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, | |
bc0b8cc6 | 95 | CT_READ_AFTER_FREE, |
920d451f LA |
96 | CT_WRITE_BUDDY_AFTER_FREE, |
97 | CT_READ_BUDDY_AFTER_FREE, | |
93e2f585 NK |
98 | CT_SOFTLOCKUP, |
99 | CT_HARDLOCKUP, | |
274a5855 | 100 | CT_SPINLOCKUP, |
93e2f585 | 101 | CT_HUNG_TASK, |
cc33c537 KC |
102 | CT_EXEC_DATA, |
103 | CT_EXEC_STACK, | |
104 | CT_EXEC_KMALLOC, | |
105 | CT_EXEC_VMALLOC, | |
9ae113ce KC |
106 | CT_EXEC_USERSPACE, |
107 | CT_ACCESS_USERSPACE, | |
108 | CT_WRITE_RO, | |
7cca071c | 109 | CT_WRITE_RO_AFTER_INIT, |
dc2b9e90 | 110 | CT_WRITE_KERN, |
5fd9e480 | 111 | CT_WRAP_ATOMIC |
8bb31b9d AG |
112 | }; |
113 | ||
114 | static char* cp_name[] = { | |
115 | "INT_HARDWARE_ENTRY", | |
116 | "INT_HW_IRQ_EN", | |
117 | "INT_TASKLET_ENTRY", | |
118 | "FS_DEVRW", | |
119 | "MEM_SWAPOUT", | |
120 | "TIMERADD", | |
121 | "SCSI_DISPATCH_CMD", | |
0347af4e SK |
122 | "IDE_CORE_CP", |
123 | "DIRECT", | |
8bb31b9d AG |
124 | }; |
125 | ||
126 | static char* cp_type[] = { | |
127 | "PANIC", | |
128 | "BUG", | |
65892723 | 129 | "WARNING", |
8bb31b9d AG |
130 | "EXCEPTION", |
131 | "LOOP", | |
0347af4e SK |
132 | "OVERFLOW", |
133 | "CORRUPT_STACK", | |
134 | "UNALIGNED_LOAD_STORE_WRITE", | |
135 | "OVERWRITE_ALLOCATION", | |
136 | "WRITE_AFTER_FREE", | |
bc0b8cc6 | 137 | "READ_AFTER_FREE", |
920d451f LA |
138 | "WRITE_BUDDY_AFTER_FREE", |
139 | "READ_BUDDY_AFTER_FREE", | |
a48223f9 FW |
140 | "SOFTLOCKUP", |
141 | "HARDLOCKUP", | |
274a5855 | 142 | "SPINLOCKUP", |
a48223f9 | 143 | "HUNG_TASK", |
cc33c537 KC |
144 | "EXEC_DATA", |
145 | "EXEC_STACK", | |
146 | "EXEC_KMALLOC", | |
147 | "EXEC_VMALLOC", | |
9ae113ce KC |
148 | "EXEC_USERSPACE", |
149 | "ACCESS_USERSPACE", | |
150 | "WRITE_RO", | |
7cca071c | 151 | "WRITE_RO_AFTER_INIT", |
dc2b9e90 | 152 | "WRITE_KERN", |
5fd9e480 | 153 | "WRAP_ATOMIC" |
8bb31b9d AG |
154 | }; |
155 | ||
156 | static struct jprobe lkdtm; | |
157 | ||
158 | static int lkdtm_parse_commandline(void); | |
159 | static void lkdtm_handler(void); | |
160 | ||
ec1c620b AV |
161 | static char* cpoint_name; |
162 | static char* cpoint_type; | |
8bb31b9d AG |
163 | static int cpoint_count = DEFAULT_COUNT; |
164 | static int recur_count = REC_NUM_DEFAULT; | |
165 | ||
93e2f585 NK |
166 | static enum cname cpoint = CN_INVALID; |
167 | static enum ctype cptype = CT_NONE; | |
8bb31b9d | 168 | static int count = DEFAULT_COUNT; |
aa2c96d6 | 169 | static DEFINE_SPINLOCK(count_lock); |
274a5855 | 170 | static DEFINE_SPINLOCK(lock_me_up); |
8bb31b9d | 171 | |
cc33c537 KC |
172 | static u8 data_area[EXEC_SIZE]; |
173 | ||
9ae113ce | 174 | static const unsigned long rodata = 0xAA55AA55; |
7cca071c | 175 | static unsigned long ro_after_init __ro_after_init = 0x55AA5500; |
9ae113ce | 176 | |
8bb31b9d | 177 | module_param(recur_count, int, 0644); |
7d196ac3 | 178 | MODULE_PARM_DESC(recur_count, " Recursion level for the stack overflow test"); |
dca41306 | 179 | module_param(cpoint_name, charp, 0444); |
5d861d92 | 180 | MODULE_PARM_DESC(cpoint_name, " Crash Point, where kernel is to be crashed"); |
dca41306 | 181 | module_param(cpoint_type, charp, 0444); |
5d861d92 RD |
182 | MODULE_PARM_DESC(cpoint_type, " Crash Point Type, action to be taken on "\ |
183 | "hitting the crash point"); | |
184 | module_param(cpoint_count, int, 0644); | |
185 | MODULE_PARM_DESC(cpoint_count, " Crash Point Count, number of times the "\ | |
186 | "crash point is to be hit to trigger action"); | |
8bb31b9d | 187 | |
2118116e | 188 | static unsigned int jp_do_irq(unsigned int irq) |
8bb31b9d AG |
189 | { |
190 | lkdtm_handler(); | |
191 | jprobe_return(); | |
192 | return 0; | |
193 | } | |
194 | ||
2118116e AB |
195 | static irqreturn_t jp_handle_irq_event(unsigned int irq, |
196 | struct irqaction *action) | |
8bb31b9d AG |
197 | { |
198 | lkdtm_handler(); | |
199 | jprobe_return(); | |
200 | return 0; | |
201 | } | |
202 | ||
2118116e | 203 | static void jp_tasklet_action(struct softirq_action *a) |
8bb31b9d AG |
204 | { |
205 | lkdtm_handler(); | |
206 | jprobe_return(); | |
207 | } | |
208 | ||
2118116e | 209 | static void jp_ll_rw_block(int rw, int nr, struct buffer_head *bhs[]) |
8bb31b9d AG |
210 | { |
211 | lkdtm_handler(); | |
212 | jprobe_return(); | |
213 | } | |
214 | ||
215 | struct scan_control; | |
216 | ||
2118116e AB |
217 | static unsigned long jp_shrink_inactive_list(unsigned long max_scan, |
218 | struct zone *zone, | |
219 | struct scan_control *sc) | |
8bb31b9d AG |
220 | { |
221 | lkdtm_handler(); | |
222 | jprobe_return(); | |
223 | return 0; | |
224 | } | |
225 | ||
2118116e AB |
226 | static int jp_hrtimer_start(struct hrtimer *timer, ktime_t tim, |
227 | const enum hrtimer_mode mode) | |
8bb31b9d AG |
228 | { |
229 | lkdtm_handler(); | |
230 | jprobe_return(); | |
231 | return 0; | |
232 | } | |
233 | ||
2118116e | 234 | static int jp_scsi_dispatch_cmd(struct scsi_cmnd *cmd) |
8bb31b9d AG |
235 | { |
236 | lkdtm_handler(); | |
237 | jprobe_return(); | |
238 | return 0; | |
239 | } | |
240 | ||
241 | #ifdef CONFIG_IDE | |
44629432 | 242 | static int jp_generic_ide_ioctl(ide_drive_t *drive, struct file *file, |
8bb31b9d AG |
243 | struct block_device *bdev, unsigned int cmd, |
244 | unsigned long arg) | |
245 | { | |
246 | lkdtm_handler(); | |
247 | jprobe_return(); | |
248 | return 0; | |
249 | } | |
250 | #endif | |
251 | ||
0347af4e SK |
252 | /* Return the crashpoint number or NONE if the name is invalid */ |
253 | static enum ctype parse_cp_type(const char *what, size_t count) | |
254 | { | |
255 | int i; | |
256 | ||
257 | for (i = 0; i < ARRAY_SIZE(cp_type); i++) { | |
258 | if (!strcmp(what, cp_type[i])) | |
259 | return i + 1; | |
260 | } | |
261 | ||
93e2f585 | 262 | return CT_NONE; |
0347af4e SK |
263 | } |
264 | ||
265 | static const char *cp_type_to_str(enum ctype type) | |
266 | { | |
93e2f585 | 267 | if (type == CT_NONE || type < 0 || type > ARRAY_SIZE(cp_type)) |
0347af4e SK |
268 | return "None"; |
269 | ||
270 | return cp_type[type - 1]; | |
271 | } | |
272 | ||
273 | static const char *cp_name_to_str(enum cname name) | |
274 | { | |
93e2f585 | 275 | if (name == CN_INVALID || name < 0 || name > ARRAY_SIZE(cp_name)) |
0347af4e SK |
276 | return "INVALID"; |
277 | ||
278 | return cp_name[name - 1]; | |
279 | } | |
280 | ||
281 | ||
8bb31b9d AG |
282 | static int lkdtm_parse_commandline(void) |
283 | { | |
284 | int i; | |
aa2c96d6 | 285 | unsigned long flags; |
8bb31b9d | 286 | |
0347af4e | 287 | if (cpoint_count < 1 || recur_count < 1) |
8bb31b9d AG |
288 | return -EINVAL; |
289 | ||
aa2c96d6 | 290 | spin_lock_irqsave(&count_lock, flags); |
0347af4e | 291 | count = cpoint_count; |
aa2c96d6 | 292 | spin_unlock_irqrestore(&count_lock, flags); |
0347af4e SK |
293 | |
294 | /* No special parameters */ | |
295 | if (!cpoint_type && !cpoint_name) | |
296 | return 0; | |
297 | ||
298 | /* Neither or both of these need to be set */ | |
299 | if (!cpoint_type || !cpoint_name) | |
300 | return -EINVAL; | |
301 | ||
302 | cptype = parse_cp_type(cpoint_type, strlen(cpoint_type)); | |
93e2f585 | 303 | if (cptype == CT_NONE) |
0347af4e SK |
304 | return -EINVAL; |
305 | ||
306 | for (i = 0; i < ARRAY_SIZE(cp_name); i++) { | |
8bb31b9d AG |
307 | if (!strcmp(cpoint_name, cp_name[i])) { |
308 | cpoint = i + 1; | |
0347af4e | 309 | return 0; |
8bb31b9d AG |
310 | } |
311 | } | |
312 | ||
0347af4e SK |
313 | /* Could not find a valid crash point */ |
314 | return -EINVAL; | |
8bb31b9d AG |
315 | } |
316 | ||
7d196ac3 | 317 | static int recursive_loop(int remaining) |
8bb31b9d | 318 | { |
7d196ac3 | 319 | char buf[REC_STACK_SIZE]; |
8bb31b9d | 320 | |
7d196ac3 KC |
321 | /* Make sure compiler does not optimize this away. */ |
322 | memset(buf, (remaining & 0xff) | 0x1, REC_STACK_SIZE); | |
323 | if (!remaining) | |
8bb31b9d AG |
324 | return 0; |
325 | else | |
7d196ac3 | 326 | return recursive_loop(remaining - 1); |
8bb31b9d AG |
327 | } |
328 | ||
cc33c537 KC |
329 | static void do_nothing(void) |
330 | { | |
331 | return; | |
332 | } | |
333 | ||
dc2b9e90 KC |
334 | /* Must immediately follow do_nothing for size calculuations to work out. */ |
335 | static void do_overwritten(void) | |
336 | { | |
337 | pr_info("do_overwritten wasn't overwritten!\n"); | |
338 | return; | |
339 | } | |
340 | ||
629c66a2 KC |
341 | static noinline void corrupt_stack(void) |
342 | { | |
343 | /* Use default char array length that triggers stack protection. */ | |
344 | char data[8]; | |
345 | ||
346 | memset((void *)data, 0, 64); | |
347 | } | |
348 | ||
ececdc02 | 349 | static void noinline execute_location(void *dst) |
cc33c537 KC |
350 | { |
351 | void (*func)(void) = dst; | |
352 | ||
aac416fc KC |
353 | pr_info("attempting ok execution at %p\n", do_nothing); |
354 | do_nothing(); | |
355 | ||
cc33c537 | 356 | memcpy(dst, do_nothing, EXEC_SIZE); |
aac416fc KC |
357 | flush_icache_range((unsigned long)dst, (unsigned long)dst + EXEC_SIZE); |
358 | pr_info("attempting bad execution at %p\n", func); | |
cc33c537 KC |
359 | func(); |
360 | } | |
361 | ||
9ae113ce KC |
362 | static void execute_user_location(void *dst) |
363 | { | |
5123662a | 364 | /* Intentionally crossing kernel/user memory boundary. */ |
9ae113ce KC |
365 | void (*func)(void) = dst; |
366 | ||
aac416fc KC |
367 | pr_info("attempting ok execution at %p\n", do_nothing); |
368 | do_nothing(); | |
369 | ||
5123662a | 370 | if (copy_to_user((void __user *)dst, do_nothing, EXEC_SIZE)) |
9ae113ce | 371 | return; |
aac416fc KC |
372 | flush_icache_range((unsigned long)dst, (unsigned long)dst + EXEC_SIZE); |
373 | pr_info("attempting bad execution at %p\n", func); | |
9ae113ce KC |
374 | func(); |
375 | } | |
376 | ||
0347af4e | 377 | static void lkdtm_do_action(enum ctype which) |
8bb31b9d | 378 | { |
0347af4e | 379 | switch (which) { |
93e2f585 | 380 | case CT_PANIC: |
0347af4e SK |
381 | panic("dumptest"); |
382 | break; | |
93e2f585 | 383 | case CT_BUG: |
0347af4e SK |
384 | BUG(); |
385 | break; | |
65892723 KC |
386 | case CT_WARNING: |
387 | WARN_ON(1); | |
388 | break; | |
93e2f585 | 389 | case CT_EXCEPTION: |
0347af4e SK |
390 | *((int *) 0) = 0; |
391 | break; | |
93e2f585 | 392 | case CT_LOOP: |
0347af4e SK |
393 | for (;;) |
394 | ; | |
395 | break; | |
93e2f585 | 396 | case CT_OVERFLOW: |
7d196ac3 | 397 | (void) recursive_loop(recur_count); |
0347af4e | 398 | break; |
629c66a2 KC |
399 | case CT_CORRUPT_STACK: |
400 | corrupt_stack(); | |
0347af4e | 401 | break; |
93e2f585 | 402 | case CT_UNALIGNED_LOAD_STORE_WRITE: { |
0347af4e SK |
403 | static u8 data[5] __attribute__((aligned(4))) = {1, 2, |
404 | 3, 4, 5}; | |
405 | u32 *p; | |
406 | u32 val = 0x12345678; | |
407 | ||
408 | p = (u32 *)(data + 1); | |
409 | if (*p == 0) | |
410 | val = 0x87654321; | |
411 | *p = val; | |
412 | break; | |
413 | } | |
93e2f585 | 414 | case CT_OVERWRITE_ALLOCATION: { |
0347af4e SK |
415 | size_t len = 1020; |
416 | u32 *data = kmalloc(len, GFP_KERNEL); | |
417 | ||
418 | data[1024 / sizeof(u32)] = 0x12345678; | |
419 | kfree(data); | |
420 | break; | |
421 | } | |
93e2f585 | 422 | case CT_WRITE_AFTER_FREE: { |
7c0ae5be | 423 | int *base, *again; |
0347af4e | 424 | size_t len = 1024; |
250a8988 LA |
425 | /* |
426 | * The slub allocator uses the first word to store the free | |
427 | * pointer in some configurations. Use the middle of the | |
428 | * allocation to avoid running into the freelist | |
429 | */ | |
430 | size_t offset = (len / sizeof(*base)) / 2; | |
0347af4e | 431 | |
250a8988 LA |
432 | base = kmalloc(len, GFP_KERNEL); |
433 | pr_info("Allocated memory %p-%p\n", base, &base[offset * 2]); | |
250a8988 LA |
434 | pr_info("Attempting bad write to freed memory at %p\n", |
435 | &base[offset]); | |
7c0ae5be | 436 | kfree(base); |
250a8988 | 437 | base[offset] = 0x0abcdef0; |
7c0ae5be KC |
438 | /* Attempt to notice the overwrite. */ |
439 | again = kmalloc(len, GFP_KERNEL); | |
440 | kfree(again); | |
441 | if (again != base) | |
442 | pr_info("Hmm, didn't get the same memory range.\n"); | |
0347af4e | 443 | |
0347af4e SK |
444 | break; |
445 | } | |
bc0b8cc6 LA |
446 | case CT_READ_AFTER_FREE: { |
447 | int *base, *val, saw; | |
448 | size_t len = 1024; | |
449 | /* | |
450 | * The slub allocator uses the first word to store the free | |
451 | * pointer in some configurations. Use the middle of the | |
452 | * allocation to avoid running into the freelist | |
453 | */ | |
454 | size_t offset = (len / sizeof(*base)) / 2; | |
455 | ||
456 | base = kmalloc(len, GFP_KERNEL); | |
457 | if (!base) | |
458 | break; | |
459 | ||
460 | val = kmalloc(len, GFP_KERNEL); | |
d2e10088 SM |
461 | if (!val) { |
462 | kfree(base); | |
bc0b8cc6 | 463 | break; |
d2e10088 | 464 | } |
bc0b8cc6 LA |
465 | |
466 | *val = 0x12345678; | |
467 | base[offset] = *val; | |
468 | pr_info("Value in memory before free: %x\n", base[offset]); | |
469 | ||
470 | kfree(base); | |
471 | ||
472 | pr_info("Attempting bad read from freed memory\n"); | |
473 | saw = base[offset]; | |
474 | if (saw != *val) { | |
475 | /* Good! Poisoning happened, so declare a win. */ | |
7c0ae5be | 476 | pr_info("Memory correctly poisoned (%x)\n", saw); |
bc0b8cc6 LA |
477 | BUG(); |
478 | } | |
479 | pr_info("Memory was not poisoned\n"); | |
480 | ||
481 | kfree(val); | |
482 | break; | |
483 | } | |
920d451f LA |
484 | case CT_WRITE_BUDDY_AFTER_FREE: { |
485 | unsigned long p = __get_free_page(GFP_KERNEL); | |
486 | if (!p) | |
487 | break; | |
488 | pr_info("Writing to the buddy page before free\n"); | |
489 | memset((void *)p, 0x3, PAGE_SIZE); | |
490 | free_page(p); | |
0347af4e | 491 | schedule(); |
920d451f LA |
492 | pr_info("Attempting bad write to the buddy page after free\n"); |
493 | memset((void *)p, 0x78, PAGE_SIZE); | |
7c0ae5be KC |
494 | /* Attempt to notice the overwrite. */ |
495 | p = __get_free_page(GFP_KERNEL); | |
496 | free_page(p); | |
0347af4e | 497 | schedule(); |
7c0ae5be | 498 | |
920d451f LA |
499 | break; |
500 | } | |
501 | case CT_READ_BUDDY_AFTER_FREE: { | |
502 | unsigned long p = __get_free_page(GFP_KERNEL); | |
50fbd977 | 503 | int saw, *val; |
920d451f LA |
504 | int *base; |
505 | ||
506 | if (!p) | |
507 | break; | |
508 | ||
50fbd977 | 509 | val = kmalloc(1024, GFP_KERNEL); |
3d085c74 KC |
510 | if (!val) { |
511 | free_page(p); | |
920d451f | 512 | break; |
3d085c74 | 513 | } |
920d451f LA |
514 | |
515 | base = (int *)p; | |
516 | ||
517 | *val = 0x12345678; | |
518 | base[0] = *val; | |
519 | pr_info("Value in memory before free: %x\n", base[0]); | |
520 | free_page(p); | |
521 | pr_info("Attempting to read from freed memory\n"); | |
522 | saw = base[0]; | |
523 | if (saw != *val) { | |
524 | /* Good! Poisoning happened, so declare a win. */ | |
7c0ae5be | 525 | pr_info("Memory correctly poisoned (%x)\n", saw); |
920d451f LA |
526 | BUG(); |
527 | } | |
528 | pr_info("Buddy page was not poisoned\n"); | |
529 | ||
530 | kfree(val); | |
0347af4e SK |
531 | break; |
532 | } | |
93e2f585 | 533 | case CT_SOFTLOCKUP: |
a48223f9 FW |
534 | preempt_disable(); |
535 | for (;;) | |
536 | cpu_relax(); | |
537 | break; | |
93e2f585 | 538 | case CT_HARDLOCKUP: |
a48223f9 FW |
539 | local_irq_disable(); |
540 | for (;;) | |
541 | cpu_relax(); | |
542 | break; | |
274a5855 KC |
543 | case CT_SPINLOCKUP: |
544 | /* Must be called twice to trigger. */ | |
545 | spin_lock(&lock_me_up); | |
5123662a KC |
546 | /* Let sparse know we intended to exit holding the lock. */ |
547 | __release(&lock_me_up); | |
274a5855 | 548 | break; |
93e2f585 | 549 | case CT_HUNG_TASK: |
a48223f9 FW |
550 | set_current_state(TASK_UNINTERRUPTIBLE); |
551 | schedule(); | |
552 | break; | |
cc33c537 KC |
553 | case CT_EXEC_DATA: |
554 | execute_location(data_area); | |
555 | break; | |
556 | case CT_EXEC_STACK: { | |
557 | u8 stack_area[EXEC_SIZE]; | |
558 | execute_location(stack_area); | |
559 | break; | |
560 | } | |
561 | case CT_EXEC_KMALLOC: { | |
562 | u32 *kmalloc_area = kmalloc(EXEC_SIZE, GFP_KERNEL); | |
563 | execute_location(kmalloc_area); | |
564 | kfree(kmalloc_area); | |
565 | break; | |
566 | } | |
567 | case CT_EXEC_VMALLOC: { | |
568 | u32 *vmalloc_area = vmalloc(EXEC_SIZE); | |
569 | execute_location(vmalloc_area); | |
570 | vfree(vmalloc_area); | |
571 | break; | |
572 | } | |
9ae113ce KC |
573 | case CT_EXEC_USERSPACE: { |
574 | unsigned long user_addr; | |
575 | ||
576 | user_addr = vm_mmap(NULL, 0, PAGE_SIZE, | |
577 | PROT_READ | PROT_WRITE | PROT_EXEC, | |
578 | MAP_ANONYMOUS | MAP_PRIVATE, 0); | |
579 | if (user_addr >= TASK_SIZE) { | |
580 | pr_warn("Failed to allocate user memory\n"); | |
581 | return; | |
582 | } | |
583 | execute_user_location((void *)user_addr); | |
584 | vm_munmap(user_addr, PAGE_SIZE); | |
585 | break; | |
586 | } | |
587 | case CT_ACCESS_USERSPACE: { | |
2cb202c1 | 588 | unsigned long user_addr, tmp = 0; |
9ae113ce KC |
589 | unsigned long *ptr; |
590 | ||
591 | user_addr = vm_mmap(NULL, 0, PAGE_SIZE, | |
592 | PROT_READ | PROT_WRITE | PROT_EXEC, | |
593 | MAP_ANONYMOUS | MAP_PRIVATE, 0); | |
594 | if (user_addr >= TASK_SIZE) { | |
595 | pr_warn("Failed to allocate user memory\n"); | |
596 | return; | |
597 | } | |
598 | ||
2cb202c1 SS |
599 | if (copy_to_user((void __user *)user_addr, &tmp, sizeof(tmp))) { |
600 | pr_warn("copy_to_user failed\n"); | |
601 | vm_munmap(user_addr, PAGE_SIZE); | |
602 | return; | |
603 | } | |
604 | ||
9ae113ce | 605 | ptr = (unsigned long *)user_addr; |
aac416fc KC |
606 | |
607 | pr_info("attempting bad read at %p\n", ptr); | |
9ae113ce KC |
608 | tmp = *ptr; |
609 | tmp += 0xc0dec0de; | |
aac416fc KC |
610 | |
611 | pr_info("attempting bad write at %p\n", ptr); | |
9ae113ce KC |
612 | *ptr = tmp; |
613 | ||
614 | vm_munmap(user_addr, PAGE_SIZE); | |
615 | ||
616 | break; | |
617 | } | |
618 | case CT_WRITE_RO: { | |
7cca071c KC |
619 | /* Explicitly cast away "const" for the test. */ |
620 | unsigned long *ptr = (unsigned long *)&rodata; | |
9ae113ce | 621 | |
7cca071c KC |
622 | pr_info("attempting bad rodata write at %p\n", ptr); |
623 | *ptr ^= 0xabcd1234; | |
aac416fc | 624 | |
7cca071c KC |
625 | break; |
626 | } | |
627 | case CT_WRITE_RO_AFTER_INIT: { | |
628 | unsigned long *ptr = &ro_after_init; | |
629 | ||
630 | /* | |
631 | * Verify we were written to during init. Since an Oops | |
632 | * is considered a "success", a failure is to just skip the | |
633 | * real test. | |
634 | */ | |
635 | if ((*ptr & 0xAA) != 0xAA) { | |
636 | pr_info("%p was NOT written during init!?\n", ptr); | |
637 | break; | |
638 | } | |
639 | ||
640 | pr_info("attempting bad ro_after_init write at %p\n", ptr); | |
9ae113ce KC |
641 | *ptr ^= 0xabcd1234; |
642 | ||
643 | break; | |
644 | } | |
dc2b9e90 KC |
645 | case CT_WRITE_KERN: { |
646 | size_t size; | |
647 | unsigned char *ptr; | |
648 | ||
649 | size = (unsigned long)do_overwritten - | |
650 | (unsigned long)do_nothing; | |
651 | ptr = (unsigned char *)do_overwritten; | |
652 | ||
653 | pr_info("attempting bad %zu byte write at %p\n", size, ptr); | |
654 | memcpy(ptr, (unsigned char *)do_nothing, size); | |
655 | flush_icache_range((unsigned long)ptr, | |
656 | (unsigned long)(ptr + size)); | |
657 | ||
658 | do_overwritten(); | |
659 | break; | |
660 | } | |
5fd9e480 DW |
661 | case CT_WRAP_ATOMIC: { |
662 | atomic_t under = ATOMIC_INIT(INT_MIN); | |
663 | atomic_t over = ATOMIC_INIT(INT_MAX); | |
664 | ||
665 | pr_info("attempting atomic underflow\n"); | |
666 | atomic_dec(&under); | |
667 | pr_info("attempting atomic overflow\n"); | |
668 | atomic_inc(&over); | |
669 | ||
670 | return; | |
671 | } | |
93e2f585 | 672 | case CT_NONE: |
0347af4e SK |
673 | default: |
674 | break; | |
675 | } | |
676 | ||
677 | } | |
678 | ||
679 | static void lkdtm_handler(void) | |
680 | { | |
aa2c96d6 | 681 | unsigned long flags; |
92618184 | 682 | bool do_it = false; |
aa2c96d6 JH |
683 | |
684 | spin_lock_irqsave(&count_lock, flags); | |
0347af4e | 685 | count--; |
feac6e21 KC |
686 | pr_info("Crash point %s of type %s hit, trigger in %d rounds\n", |
687 | cp_name_to_str(cpoint), cp_type_to_str(cptype), count); | |
8bb31b9d AG |
688 | |
689 | if (count == 0) { | |
92618184 | 690 | do_it = true; |
8bb31b9d AG |
691 | count = cpoint_count; |
692 | } | |
aa2c96d6 | 693 | spin_unlock_irqrestore(&count_lock, flags); |
92618184 CW |
694 | |
695 | if (do_it) | |
696 | lkdtm_do_action(cptype); | |
8bb31b9d AG |
697 | } |
698 | ||
0347af4e | 699 | static int lkdtm_register_cpoint(enum cname which) |
8bb31b9d AG |
700 | { |
701 | int ret; | |
702 | ||
93e2f585 | 703 | cpoint = CN_INVALID; |
0347af4e SK |
704 | if (lkdtm.entry != NULL) |
705 | unregister_jprobe(&lkdtm); | |
8bb31b9d | 706 | |
0347af4e | 707 | switch (which) { |
93e2f585 | 708 | case CN_DIRECT: |
0347af4e SK |
709 | lkdtm_do_action(cptype); |
710 | return 0; | |
93e2f585 | 711 | case CN_INT_HARDWARE_ENTRY: |
f58f2fa9 | 712 | lkdtm.kp.symbol_name = "do_IRQ"; |
8bb31b9d AG |
713 | lkdtm.entry = (kprobe_opcode_t*) jp_do_irq; |
714 | break; | |
93e2f585 | 715 | case CN_INT_HW_IRQ_EN: |
8bb31b9d AG |
716 | lkdtm.kp.symbol_name = "handle_IRQ_event"; |
717 | lkdtm.entry = (kprobe_opcode_t*) jp_handle_irq_event; | |
718 | break; | |
93e2f585 | 719 | case CN_INT_TASKLET_ENTRY: |
8bb31b9d AG |
720 | lkdtm.kp.symbol_name = "tasklet_action"; |
721 | lkdtm.entry = (kprobe_opcode_t*) jp_tasklet_action; | |
722 | break; | |
93e2f585 | 723 | case CN_FS_DEVRW: |
8bb31b9d AG |
724 | lkdtm.kp.symbol_name = "ll_rw_block"; |
725 | lkdtm.entry = (kprobe_opcode_t*) jp_ll_rw_block; | |
726 | break; | |
93e2f585 | 727 | case CN_MEM_SWAPOUT: |
18a61e4a AG |
728 | lkdtm.kp.symbol_name = "shrink_inactive_list"; |
729 | lkdtm.entry = (kprobe_opcode_t*) jp_shrink_inactive_list; | |
8bb31b9d | 730 | break; |
93e2f585 | 731 | case CN_TIMERADD: |
8bb31b9d AG |
732 | lkdtm.kp.symbol_name = "hrtimer_start"; |
733 | lkdtm.entry = (kprobe_opcode_t*) jp_hrtimer_start; | |
734 | break; | |
93e2f585 | 735 | case CN_SCSI_DISPATCH_CMD: |
8bb31b9d AG |
736 | lkdtm.kp.symbol_name = "scsi_dispatch_cmd"; |
737 | lkdtm.entry = (kprobe_opcode_t*) jp_scsi_dispatch_cmd; | |
738 | break; | |
93e2f585 | 739 | case CN_IDE_CORE_CP: |
8bb31b9d AG |
740 | #ifdef CONFIG_IDE |
741 | lkdtm.kp.symbol_name = "generic_ide_ioctl"; | |
742 | lkdtm.entry = (kprobe_opcode_t*) jp_generic_ide_ioctl; | |
743 | #else | |
feac6e21 | 744 | pr_info("Crash point not available\n"); |
0347af4e | 745 | return -EINVAL; |
8bb31b9d AG |
746 | #endif |
747 | break; | |
748 | default: | |
feac6e21 | 749 | pr_info("Invalid Crash Point\n"); |
0347af4e | 750 | return -EINVAL; |
8bb31b9d AG |
751 | } |
752 | ||
0347af4e | 753 | cpoint = which; |
8bb31b9d | 754 | if ((ret = register_jprobe(&lkdtm)) < 0) { |
feac6e21 | 755 | pr_info("Couldn't register jprobe\n"); |
93e2f585 | 756 | cpoint = CN_INVALID; |
0347af4e SK |
757 | } |
758 | ||
759 | return ret; | |
760 | } | |
761 | ||
762 | static ssize_t do_register_entry(enum cname which, struct file *f, | |
763 | const char __user *user_buf, size_t count, loff_t *off) | |
764 | { | |
765 | char *buf; | |
766 | int err; | |
767 | ||
768 | if (count >= PAGE_SIZE) | |
769 | return -EINVAL; | |
770 | ||
771 | buf = (char *)__get_free_page(GFP_KERNEL); | |
772 | if (!buf) | |
773 | return -ENOMEM; | |
774 | if (copy_from_user(buf, user_buf, count)) { | |
775 | free_page((unsigned long) buf); | |
776 | return -EFAULT; | |
777 | } | |
778 | /* NULL-terminate and remove enter */ | |
779 | buf[count] = '\0'; | |
780 | strim(buf); | |
781 | ||
782 | cptype = parse_cp_type(buf, count); | |
783 | free_page((unsigned long) buf); | |
784 | ||
93e2f585 | 785 | if (cptype == CT_NONE) |
0347af4e SK |
786 | return -EINVAL; |
787 | ||
788 | err = lkdtm_register_cpoint(which); | |
789 | if (err < 0) | |
790 | return err; | |
791 | ||
792 | *off += count; | |
793 | ||
794 | return count; | |
795 | } | |
796 | ||
797 | /* Generic read callback that just prints out the available crash types */ | |
798 | static ssize_t lkdtm_debugfs_read(struct file *f, char __user *user_buf, | |
799 | size_t count, loff_t *off) | |
800 | { | |
801 | char *buf; | |
802 | int i, n, out; | |
803 | ||
804 | buf = (char *)__get_free_page(GFP_KERNEL); | |
086ff4b3 AC |
805 | if (buf == NULL) |
806 | return -ENOMEM; | |
0347af4e SK |
807 | |
808 | n = snprintf(buf, PAGE_SIZE, "Available crash types:\n"); | |
809 | for (i = 0; i < ARRAY_SIZE(cp_type); i++) | |
810 | n += snprintf(buf + n, PAGE_SIZE - n, "%s\n", cp_type[i]); | |
811 | buf[n] = '\0'; | |
812 | ||
813 | out = simple_read_from_buffer(user_buf, count, off, | |
814 | buf, n); | |
815 | free_page((unsigned long) buf); | |
816 | ||
817 | return out; | |
818 | } | |
819 | ||
820 | static int lkdtm_debugfs_open(struct inode *inode, struct file *file) | |
821 | { | |
822 | return 0; | |
823 | } | |
824 | ||
825 | ||
826 | static ssize_t int_hardware_entry(struct file *f, const char __user *buf, | |
827 | size_t count, loff_t *off) | |
828 | { | |
93e2f585 | 829 | return do_register_entry(CN_INT_HARDWARE_ENTRY, f, buf, count, off); |
0347af4e SK |
830 | } |
831 | ||
832 | static ssize_t int_hw_irq_en(struct file *f, const char __user *buf, | |
833 | size_t count, loff_t *off) | |
834 | { | |
93e2f585 | 835 | return do_register_entry(CN_INT_HW_IRQ_EN, f, buf, count, off); |
0347af4e SK |
836 | } |
837 | ||
838 | static ssize_t int_tasklet_entry(struct file *f, const char __user *buf, | |
839 | size_t count, loff_t *off) | |
840 | { | |
93e2f585 | 841 | return do_register_entry(CN_INT_TASKLET_ENTRY, f, buf, count, off); |
0347af4e SK |
842 | } |
843 | ||
844 | static ssize_t fs_devrw_entry(struct file *f, const char __user *buf, | |
845 | size_t count, loff_t *off) | |
846 | { | |
93e2f585 | 847 | return do_register_entry(CN_FS_DEVRW, f, buf, count, off); |
0347af4e SK |
848 | } |
849 | ||
850 | static ssize_t mem_swapout_entry(struct file *f, const char __user *buf, | |
851 | size_t count, loff_t *off) | |
852 | { | |
93e2f585 | 853 | return do_register_entry(CN_MEM_SWAPOUT, f, buf, count, off); |
0347af4e SK |
854 | } |
855 | ||
856 | static ssize_t timeradd_entry(struct file *f, const char __user *buf, | |
857 | size_t count, loff_t *off) | |
858 | { | |
93e2f585 | 859 | return do_register_entry(CN_TIMERADD, f, buf, count, off); |
0347af4e SK |
860 | } |
861 | ||
862 | static ssize_t scsi_dispatch_cmd_entry(struct file *f, | |
863 | const char __user *buf, size_t count, loff_t *off) | |
864 | { | |
93e2f585 | 865 | return do_register_entry(CN_SCSI_DISPATCH_CMD, f, buf, count, off); |
0347af4e SK |
866 | } |
867 | ||
868 | static ssize_t ide_core_cp_entry(struct file *f, const char __user *buf, | |
869 | size_t count, loff_t *off) | |
870 | { | |
93e2f585 | 871 | return do_register_entry(CN_IDE_CORE_CP, f, buf, count, off); |
0347af4e SK |
872 | } |
873 | ||
874 | /* Special entry to just crash directly. Available without KPROBEs */ | |
875 | static ssize_t direct_entry(struct file *f, const char __user *user_buf, | |
876 | size_t count, loff_t *off) | |
877 | { | |
878 | enum ctype type; | |
879 | char *buf; | |
880 | ||
881 | if (count >= PAGE_SIZE) | |
882 | return -EINVAL; | |
883 | if (count < 1) | |
884 | return -EINVAL; | |
885 | ||
886 | buf = (char *)__get_free_page(GFP_KERNEL); | |
887 | if (!buf) | |
888 | return -ENOMEM; | |
889 | if (copy_from_user(buf, user_buf, count)) { | |
890 | free_page((unsigned long) buf); | |
891 | return -EFAULT; | |
892 | } | |
893 | /* NULL-terminate and remove enter */ | |
894 | buf[count] = '\0'; | |
895 | strim(buf); | |
896 | ||
897 | type = parse_cp_type(buf, count); | |
898 | free_page((unsigned long) buf); | |
93e2f585 | 899 | if (type == CT_NONE) |
0347af4e SK |
900 | return -EINVAL; |
901 | ||
feac6e21 | 902 | pr_info("Performing direct entry %s\n", cp_type_to_str(type)); |
0347af4e SK |
903 | lkdtm_do_action(type); |
904 | *off += count; | |
905 | ||
906 | return count; | |
907 | } | |
908 | ||
909 | struct crash_entry { | |
910 | const char *name; | |
911 | const struct file_operations fops; | |
912 | }; | |
913 | ||
914 | static const struct crash_entry crash_entries[] = { | |
915 | {"DIRECT", {.read = lkdtm_debugfs_read, | |
05271ec4 | 916 | .llseek = generic_file_llseek, |
0347af4e SK |
917 | .open = lkdtm_debugfs_open, |
918 | .write = direct_entry} }, | |
919 | {"INT_HARDWARE_ENTRY", {.read = lkdtm_debugfs_read, | |
05271ec4 | 920 | .llseek = generic_file_llseek, |
0347af4e SK |
921 | .open = lkdtm_debugfs_open, |
922 | .write = int_hardware_entry} }, | |
923 | {"INT_HW_IRQ_EN", {.read = lkdtm_debugfs_read, | |
05271ec4 | 924 | .llseek = generic_file_llseek, |
0347af4e SK |
925 | .open = lkdtm_debugfs_open, |
926 | .write = int_hw_irq_en} }, | |
927 | {"INT_TASKLET_ENTRY", {.read = lkdtm_debugfs_read, | |
05271ec4 | 928 | .llseek = generic_file_llseek, |
0347af4e SK |
929 | .open = lkdtm_debugfs_open, |
930 | .write = int_tasklet_entry} }, | |
931 | {"FS_DEVRW", {.read = lkdtm_debugfs_read, | |
05271ec4 | 932 | .llseek = generic_file_llseek, |
0347af4e SK |
933 | .open = lkdtm_debugfs_open, |
934 | .write = fs_devrw_entry} }, | |
935 | {"MEM_SWAPOUT", {.read = lkdtm_debugfs_read, | |
05271ec4 | 936 | .llseek = generic_file_llseek, |
0347af4e SK |
937 | .open = lkdtm_debugfs_open, |
938 | .write = mem_swapout_entry} }, | |
939 | {"TIMERADD", {.read = lkdtm_debugfs_read, | |
05271ec4 | 940 | .llseek = generic_file_llseek, |
0347af4e SK |
941 | .open = lkdtm_debugfs_open, |
942 | .write = timeradd_entry} }, | |
943 | {"SCSI_DISPATCH_CMD", {.read = lkdtm_debugfs_read, | |
05271ec4 | 944 | .llseek = generic_file_llseek, |
0347af4e SK |
945 | .open = lkdtm_debugfs_open, |
946 | .write = scsi_dispatch_cmd_entry} }, | |
947 | {"IDE_CORE_CP", {.read = lkdtm_debugfs_read, | |
05271ec4 | 948 | .llseek = generic_file_llseek, |
0347af4e SK |
949 | .open = lkdtm_debugfs_open, |
950 | .write = ide_core_cp_entry} }, | |
951 | }; | |
952 | ||
953 | static struct dentry *lkdtm_debugfs_root; | |
954 | ||
955 | static int __init lkdtm_module_init(void) | |
956 | { | |
957 | int ret = -EINVAL; | |
958 | int n_debugfs_entries = 1; /* Assume only the direct entry */ | |
959 | int i; | |
960 | ||
7cca071c KC |
961 | /* Make sure we can write to __ro_after_init values during __init */ |
962 | ro_after_init |= 0xAA; | |
963 | ||
0347af4e SK |
964 | /* Register debugfs interface */ |
965 | lkdtm_debugfs_root = debugfs_create_dir("provoke-crash", NULL); | |
966 | if (!lkdtm_debugfs_root) { | |
feac6e21 | 967 | pr_err("creating root dir failed\n"); |
0347af4e SK |
968 | return -ENODEV; |
969 | } | |
970 | ||
971 | #ifdef CONFIG_KPROBES | |
972 | n_debugfs_entries = ARRAY_SIZE(crash_entries); | |
973 | #endif | |
974 | ||
975 | for (i = 0; i < n_debugfs_entries; i++) { | |
976 | const struct crash_entry *cur = &crash_entries[i]; | |
977 | struct dentry *de; | |
978 | ||
979 | de = debugfs_create_file(cur->name, 0644, lkdtm_debugfs_root, | |
980 | NULL, &cur->fops); | |
981 | if (de == NULL) { | |
feac6e21 | 982 | pr_err("could not create %s\n", cur->name); |
0347af4e SK |
983 | goto out_err; |
984 | } | |
985 | } | |
986 | ||
987 | if (lkdtm_parse_commandline() == -EINVAL) { | |
feac6e21 | 988 | pr_info("Invalid command\n"); |
0347af4e SK |
989 | goto out_err; |
990 | } | |
991 | ||
93e2f585 | 992 | if (cpoint != CN_INVALID && cptype != CT_NONE) { |
0347af4e SK |
993 | ret = lkdtm_register_cpoint(cpoint); |
994 | if (ret < 0) { | |
feac6e21 | 995 | pr_info("Invalid crash point %d\n", cpoint); |
0347af4e SK |
996 | goto out_err; |
997 | } | |
feac6e21 KC |
998 | pr_info("Crash point %s of type %s registered\n", |
999 | cpoint_name, cpoint_type); | |
0347af4e | 1000 | } else { |
feac6e21 | 1001 | pr_info("No crash points registered, enable through debugfs\n"); |
8bb31b9d AG |
1002 | } |
1003 | ||
8bb31b9d | 1004 | return 0; |
0347af4e SK |
1005 | |
1006 | out_err: | |
1007 | debugfs_remove_recursive(lkdtm_debugfs_root); | |
1008 | return ret; | |
8bb31b9d AG |
1009 | } |
1010 | ||
2118116e | 1011 | static void __exit lkdtm_module_exit(void) |
8bb31b9d | 1012 | { |
0347af4e SK |
1013 | debugfs_remove_recursive(lkdtm_debugfs_root); |
1014 | ||
1015 | unregister_jprobe(&lkdtm); | |
feac6e21 | 1016 | pr_info("Crash point unregistered\n"); |
8bb31b9d AG |
1017 | } |
1018 | ||
1019 | module_init(lkdtm_module_init); | |
1020 | module_exit(lkdtm_module_exit); | |
1021 | ||
1022 | MODULE_LICENSE("GPL"); | |
da86920f | 1023 | MODULE_DESCRIPTION("Kprobe module for testing crash dumps"); |