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

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