xref: /illumos-gate/usr/src/cmd/sgs/rtld/common/elf.c (revision 48011479)
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  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
27  * Use is subject to license terms.
28  */
29 #pragma ident	"%Z%%M%	%I%	%E% SMI"
30 
31 /*
32  * Object file dependent support for ELF objects.
33  */
34 #include	"_synonyms.h"
35 
36 #include	<stdio.h>
37 #include	<sys/procfs.h>
38 #include	<sys/mman.h>
39 #include	<sys/debug.h>
40 #include	<string.h>
41 #include	<limits.h>
42 #include	<dlfcn.h>
43 #include	<debug.h>
44 #include	<conv.h>
45 #include	"_rtld.h"
46 #include	"_audit.h"
47 #include	"_elf.h"
48 #include	"msg.h"
49 
50 /*
51  * Default and secure dependency search paths.
52  */
53 static Pnode		elf_dflt_dirs[] = {
54 #if	defined(_ELF64)
55 #ifndef	SGS_PRE_UNIFIED_PROCESS
56 	{ MSG_ORIG(MSG_PTH_LIB_64),		0,	MSG_PTH_LIB_64_SIZE,
57 		LA_SER_DEFAULT,			0,	&elf_dflt_dirs[1] },
58 #endif
59 	{ MSG_ORIG(MSG_PTH_USRLIB_64),		0,	MSG_PTH_USRLIB_64_SIZE,
60 		LA_SER_DEFAULT,			0, 0 }
61 #else
62 #ifndef	SGS_PRE_UNIFIED_PROCESS
63 	{ MSG_ORIG(MSG_PTH_LIB),		0,	MSG_PTH_LIB_SIZE,
64 		LA_SER_DEFAULT,			0,	&elf_dflt_dirs[1] },
65 #endif
66 	{ MSG_ORIG(MSG_PTH_USRLIB),		0,	MSG_PTH_USRLIB_SIZE,
67 		LA_SER_DEFAULT,			0, 0 }
68 #endif
69 };
70 
71 static Pnode		elf_secure_dirs[] = {
72 #if	defined(_ELF64)
73 #ifndef	SGS_PRE_UNIFIED_PROCESS
74 	{ MSG_ORIG(MSG_PTH_LIBSE_64),		0,	MSG_PTH_LIBSE_64_SIZE,
75 		LA_SER_SECURE,			0,	&elf_secure_dirs[1] },
76 #endif
77 	{ MSG_ORIG(MSG_PTH_USRLIBSE_64),	0,
78 		MSG_PTH_USRLIBSE_64_SIZE,
79 		LA_SER_SECURE,			0, 0 }
80 #else
81 #ifndef	SGS_PRE_UNIFIED_PROCESS
82 	{ MSG_ORIG(MSG_PTH_LIBSE),		0,	MSG_PTH_LIBSE_SIZE,
83 		LA_SER_SECURE,			0,	&elf_secure_dirs[1] },
84 #endif
85 	{ MSG_ORIG(MSG_PTH_USRLIBSE),		0,	MSG_PTH_USRLIBSE_SIZE,
86 		LA_SER_SECURE,			0, 0 }
87 #endif
88 };
89 
90 /*
91  * Defines for local functions.
92  */
93 static Pnode	*elf_fix_name(const char *, Rt_map *, uint_t);
94 static int	elf_are_u(Rej_desc *);
95 static void	elf_dladdr(ulong_t, Rt_map *, Dl_info *, void **, int);
96 static ulong_t	elf_entry_pt(void);
97 static char	*elf_get_so(const char *, const char *);
98 static Rt_map	*elf_map_so(Lm_list *, Aliste, const char *, const char *, int);
99 static int	elf_needed(Lm_list *, Aliste, Rt_map *);
100 static void	elf_unmap_so(Rt_map *);
101 static int	elf_verify_vers(const char *, Rt_map *, Rt_map *);
102 
103 /*
104  * Functions and data accessed through indirect pointers.
105  */
106 Fct elf_fct = {
107 	elf_are_u,
108 	elf_entry_pt,
109 	elf_map_so,
110 	elf_unmap_so,
111 	elf_needed,
112 	lookup_sym,
113 	elf_reloc,
114 	elf_dflt_dirs,
115 	elf_secure_dirs,
116 	elf_fix_name,
117 	elf_get_so,
118 	elf_dladdr,
119 	dlsym_handle,
120 	elf_verify_vers,
121 	elf_set_prot
122 };
123 
124 
125 /*
126  * Redefine NEEDED name if necessary.
127  */
128 static Pnode *
129 elf_fix_name(const char *name, Rt_map *clmp, uint_t orig)
130 {
131 	/*
132 	 * For ABI compliance, if we are asked for ld.so.1, then really give
133 	 * them libsys.so.1 (the SONAME of libsys.so.1 is ld.so.1).
134 	 */
135 	if (((*name == '/') &&
136 #if	defined(_ELF64)
137 	    (strcmp(name, MSG_ORIG(MSG_PTH_RTLD_64)) == 0)) ||
138 #else
139 	    (strcmp(name, MSG_ORIG(MSG_PTH_RTLD)) == 0)) ||
140 #endif
141 	    (strcmp(name, MSG_ORIG(MSG_FIL_RTLD)) == 0)) {
142 		Pnode	*pnp;
143 
144 		DBG_CALL(Dbg_file_fixname(LIST(clmp), name,
145 		    MSG_ORIG(MSG_PTH_LIBSYS)));
146 		if (((pnp = calloc(sizeof (Pnode), 1)) == 0) ||
147 		    ((pnp->p_name = strdup(MSG_ORIG(MSG_PTH_LIBSYS))) == 0)) {
148 			if (pnp)
149 				free(pnp);
150 			return (0);
151 		}
152 		pnp->p_len = MSG_PTH_LIBSYS_SIZE;
153 		pnp->p_orig = (orig & PN_SER_MASK);
154 		return (pnp);
155 	}
156 
157 	return (expand_paths(clmp, name, orig, 0));
158 }
159 
160 /*
161  * Determine if we have been given an ELF file and if so determine if the file
162  * is compatible.  Returns 1 if true, else 0 and sets the reject descriptor
163  * with associated error information.
164  */
165 static int
166 elf_are_u(Rej_desc *rej)
167 {
168 	Ehdr	*ehdr;
169 
170 	/*
171 	 * Determine if we're an elf file.  If not simply return, we don't set
172 	 * any rejection information as this test allows use to scroll through
173 	 * the objects we support (ELF, AOUT).
174 	 */
175 	if (fmap->fm_fsize < sizeof (Ehdr) ||
176 	    fmap->fm_maddr[EI_MAG0] != ELFMAG0 ||
177 	    fmap->fm_maddr[EI_MAG1] != ELFMAG1 ||
178 	    fmap->fm_maddr[EI_MAG2] != ELFMAG2 ||
179 	    fmap->fm_maddr[EI_MAG3] != ELFMAG3) {
180 		return (0);
181 	}
182 
183 	/*
184 	 * Check class and encoding.
185 	 */
186 	/* LINTED */
187 	ehdr = (Ehdr *)fmap->fm_maddr;
188 	if (ehdr->e_ident[EI_CLASS] != M_CLASS) {
189 		rej->rej_type = SGS_REJ_CLASS;
190 		rej->rej_info = (uint_t)ehdr->e_ident[EI_CLASS];
191 		return (0);
192 	}
193 	if (ehdr->e_ident[EI_DATA] != M_DATA) {
194 		rej->rej_type = SGS_REJ_DATA;
195 		rej->rej_info = (uint_t)ehdr->e_ident[EI_DATA];
196 		return (0);
197 	}
198 	if ((ehdr->e_type != ET_REL) && (ehdr->e_type != ET_EXEC) &&
199 	    (ehdr->e_type != ET_DYN)) {
200 		rej->rej_type = SGS_REJ_TYPE;
201 		rej->rej_info = (uint_t)ehdr->e_type;
202 		return (0);
203 	}
204 
205 	/*
206 	 * Verify machine specific flags, and hardware capability requirements.
207 	 */
208 	if ((elf_mach_flags_check(rej, ehdr) == 0) ||
209 	    ((rtld_flags2 & RT_FL2_HWCAP) && (hwcap_check(rej, ehdr) == 0)))
210 		return (0);
211 
212 	/*
213 	 * Verify ELF version.  ??? is this too restrictive ???
214 	 */
215 	if (ehdr->e_version > EV_CURRENT) {
216 		rej->rej_type = SGS_REJ_VERSION;
217 		rej->rej_info = (uint_t)ehdr->e_version;
218 		return (0);
219 	}
220 	return (1);
221 }
222 
223 /*
224  * The runtime linker employs lazy loading to provide the libraries needed for
225  * debugging, preloading .o's and dldump().  As these are seldom used, the
226  * standard startup of ld.so.1 doesn't initialize all the information necessary
227  * to perform plt relocation on ld.so.1's link-map.  The first time lazy loading
228  * is called we get here to perform these initializations:
229  *
230  *  o	elf_needed() is called to set up the DYNINFO() indexes for each lazy
231  *	dependency.  Typically, for all other objects, this is called during
232  *	analyze_so(), but as ld.so.1 is set-contained we skip this processing.
233  *
234  *  o	For intel, ld.so.1's JMPSLOT relocations need relative updates. These
235  *	are by default skipped thus delaying all relative relocation processing
236  * 	on every invocation of ld.so.1.
237  */
238 int
239 elf_rtld_load()
240 {
241 	Lm_list	*lml = &lml_rtld;
242 	Rt_map	*lmp = lml->lm_head;
243 
244 	if (lml->lm_flags & LML_FLG_PLTREL)
245 		return (1);
246 
247 	/*
248 	 * As we need to refer to the DYNINFO() information, insure that it has
249 	 * been initialized.
250 	 */
251 	if (elf_needed(lml, ALO_DATA, lmp) == 0)
252 		return (0);
253 
254 #if	defined(__i386)
255 	/*
256 	 * This is a kludge to give ld.so.1 a performance benefit on i386.
257 	 * It's based around two factors.
258 	 *
259 	 *  o	JMPSLOT relocations (PLT's) actually need a relative relocation
260 	 *	applied to the GOT entry so that they can find PLT0.
261 	 *
262 	 *  o	ld.so.1 does not exercise *any* PLT's before it has made a call
263 	 *	to elf_lazy_load().  This is because all dynamic dependencies
264 	 * 	are recorded as lazy dependencies.
265 	 */
266 	(void) elf_reloc_relacount((ulong_t)JMPREL(lmp),
267 	    (ulong_t)(PLTRELSZ(lmp) / RELENT(lmp)), (ulong_t)RELENT(lmp),
268 	    (ulong_t)ADDR(lmp));
269 #endif
270 
271 	lml->lm_flags |= LML_FLG_PLTREL;
272 	return (1);
273 }
274 
275 /*
276  * Lazy load an object.
277  */
278 Rt_map *
279 elf_lazy_load(Rt_map *clmp, uint_t ndx, const char *sym)
280 {
281 	Rt_map		*nlmp, *hlmp;
282 	Dyninfo		*dip = &DYNINFO(clmp)[ndx];
283 	uint_t		flags = 0;
284 	Pnode		*pnp;
285 	const char	*name;
286 	Lm_list		*lml = LIST(clmp);
287 	Lm_cntl		*lmc;
288 	Aliste		lmco;
289 
290 	/*
291 	 * If this dependency has already been processed, we're done.
292 	 */
293 	if (((nlmp = (Rt_map *)dip->di_info) != 0) ||
294 	    (dip->di_flags & FLG_DI_PROCESSD))
295 		return (nlmp);
296 
297 	/*
298 	 * Determine the initial dependency name, and indicate that this
299 	 * dependencies processing has initiated.
300 	 */
301 	name = STRTAB(clmp) + DYN(clmp)[ndx].d_un.d_val;
302 	DBG_CALL(Dbg_file_lazyload(clmp, name, sym));
303 	if (lml->lm_flags & LML_FLG_TRC_ENABLE)
304 		dip->di_flags |= FLG_DI_PROCESSD;
305 
306 	if (dip->di_flags & FLG_DI_GROUP)
307 		flags |= (FLG_RT_SETGROUP | FLG_RT_HANDLE);
308 
309 	/*
310 	 * Expand the requested name if necessary.
311 	 */
312 	if ((pnp = elf_fix_name(name, clmp, PN_SER_NEEDED)) == 0)
313 		return (0);
314 
315 	/*
316 	 * Provided the object on the head of the link-map has completed its
317 	 * relocation, create a new link-map control list for this request.
318 	 */
319 	hlmp = lml->lm_head;
320 	if (FLAGS(hlmp) & FLG_RT_RELOCED) {
321 		if ((lmc = alist_append(&(lml->lm_lists), 0, sizeof (Lm_cntl),
322 		    AL_CNT_LMLISTS)) == 0) {
323 			remove_pnode(pnp);
324 			return (0);
325 		}
326 		lmco = (Aliste)((char *)lmc - (char *)lml->lm_lists);
327 	} else {
328 		lmc = 0;
329 		lmco = ALO_DATA;
330 	}
331 
332 	/*
333 	 * Load the associated object.
334 	 */
335 	dip->di_info = nlmp =
336 	    load_one(lml, lmco, pnp, clmp, MODE(clmp), flags, 0);
337 
338 	/*
339 	 * Remove any expanded pathname infrastructure.  Reduce the pending lazy
340 	 * dependency count of the caller, together with the link-map lists
341 	 * count of objects that still have lazy dependencies pending.
342 	 */
343 	remove_pnode(pnp);
344 	if (--LAZY(clmp) == 0)
345 		LIST(clmp)->lm_lazy--;
346 
347 	/*
348 	 * Finish processing the objects associated with this request, and
349 	 * create an association between the caller and this dependency.
350 	 */
351 	if (nlmp && (((analyze_lmc(lml, lmco, nlmp) == 0)) ||
352 	    (relocate_lmc(lml, lmco, clmp, nlmp) == 0) ||
353 	    (bind_one(clmp, nlmp, BND_NEEDED) == 0)))
354 		dip->di_info = nlmp = 0;
355 
356 	/*
357 	 * If this lazyload has failed, and we've created a new link-map
358 	 * control list to which this request has added objects, then remove
359 	 * all the objects that have been associated to this request.
360 	 */
361 	if ((nlmp == 0) && lmc && lmc->lc_head)
362 		remove_lmc(lml, clmp, lmc, lmco, name);
363 
364 	/*
365 	 * Finally, remove any link-map control list that was created.
366 	 */
367 	if (lmc)
368 		remove_cntl(lml, lmco);
369 
370 	return (nlmp);
371 }
372 
373 /*
374  * Return the entry point of the ELF executable.
375  */
376 static ulong_t
377 elf_entry_pt(void)
378 {
379 	return (ENTRY(lml_main.lm_head));
380 }
381 
382 /*
383  * Unmap a given ELF shared object from the address space.
384  */
385 static void
386 elf_unmap_so(Rt_map *lmp)
387 {
388 	caddr_t	addr;
389 	size_t	size;
390 	Mmap	*mmaps;
391 
392 	/*
393 	 * If this link map represents a relocatable object concatenation, then
394 	 * the image was simply generated in allocated memory.  Free the memory.
395 	 *
396 	 * Note: the memory was originally allocated in the libelf:_elf_outmap
397 	 * routine and would normally have been free'd in elf_outsync(), but
398 	 * because we 'interpose' on that routine the memory  wasn't free'd at
399 	 * that time.
400 	 */
401 	if (FLAGS(lmp) & FLG_RT_IMGALLOC) {
402 		free((void *)ADDR(lmp));
403 		return;
404 	}
405 
406 	/*
407 	 * If padding was enabled via rtld_db, then we have at least one page
408 	 * in front of the image - and possibly a trailing page.
409 	 * Unmap the front page first:
410 	 */
411 	if (PADSTART(lmp) != ADDR(lmp)) {
412 		addr = (caddr_t)M_PTRUNC(PADSTART(lmp));
413 		size = ADDR(lmp) - (ulong_t)addr;
414 		(void) munmap(addr, size);
415 	}
416 
417 	/*
418 	 * Unmap any trailing padding.
419 	 */
420 	if (M_PROUND((PADSTART(lmp) + PADIMLEN(lmp))) >
421 	    M_PROUND(ADDR(lmp) + MSIZE(lmp))) {
422 		addr = (caddr_t)M_PROUND(ADDR(lmp) + MSIZE(lmp));
423 		size = M_PROUND(PADSTART(lmp) + PADIMLEN(lmp)) - (ulong_t)addr;
424 		(void) munmap(addr, size);
425 	}
426 
427 	/*
428 	 * Unmmap all mapped segments.
429 	 */
430 	for (mmaps = MMAPS(lmp); mmaps->m_vaddr; mmaps++)
431 		(void) munmap(mmaps->m_vaddr, mmaps->m_msize);
432 }
433 
434 /*
435  * Determine if a dependency requires a particular version and if so verify
436  * that the version exists in the dependency.
437  */
438 static int
439 elf_verify_vers(const char *name, Rt_map *clmp, Rt_map *nlmp)
440 {
441 	Verneed		*vnd = VERNEED(clmp);
442 	int		_num, num = VERNEEDNUM(clmp);
443 	char		*cstrs = (char *)STRTAB(clmp);
444 	Lm_list		*lml = LIST(clmp);
445 
446 	/*
447 	 * Traverse the callers version needed information and determine if any
448 	 * specific versions are required from the dependency.
449 	 */
450 	DBG_CALL(Dbg_ver_need_title(LIST(clmp), NAME(clmp)));
451 	for (_num = 1; _num <= num; _num++,
452 	    vnd = (Verneed *)((Xword)vnd + vnd->vn_next)) {
453 		Half		cnt = vnd->vn_cnt;
454 		Vernaux		*vnap;
455 		char		*nstrs, *need;
456 
457 		/*
458 		 * Determine if a needed entry matches this dependency.
459 		 */
460 		need = (char *)(cstrs + vnd->vn_file);
461 		if (strcmp(name, need) != 0)
462 			continue;
463 
464 		if ((lml->lm_flags & LML_FLG_TRC_VERBOSE) &&
465 		    ((FLAGS1(clmp) & FL1_RT_LDDSTUB) == 0))
466 			(void) printf(MSG_INTL(MSG_LDD_VER_FIND), name);
467 
468 		/*
469 		 * Validate that each version required actually exists in the
470 		 * dependency.
471 		 */
472 		nstrs = (char *)STRTAB(nlmp);
473 
474 		for (vnap = (Vernaux *)((Xword)vnd + vnd->vn_aux); cnt;
475 		    cnt--, vnap = (Vernaux *)((Xword)vnap + vnap->vna_next)) {
476 			char		*version, *define;
477 			Verdef		*vdf = VERDEF(nlmp);
478 			ulong_t		_num, num = VERDEFNUM(nlmp);
479 			int		found = 0;
480 
481 			version = (char *)(cstrs + vnap->vna_name);
482 			DBG_CALL(Dbg_ver_need_entry(lml, 0, need, version));
483 
484 			for (_num = 1; _num <= num; _num++,
485 			    vdf = (Verdef *)((Xword)vdf + vdf->vd_next)) {
486 				Verdaux		*vdap;
487 
488 				if (vnap->vna_hash != vdf->vd_hash)
489 					continue;
490 
491 				vdap = (Verdaux *)((Xword)vdf + vdf->vd_aux);
492 				define = (char *)(nstrs + vdap->vda_name);
493 				if (strcmp(version, define) != 0)
494 					continue;
495 
496 				found++;
497 				break;
498 			}
499 
500 			/*
501 			 * If we're being traced print out any matched version
502 			 * when the verbose (-v) option is in effect.  Always
503 			 * print any unmatched versions.
504 			 */
505 			if (lml->lm_flags & LML_FLG_TRC_ENABLE) {
506 				if (found) {
507 				    if (!(lml->lm_flags & LML_FLG_TRC_VERBOSE))
508 					continue;
509 
510 				    (void) printf(MSG_ORIG(MSG_LDD_VER_FOUND),
511 					need, version, NAME(nlmp));
512 				} else {
513 				    if (rtld_flags & RT_FL_SILENCERR)
514 					continue;
515 
516 				    (void) printf(MSG_INTL(MSG_LDD_VER_NFOUND),
517 					need, version);
518 				}
519 				continue;
520 			}
521 
522 			/*
523 			 * If the version hasn't been found then this is a
524 			 * candidate for a fatal error condition.  Weak
525 			 * version definition requirements are silently
526 			 * ignored.  Also, if the image inspected for a version
527 			 * definition has no versioning recorded at all then
528 			 * silently ignore this (this provides better backward
529 			 * compatibility to old images created prior to
530 			 * versioning being available).  Both of these skipped
531 			 * diagnostics are available under tracing (see above).
532 			 */
533 			if ((found == 0) && (num != 0) &&
534 			    (!(vnap->vna_flags & VER_FLG_WEAK))) {
535 				eprintf(lml, ERR_FATAL,
536 				    MSG_INTL(MSG_VER_NFOUND), need, version,
537 				    NAME(clmp));
538 				return (0);
539 			}
540 		}
541 	}
542 	DBG_CALL(Dbg_util_nl(lml, DBG_NL_STD));
543 	return (1);
544 }
545 
546 /*
547  * Search through the dynamic section for DT_NEEDED entries and perform one
548  * of two functions.  If only the first argument is specified then load the
549  * defined shared object, otherwise add the link map representing the defined
550  * link map the the dlopen list.
551  */
552 static int
553 elf_needed(Lm_list *lml, Aliste lmco, Rt_map *clmp)
554 {
555 	Dyn		*dyn;
556 	ulong_t		ndx = 0;
557 	uint_t		lazy = 0, flags = 0;
558 	Word		lmflags = lml->lm_flags;
559 	Word		lmtflags = lml->lm_tflags;
560 
561 	/*
562 	 * Process each shared object on needed list.
563 	 */
564 	if (DYN(clmp) == 0)
565 		return (1);
566 
567 	for (dyn = (Dyn *)DYN(clmp); dyn->d_tag != DT_NULL; dyn++, ndx++) {
568 		Dyninfo	*dip = &DYNINFO(clmp)[ndx];
569 		Rt_map	*nlmp = 0;
570 		char	*name;
571 		int	silent = 0;
572 		Pnode	*pnp;
573 
574 		switch (dyn->d_tag) {
575 		case DT_POSFLAG_1:
576 			if ((dyn->d_un.d_val & DF_P1_LAZYLOAD) &&
577 			    !(lmtflags & LML_TFLG_NOLAZYLD))
578 				lazy = 1;
579 			if (dyn->d_un.d_val & DF_P1_GROUPPERM)
580 				flags = (FLG_RT_SETGROUP | FLG_RT_HANDLE);
581 			continue;
582 		case DT_NEEDED:
583 		case DT_USED:
584 			dip->di_flags |= FLG_DI_NEEDED;
585 			if (flags)
586 				dip->di_flags |= FLG_DI_GROUP;
587 
588 			name = (char *)STRTAB(clmp) + dyn->d_un.d_val;
589 
590 			/*
591 			 * NOTE, libc.so.1 can't be lazy loaded.  Although a
592 			 * lazy position flag won't be produced when a RTLDINFO
593 			 * .dynamic entry is found (introduced with the UPM in
594 			 * Solaris 10), it was possible to mark libc for lazy
595 			 * loading on previous releases.  To reduce the overhead
596 			 * of testing for this occurrence, only carry out this
597 			 * check for the first object on the link-map list
598 			 * (there aren't many applications built without libc).
599 			 */
600 			if (lazy && (lml->lm_head == clmp) &&
601 			    (strcmp(name, MSG_ORIG(MSG_FIL_LIBC)) == 0))
602 				lazy = 0;
603 
604 			/*
605 			 * Don't bring in lazy loaded objects yet unless we've
606 			 * been asked to attempt to load all available objects
607 			 * (crle(1) sets LD_FLAGS=loadavail).  Even under
608 			 * RTLD_NOW we don't process this - RTLD_NOW will cause
609 			 * relocation processing which in turn might trigger
610 			 * lazy loading, but its possible that the object has a
611 			 * lazy loaded file with no bindings (i.e., it should
612 			 * never have been a dependency in the first place).
613 			 */
614 			if (lazy) {
615 				if ((lmflags & LML_FLG_LOADAVAIL) == 0) {
616 					LAZY(clmp)++;
617 					lazy = flags = 0;
618 					continue;
619 				}
620 
621 				/*
622 				 * Silence any error messages - see description
623 				 * under elf_lookup_filtee().
624 				 */
625 				if ((rtld_flags & RT_FL_SILENCERR) == 0) {
626 					rtld_flags |= RT_FL_SILENCERR;
627 					silent = 1;
628 				}
629 			}
630 			break;
631 		case DT_AUXILIARY:
632 			dip->di_flags |= FLG_DI_AUXFLTR;
633 			lazy = flags = 0;
634 			continue;
635 		case DT_SUNW_AUXILIARY:
636 			dip->di_flags |= (FLG_DI_AUXFLTR | FLG_DI_SYMFLTR);
637 			lazy = flags = 0;
638 			continue;
639 		case DT_FILTER:
640 			dip->di_flags |= FLG_DI_STDFLTR;
641 			lazy = flags = 0;
642 			continue;
643 		case DT_SUNW_FILTER:
644 			dip->di_flags |= (FLG_DI_STDFLTR | FLG_DI_SYMFLTR);
645 			lazy = flags = 0;
646 			continue;
647 		default:
648 			lazy = flags = 0;
649 			continue;
650 		}
651 
652 		DBG_CALL(Dbg_file_needed(clmp, name));
653 		if (lml->lm_flags & LML_FLG_TRC_ENABLE)
654 			dip->di_flags |= FLG_DI_PROCESSD;
655 
656 		/*
657 		 * Establish the objects name, load it and establish a binding
658 		 * with the caller.
659 		 */
660 		if (((pnp = elf_fix_name(name, clmp, PN_SER_NEEDED)) == 0) ||
661 		    ((nlmp = load_one(lml, lmco, pnp, clmp, MODE(clmp),
662 		    flags, 0)) == 0) || (bind_one(clmp, nlmp, BND_NEEDED) == 0))
663 			nlmp = 0;
664 
665 		/*
666 		 * Clean up any infrastructure, including the removal of the
667 		 * error suppression state, if it had been previously set in
668 		 * this routine.
669 		 */
670 		if (pnp)
671 			remove_pnode(pnp);
672 		if (silent)
673 			rtld_flags &= ~RT_FL_SILENCERR;
674 		lazy = flags = 0;
675 		if ((dip->di_info = (void *)nlmp) == 0) {
676 			/*
677 			 * If the object could not be mapped, continue if error
678 			 * suppression is established or we're here with ldd(1).
679 			 */
680 			if ((MODE(clmp) & RTLD_CONFGEN) || (lmflags &
681 			    (LML_FLG_LOADAVAIL | LML_FLG_TRC_ENABLE)))
682 				continue;
683 			else
684 				return (0);
685 		}
686 	}
687 
688 	if (LAZY(clmp))
689 		lml->lm_lazy++;
690 
691 	return (1);
692 }
693 
694 static int
695 elf_map_check(Lm_list *lml, const char *name, caddr_t vaddr, Off size)
696 {
697 	prmap_t		*maps, *_maps;
698 	int		pfd, num, _num;
699 	caddr_t		eaddr = vaddr + size;
700 	int		err;
701 
702 	/*
703 	 * If memory reservations have been established for alternative objects
704 	 * determine if this object falls within the reservation, if it does no
705 	 * further checking is required.
706 	 */
707 	if (rtld_flags & RT_FL_MEMRESV) {
708 		Rtc_head	*head = (Rtc_head *)config->c_bgn;
709 
710 		if ((vaddr >= (caddr_t)(uintptr_t)head->ch_resbgn) &&
711 		    (eaddr <= (caddr_t)(uintptr_t)head->ch_resend))
712 			return (0);
713 	}
714 
715 	/*
716 	 * Determine the mappings presently in use by this process.
717 	 */
718 	if ((pfd = pr_open(lml)) == FD_UNAVAIL)
719 		return (1);
720 
721 	if (ioctl(pfd, PIOCNMAP, (void *)&num) == -1) {
722 		err = errno;
723 		eprintf(lml, ERR_FATAL, MSG_INTL(MSG_SYS_PROC), name,
724 		    strerror(err));
725 		return (1);
726 	}
727 
728 	if ((maps = malloc((num + 1) * sizeof (prmap_t))) == 0)
729 		return (1);
730 
731 	if (ioctl(pfd, PIOCMAP, (void *)maps) == -1) {
732 		err = errno;
733 		eprintf(lml, ERR_FATAL, MSG_INTL(MSG_SYS_PROC), name,
734 		    strerror(err));
735 		free(maps);
736 		return (1);
737 	}
738 
739 	/*
740 	 * Determine if the supplied address clashes with any of the present
741 	 * process mappings.
742 	 */
743 	for (_num = 0, _maps = maps; _num < num; _num++, _maps++) {
744 		caddr_t		_eaddr = _maps->pr_vaddr + _maps->pr_size;
745 		Rt_map		*lmp;
746 		const char	*str;
747 
748 		if ((eaddr < _maps->pr_vaddr) || (vaddr >= _eaddr))
749 			continue;
750 
751 		/*
752 		 * We have a memory clash.  See if one of the known dynamic
753 		 * dependency mappings represents this space so as to provide
754 		 * the user a more meaningful message.
755 		 */
756 		if ((lmp = _caller(vaddr, 0)) != 0)
757 			str = NAME(lmp);
758 		else
759 			str = MSG_INTL(MSG_STR_UNKNOWN);
760 
761 		eprintf(lml, ERR_FATAL, MSG_INTL(MSG_GEN_MAPINUSE), name,
762 		    EC_NATPTR(vaddr), EC_OFF(size), str);
763 		return (1);
764 	}
765 	free(maps);
766 	return (0);
767 }
768 
769 /*
770  * Obtain a memory reservation.  On newer systems, both MAP_ANON and MAP_ALIGN
771  * are used to obtained an aligned reservation from anonymous memory.  If
772  * MAP_ANON isn't available, then MAP_ALIGN isn't either, so obtain a standard
773  * reservation using the file as backing.
774  */
775 static Am_ret
776 elf_map_reserve(Lm_list *lml, const char *name, caddr_t *maddr, Off msize,
777     int mperm, int fd, Xword align)
778 {
779 	Am_ret	amret;
780 	int	mflag = MAP_PRIVATE | MAP_NORESERVE;
781 
782 #if defined(MAP_ALIGN)
783 	if ((rtld_flags2 & RT_FL2_NOMALIGN) == 0) {
784 		mflag |= MAP_ALIGN;
785 		*maddr = (caddr_t)align;
786 	}
787 #endif
788 	if ((amret = anon_map(lml, maddr, msize, PROT_NONE, mflag)) == AM_ERROR)
789 		return (amret);
790 
791 	if (amret == AM_OK)
792 		return (AM_OK);
793 
794 	/*
795 	 * If an anonymous memory request failed (which should only be the
796 	 * case if it is unsupported on the system we're running on), establish
797 	 * the initial mapping directly from the file.
798 	 */
799 	*maddr = 0;
800 	if ((*maddr = mmap(*maddr, msize, mperm, MAP_PRIVATE,
801 	    fd, 0)) == MAP_FAILED) {
802 		int	err = errno;
803 		eprintf(lml, ERR_FATAL, MSG_INTL(MSG_SYS_MMAP), name,
804 		    strerror(err));
805 		return (AM_ERROR);
806 	}
807 	return (AM_NOSUP);
808 }
809 
810 static void *
811 elf_map_textdata(caddr_t addr, Off flen, int mperm, int phdr_mperm, int mflag,
812     int fd, Off foff)
813 {
814 #if	defined(MAP_TEXT) && defined(MAP_INITDATA)
815 	static int	notd = 0;
816 
817 	/*
818 	 * If MAP_TEXT and MAP_INITDATA are available, select the appropriate
819 	 * flag.
820 	 */
821 	if (notd == 0) {
822 		if ((phdr_mperm & (PROT_WRITE | PROT_EXEC)) == PROT_EXEC)
823 			mflag |= MAP_TEXT;
824 		else
825 			mflag |= MAP_INITDATA;
826 	}
827 #endif
828 	if (mmap((caddr_t)addr, flen, mperm, mflag, fd, foff) != MAP_FAILED)
829 		return (0);
830 
831 #if	defined(MAP_TEXT) && defined(MAP_INITDATA)
832 	if ((notd == 0) && (errno == EINVAL)) {
833 		/*
834 		 * MAP_TEXT and MAP_INITDATA may not be supported on this
835 		 * platform, try again without.
836 		 */
837 		notd = 1;
838 		mflag &= ~(MAP_TEXT | MAP_INITDATA);
839 
840 		return (mmap((caddr_t)addr, flen, mperm, mflag, fd, foff));
841 	}
842 #endif
843 	return (MAP_FAILED);
844 }
845 
846 /*
847  * Map in a file.
848  */
849 static caddr_t
850 elf_map_it(
851 	Lm_list		*lml,		/* link-map list */
852 	const char	*name,		/* actual name stored for pathname */
853 	Off		fsize,		/* total mapping claim of the file */
854 	Ehdr		*ehdr,		/* ELF header of file */
855 	Phdr		*fphdr,		/* first loadable Phdr */
856 	Phdr		*lphdr,		/* last loadable Phdr */
857 	Phdr		**rrphdr,	/* return first Phdr in reservation */
858 	caddr_t		*rraddr,	/* return start of reservation */
859 	Off		*rrsize,	/* return total size of reservation */
860 	int		fixed,		/* image is resolved to a fixed addr */
861 	int		fd,		/* images file descriptor */
862 	Xword		align,		/* image segments maximum alignment */
863 	Mmap		*mmaps,		/* mmap information array and */
864 	uint_t		*mmapcnt)	/* 	mapping count */
865 {
866 	caddr_t		raddr;		/* reservation address */
867 	Off		rsize;		/* reservation size */
868 	Phdr		*phdr;		/* working program header poiner */
869 	caddr_t		maddr;		/* working mmap address */
870 	caddr_t		faddr;		/* working file address */
871 	size_t		padsize;	/* object padding requirement */
872 	size_t		padpsize = 0;	/* padding size rounded to next page */
873 	size_t		padmsize = 0;	/* padding size rounded for alignment */
874 	int		skipfseg;	/* skip mapping first segment */
875 	int		mperm;		/* segment permissions */
876 	Am_ret		amret = AM_NOSUP;
877 
878 	/*
879 	 * If padding is required extend both the front and rear of the image.
880 	 * To insure the image itself is mapped at the correct alignment the
881 	 * initial padding is rounded up to the nearest page.  Once the image is
882 	 * mapped the excess can be pruned to the nearest page required for the
883 	 * actual padding itself.
884 	 */
885 	if ((padsize = r_debug.rtd_objpad) != 0) {
886 		padpsize = M_PROUND(padsize);
887 		if (fixed)
888 			padmsize = padpsize;
889 		else
890 			padmsize = S_ROUND(padsize, align);
891 	}
892 
893 	/*
894 	 * Determine the initial permissions used to map in the first segment.
895 	 * If this segments memsz is greater that its filesz then the difference
896 	 * must be zeroed.  Make sure this segment is writable.
897 	 */
898 	mperm = 0;
899 	if (fphdr->p_flags & PF_R)
900 		mperm |= PROT_READ;
901 	if (fphdr->p_flags & PF_X)
902 		mperm |= PROT_EXEC;
903 	if ((fphdr->p_flags & PF_W) || (fphdr->p_memsz > fphdr->p_filesz))
904 		mperm |= PROT_WRITE;
905 
906 	/*
907 	 * Determine whether or not to let system reserve address space based on
908 	 * whether this is a dynamic executable (addresses in object are fixed)
909 	 * or a shared object (addresses in object are relative to the objects'
910 	 * base).
911 	 */
912 	if (fixed) {
913 		/*
914 		 * Determine the reservation address and size, and insure that
915 		 * this reservation isn't already in use.
916 		 */
917 		faddr = maddr = (caddr_t)M_PTRUNC((ulong_t)fphdr->p_vaddr);
918 		raddr = maddr - padpsize;
919 		rsize = fsize + padpsize + padsize;
920 
921 		if (lml_main.lm_head) {
922 			if (elf_map_check(lml, name, raddr, rsize) != 0)
923 				return (0);
924 		}
925 
926 		/*
927 		 * As this is a fixed image, all segments must be individually
928 		 * mapped.
929 		 */
930 		skipfseg = 0;
931 
932 	} else {
933 		size_t	esize;
934 
935 		/*
936 		 * If this isn't a fixed image, reserve enough address space for
937 		 * the entire image to be mapped.  The amount of reservation is
938 		 * the range between the beginning of the first, and end of the
939 		 * last loadable segment, together with any padding, plus the
940 		 * alignment of the first segment.
941 		 *
942 		 * The optimal reservation is made as a no-reserve mapping from
943 		 * anonymous memory.  Each segment is then mapped into this
944 		 * reservation.  If the anonymous mapping capability isn't
945 		 * available, the reservation is obtained from the file itself.
946 		 * In this case the first segment of the image is mapped as part
947 		 * of the reservation, thus only the following segments need to
948 		 * be remapped.
949 		 */
950 		rsize = fsize + padmsize + padsize;
951 		if ((amret = elf_map_reserve(lml, name, &raddr, rsize, mperm,
952 		    fd, align)) == AM_ERROR)
953 			return (0);
954 		maddr = raddr + padmsize;
955 		faddr = (caddr_t)S_ROUND((Off)maddr, align);
956 
957 		/*
958 		 * If this reservation has been obtained from anonymous memory,
959 		 * then all segments must be individually mapped.  Otherwise,
960 		 * the first segment heads the reservation.
961 		 */
962 		if (amret == AM_OK)
963 			skipfseg = 0;
964 		else
965 			skipfseg = 1;
966 
967 		/*
968 		 * For backward compatibility (where MAP_ALIGN isn't available),
969 		 * insure the alignment of the reservation is adequate for this
970 		 * object, and if not remap the object to obtain the correct
971 		 * alignment.
972 		 */
973 		if (faddr != maddr) {
974 			(void) munmap(raddr, rsize);
975 
976 			rsize += align;
977 			if ((amret = elf_map_reserve(lml, name, &raddr, rsize,
978 			    mperm, fd, align)) == AM_ERROR)
979 				return (0);
980 
981 			maddr = faddr = (caddr_t)S_ROUND((Off)(raddr +
982 			    padpsize), align);
983 
984 			esize = maddr - raddr + padpsize;
985 
986 			/*
987 			 * As ths image has been realigned, the first segment
988 			 * of the file needs to be remapped to its correct
989 			 * location.
990 			 */
991 			skipfseg = 0;
992 		} else
993 			esize = padmsize - padpsize;
994 
995 		/*
996 		 * If this reservation included padding, remove any excess for
997 		 * the start of the image (the padding was adjusted to insure
998 		 * the image was aligned appropriately).
999 		 */
1000 		if (esize) {
1001 			(void) munmap(raddr, esize);
1002 			raddr += esize;
1003 			rsize -= esize;
1004 		}
1005 	}
1006 
1007 	/*
1008 	 * At this point we know the initial location of the image, and its
1009 	 * size.  Pass these back to the caller for inclusion in the link-map
1010 	 * that will eventually be created.
1011 	 */
1012 	*rraddr = raddr;
1013 	*rrsize = rsize;
1014 
1015 	/*
1016 	 * The first loadable segment is now pointed to by maddr.  This segment
1017 	 * will eventually contain the elf header and program headers, so reset
1018 	 * the program header.  Pass this  back to the caller for inclusion in
1019 	 * the link-map so it can be used for later unmapping operations.
1020 	 */
1021 	/* LINTED */
1022 	*rrphdr = (Phdr *)((char *)maddr + ehdr->e_phoff);
1023 
1024 	/*
1025 	 * If padding is required at the front of the image, obtain that now.
1026 	 * Note, if we've already obtained a reservation from anonymous memory
1027 	 * then this reservation will already include suitable padding.
1028 	 * Otherwise this reservation is backed by the file, or in the case of
1029 	 * a fixed image, doesn't yet exist.  Map the padding so that it is
1030 	 * suitably protected (PROT_NONE), and insure the first segment of the
1031 	 * file is mapped to its correct location.
1032 	 */
1033 	if (padsize) {
1034 		if (amret == AM_NOSUP) {
1035 			if (dz_map(lml, raddr, padpsize, PROT_NONE,
1036 			    (MAP_PRIVATE | MAP_FIXED | MAP_NORESERVE)) ==
1037 			    MAP_FAILED)
1038 				return (0);
1039 
1040 			skipfseg = 0;
1041 		}
1042 		rsize -= padpsize;
1043 	}
1044 
1045 	/*
1046 	 * Map individual segments.  For a fixed image, these will each be
1047 	 * unique mappings.  For a reservation these will fill in the
1048 	 * reservation.
1049 	 */
1050 	for (phdr = fphdr; phdr <= lphdr;
1051 	    phdr = (Phdr *)((Off)phdr + ehdr->e_phentsize)) {
1052 		caddr_t	addr;
1053 		Off	mlen, flen;
1054 		size_t	size;
1055 
1056 		/*
1057 		 * Skip non-loadable segments or segments that don't occupy
1058 		 * any memory.
1059 		 */
1060 		if (((phdr->p_type != PT_LOAD) &&
1061 		    (phdr->p_type != PT_SUNWBSS)) || (phdr->p_memsz == 0))
1062 			continue;
1063 
1064 		/*
1065 		 * Establish this segments address relative to our base.
1066 		 */
1067 		addr = (caddr_t)M_PTRUNC((ulong_t)(phdr->p_vaddr +
1068 		    (fixed ? 0 : faddr)));
1069 
1070 		/*
1071 		 * Determine the mapping protection from the segment attributes.
1072 		 * Also determine the etext address from the last loadable
1073 		 * segment which has permissions but no write access.
1074 		 */
1075 		mperm = 0;
1076 		if (phdr->p_flags) {
1077 			if (phdr->p_flags & PF_R)
1078 				mperm |= PROT_READ;
1079 			if (phdr->p_flags & PF_X)
1080 				mperm |= PROT_EXEC;
1081 			if (phdr->p_flags & PF_W)
1082 				mperm |= PROT_WRITE;
1083 			else
1084 				fmap->fm_etext = phdr->p_vaddr + phdr->p_memsz +
1085 				    (ulong_t)(fixed ? 0 : faddr);
1086 		}
1087 
1088 		/*
1089 		 * Determine the type of mapping required.
1090 		 */
1091 		if (phdr->p_type == PT_SUNWBSS) {
1092 			/*
1093 			 * Potentially, we can defer the loading of any SUNWBSS
1094 			 * segment, depending on whether the symbols it provides
1095 			 * have been bound to.  In this manner, large segments
1096 			 * that are interposed upon between shared libraries
1097 			 * may not require mapping.  Note, that the mapping
1098 			 * information is recorded in our mapping descriptor at
1099 			 * this time.
1100 			 */
1101 			mlen = phdr->p_memsz;
1102 			flen = 0;
1103 
1104 		} else if ((phdr->p_filesz == 0) && (phdr->p_flags == 0)) {
1105 			/*
1106 			 * If this segment has no backing file and no flags
1107 			 * specified, then it defines a reservation.  At this
1108 			 * point all standard loadable segments will have been
1109 			 * processed.  The segment reservation is mapped
1110 			 * directly from /dev/null.
1111 			 */
1112 			if (nu_map(lml, (caddr_t)addr, phdr->p_memsz, PROT_NONE,
1113 			    MAP_FIXED | MAP_PRIVATE) == MAP_FAILED)
1114 				return (0);
1115 
1116 			mlen = phdr->p_memsz;
1117 			flen = 0;
1118 
1119 		} else if (phdr->p_filesz == 0) {
1120 			/*
1121 			 * If this segment has no backing file then it defines a
1122 			 * nobits segment and is mapped directly from /dev/zero.
1123 			 */
1124 			if (dz_map(lml, (caddr_t)addr, phdr->p_memsz, mperm,
1125 			    MAP_FIXED | MAP_PRIVATE) == MAP_FAILED)
1126 				return (0);
1127 
1128 			mlen = phdr->p_memsz;
1129 			flen = 0;
1130 
1131 		} else {
1132 			Off	foff;
1133 
1134 			/*
1135 			 * This mapping originates from the file.  Determine the
1136 			 * file offset to which the mapping will be directed
1137 			 * (must be aligned) and how much to map (might be more
1138 			 * than the file in the case of .bss).
1139 			 */
1140 			foff = M_PTRUNC((ulong_t)phdr->p_offset);
1141 			mlen = phdr->p_memsz + (phdr->p_offset - foff);
1142 			flen = phdr->p_filesz + (phdr->p_offset - foff);
1143 
1144 			/*
1145 			 * If this is a non-fixed, non-anonymous mapping, and no
1146 			 * padding is involved, then the first loadable segment
1147 			 * is already part of the initial reservation.  In this
1148 			 * case there is no need to remap this segment.
1149 			 */
1150 			if ((skipfseg == 0) || (phdr != fphdr)) {
1151 				int phdr_mperm = mperm;
1152 				/*
1153 				 * If this segments memsz is greater that its
1154 				 * filesz then the difference must be zeroed.
1155 				 * Make sure this segment is writable.
1156 				 */
1157 				if (phdr->p_memsz > phdr->p_filesz)
1158 					mperm |= PROT_WRITE;
1159 
1160 				if (elf_map_textdata((caddr_t)addr, flen,
1161 				    mperm, phdr_mperm,
1162 				    (MAP_FIXED | MAP_PRIVATE), fd, foff) ==
1163 				    MAP_FAILED) {
1164 					int	err = errno;
1165 					eprintf(lml, ERR_FATAL,
1166 					    MSG_INTL(MSG_SYS_MMAP), name,
1167 					    strerror(err));
1168 					return (0);
1169 				}
1170 			}
1171 
1172 			/*
1173 			 * If the memory occupancy of the segment overflows the
1174 			 * definition in the file, we need to "zero out" the end
1175 			 * of the mapping we've established, and if necessary,
1176 			 * map some more space from /dev/zero.  Note, zero'ed
1177 			 * memory must end on a double word boundary to satisfy
1178 			 * zero().
1179 			 */
1180 			if (phdr->p_memsz > phdr->p_filesz) {
1181 				caddr_t	zaddr;
1182 				size_t	zlen, zplen;
1183 				Off	fend;
1184 
1185 				foff = (Off)(phdr->p_vaddr + phdr->p_filesz +
1186 				    (fixed ? 0 : faddr));
1187 				zaddr = (caddr_t)M_PROUND(foff);
1188 				zplen = (size_t)(zaddr - foff);
1189 
1190 				fend = (Off)S_DROUND((size_t)(phdr->p_vaddr +
1191 				    phdr->p_memsz + (fixed ? 0 : faddr)));
1192 				zlen = (size_t)(fend - foff);
1193 
1194 				/*
1195 				 * Determine whether the number of bytes that
1196 				 * must be zero'ed overflow to the next page.
1197 				 * If not, simply clear the exact bytes
1198 				 * (filesz to memsz) from this page.  Otherwise,
1199 				 * clear the remaining bytes of this page, and
1200 				 * map an following pages from /dev/zero.
1201 				 */
1202 				if (zlen < zplen)
1203 					zero((caddr_t)foff, (long)zlen);
1204 				else {
1205 					zero((caddr_t)foff, (long)zplen);
1206 
1207 					if ((zlen = (fend - (Off)zaddr)) > 0) {
1208 						if (dz_map(lml, zaddr, zlen,
1209 						    mperm,
1210 						    MAP_FIXED | MAP_PRIVATE) ==
1211 						    MAP_FAILED)
1212 							return (0);
1213 					}
1214 				}
1215 			}
1216 		}
1217 
1218 		/*
1219 		 * Unmap anything from the last mapping address to this one and
1220 		 * update the mapping claim pointer.
1221 		 */
1222 		if ((fixed == 0) && ((size = addr - maddr) != 0)) {
1223 			(void) munmap(maddr, size);
1224 			rsize -= size;
1225 		}
1226 
1227 		/*
1228 		 * Retain this segments mapping information.
1229 		 */
1230 		mmaps[*mmapcnt].m_vaddr = addr;
1231 		mmaps[*mmapcnt].m_msize = mlen;
1232 		mmaps[*mmapcnt].m_fsize = flen;
1233 		mmaps[*mmapcnt].m_perm = mperm;
1234 		(*mmapcnt)++;
1235 
1236 		maddr = addr + M_PROUND(mlen);
1237 		rsize -= M_PROUND(mlen);
1238 	}
1239 
1240 	/*
1241 	 * If padding is required at the end of the image, obtain that now.
1242 	 * Note, if we've already obtained a reservation from anonymous memory
1243 	 * then this reservation will already include suitable padding.
1244 	 */
1245 	if (padsize) {
1246 		if (amret == AM_NOSUP) {
1247 			/*
1248 			 * maddr is currently page aligned from the last segment
1249 			 * mapping.
1250 			 */
1251 			if (dz_map(lml, maddr, padsize, PROT_NONE,
1252 			    (MAP_PRIVATE | MAP_FIXED | MAP_NORESERVE)) ==
1253 			    MAP_FAILED)
1254 				return (0);
1255 		}
1256 		maddr += padsize;
1257 		rsize -= padsize;
1258 	}
1259 
1260 	/*
1261 	 * Unmap any final reservation.
1262 	 */
1263 	if ((fixed == 0) && (rsize != 0))
1264 		(void) munmap(maddr, rsize);
1265 
1266 	return (faddr);
1267 }
1268 
1269 /*
1270  * A null symbol interpretor.  Used if a filter has no associated filtees.
1271  */
1272 /* ARGSUSED0 */
1273 static Sym *
1274 elf_null_find_sym(Slookup *slp, Rt_map **dlmp, uint_t *binfo)
1275 {
1276 	return ((Sym *)0);
1277 }
1278 
1279 /*
1280  * Disable filtee use.
1281  */
1282 static void
1283 elf_disable_filtee(Rt_map *lmp, Dyninfo *dip)
1284 {
1285 	dip->di_info = 0;
1286 
1287 	if ((dip->di_flags & FLG_DI_SYMFLTR) == 0) {
1288 		/*
1289 		 * If this is an object filter, free the filtee's duplication.
1290 		 */
1291 		if (OBJFLTRNDX(lmp) != FLTR_DISABLED) {
1292 			free(REFNAME(lmp));
1293 			REFNAME(lmp) = (char *)0;
1294 			OBJFLTRNDX(lmp) = FLTR_DISABLED;
1295 
1296 			/*
1297 			 * Indicate that this filtee is no longer available.
1298 			 */
1299 			if (dip->di_flags & FLG_DI_STDFLTR)
1300 				SYMINTP(lmp) = elf_null_find_sym;
1301 
1302 		}
1303 	} else if (dip->di_flags & FLG_DI_STDFLTR) {
1304 		/*
1305 		 * Indicate that this standard filtee is no longer available.
1306 		 */
1307 		if (SYMSFLTRCNT(lmp))
1308 			SYMSFLTRCNT(lmp)--;
1309 	} else {
1310 		/*
1311 		 * Indicate that this auxiliary filtee is no longer available.
1312 		 */
1313 		if (SYMAFLTRCNT(lmp))
1314 			SYMAFLTRCNT(lmp)--;
1315 	}
1316 	dip->di_flags &= ~MSK_DI_FILTER;
1317 }
1318 
1319 /*
1320  * Find symbol interpreter - filters.
1321  * This function is called when the symbols from a shared object should
1322  * be resolved from the shared objects filtees instead of from within itself.
1323  *
1324  * A symbol name of 0 is used to trigger filtee loading.
1325  */
1326 static Sym *
1327 _elf_lookup_filtee(Slookup *slp, Rt_map **dlmp, uint_t *binfo, uint_t ndx)
1328 {
1329 	const char	*name = slp->sl_name, *filtees;
1330 	Rt_map		*clmp = slp->sl_cmap;
1331 	Rt_map		*ilmp = slp->sl_imap;
1332 	Pnode		*pnp, **pnpp;
1333 	int		any;
1334 	Dyninfo		*dip = &DYNINFO(ilmp)[ndx];
1335 	Lm_list		*lml = LIST(ilmp);
1336 
1337 	/*
1338 	 * Indicate that the filter has been used.  If a binding already exists
1339 	 * to the caller, indicate that this object is referenced.  This insures
1340 	 * we don't generate false unreferenced diagnostics from ldd -u/U or
1341 	 * debugging.  Don't create a binding regardless, as this filter may
1342 	 * have been dlopen()'ed.
1343 	 */
1344 	if (name && (ilmp != clmp)) {
1345 		Word	tracing = (LIST(clmp)->lm_flags &
1346 		    (LML_FLG_TRC_UNREF | LML_FLG_TRC_UNUSED));
1347 
1348 		if (tracing || DBG_ENABLED) {
1349 			Bnd_desc **	bdpp;
1350 			Aliste		off;
1351 
1352 			FLAGS1(ilmp) |= FL1_RT_USED;
1353 
1354 			if ((tracing & LML_FLG_TRC_UNREF) || DBG_ENABLED) {
1355 				for (ALIST_TRAVERSE(CALLERS(ilmp), off, bdpp)) {
1356 					Bnd_desc *	bdp = *bdpp;
1357 
1358 					if (bdp->b_caller == clmp) {
1359 						bdp->b_flags |= BND_REFER;
1360 						break;
1361 					}
1362 				}
1363 			}
1364 		}
1365 	}
1366 
1367 	/*
1368 	 * If this is the first call to process this filter, establish the
1369 	 * filtee list.  If a configuration file exists, determine if any
1370 	 * filtee associations for this filter, and its filtee reference, are
1371 	 * defined.  Otherwise, process the filtee reference.  Any token
1372 	 * expansion is also completed at this point (i.e., $PLATFORM).
1373 	 */
1374 	filtees = (char *)STRTAB(ilmp) + DYN(ilmp)[ndx].d_un.d_val;
1375 	if (dip->di_info == 0) {
1376 		if (rtld_flags2 & RT_FL2_FLTCFG)
1377 			dip->di_info = elf_config_flt(lml, PATHNAME(ilmp),
1378 			    filtees);
1379 
1380 		if (dip->di_info == 0) {
1381 			DBG_CALL(Dbg_file_filter(lml, NAME(ilmp), filtees, 0));
1382 			if ((lml->lm_flags &
1383 			    (LML_FLG_TRC_VERBOSE | LML_FLG_TRC_SEARCH)) &&
1384 			    ((FLAGS1(ilmp) & FL1_RT_LDDSTUB) == 0))
1385 				(void) printf(MSG_INTL(MSG_LDD_FIL_FILTER),
1386 				    NAME(ilmp), filtees);
1387 
1388 			if ((dip->di_info = (void *)expand_paths(ilmp,
1389 			    filtees, PN_SER_FILTEE, 0)) == 0) {
1390 				elf_disable_filtee(ilmp, dip);
1391 				return ((Sym *)0);
1392 			}
1393 		}
1394 	}
1395 
1396 	/*
1397 	 * Traverse the filtee list, dlopen()'ing any objects specified and
1398 	 * using their group handle to lookup the symbol.
1399 	 */
1400 	for (any = 0, pnpp = (Pnode **)&(dip->di_info), pnp = *pnpp; pnp;
1401 	    pnpp = &pnp->p_next, pnp = *pnpp) {
1402 		int	mode;
1403 		Grp_hdl	*ghp;
1404 		Rt_map	*nlmp = 0;
1405 
1406 		if (pnp->p_len == 0)
1407 			continue;
1408 
1409 		/*
1410 		 * Establish the mode of the filtee from the filter.  As filtees
1411 		 * are loaded via a dlopen(), make sure that RTLD_GROUP is set
1412 		 * and the filtees aren't global.  It would be nice to have
1413 		 * RTLD_FIRST used here also, but as filters got out long before
1414 		 * RTLD_FIRST was introduced it's a little too late now.
1415 		 */
1416 		mode = MODE(ilmp) | RTLD_GROUP;
1417 		mode &= ~RTLD_GLOBAL;
1418 
1419 		/*
1420 		 * Insure that any auxiliary filter can locate symbols from its
1421 		 * caller.
1422 		 */
1423 		if (dip->di_flags & FLG_DI_AUXFLTR)
1424 			mode |= RTLD_PARENT;
1425 
1426 		/*
1427 		 * Process any hardware capability directory.  Establish a new
1428 		 * link-map control list from which to analyze any newly added
1429 		 * objects.
1430 		 */
1431 		if ((pnp->p_info == 0) && (pnp->p_orig & PN_TKN_HWCAP)) {
1432 			Lm_cntl	*lmc;
1433 			Aliste	lmco;
1434 
1435 			if (FLAGS(lml->lm_head) & FLG_RT_RELOCED) {
1436 				if ((lmc = alist_append(&(lml->lm_lists), 0,
1437 				    sizeof (Lm_cntl), AL_CNT_LMLISTS)) == 0)
1438 					return ((Sym *)0);
1439 				lmco = (Aliste)((char *)lmc -
1440 				    (char *)lml->lm_lists);
1441 			} else {
1442 				lmc = 0;
1443 				lmco = ALO_DATA;
1444 			}
1445 
1446 			pnp = hwcap_filtees(pnpp, lmco, lmc, dip, ilmp, filtees,
1447 			    mode, (FLG_RT_HANDLE | FLG_RT_HWCAP));
1448 
1449 			/*
1450 			 * Now that any hardware capability objects have been
1451 			 * processed, remove any link-map control list.
1452 			 */
1453 			if (lmc)
1454 				remove_cntl(lml, lmco);
1455 		}
1456 
1457 		if (pnp->p_len == 0)
1458 			continue;
1459 
1460 		/*
1461 		 * Process an individual filtee.
1462 		 */
1463 		if (pnp->p_info == 0) {
1464 			const char	*filtee = pnp->p_name;
1465 			int		audit = 0;
1466 
1467 			DBG_CALL(Dbg_file_filtee(lml, NAME(ilmp), filtee, 0));
1468 
1469 			ghp = 0;
1470 
1471 			/*
1472 			 * Determine if the reference link map is already
1473 			 * loaded.  As an optimization compare the filtee with
1474 			 * our interpretor.  The most common filter is
1475 			 * libdl.so.1, which is a filter on ld.so.1.
1476 			 */
1477 #if	defined(_ELF64)
1478 			if (strcmp(filtee, MSG_ORIG(MSG_PTH_RTLD_64)) == 0) {
1479 #else
1480 			if (strcmp(filtee, MSG_ORIG(MSG_PTH_RTLD)) == 0) {
1481 #endif
1482 				/*
1483 				 * Create an association between ld.so.1 and
1484 				 * the filter.
1485 				 */
1486 				nlmp = lml_rtld.lm_head;
1487 				if ((ghp = hdl_create(&lml_rtld, nlmp, ilmp,
1488 				    (GPH_LDSO | GPH_FIRST | GPH_FILTEE))) == 0)
1489 					nlmp = 0;
1490 
1491 				/*
1492 				 * Establish the filter handle to prevent any
1493 				 * recursion.
1494 				 */
1495 				if (nlmp && ghp)
1496 					pnp->p_info = (void *)ghp;
1497 
1498 				/*
1499 				 * Audit the filter/filtee established.  Ignore
1500 				 * any return from the auditor, as we can't
1501 				 * allow ignore filtering to ld.so.1, otherwise
1502 				 * nothing is going to work.
1503 				 */
1504 				if (nlmp && ((lml->lm_tflags | FLAGS1(ilmp)) &
1505 				    LML_TFLG_AUD_OBJFILTER))
1506 					(void) audit_objfilter(ilmp, filtees,
1507 					    nlmp, 0);
1508 
1509 			} else {
1510 				Rej_desc	rej = { 0 };
1511 				Lm_cntl		*lmc;
1512 				Aliste		lmco;
1513 
1514 				/*
1515 				 * Establish a new link-map control list from
1516 				 * which to analyze any newly added objects.
1517 				 */
1518 				if (FLAGS(lml->lm_head) & FLG_RT_RELOCED) {
1519 					if ((lmc =
1520 					    alist_append(&(lml->lm_lists), 0,
1521 					    sizeof (Lm_cntl),
1522 					    AL_CNT_LMLISTS)) == 0)
1523 						return ((Sym *)0);
1524 					lmco = (Aliste)((char *)lmc -
1525 					    (char *)lml->lm_lists);
1526 				} else {
1527 					lmc = 0;
1528 					lmco = ALO_DATA;
1529 				}
1530 
1531 				/*
1532 				 * Load the filtee.
1533 				 */
1534 				if ((nlmp = load_path(lml, lmco, filtee, ilmp,
1535 				    mode, FLG_RT_HANDLE, &ghp, 0, &rej)) == 0) {
1536 					file_notfound(LIST(ilmp), filtee, ilmp,
1537 					    FLG_RT_HANDLE, &rej);
1538 					remove_rej(&rej);
1539 				}
1540 
1541 				/*
1542 				 * Establish the filter handle to prevent any
1543 				 * recursion.
1544 				 */
1545 				if (nlmp && ghp) {
1546 					ghp->gh_flags |= GPH_FILTEE;
1547 					pnp->p_info = (void *)ghp;
1548 				}
1549 
1550 				/*
1551 				 * Audit the filter/filtee established.  A
1552 				 * return of 0 indicates the auditor wishes to
1553 				 * ignore this filtee.
1554 				 */
1555 				if (nlmp && ((lml->lm_tflags | FLAGS1(ilmp)) &
1556 				    LML_TFLG_AUD_OBJFILTER)) {
1557 					if (audit_objfilter(ilmp, filtees,
1558 					    nlmp, 0) == 0) {
1559 						audit = 1;
1560 						nlmp = 0;
1561 					}
1562 				}
1563 
1564 				/*
1565 				 * Finish processing the objects associated with
1566 				 * this request.  Create an association between
1567 				 * this object and the originating filter to
1568 				 * provide sufficient information to tear down
1569 				 * this filtee if necessary.
1570 				 */
1571 				if (nlmp && ghp &&
1572 				    ((analyze_lmc(lml, lmco, nlmp) == 0) ||
1573 				    (relocate_lmc(lml, lmco, ilmp, nlmp) == 0)))
1574 					nlmp = 0;
1575 
1576 				/*
1577 				 * If the filtee has been successfully
1578 				 * processed, then create an association
1579 				 * between the filter and filtee.  This
1580 				 * association provides sufficient information
1581 				 * to tear down the filter and filtee if
1582 				 * necessary.
1583 				 */
1584 				DBG_CALL(Dbg_file_hdl_title(DBG_DEP_ADD));
1585 				if (nlmp && ghp &&
1586 				    (hdl_add(ghp, ilmp, GPD_FILTER) == 0))
1587 					nlmp = 0;
1588 
1589 				/*
1590 				 * If this filtee loading has failed, and we've
1591 				 * created a new link-map control list to which
1592 				 * this request has added objects, then remove
1593 				 * all the objects that have been associated to
1594 				 * this request.
1595 				 */
1596 				if ((nlmp == 0) && lmc && lmc->lc_head)
1597 					remove_lmc(lml, clmp, lmc, lmco, name);
1598 
1599 				/*
1600 				 * Remove any link-map control list that was
1601 				 * created.
1602 				 */
1603 				if (lmc)
1604 					remove_cntl(lml, lmco);
1605 			}
1606 
1607 			/*
1608 			 * Generate a diagnostic if the filtee couldn't be
1609 			 * loaded, null out the pnode entry, and continue
1610 			 * the search.  Otherwise, retain this group handle
1611 			 * for future symbol searches.
1612 			 */
1613 			if (nlmp == 0) {
1614 				DBG_CALL(Dbg_file_filtee(lml, 0, filtee,
1615 				    audit));
1616 
1617 				pnp->p_info = 0;
1618 				pnp->p_len = 0;
1619 				continue;
1620 			}
1621 		}
1622 
1623 		ghp = (Grp_hdl *)pnp->p_info;
1624 
1625 		/*
1626 		 * If we're just here to trigger filtee loading skip the symbol
1627 		 * lookup so we'll continue looking for additional filtees.
1628 		 */
1629 		if (name) {
1630 			Grp_desc	*gdp;
1631 			Sym		*sym = 0;
1632 			Aliste		off;
1633 			Slookup		sl = *slp;
1634 
1635 			sl.sl_flags |= LKUP_FIRST;
1636 			any++;
1637 
1638 			/*
1639 			 * Look for the symbol in the handles dependencies.
1640 			 */
1641 			for (ALIST_TRAVERSE(ghp->gh_depends, off, gdp)) {
1642 				if ((gdp->gd_flags & GPD_AVAIL) == 0)
1643 					continue;
1644 
1645 				/*
1646 				 * If our parent is a dependency don't look at
1647 				 * it (otherwise we are in a recursive loop).
1648 				 * This situation can occur with auxiliary
1649 				 * filters if the filtee has a dependency on the
1650 				 * filter.  This dependency isn't necessary as
1651 				 * auxiliary filters are opened RTLD_PARENT, but
1652 				 * users may still unknowingly add an explicit
1653 				 * dependency to the parent.
1654 				 */
1655 				if ((sl.sl_imap = gdp->gd_depend) == ilmp)
1656 					continue;
1657 
1658 				if (((sym = SYMINTP(sl.sl_imap)(&sl, dlmp,
1659 				    binfo)) != 0) ||
1660 				    (ghp->gh_flags & GPH_FIRST))
1661 					break;
1662 			}
1663 
1664 			/*
1665 			 * If a symbol has been found, indicate the binding
1666 			 * and return the symbol.
1667 			 */
1668 			if (sym) {
1669 				*binfo |= DBG_BINFO_FILTEE;
1670 				return (sym);
1671 			}
1672 		}
1673 
1674 		/*
1675 		 * If this object is tagged to terminate filtee processing we're
1676 		 * done.
1677 		 */
1678 		if (FLAGS1(ghp->gh_ownlmp) & FL1_RT_ENDFILTE)
1679 			break;
1680 	}
1681 
1682 	/*
1683 	 * If we're just here to trigger filtee loading then we're done.
1684 	 */
1685 	if (name == 0)
1686 		return ((Sym *)0);
1687 
1688 	/*
1689 	 * If no filtees have been found for a filter, clean up any Pnode
1690 	 * structures and disable their search completely.  For auxiliary
1691 	 * filters we can reselect the symbol search function so that we never
1692 	 * enter this routine again for this object.  For standard filters we
1693 	 * use the null symbol routine.
1694 	 */
1695 	if (any == 0) {
1696 		remove_pnode((Pnode *)dip->di_info);
1697 		elf_disable_filtee(ilmp, dip);
1698 		return ((Sym *)0);
1699 	}
1700 
1701 	return ((Sym *)0);
1702 }
1703 
1704 /*
1705  * Focal point for disabling error messages for auxiliary filters.  As an
1706  * auxiliary filter allows for filtee use, but provides a fallback should a
1707  * filtee not exist (or fail to load), any errors generated as a consequence of
1708  * trying to load the filtees are typically suppressed.  Setting RT_FL_SILENCERR
1709  * suppresses errors generated by eprint(), but insures a debug diagnostic is
1710  * produced.  ldd(1) employs printf(), and here, the selection of whether to
1711  * print a diagnostic in regards to auxiliary filters is a little more complex.
1712  *
1713  *   .	The determination of whether to produce an ldd message, or a fatal
1714  *	error message is driven by LML_FLG_TRC_ENABLE.
1715  *   .	More detailed ldd messages may also be driven off of LML_FLG_TRC_WARN,
1716  *	(ldd -d/-r), LML_FLG_TRC_VERBOSE (ldd -v), LML_FLG_TRC_SEARCH (ldd -s),
1717  *	and LML_FLG_TRC_UNREF/LML_FLG_TRC_UNUSED (ldd -U/-u).
1718  *
1719  *   .	If the calling object is lddstub, then several classes of message are
1720  *	suppressed.  The user isn't trying to diagnose lddstub, this is simply
1721  *	a stub executable employed to preload a user specified library against.
1722  *
1723  *   .	If RT_FL_SILENCERR is in effect then any generic ldd() messages should
1724  *	be suppressed.  All detailed ldd messages should still be produced.
1725  */
1726 Sym *
1727 elf_lookup_filtee(Slookup *slp, Rt_map **dlmp, uint_t *binfo, uint_t ndx)
1728 {
1729 	Sym	*sym;
1730 	Dyninfo	*dip = &DYNINFO(slp->sl_imap)[ndx];
1731 	int	silent = 0;
1732 
1733 	/*
1734 	 * Make sure this entry is still acting as a filter.  We may have tried
1735 	 * to process this previously, and disabled it if the filtee couldn't
1736 	 * be processed.  However, other entries may provide different filtees
1737 	 * that are yet to be completed.
1738 	 */
1739 	if (dip->di_flags == 0)
1740 		return ((Sym *)0);
1741 
1742 	/*
1743 	 * Indicate whether an error message is required should this filtee not
1744 	 * be found, based on the type of filter.
1745 	 */
1746 	if ((dip->di_flags & FLG_DI_AUXFLTR) &&
1747 	    ((rtld_flags & (RT_FL_WARNFLTR | RT_FL_SILENCERR)) == 0)) {
1748 		rtld_flags |= RT_FL_SILENCERR;
1749 		silent = 1;
1750 	}
1751 
1752 	sym = _elf_lookup_filtee(slp, dlmp, binfo, ndx);
1753 
1754 	if (silent)
1755 		rtld_flags &= ~RT_FL_SILENCERR;
1756 
1757 	return (sym);
1758 }
1759 
1760 /*
1761  * Compute the elf hash value (as defined in the ELF access library).
1762  * The form of the hash table is:
1763  *
1764  *	|--------------|
1765  *	| # of buckets |
1766  *	|--------------|
1767  *	| # of chains  |
1768  *	|--------------|
1769  *	|   bucket[]   |
1770  *	|--------------|
1771  *	|   chain[]    |
1772  *	|--------------|
1773  */
1774 ulong_t
1775 elf_hash(const char *name)
1776 {
1777 	uint_t	hval = 0;
1778 
1779 	while (*name) {
1780 		uint_t	g;
1781 		hval = (hval << 4) + *name++;
1782 		if ((g = (hval & 0xf0000000)) != 0)
1783 			hval ^= g >> 24;
1784 		hval &= ~g;
1785 	}
1786 	return ((ulong_t)hval);
1787 }
1788 
1789 /*
1790  * If flag argument has LKUP_SPEC set, we treat undefined symbols of type
1791  * function specially in the executable - if they have a value, even though
1792  * undefined, we use that value.  This allows us to associate all references
1793  * to a function's address to a single place in the process: the plt entry
1794  * for that function in the executable.  Calls to lookup from plt binding
1795  * routines do NOT set LKUP_SPEC in the flag.
1796  */
1797 Sym *
1798 elf_find_sym(Slookup *slp, Rt_map **dlmp, uint_t *binfo)
1799 {
1800 	const char	*name = slp->sl_name;
1801 	Rt_map		*ilmp = slp->sl_imap;
1802 	ulong_t		hash = slp->sl_hash;
1803 	uint_t		ndx, htmp, buckets, *chainptr;
1804 	Sym		*sym, *symtabptr;
1805 	char		*strtabptr, *strtabname;
1806 	uint_t		flags1;
1807 	Syminfo		*sip;
1808 
1809 	/*
1810 	 * If we're only here to establish a symbols index, skip the diagnostic
1811 	 * used to trace a symbol search.
1812 	 */
1813 	if ((slp->sl_flags & LKUP_SYMNDX) == 0)
1814 		DBG_CALL(Dbg_syms_lookup(ilmp, name, MSG_ORIG(MSG_STR_ELF)));
1815 
1816 	if (HASH(ilmp) == 0)
1817 		return ((Sym *)0);
1818 
1819 	buckets = HASH(ilmp)[0];
1820 	/* LINTED */
1821 	htmp = (uint_t)hash % buckets;
1822 
1823 	/*
1824 	 * Get the first symbol on hash chain and initialize the string
1825 	 * and symbol table pointers.
1826 	 */
1827 	if ((ndx = HASH(ilmp)[htmp + 2]) == 0)
1828 		return ((Sym *)0);
1829 
1830 	chainptr = HASH(ilmp) + 2 + buckets;
1831 	strtabptr = STRTAB(ilmp);
1832 	symtabptr = SYMTAB(ilmp);
1833 
1834 	while (ndx) {
1835 		sym = symtabptr + ndx;
1836 		strtabname = strtabptr + sym->st_name;
1837 
1838 		/*
1839 		 * Compare the symbol found with the name required.  If the
1840 		 * names don't match continue with the next hash entry.
1841 		 */
1842 		if ((*strtabname++ != *name) || strcmp(strtabname, &name[1])) {
1843 			if ((ndx = chainptr[ndx]) != 0)
1844 				continue;
1845 			return ((Sym *)0);
1846 		}
1847 
1848 		/*
1849 		 * If we're only here to establish a symbols index, we're done.
1850 		 */
1851 		if (slp->sl_flags & LKUP_SYMNDX)
1852 			return (sym);
1853 
1854 		/*
1855 		 * If we find a match and the symbol is defined, return the
1856 		 * symbol pointer and the link map in which it was found.
1857 		 */
1858 		if (sym->st_shndx != SHN_UNDEF) {
1859 			*dlmp = ilmp;
1860 			*binfo |= DBG_BINFO_FOUND;
1861 			if ((FLAGS(ilmp) & FLG_RT_OBJINTPO) ||
1862 			    ((FLAGS(ilmp) & FLG_RT_SYMINTPO) &&
1863 			    is_sym_interposer(ilmp, sym)))
1864 				*binfo |= DBG_BINFO_INTERPOSE;
1865 			break;
1866 
1867 		/*
1868 		 * If we find a match and the symbol is undefined, the
1869 		 * symbol type is a function, and the value of the symbol
1870 		 * is non zero, then this is a special case.  This allows
1871 		 * the resolution of a function address to the plt[] entry.
1872 		 * See SPARC ABI, Dynamic Linking, Function Addresses for
1873 		 * more details.
1874 		 */
1875 		} else if ((slp->sl_flags & LKUP_SPEC) &&
1876 		    (FLAGS(ilmp) & FLG_RT_ISMAIN) && (sym->st_value != 0) &&
1877 		    (ELF_ST_TYPE(sym->st_info) == STT_FUNC)) {
1878 			*dlmp = ilmp;
1879 			*binfo |= (DBG_BINFO_FOUND | DBG_BINFO_PLTADDR);
1880 			if ((FLAGS(ilmp) & FLG_RT_OBJINTPO) ||
1881 			    ((FLAGS(ilmp) & FLG_RT_SYMINTPO) &&
1882 			    is_sym_interposer(ilmp, sym)))
1883 				*binfo |= DBG_BINFO_INTERPOSE;
1884 			return (sym);
1885 		}
1886 
1887 		/*
1888 		 * Undefined symbol.
1889 		 */
1890 		return ((Sym *)0);
1891 	}
1892 
1893 	/*
1894 	 * We've found a match.  Determine if the defining object contains
1895 	 * symbol binding information.
1896 	 */
1897 	if ((sip = SYMINFO(ilmp)) != 0)
1898 		sip += ndx;
1899 
1900 	/*
1901 	 * If this is a direct binding request, but the symbol definition has
1902 	 * disabled directly binding to it (presumably because the symbol
1903 	 * definition has been changed since the referring object was built),
1904 	 * indicate this failure so that the caller can fall back to a standard
1905 	 * symbol search.  Clear any debug binding information for cleanliness.
1906 	 */
1907 	if (sip && (slp->sl_flags & LKUP_DIRECT) &&
1908 	    (sip->si_flags & SYMINFO_FLG_NOEXTDIRECT)) {
1909 		*binfo |= BINFO_DIRECTDIS;
1910 		*binfo &= ~DBG_BINFO_MSK;
1911 		return ((Sym *)0);
1912 	}
1913 
1914 	/*
1915 	 * Determine whether this object is acting as a filter.
1916 	 */
1917 	if (((flags1 = FLAGS1(ilmp)) & MSK_RT_FILTER) == 0)
1918 		return (sym);
1919 
1920 	/*
1921 	 * Determine if this object offers per-symbol filtering, and if so,
1922 	 * whether this symbol references a filtee.
1923 	 */
1924 	if (sip && (flags1 & (FL1_RT_SYMSFLTR | FL1_RT_SYMAFLTR))) {
1925 		/*
1926 		 * If this is a standard filter reference, and no standard
1927 		 * filtees remain to be inspected, we're done.  If this is an
1928 		 * auxiliary filter reference, and no auxiliary filtees remain,
1929 		 * we'll fall through in case any object filtering is available.
1930 		 */
1931 		if ((sip->si_flags & SYMINFO_FLG_FILTER) &&
1932 		    (SYMSFLTRCNT(ilmp) == 0))
1933 			return ((Sym *)0);
1934 
1935 		if ((sip->si_flags & SYMINFO_FLG_FILTER) ||
1936 		    ((sip->si_flags & SYMINFO_FLG_AUXILIARY) &&
1937 		    SYMAFLTRCNT(ilmp))) {
1938 			Sym *	fsym;
1939 
1940 			/*
1941 			 * This symbol has an associated filtee.  Lookup the
1942 			 * symbol in the filtee, and if it is found return it.
1943 			 * If the symbol doesn't exist, and this is a standard
1944 			 * filter, return an error, otherwise fall through to
1945 			 * catch any object filtering that may be available.
1946 			 */
1947 			if ((fsym = elf_lookup_filtee(slp, dlmp, binfo,
1948 			    sip->si_boundto)) != 0)
1949 				return (fsym);
1950 			if (sip->si_flags & SYMINFO_FLG_FILTER)
1951 				return ((Sym *)0);
1952 		}
1953 	}
1954 
1955 	/*
1956 	 * Determine if this object provides global filtering.
1957 	 */
1958 	if (flags1 & (FL1_RT_OBJSFLTR | FL1_RT_OBJAFLTR)) {
1959 		Sym *	fsym;
1960 
1961 		if (OBJFLTRNDX(ilmp) != FLTR_DISABLED) {
1962 			/*
1963 			 * This object has an associated filtee.  Lookup the
1964 			 * symbol in the filtee, and if it is found return it.
1965 			 * If the symbol doesn't exist, and this is a standard
1966 			 * filter, return and error, otherwise return the symbol
1967 			 * within the filter itself.
1968 			 */
1969 			if ((fsym = elf_lookup_filtee(slp, dlmp, binfo,
1970 			    OBJFLTRNDX(ilmp))) != 0)
1971 				return (fsym);
1972 		}
1973 
1974 		if (flags1 & FL1_RT_OBJSFLTR)
1975 			return ((Sym *)0);
1976 	}
1977 	return (sym);
1978 }
1979 
1980 /*
1981  * Create a new Rt_map structure for an ELF object and initialize
1982  * all values.
1983  */
1984 Rt_map *
1985 elf_new_lm(Lm_list *lml, const char *pname, const char *oname, Dyn *ld,
1986     ulong_t addr, ulong_t etext, Aliste lmco, ulong_t msize, ulong_t entry,
1987     ulong_t paddr, ulong_t padimsize, Mmap *mmaps, uint_t mmapcnt)
1988 {
1989 	Rt_map		*lmp;
1990 	ulong_t		base, fltr = 0, audit = 0, cfile = 0, crle = 0;
1991 	Xword		rpath = 0;
1992 	Ehdr		*ehdr = (Ehdr *)addr;
1993 
1994 	DBG_CALL(Dbg_file_elf(lml, pname, (ulong_t)ld, addr, msize, entry,
1995 	    lml->lm_lmidstr, lmco));
1996 
1997 	/*
1998 	 * Allocate space for the link-map and private elf information.  Once
1999 	 * these are allocated and initialized, we can use remove_so(0, lmp) to
2000 	 * tear down the link-map should any failures occur.
2001 	 */
2002 	if ((lmp = calloc(sizeof (Rt_map), 1)) == 0)
2003 		return (0);
2004 	if ((ELFPRV(lmp) = calloc(sizeof (Rt_elfp), 1)) == 0) {
2005 		free(lmp);
2006 		return (0);
2007 	}
2008 
2009 	/*
2010 	 * All fields not filled in were set to 0 by calloc.
2011 	 */
2012 	ORIGNAME(lmp) = PATHNAME(lmp) = NAME(lmp) = (char *)pname;
2013 	DYN(lmp) = ld;
2014 	ADDR(lmp) = addr;
2015 	MSIZE(lmp) = msize;
2016 	ENTRY(lmp) = (Addr)entry;
2017 	SYMINTP(lmp) = elf_find_sym;
2018 	ETEXT(lmp) = etext;
2019 	FCT(lmp) = &elf_fct;
2020 	LIST(lmp) = lml;
2021 	PADSTART(lmp) = paddr;
2022 	PADIMLEN(lmp) = padimsize;
2023 	THREADID(lmp) = rt_thr_self();
2024 	OBJFLTRNDX(lmp) = FLTR_DISABLED;
2025 	SORTVAL(lmp) = -1;
2026 
2027 	MMAPS(lmp) = mmaps;
2028 	MMAPCNT(lmp) = mmapcnt;
2029 	ASSERT(mmapcnt != 0);
2030 
2031 	/*
2032 	 * If this is a shared object, add the base address to each address.
2033 	 * if this is an executable, use address as is.
2034 	 */
2035 	if (ehdr->e_type == ET_EXEC) {
2036 		base = 0;
2037 		FLAGS(lmp) |= FLG_RT_FIXED;
2038 	} else
2039 		base = addr;
2040 
2041 	/*
2042 	 * Fill in rest of the link map entries with information from the file's
2043 	 * dynamic structure.
2044 	 */
2045 	if (ld) {
2046 		uint_t		dyncnt = 0;
2047 		Xword		pltpadsz = 0;
2048 		Rti_desc	*rti;
2049 
2050 		/* CSTYLED */
2051 		for ( ; ld->d_tag != DT_NULL; ++ld, dyncnt++) {
2052 			switch ((Xword)ld->d_tag) {
2053 			case DT_SYMTAB:
2054 				SYMTAB(lmp) = (void *)(ld->d_un.d_ptr + base);
2055 				break;
2056 			case DT_SUNW_SYMTAB:
2057 				SUNWSYMTAB(lmp) =
2058 				    (void *)(ld->d_un.d_ptr + base);
2059 				break;
2060 			case DT_SUNW_SYMSZ:
2061 				SUNWSYMSZ(lmp) = ld->d_un.d_val;
2062 				break;
2063 			case DT_STRTAB:
2064 				STRTAB(lmp) = (void *)(ld->d_un.d_ptr + base);
2065 				break;
2066 			case DT_SYMENT:
2067 				SYMENT(lmp) = ld->d_un.d_val;
2068 				break;
2069 			case DT_FEATURE_1:
2070 				ld->d_un.d_val |= DTF_1_PARINIT;
2071 				if (ld->d_un.d_val & DTF_1_CONFEXP)
2072 					crle = 1;
2073 				break;
2074 			case DT_MOVESZ:
2075 				MOVESZ(lmp) = ld->d_un.d_val;
2076 				FLAGS(lmp) |= FLG_RT_MOVE;
2077 				break;
2078 			case DT_MOVEENT:
2079 				MOVEENT(lmp) = ld->d_un.d_val;
2080 				break;
2081 			case DT_MOVETAB:
2082 				MOVETAB(lmp) = (void *)(ld->d_un.d_ptr + base);
2083 				break;
2084 			case DT_REL:
2085 			case DT_RELA:
2086 				/*
2087 				 * At this time we can only handle 1 type of
2088 				 * relocation per object.
2089 				 */
2090 				REL(lmp) = (void *)(ld->d_un.d_ptr + base);
2091 				break;
2092 			case DT_RELSZ:
2093 			case DT_RELASZ:
2094 				RELSZ(lmp) = ld->d_un.d_val;
2095 				break;
2096 			case DT_RELENT:
2097 			case DT_RELAENT:
2098 				RELENT(lmp) = ld->d_un.d_val;
2099 				break;
2100 			case DT_RELCOUNT:
2101 			case DT_RELACOUNT:
2102 				RELACOUNT(lmp) = (uint_t)ld->d_un.d_val;
2103 				break;
2104 			case DT_TEXTREL:
2105 				FLAGS1(lmp) |= FL1_RT_TEXTREL;
2106 				break;
2107 			case DT_HASH:
2108 				HASH(lmp) = (uint_t *)(ld->d_un.d_ptr + base);
2109 				break;
2110 			case DT_PLTGOT:
2111 				PLTGOT(lmp) = (uint_t *)(ld->d_un.d_ptr + base);
2112 				break;
2113 			case DT_PLTRELSZ:
2114 				PLTRELSZ(lmp) = ld->d_un.d_val;
2115 				break;
2116 			case DT_JMPREL:
2117 				JMPREL(lmp) = (void *)(ld->d_un.d_ptr + base);
2118 				break;
2119 			case DT_INIT:
2120 				if (ld->d_un.d_ptr != NULL)
2121 					INIT(lmp) =
2122 					    (void (*)())(ld->d_un.d_ptr + base);
2123 				break;
2124 			case DT_FINI:
2125 				if (ld->d_un.d_ptr != NULL)
2126 					FINI(lmp) =
2127 					    (void (*)())(ld->d_un.d_ptr + base);
2128 				break;
2129 			case DT_INIT_ARRAY:
2130 				INITARRAY(lmp) = (Addr *)(ld->d_un.d_ptr +
2131 				    base);
2132 				break;
2133 			case DT_INIT_ARRAYSZ:
2134 				INITARRAYSZ(lmp) = (uint_t)ld->d_un.d_val;
2135 				break;
2136 			case DT_FINI_ARRAY:
2137 				FINIARRAY(lmp) = (Addr *)(ld->d_un.d_ptr +
2138 				    base);
2139 				break;
2140 			case DT_FINI_ARRAYSZ:
2141 				FINIARRAYSZ(lmp) = (uint_t)ld->d_un.d_val;
2142 				break;
2143 			case DT_PREINIT_ARRAY:
2144 				PREINITARRAY(lmp) = (Addr *)(ld->d_un.d_ptr +
2145 				    base);
2146 				break;
2147 			case DT_PREINIT_ARRAYSZ:
2148 				PREINITARRAYSZ(lmp) = (uint_t)ld->d_un.d_val;
2149 				break;
2150 			case DT_RPATH:
2151 			case DT_RUNPATH:
2152 				rpath = ld->d_un.d_val;
2153 				break;
2154 			case DT_FILTER:
2155 				fltr = ld->d_un.d_val;
2156 				OBJFLTRNDX(lmp) = dyncnt;
2157 				FLAGS1(lmp) |= FL1_RT_OBJSFLTR;
2158 				break;
2159 			case DT_AUXILIARY:
2160 				if (!(rtld_flags & RT_FL_NOAUXFLTR)) {
2161 					fltr = ld->d_un.d_val;
2162 					OBJFLTRNDX(lmp) = dyncnt;
2163 				}
2164 				FLAGS1(lmp) |= FL1_RT_OBJAFLTR;
2165 				break;
2166 			case DT_SUNW_FILTER:
2167 				SYMSFLTRCNT(lmp)++;
2168 				FLAGS1(lmp) |= FL1_RT_SYMSFLTR;
2169 				break;
2170 			case DT_SUNW_AUXILIARY:
2171 				if (!(rtld_flags & RT_FL_NOAUXFLTR)) {
2172 					SYMAFLTRCNT(lmp)++;
2173 				}
2174 				FLAGS1(lmp) |= FL1_RT_SYMAFLTR;
2175 				break;
2176 			case DT_DEPAUDIT:
2177 				if (!(rtld_flags & RT_FL_NOAUDIT))
2178 					audit = ld->d_un.d_val;
2179 				break;
2180 			case DT_CONFIG:
2181 				cfile = ld->d_un.d_val;
2182 				break;
2183 			case DT_DEBUG:
2184 				/*
2185 				 * DT_DEBUG entries are only created in
2186 				 * dynamic objects that require an interpretor
2187 				 * (ie. all dynamic executables and some shared
2188 				 * objects), and provide for a hand-shake with
2189 				 * debuggers.  This entry is initialized to
2190 				 * zero by the link-editor.  If a debugger has
2191 				 * us and updated this entry set the debugger
2192 				 * flag, and finish initializing the debugging
2193 				 * structure (see setup() also).  Switch off any
2194 				 * configuration object use as most debuggers
2195 				 * can't handle fixed dynamic executables as
2196 				 * dependencies, and we can't handle requests
2197 				 * like object padding for alternative objects.
2198 				 */
2199 				if (ld->d_un.d_ptr)
2200 					rtld_flags |=
2201 					    (RT_FL_DEBUGGER | RT_FL_NOOBJALT);
2202 				ld->d_un.d_ptr = (Addr)&r_debug;
2203 				break;
2204 			case DT_VERNEED:
2205 				VERNEED(lmp) = (Verneed *)(ld->d_un.d_ptr +
2206 				    base);
2207 				break;
2208 			case DT_VERNEEDNUM:
2209 				/* LINTED */
2210 				VERNEEDNUM(lmp) = (int)ld->d_un.d_val;
2211 				break;
2212 			case DT_VERDEF:
2213 				VERDEF(lmp) = (Verdef *)(ld->d_un.d_ptr + base);
2214 				break;
2215 			case DT_VERDEFNUM:
2216 				/* LINTED */
2217 				VERDEFNUM(lmp) = (int)ld->d_un.d_val;
2218 				break;
2219 			case DT_BIND_NOW:
2220 				if ((ld->d_un.d_val & DF_BIND_NOW) &&
2221 				    ((rtld_flags2 & RT_FL2_BINDLAZY) == 0)) {
2222 					MODE(lmp) |= RTLD_NOW;
2223 					MODE(lmp) &= ~RTLD_LAZY;
2224 				}
2225 				break;
2226 			case DT_FLAGS:
2227 				if (ld->d_un.d_val & DF_SYMBOLIC)
2228 					FLAGS1(lmp) |= FL1_RT_SYMBOLIC;
2229 				if (ld->d_un.d_val & DF_TEXTREL)
2230 					FLAGS1(lmp) |= FL1_RT_TEXTREL;
2231 				if ((ld->d_un.d_val & DF_BIND_NOW) &&
2232 				    ((rtld_flags2 & RT_FL2_BINDLAZY) == 0)) {
2233 					MODE(lmp) |= RTLD_NOW;
2234 					MODE(lmp) &= ~RTLD_LAZY;
2235 				}
2236 				/*
2237 				 * Capture any static TLS use, and enforce that
2238 				 * this object be non-deletable.
2239 				 */
2240 				if (ld->d_un.d_val & DF_STATIC_TLS) {
2241 					FLAGS1(lmp) |= FL1_RT_TLSSTAT;
2242 					MODE(lmp) |= RTLD_NODELETE;
2243 				}
2244 				break;
2245 			case DT_FLAGS_1:
2246 				if (ld->d_un.d_val & DF_1_DISPRELPND)
2247 					FLAGS1(lmp) |= FL1_RT_DISPREL;
2248 				if (ld->d_un.d_val & DF_1_GROUP)
2249 					FLAGS(lmp) |=
2250 					    (FLG_RT_SETGROUP | FLG_RT_HANDLE);
2251 				if ((ld->d_un.d_val & DF_1_NOW) &&
2252 				    ((rtld_flags2 & RT_FL2_BINDLAZY) == 0)) {
2253 					MODE(lmp) |= RTLD_NOW;
2254 					MODE(lmp) &= ~RTLD_LAZY;
2255 				}
2256 				if (ld->d_un.d_val & DF_1_NODELETE)
2257 					MODE(lmp) |= RTLD_NODELETE;
2258 				if (ld->d_un.d_val & DF_1_INITFIRST)
2259 					FLAGS(lmp) |= FLG_RT_INITFRST;
2260 				if (ld->d_un.d_val & DF_1_NOOPEN)
2261 					FLAGS(lmp) |= FLG_RT_NOOPEN;
2262 				if (ld->d_un.d_val & DF_1_LOADFLTR)
2263 					FLAGS(lmp) |= FLG_RT_LOADFLTR;
2264 				if (ld->d_un.d_val & DF_1_NODUMP)
2265 					FLAGS(lmp) |= FLG_RT_NODUMP;
2266 				if (ld->d_un.d_val & DF_1_CONFALT)
2267 					crle = 1;
2268 				if (ld->d_un.d_val & DF_1_DIRECT)
2269 					FLAGS1(lmp) |= FL1_RT_DIRECT;
2270 				if (ld->d_un.d_val & DF_1_NODEFLIB)
2271 					FLAGS1(lmp) |= FL1_RT_NODEFLIB;
2272 				if (ld->d_un.d_val & DF_1_ENDFILTEE)
2273 					FLAGS1(lmp) |= FL1_RT_ENDFILTE;
2274 				if (ld->d_un.d_val & DF_1_TRANS)
2275 					FLAGS(lmp) |= FLG_RT_TRANS;
2276 #ifndef	EXPAND_RELATIVE
2277 				if (ld->d_un.d_val & DF_1_ORIGIN)
2278 					FLAGS1(lmp) |= FL1_RT_RELATIVE;
2279 #endif
2280 				/*
2281 				 * If this object identifies itself as an
2282 				 * interposer, but relocation processing has
2283 				 * already started, then demote it.  It's too
2284 				 * late to guarantee complete interposition.
2285 				 */
2286 				if (ld->d_un.d_val &
2287 				    (DF_1_INTERPOSE | DF_1_SYMINTPOSE)) {
2288 				    if (lml->lm_flags & LML_FLG_STARTREL) {
2289 					DBG_CALL(Dbg_util_intoolate(lmp));
2290 					if (lml->lm_flags & LML_FLG_TRC_ENABLE)
2291 					    (void) printf(
2292 						MSG_INTL(MSG_LDD_REL_ERR2),
2293 						NAME(lmp));
2294 				    } else if (ld->d_un.d_val & DF_1_INTERPOSE)
2295 					FLAGS(lmp) |= FLG_RT_OBJINTPO;
2296 				    else
2297 					FLAGS(lmp) |= FLG_RT_SYMINTPO;
2298 				}
2299 				break;
2300 			case DT_SYMINFO:
2301 				SYMINFO(lmp) = (Syminfo *)(ld->d_un.d_ptr +
2302 				    base);
2303 				break;
2304 			case DT_SYMINENT:
2305 				SYMINENT(lmp) = ld->d_un.d_val;
2306 				break;
2307 			case DT_PLTPAD:
2308 				PLTPAD(lmp) = (void *)(ld->d_un.d_ptr + base);
2309 				break;
2310 			case DT_PLTPADSZ:
2311 				pltpadsz = ld->d_un.d_val;
2312 				break;
2313 			case DT_SUNW_RTLDINF:
2314 				/*
2315 				 * Maintain a list of RTLDINFO structures.
2316 				 * Typically, libc is the only supplier, and
2317 				 * only one structure is provided.  However,
2318 				 * multiple suppliers and multiple structures
2319 				 * are supported.  For example, one structure
2320 				 * may provide thread_init, and another
2321 				 * structure may provide atexit reservations.
2322 				 */
2323 				if ((rti = alist_append(&lml->lm_rti, 0,
2324 				    sizeof (Rti_desc), AL_CNT_RTLDINFO)) == 0) {
2325 					remove_so(0, lmp);
2326 					return (0);
2327 				}
2328 				rti->rti_lmp = lmp;
2329 				rti->rti_info = (void *)(ld->d_un.d_ptr + base);
2330 				break;
2331 			case DT_SUNW_SORTENT:
2332 				SUNWSORTENT(lmp) = ld->d_un.d_val;
2333 				break;
2334 			case DT_SUNW_SYMSORT:
2335 				SUNWSYMSORT(lmp) =
2336 				    (void *)(ld->d_un.d_ptr + base);
2337 				break;
2338 			case DT_SUNW_SYMSORTSZ:
2339 				SUNWSYMSORTSZ(lmp) = ld->d_un.d_val;
2340 				break;
2341 			case DT_DEPRECATED_SPARC_REGISTER:
2342 			case M_DT_REGISTER:
2343 				FLAGS(lmp) |= FLG_RT_REGSYMS;
2344 				break;
2345 			case M_DT_PLTRESERVE:
2346 				PLTRESERVE(lmp) = (void *)(ld->d_un.d_ptr +
2347 				    base);
2348 				break;
2349 			}
2350 		}
2351 
2352 
2353 		if (PLTPAD(lmp)) {
2354 			if (pltpadsz == (Xword)0)
2355 				PLTPAD(lmp) = 0;
2356 			else
2357 				PLTPADEND(lmp) = (void *)((Addr)PLTPAD(lmp) +
2358 				    pltpadsz);
2359 		}
2360 
2361 		/*
2362 		 * Allocate Dynamic Info structure
2363 		 */
2364 		if ((DYNINFO(lmp) = calloc((size_t)dyncnt,
2365 		    sizeof (Dyninfo))) == 0) {
2366 			remove_so(0, lmp);
2367 			return (0);
2368 		}
2369 		DYNINFOCNT(lmp) = dyncnt;
2370 	}
2371 
2372 	/*
2373 	 * A dynsym contains only global functions. We want to have
2374 	 * a version of it that also includes local functions, so that
2375 	 * dladdr() will be able to report names for local functions
2376 	 * when used to generate a stack trace for a stripped file.
2377 	 * This version of the dynsym is provided via DT_SUNW_SYMTAB.
2378 	 *
2379 	 * In producing DT_SUNW_SYMTAB, ld uses a non-obvious trick
2380 	 * in order to avoid having to have two copies of the global
2381 	 * symbols held in DT_SYMTAB: The local symbols are placed in
2382 	 * a separate section than the globals in the dynsym, but the
2383 	 * linker conspires to put the data for these two sections adjacent
2384 	 * to each other. DT_SUNW_SYMTAB points at the top of the local
2385 	 * symbols, and DT_SUNW_SYMSZ is the combined length of both tables.
2386 	 *
2387 	 * If the two sections are not adjacent, then something went wrong
2388 	 * at link time. We use ASSERT to kill the process if this is
2389 	 * a debug build. In a production build, we will silently ignore
2390 	 * the presence of the .ldynsym and proceed. We can detect this
2391 	 * situation by checking to see that DT_SYMTAB lies in
2392 	 * the range given by DT_SUNW_SYMTAB/DT_SUNW_SYMSZ.
2393 	 */
2394 	if ((SUNWSYMTAB(lmp) != NULL) &&
2395 	    (((char *)SYMTAB(lmp) <= (char *)SUNWSYMTAB(lmp)) ||
2396 	    (((char *)SYMTAB(lmp) >=
2397 	    (SUNWSYMSZ(lmp) + (char *)SUNWSYMTAB(lmp)))))) {
2398 		ASSERT(0);
2399 		SUNWSYMTAB(lmp) = NULL;
2400 		SUNWSYMSZ(lmp) = 0;
2401 	}
2402 
2403 	/*
2404 	 * If configuration file use hasn't been disabled, and a configuration
2405 	 * file hasn't already been set via an environment variable, see if any
2406 	 * application specific configuration file is specified.  An LD_CONFIG
2407 	 * setting is used first, but if this image was generated via crle(1)
2408 	 * then a default configuration file is a fall-back.
2409 	 */
2410 	if ((!(rtld_flags & RT_FL_NOCFG)) && (config->c_name == 0)) {
2411 		if (cfile)
2412 			config->c_name = (const char *)(cfile +
2413 			    (char *)STRTAB(lmp));
2414 		else if (crle) {
2415 			rtld_flags |= RT_FL_CONFAPP;
2416 #ifndef	EXPAND_RELATIVE
2417 			FLAGS1(lmp) |= FL1_RT_RELATIVE;
2418 #endif
2419 		}
2420 	}
2421 
2422 	if (rpath)
2423 		RPATH(lmp) = (char *)(rpath + (char *)STRTAB(lmp));
2424 	if (fltr) {
2425 		/*
2426 		 * If this object is a global filter, duplicate the filtee
2427 		 * string name(s) so that REFNAME() is available in core files.
2428 		 * This cludge was useful for debuggers at one point, but only
2429 		 * when the filtee name was an individual full path.
2430 		 */
2431 		if ((REFNAME(lmp) = strdup(fltr + (char *)STRTAB(lmp))) == 0) {
2432 			remove_so(0, lmp);
2433 			return (0);
2434 		}
2435 	}
2436 
2437 	if (rtld_flags & RT_FL_RELATIVE)
2438 		FLAGS1(lmp) |= FL1_RT_RELATIVE;
2439 
2440 	/*
2441 	 * For Intel ABI compatibility.  It's possible that a JMPREL can be
2442 	 * specified without any other relocations (e.g. a dynamic executable
2443 	 * normally only contains .plt relocations).  If this is the case then
2444 	 * no REL, RELSZ or RELENT will have been created.  For us to be able
2445 	 * to traverse the .plt relocations under LD_BIND_NOW we need to know
2446 	 * the RELENT for these relocations.  Refer to elf_reloc() for more
2447 	 * details.
2448 	 */
2449 	if (!RELENT(lmp) && JMPREL(lmp))
2450 		RELENT(lmp) = sizeof (Rel);
2451 
2452 	/*
2453 	 * Establish any per-object auditing.  If we're establishing `main's
2454 	 * link-map its too early to go searching for audit objects so just
2455 	 * hold the object name for later (see setup()).
2456 	 */
2457 	if (audit) {
2458 		char	*cp = audit + (char *)STRTAB(lmp);
2459 
2460 		if (*cp) {
2461 			if (((AUDITORS(lmp) =
2462 			    calloc(1, sizeof (Audit_desc))) == 0) ||
2463 			    ((AUDITORS(lmp)->ad_name = strdup(cp)) == 0)) {
2464 				remove_so(0, lmp);
2465 				return (0);
2466 			}
2467 			if (lml_main.lm_head) {
2468 				if (audit_setup(lmp, AUDITORS(lmp), 0) == 0) {
2469 					remove_so(0, lmp);
2470 					return (0);
2471 				}
2472 				FLAGS1(lmp) |= AUDITORS(lmp)->ad_flags;
2473 				lml->lm_flags |= LML_FLG_LOCAUDIT;
2474 			}
2475 		}
2476 	}
2477 
2478 	if ((CONDVAR(lmp) = rt_cond_create()) == 0) {
2479 		remove_so(0, lmp);
2480 		return (0);
2481 	}
2482 	if (oname && ((append_alias(lmp, oname, 0)) == 0)) {
2483 		remove_so(0, lmp);
2484 		return (0);
2485 	}
2486 
2487 	/*
2488 	 * Add the mapped object to the end of the link map list.
2489 	 */
2490 	lm_append(lml, lmco, lmp);
2491 	return (lmp);
2492 }
2493 
2494 /*
2495  * Assign hardware/software capabilities.
2496  */
2497 void
2498 cap_assign(Cap *cap, Rt_map *lmp)
2499 {
2500 	while (cap->c_tag != CA_SUNW_NULL) {
2501 		switch (cap->c_tag) {
2502 		case CA_SUNW_HW_1:
2503 			HWCAP(lmp) = cap->c_un.c_val;
2504 			break;
2505 		case CA_SUNW_SF_1:
2506 			SFCAP(lmp) = cap->c_un.c_val;
2507 		}
2508 		cap++;
2509 	}
2510 }
2511 
2512 /*
2513  * Map in an ELF object.
2514  * Takes an open file descriptor for the object to map and its pathname; returns
2515  * a pointer to a Rt_map structure for this object, or 0 on error.
2516  */
2517 static Rt_map *
2518 elf_map_so(Lm_list *lml, Aliste lmco, const char *pname, const char *oname,
2519     int fd)
2520 {
2521 	int		i; 		/* general temporary */
2522 	Off		memsize = 0;	/* total memory size of pathname */
2523 	Off		mentry;		/* entry point */
2524 	Ehdr		*ehdr;		/* ELF header of ld.so */
2525 	Phdr		*phdr;		/* first Phdr in file */
2526 	Phdr		*phdr0;		/* Saved first Phdr in file */
2527 	Phdr		*pptr;		/* working Phdr */
2528 	Phdr		*fph = 0;	/* first loadable Phdr */
2529 	Phdr		*lph;		/* last loadable Phdr */
2530 	Phdr		*lfph = 0;	/* last loadable (filesz != 0) Phdr */
2531 	Phdr		*lmph = 0;	/* last loadable (memsz != 0) Phdr */
2532 	Phdr		*swph = 0;	/* program header for SUNWBSS */
2533 	Phdr		*tlph = 0;	/* program header for PT_TLS */
2534 	Phdr		*unwindph = 0;	/* program header for PT_SUNW_UNWIND */
2535 	Cap		*cap = 0;	/* program header for SUNWCAP */
2536 	Dyn		*mld = 0;	/* DYNAMIC structure for pathname */
2537 	size_t		size;		/* size of elf and program headers */
2538 	caddr_t		faddr = 0;	/* mapping address of pathname */
2539 	Rt_map		*lmp;		/* link map created */
2540 	caddr_t		paddr;		/* start of padded image */
2541 	Off		plen;		/* size of image including padding */
2542 	Half		etype;
2543 	int		fixed;
2544 	Mmap		*mmaps;
2545 	uint_t		mmapcnt = 0;
2546 	Xword		align = 0;
2547 
2548 	/* LINTED */
2549 	ehdr = (Ehdr *)fmap->fm_maddr;
2550 
2551 	/*
2552 	 * If this a relocatable object then special processing is required.
2553 	 */
2554 	if ((etype = ehdr->e_type) == ET_REL)
2555 		return (elf_obj_file(lml, lmco, pname, fd));
2556 
2557 	/*
2558 	 * If this isn't a dynamic executable or shared object we can't process
2559 	 * it.  If this is a dynamic executable then all addresses are fixed.
2560 	 */
2561 	if (etype == ET_EXEC)
2562 		fixed = 1;
2563 	else if (etype == ET_DYN)
2564 		fixed = 0;
2565 	else {
2566 		eprintf(lml, ERR_ELF, MSG_INTL(MSG_GEN_BADTYPE), pname,
2567 		    conv_ehdr_type(etype, 0));
2568 		return (0);
2569 	}
2570 
2571 	/*
2572 	 * If our original mapped page was not large enough to hold all the
2573 	 * program headers remap them.
2574 	 */
2575 	size = (size_t)((char *)ehdr->e_phoff +
2576 		(ehdr->e_phnum * ehdr->e_phentsize));
2577 	if (size > fmap->fm_fsize) {
2578 		eprintf(lml, ERR_FATAL, MSG_INTL(MSG_GEN_CORTRUNC), pname);
2579 		return (0);
2580 	}
2581 	if (size > fmap->fm_msize) {
2582 		fmap_setup();
2583 		if ((fmap->fm_maddr = mmap(fmap->fm_maddr, size, PROT_READ,
2584 		    fmap->fm_mflags, fd, 0)) == MAP_FAILED) {
2585 			int	err = errno;
2586 			eprintf(lml, ERR_FATAL, MSG_INTL(MSG_SYS_MMAP), pname,
2587 			    strerror(err));
2588 			return (0);
2589 		}
2590 		fmap->fm_msize = size;
2591 		/* LINTED */
2592 		ehdr = (Ehdr *)fmap->fm_maddr;
2593 	}
2594 	/* LINTED */
2595 	phdr0 = phdr = (Phdr *)((char *)ehdr + ehdr->e_ehsize);
2596 
2597 	/*
2598 	 * Get entry point.
2599 	 */
2600 	mentry = ehdr->e_entry;
2601 
2602 	/*
2603 	 * Point at program headers and perform some basic validation.
2604 	 */
2605 	for (i = 0, pptr = phdr; i < (int)ehdr->e_phnum; i++,
2606 	    pptr = (Phdr *)((Off)pptr + ehdr->e_phentsize)) {
2607 		if ((pptr->p_type == PT_LOAD) ||
2608 		    (pptr->p_type == PT_SUNWBSS)) {
2609 
2610 			if (fph == 0) {
2611 				fph = pptr;
2612 			/* LINTED argument lph is initialized in first pass */
2613 			} else if (pptr->p_vaddr <= lph->p_vaddr) {
2614 				eprintf(lml, ERR_ELF,
2615 				    MSG_INTL(MSG_GEN_INVPRGHDR), pname);
2616 				return (0);
2617 			}
2618 
2619 			lph = pptr;
2620 
2621 			if (pptr->p_memsz)
2622 				lmph = pptr;
2623 			if (pptr->p_filesz)
2624 				lfph = pptr;
2625 			if (pptr->p_type == PT_SUNWBSS)
2626 				swph = pptr;
2627 			if (pptr->p_align > align)
2628 				align = pptr->p_align;
2629 
2630 		} else if (pptr->p_type == PT_DYNAMIC) {
2631 			mld = (Dyn *)(pptr->p_vaddr);
2632 		} else if ((pptr->p_type == PT_TLS) && pptr->p_memsz) {
2633 			tlph = pptr;
2634 		} else if (pptr->p_type == PT_SUNWCAP) {
2635 			cap = (Cap *)(pptr->p_vaddr);
2636 		} else if (pptr->p_type == PT_SUNW_UNWIND) {
2637 			unwindph = pptr;
2638 		}
2639 	}
2640 
2641 #if defined(MAP_ALIGN)
2642 	/*
2643 	 * Make sure the maximum page alignment is a power of 2 >= the system
2644 	 * page size, for use with MAP_ALIGN.
2645 	 */
2646 	align = M_PROUND(align);
2647 #endif
2648 
2649 	/*
2650 	 * We'd better have at least one loadable segment, together with some
2651 	 * specified file and memory size.
2652 	 */
2653 	if ((fph == 0) || (lmph == 0) || (lfph == 0)) {
2654 		eprintf(lml, ERR_ELF, MSG_INTL(MSG_GEN_NOLOADSEG), pname);
2655 		return (0);
2656 	}
2657 
2658 	/*
2659 	 * Check that the files size accounts for the loadable sections
2660 	 * we're going to map in (failure to do this may cause spurious
2661 	 * bus errors if we're given a truncated file).
2662 	 */
2663 	if (fmap->fm_fsize < ((size_t)lfph->p_offset + lfph->p_filesz)) {
2664 		eprintf(lml, ERR_FATAL, MSG_INTL(MSG_GEN_CORTRUNC), pname);
2665 		return (0);
2666 	}
2667 
2668 	/*
2669 	 * Memsize must be page rounded so that if we add object padding
2670 	 * at the end it will start at the beginning of a page.
2671 	 */
2672 	plen = memsize = M_PROUND((lmph->p_vaddr + lmph->p_memsz) -
2673 	    M_PTRUNC((ulong_t)fph->p_vaddr));
2674 
2675 	/*
2676 	 * Determine if an existing mapping is acceptable.
2677 	 */
2678 	if (interp && (lml->lm_flags & LML_FLG_BASELM) &&
2679 	    (strcmp(pname, interp->i_name) == 0)) {
2680 		/*
2681 		 * If this is the interpreter then it has already been mapped
2682 		 * and we have the address so don't map it again.  Note that
2683 		 * the common occurrence of a reference to the interpretor
2684 		 * (libdl -> ld.so.1) will have been caught during filter
2685 		 * initialization (see elf_lookup_filtee()).  However, some
2686 		 * ELF implementations are known to record libc.so.1 as the
2687 		 * interpretor, and thus this test catches this behavior.
2688 		 */
2689 		paddr = faddr = interp->i_faddr;
2690 
2691 	} else if ((fixed == 0) && (r_debug.rtd_objpad == 0) &&
2692 	    (memsize <= fmap->fm_msize) && ((fph->p_flags & PF_W) == 0) &&
2693 	    (fph->p_filesz == fph->p_memsz) &&
2694 	    (((Xword)fmap->fm_maddr % align) == 0)) {
2695 		/*
2696 		 * If the mapping required has already been established from
2697 		 * the initial page we don't need to do anything more.  Reset
2698 		 * the fmap address so then any later files start a new fmap.
2699 		 * This is really an optimization for filters, such as libdl.so,
2700 		 * which should only require one page.
2701 		 */
2702 		paddr = faddr = fmap->fm_maddr;
2703 		fmap->fm_maddr = 0;
2704 		fmap_setup();
2705 	}
2706 
2707 	/*
2708 	 * Allocate a mapping array to retain mapped segment information.
2709 	 */
2710 	if ((mmaps = calloc(ehdr->e_phnum, sizeof (Mmap))) == 0)
2711 		return (0);
2712 
2713 	/*
2714 	 * If we're reusing an existing mapping determine the objects etext
2715 	 * address.  Otherwise map the file (which will calculate the etext
2716 	 * address as part of the mapping process).
2717 	 */
2718 	if (faddr) {
2719 		caddr_t	base;
2720 
2721 		if (fixed)
2722 			base = 0;
2723 		else
2724 			base = faddr;
2725 
2726 		/* LINTED */
2727 		phdr0 = phdr = (Phdr *)((char *)faddr + ehdr->e_ehsize);
2728 
2729 		for (i = 0, pptr = phdr; i < (int)ehdr->e_phnum; i++,
2730 		    pptr = (Phdr *)((Off)pptr + ehdr->e_phentsize)) {
2731 			if (pptr->p_type != PT_LOAD)
2732 				continue;
2733 
2734 			mmaps[mmapcnt].m_vaddr = (pptr->p_vaddr + base);
2735 			mmaps[mmapcnt].m_msize = pptr->p_memsz;
2736 			mmaps[mmapcnt].m_fsize = pptr->p_filesz;
2737 			mmaps[mmapcnt].m_perm = (PROT_READ | PROT_EXEC);
2738 			mmapcnt++;
2739 
2740 			if (!(pptr->p_flags & PF_W)) {
2741 				fmap->fm_etext = (ulong_t)pptr->p_vaddr +
2742 				    (ulong_t)pptr->p_memsz +
2743 				    (ulong_t)(fixed ? 0 : faddr);
2744 			}
2745 		}
2746 	} else {
2747 		/*
2748 		 * Map the file.
2749 		 */
2750 		if (!(faddr = elf_map_it(lml, pname, memsize, ehdr, fph, lph,
2751 		    &phdr, &paddr, &plen, fixed, fd, align, mmaps, &mmapcnt)))
2752 			return (0);
2753 	}
2754 
2755 	/*
2756 	 * Calculate absolute base addresses and entry points.
2757 	 */
2758 	if (!fixed) {
2759 		if (mld)
2760 			/* LINTED */
2761 			mld = (Dyn *)((Off)mld + faddr);
2762 		if (cap)
2763 			/* LINTED */
2764 			cap = (Cap *)((Off)cap + faddr);
2765 		mentry += (Off)faddr;
2766 	}
2767 
2768 	/*
2769 	 * Create new link map structure for newly mapped shared object.
2770 	 */
2771 	if (!(lmp = elf_new_lm(lml, pname, oname, mld, (ulong_t)faddr,
2772 	    fmap->fm_etext, lmco, memsize, mentry, (ulong_t)paddr, plen, mmaps,
2773 	    mmapcnt))) {
2774 		(void) munmap((caddr_t)faddr, memsize);
2775 		return (0);
2776 	}
2777 
2778 	/*
2779 	 * Start the system loading in the ELF information we'll be processing.
2780 	 */
2781 	if (REL(lmp)) {
2782 		(void) madvise((void *)ADDR(lmp), (uintptr_t)REL(lmp) +
2783 		    (uintptr_t)RELSZ(lmp) - (uintptr_t)ADDR(lmp),
2784 		    MADV_WILLNEED);
2785 	}
2786 
2787 	/*
2788 	 * If this shared object contains any special segments, record them.
2789 	 */
2790 	if (swph) {
2791 		FLAGS(lmp) |= FLG_RT_SUNWBSS;
2792 		SUNWBSS(lmp) = phdr + (swph - phdr0);
2793 	}
2794 	if (tlph && (tls_assign(lml, lmp, (phdr + (tlph - phdr0))) == 0)) {
2795 		remove_so(lml, lmp);
2796 		return (0);
2797 	}
2798 
2799 	if (unwindph)
2800 		PTUNWIND(lmp) = phdr + (unwindph - phdr0);
2801 
2802 	if (cap)
2803 		cap_assign(cap, lmp);
2804 
2805 	return (lmp);
2806 }
2807 
2808 /*
2809  * Function to correct protection settings.  Segments are all mapped initially
2810  * with permissions as given in the segment header.  We need to turn on write
2811  * permissions on a text segment if there are any relocations against that
2812  * segment, and them turn write permission back off again before returning
2813  * control to the user.  This function turns the permission on or off depending
2814  * on the value of the argument.
2815  */
2816 int
2817 elf_set_prot(Rt_map *lmp, int permission)
2818 {
2819 	Mmap	*mmaps;
2820 
2821 	/*
2822 	 * If this is an allocated image (ie. a relocatable object) we can't
2823 	 * mprotect() anything.
2824 	 */
2825 	if (FLAGS(lmp) & FLG_RT_IMGALLOC)
2826 		return (1);
2827 
2828 	DBG_CALL(Dbg_file_prot(lmp, permission));
2829 
2830 	for (mmaps = MMAPS(lmp); mmaps->m_vaddr; mmaps++) {
2831 		if (mmaps->m_perm & PROT_WRITE)
2832 			continue;
2833 
2834 		if (mprotect(mmaps->m_vaddr, mmaps->m_msize,
2835 		    (mmaps->m_perm | permission)) == -1) {
2836 			int	err = errno;
2837 			eprintf(LIST(lmp), ERR_FATAL, MSG_INTL(MSG_SYS_MPROT),
2838 			    NAME(lmp), strerror(err));
2839 			return (0);
2840 		}
2841 	}
2842 	return (1);
2843 }
2844 
2845 /*
2846  * Build full pathname of shared object from given directory name and filename.
2847  */
2848 static char *
2849 elf_get_so(const char *dir, const char *file)
2850 {
2851 	static char	pname[PATH_MAX];
2852 
2853 	(void) snprintf(pname, PATH_MAX, MSG_ORIG(MSG_FMT_PATH), dir, file);
2854 	return (pname);
2855 }
2856 
2857 /*
2858  * The copy relocation is recorded in a copy structure which will be applied
2859  * after all other relocations are carried out.  This provides for copying data
2860  * that must be relocated itself (ie. pointers in shared objects).  This
2861  * structure also provides a means of binding RTLD_GROUP dependencies to any
2862  * copy relocations that have been taken from any group members.
2863  *
2864  * If the size of the .bss area available for the copy information is not the
2865  * same as the source of the data inform the user if we're under ldd(1) control
2866  * (this checking was only established in 5.3, so by only issuing an error via
2867  * ldd(1) we maintain the standard set by previous releases).
2868  */
2869 int
2870 elf_copy_reloc(char *name, Sym *rsym, Rt_map *rlmp, void *radd, Sym *dsym,
2871     Rt_map *dlmp, const void *dadd)
2872 {
2873 	Rel_copy	rc;
2874 	Lm_list		*lml = LIST(rlmp);
2875 
2876 	rc.r_name = name;
2877 	rc.r_rsym = rsym;		/* the new reference symbol and its */
2878 	rc.r_rlmp = rlmp;		/*	associated link-map */
2879 	rc.r_dlmp = dlmp;		/* the defining link-map */
2880 	rc.r_dsym = dsym;		/* the original definition */
2881 	rc.r_radd = radd;
2882 	rc.r_dadd = dadd;
2883 
2884 	if (rsym->st_size > dsym->st_size)
2885 		rc.r_size = (size_t)dsym->st_size;
2886 	else
2887 		rc.r_size = (size_t)rsym->st_size;
2888 
2889 	if (alist_append(&COPY(dlmp), &rc, sizeof (Rel_copy),
2890 	    AL_CNT_COPYREL) == 0) {
2891 		if (!(lml->lm_flags & LML_FLG_TRC_WARN))
2892 			return (0);
2893 		else
2894 			return (1);
2895 	}
2896 	if (!(FLAGS1(dlmp) & FL1_RT_COPYTOOK)) {
2897 		if (alist_append(&COPY(rlmp), &dlmp,
2898 		    sizeof (Rt_map *), AL_CNT_COPYREL) == 0) {
2899 			if (!(lml->lm_flags & LML_FLG_TRC_WARN))
2900 				return (0);
2901 			else
2902 				return (1);
2903 		}
2904 		FLAGS1(dlmp) |= FL1_RT_COPYTOOK;
2905 	}
2906 
2907 	/*
2908 	 * If we are tracing (ldd), warn the user if
2909 	 *	1) the size from the reference symbol differs from the
2910 	 *	   copy definition. We can only copy as much data as the
2911 	 *	   reference (dynamic executables) entry allows.
2912 	 *	2) the copy definition has STV_PROTECTED visibility.
2913 	 */
2914 	if (lml->lm_flags & LML_FLG_TRC_WARN) {
2915 		if (rsym->st_size != dsym->st_size) {
2916 			(void) printf(MSG_INTL(MSG_LDD_CPY_SIZDIF),
2917 			    _conv_reloc_type(M_R_COPY), demangle(name),
2918 			    NAME(rlmp), EC_XWORD(rsym->st_size),
2919 			    NAME(dlmp), EC_XWORD(dsym->st_size));
2920 			if (rsym->st_size > dsym->st_size)
2921 				(void) printf(MSG_INTL(MSG_LDD_CPY_INSDATA),
2922 				    NAME(dlmp));
2923 			else
2924 				(void) printf(MSG_INTL(MSG_LDD_CPY_DATRUNC),
2925 				    NAME(rlmp));
2926 		}
2927 
2928 		if (ELF_ST_VISIBILITY(dsym->st_other) == STV_PROTECTED) {
2929 			(void) printf(MSG_INTL(MSG_LDD_CPY_PROT),
2930 			    _conv_reloc_type(M_R_COPY), demangle(name),
2931 				NAME(dlmp));
2932 		}
2933 	}
2934 
2935 	DBG_CALL(Dbg_reloc_apply_val(lml, ELF_DBG_RTLD, (Xword)radd,
2936 	    (Xword)rc.r_size));
2937 	return (1);
2938 }
2939 
2940 /*
2941  * Determine the symbol location of an address within a link-map.  Look for
2942  * the nearest symbol (whose value is less than or equal to the required
2943  * address).  This is the object specific part of dladdr().
2944  */
2945 static void
2946 elf_dladdr(ulong_t addr, Rt_map *lmp, Dl_info *dlip, void **info, int flags)
2947 {
2948 	ulong_t		ndx, cnt, base, _value;
2949 	Sym		*sym, *_sym = NULL;
2950 	const char	*str;
2951 	int		_flags;
2952 	uint_t		*dynaddr_ndx;
2953 	uint_t		dynaddr_n = 0;
2954 	ulong_t		value;
2955 
2956 	/*
2957 	 * If SUNWSYMTAB() is non-NULL, then it sees a special version of
2958 	 * the dynsym that starts with any local function symbols that exist in
2959 	 * the library and then moves to the data held in SYMTAB(). In this
2960 	 * case, SUNWSYMSZ tells us how long the symbol table is. The
2961 	 * availability of local function symbols will enhance the results
2962 	 * we can provide.
2963 	 *
2964 	 * If SUNWSYMTAB() is non-NULL, then there might also be a
2965 	 * SUNWSYMSORT() vector associated with it. SUNWSYMSORT() contains
2966 	 * an array of indices into SUNWSYMTAB, sorted by increasing
2967 	 * address. We can use this to do an O(log N) search instead of a
2968 	 * brute force search.
2969 	 *
2970 	 * If SUNWSYMTAB() is NULL, then SYMTAB() references a dynsym that
2971 	 * contains only global symbols. In that case, the length of
2972 	 * the symbol table comes from the nchain field of the related
2973 	 * symbol lookup hash table.
2974 	 */
2975 	str = STRTAB(lmp);
2976 	if (SUNWSYMSZ(lmp) == NULL) {
2977 		sym = SYMTAB(lmp);
2978 		/*
2979 		 * If we don't have a .hash table there are no symbols
2980 		 * to look at.
2981 		 */
2982 		if (HASH(lmp) == 0)
2983 			return;
2984 		cnt = HASH(lmp)[1];
2985 	} else {
2986 		sym = SUNWSYMTAB(lmp);
2987 		cnt = SUNWSYMSZ(lmp) / SYMENT(lmp);
2988 		dynaddr_ndx = SUNWSYMSORT(lmp);
2989 		if (dynaddr_ndx != NULL)
2990 			dynaddr_n = SUNWSYMSORTSZ(lmp) / SUNWSORTENT(lmp);
2991 	}
2992 
2993 	if (FLAGS(lmp) & FLG_RT_FIXED)
2994 		base = 0;
2995 	else
2996 		base = ADDR(lmp);
2997 
2998 	if (dynaddr_n > 0) {		/* Binary search */
2999 		long	low = 0, low_bnd;
3000 		long	high = dynaddr_n - 1, high_bnd;
3001 		long	mid;
3002 		Sym	*mid_sym;
3003 
3004 		/*
3005 		 * Note that SUNWSYMSORT only contains symbols types that
3006 		 * supply memory addresses, so there's no need to check and
3007 		 * filter out any other types.
3008 		 */
3009 		low_bnd = low;
3010 		high_bnd = high;
3011 		while (low <= high) {
3012 			mid = (low + high) / 2;
3013 			mid_sym = &sym[dynaddr_ndx[mid]];
3014 			value = mid_sym->st_value + base;
3015 			if (addr < value) {
3016 				if ((sym[dynaddr_ndx[high]].st_value + base) >=
3017 				    addr)
3018 					high_bnd = high;
3019 				high = mid - 1;
3020 			} else if (addr > value) {
3021 				if ((sym[dynaddr_ndx[low]].st_value + base) <=
3022 				    addr)
3023 					low_bnd = low;
3024 				low = mid + 1;
3025 			} else {
3026 				_sym = mid_sym;
3027 				_value = value;
3028 				break;
3029 			}
3030 		}
3031 		/*
3032 		 * If the above didn't find it exactly, then we must
3033 		 * return the closest symbol with a value that doesn't
3034 		 * exceed the one we are looking for. If that symbol exists,
3035 		 * it will lie in the range bounded by low_bnd and
3036 		 * high_bnd. This is a linear search, but a short one.
3037 		 */
3038 		if (_sym == NULL) {
3039 			for (mid = low_bnd; mid <= high_bnd; mid++) {
3040 				mid_sym = &sym[dynaddr_ndx[mid]];
3041 				value = mid_sym->st_value + base;
3042 				if (addr >= value) {
3043 					_sym = mid_sym;
3044 					_value = value;
3045 				} else {
3046 					break;
3047 				}
3048 			}
3049 		}
3050 	} else {			/* Linear search */
3051 		for (_value = 0, sym++, ndx = 1; ndx < cnt; ndx++, sym++) {
3052 			/*
3053 			 * Skip expected symbol types that are not functions
3054 			 * or data:
3055 			 *	- A symbol table starts with an undefined symbol
3056 			 *		in slot 0. If we are using SUNWSYMTAB(),
3057 			 *		there will be a second undefined symbol
3058 			 *		right before the globals.
3059 			 *	- The local part of SUNWSYMTAB() contains a
3060 			 *		series of function symbols. Each section
3061 			 *		starts with an initial STT_FILE symbol.
3062 			 */
3063 			if ((sym->st_shndx == SHN_UNDEF) ||
3064 			    (ELF_ST_TYPE(sym->st_info) == STT_FILE))
3065 				continue;
3066 
3067 			value = sym->st_value + base;
3068 			if (value > addr)
3069 				continue;
3070 			if (value < _value)
3071 				continue;
3072 
3073 			_sym = sym;
3074 			_value = value;
3075 
3076 			/*
3077 			 * Note, because we accept local and global symbols
3078 			 * we could find a section symbol that matches the
3079 			 * associated address, which means that the symbol
3080 			 * name will be null.  In this case continue the
3081 			 * search in case we can find a global symbol of
3082 			 * the same value.
3083 			 */
3084 			if ((value == addr) &&
3085 			    (ELF_ST_TYPE(sym->st_info) != STT_SECTION))
3086 				break;
3087 		}
3088 	}
3089 
3090 	_flags = flags & RTLD_DL_MASK;
3091 	if (_sym) {
3092 		if (_flags == RTLD_DL_SYMENT)
3093 			*info = (void *)_sym;
3094 		else if (_flags == RTLD_DL_LINKMAP)
3095 			*info = (void *)lmp;
3096 
3097 		dlip->dli_sname = str + _sym->st_name;
3098 		dlip->dli_saddr = (void *)_value;
3099 	} else {
3100 		/*
3101 		 * addr lies between the beginning of the mapped segment and
3102 		 * the first global symbol. We have no symbol to return
3103 		 * and the caller requires one. We use _START_, the base
3104 		 * address of the mapping.
3105 		 */
3106 
3107 		if (_flags == RTLD_DL_SYMENT) {
3108 			/*
3109 			 * An actual symbol struct is needed, so we
3110 			 * construct one for _START_. To do this in a
3111 			 * fully accurate way requires a different symbol
3112 			 * for each mapped segment. This requires the
3113 			 * use of dynamic memory and a mutex. That's too much
3114 			 * plumbing for a fringe case of limited importance.
3115 			 *
3116 			 * Fortunately, we can simplify:
3117 			 *    - Only the st_size and st_info fields are useful
3118 			 *	outside of the linker internals. The others
3119 			 *	reference things that outside code cannot see,
3120 			 *	and can be set to 0.
3121 			 *    - It's just a label and there is no size
3122 			 *	to report. So, the size should be 0.
3123 			 * This means that only st_info needs a non-zero
3124 			 * (constant) value. A static struct will suffice.
3125 			 * It must be const (readonly) so the caller can't
3126 			 * change its meaning for subsequent callers.
3127 			 */
3128 			static const Sym fsym = { 0, 0, 0,
3129 				ELF_ST_INFO(STB_LOCAL, STT_OBJECT) };
3130 			*info = (void *) &fsym;
3131 		}
3132 
3133 		dlip->dli_sname = MSG_ORIG(MSG_SYM_START);
3134 		dlip->dli_saddr = (void *) ADDR(lmp);
3135 	}
3136 }
3137 
3138 static void
3139 elf_lazy_cleanup(Alist *alp)
3140 {
3141 	Rt_map	**lmpp;
3142 	Aliste	off;
3143 
3144 	/*
3145 	 * Cleanup any link-maps added to this dynamic list and free it.
3146 	 */
3147 	for (ALIST_TRAVERSE(alp, off, lmpp))
3148 		FLAGS(*lmpp) &= ~FLG_RT_DLSYM;
3149 	free(alp);
3150 }
3151 
3152 /*
3153  * This routine is called upon to search for a symbol from the dependencies of
3154  * the initial link-map.  To maintain lazy loadings goal of reducing the number
3155  * of objects mapped, any symbol search is first carried out using the objects
3156  * that already exist in the process (either on a link-map list or handle).
3157  * If a symbol can't be found, and lazy dependencies are still pending, this
3158  * routine loads the dependencies in an attempt to locate the symbol.
3159  *
3160  * Only new objects are inspected as we will have already inspected presently
3161  * loaded objects before calling this routine.  However, a new object may not
3162  * be new - although the di_lmp might be zero, the object may have been mapped
3163  * as someone elses dependency.  Thus there's a possibility of some symbol
3164  * search duplication.
3165  */
3166 
3167 Sym *
3168 elf_lazy_find_sym(Slookup *slp, Rt_map **_lmp, uint_t *binfo)
3169 {
3170 	Sym		*sym = 0;
3171 	Alist *		alist = 0;
3172 	Aliste		off;
3173 	Rt_map **	lmpp, *	lmp = slp->sl_imap;
3174 	const char	*name = slp->sl_name;
3175 
3176 	if (alist_append(&alist, &lmp, sizeof (Rt_map *), AL_CNT_LAZYFIND) == 0)
3177 		return (0);
3178 	FLAGS(lmp) |= FLG_RT_DLSYM;
3179 
3180 	for (ALIST_TRAVERSE(alist, off, lmpp)) {
3181 		uint_t	cnt = 0;
3182 		Slookup	sl = *slp;
3183 		Dyninfo	*dip;
3184 
3185 		/*
3186 		 * Loop through the DT_NEEDED entries examining each object for
3187 		 * the symbol.  If the symbol is not found the object is in turn
3188 		 * added to the alist, so that its DT_NEEDED entires may be
3189 		 * examined.
3190 		 */
3191 		lmp = *lmpp;
3192 		for (dip = DYNINFO(lmp); cnt < DYNINFOCNT(lmp); cnt++, dip++) {
3193 			Rt_map *nlmp;
3194 
3195 			if (((dip->di_flags & FLG_DI_NEEDED) == 0) ||
3196 			    dip->di_info)
3197 				continue;
3198 
3199 			/*
3200 			 * If this entry defines a lazy dependency try loading
3201 			 * it.  If the file can't be loaded, consider this
3202 			 * non-fatal and continue the search (lazy loaded
3203 			 * dependencies need not exist and their loading should
3204 			 * only be fatal if called from a relocation).
3205 			 *
3206 			 * If the file is already loaded and relocated we must
3207 			 * still inspect it for symbols, even though it might
3208 			 * have already been searched.  This lazy load operation
3209 			 * might have promoted the permissions of the object,
3210 			 * and thus made the object applicable for this symbol
3211 			 * search, whereas before the object might have been
3212 			 * skipped.
3213 			 */
3214 			if ((nlmp = elf_lazy_load(lmp, cnt, name)) == 0)
3215 				continue;
3216 
3217 			/*
3218 			 * If this object isn't yet a part of the dynamic list
3219 			 * then inspect it for the symbol.  If the symbol isn't
3220 			 * found add the object to the dynamic list so that we
3221 			 * can inspect its dependencies.
3222 			 */
3223 			if (FLAGS(nlmp) & FLG_RT_DLSYM)
3224 				continue;
3225 
3226 			sl.sl_imap = nlmp;
3227 			if (sym = LM_LOOKUP_SYM(sl.sl_cmap)(&sl, _lmp, binfo))
3228 				break;
3229 
3230 			/*
3231 			 * Some dlsym() operations are already traversing a
3232 			 * link-map (dlopen(0)), and thus there's no need to
3233 			 * build our own dynamic dependency list.
3234 			 */
3235 			if ((sl.sl_flags & LKUP_NODESCENT) == 0) {
3236 				if (alist_append(&alist, &nlmp,
3237 				    sizeof (Rt_map *), AL_CNT_LAZYFIND) == 0) {
3238 					elf_lazy_cleanup(alist);
3239 					return (0);
3240 				}
3241 				FLAGS(nlmp) |= FLG_RT_DLSYM;
3242 			}
3243 		}
3244 		if (sym)
3245 			break;
3246 	}
3247 
3248 	elf_lazy_cleanup(alist);
3249 	return (sym);
3250 }
3251 
3252 /*
3253  * Warning message for bad r_offset.
3254  */
3255 void
3256 elf_reloc_bad(Rt_map *lmp, void *rel, uchar_t rtype, ulong_t roffset,
3257     ulong_t rsymndx)
3258 {
3259 	const char	*name = (char *)0;
3260 	Lm_list		*lml = LIST(lmp);
3261 	int		trace;
3262 
3263 	if ((lml->lm_flags & LML_FLG_TRC_ENABLE) &&
3264 	    (((rtld_flags & RT_FL_SILENCERR) == 0) ||
3265 	    (lml->lm_flags & LML_FLG_TRC_VERBOSE)))
3266 		trace = 1;
3267 	else
3268 		trace = 0;
3269 
3270 	if ((trace == 0) && (DBG_ENABLED == 0))
3271 		return;
3272 
3273 	if (rsymndx) {
3274 		Sym	*symref = (Sym *)((ulong_t)SYMTAB(lmp) +
3275 				(rsymndx * SYMENT(lmp)));
3276 
3277 		if (ELF_ST_BIND(symref->st_info) != STB_LOCAL)
3278 			name = (char *)(STRTAB(lmp) + symref->st_name);
3279 	}
3280 
3281 	if (name == 0)
3282 		name = MSG_ORIG(MSG_STR_EMPTY);
3283 
3284 	if (trace) {
3285 		const char *rstr;
3286 
3287 		rstr = _conv_reloc_type((uint_t)rtype);
3288 		(void) printf(MSG_INTL(MSG_LDD_REL_ERR1), rstr, name,
3289 		    EC_ADDR(roffset));
3290 		return;
3291 	}
3292 
3293 	Dbg_reloc_error(lml, ELF_DBG_RTLD, M_MACH, M_REL_SHT_TYPE, rel, name);
3294 }
3295 
3296 /*
3297  * Resolve a static TLS relocation.
3298  */
3299 long
3300 elf_static_tls(Rt_map *lmp, Sym *sym, void *rel, uchar_t rtype, char *name,
3301     ulong_t roffset, long value)
3302 {
3303 	Lm_list	*lml = LIST(lmp);
3304 
3305 	/*
3306 	 * Relocations against a static TLS block have limited support once
3307 	 * process initialization has completed.  Any error condition should be
3308 	 * discovered by testing for DF_STATIC_TLS as part of loading an object,
3309 	 * however individual relocations are tested in case the dynamic flag
3310 	 * had not been set when this object was built.
3311 	 */
3312 	if (PTTLS(lmp) == 0) {
3313 		DBG_CALL(Dbg_reloc_in(lml, ELF_DBG_RTLD, M_MACH,
3314 		    M_REL_SHT_TYPE, rel, NULL, name));
3315 		eprintf(lml, ERR_FATAL, MSG_INTL(MSG_REL_BADTLS),
3316 		    _conv_reloc_type((uint_t)rtype), NAME(lmp),
3317 		    name ? demangle(name) : MSG_INTL(MSG_STR_UNKNOWN));
3318 		return (0);
3319 	}
3320 
3321 	/*
3322 	 * If no static TLS has been set aside for this object, determine if
3323 	 * any can be obtained.  Enforce that any object using static TLS is
3324 	 * non-deletable.
3325 	 */
3326 	if (TLSSTATOFF(lmp) == 0) {
3327 		FLAGS1(lmp) |= FL1_RT_TLSSTAT;
3328 		MODE(lmp) |= RTLD_NODELETE;
3329 
3330 		if (tls_assign(lml, lmp, PTTLS(lmp)) == 0) {
3331 			DBG_CALL(Dbg_reloc_in(lml, ELF_DBG_RTLD, M_MACH,
3332 			    M_REL_SHT_TYPE, rel, NULL, name));
3333 			eprintf(lml, ERR_FATAL, MSG_INTL(MSG_REL_BADTLS),
3334 			    _conv_reloc_type((uint_t)rtype), NAME(lmp),
3335 			    name ? demangle(name) : MSG_INTL(MSG_STR_UNKNOWN));
3336 			return (0);
3337 		}
3338 	}
3339 
3340 	/*
3341 	 * Typically, a static TLS offset is maintained as a symbols value.
3342 	 * For local symbols that are not apart of the dynamic symbol table,
3343 	 * the TLS relocation points to a section symbol, and the static TLS
3344 	 * offset was deposited in the associated GOT table.  Make sure the GOT
3345 	 * is cleared, so that the value isn't reused in do_reloc().
3346 	 */
3347 	if (ELF_ST_BIND(sym->st_info) == STB_LOCAL) {
3348 		if ((ELF_ST_TYPE(sym->st_info) == STT_SECTION)) {
3349 			value = *(long *)roffset;
3350 			*(long *)roffset = 0;
3351 		} else {
3352 			value = sym->st_value;
3353 		}
3354 	}
3355 	return (-(TLSSTATOFF(lmp) - value));
3356 }
3357