2 #define SYSCALL_NO_TLS 1
20 #include <semaphore.h>
21 #include <sys/membarrier.h>
22 #include "pthread_impl.h"
23 #include "fork_impl.h"
27 #define malloc __libc_malloc
28 #define calloc __libc_calloc
29 #define realloc __libc_realloc
30 #define free __libc_free
32 static void error_impl(const char *, ...);
33 static void error_noop(const char *, ...);
34 static void (*error)(const char *, ...) = error_noop;
36 #define MAXP2(a,b) (-(-(a)&-(b)))
37 #define ALIGN(x,y) ((x)+(y)-1 & -(y))
39 #define container_of(p,t,m) ((t*)((char *)(p)-offsetof(t,m)))
40 #define countof(a) ((sizeof (a))/(sizeof (a)[0]))
52 struct td_index *next;
57 struct fdpic_loadmap *loadmap;
63 struct dso *next, *prev;
73 struct dso *syms_next, *lazy_next;
74 size_t *lazy, lazy_cnt;
85 struct dso **deps, *needed_by;
88 pthread_t ctor_visitor;
89 char *rpath_orig, *rpath;
90 struct tls_module tls;
92 size_t relro_start, relro_end;
94 unsigned char *new_tls;
95 struct td_index *td_index;
96 struct dso *fini_next;
101 struct fdpic_loadmap *loadmap;
116 typedef void (*stage3_func)(size_t *, size_t *);
118 static struct builtin_tls {
123 #define MIN_TLS_ALIGN offsetof(struct builtin_tls, pt)
125 #define ADDEND_LIMIT 4096
126 static size_t *saved_addends, *apply_addends_to;
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;
134 static int ldso_fail;
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;
152 struct debug *_dl_debug_addr = &debug;
154 extern hidden int __malloc_replaced;
156 hidden void (*const __init_array_start)(void)=0, (*const __fini_array_start)(void)=0;
158 extern hidden void (*const __init_array_end)(void), (*const __fini_array_end)(void);
160 weak_alias(__init_array_start, __init_array_end);
161 weak_alias(__fini_array_start, __fini_array_end);
163 static int dl_strcmp(const char *l, const char *r)
165 for (; *l==*r && *l; l++, r++);
166 return *(unsigned char *)l - *(unsigned char *)r;
168 #define strcmp(l,r) dl_strcmp(l,r)
170 /* Compute load address for a virtual address in a given dso. */
172 static void *laddr(const struct dso *p, size_t v)
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);
179 static void *laddr_pg(const struct dso *p, size_t v)
182 size_t pgsz = PAGE_SIZE;
183 if (!p->loadmap) return p->base + v;
185 size_t a = p->loadmap->segs[j].p_vaddr;
186 size_t b = a + p->loadmap->segs[j].p_memsz;
192 return (void *)(v - p->loadmap->segs[j].p_vaddr + p->loadmap->segs[j].addr);
194 static void (*fdbarrier(void *p))()
197 __asm__("" : "=r"(fd) : "0"(p));
200 #define fpaddr(p, v) fdbarrier((&(struct funcdesc){ \
201 laddr(p, v), (p)->got }))
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))
208 static void decode_vec(size_t *v, size_t *a, size_t cnt)
211 for (i=0; i<cnt; i++) a[i] = 0;
212 for (; v[0]; v+=2) if (v[0]-1<cnt-1) {
213 if (v[0] < 8*sizeof(long))
219 static int search_vec(size_t *v, size_t *r, size_t key)
221 for (; v[0]!=key; v+=2)
227 static uint32_t sysv_hash(const char *s0)
229 const unsigned char *s = (void *)s0;
235 return h & 0xfffffff;
238 static uint32_t gnu_hash(const char *s0)
240 const unsigned char *s = (void *)s0;
241 uint_fast32_t h = 5381;
247 static Sym *sysv_lookup(const char *s, uint32_t h, struct dso *dso)
250 Sym *syms = dso->syms;
251 Elf_Symndx *hashtab = dso->hashtab;
252 char *strings = dso->strings;
253 for (i=hashtab[2+h%hashtab[0]]; i; i=hashtab[2+hashtab[0]+i]) {
254 if ((!dso->versym || dso->versym[i] >= 0)
255 && (!strcmp(s, strings+syms[i].st_name)))
261 static Sym *gnu_lookup(uint32_t h1, uint32_t *hashtab, struct dso *dso, const char *s)
263 uint32_t nbuckets = hashtab[0];
264 uint32_t *buckets = hashtab + 4 + hashtab[2]*(sizeof(size_t)/4);
265 uint32_t i = buckets[h1 % nbuckets];
269 uint32_t *hashval = buckets + nbuckets + (i - hashtab[1]);
271 for (h1 |= 1; ; i++) {
272 uint32_t h2 = *hashval++;
273 if ((h1 == (h2|1)) && (!dso->versym || dso->versym[i] >= 0)
274 && !strcmp(s, dso->strings + dso->syms[i].st_name))
282 static Sym *gnu_lookup_filtered(uint32_t h1, uint32_t *hashtab, struct dso *dso, const char *s, uint32_t fofs, size_t fmask)
284 const size_t *bloomwords = (const void *)(hashtab+4);
285 size_t f = bloomwords[fofs & (hashtab[2]-1)];
286 if (!(f & fmask)) return 0;
288 f >>= (h1 >> hashtab[3]) % (8 * sizeof f);
289 if (!(f & 1)) return 0;
291 return gnu_lookup(h1, hashtab, dso, s);
294 #define OK_TYPES (1<<STT_NOTYPE | 1<<STT_OBJECT | 1<<STT_FUNC | 1<<STT_COMMON | 1<<STT_TLS)
295 #define OK_BINDS (1<<STB_GLOBAL | 1<<STB_WEAK | 1<<STB_GNU_UNIQUE)
297 #ifndef ARCH_SYM_REJECT_UND
298 #define ARCH_SYM_REJECT_UND(s) 0
301 #if defined(__GNUC__)
302 __attribute__((always_inline))
304 static inline struct symdef find_sym2(struct dso *dso, const char *s, int need_def, int use_deps)
306 uint32_t h = 0, gh = gnu_hash(s), gho = gh / (8*sizeof(size_t)), *ght;
307 size_t ghm = 1ul << gh % (8*sizeof(size_t));
308 struct symdef def = {0};
309 struct dso **deps = use_deps ? dso->deps : 0;
310 for (; dso; dso=use_deps ? *deps++ : dso->syms_next) {
312 if ((ght = dso->ghashtab)) {
313 sym = gnu_lookup_filtered(gh, ght, dso, s, gho, ghm);
315 if (!h) h = sysv_hash(s);
316 sym = sysv_lookup(s, h, dso);
320 if (need_def || (sym->st_info&0xf) == STT_TLS
321 || ARCH_SYM_REJECT_UND(sym))
324 if ((sym->st_info&0xf) != STT_TLS)
326 if (!(1<<(sym->st_info&0xf) & OK_TYPES)) continue;
327 if (!(1<<(sym->st_info>>4) & OK_BINDS)) continue;
335 static struct symdef find_sym(struct dso *dso, const char *s, int need_def)
337 return find_sym2(dso, s, need_def, 0);
340 static void do_relocs(struct dso *dso, size_t *rel, size_t rel_size, size_t stride)
342 unsigned char *base = dso->base;
343 Sym *syms = dso->syms;
344 char *strings = dso->strings;
355 int skip_relative = 0, reuse_addends = 0, save_slot = 0;
358 /* Only ldso's REL table needs addend saving/reuse. */
359 if (rel == apply_addends_to)
364 for (; rel_size; rel+=stride, rel_size-=stride*sizeof(size_t)) {
365 if (skip_relative && IS_RELATIVE(rel[1], dso->syms)) continue;
366 type = R_TYPE(rel[1]);
367 if (type == REL_NONE) continue;
368 reloc_addr = laddr(dso, rel[0]);
372 } else if (type==REL_GOT || type==REL_PLT|| type==REL_COPY) {
374 } else if (reuse_addends) {
375 /* Save original addend in stage 2 where the dso
376 * chain consists of just ldso; otherwise read back
377 * saved addend since the inline one was clobbered. */
379 saved_addends[save_slot] = *reloc_addr;
380 addend = saved_addends[save_slot++];
382 addend = *reloc_addr;
385 sym_index = R_SYM(rel[1]);
387 sym = syms + sym_index;
388 name = strings + sym->st_name;
389 ctx = type==REL_COPY ? head->syms_next : head;
390 def = (sym->st_info>>4) == STB_LOCAL
391 ? (struct symdef){ .dso = dso, .sym = sym }
392 : find_sym(ctx, name, type==REL_PLT);
393 if (!def.sym && (sym->st_shndx != SHN_UNDEF
394 || sym->st_info>>4 != STB_WEAK)) {
395 if (dso->lazy && (type==REL_PLT || type==REL_GOT)) {
396 dso->lazy[3*dso->lazy_cnt+0] = rel[0];
397 dso->lazy[3*dso->lazy_cnt+1] = rel[1];
398 dso->lazy[3*dso->lazy_cnt+2] = addend;
402 error("Error relocating %s: %s: symbol not found",
404 if (runtime) longjmp(*rtld_fail, 1);
413 sym_val = def.sym ? (size_t)laddr(def.dso, def.sym->st_value) : 0;
414 tls_val = def.sym ? def.sym->st_value : 0;
416 if ((type == REL_TPOFF || type == REL_TPOFF_NEG)
417 && def.dso->tls_id > static_tls_cnt) {
418 error("Error relocating %s: %s: initial-exec TLS "
419 "resolves to dynamic definition in %s",
420 dso->name, name, def.dso->name);
421 longjmp(*rtld_fail, 1);
426 addend -= (size_t)reloc_addr;
430 *reloc_addr = sym_val + addend;
433 memcpy(reloc_addr, &(size_t){sym_val + addend}, sizeof(size_t));
436 *reloc_addr = (size_t)base + addend;
439 if (sym) *reloc_addr = sym_val + addend;
440 else *reloc_addr = (size_t)base + addend;
443 memcpy(reloc_addr, (void *)sym_val, sym->st_size);
446 *(uint32_t *)reloc_addr = sym_val + addend
447 - (size_t)reloc_addr;
450 *reloc_addr = def.sym ? (size_t)(def.dso->funcdescs
451 + (def.sym - def.dso->syms)) : 0;
453 case REL_FUNCDESC_VAL:
454 if ((sym->st_info&0xf) == STT_SECTION) *reloc_addr += sym_val;
455 else *reloc_addr = sym_val;
456 reloc_addr[1] = def.sym ? (size_t)def.dso->got : 0;
459 *reloc_addr = def.dso->tls_id;
462 *reloc_addr = tls_val + addend - DTP_OFFSET;
466 *reloc_addr = tls_val + def.dso->tls.offset + TPOFF_K + addend;
470 *reloc_addr = tls_val - def.dso->tls.offset + addend;
473 *reloc_addr = def.dso->tls.offset - tls_val + addend;
477 if (stride<3) addend = reloc_addr[1];
478 if (def.dso->tls_id > static_tls_cnt) {
479 struct td_index *new = malloc(sizeof *new);
482 "Error relocating %s: cannot allocate TLSDESC for %s",
483 dso->name, sym ? name : "(local)" );
484 longjmp(*rtld_fail, 1);
486 new->next = dso->td_index;
488 new->args[0] = def.dso->tls_id;
489 new->args[1] = tls_val + addend - DTP_OFFSET;
490 reloc_addr[0] = (size_t)__tlsdesc_dynamic;
491 reloc_addr[1] = (size_t)new;
493 reloc_addr[0] = (size_t)__tlsdesc_static;
495 reloc_addr[1] = tls_val + def.dso->tls.offset
498 reloc_addr[1] = tls_val - def.dso->tls.offset
502 #ifdef TLSDESC_BACKWARDS
503 /* Some archs (32-bit ARM at least) invert the order of
504 * the descriptor members. Fix them up here. */
505 size_t tmp = reloc_addr[0];
506 reloc_addr[0] = reloc_addr[1];
511 error("Error relocating %s: unsupported relocation type %d",
513 if (runtime) longjmp(*rtld_fail, 1);
519 static void do_relr_relocs(struct dso *dso, size_t *relr, size_t relr_size)
521 unsigned char *base = dso->base;
523 for (; relr_size; relr++, relr_size-=sizeof(size_t))
524 if ((relr[0]&1) == 0) {
525 reloc_addr = laddr(dso, relr[0]);
526 *reloc_addr++ += (size_t)base;
529 for (size_t bitmap=relr[0]; (bitmap>>=1); i++)
531 reloc_addr[i] += (size_t)base;
532 reloc_addr += 8*sizeof(size_t)-1;
536 static void redo_lazy_relocs()
538 struct dso *p = lazy_head, *next;
542 size_t size = p->lazy_cnt*3*sizeof(size_t);
544 do_relocs(p, p->lazy, size, 3);
546 p->lazy_next = lazy_head;
556 /* A huge hack: to make up for the wastefulness of shared libraries
557 * needing at least a page of dirty memory even if they have no global
558 * data, we reclaim the gaps at the beginning and end of writable maps
559 * and "donate" them to the heap. */
561 static void reclaim(struct dso *dso, size_t start, size_t end)
563 if (start >= dso->relro_start && start < dso->relro_end) start = dso->relro_end;
564 if (end >= dso->relro_start && end < dso->relro_end) end = dso->relro_start;
565 if (start >= end) return;
566 char *base = laddr_pg(dso, start);
567 __malloc_donate(base, base+(end-start));
570 static void reclaim_gaps(struct dso *dso)
572 Phdr *ph = dso->phdr;
573 size_t phcnt = dso->phnum;
575 for (; phcnt--; ph=(void *)((char *)ph+dso->phentsize)) {
576 if (ph->p_type!=PT_LOAD) continue;
577 if ((ph->p_flags&(PF_R|PF_W))!=(PF_R|PF_W)) continue;
578 reclaim(dso, ph->p_vaddr & -PAGE_SIZE, ph->p_vaddr);
579 reclaim(dso, ph->p_vaddr+ph->p_memsz,
580 ph->p_vaddr+ph->p_memsz+PAGE_SIZE-1 & -PAGE_SIZE);
584 static ssize_t read_loop(int fd, void *p, size_t n)
586 for (size_t i=0; i<n; ) {
587 ssize_t l = read(fd, (char *)p+i, n-i);
589 if (errno==EINTR) continue;
598 static void *mmap_fixed(void *p, size_t n, int prot, int flags, int fd, off_t off)
600 static int no_map_fixed;
604 q = mmap(p, n, prot, flags|MAP_FIXED, fd, off);
605 if (!DL_NOMMU_SUPPORT || q != MAP_FAILED || errno != EINVAL)
609 /* Fallbacks for MAP_FIXED failure on NOMMU kernels. */
610 if (flags & MAP_ANONYMOUS) {
615 if (lseek(fd, off, SEEK_SET) < 0) return MAP_FAILED;
616 for (q=p; n; q+=r, off+=r, n-=r) {
618 if (r < 0 && errno != EINTR) return MAP_FAILED;
627 static void unmap_library(struct dso *dso)
631 for (i=0; i<dso->loadmap->nsegs; i++) {
632 if (!dso->loadmap->segs[i].p_memsz)
634 munmap((void *)dso->loadmap->segs[i].addr,
635 dso->loadmap->segs[i].p_memsz);
638 } else if (dso->map && dso->map_len) {
639 munmap(dso->map, dso->map_len);
643 static void *map_library(int fd, struct dso *dso)
645 Ehdr buf[(896+sizeof(Ehdr))/sizeof(Ehdr)];
646 void *allocated_buf=0;
648 size_t addr_min=SIZE_MAX, addr_max=0, map_len;
649 size_t this_min, this_max;
655 unsigned char *map=MAP_FAILED, *base;
660 ssize_t l = read(fd, buf, sizeof buf);
663 if (l<sizeof *eh || (eh->e_type != ET_DYN && eh->e_type != ET_EXEC))
665 phsize = eh->e_phentsize * eh->e_phnum;
666 if (phsize > sizeof buf - sizeof *eh) {
667 allocated_buf = malloc(phsize);
668 if (!allocated_buf) return 0;
669 l = pread(fd, allocated_buf, phsize, eh->e_phoff);
670 if (l < 0) goto error;
671 if (l != phsize) goto noexec;
672 ph = ph0 = allocated_buf;
673 } else if (eh->e_phoff + phsize > l) {
674 l = pread(fd, buf+1, phsize, eh->e_phoff);
675 if (l < 0) goto error;
676 if (l != phsize) goto noexec;
677 ph = ph0 = (void *)(buf + 1);
679 ph = ph0 = (void *)((char *)buf + eh->e_phoff);
681 for (i=eh->e_phnum; i; i--, ph=(void *)((char *)ph+eh->e_phentsize)) {
682 if (ph->p_type == PT_DYNAMIC) {
684 } else if (ph->p_type == PT_TLS) {
685 tls_image = ph->p_vaddr;
686 dso->tls.align = ph->p_align;
687 dso->tls.len = ph->p_filesz;
688 dso->tls.size = ph->p_memsz;
689 } else if (ph->p_type == PT_GNU_RELRO) {
690 dso->relro_start = ph->p_vaddr & -PAGE_SIZE;
691 dso->relro_end = (ph->p_vaddr + ph->p_memsz) & -PAGE_SIZE;
692 } else if (ph->p_type == PT_GNU_STACK) {
693 if (!runtime && ph->p_memsz > __default_stacksize) {
694 __default_stacksize =
695 ph->p_memsz < DEFAULT_STACK_MAX ?
696 ph->p_memsz : DEFAULT_STACK_MAX;
699 if (ph->p_type != PT_LOAD) continue;
701 if (ph->p_vaddr < addr_min) {
702 addr_min = ph->p_vaddr;
703 off_start = ph->p_offset;
704 prot = (((ph->p_flags&PF_R) ? PROT_READ : 0) |
705 ((ph->p_flags&PF_W) ? PROT_WRITE: 0) |
706 ((ph->p_flags&PF_X) ? PROT_EXEC : 0));
708 if (ph->p_vaddr+ph->p_memsz > addr_max) {
709 addr_max = ph->p_vaddr+ph->p_memsz;
712 if (!dyn) goto noexec;
713 if (DL_FDPIC && !(eh->e_flags & FDPIC_CONSTDISP_FLAG)) {
714 dso->loadmap = calloc(1, sizeof *dso->loadmap
715 + nsegs * sizeof *dso->loadmap->segs);
716 if (!dso->loadmap) goto error;
717 dso->loadmap->nsegs = nsegs;
718 for (ph=ph0, i=0; i<nsegs; ph=(void *)((char *)ph+eh->e_phentsize)) {
719 if (ph->p_type != PT_LOAD) continue;
720 prot = (((ph->p_flags&PF_R) ? PROT_READ : 0) |
721 ((ph->p_flags&PF_W) ? PROT_WRITE: 0) |
722 ((ph->p_flags&PF_X) ? PROT_EXEC : 0));
723 map = mmap(0, ph->p_memsz + (ph->p_vaddr & PAGE_SIZE-1),
725 fd, ph->p_offset & -PAGE_SIZE);
726 if (map == MAP_FAILED) {
730 dso->loadmap->segs[i].addr = (size_t)map +
731 (ph->p_vaddr & PAGE_SIZE-1);
732 dso->loadmap->segs[i].p_vaddr = ph->p_vaddr;
733 dso->loadmap->segs[i].p_memsz = ph->p_memsz;
735 if (prot & PROT_WRITE) {
736 size_t brk = (ph->p_vaddr & PAGE_SIZE-1)
738 size_t pgbrk = brk + PAGE_SIZE-1 & -PAGE_SIZE;
739 size_t pgend = brk + ph->p_memsz - ph->p_filesz
740 + PAGE_SIZE-1 & -PAGE_SIZE;
741 if (pgend > pgbrk && mmap_fixed(map+pgbrk,
743 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS,
744 -1, off_start) == MAP_FAILED)
746 memset(map + brk, 0, pgbrk-brk);
749 map = (void *)dso->loadmap->segs[0].addr;
753 addr_max += PAGE_SIZE-1;
754 addr_max &= -PAGE_SIZE;
755 addr_min &= -PAGE_SIZE;
756 off_start &= -PAGE_SIZE;
757 map_len = addr_max - addr_min + off_start;
758 /* The first time, we map too much, possibly even more than
759 * the length of the file. This is okay because we will not
760 * use the invalid part; we just need to reserve the right
761 * amount of virtual address space to map over later. */
762 map = DL_NOMMU_SUPPORT
763 ? mmap((void *)addr_min, map_len, PROT_READ|PROT_WRITE|PROT_EXEC,
764 MAP_PRIVATE|MAP_ANONYMOUS, -1, 0)
765 : mmap((void *)addr_min, map_len, prot,
766 MAP_PRIVATE, fd, off_start);
767 if (map==MAP_FAILED) goto error;
769 dso->map_len = map_len;
770 /* If the loaded file is not relocatable and the requested address is
771 * not available, then the load operation must fail. */
772 if (eh->e_type != ET_DYN && addr_min && map!=(void *)addr_min) {
776 base = map - addr_min;
779 for (ph=ph0, i=eh->e_phnum; i; i--, ph=(void *)((char *)ph+eh->e_phentsize)) {
780 if (ph->p_type != PT_LOAD) continue;
781 /* Check if the programs headers are in this load segment, and
782 * if so, record the address for use by dl_iterate_phdr. */
783 if (!dso->phdr && eh->e_phoff >= ph->p_offset
784 && eh->e_phoff+phsize <= ph->p_offset+ph->p_filesz) {
785 dso->phdr = (void *)(base + ph->p_vaddr
786 + (eh->e_phoff-ph->p_offset));
787 dso->phnum = eh->e_phnum;
788 dso->phentsize = eh->e_phentsize;
790 this_min = ph->p_vaddr & -PAGE_SIZE;
791 this_max = ph->p_vaddr+ph->p_memsz+PAGE_SIZE-1 & -PAGE_SIZE;
792 off_start = ph->p_offset & -PAGE_SIZE;
793 prot = (((ph->p_flags&PF_R) ? PROT_READ : 0) |
794 ((ph->p_flags&PF_W) ? PROT_WRITE: 0) |
795 ((ph->p_flags&PF_X) ? PROT_EXEC : 0));
796 /* Reuse the existing mapping for the lowest-address LOAD */
797 if ((ph->p_vaddr & -PAGE_SIZE) != addr_min || DL_NOMMU_SUPPORT)
798 if (mmap_fixed(base+this_min, this_max-this_min, prot, MAP_PRIVATE|MAP_FIXED, fd, off_start) == MAP_FAILED)
800 if (ph->p_memsz > ph->p_filesz && (ph->p_flags&PF_W)) {
801 size_t brk = (size_t)base+ph->p_vaddr+ph->p_filesz;
802 size_t pgbrk = brk+PAGE_SIZE-1 & -PAGE_SIZE;
803 memset((void *)brk, 0, pgbrk-brk & PAGE_SIZE-1);
804 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)
808 for (i=0; ((size_t *)(base+dyn))[i]; i+=2)
809 if (((size_t *)(base+dyn))[i]==DT_TEXTREL) {
810 if (mprotect(map, map_len, PROT_READ|PROT_WRITE|PROT_EXEC)
817 dso->dynv = laddr(dso, dyn);
818 if (dso->tls.size) dso->tls.image = laddr(dso, tls_image);
824 if (map!=MAP_FAILED) unmap_library(dso);
829 static int path_open(const char *name, const char *s, char *buf, size_t buf_size)
834 s += strspn(s, ":\n");
835 l = strcspn(s, ":\n");
836 if (l-1 >= INT_MAX) return -1;
837 if (snprintf(buf, buf_size, "%.*s/%s", (int)l, s, name) < buf_size) {
838 if ((fd = open(buf, O_RDONLY|O_CLOEXEC))>=0) return fd;
846 /* Any negative value but -1 will inhibit
847 * futher path search. */
855 static int fixup_rpath(struct dso *p, char *buf, size_t buf_size)
858 const char *s, *t, *origin;
860 if (p->rpath || !p->rpath_orig) return 0;
861 if (!strchr(p->rpath_orig, '$')) {
862 p->rpath = p->rpath_orig;
867 while ((t=strchr(s, '$'))) {
868 if (strncmp(t, "$ORIGIN", 7) && strncmp(t, "${ORIGIN}", 9))
873 if (n > SSIZE_MAX/PATH_MAX) return 0;
875 if (p->kernel_mapped) {
876 /* $ORIGIN searches cannot be performed for the main program
877 * when it is suid/sgid/AT_SECURE. This is because the
878 * pathname is under the control of the caller of execve.
879 * For libraries, however, $ORIGIN can be processed safely
880 * since the library's pathname came from a trusted source
881 * (either system paths or a call to dlopen). */
884 l = readlink("/proc/self/exe", buf, buf_size);
885 if (l == -1) switch (errno) {
900 t = strrchr(origin, '/');
904 /* Normally p->name will always be an absolute or relative
905 * pathname containing at least one '/' character, but in the
906 * case where ldso was invoked as a command to execute a
907 * program in the working directory, app.name may not. Fix. */
911 /* Disallow non-absolute origins for suid/sgid/AT_SECURE. */
912 if (libc.secure && *origin != '/')
914 p->rpath = malloc(strlen(p->rpath_orig) + n*l + 1);
915 if (!p->rpath) return -1;
919 while ((t=strchr(s, '$'))) {
922 memcpy(d, origin, l);
924 /* It was determined previously that the '$' is followed
925 * either by "ORIGIN" or "{ORIGIN}". */
926 s = t + 7 + 2*(t[1]=='{');
932 static void decode_dyn(struct dso *p)
935 decode_vec(p->dynv, dyn, DYN_CNT);
936 p->syms = laddr(p, dyn[DT_SYMTAB]);
937 p->strings = laddr(p, dyn[DT_STRTAB]);
938 if (dyn[0]&(1<<DT_HASH))
939 p->hashtab = laddr(p, dyn[DT_HASH]);
940 if (dyn[0]&(1<<DT_RPATH))
941 p->rpath_orig = p->strings + dyn[DT_RPATH];
942 if (dyn[0]&(1<<DT_RUNPATH))
943 p->rpath_orig = p->strings + dyn[DT_RUNPATH];
944 if (dyn[0]&(1<<DT_PLTGOT))
945 p->got = laddr(p, dyn[DT_PLTGOT]);
946 if (search_vec(p->dynv, dyn, DT_GNU_HASH))
947 p->ghashtab = laddr(p, *dyn);
948 if (search_vec(p->dynv, dyn, DT_VERSYM))
949 p->versym = laddr(p, *dyn);
952 static size_t count_syms(struct dso *p)
954 if (p->hashtab) return p->hashtab[1];
957 uint32_t *buckets = p->ghashtab + 4 + (p->ghashtab[2]*sizeof(size_t)/4);
959 for (i = nsym = 0; i < p->ghashtab[0]; i++) {
960 if (buckets[i] > nsym)
964 hashval = buckets + p->ghashtab[0] + (nsym - p->ghashtab[1]);
966 while (!(*hashval++ & 1));
971 static void *dl_mmap(size_t n)
974 int prot = PROT_READ|PROT_WRITE, flags = MAP_ANONYMOUS|MAP_PRIVATE;
976 p = (void *)__syscall(SYS_mmap2, 0, n, prot, flags, -1, 0);
978 p = (void *)__syscall(SYS_mmap, 0, n, prot, flags, -1, 0);
980 return (unsigned long)p > -4096UL ? 0 : p;
983 static void makefuncdescs(struct dso *p)
985 static int self_done;
986 size_t nsym = count_syms(p);
987 size_t i, size = nsym * sizeof(*p->funcdescs);
990 p->funcdescs = dl_mmap(size);
993 p->funcdescs = malloc(size);
996 if (!runtime) a_crash();
997 error("Error allocating function descriptors for %s", p->name);
998 longjmp(*rtld_fail, 1);
1000 for (i=0; i<nsym; i++) {
1001 if ((p->syms[i].st_info&0xf)==STT_FUNC && p->syms[i].st_shndx) {
1002 p->funcdescs[i].addr = laddr(p, p->syms[i].st_value);
1003 p->funcdescs[i].got = p->got;
1005 p->funcdescs[i].addr = 0;
1006 p->funcdescs[i].got = 0;
1011 static struct dso *load_library(const char *name, struct dso *needed_by)
1013 char buf[2*NAME_MAX+2];
1014 const char *pathname;
1016 struct dso *p, temp_dso = {0};
1028 /* Catch and block attempts to reload the implementation itself */
1029 if (name[0]=='l' && name[1]=='i' && name[2]=='b') {
1030 static const char reserved[] =
1031 "c.pthread.rt.m.dl.util.xnet.";
1032 const char *rp, *next;
1033 for (rp=reserved; *rp; rp=next) {
1034 next = strchr(rp, '.') + 1;
1035 if (strncmp(name+3, rp, next-rp) == 0)
1040 /* Track which names have been resolved
1041 * and only report each one once. */
1042 static unsigned reported;
1043 unsigned mask = 1U<<(rp-reserved);
1044 if (!(reported & mask)) {
1046 dprintf(1, "\t%s => %s (%p)\n",
1054 if (!strcmp(name, ldso.name)) is_self = 1;
1063 if (strchr(name, '/')) {
1065 fd = open(name, O_RDONLY|O_CLOEXEC);
1067 /* Search for the name to see if it's already loaded */
1068 for (p=head->next; p; p=p->next) {
1069 if (p->shortname && !strcmp(p->shortname, name)) {
1073 if (strlen(name) > NAME_MAX) return 0;
1075 if (env_path) fd = path_open(name, env_path, buf, sizeof buf);
1076 for (p=needed_by; fd == -1 && p; p=p->needed_by) {
1077 if (fixup_rpath(p, buf, sizeof buf) < 0)
1078 fd = -2; /* Inhibit further search. */
1080 fd = path_open(name, p->rpath, buf, sizeof buf);
1086 if (ldso.name[0]=='/') {
1088 for (s=t=z=ldso.name; *s; s++)
1089 if (*s=='/') z=t, t=s;
1090 prefix_len = z-ldso.name;
1091 if (prefix_len < PATH_MAX)
1098 char etc_ldso_path[prefix_len + 1
1099 + sizeof "/etc/ld-musl-" LDSO_ARCH ".path"];
1100 snprintf(etc_ldso_path, sizeof etc_ldso_path,
1101 "%.*s/etc/ld-musl-" LDSO_ARCH ".path",
1102 (int)prefix_len, prefix);
1103 fd = open(etc_ldso_path, O_RDONLY|O_CLOEXEC);
1106 if (!fstat(fd, &st)) n = st.st_size;
1107 if ((sys_path = malloc(n+1)))
1109 if (!sys_path || read_loop(fd, sys_path, n)<0) {
1114 } else if (errno != ENOENT) {
1118 if (!sys_path) sys_path = "/lib:/usr/local/lib:/usr/lib";
1119 fd = path_open(name, sys_path, buf, sizeof buf);
1123 if (fd < 0) return 0;
1124 if (fstat(fd, &st) < 0) {
1128 for (p=head->next; p; p=p->next) {
1129 if (p->dev == st.st_dev && p->ino == st.st_ino) {
1130 /* If this library was previously loaded with a
1131 * pathname but a search found the same inode,
1132 * setup its shortname so it can be found by name. */
1133 if (!p->shortname && pathname != name)
1134 p->shortname = strrchr(p->name, '/')+1;
1139 map = noload ? 0 : map_library(fd, &temp_dso);
1143 /* Avoid the danger of getting two versions of libc mapped into the
1144 * same process when an absolute pathname was used. The symbols
1145 * checked are chosen to catch both musl and glibc, and to avoid
1146 * false positives from interposition-hack libraries. */
1147 decode_dyn(&temp_dso);
1148 if (find_sym(&temp_dso, "__libc_start_main", 1).sym &&
1149 find_sym(&temp_dso, "stdin", 1).sym) {
1150 unmap_library(&temp_dso);
1151 return load_library("libc.so", needed_by);
1153 /* Past this point, if we haven't reached runtime yet, ldso has
1154 * committed either to use the mapped library or to abort execution.
1155 * Unmapping is not possible, so we can safely reclaim gaps. */
1156 if (!runtime) reclaim_gaps(&temp_dso);
1158 /* Allocate storage for the new DSO. When there is TLS, this
1159 * storage must include a reservation for all pre-existing
1160 * threads to obtain copies of both the new TLS, and an
1161 * extended DTV capable of storing an additional slot for
1162 * the newly-loaded DSO. */
1163 alloc_size = sizeof *p + strlen(pathname) + 1;
1164 if (runtime && temp_dso.tls.image) {
1165 size_t per_th = temp_dso.tls.size + temp_dso.tls.align
1166 + sizeof(void *) * (tls_cnt+3);
1167 n_th = libc.threads_minus_1 + 1;
1168 if (n_th > SSIZE_MAX / per_th) alloc_size = SIZE_MAX;
1169 else alloc_size += n_th * per_th;
1171 p = calloc(1, alloc_size);
1173 unmap_library(&temp_dso);
1176 memcpy(p, &temp_dso, sizeof temp_dso);
1179 p->needed_by = needed_by;
1181 p->runtime_loaded = runtime;
1182 strcpy(p->name, pathname);
1183 /* Add a shortname only if name arg was not an explicit pathname. */
1184 if (pathname != name) p->shortname = strrchr(p->name, '/')+1;
1186 p->tls_id = ++tls_cnt;
1187 tls_align = MAXP2(tls_align, p->tls.align);
1189 p->tls.offset = tls_offset + ( (p->tls.align-1) &
1190 (-tls_offset + (uintptr_t)p->tls.image) );
1191 tls_offset = p->tls.offset + p->tls.size;
1193 tls_offset += p->tls.size + p->tls.align - 1;
1194 tls_offset -= (tls_offset + (uintptr_t)p->tls.image)
1196 p->tls.offset = tls_offset;
1198 p->new_dtv = (void *)(-sizeof(size_t) &
1199 (uintptr_t)(p->name+strlen(p->name)+sizeof(size_t)));
1200 p->new_tls = (void *)(p->new_dtv + n_th*(tls_cnt+1));
1201 if (tls_tail) tls_tail->next = &p->tls;
1202 else libc.tls_head = &p->tls;
1210 if (DL_FDPIC) makefuncdescs(p);
1212 if (ldd_mode) dprintf(1, "\t%s => %s (%p)\n", name, pathname, p->base);
1217 static void load_direct_deps(struct dso *p)
1221 if (p->deps) return;
1222 /* For head, all preloads are direct pseudo-dependencies.
1223 * Count and include them now to avoid realloc later. */
1224 if (p==head) for (struct dso *q=p->next; q; q=q->next)
1226 for (i=0; p->dynv[i]; i+=2)
1227 if (p->dynv[i] == DT_NEEDED) cnt++;
1228 /* Use builtin buffer for apps with no external deps, to
1229 * preserve property of no runtime failure paths. */
1230 p->deps = (p==head && cnt<2) ? builtin_deps :
1231 calloc(cnt+1, sizeof *p->deps);
1233 error("Error loading dependencies for %s", p->name);
1234 if (runtime) longjmp(*rtld_fail, 1);
1237 if (p==head) for (struct dso *q=p->next; q; q=q->next)
1239 for (i=0; p->dynv[i]; i+=2) {
1240 if (p->dynv[i] != DT_NEEDED) continue;
1241 struct dso *dep = load_library(p->strings + p->dynv[i+1], p);
1243 error("Error loading shared library %s: %m (needed by %s)",
1244 p->strings + p->dynv[i+1], p->name);
1245 if (runtime) longjmp(*rtld_fail, 1);
1248 p->deps[cnt++] = dep;
1251 p->ndeps_direct = cnt;
1254 static void load_deps(struct dso *p)
1256 if (p->deps) return;
1257 for (; p; p=p->next)
1258 load_direct_deps(p);
1261 static void extend_bfs_deps(struct dso *p)
1263 size_t i, j, cnt, ndeps_all;
1266 /* Can't use realloc if the original p->deps was allocated at
1267 * program entry and malloc has been replaced, or if it's
1268 * the builtin non-allocated trivial main program deps array. */
1269 int no_realloc = (__malloc_replaced && !p->runtime_loaded)
1270 || p->deps == builtin_deps;
1272 if (p->bfs_built) return;
1273 ndeps_all = p->ndeps_direct;
1275 /* Mark existing (direct) deps so they won't be duplicated. */
1276 for (i=0; p->deps[i]; i++)
1277 p->deps[i]->mark = 1;
1279 /* For each dependency already in the list, copy its list of direct
1280 * dependencies to the list, excluding any items already in the
1281 * list. Note that the list this loop iterates over will grow during
1282 * the loop, but since duplicates are excluded, growth is bounded. */
1283 for (i=0; p->deps[i]; i++) {
1284 struct dso *dep = p->deps[i];
1285 for (j=cnt=0; j<dep->ndeps_direct; j++)
1286 if (!dep->deps[j]->mark) cnt++;
1288 malloc(sizeof(*tmp) * (ndeps_all+cnt+1)) :
1289 realloc(p->deps, sizeof(*tmp) * (ndeps_all+cnt+1));
1291 error("Error recording dependencies for %s", p->name);
1292 if (runtime) longjmp(*rtld_fail, 1);
1296 memcpy(tmp, p->deps, sizeof(*tmp) * (ndeps_all+1));
1300 for (j=0; j<dep->ndeps_direct; j++) {
1301 if (dep->deps[j]->mark) continue;
1302 dep->deps[j]->mark = 1;
1303 p->deps[ndeps_all++] = dep->deps[j];
1305 p->deps[ndeps_all] = 0;
1308 for (p=head; p; p=p->next)
1312 static void load_preload(char *s)
1316 for (z=s; *z; s=z) {
1317 for ( ; *s && (isspace(*s) || *s==':'); s++);
1318 for (z=s; *z && !isspace(*z) && *z!=':'; z++);
1326 static void add_syms(struct dso *p)
1328 if (!p->syms_next && syms_tail != p) {
1329 syms_tail->syms_next = p;
1334 static void revert_syms(struct dso *old_tail)
1336 struct dso *p, *next;
1337 /* Chop off the tail of the list of dsos that participate in
1338 * the global symbol table, reverting them to RTLD_LOCAL. */
1339 for (p=old_tail; p; p=next) {
1340 next = p->syms_next;
1343 syms_tail = old_tail;
1346 static void do_mips_relocs(struct dso *p, size_t *got)
1348 size_t i, j, rel[2];
1349 unsigned char *base = p->base;
1350 i=0; search_vec(p->dynv, &i, DT_MIPS_LOCAL_GOTNO);
1354 while (i--) *got++ += (size_t)base;
1356 j=0; search_vec(p->dynv, &j, DT_MIPS_GOTSYM);
1357 i=0; search_vec(p->dynv, &i, DT_MIPS_SYMTABNO);
1358 Sym *sym = p->syms + j;
1359 rel[0] = (unsigned char *)got - base;
1360 for (i-=j; i; i--, sym++, rel[0]+=sizeof(size_t)) {
1361 rel[1] = R_INFO(sym-p->syms, R_MIPS_JUMP_SLOT);
1362 do_relocs(p, rel, sizeof rel, 2);
1366 static void reloc_all(struct dso *p)
1368 size_t dyn[DYN_CNT];
1369 for (; p; p=p->next) {
1370 if (p->relocated) continue;
1371 decode_vec(p->dynv, dyn, DYN_CNT);
1372 if (NEED_MIPS_GOT_RELOCS)
1373 do_mips_relocs(p, laddr(p, dyn[DT_PLTGOT]));
1374 do_relocs(p, laddr(p, dyn[DT_JMPREL]), dyn[DT_PLTRELSZ],
1375 2+(dyn[DT_PLTREL]==DT_RELA));
1376 do_relocs(p, laddr(p, dyn[DT_REL]), dyn[DT_RELSZ], 2);
1377 do_relocs(p, laddr(p, dyn[DT_RELA]), dyn[DT_RELASZ], 3);
1378 do_relr_relocs(p, laddr(p, dyn[DT_RELR]), dyn[DT_RELRSZ]);
1380 if (head != &ldso && p->relro_start != p->relro_end) {
1381 long ret = __syscall(SYS_mprotect, laddr(p, p->relro_start),
1382 p->relro_end-p->relro_start, PROT_READ);
1383 if (ret != 0 && ret != -ENOSYS) {
1384 error("Error relocating %s: RELRO protection failed: %m",
1386 if (runtime) longjmp(*rtld_fail, 1);
1394 static void kernel_mapped_dso(struct dso *p)
1396 size_t min_addr = -1, max_addr = 0, cnt;
1398 for (cnt = p->phnum; cnt--; ph = (void *)((char *)ph + p->phentsize)) {
1399 if (ph->p_type == PT_DYNAMIC) {
1400 p->dynv = laddr(p, ph->p_vaddr);
1401 } else if (ph->p_type == PT_GNU_RELRO) {
1402 p->relro_start = ph->p_vaddr & -PAGE_SIZE;
1403 p->relro_end = (ph->p_vaddr + ph->p_memsz) & -PAGE_SIZE;
1404 } else if (ph->p_type == PT_GNU_STACK) {
1405 if (!runtime && ph->p_memsz > __default_stacksize) {
1406 __default_stacksize =
1407 ph->p_memsz < DEFAULT_STACK_MAX ?
1408 ph->p_memsz : DEFAULT_STACK_MAX;
1411 if (ph->p_type != PT_LOAD) continue;
1412 if (ph->p_vaddr < min_addr)
1413 min_addr = ph->p_vaddr;
1414 if (ph->p_vaddr+ph->p_memsz > max_addr)
1415 max_addr = ph->p_vaddr+ph->p_memsz;
1417 min_addr &= -PAGE_SIZE;
1418 max_addr = (max_addr + PAGE_SIZE-1) & -PAGE_SIZE;
1419 p->map = p->base + min_addr;
1420 p->map_len = max_addr - min_addr;
1421 p->kernel_mapped = 1;
1424 void __libc_exit_fini()
1427 size_t dyn[DYN_CNT];
1428 pthread_t self = __pthread_self();
1430 /* Take both locks before setting shutting_down, so that
1431 * either lock is sufficient to read its value. The lock
1432 * order matches that in dlopen to avoid deadlock. */
1433 pthread_rwlock_wrlock(&lock);
1434 pthread_mutex_lock(&init_fini_lock);
1436 pthread_rwlock_unlock(&lock);
1437 for (p=fini_head; p; p=p->fini_next) {
1438 while (p->ctor_visitor && p->ctor_visitor!=self)
1439 pthread_cond_wait(&ctor_cond, &init_fini_lock);
1440 if (!p->constructed) continue;
1441 decode_vec(p->dynv, dyn, DYN_CNT);
1442 if (dyn[0] & (1<<DT_FINI_ARRAY)) {
1443 size_t n = dyn[DT_FINI_ARRAYSZ]/sizeof(size_t);
1444 size_t *fn = (size_t *)laddr(p, dyn[DT_FINI_ARRAY])+n;
1445 while (n--) ((void (*)(void))*--fn)();
1447 #ifndef NO_LEGACY_INITFINI
1448 if ((dyn[0] & (1<<DT_FINI)) && dyn[DT_FINI])
1449 fpaddr(p, dyn[DT_FINI])();
1454 void __ldso_atfork(int who)
1457 pthread_rwlock_wrlock(&lock);
1458 pthread_mutex_lock(&init_fini_lock);
1460 pthread_mutex_unlock(&init_fini_lock);
1461 pthread_rwlock_unlock(&lock);
1465 static struct dso **queue_ctors(struct dso *dso)
1467 size_t cnt, qpos, spos, i;
1468 struct dso *p, **queue, **stack;
1470 if (ldd_mode) return 0;
1472 /* Bound on queue size is the total number of indirect deps.
1473 * If a bfs deps list was built, we can use it. Otherwise,
1474 * bound by the total number of DSOs, which is always safe and
1475 * is reasonable we use it (for main app at startup). */
1476 if (dso->bfs_built) {
1477 for (cnt=0; dso->deps[cnt]; cnt++)
1478 dso->deps[cnt]->mark = 0;
1479 cnt++; /* self, not included in deps */
1481 for (cnt=0, p=head; p; cnt++, p=p->next)
1484 cnt++; /* termination slot */
1485 if (dso==head && cnt <= countof(builtin_ctor_queue))
1486 queue = builtin_ctor_queue;
1488 queue = calloc(cnt, sizeof *queue);
1491 error("Error allocating constructor queue: %m\n");
1492 if (runtime) longjmp(*rtld_fail, 1);
1496 /* Opposite ends of the allocated buffer serve as an output queue
1497 * and a working stack. Setup initial stack with just the argument
1498 * dso and initial queue empty... */
1502 stack[--spos] = dso;
1506 /* Then perform pseudo-DFS sort, but ignoring circular deps. */
1509 while (p->next_dep < p->ndeps_direct) {
1510 if (p->deps[p->next_dep]->mark) {
1514 p = p->deps[p->next_dep];
1522 for (i=0; i<qpos; i++) queue[i]->mark = 0;
1523 for (i=0; i<qpos; i++)
1524 if (queue[i]->ctor_visitor && queue[i]->ctor_visitor->tid < 0) {
1525 error("State of %s is inconsistent due to multithreaded fork\n",
1528 if (runtime) longjmp(*rtld_fail, 1);
1534 static void do_init_fini(struct dso **queue)
1537 size_t dyn[DYN_CNT], i;
1538 pthread_t self = __pthread_self();
1540 pthread_mutex_lock(&init_fini_lock);
1541 for (i=0; (p=queue[i]); i++) {
1542 while ((p->ctor_visitor && p->ctor_visitor!=self) || shutting_down)
1543 pthread_cond_wait(&ctor_cond, &init_fini_lock);
1544 if (p->ctor_visitor || p->constructed)
1546 p->ctor_visitor = self;
1548 decode_vec(p->dynv, dyn, DYN_CNT);
1549 if (dyn[0] & ((1<<DT_FINI) | (1<<DT_FINI_ARRAY))) {
1550 p->fini_next = fini_head;
1554 pthread_mutex_unlock(&init_fini_lock);
1556 #ifndef NO_LEGACY_INITFINI
1557 if ((dyn[0] & (1<<DT_INIT)) && dyn[DT_INIT])
1558 fpaddr(p, dyn[DT_INIT])();
1560 if (dyn[0] & (1<<DT_INIT_ARRAY)) {
1561 size_t n = dyn[DT_INIT_ARRAYSZ]/sizeof(size_t);
1562 size_t *fn = laddr(p, dyn[DT_INIT_ARRAY]);
1563 while (n--) ((void (*)(void))*fn++)();
1566 pthread_mutex_lock(&init_fini_lock);
1567 p->ctor_visitor = 0;
1569 pthread_cond_broadcast(&ctor_cond);
1571 pthread_mutex_unlock(&init_fini_lock);
1574 void __libc_start_init(void)
1576 do_init_fini(main_ctor_queue);
1577 if (!__malloc_replaced && main_ctor_queue != builtin_ctor_queue)
1578 free(main_ctor_queue);
1579 main_ctor_queue = 0;
1582 static void dl_debug_state(void)
1586 weak_alias(dl_debug_state, _dl_debug_state);
1588 void __init_tls(size_t *auxv)
1592 static void update_tls_size()
1594 libc.tls_cnt = tls_cnt;
1595 libc.tls_align = tls_align;
1596 libc.tls_size = ALIGN(
1597 (1+tls_cnt) * sizeof(void *) +
1599 sizeof(struct pthread) +
1604 static void install_new_tls(void)
1607 pthread_t self = __pthread_self(), td;
1608 struct dso *dtv_provider = container_of(tls_tail, struct dso, tls);
1609 uintptr_t (*newdtv)[tls_cnt+1] = (void *)dtv_provider->new_dtv;
1612 size_t old_cnt = self->dtv[0];
1614 __block_app_sigs(&set);
1616 /* Copy existing dtv contents from all existing threads. */
1617 for (i=0, td=self; !i || td!=self; i++, td=td->next) {
1618 memcpy(newdtv+i, td->dtv,
1619 (old_cnt+1)*sizeof(uintptr_t));
1620 newdtv[i][0] = tls_cnt;
1622 /* Install new dtls into the enlarged, uninstalled dtv copies. */
1623 for (p=head; ; p=p->next) {
1624 if (p->tls_id <= old_cnt) continue;
1625 unsigned char *mem = p->new_tls;
1626 for (j=0; j<i; j++) {
1627 unsigned char *new = mem;
1628 new += ((uintptr_t)p->tls.image - (uintptr_t)mem)
1630 memcpy(new, p->tls.image, p->tls.len);
1631 newdtv[j][p->tls_id] =
1632 (uintptr_t)new + DTP_OFFSET;
1633 mem += p->tls.size + p->tls.align;
1635 if (p->tls_id == tls_cnt) break;
1638 /* Broadcast barrier to ensure contents of new dtv is visible
1639 * if the new dtv pointer is. The __membarrier function has a
1640 * fallback emulation using signals for kernels that lack the
1641 * feature at the syscall level. */
1643 __membarrier(MEMBARRIER_CMD_PRIVATE_EXPEDITED, 0);
1645 /* Install new dtv for each thread. */
1646 for (j=0, td=self; !j || td!=self; j++, td=td->next) {
1647 td->dtv = newdtv[j];
1651 __restore_sigs(&set);
1654 /* Stage 1 of the dynamic linker is defined in dlstart.c. It calls the
1655 * following stage 2 and stage 3 functions via primitive symbolic lookup
1656 * since it does not have access to their addresses to begin with. */
1658 /* Stage 2 of the dynamic linker is called after relative relocations
1659 * have been processed. It can make function calls to static functions
1660 * and access string literals and static data, but cannot use extern
1661 * symbols. Its job is to perform symbolic relocations on the dynamic
1662 * linker itself, but some of the relocations performed may need to be
1663 * replaced later due to copy relocations in the main program. */
1665 hidden void __dls2(unsigned char *base, size_t *sp)
1668 for (auxv=sp+1+*sp+1; *auxv; auxv++);
1671 void *p1 = (void *)sp[-2];
1672 void *p2 = (void *)sp[-1];
1674 size_t aux[AUX_CNT];
1675 decode_vec(auxv, aux, AUX_CNT);
1676 if (aux[AT_BASE]) ldso.base = (void *)aux[AT_BASE];
1677 else ldso.base = (void *)(aux[AT_PHDR] & -4096);
1679 app_loadmap = p2 ? p1 : 0;
1680 ldso.loadmap = p2 ? p2 : p1;
1681 ldso.base = laddr(&ldso, 0);
1685 Ehdr *ehdr = (void *)ldso.base;
1686 ldso.name = ldso.shortname = "libc.so";
1687 ldso.phnum = ehdr->e_phnum;
1688 ldso.phdr = laddr(&ldso, ehdr->e_phoff);
1689 ldso.phentsize = ehdr->e_phentsize;
1690 kernel_mapped_dso(&ldso);
1693 if (DL_FDPIC) makefuncdescs(&ldso);
1695 /* Prepare storage for to save clobbered REL addends so they
1696 * can be reused in stage 3. There should be very few. If
1697 * something goes wrong and there are a huge number, abort
1698 * instead of risking stack overflow. */
1699 size_t dyn[DYN_CNT];
1700 decode_vec(ldso.dynv, dyn, DYN_CNT);
1701 size_t *rel = laddr(&ldso, dyn[DT_REL]);
1702 size_t rel_size = dyn[DT_RELSZ];
1703 size_t symbolic_rel_cnt = 0;
1704 apply_addends_to = rel;
1705 for (; rel_size; rel+=2, rel_size-=2*sizeof(size_t))
1706 if (!IS_RELATIVE(rel[1], ldso.syms)) symbolic_rel_cnt++;
1707 if (symbolic_rel_cnt >= ADDEND_LIMIT) a_crash();
1708 size_t addends[symbolic_rel_cnt+1];
1709 saved_addends = addends;
1716 /* Call dynamic linker stage-2b, __dls2b, looking it up
1717 * symbolically as a barrier against moving the address
1718 * load across the above relocation processing. */
1719 struct symdef dls2b_def = find_sym(&ldso, "__dls2b", 0);
1720 if (DL_FDPIC) ((stage3_func)&ldso.funcdescs[dls2b_def.sym-ldso.syms])(sp, auxv);
1721 else ((stage3_func)laddr(&ldso, dls2b_def.sym->st_value))(sp, auxv);
1724 /* Stage 2b sets up a valid thread pointer, which requires relocations
1725 * completed in stage 2, and on which stage 3 is permitted to depend.
1726 * This is done as a separate stage, with symbolic lookup as a barrier,
1727 * so that loads of the thread pointer and &errno can be pure/const and
1728 * thereby hoistable. */
1730 void __dls2b(size_t *sp, size_t *auxv)
1732 /* Setup early thread pointer in builtin_tls for ldso/libc itself to
1733 * use during dynamic linking. If possible it will also serve as the
1734 * thread pointer at runtime. */
1735 search_vec(auxv, &__hwcap, AT_HWCAP);
1737 libc.tls_size = sizeof builtin_tls;
1738 libc.tls_align = tls_align;
1739 if (__init_tp(__copy_tls((void *)builtin_tls)) < 0) {
1743 struct symdef dls3_def = find_sym(&ldso, "__dls3", 0);
1744 if (DL_FDPIC) ((stage3_func)&ldso.funcdescs[dls3_def.sym-ldso.syms])(sp, auxv);
1745 else ((stage3_func)laddr(&ldso, dls3_def.sym->st_value))(sp, auxv);
1748 /* Stage 3 of the dynamic linker is called with the dynamic linker/libc
1749 * fully functional. Its job is to load (if not already loaded) and
1750 * process dependencies and relocations for the main application and
1751 * transfer control to its entry point. */
1753 void __dls3(size_t *sp, size_t *auxv)
1755 static struct dso app, vdso;
1756 size_t aux[AUX_CNT];
1758 char *env_preload=0;
1759 char *replace_argv0=0;
1762 char **argv = (void *)(sp+1);
1763 char **argv_orig = argv;
1764 char **envp = argv+argc+1;
1766 /* Find aux vector just past environ[] and use it to initialize
1767 * global data that may be needed before we can make syscalls. */
1769 decode_vec(auxv, aux, AUX_CNT);
1770 search_vec(auxv, &__sysinfo, AT_SYSINFO);
1771 __pthread_self()->sysinfo = __sysinfo;
1772 libc.page_size = aux[AT_PAGESZ];
1773 libc.secure = ((aux[0]&0x7800)!=0x7800 || aux[AT_UID]!=aux[AT_EUID]
1774 || aux[AT_GID]!=aux[AT_EGID] || aux[AT_SECURE]);
1776 /* Only trust user/env if kernel says we're not suid/sgid */
1778 env_path = getenv("LD_LIBRARY_PATH");
1779 env_preload = getenv("LD_PRELOAD");
1782 /* Activate error handler function */
1785 /* If the main program was already loaded by the kernel,
1786 * AT_PHDR will point to some location other than the dynamic
1787 * linker's program headers. */
1788 if (aux[AT_PHDR] != (size_t)ldso.phdr) {
1789 size_t interp_off = 0;
1790 size_t tls_image = 0;
1791 /* Find load address of the main program, via AT_PHDR vs PT_PHDR. */
1792 Phdr *phdr = app.phdr = (void *)aux[AT_PHDR];
1793 app.phnum = aux[AT_PHNUM];
1794 app.phentsize = aux[AT_PHENT];
1795 for (i=aux[AT_PHNUM]; i; i--, phdr=(void *)((char *)phdr + aux[AT_PHENT])) {
1796 if (phdr->p_type == PT_PHDR)
1797 app.base = (void *)(aux[AT_PHDR] - phdr->p_vaddr);
1798 else if (phdr->p_type == PT_INTERP)
1799 interp_off = (size_t)phdr->p_vaddr;
1800 else if (phdr->p_type == PT_TLS) {
1801 tls_image = phdr->p_vaddr;
1802 app.tls.len = phdr->p_filesz;
1803 app.tls.size = phdr->p_memsz;
1804 app.tls.align = phdr->p_align;
1807 if (DL_FDPIC) app.loadmap = app_loadmap;
1808 if (app.tls.size) app.tls.image = laddr(&app, tls_image);
1809 if (interp_off) ldso.name = laddr(&app, interp_off);
1810 if ((aux[0] & (1UL<<AT_EXECFN))
1811 && strncmp((char *)aux[AT_EXECFN], "/proc/", 6))
1812 app.name = (char *)aux[AT_EXECFN];
1815 kernel_mapped_dso(&app);
1818 char *ldname = argv[0];
1819 size_t l = strlen(ldname);
1820 if (l >= 3 && !strcmp(ldname+l-3, "ldd")) ldd_mode = 1;
1822 while (argv[0] && argv[0][0]=='-' && argv[0][1]=='-') {
1823 char *opt = argv[0]+2;
1824 *argv++ = (void *)-1;
1827 } else if (!memcmp(opt, "list", 5)) {
1829 } else if (!memcmp(opt, "library-path", 12)) {
1830 if (opt[12]=='=') env_path = opt+13;
1831 else if (opt[12]) *argv = 0;
1832 else if (*argv) env_path = *argv++;
1833 } else if (!memcmp(opt, "preload", 7)) {
1834 if (opt[7]=='=') env_preload = opt+8;
1835 else if (opt[7]) *argv = 0;
1836 else if (*argv) env_preload = *argv++;
1837 } else if (!memcmp(opt, "argv0", 5)) {
1838 if (opt[5]=='=') replace_argv0 = opt+6;
1839 else if (opt[5]) *argv = 0;
1840 else if (*argv) replace_argv0 = *argv++;
1845 argv[-1] = (void *)(argc - (argv-argv_orig));
1847 dprintf(2, "musl libc (" LDSO_ARCH ")\n"
1849 "Dynamic Program Loader\n"
1850 "Usage: %s [options] [--] pathname%s\n",
1851 __libc_version, ldname,
1852 ldd_mode ? "" : " [args]");
1855 fd = open(argv[0], O_RDONLY);
1857 dprintf(2, "%s: cannot load %s: %s\n", ldname, argv[0], strerror(errno));
1860 Ehdr *ehdr = map_library(fd, &app);
1862 dprintf(2, "%s: %s: Not a valid dynamic program\n", ldname, argv[0]);
1868 aux[AT_ENTRY] = (size_t)laddr(&app, ehdr->e_entry);
1869 /* Find the name that would have been used for the dynamic
1870 * linker had ldd not taken its place. */
1872 for (i=0; i<app.phnum; i++) {
1873 if (app.phdr[i].p_type == PT_INTERP)
1874 ldso.name = laddr(&app, app.phdr[i].p_vaddr);
1876 dprintf(1, "\t%s (%p)\n", ldso.name, ldso.base);
1880 libc.tls_head = tls_tail = &app.tls;
1881 app.tls_id = tls_cnt = 1;
1883 app.tls.offset = GAP_ABOVE_TP;
1884 app.tls.offset += (-GAP_ABOVE_TP + (uintptr_t)app.tls.image)
1885 & (app.tls.align-1);
1886 tls_offset = app.tls.offset + app.tls.size;
1888 tls_offset = app.tls.offset = app.tls.size
1889 + ( -((uintptr_t)app.tls.image + app.tls.size)
1890 & (app.tls.align-1) );
1892 tls_align = MAXP2(tls_align, app.tls.align);
1896 makefuncdescs(&app);
1898 app.loadmap = (void *)&app_dummy_loadmap;
1899 app.loadmap->nsegs = 1;
1900 app.loadmap->segs[0].addr = (size_t)app.map;
1901 app.loadmap->segs[0].p_vaddr = (size_t)app.map
1903 app.loadmap->segs[0].p_memsz = app.map_len;
1905 argv[-3] = (void *)app.loadmap;
1908 /* Initial dso chain consists only of the app. */
1909 head = tail = syms_tail = &app;
1911 /* Donate unused parts of app and library mapping to malloc */
1913 reclaim_gaps(&ldso);
1915 /* Load preload/needed libraries, add symbols to global namespace. */
1916 ldso.deps = (struct dso **)no_deps;
1917 if (env_preload) load_preload(env_preload);
1919 for (struct dso *p=head; p; p=p->next)
1922 /* Attach to vdso, if provided by the kernel, last so that it does
1923 * not become part of the global namespace. */
1924 if (search_vec(auxv, &vdso_base, AT_SYSINFO_EHDR) && vdso_base) {
1925 Ehdr *ehdr = (void *)vdso_base;
1926 Phdr *phdr = vdso.phdr = (void *)(vdso_base + ehdr->e_phoff);
1927 vdso.phnum = ehdr->e_phnum;
1928 vdso.phentsize = ehdr->e_phentsize;
1929 for (i=ehdr->e_phnum; i; i--, phdr=(void *)((char *)phdr + ehdr->e_phentsize)) {
1930 if (phdr->p_type == PT_DYNAMIC)
1931 vdso.dynv = (void *)(vdso_base + phdr->p_offset);
1932 if (phdr->p_type == PT_LOAD)
1933 vdso.base = (void *)(vdso_base - phdr->p_vaddr + phdr->p_offset);
1936 vdso.shortname = "linux-gate.so.1";
1938 vdso.deps = (struct dso **)no_deps;
1945 for (i=0; app.dynv[i]; i+=2) {
1946 if (!DT_DEBUG_INDIRECT && app.dynv[i]==DT_DEBUG)
1947 app.dynv[i+1] = (size_t)&debug;
1948 if (DT_DEBUG_INDIRECT && app.dynv[i]==DT_DEBUG_INDIRECT) {
1949 size_t *ptr = (size_t *) app.dynv[i+1];
1950 *ptr = (size_t)&debug;
1954 /* This must be done before final relocations, since it calls
1955 * malloc, which may be provided by the application. Calling any
1956 * application code prior to the jump to its entry point is not
1957 * valid in our model and does not work with FDPIC, where there
1958 * are additional relocation-like fixups that only the entry point
1959 * code can see to perform. */
1960 main_ctor_queue = queue_ctors(&app);
1962 /* Initial TLS must also be allocated before final relocations
1963 * might result in calloc being a call to application code. */
1965 void *initial_tls = builtin_tls;
1966 if (libc.tls_size > sizeof builtin_tls || tls_align > MIN_TLS_ALIGN) {
1967 initial_tls = calloc(libc.tls_size, 1);
1969 dprintf(2, "%s: Error getting %zu bytes thread-local storage: %m\n",
1970 argv[0], libc.tls_size);
1974 static_tls_cnt = tls_cnt;
1976 /* The main program must be relocated LAST since it may contain
1977 * copy relocations which depend on libraries' relocations. */
1978 reloc_all(app.next);
1981 /* Actual copying to new TLS needs to happen after relocations,
1982 * since the TLS images might have contained relocated addresses. */
1983 if (initial_tls != builtin_tls) {
1984 if (__init_tp(__copy_tls(initial_tls)) < 0) {
1988 size_t tmp_tls_size = libc.tls_size;
1989 pthread_t self = __pthread_self();
1990 /* Temporarily set the tls size to the full size of
1991 * builtin_tls so that __copy_tls will use the same layout
1992 * as it did for before. Then check, just to be safe. */
1993 libc.tls_size = sizeof builtin_tls;
1994 if (__copy_tls((void*)builtin_tls) != self) a_crash();
1995 libc.tls_size = tmp_tls_size;
1998 if (ldso_fail) _exit(127);
1999 if (ldd_mode) _exit(0);
2001 /* Determine if malloc was interposed by a replacement implementation
2002 * so that calloc and the memalign family can harden against the
2003 * possibility of incomplete replacement. */
2004 if (find_sym(head, "malloc", 1).dso != &ldso)
2005 __malloc_replaced = 1;
2006 if (find_sym(head, "aligned_alloc", 1).dso != &ldso)
2007 __aligned_alloc_replaced = 1;
2009 /* Switch to runtime mode: any further failures in the dynamic
2010 * linker are a reportable failure rather than a fatal startup
2015 debug.bp = dl_debug_state;
2017 debug.base = ldso.base;
2018 debug.state = RT_CONSISTENT;
2021 if (replace_argv0) argv[0] = replace_argv0;
2025 CRTJMP((void *)aux[AT_ENTRY], argv-1);
2029 static void prepare_lazy(struct dso *p)
2031 size_t dyn[DYN_CNT], n, flags1=0;
2032 decode_vec(p->dynv, dyn, DYN_CNT);
2033 search_vec(p->dynv, &flags1, DT_FLAGS_1);
2034 if (dyn[DT_BIND_NOW] || (dyn[DT_FLAGS] & DF_BIND_NOW) || (flags1 & DF_1_NOW))
2036 n = dyn[DT_RELSZ]/2 + dyn[DT_RELASZ]/3 + dyn[DT_PLTRELSZ]/2 + 1;
2037 if (NEED_MIPS_GOT_RELOCS) {
2038 size_t j=0; search_vec(p->dynv, &j, DT_MIPS_GOTSYM);
2039 size_t i=0; search_vec(p->dynv, &i, DT_MIPS_SYMTABNO);
2042 p->lazy = calloc(n, 3*sizeof(size_t));
2044 error("Error preparing lazy relocation for %s: %m", p->name);
2045 longjmp(*rtld_fail, 1);
2047 p->lazy_next = lazy_head;
2051 void *dlopen(const char *file, int mode)
2053 struct dso *volatile p, *orig_tail, *orig_syms_tail, *orig_lazy_head, *next;
2054 struct tls_module *orig_tls_tail;
2055 size_t orig_tls_cnt, orig_tls_offset, orig_tls_align;
2059 struct dso **volatile ctor_queue = 0;
2061 if (!file) return head;
2063 pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
2064 pthread_rwlock_wrlock(&lock);
2067 debug.state = RT_ADD;
2071 if (shutting_down) {
2072 error("Cannot dlopen while program is exiting.");
2075 orig_tls_tail = tls_tail;
2076 orig_tls_cnt = tls_cnt;
2077 orig_tls_offset = tls_offset;
2078 orig_tls_align = tls_align;
2079 orig_lazy_head = lazy_head;
2080 orig_syms_tail = syms_tail;
2082 noload = mode & RTLD_NOLOAD;
2085 if (setjmp(*rtld_fail)) {
2086 /* Clean up anything new that was (partially) loaded */
2087 revert_syms(orig_syms_tail);
2088 for (p=orig_tail->next; p; p=next) {
2090 while (p->td_index) {
2091 void *tmp = p->td_index->next;
2096 if (p->rpath != p->rpath_orig)
2104 if (!orig_tls_tail) libc.tls_head = 0;
2105 tls_tail = orig_tls_tail;
2106 if (tls_tail) tls_tail->next = 0;
2107 tls_cnt = orig_tls_cnt;
2108 tls_offset = orig_tls_offset;
2109 tls_align = orig_tls_align;
2110 lazy_head = orig_lazy_head;
2115 } else p = load_library(file, head);
2119 "Library %s is not already loaded" :
2120 "Error loading shared library %s: %m",
2125 /* First load handling */
2128 pthread_mutex_lock(&init_fini_lock);
2129 int constructed = p->constructed;
2130 pthread_mutex_unlock(&init_fini_lock);
2131 if (!constructed) ctor_queue = queue_ctors(p);
2132 if (!p->relocated && (mode & RTLD_LAZY)) {
2134 for (i=0; p->deps[i]; i++)
2135 if (!p->deps[i]->relocated)
2136 prepare_lazy(p->deps[i]);
2138 if (!p->relocated || (mode & RTLD_GLOBAL)) {
2139 /* Make new symbols global, at least temporarily, so we can do
2140 * relocations. If not RTLD_GLOBAL, this is reverted below. */
2142 for (i=0; p->deps[i]; i++)
2143 add_syms(p->deps[i]);
2145 if (!p->relocated) {
2149 /* If RTLD_GLOBAL was not specified, undo any new additions
2150 * to the global symbol table. This is a nop if the library was
2151 * previously loaded and already global. */
2152 if (!(mode & RTLD_GLOBAL))
2153 revert_syms(orig_syms_tail);
2155 /* Processing of deferred lazy relocations must not happen until
2156 * the new libraries are committed; otherwise we could end up with
2157 * relocations resolved to symbol definitions that get removed. */
2161 if (tls_cnt != orig_tls_cnt)
2165 debug.state = RT_CONSISTENT;
2169 pthread_rwlock_unlock(&lock);
2171 do_init_fini(ctor_queue);
2174 pthread_setcancelstate(cs, 0);
2178 hidden int __dl_invalid_handle(void *h)
2181 for (p=head; p; p=p->next) if (h==p) return 0;
2182 error("Invalid library handle %p", (void *)h);
2186 static void *addr2dso(size_t a)
2190 if (DL_FDPIC) for (p=head; p; p=p->next) {
2192 if (a-(size_t)p->funcdescs < i*sizeof(*p->funcdescs))
2195 for (p=head; p; p=p->next) {
2196 if (DL_FDPIC && p->loadmap) {
2197 for (i=0; i<p->loadmap->nsegs; i++) {
2198 if (a-p->loadmap->segs[i].p_vaddr
2199 < p->loadmap->segs[i].p_memsz)
2204 size_t phcnt = p->phnum;
2205 size_t entsz = p->phentsize;
2206 size_t base = (size_t)p->base;
2207 for (; phcnt--; ph=(void *)((char *)ph+entsz)) {
2208 if (ph->p_type != PT_LOAD) continue;
2209 if (a-base-ph->p_vaddr < ph->p_memsz)
2212 if (a-(size_t)p->map < p->map_len)
2219 static void *do_dlsym(struct dso *p, const char *s, void *ra)
2222 if (p == head || p == RTLD_DEFAULT) {
2224 } else if (p == RTLD_NEXT) {
2225 p = addr2dso((size_t)ra);
2228 } else if (__dl_invalid_handle(p)) {
2232 struct symdef def = find_sym2(p, s, 0, use_deps);
2234 error("Symbol not found: %s", s);
2237 if ((def.sym->st_info&0xf) == STT_TLS)
2238 return __tls_get_addr((tls_mod_off_t []){def.dso->tls_id, def.sym->st_value-DTP_OFFSET});
2239 if (DL_FDPIC && (def.sym->st_info&0xf) == STT_FUNC)
2240 return def.dso->funcdescs + (def.sym - def.dso->syms);
2241 return laddr(def.dso, def.sym->st_value);
2244 int dladdr(const void *addr_arg, Dl_info *info)
2246 size_t addr = (size_t)addr_arg;
2252 size_t besterr = -1;
2254 pthread_rwlock_rdlock(&lock);
2256 pthread_rwlock_unlock(&lock);
2261 strings = p->strings;
2262 nsym = count_syms(p);
2265 size_t idx = (addr-(size_t)p->funcdescs)
2266 / sizeof(*p->funcdescs);
2267 if (idx < nsym && (sym[idx].st_info&0xf) == STT_FUNC) {
2268 best = (size_t)(p->funcdescs + idx);
2269 bestsym = sym + idx;
2274 if (!best) for (; nsym; nsym--, sym++) {
2276 && (1<<(sym->st_info&0xf) & OK_TYPES)
2277 && (1<<(sym->st_info>>4) & OK_BINDS)) {
2278 size_t symaddr = (size_t)laddr(p, sym->st_value);
2279 if (symaddr > addr || symaddr <= best)
2283 besterr = addr - symaddr;
2284 if (addr == symaddr)
2289 if (best && besterr > bestsym->st_size-1) {
2294 info->dli_fname = p->name;
2295 info->dli_fbase = p->map;
2298 info->dli_sname = 0;
2299 info->dli_saddr = 0;
2303 if (DL_FDPIC && (bestsym->st_info&0xf) == STT_FUNC)
2304 best = (size_t)(p->funcdescs + (bestsym - p->syms));
2305 info->dli_sname = strings + bestsym->st_name;
2306 info->dli_saddr = (void *)best;
2311 hidden void *__dlsym(void *restrict p, const char *restrict s, void *restrict ra)
2314 pthread_rwlock_rdlock(&lock);
2315 res = do_dlsym(p, s, ra);
2316 pthread_rwlock_unlock(&lock);
2320 hidden void *__dlsym_redir_time64(void *restrict p, const char *restrict s, void *restrict ra)
2323 const char *suffix, *suffix2 = "";
2326 /* Map the symbol name to a time64 version of itself according to the
2327 * pattern used for naming the redirected time64 symbols. */
2328 size_t l = strnlen(s, sizeof redir);
2329 if (l<4 || l==sizeof redir) goto no_redir;
2330 if (s[l-2]=='_' && s[l-1]=='r') {
2334 if (l<4) goto no_redir;
2335 if (!strcmp(s+l-4, "time")) suffix = "64";
2336 else suffix = "_time64";
2338 /* Use the presence of the remapped symbol name in libc to determine
2339 * whether it's one that requires time64 redirection; replace if so. */
2340 snprintf(redir, sizeof redir, "__%.*s%s%s", (int)l, s, suffix, suffix2);
2341 if (find_sym(&ldso, redir, 1).sym) s = redir;
2344 return __dlsym(p, s, ra);
2347 int dl_iterate_phdr(int(*callback)(struct dl_phdr_info *info, size_t size, void *data), void *data)
2349 struct dso *current;
2350 struct dl_phdr_info info;
2352 for(current = head; current;) {
2353 info.dlpi_addr = (uintptr_t)current->base;
2354 info.dlpi_name = current->name;
2355 info.dlpi_phdr = current->phdr;
2356 info.dlpi_phnum = current->phnum;
2357 info.dlpi_adds = gencnt;
2359 info.dlpi_tls_modid = current->tls_id;
2360 info.dlpi_tls_data = !current->tls_id ? 0 :
2361 __tls_get_addr((tls_mod_off_t[]){current->tls_id,0});
2363 ret = (callback)(&info, sizeof (info), data);
2365 if (ret != 0) break;
2367 pthread_rwlock_rdlock(&lock);
2368 current = current->next;
2369 pthread_rwlock_unlock(&lock);
2374 static void error_impl(const char *fmt, ...)
2379 vdprintf(2, fmt, ap);
2385 __dl_vseterr(fmt, ap);
2389 static void error_noop(const char *fmt, ...)