1
2#include <fcntl.h>
3#include <stdio.h>
4#include <errno.h>
5#include <stdlib.h>
6#include <string.h>
7#include <unistd.h>
8#include <inttypes.h>
9
10#include "dso.h"
11#include "map.h"
12#include "maps.h"
13#include "symbol.h"
14#include "symsrc.h"
15#include "demangle-ocaml.h"
16#include "demangle-java.h"
17#include "demangle-rust.h"
18#include "machine.h"
19#include "vdso.h"
20#include "debug.h"
21#include "util/copyfile.h"
22#include <linux/ctype.h>
23#include <linux/kernel.h>
24#include <linux/zalloc.h>
25#include <symbol/kallsyms.h>
26#include <internal/lib.h>
27
28#ifndef EM_AARCH64
29#define EM_AARCH64 183
30#endif
31
32#ifndef ELF32_ST_VISIBILITY
33#define ELF32_ST_VISIBILITY(o) ((o) & 0x03)
34#endif
35
36
37#ifndef ELF64_ST_VISIBILITY
38#define ELF64_ST_VISIBILITY(o) ELF32_ST_VISIBILITY (o)
39#endif
40
41
42#ifndef GELF_ST_VISIBILITY
43#define GELF_ST_VISIBILITY(val) ELF64_ST_VISIBILITY (val)
44#endif
45
46typedef Elf64_Nhdr GElf_Nhdr;
47
48#ifndef DMGL_PARAMS
49#define DMGL_NO_OPTS 0
50#define DMGL_PARAMS (1 << 0)
51#define DMGL_ANSI (1 << 1)
52#endif
53
54#ifdef HAVE_LIBBFD_SUPPORT
55#define PACKAGE 'perf'
56#include <bfd.h>
57#else
58#ifdef HAVE_CPLUS_DEMANGLE_SUPPORT
59extern char *cplus_demangle(const char *, int);
60
61static inline char *bfd_demangle(void __maybe_unused *v, const char *c, int i)
62{
63 return cplus_demangle(c, i);
64}
65#else
66#ifdef NO_DEMANGLE
67static inline char *bfd_demangle(void __maybe_unused *v,
68 const char __maybe_unused *c,
69 int __maybe_unused i)
70{
71 return NULL;
72}
73#endif
74#endif
75#endif
76
77#ifndef HAVE_ELF_GETPHDRNUM_SUPPORT
78static int elf_getphdrnum(Elf *elf, size_t *dst)
79{
80 GElf_Ehdr gehdr;
81 GElf_Ehdr *ehdr;
82
83 ehdr = gelf_getehdr(elf, &gehdr);
84 if (!ehdr)
85 return -1;
86
87 *dst = ehdr->e_phnum;
88
89 return 0;
90}
91#endif
92
93#ifndef HAVE_ELF_GETSHDRSTRNDX_SUPPORT
94static int elf_getshdrstrndx(Elf *elf __maybe_unused, size_t *dst __maybe_unused)
95{
96 pr_err("%s: update your libelf to > 0.140, this one lacks elf_getshdrstrndx().\n", __func__);
97 return -1;
98}
99#endif
100
101#ifndef NT_GNU_BUILD_ID
102#define NT_GNU_BUILD_ID 3
103#endif
104
105
106
107
108
109
110
111
112#define elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) \
113 for (idx = 0, gelf_getsym(syms, idx, &sym);\
114 idx < nr_syms; \
115 idx++, gelf_getsym(syms, idx, &sym))
116
117static inline uint8_t elf_sym__type(const GElf_Sym *sym)
118{
119 return GELF_ST_TYPE(sym->st_info);
120}
121
122static inline uint8_t elf_sym__visibility(const GElf_Sym *sym)
123{
124 return GELF_ST_VISIBILITY(sym->st_other);
125}
126
127#ifndef STT_GNU_IFUNC
128#define STT_GNU_IFUNC 10
129#endif
130
131static inline int elf_sym__is_function(const GElf_Sym *sym)
132{
133 return (elf_sym__type(sym) == STT_FUNC ||
134 elf_sym__type(sym) == STT_GNU_IFUNC) &&
135 sym->st_name != 0 &&
136 sym->st_shndx != SHN_UNDEF;
137}
138
139static inline bool elf_sym__is_object(const GElf_Sym *sym)
140{
141 return elf_sym__type(sym) == STT_OBJECT &&
142 sym->st_name != 0 &&
143 sym->st_shndx != SHN_UNDEF;
144}
145
146static inline int elf_sym__is_label(const GElf_Sym *sym)
147{
148 return elf_sym__type(sym) == STT_NOTYPE &&
149 sym->st_name != 0 &&
150 sym->st_shndx != SHN_UNDEF &&
151 sym->st_shndx != SHN_ABS &&
152 elf_sym__visibility(sym) != STV_HIDDEN &&
153 elf_sym__visibility(sym) != STV_INTERNAL;
154}
155
156static bool elf_sym__filter(GElf_Sym *sym)
157{
158 return elf_sym__is_function(sym) || elf_sym__is_object(sym);
159}
160
161static inline const char *elf_sym__name(const GElf_Sym *sym,
162 const Elf_Data *symstrs)
163{
164 return symstrs->d_buf + sym->st_name;
165}
166
167static inline const char *elf_sec__name(const GElf_Shdr *shdr,
168 const Elf_Data *secstrs)
169{
170 return secstrs->d_buf + shdr->sh_name;
171}
172
173static inline int elf_sec__is_text(const GElf_Shdr *shdr,
174 const Elf_Data *secstrs)
175{
176 return strstr(elf_sec__name(shdr, secstrs), "text") != NULL;
177}
178
179static inline bool elf_sec__is_data(const GElf_Shdr *shdr,
180 const Elf_Data *secstrs)
181{
182 return strstr(elf_sec__name(shdr, secstrs), "data") != NULL;
183}
184
185static bool elf_sec__filter(GElf_Shdr *shdr, Elf_Data *secstrs)
186{
187 return elf_sec__is_text(shdr, secstrs) ||
188 elf_sec__is_data(shdr, secstrs);
189}
190
191static size_t elf_addr_to_index(Elf *elf, GElf_Addr addr)
192{
193 Elf_Scn *sec = NULL;
194 GElf_Shdr shdr;
195 size_t cnt = 1;
196
197 while ((sec = elf_nextscn(elf, sec)) != NULL) {
198 gelf_getshdr(sec, &shdr);
199
200 if ((addr >= shdr.sh_addr) &&
201 (addr < (shdr.sh_addr + shdr.sh_size)))
202 return cnt;
203
204 ++cnt;
205 }
206
207 return -1;
208}
209
210Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep,
211 GElf_Shdr *shp, const char *name, size_t *idx)
212{
213 Elf_Scn *sec = NULL;
214 size_t cnt = 1;
215
216
217 if (!elf_rawdata(elf_getscn(elf, ep->e_shstrndx), NULL))
218 return NULL;
219
220 while ((sec = elf_nextscn(elf, sec)) != NULL) {
221 char *str;
222
223 gelf_getshdr(sec, shp);
224 str = elf_strptr(elf, ep->e_shstrndx, shp->sh_name);
225 if (str && !strcmp(name, str)) {
226 if (idx)
227 *idx = cnt;
228 return sec;
229 }
230 ++cnt;
231 }
232
233 return NULL;
234}
235
236static int elf_read_program_header(Elf *elf, u64 vaddr, GElf_Phdr *phdr)
237{
238 size_t i, phdrnum;
239 u64 sz;
240
241 if (elf_getphdrnum(elf, &phdrnum))
242 return -1;
243
244 for (i = 0; i < phdrnum; i++) {
245 if (gelf_getphdr(elf, i, phdr) == NULL)
246 return -1;
247
248 if (phdr->p_type != PT_LOAD)
249 continue;
250
251 sz = max(phdr->p_memsz, phdr->p_filesz);
252 if (!sz)
253 continue;
254
255 if (vaddr >= phdr->p_vaddr && (vaddr < phdr->p_vaddr + sz))
256 return 0;
257 }
258
259
260 return -1;
261}
262
263static bool want_demangle(bool is_kernel_sym)
264{
265 return is_kernel_sym ? symbol_conf.demangle_kernel : symbol_conf.demangle;
266}
267
268static char *demangle_sym(struct dso *dso, int kmodule, const char *elf_name)
269{
270 int demangle_flags = verbose > 0 ? (DMGL_PARAMS | DMGL_ANSI) : DMGL_NO_OPTS;
271 char *demangled = NULL;
272
273
274
275
276
277
278 if (!want_demangle(dso->kernel || kmodule))
279 return demangled;
280
281 demangled = bfd_demangle(NULL, elf_name, demangle_flags);
282 if (demangled == NULL) {
283 demangled = ocaml_demangle_sym(elf_name);
284 if (demangled == NULL) {
285 demangled = java_demangle_sym(elf_name, JAVA_DEMANGLE_NORET);
286 }
287 }
288 else if (rust_is_mangled(demangled))
289
290
291
292
293 rust_demangle_sym(demangled);
294
295 return demangled;
296}
297
298#define elf_section__for_each_rel(reldata, pos, pos_mem, idx, nr_entries) \
299 for (idx = 0, pos = gelf_getrel(reldata, 0, &pos_mem); \
300 idx < nr_entries; \
301 ++idx, pos = gelf_getrel(reldata, idx, &pos_mem))
302
303#define elf_section__for_each_rela(reldata, pos, pos_mem, idx, nr_entries) \
304 for (idx = 0, pos = gelf_getrela(reldata, 0, &pos_mem); \
305 idx < nr_entries; \
306 ++idx, pos = gelf_getrela(reldata, idx, &pos_mem))
307
308
309
310
311
312
313
314
315int dso__synthesize_plt_symbols(struct dso *dso, struct symsrc *ss)
316{
317 uint32_t nr_rel_entries, idx;
318 GElf_Sym sym;
319 u64 plt_offset, plt_header_size, plt_entry_size;
320 GElf_Shdr shdr_plt;
321 struct symbol *f;
322 GElf_Shdr shdr_rel_plt, shdr_dynsym;
323 Elf_Data *reldata, *syms, *symstrs;
324 Elf_Scn *scn_plt_rel, *scn_symstrs, *scn_dynsym;
325 size_t dynsym_idx;
326 GElf_Ehdr ehdr;
327 char sympltname[1024];
328 Elf *elf;
329 int nr = 0, symidx, err = 0;
330
331 if (!ss->dynsym)
332 return 0;
333
334 elf = ss->elf;
335 ehdr = ss->ehdr;
336
337 scn_dynsym = ss->dynsym;
338 shdr_dynsym = ss->dynshdr;
339 dynsym_idx = ss->dynsym_idx;
340
341 if (scn_dynsym == NULL)
342 goto out_elf_end;
343
344 scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt,
345 ".rela.plt", NULL);
346 if (scn_plt_rel == NULL) {
347 scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt,
348 ".rel.plt", NULL);
349 if (scn_plt_rel == NULL)
350 goto out_elf_end;
351 }
352
353 err = -1;
354
355 if (shdr_rel_plt.sh_link != dynsym_idx)
356 goto out_elf_end;
357
358 if (elf_section_by_name(elf, &ehdr, &shdr_plt, ".plt", NULL) == NULL)
359 goto out_elf_end;
360
361
362
363
364
365 reldata = elf_getdata(scn_plt_rel, NULL);
366 if (reldata == NULL)
367 goto out_elf_end;
368
369 syms = elf_getdata(scn_dynsym, NULL);
370 if (syms == NULL)
371 goto out_elf_end;
372
373 scn_symstrs = elf_getscn(elf, shdr_dynsym.sh_link);
374 if (scn_symstrs == NULL)
375 goto out_elf_end;
376
377 symstrs = elf_getdata(scn_symstrs, NULL);
378 if (symstrs == NULL)
379 goto out_elf_end;
380
381 if (symstrs->d_size == 0)
382 goto out_elf_end;
383
384 nr_rel_entries = shdr_rel_plt.sh_size / shdr_rel_plt.sh_entsize;
385 plt_offset = shdr_plt.sh_offset;
386 switch (ehdr.e_machine) {
387 case EM_ARM:
388 plt_header_size = 20;
389 plt_entry_size = 12;
390 break;
391
392 case EM_AARCH64:
393 plt_header_size = 32;
394 plt_entry_size = 16;
395 break;
396
397 case EM_SPARC:
398 plt_header_size = 48;
399 plt_entry_size = 12;
400 break;
401
402 case EM_SPARCV9:
403 plt_header_size = 128;
404 plt_entry_size = 32;
405 break;
406
407 default:
408 plt_header_size = shdr_plt.sh_entsize;
409 plt_entry_size = shdr_plt.sh_entsize;
410 break;
411 }
412 plt_offset += plt_header_size;
413
414 if (shdr_rel_plt.sh_type == SHT_RELA) {
415 GElf_Rela pos_mem, *pos;
416
417 elf_section__for_each_rela(reldata, pos, pos_mem, idx,
418 nr_rel_entries) {
419 const char *elf_name = NULL;
420 char *demangled = NULL;
421 symidx = GELF_R_SYM(pos->r_info);
422 gelf_getsym(syms, symidx, &sym);
423
424 elf_name = elf_sym__name(&sym, symstrs);
425 demangled = demangle_sym(dso, 0, elf_name);
426 if (demangled != NULL)
427 elf_name = demangled;
428 snprintf(sympltname, sizeof(sympltname),
429 "%s@plt", elf_name);
430 free(demangled);
431
432 f = symbol__new(plt_offset, plt_entry_size,
433 STB_GLOBAL, STT_FUNC, sympltname);
434 if (!f)
435 goto out_elf_end;
436
437 plt_offset += plt_entry_size;
438 symbols__insert(&dso->symbols, f);
439 ++nr;
440 }
441 } else if (shdr_rel_plt.sh_type == SHT_REL) {
442 GElf_Rel pos_mem, *pos;
443 elf_section__for_each_rel(reldata, pos, pos_mem, idx,
444 nr_rel_entries) {
445 const char *elf_name = NULL;
446 char *demangled = NULL;
447 symidx = GELF_R_SYM(pos->r_info);
448 gelf_getsym(syms, symidx, &sym);
449
450 elf_name = elf_sym__name(&sym, symstrs);
451 demangled = demangle_sym(dso, 0, elf_name);
452 if (demangled != NULL)
453 elf_name = demangled;
454 snprintf(sympltname, sizeof(sympltname),
455 "%s@plt", elf_name);
456 free(demangled);
457
458 f = symbol__new(plt_offset, plt_entry_size,
459 STB_GLOBAL, STT_FUNC, sympltname);
460 if (!f)
461 goto out_elf_end;
462
463 plt_offset += plt_entry_size;
464 symbols__insert(&dso->symbols, f);
465 ++nr;
466 }
467 }
468
469 err = 0;
470out_elf_end:
471 if (err == 0)
472 return nr;
473 pr_debug("%s: problems reading %s PLT info.\n",
474 __func__, dso->long_name);
475 return 0;
476}
477
478char *dso__demangle_sym(struct dso *dso, int kmodule, const char *elf_name)
479{
480 return demangle_sym(dso, kmodule, elf_name);
481}
482
483
484
485
486#define NOTE_ALIGN(n) (((n) + 3) & -4U)
487
488static int elf_read_build_id(Elf *elf, void *bf, size_t size)
489{
490 int err = -1;
491 GElf_Ehdr ehdr;
492 GElf_Shdr shdr;
493 Elf_Data *data;
494 Elf_Scn *sec;
495 Elf_Kind ek;
496 void *ptr;
497
498 if (size < BUILD_ID_SIZE)
499 goto out;
500
501 ek = elf_kind(elf);
502 if (ek != ELF_K_ELF)
503 goto out;
504
505 if (gelf_getehdr(elf, &ehdr) == NULL) {
506 pr_err("%s: cannot get elf header.\n", __func__);
507 goto out;
508 }
509
510
511
512
513
514
515
516 do {
517 sec = elf_section_by_name(elf, &ehdr, &shdr,
518 ".note.gnu.build-id", NULL);
519 if (sec)
520 break;
521
522 sec = elf_section_by_name(elf, &ehdr, &shdr,
523 ".notes", NULL);
524 if (sec)
525 break;
526
527 sec = elf_section_by_name(elf, &ehdr, &shdr,
528 ".note", NULL);
529 if (sec)
530 break;
531
532 return err;
533
534 } while (0);
535
536 data = elf_getdata(sec, NULL);
537 if (data == NULL)
538 goto out;
539
540 ptr = data->d_buf;
541 while (ptr < (data->d_buf + data->d_size)) {
542 GElf_Nhdr *nhdr = ptr;
543 size_t namesz = NOTE_ALIGN(nhdr->n_namesz),
544 descsz = NOTE_ALIGN(nhdr->n_descsz);
545 const char *name;
546
547 ptr += sizeof(*nhdr);
548 name = ptr;
549 ptr += namesz;
550 if (nhdr->n_type == NT_GNU_BUILD_ID &&
551 nhdr->n_namesz == sizeof("GNU")) {
552 if (memcmp(name, "GNU", sizeof("GNU")) == 0) {
553 size_t sz = min(size, descsz);
554 memcpy(bf, ptr, sz);
555 memset(bf + sz, 0, size - sz);
556 err = descsz;
557 break;
558 }
559 }
560 ptr += descsz;
561 }
562
563out:
564 return err;
565}
566
567#ifdef HAVE_LIBBFD_BUILDID_SUPPORT
568
569static int read_build_id(const char *filename, struct build_id *bid)
570{
571 size_t size = sizeof(bid->data);
572 int err = -1;
573 bfd *abfd;
574
575 abfd = bfd_openr(filename, NULL);
576 if (!abfd)
577 return -1;
578
579 if (!bfd_check_format(abfd, bfd_object)) {
580 pr_debug2("%s: cannot read %s bfd file.\n", __func__, filename);
581 goto out_close;
582 }
583
584 if (!abfd->build_id || abfd->build_id->size > size)
585 goto out_close;
586
587 memcpy(bid->data, abfd->build_id->data, abfd->build_id->size);
588 memset(bid->data + abfd->build_id->size, 0, size - abfd->build_id->size);
589 err = bid->size = abfd->build_id->size;
590
591out_close:
592 bfd_close(abfd);
593 return err;
594}
595
596#else
597
598static int read_build_id(const char *filename, struct build_id *bid)
599{
600 size_t size = sizeof(bid->data);
601 int fd, err = -1;
602 Elf *elf;
603
604 if (size < BUILD_ID_SIZE)
605 goto out;
606
607 fd = open(filename, O_RDONLY);
608 if (fd < 0)
609 goto out;
610
611 elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
612 if (elf == NULL) {
613 pr_debug2("%s: cannot read %s ELF file.\n", __func__, filename);
614 goto out_close;
615 }
616
617 err = elf_read_build_id(elf, bid->data, size);
618 if (err > 0)
619 bid->size = err;
620
621 elf_end(elf);
622out_close:
623 close(fd);
624out:
625 return err;
626}
627
628#endif
629
630int filename__read_build_id(const char *filename, struct build_id *bid)
631{
632 struct kmod_path m = { .name = NULL, };
633 char path[PATH_MAX];
634 int err;
635
636 if (!filename)
637 return -EFAULT;
638
639 err = kmod_path__parse(&m, filename);
640 if (err)
641 return -1;
642
643 if (m.comp) {
644 int error = 0, fd;
645
646 fd = filename__decompress(filename, path, sizeof(path), m.comp, &error);
647 if (fd < 0) {
648 pr_debug("Failed to decompress (error %d) %s\n",
649 error, filename);
650 return -1;
651 }
652 close(fd);
653 filename = path;
654 }
655
656 err = read_build_id(filename, bid);
657
658 if (m.comp)
659 unlink(filename);
660 return err;
661}
662
663int sysfs__read_build_id(const char *filename, struct build_id *bid)
664{
665 size_t size = sizeof(bid->data);
666 int fd, err = -1;
667
668 fd = open(filename, O_RDONLY);
669 if (fd < 0)
670 goto out;
671
672 while (1) {
673 char bf[BUFSIZ];
674 GElf_Nhdr nhdr;
675 size_t namesz, descsz;
676
677 if (read(fd, &nhdr, sizeof(nhdr)) != sizeof(nhdr))
678 break;
679
680 namesz = NOTE_ALIGN(nhdr.n_namesz);
681 descsz = NOTE_ALIGN(nhdr.n_descsz);
682 if (nhdr.n_type == NT_GNU_BUILD_ID &&
683 nhdr.n_namesz == sizeof("GNU")) {
684 if (read(fd, bf, namesz) != (ssize_t)namesz)
685 break;
686 if (memcmp(bf, "GNU", sizeof("GNU")) == 0) {
687 size_t sz = min(descsz, size);
688 if (read(fd, bid->data, sz) == (ssize_t)sz) {
689 memset(bid->data + sz, 0, size - sz);
690 bid->size = sz;
691 err = 0;
692 break;
693 }
694 } else if (read(fd, bf, descsz) != (ssize_t)descsz)
695 break;
696 } else {
697 int n = namesz + descsz;
698
699 if (n > (int)sizeof(bf)) {
700 n = sizeof(bf);
701 pr_debug("%s: truncating reading of build id in sysfs file %s: n_namesz=%u, n_descsz=%u.\n",
702 __func__, filename, nhdr.n_namesz, nhdr.n_descsz);
703 }
704 if (read(fd, bf, n) != n)
705 break;
706 }
707 }
708 close(fd);
709out:
710 return err;
711}
712
713#ifdef HAVE_LIBBFD_SUPPORT
714
715int filename__read_debuglink(const char *filename, char *debuglink,
716 size_t size)
717{
718 int err = -1;
719 asection *section;
720 bfd *abfd;
721
722 abfd = bfd_openr(filename, NULL);
723 if (!abfd)
724 return -1;
725
726 if (!bfd_check_format(abfd, bfd_object)) {
727 pr_debug2("%s: cannot read %s bfd file.\n", __func__, filename);
728 goto out_close;
729 }
730
731 section = bfd_get_section_by_name(abfd, ".gnu_debuglink");
732 if (!section)
733 goto out_close;
734
735 if (section->size > size)
736 goto out_close;
737
738 if (!bfd_get_section_contents(abfd, section, debuglink, 0,
739 section->size))
740 goto out_close;
741
742 err = 0;
743
744out_close:
745 bfd_close(abfd);
746 return err;
747}
748
749#else
750
751int filename__read_debuglink(const char *filename, char *debuglink,
752 size_t size)
753{
754 int fd, err = -1;
755 Elf *elf;
756 GElf_Ehdr ehdr;
757 GElf_Shdr shdr;
758 Elf_Data *data;
759 Elf_Scn *sec;
760 Elf_Kind ek;
761
762 fd = open(filename, O_RDONLY);
763 if (fd < 0)
764 goto out;
765
766 elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
767 if (elf == NULL) {
768 pr_debug2("%s: cannot read %s ELF file.\n", __func__, filename);
769 goto out_close;
770 }
771
772 ek = elf_kind(elf);
773 if (ek != ELF_K_ELF)
774 goto out_elf_end;
775
776 if (gelf_getehdr(elf, &ehdr) == NULL) {
777 pr_err("%s: cannot get elf header.\n", __func__);
778 goto out_elf_end;
779 }
780
781 sec = elf_section_by_name(elf, &ehdr, &shdr,
782 ".gnu_debuglink", NULL);
783 if (sec == NULL)
784 goto out_elf_end;
785
786 data = elf_getdata(sec, NULL);
787 if (data == NULL)
788 goto out_elf_end;
789
790
791 strncpy(debuglink, data->d_buf, size);
792
793 err = 0;
794
795out_elf_end:
796 elf_end(elf);
797out_close:
798 close(fd);
799out:
800 return err;
801}
802
803#endif
804
805static int dso__swap_init(struct dso *dso, unsigned char eidata)
806{
807 static unsigned int const endian = 1;
808
809 dso->needs_swap = DSO_SWAP__NO;
810
811 switch (eidata) {
812 case ELFDATA2LSB:
813
814 if (*(unsigned char const *)&endian != 1)
815 dso->needs_swap = DSO_SWAP__YES;
816 break;
817
818 case ELFDATA2MSB:
819
820 if (*(unsigned char const *)&endian != 0)
821 dso->needs_swap = DSO_SWAP__YES;
822 break;
823
824 default:
825 pr_err("unrecognized DSO data encoding %d\n", eidata);
826 return -EINVAL;
827 }
828
829 return 0;
830}
831
832bool symsrc__possibly_runtime(struct symsrc *ss)
833{
834 return ss->dynsym || ss->opdsec;
835}
836
837bool symsrc__has_symtab(struct symsrc *ss)
838{
839 return ss->symtab != NULL;
840}
841
842void symsrc__destroy(struct symsrc *ss)
843{
844 zfree(&ss->name);
845 elf_end(ss->elf);
846 close(ss->fd);
847}
848
849bool elf__needs_adjust_symbols(GElf_Ehdr ehdr)
850{
851
852
853
854
855
856 return ehdr.e_type == ET_EXEC || ehdr.e_type == ET_REL ||
857 ehdr.e_type == ET_DYN;
858}
859
860int symsrc__init(struct symsrc *ss, struct dso *dso, const char *name,
861 enum dso_binary_type type)
862{
863 GElf_Ehdr ehdr;
864 Elf *elf;
865 int fd;
866
867 if (dso__needs_decompress(dso)) {
868 fd = dso__decompress_kmodule_fd(dso, name);
869 if (fd < 0)
870 return -1;
871
872 type = dso->symtab_type;
873 } else {
874 fd = open(name, O_RDONLY);
875 if (fd < 0) {
876 dso->load_errno = errno;
877 return -1;
878 }
879 }
880
881 elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
882 if (elf == NULL) {
883 pr_debug("%s: cannot read %s ELF file.\n", __func__, name);
884 dso->load_errno = DSO_LOAD_ERRNO__INVALID_ELF;
885 goto out_close;
886 }
887
888 if (gelf_getehdr(elf, &ehdr) == NULL) {
889 dso->load_errno = DSO_LOAD_ERRNO__INVALID_ELF;
890 pr_debug("%s: cannot get elf header.\n", __func__);
891 goto out_elf_end;
892 }
893
894 if (dso__swap_init(dso, ehdr.e_ident[EI_DATA])) {
895 dso->load_errno = DSO_LOAD_ERRNO__INTERNAL_ERROR;
896 goto out_elf_end;
897 }
898
899
900 if (dso->has_build_id && !symbol_conf.ignore_vmlinux_buildid) {
901 u8 build_id[BUILD_ID_SIZE];
902 struct build_id bid;
903 int size;
904
905 size = elf_read_build_id(elf, build_id, BUILD_ID_SIZE);
906 if (size <= 0) {
907 dso->load_errno = DSO_LOAD_ERRNO__CANNOT_READ_BUILDID;
908 goto out_elf_end;
909 }
910
911 build_id__init(&bid, build_id, size);
912 if (!dso__build_id_equal(dso, &bid)) {
913 pr_debug("%s: build id mismatch for %s.\n", __func__, name);
914 dso->load_errno = DSO_LOAD_ERRNO__MISMATCHING_BUILDID;
915 goto out_elf_end;
916 }
917 }
918
919 ss->is_64_bit = (gelf_getclass(elf) == ELFCLASS64);
920
921 ss->symtab = elf_section_by_name(elf, &ehdr, &ss->symshdr, ".symtab",
922 NULL);
923 if (ss->symshdr.sh_type != SHT_SYMTAB)
924 ss->symtab = NULL;
925
926 ss->dynsym_idx = 0;
927 ss->dynsym = elf_section_by_name(elf, &ehdr, &ss->dynshdr, ".dynsym",
928 &ss->dynsym_idx);
929 if (ss->dynshdr.sh_type != SHT_DYNSYM)
930 ss->dynsym = NULL;
931
932 ss->opdidx = 0;
933 ss->opdsec = elf_section_by_name(elf, &ehdr, &ss->opdshdr, ".opd",
934 &ss->opdidx);
935 if (ss->opdshdr.sh_type != SHT_PROGBITS)
936 ss->opdsec = NULL;
937
938 if (dso->kernel == DSO_SPACE__USER)
939 ss->adjust_symbols = true;
940 else
941 ss->adjust_symbols = elf__needs_adjust_symbols(ehdr);
942
943 ss->name = strdup(name);
944 if (!ss->name) {
945 dso->load_errno = errno;
946 goto out_elf_end;
947 }
948
949 ss->elf = elf;
950 ss->fd = fd;
951 ss->ehdr = ehdr;
952 ss->type = type;
953
954 return 0;
955
956out_elf_end:
957 elf_end(elf);
958out_close:
959 close(fd);
960 return -1;
961}
962
963
964
965
966
967
968
969
970
971static bool ref_reloc_sym_not_found(struct kmap *kmap)
972{
973 return kmap && kmap->ref_reloc_sym && kmap->ref_reloc_sym->name &&
974 !kmap->ref_reloc_sym->unrelocated_addr;
975}
976
977
978
979
980
981
982
983
984
985static u64 ref_reloc(struct kmap *kmap)
986{
987 if (kmap && kmap->ref_reloc_sym &&
988 kmap->ref_reloc_sym->unrelocated_addr)
989 return kmap->ref_reloc_sym->addr -
990 kmap->ref_reloc_sym->unrelocated_addr;
991 return 0;
992}
993
994void __weak arch__sym_update(struct symbol *s __maybe_unused,
995 GElf_Sym *sym __maybe_unused) { }
996
997static int dso__process_kernel_symbol(struct dso *dso, struct map *map,
998 GElf_Sym *sym, GElf_Shdr *shdr,
999 struct maps *kmaps, struct kmap *kmap,
1000 struct dso **curr_dsop, struct map **curr_mapp,
1001 const char *section_name,
1002 bool adjust_kernel_syms, bool kmodule, bool *remap_kernel)
1003{
1004 struct dso *curr_dso = *curr_dsop;
1005 struct map *curr_map;
1006 char dso_name[PATH_MAX];
1007
1008
1009 if (adjust_kernel_syms)
1010 sym->st_value -= shdr->sh_addr - shdr->sh_offset;
1011
1012 if (strcmp(section_name, (curr_dso->short_name + dso->short_name_len)) == 0)
1013 return 0;
1014
1015 if (strcmp(section_name, ".text") == 0) {
1016
1017
1018
1019
1020
1021 if (*remap_kernel && dso->kernel && !kmodule) {
1022 *remap_kernel = false;
1023 map->start = shdr->sh_addr + ref_reloc(kmap);
1024 map->end = map->start + shdr->sh_size;
1025 map->pgoff = shdr->sh_offset;
1026 map->map_ip = map__map_ip;
1027 map->unmap_ip = map__unmap_ip;
1028
1029 if (kmaps) {
1030 map__get(map);
1031 maps__remove(kmaps, map);
1032 maps__insert(kmaps, map);
1033 map__put(map);
1034 }
1035 }
1036
1037
1038
1039
1040
1041
1042 if (*remap_kernel && kmodule) {
1043 *remap_kernel = false;
1044 map->pgoff = shdr->sh_offset;
1045 }
1046
1047 *curr_mapp = map;
1048 *curr_dsop = dso;
1049 return 0;
1050 }
1051
1052 if (!kmap)
1053 return 0;
1054
1055 snprintf(dso_name, sizeof(dso_name), "%s%s", dso->short_name, section_name);
1056
1057 curr_map = maps__find_by_name(kmaps, dso_name);
1058 if (curr_map == NULL) {
1059 u64 start = sym->st_value;
1060
1061 if (kmodule)
1062 start += map->start + shdr->sh_offset;
1063
1064 curr_dso = dso__new(dso_name);
1065 if (curr_dso == NULL)
1066 return -1;
1067 curr_dso->kernel = dso->kernel;
1068 curr_dso->long_name = dso->long_name;
1069 curr_dso->long_name_len = dso->long_name_len;
1070 curr_map = map__new2(start, curr_dso);
1071 dso__put(curr_dso);
1072 if (curr_map == NULL)
1073 return -1;
1074
1075 if (curr_dso->kernel)
1076 map__kmap(curr_map)->kmaps = kmaps;
1077
1078 if (adjust_kernel_syms) {
1079 curr_map->start = shdr->sh_addr + ref_reloc(kmap);
1080 curr_map->end = curr_map->start + shdr->sh_size;
1081 curr_map->pgoff = shdr->sh_offset;
1082 } else {
1083 curr_map->map_ip = curr_map->unmap_ip = identity__map_ip;
1084 }
1085 curr_dso->symtab_type = dso->symtab_type;
1086 maps__insert(kmaps, curr_map);
1087
1088
1089
1090
1091
1092 dsos__add(&kmaps->machine->dsos, curr_dso);
1093
1094 map__put(curr_map);
1095 dso__set_loaded(curr_dso);
1096 *curr_mapp = curr_map;
1097 *curr_dsop = curr_dso;
1098 } else
1099 *curr_dsop = curr_map->dso;
1100
1101 return 0;
1102}
1103
1104static int
1105dso__load_sym_internal(struct dso *dso, struct map *map, struct symsrc *syms_ss,
1106 struct symsrc *runtime_ss, int kmodule, int dynsym)
1107{
1108 struct kmap *kmap = dso->kernel ? map__kmap(map) : NULL;
1109 struct maps *kmaps = kmap ? map__kmaps(map) : NULL;
1110 struct map *curr_map = map;
1111 struct dso *curr_dso = dso;
1112 Elf_Data *symstrs, *secstrs, *secstrs_run, *secstrs_sym;
1113 uint32_t nr_syms;
1114 int err = -1;
1115 uint32_t idx;
1116 GElf_Ehdr ehdr;
1117 GElf_Shdr shdr;
1118 GElf_Shdr tshdr;
1119 Elf_Data *syms, *opddata = NULL;
1120 GElf_Sym sym;
1121 Elf_Scn *sec, *sec_strndx;
1122 Elf *elf;
1123 int nr = 0;
1124 bool remap_kernel = false, adjust_kernel_syms = false;
1125
1126 if (kmap && !kmaps)
1127 return -1;
1128
1129 elf = syms_ss->elf;
1130 ehdr = syms_ss->ehdr;
1131 if (dynsym) {
1132 sec = syms_ss->dynsym;
1133 shdr = syms_ss->dynshdr;
1134 } else {
1135 sec = syms_ss->symtab;
1136 shdr = syms_ss->symshdr;
1137 }
1138
1139 if (elf_section_by_name(runtime_ss->elf, &runtime_ss->ehdr, &tshdr,
1140 ".text", NULL))
1141 dso->text_offset = tshdr.sh_addr - tshdr.sh_offset;
1142
1143 if (runtime_ss->opdsec)
1144 opddata = elf_rawdata(runtime_ss->opdsec, NULL);
1145
1146 syms = elf_getdata(sec, NULL);
1147 if (syms == NULL)
1148 goto out_elf_end;
1149
1150 sec = elf_getscn(elf, shdr.sh_link);
1151 if (sec == NULL)
1152 goto out_elf_end;
1153
1154 symstrs = elf_getdata(sec, NULL);
1155 if (symstrs == NULL)
1156 goto out_elf_end;
1157
1158 sec_strndx = elf_getscn(runtime_ss->elf, runtime_ss->ehdr.e_shstrndx);
1159 if (sec_strndx == NULL)
1160 goto out_elf_end;
1161
1162 secstrs_run = elf_getdata(sec_strndx, NULL);
1163 if (secstrs_run == NULL)
1164 goto out_elf_end;
1165
1166 sec_strndx = elf_getscn(elf, ehdr.e_shstrndx);
1167 if (sec_strndx == NULL)
1168 goto out_elf_end;
1169
1170 secstrs_sym = elf_getdata(sec_strndx, NULL);
1171 if (secstrs_sym == NULL)
1172 goto out_elf_end;
1173
1174 nr_syms = shdr.sh_size / shdr.sh_entsize;
1175
1176 memset(&sym, 0, sizeof(sym));
1177
1178
1179
1180
1181
1182 if (ref_reloc_sym_not_found(kmap)) {
1183 elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) {
1184 const char *elf_name = elf_sym__name(&sym, symstrs);
1185
1186 if (strcmp(elf_name, kmap->ref_reloc_sym->name))
1187 continue;
1188 kmap->ref_reloc_sym->unrelocated_addr = sym.st_value;
1189 map->reloc = kmap->ref_reloc_sym->addr -
1190 kmap->ref_reloc_sym->unrelocated_addr;
1191 break;
1192 }
1193 }
1194
1195
1196
1197
1198
1199 if (dso__is_vdso(dso))
1200 map->reloc = map->start - dso->text_offset;
1201
1202 dso->adjust_symbols = runtime_ss->adjust_symbols || ref_reloc(kmap);
1203
1204
1205
1206
1207 if (dso->kernel) {
1208 remap_kernel = true;
1209 adjust_kernel_syms = dso->adjust_symbols;
1210 }
1211 elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) {
1212 struct symbol *f;
1213 const char *elf_name = elf_sym__name(&sym, symstrs);
1214 char *demangled = NULL;
1215 int is_label = elf_sym__is_label(&sym);
1216 const char *section_name;
1217 bool used_opd = false;
1218
1219 if (!is_label && !elf_sym__filter(&sym))
1220 continue;
1221
1222
1223
1224
1225 if (ehdr.e_machine == EM_ARM || ehdr.e_machine == EM_AARCH64) {
1226 if (elf_name[0] == '$' && strchr("adtx", elf_name[1])
1227 && (elf_name[2] == '\0' || elf_name[2] == '.'))
1228 continue;
1229 }
1230
1231 if (runtime_ss->opdsec && sym.st_shndx == runtime_ss->opdidx) {
1232 u32 offset = sym.st_value - syms_ss->opdshdr.sh_addr;
1233 u64 *opd = opddata->d_buf + offset;
1234 sym.st_value = DSO__SWAP(dso, u64, *opd);
1235 sym.st_shndx = elf_addr_to_index(runtime_ss->elf,
1236 sym.st_value);
1237 used_opd = true;
1238 }
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249 if (sym.st_shndx == SHN_ABS)
1250 continue;
1251
1252 sec = elf_getscn(syms_ss->elf, sym.st_shndx);
1253 if (!sec)
1254 goto out_elf_end;
1255
1256 gelf_getshdr(sec, &shdr);
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266 if (!(shdr.sh_flags & SHF_ALLOC))
1267 continue;
1268
1269 secstrs = secstrs_sym;
1270
1271
1272
1273
1274
1275
1276
1277 if (shdr.sh_type == SHT_NOBITS) {
1278 sec = elf_getscn(runtime_ss->elf, sym.st_shndx);
1279 if (!sec)
1280 goto out_elf_end;
1281
1282 gelf_getshdr(sec, &shdr);
1283 secstrs = secstrs_run;
1284 }
1285
1286 if (is_label && !elf_sec__filter(&shdr, secstrs))
1287 continue;
1288
1289 section_name = elf_sec__name(&shdr, secstrs);
1290
1291
1292
1293 if ((ehdr.e_machine == EM_ARM) &&
1294 (GELF_ST_TYPE(sym.st_info) == STT_FUNC) &&
1295 (sym.st_value & 1))
1296 --sym.st_value;
1297
1298 if (dso->kernel) {
1299 if (dso__process_kernel_symbol(dso, map, &sym, &shdr, kmaps, kmap, &curr_dso, &curr_map,
1300 section_name, adjust_kernel_syms, kmodule, &remap_kernel))
1301 goto out_elf_end;
1302 } else if ((used_opd && runtime_ss->adjust_symbols) ||
1303 (!used_opd && syms_ss->adjust_symbols)) {
1304 GElf_Phdr phdr;
1305
1306 if (elf_read_program_header(syms_ss->elf,
1307 (u64)sym.st_value, &phdr)) {
1308 pr_warning("%s: failed to find program header for "
1309 "symbol: %s st_value: %#" PRIx64 "\n",
1310 __func__, elf_name, (u64)sym.st_value);
1311 continue;
1312 }
1313 pr_debug4("%s: adjusting symbol: st_value: %#" PRIx64 " "
1314 "p_vaddr: %#" PRIx64 " p_offset: %#" PRIx64 "\n",
1315 __func__, (u64)sym.st_value, (u64)phdr.p_vaddr,
1316 (u64)phdr.p_offset);
1317 sym.st_value -= phdr.p_vaddr - phdr.p_offset;
1318 }
1319
1320 demangled = demangle_sym(dso, kmodule, elf_name);
1321 if (demangled != NULL)
1322 elf_name = demangled;
1323
1324 f = symbol__new(sym.st_value, sym.st_size,
1325 GELF_ST_BIND(sym.st_info),
1326 GELF_ST_TYPE(sym.st_info), elf_name);
1327 free(demangled);
1328 if (!f)
1329 goto out_elf_end;
1330
1331 arch__sym_update(f, &sym);
1332
1333 __symbols__insert(&curr_dso->symbols, f, dso->kernel);
1334 nr++;
1335 }
1336
1337
1338
1339
1340 if (nr > 0) {
1341 symbols__fixup_end(&dso->symbols, false);
1342 symbols__fixup_duplicate(&dso->symbols);
1343 if (kmap) {
1344
1345
1346
1347
1348 maps__fixup_end(kmaps);
1349 }
1350 }
1351 err = nr;
1352out_elf_end:
1353 return err;
1354}
1355
1356int dso__load_sym(struct dso *dso, struct map *map, struct symsrc *syms_ss,
1357 struct symsrc *runtime_ss, int kmodule)
1358{
1359 int nr = 0;
1360 int err = -1;
1361
1362 dso->symtab_type = syms_ss->type;
1363 dso->is_64_bit = syms_ss->is_64_bit;
1364 dso->rel = syms_ss->ehdr.e_type == ET_REL;
1365
1366
1367
1368
1369
1370 if (kmodule && syms_ss->symtab)
1371 symbols__delete(&dso->symbols);
1372
1373 if (!syms_ss->symtab) {
1374
1375
1376
1377
1378
1379 if (dso->kernel)
1380 return err;
1381 } else {
1382 err = dso__load_sym_internal(dso, map, syms_ss, runtime_ss,
1383 kmodule, 0);
1384 if (err < 0)
1385 return err;
1386 nr = err;
1387 }
1388
1389 if (syms_ss->dynsym) {
1390 err = dso__load_sym_internal(dso, map, syms_ss, runtime_ss,
1391 kmodule, 1);
1392 if (err < 0)
1393 return err;
1394 err += nr;
1395 }
1396
1397 return err;
1398}
1399
1400static int elf_read_maps(Elf *elf, bool exe, mapfn_t mapfn, void *data)
1401{
1402 GElf_Phdr phdr;
1403 size_t i, phdrnum;
1404 int err;
1405 u64 sz;
1406
1407 if (elf_getphdrnum(elf, &phdrnum))
1408 return -1;
1409
1410 for (i = 0; i < phdrnum; i++) {
1411 if (gelf_getphdr(elf, i, &phdr) == NULL)
1412 return -1;
1413 if (phdr.p_type != PT_LOAD)
1414 continue;
1415 if (exe) {
1416 if (!(phdr.p_flags & PF_X))
1417 continue;
1418 } else {
1419 if (!(phdr.p_flags & PF_R))
1420 continue;
1421 }
1422 sz = min(phdr.p_memsz, phdr.p_filesz);
1423 if (!sz)
1424 continue;
1425 err = mapfn(phdr.p_vaddr, sz, phdr.p_offset, data);
1426 if (err)
1427 return err;
1428 }
1429 return 0;
1430}
1431
1432int file__read_maps(int fd, bool exe, mapfn_t mapfn, void *data,
1433 bool *is_64_bit)
1434{
1435 int err;
1436 Elf *elf;
1437
1438 elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
1439 if (elf == NULL)
1440 return -1;
1441
1442 if (is_64_bit)
1443 *is_64_bit = (gelf_getclass(elf) == ELFCLASS64);
1444
1445 err = elf_read_maps(elf, exe, mapfn, data);
1446
1447 elf_end(elf);
1448 return err;
1449}
1450
1451enum dso_type dso__type_fd(int fd)
1452{
1453 enum dso_type dso_type = DSO__TYPE_UNKNOWN;
1454 GElf_Ehdr ehdr;
1455 Elf_Kind ek;
1456 Elf *elf;
1457
1458 elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
1459 if (elf == NULL)
1460 goto out;
1461
1462 ek = elf_kind(elf);
1463 if (ek != ELF_K_ELF)
1464 goto out_end;
1465
1466 if (gelf_getclass(elf) == ELFCLASS64) {
1467 dso_type = DSO__TYPE_64BIT;
1468 goto out_end;
1469 }
1470
1471 if (gelf_getehdr(elf, &ehdr) == NULL)
1472 goto out_end;
1473
1474 if (ehdr.e_machine == EM_X86_64)
1475 dso_type = DSO__TYPE_X32BIT;
1476 else
1477 dso_type = DSO__TYPE_32BIT;
1478out_end:
1479 elf_end(elf);
1480out:
1481 return dso_type;
1482}
1483
1484static int copy_bytes(int from, off_t from_offs, int to, off_t to_offs, u64 len)
1485{
1486 ssize_t r;
1487 size_t n;
1488 int err = -1;
1489 char *buf = malloc(page_size);
1490
1491 if (buf == NULL)
1492 return -1;
1493
1494 if (lseek(to, to_offs, SEEK_SET) != to_offs)
1495 goto out;
1496
1497 if (lseek(from, from_offs, SEEK_SET) != from_offs)
1498 goto out;
1499
1500 while (len) {
1501 n = page_size;
1502 if (len < n)
1503 n = len;
1504
1505 r = read(from, buf, n);
1506 if (r < 0)
1507 goto out;
1508 if (!r)
1509 break;
1510 n = r;
1511 r = write(to, buf, n);
1512 if (r < 0)
1513 goto out;
1514 if ((size_t)r != n)
1515 goto out;
1516 len -= n;
1517 }
1518
1519 err = 0;
1520out:
1521 free(buf);
1522 return err;
1523}
1524
1525struct kcore {
1526 int fd;
1527 int elfclass;
1528 Elf *elf;
1529 GElf_Ehdr ehdr;
1530};
1531
1532static int kcore__open(struct kcore *kcore, const char *filename)
1533{
1534 GElf_Ehdr *ehdr;
1535
1536 kcore->fd = open(filename, O_RDONLY);
1537 if (kcore->fd == -1)
1538 return -1;
1539
1540 kcore->elf = elf_begin(kcore->fd, ELF_C_READ, NULL);
1541 if (!kcore->elf)
1542 goto out_close;
1543
1544 kcore->elfclass = gelf_getclass(kcore->elf);
1545 if (kcore->elfclass == ELFCLASSNONE)
1546 goto out_end;
1547
1548 ehdr = gelf_getehdr(kcore->elf, &kcore->ehdr);
1549 if (!ehdr)
1550 goto out_end;
1551
1552 return 0;
1553
1554out_end:
1555 elf_end(kcore->elf);
1556out_close:
1557 close(kcore->fd);
1558 return -1;
1559}
1560
1561static int kcore__init(struct kcore *kcore, char *filename, int elfclass,
1562 bool temp)
1563{
1564 kcore->elfclass = elfclass;
1565
1566 if (temp)
1567 kcore->fd = mkstemp(filename);
1568 else
1569 kcore->fd = open(filename, O_WRONLY | O_CREAT | O_EXCL, 0400);
1570 if (kcore->fd == -1)
1571 return -1;
1572
1573 kcore->elf = elf_begin(kcore->fd, ELF_C_WRITE, NULL);
1574 if (!kcore->elf)
1575 goto out_close;
1576
1577 if (!gelf_newehdr(kcore->elf, elfclass))
1578 goto out_end;
1579
1580 memset(&kcore->ehdr, 0, sizeof(GElf_Ehdr));
1581
1582 return 0;
1583
1584out_end:
1585 elf_end(kcore->elf);
1586out_close:
1587 close(kcore->fd);
1588 unlink(filename);
1589 return -1;
1590}
1591
1592static void kcore__close(struct kcore *kcore)
1593{
1594 elf_end(kcore->elf);
1595 close(kcore->fd);
1596}
1597
1598static int kcore__copy_hdr(struct kcore *from, struct kcore *to, size_t count)
1599{
1600 GElf_Ehdr *ehdr = &to->ehdr;
1601 GElf_Ehdr *kehdr = &from->ehdr;
1602
1603 memcpy(ehdr->e_ident, kehdr->e_ident, EI_NIDENT);
1604 ehdr->e_type = kehdr->e_type;
1605 ehdr->e_machine = kehdr->e_machine;
1606 ehdr->e_version = kehdr->e_version;
1607 ehdr->e_entry = 0;
1608 ehdr->e_shoff = 0;
1609 ehdr->e_flags = kehdr->e_flags;
1610 ehdr->e_phnum = count;
1611 ehdr->e_shentsize = 0;
1612 ehdr->e_shnum = 0;
1613 ehdr->e_shstrndx = 0;
1614
1615 if (from->elfclass == ELFCLASS32) {
1616 ehdr->e_phoff = sizeof(Elf32_Ehdr);
1617 ehdr->e_ehsize = sizeof(Elf32_Ehdr);
1618 ehdr->e_phentsize = sizeof(Elf32_Phdr);
1619 } else {
1620 ehdr->e_phoff = sizeof(Elf64_Ehdr);
1621 ehdr->e_ehsize = sizeof(Elf64_Ehdr);
1622 ehdr->e_phentsize = sizeof(Elf64_Phdr);
1623 }
1624
1625 if (!gelf_update_ehdr(to->elf, ehdr))
1626 return -1;
1627
1628 if (!gelf_newphdr(to->elf, count))
1629 return -1;
1630
1631 return 0;
1632}
1633
1634static int kcore__add_phdr(struct kcore *kcore, int idx, off_t offset,
1635 u64 addr, u64 len)
1636{
1637 GElf_Phdr phdr = {
1638 .p_type = PT_LOAD,
1639 .p_flags = PF_R | PF_W | PF_X,
1640 .p_offset = offset,
1641 .p_vaddr = addr,
1642 .p_paddr = 0,
1643 .p_filesz = len,
1644 .p_memsz = len,
1645 .p_align = page_size,
1646 };
1647
1648 if (!gelf_update_phdr(kcore->elf, idx, &phdr))
1649 return -1;
1650
1651 return 0;
1652}
1653
1654static off_t kcore__write(struct kcore *kcore)
1655{
1656 return elf_update(kcore->elf, ELF_C_WRITE);
1657}
1658
1659struct phdr_data {
1660 off_t offset;
1661 off_t rel;
1662 u64 addr;
1663 u64 len;
1664 struct list_head node;
1665 struct phdr_data *remaps;
1666};
1667
1668struct sym_data {
1669 u64 addr;
1670 struct list_head node;
1671};
1672
1673struct kcore_copy_info {
1674 u64 stext;
1675 u64 etext;
1676 u64 first_symbol;
1677 u64 last_symbol;
1678 u64 first_module;
1679 u64 first_module_symbol;
1680 u64 last_module_symbol;
1681 size_t phnum;
1682 struct list_head phdrs;
1683 struct list_head syms;
1684};
1685
1686#define kcore_copy__for_each_phdr(k, p) \
1687 list_for_each_entry((p), &(k)->phdrs, node)
1688
1689static struct phdr_data *phdr_data__new(u64 addr, u64 len, off_t offset)
1690{
1691 struct phdr_data *p = zalloc(sizeof(*p));
1692
1693 if (p) {
1694 p->addr = addr;
1695 p->len = len;
1696 p->offset = offset;
1697 }
1698
1699 return p;
1700}
1701
1702static struct phdr_data *kcore_copy_info__addnew(struct kcore_copy_info *kci,
1703 u64 addr, u64 len,
1704 off_t offset)
1705{
1706 struct phdr_data *p = phdr_data__new(addr, len, offset);
1707
1708 if (p)
1709 list_add_tail(&p->node, &kci->phdrs);
1710
1711 return p;
1712}
1713
1714static void kcore_copy__free_phdrs(struct kcore_copy_info *kci)
1715{
1716 struct phdr_data *p, *tmp;
1717
1718 list_for_each_entry_safe(p, tmp, &kci->phdrs, node) {
1719 list_del_init(&p->node);
1720 free(p);
1721 }
1722}
1723
1724static struct sym_data *kcore_copy__new_sym(struct kcore_copy_info *kci,
1725 u64 addr)
1726{
1727 struct sym_data *s = zalloc(sizeof(*s));
1728
1729 if (s) {
1730 s->addr = addr;
1731 list_add_tail(&s->node, &kci->syms);
1732 }
1733
1734 return s;
1735}
1736
1737static void kcore_copy__free_syms(struct kcore_copy_info *kci)
1738{
1739 struct sym_data *s, *tmp;
1740
1741 list_for_each_entry_safe(s, tmp, &kci->syms, node) {
1742 list_del_init(&s->node);
1743 free(s);
1744 }
1745}
1746
1747static int kcore_copy__process_kallsyms(void *arg, const char *name, char type,
1748 u64 start)
1749{
1750 struct kcore_copy_info *kci = arg;
1751
1752 if (!kallsyms__is_function(type))
1753 return 0;
1754
1755 if (strchr(name, '[')) {
1756 if (!kci->first_module_symbol || start < kci->first_module_symbol)
1757 kci->first_module_symbol = start;
1758 if (start > kci->last_module_symbol)
1759 kci->last_module_symbol = start;
1760 return 0;
1761 }
1762
1763 if (!kci->first_symbol || start < kci->first_symbol)
1764 kci->first_symbol = start;
1765
1766 if (!kci->last_symbol || start > kci->last_symbol)
1767 kci->last_symbol = start;
1768
1769 if (!strcmp(name, "_stext")) {
1770 kci->stext = start;
1771 return 0;
1772 }
1773
1774 if (!strcmp(name, "_etext")) {
1775 kci->etext = start;
1776 return 0;
1777 }
1778
1779 if (is_entry_trampoline(name) && !kcore_copy__new_sym(kci, start))
1780 return -1;
1781
1782 return 0;
1783}
1784
1785static int kcore_copy__parse_kallsyms(struct kcore_copy_info *kci,
1786 const char *dir)
1787{
1788 char kallsyms_filename[PATH_MAX];
1789
1790 scnprintf(kallsyms_filename, PATH_MAX, "%s/kallsyms", dir);
1791
1792 if (symbol__restricted_filename(kallsyms_filename, "/proc/kallsyms"))
1793 return -1;
1794
1795 if (kallsyms__parse(kallsyms_filename, kci,
1796 kcore_copy__process_kallsyms) < 0)
1797 return -1;
1798
1799 return 0;
1800}
1801
1802static int kcore_copy__process_modules(void *arg,
1803 const char *name __maybe_unused,
1804 u64 start, u64 size __maybe_unused)
1805{
1806 struct kcore_copy_info *kci = arg;
1807
1808 if (!kci->first_module || start < kci->first_module)
1809 kci->first_module = start;
1810
1811 return 0;
1812}
1813
1814static int kcore_copy__parse_modules(struct kcore_copy_info *kci,
1815 const char *dir)
1816{
1817 char modules_filename[PATH_MAX];
1818
1819 scnprintf(modules_filename, PATH_MAX, "%s/modules", dir);
1820
1821 if (symbol__restricted_filename(modules_filename, "/proc/modules"))
1822 return -1;
1823
1824 if (modules__parse(modules_filename, kci,
1825 kcore_copy__process_modules) < 0)
1826 return -1;
1827
1828 return 0;
1829}
1830
1831static int kcore_copy__map(struct kcore_copy_info *kci, u64 start, u64 end,
1832 u64 pgoff, u64 s, u64 e)
1833{
1834 u64 len, offset;
1835
1836 if (s < start || s >= end)
1837 return 0;
1838
1839 offset = (s - start) + pgoff;
1840 len = e < end ? e - s : end - s;
1841
1842 return kcore_copy_info__addnew(kci, s, len, offset) ? 0 : -1;
1843}
1844
1845static int kcore_copy__read_map(u64 start, u64 len, u64 pgoff, void *data)
1846{
1847 struct kcore_copy_info *kci = data;
1848 u64 end = start + len;
1849 struct sym_data *sdat;
1850
1851 if (kcore_copy__map(kci, start, end, pgoff, kci->stext, kci->etext))
1852 return -1;
1853
1854 if (kcore_copy__map(kci, start, end, pgoff, kci->first_module,
1855 kci->last_module_symbol))
1856 return -1;
1857
1858 list_for_each_entry(sdat, &kci->syms, node) {
1859 u64 s = round_down(sdat->addr, page_size);
1860
1861 if (kcore_copy__map(kci, start, end, pgoff, s, s + len))
1862 return -1;
1863 }
1864
1865 return 0;
1866}
1867
1868static int kcore_copy__read_maps(struct kcore_copy_info *kci, Elf *elf)
1869{
1870 if (elf_read_maps(elf, true, kcore_copy__read_map, kci) < 0)
1871 return -1;
1872
1873 return 0;
1874}
1875
1876static void kcore_copy__find_remaps(struct kcore_copy_info *kci)
1877{
1878 struct phdr_data *p, *k = NULL;
1879 u64 kend;
1880
1881 if (!kci->stext)
1882 return;
1883
1884
1885 kcore_copy__for_each_phdr(kci, p) {
1886 u64 pend = p->addr + p->len - 1;
1887
1888 if (p->addr <= kci->stext && pend >= kci->stext) {
1889 k = p;
1890 break;
1891 }
1892 }
1893
1894 if (!k)
1895 return;
1896
1897 kend = k->offset + k->len;
1898
1899
1900 kcore_copy__for_each_phdr(kci, p) {
1901 u64 pend = p->offset + p->len;
1902
1903 if (p == k)
1904 continue;
1905
1906 if (p->offset >= k->offset && pend <= kend)
1907 p->remaps = k;
1908 }
1909}
1910
1911static void kcore_copy__layout(struct kcore_copy_info *kci)
1912{
1913 struct phdr_data *p;
1914 off_t rel = 0;
1915
1916 kcore_copy__find_remaps(kci);
1917
1918 kcore_copy__for_each_phdr(kci, p) {
1919 if (!p->remaps) {
1920 p->rel = rel;
1921 rel += p->len;
1922 }
1923 kci->phnum += 1;
1924 }
1925
1926 kcore_copy__for_each_phdr(kci, p) {
1927 struct phdr_data *k = p->remaps;
1928
1929 if (k)
1930 p->rel = p->offset - k->offset + k->rel;
1931 }
1932}
1933
1934static int kcore_copy__calc_maps(struct kcore_copy_info *kci, const char *dir,
1935 Elf *elf)
1936{
1937 if (kcore_copy__parse_kallsyms(kci, dir))
1938 return -1;
1939
1940 if (kcore_copy__parse_modules(kci, dir))
1941 return -1;
1942
1943 if (kci->stext)
1944 kci->stext = round_down(kci->stext, page_size);
1945 else
1946 kci->stext = round_down(kci->first_symbol, page_size);
1947
1948 if (kci->etext) {
1949 kci->etext = round_up(kci->etext, page_size);
1950 } else if (kci->last_symbol) {
1951 kci->etext = round_up(kci->last_symbol, page_size);
1952 kci->etext += page_size;
1953 }
1954
1955 if (kci->first_module_symbol &&
1956 (!kci->first_module || kci->first_module_symbol < kci->first_module))
1957 kci->first_module = kci->first_module_symbol;
1958
1959 kci->first_module = round_down(kci->first_module, page_size);
1960
1961 if (kci->last_module_symbol) {
1962 kci->last_module_symbol = round_up(kci->last_module_symbol,
1963 page_size);
1964 kci->last_module_symbol += page_size;
1965 }
1966
1967 if (!kci->stext || !kci->etext)
1968 return -1;
1969
1970 if (kci->first_module && !kci->last_module_symbol)
1971 return -1;
1972
1973 if (kcore_copy__read_maps(kci, elf))
1974 return -1;
1975
1976 kcore_copy__layout(kci);
1977
1978 return 0;
1979}
1980
1981static int kcore_copy__copy_file(const char *from_dir, const char *to_dir,
1982 const char *name)
1983{
1984 char from_filename[PATH_MAX];
1985 char to_filename[PATH_MAX];
1986
1987 scnprintf(from_filename, PATH_MAX, "%s/%s", from_dir, name);
1988 scnprintf(to_filename, PATH_MAX, "%s/%s", to_dir, name);
1989
1990 return copyfile_mode(from_filename, to_filename, 0400);
1991}
1992
1993static int kcore_copy__unlink(const char *dir, const char *name)
1994{
1995 char filename[PATH_MAX];
1996
1997 scnprintf(filename, PATH_MAX, "%s/%s", dir, name);
1998
1999 return unlink(filename);
2000}
2001
2002static int kcore_copy__compare_fds(int from, int to)
2003{
2004 char *buf_from;
2005 char *buf_to;
2006 ssize_t ret;
2007 size_t len;
2008 int err = -1;
2009
2010 buf_from = malloc(page_size);
2011 buf_to = malloc(page_size);
2012 if (!buf_from || !buf_to)
2013 goto out;
2014
2015 while (1) {
2016
2017 ret = read(from, buf_from, page_size);
2018 if (ret < 0)
2019 goto out;
2020
2021 if (!ret)
2022 break;
2023
2024 len = ret;
2025
2026 if (readn(to, buf_to, len) != (int)len)
2027 goto out;
2028
2029 if (memcmp(buf_from, buf_to, len))
2030 goto out;
2031 }
2032
2033 err = 0;
2034out:
2035 free(buf_to);
2036 free(buf_from);
2037 return err;
2038}
2039
2040static int kcore_copy__compare_files(const char *from_filename,
2041 const char *to_filename)
2042{
2043 int from, to, err = -1;
2044
2045 from = open(from_filename, O_RDONLY);
2046 if (from < 0)
2047 return -1;
2048
2049 to = open(to_filename, O_RDONLY);
2050 if (to < 0)
2051 goto out_close_from;
2052
2053 err = kcore_copy__compare_fds(from, to);
2054
2055 close(to);
2056out_close_from:
2057 close(from);
2058 return err;
2059}
2060
2061static int kcore_copy__compare_file(const char *from_dir, const char *to_dir,
2062 const char *name)
2063{
2064 char from_filename[PATH_MAX];
2065 char to_filename[PATH_MAX];
2066
2067 scnprintf(from_filename, PATH_MAX, "%s/%s", from_dir, name);
2068 scnprintf(to_filename, PATH_MAX, "%s/%s", to_dir, name);
2069
2070 return kcore_copy__compare_files(from_filename, to_filename);
2071}
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097int kcore_copy(const char *from_dir, const char *to_dir)
2098{
2099 struct kcore kcore;
2100 struct kcore extract;
2101 int idx = 0, err = -1;
2102 off_t offset, sz;
2103 struct kcore_copy_info kci = { .stext = 0, };
2104 char kcore_filename[PATH_MAX];
2105 char extract_filename[PATH_MAX];
2106 struct phdr_data *p;
2107
2108 INIT_LIST_HEAD(&kci.phdrs);
2109 INIT_LIST_HEAD(&kci.syms);
2110
2111 if (kcore_copy__copy_file(from_dir, to_dir, "kallsyms"))
2112 return -1;
2113
2114 if (kcore_copy__copy_file(from_dir, to_dir, "modules"))
2115 goto out_unlink_kallsyms;
2116
2117 scnprintf(kcore_filename, PATH_MAX, "%s/kcore", from_dir);
2118 scnprintf(extract_filename, PATH_MAX, "%s/kcore", to_dir);
2119
2120 if (kcore__open(&kcore, kcore_filename))
2121 goto out_unlink_modules;
2122
2123 if (kcore_copy__calc_maps(&kci, from_dir, kcore.elf))
2124 goto out_kcore_close;
2125
2126 if (kcore__init(&extract, extract_filename, kcore.elfclass, false))
2127 goto out_kcore_close;
2128
2129 if (kcore__copy_hdr(&kcore, &extract, kci.phnum))
2130 goto out_extract_close;
2131
2132 offset = gelf_fsize(extract.elf, ELF_T_EHDR, 1, EV_CURRENT) +
2133 gelf_fsize(extract.elf, ELF_T_PHDR, kci.phnum, EV_CURRENT);
2134 offset = round_up(offset, page_size);
2135
2136 kcore_copy__for_each_phdr(&kci, p) {
2137 off_t offs = p->rel + offset;
2138
2139 if (kcore__add_phdr(&extract, idx++, offs, p->addr, p->len))
2140 goto out_extract_close;
2141 }
2142
2143 sz = kcore__write(&extract);
2144 if (sz < 0 || sz > offset)
2145 goto out_extract_close;
2146
2147 kcore_copy__for_each_phdr(&kci, p) {
2148 off_t offs = p->rel + offset;
2149
2150 if (p->remaps)
2151 continue;
2152 if (copy_bytes(kcore.fd, p->offset, extract.fd, offs, p->len))
2153 goto out_extract_close;
2154 }
2155
2156 if (kcore_copy__compare_file(from_dir, to_dir, "modules"))
2157 goto out_extract_close;
2158
2159 if (kcore_copy__compare_file(from_dir, to_dir, "kallsyms"))
2160 goto out_extract_close;
2161
2162 err = 0;
2163
2164out_extract_close:
2165 kcore__close(&extract);
2166 if (err)
2167 unlink(extract_filename);
2168out_kcore_close:
2169 kcore__close(&kcore);
2170out_unlink_modules:
2171 if (err)
2172 kcore_copy__unlink(to_dir, "modules");
2173out_unlink_kallsyms:
2174 if (err)
2175 kcore_copy__unlink(to_dir, "kallsyms");
2176
2177 kcore_copy__free_phdrs(&kci);
2178 kcore_copy__free_syms(&kci);
2179
2180 return err;
2181}
2182
2183int kcore_extract__create(struct kcore_extract *kce)
2184{
2185 struct kcore kcore;
2186 struct kcore extract;
2187 size_t count = 1;
2188 int idx = 0, err = -1;
2189 off_t offset = page_size, sz;
2190
2191 if (kcore__open(&kcore, kce->kcore_filename))
2192 return -1;
2193
2194 strcpy(kce->extract_filename, PERF_KCORE_EXTRACT);
2195 if (kcore__init(&extract, kce->extract_filename, kcore.elfclass, true))
2196 goto out_kcore_close;
2197
2198 if (kcore__copy_hdr(&kcore, &extract, count))
2199 goto out_extract_close;
2200
2201 if (kcore__add_phdr(&extract, idx, offset, kce->addr, kce->len))
2202 goto out_extract_close;
2203
2204 sz = kcore__write(&extract);
2205 if (sz < 0 || sz > offset)
2206 goto out_extract_close;
2207
2208 if (copy_bytes(kcore.fd, kce->offs, extract.fd, offset, kce->len))
2209 goto out_extract_close;
2210
2211 err = 0;
2212
2213out_extract_close:
2214 kcore__close(&extract);
2215 if (err)
2216 unlink(kce->extract_filename);
2217out_kcore_close:
2218 kcore__close(&kcore);
2219
2220 return err;
2221}
2222
2223void kcore_extract__delete(struct kcore_extract *kce)
2224{
2225 unlink(kce->extract_filename);
2226}
2227
2228#ifdef HAVE_GELF_GETNOTE_SUPPORT
2229
2230static void sdt_adjust_loc(struct sdt_note *tmp, GElf_Addr base_off)
2231{
2232 if (!base_off)
2233 return;
2234
2235 if (tmp->bit32)
2236 tmp->addr.a32[SDT_NOTE_IDX_LOC] =
2237 tmp->addr.a32[SDT_NOTE_IDX_LOC] + base_off -
2238 tmp->addr.a32[SDT_NOTE_IDX_BASE];
2239 else
2240 tmp->addr.a64[SDT_NOTE_IDX_LOC] =
2241 tmp->addr.a64[SDT_NOTE_IDX_LOC] + base_off -
2242 tmp->addr.a64[SDT_NOTE_IDX_BASE];
2243}
2244
2245static void sdt_adjust_refctr(struct sdt_note *tmp, GElf_Addr base_addr,
2246 GElf_Addr base_off)
2247{
2248 if (!base_off)
2249 return;
2250
2251 if (tmp->bit32 && tmp->addr.a32[SDT_NOTE_IDX_REFCTR])
2252 tmp->addr.a32[SDT_NOTE_IDX_REFCTR] -= (base_addr - base_off);
2253 else if (tmp->addr.a64[SDT_NOTE_IDX_REFCTR])
2254 tmp->addr.a64[SDT_NOTE_IDX_REFCTR] -= (base_addr - base_off);
2255}
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268static int populate_sdt_note(Elf **elf, const char *data, size_t len,
2269 struct list_head *sdt_notes)
2270{
2271 const char *provider, *name, *args;
2272 struct sdt_note *tmp = NULL;
2273 GElf_Ehdr ehdr;
2274 GElf_Shdr shdr;
2275 int ret = -EINVAL;
2276
2277 union {
2278 Elf64_Addr a64[NR_ADDR];
2279 Elf32_Addr a32[NR_ADDR];
2280 } buf;
2281
2282 Elf_Data dst = {
2283 .d_buf = &buf, .d_type = ELF_T_ADDR, .d_version = EV_CURRENT,
2284 .d_size = gelf_fsize((*elf), ELF_T_ADDR, NR_ADDR, EV_CURRENT),
2285 .d_off = 0, .d_align = 0
2286 };
2287 Elf_Data src = {
2288 .d_buf = (void *) data, .d_type = ELF_T_ADDR,
2289 .d_version = EV_CURRENT, .d_size = dst.d_size, .d_off = 0,
2290 .d_align = 0
2291 };
2292
2293 tmp = (struct sdt_note *)calloc(1, sizeof(struct sdt_note));
2294 if (!tmp) {
2295 ret = -ENOMEM;
2296 goto out_err;
2297 }
2298
2299 INIT_LIST_HEAD(&tmp->note_list);
2300
2301 if (len < dst.d_size + 3)
2302 goto out_free_note;
2303
2304
2305 if (gelf_xlatetom(*elf, &dst, &src,
2306 elf_getident(*elf, NULL)[EI_DATA]) == NULL) {
2307 pr_err("gelf_xlatetom : %s\n", elf_errmsg(-1));
2308 goto out_free_note;
2309 }
2310
2311
2312 provider = data + dst.d_size;
2313
2314 name = (const char *)memchr(provider, '\0', data + len - provider);
2315 if (name++ == NULL)
2316 goto out_free_note;
2317
2318 tmp->provider = strdup(provider);
2319 if (!tmp->provider) {
2320 ret = -ENOMEM;
2321 goto out_free_note;
2322 }
2323 tmp->name = strdup(name);
2324 if (!tmp->name) {
2325 ret = -ENOMEM;
2326 goto out_free_prov;
2327 }
2328
2329 args = memchr(name, '\0', data + len - name);
2330
2331
2332
2333
2334
2335
2336
2337 if (args == NULL || data + len - args < 2 ||
2338 args[1] == ':' || args[1] == '\0')
2339 tmp->args = NULL;
2340 else {
2341 tmp->args = strdup(++args);
2342 if (!tmp->args) {
2343 ret = -ENOMEM;
2344 goto out_free_name;
2345 }
2346 }
2347
2348 if (gelf_getclass(*elf) == ELFCLASS32) {
2349 memcpy(&tmp->addr, &buf, 3 * sizeof(Elf32_Addr));
2350 tmp->bit32 = true;
2351 } else {
2352 memcpy(&tmp->addr, &buf, 3 * sizeof(Elf64_Addr));
2353 tmp->bit32 = false;
2354 }
2355
2356 if (!gelf_getehdr(*elf, &ehdr)) {
2357 pr_debug("%s : cannot get elf header.\n", __func__);
2358 ret = -EBADF;
2359 goto out_free_args;
2360 }
2361
2362
2363
2364
2365
2366
2367
2368
2369 if (elf_section_by_name(*elf, &ehdr, &shdr, SDT_BASE_SCN, NULL))
2370 sdt_adjust_loc(tmp, shdr.sh_offset);
2371
2372
2373 if (elf_section_by_name(*elf, &ehdr, &shdr, SDT_PROBES_SCN, NULL))
2374 sdt_adjust_refctr(tmp, shdr.sh_addr, shdr.sh_offset);
2375
2376 list_add_tail(&tmp->note_list, sdt_notes);
2377 return 0;
2378
2379out_free_args:
2380 zfree(&tmp->args);
2381out_free_name:
2382 zfree(&tmp->name);
2383out_free_prov:
2384 zfree(&tmp->provider);
2385out_free_note:
2386 free(tmp);
2387out_err:
2388 return ret;
2389}
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400static int construct_sdt_notes_list(Elf *elf, struct list_head *sdt_notes)
2401{
2402 GElf_Ehdr ehdr;
2403 Elf_Scn *scn = NULL;
2404 Elf_Data *data;
2405 GElf_Shdr shdr;
2406 size_t shstrndx, next;
2407 GElf_Nhdr nhdr;
2408 size_t name_off, desc_off, offset;
2409 int ret = 0;
2410
2411 if (gelf_getehdr(elf, &ehdr) == NULL) {
2412 ret = -EBADF;
2413 goto out_ret;
2414 }
2415 if (elf_getshdrstrndx(elf, &shstrndx) != 0) {
2416 ret = -EBADF;
2417 goto out_ret;
2418 }
2419
2420
2421 scn = elf_section_by_name(elf, &ehdr, &shdr, SDT_NOTE_SCN, NULL);
2422 if (!scn) {
2423 ret = -ENOENT;
2424 goto out_ret;
2425 }
2426
2427 if ((shdr.sh_type != SHT_NOTE) || (shdr.sh_flags & SHF_ALLOC)) {
2428 ret = -ENOENT;
2429 goto out_ret;
2430 }
2431
2432 data = elf_getdata(scn, NULL);
2433
2434
2435 for (offset = 0; (next = gelf_getnote(data, offset, &nhdr, &name_off,
2436 &desc_off)) > 0; offset = next) {
2437 if (nhdr.n_namesz == sizeof(SDT_NOTE_NAME) &&
2438 !memcmp(data->d_buf + name_off, SDT_NOTE_NAME,
2439 sizeof(SDT_NOTE_NAME))) {
2440
2441 if (nhdr.n_type != SDT_NOTE_TYPE)
2442 goto out_ret;
2443
2444 ret = populate_sdt_note(&elf, ((data->d_buf) + desc_off),
2445 nhdr.n_descsz, sdt_notes);
2446 if (ret < 0)
2447 goto out_ret;
2448 }
2449 }
2450 if (list_empty(sdt_notes))
2451 ret = -ENOENT;
2452
2453out_ret:
2454 return ret;
2455}
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465int get_sdt_note_list(struct list_head *head, const char *target)
2466{
2467 Elf *elf;
2468 int fd, ret;
2469
2470 fd = open(target, O_RDONLY);
2471 if (fd < 0)
2472 return -EBADF;
2473
2474 elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
2475 if (!elf) {
2476 ret = -EBADF;
2477 goto out_close;
2478 }
2479 ret = construct_sdt_notes_list(elf, head);
2480 elf_end(elf);
2481out_close:
2482 close(fd);
2483 return ret;
2484}
2485
2486
2487
2488
2489
2490
2491
2492
2493int cleanup_sdt_note_list(struct list_head *sdt_notes)
2494{
2495 struct sdt_note *tmp, *pos;
2496 int nr_free = 0;
2497
2498 list_for_each_entry_safe(pos, tmp, sdt_notes, note_list) {
2499 list_del_init(&pos->note_list);
2500 zfree(&pos->args);
2501 zfree(&pos->name);
2502 zfree(&pos->provider);
2503 free(pos);
2504 nr_free++;
2505 }
2506 return nr_free;
2507}
2508
2509
2510
2511
2512
2513
2514
2515int sdt_notes__get_count(struct list_head *start)
2516{
2517 struct sdt_note *sdt_ptr;
2518 int count = 0;
2519
2520 list_for_each_entry(sdt_ptr, start, note_list)
2521 count++;
2522 return count;
2523}
2524#endif
2525
2526void symbol__elf_init(void)
2527{
2528 elf_version(EV_CURRENT);
2529}
2530