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> |
9ae113ce | 47 | #include <linux/mman.h> |
8bb31b9d AG |
48 | |
49 | #ifdef CONFIG_IDE | |
50 | #include <linux/ide.h> | |
51 | #endif | |
52 | ||
7d196ac3 KC |
53 | /* |
54 | * Make sure our attempts to over run the kernel stack doesn't trigger | |
55 | * a compiler warning when CONFIG_FRAME_WARN is set. Then make sure we | |
56 | * recurse past the end of THREAD_SIZE by default. | |
57 | */ | |
58 | #if defined(CONFIG_FRAME_WARN) && (CONFIG_FRAME_WARN > 0) | |
59 | #define REC_STACK_SIZE (CONFIG_FRAME_WARN / 2) | |
60 | #else | |
61 | #define REC_STACK_SIZE (THREAD_SIZE / 8) | |
62 | #endif | |
63 | #define REC_NUM_DEFAULT ((THREAD_SIZE / REC_STACK_SIZE) * 2) | |
64 | ||
8bb31b9d | 65 | #define DEFAULT_COUNT 10 |
cc33c537 | 66 | #define EXEC_SIZE 64 |
8bb31b9d AG |
67 | |
68 | enum cname { | |
93e2f585 NK |
69 | CN_INVALID, |
70 | CN_INT_HARDWARE_ENTRY, | |
71 | CN_INT_HW_IRQ_EN, | |
72 | CN_INT_TASKLET_ENTRY, | |
73 | CN_FS_DEVRW, | |
74 | CN_MEM_SWAPOUT, | |
75 | CN_TIMERADD, | |
76 | CN_SCSI_DISPATCH_CMD, | |
77 | CN_IDE_CORE_CP, | |
78 | CN_DIRECT, | |
8bb31b9d AG |
79 | }; |
80 | ||
81 | enum ctype { | |
93e2f585 NK |
82 | CT_NONE, |
83 | CT_PANIC, | |
84 | CT_BUG, | |
65892723 | 85 | CT_WARNING, |
93e2f585 NK |
86 | CT_EXCEPTION, |
87 | CT_LOOP, | |
88 | CT_OVERFLOW, | |
89 | CT_CORRUPT_STACK, | |
90 | CT_UNALIGNED_LOAD_STORE_WRITE, | |
91 | CT_OVERWRITE_ALLOCATION, | |
92 | CT_WRITE_AFTER_FREE, | |
93 | CT_SOFTLOCKUP, | |
94 | CT_HARDLOCKUP, | |
274a5855 | 95 | CT_SPINLOCKUP, |
93e2f585 | 96 | CT_HUNG_TASK, |
cc33c537 KC |
97 | CT_EXEC_DATA, |
98 | CT_EXEC_STACK, | |
99 | CT_EXEC_KMALLOC, | |
100 | CT_EXEC_VMALLOC, | |
9ae113ce KC |
101 | CT_EXEC_USERSPACE, |
102 | CT_ACCESS_USERSPACE, | |
103 | CT_WRITE_RO, | |
8bb31b9d AG |
104 | }; |
105 | ||
106 | static char* cp_name[] = { | |
107 | "INT_HARDWARE_ENTRY", | |
108 | "INT_HW_IRQ_EN", | |
109 | "INT_TASKLET_ENTRY", | |
110 | "FS_DEVRW", | |
111 | "MEM_SWAPOUT", | |
112 | "TIMERADD", | |
113 | "SCSI_DISPATCH_CMD", | |
0347af4e SK |
114 | "IDE_CORE_CP", |
115 | "DIRECT", | |
8bb31b9d AG |
116 | }; |
117 | ||
118 | static char* cp_type[] = { | |
119 | "PANIC", | |
120 | "BUG", | |
65892723 | 121 | "WARNING", |
8bb31b9d AG |
122 | "EXCEPTION", |
123 | "LOOP", | |
0347af4e SK |
124 | "OVERFLOW", |
125 | "CORRUPT_STACK", | |
126 | "UNALIGNED_LOAD_STORE_WRITE", | |
127 | "OVERWRITE_ALLOCATION", | |
128 | "WRITE_AFTER_FREE", | |
a48223f9 FW |
129 | "SOFTLOCKUP", |
130 | "HARDLOCKUP", | |
274a5855 | 131 | "SPINLOCKUP", |
a48223f9 | 132 | "HUNG_TASK", |
cc33c537 KC |
133 | "EXEC_DATA", |
134 | "EXEC_STACK", | |
135 | "EXEC_KMALLOC", | |
136 | "EXEC_VMALLOC", | |
9ae113ce KC |
137 | "EXEC_USERSPACE", |
138 | "ACCESS_USERSPACE", | |
139 | "WRITE_RO", | |
8bb31b9d AG |
140 | }; |
141 | ||
142 | static struct jprobe lkdtm; | |
143 | ||
144 | static int lkdtm_parse_commandline(void); | |
145 | static void lkdtm_handler(void); | |
146 | ||
ec1c620b AV |
147 | static char* cpoint_name; |
148 | static char* cpoint_type; | |
8bb31b9d AG |
149 | static int cpoint_count = DEFAULT_COUNT; |
150 | static int recur_count = REC_NUM_DEFAULT; | |
151 | ||
93e2f585 NK |
152 | static enum cname cpoint = CN_INVALID; |
153 | static enum ctype cptype = CT_NONE; | |
8bb31b9d | 154 | static int count = DEFAULT_COUNT; |
aa2c96d6 | 155 | static DEFINE_SPINLOCK(count_lock); |
274a5855 | 156 | static DEFINE_SPINLOCK(lock_me_up); |
8bb31b9d | 157 | |
cc33c537 KC |
158 | static u8 data_area[EXEC_SIZE]; |
159 | ||
9ae113ce KC |
160 | static const unsigned long rodata = 0xAA55AA55; |
161 | ||
8bb31b9d | 162 | module_param(recur_count, int, 0644); |
7d196ac3 | 163 | MODULE_PARM_DESC(recur_count, " Recursion level for the stack overflow test"); |
dca41306 | 164 | module_param(cpoint_name, charp, 0444); |
5d861d92 | 165 | MODULE_PARM_DESC(cpoint_name, " Crash Point, where kernel is to be crashed"); |
dca41306 | 166 | module_param(cpoint_type, charp, 0444); |
5d861d92 RD |
167 | MODULE_PARM_DESC(cpoint_type, " Crash Point Type, action to be taken on "\ |
168 | "hitting the crash point"); | |
169 | module_param(cpoint_count, int, 0644); | |
170 | MODULE_PARM_DESC(cpoint_count, " Crash Point Count, number of times the "\ | |
171 | "crash point is to be hit to trigger action"); | |
8bb31b9d | 172 | |
2118116e | 173 | static unsigned int jp_do_irq(unsigned int irq) |
8bb31b9d AG |
174 | { |
175 | lkdtm_handler(); | |
176 | jprobe_return(); | |
177 | return 0; | |
178 | } | |
179 | ||
2118116e AB |
180 | static irqreturn_t jp_handle_irq_event(unsigned int irq, |
181 | struct irqaction *action) | |
8bb31b9d AG |
182 | { |
183 | lkdtm_handler(); | |
184 | jprobe_return(); | |
185 | return 0; | |
186 | } | |
187 | ||
2118116e | 188 | static void jp_tasklet_action(struct softirq_action *a) |
8bb31b9d AG |
189 | { |
190 | lkdtm_handler(); | |
191 | jprobe_return(); | |
192 | } | |
193 | ||
2118116e | 194 | static void jp_ll_rw_block(int rw, int nr, struct buffer_head *bhs[]) |
8bb31b9d AG |
195 | { |
196 | lkdtm_handler(); | |
197 | jprobe_return(); | |
198 | } | |
199 | ||
200 | struct scan_control; | |
201 | ||
2118116e AB |
202 | static unsigned long jp_shrink_inactive_list(unsigned long max_scan, |
203 | struct zone *zone, | |
204 | struct scan_control *sc) | |
8bb31b9d AG |
205 | { |
206 | lkdtm_handler(); | |
207 | jprobe_return(); | |
208 | return 0; | |
209 | } | |
210 | ||
2118116e AB |
211 | static int jp_hrtimer_start(struct hrtimer *timer, ktime_t tim, |
212 | const enum hrtimer_mode mode) | |
8bb31b9d AG |
213 | { |
214 | lkdtm_handler(); | |
215 | jprobe_return(); | |
216 | return 0; | |
217 | } | |
218 | ||
2118116e | 219 | static int jp_scsi_dispatch_cmd(struct scsi_cmnd *cmd) |
8bb31b9d AG |
220 | { |
221 | lkdtm_handler(); | |
222 | jprobe_return(); | |
223 | return 0; | |
224 | } | |
225 | ||
226 | #ifdef CONFIG_IDE | |
227 | int jp_generic_ide_ioctl(ide_drive_t *drive, struct file *file, | |
228 | struct block_device *bdev, unsigned int cmd, | |
229 | unsigned long arg) | |
230 | { | |
231 | lkdtm_handler(); | |
232 | jprobe_return(); | |
233 | return 0; | |
234 | } | |
235 | #endif | |
236 | ||
0347af4e SK |
237 | /* Return the crashpoint number or NONE if the name is invalid */ |
238 | static enum ctype parse_cp_type(const char *what, size_t count) | |
239 | { | |
240 | int i; | |
241 | ||
242 | for (i = 0; i < ARRAY_SIZE(cp_type); i++) { | |
243 | if (!strcmp(what, cp_type[i])) | |
244 | return i + 1; | |
245 | } | |
246 | ||
93e2f585 | 247 | return CT_NONE; |
0347af4e SK |
248 | } |
249 | ||
250 | static const char *cp_type_to_str(enum ctype type) | |
251 | { | |
93e2f585 | 252 | if (type == CT_NONE || type < 0 || type > ARRAY_SIZE(cp_type)) |
0347af4e SK |
253 | return "None"; |
254 | ||
255 | return cp_type[type - 1]; | |
256 | } | |
257 | ||
258 | static const char *cp_name_to_str(enum cname name) | |
259 | { | |
93e2f585 | 260 | if (name == CN_INVALID || name < 0 || name > ARRAY_SIZE(cp_name)) |
0347af4e SK |
261 | return "INVALID"; |
262 | ||
263 | return cp_name[name - 1]; | |
264 | } | |
265 | ||
266 | ||
8bb31b9d AG |
267 | static int lkdtm_parse_commandline(void) |
268 | { | |
269 | int i; | |
aa2c96d6 | 270 | unsigned long flags; |
8bb31b9d | 271 | |
0347af4e | 272 | if (cpoint_count < 1 || recur_count < 1) |
8bb31b9d AG |
273 | return -EINVAL; |
274 | ||
aa2c96d6 | 275 | spin_lock_irqsave(&count_lock, flags); |
0347af4e | 276 | count = cpoint_count; |
aa2c96d6 | 277 | spin_unlock_irqrestore(&count_lock, flags); |
0347af4e SK |
278 | |
279 | /* No special parameters */ | |
280 | if (!cpoint_type && !cpoint_name) | |
281 | return 0; | |
282 | ||
283 | /* Neither or both of these need to be set */ | |
284 | if (!cpoint_type || !cpoint_name) | |
285 | return -EINVAL; | |
286 | ||
287 | cptype = parse_cp_type(cpoint_type, strlen(cpoint_type)); | |
93e2f585 | 288 | if (cptype == CT_NONE) |
0347af4e SK |
289 | return -EINVAL; |
290 | ||
291 | for (i = 0; i < ARRAY_SIZE(cp_name); i++) { | |
8bb31b9d AG |
292 | if (!strcmp(cpoint_name, cp_name[i])) { |
293 | cpoint = i + 1; | |
0347af4e | 294 | return 0; |
8bb31b9d AG |
295 | } |
296 | } | |
297 | ||
0347af4e SK |
298 | /* Could not find a valid crash point */ |
299 | return -EINVAL; | |
8bb31b9d AG |
300 | } |
301 | ||
7d196ac3 | 302 | static int recursive_loop(int remaining) |
8bb31b9d | 303 | { |
7d196ac3 | 304 | char buf[REC_STACK_SIZE]; |
8bb31b9d | 305 | |
7d196ac3 KC |
306 | /* Make sure compiler does not optimize this away. */ |
307 | memset(buf, (remaining & 0xff) | 0x1, REC_STACK_SIZE); | |
308 | if (!remaining) | |
8bb31b9d AG |
309 | return 0; |
310 | else | |
7d196ac3 | 311 | return recursive_loop(remaining - 1); |
8bb31b9d AG |
312 | } |
313 | ||
cc33c537 KC |
314 | static void do_nothing(void) |
315 | { | |
316 | return; | |
317 | } | |
318 | ||
629c66a2 KC |
319 | static noinline void corrupt_stack(void) |
320 | { | |
321 | /* Use default char array length that triggers stack protection. */ | |
322 | char data[8]; | |
323 | ||
324 | memset((void *)data, 0, 64); | |
325 | } | |
326 | ||
cc33c537 KC |
327 | static void execute_location(void *dst) |
328 | { | |
329 | void (*func)(void) = dst; | |
330 | ||
331 | memcpy(dst, do_nothing, EXEC_SIZE); | |
332 | func(); | |
333 | } | |
334 | ||
9ae113ce KC |
335 | static void execute_user_location(void *dst) |
336 | { | |
5123662a | 337 | /* Intentionally crossing kernel/user memory boundary. */ |
9ae113ce KC |
338 | void (*func)(void) = dst; |
339 | ||
5123662a | 340 | if (copy_to_user((void __user *)dst, do_nothing, EXEC_SIZE)) |
9ae113ce KC |
341 | return; |
342 | func(); | |
343 | } | |
344 | ||
0347af4e | 345 | static void lkdtm_do_action(enum ctype which) |
8bb31b9d | 346 | { |
0347af4e | 347 | switch (which) { |
93e2f585 | 348 | case CT_PANIC: |
0347af4e SK |
349 | panic("dumptest"); |
350 | break; | |
93e2f585 | 351 | case CT_BUG: |
0347af4e SK |
352 | BUG(); |
353 | break; | |
65892723 KC |
354 | case CT_WARNING: |
355 | WARN_ON(1); | |
356 | break; | |
93e2f585 | 357 | case CT_EXCEPTION: |
0347af4e SK |
358 | *((int *) 0) = 0; |
359 | break; | |
93e2f585 | 360 | case CT_LOOP: |
0347af4e SK |
361 | for (;;) |
362 | ; | |
363 | break; | |
93e2f585 | 364 | case CT_OVERFLOW: |
7d196ac3 | 365 | (void) recursive_loop(recur_count); |
0347af4e | 366 | break; |
629c66a2 KC |
367 | case CT_CORRUPT_STACK: |
368 | corrupt_stack(); | |
0347af4e | 369 | break; |
93e2f585 | 370 | case CT_UNALIGNED_LOAD_STORE_WRITE: { |
0347af4e SK |
371 | static u8 data[5] __attribute__((aligned(4))) = {1, 2, |
372 | 3, 4, 5}; | |
373 | u32 *p; | |
374 | u32 val = 0x12345678; | |
375 | ||
376 | p = (u32 *)(data + 1); | |
377 | if (*p == 0) | |
378 | val = 0x87654321; | |
379 | *p = val; | |
380 | break; | |
381 | } | |
93e2f585 | 382 | case CT_OVERWRITE_ALLOCATION: { |
0347af4e SK |
383 | size_t len = 1020; |
384 | u32 *data = kmalloc(len, GFP_KERNEL); | |
385 | ||
386 | data[1024 / sizeof(u32)] = 0x12345678; | |
387 | kfree(data); | |
388 | break; | |
389 | } | |
93e2f585 | 390 | case CT_WRITE_AFTER_FREE: { |
0347af4e SK |
391 | size_t len = 1024; |
392 | u32 *data = kmalloc(len, GFP_KERNEL); | |
393 | ||
394 | kfree(data); | |
395 | schedule(); | |
396 | memset(data, 0x78, len); | |
397 | break; | |
398 | } | |
93e2f585 | 399 | case CT_SOFTLOCKUP: |
a48223f9 FW |
400 | preempt_disable(); |
401 | for (;;) | |
402 | cpu_relax(); | |
403 | break; | |
93e2f585 | 404 | case CT_HARDLOCKUP: |
a48223f9 FW |
405 | local_irq_disable(); |
406 | for (;;) | |
407 | cpu_relax(); | |
408 | break; | |
274a5855 KC |
409 | case CT_SPINLOCKUP: |
410 | /* Must be called twice to trigger. */ | |
411 | spin_lock(&lock_me_up); | |
5123662a KC |
412 | /* Let sparse know we intended to exit holding the lock. */ |
413 | __release(&lock_me_up); | |
274a5855 | 414 | break; |
93e2f585 | 415 | case CT_HUNG_TASK: |
a48223f9 FW |
416 | set_current_state(TASK_UNINTERRUPTIBLE); |
417 | schedule(); | |
418 | break; | |
cc33c537 KC |
419 | case CT_EXEC_DATA: |
420 | execute_location(data_area); | |
421 | break; | |
422 | case CT_EXEC_STACK: { | |
423 | u8 stack_area[EXEC_SIZE]; | |
424 | execute_location(stack_area); | |
425 | break; | |
426 | } | |
427 | case CT_EXEC_KMALLOC: { | |
428 | u32 *kmalloc_area = kmalloc(EXEC_SIZE, GFP_KERNEL); | |
429 | execute_location(kmalloc_area); | |
430 | kfree(kmalloc_area); | |
431 | break; | |
432 | } | |
433 | case CT_EXEC_VMALLOC: { | |
434 | u32 *vmalloc_area = vmalloc(EXEC_SIZE); | |
435 | execute_location(vmalloc_area); | |
436 | vfree(vmalloc_area); | |
437 | break; | |
438 | } | |
9ae113ce KC |
439 | case CT_EXEC_USERSPACE: { |
440 | unsigned long user_addr; | |
441 | ||
442 | user_addr = vm_mmap(NULL, 0, PAGE_SIZE, | |
443 | PROT_READ | PROT_WRITE | PROT_EXEC, | |
444 | MAP_ANONYMOUS | MAP_PRIVATE, 0); | |
445 | if (user_addr >= TASK_SIZE) { | |
446 | pr_warn("Failed to allocate user memory\n"); | |
447 | return; | |
448 | } | |
449 | execute_user_location((void *)user_addr); | |
450 | vm_munmap(user_addr, PAGE_SIZE); | |
451 | break; | |
452 | } | |
453 | case CT_ACCESS_USERSPACE: { | |
454 | unsigned long user_addr, tmp; | |
455 | unsigned long *ptr; | |
456 | ||
457 | user_addr = vm_mmap(NULL, 0, PAGE_SIZE, | |
458 | PROT_READ | PROT_WRITE | PROT_EXEC, | |
459 | MAP_ANONYMOUS | MAP_PRIVATE, 0); | |
460 | if (user_addr >= TASK_SIZE) { | |
461 | pr_warn("Failed to allocate user memory\n"); | |
462 | return; | |
463 | } | |
464 | ||
465 | ptr = (unsigned long *)user_addr; | |
466 | tmp = *ptr; | |
467 | tmp += 0xc0dec0de; | |
468 | *ptr = tmp; | |
469 | ||
470 | vm_munmap(user_addr, PAGE_SIZE); | |
471 | ||
472 | break; | |
473 | } | |
474 | case CT_WRITE_RO: { | |
475 | unsigned long *ptr; | |
476 | ||
477 | ptr = (unsigned long *)&rodata; | |
478 | *ptr ^= 0xabcd1234; | |
479 | ||
480 | break; | |
481 | } | |
93e2f585 | 482 | case CT_NONE: |
0347af4e SK |
483 | default: |
484 | break; | |
485 | } | |
486 | ||
487 | } | |
488 | ||
489 | static void lkdtm_handler(void) | |
490 | { | |
aa2c96d6 | 491 | unsigned long flags; |
92618184 | 492 | bool do_it = false; |
aa2c96d6 JH |
493 | |
494 | spin_lock_irqsave(&count_lock, flags); | |
0347af4e SK |
495 | count--; |
496 | printk(KERN_INFO "lkdtm: Crash point %s of type %s hit, trigger in %d rounds\n", | |
497 | cp_name_to_str(cpoint), cp_type_to_str(cptype), count); | |
8bb31b9d AG |
498 | |
499 | if (count == 0) { | |
92618184 | 500 | do_it = true; |
8bb31b9d AG |
501 | count = cpoint_count; |
502 | } | |
aa2c96d6 | 503 | spin_unlock_irqrestore(&count_lock, flags); |
92618184 CW |
504 | |
505 | if (do_it) | |
506 | lkdtm_do_action(cptype); | |
8bb31b9d AG |
507 | } |
508 | ||
0347af4e | 509 | static int lkdtm_register_cpoint(enum cname which) |
8bb31b9d AG |
510 | { |
511 | int ret; | |
512 | ||
93e2f585 | 513 | cpoint = CN_INVALID; |
0347af4e SK |
514 | if (lkdtm.entry != NULL) |
515 | unregister_jprobe(&lkdtm); | |
8bb31b9d | 516 | |
0347af4e | 517 | switch (which) { |
93e2f585 | 518 | case CN_DIRECT: |
0347af4e SK |
519 | lkdtm_do_action(cptype); |
520 | return 0; | |
93e2f585 | 521 | case CN_INT_HARDWARE_ENTRY: |
f58f2fa9 | 522 | lkdtm.kp.symbol_name = "do_IRQ"; |
8bb31b9d AG |
523 | lkdtm.entry = (kprobe_opcode_t*) jp_do_irq; |
524 | break; | |
93e2f585 | 525 | case CN_INT_HW_IRQ_EN: |
8bb31b9d AG |
526 | lkdtm.kp.symbol_name = "handle_IRQ_event"; |
527 | lkdtm.entry = (kprobe_opcode_t*) jp_handle_irq_event; | |
528 | break; | |
93e2f585 | 529 | case CN_INT_TASKLET_ENTRY: |
8bb31b9d AG |
530 | lkdtm.kp.symbol_name = "tasklet_action"; |
531 | lkdtm.entry = (kprobe_opcode_t*) jp_tasklet_action; | |
532 | break; | |
93e2f585 | 533 | case CN_FS_DEVRW: |
8bb31b9d AG |
534 | lkdtm.kp.symbol_name = "ll_rw_block"; |
535 | lkdtm.entry = (kprobe_opcode_t*) jp_ll_rw_block; | |
536 | break; | |
93e2f585 | 537 | case CN_MEM_SWAPOUT: |
18a61e4a AG |
538 | lkdtm.kp.symbol_name = "shrink_inactive_list"; |
539 | lkdtm.entry = (kprobe_opcode_t*) jp_shrink_inactive_list; | |
8bb31b9d | 540 | break; |
93e2f585 | 541 | case CN_TIMERADD: |
8bb31b9d AG |
542 | lkdtm.kp.symbol_name = "hrtimer_start"; |
543 | lkdtm.entry = (kprobe_opcode_t*) jp_hrtimer_start; | |
544 | break; | |
93e2f585 | 545 | case CN_SCSI_DISPATCH_CMD: |
8bb31b9d AG |
546 | lkdtm.kp.symbol_name = "scsi_dispatch_cmd"; |
547 | lkdtm.entry = (kprobe_opcode_t*) jp_scsi_dispatch_cmd; | |
548 | break; | |
93e2f585 | 549 | case CN_IDE_CORE_CP: |
8bb31b9d AG |
550 | #ifdef CONFIG_IDE |
551 | lkdtm.kp.symbol_name = "generic_ide_ioctl"; | |
552 | lkdtm.entry = (kprobe_opcode_t*) jp_generic_ide_ioctl; | |
553 | #else | |
0347af4e SK |
554 | printk(KERN_INFO "lkdtm: Crash point not available\n"); |
555 | return -EINVAL; | |
8bb31b9d AG |
556 | #endif |
557 | break; | |
558 | default: | |
0347af4e SK |
559 | printk(KERN_INFO "lkdtm: Invalid Crash Point\n"); |
560 | return -EINVAL; | |
8bb31b9d AG |
561 | } |
562 | ||
0347af4e | 563 | cpoint = which; |
8bb31b9d | 564 | if ((ret = register_jprobe(&lkdtm)) < 0) { |
0347af4e | 565 | printk(KERN_INFO "lkdtm: Couldn't register jprobe\n"); |
93e2f585 | 566 | cpoint = CN_INVALID; |
0347af4e SK |
567 | } |
568 | ||
569 | return ret; | |
570 | } | |
571 | ||
572 | static ssize_t do_register_entry(enum cname which, struct file *f, | |
573 | const char __user *user_buf, size_t count, loff_t *off) | |
574 | { | |
575 | char *buf; | |
576 | int err; | |
577 | ||
578 | if (count >= PAGE_SIZE) | |
579 | return -EINVAL; | |
580 | ||
581 | buf = (char *)__get_free_page(GFP_KERNEL); | |
582 | if (!buf) | |
583 | return -ENOMEM; | |
584 | if (copy_from_user(buf, user_buf, count)) { | |
585 | free_page((unsigned long) buf); | |
586 | return -EFAULT; | |
587 | } | |
588 | /* NULL-terminate and remove enter */ | |
589 | buf[count] = '\0'; | |
590 | strim(buf); | |
591 | ||
592 | cptype = parse_cp_type(buf, count); | |
593 | free_page((unsigned long) buf); | |
594 | ||
93e2f585 | 595 | if (cptype == CT_NONE) |
0347af4e SK |
596 | return -EINVAL; |
597 | ||
598 | err = lkdtm_register_cpoint(which); | |
599 | if (err < 0) | |
600 | return err; | |
601 | ||
602 | *off += count; | |
603 | ||
604 | return count; | |
605 | } | |
606 | ||
607 | /* Generic read callback that just prints out the available crash types */ | |
608 | static ssize_t lkdtm_debugfs_read(struct file *f, char __user *user_buf, | |
609 | size_t count, loff_t *off) | |
610 | { | |
611 | char *buf; | |
612 | int i, n, out; | |
613 | ||
614 | buf = (char *)__get_free_page(GFP_KERNEL); | |
086ff4b3 AC |
615 | if (buf == NULL) |
616 | return -ENOMEM; | |
0347af4e SK |
617 | |
618 | n = snprintf(buf, PAGE_SIZE, "Available crash types:\n"); | |
619 | for (i = 0; i < ARRAY_SIZE(cp_type); i++) | |
620 | n += snprintf(buf + n, PAGE_SIZE - n, "%s\n", cp_type[i]); | |
621 | buf[n] = '\0'; | |
622 | ||
623 | out = simple_read_from_buffer(user_buf, count, off, | |
624 | buf, n); | |
625 | free_page((unsigned long) buf); | |
626 | ||
627 | return out; | |
628 | } | |
629 | ||
630 | static int lkdtm_debugfs_open(struct inode *inode, struct file *file) | |
631 | { | |
632 | return 0; | |
633 | } | |
634 | ||
635 | ||
636 | static ssize_t int_hardware_entry(struct file *f, const char __user *buf, | |
637 | size_t count, loff_t *off) | |
638 | { | |
93e2f585 | 639 | return do_register_entry(CN_INT_HARDWARE_ENTRY, f, buf, count, off); |
0347af4e SK |
640 | } |
641 | ||
642 | static ssize_t int_hw_irq_en(struct file *f, const char __user *buf, | |
643 | size_t count, loff_t *off) | |
644 | { | |
93e2f585 | 645 | return do_register_entry(CN_INT_HW_IRQ_EN, f, buf, count, off); |
0347af4e SK |
646 | } |
647 | ||
648 | static ssize_t int_tasklet_entry(struct file *f, const char __user *buf, | |
649 | size_t count, loff_t *off) | |
650 | { | |
93e2f585 | 651 | return do_register_entry(CN_INT_TASKLET_ENTRY, f, buf, count, off); |
0347af4e SK |
652 | } |
653 | ||
654 | static ssize_t fs_devrw_entry(struct file *f, const char __user *buf, | |
655 | size_t count, loff_t *off) | |
656 | { | |
93e2f585 | 657 | return do_register_entry(CN_FS_DEVRW, f, buf, count, off); |
0347af4e SK |
658 | } |
659 | ||
660 | static ssize_t mem_swapout_entry(struct file *f, const char __user *buf, | |
661 | size_t count, loff_t *off) | |
662 | { | |
93e2f585 | 663 | return do_register_entry(CN_MEM_SWAPOUT, f, buf, count, off); |
0347af4e SK |
664 | } |
665 | ||
666 | static ssize_t timeradd_entry(struct file *f, const char __user *buf, | |
667 | size_t count, loff_t *off) | |
668 | { | |
93e2f585 | 669 | return do_register_entry(CN_TIMERADD, f, buf, count, off); |
0347af4e SK |
670 | } |
671 | ||
672 | static ssize_t scsi_dispatch_cmd_entry(struct file *f, | |
673 | const char __user *buf, size_t count, loff_t *off) | |
674 | { | |
93e2f585 | 675 | return do_register_entry(CN_SCSI_DISPATCH_CMD, f, buf, count, off); |
0347af4e SK |
676 | } |
677 | ||
678 | static ssize_t ide_core_cp_entry(struct file *f, const char __user *buf, | |
679 | size_t count, loff_t *off) | |
680 | { | |
93e2f585 | 681 | return do_register_entry(CN_IDE_CORE_CP, f, buf, count, off); |
0347af4e SK |
682 | } |
683 | ||
684 | /* Special entry to just crash directly. Available without KPROBEs */ | |
685 | static ssize_t direct_entry(struct file *f, const char __user *user_buf, | |
686 | size_t count, loff_t *off) | |
687 | { | |
688 | enum ctype type; | |
689 | char *buf; | |
690 | ||
691 | if (count >= PAGE_SIZE) | |
692 | return -EINVAL; | |
693 | if (count < 1) | |
694 | return -EINVAL; | |
695 | ||
696 | buf = (char *)__get_free_page(GFP_KERNEL); | |
697 | if (!buf) | |
698 | return -ENOMEM; | |
699 | if (copy_from_user(buf, user_buf, count)) { | |
700 | free_page((unsigned long) buf); | |
701 | return -EFAULT; | |
702 | } | |
703 | /* NULL-terminate and remove enter */ | |
704 | buf[count] = '\0'; | |
705 | strim(buf); | |
706 | ||
707 | type = parse_cp_type(buf, count); | |
708 | free_page((unsigned long) buf); | |
93e2f585 | 709 | if (type == CT_NONE) |
0347af4e SK |
710 | return -EINVAL; |
711 | ||
712 | printk(KERN_INFO "lkdtm: Performing direct entry %s\n", | |
713 | cp_type_to_str(type)); | |
714 | lkdtm_do_action(type); | |
715 | *off += count; | |
716 | ||
717 | return count; | |
718 | } | |
719 | ||
720 | struct crash_entry { | |
721 | const char *name; | |
722 | const struct file_operations fops; | |
723 | }; | |
724 | ||
725 | static const struct crash_entry crash_entries[] = { | |
726 | {"DIRECT", {.read = lkdtm_debugfs_read, | |
05271ec4 | 727 | .llseek = generic_file_llseek, |
0347af4e SK |
728 | .open = lkdtm_debugfs_open, |
729 | .write = direct_entry} }, | |
730 | {"INT_HARDWARE_ENTRY", {.read = lkdtm_debugfs_read, | |
05271ec4 | 731 | .llseek = generic_file_llseek, |
0347af4e SK |
732 | .open = lkdtm_debugfs_open, |
733 | .write = int_hardware_entry} }, | |
734 | {"INT_HW_IRQ_EN", {.read = lkdtm_debugfs_read, | |
05271ec4 | 735 | .llseek = generic_file_llseek, |
0347af4e SK |
736 | .open = lkdtm_debugfs_open, |
737 | .write = int_hw_irq_en} }, | |
738 | {"INT_TASKLET_ENTRY", {.read = lkdtm_debugfs_read, | |
05271ec4 | 739 | .llseek = generic_file_llseek, |
0347af4e SK |
740 | .open = lkdtm_debugfs_open, |
741 | .write = int_tasklet_entry} }, | |
742 | {"FS_DEVRW", {.read = lkdtm_debugfs_read, | |
05271ec4 | 743 | .llseek = generic_file_llseek, |
0347af4e SK |
744 | .open = lkdtm_debugfs_open, |
745 | .write = fs_devrw_entry} }, | |
746 | {"MEM_SWAPOUT", {.read = lkdtm_debugfs_read, | |
05271ec4 | 747 | .llseek = generic_file_llseek, |
0347af4e SK |
748 | .open = lkdtm_debugfs_open, |
749 | .write = mem_swapout_entry} }, | |
750 | {"TIMERADD", {.read = lkdtm_debugfs_read, | |
05271ec4 | 751 | .llseek = generic_file_llseek, |
0347af4e SK |
752 | .open = lkdtm_debugfs_open, |
753 | .write = timeradd_entry} }, | |
754 | {"SCSI_DISPATCH_CMD", {.read = lkdtm_debugfs_read, | |
05271ec4 | 755 | .llseek = generic_file_llseek, |
0347af4e SK |
756 | .open = lkdtm_debugfs_open, |
757 | .write = scsi_dispatch_cmd_entry} }, | |
758 | {"IDE_CORE_CP", {.read = lkdtm_debugfs_read, | |
05271ec4 | 759 | .llseek = generic_file_llseek, |
0347af4e SK |
760 | .open = lkdtm_debugfs_open, |
761 | .write = ide_core_cp_entry} }, | |
762 | }; | |
763 | ||
764 | static struct dentry *lkdtm_debugfs_root; | |
765 | ||
766 | static int __init lkdtm_module_init(void) | |
767 | { | |
768 | int ret = -EINVAL; | |
769 | int n_debugfs_entries = 1; /* Assume only the direct entry */ | |
770 | int i; | |
771 | ||
772 | /* Register debugfs interface */ | |
773 | lkdtm_debugfs_root = debugfs_create_dir("provoke-crash", NULL); | |
774 | if (!lkdtm_debugfs_root) { | |
775 | printk(KERN_ERR "lkdtm: creating root dir failed\n"); | |
776 | return -ENODEV; | |
777 | } | |
778 | ||
779 | #ifdef CONFIG_KPROBES | |
780 | n_debugfs_entries = ARRAY_SIZE(crash_entries); | |
781 | #endif | |
782 | ||
783 | for (i = 0; i < n_debugfs_entries; i++) { | |
784 | const struct crash_entry *cur = &crash_entries[i]; | |
785 | struct dentry *de; | |
786 | ||
787 | de = debugfs_create_file(cur->name, 0644, lkdtm_debugfs_root, | |
788 | NULL, &cur->fops); | |
789 | if (de == NULL) { | |
790 | printk(KERN_ERR "lkdtm: could not create %s\n", | |
791 | cur->name); | |
792 | goto out_err; | |
793 | } | |
794 | } | |
795 | ||
796 | if (lkdtm_parse_commandline() == -EINVAL) { | |
797 | printk(KERN_INFO "lkdtm: Invalid command\n"); | |
798 | goto out_err; | |
799 | } | |
800 | ||
93e2f585 | 801 | if (cpoint != CN_INVALID && cptype != CT_NONE) { |
0347af4e SK |
802 | ret = lkdtm_register_cpoint(cpoint); |
803 | if (ret < 0) { | |
804 | printk(KERN_INFO "lkdtm: Invalid crash point %d\n", | |
805 | cpoint); | |
806 | goto out_err; | |
807 | } | |
808 | printk(KERN_INFO "lkdtm: Crash point %s of type %s registered\n", | |
809 | cpoint_name, cpoint_type); | |
810 | } else { | |
811 | printk(KERN_INFO "lkdtm: No crash points registered, enable through debugfs\n"); | |
8bb31b9d AG |
812 | } |
813 | ||
8bb31b9d | 814 | return 0; |
0347af4e SK |
815 | |
816 | out_err: | |
817 | debugfs_remove_recursive(lkdtm_debugfs_root); | |
818 | return ret; | |
8bb31b9d AG |
819 | } |
820 | ||
2118116e | 821 | static void __exit lkdtm_module_exit(void) |
8bb31b9d | 822 | { |
0347af4e SK |
823 | debugfs_remove_recursive(lkdtm_debugfs_root); |
824 | ||
825 | unregister_jprobe(&lkdtm); | |
826 | printk(KERN_INFO "lkdtm: Crash point unregistered\n"); | |
8bb31b9d AG |
827 | } |
828 | ||
829 | module_init(lkdtm_module_init); | |
830 | module_exit(lkdtm_module_exit); | |
831 | ||
832 | MODULE_LICENSE("GPL"); |