resolve.c revision 1.96
1/*	$OpenBSD: resolve.c,v 1.96 2021/11/12 22:28:13 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
41/* substitution types */
42typedef enum {
43	SUBST_UNKNOWN, SUBST_ORIGIN, SUBST_OSNAME, SUBST_OSREL, SUBST_PLATFORM
44} SUBST_TYPES;
45
46struct symlookup {
47	const char		*sl_name;
48	struct sym_res		sl_out;
49	struct sym_res		sl_weak_out;
50	unsigned long		sl_elf_hash;
51	uint32_t		sl_gnu_hash;
52	int			sl_flags;
53};
54
55elf_object_t *_dl_objects;
56int object_count;
57static elf_object_t *_dl_last_object;
58elf_object_t *_dl_loading_object;
59
60void
61_dl_handle_nodelete(elf_object_t *object)
62{
63	/*
64	 * If a .so is marked nodelete, then the entire load group that it's
65	 * in needs to be kept around forever, so add a reference there.
66	 * XXX It would be better if we tracked inter-object dependencies
67	 * from relocations and didn't leave dangling pointers when a load
68	 * group was partially unloaded.  That would render this unnecessary.
69	 */
70	if (object->obj_flags & DF_1_NODELETE &&
71	    (object->load_object->status & STAT_NODELETE) == 0) {
72		DL_DEB(("objname %s is nodelete\n", object->load_name));
73		object->load_object->opencount++;
74		object->load_object->status |= STAT_NODELETE;
75	}
76}
77
78/*
79 * Add a new dynamic object to the object list.
80 */
81void
82_dl_add_object(elf_object_t *object)
83{
84	_dl_handle_nodelete(object);
85
86	/*
87	 * if this is a new object, prev will be NULL
88	 * != NULL if an object already in the list
89	 * prev == NULL for the first item in the list, but that will
90	 * be the executable.
91	 */
92	if (object->prev != NULL)
93		return;
94
95	if (_dl_objects == NULL) {			/* First object ? */
96		_dl_last_object = _dl_objects = object;
97		object_count = 2;			/* count ld.so early */
98	} else {
99		_dl_last_object->next = object;
100		object->prev = _dl_last_object;
101		_dl_last_object = object;
102		if (object->obj_type != OBJTYPE_LDR)	/* see above */
103			object_count++;
104	}
105}
106
107/*
108 * Identify substitution sequence name.
109 */
110static int
111_dl_subst_name(const char *name, size_t siz) {
112	switch (siz) {
113	case 5:
114		if (_dl_strncmp(name, "OSREL", 5) == 0)
115			return SUBST_OSREL;
116		break;
117	case 6:
118		if (_dl_strncmp(name, "ORIGIN", 6) == 0)
119			return SUBST_ORIGIN;
120		if (_dl_strncmp(name, "OSNAME", 6) == 0)
121			return SUBST_OSNAME;
122		break;
123	case 8:
124		if (_dl_strncmp(name, "PLATFORM", 8) == 0)
125			return SUBST_PLATFORM;
126		break;
127	}
128
129	return (SUBST_UNKNOWN);
130}
131
132/*
133 * Perform $ORIGIN substitutions on path
134 */
135static void
136_dl_origin_subst_path(elf_object_t *object, const char *origin_path,
137    char **path)
138{
139	char tmp_path[PATH_MAX];
140	char *new_path, *tp;
141	const char *pp, *name, *value;
142	static struct utsname uts;
143	size_t value_len;
144	int skip_brace;
145
146	if (uts.sysname[0] == '\0') {
147		if (_dl_uname(&uts) != 0)
148			return;
149	}
150
151	tp = tmp_path;
152	pp = *path;
153
154	while (*pp != '\0' && (tp - tmp_path) < sizeof(tmp_path)) {
155
156		/* copy over chars up to but not including $ */
157		while (*pp != '\0' && *pp != '$' &&
158		    (tp - tmp_path) < sizeof(tmp_path))
159			*tp++ = *pp++;
160
161		/* substitution sequence detected */
162		if (*pp == '$' && (tp - tmp_path) < sizeof(tmp_path)) {
163			pp++;
164
165			if ((skip_brace = (*pp == '{')))
166				pp++;
167
168			/* skip over name */
169			name = pp;
170			while (_dl_isalnum((unsigned char)*pp) || *pp == '_')
171				pp++;
172
173			switch (_dl_subst_name(name, pp - name)) {
174			case SUBST_ORIGIN:
175				value = origin_path;
176				break;
177			case SUBST_OSNAME:
178				value = uts.sysname;
179				break;
180			case SUBST_OSREL:
181				value = uts.release;
182				break;
183			case SUBST_PLATFORM:
184				value = uts.machine;
185				break;
186			default:
187				value = "";
188			}
189
190			value_len = _dl_strlen(value);
191			if (value_len >= sizeof(tmp_path) - (tp - tmp_path))
192				return;
193
194			_dl_bcopy(value, tp, value_len);
195			tp += value_len;
196
197			if (skip_brace && *pp == '}')
198				pp++;
199		}
200	}
201
202	/* no substitution made if result exceeds sizeof(tmp_path) */
203	if (tp - tmp_path >= sizeof(tmp_path))
204		return;
205
206	/* NULL terminate tmp_path */
207	*tp = '\0';
208
209	if (_dl_strcmp(tmp_path, *path) == 0)
210		return;
211
212	new_path = _dl_strdup(tmp_path);
213	if (new_path == NULL)
214		return;
215
216	DL_DEB(("orig_path %s\n", *path));
217	DL_DEB(("new_path  %s\n", new_path));
218
219	_dl_free(*path);
220	*path = new_path;
221}
222
223/*
224 * Determine origin_path from object load_name. The origin_path argument
225 * must refer to a buffer capable of storing at least PATH_MAX characters.
226 * Returns 0 on success.
227 */
228static int
229_dl_origin_path(elf_object_t *object, char *origin_path)
230{
231	const char *dirname_path = _dl_dirname(object->load_name);
232
233	if (dirname_path == NULL)
234		return -1;
235
236	/* syscall in ld.so returns 0/-errno, where libc returns char* */
237	if (_dl___realpath(dirname_path, origin_path) < 0)
238		return -1;
239
240	return 0;
241}
242
243/*
244 * Perform $ORIGIN substitutions on runpath and rpath
245 */
246static void
247_dl_origin_subst(elf_object_t *object)
248{
249	char origin_path[PATH_MAX];
250	char **pp;
251
252	if (_dl_origin_path(object, origin_path) != 0)
253		return;
254
255	/* perform path substitutions on each segment of runpath and rpath */
256	if (object->runpath != NULL) {
257		for (pp = object->runpath; *pp != NULL; pp++)
258			_dl_origin_subst_path(object, origin_path, pp);
259	}
260	if (object->rpath != NULL) {
261		for (pp = object->rpath; *pp != NULL; pp++)
262			_dl_origin_subst_path(object, origin_path, pp);
263	}
264}
265
266/*
267 * Initialize a new dynamic object.
268 */
269elf_object_t *
270_dl_finalize_object(const char *objname, Elf_Dyn *dynp, Elf_Phdr *phdrp,
271    int phdrc, const int objtype, const long lbase, const long obase)
272{
273	elf_object_t *object;
274	Elf_Addr gnu_hash = 0;
275
276#if 0
277	_dl_printf("objname [%s], dynp %p, objtype %x lbase %lx, obase %lx\n",
278	    objname, dynp, objtype, lbase, obase);
279#endif
280	object = _dl_calloc(1, sizeof(elf_object_t));
281	if (object == NULL)
282		_dl_oom();
283	object->prev = object->next = NULL;
284
285	object->load_dyn = dynp;
286	while (dynp->d_tag != DT_NULL) {
287		if (dynp->d_tag < DT_NUM)
288			object->Dyn.info[dynp->d_tag] = dynp->d_un.d_val;
289		else if (dynp->d_tag >= DT_LOPROC &&
290		    dynp->d_tag < DT_LOPROC + DT_PROCNUM)
291			object->Dyn.info[dynp->d_tag + DT_NUM - DT_LOPROC] =
292			    dynp->d_un.d_val;
293		if (dynp->d_tag == DT_TEXTREL)
294			object->dyn.textrel = 1;
295		if (dynp->d_tag == DT_SYMBOLIC)
296			object->dyn.symbolic = 1;
297		if (dynp->d_tag == DT_BIND_NOW)
298			object->obj_flags |= DF_1_NOW;
299		if (dynp->d_tag == DT_FLAGS_1)
300			object->obj_flags |= dynp->d_un.d_val;
301		if (dynp->d_tag == DT_FLAGS) {
302			object->dyn.flags |= dynp->d_un.d_val;
303			if (dynp->d_un.d_val & DF_SYMBOLIC)
304				object->dyn.symbolic = 1;
305			if (dynp->d_un.d_val & DF_TEXTREL)
306				object->dyn.textrel = 1;
307			if (dynp->d_un.d_val & DF_ORIGIN)
308				object->obj_flags |= DF_1_ORIGIN;
309			if (dynp->d_un.d_val & DF_BIND_NOW)
310				object->obj_flags |= DF_1_NOW;
311		}
312		if (dynp->d_tag == DT_RELACOUNT)
313			object->relacount = dynp->d_un.d_val;
314		if (dynp->d_tag == DT_RELCOUNT)
315			object->relcount = dynp->d_un.d_val;
316		if (dynp->d_tag == DT_GNU_HASH)
317			gnu_hash = dynp->d_un.d_val;
318		dynp++;
319	}
320	DL_DEB((" flags %s = 0x%x\n", objname, object->obj_flags ));
321	object->obj_type = objtype;
322
323	if (_dl_loading_object == NULL) {
324		/*
325		 * no loading object, object is the loading object,
326		 * as it is either executable, or dlopened()
327		 */
328		_dl_loading_object = object;
329	}
330
331	if ((object->obj_flags & DF_1_NOOPEN) != 0 &&
332	    _dl_loading_object->obj_type == OBJTYPE_DLO &&
333	    !_dl_traceld) {
334		_dl_free(object);
335		_dl_errno = DL_CANT_LOAD_OBJ;
336		return(NULL);
337	}
338
339	/*
340	 *  Now relocate all pointer to dynamic info, but only
341	 *  the ones which have pointer values.
342	 */
343	if (object->Dyn.info[DT_PLTGOT])
344		object->Dyn.info[DT_PLTGOT] += obase;
345	if (object->Dyn.info[DT_STRTAB])
346		object->Dyn.info[DT_STRTAB] += obase;
347	if (object->Dyn.info[DT_SYMTAB])
348		object->Dyn.info[DT_SYMTAB] += obase;
349	if (object->Dyn.info[DT_RELA])
350		object->Dyn.info[DT_RELA] += obase;
351	if (object->Dyn.info[DT_SONAME])
352		object->Dyn.info[DT_SONAME] += object->Dyn.info[DT_STRTAB];
353	if (object->Dyn.info[DT_RPATH])
354		object->Dyn.info[DT_RPATH] += object->Dyn.info[DT_STRTAB];
355	if (object->Dyn.info[DT_RUNPATH])
356		object->Dyn.info[DT_RUNPATH] += object->Dyn.info[DT_STRTAB];
357	if (object->Dyn.info[DT_REL])
358		object->Dyn.info[DT_REL] += obase;
359	if (object->Dyn.info[DT_INIT])
360		object->Dyn.info[DT_INIT] += obase;
361	if (object->Dyn.info[DT_FINI])
362		object->Dyn.info[DT_FINI] += obase;
363	if (object->Dyn.info[DT_JMPREL])
364		object->Dyn.info[DT_JMPREL] += obase;
365	if (object->Dyn.info[DT_INIT_ARRAY])
366		object->Dyn.info[DT_INIT_ARRAY] += obase;
367	if (object->Dyn.info[DT_FINI_ARRAY])
368		object->Dyn.info[DT_FINI_ARRAY] += obase;
369	if (object->Dyn.info[DT_PREINIT_ARRAY])
370		object->Dyn.info[DT_PREINIT_ARRAY] += obase;
371	if (object->Dyn.info[DT_RELR])
372		object->Dyn.info[DT_RELR] += obase;
373
374	if (gnu_hash) {
375		Elf_Word *hashtab = (Elf_Word *)(gnu_hash + obase);
376		Elf_Word nbuckets = hashtab[0];
377		Elf_Word nmaskwords = hashtab[2];
378
379		/* validity check */
380		if (nbuckets > 0 && (nmaskwords & (nmaskwords - 1)) == 0) {
381			Elf_Word symndx = hashtab[1];
382			int bloom_size32 = (ELFSIZE / 32) * nmaskwords;
383
384			object->nbuckets = nbuckets;
385			object->symndx_gnu = symndx;
386			object->mask_bm_gnu = nmaskwords - 1;
387			object->shift2_gnu = hashtab[3];
388			object->bloom_gnu = (Elf_Addr *)(hashtab + 4);
389			object->buckets_gnu = hashtab + 4 + bloom_size32;
390			object->chains_gnu = object->buckets_gnu + nbuckets
391			    - symndx;
392
393			/*
394			 * If the ELF hash is present, get the total symbol
395			 * count ("nchains") from there.  Otherwise, count
396			 * the entries in the GNU hash chain.
397			 */
398			if (object->Dyn.info[DT_HASH] == 0) {
399				Elf_Word n;
400
401				for (n = 0; n < nbuckets; n++) {
402					Elf_Word bkt = object->buckets_gnu[n];
403					const Elf_Word *hashval;
404					if (bkt == 0)
405						continue;
406					hashval = &object->chains_gnu[bkt];
407					do {
408						symndx++;
409					} while ((*hashval++ & 1U) == 0);
410				}
411				object->nchains = symndx;
412			}
413			object->status |= STAT_GNU_HASH;
414		}
415	}
416	if (object->Dyn.info[DT_HASH] != 0) {
417		Elf_Hash_Word *hashtab =
418		    (Elf_Hash_Word *)(object->Dyn.info[DT_HASH] + obase);
419
420		object->nchains = hashtab[1];
421		if (object->nbuckets == 0) {
422			object->nbuckets = hashtab[0];
423			object->buckets_elf = hashtab + 2;
424			object->chains_elf = object->buckets_elf +
425			    object->nbuckets;
426		}
427	}
428
429	object->phdrp = phdrp;
430	object->phdrc = phdrc;
431	object->load_base = lbase;
432	object->obj_base = obase;
433	object->load_name = _dl_strdup(objname);
434	if (object->load_name == NULL)
435		_dl_oom();
436	object->load_object = _dl_loading_object;
437	if (object->load_object == object)
438		DL_DEB(("head %s\n", object->load_name));
439	DL_DEB(("obj %s has %s as head\n", object->load_name,
440	    _dl_loading_object->load_name ));
441	object->refcount = 0;
442	object->opencount = 0;	/* # dlopen() & exe */
443	object->grprefcount = 0;
444	/* default dev, inode for dlopen-able objects. */
445	object->dev = 0;
446	object->inode = 0;
447	object->grpsym_gen = 0;
448	TAILQ_INIT(&object->grpref_list);
449
450	if (object->dyn.runpath)
451		object->runpath = _dl_split_path(object->dyn.runpath);
452	/*
453	 * DT_RPATH is ignored if DT_RUNPATH is present...except in
454	 * the exe, whose DT_RPATH is a fallback for libs that don't
455	 * use DT_RUNPATH
456	 */
457	if (object->dyn.rpath && (object->runpath == NULL ||
458	    objtype == OBJTYPE_EXE))
459		object->rpath = _dl_split_path(object->dyn.rpath);
460	if ((object->obj_flags & DF_1_ORIGIN) && _dl_trust)
461		_dl_origin_subst(object);
462
463	_dl_trace_object_setup(object);
464
465	return (object);
466}
467
468static void
469_dl_tailq_free(struct dep_node *n)
470{
471	struct dep_node *next;
472
473	while (n != NULL) {
474		next = TAILQ_NEXT(n, next_sib);
475		_dl_free(n);
476		n = next;
477	}
478}
479
480static elf_object_t *free_objects;
481
482void
483_dl_cleanup_objects()
484{
485	elf_object_t *nobj, *head;
486	struct dep_node *n, *next;
487
488	n = TAILQ_FIRST(&_dlopened_child_list);
489	while (n != NULL) {
490		next = TAILQ_NEXT(n, next_sib);
491		if (OBJECT_DLREF_CNT(n->data) == 0) {
492			TAILQ_REMOVE(&_dlopened_child_list, n, next_sib);
493			_dl_free(n);
494		}
495		n = next;
496	}
497
498	head = free_objects;
499	free_objects = NULL;
500	while (head != NULL) {
501		_dl_free(head->load_name);
502		_dl_free((char *)head->sod.sod_name);
503		_dl_free_path(head->runpath);
504		_dl_free_path(head->rpath);
505		_dl_free(head->grpsym_vec.vec);
506		_dl_free(head->child_vec.vec);
507		_dl_tailq_free(TAILQ_FIRST(&head->grpref_list));
508		nobj = head->next;
509		_dl_free(head);
510		head = nobj;
511	}
512}
513
514void
515_dl_remove_object(elf_object_t *object)
516{
517	object->prev->next = object->next;
518	if (object->next)
519		object->next->prev = object->prev;
520
521	if (_dl_last_object == object)
522		_dl_last_object = object->prev;
523	object_count--;
524
525	object->next = free_objects;
526	free_objects = object;
527}
528
529static int
530matched_symbol(elf_object_t *obj, const Elf_Sym *sym, struct symlookup *sl)
531{
532	switch (ELF_ST_TYPE(sym->st_info)) {
533	case STT_FUNC:
534		/*
535		 * Allow this symbol if we are referring to a function which
536		 * has a value, even if section is UNDEF.  This allows &func
537		 * to refer to PLT as per the ELF spec.  If flags has SYM_PLT
538		 * set, we must have actual symbol, so this symbol is skipped.
539		 */
540		if ((sl->sl_flags & SYM_PLT) && sym->st_shndx == SHN_UNDEF)
541			return 0;
542		if (sym->st_value == 0)
543			return 0;
544		break;
545	case STT_NOTYPE:
546	case STT_OBJECT:
547		if (sym->st_value == 0)
548			return 0;
549#if 0
550		/* FALLTHROUGH */
551	case STT_TLS:
552#endif
553		if (sym->st_shndx == SHN_UNDEF)
554			return 0;
555		break;
556	default:
557		return 0;
558	}
559
560	if (sym != sl->sl_out.sym &&
561	    _dl_strcmp(sl->sl_name, obj->dyn.strtab + sym->st_name))
562		return 0;
563
564	if (ELF_ST_BIND(sym->st_info) == STB_GLOBAL) {
565		sl->sl_out.sym = sym;
566		sl->sl_out.obj = obj;
567		return 1;
568	} else if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
569		if (sl->sl_weak_out.sym == NULL) {
570			sl->sl_weak_out.sym = sym;
571			sl->sl_weak_out.obj = obj;
572		}
573		/* done with this object, but need to check other objects */
574		return -1;
575	}
576	return 0;
577}
578
579static int
580_dl_find_symbol_obj(elf_object_t *obj, struct symlookup *sl)
581{
582	const Elf_Sym	*symt = obj->dyn.symtab;
583
584	if (obj->status & STAT_GNU_HASH) {
585		uint32_t hash = sl->sl_gnu_hash;
586		Elf_Addr bloom_word;
587		unsigned int h1;
588		unsigned int h2;
589		Elf_Word bucket;
590		const Elf_Word *hashval;
591
592		/* pick right bitmask word from Bloom filter array */
593		bloom_word = obj->bloom_gnu[(hash / ELFSIZE) &
594		    obj->mask_bm_gnu];
595
596		/* calculate modulus ELFSIZE of gnu hash and its derivative */
597		h1 = hash & (ELFSIZE - 1);
598		h2 = (hash >> obj->shift2_gnu) & (ELFSIZE - 1);
599
600		/* Filter out the "definitely not in set" queries */
601		if (((bloom_word >> h1) & (bloom_word >> h2) & 1) == 0)
602			return 0;
603
604		/* Locate hash chain and corresponding value element */
605		bucket = obj->buckets_gnu[hash % obj->nbuckets];
606		if (bucket == 0)
607			return 0;
608		hashval = &obj->chains_gnu[bucket];
609		do {
610			if (((*hashval ^ hash) >> 1) == 0) {
611				const Elf_Sym *sym = symt +
612				    (hashval - obj->chains_gnu);
613
614				int r = matched_symbol(obj, sym, sl);
615				if (r)
616					return r > 0;
617			}
618		} while ((*hashval++ & 1U) == 0);
619	} else {
620		Elf_Word si;
621
622		for (si = obj->buckets_elf[sl->sl_elf_hash % obj->nbuckets];
623		    si != STN_UNDEF; si = obj->chains_elf[si]) {
624			const Elf_Sym *sym = symt + si;
625
626			int r = matched_symbol(obj, sym, sl);
627			if (r)
628				return r > 0;
629		}
630	}
631	return 0;
632}
633
634struct sym_res
635_dl_find_symbol(const char *name, int flags, const Elf_Sym *ref_sym,
636    elf_object_t *req_obj)
637{
638	const unsigned char *p;
639	unsigned char c;
640	struct symlookup sl = {
641		.sl_name = name,
642		.sl_out = { .sym = NULL },
643		.sl_weak_out = { .sym = NULL },
644		.sl_elf_hash = 0,
645		.sl_gnu_hash = 5381,
646		.sl_flags = flags,
647	};
648
649	/* Calculate both hashes in one pass */
650	for (p = (const unsigned char *)name; (c = *p) != '\0'; p++) {
651		unsigned long g;
652		sl.sl_elf_hash = (sl.sl_elf_hash << 4) + c;
653		if ((g = sl.sl_elf_hash & 0xf0000000))
654			sl.sl_elf_hash ^= g >> 24;
655		sl.sl_elf_hash &= ~g;
656		sl.sl_gnu_hash = sl.sl_gnu_hash * 33 + c;
657	}
658
659	if (req_obj->dyn.symbolic)
660		if (_dl_find_symbol_obj(req_obj, &sl))
661			goto found;
662
663	if (flags & SYM_DLSYM) {
664		struct object_vector vec;
665		int i;
666
667		if (_dl_find_symbol_obj(req_obj, &sl))
668			goto found;
669
670		/* weak definition in the specified object is good enough */
671		if (sl.sl_weak_out.sym != NULL)
672			goto found;
673
674		/* search dlopened obj and all children */
675		vec = req_obj->load_object->grpsym_vec;
676		for (i = 0; i < vec.len; i++) {
677			if (vec.vec[i] == req_obj)
678				continue;		/* already searched */
679			if (_dl_find_symbol_obj(vec.vec[i], &sl))
680				goto found;
681		}
682	} else {
683		struct dep_node *n;
684		struct object_vector vec;
685		int i, skip = 0;
686
687		if ((flags & SYM_SEARCH_SELF) || (flags & SYM_SEARCH_NEXT))
688			skip = 1;
689
690		/*
691		 * search dlopened objects: global or req_obj == dlopened_obj
692		 * and its children
693		 */
694		TAILQ_FOREACH(n, &_dlopened_child_list, next_sib) {
695			if (((n->data->obj_flags & DF_1_GLOBAL) == 0) &&
696			    (n->data != req_obj->load_object))
697				continue;
698
699			vec = n->data->grpsym_vec;
700			for (i = 0; i < vec.len; i++) {
701				if (skip == 1) {
702					if (vec.vec[i] == req_obj) {
703						skip = 0;
704						if (flags & SYM_SEARCH_NEXT)
705							continue;
706					} else
707						continue;
708				}
709				if ((flags & SYM_SEARCH_OTHER) &&
710				    (vec.vec[i] == req_obj))
711					continue;
712				if (_dl_find_symbol_obj(vec.vec[i], &sl))
713					goto found;
714			}
715		}
716	}
717
718found:
719	if (sl.sl_out.sym == NULL) {
720		if (sl.sl_weak_out.sym != NULL)
721			sl.sl_out = sl.sl_weak_out;
722		else {
723			if ((ref_sym == NULL ||
724			    (ELF_ST_BIND(ref_sym->st_info) != STB_WEAK)) &&
725			    (flags & SYM_WARNNOTFOUND))
726				_dl_printf("%s:%s: undefined symbol '%s'\n",
727				    __progname, req_obj->load_name, name);
728			return (struct sym_res){ NULL, NULL };
729		}
730	}
731
732	if (ref_sym != NULL && ref_sym->st_size != 0 &&
733	    (ref_sym->st_size != sl.sl_out.sym->st_size) &&
734	    (ELF_ST_TYPE(sl.sl_out.sym->st_info) != STT_FUNC) ) {
735		_dl_printf("%s:%s: %s : WARNING: "
736		    "symbol(%s) size mismatch, relink your program\n",
737		    __progname, req_obj->load_name, sl.sl_out.obj->load_name,
738		    name);
739	}
740
741	return sl.sl_out;
742}
743
744void
745_dl_debug_state(void)
746{
747	/* Debugger stub */
748}
749