1 /* Load a shared object at runtime, relocate it, and run its initializer.
2 Copyright (C) 1996-2023 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
27 #include <sys/mman.h> /* Check whether MAP_COPY is defined. */
28 #include <sys/param.h>
29 #include <libc-lock.h>
31 #include <sysdep-cancel.h>
33 #include <stap-probe.h>
35 #include <libc-internal.h>
36 #include <array_length.h>
37 #include <libc-early-init.h>
38 #include <gnu/lib-names.h>
39 #include <dl-find_object.h>
45 /* We must be careful not to leave us in an inconsistent state. Thus we
46 catch any error and re-raise it after cleaning up. */
52 /* This is the caller of the dlopen() function. */
53 const void *caller_dlopen
;
58 /* Original value of _ns_global_scope_pending_adds. Set by
59 dl_open_worker. Only valid if nsid is a real namespace
61 unsigned int original_global_scope_pending_adds
;
63 /* Set to true by dl_open_worker if libc.so was already loaded into
64 the namespace at the time dl_open_worker was called. This is
65 used to determine whether libc.so early initialization has
66 already been done before, and whether to roll back the cached
67 libc_map value in the namespace in case of a dlopen failure. */
68 bool libc_already_loaded
;
70 /* Set to true if the end of dl_open_worker_begin was reached. */
73 /* Original parameters to the program and the current environment. */
79 /* Called in case the global scope cannot be extended. */
80 static void __attribute__ ((noreturn
))
81 add_to_global_resize_failure (struct link_map
*new)
83 _dl_signal_error (ENOMEM
, new->l_libname
->name
, NULL
,
84 N_ ("cannot extend global scope"));
87 /* Grow the global scope array for the namespace, so that all the new
88 global objects can be added later in add_to_global_update, without
89 risk of memory allocation failure. add_to_global_resize raises
90 exceptions for memory allocation errors. */
92 add_to_global_resize (struct link_map
*new)
94 struct link_namespaces
*ns
= &GL (dl_ns
)[new->l_ns
];
96 /* Count the objects we have to put in the global scope. */
97 unsigned int to_add
= 0;
98 for (unsigned int cnt
= 0; cnt
< new->l_searchlist
.r_nlist
; ++cnt
)
99 if (new->l_searchlist
.r_list
[cnt
]->l_global
== 0)
102 /* The symbols of the new objects and its dependencies are to be
103 introduced into the global scope that will be used to resolve
104 references from other dynamically-loaded objects.
106 The global scope is the searchlist in the main link map. We
107 extend this list if necessary. There is one problem though:
108 since this structure was allocated very early (before the libc
109 is loaded) the memory it uses is allocated by the malloc()-stub
110 in the ld.so. When we come here these functions are not used
111 anymore. Instead the malloc() implementation of the libc is
112 used. But this means the block from the main map cannot be used
113 in an realloc() call. Therefore we allocate a completely new
114 array the first time we have to add something to the locale scope. */
116 if (__builtin_add_overflow (ns
->_ns_global_scope_pending_adds
, to_add
,
117 &ns
->_ns_global_scope_pending_adds
))
118 add_to_global_resize_failure (new);
120 unsigned int new_size
= 0; /* 0 means no new allocation. */
121 void *old_global
= NULL
; /* Old allocation if free-able. */
123 /* Minimum required element count for resizing. Adjusted below for
124 an exponential resizing policy. */
125 size_t required_new_size
;
126 if (__builtin_add_overflow (ns
->_ns_main_searchlist
->r_nlist
,
127 ns
->_ns_global_scope_pending_adds
,
129 add_to_global_resize_failure (new);
131 if (ns
->_ns_global_scope_alloc
== 0)
133 if (__builtin_add_overflow (required_new_size
, 8, &new_size
))
134 add_to_global_resize_failure (new);
136 else if (required_new_size
> ns
->_ns_global_scope_alloc
)
138 if (__builtin_mul_overflow (required_new_size
, 2, &new_size
))
139 add_to_global_resize_failure (new);
141 /* The old array was allocated with our malloc, not the minimal
143 old_global
= ns
->_ns_main_searchlist
->r_list
;
148 size_t allocation_size
;
149 if (__builtin_mul_overflow (new_size
, sizeof (struct link_map
*),
151 add_to_global_resize_failure (new);
152 struct link_map
**new_global
= malloc (allocation_size
);
153 if (new_global
== NULL
)
154 add_to_global_resize_failure (new);
156 /* Copy over the old entries. */
157 memcpy (new_global
, ns
->_ns_main_searchlist
->r_list
,
158 ns
->_ns_main_searchlist
->r_nlist
* sizeof (struct link_map
*));
160 ns
->_ns_global_scope_alloc
= new_size
;
161 ns
->_ns_main_searchlist
->r_list
= new_global
;
163 if (!RTLD_SINGLE_THREAD_P
)
164 THREAD_GSCOPE_WAIT ();
170 /* Actually add the new global objects to the global scope. Must be
171 called after add_to_global_resize. This function cannot fail. */
173 add_to_global_update (struct link_map
*new)
175 struct link_namespaces
*ns
= &GL (dl_ns
)[new->l_ns
];
177 /* Now add the new entries. */
178 unsigned int new_nlist
= ns
->_ns_main_searchlist
->r_nlist
;
179 for (unsigned int cnt
= 0; cnt
< new->l_searchlist
.r_nlist
; ++cnt
)
181 struct link_map
*map
= new->l_searchlist
.r_list
[cnt
];
183 if (map
->l_global
== 0)
187 /* The array has been resized by add_to_global_resize. */
188 assert (new_nlist
< ns
->_ns_global_scope_alloc
);
190 ns
->_ns_main_searchlist
->r_list
[new_nlist
++] = map
;
192 /* We modify the global scope. Report this. */
193 if (__glibc_unlikely (GLRO(dl_debug_mask
) & DL_DEBUG_SCOPES
))
194 _dl_debug_printf ("\nadd %s [%lu] to global scope\n",
195 map
->l_name
, map
->l_ns
);
199 /* Some of the pending adds have been performed by the loop above.
200 Adjust the counter accordingly. */
201 unsigned int added
= new_nlist
- ns
->_ns_main_searchlist
->r_nlist
;
202 assert (added
<= ns
->_ns_global_scope_pending_adds
);
203 ns
->_ns_global_scope_pending_adds
-= added
;
205 atomic_write_barrier ();
206 ns
->_ns_main_searchlist
->r_nlist
= new_nlist
;
209 /* Search link maps in all namespaces for the DSO that contains the object at
210 address ADDR. Returns the pointer to the link map of the matching DSO, or
211 NULL if a match is not found. */
213 _dl_find_dso_for_object (const ElfW(Addr
) addr
)
217 /* Find the highest-addressed object that ADDR is not below. */
218 for (Lmid_t ns
= 0; ns
< GL(dl_nns
); ++ns
)
219 for (l
= GL(dl_ns
)[ns
]._ns_loaded
; l
!= NULL
; l
= l
->l_next
)
220 if (addr
>= l
->l_map_start
&& addr
< l
->l_map_end
222 || _dl_addr_inside_object (l
, (ElfW(Addr
)) addr
)))
224 assert (ns
== l
->l_ns
);
229 rtld_hidden_def (_dl_find_dso_for_object
);
231 /* Return true if NEW is found in the scope for MAP. */
233 scope_has_map (struct link_map
*map
, struct link_map
*new)
236 for (cnt
= 0; map
->l_scope
[cnt
] != NULL
; ++cnt
)
237 if (map
->l_scope
[cnt
] == &new->l_searchlist
)
242 /* Return the length of the scope for MAP. */
244 scope_size (struct link_map
*map
)
247 for (cnt
= 0; map
->l_scope
[cnt
] != NULL
; )
252 /* Resize the scopes of depended-upon objects, so that the new object
253 can be added later without further allocation of memory. This
254 function can raise an exceptions due to malloc failure. */
256 resize_scopes (struct link_map
*new)
258 /* If the file is not loaded now as a dependency, add the search
259 list of the newly loaded object to the scope. */
260 for (unsigned int i
= 0; i
< new->l_searchlist
.r_nlist
; ++i
)
262 struct link_map
*imap
= new->l_searchlist
.r_list
[i
];
264 /* If the initializer has been called already, the object has
265 not been loaded here and now. */
266 if (imap
->l_init_called
&& imap
->l_type
== lt_loaded
)
268 if (scope_has_map (imap
, new))
269 /* Avoid duplicates. */
272 size_t cnt
= scope_size (imap
);
273 if (__glibc_unlikely (cnt
+ 1 >= imap
->l_scope_max
))
275 /* The l_scope array is too small. Allocate a new one
278 struct r_scope_elem
**newp
;
280 if (imap
->l_scope
!= imap
->l_scope_mem
281 && imap
->l_scope_max
< array_length (imap
->l_scope_mem
))
283 /* If the current l_scope memory is not pointing to
284 the static memory in the structure, but the
285 static memory in the structure is large enough to
286 use for cnt + 1 scope entries, then switch to
287 using the static memory. */
288 new_size
= array_length (imap
->l_scope_mem
);
289 newp
= imap
->l_scope_mem
;
293 new_size
= imap
->l_scope_max
* 2;
294 newp
= (struct r_scope_elem
**)
295 malloc (new_size
* sizeof (struct r_scope_elem
*));
297 _dl_signal_error (ENOMEM
, "dlopen", NULL
,
298 N_("cannot create scope list"));
301 /* Copy the array and the terminating NULL. */
302 memcpy (newp
, imap
->l_scope
,
303 (cnt
+ 1) * sizeof (imap
->l_scope
[0]));
304 struct r_scope_elem
**old
= imap
->l_scope
;
306 imap
->l_scope
= newp
;
308 if (old
!= imap
->l_scope_mem
)
309 _dl_scope_free (old
);
311 imap
->l_scope_max
= new_size
;
317 /* Second stage of resize_scopes: Add NEW to the scopes. Also print
318 debugging information about scopes if requested.
320 This function cannot raise an exception because all required memory
321 has been allocated by a previous call to resize_scopes. */
323 update_scopes (struct link_map
*new)
325 for (unsigned int i
= 0; i
< new->l_searchlist
.r_nlist
; ++i
)
327 struct link_map
*imap
= new->l_searchlist
.r_list
[i
];
330 if (imap
->l_init_called
&& imap
->l_type
== lt_loaded
)
332 if (scope_has_map (imap
, new))
333 /* Avoid duplicates. */
336 size_t cnt
= scope_size (imap
);
337 /* Assert that resize_scopes has sufficiently enlarged the
339 assert (cnt
+ 1 < imap
->l_scope_max
);
341 /* First terminate the extended list. Otherwise a thread
342 might use the new last element and then use the garbage
344 imap
->l_scope
[cnt
+ 1] = NULL
;
345 atomic_write_barrier ();
346 imap
->l_scope
[cnt
] = &new->l_searchlist
;
351 /* Print scope information. */
352 if (__glibc_unlikely (GLRO(dl_debug_mask
) & DL_DEBUG_SCOPES
))
353 _dl_show_scope (imap
, from_scope
);
357 /* Call _dl_add_to_slotinfo with DO_ADD set to false, to allocate
358 space in GL (dl_tls_dtv_slotinfo_list). This can raise an
359 exception. The return value is true if any of the new objects use
362 resize_tls_slotinfo (struct link_map
*new)
364 bool any_tls
= false;
365 for (unsigned int i
= 0; i
< new->l_searchlist
.r_nlist
; ++i
)
367 struct link_map
*imap
= new->l_searchlist
.r_list
[i
];
369 /* Only add TLS memory if this object is loaded now and
370 therefore is not yet initialized. */
371 if (! imap
->l_init_called
&& imap
->l_tls_blocksize
> 0)
373 _dl_add_to_slotinfo (imap
, false);
380 /* Second stage of TLS update, after resize_tls_slotinfo. This
381 function does not raise any exception. It should only be called if
382 resize_tls_slotinfo returned true. */
384 update_tls_slotinfo (struct link_map
*new)
386 unsigned int first_static_tls
= new->l_searchlist
.r_nlist
;
387 for (unsigned int i
= 0; i
< new->l_searchlist
.r_nlist
; ++i
)
389 struct link_map
*imap
= new->l_searchlist
.r_list
[i
];
391 /* Only add TLS memory if this object is loaded now and
392 therefore is not yet initialized. */
393 if (! imap
->l_init_called
&& imap
->l_tls_blocksize
> 0)
395 _dl_add_to_slotinfo (imap
, true);
397 if (imap
->l_need_tls_init
398 && first_static_tls
== new->l_searchlist
.r_nlist
)
399 first_static_tls
= i
;
403 size_t newgen
= GL(dl_tls_generation
) + 1;
404 if (__glibc_unlikely (newgen
== 0))
405 _dl_fatal_printf (N_("\
406 TLS generation counter wrapped! Please report this."));
407 /* Can be read concurrently. */
408 atomic_store_relaxed (&GL(dl_tls_generation
), newgen
);
410 /* We need a second pass for static tls data, because
411 _dl_update_slotinfo must not be run while calls to
412 _dl_add_to_slotinfo are still pending. */
413 for (unsigned int i
= first_static_tls
; i
< new->l_searchlist
.r_nlist
; ++i
)
415 struct link_map
*imap
= new->l_searchlist
.r_list
[i
];
417 if (imap
->l_need_tls_init
418 && ! imap
->l_init_called
419 && imap
->l_tls_blocksize
> 0)
421 /* For static TLS we have to allocate the memory here and
422 now, but we can delay updating the DTV. */
423 imap
->l_need_tls_init
= 0;
425 /* Update the slot information data for at least the
426 generation of the DSO we are allocating data for. */
428 /* FIXME: This can terminate the process on memory
429 allocation failure. It is not possible to raise
430 exceptions from this context; to fix this bug,
431 _dl_update_slotinfo would have to be split into two
432 operations, similar to resize_scopes and update_scopes
433 above. This is related to bug 16134. */
434 _dl_update_slotinfo (imap
->l_tls_modid
);
437 dl_init_static_tls (imap
);
438 assert (imap
->l_need_tls_init
== 0);
443 /* Mark the objects as NODELETE if required. This is delayed until
444 after dlopen failure is not possible, so that _dl_close can clean
445 up objects if necessary. */
447 activate_nodelete (struct link_map
*new)
449 /* It is necessary to traverse the entire namespace. References to
450 objects in the global scope and unique symbol bindings can force
451 NODELETE status for objects outside the local scope. */
452 for (struct link_map
*l
= GL (dl_ns
)[new->l_ns
]._ns_loaded
; l
!= NULL
;
454 if (l
->l_nodelete_pending
)
456 if (__glibc_unlikely (GLRO (dl_debug_mask
) & DL_DEBUG_FILES
))
457 _dl_debug_printf ("activating NODELETE for %s [%lu]\n",
460 /* The flag can already be true at this point, e.g. a signal
461 handler may have triggered lazy binding and set NODELETE
462 status immediately. */
463 l
->l_nodelete_active
= true;
465 /* This is just a debugging aid, to indicate that
466 activate_nodelete has run for this map. */
467 l
->l_nodelete_pending
= false;
471 /* struct dl_init_args and call_dl_init are used to call _dl_init with
472 exception handling disabled. */
475 struct link_map
*new;
482 call_dl_init (void *closure
)
484 struct dl_init_args
*args
= closure
;
485 _dl_init (args
->new, args
->argc
, args
->argv
, args
->env
);
489 dl_open_worker_begin (void *a
)
491 struct dl_open_args
*args
= a
;
492 const char *file
= args
->file
;
493 int mode
= args
->mode
;
494 struct link_map
*call_map
= NULL
;
496 /* Determine the caller's map if necessary. This is needed in case
497 we have a DST, when we don't know the namespace ID we have to put
498 the new object in, or when the file name has no path in which
499 case we need to look along the RUNPATH/RPATH of the caller. */
500 const char *dst
= strchr (file
, '$');
501 if (dst
!= NULL
|| args
->nsid
== __LM_ID_CALLER
502 || strchr (file
, '/') == NULL
)
504 const void *caller_dlopen
= args
->caller_dlopen
;
506 /* We have to find out from which object the caller is calling.
507 By default we assume this is the main application. */
508 call_map
= GL(dl_ns
)[LM_ID_BASE
]._ns_loaded
;
510 struct link_map
*l
= _dl_find_dso_for_object ((ElfW(Addr
)) caller_dlopen
);
515 if (args
->nsid
== __LM_ID_CALLER
)
516 args
->nsid
= call_map
->l_ns
;
519 /* The namespace ID is now known. Keep track of whether libc.so was
520 already loaded, to determine whether it is necessary to call the
521 early initialization routine (or clear libc_map on error). */
522 args
->libc_already_loaded
= GL(dl_ns
)[args
->nsid
].libc_map
!= NULL
;
524 /* Retain the old value, so that it can be restored. */
525 args
->original_global_scope_pending_adds
526 = GL (dl_ns
)[args
->nsid
]._ns_global_scope_pending_adds
;
528 /* One might be tempted to assert that we are RT_CONSISTENT at this point, but that
529 may not be true if this is a recursive call to dlopen. */
530 _dl_debug_initialize (0, args
->nsid
);
532 /* Load the named object. */
533 struct link_map
*new;
534 args
->map
= new = _dl_map_object (call_map
, file
, lt_loaded
, 0,
535 mode
| __RTLD_CALLMAP
, args
->nsid
);
537 /* If the pointer returned is NULL this means the RTLD_NOLOAD flag is
538 set and the object is not already loaded. */
541 assert (mode
& RTLD_NOLOAD
);
545 if (__glibc_unlikely (mode
& __RTLD_SPROF
))
546 /* This happens only if we load a DSO for 'sprof'. */
549 /* This object is directly loaded. */
550 ++new->l_direct_opencount
;
552 /* It was already open. */
553 if (__glibc_unlikely (new->l_searchlist
.r_list
!= NULL
))
555 /* Let the user know about the opencount. */
556 if (__glibc_unlikely (GLRO(dl_debug_mask
) & DL_DEBUG_FILES
))
557 _dl_debug_printf ("opening file=%s [%lu]; direct_opencount=%u\n\n",
558 new->l_name
, new->l_ns
, new->l_direct_opencount
);
560 /* If the user requested the object to be in the global
561 namespace but it is not so far, prepare to add it now. This
562 can raise an exception to do a malloc failure. */
563 if ((mode
& RTLD_GLOBAL
) && new->l_global
== 0)
564 add_to_global_resize (new);
566 /* Mark the object as not deletable if the RTLD_NODELETE flags
568 if (__glibc_unlikely (mode
& RTLD_NODELETE
))
570 if (__glibc_unlikely (GLRO (dl_debug_mask
) & DL_DEBUG_FILES
)
571 && !new->l_nodelete_active
)
572 _dl_debug_printf ("marking %s [%lu] as NODELETE\n",
573 new->l_name
, new->l_ns
);
574 new->l_nodelete_active
= true;
577 /* Finalize the addition to the global scope. */
578 if ((mode
& RTLD_GLOBAL
) && new->l_global
== 0)
579 add_to_global_update (new);
581 const int r_state
__attribute__ ((unused
))
582 = _dl_debug_update (args
->nsid
)->r_state
;
583 assert (r_state
== RT_CONSISTENT
);
588 /* Schedule NODELETE marking for the directly loaded object if
590 if (__glibc_unlikely (mode
& RTLD_NODELETE
))
591 new->l_nodelete_pending
= true;
593 /* Load that object's dependencies. */
594 _dl_map_object_deps (new, NULL
, 0, 0,
595 mode
& (__RTLD_DLOPEN
| RTLD_DEEPBIND
| __RTLD_AUDIT
));
597 /* So far, so good. Now check the versions. */
598 for (unsigned int i
= 0; i
< new->l_searchlist
.r_nlist
; ++i
)
599 if (new->l_searchlist
.r_list
[i
]->l_real
->l_versions
== NULL
)
601 struct link_map
*map
= new->l_searchlist
.r_list
[i
]->l_real
;
602 _dl_check_map_versions (map
, 0, 0);
604 /* During static dlopen, check if ld.so has been loaded.
605 Perform partial initialization in this case. This must
606 come after the symbol versioning initialization in
607 _dl_check_map_versions. */
608 if (map
->l_info
[DT_SONAME
] != NULL
609 && strcmp (((const char *) D_PTR (map
, l_info
[DT_STRTAB
])
610 + map
->l_info
[DT_SONAME
]->d_un
.d_val
), LD_SO
) == 0)
611 __rtld_static_init (map
);
616 /* Auditing checkpoint: we have added all objects. */
617 _dl_audit_activity_nsid (new->l_ns
, LA_ACT_CONSISTENT
);
620 /* Notify the debugger all new objects are now ready to go. */
621 struct r_debug
*r
= _dl_debug_update (args
->nsid
);
622 r
->r_state
= RT_CONSISTENT
;
624 LIBC_PROBE (map_complete
, 3, args
->nsid
, r
, new);
626 _dl_open_check (new);
628 /* Print scope information. */
629 if (__glibc_unlikely (GLRO(dl_debug_mask
) & DL_DEBUG_SCOPES
))
630 _dl_show_scope (new, 0);
632 /* Only do lazy relocation if `LD_BIND_NOW' is not set. */
633 int reloc_mode
= mode
& __RTLD_AUDIT
;
635 reloc_mode
|= mode
& RTLD_LAZY
;
637 /* Objects must be sorted by dependency for the relocation process.
638 This allows IFUNC relocations to work and it also means copy
639 relocation of dependencies are if necessary overwritten.
640 __dl_map_object_deps has already sorted l_initfini for us. */
641 unsigned int first
= UINT_MAX
;
642 unsigned int last
= 0;
644 struct link_map
*l
= new->l_initfini
[0];
647 if (! l
->l_real
->l_relocated
)
649 if (first
== UINT_MAX
)
653 l
= new->l_initfini
[++j
];
657 int relocation_in_progress
= 0;
659 /* Perform relocation. This can trigger lazy binding in IFUNC
660 resolvers. For NODELETE mappings, these dependencies are not
661 recorded because the flag has not been applied to the newly
662 loaded objects. This means that upon dlopen failure, these
663 NODELETE objects can be unloaded despite existing references to
664 them. However, such relocation dependencies in IFUNC resolvers
665 are undefined anyway, so this is not a problem. */
667 for (unsigned int i
= last
; i
-- > first
; )
669 l
= new->l_initfini
[i
];
671 if (l
->l_real
->l_relocated
)
674 if (! relocation_in_progress
)
676 /* Notify the debugger that relocations are about to happen. */
677 LIBC_PROBE (reloc_start
, 2, args
->nsid
, r
);
678 relocation_in_progress
= 1;
682 if (__glibc_unlikely (GLRO(dl_profile
) != NULL
))
684 /* If this here is the shared object which we want to profile
685 make sure the profile is started. We can find out whether
686 this is necessary or not by observing the `_dl_profile_map'
687 variable. If it was NULL but is not NULL afterwards we must
688 start the profiling. */
689 struct link_map
*old_profile_map
= GL(dl_profile_map
);
691 _dl_relocate_object (l
, l
->l_scope
, reloc_mode
| RTLD_LAZY
, 1);
693 if (old_profile_map
== NULL
&& GL(dl_profile_map
) != NULL
)
695 /* We must prepare the profiling. */
696 _dl_start_profile ();
698 /* Prevent unloading the object. */
699 GL(dl_profile_map
)->l_nodelete_active
= true;
704 _dl_relocate_object (l
, l
->l_scope
, reloc_mode
, 0);
707 /* This only performs the memory allocations. The actual update of
708 the scopes happens below, after failure is impossible. */
711 /* Increase the size of the GL (dl_tls_dtv_slotinfo_list) data
713 bool any_tls
= resize_tls_slotinfo (new);
715 /* Perform the necessary allocations for adding new global objects
716 to the global scope below. */
717 if (mode
& RTLD_GLOBAL
)
718 add_to_global_resize (new);
720 /* Demarcation point: After this, no recoverable errors are allowed.
721 All memory allocations for new objects must have happened
724 /* Finalize the NODELETE status first. This comes before
725 update_scopes, so that lazy binding will not see pending NODELETE
726 state for newly loaded objects. There is a compiler barrier in
727 update_scopes which ensures that the changes from
728 activate_nodelete are visible before new objects show up in the
730 activate_nodelete (new);
732 /* Second stage after resize_scopes: Actually perform the scope
733 update. After this, dlsym and lazy binding can bind to new
737 if (!_dl_find_object_update (new))
738 _dl_signal_error (ENOMEM
, new->l_libname
->name
, NULL
,
739 N_ ("cannot allocate address lookup data"));
741 /* FIXME: It is unclear whether the order here is correct.
742 Shouldn't new objects be made available for binding (and thus
743 execution) only after there TLS data has been set up fully?
744 Fixing bug 16134 will likely make this distinction less
747 /* Second stage after resize_tls_slotinfo: Update the slotinfo data
750 /* FIXME: This calls _dl_update_slotinfo, which aborts the process
751 on memory allocation failure. See bug 16134. */
752 update_tls_slotinfo (new);
754 /* Notify the debugger all new objects have been relocated. */
755 if (relocation_in_progress
)
756 LIBC_PROBE (reloc_complete
, 3, args
->nsid
, r
, new);
758 /* If libc.so was not there before, attempt to call its early
759 initialization routine. Indicate to the initialization routine
760 whether the libc being initialized is the one in the base
762 if (!args
->libc_already_loaded
)
764 /* dlopen cannot be used to load an initial libc by design. */
765 struct link_map
*libc_map
= GL(dl_ns
)[args
->nsid
].libc_map
;
766 _dl_call_libc_early_init (libc_map
, false);
769 args
->worker_continue
= true;
773 dl_open_worker (void *a
)
775 struct dl_open_args
*args
= a
;
777 args
->worker_continue
= false;
780 /* Protects global and module specific TLS state. */
781 __rtld_lock_lock_recursive (GL(dl_load_tls_lock
));
783 struct dl_exception ex
;
784 int err
= _dl_catch_exception (&ex
, dl_open_worker_begin
, args
);
786 __rtld_lock_unlock_recursive (GL(dl_load_tls_lock
));
788 if (__glibc_unlikely (ex
.errstring
!= NULL
))
789 /* Reraise the error. */
790 _dl_signal_exception (err
, &ex
, NULL
);
793 if (!args
->worker_continue
)
796 int mode
= args
->mode
;
797 struct link_map
*new = args
->map
;
799 /* Run the initializer functions of new objects. Temporarily
800 disable the exception handler, so that lazy binding failures are
803 struct dl_init_args init_args
=
810 _dl_catch_exception (NULL
, call_dl_init
, &init_args
);
813 /* Now we can make the new map available in the global scope. */
814 if (mode
& RTLD_GLOBAL
)
815 add_to_global_update (new);
817 /* Let the user know about the opencount. */
818 if (__glibc_unlikely (GLRO(dl_debug_mask
) & DL_DEBUG_FILES
))
819 _dl_debug_printf ("opening file=%s [%lu]; direct_opencount=%u\n\n",
820 new->l_name
, new->l_ns
, new->l_direct_opencount
);
824 _dl_open (const char *file
, int mode
, const void *caller_dlopen
, Lmid_t nsid
,
825 int argc
, char *argv
[], char *env
[])
827 if ((mode
& RTLD_BINDING_MASK
) == 0)
828 /* One of the flags must be set. */
829 _dl_signal_error (EINVAL
, file
, NULL
, N_("invalid mode for dlopen()"));
831 /* Make sure we are alone. */
832 __rtld_lock_lock_recursive (GL(dl_load_lock
));
834 if (__glibc_unlikely (nsid
== LM_ID_NEWLM
))
836 /* Find a new namespace. */
837 for (nsid
= 1; DL_NNS
> 1 && nsid
< GL(dl_nns
); ++nsid
)
838 if (GL(dl_ns
)[nsid
]._ns_loaded
== NULL
)
841 if (__glibc_unlikely (nsid
== DL_NNS
))
843 /* No more namespace available. */
844 __rtld_lock_unlock_recursive (GL(dl_load_lock
));
846 _dl_signal_error (EINVAL
, file
, NULL
, N_("\
847 no more namespaces available for dlmopen()"));
849 else if (nsid
== GL(dl_nns
))
851 __rtld_lock_initialize (GL(dl_ns
)[nsid
]._ns_unique_sym_table
.lock
);
855 GL(dl_ns
)[nsid
].libc_map
= NULL
;
856 _dl_debug_update (nsid
)->r_state
= RT_CONSISTENT
;
858 /* Never allow loading a DSO in a namespace which is empty. Such
859 direct placements is only causing problems. Also don't allow
860 loading into a namespace used for auditing. */
861 else if (__glibc_unlikely (nsid
!= LM_ID_BASE
&& nsid
!= __LM_ID_CALLER
)
862 && (__glibc_unlikely (nsid
< 0 || nsid
>= GL(dl_nns
))
863 /* This prevents the [NSID] index expressions from being
864 evaluated, so the compiler won't think that we are
865 accessing an invalid index here in the !SHARED case where
866 DL_NNS is 1 and so any NSID != 0 is invalid. */
868 || GL(dl_ns
)[nsid
]._ns_nloaded
== 0
869 || GL(dl_ns
)[nsid
]._ns_loaded
->l_auditing
))
870 _dl_signal_error (EINVAL
, file
, NULL
,
871 N_("invalid target namespace in dlmopen()"));
873 struct dl_open_args args
;
876 args
.caller_dlopen
= caller_dlopen
;
879 /* args.libc_already_loaded is always assigned by dl_open_worker
880 (before any explicit/non-local returns). */
885 struct dl_exception exception
;
886 int errcode
= _dl_catch_exception (&exception
, dl_open_worker
, &args
);
888 #if defined USE_LDCONFIG && !defined MAP_COPY
889 /* We must unmap the cache file. */
893 /* Do this for both the error and success cases. The old value has
894 only been determined if the namespace ID was assigned (i.e., it
895 is not __LM_ID_CALLER). In the success case, we actually may
896 have consumed more pending adds than planned (because the local
897 scopes overlap in case of a recursive dlopen, the inner dlopen
898 doing some of the globalization work of the outer dlopen), so the
899 old pending adds value is larger than absolutely necessary.
900 Since it is just a conservative upper bound, this is harmless.
901 The top-level dlopen call will restore the field to zero. */
903 GL (dl_ns
)[args
.nsid
]._ns_global_scope_pending_adds
904 = args
.original_global_scope_pending_adds
;
906 /* See if an error occurred during loading. */
907 if (__glibc_unlikely (exception
.errstring
!= NULL
))
909 /* Avoid keeping around a dangling reference to the libc.so link
910 map in case it has been cached in libc_map. */
911 if (!args
.libc_already_loaded
)
912 GL(dl_ns
)[args
.nsid
].libc_map
= NULL
;
914 /* Remove the object from memory. It may be in an inconsistent
915 state if relocation failed, for example. */
918 _dl_close_worker (args
.map
, true);
920 /* All l_nodelete_pending objects should have been deleted
921 at this point, which is why it is not necessary to reset
925 /* Release the lock. */
926 __rtld_lock_unlock_recursive (GL(dl_load_lock
));
928 /* Reraise the error. */
929 _dl_signal_exception (errcode
, &exception
, NULL
);
932 const int r_state
__attribute__ ((unused
))
933 = _dl_debug_update (args
.nsid
)->r_state
;
934 assert (r_state
== RT_CONSISTENT
);
936 /* Release the lock. */
937 __rtld_lock_unlock_recursive (GL(dl_load_lock
));
944 _dl_show_scope (struct link_map
*l
, int from
)
946 _dl_debug_printf ("object=%s [%lu]\n",
947 DSO_FILENAME (l
->l_name
), l
->l_ns
);
948 if (l
->l_scope
!= NULL
)
949 for (int scope_cnt
= from
; l
->l_scope
[scope_cnt
] != NULL
; ++scope_cnt
)
951 _dl_debug_printf (" scope %u:", scope_cnt
);
953 for (unsigned int cnt
= 0; cnt
< l
->l_scope
[scope_cnt
]->r_nlist
; ++cnt
)
954 if (*l
->l_scope
[scope_cnt
]->r_list
[cnt
]->l_name
)
955 _dl_debug_printf_c (" %s",
956 l
->l_scope
[scope_cnt
]->r_list
[cnt
]->l_name
);
958 _dl_debug_printf_c (" %s", RTLD_PROGNAME
);
960 _dl_debug_printf_c ("\n");
963 _dl_debug_printf (" no scope\n");
964 _dl_debug_printf ("\n");