1 /* Map in a shared object's segments from the file.
2 Copyright (C) 1995-2002, 2003, 2004 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
29 #include <bits/wordsize.h>
31 #include <sys/param.h>
33 #include <sys/types.h>
34 #include "dynamic-link.h"
36 #include <dl-osinfo.h>
40 /* On some systems, no flag bits are given to specify file mapping. */
45 /* The right way to map in the shared library files is MAP_COPY, which
46 makes a virtual copy of the data at the time of the mmap call; this
47 guarantees the mapped pages will be consistent even if the file is
48 overwritten. Some losing VM systems like Linux's lack MAP_COPY. All we
49 get is MAP_PRIVATE, which copies each page when it is modified; this
50 means if the file is overwritten, we may at some point get some pages
51 from the new version after starting with pages from the old version. */
53 # define MAP_COPY MAP_PRIVATE
56 /* Some systems link their relocatable objects for another base address
57 than 0. We want to know the base address for these such that we can
58 subtract this address from the segment addresses during mapping.
59 This results in a more efficient address space usage. Defaults to
60 zero for almost all systems. */
62 # define MAP_BASE_ADDR(l) 0
67 #if BYTE_ORDER == BIG_ENDIAN
68 # define byteorder ELFDATA2MSB
69 #elif BYTE_ORDER == LITTLE_ENDIAN
70 # define byteorder ELFDATA2LSB
72 # error "Unknown BYTE_ORDER " BYTE_ORDER
73 # define byteorder ELFDATANONE
76 #define STRING(x) __STRING (x)
79 /* The fd is not examined when using MAP_ANON. */
83 # define ANONFD _dl_zerofd
86 /* Handle situations where we have a preferred location in memory for
87 the shared objects. */
88 #ifdef ELF_PREFERRED_ADDRESS_DATA
89 ELF_PREFERRED_ADDRESS_DATA
;
91 #ifndef ELF_PREFERRED_ADDRESS
92 # define ELF_PREFERRED_ADDRESS(loader, maplength, mapstartpref) (mapstartpref)
94 #ifndef ELF_FIXED_ADDRESS
95 # define ELF_FIXED_ADDRESS(loader, mapstart) ((void) 0)
98 /* Type for the buffer we put the ELF header and hopefully the program
99 header. This buffer does not really have to be too large. In most
100 cases the program header follows the ELF header directly. If this
101 is not the case all bets are off and we can make the header
102 arbitrarily large and still won't get it read. This means the only
103 question is how large are the ELF and program header combined. The
104 ELF header 32-bit files is 52 bytes long and in 64-bit files is 64
105 bytes long. Each program header entry is again 32 and 56 bytes
106 long respectively. I.e., even with a file which has 7 program
107 header entries we only have to read 512B. Add to this a bit of
108 margin for program notes and reading 512B and 640B for 32-bit and
109 64-bit files respecitvely is enough. If this heuristic should
110 really fail for some file the code in `_dl_map_object_from_fd'
111 knows how to recover. */
116 # define FILEBUF_SIZE 512
118 # define FILEBUF_SIZE 640
120 char buf
[FILEBUF_SIZE
] __attribute__ ((aligned (__alignof (ElfW(Ehdr
)))));
123 /* This is the decomposed LD_LIBRARY_PATH search path. */
124 static struct r_search_path_struct env_path_list attribute_relro
;
126 /* List of the hardware capabilities we might end up using. */
127 static const struct r_strlenpair
*capstr attribute_relro
;
128 static size_t ncapstr attribute_relro
;
129 static size_t max_capstrlen attribute_relro
;
132 /* Get the generated information about the trusted directories. */
133 #include "trusted-dirs.h"
135 static const char system_dirs
[] = SYSTEM_DIRS
;
136 static const size_t system_dirs_len
[] =
140 #define nsystem_dirs_len \
141 (sizeof (system_dirs_len) / sizeof (system_dirs_len[0]))
144 /* Local version of `strdup' function. */
146 local_strdup (const char *s
)
148 size_t len
= strlen (s
) + 1;
149 void *new = malloc (len
);
154 return (char *) memcpy (new, s
, len
);
159 is_dst (const char *start
, const char *name
, const char *str
,
160 int is_path
, int secure
)
163 bool is_curly
= false;
172 while (name
[len
] == str
[len
] && name
[len
] != '\0')
177 if (name
[len
] != '}')
180 /* Point again at the beginning of the name. */
182 /* Skip over closing curly brace and adjust for the --name. */
185 else if (name
[len
] != '\0' && name
[len
] != '/'
186 && (!is_path
|| name
[len
] != ':'))
189 if (__builtin_expect (secure
, 0)
190 && ((name
[len
] != '\0' && (!is_path
|| name
[len
] != ':'))
191 || (name
!= start
+ 1 && (!is_path
|| name
[-2] != ':'))))
199 _dl_dst_count (const char *name
, int is_path
)
201 const char *const start
= name
;
208 /* $ORIGIN is not expanded for SUID/GUID programs (except if it
209 is $ORIGIN alone) and it must always appear first in path. */
211 if ((len
= is_dst (start
, name
, "ORIGIN", is_path
,
212 INTUSE(__libc_enable_secure
))) != 0
213 || (len
= is_dst (start
, name
, "PLATFORM", is_path
, 0)) != 0
214 || (len
= is_dst (start
, name
, "LIB", is_path
, 0)) != 0)
217 name
= strchr (name
+ len
, '$');
219 while (name
!= NULL
);
223 INTDEF (_dl_dst_count
)
227 _dl_dst_substitute (struct link_map
*l
, const char *name
, char *result
,
230 const char *const start
= name
;
231 char *last_elem
, *wp
;
233 /* Now fill the result path. While copying over the string we keep
234 track of the start of the last path element. When we come accross
235 a DST we copy over the value or (if the value is not available)
236 leave the entire path element out. */
237 last_elem
= wp
= result
;
241 if (__builtin_expect (*name
== '$', 0))
243 const char *repl
= NULL
;
247 if ((len
= is_dst (start
, name
, "ORIGIN", is_path
,
248 INTUSE(__libc_enable_secure
))) != 0)
250 else if ((len
= is_dst (start
, name
, "PLATFORM", is_path
, 0)) != 0)
251 repl
= GL(dl_platform
);
252 else if ((len
= is_dst (start
, name
, "LIB", is_path
, 0)) != 0)
255 if (repl
!= NULL
&& repl
!= (const char *) -1)
257 wp
= __stpcpy (wp
, repl
);
262 /* We cannot use this path element, the value of the
263 replacement is unknown. */
266 while (*name
!= '\0' && (!is_path
|| *name
!= ':'))
270 /* No DST we recognize. */
276 if (is_path
&& *name
== ':')
280 while (*name
!= '\0');
286 INTDEF (_dl_dst_substitute
)
289 /* Return copy of argument with all recognized dynamic string tokens
290 ($ORIGIN and $PLATFORM for now) replaced. On some platforms it
291 might not be possible to determine the path from which the object
292 belonging to the map is loaded. In this case the path element
293 containing $ORIGIN is left out. */
295 expand_dynamic_string_token (struct link_map
*l
, const char *s
)
297 /* We make two runs over the string. First we determine how large the
298 resulting string is and then we copy it over. Since this is now
299 frequently executed operation we are looking here not for performance
300 but rather for code size. */
305 /* Determine the number of DST elements. */
306 cnt
= DL_DST_COUNT (s
, 1);
308 /* If we do not have to replace anything simply copy the string. */
309 if (__builtin_expect (cnt
, 0) == 0)
310 return local_strdup (s
);
312 /* Determine the length of the substituted string. */
313 total
= DL_DST_REQUIRED (l
, s
, strlen (s
), cnt
);
315 /* Allocate the necessary memory. */
316 result
= (char *) malloc (total
+ 1);
320 return INTUSE(_dl_dst_substitute
) (l
, s
, result
, 1);
324 /* Add `name' to the list of names for a particular shared object.
325 `name' is expected to have been allocated with malloc and will
326 be freed if the shared object already has this name.
327 Returns false if the object already had this name. */
330 add_name_to_object (struct link_map
*l
, const char *name
)
332 struct libname_list
*lnp
, *lastp
;
333 struct libname_list
*newname
;
337 for (lnp
= l
->l_libname
; lnp
!= NULL
; lastp
= lnp
, lnp
= lnp
->next
)
338 if (strcmp (name
, lnp
->name
) == 0)
341 name_len
= strlen (name
) + 1;
342 newname
= (struct libname_list
*) malloc (sizeof *newname
+ name_len
);
345 /* No more memory. */
346 INTUSE(_dl_signal_error
) (ENOMEM
, name
, NULL
,
347 N_("cannot allocate name record"));
350 /* The object should have a libname set from _dl_new_object. */
351 assert (lastp
!= NULL
);
353 newname
->name
= memcpy (newname
+ 1, name
, name_len
);
354 newname
->next
= NULL
;
355 newname
->dont_free
= 0;
356 lastp
->next
= newname
;
359 /* Standard search directories. */
360 static struct r_search_path_struct rtld_search_dirs attribute_relro
;
362 static size_t max_dirnamelen attribute_relro
;
364 static struct r_search_path_elem
**
365 fillin_rpath (char *rpath
, struct r_search_path_elem
**result
, const char *sep
,
366 int check_trusted
, const char *what
, const char *where
)
371 while ((cp
= __strsep (&rpath
, sep
)) != NULL
)
373 struct r_search_path_elem
*dirp
;
374 size_t len
= strlen (cp
);
376 /* `strsep' can pass an empty string. This has to be
377 interpreted as `use the current directory'. */
380 static const char curwd
[] = "./";
384 /* Remove trailing slashes (except for "/"). */
385 while (len
> 1 && cp
[len
- 1] == '/')
388 /* Now add one if there is none so far. */
389 if (len
> 0 && cp
[len
- 1] != '/')
392 /* Make sure we don't use untrusted directories if we run SUID. */
393 if (__builtin_expect (check_trusted
, 0))
395 const char *trun
= system_dirs
;
399 /* All trusted directories must be complete names. */
402 for (idx
= 0; idx
< nsystem_dirs_len
; ++idx
)
404 if (len
== system_dirs_len
[idx
]
405 && memcmp (trun
, cp
, len
) == 0)
412 trun
+= system_dirs_len
[idx
] + 1;
417 /* Simply drop this directory. */
421 /* See if this directory is already known. */
422 for (dirp
= GL(dl_all_dirs
); dirp
!= NULL
; dirp
= dirp
->next
)
423 if (dirp
->dirnamelen
== len
&& memcmp (cp
, dirp
->dirname
, len
) == 0)
428 /* It is available, see whether it's on our own list. */
430 for (cnt
= 0; cnt
< nelems
; ++cnt
)
431 if (result
[cnt
] == dirp
)
435 result
[nelems
++] = dirp
;
440 enum r_dir_status init_val
;
441 size_t where_len
= where
? strlen (where
) + 1 : 0;
443 /* It's a new directory. Create an entry and add it. */
444 dirp
= (struct r_search_path_elem
*)
445 malloc (sizeof (*dirp
) + ncapstr
* sizeof (enum r_dir_status
)
446 + where_len
+ len
+ 1);
448 INTUSE(_dl_signal_error
) (ENOMEM
, NULL
, NULL
,
449 N_("cannot create cache for search path"));
451 dirp
->dirname
= ((char *) dirp
+ sizeof (*dirp
)
452 + ncapstr
* sizeof (enum r_dir_status
));
453 *((char *) __mempcpy ((char *) dirp
->dirname
, cp
, len
)) = '\0';
454 dirp
->dirnamelen
= len
;
456 if (len
> max_dirnamelen
)
457 max_dirnamelen
= len
;
459 /* We have to make sure all the relative directories are
460 never ignored. The current directory might change and
461 all our saved information would be void. */
462 init_val
= cp
[0] != '/' ? existing
: unknown
;
463 for (cnt
= 0; cnt
< ncapstr
; ++cnt
)
464 dirp
->status
[cnt
] = init_val
;
467 if (__builtin_expect (where
!= NULL
, 1))
468 dirp
->where
= memcpy ((char *) dirp
+ sizeof (*dirp
) + len
+ 1
469 + (ncapstr
* sizeof (enum r_dir_status
)),
474 dirp
->next
= GL(dl_all_dirs
);
475 GL(dl_all_dirs
) = dirp
;
477 /* Put it in the result array. */
478 result
[nelems
++] = dirp
;
482 /* Terminate the array. */
483 result
[nelems
] = NULL
;
491 decompose_rpath (struct r_search_path_struct
*sps
,
492 const char *rpath
, struct link_map
*l
, const char *what
)
494 /* Make a copy we can work with. */
495 const char *where
= l
->l_name
;
498 struct r_search_path_elem
**result
;
500 /* Initialize to please the compiler. */
501 const char *errstring
= NULL
;
503 /* First see whether we must forget the RUNPATH and RPATH from this
505 if (__builtin_expect (GL(dl_inhibit_rpath
) != NULL
, 0)
506 && !INTUSE(__libc_enable_secure
))
508 const char *inhp
= GL(dl_inhibit_rpath
);
512 const char *wp
= where
;
514 while (*inhp
== *wp
&& *wp
!= '\0')
520 if (*wp
== '\0' && (*inhp
== '\0' || *inhp
== ':'))
522 /* This object is on the list of objects for which the
523 RUNPATH and RPATH must not be used. */
524 result
= calloc (1, sizeof *result
);
528 errstring
= N_("cannot create cache for search path");
530 INTUSE(_dl_signal_error
) (ENOMEM
, NULL
, NULL
, errstring
);
539 while (*inhp
!= '\0')
543 while (*inhp
!= '\0');
546 /* Make a writable copy. At the same time expand possible dynamic
548 copy
= expand_dynamic_string_token (l
, rpath
);
551 errstring
= N_("cannot create RUNPATH/RPATH copy");
555 /* Count the number of necessary elements in the result array. */
557 for (cp
= copy
; *cp
!= '\0'; ++cp
)
561 /* Allocate room for the result. NELEMS + 1 is an upper limit for the
562 number of necessary entries. */
563 result
= (struct r_search_path_elem
**) malloc ((nelems
+ 1 + 1)
566 goto signal_error_cache
;
568 fillin_rpath (copy
, result
, ":", 0, what
, where
);
570 /* Free the copied RPATH string. `fillin_rpath' make own copies if
575 /* The caller will change this value if we haven't used a real malloc. */
579 /* Make sure cached path information is stored in *SP
580 and return true if there are any paths to search there. */
582 cache_rpath (struct link_map
*l
,
583 struct r_search_path_struct
*sp
,
587 if (sp
->dirs
== (void *) -1)
590 if (sp
->dirs
!= NULL
)
593 if (l
->l_info
[tag
] == NULL
)
595 /* There is no path. */
596 sp
->dirs
= (void *) -1;
600 /* Make sure the cache information is available. */
601 decompose_rpath (sp
, (const char *) (D_PTR (l
, l_info
[DT_STRTAB
])
602 + l
->l_info
[tag
]->d_un
.d_val
),
610 _dl_init_paths (const char *llp
)
614 struct r_search_path_elem
*pelem
, **aelem
;
619 /* Initialize to please the compiler. */
620 const char *errstring
= NULL
;
622 /* Fill in the information about the application's RPATH and the
623 directories addressed by the LD_LIBRARY_PATH environment variable. */
625 /* Get the capabilities. */
626 capstr
= _dl_important_hwcaps (GL(dl_platform
), GL(dl_platformlen
),
627 &ncapstr
, &max_capstrlen
);
629 /* First set up the rest of the default search directory entries. */
630 aelem
= rtld_search_dirs
.dirs
= (struct r_search_path_elem
**)
631 malloc ((nsystem_dirs_len
+ 1) * sizeof (struct r_search_path_elem
*));
632 if (rtld_search_dirs
.dirs
== NULL
)
634 errstring
= N_("cannot create search path array");
636 INTUSE(_dl_signal_error
) (ENOMEM
, NULL
, NULL
, errstring
);
639 round_size
= ((2 * sizeof (struct r_search_path_elem
) - 1
640 + ncapstr
* sizeof (enum r_dir_status
))
641 / sizeof (struct r_search_path_elem
));
643 rtld_search_dirs
.dirs
[0] = (struct r_search_path_elem
*)
644 malloc ((sizeof (system_dirs
) / sizeof (system_dirs
[0]))
645 * round_size
* sizeof (struct r_search_path_elem
));
646 if (rtld_search_dirs
.dirs
[0] == NULL
)
648 errstring
= N_("cannot create cache for search path");
652 rtld_search_dirs
.malloced
= 0;
653 pelem
= GL(dl_all_dirs
) = rtld_search_dirs
.dirs
[0];
663 pelem
->what
= "system search path";
666 pelem
->dirname
= strp
;
667 pelem
->dirnamelen
= system_dirs_len
[idx
];
668 strp
+= system_dirs_len
[idx
] + 1;
670 /* System paths must be absolute. */
671 assert (pelem
->dirname
[0] == '/');
672 for (cnt
= 0; cnt
< ncapstr
; ++cnt
)
673 pelem
->status
[cnt
] = unknown
;
675 pelem
->next
= (++idx
== nsystem_dirs_len
? NULL
: (pelem
+ round_size
));
679 while (idx
< nsystem_dirs_len
);
681 max_dirnamelen
= SYSTEM_DIRS_MAX_LEN
;
685 /* This points to the map of the main object. */
689 assert (l
->l_type
!= lt_loaded
);
691 if (l
->l_info
[DT_RUNPATH
])
693 /* Allocate room for the search path and fill in information
695 decompose_rpath (&l
->l_runpath_dirs
,
696 (const void *) (D_PTR (l
, l_info
[DT_STRTAB
])
697 + l
->l_info
[DT_RUNPATH
]->d_un
.d_val
),
700 /* The RPATH is ignored. */
701 l
->l_rpath_dirs
.dirs
= (void *) -1;
705 l
->l_runpath_dirs
.dirs
= (void *) -1;
707 if (l
->l_info
[DT_RPATH
])
709 /* Allocate room for the search path and fill in information
711 decompose_rpath (&l
->l_rpath_dirs
,
712 (const void *) (D_PTR (l
, l_info
[DT_STRTAB
])
713 + l
->l_info
[DT_RPATH
]->d_un
.d_val
),
715 l
->l_rpath_dirs
.malloced
= 0;
718 l
->l_rpath_dirs
.dirs
= (void *) -1;
723 if (llp
!= NULL
&& *llp
!= '\0')
726 const char *cp
= llp
;
727 char *llp_tmp
= strdupa (llp
);
729 /* Decompose the LD_LIBRARY_PATH contents. First determine how many
734 if (*cp
== ':' || *cp
== ';')
739 env_path_list
.dirs
= (struct r_search_path_elem
**)
740 malloc ((nllp
+ 1) * sizeof (struct r_search_path_elem
*));
741 if (env_path_list
.dirs
== NULL
)
743 errstring
= N_("cannot create cache for search path");
747 (void) fillin_rpath (llp_tmp
, env_path_list
.dirs
, ":;",
748 INTUSE(__libc_enable_secure
), "LD_LIBRARY_PATH",
751 if (env_path_list
.dirs
[0] == NULL
)
753 free (env_path_list
.dirs
);
754 env_path_list
.dirs
= (void *) -1;
757 env_path_list
.malloced
= 0;
760 env_path_list
.dirs
= (void *) -1;
762 /* Remember the last search directory added at startup. */
763 GL(dl_init_all_dirs
) = GL(dl_all_dirs
);
767 /* Think twice before changing anything in this function. It is placed
768 here and prepared using the `alloca' magic to prevent it from being
769 inlined. The function is only called in case of an error. But then
770 performance does not count. The function used to be "inlinable" and
771 the compiled did so all the time. This increased the code size for
772 absolutely no good reason. */
774 __attribute__ ((noreturn
))
775 lose (int code
, int fd
, const char *name
, char *realname
, struct link_map
*l
,
778 /* The use of `alloca' here looks ridiculous but it helps. The goal
779 is to avoid the function from being inlined. There is no official
780 way to do this so we use this trick. gcc never inlines functions
781 which use `alloca'. */
782 int *a
= (int *) alloca (sizeof (int));
784 /* The file might already be closed. */
786 (void) __close (a
[0]);
789 /* Remove the stillborn object from the list and free it. */
790 assert (l
->l_next
== NULL
);
791 if (l
->l_prev
== NULL
)
792 /* No other module loaded. This happens only in the static library,
793 or in rtld under --verify. */
794 GL(dl_loaded
) = NULL
;
796 l
->l_prev
->l_next
= NULL
;
801 INTUSE(_dl_signal_error
) (code
, name
, NULL
, msg
);
805 /* Map in the shared object NAME, actually located in REALNAME, and already
808 #ifndef EXTERNAL_MAP_FROM_FD
812 _dl_map_object_from_fd (const char *name
, int fd
, struct filebuf
*fbp
,
813 char *realname
, struct link_map
*loader
, int l_type
,
814 int mode
, void **stack_endp
)
816 struct link_map
*l
= NULL
;
817 const ElfW(Ehdr
) *header
;
818 const ElfW(Phdr
) *phdr
;
819 const ElfW(Phdr
) *ph
;
823 /* Initialize to keep the compiler happy. */
824 const char *errstring
= NULL
;
827 /* Get file information. */
828 if (__builtin_expect (__fxstat64 (_STAT_VER
, fd
, &st
) < 0, 0))
830 errstring
= N_("cannot stat shared object");
834 lose (errval
, fd
, name
, realname
, l
, errstring
);
837 /* Look again to see if the real name matched another already loaded. */
838 for (l
= GL(dl_loaded
); l
; l
= l
->l_next
)
839 if (l
->l_ino
== st
.st_ino
&& l
->l_dev
== st
.st_dev
)
841 /* The object is already loaded.
842 Just bump its reference count and return it. */
845 /* If the name is not in the list of names for this object add
848 add_name_to_object (l
, name
);
853 if (mode
& RTLD_NOLOAD
)
854 /* We are not supposed to load the object unless it is already
855 loaded. So return now. */
858 /* Print debugging message. */
859 if (__builtin_expect (GL(dl_debug_mask
) & DL_DEBUG_FILES
, 0))
860 INTUSE(_dl_debug_printf
) ("file=%s; generating link map\n", name
);
862 /* This is the ELF header. We read it in `open_verify'. */
863 header
= (void *) fbp
->buf
;
867 if (_dl_zerofd
== -1)
869 _dl_zerofd
= _dl_sysdep_open_zero_fill ();
870 if (_dl_zerofd
== -1)
873 INTUSE(_dl_signal_error
) (errno
, NULL
, NULL
,
874 N_("cannot open zero fill device"));
879 /* Enter the new object in the list of loaded objects. */
880 l
= _dl_new_object (realname
, name
, l_type
, loader
);
881 if (__builtin_expect (! l
, 0))
883 errstring
= N_("cannot create shared object descriptor");
884 goto call_lose_errno
;
887 /* Extract the remaining details we need from the ELF header
888 and then read in the program header table. */
889 l
->l_entry
= header
->e_entry
;
890 type
= header
->e_type
;
891 l
->l_phnum
= header
->e_phnum
;
893 maplength
= header
->e_phnum
* sizeof (ElfW(Phdr
));
894 if (header
->e_phoff
+ maplength
<= (size_t) fbp
->len
)
895 phdr
= (void *) (fbp
->buf
+ header
->e_phoff
);
898 phdr
= alloca (maplength
);
899 __lseek (fd
, header
->e_phoff
, SEEK_SET
);
900 if ((size_t) __libc_read (fd
, (void *) phdr
, maplength
) != maplength
)
902 errstring
= N_("cannot read file data");
903 goto call_lose_errno
;
907 /* Presumed absent PT_GNU_STACK. */
908 uint_fast16_t stack_flags
= PF_R
|PF_W
|PF_X
;
911 /* Scan the program header table, collecting its load commands. */
914 ElfW(Addr
) mapstart
, mapend
, dataend
, allocend
;
917 } loadcmds
[l
->l_phnum
], *c
;
918 size_t nloadcmds
= 0;
919 bool has_holes
= false;
921 /* The struct is initialized to zero so this is not necessary:
925 for (ph
= phdr
; ph
< &phdr
[l
->l_phnum
]; ++ph
)
928 /* These entries tell us where to find things once the file's
929 segments are mapped in. We record the addresses it says
930 verbatim, and later correct for the run-time load address. */
932 l
->l_ld
= (void *) ph
->p_vaddr
;
933 l
->l_ldnum
= ph
->p_memsz
/ sizeof (ElfW(Dyn
));
937 l
->l_phdr
= (void *) ph
->p_vaddr
;
941 /* A load command tells us to map in part of the file.
942 We record the load commands and process them all later. */
943 if (__builtin_expect ((ph
->p_align
& (GL(dl_pagesize
) - 1)) != 0,
946 errstring
= N_("ELF load command alignment not page-aligned");
949 if (__builtin_expect (((ph
->p_vaddr
- ph
->p_offset
)
950 & (ph
->p_align
- 1)) != 0, 0))
953 = N_("ELF load command address/offset not properly aligned");
957 c
= &loadcmds
[nloadcmds
++];
958 c
->mapstart
= ph
->p_vaddr
& ~(ph
->p_align
- 1);
959 c
->mapend
= ((ph
->p_vaddr
+ ph
->p_filesz
+ GL(dl_pagesize
) - 1)
960 & ~(GL(dl_pagesize
) - 1));
961 c
->dataend
= ph
->p_vaddr
+ ph
->p_filesz
;
962 c
->allocend
= ph
->p_vaddr
+ ph
->p_memsz
;
963 c
->mapoff
= ph
->p_offset
& ~(ph
->p_align
- 1);
965 /* Determine whether there is a gap between the last segment
967 if (nloadcmds
> 1 && c
[-1].mapend
!= c
->mapstart
)
970 /* Optimize a common case. */
971 #if (PF_R | PF_W | PF_X) == 7 && (PROT_READ | PROT_WRITE | PROT_EXEC) == 7
972 c
->prot
= (PF_TO_PROT
973 >> ((ph
->p_flags
& (PF_R
| PF_W
| PF_X
)) * 4)) & 0xf;
976 if (ph
->p_flags
& PF_R
)
977 c
->prot
|= PROT_READ
;
978 if (ph
->p_flags
& PF_W
)
979 c
->prot
|= PROT_WRITE
;
980 if (ph
->p_flags
& PF_X
)
981 c
->prot
|= PROT_EXEC
;
987 if (ph
->p_memsz
== 0)
988 /* Nothing to do for an empty segment. */
991 l
->l_tls_blocksize
= ph
->p_memsz
;
992 l
->l_tls_align
= ph
->p_align
;
993 if (ph
->p_align
== 0)
994 l
->l_tls_firstbyte_offset
= 0;
996 l
->l_tls_firstbyte_offset
= ph
->p_vaddr
& (ph
->p_align
- 1);
997 l
->l_tls_initimage_size
= ph
->p_filesz
;
998 /* Since we don't know the load address yet only store the
999 offset. We will adjust it later. */
1000 l
->l_tls_initimage
= (void *) ph
->p_vaddr
;
1002 /* If not loading the initial set of shared libraries,
1003 check whether we should permit loading a TLS segment. */
1004 if (__builtin_expect (l
->l_type
== lt_library
, 1)
1005 /* If GL(dl_tls_dtv_slotinfo_list) == NULL, then rtld.c did
1006 not set up TLS data structures, so don't use them now. */
1007 || __builtin_expect (GL(dl_tls_dtv_slotinfo_list
) != NULL
, 1))
1009 /* Assign the next available module ID. */
1010 l
->l_tls_modid
= _dl_next_tls_modid ();
1015 if (l
->l_prev
== NULL
)
1016 /* We are loading the executable itself when the dynamic linker
1017 was executed directly. The setup will happen later. */
1020 /* In a static binary there is no way to tell if we dynamically
1021 loaded libpthread. */
1022 if (GL(dl_error_catch_tsd
) == &_dl_initial_error_catch_tsd
)
1025 /* We have not yet loaded libpthread.
1026 We can do the TLS setup right now! */
1030 /* The first call allocates TLS bookkeeping data structures.
1031 Then we allocate the TCB for the initial thread. */
1032 if (__builtin_expect (_dl_tls_setup (), 0)
1033 || __builtin_expect ((tcb
= _dl_allocate_tls (NULL
)) == NULL
,
1038 cannot allocate TLS data structures for initial thread");
1042 /* Now we install the TCB in the thread register. */
1043 errstring
= TLS_INIT_TP (tcb
, 0);
1044 if (__builtin_expect (errstring
== NULL
, 1))
1046 /* Now we are all good. */
1047 l
->l_tls_modid
= ++GL(dl_tls_max_dtv_idx
);
1051 /* The kernel is too old or somesuch. */
1053 _dl_deallocate_tls (tcb
, 1);
1058 /* Uh-oh, the binary expects TLS support but we cannot
1061 errstring
= N_("cannot handle TLS data");
1066 stack_flags
= ph
->p_flags
;
1070 l
->l_relro_addr
= ph
->p_vaddr
;
1071 l
->l_relro_size
= ph
->p_memsz
;
1075 if (__builtin_expect (nloadcmds
== 0, 0))
1077 /* This only happens for a bogus object that will be caught with
1078 another error below. But we don't want to go through the
1079 calculations below using NLOADCMDS - 1. */
1080 errstring
= N_("object file has no loadable segments");
1084 /* Now process the load commands and map segments into memory. */
1087 /* Length of the sections to be loaded. */
1088 maplength
= loadcmds
[nloadcmds
- 1].allocend
- c
->mapstart
;
1090 if (__builtin_expect (type
, ET_DYN
) == ET_DYN
)
1092 /* This is a position-independent shared object. We can let the
1093 kernel map it anywhere it likes, but we must have space for all
1094 the segments in their specified positions relative to the first.
1095 So we map the first segment without MAP_FIXED, but with its
1096 extent increased to cover all the segments. Then we remove
1097 access from excess portion, and there is known sufficient space
1098 there to remap from the later segments.
1100 As a refinement, sometimes we have an address that we would
1101 prefer to map such objects at; but this is only a preference,
1102 the OS can do whatever it likes. */
1104 mappref
= (ELF_PREFERRED_ADDRESS (loader
, maplength
,
1105 c
->mapstart
& GL(dl_use_load_bias
))
1106 - MAP_BASE_ADDR (l
));
1108 /* Remember which part of the address space this object uses. */
1109 l
->l_map_start
= (ElfW(Addr
)) __mmap ((void *) mappref
, maplength
,
1110 c
->prot
, MAP_COPY
| MAP_FILE
,
1112 if (__builtin_expect ((void *) l
->l_map_start
== MAP_FAILED
, 0))
1115 errstring
= N_("failed to map segment from shared object");
1116 goto call_lose_errno
;
1119 l
->l_map_end
= l
->l_map_start
+ maplength
;
1120 l
->l_addr
= l
->l_map_start
- c
->mapstart
;
1123 /* Change protection on the excess portion to disallow all access;
1124 the portions we do not remap later will be inaccessible as if
1125 unallocated. Then jump into the normal segment-mapping loop to
1126 handle the portion of the segment past the end of the file
1128 __mprotect ((caddr_t
) (l
->l_addr
+ c
->mapend
),
1129 loadcmds
[nloadcmds
- 1].allocend
- c
->mapend
,
1136 /* This object is loaded at a fixed address. This must never
1137 happen for objects loaded with dlopen(). */
1138 if (__builtin_expect ((mode
& __RTLD_OPENEXEC
) == 0, 0))
1140 errstring
= N_("cannot dynamically load executable");
1144 /* Notify ELF_PREFERRED_ADDRESS that we have to load this one
1146 ELF_FIXED_ADDRESS (loader
, c
->mapstart
);
1149 /* Remember which part of the address space this object uses. */
1150 l
->l_map_start
= c
->mapstart
+ l
->l_addr
;
1151 l
->l_map_end
= l
->l_map_start
+ maplength
;
1153 while (c
< &loadcmds
[nloadcmds
])
1155 if (c
->mapend
> c
->mapstart
1156 /* Map the segment contents from the file. */
1157 && (__mmap ((void *) (l
->l_addr
+ c
->mapstart
),
1158 c
->mapend
- c
->mapstart
, c
->prot
,
1159 MAP_FIXED
| MAP_COPY
| MAP_FILE
, fd
, c
->mapoff
)
1165 && (ElfW(Off
)) c
->mapoff
<= header
->e_phoff
1166 && ((size_t) (c
->mapend
- c
->mapstart
+ c
->mapoff
)
1167 >= header
->e_phoff
+ header
->e_phnum
* sizeof (ElfW(Phdr
))))
1168 /* Found the program header in this segment. */
1169 l
->l_phdr
= (void *) (c
->mapstart
+ header
->e_phoff
- c
->mapoff
);
1171 if (c
->allocend
> c
->dataend
)
1173 /* Extra zero pages should appear at the end of this segment,
1174 after the data mapped from the file. */
1175 ElfW(Addr
) zero
, zeroend
, zeropage
;
1177 zero
= l
->l_addr
+ c
->dataend
;
1178 zeroend
= l
->l_addr
+ c
->allocend
;
1179 zeropage
= ((zero
+ GL(dl_pagesize
) - 1)
1180 & ~(GL(dl_pagesize
) - 1));
1182 if (zeroend
< zeropage
)
1183 /* All the extra data is in the last page of the segment.
1184 We can just zero it. */
1187 if (zeropage
> zero
)
1189 /* Zero the final part of the last page of the segment. */
1190 if (__builtin_expect ((c
->prot
& PROT_WRITE
) == 0, 0))
1193 if (__mprotect ((caddr_t
) (zero
& ~(GL(dl_pagesize
) - 1)),
1194 GL(dl_pagesize
), c
->prot
|PROT_WRITE
) < 0)
1196 errstring
= N_("cannot change memory protections");
1197 goto call_lose_errno
;
1200 memset ((void *) zero
, '\0', zeropage
- zero
);
1201 if (__builtin_expect ((c
->prot
& PROT_WRITE
) == 0, 0))
1202 __mprotect ((caddr_t
) (zero
& ~(GL(dl_pagesize
) - 1)),
1203 GL(dl_pagesize
), c
->prot
);
1206 if (zeroend
> zeropage
)
1208 /* Map the remaining zero pages in from the zero fill FD. */
1210 mapat
= __mmap ((caddr_t
) zeropage
, zeroend
- zeropage
,
1211 c
->prot
, MAP_ANON
|MAP_PRIVATE
|MAP_FIXED
,
1213 if (__builtin_expect (mapat
== MAP_FAILED
, 0))
1215 errstring
= N_("cannot map zero-fill pages");
1216 goto call_lose_errno
;
1224 if (l
->l_phdr
== NULL
)
1226 /* The program header is not contained in any of the segments.
1227 We have to allocate memory ourself and copy it over from
1228 out temporary place. */
1229 ElfW(Phdr
) *newp
= (ElfW(Phdr
) *) malloc (header
->e_phnum
1230 * sizeof (ElfW(Phdr
)));
1233 errstring
= N_("cannot allocate memory for program header");
1234 goto call_lose_errno
;
1237 l
->l_phdr
= memcpy (newp
, phdr
,
1238 (header
->e_phnum
* sizeof (ElfW(Phdr
))));
1239 l
->l_phdr_allocated
= 1;
1242 /* Adjust the PT_PHDR value by the runtime load address. */
1243 (ElfW(Addr
)) l
->l_phdr
+= l
->l_addr
;
1247 /* Adjust the address of the TLS initialization image. */
1248 if (l
->l_tls_initimage
!= NULL
)
1249 l
->l_tls_initimage
= (char *) l
->l_tls_initimage
+ l
->l_addr
;
1252 /* We are done mapping in the file. We no longer need the descriptor. */
1254 /* Signal that we closed the file. */
1257 if (l
->l_type
== lt_library
&& type
== ET_EXEC
)
1258 l
->l_type
= lt_executable
;
1262 if (__builtin_expect (type
== ET_DYN
, 0))
1264 errstring
= N_("object file has no dynamic section");
1269 (ElfW(Addr
)) l
->l_ld
+= l
->l_addr
;
1271 l
->l_entry
+= l
->l_addr
;
1273 if (__builtin_expect (GL(dl_debug_mask
) & DL_DEBUG_FILES
, 0))
1274 INTUSE(_dl_debug_printf
) ("\
1275 dynamic: 0x%0*lx base: 0x%0*lx size: 0x%0*Zx\n\
1276 entry: 0x%0*lx phdr: 0x%0*lx phnum: %*u\n\n",
1277 (int) sizeof (void *) * 2,
1278 (unsigned long int) l
->l_ld
,
1279 (int) sizeof (void *) * 2,
1280 (unsigned long int) l
->l_addr
,
1281 (int) sizeof (void *) * 2, maplength
,
1282 (int) sizeof (void *) * 2,
1283 (unsigned long int) l
->l_entry
,
1284 (int) sizeof (void *) * 2,
1285 (unsigned long int) l
->l_phdr
,
1286 (int) sizeof (void *) * 2, l
->l_phnum
);
1288 elf_get_dynamic_info (l
, NULL
);
1290 /* Make sure we are not dlopen'ing an object
1291 that has the DF_1_NOOPEN flag set. */
1292 if (__builtin_expect (l
->l_flags_1
& DF_1_NOOPEN
, 0)
1293 && (mode
& __RTLD_DLOPEN
))
1295 /* We are not supposed to load this object. Free all resources. */
1296 __munmap ((void *) l
->l_map_start
, l
->l_map_end
- l
->l_map_start
);
1298 if (!l
->l_libname
->dont_free
)
1299 free (l
->l_libname
);
1301 if (l
->l_phdr_allocated
)
1302 free ((void *) l
->l_phdr
);
1304 errstring
= N_("shared object cannot be dlopen()ed");
1308 if (l
->l_info
[DT_HASH
])
1311 /* If this object has DT_SYMBOLIC set modify now its scope. We don't
1312 have to do this for the main map. */
1313 if (__builtin_expect (l
->l_info
[DT_SYMBOLIC
] != NULL
, 0)
1314 && &l
->l_searchlist
!= l
->l_scope
[0])
1316 /* Create an appropriate searchlist. It contains only this map.
1318 XXX This is the definition of DT_SYMBOLIC in SysVr4. The old
1319 GNU ld.so implementation had a different interpretation which
1320 is more reasonable. We are prepared to add this possibility
1321 back as part of a GNU extension of the ELF format. */
1322 l
->l_symbolic_searchlist
.r_list
=
1323 (struct link_map
**) malloc (sizeof (struct link_map
*));
1325 if (l
->l_symbolic_searchlist
.r_list
== NULL
)
1327 errstring
= N_("cannot create searchlist");
1328 goto call_lose_errno
;
1331 l
->l_symbolic_searchlist
.r_list
[0] = l
;
1332 l
->l_symbolic_searchlist
.r_nlist
= 1;
1334 /* Now move the existing entries one back. */
1335 memmove (&l
->l_scope
[1], &l
->l_scope
[0],
1336 (l
->l_scope_max
- 1) * sizeof (l
->l_scope
[0]));
1338 /* Now add the new entry. */
1339 l
->l_scope
[0] = &l
->l_symbolic_searchlist
;
1342 /* Remember whether this object must be initialized first. */
1343 if (l
->l_flags_1
& DF_1_INITFIRST
)
1344 GL(dl_initfirst
) = l
;
1346 /* Finally the file information. */
1347 l
->l_dev
= st
.st_dev
;
1348 l
->l_ino
= st
.st_ino
;
1350 if (__builtin_expect ((stack_flags
&~ GL(dl_stack_flags
)) & PF_X
, 0))
1352 /* The stack is presently not executable, but this module
1353 requires that it be executable. */
1354 errval
= (*GL(dl_make_stack_executable_hook
)) (stack_endp
);
1358 cannot enable executable stack as shared object requires");
1363 /* When we profile the SONAME might be needed for something else but
1364 loading. Add it right away. */
1365 if (__builtin_expect (GL(dl_profile
) != NULL
, 0)
1366 && l
->l_info
[DT_SONAME
] != NULL
)
1367 add_name_to_object (l
, ((const char *) D_PTR (l
, l_info
[DT_STRTAB
])
1368 + l
->l_info
[DT_SONAME
]->d_un
.d_val
));
1373 /* Print search path. */
1375 print_search_path (struct r_search_path_elem
**list
,
1376 const char *what
, const char *name
)
1378 char buf
[max_dirnamelen
+ max_capstrlen
];
1381 INTUSE(_dl_debug_printf
) (" search path=");
1383 while (*list
!= NULL
&& (*list
)->what
== what
) /* Yes, ==. */
1385 char *endp
= __mempcpy (buf
, (*list
)->dirname
, (*list
)->dirnamelen
);
1388 for (cnt
= 0; cnt
< ncapstr
; ++cnt
)
1389 if ((*list
)->status
[cnt
] != nonexisting
)
1391 char *cp
= __mempcpy (endp
, capstr
[cnt
].str
, capstr
[cnt
].len
);
1392 if (cp
== buf
|| (cp
== buf
+ 1 && buf
[0] == '/'))
1397 _dl_debug_printf_c (first
? "%s" : ":%s", buf
);
1405 _dl_debug_printf_c ("\t\t(%s from file %s)\n", what
,
1406 name
[0] ? name
: rtld_progname
);
1408 _dl_debug_printf_c ("\t\t(%s)\n", what
);
1411 /* Open a file and verify it is an ELF file for this architecture. We
1412 ignore only ELF files for other architectures. Non-ELF files and
1413 ELF files with different header information cause fatal errors since
1414 this could mean there is something wrong in the installation and the
1415 user might want to know about this. */
1417 open_verify (const char *name
, struct filebuf
*fbp
)
1419 /* This is the expected ELF header. */
1420 #define ELF32_CLASS ELFCLASS32
1421 #define ELF64_CLASS ELFCLASS64
1422 #ifndef VALID_ELF_HEADER
1423 # define VALID_ELF_HEADER(hdr,exp,size) (memcmp (hdr, exp, size) == 0)
1424 # define VALID_ELF_OSABI(osabi) (osabi == ELFOSABI_SYSV)
1425 # define VALID_ELF_ABIVERSION(ver) (ver == 0)
1427 static const unsigned char expected
[EI_PAD
] =
1429 [EI_MAG0
] = ELFMAG0
,
1430 [EI_MAG1
] = ELFMAG1
,
1431 [EI_MAG2
] = ELFMAG2
,
1432 [EI_MAG3
] = ELFMAG3
,
1433 [EI_CLASS
] = ELFW(CLASS
),
1434 [EI_DATA
] = byteorder
,
1435 [EI_VERSION
] = EV_CURRENT
,
1436 [EI_OSABI
] = ELFOSABI_SYSV
,
1441 ElfW(Word
) vendorlen
;
1445 } expected_note
= { 4, 16, 1, "GNU" };
1447 /* Initialize it to make the compiler happy. */
1448 const char *errstring
= NULL
;
1451 /* Open the file. We always open files read-only. */
1452 fd
= __open (name
, O_RDONLY
);
1456 ElfW(Phdr
) *phdr
, *ph
;
1457 ElfW(Word
) *abi_note
, abi_note_buf
[8];
1458 unsigned int osversion
;
1461 /* We successfully openened the file. Now verify it is a file
1464 fbp
->len
= __libc_read (fd
, fbp
->buf
, sizeof (fbp
->buf
));
1466 /* This is where the ELF header is loaded. */
1467 assert (sizeof (fbp
->buf
) > sizeof (ElfW(Ehdr
)));
1468 ehdr
= (ElfW(Ehdr
) *) fbp
->buf
;
1470 /* Now run the tests. */
1471 if (__builtin_expect (fbp
->len
< (ssize_t
) sizeof (ElfW(Ehdr
)), 0))
1474 errstring
= (errval
== 0
1475 ? N_("file too short") : N_("cannot read file data"));
1477 lose (errval
, fd
, name
, NULL
, NULL
, errstring
);
1480 /* See whether the ELF header is what we expect. */
1481 if (__builtin_expect (! VALID_ELF_HEADER (ehdr
->e_ident
, expected
,
1484 /* Something is wrong. */
1485 if (*(Elf32_Word
*) &ehdr
->e_ident
!=
1486 #if BYTE_ORDER == LITTLE_ENDIAN
1487 ((ELFMAG0
<< (EI_MAG0
* 8)) |
1488 (ELFMAG1
<< (EI_MAG1
* 8)) |
1489 (ELFMAG2
<< (EI_MAG2
* 8)) |
1490 (ELFMAG3
<< (EI_MAG3
* 8)))
1492 ((ELFMAG0
<< (EI_MAG3
* 8)) |
1493 (ELFMAG1
<< (EI_MAG2
* 8)) |
1494 (ELFMAG2
<< (EI_MAG1
* 8)) |
1495 (ELFMAG3
<< (EI_MAG0
* 8)))
1498 errstring
= N_("invalid ELF header");
1499 else if (ehdr
->e_ident
[EI_CLASS
] != ELFW(CLASS
))
1500 /* This is not a fatal error. On architectures where
1501 32-bit and 64-bit binaries can be run this might
1504 else if (ehdr
->e_ident
[EI_DATA
] != byteorder
)
1506 if (BYTE_ORDER
== BIG_ENDIAN
)
1507 errstring
= N_("ELF file data encoding not big-endian");
1509 errstring
= N_("ELF file data encoding not little-endian");
1511 else if (ehdr
->e_ident
[EI_VERSION
] != EV_CURRENT
)
1513 = N_("ELF file version ident does not match current one");
1514 /* XXX We should be able so set system specific versions which are
1516 else if (!VALID_ELF_OSABI (ehdr
->e_ident
[EI_OSABI
]))
1517 errstring
= N_("ELF file OS ABI invalid");
1518 else if (!VALID_ELF_ABIVERSION (ehdr
->e_ident
[EI_ABIVERSION
]))
1519 errstring
= N_("ELF file ABI version invalid");
1521 /* Otherwise we don't know what went wrong. */
1522 errstring
= N_("internal error");
1527 if (__builtin_expect (ehdr
->e_version
, EV_CURRENT
) != EV_CURRENT
)
1529 errstring
= N_("ELF file version does not match current one");
1532 if (! __builtin_expect (elf_machine_matches_host (ehdr
), 1))
1534 else if (__builtin_expect (ehdr
->e_phentsize
, sizeof (ElfW(Phdr
)))
1535 != sizeof (ElfW(Phdr
)))
1537 errstring
= N_("ELF file's phentsize not the expected size");
1540 else if (__builtin_expect (ehdr
->e_type
, ET_DYN
) != ET_DYN
1541 && __builtin_expect (ehdr
->e_type
, ET_EXEC
) != ET_EXEC
)
1543 errstring
= N_("only ET_DYN and ET_EXEC can be loaded");
1547 maplength
= ehdr
->e_phnum
* sizeof (ElfW(Phdr
));
1548 if (ehdr
->e_phoff
+ maplength
<= (size_t) fbp
->len
)
1549 phdr
= (void *) (fbp
->buf
+ ehdr
->e_phoff
);
1552 phdr
= alloca (maplength
);
1553 __lseek (fd
, ehdr
->e_phoff
, SEEK_SET
);
1554 if ((size_t) __libc_read (fd
, (void *) phdr
, maplength
) != maplength
)
1558 errstring
= N_("cannot read file data");
1563 /* Check .note.ABI-tag if present. */
1564 for (ph
= phdr
; ph
< &phdr
[ehdr
->e_phnum
]; ++ph
)
1565 if (ph
->p_type
== PT_NOTE
&& ph
->p_filesz
== 32 && ph
->p_align
>= 4)
1567 if (ph
->p_offset
+ 32 <= (size_t) fbp
->len
)
1568 abi_note
= (void *) (fbp
->buf
+ ph
->p_offset
);
1571 __lseek (fd
, ph
->p_offset
, SEEK_SET
);
1572 if (__libc_read (fd
, (void *) abi_note_buf
, 32) != 32)
1575 abi_note
= abi_note_buf
;
1578 if (memcmp (abi_note
, &expected_note
, sizeof (expected_note
)))
1581 osversion
= (abi_note
[5] & 0xff) * 65536
1582 + (abi_note
[6] & 0xff) * 256
1583 + (abi_note
[7] & 0xff);
1584 if (abi_note
[4] != __ABI_TAG_OS
1585 || (GL(dl_osversion
) && GL(dl_osversion
) < osversion
))
1589 __set_errno (ENOENT
);
1600 /* Try to open NAME in one of the directories in *DIRSP.
1601 Return the fd, or -1. If successful, fill in *REALNAME
1602 with the malloc'd full directory name. If it turns out
1603 that none of the directories in *DIRSP exists, *DIRSP is
1604 replaced with (void *) -1, and the old value is free()d
1605 if MAY_FREE_DIRS is true. */
1608 open_path (const char *name
, size_t namelen
, int preloaded
,
1609 struct r_search_path_struct
*sps
, char **realname
,
1610 struct filebuf
*fbp
)
1612 struct r_search_path_elem
**dirs
= sps
->dirs
;
1615 const char *current_what
= NULL
;
1618 buf
= alloca (max_dirnamelen
+ max_capstrlen
+ namelen
);
1621 struct r_search_path_elem
*this_dir
= *dirs
;
1628 /* If we are debugging the search for libraries print the path
1629 now if it hasn't happened now. */
1630 if (__builtin_expect (GL(dl_debug_mask
) & DL_DEBUG_LIBS
, 0)
1631 && current_what
!= this_dir
->what
)
1633 current_what
= this_dir
->what
;
1634 print_search_path (dirs
, current_what
, this_dir
->where
);
1637 edp
= (char *) __mempcpy (buf
, this_dir
->dirname
, this_dir
->dirnamelen
);
1638 for (cnt
= 0; fd
== -1 && cnt
< ncapstr
; ++cnt
)
1640 /* Skip this directory if we know it does not exist. */
1641 if (this_dir
->status
[cnt
] == nonexisting
)
1645 ((char *) __mempcpy (__mempcpy (edp
, capstr
[cnt
].str
,
1650 /* Print name we try if this is wanted. */
1651 if (__builtin_expect (GL(dl_debug_mask
) & DL_DEBUG_LIBS
, 0))
1652 INTUSE(_dl_debug_printf
) (" trying file=%s\n", buf
);
1654 fd
= open_verify (buf
, fbp
);
1655 if (this_dir
->status
[cnt
] == unknown
)
1658 this_dir
->status
[cnt
] = existing
;
1661 /* We failed to open machine dependent library. Let's
1662 test whether there is any directory at all. */
1665 buf
[buflen
- namelen
- 1] = '\0';
1667 if (__xstat64 (_STAT_VER
, buf
, &st
) != 0
1668 || ! S_ISDIR (st
.st_mode
))
1669 /* The directory does not exist or it is no directory. */
1670 this_dir
->status
[cnt
] = nonexisting
;
1672 this_dir
->status
[cnt
] = existing
;
1676 /* Remember whether we found any existing directory. */
1677 here_any
|= this_dir
->status
[cnt
] == existing
;
1679 if (fd
!= -1 && __builtin_expect (preloaded
, 0)
1680 && INTUSE(__libc_enable_secure
))
1682 /* This is an extra security effort to make sure nobody can
1683 preload broken shared objects which are in the trusted
1684 directories and so exploit the bugs. */
1687 if (__fxstat64 (_STAT_VER
, fd
, &st
) != 0
1688 || (st
.st_mode
& S_ISUID
) == 0)
1690 /* The shared object cannot be tested for being SUID
1691 or this bit is not set. In this case we must not
1695 /* We simply ignore the file, signal this by setting
1696 the error value which would have been set by `open'. */
1704 *realname
= (char *) malloc (buflen
);
1705 if (*realname
!= NULL
)
1707 memcpy (*realname
, buf
, buflen
);
1712 /* No memory for the name, we certainly won't be able
1713 to load and link it. */
1718 if (here_any
&& (err
= errno
) != ENOENT
&& err
!= EACCES
)
1719 /* The file exists and is readable, but something went wrong. */
1722 /* Remember whether we found anything. */
1725 while (*++dirs
!= NULL
);
1727 /* Remove the whole path if none of the directories exists. */
1728 if (__builtin_expect (! any
, 0))
1730 /* Paths which were allocated using the minimal malloc() in ld.so
1731 must not be freed using the general free() in libc. */
1734 sps
->dirs
= (void *) -1;
1740 /* Map in the shared object file NAME. */
1744 _dl_map_object (struct link_map
*loader
, const char *name
, int preloaded
,
1745 int type
, int trace_mode
, int mode
)
1753 /* Look for this name among those already loaded. */
1754 for (l
= GL(dl_loaded
); l
; l
= l
->l_next
)
1756 /* If the requested name matches the soname of a loaded object,
1757 use that object. Elide this check for names that have not
1759 if (__builtin_expect (l
->l_faked
, 0) != 0)
1761 if (!_dl_name_match_p (name
, l
))
1765 if (__builtin_expect (l
->l_soname_added
, 1)
1766 || l
->l_info
[DT_SONAME
] == NULL
)
1769 soname
= ((const char *) D_PTR (l
, l_info
[DT_STRTAB
])
1770 + l
->l_info
[DT_SONAME
]->d_un
.d_val
);
1771 if (strcmp (name
, soname
) != 0)
1774 /* We have a match on a new name -- cache it. */
1775 add_name_to_object (l
, soname
);
1776 l
->l_soname_added
= 1;
1779 /* We have a match. */
1783 /* Display information if we are debugging. */
1784 if (__builtin_expect (GL(dl_debug_mask
) & DL_DEBUG_FILES
, 0)
1786 INTUSE(_dl_debug_printf
) ("\nfile=%s; needed by %s\n", name
,
1788 ? loader
->l_name
: rtld_progname
);
1790 if (strchr (name
, '/') == NULL
)
1792 /* Search for NAME in several places. */
1794 size_t namelen
= strlen (name
) + 1;
1796 if (__builtin_expect (GL(dl_debug_mask
) & DL_DEBUG_LIBS
, 0))
1797 INTUSE(_dl_debug_printf
) ("find library=%s; searching\n", name
);
1801 /* When the object has the RUNPATH information we don't use any
1803 if (loader
== NULL
|| loader
->l_info
[DT_RUNPATH
] == NULL
)
1805 /* First try the DT_RPATH of the dependent object that caused NAME
1806 to be loaded. Then that object's dependent, and on up. */
1807 for (l
= loader
; fd
== -1 && l
; l
= l
->l_loader
)
1808 if (cache_rpath (l
, &l
->l_rpath_dirs
, DT_RPATH
, "RPATH"))
1809 fd
= open_path (name
, namelen
, preloaded
, &l
->l_rpath_dirs
,
1812 /* If dynamically linked, try the DT_RPATH of the executable
1815 if (fd
== -1 && l
&& l
->l_type
!= lt_loaded
&& l
!= loader
1816 && l
->l_rpath_dirs
.dirs
!= (void *) -1)
1817 fd
= open_path (name
, namelen
, preloaded
, &l
->l_rpath_dirs
,
1821 /* Try the LD_LIBRARY_PATH environment variable. */
1822 if (fd
== -1 && env_path_list
.dirs
!= (void *) -1)
1823 fd
= open_path (name
, namelen
, preloaded
, &env_path_list
,
1826 /* Look at the RUNPATH information for this binary. */
1827 if (fd
== -1 && loader
!= NULL
1828 && cache_rpath (loader
, &loader
->l_runpath_dirs
,
1829 DT_RUNPATH
, "RUNPATH"))
1830 fd
= open_path (name
, namelen
, preloaded
,
1831 &loader
->l_runpath_dirs
, &realname
, &fb
);
1834 && (__builtin_expect (! preloaded
, 1)
1835 || ! INTUSE(__libc_enable_secure
)))
1837 /* Check the list of libraries in the file /etc/ld.so.cache,
1838 for compatibility with Linux's ldconfig program. */
1839 const char *cached
= _dl_load_cache_lookup (name
);
1844 l
= loader
?: GL(dl_loaded
);
1849 /* If the loader has the DF_1_NODEFLIB flag set we must not
1850 use a cache entry from any of these directories. */
1853 /* 'l' is always != NULL for dynamically linked objects. */
1856 __builtin_expect (l
->l_flags_1
& DF_1_NODEFLIB
, 0))
1858 const char *dirp
= system_dirs
;
1859 unsigned int cnt
= 0;
1863 if (memcmp (cached
, dirp
, system_dirs_len
[cnt
]) == 0)
1865 /* The prefix matches. Don't use the entry. */
1870 dirp
+= system_dirs_len
[cnt
] + 1;
1873 while (cnt
< nsystem_dirs_len
);
1878 fd
= open_verify (cached
, &fb
);
1879 if (__builtin_expect (fd
!= -1, 1))
1881 realname
= local_strdup (cached
);
1882 if (realname
== NULL
)
1892 /* Finally, try the default path. */
1894 && ((l
= loader
?: GL(dl_loaded
)) == NULL
1895 || __builtin_expect (!(l
->l_flags_1
& DF_1_NODEFLIB
), 1))
1896 && rtld_search_dirs
.dirs
!= (void *) -1)
1897 fd
= open_path (name
, namelen
, preloaded
, &rtld_search_dirs
,
1900 /* Add another newline when we are tracing the library loading. */
1901 if (__builtin_expect (GL(dl_debug_mask
) & DL_DEBUG_LIBS
, 0))
1902 INTUSE(_dl_debug_printf
) ("\n");
1906 /* The path may contain dynamic string tokens. */
1908 ? expand_dynamic_string_token (loader
, name
)
1909 : local_strdup (name
));
1910 if (realname
== NULL
)
1914 fd
= open_verify (realname
, &fb
);
1915 if (__builtin_expect (fd
, 0) == -1)
1920 if (__builtin_expect (fd
, 0) == -1)
1923 && __builtin_expect (GL(dl_debug_mask
) & DL_DEBUG_PRELINK
, 0) == 0)
1925 /* We haven't found an appropriate library. But since we
1926 are only interested in the list of libraries this isn't
1927 so severe. Fake an entry with all the information we
1929 static const Elf_Symndx dummy_bucket
= STN_UNDEF
;
1931 /* Enter the new object in the list of loaded objects. */
1932 if ((name_copy
= local_strdup (name
)) == NULL
1933 || (l
= _dl_new_object (name_copy
, name
, type
, loader
)) == NULL
)
1934 INTUSE(_dl_signal_error
) (ENOMEM
, name
, NULL
, N_("\
1935 cannot create shared object descriptor"));
1936 /* Signal that this is a faked entry. */
1938 /* Since the descriptor is initialized with zero we do not
1940 l->l_reserved = 0; */
1941 l
->l_buckets
= &dummy_bucket
;
1948 INTUSE(_dl_signal_error
) (errno
, name
, NULL
,
1949 N_("cannot open shared object file"));
1952 void *stack_end
= __libc_stack_end
;
1953 return _dl_map_object_from_fd (name
, fd
, &fb
, realname
, loader
, type
, mode
,
1956 INTDEF (_dl_map_object
)
1960 _dl_rtld_di_serinfo (struct link_map
*loader
, Dl_serinfo
*si
, bool counting
)
1968 unsigned int idx
= 0;
1969 char *allocptr
= (char *) &si
->dls_serpath
[si
->dls_cnt
];
1970 void add_path (const struct r_search_path_struct
*sps
, unsigned int flags
)
1971 # define add_path(sps, flags) add_path(sps, 0) /* XXX */
1973 if (sps
->dirs
!= (void *) -1)
1975 struct r_search_path_elem
**dirs
= sps
->dirs
;
1978 const struct r_search_path_elem
*const r
= *dirs
++;
1982 si
->dls_size
+= r
->dirnamelen
;
1986 Dl_serpath
*const sp
= &si
->dls_serpath
[idx
++];
1987 sp
->dls_name
= allocptr
;
1988 allocptr
= __mempcpy (allocptr
,
1989 r
->dirname
, r
->dirnamelen
- 1);
1991 sp
->dls_flags
= flags
;
1994 while (*dirs
!= NULL
);
1998 /* When the object has the RUNPATH information we don't use any RPATHs. */
1999 if (loader
->l_info
[DT_RUNPATH
] == NULL
)
2001 /* First try the DT_RPATH of the dependent object that caused NAME
2002 to be loaded. Then that object's dependent, and on up. */
2004 struct link_map
*l
= loader
;
2007 if (cache_rpath (l
, &l
->l_rpath_dirs
, DT_RPATH
, "RPATH"))
2008 add_path (&l
->l_rpath_dirs
, XXX_RPATH
);
2013 /* If dynamically linked, try the DT_RPATH of the executable itself. */
2015 if (l
!= NULL
&& l
->l_type
!= lt_loaded
&& l
!= loader
)
2016 if (cache_rpath (l
, &l
->l_rpath_dirs
, DT_RPATH
, "RPATH"))
2017 add_path (&l
->l_rpath_dirs
, XXX_RPATH
);
2020 /* Try the LD_LIBRARY_PATH environment variable. */
2021 add_path (&env_path_list
, XXX_ENV
);
2023 /* Look at the RUNPATH information for this binary. */
2024 if (cache_rpath (loader
, &loader
->l_runpath_dirs
, DT_RUNPATH
, "RUNPATH"))
2025 add_path (&loader
->l_runpath_dirs
, XXX_RUNPATH
);
2028 Here is where ld.so.cache gets checked, but we don't have
2029 a way to indicate that in the results for Dl_serinfo. */
2031 /* Finally, try the default path. */
2032 if (!(loader
->l_flags_1
& DF_1_NODEFLIB
))
2033 add_path (&rtld_search_dirs
, XXX_default
);
2036 /* Count the struct size before the string area, which we didn't
2037 know before we completed dls_cnt. */
2038 si
->dls_size
+= (char *) &si
->dls_serpath
[si
->dls_cnt
] - (char *) si
;