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 | |
02aca193 PP |
121 | int bin_op_compare_check(struct vstack *stack, const filter_opcode_t opcode, |
122 | const char *str) | |
07dfc1d0 MD |
123 | { |
124 | if (unlikely(!vstack_ax(stack) || !vstack_bx(stack))) | |
125 | goto error_unknown; | |
126 | ||
127 | switch (vstack_ax(stack)->type) { | |
128 | default: | |
129 | case REG_DOUBLE: | |
130 | goto error_unknown; | |
131 | ||
132 | case REG_STRING: | |
133 | switch (vstack_bx(stack)->type) { | |
134 | default: | |
135 | case REG_DOUBLE: | |
136 | goto error_unknown; | |
137 | ||
138 | case REG_STRING: | |
139 | break; | |
02aca193 PP |
140 | case REG_STAR_GLOB_STRING: |
141 | if (opcode != FILTER_OP_EQ && opcode != FILTER_OP_NE) { | |
142 | goto error_mismatch; | |
143 | } | |
144 | break; | |
145 | case REG_S64: | |
146 | goto error_mismatch; | |
147 | } | |
148 | break; | |
149 | case REG_STAR_GLOB_STRING: | |
150 | switch (vstack_bx(stack)->type) { | |
151 | default: | |
152 | case REG_DOUBLE: | |
153 | goto error_unknown; | |
154 | ||
155 | case REG_STRING: | |
156 | if (opcode != FILTER_OP_EQ && opcode != FILTER_OP_NE) { | |
157 | goto error_mismatch; | |
158 | } | |
159 | break; | |
160 | case REG_STAR_GLOB_STRING: | |
07dfc1d0 MD |
161 | case REG_S64: |
162 | goto error_mismatch; | |
163 | } | |
164 | break; | |
165 | case REG_S64: | |
166 | switch (vstack_bx(stack)->type) { | |
167 | default: | |
168 | case REG_DOUBLE: | |
169 | goto error_unknown; | |
170 | ||
171 | case REG_STRING: | |
02aca193 | 172 | case REG_STAR_GLOB_STRING: |
07dfc1d0 MD |
173 | goto error_mismatch; |
174 | ||
175 | case REG_S64: | |
176 | break; | |
177 | } | |
178 | break; | |
179 | } | |
180 | return 0; | |
181 | ||
182 | error_unknown: | |
183 | return -EINVAL; | |
184 | ||
185 | error_mismatch: | |
186 | printk(KERN_WARNING "type mismatch for '%s' binary operator\n", str); | |
187 | return -EINVAL; | |
188 | } | |
189 | ||
190 | /* | |
191 | * Validate bytecode range overflow within the validation pass. | |
192 | * Called for each instruction encountered. | |
193 | */ | |
194 | static | |
195 | int bytecode_validate_overflow(struct bytecode_runtime *bytecode, | |
7962cb86 | 196 | char *start_pc, char *pc) |
07dfc1d0 MD |
197 | { |
198 | int ret = 0; | |
199 | ||
200 | switch (*(filter_opcode_t *) pc) { | |
201 | case FILTER_OP_UNKNOWN: | |
202 | default: | |
203 | { | |
204 | printk(KERN_WARNING "unknown bytecode op %u\n", | |
205 | (unsigned int) *(filter_opcode_t *) pc); | |
206 | ret = -EINVAL; | |
207 | break; | |
208 | } | |
209 | ||
210 | case FILTER_OP_RETURN: | |
211 | { | |
212 | if (unlikely(pc + sizeof(struct return_op) | |
213 | > start_pc + bytecode->len)) { | |
214 | ret = -ERANGE; | |
215 | } | |
216 | break; | |
217 | } | |
218 | ||
219 | /* binary */ | |
220 | case FILTER_OP_MUL: | |
221 | case FILTER_OP_DIV: | |
222 | case FILTER_OP_MOD: | |
223 | case FILTER_OP_PLUS: | |
224 | case FILTER_OP_MINUS: | |
225 | case FILTER_OP_RSHIFT: | |
226 | case FILTER_OP_LSHIFT: | |
227 | case FILTER_OP_BIN_AND: | |
228 | case FILTER_OP_BIN_OR: | |
229 | case FILTER_OP_BIN_XOR: | |
230 | case FILTER_OP_EQ_DOUBLE: | |
231 | case FILTER_OP_NE_DOUBLE: | |
232 | case FILTER_OP_GT_DOUBLE: | |
233 | case FILTER_OP_LT_DOUBLE: | |
234 | case FILTER_OP_GE_DOUBLE: | |
235 | case FILTER_OP_LE_DOUBLE: | |
236 | /* Floating point */ | |
237 | case FILTER_OP_EQ_DOUBLE_S64: | |
238 | case FILTER_OP_NE_DOUBLE_S64: | |
239 | case FILTER_OP_GT_DOUBLE_S64: | |
240 | case FILTER_OP_LT_DOUBLE_S64: | |
241 | case FILTER_OP_GE_DOUBLE_S64: | |
242 | case FILTER_OP_LE_DOUBLE_S64: | |
243 | case FILTER_OP_EQ_S64_DOUBLE: | |
244 | case FILTER_OP_NE_S64_DOUBLE: | |
245 | case FILTER_OP_GT_S64_DOUBLE: | |
246 | case FILTER_OP_LT_S64_DOUBLE: | |
247 | case FILTER_OP_GE_S64_DOUBLE: | |
248 | case FILTER_OP_LE_S64_DOUBLE: | |
249 | case FILTER_OP_LOAD_FIELD_REF_DOUBLE: | |
250 | case FILTER_OP_GET_CONTEXT_REF_DOUBLE: | |
251 | case FILTER_OP_LOAD_DOUBLE: | |
252 | case FILTER_OP_CAST_DOUBLE_TO_S64: | |
253 | case FILTER_OP_UNARY_PLUS_DOUBLE: | |
254 | case FILTER_OP_UNARY_MINUS_DOUBLE: | |
255 | case FILTER_OP_UNARY_NOT_DOUBLE: | |
256 | { | |
257 | printk(KERN_WARNING "unsupported bytecode op %u\n", | |
258 | (unsigned int) *(filter_opcode_t *) pc); | |
259 | ret = -EINVAL; | |
260 | break; | |
261 | } | |
262 | ||
263 | case FILTER_OP_EQ: | |
264 | case FILTER_OP_NE: | |
265 | case FILTER_OP_GT: | |
266 | case FILTER_OP_LT: | |
267 | case FILTER_OP_GE: | |
268 | case FILTER_OP_LE: | |
269 | case FILTER_OP_EQ_STRING: | |
270 | case FILTER_OP_NE_STRING: | |
271 | case FILTER_OP_GT_STRING: | |
272 | case FILTER_OP_LT_STRING: | |
273 | case FILTER_OP_GE_STRING: | |
274 | case FILTER_OP_LE_STRING: | |
02aca193 PP |
275 | case FILTER_OP_EQ_STAR_GLOB_STRING: |
276 | case FILTER_OP_NE_STAR_GLOB_STRING: | |
07dfc1d0 MD |
277 | case FILTER_OP_EQ_S64: |
278 | case FILTER_OP_NE_S64: | |
279 | case FILTER_OP_GT_S64: | |
280 | case FILTER_OP_LT_S64: | |
281 | case FILTER_OP_GE_S64: | |
282 | case FILTER_OP_LE_S64: | |
283 | { | |
284 | if (unlikely(pc + sizeof(struct binary_op) | |
285 | > start_pc + bytecode->len)) { | |
286 | ret = -ERANGE; | |
287 | } | |
288 | break; | |
289 | } | |
290 | ||
291 | /* unary */ | |
292 | case FILTER_OP_UNARY_PLUS: | |
293 | case FILTER_OP_UNARY_MINUS: | |
294 | case FILTER_OP_UNARY_NOT: | |
295 | case FILTER_OP_UNARY_PLUS_S64: | |
296 | case FILTER_OP_UNARY_MINUS_S64: | |
297 | case FILTER_OP_UNARY_NOT_S64: | |
298 | { | |
299 | if (unlikely(pc + sizeof(struct unary_op) | |
300 | > start_pc + bytecode->len)) { | |
301 | ret = -ERANGE; | |
302 | } | |
303 | break; | |
304 | } | |
305 | ||
306 | /* logical */ | |
307 | case FILTER_OP_AND: | |
308 | case FILTER_OP_OR: | |
309 | { | |
310 | if (unlikely(pc + sizeof(struct logical_op) | |
311 | > start_pc + bytecode->len)) { | |
312 | ret = -ERANGE; | |
313 | } | |
314 | break; | |
315 | } | |
316 | ||
317 | /* load field ref */ | |
318 | case FILTER_OP_LOAD_FIELD_REF: | |
319 | { | |
320 | printk(KERN_WARNING "Unknown field ref type\n"); | |
321 | ret = -EINVAL; | |
322 | break; | |
323 | } | |
324 | /* get context ref */ | |
325 | case FILTER_OP_GET_CONTEXT_REF: | |
326 | { | |
327 | printk(KERN_WARNING "Unknown field ref type\n"); | |
328 | ret = -EINVAL; | |
329 | break; | |
330 | } | |
331 | case FILTER_OP_LOAD_FIELD_REF_STRING: | |
332 | case FILTER_OP_LOAD_FIELD_REF_SEQUENCE: | |
f127e61e MD |
333 | case FILTER_OP_LOAD_FIELD_REF_USER_STRING: |
334 | case FILTER_OP_LOAD_FIELD_REF_USER_SEQUENCE: | |
07dfc1d0 MD |
335 | case FILTER_OP_LOAD_FIELD_REF_S64: |
336 | case FILTER_OP_GET_CONTEXT_REF_STRING: | |
337 | case FILTER_OP_GET_CONTEXT_REF_S64: | |
338 | { | |
339 | if (unlikely(pc + sizeof(struct load_op) + sizeof(struct field_ref) | |
340 | > start_pc + bytecode->len)) { | |
341 | ret = -ERANGE; | |
342 | } | |
343 | break; | |
344 | } | |
345 | ||
346 | /* load from immediate operand */ | |
347 | case FILTER_OP_LOAD_STRING: | |
02aca193 | 348 | case FILTER_OP_LOAD_STAR_GLOB_STRING: |
07dfc1d0 MD |
349 | { |
350 | struct load_op *insn = (struct load_op *) pc; | |
351 | uint32_t str_len, maxlen; | |
352 | ||
353 | if (unlikely(pc + sizeof(struct load_op) | |
354 | > start_pc + bytecode->len)) { | |
355 | ret = -ERANGE; | |
356 | break; | |
357 | } | |
358 | ||
359 | maxlen = start_pc + bytecode->len - pc - sizeof(struct load_op); | |
360 | str_len = strnlen(insn->data, maxlen); | |
361 | if (unlikely(str_len >= maxlen)) { | |
362 | /* Final '\0' not found within range */ | |
363 | ret = -ERANGE; | |
364 | } | |
365 | break; | |
366 | } | |
367 | ||
368 | case FILTER_OP_LOAD_S64: | |
369 | { | |
370 | if (unlikely(pc + sizeof(struct load_op) + sizeof(struct literal_numeric) | |
371 | > start_pc + bytecode->len)) { | |
372 | ret = -ERANGE; | |
373 | } | |
374 | break; | |
375 | } | |
376 | ||
377 | case FILTER_OP_CAST_TO_S64: | |
378 | case FILTER_OP_CAST_NOP: | |
379 | { | |
380 | if (unlikely(pc + sizeof(struct cast_op) | |
381 | > start_pc + bytecode->len)) { | |
382 | ret = -ERANGE; | |
383 | } | |
384 | break; | |
385 | } | |
386 | ||
387 | } | |
388 | ||
389 | return ret; | |
390 | } | |
391 | ||
392 | static | |
393 | unsigned long delete_all_nodes(struct mp_table *mp_table) | |
394 | { | |
395 | struct mp_node *mp_node; | |
396 | struct hlist_node *tmp; | |
397 | unsigned long nr_nodes = 0; | |
398 | int i; | |
399 | ||
400 | for (i = 0; i < MERGE_POINT_TABLE_SIZE; i++) { | |
401 | struct hlist_head *head; | |
402 | ||
403 | head = &mp_table->mp_head[i]; | |
d216ecae | 404 | lttng_hlist_for_each_entry_safe(mp_node, tmp, head, node) { |
07dfc1d0 MD |
405 | kfree(mp_node); |
406 | nr_nodes++; | |
407 | } | |
408 | } | |
409 | return nr_nodes; | |
410 | } | |
411 | ||
412 | /* | |
413 | * Return value: | |
414 | * 0: success | |
415 | * <0: error | |
416 | */ | |
417 | static | |
418 | int validate_instruction_context(struct bytecode_runtime *bytecode, | |
419 | struct vstack *stack, | |
7962cb86 MD |
420 | char *start_pc, |
421 | char *pc) | |
07dfc1d0 MD |
422 | { |
423 | int ret = 0; | |
02aca193 | 424 | const filter_opcode_t opcode = *(filter_opcode_t *) pc; |
07dfc1d0 | 425 | |
02aca193 | 426 | switch (opcode) { |
07dfc1d0 MD |
427 | case FILTER_OP_UNKNOWN: |
428 | default: | |
429 | { | |
430 | printk(KERN_WARNING "unknown bytecode op %u\n", | |
431 | (unsigned int) *(filter_opcode_t *) pc); | |
432 | ret = -EINVAL; | |
433 | goto end; | |
434 | } | |
435 | ||
436 | case FILTER_OP_RETURN: | |
437 | { | |
438 | goto end; | |
439 | } | |
440 | ||
441 | /* binary */ | |
442 | case FILTER_OP_MUL: | |
443 | case FILTER_OP_DIV: | |
444 | case FILTER_OP_MOD: | |
445 | case FILTER_OP_PLUS: | |
446 | case FILTER_OP_MINUS: | |
447 | case FILTER_OP_RSHIFT: | |
448 | case FILTER_OP_LSHIFT: | |
449 | case FILTER_OP_BIN_AND: | |
450 | case FILTER_OP_BIN_OR: | |
451 | case FILTER_OP_BIN_XOR: | |
452 | /* Floating point */ | |
453 | case FILTER_OP_EQ_DOUBLE: | |
454 | case FILTER_OP_NE_DOUBLE: | |
455 | case FILTER_OP_GT_DOUBLE: | |
456 | case FILTER_OP_LT_DOUBLE: | |
457 | case FILTER_OP_GE_DOUBLE: | |
458 | case FILTER_OP_LE_DOUBLE: | |
459 | case FILTER_OP_EQ_DOUBLE_S64: | |
460 | case FILTER_OP_NE_DOUBLE_S64: | |
461 | case FILTER_OP_GT_DOUBLE_S64: | |
462 | case FILTER_OP_LT_DOUBLE_S64: | |
463 | case FILTER_OP_GE_DOUBLE_S64: | |
464 | case FILTER_OP_LE_DOUBLE_S64: | |
465 | case FILTER_OP_EQ_S64_DOUBLE: | |
466 | case FILTER_OP_NE_S64_DOUBLE: | |
467 | case FILTER_OP_GT_S64_DOUBLE: | |
468 | case FILTER_OP_LT_S64_DOUBLE: | |
469 | case FILTER_OP_GE_S64_DOUBLE: | |
470 | case FILTER_OP_LE_S64_DOUBLE: | |
471 | case FILTER_OP_UNARY_PLUS_DOUBLE: | |
472 | case FILTER_OP_UNARY_MINUS_DOUBLE: | |
473 | case FILTER_OP_UNARY_NOT_DOUBLE: | |
474 | case FILTER_OP_LOAD_FIELD_REF_DOUBLE: | |
475 | case FILTER_OP_LOAD_DOUBLE: | |
476 | case FILTER_OP_CAST_DOUBLE_TO_S64: | |
477 | case FILTER_OP_GET_CONTEXT_REF_DOUBLE: | |
478 | { | |
479 | printk(KERN_WARNING "unsupported bytecode op %u\n", | |
480 | (unsigned int) *(filter_opcode_t *) pc); | |
481 | ret = -EINVAL; | |
482 | goto end; | |
483 | } | |
484 | ||
485 | case FILTER_OP_EQ: | |
486 | { | |
02aca193 | 487 | ret = bin_op_compare_check(stack, opcode, "=="); |
07dfc1d0 MD |
488 | if (ret) |
489 | goto end; | |
490 | break; | |
491 | } | |
492 | case FILTER_OP_NE: | |
493 | { | |
02aca193 | 494 | ret = bin_op_compare_check(stack, opcode, "!="); |
07dfc1d0 MD |
495 | if (ret) |
496 | goto end; | |
497 | break; | |
498 | } | |
499 | case FILTER_OP_GT: | |
500 | { | |
02aca193 | 501 | ret = bin_op_compare_check(stack, opcode, ">"); |
07dfc1d0 MD |
502 | if (ret) |
503 | goto end; | |
504 | break; | |
505 | } | |
506 | case FILTER_OP_LT: | |
507 | { | |
02aca193 | 508 | ret = bin_op_compare_check(stack, opcode, "<"); |
07dfc1d0 MD |
509 | if (ret) |
510 | goto end; | |
511 | break; | |
512 | } | |
513 | case FILTER_OP_GE: | |
514 | { | |
02aca193 | 515 | ret = bin_op_compare_check(stack, opcode, ">="); |
07dfc1d0 MD |
516 | if (ret) |
517 | goto end; | |
518 | break; | |
519 | } | |
520 | case FILTER_OP_LE: | |
521 | { | |
02aca193 | 522 | ret = bin_op_compare_check(stack, opcode, "<="); |
07dfc1d0 MD |
523 | if (ret) |
524 | goto end; | |
525 | break; | |
526 | } | |
527 | ||
528 | case FILTER_OP_EQ_STRING: | |
529 | case FILTER_OP_NE_STRING: | |
530 | case FILTER_OP_GT_STRING: | |
531 | case FILTER_OP_LT_STRING: | |
532 | case FILTER_OP_GE_STRING: | |
533 | case FILTER_OP_LE_STRING: | |
534 | { | |
535 | if (!vstack_ax(stack) || !vstack_bx(stack)) { | |
536 | printk(KERN_WARNING "Empty stack\n"); | |
537 | ret = -EINVAL; | |
538 | goto end; | |
539 | } | |
540 | if (vstack_ax(stack)->type != REG_STRING | |
541 | || vstack_bx(stack)->type != REG_STRING) { | |
542 | printk(KERN_WARNING "Unexpected register type for string comparator\n"); | |
543 | ret = -EINVAL; | |
544 | goto end; | |
545 | } | |
546 | break; | |
547 | } | |
548 | ||
02aca193 PP |
549 | |
550 | case FILTER_OP_EQ_STAR_GLOB_STRING: | |
551 | case FILTER_OP_NE_STAR_GLOB_STRING: | |
552 | { | |
553 | if (!vstack_ax(stack) || !vstack_bx(stack)) { | |
554 | printk(KERN_WARNING "Empty stack\n"); | |
555 | ret = -EINVAL; | |
556 | goto end; | |
557 | } | |
558 | if (vstack_ax(stack)->type != REG_STAR_GLOB_STRING | |
559 | && vstack_bx(stack)->type != REG_STAR_GLOB_STRING) { | |
560 | printk(KERN_WARNING "Unexpected register type for globbing pattern comparator\n"); | |
561 | ret = -EINVAL; | |
562 | goto end; | |
563 | } | |
564 | break; | |
565 | } | |
566 | ||
07dfc1d0 MD |
567 | case FILTER_OP_EQ_S64: |
568 | case FILTER_OP_NE_S64: | |
569 | case FILTER_OP_GT_S64: | |
570 | case FILTER_OP_LT_S64: | |
571 | case FILTER_OP_GE_S64: | |
572 | case FILTER_OP_LE_S64: | |
573 | { | |
574 | if (!vstack_ax(stack) || !vstack_bx(stack)) { | |
575 | printk(KERN_WARNING "Empty stack\n"); | |
576 | ret = -EINVAL; | |
577 | goto end; | |
578 | } | |
579 | if (vstack_ax(stack)->type != REG_S64 | |
580 | || vstack_bx(stack)->type != REG_S64) { | |
581 | printk(KERN_WARNING "Unexpected register type for s64 comparator\n"); | |
582 | ret = -EINVAL; | |
583 | goto end; | |
584 | } | |
585 | break; | |
586 | } | |
587 | ||
588 | /* unary */ | |
589 | case FILTER_OP_UNARY_PLUS: | |
590 | case FILTER_OP_UNARY_MINUS: | |
591 | case FILTER_OP_UNARY_NOT: | |
592 | { | |
593 | if (!vstack_ax(stack)) { | |
594 | printk(KERN_WARNING "Empty stack\n"); | |
595 | ret = -EINVAL; | |
596 | goto end; | |
597 | } | |
598 | switch (vstack_ax(stack)->type) { | |
599 | default: | |
600 | case REG_DOUBLE: | |
601 | printk(KERN_WARNING "unknown register type\n"); | |
602 | ret = -EINVAL; | |
603 | goto end; | |
604 | ||
605 | case REG_STRING: | |
02aca193 | 606 | case REG_STAR_GLOB_STRING: |
07dfc1d0 MD |
607 | printk(KERN_WARNING "Unary op can only be applied to numeric or floating point registers\n"); |
608 | ret = -EINVAL; | |
609 | goto end; | |
610 | case REG_S64: | |
611 | break; | |
612 | } | |
613 | break; | |
614 | } | |
615 | ||
616 | case FILTER_OP_UNARY_PLUS_S64: | |
617 | case FILTER_OP_UNARY_MINUS_S64: | |
618 | case FILTER_OP_UNARY_NOT_S64: | |
619 | { | |
620 | if (!vstack_ax(stack)) { | |
621 | printk(KERN_WARNING "Empty stack\n"); | |
622 | ret = -EINVAL; | |
623 | goto end; | |
624 | } | |
625 | if (vstack_ax(stack)->type != REG_S64) { | |
626 | printk(KERN_WARNING "Invalid register type\n"); | |
627 | ret = -EINVAL; | |
628 | goto end; | |
629 | } | |
630 | break; | |
631 | } | |
632 | ||
633 | /* logical */ | |
634 | case FILTER_OP_AND: | |
635 | case FILTER_OP_OR: | |
636 | { | |
637 | struct logical_op *insn = (struct logical_op *) pc; | |
638 | ||
639 | if (!vstack_ax(stack)) { | |
640 | printk(KERN_WARNING "Empty stack\n"); | |
641 | ret = -EINVAL; | |
642 | goto end; | |
643 | } | |
644 | if (vstack_ax(stack)->type != REG_S64) { | |
645 | printk(KERN_WARNING "Logical comparator expects S64 register\n"); | |
646 | ret = -EINVAL; | |
647 | goto end; | |
648 | } | |
649 | ||
650 | dbg_printk("Validate jumping to bytecode offset %u\n", | |
651 | (unsigned int) insn->skip_offset); | |
652 | if (unlikely(start_pc + insn->skip_offset <= pc)) { | |
653 | printk(KERN_WARNING "Loops are not allowed in bytecode\n"); | |
654 | ret = -EINVAL; | |
655 | goto end; | |
656 | } | |
657 | break; | |
658 | } | |
659 | ||
660 | /* load field ref */ | |
661 | case FILTER_OP_LOAD_FIELD_REF: | |
662 | { | |
663 | printk(KERN_WARNING "Unknown field ref type\n"); | |
664 | ret = -EINVAL; | |
665 | goto end; | |
666 | } | |
667 | case FILTER_OP_LOAD_FIELD_REF_STRING: | |
668 | case FILTER_OP_LOAD_FIELD_REF_SEQUENCE: | |
f127e61e MD |
669 | case FILTER_OP_LOAD_FIELD_REF_USER_STRING: |
670 | case FILTER_OP_LOAD_FIELD_REF_USER_SEQUENCE: | |
07dfc1d0 MD |
671 | { |
672 | struct load_op *insn = (struct load_op *) pc; | |
673 | struct field_ref *ref = (struct field_ref *) insn->data; | |
674 | ||
675 | dbg_printk("Validate load field ref offset %u type string\n", | |
676 | ref->offset); | |
677 | break; | |
678 | } | |
679 | case FILTER_OP_LOAD_FIELD_REF_S64: | |
680 | { | |
681 | struct load_op *insn = (struct load_op *) pc; | |
682 | struct field_ref *ref = (struct field_ref *) insn->data; | |
683 | ||
684 | dbg_printk("Validate load field ref offset %u type s64\n", | |
685 | ref->offset); | |
686 | break; | |
687 | } | |
688 | ||
689 | /* load from immediate operand */ | |
690 | case FILTER_OP_LOAD_STRING: | |
02aca193 | 691 | case FILTER_OP_LOAD_STAR_GLOB_STRING: |
07dfc1d0 MD |
692 | { |
693 | break; | |
694 | } | |
695 | ||
696 | case FILTER_OP_LOAD_S64: | |
697 | { | |
698 | break; | |
699 | } | |
700 | ||
701 | case FILTER_OP_CAST_TO_S64: | |
702 | { | |
703 | struct cast_op *insn = (struct cast_op *) pc; | |
704 | ||
705 | if (!vstack_ax(stack)) { | |
706 | printk(KERN_WARNING "Empty stack\n"); | |
707 | ret = -EINVAL; | |
708 | goto end; | |
709 | } | |
710 | switch (vstack_ax(stack)->type) { | |
711 | default: | |
712 | case REG_DOUBLE: | |
713 | printk(KERN_WARNING "unknown register type\n"); | |
714 | ret = -EINVAL; | |
715 | goto end; | |
716 | ||
717 | case REG_STRING: | |
02aca193 | 718 | case REG_STAR_GLOB_STRING: |
07dfc1d0 MD |
719 | printk(KERN_WARNING "Cast op can only be applied to numeric or floating point registers\n"); |
720 | ret = -EINVAL; | |
721 | goto end; | |
722 | case REG_S64: | |
723 | break; | |
724 | } | |
725 | if (insn->op == FILTER_OP_CAST_DOUBLE_TO_S64) { | |
726 | if (vstack_ax(stack)->type != REG_DOUBLE) { | |
727 | printk(KERN_WARNING "Cast expects double\n"); | |
728 | ret = -EINVAL; | |
729 | goto end; | |
730 | } | |
731 | } | |
732 | break; | |
733 | } | |
734 | case FILTER_OP_CAST_NOP: | |
735 | { | |
736 | break; | |
737 | } | |
738 | ||
739 | /* get context ref */ | |
740 | case FILTER_OP_GET_CONTEXT_REF: | |
741 | { | |
742 | printk(KERN_WARNING "Unknown get context ref type\n"); | |
743 | ret = -EINVAL; | |
744 | goto end; | |
745 | } | |
746 | case FILTER_OP_GET_CONTEXT_REF_STRING: | |
747 | { | |
748 | struct load_op *insn = (struct load_op *) pc; | |
749 | struct field_ref *ref = (struct field_ref *) insn->data; | |
750 | ||
751 | dbg_printk("Validate get context ref offset %u type string\n", | |
752 | ref->offset); | |
753 | break; | |
754 | } | |
755 | case FILTER_OP_GET_CONTEXT_REF_S64: | |
756 | { | |
757 | struct load_op *insn = (struct load_op *) pc; | |
758 | struct field_ref *ref = (struct field_ref *) insn->data; | |
759 | ||
760 | dbg_printk("Validate get context ref offset %u type s64\n", | |
761 | ref->offset); | |
762 | break; | |
763 | } | |
764 | ||
765 | } | |
766 | end: | |
767 | return ret; | |
768 | } | |
769 | ||
770 | /* | |
771 | * Return value: | |
772 | * 0: success | |
773 | * <0: error | |
774 | */ | |
775 | static | |
776 | int validate_instruction_all_contexts(struct bytecode_runtime *bytecode, | |
777 | struct mp_table *mp_table, | |
778 | struct vstack *stack, | |
7962cb86 MD |
779 | char *start_pc, |
780 | char *pc) | |
07dfc1d0 MD |
781 | { |
782 | int ret, found = 0; | |
783 | unsigned long target_pc = pc - start_pc; | |
784 | unsigned long hash; | |
785 | struct hlist_head *head; | |
786 | struct mp_node *mp_node; | |
787 | ||
788 | /* Validate the context resulting from the previous instruction */ | |
789 | ret = validate_instruction_context(bytecode, stack, start_pc, pc); | |
790 | if (ret) | |
791 | return ret; | |
792 | ||
793 | /* Validate merge points */ | |
794 | hash = jhash_1word(target_pc, 0); | |
795 | head = &mp_table->mp_head[hash & (MERGE_POINT_TABLE_SIZE - 1)]; | |
d216ecae | 796 | lttng_hlist_for_each_entry(mp_node, head, node) { |
07dfc1d0 MD |
797 | if (lttng_hash_match(mp_node, target_pc)) { |
798 | found = 1; | |
799 | break; | |
800 | } | |
801 | } | |
802 | if (found) { | |
803 | dbg_printk("Filter: validate merge point at offset %lu\n", | |
804 | target_pc); | |
805 | if (merge_points_compare(stack, &mp_node->stack)) { | |
806 | printk(KERN_WARNING "Merge points differ for offset %lu\n", | |
807 | target_pc); | |
808 | return -EINVAL; | |
809 | } | |
810 | /* Once validated, we can remove the merge point */ | |
811 | dbg_printk("Filter: remove merge point at offset %lu\n", | |
812 | target_pc); | |
813 | hlist_del(&mp_node->node); | |
814 | } | |
815 | return 0; | |
816 | } | |
817 | ||
818 | /* | |
819 | * Return value: | |
820 | * >0: going to next insn. | |
821 | * 0: success, stop iteration. | |
822 | * <0: error | |
823 | */ | |
824 | static | |
825 | int exec_insn(struct bytecode_runtime *bytecode, | |
826 | struct mp_table *mp_table, | |
827 | struct vstack *stack, | |
7962cb86 MD |
828 | char **_next_pc, |
829 | char *pc) | |
07dfc1d0 MD |
830 | { |
831 | int ret = 1; | |
7962cb86 | 832 | char *next_pc = *_next_pc; |
07dfc1d0 MD |
833 | |
834 | switch (*(filter_opcode_t *) pc) { | |
835 | case FILTER_OP_UNKNOWN: | |
836 | default: | |
837 | { | |
838 | printk(KERN_WARNING "unknown bytecode op %u\n", | |
839 | (unsigned int) *(filter_opcode_t *) pc); | |
840 | ret = -EINVAL; | |
841 | goto end; | |
842 | } | |
843 | ||
844 | case FILTER_OP_RETURN: | |
845 | { | |
846 | if (!vstack_ax(stack)) { | |
847 | printk(KERN_WARNING "Empty stack\n"); | |
848 | ret = -EINVAL; | |
849 | goto end; | |
850 | } | |
851 | ret = 0; | |
852 | goto end; | |
853 | } | |
854 | ||
855 | /* binary */ | |
856 | case FILTER_OP_MUL: | |
857 | case FILTER_OP_DIV: | |
858 | case FILTER_OP_MOD: | |
859 | case FILTER_OP_PLUS: | |
860 | case FILTER_OP_MINUS: | |
861 | case FILTER_OP_RSHIFT: | |
862 | case FILTER_OP_LSHIFT: | |
863 | case FILTER_OP_BIN_AND: | |
864 | case FILTER_OP_BIN_OR: | |
865 | case FILTER_OP_BIN_XOR: | |
866 | /* Floating point */ | |
867 | case FILTER_OP_EQ_DOUBLE: | |
868 | case FILTER_OP_NE_DOUBLE: | |
869 | case FILTER_OP_GT_DOUBLE: | |
870 | case FILTER_OP_LT_DOUBLE: | |
871 | case FILTER_OP_GE_DOUBLE: | |
872 | case FILTER_OP_LE_DOUBLE: | |
873 | case FILTER_OP_EQ_DOUBLE_S64: | |
874 | case FILTER_OP_NE_DOUBLE_S64: | |
875 | case FILTER_OP_GT_DOUBLE_S64: | |
876 | case FILTER_OP_LT_DOUBLE_S64: | |
877 | case FILTER_OP_GE_DOUBLE_S64: | |
878 | case FILTER_OP_LE_DOUBLE_S64: | |
879 | case FILTER_OP_EQ_S64_DOUBLE: | |
880 | case FILTER_OP_NE_S64_DOUBLE: | |
881 | case FILTER_OP_GT_S64_DOUBLE: | |
882 | case FILTER_OP_LT_S64_DOUBLE: | |
883 | case FILTER_OP_GE_S64_DOUBLE: | |
884 | case FILTER_OP_LE_S64_DOUBLE: | |
885 | case FILTER_OP_UNARY_PLUS_DOUBLE: | |
886 | case FILTER_OP_UNARY_MINUS_DOUBLE: | |
887 | case FILTER_OP_UNARY_NOT_DOUBLE: | |
888 | case FILTER_OP_LOAD_FIELD_REF_DOUBLE: | |
889 | case FILTER_OP_GET_CONTEXT_REF_DOUBLE: | |
890 | case FILTER_OP_LOAD_DOUBLE: | |
891 | case FILTER_OP_CAST_DOUBLE_TO_S64: | |
892 | { | |
893 | printk(KERN_WARNING "unsupported bytecode op %u\n", | |
894 | (unsigned int) *(filter_opcode_t *) pc); | |
895 | ret = -EINVAL; | |
896 | goto end; | |
897 | } | |
898 | ||
899 | case FILTER_OP_EQ: | |
900 | case FILTER_OP_NE: | |
901 | case FILTER_OP_GT: | |
902 | case FILTER_OP_LT: | |
903 | case FILTER_OP_GE: | |
904 | case FILTER_OP_LE: | |
905 | case FILTER_OP_EQ_STRING: | |
906 | case FILTER_OP_NE_STRING: | |
907 | case FILTER_OP_GT_STRING: | |
908 | case FILTER_OP_LT_STRING: | |
909 | case FILTER_OP_GE_STRING: | |
910 | case FILTER_OP_LE_STRING: | |
02aca193 PP |
911 | case FILTER_OP_EQ_STAR_GLOB_STRING: |
912 | case FILTER_OP_NE_STAR_GLOB_STRING: | |
07dfc1d0 MD |
913 | case FILTER_OP_EQ_S64: |
914 | case FILTER_OP_NE_S64: | |
915 | case FILTER_OP_GT_S64: | |
916 | case FILTER_OP_LT_S64: | |
917 | case FILTER_OP_GE_S64: | |
918 | case FILTER_OP_LE_S64: | |
919 | { | |
920 | /* Pop 2, push 1 */ | |
921 | if (vstack_pop(stack)) { | |
922 | ret = -EINVAL; | |
923 | goto end; | |
924 | } | |
925 | if (!vstack_ax(stack)) { | |
926 | printk(KERN_WARNING "Empty stack\n"); | |
927 | ret = -EINVAL; | |
928 | goto end; | |
929 | } | |
930 | vstack_ax(stack)->type = REG_S64; | |
931 | next_pc += sizeof(struct binary_op); | |
932 | break; | |
933 | } | |
934 | ||
935 | /* unary */ | |
936 | case FILTER_OP_UNARY_PLUS: | |
937 | case FILTER_OP_UNARY_MINUS: | |
938 | case FILTER_OP_UNARY_NOT: | |
939 | case FILTER_OP_UNARY_PLUS_S64: | |
940 | case FILTER_OP_UNARY_MINUS_S64: | |
941 | case FILTER_OP_UNARY_NOT_S64: | |
942 | { | |
943 | /* Pop 1, push 1 */ | |
944 | if (!vstack_ax(stack)) { | |
945 | printk(KERN_WARNING "Empty stack\n"); | |
946 | ret = -EINVAL; | |
947 | goto end; | |
948 | } | |
949 | vstack_ax(stack)->type = REG_S64; | |
950 | next_pc += sizeof(struct unary_op); | |
951 | break; | |
952 | } | |
953 | ||
954 | /* logical */ | |
955 | case FILTER_OP_AND: | |
956 | case FILTER_OP_OR: | |
957 | { | |
958 | struct logical_op *insn = (struct logical_op *) pc; | |
959 | int merge_ret; | |
960 | ||
961 | /* Add merge point to table */ | |
962 | merge_ret = merge_point_add_check(mp_table, | |
963 | insn->skip_offset, stack); | |
964 | if (merge_ret) { | |
965 | ret = merge_ret; | |
966 | goto end; | |
967 | } | |
968 | /* Continue to next instruction */ | |
969 | /* Pop 1 when jump not taken */ | |
970 | if (vstack_pop(stack)) { | |
971 | ret = -EINVAL; | |
972 | goto end; | |
973 | } | |
974 | next_pc += sizeof(struct logical_op); | |
975 | break; | |
976 | } | |
977 | ||
978 | /* load field ref */ | |
979 | case FILTER_OP_LOAD_FIELD_REF: | |
980 | { | |
981 | printk(KERN_WARNING "Unknown field ref type\n"); | |
982 | ret = -EINVAL; | |
983 | goto end; | |
984 | } | |
985 | /* get context ref */ | |
986 | case FILTER_OP_GET_CONTEXT_REF: | |
987 | { | |
988 | printk(KERN_WARNING "Unknown get context ref type\n"); | |
989 | ret = -EINVAL; | |
990 | goto end; | |
991 | } | |
992 | case FILTER_OP_LOAD_FIELD_REF_STRING: | |
993 | case FILTER_OP_LOAD_FIELD_REF_SEQUENCE: | |
994 | case FILTER_OP_GET_CONTEXT_REF_STRING: | |
f127e61e MD |
995 | case FILTER_OP_LOAD_FIELD_REF_USER_STRING: |
996 | case FILTER_OP_LOAD_FIELD_REF_USER_SEQUENCE: | |
07dfc1d0 MD |
997 | { |
998 | if (vstack_push(stack)) { | |
999 | ret = -EINVAL; | |
1000 | goto end; | |
1001 | } | |
1002 | vstack_ax(stack)->type = REG_STRING; | |
1003 | next_pc += sizeof(struct load_op) + sizeof(struct field_ref); | |
1004 | break; | |
1005 | } | |
1006 | case FILTER_OP_LOAD_FIELD_REF_S64: | |
1007 | case FILTER_OP_GET_CONTEXT_REF_S64: | |
1008 | { | |
1009 | if (vstack_push(stack)) { | |
1010 | ret = -EINVAL; | |
1011 | goto end; | |
1012 | } | |
1013 | vstack_ax(stack)->type = REG_S64; | |
1014 | next_pc += sizeof(struct load_op) + sizeof(struct field_ref); | |
1015 | break; | |
1016 | } | |
1017 | ||
1018 | /* load from immediate operand */ | |
1019 | case FILTER_OP_LOAD_STRING: | |
1020 | { | |
1021 | struct load_op *insn = (struct load_op *) pc; | |
1022 | ||
1023 | if (vstack_push(stack)) { | |
1024 | ret = -EINVAL; | |
1025 | goto end; | |
1026 | } | |
1027 | vstack_ax(stack)->type = REG_STRING; | |
1028 | next_pc += sizeof(struct load_op) + strlen(insn->data) + 1; | |
02aca193 PP |
1029 | break; |
1030 | } | |
1031 | ||
1032 | case FILTER_OP_LOAD_STAR_GLOB_STRING: | |
1033 | { | |
1034 | struct load_op *insn = (struct load_op *) pc; | |
1035 | ||
1036 | if (vstack_push(stack)) { | |
1037 | ret = -EINVAL; | |
1038 | goto end; | |
1039 | } | |
1040 | vstack_ax(stack)->type = REG_STAR_GLOB_STRING; | |
1041 | next_pc += sizeof(struct load_op) + strlen(insn->data) + 1; | |
07dfc1d0 MD |
1042 | break; |
1043 | } | |
1044 | ||
1045 | case FILTER_OP_LOAD_S64: | |
1046 | { | |
1047 | if (vstack_push(stack)) { | |
1048 | ret = -EINVAL; | |
1049 | goto end; | |
1050 | } | |
1051 | vstack_ax(stack)->type = REG_S64; | |
1052 | next_pc += sizeof(struct load_op) | |
1053 | + sizeof(struct literal_numeric); | |
1054 | break; | |
1055 | } | |
1056 | ||
1057 | case FILTER_OP_CAST_TO_S64: | |
1058 | { | |
1059 | /* Pop 1, push 1 */ | |
1060 | if (!vstack_ax(stack)) { | |
1061 | printk(KERN_WARNING "Empty stack\n"); | |
1062 | ret = -EINVAL; | |
1063 | goto end; | |
1064 | } | |
1065 | vstack_ax(stack)->type = REG_S64; | |
1066 | next_pc += sizeof(struct cast_op); | |
1067 | break; | |
1068 | } | |
1069 | case FILTER_OP_CAST_NOP: | |
1070 | { | |
1071 | next_pc += sizeof(struct cast_op); | |
1072 | break; | |
1073 | } | |
1074 | ||
1075 | } | |
1076 | end: | |
1077 | *_next_pc = next_pc; | |
1078 | return ret; | |
1079 | } | |
1080 | ||
1081 | /* | |
1082 | * Never called concurrently (hash seed is shared). | |
1083 | */ | |
1084 | int lttng_filter_validate_bytecode(struct bytecode_runtime *bytecode) | |
1085 | { | |
1086 | struct mp_table *mp_table; | |
7962cb86 | 1087 | char *pc, *next_pc, *start_pc; |
07dfc1d0 MD |
1088 | int ret = -EINVAL; |
1089 | struct vstack stack; | |
1090 | ||
1091 | vstack_init(&stack); | |
1092 | ||
1093 | mp_table = kzalloc(sizeof(*mp_table), GFP_KERNEL); | |
1094 | if (!mp_table) { | |
1095 | printk(KERN_WARNING "Error allocating hash table for bytecode validation\n"); | |
1096 | return -ENOMEM; | |
1097 | } | |
1098 | start_pc = &bytecode->data[0]; | |
1099 | for (pc = next_pc = start_pc; pc - start_pc < bytecode->len; | |
1100 | pc = next_pc) { | |
1101 | ret = bytecode_validate_overflow(bytecode, start_pc, pc); | |
1102 | if (ret != 0) { | |
1103 | if (ret == -ERANGE) | |
1104 | printk(KERN_WARNING "filter bytecode overflow\n"); | |
1105 | goto end; | |
1106 | } | |
1107 | dbg_printk("Validating op %s (%u)\n", | |
1108 | lttng_filter_print_op((unsigned int) *(filter_opcode_t *) pc), | |
1109 | (unsigned int) *(filter_opcode_t *) pc); | |
1110 | ||
1111 | /* | |
1112 | * For each instruction, validate the current context | |
1113 | * (traversal of entire execution flow), and validate | |
1114 | * all merge points targeting this instruction. | |
1115 | */ | |
1116 | ret = validate_instruction_all_contexts(bytecode, mp_table, | |
1117 | &stack, start_pc, pc); | |
1118 | if (ret) | |
1119 | goto end; | |
1120 | ret = exec_insn(bytecode, mp_table, &stack, &next_pc, pc); | |
1121 | if (ret <= 0) | |
1122 | goto end; | |
1123 | } | |
1124 | end: | |
1125 | if (delete_all_nodes(mp_table)) { | |
1126 | if (!ret) { | |
1127 | printk(KERN_WARNING "Unexpected merge points\n"); | |
1128 | ret = -EINVAL; | |
1129 | } | |
1130 | } | |
1131 | kfree(mp_table); | |
1132 | return ret; | |
1133 | } |