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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 *
29 * Debugfs support added by Simon Kagstrom <simon.kagstrom@netinsight.net>
30 *
31 * See Documentation/fault-injection/provoke-crashes.txt for instructions
32 */
33
34#include <linux/kernel.h>
35#include <linux/fs.h>
36#include <linux/module.h>
37#include <linux/buffer_head.h>
38#include <linux/kprobes.h>
39#include <linux/list.h>
40#include <linux/init.h>
41#include <linux/interrupt.h>
42#include <linux/hrtimer.h>
43#include <linux/slab.h>
44#include <scsi/scsi_cmnd.h>
45#include <linux/debugfs.h>
46
47#ifdef CONFIG_IDE
48#include <linux/ide.h>
49#endif
50
51#define DEFAULT_COUNT 10
52#define REC_NUM_DEFAULT 10
53
54enum cname {
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,
65};
66
67enum ctype {
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,
81};
82
83static 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",
91 "IDE_CORE_CP",
92 "DIRECT",
93};
94
95static char* cp_type[] = {
96 "PANIC",
97 "BUG",
98 "EXCEPTION",
99 "LOOP",
100 "OVERFLOW",
101 "CORRUPT_STACK",
102 "UNALIGNED_LOAD_STORE_WRITE",
103 "OVERWRITE_ALLOCATION",
104 "WRITE_AFTER_FREE",
105 "SOFTLOCKUP",
106 "HARDLOCKUP",
107 "HUNG_TASK",
108};
109
110static struct jprobe lkdtm;
111
112static int lkdtm_parse_commandline(void);
113static void lkdtm_handler(void);
114
115static char* cpoint_name;
116static char* cpoint_type;
117static int cpoint_count = DEFAULT_COUNT;
118static int recur_count = REC_NUM_DEFAULT;
119
120static enum cname cpoint = CN_INVALID;
121static enum ctype cptype = CT_NONE;
122static int count = DEFAULT_COUNT;
123static DEFINE_SPINLOCK(count_lock);
124
125module_param(recur_count, int, 0644);
126MODULE_PARM_DESC(recur_count, " Recursion level for the stack overflow test, "\
127 "default is 10");
128module_param(cpoint_name, charp, 0444);
129MODULE_PARM_DESC(cpoint_name, " Crash Point, where kernel is to be crashed");
130module_param(cpoint_type, charp, 0444);
131MODULE_PARM_DESC(cpoint_type, " Crash Point Type, action to be taken on "\
132 "hitting the crash point");
133module_param(cpoint_count, int, 0644);
134MODULE_PARM_DESC(cpoint_count, " Crash Point Count, number of times the "\
135 "crash point is to be hit to trigger action");
136
137static unsigned int jp_do_irq(unsigned int irq)
138{
139 lkdtm_handler();
140 jprobe_return();
141 return 0;
142}
143
144static irqreturn_t jp_handle_irq_event(unsigned int irq,
145 struct irqaction *action)
146{
147 lkdtm_handler();
148 jprobe_return();
149 return 0;
150}
151
152static void jp_tasklet_action(struct softirq_action *a)
153{
154 lkdtm_handler();
155 jprobe_return();
156}
157
158static void jp_ll_rw_block(int rw, int nr, struct buffer_head *bhs[])
159{
160 lkdtm_handler();
161 jprobe_return();
162}
163
164struct scan_control;
165
166static unsigned long jp_shrink_inactive_list(unsigned long max_scan,
167 struct zone *zone,
168 struct scan_control *sc)
169{
170 lkdtm_handler();
171 jprobe_return();
172 return 0;
173}
174
175static int jp_hrtimer_start(struct hrtimer *timer, ktime_t tim,
176 const enum hrtimer_mode mode)
177{
178 lkdtm_handler();
179 jprobe_return();
180 return 0;
181}
182
183static int jp_scsi_dispatch_cmd(struct scsi_cmnd *cmd)
184{
185 lkdtm_handler();
186 jprobe_return();
187 return 0;
188}
189
190#ifdef CONFIG_IDE
191int 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
201/* Return the crashpoint number or NONE if the name is invalid */
202static 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
211 return CT_NONE;
212}
213
214static const char *cp_type_to_str(enum ctype type)
215{
216 if (type == CT_NONE || type < 0 || type > ARRAY_SIZE(cp_type))
217 return "None";
218
219 return cp_type[type - 1];
220}
221
222static const char *cp_name_to_str(enum cname name)
223{
224 if (name == CN_INVALID || name < 0 || name > ARRAY_SIZE(cp_name))
225 return "INVALID";
226
227 return cp_name[name - 1];
228}
229
230
231static int lkdtm_parse_commandline(void)
232{
233 int i;
234 unsigned long flags;
235
236 if (cpoint_count < 1 || recur_count < 1)
237 return -EINVAL;
238
239 spin_lock_irqsave(&count_lock, flags);
240 count = cpoint_count;
241 spin_unlock_irqrestore(&count_lock, flags);
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));
252 if (cptype == CT_NONE)
253 return -EINVAL;
254
255 for (i = 0; i < ARRAY_SIZE(cp_name); i++) {
256 if (!strcmp(cpoint_name, cp_name[i])) {
257 cpoint = i + 1;
258 return 0;
259 }
260 }
261
262 /* Could not find a valid crash point */
263 return -EINVAL;
264}
265
266static 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
278static void lkdtm_do_action(enum ctype which)
279{
280 switch (which) {
281 case CT_PANIC:
282 panic("dumptest");
283 break;
284 case CT_BUG:
285 BUG();
286 break;
287 case CT_EXCEPTION:
288 *((int *) 0) = 0;
289 break;
290 case CT_LOOP:
291 for (;;)
292 ;
293 break;
294 case CT_OVERFLOW:
295 (void) recursive_loop(0);
296 break;
297 case CT_CORRUPT_STACK: {
298 volatile u32 data[8];
299 volatile u32 *p = data;
300
301 p[12] = 0x12345678;
302 break;
303 }
304 case CT_UNALIGNED_LOAD_STORE_WRITE: {
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 }
316 case CT_OVERWRITE_ALLOCATION: {
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 }
324 case CT_WRITE_AFTER_FREE: {
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 }
333 case CT_SOFTLOCKUP:
334 preempt_disable();
335 for (;;)
336 cpu_relax();
337 break;
338 case CT_HARDLOCKUP:
339 local_irq_disable();
340 for (;;)
341 cpu_relax();
342 break;
343 case CT_HUNG_TASK:
344 set_current_state(TASK_UNINTERRUPTIBLE);
345 schedule();
346 break;
347 case CT_NONE:
348 default:
349 break;
350 }
351
352}
353
354static void lkdtm_handler(void)
355{
356 unsigned long flags;
357
358 spin_lock_irqsave(&count_lock, flags);
359 count--;
360 printk(KERN_INFO "lkdtm: Crash point %s of type %s hit, trigger in %d rounds\n",
361 cp_name_to_str(cpoint), cp_type_to_str(cptype), count);
362
363 if (count == 0) {
364 lkdtm_do_action(cptype);
365 count = cpoint_count;
366 }
367 spin_unlock_irqrestore(&count_lock, flags);
368}
369
370static int lkdtm_register_cpoint(enum cname which)
371{
372 int ret;
373
374 cpoint = CN_INVALID;
375 if (lkdtm.entry != NULL)
376 unregister_jprobe(&lkdtm);
377
378 switch (which) {
379 case CN_DIRECT:
380 lkdtm_do_action(cptype);
381 return 0;
382 case CN_INT_HARDWARE_ENTRY:
383 lkdtm.kp.symbol_name = "do_IRQ";
384 lkdtm.entry = (kprobe_opcode_t*) jp_do_irq;
385 break;
386 case CN_INT_HW_IRQ_EN:
387 lkdtm.kp.symbol_name = "handle_IRQ_event";
388 lkdtm.entry = (kprobe_opcode_t*) jp_handle_irq_event;
389 break;
390 case CN_INT_TASKLET_ENTRY:
391 lkdtm.kp.symbol_name = "tasklet_action";
392 lkdtm.entry = (kprobe_opcode_t*) jp_tasklet_action;
393 break;
394 case CN_FS_DEVRW:
395 lkdtm.kp.symbol_name = "ll_rw_block";
396 lkdtm.entry = (kprobe_opcode_t*) jp_ll_rw_block;
397 break;
398 case CN_MEM_SWAPOUT:
399 lkdtm.kp.symbol_name = "shrink_inactive_list";
400 lkdtm.entry = (kprobe_opcode_t*) jp_shrink_inactive_list;
401 break;
402 case CN_TIMERADD:
403 lkdtm.kp.symbol_name = "hrtimer_start";
404 lkdtm.entry = (kprobe_opcode_t*) jp_hrtimer_start;
405 break;
406 case CN_SCSI_DISPATCH_CMD:
407 lkdtm.kp.symbol_name = "scsi_dispatch_cmd";
408 lkdtm.entry = (kprobe_opcode_t*) jp_scsi_dispatch_cmd;
409 break;
410 case CN_IDE_CORE_CP:
411#ifdef CONFIG_IDE
412 lkdtm.kp.symbol_name = "generic_ide_ioctl";
413 lkdtm.entry = (kprobe_opcode_t*) jp_generic_ide_ioctl;
414#else
415 printk(KERN_INFO "lkdtm: Crash point not available\n");
416 return -EINVAL;
417#endif
418 break;
419 default:
420 printk(KERN_INFO "lkdtm: Invalid Crash Point\n");
421 return -EINVAL;
422 }
423
424 cpoint = which;
425 if ((ret = register_jprobe(&lkdtm)) < 0) {
426 printk(KERN_INFO "lkdtm: Couldn't register jprobe\n");
427 cpoint = CN_INVALID;
428 }
429
430 return ret;
431}
432
433static ssize_t do_register_entry(enum cname which, struct file *f,
434 const char __user *user_buf, size_t count, loff_t *off)
435{
436 char *buf;
437 int err;
438
439 if (count >= PAGE_SIZE)
440 return -EINVAL;
441
442 buf = (char *)__get_free_page(GFP_KERNEL);
443 if (!buf)
444 return -ENOMEM;
445 if (copy_from_user(buf, user_buf, count)) {
446 free_page((unsigned long) buf);
447 return -EFAULT;
448 }
449 /* NULL-terminate and remove enter */
450 buf[count] = '\0';
451 strim(buf);
452
453 cptype = parse_cp_type(buf, count);
454 free_page((unsigned long) buf);
455
456 if (cptype == CT_NONE)
457 return -EINVAL;
458
459 err = lkdtm_register_cpoint(which);
460 if (err < 0)
461 return err;
462
463 *off += count;
464
465 return count;
466}
467
468/* Generic read callback that just prints out the available crash types */
469static ssize_t lkdtm_debugfs_read(struct file *f, char __user *user_buf,
470 size_t count, loff_t *off)
471{
472 char *buf;
473 int i, n, out;
474
475 buf = (char *)__get_free_page(GFP_KERNEL);
476
477 n = snprintf(buf, PAGE_SIZE, "Available crash types:\n");
478 for (i = 0; i < ARRAY_SIZE(cp_type); i++)
479 n += snprintf(buf + n, PAGE_SIZE - n, "%s\n", cp_type[i]);
480 buf[n] = '\0';
481
482 out = simple_read_from_buffer(user_buf, count, off,
483 buf, n);
484 free_page((unsigned long) buf);
485
486 return out;
487}
488
489static int lkdtm_debugfs_open(struct inode *inode, struct file *file)
490{
491 return 0;
492}
493
494
495static ssize_t int_hardware_entry(struct file *f, const char __user *buf,
496 size_t count, loff_t *off)
497{
498 return do_register_entry(CN_INT_HARDWARE_ENTRY, f, buf, count, off);
499}
500
501static ssize_t int_hw_irq_en(struct file *f, const char __user *buf,
502 size_t count, loff_t *off)
503{
504 return do_register_entry(CN_INT_HW_IRQ_EN, f, buf, count, off);
505}
506
507static ssize_t int_tasklet_entry(struct file *f, const char __user *buf,
508 size_t count, loff_t *off)
509{
510 return do_register_entry(CN_INT_TASKLET_ENTRY, f, buf, count, off);
511}
512
513static ssize_t fs_devrw_entry(struct file *f, const char __user *buf,
514 size_t count, loff_t *off)
515{
516 return do_register_entry(CN_FS_DEVRW, f, buf, count, off);
517}
518
519static ssize_t mem_swapout_entry(struct file *f, const char __user *buf,
520 size_t count, loff_t *off)
521{
522 return do_register_entry(CN_MEM_SWAPOUT, f, buf, count, off);
523}
524
525static ssize_t timeradd_entry(struct file *f, const char __user *buf,
526 size_t count, loff_t *off)
527{
528 return do_register_entry(CN_TIMERADD, f, buf, count, off);
529}
530
531static ssize_t scsi_dispatch_cmd_entry(struct file *f,
532 const char __user *buf, size_t count, loff_t *off)
533{
534 return do_register_entry(CN_SCSI_DISPATCH_CMD, f, buf, count, off);
535}
536
537static ssize_t ide_core_cp_entry(struct file *f, const char __user *buf,
538 size_t count, loff_t *off)
539{
540 return do_register_entry(CN_IDE_CORE_CP, f, buf, count, off);
541}
542
543/* Special entry to just crash directly. Available without KPROBEs */
544static ssize_t direct_entry(struct file *f, const char __user *user_buf,
545 size_t count, loff_t *off)
546{
547 enum ctype type;
548 char *buf;
549
550 if (count >= PAGE_SIZE)
551 return -EINVAL;
552 if (count < 1)
553 return -EINVAL;
554
555 buf = (char *)__get_free_page(GFP_KERNEL);
556 if (!buf)
557 return -ENOMEM;
558 if (copy_from_user(buf, user_buf, count)) {
559 free_page((unsigned long) buf);
560 return -EFAULT;
561 }
562 /* NULL-terminate and remove enter */
563 buf[count] = '\0';
564 strim(buf);
565
566 type = parse_cp_type(buf, count);
567 free_page((unsigned long) buf);
568 if (type == CT_NONE)
569 return -EINVAL;
570
571 printk(KERN_INFO "lkdtm: Performing direct entry %s\n",
572 cp_type_to_str(type));
573 lkdtm_do_action(type);
574 *off += count;
575
576 return count;
577}
578
579struct crash_entry {
580 const char *name;
581 const struct file_operations fops;
582};
583
584static const struct crash_entry crash_entries[] = {
585 {"DIRECT", {.read = lkdtm_debugfs_read,
586 .llseek = generic_file_llseek,
587 .open = lkdtm_debugfs_open,
588 .write = direct_entry} },
589 {"INT_HARDWARE_ENTRY", {.read = lkdtm_debugfs_read,
590 .llseek = generic_file_llseek,
591 .open = lkdtm_debugfs_open,
592 .write = int_hardware_entry} },
593 {"INT_HW_IRQ_EN", {.read = lkdtm_debugfs_read,
594 .llseek = generic_file_llseek,
595 .open = lkdtm_debugfs_open,
596 .write = int_hw_irq_en} },
597 {"INT_TASKLET_ENTRY", {.read = lkdtm_debugfs_read,
598 .llseek = generic_file_llseek,
599 .open = lkdtm_debugfs_open,
600 .write = int_tasklet_entry} },
601 {"FS_DEVRW", {.read = lkdtm_debugfs_read,
602 .llseek = generic_file_llseek,
603 .open = lkdtm_debugfs_open,
604 .write = fs_devrw_entry} },
605 {"MEM_SWAPOUT", {.read = lkdtm_debugfs_read,
606 .llseek = generic_file_llseek,
607 .open = lkdtm_debugfs_open,
608 .write = mem_swapout_entry} },
609 {"TIMERADD", {.read = lkdtm_debugfs_read,
610 .llseek = generic_file_llseek,
611 .open = lkdtm_debugfs_open,
612 .write = timeradd_entry} },
613 {"SCSI_DISPATCH_CMD", {.read = lkdtm_debugfs_read,
614 .llseek = generic_file_llseek,
615 .open = lkdtm_debugfs_open,
616 .write = scsi_dispatch_cmd_entry} },
617 {"IDE_CORE_CP", {.read = lkdtm_debugfs_read,
618 .llseek = generic_file_llseek,
619 .open = lkdtm_debugfs_open,
620 .write = ide_core_cp_entry} },
621};
622
623static struct dentry *lkdtm_debugfs_root;
624
625static int __init lkdtm_module_init(void)
626{
627 int ret = -EINVAL;
628 int n_debugfs_entries = 1; /* Assume only the direct entry */
629 int i;
630
631 /* Register debugfs interface */
632 lkdtm_debugfs_root = debugfs_create_dir("provoke-crash", NULL);
633 if (!lkdtm_debugfs_root) {
634 printk(KERN_ERR "lkdtm: creating root dir failed\n");
635 return -ENODEV;
636 }
637
638#ifdef CONFIG_KPROBES
639 n_debugfs_entries = ARRAY_SIZE(crash_entries);
640#endif
641
642 for (i = 0; i < n_debugfs_entries; i++) {
643 const struct crash_entry *cur = &crash_entries[i];
644 struct dentry *de;
645
646 de = debugfs_create_file(cur->name, 0644, lkdtm_debugfs_root,
647 NULL, &cur->fops);
648 if (de == NULL) {
649 printk(KERN_ERR "lkdtm: could not create %s\n",
650 cur->name);
651 goto out_err;
652 }
653 }
654
655 if (lkdtm_parse_commandline() == -EINVAL) {
656 printk(KERN_INFO "lkdtm: Invalid command\n");
657 goto out_err;
658 }
659
660 if (cpoint != CN_INVALID && cptype != CT_NONE) {
661 ret = lkdtm_register_cpoint(cpoint);
662 if (ret < 0) {
663 printk(KERN_INFO "lkdtm: Invalid crash point %d\n",
664 cpoint);
665 goto out_err;
666 }
667 printk(KERN_INFO "lkdtm: Crash point %s of type %s registered\n",
668 cpoint_name, cpoint_type);
669 } else {
670 printk(KERN_INFO "lkdtm: No crash points registered, enable through debugfs\n");
671 }
672
673 return 0;
674
675out_err:
676 debugfs_remove_recursive(lkdtm_debugfs_root);
677 return ret;
678}
679
680static void __exit lkdtm_module_exit(void)
681{
682 debugfs_remove_recursive(lkdtm_debugfs_root);
683
684 unregister_jprobe(&lkdtm);
685 printk(KERN_INFO "lkdtm: Crash point unregistered\n");
686}
687
688module_init(lkdtm_module_init);
689module_exit(lkdtm_module_exit);
690
691MODULE_LICENSE("GPL");
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 *
29 * Debugfs support added by Simon Kagstrom <simon.kagstrom@netinsight.net>
30 *
31 * See Documentation/fault-injection/provoke-crashes.txt for instructions
32 */
33#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
34
35#include <linux/kernel.h>
36#include <linux/fs.h>
37#include <linux/module.h>
38#include <linux/buffer_head.h>
39#include <linux/kprobes.h>
40#include <linux/list.h>
41#include <linux/init.h>
42#include <linux/interrupt.h>
43#include <linux/hrtimer.h>
44#include <linux/slab.h>
45#include <scsi/scsi_cmnd.h>
46#include <linux/debugfs.h>
47#include <linux/vmalloc.h>
48#include <linux/mman.h>
49#include <asm/cacheflush.h>
50
51#ifdef CONFIG_IDE
52#include <linux/ide.h>
53#endif
54
55/*
56 * Make sure our attempts to over run the kernel stack doesn't trigger
57 * a compiler warning when CONFIG_FRAME_WARN is set. Then make sure we
58 * recurse past the end of THREAD_SIZE by default.
59 */
60#if defined(CONFIG_FRAME_WARN) && (CONFIG_FRAME_WARN > 0)
61#define REC_STACK_SIZE (CONFIG_FRAME_WARN / 2)
62#else
63#define REC_STACK_SIZE (THREAD_SIZE / 8)
64#endif
65#define REC_NUM_DEFAULT ((THREAD_SIZE / REC_STACK_SIZE) * 2)
66
67#define DEFAULT_COUNT 10
68#define EXEC_SIZE 64
69
70enum cname {
71 CN_INVALID,
72 CN_INT_HARDWARE_ENTRY,
73 CN_INT_HW_IRQ_EN,
74 CN_INT_TASKLET_ENTRY,
75 CN_FS_DEVRW,
76 CN_MEM_SWAPOUT,
77 CN_TIMERADD,
78 CN_SCSI_DISPATCH_CMD,
79 CN_IDE_CORE_CP,
80 CN_DIRECT,
81};
82
83enum ctype {
84 CT_NONE,
85 CT_PANIC,
86 CT_BUG,
87 CT_WARNING,
88 CT_EXCEPTION,
89 CT_LOOP,
90 CT_OVERFLOW,
91 CT_CORRUPT_STACK,
92 CT_UNALIGNED_LOAD_STORE_WRITE,
93 CT_OVERWRITE_ALLOCATION,
94 CT_WRITE_AFTER_FREE,
95 CT_SOFTLOCKUP,
96 CT_HARDLOCKUP,
97 CT_SPINLOCKUP,
98 CT_HUNG_TASK,
99 CT_EXEC_DATA,
100 CT_EXEC_STACK,
101 CT_EXEC_KMALLOC,
102 CT_EXEC_VMALLOC,
103 CT_EXEC_USERSPACE,
104 CT_ACCESS_USERSPACE,
105 CT_WRITE_RO,
106 CT_WRITE_KERN,
107};
108
109static char* cp_name[] = {
110 "INT_HARDWARE_ENTRY",
111 "INT_HW_IRQ_EN",
112 "INT_TASKLET_ENTRY",
113 "FS_DEVRW",
114 "MEM_SWAPOUT",
115 "TIMERADD",
116 "SCSI_DISPATCH_CMD",
117 "IDE_CORE_CP",
118 "DIRECT",
119};
120
121static char* cp_type[] = {
122 "PANIC",
123 "BUG",
124 "WARNING",
125 "EXCEPTION",
126 "LOOP",
127 "OVERFLOW",
128 "CORRUPT_STACK",
129 "UNALIGNED_LOAD_STORE_WRITE",
130 "OVERWRITE_ALLOCATION",
131 "WRITE_AFTER_FREE",
132 "SOFTLOCKUP",
133 "HARDLOCKUP",
134 "SPINLOCKUP",
135 "HUNG_TASK",
136 "EXEC_DATA",
137 "EXEC_STACK",
138 "EXEC_KMALLOC",
139 "EXEC_VMALLOC",
140 "EXEC_USERSPACE",
141 "ACCESS_USERSPACE",
142 "WRITE_RO",
143 "WRITE_KERN",
144};
145
146static struct jprobe lkdtm;
147
148static int lkdtm_parse_commandline(void);
149static void lkdtm_handler(void);
150
151static char* cpoint_name;
152static char* cpoint_type;
153static int cpoint_count = DEFAULT_COUNT;
154static int recur_count = REC_NUM_DEFAULT;
155
156static enum cname cpoint = CN_INVALID;
157static enum ctype cptype = CT_NONE;
158static int count = DEFAULT_COUNT;
159static DEFINE_SPINLOCK(count_lock);
160static DEFINE_SPINLOCK(lock_me_up);
161
162static u8 data_area[EXEC_SIZE];
163
164static const unsigned long rodata = 0xAA55AA55;
165
166module_param(recur_count, int, 0644);
167MODULE_PARM_DESC(recur_count, " Recursion level for the stack overflow test");
168module_param(cpoint_name, charp, 0444);
169MODULE_PARM_DESC(cpoint_name, " Crash Point, where kernel is to be crashed");
170module_param(cpoint_type, charp, 0444);
171MODULE_PARM_DESC(cpoint_type, " Crash Point Type, action to be taken on "\
172 "hitting the crash point");
173module_param(cpoint_count, int, 0644);
174MODULE_PARM_DESC(cpoint_count, " Crash Point Count, number of times the "\
175 "crash point is to be hit to trigger action");
176
177static unsigned int jp_do_irq(unsigned int irq)
178{
179 lkdtm_handler();
180 jprobe_return();
181 return 0;
182}
183
184static irqreturn_t jp_handle_irq_event(unsigned int irq,
185 struct irqaction *action)
186{
187 lkdtm_handler();
188 jprobe_return();
189 return 0;
190}
191
192static void jp_tasklet_action(struct softirq_action *a)
193{
194 lkdtm_handler();
195 jprobe_return();
196}
197
198static void jp_ll_rw_block(int rw, int nr, struct buffer_head *bhs[])
199{
200 lkdtm_handler();
201 jprobe_return();
202}
203
204struct scan_control;
205
206static unsigned long jp_shrink_inactive_list(unsigned long max_scan,
207 struct zone *zone,
208 struct scan_control *sc)
209{
210 lkdtm_handler();
211 jprobe_return();
212 return 0;
213}
214
215static int jp_hrtimer_start(struct hrtimer *timer, ktime_t tim,
216 const enum hrtimer_mode mode)
217{
218 lkdtm_handler();
219 jprobe_return();
220 return 0;
221}
222
223static int jp_scsi_dispatch_cmd(struct scsi_cmnd *cmd)
224{
225 lkdtm_handler();
226 jprobe_return();
227 return 0;
228}
229
230#ifdef CONFIG_IDE
231static int jp_generic_ide_ioctl(ide_drive_t *drive, struct file *file,
232 struct block_device *bdev, unsigned int cmd,
233 unsigned long arg)
234{
235 lkdtm_handler();
236 jprobe_return();
237 return 0;
238}
239#endif
240
241/* Return the crashpoint number or NONE if the name is invalid */
242static enum ctype parse_cp_type(const char *what, size_t count)
243{
244 int i;
245
246 for (i = 0; i < ARRAY_SIZE(cp_type); i++) {
247 if (!strcmp(what, cp_type[i]))
248 return i + 1;
249 }
250
251 return CT_NONE;
252}
253
254static const char *cp_type_to_str(enum ctype type)
255{
256 if (type == CT_NONE || type < 0 || type > ARRAY_SIZE(cp_type))
257 return "None";
258
259 return cp_type[type - 1];
260}
261
262static const char *cp_name_to_str(enum cname name)
263{
264 if (name == CN_INVALID || name < 0 || name > ARRAY_SIZE(cp_name))
265 return "INVALID";
266
267 return cp_name[name - 1];
268}
269
270
271static int lkdtm_parse_commandline(void)
272{
273 int i;
274 unsigned long flags;
275
276 if (cpoint_count < 1 || recur_count < 1)
277 return -EINVAL;
278
279 spin_lock_irqsave(&count_lock, flags);
280 count = cpoint_count;
281 spin_unlock_irqrestore(&count_lock, flags);
282
283 /* No special parameters */
284 if (!cpoint_type && !cpoint_name)
285 return 0;
286
287 /* Neither or both of these need to be set */
288 if (!cpoint_type || !cpoint_name)
289 return -EINVAL;
290
291 cptype = parse_cp_type(cpoint_type, strlen(cpoint_type));
292 if (cptype == CT_NONE)
293 return -EINVAL;
294
295 for (i = 0; i < ARRAY_SIZE(cp_name); i++) {
296 if (!strcmp(cpoint_name, cp_name[i])) {
297 cpoint = i + 1;
298 return 0;
299 }
300 }
301
302 /* Could not find a valid crash point */
303 return -EINVAL;
304}
305
306static int recursive_loop(int remaining)
307{
308 char buf[REC_STACK_SIZE];
309
310 /* Make sure compiler does not optimize this away. */
311 memset(buf, (remaining & 0xff) | 0x1, REC_STACK_SIZE);
312 if (!remaining)
313 return 0;
314 else
315 return recursive_loop(remaining - 1);
316}
317
318static void do_nothing(void)
319{
320 return;
321}
322
323/* Must immediately follow do_nothing for size calculuations to work out. */
324static void do_overwritten(void)
325{
326 pr_info("do_overwritten wasn't overwritten!\n");
327 return;
328}
329
330static noinline void corrupt_stack(void)
331{
332 /* Use default char array length that triggers stack protection. */
333 char data[8];
334
335 memset((void *)data, 0, 64);
336}
337
338static void execute_location(void *dst)
339{
340 void (*func)(void) = dst;
341
342 pr_info("attempting ok execution at %p\n", do_nothing);
343 do_nothing();
344
345 memcpy(dst, do_nothing, EXEC_SIZE);
346 flush_icache_range((unsigned long)dst, (unsigned long)dst + EXEC_SIZE);
347 pr_info("attempting bad execution at %p\n", func);
348 func();
349}
350
351static void execute_user_location(void *dst)
352{
353 /* Intentionally crossing kernel/user memory boundary. */
354 void (*func)(void) = dst;
355
356 pr_info("attempting ok execution at %p\n", do_nothing);
357 do_nothing();
358
359 if (copy_to_user((void __user *)dst, do_nothing, EXEC_SIZE))
360 return;
361 flush_icache_range((unsigned long)dst, (unsigned long)dst + EXEC_SIZE);
362 pr_info("attempting bad execution at %p\n", func);
363 func();
364}
365
366static void lkdtm_do_action(enum ctype which)
367{
368 switch (which) {
369 case CT_PANIC:
370 panic("dumptest");
371 break;
372 case CT_BUG:
373 BUG();
374 break;
375 case CT_WARNING:
376 WARN_ON(1);
377 break;
378 case CT_EXCEPTION:
379 *((int *) 0) = 0;
380 break;
381 case CT_LOOP:
382 for (;;)
383 ;
384 break;
385 case CT_OVERFLOW:
386 (void) recursive_loop(recur_count);
387 break;
388 case CT_CORRUPT_STACK:
389 corrupt_stack();
390 break;
391 case CT_UNALIGNED_LOAD_STORE_WRITE: {
392 static u8 data[5] __attribute__((aligned(4))) = {1, 2,
393 3, 4, 5};
394 u32 *p;
395 u32 val = 0x12345678;
396
397 p = (u32 *)(data + 1);
398 if (*p == 0)
399 val = 0x87654321;
400 *p = val;
401 break;
402 }
403 case CT_OVERWRITE_ALLOCATION: {
404 size_t len = 1020;
405 u32 *data = kmalloc(len, GFP_KERNEL);
406
407 data[1024 / sizeof(u32)] = 0x12345678;
408 kfree(data);
409 break;
410 }
411 case CT_WRITE_AFTER_FREE: {
412 size_t len = 1024;
413 u32 *data = kmalloc(len, GFP_KERNEL);
414
415 kfree(data);
416 schedule();
417 memset(data, 0x78, len);
418 break;
419 }
420 case CT_SOFTLOCKUP:
421 preempt_disable();
422 for (;;)
423 cpu_relax();
424 break;
425 case CT_HARDLOCKUP:
426 local_irq_disable();
427 for (;;)
428 cpu_relax();
429 break;
430 case CT_SPINLOCKUP:
431 /* Must be called twice to trigger. */
432 spin_lock(&lock_me_up);
433 /* Let sparse know we intended to exit holding the lock. */
434 __release(&lock_me_up);
435 break;
436 case CT_HUNG_TASK:
437 set_current_state(TASK_UNINTERRUPTIBLE);
438 schedule();
439 break;
440 case CT_EXEC_DATA:
441 execute_location(data_area);
442 break;
443 case CT_EXEC_STACK: {
444 u8 stack_area[EXEC_SIZE];
445 execute_location(stack_area);
446 break;
447 }
448 case CT_EXEC_KMALLOC: {
449 u32 *kmalloc_area = kmalloc(EXEC_SIZE, GFP_KERNEL);
450 execute_location(kmalloc_area);
451 kfree(kmalloc_area);
452 break;
453 }
454 case CT_EXEC_VMALLOC: {
455 u32 *vmalloc_area = vmalloc(EXEC_SIZE);
456 execute_location(vmalloc_area);
457 vfree(vmalloc_area);
458 break;
459 }
460 case CT_EXEC_USERSPACE: {
461 unsigned long user_addr;
462
463 user_addr = vm_mmap(NULL, 0, PAGE_SIZE,
464 PROT_READ | PROT_WRITE | PROT_EXEC,
465 MAP_ANONYMOUS | MAP_PRIVATE, 0);
466 if (user_addr >= TASK_SIZE) {
467 pr_warn("Failed to allocate user memory\n");
468 return;
469 }
470 execute_user_location((void *)user_addr);
471 vm_munmap(user_addr, PAGE_SIZE);
472 break;
473 }
474 case CT_ACCESS_USERSPACE: {
475 unsigned long user_addr, tmp;
476 unsigned long *ptr;
477
478 user_addr = vm_mmap(NULL, 0, PAGE_SIZE,
479 PROT_READ | PROT_WRITE | PROT_EXEC,
480 MAP_ANONYMOUS | MAP_PRIVATE, 0);
481 if (user_addr >= TASK_SIZE) {
482 pr_warn("Failed to allocate user memory\n");
483 return;
484 }
485
486 ptr = (unsigned long *)user_addr;
487
488 pr_info("attempting bad read at %p\n", ptr);
489 tmp = *ptr;
490 tmp += 0xc0dec0de;
491
492 pr_info("attempting bad write at %p\n", ptr);
493 *ptr = tmp;
494
495 vm_munmap(user_addr, PAGE_SIZE);
496
497 break;
498 }
499 case CT_WRITE_RO: {
500 unsigned long *ptr;
501
502 ptr = (unsigned long *)&rodata;
503
504 pr_info("attempting bad write at %p\n", ptr);
505 *ptr ^= 0xabcd1234;
506
507 break;
508 }
509 case CT_WRITE_KERN: {
510 size_t size;
511 unsigned char *ptr;
512
513 size = (unsigned long)do_overwritten -
514 (unsigned long)do_nothing;
515 ptr = (unsigned char *)do_overwritten;
516
517 pr_info("attempting bad %zu byte write at %p\n", size, ptr);
518 memcpy(ptr, (unsigned char *)do_nothing, size);
519 flush_icache_range((unsigned long)ptr,
520 (unsigned long)(ptr + size));
521
522 do_overwritten();
523 break;
524 }
525 case CT_NONE:
526 default:
527 break;
528 }
529
530}
531
532static void lkdtm_handler(void)
533{
534 unsigned long flags;
535 bool do_it = false;
536
537 spin_lock_irqsave(&count_lock, flags);
538 count--;
539 pr_info("Crash point %s of type %s hit, trigger in %d rounds\n",
540 cp_name_to_str(cpoint), cp_type_to_str(cptype), count);
541
542 if (count == 0) {
543 do_it = true;
544 count = cpoint_count;
545 }
546 spin_unlock_irqrestore(&count_lock, flags);
547
548 if (do_it)
549 lkdtm_do_action(cptype);
550}
551
552static int lkdtm_register_cpoint(enum cname which)
553{
554 int ret;
555
556 cpoint = CN_INVALID;
557 if (lkdtm.entry != NULL)
558 unregister_jprobe(&lkdtm);
559
560 switch (which) {
561 case CN_DIRECT:
562 lkdtm_do_action(cptype);
563 return 0;
564 case CN_INT_HARDWARE_ENTRY:
565 lkdtm.kp.symbol_name = "do_IRQ";
566 lkdtm.entry = (kprobe_opcode_t*) jp_do_irq;
567 break;
568 case CN_INT_HW_IRQ_EN:
569 lkdtm.kp.symbol_name = "handle_IRQ_event";
570 lkdtm.entry = (kprobe_opcode_t*) jp_handle_irq_event;
571 break;
572 case CN_INT_TASKLET_ENTRY:
573 lkdtm.kp.symbol_name = "tasklet_action";
574 lkdtm.entry = (kprobe_opcode_t*) jp_tasklet_action;
575 break;
576 case CN_FS_DEVRW:
577 lkdtm.kp.symbol_name = "ll_rw_block";
578 lkdtm.entry = (kprobe_opcode_t*) jp_ll_rw_block;
579 break;
580 case CN_MEM_SWAPOUT:
581 lkdtm.kp.symbol_name = "shrink_inactive_list";
582 lkdtm.entry = (kprobe_opcode_t*) jp_shrink_inactive_list;
583 break;
584 case CN_TIMERADD:
585 lkdtm.kp.symbol_name = "hrtimer_start";
586 lkdtm.entry = (kprobe_opcode_t*) jp_hrtimer_start;
587 break;
588 case CN_SCSI_DISPATCH_CMD:
589 lkdtm.kp.symbol_name = "scsi_dispatch_cmd";
590 lkdtm.entry = (kprobe_opcode_t*) jp_scsi_dispatch_cmd;
591 break;
592 case CN_IDE_CORE_CP:
593#ifdef CONFIG_IDE
594 lkdtm.kp.symbol_name = "generic_ide_ioctl";
595 lkdtm.entry = (kprobe_opcode_t*) jp_generic_ide_ioctl;
596#else
597 pr_info("Crash point not available\n");
598 return -EINVAL;
599#endif
600 break;
601 default:
602 pr_info("Invalid Crash Point\n");
603 return -EINVAL;
604 }
605
606 cpoint = which;
607 if ((ret = register_jprobe(&lkdtm)) < 0) {
608 pr_info("Couldn't register jprobe\n");
609 cpoint = CN_INVALID;
610 }
611
612 return ret;
613}
614
615static ssize_t do_register_entry(enum cname which, struct file *f,
616 const char __user *user_buf, size_t count, loff_t *off)
617{
618 char *buf;
619 int err;
620
621 if (count >= PAGE_SIZE)
622 return -EINVAL;
623
624 buf = (char *)__get_free_page(GFP_KERNEL);
625 if (!buf)
626 return -ENOMEM;
627 if (copy_from_user(buf, user_buf, count)) {
628 free_page((unsigned long) buf);
629 return -EFAULT;
630 }
631 /* NULL-terminate and remove enter */
632 buf[count] = '\0';
633 strim(buf);
634
635 cptype = parse_cp_type(buf, count);
636 free_page((unsigned long) buf);
637
638 if (cptype == CT_NONE)
639 return -EINVAL;
640
641 err = lkdtm_register_cpoint(which);
642 if (err < 0)
643 return err;
644
645 *off += count;
646
647 return count;
648}
649
650/* Generic read callback that just prints out the available crash types */
651static ssize_t lkdtm_debugfs_read(struct file *f, char __user *user_buf,
652 size_t count, loff_t *off)
653{
654 char *buf;
655 int i, n, out;
656
657 buf = (char *)__get_free_page(GFP_KERNEL);
658 if (buf == NULL)
659 return -ENOMEM;
660
661 n = snprintf(buf, PAGE_SIZE, "Available crash types:\n");
662 for (i = 0; i < ARRAY_SIZE(cp_type); i++)
663 n += snprintf(buf + n, PAGE_SIZE - n, "%s\n", cp_type[i]);
664 buf[n] = '\0';
665
666 out = simple_read_from_buffer(user_buf, count, off,
667 buf, n);
668 free_page((unsigned long) buf);
669
670 return out;
671}
672
673static int lkdtm_debugfs_open(struct inode *inode, struct file *file)
674{
675 return 0;
676}
677
678
679static ssize_t int_hardware_entry(struct file *f, const char __user *buf,
680 size_t count, loff_t *off)
681{
682 return do_register_entry(CN_INT_HARDWARE_ENTRY, f, buf, count, off);
683}
684
685static ssize_t int_hw_irq_en(struct file *f, const char __user *buf,
686 size_t count, loff_t *off)
687{
688 return do_register_entry(CN_INT_HW_IRQ_EN, f, buf, count, off);
689}
690
691static ssize_t int_tasklet_entry(struct file *f, const char __user *buf,
692 size_t count, loff_t *off)
693{
694 return do_register_entry(CN_INT_TASKLET_ENTRY, f, buf, count, off);
695}
696
697static ssize_t fs_devrw_entry(struct file *f, const char __user *buf,
698 size_t count, loff_t *off)
699{
700 return do_register_entry(CN_FS_DEVRW, f, buf, count, off);
701}
702
703static ssize_t mem_swapout_entry(struct file *f, const char __user *buf,
704 size_t count, loff_t *off)
705{
706 return do_register_entry(CN_MEM_SWAPOUT, f, buf, count, off);
707}
708
709static ssize_t timeradd_entry(struct file *f, const char __user *buf,
710 size_t count, loff_t *off)
711{
712 return do_register_entry(CN_TIMERADD, f, buf, count, off);
713}
714
715static ssize_t scsi_dispatch_cmd_entry(struct file *f,
716 const char __user *buf, size_t count, loff_t *off)
717{
718 return do_register_entry(CN_SCSI_DISPATCH_CMD, f, buf, count, off);
719}
720
721static ssize_t ide_core_cp_entry(struct file *f, const char __user *buf,
722 size_t count, loff_t *off)
723{
724 return do_register_entry(CN_IDE_CORE_CP, f, buf, count, off);
725}
726
727/* Special entry to just crash directly. Available without KPROBEs */
728static ssize_t direct_entry(struct file *f, const char __user *user_buf,
729 size_t count, loff_t *off)
730{
731 enum ctype type;
732 char *buf;
733
734 if (count >= PAGE_SIZE)
735 return -EINVAL;
736 if (count < 1)
737 return -EINVAL;
738
739 buf = (char *)__get_free_page(GFP_KERNEL);
740 if (!buf)
741 return -ENOMEM;
742 if (copy_from_user(buf, user_buf, count)) {
743 free_page((unsigned long) buf);
744 return -EFAULT;
745 }
746 /* NULL-terminate and remove enter */
747 buf[count] = '\0';
748 strim(buf);
749
750 type = parse_cp_type(buf, count);
751 free_page((unsigned long) buf);
752 if (type == CT_NONE)
753 return -EINVAL;
754
755 pr_info("Performing direct entry %s\n", cp_type_to_str(type));
756 lkdtm_do_action(type);
757 *off += count;
758
759 return count;
760}
761
762struct crash_entry {
763 const char *name;
764 const struct file_operations fops;
765};
766
767static const struct crash_entry crash_entries[] = {
768 {"DIRECT", {.read = lkdtm_debugfs_read,
769 .llseek = generic_file_llseek,
770 .open = lkdtm_debugfs_open,
771 .write = direct_entry} },
772 {"INT_HARDWARE_ENTRY", {.read = lkdtm_debugfs_read,
773 .llseek = generic_file_llseek,
774 .open = lkdtm_debugfs_open,
775 .write = int_hardware_entry} },
776 {"INT_HW_IRQ_EN", {.read = lkdtm_debugfs_read,
777 .llseek = generic_file_llseek,
778 .open = lkdtm_debugfs_open,
779 .write = int_hw_irq_en} },
780 {"INT_TASKLET_ENTRY", {.read = lkdtm_debugfs_read,
781 .llseek = generic_file_llseek,
782 .open = lkdtm_debugfs_open,
783 .write = int_tasklet_entry} },
784 {"FS_DEVRW", {.read = lkdtm_debugfs_read,
785 .llseek = generic_file_llseek,
786 .open = lkdtm_debugfs_open,
787 .write = fs_devrw_entry} },
788 {"MEM_SWAPOUT", {.read = lkdtm_debugfs_read,
789 .llseek = generic_file_llseek,
790 .open = lkdtm_debugfs_open,
791 .write = mem_swapout_entry} },
792 {"TIMERADD", {.read = lkdtm_debugfs_read,
793 .llseek = generic_file_llseek,
794 .open = lkdtm_debugfs_open,
795 .write = timeradd_entry} },
796 {"SCSI_DISPATCH_CMD", {.read = lkdtm_debugfs_read,
797 .llseek = generic_file_llseek,
798 .open = lkdtm_debugfs_open,
799 .write = scsi_dispatch_cmd_entry} },
800 {"IDE_CORE_CP", {.read = lkdtm_debugfs_read,
801 .llseek = generic_file_llseek,
802 .open = lkdtm_debugfs_open,
803 .write = ide_core_cp_entry} },
804};
805
806static struct dentry *lkdtm_debugfs_root;
807
808static int __init lkdtm_module_init(void)
809{
810 int ret = -EINVAL;
811 int n_debugfs_entries = 1; /* Assume only the direct entry */
812 int i;
813
814 /* Register debugfs interface */
815 lkdtm_debugfs_root = debugfs_create_dir("provoke-crash", NULL);
816 if (!lkdtm_debugfs_root) {
817 pr_err("creating root dir failed\n");
818 return -ENODEV;
819 }
820
821#ifdef CONFIG_KPROBES
822 n_debugfs_entries = ARRAY_SIZE(crash_entries);
823#endif
824
825 for (i = 0; i < n_debugfs_entries; i++) {
826 const struct crash_entry *cur = &crash_entries[i];
827 struct dentry *de;
828
829 de = debugfs_create_file(cur->name, 0644, lkdtm_debugfs_root,
830 NULL, &cur->fops);
831 if (de == NULL) {
832 pr_err("could not create %s\n", cur->name);
833 goto out_err;
834 }
835 }
836
837 if (lkdtm_parse_commandline() == -EINVAL) {
838 pr_info("Invalid command\n");
839 goto out_err;
840 }
841
842 if (cpoint != CN_INVALID && cptype != CT_NONE) {
843 ret = lkdtm_register_cpoint(cpoint);
844 if (ret < 0) {
845 pr_info("Invalid crash point %d\n", cpoint);
846 goto out_err;
847 }
848 pr_info("Crash point %s of type %s registered\n",
849 cpoint_name, cpoint_type);
850 } else {
851 pr_info("No crash points registered, enable through debugfs\n");
852 }
853
854 return 0;
855
856out_err:
857 debugfs_remove_recursive(lkdtm_debugfs_root);
858 return ret;
859}
860
861static void __exit lkdtm_module_exit(void)
862{
863 debugfs_remove_recursive(lkdtm_debugfs_root);
864
865 unregister_jprobe(&lkdtm);
866 pr_info("Crash point unregistered\n");
867}
868
869module_init(lkdtm_module_init);
870module_exit(lkdtm_module_exit);
871
872MODULE_LICENSE("GPL");