* sysdeps/powerpc/fpu/w_sqrt.c: Add sqrtl alias.
[glibc.git] / elf / dl-load.c
blobfd80be60bcd2205f8b2f65abb72b265110353737
1 /* Map in a shared object's segments from the file.
2 Copyright (C) 1995,96,97,98,99,2000,2001,2002 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 <sys/mman.h>
30 #include <sys/param.h>
31 #include <sys/stat.h>
32 #include <sys/types.h>
33 #include "dynamic-link.h"
34 #include <abi-tag.h>
35 #include <dl-osinfo.h>
37 #include <dl-dst.h>
39 /* On some systems, no flag bits are given to specify file mapping. */
40 #ifndef MAP_FILE
41 # define MAP_FILE 0
42 #endif
44 /* The right way to map in the shared library files is MAP_COPY, which
45 makes a virtual copy of the data at the time of the mmap call; this
46 guarantees the mapped pages will be consistent even if the file is
47 overwritten. Some losing VM systems like Linux's lack MAP_COPY. All we
48 get is MAP_PRIVATE, which copies each page when it is modified; this
49 means if the file is overwritten, we may at some point get some pages
50 from the new version after starting with pages from the old version. */
51 #ifndef MAP_COPY
52 # define MAP_COPY MAP_PRIVATE
53 #endif
55 /* Some systems link their relocatable objects for another base address
56 than 0. We want to know the base address for these such that we can
57 subtract this address from the segment addresses during mapping.
58 This results in a more efficient address space usage. Defaults to
59 zero for almost all systems. */
60 #ifndef MAP_BASE_ADDR
61 # define MAP_BASE_ADDR(l) 0
62 #endif
65 #include <endian.h>
66 #if BYTE_ORDER == BIG_ENDIAN
67 # define byteorder ELFDATA2MSB
68 #elif BYTE_ORDER == LITTLE_ENDIAN
69 # define byteorder ELFDATA2LSB
70 #else
71 # error "Unknown BYTE_ORDER " BYTE_ORDER
72 # define byteorder ELFDATANONE
73 #endif
75 #define STRING(x) __STRING (x)
77 #ifdef MAP_ANON
78 /* The fd is not examined when using MAP_ANON. */
79 # define ANONFD -1
80 #else
81 int _dl_zerofd = -1;
82 # define ANONFD _dl_zerofd
83 #endif
85 /* Handle situations where we have a preferred location in memory for
86 the shared objects. */
87 #ifdef ELF_PREFERRED_ADDRESS_DATA
88 ELF_PREFERRED_ADDRESS_DATA;
89 #endif
90 #ifndef ELF_PREFERRED_ADDRESS
91 # define ELF_PREFERRED_ADDRESS(loader, maplength, mapstartpref) (mapstartpref)
92 #endif
93 #ifndef ELF_FIXED_ADDRESS
94 # define ELF_FIXED_ADDRESS(loader, mapstart) ((void) 0)
95 #endif
97 /* Type for the buffer we put the ELF header and hopefully the program
98 header. This buffer does not really have to be too large. In most
99 cases the program header follows the ELF header directly. If this
100 is not the case all bets are off and we can make the header arbitrarily
101 large and still won't get it read. This means the only question is
102 how large are the ELF and program header combined. The ELF header
103 in 64-bit files is 56 bytes long. Each program header entry is again
104 56 bytes long. I.e., even with a file which has 17 program header
105 entries we only have to read 1kB. And 17 program header entries is
106 plenty, normal files have < 10. If this heuristic should really fail
107 for some file the code in `_dl_map_object_from_fd' knows how to
108 recover. */
109 struct filebuf
111 ssize_t len;
112 char buf[1024];
115 /* This is the decomposed LD_LIBRARY_PATH search path. */
116 static struct r_search_path_struct env_path_list;
118 /* List of the hardware capabilities we might end up using. */
119 static const struct r_strlenpair *capstr;
120 static size_t ncapstr;
121 static size_t max_capstrlen;
124 /* Get the generated information about the trusted directories. */
125 #include "trusted-dirs.h"
127 static const char system_dirs[] = SYSTEM_DIRS;
128 static const size_t system_dirs_len[] =
130 SYSTEM_DIRS_LEN
132 #define nsystem_dirs_len \
133 (sizeof (system_dirs_len) / sizeof (system_dirs_len[0]))
136 /* Local version of `strdup' function. */
137 static inline char *
138 local_strdup (const char *s)
140 size_t len = strlen (s) + 1;
141 void *new = malloc (len);
143 if (new == NULL)
144 return NULL;
146 return (char *) memcpy (new, s, len);
150 static size_t
151 is_dst (const char *start, const char *name, const char *str,
152 int is_path, int secure)
154 size_t len;
155 bool is_curly = false;
157 if (name[0] == '{')
159 is_curly = true;
160 ++name;
163 len = 0;
164 while (name[len] == str[len] && name[len] != '\0')
165 ++len;
167 if (is_curly)
169 if (name[len] != '}')
170 return 0;
172 /* Point again at the beginning of the name. */
173 --name;
174 /* Skip over closing curly brace and adjust for the --name. */
175 len += 2;
177 else if (name[len] != '\0' && name[len] != '/'
178 && (!is_path || name[len] != ':'))
179 return 0;
181 if (__builtin_expect (secure, 0)
182 && ((name[len] != '\0' && (!is_path || name[len] != ':'))
183 || (name != start + 1 && (!is_path || name[-2] != ':'))))
184 return 0;
186 return len;
190 size_t
191 _dl_dst_count (const char *name, int is_path)
193 const char *const start = name;
194 size_t cnt = 0;
198 size_t len;
200 /* $ORIGIN is not expanded for SUID/GUID programs (except if it
201 is $ORIGIN alone) and it must always appear first in path. */
202 ++name;
203 if ((len = is_dst (start, name, "ORIGIN", is_path,
204 INTUSE(__libc_enable_secure))) != 0
205 || ((len = is_dst (start, name, "PLATFORM", is_path, 0))
206 != 0))
207 ++cnt;
209 name = strchr (name + len, '$');
211 while (name != NULL);
213 return cnt;
215 INTDEF (_dl_dst_count)
218 char *
219 _dl_dst_substitute (struct link_map *l, const char *name, char *result,
220 int is_path)
222 const char *const start = name;
223 char *last_elem, *wp;
225 /* Now fill the result path. While copying over the string we keep
226 track of the start of the last path element. When we come accross
227 a DST we copy over the value or (if the value is not available)
228 leave the entire path element out. */
229 last_elem = wp = result;
233 if (__builtin_expect (*name == '$', 0))
235 const char *repl = NULL;
236 size_t len;
238 ++name;
239 if ((len = is_dst (start, name, "ORIGIN", is_path,
240 INTUSE(__libc_enable_secure))) != 0)
241 repl = l->l_origin;
242 else if ((len = is_dst (start, name, "PLATFORM", is_path,
243 0)) != 0)
244 repl = GL(dl_platform);
246 if (repl != NULL && repl != (const char *) -1)
248 wp = __stpcpy (wp, repl);
249 name += len;
251 else if (len > 1)
253 /* We cannot use this path element, the value of the
254 replacement is unknown. */
255 wp = last_elem;
256 name += len;
257 while (*name != '\0' && (!is_path || *name != ':'))
258 ++name;
260 else
261 /* No DST we recognize. */
262 *wp++ = '$';
264 else
266 *wp++ = *name++;
267 if (is_path && *name == ':')
268 last_elem = wp;
271 while (*name != '\0');
273 *wp = '\0';
275 return result;
277 INTDEF (_dl_dst_substitute)
280 /* Return copy of argument with all recognized dynamic string tokens
281 ($ORIGIN and $PLATFORM for now) replaced. On some platforms it
282 might not be possible to determine the path from which the object
283 belonging to the map is loaded. In this case the path element
284 containing $ORIGIN is left out. */
285 static char *
286 expand_dynamic_string_token (struct link_map *l, const char *s)
288 /* We make two runs over the string. First we determine how large the
289 resulting string is and then we copy it over. Since this is now
290 frequently executed operation we are looking here not for performance
291 but rather for code size. */
292 size_t cnt;
293 size_t total;
294 char *result;
296 /* Determine the number of DST elements. */
297 cnt = DL_DST_COUNT (s, 1);
299 /* If we do not have to replace anything simply copy the string. */
300 if (__builtin_expect (cnt, 0) == 0)
301 return local_strdup (s);
303 /* Determine the length of the substituted string. */
304 total = DL_DST_REQUIRED (l, s, strlen (s), cnt);
306 /* Allocate the necessary memory. */
307 result = (char *) malloc (total + 1);
308 if (result == NULL)
309 return NULL;
311 return INTUSE(_dl_dst_substitute) (l, s, result, 1);
315 /* Add `name' to the list of names for a particular shared object.
316 `name' is expected to have been allocated with malloc and will
317 be freed if the shared object already has this name.
318 Returns false if the object already had this name. */
319 static void
320 internal_function
321 add_name_to_object (struct link_map *l, const char *name)
323 struct libname_list *lnp, *lastp;
324 struct libname_list *newname;
325 size_t name_len;
327 lastp = NULL;
328 for (lnp = l->l_libname; lnp != NULL; lastp = lnp, lnp = lnp->next)
329 if (strcmp (name, lnp->name) == 0)
330 return;
332 name_len = strlen (name) + 1;
333 newname = (struct libname_list *) malloc (sizeof *newname + name_len);
334 if (newname == NULL)
336 /* No more memory. */
337 INTUSE(_dl_signal_error) (ENOMEM, name, NULL,
338 N_("cannot allocate name record"));
339 return;
341 /* The object should have a libname set from _dl_new_object. */
342 assert (lastp != NULL);
344 newname->name = memcpy (newname + 1, name, name_len);
345 newname->next = NULL;
346 newname->dont_free = 0;
347 lastp->next = newname;
350 /* Standard search directories. */
351 static struct r_search_path_struct rtld_search_dirs;
353 static size_t max_dirnamelen;
355 static inline struct r_search_path_elem **
356 fillin_rpath (char *rpath, struct r_search_path_elem **result, const char *sep,
357 int check_trusted, const char *what, const char *where)
359 char *cp;
360 size_t nelems = 0;
362 while ((cp = __strsep (&rpath, sep)) != NULL)
364 struct r_search_path_elem *dirp;
365 size_t len = strlen (cp);
367 /* `strsep' can pass an empty string. This has to be
368 interpreted as `use the current directory'. */
369 if (len == 0)
371 static const char curwd[] = "./";
372 cp = (char *) curwd;
375 /* Remove trailing slashes (except for "/"). */
376 while (len > 1 && cp[len - 1] == '/')
377 --len;
379 /* Now add one if there is none so far. */
380 if (len > 0 && cp[len - 1] != '/')
381 cp[len++] = '/';
383 /* Make sure we don't use untrusted directories if we run SUID. */
384 if (__builtin_expect (check_trusted, 0))
386 const char *trun = system_dirs;
387 size_t idx;
388 int unsecure = 1;
390 /* All trusted directories must be complete names. */
391 if (cp[0] == '/')
393 for (idx = 0; idx < nsystem_dirs_len; ++idx)
395 if (len == system_dirs_len[idx]
396 && memcmp (trun, cp, len) == 0)
398 /* Found it. */
399 unsecure = 0;
400 break;
403 trun += system_dirs_len[idx] + 1;
407 if (unsecure)
408 /* Simply drop this directory. */
409 continue;
412 /* See if this directory is already known. */
413 for (dirp = GL(dl_all_dirs); dirp != NULL; dirp = dirp->next)
414 if (dirp->dirnamelen == len && memcmp (cp, dirp->dirname, len) == 0)
415 break;
417 if (dirp != NULL)
419 /* It is available, see whether it's on our own list. */
420 size_t cnt;
421 for (cnt = 0; cnt < nelems; ++cnt)
422 if (result[cnt] == dirp)
423 break;
425 if (cnt == nelems)
426 result[nelems++] = dirp;
428 else
430 size_t cnt;
431 enum r_dir_status init_val;
432 size_t where_len = where ? strlen (where) + 1 : 0;
434 /* It's a new directory. Create an entry and add it. */
435 dirp = (struct r_search_path_elem *)
436 malloc (sizeof (*dirp) + ncapstr * sizeof (enum r_dir_status)
437 + where_len + len + 1);
438 if (dirp == NULL)
439 INTUSE(_dl_signal_error) (ENOMEM, NULL, NULL,
440 N_("cannot create cache for search path"));
442 dirp->dirname = ((char *) dirp + sizeof (*dirp)
443 + ncapstr * sizeof (enum r_dir_status));
444 *((char *) __mempcpy ((char *) dirp->dirname, cp, len)) = '\0';
445 dirp->dirnamelen = len;
447 if (len > max_dirnamelen)
448 max_dirnamelen = len;
450 /* We have to make sure all the relative directories are
451 never ignored. The current directory might change and
452 all our saved information would be void. */
453 init_val = cp[0] != '/' ? existing : unknown;
454 for (cnt = 0; cnt < ncapstr; ++cnt)
455 dirp->status[cnt] = init_val;
457 dirp->what = what;
458 if (__builtin_expect (where != NULL, 1))
459 dirp->where = memcpy ((char *) dirp + sizeof (*dirp) + len + 1
460 + (ncapstr * sizeof (enum r_dir_status)),
461 where, where_len);
462 else
463 dirp->where = NULL;
465 dirp->next = GL(dl_all_dirs);
466 GL(dl_all_dirs) = dirp;
468 /* Put it in the result array. */
469 result[nelems++] = dirp;
473 /* Terminate the array. */
474 result[nelems] = NULL;
476 return result;
480 static void
481 internal_function
482 decompose_rpath (struct r_search_path_struct *sps,
483 const char *rpath, struct link_map *l, const char *what)
485 /* Make a copy we can work with. */
486 const char *where = l->l_name;
487 char *copy;
488 char *cp;
489 struct r_search_path_elem **result;
490 size_t nelems;
491 /* Initialize to please the compiler. */
492 const char *errstring = NULL;
494 /* First see whether we must forget the RUNPATH and RPATH from this
495 object. */
496 if (__builtin_expect (GL(dl_inhibit_rpath) != NULL, 0)
497 && !INTUSE(__libc_enable_secure))
499 const char *inhp = GL(dl_inhibit_rpath);
503 const char *wp = where;
505 while (*inhp == *wp && *wp != '\0')
507 ++inhp;
508 ++wp;
511 if (*wp == '\0' && (*inhp == '\0' || *inhp == ':'))
513 /* This object is on the list of objects for which the
514 RUNPATH and RPATH must not be used. */
515 result = (struct r_search_path_elem **)
516 malloc (sizeof (*result));
517 if (result == NULL)
519 signal_error_cache:
520 errstring = N_("cannot create cache for search path");
521 signal_error:
522 INTUSE(_dl_signal_error) (ENOMEM, NULL, NULL, errstring);
525 result[0] = NULL;
527 sps->dirs = result;
528 sps->malloced = 1;
530 return;
533 while (*inhp != '\0')
534 if (*inhp++ == ':')
535 break;
537 while (*inhp != '\0');
540 /* Make a writable copy. At the same time expand possible dynamic
541 string tokens. */
542 copy = expand_dynamic_string_token (l, rpath);
543 if (copy == NULL)
545 errstring = N_("cannot create RUNPATH/RPATH copy");
546 goto signal_error;
549 /* Count the number of necessary elements in the result array. */
550 nelems = 0;
551 for (cp = copy; *cp != '\0'; ++cp)
552 if (*cp == ':')
553 ++nelems;
555 /* Allocate room for the result. NELEMS + 1 is an upper limit for the
556 number of necessary entries. */
557 result = (struct r_search_path_elem **) malloc ((nelems + 1 + 1)
558 * sizeof (*result));
559 if (result == NULL)
560 goto signal_error_cache;
562 fillin_rpath (copy, result, ":", 0, what, where);
564 /* Free the copied RPATH string. `fillin_rpath' make own copies if
565 necessary. */
566 free (copy);
568 sps->dirs = result;
569 /* The caller will change this value if we haven't used a real malloc. */
570 sps->malloced = 1;
574 void
575 internal_function
576 _dl_init_paths (const char *llp)
578 size_t idx;
579 const char *strp;
580 struct r_search_path_elem *pelem, **aelem;
581 size_t round_size;
582 #ifdef SHARED
583 struct link_map *l;
584 #endif
585 /* Initialize to please the compiler. */
586 const char *errstring = NULL;
588 /* Fill in the information about the application's RPATH and the
589 directories addressed by the LD_LIBRARY_PATH environment variable. */
591 /* Get the capabilities. */
592 capstr = _dl_important_hwcaps (GL(dl_platform), GL(dl_platformlen),
593 &ncapstr, &max_capstrlen);
595 /* First set up the rest of the default search directory entries. */
596 aelem = rtld_search_dirs.dirs = (struct r_search_path_elem **)
597 malloc ((nsystem_dirs_len + 1) * sizeof (struct r_search_path_elem *));
598 if (rtld_search_dirs.dirs == NULL)
600 errstring = N_("cannot create search path array");
601 signal_error:
602 INTUSE(_dl_signal_error) (ENOMEM, NULL, NULL, errstring);
605 round_size = ((2 * sizeof (struct r_search_path_elem) - 1
606 + ncapstr * sizeof (enum r_dir_status))
607 / sizeof (struct r_search_path_elem));
609 rtld_search_dirs.dirs[0] = (struct r_search_path_elem *)
610 malloc ((sizeof (system_dirs) / sizeof (system_dirs[0]))
611 * round_size * sizeof (struct r_search_path_elem));
612 if (rtld_search_dirs.dirs[0] == NULL)
614 errstring = N_("cannot create cache for search path");
615 goto signal_error;
618 rtld_search_dirs.malloced = 0;
619 pelem = GL(dl_all_dirs) = rtld_search_dirs.dirs[0];
620 strp = system_dirs;
621 idx = 0;
625 size_t cnt;
627 *aelem++ = pelem;
629 pelem->what = "system search path";
630 pelem->where = NULL;
632 pelem->dirname = strp;
633 pelem->dirnamelen = system_dirs_len[idx];
634 strp += system_dirs_len[idx] + 1;
636 /* System paths must be absolute. */
637 assert (pelem->dirname[0] == '/');
638 for (cnt = 0; cnt < ncapstr; ++cnt)
639 pelem->status[cnt] = unknown;
641 pelem->next = (++idx == nsystem_dirs_len ? NULL : (pelem + round_size));
643 pelem += round_size;
645 while (idx < nsystem_dirs_len);
647 max_dirnamelen = SYSTEM_DIRS_MAX_LEN;
648 *aelem = NULL;
650 #ifdef SHARED
651 /* This points to the map of the main object. */
652 l = GL(dl_loaded);
653 if (l != NULL)
655 assert (l->l_type != lt_loaded);
657 if (l->l_info[DT_RUNPATH])
659 /* Allocate room for the search path and fill in information
660 from RUNPATH. */
661 decompose_rpath (&l->l_runpath_dirs,
662 (const void *) (D_PTR (l, l_info[DT_STRTAB])
663 + l->l_info[DT_RUNPATH]->d_un.d_val),
664 l, "RUNPATH");
666 /* The RPATH is ignored. */
667 l->l_rpath_dirs.dirs = (void *) -1;
669 else
671 l->l_runpath_dirs.dirs = (void *) -1;
673 if (l->l_info[DT_RPATH])
675 /* Allocate room for the search path and fill in information
676 from RPATH. */
677 decompose_rpath (&l->l_rpath_dirs,
678 (const void *) (D_PTR (l, l_info[DT_STRTAB])
679 + l->l_info[DT_RPATH]->d_un.d_val),
680 l, "RPATH");
681 l->l_rpath_dirs.malloced = 0;
683 else
684 l->l_rpath_dirs.dirs = (void *) -1;
687 #endif /* SHARED */
689 if (llp != NULL && *llp != '\0')
691 size_t nllp;
692 const char *cp = llp;
693 char *llp_tmp = strdupa (llp);
695 /* Decompose the LD_LIBRARY_PATH contents. First determine how many
696 elements it has. */
697 nllp = 1;
698 while (*cp)
700 if (*cp == ':' || *cp == ';')
701 ++nllp;
702 ++cp;
705 env_path_list.dirs = (struct r_search_path_elem **)
706 malloc ((nllp + 1) * sizeof (struct r_search_path_elem *));
707 if (env_path_list.dirs == NULL)
709 errstring = N_("cannot create cache for search path");
710 goto signal_error;
713 (void) fillin_rpath (llp_tmp, env_path_list.dirs, ":;",
714 INTUSE(__libc_enable_secure), "LD_LIBRARY_PATH",
715 NULL);
717 if (env_path_list.dirs[0] == NULL)
719 free (env_path_list.dirs);
720 env_path_list.dirs = (void *) -1;
723 env_path_list.malloced = 0;
725 else
726 env_path_list.dirs = (void *) -1;
728 /* Remember the last search directory added at startup. */
729 GL(dl_init_all_dirs) = GL(dl_all_dirs);
733 /* Think twice before changing anything in this function. It is placed
734 here and prepared using the `alloca' magic to prevent it from being
735 inlined. The function is only called in case of an error. But then
736 performance does not count. The function used to be "inlinable" and
737 the compiled did so all the time. This increased the code size for
738 absolutely no good reason. */
739 static void
740 __attribute__ ((noreturn))
741 lose (int code, int fd, const char *name, char *realname, struct link_map *l,
742 const char *msg)
744 /* The use of `alloca' here looks ridiculous but it helps. The goal
745 is to avoid the function from being inlined. There is no official
746 way to do this so we use this trick. gcc never inlines functions
747 which use `alloca'. */
748 int *a = (int *) alloca (sizeof (int));
749 a[0] = fd;
750 /* The file might already be closed. */
751 if (a[0] != -1)
752 (void) __close (a[0]);
753 if (l != NULL)
755 /* Remove the stillborn object from the list and free it. */
756 assert (l->l_next == NULL);
757 #ifndef SHARED
758 if (l->l_prev == NULL)
759 /* No other module loaded. */
760 GL(dl_loaded) = NULL;
761 else
762 #endif
763 l->l_prev->l_next = NULL;
764 --GL(dl_nloaded);
765 free (l);
767 free (realname);
768 INTUSE(_dl_signal_error) (code, name, NULL, msg);
772 /* Map in the shared object NAME, actually located in REALNAME, and already
773 opened on FD. */
775 #ifndef EXTERNAL_MAP_FROM_FD
776 static
777 #endif
778 struct link_map *
779 _dl_map_object_from_fd (const char *name, int fd, struct filebuf *fbp,
780 char *realname, struct link_map *loader, int l_type,
781 int mode)
783 struct link_map *l = NULL;
784 const ElfW(Ehdr) *header;
785 const ElfW(Phdr) *phdr;
786 const ElfW(Phdr) *ph;
787 size_t maplength;
788 int type;
789 struct stat64 st;
790 /* Initialize to keep the compiler happy. */
791 const char *errstring = NULL;
792 int errval = 0;
794 /* Get file information. */
795 if (__builtin_expect (__fxstat64 (_STAT_VER, fd, &st) < 0, 0))
797 errstring = N_("cannot stat shared object");
798 call_lose_errno:
799 errval = errno;
800 call_lose:
801 lose (errval, fd, name, realname, l, errstring);
804 /* Look again to see if the real name matched another already loaded. */
805 for (l = GL(dl_loaded); l; l = l->l_next)
806 if (l->l_ino == st.st_ino && l->l_dev == st.st_dev)
808 /* The object is already loaded.
809 Just bump its reference count and return it. */
810 __close (fd);
812 /* If the name is not in the list of names for this object add
813 it. */
814 free (realname);
815 add_name_to_object (l, name);
817 return l;
820 if (mode & RTLD_NOLOAD)
821 /* We are not supposed to load the object unless it is already
822 loaded. So return now. */
823 return NULL;
825 /* Print debugging message. */
826 if (__builtin_expect (GL(dl_debug_mask) & DL_DEBUG_FILES, 0))
827 INTUSE(_dl_debug_printf) ("file=%s; generating link map\n", name);
829 /* This is the ELF header. We read it in `open_verify'. */
830 header = (void *) fbp->buf;
832 #ifndef MAP_ANON
833 # define MAP_ANON 0
834 if (_dl_zerofd == -1)
836 _dl_zerofd = _dl_sysdep_open_zero_fill ();
837 if (_dl_zerofd == -1)
839 __close (fd);
840 INTUSE(_dl_signal_error) (errno, NULL, NULL,
841 N_("cannot open zero fill device"));
844 #endif
846 /* Enter the new object in the list of loaded objects. */
847 l = _dl_new_object (realname, name, l_type, loader);
848 if (__builtin_expect (! l, 0))
850 errstring = N_("cannot create shared object descriptor");
851 goto call_lose_errno;
854 /* Extract the remaining details we need from the ELF header
855 and then read in the program header table. */
856 l->l_entry = header->e_entry;
857 type = header->e_type;
858 l->l_phnum = header->e_phnum;
860 maplength = header->e_phnum * sizeof (ElfW(Phdr));
861 if (header->e_phoff + maplength <= fbp->len)
862 phdr = (void *) (fbp->buf + header->e_phoff);
863 else
865 phdr = alloca (maplength);
866 __lseek (fd, header->e_phoff, SEEK_SET);
867 if (__libc_read (fd, (void *) phdr, maplength) != maplength)
869 errstring = N_("cannot read file data");
870 goto call_lose_errno;
875 /* Scan the program header table, collecting its load commands. */
876 struct loadcmd
878 ElfW(Addr) mapstart, mapend, dataend, allocend;
879 off_t mapoff;
880 int prot;
881 } loadcmds[l->l_phnum], *c;
882 size_t nloadcmds = 0;
884 /* The struct is initialized to zero so this is not necessary:
885 l->l_ld = 0;
886 l->l_phdr = 0;
887 l->l_addr = 0; */
888 for (ph = phdr; ph < &phdr[l->l_phnum]; ++ph)
889 switch (ph->p_type)
891 /* These entries tell us where to find things once the file's
892 segments are mapped in. We record the addresses it says
893 verbatim, and later correct for the run-time load address. */
894 case PT_DYNAMIC:
895 l->l_ld = (void *) ph->p_vaddr;
896 l->l_ldnum = ph->p_memsz / sizeof (ElfW(Dyn));
897 break;
899 case PT_PHDR:
900 l->l_phdr = (void *) ph->p_vaddr;
901 break;
903 case PT_LOAD:
904 /* A load command tells us to map in part of the file.
905 We record the load commands and process them all later. */
906 if ((ph->p_align & (GL(dl_pagesize) - 1)) != 0)
908 errstring = N_("ELF load command alignment not page-aligned");
909 goto call_lose;
911 if (((ph->p_vaddr - ph->p_offset) & (ph->p_align - 1)) != 0)
913 errstring
914 = N_("ELF load command address/offset not properly aligned");
915 goto call_lose;
919 struct loadcmd *c = &loadcmds[nloadcmds++];
920 c->mapstart = ph->p_vaddr & ~(ph->p_align - 1);
921 c->mapend = ((ph->p_vaddr + ph->p_filesz + GL(dl_pagesize) - 1)
922 & ~(GL(dl_pagesize) - 1));
923 c->dataend = ph->p_vaddr + ph->p_filesz;
924 c->allocend = ph->p_vaddr + ph->p_memsz;
925 c->mapoff = ph->p_offset & ~(ph->p_align - 1);
927 /* Optimize a common case. */
928 #if (PF_R | PF_W | PF_X) == 7 && (PROT_READ | PROT_WRITE | PROT_EXEC) == 7
929 c->prot = (PF_TO_PROT
930 >> ((ph->p_flags & (PF_R | PF_W | PF_X)) * 4)) & 0xf;
931 #else
932 c->prot = 0;
933 if (ph->p_flags & PF_R)
934 c->prot |= PROT_READ;
935 if (ph->p_flags & PF_W)
936 c->prot |= PROT_WRITE;
937 if (ph->p_flags & PF_X)
938 c->prot |= PROT_EXEC;
939 #endif
941 break;
943 #ifdef USE_TLS
944 case PT_TLS:
945 if (ph->p_memsz > 0)
947 l->l_tls_blocksize = ph->p_memsz;
948 l->l_tls_align = ph->p_align;
949 l->l_tls_initimage_size = ph->p_filesz;
950 /* Since we don't know the load address yet only store the
951 offset. We will adjust it later. */
952 l->l_tls_initimage = (void *) ph->p_offset;
954 /* Assign the next available module ID. */
955 l->l_tls_modid = _dl_next_tls_modid ();
957 break;
958 #endif
961 /* Now process the load commands and map segments into memory. */
962 c = loadcmds;
964 /* Length of the sections to be loaded. */
965 maplength = loadcmds[nloadcmds - 1].allocend - c->mapstart;
967 if (__builtin_expect (type, ET_DYN) == ET_DYN)
969 /* This is a position-independent shared object. We can let the
970 kernel map it anywhere it likes, but we must have space for all
971 the segments in their specified positions relative to the first.
972 So we map the first segment without MAP_FIXED, but with its
973 extent increased to cover all the segments. Then we remove
974 access from excess portion, and there is known sufficient space
975 there to remap from the later segments.
977 As a refinement, sometimes we have an address that we would
978 prefer to map such objects at; but this is only a preference,
979 the OS can do whatever it likes. */
980 ElfW(Addr) mappref;
981 mappref = (ELF_PREFERRED_ADDRESS (loader, maplength, c->mapstart)
982 - MAP_BASE_ADDR (l));
984 /* Remember which part of the address space this object uses. */
985 l->l_map_start = (ElfW(Addr)) __mmap ((void *) mappref, maplength,
986 c->prot, MAP_COPY | MAP_FILE,
987 fd, c->mapoff);
988 if ((void *) l->l_map_start == MAP_FAILED)
990 map_error:
991 errstring = N_("failed to map segment from shared object");
992 goto call_lose_errno;
995 l->l_map_end = l->l_map_start + maplength;
996 l->l_addr = l->l_map_start - c->mapstart;
998 /* Change protection on the excess portion to disallow all access;
999 the portions we do not remap later will be inaccessible as if
1000 unallocated. Then jump into the normal segment-mapping loop to
1001 handle the portion of the segment past the end of the file
1002 mapping. */
1003 __mprotect ((caddr_t) (l->l_addr + c->mapend),
1004 loadcmds[nloadcmds - 1].allocend - c->mapend,
1005 PROT_NONE);
1007 goto postmap;
1009 else
1011 /* This object is loaded at a fixed address. This must never
1012 happen for objects loaded with dlopen(). */
1013 if (__builtin_expect (mode & __RTLD_DLOPEN, 0))
1015 errstring = N_("cannot dynamically load executable");
1016 goto call_lose;
1019 /* Notify ELF_PREFERRED_ADDRESS that we have to load this one
1020 fixed. */
1021 ELF_FIXED_ADDRESS (loader, c->mapstart);
1024 /* Remember which part of the address space this object uses. */
1025 l->l_map_start = c->mapstart + l->l_addr;
1026 l->l_map_end = l->l_map_start + maplength;
1028 while (c < &loadcmds[nloadcmds])
1030 if (c->mapend > c->mapstart
1031 /* Map the segment contents from the file. */
1032 && (__mmap ((void *) (l->l_addr + c->mapstart),
1033 c->mapend - c->mapstart, c->prot,
1034 MAP_FIXED | MAP_COPY | MAP_FILE, fd, c->mapoff)
1035 == MAP_FAILED))
1036 goto map_error;
1038 postmap:
1039 if (l->l_phdr == 0
1040 && c->mapoff <= header->e_phoff
1041 && (c->mapend - c->mapstart + c->mapoff
1042 >= header->e_phoff + header->e_phnum * sizeof (ElfW(Phdr))))
1043 /* Found the program header in this segment. */
1044 l->l_phdr = (void *) (c->mapstart + header->e_phoff - c->mapoff);
1046 if (c->allocend > c->dataend)
1048 /* Extra zero pages should appear at the end of this segment,
1049 after the data mapped from the file. */
1050 ElfW(Addr) zero, zeroend, zeropage;
1052 zero = l->l_addr + c->dataend;
1053 zeroend = l->l_addr + c->allocend;
1054 zeropage = ((zero + GL(dl_pagesize) - 1)
1055 & ~(GL(dl_pagesize) - 1));
1057 if (zeroend < zeropage)
1058 /* All the extra data is in the last page of the segment.
1059 We can just zero it. */
1060 zeropage = zeroend;
1062 if (zeropage > zero)
1064 /* Zero the final part of the last page of the segment. */
1065 if ((c->prot & PROT_WRITE) == 0)
1067 /* Dag nab it. */
1068 if (__mprotect ((caddr_t) (zero & ~(GL(dl_pagesize) - 1)),
1069 GL(dl_pagesize), c->prot|PROT_WRITE) < 0)
1071 errstring = N_("cannot change memory protections");
1072 goto call_lose_errno;
1075 memset ((void *) zero, '\0', zeropage - zero);
1076 if ((c->prot & PROT_WRITE) == 0)
1077 __mprotect ((caddr_t) (zero & ~(GL(dl_pagesize) - 1)),
1078 GL(dl_pagesize), c->prot);
1081 if (zeroend > zeropage)
1083 /* Map the remaining zero pages in from the zero fill FD. */
1084 caddr_t mapat;
1085 mapat = __mmap ((caddr_t) zeropage, zeroend - zeropage,
1086 c->prot, MAP_ANON|MAP_PRIVATE|MAP_FIXED,
1087 ANONFD, 0);
1088 if (mapat == MAP_FAILED)
1090 errstring = N_("cannot map zero-fill pages");
1091 goto call_lose_errno;
1096 ++c;
1099 if (l->l_phdr == NULL)
1101 /* The program header is not contained in any of the segments.
1102 We have to allocate memory ourself and copy it over from
1103 out temporary place. */
1104 ElfW(Phdr) *newp = (ElfW(Phdr) *) malloc (header->e_phnum
1105 * sizeof (ElfW(Phdr)));
1106 if (newp == NULL)
1108 errstring = N_("cannot allocate memory for program header");
1109 goto call_lose_errno;
1112 l->l_phdr = memcpy (newp, phdr,
1113 (header->e_phnum * sizeof (ElfW(Phdr))));
1114 l->l_phdr_allocated = 1;
1116 else
1117 /* Adjust the PT_PHDR value by the runtime load address. */
1118 (ElfW(Addr)) l->l_phdr += l->l_addr;
1121 #ifdef USE_TLS
1122 /* Adjust the address of the TLS initialization image. */
1123 if (l->l_tls_initimage != NULL)
1124 l->l_tls_initimage = (char *) l->l_tls_initimage + l->l_map_start;
1125 #endif
1127 /* We are done mapping in the file. We no longer need the descriptor. */
1128 __close (fd);
1129 /* Signal that we closed the file. */
1130 fd = -1;
1132 if (l->l_type == lt_library && type == ET_EXEC)
1133 l->l_type = lt_executable;
1135 if (l->l_ld == 0)
1137 if (type == ET_DYN)
1139 errstring = N_("object file has no dynamic section");
1140 goto call_lose;
1143 else
1144 (ElfW(Addr)) l->l_ld += l->l_addr;
1146 l->l_entry += l->l_addr;
1148 if (__builtin_expect (GL(dl_debug_mask) & DL_DEBUG_FILES, 0))
1149 INTUSE(_dl_debug_printf) ("\
1150 dynamic: 0x%0*lx base: 0x%0*lx size: 0x%0*Zx\n\
1151 entry: 0x%0*lx phdr: 0x%0*lx phnum: %*u\n\n",
1152 (int) sizeof (void *) * 2,
1153 (unsigned long int) l->l_ld,
1154 (int) sizeof (void *) * 2,
1155 (unsigned long int) l->l_addr,
1156 (int) sizeof (void *) * 2, maplength,
1157 (int) sizeof (void *) * 2,
1158 (unsigned long int) l->l_entry,
1159 (int) sizeof (void *) * 2,
1160 (unsigned long int) l->l_phdr,
1161 (int) sizeof (void *) * 2, l->l_phnum);
1163 elf_get_dynamic_info (l);
1165 /* Make sure we are dlopen()ing an object which has the DF_1_NOOPEN
1166 flag set. */
1167 if ((__builtin_expect (l->l_flags_1 & DF_1_NOOPEN, 0)
1168 #ifdef USE_TLS
1169 || __builtin_expect (l->l_flags & DF_STATIC_TLS, 0)
1170 #endif
1172 && (mode & __RTLD_DLOPEN))
1174 /* We are not supposed to load this object. Free all resources. */
1175 __munmap ((void *) l->l_map_start, l->l_map_end - l->l_map_start);
1177 if (!l->l_libname->dont_free)
1178 free (l->l_libname);
1180 if (l->l_phdr_allocated)
1181 free ((void *) l->l_phdr);
1183 errstring = N_("shared object cannot be dlopen()ed");
1184 goto call_lose;
1187 if (l->l_info[DT_HASH])
1188 _dl_setup_hash (l);
1190 /* If this object has DT_SYMBOLIC set modify now its scope. We don't
1191 have to do this for the main map. */
1192 if (__builtin_expect (l->l_info[DT_SYMBOLIC] != NULL, 0)
1193 && &l->l_searchlist != l->l_scope[0])
1195 /* Create an appropriate searchlist. It contains only this map.
1197 XXX This is the definition of DT_SYMBOLIC in SysVr4. The old
1198 GNU ld.so implementation had a different interpretation which
1199 is more reasonable. We are prepared to add this possibility
1200 back as part of a GNU extension of the ELF format. */
1201 l->l_symbolic_searchlist.r_list =
1202 (struct link_map **) malloc (sizeof (struct link_map *));
1204 if (l->l_symbolic_searchlist.r_list == NULL)
1206 errstring = N_("cannot create searchlist");
1207 goto call_lose_errno;
1210 l->l_symbolic_searchlist.r_list[0] = l;
1211 l->l_symbolic_searchlist.r_nlist = 1;
1213 /* Now move the existing entries one back. */
1214 memmove (&l->l_scope[1], &l->l_scope[0],
1215 (l->l_scope_max - 1) * sizeof (l->l_scope[0]));
1217 /* Now add the new entry. */
1218 l->l_scope[0] = &l->l_symbolic_searchlist;
1221 /* Remember whether this object must be initialized first. */
1222 if (l->l_flags_1 & DF_1_INITFIRST)
1223 GL(dl_initfirst) = l;
1225 /* Finally the file information. */
1226 l->l_dev = st.st_dev;
1227 l->l_ino = st.st_ino;
1229 /* When we profile the SONAME might be needed for something else but
1230 loading. Add it right away. */
1231 if (__builtin_expect (GL(dl_profile) != NULL, 0)
1232 && l->l_info[DT_SONAME] != NULL)
1233 add_name_to_object (l, ((const char *) D_PTR (l, l_info[DT_STRTAB])
1234 + l->l_info[DT_SONAME]->d_un.d_val));
1236 return l;
1239 /* Print search path. */
1240 static void
1241 print_search_path (struct r_search_path_elem **list,
1242 const char *what, const char *name)
1244 char buf[max_dirnamelen + max_capstrlen];
1245 int first = 1;
1247 INTUSE(_dl_debug_printf) (" search path=");
1249 while (*list != NULL && (*list)->what == what) /* Yes, ==. */
1251 char *endp = __mempcpy (buf, (*list)->dirname, (*list)->dirnamelen);
1252 size_t cnt;
1254 for (cnt = 0; cnt < ncapstr; ++cnt)
1255 if ((*list)->status[cnt] != nonexisting)
1257 char *cp = __mempcpy (endp, capstr[cnt].str, capstr[cnt].len);
1258 if (cp == buf || (cp == buf + 1 && buf[0] == '/'))
1259 cp[0] = '\0';
1260 else
1261 cp[-1] = '\0';
1263 _dl_debug_printf_c (first ? "%s" : ":%s", buf);
1264 first = 0;
1267 ++list;
1270 if (name != NULL)
1271 _dl_debug_printf_c ("\t\t(%s from file %s)\n", what,
1272 name[0] ? name : rtld_progname);
1273 else
1274 _dl_debug_printf_c ("\t\t(%s)\n", what);
1277 /* Open a file and verify it is an ELF file for this architecture. We
1278 ignore only ELF files for other architectures. Non-ELF files and
1279 ELF files with different header information cause fatal errors since
1280 this could mean there is something wrong in the installation and the
1281 user might want to know about this. */
1282 static int
1283 open_verify (const char *name, struct filebuf *fbp)
1285 /* This is the expected ELF header. */
1286 #define ELF32_CLASS ELFCLASS32
1287 #define ELF64_CLASS ELFCLASS64
1288 #ifndef VALID_ELF_HEADER
1289 # define VALID_ELF_HEADER(hdr,exp,size) (memcmp (hdr, exp, size) == 0)
1290 # define VALID_ELF_OSABI(osabi) (osabi == ELFOSABI_SYSV)
1291 # define VALID_ELF_ABIVERSION(ver) (ver == 0)
1292 #endif
1293 static const unsigned char expected[EI_PAD] =
1295 [EI_MAG0] = ELFMAG0,
1296 [EI_MAG1] = ELFMAG1,
1297 [EI_MAG2] = ELFMAG2,
1298 [EI_MAG3] = ELFMAG3,
1299 [EI_CLASS] = ELFW(CLASS),
1300 [EI_DATA] = byteorder,
1301 [EI_VERSION] = EV_CURRENT,
1302 [EI_OSABI] = ELFOSABI_SYSV,
1303 [EI_ABIVERSION] = 0
1305 static const struct
1307 ElfW(Word) vendorlen;
1308 ElfW(Word) datalen;
1309 ElfW(Word) type;
1310 char vendor[4];
1311 } expected_note = { 4, 16, 1, "GNU" };
1312 int fd;
1313 /* Initialize it to make the compiler happy. */
1314 const char *errstring = NULL;
1315 int errval = 0;
1317 /* Open the file. We always open files read-only. */
1318 fd = __open (name, O_RDONLY);
1319 if (fd != -1)
1321 ElfW(Ehdr) *ehdr;
1322 ElfW(Phdr) *phdr, *ph;
1323 ElfW(Word) *abi_note, abi_note_buf[8];
1324 unsigned int osversion;
1325 size_t maplength;
1327 /* We successfully openened the file. Now verify it is a file
1328 we can use. */
1329 __set_errno (0);
1330 fbp->len = __libc_read (fd, fbp->buf, sizeof (fbp->buf));
1332 /* This is where the ELF header is loaded. */
1333 assert (sizeof (fbp->buf) > sizeof (ElfW(Ehdr)));
1334 ehdr = (ElfW(Ehdr) *) fbp->buf;
1336 /* Now run the tests. */
1337 if (__builtin_expect (fbp->len < (ssize_t) sizeof (ElfW(Ehdr)), 0))
1339 errval = errno;
1340 errstring = (errval == 0
1341 ? N_("file too short") : N_("cannot read file data"));
1342 call_lose:
1343 lose (errval, fd, name, NULL, NULL, errstring);
1346 /* See whether the ELF header is what we expect. */
1347 if (__builtin_expect (! VALID_ELF_HEADER (ehdr->e_ident, expected,
1348 EI_PAD), 0))
1350 /* Something is wrong. */
1351 if (*(Elf32_Word *) &ehdr->e_ident !=
1352 #if BYTE_ORDER == LITTLE_ENDIAN
1353 ((ELFMAG0 << (EI_MAG0 * 8)) |
1354 (ELFMAG1 << (EI_MAG1 * 8)) |
1355 (ELFMAG2 << (EI_MAG2 * 8)) |
1356 (ELFMAG3 << (EI_MAG3 * 8)))
1357 #else
1358 ((ELFMAG0 << (EI_MAG3 * 8)) |
1359 (ELFMAG1 << (EI_MAG2 * 8)) |
1360 (ELFMAG2 << (EI_MAG1 * 8)) |
1361 (ELFMAG3 << (EI_MAG0 * 8)))
1362 #endif
1364 errstring = N_("invalid ELF header");
1365 else if (ehdr->e_ident[EI_CLASS] != ELFW(CLASS))
1366 /* This is not a fatal error. On architectures where
1367 32-bit and 64-bit binaries can be run this might
1368 happen. */
1369 goto close_and_out;
1370 else if (ehdr->e_ident[EI_DATA] != byteorder)
1372 if (BYTE_ORDER == BIG_ENDIAN)
1373 errstring = N_("ELF file data encoding not big-endian");
1374 else
1375 errstring = N_("ELF file data encoding not little-endian");
1377 else if (ehdr->e_ident[EI_VERSION] != EV_CURRENT)
1378 errstring
1379 = N_("ELF file version ident does not match current one");
1380 /* XXX We should be able so set system specific versions which are
1381 allowed here. */
1382 else if (!VALID_ELF_OSABI (ehdr->e_ident[EI_OSABI]))
1383 errstring = N_("ELF file OS ABI invalid");
1384 else if (!VALID_ELF_ABIVERSION (ehdr->e_ident[EI_ABIVERSION]))
1385 errstring = N_("ELF file ABI version invalid");
1386 else
1387 /* Otherwise we don't know what went wrong. */
1388 errstring = N_("internal error");
1390 goto call_lose;
1393 if (__builtin_expect (ehdr->e_version, EV_CURRENT) != EV_CURRENT)
1395 errstring = N_("ELF file version does not match current one");
1396 goto call_lose;
1398 if (! __builtin_expect (elf_machine_matches_host (ehdr), 1))
1399 goto close_and_out;
1400 else if (__builtin_expect (ehdr->e_phentsize, sizeof (ElfW(Phdr)))
1401 != sizeof (ElfW(Phdr)))
1403 errstring = N_("ELF file's phentsize not the expected size");
1404 goto call_lose;
1406 else if (__builtin_expect (ehdr->e_type, ET_DYN) != ET_DYN
1407 && __builtin_expect (ehdr->e_type, ET_EXEC) != ET_EXEC)
1409 errstring = N_("only ET_DYN and ET_EXEC can be loaded");
1410 goto call_lose;
1413 maplength = ehdr->e_phnum * sizeof (ElfW(Phdr));
1414 if (ehdr->e_phoff + maplength <= fbp->len)
1415 phdr = (void *) (fbp->buf + ehdr->e_phoff);
1416 else
1418 phdr = alloca (maplength);
1419 __lseek (fd, ehdr->e_phoff, SEEK_SET);
1420 if (__libc_read (fd, (void *) phdr, maplength) != maplength)
1422 read_error:
1423 errval = errno;
1424 errstring = N_("cannot read file data");
1425 goto call_lose;
1429 /* Check .note.ABI-tag if present. */
1430 for (ph = phdr; ph < &phdr[ehdr->e_phnum]; ++ph)
1431 if (ph->p_type == PT_NOTE && ph->p_filesz == 32 && ph->p_align >= 4)
1433 if (ph->p_offset + 32 <= fbp->len)
1434 abi_note = (void *) (fbp->buf + ph->p_offset);
1435 else
1437 __lseek (fd, ph->p_offset, SEEK_SET);
1438 if (__libc_read (fd, (void *) abi_note_buf, 32) != 32)
1439 goto read_error;
1441 abi_note = abi_note_buf;
1444 if (memcmp (abi_note, &expected_note, sizeof (expected_note)))
1445 continue;
1447 osversion = (abi_note[5] & 0xff) * 65536
1448 + (abi_note[6] & 0xff) * 256
1449 + (abi_note[7] & 0xff);
1450 if (abi_note[4] != __ABI_TAG_OS
1451 || (GL(dl_osversion) && GL(dl_osversion) < osversion))
1453 close_and_out:
1454 __close (fd);
1455 __set_errno (ENOENT);
1456 fd = -1;
1459 break;
1463 return fd;
1466 /* Try to open NAME in one of the directories in *DIRSP.
1467 Return the fd, or -1. If successful, fill in *REALNAME
1468 with the malloc'd full directory name. If it turns out
1469 that none of the directories in *DIRSP exists, *DIRSP is
1470 replaced with (void *) -1, and the old value is free()d
1471 if MAY_FREE_DIRS is true. */
1473 static int
1474 open_path (const char *name, size_t namelen, int preloaded,
1475 struct r_search_path_struct *sps, char **realname,
1476 struct filebuf *fbp)
1478 struct r_search_path_elem **dirs = sps->dirs;
1479 char *buf;
1480 int fd = -1;
1481 const char *current_what = NULL;
1482 int any = 0;
1484 buf = alloca (max_dirnamelen + max_capstrlen + namelen);
1487 struct r_search_path_elem *this_dir = *dirs;
1488 size_t buflen = 0;
1489 size_t cnt;
1490 char *edp;
1491 int here_any = 0;
1492 int err;
1494 /* If we are debugging the search for libraries print the path
1495 now if it hasn't happened now. */
1496 if (__builtin_expect (GL(dl_debug_mask) & DL_DEBUG_LIBS, 0)
1497 && current_what != this_dir->what)
1499 current_what = this_dir->what;
1500 print_search_path (dirs, current_what, this_dir->where);
1503 edp = (char *) __mempcpy (buf, this_dir->dirname, this_dir->dirnamelen);
1504 for (cnt = 0; fd == -1 && cnt < ncapstr; ++cnt)
1506 /* Skip this directory if we know it does not exist. */
1507 if (this_dir->status[cnt] == nonexisting)
1508 continue;
1510 buflen =
1511 ((char *) __mempcpy (__mempcpy (edp, capstr[cnt].str,
1512 capstr[cnt].len),
1513 name, namelen)
1514 - buf);
1516 /* Print name we try if this is wanted. */
1517 if (__builtin_expect (GL(dl_debug_mask) & DL_DEBUG_LIBS, 0))
1518 INTUSE(_dl_debug_printf) (" trying file=%s\n", buf);
1520 fd = open_verify (buf, fbp);
1521 if (this_dir->status[cnt] == unknown)
1523 if (fd != -1)
1524 this_dir->status[cnt] = existing;
1525 else
1527 /* We failed to open machine dependent library. Let's
1528 test whether there is any directory at all. */
1529 struct stat64 st;
1531 buf[buflen - namelen - 1] = '\0';
1533 if (__xstat64 (_STAT_VER, buf, &st) != 0
1534 || ! S_ISDIR (st.st_mode))
1535 /* The directory does not exist or it is no directory. */
1536 this_dir->status[cnt] = nonexisting;
1537 else
1538 this_dir->status[cnt] = existing;
1542 /* Remember whether we found any existing directory. */
1543 here_any |= this_dir->status[cnt] == existing;
1545 if (fd != -1 && __builtin_expect (preloaded, 0)
1546 && INTUSE(__libc_enable_secure))
1548 /* This is an extra security effort to make sure nobody can
1549 preload broken shared objects which are in the trusted
1550 directories and so exploit the bugs. */
1551 struct stat64 st;
1553 if (__fxstat64 (_STAT_VER, fd, &st) != 0
1554 || (st.st_mode & S_ISUID) == 0)
1556 /* The shared object cannot be tested for being SUID
1557 or this bit is not set. In this case we must not
1558 use this object. */
1559 __close (fd);
1560 fd = -1;
1561 /* We simply ignore the file, signal this by setting
1562 the error value which would have been set by `open'. */
1563 errno = ENOENT;
1568 if (fd != -1)
1570 *realname = (char *) malloc (buflen);
1571 if (*realname != NULL)
1573 memcpy (*realname, buf, buflen);
1574 return fd;
1576 else
1578 /* No memory for the name, we certainly won't be able
1579 to load and link it. */
1580 __close (fd);
1581 return -1;
1584 if (here_any && (err = errno) != ENOENT && err != EACCES)
1585 /* The file exists and is readable, but something went wrong. */
1586 return -1;
1588 /* Remember whether we found anything. */
1589 any |= here_any;
1591 while (*++dirs != NULL);
1593 /* Remove the whole path if none of the directories exists. */
1594 if (__builtin_expect (! any, 0))
1596 /* Paths which were allocated using the minimal malloc() in ld.so
1597 must not be freed using the general free() in libc. */
1598 if (sps->malloced)
1599 free (sps->dirs);
1600 sps->dirs = (void *) -1;
1603 return -1;
1606 /* Map in the shared object file NAME. */
1608 struct link_map *
1609 internal_function
1610 _dl_map_object (struct link_map *loader, const char *name, int preloaded,
1611 int type, int trace_mode, int mode)
1613 int fd;
1614 char *realname;
1615 char *name_copy;
1616 struct link_map *l;
1617 struct filebuf fb;
1619 /* Look for this name among those already loaded. */
1620 for (l = GL(dl_loaded); l; l = l->l_next)
1622 /* If the requested name matches the soname of a loaded object,
1623 use that object. Elide this check for names that have not
1624 yet been opened. */
1625 if (__builtin_expect (l->l_faked, 0) != 0)
1626 continue;
1627 if (!_dl_name_match_p (name, l))
1629 const char *soname;
1631 if (__builtin_expect (l->l_soname_added, 1)
1632 || l->l_info[DT_SONAME] == NULL)
1633 continue;
1635 soname = ((const char *) D_PTR (l, l_info[DT_STRTAB])
1636 + l->l_info[DT_SONAME]->d_un.d_val);
1637 if (strcmp (name, soname) != 0)
1638 continue;
1640 /* We have a match on a new name -- cache it. */
1641 add_name_to_object (l, soname);
1642 l->l_soname_added = 1;
1645 /* We have a match. */
1646 return l;
1649 /* Display information if we are debugging. */
1650 if (__builtin_expect (GL(dl_debug_mask) & DL_DEBUG_FILES, 0)
1651 && loader != NULL)
1652 INTUSE(_dl_debug_printf) ("\nfile=%s; needed by %s\n", name,
1653 loader->l_name[0]
1654 ? loader->l_name : rtld_progname);
1656 if (strchr (name, '/') == NULL)
1658 /* Search for NAME in several places. */
1660 size_t namelen = strlen (name) + 1;
1662 if (__builtin_expect (GL(dl_debug_mask) & DL_DEBUG_LIBS, 0))
1663 INTUSE(_dl_debug_printf) ("find library=%s; searching\n", name);
1665 fd = -1;
1667 /* When the object has the RUNPATH information we don't use any
1668 RPATHs. */
1669 if (loader == NULL || loader->l_info[DT_RUNPATH] == NULL)
1671 /* First try the DT_RPATH of the dependent object that caused NAME
1672 to be loaded. Then that object's dependent, and on up. */
1673 for (l = loader; fd == -1 && l; l = l->l_loader)
1675 if (l->l_rpath_dirs.dirs == NULL)
1677 if (l->l_info[DT_RPATH] == NULL)
1679 /* There is no path. */
1680 l->l_rpath_dirs.dirs = (void *) -1;
1681 continue;
1683 else
1685 /* Make sure the cache information is available. */
1686 size_t ptrval = (D_PTR (l, l_info[DT_STRTAB])
1687 + l->l_info[DT_RPATH]->d_un.d_val);
1688 decompose_rpath (&l->l_rpath_dirs,
1689 (const char *) ptrval, l, "RPATH");
1693 if (l->l_rpath_dirs.dirs != (void *) -1)
1694 fd = open_path (name, namelen, preloaded, &l->l_rpath_dirs,
1695 &realname, &fb);
1698 /* If dynamically linked, try the DT_RPATH of the executable
1699 itself. */
1700 l = GL(dl_loaded);
1701 if (fd == -1 && l && l->l_type != lt_loaded && l != loader
1702 && l->l_rpath_dirs.dirs != (void *) -1)
1703 fd = open_path (name, namelen, preloaded, &l->l_rpath_dirs,
1704 &realname, &fb);
1707 /* Try the LD_LIBRARY_PATH environment variable. */
1708 if (fd == -1 && env_path_list.dirs != (void *) -1)
1709 fd = open_path (name, namelen, preloaded, &env_path_list,
1710 &realname, &fb);
1712 /* Look at the RUNPATH information for this binary.
1714 Note that this is no real loop. 'while' is used only to enable
1715 us to use 'break' instead of a 'goto' to jump to the end. The
1716 loop is always left after the first round. */
1717 while (fd == -1 && loader != NULL
1718 && loader->l_runpath_dirs.dirs != (void *) -1)
1720 if (loader->l_runpath_dirs.dirs == NULL)
1722 if (loader->l_info[DT_RUNPATH] == NULL)
1724 /* No RUNPATH. */
1725 loader->l_runpath_dirs.dirs = (void *) -1;
1726 break;
1728 else
1730 /* Make sure the cache information is available. */
1731 size_t ptrval = (D_PTR (loader, l_info[DT_STRTAB])
1732 + loader->l_info[DT_RUNPATH]->d_un.d_val);
1733 decompose_rpath (&loader->l_runpath_dirs,
1734 (const char *) ptrval, loader, "RUNPATH");
1738 if (loader->l_runpath_dirs.dirs != (void *) -1)
1739 fd = open_path (name, namelen, preloaded,
1740 &loader->l_runpath_dirs, &realname, &fb);
1741 break;
1744 if (fd == -1
1745 && (__builtin_expect (! preloaded, 1)
1746 || ! INTUSE(__libc_enable_secure)))
1748 /* Check the list of libraries in the file /etc/ld.so.cache,
1749 for compatibility with Linux's ldconfig program. */
1750 const char *cached = _dl_load_cache_lookup (name);
1752 if (cached != NULL)
1754 #ifdef SHARED
1755 l = loader ?: GL(dl_loaded);
1756 #else
1757 l = loader;
1758 #endif
1760 /* If the loader has the DF_1_NODEFLIB flag set we must not
1761 use a cache entry from any of these directories. */
1762 if (
1763 #ifndef SHARED
1764 /* 'l' is always != NULL for dynamically linked objects. */
1765 l != NULL &&
1766 #endif
1767 __builtin_expect (l->l_flags_1 & DF_1_NODEFLIB, 0))
1769 const char *dirp = system_dirs;
1770 unsigned int cnt = 0;
1774 if (memcmp (cached, dirp, system_dirs_len[cnt]) == 0)
1776 /* The prefix matches. Don't use the entry. */
1777 cached = NULL;
1778 break;
1781 dirp += system_dirs_len[cnt] + 1;
1782 ++cnt;
1784 while (cnt < nsystem_dirs_len);
1787 if (cached != NULL)
1789 fd = open_verify (cached, &fb);
1790 if (__builtin_expect (fd != -1, 1))
1792 realname = local_strdup (cached);
1793 if (realname == NULL)
1795 __close (fd);
1796 fd = -1;
1803 /* Finally, try the default path. */
1804 if (fd == -1
1805 && ((l = loader ?: GL(dl_loaded)) == NULL
1806 || __builtin_expect (!(l->l_flags_1 & DF_1_NODEFLIB), 1))
1807 && rtld_search_dirs.dirs != (void *) -1)
1808 fd = open_path (name, namelen, preloaded, &rtld_search_dirs,
1809 &realname, &fb);
1811 /* Add another newline when we a tracing the library loading. */
1812 if (__builtin_expect (GL(dl_debug_mask) & DL_DEBUG_LIBS, 0))
1813 INTUSE(_dl_debug_printf) ("\n");
1815 else
1817 /* The path may contain dynamic string tokens. */
1818 realname = (loader
1819 ? expand_dynamic_string_token (loader, name)
1820 : local_strdup (name));
1821 if (realname == NULL)
1822 fd = -1;
1823 else
1825 fd = open_verify (realname, &fb);
1826 if (__builtin_expect (fd, 0) == -1)
1827 free (realname);
1831 if (__builtin_expect (fd, 0) == -1)
1833 if (trace_mode
1834 && __builtin_expect (GL(dl_debug_mask) & DL_DEBUG_PRELINK, 0) == 0)
1836 /* We haven't found an appropriate library. But since we
1837 are only interested in the list of libraries this isn't
1838 so severe. Fake an entry with all the information we
1839 have. */
1840 static const Elf_Symndx dummy_bucket = STN_UNDEF;
1842 /* Enter the new object in the list of loaded objects. */
1843 if ((name_copy = local_strdup (name)) == NULL
1844 || (l = _dl_new_object (name_copy, name, type, loader)) == NULL)
1845 INTUSE(_dl_signal_error) (ENOMEM, name, NULL, N_("\
1846 cannot create shared object descriptor"));
1847 /* Signal that this is a faked entry. */
1848 l->l_faked = 1;
1849 /* Since the descriptor is initialized with zero we do not
1850 have do this here.
1851 l->l_reserved = 0; */
1852 l->l_buckets = &dummy_bucket;
1853 l->l_nbuckets = 1;
1854 l->l_relocated = 1;
1856 return l;
1858 else
1859 INTUSE(_dl_signal_error) (errno, name, NULL,
1860 N_("cannot open shared object file"));
1863 return _dl_map_object_from_fd (name, fd, &fb, realname, loader, type, mode);
1865 INTDEF (_dl_map_object)