fusl/src/ldso/dynlink.c - Issue 1689833004: [fusl] Update fusl

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Issue 1689833004: [fusl] Update fusl (Closed) Base URL: git@github.com:domokit/mojo.git@master

Patch Set: remove stray space Created 4 years, 10 months ago

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1 #define _GNU_SOURCE

2 #include <stdio.h>

3 #include <stdlib.h>

4 #include <stdarg.h>

5 #include <stddef.h>

6 #include <string.h>

7 #include <unistd.h>

8 #include <stdint.h>

9 #include <elf.h>

10 #include <sys/mman.h>

11 #include <limits.h>

12 #include <fcntl.h>

13 #include <sys/stat.h>

14 #include <errno.h>

15 #include <link.h>

16 #include <setjmp.h>

17 #include <pthread.h>

18 #include <ctype.h>

19 #include <dlfcn.h>

20 #include "pthread_impl.h"

21 #include "libc.h"

22 #include "dynlink.h"

23

24 static void error(const char *, ...);

25

26 #ifdef SHARED

27

28 #define MAXP2(a,b) (-(-(a)&-(b)))

29 #define ALIGN(x,y) ((x)+(y)-1 & -(y))

30

31 struct debug {

32 int ver;

33 void *head;

34 void (*bp)(void);

35 int state;

36 void *base;

37 };

38

39 struct td_index {

40 size_t args[2];

41 struct td_index *next;

42 };

43

44 struct dso {

45 #if DL_FDPIC

46 struct fdpic_loadmap *loadmap;

47 #else

48 unsigned char *base;

49 #endif

50 char *name;

51 size_t *dynv;

52 struct dso next, prev;

53

54 Phdr *phdr;

55 int phnum;

56 size_t phentsize;

57 int refcnt;

58 Sym *syms;

59 uint32_t *hashtab;

60 uint32_t *ghashtab;

61 int16_t *versym;

62 char *strings;

63 unsigned char *map;

64 size_t map_len;

65 dev_t dev;

66 ino_t ino;

67 signed char global;

68 char relocated;

69 char constructed;

70 char kernel_mapped;

71 struct dso *deps, needed_by;

72 char rpath_orig, rpath;

73 struct tls_module tls;

74 size_t tls_id;

75 size_t relro_start, relro_end;

76 void **new_dtv;

77 unsigned char *new_tls;

78 volatile int new_dtv_idx, new_tls_idx;

79 struct td_index *td_index;

80 struct dso *fini_next;

81 char *shortname;

82 #if DL_FDPIC

83 unsigned char *base;

84 #else

85 struct fdpic_loadmap *loadmap;

86 #endif

87 struct funcdesc {

88 void *addr;

89 size_t *got;

90 } *funcdescs;

91 size_t *got;

92 char buf[];

93 };

94

95 struct symdef {

96 Sym *sym;

97 struct dso *dso;

98 };

99

100 int __init_tp(void *);

101 void __init_libc(char *, char );

102 void __copy_tls(unsigned char );

103

104 __attribute__((__visibility__("hidden")))

105 const char *__libc_get_version(void);

106

107 static struct builtin_tls {

108 char c;

109 struct pthread pt;

110 void *space[16];

111 } builtin_tls[1];

112 #define MIN_TLS_ALIGN offsetof(struct builtin_tls, pt)

113

114 #define ADDEND_LIMIT 4096

115 static size_t saved_addends, apply_addends_to;

116

117 static struct dso ldso;

118 static struct dso head, tail, *fini_head;

119 static char env_path, sys_path;

120 static unsigned long long gencnt;

121 static int runtime;

122 static int ldd_mode;

123 static int ldso_fail;

124 static int noload;

125 static jmp_buf *rtld_fail;

126 static pthread_rwlock_t lock;

127 static struct debug debug;

128 static struct tls_module *tls_tail;

129 static size_t tls_cnt, tls_offset, tls_align = MIN_TLS_ALIGN;

130 static size_t static_tls_cnt;

131 static pthread_mutex_t init_fini_lock = { ._m_type = PTHREAD_MUTEX_RECURSIVE };

132 static struct fdpic_loadmap *app_loadmap;

133 static struct fdpic_dummy_loadmap app_dummy_loadmap;

134

135 struct debug *_dl_debug_addr = &debug;

136

137 __attribute__((__visibility__("hidden")))

138 void (const __init_array_start)(void)=0, (const __fini_array_start)(void)=0;

139

140 __attribute__((__visibility__("hidden")))

141 extern void (const __init_array_end)(void), (const __fini_array_end)(void);

142

143 weak_alias(__init_array_start, __init_array_end);

144 weak_alias(__fini_array_start, __fini_array_end);

145

146 static int dl_strcmp(const char l, const char r)

147 {

148 for (; l==r && *l; l++, r++);

149 return (unsigned char )l - (unsigned char )r;

150 }

151 #define strcmp(l,r) dl_strcmp(l,r)

152

153 /* Compute load address for a virtual address in a given dso. */

154 #if DL_FDPIC

155 static void laddr(const struct dso p, size_t v)

156 {

157 size_t j=0;

158 if (!p->loadmap) return p->base + v;

159 for (j=0; v-p->loadmap->segs[j].p_vaddr >= p->loadmap->segs[j].p_memsz; j++);

160 return (void *)(v - p->loadmap->segs[j].p_vaddr + p->loadmap->segs[j].ad dr);

161 }

162 #define fpaddr(p, v) ((void (*)())&(struct funcdesc){ \

163 laddr(p, v), (p)->got })

164 #else

165 #define laddr(p, v) (void *)((p)->base + (v))

166 #define fpaddr(p, v) ((void (*)())laddr(p, v))

167 #endif

168

169 static void decode_vec(size_t v, size_t a, size_t cnt)

170 {

171 size_t i;

172 for (i=0; i<cnt; i++) a[i] = 0;

173 for (; v[0]; v+=2) if (v[0]-1<cnt-1) {

174 a[0] \|= 1UL<<v[0];

175 a[v[0]] = v[1];

176 }

177 }

178

179 static int search_vec(size_t v, size_t r, size_t key)

180 {

181 for (; v[0]!=key; v+=2)

182 if (!v[0]) return 0;

183 *r = v[1];

184 return 1;

185 }

186

187 static uint32_t sysv_hash(const char *s0)

188 {

189 const unsigned char s = (void )s0;

190 uint_fast32_t h = 0;

191 while (*s) {

192 h = 16h + s++;

193 h ^= h>>24 & 0xf0;

194 }

195 return h & 0xfffffff;

196 }

197

198 static uint32_t gnu_hash(const char *s0)

199 {

200 const unsigned char s = (void )s0;

201 uint_fast32_t h = 5381;

202 for (; *s; s++)

203 h += h32 + s;

204 return h;

205 }

206

207 static Sym sysv_lookup(const char s, uint32_t h, struct dso *dso)

208 {

209 size_t i;

210 Sym *syms = dso->syms;

211 uint32_t *hashtab = dso->hashtab;

212 char *strings = dso->strings;

213 for (i=hashtab[2+h%hashtab[0]]; i; i=hashtab[2+hashtab[0]+i]) {

214 if ((!dso->versym \|\| dso->versym[i] >= 0)

215 && (!strcmp(s, strings+syms[i].st_name)))

216 return syms+i;

217 }

218 return 0;

219 }

220

221 static Sym gnu_lookup(uint32_t h1, uint32_t hashtab, struct dso dso, const ch ar s)

222 {

223 uint32_t nbuckets = hashtab[0];

224 uint32_t buckets = hashtab + 4 + hashtab[2](sizeof(size_t)/4);

225 uint32_t i = buckets[h1 % nbuckets];

226

227 if (!i) return 0;

228

229 uint32_t *hashval = buckets + nbuckets + (i - hashtab[1]);

230

231 for (h1 \|= 1; ; i++) {

232 uint32_t h2 = *hashval++;

233 if ((h1 == (h2\|1)) && (!dso->versym \|\| dso->versym[i] >= 0)

234 && !strcmp(s, dso->strings + dso->syms[i].st_name))

235 return dso->syms+i;

236 if (h2 & 1) break;

237 }

238

239 return 0;

240 }

241

242 static Sym gnu_lookup_filtered(uint32_t h1, uint32_t hashtab, struct dso dso, const char s, uint32_t fofs, size_t fmask)

243 {

244 const size_t bloomwords = (const void )(hashtab+4);

245 size_t f = bloomwords[fofs & (hashtab[2]-1)];

246 if (!(f & fmask)) return 0;

247

248 f >>= (h1 >> hashtab[3]) % (8 * sizeof f);

249 if (!(f & 1)) return 0;

250

251 return gnu_lookup(h1, hashtab, dso, s);

252 }

253

254 #define OK_TYPES (1<<STT_NOTYPE \| 1<<STT_OBJECT \| 1<<STT_FUNC \| 1<<STT_COMMON \| 1<<STT_TLS)

255 #define OK_BINDS (1<<STB_GLOBAL \| 1<<STB_WEAK \| 1<<STB_GNU_UNIQUE)

256

257 #ifndef ARCH_SYM_REJECT_UND

258 #define ARCH_SYM_REJECT_UND(s) 0

259 #endif

260

261 static struct symdef find_sym(struct dso dso, const char s, int need_def)

262 {

263 uint32_t h = 0, gh, gho, *ght;

264 size_t ghm = 0;

265 struct symdef def = {0};

266 for (; dso; dso=dso->next) {

267 Sym *sym;

268 if (!dso->global) continue;

269 if ((ght = dso->ghashtab)) {

270 if (!ghm) {

271 gh = gnu_hash(s);

272 int maskbits = 8 * sizeof ghm;

273 gho = gh / maskbits;

274 ghm = 1ul << gh % maskbits;

275 }

276 sym = gnu_lookup_filtered(gh, ght, dso, s, gho, ghm);

277 } else {

278 if (!h) h = sysv_hash(s);

279 sym = sysv_lookup(s, h, dso);

280 }

281 if (!sym) continue;

282 if (!sym->st_shndx)

283 if (need_def \|\| (sym->st_info&0xf) == STT_TLS

284 \|\| ARCH_SYM_REJECT_UND(sym))

285 continue;

286 if (!sym->st_value)

287 if ((sym->st_info&0xf) != STT_TLS)

288 continue;

289 if (!(1<<(sym->st_info&0xf) & OK_TYPES)) continue;

290 if (!(1<<(sym->st_info>>4) & OK_BINDS)) continue;

291

292 if (def.sym && sym->st_info>>4 == STB_WEAK) continue;

293 def.sym = sym;

294 def.dso = dso;

295 if (sym->st_info>>4 == STB_GLOBAL) break;

296 }

297 return def;

298 }

299

300 __attribute__((__visibility__("hidden")))

301 ptrdiff_t __tlsdesc_static(), __tlsdesc_dynamic();

302

303 static void do_relocs(struct dso dso, size_t rel, size_t rel_size, size_t stri de)

304 {

305 unsigned char *base = dso->base;

306 Sym *syms = dso->syms;

307 char *strings = dso->strings;

308 Sym *sym;

309 const char *name;

310 void *ctx;

311 int type;

312 int sym_index;

313 struct symdef def;

314 size_t *reloc_addr;

315 size_t sym_val;

316 size_t tls_val;

317 size_t addend;

318 int skip_relative = 0, reuse_addends = 0, save_slot = 0;

319

320 if (dso == &ldso) {

321 /* Only ldso's REL table needs addend saving/reuse. */

322 if (rel == apply_addends_to)

323 reuse_addends = 1;

324 skip_relative = 1;

325 }

326

327 for (; rel_size; rel+=stride, rel_size-=stride*sizeof(size_t)) {

328 if (skip_relative && IS_RELATIVE(rel[1], dso->syms)) continue;

329 type = R_TYPE(rel[1]);

330 if (type == REL_NONE) continue;

331 sym_index = R_SYM(rel[1]);

332 reloc_addr = laddr(dso, rel[0]);

333 if (sym_index) {

334 sym = syms + sym_index;

335 name = strings + sym->st_name;

336 ctx = type==REL_COPY ? head->next : head;

337 def = (sym->st_info&0xf) == STT_SECTION

338 ? (struct symdef){ .dso = dso, .sym = sym }

339 : find_sym(ctx, name, type==REL_PLT);

340 if (!def.sym && (sym->st_shndx != SHN_UNDEF

341 \|\| sym->st_info>>4 != STB_WEAK)) {

342 error("Error relocating %s: %s: symbol not found ",

343 dso->name, name);

344 if (runtime) longjmp(*rtld_fail, 1);

345 continue;

346 }

347 } else {

348 sym = 0;

349 def.sym = 0;

350 def.dso = dso;

351 }

352

353 if (stride > 2) {

354 addend = rel[2];

355 } else if (type==REL_GOT \|\| type==REL_PLT\|\| type==REL_COPY) {

356 addend = 0;

357 } else if (reuse_addends) {

358 /* Save original addend in stage 2 where the dso

359 * chain consists of just ldso; otherwise read back

360 * saved addend since the inline one was clobbered. */

361 if (head==&ldso)

362 saved_addends[save_slot] = *reloc_addr;

363 addend = saved_addends[save_slot++];

364 } else {

365 addend = *reloc_addr;

366 }

367

368 sym_val = def.sym ? (size_t)laddr(def.dso, def.sym->st_value) : 0;

369 tls_val = def.sym ? def.sym->st_value : 0;

370

371 switch(type) {

372 case REL_NONE:

373 break;

374 case REL_OFFSET:

375 addend -= (size_t)reloc_addr;

376 case REL_SYMBOLIC:

377 case REL_GOT:

378 case REL_PLT:

379 *reloc_addr = sym_val + addend;

380 break;

381 case REL_RELATIVE:

382 *reloc_addr = (size_t)base + addend;

383 break;

384 case REL_SYM_OR_REL:

385 if (sym) *reloc_addr = sym_val + addend;

386 else *reloc_addr = (size_t)base + addend;

387 break;

388 case REL_COPY:

389 memcpy(reloc_addr, (void *)sym_val, sym->st_size);

390 break;

391 case REL_OFFSET32:

392 (uint32_t )reloc_addr = sym_val + addend

393 - (size_t)reloc_addr;

394 break;

395 case REL_FUNCDESC:

396 *reloc_addr = def.sym ? (size_t)(def.dso->funcdescs

397 + (def.sym - def.dso->syms)) : 0;

398 break;

399 case REL_FUNCDESC_VAL:

400 if ((sym->st_info&0xf) == STT_SECTION) *reloc_addr += sy m_val;

401 else *reloc_addr = sym_val;

402 reloc_addr[1] = def.sym ? (size_t)def.dso->got : 0;

403 break;

404 case REL_DTPMOD:

405 *reloc_addr = def.dso->tls_id;

406 break;

407 case REL_DTPOFF:

408 *reloc_addr = tls_val + addend - DTP_OFFSET;

409 break;

410 #ifdef TLS_ABOVE_TP

411 case REL_TPOFF:

412 *reloc_addr = tls_val + def.dso->tls.offset + TPOFF_K + addend;

413 break;

414 #else

415 case REL_TPOFF:

416 *reloc_addr = tls_val - def.dso->tls.offset + addend;

417 break;

418 case REL_TPOFF_NEG:

419 *reloc_addr = def.dso->tls.offset - tls_val + addend;

420 break;

421 #endif

422 case REL_TLSDESC:

423 if (stride<3) addend = reloc_addr[1];

424 if (runtime && def.dso->tls_id >= static_tls_cnt) {

425 struct td_index new = malloc(sizeof new);

426 if (!new) {

427 error(

428 "Error relocating %s: cannot allocate TL SDESC for %s",

429 dso->name, sym ? name : "(local)" );

430 longjmp(*rtld_fail, 1);

431 }

432 new->next = dso->td_index;

433 dso->td_index = new;

434 new->args[0] = def.dso->tls_id;

435 new->args[1] = tls_val + addend;

436 reloc_addr[0] = (size_t)__tlsdesc_dynamic;

437 reloc_addr[1] = (size_t)new;

438 } else {

439 reloc_addr[0] = (size_t)__tlsdesc_static;

440 #ifdef TLS_ABOVE_TP

441 reloc_addr[1] = tls_val + def.dso->tls.offset

442 + TPOFF_K + addend;

443 #else

444 reloc_addr[1] = tls_val - def.dso->tls.offset

445 + addend;

446 #endif

447 }

448 break;

449 default:

450 error("Error relocating %s: unsupported relocation type %d",

451 dso->name, type);

452 if (runtime) longjmp(*rtld_fail, 1);

453 continue;

454 }

455 }

456 }

457

458 /* A huge hack: to make up for the wastefulness of shared libraries

459 * needing at least a page of dirty memory even if they have no global

460 * data, we reclaim the gaps at the beginning and end of writable maps

461 * and "donate" them to the heap by setting up minimal malloc

462 * structures and then freeing them. */

463

464 static void reclaim(struct dso *dso, size_t start, size_t end)

465 {

466 size_t a, z;

467 if (start >= dso->relro_start && start < dso->relro_end) start = dso->re lro_end;

468 if (end >= dso->relro_start && end < dso->relro_end) end = dso->relr o_start;

469 start = start + 6sizeof(size_t)-1 & -4sizeof(size_t);

470 end = (end & -4sizeof(size_t)) - 2sizeof(size_t);

471 if (start>end \|\| end-start < 4*sizeof(size_t)) return;

472 a = laddr(dso, start);

473 z = laddr(dso, end);

474 a[-2] = 1;

475 a[-1] = z[0] = end-start + 2*sizeof(size_t) \| 1;

476 z[1] = 1;

477 free(a);

478 }

479

480 static void reclaim_gaps(struct dso *dso)

481 {

482 Phdr *ph = dso->phdr;

483 size_t phcnt = dso->phnum;

484

485 if (DL_FDPIC) return; // FIXME

486 for (; phcnt--; ph=(void )((char )ph+dso->phentsize)) {

487 if (ph->p_type!=PT_LOAD) continue;

488 if ((ph->p_flags&(PF_R\|PF_W))!=(PF_R\|PF_W)) continue;

489 reclaim(dso, ph->p_vaddr & -PAGE_SIZE, ph->p_vaddr);

490 reclaim(dso, ph->p_vaddr+ph->p_memsz,

491 ph->p_vaddr+ph->p_memsz+PAGE_SIZE-1 & -PAGE_SIZE);

492 }

493 }

494

495 static void mmap_fixed(void p, size_t n, int prot, int flags, int fd, off_t of f)

496 {

497 static int no_map_fixed;

498 char *q;

499 if (!no_map_fixed) {

500 q = mmap(p, n, prot, flags\|MAP_FIXED, fd, off);

501 if (!DL_NOMMU_SUPPORT \|\| q != MAP_FAILED \|\| errno != EINVAL)

502 return q;

503 no_map_fixed = 1;

504 }

505 /* Fallbacks for MAP_FIXED failure on NOMMU kernels. */

506 if (flags & MAP_ANONYMOUS) {

507 memset(p, 0, n);

508 return p;

509 }

510 ssize_t r;

511 if (lseek(fd, off, SEEK_SET) < 0) return MAP_FAILED;

512 for (q=p; n; q+=r, off+=r, n-=r) {

513 r = read(fd, q, n);

514 if (r < 0 && errno != EINTR) return MAP_FAILED;

515 if (!r) {

516 memset(q, 0, n);

517 break;

518 }

519 }

520 return p;

521 }

522

523 static void unmap_library(struct dso *dso)

524 {

525 if (dso->loadmap) {

526 size_t i;

527 for (i=0; i<dso->loadmap->nsegs; i++) {

528 if (!dso->loadmap->segs[i].p_memsz)

529 continue;

530 munmap((void *)dso->loadmap->segs[i].addr,

531 dso->loadmap->segs[i].p_memsz);

532 }

533 free(dso->loadmap);

534 } else if (dso->map && dso->map_len) {

535 munmap(dso->map, dso->map_len);

536 }

537 }

538

539 static void map_library(int fd, struct dso dso)

540 {

541 Ehdr buf[(896+sizeof(Ehdr))/sizeof(Ehdr)];

542 void *allocated_buf=0;

543 size_t phsize;

544 size_t addr_min=SIZE_MAX, addr_max=0, map_len;

545 size_t this_min, this_max;

546 size_t nsegs = 0;

547 off_t off_start;

548 Ehdr *eh;

549 Phdr ph, ph0;

550 unsigned prot;

551 unsigned char map=MAP_FAILED, base;

552 size_t dyn=0;

553 size_t tls_image=0;

554 size_t i;

555

556 ssize_t l = read(fd, buf, sizeof buf);

557 eh = buf;

558 if (l<0) return 0;

559 if (l<sizeof *eh \|\| (eh->e_type != ET_DYN && eh->e_type != ET_EXEC))

560 goto noexec;

561 phsize = eh->e_phentsize * eh->e_phnum;

562 if (phsize > sizeof buf - sizeof *eh) {

563 allocated_buf = malloc(phsize);

564 if (!allocated_buf) return 0;

565 l = pread(fd, allocated_buf, phsize, eh->e_phoff);

566 if (l < 0) goto error;

567 if (l != phsize) goto noexec;

568 ph = ph0 = allocated_buf;

569 } else if (eh->e_phoff + phsize > l) {

570 l = pread(fd, buf+1, phsize, eh->e_phoff);

571 if (l < 0) goto error;

572 if (l != phsize) goto noexec;

573 ph = ph0 = (void *)(buf + 1);

574 } else {

575 ph = ph0 = (void )((char )buf + eh->e_phoff);

576 }

577 for (i=eh->e_phnum; i; i--, ph=(void )((char )ph+eh->e_phentsize)) {

578 if (ph->p_type == PT_DYNAMIC) {

579 dyn = ph->p_vaddr;

580 } else if (ph->p_type == PT_TLS) {

581 tls_image = ph->p_vaddr;

582 dso->tls.align = ph->p_align;

583 dso->tls.len = ph->p_filesz;

584 dso->tls.size = ph->p_memsz;

585 } else if (ph->p_type == PT_GNU_RELRO) {

586 dso->relro_start = ph->p_vaddr & -PAGE_SIZE;

587 dso->relro_end = (ph->p_vaddr + ph->p_memsz) & -PAGE_SIZ E;

588 }

589 if (ph->p_type != PT_LOAD) continue;

590 nsegs++;

591 if (ph->p_vaddr < addr_min) {

592 addr_min = ph->p_vaddr;

593 off_start = ph->p_offset;

594 prot = (((ph->p_flags&PF_R) ? PROT_READ : 0) \|

595 ((ph->p_flags&PF_W) ? PROT_WRITE: 0) \|

596 ((ph->p_flags&PF_X) ? PROT_EXEC : 0));

597 }

598 if (ph->p_vaddr+ph->p_memsz > addr_max) {

599 addr_max = ph->p_vaddr+ph->p_memsz;

600 }

601 }

602 if (!dyn) goto noexec;

603 if (DL_FDPIC && !(eh->e_flags & FDPIC_CONSTDISP_FLAG)) {

604 dso->loadmap = calloc(1, sizeof *dso->loadmap

605 + nsegs * sizeof *dso->loadmap->segs);

606 if (!dso->loadmap) goto error;

607 dso->loadmap->nsegs = nsegs;

608 for (ph=ph0, i=0; i<nsegs; ph=(void )((char )ph+eh->e_phentsiz e)) {

609 if (ph->p_type != PT_LOAD) continue;

610 prot = (((ph->p_flags&PF_R) ? PROT_READ : 0) \|

611 ((ph->p_flags&PF_W) ? PROT_WRITE: 0) \|

612 ((ph->p_flags&PF_X) ? PROT_EXEC : 0));

613 map = mmap(0, ph->p_memsz + (ph->p_vaddr & PAGE_SIZE-1),

614 prot, MAP_PRIVATE,

615 fd, ph->p_offset & -PAGE_SIZE);

616 if (map == MAP_FAILED) {

617 unmap_library(dso);

618 goto error;

619 }

620 dso->loadmap->segs[i].addr = (size_t)map +

621 (ph->p_vaddr & PAGE_SIZE-1);

622 dso->loadmap->segs[i].p_vaddr = ph->p_vaddr;

623 dso->loadmap->segs[i].p_memsz = ph->p_memsz;

624 i++;

625 if (prot & PROT_WRITE) {

626 size_t brk = (ph->p_vaddr & PAGE_SIZE-1)

627 + ph->p_filesz;

628 size_t pgbrk = brk + PAGE_SIZE-1 & -PAGE_SIZE;

629 size_t pgend = brk + ph->p_memsz - ph->p_filesz

630 + PAGE_SIZE-1 & -PAGE_SIZE;

631 if (pgend > pgbrk && mmap_fixed(map+pgbrk,

632 pgend-pgbrk, prot,

633 MAP_PRIVATE\|MAP_FIXED\|MAP_ANONYMOUS,

634 -1, off_start) == MAP_FAILED)

635 goto error;

636 memset(map + brk, 0, pgbrk-brk);

637 }

638 }

639 map = (void *)dso->loadmap->segs[0].addr;

640 map_len = 0;

641 goto done_mapping;

642 }

643 addr_max += PAGE_SIZE-1;

644 addr_max &= -PAGE_SIZE;

645 addr_min &= -PAGE_SIZE;

646 off_start &= -PAGE_SIZE;

647 map_len = addr_max - addr_min + off_start;

648 /* The first time, we map too much, possibly even more than

649 * the length of the file. This is okay because we will not

650 * use the invalid part; we just need to reserve the right

651 * amount of virtual address space to map over later. */

652 map = DL_NOMMU_SUPPORT

653 ? mmap((void *)addr_min, map_len, PROT_READ\|PROT_WRITE\|PROT_EXEC ,

654 MAP_PRIVATE\|MAP_ANONYMOUS, -1, 0)

655 : mmap((void *)addr_min, map_len, prot,

656 MAP_PRIVATE, fd, off_start);

657 if (map==MAP_FAILED) goto error;

658 dso->map = map;

659 dso->map_len = map_len;

660 /* If the loaded file is not relocatable and the requested address is

661 * not available, then the load operation must fail. */

662 if (eh->e_type != ET_DYN && addr_min && map!=(void *)addr_min) {

663 errno = EBUSY;

664 goto error;

665 }

666 base = map - addr_min;

667 dso->phdr = 0;

668 dso->phnum = 0;

669 for (ph=ph0, i=eh->e_phnum; i; i--, ph=(void )((char )ph+eh->e_phentsi ze)) {

670 if (ph->p_type != PT_LOAD) continue;

671 /* Check if the programs headers are in this load segment, and

672 * if so, record the address for use by dl_iterate_phdr. */

673 if (!dso->phdr && eh->e_phoff >= ph->p_offset

674 && eh->e_phoff+phsize <= ph->p_offset+ph->p_filesz) {

675 dso->phdr = (void *)(base + ph->p_vaddr

676 + (eh->e_phoff-ph->p_offset));

677 dso->phnum = eh->e_phnum;

678 dso->phentsize = eh->e_phentsize;

679 }

680 /* Reuse the existing mapping for the lowest-address LOAD */

681 if ((ph->p_vaddr & -PAGE_SIZE) == addr_min && !DL_NOMMU_SUPPORT)

682 continue;

683 this_min = ph->p_vaddr & -PAGE_SIZE;

684 this_max = ph->p_vaddr+ph->p_memsz+PAGE_SIZE-1 & -PAGE_SIZE;

685 off_start = ph->p_offset & -PAGE_SIZE;

686 prot = (((ph->p_flags&PF_R) ? PROT_READ : 0) \|

687 ((ph->p_flags&PF_W) ? PROT_WRITE: 0) \|

688 ((ph->p_flags&PF_X) ? PROT_EXEC : 0));

689 if (mmap_fixed(base+this_min, this_max-this_min, prot, MAP_PRIVA TE\|MAP_FIXED, fd, off_start) == MAP_FAILED)

690 goto error;

691 if (ph->p_memsz > ph->p_filesz) {

692 size_t brk = (size_t)base+ph->p_vaddr+ph->p_filesz;

693 size_t pgbrk = brk+PAGE_SIZE-1 & -PAGE_SIZE;

694 memset((void *)brk, 0, pgbrk-brk & PAGE_SIZE-1);

695 if (pgbrk-(size_t)base < this_max && mmap_fixed((void *) pgbrk, (size_t)base+this_max-pgbrk, prot, MAP_PRIVATE\|MAP_FIXED\|MAP_ANONYMOUS, - 1, 0) == MAP_FAILED)

696 goto error;

697 }

698 }

699 for (i=0; ((size_t *)(base+dyn))[i]; i+=2)

700 if (((size_t *)(base+dyn))[i]==DT_TEXTREL) {

701 if (mprotect(map, map_len, PROT_READ\|PROT_WRITE\|PROT_EXE C)

702 && errno != ENOSYS)

703 goto error;

704 break;

705 }

706 done_mapping:

707 dso->base = base;

708 dso->dynv = laddr(dso, dyn);

709 if (dso->tls.size) dso->tls.image = laddr(dso, tls_image);

710 if (!runtime) reclaim_gaps(dso);

711 free(allocated_buf);

712 return map;

713 noexec:

714 errno = ENOEXEC;

715 error:

716 if (map!=MAP_FAILED) unmap_library(dso);

717 free(allocated_buf);

718 return 0;

719 }

720

721 static int path_open(const char name, const char s, char *buf, size_t buf_size )

722 {

723 size_t l;

724 int fd;

725 for (;;) {

726 s += strspn(s, ":\n");

727 l = strcspn(s, ":\n");

728 if (l-1 >= INT_MAX) return -1;

729 if (snprintf(buf, buf_size, "%.*s/%s", (int)l, s, name) < buf_si ze) {

730 if ((fd = open(buf, O_RDONLY\|O_CLOEXEC))>=0) return fd;

731 switch (errno) {

732 case ENOENT:

733 case ENOTDIR:

734 case EACCES:

735 case ENAMETOOLONG:

736 break;

737 default:

738 /* Any negative value but -1 will inhibit

739 * futher path search. */

740 return -2;

741 }

742 }

743 s += l;

744 }

745 }

746

747 static int fixup_rpath(struct dso p, char buf, size_t buf_size)

748 {

749 size_t n, l;

750 const char s, t, *origin;

751 char *d;

752 if (p->rpath \|\| !p->rpath_orig) return 0;

753 if (!strchr(p->rpath_orig, '$')) {

754 p->rpath = p->rpath_orig;

755 return 0;

756 }

757 n = 0;

758 s = p->rpath_orig;

759 while ((t=strchr(s, '$'))) {

760 if (strncmp(t, "$ORIGIN", 7) && strncmp(t, "${ORIGIN}", 9))

761 return 0;

762 s = t+1;

763 n++;

764 }

765 if (n > SSIZE_MAX/PATH_MAX) return 0;

766

767 if (p->kernel_mapped) {

768 /* $ORIGIN searches cannot be performed for the main program

769 * when it is suid/sgid/AT_SECURE. This is because the

770 * pathname is under the control of the caller of execve.

771 * For libraries, however, $ORIGIN can be processed safely

772 * since the library's pathname came from a trusted source

773 * (either system paths or a call to dlopen). */

774 if (libc.secure)

775 return 0;

776 l = readlink("/proc/self/exe", buf, buf_size);

777 if (l == -1) switch (errno) {

778 case ENOENT:

779 case ENOTDIR:

780 case EACCES:

781 break;

782 default:

783 return -1;

784 }

785 if (l >= buf_size)

786 return 0;

787 buf[l] = 0;

788 origin = buf;

789 } else {

790 origin = p->name;

791 }

792 t = strrchr(origin, '/');

793 l = t ? t-origin : 0;

794 p->rpath = malloc(strlen(p->rpath_orig) + n*l + 1);

795 if (!p->rpath) return -1;

796

797 d = p->rpath;

798 s = p->rpath_orig;

799 while ((t=strchr(s, '$'))) {

800 memcpy(d, s, t-s);

801 d += t-s;

802 memcpy(d, origin, l);

803 d += l;

804 /* It was determined previously that the '$' is followed

805 * either by "ORIGIN" or "{ORIGIN}". */

806 s = t + 7 + 2*(t[1]=='{');

807 }

808 strcpy(d, s);

809 return 0;

810 }

811

812 static void decode_dyn(struct dso *p)

813 {

814 size_t dyn[DYN_CNT];

815 decode_vec(p->dynv, dyn, DYN_CNT);

816 p->syms = laddr(p, dyn[DT_SYMTAB]);

817 p->strings = laddr(p, dyn[DT_STRTAB]);

818 if (dyn[0]&(1<<DT_HASH))

819 p->hashtab = laddr(p, dyn[DT_HASH]);

820 if (dyn[0]&(1<<DT_RPATH))

821 p->rpath_orig = p->strings + dyn[DT_RPATH];

822 if (dyn[0]&(1<<DT_RUNPATH))

823 p->rpath_orig = p->strings + dyn[DT_RUNPATH];

824 if (dyn[0]&(1<<DT_PLTGOT))

825 p->got = laddr(p, dyn[DT_PLTGOT]);

826 if (search_vec(p->dynv, dyn, DT_GNU_HASH))

827 p->ghashtab = laddr(p, *dyn);

828 if (search_vec(p->dynv, dyn, DT_VERSYM))

829 p->versym = laddr(p, *dyn);

830 }

831

832 static size_t count_syms(struct dso *p)

833 {

834 if (p->hashtab) return p->hashtab[1];

835

836 size_t nsym, i;

837 uint32_t buckets = p->ghashtab + 4 + (p->ghashtab[2]sizeof(size_t)/4);

838 uint32_t *hashval;

839 for (i = nsym = 0; i < p->ghashtab[0]; i++) {

840 if (buckets[i] > nsym)

841 nsym = buckets[i];

842 }

843 if (nsym) {

844 hashval = buckets + p->ghashtab[0] + (nsym - p->ghashtab[1]);

845 do nsym++;

846 while (!(*hashval++ & 1));

847 }

848 return nsym;

849 }

850

851 static void *dl_mmap(size_t n)

852 {

853 void *p;

854 int prot = PROT_READ\|PROT_WRITE, flags = MAP_ANONYMOUS\|MAP_PRIVATE;

855 #ifdef SYS_mmap2

856 p = (void *)__syscall(SYS_mmap2, 0, n, prot, flags, -1, 0);

857 #else

858 p = (void *)__syscall(SYS_mmap, 0, n, prot, flags, -1, 0);

859 #endif

860 return p == MAP_FAILED ? 0 : p;

861 }

862

863 static void makefuncdescs(struct dso *p)

864 {

865 static int self_done;

866 size_t nsym = count_syms(p);

867 size_t i, size = nsym * sizeof(*p->funcdescs);

868

869 if (!self_done) {

870 p->funcdescs = dl_mmap(size);

871 self_done = 1;

872 } else {

873 p->funcdescs = malloc(size);

874 }

875 if (!p->funcdescs) {

876 if (!runtime) a_crash();

877 error("Error allocating function descriptors for %s", p->name);

878 longjmp(*rtld_fail, 1);

879 }

880 for (i=0; i<nsym; i++) {

881 if ((p->syms[i].st_info&0xf)==STT_FUNC && p->syms[i].st_shndx) {

882 p->funcdescs[i].addr = laddr(p, p->syms[i].st_value);

883 p->funcdescs[i].got = p->got;

884 } else {

885 p->funcdescs[i].addr = 0;

886 p->funcdescs[i].got = 0;

887 }

888 }

889 }

890

891 static struct dso load_library(const char name, struct dso *needed_by)

892 {

893 char buf[2*NAME_MAX+2];

894 const char *pathname;

895 unsigned char *map;

896 struct dso *p, temp_dso = {0};

897 int fd;

898 struct stat st;

899 size_t alloc_size;

900 int n_th = 0;

901 int is_self = 0;

902

903 if (!*name) {

904 errno = EINVAL;

905 return 0;

906 }

907

908 /* Catch and block attempts to reload the implementation itself */

909 if (name[0]=='l' && name[1]=='i' && name[2]=='b') {

910 static const char *rp, reserved[] =

911 "c\0pthread\0rt\0m\0dl\0util\0xnet\0";

912 char *z = strchr(name, '.');

913 if (z) {

914 size_t l = z-name;

915 for (rp=reserved; *rp && strncmp(name+3, rp, l-3); rp+=s trlen(rp)+1);

916 if (*rp) {

917 if (ldd_mode) {

918 /* Track which names have been resolved

919 * and only report each one once. */

920 static unsigned reported;

921 unsigned mask = 1U<<(rp-reserved);

922 if (!(reported & mask)) {

923 reported \|= mask;

924 dprintf(1, "\t%s => %s (%p)\n",

925 name, ldso.name,

926 ldso.base);

927 }

928 }

929 is_self = 1;

930 }

931 }

932 }

933 if (!strcmp(name, ldso.name)) is_self = 1;

934 if (is_self) {

935 if (!ldso.prev) {

936 tail->next = &ldso;

937 ldso.prev = tail;

938 tail = ldso.next ? ldso.next : &ldso;

939 }

940 return &ldso;

941 }

942 if (strchr(name, '/')) {

943 pathname = name;

944 fd = open(name, O_RDONLY\|O_CLOEXEC);

945 } else {

946 /* Search for the name to see if it's already loaded */

947 for (p=head->next; p; p=p->next) {

948 if (p->shortname && !strcmp(p->shortname, name)) {

949 p->refcnt++;

950 return p;

951 }

952 }

953 if (strlen(name) > NAME_MAX) return 0;

954 fd = -1;

955 if (env_path) fd = path_open(name, env_path, buf, sizeof buf);

956 for (p=needed_by; fd == -1 && p; p=p->needed_by) {

957 if (fixup_rpath(p, buf, sizeof buf) < 0)

958 fd = -2; /* Inhibit further search. */

959 if (p->rpath)

960 fd = path_open(name, p->rpath, buf, sizeof buf);

961 }

962 if (fd == -1) {

963 if (!sys_path) {

964 char *prefix = 0;

965 size_t prefix_len;

966 if (ldso.name[0]=='/') {

967 char s, t, *z;

968 for (s=t=z=ldso.name; *s; s++)

969 if (*s=='/') z=t, t=s;

970 prefix_len = z-ldso.name;

971 if (prefix_len < PATH_MAX)

972 prefix = ldso.name;

973 }

974 if (!prefix) {

975 prefix = "";

976 prefix_len = 0;

977 }

978 char etc_ldso_path[prefix_len + 1

979 + sizeof "/etc/ld-musl-" LDSO_ARCH ".pat h"];

980 snprintf(etc_ldso_path, sizeof etc_ldso_path,

981 "%.*s/etc/ld-musl-" LDSO_ARCH ".path",

982 (int)prefix_len, prefix);

983 FILE *f = fopen(etc_ldso_path, "rbe");

984 if (f) {

985 if (getdelim(&sys_path, (size_t[1]){0}, 0, f) <= 0) {

986 free(sys_path);

987 sys_path = "";

988 }

989 fclose(f);

990 } else if (errno != ENOENT) {

991 sys_path = "";

992 }

993 }

994 if (!sys_path) sys_path = "/lib:/usr/local/lib:/usr/lib" ;

995 fd = path_open(name, sys_path, buf, sizeof buf);

996 }

997 pathname = buf;

998 }

999 if (fd < 0) return 0;

1000 if (fstat(fd, &st) < 0) {

1001 close(fd);

1002 return 0;

1003 }

1004 for (p=head->next; p; p=p->next) {

1005 if (p->dev == st.st_dev && p->ino == st.st_ino) {

1006 /* If this library was previously loaded with a

1007 * pathname but a search found the same inode,

1008 * setup its shortname so it can be found by name. */

1009 if (!p->shortname && pathname != name)

1010 p->shortname = strrchr(p->name, '/')+1;

1011 close(fd);

1012 p->refcnt++;

1013 return p;

1014 }

1015 }

1016 map = noload ? 0 : map_library(fd, &temp_dso);

1017 close(fd);

1018 if (!map) return 0;

1019

1020 /* Allocate storage for the new DSO. When there is TLS, this

1021 * storage must include a reservation for all pre-existing

1022 * threads to obtain copies of both the new TLS, and an

1023 * extended DTV capable of storing an additional slot for

1024 * the newly-loaded DSO. */

1025 alloc_size = sizeof *p + strlen(pathname) + 1;

1026 if (runtime && temp_dso.tls.image) {

1027 size_t per_th = temp_dso.tls.size + temp_dso.tls.align

1028 + sizeof(void ) (tls_cnt+3);

1029 n_th = libc.threads_minus_1 + 1;

1030 if (n_th > SSIZE_MAX / per_th) alloc_size = SIZE_MAX;

1031 else alloc_size += n_th * per_th;

1032 }

1033 p = calloc(1, alloc_size);

1034 if (!p) {

1035 unmap_library(&temp_dso);

1036 return 0;

1037 }

1038 memcpy(p, &temp_dso, sizeof temp_dso);

1039 decode_dyn(p);

1040 p->dev = st.st_dev;

1041 p->ino = st.st_ino;

1042 p->refcnt = 1;

1043 p->needed_by = needed_by;

1044 p->name = p->buf;

1045 strcpy(p->name, pathname);

1046 /* Add a shortname only if name arg was not an explicit pathname. */

1047 if (pathname != name) p->shortname = strrchr(p->name, '/')+1;

1048 if (p->tls.image) {

1049 p->tls_id = ++tls_cnt;

1050 tls_align = MAXP2(tls_align, p->tls.align);

1051 #ifdef TLS_ABOVE_TP

1052 p->tls.offset = tls_offset + ( (tls_align-1) &

1053 -(tls_offset + (uintptr_t)p->tls.image) );

1054 tls_offset += p->tls.size;

1055 #else

1056 tls_offset += p->tls.size + p->tls.align - 1;

1057 tls_offset -= (tls_offset + (uintptr_t)p->tls.image)

1058 & (p->tls.align-1);

1059 p->tls.offset = tls_offset;

1060 #endif

1061 p->new_dtv = (void *)(-sizeof(size_t) &

1062 (uintptr_t)(p->name+strlen(p->name)+sizeof(size_t)));

1063 p->new_tls = (void )(p->new_dtv + n_th(tls_cnt+1));

1064 if (tls_tail) tls_tail->next = &p->tls;

1065 else libc.tls_head = &p->tls;

1066 tls_tail = &p->tls;

1067 }

1068

1069 tail->next = p;

1070 p->prev = tail;

1071 tail = p;

1072

1073 if (DL_FDPIC) makefuncdescs(p);

1074

1075 if (ldd_mode) dprintf(1, "\t%s => %s (%p)\n", name, pathname, p->base);

1076

1077 return p;

1078 }

1079

1080 static void load_deps(struct dso *p)

1081 {

1082 size_t i, ndeps=0;

1083 struct dso *deps = &p->deps, tmp, *dep;

1084 for (; p; p=p->next) {

1085 for (i=0; p->dynv[i]; i+=2) {

1086 if (p->dynv[i] != DT_NEEDED) continue;

1087 dep = load_library(p->strings + p->dynv[i+1], p);

1088 if (!dep) {

1089 error("Error loading shared library %s: %m (need ed by %s)",

1090 p->strings + p->dynv[i+1], p->name);

1091 if (runtime) longjmp(*rtld_fail, 1);

1092 continue;

1093 }

1094 if (runtime) {

1095 tmp = realloc(deps, sizeof(tmp)*(ndeps+2));

1096 if (!tmp) longjmp(*rtld_fail, 1);

1097 tmp[ndeps++] = dep;

1098 tmp[ndeps] = 0;

1099 *deps = tmp;

1100 }

1101 }

1102 }

1103 }

1104

1105 static void load_preload(char *s)

1106 {

1107 int tmp;

1108 char *z;

1109 for (z=s; *z; s=z) {

1110 for ( ; s && (isspace(s) \|\| *s==':'); s++);

1111 for (z=s; z && !isspace(z) && *z!=':'; z++);

1112 tmp = *z;

1113 *z = 0;

1114 load_library(s, 0);

1115 *z = tmp;

1116 }

1117 }

1118

1119 static void make_global(struct dso *p)

1120 {

1121 for (; p; p=p->next) p->global = 1;

1122 }

1123

1124 static void do_mips_relocs(struct dso p, size_t got)

1125 {

1126 size_t i, j, rel[2];

1127 unsigned char *base = p->base;

1128 i=0; search_vec(p->dynv, &i, DT_MIPS_LOCAL_GOTNO);

1129 if (p==&ldso) {

1130 got += i;

1131 } else {

1132 while (i--) *got++ += (size_t)base;

1133 }

1134 j=0; search_vec(p->dynv, &j, DT_MIPS_GOTSYM);

1135 i=0; search_vec(p->dynv, &i, DT_MIPS_SYMTABNO);

1136 Sym *sym = p->syms + j;

1137 rel[0] = (unsigned char *)got - base;

1138 for (i-=j; i; i--, sym++, rel[0]+=sizeof(size_t)) {

1139 rel[1] = sym-p->syms << 8 \| R_MIPS_JUMP_SLOT;

1140 do_relocs(p, rel, sizeof rel, 2);

1141 }

1142 }

1143

1144 static void reloc_all(struct dso *p)

1145 {

1146 size_t dyn[DYN_CNT];

1147 for (; p; p=p->next) {

1148 if (p->relocated) continue;

1149 decode_vec(p->dynv, dyn, DYN_CNT);

1150 if (NEED_MIPS_GOT_RELOCS)

1151 do_mips_relocs(p, laddr(p, dyn[DT_PLTGOT]));

1152 do_relocs(p, laddr(p, dyn[DT_JMPREL]), dyn[DT_PLTRELSZ],

1153 2+(dyn[DT_PLTREL]==DT_RELA));

1154 do_relocs(p, laddr(p, dyn[DT_REL]), dyn[DT_RELSZ], 2);

1155 do_relocs(p, laddr(p, dyn[DT_RELA]), dyn[DT_RELASZ], 3);

1156

1157 if (head != &ldso && p->relro_start != p->relro_end &&

1158 mprotect(laddr(p, p->relro_start), p->relro_end-p->relro_sta rt, PROT_READ)

1159 && errno != ENOSYS) {

1160 error("Error relocating %s: RELRO protection failed: %m" ,

1161 p->name);

1162 if (runtime) longjmp(*rtld_fail, 1);

1163 }

1164

1165 p->relocated = 1;

1166 }

1167 }

1168

1169 static void kernel_mapped_dso(struct dso *p)

1170 {

1171 size_t min_addr = -1, max_addr = 0, cnt;

1172 Phdr *ph = p->phdr;

1173 for (cnt = p->phnum; cnt--; ph = (void )((char )ph + p->phentsize)) {

1174 if (ph->p_type == PT_DYNAMIC) {

1175 p->dynv = laddr(p, ph->p_vaddr);

1176 } else if (ph->p_type == PT_GNU_RELRO) {

1177 p->relro_start = ph->p_vaddr & -PAGE_SIZE;

1178 p->relro_end = (ph->p_vaddr + ph->p_memsz) & -PAGE_SIZE;

1179 }

1180 if (ph->p_type != PT_LOAD) continue;

1181 if (ph->p_vaddr < min_addr)

1182 min_addr = ph->p_vaddr;

1183 if (ph->p_vaddr+ph->p_memsz > max_addr)

1184 max_addr = ph->p_vaddr+ph->p_memsz;

1185 }

1186 min_addr &= -PAGE_SIZE;

1187 max_addr = (max_addr + PAGE_SIZE-1) & -PAGE_SIZE;

1188 p->map = p->base + min_addr;

1189 p->map_len = max_addr - min_addr;

1190 p->kernel_mapped = 1;

1191 }

1192

1193 void __libc_exit_fini()

1194 {

1195 struct dso *p;

1196 size_t dyn[DYN_CNT];

1197 for (p=fini_head; p; p=p->fini_next) {

1198 if (!p->constructed) continue;

1199 decode_vec(p->dynv, dyn, DYN_CNT);

1200 if (dyn[0] & (1<<DT_FINI_ARRAY)) {

1201 size_t n = dyn[DT_FINI_ARRAYSZ]/sizeof(size_t);

1202 size_t fn = (size_t )laddr(p, dyn[DT_FINI_ARRAY])+n;

1203 while (n--) ((void ()(void))--fn)();

1204 }

1205 #ifndef NO_LEGACY_INITFINI

1206 if ((dyn[0] & (1<<DT_FINI)) && dyn[DT_FINI])

1207 fpaddr(p, dyn[DT_FINI])();

1208 #endif

1209 }

1210 }

1211

1212 static void do_init_fini(struct dso *p)

1213 {

1214 size_t dyn[DYN_CNT];

1215 int need_locking = libc.threads_minus_1;

1216 /* Allow recursive calls that arise when a library calls

1217 * dlopen from one of its constructors, but block any

1218 * other threads until all ctors have finished. */

1219 if (need_locking) pthread_mutex_lock(&init_fini_lock);

1220 for (; p; p=p->prev) {

1221 if (p->constructed) continue;

1222 p->constructed = 1;

1223 decode_vec(p->dynv, dyn, DYN_CNT);

1224 if (dyn[0] & ((1<<DT_FINI) \| (1<<DT_FINI_ARRAY))) {

1225 p->fini_next = fini_head;

1226 fini_head = p;

1227 }

1228 #ifndef NO_LEGACY_INITFINI

1229 if ((dyn[0] & (1<<DT_INIT)) && dyn[DT_INIT])

1230 fpaddr(p, dyn[DT_INIT])();

1231 #endif

1232 if (dyn[0] & (1<<DT_INIT_ARRAY)) {

1233 size_t n = dyn[DT_INIT_ARRAYSZ]/sizeof(size_t);

1234 size_t *fn = laddr(p, dyn[DT_INIT_ARRAY]);

1235 while (n--) ((void ()(void))fn++)();

1236 }

1237 if (!need_locking && libc.threads_minus_1) {

1238 need_locking = 1;

1239 pthread_mutex_lock(&init_fini_lock);

1240 }

1241 }

1242 if (need_locking) pthread_mutex_unlock(&init_fini_lock);

1243 }

1244

1245 void __libc_start_init(void)

1246 {

1247 do_init_fini(tail);

1248 }

1249

1250 static void dl_debug_state(void)

1251 {

1252 }

1253

1254 weak_alias(dl_debug_state, _dl_debug_state);

1255

1256 void __init_tls(size_t *auxv)

1257 {

1258 }

1259

1260 __attribute__((__visibility__("hidden")))

1261 void __tls_get_new(size_t v)

1262 {

1263 pthread_t self = __pthread_self();

1264

1265 /* Block signals to make accessing new TLS async-signal-safe */

1266 sigset_t set;

1267 __block_all_sigs(&set);

1268 if (v[0]<=(size_t)self->dtv[0]) {

1269 __restore_sigs(&set);

1270 return (char *)self->dtv[v[0]]+v[1]+DTP_OFFSET;

1271 }

1272

1273 /* This is safe without any locks held because, if the caller

1274 * is able to request the Nth entry of the DTV, the DSO list

1275 * must be valid at least that far out and it was synchronized

1276 * at program startup or by an already-completed call to dlopen. */

1277 struct dso *p;

1278 for (p=head; p->tls_id != v[0]; p=p->next);

1279

1280 /* Get new DTV space from new DSO if needed */

1281 if (v[0] > (size_t)self->dtv[0]) {

1282 void **newdtv = p->new_dtv +

1283 (v[0]+1)*a_fetch_add(&p->new_dtv_idx,1);

1284 memcpy(newdtv, self->dtv,

1285 ((size_t)self->dtv[0]+1) * sizeof(void *));

1286 newdtv[0] = (void *)v[0];

1287 self->dtv = self->dtv_copy = newdtv;

1288 }

1289

1290 /* Get new TLS memory from all new DSOs up to the requested one */

1291 unsigned char *mem;

1292 for (p=head; ; p=p->next) {

1293 if (!p->tls_id \|\| self->dtv[p->tls_id]) continue;

1294 mem = p->new_tls + (p->tls.size + p->tls.align)

1295 * a_fetch_add(&p->new_tls_idx,1);

1296 mem += ((uintptr_t)p->tls.image - (uintptr_t)mem)

1297 & (p->tls.align-1);

1298 self->dtv[p->tls_id] = mem;

1299 memcpy(mem, p->tls.image, p->tls.len);

1300 if (p->tls_id == v[0]) break;

1301 }

1302 __restore_sigs(&set);

1303 return mem + v[1] + DTP_OFFSET;

1304 }

1305

1306 static void update_tls_size()

1307 {

1308 libc.tls_cnt = tls_cnt;

1309 libc.tls_align = tls_align;

1310 libc.tls_size = ALIGN(

1311 (1+tls_cnt) * sizeof(void *) +

1312 tls_offset +

1313 sizeof(struct pthread) +

1314 tls_align * 2,

1315 tls_align);

1316 }

1317

1318 /* Stage 1 of the dynamic linker is defined in dlstart.c. It calls the

1319 * following stage 2 and stage 3 functions via primitive symbolic lookup

1320 * since it does not have access to their addresses to begin with. */

1321

1322 /* Stage 2 of the dynamic linker is called after relative relocations

1323 * have been processed. It can make function calls to static functions

1324 * and access string literals and static data, but cannot use extern

1325 * symbols. Its job is to perform symbolic relocations on the dynamic

1326 * linker itself, but some of the relocations performed may need to be

1327 * replaced later due to copy relocations in the main program. */

1328

1329 __attribute__((__visibility__("hidden")))

1330 void __dls2(unsigned char base, size_t sp)

1331 {

1332 if (DL_FDPIC) {

1333 void p1 = (void )sp[-2];

1334 void p2 = (void )sp[-1];

1335 if (!p1) {

1336 size_t *auxv, aux[AUX_CNT];

1337 for (auxv=sp+1+sp+1; auxv; auxv++); auxv++;

1338 decode_vec(auxv, aux, AUX_CNT);

1339 if (aux[AT_BASE]) ldso.base = (void *)aux[AT_BASE];

1340 else ldso.base = (void *)(aux[AT_PHDR] & -4096);

1341 }

1342 app_loadmap = p2 ? p1 : 0;

1343 ldso.loadmap = p2 ? p2 : p1;

1344 ldso.base = laddr(&ldso, 0);

1345 } else {

1346 ldso.base = base;

1347 }

1348 Ehdr ehdr = (void )ldso.base;

1349 ldso.name = ldso.shortname = "libc.so";

1350 ldso.global = 1;

1351 ldso.phnum = ehdr->e_phnum;

1352 ldso.phdr = laddr(&ldso, ehdr->e_phoff);

1353 ldso.phentsize = ehdr->e_phentsize;

1354 kernel_mapped_dso(&ldso);

1355 decode_dyn(&ldso);

1356

1357 if (DL_FDPIC) makefuncdescs(&ldso);

1358

1359 /* Prepare storage for to save clobbered REL addends so they

1360 * can be reused in stage 3. There should be very few. If

1361 * something goes wrong and there are a huge number, abort

1362 * instead of risking stack overflow. */

1363 size_t dyn[DYN_CNT];

1364 decode_vec(ldso.dynv, dyn, DYN_CNT);

1365 size_t *rel = laddr(&ldso, dyn[DT_REL]);

1366 size_t rel_size = dyn[DT_RELSZ];

1367 size_t symbolic_rel_cnt = 0;

1368 apply_addends_to = rel;

1369 for (; rel_size; rel+=2, rel_size-=2*sizeof(size_t))

1370 if (!IS_RELATIVE(rel[1], ldso.syms)) symbolic_rel_cnt++;

1371 if (symbolic_rel_cnt >= ADDEND_LIMIT) a_crash();

1372 size_t addends[symbolic_rel_cnt+1];

1373 saved_addends = addends;

1374

1375 head = &ldso;

1376 reloc_all(&ldso);

1377

1378 ldso.relocated = 0;

1379

1380 /* Call dynamic linker stage-3, __dls3, looking it up

1381 * symbolically as a barrier against moving the address

1382 * load across the above relocation processing. */

1383 struct symdef dls3_def = find_sym(&ldso, "__dls3", 0);

1384 if (DL_FDPIC) ((stage3_func)&ldso.funcdescs[dls3_def.sym-ldso.syms])(sp) ;

1385 else ((stage3_func)laddr(&ldso, dls3_def.sym->st_value))(sp);

1386 }

1387

1388 /* Stage 3 of the dynamic linker is called with the dynamic linker/libc

1389 * fully functional. Its job is to load (if not already loaded) and

1390 * process dependencies and relocations for the main application and

1391 * transfer control to its entry point. */

1392

1393 _Noreturn void __dls3(size_t *sp)

1394 {

1395 static struct dso app, vdso;

1396 size_t aux[AUX_CNT], *auxv;

1397 size_t i;

1398 char *env_preload=0;

1399 size_t vdso_base;

1400 int argc = *sp;

1401 char *argv = (void )(sp+1);

1402 char **argv_orig = argv;

1403 char **envp = argv+argc+1;

1404

1405 /* Find aux vector just past environ[] and use it to initialize

1406 * global data that may be needed before we can make syscalls. */

1407 __environ = envp;

1408 for (i=argc+1; argv[i]; i++);

1409 libc.auxv = auxv = (void *)(argv+i+1);

1410 decode_vec(auxv, aux, AUX_CNT);

1411 __hwcap = aux[AT_HWCAP];

1412 libc.page_size = aux[AT_PAGESZ];

1413 libc.secure = ((aux[0]&0x7800)!=0x7800 \|\| aux[AT_UID]!=aux[AT_EUID]

1414 \|\| aux[AT_GID]!=aux[AT_EGID] \|\| aux[AT_SECURE]);

1415

1416 /* Setup early thread pointer in builtin_tls for ldso/libc itself to

1417 * use during dynamic linking. If possible it will also serve as the

1418 * thread pointer at runtime. */

1419 libc.tls_size = sizeof builtin_tls;

1420 libc.tls_align = tls_align;

1421 if (__init_tp(__copy_tls((void *)builtin_tls)) < 0) {

1422 a_crash();

1423 }

1424

1425 /* Only trust user/env if kernel says we're not suid/sgid */

1426 if (!libc.secure) {

1427 env_path = getenv("LD_LIBRARY_PATH");

1428 env_preload = getenv("LD_PRELOAD");

1429 }

1430

1431 /* If the main program was already loaded by the kernel,

1432 * AT_PHDR will point to some location other than the dynamic

1433 * linker's program headers. */

1434 if (aux[AT_PHDR] != (size_t)ldso.phdr) {

1435 size_t interp_off = 0;

1436 size_t tls_image = 0;

1437 /* Find load address of the main program, via AT_PHDR vs PT_PHDR . */

1438 Phdr phdr = app.phdr = (void )aux[AT_PHDR];

1439 app.phnum = aux[AT_PHNUM];

1440 app.phentsize = aux[AT_PHENT];

1441 for (i=aux[AT_PHNUM]; i; i--, phdr=(void )((char )phdr + aux[A T_PHENT])) {

1442 if (phdr->p_type == PT_PHDR)

1443 app.base = (void *)(aux[AT_PHDR] - phdr->p_vaddr );

1444 else if (phdr->p_type == PT_INTERP)

1445 interp_off = (size_t)phdr->p_vaddr;

1446 else if (phdr->p_type == PT_TLS) {

1447 tls_image = phdr->p_vaddr;

1448 app.tls.len = phdr->p_filesz;

1449 app.tls.size = phdr->p_memsz;

1450 app.tls.align = phdr->p_align;

1451 }

1452 }

1453 if (DL_FDPIC) app.loadmap = app_loadmap;

1454 if (app.tls.size) app.tls.image = laddr(&app, tls_image);

1455 if (interp_off) ldso.name = laddr(&app, interp_off);

1456 if ((aux[0] & (1UL<<AT_EXECFN))

1457 && strncmp((char *)aux[AT_EXECFN], "/proc/", 6))

1458 app.name = (char *)aux[AT_EXECFN];

1459 else

1460 app.name = argv[0];

1461 kernel_mapped_dso(&app);

1462 } else {

1463 int fd;

1464 char *ldname = argv[0];

1465 size_t l = strlen(ldname);

1466 if (l >= 3 && !strcmp(ldname+l-3, "ldd")) ldd_mode = 1;

1467 argv++;

1468 while (argv[0] && argv[0][0]=='-' && argv[0][1]=='-') {

1469 char *opt = argv[0]+2;

1470 argv++ = (void )-1;

1471 if (!*opt) {

1472 break;

1473 } else if (!memcmp(opt, "list", 5)) {

1474 ldd_mode = 1;

1475 } else if (!memcmp(opt, "library-path", 12)) {

1476 if (opt[12]=='=') env_path = opt+13;

1477 else if (opt[12]) *argv = 0;

1478 else if (argv) env_path = argv++;

1479 } else if (!memcmp(opt, "preload", 7)) {

1480 if (opt[7]=='=') env_preload = opt+8;

1481 else if (opt[7]) *argv = 0;

1482 else if (argv) env_preload = argv++;

1483 } else {

1484 argv[0] = 0;

1485 }

1486 }

1487 argv[-1] = (void *)(argc - (argv-argv_orig));

1488 if (!argv[0]) {

1489 dprintf(2, "musl libc (" LDSO_ARCH ")\n"

1490 "Version %s\n"

1491 "Dynamic Program Loader\n"

1492 "Usage: %s [options] [--] pathname%s\n",

1493 __libc_get_version(), ldname,

1494 ldd_mode ? "" : " [args]");

1495 _exit(1);

1496 }

1497 fd = open(argv[0], O_RDONLY);

1498 if (fd < 0) {

1499 dprintf(2, "%s: cannot load %s: %s\n", ldname, argv[0], strerror(errno));

1500 _exit(1);

1501 }

1502 runtime = 1;

1503 Ehdr ehdr = (void )map_library(fd, &app);

1504 if (!ehdr) {

1505 dprintf(2, "%s: %s: Not a valid dynamic program\n", ldna me, argv[0]);

1506 _exit(1);

1507 }

1508 runtime = 0;

1509 close(fd);

1510 ldso.name = ldname;

1511 app.name = argv[0];

1512 aux[AT_ENTRY] = (size_t)laddr(&app, ehdr->e_entry);

1513 /* Find the name that would have been used for the dynamic

1514 * linker had ldd not taken its place. */

1515 if (ldd_mode) {

1516 for (i=0; i<app.phnum; i++) {

1517 if (app.phdr[i].p_type == PT_INTERP)

1518 ldso.name = laddr(&app, app.phdr[i].p_va ddr);

1519 }

1520 dprintf(1, "\t%s (%p)\n", ldso.name, ldso.base);

1521 }

1522 }

1523 if (app.tls.size) {

1524 libc.tls_head = &app.tls;

1525 app.tls_id = tls_cnt = 1;

1526 #ifdef TLS_ABOVE_TP

1527 app.tls.offset = 0;

1528 tls_offset = app.tls.size

1529 + ( -((uintptr_t)app.tls.image + app.tls.size)

1530 & (app.tls.align-1) );

1531 #else

1532 tls_offset = app.tls.offset = app.tls.size

1533 + ( -((uintptr_t)app.tls.image + app.tls.size)

1534 & (app.tls.align-1) );

1535 #endif

1536 tls_align = MAXP2(tls_align, app.tls.align);

1537 }

1538 app.global = 1;

1539 decode_dyn(&app);

1540 if (DL_FDPIC) {

1541 makefuncdescs(&app);

1542 if (!app.loadmap) {

1543 app.loadmap = (void *)&app_dummy_loadmap;

1544 app.loadmap->nsegs = 1;

1545 app.loadmap->segs[0].addr = (size_t)app.map;

1546 app.loadmap->segs[0].p_vaddr = (size_t)app.map

1547 - (size_t)app.base;

1548 app.loadmap->segs[0].p_memsz = app.map_len;

1549 }

1550 argv[-3] = (void *)app.loadmap;

1551 }

1552

1553 /* Attach to vdso, if provided by the kernel */

1554 if (search_vec(auxv, &vdso_base, AT_SYSINFO_EHDR)) {

1555 Ehdr ehdr = (void )vdso_base;

1556 Phdr phdr = vdso.phdr = (void )(vdso_base + ehdr->e_phoff);

1557 vdso.phnum = ehdr->e_phnum;

1558 vdso.phentsize = ehdr->e_phentsize;

1559 for (i=ehdr->e_phnum; i; i--, phdr=(void )((char )phdr + ehdr- >e_phentsize)) {

1560 if (phdr->p_type == PT_DYNAMIC)

1561 vdso.dynv = (void *)(vdso_base + phdr->p_offset) ;

1562 if (phdr->p_type == PT_LOAD)

1563 vdso.base = (void *)(vdso_base - phdr->p_vaddr + phdr->p_offset);

1564 }

1565 vdso.name = "";

1566 vdso.shortname = "linux-gate.so.1";

1567 vdso.global = 1;

1568 vdso.relocated = 1;

1569 decode_dyn(&vdso);

1570 vdso.prev = &ldso;

1571 ldso.next = &vdso;

1572 }

1573

1574 /* Initial dso chain consists only of the app. */

1575 head = tail = &app;

1576

1577 /* Donate unused parts of app and library mapping to malloc */

1578 reclaim_gaps(&app);

1579 reclaim_gaps(&ldso);

1580

1581 /* Load preload/needed libraries, add their symbols to the global

1582 * namespace, and perform all remaining relocations. */

1583 if (env_preload) load_preload(env_preload);

1584 load_deps(&app);

1585 make_global(&app);

1586

1587 #ifndef DYNAMIC_IS_RO

1588 for (i=0; app.dynv[i]; i+=2)

1589 if (app.dynv[i]==DT_DEBUG)

1590 app.dynv[i+1] = (size_t)&debug;

1591 #endif

1592

1593 /* The main program must be relocated LAST since it may contin

1594 * copy relocations which depend on libraries' relocations. */

1595 reloc_all(app.next);

1596 reloc_all(&app);

1597

1598 update_tls_size();

1599 if (libc.tls_size > sizeof builtin_tls \|\| tls_align > MIN_TLS_ALIGN) {

1600 void *initial_tls = calloc(libc.tls_size, 1);

1601 if (!initial_tls) {

1602 dprintf(2, "%s: Error getting %zu bytes thread-local sto rage: %m\n",

1603 argv[0], libc.tls_size);

1604 _exit(127);

1605 }

1606 if (__init_tp(__copy_tls(initial_tls)) < 0) {

1607 a_crash();

1608 }

1609 } else {

1610 size_t tmp_tls_size = libc.tls_size;

1611 pthread_t self = __pthread_self();

1612 /* Temporarily set the tls size to the full size of

1613 * builtin_tls so that __copy_tls will use the same layout

1614 * as it did for before. Then check, just to be safe. */

1615 libc.tls_size = sizeof builtin_tls;

1616 if (__copy_tls((void*)builtin_tls) != self) a_crash();

1617 libc.tls_size = tmp_tls_size;

1618 }

1619 static_tls_cnt = tls_cnt;

1620

1621 if (ldso_fail) _exit(127);

1622 if (ldd_mode) _exit(0);

1623

1624 /* Switch to runtime mode: any further failures in the dynamic

1625 * linker are a reportable failure rather than a fatal startup

1626 * error. */

1627 runtime = 1;

1628

1629 debug.ver = 1;

1630 debug.bp = dl_debug_state;

1631 debug.head = head;

1632 debug.base = ldso.base;

1633 debug.state = 0;

1634 _dl_debug_state();

1635

1636 errno = 0;

1637

1638 CRTJMP((void *)aux[AT_ENTRY], argv-1);

1639 for(;;);

1640 }

1641

1642 void dlopen(const char file, int mode)

1643 {

1644 struct dso volatile p, orig_tail, *next;

1645 struct tls_module *orig_tls_tail;

1646 size_t orig_tls_cnt, orig_tls_offset, orig_tls_align;

1647 size_t i;

1648 int cs;

1649 jmp_buf jb;

1650

1651 if (!file) return head;

1652

1653 pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);

1654 pthread_rwlock_wrlock(&lock);

1655 __inhibit_ptc();

1656

1657 p = 0;

1658 orig_tls_tail = tls_tail;

1659 orig_tls_cnt = tls_cnt;

1660 orig_tls_offset = tls_offset;

1661 orig_tls_align = tls_align;

1662 orig_tail = tail;

1663 noload = mode & RTLD_NOLOAD;

1664

1665 rtld_fail = &jb;

1666 if (setjmp(*rtld_fail)) {

1667 /* Clean up anything new that was (partially) loaded */

1668 if (p && p->deps) for (i=0; p->deps[i]; i++)

1669 if (p->deps[i]->global < 0)

1670 p->deps[i]->global = 0;

1671 for (p=orig_tail->next; p; p=next) {

1672 next = p->next;

1673 while (p->td_index) {

1674 void *tmp = p->td_index->next;

1675 free(p->td_index);

1676 p->td_index = tmp;

1677 }

1678 free(p->funcdescs);

1679 if (p->rpath != p->rpath_orig)

1680 free(p->rpath);

1681 free(p->deps);

1682 unmap_library(p);

1683 free(p);

1684 }

1685 if (!orig_tls_tail) libc.tls_head = 0;

1686 tls_tail = orig_tls_tail;

1687 tls_cnt = orig_tls_cnt;

1688 tls_offset = orig_tls_offset;

1689 tls_align = orig_tls_align;

1690 tail = orig_tail;

1691 tail->next = 0;

1692 p = 0;

1693 goto end;

1694 } else p = load_library(file, head);

1695

1696 if (!p) {

1697 error(noload ?

1698 "Library %s is not already loaded" :

1699 "Error loading shared library %s: %m",

1700 file);

1701 goto end;

1702 }

1703

1704 /* First load handling */

1705 if (!p->deps) {

1706 load_deps(p);

1707 if (p->deps) for (i=0; p->deps[i]; i++)

1708 if (!p->deps[i]->global)

1709 p->deps[i]->global = -1;

1710 if (!p->global) p->global = -1;

1711 reloc_all(p);

1712 if (p->deps) for (i=0; p->deps[i]; i++)

1713 if (p->deps[i]->global < 0)

1714 p->deps[i]->global = 0;

1715 if (p->global < 0) p->global = 0;

1716 }

1717

1718 if (mode & RTLD_GLOBAL) {

1719 if (p->deps) for (i=0; p->deps[i]; i++)

1720 p->deps[i]->global = 1;

1721 p->global = 1;

1722 }

1723

1724 update_tls_size();

1725 _dl_debug_state();

1726 orig_tail = tail;

1727 end:

1728 __release_ptc();

1729 if (p) gencnt++;

1730 pthread_rwlock_unlock(&lock);

1731 if (p) do_init_fini(orig_tail);

1732 pthread_setcancelstate(cs, 0);

1733 return p;

1734 }

1735

1736 static int invalid_dso_handle(void *h)

1737 {

1738 struct dso *p;

1739 for (p=head; p; p=p->next) if (h==p) return 0;

1740 error("Invalid library handle %p", (void *)h);

1741 return 1;

1742 }

1743

1744 static void *addr2dso(size_t a)

1745 {

1746 struct dso *p;

1747 size_t i;

1748 if (DL_FDPIC) for (p=head; p; p=p->next) {

1749 i = count_syms(p);

1750 if (a-(size_t)p->funcdescs < isizeof(p->funcdescs))

1751 return p;

1752 }

1753 for (p=head; p; p=p->next) {

1754 if (DL_FDPIC && p->loadmap) {

1755 for (i=0; i<p->loadmap->nsegs; i++) {

1756 if (a-p->loadmap->segs[i].p_vaddr

1757 < p->loadmap->segs[i].p_memsz)

1758 return p;

1759 }

1760 } else {

1761 if (a-(size_t)p->map < p->map_len)

1762 return p;

1763 }

1764 }

1765 return 0;

1766 }

1767

1768 void __tls_get_addr(size_t );

1769

1770 static void do_dlsym(struct dso p, const char s, void ra)

1771 {

1772 size_t i;

1773 uint32_t h = 0, gh = 0, *ght;

1774 Sym *sym;

1775 if (p == head \|\| p == RTLD_DEFAULT \|\| p == RTLD_NEXT) {

1776 if (p == RTLD_DEFAULT) {

1777 p = head;

1778 } else if (p == RTLD_NEXT) {

1779 p = addr2dso((size_t)ra);

1780 if (!p) p=head;

1781 p = p->next;

1782 }

1783 struct symdef def = find_sym(p, s, 0);

1784 if (!def.sym) goto failed;

1785 if ((def.sym->st_info&0xf) == STT_TLS)

1786 return __tls_get_addr((size_t []){def.dso->tls_id, def.s ym->st_value});

1787 if (DL_FDPIC && (def.sym->st_info&0xf) == STT_FUNC)

1788 return def.dso->funcdescs + (def.sym - def.dso->syms);

1789 return laddr(def.dso, def.sym->st_value);

1790 }

1791 if (invalid_dso_handle(p))

1792 return 0;

1793 if ((ght = p->ghashtab)) {

1794 gh = gnu_hash(s);

1795 sym = gnu_lookup(gh, ght, p, s);

1796 } else {

1797 h = sysv_hash(s);

1798 sym = sysv_lookup(s, h, p);

1799 }

1800 if (sym && (sym->st_info&0xf) == STT_TLS)

1801 return __tls_get_addr((size_t []){p->tls_id, sym->st_value});

1802 if (DL_FDPIC && sym && sym->st_shndx && (sym->st_info&0xf) == STT_FUNC)

1803 return p->funcdescs + (sym - p->syms);

1804 if (sym && sym->st_value && (1<<(sym->st_info&0xf) & OK_TYPES))

1805 return laddr(p, sym->st_value);

1806 if (p->deps) for (i=0; p->deps[i]; i++) {

1807 if ((ght = p->deps[i]->ghashtab)) {

1808 if (!gh) gh = gnu_hash(s);

1809 sym = gnu_lookup(gh, ght, p->deps[i], s);

1810 } else {

1811 if (!h) h = sysv_hash(s);

1812 sym = sysv_lookup(s, h, p->deps[i]);

1813 }

1814 if (sym && (sym->st_info&0xf) == STT_TLS)

1815 return __tls_get_addr((size_t []){p->deps[i]->tls_id, sy m->st_value});

1816 if (DL_FDPIC && sym && sym->st_shndx && (sym->st_info&0xf) == ST T_FUNC)

1817 return p->deps[i]->funcdescs + (sym - p->deps[i]->syms);

1818 if (sym && sym->st_value && (1<<(sym->st_info&0xf) & OK_TYPES))

1819 return laddr(p->deps[i], sym->st_value);

1820 }

1821 failed:

1822 error("Symbol not found: %s", s);

1823 return 0;

1824 }

1825

1826 int __dladdr(const void addr, Dl_info info)

1827 {

1828 struct dso *p;

1829 Sym sym, bestsym;

1830 uint32_t nsym;

1831 char *strings;

1832 void *best = 0;

1833

1834 pthread_rwlock_rdlock(&lock);

1835 p = addr2dso((size_t)addr);

1836 pthread_rwlock_unlock(&lock);

1837

1838 if (!p) return 0;

1839

1840 sym = p->syms;

1841 strings = p->strings;

1842 nsym = count_syms(p);

1843

1844 if (DL_FDPIC) {

1845 size_t idx = ((size_t)addr-(size_t)p->funcdescs)

1846 / sizeof(*p->funcdescs);

1847 if (idx < nsym && (sym[idx].st_info&0xf) == STT_FUNC) {

1848 best = p->funcdescs + idx;

1849 bestsym = sym + idx;

1850 }

1851 }

1852

1853 if (!best) for (; nsym; nsym--, sym++) {

1854 if (sym->st_value

1855 && (1<<(sym->st_info&0xf) & OK_TYPES)

1856 && (1<<(sym->st_info>>4) & OK_BINDS)) {

1857 void *symaddr = laddr(p, sym->st_value);

1858 if (symaddr > addr \|\| symaddr < best)

1859 continue;

1860 best = symaddr;

1861 bestsym = sym;

1862 if (addr == symaddr)

1863 break;

1864 }

1865 }

1866

1867 if (!best) return 0;

1868

1869 if (DL_FDPIC && (bestsym->st_info&0xf) == STT_FUNC)

1870 best = p->funcdescs + (bestsym - p->syms);

1871

1872 info->dli_fname = p->name;

1873 info->dli_fbase = p->base;

1874 info->dli_sname = strings + bestsym->st_name;

1875 info->dli_saddr = best;

1876

1877 return 1;

1878 }

1879

1880 __attribute__((__visibility__("hidden")))

1881 void __dlsym(void restrict p, const char restrict s, void restrict ra)

1882 {

1883 void *res;

1884 pthread_rwlock_rdlock(&lock);

1885 res = do_dlsym(p, s, ra);

1886 pthread_rwlock_unlock(&lock);

1887 return res;

1888 }

1889

1890 int dl_iterate_phdr(int(callback)(struct dl_phdr_info info, size_t size, void data), void data)

1891 {

1892 struct dso *current;

1893 struct dl_phdr_info info;

1894 int ret = 0;

1895 for(current = head; current;) {

1896 info.dlpi_addr = (uintptr_t)current->base;

1897 info.dlpi_name = current->name;

1898 info.dlpi_phdr = current->phdr;

1899 info.dlpi_phnum = current->phnum;

1900 info.dlpi_adds = gencnt;

1901 info.dlpi_subs = 0;

1902 info.dlpi_tls_modid = current->tls_id;

1903 info.dlpi_tls_data = current->tls.image;

1904

1905 ret = (callback)(&info, sizeof (info), data);

1906

1907 if (ret != 0) break;

1908

1909 pthread_rwlock_rdlock(&lock);

1910 current = current->next;

1911 pthread_rwlock_unlock(&lock);

1912 }

1913 return ret;

1914 }

1915 #else

1916 static int invalid_dso_handle(void *h)

1917 {

1918 error("Invalid library handle %p", (void *)h);

1919 return 1;

1920 }

1921 void dlopen(const char file, int mode)

1922 {

1923 error("Dynamic loading not supported");

1924 return 0;

1925 }

1926 void __dlsym(void restrict p, const char restrict s, void restrict ra)

1927 {

1928 error("Symbol not found: %s", s);

1929 return 0;

1930 }

1931 int __dladdr (const void addr, Dl_info info)

1932 {

1933 return 0;

1934 }

1935 #endif

1936

1937 int __dlinfo(void dso, int req, void res)

1938 {

1939 if (invalid_dso_handle(dso)) return -1;

1940 if (req != RTLD_DI_LINKMAP) {

1941 error("Unsupported request %d", req);

1942 return -1;

1943 }

1944 (struct link_map *)res = dso;

1945 return 0;

1946 }

1947

1948 char *dlerror()

1949 {

1950 pthread_t self = __pthread_self();

1951 if (!self->dlerror_flag) return 0;

1952 self->dlerror_flag = 0;

1953 char *s = self->dlerror_buf;

1954 if (s == (void *)-1)

1955 return "Dynamic linker failed to allocate memory for error messa ge";

1956 else

1957 return s;

1958 }

1959

1960 int dlclose(void *p)

1961 {

1962 return invalid_dso_handle(p);

1963 }

1964

1965 void __dl_thread_cleanup(void)

1966 {

1967 pthread_t self = __pthread_self();

1968 if (self->dlerror_buf != (void *)-1)

1969 free(self->dlerror_buf);

1970 }

1971

1972 static void error(const char *fmt, ...)

1973 {

1974 va_list ap;

1975 va_start(ap, fmt);

1976 #ifdef SHARED

1977 if (!runtime) {

1978 vdprintf(2, fmt, ap);

1979 dprintf(2, "\n");

1980 ldso_fail = 1;

1981 va_end(ap);

1982 return;

1983 }

1984 #endif

1985 pthread_t self = __pthread_self();

1986 if (self->dlerror_buf != (void *)-1)

1987 free(self->dlerror_buf);

1988 size_t len = vsnprintf(0, 0, fmt, ap);

1989 va_end(ap);

1990 char *buf = malloc(len+1);

1991 if (buf) {

1992 va_start(ap, fmt);

1993 vsnprintf(buf, len+1, fmt, ap);

1994 va_end(ap);

1995 } else {

1996 buf = (void *)-1;

1997 }

1998 self->dlerror_buf = buf;

1999 self->dlerror_flag = 1;

2000 }

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