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b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
e5a1845f NK |
2 | #include <fcntl.h> |
3 | #include <stdio.h> | |
4 | #include <errno.h> | |
215a0d30 | 5 | #include <stdlib.h> |
e5a1845f NK |
6 | #include <string.h> |
7 | #include <unistd.h> | |
8 | #include <inttypes.h> | |
9 | ||
09aa3b00 | 10 | #include "dso.h" |
1101f69a | 11 | #include "map.h" |
c54d241b | 12 | #include "maps.h" |
e5a1845f | 13 | #include "symbol.h" |
b1d1b094 | 14 | #include "symsrc.h" |
3b4e4efe | 15 | #include "demangle-cxx.h" |
cef7af25 | 16 | #include "demangle-ocaml.h" |
e9c4bcdd | 17 | #include "demangle-java.h" |
cae15db7 | 18 | #include "demangle-rust.h" |
8fa7d87f | 19 | #include "machine.h" |
922d0e4d | 20 | #include "vdso.h" |
e5a1845f | 21 | #include "debug.h" |
32ff3fec | 22 | #include "util/copyfile.h" |
3052ba56 | 23 | #include <linux/ctype.h> |
fb71c86c | 24 | #include <linux/kernel.h> |
7f7c536f | 25 | #include <linux/zalloc.h> |
94a830d7 | 26 | #include <linux/string.h> |
3d689ed6 | 27 | #include <symbol/kallsyms.h> |
fb71c86c | 28 | #include <internal/lib.h> |
e5a1845f | 29 | |
3b4e4efe IR |
30 | #ifdef HAVE_LIBBFD_SUPPORT |
31 | #define PACKAGE 'perf' | |
32 | #include <bfd.h> | |
33 | #endif | |
34 | ||
65cd8e55 IR |
35 | #if defined(HAVE_LIBBFD_SUPPORT) || defined(HAVE_CPLUS_DEMANGLE_SUPPORT) |
36 | #ifndef DMGL_PARAMS | |
37 | #define DMGL_PARAMS (1 << 0) /* Include function args */ | |
38 | #define DMGL_ANSI (1 << 1) /* Include const, volatile, etc */ | |
39 | #endif | |
40 | #endif | |
41 | ||
e370a3d5 DA |
42 | #ifndef EM_AARCH64 |
43 | #define EM_AARCH64 183 /* ARM 64 bit */ | |
44 | #endif | |
45 | ||
765be32b TY |
46 | #ifndef EM_LOONGARCH |
47 | #define EM_LOONGARCH 258 | |
48 | #endif | |
49 | ||
843cf70e ACM |
50 | #ifndef ELF32_ST_VISIBILITY |
51 | #define ELF32_ST_VISIBILITY(o) ((o) & 0x03) | |
52 | #endif | |
53 | ||
54 | /* For ELF64 the definitions are the same. */ | |
55 | #ifndef ELF64_ST_VISIBILITY | |
56 | #define ELF64_ST_VISIBILITY(o) ELF32_ST_VISIBILITY (o) | |
57 | #endif | |
58 | ||
59 | /* How to extract information held in the st_other field. */ | |
60 | #ifndef GELF_ST_VISIBILITY | |
61 | #define GELF_ST_VISIBILITY(val) ELF64_ST_VISIBILITY (val) | |
62 | #endif | |
63 | ||
cc31078c | 64 | typedef Elf64_Nhdr GElf_Nhdr; |
e370a3d5 | 65 | |
aaba4e12 | 66 | |
89fe808a | 67 | #ifndef HAVE_ELF_GETPHDRNUM_SUPPORT |
179f36dd | 68 | static int elf_getphdrnum(Elf *elf, size_t *dst) |
e955d5c4 AH |
69 | { |
70 | GElf_Ehdr gehdr; | |
71 | GElf_Ehdr *ehdr; | |
72 | ||
73 | ehdr = gelf_getehdr(elf, &gehdr); | |
74 | if (!ehdr) | |
75 | return -1; | |
76 | ||
77 | *dst = ehdr->e_phnum; | |
78 | ||
79 | return 0; | |
80 | } | |
81 | #endif | |
82 | ||
2492c465 ACM |
83 | #ifndef HAVE_ELF_GETSHDRSTRNDX_SUPPORT |
84 | static int elf_getshdrstrndx(Elf *elf __maybe_unused, size_t *dst __maybe_unused) | |
85 | { | |
86 | pr_err("%s: update your libelf to > 0.140, this one lacks elf_getshdrstrndx().\n", __func__); | |
87 | return -1; | |
88 | } | |
89 | #endif | |
90 | ||
e5a1845f NK |
91 | #ifndef NT_GNU_BUILD_ID |
92 | #define NT_GNU_BUILD_ID 3 | |
93 | #endif | |
94 | ||
95 | /** | |
96 | * elf_symtab__for_each_symbol - iterate thru all the symbols | |
97 | * | |
98 | * @syms: struct elf_symtab instance to iterate | |
99 | * @idx: uint32_t idx | |
100 | * @sym: GElf_Sym iterator | |
101 | */ | |
102 | #define elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) \ | |
103 | for (idx = 0, gelf_getsym(syms, idx, &sym);\ | |
104 | idx < nr_syms; \ | |
105 | idx++, gelf_getsym(syms, idx, &sym)) | |
106 | ||
107 | static inline uint8_t elf_sym__type(const GElf_Sym *sym) | |
108 | { | |
109 | return GELF_ST_TYPE(sym->st_info); | |
110 | } | |
111 | ||
59a17706 JO |
112 | static inline uint8_t elf_sym__visibility(const GElf_Sym *sym) |
113 | { | |
114 | return GELF_ST_VISIBILITY(sym->st_other); | |
115 | } | |
116 | ||
4e31050f VL |
117 | #ifndef STT_GNU_IFUNC |
118 | #define STT_GNU_IFUNC 10 | |
119 | #endif | |
120 | ||
e5a1845f NK |
121 | static inline int elf_sym__is_function(const GElf_Sym *sym) |
122 | { | |
a2f3b6bf AH |
123 | return (elf_sym__type(sym) == STT_FUNC || |
124 | elf_sym__type(sym) == STT_GNU_IFUNC) && | |
e5a1845f NK |
125 | sym->st_name != 0 && |
126 | sym->st_shndx != SHN_UNDEF; | |
127 | } | |
128 | ||
129 | static inline bool elf_sym__is_object(const GElf_Sym *sym) | |
130 | { | |
131 | return elf_sym__type(sym) == STT_OBJECT && | |
132 | sym->st_name != 0 && | |
133 | sym->st_shndx != SHN_UNDEF; | |
134 | } | |
135 | ||
136 | static inline int elf_sym__is_label(const GElf_Sym *sym) | |
137 | { | |
138 | return elf_sym__type(sym) == STT_NOTYPE && | |
139 | sym->st_name != 0 && | |
140 | sym->st_shndx != SHN_UNDEF && | |
59a17706 JO |
141 | sym->st_shndx != SHN_ABS && |
142 | elf_sym__visibility(sym) != STV_HIDDEN && | |
143 | elf_sym__visibility(sym) != STV_INTERNAL; | |
e5a1845f NK |
144 | } |
145 | ||
3183f8ca | 146 | static bool elf_sym__filter(GElf_Sym *sym) |
e5a1845f | 147 | { |
3183f8ca | 148 | return elf_sym__is_function(sym) || elf_sym__is_object(sym); |
e5a1845f NK |
149 | } |
150 | ||
151 | static inline const char *elf_sym__name(const GElf_Sym *sym, | |
152 | const Elf_Data *symstrs) | |
153 | { | |
154 | return symstrs->d_buf + sym->st_name; | |
155 | } | |
156 | ||
157 | static inline const char *elf_sec__name(const GElf_Shdr *shdr, | |
158 | const Elf_Data *secstrs) | |
159 | { | |
160 | return secstrs->d_buf + shdr->sh_name; | |
161 | } | |
162 | ||
163 | static inline int elf_sec__is_text(const GElf_Shdr *shdr, | |
164 | const Elf_Data *secstrs) | |
165 | { | |
166 | return strstr(elf_sec__name(shdr, secstrs), "text") != NULL; | |
167 | } | |
168 | ||
169 | static inline bool elf_sec__is_data(const GElf_Shdr *shdr, | |
170 | const Elf_Data *secstrs) | |
171 | { | |
172 | return strstr(elf_sec__name(shdr, secstrs), "data") != NULL; | |
173 | } | |
174 | ||
3183f8ca | 175 | static bool elf_sec__filter(GElf_Shdr *shdr, Elf_Data *secstrs) |
e5a1845f | 176 | { |
ee756ef7 | 177 | return elf_sec__is_text(shdr, secstrs) || |
3183f8ca | 178 | elf_sec__is_data(shdr, secstrs); |
e5a1845f NK |
179 | } |
180 | ||
181 | static size_t elf_addr_to_index(Elf *elf, GElf_Addr addr) | |
182 | { | |
183 | Elf_Scn *sec = NULL; | |
184 | GElf_Shdr shdr; | |
185 | size_t cnt = 1; | |
186 | ||
187 | while ((sec = elf_nextscn(elf, sec)) != NULL) { | |
188 | gelf_getshdr(sec, &shdr); | |
189 | ||
190 | if ((addr >= shdr.sh_addr) && | |
191 | (addr < (shdr.sh_addr + shdr.sh_size))) | |
192 | return cnt; | |
193 | ||
194 | ++cnt; | |
195 | } | |
196 | ||
197 | return -1; | |
198 | } | |
199 | ||
99ca4233 MH |
200 | Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep, |
201 | GElf_Shdr *shp, const char *name, size_t *idx) | |
e5a1845f NK |
202 | { |
203 | Elf_Scn *sec = NULL; | |
204 | size_t cnt = 1; | |
205 | ||
70e79866 | 206 | /* ELF is corrupted/truncated, avoid calling elf_strptr. */ |
49274654 CS |
207 | if (!elf_rawdata(elf_getscn(elf, ep->e_shstrndx), NULL)) |
208 | return NULL; | |
209 | ||
e5a1845f NK |
210 | while ((sec = elf_nextscn(elf, sec)) != NULL) { |
211 | char *str; | |
212 | ||
213 | gelf_getshdr(sec, shp); | |
214 | str = elf_strptr(elf, ep->e_shstrndx, shp->sh_name); | |
155b3a13 | 215 | if (str && !strcmp(name, str)) { |
e5a1845f NK |
216 | if (idx) |
217 | *idx = cnt; | |
155b3a13 | 218 | return sec; |
e5a1845f NK |
219 | } |
220 | ++cnt; | |
221 | } | |
222 | ||
155b3a13 | 223 | return NULL; |
e5a1845f NK |
224 | } |
225 | ||
06ea72a4 NK |
226 | bool filename__has_section(const char *filename, const char *sec) |
227 | { | |
228 | int fd; | |
229 | Elf *elf; | |
230 | GElf_Ehdr ehdr; | |
231 | GElf_Shdr shdr; | |
232 | bool found = false; | |
233 | ||
234 | fd = open(filename, O_RDONLY); | |
235 | if (fd < 0) | |
236 | return false; | |
237 | ||
238 | elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL); | |
239 | if (elf == NULL) | |
240 | goto out; | |
241 | ||
242 | if (gelf_getehdr(elf, &ehdr) == NULL) | |
243 | goto elf_out; | |
244 | ||
245 | found = !!elf_section_by_name(elf, &ehdr, &shdr, sec, NULL); | |
246 | ||
247 | elf_out: | |
248 | elf_end(elf); | |
249 | out: | |
250 | close(fd); | |
251 | return found; | |
252 | } | |
253 | ||
2d86612a LY |
254 | static int elf_read_program_header(Elf *elf, u64 vaddr, GElf_Phdr *phdr) |
255 | { | |
256 | size_t i, phdrnum; | |
257 | u64 sz; | |
258 | ||
259 | if (elf_getphdrnum(elf, &phdrnum)) | |
260 | return -1; | |
261 | ||
262 | for (i = 0; i < phdrnum; i++) { | |
263 | if (gelf_getphdr(elf, i, phdr) == NULL) | |
264 | return -1; | |
265 | ||
266 | if (phdr->p_type != PT_LOAD) | |
267 | continue; | |
268 | ||
269 | sz = max(phdr->p_memsz, phdr->p_filesz); | |
270 | if (!sz) | |
271 | continue; | |
272 | ||
273 | if (vaddr >= phdr->p_vaddr && (vaddr < phdr->p_vaddr + sz)) | |
274 | return 0; | |
275 | } | |
276 | ||
277 | /* Not found any valid program header */ | |
278 | return -1; | |
279 | } | |
280 | ||
2a8d41b4 MW |
281 | static bool want_demangle(bool is_kernel_sym) |
282 | { | |
283 | return is_kernel_sym ? symbol_conf.demangle_kernel : symbol_conf.demangle; | |
284 | } | |
285 | ||
65cd8e55 IR |
286 | /* |
287 | * Demangle C++ function signature, typically replaced by demangle-cxx.cpp | |
288 | * version. | |
289 | */ | |
290 | __weak char *cxx_demangle_sym(const char *str __maybe_unused, bool params __maybe_unused, | |
291 | bool modifiers __maybe_unused) | |
292 | { | |
293 | #ifdef HAVE_LIBBFD_SUPPORT | |
294 | int flags = (params ? DMGL_PARAMS : 0) | (modifiers ? DMGL_ANSI : 0); | |
295 | ||
296 | return bfd_demangle(NULL, str, flags); | |
297 | #elif defined(HAVE_CPLUS_DEMANGLE_SUPPORT) | |
298 | int flags = (params ? DMGL_PARAMS : 0) | (modifiers ? DMGL_ANSI : 0); | |
299 | ||
300 | return cplus_demangle(str, flags); | |
301 | #else | |
302 | return NULL; | |
303 | #endif | |
304 | } | |
305 | ||
2a8d41b4 MW |
306 | static char *demangle_sym(struct dso *dso, int kmodule, const char *elf_name) |
307 | { | |
2a8d41b4 MW |
308 | char *demangled = NULL; |
309 | ||
310 | /* | |
311 | * We need to figure out if the object was created from C++ sources | |
312 | * DWARF DW_compile_unit has this, but we don't always have access | |
313 | * to it... | |
314 | */ | |
ee756ef7 IR |
315 | if (!want_demangle(dso__kernel(dso) || kmodule)) |
316 | return demangled; | |
2a8d41b4 | 317 | |
3b4e4efe | 318 | demangled = cxx_demangle_sym(elf_name, verbose > 0, verbose > 0); |
cef7af25 FH |
319 | if (demangled == NULL) { |
320 | demangled = ocaml_demangle_sym(elf_name); | |
321 | if (demangled == NULL) { | |
322 | demangled = java_demangle_sym(elf_name, JAVA_DEMANGLE_NORET); | |
323 | } | |
324 | } | |
2a8d41b4 MW |
325 | else if (rust_is_mangled(demangled)) |
326 | /* | |
327 | * Input to Rust demangling is the BFD-demangled | |
328 | * name which it Rust-demangles in place. | |
329 | */ | |
330 | rust_demangle_sym(demangled); | |
331 | ||
332 | return demangled; | |
333 | } | |
334 | ||
375a4481 | 335 | struct rel_info { |
78250284 AH |
336 | u32 nr_entries; |
337 | u32 *sorted; | |
375a4481 AH |
338 | bool is_rela; |
339 | Elf_Data *reldata; | |
340 | GElf_Rela rela; | |
341 | GElf_Rel rel; | |
342 | }; | |
343 | ||
344 | static u32 get_rel_symidx(struct rel_info *ri, u32 idx) | |
345 | { | |
78250284 | 346 | idx = ri->sorted ? ri->sorted[idx] : idx; |
375a4481 AH |
347 | if (ri->is_rela) { |
348 | gelf_getrela(ri->reldata, idx, &ri->rela); | |
349 | return GELF_R_SYM(ri->rela.r_info); | |
350 | } | |
351 | gelf_getrel(ri->reldata, idx, &ri->rel); | |
352 | return GELF_R_SYM(ri->rel.r_info); | |
353 | } | |
354 | ||
78250284 AH |
355 | static u64 get_rel_offset(struct rel_info *ri, u32 x) |
356 | { | |
357 | if (ri->is_rela) { | |
358 | GElf_Rela rela; | |
359 | ||
360 | gelf_getrela(ri->reldata, x, &rela); | |
361 | return rela.r_offset; | |
362 | } else { | |
363 | GElf_Rel rel; | |
364 | ||
365 | gelf_getrel(ri->reldata, x, &rel); | |
366 | return rel.r_offset; | |
367 | } | |
368 | } | |
369 | ||
370 | static int rel_cmp(const void *a, const void *b, void *r) | |
371 | { | |
372 | struct rel_info *ri = r; | |
373 | u64 a_offset = get_rel_offset(ri, *(const u32 *)a); | |
374 | u64 b_offset = get_rel_offset(ri, *(const u32 *)b); | |
375 | ||
376 | return a_offset < b_offset ? -1 : (a_offset > b_offset ? 1 : 0); | |
377 | } | |
378 | ||
379 | static int sort_rel(struct rel_info *ri) | |
380 | { | |
381 | size_t sz = sizeof(ri->sorted[0]); | |
382 | u32 i; | |
383 | ||
384 | ri->sorted = calloc(ri->nr_entries, sz); | |
385 | if (!ri->sorted) | |
386 | return -1; | |
387 | for (i = 0; i < ri->nr_entries; i++) | |
388 | ri->sorted[i] = i; | |
389 | qsort_r(ri->sorted, ri->nr_entries, sz, rel_cmp, ri); | |
390 | return 0; | |
391 | } | |
392 | ||
b7dbc0be AH |
393 | /* |
394 | * For x86_64, the GNU linker is putting IFUNC information in the relocation | |
395 | * addend. | |
396 | */ | |
397 | static bool addend_may_be_ifunc(GElf_Ehdr *ehdr, struct rel_info *ri) | |
398 | { | |
399 | return ehdr->e_machine == EM_X86_64 && ri->is_rela && | |
400 | GELF_R_TYPE(ri->rela.r_info) == R_X86_64_IRELATIVE; | |
401 | } | |
402 | ||
403 | static bool get_ifunc_name(Elf *elf, struct dso *dso, GElf_Ehdr *ehdr, | |
404 | struct rel_info *ri, char *buf, size_t buf_sz) | |
405 | { | |
406 | u64 addr = ri->rela.r_addend; | |
407 | struct symbol *sym; | |
408 | GElf_Phdr phdr; | |
409 | ||
410 | if (!addend_may_be_ifunc(ehdr, ri)) | |
411 | return false; | |
412 | ||
413 | if (elf_read_program_header(elf, addr, &phdr)) | |
414 | return false; | |
415 | ||
416 | addr -= phdr.p_vaddr - phdr.p_offset; | |
417 | ||
418 | sym = dso__find_symbol_nocache(dso, addr); | |
419 | ||
420 | /* Expecting the address to be an IFUNC or IFUNC alias */ | |
421 | if (!sym || sym->start != addr || (sym->type != STT_GNU_IFUNC && !sym->ifunc_alias)) | |
422 | return false; | |
423 | ||
424 | snprintf(buf, buf_sz, "%s@plt", sym->name); | |
425 | ||
426 | return true; | |
427 | } | |
428 | ||
78250284 AH |
429 | static void exit_rel(struct rel_info *ri) |
430 | { | |
d729163d | 431 | zfree(&ri->sorted); |
78250284 AH |
432 | } |
433 | ||
b08b20c3 | 434 | static bool get_plt_sizes(struct dso *dso, GElf_Ehdr *ehdr, GElf_Shdr *shdr_plt, |
c2d066c0 AH |
435 | u64 *plt_header_size, u64 *plt_entry_size) |
436 | { | |
437 | switch (ehdr->e_machine) { | |
438 | case EM_ARM: | |
439 | *plt_header_size = 20; | |
440 | *plt_entry_size = 12; | |
b08b20c3 | 441 | return true; |
c2d066c0 AH |
442 | case EM_AARCH64: |
443 | *plt_header_size = 32; | |
444 | *plt_entry_size = 16; | |
b08b20c3 | 445 | return true; |
765be32b TY |
446 | case EM_LOONGARCH: |
447 | *plt_header_size = 32; | |
448 | *plt_entry_size = 16; | |
449 | return true; | |
c2d066c0 AH |
450 | case EM_SPARC: |
451 | *plt_header_size = 48; | |
452 | *plt_entry_size = 12; | |
b08b20c3 | 453 | return true; |
c2d066c0 AH |
454 | case EM_SPARCV9: |
455 | *plt_header_size = 128; | |
456 | *plt_entry_size = 32; | |
b08b20c3 | 457 | return true; |
66fe2d53 AH |
458 | case EM_386: |
459 | case EM_X86_64: | |
460 | *plt_entry_size = shdr_plt->sh_entsize; | |
461 | /* Size is 8 or 16, if not, assume alignment indicates size */ | |
462 | if (*plt_entry_size != 8 && *plt_entry_size != 16) | |
463 | *plt_entry_size = shdr_plt->sh_addralign == 8 ? 8 : 16; | |
464 | *plt_header_size = *plt_entry_size; | |
465 | break; | |
c2d066c0 AH |
466 | default: /* FIXME: s390/alpha/mips/parisc/poperpc/sh/xtensa need to be checked */ |
467 | *plt_header_size = shdr_plt->sh_entsize; | |
468 | *plt_entry_size = shdr_plt->sh_entsize; | |
66fe2d53 | 469 | break; |
c2d066c0 | 470 | } |
66fe2d53 AH |
471 | if (*plt_entry_size) |
472 | return true; | |
ee756ef7 | 473 | pr_debug("Missing PLT entry size for %s\n", dso__long_name(dso)); |
66fe2d53 | 474 | return false; |
c2d066c0 AH |
475 | } |
476 | ||
b2529f82 AH |
477 | static bool machine_is_x86(GElf_Half e_machine) |
478 | { | |
479 | return e_machine == EM_386 || e_machine == EM_X86_64; | |
480 | } | |
481 | ||
ce4c8e79 AH |
482 | struct rela_dyn { |
483 | GElf_Addr offset; | |
484 | u32 sym_idx; | |
485 | }; | |
486 | ||
487 | struct rela_dyn_info { | |
488 | struct dso *dso; | |
489 | Elf_Data *plt_got_data; | |
490 | u32 nr_entries; | |
491 | struct rela_dyn *sorted; | |
492 | Elf_Data *dynsym_data; | |
493 | Elf_Data *dynstr_data; | |
494 | Elf_Data *rela_dyn_data; | |
495 | }; | |
496 | ||
497 | static void exit_rela_dyn(struct rela_dyn_info *di) | |
498 | { | |
d729163d | 499 | zfree(&di->sorted); |
ce4c8e79 AH |
500 | } |
501 | ||
502 | static int cmp_offset(const void *a, const void *b) | |
503 | { | |
504 | const struct rela_dyn *va = a; | |
505 | const struct rela_dyn *vb = b; | |
506 | ||
507 | return va->offset < vb->offset ? -1 : (va->offset > vb->offset ? 1 : 0); | |
508 | } | |
509 | ||
510 | static int sort_rela_dyn(struct rela_dyn_info *di) | |
511 | { | |
512 | u32 i, n; | |
513 | ||
514 | di->sorted = calloc(di->nr_entries, sizeof(di->sorted[0])); | |
515 | if (!di->sorted) | |
516 | return -1; | |
517 | ||
518 | /* Get data for sorting: the offset and symbol index */ | |
519 | for (i = 0, n = 0; i < di->nr_entries; i++) { | |
520 | GElf_Rela rela; | |
521 | u32 sym_idx; | |
522 | ||
523 | gelf_getrela(di->rela_dyn_data, i, &rela); | |
524 | sym_idx = GELF_R_SYM(rela.r_info); | |
525 | if (sym_idx) { | |
526 | di->sorted[n].sym_idx = sym_idx; | |
527 | di->sorted[n].offset = rela.r_offset; | |
528 | n += 1; | |
529 | } | |
530 | } | |
531 | ||
532 | /* Sort by offset */ | |
533 | di->nr_entries = n; | |
534 | qsort(di->sorted, n, sizeof(di->sorted[0]), cmp_offset); | |
535 | ||
536 | return 0; | |
537 | } | |
538 | ||
539 | static void get_rela_dyn_info(Elf *elf, GElf_Ehdr *ehdr, struct rela_dyn_info *di, Elf_Scn *scn) | |
540 | { | |
541 | GElf_Shdr rela_dyn_shdr; | |
542 | GElf_Shdr shdr; | |
543 | ||
544 | di->plt_got_data = elf_getdata(scn, NULL); | |
545 | ||
546 | scn = elf_section_by_name(elf, ehdr, &rela_dyn_shdr, ".rela.dyn", NULL); | |
547 | if (!scn || !rela_dyn_shdr.sh_link || !rela_dyn_shdr.sh_entsize) | |
548 | return; | |
549 | ||
550 | di->nr_entries = rela_dyn_shdr.sh_size / rela_dyn_shdr.sh_entsize; | |
551 | di->rela_dyn_data = elf_getdata(scn, NULL); | |
552 | ||
553 | scn = elf_getscn(elf, rela_dyn_shdr.sh_link); | |
554 | if (!scn || !gelf_getshdr(scn, &shdr) || !shdr.sh_link) | |
555 | return; | |
556 | ||
557 | di->dynsym_data = elf_getdata(scn, NULL); | |
558 | di->dynstr_data = elf_getdata(elf_getscn(elf, shdr.sh_link), NULL); | |
559 | ||
560 | if (!di->plt_got_data || !di->dynstr_data || !di->dynsym_data || !di->rela_dyn_data) | |
561 | return; | |
562 | ||
563 | /* Sort into offset order */ | |
564 | sort_rela_dyn(di); | |
565 | } | |
566 | ||
567 | /* Get instruction displacement from a plt entry for x86_64 */ | |
568 | static u32 get_x86_64_plt_disp(const u8 *p) | |
569 | { | |
570 | u8 endbr64[] = {0xf3, 0x0f, 0x1e, 0xfa}; | |
571 | int n = 0; | |
572 | ||
573 | /* Skip endbr64 */ | |
574 | if (!memcmp(p, endbr64, sizeof(endbr64))) | |
575 | n += sizeof(endbr64); | |
576 | /* Skip bnd prefix */ | |
577 | if (p[n] == 0xf2) | |
578 | n += 1; | |
579 | /* jmp with 4-byte displacement */ | |
580 | if (p[n] == 0xff && p[n + 1] == 0x25) { | |
a2410b57 AH |
581 | u32 disp; |
582 | ||
ce4c8e79 AH |
583 | n += 2; |
584 | /* Also add offset from start of entry to end of instruction */ | |
a2410b57 AH |
585 | memcpy(&disp, p + n, sizeof(disp)); |
586 | return n + 4 + le32toh(disp); | |
ce4c8e79 AH |
587 | } |
588 | return 0; | |
589 | } | |
590 | ||
591 | static bool get_plt_got_name(GElf_Shdr *shdr, size_t i, | |
592 | struct rela_dyn_info *di, | |
593 | char *buf, size_t buf_sz) | |
594 | { | |
595 | struct rela_dyn vi, *vr; | |
596 | const char *sym_name; | |
597 | char *demangled; | |
598 | GElf_Sym sym; | |
c8bb2d76 | 599 | bool result; |
ce4c8e79 AH |
600 | u32 disp; |
601 | ||
602 | if (!di->sorted) | |
603 | return false; | |
604 | ||
605 | disp = get_x86_64_plt_disp(di->plt_got_data->d_buf + i); | |
606 | if (!disp) | |
607 | return false; | |
608 | ||
609 | /* Compute target offset of the .plt.got entry */ | |
610 | vi.offset = shdr->sh_offset + di->plt_got_data->d_off + i + disp; | |
611 | ||
612 | /* Find that offset in .rela.dyn (sorted by offset) */ | |
613 | vr = bsearch(&vi, di->sorted, di->nr_entries, sizeof(di->sorted[0]), cmp_offset); | |
614 | if (!vr) | |
615 | return false; | |
616 | ||
617 | /* Get the associated symbol */ | |
618 | gelf_getsym(di->dynsym_data, vr->sym_idx, &sym); | |
619 | sym_name = elf_sym__name(&sym, di->dynstr_data); | |
620 | demangled = demangle_sym(di->dso, 0, sym_name); | |
621 | if (demangled != NULL) | |
622 | sym_name = demangled; | |
623 | ||
624 | snprintf(buf, buf_sz, "%s@plt", sym_name); | |
625 | ||
c8bb2d76 AH |
626 | result = *sym_name; |
627 | ||
ce4c8e79 AH |
628 | free(demangled); |
629 | ||
c8bb2d76 | 630 | return result; |
ce4c8e79 AH |
631 | } |
632 | ||
51a188ad AH |
633 | static int dso__synthesize_plt_got_symbols(struct dso *dso, Elf *elf, |
634 | GElf_Ehdr *ehdr, | |
635 | char *buf, size_t buf_sz) | |
636 | { | |
ce4c8e79 | 637 | struct rela_dyn_info di = { .dso = dso }; |
51a188ad AH |
638 | struct symbol *sym; |
639 | GElf_Shdr shdr; | |
640 | Elf_Scn *scn; | |
ce4c8e79 | 641 | int err = -1; |
51a188ad AH |
642 | size_t i; |
643 | ||
644 | scn = elf_section_by_name(elf, ehdr, &shdr, ".plt.got", NULL); | |
645 | if (!scn || !shdr.sh_entsize) | |
646 | return 0; | |
647 | ||
ce4c8e79 AH |
648 | if (ehdr->e_machine == EM_X86_64) |
649 | get_rela_dyn_info(elf, ehdr, &di, scn); | |
650 | ||
51a188ad | 651 | for (i = 0; i < shdr.sh_size; i += shdr.sh_entsize) { |
ce4c8e79 AH |
652 | if (!get_plt_got_name(&shdr, i, &di, buf, buf_sz)) |
653 | snprintf(buf, buf_sz, "offset_%#" PRIx64 "@plt", (u64)shdr.sh_offset + i); | |
51a188ad AH |
654 | sym = symbol__new(shdr.sh_offset + i, shdr.sh_entsize, STB_GLOBAL, STT_FUNC, buf); |
655 | if (!sym) | |
ce4c8e79 | 656 | goto out; |
ee756ef7 | 657 | symbols__insert(dso__symbols(dso), sym); |
51a188ad | 658 | } |
ce4c8e79 AH |
659 | err = 0; |
660 | out: | |
661 | exit_rela_dyn(&di); | |
662 | return err; | |
51a188ad AH |
663 | } |
664 | ||
e5a1845f NK |
665 | /* |
666 | * We need to check if we have a .dynsym, so that we can handle the | |
667 | * .plt, synthesizing its symbols, that aren't on the symtabs (be it | |
668 | * .dynsym or .symtab). | |
669 | * And always look at the original dso, not at debuginfo packages, that | |
670 | * have the PLT data stripped out (shdr_rel_plt.sh_type == SHT_NOBITS). | |
671 | */ | |
3183f8ca | 672 | int dso__synthesize_plt_symbols(struct dso *dso, struct symsrc *ss) |
e5a1845f | 673 | { |
78250284 | 674 | uint32_t idx; |
e5a1845f | 675 | GElf_Sym sym; |
b2f76050 | 676 | u64 plt_offset, plt_header_size, plt_entry_size; |
b2529f82 AH |
677 | GElf_Shdr shdr_plt, plt_sec_shdr; |
678 | struct symbol *f, *plt_sym; | |
e5a1845f | 679 | GElf_Shdr shdr_rel_plt, shdr_dynsym; |
375a4481 | 680 | Elf_Data *syms, *symstrs; |
e5a1845f | 681 | Elf_Scn *scn_plt_rel, *scn_symstrs, *scn_dynsym; |
e5a1845f NK |
682 | GElf_Ehdr ehdr; |
683 | char sympltname[1024]; | |
684 | Elf *elf; | |
375a4481 AH |
685 | int nr = 0, err = -1; |
686 | struct rel_info ri = { .is_rela = false }; | |
60fbb3e4 | 687 | bool lazy_plt; |
e5a1845f | 688 | |
a44f605b CS |
689 | elf = ss->elf; |
690 | ehdr = ss->ehdr; | |
e5a1845f | 691 | |
698a0d1a AH |
692 | if (!elf_section_by_name(elf, &ehdr, &shdr_plt, ".plt", NULL)) |
693 | return 0; | |
694 | ||
695 | /* | |
696 | * A symbol from a previous section (e.g. .init) can have been expanded | |
697 | * by symbols__fixup_end() to overlap .plt. Truncate it before adding | |
698 | * a symbol for .plt header. | |
699 | */ | |
700 | f = dso__find_symbol_nocache(dso, shdr_plt.sh_offset); | |
701 | if (f && f->start < shdr_plt.sh_offset && f->end > shdr_plt.sh_offset) | |
702 | f->end = shdr_plt.sh_offset; | |
703 | ||
704 | if (!get_plt_sizes(dso, &ehdr, &shdr_plt, &plt_header_size, &plt_entry_size)) | |
705 | return 0; | |
706 | ||
707 | /* Add a symbol for .plt header */ | |
b2529f82 AH |
708 | plt_sym = symbol__new(shdr_plt.sh_offset, plt_header_size, STB_GLOBAL, STT_FUNC, ".plt"); |
709 | if (!plt_sym) | |
698a0d1a | 710 | goto out_elf_end; |
ee756ef7 | 711 | symbols__insert(dso__symbols(dso), plt_sym); |
b2529f82 | 712 | |
51a188ad AH |
713 | /* Only x86 has .plt.got */ |
714 | if (machine_is_x86(ehdr.e_machine) && | |
715 | dso__synthesize_plt_got_symbols(dso, elf, &ehdr, sympltname, sizeof(sympltname))) | |
716 | goto out_elf_end; | |
717 | ||
b2529f82 AH |
718 | /* Only x86 has .plt.sec */ |
719 | if (machine_is_x86(ehdr.e_machine) && | |
720 | elf_section_by_name(elf, &ehdr, &plt_sec_shdr, ".plt.sec", NULL)) { | |
721 | if (!get_plt_sizes(dso, &ehdr, &plt_sec_shdr, &plt_header_size, &plt_entry_size)) | |
722 | return 0; | |
723 | /* Extend .plt symbol to entire .plt */ | |
724 | plt_sym->end = plt_sym->start + shdr_plt.sh_size; | |
725 | /* Use .plt.sec offset */ | |
726 | plt_offset = plt_sec_shdr.sh_offset; | |
60fbb3e4 | 727 | lazy_plt = false; |
b2529f82 | 728 | } else { |
60fbb3e4 AH |
729 | plt_offset = shdr_plt.sh_offset; |
730 | lazy_plt = true; | |
b2529f82 | 731 | } |
698a0d1a | 732 | |
e5a1845f NK |
733 | scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt, |
734 | ".rela.plt", NULL); | |
735 | if (scn_plt_rel == NULL) { | |
736 | scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt, | |
737 | ".rel.plt", NULL); | |
738 | if (scn_plt_rel == NULL) | |
477d5e35 | 739 | return 0; |
e5a1845f NK |
740 | } |
741 | ||
df8aeaef AH |
742 | if (shdr_rel_plt.sh_type != SHT_RELA && |
743 | shdr_rel_plt.sh_type != SHT_REL) | |
744 | return 0; | |
745 | ||
a1ab1285 AH |
746 | if (!shdr_rel_plt.sh_link) |
747 | return 0; | |
748 | ||
749 | if (shdr_rel_plt.sh_link == ss->dynsym_idx) { | |
750 | scn_dynsym = ss->dynsym; | |
751 | shdr_dynsym = ss->dynshdr; | |
752 | } else if (shdr_rel_plt.sh_link == ss->symtab_idx) { | |
753 | /* | |
754 | * A static executable can have a .plt due to IFUNCs, in which | |
755 | * case .symtab is used not .dynsym. | |
756 | */ | |
757 | scn_dynsym = ss->symtab; | |
758 | shdr_dynsym = ss->symshdr; | |
759 | } else { | |
e5a1845f | 760 | goto out_elf_end; |
a1ab1285 AH |
761 | } |
762 | ||
763 | if (!scn_dynsym) | |
764 | return 0; | |
e5a1845f | 765 | |
e5a1845f NK |
766 | /* |
767 | * Fetch the relocation section to find the idxes to the GOT | |
768 | * and the symbols in the .dynsym they refer to. | |
769 | */ | |
375a4481 AH |
770 | ri.reldata = elf_getdata(scn_plt_rel, NULL); |
771 | if (!ri.reldata) | |
e5a1845f NK |
772 | goto out_elf_end; |
773 | ||
774 | syms = elf_getdata(scn_dynsym, NULL); | |
775 | if (syms == NULL) | |
776 | goto out_elf_end; | |
777 | ||
778 | scn_symstrs = elf_getscn(elf, shdr_dynsym.sh_link); | |
779 | if (scn_symstrs == NULL) | |
780 | goto out_elf_end; | |
781 | ||
782 | symstrs = elf_getdata(scn_symstrs, NULL); | |
783 | if (symstrs == NULL) | |
784 | goto out_elf_end; | |
785 | ||
52f9ddba CS |
786 | if (symstrs->d_size == 0) |
787 | goto out_elf_end; | |
788 | ||
78250284 | 789 | ri.nr_entries = shdr_rel_plt.sh_size / shdr_rel_plt.sh_entsize; |
e5a1845f | 790 | |
375a4481 | 791 | ri.is_rela = shdr_rel_plt.sh_type == SHT_RELA; |
e5a1845f | 792 | |
60fbb3e4 AH |
793 | if (lazy_plt) { |
794 | /* | |
795 | * Assume a .plt with the same number of entries as the number | |
796 | * of relocation entries is not lazy and does not have a header. | |
797 | */ | |
798 | if (ri.nr_entries * plt_entry_size == shdr_plt.sh_size) | |
799 | dso__delete_symbol(dso, plt_sym); | |
800 | else | |
801 | plt_offset += plt_header_size; | |
802 | } | |
803 | ||
78250284 AH |
804 | /* |
805 | * x86 doesn't insert IFUNC relocations in .plt order, so sort to get | |
806 | * back in order. | |
807 | */ | |
808 | if (machine_is_x86(ehdr.e_machine) && sort_rel(&ri)) | |
809 | goto out_elf_end; | |
810 | ||
811 | for (idx = 0; idx < ri.nr_entries; idx++) { | |
df8aeaef AH |
812 | const char *elf_name = NULL; |
813 | char *demangled = NULL; | |
814 | ||
815 | gelf_getsym(syms, get_rel_symidx(&ri, idx), &sym); | |
816 | ||
817 | elf_name = elf_sym__name(&sym, symstrs); | |
818 | demangled = demangle_sym(dso, 0, elf_name); | |
819 | if (demangled) | |
820 | elf_name = demangled; | |
821 | if (*elf_name) | |
822 | snprintf(sympltname, sizeof(sympltname), "%s@plt", elf_name); | |
b7dbc0be | 823 | else if (!get_ifunc_name(elf, dso, &ehdr, &ri, sympltname, sizeof(sympltname))) |
df8aeaef AH |
824 | snprintf(sympltname, sizeof(sympltname), |
825 | "offset_%#" PRIx64 "@plt", plt_offset); | |
826 | free(demangled); | |
827 | ||
828 | f = symbol__new(plt_offset, plt_entry_size, STB_GLOBAL, STT_FUNC, sympltname); | |
829 | if (!f) | |
830 | goto out_elf_end; | |
831 | ||
832 | plt_offset += plt_entry_size; | |
ee756ef7 | 833 | symbols__insert(dso__symbols(dso), f); |
df8aeaef | 834 | ++nr; |
e5a1845f NK |
835 | } |
836 | ||
837 | err = 0; | |
838 | out_elf_end: | |
78250284 | 839 | exit_rel(&ri); |
e5a1845f NK |
840 | if (err == 0) |
841 | return nr; | |
e5a1845f | 842 | pr_debug("%s: problems reading %s PLT info.\n", |
ee756ef7 | 843 | __func__, dso__long_name(dso)); |
e5a1845f NK |
844 | return 0; |
845 | } | |
846 | ||
80c345b2 | 847 | char *dso__demangle_sym(struct dso *dso, int kmodule, const char *elf_name) |
a64489c5 JY |
848 | { |
849 | return demangle_sym(dso, kmodule, elf_name); | |
850 | } | |
851 | ||
e5a1845f NK |
852 | /* |
853 | * Align offset to 4 bytes as needed for note name and descriptor data. | |
854 | */ | |
855 | #define NOTE_ALIGN(n) (((n) + 3) & -4U) | |
856 | ||
857 | static int elf_read_build_id(Elf *elf, void *bf, size_t size) | |
858 | { | |
859 | int err = -1; | |
860 | GElf_Ehdr ehdr; | |
861 | GElf_Shdr shdr; | |
862 | Elf_Data *data; | |
863 | Elf_Scn *sec; | |
864 | Elf_Kind ek; | |
865 | void *ptr; | |
866 | ||
867 | if (size < BUILD_ID_SIZE) | |
868 | goto out; | |
869 | ||
870 | ek = elf_kind(elf); | |
871 | if (ek != ELF_K_ELF) | |
872 | goto out; | |
873 | ||
874 | if (gelf_getehdr(elf, &ehdr) == NULL) { | |
875 | pr_err("%s: cannot get elf header.\n", __func__); | |
876 | goto out; | |
877 | } | |
878 | ||
879 | /* | |
880 | * Check following sections for notes: | |
881 | * '.note.gnu.build-id' | |
882 | * '.notes' | |
883 | * '.note' (VDSO specific) | |
884 | */ | |
885 | do { | |
886 | sec = elf_section_by_name(elf, &ehdr, &shdr, | |
887 | ".note.gnu.build-id", NULL); | |
888 | if (sec) | |
889 | break; | |
890 | ||
891 | sec = elf_section_by_name(elf, &ehdr, &shdr, | |
892 | ".notes", NULL); | |
893 | if (sec) | |
894 | break; | |
895 | ||
896 | sec = elf_section_by_name(elf, &ehdr, &shdr, | |
897 | ".note", NULL); | |
898 | if (sec) | |
899 | break; | |
900 | ||
901 | return err; | |
902 | ||
903 | } while (0); | |
904 | ||
905 | data = elf_getdata(sec, NULL); | |
906 | if (data == NULL) | |
907 | goto out; | |
908 | ||
909 | ptr = data->d_buf; | |
910 | while (ptr < (data->d_buf + data->d_size)) { | |
911 | GElf_Nhdr *nhdr = ptr; | |
912 | size_t namesz = NOTE_ALIGN(nhdr->n_namesz), | |
913 | descsz = NOTE_ALIGN(nhdr->n_descsz); | |
914 | const char *name; | |
915 | ||
916 | ptr += sizeof(*nhdr); | |
917 | name = ptr; | |
918 | ptr += namesz; | |
919 | if (nhdr->n_type == NT_GNU_BUILD_ID && | |
920 | nhdr->n_namesz == sizeof("GNU")) { | |
921 | if (memcmp(name, "GNU", sizeof("GNU")) == 0) { | |
922 | size_t sz = min(size, descsz); | |
923 | memcpy(bf, ptr, sz); | |
924 | memset(bf + sz, 0, size - sz); | |
1511e469 | 925 | err = sz; |
e5a1845f NK |
926 | break; |
927 | } | |
928 | } | |
929 | ptr += descsz; | |
930 | } | |
931 | ||
932 | out: | |
933 | return err; | |
934 | } | |
935 | ||
ba0509dc RB |
936 | #ifdef HAVE_LIBBFD_BUILDID_SUPPORT |
937 | ||
47dce51a | 938 | static int read_build_id(const char *filename, struct build_id *bid) |
ba0509dc | 939 | { |
f766819c | 940 | size_t size = sizeof(bid->data); |
ba0509dc RB |
941 | int err = -1; |
942 | bfd *abfd; | |
943 | ||
944 | abfd = bfd_openr(filename, NULL); | |
945 | if (!abfd) | |
946 | return -1; | |
947 | ||
948 | if (!bfd_check_format(abfd, bfd_object)) { | |
949 | pr_debug2("%s: cannot read %s bfd file.\n", __func__, filename); | |
950 | goto out_close; | |
951 | } | |
952 | ||
953 | if (!abfd->build_id || abfd->build_id->size > size) | |
954 | goto out_close; | |
955 | ||
f766819c JO |
956 | memcpy(bid->data, abfd->build_id->data, abfd->build_id->size); |
957 | memset(bid->data + abfd->build_id->size, 0, size - abfd->build_id->size); | |
958 | err = bid->size = abfd->build_id->size; | |
ba0509dc RB |
959 | |
960 | out_close: | |
961 | bfd_close(abfd); | |
962 | return err; | |
963 | } | |
964 | ||
965 | #else // HAVE_LIBBFD_BUILDID_SUPPORT | |
966 | ||
47dce51a | 967 | static int read_build_id(const char *filename, struct build_id *bid) |
e5a1845f | 968 | { |
f766819c | 969 | size_t size = sizeof(bid->data); |
e5a1845f NK |
970 | int fd, err = -1; |
971 | Elf *elf; | |
972 | ||
973 | if (size < BUILD_ID_SIZE) | |
974 | goto out; | |
975 | ||
976 | fd = open(filename, O_RDONLY); | |
977 | if (fd < 0) | |
978 | goto out; | |
979 | ||
980 | elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL); | |
981 | if (elf == NULL) { | |
982 | pr_debug2("%s: cannot read %s ELF file.\n", __func__, filename); | |
983 | goto out_close; | |
984 | } | |
985 | ||
f766819c JO |
986 | err = elf_read_build_id(elf, bid->data, size); |
987 | if (err > 0) | |
988 | bid->size = err; | |
e5a1845f NK |
989 | |
990 | elf_end(elf); | |
991 | out_close: | |
992 | close(fd); | |
993 | out: | |
994 | return err; | |
995 | } | |
996 | ||
ba0509dc RB |
997 | #endif // HAVE_LIBBFD_BUILDID_SUPPORT |
998 | ||
47dce51a JO |
999 | int filename__read_build_id(const char *filename, struct build_id *bid) |
1000 | { | |
1001 | struct kmod_path m = { .name = NULL, }; | |
1002 | char path[PATH_MAX]; | |
1003 | int err; | |
1004 | ||
1005 | if (!filename) | |
1006 | return -EFAULT; | |
1007 | ||
1008 | err = kmod_path__parse(&m, filename); | |
1009 | if (err) | |
1010 | return -1; | |
1011 | ||
1012 | if (m.comp) { | |
1013 | int error = 0, fd; | |
1014 | ||
1015 | fd = filename__decompress(filename, path, sizeof(path), m.comp, &error); | |
1016 | if (fd < 0) { | |
1017 | pr_debug("Failed to decompress (error %d) %s\n", | |
1018 | error, filename); | |
1019 | return -1; | |
1020 | } | |
1021 | close(fd); | |
1022 | filename = path; | |
1023 | } | |
1024 | ||
1025 | err = read_build_id(filename, bid); | |
1026 | ||
1027 | if (m.comp) | |
1028 | unlink(filename); | |
1029 | return err; | |
1030 | } | |
1031 | ||
3ff1b8c8 | 1032 | int sysfs__read_build_id(const char *filename, struct build_id *bid) |
e5a1845f | 1033 | { |
3ff1b8c8 | 1034 | size_t size = sizeof(bid->data); |
e5a1845f NK |
1035 | int fd, err = -1; |
1036 | ||
e5a1845f NK |
1037 | fd = open(filename, O_RDONLY); |
1038 | if (fd < 0) | |
1039 | goto out; | |
1040 | ||
1041 | while (1) { | |
1042 | char bf[BUFSIZ]; | |
1043 | GElf_Nhdr nhdr; | |
1044 | size_t namesz, descsz; | |
1045 | ||
1046 | if (read(fd, &nhdr, sizeof(nhdr)) != sizeof(nhdr)) | |
1047 | break; | |
1048 | ||
1049 | namesz = NOTE_ALIGN(nhdr.n_namesz); | |
1050 | descsz = NOTE_ALIGN(nhdr.n_descsz); | |
1051 | if (nhdr.n_type == NT_GNU_BUILD_ID && | |
1052 | nhdr.n_namesz == sizeof("GNU")) { | |
1053 | if (read(fd, bf, namesz) != (ssize_t)namesz) | |
1054 | break; | |
1055 | if (memcmp(bf, "GNU", sizeof("GNU")) == 0) { | |
1056 | size_t sz = min(descsz, size); | |
3ff1b8c8 JO |
1057 | if (read(fd, bid->data, sz) == (ssize_t)sz) { |
1058 | memset(bid->data + sz, 0, size - sz); | |
1059 | bid->size = sz; | |
e5a1845f NK |
1060 | err = 0; |
1061 | break; | |
1062 | } | |
1063 | } else if (read(fd, bf, descsz) != (ssize_t)descsz) | |
1064 | break; | |
1065 | } else { | |
1066 | int n = namesz + descsz; | |
7934c98a ACM |
1067 | |
1068 | if (n > (int)sizeof(bf)) { | |
1069 | n = sizeof(bf); | |
1070 | pr_debug("%s: truncating reading of build id in sysfs file %s: n_namesz=%u, n_descsz=%u.\n", | |
1071 | __func__, filename, nhdr.n_namesz, nhdr.n_descsz); | |
1072 | } | |
e5a1845f NK |
1073 | if (read(fd, bf, n) != n) |
1074 | break; | |
1075 | } | |
1076 | } | |
1077 | close(fd); | |
1078 | out: | |
1079 | return err; | |
1080 | } | |
1081 | ||
ba0509dc RB |
1082 | #ifdef HAVE_LIBBFD_SUPPORT |
1083 | ||
1084 | int filename__read_debuglink(const char *filename, char *debuglink, | |
1085 | size_t size) | |
1086 | { | |
1087 | int err = -1; | |
1088 | asection *section; | |
1089 | bfd *abfd; | |
1090 | ||
1091 | abfd = bfd_openr(filename, NULL); | |
1092 | if (!abfd) | |
1093 | return -1; | |
1094 | ||
1095 | if (!bfd_check_format(abfd, bfd_object)) { | |
1096 | pr_debug2("%s: cannot read %s bfd file.\n", __func__, filename); | |
1097 | goto out_close; | |
1098 | } | |
1099 | ||
1100 | section = bfd_get_section_by_name(abfd, ".gnu_debuglink"); | |
1101 | if (!section) | |
1102 | goto out_close; | |
1103 | ||
1104 | if (section->size > size) | |
1105 | goto out_close; | |
1106 | ||
1107 | if (!bfd_get_section_contents(abfd, section, debuglink, 0, | |
1108 | section->size)) | |
1109 | goto out_close; | |
1110 | ||
1111 | err = 0; | |
1112 | ||
1113 | out_close: | |
1114 | bfd_close(abfd); | |
1115 | return err; | |
1116 | } | |
1117 | ||
1118 | #else | |
1119 | ||
e5a1845f NK |
1120 | int filename__read_debuglink(const char *filename, char *debuglink, |
1121 | size_t size) | |
1122 | { | |
1123 | int fd, err = -1; | |
1124 | Elf *elf; | |
1125 | GElf_Ehdr ehdr; | |
1126 | GElf_Shdr shdr; | |
1127 | Elf_Data *data; | |
1128 | Elf_Scn *sec; | |
1129 | Elf_Kind ek; | |
1130 | ||
1131 | fd = open(filename, O_RDONLY); | |
1132 | if (fd < 0) | |
1133 | goto out; | |
1134 | ||
1135 | elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL); | |
1136 | if (elf == NULL) { | |
1137 | pr_debug2("%s: cannot read %s ELF file.\n", __func__, filename); | |
1138 | goto out_close; | |
1139 | } | |
1140 | ||
1141 | ek = elf_kind(elf); | |
1142 | if (ek != ELF_K_ELF) | |
784f3390 | 1143 | goto out_elf_end; |
e5a1845f NK |
1144 | |
1145 | if (gelf_getehdr(elf, &ehdr) == NULL) { | |
1146 | pr_err("%s: cannot get elf header.\n", __func__); | |
784f3390 | 1147 | goto out_elf_end; |
e5a1845f NK |
1148 | } |
1149 | ||
1150 | sec = elf_section_by_name(elf, &ehdr, &shdr, | |
1151 | ".gnu_debuglink", NULL); | |
1152 | if (sec == NULL) | |
784f3390 | 1153 | goto out_elf_end; |
e5a1845f NK |
1154 | |
1155 | data = elf_getdata(sec, NULL); | |
1156 | if (data == NULL) | |
784f3390 | 1157 | goto out_elf_end; |
e5a1845f NK |
1158 | |
1159 | /* the start of this section is a zero-terminated string */ | |
1160 | strncpy(debuglink, data->d_buf, size); | |
1161 | ||
0d3dc5e8 SE |
1162 | err = 0; |
1163 | ||
784f3390 | 1164 | out_elf_end: |
e5a1845f | 1165 | elf_end(elf); |
e5a1845f NK |
1166 | out_close: |
1167 | close(fd); | |
1168 | out: | |
1169 | return err; | |
1170 | } | |
1171 | ||
ba0509dc RB |
1172 | #endif |
1173 | ||
e5a1845f NK |
1174 | static int dso__swap_init(struct dso *dso, unsigned char eidata) |
1175 | { | |
1176 | static unsigned int const endian = 1; | |
1177 | ||
ee756ef7 | 1178 | dso__set_needs_swap(dso, DSO_SWAP__NO); |
e5a1845f NK |
1179 | |
1180 | switch (eidata) { | |
1181 | case ELFDATA2LSB: | |
1182 | /* We are big endian, DSO is little endian. */ | |
1183 | if (*(unsigned char const *)&endian != 1) | |
ee756ef7 | 1184 | dso__set_needs_swap(dso, DSO_SWAP__YES); |
e5a1845f NK |
1185 | break; |
1186 | ||
1187 | case ELFDATA2MSB: | |
1188 | /* We are little endian, DSO is big endian. */ | |
1189 | if (*(unsigned char const *)&endian != 0) | |
ee756ef7 | 1190 | dso__set_needs_swap(dso, DSO_SWAP__YES); |
e5a1845f NK |
1191 | break; |
1192 | ||
1193 | default: | |
1194 | pr_err("unrecognized DSO data encoding %d\n", eidata); | |
1195 | return -EINVAL; | |
1196 | } | |
1197 | ||
1198 | return 0; | |
1199 | } | |
1200 | ||
3aafe5ae CS |
1201 | bool symsrc__possibly_runtime(struct symsrc *ss) |
1202 | { | |
1203 | return ss->dynsym || ss->opdsec; | |
1204 | } | |
1205 | ||
d26cd12b CS |
1206 | bool symsrc__has_symtab(struct symsrc *ss) |
1207 | { | |
1208 | return ss->symtab != NULL; | |
1209 | } | |
b68e2f91 CS |
1210 | |
1211 | void symsrc__destroy(struct symsrc *ss) | |
1212 | { | |
74cf249d | 1213 | zfree(&ss->name); |
b68e2f91 CS |
1214 | elf_end(ss->elf); |
1215 | close(ss->fd); | |
1216 | } | |
1217 | ||
7eec00a7 | 1218 | bool elf__needs_adjust_symbols(GElf_Ehdr ehdr) |
d2332098 | 1219 | { |
7eec00a7 LY |
1220 | /* |
1221 | * Usually vmlinux is an ELF file with type ET_EXEC for most | |
1222 | * architectures; except Arm64 kernel is linked with option | |
1223 | * '-share', so need to check type ET_DYN. | |
1224 | */ | |
1225 | return ehdr.e_type == ET_EXEC || ehdr.e_type == ET_REL || | |
1226 | ehdr.e_type == ET_DYN; | |
d2332098 NR |
1227 | } |
1228 | ||
b68e2f91 CS |
1229 | int symsrc__init(struct symsrc *ss, struct dso *dso, const char *name, |
1230 | enum dso_binary_type type) | |
e5a1845f | 1231 | { |
e5a1845f | 1232 | GElf_Ehdr ehdr; |
e5a1845f | 1233 | Elf *elf; |
b68e2f91 CS |
1234 | int fd; |
1235 | ||
18425f13 | 1236 | if (dso__needs_decompress(dso)) { |
42b3fa67 | 1237 | fd = dso__decompress_kmodule_fd(dso, name); |
18425f13 ACM |
1238 | if (fd < 0) |
1239 | return -1; | |
c25ec42f | 1240 | |
ee756ef7 | 1241 | type = dso__symtab_type(dso); |
18425f13 | 1242 | } else { |
c00c48fc | 1243 | fd = open(name, O_RDONLY); |
18425f13 | 1244 | if (fd < 0) { |
ee756ef7 | 1245 | *dso__load_errno(dso) = errno; |
18425f13 ACM |
1246 | return -1; |
1247 | } | |
1248 | } | |
e5a1845f NK |
1249 | |
1250 | elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL); | |
1251 | if (elf == NULL) { | |
1252 | pr_debug("%s: cannot read %s ELF file.\n", __func__, name); | |
ee756ef7 | 1253 | *dso__load_errno(dso) = DSO_LOAD_ERRNO__INVALID_ELF; |
e5a1845f NK |
1254 | goto out_close; |
1255 | } | |
1256 | ||
1257 | if (gelf_getehdr(elf, &ehdr) == NULL) { | |
ee756ef7 | 1258 | *dso__load_errno(dso) = DSO_LOAD_ERRNO__INVALID_ELF; |
e5a1845f NK |
1259 | pr_debug("%s: cannot get elf header.\n", __func__); |
1260 | goto out_elf_end; | |
1261 | } | |
1262 | ||
18425f13 | 1263 | if (dso__swap_init(dso, ehdr.e_ident[EI_DATA])) { |
ee756ef7 | 1264 | *dso__load_errno(dso) = DSO_LOAD_ERRNO__INTERNAL_ERROR; |
e5a1845f | 1265 | goto out_elf_end; |
18425f13 | 1266 | } |
e5a1845f NK |
1267 | |
1268 | /* Always reject images with a mismatched build-id: */ | |
ee756ef7 | 1269 | if (dso__has_build_id(dso) && !symbol_conf.ignore_vmlinux_buildid) { |
e5a1845f | 1270 | u8 build_id[BUILD_ID_SIZE]; |
39be8d01 JO |
1271 | struct build_id bid; |
1272 | int size; | |
e5a1845f | 1273 | |
39be8d01 JO |
1274 | size = elf_read_build_id(elf, build_id, BUILD_ID_SIZE); |
1275 | if (size <= 0) { | |
ee756ef7 | 1276 | *dso__load_errno(dso) = DSO_LOAD_ERRNO__CANNOT_READ_BUILDID; |
e5a1845f | 1277 | goto out_elf_end; |
18425f13 | 1278 | } |
e5a1845f | 1279 | |
39be8d01 JO |
1280 | build_id__init(&bid, build_id, size); |
1281 | if (!dso__build_id_equal(dso, &bid)) { | |
468f3d29 | 1282 | pr_debug("%s: build id mismatch for %s.\n", __func__, name); |
ee756ef7 | 1283 | *dso__load_errno(dso) = DSO_LOAD_ERRNO__MISMATCHING_BUILDID; |
e5a1845f | 1284 | goto out_elf_end; |
18425f13 | 1285 | } |
e5a1845f NK |
1286 | } |
1287 | ||
c6d8f2a4 AH |
1288 | ss->is_64_bit = (gelf_getclass(elf) == ELFCLASS64); |
1289 | ||
a1ab1285 | 1290 | ss->symtab_idx = 0; |
b68e2f91 | 1291 | ss->symtab = elf_section_by_name(elf, &ehdr, &ss->symshdr, ".symtab", |
a1ab1285 | 1292 | &ss->symtab_idx); |
b68e2f91 CS |
1293 | if (ss->symshdr.sh_type != SHT_SYMTAB) |
1294 | ss->symtab = NULL; | |
1295 | ||
1296 | ss->dynsym_idx = 0; | |
1297 | ss->dynsym = elf_section_by_name(elf, &ehdr, &ss->dynshdr, ".dynsym", | |
1298 | &ss->dynsym_idx); | |
1299 | if (ss->dynshdr.sh_type != SHT_DYNSYM) | |
1300 | ss->dynsym = NULL; | |
1301 | ||
1302 | ss->opdidx = 0; | |
1303 | ss->opdsec = elf_section_by_name(elf, &ehdr, &ss->opdshdr, ".opd", | |
1304 | &ss->opdidx); | |
1305 | if (ss->opdshdr.sh_type != SHT_PROGBITS) | |
1306 | ss->opdsec = NULL; | |
1307 | ||
ee756ef7 | 1308 | if (dso__kernel(dso) == DSO_SPACE__USER) |
99e87f7b WN |
1309 | ss->adjust_symbols = true; |
1310 | else | |
d2332098 | 1311 | ss->adjust_symbols = elf__needs_adjust_symbols(ehdr); |
b68e2f91 CS |
1312 | |
1313 | ss->name = strdup(name); | |
18425f13 | 1314 | if (!ss->name) { |
ee756ef7 | 1315 | *dso__load_errno(dso) = errno; |
b68e2f91 | 1316 | goto out_elf_end; |
18425f13 | 1317 | } |
b68e2f91 CS |
1318 | |
1319 | ss->elf = elf; | |
1320 | ss->fd = fd; | |
1321 | ss->ehdr = ehdr; | |
1322 | ss->type = type; | |
1323 | ||
1324 | return 0; | |
1325 | ||
1326 | out_elf_end: | |
1327 | elf_end(elf); | |
1328 | out_close: | |
1329 | close(fd); | |
e5f177a5 | 1330 | return -1; |
b68e2f91 CS |
1331 | } |
1332 | ||
94a830d7 AH |
1333 | static bool is_exe_text(int flags) |
1334 | { | |
1335 | return (flags & (SHF_ALLOC | SHF_EXECINSTR)) == (SHF_ALLOC | SHF_EXECINSTR); | |
1336 | } | |
1337 | ||
1338 | /* | |
1339 | * Some executable module sections like .noinstr.text might be laid out with | |
1340 | * .text so they can use the same mapping (memory address to file offset). | |
1341 | * Check if that is the case. Refer to kernel layout_sections(). Return the | |
1342 | * maximum offset. | |
1343 | */ | |
1344 | static u64 max_text_section(Elf *elf, GElf_Ehdr *ehdr) | |
1345 | { | |
1346 | Elf_Scn *sec = NULL; | |
1347 | GElf_Shdr shdr; | |
1348 | u64 offs = 0; | |
1349 | ||
1350 | /* Doesn't work for some arch */ | |
1351 | if (ehdr->e_machine == EM_PARISC || | |
1352 | ehdr->e_machine == EM_ALPHA) | |
1353 | return 0; | |
1354 | ||
1355 | /* ELF is corrupted/truncated, avoid calling elf_strptr. */ | |
1356 | if (!elf_rawdata(elf_getscn(elf, ehdr->e_shstrndx), NULL)) | |
1357 | return 0; | |
1358 | ||
1359 | while ((sec = elf_nextscn(elf, sec)) != NULL) { | |
1360 | char *sec_name; | |
1361 | ||
1362 | if (!gelf_getshdr(sec, &shdr)) | |
1363 | break; | |
1364 | ||
1365 | if (!is_exe_text(shdr.sh_flags)) | |
1366 | continue; | |
1367 | ||
1368 | /* .init and .exit sections are not placed with .text */ | |
1369 | sec_name = elf_strptr(elf, ehdr->e_shstrndx, shdr.sh_name); | |
1370 | if (!sec_name || | |
1371 | strstarts(sec_name, ".init") || | |
1372 | strstarts(sec_name, ".exit")) | |
1373 | break; | |
1374 | ||
1375 | /* Must be next to previous, assumes .text is first */ | |
1376 | if (offs && PERF_ALIGN(offs, shdr.sh_addralign ?: 1) != shdr.sh_offset) | |
1377 | break; | |
1378 | ||
1379 | offs = shdr.sh_offset + shdr.sh_size; | |
1380 | } | |
1381 | ||
1382 | return offs; | |
1383 | } | |
1384 | ||
39b12f78 AH |
1385 | /** |
1386 | * ref_reloc_sym_not_found - has kernel relocation symbol been found. | |
1387 | * @kmap: kernel maps and relocation reference symbol | |
1388 | * | |
1389 | * This function returns %true if we are dealing with the kernel maps and the | |
1390 | * relocation reference symbol has not yet been found. Otherwise %false is | |
1391 | * returned. | |
1392 | */ | |
1393 | static bool ref_reloc_sym_not_found(struct kmap *kmap) | |
1394 | { | |
1395 | return kmap && kmap->ref_reloc_sym && kmap->ref_reloc_sym->name && | |
1396 | !kmap->ref_reloc_sym->unrelocated_addr; | |
1397 | } | |
1398 | ||
1399 | /** | |
1400 | * ref_reloc - kernel relocation offset. | |
1401 | * @kmap: kernel maps and relocation reference symbol | |
1402 | * | |
1403 | * This function returns the offset of kernel addresses as determined by using | |
1404 | * the relocation reference symbol i.e. if the kernel has not been relocated | |
1405 | * then the return value is zero. | |
1406 | */ | |
1407 | static u64 ref_reloc(struct kmap *kmap) | |
1408 | { | |
1409 | if (kmap && kmap->ref_reloc_sym && | |
1410 | kmap->ref_reloc_sym->unrelocated_addr) | |
1411 | return kmap->ref_reloc_sym->addr - | |
1412 | kmap->ref_reloc_sym->unrelocated_addr; | |
1413 | return 0; | |
1414 | } | |
1415 | ||
0b3c2264 NR |
1416 | void __weak arch__sym_update(struct symbol *s __maybe_unused, |
1417 | GElf_Sym *sym __maybe_unused) { } | |
c50fc0a4 | 1418 | |
4e0d1e8b ACM |
1419 | static int dso__process_kernel_symbol(struct dso *dso, struct map *map, |
1420 | GElf_Sym *sym, GElf_Shdr *shdr, | |
79b6bb73 | 1421 | struct maps *kmaps, struct kmap *kmap, |
23106e31 | 1422 | struct dso **curr_dsop, |
4e0d1e8b | 1423 | const char *section_name, |
94a830d7 AH |
1424 | bool adjust_kernel_syms, bool kmodule, bool *remap_kernel, |
1425 | u64 max_text_sh_offset) | |
4e0d1e8b ACM |
1426 | { |
1427 | struct dso *curr_dso = *curr_dsop; | |
1428 | struct map *curr_map; | |
1429 | char dso_name[PATH_MAX]; | |
1430 | ||
1431 | /* Adjust symbol to map to file offset */ | |
1432 | if (adjust_kernel_syms) | |
1433 | sym->st_value -= shdr->sh_addr - shdr->sh_offset; | |
1434 | ||
ee756ef7 | 1435 | if (strcmp(section_name, (dso__short_name(curr_dso) + dso__short_name_len(dso))) == 0) |
4e0d1e8b ACM |
1436 | return 0; |
1437 | ||
1438 | if (strcmp(section_name, ".text") == 0) { | |
1439 | /* | |
1440 | * The initial kernel mapping is based on | |
1441 | * kallsyms and identity maps. Overwrite it to | |
1442 | * map to the kernel dso. | |
1443 | */ | |
ee756ef7 | 1444 | if (*remap_kernel && dso__kernel(dso) && !kmodule) { |
4e0d1e8b | 1445 | *remap_kernel = false; |
e6a9efce ACM |
1446 | map__set_start(map, shdr->sh_addr + ref_reloc(kmap)); |
1447 | map__set_end(map, map__start(map) + shdr->sh_size); | |
1448 | map__set_pgoff(map, shdr->sh_offset); | |
9fa688ea | 1449 | map__set_mapping_type(map, MAPPING_TYPE__DSO); |
4e0d1e8b ACM |
1450 | /* Ensure maps are correctly ordered */ |
1451 | if (kmaps) { | |
ff583dc4 | 1452 | int err; |
fe8fec10 | 1453 | struct map *tmp = map__get(map); |
ff583dc4 | 1454 | |
79b6bb73 | 1455 | maps__remove(kmaps, map); |
ff583dc4 | 1456 | err = maps__insert(kmaps, map); |
fe8fec10 | 1457 | map__put(tmp); |
ff583dc4 IR |
1458 | if (err) |
1459 | return err; | |
4e0d1e8b ACM |
1460 | } |
1461 | } | |
1462 | ||
1463 | /* | |
1464 | * The initial module mapping is based on | |
1465 | * /proc/modules mapped to offset zero. | |
1466 | * Overwrite it to map to the module dso. | |
1467 | */ | |
1468 | if (*remap_kernel && kmodule) { | |
1469 | *remap_kernel = false; | |
e6a9efce | 1470 | map__set_pgoff(map, shdr->sh_offset); |
4e0d1e8b ACM |
1471 | } |
1472 | ||
23106e31 IR |
1473 | dso__put(*curr_dsop); |
1474 | *curr_dsop = dso__get(dso); | |
4e0d1e8b ACM |
1475 | return 0; |
1476 | } | |
1477 | ||
1478 | if (!kmap) | |
1479 | return 0; | |
1480 | ||
94a830d7 AH |
1481 | /* |
1482 | * perf does not record module section addresses except for .text, but | |
1483 | * some sections can use the same mapping as .text. | |
1484 | */ | |
1485 | if (kmodule && adjust_kernel_syms && is_exe_text(shdr->sh_flags) && | |
1486 | shdr->sh_offset <= max_text_sh_offset) { | |
23106e31 IR |
1487 | dso__put(*curr_dsop); |
1488 | *curr_dsop = dso__get(dso); | |
94a830d7 AH |
1489 | return 0; |
1490 | } | |
1491 | ||
ee756ef7 | 1492 | snprintf(dso_name, sizeof(dso_name), "%s%s", dso__short_name(dso), section_name); |
4e0d1e8b | 1493 | |
79b6bb73 | 1494 | curr_map = maps__find_by_name(kmaps, dso_name); |
4e0d1e8b ACM |
1495 | if (curr_map == NULL) { |
1496 | u64 start = sym->st_value; | |
1497 | ||
1498 | if (kmodule) | |
e5116f46 | 1499 | start += map__start(map) + shdr->sh_offset; |
4e0d1e8b ACM |
1500 | |
1501 | curr_dso = dso__new(dso_name); | |
1502 | if (curr_dso == NULL) | |
1503 | return -1; | |
ee756ef7 IR |
1504 | dso__set_kernel(curr_dso, dso__kernel(dso)); |
1505 | RC_CHK_ACCESS(curr_dso)->long_name = dso__long_name(dso); | |
1506 | RC_CHK_ACCESS(curr_dso)->long_name_len = dso__long_name_len(dso); | |
1507 | dso__set_binary_type(curr_dso, dso__binary_type(dso)); | |
1508 | dso__set_adjust_symbols(curr_dso, dso__adjust_symbols(dso)); | |
4e0d1e8b | 1509 | curr_map = map__new2(start, curr_dso); |
23106e31 IR |
1510 | if (curr_map == NULL) { |
1511 | dso__put(curr_dso); | |
4e0d1e8b | 1512 | return -1; |
23106e31 | 1513 | } |
ee756ef7 | 1514 | if (dso__kernel(curr_dso)) |
a75af86b ACM |
1515 | map__kmap(curr_map)->kmaps = kmaps; |
1516 | ||
4e0d1e8b | 1517 | if (adjust_kernel_syms) { |
e6a9efce ACM |
1518 | map__set_start(curr_map, shdr->sh_addr + ref_reloc(kmap)); |
1519 | map__set_end(curr_map, map__start(curr_map) + shdr->sh_size); | |
1520 | map__set_pgoff(curr_map, shdr->sh_offset); | |
4e0d1e8b | 1521 | } else { |
9fa688ea | 1522 | map__set_mapping_type(curr_map, MAPPING_TYPE__IDENTITY); |
4e0d1e8b | 1523 | } |
ee756ef7 | 1524 | dso__set_symtab_type(curr_dso, dso__symtab_type(dso)); |
ff583dc4 IR |
1525 | if (maps__insert(kmaps, curr_map)) |
1526 | return -1; | |
5ab6d715 | 1527 | dsos__add(&maps__machine(kmaps)->dsos, curr_dso); |
4e0d1e8b | 1528 | dso__set_loaded(curr_dso); |
23106e31 | 1529 | dso__put(*curr_dsop); |
4e0d1e8b | 1530 | *curr_dsop = curr_dso; |
107ef66c | 1531 | } else { |
23106e31 IR |
1532 | dso__put(*curr_dsop); |
1533 | *curr_dsop = dso__get(map__dso(curr_map)); | |
107ef66c | 1534 | } |
23106e31 | 1535 | map__put(curr_map); |
4e0d1e8b ACM |
1536 | |
1537 | return 0; | |
1538 | } | |
1539 | ||
87704345 MH |
1540 | static int |
1541 | dso__load_sym_internal(struct dso *dso, struct map *map, struct symsrc *syms_ss, | |
1542 | struct symsrc *runtime_ss, int kmodule, int dynsym) | |
b68e2f91 | 1543 | { |
ee756ef7 | 1544 | struct kmap *kmap = dso__kernel(dso) ? map__kmap(map) : NULL; |
79b6bb73 | 1545 | struct maps *kmaps = kmap ? map__kmaps(map) : NULL; |
23106e31 | 1546 | struct dso *curr_dso = NULL; |
83952286 | 1547 | Elf_Data *symstrs, *secstrs, *secstrs_run, *secstrs_sym; |
b68e2f91 | 1548 | uint32_t nr_syms; |
b68e2f91 CS |
1549 | uint32_t idx; |
1550 | GElf_Ehdr ehdr; | |
261360b6 | 1551 | GElf_Shdr shdr; |
73cdf0c6 | 1552 | GElf_Shdr tshdr; |
b68e2f91 CS |
1553 | Elf_Data *syms, *opddata = NULL; |
1554 | GElf_Sym sym; | |
261360b6 | 1555 | Elf_Scn *sec, *sec_strndx; |
b68e2f91 CS |
1556 | Elf *elf; |
1557 | int nr = 0; | |
39b12f78 | 1558 | bool remap_kernel = false, adjust_kernel_syms = false; |
94a830d7 | 1559 | u64 max_text_sh_offset = 0; |
b68e2f91 | 1560 | |
ba92732e WN |
1561 | if (kmap && !kmaps) |
1562 | return -1; | |
1563 | ||
261360b6 CS |
1564 | elf = syms_ss->elf; |
1565 | ehdr = syms_ss->ehdr; | |
87704345 MH |
1566 | if (dynsym) { |
1567 | sec = syms_ss->dynsym; | |
1568 | shdr = syms_ss->dynshdr; | |
1569 | } else { | |
1570 | sec = syms_ss->symtab; | |
1571 | shdr = syms_ss->symshdr; | |
1572 | } | |
b68e2f91 | 1573 | |
50de1a0c | 1574 | if (elf_section_by_name(runtime_ss->elf, &runtime_ss->ehdr, &tshdr, |
26a5262d | 1575 | ".text", NULL)) { |
ee756ef7 IR |
1576 | dso__set_text_offset(dso, tshdr.sh_addr - tshdr.sh_offset); |
1577 | dso__set_text_end(dso, tshdr.sh_offset + tshdr.sh_size); | |
26a5262d | 1578 | } |
73cdf0c6 | 1579 | |
261360b6 CS |
1580 | if (runtime_ss->opdsec) |
1581 | opddata = elf_rawdata(runtime_ss->opdsec, NULL); | |
e5a1845f NK |
1582 | |
1583 | syms = elf_getdata(sec, NULL); | |
1584 | if (syms == NULL) | |
1585 | goto out_elf_end; | |
1586 | ||
1587 | sec = elf_getscn(elf, shdr.sh_link); | |
1588 | if (sec == NULL) | |
1589 | goto out_elf_end; | |
1590 | ||
1591 | symstrs = elf_getdata(sec, NULL); | |
1592 | if (symstrs == NULL) | |
1593 | goto out_elf_end; | |
1594 | ||
f247fb81 | 1595 | sec_strndx = elf_getscn(runtime_ss->elf, runtime_ss->ehdr.e_shstrndx); |
e5a1845f NK |
1596 | if (sec_strndx == NULL) |
1597 | goto out_elf_end; | |
1598 | ||
83952286 RM |
1599 | secstrs_run = elf_getdata(sec_strndx, NULL); |
1600 | if (secstrs_run == NULL) | |
1601 | goto out_elf_end; | |
1602 | ||
1603 | sec_strndx = elf_getscn(elf, ehdr.e_shstrndx); | |
1604 | if (sec_strndx == NULL) | |
1605 | goto out_elf_end; | |
1606 | ||
1607 | secstrs_sym = elf_getdata(sec_strndx, NULL); | |
1608 | if (secstrs_sym == NULL) | |
e5a1845f NK |
1609 | goto out_elf_end; |
1610 | ||
1611 | nr_syms = shdr.sh_size / shdr.sh_entsize; | |
1612 | ||
1613 | memset(&sym, 0, sizeof(sym)); | |
39b12f78 AH |
1614 | |
1615 | /* | |
1616 | * The kernel relocation symbol is needed in advance in order to adjust | |
1617 | * kernel maps correctly. | |
1618 | */ | |
1619 | if (ref_reloc_sym_not_found(kmap)) { | |
1620 | elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) { | |
1621 | const char *elf_name = elf_sym__name(&sym, symstrs); | |
1622 | ||
1623 | if (strcmp(elf_name, kmap->ref_reloc_sym->name)) | |
1624 | continue; | |
1625 | kmap->ref_reloc_sym->unrelocated_addr = sym.st_value; | |
e6a9efce | 1626 | map__set_reloc(map, kmap->ref_reloc_sym->addr - kmap->ref_reloc_sym->unrelocated_addr); |
39b12f78 AH |
1627 | break; |
1628 | } | |
1629 | } | |
1630 | ||
f0ee3b46 AH |
1631 | /* |
1632 | * Handle any relocation of vdso necessary because older kernels | |
1633 | * attempted to prelink vdso to its virtual address. | |
1634 | */ | |
73cdf0c6 | 1635 | if (dso__is_vdso(dso)) |
ee756ef7 | 1636 | map__set_reloc(map, map__start(map) - dso__text_offset(dso)); |
f0ee3b46 | 1637 | |
ee756ef7 | 1638 | dso__set_adjust_symbols(dso, runtime_ss->adjust_symbols || ref_reloc(kmap)); |
39b12f78 | 1639 | /* |
d1fd8d9e ACM |
1640 | * Initial kernel and module mappings do not map to the dso. |
1641 | * Flag the fixups. | |
39b12f78 | 1642 | */ |
ee756ef7 | 1643 | if (dso__kernel(dso)) { |
39b12f78 | 1644 | remap_kernel = true; |
ee756ef7 | 1645 | adjust_kernel_syms = dso__adjust_symbols(dso); |
39b12f78 | 1646 | } |
94a830d7 AH |
1647 | |
1648 | if (kmodule && adjust_kernel_syms) | |
1649 | max_text_sh_offset = max_text_section(runtime_ss->elf, &runtime_ss->ehdr); | |
1650 | ||
23106e31 | 1651 | curr_dso = dso__get(dso); |
e5a1845f NK |
1652 | elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) { |
1653 | struct symbol *f; | |
1654 | const char *elf_name = elf_sym__name(&sym, symstrs); | |
1655 | char *demangled = NULL; | |
1656 | int is_label = elf_sym__is_label(&sym); | |
1657 | const char *section_name; | |
261360b6 | 1658 | bool used_opd = false; |
e5a1845f | 1659 | |
3183f8ca | 1660 | if (!is_label && !elf_sym__filter(&sym)) |
e5a1845f NK |
1661 | continue; |
1662 | ||
1663 | /* Reject ARM ELF "mapping symbols": these aren't unique and | |
1664 | * don't identify functions, so will confuse the profile | |
1665 | * output: */ | |
4886f2ca VK |
1666 | if (ehdr.e_machine == EM_ARM || ehdr.e_machine == EM_AARCH64) { |
1667 | if (elf_name[0] == '$' && strchr("adtx", elf_name[1]) | |
1668 | && (elf_name[2] == '\0' || elf_name[2] == '.')) | |
e5a1845f NK |
1669 | continue; |
1670 | } | |
1671 | ||
261360b6 CS |
1672 | if (runtime_ss->opdsec && sym.st_shndx == runtime_ss->opdidx) { |
1673 | u32 offset = sym.st_value - syms_ss->opdshdr.sh_addr; | |
e5a1845f NK |
1674 | u64 *opd = opddata->d_buf + offset; |
1675 | sym.st_value = DSO__SWAP(dso, u64, *opd); | |
261360b6 CS |
1676 | sym.st_shndx = elf_addr_to_index(runtime_ss->elf, |
1677 | sym.st_value); | |
1678 | used_opd = true; | |
e5a1845f | 1679 | } |
2d86612a | 1680 | |
3843b05d NK |
1681 | /* |
1682 | * When loading symbols in a data mapping, ABS symbols (which | |
1683 | * has a value of SHN_ABS in its st_shndx) failed at | |
1684 | * elf_getscn(). And it marks the loading as a failure so | |
1685 | * already loaded symbols cannot be fixed up. | |
1686 | * | |
1687 | * I'm not sure what should be done. Just ignore them for now. | |
1688 | * - Namhyung Kim | |
1689 | */ | |
1690 | if (sym.st_shndx == SHN_ABS) | |
1691 | continue; | |
e5a1845f | 1692 | |
6833e0b8 | 1693 | sec = elf_getscn(syms_ss->elf, sym.st_shndx); |
e5a1845f NK |
1694 | if (!sec) |
1695 | goto out_elf_end; | |
1696 | ||
1697 | gelf_getshdr(sec, &shdr); | |
1698 | ||
882528d2 LY |
1699 | /* |
1700 | * If the attribute bit SHF_ALLOC is not set, the section | |
1701 | * doesn't occupy memory during process execution. | |
1702 | * E.g. ".gnu.warning.*" section is used by linker to generate | |
1703 | * warnings when calling deprecated functions, the symbols in | |
1704 | * the section aren't loaded to memory during process execution, | |
1705 | * so skip them. | |
1706 | */ | |
1707 | if (!(shdr.sh_flags & SHF_ALLOC)) | |
1708 | continue; | |
1709 | ||
83952286 RM |
1710 | secstrs = secstrs_sym; |
1711 | ||
6833e0b8 JS |
1712 | /* |
1713 | * We have to fallback to runtime when syms' section header has | |
1714 | * NOBITS set. NOBITS results in file offset (sh_offset) not | |
1715 | * being incremented. So sh_offset used below has different | |
1716 | * values for syms (invalid) and runtime (valid). | |
1717 | */ | |
1718 | if (shdr.sh_type == SHT_NOBITS) { | |
1719 | sec = elf_getscn(runtime_ss->elf, sym.st_shndx); | |
1720 | if (!sec) | |
1721 | goto out_elf_end; | |
1722 | ||
1723 | gelf_getshdr(sec, &shdr); | |
83952286 | 1724 | secstrs = secstrs_run; |
6833e0b8 JS |
1725 | } |
1726 | ||
3183f8ca | 1727 | if (is_label && !elf_sec__filter(&shdr, secstrs)) |
e5a1845f NK |
1728 | continue; |
1729 | ||
1730 | section_name = elf_sec__name(&shdr, secstrs); | |
1731 | ||
1732 | /* On ARM, symbols for thumb functions have 1 added to | |
1733 | * the symbol address as a flag - remove it */ | |
1734 | if ((ehdr.e_machine == EM_ARM) && | |
18231d79 | 1735 | (GELF_ST_TYPE(sym.st_info) == STT_FUNC) && |
e5a1845f NK |
1736 | (sym.st_value & 1)) |
1737 | --sym.st_value; | |
1738 | ||
ee756ef7 | 1739 | if (dso__kernel(dso)) { |
23106e31 IR |
1740 | if (dso__process_kernel_symbol(dso, map, &sym, &shdr, |
1741 | kmaps, kmap, &curr_dso, | |
1742 | section_name, | |
1743 | adjust_kernel_syms, | |
1744 | kmodule, | |
1745 | &remap_kernel, | |
1746 | max_text_sh_offset)) | |
4e0d1e8b | 1747 | goto out_elf_end; |
857140e8 ACM |
1748 | } else if ((used_opd && runtime_ss->adjust_symbols) || |
1749 | (!used_opd && syms_ss->adjust_symbols)) { | |
2d86612a LY |
1750 | GElf_Phdr phdr; |
1751 | ||
6f520ce1 | 1752 | if (elf_read_program_header(runtime_ss->elf, |
2d86612a | 1753 | (u64)sym.st_value, &phdr)) { |
6d518ac7 | 1754 | pr_debug4("%s: failed to find program header for " |
2d86612a LY |
1755 | "symbol: %s st_value: %#" PRIx64 "\n", |
1756 | __func__, elf_name, (u64)sym.st_value); | |
6d518ac7 IR |
1757 | pr_debug4("%s: adjusting symbol: st_value: %#" PRIx64 " " |
1758 | "sh_addr: %#" PRIx64 " sh_offset: %#" PRIx64 "\n", | |
1759 | __func__, (u64)sym.st_value, (u64)shdr.sh_addr, | |
1760 | (u64)shdr.sh_offset); | |
1761 | /* | |
1762 | * Fail to find program header, let's rollback | |
1763 | * to use shdr.sh_addr and shdr.sh_offset to | |
1764 | * calibrate symbol's file address, though this | |
1765 | * is not necessary for normal C ELF file, we | |
1766 | * still need to handle java JIT symbols in this | |
1767 | * case. | |
1768 | */ | |
1769 | sym.st_value -= shdr.sh_addr - shdr.sh_offset; | |
1770 | } else { | |
1771 | pr_debug4("%s: adjusting symbol: st_value: %#" PRIx64 " " | |
1772 | "p_vaddr: %#" PRIx64 " p_offset: %#" PRIx64 "\n", | |
1773 | __func__, (u64)sym.st_value, (u64)phdr.p_vaddr, | |
1774 | (u64)phdr.p_offset); | |
1775 | sym.st_value -= phdr.p_vaddr - phdr.p_offset; | |
2d86612a | 1776 | } |
e5a1845f | 1777 | } |
4e0d1e8b | 1778 | |
2a8d41b4 MW |
1779 | demangled = demangle_sym(dso, kmodule, elf_name); |
1780 | if (demangled != NULL) | |
1781 | elf_name = demangled; | |
cae15db7 | 1782 | |
e5a1845f | 1783 | f = symbol__new(sym.st_value, sym.st_size, |
af30bffa ACM |
1784 | GELF_ST_BIND(sym.st_info), |
1785 | GELF_ST_TYPE(sym.st_info), elf_name); | |
e5a1845f NK |
1786 | free(demangled); |
1787 | if (!f) | |
1788 | goto out_elf_end; | |
1789 | ||
0b3c2264 NR |
1790 | arch__sym_update(f, &sym); |
1791 | ||
ee756ef7 | 1792 | __symbols__insert(dso__symbols(curr_dso), f, dso__kernel(dso)); |
be39db9f | 1793 | nr++; |
e5a1845f | 1794 | } |
23106e31 | 1795 | dso__put(curr_dso); |
e5a1845f NK |
1796 | |
1797 | /* | |
1798 | * For misannotated, zeroed, ASM function sizes. | |
1799 | */ | |
1800 | if (nr > 0) { | |
ee756ef7 IR |
1801 | symbols__fixup_end(dso__symbols(dso), false); |
1802 | symbols__fixup_duplicate(dso__symbols(dso)); | |
e5a1845f NK |
1803 | if (kmap) { |
1804 | /* | |
1805 | * We need to fixup this here too because we create new | |
1806 | * maps here, for things like vsyscall sections. | |
1807 | */ | |
79b6bb73 | 1808 | maps__fixup_end(kmaps); |
e5a1845f NK |
1809 | } |
1810 | } | |
23106e31 | 1811 | return nr; |
e5a1845f | 1812 | out_elf_end: |
23106e31 IR |
1813 | dso__put(curr_dso); |
1814 | return -1; | |
e5a1845f NK |
1815 | } |
1816 | ||
87704345 MH |
1817 | int dso__load_sym(struct dso *dso, struct map *map, struct symsrc *syms_ss, |
1818 | struct symsrc *runtime_ss, int kmodule) | |
1819 | { | |
1820 | int nr = 0; | |
1821 | int err = -1; | |
1822 | ||
ee756ef7 IR |
1823 | dso__set_symtab_type(dso, syms_ss->type); |
1824 | dso__set_is_64_bit(dso, syms_ss->is_64_bit); | |
1825 | dso__set_rel(dso, syms_ss->ehdr.e_type == ET_REL); | |
87704345 MH |
1826 | |
1827 | /* | |
1828 | * Modules may already have symbols from kallsyms, but those symbols | |
1829 | * have the wrong values for the dso maps, so remove them. | |
1830 | */ | |
1831 | if (kmodule && syms_ss->symtab) | |
ee756ef7 | 1832 | symbols__delete(dso__symbols(dso)); |
87704345 MH |
1833 | |
1834 | if (!syms_ss->symtab) { | |
1835 | /* | |
1836 | * If the vmlinux is stripped, fail so we will fall back | |
1837 | * to using kallsyms. The vmlinux runtime symbols aren't | |
1838 | * of much use. | |
1839 | */ | |
ee756ef7 | 1840 | if (dso__kernel(dso)) |
87704345 MH |
1841 | return err; |
1842 | } else { | |
1843 | err = dso__load_sym_internal(dso, map, syms_ss, runtime_ss, | |
1844 | kmodule, 0); | |
1845 | if (err < 0) | |
1846 | return err; | |
1847 | nr = err; | |
1848 | } | |
1849 | ||
1850 | if (syms_ss->dynsym) { | |
1851 | err = dso__load_sym_internal(dso, map, syms_ss, runtime_ss, | |
1852 | kmodule, 1); | |
1853 | if (err < 0) | |
1854 | return err; | |
1855 | err += nr; | |
1856 | } | |
1857 | ||
1858 | return err; | |
1859 | } | |
1860 | ||
8e0cf965 AH |
1861 | static int elf_read_maps(Elf *elf, bool exe, mapfn_t mapfn, void *data) |
1862 | { | |
1863 | GElf_Phdr phdr; | |
1864 | size_t i, phdrnum; | |
1865 | int err; | |
1866 | u64 sz; | |
1867 | ||
1868 | if (elf_getphdrnum(elf, &phdrnum)) | |
1869 | return -1; | |
1870 | ||
1871 | for (i = 0; i < phdrnum; i++) { | |
1872 | if (gelf_getphdr(elf, i, &phdr) == NULL) | |
1873 | return -1; | |
1874 | if (phdr.p_type != PT_LOAD) | |
1875 | continue; | |
1876 | if (exe) { | |
1877 | if (!(phdr.p_flags & PF_X)) | |
1878 | continue; | |
1879 | } else { | |
1880 | if (!(phdr.p_flags & PF_R)) | |
1881 | continue; | |
1882 | } | |
1883 | sz = min(phdr.p_memsz, phdr.p_filesz); | |
1884 | if (!sz) | |
1885 | continue; | |
1886 | err = mapfn(phdr.p_vaddr, sz, phdr.p_offset, data); | |
1887 | if (err) | |
1888 | return err; | |
1889 | } | |
1890 | return 0; | |
1891 | } | |
1892 | ||
1893 | int file__read_maps(int fd, bool exe, mapfn_t mapfn, void *data, | |
1894 | bool *is_64_bit) | |
1895 | { | |
1896 | int err; | |
1897 | Elf *elf; | |
1898 | ||
1899 | elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL); | |
1900 | if (elf == NULL) | |
1901 | return -1; | |
1902 | ||
1903 | if (is_64_bit) | |
1904 | *is_64_bit = (gelf_getclass(elf) == ELFCLASS64); | |
1905 | ||
1906 | err = elf_read_maps(elf, exe, mapfn, data); | |
1907 | ||
1908 | elf_end(elf); | |
1909 | return err; | |
1910 | } | |
1911 | ||
2b5b8bb2 AH |
1912 | enum dso_type dso__type_fd(int fd) |
1913 | { | |
1914 | enum dso_type dso_type = DSO__TYPE_UNKNOWN; | |
1915 | GElf_Ehdr ehdr; | |
1916 | Elf_Kind ek; | |
1917 | Elf *elf; | |
1918 | ||
1919 | elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL); | |
1920 | if (elf == NULL) | |
1921 | goto out; | |
1922 | ||
1923 | ek = elf_kind(elf); | |
1924 | if (ek != ELF_K_ELF) | |
1925 | goto out_end; | |
1926 | ||
1927 | if (gelf_getclass(elf) == ELFCLASS64) { | |
1928 | dso_type = DSO__TYPE_64BIT; | |
1929 | goto out_end; | |
1930 | } | |
1931 | ||
1932 | if (gelf_getehdr(elf, &ehdr) == NULL) | |
1933 | goto out_end; | |
1934 | ||
1935 | if (ehdr.e_machine == EM_X86_64) | |
1936 | dso_type = DSO__TYPE_X32BIT; | |
1937 | else | |
1938 | dso_type = DSO__TYPE_32BIT; | |
1939 | out_end: | |
1940 | elf_end(elf); | |
1941 | out: | |
1942 | return dso_type; | |
1943 | } | |
1944 | ||
afba19d9 AH |
1945 | static int copy_bytes(int from, off_t from_offs, int to, off_t to_offs, u64 len) |
1946 | { | |
1947 | ssize_t r; | |
1948 | size_t n; | |
1949 | int err = -1; | |
1950 | char *buf = malloc(page_size); | |
1951 | ||
1952 | if (buf == NULL) | |
1953 | return -1; | |
1954 | ||
1955 | if (lseek(to, to_offs, SEEK_SET) != to_offs) | |
1956 | goto out; | |
1957 | ||
1958 | if (lseek(from, from_offs, SEEK_SET) != from_offs) | |
1959 | goto out; | |
1960 | ||
1961 | while (len) { | |
1962 | n = page_size; | |
1963 | if (len < n) | |
1964 | n = len; | |
1965 | /* Use read because mmap won't work on proc files */ | |
1966 | r = read(from, buf, n); | |
1967 | if (r < 0) | |
1968 | goto out; | |
1969 | if (!r) | |
1970 | break; | |
1971 | n = r; | |
1972 | r = write(to, buf, n); | |
1973 | if (r < 0) | |
1974 | goto out; | |
1975 | if ((size_t)r != n) | |
1976 | goto out; | |
1977 | len -= n; | |
1978 | } | |
1979 | ||
1980 | err = 0; | |
1981 | out: | |
1982 | free(buf); | |
1983 | return err; | |
1984 | } | |
1985 | ||
1986 | struct kcore { | |
1987 | int fd; | |
1988 | int elfclass; | |
1989 | Elf *elf; | |
1990 | GElf_Ehdr ehdr; | |
1991 | }; | |
1992 | ||
1993 | static int kcore__open(struct kcore *kcore, const char *filename) | |
1994 | { | |
1995 | GElf_Ehdr *ehdr; | |
1996 | ||
1997 | kcore->fd = open(filename, O_RDONLY); | |
1998 | if (kcore->fd == -1) | |
1999 | return -1; | |
2000 | ||
2001 | kcore->elf = elf_begin(kcore->fd, ELF_C_READ, NULL); | |
2002 | if (!kcore->elf) | |
2003 | goto out_close; | |
2004 | ||
2005 | kcore->elfclass = gelf_getclass(kcore->elf); | |
2006 | if (kcore->elfclass == ELFCLASSNONE) | |
2007 | goto out_end; | |
2008 | ||
2009 | ehdr = gelf_getehdr(kcore->elf, &kcore->ehdr); | |
2010 | if (!ehdr) | |
2011 | goto out_end; | |
2012 | ||
2013 | return 0; | |
2014 | ||
2015 | out_end: | |
2016 | elf_end(kcore->elf); | |
2017 | out_close: | |
2018 | close(kcore->fd); | |
2019 | return -1; | |
2020 | } | |
2021 | ||
2022 | static int kcore__init(struct kcore *kcore, char *filename, int elfclass, | |
2023 | bool temp) | |
2024 | { | |
afba19d9 AH |
2025 | kcore->elfclass = elfclass; |
2026 | ||
2027 | if (temp) | |
2028 | kcore->fd = mkstemp(filename); | |
2029 | else | |
2030 | kcore->fd = open(filename, O_WRONLY | O_CREAT | O_EXCL, 0400); | |
2031 | if (kcore->fd == -1) | |
2032 | return -1; | |
2033 | ||
2034 | kcore->elf = elf_begin(kcore->fd, ELF_C_WRITE, NULL); | |
2035 | if (!kcore->elf) | |
2036 | goto out_close; | |
2037 | ||
2038 | if (!gelf_newehdr(kcore->elf, elfclass)) | |
2039 | goto out_end; | |
2040 | ||
b5cabbcb | 2041 | memset(&kcore->ehdr, 0, sizeof(GElf_Ehdr)); |
afba19d9 AH |
2042 | |
2043 | return 0; | |
2044 | ||
2045 | out_end: | |
2046 | elf_end(kcore->elf); | |
2047 | out_close: | |
2048 | close(kcore->fd); | |
2049 | unlink(filename); | |
2050 | return -1; | |
2051 | } | |
2052 | ||
2053 | static void kcore__close(struct kcore *kcore) | |
2054 | { | |
2055 | elf_end(kcore->elf); | |
2056 | close(kcore->fd); | |
2057 | } | |
2058 | ||
2059 | static int kcore__copy_hdr(struct kcore *from, struct kcore *to, size_t count) | |
2060 | { | |
2061 | GElf_Ehdr *ehdr = &to->ehdr; | |
2062 | GElf_Ehdr *kehdr = &from->ehdr; | |
2063 | ||
2064 | memcpy(ehdr->e_ident, kehdr->e_ident, EI_NIDENT); | |
2065 | ehdr->e_type = kehdr->e_type; | |
2066 | ehdr->e_machine = kehdr->e_machine; | |
2067 | ehdr->e_version = kehdr->e_version; | |
2068 | ehdr->e_entry = 0; | |
2069 | ehdr->e_shoff = 0; | |
2070 | ehdr->e_flags = kehdr->e_flags; | |
2071 | ehdr->e_phnum = count; | |
2072 | ehdr->e_shentsize = 0; | |
2073 | ehdr->e_shnum = 0; | |
2074 | ehdr->e_shstrndx = 0; | |
2075 | ||
2076 | if (from->elfclass == ELFCLASS32) { | |
2077 | ehdr->e_phoff = sizeof(Elf32_Ehdr); | |
2078 | ehdr->e_ehsize = sizeof(Elf32_Ehdr); | |
2079 | ehdr->e_phentsize = sizeof(Elf32_Phdr); | |
2080 | } else { | |
2081 | ehdr->e_phoff = sizeof(Elf64_Ehdr); | |
2082 | ehdr->e_ehsize = sizeof(Elf64_Ehdr); | |
2083 | ehdr->e_phentsize = sizeof(Elf64_Phdr); | |
2084 | } | |
2085 | ||
2086 | if (!gelf_update_ehdr(to->elf, ehdr)) | |
2087 | return -1; | |
2088 | ||
2089 | if (!gelf_newphdr(to->elf, count)) | |
2090 | return -1; | |
2091 | ||
2092 | return 0; | |
2093 | } | |
2094 | ||
2095 | static int kcore__add_phdr(struct kcore *kcore, int idx, off_t offset, | |
2096 | u64 addr, u64 len) | |
2097 | { | |
b5cabbcb AH |
2098 | GElf_Phdr phdr = { |
2099 | .p_type = PT_LOAD, | |
2100 | .p_flags = PF_R | PF_W | PF_X, | |
2101 | .p_offset = offset, | |
2102 | .p_vaddr = addr, | |
2103 | .p_paddr = 0, | |
2104 | .p_filesz = len, | |
2105 | .p_memsz = len, | |
2106 | .p_align = page_size, | |
2107 | }; | |
2108 | ||
2109 | if (!gelf_update_phdr(kcore->elf, idx, &phdr)) | |
afba19d9 AH |
2110 | return -1; |
2111 | ||
2112 | return 0; | |
2113 | } | |
2114 | ||
2115 | static off_t kcore__write(struct kcore *kcore) | |
2116 | { | |
2117 | return elf_update(kcore->elf, ELF_C_WRITE); | |
2118 | } | |
2119 | ||
fc1b691d AH |
2120 | struct phdr_data { |
2121 | off_t offset; | |
15acef6c | 2122 | off_t rel; |
fc1b691d AH |
2123 | u64 addr; |
2124 | u64 len; | |
f6838209 | 2125 | struct list_head node; |
22916fdb | 2126 | struct phdr_data *remaps; |
fc1b691d AH |
2127 | }; |
2128 | ||
a1a3a062 AH |
2129 | struct sym_data { |
2130 | u64 addr; | |
2131 | struct list_head node; | |
2132 | }; | |
2133 | ||
fc1b691d AH |
2134 | struct kcore_copy_info { |
2135 | u64 stext; | |
2136 | u64 etext; | |
2137 | u64 first_symbol; | |
2138 | u64 last_symbol; | |
2139 | u64 first_module; | |
61f82e3f | 2140 | u64 first_module_symbol; |
fc1b691d | 2141 | u64 last_module_symbol; |
6e97957d | 2142 | size_t phnum; |
f6838209 | 2143 | struct list_head phdrs; |
a1a3a062 | 2144 | struct list_head syms; |
fc1b691d AH |
2145 | }; |
2146 | ||
15acef6c AH |
2147 | #define kcore_copy__for_each_phdr(k, p) \ |
2148 | list_for_each_entry((p), &(k)->phdrs, node) | |
2149 | ||
b4503cdb AH |
2150 | static struct phdr_data *phdr_data__new(u64 addr, u64 len, off_t offset) |
2151 | { | |
2152 | struct phdr_data *p = zalloc(sizeof(*p)); | |
2153 | ||
2154 | if (p) { | |
2155 | p->addr = addr; | |
2156 | p->len = len; | |
2157 | p->offset = offset; | |
2158 | } | |
2159 | ||
2160 | return p; | |
2161 | } | |
2162 | ||
2163 | static struct phdr_data *kcore_copy_info__addnew(struct kcore_copy_info *kci, | |
2164 | u64 addr, u64 len, | |
2165 | off_t offset) | |
2166 | { | |
2167 | struct phdr_data *p = phdr_data__new(addr, len, offset); | |
2168 | ||
2169 | if (p) | |
2170 | list_add_tail(&p->node, &kci->phdrs); | |
2171 | ||
2172 | return p; | |
2173 | } | |
2174 | ||
2175 | static void kcore_copy__free_phdrs(struct kcore_copy_info *kci) | |
2176 | { | |
2177 | struct phdr_data *p, *tmp; | |
2178 | ||
2179 | list_for_each_entry_safe(p, tmp, &kci->phdrs, node) { | |
e56fbc9d | 2180 | list_del_init(&p->node); |
b4503cdb AH |
2181 | free(p); |
2182 | } | |
2183 | } | |
2184 | ||
a1a3a062 AH |
2185 | static struct sym_data *kcore_copy__new_sym(struct kcore_copy_info *kci, |
2186 | u64 addr) | |
2187 | { | |
2188 | struct sym_data *s = zalloc(sizeof(*s)); | |
2189 | ||
2190 | if (s) { | |
2191 | s->addr = addr; | |
2192 | list_add_tail(&s->node, &kci->syms); | |
2193 | } | |
2194 | ||
2195 | return s; | |
2196 | } | |
2197 | ||
2198 | static void kcore_copy__free_syms(struct kcore_copy_info *kci) | |
2199 | { | |
2200 | struct sym_data *s, *tmp; | |
2201 | ||
2202 | list_for_each_entry_safe(s, tmp, &kci->syms, node) { | |
e56fbc9d | 2203 | list_del_init(&s->node); |
a1a3a062 AH |
2204 | free(s); |
2205 | } | |
2206 | } | |
2207 | ||
fc1b691d AH |
2208 | static int kcore_copy__process_kallsyms(void *arg, const char *name, char type, |
2209 | u64 start) | |
2210 | { | |
2211 | struct kcore_copy_info *kci = arg; | |
2212 | ||
e85e0e0c | 2213 | if (!kallsyms__is_function(type)) |
fc1b691d AH |
2214 | return 0; |
2215 | ||
2216 | if (strchr(name, '[')) { | |
61f82e3f AH |
2217 | if (!kci->first_module_symbol || start < kci->first_module_symbol) |
2218 | kci->first_module_symbol = start; | |
fc1b691d AH |
2219 | if (start > kci->last_module_symbol) |
2220 | kci->last_module_symbol = start; | |
2221 | return 0; | |
2222 | } | |
2223 | ||
2224 | if (!kci->first_symbol || start < kci->first_symbol) | |
2225 | kci->first_symbol = start; | |
2226 | ||
2227 | if (!kci->last_symbol || start > kci->last_symbol) | |
2228 | kci->last_symbol = start; | |
2229 | ||
2230 | if (!strcmp(name, "_stext")) { | |
2231 | kci->stext = start; | |
2232 | return 0; | |
2233 | } | |
2234 | ||
2235 | if (!strcmp(name, "_etext")) { | |
2236 | kci->etext = start; | |
2237 | return 0; | |
2238 | } | |
2239 | ||
a1a3a062 AH |
2240 | if (is_entry_trampoline(name) && !kcore_copy__new_sym(kci, start)) |
2241 | return -1; | |
2242 | ||
fc1b691d AH |
2243 | return 0; |
2244 | } | |
2245 | ||
2246 | static int kcore_copy__parse_kallsyms(struct kcore_copy_info *kci, | |
2247 | const char *dir) | |
2248 | { | |
2249 | char kallsyms_filename[PATH_MAX]; | |
2250 | ||
2251 | scnprintf(kallsyms_filename, PATH_MAX, "%s/kallsyms", dir); | |
2252 | ||
2253 | if (symbol__restricted_filename(kallsyms_filename, "/proc/kallsyms")) | |
2254 | return -1; | |
2255 | ||
2256 | if (kallsyms__parse(kallsyms_filename, kci, | |
2257 | kcore_copy__process_kallsyms) < 0) | |
2258 | return -1; | |
2259 | ||
2260 | return 0; | |
2261 | } | |
2262 | ||
2263 | static int kcore_copy__process_modules(void *arg, | |
2264 | const char *name __maybe_unused, | |
9ad4652b | 2265 | u64 start, u64 size __maybe_unused) |
fc1b691d AH |
2266 | { |
2267 | struct kcore_copy_info *kci = arg; | |
2268 | ||
2269 | if (!kci->first_module || start < kci->first_module) | |
2270 | kci->first_module = start; | |
2271 | ||
2272 | return 0; | |
2273 | } | |
2274 | ||
2275 | static int kcore_copy__parse_modules(struct kcore_copy_info *kci, | |
2276 | const char *dir) | |
2277 | { | |
2278 | char modules_filename[PATH_MAX]; | |
2279 | ||
2280 | scnprintf(modules_filename, PATH_MAX, "%s/modules", dir); | |
2281 | ||
2282 | if (symbol__restricted_filename(modules_filename, "/proc/modules")) | |
2283 | return -1; | |
2284 | ||
2285 | if (modules__parse(modules_filename, kci, | |
2286 | kcore_copy__process_modules) < 0) | |
2287 | return -1; | |
2288 | ||
2289 | return 0; | |
2290 | } | |
2291 | ||
b4503cdb AH |
2292 | static int kcore_copy__map(struct kcore_copy_info *kci, u64 start, u64 end, |
2293 | u64 pgoff, u64 s, u64 e) | |
fc1b691d | 2294 | { |
b4503cdb AH |
2295 | u64 len, offset; |
2296 | ||
2297 | if (s < start || s >= end) | |
2298 | return 0; | |
fc1b691d | 2299 | |
b4503cdb AH |
2300 | offset = (s - start) + pgoff; |
2301 | len = e < end ? e - s : end - s; | |
2302 | ||
2303 | return kcore_copy_info__addnew(kci, s, len, offset) ? 0 : -1; | |
fc1b691d AH |
2304 | } |
2305 | ||
2306 | static int kcore_copy__read_map(u64 start, u64 len, u64 pgoff, void *data) | |
2307 | { | |
2308 | struct kcore_copy_info *kci = data; | |
2309 | u64 end = start + len; | |
a1a3a062 | 2310 | struct sym_data *sdat; |
fc1b691d | 2311 | |
b4503cdb AH |
2312 | if (kcore_copy__map(kci, start, end, pgoff, kci->stext, kci->etext)) |
2313 | return -1; | |
fc1b691d | 2314 | |
b4503cdb AH |
2315 | if (kcore_copy__map(kci, start, end, pgoff, kci->first_module, |
2316 | kci->last_module_symbol)) | |
2317 | return -1; | |
fc1b691d | 2318 | |
a1a3a062 AH |
2319 | list_for_each_entry(sdat, &kci->syms, node) { |
2320 | u64 s = round_down(sdat->addr, page_size); | |
2321 | ||
2322 | if (kcore_copy__map(kci, start, end, pgoff, s, s + len)) | |
2323 | return -1; | |
2324 | } | |
2325 | ||
fc1b691d AH |
2326 | return 0; |
2327 | } | |
2328 | ||
2329 | static int kcore_copy__read_maps(struct kcore_copy_info *kci, Elf *elf) | |
2330 | { | |
2331 | if (elf_read_maps(elf, true, kcore_copy__read_map, kci) < 0) | |
2332 | return -1; | |
2333 | ||
2334 | return 0; | |
2335 | } | |
2336 | ||
22916fdb AH |
2337 | static void kcore_copy__find_remaps(struct kcore_copy_info *kci) |
2338 | { | |
2339 | struct phdr_data *p, *k = NULL; | |
2340 | u64 kend; | |
2341 | ||
2342 | if (!kci->stext) | |
2343 | return; | |
2344 | ||
2345 | /* Find phdr that corresponds to the kernel map (contains stext) */ | |
2346 | kcore_copy__for_each_phdr(kci, p) { | |
2347 | u64 pend = p->addr + p->len - 1; | |
2348 | ||
2349 | if (p->addr <= kci->stext && pend >= kci->stext) { | |
2350 | k = p; | |
2351 | break; | |
2352 | } | |
2353 | } | |
2354 | ||
2355 | if (!k) | |
2356 | return; | |
2357 | ||
2358 | kend = k->offset + k->len; | |
2359 | ||
2360 | /* Find phdrs that remap the kernel */ | |
2361 | kcore_copy__for_each_phdr(kci, p) { | |
2362 | u64 pend = p->offset + p->len; | |
2363 | ||
2364 | if (p == k) | |
2365 | continue; | |
2366 | ||
2367 | if (p->offset >= k->offset && pend <= kend) | |
2368 | p->remaps = k; | |
2369 | } | |
2370 | } | |
2371 | ||
15acef6c AH |
2372 | static void kcore_copy__layout(struct kcore_copy_info *kci) |
2373 | { | |
2374 | struct phdr_data *p; | |
2375 | off_t rel = 0; | |
2376 | ||
22916fdb AH |
2377 | kcore_copy__find_remaps(kci); |
2378 | ||
15acef6c | 2379 | kcore_copy__for_each_phdr(kci, p) { |
22916fdb AH |
2380 | if (!p->remaps) { |
2381 | p->rel = rel; | |
2382 | rel += p->len; | |
2383 | } | |
15acef6c AH |
2384 | kci->phnum += 1; |
2385 | } | |
22916fdb AH |
2386 | |
2387 | kcore_copy__for_each_phdr(kci, p) { | |
2388 | struct phdr_data *k = p->remaps; | |
2389 | ||
2390 | if (k) | |
2391 | p->rel = p->offset - k->offset + k->rel; | |
2392 | } | |
15acef6c AH |
2393 | } |
2394 | ||
fc1b691d AH |
2395 | static int kcore_copy__calc_maps(struct kcore_copy_info *kci, const char *dir, |
2396 | Elf *elf) | |
2397 | { | |
2398 | if (kcore_copy__parse_kallsyms(kci, dir)) | |
2399 | return -1; | |
2400 | ||
2401 | if (kcore_copy__parse_modules(kci, dir)) | |
2402 | return -1; | |
2403 | ||
2404 | if (kci->stext) | |
2405 | kci->stext = round_down(kci->stext, page_size); | |
2406 | else | |
2407 | kci->stext = round_down(kci->first_symbol, page_size); | |
2408 | ||
2409 | if (kci->etext) { | |
2410 | kci->etext = round_up(kci->etext, page_size); | |
2411 | } else if (kci->last_symbol) { | |
2412 | kci->etext = round_up(kci->last_symbol, page_size); | |
2413 | kci->etext += page_size; | |
2414 | } | |
2415 | ||
61f82e3f AH |
2416 | if (kci->first_module_symbol && |
2417 | (!kci->first_module || kci->first_module_symbol < kci->first_module)) | |
2418 | kci->first_module = kci->first_module_symbol; | |
2419 | ||
fc1b691d AH |
2420 | kci->first_module = round_down(kci->first_module, page_size); |
2421 | ||
2422 | if (kci->last_module_symbol) { | |
2423 | kci->last_module_symbol = round_up(kci->last_module_symbol, | |
2424 | page_size); | |
2425 | kci->last_module_symbol += page_size; | |
2426 | } | |
2427 | ||
2428 | if (!kci->stext || !kci->etext) | |
2429 | return -1; | |
2430 | ||
2431 | if (kci->first_module && !kci->last_module_symbol) | |
2432 | return -1; | |
2433 | ||
15acef6c AH |
2434 | if (kcore_copy__read_maps(kci, elf)) |
2435 | return -1; | |
2436 | ||
2437 | kcore_copy__layout(kci); | |
2438 | ||
2439 | return 0; | |
fc1b691d AH |
2440 | } |
2441 | ||
2442 | static int kcore_copy__copy_file(const char *from_dir, const char *to_dir, | |
2443 | const char *name) | |
2444 | { | |
2445 | char from_filename[PATH_MAX]; | |
2446 | char to_filename[PATH_MAX]; | |
2447 | ||
2448 | scnprintf(from_filename, PATH_MAX, "%s/%s", from_dir, name); | |
2449 | scnprintf(to_filename, PATH_MAX, "%s/%s", to_dir, name); | |
2450 | ||
2451 | return copyfile_mode(from_filename, to_filename, 0400); | |
2452 | } | |
2453 | ||
2454 | static int kcore_copy__unlink(const char *dir, const char *name) | |
2455 | { | |
2456 | char filename[PATH_MAX]; | |
2457 | ||
2458 | scnprintf(filename, PATH_MAX, "%s/%s", dir, name); | |
2459 | ||
2460 | return unlink(filename); | |
2461 | } | |
2462 | ||
2463 | static int kcore_copy__compare_fds(int from, int to) | |
2464 | { | |
2465 | char *buf_from; | |
2466 | char *buf_to; | |
2467 | ssize_t ret; | |
2468 | size_t len; | |
2469 | int err = -1; | |
2470 | ||
2471 | buf_from = malloc(page_size); | |
2472 | buf_to = malloc(page_size); | |
2473 | if (!buf_from || !buf_to) | |
2474 | goto out; | |
2475 | ||
2476 | while (1) { | |
2477 | /* Use read because mmap won't work on proc files */ | |
2478 | ret = read(from, buf_from, page_size); | |
2479 | if (ret < 0) | |
2480 | goto out; | |
2481 | ||
2482 | if (!ret) | |
2483 | break; | |
2484 | ||
2485 | len = ret; | |
2486 | ||
2487 | if (readn(to, buf_to, len) != (int)len) | |
2488 | goto out; | |
2489 | ||
2490 | if (memcmp(buf_from, buf_to, len)) | |
2491 | goto out; | |
2492 | } | |
2493 | ||
2494 | err = 0; | |
2495 | out: | |
2496 | free(buf_to); | |
2497 | free(buf_from); | |
2498 | return err; | |
2499 | } | |
2500 | ||
2501 | static int kcore_copy__compare_files(const char *from_filename, | |
2502 | const char *to_filename) | |
2503 | { | |
2504 | int from, to, err = -1; | |
2505 | ||
2506 | from = open(from_filename, O_RDONLY); | |
2507 | if (from < 0) | |
2508 | return -1; | |
2509 | ||
2510 | to = open(to_filename, O_RDONLY); | |
2511 | if (to < 0) | |
2512 | goto out_close_from; | |
2513 | ||
2514 | err = kcore_copy__compare_fds(from, to); | |
2515 | ||
2516 | close(to); | |
2517 | out_close_from: | |
2518 | close(from); | |
2519 | return err; | |
2520 | } | |
2521 | ||
2522 | static int kcore_copy__compare_file(const char *from_dir, const char *to_dir, | |
2523 | const char *name) | |
2524 | { | |
2525 | char from_filename[PATH_MAX]; | |
2526 | char to_filename[PATH_MAX]; | |
2527 | ||
2528 | scnprintf(from_filename, PATH_MAX, "%s/%s", from_dir, name); | |
2529 | scnprintf(to_filename, PATH_MAX, "%s/%s", to_dir, name); | |
2530 | ||
2531 | return kcore_copy__compare_files(from_filename, to_filename); | |
2532 | } | |
2533 | ||
2534 | /** | |
2535 | * kcore_copy - copy kallsyms, modules and kcore from one directory to another. | |
2536 | * @from_dir: from directory | |
2537 | * @to_dir: to directory | |
2538 | * | |
2539 | * This function copies kallsyms, modules and kcore files from one directory to | |
2540 | * another. kallsyms and modules are copied entirely. Only code segments are | |
2541 | * copied from kcore. It is assumed that two segments suffice: one for the | |
2542 | * kernel proper and one for all the modules. The code segments are determined | |
2543 | * from kallsyms and modules files. The kernel map starts at _stext or the | |
2544 | * lowest function symbol, and ends at _etext or the highest function symbol. | |
2545 | * The module map starts at the lowest module address and ends at the highest | |
2546 | * module symbol. Start addresses are rounded down to the nearest page. End | |
2547 | * addresses are rounded up to the nearest page. An extra page is added to the | |
2548 | * highest kernel symbol and highest module symbol to, hopefully, encompass that | |
2549 | * symbol too. Because it contains only code sections, the resulting kcore is | |
2550 | * unusual. One significant peculiarity is that the mapping (start -> pgoff) | |
2551 | * is not the same for the kernel map and the modules map. That happens because | |
2552 | * the data is copied adjacently whereas the original kcore has gaps. Finally, | |
5b427df2 AH |
2553 | * kallsyms file is compared with its copy to check that modules have not been |
2554 | * loaded or unloaded while the copies were taking place. | |
fc1b691d AH |
2555 | * |
2556 | * Return: %0 on success, %-1 on failure. | |
2557 | */ | |
2558 | int kcore_copy(const char *from_dir, const char *to_dir) | |
2559 | { | |
2560 | struct kcore kcore; | |
2561 | struct kcore extract; | |
fc1b691d | 2562 | int idx = 0, err = -1; |
d2c95980 | 2563 | off_t offset, sz; |
fc1b691d AH |
2564 | struct kcore_copy_info kci = { .stext = 0, }; |
2565 | char kcore_filename[PATH_MAX]; | |
2566 | char extract_filename[PATH_MAX]; | |
d2c95980 | 2567 | struct phdr_data *p; |
fc1b691d | 2568 | |
f6838209 | 2569 | INIT_LIST_HEAD(&kci.phdrs); |
a1a3a062 | 2570 | INIT_LIST_HEAD(&kci.syms); |
f6838209 | 2571 | |
fc1b691d AH |
2572 | if (kcore_copy__copy_file(from_dir, to_dir, "kallsyms")) |
2573 | return -1; | |
2574 | ||
2575 | if (kcore_copy__copy_file(from_dir, to_dir, "modules")) | |
2576 | goto out_unlink_kallsyms; | |
2577 | ||
2578 | scnprintf(kcore_filename, PATH_MAX, "%s/kcore", from_dir); | |
2579 | scnprintf(extract_filename, PATH_MAX, "%s/kcore", to_dir); | |
2580 | ||
2581 | if (kcore__open(&kcore, kcore_filename)) | |
2582 | goto out_unlink_modules; | |
2583 | ||
2584 | if (kcore_copy__calc_maps(&kci, from_dir, kcore.elf)) | |
2585 | goto out_kcore_close; | |
2586 | ||
2587 | if (kcore__init(&extract, extract_filename, kcore.elfclass, false)) | |
2588 | goto out_kcore_close; | |
2589 | ||
6e97957d | 2590 | if (kcore__copy_hdr(&kcore, &extract, kci.phnum)) |
fc1b691d AH |
2591 | goto out_extract_close; |
2592 | ||
c9dd1d89 AH |
2593 | offset = gelf_fsize(extract.elf, ELF_T_EHDR, 1, EV_CURRENT) + |
2594 | gelf_fsize(extract.elf, ELF_T_PHDR, kci.phnum, EV_CURRENT); | |
2595 | offset = round_up(offset, page_size); | |
2596 | ||
d2c95980 AH |
2597 | kcore_copy__for_each_phdr(&kci, p) { |
2598 | off_t offs = p->rel + offset; | |
fc1b691d | 2599 | |
d2c95980 | 2600 | if (kcore__add_phdr(&extract, idx++, offs, p->addr, p->len)) |
fc1b691d AH |
2601 | goto out_extract_close; |
2602 | } | |
2603 | ||
2604 | sz = kcore__write(&extract); | |
2605 | if (sz < 0 || sz > offset) | |
2606 | goto out_extract_close; | |
2607 | ||
d2c95980 AH |
2608 | kcore_copy__for_each_phdr(&kci, p) { |
2609 | off_t offs = p->rel + offset; | |
fc1b691d | 2610 | |
22916fdb AH |
2611 | if (p->remaps) |
2612 | continue; | |
d2c95980 AH |
2613 | if (copy_bytes(kcore.fd, p->offset, extract.fd, offs, p->len)) |
2614 | goto out_extract_close; | |
2615 | } | |
fc1b691d | 2616 | |
fc1b691d AH |
2617 | if (kcore_copy__compare_file(from_dir, to_dir, "kallsyms")) |
2618 | goto out_extract_close; | |
2619 | ||
2620 | err = 0; | |
2621 | ||
2622 | out_extract_close: | |
2623 | kcore__close(&extract); | |
2624 | if (err) | |
2625 | unlink(extract_filename); | |
2626 | out_kcore_close: | |
2627 | kcore__close(&kcore); | |
2628 | out_unlink_modules: | |
2629 | if (err) | |
2630 | kcore_copy__unlink(to_dir, "modules"); | |
2631 | out_unlink_kallsyms: | |
2632 | if (err) | |
2633 | kcore_copy__unlink(to_dir, "kallsyms"); | |
2634 | ||
b4503cdb | 2635 | kcore_copy__free_phdrs(&kci); |
a1a3a062 | 2636 | kcore_copy__free_syms(&kci); |
b4503cdb | 2637 | |
fc1b691d AH |
2638 | return err; |
2639 | } | |
2640 | ||
afba19d9 AH |
2641 | int kcore_extract__create(struct kcore_extract *kce) |
2642 | { | |
2643 | struct kcore kcore; | |
2644 | struct kcore extract; | |
2645 | size_t count = 1; | |
2646 | int idx = 0, err = -1; | |
2647 | off_t offset = page_size, sz; | |
2648 | ||
2649 | if (kcore__open(&kcore, kce->kcore_filename)) | |
2650 | return -1; | |
2651 | ||
2652 | strcpy(kce->extract_filename, PERF_KCORE_EXTRACT); | |
2653 | if (kcore__init(&extract, kce->extract_filename, kcore.elfclass, true)) | |
2654 | goto out_kcore_close; | |
2655 | ||
2656 | if (kcore__copy_hdr(&kcore, &extract, count)) | |
2657 | goto out_extract_close; | |
2658 | ||
2659 | if (kcore__add_phdr(&extract, idx, offset, kce->addr, kce->len)) | |
2660 | goto out_extract_close; | |
2661 | ||
2662 | sz = kcore__write(&extract); | |
2663 | if (sz < 0 || sz > offset) | |
2664 | goto out_extract_close; | |
2665 | ||
2666 | if (copy_bytes(kcore.fd, kce->offs, extract.fd, offset, kce->len)) | |
2667 | goto out_extract_close; | |
2668 | ||
2669 | err = 0; | |
2670 | ||
2671 | out_extract_close: | |
2672 | kcore__close(&extract); | |
2673 | if (err) | |
2674 | unlink(kce->extract_filename); | |
2675 | out_kcore_close: | |
2676 | kcore__close(&kcore); | |
2677 | ||
2678 | return err; | |
2679 | } | |
2680 | ||
2681 | void kcore_extract__delete(struct kcore_extract *kce) | |
2682 | { | |
2683 | unlink(kce->extract_filename); | |
2684 | } | |
2685 | ||
1c1a3a47 | 2686 | #ifdef HAVE_GELF_GETNOTE_SUPPORT |
5a5e3d3c RB |
2687 | |
2688 | static void sdt_adjust_loc(struct sdt_note *tmp, GElf_Addr base_off) | |
2689 | { | |
2690 | if (!base_off) | |
2691 | return; | |
2692 | ||
2693 | if (tmp->bit32) | |
2694 | tmp->addr.a32[SDT_NOTE_IDX_LOC] = | |
2695 | tmp->addr.a32[SDT_NOTE_IDX_LOC] + base_off - | |
2696 | tmp->addr.a32[SDT_NOTE_IDX_BASE]; | |
2697 | else | |
2698 | tmp->addr.a64[SDT_NOTE_IDX_LOC] = | |
2699 | tmp->addr.a64[SDT_NOTE_IDX_LOC] + base_off - | |
2700 | tmp->addr.a64[SDT_NOTE_IDX_BASE]; | |
2701 | } | |
2702 | ||
2703 | static void sdt_adjust_refctr(struct sdt_note *tmp, GElf_Addr base_addr, | |
2704 | GElf_Addr base_off) | |
2705 | { | |
2706 | if (!base_off) | |
2707 | return; | |
2708 | ||
2709 | if (tmp->bit32 && tmp->addr.a32[SDT_NOTE_IDX_REFCTR]) | |
2710 | tmp->addr.a32[SDT_NOTE_IDX_REFCTR] -= (base_addr - base_off); | |
2711 | else if (tmp->addr.a64[SDT_NOTE_IDX_REFCTR]) | |
2712 | tmp->addr.a64[SDT_NOTE_IDX_REFCTR] -= (base_addr - base_off); | |
2713 | } | |
2714 | ||
060fa0c7 HK |
2715 | /** |
2716 | * populate_sdt_note : Parse raw data and identify SDT note | |
2717 | * @elf: elf of the opened file | |
2718 | * @data: raw data of a section with description offset applied | |
2719 | * @len: note description size | |
2720 | * @type: type of the note | |
2721 | * @sdt_notes: List to add the SDT note | |
2722 | * | |
2723 | * Responsible for parsing the @data in section .note.stapsdt in @elf and | |
2724 | * if its an SDT note, it appends to @sdt_notes list. | |
2725 | */ | |
2726 | static int populate_sdt_note(Elf **elf, const char *data, size_t len, | |
2727 | struct list_head *sdt_notes) | |
2728 | { | |
be88184b | 2729 | const char *provider, *name, *args; |
060fa0c7 HK |
2730 | struct sdt_note *tmp = NULL; |
2731 | GElf_Ehdr ehdr; | |
060fa0c7 HK |
2732 | GElf_Shdr shdr; |
2733 | int ret = -EINVAL; | |
2734 | ||
2735 | union { | |
2736 | Elf64_Addr a64[NR_ADDR]; | |
2737 | Elf32_Addr a32[NR_ADDR]; | |
2738 | } buf; | |
2739 | ||
2740 | Elf_Data dst = { | |
2741 | .d_buf = &buf, .d_type = ELF_T_ADDR, .d_version = EV_CURRENT, | |
2742 | .d_size = gelf_fsize((*elf), ELF_T_ADDR, NR_ADDR, EV_CURRENT), | |
2743 | .d_off = 0, .d_align = 0 | |
2744 | }; | |
2745 | Elf_Data src = { | |
2746 | .d_buf = (void *) data, .d_type = ELF_T_ADDR, | |
2747 | .d_version = EV_CURRENT, .d_size = dst.d_size, .d_off = 0, | |
2748 | .d_align = 0 | |
2749 | }; | |
2750 | ||
2751 | tmp = (struct sdt_note *)calloc(1, sizeof(struct sdt_note)); | |
2752 | if (!tmp) { | |
2753 | ret = -ENOMEM; | |
2754 | goto out_err; | |
2755 | } | |
2756 | ||
2757 | INIT_LIST_HEAD(&tmp->note_list); | |
2758 | ||
2759 | if (len < dst.d_size + 3) | |
2760 | goto out_free_note; | |
2761 | ||
2762 | /* Translation from file representation to memory representation */ | |
2763 | if (gelf_xlatetom(*elf, &dst, &src, | |
2764 | elf_getident(*elf, NULL)[EI_DATA]) == NULL) { | |
2765 | pr_err("gelf_xlatetom : %s\n", elf_errmsg(-1)); | |
2766 | goto out_free_note; | |
2767 | } | |
2768 | ||
2769 | /* Populate the fields of sdt_note */ | |
2770 | provider = data + dst.d_size; | |
2771 | ||
2772 | name = (const char *)memchr(provider, '\0', data + len - provider); | |
2773 | if (name++ == NULL) | |
2774 | goto out_free_note; | |
2775 | ||
2776 | tmp->provider = strdup(provider); | |
2777 | if (!tmp->provider) { | |
2778 | ret = -ENOMEM; | |
2779 | goto out_free_note; | |
2780 | } | |
2781 | tmp->name = strdup(name); | |
2782 | if (!tmp->name) { | |
2783 | ret = -ENOMEM; | |
2784 | goto out_free_prov; | |
2785 | } | |
2786 | ||
be88184b AB |
2787 | args = memchr(name, '\0', data + len - name); |
2788 | ||
2789 | /* | |
2790 | * There is no argument if: | |
2791 | * - We reached the end of the note; | |
2792 | * - There is not enough room to hold a potential string; | |
2793 | * - The argument string is empty or just contains ':'. | |
2794 | */ | |
2795 | if (args == NULL || data + len - args < 2 || | |
2796 | args[1] == ':' || args[1] == '\0') | |
2797 | tmp->args = NULL; | |
2798 | else { | |
2799 | tmp->args = strdup(++args); | |
2800 | if (!tmp->args) { | |
2801 | ret = -ENOMEM; | |
2802 | goto out_free_name; | |
2803 | } | |
2804 | } | |
2805 | ||
060fa0c7 HK |
2806 | if (gelf_getclass(*elf) == ELFCLASS32) { |
2807 | memcpy(&tmp->addr, &buf, 3 * sizeof(Elf32_Addr)); | |
2808 | tmp->bit32 = true; | |
2809 | } else { | |
2810 | memcpy(&tmp->addr, &buf, 3 * sizeof(Elf64_Addr)); | |
2811 | tmp->bit32 = false; | |
2812 | } | |
2813 | ||
2814 | if (!gelf_getehdr(*elf, &ehdr)) { | |
2815 | pr_debug("%s : cannot get elf header.\n", __func__); | |
2816 | ret = -EBADF; | |
be88184b | 2817 | goto out_free_args; |
060fa0c7 HK |
2818 | } |
2819 | ||
2820 | /* Adjust the prelink effect : | |
2821 | * Find out the .stapsdt.base section. | |
2822 | * This scn will help us to handle prelinking (if present). | |
2823 | * Compare the retrieved file offset of the base section with the | |
2824 | * base address in the description of the SDT note. If its different, | |
2825 | * then accordingly, adjust the note location. | |
2826 | */ | |
5a5e3d3c RB |
2827 | if (elf_section_by_name(*elf, &ehdr, &shdr, SDT_BASE_SCN, NULL)) |
2828 | sdt_adjust_loc(tmp, shdr.sh_offset); | |
2829 | ||
2830 | /* Adjust reference counter offset */ | |
2831 | if (elf_section_by_name(*elf, &ehdr, &shdr, SDT_PROBES_SCN, NULL)) | |
2832 | sdt_adjust_refctr(tmp, shdr.sh_addr, shdr.sh_offset); | |
060fa0c7 HK |
2833 | |
2834 | list_add_tail(&tmp->note_list, sdt_notes); | |
2835 | return 0; | |
2836 | ||
be88184b | 2837 | out_free_args: |
d8f9da24 | 2838 | zfree(&tmp->args); |
060fa0c7 | 2839 | out_free_name: |
d8f9da24 | 2840 | zfree(&tmp->name); |
060fa0c7 | 2841 | out_free_prov: |
d8f9da24 | 2842 | zfree(&tmp->provider); |
060fa0c7 HK |
2843 | out_free_note: |
2844 | free(tmp); | |
2845 | out_err: | |
2846 | return ret; | |
2847 | } | |
2848 | ||
2849 | /** | |
2850 | * construct_sdt_notes_list : constructs a list of SDT notes | |
2851 | * @elf : elf to look into | |
2852 | * @sdt_notes : empty list_head | |
2853 | * | |
2854 | * Scans the sections in 'elf' for the section | |
2855 | * .note.stapsdt. It, then calls populate_sdt_note to find | |
2856 | * out the SDT events and populates the 'sdt_notes'. | |
2857 | */ | |
2858 | static int construct_sdt_notes_list(Elf *elf, struct list_head *sdt_notes) | |
2859 | { | |
2860 | GElf_Ehdr ehdr; | |
2861 | Elf_Scn *scn = NULL; | |
2862 | Elf_Data *data; | |
2863 | GElf_Shdr shdr; | |
2864 | size_t shstrndx, next; | |
2865 | GElf_Nhdr nhdr; | |
2866 | size_t name_off, desc_off, offset; | |
2867 | int ret = 0; | |
2868 | ||
2869 | if (gelf_getehdr(elf, &ehdr) == NULL) { | |
2870 | ret = -EBADF; | |
2871 | goto out_ret; | |
2872 | } | |
2873 | if (elf_getshdrstrndx(elf, &shstrndx) != 0) { | |
2874 | ret = -EBADF; | |
2875 | goto out_ret; | |
2876 | } | |
2877 | ||
2878 | /* Look for the required section */ | |
2879 | scn = elf_section_by_name(elf, &ehdr, &shdr, SDT_NOTE_SCN, NULL); | |
2880 | if (!scn) { | |
2881 | ret = -ENOENT; | |
2882 | goto out_ret; | |
2883 | } | |
2884 | ||
2885 | if ((shdr.sh_type != SHT_NOTE) || (shdr.sh_flags & SHF_ALLOC)) { | |
2886 | ret = -ENOENT; | |
2887 | goto out_ret; | |
2888 | } | |
2889 | ||
2890 | data = elf_getdata(scn, NULL); | |
2891 | ||
2892 | /* Get the SDT notes */ | |
2893 | for (offset = 0; (next = gelf_getnote(data, offset, &nhdr, &name_off, | |
2894 | &desc_off)) > 0; offset = next) { | |
2895 | if (nhdr.n_namesz == sizeof(SDT_NOTE_NAME) && | |
2896 | !memcmp(data->d_buf + name_off, SDT_NOTE_NAME, | |
2897 | sizeof(SDT_NOTE_NAME))) { | |
2898 | /* Check the type of the note */ | |
2899 | if (nhdr.n_type != SDT_NOTE_TYPE) | |
2900 | goto out_ret; | |
2901 | ||
2902 | ret = populate_sdt_note(&elf, ((data->d_buf) + desc_off), | |
2903 | nhdr.n_descsz, sdt_notes); | |
2904 | if (ret < 0) | |
2905 | goto out_ret; | |
2906 | } | |
2907 | } | |
2908 | if (list_empty(sdt_notes)) | |
2909 | ret = -ENOENT; | |
2910 | ||
2911 | out_ret: | |
2912 | return ret; | |
2913 | } | |
2914 | ||
2915 | /** | |
2916 | * get_sdt_note_list : Wrapper to construct a list of sdt notes | |
2917 | * @head : empty list_head | |
2918 | * @target : file to find SDT notes from | |
2919 | * | |
2920 | * This opens the file, initializes | |
2921 | * the ELF and then calls construct_sdt_notes_list. | |
2922 | */ | |
2923 | int get_sdt_note_list(struct list_head *head, const char *target) | |
2924 | { | |
2925 | Elf *elf; | |
2926 | int fd, ret; | |
2927 | ||
2928 | fd = open(target, O_RDONLY); | |
2929 | if (fd < 0) | |
2930 | return -EBADF; | |
2931 | ||
2932 | elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL); | |
2933 | if (!elf) { | |
2934 | ret = -EBADF; | |
2935 | goto out_close; | |
2936 | } | |
2937 | ret = construct_sdt_notes_list(elf, head); | |
2938 | elf_end(elf); | |
2939 | out_close: | |
2940 | close(fd); | |
2941 | return ret; | |
2942 | } | |
2943 | ||
2944 | /** | |
2945 | * cleanup_sdt_note_list : free the sdt notes' list | |
2946 | * @sdt_notes: sdt notes' list | |
2947 | * | |
2948 | * Free up the SDT notes in @sdt_notes. | |
2949 | * Returns the number of SDT notes free'd. | |
2950 | */ | |
2951 | int cleanup_sdt_note_list(struct list_head *sdt_notes) | |
2952 | { | |
2953 | struct sdt_note *tmp, *pos; | |
2954 | int nr_free = 0; | |
2955 | ||
2956 | list_for_each_entry_safe(pos, tmp, sdt_notes, note_list) { | |
e56fbc9d | 2957 | list_del_init(&pos->note_list); |
69c9ffed | 2958 | zfree(&pos->args); |
d8f9da24 ACM |
2959 | zfree(&pos->name); |
2960 | zfree(&pos->provider); | |
060fa0c7 HK |
2961 | free(pos); |
2962 | nr_free++; | |
2963 | } | |
2964 | return nr_free; | |
2965 | } | |
2966 | ||
2967 | /** | |
2968 | * sdt_notes__get_count: Counts the number of sdt events | |
2969 | * @start: list_head to sdt_notes list | |
2970 | * | |
2971 | * Returns the number of SDT notes in a list | |
2972 | */ | |
2973 | int sdt_notes__get_count(struct list_head *start) | |
2974 | { | |
2975 | struct sdt_note *sdt_ptr; | |
2976 | int count = 0; | |
2977 | ||
2978 | list_for_each_entry(sdt_ptr, start, note_list) | |
2979 | count++; | |
2980 | return count; | |
2981 | } | |
1c1a3a47 | 2982 | #endif |
060fa0c7 | 2983 | |
e5a1845f NK |
2984 | void symbol__elf_init(void) |
2985 | { | |
2986 | elf_version(EV_CURRENT); | |
2987 | } |