1 /* Map in a shared object's segments from the file.
2 Copyright (C) 1995,96,97,98,99,2000 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 Library General Public License as
7 published by the Free Software Foundation; either version 2 of the
8 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 Library General Public License for more details.
15 You should have received a copy of the GNU Library General Public
16 License along with the GNU C Library; see the file COPYING.LIB. If not,
17 write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA. */
29 #include <sys/param.h>
31 #include <sys/types.h>
32 #include "dynamic-link.h"
33 #include <stdio-common/_itoa.h>
37 /* On some systems, no flag bits are given to specify file mapping. */
42 /* The right way to map in the shared library files is MAP_COPY, which
43 makes a virtual copy of the data at the time of the mmap call; this
44 guarantees the mapped pages will be consistent even if the file is
45 overwritten. Some losing VM systems like Linux's lack MAP_COPY. All we
46 get is MAP_PRIVATE, which copies each page when it is modified; this
47 means if the file is overwritten, we may at some point get some pages
48 from the new version after starting with pages from the old version. */
50 # define MAP_COPY MAP_PRIVATE
53 /* Some systems link their relocatable objects for another base address
54 than 0. We want to know the base address for these such that we can
55 subtract this address from the segment addresses during mapping.
56 This results in a more efficient address space usage. Defaults to
57 zero for almost all systems. */
59 # define MAP_BASE_ADDR(l) 0
64 #if BYTE_ORDER == BIG_ENDIAN
65 # define byteorder ELFDATA2MSB
66 #elif BYTE_ORDER == LITTLE_ENDIAN
67 # define byteorder ELFDATA2LSB
69 # error "Unknown BYTE_ORDER " BYTE_ORDER
70 # define byteorder ELFDATANONE
73 #define STRING(x) __STRING (x)
76 /* The fd is not examined when using MAP_ANON. */
80 # define ANONFD _dl_zerofd
83 /* Handle situations where we have a preferred location in memory for
84 the shared objects. */
85 #ifdef ELF_PREFERRED_ADDRESS_DATA
86 ELF_PREFERRED_ADDRESS_DATA;
88 #ifndef ELF_PREFERRED_ADDRESS
89 # define ELF_PREFERRED_ADDRESS(loader, maplength, mapstartpref) (mapstartpref)
91 #ifndef ELF_FIXED_ADDRESS
92 # define ELF_FIXED_ADDRESS(loader, mapstart) ((void) 0)
95 /* Type for the buffer we put the ELF header and hopefully the program
96 header. This buffer does not really have to be too large. In most
97 cases the program header follows the ELF header directly. If this
98 is not the case all bets are off and we can make the header arbitrarily
99 large and still won't get it read. This means the only question is
100 how large are the ELF and program header combined. The ELF header
101 in 64-bit files is 56 bytes long. Each program header entry is again
102 56 bytes long. I.e., even with a file which has 17 program header
103 entries we only have to read 1kB. And 17 program header entries is
104 plenty, normal files have < 10. If this heuristic should really fail
105 for some file the code in `_dl_map_object_from_fd' knows how to
115 extern const char *_dl_platform;
116 extern size_t _dl_platformlen;
118 /* This is the decomposed LD_LIBRARY_PATH search path. */
119 static struct r_search_path_struct env_path_list;
121 /* List of the hardware capabilities we might end up using. */
122 static const struct r_strlenpair *capstr;
123 static size_t ncapstr;
124 static size_t max_capstrlen;
126 const unsigned char _dl_pf_to_prot[8] =
131 [PF_R | PF_W] = PROT_READ | PROT_WRITE,
133 [PF_R | PF_X] = PROT_READ | PROT_EXEC,
134 [PF_W | PF_X] = PROT_WRITE | PROT_EXEC,
135 [PF_R | PF_W | PF_X] = PROT_READ | PROT_WRITE | PROT_EXEC
139 /* Get the generated information about the trusted directories. */
140 #include "trusted-dirs.h"
142 static const char system_dirs[] = SYSTEM_DIRS;
143 static const size_t system_dirs_len[] =
147 #define nsystem_dirs_len \
148 (sizeof (system_dirs_len) / sizeof (system_dirs_len[0]))
151 /* Local version of `strdup' function. */
153 local_strdup (const char *s)
155 size_t len = strlen (s) + 1;
156 void *new = malloc (len);
161 return (char *) memcpy (new, s, len);
166 _dl_dst_count (const char *name, int is_path)
168 const char *const start = name;
175 /* $ORIGIN is not expanded for SUID/GUID programs.
177 Note that it is no bug that the strings in the first two `strncmp'
178 calls are longer than the sequence which is actually tested. */
179 if ((((strncmp (&name[1], "ORIGIN}", 6) == 0
180 && (!__libc_enable_secure
181 || ((name[7] == '\0' || (is_path && name[7] == ':'))
182 && (name == start || (is_path && name[-1] == ':'))))
184 || (strncmp (&name[1], "PLATFORM}", 8) == 0 && (len = 9) != 0))
185 && (name[len] == '\0' || name[len] == '/'
186 || (is_path && name[len] == ':')))
188 && ((strncmp (&name[2], "ORIGIN}", 7) == 0
189 && (!__libc_enable_secure
190 || ((name[9] == '\0' || (is_path && name[9] == ':'))
191 && (name == start || (is_path && name[-1] == ':'))))
193 || (strncmp (&name[2], "PLATFORM}", 9) == 0
194 && (len = 11) != 0))))
197 name = strchr (name + len, '$');
199 while (name != NULL);
206 _dl_dst_substitute (struct link_map *l, const char *name, char *result,
209 const char *const start = name;
210 char *last_elem, *wp;
212 /* Now fill the result path. While copying over the string we keep
213 track of the start of the last path element. When we come accross
214 a DST we copy over the value or (if the value is not available)
215 leave the entire path element out. */
216 last_elem = wp = result;
225 /* Note that it is no bug that the strings in the first two `strncmp'
226 calls are longer than the sequence which is actually tested. */
227 if ((((strncmp (&name[1], "ORIGIN}", 6) == 0 && (len = 7) != 0)
228 || (strncmp (&name[1], "PLATFORM}", 8) == 0 && (len = 9) != 0))
229 && (name[len] == '\0' || name[len] == '/'
230 || (is_path && name[len] == ':')))
232 && ((strncmp (&name[2], "ORIGIN}", 7) == 0 && (len = 9) != 0)
233 || (strncmp (&name[2], "PLATFORM}", 9) == 0
234 && (len = 11) != 0))))
236 repl = ((len == 7 || name[2] == 'O')
237 ? (__libc_enable_secure
238 && ((name[len] != '\0'
239 && (!is_path || name[len] != ':'))
241 && (!is_path || name[-1] != ':')))
242 ? NULL : l->l_origin)
245 if (repl != NULL && repl != (const char *) -1)
247 wp = __stpcpy (wp, repl);
252 /* We cannot use this path element, the value of the
253 replacement is unknown. */
256 while (*name != '\0' && (!is_path || *name != ':'))
261 /* No DST we recognize. */
264 else if (is_path && *name == ':')
272 while (*name != '\0');
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. */
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. */
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. */
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);
311 return 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. */
321 add_name_to_object (struct link_map *l, const char *name)
323 struct libname_list *lnp, *lastp;
324 struct libname_list *newname;
328 for (lnp = l->l_libname; lnp != NULL; lastp = lnp, lnp = lnp->next)
329 if (strcmp (name, lnp->name) == 0)
332 name_len = strlen (name) + 1;
333 newname = (struct libname_list *) malloc (sizeof *newname + name_len);
336 /* No more memory. */
337 _dl_signal_error (ENOMEM, name, N_("cannot allocate name record"));
340 /* The object should have a libname set from _dl_new_object. */
341 assert (lastp != NULL);
343 newname->name = memcpy (newname + 1, name, name_len);
344 newname->next = NULL;
345 newname->dont_free = 0;
346 lastp->next = newname;
349 /* All known directories in sorted order. */
350 struct r_search_path_elem *_dl_all_dirs;
352 /* All directories after startup. */
353 struct r_search_path_elem *_dl_init_all_dirs;
355 /* Standard search directories. */
356 static struct r_search_path_struct rtld_search_dirs;
358 static size_t max_dirnamelen;
360 static inline struct r_search_path_elem **
361 fillin_rpath (char *rpath, struct r_search_path_elem **result, const char *sep,
362 int check_trusted, const char *what, const char *where)
367 while ((cp = __strsep (&rpath, sep)) != NULL)
369 struct r_search_path_elem *dirp;
370 size_t len = strlen (cp);
372 /* `strsep' can pass an empty string. This has to be
373 interpreted as `use the current directory'. */
376 static const char curwd[] = "./";
380 /* Remove trailing slashes (except for "/"). */
381 while (len > 1 && cp[len - 1] == '/')
384 /* Now add one if there is none so far. */
385 if (len > 0 && cp[len - 1] != '/')
388 /* See if this directory is already known. */
389 for (dirp = _dl_all_dirs; dirp != NULL; dirp = dirp->next)
390 if (dirp->dirnamelen == len && memcmp (cp, dirp->dirname, len) == 0)
395 /* It is available, see whether it's on our own list. */
397 for (cnt = 0; cnt < nelems; ++cnt)
398 if (result[cnt] == dirp)
402 result[nelems++] = dirp;
407 enum r_dir_status init_val;
408 size_t where_len = where ? strlen (where) + 1 : 0;
410 /* It's a new directory. Create an entry and add it. */
411 dirp = (struct r_search_path_elem *)
412 malloc (sizeof (*dirp) + ncapstr * sizeof (enum r_dir_status)
413 + where_len + len + 1);
415 _dl_signal_error (ENOMEM, NULL,
416 N_("cannot create cache for search path"));
418 dirp->dirname = ((char *) dirp + sizeof (*dirp)
419 + ncapstr * sizeof (enum r_dir_status));
420 memcpy ((char *) dirp->dirname, cp, len + 1);
421 dirp->dirnamelen = len;
423 if (len > max_dirnamelen)
424 max_dirnamelen = len;
426 /* Make sure we don't use untrusted directories if we run SUID. */
427 if (__builtin_expect (check_trusted, 0))
429 const char *trun = system_dirs;
432 /* By default we don't trust anything. */
433 init_val = nonexisting;
435 /* All trusted directories must be complete names. */
438 for (idx = 0; idx < nsystem_dirs_len; ++idx)
440 if (len == system_dirs_len[idx]
441 && memcmp (trun, cp, len) == 0)
445 trun += system_dirs_len[idx] + 1;
448 if (idx < nsystem_dirs_len)
449 /* It's a trusted directory so allow checking for it. */
454 /* We don't have to check for trusted directories and can
455 accept everything. We have to make sure all the
456 relative directories are never ignored. The current
457 directory might change and all our saved information
459 init_val = cp[0] != '/' ? existing : unknown;
461 for (cnt = 0; cnt < ncapstr; ++cnt)
462 dirp->status[cnt] = init_val;
465 if (__builtin_expect (where != NULL, 1))
466 dirp->where = memcpy ((char *) dirp + sizeof (*dirp) + len + 1
467 + ncapstr * sizeof (enum r_dir_status),
472 dirp->next = _dl_all_dirs;
475 /* Put it in the result array. */
476 result[nelems++] = dirp;
480 /* Terminate the array. */
481 result[nelems] = NULL;
489 decompose_rpath (struct r_search_path_struct *sps,
490 const char *rpath, struct link_map *l, const char *what)
492 /* Make a copy we can work with. */
493 const char *where = l->l_name;
496 struct r_search_path_elem **result;
499 /* First see whether we must forget the RUNPATH and RPATH from this
501 if (__builtin_expect (_dl_inhibit_rpath != NULL, 0) && !__libc_enable_secure)
503 const char *found = strstr (_dl_inhibit_rpath, where);
506 size_t len = strlen (where);
507 if ((found == _dl_inhibit_rpath || found[-1] == ':')
508 && (found[len] == '\0' || found[len] == ':'))
510 /* This object is on the list of objects for which the
511 RUNPATH and RPATH must not be used. */
512 result = (struct r_search_path_elem **)
513 malloc (sizeof (*result));
515 _dl_signal_error (ENOMEM, NULL,
516 N_("cannot create cache for search path"));
527 /* Make a writable copy. At the same time expand possible dynamic
529 copy = expand_dynamic_string_token (l, rpath);
531 _dl_signal_error (ENOMEM, NULL, N_("cannot create RUNPATH/RPATH copy"));
533 /* Count the number of necessary elements in the result array. */
535 for (cp = copy; *cp != '\0'; ++cp)
539 /* Allocate room for the result. NELEMS + 1 is an upper limit for the
540 number of necessary entries. */
541 result = (struct r_search_path_elem **) malloc ((nelems + 1 + 1)
544 _dl_signal_error (ENOMEM, NULL, N_("cannot create cache for search path"));
546 fillin_rpath (copy, result, ":", 0, what, where);
548 /* Free the copied RPATH string. `fillin_rpath' make own copies if
553 /* The caller will change this value if we haven't used a real malloc. */
560 _dl_init_paths (const char *llp)
564 struct r_search_path_elem *pelem, **aelem;
570 /* Fill in the information about the application's RPATH and the
571 directories addressed by the LD_LIBRARY_PATH environment variable. */
573 /* Get the capabilities. */
574 capstr = _dl_important_hwcaps (_dl_platform, _dl_platformlen,
575 &ncapstr, &max_capstrlen);
577 /* First set up the rest of the default search directory entries. */
578 aelem = rtld_search_dirs.dirs = (struct r_search_path_elem **)
579 malloc ((nsystem_dirs_len + 1) * sizeof (struct r_search_path_elem *));
580 if (rtld_search_dirs.dirs == NULL)
581 _dl_signal_error (ENOMEM, NULL, N_("cannot create search path array"));
583 round_size = ((2 * sizeof (struct r_search_path_elem) - 1
584 + ncapstr * sizeof (enum r_dir_status))
585 / sizeof (struct r_search_path_elem));
587 rtld_search_dirs.dirs[0] = (struct r_search_path_elem *)
588 malloc ((sizeof (system_dirs) / sizeof (system_dirs[0]))
589 * round_size * sizeof (struct r_search_path_elem));
590 if (rtld_search_dirs.dirs[0] == NULL)
591 _dl_signal_error (ENOMEM, NULL, N_("cannot create cache for search path"));
593 rtld_search_dirs.malloced = 0;
594 pelem = _dl_all_dirs = rtld_search_dirs.dirs[0];
604 pelem->what = "system search path";
607 pelem->dirname = strp;
608 pelem->dirnamelen = system_dirs_len[idx];
609 strp += system_dirs_len[idx] + 1;
611 /* System paths must be absolute. */
612 assert (pelem->dirname[0] == '/');
613 for (cnt = 0; cnt < ncapstr; ++cnt)
614 pelem->status[cnt] = unknown;
616 pelem->next = (++idx == nsystem_dirs_len ? NULL : (pelem + round_size));
620 while (idx < nsystem_dirs_len);
622 max_dirnamelen = SYSTEM_DIRS_MAX_LEN;
626 /* This points to the map of the main object. */
630 assert (l->l_type != lt_loaded);
632 if (l->l_info[DT_RUNPATH])
634 /* Allocate room for the search path and fill in information
636 decompose_rpath (&l->l_runpath_dirs,
637 (const void *) (D_PTR (l, l_info[DT_STRTAB])
638 + l->l_info[DT_RUNPATH]->d_un.d_val),
641 /* The RPATH is ignored. */
642 l->l_rpath_dirs.dirs = (void *) -1;
646 l->l_runpath_dirs.dirs = (void *) -1;
648 if (l->l_info[DT_RPATH])
650 /* Allocate room for the search path and fill in information
652 decompose_rpath (&l->l_rpath_dirs,
653 (const void *) (D_PTR (l, l_info[DT_STRTAB])
654 + l->l_info[DT_RPATH]->d_un.d_val),
656 l->l_rpath_dirs.malloced = 0;
659 l->l_rpath_dirs.dirs = (void *) -1;
664 if (llp != NULL && *llp != '\0')
667 const char *cp = llp;
669 /* Decompose the LD_LIBRARY_PATH contents. First determine how many
674 if (*cp == ':' || *cp == ';')
679 env_path_list.dirs = (struct r_search_path_elem **)
680 malloc ((nllp + 1) * sizeof (struct r_search_path_elem *));
681 if (env_path_list.dirs == NULL)
682 _dl_signal_error (ENOMEM, NULL,
683 N_("cannot create cache for search path"));
685 (void) fillin_rpath (strdupa (llp), env_path_list.dirs, ":;",
686 __libc_enable_secure, "LD_LIBRARY_PATH", NULL);
688 if (env_path_list.dirs[0] == NULL)
690 free (env_path_list.dirs);
691 env_path_list.dirs = (void *) -1;
694 env_path_list.malloced = 0;
697 env_path_list.dirs = (void *) -1;
699 /* Remember the last search directory added at startup. */
700 _dl_init_all_dirs = _dl_all_dirs;
704 /* Think twice before changing anything in this function. It is placed
705 here and prepared using the `alloca' magic to prevent it from being
706 inlined. The function is only called in case of an error. But then
707 performance does not count. The function used to be "inlinable" and
708 the compiled did so all the time. This increased the code size for
709 absolutely no good reason. */
710 #define LOSE(code, s) lose (code, fd, name, realname, l, s)
712 __attribute__ ((noreturn))
713 lose (int code, int fd, const char *name, char *realname, struct link_map *l,
716 /* The use of `alloca' here looks ridiculous but it helps. The goal
717 is to avoid the function from being inlined. There is no official
718 way to do this so we use this trick. gcc never inlines functions
719 which use `alloca'. */
720 int *a = alloca (sizeof (int));
722 (void) __close (a[0]);
725 /* Remove the stillborn object from the list and free it. */
727 l->l_prev->l_next = l->l_next;
729 l->l_next->l_prev = l->l_prev;
734 _dl_signal_error (code, name, msg);
738 /* Map in the shared object NAME, actually located in REALNAME, and already
741 #ifndef EXTERNAL_MAP_FROM_FD
745 _dl_map_object_from_fd (const char *name, int fd, struct filebuf *fbp,
746 char *realname, struct link_map *loader, int l_type,
749 struct link_map *l = NULL;
751 inline caddr_t map_segment (ElfW(Addr) mapstart, size_t len,
752 int prot, int fixed, off_t offset)
754 caddr_t mapat = __mmap ((caddr_t) mapstart, len, prot,
755 fixed|MAP_COPY|MAP_FILE,
757 if (mapat == MAP_FAILED)
758 LOSE (errno, N_("failed to map segment from shared object"));
762 const ElfW(Ehdr) *header;
763 const ElfW(Phdr) *phdr;
764 const ElfW(Phdr) *ph;
769 /* Get file information. */
770 if (__fxstat64 (_STAT_VER, fd, &st) < 0)
771 LOSE (errno, N_("cannot stat shared object"));
773 /* Look again to see if the real name matched another already loaded. */
774 for (l = _dl_loaded; l; l = l->l_next)
775 if (l->l_ino == st.st_ino && l->l_dev == st.st_dev)
779 /* The object is already loaded.
780 Just bump its reference count and return it. */
783 /* If the name is not in the list of names for this object add
786 add_name_to_object (l, name);
788 if (l->l_initfini != NULL)
789 for (i = 1; l->l_initfini[i] != NULL; ++i)
790 ++l->l_initfini[i]->l_opencount;
795 if (mode & RTLD_NOLOAD)
796 /* We are not supposed to load the object unless it is already
797 loaded. So return now. */
800 /* Print debugging message. */
801 if (__builtin_expect (_dl_debug_files, 0))
802 _dl_debug_message (1, "file=", name, "; generating link map\n", NULL);
804 /* This is the ELF header. We read it in `open_verify'. */
805 header = (void *) fbp->buf;
809 if (_dl_zerofd == -1)
811 _dl_zerofd = _dl_sysdep_open_zero_fill ();
812 if (_dl_zerofd == -1)
815 _dl_signal_error (errno, NULL, N_("cannot open zero fill device"));
820 /* Enter the new object in the list of loaded objects. */
821 l = _dl_new_object (realname, name, l_type, loader);
822 if (__builtin_expect (! l, 0))
823 LOSE (ENOMEM, N_("cannot create shared object descriptor"));
826 /* Extract the remaining details we need from the ELF header
827 and then read in the program header table. */
828 l->l_entry = header->e_entry;
829 type = header->e_type;
830 l->l_phnum = header->e_phnum;
832 maplength = header->e_phnum * sizeof (ElfW(Phdr));
833 if (header->e_phoff + maplength <= fbp->len)
834 phdr = (void *) (fbp->buf + header->e_phoff);
837 phdr = alloca (maplength);
838 __lseek (fd, SEEK_SET, header->e_phoff);
839 if (__libc_read (fd, (void *) phdr, maplength) != maplength)
840 LOSE (errno, N_("cannot read file data"));
844 /* Scan the program header table, collecting its load commands. */
847 ElfW(Addr) mapstart, mapend, dataend, allocend;
850 } loadcmds[l->l_phnum], *c;
851 size_t nloadcmds = 0;
853 /* The struct is initialized to zero so this is not necessary:
857 for (ph = phdr; ph < &phdr[l->l_phnum]; ++ph)
860 /* These entries tell us where to find things once the file's
861 segments are mapped in. We record the addresses it says
862 verbatim, and later correct for the run-time load address. */
864 l->l_ld = (void *) ph->p_vaddr;
865 l->l_ldnum = ph->p_memsz / sizeof (ElfW(Dyn));
868 l->l_phdr = (void *) ph->p_vaddr;
872 /* A load command tells us to map in part of the file.
873 We record the load commands and process them all later. */
874 if (ph->p_align % _dl_pagesize != 0)
875 LOSE (0, N_("ELF load command alignment not page-aligned"));
876 if ((ph->p_vaddr - ph->p_offset) % ph->p_align)
878 N_("ELF load command address/offset not properly aligned"));
880 struct loadcmd *c = &loadcmds[nloadcmds++];
881 c->mapstart = ph->p_vaddr & ~(ph->p_align - 1);
882 c->mapend = ((ph->p_vaddr + ph->p_filesz + _dl_pagesize - 1)
883 & ~(_dl_pagesize - 1));
884 c->dataend = ph->p_vaddr + ph->p_filesz;
885 c->allocend = ph->p_vaddr + ph->p_memsz;
886 c->mapoff = ph->p_offset & ~(ph->p_align - 1);
888 /* Optimize a common case. */
889 if ((PF_R | PF_W | PF_X) == 7
890 && (PROT_READ | PROT_WRITE | PROT_EXEC) == 7)
891 c->prot = _dl_pf_to_prot[ph->p_flags & (PF_R | PF_W | PF_X)];
895 if (ph->p_flags & PF_R)
896 c->prot |= PROT_READ;
897 if (ph->p_flags & PF_W)
898 c->prot |= PROT_WRITE;
899 if (ph->p_flags & PF_X)
900 c->prot |= PROT_EXEC;
906 /* Now process the load commands and map segments into memory. */
909 /* Length of the sections to be loaded. */
910 maplength = loadcmds[nloadcmds - 1].allocend - c->mapstart;
912 if (type == ET_DYN || type == ET_REL)
914 /* This is a position-independent shared object. We can let the
915 kernel map it anywhere it likes, but we must have space for all
916 the segments in their specified positions relative to the first.
917 So we map the first segment without MAP_FIXED, but with its
918 extent increased to cover all the segments. Then we remove
919 access from excess portion, and there is known sufficient space
920 there to remap from the later segments.
922 As a refinement, sometimes we have an address that we would
923 prefer to map such objects at; but this is only a preference,
924 the OS can do whatever it likes. */
926 mappref = (ELF_PREFERRED_ADDRESS (loader, maplength, c->mapstart)
927 - MAP_BASE_ADDR (l));
929 /* Remember which part of the address space this object uses. */
930 l->l_map_start = (ElfW(Addr)) map_segment (mappref, maplength, c->prot,
932 l->l_map_end = l->l_map_start + maplength;
933 l->l_addr = l->l_map_start - c->mapstart;
935 /* Change protection on the excess portion to disallow all access;
936 the portions we do not remap later will be inaccessible as if
937 unallocated. Then jump into the normal segment-mapping loop to
938 handle the portion of the segment past the end of the file
940 __mprotect ((caddr_t) (l->l_addr + c->mapend),
941 loadcmds[nloadcmds - 1].allocend - c->mapend,
948 /* This object is loaded at a fixed address. This must never
949 happen for objects loaded with dlopen(). */
950 if (mode & __RTLD_DLOPEN)
952 LOSE (0, N_("cannot dynamically load executable"));
955 /* Notify ELF_PREFERRED_ADDRESS that we have to load this one
957 ELF_FIXED_ADDRESS (loader, c->mapstart);
960 /* Remember which part of the address space this object uses. */
961 l->l_map_start = c->mapstart + l->l_addr;
962 l->l_map_end = l->l_map_start + maplength;
964 while (c < &loadcmds[nloadcmds])
966 if (c->mapend > c->mapstart)
967 /* Map the segment contents from the file. */
968 map_segment (l->l_addr + c->mapstart, c->mapend - c->mapstart,
969 c->prot, MAP_FIXED, c->mapoff);
973 && c->mapoff <= header->e_phoff
974 && (c->mapend - c->mapstart + c->mapoff
975 >= header->e_phoff + header->e_phnum * sizeof (ElfW(Phdr))))
976 /* Found the program header in this segment. */
977 l->l_phdr = (void *) (c->mapstart + header->e_phoff - c->mapoff);
979 if (c->allocend > c->dataend)
981 /* Extra zero pages should appear at the end of this segment,
982 after the data mapped from the file. */
983 ElfW(Addr) zero, zeroend, zeropage;
985 zero = l->l_addr + c->dataend;
986 zeroend = l->l_addr + c->allocend;
987 zeropage = (zero + _dl_pagesize - 1) & ~(_dl_pagesize - 1);
989 if (zeroend < zeropage)
990 /* All the extra data is in the last page of the segment.
991 We can just zero it. */
996 /* Zero the final part of the last page of the segment. */
997 if ((c->prot & PROT_WRITE) == 0)
1000 if (__mprotect ((caddr_t) (zero & ~(_dl_pagesize - 1)),
1001 _dl_pagesize, c->prot|PROT_WRITE) < 0)
1002 LOSE (errno, N_("cannot change memory protections"));
1004 memset ((void *) zero, 0, zeropage - zero);
1005 if ((c->prot & PROT_WRITE) == 0)
1006 __mprotect ((caddr_t) (zero & ~(_dl_pagesize - 1)),
1007 _dl_pagesize, c->prot);
1010 if (zeroend > zeropage)
1012 /* Map the remaining zero pages in from the zero fill FD. */
1014 mapat = __mmap ((caddr_t) zeropage, zeroend - zeropage,
1015 c->prot, MAP_ANON|MAP_PRIVATE|MAP_FIXED,
1017 if (mapat == MAP_FAILED)
1018 LOSE (errno, N_("cannot map zero-fill pages"));
1025 if (l->l_phdr == NULL)
1027 /* The program header is not contained in any of the segmenst.
1028 We have to allocate memory ourself and copy it over from
1029 out temporary place. */
1030 ElfW(Phdr) *newp = (ElfW(Phdr) *) malloc (header->e_phnum
1031 * sizeof (ElfW(Phdr)));
1033 LOSE (ENOMEM, N_("cannot allocate memory for program header"));
1035 l->l_phdr = memcpy (newp, phdr,
1036 (header->e_phnum * sizeof (ElfW(Phdr))));
1037 l->l_phdr_allocated = 1;
1040 /* Adjust the PT_PHDR value by the runtime load address. */
1041 (ElfW(Addr)) l->l_phdr += l->l_addr;
1044 /* We are done mapping in the file. We no longer need the descriptor. */
1047 if (l->l_type == lt_library && type == ET_EXEC)
1048 l->l_type = lt_executable;
1053 LOSE (0, N_("object file has no dynamic section"));
1056 (ElfW(Addr)) l->l_ld += l->l_addr;
1058 l->l_entry += l->l_addr;
1060 if (__builtin_expect (_dl_debug_files, 0))
1062 const size_t nibbles = sizeof (void *) * 2;
1063 char buf1[nibbles + 1];
1064 char buf2[nibbles + 1];
1065 char buf3[nibbles + 1];
1067 buf1[nibbles] = '\0';
1068 buf2[nibbles] = '\0';
1069 buf3[nibbles] = '\0';
1071 memset (buf1, '0', nibbles);
1072 memset (buf2, '0', nibbles);
1073 memset (buf3, '0', nibbles);
1074 _itoa_word ((unsigned long int) l->l_ld, &buf1[nibbles], 16, 0);
1075 _itoa_word ((unsigned long int) l->l_addr, &buf2[nibbles], 16, 0);
1076 _itoa_word (maplength, &buf3[nibbles], 16, 0);
1078 _dl_debug_message (1, " dynamic: 0x", buf1, " base: 0x", buf2,
1079 " size: 0x", buf3, "\n", NULL);
1080 memset (buf1, '0', nibbles);
1081 memset (buf2, '0', nibbles);
1082 memset (buf3, ' ', nibbles);
1083 _itoa_word ((unsigned long int) l->l_entry, &buf1[nibbles], 16, 0);
1084 _itoa_word ((unsigned long int) l->l_phdr, &buf2[nibbles], 16, 0);
1085 _itoa_word (l->l_phnum, &buf3[nibbles], 10, 0);
1086 _dl_debug_message (1, " entry: 0x", buf1, " phdr: 0x", buf2,
1087 " phnum: ", buf3, "\n\n", NULL);
1090 elf_get_dynamic_info (l);
1092 /* Make sure we are dlopen()ing an object which has the DF_1_NOOPEN
1094 if (__builtin_expect (l->l_flags_1 & DF_1_NOOPEN, 0)
1095 && (mode & __RTLD_DLOPEN))
1097 /* Remove from the module list. */
1098 assert (l->l_next == NULL);
1100 if (l->l_prev == NULL)
1101 /* No other module loaded. */
1105 l->l_prev->l_next = NULL;
1108 /* We are not supposed to load this object. Free all resources. */
1109 __munmap ((void *) l->l_map_start, l->l_map_end - l->l_map_start);
1111 free (l->l_libname);
1113 if (l->l_phdr_allocated)
1114 free ((void *) l->l_phdr);
1118 _dl_signal_error (0, name, N_("shared object cannot be dlopen()ed"));
1121 if (l->l_info[DT_HASH])
1124 /* If this object has DT_SYMBOLIC set modify now its scope. We don't
1125 have to do this for the main map. */
1126 if (__builtin_expect (l->l_info[DT_SYMBOLIC] != NULL, 0)
1127 && &l->l_searchlist != l->l_scope[0])
1129 /* Create an appropriate searchlist. It contains only this map.
1131 XXX This is the definition of DT_SYMBOLIC in SysVr4. The old
1132 GNU ld.so implementation had a different interpretation which
1133 is more reasonable. We are prepared to add this possibility
1134 back as part of a GNU extension of the ELF format. */
1135 l->l_symbolic_searchlist.r_list =
1136 (struct link_map **) malloc (sizeof (struct link_map *));
1138 if (l->l_symbolic_searchlist.r_list == NULL)
1139 LOSE (ENOMEM, N_("cannot create searchlist"));
1141 l->l_symbolic_searchlist.r_list[0] = l;
1142 l->l_symbolic_searchlist.r_nlist = 1;
1143 l->l_symbolic_searchlist.r_duplist = l->l_symbolic_searchlist.r_list;
1144 l->l_symbolic_searchlist.r_nduplist = 1;
1146 /* Now move the existing entries one back. */
1147 memmove (&l->l_scope[1], &l->l_scope[0],
1148 sizeof (l->l_scope) - sizeof (l->l_scope[0]));
1150 /* Now add the new entry. */
1151 l->l_scope[0] = &l->l_symbolic_searchlist;
1154 /* Finally the file information. */
1155 l->l_dev = st.st_dev;
1156 l->l_ino = st.st_ino;
1161 /* Print search path. */
1163 print_search_path (struct r_search_path_elem **list,
1164 const char *what, const char *name)
1166 char buf[max_dirnamelen + max_capstrlen];
1169 _dl_debug_message (1, " search path=", NULL);
1171 while (*list != NULL && (*list)->what == what) /* Yes, ==. */
1173 char *endp = __mempcpy (buf, (*list)->dirname, (*list)->dirnamelen);
1176 for (cnt = 0; cnt < ncapstr; ++cnt)
1177 if ((*list)->status[cnt] != nonexisting)
1179 char *cp = __mempcpy (endp, capstr[cnt].str, capstr[cnt].len);
1180 if (cp == buf || (cp == buf + 1 && buf[0] == '/'))
1184 _dl_debug_message (0, first ? "" : ":", buf, NULL);
1192 _dl_debug_message (0, "\t\t(", what, " from file ",
1193 name[0] ? name : _dl_argv[0], ")\n", NULL);
1195 _dl_debug_message (0, "\t\t(", what, ")\n", NULL);
1198 /* Open a file and verify it is an ELF file for this architecture. We
1199 ignore only ELF files for other architectures. Non-ELF files and
1200 ELF files with different header information cause fatal errors since
1201 this could mean there is something wrong in the installation and the
1202 user might want to know about this. */
1204 open_verify (const char *name, struct filebuf *fbp)
1206 /* This is the expected ELF header. */
1207 #define ELF32_CLASS ELFCLASS32
1208 #define ELF64_CLASS ELFCLASS64
1209 #ifndef VALID_ELF_HEADER
1210 # define VALID_ELF_HEADER(hdr,exp,size) (memcmp (hdr, exp, size) == 0)
1211 # define VALID_ELF_OSABI(osabi) (osabi == ELFOSABI_SYSV)
1212 # define VALID_ELF_ABIVERSION(ver) (ver == 0)
1214 static const unsigned char expected[EI_PAD] =
1216 [EI_MAG0] = ELFMAG0,
1217 [EI_MAG1] = ELFMAG1,
1218 [EI_MAG2] = ELFMAG2,
1219 [EI_MAG3] = ELFMAG3,
1220 [EI_CLASS] = ELFW(CLASS),
1221 [EI_DATA] = byteorder,
1222 [EI_VERSION] = EV_CURRENT,
1223 [EI_OSABI] = ELFOSABI_SYSV,
1228 /* Open the file. We always open files read-only. */
1229 fd = __open (name, O_RDONLY);
1234 /* We successfully openened the file. Now verify it is a file
1237 fbp->len = __libc_read (fd, fbp->buf, sizeof (fbp->buf));
1239 /* This is where the ELF header is loaded. */
1240 assert (sizeof (fbp->buf) > sizeof (ElfW(Ehdr)));
1241 ehdr = (ElfW(Ehdr) *) fbp->buf;
1243 /* Now run the tests. */
1244 if (__builtin_expect (fbp->len < (ssize_t) sizeof (ElfW(Ehdr)), 0))
1245 lose (errno, fd, name, NULL, NULL,
1246 errno == 0 ? N_("file too short") : N_("cannot read file data"));
1248 /* See whether the ELF header is what we expect. */
1249 if (__builtin_expect (! VALID_ELF_HEADER (ehdr->e_ident, expected,
1252 /* Something is wrong. */
1253 if (*(Elf32_Word *) &ehdr->e_ident !=
1254 #if BYTE_ORDER == LITTLE_ENDIAN
1255 ((ELFMAG0 << (EI_MAG0 * 8)) |
1256 (ELFMAG1 << (EI_MAG1 * 8)) |
1257 (ELFMAG2 << (EI_MAG2 * 8)) |
1258 (ELFMAG3 << (EI_MAG3 * 8)))
1260 ((ELFMAG0 << (EI_MAG3 * 8)) |
1261 (ELFMAG1 << (EI_MAG2 * 8)) |
1262 (ELFMAG2 << (EI_MAG1 * 8)) |
1263 (ELFMAG3 << (EI_MAG0 * 8)))
1266 lose (0, fd, name, NULL, NULL, N_("invalid ELF header"));
1268 if (ehdr->e_ident[EI_CLASS] != ELFW(CLASS))
1269 /* This is not a fatal error. On architectures where
1270 32-bit and 64-bit binaries can be run this might
1274 if (ehdr->e_ident[EI_DATA] != byteorder)
1276 if (BYTE_ORDER == BIG_ENDIAN)
1277 lose (0, fd, name, NULL, NULL,
1278 "ELF file data encoding not big-endian");
1280 lose (0, fd, name, NULL, NULL,
1281 "ELF file data encoding not little-endian");
1283 if (ehdr->e_ident[EI_VERSION] != EV_CURRENT)
1284 lose (0, fd, name, NULL, NULL,
1285 N_("ELF file version ident does not match current one"));
1286 /* XXX We should be able so set system specific versions which are
1288 if (!VALID_ELF_OSABI (ehdr->e_ident[EI_OSABI]))
1289 lose (0, fd, name, NULL, NULL, N_("ELF file OS ABI invalid."));
1290 if (!VALID_ELF_ABIVERSION (ehdr->e_ident[EI_ABIVERSION]))
1291 lose (0, fd, name, NULL, NULL,
1292 N_("ELF file ABI version invalid."));
1293 lose (0, fd, name, NULL, NULL, N_("internal error"));
1296 if (__builtin_expect (ehdr->e_version, EV_CURRENT) != EV_CURRENT)
1297 lose (0, fd, name, NULL, NULL,
1298 N_("ELF file version does not match current one"));
1299 if (! __builtin_expect (elf_machine_matches_host (ehdr), 1))
1303 __set_errno (ENOENT);
1306 else if (__builtin_expect (ehdr->e_phentsize, sizeof (ElfW(Phdr)))
1307 != sizeof (ElfW(Phdr)))
1308 lose (0, fd, name, NULL, NULL,
1309 N_("ELF file's phentsize not the expected size"));
1315 /* Try to open NAME in one of the directories in *DIRSP.
1316 Return the fd, or -1. If successful, fill in *REALNAME
1317 with the malloc'd full directory name. If it turns out
1318 that none of the directories in *DIRSP exists, *DIRSP is
1319 replaced with (void *) -1, and the old value is free()d
1320 if MAY_FREE_DIRS is true. */
1323 open_path (const char *name, size_t namelen, int preloaded,
1324 struct r_search_path_struct *sps, char **realname,
1325 struct filebuf *fbp)
1327 struct r_search_path_elem **dirs = sps->dirs;
1330 const char *current_what = NULL;
1333 buf = alloca (max_dirnamelen + max_capstrlen + namelen);
1336 struct r_search_path_elem *this_dir = *dirs;
1341 /* If we are debugging the search for libraries print the path
1342 now if it hasn't happened now. */
1343 if (__builtin_expect (_dl_debug_libs, 0)
1344 && current_what != this_dir->what)
1346 current_what = this_dir->what;
1347 print_search_path (dirs, current_what, this_dir->where);
1350 edp = (char *) __mempcpy (buf, this_dir->dirname, this_dir->dirnamelen);
1351 for (cnt = 0; fd == -1 && cnt < ncapstr; ++cnt)
1353 /* Skip this directory if we know it does not exist. */
1354 if (this_dir->status[cnt] == nonexisting)
1358 ((char *) __mempcpy (__mempcpy (edp,
1359 capstr[cnt].str, capstr[cnt].len),
1363 /* Print name we try if this is wanted. */
1364 if (__builtin_expect (_dl_debug_libs, 0))
1365 _dl_debug_message (1, " trying file=", buf, "\n", NULL);
1367 fd = open_verify (buf, fbp);
1368 if (this_dir->status[cnt] == unknown)
1371 this_dir->status[cnt] = existing;
1374 /* We failed to open machine dependent library. Let's
1375 test whether there is any directory at all. */
1378 buf[buflen - namelen - 1] = '\0';
1380 if (__xstat64 (_STAT_VER, buf, &st) != 0
1381 || ! S_ISDIR (st.st_mode))
1382 /* The directory does not exist or it is no directory. */
1383 this_dir->status[cnt] = nonexisting;
1385 this_dir->status[cnt] = existing;
1389 /* Remember whether we found any existing directory. */
1390 any |= this_dir->status[cnt] == existing;
1392 if (fd != -1 && preloaded && __libc_enable_secure)
1394 /* This is an extra security effort to make sure nobody can
1395 preload broken shared objects which are in the trusted
1396 directories and so exploit the bugs. */
1399 if (__fxstat64 (_STAT_VER, fd, &st) != 0
1400 || (st.st_mode & S_ISUID) == 0)
1402 /* The shared object cannot be tested for being SUID
1403 or this bit is not set. In this case we must not
1407 /* We simply ignore the file, signal this by setting
1408 the error value which would have been set by `open'. */
1416 *realname = malloc (buflen);
1417 if (*realname != NULL)
1419 memcpy (*realname, buf, buflen);
1424 /* No memory for the name, we certainly won't be able
1425 to load and link it. */
1430 if (errno != ENOENT && errno != EACCES)
1431 /* The file exists and is readable, but something went wrong. */
1434 while (*++dirs != NULL);
1436 /* Remove the whole path if none of the directories exists. */
1439 /* Paths which were allocated using the minimal malloc() in ld.so
1440 must not be freed using the general free() in libc. */
1443 sps->dirs = (void *) -1;
1449 /* Map in the shared object file NAME. */
1453 _dl_map_object (struct link_map *loader, const char *name, int preloaded,
1454 int type, int trace_mode, int mode)
1462 /* Look for this name among those already loaded. */
1463 for (l = _dl_loaded; l; l = l->l_next)
1467 /* If the requested name matches the soname of a loaded object,
1468 use that object. Elide this check for names that have not
1470 if (l->l_opencount <= 0)
1472 if (!_dl_name_match_p (name, l))
1476 if (__builtin_expect (l->l_soname_added, 1)
1477 || l->l_info[DT_SONAME] == NULL)
1480 soname = ((const char *) D_PTR (l, l_info[DT_STRTAB])
1481 + l->l_info[DT_SONAME]->d_un.d_val);
1482 if (strcmp (name, soname) != 0)
1485 /* We have a match on a new name -- cache it. */
1486 add_name_to_object (l, soname);
1487 l->l_soname_added = 1;
1490 /* We have a match -- bump the reference count and return it. */
1491 if (l->l_initfini != NULL)
1492 for (i = 1; l->l_initfini[i] != NULL; ++i)
1493 ++l->l_initfini[i]->l_opencount;
1498 /* Display information if we are debugging. */
1499 if (__builtin_expect (_dl_debug_files, 0) && loader != NULL)
1500 _dl_debug_message (1, "\nfile=", name, "; needed by ",
1501 loader->l_name[0] ? loader->l_name : _dl_argv[0],
1504 if (strchr (name, '/') == NULL)
1506 /* Search for NAME in several places. */
1508 size_t namelen = strlen (name) + 1;
1510 if (__builtin_expect (_dl_debug_libs, 0))
1511 _dl_debug_message (1, "find library=", name, "; searching\n", NULL);
1515 /* When the object has the RUNPATH information we don't use any
1517 if (loader == NULL || loader->l_info[DT_RUNPATH] == NULL)
1519 /* First try the DT_RPATH of the dependent object that caused NAME
1520 to be loaded. Then that object's dependent, and on up. */
1521 for (l = loader; fd == -1 && l; l = l->l_loader)
1523 if (l->l_rpath_dirs.dirs == NULL)
1525 if (l->l_info[DT_RPATH] == NULL)
1526 /* There is no path. */
1527 l->l_rpath_dirs.dirs = (void *) -1;
1530 /* Make sure the cache information is available. */
1531 size_t ptrval = (D_PTR (l, l_info[DT_STRTAB])
1532 + l->l_info[DT_RPATH]->d_un.d_val);
1533 decompose_rpath (&l->l_rpath_dirs,
1534 (const char *) ptrval, l, "RPATH");
1536 if (l->l_rpath_dirs.dirs != (void *) -1)
1537 fd = open_path (name, namelen, preloaded,
1538 &l->l_rpath_dirs, &realname, &fb);
1541 else if (l->l_rpath_dirs.dirs != (void *) -1)
1542 fd = open_path (name, namelen, preloaded, &l->l_rpath_dirs,
1546 /* If dynamically linked, try the DT_RPATH of the executable
1549 if (fd == -1 && l && l->l_type != lt_loaded && l != loader
1550 && l->l_rpath_dirs.dirs != (void *) -1)
1551 fd = open_path (name, namelen, preloaded, &l->l_rpath_dirs,
1555 /* Try the LD_LIBRARY_PATH environment variable. */
1556 if (fd == -1 && env_path_list.dirs != (void *) -1)
1557 fd = open_path (name, namelen, preloaded, &env_path_list,
1560 /* Look at the RUNPATH informaiton for this binary. */
1561 if (loader != NULL && loader->l_runpath_dirs.dirs != (void *) -1)
1563 if (loader->l_runpath_dirs.dirs == NULL)
1565 if (loader->l_info[DT_RUNPATH] == NULL)
1567 loader->l_runpath_dirs.dirs = (void *) -1;
1570 /* Make sure the cache information is available. */
1571 size_t ptrval = (D_PTR (loader, l_info[DT_STRTAB])
1572 + loader->l_info[DT_RUNPATH]->d_un.d_val);
1573 decompose_rpath (&loader->l_runpath_dirs,
1574 (const char *) ptrval, loader, "RUNPATH");
1576 if (loader->l_runpath_dirs.dirs != (void *) -1)
1577 fd = open_path (name, namelen, preloaded,
1578 &loader->l_runpath_dirs, &realname, &fb);
1581 else if (loader->l_runpath_dirs.dirs != (void *) -1)
1582 fd = open_path (name, namelen, preloaded,
1583 &loader->l_runpath_dirs, &realname, &fb);
1588 /* Check the list of libraries in the file /etc/ld.so.cache,
1589 for compatibility with Linux's ldconfig program. */
1590 extern const char *_dl_load_cache_lookup (const char *name);
1591 const char *cached = _dl_load_cache_lookup (name);
1594 l = loader ?: _dl_loaded;
1601 /* If the loader has the DF_1_NODEFLIB flag set we must not
1602 use a cache entry from any of these directories. */
1603 if (l && __builtin_expect (l->l_flags_1 & DF_1_NODEFLIB, 0))
1605 const char *dirp = system_dirs;
1610 if (memcmp (cached, dirp, system_dirs_len[cnt]) == 0)
1612 /* The prefix matches. Don't use the entry. */
1617 dirp += system_dirs_len[cnt] + 1;
1620 while (cnt < nsystem_dirs_len);
1625 fd = open_verify (cached, &fb);
1628 realname = local_strdup (cached);
1629 if (realname == NULL)
1639 /* Finally, try the default path. */
1642 __builtin_expect (!(l->l_flags_1 & DF_1_NODEFLIB), 1))
1643 && rtld_search_dirs.dirs != (void *) -1)
1644 fd = open_path (name, namelen, preloaded, &rtld_search_dirs,
1647 /* Add another newline when we a tracing the library loading. */
1648 if (__builtin_expect (_dl_debug_libs, 0))
1649 _dl_debug_message (1, "\n", NULL);
1653 /* The path may contain dynamic string tokens. */
1655 ? expand_dynamic_string_token (loader, name)
1656 : local_strdup (name));
1657 if (realname == NULL)
1661 fd = open_verify (realname, &fb);
1671 /* We haven't found an appropriate library. But since we
1672 are only interested in the list of libraries this isn't
1673 so severe. Fake an entry with all the information we
1675 static const Elf_Symndx dummy_bucket = STN_UNDEF;
1677 /* Enter the new object in the list of loaded objects. */
1678 if ((name_copy = local_strdup (name)) == NULL
1679 || (l = _dl_new_object (name_copy, name, type, loader)) == NULL)
1680 _dl_signal_error (ENOMEM, name,
1681 N_("cannot create shared object descriptor"));
1682 /* Signal that this is a faked entry. */
1684 /* Since the descriptor is initialized with zero we do not
1686 l->l_reserved = 0; */
1687 l->l_buckets = &dummy_bucket;
1694 _dl_signal_error (errno, name, N_("cannot open shared object file"));
1697 return _dl_map_object_from_fd (name, fd, &fb, realname, loader, type, mode);