nsz Git - musl/blob - ldso/dynlink.c

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