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d66e34cd 1/* Run time dynamic linker.
d614a753 2 Copyright (C) 1995-2020 Free Software Foundation, Inc.
afd4eb37 3 This file is part of the GNU C Library.
d66e34cd 4
afd4eb37 5 The GNU C Library is free software; you can redistribute it and/or
41bdb6e2
AJ
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.
d66e34cd 9
afd4eb37
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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
41bdb6e2 13 Lesser General Public License for more details.
d66e34cd 14
41bdb6e2 15 You should have received a copy of the GNU Lesser General Public
59ba27a6 16 License along with the GNU C Library; if not, see
5a82c748 17 <https://www.gnu.org/licenses/>. */
d66e34cd 18
7d0b1164 19#include <errno.h>
154d10bd 20#include <dlfcn.h>
7dea968e 21#include <fcntl.h>
164a7164 22#include <stdbool.h>
d66e34cd 23#include <stdlib.h>
f51d1dfd 24#include <string.h>
d66e34cd 25#include <unistd.h>
20739e54 26#include <sys/mman.h>
af8bf6bd 27#include <sys/param.h>
ba9fcb3f 28#include <sys/stat.h>
a42195db 29#include <ldsodefs.h>
eb96ffb0 30#include <_itoa.h>
f21acc89 31#include <entry.h>
c94a8080 32#include <fpu_control.h>
db276fa1 33#include <hp-timing.h>
ec999b8e 34#include <libc-lock.h>
f5348425 35#include "dynamic-link.h"
8f480b4b 36#include <dl-librecon.h>
74955460 37#include <unsecvars.h>
5688da55 38#include <dl-cache.h>
2f4db0df 39#include <dl-osinfo.h>
5688da55 40#include <dl-procinfo.h>
f753fa7d 41#include <dl-prop.h>
1bdda52f
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42#include <dl-vdso.h>
43#include <dl-vdso-setup.h>
5f5843e3 44#include <tls.h>
815e6fa3 45#include <stap-probe.h>
30950a5f 46#include <stackinfo.h>
329ea513 47#include <not-cancel.h>
4c6e0415 48#include <array_length.h>
ec935dea 49#include <libc-early-init.h>
f5348425 50
a853022c 51#include <assert.h>
f5348425 52
1e372ded
AZ
53/* Only enables rtld profiling for architectures which provides non generic
54 hp-timing support. The generic support requires either syscall
55 (clock_gettime), which will incur in extra overhead on loading time.
56 Using vDSO is also an option, but it will require extra support on loader
57 to setup the vDSO pointer before its usage. */
58#if HP_TIMING_INLINE
59# define RLTD_TIMING_DECLARE(var, classifier,...) \
60 classifier hp_timing_t var __VA_ARGS__
61# define RTLD_TIMING_VAR(var) RLTD_TIMING_DECLARE (var, )
62# define RTLD_TIMING_SET(var, value) (var) = (value)
63# define RTLD_TIMING_REF(var) &(var)
64
65static inline void
66rtld_timer_start (hp_timing_t *var)
67{
68 HP_TIMING_NOW (*var);
69}
70
71static inline void
72rtld_timer_stop (hp_timing_t *var, hp_timing_t start)
73{
74 hp_timing_t stop;
75 HP_TIMING_NOW (stop);
76 HP_TIMING_DIFF (*var, start, stop);
77}
78
79static inline void
80rtld_timer_accum (hp_timing_t *sum, hp_timing_t start)
81{
82 hp_timing_t stop;
83 rtld_timer_stop (&stop, start);
84 HP_TIMING_ACCUM_NT(*sum, stop);
85}
86#else
87# define RLTD_TIMING_DECLARE(var, classifier...)
88# define RTLD_TIMING_SET(var, value)
89# define RTLD_TIMING_VAR(var)
90# define RTLD_TIMING_REF(var) 0
91# define rtld_timer_start(var)
92# define rtld_timer_stop(var, start)
93# define rtld_timer_accum(sum, start)
94#endif
95
6ce3881d
RM
96/* Avoid PLT use for our local calls at startup. */
97extern __typeof (__mempcpy) __mempcpy attribute_hidden;
98
99/* GCC has mental blocks about _exit. */
100extern __typeof (_exit) exit_internal asm ("_exit") attribute_hidden;
101#define _exit exit_internal
102
fd26970f 103/* Helper function to handle errors while resolving symbols. */
c84142e8
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104static void print_unresolved (int errcode, const char *objname,
105 const char *errsting);
106
107/* Helper function to handle errors when a version is missing. */
108static void print_missing_version (int errcode, const char *objname,
109 const char *errsting);
fd26970f 110
db276fa1 111/* Print the various times we collected. */
1e372ded 112static void print_statistics (const hp_timing_t *total_timep);
ea278354 113
4c6e0415
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114/* Length limits for names and paths, to protect the dynamic linker,
115 particularly when __libc_enable_secure is active. */
116#ifdef NAME_MAX
117# define SECURE_NAME_LIMIT NAME_MAX
118#else
119# define SECURE_NAME_LIMIT 255
120#endif
121#ifdef PATH_MAX
122# define SECURE_PATH_LIMIT PATH_MAX
123#else
124# define SECURE_PATH_LIMIT 1024
125#endif
126
127/* Strings containing colon-separated lists of audit modules. */
128struct audit_list
129{
130 /* Array of strings containing colon-separated path lists. Each
131 audit module needs its own namespace, so pre-allocate the largest
132 possible list. */
133 const char *audit_strings[DL_NNS];
134
135 /* Number of entries added to audit_strings. */
136 size_t length;
137
138 /* Index into the audit_strings array (for the iteration phase). */
139 size_t current_index;
140
141 /* Tail of audit_strings[current_index] which still needs
142 processing. */
143 const char *current_tail;
144
145 /* Scratch buffer for returning a name which is part of the strings
146 in audit_strings. */
147 char fname[SECURE_NAME_LIMIT];
148};
149
150/* Creates an empty audit list. */
151static void audit_list_init (struct audit_list *);
152
153/* Add a string to the end of the audit list, for later parsing. Must
154 not be called after audit_list_next. */
155static void audit_list_add_string (struct audit_list *, const char *);
156
8f7a75d7
FW
157/* Add the audit strings from the link map, found in the dynamic
158 segment at TG (either DT_AUDIT and DT_DEPAUDIT). Must be called
159 before audit_list_next. */
160static void audit_list_add_dynamic_tag (struct audit_list *,
161 struct link_map *,
162 unsigned int tag);
163
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FW
164/* Extract the next audit module from the audit list. Only modules
165 for which dso_name_valid_for_suid is true are returned. Must be
8f7a75d7
FW
166 called after all the audit_list_add_string,
167 audit_list_add_dynamic_tags calls. */
4c6e0415 168static const char *audit_list_next (struct audit_list *);
74780cf6 169
ea278354
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170/* This is a list of all the modes the dynamic loader can be in. */
171enum mode { normal, list, verify, trace };
172
173/* Process all environments variables the dynamic linker must recognize.
174 Since all of them start with `LD_' we are a bit smarter while finding
175 all the entries. */
4c6e0415 176static void process_envvars (enum mode *modep, struct audit_list *);
ea278354 177
11986c68 178#ifdef DL_ARGV_NOT_RELRO
22aa06a5 179int _dl_argc attribute_hidden;
11986c68 180char **_dl_argv = NULL;
22aa06a5
RM
181/* Nonzero if we were run directly. */
182unsigned int _dl_skip_args attribute_hidden;
11986c68 183#else
22aa06a5 184int _dl_argc attribute_relro attribute_hidden;
697afbe1 185char **_dl_argv attribute_relro = NULL;
22aa06a5 186unsigned int _dl_skip_args attribute_relro attribute_hidden;
11986c68 187#endif
4243cbea 188rtld_hidden_data_def (_dl_argv)
5c82e15e 189
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190#ifndef THREAD_SET_STACK_GUARD
191/* Only exported for architectures that don't store the stack guard canary
192 in thread local area. */
193uintptr_t __stack_chk_guard attribute_relro;
194#endif
195
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196/* Only exported for architectures that don't store the pointer guard
197 value in thread local area. */
198uintptr_t __pointer_chk_guard_local
199 attribute_relro attribute_hidden __attribute__ ((nocommon));
200#ifndef THREAD_SET_POINTER_GUARD
201strong_alias (__pointer_chk_guard_local, __pointer_chk_guard)
202#endif
203
6d0ba622
FW
204/* Check that AT_SECURE=0, or that the passed name does not contain
205 directories and is not overly long. Reject empty names
206 unconditionally. */
207static bool
208dso_name_valid_for_suid (const char *p)
209{
210 if (__glibc_unlikely (__libc_enable_secure))
211 {
212 /* Ignore pathnames with directories for AT_SECURE=1
213 programs, and also skip overlong names. */
214 size_t len = strlen (p);
215 if (len >= SECURE_NAME_LIMIT || memchr (p, '/', len) != NULL)
216 return false;
217 }
218 return *p != '\0';
219}
827b7087 220
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FW
221static void
222audit_list_init (struct audit_list *list)
9dcafc55 223{
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FW
224 list->length = 0;
225 list->current_index = 0;
226 list->current_tail = NULL;
227}
9dcafc55 228
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229static void
230audit_list_add_string (struct audit_list *list, const char *string)
81b82fb9 231{
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232 /* Empty strings do not load anything. */
233 if (*string == '\0')
234 return;
81b82fb9 235
4c6e0415
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236 if (list->length == array_length (list->audit_strings))
237 _dl_fatal_printf ("Fatal glibc error: Too many audit modules requested\n");
81b82fb9 238
4c6e0415 239 list->audit_strings[list->length++] = string;
81b82fb9 240
4c6e0415
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241 /* Initialize processing of the first string for
242 audit_list_next. */
243 if (list->length == 1)
244 list->current_tail = string;
81b82fb9
FW
245}
246
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FW
247static void
248audit_list_add_dynamic_tag (struct audit_list *list, struct link_map *main_map,
249 unsigned int tag)
250{
251 ElfW(Dyn) *info = main_map->l_info[ADDRIDX (tag)];
252 const char *strtab = (const char *) D_PTR (main_map, l_info[DT_STRTAB]);
253 if (info != NULL)
254 audit_list_add_string (list, strtab + info->d_un.d_val);
255}
256
81b82fb9 257static const char *
4c6e0415 258audit_list_next (struct audit_list *list)
81b82fb9 259{
4c6e0415
FW
260 if (list->current_tail == NULL)
261 return NULL;
262
263 while (true)
81b82fb9 264 {
4c6e0415
FW
265 /* Advance to the next string in audit_strings if the current
266 string has been exhausted. */
267 while (*list->current_tail == '\0')
81b82fb9 268 {
4c6e0415
FW
269 ++list->current_index;
270 if (list->current_index == list->length)
81b82fb9 271 {
4c6e0415
FW
272 list->current_tail = NULL;
273 return NULL;
81b82fb9 274 }
4c6e0415 275 list->current_tail = list->audit_strings[list->current_index];
81b82fb9 276 }
81b82fb9 277
4c6e0415
FW
278 /* Split the in-string audit list at the next colon colon. */
279 size_t len = strcspn (list->current_tail, ":");
280 if (len > 0 && len < sizeof (list->fname))
281 {
282 memcpy (list->fname, list->current_tail, len);
283 list->fname[len] = '\0';
284 }
285 else
286 /* Mark the name as unusable for dso_name_valid_for_suid. */
287 list->fname[0] = '\0';
288
289 /* Skip over the substring and the following delimiter. */
290 list->current_tail += len;
291 if (*list->current_tail == ':')
292 ++list->current_tail;
293
294 /* If the name is valid, return it. */
295 if (dso_name_valid_for_suid (list->fname))
296 return list->fname;
297
298 /* Otherwise wrap around to find the next list element. . */
81b82fb9 299 }
81b82fb9
FW
300}
301
ce6e047f 302#ifndef HAVE_INLINED_SYSCALLS
39778c6c
UD
303/* Set nonzero during loading and initialization of executable and
304 libraries, cleared before the executable's entry point runs. This
305 must not be initialized to nonzero, because the unused dynamic
306 linker loaded in for libc.so's "ld.so.1" dep will provide the
307 definition seen by libc.so's initializer; that value must be zero,
308 and will be since that dynamic linker's _dl_start and dl_main will
309 never be called. */
e6caf4e1 310int _dl_starting_up = 0;
9cf27b8d 311rtld_hidden_def (_dl_starting_up)
ce6e047f 312#endif
39778c6c 313
d6b5d570
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314/* This is the structure which defines all variables global to ld.so
315 (except those which cannot be added for some reason). */
5688da55
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316struct rtld_global _rtld_global =
317 {
30950a5f
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318 /* Generally the default presumption without further information is an
319 * executable stack but this is not true for all platforms. */
320 ._dl_stack_flags = DEFAULT_STACK_PERMS,
ffa8d2a0 321#ifdef _LIBC_REENTRANT
22c83193 322 ._dl_load_lock = _RTLD_LOCK_RECURSIVE_INITIALIZER,
5a2a1d75 323 ._dl_load_write_lock = _RTLD_LOCK_RECURSIVE_INITIALIZER,
ffa8d2a0 324#endif
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325 ._dl_nns = 1,
326 ._dl_ns =
327 {
bea9b193 328#ifdef _LIBC_REENTRANT
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UD
329 [LM_ID_BASE] = { ._ns_unique_sym_table
330 = { .lock = _RTLD_LOCK_RECURSIVE_INITIALIZER } }
bea9b193 331#endif
415ac3df 332 }
5688da55 333 };
27a754a9
UD
334/* If we would use strong_alias here the compiler would see a
335 non-hidden definition. This would undo the effect of the previous
336 declaration. So spell out was strong_alias does plus add the
337 visibility attribute. */
338extern struct rtld_global _rtld_local
339 __attribute__ ((alias ("_rtld_global"), visibility ("hidden")));
c0fb8a56 340
afdca0f2
UD
341
342/* This variable is similar to _rtld_local, but all values are
343 read-only after relocation. */
344struct rtld_global_ro _rtld_global_ro attribute_relro =
345 {
c31e278f
UD
346 /* Get architecture specific initializer. */
347#include <dl-procinfo.c>
afdca0f2
UD
348#ifdef NEED_DL_SYSINFO
349 ._dl_sysinfo = DL_SYSINFO_DEFAULT,
350#endif
dd70526e 351 ._dl_debug_fd = STDERR_FILENO,
afdca0f2
UD
352 ._dl_use_load_bias = -2,
353 ._dl_correct_cache_id = _DL_CACHE_DEFAULT_ID,
ff08fc59 354#if !HAVE_TUNABLES
afdca0f2 355 ._dl_hwcap_mask = HWCAP_IMPORTANT,
ff08fc59 356#endif
afdca0f2
UD
357 ._dl_lazy = 1,
358 ._dl_fpu_control = _FPU_DEFAULT,
02d46fc4 359 ._dl_pagesize = EXEC_PAGESIZE,
73d65cc3 360 ._dl_inhibit_cache = 0,
154d10bd
UD
361
362 /* Function pointers. */
154d10bd 363 ._dl_debug_printf = _dl_debug_printf,
ab97ee8f 364 ._dl_mcount = _dl_mcount,
021723ab 365 ._dl_lookup_symbol_x = _dl_lookup_symbol_x,
9dcafc55 366 ._dl_open = _dl_open,
93025f93 367 ._dl_close = _dl_close,
7c22c7ec
UD
368 ._dl_tls_get_addr_soft = _dl_tls_get_addr_soft,
369#ifdef HAVE_DL_DISCOVER_OSVERSION
370 ._dl_discover_osversion = _dl_discover_osversion
371#endif
afdca0f2
UD
372 };
373/* If we would use strong_alias here the compiler would see a
374 non-hidden definition. This would undo the effect of the previous
375 declaration. So spell out was strong_alias does plus add the
376 visibility attribute. */
377extern struct rtld_global_ro _rtld_local_ro
378 __attribute__ ((alias ("_rtld_global_ro"), visibility ("hidden")));
379
380
67ddea92 381static void dl_main (const ElfW(Phdr) *phdr, ElfW(Word) phnum,
3a56ea26 382 ElfW(Addr) *user_entry, ElfW(auxv_t) *auxv);
d66e34cd 383
392a6b52 384/* These two variables cannot be moved into .data.rel.ro. */
d6b5d570
UD
385static struct libname_list _dl_rtld_libname;
386static struct libname_list _dl_rtld_libname2;
86d2c878 387
db276fa1 388/* Variable for statistics. */
1e372ded
AZ
389RLTD_TIMING_DECLARE (relocate_time, static);
390RLTD_TIMING_DECLARE (load_time, static, attribute_relro);
391RLTD_TIMING_DECLARE (start_time, static, attribute_relro);
db276fa1 392
2a76f7ef
UD
393/* Additional definitions needed by TLS initialization. */
394#ifdef TLS_INIT_HELPER
395TLS_INIT_HELPER
5e289179
UD
396#endif
397
398/* Helper function for syscall implementation. */
399#ifdef DL_SYSINFO_IMPLEMENTATION
400DL_SYSINFO_IMPLEMENTATION
2a76f7ef
UD
401#endif
402
01d8e36d
UD
403/* Before ld.so is relocated we must not access variables which need
404 relocations. This means variables which are exported. Variables
405 declared as static are fine. If we can mark a variable hidden this
27a754a9 406 is fine, too. The latter is important here. We can avoid setting
01d8e36d
UD
407 up a temporary link map for ld.so if we can mark _rtld_global as
408 hidden. */
11bf311e 409#ifdef PI_STATIC_AND_HIDDEN
01d8e36d
UD
410# define DONT_USE_BOOTSTRAP_MAP 1
411#endif
412
413#ifdef DONT_USE_BOOTSTRAP_MAP
414static ElfW(Addr) _dl_start_final (void *arg);
415#else
4874b009
RM
416struct dl_start_final_info
417{
418 struct link_map l;
1e372ded 419 RTLD_TIMING_VAR (start_time);
4874b009 420};
01d8e36d 421static ElfW(Addr) _dl_start_final (void *arg,
4874b009 422 struct dl_start_final_info *info);
01d8e36d 423#endif
6a1db4ff 424
65da9563
RM
425/* These defined magically in the linker script. */
426extern char _begin[] attribute_hidden;
eec8b6ca 427extern char _etext[] attribute_hidden;
65da9563
RM
428extern char _end[] attribute_hidden;
429
430
b1dbbaa4
RM
431#ifdef RTLD_START
432RTLD_START
433#else
eaad82e0 434# error "sysdeps/MACHINE/dl-machine.h fails to define RTLD_START"
b1dbbaa4
RM
435#endif
436
c2248c44
RM
437/* This is the second half of _dl_start (below). It can be inlined safely
438 under DONT_USE_BOOTSTRAP_MAP, where it is careful not to make any GOT
439 references. When the tools don't permit us to avoid using a GOT entry
440 for _dl_rtld_global (no attribute_hidden support), we must make sure
441 this function is not inlined (see below). */
442
443#ifdef DONT_USE_BOOTSTRAP_MAP
444static inline ElfW(Addr) __attribute__ ((always_inline))
445_dl_start_final (void *arg)
446#else
447static ElfW(Addr) __attribute__ ((noinline))
4874b009 448_dl_start_final (void *arg, struct dl_start_final_info *info)
c2248c44
RM
449#endif
450{
451 ElfW(Addr) start_addr;
c2248c44 452
1e372ded
AZ
453 /* If it hasn't happen yet record the startup time. */
454 rtld_timer_start (&start_time);
455#if !defined DONT_USE_BOOTSTRAP_MAP
456 RTLD_TIMING_SET (start_time, info->start_time);
4874b009 457#endif
c2248c44
RM
458
459 /* Transfer data about ourselves to the permanent link_map structure. */
460#ifndef DONT_USE_BOOTSTRAP_MAP
4874b009
RM
461 GL(dl_rtld_map).l_addr = info->l.l_addr;
462 GL(dl_rtld_map).l_ld = info->l.l_ld;
463 memcpy (GL(dl_rtld_map).l_info, info->l.l_info,
c2248c44 464 sizeof GL(dl_rtld_map).l_info);
4874b009 465 GL(dl_rtld_map).l_mach = info->l.l_mach;
82221992 466 GL(dl_rtld_map).l_relocated = 1;
c2248c44
RM
467#endif
468 _dl_setup_hash (&GL(dl_rtld_map));
c0f62c56 469 GL(dl_rtld_map).l_real = &GL(dl_rtld_map);
c2248c44
RM
470 GL(dl_rtld_map).l_map_start = (ElfW(Addr)) _begin;
471 GL(dl_rtld_map).l_map_end = (ElfW(Addr)) _end;
eec8b6ca 472 GL(dl_rtld_map).l_text_end = (ElfW(Addr)) _etext;
c2248c44 473 /* Copy the TLS related data if necessary. */
11bf311e 474#ifndef DONT_USE_BOOTSTRAP_MAP
3d8c8bff 475# if NO_TLS_OFFSET != 0
299601a1 476 GL(dl_rtld_map).l_tls_offset = NO_TLS_OFFSET;
c2248c44 477# endif
c2248c44
RM
478#endif
479
ea4f25a7
UD
480 /* Initialize the stack end variable. */
481 __libc_stack_end = __builtin_frame_address (0);
482
c2248c44
RM
483 /* Call the OS-dependent function to set up life so we can do things like
484 file access. It will call `dl_main' (below) to do all the real work
485 of the dynamic linker, and then unwind our frame and run the user
486 entry point on the same stack we entered on. */
ecdeaac0 487 start_addr = _dl_sysdep_start (arg, &dl_main);
c2248c44 488
a1ffb40e 489 if (__glibc_unlikely (GLRO(dl_debug_mask) & DL_DEBUG_STATISTICS))
39b04aa3 490 {
1e372ded
AZ
491 RTLD_TIMING_VAR (rtld_total_time);
492 rtld_timer_stop (&rtld_total_time, start_time);
493 print_statistics (RTLD_TIMING_REF(rtld_total_time));
39b04aa3 494 }
c2248c44
RM
495
496 return start_addr;
497}
498
630bf491 499static ElfW(Addr) __attribute_used__
d66e34cd
RM
500_dl_start (void *arg)
501{
01d8e36d
UD
502#ifdef DONT_USE_BOOTSTRAP_MAP
503# define bootstrap_map GL(dl_rtld_map)
504#else
4874b009
RM
505 struct dl_start_final_info info;
506# define bootstrap_map info.l
739d440d 507#endif
d66e34cd 508
b1dbbaa4 509 /* This #define produces dynamic linking inline functions for
2f978feb
UD
510 bootstrap relocation instead of general-purpose relocation.
511 Since ld.so must not have any undefined symbols the result
512 is trivial: always the map of ld.so itself. */
b1dbbaa4 513#define RTLD_BOOTSTRAP
b8818ab5
L
514#define BOOTSTRAP_MAP (&bootstrap_map)
515#define RESOLVE_MAP(sym, version, flags) BOOTSTRAP_MAP
b1dbbaa4
RM
516#include "dynamic-link.h"
517
4874b009 518#ifdef DONT_USE_BOOTSTRAP_MAP
1e372ded 519 rtld_timer_start (&start_time);
4874b009 520#else
1e372ded 521 rtld_timer_start (&info.start_time);
4874b009 522#endif
db276fa1 523
e66d0a4c
UD
524 /* Partly clean the `bootstrap_map' structure up. Don't use
525 `memset' since it might not be built in or inlined and we cannot
526 make function calls at this point. Use '__builtin_memset' if we
01d8e36d
UD
527 know it is available. We do not have to clear the memory if we
528 do not have to use the temporary bootstrap_map. Global variables
529 are initialized to zero by default. */
530#ifndef DONT_USE_BOOTSTRAP_MAP
531# ifdef HAVE_BUILTIN_MEMSET
e66d0a4c 532 __builtin_memset (bootstrap_map.l_info, '\0', sizeof (bootstrap_map.l_info));
01d8e36d 533# else
ce460d04 534 for (size_t cnt = 0;
264ec183
UD
535 cnt < sizeof (bootstrap_map.l_info) / sizeof (bootstrap_map.l_info[0]);
536 ++cnt)
537 bootstrap_map.l_info[cnt] = 0;
01d8e36d 538# endif
e66d0a4c 539#endif
264ec183 540
d66e34cd 541 /* Figure out the run-time load address of the dynamic linker itself. */
86d2c878 542 bootstrap_map.l_addr = elf_machine_load_address ();
d66e34cd 543
47707456
UD
544 /* Read our own dynamic section and fill in the info array. */
545 bootstrap_map.l_ld = (void *) bootstrap_map.l_addr + elf_machine_dynamic ();
479aa8ec 546 elf_get_dynamic_info (&bootstrap_map, NULL);
d66e34cd 547
11bf311e 548#if NO_TLS_OFFSET != 0
299601a1
UD
549 bootstrap_map.l_tls_offset = NO_TLS_OFFSET;
550#endif
551
d66e34cd 552#ifdef ELF_MACHINE_BEFORE_RTLD_RELOC
86d2c878 553 ELF_MACHINE_BEFORE_RTLD_RELOC (bootstrap_map.l_info);
d66e34cd
RM
554#endif
555
32e6df36
UD
556 if (bootstrap_map.l_addr || ! bootstrap_map.l_info[VALIDX(DT_GNU_PRELINKED)])
557 {
558 /* Relocate ourselves so we can do normal function calls and
559 data access using the global offset table. */
560
3a62d00d 561 ELF_DYNAMIC_RELOCATE (&bootstrap_map, 0, 0, 0);
32e6df36 562 }
f85f3563 563 bootstrap_map.l_relocated = 1;
421f82e5 564
ea7eb7e3
UD
565 /* Please note that we don't allow profiling of this object and
566 therefore need not test whether we have to allocate the array
567 for the relocation results (as done in dl-reloc.c). */
421f82e5 568
d66e34cd
RM
569 /* Now life is sane; we can call functions and access global data.
570 Set up to use the operating system facilities, and find out from
571 the operating system's program loader where to find the program
6a1db4ff
UD
572 header table in core. Put the rest of _dl_start into a separate
573 function, that way the compiler cannot put accesses to the GOT
574 before ELF_DYNAMIC_RELOCATE. */
3a0ecccb
FW
575
576 __rtld_malloc_init_stubs ();
577
c0282c06 578 {
01d8e36d
UD
579#ifdef DONT_USE_BOOTSTRAP_MAP
580 ElfW(Addr) entry = _dl_start_final (arg);
581#else
4874b009 582 ElfW(Addr) entry = _dl_start_final (arg, &info);
01d8e36d 583#endif
c0282c06
UD
584
585#ifndef ELF_MACHINE_START_ADDRESS
586# define ELF_MACHINE_START_ADDRESS(map, start) (start)
587#endif
588
7cb92a99 589 return ELF_MACHINE_START_ADDRESS (GL(dl_ns)[LM_ID_BASE]._ns_loaded, entry);
c0282c06 590 }
6a1db4ff
UD
591}
592
593
d66e34cd 594
d66e34cd
RM
595/* Now life is peachy; we can do all normal operations.
596 On to the real work. */
597
993b3242
UD
598/* Some helper functions. */
599
600/* Arguments to relocate_doit. */
601struct relocate_args
602{
603 struct link_map *l;
2ca285b0 604 int reloc_mode;
993b3242
UD
605};
606
607struct map_args
608{
609 /* Argument to map_doit. */
acf869f4 610 const char *str;
f04b9a68 611 struct link_map *loader;
f04b9a68 612 int mode;
993b3242 613 /* Return value of map_doit. */
f04b9a68 614 struct link_map *map;
993b3242
UD
615};
616
9dcafc55
UD
617struct dlmopen_args
618{
619 const char *fname;
620 struct link_map *map;
621};
622
623struct lookup_args
624{
625 const char *name;
626 struct link_map *map;
627 void *result;
628};
629
993b3242
UD
630/* Arguments to version_check_doit. */
631struct version_check_args
632{
993b3242 633 int doexit;
145b8413 634 int dotrace;
993b3242
UD
635};
636
637static void
638relocate_doit (void *a)
639{
640 struct relocate_args *args = (struct relocate_args *) a;
641
2ca285b0 642 _dl_relocate_object (args->l, args->l->l_scope, args->reloc_mode, 0);
993b3242
UD
643}
644
645static void
646map_doit (void *a)
647{
be935610 648 struct map_args *args = (struct map_args *) a;
798212a0
PP
649 int type = (args->mode == __RTLD_OPENEXEC) ? lt_executable : lt_library;
650 args->map = _dl_map_object (args->loader, args->str, type, 0,
8e9f92e9 651 args->mode, LM_ID_BASE);
993b3242
UD
652}
653
9dcafc55
UD
654static void
655dlmopen_doit (void *a)
656{
657 struct dlmopen_args *args = (struct dlmopen_args *) a;
8e9f92e9
AS
658 args->map = _dl_open (args->fname,
659 (RTLD_LAZY | __RTLD_DLOPEN | __RTLD_AUDIT
660 | __RTLD_SECURE),
4243cbea 661 dl_main, LM_ID_NEWLM, _dl_argc, _dl_argv,
9dcafc55
UD
662 __environ);
663}
664
665static void
666lookup_doit (void *a)
667{
668 struct lookup_args *args = (struct lookup_args *) a;
669 const ElfW(Sym) *ref = NULL;
670 args->result = NULL;
671 lookup_t l = _dl_lookup_symbol_x (args->name, args->map, &ref,
672 args->map->l_local_scope, NULL, 0,
673 DL_LOOKUP_RETURN_NEWEST, NULL);
674 if (ref != NULL)
675 args->result = DL_SYMBOL_ADDRESS (l, ref);
676}
677
993b3242
UD
678static void
679version_check_doit (void *a)
680{
be935610 681 struct version_check_args *args = (struct version_check_args *) a;
c0f62c56
UD
682 if (_dl_check_all_versions (GL(dl_ns)[LM_ID_BASE]._ns_loaded, 1,
683 args->dotrace) && args->doexit)
993b3242
UD
684 /* We cannot start the application. Abort now. */
685 _exit (1);
686}
687
ce37fa88
UD
688
689static inline struct link_map *
690find_needed (const char *name)
691{
c0f62c56
UD
692 struct r_scope_elem *scope = &GL(dl_ns)[LM_ID_BASE]._ns_loaded->l_searchlist;
693 unsigned int n = scope->r_nlist;
ce37fa88 694
be935610 695 while (n-- > 0)
c0f62c56
UD
696 if (_dl_name_match_p (name, scope->r_list[n]))
697 return scope->r_list[n];
ce37fa88
UD
698
699 /* Should never happen. */
700 return NULL;
701}
702
703static int
704match_version (const char *string, struct link_map *map)
705{
a42195db 706 const char *strtab = (const void *) D_PTR (map, l_info[DT_STRTAB]);
ce37fa88
UD
707 ElfW(Verdef) *def;
708
b0982c4a 709#define VERDEFTAG (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGIDX (DT_VERDEF))
ce37fa88
UD
710 if (map->l_info[VERDEFTAG] == NULL)
711 /* The file has no symbol versioning. */
712 return 0;
713
714 def = (ElfW(Verdef) *) ((char *) map->l_addr
715 + map->l_info[VERDEFTAG]->d_un.d_ptr);
716 while (1)
717 {
718 ElfW(Verdaux) *aux = (ElfW(Verdaux) *) ((char *) def + def->vd_aux);
719
720 /* Compare the version strings. */
721 if (strcmp (string, strtab + aux->vda_name) == 0)
722 /* Bingo! */
723 return 1;
724
725 /* If no more definitions we failed to find what we want. */
726 if (def->vd_next == 0)
727 break;
728
729 /* Next definition. */
730 def = (ElfW(Verdef) *) ((char *) def + def->vd_next);
731 }
732
733 return 0;
734}
735
9dcafc55
UD
736static bool tls_init_tp_called;
737
738static void *
739init_tls (void)
740{
741 /* Number of elements in the static TLS block. */
742 GL(dl_tls_static_nelem) = GL(dl_tls_max_dtv_idx);
743
744 /* Do not do this twice. The audit interface might have required
745 the DTV interfaces to be set up early. */
746 if (GL(dl_initial_dtv) != NULL)
747 return NULL;
748
749 /* Allocate the array which contains the information about the
750 dtv slots. We allocate a few entries more than needed to
751 avoid the need for reallocation. */
752 size_t nelem = GL(dl_tls_max_dtv_idx) + 1 + TLS_SLOTINFO_SURPLUS;
753
754 /* Allocate. */
755 GL(dl_tls_dtv_slotinfo_list) = (struct dtv_slotinfo_list *)
756 calloc (sizeof (struct dtv_slotinfo_list)
757 + nelem * sizeof (struct dtv_slotinfo), 1);
758 /* No need to check the return value. If memory allocation failed
759 the program would have been terminated. */
760
761 struct dtv_slotinfo *slotinfo = GL(dl_tls_dtv_slotinfo_list)->slotinfo;
762 GL(dl_tls_dtv_slotinfo_list)->len = nelem;
763 GL(dl_tls_dtv_slotinfo_list)->next = NULL;
764
765 /* Fill in the information from the loaded modules. No namespace
766 but the base one can be filled at this time. */
767 assert (GL(dl_ns)[LM_ID_BASE + 1]._ns_loaded == NULL);
768 int i = 0;
769 for (struct link_map *l = GL(dl_ns)[LM_ID_BASE]._ns_loaded; l != NULL;
770 l = l->l_next)
771 if (l->l_tls_blocksize != 0)
772 {
773 /* This is a module with TLS data. Store the map reference.
774 The generation counter is zero. */
775 slotinfo[i].map = l;
776 /* slotinfo[i].gen = 0; */
777 ++i;
778 }
779 assert (i == GL(dl_tls_max_dtv_idx));
780
781 /* Compute the TLS offsets for the various blocks. */
782 _dl_determine_tlsoffset ();
783
784 /* Construct the static TLS block and the dtv for the initial
785 thread. For some platforms this will include allocating memory
786 for the thread descriptor. The memory for the TLS block will
787 never be freed. It should be allocated accordingly. The dtv
788 array can be changed if dynamic loading requires it. */
789 void *tcbp = _dl_allocate_tls_storage ();
790 if (tcbp == NULL)
791 _dl_fatal_printf ("\
f648728c 792cannot allocate TLS data structures for initial thread\n");
9dcafc55
UD
793
794 /* Store for detection of the special case by __tls_get_addr
795 so it knows not to pass this dtv to the normal realloc. */
796 GL(dl_initial_dtv) = GET_DTV (tcbp);
797
3d8c8bff 798 /* And finally install it for the main thread. */
774f9285 799 const char *lossage = TLS_INIT_TP (tcbp);
a1ffb40e 800 if (__glibc_unlikely (lossage != NULL))
9dcafc55
UD
801 _dl_fatal_printf ("cannot set up thread-local storage: %s\n", lossage);
802 tls_init_tp_called = true;
803
804 return tcbp;
805}
9dcafc55 806
20fe49b9 807static unsigned int
acf869f4 808do_preload (const char *fname, struct link_map *main_map, const char *where)
20fe49b9
UD
809{
810 const char *objname;
811 const char *err_str = NULL;
812 struct map_args args;
74780cf6 813 bool malloced;
20fe49b9
UD
814
815 args.str = fname;
816 args.loader = main_map;
8e9f92e9 817 args.mode = __RTLD_SECURE;
20fe49b9
UD
818
819 unsigned int old_nloaded = GL(dl_ns)[LM_ID_BASE]._ns_nloaded;
820
74780cf6 821 (void) _dl_catch_error (&objname, &err_str, &malloced, map_doit, &args);
a1ffb40e 822 if (__glibc_unlikely (err_str != NULL))
20fe49b9
UD
823 {
824 _dl_error_printf ("\
4db5b08f
MS
825ERROR: ld.so: object '%s' from %s cannot be preloaded (%s): ignored.\n",
826 fname, where, err_str);
20fe49b9
UD
827 /* No need to call free, this is still before
828 the libc's malloc is used. */
829 }
830 else if (GL(dl_ns)[LM_ID_BASE]._ns_nloaded != old_nloaded)
831 /* It is no duplicate. */
832 return 1;
833
834 /* Nothing loaded. */
835 return 0;
836}
837
334fcf2a
UD
838#if defined SHARED && defined _LIBC_REENTRANT \
839 && defined __rtld_lock_default_lock_recursive
20fe49b9
UD
840static void
841rtld_lock_default_lock_recursive (void *lock)
334fcf2a
UD
842{
843 __rtld_lock_default_lock_recursive (lock);
844}
845
20fe49b9
UD
846static void
847rtld_lock_default_unlock_recursive (void *lock)
334fcf2a
UD
848{
849 __rtld_lock_default_unlock_recursive (lock);
850}
851#endif
852
853
4c48ef06
UD
854static void
855security_init (void)
856{
857 /* Set up the stack checker's canary. */
965cb60a 858 uintptr_t stack_chk_guard = _dl_setup_stack_chk_guard (_dl_random);
4c48ef06
UD
859#ifdef THREAD_SET_STACK_GUARD
860 THREAD_SET_STACK_GUARD (stack_chk_guard);
861#else
862 __stack_chk_guard = stack_chk_guard;
863#endif
864
865 /* Set up the pointer guard as well, if necessary. */
a014cecd
FW
866 uintptr_t pointer_chk_guard
867 = _dl_setup_pointer_guard (_dl_random, stack_chk_guard);
4c48ef06 868#ifdef THREAD_SET_POINTER_GUARD
a014cecd 869 THREAD_SET_POINTER_GUARD (pointer_chk_guard);
4c48ef06 870#endif
a014cecd 871 __pointer_chk_guard_local = pointer_chk_guard;
965cb60a
UD
872
873 /* We do not need the _dl_random value anymore. The less
874 information we leave behind, the better, so clear the
875 variable. */
876 _dl_random = NULL;
4c48ef06
UD
877}
878
1bdda52f 879#include <setup-vdso.h>
4c48ef06 880
392a6b52
UD
881/* The library search path. */
882static const char *library_path attribute_relro;
883/* The list preloaded objects. */
884static const char *preloadlist attribute_relro;
885/* Nonzero if information about versions has to be printed. */
886static int version_info attribute_relro;
8692ebdb
DN
887/* The preload list passed as a command argument. */
888static const char *preloadarg attribute_relro;
a1a9d215 889
6d0ba622
FW
890/* The LD_PRELOAD environment variable gives list of libraries
891 separated by white space or colons that are loaded before the
892 executable's dependencies and prepended to the global scope list.
893 (If the binary is running setuid all elements containing a '/' are
894 ignored since it is insecure.) Return the number of preloads
8692ebdb 895 performed. Ditto for --preload command argument. */
6d0ba622 896unsigned int
8692ebdb
DN
897handle_preload_list (const char *preloadlist, struct link_map *main_map,
898 const char *where)
6d0ba622
FW
899{
900 unsigned int npreloads = 0;
901 const char *p = preloadlist;
902 char fname[SECURE_PATH_LIMIT];
903
904 while (*p != '\0')
905 {
906 /* Split preload list at space/colon. */
907 size_t len = strcspn (p, " :");
908 if (len > 0 && len < sizeof (fname))
909 {
910 memcpy (fname, p, len);
911 fname[len] = '\0';
912 }
913 else
914 fname[0] = '\0';
915
916 /* Skip over the substring and the following delimiter. */
917 p += len;
918 if (*p != '\0')
919 ++p;
920
921 if (dso_name_valid_for_suid (fname))
8692ebdb 922 npreloads += do_preload (fname, main_map, where);
6d0ba622
FW
923 }
924 return npreloads;
925}
926
3b856d09
FW
927/* Called if the audit DSO cannot be used: if it does not have the
928 appropriate interfaces, or it expects a more recent version library
929 version than what the dynamic linker provides. */
930static void
931unload_audit_module (struct link_map *map, int original_tls_idx)
932{
933#ifndef NDEBUG
934 Lmid_t ns = map->l_ns;
935#endif
936 _dl_close (map);
937
938 /* Make sure the namespace has been cleared entirely. */
939 assert (GL(dl_ns)[ns]._ns_loaded == NULL);
940 assert (GL(dl_ns)[ns]._ns_nloaded == 0);
941
942 GL(dl_tls_max_dtv_idx) = original_tls_idx;
943}
944
945/* Called to print an error message if loading of an audit module
946 failed. */
947static void
948report_audit_module_load_error (const char *name, const char *err_str,
949 bool malloced)
950{
951 _dl_error_printf ("\
952ERROR: ld.so: object '%s' cannot be loaded as audit interface: %s; ignored.\n",
953 name, err_str);
954 if (malloced)
955 free ((char *) err_str);
956}
957
958/* Load one audit module. */
959static void
960load_audit_module (const char *name, struct audit_ifaces **last_audit)
961{
962 int original_tls_idx = GL(dl_tls_max_dtv_idx);
963
964 struct dlmopen_args dlmargs;
965 dlmargs.fname = name;
966 dlmargs.map = NULL;
967
968 const char *objname;
969 const char *err_str = NULL;
970 bool malloced;
971 _dl_catch_error (&objname, &err_str, &malloced, dlmopen_doit, &dlmargs);
972 if (__glibc_unlikely (err_str != NULL))
973 {
974 report_audit_module_load_error (name, err_str, malloced);
975 return;
976 }
977
978 struct lookup_args largs;
979 largs.name = "la_version";
980 largs.map = dlmargs.map;
981 _dl_catch_error (&objname, &err_str, &malloced, lookup_doit, &largs);
982 if (__glibc_likely (err_str != NULL))
983 {
984 unload_audit_module (dlmargs.map, original_tls_idx);
985 report_audit_module_load_error (name, err_str, malloced);
986 return;
987 }
988
989 unsigned int (*laversion) (unsigned int) = largs.result;
990
991 /* A null symbol indicates that something is very wrong with the
992 loaded object because defined symbols are supposed to have a
993 valid, non-null address. */
994 assert (laversion != NULL);
995
996 unsigned int lav = laversion (LAV_CURRENT);
997 if (lav == 0)
998 {
999 /* Only print an error message if debugging because this can
1000 happen deliberately. */
1001 if (GLRO(dl_debug_mask) & DL_DEBUG_FILES)
1002 _dl_debug_printf ("\
1003file=%s [%lu]; audit interface function la_version returned zero; ignored.\n",
1004 dlmargs.map->l_name, dlmargs.map->l_ns);
1005 unload_audit_module (dlmargs.map, original_tls_idx);
1006 return;
1007 }
1008
1009 if (lav > LAV_CURRENT)
1010 {
1011 _dl_debug_printf ("\
1012ERROR: audit interface '%s' requires version %d (maximum supported version %d); ignored.\n",
1013 name, lav, LAV_CURRENT);
1014 unload_audit_module (dlmargs.map, original_tls_idx);
1015 return;
1016 }
1017
1018 enum { naudit_ifaces = 8 };
1019 union
1020 {
1021 struct audit_ifaces ifaces;
1022 void (*fptr[naudit_ifaces]) (void);
1023 } *newp = malloc (sizeof (*newp));
1024 if (newp == NULL)
1025 _dl_fatal_printf ("Out of memory while loading audit modules\n");
1026
1027 /* Names of the auditing interfaces. All in one
1028 long string. */
1029 static const char audit_iface_names[] =
1030 "la_activity\0"
1031 "la_objsearch\0"
1032 "la_objopen\0"
1033 "la_preinit\0"
1034#if __ELF_NATIVE_CLASS == 32
1035 "la_symbind32\0"
1036#elif __ELF_NATIVE_CLASS == 64
1037 "la_symbind64\0"
1038#else
1039# error "__ELF_NATIVE_CLASS must be defined"
1040#endif
1041#define STRING(s) __STRING (s)
1042 "la_" STRING (ARCH_LA_PLTENTER) "\0"
1043 "la_" STRING (ARCH_LA_PLTEXIT) "\0"
1044 "la_objclose\0";
1045 unsigned int cnt = 0;
1046 const char *cp = audit_iface_names;
1047 do
1048 {
1049 largs.name = cp;
1050 _dl_catch_error (&objname, &err_str, &malloced, lookup_doit, &largs);
1051
1052 /* Store the pointer. */
1053 if (err_str == NULL && largs.result != NULL)
c7bf5cea 1054 newp->fptr[cnt] = largs.result;
3b856d09
FW
1055 else
1056 newp->fptr[cnt] = NULL;
1057 ++cnt;
1058
1059 cp = rawmemchr (cp, '\0') + 1;
1060 }
1061 while (*cp != '\0');
1062 assert (cnt == naudit_ifaces);
1063
1064 /* Now append the new auditing interface to the list. */
1065 newp->ifaces.next = NULL;
1066 if (*last_audit == NULL)
1067 *last_audit = GLRO(dl_audit) = &newp->ifaces;
1068 else
1069 *last_audit = (*last_audit)->next = &newp->ifaces;
c7bf5cea 1070
e1d559f3
FW
1071 /* The dynamic linker link map is statically allocated, so the
1072 cookie in _dl_new_object has not happened. */
1073 link_map_audit_state (&GL (dl_rtld_map), GLRO (dl_naudit))->cookie
c7bf5cea
FW
1074 = (intptr_t) &GL (dl_rtld_map);
1075
3b856d09
FW
1076 ++GLRO(dl_naudit);
1077
1078 /* Mark the DSO as being used for auditing. */
1079 dlmargs.map->l_auditing = 1;
1080}
1081
1082/* Notify the the audit modules that the object MAP has already been
1083 loaded. */
1084static void
1085notify_audit_modules_of_loaded_object (struct link_map *map)
1086{
1087 struct audit_ifaces *afct = GLRO(dl_audit);
1088 for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt)
1089 {
1090 if (afct->objopen != NULL)
1091 {
e1d559f3
FW
1092 struct auditstate *state = link_map_audit_state (map, cnt);
1093 state->bindflags = afct->objopen (map, LM_ID_BASE, &state->cookie);
1094 map->l_audit_any_plt |= state->bindflags != 0;
3b856d09
FW
1095 }
1096
1097 afct = afct->next;
1098 }
1099}
1100
1101/* Load all audit modules. */
1102static void
4c6e0415 1103load_audit_modules (struct link_map *main_map, struct audit_list *audit_list)
3b856d09
FW
1104{
1105 struct audit_ifaces *last_audit = NULL;
3b856d09
FW
1106
1107 while (true)
1108 {
4c6e0415 1109 const char *name = audit_list_next (audit_list);
3b856d09
FW
1110 if (name == NULL)
1111 break;
1112 load_audit_module (name, &last_audit);
1113 }
1114
1115 /* Notify audit modules of the initially loaded modules (the main
1116 program and the dynamic linker itself). */
1117 if (GLRO(dl_naudit) > 0)
1118 {
1119 notify_audit_modules_of_loaded_object (main_map);
1120 notify_audit_modules_of_loaded_object (&GL(dl_rtld_map));
1121 }
1122}
1123
d66e34cd 1124static void
266180eb 1125dl_main (const ElfW(Phdr) *phdr,
72f70279 1126 ElfW(Word) phnum,
3a56ea26
AK
1127 ElfW(Addr) *user_entry,
1128 ElfW(auxv_t) *auxv)
d66e34cd 1129{
266180eb 1130 const ElfW(Phdr) *ph;
ea278354 1131 enum mode mode;
c0f62c56 1132 struct link_map *main_map;
14bab8de
UD
1133 size_t file_size;
1134 char *file;
164a7164 1135 bool has_interp = false;
77aba05b 1136 unsigned int i;
164a7164
UD
1137 bool prelinked = false;
1138 bool rtld_is_main = false;
9dcafc55 1139 void *tcbp = NULL;
d66e34cd 1140
4c6e0415
FW
1141 struct audit_list audit_list;
1142 audit_list_init (&audit_list);
1143
adc12574 1144 GL(dl_init_static_tls) = &_dl_nothread_init_static_tls;
adc12574 1145
334fcf2a
UD
1146#if defined SHARED && defined _LIBC_REENTRANT \
1147 && defined __rtld_lock_default_lock_recursive
1148 GL(dl_rtld_lock_recursive) = rtld_lock_default_lock_recursive;
1149 GL(dl_rtld_unlock_recursive) = rtld_lock_default_unlock_recursive;
1150#endif
1151
c70ba488
RM
1152 /* The explicit initialization here is cheaper than processing the reloc
1153 in the _rtld_local definition's initializer. */
1154 GL(dl_make_stack_executable_hook) = &_dl_make_stack_executable;
1155
ea278354 1156 /* Process the environment variable which control the behaviour. */
4c6e0415 1157 process_envvars (&mode, &audit_list);
3996f34b 1158
ce6e047f 1159#ifndef HAVE_INLINED_SYSCALLS
46ec036d 1160 /* Set up a flag which tells we are just starting. */
9cf27b8d 1161 _dl_starting_up = 1;
ce6e047f 1162#endif
46ec036d 1163
a16956f3 1164 if (*user_entry == (ElfW(Addr)) ENTRY_POINT)
0200214b
RM
1165 {
1166 /* Ho ho. We are not the program interpreter! We are the program
1167 itself! This means someone ran ld.so as a command. Well, that
1168 might be convenient to do sometimes. We support it by
1169 interpreting the args like this:
1170
1171 ld.so PROGRAM ARGS...
1172
1173 The first argument is the name of a file containing an ELF
1174 executable we will load and run with the following arguments.
1175 To simplify life here, PROGRAM is searched for using the
1176 normal rules for shared objects, rather than $PATH or anything
1177 like that. We just load it and use its entry point; we don't
1178 pay attention to its PT_INTERP command (we are the interpreter
1179 ourselves). This is an easy way to test a new ld.so before
1180 installing it. */
164a7164 1181 rtld_is_main = true;
421f82e5 1182
ffee1316 1183 /* Note the place where the dynamic linker actually came from. */
e6caf4e1 1184 GL(dl_rtld_map).l_name = rtld_progname;
6a76c115 1185
fd26970f 1186 while (_dl_argc > 1)
4243cbea 1187 if (! strcmp (_dl_argv[1], "--list"))
fd26970f
UD
1188 {
1189 mode = list;
afdca0f2 1190 GLRO(dl_lazy) = -1; /* This means do no dependency analysis. */
61965e9b 1191
fd26970f
UD
1192 ++_dl_skip_args;
1193 --_dl_argc;
4243cbea 1194 ++_dl_argv;
fd26970f 1195 }
4243cbea 1196 else if (! strcmp (_dl_argv[1], "--verify"))
fd26970f
UD
1197 {
1198 mode = verify;
6a76c115 1199
73d65cc3
SP
1200 ++_dl_skip_args;
1201 --_dl_argc;
4243cbea 1202 ++_dl_argv;
73d65cc3 1203 }
4243cbea 1204 else if (! strcmp (_dl_argv[1], "--inhibit-cache"))
73d65cc3
SP
1205 {
1206 GLRO(dl_inhibit_cache) = 1;
fd26970f
UD
1207 ++_dl_skip_args;
1208 --_dl_argc;
4243cbea 1209 ++_dl_argv;
fd26970f 1210 }
4243cbea 1211 else if (! strcmp (_dl_argv[1], "--library-path")
e6caf4e1 1212 && _dl_argc > 2)
880f421f 1213 {
4243cbea 1214 library_path = _dl_argv[2];
880f421f 1215
310930c1
UD
1216 _dl_skip_args += 2;
1217 _dl_argc -= 2;
4243cbea 1218 _dl_argv += 2;
310930c1 1219 }
4243cbea 1220 else if (! strcmp (_dl_argv[1], "--inhibit-rpath")
e6caf4e1 1221 && _dl_argc > 2)
310930c1 1222 {
4243cbea 1223 GLRO(dl_inhibit_rpath) = _dl_argv[2];
310930c1 1224
74780cf6
UD
1225 _dl_skip_args += 2;
1226 _dl_argc -= 2;
4243cbea 1227 _dl_argv += 2;
74780cf6 1228 }
4243cbea 1229 else if (! strcmp (_dl_argv[1], "--audit") && _dl_argc > 2)
74780cf6 1230 {
4c6e0415 1231 audit_list_add_string (&audit_list, _dl_argv[2]);
74780cf6 1232
8692ebdb
DN
1233 _dl_skip_args += 2;
1234 _dl_argc -= 2;
1235 _dl_argv += 2;
1236 }
1237 else if (! strcmp (_dl_argv[1], "--preload") && _dl_argc > 2)
1238 {
1239 preloadarg = _dl_argv[2];
880f421f
UD
1240 _dl_skip_args += 2;
1241 _dl_argc -= 2;
4243cbea 1242 _dl_argv += 2;
880f421f 1243 }
fd26970f
UD
1244 else
1245 break;
d66e34cd 1246
61eb22d3
UD
1247 /* If we have no further argument the program was called incorrectly.
1248 Grant the user some education. */
1249 if (_dl_argc < 2)
35fc382a 1250 _dl_fatal_printf ("\
2bcf29ba 1251Usage: ld.so [OPTION]... EXECUTABLE-FILE [ARGS-FOR-PROGRAM...]\n\
61eb22d3
UD
1252You have invoked `ld.so', the helper program for shared library executables.\n\
1253This program usually lives in the file `/lib/ld.so', and special directives\n\
1254in executable files using ELF shared libraries tell the system's program\n\
1255loader to load the helper program from this file. This helper program loads\n\
1256the shared libraries needed by the program executable, prepares the program\n\
1257to run, and runs it. You may invoke this helper program directly from the\n\
1258command line to load and run an ELF executable file; this is like executing\n\
1259that file itself, but always uses this helper program from the file you\n\
1260specified, instead of the helper program file specified in the executable\n\
1261file you run. This is mostly of use for maintainers to test new versions\n\
2bcf29ba
UD
1262of this helper program; chances are you did not intend to run this program.\n\
1263\n\
b0a01055
UD
1264 --list list all dependencies and how they are resolved\n\
1265 --verify verify that given object really is a dynamically linked\n\
3a56ea26 1266 object we can handle\n\
73d65cc3 1267 --inhibit-cache Do not use " LD_SO_CACHE "\n\
b0a01055 1268 --library-path PATH use given PATH instead of content of the environment\n\
3a56ea26 1269 variable LD_LIBRARY_PATH\n\
fcf70d41 1270 --inhibit-rpath LIST ignore RUNPATH and RPATH information in object names\n\
3a56ea26 1271 in LIST\n\
8692ebdb
DN
1272 --audit LIST use objects named in LIST as auditors\n\
1273 --preload LIST preload objects named in LIST\n");
61eb22d3 1274
0200214b
RM
1275 ++_dl_skip_args;
1276 --_dl_argc;
4243cbea 1277 ++_dl_argv;
91f62ce6 1278
c70ba488
RM
1279 /* The initialization of _dl_stack_flags done below assumes the
1280 executable's PT_GNU_STACK may have been honored by the kernel, and
1281 so a PT_GNU_STACK with PF_X set means the stack started out with
1282 execute permission. However, this is not really true if the
1283 dynamic linker is the executable the kernel loaded. For this
1284 case, we must reinitialize _dl_stack_flags to match the dynamic
1285 linker itself. If the dynamic linker was built with a
1286 PT_GNU_STACK, then the kernel may have loaded us with a
1287 nonexecutable stack that we will have to make executable when we
1288 load the program below unless it has a PT_GNU_STACK indicating
1289 nonexecutable stack is ok. */
1290
1291 for (ph = phdr; ph < &phdr[phnum]; ++ph)
1292 if (ph->p_type == PT_GNU_STACK)
1293 {
1294 GL(dl_stack_flags) = ph->p_flags;
1295 break;
1296 }
1297
9a821cf9 1298 if (__builtin_expect (mode, normal) == verify)
2de99474 1299 {
8e17ea58
UD
1300 const char *objname;
1301 const char *err_str = NULL;
993b3242 1302 struct map_args args;
74780cf6 1303 bool malloced;
2de99474 1304
e6caf4e1 1305 args.str = rtld_progname;
f04b9a68 1306 args.loader = NULL;
f04b9a68 1307 args.mode = __RTLD_OPENEXEC;
74780cf6
UD
1308 (void) _dl_catch_error (&objname, &err_str, &malloced, map_doit,
1309 &args);
a1ffb40e 1310 if (__glibc_unlikely (err_str != NULL))
e6caf4e1
UD
1311 /* We don't free the returned string, the programs stops
1312 anyway. */
1313 _exit (EXIT_FAILURE);
2de99474
UD
1314 }
1315 else
db276fa1 1316 {
1e372ded
AZ
1317 RTLD_TIMING_VAR (start);
1318 rtld_timer_start (&start);
798212a0 1319 _dl_map_object (NULL, rtld_progname, lt_executable, 0,
c0f62c56 1320 __RTLD_OPENEXEC, LM_ID_BASE);
1e372ded 1321 rtld_timer_stop (&load_time, start);
db276fa1 1322 }
2de99474 1323
c0f62c56
UD
1324 /* Now the map for the main executable is available. */
1325 main_map = GL(dl_ns)[LM_ID_BASE]._ns_loaded;
1326
f3fd569c
DL
1327 if (__builtin_expect (mode, normal) == normal
1328 && GL(dl_rtld_map).l_info[DT_SONAME] != NULL
01f16ab0
UD
1329 && main_map->l_info[DT_SONAME] != NULL
1330 && strcmp ((const char *) D_PTR (&GL(dl_rtld_map), l_info[DT_STRTAB])
1331 + GL(dl_rtld_map).l_info[DT_SONAME]->d_un.d_val,
1332 (const char *) D_PTR (main_map, l_info[DT_STRTAB])
1333 + main_map->l_info[DT_SONAME]->d_un.d_val) == 0)
1334 _dl_fatal_printf ("loader cannot load itself\n");
1335
c0f62c56
UD
1336 phdr = main_map->l_phdr;
1337 phnum = main_map->l_phnum;
143e2b96
UD
1338 /* We overwrite here a pointer to a malloc()ed string. But since
1339 the malloc() implementation used at this point is the dummy
1340 implementations which has no real free() function it does not
1341 makes sense to free the old string first. */
c0f62c56
UD
1342 main_map->l_name = (char *) "";
1343 *user_entry = main_map->l_entry;
3a56ea26 1344
bc58236c 1345#ifdef HAVE_AUX_VECTOR
3a56ea26
AK
1346 /* Adjust the on-stack auxiliary vector so that it looks like the
1347 binary was executed directly. */
bc58236c 1348 for (ElfW(auxv_t) *av = auxv; av->a_type != AT_NULL; av++)
3a56ea26
AK
1349 switch (av->a_type)
1350 {
1351 case AT_PHDR:
4dd019e3 1352 av->a_un.a_val = (uintptr_t) phdr;
3a56ea26
AK
1353 break;
1354 case AT_PHNUM:
1355 av->a_un.a_val = phnum;
1356 break;
1357 case AT_ENTRY:
1358 av->a_un.a_val = *user_entry;
1359 break;
5c349950
PP
1360 case AT_EXECFN:
1361 av->a_un.a_val = (uintptr_t) _dl_argv[0];
1362 break;
3a56ea26 1363 }
bc58236c 1364#endif
0200214b
RM
1365 }
1366 else
1367 {
1368 /* Create a link_map for the executable itself.
1369 This will be what dlopen on "" returns. */
9fbdeb41
UD
1370 main_map = _dl_new_object ((char *) "", "", lt_executable, NULL,
1371 __RTLD_OPENEXEC, LM_ID_BASE);
9dcafc55 1372 assert (main_map != NULL);
c0f62c56
UD
1373 main_map->l_phdr = phdr;
1374 main_map->l_phnum = phnum;
1375 main_map->l_entry = *user_entry;
da832465 1376
f0967738
AK
1377 /* Even though the link map is not yet fully initialized we can add
1378 it to the map list since there are no possible users running yet. */
1379 _dl_add_to_namespace_list (main_map, LM_ID_BASE);
fa41c84d 1380 assert (main_map == GL(dl_ns)[LM_ID_BASE]._ns_loaded);
f0967738 1381
61e0617a
UD
1382 /* At this point we are in a bit of trouble. We would have to
1383 fill in the values for l_dev and l_ino. But in general we
1384 do not know where the file is. We also do not handle AT_EXECFD
1385 even if it would be passed up.
1386
1387 We leave the values here defined to 0. This is normally no
1388 problem as the program code itself is normally no shared
1389 object and therefore cannot be loaded dynamically. Nothing
1390 prevent the use of dynamic binaries and in these situations
1391 we might get problems. We might not be able to find out
1392 whether the object is already loaded. But since there is no
1393 easy way out and because the dynamic binary must also not
1394 have an SONAME we ignore this program for now. If it becomes
1395 a problem we can force people using SONAMEs. */
1396
97a51d8a
UD
1397 /* We delay initializing the path structure until we got the dynamic
1398 information for the program. */
0200214b
RM
1399 }
1400
c0f62c56
UD
1401 main_map->l_map_end = 0;
1402 main_map->l_text_end = 0;
052b6a6c 1403 /* Perhaps the executable has no PT_LOAD header entries at all. */
c0f62c56 1404 main_map->l_map_start = ~0;
c0f62c56
UD
1405 /* And it was opened directly. */
1406 ++main_map->l_direct_opencount;
052b6a6c 1407
0200214b 1408 /* Scan the program header table for the dynamic section. */
72f70279 1409 for (ph = phdr; ph < &phdr[phnum]; ++ph)
0200214b
RM
1410 switch (ph->p_type)
1411 {
da832465
UD
1412 case PT_PHDR:
1413 /* Find out the load address. */
c0f62c56 1414 main_map->l_addr = (ElfW(Addr)) phdr - ph->p_vaddr;
da832465 1415 break;
0200214b
RM
1416 case PT_DYNAMIC:
1417 /* This tells us where to find the dynamic section,
1418 which tells us everything we need to do. */
c0f62c56 1419 main_map->l_ld = (void *) main_map->l_addr + ph->p_vaddr;
0200214b
RM
1420 break;
1421 case PT_INTERP:
1422 /* This "interpreter segment" was used by the program loader to
1423 find the program interpreter, which is this program itself, the
1424 dynamic linker. We note what name finds us, so that a future
1425 dlopen call or DT_NEEDED entry, for something that wants to link
1426 against the dynamic linker as a shared library, will know that
1427 the shared object is already loaded. */
c0f62c56 1428 _dl_rtld_libname.name = ((const char *) main_map->l_addr
be935610 1429 + ph->p_vaddr);
752a2a50 1430 /* _dl_rtld_libname.next = NULL; Already zero. */
d6b5d570 1431 GL(dl_rtld_map).l_libname = &_dl_rtld_libname;
f41c8091
UD
1432
1433 /* Ordinarilly, we would get additional names for the loader from
1434 our DT_SONAME. This can't happen if we were actually linked as
1435 a static executable (detect this case when we have no DYNAMIC).
1436 If so, assume the filename component of the interpreter path to
1437 be our SONAME, and add it to our name list. */
d6b5d570 1438 if (GL(dl_rtld_map).l_ld == NULL)
f41c8091 1439 {
88794e30
UD
1440 const char *p = NULL;
1441 const char *cp = _dl_rtld_libname.name;
1442
1443 /* Find the filename part of the path. */
1444 while (*cp != '\0')
1445 if (*cp++ == '/')
1446 p = cp;
1447
1448 if (p != NULL)
f41c8091 1449 {
88794e30 1450 _dl_rtld_libname2.name = p;
752a2a50 1451 /* _dl_rtld_libname2.next = NULL; Already zero. */
f41c8091
UD
1452 _dl_rtld_libname.next = &_dl_rtld_libname2;
1453 }
1454 }
1455
164a7164 1456 has_interp = true;
0200214b 1457 break;
052b6a6c 1458 case PT_LOAD:
052b6a6c
UD
1459 {
1460 ElfW(Addr) mapstart;
2373b30e
UD
1461 ElfW(Addr) allocend;
1462
1463 /* Remember where the main program starts in memory. */
b92e3780
UD
1464 mapstart = (main_map->l_addr
1465 + (ph->p_vaddr & ~(GLRO(dl_pagesize) - 1)));
c0f62c56
UD
1466 if (main_map->l_map_start > mapstart)
1467 main_map->l_map_start = mapstart;
2373b30e
UD
1468
1469 /* Also where it ends. */
c0f62c56
UD
1470 allocend = main_map->l_addr + ph->p_vaddr + ph->p_memsz;
1471 if (main_map->l_map_end < allocend)
1472 main_map->l_map_end = allocend;
1473 if ((ph->p_flags & PF_X) && allocend > main_map->l_text_end)
1474 main_map->l_text_end = allocend;
052b6a6c
UD
1475 }
1476 break;
9dcafc55 1477
a334319f 1478 case PT_TLS:
aed283dd
UD
1479 if (ph->p_memsz > 0)
1480 {
1481 /* Note that in the case the dynamic linker we duplicate work
1482 here since we read the PT_TLS entry already in
1483 _dl_start_final. But the result is repeatable so do not
1484 check for this special but unimportant case. */
c0f62c56
UD
1485 main_map->l_tls_blocksize = ph->p_memsz;
1486 main_map->l_tls_align = ph->p_align;
99fe3b0e 1487 if (ph->p_align == 0)
c0f62c56 1488 main_map->l_tls_firstbyte_offset = 0;
99fe3b0e 1489 else
c0f62c56
UD
1490 main_map->l_tls_firstbyte_offset = (ph->p_vaddr
1491 & (ph->p_align - 1));
1492 main_map->l_tls_initimage_size = ph->p_filesz;
1493 main_map->l_tls_initimage = (void *) ph->p_vaddr;
aed283dd
UD
1494
1495 /* This image gets the ID one. */
c0f62c56 1496 GL(dl_tls_max_dtv_idx) = main_map->l_tls_modid = 1;
aed283dd 1497 }
9dcafc55
UD
1498 break;
1499
ecdeaac0
RM
1500 case PT_GNU_STACK:
1501 GL(dl_stack_flags) = ph->p_flags;
1502 break;
e8ed861d
UD
1503
1504 case PT_GNU_RELRO:
c0f62c56
UD
1505 main_map->l_relro_addr = ph->p_vaddr;
1506 main_map->l_relro_size = ph->p_memsz;
e8ed861d 1507 break;
f753fa7d
L
1508
1509 case PT_NOTE:
1510 if (_rtld_process_pt_note (main_map, ph))
1511 _dl_error_printf ("\
1512ERROR: '%s': cannot process note segment.\n", _dl_argv[0]);
1513 break;
0200214b 1514 }
11bf311e
UD
1515
1516 /* Adjust the address of the TLS initialization image in case
1517 the executable is actually an ET_DYN object. */
1518 if (main_map->l_tls_initimage != NULL)
1519 main_map->l_tls_initimage
1520 = (char *) main_map->l_tls_initimage + main_map->l_addr;
c0f62c56
UD
1521 if (! main_map->l_map_end)
1522 main_map->l_map_end = ~0;
1523 if (! main_map->l_text_end)
1524 main_map->l_text_end = ~0;
d6b5d570 1525 if (! GL(dl_rtld_map).l_libname && GL(dl_rtld_map).l_name)
c84142e8
UD
1526 {
1527 /* We were invoked directly, so the program might not have a
1528 PT_INTERP. */
d6b5d570 1529 _dl_rtld_libname.name = GL(dl_rtld_map).l_name;
f0967738 1530 /* _dl_rtld_libname.next = NULL; Already zero. */
d6b5d570 1531 GL(dl_rtld_map).l_libname = &_dl_rtld_libname;
c84142e8 1532 }
ffee1316 1533 else
d6b5d570 1534 assert (GL(dl_rtld_map).l_libname); /* How else did we get here? */
0200214b 1535
9dcafc55
UD
1536 /* If the current libname is different from the SONAME, add the
1537 latter as well. */
1538 if (GL(dl_rtld_map).l_info[DT_SONAME] != NULL
1539 && strcmp (GL(dl_rtld_map).l_libname->name,
1540 (const char *) D_PTR (&GL(dl_rtld_map), l_info[DT_STRTAB])
1541 + GL(dl_rtld_map).l_info[DT_SONAME]->d_un.d_val) != 0)
1542 {
1543 static struct libname_list newname;
1544 newname.name = ((char *) D_PTR (&GL(dl_rtld_map), l_info[DT_STRTAB])
1545 + GL(dl_rtld_map).l_info[DT_SONAME]->d_un.d_ptr);
1546 newname.next = NULL;
1547 newname.dont_free = 1;
1548
1549 assert (GL(dl_rtld_map).l_libname->next == NULL);
1550 GL(dl_rtld_map).l_libname->next = &newname;
1551 }
1552 /* The ld.so must be relocated since otherwise loading audit modules
1553 will fail since they reuse the very same ld.so. */
1554 assert (GL(dl_rtld_map).l_relocated);
1555
9a51759b
UD
1556 if (! rtld_is_main)
1557 {
1558 /* Extract the contents of the dynamic section for easy access. */
c0f62c56 1559 elf_get_dynamic_info (main_map, NULL);
efec5079 1560 /* Set up our cache of pointers into the hash table. */
c0f62c56 1561 _dl_setup_hash (main_map);
9a51759b 1562 }
0200214b 1563
9a821cf9 1564 if (__builtin_expect (mode, normal) == verify)
e2102c14
UD
1565 {
1566 /* We were called just to verify that this is a dynamic
1567 executable using us as the program interpreter. Exit with an
1568 error if we were not able to load the binary or no interpreter
1569 is specified (i.e., this is no dynamically linked binary. */
c0f62c56 1570 if (main_map->l_ld == NULL)
e2102c14 1571 _exit (1);
e2102c14
UD
1572
1573 /* We allow here some platform specific code. */
1574#ifdef DISTINGUISH_LIB_VERSIONS
1575 DISTINGUISH_LIB_VERSIONS;
1576#endif
eb406346 1577 _exit (has_interp ? 0 : 2);
e2102c14
UD
1578 }
1579
ab1d521d 1580 struct link_map **first_preload = &GL(dl_rtld_map).l_next;
ab1d521d
RM
1581 /* Set up the data structures for the system-supplied DSO early,
1582 so they can influence _dl_init_paths. */
9cee5585 1583 setup_vdso (main_map, &first_preload);
ab1d521d 1584
1bdda52f
AZ
1585 /* With vDSO setup we can initialize the function pointers. */
1586 setup_vdso_pointers ();
1587
ab1d521d 1588#ifdef DL_SYSDEP_OSCHECK
ceb809dc 1589 DL_SYSDEP_OSCHECK (_dl_fatal_printf);
ab1d521d
RM
1590#endif
1591
1592 /* Initialize the data structures for the search paths for shared
1593 objects. */
1594 _dl_init_paths (library_path);
97a51d8a 1595
9dcafc55 1596 /* Initialize _r_debug. */
29f97654
UD
1597 struct r_debug *r = _dl_debug_initialize (GL(dl_rtld_map).l_addr,
1598 LM_ID_BASE);
9dcafc55
UD
1599 r->r_state = RT_CONSISTENT;
1600
0200214b 1601 /* Put the link_map for ourselves on the chain so it can be found by
ceb2d9aa 1602 name. Note that at this point the global chain of link maps contains
d6b5d570
UD
1603 exactly one element, which is pointed to by dl_loaded. */
1604 if (! GL(dl_rtld_map).l_name)
ffee1316
RM
1605 /* If not invoked directly, the dynamic linker shared object file was
1606 found by the PT_INTERP name. */
d6b5d570
UD
1607 GL(dl_rtld_map).l_name = (char *) GL(dl_rtld_map).l_libname->name;
1608 GL(dl_rtld_map).l_type = lt_library;
c0f62c56
UD
1609 main_map->l_next = &GL(dl_rtld_map);
1610 GL(dl_rtld_map).l_prev = main_map;
1611 ++GL(dl_ns)[LM_ID_BASE]._ns_nloaded;
e8ed861d 1612 ++GL(dl_load_adds);
0200214b 1613
97fd3a30
UD
1614 /* If LD_USE_LOAD_BIAS env variable has not been seen, default
1615 to not using bias for non-prelinked PIEs and libraries
1616 and using it for executables or prelinked PIEs or libraries. */
afdca0f2 1617 if (GLRO(dl_use_load_bias) == (ElfW(Addr)) -2)
c0f62c56 1618 GLRO(dl_use_load_bias) = main_map->l_addr == 0 ? -1 : 0;
97fd3a30 1619
553eca26 1620 /* Set up the program header information for the dynamic linker
44c4e5d5
RM
1621 itself. It is needed in the dl_iterate_phdr callbacks. */
1622 const ElfW(Ehdr) *rtld_ehdr;
1623
1624 /* Starting from binutils-2.23, the linker will define the magic symbol
1625 __ehdr_start to point to our own ELF header if it is visible in a
1626 segment that also includes the phdrs. If that's not available, we use
1627 the old method that assumes the beginning of the file is part of the
1628 lowest-addressed PT_LOAD segment. */
1629#ifdef HAVE_EHDR_START
1630 extern const ElfW(Ehdr) __ehdr_start __attribute__ ((visibility ("hidden")));
1631 rtld_ehdr = &__ehdr_start;
1632#else
1633 rtld_ehdr = (void *) GL(dl_rtld_map).l_map_start;
1634#endif
1635 assert (rtld_ehdr->e_ehsize == sizeof *rtld_ehdr);
1636 assert (rtld_ehdr->e_phentsize == sizeof (ElfW(Phdr)));
1637
1638 const ElfW(Phdr) *rtld_phdr = (const void *) rtld_ehdr + rtld_ehdr->e_phoff;
1639
e8ed861d 1640 GL(dl_rtld_map).l_phdr = rtld_phdr;
553eca26
UD
1641 GL(dl_rtld_map).l_phnum = rtld_ehdr->e_phnum;
1642
9dcafc55 1643
e8ed861d
UD
1644 /* PT_GNU_RELRO is usually the last phdr. */
1645 size_t cnt = rtld_ehdr->e_phnum;
1646 while (cnt-- > 0)
1647 if (rtld_phdr[cnt].p_type == PT_GNU_RELRO)
1648 {
1649 GL(dl_rtld_map).l_relro_addr = rtld_phdr[cnt].p_vaddr;
1650 GL(dl_rtld_map).l_relro_size = rtld_phdr[cnt].p_memsz;
1651 break;
1652 }
1653
9dcafc55
UD
1654 /* Add the dynamic linker to the TLS list if it also uses TLS. */
1655 if (GL(dl_rtld_map).l_tls_blocksize != 0)
1656 /* Assign a module ID. Do this before loading any audit modules. */
1657 GL(dl_rtld_map).l_tls_modid = _dl_next_tls_modid ();
9dcafc55 1658
8f7a75d7
FW
1659 audit_list_add_dynamic_tag (&audit_list, main_map, DT_AUDIT);
1660 audit_list_add_dynamic_tag (&audit_list, main_map, DT_DEPAUDIT);
1661
9dcafc55 1662 /* If we have auditing DSOs to load, do it now. */
81b82fb9 1663 bool need_security_init = true;
4c6e0415 1664 if (audit_list.length > 0)
9dcafc55 1665 {
3abee0b7
UD
1666 /* Since we start using the auditing DSOs right away we need to
1667 initialize the data structures now. */
1668 tcbp = init_tls ();
1669
4c48ef06
UD
1670 /* Initialize security features. We need to do it this early
1671 since otherwise the constructors of the audit libraries will
1672 use different values (especially the pointer guard) and will
1673 fail later on. */
1674 security_init ();
81b82fb9 1675 need_security_init = false;
4c48ef06 1676
4c6e0415 1677 load_audit_modules (main_map, &audit_list);
9dcafc55
UD
1678 }
1679
d0503676
CD
1680 /* Keep track of the currently loaded modules to count how many
1681 non-audit modules which use TLS are loaded. */
1682 size_t count_modids = _dl_count_modids ();
1683
c63d8f80
UD
1684 /* Set up debugging before the debugger is notified for the first time. */
1685#ifdef ELF_MACHINE_DEBUG_SETUP
1686 /* Some machines (e.g. MIPS) don't use DT_DEBUG in this way. */
1687 ELF_MACHINE_DEBUG_SETUP (main_map, r);
1688 ELF_MACHINE_DEBUG_SETUP (&GL(dl_rtld_map), r);
1689#else
1690 if (main_map->l_info[DT_DEBUG] != NULL)
1691 /* There is a DT_DEBUG entry in the dynamic section. Fill it in
1692 with the run-time address of the r_debug structure */
1693 main_map->l_info[DT_DEBUG]->d_un.d_ptr = (ElfW(Addr)) r;
1694
1695 /* Fill in the pointer in the dynamic linker's own dynamic section, in
1696 case you run gdb on the dynamic linker directly. */
1697 if (GL(dl_rtld_map).l_info[DT_DEBUG] != NULL)
1698 GL(dl_rtld_map).l_info[DT_DEBUG]->d_un.d_ptr = (ElfW(Addr)) r;
1699#endif
1700
9dcafc55
UD
1701 /* We start adding objects. */
1702 r->r_state = RT_ADD;
1703 _dl_debug_state ();
815e6fa3 1704 LIBC_PROBE (init_start, 2, LM_ID_BASE, r);
9dcafc55
UD
1705
1706 /* Auditing checkpoint: we are ready to signal that the initial map
1707 is being constructed. */
a1ffb40e 1708 if (__glibc_unlikely (GLRO(dl_naudit) > 0))
9dcafc55
UD
1709 {
1710 struct audit_ifaces *afct = GLRO(dl_audit);
1711 for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt)
1712 {
1713 if (afct->activity != NULL)
e1d559f3
FW
1714 afct->activity (&link_map_audit_state (main_map, cnt)->cookie,
1715 LA_ACT_ADD);
9dcafc55
UD
1716
1717 afct = afct->next;
1718 }
1719 }
1720
14bab8de 1721 /* We have two ways to specify objects to preload: via environment
49c091e5 1722 variable and via the file /etc/ld.so.preload. The latter can also
14bab8de 1723 be used when security is enabled. */
ab1d521d 1724 assert (*first_preload == NULL);
20fe49b9
UD
1725 struct link_map **preloads = NULL;
1726 unsigned int npreloads = 0;
14bab8de 1727
a1ffb40e 1728 if (__glibc_unlikely (preloadlist != NULL))
c4029823 1729 {
1e372ded
AZ
1730 RTLD_TIMING_VAR (start);
1731 rtld_timer_start (&start);
8692ebdb 1732 npreloads += handle_preload_list (preloadlist, main_map, "LD_PRELOAD");
1e372ded 1733 rtld_timer_accum (&load_time, start);
8692ebdb
DN
1734 }
1735
1736 if (__glibc_unlikely (preloadarg != NULL))
1737 {
1e372ded
AZ
1738 RTLD_TIMING_VAR (start);
1739 rtld_timer_start (&start);
8692ebdb 1740 npreloads += handle_preload_list (preloadarg, main_map, "--preload");
1e372ded 1741 rtld_timer_accum (&load_time, start);
c4029823
UD
1742 }
1743
761490a1
UD
1744 /* There usually is no ld.so.preload file, it should only be used
1745 for emergencies and testing. So the open call etc should usually
1746 fail. Using access() on a non-existing file is faster than using
1747 open(). So we do this first. If it succeeds we do almost twice
1748 the work but this does not matter, since it is not for production
1749 use. */
1750 static const char preload_file[] = "/etc/ld.so.preload";
a1ffb40e 1751 if (__glibc_unlikely (__access (preload_file, R_OK) == 0))
14bab8de 1752 {
761490a1
UD
1753 /* Read the contents of the file. */
1754 file = _dl_sysdep_read_whole_file (preload_file, &file_size,
1755 PROT_READ | PROT_WRITE);
a1ffb40e 1756 if (__glibc_unlikely (file != MAP_FAILED))
14bab8de 1757 {
761490a1
UD
1758 /* Parse the file. It contains names of libraries to be loaded,
1759 separated by white spaces or `:'. It may also contain
1760 comments introduced by `#'. */
1761 char *problem;
1762 char *runp;
1763 size_t rest;
1764
1765 /* Eliminate comments. */
e2102c14 1766 runp = file;
761490a1
UD
1767 rest = file_size;
1768 while (rest > 0)
1769 {
1770 char *comment = memchr (runp, '#', rest);
1771 if (comment == NULL)
1772 break;
1773
1774 rest -= comment - runp;
1775 do
1776 *comment = ' ';
1777 while (--rest > 0 && *++comment != '\n');
1778 }
1779
1780 /* We have one problematic case: if we have a name at the end of
1781 the file without a trailing terminating characters, we cannot
1782 place the \0. Handle the case separately. */
1783 if (file[file_size - 1] != ' ' && file[file_size - 1] != '\t'
1784 && file[file_size - 1] != '\n' && file[file_size - 1] != ':')
1785 {
1786 problem = &file[file_size];
1787 while (problem > file && problem[-1] != ' '
1788 && problem[-1] != '\t'
1789 && problem[-1] != '\n' && problem[-1] != ':')
1790 --problem;
1791
1792 if (problem > file)
1793 problem[-1] = '\0';
1794 }
1795 else
1796 {
1797 problem = NULL;
1798 file[file_size - 1] = '\0';
1799 }
f04b9a68 1800
1e372ded
AZ
1801 RTLD_TIMING_VAR (start);
1802 rtld_timer_start (&start);
f04b9a68 1803
761490a1
UD
1804 if (file != problem)
1805 {
1806 char *p;
1807 runp = file;
1808 while ((p = strsep (&runp, ": \t\n")) != NULL)
1809 if (p[0] != '\0')
20fe49b9 1810 npreloads += do_preload (p, main_map, preload_file);
761490a1
UD
1811 }
1812
1813 if (problem != NULL)
1814 {
1815 char *p = strndupa (problem, file_size - (problem - file));
20fe49b9
UD
1816
1817 npreloads += do_preload (p, main_map, preload_file);
761490a1 1818 }
14bab8de 1819
1e372ded 1820 rtld_timer_accum (&load_time, start);
db276fa1 1821
761490a1
UD
1822 /* We don't need the file anymore. */
1823 __munmap (file, file_size);
1824 }
14bab8de
UD
1825 }
1826
a1ffb40e 1827 if (__glibc_unlikely (*first_preload != NULL))
14bab8de
UD
1828 {
1829 /* Set up PRELOADS with a vector of the preloaded libraries. */
ab1d521d 1830 struct link_map *l = *first_preload;
14bab8de 1831 preloads = __alloca (npreloads * sizeof preloads[0]);
14bab8de
UD
1832 i = 0;
1833 do
1834 {
1835 preloads[i++] = l;
1836 l = l->l_next;
1837 } while (l);
1838 assert (i == npreloads);
1839 }
1840
2064087b
RM
1841 /* Load all the libraries specified by DT_NEEDED entries. If LD_PRELOAD
1842 specified some libraries to load, these are inserted before the actual
1843 dependencies in the executable's searchlist for symbol resolution. */
1e372ded
AZ
1844 {
1845 RTLD_TIMING_VAR (start);
1846 rtld_timer_start (&start);
1847 _dl_map_object_deps (main_map, preloads, npreloads, mode == trace, 0);
1848 rtld_timer_accum (&load_time, start);
1849 }
e3e35cfc 1850
20fe49b9 1851 /* Mark all objects as being in the global scope. */
c0f62c56 1852 for (i = main_map->l_searchlist.r_nlist; i > 0; )
20fe49b9 1853 main_map->l_searchlist.r_list[--i]->l_global = 1;
d66e34cd 1854
f9496a7b 1855 /* Remove _dl_rtld_map from the chain. */
d6b5d570 1856 GL(dl_rtld_map).l_prev->l_next = GL(dl_rtld_map).l_next;
20fe49b9 1857 if (GL(dl_rtld_map).l_next != NULL)
d6b5d570 1858 GL(dl_rtld_map).l_next->l_prev = GL(dl_rtld_map).l_prev;
f9496a7b 1859
20fe49b9
UD
1860 for (i = 1; i < main_map->l_searchlist.r_nlist; ++i)
1861 if (main_map->l_searchlist.r_list[i] == &GL(dl_rtld_map))
1862 break;
1863
1864 bool rtld_multiple_ref = false;
a1ffb40e 1865 if (__glibc_likely (i < main_map->l_searchlist.r_nlist))
0200214b 1866 {
f9496a7b
RM
1867 /* Some DT_NEEDED entry referred to the interpreter object itself, so
1868 put it back in the list of visible objects. We insert it into the
1869 chain in symbol search order because gdb uses the chain's order as
1870 its symbol search order. */
20fe49b9
UD
1871 rtld_multiple_ref = true;
1872
c0f62c56 1873 GL(dl_rtld_map).l_prev = main_map->l_searchlist.r_list[i - 1];
b2bcd61a 1874 if (__builtin_expect (mode, normal) == normal)
3b3ddb4f 1875 {
c0f62c56
UD
1876 GL(dl_rtld_map).l_next = (i + 1 < main_map->l_searchlist.r_nlist
1877 ? main_map->l_searchlist.r_list[i + 1]
3b3ddb4f 1878 : NULL);
7775448e 1879#ifdef NEED_DL_SYSINFO_DSO
ab1d521d
RM
1880 if (GLRO(dl_sysinfo_map) != NULL
1881 && GL(dl_rtld_map).l_prev->l_next == GLRO(dl_sysinfo_map)
1882 && GL(dl_rtld_map).l_next != GLRO(dl_sysinfo_map))
1883 GL(dl_rtld_map).l_prev = GLRO(dl_sysinfo_map);
3b3ddb4f
UD
1884#endif
1885 }
b2bcd61a
UD
1886 else
1887 /* In trace mode there might be an invisible object (which we
1888 could not find) after the previous one in the search list.
1889 In this case it doesn't matter much where we put the
1890 interpreter object, so we just initialize the list pointer so
1891 that the assertion below holds. */
d6b5d570 1892 GL(dl_rtld_map).l_next = GL(dl_rtld_map).l_prev->l_next;
b2bcd61a 1893
d6b5d570
UD
1894 assert (GL(dl_rtld_map).l_prev->l_next == GL(dl_rtld_map).l_next);
1895 GL(dl_rtld_map).l_prev->l_next = &GL(dl_rtld_map);
3fb55878 1896 if (GL(dl_rtld_map).l_next != NULL)
f9496a7b 1897 {
d6b5d570
UD
1898 assert (GL(dl_rtld_map).l_next->l_prev == GL(dl_rtld_map).l_prev);
1899 GL(dl_rtld_map).l_next->l_prev = &GL(dl_rtld_map);
f9496a7b 1900 }
0200214b 1901 }
d66e34cd 1902
c84142e8
UD
1903 /* Now let us see whether all libraries are available in the
1904 versions we need. */
1905 {
993b3242
UD
1906 struct version_check_args args;
1907 args.doexit = mode == normal;
145b8413 1908 args.dotrace = mode == trace;
993b3242 1909 _dl_receive_error (print_missing_version, version_check_doit, &args);
c84142e8
UD
1910 }
1911
2d148689
RM
1912 /* We do not initialize any of the TLS functionality unless any of the
1913 initial modules uses TLS. This makes dynamic loading of modules with
1914 TLS impossible, but to support it requires either eagerly doing setup
1915 now or lazily doing it later. Doing it now makes us incompatible with
1916 an old kernel that can't perform TLS_INIT_TP, even if no TLS is ever
1917 used. Trying to do it lazily is too hairy to try when there could be
1918 multiple threads (from a non-TLS-using libpthread). */
9dcafc55 1919 bool was_tls_init_tp_called = tls_init_tp_called;
35f1e827 1920 if (tcbp == NULL)
9dcafc55 1921 tcbp = init_tls ();
0ecb606c 1922
81b82fb9 1923 if (__glibc_likely (need_security_init))
4c48ef06
UD
1924 /* Initialize security features. But only if we have not done it
1925 earlier. */
1926 security_init ();
827b7087 1927
9a821cf9 1928 if (__builtin_expect (mode, normal) != normal)
0200214b
RM
1929 {
1930 /* We were run just to list the shared libraries. It is
1931 important that we do this before real relocation, because the
1932 functions we call below for output may no longer work properly
1933 after relocation. */
81f3ac4c
UD
1934 struct link_map *l;
1935
afdca0f2 1936 if (GLRO(dl_debug_mask) & DL_DEBUG_PRELINK)
ceb2d9aa 1937 {
c0f62c56 1938 struct r_scope_elem *scope = &main_map->l_searchlist;
ceb2d9aa 1939
81f3ac4c 1940 for (i = 0; i < scope->r_nlist; i++)
32e6df36 1941 {
81f3ac4c
UD
1942 l = scope->r_list [i];
1943 if (l->l_faked)
32e6df36 1944 {
81f3ac4c
UD
1945 _dl_printf ("\t%s => not found\n", l->l_libname->name);
1946 continue;
1947 }
afdca0f2
UD
1948 if (_dl_name_match_p (GLRO(dl_trace_prelink), l))
1949 GLRO(dl_trace_prelink_map) = l;
81f3ac4c 1950 _dl_printf ("\t%s => %s (0x%0*Zx, 0x%0*Zx)",
b9375348
SP
1951 DSO_FILENAME (l->l_libname->name),
1952 DSO_FILENAME (l->l_name),
d347a4ab
UD
1953 (int) sizeof l->l_map_start * 2,
1954 (size_t) l->l_map_start,
1955 (int) sizeof l->l_addr * 2,
1956 (size_t) l->l_addr);
11bf311e 1957
81f3ac4c
UD
1958 if (l->l_tls_modid)
1959 _dl_printf (" TLS(0x%Zx, 0x%0*Zx)\n", l->l_tls_modid,
1960 (int) sizeof l->l_tls_offset * 2,
d347a4ab 1961 (size_t) l->l_tls_offset);
81f3ac4c 1962 else
81f3ac4c 1963 _dl_printf ("\n");
32e6df36 1964 }
ceb2d9aa 1965 }
7a11603d
UD
1966 else if (GLRO(dl_debug_mask) & DL_DEBUG_UNUSED)
1967 {
1968 /* Look through the dependencies of the main executable
1969 and determine which of them is not actually
1970 required. */
c0f62c56 1971 struct link_map *l = main_map;
7a11603d
UD
1972
1973 /* Relocate the main executable. */
2ca285b0 1974 struct relocate_args args = { .l = l,
3a62d00d
AS
1975 .reloc_mode = ((GLRO(dl_lazy)
1976 ? RTLD_LAZY : 0)
1977 | __RTLD_NOIFUNC) };
7a11603d
UD
1978 _dl_receive_error (print_unresolved, relocate_doit, &args);
1979
1980 /* This loop depends on the dependencies of the executable to
1981 correspond in number and order to the DT_NEEDED entries. */
c0f62c56 1982 ElfW(Dyn) *dyn = main_map->l_ld;
7a11603d
UD
1983 bool first = true;
1984 while (dyn->d_tag != DT_NULL)
1985 {
1986 if (dyn->d_tag == DT_NEEDED)
1987 {
1988 l = l->l_next;
7775448e 1989#ifdef NEED_DL_SYSINFO_DSO
ff9f1c5f
DM
1990 /* Skip the VDSO since it's not part of the list
1991 of objects we brought in via DT_NEEDED entries. */
1992 if (l == GLRO(dl_sysinfo_map))
1993 l = l->l_next;
1994#endif
7a11603d
UD
1995 if (!l->l_used)
1996 {
1997 if (first)
1998 {
1999 _dl_printf ("Unused direct dependencies:\n");
2000 first = false;
2001 }
2002
2003 _dl_printf ("\t%s\n", l->l_name);
2004 }
2005 }
2006
2007 ++dyn;
2008 }
2009
2010 _exit (first != true);
2011 }
c0f62c56 2012 else if (! main_map->l_info[DT_NEEDED])
81f3ac4c
UD
2013 _dl_printf ("\tstatically linked\n");
2014 else
2015 {
c0f62c56 2016 for (l = main_map->l_next; l; l = l->l_next)
81f3ac4c
UD
2017 if (l->l_faked)
2018 /* The library was not found. */
2019 _dl_printf ("\t%s => not found\n", l->l_libname->name);
75489693 2020 else if (strcmp (l->l_libname->name, l->l_name) == 0)
7a11603d
UD
2021 _dl_printf ("\t%s (0x%0*Zx)\n", l->l_libname->name,
2022 (int) sizeof l->l_map_start * 2,
2023 (size_t) l->l_map_start);
81f3ac4c
UD
2024 else
2025 _dl_printf ("\t%s => %s (0x%0*Zx)\n", l->l_libname->name,
2026 l->l_name, (int) sizeof l->l_map_start * 2,
d347a4ab 2027 (size_t) l->l_map_start);
81f3ac4c 2028 }
1a3a58fd 2029
9a821cf9 2030 if (__builtin_expect (mode, trace) != trace)
5a47e7f2 2031 for (i = 1; i < (unsigned int) _dl_argc; ++i)
cddcfecf
RM
2032 {
2033 const ElfW(Sym) *ref = NULL;
c0282c06
UD
2034 ElfW(Addr) loadbase;
2035 lookup_t result;
c0282c06 2036
4243cbea 2037 result = _dl_lookup_symbol_x (_dl_argv[i], main_map,
11bf311e
UD
2038 &ref, main_map->l_scope,
2039 NULL, ELF_RTYPE_CLASS_PLT,
021723ab 2040 DL_LOOKUP_ADD_DEPENDENCY, NULL);
c0282c06 2041
10a446dd 2042 loadbase = LOOKUP_VALUE_ADDRESS (result, false);
c0282c06 2043
35fc382a 2044 _dl_printf ("%s found at 0x%0*Zd in object at 0x%0*Zd\n",
4243cbea 2045 _dl_argv[i],
d347a4ab
UD
2046 (int) sizeof ref->st_value * 2,
2047 (size_t) ref->st_value,
2048 (int) sizeof loadbase * 2, (size_t) loadbase);
cddcfecf 2049 }
ce37fa88 2050 else
fd26970f 2051 {
20fe49b9 2052 /* If LD_WARN is set, warn about undefined symbols. */
afdca0f2 2053 if (GLRO(dl_lazy) >= 0 && GLRO(dl_verbose))
ce37fa88
UD
2054 {
2055 /* We have to do symbol dependency testing. */
2056 struct relocate_args args;
48b67d71 2057 unsigned int i;
993b3242 2058
3a62d00d
AS
2059 args.reloc_mode = ((GLRO(dl_lazy) ? RTLD_LAZY : 0)
2060 | __RTLD_NOIFUNC);
fd26970f 2061
48b67d71
AS
2062 i = main_map->l_searchlist.r_nlist;
2063 while (i-- > 0)
ce37fa88 2064 {
48b67d71 2065 struct link_map *l = main_map->l_initfini[i];
d6b5d570 2066 if (l != &GL(dl_rtld_map) && ! l->l_faked)
ce37fa88
UD
2067 {
2068 args.l = l;
2069 _dl_receive_error (print_unresolved, relocate_doit,
2070 &args);
ce37fa88 2071 }
20fe49b9 2072 }
32e6df36 2073
afdca0f2 2074 if ((GLRO(dl_debug_mask) & DL_DEBUG_PRELINK)
20fe49b9 2075 && rtld_multiple_ref)
e38c954b
UD
2076 {
2077 /* Mark the link map as not yet relocated again. */
2078 GL(dl_rtld_map).l_relocated = 0;
11bf311e 2079 _dl_relocate_object (&GL(dl_rtld_map),
3a62d00d 2080 main_map->l_scope, __RTLD_NOIFUNC, 0);
e38c954b 2081 }
3a56ea26 2082 }
b0982c4a 2083#define VERNEEDTAG (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGIDX (DT_VERNEED))
120b4c49 2084 if (version_info)
fd26970f 2085 {
ce37fa88
UD
2086 /* Print more information. This means here, print information
2087 about the versions needed. */
2088 int first = 1;
c0f62c56 2089 struct link_map *map;
ce37fa88 2090
c0f62c56 2091 for (map = main_map; map != NULL; map = map->l_next)
fd26970f 2092 {
f41c8091 2093 const char *strtab;
ce37fa88 2094 ElfW(Dyn) *dyn = map->l_info[VERNEEDTAG];
f41c8091
UD
2095 ElfW(Verneed) *ent;
2096
2097 if (dyn == NULL)
2098 continue;
2099
a42195db 2100 strtab = (const void *) D_PTR (map, l_info[DT_STRTAB]);
f41c8091 2101 ent = (ElfW(Verneed) *) (map->l_addr + dyn->d_un.d_ptr);
ce37fa88 2102
f41c8091 2103 if (first)
ce37fa88 2104 {
35fc382a 2105 _dl_printf ("\n\tVersion information:\n");
f41c8091
UD
2106 first = 0;
2107 }
ce37fa88 2108
b9375348 2109 _dl_printf ("\t%s:\n", DSO_FILENAME (map->l_name));
f41c8091
UD
2110
2111 while (1)
2112 {
2113 ElfW(Vernaux) *aux;
2114 struct link_map *needed;
ce37fa88 2115
f41c8091
UD
2116 needed = find_needed (strtab + ent->vn_file);
2117 aux = (ElfW(Vernaux) *) ((char *) ent + ent->vn_aux);
ce37fa88
UD
2118
2119 while (1)
2120 {
f41c8091
UD
2121 const char *fname = NULL;
2122
f41c8091 2123 if (needed != NULL
ba9fcb3f
UD
2124 && match_version (strtab + aux->vna_name,
2125 needed))
f41c8091
UD
2126 fname = needed->l_name;
2127
35fc382a
UD
2128 _dl_printf ("\t\t%s (%s) %s=> %s\n",
2129 strtab + ent->vn_file,
2130 strtab + aux->vna_name,
2131 aux->vna_flags & VER_FLG_WEAK
2132 ? "[WEAK] " : "",
2133 fname ?: "not found");
ce37fa88 2134
f41c8091
UD
2135 if (aux->vna_next == 0)
2136 /* No more symbols. */
ce37fa88
UD
2137 break;
2138
f41c8091
UD
2139 /* Next symbol. */
2140 aux = (ElfW(Vernaux) *) ((char *) aux
2141 + aux->vna_next);
ce37fa88 2142 }
f41c8091
UD
2143
2144 if (ent->vn_next == 0)
2145 /* No more dependencies. */
2146 break;
2147
2148 /* Next dependency. */
2149 ent = (ElfW(Verneed) *) ((char *) ent + ent->vn_next);
ce37fa88 2150 }
fd26970f 2151 }
ce37fa88 2152 }
fd26970f 2153 }
d66e34cd 2154
0200214b
RM
2155 _exit (0);
2156 }
86d2c878 2157
c0f62c56 2158 if (main_map->l_info[ADDRIDX (DT_GNU_LIBLIST)]
768027a4
UD
2159 && ! __builtin_expect (GLRO(dl_profile) != NULL, 0)
2160 && ! __builtin_expect (GLRO(dl_dynamic_weak), 0))
32e6df36
UD
2161 {
2162 ElfW(Lib) *liblist, *liblistend;
2163 struct link_map **r_list, **r_listend, *l;
c0f62c56 2164 const char *strtab = (const void *) D_PTR (main_map, l_info[DT_STRTAB]);
32e6df36 2165
c0f62c56 2166 assert (main_map->l_info[VALIDX (DT_GNU_LIBLISTSZ)] != NULL);
32e6df36 2167 liblist = (ElfW(Lib) *)
c0f62c56 2168 main_map->l_info[ADDRIDX (DT_GNU_LIBLIST)]->d_un.d_ptr;
32e6df36 2169 liblistend = (ElfW(Lib) *)
34a5a146
JM
2170 ((char *) liblist
2171 + main_map->l_info[VALIDX (DT_GNU_LIBLISTSZ)]->d_un.d_val);
c0f62c56
UD
2172 r_list = main_map->l_searchlist.r_list;
2173 r_listend = r_list + main_map->l_searchlist.r_nlist;
32e6df36
UD
2174
2175 for (; r_list < r_listend && liblist < liblistend; r_list++)
2176 {
2177 l = *r_list;
2178
c0f62c56 2179 if (l == main_map)
32e6df36
UD
2180 continue;
2181
2182 /* If the library is not mapped where it should, fail. */
2183 if (l->l_addr)
2184 break;
2185
2186 /* Next, check if checksum matches. */
2187 if (l->l_info [VALIDX(DT_CHECKSUM)] == NULL
2188 || l->l_info [VALIDX(DT_CHECKSUM)]->d_un.d_val
2189 != liblist->l_checksum)
2190 break;
2191
2192 if (l->l_info [VALIDX(DT_GNU_PRELINKED)] == NULL
2193 || l->l_info [VALIDX(DT_GNU_PRELINKED)]->d_un.d_val
2194 != liblist->l_time_stamp)
2195 break;
2196
2197 if (! _dl_name_match_p (strtab + liblist->l_name, l))
2198 break;
2199
2200 ++liblist;
2201 }
2202
2203
2204 if (r_list == r_listend && liblist == liblistend)
164a7164 2205 prelinked = true;
32e6df36 2206
a1ffb40e 2207 if (__glibc_unlikely (GLRO(dl_debug_mask) & DL_DEBUG_LIBS))
b85a0f39
UD
2208 _dl_debug_printf ("\nprelink checking: %s\n",
2209 prelinked ? "ok" : "failed");
32e6df36
UD
2210 }
2211
ed20b3d9 2212
c31e278f 2213 /* Now set up the variable which helps the assembler startup code. */
c0f62c56 2214 GL(dl_ns)[LM_ID_BASE]._ns_main_searchlist = &main_map->l_searchlist;
c31e278f
UD
2215
2216 /* Save the information about the original global scope list since
2217 we need it in the memory handling later. */
c0f62c56 2218 GLRO(dl_initial_searchlist) = *GL(dl_ns)[LM_ID_BASE]._ns_main_searchlist;
c31e278f 2219
e23fe25b 2220 /* Remember the last search directory added at startup, now that
8e1472d2
FW
2221 malloc will no longer be the one from dl-minimal.c. As a side
2222 effect, this marks ld.so as initialized, so that the rtld_active
2223 function returns true from now on. */
e23fe25b
AS
2224 GLRO(dl_init_all_dirs) = GL(dl_all_dirs);
2225
73d7af4f 2226 /* Print scope information. */
a1ffb40e 2227 if (__glibc_unlikely (GLRO(dl_debug_mask) & DL_DEBUG_SCOPES))
73d7af4f
UD
2228 {
2229 _dl_debug_printf ("\nInitial object scopes\n");
2230
2231 for (struct link_map *l = main_map; l != NULL; l = l->l_next)
174baab3 2232 _dl_show_scope (l, 0);
73d7af4f
UD
2233 }
2234
f753fa7d
L
2235 _rtld_main_check (main_map, _dl_argv[0]);
2236
32e6df36
UD
2237 if (prelinked)
2238 {
c0f62c56 2239 if (main_map->l_info [ADDRIDX (DT_GNU_CONFLICT)] != NULL)
32e6df36
UD
2240 {
2241 ElfW(Rela) *conflict, *conflictend;
32e6df36 2242
1e372ded
AZ
2243 RTLD_TIMING_VAR (start);
2244 rtld_timer_start (&start);
2245
c0f62c56 2246 assert (main_map->l_info [VALIDX (DT_GNU_CONFLICTSZ)] != NULL);
32e6df36 2247 conflict = (ElfW(Rela) *)
c0f62c56 2248 main_map->l_info [ADDRIDX (DT_GNU_CONFLICT)]->d_un.d_ptr;
32e6df36 2249 conflictend = (ElfW(Rela) *)
d89ae1d5 2250 ((char *) conflict
c0f62c56
UD
2251 + main_map->l_info [VALIDX (DT_GNU_CONFLICTSZ)]->d_un.d_val);
2252 _dl_resolve_conflicts (main_map, conflict, conflictend);
1e372ded
AZ
2253
2254 rtld_timer_stop (&relocate_time, start);
32e6df36
UD
2255 }
2256
3a0ecccb
FW
2257 /* The library defining malloc has already been relocated due to
2258 prelinking. Resolve the malloc symbols for the dynamic
2259 loader. */
2260 __rtld_malloc_init_real (main_map);
d89ae1d5
RM
2261
2262 /* Mark all the objects so we know they have been already relocated. */
9dcafc55 2263 for (struct link_map *l = main_map; l != NULL; l = l->l_next)
e8648a5a
UD
2264 {
2265 l->l_relocated = 1;
2266 if (l->l_relro_size)
2267 _dl_protect_relro (l);
9dcafc55
UD
2268
2269 /* Add object to slot information data if necessasy. */
2270 if (l->l_tls_blocksize != 0 && tls_init_tp_called)
a509eb11 2271 _dl_add_to_slotinfo (l, true);
e8648a5a 2272 }
32e6df36
UD
2273 }
2274 else
164a7164
UD
2275 {
2276 /* Now we have all the objects loaded. Relocate them all except for
2277 the dynamic linker itself. We do this in reverse order so that copy
2278 relocs of earlier objects overwrite the data written by later
2279 objects. We do not re-relocate the dynamic linker itself in this
2280 loop because that could result in the GOT entries for functions we
2281 call being changed, and that would break us. It is safe to relocate
2282 the dynamic linker out of order because it has no copy relocs (we
2283 know that because it is self-contained). */
2284
afdca0f2 2285 int consider_profiling = GLRO(dl_profile) != NULL;
c0fb8a56 2286
164a7164 2287 /* If we are profiling we also must do lazy reloaction. */
afdca0f2 2288 GLRO(dl_lazy) |= consider_profiling;
c0fb8a56 2289
1e372ded
AZ
2290 RTLD_TIMING_VAR (start);
2291 rtld_timer_start (&start);
2bc17433
AS
2292 unsigned i = main_map->l_searchlist.r_nlist;
2293 while (i-- > 0)
164a7164 2294 {
2bc17433
AS
2295 struct link_map *l = main_map->l_initfini[i];
2296
164a7164
UD
2297 /* While we are at it, help the memory handling a bit. We have to
2298 mark some data structures as allocated with the fake malloc()
2299 implementation in ld.so. */
2300 struct libname_list *lnp = l->l_libname->next;
752a2a50 2301
164a7164
UD
2302 while (__builtin_expect (lnp != NULL, 0))
2303 {
2304 lnp->dont_free = 1;
2305 lnp = lnp->next;
2306 }
0479b305
AS
2307 /* Also allocated with the fake malloc(). */
2308 l->l_free_initfini = 0;
752a2a50 2309
164a7164 2310 if (l != &GL(dl_rtld_map))
2ca285b0 2311 _dl_relocate_object (l, l->l_scope, GLRO(dl_lazy) ? RTLD_LAZY : 0,
154d10bd 2312 consider_profiling);
be935610 2313
9dcafc55
UD
2314 /* Add object to slot information data if necessasy. */
2315 if (l->l_tls_blocksize != 0 && tls_init_tp_called)
a509eb11 2316 _dl_add_to_slotinfo (l, true);
164a7164 2317 }
1e372ded 2318 rtld_timer_stop (&relocate_time, start);
164a7164 2319
164a7164
UD
2320 /* Now enable profiling if needed. Like the previous call,
2321 this has to go here because the calls it makes should use the
2322 rtld versions of the functions (particularly calloc()), but it
2323 needs to have _dl_profile_map set up by the relocator. */
a1ffb40e 2324 if (__glibc_unlikely (GL(dl_profile_map) != NULL))
164a7164 2325 /* We must prepare the profiling. */
53bfdc1c 2326 _dl_start_profile ();
164a7164 2327 }
ac16e905 2328
d0503676
CD
2329 if ((!was_tls_init_tp_called && GL(dl_tls_max_dtv_idx) > 0)
2330 || count_modids != _dl_count_modids ())
35f1e827 2331 ++GL(dl_tls_generation);
9dcafc55 2332
35f1e827
UD
2333 /* Now that we have completed relocation, the initializer data
2334 for the TLS blocks has its final values and we can copy them
91ac3a7d
TMQMF
2335 into the main thread's TLS area, which we allocated above.
2336 Note: thread-local variables must only be accessed after completing
2337 the next step. */
35f1e827 2338 _dl_allocate_tls_init (tcbp);
a334319f 2339
3d8c8bff 2340 /* And finally install it for the main thread. */
35f1e827
UD
2341 if (! tls_init_tp_called)
2342 {
774f9285 2343 const char *lossage = TLS_INIT_TP (tcbp);
a1ffb40e 2344 if (__glibc_unlikely (lossage != NULL))
35f1e827
UD
2345 _dl_fatal_printf ("cannot set up thread-local storage: %s\n",
2346 lossage);
0ecb606c 2347 }
0ecb606c 2348
e23fe25b
AS
2349 /* Make sure no new search directories have been added. */
2350 assert (GLRO(dl_init_all_dirs) == GL(dl_all_dirs));
bc5fb037 2351
cafdfdb6
RM
2352 if (! prelinked && rtld_multiple_ref)
2353 {
2354 /* There was an explicit ref to the dynamic linker as a shared lib.
2355 Re-relocate ourselves with user-controlled symbol definitions.
2356
2357 We must do this after TLS initialization in case after this
2358 re-relocation, we might call a user-supplied function
2359 (e.g. calloc from _dl_relocate_object) that uses TLS data. */
2360
3a0ecccb
FW
2361 /* The malloc implementation has been relocated, so resolving
2362 its symbols (and potentially calling IFUNC resolvers) is safe
2363 at this point. */
2364 __rtld_malloc_init_real (main_map);
2365
1e372ded
AZ
2366 RTLD_TIMING_VAR (start);
2367 rtld_timer_start (&start);
cafdfdb6 2368
cafdfdb6
RM
2369 /* Mark the link map as not yet relocated again. */
2370 GL(dl_rtld_map).l_relocated = 0;
c0a777e8 2371 _dl_relocate_object (&GL(dl_rtld_map), main_map->l_scope, 0, 0);
1e372ded
AZ
2372
2373 rtld_timer_accum (&relocate_time, start);
cafdfdb6
RM
2374 }
2375
ec935dea
FW
2376 /* Relocation is complete. Perform early libc initialization. */
2377 _dl_call_libc_early_init (GL(dl_ns)[LM_ID_BASE].libc_map);
2378
bf8523c8
RM
2379 /* Do any necessary cleanups for the startup OS interface code.
2380 We do these now so that no calls are made after rtld re-relocation
2381 which might be resolved to different functions than we expect.
2382 We cannot do this before relocating the other objects because
2383 _dl_relocate_object might need to call `mprotect' for DT_TEXTREL. */
2384 _dl_sysdep_start_cleanup ();
2385
9dcafc55
UD
2386#ifdef SHARED
2387 /* Auditing checkpoint: we have added all objects. */
a1ffb40e 2388 if (__glibc_unlikely (GLRO(dl_naudit) > 0))
9dcafc55
UD
2389 {
2390 struct link_map *head = GL(dl_ns)[LM_ID_BASE]._ns_loaded;
2391 /* Do not call the functions for any auditing object. */
2392 if (head->l_auditing == 0)
2393 {
2394 struct audit_ifaces *afct = GLRO(dl_audit);
2395 for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt)
2396 {
2397 if (afct->activity != NULL)
e1d559f3
FW
2398 afct->activity (&link_map_audit_state (head, cnt)->cookie,
2399 LA_ACT_CONSISTENT);
9dcafc55
UD
2400
2401 afct = afct->next;
2402 }
2403 }
2404 }
2405#endif
2406
2407 /* Notify the debugger all new objects are now ready to go. We must re-get
2408 the address since by now the variable might be in another object. */
29f97654 2409 r = _dl_debug_initialize (0, LM_ID_BASE);
9dcafc55 2410 r->r_state = RT_CONSISTENT;
154d10bd 2411 _dl_debug_state ();
815e6fa3 2412 LIBC_PROBE (init_complete, 2, LM_ID_BASE, r);
0200214b 2413
f57f8055 2414#if defined USE_LDCONFIG && !defined MAP_COPY
08cac4ac 2415 /* We must munmap() the cache file. */
154d10bd 2416 _dl_unload_cache ();
08cac4ac
UD
2417#endif
2418
d66e34cd
RM
2419 /* Once we return, _dl_sysdep_start will invoke
2420 the DT_INIT functions and then *USER_ENTRY. */
2421}
fd26970f
UD
2422\f
2423/* This is a little helper function for resolving symbols while
2424 tracing the binary. */
2425static void
c84142e8
UD
2426print_unresolved (int errcode __attribute__ ((unused)), const char *objname,
2427 const char *errstring)
fd26970f 2428{
3996f34b 2429 if (objname[0] == '\0')
b9375348 2430 objname = RTLD_PROGNAME;
35fc382a 2431 _dl_error_printf ("%s (%s)\n", errstring, objname);
fd26970f 2432}
c84142e8
UD
2433\f
2434/* This is a little helper function for resolving symbols while
2435 tracing the binary. */
2436static void
2437print_missing_version (int errcode __attribute__ ((unused)),
2438 const char *objname, const char *errstring)
2439{
b9375348 2440 _dl_error_printf ("%s: %s: %s\n", RTLD_PROGNAME,
35fc382a 2441 objname, errstring);
c84142e8 2442}
ea278354 2443\f
7dea968e 2444/* Nonzero if any of the debugging options is enabled. */
392a6b52 2445static int any_debug attribute_relro;
7dea968e 2446
b5efde2f
UD
2447/* Process the string given as the parameter which explains which debugging
2448 options are enabled. */
2449static void
14c44e2e 2450process_dl_debug (const char *dl_debug)
b5efde2f 2451{
3e2040c8
UD
2452 /* When adding new entries make sure that the maximal length of a name
2453 is correctly handled in the LD_DEBUG_HELP code below. */
2454 static const struct
2455 {
379d4ec4
UD
2456 unsigned char len;
2457 const char name[10];
3e2040c8
UD
2458 const char helptext[41];
2459 unsigned short int mask;
2460 } debopts[] =
2461 {
379d4ec4
UD
2462#define LEN_AND_STR(str) sizeof (str) - 1, str
2463 { LEN_AND_STR ("libs"), "display library search paths",
3e2040c8 2464 DL_DEBUG_LIBS | DL_DEBUG_IMPCALLS },
379d4ec4 2465 { LEN_AND_STR ("reloc"), "display relocation processing",
3e2040c8 2466 DL_DEBUG_RELOC | DL_DEBUG_IMPCALLS },
379d4ec4 2467 { LEN_AND_STR ("files"), "display progress for input file",
3e2040c8 2468 DL_DEBUG_FILES | DL_DEBUG_IMPCALLS },
379d4ec4 2469 { LEN_AND_STR ("symbols"), "display symbol table processing",
3e2040c8 2470 DL_DEBUG_SYMBOLS | DL_DEBUG_IMPCALLS },
379d4ec4 2471 { LEN_AND_STR ("bindings"), "display information about symbol binding",
3e2040c8 2472 DL_DEBUG_BINDINGS | DL_DEBUG_IMPCALLS },
379d4ec4 2473 { LEN_AND_STR ("versions"), "display version dependencies",
3e2040c8 2474 DL_DEBUG_VERSIONS | DL_DEBUG_IMPCALLS },
73d7af4f
UD
2475 { LEN_AND_STR ("scopes"), "display scope information",
2476 DL_DEBUG_SCOPES },
379d4ec4 2477 { LEN_AND_STR ("all"), "all previous options combined",
3e2040c8 2478 DL_DEBUG_LIBS | DL_DEBUG_RELOC | DL_DEBUG_FILES | DL_DEBUG_SYMBOLS
73d7af4f
UD
2479 | DL_DEBUG_BINDINGS | DL_DEBUG_VERSIONS | DL_DEBUG_IMPCALLS
2480 | DL_DEBUG_SCOPES },
379d4ec4 2481 { LEN_AND_STR ("statistics"), "display relocation statistics",
3e2040c8 2482 DL_DEBUG_STATISTICS },
7a11603d
UD
2483 { LEN_AND_STR ("unused"), "determined unused DSOs",
2484 DL_DEBUG_UNUSED },
379d4ec4 2485 { LEN_AND_STR ("help"), "display this help message and exit",
3e2040c8
UD
2486 DL_DEBUG_HELP },
2487 };
2488#define ndebopts (sizeof (debopts) / sizeof (debopts[0]))
3e2040c8 2489
379d4ec4
UD
2490 /* Skip separating white spaces and commas. */
2491 while (*dl_debug != '\0')
b5efde2f 2492 {
379d4ec4 2493 if (*dl_debug != ' ' && *dl_debug != ',' && *dl_debug != ':')
b5efde2f 2494 {
3e2040c8 2495 size_t cnt;
379d4ec4 2496 size_t len = 1;
77aba05b 2497
379d4ec4
UD
2498 while (dl_debug[len] != '\0' && dl_debug[len] != ' '
2499 && dl_debug[len] != ',' && dl_debug[len] != ':')
2500 ++len;
14c44e2e 2501
3e2040c8 2502 for (cnt = 0; cnt < ndebopts; ++cnt)
379d4ec4
UD
2503 if (debopts[cnt].len == len
2504 && memcmp (dl_debug, debopts[cnt].name, len) == 0)
3e2040c8 2505 {
afdca0f2 2506 GLRO(dl_debug_mask) |= debopts[cnt].mask;
5688da55 2507 any_debug = 1;
3e2040c8
UD
2508 break;
2509 }
77aba05b 2510
3e2040c8
UD
2511 if (cnt == ndebopts)
2512 {
2513 /* Display a warning and skip everything until next
2514 separator. */
2515 char *copy = strndupa (dl_debug, len);
2516 _dl_error_printf ("\
2517warning: debug option `%s' unknown; try LD_DEBUG=help\n", copy);
379d4ec4
UD
2518 }
2519
2520 dl_debug += len;
2521 continue;
3e2040c8 2522 }
379d4ec4
UD
2523
2524 ++dl_debug;
3e2040c8 2525 }
77aba05b 2526
ff9f1c5f
DM
2527 if (GLRO(dl_debug_mask) & DL_DEBUG_UNUSED)
2528 {
2529 /* In order to get an accurate picture of whether a particular
2530 DT_NEEDED entry is actually used we have to process both
2531 the PLT and non-PLT relocation entries. */
2532 GLRO(dl_lazy) = 0;
2533 }
2534
afdca0f2 2535 if (GLRO(dl_debug_mask) & DL_DEBUG_HELP)
3e2040c8
UD
2536 {
2537 size_t cnt;
14c44e2e 2538
3e2040c8
UD
2539 _dl_printf ("\
2540Valid options for the LD_DEBUG environment variable are:\n\n");
db276fa1 2541
3e2040c8 2542 for (cnt = 0; cnt < ndebopts; ++cnt)
37d8b778
UD
2543 _dl_printf (" %.*s%s%s\n", debopts[cnt].len, debopts[cnt].name,
2544 " " + debopts[cnt].len - 3,
3e2040c8 2545 debopts[cnt].helptext);
14c44e2e 2546
3e2040c8
UD
2547 _dl_printf ("\n\
2548To direct the debugging output into a file instead of standard output\n\
2549a filename can be specified using the LD_DEBUG_OUTPUT environment variable.\n");
2550 _exit (0);
b5efde2f 2551 }
b5efde2f
UD
2552}
2553\f
ea278354
UD
2554/* Process all environments variables the dynamic linker must recognize.
2555 Since all of them start with `LD_' we are a bit smarter while finding
2556 all the entries. */
9360906d 2557extern char **_environ attribute_hidden;
67c94753 2558
d6b5d570 2559
ea278354 2560static void
4c6e0415 2561process_envvars (enum mode *modep, struct audit_list *audit_list)
ea278354 2562{
67c94753 2563 char **runp = _environ;
ea278354
UD
2564 char *envline;
2565 enum mode mode = normal;
7dea968e 2566 char *debug_output = NULL;
ea278354
UD
2567
2568 /* This is the default place for profiling data file. */
afdca0f2 2569 GLRO(dl_profile_output)
6bc6bd3b 2570 = &"/var/tmp\0/var/profile"[__libc_enable_secure ? 9 : 0];
ea278354
UD
2571
2572 while ((envline = _dl_next_ld_env_entry (&runp)) != NULL)
2573 {
379d4ec4
UD
2574 size_t len = 0;
2575
2576 while (envline[len] != '\0' && envline[len] != '=')
2577 ++len;
ea278354 2578
75e8d1f5
UD
2579 if (envline[len] != '=')
2580 /* This is a "LD_" variable at the end of the string without
2581 a '=' character. Ignore it since otherwise we will access
2582 invalid memory below. */
67c94753 2583 continue;
75e8d1f5 2584
67c94753 2585 switch (len)
ea278354 2586 {
14c44e2e
UD
2587 case 4:
2588 /* Warning level, verbose or not. */
67c94753 2589 if (memcmp (envline, "WARN", 4) == 0)
afdca0f2 2590 GLRO(dl_verbose) = envline[5] != '\0';
14c44e2e 2591 break;
ea278354 2592
14c44e2e
UD
2593 case 5:
2594 /* Debugging of the dynamic linker? */
67c94753 2595 if (memcmp (envline, "DEBUG", 5) == 0)
9dcafc55
UD
2596 {
2597 process_dl_debug (&envline[6]);
2598 break;
2599 }
2600 if (memcmp (envline, "AUDIT", 5) == 0)
4c6e0415 2601 audit_list_add_string (audit_list, &envline[6]);
14c44e2e 2602 break;
b5efde2f 2603
14c44e2e
UD
2604 case 7:
2605 /* Print information about versions. */
67c94753 2606 if (memcmp (envline, "VERBOSE", 7) == 0)
14c44e2e 2607 {
67c94753 2608 version_info = envline[8] != '\0';
14c44e2e
UD
2609 break;
2610 }
7dea968e 2611
14c44e2e 2612 /* List of objects to be preloaded. */
67c94753 2613 if (memcmp (envline, "PRELOAD", 7) == 0)
14c44e2e 2614 {
67c94753 2615 preloadlist = &envline[8];
14c44e2e
UD
2616 break;
2617 }
120b4c49 2618
14c44e2e 2619 /* Which shared object shall be profiled. */
c95f3fd4 2620 if (memcmp (envline, "PROFILE", 7) == 0 && envline[8] != '\0')
afdca0f2 2621 GLRO(dl_profile) = &envline[8];
14c44e2e 2622 break;
120b4c49 2623
14c44e2e
UD
2624 case 8:
2625 /* Do we bind early? */
67c94753 2626 if (memcmp (envline, "BIND_NOW", 8) == 0)
f53c03c2 2627 {
afdca0f2 2628 GLRO(dl_lazy) = envline[9] == '\0';
f53c03c2
UD
2629 break;
2630 }
67c94753 2631 if (memcmp (envline, "BIND_NOT", 8) == 0)
afdca0f2 2632 GLRO(dl_bind_not) = envline[9] != '\0';
14c44e2e 2633 break;
ea278354 2634
14c44e2e
UD
2635 case 9:
2636 /* Test whether we want to see the content of the auxiliary
2637 array passed up from the kernel. */
6bc6bd3b 2638 if (!__libc_enable_secure
00a12162 2639 && memcmp (envline, "SHOW_AUXV", 9) == 0)
14c44e2e
UD
2640 _dl_show_auxv ();
2641 break;
ea278354 2642
ff08fc59 2643#if !HAVE_TUNABLES
12264bd7 2644 case 10:
3081378b 2645 /* Mask for the important hardware capabilities. */
1c1243b6
SP
2646 if (!__libc_enable_secure
2647 && memcmp (envline, "HWCAP_MASK", 10) == 0)
37b66c0b 2648 GLRO(dl_hwcap_mask) = _dl_strtoul (&envline[11], NULL);
12264bd7 2649 break;
ff08fc59 2650#endif
12264bd7 2651
f787edde
UD
2652 case 11:
2653 /* Path where the binary is found. */
6bc6bd3b 2654 if (!__libc_enable_secure
67c94753 2655 && memcmp (envline, "ORIGIN_PATH", 11) == 0)
afdca0f2 2656 GLRO(dl_origin_path) = &envline[12];
f787edde
UD
2657 break;
2658
14c44e2e 2659 case 12:
dec126b4 2660 /* The library search path. */
f6110a8f
FW
2661 if (!__libc_enable_secure
2662 && memcmp (envline, "LIBRARY_PATH", 12) == 0)
dec126b4 2663 {
67c94753 2664 library_path = &envline[13];
dec126b4
UD
2665 break;
2666 }
2667
14c44e2e 2668 /* Where to place the profiling data file. */
67c94753 2669 if (memcmp (envline, "DEBUG_OUTPUT", 12) == 0)
14c44e2e 2670 {
67c94753 2671 debug_output = &envline[13];
14c44e2e
UD
2672 break;
2673 }
ea278354 2674
6bc6bd3b 2675 if (!__libc_enable_secure
00a12162 2676 && memcmp (envline, "DYNAMIC_WEAK", 12) == 0)
afdca0f2 2677 GLRO(dl_dynamic_weak) = 1;
14c44e2e 2678 break;
ea278354 2679
97fd3a30
UD
2680 case 13:
2681 /* We might have some extra environment variable with length 13
2682 to handle. */
2683#ifdef EXTRA_LD_ENVVARS_13
2684 EXTRA_LD_ENVVARS_13
2685#endif
6bc6bd3b 2686 if (!__libc_enable_secure
97fd3a30 2687 && memcmp (envline, "USE_LOAD_BIAS", 13) == 0)
827b7087
UD
2688 {
2689 GLRO(dl_use_load_bias) = envline[14] == '1' ? -1 : 0;
2690 break;
2691 }
97fd3a30
UD
2692 break;
2693
14c44e2e
UD
2694 case 14:
2695 /* Where to place the profiling data file. */
6bc6bd3b 2696 if (!__libc_enable_secure
3e2040c8
UD
2697 && memcmp (envline, "PROFILE_OUTPUT", 14) == 0
2698 && envline[15] != '\0')
afdca0f2 2699 GLRO(dl_profile_output) = &envline[15];
14c44e2e 2700 break;
120b4c49 2701
32e6df36
UD
2702 case 16:
2703 /* The mode of the dynamic linker can be set. */
2704 if (memcmp (envline, "TRACE_PRELINKING", 16) == 0)
2705 {
2706 mode = trace;
afdca0f2
UD
2707 GLRO(dl_verbose) = 1;
2708 GLRO(dl_debug_mask) |= DL_DEBUG_PRELINK;
2709 GLRO(dl_trace_prelink) = &envline[17];
32e6df36
UD
2710 }
2711 break;
2712
14c44e2e
UD
2713 case 20:
2714 /* The mode of the dynamic linker can be set. */
67c94753 2715 if (memcmp (envline, "TRACE_LOADED_OBJECTS", 20) == 0)
14c44e2e
UD
2716 mode = trace;
2717 break;
e2102c14
UD
2718
2719 /* We might have some extra environment variable to handle. This
2720 is tricky due to the pre-processing of the length of the name
2721 in the switch statement here. The code here assumes that added
2722 environment variables have a different length. */
2723#ifdef EXTRA_LD_ENVVARS
2724 EXTRA_LD_ENVVARS
2725#endif
ea278354
UD
2726 }
2727 }
2728
3e2040c8
UD
2729 /* The caller wants this information. */
2730 *modep = mode;
2731
4bae5567
UD
2732 /* Extra security for SUID binaries. Remove all dangerous environment
2733 variables. */
6bc6bd3b 2734 if (__builtin_expect (__libc_enable_secure, 0))
4bae5567 2735 {
c95f3fd4 2736 static const char unsecure_envvars[] =
4bae5567
UD
2737#ifdef EXTRA_UNSECURE_ENVVARS
2738 EXTRA_UNSECURE_ENVVARS
2739#endif
c95f3fd4
UD
2740 UNSECURE_ENVVARS;
2741 const char *nextp;
2742
2743 nextp = unsecure_envvars;
2744 do
2745 {
2746 unsetenv (nextp);
9710f75d
UD
2747 /* We could use rawmemchr but this need not be fast. */
2748 nextp = (char *) (strchr) (nextp, '\0') + 1;
c95f3fd4
UD
2749 }
2750 while (*nextp != '\0');
74955460
UD
2751
2752 if (__access ("/etc/suid-debug", F_OK) != 0)
3a56ea26 2753 {
67e58f39 2754#if !HAVE_TUNABLES
00a12162 2755 unsetenv ("MALLOC_CHECK_");
67e58f39 2756#endif
f57a3c94 2757 GLRO(dl_debug_mask) = 0;
3a56ea26 2758 }
f57a3c94
RM
2759
2760 if (mode != normal)
2761 _exit (5);
4bae5567 2762 }
7dea968e
UD
2763 /* If we have to run the dynamic linker in debugging mode and the
2764 LD_DEBUG_OUTPUT environment variable is given, we write the debug
2765 messages to this file. */
3e2040c8 2766 else if (any_debug && debug_output != NULL)
7dea968e 2767 {
5f2de337 2768 const int flags = O_WRONLY | O_APPEND | O_CREAT | O_NOFOLLOW;
7a2fd787
UD
2769 size_t name_len = strlen (debug_output);
2770 char buf[name_len + 12];
2771 char *startp;
2772
2773 buf[name_len + 11] = '\0';
9710f75d 2774 startp = _itoa (__getpid (), &buf[name_len + 11], 10, 0);
7a2fd787
UD
2775 *--startp = '.';
2776 startp = memcpy (startp - name_len, debug_output, name_len);
2777
329ea513 2778 GLRO(dl_debug_fd) = __open64_nocancel (startp, flags, DEFFILEMODE);
dd70526e 2779 if (GLRO(dl_debug_fd) == -1)
7dea968e 2780 /* We use standard output if opening the file failed. */
dd70526e 2781 GLRO(dl_debug_fd) = STDOUT_FILENO;
7dea968e 2782 }
ea278354 2783}
db276fa1 2784
1e372ded
AZ
2785#if HP_TIMING_INLINE
2786static void
2787print_statistics_item (const char *title, hp_timing_t time,
2788 hp_timing_t total)
2789{
2790 char cycles[HP_TIMING_PRINT_SIZE];
2791 HP_TIMING_PRINT (cycles, sizeof (cycles), time);
2792
2793 char relative[3 * sizeof (hp_timing_t) + 2];
2794 char *cp = _itoa ((1000ULL * time) / total, relative + sizeof (relative),
2795 10, 0);
2796 /* Sets the decimal point. */
2797 char *wp = relative;
2798 switch (relative + sizeof (relative) - cp)
2799 {
2800 case 3:
2801 *wp++ = *cp++;
2802 /* Fall through. */
2803 case 2:
2804 *wp++ = *cp++;
2805 /* Fall through. */
2806 case 1:
2807 *wp++ = '.';
2808 *wp++ = *cp++;
2809 }
2810 *wp = '\0';
2811 _dl_debug_printf ("%s: %s cycles (%s%%)\n", title, cycles, relative);
2812}
2813#endif
db276fa1
UD
2814
2815/* Print the various times we collected. */
2816static void
ee600e3f 2817__attribute ((noinline))
1e372ded 2818print_statistics (const hp_timing_t *rtld_total_timep)
db276fa1 2819{
1e372ded
AZ
2820#if HP_TIMING_INLINE
2821 {
2822 char cycles[HP_TIMING_PRINT_SIZE];
2823 HP_TIMING_PRINT (cycles, sizeof (cycles), *rtld_total_timep);
2824 _dl_debug_printf ("\nruntime linker statistics:\n"
2825 " total startup time in dynamic loader: %s cycles\n",
2826 cycles);
2827 print_statistics_item (" time needed for relocation",
2828 relocate_time, *rtld_total_timep);
2829 }
1531e094 2830#endif
a21a20a3
UD
2831
2832 unsigned long int num_relative_relocations = 0;
22c83193 2833 for (Lmid_t ns = 0; ns < GL(dl_nns); ++ns)
a21a20a3 2834 {
c120d94d
UD
2835 if (GL(dl_ns)[ns]._ns_loaded == NULL)
2836 continue;
2837
c0f62c56 2838 struct r_scope_elem *scope = &GL(dl_ns)[ns]._ns_loaded->l_searchlist;
a21a20a3 2839
c0f62c56
UD
2840 for (unsigned int i = 0; i < scope->r_nlist; i++)
2841 {
2842 struct link_map *l = scope->r_list [i];
2843
c120d94d 2844 if (l->l_addr != 0 && l->l_info[VERSYMIDX (DT_RELCOUNT)])
c0f62c56
UD
2845 num_relative_relocations
2846 += l->l_info[VERSYMIDX (DT_RELCOUNT)]->d_un.d_val;
c120d94d
UD
2847#ifndef ELF_MACHINE_REL_RELATIVE
2848 /* Relative relocations are processed on these architectures if
2849 library is loaded to different address than p_vaddr or
2850 if not prelinked. */
2851 if ((l->l_addr != 0 || !l->l_info[VALIDX(DT_GNU_PRELINKED)])
2852 && l->l_info[VERSYMIDX (DT_RELACOUNT)])
2853#else
2854 /* On e.g. IA-64 or Alpha, relative relocations are processed
2855 only if library is loaded to different address than p_vaddr. */
2856 if (l->l_addr != 0 && l->l_info[VERSYMIDX (DT_RELACOUNT)])
2857#endif
c0f62c56
UD
2858 num_relative_relocations
2859 += l->l_info[VERSYMIDX (DT_RELACOUNT)]->d_un.d_val;
2860 }
a21a20a3
UD
2861 }
2862
42af49f8
UD
2863 _dl_debug_printf (" number of relocations: %lu\n"
2864 " number of relocations from cache: %lu\n"
2865 " number of relative relocations: %lu\n",
2866 GL(dl_num_relocations),
2867 GL(dl_num_cache_relocations),
154d10bd 2868 num_relative_relocations);
db276fa1 2869
1e372ded
AZ
2870#if HP_TIMING_INLINE
2871 print_statistics_item (" time needed to load objects",
2872 load_time, *rtld_total_timep);
1531e094 2873#endif
db276fa1 2874}
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