(open_verify): Find .note.ABI-tag notes even in PT_NOTE segments with multiple notes.
[glibc.git] / elf / dl-load.c
blob73e9b9ce7b12f7aff1fd62fe4377a1feef5fca49
1 /* Map in a shared object's segments from the file.
2 Copyright (C) 1995-2005, 2006, 2007 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, write to the Free
17 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
18 02111-1307 USA. */
20 #include <elf.h>
21 #include <errno.h>
22 #include <fcntl.h>
23 #include <libintl.h>
24 #include <stdbool.h>
25 #include <stdlib.h>
26 #include <string.h>
27 #include <unistd.h>
28 #include <ldsodefs.h>
29 #include <bits/wordsize.h>
30 #include <sys/mman.h>
31 #include <sys/param.h>
32 #include <sys/stat.h>
33 #include <sys/types.h>
34 #include "dynamic-link.h"
35 #include <abi-tag.h>
36 #include <stackinfo.h>
37 #include <caller.h>
38 #include <sysdep.h>
40 #include <dl-dst.h>
42 /* On some systems, no flag bits are given to specify file mapping. */
43 #ifndef MAP_FILE
44 # define MAP_FILE 0
45 #endif
47 /* The right way to map in the shared library files is MAP_COPY, which
48 makes a virtual copy of the data at the time of the mmap call; this
49 guarantees the mapped pages will be consistent even if the file is
50 overwritten. Some losing VM systems like Linux's lack MAP_COPY. All we
51 get is MAP_PRIVATE, which copies each page when it is modified; this
52 means if the file is overwritten, we may at some point get some pages
53 from the new version after starting with pages from the old version.
55 To make up for the lack and avoid the overwriting problem,
56 what Linux does have is MAP_DENYWRITE. This prevents anyone
57 from modifying the file while we have it mapped. */
58 #ifndef MAP_COPY
59 # ifdef MAP_DENYWRITE
60 # define MAP_COPY (MAP_PRIVATE | MAP_DENYWRITE)
61 # else
62 # define MAP_COPY MAP_PRIVATE
63 # endif
64 #endif
66 /* Some systems link their relocatable objects for another base address
67 than 0. We want to know the base address for these such that we can
68 subtract this address from the segment addresses during mapping.
69 This results in a more efficient address space usage. Defaults to
70 zero for almost all systems. */
71 #ifndef MAP_BASE_ADDR
72 # define MAP_BASE_ADDR(l) 0
73 #endif
76 #include <endian.h>
77 #if BYTE_ORDER == BIG_ENDIAN
78 # define byteorder ELFDATA2MSB
79 #elif BYTE_ORDER == LITTLE_ENDIAN
80 # define byteorder ELFDATA2LSB
81 #else
82 # error "Unknown BYTE_ORDER " BYTE_ORDER
83 # define byteorder ELFDATANONE
84 #endif
86 #define STRING(x) __STRING (x)
88 #ifdef MAP_ANON
89 /* The fd is not examined when using MAP_ANON. */
90 # define ANONFD -1
91 #else
92 int _dl_zerofd = -1;
93 # define ANONFD _dl_zerofd
94 #endif
96 /* Handle situations where we have a preferred location in memory for
97 the shared objects. */
98 #ifdef ELF_PREFERRED_ADDRESS_DATA
99 ELF_PREFERRED_ADDRESS_DATA;
100 #endif
101 #ifndef ELF_PREFERRED_ADDRESS
102 # define ELF_PREFERRED_ADDRESS(loader, maplength, mapstartpref) (mapstartpref)
103 #endif
104 #ifndef ELF_FIXED_ADDRESS
105 # define ELF_FIXED_ADDRESS(loader, mapstart) ((void) 0)
106 #endif
109 int __stack_prot attribute_hidden attribute_relro
110 #if _STACK_GROWS_DOWN && defined PROT_GROWSDOWN
111 = PROT_GROWSDOWN;
112 #elif _STACK_GROWS_UP && defined PROT_GROWSUP
113 = PROT_GROWSUP;
114 #else
115 = 0;
116 #endif
119 /* Type for the buffer we put the ELF header and hopefully the program
120 header. This buffer does not really have to be too large. In most
121 cases the program header follows the ELF header directly. If this
122 is not the case all bets are off and we can make the header
123 arbitrarily large and still won't get it read. This means the only
124 question is how large are the ELF and program header combined. The
125 ELF header 32-bit files is 52 bytes long and in 64-bit files is 64
126 bytes long. Each program header entry is again 32 and 56 bytes
127 long respectively. I.e., even with a file which has 10 program
128 header entries we only have to read 372B/624B respectively. Add to
129 this a bit of margin for program notes and reading 512B and 832B
130 for 32-bit and 64-bit files respecitvely is enough. If this
131 heuristic should really fail for some file the code in
132 `_dl_map_object_from_fd' knows how to recover. */
133 struct filebuf
135 ssize_t len;
136 #if __WORDSIZE == 32
137 # define FILEBUF_SIZE 512
138 #else
139 # define FILEBUF_SIZE 832
140 #endif
141 char buf[FILEBUF_SIZE] __attribute__ ((aligned (__alignof (ElfW(Ehdr)))));
144 /* This is the decomposed LD_LIBRARY_PATH search path. */
145 static struct r_search_path_struct env_path_list attribute_relro;
147 /* List of the hardware capabilities we might end up using. */
148 static const struct r_strlenpair *capstr attribute_relro;
149 static size_t ncapstr attribute_relro;
150 static size_t max_capstrlen attribute_relro;
153 /* Get the generated information about the trusted directories. */
154 #include "trusted-dirs.h"
156 static const char system_dirs[] = SYSTEM_DIRS;
157 static const size_t system_dirs_len[] =
159 SYSTEM_DIRS_LEN
161 #define nsystem_dirs_len \
162 (sizeof (system_dirs_len) / sizeof (system_dirs_len[0]))
165 /* Local version of `strdup' function. */
166 static inline char *
167 local_strdup (const char *s)
169 size_t len = strlen (s) + 1;
170 void *new = malloc (len);
172 if (new == NULL)
173 return NULL;
175 return (char *) memcpy (new, s, len);
179 static size_t
180 is_dst (const char *start, const char *name, const char *str,
181 int is_path, int secure)
183 size_t len;
184 bool is_curly = false;
186 if (name[0] == '{')
188 is_curly = true;
189 ++name;
192 len = 0;
193 while (name[len] == str[len] && name[len] != '\0')
194 ++len;
196 if (is_curly)
198 if (name[len] != '}')
199 return 0;
201 /* Point again at the beginning of the name. */
202 --name;
203 /* Skip over closing curly brace and adjust for the --name. */
204 len += 2;
206 else if (name[len] != '\0' && name[len] != '/'
207 && (!is_path || name[len] != ':'))
208 return 0;
210 if (__builtin_expect (secure, 0)
211 && ((name[len] != '\0' && (!is_path || name[len] != ':'))
212 || (name != start + 1 && (!is_path || name[-2] != ':'))))
213 return 0;
215 return len;
219 size_t
220 _dl_dst_count (const char *name, int is_path)
222 const char *const start = name;
223 size_t cnt = 0;
227 size_t len;
229 /* $ORIGIN is not expanded for SUID/GUID programs (except if it
230 is $ORIGIN alone) and it must always appear first in path. */
231 ++name;
232 if ((len = is_dst (start, name, "ORIGIN", is_path,
233 INTUSE(__libc_enable_secure))) != 0
234 || (len = is_dst (start, name, "PLATFORM", is_path, 0)) != 0
235 || (len = is_dst (start, name, "LIB", is_path, 0)) != 0)
236 ++cnt;
238 name = strchr (name + len, '$');
240 while (name != NULL);
242 return cnt;
246 char *
247 _dl_dst_substitute (struct link_map *l, const char *name, char *result,
248 int is_path)
250 const char *const start = name;
251 char *last_elem, *wp;
253 /* Now fill the result path. While copying over the string we keep
254 track of the start of the last path element. When we come accross
255 a DST we copy over the value or (if the value is not available)
256 leave the entire path element out. */
257 last_elem = wp = result;
261 if (__builtin_expect (*name == '$', 0))
263 const char *repl = NULL;
264 size_t len;
266 ++name;
267 if ((len = is_dst (start, name, "ORIGIN", is_path,
268 INTUSE(__libc_enable_secure))) != 0)
270 #ifndef SHARED
271 if (l == NULL)
272 repl = _dl_get_origin ();
273 else
274 #endif
275 repl = l->l_origin;
277 else if ((len = is_dst (start, name, "PLATFORM", is_path, 0)) != 0)
278 repl = GLRO(dl_platform);
279 else if ((len = is_dst (start, name, "LIB", is_path, 0)) != 0)
280 repl = DL_DST_LIB;
282 if (repl != NULL && repl != (const char *) -1)
284 wp = __stpcpy (wp, repl);
285 name += len;
287 else if (len > 1)
289 /* We cannot use this path element, the value of the
290 replacement is unknown. */
291 wp = last_elem;
292 name += len;
293 while (*name != '\0' && (!is_path || *name != ':'))
294 ++name;
296 else
297 /* No DST we recognize. */
298 *wp++ = '$';
300 else
302 *wp++ = *name++;
303 if (is_path && *name == ':')
304 last_elem = wp;
307 while (*name != '\0');
309 *wp = '\0';
311 return result;
315 /* Return copy of argument with all recognized dynamic string tokens
316 ($ORIGIN and $PLATFORM for now) replaced. On some platforms it
317 might not be possible to determine the path from which the object
318 belonging to the map is loaded. In this case the path element
319 containing $ORIGIN is left out. */
320 static char *
321 expand_dynamic_string_token (struct link_map *l, const char *s)
323 /* We make two runs over the string. First we determine how large the
324 resulting string is and then we copy it over. Since this is now
325 frequently executed operation we are looking here not for performance
326 but rather for code size. */
327 size_t cnt;
328 size_t total;
329 char *result;
331 /* Determine the number of DST elements. */
332 cnt = DL_DST_COUNT (s, 1);
334 /* If we do not have to replace anything simply copy the string. */
335 if (__builtin_expect (cnt, 0) == 0)
336 return local_strdup (s);
338 /* Determine the length of the substituted string. */
339 total = DL_DST_REQUIRED (l, s, strlen (s), cnt);
341 /* Allocate the necessary memory. */
342 result = (char *) malloc (total + 1);
343 if (result == NULL)
344 return NULL;
346 return _dl_dst_substitute (l, s, result, 1);
350 /* Add `name' to the list of names for a particular shared object.
351 `name' is expected to have been allocated with malloc and will
352 be freed if the shared object already has this name.
353 Returns false if the object already had this name. */
354 static void
355 internal_function
356 add_name_to_object (struct link_map *l, const char *name)
358 struct libname_list *lnp, *lastp;
359 struct libname_list *newname;
360 size_t name_len;
362 lastp = NULL;
363 for (lnp = l->l_libname; lnp != NULL; lastp = lnp, lnp = lnp->next)
364 if (strcmp (name, lnp->name) == 0)
365 return;
367 name_len = strlen (name) + 1;
368 newname = (struct libname_list *) malloc (sizeof *newname + name_len);
369 if (newname == NULL)
371 /* No more memory. */
372 _dl_signal_error (ENOMEM, name, NULL, N_("cannot allocate name record"));
373 return;
375 /* The object should have a libname set from _dl_new_object. */
376 assert (lastp != NULL);
378 newname->name = memcpy (newname + 1, name, name_len);
379 newname->next = NULL;
380 newname->dont_free = 0;
381 lastp->next = newname;
384 /* Standard search directories. */
385 static struct r_search_path_struct rtld_search_dirs attribute_relro;
387 static size_t max_dirnamelen;
389 static struct r_search_path_elem **
390 fillin_rpath (char *rpath, struct r_search_path_elem **result, const char *sep,
391 int check_trusted, const char *what, const char *where)
393 char *cp;
394 size_t nelems = 0;
396 while ((cp = __strsep (&rpath, sep)) != NULL)
398 struct r_search_path_elem *dirp;
399 size_t len = strlen (cp);
401 /* `strsep' can pass an empty string. This has to be
402 interpreted as `use the current directory'. */
403 if (len == 0)
405 static const char curwd[] = "./";
406 cp = (char *) curwd;
409 /* Remove trailing slashes (except for "/"). */
410 while (len > 1 && cp[len - 1] == '/')
411 --len;
413 /* Now add one if there is none so far. */
414 if (len > 0 && cp[len - 1] != '/')
415 cp[len++] = '/';
417 /* Make sure we don't use untrusted directories if we run SUID. */
418 if (__builtin_expect (check_trusted, 0))
420 const char *trun = system_dirs;
421 size_t idx;
422 int unsecure = 1;
424 /* All trusted directories must be complete names. */
425 if (cp[0] == '/')
427 for (idx = 0; idx < nsystem_dirs_len; ++idx)
429 if (len == system_dirs_len[idx]
430 && memcmp (trun, cp, len) == 0)
432 /* Found it. */
433 unsecure = 0;
434 break;
437 trun += system_dirs_len[idx] + 1;
441 if (unsecure)
442 /* Simply drop this directory. */
443 continue;
446 /* See if this directory is already known. */
447 for (dirp = GL(dl_all_dirs); dirp != NULL; dirp = dirp->next)
448 if (dirp->dirnamelen == len && memcmp (cp, dirp->dirname, len) == 0)
449 break;
451 if (dirp != NULL)
453 /* It is available, see whether it's on our own list. */
454 size_t cnt;
455 for (cnt = 0; cnt < nelems; ++cnt)
456 if (result[cnt] == dirp)
457 break;
459 if (cnt == nelems)
460 result[nelems++] = dirp;
462 else
464 size_t cnt;
465 enum r_dir_status init_val;
466 size_t where_len = where ? strlen (where) + 1 : 0;
468 /* It's a new directory. Create an entry and add it. */
469 dirp = (struct r_search_path_elem *)
470 malloc (sizeof (*dirp) + ncapstr * sizeof (enum r_dir_status)
471 + where_len + len + 1);
472 if (dirp == NULL)
473 _dl_signal_error (ENOMEM, NULL, NULL,
474 N_("cannot create cache for search path"));
476 dirp->dirname = ((char *) dirp + sizeof (*dirp)
477 + ncapstr * sizeof (enum r_dir_status));
478 *((char *) __mempcpy ((char *) dirp->dirname, cp, len)) = '\0';
479 dirp->dirnamelen = len;
481 if (len > max_dirnamelen)
482 max_dirnamelen = len;
484 /* We have to make sure all the relative directories are
485 never ignored. The current directory might change and
486 all our saved information would be void. */
487 init_val = cp[0] != '/' ? existing : unknown;
488 for (cnt = 0; cnt < ncapstr; ++cnt)
489 dirp->status[cnt] = init_val;
491 dirp->what = what;
492 if (__builtin_expect (where != NULL, 1))
493 dirp->where = memcpy ((char *) dirp + sizeof (*dirp) + len + 1
494 + (ncapstr * sizeof (enum r_dir_status)),
495 where, where_len);
496 else
497 dirp->where = NULL;
499 dirp->next = GL(dl_all_dirs);
500 GL(dl_all_dirs) = dirp;
502 /* Put it in the result array. */
503 result[nelems++] = dirp;
507 /* Terminate the array. */
508 result[nelems] = NULL;
510 return result;
514 static bool
515 internal_function
516 decompose_rpath (struct r_search_path_struct *sps,
517 const char *rpath, struct link_map *l, const char *what)
519 /* Make a copy we can work with. */
520 const char *where = l->l_name;
521 char *copy;
522 char *cp;
523 struct r_search_path_elem **result;
524 size_t nelems;
525 /* Initialize to please the compiler. */
526 const char *errstring = NULL;
528 /* First see whether we must forget the RUNPATH and RPATH from this
529 object. */
530 if (__builtin_expect (GLRO(dl_inhibit_rpath) != NULL, 0)
531 && !INTUSE(__libc_enable_secure))
533 const char *inhp = GLRO(dl_inhibit_rpath);
537 const char *wp = where;
539 while (*inhp == *wp && *wp != '\0')
541 ++inhp;
542 ++wp;
545 if (*wp == '\0' && (*inhp == '\0' || *inhp == ':'))
547 /* This object is on the list of objects for which the
548 RUNPATH and RPATH must not be used. */
549 sps->dirs = (void *) -1;
550 return false;
553 while (*inhp != '\0')
554 if (*inhp++ == ':')
555 break;
557 while (*inhp != '\0');
560 /* Make a writable copy. At the same time expand possible dynamic
561 string tokens. */
562 copy = expand_dynamic_string_token (l, rpath);
563 if (copy == NULL)
565 errstring = N_("cannot create RUNPATH/RPATH copy");
566 goto signal_error;
569 /* Count the number of necessary elements in the result array. */
570 nelems = 0;
571 for (cp = copy; *cp != '\0'; ++cp)
572 if (*cp == ':')
573 ++nelems;
575 /* Allocate room for the result. NELEMS + 1 is an upper limit for the
576 number of necessary entries. */
577 result = (struct r_search_path_elem **) malloc ((nelems + 1 + 1)
578 * sizeof (*result));
579 if (result == NULL)
581 errstring = N_("cannot create cache for search path");
582 signal_error:
583 _dl_signal_error (ENOMEM, NULL, NULL, errstring);
586 fillin_rpath (copy, result, ":", 0, what, where);
588 /* Free the copied RPATH string. `fillin_rpath' make own copies if
589 necessary. */
590 free (copy);
592 sps->dirs = result;
593 /* The caller will change this value if we haven't used a real malloc. */
594 sps->malloced = 1;
595 return true;
598 /* Make sure cached path information is stored in *SP
599 and return true if there are any paths to search there. */
600 static bool
601 cache_rpath (struct link_map *l,
602 struct r_search_path_struct *sp,
603 int tag,
604 const char *what)
606 if (sp->dirs == (void *) -1)
607 return false;
609 if (sp->dirs != NULL)
610 return true;
612 if (l->l_info[tag] == NULL)
614 /* There is no path. */
615 sp->dirs = (void *) -1;
616 return false;
619 /* Make sure the cache information is available. */
620 return decompose_rpath (sp, (const char *) (D_PTR (l, l_info[DT_STRTAB])
621 + l->l_info[tag]->d_un.d_val),
622 l, what);
626 void
627 internal_function
628 _dl_init_paths (const char *llp)
630 size_t idx;
631 const char *strp;
632 struct r_search_path_elem *pelem, **aelem;
633 size_t round_size;
634 #ifdef SHARED
635 struct link_map *l;
636 #endif
637 /* Initialize to please the compiler. */
638 const char *errstring = NULL;
640 /* Fill in the information about the application's RPATH and the
641 directories addressed by the LD_LIBRARY_PATH environment variable. */
643 /* Get the capabilities. */
644 capstr = _dl_important_hwcaps (GLRO(dl_platform), GLRO(dl_platformlen),
645 &ncapstr, &max_capstrlen);
647 /* First set up the rest of the default search directory entries. */
648 aelem = rtld_search_dirs.dirs = (struct r_search_path_elem **)
649 malloc ((nsystem_dirs_len + 1) * sizeof (struct r_search_path_elem *));
650 if (rtld_search_dirs.dirs == NULL)
652 errstring = N_("cannot create search path array");
653 signal_error:
654 _dl_signal_error (ENOMEM, NULL, NULL, errstring);
657 round_size = ((2 * sizeof (struct r_search_path_elem) - 1
658 + ncapstr * sizeof (enum r_dir_status))
659 / sizeof (struct r_search_path_elem));
661 rtld_search_dirs.dirs[0] = (struct r_search_path_elem *)
662 malloc ((sizeof (system_dirs) / sizeof (system_dirs[0]))
663 * round_size * sizeof (struct r_search_path_elem));
664 if (rtld_search_dirs.dirs[0] == NULL)
666 errstring = N_("cannot create cache for search path");
667 goto signal_error;
670 rtld_search_dirs.malloced = 0;
671 pelem = GL(dl_all_dirs) = rtld_search_dirs.dirs[0];
672 strp = system_dirs;
673 idx = 0;
677 size_t cnt;
679 *aelem++ = pelem;
681 pelem->what = "system search path";
682 pelem->where = NULL;
684 pelem->dirname = strp;
685 pelem->dirnamelen = system_dirs_len[idx];
686 strp += system_dirs_len[idx] + 1;
688 /* System paths must be absolute. */
689 assert (pelem->dirname[0] == '/');
690 for (cnt = 0; cnt < ncapstr; ++cnt)
691 pelem->status[cnt] = unknown;
693 pelem->next = (++idx == nsystem_dirs_len ? NULL : (pelem + round_size));
695 pelem += round_size;
697 while (idx < nsystem_dirs_len);
699 max_dirnamelen = SYSTEM_DIRS_MAX_LEN;
700 *aelem = NULL;
702 #ifdef SHARED
703 /* This points to the map of the main object. */
704 l = GL(dl_ns)[LM_ID_BASE]._ns_loaded;
705 if (l != NULL)
707 assert (l->l_type != lt_loaded);
709 if (l->l_info[DT_RUNPATH])
711 /* Allocate room for the search path and fill in information
712 from RUNPATH. */
713 decompose_rpath (&l->l_runpath_dirs,
714 (const void *) (D_PTR (l, l_info[DT_STRTAB])
715 + l->l_info[DT_RUNPATH]->d_un.d_val),
716 l, "RUNPATH");
718 /* The RPATH is ignored. */
719 l->l_rpath_dirs.dirs = (void *) -1;
721 else
723 l->l_runpath_dirs.dirs = (void *) -1;
725 if (l->l_info[DT_RPATH])
727 /* Allocate room for the search path and fill in information
728 from RPATH. */
729 decompose_rpath (&l->l_rpath_dirs,
730 (const void *) (D_PTR (l, l_info[DT_STRTAB])
731 + l->l_info[DT_RPATH]->d_un.d_val),
732 l, "RPATH");
733 l->l_rpath_dirs.malloced = 0;
735 else
736 l->l_rpath_dirs.dirs = (void *) -1;
739 #endif /* SHARED */
741 if (llp != NULL && *llp != '\0')
743 size_t nllp;
744 const char *cp = llp;
745 char *llp_tmp;
747 #ifdef SHARED
748 /* Expand DSTs. */
749 size_t cnt = DL_DST_COUNT (llp, 1);
750 if (__builtin_expect (cnt == 0, 1))
751 llp_tmp = strdupa (llp);
752 else
754 /* Determine the length of the substituted string. */
755 size_t total = DL_DST_REQUIRED (l, llp, strlen (llp), cnt);
757 /* Allocate the necessary memory. */
758 llp_tmp = (char *) alloca (total + 1);
759 llp_tmp = _dl_dst_substitute (l, llp, llp_tmp, 1);
761 #else
762 llp_tmp = strdupa (llp);
763 #endif
765 /* Decompose the LD_LIBRARY_PATH contents. First determine how many
766 elements it has. */
767 nllp = 1;
768 while (*cp)
770 if (*cp == ':' || *cp == ';')
771 ++nllp;
772 ++cp;
775 env_path_list.dirs = (struct r_search_path_elem **)
776 malloc ((nllp + 1) * sizeof (struct r_search_path_elem *));
777 if (env_path_list.dirs == NULL)
779 errstring = N_("cannot create cache for search path");
780 goto signal_error;
783 (void) fillin_rpath (llp_tmp, env_path_list.dirs, ":;",
784 INTUSE(__libc_enable_secure), "LD_LIBRARY_PATH",
785 NULL);
787 if (env_path_list.dirs[0] == NULL)
789 free (env_path_list.dirs);
790 env_path_list.dirs = (void *) -1;
793 env_path_list.malloced = 0;
795 else
796 env_path_list.dirs = (void *) -1;
798 /* Remember the last search directory added at startup. */
799 GLRO(dl_init_all_dirs) = GL(dl_all_dirs);
803 static void
804 __attribute__ ((noreturn, noinline))
805 lose (int code, int fd, const char *name, char *realname, struct link_map *l,
806 const char *msg, struct r_debug *r)
808 /* The file might already be closed. */
809 if (fd != -1)
810 (void) __close (fd);
811 if (l != NULL)
813 /* Remove the stillborn object from the list and free it. */
814 assert (l->l_next == NULL);
815 if (l->l_prev == NULL)
816 /* No other module loaded. This happens only in the static library,
817 or in rtld under --verify. */
818 GL(dl_ns)[l->l_ns]._ns_loaded = NULL;
819 else
820 l->l_prev->l_next = NULL;
821 --GL(dl_ns)[l->l_ns]._ns_nloaded;
822 free (l);
824 free (realname);
826 if (r != NULL)
828 r->r_state = RT_CONSISTENT;
829 _dl_debug_state ();
832 _dl_signal_error (code, name, NULL, msg);
836 /* Map in the shared object NAME, actually located in REALNAME, and already
837 opened on FD. */
839 #ifndef EXTERNAL_MAP_FROM_FD
840 static
841 #endif
842 struct link_map *
843 _dl_map_object_from_fd (const char *name, int fd, struct filebuf *fbp,
844 char *realname, struct link_map *loader, int l_type,
845 int mode, void **stack_endp, Lmid_t nsid)
847 struct link_map *l = NULL;
848 const ElfW(Ehdr) *header;
849 const ElfW(Phdr) *phdr;
850 const ElfW(Phdr) *ph;
851 size_t maplength;
852 int type;
853 struct stat64 st;
854 /* Initialize to keep the compiler happy. */
855 const char *errstring = NULL;
856 int errval = 0;
857 struct r_debug *r = _dl_debug_initialize (0, nsid);
858 bool make_consistent = false;
860 /* Get file information. */
861 if (__builtin_expect (__fxstat64 (_STAT_VER, fd, &st) < 0, 0))
863 errstring = N_("cannot stat shared object");
864 call_lose_errno:
865 errval = errno;
866 call_lose:
867 lose (errval, fd, name, realname, l, errstring,
868 make_consistent ? r : NULL);
871 /* Look again to see if the real name matched another already loaded. */
872 for (l = GL(dl_ns)[nsid]._ns_loaded; l; l = l->l_next)
873 if (l->l_removed == 0 && l->l_ino == st.st_ino && l->l_dev == st.st_dev)
875 /* The object is already loaded.
876 Just bump its reference count and return it. */
877 __close (fd);
879 /* If the name is not in the list of names for this object add
880 it. */
881 free (realname);
882 add_name_to_object (l, name);
884 return l;
887 #ifdef SHARED
888 /* When loading into a namespace other than the base one we must
889 avoid loading ld.so since there can only be one copy. Ever. */
890 if (__builtin_expect (nsid != LM_ID_BASE, 0)
891 && ((st.st_ino == GL(dl_rtld_map).l_ino
892 && st.st_dev == GL(dl_rtld_map).l_dev)
893 || _dl_name_match_p (name, &GL(dl_rtld_map))))
895 /* This is indeed ld.so. Create a new link_map which refers to
896 the real one for almost everything. */
897 l = _dl_new_object (realname, name, l_type, loader, mode, nsid);
898 if (l == NULL)
899 goto fail_new;
901 /* Refer to the real descriptor. */
902 l->l_real = &GL(dl_rtld_map);
904 /* No need to bump the refcount of the real object, ld.so will
905 never be unloaded. */
906 __close (fd);
908 return l;
910 #endif
912 if (mode & RTLD_NOLOAD)
913 /* We are not supposed to load the object unless it is already
914 loaded. So return now. */
915 return NULL;
917 /* Print debugging message. */
918 if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_FILES, 0))
919 _dl_debug_printf ("file=%s [%lu]; generating link map\n", name, nsid);
921 /* This is the ELF header. We read it in `open_verify'. */
922 header = (void *) fbp->buf;
924 #ifndef MAP_ANON
925 # define MAP_ANON 0
926 if (_dl_zerofd == -1)
928 _dl_zerofd = _dl_sysdep_open_zero_fill ();
929 if (_dl_zerofd == -1)
931 __close (fd);
932 _dl_signal_error (errno, NULL, NULL,
933 N_("cannot open zero fill device"));
936 #endif
938 /* Signal that we are going to add new objects. */
939 if (r->r_state == RT_CONSISTENT)
941 #ifdef SHARED
942 /* Auditing checkpoint: we are going to add new objects. */
943 if (__builtin_expect (GLRO(dl_naudit) > 0, 0))
945 struct link_map *head = GL(dl_ns)[nsid]._ns_loaded;
946 /* Do not call the functions for any auditing object. */
947 if (head->l_auditing == 0)
949 struct audit_ifaces *afct = GLRO(dl_audit);
950 for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt)
952 if (afct->activity != NULL)
953 afct->activity (&head->l_audit[cnt].cookie, LA_ACT_ADD);
955 afct = afct->next;
959 #endif
961 /* Notify the debugger we have added some objects. We need to
962 call _dl_debug_initialize in a static program in case dynamic
963 linking has not been used before. */
964 r->r_state = RT_ADD;
965 _dl_debug_state ();
966 make_consistent = true;
968 else
969 assert (r->r_state == RT_ADD);
971 /* Enter the new object in the list of loaded objects. */
972 l = _dl_new_object (realname, name, l_type, loader, mode, nsid);
973 if (__builtin_expect (l == NULL, 0))
975 #ifdef SHARED
976 fail_new:
977 #endif
978 errstring = N_("cannot create shared object descriptor");
979 goto call_lose_errno;
982 /* Extract the remaining details we need from the ELF header
983 and then read in the program header table. */
984 l->l_entry = header->e_entry;
985 type = header->e_type;
986 l->l_phnum = header->e_phnum;
988 maplength = header->e_phnum * sizeof (ElfW(Phdr));
989 if (header->e_phoff + maplength <= (size_t) fbp->len)
990 phdr = (void *) (fbp->buf + header->e_phoff);
991 else
993 phdr = alloca (maplength);
994 __lseek (fd, header->e_phoff, SEEK_SET);
995 if ((size_t) __libc_read (fd, (void *) phdr, maplength) != maplength)
997 errstring = N_("cannot read file data");
998 goto call_lose_errno;
1002 /* Presumed absent PT_GNU_STACK. */
1003 uint_fast16_t stack_flags = PF_R|PF_W|PF_X;
1006 /* Scan the program header table, collecting its load commands. */
1007 struct loadcmd
1009 ElfW(Addr) mapstart, mapend, dataend, allocend;
1010 off_t mapoff;
1011 int prot;
1012 } loadcmds[l->l_phnum], *c;
1013 size_t nloadcmds = 0;
1014 bool has_holes = false;
1016 /* The struct is initialized to zero so this is not necessary:
1017 l->l_ld = 0;
1018 l->l_phdr = 0;
1019 l->l_addr = 0; */
1020 for (ph = phdr; ph < &phdr[l->l_phnum]; ++ph)
1021 switch (ph->p_type)
1023 /* These entries tell us where to find things once the file's
1024 segments are mapped in. We record the addresses it says
1025 verbatim, and later correct for the run-time load address. */
1026 case PT_DYNAMIC:
1027 l->l_ld = (void *) ph->p_vaddr;
1028 l->l_ldnum = ph->p_memsz / sizeof (ElfW(Dyn));
1029 break;
1031 case PT_PHDR:
1032 l->l_phdr = (void *) ph->p_vaddr;
1033 break;
1035 case PT_LOAD:
1036 /* A load command tells us to map in part of the file.
1037 We record the load commands and process them all later. */
1038 if (__builtin_expect ((ph->p_align & (GLRO(dl_pagesize) - 1)) != 0,
1041 errstring = N_("ELF load command alignment not page-aligned");
1042 goto call_lose;
1044 if (__builtin_expect (((ph->p_vaddr - ph->p_offset)
1045 & (ph->p_align - 1)) != 0, 0))
1047 errstring
1048 = N_("ELF load command address/offset not properly aligned");
1049 goto call_lose;
1052 c = &loadcmds[nloadcmds++];
1053 c->mapstart = ph->p_vaddr & ~(GLRO(dl_pagesize) - 1);
1054 c->mapend = ((ph->p_vaddr + ph->p_filesz + GLRO(dl_pagesize) - 1)
1055 & ~(GLRO(dl_pagesize) - 1));
1056 c->dataend = ph->p_vaddr + ph->p_filesz;
1057 c->allocend = ph->p_vaddr + ph->p_memsz;
1058 c->mapoff = ph->p_offset & ~(GLRO(dl_pagesize) - 1);
1060 /* Determine whether there is a gap between the last segment
1061 and this one. */
1062 if (nloadcmds > 1 && c[-1].mapend != c->mapstart)
1063 has_holes = true;
1065 /* Optimize a common case. */
1066 #if (PF_R | PF_W | PF_X) == 7 && (PROT_READ | PROT_WRITE | PROT_EXEC) == 7
1067 c->prot = (PF_TO_PROT
1068 >> ((ph->p_flags & (PF_R | PF_W | PF_X)) * 4)) & 0xf;
1069 #else
1070 c->prot = 0;
1071 if (ph->p_flags & PF_R)
1072 c->prot |= PROT_READ;
1073 if (ph->p_flags & PF_W)
1074 c->prot |= PROT_WRITE;
1075 if (ph->p_flags & PF_X)
1076 c->prot |= PROT_EXEC;
1077 #endif
1078 break;
1080 case PT_TLS:
1081 if (ph->p_memsz == 0)
1082 /* Nothing to do for an empty segment. */
1083 break;
1085 l->l_tls_blocksize = ph->p_memsz;
1086 l->l_tls_align = ph->p_align;
1087 if (ph->p_align == 0)
1088 l->l_tls_firstbyte_offset = 0;
1089 else
1090 l->l_tls_firstbyte_offset = ph->p_vaddr & (ph->p_align - 1);
1091 l->l_tls_initimage_size = ph->p_filesz;
1092 /* Since we don't know the load address yet only store the
1093 offset. We will adjust it later. */
1094 l->l_tls_initimage = (void *) ph->p_vaddr;
1096 /* If not loading the initial set of shared libraries,
1097 check whether we should permit loading a TLS segment. */
1098 if (__builtin_expect (l->l_type == lt_library, 1)
1099 /* If GL(dl_tls_dtv_slotinfo_list) == NULL, then rtld.c did
1100 not set up TLS data structures, so don't use them now. */
1101 || __builtin_expect (GL(dl_tls_dtv_slotinfo_list) != NULL, 1))
1103 /* Assign the next available module ID. */
1104 l->l_tls_modid = _dl_next_tls_modid ();
1105 break;
1108 #ifdef SHARED
1109 if (l->l_prev == NULL || (mode & __RTLD_AUDIT) != 0)
1110 /* We are loading the executable itself when the dynamic linker
1111 was executed directly. The setup will happen later. */
1112 break;
1114 /* In a static binary there is no way to tell if we dynamically
1115 loaded libpthread. */
1116 if (GL(dl_error_catch_tsd) == &_dl_initial_error_catch_tsd)
1117 #endif
1119 /* We have not yet loaded libpthread.
1120 We can do the TLS setup right now! */
1122 void *tcb;
1124 /* The first call allocates TLS bookkeeping data structures.
1125 Then we allocate the TCB for the initial thread. */
1126 if (__builtin_expect (_dl_tls_setup (), 0)
1127 || __builtin_expect ((tcb = _dl_allocate_tls (NULL)) == NULL,
1130 errval = ENOMEM;
1131 errstring = N_("\
1132 cannot allocate TLS data structures for initial thread");
1133 goto call_lose;
1136 /* Now we install the TCB in the thread register. */
1137 errstring = TLS_INIT_TP (tcb, 0);
1138 if (__builtin_expect (errstring == NULL, 1))
1140 /* Now we are all good. */
1141 l->l_tls_modid = ++GL(dl_tls_max_dtv_idx);
1142 break;
1145 /* The kernel is too old or somesuch. */
1146 errval = 0;
1147 _dl_deallocate_tls (tcb, 1);
1148 goto call_lose;
1151 /* Uh-oh, the binary expects TLS support but we cannot
1152 provide it. */
1153 errval = 0;
1154 errstring = N_("cannot handle TLS data");
1155 goto call_lose;
1156 break;
1158 case PT_GNU_STACK:
1159 stack_flags = ph->p_flags;
1160 break;
1162 case PT_GNU_RELRO:
1163 l->l_relro_addr = ph->p_vaddr;
1164 l->l_relro_size = ph->p_memsz;
1165 break;
1168 if (__builtin_expect (nloadcmds == 0, 0))
1170 /* This only happens for a bogus object that will be caught with
1171 another error below. But we don't want to go through the
1172 calculations below using NLOADCMDS - 1. */
1173 errstring = N_("object file has no loadable segments");
1174 goto call_lose;
1177 /* Now process the load commands and map segments into memory. */
1178 c = loadcmds;
1180 /* Length of the sections to be loaded. */
1181 maplength = loadcmds[nloadcmds - 1].allocend - c->mapstart;
1183 if (__builtin_expect (type, ET_DYN) == ET_DYN)
1185 /* This is a position-independent shared object. We can let the
1186 kernel map it anywhere it likes, but we must have space for all
1187 the segments in their specified positions relative to the first.
1188 So we map the first segment without MAP_FIXED, but with its
1189 extent increased to cover all the segments. Then we remove
1190 access from excess portion, and there is known sufficient space
1191 there to remap from the later segments.
1193 As a refinement, sometimes we have an address that we would
1194 prefer to map such objects at; but this is only a preference,
1195 the OS can do whatever it likes. */
1196 ElfW(Addr) mappref;
1197 mappref = (ELF_PREFERRED_ADDRESS (loader, maplength,
1198 c->mapstart & GLRO(dl_use_load_bias))
1199 - MAP_BASE_ADDR (l));
1201 /* Remember which part of the address space this object uses. */
1202 l->l_map_start = (ElfW(Addr)) __mmap ((void *) mappref, maplength,
1203 c->prot,
1204 MAP_COPY|MAP_FILE,
1205 fd, c->mapoff);
1206 if (__builtin_expect ((void *) l->l_map_start == MAP_FAILED, 0))
1208 map_error:
1209 errstring = N_("failed to map segment from shared object");
1210 goto call_lose_errno;
1213 l->l_map_end = l->l_map_start + maplength;
1214 l->l_addr = l->l_map_start - c->mapstart;
1216 if (has_holes)
1217 /* Change protection on the excess portion to disallow all access;
1218 the portions we do not remap later will be inaccessible as if
1219 unallocated. Then jump into the normal segment-mapping loop to
1220 handle the portion of the segment past the end of the file
1221 mapping. */
1222 __mprotect ((caddr_t) (l->l_addr + c->mapend),
1223 loadcmds[nloadcmds - 1].mapstart - c->mapend,
1224 PROT_NONE);
1226 l->l_contiguous = 1;
1228 goto postmap;
1231 /* This object is loaded at a fixed address. This must never
1232 happen for objects loaded with dlopen(). */
1233 if (__builtin_expect ((mode & __RTLD_OPENEXEC) == 0, 0))
1235 errstring = N_("cannot dynamically load executable");
1236 goto call_lose;
1239 /* Notify ELF_PREFERRED_ADDRESS that we have to load this one
1240 fixed. */
1241 ELF_FIXED_ADDRESS (loader, c->mapstart);
1244 /* Remember which part of the address space this object uses. */
1245 l->l_map_start = c->mapstart + l->l_addr;
1246 l->l_map_end = l->l_map_start + maplength;
1247 l->l_contiguous = !has_holes;
1249 while (c < &loadcmds[nloadcmds])
1251 if (c->mapend > c->mapstart
1252 /* Map the segment contents from the file. */
1253 && (__mmap ((void *) (l->l_addr + c->mapstart),
1254 c->mapend - c->mapstart, c->prot,
1255 MAP_FIXED|MAP_COPY|MAP_FILE,
1256 fd, c->mapoff)
1257 == MAP_FAILED))
1258 goto map_error;
1260 postmap:
1261 if (c->prot & PROT_EXEC)
1262 l->l_text_end = l->l_addr + c->mapend;
1264 if (l->l_phdr == 0
1265 && (ElfW(Off)) c->mapoff <= header->e_phoff
1266 && ((size_t) (c->mapend - c->mapstart + c->mapoff)
1267 >= header->e_phoff + header->e_phnum * sizeof (ElfW(Phdr))))
1268 /* Found the program header in this segment. */
1269 l->l_phdr = (void *) (c->mapstart + header->e_phoff - c->mapoff);
1271 if (c->allocend > c->dataend)
1273 /* Extra zero pages should appear at the end of this segment,
1274 after the data mapped from the file. */
1275 ElfW(Addr) zero, zeroend, zeropage;
1277 zero = l->l_addr + c->dataend;
1278 zeroend = l->l_addr + c->allocend;
1279 zeropage = ((zero + GLRO(dl_pagesize) - 1)
1280 & ~(GLRO(dl_pagesize) - 1));
1282 if (zeroend < zeropage)
1283 /* All the extra data is in the last page of the segment.
1284 We can just zero it. */
1285 zeropage = zeroend;
1287 if (zeropage > zero)
1289 /* Zero the final part of the last page of the segment. */
1290 if (__builtin_expect ((c->prot & PROT_WRITE) == 0, 0))
1292 /* Dag nab it. */
1293 if (__mprotect ((caddr_t) (zero
1294 & ~(GLRO(dl_pagesize) - 1)),
1295 GLRO(dl_pagesize), c->prot|PROT_WRITE) < 0)
1297 errstring = N_("cannot change memory protections");
1298 goto call_lose_errno;
1301 memset ((void *) zero, '\0', zeropage - zero);
1302 if (__builtin_expect ((c->prot & PROT_WRITE) == 0, 0))
1303 __mprotect ((caddr_t) (zero & ~(GLRO(dl_pagesize) - 1)),
1304 GLRO(dl_pagesize), c->prot);
1307 if (zeroend > zeropage)
1309 /* Map the remaining zero pages in from the zero fill FD. */
1310 caddr_t mapat;
1311 mapat = __mmap ((caddr_t) zeropage, zeroend - zeropage,
1312 c->prot, MAP_ANON|MAP_PRIVATE|MAP_FIXED,
1313 ANONFD, 0);
1314 if (__builtin_expect (mapat == MAP_FAILED, 0))
1316 errstring = N_("cannot map zero-fill pages");
1317 goto call_lose_errno;
1322 ++c;
1326 if (l->l_ld == 0)
1328 if (__builtin_expect (type == ET_DYN, 0))
1330 errstring = N_("object file has no dynamic section");
1331 goto call_lose;
1334 else
1335 l->l_ld = (ElfW(Dyn) *) ((ElfW(Addr)) l->l_ld + l->l_addr);
1337 elf_get_dynamic_info (l, NULL);
1339 /* Make sure we are not dlopen'ing an object that has the
1340 DF_1_NOOPEN flag set. */
1341 if (__builtin_expect (l->l_flags_1 & DF_1_NOOPEN, 0)
1342 && (mode & __RTLD_DLOPEN))
1344 /* We are not supposed to load this object. Free all resources. */
1345 __munmap ((void *) l->l_map_start, l->l_map_end - l->l_map_start);
1347 if (!l->l_libname->dont_free)
1348 free (l->l_libname);
1350 if (l->l_phdr_allocated)
1351 free ((void *) l->l_phdr);
1353 errstring = N_("shared object cannot be dlopen()ed");
1354 goto call_lose;
1357 if (l->l_phdr == NULL)
1359 /* The program header is not contained in any of the segments.
1360 We have to allocate memory ourself and copy it over from out
1361 temporary place. */
1362 ElfW(Phdr) *newp = (ElfW(Phdr) *) malloc (header->e_phnum
1363 * sizeof (ElfW(Phdr)));
1364 if (newp == NULL)
1366 errstring = N_("cannot allocate memory for program header");
1367 goto call_lose_errno;
1370 l->l_phdr = memcpy (newp, phdr,
1371 (header->e_phnum * sizeof (ElfW(Phdr))));
1372 l->l_phdr_allocated = 1;
1374 else
1375 /* Adjust the PT_PHDR value by the runtime load address. */
1376 l->l_phdr = (ElfW(Phdr) *) ((ElfW(Addr)) l->l_phdr + l->l_addr);
1378 if (__builtin_expect ((stack_flags &~ GL(dl_stack_flags)) & PF_X, 0))
1380 if (__builtin_expect (__check_caller (RETURN_ADDRESS (0), allow_ldso),
1381 0) != 0)
1383 errstring = N_("invalid caller");
1384 goto call_lose;
1387 /* The stack is presently not executable, but this module
1388 requires that it be executable. We must change the
1389 protection of the variable which contains the flags used in
1390 the mprotect calls. */
1391 #ifdef SHARED
1392 if ((mode & (__RTLD_DLOPEN | __RTLD_AUDIT)) == __RTLD_DLOPEN)
1394 const uintptr_t p = (uintptr_t) &__stack_prot & -GLRO(dl_pagesize);
1395 const size_t s = (uintptr_t) (&__stack_prot + 1) - p;
1397 struct link_map *const m = &GL(dl_rtld_map);
1398 const uintptr_t relro_end = ((m->l_addr + m->l_relro_addr
1399 + m->l_relro_size)
1400 & -GLRO(dl_pagesize));
1401 if (__builtin_expect (p + s <= relro_end, 1))
1403 /* The variable lies in the region protected by RELRO. */
1404 __mprotect ((void *) p, s, PROT_READ|PROT_WRITE);
1405 __stack_prot |= PROT_READ|PROT_WRITE|PROT_EXEC;
1406 __mprotect ((void *) p, s, PROT_READ);
1408 else
1409 __stack_prot |= PROT_READ|PROT_WRITE|PROT_EXEC;
1411 else
1412 #endif
1413 __stack_prot |= PROT_READ|PROT_WRITE|PROT_EXEC;
1415 #ifdef check_consistency
1416 check_consistency ();
1417 #endif
1419 errval = (*GL(dl_make_stack_executable_hook)) (stack_endp);
1420 if (errval)
1422 errstring = N_("\
1423 cannot enable executable stack as shared object requires");
1424 goto call_lose;
1428 /* Adjust the address of the TLS initialization image. */
1429 if (l->l_tls_initimage != NULL)
1430 l->l_tls_initimage = (char *) l->l_tls_initimage + l->l_addr;
1432 /* We are done mapping in the file. We no longer need the descriptor. */
1433 if (__builtin_expect (__close (fd) != 0, 0))
1435 errstring = N_("cannot close file descriptor");
1436 goto call_lose_errno;
1438 /* Signal that we closed the file. */
1439 fd = -1;
1441 if (l->l_type == lt_library && type == ET_EXEC)
1442 l->l_type = lt_executable;
1444 l->l_entry += l->l_addr;
1446 if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_FILES, 0))
1447 _dl_debug_printf ("\
1448 dynamic: 0x%0*lx base: 0x%0*lx size: 0x%0*Zx\n\
1449 entry: 0x%0*lx phdr: 0x%0*lx phnum: %*u\n\n",
1450 (int) sizeof (void *) * 2,
1451 (unsigned long int) l->l_ld,
1452 (int) sizeof (void *) * 2,
1453 (unsigned long int) l->l_addr,
1454 (int) sizeof (void *) * 2, maplength,
1455 (int) sizeof (void *) * 2,
1456 (unsigned long int) l->l_entry,
1457 (int) sizeof (void *) * 2,
1458 (unsigned long int) l->l_phdr,
1459 (int) sizeof (void *) * 2, l->l_phnum);
1461 /* Set up the symbol hash table. */
1462 _dl_setup_hash (l);
1464 /* If this object has DT_SYMBOLIC set modify now its scope. We don't
1465 have to do this for the main map. */
1466 if ((mode & RTLD_DEEPBIND) == 0
1467 && __builtin_expect (l->l_info[DT_SYMBOLIC] != NULL, 0)
1468 && &l->l_searchlist != l->l_scope[0])
1470 /* Create an appropriate searchlist. It contains only this map.
1471 This is the definition of DT_SYMBOLIC in SysVr4. */
1472 l->l_symbolic_searchlist.r_list =
1473 (struct link_map **) malloc (sizeof (struct link_map *));
1475 if (l->l_symbolic_searchlist.r_list == NULL)
1477 errstring = N_("cannot create searchlist");
1478 goto call_lose_errno;
1481 l->l_symbolic_searchlist.r_list[0] = l;
1482 l->l_symbolic_searchlist.r_nlist = 1;
1484 /* Now move the existing entries one back. */
1485 memmove (&l->l_scope[1], &l->l_scope[0],
1486 (l->l_scope_max - 1) * sizeof (l->l_scope[0]));
1488 /* Now add the new entry. */
1489 l->l_scope[0] = &l->l_symbolic_searchlist;
1492 /* Remember whether this object must be initialized first. */
1493 if (l->l_flags_1 & DF_1_INITFIRST)
1494 GL(dl_initfirst) = l;
1496 /* Finally the file information. */
1497 l->l_dev = st.st_dev;
1498 l->l_ino = st.st_ino;
1500 /* When we profile the SONAME might be needed for something else but
1501 loading. Add it right away. */
1502 if (__builtin_expect (GLRO(dl_profile) != NULL, 0)
1503 && l->l_info[DT_SONAME] != NULL)
1504 add_name_to_object (l, ((const char *) D_PTR (l, l_info[DT_STRTAB])
1505 + l->l_info[DT_SONAME]->d_un.d_val));
1507 #ifdef SHARED
1508 /* Auditing checkpoint: we have a new object. */
1509 if (__builtin_expect (GLRO(dl_naudit) > 0, 0)
1510 && !GL(dl_ns)[l->l_ns]._ns_loaded->l_auditing)
1512 struct audit_ifaces *afct = GLRO(dl_audit);
1513 for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt)
1515 if (afct->objopen != NULL)
1517 l->l_audit[cnt].bindflags
1518 = afct->objopen (l, nsid, &l->l_audit[cnt].cookie);
1520 l->l_audit_any_plt |= l->l_audit[cnt].bindflags != 0;
1523 afct = afct->next;
1526 #endif
1528 return l;
1531 /* Print search path. */
1532 static void
1533 print_search_path (struct r_search_path_elem **list,
1534 const char *what, const char *name)
1536 char buf[max_dirnamelen + max_capstrlen];
1537 int first = 1;
1539 _dl_debug_printf (" search path=");
1541 while (*list != NULL && (*list)->what == what) /* Yes, ==. */
1543 char *endp = __mempcpy (buf, (*list)->dirname, (*list)->dirnamelen);
1544 size_t cnt;
1546 for (cnt = 0; cnt < ncapstr; ++cnt)
1547 if ((*list)->status[cnt] != nonexisting)
1549 char *cp = __mempcpy (endp, capstr[cnt].str, capstr[cnt].len);
1550 if (cp == buf || (cp == buf + 1 && buf[0] == '/'))
1551 cp[0] = '\0';
1552 else
1553 cp[-1] = '\0';
1555 _dl_debug_printf_c (first ? "%s" : ":%s", buf);
1556 first = 0;
1559 ++list;
1562 if (name != NULL)
1563 _dl_debug_printf_c ("\t\t(%s from file %s)\n", what,
1564 name[0] ? name : rtld_progname);
1565 else
1566 _dl_debug_printf_c ("\t\t(%s)\n", what);
1569 /* Open a file and verify it is an ELF file for this architecture. We
1570 ignore only ELF files for other architectures. Non-ELF files and
1571 ELF files with different header information cause fatal errors since
1572 this could mean there is something wrong in the installation and the
1573 user might want to know about this. */
1574 static int
1575 open_verify (const char *name, struct filebuf *fbp, struct link_map *loader,
1576 int whatcode, bool *found_other_class, bool free_name)
1578 /* This is the expected ELF header. */
1579 #define ELF32_CLASS ELFCLASS32
1580 #define ELF64_CLASS ELFCLASS64
1581 #ifndef VALID_ELF_HEADER
1582 # define VALID_ELF_HEADER(hdr,exp,size) (memcmp (hdr, exp, size) == 0)
1583 # define VALID_ELF_OSABI(osabi) (osabi == ELFOSABI_SYSV)
1584 # define VALID_ELF_ABIVERSION(ver) (ver == 0)
1585 #endif
1586 static const unsigned char expected[EI_PAD] =
1588 [EI_MAG0] = ELFMAG0,
1589 [EI_MAG1] = ELFMAG1,
1590 [EI_MAG2] = ELFMAG2,
1591 [EI_MAG3] = ELFMAG3,
1592 [EI_CLASS] = ELFW(CLASS),
1593 [EI_DATA] = byteorder,
1594 [EI_VERSION] = EV_CURRENT,
1595 [EI_OSABI] = ELFOSABI_SYSV,
1596 [EI_ABIVERSION] = 0
1598 static const struct
1600 ElfW(Word) vendorlen;
1601 ElfW(Word) datalen;
1602 ElfW(Word) type;
1603 char vendor[4];
1604 } expected_note = { 4, 16, 1, "GNU" };
1605 /* Initialize it to make the compiler happy. */
1606 const char *errstring = NULL;
1607 int errval = 0;
1609 #ifdef SHARED
1610 /* Give the auditing libraries a chance. */
1611 if (__builtin_expect (GLRO(dl_naudit) > 0, 0) && whatcode != 0
1612 && loader->l_auditing == 0)
1614 struct audit_ifaces *afct = GLRO(dl_audit);
1615 for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt)
1617 if (afct->objsearch != NULL)
1619 name = afct->objsearch (name, &loader->l_audit[cnt].cookie,
1620 whatcode);
1621 if (name == NULL)
1622 /* Ignore the path. */
1623 return -1;
1626 afct = afct->next;
1629 #endif
1631 /* Open the file. We always open files read-only. */
1632 int fd = __open (name, O_RDONLY);
1633 if (fd != -1)
1635 ElfW(Ehdr) *ehdr;
1636 ElfW(Phdr) *phdr, *ph;
1637 ElfW(Word) *abi_note;
1638 unsigned int osversion;
1639 size_t maplength;
1641 /* We successfully openened the file. Now verify it is a file
1642 we can use. */
1643 __set_errno (0);
1644 fbp->len = __libc_read (fd, fbp->buf, sizeof (fbp->buf));
1646 /* This is where the ELF header is loaded. */
1647 assert (sizeof (fbp->buf) > sizeof (ElfW(Ehdr)));
1648 ehdr = (ElfW(Ehdr) *) fbp->buf;
1650 /* Now run the tests. */
1651 if (__builtin_expect (fbp->len < (ssize_t) sizeof (ElfW(Ehdr)), 0))
1653 errval = errno;
1654 errstring = (errval == 0
1655 ? N_("file too short") : N_("cannot read file data"));
1656 call_lose:
1657 if (free_name)
1659 char *realname = (char *) name;
1660 name = strdupa (realname);
1661 free (realname);
1663 lose (errval, fd, name, NULL, NULL, errstring, NULL);
1666 /* See whether the ELF header is what we expect. */
1667 if (__builtin_expect (! VALID_ELF_HEADER (ehdr->e_ident, expected,
1668 EI_PAD), 0))
1670 /* Something is wrong. */
1671 if (*(Elf32_Word *) &ehdr->e_ident !=
1672 #if BYTE_ORDER == LITTLE_ENDIAN
1673 ((ELFMAG0 << (EI_MAG0 * 8)) |
1674 (ELFMAG1 << (EI_MAG1 * 8)) |
1675 (ELFMAG2 << (EI_MAG2 * 8)) |
1676 (ELFMAG3 << (EI_MAG3 * 8)))
1677 #else
1678 ((ELFMAG0 << (EI_MAG3 * 8)) |
1679 (ELFMAG1 << (EI_MAG2 * 8)) |
1680 (ELFMAG2 << (EI_MAG1 * 8)) |
1681 (ELFMAG3 << (EI_MAG0 * 8)))
1682 #endif
1684 errstring = N_("invalid ELF header");
1685 else if (ehdr->e_ident[EI_CLASS] != ELFW(CLASS))
1687 /* This is not a fatal error. On architectures where
1688 32-bit and 64-bit binaries can be run this might
1689 happen. */
1690 *found_other_class = true;
1691 goto close_and_out;
1693 else if (ehdr->e_ident[EI_DATA] != byteorder)
1695 if (BYTE_ORDER == BIG_ENDIAN)
1696 errstring = N_("ELF file data encoding not big-endian");
1697 else
1698 errstring = N_("ELF file data encoding not little-endian");
1700 else if (ehdr->e_ident[EI_VERSION] != EV_CURRENT)
1701 errstring
1702 = N_("ELF file version ident does not match current one");
1703 /* XXX We should be able so set system specific versions which are
1704 allowed here. */
1705 else if (!VALID_ELF_OSABI (ehdr->e_ident[EI_OSABI]))
1706 errstring = N_("ELF file OS ABI invalid");
1707 else if (!VALID_ELF_ABIVERSION (ehdr->e_ident[EI_ABIVERSION]))
1708 errstring = N_("ELF file ABI version invalid");
1709 else
1710 /* Otherwise we don't know what went wrong. */
1711 errstring = N_("internal error");
1713 goto call_lose;
1716 if (__builtin_expect (ehdr->e_version, EV_CURRENT) != EV_CURRENT)
1718 errstring = N_("ELF file version does not match current one");
1719 goto call_lose;
1721 if (! __builtin_expect (elf_machine_matches_host (ehdr), 1))
1722 goto close_and_out;
1723 else if (__builtin_expect (ehdr->e_type, ET_DYN) != ET_DYN
1724 && __builtin_expect (ehdr->e_type, ET_EXEC) != ET_EXEC)
1726 errstring = N_("only ET_DYN and ET_EXEC can be loaded");
1727 goto call_lose;
1729 else if (__builtin_expect (ehdr->e_phentsize, sizeof (ElfW(Phdr)))
1730 != sizeof (ElfW(Phdr)))
1732 errstring = N_("ELF file's phentsize not the expected size");
1733 goto call_lose;
1736 maplength = ehdr->e_phnum * sizeof (ElfW(Phdr));
1737 if (ehdr->e_phoff + maplength <= (size_t) fbp->len)
1738 phdr = (void *) (fbp->buf + ehdr->e_phoff);
1739 else
1741 phdr = alloca (maplength);
1742 __lseek (fd, ehdr->e_phoff, SEEK_SET);
1743 if ((size_t) __libc_read (fd, (void *) phdr, maplength) != maplength)
1745 read_error:
1746 errval = errno;
1747 errstring = N_("cannot read file data");
1748 goto call_lose;
1752 /* Check .note.ABI-tag if present. */
1753 for (ph = phdr; ph < &phdr[ehdr->e_phnum]; ++ph)
1754 if (ph->p_type == PT_NOTE && ph->p_filesz >= 32 && ph->p_align >= 4)
1756 ElfW(Addr) size = ph->p_filesz;
1758 if (ph->p_offset + size <= (size_t) fbp->len)
1759 abi_note = (void *) (fbp->buf + ph->p_offset);
1760 else
1762 abi_note = alloca (size);
1763 __lseek (fd, ph->p_offset, SEEK_SET);
1764 if (__libc_read (fd, (void *) abi_note, size) != size)
1765 goto read_error;
1768 while (memcmp (abi_note, &expected_note, sizeof (expected_note)))
1770 #define ROUND(len) (((len) + sizeof (ElfW(Word)) - 1) & -sizeof (ElfW(Word)))
1771 ElfW(Addr) note_size = 3 * sizeof (ElfW(Word))
1772 + ROUND (abi_note[0])
1773 + ROUND (abi_note[1]);
1775 if (size - 32 < note_size)
1777 size = 0;
1778 break;
1780 size -= note_size;
1781 abi_note = (void *) abi_note + note_size;
1784 if (size == 0)
1785 continue;
1787 osversion = (abi_note[5] & 0xff) * 65536
1788 + (abi_note[6] & 0xff) * 256
1789 + (abi_note[7] & 0xff);
1790 if (abi_note[4] != __ABI_TAG_OS
1791 || (GLRO(dl_osversion) && GLRO(dl_osversion) < osversion))
1793 close_and_out:
1794 __close (fd);
1795 __set_errno (ENOENT);
1796 fd = -1;
1799 break;
1803 return fd;
1806 /* Try to open NAME in one of the directories in *DIRSP.
1807 Return the fd, or -1. If successful, fill in *REALNAME
1808 with the malloc'd full directory name. If it turns out
1809 that none of the directories in *DIRSP exists, *DIRSP is
1810 replaced with (void *) -1, and the old value is free()d
1811 if MAY_FREE_DIRS is true. */
1813 static int
1814 open_path (const char *name, size_t namelen, int preloaded,
1815 struct r_search_path_struct *sps, char **realname,
1816 struct filebuf *fbp, struct link_map *loader, int whatcode,
1817 bool *found_other_class)
1819 struct r_search_path_elem **dirs = sps->dirs;
1820 char *buf;
1821 int fd = -1;
1822 const char *current_what = NULL;
1823 int any = 0;
1825 if (__builtin_expect (dirs == NULL, 0))
1826 /* We're called before _dl_init_paths when loading the main executable
1827 given on the command line when rtld is run directly. */
1828 return -1;
1830 buf = alloca (max_dirnamelen + max_capstrlen + namelen);
1833 struct r_search_path_elem *this_dir = *dirs;
1834 size_t buflen = 0;
1835 size_t cnt;
1836 char *edp;
1837 int here_any = 0;
1838 int err;
1840 /* If we are debugging the search for libraries print the path
1841 now if it hasn't happened now. */
1842 if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_LIBS, 0)
1843 && current_what != this_dir->what)
1845 current_what = this_dir->what;
1846 print_search_path (dirs, current_what, this_dir->where);
1849 edp = (char *) __mempcpy (buf, this_dir->dirname, this_dir->dirnamelen);
1850 for (cnt = 0; fd == -1 && cnt < ncapstr; ++cnt)
1852 /* Skip this directory if we know it does not exist. */
1853 if (this_dir->status[cnt] == nonexisting)
1854 continue;
1856 buflen =
1857 ((char *) __mempcpy (__mempcpy (edp, capstr[cnt].str,
1858 capstr[cnt].len),
1859 name, namelen)
1860 - buf);
1862 /* Print name we try if this is wanted. */
1863 if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_LIBS, 0))
1864 _dl_debug_printf (" trying file=%s\n", buf);
1866 fd = open_verify (buf, fbp, loader, whatcode, found_other_class,
1867 false);
1868 if (this_dir->status[cnt] == unknown)
1870 if (fd != -1)
1871 this_dir->status[cnt] = existing;
1872 /* Do not update the directory information when loading
1873 auditing code. We must try to disturb the program as
1874 little as possible. */
1875 else if (loader == NULL
1876 || GL(dl_ns)[loader->l_ns]._ns_loaded->l_auditing == 0)
1878 /* We failed to open machine dependent library. Let's
1879 test whether there is any directory at all. */
1880 struct stat64 st;
1882 buf[buflen - namelen - 1] = '\0';
1884 if (__xstat64 (_STAT_VER, buf, &st) != 0
1885 || ! S_ISDIR (st.st_mode))
1886 /* The directory does not exist or it is no directory. */
1887 this_dir->status[cnt] = nonexisting;
1888 else
1889 this_dir->status[cnt] = existing;
1893 /* Remember whether we found any existing directory. */
1894 here_any |= this_dir->status[cnt] != nonexisting;
1896 if (fd != -1 && __builtin_expect (preloaded, 0)
1897 && INTUSE(__libc_enable_secure))
1899 /* This is an extra security effort to make sure nobody can
1900 preload broken shared objects which are in the trusted
1901 directories and so exploit the bugs. */
1902 struct stat64 st;
1904 if (__fxstat64 (_STAT_VER, fd, &st) != 0
1905 || (st.st_mode & S_ISUID) == 0)
1907 /* The shared object cannot be tested for being SUID
1908 or this bit is not set. In this case we must not
1909 use this object. */
1910 __close (fd);
1911 fd = -1;
1912 /* We simply ignore the file, signal this by setting
1913 the error value which would have been set by `open'. */
1914 errno = ENOENT;
1919 if (fd != -1)
1921 *realname = (char *) malloc (buflen);
1922 if (*realname != NULL)
1924 memcpy (*realname, buf, buflen);
1925 return fd;
1927 else
1929 /* No memory for the name, we certainly won't be able
1930 to load and link it. */
1931 __close (fd);
1932 return -1;
1935 if (here_any && (err = errno) != ENOENT && err != EACCES)
1936 /* The file exists and is readable, but something went wrong. */
1937 return -1;
1939 /* Remember whether we found anything. */
1940 any |= here_any;
1942 while (*++dirs != NULL);
1944 /* Remove the whole path if none of the directories exists. */
1945 if (__builtin_expect (! any, 0))
1947 /* Paths which were allocated using the minimal malloc() in ld.so
1948 must not be freed using the general free() in libc. */
1949 if (sps->malloced)
1950 free (sps->dirs);
1952 /* rtld_search_dirs is attribute_relro, therefore avoid writing
1953 into it. */
1954 if (sps != &rtld_search_dirs)
1955 sps->dirs = (void *) -1;
1958 return -1;
1961 /* Map in the shared object file NAME. */
1963 struct link_map *
1964 internal_function
1965 _dl_map_object (struct link_map *loader, const char *name, int preloaded,
1966 int type, int trace_mode, int mode, Lmid_t nsid)
1968 int fd;
1969 char *realname;
1970 char *name_copy;
1971 struct link_map *l;
1972 struct filebuf fb;
1974 assert (nsid >= 0);
1975 assert (nsid < DL_NNS);
1977 /* Look for this name among those already loaded. */
1978 for (l = GL(dl_ns)[nsid]._ns_loaded; l; l = l->l_next)
1980 /* If the requested name matches the soname of a loaded object,
1981 use that object. Elide this check for names that have not
1982 yet been opened. */
1983 if (__builtin_expect (l->l_faked, 0) != 0
1984 || __builtin_expect (l->l_removed, 0) != 0)
1985 continue;
1986 if (!_dl_name_match_p (name, l))
1988 const char *soname;
1990 if (__builtin_expect (l->l_soname_added, 1)
1991 || l->l_info[DT_SONAME] == NULL)
1992 continue;
1994 soname = ((const char *) D_PTR (l, l_info[DT_STRTAB])
1995 + l->l_info[DT_SONAME]->d_un.d_val);
1996 if (strcmp (name, soname) != 0)
1997 continue;
1999 /* We have a match on a new name -- cache it. */
2000 add_name_to_object (l, soname);
2001 l->l_soname_added = 1;
2004 /* We have a match. */
2005 return l;
2008 /* Display information if we are debugging. */
2009 if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_FILES, 0)
2010 && loader != NULL)
2011 _dl_debug_printf ("\nfile=%s [%lu]; needed by %s [%lu]\n", name, nsid,
2012 loader->l_name[0]
2013 ? loader->l_name : rtld_progname, loader->l_ns);
2015 #ifdef SHARED
2016 /* Give the auditing libraries a chance to change the name before we
2017 try anything. */
2018 if (__builtin_expect (GLRO(dl_naudit) > 0, 0)
2019 && (loader == NULL || loader->l_auditing == 0))
2021 struct audit_ifaces *afct = GLRO(dl_audit);
2022 for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt)
2024 if (afct->objsearch != NULL)
2026 name = afct->objsearch (name, &loader->l_audit[cnt].cookie,
2027 LA_SER_ORIG);
2028 if (name == NULL)
2030 /* Do not try anything further. */
2031 fd = -1;
2032 goto no_file;
2036 afct = afct->next;
2039 #endif
2041 /* Will be true if we found a DSO which is of the other ELF class. */
2042 bool found_other_class = false;
2044 if (strchr (name, '/') == NULL)
2046 /* Search for NAME in several places. */
2048 size_t namelen = strlen (name) + 1;
2050 if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_LIBS, 0))
2051 _dl_debug_printf ("find library=%s [%lu]; searching\n", name, nsid);
2053 fd = -1;
2055 /* When the object has the RUNPATH information we don't use any
2056 RPATHs. */
2057 if (loader == NULL || loader->l_info[DT_RUNPATH] == NULL)
2059 /* This is the executable's map (if there is one). Make sure that
2060 we do not look at it twice. */
2061 struct link_map *main_map = GL(dl_ns)[LM_ID_BASE]._ns_loaded;
2062 bool did_main_map = false;
2064 /* First try the DT_RPATH of the dependent object that caused NAME
2065 to be loaded. Then that object's dependent, and on up. */
2066 for (l = loader; l; l = l->l_loader)
2067 if (cache_rpath (l, &l->l_rpath_dirs, DT_RPATH, "RPATH"))
2069 fd = open_path (name, namelen, preloaded, &l->l_rpath_dirs,
2070 &realname, &fb, loader, LA_SER_RUNPATH,
2071 &found_other_class);
2072 if (fd != -1)
2073 break;
2075 did_main_map |= l == main_map;
2078 /* If dynamically linked, try the DT_RPATH of the executable
2079 itself. NB: we do this for lookups in any namespace. */
2080 if (fd == -1 && !did_main_map
2081 && main_map != NULL && main_map->l_type != lt_loaded
2082 && cache_rpath (main_map, &main_map->l_rpath_dirs, DT_RPATH,
2083 "RPATH"))
2084 fd = open_path (name, namelen, preloaded, &main_map->l_rpath_dirs,
2085 &realname, &fb, loader ?: main_map, LA_SER_RUNPATH,
2086 &found_other_class);
2089 /* Try the LD_LIBRARY_PATH environment variable. */
2090 if (fd == -1 && env_path_list.dirs != (void *) -1)
2091 fd = open_path (name, namelen, preloaded, &env_path_list,
2092 &realname, &fb,
2093 loader ?: GL(dl_ns)[LM_ID_BASE]._ns_loaded,
2094 LA_SER_LIBPATH, &found_other_class);
2096 /* Look at the RUNPATH information for this binary. */
2097 if (fd == -1 && loader != NULL
2098 && cache_rpath (loader, &loader->l_runpath_dirs,
2099 DT_RUNPATH, "RUNPATH"))
2100 fd = open_path (name, namelen, preloaded,
2101 &loader->l_runpath_dirs, &realname, &fb, loader,
2102 LA_SER_RUNPATH, &found_other_class);
2104 if (fd == -1
2105 && (__builtin_expect (! preloaded, 1)
2106 || ! INTUSE(__libc_enable_secure)))
2108 /* Check the list of libraries in the file /etc/ld.so.cache,
2109 for compatibility with Linux's ldconfig program. */
2110 const char *cached = _dl_load_cache_lookup (name);
2112 if (cached != NULL)
2114 #ifdef SHARED
2115 // XXX Correct to unconditionally default to namespace 0?
2116 l = loader ?: GL(dl_ns)[LM_ID_BASE]._ns_loaded;
2117 #else
2118 l = loader;
2119 #endif
2121 /* If the loader has the DF_1_NODEFLIB flag set we must not
2122 use a cache entry from any of these directories. */
2123 if (
2124 #ifndef SHARED
2125 /* 'l' is always != NULL for dynamically linked objects. */
2126 l != NULL &&
2127 #endif
2128 __builtin_expect (l->l_flags_1 & DF_1_NODEFLIB, 0))
2130 const char *dirp = system_dirs;
2131 unsigned int cnt = 0;
2135 if (memcmp (cached, dirp, system_dirs_len[cnt]) == 0)
2137 /* The prefix matches. Don't use the entry. */
2138 cached = NULL;
2139 break;
2142 dirp += system_dirs_len[cnt] + 1;
2143 ++cnt;
2145 while (cnt < nsystem_dirs_len);
2148 if (cached != NULL)
2150 fd = open_verify (cached,
2151 &fb, loader ?: GL(dl_ns)[nsid]._ns_loaded,
2152 LA_SER_CONFIG, &found_other_class, false);
2153 if (__builtin_expect (fd != -1, 1))
2155 realname = local_strdup (cached);
2156 if (realname == NULL)
2158 __close (fd);
2159 fd = -1;
2166 /* Finally, try the default path. */
2167 if (fd == -1
2168 && ((l = loader ?: GL(dl_ns)[nsid]._ns_loaded) == NULL
2169 || __builtin_expect (!(l->l_flags_1 & DF_1_NODEFLIB), 1))
2170 && rtld_search_dirs.dirs != (void *) -1)
2171 fd = open_path (name, namelen, preloaded, &rtld_search_dirs,
2172 &realname, &fb, l, LA_SER_DEFAULT, &found_other_class);
2174 /* Add another newline when we are tracing the library loading. */
2175 if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_LIBS, 0))
2176 _dl_debug_printf ("\n");
2178 else
2180 /* The path may contain dynamic string tokens. */
2181 realname = (loader
2182 ? expand_dynamic_string_token (loader, name)
2183 : local_strdup (name));
2184 if (realname == NULL)
2185 fd = -1;
2186 else
2188 fd = open_verify (realname, &fb,
2189 loader ?: GL(dl_ns)[nsid]._ns_loaded, 0,
2190 &found_other_class, true);
2191 if (__builtin_expect (fd, 0) == -1)
2192 free (realname);
2196 #ifdef SHARED
2197 no_file:
2198 #endif
2199 /* In case the LOADER information has only been provided to get to
2200 the appropriate RUNPATH/RPATH information we do not need it
2201 anymore. */
2202 if (mode & __RTLD_CALLMAP)
2203 loader = NULL;
2205 if (__builtin_expect (fd, 0) == -1)
2207 if (trace_mode
2208 && __builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_PRELINK, 0) == 0)
2210 /* We haven't found an appropriate library. But since we
2211 are only interested in the list of libraries this isn't
2212 so severe. Fake an entry with all the information we
2213 have. */
2214 static const Elf_Symndx dummy_bucket = STN_UNDEF;
2216 /* Enter the new object in the list of loaded objects. */
2217 if ((name_copy = local_strdup (name)) == NULL
2218 || (l = _dl_new_object (name_copy, name, type, loader,
2219 mode, nsid)) == NULL)
2221 free (name_copy);
2222 _dl_signal_error (ENOMEM, name, NULL,
2223 N_("cannot create shared object descriptor"));
2225 /* Signal that this is a faked entry. */
2226 l->l_faked = 1;
2227 /* Since the descriptor is initialized with zero we do not
2228 have do this here.
2229 l->l_reserved = 0; */
2230 l->l_buckets = &dummy_bucket;
2231 l->l_nbuckets = 1;
2232 l->l_relocated = 1;
2234 return l;
2236 else if (found_other_class)
2237 _dl_signal_error (0, name, NULL,
2238 ELFW(CLASS) == ELFCLASS32
2239 ? N_("wrong ELF class: ELFCLASS64")
2240 : N_("wrong ELF class: ELFCLASS32"));
2241 else
2242 _dl_signal_error (errno, name, NULL,
2243 N_("cannot open shared object file"));
2246 void *stack_end = __libc_stack_end;
2247 return _dl_map_object_from_fd (name, fd, &fb, realname, loader, type, mode,
2248 &stack_end, nsid);
2252 void
2253 internal_function
2254 _dl_rtld_di_serinfo (struct link_map *loader, Dl_serinfo *si, bool counting)
2256 if (counting)
2258 si->dls_cnt = 0;
2259 si->dls_size = 0;
2262 unsigned int idx = 0;
2263 char *allocptr = (char *) &si->dls_serpath[si->dls_cnt];
2264 void add_path (const struct r_search_path_struct *sps, unsigned int flags)
2265 # define add_path(sps, flags) add_path(sps, 0) /* XXX */
2267 if (sps->dirs != (void *) -1)
2269 struct r_search_path_elem **dirs = sps->dirs;
2272 const struct r_search_path_elem *const r = *dirs++;
2273 if (counting)
2275 si->dls_cnt++;
2276 si->dls_size += r->dirnamelen;
2278 else
2280 Dl_serpath *const sp = &si->dls_serpath[idx++];
2281 sp->dls_name = allocptr;
2282 allocptr = __mempcpy (allocptr,
2283 r->dirname, r->dirnamelen - 1);
2284 *allocptr++ = '\0';
2285 sp->dls_flags = flags;
2288 while (*dirs != NULL);
2292 /* When the object has the RUNPATH information we don't use any RPATHs. */
2293 if (loader->l_info[DT_RUNPATH] == NULL)
2295 /* First try the DT_RPATH of the dependent object that caused NAME
2296 to be loaded. Then that object's dependent, and on up. */
2298 struct link_map *l = loader;
2301 if (cache_rpath (l, &l->l_rpath_dirs, DT_RPATH, "RPATH"))
2302 add_path (&l->l_rpath_dirs, XXX_RPATH);
2303 l = l->l_loader;
2305 while (l != NULL);
2307 /* If dynamically linked, try the DT_RPATH of the executable itself. */
2308 if (loader->l_ns == LM_ID_BASE)
2310 l = GL(dl_ns)[LM_ID_BASE]._ns_loaded;
2311 if (l != NULL && l->l_type != lt_loaded && l != loader)
2312 if (cache_rpath (l, &l->l_rpath_dirs, DT_RPATH, "RPATH"))
2313 add_path (&l->l_rpath_dirs, XXX_RPATH);
2317 /* Try the LD_LIBRARY_PATH environment variable. */
2318 add_path (&env_path_list, XXX_ENV);
2320 /* Look at the RUNPATH information for this binary. */
2321 if (cache_rpath (loader, &loader->l_runpath_dirs, DT_RUNPATH, "RUNPATH"))
2322 add_path (&loader->l_runpath_dirs, XXX_RUNPATH);
2324 /* XXX
2325 Here is where ld.so.cache gets checked, but we don't have
2326 a way to indicate that in the results for Dl_serinfo. */
2328 /* Finally, try the default path. */
2329 if (!(loader->l_flags_1 & DF_1_NODEFLIB))
2330 add_path (&rtld_search_dirs, XXX_default);
2332 if (counting)
2333 /* Count the struct size before the string area, which we didn't
2334 know before we completed dls_cnt. */
2335 si->dls_size += (char *) &si->dls_serpath[si->dls_cnt] - (char *) si;