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> |
8bb31b9d AG |
46 | |
47 | #ifdef CONFIG_IDE | |
48 | #include <linux/ide.h> | |
49 | #endif | |
50 | ||
8bb31b9d AG |
51 | #define DEFAULT_COUNT 10 |
52 | #define REC_NUM_DEFAULT 10 | |
53 | ||
54 | enum cname { | |
93e2f585 NK |
55 | CN_INVALID, |
56 | CN_INT_HARDWARE_ENTRY, | |
57 | CN_INT_HW_IRQ_EN, | |
58 | CN_INT_TASKLET_ENTRY, | |
59 | CN_FS_DEVRW, | |
60 | CN_MEM_SWAPOUT, | |
61 | CN_TIMERADD, | |
62 | CN_SCSI_DISPATCH_CMD, | |
63 | CN_IDE_CORE_CP, | |
64 | CN_DIRECT, | |
8bb31b9d AG |
65 | }; |
66 | ||
67 | enum ctype { | |
93e2f585 NK |
68 | CT_NONE, |
69 | CT_PANIC, | |
70 | CT_BUG, | |
71 | CT_EXCEPTION, | |
72 | CT_LOOP, | |
73 | CT_OVERFLOW, | |
74 | CT_CORRUPT_STACK, | |
75 | CT_UNALIGNED_LOAD_STORE_WRITE, | |
76 | CT_OVERWRITE_ALLOCATION, | |
77 | CT_WRITE_AFTER_FREE, | |
78 | CT_SOFTLOCKUP, | |
79 | CT_HARDLOCKUP, | |
80 | CT_HUNG_TASK, | |
8bb31b9d AG |
81 | }; |
82 | ||
83 | static char* cp_name[] = { | |
84 | "INT_HARDWARE_ENTRY", | |
85 | "INT_HW_IRQ_EN", | |
86 | "INT_TASKLET_ENTRY", | |
87 | "FS_DEVRW", | |
88 | "MEM_SWAPOUT", | |
89 | "TIMERADD", | |
90 | "SCSI_DISPATCH_CMD", | |
0347af4e SK |
91 | "IDE_CORE_CP", |
92 | "DIRECT", | |
8bb31b9d AG |
93 | }; |
94 | ||
95 | static char* cp_type[] = { | |
96 | "PANIC", | |
97 | "BUG", | |
98 | "EXCEPTION", | |
99 | "LOOP", | |
0347af4e SK |
100 | "OVERFLOW", |
101 | "CORRUPT_STACK", | |
102 | "UNALIGNED_LOAD_STORE_WRITE", | |
103 | "OVERWRITE_ALLOCATION", | |
104 | "WRITE_AFTER_FREE", | |
a48223f9 FW |
105 | "SOFTLOCKUP", |
106 | "HARDLOCKUP", | |
107 | "HUNG_TASK", | |
8bb31b9d AG |
108 | }; |
109 | ||
110 | static struct jprobe lkdtm; | |
111 | ||
112 | static int lkdtm_parse_commandline(void); | |
113 | static void lkdtm_handler(void); | |
114 | ||
ec1c620b AV |
115 | static char* cpoint_name; |
116 | static char* cpoint_type; | |
8bb31b9d AG |
117 | static int cpoint_count = DEFAULT_COUNT; |
118 | static int recur_count = REC_NUM_DEFAULT; | |
119 | ||
93e2f585 NK |
120 | static enum cname cpoint = CN_INVALID; |
121 | static enum ctype cptype = CT_NONE; | |
8bb31b9d | 122 | static int count = DEFAULT_COUNT; |
aa2c96d6 | 123 | static DEFINE_SPINLOCK(count_lock); |
8bb31b9d AG |
124 | |
125 | module_param(recur_count, int, 0644); | |
5d861d92 RD |
126 | MODULE_PARM_DESC(recur_count, " Recursion level for the stack overflow test, "\ |
127 | "default is 10"); | |
dca41306 | 128 | module_param(cpoint_name, charp, 0444); |
5d861d92 | 129 | MODULE_PARM_DESC(cpoint_name, " Crash Point, where kernel is to be crashed"); |
dca41306 | 130 | module_param(cpoint_type, charp, 0444); |
5d861d92 RD |
131 | MODULE_PARM_DESC(cpoint_type, " Crash Point Type, action to be taken on "\ |
132 | "hitting the crash point"); | |
133 | module_param(cpoint_count, int, 0644); | |
134 | MODULE_PARM_DESC(cpoint_count, " Crash Point Count, number of times the "\ | |
135 | "crash point is to be hit to trigger action"); | |
8bb31b9d | 136 | |
2118116e | 137 | static unsigned int jp_do_irq(unsigned int irq) |
8bb31b9d AG |
138 | { |
139 | lkdtm_handler(); | |
140 | jprobe_return(); | |
141 | return 0; | |
142 | } | |
143 | ||
2118116e AB |
144 | static irqreturn_t jp_handle_irq_event(unsigned int irq, |
145 | struct irqaction *action) | |
8bb31b9d AG |
146 | { |
147 | lkdtm_handler(); | |
148 | jprobe_return(); | |
149 | return 0; | |
150 | } | |
151 | ||
2118116e | 152 | static void jp_tasklet_action(struct softirq_action *a) |
8bb31b9d AG |
153 | { |
154 | lkdtm_handler(); | |
155 | jprobe_return(); | |
156 | } | |
157 | ||
2118116e | 158 | static void jp_ll_rw_block(int rw, int nr, struct buffer_head *bhs[]) |
8bb31b9d AG |
159 | { |
160 | lkdtm_handler(); | |
161 | jprobe_return(); | |
162 | } | |
163 | ||
164 | struct scan_control; | |
165 | ||
2118116e AB |
166 | static unsigned long jp_shrink_inactive_list(unsigned long max_scan, |
167 | struct zone *zone, | |
168 | struct scan_control *sc) | |
8bb31b9d AG |
169 | { |
170 | lkdtm_handler(); | |
171 | jprobe_return(); | |
172 | return 0; | |
173 | } | |
174 | ||
2118116e AB |
175 | static int jp_hrtimer_start(struct hrtimer *timer, ktime_t tim, |
176 | const enum hrtimer_mode mode) | |
8bb31b9d AG |
177 | { |
178 | lkdtm_handler(); | |
179 | jprobe_return(); | |
180 | return 0; | |
181 | } | |
182 | ||
2118116e | 183 | static int jp_scsi_dispatch_cmd(struct scsi_cmnd *cmd) |
8bb31b9d AG |
184 | { |
185 | lkdtm_handler(); | |
186 | jprobe_return(); | |
187 | return 0; | |
188 | } | |
189 | ||
190 | #ifdef CONFIG_IDE | |
191 | int jp_generic_ide_ioctl(ide_drive_t *drive, struct file *file, | |
192 | struct block_device *bdev, unsigned int cmd, | |
193 | unsigned long arg) | |
194 | { | |
195 | lkdtm_handler(); | |
196 | jprobe_return(); | |
197 | return 0; | |
198 | } | |
199 | #endif | |
200 | ||
0347af4e SK |
201 | /* Return the crashpoint number or NONE if the name is invalid */ |
202 | static enum ctype parse_cp_type(const char *what, size_t count) | |
203 | { | |
204 | int i; | |
205 | ||
206 | for (i = 0; i < ARRAY_SIZE(cp_type); i++) { | |
207 | if (!strcmp(what, cp_type[i])) | |
208 | return i + 1; | |
209 | } | |
210 | ||
93e2f585 | 211 | return CT_NONE; |
0347af4e SK |
212 | } |
213 | ||
214 | static const char *cp_type_to_str(enum ctype type) | |
215 | { | |
93e2f585 | 216 | if (type == CT_NONE || type < 0 || type > ARRAY_SIZE(cp_type)) |
0347af4e SK |
217 | return "None"; |
218 | ||
219 | return cp_type[type - 1]; | |
220 | } | |
221 | ||
222 | static const char *cp_name_to_str(enum cname name) | |
223 | { | |
93e2f585 | 224 | if (name == CN_INVALID || name < 0 || name > ARRAY_SIZE(cp_name)) |
0347af4e SK |
225 | return "INVALID"; |
226 | ||
227 | return cp_name[name - 1]; | |
228 | } | |
229 | ||
230 | ||
8bb31b9d AG |
231 | static int lkdtm_parse_commandline(void) |
232 | { | |
233 | int i; | |
aa2c96d6 | 234 | unsigned long flags; |
8bb31b9d | 235 | |
0347af4e | 236 | if (cpoint_count < 1 || recur_count < 1) |
8bb31b9d AG |
237 | return -EINVAL; |
238 | ||
aa2c96d6 | 239 | spin_lock_irqsave(&count_lock, flags); |
0347af4e | 240 | count = cpoint_count; |
aa2c96d6 | 241 | spin_unlock_irqrestore(&count_lock, flags); |
0347af4e SK |
242 | |
243 | /* No special parameters */ | |
244 | if (!cpoint_type && !cpoint_name) | |
245 | return 0; | |
246 | ||
247 | /* Neither or both of these need to be set */ | |
248 | if (!cpoint_type || !cpoint_name) | |
249 | return -EINVAL; | |
250 | ||
251 | cptype = parse_cp_type(cpoint_type, strlen(cpoint_type)); | |
93e2f585 | 252 | if (cptype == CT_NONE) |
0347af4e SK |
253 | return -EINVAL; |
254 | ||
255 | for (i = 0; i < ARRAY_SIZE(cp_name); i++) { | |
8bb31b9d AG |
256 | if (!strcmp(cpoint_name, cp_name[i])) { |
257 | cpoint = i + 1; | |
0347af4e | 258 | return 0; |
8bb31b9d AG |
259 | } |
260 | } | |
261 | ||
0347af4e SK |
262 | /* Could not find a valid crash point */ |
263 | return -EINVAL; | |
8bb31b9d AG |
264 | } |
265 | ||
266 | static int recursive_loop(int a) | |
267 | { | |
268 | char buf[1024]; | |
269 | ||
270 | memset(buf,0xFF,1024); | |
271 | recur_count--; | |
272 | if (!recur_count) | |
273 | return 0; | |
274 | else | |
275 | return recursive_loop(a); | |
276 | } | |
277 | ||
0347af4e | 278 | static void lkdtm_do_action(enum ctype which) |
8bb31b9d | 279 | { |
0347af4e | 280 | switch (which) { |
93e2f585 | 281 | case CT_PANIC: |
0347af4e SK |
282 | panic("dumptest"); |
283 | break; | |
93e2f585 | 284 | case CT_BUG: |
0347af4e SK |
285 | BUG(); |
286 | break; | |
93e2f585 | 287 | case CT_EXCEPTION: |
0347af4e SK |
288 | *((int *) 0) = 0; |
289 | break; | |
93e2f585 | 290 | case CT_LOOP: |
0347af4e SK |
291 | for (;;) |
292 | ; | |
293 | break; | |
93e2f585 | 294 | case CT_OVERFLOW: |
0347af4e SK |
295 | (void) recursive_loop(0); |
296 | break; | |
93e2f585 | 297 | case CT_CORRUPT_STACK: { |
0347af4e SK |
298 | volatile u32 data[8]; |
299 | volatile u32 *p = data; | |
300 | ||
301 | p[12] = 0x12345678; | |
302 | break; | |
303 | } | |
93e2f585 | 304 | case CT_UNALIGNED_LOAD_STORE_WRITE: { |
0347af4e SK |
305 | static u8 data[5] __attribute__((aligned(4))) = {1, 2, |
306 | 3, 4, 5}; | |
307 | u32 *p; | |
308 | u32 val = 0x12345678; | |
309 | ||
310 | p = (u32 *)(data + 1); | |
311 | if (*p == 0) | |
312 | val = 0x87654321; | |
313 | *p = val; | |
314 | break; | |
315 | } | |
93e2f585 | 316 | case CT_OVERWRITE_ALLOCATION: { |
0347af4e SK |
317 | size_t len = 1020; |
318 | u32 *data = kmalloc(len, GFP_KERNEL); | |
319 | ||
320 | data[1024 / sizeof(u32)] = 0x12345678; | |
321 | kfree(data); | |
322 | break; | |
323 | } | |
93e2f585 | 324 | case CT_WRITE_AFTER_FREE: { |
0347af4e SK |
325 | size_t len = 1024; |
326 | u32 *data = kmalloc(len, GFP_KERNEL); | |
327 | ||
328 | kfree(data); | |
329 | schedule(); | |
330 | memset(data, 0x78, len); | |
331 | break; | |
332 | } | |
93e2f585 | 333 | case CT_SOFTLOCKUP: |
a48223f9 FW |
334 | preempt_disable(); |
335 | for (;;) | |
336 | cpu_relax(); | |
337 | break; | |
93e2f585 | 338 | case CT_HARDLOCKUP: |
a48223f9 FW |
339 | local_irq_disable(); |
340 | for (;;) | |
341 | cpu_relax(); | |
342 | break; | |
93e2f585 | 343 | case CT_HUNG_TASK: |
a48223f9 FW |
344 | set_current_state(TASK_UNINTERRUPTIBLE); |
345 | schedule(); | |
346 | break; | |
93e2f585 | 347 | case CT_NONE: |
0347af4e SK |
348 | default: |
349 | break; | |
350 | } | |
351 | ||
352 | } | |
353 | ||
354 | static void lkdtm_handler(void) | |
355 | { | |
aa2c96d6 | 356 | unsigned long flags; |
92618184 | 357 | bool do_it = false; |
aa2c96d6 JH |
358 | |
359 | spin_lock_irqsave(&count_lock, flags); | |
0347af4e SK |
360 | count--; |
361 | printk(KERN_INFO "lkdtm: Crash point %s of type %s hit, trigger in %d rounds\n", | |
362 | cp_name_to_str(cpoint), cp_type_to_str(cptype), count); | |
8bb31b9d AG |
363 | |
364 | if (count == 0) { | |
92618184 | 365 | do_it = true; |
8bb31b9d AG |
366 | count = cpoint_count; |
367 | } | |
aa2c96d6 | 368 | spin_unlock_irqrestore(&count_lock, flags); |
92618184 CW |
369 | |
370 | if (do_it) | |
371 | lkdtm_do_action(cptype); | |
8bb31b9d AG |
372 | } |
373 | ||
0347af4e | 374 | static int lkdtm_register_cpoint(enum cname which) |
8bb31b9d AG |
375 | { |
376 | int ret; | |
377 | ||
93e2f585 | 378 | cpoint = CN_INVALID; |
0347af4e SK |
379 | if (lkdtm.entry != NULL) |
380 | unregister_jprobe(&lkdtm); | |
8bb31b9d | 381 | |
0347af4e | 382 | switch (which) { |
93e2f585 | 383 | case CN_DIRECT: |
0347af4e SK |
384 | lkdtm_do_action(cptype); |
385 | return 0; | |
93e2f585 | 386 | case CN_INT_HARDWARE_ENTRY: |
f58f2fa9 | 387 | lkdtm.kp.symbol_name = "do_IRQ"; |
8bb31b9d AG |
388 | lkdtm.entry = (kprobe_opcode_t*) jp_do_irq; |
389 | break; | |
93e2f585 | 390 | case CN_INT_HW_IRQ_EN: |
8bb31b9d AG |
391 | lkdtm.kp.symbol_name = "handle_IRQ_event"; |
392 | lkdtm.entry = (kprobe_opcode_t*) jp_handle_irq_event; | |
393 | break; | |
93e2f585 | 394 | case CN_INT_TASKLET_ENTRY: |
8bb31b9d AG |
395 | lkdtm.kp.symbol_name = "tasklet_action"; |
396 | lkdtm.entry = (kprobe_opcode_t*) jp_tasklet_action; | |
397 | break; | |
93e2f585 | 398 | case CN_FS_DEVRW: |
8bb31b9d AG |
399 | lkdtm.kp.symbol_name = "ll_rw_block"; |
400 | lkdtm.entry = (kprobe_opcode_t*) jp_ll_rw_block; | |
401 | break; | |
93e2f585 | 402 | case CN_MEM_SWAPOUT: |
18a61e4a AG |
403 | lkdtm.kp.symbol_name = "shrink_inactive_list"; |
404 | lkdtm.entry = (kprobe_opcode_t*) jp_shrink_inactive_list; | |
8bb31b9d | 405 | break; |
93e2f585 | 406 | case CN_TIMERADD: |
8bb31b9d AG |
407 | lkdtm.kp.symbol_name = "hrtimer_start"; |
408 | lkdtm.entry = (kprobe_opcode_t*) jp_hrtimer_start; | |
409 | break; | |
93e2f585 | 410 | case CN_SCSI_DISPATCH_CMD: |
8bb31b9d AG |
411 | lkdtm.kp.symbol_name = "scsi_dispatch_cmd"; |
412 | lkdtm.entry = (kprobe_opcode_t*) jp_scsi_dispatch_cmd; | |
413 | break; | |
93e2f585 | 414 | case CN_IDE_CORE_CP: |
8bb31b9d AG |
415 | #ifdef CONFIG_IDE |
416 | lkdtm.kp.symbol_name = "generic_ide_ioctl"; | |
417 | lkdtm.entry = (kprobe_opcode_t*) jp_generic_ide_ioctl; | |
418 | #else | |
0347af4e SK |
419 | printk(KERN_INFO "lkdtm: Crash point not available\n"); |
420 | return -EINVAL; | |
8bb31b9d AG |
421 | #endif |
422 | break; | |
423 | default: | |
0347af4e SK |
424 | printk(KERN_INFO "lkdtm: Invalid Crash Point\n"); |
425 | return -EINVAL; | |
8bb31b9d AG |
426 | } |
427 | ||
0347af4e | 428 | cpoint = which; |
8bb31b9d | 429 | if ((ret = register_jprobe(&lkdtm)) < 0) { |
0347af4e | 430 | printk(KERN_INFO "lkdtm: Couldn't register jprobe\n"); |
93e2f585 | 431 | cpoint = CN_INVALID; |
0347af4e SK |
432 | } |
433 | ||
434 | return ret; | |
435 | } | |
436 | ||
437 | static ssize_t do_register_entry(enum cname which, struct file *f, | |
438 | const char __user *user_buf, size_t count, loff_t *off) | |
439 | { | |
440 | char *buf; | |
441 | int err; | |
442 | ||
443 | if (count >= PAGE_SIZE) | |
444 | return -EINVAL; | |
445 | ||
446 | buf = (char *)__get_free_page(GFP_KERNEL); | |
447 | if (!buf) | |
448 | return -ENOMEM; | |
449 | if (copy_from_user(buf, user_buf, count)) { | |
450 | free_page((unsigned long) buf); | |
451 | return -EFAULT; | |
452 | } | |
453 | /* NULL-terminate and remove enter */ | |
454 | buf[count] = '\0'; | |
455 | strim(buf); | |
456 | ||
457 | cptype = parse_cp_type(buf, count); | |
458 | free_page((unsigned long) buf); | |
459 | ||
93e2f585 | 460 | if (cptype == CT_NONE) |
0347af4e SK |
461 | return -EINVAL; |
462 | ||
463 | err = lkdtm_register_cpoint(which); | |
464 | if (err < 0) | |
465 | return err; | |
466 | ||
467 | *off += count; | |
468 | ||
469 | return count; | |
470 | } | |
471 | ||
472 | /* Generic read callback that just prints out the available crash types */ | |
473 | static ssize_t lkdtm_debugfs_read(struct file *f, char __user *user_buf, | |
474 | size_t count, loff_t *off) | |
475 | { | |
476 | char *buf; | |
477 | int i, n, out; | |
478 | ||
479 | buf = (char *)__get_free_page(GFP_KERNEL); | |
086ff4b3 AC |
480 | if (buf == NULL) |
481 | return -ENOMEM; | |
0347af4e SK |
482 | |
483 | n = snprintf(buf, PAGE_SIZE, "Available crash types:\n"); | |
484 | for (i = 0; i < ARRAY_SIZE(cp_type); i++) | |
485 | n += snprintf(buf + n, PAGE_SIZE - n, "%s\n", cp_type[i]); | |
486 | buf[n] = '\0'; | |
487 | ||
488 | out = simple_read_from_buffer(user_buf, count, off, | |
489 | buf, n); | |
490 | free_page((unsigned long) buf); | |
491 | ||
492 | return out; | |
493 | } | |
494 | ||
495 | static int lkdtm_debugfs_open(struct inode *inode, struct file *file) | |
496 | { | |
497 | return 0; | |
498 | } | |
499 | ||
500 | ||
501 | static ssize_t int_hardware_entry(struct file *f, const char __user *buf, | |
502 | size_t count, loff_t *off) | |
503 | { | |
93e2f585 | 504 | return do_register_entry(CN_INT_HARDWARE_ENTRY, f, buf, count, off); |
0347af4e SK |
505 | } |
506 | ||
507 | static ssize_t int_hw_irq_en(struct file *f, const char __user *buf, | |
508 | size_t count, loff_t *off) | |
509 | { | |
93e2f585 | 510 | return do_register_entry(CN_INT_HW_IRQ_EN, f, buf, count, off); |
0347af4e SK |
511 | } |
512 | ||
513 | static ssize_t int_tasklet_entry(struct file *f, const char __user *buf, | |
514 | size_t count, loff_t *off) | |
515 | { | |
93e2f585 | 516 | return do_register_entry(CN_INT_TASKLET_ENTRY, f, buf, count, off); |
0347af4e SK |
517 | } |
518 | ||
519 | static ssize_t fs_devrw_entry(struct file *f, const char __user *buf, | |
520 | size_t count, loff_t *off) | |
521 | { | |
93e2f585 | 522 | return do_register_entry(CN_FS_DEVRW, f, buf, count, off); |
0347af4e SK |
523 | } |
524 | ||
525 | static ssize_t mem_swapout_entry(struct file *f, const char __user *buf, | |
526 | size_t count, loff_t *off) | |
527 | { | |
93e2f585 | 528 | return do_register_entry(CN_MEM_SWAPOUT, f, buf, count, off); |
0347af4e SK |
529 | } |
530 | ||
531 | static ssize_t timeradd_entry(struct file *f, const char __user *buf, | |
532 | size_t count, loff_t *off) | |
533 | { | |
93e2f585 | 534 | return do_register_entry(CN_TIMERADD, f, buf, count, off); |
0347af4e SK |
535 | } |
536 | ||
537 | static ssize_t scsi_dispatch_cmd_entry(struct file *f, | |
538 | const char __user *buf, size_t count, loff_t *off) | |
539 | { | |
93e2f585 | 540 | return do_register_entry(CN_SCSI_DISPATCH_CMD, f, buf, count, off); |
0347af4e SK |
541 | } |
542 | ||
543 | static ssize_t ide_core_cp_entry(struct file *f, const char __user *buf, | |
544 | size_t count, loff_t *off) | |
545 | { | |
93e2f585 | 546 | return do_register_entry(CN_IDE_CORE_CP, f, buf, count, off); |
0347af4e SK |
547 | } |
548 | ||
549 | /* Special entry to just crash directly. Available without KPROBEs */ | |
550 | static ssize_t direct_entry(struct file *f, const char __user *user_buf, | |
551 | size_t count, loff_t *off) | |
552 | { | |
553 | enum ctype type; | |
554 | char *buf; | |
555 | ||
556 | if (count >= PAGE_SIZE) | |
557 | return -EINVAL; | |
558 | if (count < 1) | |
559 | return -EINVAL; | |
560 | ||
561 | buf = (char *)__get_free_page(GFP_KERNEL); | |
562 | if (!buf) | |
563 | return -ENOMEM; | |
564 | if (copy_from_user(buf, user_buf, count)) { | |
565 | free_page((unsigned long) buf); | |
566 | return -EFAULT; | |
567 | } | |
568 | /* NULL-terminate and remove enter */ | |
569 | buf[count] = '\0'; | |
570 | strim(buf); | |
571 | ||
572 | type = parse_cp_type(buf, count); | |
573 | free_page((unsigned long) buf); | |
93e2f585 | 574 | if (type == CT_NONE) |
0347af4e SK |
575 | return -EINVAL; |
576 | ||
577 | printk(KERN_INFO "lkdtm: Performing direct entry %s\n", | |
578 | cp_type_to_str(type)); | |
579 | lkdtm_do_action(type); | |
580 | *off += count; | |
581 | ||
582 | return count; | |
583 | } | |
584 | ||
585 | struct crash_entry { | |
586 | const char *name; | |
587 | const struct file_operations fops; | |
588 | }; | |
589 | ||
590 | static const struct crash_entry crash_entries[] = { | |
591 | {"DIRECT", {.read = lkdtm_debugfs_read, | |
05271ec4 | 592 | .llseek = generic_file_llseek, |
0347af4e SK |
593 | .open = lkdtm_debugfs_open, |
594 | .write = direct_entry} }, | |
595 | {"INT_HARDWARE_ENTRY", {.read = lkdtm_debugfs_read, | |
05271ec4 | 596 | .llseek = generic_file_llseek, |
0347af4e SK |
597 | .open = lkdtm_debugfs_open, |
598 | .write = int_hardware_entry} }, | |
599 | {"INT_HW_IRQ_EN", {.read = lkdtm_debugfs_read, | |
05271ec4 | 600 | .llseek = generic_file_llseek, |
0347af4e SK |
601 | .open = lkdtm_debugfs_open, |
602 | .write = int_hw_irq_en} }, | |
603 | {"INT_TASKLET_ENTRY", {.read = lkdtm_debugfs_read, | |
05271ec4 | 604 | .llseek = generic_file_llseek, |
0347af4e SK |
605 | .open = lkdtm_debugfs_open, |
606 | .write = int_tasklet_entry} }, | |
607 | {"FS_DEVRW", {.read = lkdtm_debugfs_read, | |
05271ec4 | 608 | .llseek = generic_file_llseek, |
0347af4e SK |
609 | .open = lkdtm_debugfs_open, |
610 | .write = fs_devrw_entry} }, | |
611 | {"MEM_SWAPOUT", {.read = lkdtm_debugfs_read, | |
05271ec4 | 612 | .llseek = generic_file_llseek, |
0347af4e SK |
613 | .open = lkdtm_debugfs_open, |
614 | .write = mem_swapout_entry} }, | |
615 | {"TIMERADD", {.read = lkdtm_debugfs_read, | |
05271ec4 | 616 | .llseek = generic_file_llseek, |
0347af4e SK |
617 | .open = lkdtm_debugfs_open, |
618 | .write = timeradd_entry} }, | |
619 | {"SCSI_DISPATCH_CMD", {.read = lkdtm_debugfs_read, | |
05271ec4 | 620 | .llseek = generic_file_llseek, |
0347af4e SK |
621 | .open = lkdtm_debugfs_open, |
622 | .write = scsi_dispatch_cmd_entry} }, | |
623 | {"IDE_CORE_CP", {.read = lkdtm_debugfs_read, | |
05271ec4 | 624 | .llseek = generic_file_llseek, |
0347af4e SK |
625 | .open = lkdtm_debugfs_open, |
626 | .write = ide_core_cp_entry} }, | |
627 | }; | |
628 | ||
629 | static struct dentry *lkdtm_debugfs_root; | |
630 | ||
631 | static int __init lkdtm_module_init(void) | |
632 | { | |
633 | int ret = -EINVAL; | |
634 | int n_debugfs_entries = 1; /* Assume only the direct entry */ | |
635 | int i; | |
636 | ||
637 | /* Register debugfs interface */ | |
638 | lkdtm_debugfs_root = debugfs_create_dir("provoke-crash", NULL); | |
639 | if (!lkdtm_debugfs_root) { | |
640 | printk(KERN_ERR "lkdtm: creating root dir failed\n"); | |
641 | return -ENODEV; | |
642 | } | |
643 | ||
644 | #ifdef CONFIG_KPROBES | |
645 | n_debugfs_entries = ARRAY_SIZE(crash_entries); | |
646 | #endif | |
647 | ||
648 | for (i = 0; i < n_debugfs_entries; i++) { | |
649 | const struct crash_entry *cur = &crash_entries[i]; | |
650 | struct dentry *de; | |
651 | ||
652 | de = debugfs_create_file(cur->name, 0644, lkdtm_debugfs_root, | |
653 | NULL, &cur->fops); | |
654 | if (de == NULL) { | |
655 | printk(KERN_ERR "lkdtm: could not create %s\n", | |
656 | cur->name); | |
657 | goto out_err; | |
658 | } | |
659 | } | |
660 | ||
661 | if (lkdtm_parse_commandline() == -EINVAL) { | |
662 | printk(KERN_INFO "lkdtm: Invalid command\n"); | |
663 | goto out_err; | |
664 | } | |
665 | ||
93e2f585 | 666 | if (cpoint != CN_INVALID && cptype != CT_NONE) { |
0347af4e SK |
667 | ret = lkdtm_register_cpoint(cpoint); |
668 | if (ret < 0) { | |
669 | printk(KERN_INFO "lkdtm: Invalid crash point %d\n", | |
670 | cpoint); | |
671 | goto out_err; | |
672 | } | |
673 | printk(KERN_INFO "lkdtm: Crash point %s of type %s registered\n", | |
674 | cpoint_name, cpoint_type); | |
675 | } else { | |
676 | printk(KERN_INFO "lkdtm: No crash points registered, enable through debugfs\n"); | |
8bb31b9d AG |
677 | } |
678 | ||
8bb31b9d | 679 | return 0; |
0347af4e SK |
680 | |
681 | out_err: | |
682 | debugfs_remove_recursive(lkdtm_debugfs_root); | |
683 | return ret; | |
8bb31b9d AG |
684 | } |
685 | ||
2118116e | 686 | static void __exit lkdtm_module_exit(void) |
8bb31b9d | 687 | { |
0347af4e SK |
688 | debugfs_remove_recursive(lkdtm_debugfs_root); |
689 | ||
690 | unregister_jprobe(&lkdtm); | |
691 | printk(KERN_INFO "lkdtm: Crash point unregistered\n"); | |
8bb31b9d AG |
692 | } |
693 | ||
694 | module_init(lkdtm_module_init); | |
695 | module_exit(lkdtm_module_exit); | |
696 | ||
697 | MODULE_LICENSE("GPL"); |