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

   1 #define _GNU_SOURCE
   2 #include <stdio.h>
   3 #include <stdlib.h>
   4 #include <string.h>
   5 #include <unistd.h>
   6 #include <stdint.h>
   7 #include <elf.h>
   8 #include <sys/mman.h>
   9 #include <limits.h>
  10 #include <stdint.h>
  11 #include <fcntl.h>
  12 #include <sys/stat.h>
  13 #include <errno.h>
  14 #include <limits.h>
  15 #include <elf.h>
  16 #include <link.h>
  17 #include <setjmp.h>
  18 #include <pthread.h>
  19 #include <ctype.h>
  20 #include <dlfcn.h>
  21 #include "pthread_impl.h"
  22 #include "libc.h"
  23
  24 static int errflag;
  25 static char errbuf[128];
  26
  27 #ifdef SHARED
  28
  29 #if ULONG_MAX == 0xffffffff
  30 typedef Elf32_Ehdr Ehdr;
  31 typedef Elf32_Phdr Phdr;
  32 typedef Elf32_Sym Sym;
  33 #define R_TYPE(x) ((x)&255)
  34 #define R_SYM(x) ((x)>>8)
  35 #else
  36 typedef Elf64_Ehdr Ehdr;
  37 typedef Elf64_Phdr Phdr;
  38 typedef Elf64_Sym Sym;
  39 #define R_TYPE(x) ((x)&0xffffffff)
  40 #define R_SYM(x) ((x)>>32)
  41 #endif
  42
  43 #define MAXP2(a,b) (-(-(a)&-(b)))
  44 #define ALIGN(x,y) ((x)+(y)-1 & -(y))
  45
  46 struct debug {
  47         int ver;
  48         void *head;
  49         void (*bp)(void);
  50         int state;
  51         void *base;
  52 };
  53
  54 struct dso {
  55         unsigned char *base;
  56         char *name;
  57         size_t *dynv;
  58         struct dso *next, *prev;
  59
  60         Phdr *phdr;
  61         int phnum;
  62         int refcnt;
  63         Sym *syms;
  64         uint32_t *hashtab;
  65         uint32_t *ghashtab;
  66         int16_t *versym;
  67         char *strings;
  68         unsigned char *map;
  69         size_t map_len;
  70         dev_t dev;
  71         ino_t ino;
  72         signed char global;
  73         char relocated;
  74         char constructed;
  75         struct dso **deps;
  76         void *tls_image;
  77         size_t tls_len, tls_size, tls_align, tls_id, tls_offset;
  78         void **new_dtv;
  79         unsigned char *new_tls;
  80         int new_dtv_idx, new_tls_idx;
  81         struct dso *fini_next;
  82         char *shortname;
  83         char buf[];
  84 };
  85
  86 struct symdef {
  87         Sym *sym;
  88         struct dso *dso;
  89 };
  90
  91 #include "reloc.h"
  92
  93 void __init_ssp(size_t *);
  94 void *__install_initial_tls(void *);
  95 void __init_libc(char **, char *);
  96
  97 static struct dso *head, *tail, *ldso, *fini_head;
  98 static char *env_path, *sys_path, *r_path;
  99 static unsigned long long gencnt;
 100 static int ssp_used;
 101 static int runtime;
 102 static int ldd_mode;
 103 static int ldso_fail;
 104 static int noload;
 105 static jmp_buf *rtld_fail;
 106 static pthread_rwlock_t lock;
 107 static struct debug debug;
 108 static size_t tls_cnt, tls_offset, tls_align = 4*sizeof(size_t);
 109 static pthread_mutex_t init_fini_lock = { ._m_type = PTHREAD_MUTEX_RECURSIVE };
 110
 111 struct debug *_dl_debug_addr = &debug;
 112
 113 #define AUX_CNT 38
 114 #define DYN_CNT 34
 115
 116 static void decode_vec(size_t *v, size_t *a, size_t cnt)
 117 {
 118         memset(a, 0, cnt*sizeof(size_t));
 119         for (; v[0]; v+=2) if (v[0]<cnt) {
 120                 a[0] |= 1ULL<<v[0];
 121                 a[v[0]] = v[1];
 122         }
 123 }
 124
 125 static int search_vec(size_t *v, size_t *r, size_t key)
 126 {
 127         for (; v[0]!=key; v+=2)
 128                 if (!v[0]) return 0;
 129         *r = v[1];
 130         return 1;
 131 }
 132
 133 static uint32_t sysv_hash(const char *s0)
 134 {
 135         const unsigned char *s = (void *)s0;
 136         uint_fast32_t h = 0;
 137         while (*s) {
 138                 h = 16*h + *s++;
 139                 h ^= h>>24 & 0xf0;
 140         }
 141         return h & 0xfffffff;
 142 }
 143
 144 static uint32_t gnu_hash(const char *s0)
 145 {
 146         const unsigned char *s = (void *)s0;
 147         uint_fast32_t h = 5381;
 148         for (; *s; s++)
 149                 h = h*33 + *s;
 150         return h;
 151 }
 152
 153 static Sym *sysv_lookup(const char *s, uint32_t h, struct dso *dso)
 154 {
 155         size_t i;
 156         Sym *syms = dso->syms;
 157         uint32_t *hashtab = dso->hashtab;
 158         char *strings = dso->strings;
 159         for (i=hashtab[2+h%hashtab[0]]; i; i=hashtab[2+hashtab[0]+i]) {
 160                 if ((!dso->versym || dso->versym[i] >= 0)
 161                     && (!strcmp(s, strings+syms[i].st_name)))
 162                         return syms+i;
 163         }
 164         return 0;
 165 }
 166
 167 static Sym *gnu_lookup(const char *s, uint32_t h1, struct dso *dso)
 168 {
 169         Sym *syms = dso->syms;
 170         char *strings = dso->strings;
 171         uint32_t *hashtab = dso->ghashtab;
 172         uint32_t nbuckets = hashtab[0];
 173         uint32_t *buckets = hashtab + 4 + hashtab[2]*(sizeof(size_t)/4);
 174         uint32_t h2;
 175         uint32_t *hashval;
 176         uint32_t i = buckets[h1 % nbuckets];
 177
 178         if (!i) return 0;
 179
 180         hashval = buckets + nbuckets + (i - hashtab[1]);
 181
 182         for (h1 |= 1; ; i++) {
 183                 h2 = *hashval++;
 184                 if ((!dso->versym || dso->versym[i] >= 0)
 185                     && (h1 == (h2|1)) && !strcmp(s, strings + syms[i].st_name))
 186                         return syms+i;
 187                 if (h2 & 1) break;
 188         }
 189
 190         return 0;
 191 }
 192
 193 #define OK_TYPES (1<<STT_NOTYPE | 1<<STT_OBJECT | 1<<STT_FUNC | 1<<STT_COMMON | 1<<STT_TLS)
 194 #define OK_BINDS (1<<STB_GLOBAL | 1<<STB_WEAK | 1<<STB_GNU_UNIQUE)
 195
 196 static struct symdef find_sym(struct dso *dso, const char *s, int need_def)
 197 {
 198         uint32_t h = 0, gh = 0;
 199         struct symdef def = {0};
 200         if (dso->ghashtab) {
 201                 gh = gnu_hash(s);
 202                 if (gh == 0x1f4039c9 && !strcmp(s, "__stack_chk_fail")) ssp_used = 1;
 203         } else {
 204                 h = sysv_hash(s);
 205                 if (h == 0x595a4cc && !strcmp(s, "__stack_chk_fail")) ssp_used = 1;
 206         }
 207         for (; dso; dso=dso->next) {
 208                 Sym *sym;
 209                 if (!dso->global) continue;
 210                 if (dso->ghashtab) {
 211                         if (!gh) gh = gnu_hash(s);
 212                         sym = gnu_lookup(s, gh, dso);
 213                 } else {
 214                         if (!h) h = sysv_hash(s);
 215                         sym = sysv_lookup(s, h, dso);
 216                 }
 217                 if (!sym) continue;
 218                 if (!sym->st_shndx)
 219                         if (need_def || (sym->st_info&0xf) == STT_TLS)
 220                                 continue;
 221                 if (!sym->st_value)
 222                         if ((sym->st_info&0xf) != STT_TLS)
 223                                 continue;
 224                 if (!(1<<(sym->st_info&0xf) & OK_TYPES)) continue;
 225                 if (!(1<<(sym->st_info>>4) & OK_BINDS)) continue;
 226
 227                 if (def.sym && sym->st_info>>4 == STB_WEAK) continue;
 228                 def.sym = sym;
 229                 def.dso = dso;
 230                 if (sym->st_info>>4 == STB_GLOBAL) break;
 231         }
 232         return def;
 233 }
 234
 235 static void do_relocs(struct dso *dso, size_t *rel, size_t rel_size, size_t stride)
 236 {
 237         unsigned char *base = dso->base;
 238         Sym *syms = dso->syms;
 239         char *strings = dso->strings;
 240         Sym *sym;
 241         const char *name;
 242         void *ctx;
 243         int type;
 244         int sym_index;
 245         struct symdef def;
 246
 247         for (; rel_size; rel+=stride, rel_size-=stride*sizeof(size_t)) {
 248                 type = R_TYPE(rel[1]);
 249                 sym_index = R_SYM(rel[1]);
 250                 if (sym_index) {
 251                         sym = syms + sym_index;
 252                         name = strings + sym->st_name;
 253                         ctx = IS_COPY(type) ? head->next : head;
 254                         def = find_sym(ctx, name, IS_PLT(type));
 255                         if (!def.sym && sym->st_info>>4 != STB_WEAK) {
 256                                 snprintf(errbuf, sizeof errbuf,
 257                                         "Error relocating %s: %s: symbol not found",
 258                                         dso->name, name);
 259                                 if (runtime) longjmp(*rtld_fail, 1);
 260                                 dprintf(2, "%s\n", errbuf);
 261                                 ldso_fail = 1;
 262                                 continue;
 263                         }
 264                 } else {
 265                         sym = 0;
 266                         def.sym = 0;
 267                         def.dso = 0;
 268                 }
 269                 do_single_reloc(dso, base, (void *)(base + rel[0]), type,
 270                         stride>2 ? rel[2] : 0, sym, sym?sym->st_size:0, def,
 271                         def.sym?(size_t)(def.dso->base+def.sym->st_value):0);
 272         }
 273 }
 274
 275 /* A huge hack: to make up for the wastefulness of shared libraries
 276  * needing at least a page of dirty memory even if they have no global
 277  * data, we reclaim the gaps at the beginning and end of writable maps
 278  * and "donate" them to the heap by setting up minimal malloc
 279  * structures and then freeing them. */
 280
 281 static void reclaim(unsigned char *base, size_t start, size_t end)
 282 {
 283         size_t *a, *z;
 284         start = start + 6*sizeof(size_t)-1 & -4*sizeof(size_t);
 285         end = (end & -4*sizeof(size_t)) - 2*sizeof(size_t);
 286         if (start>end || end-start < 4*sizeof(size_t)) return;
 287         a = (size_t *)(base + start);
 288         z = (size_t *)(base + end);
 289         a[-2] = 1;
 290         a[-1] = z[0] = end-start + 2*sizeof(size_t) | 1;
 291         z[1] = 1;
 292         free(a);
 293 }
 294
 295 static void reclaim_gaps(unsigned char *base, Phdr *ph, size_t phent, size_t phcnt)
 296 {
 297         for (; phcnt--; ph=(void *)((char *)ph+phent)) {
 298                 if (ph->p_type!=PT_LOAD) continue;
 299                 if ((ph->p_flags&(PF_R|PF_W))!=(PF_R|PF_W)) continue;
 300                 reclaim(base, ph->p_vaddr & -PAGE_SIZE, ph->p_vaddr);
 301                 reclaim(base, ph->p_vaddr+ph->p_memsz,
 302                         ph->p_vaddr+ph->p_memsz+PAGE_SIZE-1 & -PAGE_SIZE);
 303         }
 304 }
 305
 306 static void *map_library(int fd, struct dso *dso)
 307 {
 308         Ehdr buf[(896+sizeof(Ehdr))/sizeof(Ehdr)];
 309         void *allocated_buf=0;
 310         size_t phsize;
 311         size_t addr_min=SIZE_MAX, addr_max=0, map_len;
 312         size_t this_min, this_max;
 313         off_t off_start;
 314         Ehdr *eh;
 315         Phdr *ph, *ph0;
 316         unsigned prot;
 317         unsigned char *map=MAP_FAILED, *base;
 318         size_t dyn=0;
 319         size_t tls_image=0;
 320         size_t i;
 321
 322         ssize_t l = read(fd, buf, sizeof buf);
 323         eh = buf;
 324         if (l<0) return 0;
 325         if (l<sizeof *eh || (eh->e_type != ET_DYN && eh->e_type != ET_EXEC))
 326                 goto noexec;
 327         phsize = eh->e_phentsize * eh->e_phnum;
 328         if (phsize > sizeof buf - sizeof *eh) {
 329                 allocated_buf = malloc(phsize);
 330                 if (!allocated_buf) return 0;
 331                 l = pread(fd, allocated_buf, phsize, eh->e_phoff);
 332                 if (l < 0) goto error;
 333                 if (l != phsize) goto noexec;
 334                 ph = ph0 = allocated_buf;
 335         } else if (eh->e_phoff + phsize > l) {
 336                 l = pread(fd, buf+1, phsize, eh->e_phoff);
 337                 if (l < 0) goto error;
 338                 if (l != phsize) goto noexec;
 339                 ph = ph0 = (void *)(buf + 1);
 340         } else {
 341                 ph = ph0 = (void *)((char *)buf + eh->e_phoff);
 342         }
 343         for (i=eh->e_phnum; i; i--, ph=(void *)((char *)ph+eh->e_phentsize)) {
 344                 if (ph->p_type == PT_DYNAMIC)
 345                         dyn = ph->p_vaddr;
 346                 if (ph->p_type == PT_TLS) {
 347                         tls_image = ph->p_vaddr;
 348                         dso->tls_align = ph->p_align;
 349                         dso->tls_len = ph->p_filesz;
 350                         dso->tls_size = ph->p_memsz;
 351                 }
 352                 if (ph->p_type != PT_LOAD) continue;
 353                 if (ph->p_vaddr < addr_min) {
 354                         addr_min = ph->p_vaddr;
 355                         off_start = ph->p_offset;
 356                         prot = (((ph->p_flags&PF_R) ? PROT_READ : 0) |
 357                                 ((ph->p_flags&PF_W) ? PROT_WRITE: 0) |
 358                                 ((ph->p_flags&PF_X) ? PROT_EXEC : 0));
 359                 }
 360                 if (ph->p_vaddr+ph->p_memsz > addr_max) {
 361                         addr_max = ph->p_vaddr+ph->p_memsz;
 362                 }
 363         }
 364         if (!dyn) goto noexec;
 365         addr_max += PAGE_SIZE-1;
 366         addr_max &= -PAGE_SIZE;
 367         addr_min &= -PAGE_SIZE;
 368         off_start &= -PAGE_SIZE;
 369         map_len = addr_max - addr_min + off_start;
 370         /* The first time, we map too much, possibly even more than
 371          * the length of the file. This is okay because we will not
 372          * use the invalid part; we just need to reserve the right
 373          * amount of virtual address space to map over later. */
 374         map = mmap((void *)addr_min, map_len, prot, MAP_PRIVATE, fd, off_start);
 375         if (map==MAP_FAILED) goto error;
 376         /* If the loaded file is not relocatable and the requested address is
 377          * not available, then the load operation must fail. */
 378         if (eh->e_type != ET_DYN && addr_min && map!=(void *)addr_min) {
 379                 errno = EBUSY;
 380                 goto error;
 381         }
 382         base = map - addr_min;
 383         dso->phdr = 0;
 384         dso->phnum = 0;
 385         for (ph=ph0, i=eh->e_phnum; i; i--, ph=(void *)((char *)ph+eh->e_phentsize)) {
 386                 if (ph->p_type != PT_LOAD) continue;
 387                 /* Check if the programs headers are in this load segment, and
 388                  * if so, record the address for use by dl_iterate_phdr. */
 389                 if (!dso->phdr && eh->e_phoff >= ph->p_offset
 390                     && eh->e_phoff+phsize <= ph->p_offset+ph->p_filesz) {
 391                         dso->phdr = (void *)(base + ph->p_vaddr
 392                                 + (eh->e_phoff-ph->p_offset));
 393                         dso->phnum = eh->e_phnum;
 394                 }
 395                 /* Reuse the existing mapping for the lowest-address LOAD */
 396                 if ((ph->p_vaddr & -PAGE_SIZE) == addr_min) continue;
 397                 this_min = ph->p_vaddr & -PAGE_SIZE;
 398                 this_max = ph->p_vaddr+ph->p_memsz+PAGE_SIZE-1 & -PAGE_SIZE;
 399                 off_start = ph->p_offset & -PAGE_SIZE;
 400                 prot = (((ph->p_flags&PF_R) ? PROT_READ : 0) |
 401                         ((ph->p_flags&PF_W) ? PROT_WRITE: 0) |
 402                         ((ph->p_flags&PF_X) ? PROT_EXEC : 0));
 403                 if (mmap(base+this_min, this_max-this_min, prot, MAP_PRIVATE|MAP_FIXED, fd, off_start) == MAP_FAILED)
 404                         goto error;
 405                 if (ph->p_memsz > ph->p_filesz) {
 406                         size_t brk = (size_t)base+ph->p_vaddr+ph->p_filesz;
 407                         size_t pgbrk = brk+PAGE_SIZE-1 & -PAGE_SIZE;
 408                         memset((void *)brk, 0, pgbrk-brk & PAGE_SIZE-1);
 409                         if (pgbrk-(size_t)base < this_max && mmap((void *)pgbrk, (size_t)base+this_max-pgbrk, prot, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) == MAP_FAILED)
 410                                 goto error;
 411                 }
 412         }
 413         for (i=0; ((size_t *)(base+dyn))[i]; i+=2)
 414                 if (((size_t *)(base+dyn))[i]==DT_TEXTREL) {
 415                         if (mprotect(map, map_len, PROT_READ|PROT_WRITE|PROT_EXEC) < 0)
 416                                 goto error;
 417                         break;
 418                 }
 419         if (!runtime) reclaim_gaps(base, ph0, eh->e_phentsize, eh->e_phnum);
 420         dso->map = map;
 421         dso->map_len = map_len;
 422         dso->base = base;
 423         dso->dynv = (void *)(base+dyn);
 424         if (dso->tls_size) dso->tls_image = (void *)(base+tls_image);
 425         free(allocated_buf);
 426         return map;
 427 noexec:
 428         errno = ENOEXEC;
 429 error:
 430         if (map!=MAP_FAILED) munmap(map, map_len);
 431         free(allocated_buf);
 432         return 0;
 433 }
 434
 435 static int path_open(const char *name, const char *s, char *buf, size_t buf_size)
 436 {
 437         size_t l;
 438         int fd;
 439         for (;;) {
 440                 s += strspn(s, ":\n");
 441                 l = strcspn(s, ":\n");
 442                 if (l-1 >= INT_MAX) return -1;
 443                 if (snprintf(buf, buf_size, "%.*s/%s", (int)l, s, name) >= buf_size)
 444                         continue;
 445                 if ((fd = open(buf, O_RDONLY|O_CLOEXEC))>=0) return fd;
 446                 s += l;
 447         }
 448 }
 449
 450 static void decode_dyn(struct dso *p)
 451 {
 452         size_t dyn[DYN_CNT] = {0};
 453         decode_vec(p->dynv, dyn, DYN_CNT);
 454         p->syms = (void *)(p->base + dyn[DT_SYMTAB]);
 455         p->strings = (void *)(p->base + dyn[DT_STRTAB]);
 456         if (dyn[0]&(1<<DT_HASH))
 457                 p->hashtab = (void *)(p->base + dyn[DT_HASH]);
 458         if (search_vec(p->dynv, dyn, DT_GNU_HASH))
 459                 p->ghashtab = (void *)(p->base + *dyn);
 460         if (search_vec(p->dynv, dyn, DT_VERSYM))
 461                 p->versym = (void *)(p->base + *dyn);
 462 }
 463
 464 static struct dso *load_library(const char *name)
 465 {
 466         char buf[2*NAME_MAX+2];
 467         const char *pathname;
 468         unsigned char *map;
 469         struct dso *p, temp_dso = {0};
 470         int fd;
 471         struct stat st;
 472         size_t alloc_size;
 473         int n_th = 0;
 474         int is_self = 0;
 475
 476         /* Catch and block attempts to reload the implementation itself */
 477         if (name[0]=='l' && name[1]=='i' && name[2]=='b') {
 478                 static const char *rp, reserved[] =
 479                         "c\0pthread\0rt\0m\0dl\0util\0xnet\0";
 480                 char *z = strchr(name, '.');
 481                 if (z) {
 482                         size_t l = z-name;
 483                         for (rp=reserved; *rp && strncmp(name+3, rp, l-3); rp+=strlen(rp)+1);
 484                         if (*rp) {
 485                                 if (ldd_mode) {
 486                                         /* Track which names have been resolved
 487                                          * and only report each one once. */
 488                                         static unsigned reported;
 489                                         unsigned mask = 1U<<(rp-reserved);
 490                                         if (!(reported & mask)) {
 491                                                 reported |= mask;
 492                                                 dprintf(1, "\t%s => %s (%p)\n",
 493                                                         name, ldso->name,
 494                                                         ldso->base);
 495                                         }
 496                                 }
 497                                 is_self = 1;
 498                         }
 499                 }
 500         }
 501         if (!strcmp(name, ldso->name)) is_self = 1;
 502         if (is_self) {
 503                 if (!ldso->prev) {
 504                         tail->next = ldso;
 505                         ldso->prev = tail;
 506                         tail = ldso->next ? ldso->next : ldso;
 507                 }
 508                 return ldso;
 509         }
 510         if (strchr(name, '/')) {
 511                 pathname = name;
 512                 fd = open(name, O_RDONLY|O_CLOEXEC);
 513         } else {
 514                 /* Search for the name to see if it's already loaded */
 515                 for (p=head->next; p; p=p->next) {
 516                         if (p->shortname && !strcmp(p->shortname, name)) {
 517                                 p->refcnt++;
 518                                 return p;
 519                         }
 520                 }
 521                 if (strlen(name) > NAME_MAX) return 0;
 522                 fd = -1;
 523                 if (env_path) fd = path_open(name, env_path, buf, sizeof buf);
 524                 if (fd < 0 && r_path) fd = path_open(name, r_path, buf, sizeof buf);
 525                 if (fd < 0) {
 526                         if (!sys_path) {
 527                                 char *prefix = 0;
 528                                 size_t prefix_len;
 529                                 if (ldso->name[0]=='/') {
 530                                         char *s, *t, *z;
 531                                         for (s=t=z=ldso->name; *s; s++)
 532                                                 if (*s=='/') z=t, t=s;
 533                                         prefix_len = z-ldso->name;
 534                                         if (prefix_len < PATH_MAX)
 535                                                 prefix = ldso->name;
 536                                 }
 537                                 if (!prefix) {
 538                                         prefix = "";
 539                                         prefix_len = 0;
 540                                 }
 541                                 char etc_ldso_path[prefix_len + 1
 542                                         + sizeof "/etc/ld-musl-" LDSO_ARCH ".path"];
 543                                 snprintf(etc_ldso_path, sizeof etc_ldso_path,
 544                                         "%.*s/etc/ld-musl-" LDSO_ARCH ".path",
 545                                         (int)prefix_len, prefix);
 546                                 FILE *f = fopen(etc_ldso_path, "rbe");
 547                                 if (f) {
 548                                         if (getdelim(&sys_path, (size_t[1]){0}, 0, f) <= 0) {
 549                                                 free(sys_path);
 550                                                 sys_path = "";
 551                                         }
 552                                         fclose(f);
 553                                 }
 554                         }
 555                         if (!sys_path) sys_path = "/lib:/usr/local/lib:/usr/lib";
 556                         fd = path_open(name, sys_path, buf, sizeof buf);
 557                 }
 558                 pathname = buf;
 559         }
 560         if (fd < 0) return 0;
 561         if (fstat(fd, &st) < 0) {
 562                 close(fd);
 563                 return 0;
 564         }
 565         for (p=head->next; p; p=p->next) {
 566                 if (p->dev == st.st_dev && p->ino == st.st_ino) {
 567                         /* If this library was previously loaded with a
 568                          * pathname but a search found the same inode,
 569                          * setup its shortname so it can be found by name. */
 570                         if (!p->shortname && pathname != name)
 571                                 p->shortname = strrchr(p->name, '/')+1;
 572                         close(fd);
 573                         p->refcnt++;
 574                         return p;
 575                 }
 576         }
 577         map = noload ? 0 : map_library(fd, &temp_dso);
 578         close(fd);
 579         if (!map) return 0;
 580
 581         /* Allocate storage for the new DSO. When there is TLS, this
 582          * storage must include a reservation for all pre-existing
 583          * threads to obtain copies of both the new TLS, and an
 584          * extended DTV capable of storing an additional slot for
 585          * the newly-loaded DSO. */
 586         alloc_size = sizeof *p + strlen(pathname) + 1;
 587         if (runtime && temp_dso.tls_image) {
 588                 size_t per_th = temp_dso.tls_size + temp_dso.tls_align
 589                         + sizeof(void *) * (tls_cnt+3);
 590                 n_th = libc.threads_minus_1 + 1;
 591                 if (n_th > SSIZE_MAX / per_th) alloc_size = SIZE_MAX;
 592                 else alloc_size += n_th * per_th;
 593         }
 594         p = calloc(1, alloc_size);
 595         if (!p) {
 596                 munmap(map, temp_dso.map_len);
 597                 return 0;
 598         }
 599         memcpy(p, &temp_dso, sizeof temp_dso);
 600         decode_dyn(p);
 601         p->dev = st.st_dev;
 602         p->ino = st.st_ino;
 603         p->refcnt = 1;
 604         p->name = p->buf;
 605         strcpy(p->name, pathname);
 606         /* Add a shortname only if name arg was not an explicit pathname. */
 607         if (pathname != name) p->shortname = strrchr(p->name, '/')+1;
 608         if (p->tls_image) {
 609                 if (runtime && !__pthread_self_init()) {
 610                         munmap(map, p->map_len);
 611                         free(p);
 612                         return 0;
 613                 }
 614                 p->tls_id = ++tls_cnt;
 615                 tls_align = MAXP2(tls_align, p->tls_align);
 616 #ifdef TLS_ABOVE_TP
 617                 p->tls_offset = tls_offset + ( (tls_align-1) &
 618                         -(tls_offset + (uintptr_t)p->tls_image) );
 619                 tls_offset += p->tls_size;
 620 #else
 621                 tls_offset += p->tls_size + p->tls_align - 1;
 622                 tls_offset -= (tls_offset + (uintptr_t)p->tls_image)
 623                         & (p->tls_align-1);
 624                 p->tls_offset = tls_offset;
 625 #endif
 626                 p->new_dtv = (void *)(-sizeof(size_t) &
 627                         (uintptr_t)(p->name+strlen(p->name)+sizeof(size_t)));
 628                 p->new_tls = (void *)(p->new_dtv + n_th*(tls_cnt+1));
 629         }
 630
 631         tail->next = p;
 632         p->prev = tail;
 633         tail = p;
 634
 635         if (ldd_mode) dprintf(1, "\t%s => %s (%p)\n", name, pathname, p->base);
 636
 637         return p;
 638 }
 639
 640 static void load_deps(struct dso *p)
 641 {
 642         size_t i, ndeps=0;
 643         struct dso ***deps = &p->deps, **tmp, *dep;
 644         for (; p; p=p->next) {
 645                 for (i=0; p->dynv[i]; i+=2) {
 646                         if (p->dynv[i] != DT_RPATH) continue;
 647                         r_path = (void *)(p->strings + p->dynv[i+1]);
 648                 }
 649                 for (i=0; p->dynv[i]; i+=2) {
 650                         if (p->dynv[i] != DT_NEEDED) continue;
 651                         dep = load_library(p->strings + p->dynv[i+1]);
 652                         if (!dep) {
 653                                 snprintf(errbuf, sizeof errbuf,
 654                                         "Error loading shared library %s: %m (needed by %s)",
 655                                         p->strings + p->dynv[i+1], p->name);
 656                                 if (runtime) longjmp(*rtld_fail, 1);
 657                                 dprintf(2, "%s\n", errbuf);
 658                                 ldso_fail = 1;
 659                                 continue;
 660                         }
 661                         if (runtime) {
 662                                 tmp = realloc(*deps, sizeof(*tmp)*(ndeps+2));
 663                                 if (!tmp) longjmp(*rtld_fail, 1);
 664                                 tmp[ndeps++] = dep;
 665                                 tmp[ndeps] = 0;
 666                                 *deps = tmp;
 667                         }
 668                 }
 669                 r_path = 0;
 670         }
 671 }
 672
 673 static void load_preload(char *s)
 674 {
 675         int tmp;
 676         char *z;
 677         for (z=s; *z; s=z) {
 678                 for (   ; *s && isspace(*s); s++);
 679                 for (z=s; *z && !isspace(*z); z++);
 680                 tmp = *z;
 681                 *z = 0;
 682                 load_library(s);
 683                 *z = tmp;
 684         }
 685 }
 686
 687 static void make_global(struct dso *p)
 688 {
 689         for (; p; p=p->next) p->global = 1;
 690 }
 691
 692 static void reloc_all(struct dso *p)
 693 {
 694         size_t dyn[DYN_CNT] = {0};
 695         for (; p; p=p->next) {
 696                 if (p->relocated) continue;
 697                 decode_vec(p->dynv, dyn, DYN_CNT);
 698 #ifdef NEED_ARCH_RELOCS
 699                 do_arch_relocs(p, head);
 700 #endif
 701                 do_relocs(p, (void *)(p->base+dyn[DT_JMPREL]), dyn[DT_PLTRELSZ],
 702                         2+(dyn[DT_PLTREL]==DT_RELA));
 703                 do_relocs(p, (void *)(p->base+dyn[DT_REL]), dyn[DT_RELSZ], 2);
 704                 do_relocs(p, (void *)(p->base+dyn[DT_RELA]), dyn[DT_RELASZ], 3);
 705                 p->relocated = 1;
 706         }
 707 }
 708
 709 static size_t find_dyn(Phdr *ph, size_t cnt, size_t stride)
 710 {
 711         for (; cnt--; ph = (void *)((char *)ph + stride))
 712                 if (ph->p_type == PT_DYNAMIC)
 713                         return ph->p_vaddr;
 714         return 0;
 715 }
 716
 717 static void find_map_range(Phdr *ph, size_t cnt, size_t stride, struct dso *p)
 718 {
 719         size_t min_addr = -1, max_addr = 0;
 720         for (; cnt--; ph = (void *)((char *)ph + stride)) {
 721                 if (ph->p_type != PT_LOAD) continue;
 722                 if (ph->p_vaddr < min_addr)
 723                         min_addr = ph->p_vaddr;
 724                 if (ph->p_vaddr+ph->p_memsz > max_addr)
 725                         max_addr = ph->p_vaddr+ph->p_memsz;
 726         }
 727         min_addr &= -PAGE_SIZE;
 728         max_addr = (max_addr + PAGE_SIZE-1) & -PAGE_SIZE;
 729         p->map = p->base + min_addr;
 730         p->map_len = max_addr - min_addr;
 731 }
 732
 733 static void do_fini()
 734 {
 735         struct dso *p;
 736         size_t dyn[DYN_CNT] = {0};
 737         for (p=fini_head; p; p=p->fini_next) {
 738                 if (!p->constructed) continue;
 739                 decode_vec(p->dynv, dyn, DYN_CNT);
 740                 if (dyn[0] & (1<<DT_FINI_ARRAY)) {
 741                         size_t n = dyn[DT_FINI_ARRAYSZ]/sizeof(size_t);
 742                         size_t *fn = (size_t *)(p->base + dyn[DT_FINI_ARRAY])+n;
 743                         while (n--) ((void (*)(void))*--fn)();
 744                 }
 745 #ifndef NO_LEGACY_INITFINI
 746                 if ((dyn[0] & (1<<DT_FINI)) && dyn[DT_FINI])
 747                         ((void (*)(void))(p->base + dyn[DT_FINI]))();
 748 #endif
 749         }
 750 }
 751
 752 static void do_init_fini(struct dso *p)
 753 {
 754         size_t dyn[DYN_CNT] = {0};
 755         int need_locking = libc.threads_minus_1;
 756         /* Allow recursive calls that arise when a library calls
 757          * dlopen from one of its constructors, but block any
 758          * other threads until all ctors have finished. */
 759         if (need_locking) pthread_mutex_lock(&init_fini_lock);
 760         for (; p; p=p->prev) {
 761                 if (p->constructed) continue;
 762                 p->constructed = 1;
 763                 decode_vec(p->dynv, dyn, DYN_CNT);
 764                 if (dyn[0] & ((1<<DT_FINI) | (1<<DT_FINI_ARRAY))) {
 765                         p->fini_next = fini_head;
 766                         fini_head = p;
 767                 }
 768 #ifndef NO_LEGACY_INITFINI
 769                 if ((dyn[0] & (1<<DT_INIT)) && dyn[DT_INIT])
 770                         ((void (*)(void))(p->base + dyn[DT_INIT]))();
 771 #endif
 772                 if (dyn[0] & (1<<DT_INIT_ARRAY)) {
 773                         size_t n = dyn[DT_INIT_ARRAYSZ]/sizeof(size_t);
 774                         size_t *fn = (void *)(p->base + dyn[DT_INIT_ARRAY]);
 775                         while (n--) ((void (*)(void))*fn++)();
 776                 }
 777                 if (!need_locking && libc.threads_minus_1) {
 778                         need_locking = 1;
 779                         pthread_mutex_lock(&init_fini_lock);
 780                 }
 781         }
 782         if (need_locking) pthread_mutex_unlock(&init_fini_lock);
 783 }
 784
 785 void _dl_debug_state(void)
 786 {
 787 }
 788
 789 void __reset_tls()
 790 {
 791         pthread_t self = __pthread_self();
 792         struct dso *p;
 793         for (p=head; p; p=p->next) {
 794                 if (!p->tls_id || !self->dtv[p->tls_id]) continue;
 795                 memcpy(self->dtv[p->tls_id], p->tls_image, p->tls_len);
 796                 memset((char *)self->dtv[p->tls_id]+p->tls_len, 0,
 797                         p->tls_size - p->tls_len);
 798                 if (p->tls_id == (size_t)self->dtv[0]) break;
 799         }
 800 }
 801
 802 void *__copy_tls(unsigned char *mem)
 803 {
 804         pthread_t td;
 805         struct dso *p;
 806
 807         if (!tls_cnt) return mem;
 808
 809         void **dtv = (void *)mem;
 810         dtv[0] = (void *)tls_cnt;
 811
 812 #ifdef TLS_ABOVE_TP
 813         mem += sizeof(void *) * (tls_cnt+1);
 814         mem += -((uintptr_t)mem + sizeof(struct pthread)) & (tls_align-1);
 815         td = (pthread_t)mem;
 816         mem += sizeof(struct pthread);
 817
 818         for (p=head; p; p=p->next) {
 819                 if (!p->tls_id) continue;
 820                 dtv[p->tls_id] = mem + p->tls_offset;
 821                 memcpy(dtv[p->tls_id], p->tls_image, p->tls_len);
 822         }
 823 #else
 824         mem += libc.tls_size - sizeof(struct pthread);
 825         mem -= (uintptr_t)mem & (tls_align-1);
 826         td = (pthread_t)mem;
 827
 828         for (p=head; p; p=p->next) {
 829                 if (!p->tls_id) continue;
 830                 dtv[p->tls_id] = mem - p->tls_offset;
 831                 memcpy(dtv[p->tls_id], p->tls_image, p->tls_len);
 832         }
 833 #endif
 834         td->dtv = dtv;
 835         return td;
 836 }
 837
 838 void *__tls_get_addr(size_t *v)
 839 {
 840         pthread_t self = __pthread_self();
 841         if (v[0]<=(size_t)self->dtv[0] && self->dtv[v[0]])
 842                 return (char *)self->dtv[v[0]]+v[1];
 843
 844         /* Block signals to make accessing new TLS async-signal-safe */
 845         sigset_t set;
 846         pthread_sigmask(SIG_BLOCK, SIGALL_SET, &set);
 847         if (v[0]<=(size_t)self->dtv[0] && self->dtv[v[0]]) {
 848                 pthread_sigmask(SIG_SETMASK, &set, 0);
 849                 return (char *)self->dtv[v[0]]+v[1];
 850         }
 851
 852         /* This is safe without any locks held because, if the caller
 853          * is able to request the Nth entry of the DTV, the DSO list
 854          * must be valid at least that far out and it was synchronized
 855          * at program startup or by an already-completed call to dlopen. */
 856         struct dso *p;
 857         for (p=head; p->tls_id != v[0]; p=p->next);
 858
 859         /* Get new DTV space from new DSO if needed */
 860         if (v[0] > (size_t)self->dtv[0]) {
 861                 void **newdtv = p->new_dtv +
 862                         (v[0]+1)*sizeof(void *)*a_fetch_add(&p->new_dtv_idx,1);
 863                 memcpy(newdtv, self->dtv,
 864                         ((size_t)self->dtv[0]+1) * sizeof(void *));
 865                 newdtv[0] = (void *)v[0];
 866                 self->dtv = newdtv;
 867         }
 868
 869         /* Get new TLS memory from new DSO */
 870         unsigned char *mem = p->new_tls +
 871                 (p->tls_size + p->tls_align) * a_fetch_add(&p->new_tls_idx,1);
 872         mem += ((uintptr_t)p->tls_image - (uintptr_t)mem) & (p->tls_align-1);
 873         self->dtv[v[0]] = mem;
 874         memcpy(mem, p->tls_image, p->tls_len);
 875         pthread_sigmask(SIG_SETMASK, &set, 0);
 876         return mem + v[1];
 877 }
 878
 879 static void update_tls_size()
 880 {
 881         libc.tls_size = ALIGN(
 882                 (1+tls_cnt) * sizeof(void *) +
 883                 tls_offset +
 884                 sizeof(struct pthread) +
 885                 tls_align * 2,
 886         tls_align);
 887 }
 888
 889 void *__dynlink(int argc, char **argv)
 890 {
 891         size_t aux[AUX_CNT] = {0};
 892         size_t i;
 893         Phdr *phdr;
 894         Ehdr *ehdr;
 895         static struct dso builtin_dsos[3];
 896         struct dso *const app = builtin_dsos+0;
 897         struct dso *const lib = builtin_dsos+1;
 898         struct dso *const vdso = builtin_dsos+2;
 899         char *env_preload=0;
 900         size_t vdso_base;
 901         size_t *auxv;
 902         char **envp = argv+argc+1;
 903
 904         /* Find aux vector just past environ[] */
 905         for (i=argc+1; argv[i]; i++)
 906                 if (!memcmp(argv[i], "LD_LIBRARY_PATH=", 16))
 907                         env_path = argv[i]+16;
 908                 else if (!memcmp(argv[i], "LD_PRELOAD=", 11))
 909                         env_preload = argv[i]+11;
 910         auxv = (void *)(argv+i+1);
 911
 912         decode_vec(auxv, aux, AUX_CNT);
 913
 914         /* Only trust user/env if kernel says we're not suid/sgid */
 915         if ((aux[0]&0x7800)!=0x7800 || aux[AT_UID]!=aux[AT_EUID]
 916           || aux[AT_GID]!=aux[AT_EGID] || aux[AT_SECURE]) {
 917                 env_path = 0;
 918                 env_preload = 0;
 919         }
 920
 921         /* If the dynamic linker was invoked as a program itself, AT_BASE
 922          * will not be set. In that case, we assume the base address is
 923          * the start of the page containing the PHDRs; I don't know any
 924          * better approach... */
 925         if (!aux[AT_BASE]) {
 926                 aux[AT_BASE] = aux[AT_PHDR] & -PAGE_SIZE;
 927                 aux[AT_PHDR] = aux[AT_PHENT] = aux[AT_PHNUM] = 0;
 928         }
 929
 930         /* The dynamic linker load address is passed by the kernel
 931          * in the AUX vector, so this is easy. */
 932         lib->base = (void *)aux[AT_BASE];
 933         lib->name = lib->shortname = "libc.so";
 934         lib->global = 1;
 935         ehdr = (void *)lib->base;
 936         lib->phnum = ehdr->e_phnum;
 937         lib->phdr = (void *)(aux[AT_BASE]+ehdr->e_phoff);
 938         find_map_range(lib->phdr, ehdr->e_phnum, ehdr->e_phentsize, lib);
 939         lib->dynv = (void *)(lib->base + find_dyn(lib->phdr,
 940                 ehdr->e_phnum, ehdr->e_phentsize));
 941         decode_dyn(lib);
 942
 943         if (aux[AT_PHDR]) {
 944                 size_t interp_off = 0;
 945                 size_t tls_image = 0;
 946                 /* Find load address of the main program, via AT_PHDR vs PT_PHDR. */
 947                 app->phdr = phdr = (void *)aux[AT_PHDR];
 948                 app->phnum = aux[AT_PHNUM];
 949                 for (i=aux[AT_PHNUM]; i; i--, phdr=(void *)((char *)phdr + aux[AT_PHENT])) {
 950                         if (phdr->p_type == PT_PHDR)
 951                                 app->base = (void *)(aux[AT_PHDR] - phdr->p_vaddr);
 952                         else if (phdr->p_type == PT_INTERP)
 953                                 interp_off = (size_t)phdr->p_vaddr;
 954                         else if (phdr->p_type == PT_TLS) {
 955                                 tls_image = phdr->p_vaddr;
 956                                 app->tls_len = phdr->p_filesz;
 957                                 app->tls_size = phdr->p_memsz;
 958                                 app->tls_align = phdr->p_align;
 959                         }
 960                 }
 961                 if (app->tls_size) app->tls_image = (char *)app->base + tls_image;
 962                 if (interp_off) lib->name = (char *)app->base + interp_off;
 963                 app->name = argv[0];
 964                 app->dynv = (void *)(app->base + find_dyn(
 965                         (void *)aux[AT_PHDR], aux[AT_PHNUM], aux[AT_PHENT]));
 966                 find_map_range((void *)aux[AT_PHDR],
 967                         aux[AT_PHNUM], aux[AT_PHENT], app);
 968         } else {
 969                 int fd;
 970                 char *ldname = argv[0];
 971                 size_t l = strlen(ldname);
 972                 if (l >= 3 && !strcmp(ldname+l-3, "ldd")) ldd_mode = 1;
 973                 *argv++ = (void *)-1;
 974                 if (argv[0] && !strcmp(argv[0], "--")) *argv++ = (void *)-1;
 975                 if (!argv[0]) {
 976                         dprintf(2, "musl libc/dynamic program loader\n");
 977                         dprintf(2, "usage: %s pathname%s\n", ldname,
 978                                 ldd_mode ? "" : " [args]");
 979                         _exit(1);
 980                 }
 981                 fd = open(argv[0], O_RDONLY);
 982                 if (fd < 0) {
 983                         dprintf(2, "%s: cannot load %s: %s\n", ldname, argv[0], strerror(errno));
 984                         _exit(1);
 985                 }
 986                 runtime = 1;
 987                 ehdr = (void *)map_library(fd, app);
 988                 if (!ehdr) {
 989                         dprintf(2, "%s: %s: Not a valid dynamic program\n", ldname, argv[0]);
 990                         _exit(1);
 991                 }
 992                 runtime = 0;
 993                 close(fd);
 994                 lib->name = ldname;
 995                 app->name = argv[0];
 996                 aux[AT_ENTRY] = (size_t)app->base + ehdr->e_entry;
 997                 /* Find the name that would have been used for the dynamic
 998                  * linker had ldd not taken its place. */
 999                 if (ldd_mode) {
1000                         for (i=0; i<app->phnum; i++) {
1001                                 if (app->phdr[i].p_type == PT_INTERP)
1002                                         lib->name = (void *)(app->base
1003                                                 + app->phdr[i].p_vaddr);
1004                         }
1005                         dprintf(1, "\t%s (%p)\n", lib->name, lib->base);
1006                 }
1007         }
1008         if (app->tls_size) {
1009                 app->tls_id = tls_cnt = 1;
1010 #ifdef TLS_ABOVE_TP
1011                 app->tls_offset = 0;
1012                 tls_offset = app->tls_size
1013                         + ( -((uintptr_t)app->tls_image + app->tls_size)
1014                         & (app->tls_align-1) );
1015 #else
1016                 tls_offset = app->tls_offset = app->tls_size
1017                         + ( -((uintptr_t)app->tls_image + app->tls_size)
1018                         & (app->tls_align-1) );
1019 #endif
1020                 tls_align = MAXP2(tls_align, app->tls_align);
1021         }
1022         app->global = 1;
1023         decode_dyn(app);
1024
1025         /* Attach to vdso, if provided by the kernel */
1026         if (search_vec(auxv, &vdso_base, AT_SYSINFO_EHDR)) {
1027                 ehdr = (void *)vdso_base;
1028                 vdso->phdr = phdr = (void *)(vdso_base + ehdr->e_phoff);
1029                 vdso->phnum = ehdr->e_phnum;
1030                 for (i=ehdr->e_phnum; i; i--, phdr=(void *)((char *)phdr + ehdr->e_phentsize)) {
1031                         if (phdr->p_type == PT_DYNAMIC)
1032                                 vdso->dynv = (void *)(vdso_base + phdr->p_offset);
1033                         if (phdr->p_type == PT_LOAD)
1034                                 vdso->base = (void *)(vdso_base - phdr->p_vaddr + phdr->p_offset);
1035                 }
1036                 vdso->name = "";
1037                 vdso->shortname = "linux-gate.so.1";
1038                 vdso->global = 1;
1039                 decode_dyn(vdso);
1040                 vdso->prev = lib;
1041                 lib->next = vdso;
1042         }
1043
1044         /* Initial dso chain consists only of the app. We temporarily
1045          * append the dynamic linker/libc so we can relocate it, then
1046          * restore the initial chain in preparation for loading third
1047          * party libraries (preload/needed). */
1048         head = tail = app;
1049         ldso = lib;
1050         app->next = lib;
1051         reloc_all(lib);
1052         app->next = 0;
1053
1054         /* PAST THIS POINT, ALL LIBC INTERFACES ARE FULLY USABLE. */
1055
1056         /* Donate unused parts of app and library mapping to malloc */
1057         reclaim_gaps(app->base, (void *)aux[AT_PHDR], aux[AT_PHENT], aux[AT_PHNUM]);
1058         ehdr = (void *)lib->base;
1059         reclaim_gaps(lib->base, (void *)(lib->base+ehdr->e_phoff),
1060                 ehdr->e_phentsize, ehdr->e_phnum);
1061
1062         /* Load preload/needed libraries, add their symbols to the global
1063          * namespace, and perform all remaining relocations. The main
1064          * program must be relocated LAST since it may contain copy
1065          * relocations which depend on libraries' relocations. */
1066         if (env_preload) load_preload(env_preload);
1067         load_deps(app);
1068         make_global(app);
1069
1070         reloc_all(app->next);
1071         reloc_all(app);
1072
1073         update_tls_size();
1074         if (tls_cnt) {
1075                 void *mem = mmap(0, libc.tls_size, PROT_READ|PROT_WRITE,
1076                         MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
1077                 if (mem==MAP_FAILED ||
1078                     !__install_initial_tls(__copy_tls(mem))) {
1079                         dprintf(2, "%s: Error getting %zu bytes thread-local storage: %m\n",
1080                                 argv[0], libc.tls_size);
1081                         _exit(127);
1082                 }
1083         }
1084
1085         if (ldso_fail) _exit(127);
1086         if (ldd_mode) _exit(0);
1087
1088         /* Switch to runtime mode: any further failures in the dynamic
1089          * linker are a reportable failure rather than a fatal startup
1090          * error. If the dynamic loader (dlopen) will not be used, free
1091          * all memory used by the dynamic linker. */
1092         runtime = 1;
1093
1094 #ifndef DYNAMIC_IS_RO
1095         for (i=0; app->dynv[i]; i+=2)
1096                 if (app->dynv[i]==DT_DEBUG)
1097                         app->dynv[i+1] = (size_t)&debug;
1098 #endif
1099         debug.ver = 1;
1100         debug.bp = _dl_debug_state;
1101         debug.head = head;
1102         debug.base = lib->base;
1103         debug.state = 0;
1104         _dl_debug_state();
1105
1106         if (ssp_used) __init_ssp((void *)aux[AT_RANDOM]);
1107         __init_libc(envp, argv[0]);
1108         atexit(do_fini);
1109         errno = 0;
1110         do_init_fini(tail);
1111
1112         return (void *)aux[AT_ENTRY];
1113 }
1114
1115 void *dlopen(const char *file, int mode)
1116 {
1117         struct dso *volatile p, *orig_tail, *next;
1118         size_t orig_tls_cnt, orig_tls_offset, orig_tls_align;
1119         size_t i;
1120         int cs;
1121         jmp_buf jb;
1122
1123         if (!file) return head;
1124
1125         pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
1126         pthread_rwlock_wrlock(&lock);
1127         __inhibit_ptc();
1128
1129         p = 0;
1130         orig_tls_cnt = tls_cnt;
1131         orig_tls_offset = tls_offset;
1132         orig_tls_align = tls_align;
1133         orig_tail = tail;
1134         noload = mode & RTLD_NOLOAD;
1135
1136         rtld_fail = &jb;
1137         if (setjmp(*rtld_fail)) {
1138                 /* Clean up anything new that was (partially) loaded */
1139                 if (p && p->deps) for (i=0; p->deps[i]; i++)
1140                         if (p->deps[i]->global < 0)
1141                                 p->deps[i]->global = 0;
1142                 for (p=orig_tail->next; p; p=next) {
1143                         next = p->next;
1144                         munmap(p->map, p->map_len);
1145                         free(p->deps);
1146                         free(p);
1147                 }
1148                 tls_cnt = orig_tls_cnt;
1149                 tls_offset = orig_tls_offset;
1150                 tls_align = orig_tls_align;
1151                 tail = orig_tail;
1152                 tail->next = 0;
1153                 p = 0;
1154                 errflag = 1;
1155                 goto end;
1156         } else p = load_library(file);
1157
1158         if (!p) {
1159                 snprintf(errbuf, sizeof errbuf, noload ?
1160                         "Library %s is not already loaded" :
1161                         "Error loading shared library %s: %m",
1162                         file);
1163                 errflag = 1;
1164                 goto end;
1165         }
1166
1167         /* First load handling */
1168         if (!p->deps) {
1169                 load_deps(p);
1170                 if (p->deps) for (i=0; p->deps[i]; i++)
1171                         if (!p->deps[i]->global)
1172                                 p->deps[i]->global = -1;
1173                 if (!p->global) p->global = -1;
1174                 reloc_all(p);
1175                 if (p->deps) for (i=0; p->deps[i]; i++)
1176                         if (p->deps[i]->global < 0)
1177                                 p->deps[i]->global = 0;
1178                 if (p->global < 0) p->global = 0;
1179         }
1180
1181         if (mode & RTLD_GLOBAL) {
1182                 if (p->deps) for (i=0; p->deps[i]; i++)
1183                         p->deps[i]->global = 1;
1184                 p->global = 1;
1185         }
1186
1187         update_tls_size();
1188
1189         if (ssp_used) __init_ssp(libc.auxv);
1190
1191         _dl_debug_state();
1192         orig_tail = tail;
1193 end:
1194         __release_ptc();
1195         if (p) gencnt++;
1196         pthread_rwlock_unlock(&lock);
1197         if (p) do_init_fini(orig_tail);
1198         pthread_setcancelstate(cs, 0);
1199         return p;
1200 }
1201
1202 static int invalid_dso_handle(void *h)
1203 {
1204         struct dso *p;
1205         for (p=head; p; p=p->next) if (h==p) return 0;
1206         snprintf(errbuf, sizeof errbuf, "Invalid library handle %p", (void *)h);
1207         errflag = 1;
1208         return 1;
1209 }
1210
1211 static void *do_dlsym(struct dso *p, const char *s, void *ra)
1212 {
1213         size_t i;
1214         uint32_t h = 0, gh = 0;
1215         Sym *sym;
1216         if (p == head || p == RTLD_DEFAULT || p == RTLD_NEXT) {
1217                 if (p == RTLD_DEFAULT) {
1218                         p = head;
1219                 } else if (p == RTLD_NEXT) {
1220                         for (p=head; p && (unsigned char *)ra-p->map>p->map_len; p=p->next);
1221                         if (!p) p=head;
1222                         p = p->next;
1223                 }
1224                 struct symdef def = find_sym(p, s, 0);
1225                 if (!def.sym) goto failed;
1226                 if ((def.sym->st_info&0xf) == STT_TLS)
1227                         return __tls_get_addr((size_t []){def.dso->tls_id, def.sym->st_value});
1228                 return def.dso->base + def.sym->st_value;
1229         }
1230         if (p != RTLD_DEFAULT && p != RTLD_NEXT && invalid_dso_handle(p))
1231                 return 0;
1232         if (p->ghashtab) {
1233                 gh = gnu_hash(s);
1234                 sym = gnu_lookup(s, gh, p);
1235         } else {
1236                 h = sysv_hash(s);
1237                 sym = sysv_lookup(s, h, p);
1238         }
1239         if (sym && (sym->st_info&0xf) == STT_TLS)
1240                 return __tls_get_addr((size_t []){p->tls_id, sym->st_value});
1241         if (sym && sym->st_value && (1<<(sym->st_info&0xf) & OK_TYPES))
1242                 return p->base + sym->st_value;
1243         if (p->deps) for (i=0; p->deps[i]; i++) {
1244                 if (p->deps[i]->ghashtab) {
1245                         if (!gh) gh = gnu_hash(s);
1246                         sym = gnu_lookup(s, gh, p->deps[i]);
1247                 } else {
1248                         if (!h) h = sysv_hash(s);
1249                         sym = sysv_lookup(s, h, p->deps[i]);
1250                 }
1251                 if (sym && (sym->st_info&0xf) == STT_TLS)
1252                         return __tls_get_addr((size_t []){p->deps[i]->tls_id, sym->st_value});
1253                 if (sym && sym->st_value && (1<<(sym->st_info&0xf) & OK_TYPES))
1254                         return p->deps[i]->base + sym->st_value;
1255         }
1256 failed:
1257         errflag = 1;
1258         snprintf(errbuf, sizeof errbuf, "Symbol not found: %s", s);
1259         return 0;
1260 }
1261
1262 int __dladdr(void *addr, Dl_info *info)
1263 {
1264         struct dso *p;
1265         Sym *sym;
1266         uint32_t nsym;
1267         char *strings;
1268         size_t i;
1269         void *best = 0;
1270         char *bestname;
1271
1272         pthread_rwlock_rdlock(&lock);
1273         for (p=head; p && (unsigned char *)addr-p->map>p->map_len; p=p->next);
1274         pthread_rwlock_unlock(&lock);
1275
1276         if (!p) return 0;
1277
1278         sym = p->syms;
1279         strings = p->strings;
1280         if (p->hashtab) {
1281                 nsym = p->hashtab[1];
1282         } else {
1283                 uint32_t *buckets;
1284                 uint32_t *hashval;
1285                 buckets = p->ghashtab + 4 + (p->ghashtab[2]*sizeof(size_t)/4);
1286                 sym += p->ghashtab[1];
1287                 for (i = 0; i < p->ghashtab[0]; i++) {
1288                         if (buckets[i] > nsym)
1289                                 nsym = buckets[i];
1290                 }
1291                 if (nsym) {
1292                         nsym -= p->ghashtab[1];
1293                         hashval = buckets + p->ghashtab[0] + nsym;
1294                         do nsym++;
1295                         while (!(*hashval++ & 1));
1296                 }
1297         }
1298
1299         for (; nsym; nsym--, sym++) {
1300                 if (sym->st_value
1301                  && (1<<(sym->st_info&0xf) & OK_TYPES)
1302                  && (1<<(sym->st_info>>4) & OK_BINDS)) {
1303                         void *symaddr = p->base + sym->st_value;
1304                         if (symaddr > addr || symaddr < best)
1305                                 continue;
1306                         best = symaddr;
1307                         bestname = strings + sym->st_name;
1308                         if (addr == symaddr)
1309                                 break;
1310                 }
1311         }
1312
1313         if (!best) return 0;
1314
1315         info->dli_fname = p->name;
1316         info->dli_fbase = p->base;
1317         info->dli_sname = bestname;
1318         info->dli_saddr = best;
1319
1320         return 1;
1321 }
1322
1323 void *__dlsym(void *restrict p, const char *restrict s, void *restrict ra)
1324 {
1325         void *res;
1326         pthread_rwlock_rdlock(&lock);
1327         res = do_dlsym(p, s, ra);
1328         pthread_rwlock_unlock(&lock);
1329         return res;
1330 }
1331
1332 int dl_iterate_phdr(int(*callback)(struct dl_phdr_info *info, size_t size, void *data), void *data)
1333 {
1334         struct dso *current;
1335         struct dl_phdr_info info;
1336         int ret = 0;
1337         for(current = head; current;) {
1338                 info.dlpi_addr      = (uintptr_t)current->base;
1339                 info.dlpi_name      = current->name;
1340                 info.dlpi_phdr      = current->phdr;
1341                 info.dlpi_phnum     = current->phnum;
1342                 info.dlpi_adds      = gencnt;
1343                 info.dlpi_subs      = 0;
1344                 info.dlpi_tls_modid = current->tls_id;
1345                 info.dlpi_tls_data  = current->tls_image;
1346
1347                 ret = (callback)(&info, sizeof (info), data);
1348
1349                 if (ret != 0) break;
1350
1351                 pthread_rwlock_rdlock(&lock);
1352                 current = current->next;
1353                 pthread_rwlock_unlock(&lock);
1354         }
1355         return ret;
1356 }
1357 #else
1358 static int invalid_dso_handle(void *h)
1359 {
1360         snprintf(errbuf, sizeof errbuf, "Invalid library handle %p", (void *)h);
1361         errflag = 1;
1362         return 1;
1363 }
1364 void *dlopen(const char *file, int mode)
1365 {
1366         return 0;
1367 }
1368 void *__dlsym(void *restrict p, const char *restrict s, void *restrict ra)
1369 {
1370         return 0;
1371 }
1372 int __dladdr (void *addr, Dl_info *info)
1373 {
1374         return 0;
1375 }
1376 #endif
1377
1378 int __dlinfo(void *dso, int req, void *res)
1379 {
1380         if (invalid_dso_handle(dso)) return -1;
1381         if (req != RTLD_DI_LINKMAP) {
1382                 snprintf(errbuf, sizeof errbuf, "Unsupported request %d", req);
1383                 errflag = 1;
1384                 return -1;
1385         }
1386         *(struct link_map **)res = dso;
1387         return 0;
1388 }
1389
1390 char *dlerror()
1391 {
1392         if (!errflag) return 0;
1393         errflag = 0;
1394         return errbuf;
1395 }
1396
1397 int dlclose(void *p)
1398 {
1399         return invalid_dso_handle(p);
1400 }