1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
|
/*
* Linux Kernel Dump Test Module for testing kernel crashes conditions:
* induces system failures at predefined crashpoints and under predefined
* operational conditions in order to evaluate the reliability of kernel
* sanity checking and crash dumps obtained using different dumping
* solutions.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* Copyright (C) IBM Corporation, 2006
*
* Author: Ankita Garg <ankita@in.ibm.com>
*
* It is adapted from the Linux Kernel Dump Test Tool by
* Fernando Luis Vazquez Cao <http://lkdtt.sourceforge.net>
*
* Debugfs support added by Simon Kagstrom <simon.kagstrom@netinsight.net>
*
* See Documentation/fault-injection/provoke-crashes.txt for instructions
*/
#include "lkdtm.h"
#include <linux/fs.h>
#include <linux/module.h>
#include <linux/buffer_head.h>
#include <linux/kprobes.h>
#include <linux/list.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/hrtimer.h>
#include <linux/slab.h>
#include <scsi/scsi_cmnd.h>
#include <linux/debugfs.h>
#ifdef CONFIG_IDE
#include <linux/ide.h>
#endif
#define DEFAULT_COUNT 10
static int lkdtm_debugfs_open(struct inode *inode, struct file *file);
static ssize_t lkdtm_debugfs_read(struct file *f, char __user *user_buf,
size_t count, loff_t *off);
static ssize_t direct_entry(struct file *f, const char __user *user_buf,
size_t count, loff_t *off);
#ifdef CONFIG_KPROBES
static int lkdtm_kprobe_handler(struct kprobe *kp, struct pt_regs *regs);
static ssize_t lkdtm_debugfs_entry(struct file *f,
const char __user *user_buf,
size_t count, loff_t *off);
# define CRASHPOINT_KPROBE(_symbol) \
.kprobe = { \
.symbol_name = (_symbol), \
.pre_handler = lkdtm_kprobe_handler, \
},
# define CRASHPOINT_WRITE(_symbol) \
(_symbol) ? lkdtm_debugfs_entry : direct_entry
#else
# define CRASHPOINT_KPROBE(_symbol)
# define CRASHPOINT_WRITE(_symbol) direct_entry
#endif
/* Crash points */
struct crashpoint {
const char *name;
const struct file_operations fops;
struct kprobe kprobe;
};
#define CRASHPOINT(_name, _symbol) \
{ \
.name = _name, \
.fops = { \
.read = lkdtm_debugfs_read, \
.llseek = generic_file_llseek, \
.open = lkdtm_debugfs_open, \
.write = CRASHPOINT_WRITE(_symbol) \
}, \
CRASHPOINT_KPROBE(_symbol) \
}
/* Define the possible places where we can trigger a crash point. */
static struct crashpoint crashpoints[] = {
CRASHPOINT("DIRECT", NULL),
#ifdef CONFIG_KPROBES
CRASHPOINT("INT_HARDWARE_ENTRY", "do_IRQ"),
CRASHPOINT("INT_HW_IRQ_EN", "handle_IRQ_event"),
CRASHPOINT("INT_TASKLET_ENTRY", "tasklet_action"),
CRASHPOINT("FS_DEVRW", "ll_rw_block"),
CRASHPOINT("MEM_SWAPOUT", "shrink_inactive_list"),
CRASHPOINT("TIMERADD", "hrtimer_start"),
CRASHPOINT("SCSI_DISPATCH_CMD", "scsi_dispatch_cmd"),
# ifdef CONFIG_IDE
CRASHPOINT("IDE_CORE_CP", "generic_ide_ioctl"),
# endif
#endif
};
/* Crash types. */
struct crashtype {
const char *name;
void (*func)(void);
};
#define CRASHTYPE(_name) \
{ \
.name = __stringify(_name), \
.func = lkdtm_ ## _name, \
}
/* Define the possible types of crashes that can be triggered. */
static const struct crashtype crashtypes[] = {
CRASHTYPE(PANIC),
CRASHTYPE(BUG),
CRASHTYPE(WARNING),
CRASHTYPE(EXCEPTION),
CRASHTYPE(LOOP),
CRASHTYPE(OVERFLOW),
CRASHTYPE(CORRUPT_LIST_ADD),
CRASHTYPE(CORRUPT_LIST_DEL),
CRASHTYPE(CORRUPT_USER_DS),
CRASHTYPE(CORRUPT_STACK),
CRASHTYPE(CORRUPT_STACK_STRONG),
CRASHTYPE(STACK_GUARD_PAGE_LEADING),
CRASHTYPE(STACK_GUARD_PAGE_TRAILING),
CRASHTYPE(UNALIGNED_LOAD_STORE_WRITE),
CRASHTYPE(OVERWRITE_ALLOCATION),
CRASHTYPE(WRITE_AFTER_FREE),
CRASHTYPE(READ_AFTER_FREE),
CRASHTYPE(WRITE_BUDDY_AFTER_FREE),
CRASHTYPE(READ_BUDDY_AFTER_FREE),
CRASHTYPE(SOFTLOCKUP),
CRASHTYPE(HARDLOCKUP),
CRASHTYPE(SPINLOCKUP),
CRASHTYPE(HUNG_TASK),
CRASHTYPE(EXEC_DATA),
CRASHTYPE(EXEC_STACK),
CRASHTYPE(EXEC_KMALLOC),
CRASHTYPE(EXEC_VMALLOC),
CRASHTYPE(EXEC_RODATA),
CRASHTYPE(EXEC_USERSPACE),
CRASHTYPE(ACCESS_USERSPACE),
CRASHTYPE(WRITE_RO),
CRASHTYPE(WRITE_RO_AFTER_INIT),
CRASHTYPE(WRITE_KERN),
CRASHTYPE(REFCOUNT_INC_OVERFLOW),
CRASHTYPE(REFCOUNT_ADD_OVERFLOW),
CRASHTYPE(REFCOUNT_INC_NOT_ZERO_OVERFLOW),
CRASHTYPE(REFCOUNT_ADD_NOT_ZERO_OVERFLOW),
CRASHTYPE(REFCOUNT_DEC_ZERO),
CRASHTYPE(REFCOUNT_DEC_NEGATIVE),
CRASHTYPE(REFCOUNT_DEC_AND_TEST_NEGATIVE),
CRASHTYPE(REFCOUNT_SUB_AND_TEST_NEGATIVE),
CRASHTYPE(REFCOUNT_INC_ZERO),
CRASHTYPE(REFCOUNT_ADD_ZERO),
CRASHTYPE(REFCOUNT_INC_SATURATED),
CRASHTYPE(REFCOUNT_DEC_SATURATED),
CRASHTYPE(REFCOUNT_ADD_SATURATED),
CRASHTYPE(REFCOUNT_INC_NOT_ZERO_SATURATED),
CRASHTYPE(REFCOUNT_ADD_NOT_ZERO_SATURATED),
CRASHTYPE(REFCOUNT_DEC_AND_TEST_SATURATED),
CRASHTYPE(REFCOUNT_SUB_AND_TEST_SATURATED),
CRASHTYPE(REFCOUNT_TIMING),
CRASHTYPE(ATOMIC_TIMING),
CRASHTYPE(USERCOPY_HEAP_SIZE_TO),
CRASHTYPE(USERCOPY_HEAP_SIZE_FROM),
CRASHTYPE(USERCOPY_HEAP_FLAG_TO),
CRASHTYPE(USERCOPY_HEAP_FLAG_FROM),
CRASHTYPE(USERCOPY_STACK_FRAME_TO),
CRASHTYPE(USERCOPY_STACK_FRAME_FROM),
CRASHTYPE(USERCOPY_STACK_BEYOND),
CRASHTYPE(USERCOPY_KERNEL),
};
/* Global kprobe entry and crashtype. */
static struct kprobe *lkdtm_kprobe;
static struct crashpoint *lkdtm_crashpoint;
static const struct crashtype *lkdtm_crashtype;
/* Module parameters */
static int recur_count = -1;
module_param(recur_count, int, 0644);
MODULE_PARM_DESC(recur_count, " Recursion level for the stack overflow test");
static char* cpoint_name;
module_param(cpoint_name, charp, 0444);
MODULE_PARM_DESC(cpoint_name, " Crash Point, where kernel is to be crashed");
static char* cpoint_type;
module_param(cpoint_type, charp, 0444);
MODULE_PARM_DESC(cpoint_type, " Crash Point Type, action to be taken on "\
"hitting the crash point");
static int cpoint_count = DEFAULT_COUNT;
module_param(cpoint_count, int, 0644);
MODULE_PARM_DESC(cpoint_count, " Crash Point Count, number of times the "\
"crash point is to be hit to trigger action");
/* Return the crashtype number or NULL if the name is invalid */
static const struct crashtype *find_crashtype(const char *name)
{
int i;
for (i = 0; i < ARRAY_SIZE(crashtypes); i++) {
if (!strcmp(name, crashtypes[i].name))
return &crashtypes[i];
}
return NULL;
}
/*
* This is forced noinline just so it distinctly shows up in the stackdump
* which makes validation of expected lkdtm crashes easier.
*/
static noinline void lkdtm_do_action(const struct crashtype *crashtype)
{
if (WARN_ON(!crashtype || !crashtype->func))
return;
crashtype->func();
}
static int lkdtm_register_cpoint(struct crashpoint *crashpoint,
const struct crashtype *crashtype)
{
int ret;
/* If this doesn't have a symbol, just call immediately. */
if (!crashpoint->kprobe.symbol_name) {
lkdtm_do_action(crashtype);
return 0;
}
if (lkdtm_kprobe != NULL)
unregister_kprobe(lkdtm_kprobe);
lkdtm_crashpoint = crashpoint;
lkdtm_crashtype = crashtype;
lkdtm_kprobe = &crashpoint->kprobe;
ret = register_kprobe(lkdtm_kprobe);
if (ret < 0) {
pr_info("Couldn't register kprobe %s\n",
crashpoint->kprobe.symbol_name);
lkdtm_kprobe = NULL;
lkdtm_crashpoint = NULL;
lkdtm_crashtype = NULL;
}
return ret;
}
#ifdef CONFIG_KPROBES
/* Global crash counter and spinlock. */
static int crash_count = DEFAULT_COUNT;
static DEFINE_SPINLOCK(crash_count_lock);
/* Called by kprobe entry points. */
static int lkdtm_kprobe_handler(struct kprobe *kp, struct pt_regs *regs)
{
unsigned long flags;
bool do_it = false;
if (WARN_ON(!lkdtm_crashpoint || !lkdtm_crashtype))
return 0;
spin_lock_irqsave(&crash_count_lock, flags);
crash_count--;
pr_info("Crash point %s of type %s hit, trigger in %d rounds\n",
lkdtm_crashpoint->name, lkdtm_crashtype->name, crash_count);
if (crash_count == 0) {
do_it = true;
crash_count = cpoint_count;
}
spin_unlock_irqrestore(&crash_count_lock, flags);
if (do_it)
lkdtm_do_action(lkdtm_crashtype);
return 0;
}
static ssize_t lkdtm_debugfs_entry(struct file *f,
const char __user *<
|