Commit | Line | Data |
---|---|---|
07dfc1d0 MD |
1 | /* |
2 | * lttng-filter-validator.c | |
3 | * | |
4 | * LTTng modules filter bytecode validator. | |
5 | * | |
bbf3aef5 | 6 | * Copyright (C) 2010-2016 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
07dfc1d0 | 7 | * |
bbf3aef5 MD |
8 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
9 | * of this software and associated documentation files (the "Software"), to deal | |
10 | * in the Software without restriction, including without limitation the rights | |
11 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell | |
12 | * copies of the Software, and to permit persons to whom the Software is | |
13 | * furnished to do so, subject to the following conditions: | |
07dfc1d0 | 14 | * |
bbf3aef5 MD |
15 | * The above copyright notice and this permission notice shall be included in |
16 | * all copies or substantial portions of the Software. | |
07dfc1d0 | 17 | * |
bbf3aef5 MD |
18 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
19 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
20 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE | |
21 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | |
22 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, | |
23 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE | |
24 | * SOFTWARE. | |
07dfc1d0 MD |
25 | */ |
26 | ||
499cc3f7 | 27 | #include <linux/types.h> |
07dfc1d0 MD |
28 | #include <linux/jhash.h> |
29 | #include <linux/slab.h> | |
30 | ||
241ae9a8 MD |
31 | #include <wrapper/list.h> |
32 | #include <lttng-filter.h> | |
07dfc1d0 MD |
33 | |
34 | #define MERGE_POINT_TABLE_BITS 7 | |
35 | #define MERGE_POINT_TABLE_SIZE (1U << MERGE_POINT_TABLE_BITS) | |
36 | ||
37 | /* merge point table node */ | |
38 | struct mp_node { | |
39 | struct hlist_node node; | |
40 | ||
41 | /* Context at merge point */ | |
42 | struct vstack stack; | |
43 | unsigned long target_pc; | |
44 | }; | |
45 | ||
46 | struct mp_table { | |
47 | struct hlist_head mp_head[MERGE_POINT_TABLE_SIZE]; | |
48 | }; | |
49 | ||
50 | static | |
51 | int lttng_hash_match(struct mp_node *mp_node, unsigned long key_pc) | |
52 | { | |
53 | if (mp_node->target_pc == key_pc) | |
54 | return 1; | |
55 | else | |
56 | return 0; | |
57 | } | |
58 | ||
59 | static | |
60 | int merge_points_compare(const struct vstack *stacka, | |
61 | const struct vstack *stackb) | |
62 | { | |
63 | int i, len; | |
64 | ||
65 | if (stacka->top != stackb->top) | |
66 | return 1; | |
67 | len = stacka->top + 1; | |
68 | WARN_ON_ONCE(len < 0); | |
69 | for (i = 0; i < len; i++) { | |
70 | if (stacka->e[i].type != stackb->e[i].type) | |
71 | return 1; | |
72 | } | |
73 | return 0; | |
74 | } | |
75 | ||
76 | static | |
77 | int merge_point_add_check(struct mp_table *mp_table, unsigned long target_pc, | |
78 | const struct vstack *stack) | |
79 | { | |
80 | struct mp_node *mp_node; | |
81 | unsigned long hash = jhash_1word(target_pc, 0); | |
82 | struct hlist_head *head; | |
83 | struct mp_node *lookup_node; | |
84 | int found = 0; | |
85 | ||
86 | dbg_printk("Filter: adding merge point at offset %lu, hash %lu\n", | |
87 | target_pc, hash); | |
88 | mp_node = kzalloc(sizeof(struct mp_node), GFP_KERNEL); | |
89 | if (!mp_node) | |
90 | return -ENOMEM; | |
91 | mp_node->target_pc = target_pc; | |
92 | memcpy(&mp_node->stack, stack, sizeof(mp_node->stack)); | |
93 | ||
94 | head = &mp_table->mp_head[hash & (MERGE_POINT_TABLE_SIZE - 1)]; | |
d216ecae | 95 | lttng_hlist_for_each_entry(lookup_node, head, node) { |
07dfc1d0 MD |
96 | if (lttng_hash_match(lookup_node, target_pc)) { |
97 | found = 1; | |
98 | break; | |
99 | } | |
100 | } | |
101 | if (found) { | |
102 | /* Key already present */ | |
103 | dbg_printk("Filter: compare merge points for offset %lu, hash %lu\n", | |
104 | target_pc, hash); | |
105 | kfree(mp_node); | |
106 | if (merge_points_compare(stack, &lookup_node->stack)) { | |
107 | printk(KERN_WARNING "Merge points differ for offset %lu\n", | |
108 | target_pc); | |
109 | return -EINVAL; | |
110 | } | |
5e13eb3c MD |
111 | } else { |
112 | hlist_add_head(&mp_node->node, head); | |
07dfc1d0 | 113 | } |
07dfc1d0 MD |
114 | return 0; |
115 | } | |
116 | ||
117 | /* | |
118 | * Binary comparators use top of stack and top of stack -1. | |
119 | */ | |
120 | static | |
121 | int bin_op_compare_check(struct vstack *stack, const char *str) | |
122 | { | |
123 | if (unlikely(!vstack_ax(stack) || !vstack_bx(stack))) | |
124 | goto error_unknown; | |
125 | ||
126 | switch (vstack_ax(stack)->type) { | |
127 | default: | |
128 | case REG_DOUBLE: | |
129 | goto error_unknown; | |
130 | ||
131 | case REG_STRING: | |
132 | switch (vstack_bx(stack)->type) { | |
133 | default: | |
134 | case REG_DOUBLE: | |
135 | goto error_unknown; | |
136 | ||
137 | case REG_STRING: | |
138 | break; | |
139 | case REG_S64: | |
140 | goto error_mismatch; | |
141 | } | |
142 | break; | |
143 | case REG_S64: | |
144 | switch (vstack_bx(stack)->type) { | |
145 | default: | |
146 | case REG_DOUBLE: | |
147 | goto error_unknown; | |
148 | ||
149 | case REG_STRING: | |
150 | goto error_mismatch; | |
151 | ||
152 | case REG_S64: | |
153 | break; | |
154 | } | |
155 | break; | |
156 | } | |
157 | return 0; | |
158 | ||
159 | error_unknown: | |
160 | return -EINVAL; | |
161 | ||
162 | error_mismatch: | |
163 | printk(KERN_WARNING "type mismatch for '%s' binary operator\n", str); | |
164 | return -EINVAL; | |
165 | } | |
166 | ||
167 | /* | |
168 | * Validate bytecode range overflow within the validation pass. | |
169 | * Called for each instruction encountered. | |
170 | */ | |
171 | static | |
172 | int bytecode_validate_overflow(struct bytecode_runtime *bytecode, | |
7962cb86 | 173 | char *start_pc, char *pc) |
07dfc1d0 MD |
174 | { |
175 | int ret = 0; | |
176 | ||
177 | switch (*(filter_opcode_t *) pc) { | |
178 | case FILTER_OP_UNKNOWN: | |
179 | default: | |
180 | { | |
181 | printk(KERN_WARNING "unknown bytecode op %u\n", | |
182 | (unsigned int) *(filter_opcode_t *) pc); | |
183 | ret = -EINVAL; | |
184 | break; | |
185 | } | |
186 | ||
187 | case FILTER_OP_RETURN: | |
188 | { | |
189 | if (unlikely(pc + sizeof(struct return_op) | |
190 | > start_pc + bytecode->len)) { | |
191 | ret = -ERANGE; | |
192 | } | |
193 | break; | |
194 | } | |
195 | ||
196 | /* binary */ | |
197 | case FILTER_OP_MUL: | |
198 | case FILTER_OP_DIV: | |
199 | case FILTER_OP_MOD: | |
200 | case FILTER_OP_PLUS: | |
201 | case FILTER_OP_MINUS: | |
202 | case FILTER_OP_RSHIFT: | |
203 | case FILTER_OP_LSHIFT: | |
204 | case FILTER_OP_BIN_AND: | |
205 | case FILTER_OP_BIN_OR: | |
206 | case FILTER_OP_BIN_XOR: | |
207 | case FILTER_OP_EQ_DOUBLE: | |
208 | case FILTER_OP_NE_DOUBLE: | |
209 | case FILTER_OP_GT_DOUBLE: | |
210 | case FILTER_OP_LT_DOUBLE: | |
211 | case FILTER_OP_GE_DOUBLE: | |
212 | case FILTER_OP_LE_DOUBLE: | |
213 | /* Floating point */ | |
214 | case FILTER_OP_EQ_DOUBLE_S64: | |
215 | case FILTER_OP_NE_DOUBLE_S64: | |
216 | case FILTER_OP_GT_DOUBLE_S64: | |
217 | case FILTER_OP_LT_DOUBLE_S64: | |
218 | case FILTER_OP_GE_DOUBLE_S64: | |
219 | case FILTER_OP_LE_DOUBLE_S64: | |
220 | case FILTER_OP_EQ_S64_DOUBLE: | |
221 | case FILTER_OP_NE_S64_DOUBLE: | |
222 | case FILTER_OP_GT_S64_DOUBLE: | |
223 | case FILTER_OP_LT_S64_DOUBLE: | |
224 | case FILTER_OP_GE_S64_DOUBLE: | |
225 | case FILTER_OP_LE_S64_DOUBLE: | |
226 | case FILTER_OP_LOAD_FIELD_REF_DOUBLE: | |
227 | case FILTER_OP_GET_CONTEXT_REF_DOUBLE: | |
228 | case FILTER_OP_LOAD_DOUBLE: | |
229 | case FILTER_OP_CAST_DOUBLE_TO_S64: | |
230 | case FILTER_OP_UNARY_PLUS_DOUBLE: | |
231 | case FILTER_OP_UNARY_MINUS_DOUBLE: | |
232 | case FILTER_OP_UNARY_NOT_DOUBLE: | |
233 | { | |
234 | printk(KERN_WARNING "unsupported bytecode op %u\n", | |
235 | (unsigned int) *(filter_opcode_t *) pc); | |
236 | ret = -EINVAL; | |
237 | break; | |
238 | } | |
239 | ||
240 | case FILTER_OP_EQ: | |
241 | case FILTER_OP_NE: | |
242 | case FILTER_OP_GT: | |
243 | case FILTER_OP_LT: | |
244 | case FILTER_OP_GE: | |
245 | case FILTER_OP_LE: | |
246 | case FILTER_OP_EQ_STRING: | |
247 | case FILTER_OP_NE_STRING: | |
248 | case FILTER_OP_GT_STRING: | |
249 | case FILTER_OP_LT_STRING: | |
250 | case FILTER_OP_GE_STRING: | |
251 | case FILTER_OP_LE_STRING: | |
252 | case FILTER_OP_EQ_S64: | |
253 | case FILTER_OP_NE_S64: | |
254 | case FILTER_OP_GT_S64: | |
255 | case FILTER_OP_LT_S64: | |
256 | case FILTER_OP_GE_S64: | |
257 | case FILTER_OP_LE_S64: | |
258 | { | |
259 | if (unlikely(pc + sizeof(struct binary_op) | |
260 | > start_pc + bytecode->len)) { | |
261 | ret = -ERANGE; | |
262 | } | |
263 | break; | |
264 | } | |
265 | ||
266 | /* unary */ | |
267 | case FILTER_OP_UNARY_PLUS: | |
268 | case FILTER_OP_UNARY_MINUS: | |
269 | case FILTER_OP_UNARY_NOT: | |
270 | case FILTER_OP_UNARY_PLUS_S64: | |
271 | case FILTER_OP_UNARY_MINUS_S64: | |
272 | case FILTER_OP_UNARY_NOT_S64: | |
273 | { | |
274 | if (unlikely(pc + sizeof(struct unary_op) | |
275 | > start_pc + bytecode->len)) { | |
276 | ret = -ERANGE; | |
277 | } | |
278 | break; | |
279 | } | |
280 | ||
281 | /* logical */ | |
282 | case FILTER_OP_AND: | |
283 | case FILTER_OP_OR: | |
284 | { | |
285 | if (unlikely(pc + sizeof(struct logical_op) | |
286 | > start_pc + bytecode->len)) { | |
287 | ret = -ERANGE; | |
288 | } | |
289 | break; | |
290 | } | |
291 | ||
292 | /* load field ref */ | |
293 | case FILTER_OP_LOAD_FIELD_REF: | |
294 | { | |
295 | printk(KERN_WARNING "Unknown field ref type\n"); | |
296 | ret = -EINVAL; | |
297 | break; | |
298 | } | |
299 | /* get context ref */ | |
300 | case FILTER_OP_GET_CONTEXT_REF: | |
301 | { | |
302 | printk(KERN_WARNING "Unknown field ref type\n"); | |
303 | ret = -EINVAL; | |
304 | break; | |
305 | } | |
306 | case FILTER_OP_LOAD_FIELD_REF_STRING: | |
307 | case FILTER_OP_LOAD_FIELD_REF_SEQUENCE: | |
f127e61e MD |
308 | case FILTER_OP_LOAD_FIELD_REF_USER_STRING: |
309 | case FILTER_OP_LOAD_FIELD_REF_USER_SEQUENCE: | |
07dfc1d0 MD |
310 | case FILTER_OP_LOAD_FIELD_REF_S64: |
311 | case FILTER_OP_GET_CONTEXT_REF_STRING: | |
312 | case FILTER_OP_GET_CONTEXT_REF_S64: | |
313 | { | |
314 | if (unlikely(pc + sizeof(struct load_op) + sizeof(struct field_ref) | |
315 | > start_pc + bytecode->len)) { | |
316 | ret = -ERANGE; | |
317 | } | |
318 | break; | |
319 | } | |
320 | ||
321 | /* load from immediate operand */ | |
322 | case FILTER_OP_LOAD_STRING: | |
323 | { | |
324 | struct load_op *insn = (struct load_op *) pc; | |
325 | uint32_t str_len, maxlen; | |
326 | ||
327 | if (unlikely(pc + sizeof(struct load_op) | |
328 | > start_pc + bytecode->len)) { | |
329 | ret = -ERANGE; | |
330 | break; | |
331 | } | |
332 | ||
333 | maxlen = start_pc + bytecode->len - pc - sizeof(struct load_op); | |
334 | str_len = strnlen(insn->data, maxlen); | |
335 | if (unlikely(str_len >= maxlen)) { | |
336 | /* Final '\0' not found within range */ | |
337 | ret = -ERANGE; | |
338 | } | |
339 | break; | |
340 | } | |
341 | ||
342 | case FILTER_OP_LOAD_S64: | |
343 | { | |
344 | if (unlikely(pc + sizeof(struct load_op) + sizeof(struct literal_numeric) | |
345 | > start_pc + bytecode->len)) { | |
346 | ret = -ERANGE; | |
347 | } | |
348 | break; | |
349 | } | |
350 | ||
351 | case FILTER_OP_CAST_TO_S64: | |
352 | case FILTER_OP_CAST_NOP: | |
353 | { | |
354 | if (unlikely(pc + sizeof(struct cast_op) | |
355 | > start_pc + bytecode->len)) { | |
356 | ret = -ERANGE; | |
357 | } | |
358 | break; | |
359 | } | |
360 | ||
361 | } | |
362 | ||
363 | return ret; | |
364 | } | |
365 | ||
366 | static | |
367 | unsigned long delete_all_nodes(struct mp_table *mp_table) | |
368 | { | |
369 | struct mp_node *mp_node; | |
370 | struct hlist_node *tmp; | |
371 | unsigned long nr_nodes = 0; | |
372 | int i; | |
373 | ||
374 | for (i = 0; i < MERGE_POINT_TABLE_SIZE; i++) { | |
375 | struct hlist_head *head; | |
376 | ||
377 | head = &mp_table->mp_head[i]; | |
d216ecae | 378 | lttng_hlist_for_each_entry_safe(mp_node, tmp, head, node) { |
07dfc1d0 MD |
379 | kfree(mp_node); |
380 | nr_nodes++; | |
381 | } | |
382 | } | |
383 | return nr_nodes; | |
384 | } | |
385 | ||
386 | /* | |
387 | * Return value: | |
388 | * 0: success | |
389 | * <0: error | |
390 | */ | |
391 | static | |
392 | int validate_instruction_context(struct bytecode_runtime *bytecode, | |
393 | struct vstack *stack, | |
7962cb86 MD |
394 | char *start_pc, |
395 | char *pc) | |
07dfc1d0 MD |
396 | { |
397 | int ret = 0; | |
398 | ||
399 | switch (*(filter_opcode_t *) pc) { | |
400 | case FILTER_OP_UNKNOWN: | |
401 | default: | |
402 | { | |
403 | printk(KERN_WARNING "unknown bytecode op %u\n", | |
404 | (unsigned int) *(filter_opcode_t *) pc); | |
405 | ret = -EINVAL; | |
406 | goto end; | |
407 | } | |
408 | ||
409 | case FILTER_OP_RETURN: | |
410 | { | |
411 | goto end; | |
412 | } | |
413 | ||
414 | /* binary */ | |
415 | case FILTER_OP_MUL: | |
416 | case FILTER_OP_DIV: | |
417 | case FILTER_OP_MOD: | |
418 | case FILTER_OP_PLUS: | |
419 | case FILTER_OP_MINUS: | |
420 | case FILTER_OP_RSHIFT: | |
421 | case FILTER_OP_LSHIFT: | |
422 | case FILTER_OP_BIN_AND: | |
423 | case FILTER_OP_BIN_OR: | |
424 | case FILTER_OP_BIN_XOR: | |
425 | /* Floating point */ | |
426 | case FILTER_OP_EQ_DOUBLE: | |
427 | case FILTER_OP_NE_DOUBLE: | |
428 | case FILTER_OP_GT_DOUBLE: | |
429 | case FILTER_OP_LT_DOUBLE: | |
430 | case FILTER_OP_GE_DOUBLE: | |
431 | case FILTER_OP_LE_DOUBLE: | |
432 | case FILTER_OP_EQ_DOUBLE_S64: | |
433 | case FILTER_OP_NE_DOUBLE_S64: | |
434 | case FILTER_OP_GT_DOUBLE_S64: | |
435 | case FILTER_OP_LT_DOUBLE_S64: | |
436 | case FILTER_OP_GE_DOUBLE_S64: | |
437 | case FILTER_OP_LE_DOUBLE_S64: | |
438 | case FILTER_OP_EQ_S64_DOUBLE: | |
439 | case FILTER_OP_NE_S64_DOUBLE: | |
440 | case FILTER_OP_GT_S64_DOUBLE: | |
441 | case FILTER_OP_LT_S64_DOUBLE: | |
442 | case FILTER_OP_GE_S64_DOUBLE: | |
443 | case FILTER_OP_LE_S64_DOUBLE: | |
444 | case FILTER_OP_UNARY_PLUS_DOUBLE: | |
445 | case FILTER_OP_UNARY_MINUS_DOUBLE: | |
446 | case FILTER_OP_UNARY_NOT_DOUBLE: | |
447 | case FILTER_OP_LOAD_FIELD_REF_DOUBLE: | |
448 | case FILTER_OP_LOAD_DOUBLE: | |
449 | case FILTER_OP_CAST_DOUBLE_TO_S64: | |
450 | case FILTER_OP_GET_CONTEXT_REF_DOUBLE: | |
451 | { | |
452 | printk(KERN_WARNING "unsupported bytecode op %u\n", | |
453 | (unsigned int) *(filter_opcode_t *) pc); | |
454 | ret = -EINVAL; | |
455 | goto end; | |
456 | } | |
457 | ||
458 | case FILTER_OP_EQ: | |
459 | { | |
460 | ret = bin_op_compare_check(stack, "=="); | |
461 | if (ret) | |
462 | goto end; | |
463 | break; | |
464 | } | |
465 | case FILTER_OP_NE: | |
466 | { | |
467 | ret = bin_op_compare_check(stack, "!="); | |
468 | if (ret) | |
469 | goto end; | |
470 | break; | |
471 | } | |
472 | case FILTER_OP_GT: | |
473 | { | |
474 | ret = bin_op_compare_check(stack, ">"); | |
475 | if (ret) | |
476 | goto end; | |
477 | break; | |
478 | } | |
479 | case FILTER_OP_LT: | |
480 | { | |
481 | ret = bin_op_compare_check(stack, "<"); | |
482 | if (ret) | |
483 | goto end; | |
484 | break; | |
485 | } | |
486 | case FILTER_OP_GE: | |
487 | { | |
488 | ret = bin_op_compare_check(stack, ">="); | |
489 | if (ret) | |
490 | goto end; | |
491 | break; | |
492 | } | |
493 | case FILTER_OP_LE: | |
494 | { | |
495 | ret = bin_op_compare_check(stack, "<="); | |
496 | if (ret) | |
497 | goto end; | |
498 | break; | |
499 | } | |
500 | ||
501 | case FILTER_OP_EQ_STRING: | |
502 | case FILTER_OP_NE_STRING: | |
503 | case FILTER_OP_GT_STRING: | |
504 | case FILTER_OP_LT_STRING: | |
505 | case FILTER_OP_GE_STRING: | |
506 | case FILTER_OP_LE_STRING: | |
507 | { | |
508 | if (!vstack_ax(stack) || !vstack_bx(stack)) { | |
509 | printk(KERN_WARNING "Empty stack\n"); | |
510 | ret = -EINVAL; | |
511 | goto end; | |
512 | } | |
513 | if (vstack_ax(stack)->type != REG_STRING | |
514 | || vstack_bx(stack)->type != REG_STRING) { | |
515 | printk(KERN_WARNING "Unexpected register type for string comparator\n"); | |
516 | ret = -EINVAL; | |
517 | goto end; | |
518 | } | |
519 | break; | |
520 | } | |
521 | ||
522 | case FILTER_OP_EQ_S64: | |
523 | case FILTER_OP_NE_S64: | |
524 | case FILTER_OP_GT_S64: | |
525 | case FILTER_OP_LT_S64: | |
526 | case FILTER_OP_GE_S64: | |
527 | case FILTER_OP_LE_S64: | |
528 | { | |
529 | if (!vstack_ax(stack) || !vstack_bx(stack)) { | |
530 | printk(KERN_WARNING "Empty stack\n"); | |
531 | ret = -EINVAL; | |
532 | goto end; | |
533 | } | |
534 | if (vstack_ax(stack)->type != REG_S64 | |
535 | || vstack_bx(stack)->type != REG_S64) { | |
536 | printk(KERN_WARNING "Unexpected register type for s64 comparator\n"); | |
537 | ret = -EINVAL; | |
538 | goto end; | |
539 | } | |
540 | break; | |
541 | } | |
542 | ||
543 | /* unary */ | |
544 | case FILTER_OP_UNARY_PLUS: | |
545 | case FILTER_OP_UNARY_MINUS: | |
546 | case FILTER_OP_UNARY_NOT: | |
547 | { | |
548 | if (!vstack_ax(stack)) { | |
549 | printk(KERN_WARNING "Empty stack\n"); | |
550 | ret = -EINVAL; | |
551 | goto end; | |
552 | } | |
553 | switch (vstack_ax(stack)->type) { | |
554 | default: | |
555 | case REG_DOUBLE: | |
556 | printk(KERN_WARNING "unknown register type\n"); | |
557 | ret = -EINVAL; | |
558 | goto end; | |
559 | ||
560 | case REG_STRING: | |
561 | printk(KERN_WARNING "Unary op can only be applied to numeric or floating point registers\n"); | |
562 | ret = -EINVAL; | |
563 | goto end; | |
564 | case REG_S64: | |
565 | break; | |
566 | } | |
567 | break; | |
568 | } | |
569 | ||
570 | case FILTER_OP_UNARY_PLUS_S64: | |
571 | case FILTER_OP_UNARY_MINUS_S64: | |
572 | case FILTER_OP_UNARY_NOT_S64: | |
573 | { | |
574 | if (!vstack_ax(stack)) { | |
575 | printk(KERN_WARNING "Empty stack\n"); | |
576 | ret = -EINVAL; | |
577 | goto end; | |
578 | } | |
579 | if (vstack_ax(stack)->type != REG_S64) { | |
580 | printk(KERN_WARNING "Invalid register type\n"); | |
581 | ret = -EINVAL; | |
582 | goto end; | |
583 | } | |
584 | break; | |
585 | } | |
586 | ||
587 | /* logical */ | |
588 | case FILTER_OP_AND: | |
589 | case FILTER_OP_OR: | |
590 | { | |
591 | struct logical_op *insn = (struct logical_op *) pc; | |
592 | ||
593 | if (!vstack_ax(stack)) { | |
594 | printk(KERN_WARNING "Empty stack\n"); | |
595 | ret = -EINVAL; | |
596 | goto end; | |
597 | } | |
598 | if (vstack_ax(stack)->type != REG_S64) { | |
599 | printk(KERN_WARNING "Logical comparator expects S64 register\n"); | |
600 | ret = -EINVAL; | |
601 | goto end; | |
602 | } | |
603 | ||
604 | dbg_printk("Validate jumping to bytecode offset %u\n", | |
605 | (unsigned int) insn->skip_offset); | |
606 | if (unlikely(start_pc + insn->skip_offset <= pc)) { | |
607 | printk(KERN_WARNING "Loops are not allowed in bytecode\n"); | |
608 | ret = -EINVAL; | |
609 | goto end; | |
610 | } | |
611 | break; | |
612 | } | |
613 | ||
614 | /* load field ref */ | |
615 | case FILTER_OP_LOAD_FIELD_REF: | |
616 | { | |
617 | printk(KERN_WARNING "Unknown field ref type\n"); | |
618 | ret = -EINVAL; | |
619 | goto end; | |
620 | } | |
621 | case FILTER_OP_LOAD_FIELD_REF_STRING: | |
622 | case FILTER_OP_LOAD_FIELD_REF_SEQUENCE: | |
f127e61e MD |
623 | case FILTER_OP_LOAD_FIELD_REF_USER_STRING: |
624 | case FILTER_OP_LOAD_FIELD_REF_USER_SEQUENCE: | |
07dfc1d0 MD |
625 | { |
626 | struct load_op *insn = (struct load_op *) pc; | |
627 | struct field_ref *ref = (struct field_ref *) insn->data; | |
628 | ||
629 | dbg_printk("Validate load field ref offset %u type string\n", | |
630 | ref->offset); | |
631 | break; | |
632 | } | |
633 | case FILTER_OP_LOAD_FIELD_REF_S64: | |
634 | { | |
635 | struct load_op *insn = (struct load_op *) pc; | |
636 | struct field_ref *ref = (struct field_ref *) insn->data; | |
637 | ||
638 | dbg_printk("Validate load field ref offset %u type s64\n", | |
639 | ref->offset); | |
640 | break; | |
641 | } | |
642 | ||
643 | /* load from immediate operand */ | |
644 | case FILTER_OP_LOAD_STRING: | |
645 | { | |
646 | break; | |
647 | } | |
648 | ||
649 | case FILTER_OP_LOAD_S64: | |
650 | { | |
651 | break; | |
652 | } | |
653 | ||
654 | case FILTER_OP_CAST_TO_S64: | |
655 | { | |
656 | struct cast_op *insn = (struct cast_op *) pc; | |
657 | ||
658 | if (!vstack_ax(stack)) { | |
659 | printk(KERN_WARNING "Empty stack\n"); | |
660 | ret = -EINVAL; | |
661 | goto end; | |
662 | } | |
663 | switch (vstack_ax(stack)->type) { | |
664 | default: | |
665 | case REG_DOUBLE: | |
666 | printk(KERN_WARNING "unknown register type\n"); | |
667 | ret = -EINVAL; | |
668 | goto end; | |
669 | ||
670 | case REG_STRING: | |
671 | printk(KERN_WARNING "Cast op can only be applied to numeric or floating point registers\n"); | |
672 | ret = -EINVAL; | |
673 | goto end; | |
674 | case REG_S64: | |
675 | break; | |
676 | } | |
677 | if (insn->op == FILTER_OP_CAST_DOUBLE_TO_S64) { | |
678 | if (vstack_ax(stack)->type != REG_DOUBLE) { | |
679 | printk(KERN_WARNING "Cast expects double\n"); | |
680 | ret = -EINVAL; | |
681 | goto end; | |
682 | } | |
683 | } | |
684 | break; | |
685 | } | |
686 | case FILTER_OP_CAST_NOP: | |
687 | { | |
688 | break; | |
689 | } | |
690 | ||
691 | /* get context ref */ | |
692 | case FILTER_OP_GET_CONTEXT_REF: | |
693 | { | |
694 | printk(KERN_WARNING "Unknown get context ref type\n"); | |
695 | ret = -EINVAL; | |
696 | goto end; | |
697 | } | |
698 | case FILTER_OP_GET_CONTEXT_REF_STRING: | |
699 | { | |
700 | struct load_op *insn = (struct load_op *) pc; | |
701 | struct field_ref *ref = (struct field_ref *) insn->data; | |
702 | ||
703 | dbg_printk("Validate get context ref offset %u type string\n", | |
704 | ref->offset); | |
705 | break; | |
706 | } | |
707 | case FILTER_OP_GET_CONTEXT_REF_S64: | |
708 | { | |
709 | struct load_op *insn = (struct load_op *) pc; | |
710 | struct field_ref *ref = (struct field_ref *) insn->data; | |
711 | ||
712 | dbg_printk("Validate get context ref offset %u type s64\n", | |
713 | ref->offset); | |
714 | break; | |
715 | } | |
716 | ||
717 | } | |
718 | end: | |
719 | return ret; | |
720 | } | |
721 | ||
722 | /* | |
723 | * Return value: | |
724 | * 0: success | |
725 | * <0: error | |
726 | */ | |
727 | static | |
728 | int validate_instruction_all_contexts(struct bytecode_runtime *bytecode, | |
729 | struct mp_table *mp_table, | |
730 | struct vstack *stack, | |
7962cb86 MD |
731 | char *start_pc, |
732 | char *pc) | |
07dfc1d0 MD |
733 | { |
734 | int ret, found = 0; | |
735 | unsigned long target_pc = pc - start_pc; | |
736 | unsigned long hash; | |
737 | struct hlist_head *head; | |
738 | struct mp_node *mp_node; | |
739 | ||
740 | /* Validate the context resulting from the previous instruction */ | |
741 | ret = validate_instruction_context(bytecode, stack, start_pc, pc); | |
742 | if (ret) | |
743 | return ret; | |
744 | ||
745 | /* Validate merge points */ | |
746 | hash = jhash_1word(target_pc, 0); | |
747 | head = &mp_table->mp_head[hash & (MERGE_POINT_TABLE_SIZE - 1)]; | |
d216ecae | 748 | lttng_hlist_for_each_entry(mp_node, head, node) { |
07dfc1d0 MD |
749 | if (lttng_hash_match(mp_node, target_pc)) { |
750 | found = 1; | |
751 | break; | |
752 | } | |
753 | } | |
754 | if (found) { | |
755 | dbg_printk("Filter: validate merge point at offset %lu\n", | |
756 | target_pc); | |
757 | if (merge_points_compare(stack, &mp_node->stack)) { | |
758 | printk(KERN_WARNING "Merge points differ for offset %lu\n", | |
759 | target_pc); | |
760 | return -EINVAL; | |
761 | } | |
762 | /* Once validated, we can remove the merge point */ | |
763 | dbg_printk("Filter: remove merge point at offset %lu\n", | |
764 | target_pc); | |
765 | hlist_del(&mp_node->node); | |
766 | } | |
767 | return 0; | |
768 | } | |
769 | ||
770 | /* | |
771 | * Return value: | |
772 | * >0: going to next insn. | |
773 | * 0: success, stop iteration. | |
774 | * <0: error | |
775 | */ | |
776 | static | |
777 | int exec_insn(struct bytecode_runtime *bytecode, | |
778 | struct mp_table *mp_table, | |
779 | struct vstack *stack, | |
7962cb86 MD |
780 | char **_next_pc, |
781 | char *pc) | |
07dfc1d0 MD |
782 | { |
783 | int ret = 1; | |
7962cb86 | 784 | char *next_pc = *_next_pc; |
07dfc1d0 MD |
785 | |
786 | switch (*(filter_opcode_t *) pc) { | |
787 | case FILTER_OP_UNKNOWN: | |
788 | default: | |
789 | { | |
790 | printk(KERN_WARNING "unknown bytecode op %u\n", | |
791 | (unsigned int) *(filter_opcode_t *) pc); | |
792 | ret = -EINVAL; | |
793 | goto end; | |
794 | } | |
795 | ||
796 | case FILTER_OP_RETURN: | |
797 | { | |
798 | if (!vstack_ax(stack)) { | |
799 | printk(KERN_WARNING "Empty stack\n"); | |
800 | ret = -EINVAL; | |
801 | goto end; | |
802 | } | |
803 | ret = 0; | |
804 | goto end; | |
805 | } | |
806 | ||
807 | /* binary */ | |
808 | case FILTER_OP_MUL: | |
809 | case FILTER_OP_DIV: | |
810 | case FILTER_OP_MOD: | |
811 | case FILTER_OP_PLUS: | |
812 | case FILTER_OP_MINUS: | |
813 | case FILTER_OP_RSHIFT: | |
814 | case FILTER_OP_LSHIFT: | |
815 | case FILTER_OP_BIN_AND: | |
816 | case FILTER_OP_BIN_OR: | |
817 | case FILTER_OP_BIN_XOR: | |
818 | /* Floating point */ | |
819 | case FILTER_OP_EQ_DOUBLE: | |
820 | case FILTER_OP_NE_DOUBLE: | |
821 | case FILTER_OP_GT_DOUBLE: | |
822 | case FILTER_OP_LT_DOUBLE: | |
823 | case FILTER_OP_GE_DOUBLE: | |
824 | case FILTER_OP_LE_DOUBLE: | |
825 | case FILTER_OP_EQ_DOUBLE_S64: | |
826 | case FILTER_OP_NE_DOUBLE_S64: | |
827 | case FILTER_OP_GT_DOUBLE_S64: | |
828 | case FILTER_OP_LT_DOUBLE_S64: | |
829 | case FILTER_OP_GE_DOUBLE_S64: | |
830 | case FILTER_OP_LE_DOUBLE_S64: | |
831 | case FILTER_OP_EQ_S64_DOUBLE: | |
832 | case FILTER_OP_NE_S64_DOUBLE: | |
833 | case FILTER_OP_GT_S64_DOUBLE: | |
834 | case FILTER_OP_LT_S64_DOUBLE: | |
835 | case FILTER_OP_GE_S64_DOUBLE: | |
836 | case FILTER_OP_LE_S64_DOUBLE: | |
837 | case FILTER_OP_UNARY_PLUS_DOUBLE: | |
838 | case FILTER_OP_UNARY_MINUS_DOUBLE: | |
839 | case FILTER_OP_UNARY_NOT_DOUBLE: | |
840 | case FILTER_OP_LOAD_FIELD_REF_DOUBLE: | |
841 | case FILTER_OP_GET_CONTEXT_REF_DOUBLE: | |
842 | case FILTER_OP_LOAD_DOUBLE: | |
843 | case FILTER_OP_CAST_DOUBLE_TO_S64: | |
844 | { | |
845 | printk(KERN_WARNING "unsupported bytecode op %u\n", | |
846 | (unsigned int) *(filter_opcode_t *) pc); | |
847 | ret = -EINVAL; | |
848 | goto end; | |
849 | } | |
850 | ||
851 | case FILTER_OP_EQ: | |
852 | case FILTER_OP_NE: | |
853 | case FILTER_OP_GT: | |
854 | case FILTER_OP_LT: | |
855 | case FILTER_OP_GE: | |
856 | case FILTER_OP_LE: | |
857 | case FILTER_OP_EQ_STRING: | |
858 | case FILTER_OP_NE_STRING: | |
859 | case FILTER_OP_GT_STRING: | |
860 | case FILTER_OP_LT_STRING: | |
861 | case FILTER_OP_GE_STRING: | |
862 | case FILTER_OP_LE_STRING: | |
863 | case FILTER_OP_EQ_S64: | |
864 | case FILTER_OP_NE_S64: | |
865 | case FILTER_OP_GT_S64: | |
866 | case FILTER_OP_LT_S64: | |
867 | case FILTER_OP_GE_S64: | |
868 | case FILTER_OP_LE_S64: | |
869 | { | |
870 | /* Pop 2, push 1 */ | |
871 | if (vstack_pop(stack)) { | |
872 | ret = -EINVAL; | |
873 | goto end; | |
874 | } | |
875 | if (!vstack_ax(stack)) { | |
876 | printk(KERN_WARNING "Empty stack\n"); | |
877 | ret = -EINVAL; | |
878 | goto end; | |
879 | } | |
880 | vstack_ax(stack)->type = REG_S64; | |
881 | next_pc += sizeof(struct binary_op); | |
882 | break; | |
883 | } | |
884 | ||
885 | /* unary */ | |
886 | case FILTER_OP_UNARY_PLUS: | |
887 | case FILTER_OP_UNARY_MINUS: | |
888 | case FILTER_OP_UNARY_NOT: | |
889 | case FILTER_OP_UNARY_PLUS_S64: | |
890 | case FILTER_OP_UNARY_MINUS_S64: | |
891 | case FILTER_OP_UNARY_NOT_S64: | |
892 | { | |
893 | /* Pop 1, push 1 */ | |
894 | if (!vstack_ax(stack)) { | |
895 | printk(KERN_WARNING "Empty stack\n"); | |
896 | ret = -EINVAL; | |
897 | goto end; | |
898 | } | |
899 | vstack_ax(stack)->type = REG_S64; | |
900 | next_pc += sizeof(struct unary_op); | |
901 | break; | |
902 | } | |
903 | ||
904 | /* logical */ | |
905 | case FILTER_OP_AND: | |
906 | case FILTER_OP_OR: | |
907 | { | |
908 | struct logical_op *insn = (struct logical_op *) pc; | |
909 | int merge_ret; | |
910 | ||
911 | /* Add merge point to table */ | |
912 | merge_ret = merge_point_add_check(mp_table, | |
913 | insn->skip_offset, stack); | |
914 | if (merge_ret) { | |
915 | ret = merge_ret; | |
916 | goto end; | |
917 | } | |
918 | /* Continue to next instruction */ | |
919 | /* Pop 1 when jump not taken */ | |
920 | if (vstack_pop(stack)) { | |
921 | ret = -EINVAL; | |
922 | goto end; | |
923 | } | |
924 | next_pc += sizeof(struct logical_op); | |
925 | break; | |
926 | } | |
927 | ||
928 | /* load field ref */ | |
929 | case FILTER_OP_LOAD_FIELD_REF: | |
930 | { | |
931 | printk(KERN_WARNING "Unknown field ref type\n"); | |
932 | ret = -EINVAL; | |
933 | goto end; | |
934 | } | |
935 | /* get context ref */ | |
936 | case FILTER_OP_GET_CONTEXT_REF: | |
937 | { | |
938 | printk(KERN_WARNING "Unknown get context ref type\n"); | |
939 | ret = -EINVAL; | |
940 | goto end; | |
941 | } | |
942 | case FILTER_OP_LOAD_FIELD_REF_STRING: | |
943 | case FILTER_OP_LOAD_FIELD_REF_SEQUENCE: | |
944 | case FILTER_OP_GET_CONTEXT_REF_STRING: | |
f127e61e MD |
945 | case FILTER_OP_LOAD_FIELD_REF_USER_STRING: |
946 | case FILTER_OP_LOAD_FIELD_REF_USER_SEQUENCE: | |
07dfc1d0 MD |
947 | { |
948 | if (vstack_push(stack)) { | |
949 | ret = -EINVAL; | |
950 | goto end; | |
951 | } | |
952 | vstack_ax(stack)->type = REG_STRING; | |
953 | next_pc += sizeof(struct load_op) + sizeof(struct field_ref); | |
954 | break; | |
955 | } | |
956 | case FILTER_OP_LOAD_FIELD_REF_S64: | |
957 | case FILTER_OP_GET_CONTEXT_REF_S64: | |
958 | { | |
959 | if (vstack_push(stack)) { | |
960 | ret = -EINVAL; | |
961 | goto end; | |
962 | } | |
963 | vstack_ax(stack)->type = REG_S64; | |
964 | next_pc += sizeof(struct load_op) + sizeof(struct field_ref); | |
965 | break; | |
966 | } | |
967 | ||
968 | /* load from immediate operand */ | |
969 | case FILTER_OP_LOAD_STRING: | |
970 | { | |
971 | struct load_op *insn = (struct load_op *) pc; | |
972 | ||
973 | if (vstack_push(stack)) { | |
974 | ret = -EINVAL; | |
975 | goto end; | |
976 | } | |
977 | vstack_ax(stack)->type = REG_STRING; | |
978 | next_pc += sizeof(struct load_op) + strlen(insn->data) + 1; | |
979 | break; | |
980 | } | |
981 | ||
982 | case FILTER_OP_LOAD_S64: | |
983 | { | |
984 | if (vstack_push(stack)) { | |
985 | ret = -EINVAL; | |
986 | goto end; | |
987 | } | |
988 | vstack_ax(stack)->type = REG_S64; | |
989 | next_pc += sizeof(struct load_op) | |
990 | + sizeof(struct literal_numeric); | |
991 | break; | |
992 | } | |
993 | ||
994 | case FILTER_OP_CAST_TO_S64: | |
995 | { | |
996 | /* Pop 1, push 1 */ | |
997 | if (!vstack_ax(stack)) { | |
998 | printk(KERN_WARNING "Empty stack\n"); | |
999 | ret = -EINVAL; | |
1000 | goto end; | |
1001 | } | |
1002 | vstack_ax(stack)->type = REG_S64; | |
1003 | next_pc += sizeof(struct cast_op); | |
1004 | break; | |
1005 | } | |
1006 | case FILTER_OP_CAST_NOP: | |
1007 | { | |
1008 | next_pc += sizeof(struct cast_op); | |
1009 | break; | |
1010 | } | |
1011 | ||
1012 | } | |
1013 | end: | |
1014 | *_next_pc = next_pc; | |
1015 | return ret; | |
1016 | } | |
1017 | ||
1018 | /* | |
1019 | * Never called concurrently (hash seed is shared). | |
1020 | */ | |
1021 | int lttng_filter_validate_bytecode(struct bytecode_runtime *bytecode) | |
1022 | { | |
1023 | struct mp_table *mp_table; | |
7962cb86 | 1024 | char *pc, *next_pc, *start_pc; |
07dfc1d0 MD |
1025 | int ret = -EINVAL; |
1026 | struct vstack stack; | |
1027 | ||
1028 | vstack_init(&stack); | |
1029 | ||
1030 | mp_table = kzalloc(sizeof(*mp_table), GFP_KERNEL); | |
1031 | if (!mp_table) { | |
1032 | printk(KERN_WARNING "Error allocating hash table for bytecode validation\n"); | |
1033 | return -ENOMEM; | |
1034 | } | |
1035 | start_pc = &bytecode->data[0]; | |
1036 | for (pc = next_pc = start_pc; pc - start_pc < bytecode->len; | |
1037 | pc = next_pc) { | |
1038 | ret = bytecode_validate_overflow(bytecode, start_pc, pc); | |
1039 | if (ret != 0) { | |
1040 | if (ret == -ERANGE) | |
1041 | printk(KERN_WARNING "filter bytecode overflow\n"); | |
1042 | goto end; | |
1043 | } | |
1044 | dbg_printk("Validating op %s (%u)\n", | |
1045 | lttng_filter_print_op((unsigned int) *(filter_opcode_t *) pc), | |
1046 | (unsigned int) *(filter_opcode_t *) pc); | |
1047 | ||
1048 | /* | |
1049 | * For each instruction, validate the current context | |
1050 | * (traversal of entire execution flow), and validate | |
1051 | * all merge points targeting this instruction. | |
1052 | */ | |
1053 | ret = validate_instruction_all_contexts(bytecode, mp_table, | |
1054 | &stack, start_pc, pc); | |
1055 | if (ret) | |
1056 | goto end; | |
1057 | ret = exec_insn(bytecode, mp_table, &stack, &next_pc, pc); | |
1058 | if (ret <= 0) | |
1059 | goto end; | |
1060 | } | |
1061 | end: | |
1062 | if (delete_all_nodes(mp_table)) { | |
1063 | if (!ret) { | |
1064 | printk(KERN_WARNING "Unexpected merge points\n"); | |
1065 | ret = -EINVAL; | |
1066 | } | |
1067 | } | |
1068 | kfree(mp_table); | |
1069 | return ret; | |
1070 | } |