source: asp3_tinet_ecnl_rx/trunk/musl-1.1.18/ldso/dynlink.~c@ 337

Last change on this file since 337 was 337, checked in by coas-nagasima, 6 years ago

ASP3版ECNLを追加
File size: 56.4 KB
Line 
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
24static void error(const char *, ...);
25
26#define MAXP2(a,b) (-(-(a)&-(b)))
27#define ALIGN(x,y) ((x)+(y)-1 & -(y))
28
29struct debug {
30 int ver;
31 void *head;
32 void (*bp)(void);
33 int state;
34 void *base;
35};
36
37struct td_index {
38 size_t args[2];
39 struct td_index *next;
40};
41
42struct dso {
43#if DL_FDPIC
44 struct fdpic_loadmap *loadmap;
45#else
46 unsigned char *base;
47#endif
48 char *name;
49 size_t *dynv;
50 struct dso *next, *prev;
51
52 Phdr *phdr;
53 int phnum;
54 size_t phentsize;
55 Sym *syms;
56 Elf_Symndx *hashtab;
57 uint32_t *ghashtab;
58 int16_t *versym;
59 char *strings;
60 struct dso *syms_next, *lazy_next;
61 size_t *lazy, lazy_cnt;
62 unsigned char *map;
63 size_t map_len;
64 dev_t dev;
65 ino_t ino;
66 char relocated;
67 char constructed;
68 char kernel_mapped;
69 struct dso **deps, *needed_by;
70 char *rpath_orig, *rpath;
71 struct tls_module tls;
72 size_t tls_id;
73 size_t relro_start, relro_end;
74 void **new_dtv;
75 unsigned char *new_tls;
76 volatile int new_dtv_idx, new_tls_idx;
77 struct td_index *td_index;
78 struct dso *fini_next;
79 char *shortname;
80#if DL_FDPIC
81 unsigned char *base;
82#else
83 struct fdpic_loadmap *loadmap;
84#endif
85 struct funcdesc {
86 void *addr;
87 size_t *got;
88 } *funcdescs;
89 size_t *got;
90 char buf[];
91};
92
93struct symdef {
94 Sym *sym;
95 struct dso *dso;
96};
97
98int __init_tp(void *);
99void __init_libc(char **, char *);
100void *__copy_tls(unsigned char *);
101
102__attribute__((__visibility__("hidden")))
103const char *__libc_get_version(void);
104
105static struct builtin_tls {
106 char c;
107 struct pthread pt;
108 void *space[16];
109} builtin_tls[1];
110#define MIN_TLS_ALIGN offsetof(struct builtin_tls, pt)
111
112#define ADDEND_LIMIT 4096
113static size_t *saved_addends, *apply_addends_to;
114
115static struct dso ldso;
116static struct dso *head, *tail, *fini_head, *syms_tail, *lazy_head;
117static char *env_path, *sys_path;
118static unsigned long long gencnt;
119static int runtime;
120static int ldd_mode;
121static int ldso_fail;
122static int noload;
123static jmp_buf *rtld_fail;
124static pthread_rwlock_t lock;
125static struct debug debug;
126static struct tls_module *tls_tail;
127static size_t tls_cnt, tls_offset, tls_align = MIN_TLS_ALIGN;
128static size_t static_tls_cnt;
129static pthread_mutex_t init_fini_lock = { ._m_type = PTHREAD_MUTEX_RECURSIVE };
130static struct fdpic_loadmap *app_loadmap;
131static struct fdpic_dummy_loadmap app_dummy_loadmap;
132static struct dso *const nodeps_dummy;
133
134struct debug *_dl_debug_addr = &debug;
135
136#ifndef __c2__
137__attribute__((__visibility__("hidden")))
138void (*const __init_array_start)(void)=0, (*const __fini_array_start)(void)=0;
139
140__attribute__((__visibility__("hidden")))
141extern void (*const __init_array_end)(void), (*const __fini_array_end)(void);
142
143weak_alias(__init_array_start, __init_array_end);
144weak_alias(__fini_array_start, __fini_array_end);
145#else
146void(*const __init_array_start)(void) = 0, (*const __fini_array_start)(void) = 0;
147#define __init_array_end __init_array_start
148#define __fini_array_end __fini_array_start
149#endif
150
151static int dl_strcmp(const char *l, const char *r)
152{
153 for (; *l==*r && *l; l++, r++);
154 return *(unsigned char *)l - *(unsigned char *)r;
155}
156#define strcmp(l,r) dl_strcmp(l,r)
157
158/* Compute load address for a virtual address in a given dso. */
159#if DL_FDPIC
160static void *laddr(const struct dso *p, size_t v)
161{
162 size_t j=0;
163 if (!p->loadmap) return p->base + v;
164 for (j=0; v-p->loadmap->segs[j].p_vaddr >= p->loadmap->segs[j].p_memsz; j++);
165 return (void *)(v - p->loadmap->segs[j].p_vaddr + p->loadmap->segs[j].addr);
166}
167#define fpaddr(p, v) ((void (*)())&(struct funcdesc){ \
168 laddr(p, v), (p)->got })
169#else
170#define laddr(p, v) (void *)((p)->base + (v))
171#define fpaddr(p, v) ((void (*)())laddr(p, v))
172#endif
173
174static void decode_vec(size_t *v, size_t *a, size_t cnt)
175{
176 size_t i;
177 for (i=0; i<cnt; i++) a[i] = 0;
178 for (; v[0]; v+=2) if (v[0]-1<cnt-1) {
179 a[0] |= 1UL<<v[0];
180 a[v[0]] = v[1];
181 }
182}
183
184static int search_vec(size_t *v, size_t *r, size_t key)
185{
186 for (; v[0]!=key; v+=2)
187 if (!v[0]) return 0;
188 *r = v[1];
189 return 1;
190}
191
192static uint32_t sysv_hash(const char *s0)
193{
194 const unsigned char *s = (void *)s0;
195 uint_fast32_t h = 0;
196 while (*s) {
197 h = 16*h + *s++;
198 h ^= h>>24 & 0xf0;
199 }
200 return h & 0xfffffff;
201}
202
203static uint32_t gnu_hash(const char *s0)
204{
205 const unsigned char *s = (void *)s0;
206 uint_fast32_t h = 5381;
207 for (; *s; s++)
208 h += h*32 + *s;
209 return h;
210}
211
212static Sym *sysv_lookup(const char *s, uint32_t h, struct dso *dso)
213{
214 size_t i;
215 Sym *syms = dso->syms;
216 Elf_Symndx *hashtab = dso->hashtab;
217 char *strings = dso->strings;
218 for (i=hashtab[2+h%hashtab[0]]; i; i=hashtab[2+hashtab[0]+i]) {
219 if ((!dso->versym || dso->versym[i] >= 0)
220 && (!strcmp(s, strings+syms[i].st_name)))
221 return syms+i;
222 }
223 return 0;
224}
225
226static Sym *gnu_lookup(uint32_t h1, uint32_t *hashtab, struct dso *dso, const char *s)
227{
228 uint32_t nbuckets = hashtab[0];
229 uint32_t *buckets = hashtab + 4 + hashtab[2]*(sizeof(size_t)/4);
230 uint32_t i = buckets[h1 % nbuckets];
231
232 if (!i) return 0;
233
234 uint32_t *hashval = buckets + nbuckets + (i - hashtab[1]);
235
236 for (h1 |= 1; ; i++) {
237 uint32_t h2 = *hashval++;
238 if ((h1 == (h2|1)) && (!dso->versym || dso->versym[i] >= 0)
239 && !strcmp(s, dso->strings + dso->syms[i].st_name))
240 return dso->syms+i;
241 if (h2 & 1) break;
242 }
243
244 return 0;
245}
246
247static Sym *gnu_lookup_filtered(uint32_t h1, uint32_t *hashtab, struct dso *dso, const char *s, uint32_t fofs, size_t fmask)
248{
249 const size_t *bloomwords = (const void *)(hashtab+4);
250 size_t f = bloomwords[fofs & (hashtab[2]-1)];
251 if (!(f & fmask)) return 0;
252
253 f >>= (h1 >> hashtab[3]) % (8 * sizeof f);
254 if (!(f & 1)) return 0;
255
256 return gnu_lookup(h1, hashtab, dso, s);
257}
258
259#define OK_TYPES (1<<STT_NOTYPE | 1<<STT_OBJECT | 1<<STT_FUNC | 1<<STT_COMMON | 1<<STT_TLS)
260#define OK_BINDS (1<<STB_GLOBAL | 1<<STB_WEAK | 1<<STB_GNU_UNIQUE)
261
262#ifndef ARCH_SYM_REJECT_UND
263#define ARCH_SYM_REJECT_UND(s) 0
264#endif
265
266static struct symdef find_sym(struct dso *dso, const char *s, int need_def)
267{
268 uint32_t h = 0, gh = gnu_hash(s), gho = gh / (8*sizeof(size_t)), *ght;
269 size_t ghm = 1ul << gh % (8*sizeof(size_t));
270 struct symdef def = {0};
271 for (; dso; dso=dso->syms_next) {
272 Sym *sym;
273 if ((ght = dso->ghashtab)) {
274 sym = gnu_lookup_filtered(gh, ght, dso, s, gho, ghm);
275 } else {
276 if (!h) h = sysv_hash(s);
277 sym = sysv_lookup(s, h, dso);
278 }
279 if (!sym) continue;
280 if (!sym->st_shndx)
281 if (need_def || (sym->st_info&0xf) == STT_TLS
282 || ARCH_SYM_REJECT_UND(sym))
283 continue;
284 if (!sym->st_value)
285 if ((sym->st_info&0xf) != STT_TLS)
286 continue;
287 if (!(1<<(sym->st_info&0xf) & OK_TYPES)) continue;
288 if (!(1<<(sym->st_info>>4) & OK_BINDS)) continue;
289 def.sym = sym;
290 def.dso = dso;
291 break;
292 }
293 return def;
294}
295
296__attribute__((__visibility__("hidden")))
297ptrdiff_t __tlsdesc_static(), __tlsdesc_dynamic();
298
299static void do_relocs(struct dso *dso, size_t *rel, size_t rel_size, size_t stride)
300{
301 unsigned char *base = dso->base;
302 Sym *syms = dso->syms;
303 char *strings = dso->strings;
304 Sym *sym;
305 const char *name;
306 void *ctx;
307 int type;
308 int sym_index;
309 struct symdef def;
310 size_t *reloc_addr;
311 size_t sym_val;
312 size_t tls_val;
313 size_t addend;
314 int skip_relative = 0, reuse_addends = 0, save_slot = 0;
315
316 if (dso == &ldso) {
317 /* Only ldso's REL table needs addend saving/reuse. */
318 if (rel == apply_addends_to)
319 reuse_addends = 1;
320 skip_relative = 1;
321 }
322
323 for (; rel_size; rel+=stride, rel_size-=stride*sizeof(size_t)) {
324 if (skip_relative && IS_RELATIVE(rel[1], dso->syms)) continue;
325 type = R_TYPE(rel[1]);
326 if (type == REL_NONE) continue;
327 reloc_addr = laddr(dso, rel[0]);
328
329 if (stride > 2) {
330 addend = rel[2];
331 } else if (type==REL_GOT || type==REL_PLT|| type==REL_COPY) {
332 addend = 0;
333 } else if (reuse_addends) {
334 /* Save original addend in stage 2 where the dso
335 * chain consists of just ldso; otherwise read back
336 * saved addend since the inline one was clobbered. */
337 if (head==&ldso)
338 saved_addends[save_slot] = *reloc_addr;
339 addend = saved_addends[save_slot++];
340 } else {
341 addend = *reloc_addr;
342 }
343
344 sym_index = R_SYM(rel[1]);
345 if (sym_index) {
346 sym = syms + sym_index;
347 name = strings + sym->st_name;
348 ctx = type==REL_COPY ? head->syms_next : head;
349 def = (sym->st_info&0xf) == STT_SECTION
350 ? (struct symdef){ .dso = dso, .sym = sym }
351 : find_sym(ctx, name, type==REL_PLT);
352 if (!def.sym && (sym->st_shndx != SHN_UNDEF
353 || sym->st_info>>4 != STB_WEAK)) {
354 if (dso->lazy && (type==REL_PLT || type==REL_GOT)) {
355 dso->lazy[3*dso->lazy_cnt+0] = rel[0];
356 dso->lazy[3*dso->lazy_cnt+1] = rel[1];
357 dso->lazy[3*dso->lazy_cnt+2] = addend;
358 dso->lazy_cnt++;
359 continue;
360 }
361 error("Error relocating %s: %s: symbol not found",
362 dso->name, name);
363 if (runtime) longjmp(*rtld_fail, 1);
364 continue;
365 }
366 } else {
367 sym = 0;
368 def.sym = 0;
369 def.dso = dso;
370 }
371
372 sym_val = def.sym ? (size_t)laddr(def.dso, def.sym->st_value) : 0;
373 tls_val = def.sym ? def.sym->st_value : 0;
374
375 switch(type) {
376 case REL_NONE:
377 break;
378 case REL_OFFSET:
379 addend -= (size_t)reloc_addr;
380 case REL_SYMBOLIC:
381 case REL_GOT:
382 case REL_PLT:
383 *reloc_addr = sym_val + addend;
384 break;
385 case REL_RELATIVE:
386 *reloc_addr = (size_t)base + addend;
387 break;
388 case REL_SYM_OR_REL:
389 if (sym) *reloc_addr = sym_val + addend;
390 else *reloc_addr = (size_t)base + addend;
391 break;
392 case REL_COPY:
393 memcpy(reloc_addr, (void *)sym_val, sym->st_size);
394 break;
395 case REL_OFFSET32:
396 *(uint32_t *)reloc_addr = sym_val + addend
397 - (size_t)reloc_addr;
398 break;
399 case REL_FUNCDESC:
400 *reloc_addr = def.sym ? (size_t)(def.dso->funcdescs
401 + (def.sym - def.dso->syms)) : 0;
402 break;
403 case REL_FUNCDESC_VAL:
404 if ((sym->st_info&0xf) == STT_SECTION) *reloc_addr += sym_val;
405 else *reloc_addr = sym_val;
406 reloc_addr[1] = def.sym ? (size_t)def.dso->got : 0;
407 break;
408 case REL_DTPMOD:
409 *reloc_addr = def.dso->tls_id;
410 break;
411 case REL_DTPOFF:
412 *reloc_addr = tls_val + addend - DTP_OFFSET;
413 break;
414#ifdef TLS_ABOVE_TP
415 case REL_TPOFF:
416 *reloc_addr = tls_val + def.dso->tls.offset + TPOFF_K + addend;
417 break;
418#else
419 case REL_TPOFF:
420 *reloc_addr = tls_val - def.dso->tls.offset + addend;
421 break;
422 case REL_TPOFF_NEG:
423 *reloc_addr = def.dso->tls.offset - tls_val + addend;
424 break;
425#endif
426 case REL_TLSDESC:
427 if (stride<3) addend = reloc_addr[1];
428 if (runtime && def.dso->tls_id >= static_tls_cnt) {
429 struct td_index *new = malloc(sizeof *new);
430 if (!new) {
431 error(
432 "Error relocating %s: cannot allocate TLSDESC for %s",
433 dso->name, sym ? name : "(local)" );
434 longjmp(*rtld_fail, 1);
435 }
436 new->next = dso->td_index;
437 dso->td_index = new;
438 new->args[0] = def.dso->tls_id;
439 new->args[1] = tls_val + addend;
440 reloc_addr[0] = (size_t)__tlsdesc_dynamic;
441 reloc_addr[1] = (size_t)new;
442 } else {
443 reloc_addr[0] = (size_t)__tlsdesc_static;
444#ifdef TLS_ABOVE_TP
445 reloc_addr[1] = tls_val + def.dso->tls.offset
446 + TPOFF_K + addend;
447#else
448 reloc_addr[1] = tls_val - def.dso->tls.offset
449 + addend;
450#endif
451 }
452 break;
453 default:
454 error("Error relocating %s: unsupported relocation type %d",
455 dso->name, type);
456 if (runtime) longjmp(*rtld_fail, 1);
457 continue;
458 }
459 }
460}
461
462static void redo_lazy_relocs()
463{
464 struct dso *p = lazy_head, *next;
465 lazy_head = 0;
466 for (; p; p=next) {
467 next = p->lazy_next;
468 size_t size = p->lazy_cnt*3*sizeof(size_t);
469 p->lazy_cnt = 0;
470 do_relocs(p, p->lazy, size, 3);
471 if (p->lazy_cnt) {
472 p->lazy_next = lazy_head;
473 lazy_head = p;
474 } else {
475 free(p->lazy);
476 p->lazy = 0;
477 p->lazy_next = 0;
478 }
479 }
480}
481
482/* A huge hack: to make up for the wastefulness of shared libraries
483 * needing at least a page of dirty memory even if they have no global
484 * data, we reclaim the gaps at the beginning and end of writable maps
485 * and "donate" them to the heap by setting up minimal malloc
486 * structures and then freeing them. */
487
488static void reclaim(struct dso *dso, size_t start, size_t end)
489{
490 size_t *a, *z;
491 if (start >= dso->relro_start && start < dso->relro_end) start = dso->relro_end;
492 if (end >= dso->relro_start && end < dso->relro_end) end = dso->relro_start;
493 start = start + 6*sizeof(size_t)-1 & -4*sizeof(size_t);
494 end = (end & -4*sizeof(size_t)) - 2*sizeof(size_t);
495 if (start>end || end-start < 4*sizeof(size_t)) return;
496 a = laddr(dso, start);
497 z = laddr(dso, end);
498 a[-2] = 1;
499 a[-1] = z[0] = end-start + 2*sizeof(size_t) | 1;
500 z[1] = 1;
501 free(a);
502}
503
504static void reclaim_gaps(struct dso *dso)
505{
506 Phdr *ph = dso->phdr;
507 size_t phcnt = dso->phnum;
508
509 if (DL_FDPIC) return; // FIXME
510 for (; phcnt--; ph=(void *)((char *)ph+dso->phentsize)) {
511 if (ph->p_type!=PT_LOAD) continue;
512 if ((ph->p_flags&(PF_R|PF_W))!=(PF_R|PF_W)) continue;
513 reclaim(dso, ph->p_vaddr & -PAGE_SIZE, ph->p_vaddr);
514 reclaim(dso, ph->p_vaddr+ph->p_memsz,
515 ph->p_vaddr+ph->p_memsz+PAGE_SIZE-1 & -PAGE_SIZE);
516 }
517}
518
519static void *mmap_fixed(void *p, size_t n, int prot, int flags, int fd, off_t off)
520{
521 static int no_map_fixed;
522 char *q;
523 if (!no_map_fixed) {
524 q = mmap(p, n, prot, flags|MAP_FIXED, fd, off);
525 if (!DL_NOMMU_SUPPORT || q != MAP_FAILED || errno != EINVAL)
526 return q;
527 no_map_fixed = 1;
528 }
529 /* Fallbacks for MAP_FIXED failure on NOMMU kernels. */
530 if (flags & MAP_ANONYMOUS) {
531 memset(p, 0, n);
532 return p;
533 }
534 ssize_t r;
535 if (lseek(fd, off, SEEK_SET) < 0) return MAP_FAILED;
536 for (q=p; n; q+=r, off+=r, n-=r) {
537 r = read(fd, q, n);
538 if (r < 0 && errno != EINTR) return MAP_FAILED;
539 if (!r) {
540 memset(q, 0, n);
541 break;
542 }
543 }
544 return p;
545}
546
547static void unmap_library(struct dso *dso)
548{
549 if (dso->loadmap) {
550 size_t i;
551 for (i=0; i<dso->loadmap->nsegs; i++) {
552 if (!dso->loadmap->segs[i].p_memsz)
553 continue;
554 munmap((void *)dso->loadmap->segs[i].addr,
555 dso->loadmap->segs[i].p_memsz);
556 }
557 free(dso->loadmap);
558 } else if (dso->map && dso->map_len) {
559 munmap(dso->map, dso->map_len);
560 }
561}
562
563static void *map_library(int fd, struct dso *dso)
564{
565 Ehdr buf[(896+sizeof(Ehdr))/sizeof(Ehdr)];
566 void *allocated_buf=0;
567 size_t phsize;
568 size_t addr_min=SIZE_MAX, addr_max=0, map_len;
569 size_t this_min, this_max;
570 size_t nsegs = 0;
571 off_t off_start;
572 Ehdr *eh;
573 Phdr *ph, *ph0;
574 unsigned prot;
575 unsigned char *map=MAP_FAILED, *base;
576 size_t dyn=0;
577 size_t tls_image=0;
578 size_t i;
579
580 ssize_t l = read(fd, buf, sizeof buf);
581 eh = buf;
582 if (l<0) return 0;
583 if (l<sizeof *eh || (eh->e_type != ET_DYN && eh->e_type != ET_EXEC))
584 goto noexec;
585 phsize = eh->e_phentsize * eh->e_phnum;
586 if (phsize > sizeof buf - sizeof *eh) {
587 allocated_buf = malloc(phsize);
588 if (!allocated_buf) return 0;
589 l = pread(fd, allocated_buf, phsize, eh->e_phoff);
590 if (l < 0) goto error;
591 if (l != phsize) goto noexec;
592 ph = ph0 = allocated_buf;
593 } else if (eh->e_phoff + phsize > l) {
594 l = pread(fd, buf+1, phsize, eh->e_phoff);
595 if (l < 0) goto error;
596 if (l != phsize) goto noexec;
597 ph = ph0 = (void *)(buf + 1);
598 } else {
599 ph = ph0 = (void *)((char *)buf + eh->e_phoff);
600 }
601 for (i=eh->e_phnum; i; i--, ph=(void *)((char *)ph+eh->e_phentsize)) {
602 if (ph->p_type == PT_DYNAMIC) {
603 dyn = ph->p_vaddr;
604 } else if (ph->p_type == PT_TLS) {
605 tls_image = ph->p_vaddr;
606 dso->tls.align = ph->p_align;
607 dso->tls.len = ph->p_filesz;
608 dso->tls.size = ph->p_memsz;
609 } else if (ph->p_type == PT_GNU_RELRO) {
610 dso->relro_start = ph->p_vaddr & -PAGE_SIZE;
611 dso->relro_end = (ph->p_vaddr + ph->p_memsz) & -PAGE_SIZE;
612 }
613 if (ph->p_type != PT_LOAD) continue;
614 nsegs++;
615 if (ph->p_vaddr < addr_min) {
616 addr_min = ph->p_vaddr;
617 off_start = ph->p_offset;
618 prot = (((ph->p_flags&PF_R) ? PROT_READ : 0) |
619 ((ph->p_flags&PF_W) ? PROT_WRITE: 0) |
620 ((ph->p_flags&PF_X) ? PROT_EXEC : 0));
621 }
622 if (ph->p_vaddr+ph->p_memsz > addr_max) {
623 addr_max = ph->p_vaddr+ph->p_memsz;
624 }
625 }
626 if (!dyn) goto noexec;
627 if (DL_FDPIC && !(eh->e_flags & FDPIC_CONSTDISP_FLAG)) {
628 dso->loadmap = calloc(1, sizeof *dso->loadmap
629 + nsegs * sizeof *dso->loadmap->segs);
630 if (!dso->loadmap) goto error;
631 dso->loadmap->nsegs = nsegs;
632 for (ph=ph0, i=0; i<nsegs; ph=(void *)((char *)ph+eh->e_phentsize)) {
633 if (ph->p_type != PT_LOAD) continue;
634 prot = (((ph->p_flags&PF_R) ? PROT_READ : 0) |
635 ((ph->p_flags&PF_W) ? PROT_WRITE: 0) |
636 ((ph->p_flags&PF_X) ? PROT_EXEC : 0));
637 map = mmap(0, ph->p_memsz + (ph->p_vaddr & PAGE_SIZE-1),
638 prot, MAP_PRIVATE,
639 fd, ph->p_offset & -PAGE_SIZE);
640 if (map == MAP_FAILED) {
641 unmap_library(dso);
642 goto error;
643 }
644 dso->loadmap->segs[i].addr = (size_t)map +
645 (ph->p_vaddr & PAGE_SIZE-1);
646 dso->loadmap->segs[i].p_vaddr = ph->p_vaddr;
647 dso->loadmap->segs[i].p_memsz = ph->p_memsz;
648 i++;
649 if (prot & PROT_WRITE) {
650 size_t brk = (ph->p_vaddr & PAGE_SIZE-1)
651 + ph->p_filesz;
652 size_t pgbrk = brk + PAGE_SIZE-1 & -PAGE_SIZE;
653 size_t pgend = brk + ph->p_memsz - ph->p_filesz
654 + PAGE_SIZE-1 & -PAGE_SIZE;
655 if (pgend > pgbrk && mmap_fixed(map+pgbrk,
656 pgend-pgbrk, prot,
657 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS,
658 -1, off_start) == MAP_FAILED)
659 goto error;
660 memset(map + brk, 0, pgbrk-brk);
661 }
662 }
663 map = (void *)dso->loadmap->segs[0].addr;
664 map_len = 0;
665 goto done_mapping;
666 }
667 addr_max += PAGE_SIZE-1;
668 addr_max &= -PAGE_SIZE;
669 addr_min &= -PAGE_SIZE;
670 off_start &= -PAGE_SIZE;
671 map_len = addr_max - addr_min + off_start;
672 /* The first time, we map too much, possibly even more than
673 * the length of the file. This is okay because we will not
674 * use the invalid part; we just need to reserve the right
675 * amount of virtual address space to map over later. */
676 map = DL_NOMMU_SUPPORT
677 ? mmap((void *)addr_min, map_len, PROT_READ|PROT_WRITE|PROT_EXEC,
678 MAP_PRIVATE|MAP_ANONYMOUS, -1, 0)
679 : mmap((void *)addr_min, map_len, prot,
680 MAP_PRIVATE, fd, off_start);
681 if (map==MAP_FAILED) goto error;
682 dso->map = map;
683 dso->map_len = map_len;
684 /* If the loaded file is not relocatable and the requested address is
685 * not available, then the load operation must fail. */
686 if (eh->e_type != ET_DYN && addr_min && map!=(void *)addr_min) {
687 errno = EBUSY;
688 goto error;
689 }
690 base = map - addr_min;
691 dso->phdr = 0;
692 dso->phnum = 0;
693 for (ph=ph0, i=eh->e_phnum; i; i--, ph=(void *)((char *)ph+eh->e_phentsize)) {
694 if (ph->p_type != PT_LOAD) continue;
695 /* Check if the programs headers are in this load segment, and
696 * if so, record the address for use by dl_iterate_phdr. */
697 if (!dso->phdr && eh->e_phoff >= ph->p_offset
698 && eh->e_phoff+phsize <= ph->p_offset+ph->p_filesz) {
699 dso->phdr = (void *)(base + ph->p_vaddr
700 + (eh->e_phoff-ph->p_offset));
701 dso->phnum = eh->e_phnum;
702 dso->phentsize = eh->e_phentsize;
703 }
704 /* Reuse the existing mapping for the lowest-address LOAD */
705 if ((ph->p_vaddr & -PAGE_SIZE) == addr_min && !DL_NOMMU_SUPPORT)
706 continue;
707 this_min = ph->p_vaddr & -PAGE_SIZE;
708 this_max = ph->p_vaddr+ph->p_memsz+PAGE_SIZE-1 & -PAGE_SIZE;
709 off_start = ph->p_offset & -PAGE_SIZE;
710 prot = (((ph->p_flags&PF_R) ? PROT_READ : 0) |
711 ((ph->p_flags&PF_W) ? PROT_WRITE: 0) |
712 ((ph->p_flags&PF_X) ? PROT_EXEC : 0));
713 if (mmap_fixed(base+this_min, this_max-this_min, prot, MAP_PRIVATE|MAP_FIXED, fd, off_start) == MAP_FAILED)
714 goto error;
715 if (ph->p_memsz > ph->p_filesz) {
716 size_t brk = (size_t)base+ph->p_vaddr+ph->p_filesz;
717 size_t pgbrk = brk+PAGE_SIZE-1 & -PAGE_SIZE;
718 memset((void *)brk, 0, pgbrk-brk & PAGE_SIZE-1);
719 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)
720 goto error;
721 }
722 }
723 for (i=0; ((size_t *)(base+dyn))[i]; i+=2)
724 if (((size_t *)(base+dyn))[i]==DT_TEXTREL) {
725 if (mprotect(map, map_len, PROT_READ|PROT_WRITE|PROT_EXEC)
726 && errno != ENOSYS)
727 goto error;
728 break;
729 }
730done_mapping:
731 dso->base = base;
732 dso->dynv = laddr(dso, dyn);
733 if (dso->tls.size) dso->tls.image = laddr(dso, tls_image);
734 if (!runtime) reclaim_gaps(dso);
735 free(allocated_buf);
736 return map;
737noexec:
738 errno = ENOEXEC;
739error:
740 if (map!=MAP_FAILED) unmap_library(dso);
741 free(allocated_buf);
742 return 0;
743}
744
745static int path_open(const char *name, const char *s, char *buf, size_t buf_size)
746{
747 size_t l;
748 int fd;
749 for (;;) {
750 s += strspn(s, ":\n");
751 l = strcspn(s, ":\n");
752 if (l-1 >= INT_MAX) return -1;
753 if (snprintf(buf, buf_size, "%.*s/%s", (int)l, s, name) < buf_size) {
754 if ((fd = open(buf, O_RDONLY|O_CLOEXEC))>=0) return fd;
755 switch (errno) {
756 case ENOENT:
757 case ENOTDIR:
758 case EACCES:
759 case ENAMETOOLONG:
760 break;
761 default:
762 /* Any negative value but -1 will inhibit
763 * futher path search. */
764 return -2;
765 }
766 }
767 s += l;
768 }
769}
770
771static int fixup_rpath(struct dso *p, char *buf, size_t buf_size)
772{
773 size_t n, l;
774 const char *s, *t, *origin;
775 char *d;
776 if (p->rpath || !p->rpath_orig) return 0;
777 if (!strchr(p->rpath_orig, '$')) {
778 p->rpath = p->rpath_orig;
779 return 0;
780 }
781 n = 0;
782 s = p->rpath_orig;
783 while ((t=strchr(s, '$'))) {
784 if (strncmp(t, "$ORIGIN", 7) && strncmp(t, "${ORIGIN}", 9))
785 return 0;
786 s = t+1;
787 n++;
788 }
789 if (n > SSIZE_MAX/PATH_MAX) return 0;
790
791 if (p->kernel_mapped) {
792 /* $ORIGIN searches cannot be performed for the main program
793 * when it is suid/sgid/AT_SECURE. This is because the
794 * pathname is under the control of the caller of execve.
795 * For libraries, however, $ORIGIN can be processed safely
796 * since the library's pathname came from a trusted source
797 * (either system paths or a call to dlopen). */
798 if (libc.secure)
799 return 0;
800 l = readlink("/proc/self/exe", buf, buf_size);
801 if (l == -1) switch (errno) {
802 case ENOENT:
803 case ENOTDIR:
804 case EACCES:
805 break;
806 default:
807 return -1;
808 }
809 if (l >= buf_size)
810 return 0;
811 buf[l] = 0;
812 origin = buf;
813 } else {
814 origin = p->name;
815 }
816 t = strrchr(origin, '/');
817 l = t ? t-origin : 0;
818 p->rpath = malloc(strlen(p->rpath_orig) + n*l + 1);
819 if (!p->rpath) return -1;
820
821 d = p->rpath;
822 s = p->rpath_orig;
823 while ((t=strchr(s, '$'))) {
824 memcpy(d, s, t-s);
825 d += t-s;
826 memcpy(d, origin, l);
827 d += l;
828 /* It was determined previously that the '$' is followed
829 * either by "ORIGIN" or "{ORIGIN}". */
830 s = t + 7 + 2*(t[1]=='{');
831 }
832 strcpy(d, s);
833 return 0;
834}
835
836static void decode_dyn(struct dso *p)
837{
838 size_t dyn[DYN_CNT];
839 decode_vec(p->dynv, dyn, DYN_CNT);
840 p->syms = laddr(p, dyn[DT_SYMTAB]);
841 p->strings = laddr(p, dyn[DT_STRTAB]);
842 if (dyn[0]&(1<<DT_HASH))
843 p->hashtab = laddr(p, dyn[DT_HASH]);
844 if (dyn[0]&(1<<DT_RPATH))
845 p->rpath_orig = p->strings + dyn[DT_RPATH];
846 if (dyn[0]&(1<<DT_RUNPATH))
847 p->rpath_orig = p->strings + dyn[DT_RUNPATH];
848 if (dyn[0]&(1<<DT_PLTGOT))
849 p->got = laddr(p, dyn[DT_PLTGOT]);
850 if (search_vec(p->dynv, dyn, DT_GNU_HASH))
851 p->ghashtab = laddr(p, *dyn);
852 if (search_vec(p->dynv, dyn, DT_VERSYM))
853 p->versym = laddr(p, *dyn);
854}
855
856static size_t count_syms(struct dso *p)
857{
858 if (p->hashtab) return p->hashtab[1];
859
860 size_t nsym, i;
861 uint32_t *buckets = p->ghashtab + 4 + (p->ghashtab[2]*sizeof(size_t)/4);
862 uint32_t *hashval;
863 for (i = nsym = 0; i < p->ghashtab[0]; i++) {
864 if (buckets[i] > nsym)
865 nsym = buckets[i];
866 }
867 if (nsym) {
868 hashval = buckets + p->ghashtab[0] + (nsym - p->ghashtab[1]);
869 do nsym++;
870 while (!(*hashval++ & 1));
871 }
872 return nsym;
873}
874
875static void *dl_mmap(size_t n)
876{
877 void *p;
878 int prot = PROT_READ|PROT_WRITE, flags = MAP_ANONYMOUS|MAP_PRIVATE;
879#ifdef SYS_mmap2
880 p = (void *)__syscall(SYS_mmap2, 0, n, prot, flags, -1, 0);
881#else
882 p = (void *)__syscall(SYS_mmap, 0, n, prot, flags, -1, 0);
883#endif
884 return p == MAP_FAILED ? 0 : p;
885}
886
887static void makefuncdescs(struct dso *p)
888{
889 static int self_done;
890 size_t nsym = count_syms(p);
891 size_t i, size = nsym * sizeof(*p->funcdescs);
892
893 if (!self_done) {
894 p->funcdescs = dl_mmap(size);
895 self_done = 1;
896 } else {
897 p->funcdescs = malloc(size);
898 }
899 if (!p->funcdescs) {
900 if (!runtime) a_crash();
901 error("Error allocating function descriptors for %s", p->name);
902 longjmp(*rtld_fail, 1);
903 }
904 for (i=0; i<nsym; i++) {
905 if ((p->syms[i].st_info&0xf)==STT_FUNC && p->syms[i].st_shndx) {
906 p->funcdescs[i].addr = laddr(p, p->syms[i].st_value);
907 p->funcdescs[i].got = p->got;
908 } else {
909 p->funcdescs[i].addr = 0;
910 p->funcdescs[i].got = 0;
911 }
912 }
913}
914
915static struct dso *load_library(const char *name, struct dso *needed_by)
916{
917 char buf[2*NAME_MAX+2];
918 const char *pathname;
919 unsigned char *map;
920 struct dso *p, temp_dso = {0};
921 int fd;
922 struct stat st;
923 size_t alloc_size;
924 int n_th = 0;
925 int is_self = 0;
926
927 if (!*name) {
928 errno = EINVAL;
929 return 0;
930 }
931
932 /* Catch and block attempts to reload the implementation itself */
933 if (name[0]=='l' && name[1]=='i' && name[2]=='b') {
934 static const char reserved[] =
935 "c.pthread.rt.m.dl.util.xnet.";
936 const char *rp, *next;
937 for (rp=reserved; *rp; rp=next) {
938 next = strchr(rp, '.') + 1;
939 if (strncmp(name+3, rp, next-rp) == 0)
940 break;
941 }
942 if (*rp) {
943 if (ldd_mode) {
944 /* Track which names have been resolved
945 * and only report each one once. */
946 static unsigned reported;
947 unsigned mask = 1U<<(rp-reserved);
948 if (!(reported & mask)) {
949 reported |= mask;
950 dprintf(1, "\t%s => %s (%p)\n",
951 name, ldso.name,
952 ldso.base);
953 }
954 }
955 is_self = 1;
956 }
957 }
958 if (!strcmp(name, ldso.name)) is_self = 1;
959 if (is_self) {
960 if (!ldso.prev) {
961 tail->next = &ldso;
962 ldso.prev = tail;
963 tail = &ldso;
964 }
965 return &ldso;
966 }
967 if (strchr(name, '/')) {
968 pathname = name;
969 fd = open(name, O_RDONLY|O_CLOEXEC);
970 } else {
971 /* Search for the name to see if it's already loaded */
972 for (p=head->next; p; p=p->next) {
973 if (p->shortname && !strcmp(p->shortname, name)) {
974 return p;
975 }
976 }
977 if (strlen(name) > NAME_MAX) return 0;
978 fd = -1;
979 if (env_path) fd = path_open(name, env_path, buf, sizeof buf);
980 for (p=needed_by; fd == -1 && p; p=p->needed_by) {
981 if (fixup_rpath(p, buf, sizeof buf) < 0)
982 fd = -2; /* Inhibit further search. */
983 if (p->rpath)
984 fd = path_open(name, p->rpath, buf, sizeof buf);
985 }
986 if (fd == -1) {
987 if (!sys_path) {
988 char *prefix = 0;
989 size_t prefix_len;
990 if (ldso.name[0]=='/') {
991 char *s, *t, *z;
992 for (s=t=z=ldso.name; *s; s++)
993 if (*s=='/') z=t, t=s;
994 prefix_len = z-ldso.name;
995 if (prefix_len < PATH_MAX)
996 prefix = ldso.name;
997 }
998 if (!prefix) {
999 prefix = "";
1000 prefix_len = 0;
1001 }
1002 char etc_ldso_path[prefix_len + 1
1003 + sizeof "/etc/ld-musl-" LDSO_ARCH ".path"];
1004 snprintf(etc_ldso_path, sizeof etc_ldso_path,
1005 "%.*s/etc/ld-musl-" LDSO_ARCH ".path",
1006 (int)prefix_len, prefix);
1007 FILE *f = fopen(etc_ldso_path, "rbe");
1008 if (f) {
1009 if (getdelim(&sys_path, (size_t[1]){0}, 0, f) <= 0) {
1010 free(sys_path);
1011 sys_path = "";
1012 }
1013 fclose(f);
1014 } else if (errno != ENOENT) {
1015 sys_path = "";
1016 }
1017 }
1018 if (!sys_path) sys_path = "/lib:/usr/local/lib:/usr/lib";
1019 fd = path_open(name, sys_path, buf, sizeof buf);
1020 }
1021 pathname = buf;
1022 }
1023 if (fd < 0) return 0;
1024 if (fstat(fd, &st) < 0) {
1025 close(fd);
1026 return 0;
1027 }
1028 for (p=head->next; p; p=p->next) {
1029 if (p->dev == st.st_dev && p->ino == st.st_ino) {
1030 /* If this library was previously loaded with a
1031 * pathname but a search found the same inode,
1032 * setup its shortname so it can be found by name. */
1033 if (!p->shortname && pathname != name)
1034 p->shortname = strrchr(p->name, '/')+1;
1035 close(fd);
1036 return p;
1037 }
1038 }
1039 map = noload ? 0 : map_library(fd, &temp_dso);
1040 close(fd);
1041 if (!map) return 0;
1042
1043 /* Avoid the danger of getting two versions of libc mapped into the
1044 * same process when an absolute pathname was used. The symbols
1045 * checked are chosen to catch both musl and glibc, and to avoid
1046 * false positives from interposition-hack libraries. */
1047 decode_dyn(&temp_dso);
1048 if (find_sym(&temp_dso, "__libc_start_main", 1).sym &&
1049 find_sym(&temp_dso, "stdin", 1).sym) {
1050 unmap_library(&temp_dso);
1051 return load_library("libc.so", needed_by);
1052 }
1053
1054 /* Allocate storage for the new DSO. When there is TLS, this
1055 * storage must include a reservation for all pre-existing
1056 * threads to obtain copies of both the new TLS, and an
1057 * extended DTV capable of storing an additional slot for
1058 * the newly-loaded DSO. */
1059 alloc_size = sizeof *p + strlen(pathname) + 1;
1060 if (runtime && temp_dso.tls.image) {
1061 size_t per_th = temp_dso.tls.size + temp_dso.tls.align
1062 + sizeof(void *) * (tls_cnt+3);
1063 n_th = libc.threads_minus_1 + 1;
1064 if (n_th > SSIZE_MAX / per_th) alloc_size = SIZE_MAX;
1065 else alloc_size += n_th * per_th;
1066 }
1067 p = calloc(1, alloc_size);
1068 if (!p) {
1069 unmap_library(&temp_dso);
1070 return 0;
1071 }
1072 memcpy(p, &temp_dso, sizeof temp_dso);
1073 p->dev = st.st_dev;
1074 p->ino = st.st_ino;
1075 p->needed_by = needed_by;
1076 p->name = p->buf;
1077 strcpy(p->name, pathname);
1078 /* Add a shortname only if name arg was not an explicit pathname. */
1079 if (pathname != name) p->shortname = strrchr(p->name, '/')+1;
1080 if (p->tls.image) {
1081 p->tls_id = ++tls_cnt;
1082 tls_align = MAXP2(tls_align, p->tls.align);
1083#ifdef TLS_ABOVE_TP
1084 p->tls.offset = tls_offset + ( (tls_align-1) &
1085 -(tls_offset + (uintptr_t)p->tls.image) );
1086 tls_offset += p->tls.size;
1087#else
1088 tls_offset += p->tls.size + p->tls.align - 1;
1089 tls_offset -= (tls_offset + (uintptr_t)p->tls.image)
1090 & (p->tls.align-1);
1091 p->tls.offset = tls_offset;
1092#endif
1093 p->new_dtv = (void *)(-sizeof(size_t) &
1094 (uintptr_t)(p->name+strlen(p->name)+sizeof(size_t)));
1095 p->new_tls = (void *)(p->new_dtv + n_th*(tls_cnt+1));
1096 if (tls_tail) tls_tail->next = &p->tls;
1097 else libc.tls_head = &p->tls;
1098 tls_tail = &p->tls;
1099 }
1100
1101 tail->next = p;
1102 p->prev = tail;
1103 tail = p;
1104
1105 if (DL_FDPIC) makefuncdescs(p);
1106
1107 if (ldd_mode) dprintf(1, "\t%s => %s (%p)\n", name, pathname, p->base);
1108
1109 return p;
1110}
1111
1112static void load_deps(struct dso *p)
1113{
1114 size_t i, ndeps=0;
1115 struct dso ***deps = &p->deps, **tmp, *dep;
1116 for (; p; p=p->next) {
1117 for (i=0; p->dynv[i]; i+=2) {
1118 if (p->dynv[i] != DT_NEEDED) continue;
1119 dep = load_library(p->strings + p->dynv[i+1], p);
1120 if (!dep) {
1121 error("Error loading shared library %s: %m (needed by %s)",
1122 p->strings + p->dynv[i+1], p->name);
1123 if (runtime) longjmp(*rtld_fail, 1);
1124 continue;
1125 }
1126 if (runtime) {
1127 tmp = realloc(*deps, sizeof(*tmp)*(ndeps+2));
1128 if (!tmp) longjmp(*rtld_fail, 1);
1129 tmp[ndeps++] = dep;
1130 tmp[ndeps] = 0;
1131 *deps = tmp;
1132 }
1133 }
1134 }
1135 if (!*deps) *deps = (struct dso **)&nodeps_dummy;
1136}
1137
1138static void load_preload(char *s)
1139{
1140 int tmp;
1141 char *z;
1142 for (z=s; *z; s=z) {
1143 for ( ; *s && (isspace(*s) || *s==':'); s++);
1144 for (z=s; *z && !isspace(*z) && *z!=':'; z++);
1145 tmp = *z;
1146 *z = 0;
1147 load_library(s, 0);
1148 *z = tmp;
1149 }
1150}
1151
1152static void add_syms(struct dso *p)
1153{
1154 if (!p->syms_next && syms_tail != p) {
1155 syms_tail->syms_next = p;
1156 syms_tail = p;
1157 }
1158}
1159
1160static void revert_syms(struct dso *old_tail)
1161{
1162 struct dso *p, *next;
1163 /* Chop off the tail of the list of dsos that participate in
1164 * the global symbol table, reverting them to RTLD_LOCAL. */
1165 for (p=old_tail; p; p=next) {
1166 next = p->syms_next;
1167 p->syms_next = 0;
1168 }
1169 syms_tail = old_tail;
1170}
1171
1172static void do_mips_relocs(struct dso *p, size_t *got)
1173{
1174 size_t i, j, rel[2];
1175 unsigned char *base = p->base;
1176 i=0; search_vec(p->dynv, &i, DT_MIPS_LOCAL_GOTNO);
1177 if (p==&ldso) {
1178 got += i;
1179 } else {
1180 while (i--) *got++ += (size_t)base;
1181 }
1182 j=0; search_vec(p->dynv, &j, DT_MIPS_GOTSYM);
1183 i=0; search_vec(p->dynv, &i, DT_MIPS_SYMTABNO);
1184 Sym *sym = p->syms + j;
1185 rel[0] = (unsigned char *)got - base;
1186 for (i-=j; i; i--, sym++, rel[0]+=sizeof(size_t)) {
1187 rel[1] = R_INFO(sym-p->syms, R_MIPS_JUMP_SLOT);
1188 do_relocs(p, rel, sizeof rel, 2);
1189 }
1190}
1191
1192static void reloc_all(struct dso *p)
1193{
1194 size_t dyn[DYN_CNT];
1195 for (; p; p=p->next) {
1196 if (p->relocated) continue;
1197 decode_vec(p->dynv, dyn, DYN_CNT);
1198 if (NEED_MIPS_GOT_RELOCS)
1199 do_mips_relocs(p, laddr(p, dyn[DT_PLTGOT]));
1200 do_relocs(p, laddr(p, dyn[DT_JMPREL]), dyn[DT_PLTRELSZ],
1201 2+(dyn[DT_PLTREL]==DT_RELA));
1202 do_relocs(p, laddr(p, dyn[DT_REL]), dyn[DT_RELSZ], 2);
1203 do_relocs(p, laddr(p, dyn[DT_RELA]), dyn[DT_RELASZ], 3);
1204
1205 if (head != &ldso && p->relro_start != p->relro_end &&
1206 mprotect(laddr(p, p->relro_start), p->relro_end-p->relro_start, PROT_READ)
1207 && errno != ENOSYS) {
1208 error("Error relocating %s: RELRO protection failed: %m",
1209 p->name);
1210 if (runtime) longjmp(*rtld_fail, 1);
1211 }
1212
1213 p->relocated = 1;
1214 }
1215}
1216
1217static void kernel_mapped_dso(struct dso *p)
1218{
1219 size_t min_addr = -1, max_addr = 0, cnt;
1220 Phdr *ph = p->phdr;
1221 for (cnt = p->phnum; cnt--; ph = (void *)((char *)ph + p->phentsize)) {
1222 if (ph->p_type == PT_DYNAMIC) {
1223 p->dynv = laddr(p, ph->p_vaddr);
1224 } else if (ph->p_type == PT_GNU_RELRO) {
1225 p->relro_start = ph->p_vaddr & -PAGE_SIZE;
1226 p->relro_end = (ph->p_vaddr + ph->p_memsz) & -PAGE_SIZE;
1227 }
1228 if (ph->p_type != PT_LOAD) continue;
1229 if (ph->p_vaddr < min_addr)
1230 min_addr = ph->p_vaddr;
1231 if (ph->p_vaddr+ph->p_memsz > max_addr)
1232 max_addr = ph->p_vaddr+ph->p_memsz;
1233 }
1234 min_addr &= -PAGE_SIZE;
1235 max_addr = (max_addr + PAGE_SIZE-1) & -PAGE_SIZE;
1236 p->map = p->base + min_addr;
1237 p->map_len = max_addr - min_addr;
1238 p->kernel_mapped = 1;
1239}
1240
1241void __libc_exit_fini()
1242{
1243 struct dso *p;
1244 size_t dyn[DYN_CNT];
1245 for (p=fini_head; p; p=p->fini_next) {
1246 if (!p->constructed) continue;
1247 decode_vec(p->dynv, dyn, DYN_CNT);
1248 if (dyn[0] & (1<<DT_FINI_ARRAY)) {
1249 size_t n = dyn[DT_FINI_ARRAYSZ]/sizeof(size_t);
1250 size_t *fn = (size_t *)laddr(p, dyn[DT_FINI_ARRAY])+n;
1251 while (n--) ((void (*)(void))*--fn)();
1252 }
1253#ifndef NO_LEGACY_INITFINI
1254 if ((dyn[0] & (1<<DT_FINI)) && dyn[DT_FINI])
1255 fpaddr(p, dyn[DT_FINI])();
1256#endif
1257 }
1258}
1259
1260static void do_init_fini(struct dso *p)
1261{
1262 size_t dyn[DYN_CNT];
1263 int need_locking = libc.threads_minus_1;
1264 /* Allow recursive calls that arise when a library calls
1265 * dlopen from one of its constructors, but block any
1266 * other threads until all ctors have finished. */
1267 if (need_locking) pthread_mutex_lock(&init_fini_lock);
1268 for (; p; p=p->prev) {
1269 if (p->constructed) continue;
1270 p->constructed = 1;
1271 decode_vec(p->dynv, dyn, DYN_CNT);
1272 if (dyn[0] & ((1<<DT_FINI) | (1<<DT_FINI_ARRAY))) {
1273 p->fini_next = fini_head;
1274 fini_head = p;
1275 }
1276#ifndef NO_LEGACY_INITFINI
1277 if ((dyn[0] & (1<<DT_INIT)) && dyn[DT_INIT])
1278 fpaddr(p, dyn[DT_INIT])();
1279#endif
1280 if (dyn[0] & (1<<DT_INIT_ARRAY)) {
1281 size_t n = dyn[DT_INIT_ARRAYSZ]/sizeof(size_t);
1282 size_t *fn = laddr(p, dyn[DT_INIT_ARRAY]);
1283 while (n--) ((void (*)(void))*fn++)();
1284 }
1285 if (!need_locking && libc.threads_minus_1) {
1286 need_locking = 1;
1287 pthread_mutex_lock(&init_fini_lock);
1288 }
1289 }
1290 if (need_locking) pthread_mutex_unlock(&init_fini_lock);
1291}
1292
1293#ifndef __c2__
1294void __libc_start_init(void)
1295{
1296 do_init_fini(tail);
1297}
1298#endif
1299
1300static void dl_debug_state(void)
1301{
1302}
1303
1304#ifndef __c2__
1305weak_alias(dl_debug_state, _dl_debug_state);
1306
1307void __init_tls(size_t *auxv)
1308{
1309}
1310#else
1311__attribute__((weak))
1312void _dl_debug_state(void)
1313{
1314 dl_debug_state();
1315}
1316#endif
1317
1318__attribute__((__visibility__("hidden")))
1319void *__tls_get_new(tls_mod_off_t *v)
1320{
1321 pthread_t self = __pthread_self();
1322
1323 /* Block signals to make accessing new TLS async-signal-safe */
1324 sigset_t set;
1325 __block_all_sigs(&set);
1326 if (v[0]<=(size_t)self->dtv[0]) {
1327 __restore_sigs(&set);
1328 return (char *)self->dtv[v[0]]+v[1]+DTP_OFFSET;
1329 }
1330
1331 /* This is safe without any locks held because, if the caller
1332 * is able to request the Nth entry of the DTV, the DSO list
1333 * must be valid at least that far out and it was synchronized
1334 * at program startup or by an already-completed call to dlopen. */
1335 struct dso *p;
1336 for (p=head; p->tls_id != v[0]; p=p->next);
1337
1338 /* Get new DTV space from new DSO if needed */
1339 if (v[0] > (size_t)self->dtv[0]) {
1340 void **newdtv = p->new_dtv +
1341 (v[0]+1)*a_fetch_add(&p->new_dtv_idx,1);
1342 memcpy(newdtv, self->dtv,
1343 ((size_t)self->dtv[0]+1) * sizeof(void *));
1344 newdtv[0] = (void *)v[0];
1345 self->dtv = self->dtv_copy = newdtv;
1346 }
1347
1348 /* Get new TLS memory from all new DSOs up to the requested one */
1349 unsigned char *mem;
1350 for (p=head; ; p=p->next) {
1351 if (!p->tls_id || self->dtv[p->tls_id]) continue;
1352 mem = p->new_tls + (p->tls.size + p->tls.align)
1353 * a_fetch_add(&p->new_tls_idx,1);
1354 mem += ((uintptr_t)p->tls.image - (uintptr_t)mem)
1355 & (p->tls.align-1);
1356 self->dtv[p->tls_id] = mem;
1357 memcpy(mem, p->tls.image, p->tls.len);
1358 if (p->tls_id == v[0]) break;
1359 }
1360 __restore_sigs(&set);
1361 return mem + v[1] + DTP_OFFSET;
1362}
1363
1364static void update_tls_size()
1365{
1366 libc.tls_cnt = tls_cnt;
1367 libc.tls_align = tls_align;
1368 libc.tls_size = ALIGN(
1369 (1+tls_cnt) * sizeof(void *) +
1370 tls_offset +
1371 sizeof(struct pthread) +
1372 tls_align * 2,
1373 tls_align);
1374}
1375
1376/* Stage 1 of the dynamic linker is defined in dlstart.c. It calls the
1377 * following stage 2 and stage 3 functions via primitive symbolic lookup
1378 * since it does not have access to their addresses to begin with. */
1379
1380/* Stage 2 of the dynamic linker is called after relative relocations
1381 * have been processed. It can make function calls to static functions
1382 * and access string literals and static data, but cannot use extern
1383 * symbols. Its job is to perform symbolic relocations on the dynamic
1384 * linker itself, but some of the relocations performed may need to be
1385 * replaced later due to copy relocations in the main program. */
1386
1387__attribute__((__visibility__("hidden")))
1388void __dls2(unsigned char *base, size_t *sp)
1389{
1390 if (DL_FDPIC) {
1391 void *p1 = (void *)sp[-2];
1392 void *p2 = (void *)sp[-1];
1393 if (!p1) {
1394 size_t *auxv, aux[AUX_CNT];
1395 for (auxv=sp+1+*sp+1; *auxv; auxv++); auxv++;
1396 decode_vec(auxv, aux, AUX_CNT);
1397 if (aux[AT_BASE]) ldso.base = (void *)aux[AT_BASE];
1398 else ldso.base = (void *)(aux[AT_PHDR] & -4096);
1399 }
1400 app_loadmap = p2 ? p1 : 0;
1401 ldso.loadmap = p2 ? p2 : p1;
1402 ldso.base = laddr(&ldso, 0);
1403 } else {
1404 ldso.base = base;
1405 }
1406 Ehdr *ehdr = (void *)ldso.base;
1407 ldso.name = ldso.shortname = "libc.so";
1408 ldso.phnum = ehdr->e_phnum;
1409 ldso.phdr = laddr(&ldso, ehdr->e_phoff);
1410 ldso.phentsize = ehdr->e_phentsize;
1411 kernel_mapped_dso(&ldso);
1412 decode_dyn(&ldso);
1413
1414 if (DL_FDPIC) makefuncdescs(&ldso);
1415
1416 /* Prepare storage for to save clobbered REL addends so they
1417 * can be reused in stage 3. There should be very few. If
1418 * something goes wrong and there are a huge number, abort
1419 * instead of risking stack overflow. */
1420 size_t dyn[DYN_CNT];
1421 decode_vec(ldso.dynv, dyn, DYN_CNT);
1422 size_t *rel = laddr(&ldso, dyn[DT_REL]);
1423 size_t rel_size = dyn[DT_RELSZ];
1424 size_t symbolic_rel_cnt = 0;
1425 apply_addends_to = rel;
1426 for (; rel_size; rel+=2, rel_size-=2*sizeof(size_t))
1427 if (!IS_RELATIVE(rel[1], ldso.syms)) symbolic_rel_cnt++;
1428 if (symbolic_rel_cnt >= ADDEND_LIMIT) a_crash();
1429 size_t addends[symbolic_rel_cnt+1];
1430 saved_addends = addends;
1431
1432 head = &ldso;
1433 reloc_all(&ldso);
1434
1435 ldso.relocated = 0;
1436
1437 /* Call dynamic linker stage-3, __dls3, looking it up
1438 * symbolically as a barrier against moving the address
1439 * load across the above relocation processing. */
1440 struct symdef dls3_def = find_sym(&ldso, "__dls3", 0);
1441 if (DL_FDPIC) ((stage3_func)&ldso.funcdescs[dls3_def.sym-ldso.syms])(sp);
1442 else ((stage3_func)laddr(&ldso, dls3_def.sym->st_value))(sp);
1443}
1444
1445/* Stage 3 of the dynamic linker is called with the dynamic linker/libc
1446 * fully functional. Its job is to load (if not already loaded) and
1447 * process dependencies and relocations for the main application and
1448 * transfer control to its entry point. */
1449
1450_Noreturn void __dls3(size_t *sp)
1451{
1452 static struct dso app, vdso;
1453 size_t aux[AUX_CNT], *auxv;
1454 size_t i;
1455 char *env_preload=0;
1456 char *replace_argv0=0;
1457 size_t vdso_base;
1458 int argc = *sp;
1459 char **argv = (void *)(sp+1);
1460 char **argv_orig = argv;
1461 char **envp = argv+argc+1;
1462
1463 /* Find aux vector just past environ[] and use it to initialize
1464 * global data that may be needed before we can make syscalls. */
1465 __environ = envp;
1466 for (i=argc+1; argv[i]; i++);
1467 libc.auxv = auxv = (void *)(argv+i+1);
1468 decode_vec(auxv, aux, AUX_CNT);
1469 __hwcap = aux[AT_HWCAP];
1470 libc.page_size = aux[AT_PAGESZ];
1471 libc.secure = ((aux[0]&0x7800)!=0x7800 || aux[AT_UID]!=aux[AT_EUID]
1472 || aux[AT_GID]!=aux[AT_EGID] || aux[AT_SECURE]);
1473
1474 /* Setup early thread pointer in builtin_tls for ldso/libc itself to
1475 * use during dynamic linking. If possible it will also serve as the
1476 * thread pointer at runtime. */
1477 libc.tls_size = sizeof builtin_tls;
1478 libc.tls_align = tls_align;
1479 if (__init_tp(__copy_tls((void *)builtin_tls)) < 0) {
1480 a_crash();
1481 }
1482
1483 /* Only trust user/env if kernel says we're not suid/sgid */
1484 if (!libc.secure) {
1485 env_path = getenv("LD_LIBRARY_PATH");
1486 env_preload = getenv("LD_PRELOAD");
1487 }
1488
1489 /* If the main program was already loaded by the kernel,
1490 * AT_PHDR will point to some location other than the dynamic
1491 * linker's program headers. */
1492 if (aux[AT_PHDR] != (size_t)ldso.phdr) {
1493 size_t interp_off = 0;
1494 size_t tls_image = 0;
1495 /* Find load address of the main program, via AT_PHDR vs PT_PHDR. */
1496 Phdr *phdr = app.phdr = (void *)aux[AT_PHDR];
1497 app.phnum = aux[AT_PHNUM];
1498 app.phentsize = aux[AT_PHENT];
1499 for (i=aux[AT_PHNUM]; i; i--, phdr=(void *)((char *)phdr + aux[AT_PHENT])) {
1500 if (phdr->p_type == PT_PHDR)
1501 app.base = (void *)(aux[AT_PHDR] - phdr->p_vaddr);
1502 else if (phdr->p_type == PT_INTERP)
1503 interp_off = (size_t)phdr->p_vaddr;
1504 else if (phdr->p_type == PT_TLS) {
1505 tls_image = phdr->p_vaddr;
1506 app.tls.len = phdr->p_filesz;
1507 app.tls.size = phdr->p_memsz;
1508 app.tls.align = phdr->p_align;
1509 }
1510 }
1511 if (DL_FDPIC) app.loadmap = app_loadmap;
1512 if (app.tls.size) app.tls.image = laddr(&app, tls_image);
1513 if (interp_off) ldso.name = laddr(&app, interp_off);
1514 if ((aux[0] & (1UL<<AT_EXECFN))
1515 && strncmp((char *)aux[AT_EXECFN], "/proc/", 6))
1516 app.name = (char *)aux[AT_EXECFN];
1517 else
1518 app.name = argv[0];
1519 kernel_mapped_dso(&app);
1520 } else {
1521 int fd;
1522 char *ldname = argv[0];
1523 size_t l = strlen(ldname);
1524 if (l >= 3 && !strcmp(ldname+l-3, "ldd")) ldd_mode = 1;
1525 argv++;
1526 while (argv[0] && argv[0][0]=='-' && argv[0][1]=='-') {
1527 char *opt = argv[0]+2;
1528 *argv++ = (void *)-1;
1529 if (!*opt) {
1530 break;
1531 } else if (!memcmp(opt, "list", 5)) {
1532 ldd_mode = 1;
1533 } else if (!memcmp(opt, "library-path", 12)) {
1534 if (opt[12]=='=') env_path = opt+13;
1535 else if (opt[12]) *argv = 0;
1536 else if (*argv) env_path = *argv++;
1537 } else if (!memcmp(opt, "preload", 7)) {
1538 if (opt[7]=='=') env_preload = opt+8;
1539 else if (opt[7]) *argv = 0;
1540 else if (*argv) env_preload = *argv++;
1541 } else if (!memcmp(opt, "argv0", 5)) {
1542 if (opt[5]=='=') replace_argv0 = opt+6;
1543 else if (opt[5]) *argv = 0;
1544 else if (*argv) replace_argv0 = *argv++;
1545 } else {
1546 argv[0] = 0;
1547 }
1548 }
1549 argv[-1] = (void *)(argc - (argv-argv_orig));
1550 if (!argv[0]) {
1551 dprintf(2, "musl libc (" LDSO_ARCH ")\n"
1552 "Version %s\n"
1553 "Dynamic Program Loader\n"
1554 "Usage: %s [options] [--] pathname%s\n",
1555 __libc_get_version(), ldname,
1556 ldd_mode ? "" : " [args]");
1557 _exit(1);
1558 }
1559 fd = open(argv[0], O_RDONLY);
1560 if (fd < 0) {
1561 dprintf(2, "%s: cannot load %s: %s\n", ldname, argv[0], strerror(errno));
1562 _exit(1);
1563 }
1564 runtime = 1;
1565 Ehdr *ehdr = (void *)map_library(fd, &app);
1566 if (!ehdr) {
1567 dprintf(2, "%s: %s: Not a valid dynamic program\n", ldname, argv[0]);
1568 _exit(1);
1569 }
1570 runtime = 0;
1571 close(fd);
1572 ldso.name = ldname;
1573 app.name = argv[0];
1574 aux[AT_ENTRY] = (size_t)laddr(&app, ehdr->e_entry);
1575 /* Find the name that would have been used for the dynamic
1576 * linker had ldd not taken its place. */
1577 if (ldd_mode) {
1578 for (i=0; i<app.phnum; i++) {
1579 if (app.phdr[i].p_type == PT_INTERP)
1580 ldso.name = laddr(&app, app.phdr[i].p_vaddr);
1581 }
1582 dprintf(1, "\t%s (%p)\n", ldso.name, ldso.base);
1583 }
1584 }
1585 if (app.tls.size) {
1586 libc.tls_head = tls_tail = &app.tls;
1587 app.tls_id = tls_cnt = 1;
1588#ifdef TLS_ABOVE_TP
1589 app.tls.offset = 0;
1590 tls_offset = app.tls.size
1591 + ( -((uintptr_t)app.tls.image + app.tls.size)
1592 & (app.tls.align-1) );
1593#else
1594 tls_offset = app.tls.offset = app.tls.size
1595 + ( -((uintptr_t)app.tls.image + app.tls.size)
1596 & (app.tls.align-1) );
1597#endif
1598 tls_align = MAXP2(tls_align, app.tls.align);
1599 }
1600 decode_dyn(&app);
1601 if (DL_FDPIC) {
1602 makefuncdescs(&app);
1603 if (!app.loadmap) {
1604 app.loadmap = (void *)&app_dummy_loadmap;
1605 app.loadmap->nsegs = 1;
1606 app.loadmap->segs[0].addr = (size_t)app.map;
1607 app.loadmap->segs[0].p_vaddr = (size_t)app.map
1608 - (size_t)app.base;
1609 app.loadmap->segs[0].p_memsz = app.map_len;
1610 }
1611 argv[-3] = (void *)app.loadmap;
1612 }
1613
1614 /* Initial dso chain consists only of the app. */
1615 head = tail = syms_tail = &app;
1616
1617 /* Donate unused parts of app and library mapping to malloc */
1618 reclaim_gaps(&app);
1619 reclaim_gaps(&ldso);
1620
1621 /* Load preload/needed libraries, add symbols to global namespace. */
1622 if (env_preload) load_preload(env_preload);
1623 load_deps(&app);
1624 for (struct dso *p=head; p; p=p->next)
1625 add_syms(p);
1626
1627 /* Attach to vdso, if provided by the kernel, last so that it does
1628 * not become part of the global namespace. */
1629 if (search_vec(auxv, &vdso_base, AT_SYSINFO_EHDR) && vdso_base) {
1630 Ehdr *ehdr = (void *)vdso_base;
1631 Phdr *phdr = vdso.phdr = (void *)(vdso_base + ehdr->e_phoff);
1632 vdso.phnum = ehdr->e_phnum;
1633 vdso.phentsize = ehdr->e_phentsize;
1634 for (i=ehdr->e_phnum; i; i--, phdr=(void *)((char *)phdr + ehdr->e_phentsize)) {
1635 if (phdr->p_type == PT_DYNAMIC)
1636 vdso.dynv = (void *)(vdso_base + phdr->p_offset);
1637 if (phdr->p_type == PT_LOAD)
1638 vdso.base = (void *)(vdso_base - phdr->p_vaddr + phdr->p_offset);
1639 }
1640 vdso.name = "";
1641 vdso.shortname = "linux-gate.so.1";
1642 vdso.relocated = 1;
1643 decode_dyn(&vdso);
1644 vdso.prev = tail;
1645 tail->next = &vdso;
1646 tail = &vdso;
1647 }
1648
1649 for (i=0; app.dynv[i]; i+=2) {
1650 if (!DT_DEBUG_INDIRECT && app.dynv[i]==DT_DEBUG)
1651 app.dynv[i+1] = (size_t)&debug;
1652 if (DT_DEBUG_INDIRECT && app.dynv[i]==DT_DEBUG_INDIRECT) {
1653 size_t *ptr = (size_t *) app.dynv[i+1];
1654 *ptr = (size_t)&debug;
1655 }
1656 }
1657
1658 /* The main program must be relocated LAST since it may contin
1659 * copy relocations which depend on libraries' relocations. */
1660 reloc_all(app.next);
1661 reloc_all(&app);
1662
1663 update_tls_size();
1664 if (libc.tls_size > sizeof builtin_tls || tls_align > MIN_TLS_ALIGN) {
1665 void *initial_tls = calloc(libc.tls_size, 1);
1666 if (!initial_tls) {
1667 dprintf(2, "%s: Error getting %zu bytes thread-local storage: %m\n",
1668 argv[0], libc.tls_size);
1669 _exit(127);
1670 }
1671 if (__init_tp(__copy_tls(initial_tls)) < 0) {
1672 a_crash();
1673 }
1674 } else {
1675 size_t tmp_tls_size = libc.tls_size;
1676 pthread_t self = __pthread_self();
1677 /* Temporarily set the tls size to the full size of
1678 * builtin_tls so that __copy_tls will use the same layout
1679 * as it did for before. Then check, just to be safe. */
1680 libc.tls_size = sizeof builtin_tls;
1681 if (__copy_tls((void*)builtin_tls) != self) a_crash();
1682 libc.tls_size = tmp_tls_size;
1683 }
1684 static_tls_cnt = tls_cnt;
1685
1686 if (ldso_fail) _exit(127);
1687 if (ldd_mode) _exit(0);
1688
1689 /* Switch to runtime mode: any further failures in the dynamic
1690 * linker are a reportable failure rather than a fatal startup
1691 * error. */
1692 runtime = 1;
1693
1694 debug.ver = 1;
1695 debug.bp = dl_debug_state;
1696 debug.head = head;
1697 debug.base = ldso.base;
1698 debug.state = 0;
1699 _dl_debug_state();
1700
1701 if (replace_argv0) argv[0] = replace_argv0;
1702
1703 errno = 0;
1704
1705 CRTJMP((void *)aux[AT_ENTRY], argv-1);
1706 for(;;);
1707}
1708
1709static void prepare_lazy(struct dso *p)
1710{
1711 size_t dyn[DYN_CNT], n, flags1=0;
1712 decode_vec(p->dynv, dyn, DYN_CNT);
1713 search_vec(p->dynv, &flags1, DT_FLAGS_1);
1714 if (dyn[DT_BIND_NOW] || (dyn[DT_FLAGS] & DF_BIND_NOW) || (flags1 & DF_1_NOW))
1715 return;
1716 n = dyn[DT_RELSZ]/2 + dyn[DT_RELASZ]/3 + dyn[DT_PLTRELSZ]/2 + 1;
1717 if (NEED_MIPS_GOT_RELOCS) {
1718 size_t j=0; search_vec(p->dynv, &j, DT_MIPS_GOTSYM);
1719 size_t i=0; search_vec(p->dynv, &i, DT_MIPS_SYMTABNO);
1720 n += i-j;
1721 }
1722 p->lazy = calloc(n, 3*sizeof(size_t));
1723 if (!p->lazy) {
1724 error("Error preparing lazy relocation for %s: %m", p->name);
1725 longjmp(*rtld_fail, 1);
1726 }
1727 p->lazy_next = lazy_head;
1728 lazy_head = p;
1729}
1730
1731void *dlopen(const char *file, int mode)
1732{
1733 struct dso *volatile p, *orig_tail, *orig_syms_tail, *orig_lazy_head, *next;
1734 struct tls_module *orig_tls_tail;
1735 size_t orig_tls_cnt, orig_tls_offset, orig_tls_align;
1736 size_t i;
1737 int cs;
1738 jmp_buf jb;
1739
1740 if (!file) return head;
1741
1742 pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
1743 pthread_rwlock_wrlock(&lock);
1744 __inhibit_ptc();
1745
1746 p = 0;
1747 orig_tls_tail = tls_tail;
1748 orig_tls_cnt = tls_cnt;
1749 orig_tls_offset = tls_offset;
1750 orig_tls_align = tls_align;
1751 orig_lazy_head = lazy_head;
1752 orig_syms_tail = syms_tail;
1753 orig_tail = tail;
1754 noload = mode & RTLD_NOLOAD;
1755
1756 rtld_fail = &jb;
1757 if (setjmp(*rtld_fail)) {
1758 /* Clean up anything new that was (partially) loaded */
1759 revert_syms(orig_syms_tail);
1760 for (p=orig_tail->next; p; p=next) {
1761 next = p->next;
1762 while (p->td_index) {
1763 void *tmp = p->td_index->next;
1764 free(p->td_index);
1765 p->td_index = tmp;
1766 }
1767 free(p->funcdescs);
1768 if (p->rpath != p->rpath_orig)
1769 free(p->rpath);
1770 if (p->deps != &nodeps_dummy)
1771 free(p->deps);
1772 unmap_library(p);
1773 free(p);
1774 }
1775 if (!orig_tls_tail) libc.tls_head = 0;
1776 tls_tail = orig_tls_tail;
1777 if (tls_tail) tls_tail->next = 0;
1778 tls_cnt = orig_tls_cnt;
1779 tls_offset = orig_tls_offset;
1780 tls_align = orig_tls_align;
1781 lazy_head = orig_lazy_head;
1782 tail = orig_tail;
1783 tail->next = 0;
1784 p = 0;
1785 goto end;
1786 } else p = load_library(file, head);
1787
1788 if (!p) {
1789 error(noload ?
1790 "Library %s is not already loaded" :
1791 "Error loading shared library %s: %m",
1792 file);
1793 goto end;
1794 }
1795
1796 /* First load handling */
1797 int first_load = !p->deps;
1798 if (first_load) {
1799 load_deps(p);
1800 if (!p->relocated && (mode & RTLD_LAZY)) {
1801 prepare_lazy(p);
1802 for (i=0; p->deps[i]; i++)
1803 if (!p->deps[i]->relocated)
1804 prepare_lazy(p->deps[i]);
1805 }
1806 }
1807 if (first_load || (mode & RTLD_GLOBAL)) {
1808 /* Make new symbols global, at least temporarily, so we can do
1809 * relocations. If not RTLD_GLOBAL, this is reverted below. */
1810 add_syms(p);
1811 for (i=0; p->deps[i]; i++)
1812 add_syms(p->deps[i]);
1813 }
1814 if (first_load) {
1815 reloc_all(p);
1816 }
1817
1818 /* If RTLD_GLOBAL was not specified, undo any new additions
1819 * to the global symbol table. This is a nop if the library was
1820 * previously loaded and already global. */
1821 if (!(mode & RTLD_GLOBAL))
1822 revert_syms(orig_syms_tail);
1823
1824 /* Processing of deferred lazy relocations must not happen until
1825 * the new libraries are committed; otherwise we could end up with
1826 * relocations resolved to symbol definitions that get removed. */
1827 redo_lazy_relocs();
1828
1829 update_tls_size();
1830 _dl_debug_state();
1831 orig_tail = tail;
1832end:
1833 __release_ptc();
1834 if (p) gencnt++;
1835 pthread_rwlock_unlock(&lock);
1836 if (p) do_init_fini(orig_tail);
1837 pthread_setcancelstate(cs, 0);
1838 return p;
1839}
1840
1841__attribute__((__visibility__("hidden")))
1842int __dl_invalid_handle(void *h)
1843{
1844 struct dso *p;
1845 for (p=head; p; p=p->next) if (h==p) return 0;
1846 error("Invalid library handle %p", (void *)h);
1847 return 1;
1848}
1849
1850static void *addr2dso(size_t a)
1851{
1852 struct dso *p;
1853 size_t i;
1854 if (DL_FDPIC) for (p=head; p; p=p->next) {
1855 i = count_syms(p);
1856 if (a-(size_t)p->funcdescs < i*sizeof(*p->funcdescs))
1857 return p;
1858 }
1859 for (p=head; p; p=p->next) {
1860 if (DL_FDPIC && p->loadmap) {
1861 for (i=0; i<p->loadmap->nsegs; i++) {
1862 if (a-p->loadmap->segs[i].p_vaddr
1863 < p->loadmap->segs[i].p_memsz)
1864 return p;
1865 }
1866 } else {
1867 if (a-(size_t)p->map < p->map_len)
1868 return p;
1869 }
1870 }
1871 return 0;
1872}
1873
1874void *__tls_get_addr(tls_mod_off_t *);
1875
1876static void *do_dlsym(struct dso *p, const char *s, void *ra)
1877{
1878 size_t i;
1879 uint32_t h = 0, gh = 0, *ght;
1880 Sym *sym;
1881 if (p == head || p == RTLD_DEFAULT || p == RTLD_NEXT) {
1882 if (p == RTLD_DEFAULT) {
1883 p = head;
1884 } else if (p == RTLD_NEXT) {
1885 p = addr2dso((size_t)ra);
1886 if (!p) p=head;
1887 p = p->next;
1888 }
1889 struct symdef def = find_sym(p, s, 0);
1890 if (!def.sym) goto failed;
1891 if ((def.sym->st_info&0xf) == STT_TLS)
1892 return __tls_get_addr((tls_mod_off_t []){def.dso->tls_id, def.sym->st_value});
1893 if (DL_FDPIC && (def.sym->st_info&0xf) == STT_FUNC)
1894 return def.dso->funcdescs + (def.sym - def.dso->syms);
1895 return laddr(def.dso, def.sym->st_value);
1896 }
1897 if (__dl_invalid_handle(p))
1898 return 0;
1899 if ((ght = p->ghashtab)) {
1900 gh = gnu_hash(s);
1901 sym = gnu_lookup(gh, ght, p, s);
1902 } else {
1903 h = sysv_hash(s);
1904 sym = sysv_lookup(s, h, p);
1905 }
1906 if (sym && (sym->st_info&0xf) == STT_TLS)
1907 return __tls_get_addr((tls_mod_off_t []){p->tls_id, sym->st_value});
1908 if (DL_FDPIC && sym && sym->st_shndx && (sym->st_info&0xf) == STT_FUNC)
1909 return p->funcdescs + (sym - p->syms);
1910 if (sym && sym->st_value && (1<<(sym->st_info&0xf) & OK_TYPES))
1911 return laddr(p, sym->st_value);
1912 for (i=0; p->deps[i]; i++) {
1913 if ((ght = p->deps[i]->ghashtab)) {
1914 if (!gh) gh = gnu_hash(s);
1915 sym = gnu_lookup(gh, ght, p->deps[i], s);
1916 } else {
1917 if (!h) h = sysv_hash(s);
1918 sym = sysv_lookup(s, h, p->deps[i]);
1919 }
1920 if (sym && (sym->st_info&0xf) == STT_TLS)
1921 return __tls_get_addr((tls_mod_off_t []){p->deps[i]->tls_id, sym->st_value});
1922 if (DL_FDPIC && sym && sym->st_shndx && (sym->st_info&0xf) == STT_FUNC)
1923 return p->deps[i]->funcdescs + (sym - p->deps[i]->syms);
1924 if (sym && sym->st_value && (1<<(sym->st_info&0xf) & OK_TYPES))
1925 return laddr(p->deps[i], sym->st_value);
1926 }
1927failed:
1928 error("Symbol not found: %s", s);
1929 return 0;
1930}
1931
1932int dladdr(const void *addr, Dl_info *info)
1933{
1934 struct dso *p;
1935 Sym *sym, *bestsym;
1936 uint32_t nsym;
1937 char *strings;
1938 void *best = 0;
1939
1940 pthread_rwlock_rdlock(&lock);
1941 p = addr2dso((size_t)addr);
1942 pthread_rwlock_unlock(&lock);
1943
1944 if (!p) return 0;
1945
1946 sym = p->syms;
1947 strings = p->strings;
1948 nsym = count_syms(p);
1949
1950 if (DL_FDPIC) {
1951 size_t idx = ((size_t)addr-(size_t)p->funcdescs)
1952 / sizeof(*p->funcdescs);
1953 if (idx < nsym && (sym[idx].st_info&0xf) == STT_FUNC) {
1954 best = p->funcdescs + idx;
1955 bestsym = sym + idx;
1956 }
1957 }
1958
1959 if (!best) for (; nsym; nsym--, sym++) {
1960 if (sym->st_value
1961 && (1<<(sym->st_info&0xf) & OK_TYPES)
1962 && (1<<(sym->st_info>>4) & OK_BINDS)) {
1963 void *symaddr = laddr(p, sym->st_value);
1964 if (symaddr > addr || symaddr < best)
1965 continue;
1966 best = symaddr;
1967 bestsym = sym;
1968 if (addr == symaddr)
1969 break;
1970 }
1971 }
1972
1973 if (!best) return 0;
1974
1975 if (DL_FDPIC && (bestsym->st_info&0xf) == STT_FUNC)
1976 best = p->funcdescs + (bestsym - p->syms);
1977
1978 info->dli_fname = p->name;
1979 info->dli_fbase = p->base;
1980 info->dli_sname = strings + bestsym->st_name;
1981 info->dli_saddr = best;
1982
1983 return 1;
1984}
1985
1986__attribute__((__visibility__("hidden")))
1987void *__dlsym(void *restrict p, const char *restrict s, void *restrict ra)
1988{
1989 void *res;
1990 pthread_rwlock_rdlock(&lock);
1991 res = do_dlsym(p, s, ra);
1992 pthread_rwlock_unlock(&lock);
1993 return res;
1994}
1995
1996int dl_iterate_phdr(int(*callback)(struct dl_phdr_info *info, size_t size, void *data), void *data)
1997{
1998 struct dso *current;
1999 struct dl_phdr_info info;
2000 int ret = 0;
2001 for(current = head; current;) {
2002 info.dlpi_addr = (uintptr_t)current->base;
2003 info.dlpi_name = current->name;
2004 info.dlpi_phdr = current->phdr;
2005 info.dlpi_phnum = current->phnum;
2006 info.dlpi_adds = gencnt;
2007 info.dlpi_subs = 0;
2008 info.dlpi_tls_modid = current->tls_id;
2009 info.dlpi_tls_data = current->tls.image;
2010
2011 ret = (callback)(&info, sizeof (info), data);
2012
2013 if (ret != 0) break;
2014
2015 pthread_rwlock_rdlock(&lock);
2016 current = current->next;
2017 pthread_rwlock_unlock(&lock);
2018 }
2019 return ret;
2020}
2021
2022__attribute__((__visibility__("hidden")))
2023void __dl_vseterr(const char *, va_list);
2024
2025static void error(const char *fmt, ...)
2026{
2027 va_list ap;
2028 va_start(ap, fmt);
2029 if (!runtime) {
2030 vdprintf(2, fmt, ap);
2031 dprintf(2, "\n");
2032 ldso_fail = 1;
2033 va_end(ap);
2034 return;
2035 }
2036 __dl_vseterr(fmt, ap);
2037 va_end(ap);
2038}
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