((unsigned long) buf); |
| 531 | return -EFAULT; |
| 532 | } |
| 533 | /* NULL-terminate and remove enter */ |
| 534 | buf[count] = '\0'; |
| 535 | strim(buf); |
| 536 | |
| 537 | type = parse_cp_type(buf, count); |
| 538 | free_page((unsigned long) buf); |
| 539 | if (type == NONE) |
| 540 | return -EINVAL; |
| 541 | |
| 542 | printk(KERN_INFO "lkdtm: Performing direct entry %s\n", |
| 543 | cp_type_to_str(type)); |
| 544 | lkdtm_do_action(type); |
| 545 | *off += count; |
| 546 | |
| 547 | return count; |
| 548 | } |
| 549 | |
| 550 | struct crash_entry { |
| 551 | const char *name; |
| 552 | const struct file_operations fops; |
| 553 | }; |
| 554 | |
| 555 | static const struct crash_entry crash_entries[] = { |
| 556 | {"DIRECT", {.read = lkdtm_debugfs_read, |
| 557 | .open = lkdtm_debugfs_open, |
| 558 | .write = direct_entry} }, |
| 559 | {"INT_HARDWARE_ENTRY", {.read = lkdtm_debugfs_read, |
| 560 | .open = lkdtm_debugfs_open, |
| 561 | .write = int_hardware_entry} }, |
| 562 | {"INT_HW_IRQ_EN", {.read = lkdtm_debugfs_read, |
| 563 | .open = lkdtm_debugfs_open, |
| 564 | .write = int_hw_irq_en} }, |
| 565 | {"INT_TASKLET_ENTRY", {.read = lkdtm_debugfs_read, |
| 566 | .open = lkdtm_debugfs_open, |
| 567 | .write = int_tasklet_entry} }, |
| 568 | {"FS_DEVRW", {.read = lkdtm_debugfs_read, |
| 569 | .open = lkdtm_debugfs_open, |
| 570 | .write = fs_devrw_entry} }, |
| 571 | {"MEM_SWAPOUT", {.read = lkdtm_debugfs_read, |
| 572 | .open = lkdtm_debugfs_open, |
| 573 | .write = mem_swapout_entry} }, |
| 574 | {"TIMERADD", {.read = lkdtm_debugfs_read, |
| 575 | .open = lkdtm_debugfs_open, |
| 576 | .write = timeradd_entry} }, |
| 577 | {"SCSI_DISPATCH_CMD", {.read = lkdtm_debugfs_read, |
| 578 | .open = lkdtm_debugfs_open, |
| 579 | .write = scsi_dispatch_cmd_entry} }, |
| 580 | {"IDE_CORE_CP", {.read = lkdtm_debugfs_read, |
| 581 | .open = lkdtm_debugfs_open, |
| 582 | .write = ide_core_cp_entry} }, |
| 583 | }; |
| 584 | |
| 585 | static struct dentry *lkdtm_debugfs_root; |
| 586 | |
| 587 | static int __init lkdtm_module_init(void) |
| 588 | { |
| 589 | int ret = -EINVAL; |
| 590 | int n_debugfs_entries = 1; /* Assume only the direct entry */ |
| 591 | int i; |
| 592 | |
| 593 | /* Register debugfs interface */ |
| 594 | lkdtm_debugfs_root = debugfs_create_dir("provoke-crash", NULL); |
| 595 | if (!lkdtm_debugfs_root) { |
| 596 | printk(KERN_ERR "lkdtm: creating root dir failed\n"); |
| 597 | return -ENODEV; |
| 598 | } |
| 599 | |
| 600 | #ifdef CONFIG_KPROBES |
| 601 | n_debugfs_entries = ARRAY_SIZE(crash_entries); |
| 602 | #endif |
| 603 | |
| 604 | for (i = 0; i < n_debugfs_entries; i++) { |
| 605 | const struct crash_entry *cur = &crash_entries[i]; |
| 606 | struct dentry *de; |
| 607 | |
| 608 | de = debugfs_create_file(cur->name, 0644, lkdtm_debugfs_root, |
| 609 | NULL, &cur->fops); |
| 610 | if (de == NULL) { |
| 611 | printk(KERN_ERR "lkdtm: could not create %s\n", |
| 612 | cur->name); |
| 613 | goto out_err; |
| 614 | } |
| 615 | } |
| 616 | |
| 617 | if (lkdtm_parse_commandline() == -EINVAL) { |
| 618 | printk(KERN_INFO "lkdtm: Invalid command\n"); |
| 619 | goto out_err; |
| 620 | } |
| 621 | |
| 622 | if (cpoint != INVALID && cptype != NONE) { |
| 623 | ret = lkdtm_register_cpoint(cpoint); |
| 624 | if (ret < 0) { |
| 625 | printk(KERN_INFO "lkdtm: Invalid crash point %d\n", |
| 626 | cpoint); |
| 627 | goto out_err; |
| 628 | } |
| 629 | printk(KERN_INFO "lkdtm: Crash point %s of type %s registered\n", |
| 630 | cpoint_name, cpoint_type); |
| 631 | } else { |
| 632 | printk(KERN_INFO "lkdtm: No crash points registered, enable through debugfs\n"); |
| 633 | } |
| 634 | |
| 635 | return 0; |
| 636 | |
| 637 | out_err: |
| 638 | debugfs_remove_recursive(lkdtm_debugfs_root); |
| 639 | return ret; |
| 640 | } |
| 641 | |
Adrian Bunk | 2118116 | 2008-02-06 01:36:50 -0800 | [diff] [blame] | 642 | static void __exit lkdtm_module_exit(void) |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 643 | { |
Simon Kagstrom | 0347af4 | 2010-03-05 13:42:49 -0800 | [diff] [blame] | 644 | debugfs_remove_recursive(lkdtm_debugfs_root); |
| 645 | |
| 646 | unregister_jprobe(&lkdtm); |
| 647 | printk(KERN_INFO "lkdtm: Crash point unregistered\n"); |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 648 | } |
| 649 | |
| 650 | module_init(lkdtm_module_init); |
| 651 | module_exit(lkdtm_module_exit); |
| 652 | |
| 653 | MODULE_LICENSE("GPL"); |