20 #include <semaphore.h>
21 #include "pthread_impl.h"
24 #include "malloc_impl.h"
26 static void error(const char *, ...);
28 #define MAXP2(a,b) (-(-(a)&-(b)))
29 #define ALIGN(x,y) ((x)+(y)-1 & -(y))
41 struct td_index
*next
;
46 struct fdpic_loadmap
*loadmap
;
52 struct dso
*next
, *prev
;
62 struct dso
*syms_next
, *lazy_next
;
63 size_t *lazy
, lazy_cnt
;
71 struct dso
**deps
, *needed_by
;
72 char *rpath_orig
, *rpath
;
73 struct tls_module tls
;
75 size_t relro_start
, relro_end
;
77 unsigned char *new_tls
;
78 volatile int new_dtv_idx
, new_tls_idx
;
79 struct td_index
*td_index
;
80 struct dso
*fini_next
;
85 struct fdpic_loadmap
*loadmap
;
100 static struct builtin_tls
{
105 #define MIN_TLS_ALIGN offsetof(struct builtin_tls, pt)
107 #define ADDEND_LIMIT 4096
108 static size_t *saved_addends
, *apply_addends_to
;
110 static struct dso ldso
;
111 static struct dso
*head
, *tail
, *fini_head
, *syms_tail
, *lazy_head
;
112 static char *env_path
, *sys_path
;
113 static unsigned long long gencnt
;
116 static int ldso_fail
;
118 static jmp_buf *rtld_fail
;
119 static pthread_rwlock_t lock
;
120 static struct debug debug
;
121 static struct tls_module
*tls_tail
;
122 static size_t tls_cnt
, tls_offset
, tls_align
= MIN_TLS_ALIGN
;
123 static size_t static_tls_cnt
;
124 static pthread_mutex_t init_fini_lock
= { ._m_type
= PTHREAD_MUTEX_RECURSIVE
};
125 static struct fdpic_loadmap
*app_loadmap
;
126 static struct fdpic_dummy_loadmap app_dummy_loadmap
;
127 static struct dso
*const nodeps_dummy
;
129 struct debug
*_dl_debug_addr
= &debug
;
131 extern hidden
int __malloc_replaced
;
133 hidden
void (*const __init_array_start
)(void)=0, (*const __fini_array_start
)(void)=0;
135 extern hidden
void (*const __init_array_end
)(void), (*const __fini_array_end
)(void);
137 weak_alias(__init_array_start
, __init_array_end
);
138 weak_alias(__fini_array_start
, __fini_array_end
);
140 static int dl_strcmp(const char *l
, const char *r
)
142 for (; *l
==*r
&& *l
; l
++, r
++);
143 return *(unsigned char *)l
- *(unsigned char *)r
;
145 #define strcmp(l,r) dl_strcmp(l,r)
147 /* Compute load address for a virtual address in a given dso. */
149 static void *laddr(const struct dso
*p
, size_t v
)
152 if (!p
->loadmap
) return p
->base
+ v
;
153 for (j
=0; v
-p
->loadmap
->segs
[j
].p_vaddr
>= p
->loadmap
->segs
[j
].p_memsz
; j
++);
154 return (void *)(v
- p
->loadmap
->segs
[j
].p_vaddr
+ p
->loadmap
->segs
[j
].addr
);
156 static void *laddr_pg(const struct dso
*p
, size_t v
)
159 size_t pgsz
= PAGE_SIZE
;
160 if (!p
->loadmap
) return p
->base
+ v
;
162 size_t a
= p
->loadmap
->segs
[j
].p_vaddr
;
163 size_t b
= a
+ p
->loadmap
->segs
[j
].p_memsz
;
169 return (void *)(v
- p
->loadmap
->segs
[j
].p_vaddr
+ p
->loadmap
->segs
[j
].addr
);
171 #define fpaddr(p, v) ((void (*)())&(struct funcdesc){ \
172 laddr(p, v), (p)->got })
174 #define laddr(p, v) (void *)((p)->base + (v))
175 #define laddr_pg(p, v) laddr(p, v)
176 #define fpaddr(p, v) ((void (*)())laddr(p, v))
179 static void decode_vec(size_t *v
, size_t *a
, size_t cnt
)
182 for (i
=0; i
<cnt
; i
++) a
[i
] = 0;
183 for (; v
[0]; v
+=2) if (v
[0]-1<cnt
-1) {
189 static int search_vec(size_t *v
, size_t *r
, size_t key
)
191 for (; v
[0]!=key
; v
+=2)
197 static uint32_t sysv_hash(const char *s0
)
199 const unsigned char *s
= (void *)s0
;
205 return h
& 0xfffffff;
208 static uint32_t gnu_hash(const char *s0
)
210 const unsigned char *s
= (void *)s0
;
211 uint_fast32_t h
= 5381;
217 static Sym
*sysv_lookup(const char *s
, uint32_t h
, struct dso
*dso
)
220 Sym
*syms
= dso
->syms
;
221 Elf_Symndx
*hashtab
= dso
->hashtab
;
222 char *strings
= dso
->strings
;
223 for (i
=hashtab
[2+h
%hashtab
[0]]; i
; i
=hashtab
[2+hashtab
[0]+i
]) {
224 if ((!dso
->versym
|| dso
->versym
[i
] >= 0)
225 && (!strcmp(s
, strings
+syms
[i
].st_name
)))
231 static Sym
*gnu_lookup(uint32_t h1
, uint32_t *hashtab
, struct dso
*dso
, const char *s
)
233 uint32_t nbuckets
= hashtab
[0];
234 uint32_t *buckets
= hashtab
+ 4 + hashtab
[2]*(sizeof(size_t)/4);
235 uint32_t i
= buckets
[h1
% nbuckets
];
239 uint32_t *hashval
= buckets
+ nbuckets
+ (i
- hashtab
[1]);
241 for (h1
|= 1; ; i
++) {
242 uint32_t h2
= *hashval
++;
243 if ((h1
== (h2
|1)) && (!dso
->versym
|| dso
->versym
[i
] >= 0)
244 && !strcmp(s
, dso
->strings
+ dso
->syms
[i
].st_name
))
252 static Sym
*gnu_lookup_filtered(uint32_t h1
, uint32_t *hashtab
, struct dso
*dso
, const char *s
, uint32_t fofs
, size_t fmask
)
254 const size_t *bloomwords
= (const void *)(hashtab
+4);
255 size_t f
= bloomwords
[fofs
& (hashtab
[2]-1)];
256 if (!(f
& fmask
)) return 0;
258 f
>>= (h1
>> hashtab
[3]) % (8 * sizeof f
);
259 if (!(f
& 1)) return 0;
261 return gnu_lookup(h1
, hashtab
, dso
, s
);
264 #define OK_TYPES (1<<STT_NOTYPE | 1<<STT_OBJECT | 1<<STT_FUNC | 1<<STT_COMMON | 1<<STT_TLS)
265 #define OK_BINDS (1<<STB_GLOBAL | 1<<STB_WEAK | 1<<STB_GNU_UNIQUE)
267 #ifndef ARCH_SYM_REJECT_UND
268 #define ARCH_SYM_REJECT_UND(s) 0
271 static struct symdef
find_sym(struct dso
*dso
, const char *s
, int need_def
)
273 uint32_t h
= 0, gh
= gnu_hash(s
), gho
= gh
/ (8*sizeof(size_t)), *ght
;
274 size_t ghm
= 1ul << gh
% (8*sizeof(size_t));
275 struct symdef def
= {0};
276 for (; dso
; dso
=dso
->syms_next
) {
278 if ((ght
= dso
->ghashtab
)) {
279 sym
= gnu_lookup_filtered(gh
, ght
, dso
, s
, gho
, ghm
);
281 if (!h
) h
= sysv_hash(s
);
282 sym
= sysv_lookup(s
, h
, dso
);
286 if (need_def
|| (sym
->st_info
&0xf) == STT_TLS
287 || ARCH_SYM_REJECT_UND(sym
))
290 if ((sym
->st_info
&0xf) != STT_TLS
)
292 if (!(1<<(sym
->st_info
&0xf) & OK_TYPES
)) continue;
293 if (!(1<<(sym
->st_info
>>4) & OK_BINDS
)) continue;
301 static void do_relocs(struct dso
*dso
, size_t *rel
, size_t rel_size
, size_t stride
)
303 unsigned char *base
= dso
->base
;
304 Sym
*syms
= dso
->syms
;
305 char *strings
= dso
->strings
;
316 int skip_relative
= 0, reuse_addends
= 0, save_slot
= 0;
319 /* Only ldso's REL table needs addend saving/reuse. */
320 if (rel
== apply_addends_to
)
325 for (; rel_size
; rel
+=stride
, rel_size
-=stride
*sizeof(size_t)) {
326 if (skip_relative
&& IS_RELATIVE(rel
[1], dso
->syms
)) continue;
327 type
= R_TYPE(rel
[1]);
328 if (type
== REL_NONE
) continue;
329 reloc_addr
= laddr(dso
, rel
[0]);
333 } else if (type
==REL_GOT
|| type
==REL_PLT
|| type
==REL_COPY
) {
335 } else if (reuse_addends
) {
336 /* Save original addend in stage 2 where the dso
337 * chain consists of just ldso; otherwise read back
338 * saved addend since the inline one was clobbered. */
340 saved_addends
[save_slot
] = *reloc_addr
;
341 addend
= saved_addends
[save_slot
++];
343 addend
= *reloc_addr
;
346 sym_index
= R_SYM(rel
[1]);
348 sym
= syms
+ sym_index
;
349 name
= strings
+ sym
->st_name
;
350 ctx
= type
==REL_COPY
? head
->syms_next
: head
;
351 def
= (sym
->st_info
&0xf) == STT_SECTION
352 ? (struct symdef
){ .dso
= dso
, .sym
= sym
}
353 : find_sym(ctx
, name
, type
==REL_PLT
);
354 if (!def
.sym
&& (sym
->st_shndx
!= SHN_UNDEF
355 || sym
->st_info
>>4 != STB_WEAK
)) {
356 if (dso
->lazy
&& (type
==REL_PLT
|| type
==REL_GOT
)) {
357 dso
->lazy
[3*dso
->lazy_cnt
+0] = rel
[0];
358 dso
->lazy
[3*dso
->lazy_cnt
+1] = rel
[1];
359 dso
->lazy
[3*dso
->lazy_cnt
+2] = addend
;
363 error("Error relocating %s: %s: symbol not found",
365 if (runtime
) longjmp(*rtld_fail
, 1);
374 sym_val
= def
.sym
? (size_t)laddr(def
.dso
, def
.sym
->st_value
) : 0;
375 tls_val
= def
.sym
? def
.sym
->st_value
: 0;
377 if ((type
== REL_TPOFF
|| type
== REL_TPOFF_NEG
)
378 && runtime
&& def
.dso
->tls_id
> static_tls_cnt
) {
379 error("Error relocating %s: %s: initial-exec TLS "
380 "resolves to dynamic definition in %s",
381 dso
->name
, name
, def
.dso
->name
);
382 longjmp(*rtld_fail
, 1);
389 addend
-= (size_t)reloc_addr
;
393 *reloc_addr
= sym_val
+ addend
;
396 *reloc_addr
= (size_t)base
+ addend
;
399 if (sym
) *reloc_addr
= sym_val
+ addend
;
400 else *reloc_addr
= (size_t)base
+ addend
;
403 memcpy(reloc_addr
, (void *)sym_val
, sym
->st_size
);
406 *(uint32_t *)reloc_addr
= sym_val
+ addend
407 - (size_t)reloc_addr
;
410 *reloc_addr
= def
.sym
? (size_t)(def
.dso
->funcdescs
411 + (def
.sym
- def
.dso
->syms
)) : 0;
413 case REL_FUNCDESC_VAL
:
414 if ((sym
->st_info
&0xf) == STT_SECTION
) *reloc_addr
+= sym_val
;
415 else *reloc_addr
= sym_val
;
416 reloc_addr
[1] = def
.sym
? (size_t)def
.dso
->got
: 0;
419 *reloc_addr
= def
.dso
->tls_id
;
422 *reloc_addr
= tls_val
+ addend
- DTP_OFFSET
;
426 *reloc_addr
= tls_val
+ def
.dso
->tls
.offset
+ TPOFF_K
+ addend
;
430 *reloc_addr
= tls_val
- def
.dso
->tls
.offset
+ addend
;
433 *reloc_addr
= def
.dso
->tls
.offset
- tls_val
+ addend
;
437 if (stride
<3) addend
= reloc_addr
[1];
438 if (runtime
&& def
.dso
->tls_id
> static_tls_cnt
) {
439 struct td_index
*new = malloc(sizeof *new);
442 "Error relocating %s: cannot allocate TLSDESC for %s",
443 dso
->name
, sym
? name
: "(local)" );
444 longjmp(*rtld_fail
, 1);
446 new->next
= dso
->td_index
;
448 new->args
[0] = def
.dso
->tls_id
;
449 new->args
[1] = tls_val
+ addend
- DTP_OFFSET
;
450 reloc_addr
[0] = (size_t)__tlsdesc_dynamic
;
451 reloc_addr
[1] = (size_t)new;
453 reloc_addr
[0] = (size_t)__tlsdesc_static
;
455 reloc_addr
[1] = tls_val
+ def
.dso
->tls
.offset
458 reloc_addr
[1] = tls_val
- def
.dso
->tls
.offset
462 #ifdef TLSDESC_BACKWARDS
463 /* Some archs (32-bit ARM at least) invert the order of
464 * the descriptor members. Fix them up here. */
465 size_t tmp
= reloc_addr
[0];
466 reloc_addr
[0] = reloc_addr
[1];
471 error("Error relocating %s: unsupported relocation type %d",
473 if (runtime
) longjmp(*rtld_fail
, 1);
479 static void redo_lazy_relocs()
481 struct dso
*p
= lazy_head
, *next
;
485 size_t size
= p
->lazy_cnt
*3*sizeof(size_t);
487 do_relocs(p
, p
->lazy
, size
, 3);
489 p
->lazy_next
= lazy_head
;
499 /* A huge hack: to make up for the wastefulness of shared libraries
500 * needing at least a page of dirty memory even if they have no global
501 * data, we reclaim the gaps at the beginning and end of writable maps
502 * and "donate" them to the heap. */
504 static void reclaim(struct dso
*dso
, size_t start
, size_t end
)
506 if (start
>= dso
->relro_start
&& start
< dso
->relro_end
) start
= dso
->relro_end
;
507 if (end
>= dso
->relro_start
&& end
< dso
->relro_end
) end
= dso
->relro_start
;
508 if (start
>= end
) return;
509 char *base
= laddr_pg(dso
, start
);
510 __malloc_donate(base
, base
+(end
-start
));
513 static void reclaim_gaps(struct dso
*dso
)
515 Phdr
*ph
= dso
->phdr
;
516 size_t phcnt
= dso
->phnum
;
518 for (; phcnt
--; ph
=(void *)((char *)ph
+dso
->phentsize
)) {
519 if (ph
->p_type
!=PT_LOAD
) continue;
520 if ((ph
->p_flags
&(PF_R
|PF_W
))!=(PF_R
|PF_W
)) continue;
521 reclaim(dso
, ph
->p_vaddr
& -PAGE_SIZE
, ph
->p_vaddr
);
522 reclaim(dso
, ph
->p_vaddr
+ph
->p_memsz
,
523 ph
->p_vaddr
+ph
->p_memsz
+PAGE_SIZE
-1 & -PAGE_SIZE
);
527 static void *mmap_fixed(void *p
, size_t n
, int prot
, int flags
, int fd
, off_t off
)
529 static int no_map_fixed
;
532 q
= mmap(p
, n
, prot
, flags
|MAP_FIXED
, fd
, off
);
533 if (!DL_NOMMU_SUPPORT
|| q
!= MAP_FAILED
|| errno
!= EINVAL
)
537 /* Fallbacks for MAP_FIXED failure on NOMMU kernels. */
538 if (flags
& MAP_ANONYMOUS
) {
543 if (lseek(fd
, off
, SEEK_SET
) < 0) return MAP_FAILED
;
544 for (q
=p
; n
; q
+=r
, off
+=r
, n
-=r
) {
546 if (r
< 0 && errno
!= EINTR
) return MAP_FAILED
;
555 static void unmap_library(struct dso
*dso
)
559 for (i
=0; i
<dso
->loadmap
->nsegs
; i
++) {
560 if (!dso
->loadmap
->segs
[i
].p_memsz
)
562 munmap((void *)dso
->loadmap
->segs
[i
].addr
,
563 dso
->loadmap
->segs
[i
].p_memsz
);
566 } else if (dso
->map
&& dso
->map_len
) {
567 munmap(dso
->map
, dso
->map_len
);
571 static void *map_library(int fd
, struct dso
*dso
)
573 Ehdr buf
[(896+sizeof(Ehdr
))/sizeof(Ehdr
)];
574 void *allocated_buf
=0;
576 size_t addr_min
=SIZE_MAX
, addr_max
=0, map_len
;
577 size_t this_min
, this_max
;
583 unsigned char *map
=MAP_FAILED
, *base
;
588 ssize_t l
= read(fd
, buf
, sizeof buf
);
591 if (l
<sizeof *eh
|| (eh
->e_type
!= ET_DYN
&& eh
->e_type
!= ET_EXEC
))
593 phsize
= eh
->e_phentsize
* eh
->e_phnum
;
594 if (phsize
> sizeof buf
- sizeof *eh
) {
595 allocated_buf
= malloc(phsize
);
596 if (!allocated_buf
) return 0;
597 l
= pread(fd
, allocated_buf
, phsize
, eh
->e_phoff
);
598 if (l
< 0) goto error
;
599 if (l
!= phsize
) goto noexec
;
600 ph
= ph0
= allocated_buf
;
601 } else if (eh
->e_phoff
+ phsize
> l
) {
602 l
= pread(fd
, buf
+1, phsize
, eh
->e_phoff
);
603 if (l
< 0) goto error
;
604 if (l
!= phsize
) goto noexec
;
605 ph
= ph0
= (void *)(buf
+ 1);
607 ph
= ph0
= (void *)((char *)buf
+ eh
->e_phoff
);
609 for (i
=eh
->e_phnum
; i
; i
--, ph
=(void *)((char *)ph
+eh
->e_phentsize
)) {
610 if (ph
->p_type
== PT_DYNAMIC
) {
612 } else if (ph
->p_type
== PT_TLS
) {
613 tls_image
= ph
->p_vaddr
;
614 dso
->tls
.align
= ph
->p_align
;
615 dso
->tls
.len
= ph
->p_filesz
;
616 dso
->tls
.size
= ph
->p_memsz
;
617 } else if (ph
->p_type
== PT_GNU_RELRO
) {
618 dso
->relro_start
= ph
->p_vaddr
& -PAGE_SIZE
;
619 dso
->relro_end
= (ph
->p_vaddr
+ ph
->p_memsz
) & -PAGE_SIZE
;
620 } else if (ph
->p_type
== PT_GNU_STACK
) {
621 if (!runtime
&& ph
->p_memsz
> __default_stacksize
) {
622 __default_stacksize
=
623 ph
->p_memsz
< DEFAULT_STACK_MAX
?
624 ph
->p_memsz
: DEFAULT_STACK_MAX
;
627 if (ph
->p_type
!= PT_LOAD
) continue;
629 if (ph
->p_vaddr
< addr_min
) {
630 addr_min
= ph
->p_vaddr
;
631 off_start
= ph
->p_offset
;
632 prot
= (((ph
->p_flags
&PF_R
) ? PROT_READ
: 0) |
633 ((ph
->p_flags
&PF_W
) ? PROT_WRITE
: 0) |
634 ((ph
->p_flags
&PF_X
) ? PROT_EXEC
: 0));
636 if (ph
->p_vaddr
+ph
->p_memsz
> addr_max
) {
637 addr_max
= ph
->p_vaddr
+ph
->p_memsz
;
640 if (!dyn
) goto noexec
;
641 if (DL_FDPIC
&& !(eh
->e_flags
& FDPIC_CONSTDISP_FLAG
)) {
642 dso
->loadmap
= calloc(1, sizeof *dso
->loadmap
643 + nsegs
* sizeof *dso
->loadmap
->segs
);
644 if (!dso
->loadmap
) goto error
;
645 dso
->loadmap
->nsegs
= nsegs
;
646 for (ph
=ph0
, i
=0; i
<nsegs
; ph
=(void *)((char *)ph
+eh
->e_phentsize
)) {
647 if (ph
->p_type
!= PT_LOAD
) continue;
648 prot
= (((ph
->p_flags
&PF_R
) ? PROT_READ
: 0) |
649 ((ph
->p_flags
&PF_W
) ? PROT_WRITE
: 0) |
650 ((ph
->p_flags
&PF_X
) ? PROT_EXEC
: 0));
651 map
= mmap(0, ph
->p_memsz
+ (ph
->p_vaddr
& PAGE_SIZE
-1),
653 fd
, ph
->p_offset
& -PAGE_SIZE
);
654 if (map
== MAP_FAILED
) {
658 dso
->loadmap
->segs
[i
].addr
= (size_t)map
+
659 (ph
->p_vaddr
& PAGE_SIZE
-1);
660 dso
->loadmap
->segs
[i
].p_vaddr
= ph
->p_vaddr
;
661 dso
->loadmap
->segs
[i
].p_memsz
= ph
->p_memsz
;
663 if (prot
& PROT_WRITE
) {
664 size_t brk
= (ph
->p_vaddr
& PAGE_SIZE
-1)
666 size_t pgbrk
= brk
+ PAGE_SIZE
-1 & -PAGE_SIZE
;
667 size_t pgend
= brk
+ ph
->p_memsz
- ph
->p_filesz
668 + PAGE_SIZE
-1 & -PAGE_SIZE
;
669 if (pgend
> pgbrk
&& mmap_fixed(map
+pgbrk
,
671 MAP_PRIVATE
|MAP_FIXED
|MAP_ANONYMOUS
,
672 -1, off_start
) == MAP_FAILED
)
674 memset(map
+ brk
, 0, pgbrk
-brk
);
677 map
= (void *)dso
->loadmap
->segs
[0].addr
;
681 addr_max
+= PAGE_SIZE
-1;
682 addr_max
&= -PAGE_SIZE
;
683 addr_min
&= -PAGE_SIZE
;
684 off_start
&= -PAGE_SIZE
;
685 map_len
= addr_max
- addr_min
+ off_start
;
686 /* The first time, we map too much, possibly even more than
687 * the length of the file. This is okay because we will not
688 * use the invalid part; we just need to reserve the right
689 * amount of virtual address space to map over later. */
690 map
= DL_NOMMU_SUPPORT
691 ? mmap((void *)addr_min
, map_len
, PROT_READ
|PROT_WRITE
|PROT_EXEC
,
692 MAP_PRIVATE
|MAP_ANONYMOUS
, -1, 0)
693 : mmap((void *)addr_min
, map_len
, prot
,
694 MAP_PRIVATE
, fd
, off_start
);
695 if (map
==MAP_FAILED
) goto error
;
697 dso
->map_len
= map_len
;
698 /* If the loaded file is not relocatable and the requested address is
699 * not available, then the load operation must fail. */
700 if (eh
->e_type
!= ET_DYN
&& addr_min
&& map
!=(void *)addr_min
) {
704 base
= map
- addr_min
;
707 for (ph
=ph0
, i
=eh
->e_phnum
; i
; i
--, ph
=(void *)((char *)ph
+eh
->e_phentsize
)) {
708 if (ph
->p_type
!= PT_LOAD
) continue;
709 /* Check if the programs headers are in this load segment, and
710 * if so, record the address for use by dl_iterate_phdr. */
711 if (!dso
->phdr
&& eh
->e_phoff
>= ph
->p_offset
712 && eh
->e_phoff
+phsize
<= ph
->p_offset
+ph
->p_filesz
) {
713 dso
->phdr
= (void *)(base
+ ph
->p_vaddr
714 + (eh
->e_phoff
-ph
->p_offset
));
715 dso
->phnum
= eh
->e_phnum
;
716 dso
->phentsize
= eh
->e_phentsize
;
718 this_min
= ph
->p_vaddr
& -PAGE_SIZE
;
719 this_max
= ph
->p_vaddr
+ph
->p_memsz
+PAGE_SIZE
-1 & -PAGE_SIZE
;
720 off_start
= ph
->p_offset
& -PAGE_SIZE
;
721 prot
= (((ph
->p_flags
&PF_R
) ? PROT_READ
: 0) |
722 ((ph
->p_flags
&PF_W
) ? PROT_WRITE
: 0) |
723 ((ph
->p_flags
&PF_X
) ? PROT_EXEC
: 0));
724 /* Reuse the existing mapping for the lowest-address LOAD */
725 if ((ph
->p_vaddr
& -PAGE_SIZE
) != addr_min
|| DL_NOMMU_SUPPORT
)
726 if (mmap_fixed(base
+this_min
, this_max
-this_min
, prot
, MAP_PRIVATE
|MAP_FIXED
, fd
, off_start
) == MAP_FAILED
)
728 if (ph
->p_memsz
> ph
->p_filesz
&& (ph
->p_flags
&PF_W
)) {
729 size_t brk
= (size_t)base
+ph
->p_vaddr
+ph
->p_filesz
;
730 size_t pgbrk
= brk
+PAGE_SIZE
-1 & -PAGE_SIZE
;
731 memset((void *)brk
, 0, pgbrk
-brk
& PAGE_SIZE
-1);
732 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
)
736 for (i
=0; ((size_t *)(base
+dyn
))[i
]; i
+=2)
737 if (((size_t *)(base
+dyn
))[i
]==DT_TEXTREL
) {
738 if (mprotect(map
, map_len
, PROT_READ
|PROT_WRITE
|PROT_EXEC
)
745 dso
->dynv
= laddr(dso
, dyn
);
746 if (dso
->tls
.size
) dso
->tls
.image
= laddr(dso
, tls_image
);
752 if (map
!=MAP_FAILED
) unmap_library(dso
);
757 static int path_open(const char *name
, const char *s
, char *buf
, size_t buf_size
)
762 s
+= strspn(s
, ":\n");
763 l
= strcspn(s
, ":\n");
764 if (l
-1 >= INT_MAX
) return -1;
765 if (snprintf(buf
, buf_size
, "%.*s/%s", (int)l
, s
, name
) < buf_size
) {
766 if ((fd
= open(buf
, O_RDONLY
|O_CLOEXEC
))>=0) return fd
;
774 /* Any negative value but -1 will inhibit
775 * futher path search. */
783 static int fixup_rpath(struct dso
*p
, char *buf
, size_t buf_size
)
786 const char *s
, *t
, *origin
;
788 if (p
->rpath
|| !p
->rpath_orig
) return 0;
789 if (!strchr(p
->rpath_orig
, '$')) {
790 p
->rpath
= p
->rpath_orig
;
795 while ((t
=strchr(s
, '$'))) {
796 if (strncmp(t
, "$ORIGIN", 7) && strncmp(t
, "${ORIGIN}", 9))
801 if (n
> SSIZE_MAX
/PATH_MAX
) return 0;
803 if (p
->kernel_mapped
) {
804 /* $ORIGIN searches cannot be performed for the main program
805 * when it is suid/sgid/AT_SECURE. This is because the
806 * pathname is under the control of the caller of execve.
807 * For libraries, however, $ORIGIN can be processed safely
808 * since the library's pathname came from a trusted source
809 * (either system paths or a call to dlopen). */
812 l
= readlink("/proc/self/exe", buf
, buf_size
);
813 if (l
== -1) switch (errno
) {
828 t
= strrchr(origin
, '/');
832 /* Normally p->name will always be an absolute or relative
833 * pathname containing at least one '/' character, but in the
834 * case where ldso was invoked as a command to execute a
835 * program in the working directory, app.name may not. Fix. */
839 /* Disallow non-absolute origins for suid/sgid/AT_SECURE. */
840 if (libc
.secure
&& *origin
!= '/')
842 p
->rpath
= malloc(strlen(p
->rpath_orig
) + n
*l
+ 1);
843 if (!p
->rpath
) return -1;
847 while ((t
=strchr(s
, '$'))) {
850 memcpy(d
, origin
, l
);
852 /* It was determined previously that the '$' is followed
853 * either by "ORIGIN" or "{ORIGIN}". */
854 s
= t
+ 7 + 2*(t
[1]=='{');
860 static void decode_dyn(struct dso
*p
)
863 decode_vec(p
->dynv
, dyn
, DYN_CNT
);
864 p
->syms
= laddr(p
, dyn
[DT_SYMTAB
]);
865 p
->strings
= laddr(p
, dyn
[DT_STRTAB
]);
866 if (dyn
[0]&(1<<DT_HASH
))
867 p
->hashtab
= laddr(p
, dyn
[DT_HASH
]);
868 if (dyn
[0]&(1<<DT_RPATH
))
869 p
->rpath_orig
= p
->strings
+ dyn
[DT_RPATH
];
870 if (dyn
[0]&(1<<DT_RUNPATH
))
871 p
->rpath_orig
= p
->strings
+ dyn
[DT_RUNPATH
];
872 if (dyn
[0]&(1<<DT_PLTGOT
))
873 p
->got
= laddr(p
, dyn
[DT_PLTGOT
]);
874 if (search_vec(p
->dynv
, dyn
, DT_GNU_HASH
))
875 p
->ghashtab
= laddr(p
, *dyn
);
876 if (search_vec(p
->dynv
, dyn
, DT_VERSYM
))
877 p
->versym
= laddr(p
, *dyn
);
880 static size_t count_syms(struct dso
*p
)
882 if (p
->hashtab
) return p
->hashtab
[1];
885 uint32_t *buckets
= p
->ghashtab
+ 4 + (p
->ghashtab
[2]*sizeof(size_t)/4);
887 for (i
= nsym
= 0; i
< p
->ghashtab
[0]; i
++) {
888 if (buckets
[i
] > nsym
)
892 hashval
= buckets
+ p
->ghashtab
[0] + (nsym
- p
->ghashtab
[1]);
894 while (!(*hashval
++ & 1));
899 static void *dl_mmap(size_t n
)
902 int prot
= PROT_READ
|PROT_WRITE
, flags
= MAP_ANONYMOUS
|MAP_PRIVATE
;
904 p
= (void *)__syscall(SYS_mmap2
, 0, n
, prot
, flags
, -1, 0);
906 p
= (void *)__syscall(SYS_mmap
, 0, n
, prot
, flags
, -1, 0);
908 return p
== MAP_FAILED
? 0 : p
;
911 static void makefuncdescs(struct dso
*p
)
913 static int self_done
;
914 size_t nsym
= count_syms(p
);
915 size_t i
, size
= nsym
* sizeof(*p
->funcdescs
);
918 p
->funcdescs
= dl_mmap(size
);
921 p
->funcdescs
= malloc(size
);
924 if (!runtime
) a_crash();
925 error("Error allocating function descriptors for %s", p
->name
);
926 longjmp(*rtld_fail
, 1);
928 for (i
=0; i
<nsym
; i
++) {
929 if ((p
->syms
[i
].st_info
&0xf)==STT_FUNC
&& p
->syms
[i
].st_shndx
) {
930 p
->funcdescs
[i
].addr
= laddr(p
, p
->syms
[i
].st_value
);
931 p
->funcdescs
[i
].got
= p
->got
;
933 p
->funcdescs
[i
].addr
= 0;
934 p
->funcdescs
[i
].got
= 0;
939 static struct dso
*load_library(const char *name
, struct dso
*needed_by
)
941 char buf
[2*NAME_MAX
+2];
942 const char *pathname
;
944 struct dso
*p
, temp_dso
= {0};
956 /* Catch and block attempts to reload the implementation itself */
957 if (name
[0]=='l' && name
[1]=='i' && name
[2]=='b') {
958 static const char reserved
[] =
959 "c.pthread.rt.m.dl.util.xnet.";
960 const char *rp
, *next
;
961 for (rp
=reserved
; *rp
; rp
=next
) {
962 next
= strchr(rp
, '.') + 1;
963 if (strncmp(name
+3, rp
, next
-rp
) == 0)
968 /* Track which names have been resolved
969 * and only report each one once. */
970 static unsigned reported
;
971 unsigned mask
= 1U<<(rp
-reserved
);
972 if (!(reported
& mask
)) {
974 dprintf(1, "\t%s => %s (%p)\n",
982 if (!strcmp(name
, ldso
.name
)) is_self
= 1;
991 if (strchr(name
, '/')) {
993 fd
= open(name
, O_RDONLY
|O_CLOEXEC
);
995 /* Search for the name to see if it's already loaded */
996 for (p
=head
->next
; p
; p
=p
->next
) {
997 if (p
->shortname
&& !strcmp(p
->shortname
, name
)) {
1001 if (strlen(name
) > NAME_MAX
) return 0;
1003 if (env_path
) fd
= path_open(name
, env_path
, buf
, sizeof buf
);
1004 for (p
=needed_by
; fd
== -1 && p
; p
=p
->needed_by
) {
1005 if (fixup_rpath(p
, buf
, sizeof buf
) < 0)
1006 fd
= -2; /* Inhibit further search. */
1008 fd
= path_open(name
, p
->rpath
, buf
, sizeof buf
);
1014 if (ldso
.name
[0]=='/') {
1016 for (s
=t
=z
=ldso
.name
; *s
; s
++)
1017 if (*s
=='/') z
=t
, t
=s
;
1018 prefix_len
= z
-ldso
.name
;
1019 if (prefix_len
< PATH_MAX
)
1026 char etc_ldso_path
[prefix_len
+ 1
1027 + sizeof "/etc/ld-musl-" LDSO_ARCH
".path"];
1028 snprintf(etc_ldso_path
, sizeof etc_ldso_path
,
1029 "%.*s/etc/ld-musl-" LDSO_ARCH
".path",
1030 (int)prefix_len
, prefix
);
1031 FILE *f
= fopen(etc_ldso_path
, "rbe");
1033 if (getdelim(&sys_path
, (size_t[1]){0}, 0, f
) <= 0) {
1038 } else if (errno
!= ENOENT
) {
1042 if (!sys_path
) sys_path
= "/lib:/usr/local/lib:/usr/lib";
1043 fd
= path_open(name
, sys_path
, buf
, sizeof buf
);
1047 if (fd
< 0) return 0;
1048 if (fstat(fd
, &st
) < 0) {
1052 for (p
=head
->next
; p
; p
=p
->next
) {
1053 if (p
->dev
== st
.st_dev
&& p
->ino
== st
.st_ino
) {
1054 /* If this library was previously loaded with a
1055 * pathname but a search found the same inode,
1056 * setup its shortname so it can be found by name. */
1057 if (!p
->shortname
&& pathname
!= name
)
1058 p
->shortname
= strrchr(p
->name
, '/')+1;
1063 map
= noload
? 0 : map_library(fd
, &temp_dso
);
1067 /* Avoid the danger of getting two versions of libc mapped into the
1068 * same process when an absolute pathname was used. The symbols
1069 * checked are chosen to catch both musl and glibc, and to avoid
1070 * false positives from interposition-hack libraries. */
1071 decode_dyn(&temp_dso
);
1072 if (find_sym(&temp_dso
, "__libc_start_main", 1).sym
&&
1073 find_sym(&temp_dso
, "stdin", 1).sym
) {
1074 unmap_library(&temp_dso
);
1075 return load_library("libc.so", needed_by
);
1077 /* Past this point, if we haven't reached runtime yet, ldso has
1078 * committed either to use the mapped library or to abort execution.
1079 * Unmapping is not possible, so we can safely reclaim gaps. */
1080 if (!runtime
) reclaim_gaps(&temp_dso
);
1082 /* Allocate storage for the new DSO. When there is TLS, this
1083 * storage must include a reservation for all pre-existing
1084 * threads to obtain copies of both the new TLS, and an
1085 * extended DTV capable of storing an additional slot for
1086 * the newly-loaded DSO. */
1087 alloc_size
= sizeof *p
+ strlen(pathname
) + 1;
1088 if (runtime
&& temp_dso
.tls
.image
) {
1089 size_t per_th
= temp_dso
.tls
.size
+ temp_dso
.tls
.align
1090 + sizeof(void *) * (tls_cnt
+3);
1091 n_th
= libc
.threads_minus_1
+ 1;
1092 if (n_th
> SSIZE_MAX
/ per_th
) alloc_size
= SIZE_MAX
;
1093 else alloc_size
+= n_th
* per_th
;
1095 p
= calloc(1, alloc_size
);
1097 unmap_library(&temp_dso
);
1100 memcpy(p
, &temp_dso
, sizeof temp_dso
);
1103 p
->needed_by
= needed_by
;
1105 strcpy(p
->name
, pathname
);
1106 /* Add a shortname only if name arg was not an explicit pathname. */
1107 if (pathname
!= name
) p
->shortname
= strrchr(p
->name
, '/')+1;
1109 p
->tls_id
= ++tls_cnt
;
1110 tls_align
= MAXP2(tls_align
, p
->tls
.align
);
1112 p
->tls
.offset
= tls_offset
+ ( (tls_align
-1) &
1113 -(tls_offset
+ (uintptr_t)p
->tls
.image
) );
1114 tls_offset
+= p
->tls
.size
;
1116 tls_offset
+= p
->tls
.size
+ p
->tls
.align
- 1;
1117 tls_offset
-= (tls_offset
+ (uintptr_t)p
->tls
.image
)
1119 p
->tls
.offset
= tls_offset
;
1121 p
->new_dtv
= (void *)(-sizeof(size_t) &
1122 (uintptr_t)(p
->name
+strlen(p
->name
)+sizeof(size_t)));
1123 p
->new_tls
= (void *)(p
->new_dtv
+ n_th
*(tls_cnt
+1));
1124 if (tls_tail
) tls_tail
->next
= &p
->tls
;
1125 else libc
.tls_head
= &p
->tls
;
1133 if (DL_FDPIC
) makefuncdescs(p
);
1135 if (ldd_mode
) dprintf(1, "\t%s => %s (%p)\n", name
, pathname
, p
->base
);
1140 static void load_deps(struct dso
*p
)
1143 struct dso
***deps
= &p
->deps
, **tmp
, *dep
;
1144 for (; p
; p
=p
->next
) {
1145 for (i
=0; p
->dynv
[i
]; i
+=2) {
1146 if (p
->dynv
[i
] != DT_NEEDED
) continue;
1147 dep
= load_library(p
->strings
+ p
->dynv
[i
+1], p
);
1149 error("Error loading shared library %s: %m (needed by %s)",
1150 p
->strings
+ p
->dynv
[i
+1], p
->name
);
1151 if (runtime
) longjmp(*rtld_fail
, 1);
1155 tmp
= realloc(*deps
, sizeof(*tmp
)*(ndeps
+2));
1156 if (!tmp
) longjmp(*rtld_fail
, 1);
1163 if (!*deps
) *deps
= (struct dso
**)&nodeps_dummy
;
1166 static void load_preload(char *s
)
1170 for (z
=s
; *z
; s
=z
) {
1171 for ( ; *s
&& (isspace(*s
) || *s
==':'); s
++);
1172 for (z
=s
; *z
&& !isspace(*z
) && *z
!=':'; z
++);
1180 static void add_syms(struct dso
*p
)
1182 if (!p
->syms_next
&& syms_tail
!= p
) {
1183 syms_tail
->syms_next
= p
;
1188 static void revert_syms(struct dso
*old_tail
)
1190 struct dso
*p
, *next
;
1191 /* Chop off the tail of the list of dsos that participate in
1192 * the global symbol table, reverting them to RTLD_LOCAL. */
1193 for (p
=old_tail
; p
; p
=next
) {
1194 next
= p
->syms_next
;
1197 syms_tail
= old_tail
;
1200 static void do_mips_relocs(struct dso
*p
, size_t *got
)
1202 size_t i
, j
, rel
[2];
1203 unsigned char *base
= p
->base
;
1204 i
=0; search_vec(p
->dynv
, &i
, DT_MIPS_LOCAL_GOTNO
);
1208 while (i
--) *got
++ += (size_t)base
;
1210 j
=0; search_vec(p
->dynv
, &j
, DT_MIPS_GOTSYM
);
1211 i
=0; search_vec(p
->dynv
, &i
, DT_MIPS_SYMTABNO
);
1212 Sym
*sym
= p
->syms
+ j
;
1213 rel
[0] = (unsigned char *)got
- base
;
1214 for (i
-=j
; i
; i
--, sym
++, rel
[0]+=sizeof(size_t)) {
1215 rel
[1] = R_INFO(sym
-p
->syms
, R_MIPS_JUMP_SLOT
);
1216 do_relocs(p
, rel
, sizeof rel
, 2);
1220 static void reloc_all(struct dso
*p
)
1222 size_t dyn
[DYN_CNT
];
1223 for (; p
; p
=p
->next
) {
1224 if (p
->relocated
) continue;
1225 decode_vec(p
->dynv
, dyn
, DYN_CNT
);
1226 if (NEED_MIPS_GOT_RELOCS
)
1227 do_mips_relocs(p
, laddr(p
, dyn
[DT_PLTGOT
]));
1228 do_relocs(p
, laddr(p
, dyn
[DT_JMPREL
]), dyn
[DT_PLTRELSZ
],
1229 2+(dyn
[DT_PLTREL
]==DT_RELA
));
1230 do_relocs(p
, laddr(p
, dyn
[DT_REL
]), dyn
[DT_RELSZ
], 2);
1231 do_relocs(p
, laddr(p
, dyn
[DT_RELA
]), dyn
[DT_RELASZ
], 3);
1233 if (head
!= &ldso
&& p
->relro_start
!= p
->relro_end
&&
1234 mprotect(laddr(p
, p
->relro_start
), p
->relro_end
-p
->relro_start
, PROT_READ
)
1235 && errno
!= ENOSYS
) {
1236 error("Error relocating %s: RELRO protection failed: %m",
1238 if (runtime
) longjmp(*rtld_fail
, 1);
1245 static void kernel_mapped_dso(struct dso
*p
)
1247 size_t min_addr
= -1, max_addr
= 0, cnt
;
1249 for (cnt
= p
->phnum
; cnt
--; ph
= (void *)((char *)ph
+ p
->phentsize
)) {
1250 if (ph
->p_type
== PT_DYNAMIC
) {
1251 p
->dynv
= laddr(p
, ph
->p_vaddr
);
1252 } else if (ph
->p_type
== PT_GNU_RELRO
) {
1253 p
->relro_start
= ph
->p_vaddr
& -PAGE_SIZE
;
1254 p
->relro_end
= (ph
->p_vaddr
+ ph
->p_memsz
) & -PAGE_SIZE
;
1255 } else if (ph
->p_type
== PT_GNU_STACK
) {
1256 if (!runtime
&& ph
->p_memsz
> __default_stacksize
) {
1257 __default_stacksize
=
1258 ph
->p_memsz
< DEFAULT_STACK_MAX
?
1259 ph
->p_memsz
: DEFAULT_STACK_MAX
;
1262 if (ph
->p_type
!= PT_LOAD
) continue;
1263 if (ph
->p_vaddr
< min_addr
)
1264 min_addr
= ph
->p_vaddr
;
1265 if (ph
->p_vaddr
+ph
->p_memsz
> max_addr
)
1266 max_addr
= ph
->p_vaddr
+ph
->p_memsz
;
1268 min_addr
&= -PAGE_SIZE
;
1269 max_addr
= (max_addr
+ PAGE_SIZE
-1) & -PAGE_SIZE
;
1270 p
->map
= p
->base
+ min_addr
;
1271 p
->map_len
= max_addr
- min_addr
;
1272 p
->kernel_mapped
= 1;
1275 void __libc_exit_fini()
1278 size_t dyn
[DYN_CNT
];
1279 for (p
=fini_head
; p
; p
=p
->fini_next
) {
1280 if (!p
->constructed
) continue;
1281 decode_vec(p
->dynv
, dyn
, DYN_CNT
);
1282 if (dyn
[0] & (1<<DT_FINI_ARRAY
)) {
1283 size_t n
= dyn
[DT_FINI_ARRAYSZ
]/sizeof(size_t);
1284 size_t *fn
= (size_t *)laddr(p
, dyn
[DT_FINI_ARRAY
])+n
;
1285 while (n
--) ((void (*)(void))*--fn
)();
1287 #ifndef NO_LEGACY_INITFINI
1288 if ((dyn
[0] & (1<<DT_FINI
)) && dyn
[DT_FINI
])
1289 fpaddr(p
, dyn
[DT_FINI
])();
1294 static void do_init_fini(struct dso
*p
)
1296 size_t dyn
[DYN_CNT
];
1297 int need_locking
= libc
.threads_minus_1
;
1298 /* Allow recursive calls that arise when a library calls
1299 * dlopen from one of its constructors, but block any
1300 * other threads until all ctors have finished. */
1301 if (need_locking
) pthread_mutex_lock(&init_fini_lock
);
1302 for (; p
; p
=p
->prev
) {
1303 if (p
->constructed
) continue;
1305 decode_vec(p
->dynv
, dyn
, DYN_CNT
);
1306 if (dyn
[0] & ((1<<DT_FINI
) | (1<<DT_FINI_ARRAY
))) {
1307 p
->fini_next
= fini_head
;
1310 #ifndef NO_LEGACY_INITFINI
1311 if ((dyn
[0] & (1<<DT_INIT
)) && dyn
[DT_INIT
])
1312 fpaddr(p
, dyn
[DT_INIT
])();
1314 if (dyn
[0] & (1<<DT_INIT_ARRAY
)) {
1315 size_t n
= dyn
[DT_INIT_ARRAYSZ
]/sizeof(size_t);
1316 size_t *fn
= laddr(p
, dyn
[DT_INIT_ARRAY
]);
1317 while (n
--) ((void (*)(void))*fn
++)();
1319 if (!need_locking
&& libc
.threads_minus_1
) {
1321 pthread_mutex_lock(&init_fini_lock
);
1324 if (need_locking
) pthread_mutex_unlock(&init_fini_lock
);
1327 void __libc_start_init(void)
1332 static void dl_debug_state(void)
1336 weak_alias(dl_debug_state
, _dl_debug_state
);
1338 void __init_tls(size_t *auxv
)
1342 static void update_tls_size()
1344 libc
.tls_cnt
= tls_cnt
;
1345 libc
.tls_align
= tls_align
;
1346 libc
.tls_size
= ALIGN(
1347 (1+tls_cnt
) * sizeof(void *) +
1349 sizeof(struct pthread
) +
1354 void __dl_prepare_for_threads(void)
1356 /* MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED */
1357 __syscall(SYS_membarrier
, 1<<4, 0);
1360 static sem_t barrier_sem
;
1361 static void bcast_barrier(int s
)
1363 sem_post(&barrier_sem
);
1366 static void install_new_tls(void)
1369 pthread_t self
= __pthread_self(), td
;
1370 uintptr_t (*newdtv
)[tls_cnt
+1] = (void *)tail
->new_dtv
;
1373 size_t old_cnt
= self
->dtv
[0];
1375 __block_app_sigs(&set
);
1377 /* Copy existing dtv contents from all existing threads. */
1378 for (i
=0, td
=self
; !i
|| td
!=self
; i
++, td
=td
->next
) {
1379 memcpy(newdtv
+i
, td
->dtv
,
1380 (old_cnt
+1)*sizeof(uintptr_t));
1381 newdtv
[i
][0] = tls_cnt
;
1383 /* Install new dtls into the enlarged, uninstalled dtv copies. */
1384 for (p
=head
; ; p
=p
->next
) {
1385 if (!p
->tls_id
|| self
->dtv
[p
->tls_id
]) continue;
1386 unsigned char *mem
= p
->new_tls
;
1387 for (j
=0; j
<i
; j
++) {
1388 unsigned char *new = mem
;
1389 new += ((uintptr_t)p
->tls
.image
- (uintptr_t)mem
)
1391 memcpy(new, p
->tls
.image
, p
->tls
.len
);
1392 newdtv
[j
][p
->tls_id
] =
1393 (uintptr_t)new + DTP_OFFSET
;
1394 mem
+= p
->tls
.size
+ p
->tls
.align
;
1396 if (p
->tls_id
== tls_cnt
) break;
1399 /* Broadcast barrier to ensure contents of new dtv is visible
1400 * if the new dtv pointer is. Use SYS_membarrier if it works,
1401 * otherwise emulate with a signal. */
1403 /* MEMBARRIER_CMD_PRIVATE_EXPEDITED */
1404 if (__syscall(SYS_membarrier
, 1<<3, 0)) {
1405 sem_init(&barrier_sem
, 0, 0);
1406 struct sigaction sa
= {
1407 .sa_flags
= SA_RESTART
,
1408 .sa_handler
= bcast_barrier
1410 memset(&sa
.sa_mask
, -1, sizeof sa
.sa_mask
);
1411 __libc_sigaction(SIGSYNCCALL
, &sa
, 0);
1412 for (td
=self
->next
; td
!=self
; td
=td
->next
)
1413 if (j
) __syscall(SYS_tkill
, td
->tid
, SIGSYNCCALL
);
1414 for (td
=self
->next
; td
!=self
; td
=td
->next
)
1415 sem_wait(&barrier_sem
);
1416 sa
.sa_handler
= SIG_IGN
;
1417 __libc_sigaction(SIGSYNCCALL
, &sa
, 0);
1418 sem_destroy(&barrier_sem
);
1421 /* Install new dtv for each thread. */
1422 for (j
=0, td
=self
; !j
|| td
!=self
; j
++, td
=td
->next
) {
1423 td
->dtv
= td
->dtv_copy
= newdtv
[j
];
1427 __restore_sigs(&set
);
1430 /* Stage 1 of the dynamic linker is defined in dlstart.c. It calls the
1431 * following stage 2 and stage 3 functions via primitive symbolic lookup
1432 * since it does not have access to their addresses to begin with. */
1434 /* Stage 2 of the dynamic linker is called after relative relocations
1435 * have been processed. It can make function calls to static functions
1436 * and access string literals and static data, but cannot use extern
1437 * symbols. Its job is to perform symbolic relocations on the dynamic
1438 * linker itself, but some of the relocations performed may need to be
1439 * replaced later due to copy relocations in the main program. */
1441 hidden
void __dls2(unsigned char *base
, size_t *sp
)
1444 void *p1
= (void *)sp
[-2];
1445 void *p2
= (void *)sp
[-1];
1447 size_t *auxv
, aux
[AUX_CNT
];
1448 for (auxv
=sp
+1+*sp
+1; *auxv
; auxv
++);
1450 decode_vec(auxv
, aux
, AUX_CNT
);
1451 if (aux
[AT_BASE
]) ldso
.base
= (void *)aux
[AT_BASE
];
1452 else ldso
.base
= (void *)(aux
[AT_PHDR
] & -4096);
1454 app_loadmap
= p2
? p1
: 0;
1455 ldso
.loadmap
= p2
? p2
: p1
;
1456 ldso
.base
= laddr(&ldso
, 0);
1460 Ehdr
*ehdr
= (void *)ldso
.base
;
1461 ldso
.name
= ldso
.shortname
= "libc.so";
1462 ldso
.phnum
= ehdr
->e_phnum
;
1463 ldso
.phdr
= laddr(&ldso
, ehdr
->e_phoff
);
1464 ldso
.phentsize
= ehdr
->e_phentsize
;
1465 kernel_mapped_dso(&ldso
);
1468 if (DL_FDPIC
) makefuncdescs(&ldso
);
1470 /* Prepare storage for to save clobbered REL addends so they
1471 * can be reused in stage 3. There should be very few. If
1472 * something goes wrong and there are a huge number, abort
1473 * instead of risking stack overflow. */
1474 size_t dyn
[DYN_CNT
];
1475 decode_vec(ldso
.dynv
, dyn
, DYN_CNT
);
1476 size_t *rel
= laddr(&ldso
, dyn
[DT_REL
]);
1477 size_t rel_size
= dyn
[DT_RELSZ
];
1478 size_t symbolic_rel_cnt
= 0;
1479 apply_addends_to
= rel
;
1480 for (; rel_size
; rel
+=2, rel_size
-=2*sizeof(size_t))
1481 if (!IS_RELATIVE(rel
[1], ldso
.syms
)) symbolic_rel_cnt
++;
1482 if (symbolic_rel_cnt
>= ADDEND_LIMIT
) a_crash();
1483 size_t addends
[symbolic_rel_cnt
+1];
1484 saved_addends
= addends
;
1491 /* Call dynamic linker stage-2b, __dls2b, looking it up
1492 * symbolically as a barrier against moving the address
1493 * load across the above relocation processing. */
1494 struct symdef dls2b_def
= find_sym(&ldso
, "__dls2b", 0);
1495 if (DL_FDPIC
) ((stage3_func
)&ldso
.funcdescs
[dls2b_def
.sym
-ldso
.syms
])(sp
);
1496 else ((stage3_func
)laddr(&ldso
, dls2b_def
.sym
->st_value
))(sp
);
1499 /* Stage 2b sets up a valid thread pointer, which requires relocations
1500 * completed in stage 2, and on which stage 3 is permitted to depend.
1501 * This is done as a separate stage, with symbolic lookup as a barrier,
1502 * so that loads of the thread pointer and &errno can be pure/const and
1503 * thereby hoistable. */
1505 _Noreturn
void __dls2b(size_t *sp
)
1507 /* Setup early thread pointer in builtin_tls for ldso/libc itself to
1508 * use during dynamic linking. If possible it will also serve as the
1509 * thread pointer at runtime. */
1510 libc
.tls_size
= sizeof builtin_tls
;
1511 libc
.tls_align
= tls_align
;
1512 if (__init_tp(__copy_tls((void *)builtin_tls
)) < 0) {
1516 struct symdef dls3_def
= find_sym(&ldso
, "__dls3", 0);
1517 if (DL_FDPIC
) ((stage3_func
)&ldso
.funcdescs
[dls3_def
.sym
-ldso
.syms
])(sp
);
1518 else ((stage3_func
)laddr(&ldso
, dls3_def
.sym
->st_value
))(sp
);
1521 /* Stage 3 of the dynamic linker is called with the dynamic linker/libc
1522 * fully functional. Its job is to load (if not already loaded) and
1523 * process dependencies and relocations for the main application and
1524 * transfer control to its entry point. */
1526 _Noreturn
void __dls3(size_t *sp
)
1528 static struct dso app
, vdso
;
1529 size_t aux
[AUX_CNT
], *auxv
;
1531 char *env_preload
=0;
1532 char *replace_argv0
=0;
1535 char **argv
= (void *)(sp
+1);
1536 char **argv_orig
= argv
;
1537 char **envp
= argv
+argc
+1;
1539 /* Find aux vector just past environ[] and use it to initialize
1540 * global data that may be needed before we can make syscalls. */
1542 for (i
=argc
+1; argv
[i
]; i
++);
1543 libc
.auxv
= auxv
= (void *)(argv
+i
+1);
1544 decode_vec(auxv
, aux
, AUX_CNT
);
1545 __hwcap
= aux
[AT_HWCAP
];
1546 libc
.page_size
= aux
[AT_PAGESZ
];
1547 libc
.secure
= ((aux
[0]&0x7800)!=0x7800 || aux
[AT_UID
]!=aux
[AT_EUID
]
1548 || aux
[AT_GID
]!=aux
[AT_EGID
] || aux
[AT_SECURE
]);
1550 /* Only trust user/env if kernel says we're not suid/sgid */
1552 env_path
= getenv("LD_LIBRARY_PATH");
1553 env_preload
= getenv("LD_PRELOAD");
1556 /* If the main program was already loaded by the kernel,
1557 * AT_PHDR will point to some location other than the dynamic
1558 * linker's program headers. */
1559 if (aux
[AT_PHDR
] != (size_t)ldso
.phdr
) {
1560 size_t interp_off
= 0;
1561 size_t tls_image
= 0;
1562 /* Find load address of the main program, via AT_PHDR vs PT_PHDR. */
1563 Phdr
*phdr
= app
.phdr
= (void *)aux
[AT_PHDR
];
1564 app
.phnum
= aux
[AT_PHNUM
];
1565 app
.phentsize
= aux
[AT_PHENT
];
1566 for (i
=aux
[AT_PHNUM
]; i
; i
--, phdr
=(void *)((char *)phdr
+ aux
[AT_PHENT
])) {
1567 if (phdr
->p_type
== PT_PHDR
)
1568 app
.base
= (void *)(aux
[AT_PHDR
] - phdr
->p_vaddr
);
1569 else if (phdr
->p_type
== PT_INTERP
)
1570 interp_off
= (size_t)phdr
->p_vaddr
;
1571 else if (phdr
->p_type
== PT_TLS
) {
1572 tls_image
= phdr
->p_vaddr
;
1573 app
.tls
.len
= phdr
->p_filesz
;
1574 app
.tls
.size
= phdr
->p_memsz
;
1575 app
.tls
.align
= phdr
->p_align
;
1578 if (DL_FDPIC
) app
.loadmap
= app_loadmap
;
1579 if (app
.tls
.size
) app
.tls
.image
= laddr(&app
, tls_image
);
1580 if (interp_off
) ldso
.name
= laddr(&app
, interp_off
);
1581 if ((aux
[0] & (1UL<<AT_EXECFN
))
1582 && strncmp((char *)aux
[AT_EXECFN
], "/proc/", 6))
1583 app
.name
= (char *)aux
[AT_EXECFN
];
1586 kernel_mapped_dso(&app
);
1589 char *ldname
= argv
[0];
1590 size_t l
= strlen(ldname
);
1591 if (l
>= 3 && !strcmp(ldname
+l
-3, "ldd")) ldd_mode
= 1;
1593 while (argv
[0] && argv
[0][0]=='-' && argv
[0][1]=='-') {
1594 char *opt
= argv
[0]+2;
1595 *argv
++ = (void *)-1;
1598 } else if (!memcmp(opt
, "list", 5)) {
1600 } else if (!memcmp(opt
, "library-path", 12)) {
1601 if (opt
[12]=='=') env_path
= opt
+13;
1602 else if (opt
[12]) *argv
= 0;
1603 else if (*argv
) env_path
= *argv
++;
1604 } else if (!memcmp(opt
, "preload", 7)) {
1605 if (opt
[7]=='=') env_preload
= opt
+8;
1606 else if (opt
[7]) *argv
= 0;
1607 else if (*argv
) env_preload
= *argv
++;
1608 } else if (!memcmp(opt
, "argv0", 5)) {
1609 if (opt
[5]=='=') replace_argv0
= opt
+6;
1610 else if (opt
[5]) *argv
= 0;
1611 else if (*argv
) replace_argv0
= *argv
++;
1616 argv
[-1] = (void *)(argc
- (argv
-argv_orig
));
1618 dprintf(2, "musl libc (" LDSO_ARCH
")\n"
1620 "Dynamic Program Loader\n"
1621 "Usage: %s [options] [--] pathname%s\n",
1622 __libc_version
, ldname
,
1623 ldd_mode
? "" : " [args]");
1626 fd
= open(argv
[0], O_RDONLY
);
1628 dprintf(2, "%s: cannot load %s: %s\n", ldname
, argv
[0], strerror(errno
));
1631 Ehdr
*ehdr
= (void *)map_library(fd
, &app
);
1633 dprintf(2, "%s: %s: Not a valid dynamic program\n", ldname
, argv
[0]);
1639 aux
[AT_ENTRY
] = (size_t)laddr(&app
, ehdr
->e_entry
);
1640 /* Find the name that would have been used for the dynamic
1641 * linker had ldd not taken its place. */
1643 for (i
=0; i
<app
.phnum
; i
++) {
1644 if (app
.phdr
[i
].p_type
== PT_INTERP
)
1645 ldso
.name
= laddr(&app
, app
.phdr
[i
].p_vaddr
);
1647 dprintf(1, "\t%s (%p)\n", ldso
.name
, ldso
.base
);
1651 libc
.tls_head
= tls_tail
= &app
.tls
;
1652 app
.tls_id
= tls_cnt
= 1;
1654 app
.tls
.offset
= GAP_ABOVE_TP
;
1655 app
.tls
.offset
+= -GAP_ABOVE_TP
& (app
.tls
.align
-1);
1656 tls_offset
= app
.tls
.offset
+ app
.tls
.size
1657 + ( -((uintptr_t)app
.tls
.image
+ app
.tls
.size
)
1658 & (app
.tls
.align
-1) );
1660 tls_offset
= app
.tls
.offset
= app
.tls
.size
1661 + ( -((uintptr_t)app
.tls
.image
+ app
.tls
.size
)
1662 & (app
.tls
.align
-1) );
1664 tls_align
= MAXP2(tls_align
, app
.tls
.align
);
1668 makefuncdescs(&app
);
1670 app
.loadmap
= (void *)&app_dummy_loadmap
;
1671 app
.loadmap
->nsegs
= 1;
1672 app
.loadmap
->segs
[0].addr
= (size_t)app
.map
;
1673 app
.loadmap
->segs
[0].p_vaddr
= (size_t)app
.map
1675 app
.loadmap
->segs
[0].p_memsz
= app
.map_len
;
1677 argv
[-3] = (void *)app
.loadmap
;
1680 /* Initial dso chain consists only of the app. */
1681 head
= tail
= syms_tail
= &app
;
1683 /* Donate unused parts of app and library mapping to malloc */
1685 reclaim_gaps(&ldso
);
1687 /* Load preload/needed libraries, add symbols to global namespace. */
1688 if (env_preload
) load_preload(env_preload
);
1690 for (struct dso
*p
=head
; p
; p
=p
->next
)
1693 /* Attach to vdso, if provided by the kernel, last so that it does
1694 * not become part of the global namespace. */
1695 if (search_vec(auxv
, &vdso_base
, AT_SYSINFO_EHDR
) && vdso_base
) {
1696 Ehdr
*ehdr
= (void *)vdso_base
;
1697 Phdr
*phdr
= vdso
.phdr
= (void *)(vdso_base
+ ehdr
->e_phoff
);
1698 vdso
.phnum
= ehdr
->e_phnum
;
1699 vdso
.phentsize
= ehdr
->e_phentsize
;
1700 for (i
=ehdr
->e_phnum
; i
; i
--, phdr
=(void *)((char *)phdr
+ ehdr
->e_phentsize
)) {
1701 if (phdr
->p_type
== PT_DYNAMIC
)
1702 vdso
.dynv
= (void *)(vdso_base
+ phdr
->p_offset
);
1703 if (phdr
->p_type
== PT_LOAD
)
1704 vdso
.base
= (void *)(vdso_base
- phdr
->p_vaddr
+ phdr
->p_offset
);
1707 vdso
.shortname
= "linux-gate.so.1";
1715 for (i
=0; app
.dynv
[i
]; i
+=2) {
1716 if (!DT_DEBUG_INDIRECT
&& app
.dynv
[i
]==DT_DEBUG
)
1717 app
.dynv
[i
+1] = (size_t)&debug
;
1718 if (DT_DEBUG_INDIRECT
&& app
.dynv
[i
]==DT_DEBUG_INDIRECT
) {
1719 size_t *ptr
= (size_t *) app
.dynv
[i
+1];
1720 *ptr
= (size_t)&debug
;
1724 /* The main program must be relocated LAST since it may contin
1725 * copy relocations which depend on libraries' relocations. */
1726 reloc_all(app
.next
);
1730 if (libc
.tls_size
> sizeof builtin_tls
|| tls_align
> MIN_TLS_ALIGN
) {
1731 void *initial_tls
= calloc(libc
.tls_size
, 1);
1733 dprintf(2, "%s: Error getting %zu bytes thread-local storage: %m\n",
1734 argv
[0], libc
.tls_size
);
1737 if (__init_tp(__copy_tls(initial_tls
)) < 0) {
1741 size_t tmp_tls_size
= libc
.tls_size
;
1742 pthread_t self
= __pthread_self();
1743 /* Temporarily set the tls size to the full size of
1744 * builtin_tls so that __copy_tls will use the same layout
1745 * as it did for before. Then check, just to be safe. */
1746 libc
.tls_size
= sizeof builtin_tls
;
1747 if (__copy_tls((void*)builtin_tls
) != self
) a_crash();
1748 libc
.tls_size
= tmp_tls_size
;
1750 static_tls_cnt
= tls_cnt
;
1752 if (ldso_fail
) _exit(127);
1753 if (ldd_mode
) _exit(0);
1755 /* Determine if malloc was interposed by a replacement implementation
1756 * so that calloc and the memalign family can harden against the
1757 * possibility of incomplete replacement. */
1758 if (find_sym(head
, "malloc", 1).dso
!= &ldso
)
1759 __malloc_replaced
= 1;
1761 /* Switch to runtime mode: any further failures in the dynamic
1762 * linker are a reportable failure rather than a fatal startup
1767 debug
.bp
= dl_debug_state
;
1769 debug
.base
= ldso
.base
;
1773 if (replace_argv0
) argv
[0] = replace_argv0
;
1777 CRTJMP((void *)aux
[AT_ENTRY
], argv
-1);
1781 static void prepare_lazy(struct dso
*p
)
1783 size_t dyn
[DYN_CNT
], n
, flags1
=0;
1784 decode_vec(p
->dynv
, dyn
, DYN_CNT
);
1785 search_vec(p
->dynv
, &flags1
, DT_FLAGS_1
);
1786 if (dyn
[DT_BIND_NOW
] || (dyn
[DT_FLAGS
] & DF_BIND_NOW
) || (flags1
& DF_1_NOW
))
1788 n
= dyn
[DT_RELSZ
]/2 + dyn
[DT_RELASZ
]/3 + dyn
[DT_PLTRELSZ
]/2 + 1;
1789 if (NEED_MIPS_GOT_RELOCS
) {
1790 size_t j
=0; search_vec(p
->dynv
, &j
, DT_MIPS_GOTSYM
);
1791 size_t i
=0; search_vec(p
->dynv
, &i
, DT_MIPS_SYMTABNO
);
1794 p
->lazy
= calloc(n
, 3*sizeof(size_t));
1796 error("Error preparing lazy relocation for %s: %m", p
->name
);
1797 longjmp(*rtld_fail
, 1);
1799 p
->lazy_next
= lazy_head
;
1803 void *dlopen(const char *file
, int mode
)
1805 struct dso
*volatile p
, *orig_tail
, *orig_syms_tail
, *orig_lazy_head
, *next
;
1806 struct tls_module
*orig_tls_tail
;
1807 size_t orig_tls_cnt
, orig_tls_offset
, orig_tls_align
;
1812 if (!file
) return head
;
1814 pthread_setcancelstate(PTHREAD_CANCEL_DISABLE
, &cs
);
1815 pthread_rwlock_wrlock(&lock
);
1819 orig_tls_tail
= tls_tail
;
1820 orig_tls_cnt
= tls_cnt
;
1821 orig_tls_offset
= tls_offset
;
1822 orig_tls_align
= tls_align
;
1823 orig_lazy_head
= lazy_head
;
1824 orig_syms_tail
= syms_tail
;
1826 noload
= mode
& RTLD_NOLOAD
;
1829 if (setjmp(*rtld_fail
)) {
1830 /* Clean up anything new that was (partially) loaded */
1831 revert_syms(orig_syms_tail
);
1832 for (p
=orig_tail
->next
; p
; p
=next
) {
1834 while (p
->td_index
) {
1835 void *tmp
= p
->td_index
->next
;
1840 if (p
->rpath
!= p
->rpath_orig
)
1842 if (p
->deps
!= &nodeps_dummy
)
1847 if (!orig_tls_tail
) libc
.tls_head
= 0;
1848 tls_tail
= orig_tls_tail
;
1849 if (tls_tail
) tls_tail
->next
= 0;
1850 tls_cnt
= orig_tls_cnt
;
1851 tls_offset
= orig_tls_offset
;
1852 tls_align
= orig_tls_align
;
1853 lazy_head
= orig_lazy_head
;
1858 } else p
= load_library(file
, head
);
1862 "Library %s is not already loaded" :
1863 "Error loading shared library %s: %m",
1868 /* First load handling */
1869 int first_load
= !p
->deps
;
1872 if (!p
->relocated
&& (mode
& RTLD_LAZY
)) {
1874 for (i
=0; p
->deps
[i
]; i
++)
1875 if (!p
->deps
[i
]->relocated
)
1876 prepare_lazy(p
->deps
[i
]);
1879 if (first_load
|| (mode
& RTLD_GLOBAL
)) {
1880 /* Make new symbols global, at least temporarily, so we can do
1881 * relocations. If not RTLD_GLOBAL, this is reverted below. */
1883 for (i
=0; p
->deps
[i
]; i
++)
1884 add_syms(p
->deps
[i
]);
1890 /* If RTLD_GLOBAL was not specified, undo any new additions
1891 * to the global symbol table. This is a nop if the library was
1892 * previously loaded and already global. */
1893 if (!(mode
& RTLD_GLOBAL
))
1894 revert_syms(orig_syms_tail
);
1896 /* Processing of deferred lazy relocations must not happen until
1897 * the new libraries are committed; otherwise we could end up with
1898 * relocations resolved to symbol definitions that get removed. */
1902 if (tls_cnt
!= orig_tls_cnt
)
1909 pthread_rwlock_unlock(&lock
);
1910 if (p
) do_init_fini(orig_tail
);
1911 pthread_setcancelstate(cs
, 0);
1915 hidden
int __dl_invalid_handle(void *h
)
1918 for (p
=head
; p
; p
=p
->next
) if (h
==p
) return 0;
1919 error("Invalid library handle %p", (void *)h
);
1923 static void *addr2dso(size_t a
)
1927 if (DL_FDPIC
) for (p
=head
; p
; p
=p
->next
) {
1929 if (a
-(size_t)p
->funcdescs
< i
*sizeof(*p
->funcdescs
))
1932 for (p
=head
; p
; p
=p
->next
) {
1933 if (DL_FDPIC
&& p
->loadmap
) {
1934 for (i
=0; i
<p
->loadmap
->nsegs
; i
++) {
1935 if (a
-p
->loadmap
->segs
[i
].p_vaddr
1936 < p
->loadmap
->segs
[i
].p_memsz
)
1941 size_t phcnt
= p
->phnum
;
1942 size_t entsz
= p
->phentsize
;
1943 size_t base
= (size_t)p
->base
;
1944 for (; phcnt
--; ph
=(void *)((char *)ph
+entsz
)) {
1945 if (ph
->p_type
!= PT_LOAD
) continue;
1946 if (a
-base
-ph
->p_vaddr
< ph
->p_memsz
)
1949 if (a
-(size_t)p
->map
< p
->map_len
)
1956 static void *do_dlsym(struct dso
*p
, const char *s
, void *ra
)
1959 uint32_t h
= 0, gh
= 0, *ght
;
1961 if (p
== head
|| p
== RTLD_DEFAULT
|| p
== RTLD_NEXT
) {
1962 if (p
== RTLD_DEFAULT
) {
1964 } else if (p
== RTLD_NEXT
) {
1965 p
= addr2dso((size_t)ra
);
1969 struct symdef def
= find_sym(p
, s
, 0);
1970 if (!def
.sym
) goto failed
;
1971 if ((def
.sym
->st_info
&0xf) == STT_TLS
)
1972 return __tls_get_addr((tls_mod_off_t
[]){def
.dso
->tls_id
, def
.sym
->st_value
-DTP_OFFSET
});
1973 if (DL_FDPIC
&& (def
.sym
->st_info
&0xf) == STT_FUNC
)
1974 return def
.dso
->funcdescs
+ (def
.sym
- def
.dso
->syms
);
1975 return laddr(def
.dso
, def
.sym
->st_value
);
1977 if (__dl_invalid_handle(p
))
1979 if ((ght
= p
->ghashtab
)) {
1981 sym
= gnu_lookup(gh
, ght
, p
, s
);
1984 sym
= sysv_lookup(s
, h
, p
);
1986 if (sym
&& (sym
->st_info
&0xf) == STT_TLS
)
1987 return __tls_get_addr((tls_mod_off_t
[]){p
->tls_id
, sym
->st_value
-DTP_OFFSET
});
1988 if (DL_FDPIC
&& sym
&& sym
->st_shndx
&& (sym
->st_info
&0xf) == STT_FUNC
)
1989 return p
->funcdescs
+ (sym
- p
->syms
);
1990 if (sym
&& sym
->st_value
&& (1<<(sym
->st_info
&0xf) & OK_TYPES
))
1991 return laddr(p
, sym
->st_value
);
1992 for (i
=0; p
->deps
[i
]; i
++) {
1993 if ((ght
= p
->deps
[i
]->ghashtab
)) {
1994 if (!gh
) gh
= gnu_hash(s
);
1995 sym
= gnu_lookup(gh
, ght
, p
->deps
[i
], s
);
1997 if (!h
) h
= sysv_hash(s
);
1998 sym
= sysv_lookup(s
, h
, p
->deps
[i
]);
2000 if (sym
&& (sym
->st_info
&0xf) == STT_TLS
)
2001 return __tls_get_addr((tls_mod_off_t
[]){p
->deps
[i
]->tls_id
, sym
->st_value
-DTP_OFFSET
});
2002 if (DL_FDPIC
&& sym
&& sym
->st_shndx
&& (sym
->st_info
&0xf) == STT_FUNC
)
2003 return p
->deps
[i
]->funcdescs
+ (sym
- p
->deps
[i
]->syms
);
2004 if (sym
&& sym
->st_value
&& (1<<(sym
->st_info
&0xf) & OK_TYPES
))
2005 return laddr(p
->deps
[i
], sym
->st_value
);
2008 error("Symbol not found: %s", s
);
2012 int dladdr(const void *addr_arg
, Dl_info
*info
)
2014 size_t addr
= (size_t)addr_arg
;
2020 size_t besterr
= -1;
2022 pthread_rwlock_rdlock(&lock
);
2024 pthread_rwlock_unlock(&lock
);
2029 strings
= p
->strings
;
2030 nsym
= count_syms(p
);
2033 size_t idx
= (addr
-(size_t)p
->funcdescs
)
2034 / sizeof(*p
->funcdescs
);
2035 if (idx
< nsym
&& (sym
[idx
].st_info
&0xf) == STT_FUNC
) {
2036 best
= (size_t)(p
->funcdescs
+ idx
);
2037 bestsym
= sym
+ idx
;
2042 if (!best
) for (; nsym
; nsym
--, sym
++) {
2044 && (1<<(sym
->st_info
&0xf) & OK_TYPES
)
2045 && (1<<(sym
->st_info
>>4) & OK_BINDS
)) {
2046 size_t symaddr
= (size_t)laddr(p
, sym
->st_value
);
2047 if (symaddr
> addr
|| symaddr
<= best
)
2051 besterr
= addr
- symaddr
;
2052 if (addr
== symaddr
)
2057 if (bestsym
&& besterr
> bestsym
->st_size
-1) {
2062 info
->dli_fname
= p
->name
;
2063 info
->dli_fbase
= p
->map
;
2066 info
->dli_sname
= 0;
2067 info
->dli_saddr
= 0;
2071 if (DL_FDPIC
&& (bestsym
->st_info
&0xf) == STT_FUNC
)
2072 best
= (size_t)(p
->funcdescs
+ (bestsym
- p
->syms
));
2073 info
->dli_sname
= strings
+ bestsym
->st_name
;
2074 info
->dli_saddr
= (void *)best
;
2079 hidden
void *__dlsym(void *restrict p
, const char *restrict s
, void *restrict ra
)
2082 pthread_rwlock_rdlock(&lock
);
2083 res
= do_dlsym(p
, s
, ra
);
2084 pthread_rwlock_unlock(&lock
);
2088 int dl_iterate_phdr(int(*callback
)(struct dl_phdr_info
*info
, size_t size
, void *data
), void *data
)
2090 struct dso
*current
;
2091 struct dl_phdr_info info
;
2093 for(current
= head
; current
;) {
2094 info
.dlpi_addr
= (uintptr_t)current
->base
;
2095 info
.dlpi_name
= current
->name
;
2096 info
.dlpi_phdr
= current
->phdr
;
2097 info
.dlpi_phnum
= current
->phnum
;
2098 info
.dlpi_adds
= gencnt
;
2100 info
.dlpi_tls_modid
= current
->tls_id
;
2101 info
.dlpi_tls_data
= current
->tls
.image
;
2103 ret
= (callback
)(&info
, sizeof (info
), data
);
2105 if (ret
!= 0) break;
2107 pthread_rwlock_rdlock(&lock
);
2108 current
= current
->next
;
2109 pthread_rwlock_unlock(&lock
);
2114 static void error(const char *fmt
, ...)
2119 vdprintf(2, fmt
, ap
);
2125 __dl_vseterr(fmt
, ap
);