Commit | Line | Data |
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8bb31b9d AG |
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 | * | |
0347af4e | 29 | * Debugfs support added by Simon Kagstrom <simon.kagstrom@netinsight.net> |
8bb31b9d | 30 | * |
0347af4e | 31 | * See Documentation/fault-injection/provoke-crashes.txt for instructions |
8bb31b9d AG |
32 | */ |
33 | ||
34 | #include <linux/kernel.h> | |
5d861d92 | 35 | #include <linux/fs.h> |
8bb31b9d | 36 | #include <linux/module.h> |
5d861d92 | 37 | #include <linux/buffer_head.h> |
8bb31b9d | 38 | #include <linux/kprobes.h> |
5d861d92 | 39 | #include <linux/list.h> |
8bb31b9d | 40 | #include <linux/init.h> |
8bb31b9d | 41 | #include <linux/interrupt.h> |
5d861d92 | 42 | #include <linux/hrtimer.h> |
5a0e3ad6 | 43 | #include <linux/slab.h> |
8bb31b9d | 44 | #include <scsi/scsi_cmnd.h> |
0347af4e | 45 | #include <linux/debugfs.h> |
cc33c537 | 46 | #include <linux/vmalloc.h> |
8bb31b9d AG |
47 | |
48 | #ifdef CONFIG_IDE | |
49 | #include <linux/ide.h> | |
50 | #endif | |
51 | ||
8bb31b9d AG |
52 | #define DEFAULT_COUNT 10 |
53 | #define REC_NUM_DEFAULT 10 | |
cc33c537 | 54 | #define EXEC_SIZE 64 |
8bb31b9d AG |
55 | |
56 | enum cname { | |
93e2f585 NK |
57 | CN_INVALID, |
58 | CN_INT_HARDWARE_ENTRY, | |
59 | CN_INT_HW_IRQ_EN, | |
60 | CN_INT_TASKLET_ENTRY, | |
61 | CN_FS_DEVRW, | |
62 | CN_MEM_SWAPOUT, | |
63 | CN_TIMERADD, | |
64 | CN_SCSI_DISPATCH_CMD, | |
65 | CN_IDE_CORE_CP, | |
66 | CN_DIRECT, | |
8bb31b9d AG |
67 | }; |
68 | ||
69 | enum ctype { | |
93e2f585 NK |
70 | CT_NONE, |
71 | CT_PANIC, | |
72 | CT_BUG, | |
65892723 | 73 | CT_WARNING, |
93e2f585 NK |
74 | CT_EXCEPTION, |
75 | CT_LOOP, | |
76 | CT_OVERFLOW, | |
77 | CT_CORRUPT_STACK, | |
78 | CT_UNALIGNED_LOAD_STORE_WRITE, | |
79 | CT_OVERWRITE_ALLOCATION, | |
80 | CT_WRITE_AFTER_FREE, | |
81 | CT_SOFTLOCKUP, | |
82 | CT_HARDLOCKUP, | |
274a5855 | 83 | CT_SPINLOCKUP, |
93e2f585 | 84 | CT_HUNG_TASK, |
cc33c537 KC |
85 | CT_EXEC_DATA, |
86 | CT_EXEC_STACK, | |
87 | CT_EXEC_KMALLOC, | |
88 | CT_EXEC_VMALLOC, | |
8bb31b9d AG |
89 | }; |
90 | ||
91 | static char* cp_name[] = { | |
92 | "INT_HARDWARE_ENTRY", | |
93 | "INT_HW_IRQ_EN", | |
94 | "INT_TASKLET_ENTRY", | |
95 | "FS_DEVRW", | |
96 | "MEM_SWAPOUT", | |
97 | "TIMERADD", | |
98 | "SCSI_DISPATCH_CMD", | |
0347af4e SK |
99 | "IDE_CORE_CP", |
100 | "DIRECT", | |
8bb31b9d AG |
101 | }; |
102 | ||
103 | static char* cp_type[] = { | |
104 | "PANIC", | |
105 | "BUG", | |
65892723 | 106 | "WARNING", |
8bb31b9d AG |
107 | "EXCEPTION", |
108 | "LOOP", | |
0347af4e SK |
109 | "OVERFLOW", |
110 | "CORRUPT_STACK", | |
111 | "UNALIGNED_LOAD_STORE_WRITE", | |
112 | "OVERWRITE_ALLOCATION", | |
113 | "WRITE_AFTER_FREE", | |
a48223f9 FW |
114 | "SOFTLOCKUP", |
115 | "HARDLOCKUP", | |
274a5855 | 116 | "SPINLOCKUP", |
a48223f9 | 117 | "HUNG_TASK", |
cc33c537 KC |
118 | "EXEC_DATA", |
119 | "EXEC_STACK", | |
120 | "EXEC_KMALLOC", | |
121 | "EXEC_VMALLOC", | |
8bb31b9d AG |
122 | }; |
123 | ||
124 | static struct jprobe lkdtm; | |
125 | ||
126 | static int lkdtm_parse_commandline(void); | |
127 | static void lkdtm_handler(void); | |
128 | ||
ec1c620b AV |
129 | static char* cpoint_name; |
130 | static char* cpoint_type; | |
8bb31b9d AG |
131 | static int cpoint_count = DEFAULT_COUNT; |
132 | static int recur_count = REC_NUM_DEFAULT; | |
133 | ||
93e2f585 NK |
134 | static enum cname cpoint = CN_INVALID; |
135 | static enum ctype cptype = CT_NONE; | |
8bb31b9d | 136 | static int count = DEFAULT_COUNT; |
aa2c96d6 | 137 | static DEFINE_SPINLOCK(count_lock); |
274a5855 | 138 | static DEFINE_SPINLOCK(lock_me_up); |
8bb31b9d | 139 | |
cc33c537 KC |
140 | static u8 data_area[EXEC_SIZE]; |
141 | ||
8bb31b9d | 142 | module_param(recur_count, int, 0644); |
5d861d92 RD |
143 | MODULE_PARM_DESC(recur_count, " Recursion level for the stack overflow test, "\ |
144 | "default is 10"); | |
dca41306 | 145 | module_param(cpoint_name, charp, 0444); |
5d861d92 | 146 | MODULE_PARM_DESC(cpoint_name, " Crash Point, where kernel is to be crashed"); |
dca41306 | 147 | module_param(cpoint_type, charp, 0444); |
5d861d92 RD |
148 | MODULE_PARM_DESC(cpoint_type, " Crash Point Type, action to be taken on "\ |
149 | "hitting the crash point"); | |
150 | module_param(cpoint_count, int, 0644); | |
151 | MODULE_PARM_DESC(cpoint_count, " Crash Point Count, number of times the "\ | |
152 | "crash point is to be hit to trigger action"); | |
8bb31b9d | 153 | |
2118116e | 154 | static unsigned int jp_do_irq(unsigned int irq) |
8bb31b9d AG |
155 | { |
156 | lkdtm_handler(); | |
157 | jprobe_return(); | |
158 | return 0; | |
159 | } | |
160 | ||
2118116e AB |
161 | static irqreturn_t jp_handle_irq_event(unsigned int irq, |
162 | struct irqaction *action) | |
8bb31b9d AG |
163 | { |
164 | lkdtm_handler(); | |
165 | jprobe_return(); | |
166 | return 0; | |
167 | } | |
168 | ||
2118116e | 169 | static void jp_tasklet_action(struct softirq_action *a) |
8bb31b9d AG |
170 | { |
171 | lkdtm_handler(); | |
172 | jprobe_return(); | |
173 | } | |
174 | ||
2118116e | 175 | static void jp_ll_rw_block(int rw, int nr, struct buffer_head *bhs[]) |
8bb31b9d AG |
176 | { |
177 | lkdtm_handler(); | |
178 | jprobe_return(); | |
179 | } | |
180 | ||
181 | struct scan_control; | |
182 | ||
2118116e AB |
183 | static unsigned long jp_shrink_inactive_list(unsigned long max_scan, |
184 | struct zone *zone, | |
185 | struct scan_control *sc) | |
8bb31b9d AG |
186 | { |
187 | lkdtm_handler(); | |
188 | jprobe_return(); | |
189 | return 0; | |
190 | } | |
191 | ||
2118116e AB |
192 | static int jp_hrtimer_start(struct hrtimer *timer, ktime_t tim, |
193 | const enum hrtimer_mode mode) | |
8bb31b9d AG |
194 | { |
195 | lkdtm_handler(); | |
196 | jprobe_return(); | |
197 | return 0; | |
198 | } | |
199 | ||
2118116e | 200 | static int jp_scsi_dispatch_cmd(struct scsi_cmnd *cmd) |
8bb31b9d AG |
201 | { |
202 | lkdtm_handler(); | |
203 | jprobe_return(); | |
204 | return 0; | |
205 | } | |
206 | ||
207 | #ifdef CONFIG_IDE | |
208 | int jp_generic_ide_ioctl(ide_drive_t *drive, struct file *file, | |
209 | struct block_device *bdev, unsigned int cmd, | |
210 | unsigned long arg) | |
211 | { | |
212 | lkdtm_handler(); | |
213 | jprobe_return(); | |
214 | return 0; | |
215 | } | |
216 | #endif | |
217 | ||
0347af4e SK |
218 | /* Return the crashpoint number or NONE if the name is invalid */ |
219 | static enum ctype parse_cp_type(const char *what, size_t count) | |
220 | { | |
221 | int i; | |
222 | ||
223 | for (i = 0; i < ARRAY_SIZE(cp_type); i++) { | |
224 | if (!strcmp(what, cp_type[i])) | |
225 | return i + 1; | |
226 | } | |
227 | ||
93e2f585 | 228 | return CT_NONE; |
0347af4e SK |
229 | } |
230 | ||
231 | static const char *cp_type_to_str(enum ctype type) | |
232 | { | |
93e2f585 | 233 | if (type == CT_NONE || type < 0 || type > ARRAY_SIZE(cp_type)) |
0347af4e SK |
234 | return "None"; |
235 | ||
236 | return cp_type[type - 1]; | |
237 | } | |
238 | ||
239 | static const char *cp_name_to_str(enum cname name) | |
240 | { | |
93e2f585 | 241 | if (name == CN_INVALID || name < 0 || name > ARRAY_SIZE(cp_name)) |
0347af4e SK |
242 | return "INVALID"; |
243 | ||
244 | return cp_name[name - 1]; | |
245 | } | |
246 | ||
247 | ||
8bb31b9d AG |
248 | static int lkdtm_parse_commandline(void) |
249 | { | |
250 | int i; | |
aa2c96d6 | 251 | unsigned long flags; |
8bb31b9d | 252 | |
0347af4e | 253 | if (cpoint_count < 1 || recur_count < 1) |
8bb31b9d AG |
254 | return -EINVAL; |
255 | ||
aa2c96d6 | 256 | spin_lock_irqsave(&count_lock, flags); |
0347af4e | 257 | count = cpoint_count; |
aa2c96d6 | 258 | spin_unlock_irqrestore(&count_lock, flags); |
0347af4e SK |
259 | |
260 | /* No special parameters */ | |
261 | if (!cpoint_type && !cpoint_name) | |
262 | return 0; | |
263 | ||
264 | /* Neither or both of these need to be set */ | |
265 | if (!cpoint_type || !cpoint_name) | |
266 | return -EINVAL; | |
267 | ||
268 | cptype = parse_cp_type(cpoint_type, strlen(cpoint_type)); | |
93e2f585 | 269 | if (cptype == CT_NONE) |
0347af4e SK |
270 | return -EINVAL; |
271 | ||
272 | for (i = 0; i < ARRAY_SIZE(cp_name); i++) { | |
8bb31b9d AG |
273 | if (!strcmp(cpoint_name, cp_name[i])) { |
274 | cpoint = i + 1; | |
0347af4e | 275 | return 0; |
8bb31b9d AG |
276 | } |
277 | } | |
278 | ||
0347af4e SK |
279 | /* Could not find a valid crash point */ |
280 | return -EINVAL; | |
8bb31b9d AG |
281 | } |
282 | ||
283 | static int recursive_loop(int a) | |
284 | { | |
285 | char buf[1024]; | |
286 | ||
287 | memset(buf,0xFF,1024); | |
288 | recur_count--; | |
289 | if (!recur_count) | |
290 | return 0; | |
291 | else | |
292 | return recursive_loop(a); | |
293 | } | |
294 | ||
cc33c537 KC |
295 | static void do_nothing(void) |
296 | { | |
297 | return; | |
298 | } | |
299 | ||
300 | static void execute_location(void *dst) | |
301 | { | |
302 | void (*func)(void) = dst; | |
303 | ||
304 | memcpy(dst, do_nothing, EXEC_SIZE); | |
305 | func(); | |
306 | } | |
307 | ||
0347af4e | 308 | static void lkdtm_do_action(enum ctype which) |
8bb31b9d | 309 | { |
0347af4e | 310 | switch (which) { |
93e2f585 | 311 | case CT_PANIC: |
0347af4e SK |
312 | panic("dumptest"); |
313 | break; | |
93e2f585 | 314 | case CT_BUG: |
0347af4e SK |
315 | BUG(); |
316 | break; | |
65892723 KC |
317 | case CT_WARNING: |
318 | WARN_ON(1); | |
319 | break; | |
93e2f585 | 320 | case CT_EXCEPTION: |
0347af4e SK |
321 | *((int *) 0) = 0; |
322 | break; | |
93e2f585 | 323 | case CT_LOOP: |
0347af4e SK |
324 | for (;;) |
325 | ; | |
326 | break; | |
93e2f585 | 327 | case CT_OVERFLOW: |
0347af4e SK |
328 | (void) recursive_loop(0); |
329 | break; | |
93e2f585 | 330 | case CT_CORRUPT_STACK: { |
4f198289 KC |
331 | /* Make sure the compiler creates and uses an 8 char array. */ |
332 | volatile char data[8]; | |
0347af4e | 333 | |
4f198289 | 334 | memset((void *)data, 0, 64); |
0347af4e SK |
335 | break; |
336 | } | |
93e2f585 | 337 | case CT_UNALIGNED_LOAD_STORE_WRITE: { |
0347af4e SK |
338 | static u8 data[5] __attribute__((aligned(4))) = {1, 2, |
339 | 3, 4, 5}; | |
340 | u32 *p; | |
341 | u32 val = 0x12345678; | |
342 | ||
343 | p = (u32 *)(data + 1); | |
344 | if (*p == 0) | |
345 | val = 0x87654321; | |
346 | *p = val; | |
347 | break; | |
348 | } | |
93e2f585 | 349 | case CT_OVERWRITE_ALLOCATION: { |
0347af4e SK |
350 | size_t len = 1020; |
351 | u32 *data = kmalloc(len, GFP_KERNEL); | |
352 | ||
353 | data[1024 / sizeof(u32)] = 0x12345678; | |
354 | kfree(data); | |
355 | break; | |
356 | } | |
93e2f585 | 357 | case CT_WRITE_AFTER_FREE: { |
0347af4e SK |
358 | size_t len = 1024; |
359 | u32 *data = kmalloc(len, GFP_KERNEL); | |
360 | ||
361 | kfree(data); | |
362 | schedule(); | |
363 | memset(data, 0x78, len); | |
364 | break; | |
365 | } | |
93e2f585 | 366 | case CT_SOFTLOCKUP: |
a48223f9 FW |
367 | preempt_disable(); |
368 | for (;;) | |
369 | cpu_relax(); | |
370 | break; | |
93e2f585 | 371 | case CT_HARDLOCKUP: |
a48223f9 FW |
372 | local_irq_disable(); |
373 | for (;;) | |
374 | cpu_relax(); | |
375 | break; | |
274a5855 KC |
376 | case CT_SPINLOCKUP: |
377 | /* Must be called twice to trigger. */ | |
378 | spin_lock(&lock_me_up); | |
379 | break; | |
93e2f585 | 380 | case CT_HUNG_TASK: |
a48223f9 FW |
381 | set_current_state(TASK_UNINTERRUPTIBLE); |
382 | schedule(); | |
383 | break; | |
cc33c537 KC |
384 | case CT_EXEC_DATA: |
385 | execute_location(data_area); | |
386 | break; | |
387 | case CT_EXEC_STACK: { | |
388 | u8 stack_area[EXEC_SIZE]; | |
389 | execute_location(stack_area); | |
390 | break; | |
391 | } | |
392 | case CT_EXEC_KMALLOC: { | |
393 | u32 *kmalloc_area = kmalloc(EXEC_SIZE, GFP_KERNEL); | |
394 | execute_location(kmalloc_area); | |
395 | kfree(kmalloc_area); | |
396 | break; | |
397 | } | |
398 | case CT_EXEC_VMALLOC: { | |
399 | u32 *vmalloc_area = vmalloc(EXEC_SIZE); | |
400 | execute_location(vmalloc_area); | |
401 | vfree(vmalloc_area); | |
402 | break; | |
403 | } | |
93e2f585 | 404 | case CT_NONE: |
0347af4e SK |
405 | default: |
406 | break; | |
407 | } | |
408 | ||
409 | } | |
410 | ||
411 | static void lkdtm_handler(void) | |
412 | { | |
aa2c96d6 | 413 | unsigned long flags; |
92618184 | 414 | bool do_it = false; |
aa2c96d6 JH |
415 | |
416 | spin_lock_irqsave(&count_lock, flags); | |
0347af4e SK |
417 | count--; |
418 | printk(KERN_INFO "lkdtm: Crash point %s of type %s hit, trigger in %d rounds\n", | |
419 | cp_name_to_str(cpoint), cp_type_to_str(cptype), count); | |
8bb31b9d AG |
420 | |
421 | if (count == 0) { | |
92618184 | 422 | do_it = true; |
8bb31b9d AG |
423 | count = cpoint_count; |
424 | } | |
aa2c96d6 | 425 | spin_unlock_irqrestore(&count_lock, flags); |
92618184 CW |
426 | |
427 | if (do_it) | |
428 | lkdtm_do_action(cptype); | |
8bb31b9d AG |
429 | } |
430 | ||
0347af4e | 431 | static int lkdtm_register_cpoint(enum cname which) |
8bb31b9d AG |
432 | { |
433 | int ret; | |
434 | ||
93e2f585 | 435 | cpoint = CN_INVALID; |
0347af4e SK |
436 | if (lkdtm.entry != NULL) |
437 | unregister_jprobe(&lkdtm); | |
8bb31b9d | 438 | |
0347af4e | 439 | switch (which) { |
93e2f585 | 440 | case CN_DIRECT: |
0347af4e SK |
441 | lkdtm_do_action(cptype); |
442 | return 0; | |
93e2f585 | 443 | case CN_INT_HARDWARE_ENTRY: |
f58f2fa9 | 444 | lkdtm.kp.symbol_name = "do_IRQ"; |
8bb31b9d AG |
445 | lkdtm.entry = (kprobe_opcode_t*) jp_do_irq; |
446 | break; | |
93e2f585 | 447 | case CN_INT_HW_IRQ_EN: |
8bb31b9d AG |
448 | lkdtm.kp.symbol_name = "handle_IRQ_event"; |
449 | lkdtm.entry = (kprobe_opcode_t*) jp_handle_irq_event; | |
450 | break; | |
93e2f585 | 451 | case CN_INT_TASKLET_ENTRY: |
8bb31b9d AG |
452 | lkdtm.kp.symbol_name = "tasklet_action"; |
453 | lkdtm.entry = (kprobe_opcode_t*) jp_tasklet_action; | |
454 | break; | |
93e2f585 | 455 | case CN_FS_DEVRW: |
8bb31b9d AG |
456 | lkdtm.kp.symbol_name = "ll_rw_block"; |
457 | lkdtm.entry = (kprobe_opcode_t*) jp_ll_rw_block; | |
458 | break; | |
93e2f585 | 459 | case CN_MEM_SWAPOUT: |
18a61e4a AG |
460 | lkdtm.kp.symbol_name = "shrink_inactive_list"; |
461 | lkdtm.entry = (kprobe_opcode_t*) jp_shrink_inactive_list; | |
8bb31b9d | 462 | break; |
93e2f585 | 463 | case CN_TIMERADD: |
8bb31b9d AG |
464 | lkdtm.kp.symbol_name = "hrtimer_start"; |
465 | lkdtm.entry = (kprobe_opcode_t*) jp_hrtimer_start; | |
466 | break; | |
93e2f585 | 467 | case CN_SCSI_DISPATCH_CMD: |
8bb31b9d AG |
468 | lkdtm.kp.symbol_name = "scsi_dispatch_cmd"; |
469 | lkdtm.entry = (kprobe_opcode_t*) jp_scsi_dispatch_cmd; | |
470 | break; | |
93e2f585 | 471 | case CN_IDE_CORE_CP: |
8bb31b9d AG |
472 | #ifdef CONFIG_IDE |
473 | lkdtm.kp.symbol_name = "generic_ide_ioctl"; | |
474 | lkdtm.entry = (kprobe_opcode_t*) jp_generic_ide_ioctl; | |
475 | #else | |
0347af4e SK |
476 | printk(KERN_INFO "lkdtm: Crash point not available\n"); |
477 | return -EINVAL; | |
8bb31b9d AG |
478 | #endif |
479 | break; | |
480 | default: | |
0347af4e SK |
481 | printk(KERN_INFO "lkdtm: Invalid Crash Point\n"); |
482 | return -EINVAL; | |
8bb31b9d AG |
483 | } |
484 | ||
0347af4e | 485 | cpoint = which; |
8bb31b9d | 486 | if ((ret = register_jprobe(&lkdtm)) < 0) { |
0347af4e | 487 | printk(KERN_INFO "lkdtm: Couldn't register jprobe\n"); |
93e2f585 | 488 | cpoint = CN_INVALID; |
0347af4e SK |
489 | } |
490 | ||
491 | return ret; | |
492 | } | |
493 | ||
494 | static ssize_t do_register_entry(enum cname which, struct file *f, | |
495 | const char __user *user_buf, size_t count, loff_t *off) | |
496 | { | |
497 | char *buf; | |
498 | int err; | |
499 | ||
500 | if (count >= PAGE_SIZE) | |
501 | return -EINVAL; | |
502 | ||
503 | buf = (char *)__get_free_page(GFP_KERNEL); | |
504 | if (!buf) | |
505 | return -ENOMEM; | |
506 | if (copy_from_user(buf, user_buf, count)) { | |
507 | free_page((unsigned long) buf); | |
508 | return -EFAULT; | |
509 | } | |
510 | /* NULL-terminate and remove enter */ | |
511 | buf[count] = '\0'; | |
512 | strim(buf); | |
513 | ||
514 | cptype = parse_cp_type(buf, count); | |
515 | free_page((unsigned long) buf); | |
516 | ||
93e2f585 | 517 | if (cptype == CT_NONE) |
0347af4e SK |
518 | return -EINVAL; |
519 | ||
520 | err = lkdtm_register_cpoint(which); | |
521 | if (err < 0) | |
522 | return err; | |
523 | ||
524 | *off += count; | |
525 | ||
526 | return count; | |
527 | } | |
528 | ||
529 | /* Generic read callback that just prints out the available crash types */ | |
530 | static ssize_t lkdtm_debugfs_read(struct file *f, char __user *user_buf, | |
531 | size_t count, loff_t *off) | |
532 | { | |
533 | char *buf; | |
534 | int i, n, out; | |
535 | ||
536 | buf = (char *)__get_free_page(GFP_KERNEL); | |
086ff4b3 AC |
537 | if (buf == NULL) |
538 | return -ENOMEM; | |
0347af4e SK |
539 | |
540 | n = snprintf(buf, PAGE_SIZE, "Available crash types:\n"); | |
541 | for (i = 0; i < ARRAY_SIZE(cp_type); i++) | |
542 | n += snprintf(buf + n, PAGE_SIZE - n, "%s\n", cp_type[i]); | |
543 | buf[n] = '\0'; | |
544 | ||
545 | out = simple_read_from_buffer(user_buf, count, off, | |
546 | buf, n); | |
547 | free_page((unsigned long) buf); | |
548 | ||
549 | return out; | |
550 | } | |
551 | ||
552 | static int lkdtm_debugfs_open(struct inode *inode, struct file *file) | |
553 | { | |
554 | return 0; | |
555 | } | |
556 | ||
557 | ||
558 | static ssize_t int_hardware_entry(struct file *f, const char __user *buf, | |
559 | size_t count, loff_t *off) | |
560 | { | |
93e2f585 | 561 | return do_register_entry(CN_INT_HARDWARE_ENTRY, f, buf, count, off); |
0347af4e SK |
562 | } |
563 | ||
564 | static ssize_t int_hw_irq_en(struct file *f, const char __user *buf, | |
565 | size_t count, loff_t *off) | |
566 | { | |
93e2f585 | 567 | return do_register_entry(CN_INT_HW_IRQ_EN, f, buf, count, off); |
0347af4e SK |
568 | } |
569 | ||
570 | static ssize_t int_tasklet_entry(struct file *f, const char __user *buf, | |
571 | size_t count, loff_t *off) | |
572 | { | |
93e2f585 | 573 | return do_register_entry(CN_INT_TASKLET_ENTRY, f, buf, count, off); |
0347af4e SK |
574 | } |
575 | ||
576 | static ssize_t fs_devrw_entry(struct file *f, const char __user *buf, | |
577 | size_t count, loff_t *off) | |
578 | { | |
93e2f585 | 579 | return do_register_entry(CN_FS_DEVRW, f, buf, count, off); |
0347af4e SK |
580 | } |
581 | ||
582 | static ssize_t mem_swapout_entry(struct file *f, const char __user *buf, | |
583 | size_t count, loff_t *off) | |
584 | { | |
93e2f585 | 585 | return do_register_entry(CN_MEM_SWAPOUT, f, buf, count, off); |
0347af4e SK |
586 | } |
587 | ||
588 | static ssize_t timeradd_entry(struct file *f, const char __user *buf, | |
589 | size_t count, loff_t *off) | |
590 | { | |
93e2f585 | 591 | return do_register_entry(CN_TIMERADD, f, buf, count, off); |
0347af4e SK |
592 | } |
593 | ||
594 | static ssize_t scsi_dispatch_cmd_entry(struct file *f, | |
595 | const char __user *buf, size_t count, loff_t *off) | |
596 | { | |
93e2f585 | 597 | return do_register_entry(CN_SCSI_DISPATCH_CMD, f, buf, count, off); |
0347af4e SK |
598 | } |
599 | ||
600 | static ssize_t ide_core_cp_entry(struct file *f, const char __user *buf, | |
601 | size_t count, loff_t *off) | |
602 | { | |
93e2f585 | 603 | return do_register_entry(CN_IDE_CORE_CP, f, buf, count, off); |
0347af4e SK |
604 | } |
605 | ||
606 | /* Special entry to just crash directly. Available without KPROBEs */ | |
607 | static ssize_t direct_entry(struct file *f, const char __user *user_buf, | |
608 | size_t count, loff_t *off) | |
609 | { | |
610 | enum ctype type; | |
611 | char *buf; | |
612 | ||
613 | if (count >= PAGE_SIZE) | |
614 | return -EINVAL; | |
615 | if (count < 1) | |
616 | return -EINVAL; | |
617 | ||
618 | buf = (char *)__get_free_page(GFP_KERNEL); | |
619 | if (!buf) | |
620 | return -ENOMEM; | |
621 | if (copy_from_user(buf, user_buf, count)) { | |
622 | free_page((unsigned long) buf); | |
623 | return -EFAULT; | |
624 | } | |
625 | /* NULL-terminate and remove enter */ | |
626 | buf[count] = '\0'; | |
627 | strim(buf); | |
628 | ||
629 | type = parse_cp_type(buf, count); | |
630 | free_page((unsigned long) buf); | |
93e2f585 | 631 | if (type == CT_NONE) |
0347af4e SK |
632 | return -EINVAL; |
633 | ||
634 | printk(KERN_INFO "lkdtm: Performing direct entry %s\n", | |
635 | cp_type_to_str(type)); | |
636 | lkdtm_do_action(type); | |
637 | *off += count; | |
638 | ||
639 | return count; | |
640 | } | |
641 | ||
642 | struct crash_entry { | |
643 | const char *name; | |
644 | const struct file_operations fops; | |
645 | }; | |
646 | ||
647 | static const struct crash_entry crash_entries[] = { | |
648 | {"DIRECT", {.read = lkdtm_debugfs_read, | |
05271ec4 | 649 | .llseek = generic_file_llseek, |
0347af4e SK |
650 | .open = lkdtm_debugfs_open, |
651 | .write = direct_entry} }, | |
652 | {"INT_HARDWARE_ENTRY", {.read = lkdtm_debugfs_read, | |
05271ec4 | 653 | .llseek = generic_file_llseek, |
0347af4e SK |
654 | .open = lkdtm_debugfs_open, |
655 | .write = int_hardware_entry} }, | |
656 | {"INT_HW_IRQ_EN", {.read = lkdtm_debugfs_read, | |
05271ec4 | 657 | .llseek = generic_file_llseek, |
0347af4e SK |
658 | .open = lkdtm_debugfs_open, |
659 | .write = int_hw_irq_en} }, | |
660 | {"INT_TASKLET_ENTRY", {.read = lkdtm_debugfs_read, | |
05271ec4 | 661 | .llseek = generic_file_llseek, |
0347af4e SK |
662 | .open = lkdtm_debugfs_open, |
663 | .write = int_tasklet_entry} }, | |
664 | {"FS_DEVRW", {.read = lkdtm_debugfs_read, | |
05271ec4 | 665 | .llseek = generic_file_llseek, |
0347af4e SK |
666 | .open = lkdtm_debugfs_open, |
667 | .write = fs_devrw_entry} }, | |
668 | {"MEM_SWAPOUT", {.read = lkdtm_debugfs_read, | |
05271ec4 | 669 | .llseek = generic_file_llseek, |
0347af4e SK |
670 | .open = lkdtm_debugfs_open, |
671 | .write = mem_swapout_entry} }, | |
672 | {"TIMERADD", {.read = lkdtm_debugfs_read, | |
05271ec4 | 673 | .llseek = generic_file_llseek, |
0347af4e SK |
674 | .open = lkdtm_debugfs_open, |
675 | .write = timeradd_entry} }, | |
676 | {"SCSI_DISPATCH_CMD", {.read = lkdtm_debugfs_read, | |
05271ec4 | 677 | .llseek = generic_file_llseek, |
0347af4e SK |
678 | .open = lkdtm_debugfs_open, |
679 | .write = scsi_dispatch_cmd_entry} }, | |
680 | {"IDE_CORE_CP", {.read = lkdtm_debugfs_read, | |
05271ec4 | 681 | .llseek = generic_file_llseek, |
0347af4e SK |
682 | .open = lkdtm_debugfs_open, |
683 | .write = ide_core_cp_entry} }, | |
684 | }; | |
685 | ||
686 | static struct dentry *lkdtm_debugfs_root; | |
687 | ||
688 | static int __init lkdtm_module_init(void) | |
689 | { | |
690 | int ret = -EINVAL; | |
691 | int n_debugfs_entries = 1; /* Assume only the direct entry */ | |
692 | int i; | |
693 | ||
694 | /* Register debugfs interface */ | |
695 | lkdtm_debugfs_root = debugfs_create_dir("provoke-crash", NULL); | |
696 | if (!lkdtm_debugfs_root) { | |
697 | printk(KERN_ERR "lkdtm: creating root dir failed\n"); | |
698 | return -ENODEV; | |
699 | } | |
700 | ||
701 | #ifdef CONFIG_KPROBES | |
702 | n_debugfs_entries = ARRAY_SIZE(crash_entries); | |
703 | #endif | |
704 | ||
705 | for (i = 0; i < n_debugfs_entries; i++) { | |
706 | const struct crash_entry *cur = &crash_entries[i]; | |
707 | struct dentry *de; | |
708 | ||
709 | de = debugfs_create_file(cur->name, 0644, lkdtm_debugfs_root, | |
710 | NULL, &cur->fops); | |
711 | if (de == NULL) { | |
712 | printk(KERN_ERR "lkdtm: could not create %s\n", | |
713 | cur->name); | |
714 | goto out_err; | |
715 | } | |
716 | } | |
717 | ||
718 | if (lkdtm_parse_commandline() == -EINVAL) { | |
719 | printk(KERN_INFO "lkdtm: Invalid command\n"); | |
720 | goto out_err; | |
721 | } | |
722 | ||
93e2f585 | 723 | if (cpoint != CN_INVALID && cptype != CT_NONE) { |
0347af4e SK |
724 | ret = lkdtm_register_cpoint(cpoint); |
725 | if (ret < 0) { | |
726 | printk(KERN_INFO "lkdtm: Invalid crash point %d\n", | |
727 | cpoint); | |
728 | goto out_err; | |
729 | } | |
730 | printk(KERN_INFO "lkdtm: Crash point %s of type %s registered\n", | |
731 | cpoint_name, cpoint_type); | |
732 | } else { | |
733 | printk(KERN_INFO "lkdtm: No crash points registered, enable through debugfs\n"); | |
8bb31b9d AG |
734 | } |
735 | ||
8bb31b9d | 736 | return 0; |
0347af4e SK |
737 | |
738 | out_err: | |
739 | debugfs_remove_recursive(lkdtm_debugfs_root); | |
740 | return ret; | |
8bb31b9d AG |
741 | } |
742 | ||
2118116e | 743 | static void __exit lkdtm_module_exit(void) |
8bb31b9d | 744 | { |
0347af4e SK |
745 | debugfs_remove_recursive(lkdtm_debugfs_root); |
746 | ||
747 | unregister_jprobe(&lkdtm); | |
748 | printk(KERN_INFO "lkdtm: Crash point unregistered\n"); | |
8bb31b9d AG |
749 | } |
750 | ||
751 | module_init(lkdtm_module_init); | |
752 | module_exit(lkdtm_module_exit); | |
753 | ||
754 | MODULE_LICENSE("GPL"); |