1 #define _GNU_SOURCE
2 #define SYSCALL_NO_TLS 1
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 <semaphore.h>
21 #include <sys/membarrier.h>
22 #include "pthread_impl.h"
23 #include "fork_impl.h"
24 #include "libc.h"
25 #include "dynlink.h"
26
27 #define malloc __libc_malloc
28 #define calloc __libc_calloc
29 #define realloc __libc_realloc
30 #define free __libc_free
31
32 static void error(const char *, ...);
33
34 #define MAXP2(a,b) (-(-(a)&-(b)))
35 #define ALIGN(x,y) ((x)+(y)-1 & -(y))
36
37 #define container_of(p,t,m) ((t*)((char *)(p)-offsetof(t,m)))
38 #define countof(a) ((sizeof (a))/(sizeof (a)[0]))
39
40 struct debug {
41 int ver;
42 void *head;
43 void (*bp)(void);
44 int state;
45 void *base;
46 };
47
48 struct td_index {
49 size_t args[2];
50 struct td_index *next;
51 };
52
53 struct dso {
54 #if DL_FDPIC
55 struct fdpic_loadmap *loadmap;
56 #else
57 unsigned char *base;
58 #endif
59 char *name;
60 size_t *dynv;
61 struct dso *next, *prev;
62
63 Phdr *phdr;
64 int phnum;
65 size_t phentsize;
66 Sym *syms;
67 Elf_Symndx *hashtab;
68 uint32_t *ghashtab;
69 int16_t *versym;
70 char *strings;
71 struct dso *syms_next, *lazy_next;
72 size_t *lazy, lazy_cnt;
73 unsigned char *map;
74 size_t map_len;
75 char relocated;
76 char constructed;
77 char kernel_mapped;
78 char mark;
79 char bfs_built;
80 char runtime_loaded;
81 struct dso **deps, *needed_by;
82 size_t ndeps_direct;
83 size_t next_dep;
84 pthread_t ctor_visitor;
85 char *rpath_orig, *rpath;
86 struct tls_module tls;
87 size_t tls_id;
88 size_t relro_start, relro_end;
89 uintptr_t *new_dtv;
90 unsigned char *new_tls;
91 struct td_index *td_index;
92 struct dso *fini_next;
93 char *shortname;
94 #if DL_FDPIC
95 unsigned char *base;
96 #else
97 struct fdpic_loadmap *loadmap;
98 #endif
99 struct funcdesc {
100 void *addr;
101 size_t *got;
102 } *funcdescs;
103 size_t *got;
104 char buf[];
105 };
106
107 struct symdef {
108 Sym *sym;
109 struct dso *dso;
110 };
111
112 typedef void (*stage3_func)(size_t *, size_t *);
113
114 static struct builtin_tls {
115 char c;
116 struct pthread pt;
117 void *space[16];
118 } builtin_tls[1];
119 #define MIN_TLS_ALIGN offsetof(struct builtin_tls, pt)
120
121 #define ADDEND_LIMIT 4096
122 static size_t *saved_addends, *apply_addends_to;
123
124 static struct dso ldso;
125 static struct dso *head, *tail, *fini_head, *syms_tail, *lazy_head;
126 static char *env_path, *sys_path;
127 static unsigned long long gencnt;
128 static int runtime;
129 static int ldd_mode;
130 static int ldso_fail;
131 static int noload;
132 static int shutting_down;
133 static jmp_buf *rtld_fail;
134 static pthread_rwlock_t lock;
135 static struct debug debug;
136 static struct tls_module *tls_tail;
137 static size_t tls_cnt, tls_offset, tls_align = MIN_TLS_ALIGN;
138 static size_t static_tls_cnt;
139 static pthread_mutex_t init_fini_lock;
140 static pthread_cond_t ctor_cond;
141 static struct dso *builtin_deps[2];
142 static struct dso *const no_deps[1];
143 static struct dso *builtin_ctor_queue[4];
144 static struct dso **main_ctor_queue;
145 static struct fdpic_loadmap *app_loadmap;
146 static struct fdpic_dummy_loadmap app_dummy_loadmap;
147
148 struct debug *_dl_debug_addr = &debug;
149
150 extern hidden int __malloc_replaced;
151
152 hidden void (*const __init_array_start)(void)=0, (*const __fini_array_start)(void)=0;
153
154 extern hidden void (*const __init_array_end)(void), (*const __fini_array_end)(void);
155
156 weak_alias(__init_array_start, __init_array_end);
157 weak_alias(__fini_array_start, __fini_array_end);
158
dl_strcmp(const char * l,const char * r)159 static int dl_strcmp(const char *l, const char *r)
160 {
161 for (; *l==*r && *l; l++, r++);
162 return *(unsigned char *)l - *(unsigned char *)r;
163 }
164 #define strcmp(l,r) dl_strcmp(l,r)
165
166 /* Compute load address for a virtual address in a given dso. */
167 #if DL_FDPIC
laddr(const struct dso * p,size_t v)168 static void *laddr(const struct dso *p, size_t v)
169 {
170 size_t j=0;
171 if (!p->loadmap) return p->base + v;
172 for (j=0; v-p->loadmap->segs[j].p_vaddr >= p->loadmap->segs[j].p_memsz; j++);
173 return (void *)(v - p->loadmap->segs[j].p_vaddr + p->loadmap->segs[j].addr);
174 }
laddr_pg(const struct dso * p,size_t v)175 static void *laddr_pg(const struct dso *p, size_t v)
176 {
177 size_t j=0;
178 size_t pgsz = PAGE_SIZE;
179 if (!p->loadmap) return p->base + v;
180 for (j=0; ; j++) {
181 size_t a = p->loadmap->segs[j].p_vaddr;
182 size_t b = a + p->loadmap->segs[j].p_memsz;
183 a &= -pgsz;
184 b += pgsz-1;
185 b &= -pgsz;
186 if (v-a<b-a) break;
187 }
188 return (void *)(v - p->loadmap->segs[j].p_vaddr + p->loadmap->segs[j].addr);
189 }
fdbarrier(void * p)190 static void (*fdbarrier(void *p))()
191 {
192 void (*fd)();
193 __asm__("" : "=r"(fd) : "0"(p));
194 return fd;
195 }
196 #define fpaddr(p, v) fdbarrier((&(struct funcdesc){ \
197 laddr(p, v), (p)->got }))
198 #else
199 #define laddr(p, v) (void *)((p)->base + (v))
200 #define laddr_pg(p, v) laddr(p, v)
201 #define fpaddr(p, v) ((void (*)())laddr(p, v))
202 #endif
203
decode_vec(size_t * v,size_t * a,size_t cnt)204 static void decode_vec(size_t *v, size_t *a, size_t cnt)
205 {
206 size_t i;
207 for (i=0; i<cnt; i++) a[i] = 0;
208 for (; v[0]; v+=2) if (v[0]-1<cnt-1) {
209 a[0] |= 1UL<<v[0];
210 a[v[0]] = v[1];
211 }
212 }
213
search_vec(size_t * v,size_t * r,size_t key)214 static int search_vec(size_t *v, size_t *r, size_t key)
215 {
216 for (; v[0]!=key; v+=2)
217 if (!v[0]) return 0;
218 *r = v[1];
219 return 1;
220 }
221
sysv_hash(const char * s0)222 static uint32_t sysv_hash(const char *s0)
223 {
224 const unsigned char *s = (void *)s0;
225 uint_fast32_t h = 0;
226 while (*s) {
227 h = 16*h + *s++;
228 h ^= h>>24 & 0xf0;
229 }
230 return h & 0xfffffff;
231 }
232
gnu_hash(const char * s0)233 static uint32_t gnu_hash(const char *s0)
234 {
235 const unsigned char *s = (void *)s0;
236 uint_fast32_t h = 5381;
237 for (; *s; s++)
238 h += h*32 + *s;
239 return h;
240 }
241
sysv_lookup(const char * s,uint32_t h,struct dso * dso)242 static Sym *sysv_lookup(const char *s, uint32_t h, struct dso *dso)
243 {
244 size_t i;
245 Sym *syms = dso->syms;
246 Elf_Symndx *hashtab = dso->hashtab;
247 char *strings = dso->strings;
248 for (i=hashtab[2+h%hashtab[0]]; i; i=hashtab[2+hashtab[0]+i]) {
249 if ((!dso->versym || dso->versym[i] >= 0)
250 && (!strcmp(s, strings+syms[i].st_name)))
251 return syms+i;
252 }
253 return 0;
254 }
255
gnu_lookup(uint32_t h1,uint32_t * hashtab,struct dso * dso,const char * s)256 static Sym *gnu_lookup(uint32_t h1, uint32_t *hashtab, struct dso *dso, const char *s)
257 {
258 uint32_t nbuckets = hashtab[0];
259 uint32_t *buckets = hashtab + 4 + hashtab[2]*(sizeof(size_t)/4);
260 uint32_t i = buckets[h1 % nbuckets];
261
262 if (!i) return 0;
263
264 uint32_t *hashval = buckets + nbuckets + (i - hashtab[1]);
265
266 for (h1 |= 1; ; i++) {
267 uint32_t h2 = *hashval++;
268 if ((h1 == (h2|1)) && (!dso->versym || dso->versym[i] >= 0)
269 && !strcmp(s, dso->strings + dso->syms[i].st_name))
270 return dso->syms+i;
271 if (h2 & 1) break;
272 }
273
274 return 0;
275 }
276
gnu_lookup_filtered(uint32_t h1,uint32_t * hashtab,struct dso * dso,const char * s,uint32_t fofs,size_t fmask)277 static Sym *gnu_lookup_filtered(uint32_t h1, uint32_t *hashtab, struct dso *dso, const char *s, uint32_t fofs, size_t fmask)
278 {
279 const size_t *bloomwords = (const void *)(hashtab+4);
280 size_t f = bloomwords[fofs & (hashtab[2]-1)];
281 if (!(f & fmask)) return 0;
282
283 f >>= (h1 >> hashtab[3]) % (8 * sizeof f);
284 if (!(f & 1)) return 0;
285
286 return gnu_lookup(h1, hashtab, dso, s);
287 }
288
289 #define OK_TYPES (1<<STT_NOTYPE | 1<<STT_OBJECT | 1<<STT_FUNC | 1<<STT_COMMON | 1<<STT_TLS)
290 #define OK_BINDS (1<<STB_GLOBAL | 1<<STB_WEAK | 1<<STB_GNU_UNIQUE)
291
292 #ifndef ARCH_SYM_REJECT_UND
293 #define ARCH_SYM_REJECT_UND(s) 0
294 #endif
295
296 #if defined(__GNUC__)
297 __attribute__((always_inline))
298 #endif
find_sym2(struct dso * dso,const char * s,int need_def,int use_deps)299 static inline struct symdef find_sym2(struct dso *dso, const char *s, int need_def, int use_deps)
300 {
301 uint32_t h = 0, gh = gnu_hash(s), gho = gh / (8*sizeof(size_t)), *ght;
302 size_t ghm = 1ul << gh % (8*sizeof(size_t));
303 struct symdef def = {0};
304 struct dso **deps = use_deps ? dso->deps : 0;
305 for (; dso; dso=use_deps ? *deps++ : dso->syms_next) {
306 Sym *sym;
307 if ((ght = dso->ghashtab)) {
308 sym = gnu_lookup_filtered(gh, ght, dso, s, gho, ghm);
309 } else {
310 if (!h) h = sysv_hash(s);
311 sym = sysv_lookup(s, h, dso);
312 }
313 if (!sym) continue;
314 if (!sym->st_shndx)
315 if (need_def || (sym->st_info&0xf) == STT_TLS
316 || ARCH_SYM_REJECT_UND(sym))
317 continue;
318 if (!sym->st_value)
319 if ((sym->st_info&0xf) != STT_TLS)
320 continue;
321 if (!(1<<(sym->st_info&0xf) & OK_TYPES)) continue;
322 if (!(1<<(sym->st_info>>4) & OK_BINDS)) continue;
323 def.sym = sym;
324 def.dso = dso;
325 break;
326 }
327 return def;
328 }
329
find_sym(struct dso * dso,const char * s,int need_def)330 static struct symdef find_sym(struct dso *dso, const char *s, int need_def)
331 {
332 return find_sym2(dso, s, need_def, 0);
333 }
334
do_relocs(struct dso * dso,size_t * rel,size_t rel_size,size_t stride)335 static void do_relocs(struct dso *dso, size_t *rel, size_t rel_size, size_t stride)
336 {
337 unsigned char *base = dso->base;
338 Sym *syms = dso->syms;
339 char *strings = dso->strings;
340 Sym *sym;
341 const char *name;
342 void *ctx;
343 int type;
344 int sym_index;
345 struct symdef def;
346 size_t *reloc_addr;
347 size_t sym_val;
348 size_t tls_val;
349 size_t addend;
350 int skip_relative = 0, reuse_addends = 0, save_slot = 0;
351
352 if (dso == &ldso) {
353 /* Only ldso's REL table needs addend saving/reuse. */
354 if (rel == apply_addends_to)
355 reuse_addends = 1;
356 skip_relative = 1;
357 }
358
359 for (; rel_size; rel+=stride, rel_size-=stride*sizeof(size_t)) {
360 if (skip_relative && IS_RELATIVE(rel[1], dso->syms)) continue;
361 type = R_TYPE(rel[1]);
362 if (type == REL_NONE) continue;
363 reloc_addr = laddr(dso, rel[0]);
364
365 if (stride > 2) {
366 addend = rel[2];
367 } else if (type==REL_GOT || type==REL_PLT|| type==REL_COPY) {
368 addend = 0;
369 } else if (reuse_addends) {
370 /* Save original addend in stage 2 where the dso
371 * chain consists of just ldso; otherwise read back
372 * saved addend since the inline one was clobbered. */
373 if (head==&ldso)
374 saved_addends[save_slot] = *reloc_addr;
375 addend = saved_addends[save_slot++];
376 } else {
377 addend = *reloc_addr;
378 }
379
380 sym_index = R_SYM(rel[1]);
381 if (sym_index) {
382 sym = syms + sym_index;
383 name = strings + sym->st_name;
384 ctx = type==REL_COPY ? head->syms_next : head;
385 def = (sym->st_info>>4) == STB_LOCAL
386 ? (struct symdef){ .dso = dso, .sym = sym }
387 : find_sym(ctx, name, type==REL_PLT);
388 if (!def.sym && (sym->st_shndx != SHN_UNDEF
389 || sym->st_info>>4 != STB_WEAK)) {
390 if (dso->lazy && (type==REL_PLT || type==REL_GOT)) {
391 dso->lazy[3*dso->lazy_cnt+0] = rel[0];
392 dso->lazy[3*dso->lazy_cnt+1] = rel[1];
393 dso->lazy[3*dso->lazy_cnt+2] = addend;
394 dso->lazy_cnt++;
395 continue;
396 }
397 error("Error relocating %s: %s: symbol not found",
398 dso->name, name);
399 if (runtime) longjmp(*rtld_fail, 1);
400 continue;
401 }
402 } else {
403 sym = 0;
404 def.sym = 0;
405 def.dso = dso;
406 }
407
408 sym_val = def.sym ? (size_t)laddr(def.dso, def.sym->st_value) : 0;
409 tls_val = def.sym ? def.sym->st_value : 0;
410
411 if ((type == REL_TPOFF || type == REL_TPOFF_NEG)
412 && def.dso->tls_id > static_tls_cnt) {
413 error("Error relocating %s: %s: initial-exec TLS "
414 "resolves to dynamic definition in %s",
415 dso->name, name, def.dso->name);
416 longjmp(*rtld_fail, 1);
417 }
418
419 switch(type) {
420 case REL_OFFSET:
421 addend -= (size_t)reloc_addr;
422 case REL_SYMBOLIC:
423 case REL_GOT:
424 case REL_PLT:
425 *reloc_addr = sym_val + addend;
426 break;
427 case REL_USYMBOLIC:
428 memcpy(reloc_addr, &(size_t){sym_val + addend}, sizeof(size_t));
429 break;
430 case REL_RELATIVE:
431 *reloc_addr = (size_t)base + addend;
432 break;
433 case REL_SYM_OR_REL:
434 if (sym) *reloc_addr = sym_val + addend;
435 else *reloc_addr = (size_t)base + addend;
436 break;
437 case REL_COPY:
438 memcpy(reloc_addr, (void *)sym_val, sym->st_size);
439 break;
440 case REL_OFFSET32:
441 *(uint32_t *)reloc_addr = sym_val + addend
442 - (size_t)reloc_addr;
443 break;
444 case REL_FUNCDESC:
445 *reloc_addr = def.sym ? (size_t)(def.dso->funcdescs
446 + (def.sym - def.dso->syms)) : 0;
447 break;
448 case REL_FUNCDESC_VAL:
449 if ((sym->st_info&0xf) == STT_SECTION) *reloc_addr += sym_val;
450 else *reloc_addr = sym_val;
451 reloc_addr[1] = def.sym ? (size_t)def.dso->got : 0;
452 break;
453 case REL_DTPMOD:
454 *reloc_addr = def.dso->tls_id;
455 break;
456 case REL_DTPOFF:
457 *reloc_addr = tls_val + addend - DTP_OFFSET;
458 break;
459 #ifdef TLS_ABOVE_TP
460 case REL_TPOFF:
461 *reloc_addr = tls_val + def.dso->tls.offset + TPOFF_K + addend;
462 break;
463 #else
464 case REL_TPOFF:
465 *reloc_addr = tls_val - def.dso->tls.offset + addend;
466 break;
467 case REL_TPOFF_NEG:
468 *reloc_addr = def.dso->tls.offset - tls_val + addend;
469 break;
470 #endif
471 case REL_TLSDESC:
472 if (stride<3) addend = reloc_addr[1];
473 if (def.dso->tls_id > static_tls_cnt) {
474 struct td_index *new = malloc(sizeof *new);
475 if (!new) {
476 error(
477 "Error relocating %s: cannot allocate TLSDESC for %s",
478 dso->name, sym ? name : "(local)" );
479 longjmp(*rtld_fail, 1);
480 }
481 new->next = dso->td_index;
482 dso->td_index = new;
483 new->args[0] = def.dso->tls_id;
484 new->args[1] = tls_val + addend - DTP_OFFSET;
485 reloc_addr[0] = (size_t)__tlsdesc_dynamic;
486 reloc_addr[1] = (size_t)new;
487 } else {
488 reloc_addr[0] = (size_t)__tlsdesc_static;
489 #ifdef TLS_ABOVE_TP
490 reloc_addr[1] = tls_val + def.dso->tls.offset
491 + TPOFF_K + addend;
492 #else
493 reloc_addr[1] = tls_val - def.dso->tls.offset
494 + addend;
495 #endif
496 }
497 #ifdef TLSDESC_BACKWARDS
498 /* Some archs (32-bit ARM at least) invert the order of
499 * the descriptor members. Fix them up here. */
500 size_t tmp = reloc_addr[0];
501 reloc_addr[0] = reloc_addr[1];
502 reloc_addr[1] = tmp;
503 #endif
504 break;
505 default:
506 error("Error relocating %s: unsupported relocation type %d",
507 dso->name, type);
508 if (runtime) longjmp(*rtld_fail, 1);
509 continue;
510 }
511 }
512 }
513
redo_lazy_relocs()514 static void redo_lazy_relocs()
515 {
516 struct dso *p = lazy_head, *next;
517 lazy_head = 0;
518 for (; p; p=next) {
519 next = p->lazy_next;
520 size_t size = p->lazy_cnt*3*sizeof(size_t);
521 p->lazy_cnt = 0;
522 do_relocs(p, p->lazy, size, 3);
523 if (p->lazy_cnt) {
524 p->lazy_next = lazy_head;
525 lazy_head = p;
526 } else {
527 free(p->lazy);
528 p->lazy = 0;
529 p->lazy_next = 0;
530 }
531 }
532 }
533
534 /* A huge hack: to make up for the wastefulness of shared libraries
535 * needing at least a page of dirty memory even if they have no global
536 * data, we reclaim the gaps at the beginning and end of writable maps
537 * and "donate" them to the heap. */
538
reclaim(struct dso * dso,size_t start,size_t end)539 static void reclaim(struct dso *dso, size_t start, size_t end)
540 {
541 if (start >= dso->relro_start && start < dso->relro_end) start = dso->relro_end;
542 if (end >= dso->relro_start && end < dso->relro_end) end = dso->relro_start;
543 if (start >= end) return;
544 char *base = laddr_pg(dso, start);
545 __malloc_donate(base, base+(end-start));
546 }
547
reclaim_gaps(struct dso * dso)548 static void reclaim_gaps(struct dso *dso)
549 {
550 Phdr *ph = dso->phdr;
551 size_t phcnt = dso->phnum;
552
553 for (; phcnt--; ph=(void *)((char *)ph+dso->phentsize)) {
554 if (ph->p_type!=PT_LOAD) continue;
555 if ((ph->p_flags&(PF_R|PF_W))!=(PF_R|PF_W)) continue;
556 reclaim(dso, ph->p_vaddr & -PAGE_SIZE, ph->p_vaddr);
557 reclaim(dso, ph->p_vaddr+ph->p_memsz,
558 ph->p_vaddr+ph->p_memsz+PAGE_SIZE-1 & -PAGE_SIZE);
559 }
560 }
561
read_loop(int fd,void * p,size_t n)562 static ssize_t read_loop(int fd, void *p, size_t n)
563 {
564 for (size_t i=0; i<n; ) {
565 ssize_t l = read(fd, (char *)p+i, n-i);
566 if (l<0) {
567 if (errno==EINTR) continue;
568 else return -1;
569 }
570 if (l==0) return i;
571 i += l;
572 }
573 return n;
574 }
575
mmap_fixed(void * p,size_t n,int prot,int flags,int fd,off_t off)576 static void *mmap_fixed(void *p, size_t n, int prot, int flags, int fd, off_t off)
577 {
578 static int no_map_fixed;
579 char *q;
580 if (!n) return p;
581 if (!no_map_fixed) {
582 q = mmap(p, n, prot, flags|MAP_FIXED, fd, off);
583 if (!DL_NOMMU_SUPPORT || q != MAP_FAILED || errno != EINVAL)
584 return q;
585 no_map_fixed = 1;
586 }
587 /* Fallbacks for MAP_FIXED failure on NOMMU kernels. */
588 if (flags & MAP_ANONYMOUS) {
589 memset(p, 0, n);
590 return p;
591 }
592 ssize_t r;
593 if (lseek(fd, off, SEEK_SET) < 0) return MAP_FAILED;
594 for (q=p; n; q+=r, off+=r, n-=r) {
595 r = read(fd, q, n);
596 if (r < 0 && errno != EINTR) return MAP_FAILED;
597 if (!r) {
598 memset(q, 0, n);
599 break;
600 }
601 }
602 return p;
603 }
604
unmap_library(struct dso * dso)605 static void unmap_library(struct dso *dso)
606 {
607 if (dso->loadmap) {
608 size_t i;
609 for (i=0; i<dso->loadmap->nsegs; i++) {
610 if (!dso->loadmap->segs[i].p_memsz)
611 continue;
612 munmap((void *)dso->loadmap->segs[i].addr,
613 dso->loadmap->segs[i].p_memsz);
614 }
615 free(dso->loadmap);
616 } else if (dso->map && dso->map_len) {
617 munmap(dso->map, dso->map_len);
618 }
619 }
620
map_library(int fd,struct dso * dso)621 static void *map_library(int fd, struct dso *dso)
622 {
623 Ehdr buf[(896+sizeof(Ehdr))/sizeof(Ehdr)];
624 void *allocated_buf=0;
625 size_t phsize;
626 size_t addr_min=SIZE_MAX, addr_max=0, map_len;
627 size_t this_min, this_max;
628 size_t nsegs = 0;
629 off_t off_start;
630 Ehdr *eh;
631 Phdr *ph, *ph0;
632 unsigned prot;
633 unsigned char *map=MAP_FAILED, *base;
634 size_t dyn=0;
635 size_t tls_image=0;
636 size_t i;
637
638 ssize_t l = read(fd, buf, sizeof buf);
639 eh = buf;
640 if (l<0) return 0;
641 if (l<sizeof *eh || (eh->e_type != ET_DYN && eh->e_type != ET_EXEC))
642 goto noexec;
643 phsize = eh->e_phentsize * eh->e_phnum;
644 if (phsize > sizeof buf - sizeof *eh) {
645 allocated_buf = malloc(phsize);
646 if (!allocated_buf) return 0;
647 l = pread(fd, allocated_buf, phsize, eh->e_phoff);
648 if (l < 0) goto error;
649 if (l != phsize) goto noexec;
650 ph = ph0 = allocated_buf;
651 } else if (eh->e_phoff + phsize > l) {
652 l = pread(fd, buf+1, phsize, eh->e_phoff);
653 if (l < 0) goto error;
654 if (l != phsize) goto noexec;
655 ph = ph0 = (void *)(buf + 1);
656 } else {
657 ph = ph0 = (void *)((char *)buf + eh->e_phoff);
658 }
659 for (i=eh->e_phnum; i; i--, ph=(void *)((char *)ph+eh->e_phentsize)) {
660 if (ph->p_type == PT_DYNAMIC) {
661 dyn = ph->p_vaddr;
662 } else if (ph->p_type == PT_TLS) {
663 tls_image = ph->p_vaddr;
664 dso->tls.align = ph->p_align;
665 dso->tls.len = ph->p_filesz;
666 dso->tls.size = ph->p_memsz;
667 } else if (ph->p_type == PT_GNU_RELRO) {
668 dso->relro_start = ph->p_vaddr & -PAGE_SIZE;
669 dso->relro_end = (ph->p_vaddr + ph->p_memsz) & -PAGE_SIZE;
670 } else if (ph->p_type == PT_GNU_STACK) {
671 if (!runtime && ph->p_memsz > __default_stacksize) {
672 __default_stacksize =
673 ph->p_memsz < DEFAULT_STACK_MAX ?
674 ph->p_memsz : DEFAULT_STACK_MAX;
675 }
676 }
677 if (ph->p_type != PT_LOAD) continue;
678 nsegs++;
679 if (ph->p_vaddr < addr_min) {
680 addr_min = ph->p_vaddr;
681 off_start = ph->p_offset;
682 prot = (((ph->p_flags&PF_R) ? PROT_READ : 0) |
683 ((ph->p_flags&PF_W) ? PROT_WRITE: 0) |
684 ((ph->p_flags&PF_X) ? PROT_EXEC : 0));
685 }
686 if (ph->p_vaddr+ph->p_memsz > addr_max) {
687 addr_max = ph->p_vaddr+ph->p_memsz;
688 }
689 }
690 if (!dyn) goto noexec;
691 if (DL_FDPIC && !(eh->e_flags & FDPIC_CONSTDISP_FLAG)) {
692 dso->loadmap = calloc(1, sizeof *dso->loadmap
693 + nsegs * sizeof *dso->loadmap->segs);
694 if (!dso->loadmap) goto error;
695 dso->loadmap->nsegs = nsegs;
696 for (ph=ph0, i=0; i<nsegs; ph=(void *)((char *)ph+eh->e_phentsize)) {
697 if (ph->p_type != PT_LOAD) continue;
698 prot = (((ph->p_flags&PF_R) ? PROT_READ : 0) |
699 ((ph->p_flags&PF_W) ? PROT_WRITE: 0) |
700 ((ph->p_flags&PF_X) ? PROT_EXEC : 0));
701 map = mmap(0, ph->p_memsz + (ph->p_vaddr & PAGE_SIZE-1),
702 prot, MAP_PRIVATE,
703 fd, ph->p_offset & -PAGE_SIZE);
704 if (map == MAP_FAILED) {
705 unmap_library(dso);
706 goto error;
707 }
708 dso->loadmap->segs[i].addr = (size_t)map +
709 (ph->p_vaddr & PAGE_SIZE-1);
710 dso->loadmap->segs[i].p_vaddr = ph->p_vaddr;
711 dso->loadmap->segs[i].p_memsz = ph->p_memsz;
712 i++;
713 if (prot & PROT_WRITE) {
714 size_t brk = (ph->p_vaddr & PAGE_SIZE-1)
715 + ph->p_filesz;
716 size_t pgbrk = brk + PAGE_SIZE-1 & -PAGE_SIZE;
717 size_t pgend = brk + ph->p_memsz - ph->p_filesz
718 + PAGE_SIZE-1 & -PAGE_SIZE;
719 if (pgend > pgbrk && mmap_fixed(map+pgbrk,
720 pgend-pgbrk, prot,
721 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS,
722 -1, off_start) == MAP_FAILED)
723 goto error;
724 memset(map + brk, 0, pgbrk-brk);
725 }
726 }
727 map = (void *)dso->loadmap->segs[0].addr;
728 map_len = 0;
729 goto done_mapping;
730 }
731 addr_max += PAGE_SIZE-1;
732 addr_max &= -PAGE_SIZE;
733 addr_min &= -PAGE_SIZE;
734 off_start &= -PAGE_SIZE;
735 map_len = addr_max - addr_min + off_start;
736 /* The first time, we map too much, possibly even more than
737 * the length of the file. This is okay because we will not
738 * use the invalid part; we just need to reserve the right
739 * amount of virtual address space to map over later. */
740 map = DL_NOMMU_SUPPORT
741 ? mmap((void *)addr_min, map_len, PROT_READ|PROT_WRITE|PROT_EXEC,
742 MAP_PRIVATE|MAP_ANONYMOUS, -1, 0)
743 : mmap((void *)addr_min, map_len, prot,
744 MAP_PRIVATE, fd, off_start);
745 if (map==MAP_FAILED) goto error;
746 dso->map = map;
747 dso->map_len = map_len;
748 /* If the loaded file is not relocatable and the requested address is
749 * not available, then the load operation must fail. */
750 if (eh->e_type != ET_DYN && addr_min && map!=(void *)addr_min) {
751 errno = EBUSY;
752 goto error;
753 }
754 base = map - addr_min;
755 dso->phdr = 0;
756 dso->phnum = 0;
757 for (ph=ph0, i=eh->e_phnum; i; i--, ph=(void *)((char *)ph+eh->e_phentsize)) {
758 if (ph->p_type != PT_LOAD) continue;
759 /* Check if the programs headers are in this load segment, and
760 * if so, record the address for use by dl_iterate_phdr. */
761 if (!dso->phdr && eh->e_phoff >= ph->p_offset
762 && eh->e_phoff+phsize <= ph->p_offset+ph->p_filesz) {
763 dso->phdr = (void *)(base + ph->p_vaddr
764 + (eh->e_phoff-ph->p_offset));
765 dso->phnum = eh->e_phnum;
766 dso->phentsize = eh->e_phentsize;
767 }
768 this_min = ph->p_vaddr & -PAGE_SIZE;
769 this_max = ph->p_vaddr+ph->p_memsz+PAGE_SIZE-1 & -PAGE_SIZE;
770 off_start = ph->p_offset & -PAGE_SIZE;
771 prot = (((ph->p_flags&PF_R) ? PROT_READ : 0) |
772 ((ph->p_flags&PF_W) ? PROT_WRITE: 0) |
773 ((ph->p_flags&PF_X) ? PROT_EXEC : 0));
774 if ((ph->p_flags & PF_R) && (ph->p_flags & PF_X) && (!(ph->p_flags & PF_W))) {
775 Phdr *next_ph = ph;
776 for (int j = i - 1; j > 0; j--) {
777 next_ph = (void *)((char *)next_ph+eh->e_phentsize);
778 if (next_ph->p_type != PT_LOAD) {
779 continue;
780 }
781 size_t p_vaddr = (next_ph->p_vaddr & -(PAGE_SIZE));
782 if (p_vaddr > this_max) {
783 mprotect(base + this_max, p_vaddr - this_max , PROT_READ);
784 }
785 break;
786 }
787 }
788 /* Reuse the existing mapping for the lowest-address LOAD */
789 if ((ph->p_vaddr & -PAGE_SIZE) != addr_min || DL_NOMMU_SUPPORT)
790 if (mmap_fixed(base+this_min, this_max-this_min, prot, MAP_PRIVATE|MAP_FIXED, fd, off_start) == MAP_FAILED)
791 goto error;
792 if (ph->p_memsz > ph->p_filesz && (ph->p_flags&PF_W)) {
793 size_t brk = (size_t)base+ph->p_vaddr+ph->p_filesz;
794 size_t pgbrk = brk+PAGE_SIZE-1 & -PAGE_SIZE;
795 memset((void *)brk, 0, pgbrk-brk & PAGE_SIZE-1);
796 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)
797 goto error;
798 }
799 }
800 for (i=0; ((size_t *)(base+dyn))[i]; i+=2)
801 if (((size_t *)(base+dyn))[i]==DT_TEXTREL) {
802 if (mprotect(map, map_len, PROT_READ|PROT_WRITE|PROT_EXEC)
803 && errno != ENOSYS)
804 goto error;
805 break;
806 }
807 done_mapping:
808 dso->base = base;
809 dso->dynv = laddr(dso, dyn);
810 if (dso->tls.size) dso->tls.image = laddr(dso, tls_image);
811 free(allocated_buf);
812 return map;
813 noexec:
814 errno = ENOEXEC;
815 error:
816 if (map!=MAP_FAILED) unmap_library(dso);
817 free(allocated_buf);
818 return 0;
819 }
820
path_open(const char * name,const char * s,char * buf,size_t buf_size)821 static int path_open(const char *name, const char *s, char *buf, size_t buf_size)
822 {
823 size_t l;
824 int fd;
825 for (;;) {
826 s += strspn(s, ":\n");
827 l = strcspn(s, ":\n");
828 if (l-1 >= INT_MAX) return -1;
829 if (snprintf(buf, buf_size, "%.*s/%s", (int)l, s, name) < buf_size) {
830 if ((fd = open(buf, O_RDONLY|O_CLOEXEC))>=0) return fd;
831 switch (errno) {
832 case ENOENT:
833 case ENOTDIR:
834 case EACCES:
835 case ENAMETOOLONG:
836 break;
837 default:
838 /* Any negative value but -1 will inhibit
839 * futher path search. */
840 return -2;
841 }
842 }
843 s += l;
844 }
845 }
846
fixup_rpath(struct dso * p,char * buf,size_t buf_size)847 static int fixup_rpath(struct dso *p, char *buf, size_t buf_size)
848 {
849 size_t n, l;
850 const char *s, *t, *origin;
851 char *d;
852 if (p->rpath || !p->rpath_orig) return 0;
853 if (!strchr(p->rpath_orig, '$')) {
854 p->rpath = p->rpath_orig;
855 return 0;
856 }
857 n = 0;
858 s = p->rpath_orig;
859 while ((t=strchr(s, '$'))) {
860 if (strncmp(t, "$ORIGIN", 7) && strncmp(t, "${ORIGIN}", 9))
861 return 0;
862 s = t+1;
863 n++;
864 }
865 if (n > SSIZE_MAX/PATH_MAX) return 0;
866
867 if (p->kernel_mapped) {
868 /* $ORIGIN searches cannot be performed for the main program
869 * when it is suid/sgid/AT_SECURE. This is because the
870 * pathname is under the control of the caller of execve.
871 * For libraries, however, $ORIGIN can be processed safely
872 * since the library's pathname came from a trusted source
873 * (either system paths or a call to dlopen). */
874 if (libc.secure)
875 return 0;
876 l = readlink("/proc/self/exe", buf, buf_size);
877 if (l == -1) switch (errno) {
878 case ENOENT:
879 case ENOTDIR:
880 case EACCES:
881 break;
882 default:
883 return -1;
884 }
885 if (l >= buf_size)
886 return 0;
887 buf[l] = 0;
888 origin = buf;
889 } else {
890 origin = p->name;
891 }
892 t = strrchr(origin, '/');
893 if (t) {
894 l = t-origin;
895 } else {
896 /* Normally p->name will always be an absolute or relative
897 * pathname containing at least one '/' character, but in the
898 * case where ldso was invoked as a command to execute a
899 * program in the working directory, app.name may not. Fix. */
900 origin = ".";
901 l = 1;
902 }
903 /* Disallow non-absolute origins for suid/sgid/AT_SECURE. */
904 if (libc.secure && *origin != '/')
905 return 0;
906 p->rpath = malloc(strlen(p->rpath_orig) + n*l + 1);
907 if (!p->rpath) return -1;
908
909 d = p->rpath;
910 s = p->rpath_orig;
911 while ((t=strchr(s, '$'))) {
912 memcpy(d, s, t-s);
913 d += t-s;
914 memcpy(d, origin, l);
915 d += l;
916 /* It was determined previously that the '$' is followed
917 * either by "ORIGIN" or "{ORIGIN}". */
918 s = t + 7 + 2*(t[1]=='{');
919 }
920 strcpy(d, s);
921 return 0;
922 }
923
decode_dyn(struct dso * p)924 static void decode_dyn(struct dso *p)
925 {
926 size_t dyn[DYN_CNT];
927 decode_vec(p->dynv, dyn, DYN_CNT);
928 p->syms = laddr(p, dyn[DT_SYMTAB]);
929 p->strings = laddr(p, dyn[DT_STRTAB]);
930 if (dyn[0]&(1<<DT_HASH))
931 p->hashtab = laddr(p, dyn[DT_HASH]);
932 if (dyn[0]&(1<<DT_RPATH))
933 p->rpath_orig = p->strings + dyn[DT_RPATH];
934 if (dyn[0]&(1<<DT_RUNPATH))
935 p->rpath_orig = p->strings + dyn[DT_RUNPATH];
936 if (dyn[0]&(1<<DT_PLTGOT))
937 p->got = laddr(p, dyn[DT_PLTGOT]);
938 if (search_vec(p->dynv, dyn, DT_GNU_HASH))
939 p->ghashtab = laddr(p, *dyn);
940 if (search_vec(p->dynv, dyn, DT_VERSYM))
941 p->versym = laddr(p, *dyn);
942 }
943
count_syms(struct dso * p)944 static size_t count_syms(struct dso *p)
945 {
946 if (p->hashtab) return p->hashtab[1];
947
948 size_t nsym, i;
949 uint32_t *buckets = p->ghashtab + 4 + (p->ghashtab[2]*sizeof(size_t)/4);
950 uint32_t *hashval;
951 for (i = nsym = 0; i < p->ghashtab[0]; i++) {
952 if (buckets[i] > nsym)
953 nsym = buckets[i];
954 }
955 if (nsym) {
956 hashval = buckets + p->ghashtab[0] + (nsym - p->ghashtab[1]);
957 do nsym++;
958 while (!(*hashval++ & 1));
959 }
960 return nsym;
961 }
962
dl_mmap(size_t n)963 static void *dl_mmap(size_t n)
964 {
965 void *p;
966 int prot = PROT_READ|PROT_WRITE, flags = MAP_ANONYMOUS|MAP_PRIVATE;
967 #ifdef SYS_mmap2
968 p = (void *)__syscall(SYS_mmap2, 0, n, prot, flags, -1, 0);
969 #else
970 p = (void *)__syscall(SYS_mmap, 0, n, prot, flags, -1, 0);
971 #endif
972 return (unsigned long)p > -4096UL ? 0 : p;
973 }
974
makefuncdescs(struct dso * p)975 static void makefuncdescs(struct dso *p)
976 {
977 static int self_done;
978 size_t nsym = count_syms(p);
979 size_t i, size = nsym * sizeof(*p->funcdescs);
980
981 if (!self_done) {
982 p->funcdescs = dl_mmap(size);
983 self_done = 1;
984 } else {
985 p->funcdescs = malloc(size);
986 }
987 if (!p->funcdescs) {
988 if (!runtime) a_crash();
989 error("Error allocating function descriptors for %s", p->name);
990 longjmp(*rtld_fail, 1);
991 }
992 for (i=0; i<nsym; i++) {
993 if ((p->syms[i].st_info&0xf)==STT_FUNC && p->syms[i].st_shndx) {
994 p->funcdescs[i].addr = laddr(p, p->syms[i].st_value);
995 p->funcdescs[i].got = p->got;
996 } else {
997 p->funcdescs[i].addr = 0;
998 p->funcdescs[i].got = 0;
999 }
1000 }
1001 }
1002
load_library(const char * name,struct dso * needed_by)1003 static struct dso *load_library(const char *name, struct dso *needed_by)
1004 {
1005 char buf[2*NAME_MAX+2];
1006 char fullpath[2*NAME_MAX+2];
1007 const char *pathname;
1008 unsigned char *map;
1009 struct dso *p, temp_dso = {0};
1010 int fd;
1011 struct stat st;
1012 size_t alloc_size;
1013 int n_th = 0;
1014 int is_self = 0;
1015
1016 if (!*name) {
1017 errno = EINVAL;
1018 return 0;
1019 }
1020
1021 /* Catch and block attempts to reload the implementation itself */
1022 if (name[0]=='l' && name[1]=='i' && name[2]=='b') {
1023 static const char reserved[] =
1024 "c.pthread.rt.m.dl.util.xnet.";
1025 const char *rp, *next;
1026 for (rp=reserved; *rp; rp=next) {
1027 next = strchr(rp, '.') + 1;
1028 if (strncmp(name+3, rp, next-rp) == 0)
1029 break;
1030 }
1031 if (*rp) {
1032 if (ldd_mode) {
1033 /* Track which names have been resolved
1034 * and only report each one once. */
1035 static unsigned reported;
1036 unsigned mask = 1U<<(rp-reserved);
1037 if (!(reported & mask)) {
1038 reported |= mask;
1039 dprintf(1, "\t%s => %s (%p)\n",
1040 name, ldso.name,
1041 ldso.base);
1042 }
1043 }
1044 is_self = 1;
1045 }
1046 }
1047 if (!strcmp(name, ldso.name)) is_self = 1;
1048 if (is_self) {
1049 if (!ldso.prev) {
1050 tail->next = &ldso;
1051 ldso.prev = tail;
1052 tail = &ldso;
1053 }
1054 return &ldso;
1055 }
1056 if (strchr(name, '/')) {
1057 pathname = name;
1058 fd = open(name, O_RDONLY|O_CLOEXEC);
1059 } else {
1060 /* Search for the name to see if it's already loaded */
1061 for (p=head->next; p; p=p->next) {
1062 if (p->shortname && !strcmp(p->shortname, name)) {
1063 return p;
1064 }
1065 }
1066 if (strlen(name) > NAME_MAX) return 0;
1067 fd = -1;
1068 if (env_path) fd = path_open(name, env_path, buf, sizeof buf);
1069 for (p=needed_by; fd == -1 && p; p=p->needed_by) {
1070 if (fixup_rpath(p, buf, sizeof buf) < 0)
1071 fd = -2; /* Inhibit further search. */
1072 if (p->rpath)
1073 fd = path_open(name, p->rpath, buf, sizeof buf);
1074 }
1075 if (fd == -1) {
1076 if (!sys_path) {
1077 char *prefix = 0;
1078 size_t prefix_len;
1079 if (ldso.name[0]=='/') {
1080 char *s, *t, *z;
1081 for (s=t=z=ldso.name; *s; s++)
1082 if (*s=='/') z=t, t=s;
1083 prefix_len = z-ldso.name;
1084 if (prefix_len < PATH_MAX)
1085 prefix = ldso.name;
1086 }
1087 if (!prefix) {
1088 prefix = "";
1089 prefix_len = 0;
1090 }
1091 char etc_ldso_path[prefix_len + 1
1092 + sizeof "/etc/ld-musl-" LDSO_ARCH ".path"];
1093 snprintf(etc_ldso_path, sizeof etc_ldso_path,
1094 "%.*s/etc/ld-musl-" LDSO_ARCH ".path",
1095 (int)prefix_len, prefix);
1096 fd = open(etc_ldso_path, O_RDONLY|O_CLOEXEC);
1097 if (fd>=0) {
1098 size_t n = 0;
1099 if (!fstat(fd, &st)) n = st.st_size;
1100 if ((sys_path = malloc(n+1)))
1101 sys_path[n] = 0;
1102 if (!sys_path || read_loop(fd, sys_path, n)<0) {
1103
1104 free(sys_path);
1105 sys_path = "";
1106 }
1107 close(fd);
1108 } else if (errno != ENOENT) {
1109 sys_path = "";
1110 }
1111 }
1112 if (!sys_path || sys_path[0] == 0) sys_path = "/usr/lib:/lib:/usr/local/lib";
1113 fd = path_open(name, sys_path, buf, sizeof buf);
1114 }
1115 pathname = buf;
1116 }
1117 if (fd < 0) return 0;
1118
1119 if (pathname[0] != '/') {
1120 if (!realpath(pathname, fullpath)) {
1121 close(fd);
1122 return 0;
1123 }
1124 pathname = fullpath;
1125 }
1126
1127 for (p=head->next; p; p=p->next) {
1128 if (!strcmp(p->name, pathname)) {
1129 /* If this library was previously loaded with a
1130 * pathname but a search found the same inode,
1131 * setup its shortname so it can be found by name. */
1132 if (!p->shortname && pathname != name)
1133 p->shortname = strrchr(p->name, '/')+1;
1134 close(fd);
1135 return p;
1136 }
1137 }
1138 map = noload ? 0 : map_library(fd, &temp_dso);
1139 close(fd);
1140 if (!map) return 0;
1141
1142 /* Avoid the danger of getting two versions of libc mapped into the
1143 * same process when an absolute pathname was used. The symbols
1144 * checked are chosen to catch both musl and glibc, and to avoid
1145 * false positives from interposition-hack libraries. */
1146 decode_dyn(&temp_dso);
1147 if (find_sym(&temp_dso, "__libc_start_main", 1).sym &&
1148 find_sym(&temp_dso, "stdin", 1).sym) {
1149 unmap_library(&temp_dso);
1150 return load_library("libc.so", needed_by);
1151 }
1152 /* Past this point, if we haven't reached runtime yet, ldso has
1153 * committed either to use the mapped library or to abort execution.
1154 * Unmapping is not possible, so we can safely reclaim gaps. */
1155 if (!runtime) reclaim_gaps(&temp_dso);
1156
1157 /* Allocate storage for the new DSO. When there is TLS, this
1158 * storage must include a reservation for all pre-existing
1159 * threads to obtain copies of both the new TLS, and an
1160 * extended DTV capable of storing an additional slot for
1161 * the newly-loaded DSO. */
1162 alloc_size = sizeof *p + strlen(pathname) + 1;
1163 if (runtime && temp_dso.tls.image) {
1164 size_t per_th = temp_dso.tls.size + temp_dso.tls.align
1165 + sizeof(void *) * (tls_cnt+3);
1166 n_th = libc.threads_minus_1 + 1;
1167 if (n_th > SSIZE_MAX / per_th) alloc_size = SIZE_MAX;
1168 else alloc_size += n_th * per_th;
1169 }
1170 p = calloc(1, alloc_size);
1171 if (!p) {
1172 unmap_library(&temp_dso);
1173 return 0;
1174 }
1175 memcpy(p, &temp_dso, sizeof temp_dso);
1176 p->needed_by = needed_by;
1177 p->name = p->buf;
1178 p->runtime_loaded = runtime;
1179 strcpy(p->name, pathname);
1180 /* Add a shortname only if name arg was not an explicit pathname. */
1181 if (pathname != name) p->shortname = strrchr(p->name, '/')+1;
1182 if (p->tls.image) {
1183 p->tls_id = ++tls_cnt;
1184 tls_align = MAXP2(tls_align, p->tls.align);
1185 #ifdef TLS_ABOVE_TP
1186 p->tls.offset = tls_offset + ( (p->tls.align-1) &
1187 (-tls_offset + (uintptr_t)p->tls.image) );
1188 tls_offset = p->tls.offset + p->tls.size;
1189 #else
1190 tls_offset += p->tls.size + p->tls.align - 1;
1191 tls_offset -= (tls_offset + (uintptr_t)p->tls.image)
1192 & (p->tls.align-1);
1193 p->tls.offset = tls_offset;
1194 #endif
1195 p->new_dtv = (void *)(-sizeof(size_t) &
1196 (uintptr_t)(p->name+strlen(p->name)+sizeof(size_t)));
1197 p->new_tls = (void *)(p->new_dtv + n_th*(tls_cnt+1));
1198 if (tls_tail) tls_tail->next = &p->tls;
1199 else libc.tls_head = &p->tls;
1200 tls_tail = &p->tls;
1201 }
1202
1203 tail->next = p;
1204 p->prev = tail;
1205 tail = p;
1206
1207 if (DL_FDPIC) makefuncdescs(p);
1208
1209 if (ldd_mode) dprintf(1, "\t%s => %s (%p)\n", name, pathname, p->base);
1210
1211 return p;
1212 }
1213
load_direct_deps(struct dso * p)1214 static void load_direct_deps(struct dso *p)
1215 {
1216 size_t i, cnt=0;
1217
1218 if (p->deps) return;
1219 /* For head, all preloads are direct pseudo-dependencies.
1220 * Count and include them now to avoid realloc later. */
1221 if (p==head) for (struct dso *q=p->next; q; q=q->next)
1222 cnt++;
1223 for (i=0; p->dynv[i]; i+=2)
1224 if (p->dynv[i] == DT_NEEDED) cnt++;
1225 /* Use builtin buffer for apps with no external deps, to
1226 * preserve property of no runtime failure paths. */
1227 p->deps = (p==head && cnt<2) ? builtin_deps :
1228 calloc(cnt+1, sizeof *p->deps);
1229 if (!p->deps) {
1230 error("Error loading dependencies for %s", p->name);
1231 if (runtime) longjmp(*rtld_fail, 1);
1232 }
1233 cnt=0;
1234 if (p==head) for (struct dso *q=p->next; q; q=q->next)
1235 p->deps[cnt++] = q;
1236 for (i=0; p->dynv[i]; i+=2) {
1237 if (p->dynv[i] != DT_NEEDED) continue;
1238 struct dso *dep = load_library(p->strings + p->dynv[i+1], p);
1239 if (!dep) {
1240 error("Error loading shared library %s: %m (needed by %s)",
1241 p->strings + p->dynv[i+1], p->name);
1242 if (runtime) longjmp(*rtld_fail, 1);
1243 continue;
1244 }
1245 p->deps[cnt++] = dep;
1246 }
1247 p->deps[cnt] = 0;
1248 p->ndeps_direct = cnt;
1249 }
1250
load_deps(struct dso * p)1251 static void load_deps(struct dso *p)
1252 {
1253 if (p->deps) return;
1254 for (; p; p=p->next)
1255 load_direct_deps(p);
1256 }
1257
extend_bfs_deps(struct dso * p)1258 static void extend_bfs_deps(struct dso *p)
1259 {
1260 size_t i, j, cnt, ndeps_all;
1261 struct dso **tmp;
1262
1263 /* Can't use realloc if the original p->deps was allocated at
1264 * program entry and malloc has been replaced, or if it's
1265 * the builtin non-allocated trivial main program deps array. */
1266 int no_realloc = (__malloc_replaced && !p->runtime_loaded)
1267 || p->deps == builtin_deps;
1268
1269 if (p->bfs_built) return;
1270 ndeps_all = p->ndeps_direct;
1271
1272 /* Mark existing (direct) deps so they won't be duplicated. */
1273 for (i=0; p->deps[i]; i++)
1274 p->deps[i]->mark = 1;
1275
1276 /* For each dependency already in the list, copy its list of direct
1277 * dependencies to the list, excluding any items already in the
1278 * list. Note that the list this loop iterates over will grow during
1279 * the loop, but since duplicates are excluded, growth is bounded. */
1280 for (i=0; p->deps[i]; i++) {
1281 struct dso *dep = p->deps[i];
1282 for (j=cnt=0; j<dep->ndeps_direct; j++)
1283 if (!dep->deps[j]->mark) cnt++;
1284 tmp = no_realloc ?
1285 malloc(sizeof(*tmp) * (ndeps_all+cnt+1)) :
1286 realloc(p->deps, sizeof(*tmp) * (ndeps_all+cnt+1));
1287 if (!tmp) {
1288 error("Error recording dependencies for %s", p->name);
1289 if (runtime) longjmp(*rtld_fail, 1);
1290 continue;
1291 }
1292 if (no_realloc) {
1293 memcpy(tmp, p->deps, sizeof(*tmp) * (ndeps_all+1));
1294 no_realloc = 0;
1295 }
1296 p->deps = tmp;
1297 for (j=0; j<dep->ndeps_direct; j++) {
1298 if (dep->deps[j]->mark) continue;
1299 dep->deps[j]->mark = 1;
1300 p->deps[ndeps_all++] = dep->deps[j];
1301 }
1302 p->deps[ndeps_all] = 0;
1303 }
1304 p->bfs_built = 1;
1305 for (p=head; p; p=p->next)
1306 p->mark = 0;
1307 }
1308
load_preload(char * s)1309 static void load_preload(char *s)
1310 {
1311 int tmp;
1312 char *z;
1313 for (z=s; *z; s=z) {
1314 for ( ; *s && (isspace(*s) || *s==':'); s++);
1315 for (z=s; *z && !isspace(*z) && *z!=':'; z++);
1316 tmp = *z;
1317 *z = 0;
1318 load_library(s, 0);
1319 *z = tmp;
1320 }
1321 }
1322
add_syms(struct dso * p)1323 static void add_syms(struct dso *p)
1324 {
1325 if (!p->syms_next && syms_tail != p) {
1326 syms_tail->syms_next = p;
1327 syms_tail = p;
1328 }
1329 }
1330
revert_syms(struct dso * old_tail)1331 static void revert_syms(struct dso *old_tail)
1332 {
1333 struct dso *p, *next;
1334 /* Chop off the tail of the list of dsos that participate in
1335 * the global symbol table, reverting them to RTLD_LOCAL. */
1336 for (p=old_tail; p; p=next) {
1337 next = p->syms_next;
1338 p->syms_next = 0;
1339 }
1340 syms_tail = old_tail;
1341 }
1342
do_mips_relocs(struct dso * p,size_t * got)1343 static void do_mips_relocs(struct dso *p, size_t *got)
1344 {
1345 size_t i, j, rel[2];
1346 unsigned char *base = p->base;
1347 i=0; search_vec(p->dynv, &i, DT_MIPS_LOCAL_GOTNO);
1348 if (p==&ldso) {
1349 got += i;
1350 } else {
1351 while (i--) *got++ += (size_t)base;
1352 }
1353 j=0; search_vec(p->dynv, &j, DT_MIPS_GOTSYM);
1354 i=0; search_vec(p->dynv, &i, DT_MIPS_SYMTABNO);
1355 Sym *sym = p->syms + j;
1356 rel[0] = (unsigned char *)got - base;
1357 for (i-=j; i; i--, sym++, rel[0]+=sizeof(size_t)) {
1358 rel[1] = R_INFO(sym-p->syms, R_MIPS_JUMP_SLOT);
1359 do_relocs(p, rel, sizeof rel, 2);
1360 }
1361 }
1362
reloc_all(struct dso * p)1363 static void reloc_all(struct dso *p)
1364 {
1365 size_t dyn[DYN_CNT];
1366 for (; p; p=p->next) {
1367 if (p->relocated) continue;
1368 decode_vec(p->dynv, dyn, DYN_CNT);
1369 if (NEED_MIPS_GOT_RELOCS)
1370 do_mips_relocs(p, laddr(p, dyn[DT_PLTGOT]));
1371 do_relocs(p, laddr(p, dyn[DT_JMPREL]), dyn[DT_PLTRELSZ],
1372 2+(dyn[DT_PLTREL]==DT_RELA));
1373 do_relocs(p, laddr(p, dyn[DT_REL]), dyn[DT_RELSZ], 2);
1374 do_relocs(p, laddr(p, dyn[DT_RELA]), dyn[DT_RELASZ], 3);
1375
1376 if (head != &ldso && p->relro_start != p->relro_end &&
1377 mprotect(laddr(p, p->relro_start), p->relro_end-p->relro_start, PROT_READ)
1378 && errno != ENOSYS) {
1379 error("Error relocating %s: RELRO protection failed: %m",
1380 p->name);
1381 if (runtime) longjmp(*rtld_fail, 1);
1382 }
1383
1384 p->relocated = 1;
1385 }
1386 }
1387
kernel_mapped_dso(struct dso * p)1388 static void kernel_mapped_dso(struct dso *p)
1389 {
1390 size_t min_addr = -1, max_addr = 0, cnt;
1391 Phdr *ph = p->phdr;
1392 for (cnt = p->phnum; cnt--; ph = (void *)((char *)ph + p->phentsize)) {
1393 if (ph->p_type == PT_DYNAMIC) {
1394 p->dynv = laddr(p, ph->p_vaddr);
1395 } else if (ph->p_type == PT_GNU_RELRO) {
1396 p->relro_start = ph->p_vaddr & -PAGE_SIZE;
1397 p->relro_end = (ph->p_vaddr + ph->p_memsz) & -PAGE_SIZE;
1398 } else if (ph->p_type == PT_GNU_STACK) {
1399 if (!runtime && ph->p_memsz > __default_stacksize) {
1400 __default_stacksize =
1401 ph->p_memsz < DEFAULT_STACK_MAX ?
1402 ph->p_memsz : DEFAULT_STACK_MAX;
1403 }
1404 }
1405 if (ph->p_type != PT_LOAD) continue;
1406 if (ph->p_vaddr < min_addr)
1407 min_addr = ph->p_vaddr;
1408 if (ph->p_vaddr+ph->p_memsz > max_addr)
1409 max_addr = ph->p_vaddr+ph->p_memsz;
1410 }
1411 min_addr &= -PAGE_SIZE;
1412 max_addr = (max_addr + PAGE_SIZE-1) & -PAGE_SIZE;
1413 p->map = p->base + min_addr;
1414 p->map_len = max_addr - min_addr;
1415 p->kernel_mapped = 1;
1416 }
1417
__libc_exit_fini()1418 void __libc_exit_fini()
1419 {
1420 struct dso *p;
1421 size_t dyn[DYN_CNT];
1422 pthread_t self = __pthread_self();
1423
1424 /* Take both locks before setting shutting_down, so that
1425 * either lock is sufficient to read its value. The lock
1426 * order matches that in dlopen to avoid deadlock. */
1427 pthread_rwlock_wrlock(&lock);
1428 pthread_mutex_lock(&init_fini_lock);
1429 shutting_down = 1;
1430 pthread_rwlock_unlock(&lock);
1431 for (p=fini_head; p; p=p->fini_next) {
1432 while (p->ctor_visitor && p->ctor_visitor!=self)
1433 pthread_cond_wait(&ctor_cond, &init_fini_lock);
1434 if (!p->constructed) continue;
1435 decode_vec(p->dynv, dyn, DYN_CNT);
1436 if (dyn[0] & (1<<DT_FINI_ARRAY)) {
1437 size_t n = dyn[DT_FINI_ARRAYSZ]/sizeof(size_t);
1438 size_t *fn = (size_t *)laddr(p, dyn[DT_FINI_ARRAY])+n;
1439 while (n--) ((void (*)(void))*--fn)();
1440 }
1441 #ifndef NO_LEGACY_INITFINI
1442 if ((dyn[0] & (1<<DT_FINI)) && dyn[DT_FINI])
1443 fpaddr(p, dyn[DT_FINI])();
1444 #endif
1445 }
1446 }
1447
__ldso_atfork(int who)1448 void __ldso_atfork(int who)
1449 {
1450 if (who<0) {
1451 pthread_rwlock_wrlock(&lock);
1452 pthread_mutex_lock(&init_fini_lock);
1453 } else {
1454 pthread_mutex_unlock(&init_fini_lock);
1455 pthread_rwlock_unlock(&lock);
1456 }
1457 }
1458
queue_ctors(struct dso * dso)1459 static struct dso **queue_ctors(struct dso *dso)
1460 {
1461 size_t cnt, qpos, spos, i;
1462 struct dso *p, **queue, **stack;
1463
1464 if (ldd_mode) return 0;
1465
1466 /* Bound on queue size is the total number of indirect deps.
1467 * If a bfs deps list was built, we can use it. Otherwise,
1468 * bound by the total number of DSOs, which is always safe and
1469 * is reasonable we use it (for main app at startup). */
1470 if (dso->bfs_built) {
1471 for (cnt=0; dso->deps[cnt]; cnt++)
1472 dso->deps[cnt]->mark = 0;
1473 cnt++; /* self, not included in deps */
1474 } else {
1475 for (cnt=0, p=head; p; cnt++, p=p->next)
1476 p->mark = 0;
1477 }
1478 cnt++; /* termination slot */
1479 if (dso==head && cnt <= countof(builtin_ctor_queue))
1480 queue = builtin_ctor_queue;
1481 else
1482 queue = calloc(cnt, sizeof *queue);
1483
1484 if (!queue) {
1485 error("Error allocating constructor queue: %m\n");
1486 if (runtime) longjmp(*rtld_fail, 1);
1487 return 0;
1488 }
1489
1490 /* Opposite ends of the allocated buffer serve as an output queue
1491 * and a working stack. Setup initial stack with just the argument
1492 * dso and initial queue empty... */
1493 stack = queue;
1494 qpos = 0;
1495 spos = cnt;
1496 stack[--spos] = dso;
1497 dso->next_dep = 0;
1498 dso->mark = 1;
1499
1500 /* Then perform pseudo-DFS sort, but ignoring circular deps. */
1501 while (spos<cnt) {
1502 p = stack[spos++];
1503 while (p->next_dep < p->ndeps_direct) {
1504 if (p->deps[p->next_dep]->mark) {
1505 p->next_dep++;
1506 } else {
1507 stack[--spos] = p;
1508 p = p->deps[p->next_dep];
1509 p->next_dep = 0;
1510 p->mark = 1;
1511 }
1512 }
1513 queue[qpos++] = p;
1514 }
1515 queue[qpos] = 0;
1516 for (i=0; i<qpos; i++) queue[i]->mark = 0;
1517 for (i=0; i<qpos; i++)
1518 if (queue[i]->ctor_visitor && queue[i]->ctor_visitor->tid < 0) {
1519 error("State of %s is inconsistent due to multithreaded fork\n",
1520 queue[i]->name);
1521 free(queue);
1522 if (runtime) longjmp(*rtld_fail, 1);
1523 }
1524
1525 return queue;
1526 }
1527
do_init_fini(struct dso ** queue)1528 static void do_init_fini(struct dso **queue)
1529 {
1530 struct dso *p;
1531 size_t dyn[DYN_CNT], i;
1532 pthread_t self = __pthread_self();
1533
1534 pthread_mutex_lock(&init_fini_lock);
1535 for (i=0; (p=queue[i]); i++) {
1536 while ((p->ctor_visitor && p->ctor_visitor!=self) || shutting_down)
1537 pthread_cond_wait(&ctor_cond, &init_fini_lock);
1538 if (p->ctor_visitor || p->constructed)
1539 continue;
1540 p->ctor_visitor = self;
1541
1542 decode_vec(p->dynv, dyn, DYN_CNT);
1543 if (dyn[0] & ((1<<DT_FINI) | (1<<DT_FINI_ARRAY))) {
1544 p->fini_next = fini_head;
1545 fini_head = p;
1546 }
1547
1548 pthread_mutex_unlock(&init_fini_lock);
1549
1550 #ifndef NO_LEGACY_INITFINI
1551 if ((dyn[0] & (1<<DT_INIT)) && dyn[DT_INIT])
1552 fpaddr(p, dyn[DT_INIT])();
1553 #endif
1554 if (dyn[0] & (1<<DT_INIT_ARRAY)) {
1555 size_t n = dyn[DT_INIT_ARRAYSZ]/sizeof(size_t);
1556 size_t *fn = laddr(p, dyn[DT_INIT_ARRAY]);
1557 while (n--) ((void (*)(void))*fn++)();
1558 }
1559
1560 pthread_mutex_lock(&init_fini_lock);
1561 p->ctor_visitor = 0;
1562 p->constructed = 1;
1563 pthread_cond_broadcast(&ctor_cond);
1564 }
1565 pthread_mutex_unlock(&init_fini_lock);
1566 }
1567
__libc_start_init(void)1568 void __libc_start_init(void)
1569 {
1570 do_init_fini(main_ctor_queue);
1571 if (!__malloc_replaced && main_ctor_queue != builtin_ctor_queue)
1572 free(main_ctor_queue);
1573 main_ctor_queue = 0;
1574 }
1575
dl_debug_state(void)1576 static void dl_debug_state(void)
1577 {
1578 }
1579
1580 weak_alias(dl_debug_state, _dl_debug_state);
1581
__init_tls(size_t * auxv)1582 void __init_tls(size_t *auxv)
1583 {
1584 }
1585
update_tls_size()1586 static void update_tls_size()
1587 {
1588 libc.tls_cnt = tls_cnt;
1589 libc.tls_align = tls_align;
1590 libc.tls_size = ALIGN(
1591 (1+tls_cnt) * sizeof(void *) +
1592 tls_offset +
1593 sizeof(struct pthread) +
1594 tls_align * 2,
1595 tls_align);
1596 }
1597
install_new_tls(void)1598 static void install_new_tls(void)
1599 {
1600 sigset_t set;
1601 pthread_t self = __pthread_self(), td;
1602 struct dso *dtv_provider = container_of(tls_tail, struct dso, tls);
1603 uintptr_t (*newdtv)[tls_cnt+1] = (void *)dtv_provider->new_dtv;
1604 struct dso *p;
1605 size_t i, j;
1606 size_t old_cnt = self->dtv[0];
1607
1608 __block_app_sigs(&set);
1609 __tl_lock();
1610 /* Copy existing dtv contents from all existing threads. */
1611 for (i=0, td=self; !i || td!=self; i++, td=td->next) {
1612 memcpy(newdtv+i, td->dtv,
1613 (old_cnt+1)*sizeof(uintptr_t));
1614 newdtv[i][0] = tls_cnt;
1615 }
1616 /* Install new dtls into the enlarged, uninstalled dtv copies. */
1617 for (p=head; ; p=p->next) {
1618 if (p->tls_id <= old_cnt) continue;
1619 unsigned char *mem = p->new_tls;
1620 for (j=0; j<i; j++) {
1621 unsigned char *new = mem;
1622 new += ((uintptr_t)p->tls.image - (uintptr_t)mem)
1623 & (p->tls.align-1);
1624 memcpy(new, p->tls.image, p->tls.len);
1625 newdtv[j][p->tls_id] =
1626 (uintptr_t)new + DTP_OFFSET;
1627 mem += p->tls.size + p->tls.align;
1628 }
1629 if (p->tls_id == tls_cnt) break;
1630 }
1631
1632 /* Broadcast barrier to ensure contents of new dtv is visible
1633 * if the new dtv pointer is. The __membarrier function has a
1634 * fallback emulation using signals for kernels that lack the
1635 * feature at the syscall level. */
1636
1637 __membarrier(MEMBARRIER_CMD_PRIVATE_EXPEDITED, 0);
1638
1639 /* Install new dtv for each thread. */
1640 for (j=0, td=self; !j || td!=self; j++, td=td->next) {
1641 td->dtv = newdtv[j];
1642 }
1643
1644 __tl_unlock();
1645 __restore_sigs(&set);
1646 }
1647
1648 /* Stage 1 of the dynamic linker is defined in dlstart.c. It calls the
1649 * following stage 2 and stage 3 functions via primitive symbolic lookup
1650 * since it does not have access to their addresses to begin with. */
1651
1652 /* Stage 2 of the dynamic linker is called after relative relocations
1653 * have been processed. It can make function calls to static functions
1654 * and access string literals and static data, but cannot use extern
1655 * symbols. Its job is to perform symbolic relocations on the dynamic
1656 * linker itself, but some of the relocations performed may need to be
1657 * replaced later due to copy relocations in the main program. */
1658
__dls2(unsigned char * base,size_t * sp)1659 hidden void __dls2(unsigned char *base, size_t *sp)
1660 {
1661 size_t *auxv;
1662 for (auxv=sp+1+*sp+1; *auxv; auxv++);
1663 auxv++;
1664 if (DL_FDPIC) {
1665 void *p1 = (void *)sp[-2];
1666 void *p2 = (void *)sp[-1];
1667 if (!p1) {
1668 size_t aux[AUX_CNT];
1669 decode_vec(auxv, aux, AUX_CNT);
1670 if (aux[AT_BASE]) ldso.base = (void *)aux[AT_BASE];
1671 else ldso.base = (void *)(aux[AT_PHDR] & -4096);
1672 }
1673 app_loadmap = p2 ? p1 : 0;
1674 ldso.loadmap = p2 ? p2 : p1;
1675 ldso.base = laddr(&ldso, 0);
1676 } else {
1677 ldso.base = base;
1678 }
1679 Ehdr *ehdr = (void *)ldso.base;
1680 ldso.name = ldso.shortname = "libc.so";
1681 ldso.phnum = ehdr->e_phnum;
1682 ldso.phdr = laddr(&ldso, ehdr->e_phoff);
1683 ldso.phentsize = ehdr->e_phentsize;
1684 kernel_mapped_dso(&ldso);
1685 decode_dyn(&ldso);
1686
1687 if (DL_FDPIC) makefuncdescs(&ldso);
1688
1689 /* Prepare storage for to save clobbered REL addends so they
1690 * can be reused in stage 3. There should be very few. If
1691 * something goes wrong and there are a huge number, abort
1692 * instead of risking stack overflow. */
1693 size_t dyn[DYN_CNT];
1694 decode_vec(ldso.dynv, dyn, DYN_CNT);
1695 size_t *rel = laddr(&ldso, dyn[DT_REL]);
1696 size_t rel_size = dyn[DT_RELSZ];
1697 size_t symbolic_rel_cnt = 0;
1698 apply_addends_to = rel;
1699 for (; rel_size; rel+=2, rel_size-=2*sizeof(size_t))
1700 if (!IS_RELATIVE(rel[1], ldso.syms)) symbolic_rel_cnt++;
1701 if (symbolic_rel_cnt >= ADDEND_LIMIT) a_crash();
1702 size_t addends[symbolic_rel_cnt+1];
1703 saved_addends = addends;
1704
1705 head = &ldso;
1706 reloc_all(&ldso);
1707
1708 ldso.relocated = 0;
1709
1710 /* Call dynamic linker stage-2b, __dls2b, looking it up
1711 * symbolically as a barrier against moving the address
1712 * load across the above relocation processing. */
1713 struct symdef dls2b_def = find_sym(&ldso, "__dls2b", 0);
1714 if (DL_FDPIC) ((stage3_func)&ldso.funcdescs[dls2b_def.sym-ldso.syms])(sp, auxv);
1715 else ((stage3_func)laddr(&ldso, dls2b_def.sym->st_value))(sp, auxv);
1716 }
1717
1718 /* Stage 2b sets up a valid thread pointer, which requires relocations
1719 * completed in stage 2, and on which stage 3 is permitted to depend.
1720 * This is done as a separate stage, with symbolic lookup as a barrier,
1721 * so that loads of the thread pointer and &errno can be pure/const and
1722 * thereby hoistable. */
1723
__dls2b(size_t * sp,size_t * auxv)1724 void __dls2b(size_t *sp, size_t *auxv)
1725 {
1726 /* Setup early thread pointer in builtin_tls for ldso/libc itself to
1727 * use during dynamic linking. If possible it will also serve as the
1728 * thread pointer at runtime. */
1729 search_vec(auxv, &__hwcap, AT_HWCAP);
1730 libc.auxv = auxv;
1731 libc.tls_size = sizeof builtin_tls;
1732 libc.tls_align = tls_align;
1733 if (__init_tp(__copy_tls((void *)builtin_tls)) < 0) {
1734 a_crash();
1735 }
1736
1737 struct symdef dls3_def = find_sym(&ldso, "__dls3", 0);
1738 if (DL_FDPIC) ((stage3_func)&ldso.funcdescs[dls3_def.sym-ldso.syms])(sp, auxv);
1739 else ((stage3_func)laddr(&ldso, dls3_def.sym->st_value))(sp, auxv);
1740 }
1741
1742 /* Stage 3 of the dynamic linker is called with the dynamic linker/libc
1743 * fully functional. Its job is to load (if not already loaded) and
1744 * process dependencies and relocations for the main application and
1745 * transfer control to its entry point. */
1746
__dls3(size_t * sp,size_t * auxv)1747 void __dls3(size_t *sp, size_t *auxv)
1748 {
1749 static struct dso app, vdso;
1750 size_t aux[AUX_CNT];
1751 size_t i;
1752 char *env_preload=0;
1753 char *replace_argv0=0;
1754 size_t vdso_base;
1755 int argc = *sp;
1756 char **argv = (void *)(sp+1);
1757 char **argv_orig = argv;
1758 char **envp = argv+argc+1;
1759
1760 /* Find aux vector just past environ[] and use it to initialize
1761 * global data that may be needed before we can make syscalls. */
1762 __environ = envp;
1763 decode_vec(auxv, aux, AUX_CNT);
1764 search_vec(auxv, &__sysinfo, AT_SYSINFO);
1765 __pthread_self()->sysinfo = __sysinfo;
1766 libc.page_size = aux[AT_PAGESZ];
1767 libc.secure = ((aux[0]&0x7800)!=0x7800 || aux[AT_UID]!=aux[AT_EUID]
1768 || aux[AT_GID]!=aux[AT_EGID] || aux[AT_SECURE]);
1769
1770 /* Only trust user/env if kernel says we're not suid/sgid */
1771 if (!libc.secure) {
1772 env_path = getenv("LD_LIBRARY_PATH");
1773 env_preload = getenv("LD_PRELOAD");
1774 }
1775
1776 /* If the main program was already loaded by the kernel,
1777 * AT_PHDR will point to some location other than the dynamic
1778 * linker's program headers. */
1779 if (aux[AT_PHDR] != (size_t)ldso.phdr) {
1780 size_t interp_off = 0;
1781 size_t tls_image = 0;
1782 /* Find load address of the main program, via AT_PHDR vs PT_PHDR. */
1783 Phdr *phdr = app.phdr = (void *)aux[AT_PHDR];
1784 app.phnum = aux[AT_PHNUM];
1785 app.phentsize = aux[AT_PHENT];
1786 for (i=aux[AT_PHNUM]; i; i--, phdr=(void *)((char *)phdr + aux[AT_PHENT])) {
1787 if (phdr->p_type == PT_PHDR)
1788 app.base = (void *)(aux[AT_PHDR] - phdr->p_vaddr);
1789 else if (phdr->p_type == PT_INTERP)
1790 interp_off = (size_t)phdr->p_vaddr;
1791 else if (phdr->p_type == PT_TLS) {
1792 tls_image = phdr->p_vaddr;
1793 app.tls.len = phdr->p_filesz;
1794 app.tls.size = phdr->p_memsz;
1795 app.tls.align = phdr->p_align;
1796 }
1797 }
1798 if (DL_FDPIC) app.loadmap = app_loadmap;
1799 if (app.tls.size) app.tls.image = laddr(&app, tls_image);
1800 if (interp_off) ldso.name = laddr(&app, interp_off);
1801 #if 0
1802 if ((aux[0] & (1UL<<AT_EXECFN))
1803 && strncmp((char *)aux[AT_EXECFN], "/proc/", 6))
1804 app.name = (char *)aux[AT_EXECFN];
1805 else
1806 app.name = argv[0];
1807 #else
1808 if (argv[0])
1809 app.name = argv[0];
1810 else
1811 app.name = "none";
1812 #endif
1813 kernel_mapped_dso(&app);
1814 } else {
1815 int fd;
1816 char *ldname = argv[0];
1817 size_t l = strlen(ldname);
1818 if (l >= 3 && !strcmp(ldname+l-3, "ldd")) ldd_mode = 1;
1819 argv++;
1820 while (argv[0] && argv[0][0]=='-' && argv[0][1]=='-') {
1821 char *opt = argv[0]+2;
1822 *argv++ = (void *)-1;
1823 if (!*opt) {
1824 break;
1825 } else if (!memcmp(opt, "list", 5)) {
1826 ldd_mode = 1;
1827 } else if (!memcmp(opt, "library-path", 12)) {
1828 if (opt[12]=='=') env_path = opt+13;
1829 else if (opt[12]) *argv = 0;
1830 else if (*argv) env_path = *argv++;
1831 } else if (!memcmp(opt, "preload", 7)) {
1832 if (opt[7]=='=') env_preload = opt+8;
1833 else if (opt[7]) *argv = 0;
1834 else if (*argv) env_preload = *argv++;
1835 } else if (!memcmp(opt, "argv0", 5)) {
1836 if (opt[5]=='=') replace_argv0 = opt+6;
1837 else if (opt[5]) *argv = 0;
1838 else if (*argv) replace_argv0 = *argv++;
1839 } else {
1840 argv[0] = 0;
1841 }
1842 }
1843 argv[-1] = (void *)(argc - (argv-argv_orig));
1844 if (!argv[0]) {
1845 dprintf(2, "musl libc (" LDSO_ARCH ")\n"
1846 "Version %s\n"
1847 "Dynamic Program Loader\n"
1848 "Usage: %s [options] [--] pathname%s\n",
1849 __libc_version, ldname,
1850 ldd_mode ? "" : " [args]");
1851 _exit(1);
1852 }
1853 fd = open(argv[0], O_RDONLY);
1854 if (fd < 0) {
1855 dprintf(2, "%s: cannot load %s: %s\n", ldname, argv[0], strerror(errno));
1856 _exit(1);
1857 }
1858 Ehdr *ehdr = map_library(fd, &app);
1859 if (!ehdr) {
1860 dprintf(2, "%s: %s: Not a valid dynamic program\n", ldname, argv[0]);
1861 _exit(1);
1862 }
1863 close(fd);
1864 ldso.name = ldname;
1865 app.name = argv[0];
1866 aux[AT_ENTRY] = (size_t)laddr(&app, ehdr->e_entry);
1867 /* Find the name that would have been used for the dynamic
1868 * linker had ldd not taken its place. */
1869 if (ldd_mode) {
1870 for (i=0; i<app.phnum; i++) {
1871 if (app.phdr[i].p_type == PT_INTERP)
1872 ldso.name = laddr(&app, app.phdr[i].p_vaddr);
1873 }
1874 dprintf(1, "\t%s (%p)\n", ldso.name, ldso.base);
1875 }
1876 }
1877 if (app.tls.size) {
1878 libc.tls_head = tls_tail = &app.tls;
1879 app.tls_id = tls_cnt = 1;
1880 #ifdef TLS_ABOVE_TP
1881 app.tls.offset = GAP_ABOVE_TP;
1882 app.tls.offset += (-GAP_ABOVE_TP + (uintptr_t)app.tls.image)
1883 & (app.tls.align-1);
1884 tls_offset = app.tls.offset + app.tls.size;
1885 #else
1886 tls_offset = app.tls.offset = app.tls.size
1887 + ( -((uintptr_t)app.tls.image + app.tls.size)
1888 & (app.tls.align-1) );
1889 #endif
1890 tls_align = MAXP2(tls_align, app.tls.align);
1891 }
1892 decode_dyn(&app);
1893 if (DL_FDPIC) {
1894 makefuncdescs(&app);
1895 if (!app.loadmap) {
1896 app.loadmap = (void *)&app_dummy_loadmap;
1897 app.loadmap->nsegs = 1;
1898 app.loadmap->segs[0].addr = (size_t)app.map;
1899 app.loadmap->segs[0].p_vaddr = (size_t)app.map
1900 - (size_t)app.base;
1901 app.loadmap->segs[0].p_memsz = app.map_len;
1902 }
1903 argv[-3] = (void *)app.loadmap;
1904 }
1905
1906 /* Initial dso chain consists only of the app. */
1907 head = tail = syms_tail = &app;
1908
1909 /* Donate unused parts of app and library mapping to malloc */
1910 reclaim_gaps(&app);
1911 reclaim_gaps(&ldso);
1912
1913 /* Load preload/needed libraries, add symbols to global namespace. */
1914 ldso.deps = (struct dso **)no_deps;
1915 if (env_preload) load_preload(env_preload);
1916 load_deps(&app);
1917 for (struct dso *p=head; p; p=p->next)
1918 add_syms(p);
1919
1920 /* Attach to vdso, if provided by the kernel, last so that it does
1921 * not become part of the global namespace. */
1922 if (search_vec(auxv, &vdso_base, AT_SYSINFO_EHDR) && vdso_base) {
1923 Ehdr *ehdr = (void *)vdso_base;
1924 Phdr *phdr = vdso.phdr = (void *)(vdso_base + ehdr->e_phoff);
1925 vdso.phnum = ehdr->e_phnum;
1926 vdso.phentsize = ehdr->e_phentsize;
1927 for (i=ehdr->e_phnum; i; i--, phdr=(void *)((char *)phdr + ehdr->e_phentsize)) {
1928 if (phdr->p_type == PT_DYNAMIC)
1929 vdso.dynv = (void *)(vdso_base + phdr->p_offset);
1930 if (phdr->p_type == PT_LOAD)
1931 vdso.base = (void *)(vdso_base - phdr->p_vaddr + phdr->p_offset);
1932 }
1933 vdso.name = "";
1934 vdso.shortname = "OHOS-vdso.so";
1935 vdso.relocated = 1;
1936 vdso.deps = (struct dso **)no_deps;
1937 decode_dyn(&vdso);
1938 vdso.prev = tail;
1939 tail->next = &vdso;
1940 tail = &vdso;
1941 }
1942
1943 for (i=0; app.dynv[i]; i+=2) {
1944 if (!DT_DEBUG_INDIRECT && app.dynv[i]==DT_DEBUG)
1945 app.dynv[i+1] = (size_t)&debug;
1946 if (DT_DEBUG_INDIRECT && app.dynv[i]==DT_DEBUG_INDIRECT) {
1947 size_t *ptr = (size_t *) app.dynv[i+1];
1948 *ptr = (size_t)&debug;
1949 }
1950 }
1951
1952 /* This must be done before final relocations, since it calls
1953 * malloc, which may be provided by the application. Calling any
1954 * application code prior to the jump to its entry point is not
1955 * valid in our model and does not work with FDPIC, where there
1956 * are additional relocation-like fixups that only the entry point
1957 * code can see to perform. */
1958 main_ctor_queue = queue_ctors(&app);
1959
1960 /* Initial TLS must also be allocated before final relocations
1961 * might result in calloc being a call to application code. */
1962 update_tls_size();
1963 void *initial_tls = builtin_tls;
1964 if (libc.tls_size > sizeof builtin_tls || tls_align > MIN_TLS_ALIGN) {
1965 initial_tls = calloc(libc.tls_size, 1);
1966 if (!initial_tls) {
1967 dprintf(2, "%s: Error getting %zu bytes thread-local storage: %m\n",
1968 argv[0], libc.tls_size);
1969 _exit(127);
1970 }
1971 }
1972 static_tls_cnt = tls_cnt;
1973
1974 /* The main program must be relocated LAST since it may contain
1975 * copy relocations which depend on libraries' relocations. */
1976 reloc_all(app.next);
1977 reloc_all(&app);
1978
1979 /* Actual copying to new TLS needs to happen after relocations,
1980 * since the TLS images might have contained relocated addresses. */
1981 if (initial_tls != builtin_tls) {
1982 if (__init_tp(__copy_tls(initial_tls)) < 0) {
1983 a_crash();
1984 }
1985 } else {
1986 size_t tmp_tls_size = libc.tls_size;
1987 pthread_t self = __pthread_self();
1988 /* Temporarily set the tls size to the full size of
1989 * builtin_tls so that __copy_tls will use the same layout
1990 * as it did for before. Then check, just to be safe. */
1991 libc.tls_size = sizeof builtin_tls;
1992 if (__copy_tls((void*)builtin_tls) != self) a_crash();
1993 libc.tls_size = tmp_tls_size;
1994 }
1995
1996 if (ldso_fail) _exit(127);
1997 if (ldd_mode) _exit(0);
1998
1999 /* Determine if malloc was interposed by a replacement implementation
2000 * so that calloc and the memalign family can harden against the
2001 * possibility of incomplete replacement. */
2002 if (find_sym(head, "malloc", 1).dso != &ldso)
2003 __malloc_replaced = 1;
2004 if (find_sym(head, "aligned_alloc", 1).dso != &ldso)
2005 __aligned_alloc_replaced = 1;
2006
2007 /* Switch to runtime mode: any further failures in the dynamic
2008 * linker are a reportable failure rather than a fatal startup
2009 * error. */
2010 runtime = 1;
2011
2012 debug.ver = 1;
2013 debug.bp = dl_debug_state;
2014 debug.head = head;
2015 debug.base = ldso.base;
2016 debug.state = RT_CONSISTENT;
2017 _dl_debug_state();
2018
2019 if (replace_argv0) argv[0] = replace_argv0;
2020
2021 errno = 0;
2022
2023 CRTJMP((void *)aux[AT_ENTRY], argv-1);
2024 for(;;);
2025 }
2026
prepare_lazy(struct dso * p)2027 static void prepare_lazy(struct dso *p)
2028 {
2029 size_t dyn[DYN_CNT], n, flags1=0;
2030 decode_vec(p->dynv, dyn, DYN_CNT);
2031 search_vec(p->dynv, &flags1, DT_FLAGS_1);
2032 if (dyn[DT_BIND_NOW] || (dyn[DT_FLAGS] & DF_BIND_NOW) || (flags1 & DF_1_NOW))
2033 return;
2034 n = dyn[DT_RELSZ]/2 + dyn[DT_RELASZ]/3 + dyn[DT_PLTRELSZ]/2 + 1;
2035 if (NEED_MIPS_GOT_RELOCS) {
2036 size_t j=0; search_vec(p->dynv, &j, DT_MIPS_GOTSYM);
2037 size_t i=0; search_vec(p->dynv, &i, DT_MIPS_SYMTABNO);
2038 n += i-j;
2039 }
2040 p->lazy = calloc(n, 3*sizeof(size_t));
2041 if (!p->lazy) {
2042 error("Error preparing lazy relocation for %s: %m", p->name);
2043 longjmp(*rtld_fail, 1);
2044 }
2045 p->lazy_next = lazy_head;
2046 lazy_head = p;
2047 }
2048
dlopen(const char * file,int mode)2049 void *dlopen(const char *file, int mode)
2050 {
2051 struct dso *volatile p, *orig_tail, *orig_syms_tail, *orig_lazy_head, *next;
2052 struct tls_module *orig_tls_tail;
2053 size_t orig_tls_cnt, orig_tls_offset, orig_tls_align;
2054 size_t i;
2055 int cs;
2056 jmp_buf jb;
2057 struct dso **volatile ctor_queue = 0;
2058
2059 if (mode & ~(RTLD_LAZY | RTLD_NOW | RTLD_NOLOAD | RTLD_GLOBAL | RTLD_LOCAL | RTLD_NODELETE)) {
2060 error("invalid mode parameter for dlopen().");
2061 return NULL;
2062 }
2063
2064 if ((mode & (RTLD_LAZY | RTLD_NOW)) == 0) {
2065 error("invalid mode, one of RTLD_LAZY and RTLD_NOW must be set.");
2066 return NULL;
2067 }
2068
2069 if (!file) return head;
2070
2071 pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
2072 pthread_rwlock_wrlock(&lock);
2073 __inhibit_ptc();
2074
2075 debug.state = RT_ADD;
2076 _dl_debug_state();
2077
2078 p = 0;
2079 if (shutting_down) {
2080 error("Cannot dlopen while program is exiting.");
2081 goto end;
2082 }
2083 orig_tls_tail = tls_tail;
2084 orig_tls_cnt = tls_cnt;
2085 orig_tls_offset = tls_offset;
2086 orig_tls_align = tls_align;
2087 orig_lazy_head = lazy_head;
2088 orig_syms_tail = syms_tail;
2089 orig_tail = tail;
2090 noload = mode & RTLD_NOLOAD;
2091
2092 rtld_fail = &jb;
2093 if (setjmp(*rtld_fail)) {
2094 /* Clean up anything new that was (partially) loaded */
2095 revert_syms(orig_syms_tail);
2096 for (p=orig_tail->next; p; p=next) {
2097 next = p->next;
2098 while (p->td_index) {
2099 void *tmp = p->td_index->next;
2100 free(p->td_index);
2101 p->td_index = tmp;
2102 }
2103 free(p->funcdescs);
2104 if (p->rpath != p->rpath_orig)
2105 free(p->rpath);
2106 free(p->deps);
2107 unmap_library(p);
2108 free(p);
2109 }
2110 free(ctor_queue);
2111 ctor_queue = 0;
2112 if (!orig_tls_tail) libc.tls_head = 0;
2113 tls_tail = orig_tls_tail;
2114 if (tls_tail) tls_tail->next = 0;
2115 tls_cnt = orig_tls_cnt;
2116 tls_offset = orig_tls_offset;
2117 tls_align = orig_tls_align;
2118 lazy_head = orig_lazy_head;
2119 tail = orig_tail;
2120 tail->next = 0;
2121 p = 0;
2122 goto end;
2123 } else p = load_library(file, head);
2124
2125 if (!p) {
2126 error(noload ?
2127 "Library %s is not already loaded" :
2128 "Error loading shared library %s: %m",
2129 file);
2130 goto end;
2131 }
2132
2133 /* First load handling */
2134 load_deps(p);
2135 extend_bfs_deps(p);
2136 pthread_mutex_lock(&init_fini_lock);
2137 int constructed = p->constructed;
2138 pthread_mutex_unlock(&init_fini_lock);
2139 if (!constructed) ctor_queue = queue_ctors(p);
2140 if (!p->relocated && (mode & RTLD_LAZY)) {
2141 prepare_lazy(p);
2142 for (i=0; p->deps[i]; i++)
2143 if (!p->deps[i]->relocated)
2144 prepare_lazy(p->deps[i]);
2145 }
2146 if (!p->relocated || (mode & RTLD_GLOBAL)) {
2147 /* Make new symbols global, at least temporarily, so we can do
2148 * relocations. If not RTLD_GLOBAL, this is reverted below. */
2149 add_syms(p);
2150 for (i=0; p->deps[i]; i++)
2151 add_syms(p->deps[i]);
2152 }
2153 if (!p->relocated) {
2154 reloc_all(p);
2155 }
2156
2157 /* If RTLD_GLOBAL was not specified, undo any new additions
2158 * to the global symbol table. This is a nop if the library was
2159 * previously loaded and already global. */
2160 if (!(mode & RTLD_GLOBAL))
2161 revert_syms(orig_syms_tail);
2162
2163 /* Processing of deferred lazy relocations must not happen until
2164 * the new libraries are committed; otherwise we could end up with
2165 * relocations resolved to symbol definitions that get removed. */
2166 redo_lazy_relocs();
2167
2168 update_tls_size();
2169 if (tls_cnt != orig_tls_cnt)
2170 install_new_tls();
2171 orig_tail = tail;
2172 end:
2173 debug.state = RT_CONSISTENT;
2174 _dl_debug_state();
2175 __release_ptc();
2176 if (p) gencnt++;
2177 pthread_rwlock_unlock(&lock);
2178 if (ctor_queue) {
2179 do_init_fini(ctor_queue);
2180 free(ctor_queue);
2181 }
2182 pthread_setcancelstate(cs, 0);
2183 return p;
2184 }
2185
__dl_invalid_handle(void * h)2186 hidden int __dl_invalid_handle(void *h)
2187 {
2188 struct dso *p;
2189 for (p=head; p; p=p->next) if (h==p) return 0;
2190 error("Invalid library handle %p", (void *)h);
2191 return 1;
2192 }
2193
addr2dso(size_t a)2194 static void *addr2dso(size_t a)
2195 {
2196 struct dso *p;
2197 size_t i;
2198 if (DL_FDPIC) for (p=head; p; p=p->next) {
2199 i = count_syms(p);
2200 if (a-(size_t)p->funcdescs < i*sizeof(*p->funcdescs))
2201 return p;
2202 }
2203 for (p=head; p; p=p->next) {
2204 if (DL_FDPIC && p->loadmap) {
2205 for (i=0; i<p->loadmap->nsegs; i++) {
2206 if (a-p->loadmap->segs[i].p_vaddr
2207 < p->loadmap->segs[i].p_memsz)
2208 return p;
2209 }
2210 } else {
2211 Phdr *ph = p->phdr;
2212 size_t phcnt = p->phnum;
2213 size_t entsz = p->phentsize;
2214 size_t base = (size_t)p->base;
2215 for (; phcnt--; ph=(void *)((char *)ph+entsz)) {
2216 if (ph->p_type != PT_LOAD) continue;
2217 if (a-base-ph->p_vaddr < ph->p_memsz)
2218 return p;
2219 }
2220 if (a-(size_t)p->map < p->map_len)
2221 return 0;
2222 }
2223 }
2224 return 0;
2225 }
2226
do_dlsym(struct dso * p,const char * s,void * ra)2227 static void *do_dlsym(struct dso *p, const char *s, void *ra)
2228 {
2229 int use_deps = 0;
2230 if (p == head || p == RTLD_DEFAULT) {
2231 p = head;
2232 } else if (p == RTLD_NEXT) {
2233 p = addr2dso((size_t)ra);
2234 if (!p) p=head;
2235 p = p->next;
2236 } else if (__dl_invalid_handle(p)) {
2237 return 0;
2238 } else
2239 use_deps = 1;
2240 struct symdef def = find_sym2(p, s, 0, use_deps);
2241 if (!def.sym) {
2242 error("Symbol not found: %s", s);
2243 return 0;
2244 }
2245 if ((def.sym->st_info&0xf) == STT_TLS)
2246 return __tls_get_addr((tls_mod_off_t []){def.dso->tls_id, def.sym->st_value-DTP_OFFSET});
2247 if (DL_FDPIC && (def.sym->st_info&0xf) == STT_FUNC)
2248 return def.dso->funcdescs + (def.sym - def.dso->syms);
2249 return laddr(def.dso, def.sym->st_value);
2250 }
2251
dladdr(const void * addr_arg,Dl_info * info)2252 int dladdr(const void *addr_arg, Dl_info *info)
2253 {
2254 size_t addr = (size_t)addr_arg;
2255 struct dso *p;
2256 Sym *sym, *bestsym;
2257 uint32_t nsym;
2258 char *strings;
2259 size_t best = 0;
2260 size_t besterr = -1;
2261
2262 pthread_rwlock_rdlock(&lock);
2263 p = addr2dso(addr);
2264 pthread_rwlock_unlock(&lock);
2265
2266 if (!p) return 0;
2267
2268 sym = p->syms;
2269 strings = p->strings;
2270 nsym = count_syms(p);
2271
2272 if (DL_FDPIC) {
2273 size_t idx = (addr-(size_t)p->funcdescs)
2274 / sizeof(*p->funcdescs);
2275 if (idx < nsym && (sym[idx].st_info&0xf) == STT_FUNC) {
2276 best = (size_t)(p->funcdescs + idx);
2277 bestsym = sym + idx;
2278 besterr = 0;
2279 }
2280 }
2281
2282 if (!best) for (; nsym; nsym--, sym++) {
2283 if (sym->st_value
2284 && (1<<(sym->st_info&0xf) & OK_TYPES)
2285 && (1<<(sym->st_info>>4) & OK_BINDS)) {
2286 size_t symaddr = (size_t)laddr(p, sym->st_value);
2287 if (symaddr > addr || symaddr <= best)
2288 continue;
2289 best = symaddr;
2290 bestsym = sym;
2291 besterr = addr - symaddr;
2292 if (addr == symaddr)
2293 break;
2294 }
2295 }
2296
2297 if (best && besterr > bestsym->st_size-1) {
2298 best = 0;
2299 bestsym = 0;
2300 }
2301
2302 info->dli_fname = p->name;
2303 info->dli_fbase = p->map;
2304
2305 if (!best) {
2306 info->dli_sname = 0;
2307 info->dli_saddr = 0;
2308 return 1;
2309 }
2310
2311 if (DL_FDPIC && (bestsym->st_info&0xf) == STT_FUNC)
2312 best = (size_t)(p->funcdescs + (bestsym - p->syms));
2313 info->dli_sname = strings + bestsym->st_name;
2314 info->dli_saddr = (void *)best;
2315
2316 return 1;
2317 }
2318
__dlsym(void * restrict p,const char * restrict s,void * restrict ra)2319 hidden void *__dlsym(void *restrict p, const char *restrict s, void *restrict ra)
2320 {
2321 void *res;
2322 pthread_rwlock_rdlock(&lock);
2323 res = do_dlsym(p, s, ra);
2324 pthread_rwlock_unlock(&lock);
2325 return res;
2326 }
2327
__dlsym_redir_time64(void * restrict p,const char * restrict s,void * restrict ra)2328 hidden void *__dlsym_redir_time64(void *restrict p, const char *restrict s, void *restrict ra)
2329 {
2330 #if _REDIR_TIME64
2331 const char *suffix, *suffix2 = "";
2332 char redir[36];
2333
2334 /* Map the symbol name to a time64 version of itself according to the
2335 * pattern used for naming the redirected time64 symbols. */
2336 size_t l = strnlen(s, sizeof redir);
2337 if (l<4 || l==sizeof redir) goto no_redir;
2338 if (s[l-2]=='_' && s[l-1]=='r') {
2339 l -= 2;
2340 suffix2 = s+l;
2341 }
2342 if (l<4) goto no_redir;
2343 if (!strcmp(s+l-4, "time")) suffix = "64";
2344 else suffix = "_time64";
2345
2346 /* Use the presence of the remapped symbol name in libc to determine
2347 * whether it's one that requires time64 redirection; replace if so. */
2348 snprintf(redir, sizeof redir, "__%.*s%s%s", (int)l, s, suffix, suffix2);
2349 if (find_sym(&ldso, redir, 1).sym) s = redir;
2350 no_redir:
2351 #endif
2352 return __dlsym(p, s, ra);
2353 }
2354
dl_iterate_phdr(int (* callback)(struct dl_phdr_info * info,size_t size,void * data),void * data)2355 int dl_iterate_phdr(int(*callback)(struct dl_phdr_info *info, size_t size, void *data), void *data)
2356 {
2357 struct dso *current;
2358 struct dl_phdr_info info;
2359 int ret = 0;
2360 for(current = head; current;) {
2361 info.dlpi_addr = (uintptr_t)current->base;
2362 info.dlpi_name = current->name;
2363 info.dlpi_phdr = current->phdr;
2364 info.dlpi_phnum = current->phnum;
2365 info.dlpi_adds = gencnt;
2366 info.dlpi_subs = 0;
2367 info.dlpi_tls_modid = current->tls_id;
2368 info.dlpi_tls_data = !current->tls_id ? 0 :
2369 __tls_get_addr((tls_mod_off_t[]){current->tls_id,0});
2370
2371 ret = (callback)(&info, sizeof (info), data);
2372
2373 if (ret != 0) break;
2374
2375 pthread_rwlock_rdlock(&lock);
2376 current = current->next;
2377 pthread_rwlock_unlock(&lock);
2378 }
2379 return ret;
2380 }
2381
error(const char * fmt,...)2382 static void error(const char *fmt, ...)
2383 {
2384 va_list ap;
2385 va_start(ap, fmt);
2386 if (!runtime) {
2387 vdprintf(2, fmt, ap);
2388 dprintf(2, "\n");
2389 ldso_fail = 1;
2390 va_end(ap);
2391 return;
2392 }
2393 __dl_vseterr(fmt, ap);
2394 va_end(ap);
2395 }
2396