1 #include <dirent.h>
2 #include <errno.h>
3 #include <stdlib.h>
4 #include <stdio.h>
5 #include <string.h>
6 #include <sys/types.h>
7 #include <sys/stat.h>
8 #include <sys/param.h>
9 #include <fcntl.h>
10 #include <unistd.h>
11 #include <inttypes.h>
12 #include "build-id.h"
13 #include "util.h"
14 #include "debug.h"
15 #include "machine.h"
16 #include "symbol.h"
17 #include "strlist.h"
18 
19 #include <elf.h>
20 #include <limits.h>
21 #include <sys/utsname.h>
22 
23 #ifndef KSYM_NAME_LEN
24 #define KSYM_NAME_LEN 256
25 #endif
26 
27 static int dso__load_kernel_sym(struct dso *dso, struct map *map,
28 				symbol_filter_t filter);
29 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map,
30 			symbol_filter_t filter);
31 int vmlinux_path__nr_entries;
32 char **vmlinux_path;
33 
34 struct symbol_conf symbol_conf = {
35 	.use_modules	  = true,
36 	.try_vmlinux_path = true,
37 	.annotate_src	  = true,
38 	.demangle	  = true,
39 	.symfs            = "",
40 };
41 
42 static enum dso_binary_type binary_type_symtab[] = {
43 	DSO_BINARY_TYPE__KALLSYMS,
44 	DSO_BINARY_TYPE__GUEST_KALLSYMS,
45 	DSO_BINARY_TYPE__JAVA_JIT,
46 	DSO_BINARY_TYPE__DEBUGLINK,
47 	DSO_BINARY_TYPE__BUILD_ID_CACHE,
48 	DSO_BINARY_TYPE__FEDORA_DEBUGINFO,
49 	DSO_BINARY_TYPE__UBUNTU_DEBUGINFO,
50 	DSO_BINARY_TYPE__BUILDID_DEBUGINFO,
51 	DSO_BINARY_TYPE__SYSTEM_PATH_DSO,
52 	DSO_BINARY_TYPE__GUEST_KMODULE,
53 	DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE,
54 	DSO_BINARY_TYPE__NOT_FOUND,
55 };
56 
57 #define DSO_BINARY_TYPE__SYMTAB_CNT ARRAY_SIZE(binary_type_symtab)
58 
symbol_type__is_a(char symbol_type,enum map_type map_type)59 bool symbol_type__is_a(char symbol_type, enum map_type map_type)
60 {
61 	symbol_type = toupper(symbol_type);
62 
63 	switch (map_type) {
64 	case MAP__FUNCTION:
65 		return symbol_type == 'T' || symbol_type == 'W';
66 	case MAP__VARIABLE:
67 		return symbol_type == 'D';
68 	default:
69 		return false;
70 	}
71 }
72 
prefix_underscores_count(const char * str)73 static int prefix_underscores_count(const char *str)
74 {
75 	const char *tail = str;
76 
77 	while (*tail == '_')
78 		tail++;
79 
80 	return tail - str;
81 }
82 
83 #define SYMBOL_A 0
84 #define SYMBOL_B 1
85 
choose_best_symbol(struct symbol * syma,struct symbol * symb)86 static int choose_best_symbol(struct symbol *syma, struct symbol *symb)
87 {
88 	s64 a;
89 	s64 b;
90 	size_t na, nb;
91 
92 	/* Prefer a symbol with non zero length */
93 	a = syma->end - syma->start;
94 	b = symb->end - symb->start;
95 	if ((b == 0) && (a > 0))
96 		return SYMBOL_A;
97 	else if ((a == 0) && (b > 0))
98 		return SYMBOL_B;
99 
100 	/* Prefer a non weak symbol over a weak one */
101 	a = syma->binding == STB_WEAK;
102 	b = symb->binding == STB_WEAK;
103 	if (b && !a)
104 		return SYMBOL_A;
105 	if (a && !b)
106 		return SYMBOL_B;
107 
108 	/* Prefer a global symbol over a non global one */
109 	a = syma->binding == STB_GLOBAL;
110 	b = symb->binding == STB_GLOBAL;
111 	if (a && !b)
112 		return SYMBOL_A;
113 	if (b && !a)
114 		return SYMBOL_B;
115 
116 	/* Prefer a symbol with less underscores */
117 	a = prefix_underscores_count(syma->name);
118 	b = prefix_underscores_count(symb->name);
119 	if (b > a)
120 		return SYMBOL_A;
121 	else if (a > b)
122 		return SYMBOL_B;
123 
124 	/* Choose the symbol with the longest name */
125 	na = strlen(syma->name);
126 	nb = strlen(symb->name);
127 	if (na > nb)
128 		return SYMBOL_A;
129 	else if (na < nb)
130 		return SYMBOL_B;
131 
132 	/* Avoid "SyS" kernel syscall aliases */
133 	if (na >= 3 && !strncmp(syma->name, "SyS", 3))
134 		return SYMBOL_B;
135 	if (na >= 10 && !strncmp(syma->name, "compat_SyS", 10))
136 		return SYMBOL_B;
137 
138 	return SYMBOL_A;
139 }
140 
symbols__fixup_duplicate(struct rb_root * symbols)141 void symbols__fixup_duplicate(struct rb_root *symbols)
142 {
143 	struct rb_node *nd;
144 	struct symbol *curr, *next;
145 
146 	nd = rb_first(symbols);
147 
148 	while (nd) {
149 		curr = rb_entry(nd, struct symbol, rb_node);
150 again:
151 		nd = rb_next(&curr->rb_node);
152 		next = rb_entry(nd, struct symbol, rb_node);
153 
154 		if (!nd)
155 			break;
156 
157 		if (curr->start != next->start)
158 			continue;
159 
160 		if (choose_best_symbol(curr, next) == SYMBOL_A) {
161 			rb_erase(&next->rb_node, symbols);
162 			goto again;
163 		} else {
164 			nd = rb_next(&curr->rb_node);
165 			rb_erase(&curr->rb_node, symbols);
166 		}
167 	}
168 }
169 
symbols__fixup_end(struct rb_root * symbols)170 void symbols__fixup_end(struct rb_root *symbols)
171 {
172 	struct rb_node *nd, *prevnd = rb_first(symbols);
173 	struct symbol *curr, *prev;
174 
175 	if (prevnd == NULL)
176 		return;
177 
178 	curr = rb_entry(prevnd, struct symbol, rb_node);
179 
180 	for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
181 		prev = curr;
182 		curr = rb_entry(nd, struct symbol, rb_node);
183 
184 		if (prev->end == prev->start && prev->end != curr->start)
185 			prev->end = curr->start - 1;
186 	}
187 
188 	/* Last entry */
189 	if (curr->end == curr->start)
190 		curr->end = roundup(curr->start, 4096);
191 }
192 
__map_groups__fixup_end(struct map_groups * mg,enum map_type type)193 void __map_groups__fixup_end(struct map_groups *mg, enum map_type type)
194 {
195 	struct map *prev, *curr;
196 	struct rb_node *nd, *prevnd = rb_first(&mg->maps[type]);
197 
198 	if (prevnd == NULL)
199 		return;
200 
201 	curr = rb_entry(prevnd, struct map, rb_node);
202 
203 	for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
204 		prev = curr;
205 		curr = rb_entry(nd, struct map, rb_node);
206 		prev->end = curr->start - 1;
207 	}
208 
209 	/*
210 	 * We still haven't the actual symbols, so guess the
211 	 * last map final address.
212 	 */
213 	curr->end = ~0ULL;
214 }
215 
symbol__new(u64 start,u64 len,u8 binding,const char * name)216 struct symbol *symbol__new(u64 start, u64 len, u8 binding, const char *name)
217 {
218 	size_t namelen = strlen(name) + 1;
219 	struct symbol *sym = calloc(1, (symbol_conf.priv_size +
220 					sizeof(*sym) + namelen));
221 	if (sym == NULL)
222 		return NULL;
223 
224 	if (symbol_conf.priv_size)
225 		sym = ((void *)sym) + symbol_conf.priv_size;
226 
227 	sym->start   = start;
228 	sym->end     = len ? start + len - 1 : start;
229 	sym->binding = binding;
230 	sym->namelen = namelen - 1;
231 
232 	pr_debug4("%s: %s %#" PRIx64 "-%#" PRIx64 "\n",
233 		  __func__, name, start, sym->end);
234 	memcpy(sym->name, name, namelen);
235 
236 	return sym;
237 }
238 
symbol__delete(struct symbol * sym)239 void symbol__delete(struct symbol *sym)
240 {
241 	free(((void *)sym) - symbol_conf.priv_size);
242 }
243 
symbol__fprintf(struct symbol * sym,FILE * fp)244 size_t symbol__fprintf(struct symbol *sym, FILE *fp)
245 {
246 	return fprintf(fp, " %" PRIx64 "-%" PRIx64 " %c %s\n",
247 		       sym->start, sym->end,
248 		       sym->binding == STB_GLOBAL ? 'g' :
249 		       sym->binding == STB_LOCAL  ? 'l' : 'w',
250 		       sym->name);
251 }
252 
symbol__fprintf_symname_offs(const struct symbol * sym,const struct addr_location * al,FILE * fp)253 size_t symbol__fprintf_symname_offs(const struct symbol *sym,
254 				    const struct addr_location *al, FILE *fp)
255 {
256 	unsigned long offset;
257 	size_t length;
258 
259 	if (sym && sym->name) {
260 		length = fprintf(fp, "%s", sym->name);
261 		if (al) {
262 			if (al->addr < sym->end)
263 				offset = al->addr - sym->start;
264 			else
265 				offset = al->addr - al->map->start - sym->start;
266 			length += fprintf(fp, "+0x%lx", offset);
267 		}
268 		return length;
269 	} else
270 		return fprintf(fp, "[unknown]");
271 }
272 
symbol__fprintf_symname(const struct symbol * sym,FILE * fp)273 size_t symbol__fprintf_symname(const struct symbol *sym, FILE *fp)
274 {
275 	return symbol__fprintf_symname_offs(sym, NULL, fp);
276 }
277 
symbols__delete(struct rb_root * symbols)278 void symbols__delete(struct rb_root *symbols)
279 {
280 	struct symbol *pos;
281 	struct rb_node *next = rb_first(symbols);
282 
283 	while (next) {
284 		pos = rb_entry(next, struct symbol, rb_node);
285 		next = rb_next(&pos->rb_node);
286 		rb_erase(&pos->rb_node, symbols);
287 		symbol__delete(pos);
288 	}
289 }
290 
symbols__insert(struct rb_root * symbols,struct symbol * sym)291 void symbols__insert(struct rb_root *symbols, struct symbol *sym)
292 {
293 	struct rb_node **p = &symbols->rb_node;
294 	struct rb_node *parent = NULL;
295 	const u64 ip = sym->start;
296 	struct symbol *s;
297 
298 	while (*p != NULL) {
299 		parent = *p;
300 		s = rb_entry(parent, struct symbol, rb_node);
301 		if (ip < s->start)
302 			p = &(*p)->rb_left;
303 		else
304 			p = &(*p)->rb_right;
305 	}
306 	rb_link_node(&sym->rb_node, parent, p);
307 	rb_insert_color(&sym->rb_node, symbols);
308 }
309 
symbols__find(struct rb_root * symbols,u64 ip)310 static struct symbol *symbols__find(struct rb_root *symbols, u64 ip)
311 {
312 	struct rb_node *n;
313 
314 	if (symbols == NULL)
315 		return NULL;
316 
317 	n = symbols->rb_node;
318 
319 	while (n) {
320 		struct symbol *s = rb_entry(n, struct symbol, rb_node);
321 
322 		if (ip < s->start)
323 			n = n->rb_left;
324 		else if (ip > s->end)
325 			n = n->rb_right;
326 		else
327 			return s;
328 	}
329 
330 	return NULL;
331 }
332 
symbols__first(struct rb_root * symbols)333 static struct symbol *symbols__first(struct rb_root *symbols)
334 {
335 	struct rb_node *n = rb_first(symbols);
336 
337 	if (n)
338 		return rb_entry(n, struct symbol, rb_node);
339 
340 	return NULL;
341 }
342 
343 struct symbol_name_rb_node {
344 	struct rb_node	rb_node;
345 	struct symbol	sym;
346 };
347 
symbols__insert_by_name(struct rb_root * symbols,struct symbol * sym)348 static void symbols__insert_by_name(struct rb_root *symbols, struct symbol *sym)
349 {
350 	struct rb_node **p = &symbols->rb_node;
351 	struct rb_node *parent = NULL;
352 	struct symbol_name_rb_node *symn, *s;
353 
354 	symn = container_of(sym, struct symbol_name_rb_node, sym);
355 
356 	while (*p != NULL) {
357 		parent = *p;
358 		s = rb_entry(parent, struct symbol_name_rb_node, rb_node);
359 		if (strcmp(sym->name, s->sym.name) < 0)
360 			p = &(*p)->rb_left;
361 		else
362 			p = &(*p)->rb_right;
363 	}
364 	rb_link_node(&symn->rb_node, parent, p);
365 	rb_insert_color(&symn->rb_node, symbols);
366 }
367 
symbols__sort_by_name(struct rb_root * symbols,struct rb_root * source)368 static void symbols__sort_by_name(struct rb_root *symbols,
369 				  struct rb_root *source)
370 {
371 	struct rb_node *nd;
372 
373 	for (nd = rb_first(source); nd; nd = rb_next(nd)) {
374 		struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
375 		symbols__insert_by_name(symbols, pos);
376 	}
377 }
378 
symbols__find_by_name(struct rb_root * symbols,const char * name)379 static struct symbol *symbols__find_by_name(struct rb_root *symbols,
380 					    const char *name)
381 {
382 	struct rb_node *n;
383 
384 	if (symbols == NULL)
385 		return NULL;
386 
387 	n = symbols->rb_node;
388 
389 	while (n) {
390 		struct symbol_name_rb_node *s;
391 		int cmp;
392 
393 		s = rb_entry(n, struct symbol_name_rb_node, rb_node);
394 		cmp = strcmp(name, s->sym.name);
395 
396 		if (cmp < 0)
397 			n = n->rb_left;
398 		else if (cmp > 0)
399 			n = n->rb_right;
400 		else
401 			return &s->sym;
402 	}
403 
404 	return NULL;
405 }
406 
dso__find_symbol(struct dso * dso,enum map_type type,u64 addr)407 struct symbol *dso__find_symbol(struct dso *dso,
408 				enum map_type type, u64 addr)
409 {
410 	return symbols__find(&dso->symbols[type], addr);
411 }
412 
dso__first_symbol(struct dso * dso,enum map_type type)413 struct symbol *dso__first_symbol(struct dso *dso, enum map_type type)
414 {
415 	return symbols__first(&dso->symbols[type]);
416 }
417 
dso__find_symbol_by_name(struct dso * dso,enum map_type type,const char * name)418 struct symbol *dso__find_symbol_by_name(struct dso *dso, enum map_type type,
419 					const char *name)
420 {
421 	return symbols__find_by_name(&dso->symbol_names[type], name);
422 }
423 
dso__sort_by_name(struct dso * dso,enum map_type type)424 void dso__sort_by_name(struct dso *dso, enum map_type type)
425 {
426 	dso__set_sorted_by_name(dso, type);
427 	return symbols__sort_by_name(&dso->symbol_names[type],
428 				     &dso->symbols[type]);
429 }
430 
dso__fprintf_symbols_by_name(struct dso * dso,enum map_type type,FILE * fp)431 size_t dso__fprintf_symbols_by_name(struct dso *dso,
432 				    enum map_type type, FILE *fp)
433 {
434 	size_t ret = 0;
435 	struct rb_node *nd;
436 	struct symbol_name_rb_node *pos;
437 
438 	for (nd = rb_first(&dso->symbol_names[type]); nd; nd = rb_next(nd)) {
439 		pos = rb_entry(nd, struct symbol_name_rb_node, rb_node);
440 		fprintf(fp, "%s\n", pos->sym.name);
441 	}
442 
443 	return ret;
444 }
445 
kallsyms__parse(const char * filename,void * arg,int (* process_symbol)(void * arg,const char * name,char type,u64 start))446 int kallsyms__parse(const char *filename, void *arg,
447 		    int (*process_symbol)(void *arg, const char *name,
448 					  char type, u64 start))
449 {
450 	char *line = NULL;
451 	size_t n;
452 	int err = -1;
453 	FILE *file = fopen(filename, "r");
454 
455 	if (file == NULL)
456 		goto out_failure;
457 
458 	err = 0;
459 
460 	while (!feof(file)) {
461 		u64 start;
462 		int line_len, len;
463 		char symbol_type;
464 		char *symbol_name;
465 
466 		line_len = getline(&line, &n, file);
467 		if (line_len < 0 || !line)
468 			break;
469 
470 		line[--line_len] = '\0'; /* \n */
471 
472 		len = hex2u64(line, &start);
473 
474 		len++;
475 		if (len + 2 >= line_len)
476 			continue;
477 
478 		symbol_type = line[len];
479 		len += 2;
480 		symbol_name = line + len;
481 		len = line_len - len;
482 
483 		if (len >= KSYM_NAME_LEN) {
484 			err = -1;
485 			break;
486 		}
487 
488 		err = process_symbol(arg, symbol_name,
489 				     symbol_type, start);
490 		if (err)
491 			break;
492 	}
493 
494 	free(line);
495 	fclose(file);
496 	return err;
497 
498 out_failure:
499 	return -1;
500 }
501 
502 struct process_kallsyms_args {
503 	struct map *map;
504 	struct dso *dso;
505 };
506 
kallsyms2elf_type(char type)507 static u8 kallsyms2elf_type(char type)
508 {
509 	if (type == 'W')
510 		return STB_WEAK;
511 
512 	return isupper(type) ? STB_GLOBAL : STB_LOCAL;
513 }
514 
map__process_kallsym_symbol(void * arg,const char * name,char type,u64 start)515 static int map__process_kallsym_symbol(void *arg, const char *name,
516 				       char type, u64 start)
517 {
518 	struct symbol *sym;
519 	struct process_kallsyms_args *a = arg;
520 	struct rb_root *root = &a->dso->symbols[a->map->type];
521 
522 	if (!symbol_type__is_a(type, a->map->type))
523 		return 0;
524 
525 	/*
526 	 * module symbols are not sorted so we add all
527 	 * symbols, setting length to 0, and rely on
528 	 * symbols__fixup_end() to fix it up.
529 	 */
530 	sym = symbol__new(start, 0, kallsyms2elf_type(type), name);
531 	if (sym == NULL)
532 		return -ENOMEM;
533 	/*
534 	 * We will pass the symbols to the filter later, in
535 	 * map__split_kallsyms, when we have split the maps per module
536 	 */
537 	symbols__insert(root, sym);
538 
539 	return 0;
540 }
541 
542 /*
543  * Loads the function entries in /proc/kallsyms into kernel_map->dso,
544  * so that we can in the next step set the symbol ->end address and then
545  * call kernel_maps__split_kallsyms.
546  */
dso__load_all_kallsyms(struct dso * dso,const char * filename,struct map * map)547 static int dso__load_all_kallsyms(struct dso *dso, const char *filename,
548 				  struct map *map)
549 {
550 	struct process_kallsyms_args args = { .map = map, .dso = dso, };
551 	return kallsyms__parse(filename, &args, map__process_kallsym_symbol);
552 }
553 
dso__split_kallsyms_for_kcore(struct dso * dso,struct map * map,symbol_filter_t filter)554 static int dso__split_kallsyms_for_kcore(struct dso *dso, struct map *map,
555 					 symbol_filter_t filter)
556 {
557 	struct map_groups *kmaps = map__kmap(map)->kmaps;
558 	struct map *curr_map;
559 	struct symbol *pos;
560 	int count = 0, moved = 0;
561 	struct rb_root *root = &dso->symbols[map->type];
562 	struct rb_node *next = rb_first(root);
563 
564 	while (next) {
565 		char *module;
566 
567 		pos = rb_entry(next, struct symbol, rb_node);
568 		next = rb_next(&pos->rb_node);
569 
570 		module = strchr(pos->name, '\t');
571 		if (module)
572 			*module = '\0';
573 
574 		curr_map = map_groups__find(kmaps, map->type, pos->start);
575 
576 		if (!curr_map || (filter && filter(curr_map, pos))) {
577 			rb_erase(&pos->rb_node, root);
578 			symbol__delete(pos);
579 		} else {
580 			pos->start -= curr_map->start - curr_map->pgoff;
581 			if (pos->end)
582 				pos->end -= curr_map->start - curr_map->pgoff;
583 			if (curr_map != map) {
584 				rb_erase(&pos->rb_node, root);
585 				symbols__insert(
586 					&curr_map->dso->symbols[curr_map->type],
587 					pos);
588 				++moved;
589 			} else {
590 				++count;
591 			}
592 		}
593 	}
594 
595 	/* Symbols have been adjusted */
596 	dso->adjust_symbols = 1;
597 
598 	return count + moved;
599 }
600 
601 /*
602  * Split the symbols into maps, making sure there are no overlaps, i.e. the
603  * kernel range is broken in several maps, named [kernel].N, as we don't have
604  * the original ELF section names vmlinux have.
605  */
dso__split_kallsyms(struct dso * dso,struct map * map,symbol_filter_t filter)606 static int dso__split_kallsyms(struct dso *dso, struct map *map,
607 			       symbol_filter_t filter)
608 {
609 	struct map_groups *kmaps = map__kmap(map)->kmaps;
610 	struct machine *machine = kmaps->machine;
611 	struct map *curr_map = map;
612 	struct symbol *pos;
613 	int count = 0, moved = 0;
614 	struct rb_root *root = &dso->symbols[map->type];
615 	struct rb_node *next = rb_first(root);
616 	int kernel_range = 0;
617 
618 	while (next) {
619 		char *module;
620 
621 		pos = rb_entry(next, struct symbol, rb_node);
622 		next = rb_next(&pos->rb_node);
623 
624 		module = strchr(pos->name, '\t');
625 		if (module) {
626 			if (!symbol_conf.use_modules)
627 				goto discard_symbol;
628 
629 			*module++ = '\0';
630 
631 			if (strcmp(curr_map->dso->short_name, module)) {
632 				if (curr_map != map &&
633 				    dso->kernel == DSO_TYPE_GUEST_KERNEL &&
634 				    machine__is_default_guest(machine)) {
635 					/*
636 					 * We assume all symbols of a module are
637 					 * continuous in * kallsyms, so curr_map
638 					 * points to a module and all its
639 					 * symbols are in its kmap. Mark it as
640 					 * loaded.
641 					 */
642 					dso__set_loaded(curr_map->dso,
643 							curr_map->type);
644 				}
645 
646 				curr_map = map_groups__find_by_name(kmaps,
647 							map->type, module);
648 				if (curr_map == NULL) {
649 					pr_debug("%s/proc/{kallsyms,modules} "
650 					         "inconsistency while looking "
651 						 "for \"%s\" module!\n",
652 						 machine->root_dir, module);
653 					curr_map = map;
654 					goto discard_symbol;
655 				}
656 
657 				if (curr_map->dso->loaded &&
658 				    !machine__is_default_guest(machine))
659 					goto discard_symbol;
660 			}
661 			/*
662 			 * So that we look just like we get from .ko files,
663 			 * i.e. not prelinked, relative to map->start.
664 			 */
665 			pos->start = curr_map->map_ip(curr_map, pos->start);
666 			pos->end   = curr_map->map_ip(curr_map, pos->end);
667 		} else if (curr_map != map) {
668 			char dso_name[PATH_MAX];
669 			struct dso *ndso;
670 
671 			if (count == 0) {
672 				curr_map = map;
673 				goto filter_symbol;
674 			}
675 
676 			if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
677 				snprintf(dso_name, sizeof(dso_name),
678 					"[guest.kernel].%d",
679 					kernel_range++);
680 			else
681 				snprintf(dso_name, sizeof(dso_name),
682 					"[kernel].%d",
683 					kernel_range++);
684 
685 			ndso = dso__new(dso_name);
686 			if (ndso == NULL)
687 				return -1;
688 
689 			ndso->kernel = dso->kernel;
690 
691 			curr_map = map__new2(pos->start, ndso, map->type);
692 			if (curr_map == NULL) {
693 				dso__delete(ndso);
694 				return -1;
695 			}
696 
697 			curr_map->map_ip = curr_map->unmap_ip = identity__map_ip;
698 			map_groups__insert(kmaps, curr_map);
699 			++kernel_range;
700 		}
701 filter_symbol:
702 		if (filter && filter(curr_map, pos)) {
703 discard_symbol:		rb_erase(&pos->rb_node, root);
704 			symbol__delete(pos);
705 		} else {
706 			if (curr_map != map) {
707 				rb_erase(&pos->rb_node, root);
708 				symbols__insert(&curr_map->dso->symbols[curr_map->type], pos);
709 				++moved;
710 			} else
711 				++count;
712 		}
713 	}
714 
715 	if (curr_map != map &&
716 	    dso->kernel == DSO_TYPE_GUEST_KERNEL &&
717 	    machine__is_default_guest(kmaps->machine)) {
718 		dso__set_loaded(curr_map->dso, curr_map->type);
719 	}
720 
721 	return count + moved;
722 }
723 
symbol__restricted_filename(const char * filename,const char * restricted_filename)724 bool symbol__restricted_filename(const char *filename,
725 				 const char *restricted_filename)
726 {
727 	bool restricted = false;
728 
729 	if (symbol_conf.kptr_restrict) {
730 		char *r = realpath(filename, NULL);
731 
732 		if (r != NULL) {
733 			restricted = strcmp(r, restricted_filename) == 0;
734 			free(r);
735 			return restricted;
736 		}
737 	}
738 
739 	return restricted;
740 }
741 
742 struct kcore_mapfn_data {
743 	struct dso *dso;
744 	enum map_type type;
745 	struct list_head maps;
746 };
747 
kcore_mapfn(u64 start,u64 len,u64 pgoff,void * data)748 static int kcore_mapfn(u64 start, u64 len, u64 pgoff, void *data)
749 {
750 	struct kcore_mapfn_data *md = data;
751 	struct map *map;
752 
753 	map = map__new2(start, md->dso, md->type);
754 	if (map == NULL)
755 		return -ENOMEM;
756 
757 	map->end = map->start + len;
758 	map->pgoff = pgoff;
759 
760 	list_add(&map->node, &md->maps);
761 
762 	return 0;
763 }
764 
765 /*
766  * If kallsyms is referenced by name then we look for kcore in the same
767  * directory.
768  */
kcore_filename_from_kallsyms_filename(char * kcore_filename,const char * kallsyms_filename)769 static bool kcore_filename_from_kallsyms_filename(char *kcore_filename,
770 						  const char *kallsyms_filename)
771 {
772 	char *name;
773 
774 	strcpy(kcore_filename, kallsyms_filename);
775 	name = strrchr(kcore_filename, '/');
776 	if (!name)
777 		return false;
778 
779 	if (!strcmp(name, "/kallsyms")) {
780 		strcpy(name, "/kcore");
781 		return true;
782 	}
783 
784 	return false;
785 }
786 
dso__load_kcore(struct dso * dso,struct map * map,const char * kallsyms_filename)787 static int dso__load_kcore(struct dso *dso, struct map *map,
788 			   const char *kallsyms_filename)
789 {
790 	struct map_groups *kmaps = map__kmap(map)->kmaps;
791 	struct machine *machine = kmaps->machine;
792 	struct kcore_mapfn_data md;
793 	struct map *old_map, *new_map, *replacement_map = NULL;
794 	bool is_64_bit;
795 	int err, fd;
796 	char kcore_filename[PATH_MAX];
797 	struct symbol *sym;
798 
799 	/* This function requires that the map is the kernel map */
800 	if (map != machine->vmlinux_maps[map->type])
801 		return -EINVAL;
802 
803 	if (!kcore_filename_from_kallsyms_filename(kcore_filename,
804 						   kallsyms_filename))
805 		return -EINVAL;
806 
807 	md.dso = dso;
808 	md.type = map->type;
809 	INIT_LIST_HEAD(&md.maps);
810 
811 	fd = open(kcore_filename, O_RDONLY);
812 	if (fd < 0)
813 		return -EINVAL;
814 
815 	/* Read new maps into temporary lists */
816 	err = file__read_maps(fd, md.type == MAP__FUNCTION, kcore_mapfn, &md,
817 			      &is_64_bit);
818 	if (err)
819 		goto out_err;
820 
821 	if (list_empty(&md.maps)) {
822 		err = -EINVAL;
823 		goto out_err;
824 	}
825 
826 	/* Remove old maps */
827 	old_map = map_groups__first(kmaps, map->type);
828 	while (old_map) {
829 		struct map *next = map_groups__next(old_map);
830 
831 		if (old_map != map)
832 			map_groups__remove(kmaps, old_map);
833 		old_map = next;
834 	}
835 
836 	/* Find the kernel map using the first symbol */
837 	sym = dso__first_symbol(dso, map->type);
838 	list_for_each_entry(new_map, &md.maps, node) {
839 		if (sym && sym->start >= new_map->start &&
840 		    sym->start < new_map->end) {
841 			replacement_map = new_map;
842 			break;
843 		}
844 	}
845 
846 	if (!replacement_map)
847 		replacement_map = list_entry(md.maps.next, struct map, node);
848 
849 	/* Add new maps */
850 	while (!list_empty(&md.maps)) {
851 		new_map = list_entry(md.maps.next, struct map, node);
852 		list_del(&new_map->node);
853 		if (new_map == replacement_map) {
854 			map->start	= new_map->start;
855 			map->end	= new_map->end;
856 			map->pgoff	= new_map->pgoff;
857 			map->map_ip	= new_map->map_ip;
858 			map->unmap_ip	= new_map->unmap_ip;
859 			map__delete(new_map);
860 			/* Ensure maps are correctly ordered */
861 			map_groups__remove(kmaps, map);
862 			map_groups__insert(kmaps, map);
863 		} else {
864 			map_groups__insert(kmaps, new_map);
865 		}
866 	}
867 
868 	/*
869 	 * Set the data type and long name so that kcore can be read via
870 	 * dso__data_read_addr().
871 	 */
872 	if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
873 		dso->data_type = DSO_BINARY_TYPE__GUEST_KCORE;
874 	else
875 		dso->data_type = DSO_BINARY_TYPE__KCORE;
876 	dso__set_long_name(dso, strdup(kcore_filename));
877 
878 	close(fd);
879 
880 	if (map->type == MAP__FUNCTION)
881 		pr_debug("Using %s for kernel object code\n", kcore_filename);
882 	else
883 		pr_debug("Using %s for kernel data\n", kcore_filename);
884 
885 	return 0;
886 
887 out_err:
888 	while (!list_empty(&md.maps)) {
889 		map = list_entry(md.maps.next, struct map, node);
890 		list_del(&map->node);
891 		map__delete(map);
892 	}
893 	close(fd);
894 	return -EINVAL;
895 }
896 
dso__load_kallsyms(struct dso * dso,const char * filename,struct map * map,symbol_filter_t filter)897 int dso__load_kallsyms(struct dso *dso, const char *filename,
898 		       struct map *map, symbol_filter_t filter)
899 {
900 	if (symbol__restricted_filename(filename, "/proc/kallsyms"))
901 		return -1;
902 
903 	if (dso__load_all_kallsyms(dso, filename, map) < 0)
904 		return -1;
905 
906 	symbols__fixup_duplicate(&dso->symbols[map->type]);
907 	symbols__fixup_end(&dso->symbols[map->type]);
908 
909 	if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
910 		dso->symtab_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
911 	else
912 		dso->symtab_type = DSO_BINARY_TYPE__KALLSYMS;
913 
914 	if (!dso__load_kcore(dso, map, filename))
915 		return dso__split_kallsyms_for_kcore(dso, map, filter);
916 	else
917 		return dso__split_kallsyms(dso, map, filter);
918 }
919 
dso__load_perf_map(struct dso * dso,struct map * map,symbol_filter_t filter)920 static int dso__load_perf_map(struct dso *dso, struct map *map,
921 			      symbol_filter_t filter)
922 {
923 	char *line = NULL;
924 	size_t n;
925 	FILE *file;
926 	int nr_syms = 0;
927 
928 	file = fopen(dso->long_name, "r");
929 	if (file == NULL)
930 		goto out_failure;
931 
932 	while (!feof(file)) {
933 		u64 start, size;
934 		struct symbol *sym;
935 		int line_len, len;
936 
937 		line_len = getline(&line, &n, file);
938 		if (line_len < 0)
939 			break;
940 
941 		if (!line)
942 			goto out_failure;
943 
944 		line[--line_len] = '\0'; /* \n */
945 
946 		len = hex2u64(line, &start);
947 
948 		len++;
949 		if (len + 2 >= line_len)
950 			continue;
951 
952 		len += hex2u64(line + len, &size);
953 
954 		len++;
955 		if (len + 2 >= line_len)
956 			continue;
957 
958 		sym = symbol__new(start, size, STB_GLOBAL, line + len);
959 
960 		if (sym == NULL)
961 			goto out_delete_line;
962 
963 		if (filter && filter(map, sym))
964 			symbol__delete(sym);
965 		else {
966 			symbols__insert(&dso->symbols[map->type], sym);
967 			nr_syms++;
968 		}
969 	}
970 
971 	free(line);
972 	fclose(file);
973 
974 	return nr_syms;
975 
976 out_delete_line:
977 	free(line);
978 out_failure:
979 	return -1;
980 }
981 
dso__load(struct dso * dso,struct map * map,symbol_filter_t filter)982 int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter)
983 {
984 	char *name;
985 	int ret = -1;
986 	u_int i;
987 	struct machine *machine;
988 	char *root_dir = (char *) "";
989 	int ss_pos = 0;
990 	struct symsrc ss_[2];
991 	struct symsrc *syms_ss = NULL, *runtime_ss = NULL;
992 
993 	dso__set_loaded(dso, map->type);
994 
995 	if (dso->kernel == DSO_TYPE_KERNEL)
996 		return dso__load_kernel_sym(dso, map, filter);
997 	else if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
998 		return dso__load_guest_kernel_sym(dso, map, filter);
999 
1000 	if (map->groups && map->groups->machine)
1001 		machine = map->groups->machine;
1002 	else
1003 		machine = NULL;
1004 
1005 	dso->adjust_symbols = 0;
1006 
1007 	if (strncmp(dso->name, "/tmp/perf-", 10) == 0) {
1008 		struct stat st;
1009 
1010 		if (lstat(dso->name, &st) < 0)
1011 			return -1;
1012 
1013 		if (st.st_uid && (st.st_uid != geteuid())) {
1014 			pr_warning("File %s not owned by current user or root, "
1015 				"ignoring it.\n", dso->name);
1016 			return -1;
1017 		}
1018 
1019 		ret = dso__load_perf_map(dso, map, filter);
1020 		dso->symtab_type = ret > 0 ? DSO_BINARY_TYPE__JAVA_JIT :
1021 					     DSO_BINARY_TYPE__NOT_FOUND;
1022 		return ret;
1023 	}
1024 
1025 	if (machine)
1026 		root_dir = machine->root_dir;
1027 
1028 	name = malloc(PATH_MAX);
1029 	if (!name)
1030 		return -1;
1031 
1032 	/* Iterate over candidate debug images.
1033 	 * Keep track of "interesting" ones (those which have a symtab, dynsym,
1034 	 * and/or opd section) for processing.
1035 	 */
1036 	for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) {
1037 		struct symsrc *ss = &ss_[ss_pos];
1038 		bool next_slot = false;
1039 
1040 		enum dso_binary_type symtab_type = binary_type_symtab[i];
1041 
1042 		if (dso__binary_type_file(dso, symtab_type,
1043 					  root_dir, name, PATH_MAX))
1044 			continue;
1045 
1046 		/* Name is now the name of the next image to try */
1047 		if (symsrc__init(ss, dso, name, symtab_type) < 0)
1048 			continue;
1049 
1050 		if (!syms_ss && symsrc__has_symtab(ss)) {
1051 			syms_ss = ss;
1052 			next_slot = true;
1053 		}
1054 
1055 		if (!runtime_ss && symsrc__possibly_runtime(ss)) {
1056 			runtime_ss = ss;
1057 			next_slot = true;
1058 		}
1059 
1060 		if (next_slot) {
1061 			ss_pos++;
1062 
1063 			if (syms_ss && runtime_ss)
1064 				break;
1065 		}
1066 
1067 	}
1068 
1069 	if (!runtime_ss && !syms_ss)
1070 		goto out_free;
1071 
1072 	if (runtime_ss && !syms_ss) {
1073 		syms_ss = runtime_ss;
1074 	}
1075 
1076 	/* We'll have to hope for the best */
1077 	if (!runtime_ss && syms_ss)
1078 		runtime_ss = syms_ss;
1079 
1080 	if (syms_ss) {
1081 		int km;
1082 
1083 		km = dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE ||
1084 		     dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE;
1085 		ret = dso__load_sym(dso, map, syms_ss, runtime_ss, filter, km);
1086 	} else {
1087 		ret = -1;
1088 	}
1089 
1090 	if (ret > 0) {
1091 		int nr_plt;
1092 
1093 		nr_plt = dso__synthesize_plt_symbols(dso, runtime_ss, map, filter);
1094 		if (nr_plt > 0)
1095 			ret += nr_plt;
1096 	}
1097 
1098 	for (; ss_pos > 0; ss_pos--)
1099 		symsrc__destroy(&ss_[ss_pos - 1]);
1100 out_free:
1101 	free(name);
1102 	if (ret < 0 && strstr(dso->name, " (deleted)") != NULL)
1103 		return 0;
1104 	return ret;
1105 }
1106 
map_groups__find_by_name(struct map_groups * mg,enum map_type type,const char * name)1107 struct map *map_groups__find_by_name(struct map_groups *mg,
1108 				     enum map_type type, const char *name)
1109 {
1110 	struct rb_node *nd;
1111 
1112 	for (nd = rb_first(&mg->maps[type]); nd; nd = rb_next(nd)) {
1113 		struct map *map = rb_entry(nd, struct map, rb_node);
1114 
1115 		if (map->dso && strcmp(map->dso->short_name, name) == 0)
1116 			return map;
1117 	}
1118 
1119 	return NULL;
1120 }
1121 
dso__load_vmlinux(struct dso * dso,struct map * map,const char * vmlinux,symbol_filter_t filter)1122 int dso__load_vmlinux(struct dso *dso, struct map *map,
1123 		      const char *vmlinux, symbol_filter_t filter)
1124 {
1125 	int err = -1;
1126 	struct symsrc ss;
1127 	char symfs_vmlinux[PATH_MAX];
1128 	enum dso_binary_type symtab_type;
1129 
1130 	if (vmlinux[0] == '/')
1131 		snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s", vmlinux);
1132 	else
1133 		snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s%s",
1134 			 symbol_conf.symfs, vmlinux);
1135 
1136 	if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1137 		symtab_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
1138 	else
1139 		symtab_type = DSO_BINARY_TYPE__VMLINUX;
1140 
1141 	if (symsrc__init(&ss, dso, symfs_vmlinux, symtab_type))
1142 		return -1;
1143 
1144 	err = dso__load_sym(dso, map, &ss, &ss, filter, 0);
1145 	symsrc__destroy(&ss);
1146 
1147 	if (err > 0) {
1148 		if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1149 			dso->data_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
1150 		else
1151 			dso->data_type = DSO_BINARY_TYPE__VMLINUX;
1152 		dso__set_long_name(dso, (char *)vmlinux);
1153 		dso__set_loaded(dso, map->type);
1154 		pr_debug("Using %s for symbols\n", symfs_vmlinux);
1155 	}
1156 
1157 	return err;
1158 }
1159 
dso__load_vmlinux_path(struct dso * dso,struct map * map,symbol_filter_t filter)1160 int dso__load_vmlinux_path(struct dso *dso, struct map *map,
1161 			   symbol_filter_t filter)
1162 {
1163 	int i, err = 0;
1164 	char *filename;
1165 
1166 	pr_debug("Looking at the vmlinux_path (%d entries long)\n",
1167 		 vmlinux_path__nr_entries + 1);
1168 
1169 	filename = dso__build_id_filename(dso, NULL, 0);
1170 	if (filename != NULL) {
1171 		err = dso__load_vmlinux(dso, map, filename, filter);
1172 		if (err > 0) {
1173 			dso->lname_alloc = 1;
1174 			goto out;
1175 		}
1176 		free(filename);
1177 	}
1178 
1179 	for (i = 0; i < vmlinux_path__nr_entries; ++i) {
1180 		err = dso__load_vmlinux(dso, map, vmlinux_path[i], filter);
1181 		if (err > 0) {
1182 			dso__set_long_name(dso, strdup(vmlinux_path[i]));
1183 			dso->lname_alloc = 1;
1184 			break;
1185 		}
1186 	}
1187 out:
1188 	return err;
1189 }
1190 
dso__load_kernel_sym(struct dso * dso,struct map * map,symbol_filter_t filter)1191 static int dso__load_kernel_sym(struct dso *dso, struct map *map,
1192 				symbol_filter_t filter)
1193 {
1194 	int err;
1195 	const char *kallsyms_filename = NULL;
1196 	char *kallsyms_allocated_filename = NULL;
1197 	/*
1198 	 * Step 1: if the user specified a kallsyms or vmlinux filename, use
1199 	 * it and only it, reporting errors to the user if it cannot be used.
1200 	 *
1201 	 * For instance, try to analyse an ARM perf.data file _without_ a
1202 	 * build-id, or if the user specifies the wrong path to the right
1203 	 * vmlinux file, obviously we can't fallback to another vmlinux (a
1204 	 * x86_86 one, on the machine where analysis is being performed, say),
1205 	 * or worse, /proc/kallsyms.
1206 	 *
1207 	 * If the specified file _has_ a build-id and there is a build-id
1208 	 * section in the perf.data file, we will still do the expected
1209 	 * validation in dso__load_vmlinux and will bail out if they don't
1210 	 * match.
1211 	 */
1212 	if (symbol_conf.kallsyms_name != NULL) {
1213 		kallsyms_filename = symbol_conf.kallsyms_name;
1214 		goto do_kallsyms;
1215 	}
1216 
1217 	if (symbol_conf.vmlinux_name != NULL) {
1218 		err = dso__load_vmlinux(dso, map,
1219 					symbol_conf.vmlinux_name, filter);
1220 		if (err > 0) {
1221 			dso__set_long_name(dso,
1222 					   strdup(symbol_conf.vmlinux_name));
1223 			dso->lname_alloc = 1;
1224 			return err;
1225 		}
1226 		return err;
1227 	}
1228 
1229 	if (vmlinux_path != NULL) {
1230 		err = dso__load_vmlinux_path(dso, map, filter);
1231 		if (err > 0)
1232 			return err;
1233 	}
1234 
1235 	/* do not try local files if a symfs was given */
1236 	if (symbol_conf.symfs[0] != 0)
1237 		return -1;
1238 
1239 	/*
1240 	 * Say the kernel DSO was created when processing the build-id header table,
1241 	 * we have a build-id, so check if it is the same as the running kernel,
1242 	 * using it if it is.
1243 	 */
1244 	if (dso->has_build_id) {
1245 		u8 kallsyms_build_id[BUILD_ID_SIZE];
1246 		char sbuild_id[BUILD_ID_SIZE * 2 + 1];
1247 
1248 		if (sysfs__read_build_id("/sys/kernel/notes", kallsyms_build_id,
1249 					 sizeof(kallsyms_build_id)) == 0) {
1250 			if (dso__build_id_equal(dso, kallsyms_build_id)) {
1251 				kallsyms_filename = "/proc/kallsyms";
1252 				goto do_kallsyms;
1253 			}
1254 		}
1255 		/*
1256 		 * Now look if we have it on the build-id cache in
1257 		 * $HOME/.debug/[kernel.kallsyms].
1258 		 */
1259 		build_id__sprintf(dso->build_id, sizeof(dso->build_id),
1260 				  sbuild_id);
1261 
1262 		if (asprintf(&kallsyms_allocated_filename,
1263 			     "%s/.debug/[kernel.kallsyms]/%s",
1264 			     getenv("HOME"), sbuild_id) == -1) {
1265 			pr_err("Not enough memory for kallsyms file lookup\n");
1266 			return -1;
1267 		}
1268 
1269 		kallsyms_filename = kallsyms_allocated_filename;
1270 
1271 		if (access(kallsyms_filename, F_OK)) {
1272 			pr_err("No kallsyms or vmlinux with build-id %s "
1273 			       "was found\n", sbuild_id);
1274 			free(kallsyms_allocated_filename);
1275 			return -1;
1276 		}
1277 	} else {
1278 		/*
1279 		 * Last resort, if we don't have a build-id and couldn't find
1280 		 * any vmlinux file, try the running kernel kallsyms table.
1281 		 */
1282 		kallsyms_filename = "/proc/kallsyms";
1283 	}
1284 
1285 do_kallsyms:
1286 	err = dso__load_kallsyms(dso, kallsyms_filename, map, filter);
1287 	if (err > 0)
1288 		pr_debug("Using %s for symbols\n", kallsyms_filename);
1289 	free(kallsyms_allocated_filename);
1290 
1291 	if (err > 0 && !dso__is_kcore(dso)) {
1292 		dso__set_long_name(dso, strdup("[kernel.kallsyms]"));
1293 		map__fixup_start(map);
1294 		map__fixup_end(map);
1295 	}
1296 
1297 	return err;
1298 }
1299 
dso__load_guest_kernel_sym(struct dso * dso,struct map * map,symbol_filter_t filter)1300 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map,
1301 				      symbol_filter_t filter)
1302 {
1303 	int err;
1304 	const char *kallsyms_filename = NULL;
1305 	struct machine *machine;
1306 	char path[PATH_MAX];
1307 
1308 	if (!map->groups) {
1309 		pr_debug("Guest kernel map hasn't the point to groups\n");
1310 		return -1;
1311 	}
1312 	machine = map->groups->machine;
1313 
1314 	if (machine__is_default_guest(machine)) {
1315 		/*
1316 		 * if the user specified a vmlinux filename, use it and only
1317 		 * it, reporting errors to the user if it cannot be used.
1318 		 * Or use file guest_kallsyms inputted by user on commandline
1319 		 */
1320 		if (symbol_conf.default_guest_vmlinux_name != NULL) {
1321 			err = dso__load_vmlinux(dso, map,
1322 				symbol_conf.default_guest_vmlinux_name, filter);
1323 			return err;
1324 		}
1325 
1326 		kallsyms_filename = symbol_conf.default_guest_kallsyms;
1327 		if (!kallsyms_filename)
1328 			return -1;
1329 	} else {
1330 		sprintf(path, "%s/proc/kallsyms", machine->root_dir);
1331 		kallsyms_filename = path;
1332 	}
1333 
1334 	err = dso__load_kallsyms(dso, kallsyms_filename, map, filter);
1335 	if (err > 0)
1336 		pr_debug("Using %s for symbols\n", kallsyms_filename);
1337 	if (err > 0 && !dso__is_kcore(dso)) {
1338 		machine__mmap_name(machine, path, sizeof(path));
1339 		dso__set_long_name(dso, strdup(path));
1340 		map__fixup_start(map);
1341 		map__fixup_end(map);
1342 	}
1343 
1344 	return err;
1345 }
1346 
vmlinux_path__exit(void)1347 static void vmlinux_path__exit(void)
1348 {
1349 	while (--vmlinux_path__nr_entries >= 0) {
1350 		free(vmlinux_path[vmlinux_path__nr_entries]);
1351 		vmlinux_path[vmlinux_path__nr_entries] = NULL;
1352 	}
1353 
1354 	free(vmlinux_path);
1355 	vmlinux_path = NULL;
1356 }
1357 
vmlinux_path__init(void)1358 static int vmlinux_path__init(void)
1359 {
1360 	struct utsname uts;
1361 	char bf[PATH_MAX];
1362 
1363 	vmlinux_path = malloc(sizeof(char *) * 5);
1364 	if (vmlinux_path == NULL)
1365 		return -1;
1366 
1367 	vmlinux_path[vmlinux_path__nr_entries] = strdup("vmlinux");
1368 	if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1369 		goto out_fail;
1370 	++vmlinux_path__nr_entries;
1371 	vmlinux_path[vmlinux_path__nr_entries] = strdup("/boot/vmlinux");
1372 	if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1373 		goto out_fail;
1374 	++vmlinux_path__nr_entries;
1375 
1376 	/* only try running kernel version if no symfs was given */
1377 	if (symbol_conf.symfs[0] != 0)
1378 		return 0;
1379 
1380 	if (uname(&uts) < 0)
1381 		return -1;
1382 
1383 	snprintf(bf, sizeof(bf), "/boot/vmlinux-%s", uts.release);
1384 	vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
1385 	if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1386 		goto out_fail;
1387 	++vmlinux_path__nr_entries;
1388 	snprintf(bf, sizeof(bf), "/lib/modules/%s/build/vmlinux", uts.release);
1389 	vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
1390 	if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1391 		goto out_fail;
1392 	++vmlinux_path__nr_entries;
1393 	snprintf(bf, sizeof(bf), "/usr/lib/debug/lib/modules/%s/vmlinux",
1394 		 uts.release);
1395 	vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
1396 	if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1397 		goto out_fail;
1398 	++vmlinux_path__nr_entries;
1399 
1400 	return 0;
1401 
1402 out_fail:
1403 	vmlinux_path__exit();
1404 	return -1;
1405 }
1406 
setup_list(struct strlist ** list,const char * list_str,const char * list_name)1407 static int setup_list(struct strlist **list, const char *list_str,
1408 		      const char *list_name)
1409 {
1410 	if (list_str == NULL)
1411 		return 0;
1412 
1413 	*list = strlist__new(true, list_str);
1414 	if (!*list) {
1415 		pr_err("problems parsing %s list\n", list_name);
1416 		return -1;
1417 	}
1418 	return 0;
1419 }
1420 
symbol__read_kptr_restrict(void)1421 static bool symbol__read_kptr_restrict(void)
1422 {
1423 	bool value = false;
1424 
1425 	if (geteuid() != 0) {
1426 		FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r");
1427 		if (fp != NULL) {
1428 			char line[8];
1429 
1430 			if (fgets(line, sizeof(line), fp) != NULL)
1431 				value = atoi(line) != 0;
1432 
1433 			fclose(fp);
1434 		}
1435 	}
1436 
1437 	return value;
1438 }
1439 
symbol__init(void)1440 int symbol__init(void)
1441 {
1442 	const char *symfs;
1443 
1444 	if (symbol_conf.initialized)
1445 		return 0;
1446 
1447 	symbol_conf.priv_size = PERF_ALIGN(symbol_conf.priv_size, sizeof(u64));
1448 
1449 	symbol__elf_init();
1450 
1451 	if (symbol_conf.sort_by_name)
1452 		symbol_conf.priv_size += (sizeof(struct symbol_name_rb_node) -
1453 					  sizeof(struct symbol));
1454 
1455 	if (symbol_conf.try_vmlinux_path && vmlinux_path__init() < 0)
1456 		return -1;
1457 
1458 	if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') {
1459 		pr_err("'.' is the only non valid --field-separator argument\n");
1460 		return -1;
1461 	}
1462 
1463 	if (setup_list(&symbol_conf.dso_list,
1464 		       symbol_conf.dso_list_str, "dso") < 0)
1465 		return -1;
1466 
1467 	if (setup_list(&symbol_conf.comm_list,
1468 		       symbol_conf.comm_list_str, "comm") < 0)
1469 		goto out_free_dso_list;
1470 
1471 	if (setup_list(&symbol_conf.sym_list,
1472 		       symbol_conf.sym_list_str, "symbol") < 0)
1473 		goto out_free_comm_list;
1474 
1475 	/*
1476 	 * A path to symbols of "/" is identical to ""
1477 	 * reset here for simplicity.
1478 	 */
1479 	symfs = realpath(symbol_conf.symfs, NULL);
1480 	if (symfs == NULL)
1481 		symfs = symbol_conf.symfs;
1482 	if (strcmp(symfs, "/") == 0)
1483 		symbol_conf.symfs = "";
1484 	if (symfs != symbol_conf.symfs)
1485 		free((void *)symfs);
1486 
1487 	symbol_conf.kptr_restrict = symbol__read_kptr_restrict();
1488 
1489 	symbol_conf.initialized = true;
1490 	return 0;
1491 
1492 out_free_comm_list:
1493 	strlist__delete(symbol_conf.comm_list);
1494 out_free_dso_list:
1495 	strlist__delete(symbol_conf.dso_list);
1496 	return -1;
1497 }
1498 
symbol__exit(void)1499 void symbol__exit(void)
1500 {
1501 	if (!symbol_conf.initialized)
1502 		return;
1503 	strlist__delete(symbol_conf.sym_list);
1504 	strlist__delete(symbol_conf.dso_list);
1505 	strlist__delete(symbol_conf.comm_list);
1506 	vmlinux_path__exit();
1507 	symbol_conf.sym_list = symbol_conf.dso_list = symbol_conf.comm_list = NULL;
1508 	symbol_conf.initialized = false;
1509 }
1510