1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22 /*
23 * Copyright (c) 1988 AT&T
24 * All Rights Reserved
25 *
26 *
27 * Copyright (c) 1989, 2010, Oracle and/or its affiliates. All rights reserved.
28 */
29
30 /*
31 * Symbol table management routines
32 */
33
34 #define ELF_TARGET_AMD64
35
36 #include <stdio.h>
37 #include <string.h>
38 #include <debug.h>
39 #include "msg.h"
40 #include "_libld.h"
41
42 /*
43 * AVL tree comparator function:
44 *
45 * The primary key is the symbol name hash with a secondary key of the symbol
46 * name itself.
47 */
48 int
49 ld_sym_avl_comp(const void *elem1, const void *elem2)
50 {
51 Sym_avlnode *sav1 = (Sym_avlnode *)elem1;
52 Sym_avlnode *sav2 = (Sym_avlnode *)elem2;
53 int res;
54
55 res = sav1->sav_hash - sav2->sav_hash;
56
57 if (res < 0)
58 return (-1);
59 if (res > 0)
60 return (1);
61
62 /*
63 * Hash is equal - now compare name
64 */
65 res = strcmp(sav1->sav_name, sav2->sav_name);
66 if (res == 0)
67 return (0);
68 if (res > 0)
69 return (1);
70 return (-1);
71 }
72
73 /*
74 * Focal point for verifying symbol names.
75 */
76 inline static const char *
77 string(Ofl_desc *ofl, Ifl_desc *ifl, Sym *sym, const char *strs, size_t strsize,
78 int symndx, Word shndx, Word symsecndx, const char *symsecname,
79 const char *strsecname, sd_flag_t *flags)
80 {
81 Word name = sym->st_name;
82
83 if (name) {
84 if ((ifl->ifl_flags & FLG_IF_HSTRTAB) == 0) {
85 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_FIL_NOSTRTABLE),
86 ifl->ifl_name, EC_WORD(symsecndx), symsecname,
87 symndx, EC_XWORD(name));
88 return (NULL);
89 }
90 if (name >= (Word)strsize) {
91 ld_eprintf(ofl, ERR_FATAL,
92 MSG_INTL(MSG_FIL_EXCSTRTABLE), ifl->ifl_name,
93 EC_WORD(symsecndx), symsecname, symndx,
94 EC_XWORD(name), strsecname, EC_XWORD(strsize));
95 return (NULL);
96 }
97 }
98
99 /*
100 * Determine if we're dealing with a register and if so validate it.
101 * If it's a scratch register, a fabricated name will be returned.
102 */
103 if (ld_targ.t_ms.ms_is_regsym != NULL) {
104 const char *regname = (*ld_targ.t_ms.ms_is_regsym)(ofl, ifl,
105 sym, strs, symndx, shndx, symsecname, flags);
106
107 if (regname == (const char *)S_ERROR) {
108 return (NULL);
109 }
110 if (regname)
111 return (regname);
112 }
113
114 /*
115 * If this isn't a register, but we have a global symbol with a null
116 * name, we're not going to be able to hash this, search for it, or
117 * do anything interesting. However, we've been accepting a symbol of
118 * this kind for ages now, so give the user a warning (rather than a
119 * fatal error), just in case this instance exists somewhere in the
120 * world and hasn't, as yet, been a problem.
121 */
122 if ((name == 0) && (ELF_ST_BIND(sym->st_info) != STB_LOCAL)) {
123 ld_eprintf(ofl, ERR_WARNING, MSG_INTL(MSG_FIL_NONAMESYM),
124 ifl->ifl_name, EC_WORD(symsecndx), symsecname, symndx,
125 EC_XWORD(name));
126 }
127 return (strs + name);
128 }
129
130 /*
131 * For producing symbol names strings to use in error messages.
132 * If the symbol has a non-null name, then the string returned by
133 * this function is the output from demangle(), surrounded by
134 * single quotes. For null names, a descriptive string giving
135 * the symbol section and index is generated.
136 *
137 * This function uses an internal static buffer to hold the resulting
138 * string. The value returned is usable by the caller until the next
139 * call, at which point it is overwritten.
140 */
141 static const char *
142 demangle_symname(const char *name, const char *symtab_name, Word symndx)
143 {
144 #define INIT_BUFSIZE 256
145
146 static char *buf;
147 static size_t bufsize = 0;
148 size_t len;
149 int use_name;
150
151 use_name = (name != NULL) && (*name != '\0');
152
153 if (use_name) {
154 name = demangle(name);
155 len = strlen(name) + 2; /* Include room for quotes */
156 } else {
157 name = MSG_ORIG(MSG_STR_EMPTY);
158 len = strlen(symtab_name) + 2 + CONV_INV_BUFSIZE;
159 }
160 len++; /* Null termination */
161
162 /* If our buffer is too small, double it until it is big enough */
163 if (len > bufsize) {
164 size_t new_bufsize = bufsize;
165 char *new_buf;
166
167 if (new_bufsize == 0)
168 new_bufsize = INIT_BUFSIZE;
169 while (len > new_bufsize)
170 new_bufsize *= 2;
171 if ((new_buf = libld_malloc(new_bufsize)) == NULL)
172 return (name);
173 buf = new_buf;
174 bufsize = new_bufsize;
175 }
176
177 if (use_name) {
178 (void) snprintf(buf, bufsize, MSG_ORIG(MSG_FMT_SYMNAM), name);
179 } else {
180 (void) snprintf(buf, bufsize, MSG_ORIG(MSG_FMT_NULLSYMNAM),
181 symtab_name, EC_WORD(symndx));
182 }
183
184 return (buf);
185
186 #undef INIT_BUFSIZE
187 }
188
189 /*
190 * Shared objects can be built that define specific symbols that can not be
191 * directly bound to. These objects have a syminfo section (and an associated
192 * DF_1_NODIRECT dynamic flags entry). Scan this table looking for symbols
193 * that can't be bound to directly, and if this files symbol is presently
194 * referenced, mark it so that we don't directly bind to it.
195 */
196 uintptr_t
197 ld_sym_nodirect(Is_desc *isp, Ifl_desc *ifl, Ofl_desc *ofl)
198 {
199 Shdr *sifshdr, *symshdr;
200 Syminfo *sifdata;
201 Sym *symdata;
202 char *strdata;
203 ulong_t cnt, _cnt;
204
205 /*
206 * Get the syminfo data, and determine the number of entries.
207 */
208 sifshdr = isp->is_shdr;
209 sifdata = (Syminfo *)isp->is_indata->d_buf;
210 cnt = sifshdr->sh_size / sifshdr->sh_entsize;
211
212 /*
213 * Get the associated symbol table.
214 */
215 if ((sifshdr->sh_link == 0) || (sifshdr->sh_link >= ifl->ifl_shnum)) {
216 /*
217 * Broken input file
218 */
219 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_FIL_INVSHINFO),
220 ifl->ifl_name, isp->is_name, EC_XWORD(sifshdr->sh_link));
221 return (0);
222 }
223 symshdr = ifl->ifl_isdesc[sifshdr->sh_link]->is_shdr;
224 symdata = ifl->ifl_isdesc[sifshdr->sh_link]->is_indata->d_buf;
225
226 /*
227 * Get the string table associated with the symbol table.
228 */
229 strdata = ifl->ifl_isdesc[symshdr->sh_link]->is_indata->d_buf;
230
231 /*
232 * Traverse the syminfo data for symbols that can't be directly
233 * bound to.
234 */
235 for (_cnt = 1, sifdata++; _cnt < cnt; _cnt++, sifdata++) {
236 Sym *sym;
237 char *str;
238 Sym_desc *sdp;
239
240 if ((sifdata->si_flags & SYMINFO_FLG_NOEXTDIRECT) == 0)
241 continue;
242
243 sym = (Sym *)(symdata + _cnt);
244 str = (char *)(strdata + sym->st_name);
245
246 if ((sdp = ld_sym_find(str, SYM_NOHASH, NULL, ofl)) != NULL) {
247 if (ifl != sdp->sd_file)
248 continue;
249
250 sdp->sd_flags &= ~FLG_SY_DIR;
251 sdp->sd_flags |= FLG_SY_NDIR;
252 }
253 }
254 return (0);
255 }
256
257 /*
258 * If, during symbol processing, it is necessary to update a local symbols
259 * contents before we have generated the symbol tables in the output image,
260 * create a new symbol structure and copy the original symbol contents. While
261 * we are processing the input files, their local symbols are part of the
262 * read-only mapped image. Commonly, these symbols are copied to the new output
263 * file image and then updated to reflect their new address and any change in
264 * attributes. However, sometimes during relocation counting, it is necessary
265 * to adjust the symbols information. This routine provides for the generation
266 * of a new symbol image so that this update can be performed.
267 * All global symbols are copied to an internal symbol table to improve locality
268 * of reference and hence performance, and thus this copying is not necessary.
269 */
270 uintptr_t
271 ld_sym_copy(Sym_desc *sdp)
272 {
273 Sym *nsym;
274
275 if (sdp->sd_flags & FLG_SY_CLEAN) {
276 if ((nsym = libld_malloc(sizeof (Sym))) == NULL)
277 return (S_ERROR);
278 *nsym = *(sdp->sd_sym);
279 sdp->sd_sym = nsym;
280 sdp->sd_flags &= ~FLG_SY_CLEAN;
281 }
282 return (1);
283 }
284
285 /*
286 * Finds a given name in the link editors internal symbol table. If no
287 * hash value is specified it is calculated. A pointer to the located
288 * Sym_desc entry is returned, or NULL if the symbol is not found.
289 */
290 Sym_desc *
291 ld_sym_find(const char *name, Word hash, avl_index_t *where, Ofl_desc *ofl)
292 {
293 Sym_avlnode qsav, *sav;
294
295 if (hash == SYM_NOHASH)
296 /* LINTED */
297 hash = (Word)elf_hash((const char *)name);
298 qsav.sav_hash = hash;
299 qsav.sav_name = name;
300
301 /*
302 * Perform search for symbol in AVL tree. Note that the 'where' field
303 * is passed in from the caller. If a 'where' is present, it can be
304 * used in subsequent 'ld_sym_enter()' calls if required.
305 */
306 sav = avl_find(&ofl->ofl_symavl, &qsav, where);
307
308 /*
309 * If symbol was not found in the avl tree, return null to show that.
310 */
311 if (sav == NULL)
312 return (NULL);
313
314 /*
315 * Return symbol found.
316 */
317 return (sav->sav_sdp);
318 }
319
320 /*
321 * Enter a new symbol into the link editors internal symbol table.
322 * If the symbol is from an input file, information regarding the input file
323 * and input section is also recorded. Otherwise (file == NULL) the symbol
324 * has been internally generated (ie. _etext, _edata, etc.).
325 */
326 Sym_desc *
327 ld_sym_enter(const char *name, Sym *osym, Word hash, Ifl_desc *ifl,
328 Ofl_desc *ofl, Word ndx, Word shndx, sd_flag_t sdflags, avl_index_t *where)
329 {
330 Sym_desc *sdp;
331 Sym_aux *sap;
332 Sym_avlnode *savl;
333 char *_name;
334 Sym *nsym;
335 Half etype;
336 uchar_t vis;
337 avl_index_t _where;
338
339 /*
340 * Establish the file type.
341 */
342 if (ifl)
343 etype = ifl->ifl_ehdr->e_type;
344 else
345 etype = ET_NONE;
346
347 ofl->ofl_entercnt++;
348
349 /*
350 * Allocate a Sym Descriptor, Auxiliary Descriptor, and a Sym AVLNode -
351 * contiguously.
352 */
353 if ((savl = libld_calloc(S_DROUND(sizeof (Sym_avlnode)) +
354 S_DROUND(sizeof (Sym_desc)) +
355 S_DROUND(sizeof (Sym_aux)), 1)) == NULL)
356 return ((Sym_desc *)S_ERROR);
357 sdp = (Sym_desc *)((uintptr_t)savl +
358 S_DROUND(sizeof (Sym_avlnode)));
359 sap = (Sym_aux *)((uintptr_t)sdp +
360 S_DROUND(sizeof (Sym_desc)));
361
362 savl->sav_sdp = sdp;
363 sdp->sd_file = ifl;
364 sdp->sd_aux = sap;
365 savl->sav_hash = sap->sa_hash = hash;
366
367 /*
368 * Copy the symbol table entry from the input file into the internal
369 * entry and have the symbol descriptor use it.
370 */
371 sdp->sd_sym = nsym = &sap->sa_sym;
372 *nsym = *osym;
373 sdp->sd_shndx = shndx;
374 sdp->sd_flags |= sdflags;
375
376 if ((_name = libld_malloc(strlen(name) + 1)) == NULL)
377 return ((Sym_desc *)S_ERROR);
378 savl->sav_name = sdp->sd_name = (const char *)strcpy(_name, name);
379
380 /*
381 * Enter Symbol in AVL tree.
382 */
383 if (where == 0) {
384 /* LINTED */
385 Sym_avlnode *_savl;
386 /*
387 * If a previous ld_sym_find() hasn't initialized 'where' do it
388 * now.
389 */
390 where = &_where;
391 _savl = avl_find(&ofl->ofl_symavl, savl, where);
392 assert(_savl == NULL);
393 }
394 avl_insert(&ofl->ofl_symavl, savl, *where);
395
396 /*
397 * Record the section index. This is possible because the
398 * `ifl_isdesc' table is filled before we start symbol processing.
399 */
400 if ((sdflags & FLG_SY_SPECSEC) || (nsym->st_shndx == SHN_UNDEF))
401 sdp->sd_isc = NULL;
402 else {
403 sdp->sd_isc = ifl->ifl_isdesc[shndx];
404
405 /*
406 * If this symbol is from a relocatable object, make sure that
407 * it is still associated with a section. For example, an
408 * unknown section type (SHT_NULL) would have been rejected on
409 * input with a warning. Here, we make the use of the symbol
410 * fatal. A symbol descriptor is still returned, so that the
411 * caller can continue processing all symbols, and hence flush
412 * out as many error conditions as possible.
413 */
414 if ((etype == ET_REL) && (sdp->sd_isc == NULL)) {
415 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_SYM_INVSEC),
416 name, ifl->ifl_name, EC_XWORD(shndx));
417 return (sdp);
418 }
419 }
420
421 /*
422 * Mark any COMMON symbols as 'tentative'.
423 */
424 if (sdflags & FLG_SY_SPECSEC) {
425 if (nsym->st_shndx == SHN_COMMON)
426 sdp->sd_flags |= FLG_SY_TENTSYM;
427 #if defined(_ELF64)
428 else if ((ld_targ.t_m.m_mach == EM_AMD64) &&
429 (nsym->st_shndx == SHN_X86_64_LCOMMON))
430 sdp->sd_flags |= FLG_SY_TENTSYM;
431 #endif
432 }
433
434 /*
435 * Establish the symbols visibility and reference.
436 */
437 vis = ELF_ST_VISIBILITY(nsym->st_other);
438
439 if ((etype == ET_NONE) || (etype == ET_REL)) {
440 switch (vis) {
441 case STV_DEFAULT:
442 sdp->sd_flags |= FLG_SY_DEFAULT;
443 break;
444 case STV_INTERNAL:
445 case STV_HIDDEN:
446 sdp->sd_flags |= FLG_SY_HIDDEN;
447 break;
448 case STV_PROTECTED:
449 sdp->sd_flags |= FLG_SY_PROTECT;
450 break;
451 case STV_EXPORTED:
452 sdp->sd_flags |= FLG_SY_EXPORT;
453 break;
454 case STV_SINGLETON:
455 sdp->sd_flags |= (FLG_SY_SINGLE | FLG_SY_NDIR);
456 ofl->ofl_flags1 |= (FLG_OF1_NDIRECT | FLG_OF1_NGLBDIR);
457 break;
458 case STV_ELIMINATE:
459 sdp->sd_flags |= (FLG_SY_HIDDEN | FLG_SY_ELIM);
460 break;
461 default:
462 assert(vis <= STV_ELIMINATE);
463 }
464
465 sdp->sd_ref = REF_REL_NEED;
466
467 /*
468 * Under -Bnodirect, all exported interfaces that have not
469 * explicitly been defined protected or directly bound to, are
470 * tagged to prevent direct binding.
471 */
472 if ((ofl->ofl_flags1 & FLG_OF1_ALNODIR) &&
473 ((sdp->sd_flags & (FLG_SY_PROTECT | FLG_SY_DIR)) == 0) &&
474 (nsym->st_shndx != SHN_UNDEF)) {
475 sdp->sd_flags |= FLG_SY_NDIR;
476 }
477 } else {
478 sdp->sd_ref = REF_DYN_SEEN;
479
480 /*
481 * If this is a protected symbol, remember this. Note, this
482 * state is different from the FLG_SY_PROTECT used to establish
483 * a symbol definitions visibility. This state is used to warn
484 * against possible copy relocations against this referenced
485 * symbol.
486 */
487 if (vis == STV_PROTECTED)
488 sdp->sd_flags |= FLG_SY_PROT;
489
490 /*
491 * If this is a SINGLETON definition, then indicate the symbol
492 * can not be directly bound to, and retain the visibility.
493 * This visibility will be inherited by any references made to
494 * this symbol.
495 */
496 if ((vis == STV_SINGLETON) && (nsym->st_shndx != SHN_UNDEF))
497 sdp->sd_flags |= (FLG_SY_SINGLE | FLG_SY_NDIR);
498
499 /*
500 * If the new symbol is from a shared library and is associated
501 * with a SHT_NOBITS section then this symbol originated from a
502 * tentative symbol.
503 */
504 if (sdp->sd_isc &&
505 (sdp->sd_isc->is_shdr->sh_type == SHT_NOBITS))
506 sdp->sd_flags |= FLG_SY_TENTSYM;
507 }
508
509 /*
510 * Reclassify any SHN_SUNW_IGNORE symbols to SHN_UNDEF so as to
511 * simplify future processing.
512 */
513 if (nsym->st_shndx == SHN_SUNW_IGNORE) {
514 sdp->sd_shndx = shndx = SHN_UNDEF;
515 sdp->sd_flags |= (FLG_SY_REDUCED |
516 FLG_SY_HIDDEN | FLG_SY_IGNORE | FLG_SY_ELIM);
517 }
518
519 /*
520 * If this is an undefined, or common symbol from a relocatable object
521 * determine whether it is a global or weak reference (see build_osym(),
522 * where REF_DYN_NEED definitions are returned back to undefines).
523 */
524 if ((etype == ET_REL) &&
525 (ELF_ST_BIND(nsym->st_info) == STB_GLOBAL) &&
526 ((nsym->st_shndx == SHN_UNDEF) || ((sdflags & FLG_SY_SPECSEC) &&
527 #if defined(_ELF64)
528 ((nsym->st_shndx == SHN_COMMON) ||
529 ((ld_targ.t_m.m_mach == EM_AMD64) &&
530 (nsym->st_shndx == SHN_X86_64_LCOMMON))))))
531 #else
532 /* BEGIN CSTYLED */
533 (nsym->st_shndx == SHN_COMMON))))
534 /* END CSTYLED */
535 #endif
536 sdp->sd_flags |= FLG_SY_GLOBREF;
537
538 /*
539 * Record the input filename on the referenced or defined files list
540 * for possible later diagnostics. The `sa_rfile' pointer contains the
541 * name of the file that first referenced this symbol and is used to
542 * generate undefined symbol diagnostics (refer to sym_undef_entry()).
543 * Note that this entry can be overridden if a reference from a
544 * relocatable object is found after a reference from a shared object
545 * (refer to sym_override()).
546 * The `sa_dfiles' list is used to maintain the list of files that
547 * define the same symbol. This list can be used for two reasons:
548 *
549 * - To save the first definition of a symbol that is not available
550 * for this link-edit.
551 *
552 * - To save all definitions of a symbol when the -m option is in
553 * effect. This is optional as it is used to list multiple
554 * (interposed) definitions of a symbol (refer to ldmap_out()),
555 * and can be quite expensive.
556 */
557 if (nsym->st_shndx == SHN_UNDEF) {
558 sap->sa_rfile = ifl->ifl_name;
559 } else {
560 if (sdp->sd_ref == REF_DYN_SEEN) {
561 /*
562 * A symbol is determined to be unavailable if it
563 * belongs to a version of a shared object that this
564 * user does not wish to use, or if it belongs to an
565 * implicit shared object.
566 */
567 if (ifl->ifl_vercnt) {
568 Ver_index *vip;
569 Half vndx = ifl->ifl_versym[ndx];
570
571 sap->sa_dverndx = vndx;
572 vip = &ifl->ifl_verndx[vndx];
573 if (!(vip->vi_flags & FLG_VER_AVAIL)) {
574 sdp->sd_flags |= FLG_SY_NOTAVAIL;
575 sap->sa_vfile = ifl->ifl_name;
576 }
577 }
578 if (!(ifl->ifl_flags & FLG_IF_NEEDED))
579 sdp->sd_flags |= FLG_SY_NOTAVAIL;
580
581 } else if (etype == ET_REL) {
582 /*
583 * If this symbol has been obtained from a versioned
584 * input relocatable object then the new symbol must be
585 * promoted to the versioning of the output file.
586 */
587 if (ifl->ifl_versym)
588 ld_vers_promote(sdp, ndx, ifl, ofl);
589 }
590
591 if ((ofl->ofl_flags & FLG_OF_GENMAP) &&
592 ((sdflags & FLG_SY_SPECSEC) == 0))
593 if (aplist_append(&sap->sa_dfiles, ifl->ifl_name,
594 AL_CNT_SDP_DFILES) == NULL)
595 return ((Sym_desc *)S_ERROR);
596 }
597
598 /*
599 * Provided we're not processing a mapfile, diagnose the entered symbol.
600 * Mapfile processing requires the symbol to be updated with additional
601 * information, therefore the diagnosing of the symbol is deferred until
602 * later (see Dbg_map_symbol()).
603 */
604 if ((ifl == NULL) || ((ifl->ifl_flags & FLG_IF_MAPFILE) == 0))
605 DBG_CALL(Dbg_syms_entered(ofl, nsym, sdp));
606
607 return (sdp);
608 }
609
610 /*
611 * Add a special symbol to the symbol table. Takes special symbol name with
612 * and without underscores. This routine is called, after all other symbol
613 * resolution has completed, to generate a reserved absolute symbol (the
614 * underscore version). Special symbols are updated with the appropriate
615 * values in update_osym(). If the user has already defined this symbol
616 * issue a warning and leave the symbol as is. If the non-underscore symbol
617 * is referenced then turn it into a weak alias of the underscored symbol.
618 *
619 * The bits in sdflags_u are OR'd into the flags field of the symbol for the
620 * underscored symbol.
621 *
622 * If this is a global symbol, and it hasn't explicitly been defined as being
623 * directly bound to, indicate that it can't be directly bound to.
624 * Historically, most special symbols only have meaning to the object in which
625 * they exist, however, they've always been global. To ensure compatibility
626 * with any unexpected use presently in effect, ensure these symbols don't get
627 * directly bound to. Note, that establishing this state here isn't sufficient
628 * to create a syminfo table, only if a syminfo table is being created by some
629 * other symbol directives will the nodirect binding be recorded. This ensures
630 * we don't create syminfo sections for all objects we create, as this might add
631 * unnecessary bloat to users who haven't explicitly requested extra symbol
632 * information.
633 */
634 static uintptr_t
635 sym_add_spec(const char *name, const char *uname, Word sdaux_id,
636 sd_flag_t sdflags_u, sd_flag_t sdflags, Ofl_desc *ofl)
637 {
638 Sym_desc *sdp;
639 Sym_desc *usdp;
640 Sym *sym;
641 Word hash;
642 avl_index_t where;
643
644 /* LINTED */
645 hash = (Word)elf_hash(uname);
646 if (usdp = ld_sym_find(uname, hash, &where, ofl)) {
647 /*
648 * If the underscore symbol exists and is undefined, or was
649 * defined in a shared library, convert it to a local symbol.
650 * Otherwise leave it as is and warn the user.
651 */
652 if ((usdp->sd_shndx == SHN_UNDEF) ||
653 (usdp->sd_ref != REF_REL_NEED)) {
654 usdp->sd_ref = REF_REL_NEED;
655 usdp->sd_shndx = usdp->sd_sym->st_shndx = SHN_ABS;
656 usdp->sd_flags |= FLG_SY_SPECSEC | sdflags_u;
657 usdp->sd_sym->st_info =
658 ELF_ST_INFO(STB_GLOBAL, STT_OBJECT);
659 usdp->sd_isc = NULL;
660 usdp->sd_sym->st_size = 0;
661 usdp->sd_sym->st_value = 0;
662 /* LINTED */
663 usdp->sd_aux->sa_symspec = (Half)sdaux_id;
664
665 /*
666 * If a user hasn't specifically indicated that the
667 * scope of this symbol be made local, then leave it
668 * as global (ie. prevent automatic scoping). The GOT
669 * should be defined protected, whereas all other
670 * special symbols are tagged as no-direct.
671 */
672 if (!SYM_IS_HIDDEN(usdp) &&
673 (sdflags & FLG_SY_DEFAULT)) {
674 usdp->sd_aux->sa_overndx = VER_NDX_GLOBAL;
675 if (sdaux_id == SDAUX_ID_GOT) {
676 usdp->sd_flags &= ~FLG_SY_NDIR;
677 usdp->sd_flags |= FLG_SY_PROTECT;
678 usdp->sd_sym->st_other = STV_PROTECTED;
679 } else if (
680 ((usdp->sd_flags & FLG_SY_DIR) == 0) &&
681 ((ofl->ofl_flags & FLG_OF_SYMBOLIC) == 0)) {
682 usdp->sd_flags |= FLG_SY_NDIR;
683 }
684 }
685 usdp->sd_flags |= sdflags;
686
687 /*
688 * If the reference originated from a mapfile ensure
689 * we mark the symbol as used.
690 */
691 if (usdp->sd_flags & FLG_SY_MAPREF)
692 usdp->sd_flags |= FLG_SY_MAPUSED;
693
694 DBG_CALL(Dbg_syms_updated(ofl, usdp, uname));
695 } else
696 ld_eprintf(ofl, ERR_WARNING, MSG_INTL(MSG_SYM_RESERVE),
697 uname, usdp->sd_file->ifl_name);
698 } else {
699 /*
700 * If the symbol does not exist create it.
701 */
702 if ((sym = libld_calloc(sizeof (Sym), 1)) == NULL)
703 return (S_ERROR);
704 sym->st_shndx = SHN_ABS;
705 sym->st_info = ELF_ST_INFO(STB_GLOBAL, STT_OBJECT);
706 sym->st_size = 0;
707 sym->st_value = 0;
708 DBG_CALL(Dbg_syms_created(ofl->ofl_lml, uname));
709 if ((usdp = ld_sym_enter(uname, sym, hash, (Ifl_desc *)NULL,
710 ofl, 0, SHN_ABS, (FLG_SY_SPECSEC | sdflags_u), &where)) ==
711 (Sym_desc *)S_ERROR)
712 return (S_ERROR);
713 usdp->sd_ref = REF_REL_NEED;
714 /* LINTED */
715 usdp->sd_aux->sa_symspec = (Half)sdaux_id;
716
717 usdp->sd_aux->sa_overndx = VER_NDX_GLOBAL;
718
719 if (sdaux_id == SDAUX_ID_GOT) {
720 usdp->sd_flags |= FLG_SY_PROTECT;
721 usdp->sd_sym->st_other = STV_PROTECTED;
722 } else if ((sdflags & FLG_SY_DEFAULT) &&
723 ((ofl->ofl_flags & FLG_OF_SYMBOLIC) == 0)) {
724 usdp->sd_flags |= FLG_SY_NDIR;
725 }
726 usdp->sd_flags |= sdflags;
727 }
728
729 if (name && (sdp = ld_sym_find(name, SYM_NOHASH, NULL, ofl)) &&
730 (sdp->sd_sym->st_shndx == SHN_UNDEF)) {
731 uchar_t bind;
732
733 /*
734 * If the non-underscore symbol exists and is undefined
735 * convert it to be a local. If the underscore has
736 * sa_symspec set (ie. it was created above) then simulate this
737 * as a weak alias.
738 */
739 sdp->sd_ref = REF_REL_NEED;
740 sdp->sd_shndx = sdp->sd_sym->st_shndx = SHN_ABS;
741 sdp->sd_flags |= FLG_SY_SPECSEC;
742 sdp->sd_isc = NULL;
743 sdp->sd_sym->st_size = 0;
744 sdp->sd_sym->st_value = 0;
745 /* LINTED */
746 sdp->sd_aux->sa_symspec = (Half)sdaux_id;
747 if (usdp->sd_aux->sa_symspec) {
748 usdp->sd_aux->sa_linkndx = 0;
749 sdp->sd_aux->sa_linkndx = 0;
750 bind = STB_WEAK;
751 } else
752 bind = STB_GLOBAL;
753 sdp->sd_sym->st_info = ELF_ST_INFO(bind, STT_OBJECT);
754
755 /*
756 * If a user hasn't specifically indicated the scope of this
757 * symbol be made local then leave it as global (ie. prevent
758 * automatic scoping). The GOT should be defined protected,
759 * whereas all other special symbols are tagged as no-direct.
760 */
761 if (!SYM_IS_HIDDEN(sdp) &&
762 (sdflags & FLG_SY_DEFAULT)) {
763 sdp->sd_aux->sa_overndx = VER_NDX_GLOBAL;
764 if (sdaux_id == SDAUX_ID_GOT) {
765 sdp->sd_flags &= ~FLG_SY_NDIR;
766 sdp->sd_flags |= FLG_SY_PROTECT;
767 sdp->sd_sym->st_other = STV_PROTECTED;
768 } else if (((sdp->sd_flags & FLG_SY_DIR) == 0) &&
769 ((ofl->ofl_flags & FLG_OF_SYMBOLIC) == 0)) {
770 sdp->sd_flags |= FLG_SY_NDIR;
771 }
772 }
773 sdp->sd_flags |= sdflags;
774
775 /*
776 * If the reference originated from a mapfile ensure
777 * we mark the symbol as used.
778 */
779 if (sdp->sd_flags & FLG_SY_MAPREF)
780 sdp->sd_flags |= FLG_SY_MAPUSED;
781
782 DBG_CALL(Dbg_syms_updated(ofl, sdp, name));
783 }
784 return (1);
785 }
786
787
788 /*
789 * Undefined symbols can fall into one of four types:
790 *
791 * - the symbol is really undefined (SHN_UNDEF).
792 *
793 * - versioning has been enabled, however this symbol has not been assigned
794 * to one of the defined versions.
795 *
796 * - the symbol has been defined by an implicitly supplied library, ie. one
797 * which was encounted because it was NEEDED by another library, rather
798 * than from a command line supplied library which would become the only
799 * dependency of the output file being produced.
800 *
801 * - the symbol has been defined by a version of a shared object that is
802 * not permitted for this link-edit.
803 *
804 * In all cases the file who made the first reference to this symbol will have
805 * been recorded via the `sa_rfile' pointer.
806 */
807 typedef enum {
808 UNDEF, NOVERSION, IMPLICIT, NOTAVAIL,
809 BNDLOCAL
810 } Type;
811
812 static const Msg format[] = {
813 MSG_SYM_UND_UNDEF, /* MSG_INTL(MSG_SYM_UND_UNDEF) */
814 MSG_SYM_UND_NOVER, /* MSG_INTL(MSG_SYM_UND_NOVER) */
815 MSG_SYM_UND_IMPL, /* MSG_INTL(MSG_SYM_UND_IMPL) */
816 MSG_SYM_UND_NOTA, /* MSG_INTL(MSG_SYM_UND_NOTA) */
817 MSG_SYM_UND_BNDLOCAL /* MSG_INTL(MSG_SYM_UND_BNDLOCAL) */
818 };
819
820 /*
821 * Issue an undefined symbol message for the given symbol.
822 *
823 * entry:
824 * ofl - Output descriptor
825 * sdp - Undefined symbol to report
826 * type - Type of undefined symbol
827 * ofl_flag - One of 0, FLG_OF_FATAL, or FLG_OF_WARN.
828 * undef_state - Address of variable to be initialized to 0
829 * before the first call to sym_undef_entry, and passed
830 * to each subsequent call. A non-zero value for *undef_state
831 * indicates that this is not the first call in the series.
832 *
833 * exit:
834 * If *undef_state is 0, a title is issued.
835 *
836 * A message for the undefined symbol is issued.
837 *
838 * If ofl_flag is non-zero, its value is OR'd into *undef_state. Otherwise,
839 * all bits other than FLG_OF_FATAL and FLG_OF_WARN are set, in order to
840 * provide *undef_state with a non-zero value. These other bits have
841 * no meaning beyond that, and serve to ensure that *undef_state is
842 * non-zero if sym_undef_entry() has been called.
843 */
844 static void
845 sym_undef_entry(Ofl_desc *ofl, Sym_desc *sdp, Type type, ofl_flag_t ofl_flag,
846 ofl_flag_t *undef_state)
847 {
848 const char *name1, *name2, *name3;
849 Ifl_desc *ifl = sdp->sd_file;
850 Sym_aux *sap = sdp->sd_aux;
851
852 if (*undef_state == 0)
853 ld_eprintf(ofl, ERR_NONE, MSG_INTL(MSG_SYM_FMT_UNDEF),
854 MSG_INTL(MSG_SYM_UNDEF_ITM_11),
855 MSG_INTL(MSG_SYM_UNDEF_ITM_21),
856 MSG_INTL(MSG_SYM_UNDEF_ITM_12),
857 MSG_INTL(MSG_SYM_UNDEF_ITM_22));
858
859 ofl->ofl_flags |= ofl_flag;
860 *undef_state |= ofl_flag ? ofl_flag : ~(FLG_OF_FATAL | FLG_OF_WARN);
861
862 switch (type) {
863 case UNDEF:
864 case BNDLOCAL:
865 name1 = sap->sa_rfile;
866 break;
867 case NOVERSION:
868 name1 = ifl->ifl_name;
869 break;
870 case IMPLICIT:
871 name1 = sap->sa_rfile;
872 name2 = ifl->ifl_name;
873 break;
874 case NOTAVAIL:
875 name1 = sap->sa_rfile;
876 name2 = sap->sa_vfile;
877 name3 = ifl->ifl_verndx[sap->sa_dverndx].vi_name;
878 break;
879 default:
880 return;
881 }
882
883 ld_eprintf(ofl, ERR_NONE, MSG_INTL(format[type]),
884 demangle(sdp->sd_name), name1, name2, name3);
885 }
886
887 /*
888 * At this point all symbol input processing has been completed, therefore
889 * complete the symbol table entries by generating any necessary internal
890 * symbols.
891 */
892 uintptr_t
893 ld_sym_spec(Ofl_desc *ofl)
894 {
895 Sym_desc *sdp;
896
897 if (ofl->ofl_flags & FLG_OF_RELOBJ)
898 return (1);
899
900 DBG_CALL(Dbg_syms_spec_title(ofl->ofl_lml));
901
902 if (sym_add_spec(MSG_ORIG(MSG_SYM_ETEXT), MSG_ORIG(MSG_SYM_ETEXT_U),
903 SDAUX_ID_ETEXT, 0, (FLG_SY_DEFAULT | FLG_SY_EXPDEF),
904 ofl) == S_ERROR)
905 return (S_ERROR);
906 if (sym_add_spec(MSG_ORIG(MSG_SYM_EDATA), MSG_ORIG(MSG_SYM_EDATA_U),
907 SDAUX_ID_EDATA, 0, (FLG_SY_DEFAULT | FLG_SY_EXPDEF),
908 ofl) == S_ERROR)
909 return (S_ERROR);
910 if (sym_add_spec(MSG_ORIG(MSG_SYM_END), MSG_ORIG(MSG_SYM_END_U),
911 SDAUX_ID_END, FLG_SY_DYNSORT, (FLG_SY_DEFAULT | FLG_SY_EXPDEF),
912 ofl) == S_ERROR)
913 return (S_ERROR);
914 if (sym_add_spec(MSG_ORIG(MSG_SYM_L_END), MSG_ORIG(MSG_SYM_L_END_U),
915 SDAUX_ID_END, 0, FLG_SY_HIDDEN, ofl) == S_ERROR)
916 return (S_ERROR);
917 if (sym_add_spec(MSG_ORIG(MSG_SYM_L_START), MSG_ORIG(MSG_SYM_L_START_U),
918 SDAUX_ID_START, 0, FLG_SY_HIDDEN, ofl) == S_ERROR)
919 return (S_ERROR);
920
921 /*
922 * Historically we've always produced a _DYNAMIC symbol, even for
923 * static executables (in which case its value will be 0).
924 */
925 if (sym_add_spec(MSG_ORIG(MSG_SYM_DYNAMIC), MSG_ORIG(MSG_SYM_DYNAMIC_U),
926 SDAUX_ID_DYN, FLG_SY_DYNSORT, (FLG_SY_DEFAULT | FLG_SY_EXPDEF),
927 ofl) == S_ERROR)
928 return (S_ERROR);
929
930 if (OFL_ALLOW_DYNSYM(ofl))
931 if (sym_add_spec(MSG_ORIG(MSG_SYM_PLKTBL),
932 MSG_ORIG(MSG_SYM_PLKTBL_U), SDAUX_ID_PLT,
933 FLG_SY_DYNSORT, (FLG_SY_DEFAULT | FLG_SY_EXPDEF),
934 ofl) == S_ERROR)
935 return (S_ERROR);
936
937 /*
938 * A GOT reference will be accompanied by the associated GOT symbol.
939 * Make sure it gets assigned the appropriate special attributes.
940 */
941 if (((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_GOFTBL_U),
942 SYM_NOHASH, NULL, ofl)) != NULL) && (sdp->sd_ref != REF_DYN_SEEN)) {
943 if (sym_add_spec(MSG_ORIG(MSG_SYM_GOFTBL),
944 MSG_ORIG(MSG_SYM_GOFTBL_U), SDAUX_ID_GOT, FLG_SY_DYNSORT,
945 (FLG_SY_DEFAULT | FLG_SY_EXPDEF), ofl) == S_ERROR)
946 return (S_ERROR);
947 }
948
949 return (1);
950 }
951
952 /*
953 * Determine a potential capability symbol's visibility.
954 *
955 * The -z symbolcap option transforms an object capabilities relocatable object
956 * into a symbol capabilities relocatable object. Any global function symbols,
957 * or initialized global data symbols are candidates for transforming into local
958 * symbol capabilities definitions. However, if a user indicates that a symbol
959 * should be demoted to local using a mapfile, then there is no need to
960 * transform the associated global symbol.
961 *
962 * Normally, a symbol's visibility is determined after the symbol resolution
963 * process, after all symbol state has been gathered and resolved. However,
964 * for -z symbolcap, this determination is too late. When a global symbol is
965 * read from an input file we need to determine it's visibility so as to decide
966 * whether to create a local or not.
967 *
968 * If a user has explicitly defined this symbol as having local scope within a
969 * mapfile, then a symbol of the same name already exists. However, explicit
970 * local definitions are uncommon, as most mapfiles define the global symbol
971 * requirements together with an auto-reduction directive '*'. If this state
972 * has been defined, then we must make sure that the new symbol isn't a type
973 * that can not be demoted to local.
974 */
975 static int
976 sym_cap_vis(const char *name, Word hash, Sym *sym, Ofl_desc *ofl)
977 {
978 Sym_desc *sdp;
979 uchar_t vis;
980 avl_index_t where;
981 sd_flag_t sdflags = 0;
982
983 /*
984 * Determine the visibility of the new symbol.
985 */
986 vis = ELF_ST_VISIBILITY(sym->st_other);
987 switch (vis) {
988 case STV_EXPORTED:
989 sdflags |= FLG_SY_EXPORT;
990 break;
991 case STV_SINGLETON:
992 sdflags |= FLG_SY_SINGLE;
993 break;
994 case STV_HIDDEN:
995 sdflags |= FLG_SY_HIDDEN;
996 break;
997 }
998
999 /*
1000 * Determine whether a symbol definition already exists, and if so
1001 * obtain the visibility.
1002 */
1003 if ((sdp = ld_sym_find(name, hash, &where, ofl)) != NULL)
1004 sdflags |= sdp->sd_flags;
1005
1006 /*
1007 * Determine whether the symbol flags indicate this symbol should be
1008 * hidden.
1009 */
1010 if ((ofl->ofl_flags & (FLG_OF_AUTOLCL | FLG_OF_AUTOELM)) &&
1011 ((sdflags & MSK_SY_NOAUTO) == 0))
1012 sdflags |= FLG_SY_HIDDEN;
1013
1014 return ((sdflags & FLG_SY_HIDDEN) == 0);
1015 }
1016
1017 /*
1018 * This routine checks to see if a symbols visibility needs to be reduced to
1019 * either SYMBOLIC or LOCAL. This routine can be called from either
1020 * reloc_init() or sym_validate().
1021 */
1022 void
1023 ld_sym_adjust_vis(Sym_desc *sdp, Ofl_desc *ofl)
1024 {
1025 ofl_flag_t oflags = ofl->ofl_flags;
1026 Sym *sym = sdp->sd_sym;
1027
1028 if ((sdp->sd_ref == REF_REL_NEED) &&
1029 (sdp->sd_sym->st_shndx != SHN_UNDEF)) {
1030 /*
1031 * If auto-reduction/elimination is enabled, reduce any
1032 * non-versioned, and non-local capabilities global symbols.
1033 * A symbol is a candidate for auto-reduction/elimination if:
1034 *
1035 * - the symbol wasn't explicitly defined within a mapfile
1036 * (in which case all the necessary state has been applied
1037 * to the symbol), or
1038 * - the symbol isn't one of the family of reserved
1039 * special symbols (ie. _end, _etext, etc.), or
1040 * - the symbol isn't a SINGLETON, or
1041 * - the symbol wasn't explicitly defined within a version
1042 * definition associated with an input relocatable object.
1043 *
1044 * Indicate that the symbol has been reduced as it may be
1045 * necessary to print these symbols later.
1046 */
1047 if ((oflags & (FLG_OF_AUTOLCL | FLG_OF_AUTOELM)) &&
1048 ((sdp->sd_flags & MSK_SY_NOAUTO) == 0)) {
1049 if ((sdp->sd_flags & FLG_SY_HIDDEN) == 0) {
1050 sdp->sd_flags |=
1051 (FLG_SY_REDUCED | FLG_SY_HIDDEN);
1052 }
1053
1054 if (oflags & (FLG_OF_REDLSYM | FLG_OF_AUTOELM)) {
1055 sdp->sd_flags |= FLG_SY_ELIM;
1056 sym->st_other = STV_ELIMINATE |
1057 (sym->st_other & ~MSK_SYM_VISIBILITY);
1058 } else if (ELF_ST_VISIBILITY(sym->st_other) !=
1059 STV_INTERNAL)
1060 sym->st_other = STV_HIDDEN |
1061 (sym->st_other & ~MSK_SYM_VISIBILITY);
1062 }
1063
1064 /*
1065 * If -Bsymbolic is in effect, and the symbol hasn't explicitly
1066 * been defined nodirect (via a mapfile), then bind the global
1067 * symbol symbolically and assign the STV_PROTECTED visibility
1068 * attribute.
1069 */
1070 if ((oflags & FLG_OF_SYMBOLIC) &&
1071 ((sdp->sd_flags & (FLG_SY_HIDDEN | FLG_SY_NDIR)) == 0)) {
1072 sdp->sd_flags |= FLG_SY_PROTECT;
1073 if (ELF_ST_VISIBILITY(sym->st_other) == STV_DEFAULT)
1074 sym->st_other = STV_PROTECTED |
1075 (sym->st_other & ~MSK_SYM_VISIBILITY);
1076 }
1077 }
1078
1079 /*
1080 * Indicate that this symbol has had it's visibility checked so that
1081 * we don't need to do this investigation again.
1082 */
1083 sdp->sd_flags |= FLG_SY_VISIBLE;
1084 }
1085
1086 /*
1087 * Make sure a symbol definition is local to the object being built.
1088 */
1089 inline static int
1090 ensure_sym_local(Ofl_desc *ofl, Sym_desc *sdp, const char *str)
1091 {
1092 if (sdp->sd_sym->st_shndx == SHN_UNDEF) {
1093 if (str) {
1094 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_SYM_UNDEF),
1095 str, demangle((char *)sdp->sd_name));
1096 }
1097 return (1);
1098 }
1099 if (sdp->sd_ref != REF_REL_NEED) {
1100 if (str) {
1101 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_SYM_EXTERN),
1102 str, demangle((char *)sdp->sd_name),
1103 sdp->sd_file->ifl_name);
1104 }
1105 return (1);
1106 }
1107
1108 sdp->sd_flags |= FLG_SY_UPREQD;
1109 if (sdp->sd_isc) {
1110 sdp->sd_isc->is_flags |= FLG_IS_SECTREF;
1111 sdp->sd_isc->is_file->ifl_flags |= FLG_IF_FILEREF;
1112 }
1113 return (0);
1114 }
1115
1116 /*
1117 * Make sure all the symbol definitions required for initarray, finiarray, or
1118 * preinitarray's are local to the object being built.
1119 */
1120 static int
1121 ensure_array_local(Ofl_desc *ofl, APlist *apl, const char *str)
1122 {
1123 Aliste idx;
1124 Sym_desc *sdp;
1125 int ret = 0;
1126
1127 for (APLIST_TRAVERSE(apl, idx, sdp))
1128 ret += ensure_sym_local(ofl, sdp, str);
1129
1130 return (ret);
1131 }
1132
1133 /*
1134 * After all symbol table input processing has been finished, and all relocation
1135 * counting has been carried out (ie. no more symbols will be read, generated,
1136 * or modified), validate and count the relevant entries:
1137 *
1138 * - check and print any undefined symbols remaining. Note that if a symbol
1139 * has been defined by virtue of the inclusion of an implicit shared
1140 * library, it is still classed as undefined.
1141 *
1142 * - count the number of global needed symbols together with the size of
1143 * their associated name strings (if scoping has been indicated these
1144 * symbols may be reduced to locals).
1145 *
1146 * - establish the size and alignment requirements for the global .bss
1147 * section (the alignment of this section is based on the first symbol
1148 * that it will contain).
1149 */
1150 uintptr_t
1151 ld_sym_validate(Ofl_desc *ofl)
1152 {
1153 Sym_avlnode *sav;
1154 Sym_desc *sdp;
1155 Sym *sym;
1156 ofl_flag_t oflags = ofl->ofl_flags;
1157 ofl_flag_t undef = 0, needed = 0, verdesc = 0;
1158 Xword bssalign = 0, tlsalign = 0;
1159 Boolean need_bss, need_tlsbss;
1160 Xword bsssize = 0, tlssize = 0;
1161 #if defined(_ELF64)
1162 Xword lbssalign = 0, lbsssize = 0;
1163 Boolean need_lbss;
1164 #endif
1165 int ret, allow_ldynsym;
1166 uchar_t type;
1167 ofl_flag_t undef_state = 0;
1168
1169 DBG_CALL(Dbg_basic_validate(ofl->ofl_lml));
1170
1171 /*
1172 * The need_XXX booleans are used to determine whether we need to
1173 * create each type of bss section. We used to create these sections
1174 * if the sum of the required sizes for each type were non-zero.
1175 * However, it is possible for a compiler to generate COMMON variables
1176 * of zero-length and this tricks that logic --- even zero-length
1177 * symbols need an output section.
1178 */
1179 need_bss = need_tlsbss = FALSE;
1180 #if defined(_ELF64)
1181 need_lbss = FALSE;
1182 #endif
1183
1184 /*
1185 * Determine how undefined symbols are handled:
1186 *
1187 * fatal:
1188 * If this link-edit calls for no undefined symbols to remain
1189 * (this is the default case when generating an executable but
1190 * can be enforced for any object using -z defs), a fatal error
1191 * condition will be indicated.
1192 *
1193 * warning:
1194 * If we're creating a shared object, and either the -Bsymbolic
1195 * flag is set, or the user has turned on the -z guidance feature,
1196 * then a non-fatal warning is issued for each symbol.
1197 *
1198 * ignore:
1199 * In all other cases, undefined symbols are quietly allowed.
1200 */
1201 if (oflags & FLG_OF_NOUNDEF) {
1202 undef = FLG_OF_FATAL;
1203 } else if (oflags & FLG_OF_SHAROBJ) {
1204 if ((oflags & FLG_OF_SYMBOLIC) ||
1205 OFL_GUIDANCE(ofl, FLG_OFG_NO_DEFS))
1206 undef = FLG_OF_WARN;
1207 }
1208
1209 /*
1210 * If the symbol is referenced from an implicitly included shared object
1211 * (ie. it's not on the NEEDED list) then the symbol is also classified
1212 * as undefined and a fatal error condition will be indicated.
1213 */
1214 if ((oflags & FLG_OF_NOUNDEF) || !(oflags & FLG_OF_SHAROBJ))
1215 needed = FLG_OF_FATAL;
1216 else if ((oflags & FLG_OF_SHAROBJ) &&
1217 OFL_GUIDANCE(ofl, FLG_OFG_NO_DEFS))
1218 needed = FLG_OF_WARN;
1219
1220 /*
1221 * If the output image is being versioned, then all symbol definitions
1222 * must be associated with a version. Any symbol that isn't associated
1223 * with a version is classified as undefined, and a fatal error
1224 * condition is indicated.
1225 */
1226 if ((oflags & FLG_OF_VERDEF) && (ofl->ofl_vercnt > VER_NDX_GLOBAL))
1227 verdesc = FLG_OF_FATAL;
1228
1229 allow_ldynsym = OFL_ALLOW_LDYNSYM(ofl);
1230
1231 if (allow_ldynsym) {
1232 /*
1233 * Normally, we disallow symbols with 0 size from appearing
1234 * in a dyn[sym|tls]sort section. However, there are some
1235 * symbols that serve special purposes that we want to exempt
1236 * from this rule. Look them up, and set their
1237 * FLG_SY_DYNSORT flag.
1238 */
1239 static const char *special[] = {
1240 MSG_ORIG(MSG_SYM_INIT_U), /* _init */
1241 MSG_ORIG(MSG_SYM_FINI_U), /* _fini */
1242 MSG_ORIG(MSG_SYM_START), /* _start */
1243 NULL
1244 };
1245 int i;
1246
1247 for (i = 0; special[i] != NULL; i++) {
1248 if (((sdp = ld_sym_find(special[i],
1249 SYM_NOHASH, NULL, ofl)) != NULL) &&
1250 (sdp->sd_sym->st_size == 0)) {
1251 if (ld_sym_copy(sdp) == S_ERROR)
1252 return (S_ERROR);
1253 sdp->sd_flags |= FLG_SY_DYNSORT;
1254 }
1255 }
1256 }
1257
1258 /*
1259 * Collect and validate the globals from the internal symbol table.
1260 */
1261 for (sav = avl_first(&ofl->ofl_symavl); sav;
1262 sav = AVL_NEXT(&ofl->ofl_symavl, sav)) {
1263 Is_desc *isp;
1264 int undeferr = 0;
1265 uchar_t vis;
1266
1267 sdp = sav->sav_sdp;
1268
1269 /*
1270 * If undefined symbols are allowed, and we're not being
1271 * asked to supply guidance, ignore any symbols that are
1272 * not needed.
1273 */
1274 if (!(oflags & FLG_OF_NOUNDEF) &&
1275 !OFL_GUIDANCE(ofl, FLG_OFG_NO_DEFS) &&
1276 (sdp->sd_ref == REF_DYN_SEEN))
1277 continue;
1278
1279 /*
1280 * If the symbol originates from an external or parent mapfile
1281 * reference and hasn't been matched to a reference from a
1282 * relocatable object, ignore it.
1283 */
1284 if ((sdp->sd_flags & (FLG_SY_EXTERN | FLG_SY_PARENT)) &&
1285 ((sdp->sd_flags & FLG_SY_MAPUSED) == 0)) {
1286 sdp->sd_flags |= FLG_SY_INVALID;
1287 continue;
1288 }
1289
1290 sym = sdp->sd_sym;
1291 type = ELF_ST_TYPE(sym->st_info);
1292
1293 /*
1294 * Sanity check TLS.
1295 */
1296 if ((type == STT_TLS) && (sym->st_size != 0) &&
1297 (sym->st_shndx != SHN_UNDEF) &&
1298 (sym->st_shndx != SHN_COMMON)) {
1299 Is_desc *isp = sdp->sd_isc;
1300 Ifl_desc *ifl = sdp->sd_file;
1301
1302 if ((isp == NULL) || (isp->is_shdr == NULL) ||
1303 ((isp->is_shdr->sh_flags & SHF_TLS) == 0)) {
1304 ld_eprintf(ofl, ERR_FATAL,
1305 MSG_INTL(MSG_SYM_TLS),
1306 demangle(sdp->sd_name), ifl->ifl_name);
1307 continue;
1308 }
1309 }
1310
1311 if ((sdp->sd_flags & FLG_SY_VISIBLE) == 0)
1312 ld_sym_adjust_vis(sdp, ofl);
1313
1314 if ((sdp->sd_flags & FLG_SY_REDUCED) &&
1315 (oflags & FLG_OF_PROCRED)) {
1316 DBG_CALL(Dbg_syms_reduce(ofl, DBG_SYM_REDUCE_GLOBAL,
1317 sdp, 0, 0));
1318 }
1319
1320 /*
1321 * Record any STV_SINGLETON existence.
1322 */
1323 if ((vis = ELF_ST_VISIBILITY(sym->st_other)) == STV_SINGLETON)
1324 ofl->ofl_dtflags_1 |= DF_1_SINGLETON;
1325
1326 /*
1327 * If building a shared object or executable, and this is a
1328 * non-weak UNDEF symbol with reduced visibility (STV_*), then
1329 * give a fatal error.
1330 */
1331 if (((oflags & FLG_OF_RELOBJ) == 0) &&
1332 (sym->st_shndx == SHN_UNDEF) &&
1333 (ELF_ST_BIND(sym->st_info) != STB_WEAK)) {
1334 if (vis && (vis != STV_SINGLETON)) {
1335 sym_undef_entry(ofl, sdp, BNDLOCAL,
1336 FLG_OF_FATAL, &undef_state);
1337 continue;
1338 }
1339 }
1340
1341 /*
1342 * If this symbol is defined in a non-allocatable section,
1343 * reduce it to local symbol.
1344 */
1345 if (((isp = sdp->sd_isc) != 0) && isp->is_shdr &&
1346 ((isp->is_shdr->sh_flags & SHF_ALLOC) == 0)) {
1347 sdp->sd_flags |= (FLG_SY_REDUCED | FLG_SY_HIDDEN);
1348 }
1349
1350 /*
1351 * If this symbol originated as a SHN_SUNW_IGNORE, it will have
1352 * been processed as an SHN_UNDEF. Return the symbol to its
1353 * original index for validation, and propagation to the output
1354 * file.
1355 */
1356 if (sdp->sd_flags & FLG_SY_IGNORE)
1357 sdp->sd_shndx = SHN_SUNW_IGNORE;
1358
1359 if (undef) {
1360 /*
1361 * If a non-weak reference remains undefined, or if a
1362 * mapfile reference is not bound to the relocatable
1363 * objects that make up the object being built, we have
1364 * a fatal error.
1365 *
1366 * The exceptions are symbols which are defined to be
1367 * found in the parent (FLG_SY_PARENT), which is really
1368 * only meaningful for direct binding, or are defined
1369 * external (FLG_SY_EXTERN) so as to suppress -zdefs
1370 * errors.
1371 *
1372 * Register symbols are always allowed to be UNDEF.
1373 *
1374 * Note that we don't include references created via -u
1375 * in the same shared object binding test. This is for
1376 * backward compatibility, in that a number of archive
1377 * makefile rules used -u to cause archive extraction.
1378 * These same rules have been cut and pasted to apply
1379 * to shared objects, and thus although the -u reference
1380 * is redundant, flagging it as fatal could cause some
1381 * build to fail. Also we have documented the use of
1382 * -u as a mechanism to cause binding to weak version
1383 * definitions, thus giving users an error condition
1384 * would be incorrect.
1385 */
1386 if (!(sdp->sd_flags & FLG_SY_REGSYM) &&
1387 ((sym->st_shndx == SHN_UNDEF) &&
1388 ((ELF_ST_BIND(sym->st_info) != STB_WEAK) &&
1389 ((sdp->sd_flags &
1390 (FLG_SY_PARENT | FLG_SY_EXTERN)) == 0)) ||
1391 ((sdp->sd_flags &
1392 (FLG_SY_MAPREF | FLG_SY_MAPUSED | FLG_SY_HIDDEN |
1393 FLG_SY_PROTECT)) == FLG_SY_MAPREF))) {
1394 sym_undef_entry(ofl, sdp, UNDEF, undef,
1395 &undef_state);
1396 undeferr = 1;
1397 }
1398
1399 } else {
1400 /*
1401 * For building things like shared objects (or anything
1402 * -znodefs), undefined symbols are allowed.
1403 *
1404 * If a mapfile reference remains undefined the user
1405 * would probably like a warning at least (they've
1406 * usually mis-spelt the reference). Refer to the above
1407 * comments for discussion on -u references, which
1408 * are not tested for in the same manner.
1409 */
1410 if ((sdp->sd_flags &
1411 (FLG_SY_MAPREF | FLG_SY_MAPUSED)) ==
1412 FLG_SY_MAPREF) {
1413 sym_undef_entry(ofl, sdp, UNDEF, FLG_OF_WARN,
1414 &undef_state);
1415 undeferr = 1;
1416 }
1417 }
1418
1419 /*
1420 * If this symbol comes from a dependency mark the dependency
1421 * as required (-z ignore can result in unused dependencies
1422 * being dropped). If we need to record dependency versioning
1423 * information indicate what version of the needed shared object
1424 * this symbol is part of. Flag the symbol as undefined if it
1425 * has not been made available to us.
1426 */
1427 if ((sdp->sd_ref == REF_DYN_NEED) &&
1428 (!(sdp->sd_flags & FLG_SY_REFRSD))) {
1429 sdp->sd_file->ifl_flags |= FLG_IF_DEPREQD;
1430
1431 /*
1432 * Capture that we've bound to a symbol that doesn't
1433 * allow being directly bound to.
1434 */
1435 if (sdp->sd_flags & FLG_SY_NDIR)
1436 ofl->ofl_flags1 |= FLG_OF1_NGLBDIR;
1437
1438 if (sdp->sd_file->ifl_vercnt) {
1439 int vndx;
1440 Ver_index *vip;
1441
1442 vndx = sdp->sd_aux->sa_dverndx;
1443 vip = &sdp->sd_file->ifl_verndx[vndx];
1444 if (vip->vi_flags & FLG_VER_AVAIL) {
1445 vip->vi_flags |= FLG_VER_REFER;
1446 } else {
1447 sym_undef_entry(ofl, sdp, NOTAVAIL,
1448 FLG_OF_FATAL, &undef_state);
1449 continue;
1450 }
1451 }
1452 }
1453
1454 /*
1455 * Test that we do not bind to symbol supplied from an implicit
1456 * shared object. If a binding is from a weak reference it can
1457 * be ignored.
1458 */
1459 if (needed && !undeferr && (sdp->sd_flags & FLG_SY_GLOBREF) &&
1460 (sdp->sd_ref == REF_DYN_NEED) &&
1461 (sdp->sd_flags & FLG_SY_NOTAVAIL)) {
1462 sym_undef_entry(ofl, sdp, IMPLICIT, needed,
1463 &undef_state);
1464 if (needed == FLG_OF_FATAL)
1465 continue;
1466 }
1467
1468 /*
1469 * Test that a symbol isn't going to be reduced to local scope
1470 * which actually wants to bind to a shared object - if so it's
1471 * a fatal error.
1472 */
1473 if ((sdp->sd_ref == REF_DYN_NEED) &&
1474 (sdp->sd_flags & (FLG_SY_HIDDEN | FLG_SY_PROTECT))) {
1475 sym_undef_entry(ofl, sdp, BNDLOCAL, FLG_OF_FATAL,
1476 &undef_state);
1477 continue;
1478 }
1479
1480 /*
1481 * If the output image is to be versioned then all symbol
1482 * definitions must be associated with a version. Remove any
1483 * versioning that might be left associated with an undefined
1484 * symbol.
1485 */
1486 if (verdesc && (sdp->sd_ref == REF_REL_NEED)) {
1487 if (sym->st_shndx == SHN_UNDEF) {
1488 if (sdp->sd_aux && sdp->sd_aux->sa_overndx)
1489 sdp->sd_aux->sa_overndx = 0;
1490 } else {
1491 if (!SYM_IS_HIDDEN(sdp) && sdp->sd_aux &&
1492 (sdp->sd_aux->sa_overndx == 0)) {
1493 sym_undef_entry(ofl, sdp, NOVERSION,
1494 verdesc, &undef_state);
1495 continue;
1496 }
1497 }
1498 }
1499
1500 /*
1501 * If we don't need the symbol there's no need to process it
1502 * any further.
1503 */
1504 if (sdp->sd_ref == REF_DYN_SEEN)
1505 continue;
1506
1507 /*
1508 * Calculate the size and alignment requirements for the global
1509 * .bss and .tls sections. If we're building a relocatable
1510 * object only account for scoped COMMON symbols (these will
1511 * be converted to .bss references).
1512 *
1513 * When -z nopartial is in effect, partially initialized
1514 * symbols are directed to the special .data section
1515 * created for that purpose (ofl->ofl_isparexpn).
1516 * Otherwise, partially initialized symbols go to .bss.
1517 *
1518 * Also refer to make_mvsections() in sunwmove.c
1519 */
1520 if ((sym->st_shndx == SHN_COMMON) &&
1521 (((oflags & FLG_OF_RELOBJ) == 0) ||
1522 ld_sym_reducable(ofl, sdp))) {
1523 if ((sdp->sd_move == NULL) ||
1524 ((sdp->sd_flags & FLG_SY_PAREXPN) == 0)) {
1525 if (type != STT_TLS) {
1526 need_bss = TRUE;
1527 bsssize = (Xword)S_ROUND(bsssize,
1528 sym->st_value) + sym->st_size;
1529 if (sym->st_value > bssalign)
1530 bssalign = sym->st_value;
1531 } else {
1532 need_tlsbss = TRUE;
1533 tlssize = (Xword)S_ROUND(tlssize,
1534 sym->st_value) + sym->st_size;
1535 if (sym->st_value > tlsalign)
1536 tlsalign = sym->st_value;
1537 }
1538 }
1539 }
1540
1541 #if defined(_ELF64)
1542 /*
1543 * Calculate the size and alignment requirement for the global
1544 * .lbss. TLS or partially initialized symbols do not need to be
1545 * considered yet.
1546 */
1547 if ((ld_targ.t_m.m_mach == EM_AMD64) &&
1548 (sym->st_shndx == SHN_X86_64_LCOMMON)) {
1549 need_lbss = TRUE;
1550 lbsssize = (Xword)S_ROUND(lbsssize, sym->st_value) +
1551 sym->st_size;
1552 if (sym->st_value > lbssalign)
1553 lbssalign = sym->st_value;
1554 }
1555 #endif
1556 /*
1557 * If a symbol was referenced via the command line
1558 * (ld -u <>, ...), then this counts as a reference against the
1559 * symbol. Mark any section that symbol is defined in.
1560 */
1561 if (((isp = sdp->sd_isc) != 0) &&
1562 (sdp->sd_flags & FLG_SY_CMDREF)) {
1563 isp->is_flags |= FLG_IS_SECTREF;
1564 isp->is_file->ifl_flags |= FLG_IF_FILEREF;
1565 }
1566
1567 /*
1568 * Update the symbol count and the associated name string size.
1569 * Note, a capabilities symbol must remain as visible as a
1570 * global symbol. However, the runtime linker recognizes the
1571 * hidden requirement and ensures the symbol isn't made globally
1572 * available at runtime.
1573 */
1574 if (ld_sym_reducable(ofl, sdp)) {
1575 /*
1576 * If any reductions are being processed, keep a count
1577 * of eliminated symbols, and if the symbol is being
1578 * reduced to local, count it's size for the .symtab.
1579 */
1580 if (sdp->sd_flags & FLG_SY_ELIM) {
1581 ofl->ofl_elimcnt++;
1582 } else {
1583 ofl->ofl_scopecnt++;
1584 if ((((sdp->sd_flags & FLG_SY_REGSYM) == 0) ||
1585 sym->st_name) && (st_insert(ofl->ofl_strtab,
1586 sdp->sd_name) == -1))
1587 return (S_ERROR);
1588 if (allow_ldynsym && sym->st_name &&
1589 ldynsym_symtype[type]) {
1590 ofl->ofl_dynscopecnt++;
1591 if (st_insert(ofl->ofl_dynstrtab,
1592 sdp->sd_name) == -1)
1593 return (S_ERROR);
1594 /* Include it in sort section? */
1595 DYNSORT_COUNT(sdp, sym, type, ++);
1596 }
1597 }
1598 } else {
1599 ofl->ofl_globcnt++;
1600
1601 /*
1602 * Check to see if this global variable should go into
1603 * a sort section. Sort sections require a
1604 * .SUNW_ldynsym section, so, don't check unless a
1605 * .SUNW_ldynsym is allowed.
1606 */
1607 if (allow_ldynsym)
1608 DYNSORT_COUNT(sdp, sym, type, ++);
1609
1610 /*
1611 * If global direct bindings are in effect, or this
1612 * symbol has bound to a dependency which was specified
1613 * as requiring direct bindings, and it hasn't
1614 * explicitly been defined as a non-direct binding
1615 * symbol, mark it.
1616 */
1617 if (((ofl->ofl_dtflags_1 & DF_1_DIRECT) || (isp &&
1618 (isp->is_file->ifl_flags & FLG_IF_DIRECT))) &&
1619 ((sdp->sd_flags & FLG_SY_NDIR) == 0))
1620 sdp->sd_flags |= FLG_SY_DIR;
1621
1622 /*
1623 * Insert the symbol name.
1624 */
1625 if (((sdp->sd_flags & FLG_SY_REGSYM) == 0) ||
1626 sym->st_name) {
1627 if (st_insert(ofl->ofl_strtab,
1628 sdp->sd_name) == -1)
1629 return (S_ERROR);
1630
1631 if (!(ofl->ofl_flags & FLG_OF_RELOBJ) &&
1632 (st_insert(ofl->ofl_dynstrtab,
1633 sdp->sd_name) == -1))
1634 return (S_ERROR);
1635 }
1636
1637 /*
1638 * If this section offers a global symbol - record that
1639 * fact.
1640 */
1641 if (isp) {
1642 isp->is_flags |= FLG_IS_SECTREF;
1643 isp->is_file->ifl_flags |= FLG_IF_FILEREF;
1644 }
1645 }
1646 }
1647
1648 /*
1649 * Guidance: Use -z defs|nodefs when building shared objects.
1650 *
1651 * Our caller issues this, unless we mask it out here. So we mask it
1652 * out unless we've issued at least one warnings or fatal error.
1653 */
1654 if (!((oflags & FLG_OF_SHAROBJ) && OFL_GUIDANCE(ofl, FLG_OFG_NO_DEFS) &&
1655 (undef_state & (FLG_OF_FATAL | FLG_OF_WARN))))
1656 ofl->ofl_guideflags |= FLG_OFG_NO_DEFS;
1657
1658 /*
1659 * If we've encountered a fatal error during symbol validation then
1660 * return now.
1661 */
1662 if (ofl->ofl_flags & FLG_OF_FATAL)
1663 return (1);
1664
1665 /*
1666 * Now that symbol resolution is completed, scan any register symbols.
1667 * From now on, we're only interested in those that contribute to the
1668 * output file.
1669 */
1670 if (ofl->ofl_regsyms) {
1671 int ndx;
1672
1673 for (ndx = 0; ndx < ofl->ofl_regsymsno; ndx++) {
1674 if ((sdp = ofl->ofl_regsyms[ndx]) == NULL)
1675 continue;
1676 if (sdp->sd_ref != REF_REL_NEED) {
1677 ofl->ofl_regsyms[ndx] = NULL;
1678 continue;
1679 }
1680
1681 ofl->ofl_regsymcnt++;
1682 if (sdp->sd_sym->st_name == 0)
1683 sdp->sd_name = MSG_ORIG(MSG_STR_EMPTY);
1684
1685 if (SYM_IS_HIDDEN(sdp) ||
1686 (ELF_ST_BIND(sdp->sd_sym->st_info) == STB_LOCAL))
1687 ofl->ofl_lregsymcnt++;
1688 }
1689 }
1690
1691 /*
1692 * Generate the .bss section now that we know its size and alignment.
1693 */
1694 if (need_bss) {
1695 if (ld_make_bss(ofl, bsssize, bssalign,
1696 ld_targ.t_id.id_bss) == S_ERROR)
1697 return (S_ERROR);
1698 }
1699 if (need_tlsbss) {
1700 if (ld_make_bss(ofl, tlssize, tlsalign,
1701 ld_targ.t_id.id_tlsbss) == S_ERROR)
1702 return (S_ERROR);
1703 }
1704 #if defined(_ELF64)
1705 if ((ld_targ.t_m.m_mach == EM_AMD64) &&
1706 need_lbss && !(oflags & FLG_OF_RELOBJ)) {
1707 if (ld_make_bss(ofl, lbsssize, lbssalign,
1708 ld_targ.t_id.id_lbss) == S_ERROR)
1709 return (S_ERROR);
1710 }
1711 #endif
1712 /*
1713 * Determine what entry point symbol we need, and if found save its
1714 * symbol descriptor so that we can update the ELF header entry with the
1715 * symbols value later (see update_oehdr). Make sure the symbol is
1716 * tagged to ensure its update in case -s is in effect. Use any -e
1717 * option first, or the default entry points `_start' and `main'.
1718 */
1719 ret = 0;
1720 if (ofl->ofl_entry) {
1721 if ((sdp = ld_sym_find(ofl->ofl_entry, SYM_NOHASH,
1722 NULL, ofl)) == NULL) {
1723 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_ARG_NOENTRY),
1724 ofl->ofl_entry);
1725 ret++;
1726 } else if (ensure_sym_local(ofl, sdp,
1727 MSG_INTL(MSG_SYM_ENTRY)) != 0) {
1728 ret++;
1729 } else {
1730 ofl->ofl_entry = (void *)sdp;
1731 }
1732 } else if (((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_START),
1733 SYM_NOHASH, NULL, ofl)) != NULL) && (ensure_sym_local(ofl,
1734 sdp, 0) == 0)) {
1735 ofl->ofl_entry = (void *)sdp;
1736
1737 } else if (((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_MAIN),
1738 SYM_NOHASH, NULL, ofl)) != NULL) && (ensure_sym_local(ofl,
1739 sdp, 0) == 0)) {
1740 ofl->ofl_entry = (void *)sdp;
1741 }
1742
1743 /*
1744 * If ld -zdtrace=<sym> was given, then validate that the symbol is
1745 * defined within the current object being built.
1746 */
1747 if ((sdp = ofl->ofl_dtracesym) != 0)
1748 ret += ensure_sym_local(ofl, sdp, MSG_ORIG(MSG_STR_DTRACE));
1749
1750 /*
1751 * If any initarray, finiarray or preinitarray functions have been
1752 * requested, make sure they are defined within the current object
1753 * being built.
1754 */
1755 if (ofl->ofl_initarray) {
1756 ret += ensure_array_local(ofl, ofl->ofl_initarray,
1757 MSG_ORIG(MSG_SYM_INITARRAY));
1758 }
1759 if (ofl->ofl_finiarray) {
1760 ret += ensure_array_local(ofl, ofl->ofl_finiarray,
1761 MSG_ORIG(MSG_SYM_FINIARRAY));
1762 }
1763 if (ofl->ofl_preiarray) {
1764 ret += ensure_array_local(ofl, ofl->ofl_preiarray,
1765 MSG_ORIG(MSG_SYM_PREINITARRAY));
1766 }
1767
1768 if (ret)
1769 return (S_ERROR);
1770
1771 /*
1772 * If we're required to record any needed dependencies versioning
1773 * information calculate it now that all symbols have been validated.
1774 */
1775 if ((oflags & (FLG_OF_VERNEED | FLG_OF_NOVERSEC)) == FLG_OF_VERNEED)
1776 return (ld_vers_check_need(ofl));
1777 else
1778 return (1);
1779 }
1780
1781 /*
1782 * qsort(3c) comparison function. As an optimization for associating weak
1783 * symbols to their strong counterparts sort global symbols according to their
1784 * section index, address and binding.
1785 */
1786 static int
1787 compare(const void *sdpp1, const void *sdpp2)
1788 {
1789 Sym_desc *sdp1 = *((Sym_desc **)sdpp1);
1790 Sym_desc *sdp2 = *((Sym_desc **)sdpp2);
1791 Sym *sym1, *sym2;
1792 uchar_t bind1, bind2;
1793
1794 /*
1795 * Symbol descriptors may be zero, move these to the front of the
1796 * sorted array.
1797 */
1798 if (sdp1 == NULL)
1799 return (-1);
1800 if (sdp2 == NULL)
1801 return (1);
1802
1803 sym1 = sdp1->sd_sym;
1804 sym2 = sdp2->sd_sym;
1805
1806 /*
1807 * Compare the symbols section index. This is important when sorting
1808 * the symbol tables of relocatable objects. In this case, a symbols
1809 * value is the offset within the associated section, and thus many
1810 * symbols can have the same value, but are effectively different
1811 * addresses.
1812 */
1813 if (sym1->st_shndx > sym2->st_shndx)
1814 return (1);
1815 if (sym1->st_shndx < sym2->st_shndx)
1816 return (-1);
1817
1818 /*
1819 * Compare the symbols value (address).
1820 */
1821 if (sym1->st_value > sym2->st_value)
1822 return (1);
1823 if (sym1->st_value < sym2->st_value)
1824 return (-1);
1825
1826 bind1 = ELF_ST_BIND(sym1->st_info);
1827 bind2 = ELF_ST_BIND(sym2->st_info);
1828
1829 /*
1830 * If two symbols have the same address place the weak symbol before
1831 * any strong counterpart.
1832 */
1833 if (bind1 > bind2)
1834 return (-1);
1835 if (bind1 < bind2)
1836 return (1);
1837
1838 return (0);
1839 }
1840
1841 /*
1842 * Issue a MSG_SYM_BADADDR error from ld_sym_process(). This error
1843 * is issued when a symbol address/size is not contained by the
1844 * target section.
1845 *
1846 * Such objects are at least partially corrupt, and the user would
1847 * be well advised to be skeptical of them, and to ask their compiler
1848 * supplier to fix the problem. However, a distinction needs to be
1849 * made between symbols that reference readonly text, and those that
1850 * access writable data. Other than throwing off profiling results,
1851 * the readonly section case is less serious. We have encountered
1852 * such objects in the field. In order to allow existing objects
1853 * to continue working, we issue a warning rather than a fatal error
1854 * if the symbol is against readonly text. Other cases are fatal.
1855 */
1856 static void
1857 issue_badaddr_msg(Ifl_desc *ifl, Ofl_desc *ofl, Sym_desc *sdp,
1858 Sym *sym, Word shndx)
1859 {
1860 Error err;
1861 const char *msg;
1862
1863 if ((sdp->sd_isc->is_shdr->sh_flags & (SHF_WRITE | SHF_ALLOC)) ==
1864 SHF_ALLOC) {
1865 msg = MSG_INTL(MSG_SYM_BADADDR_ROTXT);
1866 err = ERR_WARNING;
1867 } else {
1868 msg = MSG_INTL(MSG_SYM_BADADDR);
1869 err = ERR_FATAL;
1870 }
1871
1872 ld_eprintf(ofl, err, msg, demangle(sdp->sd_name),
1873 ifl->ifl_name, shndx, sdp->sd_isc->is_name,
1874 EC_XWORD(sdp->sd_isc->is_shdr->sh_size),
1875 EC_XWORD(sym->st_value), EC_XWORD(sym->st_size));
1876 }
1877
1878 /*
1879 * Global symbols that are candidates for translation to local capability
1880 * symbols under -z symbolcap, are maintained on a local symbol list. Once
1881 * all symbols of a file are processed, this list is traversed to cull any
1882 * unnecessary weak symbol aliases.
1883 */
1884 typedef struct {
1885 Sym_desc *c_nsdp; /* new lead symbol */
1886 Sym_desc *c_osdp; /* original symbol */
1887 Cap_group *c_group; /* symbol capability group */
1888 Word c_ndx; /* symbol index */
1889 } Cap_pair;
1890
1891 /*
1892 * Process the symbol table for the specified input file. At this point all
1893 * input sections from this input file have been assigned an input section
1894 * descriptor which is saved in the `ifl_isdesc' array.
1895 *
1896 * - local symbols are saved (as is) if the input file is a relocatable
1897 * object
1898 *
1899 * - global symbols are added to the linkers internal symbol table if they
1900 * are not already present, otherwise a symbol resolution function is
1901 * called upon to resolve the conflict.
1902 */
1903 uintptr_t
1904 ld_sym_process(Is_desc *isc, Ifl_desc *ifl, Ofl_desc *ofl)
1905 {
1906 /*
1907 * This macro tests the given symbol to see if it is out of
1908 * range relative to the section it references.
1909 *
1910 * entry:
1911 * - ifl is a relative object (ET_REL)
1912 * _sdp - Symbol descriptor
1913 * _sym - Symbol
1914 * _type - Symbol type
1915 *
1916 * The following are tested:
1917 * - Symbol length is non-zero
1918 * - Symbol type is a type that references code or data
1919 * - Referenced section is not 0 (indicates an UNDEF symbol)
1920 * and is not in the range of special values above SHN_LORESERVE
1921 * (excluding SHN_XINDEX, which is OK).
1922 * - We have a valid section header for the target section
1923 *
1924 * If the above are all true, and the symbol position is not
1925 * contained by the target section, this macro evaluates to
1926 * True (1). Otherwise, False(0).
1927 */
1928 #define SYM_LOC_BADADDR(_sdp, _sym, _type) \
1929 (_sym->st_size && dynsymsort_symtype[_type] && \
1930 (_sym->st_shndx != SHN_UNDEF) && \
1931 ((_sym->st_shndx < SHN_LORESERVE) || \
1932 (_sym->st_shndx == SHN_XINDEX)) && \
1933 _sdp->sd_isc && _sdp->sd_isc->is_shdr && \
1934 ((_sym->st_value + _sym->st_size) > _sdp->sd_isc->is_shdr->sh_size))
1935
1936 Conv_inv_buf_t inv_buf;
1937 Sym *sym = (Sym *)isc->is_indata->d_buf;
1938 Word *symshndx = NULL;
1939 Shdr *shdr = isc->is_shdr;
1940 Sym_desc *sdp;
1941 size_t strsize;
1942 char *strs;
1943 uchar_t type, bind;
1944 Word ndx, hash, local, total;
1945 uchar_t osabi = ifl->ifl_ehdr->e_ident[EI_OSABI];
1946 Half mach = ifl->ifl_ehdr->e_machine;
1947 Half etype = ifl->ifl_ehdr->e_type;
1948 int etype_rel;
1949 const char *symsecname, *strsecname;
1950 Word symsecndx;
1951 avl_index_t where;
1952 int test_gnu_hidden_bit, weak;
1953 Cap_desc *cdp = NULL;
1954 Alist *cappairs = NULL;
1955
1956 /*
1957 * Its possible that a file may contain more that one symbol table,
1958 * ie. .dynsym and .symtab in a shared library. Only process the first
1959 * table (here, we assume .dynsym comes before .symtab).
1960 */
1961 if (ifl->ifl_symscnt)
1962 return (1);
1963
1964 if (isc->is_symshndx)
1965 symshndx = isc->is_symshndx->is_indata->d_buf;
1966
1967 DBG_CALL(Dbg_syms_process(ofl->ofl_lml, ifl));
1968
1969 symsecndx = isc->is_scnndx;
1970 if (isc->is_name)
1971 symsecname = isc->is_name;
1972 else
1973 symsecname = MSG_ORIG(MSG_STR_EMPTY);
1974
1975 /*
1976 * From the symbol tables section header information determine which
1977 * strtab table is needed to locate the actual symbol names.
1978 */
1979 if (ifl->ifl_flags & FLG_IF_HSTRTAB) {
1980 ndx = shdr->sh_link;
1981 if ((ndx == 0) || (ndx >= ifl->ifl_shnum)) {
1982 ld_eprintf(ofl, ERR_FATAL,
1983 MSG_INTL(MSG_FIL_INVSHLINK), ifl->ifl_name,
1984 EC_WORD(symsecndx), symsecname, EC_XWORD(ndx));
1985 return (S_ERROR);
1986 }
1987 strsize = ifl->ifl_isdesc[ndx]->is_shdr->sh_size;
1988 strs = ifl->ifl_isdesc[ndx]->is_indata->d_buf;
1989 if (ifl->ifl_isdesc[ndx]->is_name)
1990 strsecname = ifl->ifl_isdesc[ndx]->is_name;
1991 else
1992 strsecname = MSG_ORIG(MSG_STR_EMPTY);
1993 } else {
1994 /*
1995 * There is no string table section in this input file
1996 * although there are symbols in this symbol table section.
1997 * This means that these symbols do not have names.
1998 * Currently, only scratch register symbols are allowed
1999 * not to have names.
2000 */
2001 strsize = 0;
2002 strs = (char *)MSG_ORIG(MSG_STR_EMPTY);
2003 strsecname = MSG_ORIG(MSG_STR_EMPTY);
2004 }
2005
2006 /*
2007 * Determine the number of local symbols together with the total
2008 * number we have to process.
2009 */
2010 total = (Word)(shdr->sh_size / shdr->sh_entsize);
2011 local = shdr->sh_info;
2012
2013 /*
2014 * Allocate a symbol table index array and a local symbol array
2015 * (global symbols are processed and added to the ofl->ofl_symbkt[]
2016 * array). If we are dealing with a relocatable object, allocate the
2017 * local symbol descriptors. If this isn't a relocatable object we
2018 * still have to process any shared object locals to determine if any
2019 * register symbols exist. Although these aren't added to the output
2020 * image, they are used as part of symbol resolution.
2021 */
2022 if ((ifl->ifl_oldndx = libld_malloc((size_t)(total *
2023 sizeof (Sym_desc *)))) == NULL)
2024 return (S_ERROR);
2025 etype_rel = (etype == ET_REL);
2026 if (etype_rel && local) {
2027 if ((ifl->ifl_locs =
2028 libld_calloc(sizeof (Sym_desc), local)) == NULL)
2029 return (S_ERROR);
2030 /* LINTED */
2031 ifl->ifl_locscnt = (Word)local;
2032 }
2033 ifl->ifl_symscnt = total;
2034
2035 /*
2036 * If there are local symbols to save add them to the symbol table
2037 * index array.
2038 */
2039 if (local) {
2040 int allow_ldynsym = OFL_ALLOW_LDYNSYM(ofl);
2041 Sym_desc *last_file_sdp = NULL;
2042 int last_file_ndx = 0;
2043
2044 for (sym++, ndx = 1; ndx < local; sym++, ndx++) {
2045 sd_flag_t sdflags = FLG_SY_CLEAN;
2046 Word shndx;
2047 const char *name;
2048 Sym_desc *rsdp;
2049 int shndx_bad = 0;
2050 int symtab_enter = 1;
2051
2052 /*
2053 * Determine and validate the associated section index.
2054 */
2055 if (symshndx && (sym->st_shndx == SHN_XINDEX)) {
2056 shndx = symshndx[ndx];
2057 } else if ((shndx = sym->st_shndx) >= SHN_LORESERVE) {
2058 sdflags |= FLG_SY_SPECSEC;
2059 } else if (shndx > ifl->ifl_shnum) {
2060 /* We need the name before we can issue error */
2061 shndx_bad = 1;
2062 }
2063
2064 /*
2065 * Check if st_name has a valid value or not.
2066 */
2067 if ((name = string(ofl, ifl, sym, strs, strsize, ndx,
2068 shndx, symsecndx, symsecname, strsecname,
2069 &sdflags)) == NULL)
2070 continue;
2071
2072 /*
2073 * Now that we have the name, if the section index
2074 * was bad, report it.
2075 */
2076 if (shndx_bad) {
2077 ld_eprintf(ofl, ERR_WARNING,
2078 MSG_INTL(MSG_SYM_INVSHNDX),
2079 demangle_symname(name, symsecname, ndx),
2080 ifl->ifl_name,
2081 conv_sym_shndx(osabi, mach, sym->st_shndx,
2082 CONV_FMT_DECIMAL, &inv_buf));
2083 continue;
2084 }
2085
2086 /*
2087 * If this local symbol table originates from a shared
2088 * object, then we're only interested in recording
2089 * register symbols. As local symbol descriptors aren't
2090 * allocated for shared objects, one will be allocated
2091 * to associated with the register symbol. This symbol
2092 * won't become part of the output image, but we must
2093 * process it to test for register conflicts.
2094 */
2095 rsdp = sdp = NULL;
2096 if (sdflags & FLG_SY_REGSYM) {
2097 /*
2098 * The presence of FLG_SY_REGSYM means that
2099 * the pointers in ld_targ.t_ms are non-NULL.
2100 */
2101 rsdp = (*ld_targ.t_ms.ms_reg_find)(sym, ofl);
2102 if (rsdp != 0) {
2103 /*
2104 * The fact that another register def-
2105 * inition has been found is fatal.
2106 * Call the verification routine to get
2107 * the error message and move on.
2108 */
2109 (void) (*ld_targ.t_ms.ms_reg_check)
2110 (rsdp, sym, name, ifl, ofl);
2111 continue;
2112 }
2113
2114 if (etype == ET_DYN) {
2115 if ((sdp = libld_calloc(
2116 sizeof (Sym_desc), 1)) == NULL)
2117 return (S_ERROR);
2118 sdp->sd_ref = REF_DYN_SEEN;
2119
2120 /* Will not appear in output object */
2121 symtab_enter = 0;
2122 }
2123 } else if (etype == ET_DYN)
2124 continue;
2125
2126 /*
2127 * Fill in the remaining symbol descriptor information.
2128 */
2129 if (sdp == NULL) {
2130 sdp = &(ifl->ifl_locs[ndx]);
2131 sdp->sd_ref = REF_REL_NEED;
2132 sdp->sd_symndx = ndx;
2133 }
2134 if (rsdp == NULL) {
2135 sdp->sd_name = name;
2136 sdp->sd_sym = sym;
2137 sdp->sd_shndx = shndx;
2138 sdp->sd_flags = sdflags;
2139 sdp->sd_file = ifl;
2140 ifl->ifl_oldndx[ndx] = sdp;
2141 }
2142
2143 DBG_CALL(Dbg_syms_entry(ofl->ofl_lml, ndx, sdp));
2144
2145 /*
2146 * Reclassify any SHN_SUNW_IGNORE symbols to SHN_UNDEF
2147 * so as to simplify future processing.
2148 */
2149 if (sym->st_shndx == SHN_SUNW_IGNORE) {
2150 sdp->sd_shndx = shndx = SHN_UNDEF;
2151 sdp->sd_flags |= (FLG_SY_IGNORE | FLG_SY_ELIM);
2152 }
2153
2154 /*
2155 * Process any register symbols.
2156 */
2157 if (sdp->sd_flags & FLG_SY_REGSYM) {
2158 /*
2159 * Add a diagnostic to indicate we've caught a
2160 * register symbol, as this can be useful if a
2161 * register conflict is later discovered.
2162 */
2163 DBG_CALL(Dbg_syms_entered(ofl, sym, sdp));
2164
2165 /*
2166 * If this register symbol hasn't already been
2167 * recorded, enter it now.
2168 *
2169 * The presence of FLG_SY_REGSYM means that
2170 * the pointers in ld_targ.t_ms are non-NULL.
2171 */
2172 if ((rsdp == NULL) &&
2173 ((*ld_targ.t_ms.ms_reg_enter)(sdp, ofl) ==
2174 0))
2175 return (S_ERROR);
2176 }
2177
2178 /*
2179 * Assign an input section.
2180 */
2181 if ((sym->st_shndx != SHN_UNDEF) &&
2182 ((sdp->sd_flags & FLG_SY_SPECSEC) == 0))
2183 sdp->sd_isc = ifl->ifl_isdesc[shndx];
2184
2185 /*
2186 * If this symbol falls within the range of a section
2187 * being discarded, then discard the symbol itself.
2188 * There is no reason to keep this local symbol.
2189 */
2190 if (sdp->sd_isc &&
2191 (sdp->sd_isc->is_flags & FLG_IS_DISCARD)) {
2192 sdp->sd_flags |= FLG_SY_ISDISC;
2193 DBG_CALL(Dbg_syms_discarded(ofl->ofl_lml, sdp));
2194 continue;
2195 }
2196
2197 /*
2198 * Skip any section symbols as new versions of these
2199 * will be created.
2200 */
2201 if ((type = ELF_ST_TYPE(sym->st_info)) == STT_SECTION) {
2202 if (sym->st_shndx == SHN_UNDEF) {
2203 ld_eprintf(ofl, ERR_WARNING,
2204 MSG_INTL(MSG_SYM_INVSHNDX),
2205 demangle_symname(name, symsecname,
2206 ndx), ifl->ifl_name,
2207 conv_sym_shndx(osabi, mach,
2208 sym->st_shndx, CONV_FMT_DECIMAL,
2209 &inv_buf));
2210 }
2211 continue;
2212 }
2213
2214 /*
2215 * For a relocatable object, if this symbol is defined
2216 * and has non-zero length and references an address
2217 * within an associated section, then check its extents
2218 * to make sure the section boundaries encompass it.
2219 * If they don't, the ELF file is corrupt.
2220 */
2221 if (etype_rel) {
2222 if (SYM_LOC_BADADDR(sdp, sym, type)) {
2223 issue_badaddr_msg(ifl, ofl, sdp,
2224 sym, shndx);
2225 if (ofl->ofl_flags & FLG_OF_FATAL)
2226 continue;
2227 }
2228
2229 /*
2230 * We have observed relocatable objects
2231 * containing identical adjacent STT_FILE
2232 * symbols. Discard any other than the first,
2233 * as they are all equivalent and the extras
2234 * do not add information.
2235 *
2236 * For the purpose of this test, we assume
2237 * that only the symbol type and the string
2238 * table offset (st_name) matter.
2239 */
2240 if (type == STT_FILE) {
2241 int toss = (last_file_sdp != NULL) &&
2242 ((ndx - 1) == last_file_ndx) &&
2243 (sym->st_name ==
2244 last_file_sdp->sd_sym->st_name);
2245
2246 last_file_sdp = sdp;
2247 last_file_ndx = ndx;
2248 if (toss) {
2249 sdp->sd_flags |= FLG_SY_INVALID;
2250 DBG_CALL(Dbg_syms_dup_discarded(
2251 ofl->ofl_lml, ndx, sdp));
2252 continue;
2253 }
2254 }
2255 }
2256
2257
2258 /*
2259 * Sanity check for TLS
2260 */
2261 if ((sym->st_size != 0) && ((type == STT_TLS) &&
2262 (sym->st_shndx != SHN_COMMON))) {
2263 Is_desc *isp = sdp->sd_isc;
2264
2265 if ((isp == NULL) || (isp->is_shdr == NULL) ||
2266 ((isp->is_shdr->sh_flags & SHF_TLS) == 0)) {
2267 ld_eprintf(ofl, ERR_FATAL,
2268 MSG_INTL(MSG_SYM_TLS),
2269 demangle(sdp->sd_name),
2270 ifl->ifl_name);
2271 continue;
2272 }
2273 }
2274
2275 /*
2276 * Carry our some basic sanity checks (these are just
2277 * some of the erroneous symbol entries we've come
2278 * across, there's probably a lot more). The symbol
2279 * will not be carried forward to the output file, which
2280 * won't be a problem unless a relocation is required
2281 * against it.
2282 */
2283 if (((sdp->sd_flags & FLG_SY_SPECSEC) &&
2284 ((sym->st_shndx == SHN_COMMON)) ||
2285 ((type == STT_FILE) &&
2286 (sym->st_shndx != SHN_ABS))) ||
2287 (sdp->sd_isc && (sdp->sd_isc->is_osdesc == NULL))) {
2288 ld_eprintf(ofl, ERR_WARNING,
2289 MSG_INTL(MSG_SYM_INVSHNDX),
2290 demangle_symname(name, symsecname, ndx),
2291 ifl->ifl_name,
2292 conv_sym_shndx(osabi, mach, sym->st_shndx,
2293 CONV_FMT_DECIMAL, &inv_buf));
2294 sdp->sd_isc = NULL;
2295 sdp->sd_flags |= FLG_SY_INVALID;
2296 continue;
2297 }
2298
2299 /*
2300 * As these local symbols will become part of the output
2301 * image, record their number and name string size.
2302 * Globals are counted after all input file processing
2303 * (and hence symbol resolution) is complete during
2304 * sym_validate().
2305 */
2306 if (!(ofl->ofl_flags & FLG_OF_REDLSYM) &&
2307 symtab_enter) {
2308 ofl->ofl_locscnt++;
2309
2310 if ((((sdp->sd_flags & FLG_SY_REGSYM) == 0) ||
2311 sym->st_name) && (st_insert(ofl->ofl_strtab,
2312 sdp->sd_name) == -1))
2313 return (S_ERROR);
2314
2315 if (allow_ldynsym && sym->st_name &&
2316 ldynsym_symtype[type]) {
2317 ofl->ofl_dynlocscnt++;
2318 if (st_insert(ofl->ofl_dynstrtab,
2319 sdp->sd_name) == -1)
2320 return (S_ERROR);
2321 /* Include it in sort section? */
2322 DYNSORT_COUNT(sdp, sym, type, ++);
2323 }
2324 }
2325 }
2326 }
2327
2328 /*
2329 * The GNU ld interprets the top bit of the 16-bit Versym value
2330 * (0x8000) as the "hidden" bit. If this bit is set, the linker
2331 * is supposed to act as if that symbol does not exist. The Solaris
2332 * linker does not support this mechanism, or the model of interface
2333 * evolution that it allows, but we honor it in GNU ld produced
2334 * objects in order to interoperate with them.
2335 *
2336 * Determine if we should honor the GNU hidden bit for this file.
2337 */
2338 test_gnu_hidden_bit = ((ifl->ifl_flags & FLG_IF_GNUVER) != 0) &&
2339 (ifl->ifl_versym != NULL);
2340
2341 /*
2342 * Determine whether object capabilities for this file are being
2343 * converted into symbol capabilities. If so, global function symbols,
2344 * and initialized global data symbols, need special translation and
2345 * processing.
2346 */
2347 if ((etype == ET_REL) && (ifl->ifl_flags & FLG_IF_OTOSCAP))
2348 cdp = ifl->ifl_caps;
2349
2350 /*
2351 * Now scan the global symbols entering them in the internal symbol
2352 * table or resolving them as necessary.
2353 */
2354 sym = (Sym *)isc->is_indata->d_buf;
2355 sym += local;
2356 weak = 0;
2357 /* LINTED */
2358 for (ndx = (int)local; ndx < total; sym++, ndx++) {
2359 const char *name;
2360 sd_flag_t sdflags = 0;
2361 Word shndx;
2362 int shndx_bad = 0;
2363 Sym *nsym = sym;
2364 Cap_pair *cpp = NULL;
2365 uchar_t ntype;
2366
2367 /*
2368 * Determine and validate the associated section index.
2369 */
2370 if (symshndx && (nsym->st_shndx == SHN_XINDEX)) {
2371 shndx = symshndx[ndx];
2372 } else if ((shndx = nsym->st_shndx) >= SHN_LORESERVE) {
2373 sdflags |= FLG_SY_SPECSEC;
2374 } else if (shndx > ifl->ifl_shnum) {
2375 /* We need the name before we can issue error */
2376 shndx_bad = 1;
2377 }
2378
2379 /*
2380 * Check if st_name has a valid value or not.
2381 */
2382 if ((name = string(ofl, ifl, nsym, strs, strsize, ndx, shndx,
2383 symsecndx, symsecname, strsecname, &sdflags)) == NULL)
2384 continue;
2385
2386 /*
2387 * Now that we have the name, report an erroneous section index.
2388 */
2389 if (shndx_bad) {
2390 ld_eprintf(ofl, ERR_WARNING, MSG_INTL(MSG_SYM_INVSHNDX),
2391 demangle_symname(name, symsecname, ndx),
2392 ifl->ifl_name,
2393 conv_sym_shndx(osabi, mach, nsym->st_shndx,
2394 CONV_FMT_DECIMAL, &inv_buf));
2395 continue;
2396 }
2397
2398 /*
2399 * Test for the GNU hidden bit, and ignore symbols that
2400 * have it set.
2401 */
2402 if (test_gnu_hidden_bit &&
2403 ((ifl->ifl_versym[ndx] & 0x8000) != 0))
2404 continue;
2405
2406 /*
2407 * The linker itself will generate symbols for _end, _etext,
2408 * _edata, _DYNAMIC and _PROCEDURE_LINKAGE_TABLE_, so don't
2409 * bother entering these symbols from shared objects. This
2410 * results in some wasted resolution processing, which is hard
2411 * to feel, but if nothing else, pollutes diagnostic relocation
2412 * output.
2413 */
2414 if (name[0] && (etype == ET_DYN) && (nsym->st_size == 0) &&
2415 (ELF_ST_TYPE(nsym->st_info) == STT_OBJECT) &&
2416 (name[0] == '_') && ((name[1] == 'e') ||
2417 (name[1] == 'D') || (name[1] == 'P')) &&
2418 ((strcmp(name, MSG_ORIG(MSG_SYM_ETEXT_U)) == 0) ||
2419 (strcmp(name, MSG_ORIG(MSG_SYM_EDATA_U)) == 0) ||
2420 (strcmp(name, MSG_ORIG(MSG_SYM_END_U)) == 0) ||
2421 (strcmp(name, MSG_ORIG(MSG_SYM_DYNAMIC_U)) == 0) ||
2422 (strcmp(name, MSG_ORIG(MSG_SYM_PLKTBL_U)) == 0))) {
2423 ifl->ifl_oldndx[ndx] = 0;
2424 continue;
2425 }
2426
2427 /*
2428 * The '-z wrap=XXX' option emulates the GNU ld --wrap=XXX
2429 * option. When XXX is the symbol to be wrapped:
2430 *
2431 * - An undefined reference to XXX is converted to __wrap_XXX
2432 * - An undefined reference to __real_XXX is converted to XXX
2433 *
2434 * The idea is that the user can supply a wrapper function
2435 * __wrap_XXX that does some work, and then uses the name
2436 * __real_XXX to pass the call on to the real function. The
2437 * wrapper objects are linked with the original unmodified
2438 * objects to produce a wrapped version of the output object.
2439 */
2440 if (ofl->ofl_wrap && name[0] && (shndx == SHN_UNDEF)) {
2441 WrapSymNode wsn, *wsnp;
2442
2443 /*
2444 * If this is the __real_XXX form, advance the
2445 * pointer to reference the wrapped name.
2446 */
2447 wsn.wsn_name = name;
2448 if ((*name == '_') &&
2449 (strncmp(name, MSG_ORIG(MSG_STR_UU_REAL_U),
2450 MSG_STR_UU_REAL_U_SIZE) == 0))
2451 wsn.wsn_name += MSG_STR_UU_REAL_U_SIZE;
2452
2453 /*
2454 * Is this symbol in the wrap AVL tree? If so, map
2455 * XXX to __wrap_XXX, and __real_XXX to XXX. Note that
2456 * wsn.wsn_name will equal the current value of name
2457 * if the __real_ prefix is not present.
2458 */
2459 if ((wsnp = avl_find(ofl->ofl_wrap, &wsn, 0)) != NULL) {
2460 const char *old_name = name;
2461
2462 name = (wsn.wsn_name == name) ?
2463 wsnp->wsn_wrapname : wsn.wsn_name;
2464 DBG_CALL(Dbg_syms_wrap(ofl->ofl_lml, ndx,
2465 old_name, name));
2466 }
2467 }
2468
2469 /*
2470 * Determine and validate the symbols binding.
2471 */
2472 bind = ELF_ST_BIND(nsym->st_info);
2473 if ((bind != STB_GLOBAL) && (bind != STB_WEAK)) {
2474 ld_eprintf(ofl, ERR_WARNING, MSG_INTL(MSG_SYM_NONGLOB),
2475 demangle_symname(name, symsecname, ndx),
2476 ifl->ifl_name,
2477 conv_sym_info_bind(bind, 0, &inv_buf));
2478 continue;
2479 }
2480 if (bind == STB_WEAK)
2481 weak++;
2482
2483 /*
2484 * If this symbol falls within the range of a section being
2485 * discarded, then discard the symbol itself.
2486 */
2487 if (((sdflags & FLG_SY_SPECSEC) == 0) &&
2488 (nsym->st_shndx != SHN_UNDEF)) {
2489 Is_desc *isp;
2490
2491 if (shndx >= ifl->ifl_shnum) {
2492 /*
2493 * Carry our some basic sanity checks
2494 * The symbol will not be carried forward to
2495 * the output file, which won't be a problem
2496 * unless a relocation is required against it.
2497 */
2498 ld_eprintf(ofl, ERR_WARNING,
2499 MSG_INTL(MSG_SYM_INVSHNDX),
2500 demangle_symname(name, symsecname, ndx),
2501 ifl->ifl_name,
2502 conv_sym_shndx(osabi, mach, nsym->st_shndx,
2503 CONV_FMT_DECIMAL, &inv_buf));
2504 continue;
2505 }
2506
2507 isp = ifl->ifl_isdesc[shndx];
2508 if (isp && (isp->is_flags & FLG_IS_DISCARD)) {
2509 if ((sdp =
2510 libld_calloc(sizeof (Sym_desc), 1)) == NULL)
2511 return (S_ERROR);
2512
2513 /*
2514 * Create a dummy symbol entry so that if we
2515 * find any references to this discarded symbol
2516 * we can compensate.
2517 */
2518 sdp->sd_name = name;
2519 sdp->sd_sym = nsym;
2520 sdp->sd_file = ifl;
2521 sdp->sd_isc = isp;
2522 sdp->sd_flags = FLG_SY_ISDISC;
2523 ifl->ifl_oldndx[ndx] = sdp;
2524
2525 DBG_CALL(Dbg_syms_discarded(ofl->ofl_lml, sdp));
2526 continue;
2527 }
2528 }
2529
2530 /*
2531 * If object capabilities for this file are being converted
2532 * into symbol capabilities, then:
2533 *
2534 * - Any global function, or initialized global data symbol
2535 * definitions (ie., those that are not associated with
2536 * special symbol types, ie., ABS, COMMON, etc.), and which
2537 * have not been reduced to locals, are converted to symbol
2538 * references (UNDEF). This ensures that any reference to
2539 * the original symbol, for example from a relocation, get
2540 * associated to a capabilities family lead symbol, ie., a
2541 * generic instance.
2542 *
2543 * - For each global function, or object symbol definition,
2544 * a new local symbol is created. The function or object
2545 * is renamed using the capabilities CA_SUNW_ID definition
2546 * (which might have been fabricated for this purpose -
2547 * see get_cap_group()). The new symbol name is:
2548 *
2549 * <original name>%<capability group identifier>
2550 *
2551 * This symbol is associated to the same location, and
2552 * becomes a capabilities family member.
2553 */
2554 /* LINTED */
2555 hash = (Word)elf_hash(name);
2556
2557 ntype = ELF_ST_TYPE(nsym->st_info);
2558 if (cdp && (nsym->st_shndx != SHN_UNDEF) &&
2559 ((sdflags & FLG_SY_SPECSEC) == 0) &&
2560 ((ntype == STT_FUNC) || (ntype == STT_OBJECT))) {
2561 /*
2562 * Determine this symbol's visibility. If a mapfile has
2563 * indicated this symbol should be local, then there's
2564 * no point in transforming this global symbol to a
2565 * capabilities symbol. Otherwise, create a symbol
2566 * capability pair descriptor to record this symbol as
2567 * a candidate for translation.
2568 */
2569 if (sym_cap_vis(name, hash, sym, ofl) &&
2570 ((cpp = alist_append(&cappairs, NULL,
2571 sizeof (Cap_pair), AL_CNT_CAP_PAIRS)) == NULL))
2572 return (S_ERROR);
2573 }
2574
2575 if (cpp) {
2576 Sym *rsym;
2577
2578 DBG_CALL(Dbg_syms_cap_convert(ofl, ndx, name, nsym));
2579
2580 /*
2581 * Allocate a new symbol descriptor to represent the
2582 * transformed global symbol. The descriptor points
2583 * to the original symbol information (which might
2584 * indicate a global or weak visibility). The symbol
2585 * information will be transformed into a local symbol
2586 * later, after any weak aliases are culled.
2587 */
2588 if ((cpp->c_osdp =
2589 libld_malloc(sizeof (Sym_desc))) == NULL)
2590 return (S_ERROR);
2591
2592 cpp->c_osdp->sd_name = name;
2593 cpp->c_osdp->sd_sym = nsym;
2594 cpp->c_osdp->sd_shndx = shndx;
2595 cpp->c_osdp->sd_file = ifl;
2596 cpp->c_osdp->sd_isc = ifl->ifl_isdesc[shndx];
2597 cpp->c_osdp->sd_ref = REF_REL_NEED;
2598
2599 /*
2600 * Save the capabilities group this symbol belongs to,
2601 * and the original symbol index.
2602 */
2603 cpp->c_group = cdp->ca_groups->apl_data[0];
2604 cpp->c_ndx = ndx;
2605
2606 /*
2607 * Replace the original symbol definition with a symbol
2608 * reference. Make sure this reference isn't left as a
2609 * weak.
2610 */
2611 if ((rsym = libld_malloc(sizeof (Sym))) == NULL)
2612 return (S_ERROR);
2613
2614 *rsym = *nsym;
2615
2616 rsym->st_info = ELF_ST_INFO(STB_GLOBAL, ntype);
2617 rsym->st_shndx = shndx = SHN_UNDEF;
2618 rsym->st_value = 0;
2619 rsym->st_size = 0;
2620
2621 sdflags |= FLG_SY_CAP;
2622
2623 nsym = rsym;
2624 }
2625
2626 /*
2627 * If the symbol does not already exist in the internal symbol
2628 * table add it, otherwise resolve the conflict. If the symbol
2629 * from this file is kept, retain its symbol table index for
2630 * possible use in associating a global alias.
2631 */
2632 if ((sdp = ld_sym_find(name, hash, &where, ofl)) == NULL) {
2633 DBG_CALL(Dbg_syms_global(ofl->ofl_lml, ndx, name));
2634 if ((sdp = ld_sym_enter(name, nsym, hash, ifl, ofl, ndx,
2635 shndx, sdflags, &where)) == (Sym_desc *)S_ERROR)
2636 return (S_ERROR);
2637
2638 } else if (ld_sym_resolve(sdp, nsym, ifl, ofl, ndx, shndx,
2639 sdflags) == S_ERROR)
2640 return (S_ERROR);
2641
2642 /*
2643 * Now that we have a symbol descriptor, retain the descriptor
2644 * for later use by symbol capabilities processing.
2645 */
2646 if (cpp)
2647 cpp->c_nsdp = sdp;
2648
2649 /*
2650 * After we've compared a defined symbol in one shared
2651 * object, flag the symbol so we don't compare it again.
2652 */
2653 if ((etype == ET_DYN) && (nsym->st_shndx != SHN_UNDEF) &&
2654 ((sdp->sd_flags & FLG_SY_SOFOUND) == 0))
2655 sdp->sd_flags |= FLG_SY_SOFOUND;
2656
2657 /*
2658 * If the symbol is accepted from this file retain the symbol
2659 * index for possible use in aliasing.
2660 */
2661 if (sdp->sd_file == ifl)
2662 sdp->sd_symndx = ndx;
2663
2664 ifl->ifl_oldndx[ndx] = sdp;
2665
2666 /*
2667 * If we've accepted a register symbol, continue to validate
2668 * it.
2669 */
2670 if (sdp->sd_flags & FLG_SY_REGSYM) {
2671 Sym_desc *rsdp;
2672
2673 /*
2674 * The presence of FLG_SY_REGSYM means that
2675 * the pointers in ld_targ.t_ms are non-NULL.
2676 */
2677 rsdp = (*ld_targ.t_ms.ms_reg_find)(sdp->sd_sym, ofl);
2678 if (rsdp == NULL) {
2679 if ((*ld_targ.t_ms.ms_reg_enter)(sdp, ofl) == 0)
2680 return (S_ERROR);
2681 } else if (rsdp != sdp) {
2682 (void) (*ld_targ.t_ms.ms_reg_check)(rsdp,
2683 sdp->sd_sym, sdp->sd_name, ifl, ofl);
2684 }
2685 }
2686
2687 /*
2688 * For a relocatable object, if this symbol is defined
2689 * and has non-zero length and references an address
2690 * within an associated section, then check its extents
2691 * to make sure the section boundaries encompass it.
2692 * If they don't, the ELF file is corrupt. Note that this
2693 * global symbol may have come from another file to satisfy
2694 * an UNDEF symbol of the same name from this one. In that
2695 * case, we don't check it, because it was already checked
2696 * as part of its own file.
2697 */
2698 if (etype_rel && (sdp->sd_file == ifl)) {
2699 Sym *tsym = sdp->sd_sym;
2700
2701 if (SYM_LOC_BADADDR(sdp, tsym,
2702 ELF_ST_TYPE(tsym->st_info))) {
2703 issue_badaddr_msg(ifl, ofl, sdp,
2704 tsym, tsym->st_shndx);
2705 continue;
2706 }
2707 }
2708 }
2709 DBG_CALL(Dbg_util_nl(ofl->ofl_lml, DBG_NL_STD));
2710
2711 /*
2712 * Associate weak (alias) symbols to their non-weak counterparts by
2713 * scanning the global symbols one more time.
2714 *
2715 * This association is needed when processing the symbols from a shared
2716 * object dependency when a a weak definition satisfies a reference:
2717 *
2718 * - When building a dynamic executable, if a referenced symbol is a
2719 * data item, the symbol data is copied to the executables address
2720 * space. In this copy-relocation case, we must also reassociate
2721 * the alias symbol with its new location in the executable.
2722 *
2723 * - If the referenced symbol is a function then we may need to
2724 * promote the symbols binding from undefined weak to undefined,
2725 * otherwise the run-time linker will not generate the correct
2726 * relocation error should the symbol not be found.
2727 *
2728 * Weak alias association is also required when a local dynsym table
2729 * is being created. This table should only contain one instance of a
2730 * symbol that is associated to a given address.
2731 *
2732 * The true association between a weak/strong symbol pair is that both
2733 * symbol entries are identical, thus first we create a sorted symbol
2734 * list keyed off of the symbols section index and value. If the symbol
2735 * belongs to the same section and has the same value, then the chances
2736 * are that the rest of the symbols data is the same. This list is then
2737 * scanned for weak symbols, and if one is found then any strong
2738 * association will exist in the entries that follow. Thus we just have
2739 * to scan one (typically a single alias) or more (in the uncommon
2740 * instance of multiple weak to strong associations) entries to
2741 * determine if a match exists.
2742 */
2743 if (weak && (OFL_ALLOW_LDYNSYM(ofl) || (etype == ET_DYN)) &&
2744 (total > local)) {
2745 static Sym_desc **sort;
2746 static size_t osize = 0;
2747 size_t nsize = (total - local) * sizeof (Sym_desc *);
2748
2749 /*
2750 * As we might be processing many input files, and many symbols,
2751 * try and reuse a static sort buffer. Note, presently we're
2752 * playing the game of never freeing any buffers as there's a
2753 * belief this wastes time.
2754 */
2755 if ((osize == 0) || (nsize > osize)) {
2756 if ((sort = libld_malloc(nsize)) == NULL)
2757 return (S_ERROR);
2758 osize = nsize;
2759 }
2760 (void) memcpy((void *)sort, &ifl->ifl_oldndx[local], nsize);
2761
2762 qsort(sort, (total - local), sizeof (Sym_desc *), compare);
2763
2764 for (ndx = 0; ndx < (total - local); ndx++) {
2765 Sym_desc *wsdp = sort[ndx];
2766 Sym *wsym;
2767 int sndx;
2768
2769 /*
2770 * Ignore any empty symbol descriptor, or the case where
2771 * the symbol has been resolved to a different file.
2772 */
2773 if ((wsdp == NULL) || (wsdp->sd_file != ifl))
2774 continue;
2775
2776 wsym = wsdp->sd_sym;
2777
2778 if ((wsym->st_shndx == SHN_UNDEF) ||
2779 (wsdp->sd_flags & FLG_SY_SPECSEC) ||
2780 (ELF_ST_BIND(wsym->st_info) != STB_WEAK))
2781 continue;
2782
2783 /*
2784 * We have a weak symbol, if it has a strong alias it
2785 * will have been sorted to one of the following sort
2786 * table entries. Note that we could have multiple weak
2787 * symbols aliased to one strong (if this occurs then
2788 * the strong symbol only maintains one alias back to
2789 * the last weak).
2790 */
2791 for (sndx = ndx + 1; sndx < (total - local); sndx++) {
2792 Sym_desc *ssdp = sort[sndx];
2793 Sym *ssym;
2794 sd_flag_t w_dynbits, s_dynbits;
2795
2796 /*
2797 * Ignore any empty symbol descriptor, or the
2798 * case where the symbol has been resolved to a
2799 * different file.
2800 */
2801 if ((ssdp == NULL) || (ssdp->sd_file != ifl))
2802 continue;
2803
2804 ssym = ssdp->sd_sym;
2805
2806 if (ssym->st_shndx == SHN_UNDEF)
2807 continue;
2808
2809 if ((ssym->st_shndx != wsym->st_shndx) ||
2810 (ssym->st_value != wsym->st_value))
2811 break;
2812
2813 if ((ssym->st_size != wsym->st_size) ||
2814 (ssdp->sd_flags & FLG_SY_SPECSEC) ||
2815 (ELF_ST_BIND(ssym->st_info) == STB_WEAK))
2816 continue;
2817
2818 /*
2819 * If a sharable object, set link fields so
2820 * that they reference each other.`
2821 */
2822 if (etype == ET_DYN) {
2823 ssdp->sd_aux->sa_linkndx =
2824 (Word)wsdp->sd_symndx;
2825 wsdp->sd_aux->sa_linkndx =
2826 (Word)ssdp->sd_symndx;
2827 }
2828
2829 /*
2830 * Determine which of these two symbols go into
2831 * the sort section. If a mapfile has made
2832 * explicit settings of the FLG_SY_*DYNSORT
2833 * flags for both symbols, then we do what they
2834 * say. If one has the DYNSORT flags set, we
2835 * set the NODYNSORT bit in the other. And if
2836 * neither has an explicit setting, then we
2837 * favor the weak symbol because they usually
2838 * lack the leading underscore.
2839 */
2840 w_dynbits = wsdp->sd_flags &
2841 (FLG_SY_DYNSORT | FLG_SY_NODYNSORT);
2842 s_dynbits = ssdp->sd_flags &
2843 (FLG_SY_DYNSORT | FLG_SY_NODYNSORT);
2844 if (!(w_dynbits && s_dynbits)) {
2845 if (s_dynbits) {
2846 if (s_dynbits == FLG_SY_DYNSORT)
2847 wsdp->sd_flags |=
2848 FLG_SY_NODYNSORT;
2849 } else if (w_dynbits !=
2850 FLG_SY_NODYNSORT) {
2851 ssdp->sd_flags |=
2852 FLG_SY_NODYNSORT;
2853 }
2854 }
2855 break;
2856 }
2857 }
2858 }
2859
2860 /*
2861 * Having processed all symbols, under -z symbolcap, reprocess any
2862 * symbols that are being translated from global to locals. The symbol
2863 * pair that has been collected defines the original symbol (c_osdp),
2864 * which will become a local, and the new symbol (c_nsdp), which will
2865 * become a reference (UNDEF) for the original.
2866 *
2867 * Scan these symbol pairs looking for weak symbols, which have non-weak
2868 * aliases. There is no need to translate both of these symbols to
2869 * locals, only the global is necessary.
2870 */
2871 if (cappairs) {
2872 Aliste idx1;
2873 Cap_pair *cpp1;
2874
2875 for (ALIST_TRAVERSE(cappairs, idx1, cpp1)) {
2876 Sym_desc *sdp1 = cpp1->c_osdp;
2877 Sym *sym1 = sdp1->sd_sym;
2878 uchar_t bind1 = ELF_ST_BIND(sym1->st_info);
2879 Aliste idx2;
2880 Cap_pair *cpp2;
2881
2882 /*
2883 * If this symbol isn't weak, it's capability member is
2884 * retained for the creation of a local symbol.
2885 */
2886 if (bind1 != STB_WEAK)
2887 continue;
2888
2889 /*
2890 * If this is a weak symbol, traverse the capabilities
2891 * list again to determine if a corresponding non-weak
2892 * symbol exists.
2893 */
2894 for (ALIST_TRAVERSE(cappairs, idx2, cpp2)) {
2895 Sym_desc *sdp2 = cpp2->c_osdp;
2896 Sym *sym2 = sdp2->sd_sym;
2897 uchar_t bind2 =
2898 ELF_ST_BIND(sym2->st_info);
2899
2900 if ((cpp1 == cpp2) ||
2901 (cpp1->c_group != cpp2->c_group) ||
2902 (sym1->st_value != sym2->st_value) ||
2903 (bind2 == STB_WEAK))
2904 continue;
2905
2906 /*
2907 * The weak symbol (sym1) has a non-weak (sym2)
2908 * counterpart. There's no point in translating
2909 * both of these equivalent symbols to locals.
2910 * Add this symbol capability alias to the
2911 * capabilities family information, and remove
2912 * the weak symbol.
2913 */
2914 if (ld_cap_add_family(ofl, cpp2->c_nsdp,
2915 cpp1->c_nsdp, NULL, NULL) == S_ERROR)
2916 return (S_ERROR);
2917
2918 free((void *)cpp1->c_osdp);
2919 (void) alist_delete(cappairs, &idx1);
2920 }
2921 }
2922
2923 DBG_CALL(Dbg_util_nl(ofl->ofl_lml, DBG_NL_STD));
2924
2925 /*
2926 * The capability pairs information now represents all the
2927 * global symbols that need transforming to locals. These
2928 * local symbols are renamed using their group identifiers.
2929 */
2930 for (ALIST_TRAVERSE(cappairs, idx1, cpp1)) {
2931 Sym_desc *osdp = cpp1->c_osdp;
2932 Objcapset *capset;
2933 size_t nsize, tsize;
2934 const char *oname;
2935 char *cname, *idstr;
2936 Sym *csym;
2937
2938 /*
2939 * If the local symbol has not yet been translated
2940 * convert it to a local symbol with a name.
2941 */
2942 if ((osdp->sd_flags & FLG_SY_CAP) != 0)
2943 continue;
2944
2945 /*
2946 * As we're converting object capabilities to symbol
2947 * capabilities, obtain the capabilities set for this
2948 * object, so as to retrieve the CA_SUNW_ID value.
2949 */
2950 capset = &cpp1->c_group->cg_set;
2951
2952 /*
2953 * Create a new name from the existing symbol and the
2954 * capabilities group identifier. Note, the delimiter
2955 * between the symbol name and identifier name is hard-
2956 * coded here (%), so that we establish a convention
2957 * for transformed symbol names.
2958 */
2959 oname = osdp->sd_name;
2960
2961 idstr = capset->oc_id.cs_str;
2962 nsize = strlen(oname);
2963 tsize = nsize + 1 + strlen(idstr) + 1;
2964 if ((cname = libld_malloc(tsize)) == 0)
2965 return (S_ERROR);
2966
2967 (void) strcpy(cname, oname);
2968 cname[nsize++] = '%';
2969 (void) strcpy(&cname[nsize], idstr);
2970
2971 /*
2972 * Allocate a new symbol table entry, transform this
2973 * symbol to a local, and assign the new name.
2974 */
2975 if ((csym = libld_malloc(sizeof (Sym))) == NULL)
2976 return (S_ERROR);
2977
2978 *csym = *osdp->sd_sym;
2979 csym->st_info = ELF_ST_INFO(STB_LOCAL,
2980 ELF_ST_TYPE(osdp->sd_sym->st_info));
2981
2982 osdp->sd_name = cname;
2983 osdp->sd_sym = csym;
2984 osdp->sd_flags = FLG_SY_CAP;
2985
2986 /*
2987 * Keep track of this new local symbol. As -z symbolcap
2988 * can only be used to create a relocatable object, a
2989 * dynamic symbol table can't exist. Ensure there is
2990 * space reserved in the string table.
2991 */
2992 ofl->ofl_caploclcnt++;
2993 if (st_insert(ofl->ofl_strtab, cname) == -1)
2994 return (S_ERROR);
2995
2996 DBG_CALL(Dbg_syms_cap_local(ofl, cpp1->c_ndx,
2997 cname, csym, osdp));
2998
2999 /*
3000 * Establish this capability pair as a family.
3001 */
3002 if (ld_cap_add_family(ofl, cpp1->c_nsdp, osdp,
3003 cpp1->c_group, &ifl->ifl_caps->ca_syms) == S_ERROR)
3004 return (S_ERROR);
3005 }
3006 }
3007
3008 return (1);
3009
3010 #undef SYM_LOC_BADADDR
3011 }
3012
3013 /*
3014 * Add an undefined symbol to the symbol table. The reference originates from
3015 * the location identified by the message id (mid). These references can
3016 * originate from command line options such as -e, -u, -initarray, etc.
3017 * (identified with MSG_INTL(MSG_STR_COMMAND)), or from internally generated
3018 * TLS relocation references (identified with MSG_INTL(MSG_STR_TLSREL)).
3019 */
3020 Sym_desc *
3021 ld_sym_add_u(const char *name, Ofl_desc *ofl, Msg mid)
3022 {
3023 Sym *sym;
3024 Ifl_desc *ifl = NULL, *_ifl;
3025 Sym_desc *sdp;
3026 Word hash;
3027 Aliste idx;
3028 avl_index_t where;
3029 const char *reference = MSG_INTL(mid);
3030
3031 /*
3032 * As an optimization, determine whether we've already generated this
3033 * reference. If the symbol doesn't already exist we'll create it.
3034 * Or if the symbol does exist from a different source, we'll resolve
3035 * the conflict.
3036 */
3037 /* LINTED */
3038 hash = (Word)elf_hash(name);
3039 if ((sdp = ld_sym_find(name, hash, &where, ofl)) != NULL) {
3040 if ((sdp->sd_sym->st_shndx == SHN_UNDEF) &&
3041 (sdp->sd_file->ifl_name == reference))
3042 return (sdp);
3043 }
3044
3045 /*
3046 * Determine whether a pseudo input file descriptor exists to represent
3047 * the command line, as any global symbol needs an input file descriptor
3048 * during any symbol resolution (refer to map_ifl() which provides a
3049 * similar method for adding symbols from mapfiles).
3050 */
3051 for (APLIST_TRAVERSE(ofl->ofl_objs, idx, _ifl))
3052 if (strcmp(_ifl->ifl_name, reference) == 0) {
3053 ifl = _ifl;
3054 break;
3055 }
3056
3057 /*
3058 * If no descriptor exists create one.
3059 */
3060 if (ifl == NULL) {
3061 if ((ifl = libld_calloc(sizeof (Ifl_desc), 1)) == NULL)
3062 return ((Sym_desc *)S_ERROR);
3063 ifl->ifl_name = reference;
3064 ifl->ifl_flags = FLG_IF_NEEDED | FLG_IF_FILEREF;
3065 if ((ifl->ifl_ehdr = libld_calloc(sizeof (Ehdr), 1)) == NULL)
3066 return ((Sym_desc *)S_ERROR);
3067 ifl->ifl_ehdr->e_type = ET_REL;
3068
3069 if (aplist_append(&ofl->ofl_objs, ifl, AL_CNT_OFL_OBJS) == NULL)
3070 return ((Sym_desc *)S_ERROR);
3071 }
3072
3073 /*
3074 * Allocate a symbol structure and add it to the global symbol table.
3075 */
3076 if ((sym = libld_calloc(sizeof (Sym), 1)) == NULL)
3077 return ((Sym_desc *)S_ERROR);
3078 sym->st_info = ELF_ST_INFO(STB_GLOBAL, STT_NOTYPE);
3079 sym->st_shndx = SHN_UNDEF;
3080
3081 DBG_CALL(Dbg_syms_process(ofl->ofl_lml, ifl));
3082 if (sdp == NULL) {
3083 DBG_CALL(Dbg_syms_global(ofl->ofl_lml, 0, name));
3084 if ((sdp = ld_sym_enter(name, sym, hash, ifl, ofl, 0, SHN_UNDEF,
3085 0, &where)) == (Sym_desc *)S_ERROR)
3086 return ((Sym_desc *)S_ERROR);
3087 } else if (ld_sym_resolve(sdp, sym, ifl, ofl, 0,
3088 SHN_UNDEF, 0) == S_ERROR)
3089 return ((Sym_desc *)S_ERROR);
3090
3091 sdp->sd_flags &= ~FLG_SY_CLEAN;
3092 sdp->sd_flags |= FLG_SY_CMDREF;
3093
3094 return (sdp);
3095 }
3096
3097 /*
3098 * STT_SECTION symbols have their st_name field set to NULL, and consequently
3099 * have no name. Generate a name suitable for diagnostic use for such a symbol
3100 * and store it in the input section descriptor. The resulting name will be
3101 * of the form:
3102 *
3103 * "XXX (section)"
3104 *
3105 * where XXX is the name of the section.
3106 *
3107 * entry:
3108 * isc - Input section associated with the symbol.
3109 * fmt - NULL, or format string to use.
3110 *
3111 * exit:
3112 * Sets isp->is_sym_name to the allocated string. Returns the
3113 * string pointer, or NULL on allocation failure.
3114 */
3115 const char *
3116 ld_stt_section_sym_name(Is_desc *isp)
3117 {
3118 const char *fmt;
3119 char *str;
3120 size_t len;
3121
3122 if ((isp == NULL) || (isp->is_name == NULL))
3123 return (NULL);
3124
3125 if (isp->is_sym_name == NULL) {
3126 fmt = (isp->is_flags & FLG_IS_GNSTRMRG) ?
3127 MSG_INTL(MSG_STR_SECTION_MSTR) : MSG_INTL(MSG_STR_SECTION);
3128
3129 len = strlen(fmt) + strlen(isp->is_name) + 1;
3130
3131 if ((str = libld_malloc(len)) == NULL)
3132 return (NULL);
3133 (void) snprintf(str, len, fmt, isp->is_name);
3134 isp->is_sym_name = str;
3135 }
3136
3137 return (isp->is_sym_name);
3138 }
3139
3140 /*
3141 * If we're producing a relocatable object and the symbol is eligible for
3142 * COMDAT section, it shouldn't be reduced in scope as that will break the
3143 * COMDAT matching when the output object is later consumed. Leave it alone,
3144 * and any reduction (and COMDAT) processing will occur then.
3145 *
3146 * Otherwise, any hidden symbol is reduced when reductions are being processed.
3147 */
3148 Boolean
3149 ld_sym_reducable(Ofl_desc *ofl, Sym_desc *sdp)
3150 {
3151 Is_desc *isc = sdp->sd_isc;
3152
3153 if (((ofl->ofl_flags & FLG_OF_RELOBJ) != 0) &&
3154 (isc != NULL) &&
3155 ((isc->is_flags & FLG_IS_COMDAT) != 0)) {
3156 return (FALSE);
3157 } else {
3158 return (SYM_IS_HIDDEN(sdp) &&
3159 (ofl->ofl_flags & FLG_OF_PROCRED));
3160 }
3161 }