summary refs log tree commit diff
path: root/elf/dl-load.c
blob: 157d827419ace75438d3bd64721c7f2c452c19d9 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
/* Map in a shared object's segments from the file.
   Copyright (C) 1995,96,97,98,99,2000,2001 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public License as
   published by the Free Software Foundation; either version 2 of the
   License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#include <elf.h>
#include <errno.h>
#include <fcntl.h>
#include <libintl.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <ldsodefs.h>
#include <sys/mman.h>
#include <sys/param.h>
#include <sys/stat.h>
#include <sys/types.h>
#include "dynamic-link.h"
#include <stdio-common/_itoa.h>

#include <dl-dst.h>

/* On some systems, no flag bits are given to specify file mapping.  */
#ifndef MAP_FILE
# define MAP_FILE	0
#endif

/* The right way to map in the shared library files is MAP_COPY, which
   makes a virtual copy of the data at the time of the mmap call; this
   guarantees the mapped pages will be consistent even if the file is
   overwritten.  Some losing VM systems like Linux's lack MAP_COPY.  All we
   get is MAP_PRIVATE, which copies each page when it is modified; this
   means if the file is overwritten, we may at some point get some pages
   from the new version after starting with pages from the old version.  */
#ifndef MAP_COPY
# define MAP_COPY	MAP_PRIVATE
#endif

/* Some systems link their relocatable objects for another base address
   than 0.  We want to know the base address for these such that we can
   subtract this address from the segment addresses during mapping.
   This results in a more efficient address space usage.  Defaults to
   zero for almost all systems.  */
#ifndef MAP_BASE_ADDR
# define MAP_BASE_ADDR(l)	0
#endif


#include <endian.h>
#if BYTE_ORDER == BIG_ENDIAN
# define byteorder ELFDATA2MSB
#elif BYTE_ORDER == LITTLE_ENDIAN
# define byteorder ELFDATA2LSB
#else
# error "Unknown BYTE_ORDER " BYTE_ORDER
# define byteorder ELFDATANONE
#endif

#define STRING(x) __STRING (x)

#ifdef MAP_ANON
/* The fd is not examined when using MAP_ANON.  */
# define ANONFD -1
#else
int _dl_zerofd = -1;
# define ANONFD _dl_zerofd
#endif

/* Handle situations where we have a preferred location in memory for
   the shared objects.  */
#ifdef ELF_PREFERRED_ADDRESS_DATA
ELF_PREFERRED_ADDRESS_DATA;
#endif
#ifndef ELF_PREFERRED_ADDRESS
# define ELF_PREFERRED_ADDRESS(loader, maplength, mapstartpref) (mapstartpref)
#endif
#ifndef ELF_FIXED_ADDRESS
# define ELF_FIXED_ADDRESS(loader, mapstart) ((void) 0)
#endif

/* Type for the buffer we put the ELF header and hopefully the program
   header.  This buffer does not really have to be too large.  In most
   cases the program header follows the ELF header directly.  If this
   is not the case all bets are off and we can make the header arbitrarily
   large and still won't get it read.  This means the only question is
   how large are the ELF and program header combined.  The ELF header
   in 64-bit files is 56 bytes long.  Each program header entry is again
   56 bytes long.  I.e., even with a file which has 17 program header
   entries we only have to read 1kB.  And 17 program header entries is
   plenty, normal files have < 10.  If this heuristic should really fail
   for some file the code in `_dl_map_object_from_fd' knows how to
   recover.  */
struct filebuf
{
  ssize_t len;
  char buf[1024];
};

size_t _dl_pagesize;

int _dl_clktck;

extern const char *_dl_platform;
extern size_t _dl_platformlen;

/* The object to be initialized first.  */
struct link_map *_dl_initfirst;

/* This is the decomposed LD_LIBRARY_PATH search path.  */
static struct r_search_path_struct env_path_list;

/* List of the hardware capabilities we might end up using.  */
static const struct r_strlenpair *capstr;
static size_t ncapstr;
static size_t max_capstrlen;

const unsigned char _dl_pf_to_prot[8] =
{
  [0] = PROT_NONE,
  [PF_R] = PROT_READ,
  [PF_W] = PROT_WRITE,
  [PF_R | PF_W] = PROT_READ | PROT_WRITE,
  [PF_X] = PROT_EXEC,
  [PF_R | PF_X] = PROT_READ | PROT_EXEC,
  [PF_W | PF_X] = PROT_WRITE | PROT_EXEC,
  [PF_R | PF_W | PF_X] = PROT_READ | PROT_WRITE | PROT_EXEC
};


/* Get the generated information about the trusted directories.  */
#include "trusted-dirs.h"

static const char system_dirs[] = SYSTEM_DIRS;
static const size_t system_dirs_len[] =
{
  SYSTEM_DIRS_LEN
};
#define nsystem_dirs_len \
  (sizeof (system_dirs_len) / sizeof (system_dirs_len[0]))


/* Local version of `strdup' function.  */
static inline char *
local_strdup (const char *s)
{
  size_t len = strlen (s) + 1;
  void *new = malloc (len);

  if (new == NULL)
    return NULL;

  return (char *) memcpy (new, s, len);
}


size_t
_dl_dst_count (const char *name, int is_path)
{
  const char *const start = name;
  size_t cnt = 0;

  do
    {
      size_t len = 1;

      /* $ORIGIN is not expanded for SUID/GUID programs.

	 Note that it is no bug that the strings in the first two `strncmp'
	 calls are longer than the sequence which is actually tested.  */
      if ((((strncmp (&name[1], "ORIGIN}", 6) == 0
	     && (!__libc_enable_secure
		 || ((name[7] == '\0' || (is_path && name[7] == ':'))
		     && (name == start || (is_path && name[-1] == ':'))))
	     && (len = 7) != 0)
	    || (strncmp (&name[1], "PLATFORM}", 8) == 0 && (len = 9) != 0))
	   && (name[len] == '\0' || name[len] == '/'
	       || (is_path && name[len] == ':')))
	  || (name[1] == '{'
	      && ((strncmp (&name[2], "ORIGIN}", 7) == 0
		   && (!__libc_enable_secure
		       || ((name[9] == '\0' || (is_path && name[9] == ':'))
			   && (name == start || (is_path && name[-1] == ':'))))
		   && (len = 9) != 0)
		  || (strncmp (&name[2], "PLATFORM}", 9) == 0
		      && (len = 11) != 0))))
	++cnt;

      name = strchr (name + len, '$');
    }
  while (name != NULL);

  return cnt;
}


char *
_dl_dst_substitute (struct link_map *l, const char *name, char *result,
		    int is_path)
{
  const char *const start = name;
  char *last_elem, *wp;

  /* Now fill the result path.  While copying over the string we keep
     track of the start of the last path element.  When we come accross
     a DST we copy over the value or (if the value is not available)
     leave the entire path element out.  */
  last_elem = wp = result;

  do
    {
      if (*name == '$')
	{
	  const char *repl;
	  size_t len;

	  /* Note that it is no bug that the strings in the first two `strncmp'
	     calls are longer than the sequence which is actually tested.  */
	  if ((((strncmp (&name[1], "ORIGIN}", 6) == 0 && (len = 7) != 0)
		|| (strncmp (&name[1], "PLATFORM}", 8) == 0 && (len = 9) != 0))
	       && (name[len] == '\0' || name[len] == '/'
		   || (is_path && name[len] == ':')))
	      || (name[1] == '{'
		  && ((strncmp (&name[2], "ORIGIN}", 7) == 0 && (len = 9) != 0)
		      || (strncmp (&name[2], "PLATFORM}", 9) == 0
			  && (len = 11) != 0))))
	    {
	      repl = ((len == 7 || name[2] == 'O')
		      ? (__libc_enable_secure
			 && ((name[len] != '\0'
			      && (!is_path || name[len] != ':'))
			     || (name != start
				 && (!is_path || name[-1] != ':')))
			 ? NULL : l->l_origin)
		      : _dl_platform);

	      if (repl != NULL && repl != (const char *) -1)
		{
		  wp = __stpcpy (wp, repl);
		  name += len;
		}
	      else
		{
		  /* We cannot use this path element, the value of the
		     replacement is unknown.  */
		  wp = last_elem;
		  name += len;
		  while (*name != '\0' && (!is_path || *name != ':'))
		    ++name;
		}
	    }
	  else
	    /* No DST we recognize.  */
	    *wp++ = *name++;
	}
      else if (is_path && *name == ':')
	{
	  *wp++ = *name++;
	  last_elem = wp;
	}
      else
	*wp++ = *name++;
    }
  while (*name != '\0');

  *wp = '\0';

  return result;
}


/* Return copy of argument with all recognized dynamic string tokens
   ($ORIGIN and $PLATFORM for now) replaced.  On some platforms it
   might not be possible to determine the path from which the object
   belonging to the map is loaded.  In this case the path element
   containing $ORIGIN is left out.  */
static char *
expand_dynamic_string_token (struct link_map *l, const char *s)
{
  /* We make two runs over the string.  First we determine how large the
     resulting string is and then we copy it over.  Since this is now
     frequently executed operation we are looking here not for performance
     but rather for code size.  */
  size_t cnt;
  size_t total;
  char *result;

  /* Determine the number of DST elements.  */
  cnt = DL_DST_COUNT (s, 1);

  /* If we do not have to replace anything simply copy the string.  */
  if (cnt == 0)
    return local_strdup (s);

  /* Determine the length of the substituted string.  */
  total = DL_DST_REQUIRED (l, s, strlen (s), cnt);

  /* Allocate the necessary memory.  */
  result = (char *) malloc (total + 1);
  if (result == NULL)
    return NULL;

  return DL_DST_SUBSTITUTE (l, s, result, 1);
}


/* Add `name' to the list of names for a particular shared object.
   `name' is expected to have been allocated with malloc and will
   be freed if the shared object already has this name.
   Returns false if the object already had this name.  */
static void
internal_function
add_name_to_object (struct link_map *l, const char *name)
{
  struct libname_list *lnp, *lastp;
  struct libname_list *newname;
  size_t name_len;

  lastp = NULL;
  for (lnp = l->l_libname; lnp != NULL; lastp = lnp, lnp = lnp->next)
    if (strcmp (name, lnp->name) == 0)
      return;

  name_len = strlen (name) + 1;
  newname = (struct libname_list *) malloc (sizeof *newname + name_len);
  if (newname == NULL)
    {
      /* No more memory.  */
      _dl_signal_error (ENOMEM, name, N_("cannot allocate name record"));
      return;
    }
  /* The object should have a libname set from _dl_new_object.  */
  assert (lastp != NULL);

  newname->name = memcpy (newname + 1, name, name_len);
  newname->next = NULL;
  newname->dont_free = 0;
  lastp->next = newname;
}

/* All known directories in sorted order.  */
struct r_search_path_elem *_dl_all_dirs;

/* All directories after startup.  */
struct r_search_path_elem *_dl_init_all_dirs;

/* Standard search directories.  */
static struct r_search_path_struct rtld_search_dirs;

static size_t max_dirnamelen;

static inline struct r_search_path_elem **
fillin_rpath (char *rpath, struct r_search_path_elem **result, const char *sep,
	      int check_trusted, const char *what, const char *where)
{
  char *cp;
  size_t nelems = 0;

  while ((cp = __strsep (&rpath, sep)) != NULL)
    {
      struct r_search_path_elem *dirp;
      size_t len = strlen (cp);

      /* `strsep' can pass an empty string.  This has to be
         interpreted as `use the current directory'. */
      if (len == 0)
	{
	  static const char curwd[] = "./";
	  cp = (char *) curwd;
	}

      /* Remove trailing slashes (except for "/").  */
      while (len > 1 && cp[len - 1] == '/')
	--len;

      /* Now add one if there is none so far.  */
      if (len > 0 && cp[len - 1] != '/')
	cp[len++] = '/';

      /* See if this directory is already known.  */
      for (dirp = _dl_all_dirs; dirp != NULL; dirp = dirp->next)
	if (dirp->dirnamelen == len && memcmp (cp, dirp->dirname, len) == 0)
	  break;

      if (dirp != NULL)
	{
	  /* It is available, see whether it's on our own list.  */
	  size_t cnt;
	  for (cnt = 0; cnt < nelems; ++cnt)
	    if (result[cnt] == dirp)
	      break;

	  if (cnt == nelems)
	    result[nelems++] = dirp;
	}
      else
	{
	  size_t cnt;
	  enum r_dir_status init_val;
	  size_t where_len = where ? strlen (where) + 1 : 0;

	  /* It's a new directory.  Create an entry and add it.  */
	  dirp = (struct r_search_path_elem *)
	    malloc (sizeof (*dirp) + ncapstr * sizeof (enum r_dir_status)
		    + where_len + len + 1);
	  if (dirp == NULL)
	    _dl_signal_error (ENOMEM, NULL,
			      N_("cannot create cache for search path"));

	  dirp->dirname = ((char *) dirp + sizeof (*dirp)
			   + ncapstr * sizeof (enum r_dir_status));
	  *((char *) __mempcpy ((char *) dirp->dirname, cp, len)) = '\0';
	  dirp->dirnamelen = len;

	  if (len > max_dirnamelen)
	    max_dirnamelen = len;

	  /* Make sure we don't use untrusted directories if we run SUID.  */
	  if (__builtin_expect (check_trusted, 0))
	    {
	      const char *trun = system_dirs;
	      size_t idx;

	      /* By default we don't trust anything.  */
	      init_val = nonexisting;

	      /* All trusted directories must be complete names.  */
	      if (cp[0] == '/')
		{
		  for (idx = 0; idx < nsystem_dirs_len; ++idx)
		    {
		      if (len == system_dirs_len[idx]
			  && memcmp (trun, cp, len) == 0)
			/* Found it.  */
			break;

		      trun += system_dirs_len[idx] + 1;
		    }

		  if (idx < nsystem_dirs_len)
		    /* It's a trusted directory so allow checking for it.  */
		    init_val = unknown;
		}
	    }
	  else
	    /* We don't have to check for trusted directories and can
	       accept everything.  We have to make sure all the
	       relative directories are never ignored.  The current
	       directory might change and all our saved information
	       would be void.  */
	    init_val = cp[0] != '/' ? existing : unknown;

	  for (cnt = 0; cnt < ncapstr; ++cnt)
	    dirp->status[cnt] = init_val;

	  dirp->what = what;
	  if (__builtin_expect (where != NULL, 1))
	    dirp->where = memcpy ((char *) dirp + sizeof (*dirp) + len + 1
				  + ncapstr * sizeof (enum r_dir_status),
				  where, where_len);
	  else
	    dirp->where = NULL;

	  dirp->next = _dl_all_dirs;
	  _dl_all_dirs = dirp;

	  /* Put it in the result array.  */
	  result[nelems++] = dirp;
	}
    }

  /* Terminate the array.  */
  result[nelems] = NULL;

  return result;
}


static void
internal_function
decompose_rpath (struct r_search_path_struct *sps,
		 const char *rpath, struct link_map *l, const char *what)
{
  /* Make a copy we can work with.  */
  const char *where = l->l_name;
  char *copy;
  char *cp;
  struct r_search_path_elem **result;
  size_t nelems;

  /* First see whether we must forget the RUNPATH and RPATH from this
     object.  */
  if (__builtin_expect (_dl_inhibit_rpath != NULL, 0) && !__libc_enable_secure)
    {
      const char *found = strstr (_dl_inhibit_rpath, where);
      if (found != NULL)
	{
	  size_t len = strlen (where);
	  if ((found == _dl_inhibit_rpath || found[-1] == ':')
	      && (found[len] == '\0' || found[len] == ':'))
	    {
	      /* This object is on the list of objects for which the
		 RUNPATH and RPATH must not be used.  */
	      result = (struct r_search_path_elem **)
		malloc (sizeof (*result));
	      if (result == NULL)
		_dl_signal_error (ENOMEM, NULL,
				  N_("cannot create cache for search path"));
	      result[0] = NULL;

	      sps->dirs = result;
	      sps->malloced = 1;

	      return;
	    }
	}
    }

  /* Make a writable copy.  At the same time expand possible dynamic
     string tokens.  */
  copy = expand_dynamic_string_token (l, rpath);
  if (copy == NULL)
    _dl_signal_error (ENOMEM, NULL, N_("cannot create RUNPATH/RPATH copy"));

  /* Count the number of necessary elements in the result array.  */
  nelems = 0;
  for (cp = copy; *cp != '\0'; ++cp)
    if (*cp == ':')
      ++nelems;

  /* Allocate room for the result.  NELEMS + 1 is an upper limit for the
     number of necessary entries.  */
  result = (struct r_search_path_elem **) malloc ((nelems + 1 + 1)
						  * sizeof (*result));
  if (result == NULL)
    _dl_signal_error (ENOMEM, NULL, N_("cannot create cache for search path"));

  fillin_rpath (copy, result, ":", 0, what, where);

  /* Free the copied RPATH string.  `fillin_rpath' make own copies if
     necessary.  */
  free (copy);

  sps->dirs = result;
  /* The caller will change this value if we haven't used a real malloc.  */
  sps->malloced = 1;
}


void
internal_function
_dl_init_paths (const char *llp)
{
  size_t idx;
  const char *strp;
  struct r_search_path_elem *pelem, **aelem;
  size_t round_size;
#ifdef SHARED
  struct link_map *l;
#endif

  /* Fill in the information about the application's RPATH and the
     directories addressed by the LD_LIBRARY_PATH environment variable.  */

  /* Get the capabilities.  */
  capstr = _dl_important_hwcaps (_dl_platform, _dl_platformlen,
				 &ncapstr, &max_capstrlen);

  /* First set up the rest of the default search directory entries.  */
  aelem = rtld_search_dirs.dirs = (struct r_search_path_elem **)
    malloc ((nsystem_dirs_len + 1) * sizeof (struct r_search_path_elem *));
  if (rtld_search_dirs.dirs == NULL)
    _dl_signal_error (ENOMEM, NULL, N_("cannot create search path array"));

  round_size = ((2 * sizeof (struct r_search_path_elem) - 1
		 + ncapstr * sizeof (enum r_dir_status))
		/ sizeof (struct r_search_path_elem));

  rtld_search_dirs.dirs[0] = (struct r_search_path_elem *)
    malloc ((sizeof (system_dirs) / sizeof (system_dirs[0]))
	    * round_size * sizeof (struct r_search_path_elem));
  if (rtld_search_dirs.dirs[0] == NULL)
    _dl_signal_error (ENOMEM, NULL, N_("cannot create cache for search path"));

  rtld_search_dirs.malloced = 0;
  pelem = _dl_all_dirs = rtld_search_dirs.dirs[0];
  strp = system_dirs;
  idx = 0;

  do
    {
      size_t cnt;

      *aelem++ = pelem;

      pelem->what = "system search path";
      pelem->where = NULL;

      pelem->dirname = strp;
      pelem->dirnamelen = system_dirs_len[idx];
      strp += system_dirs_len[idx] + 1;

      /* System paths must be absolute.  */
      assert (pelem->dirname[0] == '/');
      for (cnt = 0; cnt < ncapstr; ++cnt)
	pelem->status[cnt] = unknown;

      pelem->next = (++idx == nsystem_dirs_len ? NULL : (pelem + round_size));

      pelem += round_size;
    }
  while (idx < nsystem_dirs_len);

  max_dirnamelen = SYSTEM_DIRS_MAX_LEN;
  *aelem = NULL;

#ifdef SHARED
  /* This points to the map of the main object.  */
  l = _dl_loaded;
  if (l != NULL)
    {
      assert (l->l_type != lt_loaded);

      if (l->l_info[DT_RUNPATH])
	{
	  /* Allocate room for the search path and fill in information
	     from RUNPATH.  */
	  decompose_rpath (&l->l_runpath_dirs,
			   (const void *) (D_PTR (l, l_info[DT_STRTAB])
					   + l->l_info[DT_RUNPATH]->d_un.d_val),
			   l, "RUNPATH");

	  /* The RPATH is ignored.  */
	  l->l_rpath_dirs.dirs = (void *) -1;
	}
      else
	{
	  l->l_runpath_dirs.dirs = (void *) -1;

	  if (l->l_info[DT_RPATH])
	    {
	      /* Allocate room for the search path and fill in information
		 from RPATH.  */
	      decompose_rpath (&l->l_rpath_dirs,
			       (const void *) (D_PTR (l, l_info[DT_STRTAB])
					       + l->l_info[DT_RPATH]->d_un.d_val),
			       l, "RPATH");
	      l->l_rpath_dirs.malloced = 0;
	    }
	  else
	    l->l_rpath_dirs.dirs = (void *) -1;
	}
    }
#endif	/* SHARED */

  if (llp != NULL && *llp != '\0')
    {
      size_t nllp;
      const char *cp = llp;
      char *llp_tmp = strdupa (llp);

      /* Decompose the LD_LIBRARY_PATH contents.  First determine how many
	 elements it has.  */
      nllp = 1;
      while (*cp)
	{
	  if (*cp == ':' || *cp == ';')
	    ++nllp;
	  ++cp;
	}

      env_path_list.dirs = (struct r_search_path_elem **)
	malloc ((nllp + 1) * sizeof (struct r_search_path_elem *));
      if (env_path_list.dirs == NULL)
	_dl_signal_error (ENOMEM, NULL,
			  N_("cannot create cache for search path"));

      (void) fillin_rpath (llp_tmp, env_path_list.dirs, ":;",
			   __libc_enable_secure, "LD_LIBRARY_PATH", NULL);

      if (env_path_list.dirs[0] == NULL)
	{
	  free (env_path_list.dirs);
	  env_path_list.dirs = (void *) -1;
	}

      env_path_list.malloced = 0;
    }
  else
    env_path_list.dirs = (void *) -1;

  /* Remember the last search directory added at startup.  */
  _dl_init_all_dirs = _dl_all_dirs;
}


/* Think twice before changing anything in this function.  It is placed
   here and prepared using the `alloca' magic to prevent it from being
   inlined.  The function is only called in case of an error.  But then
   performance does not count.  The function used to be "inlinable" and
   the compiled did so all the time.  This increased the code size for
   absolutely no good reason.  */
#define LOSE(code, s) lose (code, fd, name, realname, l, s)
static void
__attribute__ ((noreturn))
lose (int code, int fd, const char *name, char *realname, struct link_map *l,
      const char *msg)
{
  /* The use of `alloca' here looks ridiculous but it helps.  The goal
     is to avoid the function from being inlined.  There is no official
     way to do this so we use this trick.  gcc never inlines functions
     which use `alloca'.  */
  int *a = alloca (sizeof (int));
  a[0] = fd;
  (void) __close (a[0]);
  if (l != NULL)
    {
      /* Remove the stillborn object from the list and free it.  */
      if (l->l_prev)
	l->l_prev->l_next = l->l_next;
      if (l->l_next)
	l->l_next->l_prev = l->l_prev;
      --_dl_nloaded;
      free (l);
    }
  free (realname);
  _dl_signal_error (code, name, msg);
}


/* Map in the shared object NAME, actually located in REALNAME, and already
   opened on FD.  */

#ifndef EXTERNAL_MAP_FROM_FD
static
#endif
struct link_map *
_dl_map_object_from_fd (const char *name, int fd, struct filebuf *fbp,
			char *realname, struct link_map *loader, int l_type,
			int mode)
{
  struct link_map *l = NULL;

  auto inline caddr_t map_segment (ElfW(Addr) mapstart, size_t len,
				   int prot, int fixed, off_t offset);

  inline caddr_t map_segment (ElfW(Addr) mapstart, size_t len,
			      int prot, int fixed, off_t offset)
    {
      caddr_t mapat = __mmap ((caddr_t) mapstart, len, prot,
			      fixed|MAP_COPY|MAP_FILE,
			      fd, offset);
      if (mapat == MAP_FAILED)
	LOSE (errno, N_("failed to map segment from shared object"));
      return mapat;
    }

  const ElfW(Ehdr) *header;
  const ElfW(Phdr) *phdr;
  const ElfW(Phdr) *ph;
  size_t maplength;
  int type;
  struct stat64 st;

  /* Get file information.  */
  if (__fxstat64 (_STAT_VER, fd, &st) < 0)
    LOSE (errno, N_("cannot stat shared object"));

  /* Look again to see if the real name matched another already loaded.  */
  for (l = _dl_loaded; l; l = l->l_next)
    if (l->l_ino == st.st_ino && l->l_dev == st.st_dev)
      {
	/* The object is already loaded.
	   Just bump its reference count and return it.  */
	__close (fd);

	/* If the name is not in the list of names for this object add
	   it.  */
	free (realname);
	add_name_to_object (l, name);

	return l;
      }

  if (mode & RTLD_NOLOAD)
    /* We are not supposed to load the object unless it is already
       loaded.  So return now.  */
    return NULL;

  /* Print debugging message.  */
  if (__builtin_expect (_dl_debug_files, 0))
    _dl_debug_message (1, "file=", name, ";  generating link map\n", NULL);

  /* This is the ELF header.  We read it in `open_verify'.  */
  header = (void *) fbp->buf;

#ifndef MAP_ANON
# define MAP_ANON 0
  if (_dl_zerofd == -1)
    {
      _dl_zerofd = _dl_sysdep_open_zero_fill ();
      if (_dl_zerofd == -1)
	{
	  __close (fd);
	  _dl_signal_error (errno, NULL, N_("cannot open zero fill device"));
	}
    }
#endif

  /* Enter the new object in the list of loaded objects.  */
  l = _dl_new_object (realname, name, l_type, loader);
  if (__builtin_expect (! l, 0))
    LOSE (ENOMEM, N_("cannot create shared object descriptor"));

  /* Extract the remaining details we need from the ELF header
     and then read in the program header table.  */
  l->l_entry = header->e_entry;
  type = header->e_type;
  l->l_phnum = header->e_phnum;

  maplength = header->e_phnum * sizeof (ElfW(Phdr));
  if (header->e_phoff + maplength <= fbp->len)
    phdr = (void *) (fbp->buf + header->e_phoff);
  else
    {
      phdr = alloca (maplength);
      __lseek (fd, SEEK_SET, header->e_phoff);
      if (__libc_read (fd, (void *) phdr, maplength) != maplength)
        LOSE (errno, N_("cannot read file data"));
    }

  {
    /* Scan the program header table, collecting its load commands.  */
    struct loadcmd
      {
	ElfW(Addr) mapstart, mapend, dataend, allocend;
	off_t mapoff;
	int prot;
      } loadcmds[l->l_phnum], *c;
    size_t nloadcmds = 0;

    /* The struct is initialized to zero so this is not necessary:
    l->l_ld = 0;
    l->l_phdr = 0;
    l->l_addr = 0; */
    for (ph = phdr; ph < &phdr[l->l_phnum]; ++ph)
      switch (ph->p_type)
	{
	  /* These entries tell us where to find things once the file's
	     segments are mapped in.  We record the addresses it says
	     verbatim, and later correct for the run-time load address.  */
	case PT_DYNAMIC:
	  l->l_ld = (void *) ph->p_vaddr;
	  l->l_ldnum = ph->p_memsz / sizeof (ElfW(Dyn));
	  break;
	case PT_PHDR:
	  l->l_phdr = (void *) ph->p_vaddr;
	  break;

	case PT_LOAD:
	  /* A load command tells us to map in part of the file.
	     We record the load commands and process them all later.  */
	  if (ph->p_align % _dl_pagesize != 0)
	    LOSE (0, N_("ELF load command alignment not page-aligned"));
	  if ((ph->p_vaddr - ph->p_offset) % ph->p_align)
	    LOSE (0,
		  N_("ELF load command address/offset not properly aligned"));
	  {
	    struct loadcmd *c = &loadcmds[nloadcmds++];
	    c->mapstart = ph->p_vaddr & ~(ph->p_align - 1);
	    c->mapend = ((ph->p_vaddr + ph->p_filesz + _dl_pagesize - 1)
			 & ~(_dl_pagesize - 1));
	    c->dataend = ph->p_vaddr + ph->p_filesz;
	    c->allocend = ph->p_vaddr + ph->p_memsz;
	    c->mapoff = ph->p_offset & ~(ph->p_align - 1);

	    /* Optimize a common case.  */
	    if ((PF_R | PF_W | PF_X) == 7
		&& (PROT_READ | PROT_WRITE | PROT_EXEC) == 7)
	      c->prot = _dl_pf_to_prot[ph->p_flags & (PF_R | PF_W | PF_X)];
	    else
	      {
		c->prot = 0;
		if (ph->p_flags & PF_R)
		  c->prot |= PROT_READ;
		if (ph->p_flags & PF_W)
		  c->prot |= PROT_WRITE;
		if (ph->p_flags & PF_X)
		  c->prot |= PROT_EXEC;
	      }
	    break;
	  }
	}

    /* Now process the load commands and map segments into memory.  */
    c = loadcmds;

    /* Length of the sections to be loaded.  */
    maplength = loadcmds[nloadcmds - 1].allocend - c->mapstart;

    if (__builtin_expect (type, ET_DYN) == ET_DYN)
      {
	/* This is a position-independent shared object.  We can let the
	   kernel map it anywhere it likes, but we must have space for all
	   the segments in their specified positions relative to the first.
	   So we map the first segment without MAP_FIXED, but with its
	   extent increased to cover all the segments.  Then we remove
	   access from excess portion, and there is known sufficient space
	   there to remap from the later segments.

	   As a refinement, sometimes we have an address that we would
	   prefer to map such objects at; but this is only a preference,
	   the OS can do whatever it likes. */
	ElfW(Addr) mappref;
	mappref = (ELF_PREFERRED_ADDRESS (loader, maplength, c->mapstart)
		   - MAP_BASE_ADDR (l));

	/* Remember which part of the address space this object uses.  */
	l->l_map_start = (ElfW(Addr)) map_segment (mappref, maplength, c->prot,
						   0, c->mapoff);
	l->l_map_end = l->l_map_start + maplength;
	l->l_addr = l->l_map_start - c->mapstart;

	/* Change protection on the excess portion to disallow all access;
	   the portions we do not remap later will be inaccessible as if
	   unallocated.  Then jump into the normal segment-mapping loop to
	   handle the portion of the segment past the end of the file
	   mapping.  */
	__mprotect ((caddr_t) (l->l_addr + c->mapend),
		    loadcmds[nloadcmds - 1].allocend - c->mapend,
		    0);

	goto postmap;
      }
    else
      {
	/* This object is loaded at a fixed address.  This must never
           happen for objects loaded with dlopen().  */
	if (mode & __RTLD_DLOPEN)
	  {
	    LOSE (0, N_("cannot dynamically load executable"));
	  }

	/* Notify ELF_PREFERRED_ADDRESS that we have to load this one
	   fixed.  */
	ELF_FIXED_ADDRESS (loader, c->mapstart);
      }

    /* Remember which part of the address space this object uses.  */
    l->l_map_start = c->mapstart + l->l_addr;
    l->l_map_end = l->l_map_start + maplength;

    while (c < &loadcmds[nloadcmds])
      {
	if (c->mapend > c->mapstart)
	  /* Map the segment contents from the file.  */
	  map_segment (l->l_addr + c->mapstart, c->mapend - c->mapstart,
		       c->prot, MAP_FIXED, c->mapoff);

      postmap:
	if (l->l_phdr == 0
	    && c->mapoff <= header->e_phoff
	    && (c->mapend - c->mapstart + c->mapoff
		>= header->e_phoff + header->e_phnum * sizeof (ElfW(Phdr))))
	  /* Found the program header in this segment.  */
	  l->l_phdr = (void *) (c->mapstart + header->e_phoff - c->mapoff);

	if (c->allocend > c->dataend)
	  {
	    /* Extra zero pages should appear at the end of this segment,
	       after the data mapped from the file.   */
	    ElfW(Addr) zero, zeroend, zeropage;

	    zero = l->l_addr + c->dataend;
	    zeroend = l->l_addr + c->allocend;
	    zeropage = (zero + _dl_pagesize - 1) & ~(_dl_pagesize - 1);

	    if (zeroend < zeropage)
	      /* All the extra data is in the last page of the segment.
		 We can just zero it.  */
	      zeropage = zeroend;

	    if (zeropage > zero)
	      {
		/* Zero the final part of the last page of the segment.  */
		if ((c->prot & PROT_WRITE) == 0)
		  {
		    /* Dag nab it.  */
		    if (__mprotect ((caddr_t) (zero & ~(_dl_pagesize - 1)),
				    _dl_pagesize, c->prot|PROT_WRITE) < 0)
		      LOSE (errno, N_("cannot change memory protections"));
		  }
		memset ((void *) zero, 0, zeropage - zero);
		if ((c->prot & PROT_WRITE) == 0)
		  __mprotect ((caddr_t) (zero & ~(_dl_pagesize - 1)),
			      _dl_pagesize, c->prot);
	      }

	    if (zeroend > zeropage)
	      {
		/* Map the remaining zero pages in from the zero fill FD.  */
		caddr_t mapat;
		mapat = __mmap ((caddr_t) zeropage, zeroend - zeropage,
				c->prot, MAP_ANON|MAP_PRIVATE|MAP_FIXED,
				ANONFD, 0);
		if (mapat == MAP_FAILED)
		  LOSE (errno, N_("cannot map zero-fill pages"));
	      }
	  }

	++c;
      }

    if (l->l_phdr == NULL)
      {
	/* The program header is not contained in any of the segmenst.
	   We have to allocate memory ourself and copy it over from
	   out temporary place.  */
	ElfW(Phdr) *newp = (ElfW(Phdr) *) malloc (header->e_phnum
						  * sizeof (ElfW(Phdr)));
	if (newp == NULL)
	  LOSE (ENOMEM, N_("cannot allocate memory for program header"));

	l->l_phdr = memcpy (newp, phdr,
			    (header->e_phnum * sizeof (ElfW(Phdr))));
	l->l_phdr_allocated = 1;
      }
    else
      /* Adjust the PT_PHDR value by the runtime load address.  */
      (ElfW(Addr)) l->l_phdr += l->l_addr;
  }

  /* We are done mapping in the file.  We no longer need the descriptor.  */
  __close (fd);

  if (l->l_type == lt_library && type == ET_EXEC)
    l->l_type = lt_executable;

  if (l->l_ld == 0)
    {
      if (type == ET_DYN)
	LOSE (0, N_("object file has no dynamic section"));
    }
  else
    (ElfW(Addr)) l->l_ld += l->l_addr;

  l->l_entry += l->l_addr;

  if (__builtin_expect (_dl_debug_files, 0))
    {
      const size_t nibbles = sizeof (void *) * 2;
      char buf1[nibbles + 1];
      char buf2[nibbles + 1];
      char buf3[nibbles + 1];

      buf1[nibbles] = '\0';
      buf2[nibbles] = '\0';
      buf3[nibbles] = '\0';

      memset (buf1, '0', nibbles);
      memset (buf2, '0', nibbles);
      memset (buf3, '0', nibbles);
      _itoa_word ((unsigned long int) l->l_ld, &buf1[nibbles], 16, 0);
      _itoa_word ((unsigned long int) l->l_addr, &buf2[nibbles], 16, 0);
      _itoa_word (maplength, &buf3[nibbles], 16, 0);

      _dl_debug_message (1, "  dynamic: 0x", buf1, "  base: 0x", buf2,
			 "   size: 0x", buf3, "\n", NULL);
      memset (buf1, '0', nibbles);
      memset (buf2, '0', nibbles);
      memset (buf3, ' ', nibbles);
      _itoa_word ((unsigned long int) l->l_entry, &buf1[nibbles], 16, 0);
      _itoa_word ((unsigned long int) l->l_phdr, &buf2[nibbles], 16, 0);
      _itoa_word (l->l_phnum, &buf3[nibbles], 10, 0);
      _dl_debug_message (1, "    entry: 0x", buf1, "  phdr: 0x", buf2,
			 "  phnum:   ", buf3, "\n\n", NULL);
    }

  elf_get_dynamic_info (l);

  /* Make sure we are dlopen()ing an object which has the DF_1_NOOPEN
     flag set.  */
  if (__builtin_expect (l->l_flags_1 & DF_1_NOOPEN, 0)
      && (mode & __RTLD_DLOPEN))
    {
      /* Remove from the module list.  */
      assert (l->l_next == NULL);
#ifndef SHARED
      if (l->l_prev == NULL)
	/* No other module loaded.  */
	_dl_loaded = NULL;
      else
#endif
	l->l_prev->l_next = NULL;
      --_dl_nloaded;

      /* We are not supposed to load this object.  Free all resources.  */
      __munmap ((void *) l->l_map_start, l->l_map_end - l->l_map_start);

      free (l->l_libname);

      if (l->l_phdr_allocated)
	free ((void *) l->l_phdr);

      free (l);

      _dl_signal_error (0, name, N_("shared object cannot be dlopen()ed"));
    }

  if (l->l_info[DT_HASH])
    _dl_setup_hash (l);

  /* If this object has DT_SYMBOLIC set modify now its scope.  We don't
     have to do this for the main map.  */
  if (__builtin_expect (l->l_info[DT_SYMBOLIC] != NULL, 0)
	   && &l->l_searchlist != l->l_scope[0])
    {
      /* Create an appropriate searchlist.  It contains only this map.

	 XXX This is the definition of DT_SYMBOLIC in SysVr4.  The old
	 GNU ld.so implementation had a different interpretation which
	 is more reasonable.  We are prepared to add this possibility
	 back as part of a GNU extension of the ELF format.  */
      l->l_symbolic_searchlist.r_list =
	(struct link_map **) malloc (sizeof (struct link_map *));

      if (l->l_symbolic_searchlist.r_list == NULL)
	LOSE (ENOMEM, N_("cannot create searchlist"));

      l->l_symbolic_searchlist.r_list[0] = l;
      l->l_symbolic_searchlist.r_nlist = 1;
      l->l_symbolic_searchlist.r_duplist = l->l_symbolic_searchlist.r_list;
      l->l_symbolic_searchlist.r_nduplist = 1;

      /* Now move the existing entries one back.  */
      memmove (&l->l_scope[1], &l->l_scope[0],
	       sizeof (l->l_scope) - sizeof (l->l_scope[0]));

      /* Now add the new entry.  */
      l->l_scope[0] = &l->l_symbolic_searchlist;
    }

  /* Remember whether this object must be initialized first.  */
  if (l->l_flags_1 & DF_1_INITFIRST)
    _dl_initfirst = l;

  /* Finally the file information.  */
  l->l_dev = st.st_dev;
  l->l_ino = st.st_ino;

  return l;
}

/* Print search path.  */
static void
print_search_path (struct r_search_path_elem **list,
                   const char *what, const char *name)
{
  char buf[max_dirnamelen + max_capstrlen];
  int first = 1;

  _dl_debug_message (1, " search path=", NULL);

  while (*list != NULL && (*list)->what == what) /* Yes, ==.  */
    {
      char *endp = __mempcpy (buf, (*list)->dirname, (*list)->dirnamelen);
      size_t cnt;

      for (cnt = 0; cnt < ncapstr; ++cnt)
	if ((*list)->status[cnt] != nonexisting)
	  {
	    char *cp = __mempcpy (endp, capstr[cnt].str, capstr[cnt].len);
	    if (cp == buf || (cp == buf + 1 && buf[0] == '/'))
	      cp[0] = '\0';
	    else
	      cp[-1] = '\0';
	    _dl_debug_message (0, first ? "" : ":", buf, NULL);
	    first = 0;
	  }

      ++list;
    }

  if (name != NULL)
    _dl_debug_message (0, "\t\t(", what, " from file ",
			name[0] ? name : _dl_argv[0], ")\n", NULL);
  else
    _dl_debug_message (0, "\t\t(", what, ")\n", NULL);
}

/* Open a file and verify it is an ELF file for this architecture.  We
   ignore only ELF files for other architectures.  Non-ELF files and
   ELF files with different header information cause fatal errors since
   this could mean there is something wrong in the installation and the
   user might want to know about this.  */
static int
open_verify (const char *name, struct filebuf *fbp)
{
  /* This is the expected ELF header.  */
#define ELF32_CLASS ELFCLASS32
#define ELF64_CLASS ELFCLASS64
#ifndef VALID_ELF_HEADER
# define VALID_ELF_HEADER(hdr,exp,size)	(memcmp (hdr, exp, size) == 0)
# define VALID_ELF_OSABI(osabi)		(osabi == ELFOSABI_SYSV)
# define VALID_ELF_ABIVERSION(ver)	(ver == 0)
#endif
  static const unsigned char expected[EI_PAD] =
  {
    [EI_MAG0] = ELFMAG0,
    [EI_MAG1] = ELFMAG1,
    [EI_MAG2] = ELFMAG2,
    [EI_MAG3] = ELFMAG3,
    [EI_CLASS] = ELFW(CLASS),
    [EI_DATA] = byteorder,
    [EI_VERSION] = EV_CURRENT,
    [EI_OSABI] = ELFOSABI_SYSV,
    [EI_ABIVERSION] = 0
  };
  int fd;

  /* Open the file.  We always open files read-only.  */
  fd = __open (name, O_RDONLY);
  if (fd != -1)
    {
      ElfW(Ehdr) *ehdr;

      /* We successfully openened the file.  Now verify it is a file
	 we can use.  */
      __set_errno (0);
      fbp->len = __libc_read (fd, fbp->buf, sizeof (fbp->buf));

      /* This is where the ELF header is loaded.  */
      assert (sizeof (fbp->buf) > sizeof (ElfW(Ehdr)));
      ehdr = (ElfW(Ehdr) *) fbp->buf;

      /* Now run the tests.  */
      if (__builtin_expect (fbp->len < (ssize_t) sizeof (ElfW(Ehdr)), 0))
	lose (errno, fd, name, NULL, NULL,
	      errno == 0 ? N_("file too short") : N_("cannot read file data"));

      /* See whether the ELF header is what we expect.  */
      if (__builtin_expect (! VALID_ELF_HEADER (ehdr->e_ident, expected,
						EI_PAD), 0))
	{
	  /* Something is wrong.  */
	  if (*(Elf32_Word *) &ehdr->e_ident !=
#if BYTE_ORDER == LITTLE_ENDIAN
	      ((ELFMAG0 << (EI_MAG0 * 8)) |
	       (ELFMAG1 << (EI_MAG1 * 8)) |
	       (ELFMAG2 << (EI_MAG2 * 8)) |
	       (ELFMAG3 << (EI_MAG3 * 8)))
#else
	      ((ELFMAG0 << (EI_MAG3 * 8)) |
	       (ELFMAG1 << (EI_MAG2 * 8)) |
	       (ELFMAG2 << (EI_MAG1 * 8)) |
	       (ELFMAG3 << (EI_MAG0 * 8)))
#endif
	      )
	    lose (0, fd, name, NULL, NULL, N_("invalid ELF header"));

	  if (ehdr->e_ident[EI_CLASS] != ELFW(CLASS))
	    /* This is not a fatal error.  On architectures where
	       32-bit and 64-bit binaries can be run this might
	       happen.  */
	    goto close_and_out;

	  if (ehdr->e_ident[EI_DATA] != byteorder)
	    {
	      if (BYTE_ORDER == BIG_ENDIAN)
		lose (0, fd, name, NULL, NULL,
		      "ELF file data encoding not big-endian");
	      else
		lose (0, fd, name, NULL, NULL,
		      "ELF file data encoding not little-endian");
	    }
	  if (ehdr->e_ident[EI_VERSION] != EV_CURRENT)
	    lose (0, fd, name, NULL, NULL,
		  N_("ELF file version ident does not match current one"));
	  /* XXX We should be able so set system specific versions which are
	     allowed here.  */
	  if (!VALID_ELF_OSABI (ehdr->e_ident[EI_OSABI]))
	    lose (0, fd, name, NULL, NULL, N_("ELF file OS ABI invalid"));
	  if (!VALID_ELF_ABIVERSION (ehdr->e_ident[EI_ABIVERSION]))
	    lose (0, fd, name, NULL, NULL,
		  N_("ELF file ABI version invalid"));
	  lose (0, fd, name, NULL, NULL, N_("internal error"));
	}

      if (__builtin_expect (ehdr->e_version, EV_CURRENT) != EV_CURRENT)
	lose (0, fd, name, NULL, NULL,
	      N_("ELF file version does not match current one"));
      if (! __builtin_expect (elf_machine_matches_host (ehdr), 1))
	{
	close_and_out:
	  __close (fd);
	  __set_errno (ENOENT);
	  fd = -1;
	}
      else if (__builtin_expect (ehdr->e_phentsize, sizeof (ElfW(Phdr)))
	       != sizeof (ElfW(Phdr)))
	lose (0, fd, name, NULL, NULL,
	      N_("ELF file's phentsize not the expected size"));
      else if (__builtin_expect (ehdr->e_type, ET_DYN) != ET_DYN
	       && __builtin_expect (ehdr->e_type, ET_EXEC) != ET_EXEC)
	lose (0, fd, name, NULL, NULL,
	      N_("only ET_DYN and ET_EXEC can be loaded"));
    }

  return fd;
}

/* Try to open NAME in one of the directories in *DIRSP.
   Return the fd, or -1.  If successful, fill in *REALNAME
   with the malloc'd full directory name.  If it turns out
   that none of the directories in *DIRSP exists, *DIRSP is
   replaced with (void *) -1, and the old value is free()d
   if MAY_FREE_DIRS is true.  */

static int
open_path (const char *name, size_t namelen, int preloaded,
	   struct r_search_path_struct *sps, char **realname,
	   struct filebuf *fbp)
{
  struct r_search_path_elem **dirs = sps->dirs;
  char *buf;
  int fd = -1;
  const char *current_what = NULL;
  int any = 0;

  buf = alloca (max_dirnamelen + max_capstrlen + namelen);
  do
    {
      struct r_search_path_elem *this_dir = *dirs;
      size_t buflen = 0;
      size_t cnt;
      char *edp;
      int here_any = 0;

      /* If we are debugging the search for libraries print the path
	 now if it hasn't happened now.  */
      if (__builtin_expect (_dl_debug_libs, 0)
	  && current_what != this_dir->what)
	{
	  current_what = this_dir->what;
	  print_search_path (dirs, current_what, this_dir->where);
	}

      edp = (char *) __mempcpy (buf, this_dir->dirname, this_dir->dirnamelen);
      for (cnt = 0; fd == -1 && cnt < ncapstr; ++cnt)
	{
	  /* Skip this directory if we know it does not exist.  */
	  if (this_dir->status[cnt] == nonexisting)
	    continue;

	  buflen =
	    ((char *) __mempcpy (__mempcpy (edp,
					    capstr[cnt].str, capstr[cnt].len),
				 name, namelen)
	     - buf);

	  /* Print name we try if this is wanted.  */
	  if (__builtin_expect (_dl_debug_libs, 0))
	    _dl_debug_message (1, "  trying file=", buf, "\n", NULL);

	  fd = open_verify (buf, fbp);
	  if (this_dir->status[cnt] == unknown)
	    {
	      if (fd != -1)
		this_dir->status[cnt] = existing;
	      else
		{
		  /* We failed to open machine dependent library.  Let's
		     test whether there is any directory at all.  */
		  struct stat64 st;

		  buf[buflen - namelen - 1] = '\0';

		  if (__xstat64 (_STAT_VER, buf, &st) != 0
		      || ! S_ISDIR (st.st_mode))
		    /* The directory does not exist or it is no directory.  */
		    this_dir->status[cnt] = nonexisting;
		  else
		    this_dir->status[cnt] = existing;
		}
	    }

	  /* Remember whether we found any existing directory.  */
	  here_any |= this_dir->status[cnt] == existing;

	  if (fd != -1 && preloaded && __libc_enable_secure)
	    {
	      /* This is an extra security effort to make sure nobody can
		 preload broken shared objects which are in the trusted
		 directories and so exploit the bugs.  */
	      struct stat64 st;

	      if (__fxstat64 (_STAT_VER, fd, &st) != 0
		  || (st.st_mode & S_ISUID) == 0)
		{
		  /* The shared object cannot be tested for being SUID
		     or this bit is not set.  In this case we must not
		     use this object.  */
		  __close (fd);
		  fd = -1;
		  /* We simply ignore the file, signal this by setting
		     the error value which would have been set by `open'.  */
		  errno = ENOENT;
		}
	    }
	}

      if (fd != -1)
	{
	  *realname = malloc (buflen);
	  if (*realname != NULL)
	    {
	      memcpy (*realname, buf, buflen);
	      return fd;
	    }
	  else
	    {
	      /* No memory for the name, we certainly won't be able
		 to load and link it.  */
	      __close (fd);
	      return -1;
	    }
	}
      if (here_any && errno != ENOENT && errno != EACCES)
	/* The file exists and is readable, but something went wrong.  */
	return -1;

      /* Remember whether we found anything.  */
      any |= here_any;
    }
  while (*++dirs != NULL);

  /* Remove the whole path if none of the directories exists.  */
  if (! any)
    {
      /* Paths which were allocated using the minimal malloc() in ld.so
	 must not be freed using the general free() in libc.  */
      if (sps->malloced)
	free (sps->dirs);
      sps->dirs = (void *) -1;
    }

  return -1;
}

/* Map in the shared object file NAME.  */

struct link_map *
internal_function
_dl_map_object (struct link_map *loader, const char *name, int preloaded,
		int type, int trace_mode, int mode)
{
  int fd;
  char *realname;
  char *name_copy;
  struct link_map *l;
  struct filebuf fb;

  /* Look for this name among those already loaded.  */
  for (l = _dl_loaded; l; l = l->l_next)
    {
      /* If the requested name matches the soname of a loaded object,
	 use that object.  Elide this check for names that have not
	 yet been opened.  */
      /* XXX Is this test still correct after the reference counter
	 handling rewrite?  */
      if (l->l_opencount == 0)
	continue;
      if (!_dl_name_match_p (name, l))
	{
	  const char *soname;

	  if (__builtin_expect (l->l_soname_added, 1)
	      || l->l_info[DT_SONAME] == NULL)
	    continue;

	  soname = ((const char *) D_PTR (l, l_info[DT_STRTAB])
		    + l->l_info[DT_SONAME]->d_un.d_val);
	  if (strcmp (name, soname) != 0)
	    continue;

	  /* We have a match on a new name -- cache it.  */
	  add_name_to_object (l, soname);
	  l->l_soname_added = 1;
	}

      /* We have a match.  */
      return l;
    }

  /* Display information if we are debugging.  */
  if (__builtin_expect (_dl_debug_files, 0) && loader != NULL)
    _dl_debug_message (1, "\nfile=", name, ";  needed by ",
		       loader->l_name[0] ? loader->l_name : _dl_argv[0],
		       "\n", NULL);

  if (strchr (name, '/') == NULL)
    {
      /* Search for NAME in several places.  */

      size_t namelen = strlen (name) + 1;

      if (__builtin_expect (_dl_debug_libs, 0))
	_dl_debug_message (1, "find library=", name, "; searching\n", NULL);

      fd = -1;

      /* When the object has the RUNPATH information we don't use any
         RPATHs.  */
      if (loader == NULL || loader->l_info[DT_RUNPATH] == NULL)
	{
	  /* First try the DT_RPATH of the dependent object that caused NAME
	     to be loaded.  Then that object's dependent, and on up.  */
	  for (l = loader; fd == -1 && l; l = l->l_loader)
	    {
	      if (l->l_rpath_dirs.dirs == NULL)
		{
		  if (l->l_info[DT_RPATH] == NULL)
		    /* There is no path.  */
		    l->l_rpath_dirs.dirs = (void *) -1;
		  else
		    {
		      /* Make sure the cache information is available.  */
		      size_t ptrval = (D_PTR (l, l_info[DT_STRTAB])
				       + l->l_info[DT_RPATH]->d_un.d_val);
		      decompose_rpath (&l->l_rpath_dirs,
				       (const char *) ptrval, l, "RPATH");

		      if (l->l_rpath_dirs.dirs != (void *) -1)
			fd = open_path (name, namelen, preloaded,
					&l->l_rpath_dirs, &realname, &fb);
		    }
		}
	      else if (l->l_rpath_dirs.dirs != (void *) -1)
		fd = open_path (name, namelen, preloaded, &l->l_rpath_dirs,
				&realname, &fb);
	    }

	  /* If dynamically linked, try the DT_RPATH of the executable
             itself.  */
	  l = _dl_loaded;
	  if (fd == -1 && l && l->l_type != lt_loaded && l != loader
	      && l->l_rpath_dirs.dirs != (void *) -1)
	    fd = open_path (name, namelen, preloaded, &l->l_rpath_dirs,
			    &realname, &fb);
	}

      /* Try the LD_LIBRARY_PATH environment variable.  */
      if (fd == -1 && env_path_list.dirs != (void *) -1)
	fd = open_path (name, namelen, preloaded, &env_path_list,
			&realname, &fb);

      /* Look at the RUNPATH information for this binary.  */
      if (loader != NULL && loader->l_runpath_dirs.dirs != (void *) -1)
	{
	  if (loader->l_runpath_dirs.dirs == NULL)
	    {
	      if (loader->l_info[DT_RUNPATH] == NULL)
		/* No RUNPATH.  */
		loader->l_runpath_dirs.dirs = (void *) -1;
	      else
		{
		  /* Make sure the cache information is available.  */
		  size_t ptrval = (D_PTR (loader, l_info[DT_STRTAB])
				   + loader->l_info[DT_RUNPATH]->d_un.d_val);
		  decompose_rpath (&loader->l_runpath_dirs,
				   (const char *) ptrval, loader, "RUNPATH");

		  if (loader->l_runpath_dirs.dirs != (void *) -1)
		    fd = open_path (name, namelen, preloaded,
				    &loader->l_runpath_dirs, &realname, &fb);
		}
	    }
	  else if (loader->l_runpath_dirs.dirs != (void *) -1)
	    fd = open_path (name, namelen, preloaded,
			    &loader->l_runpath_dirs, &realname, &fb);
	}

      if (fd == -1 && (! preloaded || ! __libc_enable_secure))
	{
	  /* Check the list of libraries in the file /etc/ld.so.cache,
	     for compatibility with Linux's ldconfig program.  */
	  const char *cached = _dl_load_cache_lookup (name);

#ifdef SHARED
	  l = loader ?: _dl_loaded;
#else
	  l = loader;
#endif

	  if (cached)
	    {
	      /* If the loader has the DF_1_NODEFLIB flag set we must not
		 use a cache entry from any of these directories.  */
	      if (l && __builtin_expect (l->l_flags_1 & DF_1_NODEFLIB, 0))
		{
		  const char *dirp = system_dirs;
		  unsigned int cnt = 0;

		  do
		    {
		      if (memcmp (cached, dirp, system_dirs_len[cnt]) == 0)
			{
			  /* The prefix matches.  Don't use the entry.  */
			  cached = NULL;
			  break;
			}

		      dirp += system_dirs_len[cnt] + 1;
		      ++cnt;
		    }
		  while (cnt < nsystem_dirs_len);
		}

	      if (cached)
		{
		  fd = open_verify (cached, &fb);
		  if (fd != -1)
		    {
		      realname = local_strdup (cached);
		      if (realname == NULL)
			{
			  __close (fd);
			  fd = -1;
			}
		    }
		}
	    }
	}

      /* Finally, try the default path.  */
      if (fd == -1
	  && (l == NULL ||
	      __builtin_expect (!(l->l_flags_1 & DF_1_NODEFLIB), 1))
	  && rtld_search_dirs.dirs != (void *) -1)
	fd = open_path (name, namelen, preloaded, &rtld_search_dirs,
			&realname, &fb);

      /* Add another newline when we a tracing the library loading.  */
      if (__builtin_expect (_dl_debug_libs, 0))
        _dl_debug_message (1, "\n", NULL);
    }
  else
    {
      /* The path may contain dynamic string tokens.  */
      realname = (loader
		  ? expand_dynamic_string_token (loader, name)
		  : local_strdup (name));
      if (realname == NULL)
	fd = -1;
      else
	{
	  fd = open_verify (realname, &fb);
	  if (fd == -1)
	    free (realname);
	}
    }

  if (fd == -1)
    {
      if (trace_mode)
	{
	  /* We haven't found an appropriate library.  But since we
	     are only interested in the list of libraries this isn't
	     so severe.  Fake an entry with all the information we
	     have.  */
	  static const Elf_Symndx dummy_bucket = STN_UNDEF;

	  /* Enter the new object in the list of loaded objects.  */
	  if ((name_copy = local_strdup (name)) == NULL
	      || (l = _dl_new_object (name_copy, name, type, loader)) == NULL)
	    _dl_signal_error (ENOMEM, name,
			      N_("cannot create shared object descriptor"));
	  /* Signal that this is a faked entry.  */
	  l->l_faked = 1;
	  /* Since the descriptor is initialized with zero we do not
	     have do this here.
	  l->l_reserved = 0; */
	  l->l_buckets = &dummy_bucket;
	  l->l_nbuckets = 1;
	  l->l_relocated = 1;

	  return l;
	}
      else
	_dl_signal_error (errno, name, N_("cannot open shared object file"));
    }

  return _dl_map_object_from_fd (name, fd, &fb, realname, loader, type, mode);
}