resolve.c revision 1.70 
1/*	$OpenBSD: resolve.c,v 1.70 2016/01/24 03:45:54 guenther Exp $ */
2
3/*
4 * Copyright (c) 1998 Per Fogelstrom, Opsycon AB
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
16 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
17 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
19 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 *
27 */
28
29#define _DYN_LOADER
30
31#include <sys/types.h>
32
33#include <limits.h>
34#include <nlist.h>
35#include <link.h>
36#include "syscall.h"
37#include "archdep.h"
38#include "path.h"
39#include "resolve.h"
40#include "dl_prebind.h"
41
42/* substitution types */
43typedef enum {
44	SUBST_UNKNOWN, SUBST_ORIGIN, SUBST_OSNAME, SUBST_OSREL, SUBST_PLATFORM
45} SUBST_TYPES;
46
47elf_object_t *_dl_objects;
48elf_object_t *_dl_last_object;
49elf_object_t *_dl_loading_object;
50
51/*
52 * Add a new dynamic object to the object list.
53 */
54void
55_dl_add_object(elf_object_t *object)
56{
57	/*
58	 * If a .so is marked nodelete, then the entire load group that it's
59	 * in needs to be kept around forever, so add a reference there.
60	 * XXX It would be better if we tracked inter-object dependencies
61	 * from relocations and didn't leave dangling pointers when a load
62	 * group was partially unloaded.  That would render this unnecessary.
63	 */
64	if (object->obj_flags & DF_1_NODELETE &&
65	    (object->load_object->status & STAT_NODELETE) == 0) {
66		DL_DEB(("objname %s is nodelete\n", object->load_name));
67		object->load_object->opencount++;
68		object->load_object->status |= STAT_NODELETE;
69	}
70
71	/*
72	 * if this is a new object, prev will be NULL
73	 * != NULL if an object already in the list
74	 * prev == NULL for the first item in the list, but that will
75	 * be the executable.
76	 */
77	if (object->prev != NULL)
78		return;
79
80	if (_dl_objects == NULL) {			/* First object ? */
81		_dl_last_object = _dl_objects = object;
82	} else {
83		_dl_last_object->next = object;
84		object->prev = _dl_last_object;
85		_dl_last_object = object;
86	}
87}
88
89/*
90 * Identify substitution sequence name.
91 */
92static int
93_dl_subst_name(const char *name, size_t siz) {
94	switch (siz) {
95	case 5:
96		if (_dl_strncmp(name, "OSREL", 5) == 0)
97			return SUBST_OSREL;
98		break;
99	case 6:
100		if (_dl_strncmp(name, "ORIGIN", 6) == 0)
101			return SUBST_ORIGIN;
102		if (_dl_strncmp(name, "OSNAME", 6) == 0)
103			return SUBST_OSNAME;
104		break;
105	case 8:
106		if (_dl_strncmp(name, "PLATFORM", 8) == 0)
107			return SUBST_PLATFORM;
108		break;
109	}
110
111	return (SUBST_UNKNOWN);
112}
113
114/*
115 * Perform $ORIGIN substitutions on path
116 */
117static void
118_dl_origin_subst_path(elf_object_t *object, const char *origin_path,
119    char **path)
120{
121	char tmp_path[PATH_MAX];
122	char *new_path, *tp;
123	const char *pp, *name, *value;
124	static struct utsname uts;
125	size_t value_len;
126	int skip_brace;
127
128	if (uts.sysname[0] == '\0') {
129		if (_dl_uname(&uts) != 0)
130			return;
131	}
132
133	tp = tmp_path;
134	pp = *path;
135
136	while (*pp != '\0' && (tp - tmp_path) < sizeof(tmp_path)) {
137
138		/* copy over chars up to but not including $ */
139		while (*pp != '\0' && *pp != '$' &&
140		    (tp - tmp_path) < sizeof(tmp_path))
141			*tp++ = *pp++;
142
143		/* substitution sequence detected */
144		if (*pp == '$' && (tp - tmp_path) < sizeof(tmp_path)) {
145			pp++;
146
147			if ((skip_brace = (*pp == '{')))
148				pp++;
149
150			/* skip over name */
151			name = pp;
152			while (_dl_isalnum((unsigned char)*pp) || *pp == '_')
153				pp++;
154
155			switch (_dl_subst_name(name, pp - name)) {
156			case SUBST_ORIGIN:
157				value = origin_path;
158				break;
159			case SUBST_OSNAME:
160				value = uts.sysname;
161				break;
162			case SUBST_OSREL:
163				value = uts.release;
164				break;
165			case SUBST_PLATFORM:
166				value = uts.machine;
167				break;
168			default:
169				value = "";
170			}
171
172			value_len = _dl_strlen(value);
173			if (value_len >= sizeof(tmp_path) - (tp - tmp_path))
174				return;
175
176			_dl_bcopy(value, tp, value_len);
177			tp += value_len;
178
179			if (skip_brace && *pp == '}')
180				pp++;
181		}
182	}
183
184	/* no substitution made if result exceeds sizeof(tmp_path) */
185	if (tp - tmp_path >= sizeof(tmp_path))
186		return;
187
188	/* NULL terminate tmp_path */
189	*tp = '\0';
190
191	if (_dl_strcmp(tmp_path, *path) == 0)
192		return;
193
194	new_path = _dl_strdup(tmp_path);
195	if (new_path == NULL)
196		return;
197
198	DL_DEB(("orig_path %s\n", *path));
199	DL_DEB(("new_path  %s\n", new_path));
200
201	_dl_free(*path);
202	*path = new_path;
203}
204
205/*
206 * Determine origin_path from object load_name. The origin_path argument
207 * must refer to a buffer capable of storing at least PATH_MAX characters.
208 * Returns 0 on success.
209 */
210static int
211_dl_origin_path(elf_object_t *object, char *origin_path)
212{
213	const char *dirname_path = _dl_dirname(object->load_name);
214
215	if (dirname_path == NULL)
216		return -1;
217
218	if (_dl_realpath(dirname_path, origin_path) == NULL)
219		return -1;
220
221	return 0;
222}
223
224/*
225 * Perform $ORIGIN substitutions on rpath
226 */
227static void
228_dl_origin_subst(elf_object_t *object)
229{
230	char origin_path[PATH_MAX];
231	char **pp;
232
233	if (_dl_origin_path(object, origin_path) != 0)
234		return;
235
236	/* perform path substitutions on each segment of rpath */
237	for (pp = object->rpath; *pp != NULL; pp++) {
238		_dl_origin_subst_path(object, origin_path, pp);
239	}
240}
241
242/*
243 * Initialize a new dynamic object.
244 */
245elf_object_t *
246_dl_finalize_object(const char *objname, Elf_Dyn *dynp, Elf_Phdr *phdrp,
247    int phdrc, const int objtype, const long lbase, const long obase)
248{
249	elf_object_t *object;
250#if 0
251	_dl_printf("objname [%s], dynp %p, objtype %x lbase %lx, obase %lx\n",
252	    objname, dynp, objtype, lbase, obase);
253#endif
254	object = _dl_calloc(1, sizeof(elf_object_t));
255	if (object == NULL)
256		_dl_exit(7);
257	object->prev = object->next = NULL;
258
259	object->load_dyn = dynp;
260	while (dynp->d_tag != DT_NULL) {
261		if (dynp->d_tag < DT_NUM)
262			object->Dyn.info[dynp->d_tag] = dynp->d_un.d_val;
263		else if (dynp->d_tag >= DT_LOPROC &&
264		    dynp->d_tag < DT_LOPROC + DT_PROCNUM)
265			object->Dyn.info[dynp->d_tag + DT_NUM - DT_LOPROC] =
266			    dynp->d_un.d_val;
267		if (dynp->d_tag == DT_TEXTREL)
268			object->dyn.textrel = 1;
269		if (dynp->d_tag == DT_SYMBOLIC)
270			object->dyn.symbolic = 1;
271		if (dynp->d_tag == DT_BIND_NOW)
272			object->obj_flags |= DF_1_NOW;
273		if (dynp->d_tag == DT_FLAGS_1)
274			object->obj_flags |= dynp->d_un.d_val;
275		if (dynp->d_tag == DT_RELACOUNT)
276			object->relacount = dynp->d_un.d_val;
277		if (dynp->d_tag == DT_RELCOUNT)
278			object->relcount = dynp->d_un.d_val;
279		dynp++;
280	}
281	DL_DEB((" flags %s = 0x%x\n", objname, object->obj_flags ));
282	object->obj_type = objtype;
283
284	if (_dl_loading_object == NULL) {
285		/*
286		 * no loading object, object is the loading object,
287		 * as it is either executable, or dlopened()
288		 */
289		_dl_loading_object = object;
290	}
291
292	if ((object->obj_flags & DF_1_NOOPEN) != 0 &&
293	    _dl_loading_object->obj_type == OBJTYPE_DLO &&
294	    _dl_traceld == NULL) {
295		_dl_free(object);
296		_dl_errno = DL_CANT_LOAD_OBJ;
297		return(NULL);
298	}
299
300	/*
301	 *  Now relocate all pointer to dynamic info, but only
302	 *  the ones which have pointer values.
303	 */
304	if (object->Dyn.info[DT_PLTGOT])
305		object->Dyn.info[DT_PLTGOT] += obase;
306	if (object->Dyn.info[DT_HASH])
307		object->Dyn.info[DT_HASH] += obase;
308	if (object->Dyn.info[DT_STRTAB])
309		object->Dyn.info[DT_STRTAB] += obase;
310	if (object->Dyn.info[DT_SYMTAB])
311		object->Dyn.info[DT_SYMTAB] += obase;
312	if (object->Dyn.info[DT_RELA])
313		object->Dyn.info[DT_RELA] += obase;
314	if (object->Dyn.info[DT_SONAME])
315		object->Dyn.info[DT_SONAME] += object->Dyn.info[DT_STRTAB];
316	if (object->Dyn.info[DT_RPATH])
317		object->Dyn.info[DT_RPATH] += object->Dyn.info[DT_STRTAB];
318	if (object->Dyn.info[DT_REL])
319		object->Dyn.info[DT_REL] += obase;
320	if (object->Dyn.info[DT_INIT])
321		object->Dyn.info[DT_INIT] += obase;
322	if (object->Dyn.info[DT_FINI])
323		object->Dyn.info[DT_FINI] += obase;
324	if (object->Dyn.info[DT_JMPREL])
325		object->Dyn.info[DT_JMPREL] += obase;
326
327	if (object->Dyn.info[DT_HASH] != 0) {
328		Elf_Word *hashtab = (Elf_Word *)object->Dyn.info[DT_HASH];
329
330		object->nbuckets = hashtab[0];
331		object->nchains = hashtab[1];
332		object->buckets = hashtab + 2;
333		object->chains = object->buckets + object->nbuckets;
334	}
335
336	object->phdrp = phdrp;
337	object->phdrc = phdrc;
338	object->load_base = lbase;
339	object->obj_base = obase;
340	object->load_name = _dl_strdup(objname);
341	if (object->load_name == NULL)
342		_dl_exit(7);
343	object->load_object = _dl_loading_object;
344	if (object->load_object == object)
345		DL_DEB(("head %s\n", object->load_name));
346	DL_DEB(("obj %s has %s as head\n", object->load_name,
347	    _dl_loading_object->load_name ));
348	object->refcount = 0;
349	TAILQ_INIT(&object->child_list);
350	object->opencount = 0;	/* # dlopen() & exe */
351	object->grprefcount = 0;
352	/* default dev, inode for dlopen-able objects. */
353	object->dev = 0;
354	object->inode = 0;
355	object->lastlookup = 0;
356	TAILQ_INIT(&object->grpsym_list);
357	TAILQ_INIT(&object->grpref_list);
358
359	if (object->dyn.rpath) {
360		object->rpath = _dl_split_path(object->dyn.rpath);
361		if ((object->obj_flags & DF_1_ORIGIN) && _dl_trust)
362			_dl_origin_subst(object);
363	}
364
365	_dl_trace_object_setup(object);
366
367	return (object);
368}
369
370static void
371_dl_tailq_free(struct dep_node *n)
372{
373	struct dep_node *next;
374
375	while (n != NULL) {
376		next = TAILQ_NEXT(n, next_sib);
377		_dl_free(n);
378		n = next;
379	}
380}
381
382elf_object_t *free_objects;
383
384void
385_dl_cleanup_objects()
386{
387	elf_object_t *nobj, *head;
388	struct dep_node *n, *next;
389
390	n = TAILQ_FIRST(&_dlopened_child_list);
391	while (n != NULL) {
392		next = TAILQ_NEXT(n, next_sib);
393		if (OBJECT_DLREF_CNT(n->data) == 0) {
394			TAILQ_REMOVE(&_dlopened_child_list, n, next_sib);
395			_dl_free(n);
396		}
397		n = next;
398	}
399
400	head = free_objects;
401	free_objects = NULL;
402	while (head != NULL) {
403		if (head->load_name)
404			_dl_free(head->load_name);
405		if (head->sod.sod_name)
406			_dl_free((char *)head->sod.sod_name);
407		if (head->rpath)
408			_dl_free_path(head->rpath);
409		_dl_tailq_free(TAILQ_FIRST(&head->grpsym_list));
410		_dl_tailq_free(TAILQ_FIRST(&head->child_list));
411		_dl_tailq_free(TAILQ_FIRST(&head->grpref_list));
412		nobj = head->next;
413		_dl_free(head);
414		head = nobj;
415	}
416}
417
418void
419_dl_remove_object(elf_object_t *object)
420{
421	object->prev->next = object->next;
422	if (object->next)
423		object->next->prev = object->prev;
424
425	if (_dl_last_object == object)
426		_dl_last_object = object->prev;
427
428	object->next = free_objects;
429	free_objects = object;
430}
431
432/*
433 * mprotect a segment to the indicated protection.  If 'addr' is non-zero,
434 * then it's the start address, else the value of 'start_sym' is the start.
435 * The value of 'end_sym' is the end address.  The start is rounded down
436 * and the end is rounded up to page boundaries.  Returns 'addr' or the
437 * address of the start symbol.
438 */
439void *
440_dl_protect_segment(elf_object_t *object, Elf_Addr addr,
441    const char *start_sym, const char *end_sym, int prot)
442{
443	const Elf_Sym *this;
444	Elf_Addr ooff, start, end;
445
446	if (addr == 0) {
447		this = NULL;
448		ooff = _dl_find_symbol(start_sym, &this,
449		    SYM_SEARCH_OBJ | SYM_NOWARNNOTFOUND | SYM_PLT, NULL,
450		    object, NULL);
451		/* If not found, nothing to do */
452		if (this == NULL)
453			return (NULL);
454		addr = ooff + this->st_value;
455	}
456
457	this = NULL;
458	ooff = _dl_find_symbol(end_sym, &this,
459	    SYM_SEARCH_OBJ | SYM_NOWARNNOTFOUND | SYM_PLT, NULL, object, NULL);
460	if (this == NULL)
461		addr = 0;
462	else {
463		end = ooff + this->st_value;
464		if (addr < end) {
465			start = ELF_TRUNC(addr, _dl_pagesz);
466			end = ELF_ROUND(end, _dl_pagesz);
467			_dl_mprotect((void *)start, end - start, prot);
468		}
469	}
470
471	return ((void *)addr);
472}
473
474
475sym_cache *_dl_symcache;
476int _dl_symcachestat_hits;
477int _dl_symcachestat_lookups;
478
479
480Elf_Addr
481_dl_find_symbol_bysym(elf_object_t *req_obj, unsigned int symidx,
482    const Elf_Sym **this, int flags, const Elf_Sym *ref_sym, const elf_object_t **pobj)
483{
484	Elf_Addr ret;
485	const Elf_Sym *sym;
486	const char *symn;
487	const elf_object_t *sobj;
488
489	_dl_symcachestat_lookups ++;
490	if (_dl_symcache != NULL &&
491	    symidx < req_obj->nchains &&
492	    _dl_symcache[symidx].obj != NULL &&
493	    _dl_symcache[symidx].sym != NULL &&
494	    _dl_symcache[symidx].flags == flags) {
495
496		_dl_symcachestat_hits++;
497		sobj = _dl_symcache[symidx].obj;
498		*this = _dl_symcache[symidx].sym;
499		if (pobj)
500			*pobj = sobj;
501		if (_dl_prebind_validate) /* XXX */
502			prebind_validate(req_obj, symidx, flags, ref_sym);
503		return sobj->obj_base;
504	}
505
506	sym = req_obj->dyn.symtab;
507	sym += symidx;
508	symn = req_obj->dyn.strtab + sym->st_name;
509
510	ret = _dl_find_symbol(symn, this, flags, ref_sym, req_obj, &sobj);
511
512	if (pobj)
513		*pobj = sobj;
514
515	if (_dl_symcache != NULL && symidx < req_obj->nchains) {
516#if 0
517		DL_DEB(("cache miss %d %p %p, %p %p %s %s %d %d %s\n",
518		    symidx,
519		    _dl_symcache[symidx].sym, *this,
520		    _dl_symcache[symidx].obj, sobj, sobj->load_name,
521		    sobj->dyn.strtab + (*this)->st_name,
522		    _dl_symcache[symidx].flags, flags, req_obj->load_name));
523#endif
524
525		_dl_symcache[symidx].sym = *this;
526		_dl_symcache[symidx].obj = sobj;
527		_dl_symcache[symidx].flags = flags;
528	}
529
530	return ret;
531}
532
533int _dl_searchnum = 0;
534void
535_dl_newsymsearch(void)
536{
537	_dl_searchnum += 1;
538
539	if (_dl_searchnum < 0) {
540		/*
541		 * If the signed number rolls over, reset all counters so
542		 * we dont get accidental collision.
543		 */
544		elf_object_t *walkobj;
545		for (walkobj = _dl_objects;
546		    walkobj != NULL;
547		    walkobj = walkobj->next) {
548			walkobj->lastlookup = 0;
549		}
550		_dl_searchnum = 1;
551	}
552}
553
554static int
555_dl_find_symbol_obj(elf_object_t *object, const char *name, unsigned long hash,
556    int flags, const Elf_Sym **this, const Elf_Sym **weak_sym,
557    elf_object_t **weak_object)
558{
559	const Elf_Sym	*symt = object->dyn.symtab;
560	const char	*strt = object->dyn.strtab;
561	long	si;
562	const char *symn;
563
564	for (si = object->buckets[hash % object->nbuckets];
565	    si != STN_UNDEF; si = object->chains[si]) {
566		const Elf_Sym *sym = symt + si;
567
568		if (sym->st_value == 0)
569			continue;
570
571		if (ELF_ST_TYPE(sym->st_info) != STT_NOTYPE &&
572		    ELF_ST_TYPE(sym->st_info) != STT_OBJECT &&
573		    ELF_ST_TYPE(sym->st_info) != STT_FUNC)
574			continue;
575
576		symn = strt + sym->st_name;
577		if (sym != *this && _dl_strcmp(symn, name))
578			continue;
579
580		/* allow this symbol if we are referring to a function
581		 * which has a value, even if section is UNDEF.
582		 * this allows &func to refer to PLT as per the
583		 * ELF spec. st_value is checked above.
584		 * if flags has SYM_PLT set, we must have actual
585		 * symbol, so this symbol is skipped.
586		 */
587		if (sym->st_shndx == SHN_UNDEF) {
588			if ((flags & SYM_PLT) || sym->st_value == 0 ||
589			    ELF_ST_TYPE(sym->st_info) != STT_FUNC)
590				continue;
591		}
592
593		if (ELF_ST_BIND(sym->st_info) == STB_GLOBAL) {
594			*this = sym;
595			return 1;
596		} else if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
597			if (!*weak_sym) {
598				*weak_sym = sym;
599				*weak_object = object;
600			}
601		}
602	}
603	return 0;
604}
605
606Elf_Addr
607_dl_find_symbol(const char *name, const Elf_Sym **this,
608    int flags, const Elf_Sym *ref_sym, elf_object_t *req_obj,
609    const elf_object_t **pobj)
610{
611	const Elf_Sym *weak_sym = NULL;
612	unsigned long h = 0;
613	const char *p = name;
614	elf_object_t *object = NULL, *weak_object = NULL;
615	int found = 0;
616	struct dep_node *n, *m;
617
618
619	while (*p) {
620		unsigned long g;
621		h = (h << 4) + *p++;
622		if ((g = h & 0xf0000000))
623			h ^= g >> 24;
624		h &= ~g;
625	}
626
627	if (req_obj->dyn.symbolic)
628		if (_dl_find_symbol_obj(req_obj, name, h, flags, this, &weak_sym,
629		    &weak_object)) {
630			object = req_obj;
631			found = 1;
632			goto found;
633		}
634
635	if (flags & SYM_SEARCH_OBJ) {
636		if (_dl_find_symbol_obj(req_obj, name, h, flags, this,
637		    &weak_sym, &weak_object)) {
638			object = req_obj;
639			found = 1;
640		}
641	} else if (flags & SYM_DLSYM) {
642		if (_dl_find_symbol_obj(req_obj, name, h, flags, this,
643		    &weak_sym, &weak_object)) {
644			object = req_obj;
645			found = 1;
646		}
647		if (weak_object != NULL && found == 0) {
648			object=weak_object;
649			*this = weak_sym;
650			found = 1;
651		}
652		/* search dlopened obj and all children */
653
654		if (found == 0) {
655			TAILQ_FOREACH(n, &req_obj->load_object->grpsym_list,
656			    next_sib) {
657				if (_dl_find_symbol_obj(n->data, name, h,
658				    flags, this,
659				    &weak_sym, &weak_object)) {
660					object = n->data;
661					found = 1;
662					break;
663				}
664			}
665		}
666	} else {
667		int skip = 0;
668
669		if ((flags & SYM_SEARCH_SELF) || (flags & SYM_SEARCH_NEXT))
670			skip = 1;
671
672		_dl_newsymsearch();
673
674		/*
675		 * search dlopened objects: global or req_obj == dlopened_obj
676		 * and and it's children
677		 */
678		TAILQ_FOREACH(n, &_dlopened_child_list, next_sib) {
679			if (((n->data->obj_flags & DF_1_GLOBAL) == 0) &&
680			    (n->data != req_obj->load_object))
681				continue;
682
683			n->data->lastlookup_head = _dl_searchnum;
684			TAILQ_FOREACH(m, &n->data->grpsym_list, next_sib) {
685				if (skip == 1) {
686					if (m->data == req_obj) {
687						skip = 0;
688						if (flags & SYM_SEARCH_NEXT)
689							continue;
690					} else
691						continue;
692				}
693				if ((flags & SYM_SEARCH_OTHER) &&
694				    (m->data == req_obj))
695					continue;
696				m->data->lastlookup = _dl_searchnum;
697				if (_dl_find_symbol_obj(m->data, name, h, flags,
698				    this, &weak_sym, &weak_object)) {
699					object = m->data;
700					found = 1;
701					goto found;
702				}
703			}
704		}
705	}
706
707found:
708	if (weak_object != NULL && found == 0) {
709		object=weak_object;
710		*this = weak_sym;
711		found = 1;
712	}
713
714
715	if (found == 0) {
716		if ((ref_sym == NULL ||
717		    (ELF_ST_BIND(ref_sym->st_info) != STB_WEAK)) &&
718		    (flags & SYM_WARNNOTFOUND))
719			_dl_printf("%s:%s: undefined symbol '%s'\n",
720			    _dl_progname, req_obj->load_name, name);
721		return (0);
722	}
723
724	if (ref_sym != NULL && ref_sym->st_size != 0 &&
725	    (ref_sym->st_size != (*this)->st_size)  &&
726	    (ELF_ST_TYPE((*this)->st_info) != STT_FUNC) ) {
727		_dl_printf("%s:%s: %s : WARNING: "
728		    "symbol(%s) size mismatch, relink your program\n",
729		    _dl_progname, req_obj->load_name,
730		    object->load_name, name);
731	}
732
733	if (pobj)
734		*pobj = object;
735
736	return (object->obj_base);
737}
738
739void
740_dl_debug_state(void)
741{
742	/* Debugger stub */
743}
744