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 | 32 | */ |
feac6e21 | 33 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
8bb31b9d AG |
34 | |
35 | #include <linux/kernel.h> | |
5d861d92 | 36 | #include <linux/fs.h> |
8bb31b9d | 37 | #include <linux/module.h> |
5d861d92 | 38 | #include <linux/buffer_head.h> |
8bb31b9d | 39 | #include <linux/kprobes.h> |
5d861d92 | 40 | #include <linux/list.h> |
8bb31b9d | 41 | #include <linux/init.h> |
8bb31b9d | 42 | #include <linux/interrupt.h> |
5d861d92 | 43 | #include <linux/hrtimer.h> |
5a0e3ad6 | 44 | #include <linux/slab.h> |
8bb31b9d | 45 | #include <scsi/scsi_cmnd.h> |
0347af4e | 46 | #include <linux/debugfs.h> |
cc33c537 | 47 | #include <linux/vmalloc.h> |
9ae113ce | 48 | #include <linux/mman.h> |
1bc9fac3 | 49 | #include <asm/cacheflush.h> |
8bb31b9d AG |
50 | |
51 | #ifdef CONFIG_IDE | |
52 | #include <linux/ide.h> | |
53 | #endif | |
54 | ||
7d196ac3 KC |
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 | ||
8bb31b9d | 67 | #define DEFAULT_COUNT 10 |
cc33c537 | 68 | #define EXEC_SIZE 64 |
8bb31b9d AG |
69 | |
70 | enum cname { | |
93e2f585 NK |
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, | |
8bb31b9d AG |
81 | }; |
82 | ||
83 | enum ctype { | |
93e2f585 NK |
84 | CT_NONE, |
85 | CT_PANIC, | |
86 | CT_BUG, | |
65892723 | 87 | CT_WARNING, |
93e2f585 NK |
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, | |
274a5855 | 97 | CT_SPINLOCKUP, |
93e2f585 | 98 | CT_HUNG_TASK, |
cc33c537 KC |
99 | CT_EXEC_DATA, |
100 | CT_EXEC_STACK, | |
101 | CT_EXEC_KMALLOC, | |
102 | CT_EXEC_VMALLOC, | |
9ae113ce KC |
103 | CT_EXEC_USERSPACE, |
104 | CT_ACCESS_USERSPACE, | |
105 | CT_WRITE_RO, | |
dc2b9e90 | 106 | CT_WRITE_KERN, |
8bb31b9d AG |
107 | }; |
108 | ||
109 | static 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", | |
0347af4e SK |
117 | "IDE_CORE_CP", |
118 | "DIRECT", | |
8bb31b9d AG |
119 | }; |
120 | ||
121 | static char* cp_type[] = { | |
122 | "PANIC", | |
123 | "BUG", | |
65892723 | 124 | "WARNING", |
8bb31b9d AG |
125 | "EXCEPTION", |
126 | "LOOP", | |
0347af4e SK |
127 | "OVERFLOW", |
128 | "CORRUPT_STACK", | |
129 | "UNALIGNED_LOAD_STORE_WRITE", | |
130 | "OVERWRITE_ALLOCATION", | |
131 | "WRITE_AFTER_FREE", | |
a48223f9 FW |
132 | "SOFTLOCKUP", |
133 | "HARDLOCKUP", | |
274a5855 | 134 | "SPINLOCKUP", |
a48223f9 | 135 | "HUNG_TASK", |
cc33c537 KC |
136 | "EXEC_DATA", |
137 | "EXEC_STACK", | |
138 | "EXEC_KMALLOC", | |
139 | "EXEC_VMALLOC", | |
9ae113ce KC |
140 | "EXEC_USERSPACE", |
141 | "ACCESS_USERSPACE", | |
142 | "WRITE_RO", | |
dc2b9e90 | 143 | "WRITE_KERN", |
8bb31b9d AG |
144 | }; |
145 | ||
146 | static struct jprobe lkdtm; | |
147 | ||
148 | static int lkdtm_parse_commandline(void); | |
149 | static void lkdtm_handler(void); | |
150 | ||
ec1c620b AV |
151 | static char* cpoint_name; |
152 | static char* cpoint_type; | |
8bb31b9d AG |
153 | static int cpoint_count = DEFAULT_COUNT; |
154 | static int recur_count = REC_NUM_DEFAULT; | |
155 | ||
93e2f585 NK |
156 | static enum cname cpoint = CN_INVALID; |
157 | static enum ctype cptype = CT_NONE; | |
8bb31b9d | 158 | static int count = DEFAULT_COUNT; |
aa2c96d6 | 159 | static DEFINE_SPINLOCK(count_lock); |
274a5855 | 160 | static DEFINE_SPINLOCK(lock_me_up); |
8bb31b9d | 161 | |
cc33c537 KC |
162 | static u8 data_area[EXEC_SIZE]; |
163 | ||
9ae113ce KC |
164 | static const unsigned long rodata = 0xAA55AA55; |
165 | ||
8bb31b9d | 166 | module_param(recur_count, int, 0644); |
7d196ac3 | 167 | MODULE_PARM_DESC(recur_count, " Recursion level for the stack overflow test"); |
dca41306 | 168 | module_param(cpoint_name, charp, 0444); |
5d861d92 | 169 | MODULE_PARM_DESC(cpoint_name, " Crash Point, where kernel is to be crashed"); |
dca41306 | 170 | module_param(cpoint_type, charp, 0444); |
5d861d92 RD |
171 | MODULE_PARM_DESC(cpoint_type, " Crash Point Type, action to be taken on "\ |
172 | "hitting the crash point"); | |
173 | module_param(cpoint_count, int, 0644); | |
174 | MODULE_PARM_DESC(cpoint_count, " Crash Point Count, number of times the "\ | |
175 | "crash point is to be hit to trigger action"); | |
8bb31b9d | 176 | |
2118116e | 177 | static unsigned int jp_do_irq(unsigned int irq) |
8bb31b9d AG |
178 | { |
179 | lkdtm_handler(); | |
180 | jprobe_return(); | |
181 | return 0; | |
182 | } | |
183 | ||
2118116e AB |
184 | static irqreturn_t jp_handle_irq_event(unsigned int irq, |
185 | struct irqaction *action) | |
8bb31b9d AG |
186 | { |
187 | lkdtm_handler(); | |
188 | jprobe_return(); | |
189 | return 0; | |
190 | } | |
191 | ||
2118116e | 192 | static void jp_tasklet_action(struct softirq_action *a) |
8bb31b9d AG |
193 | { |
194 | lkdtm_handler(); | |
195 | jprobe_return(); | |
196 | } | |
197 | ||
2118116e | 198 | static void jp_ll_rw_block(int rw, int nr, struct buffer_head *bhs[]) |
8bb31b9d AG |
199 | { |
200 | lkdtm_handler(); | |
201 | jprobe_return(); | |
202 | } | |
203 | ||
204 | struct scan_control; | |
205 | ||
2118116e AB |
206 | static unsigned long jp_shrink_inactive_list(unsigned long max_scan, |
207 | struct zone *zone, | |
208 | struct scan_control *sc) | |
8bb31b9d AG |
209 | { |
210 | lkdtm_handler(); | |
211 | jprobe_return(); | |
212 | return 0; | |
213 | } | |
214 | ||
2118116e AB |
215 | static int jp_hrtimer_start(struct hrtimer *timer, ktime_t tim, |
216 | const enum hrtimer_mode mode) | |
8bb31b9d AG |
217 | { |
218 | lkdtm_handler(); | |
219 | jprobe_return(); | |
220 | return 0; | |
221 | } | |
222 | ||
2118116e | 223 | static int jp_scsi_dispatch_cmd(struct scsi_cmnd *cmd) |
8bb31b9d AG |
224 | { |
225 | lkdtm_handler(); | |
226 | jprobe_return(); | |
227 | return 0; | |
228 | } | |
229 | ||
230 | #ifdef CONFIG_IDE | |
44629432 | 231 | static int jp_generic_ide_ioctl(ide_drive_t *drive, struct file *file, |
8bb31b9d AG |
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 | ||
0347af4e SK |
241 | /* Return the crashpoint number or NONE if the name is invalid */ |
242 | static 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 | ||
93e2f585 | 251 | return CT_NONE; |
0347af4e SK |
252 | } |
253 | ||
254 | static const char *cp_type_to_str(enum ctype type) | |
255 | { | |
93e2f585 | 256 | if (type == CT_NONE || type < 0 || type > ARRAY_SIZE(cp_type)) |
0347af4e SK |
257 | return "None"; |
258 | ||
259 | return cp_type[type - 1]; | |
260 | } | |
261 | ||
262 | static const char *cp_name_to_str(enum cname name) | |
263 | { | |
93e2f585 | 264 | if (name == CN_INVALID || name < 0 || name > ARRAY_SIZE(cp_name)) |
0347af4e SK |
265 | return "INVALID"; |
266 | ||
267 | return cp_name[name - 1]; | |
268 | } | |
269 | ||
270 | ||
8bb31b9d AG |
271 | static int lkdtm_parse_commandline(void) |
272 | { | |
273 | int i; | |
aa2c96d6 | 274 | unsigned long flags; |
8bb31b9d | 275 | |
0347af4e | 276 | if (cpoint_count < 1 || recur_count < 1) |
8bb31b9d AG |
277 | return -EINVAL; |
278 | ||
aa2c96d6 | 279 | spin_lock_irqsave(&count_lock, flags); |
0347af4e | 280 | count = cpoint_count; |
aa2c96d6 | 281 | spin_unlock_irqrestore(&count_lock, flags); |
0347af4e SK |
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)); | |
93e2f585 | 292 | if (cptype == CT_NONE) |
0347af4e SK |
293 | return -EINVAL; |
294 | ||
295 | for (i = 0; i < ARRAY_SIZE(cp_name); i++) { | |
8bb31b9d AG |
296 | if (!strcmp(cpoint_name, cp_name[i])) { |
297 | cpoint = i + 1; | |
0347af4e | 298 | return 0; |
8bb31b9d AG |
299 | } |
300 | } | |
301 | ||
0347af4e SK |
302 | /* Could not find a valid crash point */ |
303 | return -EINVAL; | |
8bb31b9d AG |
304 | } |
305 | ||
7d196ac3 | 306 | static int recursive_loop(int remaining) |
8bb31b9d | 307 | { |
7d196ac3 | 308 | char buf[REC_STACK_SIZE]; |
8bb31b9d | 309 | |
7d196ac3 KC |
310 | /* Make sure compiler does not optimize this away. */ |
311 | memset(buf, (remaining & 0xff) | 0x1, REC_STACK_SIZE); | |
312 | if (!remaining) | |
8bb31b9d AG |
313 | return 0; |
314 | else | |
7d196ac3 | 315 | return recursive_loop(remaining - 1); |
8bb31b9d AG |
316 | } |
317 | ||
cc33c537 KC |
318 | static void do_nothing(void) |
319 | { | |
320 | return; | |
321 | } | |
322 | ||
dc2b9e90 KC |
323 | /* Must immediately follow do_nothing for size calculuations to work out. */ |
324 | static void do_overwritten(void) | |
325 | { | |
326 | pr_info("do_overwritten wasn't overwritten!\n"); | |
327 | return; | |
328 | } | |
329 | ||
629c66a2 KC |
330 | static 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 | ||
cc33c537 KC |
338 | static void execute_location(void *dst) |
339 | { | |
340 | void (*func)(void) = dst; | |
341 | ||
aac416fc KC |
342 | pr_info("attempting ok execution at %p\n", do_nothing); |
343 | do_nothing(); | |
344 | ||
cc33c537 | 345 | memcpy(dst, do_nothing, EXEC_SIZE); |
aac416fc KC |
346 | flush_icache_range((unsigned long)dst, (unsigned long)dst + EXEC_SIZE); |
347 | pr_info("attempting bad execution at %p\n", func); | |
cc33c537 KC |
348 | func(); |
349 | } | |
350 | ||
9ae113ce KC |
351 | static void execute_user_location(void *dst) |
352 | { | |
5123662a | 353 | /* Intentionally crossing kernel/user memory boundary. */ |
9ae113ce KC |
354 | void (*func)(void) = dst; |
355 | ||
aac416fc KC |
356 | pr_info("attempting ok execution at %p\n", do_nothing); |
357 | do_nothing(); | |
358 | ||
5123662a | 359 | if (copy_to_user((void __user *)dst, do_nothing, EXEC_SIZE)) |
9ae113ce | 360 | return; |
aac416fc KC |
361 | flush_icache_range((unsigned long)dst, (unsigned long)dst + EXEC_SIZE); |
362 | pr_info("attempting bad execution at %p\n", func); | |
9ae113ce KC |
363 | func(); |
364 | } | |
365 | ||
0347af4e | 366 | static void lkdtm_do_action(enum ctype which) |
8bb31b9d | 367 | { |
0347af4e | 368 | switch (which) { |
93e2f585 | 369 | case CT_PANIC: |
0347af4e SK |
370 | panic("dumptest"); |
371 | break; | |
93e2f585 | 372 | case CT_BUG: |
0347af4e SK |
373 | BUG(); |
374 | break; | |
65892723 KC |
375 | case CT_WARNING: |
376 | WARN_ON(1); | |
377 | break; | |
93e2f585 | 378 | case CT_EXCEPTION: |
0347af4e SK |
379 | *((int *) 0) = 0; |
380 | break; | |
93e2f585 | 381 | case CT_LOOP: |
0347af4e SK |
382 | for (;;) |
383 | ; | |
384 | break; | |
93e2f585 | 385 | case CT_OVERFLOW: |
7d196ac3 | 386 | (void) recursive_loop(recur_count); |
0347af4e | 387 | break; |
629c66a2 KC |
388 | case CT_CORRUPT_STACK: |
389 | corrupt_stack(); | |
0347af4e | 390 | break; |
93e2f585 | 391 | case CT_UNALIGNED_LOAD_STORE_WRITE: { |
0347af4e SK |
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 | } | |
93e2f585 | 403 | case CT_OVERWRITE_ALLOCATION: { |
0347af4e SK |
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 | } | |
93e2f585 | 411 | case CT_WRITE_AFTER_FREE: { |
0347af4e SK |
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 | } | |
93e2f585 | 420 | case CT_SOFTLOCKUP: |
a48223f9 FW |
421 | preempt_disable(); |
422 | for (;;) | |
423 | cpu_relax(); | |
424 | break; | |
93e2f585 | 425 | case CT_HARDLOCKUP: |
a48223f9 FW |
426 | local_irq_disable(); |
427 | for (;;) | |
428 | cpu_relax(); | |
429 | break; | |
274a5855 KC |
430 | case CT_SPINLOCKUP: |
431 | /* Must be called twice to trigger. */ | |
432 | spin_lock(&lock_me_up); | |
5123662a KC |
433 | /* Let sparse know we intended to exit holding the lock. */ |
434 | __release(&lock_me_up); | |
274a5855 | 435 | break; |
93e2f585 | 436 | case CT_HUNG_TASK: |
a48223f9 FW |
437 | set_current_state(TASK_UNINTERRUPTIBLE); |
438 | schedule(); | |
439 | break; | |
cc33c537 KC |
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 | } | |
9ae113ce KC |
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; | |
aac416fc KC |
487 | |
488 | pr_info("attempting bad read at %p\n", ptr); | |
9ae113ce KC |
489 | tmp = *ptr; |
490 | tmp += 0xc0dec0de; | |
aac416fc KC |
491 | |
492 | pr_info("attempting bad write at %p\n", ptr); | |
9ae113ce KC |
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; | |
aac416fc KC |
503 | |
504 | pr_info("attempting bad write at %p\n", ptr); | |
9ae113ce KC |
505 | *ptr ^= 0xabcd1234; |
506 | ||
507 | break; | |
508 | } | |
dc2b9e90 KC |
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 | } | |
93e2f585 | 525 | case CT_NONE: |
0347af4e SK |
526 | default: |
527 | break; | |
528 | } | |
529 | ||
530 | } | |
531 | ||
532 | static void lkdtm_handler(void) | |
533 | { | |
aa2c96d6 | 534 | unsigned long flags; |
92618184 | 535 | bool do_it = false; |
aa2c96d6 JH |
536 | |
537 | spin_lock_irqsave(&count_lock, flags); | |
0347af4e | 538 | count--; |
feac6e21 KC |
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); | |
8bb31b9d AG |
541 | |
542 | if (count == 0) { | |
92618184 | 543 | do_it = true; |
8bb31b9d AG |
544 | count = cpoint_count; |
545 | } | |
aa2c96d6 | 546 | spin_unlock_irqrestore(&count_lock, flags); |
92618184 CW |
547 | |
548 | if (do_it) | |
549 | lkdtm_do_action(cptype); | |
8bb31b9d AG |
550 | } |
551 | ||
0347af4e | 552 | static int lkdtm_register_cpoint(enum cname which) |
8bb31b9d AG |
553 | { |
554 | int ret; | |
555 | ||
93e2f585 | 556 | cpoint = CN_INVALID; |
0347af4e SK |
557 | if (lkdtm.entry != NULL) |
558 | unregister_jprobe(&lkdtm); | |
8bb31b9d | 559 | |
0347af4e | 560 | switch (which) { |
93e2f585 | 561 | case CN_DIRECT: |
0347af4e SK |
562 | lkdtm_do_action(cptype); |
563 | return 0; | |
93e2f585 | 564 | case CN_INT_HARDWARE_ENTRY: |
f58f2fa9 | 565 | lkdtm.kp.symbol_name = "do_IRQ"; |
8bb31b9d AG |
566 | lkdtm.entry = (kprobe_opcode_t*) jp_do_irq; |
567 | break; | |
93e2f585 | 568 | case CN_INT_HW_IRQ_EN: |
8bb31b9d AG |
569 | lkdtm.kp.symbol_name = "handle_IRQ_event"; |
570 | lkdtm.entry = (kprobe_opcode_t*) jp_handle_irq_event; | |
571 | break; | |
93e2f585 | 572 | case CN_INT_TASKLET_ENTRY: |
8bb31b9d AG |
573 | lkdtm.kp.symbol_name = "tasklet_action"; |
574 | lkdtm.entry = (kprobe_opcode_t*) jp_tasklet_action; | |
575 | break; | |
93e2f585 | 576 | case CN_FS_DEVRW: |
8bb31b9d AG |
577 | lkdtm.kp.symbol_name = "ll_rw_block"; |
578 | lkdtm.entry = (kprobe_opcode_t*) jp_ll_rw_block; | |
579 | break; | |
93e2f585 | 580 | case CN_MEM_SWAPOUT: |
18a61e4a AG |
581 | lkdtm.kp.symbol_name = "shrink_inactive_list"; |
582 | lkdtm.entry = (kprobe_opcode_t*) jp_shrink_inactive_list; | |
8bb31b9d | 583 | break; |
93e2f585 | 584 | case CN_TIMERADD: |
8bb31b9d AG |
585 | lkdtm.kp.symbol_name = "hrtimer_start"; |
586 | lkdtm.entry = (kprobe_opcode_t*) jp_hrtimer_start; | |
587 | break; | |
93e2f585 | 588 | case CN_SCSI_DISPATCH_CMD: |
8bb31b9d AG |
589 | lkdtm.kp.symbol_name = "scsi_dispatch_cmd"; |
590 | lkdtm.entry = (kprobe_opcode_t*) jp_scsi_dispatch_cmd; | |
591 | break; | |
93e2f585 | 592 | case CN_IDE_CORE_CP: |
8bb31b9d AG |
593 | #ifdef CONFIG_IDE |
594 | lkdtm.kp.symbol_name = "generic_ide_ioctl"; | |
595 | lkdtm.entry = (kprobe_opcode_t*) jp_generic_ide_ioctl; | |
596 | #else | |
feac6e21 | 597 | pr_info("Crash point not available\n"); |
0347af4e | 598 | return -EINVAL; |
8bb31b9d AG |
599 | #endif |
600 | break; | |
601 | default: | |
feac6e21 | 602 | pr_info("Invalid Crash Point\n"); |
0347af4e | 603 | return -EINVAL; |
8bb31b9d AG |
604 | } |
605 | ||
0347af4e | 606 | cpoint = which; |
8bb31b9d | 607 | if ((ret = register_jprobe(&lkdtm)) < 0) { |
feac6e21 | 608 | pr_info("Couldn't register jprobe\n"); |
93e2f585 | 609 | cpoint = CN_INVALID; |
0347af4e SK |
610 | } |
611 | ||
612 | return ret; | |
613 | } | |
614 | ||
615 | static 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 | ||
93e2f585 | 638 | if (cptype == CT_NONE) |
0347af4e SK |
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 */ | |
651 | static 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); | |
086ff4b3 AC |
658 | if (buf == NULL) |
659 | return -ENOMEM; | |
0347af4e SK |
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 | ||
673 | static int lkdtm_debugfs_open(struct inode *inode, struct file *file) | |
674 | { | |
675 | return 0; | |
676 | } | |
677 | ||
678 | ||
679 | static ssize_t int_hardware_entry(struct file *f, const char __user *buf, | |
680 | size_t count, loff_t *off) | |
681 | { | |
93e2f585 | 682 | return do_register_entry(CN_INT_HARDWARE_ENTRY, f, buf, count, off); |
0347af4e SK |
683 | } |
684 | ||
685 | static ssize_t int_hw_irq_en(struct file *f, const char __user *buf, | |
686 | size_t count, loff_t *off) | |
687 | { | |
93e2f585 | 688 | return do_register_entry(CN_INT_HW_IRQ_EN, f, buf, count, off); |
0347af4e SK |
689 | } |
690 | ||
691 | static ssize_t int_tasklet_entry(struct file *f, const char __user *buf, | |
692 | size_t count, loff_t *off) | |
693 | { | |
93e2f585 | 694 | return do_register_entry(CN_INT_TASKLET_ENTRY, f, buf, count, off); |
0347af4e SK |
695 | } |
696 | ||
697 | static ssize_t fs_devrw_entry(struct file *f, const char __user *buf, | |
698 | size_t count, loff_t *off) | |
699 | { | |
93e2f585 | 700 | return do_register_entry(CN_FS_DEVRW, f, buf, count, off); |
0347af4e SK |
701 | } |
702 | ||
703 | static ssize_t mem_swapout_entry(struct file *f, const char __user *buf, | |
704 | size_t count, loff_t *off) | |
705 | { | |
93e2f585 | 706 | return do_register_entry(CN_MEM_SWAPOUT, f, buf, count, off); |
0347af4e SK |
707 | } |
708 | ||
709 | static ssize_t timeradd_entry(struct file *f, const char __user *buf, | |
710 | size_t count, loff_t *off) | |
711 | { | |
93e2f585 | 712 | return do_register_entry(CN_TIMERADD, f, buf, count, off); |
0347af4e SK |
713 | } |
714 | ||
715 | static ssize_t scsi_dispatch_cmd_entry(struct file *f, | |
716 | const char __user *buf, size_t count, loff_t *off) | |
717 | { | |
93e2f585 | 718 | return do_register_entry(CN_SCSI_DISPATCH_CMD, f, buf, count, off); |
0347af4e SK |
719 | } |
720 | ||
721 | static ssize_t ide_core_cp_entry(struct file *f, const char __user *buf, | |
722 | size_t count, loff_t *off) | |
723 | { | |
93e2f585 | 724 | return do_register_entry(CN_IDE_CORE_CP, f, buf, count, off); |
0347af4e SK |
725 | } |
726 | ||
727 | /* Special entry to just crash directly. Available without KPROBEs */ | |
728 | static 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); | |
93e2f585 | 752 | if (type == CT_NONE) |
0347af4e SK |
753 | return -EINVAL; |
754 | ||
feac6e21 | 755 | pr_info("Performing direct entry %s\n", cp_type_to_str(type)); |
0347af4e SK |
756 | lkdtm_do_action(type); |
757 | *off += count; | |
758 | ||
759 | return count; | |
760 | } | |
761 | ||
762 | struct crash_entry { | |
763 | const char *name; | |
764 | const struct file_operations fops; | |
765 | }; | |
766 | ||
767 | static const struct crash_entry crash_entries[] = { | |
768 | {"DIRECT", {.read = lkdtm_debugfs_read, | |
05271ec4 | 769 | .llseek = generic_file_llseek, |
0347af4e SK |
770 | .open = lkdtm_debugfs_open, |
771 | .write = direct_entry} }, | |
772 | {"INT_HARDWARE_ENTRY", {.read = lkdtm_debugfs_read, | |
05271ec4 | 773 | .llseek = generic_file_llseek, |
0347af4e SK |
774 | .open = lkdtm_debugfs_open, |
775 | .write = int_hardware_entry} }, | |
776 | {"INT_HW_IRQ_EN", {.read = lkdtm_debugfs_read, | |
05271ec4 | 777 | .llseek = generic_file_llseek, |
0347af4e SK |
778 | .open = lkdtm_debugfs_open, |
779 | .write = int_hw_irq_en} }, | |
780 | {"INT_TASKLET_ENTRY", {.read = lkdtm_debugfs_read, | |
05271ec4 | 781 | .llseek = generic_file_llseek, |
0347af4e SK |
782 | .open = lkdtm_debugfs_open, |
783 | .write = int_tasklet_entry} }, | |
784 | {"FS_DEVRW", {.read = lkdtm_debugfs_read, | |
05271ec4 | 785 | .llseek = generic_file_llseek, |
0347af4e SK |
786 | .open = lkdtm_debugfs_open, |
787 | .write = fs_devrw_entry} }, | |
788 | {"MEM_SWAPOUT", {.read = lkdtm_debugfs_read, | |
05271ec4 | 789 | .llseek = generic_file_llseek, |
0347af4e SK |
790 | .open = lkdtm_debugfs_open, |
791 | .write = mem_swapout_entry} }, | |
792 | {"TIMERADD", {.read = lkdtm_debugfs_read, | |
05271ec4 | 793 | .llseek = generic_file_llseek, |
0347af4e SK |
794 | .open = lkdtm_debugfs_open, |
795 | .write = timeradd_entry} }, | |
796 | {"SCSI_DISPATCH_CMD", {.read = lkdtm_debugfs_read, | |
05271ec4 | 797 | .llseek = generic_file_llseek, |
0347af4e SK |
798 | .open = lkdtm_debugfs_open, |
799 | .write = scsi_dispatch_cmd_entry} }, | |
800 | {"IDE_CORE_CP", {.read = lkdtm_debugfs_read, | |
05271ec4 | 801 | .llseek = generic_file_llseek, |
0347af4e SK |
802 | .open = lkdtm_debugfs_open, |
803 | .write = ide_core_cp_entry} }, | |
804 | }; | |
805 | ||
806 | static struct dentry *lkdtm_debugfs_root; | |
807 | ||
808 | static 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) { | |
feac6e21 | 817 | pr_err("creating root dir failed\n"); |
0347af4e SK |
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) { | |
feac6e21 | 832 | pr_err("could not create %s\n", cur->name); |
0347af4e SK |
833 | goto out_err; |
834 | } | |
835 | } | |
836 | ||
837 | if (lkdtm_parse_commandline() == -EINVAL) { | |
feac6e21 | 838 | pr_info("Invalid command\n"); |
0347af4e SK |
839 | goto out_err; |
840 | } | |
841 | ||
93e2f585 | 842 | if (cpoint != CN_INVALID && cptype != CT_NONE) { |
0347af4e SK |
843 | ret = lkdtm_register_cpoint(cpoint); |
844 | if (ret < 0) { | |
feac6e21 | 845 | pr_info("Invalid crash point %d\n", cpoint); |
0347af4e SK |
846 | goto out_err; |
847 | } | |
feac6e21 KC |
848 | pr_info("Crash point %s of type %s registered\n", |
849 | cpoint_name, cpoint_type); | |
0347af4e | 850 | } else { |
feac6e21 | 851 | pr_info("No crash points registered, enable through debugfs\n"); |
8bb31b9d AG |
852 | } |
853 | ||
8bb31b9d | 854 | return 0; |
0347af4e SK |
855 | |
856 | out_err: | |
857 | debugfs_remove_recursive(lkdtm_debugfs_root); | |
858 | return ret; | |
8bb31b9d AG |
859 | } |
860 | ||
2118116e | 861 | static void __exit lkdtm_module_exit(void) |
8bb31b9d | 862 | { |
0347af4e SK |
863 | debugfs_remove_recursive(lkdtm_debugfs_root); |
864 | ||
865 | unregister_jprobe(&lkdtm); | |
feac6e21 | 866 | pr_info("Crash point unregistered\n"); |
8bb31b9d AG |
867 | } |
868 | ||
869 | module_init(lkdtm_module_init); | |
870 | module_exit(lkdtm_module_exit); | |
871 | ||
872 | MODULE_LICENSE("GPL"); | |
da86920f | 873 | MODULE_DESCRIPTION("Kprobe module for testing crash dumps"); |