Commit | Line | Data |
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97b58163 MD |
1 | /* |
2 | * lttng-filter-validator.c | |
3 | * | |
4 | * LTTng UST filter bytecode validator. | |
5 | * | |
6 | * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
7 | * | |
8 | * This library is free software; you can redistribute it and/or | |
9 | * modify it under the terms of the GNU Lesser General Public | |
10 | * License as published by the Free Software Foundation; only | |
11 | * version 2.1 of the License. | |
12 | * | |
13 | * This library is distributed in the hope that it will be useful, | |
14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
16 | * Lesser General Public License for more details. | |
17 | * | |
18 | * You should have received a copy of the GNU Lesser General Public | |
19 | * License along with this library; if not, write to the Free Software | |
20 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
21 | */ | |
22 | ||
bf956ec0 MD |
23 | #define _LGPL_SOURCE |
24 | #include <urcu-bp.h> | |
25 | #include <time.h> | |
97b58163 MD |
26 | #include "lttng-filter.h" |
27 | ||
bf956ec0 MD |
28 | #include <urcu/rculfhash.h> |
29 | #include "lttng-hash-helper.h" | |
30 | ||
0305960f MD |
31 | /* |
32 | * Number of merge points for hash table size. Hash table initialized to | |
33 | * that size, and we do not resize, because we do not want to trigger | |
34 | * RCU worker thread execution: fall-back on linear traversal if number | |
35 | * of merge points exceeds this value. | |
36 | */ | |
37 | #define DEFAULT_NR_MERGE_POINTS 128 | |
38 | #define MIN_NR_BUCKETS 128 | |
39 | #define MAX_NR_BUCKETS 128 | |
40 | ||
bf956ec0 MD |
41 | /* merge point table node */ |
42 | struct lfht_mp_node { | |
43 | struct cds_lfht_node node; | |
44 | ||
45 | /* Context at merge point */ | |
0305960f | 46 | struct vstack stack; |
bf956ec0 MD |
47 | unsigned long target_pc; |
48 | }; | |
49 | ||
50 | static unsigned long lttng_hash_seed; | |
51 | static unsigned int lttng_hash_seed_ready; | |
52 | ||
53 | static | |
54 | int lttng_hash_match(struct cds_lfht_node *node, const void *key) | |
55 | { | |
56 | struct lfht_mp_node *mp_node = | |
57 | caa_container_of(node, struct lfht_mp_node, node); | |
58 | unsigned long key_pc = (unsigned long) key; | |
59 | ||
60 | if (mp_node->target_pc == key_pc) | |
61 | return 1; | |
62 | else | |
63 | return 0; | |
64 | } | |
65 | ||
66 | static | |
67 | int merge_point_add(struct cds_lfht *ht, unsigned long target_pc, | |
0305960f | 68 | const struct vstack *stack) |
bf956ec0 MD |
69 | { |
70 | struct lfht_mp_node *node; | |
71 | unsigned long hash = lttng_hash_mix((const void *) target_pc, | |
72 | sizeof(target_pc), | |
73 | lttng_hash_seed); | |
74 | ||
75 | dbg_printf("Filter: adding merge point at offset %lu, hash %lu\n", | |
76 | target_pc, hash); | |
77 | node = zmalloc(sizeof(struct lfht_mp_node)); | |
78 | if (!node) | |
79 | return -ENOMEM; | |
80 | node->target_pc = target_pc; | |
0305960f | 81 | memcpy(&node->stack, stack, sizeof(node->stack)); |
bf956ec0 MD |
82 | cds_lfht_add(ht, hash, &node->node); |
83 | return 0; | |
84 | } | |
85 | ||
86 | /* | |
0305960f | 87 | * Binary comparators use top of stack and top of stack -1. |
bf956ec0 | 88 | */ |
97b58163 | 89 | static |
0305960f | 90 | int bin_op_compare_check(struct vstack *stack, const char *str) |
97b58163 | 91 | { |
0305960f MD |
92 | if (unlikely(!vstack_ax(stack) || !vstack_bx(stack))) |
93 | goto error_unknown; | |
94 | ||
95 | switch (vstack_ax(stack)->type) { | |
97b58163 MD |
96 | default: |
97 | goto error_unknown; | |
98 | ||
99 | case REG_STRING: | |
0305960f | 100 | switch (vstack_bx(stack)->type) { |
97b58163 MD |
101 | default: |
102 | goto error_unknown; | |
103 | ||
104 | case REG_STRING: | |
105 | break; | |
106 | case REG_S64: | |
107 | case REG_DOUBLE: | |
108 | goto error_mismatch; | |
109 | } | |
110 | break; | |
111 | case REG_S64: | |
112 | case REG_DOUBLE: | |
0305960f | 113 | switch (vstack_bx(stack)->type) { |
97b58163 MD |
114 | default: |
115 | goto error_unknown; | |
116 | ||
117 | case REG_STRING: | |
118 | goto error_mismatch; | |
119 | ||
120 | case REG_S64: | |
121 | case REG_DOUBLE: | |
122 | break; | |
123 | } | |
124 | break; | |
125 | } | |
126 | return 0; | |
127 | ||
128 | error_unknown: | |
97b58163 | 129 | return -EINVAL; |
0305960f | 130 | |
97b58163 MD |
131 | error_mismatch: |
132 | ERR("type mismatch for '%s' binary operator\n", str); | |
133 | return -EINVAL; | |
134 | } | |
135 | ||
136 | /* | |
137 | * Validate bytecode range overflow within the validation pass. | |
138 | * Called for each instruction encountered. | |
139 | */ | |
140 | static | |
141 | int bytecode_validate_overflow(struct bytecode_runtime *bytecode, | |
bf956ec0 | 142 | void *start_pc, void *pc) |
97b58163 MD |
143 | { |
144 | int ret = 0; | |
145 | ||
146 | switch (*(filter_opcode_t *) pc) { | |
147 | case FILTER_OP_UNKNOWN: | |
148 | default: | |
149 | { | |
150 | ERR("unknown bytecode op %u\n", | |
151 | (unsigned int) *(filter_opcode_t *) pc); | |
152 | ret = -EINVAL; | |
153 | break; | |
154 | } | |
155 | ||
156 | case FILTER_OP_RETURN: | |
157 | { | |
158 | if (unlikely(pc + sizeof(struct return_op) | |
159 | > start_pc + bytecode->len)) { | |
160 | ret = -EINVAL; | |
161 | } | |
162 | break; | |
163 | } | |
164 | ||
165 | /* binary */ | |
166 | case FILTER_OP_MUL: | |
167 | case FILTER_OP_DIV: | |
168 | case FILTER_OP_MOD: | |
169 | case FILTER_OP_PLUS: | |
170 | case FILTER_OP_MINUS: | |
171 | case FILTER_OP_RSHIFT: | |
172 | case FILTER_OP_LSHIFT: | |
173 | case FILTER_OP_BIN_AND: | |
174 | case FILTER_OP_BIN_OR: | |
175 | case FILTER_OP_BIN_XOR: | |
176 | { | |
177 | ERR("unsupported bytecode op %u\n", | |
178 | (unsigned int) *(filter_opcode_t *) pc); | |
179 | ret = -EINVAL; | |
180 | break; | |
181 | } | |
182 | ||
183 | case FILTER_OP_EQ: | |
184 | case FILTER_OP_NE: | |
185 | case FILTER_OP_GT: | |
186 | case FILTER_OP_LT: | |
187 | case FILTER_OP_GE: | |
188 | case FILTER_OP_LE: | |
189 | case FILTER_OP_EQ_STRING: | |
190 | case FILTER_OP_NE_STRING: | |
191 | case FILTER_OP_GT_STRING: | |
192 | case FILTER_OP_LT_STRING: | |
193 | case FILTER_OP_GE_STRING: | |
194 | case FILTER_OP_LE_STRING: | |
195 | case FILTER_OP_EQ_S64: | |
196 | case FILTER_OP_NE_S64: | |
197 | case FILTER_OP_GT_S64: | |
198 | case FILTER_OP_LT_S64: | |
199 | case FILTER_OP_GE_S64: | |
200 | case FILTER_OP_LE_S64: | |
201 | case FILTER_OP_EQ_DOUBLE: | |
202 | case FILTER_OP_NE_DOUBLE: | |
203 | case FILTER_OP_GT_DOUBLE: | |
204 | case FILTER_OP_LT_DOUBLE: | |
205 | case FILTER_OP_GE_DOUBLE: | |
206 | case FILTER_OP_LE_DOUBLE: | |
207 | { | |
208 | if (unlikely(pc + sizeof(struct binary_op) | |
209 | > start_pc + bytecode->len)) { | |
210 | ret = -EINVAL; | |
211 | } | |
212 | break; | |
213 | } | |
214 | ||
215 | /* unary */ | |
216 | case FILTER_OP_UNARY_PLUS: | |
217 | case FILTER_OP_UNARY_MINUS: | |
218 | case FILTER_OP_UNARY_NOT: | |
219 | case FILTER_OP_UNARY_PLUS_S64: | |
220 | case FILTER_OP_UNARY_MINUS_S64: | |
221 | case FILTER_OP_UNARY_NOT_S64: | |
222 | case FILTER_OP_UNARY_PLUS_DOUBLE: | |
223 | case FILTER_OP_UNARY_MINUS_DOUBLE: | |
224 | case FILTER_OP_UNARY_NOT_DOUBLE: | |
225 | { | |
226 | if (unlikely(pc + sizeof(struct unary_op) | |
227 | > start_pc + bytecode->len)) { | |
228 | ret = -EINVAL; | |
229 | } | |
230 | break; | |
231 | } | |
232 | ||
233 | /* logical */ | |
234 | case FILTER_OP_AND: | |
235 | case FILTER_OP_OR: | |
236 | { | |
237 | if (unlikely(pc + sizeof(struct logical_op) | |
238 | > start_pc + bytecode->len)) { | |
239 | ret = -EINVAL; | |
240 | } | |
241 | break; | |
242 | } | |
243 | ||
244 | /* load */ | |
245 | case FILTER_OP_LOAD_FIELD_REF: | |
246 | { | |
247 | ERR("Unknown field ref type\n"); | |
248 | ret = -EINVAL; | |
249 | break; | |
250 | } | |
251 | case FILTER_OP_LOAD_FIELD_REF_STRING: | |
252 | case FILTER_OP_LOAD_FIELD_REF_SEQUENCE: | |
253 | case FILTER_OP_LOAD_FIELD_REF_S64: | |
254 | case FILTER_OP_LOAD_FIELD_REF_DOUBLE: | |
255 | { | |
256 | if (unlikely(pc + sizeof(struct load_op) + sizeof(struct field_ref) | |
257 | > start_pc + bytecode->len)) { | |
258 | ret = -EINVAL; | |
259 | } | |
260 | break; | |
261 | } | |
262 | ||
263 | case FILTER_OP_LOAD_STRING: | |
264 | { | |
265 | struct load_op *insn = (struct load_op *) pc; | |
266 | uint32_t str_len, maxlen; | |
267 | ||
268 | if (unlikely(pc + sizeof(struct load_op) | |
269 | > start_pc + bytecode->len)) { | |
270 | ret = -EINVAL; | |
271 | break; | |
272 | } | |
273 | ||
274 | maxlen = start_pc + bytecode->len - pc - sizeof(struct load_op); | |
275 | str_len = strnlen(insn->data, maxlen); | |
276 | if (unlikely(str_len >= maxlen)) { | |
277 | /* Final '\0' not found within range */ | |
278 | ret = -EINVAL; | |
279 | } | |
280 | break; | |
281 | } | |
282 | ||
283 | case FILTER_OP_LOAD_S64: | |
284 | { | |
285 | if (unlikely(pc + sizeof(struct load_op) + sizeof(struct literal_numeric) | |
286 | > start_pc + bytecode->len)) { | |
287 | ret = -EINVAL; | |
288 | } | |
289 | break; | |
290 | } | |
291 | ||
292 | case FILTER_OP_LOAD_DOUBLE: | |
293 | { | |
294 | if (unlikely(pc + sizeof(struct load_op) + sizeof(struct literal_double) | |
295 | > start_pc + bytecode->len)) { | |
296 | ret = -EINVAL; | |
297 | } | |
298 | break; | |
299 | } | |
300 | ||
301 | case FILTER_OP_CAST_TO_S64: | |
302 | case FILTER_OP_CAST_DOUBLE_TO_S64: | |
303 | case FILTER_OP_CAST_NOP: | |
304 | { | |
305 | if (unlikely(pc + sizeof(struct cast_op) | |
306 | > start_pc + bytecode->len)) { | |
307 | ret = -EINVAL; | |
308 | } | |
309 | break; | |
310 | } | |
311 | } | |
312 | ||
313 | return ret; | |
314 | } | |
315 | ||
bf956ec0 MD |
316 | static |
317 | unsigned long delete_all_nodes(struct cds_lfht *ht) | |
97b58163 | 318 | { |
bf956ec0 MD |
319 | struct cds_lfht_iter iter; |
320 | struct lfht_mp_node *node; | |
321 | unsigned long nr_nodes = 0; | |
97b58163 | 322 | |
bf956ec0 MD |
323 | cds_lfht_for_each_entry(ht, &iter, node, node) { |
324 | int ret; | |
325 | ||
326 | ret = cds_lfht_del(ht, cds_lfht_iter_get_node(&iter)); | |
327 | assert(!ret); | |
328 | /* note: this hash table is never used concurrently */ | |
329 | free(node); | |
330 | nr_nodes++; | |
97b58163 | 331 | } |
bf956ec0 MD |
332 | return nr_nodes; |
333 | } | |
97b58163 | 334 | |
bf956ec0 MD |
335 | /* |
336 | * Return value: | |
337 | * 0: success | |
338 | * <0: error | |
339 | */ | |
340 | static | |
341 | int validate_instruction_context(struct bytecode_runtime *bytecode, | |
0305960f | 342 | struct vstack *stack, |
bf956ec0 MD |
343 | void *start_pc, |
344 | void *pc) | |
345 | { | |
346 | int ret = 0; | |
347 | ||
348 | switch (*(filter_opcode_t *) pc) { | |
349 | case FILTER_OP_UNKNOWN: | |
350 | default: | |
351 | { | |
352 | ERR("unknown bytecode op %u\n", | |
97b58163 | 353 | (unsigned int) *(filter_opcode_t *) pc); |
bf956ec0 MD |
354 | ret = -EINVAL; |
355 | goto end; | |
356 | } | |
357 | ||
358 | case FILTER_OP_RETURN: | |
359 | { | |
360 | goto end; | |
361 | } | |
362 | ||
363 | /* binary */ | |
364 | case FILTER_OP_MUL: | |
365 | case FILTER_OP_DIV: | |
366 | case FILTER_OP_MOD: | |
367 | case FILTER_OP_PLUS: | |
368 | case FILTER_OP_MINUS: | |
369 | case FILTER_OP_RSHIFT: | |
370 | case FILTER_OP_LSHIFT: | |
371 | case FILTER_OP_BIN_AND: | |
372 | case FILTER_OP_BIN_OR: | |
373 | case FILTER_OP_BIN_XOR: | |
374 | { | |
375 | ERR("unsupported bytecode op %u\n", | |
376 | (unsigned int) *(filter_opcode_t *) pc); | |
377 | ret = -EINVAL; | |
378 | goto end; | |
379 | } | |
97b58163 | 380 | |
bf956ec0 MD |
381 | case FILTER_OP_EQ: |
382 | { | |
0305960f | 383 | ret = bin_op_compare_check(stack, "=="); |
bf956ec0 MD |
384 | if (ret) |
385 | goto end; | |
386 | break; | |
387 | } | |
388 | case FILTER_OP_NE: | |
389 | { | |
0305960f | 390 | ret = bin_op_compare_check(stack, "!="); |
bf956ec0 MD |
391 | if (ret) |
392 | goto end; | |
393 | break; | |
394 | } | |
395 | case FILTER_OP_GT: | |
396 | { | |
0305960f | 397 | ret = bin_op_compare_check(stack, ">"); |
bf956ec0 MD |
398 | if (ret) |
399 | goto end; | |
400 | break; | |
401 | } | |
402 | case FILTER_OP_LT: | |
403 | { | |
0305960f | 404 | ret = bin_op_compare_check(stack, "<"); |
bf956ec0 MD |
405 | if (ret) |
406 | goto end; | |
407 | break; | |
408 | } | |
409 | case FILTER_OP_GE: | |
410 | { | |
0305960f | 411 | ret = bin_op_compare_check(stack, ">="); |
bf956ec0 MD |
412 | if (ret) |
413 | goto end; | |
414 | break; | |
415 | } | |
416 | case FILTER_OP_LE: | |
417 | { | |
0305960f | 418 | ret = bin_op_compare_check(stack, "<="); |
bf956ec0 | 419 | if (ret) |
97b58163 | 420 | goto end; |
bf956ec0 MD |
421 | break; |
422 | } | |
97b58163 | 423 | |
bf956ec0 MD |
424 | case FILTER_OP_EQ_STRING: |
425 | case FILTER_OP_NE_STRING: | |
426 | case FILTER_OP_GT_STRING: | |
427 | case FILTER_OP_LT_STRING: | |
428 | case FILTER_OP_GE_STRING: | |
429 | case FILTER_OP_LE_STRING: | |
430 | { | |
0305960f MD |
431 | if (!vstack_ax(stack) || !vstack_bx(stack)) { |
432 | ERR("Empty stack\n"); | |
433 | ret = -EINVAL; | |
434 | goto end; | |
435 | } | |
436 | if (vstack_ax(stack)->type != REG_STRING | |
437 | || vstack_bx(stack)->type != REG_STRING) { | |
bf956ec0 | 438 | ERR("Unexpected register type for string comparator\n"); |
97b58163 MD |
439 | ret = -EINVAL; |
440 | goto end; | |
97b58163 | 441 | } |
bf956ec0 MD |
442 | break; |
443 | } | |
97b58163 | 444 | |
bf956ec0 MD |
445 | case FILTER_OP_EQ_S64: |
446 | case FILTER_OP_NE_S64: | |
447 | case FILTER_OP_GT_S64: | |
448 | case FILTER_OP_LT_S64: | |
449 | case FILTER_OP_GE_S64: | |
450 | case FILTER_OP_LE_S64: | |
451 | { | |
0305960f MD |
452 | if (!vstack_ax(stack) || !vstack_bx(stack)) { |
453 | ERR("Empty stack\n"); | |
454 | ret = -EINVAL; | |
455 | goto end; | |
456 | } | |
457 | if (vstack_ax(stack)->type != REG_S64 | |
458 | || vstack_bx(stack)->type != REG_S64) { | |
bf956ec0 MD |
459 | ERR("Unexpected register type for s64 comparator\n"); |
460 | ret = -EINVAL; | |
461 | goto end; | |
97b58163 | 462 | } |
bf956ec0 MD |
463 | break; |
464 | } | |
97b58163 | 465 | |
bf956ec0 MD |
466 | case FILTER_OP_EQ_DOUBLE: |
467 | case FILTER_OP_NE_DOUBLE: | |
468 | case FILTER_OP_GT_DOUBLE: | |
469 | case FILTER_OP_LT_DOUBLE: | |
470 | case FILTER_OP_GE_DOUBLE: | |
471 | case FILTER_OP_LE_DOUBLE: | |
472 | { | |
0305960f MD |
473 | if (!vstack_ax(stack) || !vstack_bx(stack)) { |
474 | ERR("Empty stack\n"); | |
475 | ret = -EINVAL; | |
476 | goto end; | |
477 | } | |
478 | if ((vstack_ax(stack)->type != REG_DOUBLE && vstack_ax(stack)->type != REG_S64) | |
479 | || (vstack_bx(stack)-> type != REG_DOUBLE && vstack_bx(stack)->type != REG_S64)) { | |
bf956ec0 MD |
480 | ERR("Unexpected register type for double comparator\n"); |
481 | ret = -EINVAL; | |
482 | goto end; | |
97b58163 | 483 | } |
0305960f | 484 | if (vstack_ax(stack)->type != REG_DOUBLE && vstack_bx(stack)->type != REG_DOUBLE) { |
bf956ec0 MD |
485 | ERR("Double operator should have at least one double register\n"); |
486 | ret = -EINVAL; | |
487 | goto end; | |
97b58163 | 488 | } |
bf956ec0 MD |
489 | break; |
490 | } | |
97b58163 | 491 | |
bf956ec0 MD |
492 | /* unary */ |
493 | case FILTER_OP_UNARY_PLUS: | |
494 | case FILTER_OP_UNARY_MINUS: | |
495 | case FILTER_OP_UNARY_NOT: | |
496 | { | |
0305960f MD |
497 | if (!vstack_ax(stack)) { |
498 | ERR("Empty stack\n"); | |
bf956ec0 MD |
499 | ret = -EINVAL; |
500 | goto end; | |
501 | } | |
0305960f | 502 | switch (vstack_ax(stack)->type) { |
bf956ec0 MD |
503 | default: |
504 | ERR("unknown register type\n"); | |
505 | ret = -EINVAL; | |
506 | goto end; | |
97b58163 | 507 | |
bf956ec0 MD |
508 | case REG_STRING: |
509 | ERR("Unary op can only be applied to numeric or floating point registers\n"); | |
510 | ret = -EINVAL; | |
511 | goto end; | |
512 | case REG_S64: | |
513 | break; | |
514 | case REG_DOUBLE: | |
97b58163 MD |
515 | break; |
516 | } | |
bf956ec0 MD |
517 | break; |
518 | } | |
97b58163 | 519 | |
bf956ec0 MD |
520 | case FILTER_OP_UNARY_PLUS_S64: |
521 | case FILTER_OP_UNARY_MINUS_S64: | |
522 | case FILTER_OP_UNARY_NOT_S64: | |
523 | { | |
0305960f MD |
524 | if (!vstack_ax(stack)) { |
525 | ERR("Empty stack\n"); | |
bf956ec0 MD |
526 | ret = -EINVAL; |
527 | goto end; | |
528 | } | |
0305960f | 529 | if (vstack_ax(stack)->type != REG_S64) { |
bf956ec0 MD |
530 | ERR("Invalid register type\n"); |
531 | ret = -EINVAL; | |
532 | goto end; | |
97b58163 | 533 | } |
bf956ec0 MD |
534 | break; |
535 | } | |
97b58163 | 536 | |
bf956ec0 MD |
537 | case FILTER_OP_UNARY_PLUS_DOUBLE: |
538 | case FILTER_OP_UNARY_MINUS_DOUBLE: | |
539 | case FILTER_OP_UNARY_NOT_DOUBLE: | |
540 | { | |
0305960f MD |
541 | if (!vstack_ax(stack)) { |
542 | ERR("Empty stack\n"); | |
bf956ec0 MD |
543 | ret = -EINVAL; |
544 | goto end; | |
97b58163 | 545 | } |
0305960f | 546 | if (vstack_ax(stack)->type != REG_DOUBLE) { |
bf956ec0 MD |
547 | ERR("Invalid register type\n"); |
548 | ret = -EINVAL; | |
549 | goto end; | |
550 | } | |
551 | break; | |
552 | } | |
97b58163 | 553 | |
bf956ec0 MD |
554 | /* logical */ |
555 | case FILTER_OP_AND: | |
556 | case FILTER_OP_OR: | |
557 | { | |
558 | struct logical_op *insn = (struct logical_op *) pc; | |
97b58163 | 559 | |
0305960f MD |
560 | if (!vstack_ax(stack)) { |
561 | ERR("Empty stack\n"); | |
562 | ret = -EINVAL; | |
563 | goto end; | |
564 | } | |
565 | if (vstack_ax(stack)->type != REG_S64) { | |
bf956ec0 MD |
566 | ERR("Logical comparator expects S64 register\n"); |
567 | ret = -EINVAL; | |
568 | goto end; | |
97b58163 MD |
569 | } |
570 | ||
bf956ec0 MD |
571 | dbg_printf("Validate jumping to bytecode offset %u\n", |
572 | (unsigned int) insn->skip_offset); | |
573 | if (unlikely(start_pc + insn->skip_offset <= pc)) { | |
574 | ERR("Loops are not allowed in bytecode\n"); | |
97b58163 MD |
575 | ret = -EINVAL; |
576 | goto end; | |
577 | } | |
bf956ec0 MD |
578 | break; |
579 | } | |
97b58163 | 580 | |
bf956ec0 MD |
581 | /* load */ |
582 | case FILTER_OP_LOAD_FIELD_REF: | |
583 | { | |
584 | ERR("Unknown field ref type\n"); | |
585 | ret = -EINVAL; | |
586 | goto end; | |
587 | } | |
588 | case FILTER_OP_LOAD_FIELD_REF_STRING: | |
589 | case FILTER_OP_LOAD_FIELD_REF_SEQUENCE: | |
590 | { | |
591 | struct load_op *insn = (struct load_op *) pc; | |
592 | struct field_ref *ref = (struct field_ref *) insn->data; | |
593 | ||
bf956ec0 MD |
594 | dbg_printf("Validate load field ref offset %u type string\n", |
595 | ref->offset); | |
596 | break; | |
597 | } | |
598 | case FILTER_OP_LOAD_FIELD_REF_S64: | |
599 | { | |
600 | struct load_op *insn = (struct load_op *) pc; | |
601 | struct field_ref *ref = (struct field_ref *) insn->data; | |
97b58163 | 602 | |
bf956ec0 MD |
603 | dbg_printf("Validate load field ref offset %u type s64\n", |
604 | ref->offset); | |
605 | break; | |
606 | } | |
607 | case FILTER_OP_LOAD_FIELD_REF_DOUBLE: | |
608 | { | |
609 | struct load_op *insn = (struct load_op *) pc; | |
610 | struct field_ref *ref = (struct field_ref *) insn->data; | |
97b58163 | 611 | |
bf956ec0 MD |
612 | dbg_printf("Validate load field ref offset %u type double\n", |
613 | ref->offset); | |
614 | break; | |
615 | } | |
97b58163 | 616 | |
bf956ec0 MD |
617 | case FILTER_OP_LOAD_STRING: |
618 | { | |
bf956ec0 MD |
619 | break; |
620 | } | |
97b58163 | 621 | |
bf956ec0 MD |
622 | case FILTER_OP_LOAD_S64: |
623 | { | |
bf956ec0 MD |
624 | break; |
625 | } | |
97b58163 | 626 | |
bf956ec0 MD |
627 | case FILTER_OP_LOAD_DOUBLE: |
628 | { | |
bf956ec0 MD |
629 | break; |
630 | } | |
97b58163 | 631 | |
bf956ec0 MD |
632 | case FILTER_OP_CAST_TO_S64: |
633 | case FILTER_OP_CAST_DOUBLE_TO_S64: | |
634 | { | |
635 | struct cast_op *insn = (struct cast_op *) pc; | |
97b58163 | 636 | |
0305960f MD |
637 | if (!vstack_ax(stack)) { |
638 | ERR("Empty stack\n"); | |
bf956ec0 MD |
639 | ret = -EINVAL; |
640 | goto end; | |
641 | } | |
0305960f | 642 | switch (vstack_ax(stack)->type) { |
bf956ec0 MD |
643 | default: |
644 | ERR("unknown register type\n"); | |
645 | ret = -EINVAL; | |
646 | goto end; | |
97b58163 | 647 | |
bf956ec0 MD |
648 | case REG_STRING: |
649 | ERR("Cast op can only be applied to numeric or floating point registers\n"); | |
650 | ret = -EINVAL; | |
651 | goto end; | |
652 | case REG_S64: | |
653 | break; | |
654 | case REG_DOUBLE: | |
655 | break; | |
656 | } | |
657 | if (insn->op == FILTER_OP_CAST_DOUBLE_TO_S64) { | |
0305960f | 658 | if (vstack_ax(stack)->type != REG_DOUBLE) { |
bf956ec0 | 659 | ERR("Cast expects double\n"); |
97b58163 MD |
660 | ret = -EINVAL; |
661 | goto end; | |
97b58163 | 662 | } |
97b58163 | 663 | } |
bf956ec0 MD |
664 | break; |
665 | } | |
666 | case FILTER_OP_CAST_NOP: | |
667 | { | |
668 | break; | |
669 | } | |
670 | ||
671 | } | |
672 | end: | |
673 | return ret; | |
674 | } | |
675 | ||
676 | /* | |
677 | * Return value: | |
678 | * 0: success | |
679 | * <0: error | |
680 | */ | |
681 | static | |
682 | int validate_instruction_all_contexts(struct bytecode_runtime *bytecode, | |
683 | struct cds_lfht *merge_points, | |
0305960f | 684 | struct vstack *stack, |
bf956ec0 MD |
685 | void *start_pc, |
686 | void *pc) | |
687 | { | |
688 | int ret; | |
689 | unsigned long target_pc = pc - start_pc; | |
690 | struct cds_lfht_iter iter; | |
691 | struct cds_lfht_node *node; | |
692 | unsigned long hash; | |
693 | ||
694 | /* Validate the context resulting from the previous instruction */ | |
0305960f | 695 | ret = validate_instruction_context(bytecode, stack, start_pc, pc); |
bf956ec0 MD |
696 | if (ret) |
697 | return ret; | |
698 | ||
699 | /* Validate merge points */ | |
700 | hash = lttng_hash_mix((const void *) target_pc, sizeof(target_pc), | |
701 | lttng_hash_seed); | |
702 | cds_lfht_for_each_duplicate(merge_points, hash, lttng_hash_match, | |
703 | (const void *) target_pc, &iter, node) { | |
704 | struct lfht_mp_node *mp_node = | |
705 | caa_container_of(node, struct lfht_mp_node, node); | |
706 | ||
707 | dbg_printf("Filter: validate merge point at offset %lu\n", | |
708 | target_pc); | |
0305960f | 709 | ret = validate_instruction_context(bytecode, &mp_node->stack, |
bf956ec0 MD |
710 | start_pc, pc); |
711 | if (ret) | |
712 | return ret; | |
713 | /* Once validated, we can remove the merge point */ | |
714 | dbg_printf("Filter: remove one merge point at offset %lu\n", | |
715 | target_pc); | |
716 | ret = cds_lfht_del(merge_points, node); | |
717 | assert(!ret); | |
718 | } | |
719 | return 0; | |
720 | } | |
721 | ||
722 | /* | |
723 | * Return value: | |
724 | * >0: going to next insn. | |
725 | * 0: success, stop iteration. | |
726 | * <0: error | |
727 | */ | |
728 | static | |
729 | int exec_insn(struct bytecode_runtime *bytecode, | |
730 | struct cds_lfht *merge_points, | |
0305960f | 731 | struct vstack *stack, |
bf956ec0 MD |
732 | void **_next_pc, |
733 | void *pc) | |
734 | { | |
735 | int ret = 1; | |
736 | void *next_pc = *_next_pc; | |
737 | ||
738 | switch (*(filter_opcode_t *) pc) { | |
739 | case FILTER_OP_UNKNOWN: | |
740 | default: | |
741 | { | |
742 | ERR("unknown bytecode op %u\n", | |
743 | (unsigned int) *(filter_opcode_t *) pc); | |
744 | ret = -EINVAL; | |
745 | goto end; | |
746 | } | |
747 | ||
748 | case FILTER_OP_RETURN: | |
749 | { | |
750 | ret = 0; | |
751 | goto end; | |
752 | } | |
753 | ||
754 | /* binary */ | |
755 | case FILTER_OP_MUL: | |
756 | case FILTER_OP_DIV: | |
757 | case FILTER_OP_MOD: | |
758 | case FILTER_OP_PLUS: | |
759 | case FILTER_OP_MINUS: | |
760 | case FILTER_OP_RSHIFT: | |
761 | case FILTER_OP_LSHIFT: | |
762 | case FILTER_OP_BIN_AND: | |
763 | case FILTER_OP_BIN_OR: | |
764 | case FILTER_OP_BIN_XOR: | |
765 | { | |
766 | ERR("unsupported bytecode op %u\n", | |
767 | (unsigned int) *(filter_opcode_t *) pc); | |
768 | ret = -EINVAL; | |
769 | goto end; | |
770 | } | |
771 | ||
772 | case FILTER_OP_EQ: | |
773 | case FILTER_OP_NE: | |
774 | case FILTER_OP_GT: | |
775 | case FILTER_OP_LT: | |
776 | case FILTER_OP_GE: | |
777 | case FILTER_OP_LE: | |
778 | case FILTER_OP_EQ_STRING: | |
779 | case FILTER_OP_NE_STRING: | |
780 | case FILTER_OP_GT_STRING: | |
781 | case FILTER_OP_LT_STRING: | |
782 | case FILTER_OP_GE_STRING: | |
783 | case FILTER_OP_LE_STRING: | |
784 | case FILTER_OP_EQ_S64: | |
785 | case FILTER_OP_NE_S64: | |
786 | case FILTER_OP_GT_S64: | |
787 | case FILTER_OP_LT_S64: | |
788 | case FILTER_OP_GE_S64: | |
789 | case FILTER_OP_LE_S64: | |
bf956ec0 MD |
790 | case FILTER_OP_EQ_DOUBLE: |
791 | case FILTER_OP_NE_DOUBLE: | |
792 | case FILTER_OP_GT_DOUBLE: | |
793 | case FILTER_OP_LT_DOUBLE: | |
794 | case FILTER_OP_GE_DOUBLE: | |
795 | case FILTER_OP_LE_DOUBLE: | |
796 | { | |
0305960f MD |
797 | /* Pop 2, push 1 */ |
798 | if (vstack_pop(stack)) { | |
799 | ret = -EINVAL; | |
800 | goto end; | |
801 | } | |
802 | if (!vstack_ax(stack)) { | |
803 | ERR("Empty stack\n"); | |
804 | ret = -EINVAL; | |
805 | goto end; | |
806 | } | |
807 | vstack_ax(stack)->type = REG_S64; | |
bf956ec0 MD |
808 | next_pc += sizeof(struct binary_op); |
809 | break; | |
810 | } | |
811 | ||
812 | /* unary */ | |
813 | case FILTER_OP_UNARY_PLUS: | |
814 | case FILTER_OP_UNARY_MINUS: | |
815 | case FILTER_OP_UNARY_NOT: | |
816 | case FILTER_OP_UNARY_PLUS_S64: | |
817 | case FILTER_OP_UNARY_MINUS_S64: | |
818 | case FILTER_OP_UNARY_NOT_S64: | |
819 | { | |
0305960f MD |
820 | /* Pop 1, push 1 */ |
821 | if (!vstack_ax(stack)) { | |
822 | ERR("Empty stack\n"); | |
823 | ret = -EINVAL; | |
824 | goto end; | |
825 | } | |
826 | vstack_ax(stack)->type = REG_S64; | |
bf956ec0 MD |
827 | next_pc += sizeof(struct unary_op); |
828 | break; | |
829 | } | |
830 | ||
831 | case FILTER_OP_UNARY_PLUS_DOUBLE: | |
832 | case FILTER_OP_UNARY_MINUS_DOUBLE: | |
833 | case FILTER_OP_UNARY_NOT_DOUBLE: | |
834 | { | |
0305960f MD |
835 | /* Pop 1, push 1 */ |
836 | if (!vstack_ax(stack)) { | |
837 | ERR("Empty stack\n"); | |
838 | ret = -EINVAL; | |
839 | goto end; | |
840 | } | |
841 | vstack_ax(stack)->type = REG_DOUBLE; | |
bf956ec0 MD |
842 | next_pc += sizeof(struct unary_op); |
843 | break; | |
844 | } | |
845 | ||
846 | /* logical */ | |
847 | case FILTER_OP_AND: | |
848 | case FILTER_OP_OR: | |
849 | { | |
850 | struct logical_op *insn = (struct logical_op *) pc; | |
851 | int merge_ret; | |
852 | ||
853 | /* Add merge point to table */ | |
0305960f MD |
854 | merge_ret = merge_point_add(merge_points, insn->skip_offset, |
855 | stack); | |
bf956ec0 MD |
856 | if (merge_ret) { |
857 | ret = merge_ret; | |
858 | goto end; | |
97b58163 | 859 | } |
bf956ec0 MD |
860 | /* Continue to next instruction */ |
861 | next_pc += sizeof(struct logical_op); | |
862 | break; | |
863 | } | |
864 | ||
865 | /* load */ | |
866 | case FILTER_OP_LOAD_FIELD_REF: | |
867 | { | |
868 | ERR("Unknown field ref type\n"); | |
869 | ret = -EINVAL; | |
870 | goto end; | |
871 | } | |
872 | case FILTER_OP_LOAD_FIELD_REF_STRING: | |
873 | case FILTER_OP_LOAD_FIELD_REF_SEQUENCE: | |
874 | { | |
0305960f MD |
875 | if (vstack_push(stack)) { |
876 | ret = -EINVAL; | |
877 | goto end; | |
878 | } | |
879 | vstack_ax(stack)->type = REG_STRING; | |
bf956ec0 MD |
880 | next_pc += sizeof(struct load_op) + sizeof(struct field_ref); |
881 | break; | |
882 | } | |
883 | case FILTER_OP_LOAD_FIELD_REF_S64: | |
884 | { | |
0305960f MD |
885 | if (vstack_push(stack)) { |
886 | ret = -EINVAL; | |
887 | goto end; | |
888 | } | |
889 | vstack_ax(stack)->type = REG_S64; | |
bf956ec0 MD |
890 | next_pc += sizeof(struct load_op) + sizeof(struct field_ref); |
891 | break; | |
892 | } | |
893 | case FILTER_OP_LOAD_FIELD_REF_DOUBLE: | |
894 | { | |
0305960f MD |
895 | if (vstack_push(stack)) { |
896 | ret = -EINVAL; | |
897 | goto end; | |
898 | } | |
899 | vstack_ax(stack)->type = REG_DOUBLE; | |
bf956ec0 MD |
900 | next_pc += sizeof(struct load_op) + sizeof(struct field_ref); |
901 | break; | |
902 | } | |
903 | ||
904 | case FILTER_OP_LOAD_STRING: | |
905 | { | |
906 | struct load_op *insn = (struct load_op *) pc; | |
907 | ||
0305960f MD |
908 | if (vstack_push(stack)) { |
909 | ret = -EINVAL; | |
910 | goto end; | |
911 | } | |
912 | vstack_ax(stack)->type = REG_STRING; | |
bf956ec0 MD |
913 | next_pc += sizeof(struct load_op) + strlen(insn->data) + 1; |
914 | break; | |
915 | } | |
916 | ||
917 | case FILTER_OP_LOAD_S64: | |
918 | { | |
0305960f MD |
919 | if (vstack_push(stack)) { |
920 | ret = -EINVAL; | |
921 | goto end; | |
922 | } | |
923 | vstack_ax(stack)->type = REG_S64; | |
bf956ec0 MD |
924 | next_pc += sizeof(struct load_op) |
925 | + sizeof(struct literal_numeric); | |
926 | break; | |
927 | } | |
928 | ||
929 | case FILTER_OP_LOAD_DOUBLE: | |
930 | { | |
0305960f MD |
931 | if (vstack_push(stack)) { |
932 | ret = -EINVAL; | |
933 | goto end; | |
934 | } | |
935 | vstack_ax(stack)->type = REG_DOUBLE; | |
bf956ec0 MD |
936 | next_pc += sizeof(struct load_op) |
937 | + sizeof(struct literal_double); | |
938 | break; | |
939 | } | |
940 | ||
941 | case FILTER_OP_CAST_TO_S64: | |
942 | case FILTER_OP_CAST_DOUBLE_TO_S64: | |
943 | { | |
0305960f MD |
944 | /* Pop 1, push 1 */ |
945 | if (!vstack_ax(stack)) { | |
946 | ERR("Empty stack\n"); | |
947 | ret = -EINVAL; | |
948 | goto end; | |
949 | } | |
950 | vstack_ax(stack)->type = REG_S64; | |
bf956ec0 MD |
951 | next_pc += sizeof(struct cast_op); |
952 | break; | |
953 | } | |
954 | case FILTER_OP_CAST_NOP: | |
955 | { | |
956 | next_pc += sizeof(struct cast_op); | |
957 | break; | |
958 | } | |
97b58163 | 959 | |
bf956ec0 MD |
960 | } |
961 | end: | |
962 | *_next_pc = next_pc; | |
963 | return ret; | |
964 | } | |
965 | ||
966 | /* | |
967 | * Never called concurrently (hash seed is shared). | |
968 | */ | |
969 | int lttng_filter_validate_bytecode(struct bytecode_runtime *bytecode) | |
970 | { | |
971 | struct cds_lfht *merge_points; | |
972 | void *pc, *next_pc, *start_pc; | |
973 | int ret = -EINVAL; | |
0305960f | 974 | struct vstack stack; |
bf956ec0 | 975 | |
0305960f | 976 | vstack_init(&stack); |
bf956ec0 MD |
977 | |
978 | if (!lttng_hash_seed_ready) { | |
979 | lttng_hash_seed = time(NULL); | |
980 | lttng_hash_seed_ready = 1; | |
981 | } | |
982 | /* | |
983 | * Note: merge_points hash table used by single thread, and | |
984 | * never concurrently resized. Therefore, we can use it without | |
985 | * holding RCU read-side lock and free nodes without using | |
986 | * call_rcu. | |
987 | */ | |
988 | merge_points = cds_lfht_new(DEFAULT_NR_MERGE_POINTS, | |
989 | MIN_NR_BUCKETS, MAX_NR_BUCKETS, | |
990 | 0, NULL); | |
991 | if (!merge_points) { | |
992 | ERR("Error allocating hash table for bytecode validation\n"); | |
993 | return -ENOMEM; | |
994 | } | |
995 | start_pc = &bytecode->data[0]; | |
996 | for (pc = next_pc = start_pc; pc - start_pc < bytecode->len; | |
997 | pc = next_pc) { | |
998 | if (bytecode_validate_overflow(bytecode, start_pc, pc) != 0) { | |
999 | ERR("filter bytecode overflow\n"); | |
1000 | ret = -EINVAL; | |
1001 | goto end; | |
97b58163 | 1002 | } |
bf956ec0 MD |
1003 | dbg_printf("Validating op %s (%u)\n", |
1004 | print_op((unsigned int) *(filter_opcode_t *) pc), | |
1005 | (unsigned int) *(filter_opcode_t *) pc); | |
1006 | ||
1007 | /* | |
1008 | * For each instruction, validate the current context | |
1009 | * (traversal of entire execution flow), and validate | |
1010 | * all merge points targeting this instruction. | |
1011 | */ | |
1012 | ret = validate_instruction_all_contexts(bytecode, merge_points, | |
0305960f | 1013 | &stack, start_pc, pc); |
bf956ec0 MD |
1014 | if (ret) |
1015 | goto end; | |
0305960f | 1016 | ret = exec_insn(bytecode, merge_points, &stack, &next_pc, pc); |
bf956ec0 MD |
1017 | if (ret <= 0) |
1018 | goto end; | |
97b58163 MD |
1019 | } |
1020 | end: | |
bf956ec0 MD |
1021 | if (delete_all_nodes(merge_points)) { |
1022 | if (!ret) { | |
1023 | ERR("Unexpected merge points\n"); | |
1024 | ret = -EINVAL; | |
1025 | } | |
1026 | } | |
1027 | if (cds_lfht_destroy(merge_points, NULL)) { | |
1028 | ERR("Error destroying hash table\n"); | |
1029 | } | |
97b58163 MD |
1030 | return ret; |
1031 | } |