xref: /titanic_50/usr/src/cmd/sgs/libld/common/relocate.c (revision 9d8d9e1151895fac86a2e3216647dd2a020ecf71)
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 (c) 1989, 2010, Oracle and/or its affiliates. All rights reserved.
27  */
28 
29 /*
30  * set-up for relocations
31  */
32 
33 #define	ELF_TARGET_AMD64
34 #define	ELF_TARGET_SPARC
35 
36 #include	<string.h>
37 #include	<stdio.h>
38 #include	<alloca.h>
39 #include	<debug.h>
40 #include	"msg.h"
41 #include	"_libld.h"
42 
43 /*
44  * Set up the relocation table flag test macros so that they use the
45  * relocation table for the current target machine.
46  */
47 #define	IS_PLT(X)	RELTAB_IS_PLT(X, ld_targ.t_mr.mr_reloc_table)
48 #define	IS_GOT_RELATIVE(X) \
49 	RELTAB_IS_GOT_RELATIVE(X, ld_targ.t_mr.mr_reloc_table)
50 #define	IS_GOT_PC(X)	RELTAB_IS_GOT_PC(X, ld_targ.t_mr.mr_reloc_table)
51 #define	IS_GOTPCREL(X)	RELTAB_IS_GOTPCREL(X, ld_targ.t_mr.mr_reloc_table)
52 #define	IS_GOT_BASED(X)	RELTAB_IS_GOT_BASED(X, ld_targ.t_mr.mr_reloc_table)
53 #define	IS_GOT_OPINS(X)	RELTAB_IS_GOT_OPINS(X, ld_targ.t_mr.mr_reloc_table)
54 #define	IS_GOT_REQUIRED(X) \
55 	RELTAB_IS_GOT_REQUIRED(X, ld_targ.t_mr.mr_reloc_table)
56 #define	IS_PC_RELATIVE(X) RELTAB_IS_PC_RELATIVE(X, ld_targ.t_mr.mr_reloc_table)
57 #define	IS_ADD_RELATIVE(X) \
58 	RELTAB_IS_ADD_RELATIVE(X, ld_targ.t_mr.mr_reloc_table)
59 #define	IS_REGISTER(X)	RELTAB_IS_REGISTER(X, ld_targ.t_mr.mr_reloc_table)
60 #define	IS_NOTSUP(X)	RELTAB_IS_NOTSUP(X, ld_targ.t_mr.mr_reloc_table)
61 #define	IS_SEG_RELATIVE(X) \
62 	RELTAB_IS_SEG_RELATIVE(X, ld_targ.t_mr.mr_reloc_table)
63 #define	IS_EXTOFFSET(X)	RELTAB_IS_EXTOFFSET(X, ld_targ.t_mr.mr_reloc_table)
64 #define	IS_SEC_RELATIVE(X) \
65 	RELTAB_IS_SEC_RELATIVE(X, ld_targ.t_mr.mr_reloc_table)
66 #define	IS_TLS_INS(X)	RELTAB_IS_TLS_INS(X, ld_targ.t_mr.mr_reloc_table)
67 #define	IS_TLS_GD(X)	RELTAB_IS_TLS_GD(X, ld_targ.t_mr.mr_reloc_table)
68 #define	IS_TLS_LD(X)	RELTAB_IS_TLS_LD(X, ld_targ.t_mr.mr_reloc_table)
69 #define	IS_TLS_IE(X)	RELTAB_IS_TLS_IE(X, ld_targ.t_mr.mr_reloc_table)
70 #define	IS_TLS_LE(X)	RELTAB_IS_TLS_LE(X, ld_targ.t_mr.mr_reloc_table)
71 #define	IS_LOCALBND(X)	RELTAB_IS_LOCALBND(X, ld_targ.t_mr.mr_reloc_table)
72 #define	IS_SIZE(X)	RELTAB_IS_SIZE(X, ld_targ.t_mr.mr_reloc_table)
73 
74 /*
75  * Structure to hold copy relocation items.
76  */
77 typedef struct copy_rel {
78 	Sym_desc	*c_sdp;		/* symbol descriptor to be copied */
79 	Addr 		c_val;		/* original symbol value */
80 } Copy_rel;
81 
82 /*
83  * For each copy relocation symbol, determine if the symbol is:
84  * 	1) to be *disp* relocated at runtime
85  *	2) a reference symbol for *disp* relocation
86  *	3) possibly *disp* relocated at ld time.
87  *
88  * The first and the second are serious errors.
89  */
90 static void
91 is_disp_copied(Ofl_desc *ofl, Copy_rel *crp)
92 {
93 	Ifl_desc	*ifl = crp->c_sdp->sd_file;
94 	Sym_desc	*sdp = crp->c_sdp;
95 	Addr		symaddr = crp->c_val;
96 	Is_desc		*irel;
97 	Aliste		idx;
98 	Conv_inv_buf_t	inv_buf;
99 
100 	/*
101 	 * This symbol may not be *disp* relocated at run time, but could
102 	 * already have been *disp* relocated when the shared object was
103 	 * created.  Warn the user.
104 	 */
105 	if ((ifl->ifl_flags & FLG_IF_DISPDONE) &&
106 	    (ofl->ofl_flags & FLG_OF_VERBOSE))
107 		eprintf(ofl->ofl_lml, ERR_WARNING, MSG_INTL(MSG_REL_DISPREL2),
108 		    conv_reloc_type(ifl->ifl_ehdr->e_machine,
109 		    ld_targ.t_m.m_r_copy, 0, &inv_buf),
110 		    ifl->ifl_name, demangle(sdp->sd_name));
111 
112 	if ((ifl->ifl_flags & FLG_IF_DISPPEND) == 0)
113 		return;
114 
115 	/*
116 	 * Traverse the input relocation sections.
117 	 */
118 	for (APLIST_TRAVERSE(ifl->ifl_relsect, idx, irel)) {
119 		Sym_desc	*rsdp;
120 		Is_desc		*trel;
121 		Rel		*rend, *reloc;
122 		Xword		rsize, entsize;
123 
124 		trel = ifl->ifl_isdesc[irel->is_shdr->sh_info];
125 		rsize = irel->is_shdr->sh_size;
126 		entsize = irel->is_shdr->sh_entsize;
127 		reloc = (Rel *)irel->is_indata->d_buf;
128 
129 		/*
130 		 * Decide entry size
131 		 */
132 		if ((entsize == 0) || (entsize > rsize)) {
133 			if (irel->is_shdr->sh_type == SHT_RELA)
134 				entsize = sizeof (Rela);
135 			else
136 				entsize = sizeof (Rel);
137 		}
138 
139 		/*
140 		 * Traverse the relocation entries.
141 		 */
142 		for (rend = (Rel *)((uintptr_t)reloc + (uintptr_t)rsize);
143 		    reloc < rend;
144 		    reloc = (Rel *)((uintptr_t)reloc + (uintptr_t)entsize)) {
145 			const char	*str;
146 			Word		rstndx;
147 
148 			if (IS_PC_RELATIVE(ELF_R_TYPE(reloc->r_info,
149 			    ld_targ.t_m.m_mach)) == 0)
150 				continue;
151 
152 			/*
153 			 * Determine if symbol is referenced from a relocation.
154 			 */
155 			rstndx = (Word) ELF_R_SYM(reloc->r_info);
156 			rsdp = ifl->ifl_oldndx[rstndx];
157 			if (rsdp == sdp) {
158 				if ((str = demangle(rsdp->sd_name)) !=
159 				    rsdp->sd_name) {
160 					char	*_str = alloca(strlen(str) + 1);
161 					(void) strcpy(_str, str);
162 					str = (const char *)_str;
163 				}
164 				eprintf(ofl->ofl_lml,
165 				    ERR_WARNING, MSG_INTL(MSG_REL_DISPREL1),
166 				    conv_reloc_type(ifl->ifl_ehdr->e_machine,
167 				    (uint_t)ELF_R_TYPE(reloc->r_info,
168 				    ld_targ.t_m.m_mach),
169 				    0, &inv_buf), ifl->ifl_name, str,
170 				    MSG_INTL(MSG_STR_UNKNOWN),
171 				    EC_XWORD(reloc->r_offset),
172 				    demangle(sdp->sd_name));
173 			}
174 
175 			/*
176 			 * Determine whether the relocation entry is relocating
177 			 * this symbol.
178 			 */
179 			if ((sdp->sd_isc != trel) ||
180 			    (reloc->r_offset < symaddr) ||
181 			    (reloc->r_offset >=
182 			    (symaddr + sdp->sd_sym->st_size)))
183 				continue;
184 
185 			/*
186 			 * This symbol is truely *disp* relocated, so should
187 			 * really be fixed by user.
188 			 */
189 			if ((str = demangle(sdp->sd_name)) != sdp->sd_name) {
190 				char	*_str = alloca(strlen(str) + 1);
191 				(void) strcpy(_str, str);
192 				str = (const char *)_str;
193 			}
194 			eprintf(ofl->ofl_lml, ERR_WARNING,
195 			    MSG_INTL(MSG_REL_DISPREL1),
196 			    conv_reloc_type(ifl->ifl_ehdr->e_machine,
197 			    (uint_t)ELF_R_TYPE(reloc->r_info,
198 			    ld_targ.t_m.m_mach), 0, &inv_buf),
199 			    ifl->ifl_name, demangle(rsdp->sd_name), str,
200 			    EC_XWORD(reloc->r_offset), str);
201 		}
202 	}
203 }
204 
205 /*
206  * The number of symbols provided by some objects can be very large.  Use a
207  * binary search to match the associated value to a symbol table entry.
208  */
209 static int
210 disp_bsearch(const void *key, const void *array)
211 {
212 	Addr		kvalue, avalue;
213 	Ssv_desc	*ssvp = (Ssv_desc *)array;
214 
215 	kvalue = *((Addr *)key);
216 	avalue = ssvp->ssv_value;
217 
218 	if (avalue > kvalue)
219 		return (-1);
220 	if ((avalue < kvalue) &&
221 	    ((avalue + ssvp->ssv_sdp->sd_sym->st_size) <= kvalue))
222 		return (1);
223 	return (0);
224 }
225 
226 /*
227  * Given a sorted list of symbols, look for a symbol in which the relocation
228  * offset falls between the [sym.st_value - sym.st_value + sym.st_size].  Since
229  * the symbol list is maintained in sorted order,  we can bail once the
230  * relocation offset becomes less than the symbol values.  The symbol is
231  * returned for use in error diagnostics.
232  */
233 static Sym_desc *
234 disp_scansyms(Ifl_desc * ifl, Rel_desc *rld, Boolean rlocal, int inspect,
235     Ofl_desc *ofl)
236 {
237 	Sym_desc	*tsdp, *rsdp;
238 	Sym		*rsym, *tsym;
239 	Ssv_desc	*ssvp;
240 	uchar_t		rtype, ttype;
241 	Addr		value;
242 
243 	/*
244 	 * Sorted symbol values have been uniquified by adding their associated
245 	 * section offset.  Uniquify the relocation offset by adding its
246 	 * associated section offset, and search for the symbol.
247 	 */
248 	value = rld->rel_roffset;
249 	if (rld->rel_isdesc->is_shdr)
250 		value += rld->rel_isdesc->is_shdr->sh_offset;
251 
252 	if ((ssvp = bsearch((void *)&value, (void *)ifl->ifl_sortsyms,
253 	    ifl->ifl_sortcnt, sizeof (Ssv_desc), &disp_bsearch)) != 0)
254 		tsdp = ssvp->ssv_sdp;
255 	else
256 		tsdp = 0;
257 
258 	if (inspect)
259 		return (tsdp);
260 
261 	/*
262 	 * Determine the relocation reference symbol and its type.
263 	 */
264 	rsdp = rld->rel_sym;
265 	rsym = rsdp->sd_sym;
266 	rtype = ELF_ST_TYPE(rsym->st_info);
267 
268 	/*
269 	 * If there is no target symbol to match the relocation offset, then the
270 	 * offset is effectively local data.  If the relocation symbol is global
271 	 * data we have a potential for this displacement relocation to be
272 	 * invalidated should the global symbol be copied.
273 	 */
274 	if (tsdp == 0) {
275 		if ((rlocal == TRUE) ||
276 		    ((rtype != STT_OBJECT) && (rtype != STT_SECTION)))
277 		return (tsdp);
278 	} else {
279 		/*
280 		 * If both symbols are local, no copy relocations can occur to
281 		 * either symbol.  Note, this test is very similar to the test
282 		 * used in ld_sym_adjust_vis().
283 		 */
284 		if ((rlocal == TRUE) && (SYM_IS_HIDDEN(tsdp) ||
285 		    (ELF_ST_BIND(tsdp->sd_sym->st_info) != STB_GLOBAL) ||
286 		    ((ofl->ofl_flags & (FLG_OF_AUTOLCL | FLG_OF_AUTOELM)) &&
287 		    ((tsdp->sd_flags & MSK_SY_NOAUTO) == 0))))
288 			return (tsdp);
289 
290 		/*
291 		 * Determine the relocation target symbols type.
292 		 */
293 		tsym = tsdp->sd_sym;
294 		ttype = ELF_ST_TYPE(tsym->st_info);
295 
296 		/*
297 		 * If the reference symbol is local, and the target isn't a
298 		 * data element, then no copy relocations can occur to either
299 		 * symbol.  Note, this catches pc-relative relocations against
300 		 * the _GLOBAL_OFFSET_TABLE_, which is effectively treated as
301 		 * a local symbol.
302 		 */
303 		if ((rlocal == TRUE) && (ttype != STT_OBJECT) &&
304 		    (ttype != STT_SECTION))
305 			return (tsdp);
306 
307 		/*
308 		 * Finally, one of the symbols must reference a data element.
309 		 */
310 		if ((rtype != STT_OBJECT) && (rtype != STT_SECTION) &&
311 		    (ttype != STT_OBJECT) && (ttype != STT_SECTION))
312 			return (tsdp);
313 	}
314 
315 	/*
316 	 * We have two global symbols, at least one of which is a data item.
317 	 * The last case where a displacement relocation can be ignored, is
318 	 * if the reference symbol is included in the target symbol.
319 	 */
320 	value = rsym->st_value;
321 	if ((rld->rel_flags & FLG_REL_RELA) == FLG_REL_RELA)
322 		value += rld->rel_raddend;
323 
324 	if ((rld->rel_roffset >= value) &&
325 	    (rld->rel_roffset < (value + rsym->st_size)))
326 		return (tsdp);
327 
328 	/*
329 	 * We have a displacement relocation that could be compromised by a
330 	 * copy relocation of one of the associated data items.
331 	 */
332 	rld->rel_flags |= FLG_REL_DISP;
333 	return (tsdp);
334 }
335 
336 void
337 ld_disp_errmsg(const char *msg, Rel_desc *rsp, Ofl_desc *ofl)
338 {
339 	Sym_desc	*sdp;
340 	const char	*str;
341 	Ifl_desc	*ifl = rsp->rel_isdesc->is_file;
342 	Conv_inv_buf_t	inv_buf;
343 
344 	if ((sdp = disp_scansyms(ifl, rsp, 0, 1, ofl)) != 0)
345 		str = demangle(sdp->sd_name);
346 	else
347 		str = MSG_INTL(MSG_STR_UNKNOWN);
348 
349 	eprintf(ofl->ofl_lml, ERR_WARNING, msg,
350 	    conv_reloc_type(ifl->ifl_ehdr->e_machine, rsp->rel_rtype,
351 	    0, &inv_buf), ifl->ifl_name, ld_reloc_sym_name(rsp), str,
352 	    EC_OFF(rsp->rel_roffset));
353 }
354 
355 /*
356  * qsort(3C) comparison routine used for the disp_sortsyms().
357  */
358 static int
359 disp_qsort(const void * s1, const void * s2)
360 {
361 	Ssv_desc	*ssvp1 = ((Ssv_desc *)s1);
362 	Ssv_desc	*ssvp2 = ((Ssv_desc *)s2);
363 	Addr		val1 = ssvp1->ssv_value;
364 	Addr		val2 = ssvp2->ssv_value;
365 
366 	if (val1 > val2)
367 		return (1);
368 	if (val1 < val2)
369 		return (-1);
370 	return (0);
371 }
372 
373 /*
374  * Determine whether a displacement relocation is between a local and global
375  * symbol pair.  One symbol is used to perform the relocation, and the other
376  * is the destination offset of the relocation.
377  */
378 static uintptr_t
379 disp_inspect(Ofl_desc *ofl, Rel_desc *rld, Boolean rlocal)
380 {
381 	Is_desc		*isp = rld->rel_isdesc;
382 	Ifl_desc	*ifl = rld->rel_isdesc->is_file;
383 
384 	/*
385 	 * If the input files symbols haven't been sorted yet, do so.
386 	 */
387 	if (ifl->ifl_sortsyms == 0) {
388 		Word	ondx, nndx;
389 
390 		if ((ifl->ifl_sortsyms = libld_malloc((ifl->ifl_symscnt + 1) *
391 		    sizeof (Ssv_desc))) == 0)
392 			return (S_ERROR);
393 
394 		for (ondx = 0, nndx = 0; ondx < ifl->ifl_symscnt; ondx++) {
395 			Sym_desc	*sdp;
396 			Addr		value;
397 
398 			/*
399 			 * As symbol resolution has already occurred, various
400 			 * symbols from this object may have been satisfied
401 			 * from other objects.  Only select symbols from this
402 			 * object.  For the displacement test, we only really
403 			 * need to observe data definitions, however, later as
404 			 * part of providing warning disgnostics, relating the
405 			 * relocation offset to a symbol is desirable.  Thus,
406 			 * collect all symbols that define a memory area.
407 			 */
408 			if (((sdp = ifl->ifl_oldndx[ondx]) == 0) ||
409 			    (sdp->sd_sym->st_shndx == SHN_UNDEF) ||
410 			    (sdp->sd_sym->st_shndx >= SHN_LORESERVE) ||
411 			    (sdp->sd_ref != REF_REL_NEED) ||
412 			    (sdp->sd_file != ifl) ||
413 			    (sdp->sd_sym->st_size == 0))
414 				continue;
415 
416 			/*
417 			 * As a further optimization for later checking, mark
418 			 * this section if this a global data definition.
419 			 */
420 			if (sdp->sd_isc && (ondx >= ifl->ifl_locscnt))
421 				sdp->sd_isc->is_flags |= FLG_IS_GDATADEF;
422 
423 			/*
424 			 * Capture the symbol.  Within relocatable objects, a
425 			 * symbols value is its offset within its associated
426 			 * section.  Add the section offset to this value to
427 			 * uniquify the symbol.
428 			 */
429 			value = sdp->sd_sym->st_value;
430 			if (sdp->sd_isc && sdp->sd_isc->is_shdr)
431 				value += sdp->sd_isc->is_shdr->sh_offset;
432 
433 			ifl->ifl_sortsyms[nndx].ssv_value = value;
434 			ifl->ifl_sortsyms[nndx].ssv_sdp = sdp;
435 			nndx++;
436 		}
437 
438 		/*
439 		 * Sort the list based on the symbols value (address).
440 		 */
441 		if ((ifl->ifl_sortcnt = nndx) != 0)
442 			qsort(ifl->ifl_sortsyms, nndx, sizeof (Ssv_desc),
443 			    &disp_qsort);
444 	}
445 
446 	/*
447 	 * If the reference symbol is local, and the section being relocated
448 	 * contains no global definitions, neither can be the target of a copy
449 	 * relocation.
450 	 */
451 	if ((rlocal == FALSE) && ((isp->is_flags & FLG_IS_GDATADEF) == 0))
452 		return (1);
453 
454 	/*
455 	 * Otherwise determine whether this relocation symbol and its offset
456 	 * could be candidates for a copy relocation.
457 	 */
458 	if (ifl->ifl_sortcnt)
459 		(void) disp_scansyms(ifl, rld, rlocal, 0, ofl);
460 	return (1);
461 }
462 
463 /*
464  * Return a Rel_cachebuf with an available Rel_desc entry from the
465  * specified cache, allocating a cache buffer if necessary.
466  *
467  * entry:
468  *	ofl - Output file descriptor
469  *	rcp - Relocation cache to allocate the descriptor from.
470  *		One of &ofl->ofl_actrels or &ofl->ofl_outrels.
471  *
472  * exit:
473  *	Returns the allocated descriptor, or NULL if the allocation fails.
474  */
475 static Rel_cachebuf *
476 ld_add_rel_cache(Ofl_desc *ofl, Rel_cache *rcp)
477 {
478 	Rel_cachebuf	*rcbp;
479 	size_t		nelts, size, alloc_cnt;
480 
481 	/*
482 	 * If there is space available in the present cache bucket, return the
483 	 * next free entry.
484 	 */
485 	alloc_cnt = aplist_nitems(rcp->rc_list);
486 	if (rcp->rc_list &&
487 	    ((rcbp = rcp->rc_list->apl_data[alloc_cnt - 1]) != NULL) &&
488 	    (rcbp->rc_free < rcbp->rc_end))
489 		return (rcbp);
490 
491 	/*
492 	 * Allocate a new bucket. As we cannot know the number of relocations
493 	 * we'll have in the active and output cache until after the link is
494 	 * complete, the size of the bucket is a heuristic.
495 	 *
496 	 * In general, if the output object is an executable, or a sharable
497 	 * object, then the size of the active relocation list will be nearly
498 	 * the same as the number of input relocations, and the output
499 	 * relocation list will be very short. If the output object is a
500 	 * relocatable object, then the reverse is true. Therefore, the initial
501 	 * allocation for the appropriate list is sized to fit all the input
502 	 * allocations in a single shot.
503 	 *
504 	 * All other allocations are done in units of REL_CACHEBUF_ALLOC,
505 	 * which is chosen to be large enough to cover most common cases,
506 	 * but small enough that not using it fully is inconsequential.
507 	 *
508 	 * In an ideal scenario, this results in one allocation on each list.
509 	 */
510 	nelts = REL_CACHEBUF_ALLOC;
511 	if ((alloc_cnt == 0) && (ofl->ofl_relocincnt > REL_CACHEBUF_ALLOC)) {
512 		Boolean is_rel = (ofl->ofl_flags & FLG_OF_RELOBJ) != 0;
513 
514 		if (((rcp == &ofl->ofl_actrels) && !is_rel) ||
515 		    ((rcp == &ofl->ofl_outrels) && is_rel))
516 			nelts = ofl->ofl_relocincnt;
517 	}
518 
519 	/*
520 	 * Compute the total number of bytes to allocate. The first element
521 	 * of the array is built into the Rel_cachebuf header, so we subtract
522 	 * one from nelts.
523 	 */
524 	size = sizeof (Rel_cachebuf) + ((nelts - 1) * sizeof (Rel_desc));
525 
526 	if (((rcbp = libld_malloc(size)) == NULL) ||
527 	    (aplist_append(&rcp->rc_list, rcbp, AL_CNT_OFL_RELS) == NULL))
528 		return (NULL);
529 
530 	rcbp->rc_free = rcbp->rc_arr;
531 	rcbp->rc_end = rcbp->rc_arr + nelts;
532 
533 	return (rcbp);
534 }
535 
536 /*
537  * Allocate a Rel_aux descriptor and attach it to the given Rel_desc,
538  * allocating an auxiliary cache buffer if necessary.
539  *
540  * entry:
541  *	ofl - Output file descriptor
542  *	rdp - Rel_desc descriptor that requires an auxiliary block
543  *
544  * exit:
545  *	Returns TRUE on success, and FALSE if the allocation fails.
546  *	On success, the caller is responsible for initializing the
547  *	auxiliary block properly.
548  */
549 static Boolean
550 ld_add_rel_aux(Ofl_desc *ofl, Rel_desc *rdesc)
551 {
552 	Rel_aux_cachebuf	*racp = NULL;
553 	size_t			size;
554 
555 	/*
556 	 * If there is space available in the present cache bucket, use it.
557 	 * Otherwise, allocate a new bucket.
558 	 */
559 	if (ofl->ofl_relaux) {
560 		racp = ofl->ofl_relaux->apl_data[
561 		    ofl->ofl_relaux->apl_nitems - 1];
562 
563 		if (racp && (racp->rac_free >= racp->rac_end))
564 			racp = NULL;
565 	}
566 	if (racp == NULL) {
567 		/*
568 		 * Compute the total number of bytes to allocate. The first
569 		 * element of the array is built into the Rel_aux_cachebuf
570 		 * header, so we subtract one from the number of elements.
571 		 */
572 		size = sizeof (Rel_aux_cachebuf) +
573 		    ((RELAUX_CACHEBUF_ALLOC - 1) * sizeof (Rel_aux));
574 		if (((racp = libld_malloc(size)) == NULL) ||
575 		    (aplist_append(&ofl->ofl_relaux, racp, AL_CNT_OFL_RELS) ==
576 		    NULL))
577 			return (FALSE);
578 
579 		racp->rac_free = racp->rac_arr;
580 		racp->rac_end = racp->rac_arr + RELAUX_CACHEBUF_ALLOC;
581 	}
582 
583 	/* Take an auxiliary descriptor from the cache and add it to rdesc */
584 	rdesc->rel_aux = racp->rac_free++;
585 
586 	return (TRUE);
587 }
588 
589 /*
590  * Enter a copy of the given Rel_desc relocation descriptor, and
591  * any associated auxiliary Rel_aux it may reference, into the
592  * specified relocation cache.
593  *
594  * entry:
595  *	ofl - Output file descriptor
596  *	rcp - Relocation descriptor cache to recieve relocation
597  *	rdesc - Rel_desc image to be inserted
598  *	flags - Flags to add to rdest->rel_flags in the inserted descriptor
599  *
600  * exit:
601  *	Returns the pointer to the inserted descriptor on success.
602  *	Returns NULL if an allocation error occurs.
603  */
604 Rel_desc *
605 ld_reloc_enter(Ofl_desc *ofl, Rel_cache *rcp, Rel_desc *rdesc, Word flags)
606 {
607 	Rel_desc	*arsp;
608 	Rel_aux		*auxp;
609 	Rel_cachebuf	*rcbp;
610 
611 
612 	/*
613 	 * If no relocation cache structures are available, allocate a new
614 	 * one and link it to the buffer list.
615 	 */
616 	rcbp = ld_add_rel_cache(ofl, rcp);
617 	if (rcbp == NULL)
618 		return (NULL);
619 	arsp = rcbp->rc_free;
620 
621 	/*
622 	 * If there is an auxiliary block on the original, allocate
623 	 * one for the clone. Save the pointer, because the struct copy
624 	 * below will crush it.
625 	 */
626 	if (rdesc->rel_aux != NULL) {
627 		if (!ld_add_rel_aux(ofl, arsp))
628 			return (NULL);
629 		auxp = arsp->rel_aux;
630 	}
631 
632 	/* Copy contents of the original into the clone */
633 	*arsp = *rdesc;
634 
635 	/*
636 	 * If there is an auxiliary block, restore the clone's pointer to
637 	 * it, and copy the auxiliary contents.
638 	 */
639 	if (rdesc->rel_aux != NULL) {
640 		arsp->rel_aux = auxp;
641 		*auxp = *rdesc->rel_aux;
642 	}
643 	arsp->rel_flags |= flags;
644 
645 	rcbp->rc_free++;
646 	rcp->rc_cnt++;
647 
648 	return (arsp);
649 }
650 
651 /*
652  * Initialize a relocation descriptor auxiliary block to default
653  * values.
654  *
655  * entry:
656  *	rdesc - Relocation descriptor, with a non-NULL rel_aux field
657  *		pointing at the auxiliary block to be initialized.
658  *
659  * exit:
660  *	Each field in rdesc->rel_aux has been set to its default value
661  */
662 static void
663 ld_init_rel_aux(Rel_desc *rdesc)
664 {
665 	Rel_aux	*rap = rdesc->rel_aux;
666 
667 	/*
668 	 * The default output section is the one the input section
669 	 * is assigned to, assuming that there is an input section.
670 	 * Failing that, NULL is the only possibility, and we expect
671 	 * that the caller will assign an explicit value.
672 	 */
673 	rap->ra_osdesc = (rdesc->rel_isdesc == NULL) ? NULL :
674 	    rdesc->rel_isdesc->is_osdesc;
675 
676 	/* The ra_usym defaults to the value in rel_sym */
677 	rap->ra_usym = rdesc->rel_sym;
678 
679 	/* Remaining fields are zeroed */
680 	rap->ra_move = NULL;
681 	rap->ra_typedata = 0;
682 }
683 
684 /*
685  * The ld_reloc_set_aux_XXX() functions are used to set the value of an
686  * auxiliary relocation item on a relocation descriptor that exists in
687  * the active or output relocation cache. These descriptors are created
688  * via a call to ld_reloc_enter().
689  *
690  * These functions preserve the illusion that every relocation descriptor
691  * has a non-NULL auxiliary block into which values can be set, while
692  * only creating an auxiliary block if one is actually necessary, preventing
693  * the large memory allocations that would otherwise occur. They operate
694  * as follows:
695  *
696  * -	If an auxiliary block already exists, set the desired value and
697  *	and return TRUE.
698  *
699  * -	If no auxiliary block exists, but the desired value is the default
700  *	value for the specified item, then no auxiliary block is needed,
701  *	and TRUE is returned.
702  *
703  * -	If no auxiliary block exists, and the desired value is not the
704  *	default for the specified item, allocate an auxiliary block for
705  *	the descriptor, initialize its contents to default values for all
706  *	items, set the specified value, and return TRUE.
707  *
708  * -	If an auxiliary block needs to be added, but the allocation fails,
709  *	an error is issued, and FALSE is returned.
710  *
711  * Note that we only provide an ld_reloc_set_aux_XXX() function for those
712  * auxiliary items that libld actually modifies in Rel_desc descriptors
713  * in the active or output caches. If another one is needed, add it here.
714  *
715  * The PROCESS_NULL_REL_AUX macro is used to provide a single implementation
716  * for the logic that determines if an auxiliary block is needed or not,
717  * and handles the details of allocating and initializing it. It accepts
718  * one argument, _isdefault_predicate, which should be a call to the
719  * RELAUX_ISDEFAULT_xxx() macro appropriate for the auxiliary item
720  */
721 
722 #define	PROCESS_NULL_REL_AUX(_isdefault_predicate) \
723 	if (rdesc->rel_aux == NULL) { \
724 		/* If requested value is the default, no need for aux block */ \
725 		if (_isdefault_predicate) \
726 			return (TRUE); \
727 		/* Allocate and attach an auxiliary block */ \
728 		if (!ld_add_rel_aux(ofl, rdesc)) \
729 			return (FALSE); \
730 		/* Initialize the auxiliary block with default values */ \
731 		ld_init_rel_aux(rdesc); \
732 	}
733 
734 Boolean
735 ld_reloc_set_aux_osdesc(Ofl_desc *ofl, Rel_desc *rdesc, Os_desc *osp)
736 {
737 	PROCESS_NULL_REL_AUX(RELAUX_ISDEFAULT_OSDESC(rdesc, osp))
738 	rdesc->rel_aux->ra_osdesc = osp;
739 	return (TRUE);
740 }
741 
742 Boolean
743 ld_reloc_set_aux_usym(Ofl_desc *ofl, Rel_desc *rdesc, Sym_desc *sdp)
744 {
745 	PROCESS_NULL_REL_AUX(RELAUX_ISDEFAULT_USYM(rdesc, sdp))
746 	rdesc->rel_aux->ra_usym = sdp;
747 	return (TRUE);
748 }
749 
750 #undef PROCESS_NULL_REL_AUX
751 
752 /*
753  * Return a descriptive name for the symbol associated with the
754  * given relocation descriptor. This will be the actual symbol
755  * name if one exists, or a suitable alternative otherwise.
756  *
757  * entry:
758  *	rsp - Relocation descriptor
759  */
760 const char *
761 ld_reloc_sym_name(Rel_desc *rsp)
762 {
763 	Sym_desc	*sdp = rsp->rel_sym;
764 
765 	if (sdp != NULL) {
766 		/* If the symbol has a valid name use it */
767 		if (sdp->sd_name && *sdp->sd_name)
768 			return (demangle(sdp->sd_name));
769 
770 		/*
771 		 * If the symbol is STT_SECTION, and the corresponding
772 		 * section symbol has the specially prepared string intended
773 		 * for this use, use that string. The string is of the form
774 		 *	secname (section)
775 		 */
776 		if ((ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION) &&
777 		    (sdp->sd_isc != NULL) && (sdp->sd_isc->is_sym_name != NULL))
778 			return (demangle(sdp->sd_isc->is_sym_name));
779 	} else {
780 		/*
781 		 * Use an empty name for a register relocation with
782 		 * no symbol.
783 		 */
784 		if (IS_REGISTER(rsp->rel_rtype))
785 			return (MSG_ORIG(MSG_STR_EMPTY));
786 	}
787 
788 	/* If all else fails, report it as <unknown> */
789 	return (MSG_INTL(MSG_STR_UNKNOWN));
790 }
791 
792 /*
793  * Add an active relocation record.
794  */
795 uintptr_t
796 ld_add_actrel(Word flags, Rel_desc *rsp, Ofl_desc *ofl)
797 {
798 	Rel_desc	*arsp;
799 
800 	if ((arsp = ld_reloc_enter(ofl, &ofl->ofl_actrels, rsp, flags)) == NULL)
801 		return (S_ERROR);
802 
803 	/*
804 	 * Any GOT relocation reference requires the creation of a .got table.
805 	 * Most references to a .got require a .got entry,  which is accounted
806 	 * for with the ofl_gotcnt counter.  However, some references are
807 	 * relative to the .got table, but require no .got entry.  This test
808 	 * insures a .got is created regardless of the type of reference.
809 	 */
810 	if (IS_GOT_REQUIRED(arsp->rel_rtype))
811 		ofl->ofl_flags |= FLG_OF_BLDGOT;
812 
813 	/*
814 	 * If this is a displacement relocation generate a warning.
815 	 */
816 	if (arsp->rel_flags & FLG_REL_DISP) {
817 		ofl->ofl_dtflags_1 |= DF_1_DISPRELDNE;
818 
819 		if (ofl->ofl_flags & FLG_OF_VERBOSE)
820 			ld_disp_errmsg(MSG_INTL(MSG_REL_DISPREL3), arsp, ofl);
821 	}
822 
823 	DBG_CALL(Dbg_reloc_ars_entry(ofl->ofl_lml, ELF_DBG_LD,
824 	    arsp->rel_isdesc->is_shdr->sh_type, ld_targ.t_m.m_mach, arsp));
825 	return (1);
826 }
827 
828 /*
829  * In the platform specific machrel.XXX.c files, we sometimes write
830  * a value directly into the got/plt. These function can be used when
831  * the running linker has the opposite byte order of the object being
832  * produced.
833  */
834 Word
835 ld_bswap_Word(Word v)
836 {
837 	return (BSWAP_WORD(v));
838 }
839 
840 
841 Xword
842 ld_bswap_Xword(Xword v)
843 {
844 	return (BSWAP_XWORD(v));
845 }
846 
847 
848 uintptr_t
849 ld_reloc_GOT_relative(Boolean local, Rel_desc *rsp, Ofl_desc *ofl)
850 {
851 	Sym_desc	*sdp = rsp->rel_sym;
852 	ofl_flag_t	flags = ofl->ofl_flags;
853 	Gotndx		*gnp;
854 
855 	/*
856 	 * If this is the first time we've seen this symbol in a GOT
857 	 * relocation we need to assign it a GOT token.  Once we've got
858 	 * all of the GOT's assigned we can assign the actual indexes.
859 	 */
860 	if ((gnp = (*ld_targ.t_mr.mr_find_got_ndx)(sdp->sd_GOTndxs,
861 	    GOT_REF_GENERIC, ofl, rsp)) == 0) {
862 		Word	rtype = rsp->rel_rtype;
863 
864 		if ((*ld_targ.t_mr.mr_assign_got_ndx)(&(sdp->sd_GOTndxs), NULL,
865 		    GOT_REF_GENERIC, ofl, rsp, sdp) == S_ERROR)
866 			return (S_ERROR);
867 
868 		/*
869 		 * Now we initialize the GOT table entry.
870 		 *
871 		 * Pseudo code to describe the the decisions below:
872 		 *
873 		 * If (local)
874 		 * then
875 		 *	enter symbol value in GOT table entry
876 		 *	if (Shared Object)
877 		 *	then
878 		 *		create Relative relocation against symbol
879 		 *	fi
880 		 * else
881 		 *	clear GOT table entry
882 		 *	create a GLOB_DAT relocation against symbol
883 		 * fi
884 		 */
885 		if (local == TRUE) {
886 			if (flags & FLG_OF_SHAROBJ) {
887 				if (ld_add_actrel((FLG_REL_GOT | FLG_REL_GOTCL),
888 				    rsp, ofl) == S_ERROR)
889 					return (S_ERROR);
890 
891 				/*
892 				 * Add a RELATIVE relocation if this is
893 				 * anything but a ABS symbol.
894 				 */
895 				if ((((sdp->sd_flags & FLG_SY_SPECSEC) == 0) ||
896 				    (sdp->sd_sym->st_shndx != SHN_ABS)) ||
897 				    (sdp->sd_aux && sdp->sd_aux->sa_symspec)) {
898 					rsp->rel_rtype =
899 					    ld_targ.t_m.m_r_relative;
900 					if ((*ld_targ.t_mr.mr_add_outrel)
901 					    ((FLG_REL_GOT | FLG_REL_ADVAL), rsp,
902 					    ofl) == S_ERROR)
903 						return (S_ERROR);
904 					rsp->rel_rtype = rtype;
905 				}
906 			} else {
907 				if (ld_add_actrel(FLG_REL_GOT, rsp,
908 				    ofl) == S_ERROR)
909 					return (S_ERROR);
910 			}
911 		} else {
912 			rsp->rel_rtype = ld_targ.t_m.m_r_glob_dat;
913 			if ((*ld_targ.t_mr.mr_add_outrel)(FLG_REL_GOT,
914 			    rsp, ofl) == S_ERROR)
915 				return (S_ERROR);
916 			rsp->rel_rtype = rtype;
917 		}
918 	} else {
919 		if ((*ld_targ.t_mr.mr_assign_got_ndx)(&(sdp->sd_GOTndxs), gnp,
920 		    GOT_REF_GENERIC, ofl, rsp, sdp) == S_ERROR)
921 			return (S_ERROR);
922 	}
923 
924 	/*
925 	 * Perform relocation to GOT table entry.
926 	 */
927 	return (ld_add_actrel(NULL, rsp, ofl));
928 }
929 
930 /*
931  * Perform relocations for PLT's
932  */
933 uintptr_t
934 ld_reloc_plt(Rel_desc *rsp, Ofl_desc *ofl)
935 {
936 	Sym_desc	*sdp = rsp->rel_sym;
937 
938 	switch (ld_targ.t_m.m_mach) {
939 	case EM_AMD64:
940 		/*
941 		 * AMD64 TLS code sequences do not use a unique TLS
942 		 * relocation to reference the __tls_get_addr() function call.
943 		 */
944 		if ((ofl->ofl_flags & FLG_OF_EXEC) &&
945 		    (strcmp(sdp->sd_name, MSG_ORIG(MSG_SYM_TLSGETADDR_U)) ==
946 		    0))
947 			return (ld_add_actrel(FLG_REL_TLSFIX, rsp, ofl));
948 		break;
949 
950 	case EM_386:
951 		/*
952 		 * GNUC IA32 TLS code sequences do not use a unique TLS
953 		 * relocation to reference the ___tls_get_addr() function call.
954 		 */
955 		if ((ofl->ofl_flags & FLG_OF_EXEC) &&
956 		    (strcmp(sdp->sd_name, MSG_ORIG(MSG_SYM_TLSGETADDR_UU)) ==
957 		    0))
958 			return (ld_add_actrel(FLG_REL_TLSFIX, rsp, ofl));
959 		break;
960 	}
961 
962 	/*
963 	 * if (not PLT yet assigned)
964 	 * then
965 	 *	assign PLT index to symbol
966 	 *	build output JMP_SLOT relocation
967 	 * fi
968 	 */
969 	if (sdp->sd_aux->sa_PLTndx == 0) {
970 		Word	ortype = rsp->rel_rtype;
971 
972 		(*ld_targ.t_mr.mr_assign_plt_ndx)(sdp, ofl);
973 
974 		/*
975 		 * If this symbol is binding to a LAZYLOADED object then
976 		 * set the LAZYLD symbol flag.
977 		 */
978 		if (sdp->sd_file &&
979 		    (sdp->sd_file->ifl_flags & FLG_IF_LAZYLD))
980 			sdp->sd_flags |= FLG_SY_LAZYLD;
981 
982 		rsp->rel_rtype = ld_targ.t_m.m_r_jmp_slot;
983 		if ((*ld_targ.t_mr.mr_add_outrel)(FLG_REL_PLT, rsp, ofl) ==
984 		    S_ERROR)
985 			return (S_ERROR);
986 		rsp->rel_rtype = ortype;
987 	}
988 
989 	/*
990 	 * Perform relocation to PLT table entry.
991 	 */
992 	if ((ofl->ofl_flags & FLG_OF_SHAROBJ) &&
993 	    IS_ADD_RELATIVE(rsp->rel_rtype)) {
994 		Word	ortype	= rsp->rel_rtype;
995 
996 		rsp->rel_rtype = ld_targ.t_m.m_r_relative;
997 		if ((*ld_targ.t_mr.mr_add_outrel)(FLG_REL_ADVAL, rsp, ofl) ==
998 		    S_ERROR)
999 			return (S_ERROR);
1000 		rsp->rel_rtype = ortype;
1001 		return (1);
1002 	} else
1003 		return (ld_add_actrel(NULL, rsp, ofl));
1004 }
1005 
1006 /*
1007  * process GLOBAL undefined and ref_dyn_need symbols.
1008  */
1009 static uintptr_t
1010 reloc_exec(Rel_desc *rsp, Ofl_desc *ofl)
1011 {
1012 	Sym_desc	*_sdp, *sdp = rsp->rel_sym;
1013 	Sym_aux		*sap = sdp->sd_aux;
1014 	Sym		*sym = sdp->sd_sym;
1015 	Addr		stval;
1016 
1017 	/*
1018 	 * Reference is to a function so simply create a plt entry for it.
1019 	 */
1020 	if (ELF_ST_TYPE(sym->st_info) == STT_FUNC)
1021 		return (ld_reloc_plt(rsp, ofl));
1022 
1023 	/*
1024 	 * Catch absolutes - these may cause a text relocation.
1025 	 */
1026 	if ((sdp->sd_flags & FLG_SY_SPECSEC) && (sym->st_shndx == SHN_ABS)) {
1027 		if ((ofl->ofl_flags1 & FLG_OF1_ABSEXEC) == 0)
1028 			return ((*ld_targ.t_mr.mr_add_outrel)(NULL, rsp, ofl));
1029 
1030 		/*
1031 		 * If -zabsexec is set then promote the ABSOLUTE symbol to
1032 		 * current the current object and perform the relocation now.
1033 		 */
1034 		sdp->sd_ref = REF_REL_NEED;
1035 		return (ld_add_actrel(NULL, rsp, ofl));
1036 	}
1037 
1038 	/*
1039 	 * If the relocation is against a writable section simply compute the
1040 	 * necessary output relocation.  As an optimization, if the symbol has
1041 	 * already been transformed into a copy relocation then we can perform
1042 	 * the relocation directly (copy relocations should only be generated
1043 	 * for references from the text segment and these relocations are
1044 	 * normally carried out before we get to the data segment relocations).
1045 	 */
1046 	if ((ELF_ST_TYPE(sym->st_info) == STT_OBJECT) &&
1047 	    (RELAUX_GET_OSDESC(rsp)->os_shdr->sh_flags & SHF_WRITE)) {
1048 		if (sdp->sd_flags & FLG_SY_MVTOCOMM)
1049 			return (ld_add_actrel(NULL, rsp, ofl));
1050 		else
1051 			return ((*ld_targ.t_mr.mr_add_outrel)(NULL, rsp, ofl));
1052 	}
1053 
1054 	/*
1055 	 * If the reference isn't to an object (normally because a .type
1056 	 * directive hasn't defined in some assembler source), then simply apply
1057 	 * a generic relocation (this has a tendency to result in text
1058 	 * relocations).
1059 	 */
1060 	if (ELF_ST_TYPE(sym->st_info) != STT_OBJECT) {
1061 		Conv_inv_buf_t inv_buf;
1062 
1063 		eprintf(ofl->ofl_lml, ERR_WARNING, MSG_INTL(MSG_REL_UNEXPSYM),
1064 		    conv_sym_info_type(sdp->sd_file->ifl_ehdr->e_machine,
1065 		    ELF_ST_TYPE(sym->st_info), 0, &inv_buf),
1066 		    rsp->rel_isdesc->is_file->ifl_name,
1067 		    ld_reloc_sym_name(rsp), sdp->sd_file->ifl_name);
1068 		return ((*ld_targ.t_mr.mr_add_outrel)(NULL, rsp, ofl));
1069 	}
1070 
1071 	/*
1072 	 * Prepare for generating a copy relocation.
1073 	 *
1074 	 * If this symbol is one of an alias pair, we need to insure both
1075 	 * symbols become part of the output (the strong symbol will be used to
1076 	 * maintain the symbols state).  And, if we did raise the precedence of
1077 	 * a symbol we need to check and see if this is a weak symbol.  If it is
1078 	 * we want to use it's strong counter part.
1079 	 *
1080 	 * The results of this logic should be:
1081 	 *	ra_usym: assigned to strong
1082 	 *	rel_sym: assigned to symbol to perform
1083 	 *		copy_reloc against (weak or strong).
1084 	 */
1085 	if (sap->sa_linkndx) {
1086 		_sdp = sdp->sd_file->ifl_oldndx[sap->sa_linkndx];
1087 
1088 		if (_sdp->sd_ref < sdp->sd_ref) {
1089 			_sdp->sd_ref = sdp->sd_ref;
1090 			_sdp->sd_flags |= FLG_SY_REFRSD;
1091 
1092 			/*
1093 			 * As we're going to replicate a symbol from a shared
1094 			 * object, retain its correct binding status.
1095 			 */
1096 			if (ELF_ST_BIND(_sdp->sd_sym->st_info) == STB_GLOBAL)
1097 				_sdp->sd_flags |= FLG_SY_GLOBREF;
1098 
1099 		} else if (_sdp->sd_ref > sdp->sd_ref) {
1100 			sdp->sd_ref = _sdp->sd_ref;
1101 			sdp->sd_flags |= FLG_SY_REFRSD;
1102 
1103 			/*
1104 			 * As we're going to replicate a symbol from a shared
1105 			 * object, retain its correct binding status.
1106 			 */
1107 			if (ELF_ST_BIND(sym->st_info) == STB_GLOBAL)
1108 				sdp->sd_flags |= FLG_SY_GLOBREF;
1109 		}
1110 
1111 		/*
1112 		 * If this is a weak symbol then we want to move the strong
1113 		 * symbol into local .bss.  If there is a copy_reloc to be
1114 		 * performed, that should still occur against the WEAK symbol.
1115 		 */
1116 		if (((ELF_ST_BIND(sdp->sd_sym->st_info) == STB_WEAK) ||
1117 		    (sdp->sd_flags & FLG_SY_WEAKDEF)) &&
1118 		    !ld_reloc_set_aux_usym(ofl, rsp, _sdp))
1119 			return (S_ERROR);
1120 	} else
1121 		_sdp = 0;
1122 
1123 	/*
1124 	 * If the reference is to an object then allocate space for the object
1125 	 * within the executables .bss.  Relocations will now be performed from
1126 	 * this new location.  If the original shared objects data is
1127 	 * initialized, then generate a copy relocation that will copy the data
1128 	 * to the executables .bss at runtime.
1129 	 */
1130 	if (!(RELAUX_GET_USYM(rsp)->sd_flags & FLG_SY_MVTOCOMM)) {
1131 		Word		rtype = rsp->rel_rtype;
1132 		Copy_rel	cr;
1133 
1134 		/*
1135 		 * Indicate that the symbol(s) against which we're relocating
1136 		 * have been moved to the executables common.  Also, insure that
1137 		 * the symbol(s) remain marked as global, as the shared object
1138 		 * from which they are copied must be able to relocate to the
1139 		 * new common location within the executable.
1140 		 *
1141 		 * Note that even though a new symbol has been generated in the
1142 		 * output files' .bss, the symbol must remain REF_DYN_NEED and
1143 		 * not be promoted to REF_REL_NEED.  sym_validate() still needs
1144 		 * to carry out a number of checks against the symbols binding
1145 		 * that are triggered by the REF_DYN_NEED state.
1146 		 */
1147 		sdp->sd_flags |=
1148 		    (FLG_SY_MVTOCOMM | FLG_SY_DEFAULT | FLG_SY_EXPDEF);
1149 		sdp->sd_flags &= ~MSK_SY_LOCAL;
1150 		sdp->sd_sym->st_other &= ~MSK_SYM_VISIBILITY;
1151 		if (_sdp) {
1152 			_sdp->sd_flags |= (FLG_SY_MVTOCOMM |
1153 			    FLG_SY_DEFAULT | FLG_SY_EXPDEF);
1154 			_sdp->sd_flags &= ~MSK_SY_LOCAL;
1155 			_sdp->sd_sym->st_other &= ~MSK_SYM_VISIBILITY;
1156 
1157 			/*
1158 			 * Make sure the symbol has a reference in case of any
1159 			 * error diagnostics against it (perhaps this belongs
1160 			 * to a version that isn't allowable for this build).
1161 			 * The resulting diagnostic (see sym_undef_entry())
1162 			 * might seem a little bogus, as the symbol hasn't
1163 			 * really been referenced by this file, but has been
1164 			 * promoted as a consequence of its alias reference.
1165 			 */
1166 			if (!(_sdp->sd_aux->sa_rfile))
1167 				_sdp->sd_aux->sa_rfile = sdp->sd_aux->sa_rfile;
1168 		}
1169 
1170 		/*
1171 		 * Assign the symbol to the bss and insure sufficient alignment
1172 		 * (we don't know the real alignment so we have to make the
1173 		 * worst case guess).
1174 		 */
1175 		_sdp = RELAUX_GET_USYM(rsp);
1176 		stval = _sdp->sd_sym->st_value;
1177 		if (ld_sym_copy(_sdp) == S_ERROR)
1178 			return (S_ERROR);
1179 		_sdp->sd_shndx = _sdp->sd_sym->st_shndx = SHN_COMMON;
1180 		_sdp->sd_flags |= FLG_SY_SPECSEC;
1181 		_sdp->sd_sym->st_value =
1182 		    (_sdp->sd_sym->st_size < (ld_targ.t_m.m_word_align * 2)) ?
1183 		    ld_targ.t_m.m_word_align : ld_targ.t_m.m_word_align * 2;
1184 
1185 		/*
1186 		 * Whether or not the symbol references initialized data we
1187 		 * generate a copy relocation - this differs from the past
1188 		 * where we would not create the COPY_RELOC if we were binding
1189 		 * against .bss.  This is done for *two* reasons.
1190 		 *
1191 		 *  -	If the symbol in the shared object changes to a
1192 		 *	initialized data - we need the COPY to pick it up.
1193 		 *  -	Without the COPY RELOC we can't tell that the symbol
1194 		 *	from the COPY'd object has been moved and all bindings
1195 		 *	to it should bind here.
1196 		 *
1197 		 * Keep this symbol in the copy relocation list to check the
1198 		 * validity later.
1199 		 */
1200 		cr.c_sdp = _sdp;
1201 		cr.c_val = stval;
1202 		if (alist_append(&ofl->ofl_copyrels, &cr, sizeof (Copy_rel),
1203 		    AL_CNT_OFL_COPYRELS) == NULL)
1204 			return (S_ERROR);
1205 
1206 		rsp->rel_rtype = ld_targ.t_m.m_r_copy;
1207 		if ((*ld_targ.t_mr.mr_add_outrel)(FLG_REL_BSS, rsp, ofl) ==
1208 		    S_ERROR)
1209 			return (S_ERROR);
1210 		rsp->rel_rtype = rtype;
1211 
1212 		/*
1213 		 * If this symbol is a protected symbol, warn it.
1214 		 */
1215 		if (_sdp->sd_flags & FLG_SY_PROT) {
1216 			Conv_inv_buf_t inv_buf;
1217 
1218 			eprintf(ofl->ofl_lml, ERR_WARNING,
1219 			    MSG_INTL(MSG_REL_COPY),
1220 			    conv_reloc_type(_sdp->sd_file->ifl_ehdr->e_machine,
1221 			    ld_targ.t_m.m_r_copy, 0, &inv_buf),
1222 			    _sdp->sd_file->ifl_name, _sdp->sd_name);
1223 		}
1224 		DBG_CALL(Dbg_syms_reloc(ofl, sdp));
1225 	}
1226 	return (ld_add_actrel(NULL, rsp, ofl));
1227 }
1228 
1229 /*
1230  * All relocations should have been handled by the other routines.  This
1231  * routine is here as a catch all, if we do enter it we've goofed - but
1232  * we'll try and do the best we can.
1233  */
1234 static uintptr_t
1235 reloc_generic(Rel_desc *rsp, Ofl_desc *ofl)
1236 {
1237 	Ifl_desc	*ifl = rsp->rel_isdesc->is_file;
1238 	Conv_inv_buf_t	inv_buf;
1239 
1240 	eprintf(ofl->ofl_lml, ERR_WARNING, MSG_INTL(MSG_REL_UNEXPREL),
1241 	    conv_reloc_type(ifl->ifl_ehdr->e_machine, rsp->rel_rtype,
1242 	    0, &inv_buf), ifl->ifl_name, ld_reloc_sym_name(rsp));
1243 
1244 	/*
1245 	 * If building a shared object then put the relocation off
1246 	 * until runtime.
1247 	 */
1248 	if (ofl->ofl_flags & FLG_OF_SHAROBJ)
1249 		return ((*ld_targ.t_mr.mr_add_outrel)(NULL, rsp, ofl));
1250 
1251 	/*
1252 	 * Otherwise process relocation now.
1253 	 */
1254 	return (ld_add_actrel(NULL, rsp, ofl));
1255 }
1256 
1257 /*
1258  * Process relocations when building a relocatable object.  Typically, there
1259  * aren't many relocations that can be caught at this point, most are simply
1260  * passed through to the output relocatable object.
1261  */
1262 static uintptr_t
1263 reloc_relobj(Boolean local, Rel_desc *rsp, Ofl_desc *ofl)
1264 {
1265 	Word		rtype = rsp->rel_rtype;
1266 	Sym_desc	*sdp = rsp->rel_sym;
1267 	Is_desc		*isp = rsp->rel_isdesc;
1268 	Word		oflags = NULL;
1269 
1270 	/*
1271 	 * Determine if we can do any relocations at this point.  We can if:
1272 	 *
1273 	 *	this is local_symbol and a non-GOT relocation, and
1274 	 *	the relocation is pc-relative, and
1275 	 *	the relocation is against a symbol in same section
1276 	 */
1277 	if (local && !IS_GOT_RELATIVE(rtype) &&
1278 	    !IS_GOT_BASED(rtype) && !IS_GOT_PC(rtype) &&
1279 	    IS_PC_RELATIVE(rtype) &&
1280 	    ((sdp->sd_isc) && (sdp->sd_isc->is_osdesc == isp->is_osdesc)))
1281 		return (ld_add_actrel(NULL, rsp, ofl));
1282 
1283 	/*
1284 	 * If -zredlocsym is in effect, translate all local symbol relocations
1285 	 * to be against section symbols, since section symbols are the only
1286 	 * local symbols which will be added to the .symtab.
1287 	 */
1288 	if (local && (((ofl->ofl_flags & FLG_OF_REDLSYM) &&
1289 	    (ELF_ST_BIND(sdp->sd_sym->st_info) == STB_LOCAL)) ||
1290 	    ((sdp->sd_flags & FLG_SY_ELIM) &&
1291 	    (ofl->ofl_flags & FLG_OF_PROCRED)))) {
1292 		/*
1293 		 * But if this is PIC code, don't allow it for now.
1294 		 */
1295 		if (IS_GOT_RELATIVE(rsp->rel_rtype)) {
1296 			Ifl_desc	*ifl = rsp->rel_isdesc->is_file;
1297 			Conv_inv_buf_t inv_buf;
1298 
1299 			eprintf(ofl->ofl_lml, ERR_FATAL,
1300 			    MSG_INTL(MSG_REL_PICREDLOC),
1301 			    ld_reloc_sym_name(rsp), ifl->ifl_name,
1302 			    conv_reloc_type(ifl->ifl_ehdr->e_machine,
1303 			    rsp->rel_rtype, 0, &inv_buf));
1304 			return (S_ERROR);
1305 		}
1306 
1307 		/*
1308 		 * Indicate that this relocation should be processed the same
1309 		 * as a section symbol.  For RELA, indicate that the addend
1310 		 * also needs to be applied to this relocation.
1311 		 */
1312 		if ((rsp->rel_flags & FLG_REL_RELA) == FLG_REL_RELA)
1313 			oflags = FLG_REL_SCNNDX | FLG_REL_ADVAL;
1314 		else
1315 			oflags = FLG_REL_SCNNDX;
1316 	}
1317 
1318 	if ((rsp->rel_flags & FLG_REL_RELA) == 0) {
1319 		/*
1320 		 * Intel (Rel) relocations do not contain an addend.  Any
1321 		 * addend is contained within the file at the location
1322 		 * identified by the relocation offset.  Therefore, if we're
1323 		 * processing a section symbol, or a -zredlocsym relocation
1324 		 * (that basically transforms a local symbol reference into
1325 		 * a section reference), perform an active relocation to
1326 		 * propagate any addend.
1327 		 */
1328 		if ((ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION) ||
1329 		    (oflags == FLG_REL_SCNNDX))
1330 			if (ld_add_actrel(NULL, rsp, ofl) == S_ERROR)
1331 				return (S_ERROR);
1332 	}
1333 	return ((*ld_targ.t_mr.mr_add_outrel)(oflags, rsp, ofl));
1334 }
1335 
1336 /*
1337  * Perform any generic TLS validations before passing control to machine
1338  * specific routines.  At this point we know we are dealing with an executable
1339  * or shared object - relocatable objects have already been processed.
1340  */
1341 static uintptr_t
1342 reloc_TLS(Boolean local, Rel_desc *rsp, Ofl_desc *ofl)
1343 {
1344 	Word		rtype = rsp->rel_rtype;
1345 	ofl_flag_t	flags = ofl->ofl_flags;
1346 	Ifl_desc	*ifl = rsp->rel_isdesc->is_file;
1347 	Half		mach = ifl->ifl_ehdr->e_machine;
1348 	Sym_desc	*sdp = rsp->rel_sym;
1349 	unsigned char	type;
1350 	Conv_inv_buf_t	inv_buf1, inv_buf2;
1351 
1352 	/*
1353 	 * All TLS relocations are illegal in a static executable.
1354 	 */
1355 	if (OFL_IS_STATIC_EXEC(ofl)) {
1356 		eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_REL_TLSSTAT),
1357 		    conv_reloc_type(mach, rtype, 0, &inv_buf1), ifl->ifl_name,
1358 		    ld_reloc_sym_name(rsp));
1359 		return (S_ERROR);
1360 	}
1361 
1362 	/*
1363 	 * Any TLS relocation must be against a STT_TLS symbol, all others
1364 	 * are illegal.
1365 	 */
1366 	if ((type = ELF_ST_TYPE(sdp->sd_sym->st_info)) != STT_TLS) {
1367 		eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_REL_TLSBADSYM),
1368 		    conv_reloc_type(mach, rtype, 0, &inv_buf1), ifl->ifl_name,
1369 		    ld_reloc_sym_name(rsp),
1370 		    conv_sym_info_type(mach, type, 0, &inv_buf2));
1371 		return (S_ERROR);
1372 	}
1373 
1374 	/*
1375 	 * A dynamic executable can not use the LD or LE reference models to
1376 	 * reference an external symbol.  A shared object can not use the LD
1377 	 * reference model to reference an external symbol.
1378 	 */
1379 	if (!local && (IS_TLS_LD(rtype) ||
1380 	    ((flags & FLG_OF_EXEC) && IS_TLS_LE(rtype)))) {
1381 		eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_REL_TLSBND),
1382 		    conv_reloc_type(mach, rtype, 0, &inv_buf1), ifl->ifl_name,
1383 		    ld_reloc_sym_name(rsp), sdp->sd_file->ifl_name);
1384 		return (S_ERROR);
1385 	}
1386 
1387 	/*
1388 	 * The TLS LE model is only allowed for dynamic executables.  The TLS IE
1389 	 * model is allowed for shared objects, but this model has restrictions.
1390 	 * This model can only be used freely in dependencies that are loaded
1391 	 * immediately as part of process initialization.  However, during the
1392 	 * initial runtime handshake with libc that establishes the thread
1393 	 * pointer, a small backup TLS reservation is created.  This area can
1394 	 * be used by objects that are loaded after threads are initialized.
1395 	 * However, this area is limited in size and may have already been
1396 	 * used.  This area is intended for specialized applications, and does
1397 	 * not provide the degree of flexibility dynamic TLS can offer.  Under
1398 	 * -z verbose indicate this restriction to the user.
1399 	 */
1400 	if ((flags & FLG_OF_EXEC) == 0) {
1401 		if (IS_TLS_LE(rtype)) {
1402 			eprintf(ofl->ofl_lml, ERR_FATAL,
1403 			    MSG_INTL(MSG_REL_TLSLE),
1404 			    conv_reloc_type(mach, rtype, 0, &inv_buf1),
1405 			    ifl->ifl_name, ld_reloc_sym_name(rsp));
1406 			return (S_ERROR);
1407 
1408 		} else if ((IS_TLS_IE(rtype)) &&
1409 		    (flags & FLG_OF_VERBOSE)) {
1410 			eprintf(ofl->ofl_lml, ERR_WARNING,
1411 			    MSG_INTL(MSG_REL_TLSIE),
1412 			    conv_reloc_type(mach, rtype, 0, &inv_buf1),
1413 			    ifl->ifl_name, ld_reloc_sym_name(rsp));
1414 		}
1415 	}
1416 
1417 	return ((*ld_targ.t_mr.mr_reloc_TLS)(local, rsp, ofl));
1418 }
1419 
1420 uintptr_t
1421 ld_process_sym_reloc(Ofl_desc *ofl, Rel_desc *reld, Rel *reloc, Is_desc *isp,
1422     const char *isname, Word isscnndx)
1423 {
1424 	Word		rtype = reld->rel_rtype;
1425 	ofl_flag_t	flags = ofl->ofl_flags;
1426 	Sym_desc	*sdp = reld->rel_sym;
1427 	Sym_aux		*sap;
1428 	Boolean		local;
1429 	Conv_inv_buf_t	inv_buf;
1430 
1431 	DBG_CALL(Dbg_reloc_in(ofl->ofl_lml, ELF_DBG_LD, ld_targ.t_m.m_mach,
1432 	    ld_targ.t_m.m_rel_sht_type, (void *)reloc, isname, isscnndx,
1433 	    ld_reloc_sym_name(reld)));
1434 
1435 	/*
1436 	 * Indicate this symbol is being used for relocation and therefore must
1437 	 * have its output address updated accordingly (refer to update_osym()).
1438 	 */
1439 	sdp->sd_flags |= FLG_SY_UPREQD;
1440 
1441 	/*
1442 	 * Indicate the section this symbol is defined in has been referenced,
1443 	 * therefor it *is not* a candidate for elimination.
1444 	 */
1445 	if (sdp->sd_isc) {
1446 		sdp->sd_isc->is_flags |= FLG_IS_SECTREF;
1447 		sdp->sd_isc->is_file->ifl_flags |= FLG_IF_FILEREF;
1448 	}
1449 
1450 	if (!ld_reloc_set_aux_usym(ofl, reld, sdp))
1451 		return (S_ERROR);
1452 
1453 	/*
1454 	 * Determine if this symbol is actually an alias to another symbol.  If
1455 	 * so, and the alias is not REF_DYN_SEEN, set ra_usym to point to the
1456 	 * weak symbols strong counter-part.  The one exception is if the
1457 	 * FLG_SY_MVTOCOMM flag is set on the weak symbol.  If this is the case,
1458 	 * the strong is only here because of its promotion, and the weak symbol
1459 	 * should still be used for the relocation reference (see reloc_exec()).
1460 	 */
1461 	sap = sdp->sd_aux;
1462 	if (sap && sap->sa_linkndx &&
1463 	    ((ELF_ST_BIND(sdp->sd_sym->st_info) == STB_WEAK) ||
1464 	    (sdp->sd_flags & FLG_SY_WEAKDEF)) &&
1465 	    (!(sdp->sd_flags & FLG_SY_MVTOCOMM))) {
1466 		Sym_desc	*_sdp;
1467 
1468 		_sdp = sdp->sd_file->ifl_oldndx[sap->sa_linkndx];
1469 		if ((_sdp->sd_ref != REF_DYN_SEEN) &&
1470 		    !ld_reloc_set_aux_usym(ofl, reld, _sdp))
1471 			return (S_ERROR);
1472 	}
1473 
1474 	/*
1475 	 * Determine whether this symbol should be bound locally or not.
1476 	 * Symbols are bound locally if one of the following is true:
1477 	 *
1478 	 *  -	the symbol is of type STB_LOCAL.
1479 	 *
1480 	 *  -	the output image is not a relocatable object and the relocation
1481 	 *	is relative to the .got.
1482 	 *
1483 	 *  -	the section being relocated is of type SHT_SUNW_dof.  These
1484 	 *	sections must be bound to the functions in the containing
1485 	 *	object and can not be interposed upon.
1486 	 *
1487 	 *  -	the symbol has been reduced (scoped to a local or symbolic) and
1488 	 *	reductions are being processed.
1489 	 *
1490 	 *  -	the -Bsymbolic flag is in use when building a shared object,
1491 	 *	and the symbol hasn't explicitly been defined as nodirect.
1492 	 *
1493 	 *  -	an executable (fixed address) is being created, and the symbol
1494 	 *	is defined in the executable.
1495 	 *
1496 	 *  -	the relocation is against a segment which will not be loaded
1497 	 *	into memory.  In this case, the relocation must be resolved
1498 	 *	now, as ld.so.1 can not process relocations against unmapped
1499 	 *	segments.
1500 	 */
1501 	local = FALSE;
1502 	if (ELF_ST_BIND(sdp->sd_sym->st_info) == STB_LOCAL) {
1503 		local = TRUE;
1504 	} else if (!(reld->rel_flags & FLG_REL_LOAD)) {
1505 		local = TRUE;
1506 	} else if (sdp->sd_sym->st_shndx != SHN_UNDEF) {
1507 		if (reld->rel_isdesc &&
1508 		    reld->rel_isdesc->is_shdr->sh_type == SHT_SUNW_dof) {
1509 			local = TRUE;
1510 		} else if (!(flags & FLG_OF_RELOBJ) &&
1511 		    (IS_LOCALBND(rtype) || IS_SEG_RELATIVE(rtype))) {
1512 			local = TRUE;
1513 		} else if ((sdp->sd_ref == REF_REL_NEED) &&
1514 		    ((sdp->sd_flags & FLG_SY_CAP) == 0)) {
1515 			/*
1516 			 * Global symbols may have been individually reduced in
1517 			 * scope.  If the whole object is to be self contained,
1518 			 * such as when generating an executable or a symbolic
1519 			 * shared object, make sure all relocation symbol
1520 			 * references (sections too) are treated locally.  Note,
1521 			 * explicit no-direct symbols should not be bound to
1522 			 * locally.
1523 			 */
1524 			if ((sdp->sd_flags &
1525 			    (FLG_SY_HIDDEN | FLG_SY_PROTECT)))
1526 				local = TRUE;
1527 			else if ((flags & FLG_OF_EXEC) ||
1528 			    ((flags & FLG_OF_SYMBOLIC) &&
1529 			    ((sdp->sd_flags & FLG_SY_NDIR) == 0))) {
1530 				local = TRUE;
1531 			}
1532 		}
1533 	}
1534 
1535 	/*
1536 	 * If this is a PC_RELATIVE relocation, the relocation could be
1537 	 * compromised if the relocated address is later used as a copy
1538 	 * relocated symbol (PSARC 1999/636, bugid 4187211).  Scan the input
1539 	 * files symbol table to cross reference this relocation offset.
1540 	 */
1541 	if ((ofl->ofl_flags & FLG_OF_SHAROBJ) &&
1542 	    IS_PC_RELATIVE(rtype) &&
1543 	    (IS_GOT_PC(rtype) == 0) &&
1544 	    (IS_PLT(rtype) == 0)) {
1545 		if (disp_inspect(ofl, reld, local) == S_ERROR)
1546 			return (S_ERROR);
1547 	}
1548 
1549 	/*
1550 	 * GOT based relocations must bind to the object being built - since
1551 	 * they are relevant to the current GOT.  If not building a relocatable
1552 	 * object - give a appropriate error message.
1553 	 */
1554 	if (!local && !(flags & FLG_OF_RELOBJ) &&
1555 	    IS_GOT_BASED(rtype)) {
1556 		Ifl_desc	*ifl = reld->rel_isdesc->is_file;
1557 
1558 		eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_REL_BADGOTBASED),
1559 		    conv_reloc_type(ifl->ifl_ehdr->e_machine, rtype,
1560 		    0, &inv_buf), ifl->ifl_name, demangle(sdp->sd_name));
1561 		return (S_ERROR);
1562 	}
1563 
1564 	/*
1565 	 * TLS symbols can only have TLS relocations.
1566 	 */
1567 	if ((ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_TLS) &&
1568 	    (IS_TLS_INS(rtype) == 0)) {
1569 		/*
1570 		 * The above test is relaxed if the target section is
1571 		 * non-allocable.
1572 		 */
1573 		if (RELAUX_GET_OSDESC(reld)->os_shdr->sh_flags & SHF_ALLOC) {
1574 			Ifl_desc	*ifl = reld->rel_isdesc->is_file;
1575 
1576 			eprintf(ofl->ofl_lml, ERR_FATAL,
1577 			    MSG_INTL(MSG_REL_BADTLS),
1578 			    conv_reloc_type(ifl->ifl_ehdr->e_machine,
1579 			    rtype, 0, &inv_buf), ifl->ifl_name,
1580 			    demangle(sdp->sd_name));
1581 			return (S_ERROR);
1582 		}
1583 	}
1584 
1585 	/*
1586 	 * Select the relocation to perform.
1587 	 */
1588 	if (IS_REGISTER(rtype)) {
1589 		if (ld_targ.t_mr.mr_reloc_register == NULL) {
1590 			eprintf(ofl->ofl_lml, ERR_FATAL,
1591 			    MSG_INTL(MSG_REL_NOREG));
1592 			return (S_ERROR);
1593 		}
1594 		return ((*ld_targ.t_mr.mr_reloc_register)(reld, isp, ofl));
1595 	}
1596 
1597 	if (flags & FLG_OF_RELOBJ)
1598 		return (reloc_relobj(local, reld, ofl));
1599 
1600 	if (IS_TLS_INS(rtype))
1601 		return (reloc_TLS(local, reld, ofl));
1602 
1603 	if (IS_GOT_OPINS(rtype)) {
1604 		if (ld_targ.t_mr.mr_reloc_GOTOP == NULL) {
1605 			assert(0);
1606 			return (S_ERROR);
1607 		}
1608 		return ((*ld_targ.t_mr.mr_reloc_GOTOP)(local, reld, ofl));
1609 	}
1610 
1611 	if (IS_GOT_RELATIVE(rtype))
1612 		return (ld_reloc_GOT_relative(local, reld, ofl));
1613 
1614 	if (local)
1615 		return ((*ld_targ.t_mr.mr_reloc_local)(reld, ofl));
1616 
1617 	if ((IS_PLT(rtype) || ((sdp->sd_flags & FLG_SY_CAP) &&
1618 	    (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_FUNC))) &&
1619 	    ((flags & FLG_OF_BFLAG) == 0))
1620 		return (ld_reloc_plt(reld, ofl));
1621 
1622 	if ((sdp->sd_ref == REF_REL_NEED) ||
1623 	    (flags & FLG_OF_BFLAG) || (flags & FLG_OF_SHAROBJ) ||
1624 	    (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_NOTYPE))
1625 		return ((*ld_targ.t_mr.mr_add_outrel)(NULL, reld, ofl));
1626 
1627 	if (sdp->sd_ref == REF_DYN_NEED)
1628 		return (reloc_exec(reld, ofl));
1629 
1630 	/*
1631 	 * IS_NOT_REL(rtype)
1632 	 */
1633 	return (reloc_generic(reld, ofl));
1634 }
1635 
1636 /*
1637  * Given a relocation that references a local symbol from a discarded COMDAT
1638  * section, replace the symbol with the corresponding symbol from the section
1639  * that was kept.
1640  *
1641  * entry:
1642  *	reld - Relocation
1643  *	sdp - Symbol to be replaced. Must be a local symbol (STB_LOCAL).
1644  *	reject - Address of variable to receive rejection code
1645  *		if no replacement symbol is found.
1646  *
1647  * exit:
1648  *	Returns address of replacement symbol descriptor if one was
1649  *	found, and NULL otherwise. The result is also cached in
1650  *	ofl->ofl_sr_cache as an optimization to speed following calls
1651  *	for the same value of sdp.
1652  *
1653  *	On success (non-NULL result), *reject is set to RLXREL_REJ_NONE.
1654  *	On failure (NULL result), *reject is filled in with a code
1655  *	describing the underlying reason.
1656  *
1657  * note:
1658  *	The word "COMDAT" is used to refer to actual COMDAT sections, COMDAT
1659  *	groups tied together with an SHF_GROUP section, and .gnu.linkonce
1660  *	sections which provide a simplified COMDAT requirement.  COMDAT
1661  *	sections are identified with the FLG_IS_COMDAT section flag.
1662  *
1663  *	In principle, this sort of sloppy relocation remapping is
1664  *	a questionable practice. All self-referential sections should
1665  *	be in a common SHF_GROUP so that they are all kept or removed
1666  *	together. The problem is that there is no way to ensure that the
1667  *	two sections are similar enough that the replacement section will
1668  *	really supply the correct information. However, we see a couple of
1669  *	situations where it is useful to do this: (1) Older Sun C compilers
1670  *	generated DWARF sections that would refer to one of the COMDAT
1671  *	sections, and (2) gcc, when its GNU linkonce COMDAT feature is enabled.
1672  *	It turns out that the GNU ld does these sloppy remappings.
1673  *
1674  *	The GNU ld takes an approach that hard wires special section
1675  *	names and treats them specially. We avoid that practice and
1676  *	try to get the necessary work done relying only on the ELF
1677  *	attributes of the sections and symbols involved. This means
1678  *	that our heuristic is somewhat different than theirs, but the
1679  *	end result is close enough to solve the same problem.
1680  *
1681  *	gcc is in the process of converting to SHF_GROUP. This will
1682  *	eventually phase out the need for sloppy relocations, and
1683  *	then this logic won't be needed. In the meantime, relaxed relocation
1684  *	processing allows us to interoperate.
1685  */
1686 static Sym_desc *
1687 sloppy_comdat_reloc(Ofl_desc *ofl, Rel_desc *reld, Sym_desc *sdp,
1688     Rlxrel_rej *reject)
1689 {
1690 	Is_desc		*rep_isp;
1691 	Sym		*sym, *rep_sym;
1692 	Is_desc		*isp;
1693 	Ifl_desc	*ifl;
1694 	Conv_inv_buf_t	inv_buf;
1695 	Word		scnndx, symscnt;
1696 	Sym_desc	**oldndx, *rep_sdp;
1697 	const char	*is_name;
1698 
1699 
1700 	/*
1701 	 * Sloppy relocations are never applied to .eh_frame or
1702 	 * .gcc_except_table sections. The entries in these sections
1703 	 * for discarded sections are better left uninitialized.
1704 	 *
1705 	 * We match these sections by name, because on most platforms they
1706 	 * are SHT_PROGBITS, and cannot be identified otherwise. On amd64
1707 	 * architectures, .eh_frame is SHT_AMD64_UNWIND, but that is ambiguous
1708 	 * (.eh_frame_hdr is also SHT_AMD64_UNWIND), so we still match it by
1709 	 * name.
1710 	 */
1711 	is_name = reld->rel_isdesc->is_name;
1712 	if (((is_name[1] == 'e') &&
1713 	    (strcmp(is_name, MSG_ORIG(MSG_SCN_EHFRAME)) == 0)) ||
1714 	    ((is_name[1] == 'g') &&
1715 	    (strcmp(is_name, MSG_ORIG(MSG_SCN_GCC_X_TBL)) == 0))) {
1716 		*reject = RLXREL_REJ_TARGET;
1717 		return (NULL);
1718 	}
1719 
1720 	/*
1721 	 * If we looked up the same symbol on the previous call, we can
1722 	 * return the cached value.
1723 	 */
1724 	if (sdp == ofl->ofl_sr_cache.sr_osdp) {
1725 		*reject = ofl->ofl_sr_cache.sr_rej;
1726 		return (ofl->ofl_sr_cache.sr_rsdp);
1727 	}
1728 
1729 	ofl->ofl_sr_cache.sr_osdp = sdp;
1730 	sym = sdp->sd_sym;
1731 	isp = sdp->sd_isc;
1732 	ifl = sdp->sd_file;
1733 
1734 	/*
1735 	 * When a COMDAT section is discarded in favor of another COMDAT
1736 	 * section, the replacement is recorded in its section descriptor
1737 	 * (is_comdatkeep). We must validate the replacement before using
1738 	 * it. The replacement section must:
1739 	 *	- Not have been discarded
1740 	 *	- Have the same size (*)
1741 	 *	- Have the same section type
1742 	 *	- Have the same SHF_GROUP flag setting (either on or off)
1743 	 *	- Must be a COMDAT section of one form or the other.
1744 	 *
1745 	 * (*) One might imagine that the replacement section could be
1746 	 * larger than the original, rather than the exact size. However,
1747 	 * we have verified that this is the same policy used by the GNU
1748 	 * ld. If the sections are not the same size, the chance of them
1749 	 * being interchangeable drops significantly.
1750 	 */
1751 	if (((rep_isp = isp->is_comdatkeep) == NULL) ||
1752 	    ((rep_isp->is_flags & FLG_IS_DISCARD) != 0) ||
1753 	    ((rep_isp->is_flags & FLG_IS_COMDAT) == 0) ||
1754 	    (isp->is_indata->d_size != rep_isp->is_indata->d_size) ||
1755 	    (isp->is_shdr->sh_type != rep_isp->is_shdr->sh_type) ||
1756 	    ((isp->is_shdr->sh_flags & SHF_GROUP) !=
1757 	    (rep_isp->is_shdr->sh_flags & SHF_GROUP))) {
1758 		*reject = ofl->ofl_sr_cache.sr_rej = RLXREL_REJ_SECTION;
1759 		return (ofl->ofl_sr_cache.sr_rsdp = NULL);
1760 	}
1761 
1762 	/*
1763 	 * We found the kept COMDAT section. Now, look at all of the
1764 	 * symbols from the input file that contains it to find the
1765 	 * symbol that corresponds to the one we started with:
1766 	 *	- Hasn't been discarded
1767 	 *	- Has section index of kept section
1768 	 *	- If one symbol has a name, the other must have
1769 	 *		the same name. The st_name field of a symbol
1770 	 *		is 0 if there is no name, and is a string
1771 	 *		table offset otherwise. The string table
1772 	 *		offsets may well not agree --- it is the
1773 	 *		actual string that matters.
1774 	 *	- Type and binding attributes match (st_info)
1775 	 *	- Values match (st_value)
1776 	 *	- Sizes match (st_size)
1777 	 *	- Visibility matches (st_other)
1778 	 */
1779 	scnndx = rep_isp->is_scnndx;
1780 	oldndx = rep_isp->is_file->ifl_oldndx;
1781 	symscnt = rep_isp->is_file->ifl_symscnt;
1782 	while (symscnt--) {
1783 		rep_sdp = *oldndx++;
1784 		if ((rep_sdp == NULL) || (rep_sdp->sd_flags & FLG_SY_ISDISC) ||
1785 		    ((rep_sym = rep_sdp->sd_sym)->st_shndx != scnndx) ||
1786 		    ((sym->st_name == 0) != (rep_sym->st_name == 0)) ||
1787 		    ((sym->st_name != 0) &&
1788 		    (strcmp(sdp->sd_name, rep_sdp->sd_name) != 0)) ||
1789 		    (sym->st_info != rep_sym->st_info) ||
1790 		    (sym->st_value != rep_sym->st_value) ||
1791 		    (sym->st_size != rep_sym->st_size) ||
1792 		    (sym->st_other != rep_sym->st_other))
1793 			continue;
1794 
1795 
1796 		if (ofl->ofl_flags & FLG_OF_VERBOSE) {
1797 			if (sym->st_name != 0) {
1798 				eprintf(ofl->ofl_lml, ERR_WARNING,
1799 				    MSG_INTL(MSG_REL_SLOPCDATNAM),
1800 				    conv_reloc_type(ifl->ifl_ehdr->e_machine,
1801 				    reld->rel_rtype, 0, &inv_buf),
1802 				    ifl->ifl_name,
1803 				    EC_WORD(reld->rel_isdesc->is_scnndx),
1804 				    reld->rel_isdesc->is_name,
1805 				    rep_sdp->sd_name,
1806 				    EC_WORD(isp->is_scnndx), isp->is_name,
1807 				    rep_sdp->sd_file->ifl_name);
1808 			} else {
1809 				eprintf(ofl->ofl_lml, ERR_WARNING,
1810 				    MSG_INTL(MSG_REL_SLOPCDATNONAM),
1811 				    conv_reloc_type(ifl->ifl_ehdr->e_machine,
1812 				    reld->rel_rtype, 0, &inv_buf),
1813 				    ifl->ifl_name,
1814 				    EC_WORD(reld->rel_isdesc->is_scnndx),
1815 				    reld->rel_isdesc->is_name,
1816 				    EC_WORD(isp->is_scnndx), isp->is_name,
1817 				    rep_sdp->sd_file->ifl_name);
1818 			}
1819 		}
1820 		DBG_CALL(Dbg_reloc_sloppycomdat(ofl->ofl_lml, rep_sdp));
1821 		*reject = ofl->ofl_sr_cache.sr_rej = RLXREL_REJ_NONE;
1822 		return (ofl->ofl_sr_cache.sr_rsdp = rep_sdp);
1823 	}
1824 
1825 	/* If didn't return above, we didn't find it */
1826 	*reject = ofl->ofl_sr_cache.sr_rej = RLXREL_REJ_SYMBOL;
1827 	return (ofl->ofl_sr_cache.sr_rsdp = NULL);
1828 }
1829 
1830 /*
1831  * Generate relocation descriptor and dispatch
1832  */
1833 static uintptr_t
1834 process_reld(Ofl_desc *ofl, Is_desc *isp, Rel_desc *reld, Word rsndx,
1835     Rel *reloc)
1836 {
1837 	Ifl_desc	*ifl = isp->is_file;
1838 	Word		rtype = reld->rel_rtype;
1839 	Sym_desc	*sdp;
1840 	Conv_inv_buf_t	inv_buf;
1841 
1842 	/*
1843 	 * Make sure the relocation is in the valid range.
1844 	 */
1845 	if (rtype >= ld_targ.t_m.m_r_num) {
1846 		eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_REL_INVALRELT),
1847 		    ifl->ifl_name, EC_WORD(isp->is_scnndx), isp->is_name,
1848 		    rtype);
1849 		return (S_ERROR);
1850 	}
1851 
1852 	ofl->ofl_entrelscnt++;
1853 
1854 	/*
1855 	 * Special case: a register symbol associated with symbol index 0 is
1856 	 * initialized (i.e., relocated) to a constant from the r_addend field
1857 	 * rather than from a symbol value.
1858 	 */
1859 	if (IS_REGISTER(rtype) && (rsndx == 0)) {
1860 		reld->rel_sym = NULL;
1861 		DBG_CALL(Dbg_reloc_in(ofl->ofl_lml, ELF_DBG_LD,
1862 		    ld_targ.t_m.m_mach, isp->is_shdr->sh_type,
1863 		    (void *)reloc, isp->is_name, isp->is_scnndx,
1864 		    ld_reloc_sym_name(reld)));
1865 		if (ld_targ.t_mr.mr_reloc_register == NULL) {
1866 			eprintf(ofl->ofl_lml, ERR_FATAL,
1867 			    MSG_INTL(MSG_REL_NOREG));
1868 			return (S_ERROR);
1869 		}
1870 		return ((*ld_targ.t_mr.mr_reloc_register)(reld, isp, ofl));
1871 	}
1872 
1873 	/*
1874 	 * If this is a STT_SECTION symbol, make sure the associated
1875 	 * section has a descriptive non-NULL is_sym_name field that can
1876 	 * be accessed by ld_reloc_sym_name() to satisfy debugging output
1877 	 * and errors.
1878 	 *
1879 	 * In principle, we could add this string to every input section
1880 	 * as it is created, but we defer it until we see a relocation
1881 	 * symbol that might need it. Not every section will have such
1882 	 * a relocation, so we create fewer of them this way.
1883 	 */
1884 	sdp = reld->rel_sym = ifl->ifl_oldndx[rsndx];
1885 	if ((sdp != NULL) &&
1886 	    (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION) &&
1887 	    (sdp->sd_isc != NULL) && (sdp->sd_isc->is_name != NULL) &&
1888 	    (sdp->sd_isc->is_sym_name == NULL) &&
1889 	    (ld_stt_section_sym_name(sdp->sd_isc) == NULL))
1890 		return (S_ERROR);
1891 
1892 	/*
1893 	 * If for some reason we have a null relocation record issue a
1894 	 * warning and continue (the compiler folks can get into this
1895 	 * state some time).  Normal users should never see this error.
1896 	 */
1897 	if (rtype == ld_targ.t_m.m_r_none) {
1898 		DBG_CALL(Dbg_reloc_in(ofl->ofl_lml, ELF_DBG_LD,
1899 		    ld_targ.t_m.m_mach, ld_targ.t_m.m_rel_sht_type,
1900 		    (void *)reloc, isp->is_name, isp->is_scnndx,
1901 		    ld_reloc_sym_name(reld)));
1902 		eprintf(ofl->ofl_lml, ERR_WARNING, MSG_INTL(MSG_REL_NULL),
1903 		    ifl->ifl_name, EC_WORD(isp->is_scnndx), isp->is_name);
1904 		return (1);
1905 	}
1906 
1907 	if (((ofl->ofl_flags & FLG_OF_RELOBJ) == 0) &&
1908 	    IS_NOTSUP(rtype)) {
1909 		eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_REL_NOTSUP),
1910 		    conv_reloc_type(ifl->ifl_ehdr->e_machine, rtype,
1911 		    0, &inv_buf), ifl->ifl_name, EC_WORD(isp->is_scnndx),
1912 		    isp->is_name);
1913 		return (S_ERROR);
1914 	}
1915 
1916 	/*
1917 	 * If we are here, we know that the relocation requires reference
1918 	 * symbol. If no symbol is assigned, this is a fatal error.
1919 	 */
1920 	if (sdp == NULL) {
1921 		eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_REL_NOSYMBOL),
1922 		    conv_reloc_type(ifl->ifl_ehdr->e_machine, rtype,
1923 		    0, &inv_buf), ifl->ifl_name, EC_WORD(isp->is_scnndx),
1924 		    isp->is_name, EC_XWORD(reloc->r_offset));
1925 		return (S_ERROR);
1926 	}
1927 
1928 	if (sdp->sd_flags & FLG_SY_IGNORE)
1929 		return (1);
1930 
1931 	/*
1932 	 * If this symbol is part of a DISCARDED section attempt to find another
1933 	 * definition.
1934 	 */
1935 	if (sdp->sd_flags & FLG_SY_ISDISC) {
1936 		Sym_desc	*nsdp = NULL;
1937 		Rlxrel_rej	reject;
1938 
1939 		if (ELF_ST_BIND(sdp->sd_sym->st_info) == STB_LOCAL) {
1940 			/*
1941 			 * If "-z relaxreloc", and the input section is COMDAT
1942 			 * that has been assigned to an output section, then
1943 			 * determine if this is a reference to a discarded
1944 			 * COMDAT section that can be replaced with a COMDAT
1945 			 * that has been kept.
1946 			 */
1947 			if ((ofl->ofl_flags1 & FLG_OF1_RLXREL) &&
1948 			    sdp->sd_isc->is_osdesc &&
1949 			    (sdp->sd_isc->is_flags & FLG_IS_COMDAT) &&
1950 			    ((nsdp = sloppy_comdat_reloc(ofl, reld,
1951 			    sdp, &reject)) == NULL)) {
1952 				Shdr	*is_shdr = reld->rel_isdesc->is_shdr;
1953 
1954 				/*
1955 				 * A matching symbol was not found. We will
1956 				 * ignore this relocation.  Determine whether
1957 				 * or not to issue a warning.
1958 				 * Warnings are always issued under -z verbose,
1959 				 * but otherwise, we will follow the lead of
1960 				 * the GNU ld and suppress them for certain
1961 				 * cases:
1962 				 *
1963 				 *  -	It is a non-allocable debug section.
1964 				 *	The GNU ld tests for these by name,
1965 				 *	but we are willing to extend it to
1966 				 *	any non-allocable section.
1967 				 *  -	The target section is excluded from
1968 				 *	sloppy relocations by policy.
1969 				 */
1970 				if (((ofl->ofl_flags & FLG_OF_VERBOSE) != 0) ||
1971 				    ((is_shdr->sh_flags & SHF_ALLOC) &&
1972 				    (reject != RLXREL_REJ_TARGET)))
1973 					eprintf(ofl->ofl_lml, ERR_WARNING,
1974 					    MSG_INTL(MSG_REL_SLOPCDATNOSYM),
1975 					    conv_reloc_type(
1976 					    ifl->ifl_ehdr->e_machine,
1977 					    reld->rel_rtype, 0, &inv_buf),
1978 					    ifl->ifl_name,
1979 					    EC_WORD(isp->is_scnndx),
1980 					    isp->is_name,
1981 					    ld_reloc_sym_name(reld),
1982 					    EC_WORD(sdp->sd_isc->is_scnndx),
1983 					    sdp->sd_isc->is_name);
1984 				return (1);
1985 			}
1986 		} else if ((sdp != NULL) && sdp->sd_name && *sdp->sd_name)
1987 			nsdp = ld_sym_find(sdp->sd_name, SYM_NOHASH, NULL, ofl);
1988 
1989 		if (nsdp == NULL) {
1990 			eprintf(ofl->ofl_lml, ERR_FATAL,
1991 			    MSG_INTL(MSG_REL_SYMDISC),
1992 			    conv_reloc_type(ifl->ifl_ehdr->e_machine,
1993 			    reld->rel_rtype, 0, &inv_buf), ifl->ifl_name,
1994 			    EC_WORD(isp->is_scnndx), isp->is_name,
1995 			    ld_reloc_sym_name(reld),
1996 			    EC_WORD(sdp->sd_isc->is_scnndx),
1997 			    sdp->sd_isc->is_name);
1998 			return (S_ERROR);
1999 		}
2000 		ifl->ifl_oldndx[rsndx] = sdp = nsdp;
2001 		if ((ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION) &&
2002 		    (sdp->sd_isc != NULL) && (sdp->sd_isc->is_name != NULL) &&
2003 		    (sdp->sd_isc->is_sym_name == NULL) &&
2004 		    (ld_stt_section_sym_name(sdp->sd_isc) == NULL))
2005 			return (S_ERROR);
2006 	}
2007 
2008 	/*
2009 	 * If this is a global symbol, determine whether its visibility needs
2010 	 * adjusting.
2011 	 */
2012 	if (sdp->sd_aux && ((sdp->sd_flags & FLG_SY_VISIBLE) == 0))
2013 		ld_sym_adjust_vis(sdp, ofl);
2014 
2015 	/*
2016 	 * Ignore any relocation against a section that will not be in the
2017 	 * output file (has been stripped).
2018 	 */
2019 	if ((sdp->sd_isc == 0) &&
2020 	    (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION))
2021 		return (1);
2022 
2023 	/*
2024 	 * If the input section exists, but the section has not been associated
2025 	 * to an output section, then this is a little suspicious.
2026 	 */
2027 	if (sdp->sd_isc && (sdp->sd_isc->is_osdesc == 0) &&
2028 	    (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION)) {
2029 		eprintf(ofl->ofl_lml, ERR_WARNING, MSG_INTL(MSG_RELINVSEC),
2030 		    conv_reloc_type(ifl->ifl_ehdr->e_machine, rtype,
2031 		    0, &inv_buf), ifl->ifl_name, EC_WORD(isp->is_scnndx),
2032 		    isp->is_name, EC_WORD(sdp->sd_isc->is_scnndx),
2033 		    sdp->sd_isc->is_name);
2034 		return (1);
2035 	}
2036 
2037 	/*
2038 	 * If the symbol for this relocation is invalid (which should have
2039 	 * generated a message during symbol processing), or the relocation
2040 	 * record's symbol reference is in any other way invalid, then it's
2041 	 * about time we gave up.
2042 	 */
2043 	if ((sdp->sd_flags & FLG_SY_INVALID) || (rsndx == 0) ||
2044 	    (rsndx >= ifl->ifl_symscnt)) {
2045 		eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_REL_UNKNWSYM),
2046 		    conv_reloc_type(ifl->ifl_ehdr->e_machine, rtype,
2047 		    0, &inv_buf), ifl->ifl_name, EC_WORD(isp->is_scnndx),
2048 		    isp->is_name, ld_reloc_sym_name(reld),
2049 		    EC_XWORD(reloc->r_offset), EC_WORD(rsndx));
2050 		return (S_ERROR);
2051 	}
2052 
2053 	/*
2054 	 * Size relocations against section symbols are presently unsupported.
2055 	 * There is a question as to whether the input section size, or output
2056 	 * section size would be used.  Until an explicit requirement is
2057 	 * established for either case, we'll punt.
2058 	 */
2059 	if (IS_SIZE(rtype) &&
2060 	    (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION)) {
2061 		eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_REL_UNSUPSIZE),
2062 		    conv_reloc_type(ifl->ifl_ehdr->e_machine, rtype,
2063 		    0, &inv_buf), ifl->ifl_name, EC_WORD(isp->is_scnndx),
2064 		    isp->is_name);
2065 		return (S_ERROR);
2066 	}
2067 
2068 	reld->rel_sym = sdp;
2069 	if (reld->rel_aux)
2070 		reld->rel_aux->ra_usym = sdp;
2071 	return (ld_process_sym_reloc(ofl, reld, reloc, isp, isp->is_name,
2072 	    isp->is_scnndx));
2073 }
2074 
2075 static uintptr_t
2076 reloc_section(Ofl_desc *ofl, Is_desc *isect, Is_desc *rsect, Os_desc *osect)
2077 {
2078 	Rel		*rend;		/* end of relocation section data */
2079 	Rel		*reloc;		/* current relocation entry */
2080 	Xword		rsize;		/* size of relocation section data */
2081 	Xword		entsize;	/* size of relocation entry */
2082 	Rel_desc	reld;		/* relocation descriptor */
2083 	Rel_aux	rel_aux;
2084 	Shdr *		shdr;
2085 	Word		flags = 0;
2086 	uintptr_t	ret = 1;
2087 
2088 	shdr = rsect->is_shdr;
2089 	rsize = shdr->sh_size;
2090 	reloc = (Rel *)rsect->is_indata->d_buf;
2091 
2092 	/*
2093 	 * Decide entry size.
2094 	 */
2095 	if (((entsize = shdr->sh_entsize) == 0) || (entsize > rsize)) {
2096 		if (shdr->sh_type == SHT_RELA)
2097 			entsize = sizeof (Rela);
2098 		else
2099 			entsize = sizeof (Rel);
2100 	}
2101 
2102 	/*
2103 	 * Build up the basic information in for the Rel_desc structure.
2104 	 */
2105 	reld.rel_isdesc = isect;
2106 	reld.rel_aux = &rel_aux;
2107 	ld_init_rel_aux(&reld);
2108 	rel_aux.ra_osdesc = osect;
2109 
2110 	if ((ofl->ofl_flags & FLG_OF_RELOBJ) ||
2111 	    (osect && (osect->os_sgdesc->sg_phdr.p_type == PT_LOAD)))
2112 		flags |= FLG_REL_LOAD;
2113 
2114 	if (shdr->sh_info == 0)
2115 		flags |= FLG_REL_NOINFO;
2116 
2117 	DBG_CALL(Dbg_reloc_proc(ofl->ofl_lml, osect, isect, rsect));
2118 
2119 	for (rend = (Rel *)((uintptr_t)reloc + (uintptr_t)rsize);
2120 	    reloc < rend;
2121 	    reloc = (Rel *)((uintptr_t)reloc + (uintptr_t)entsize)) {
2122 		Word	rsndx;
2123 
2124 		/*
2125 		 * Initialize the relocation record information and process
2126 		 * the individual relocation.  Reinitialize the flags to
2127 		 * insure we don't carry any state over from the previous
2128 		 * relocation records processing.
2129 		 */
2130 		reld.rel_flags = flags;
2131 		rsndx = (*ld_targ.t_mr.mr_init_rel)(&reld,
2132 		    &rel_aux.ra_typedata, (void *)reloc);
2133 
2134 		/*
2135 		 * Determine whether or not to pass an auxiliary block
2136 		 * in with this Rel_desc. It is not needed if both the
2137 		 * osdesc and typedata fields have default values.
2138 		 */
2139 		reld.rel_aux =
2140 		    (RELAUX_ISDEFAULT_OSDESC(&reld, rel_aux.ra_osdesc) &&
2141 		    RELAUX_ISDEFAULT_TYPEDATA(&reld, rel_aux.ra_typedata)) ?
2142 		    NULL : &rel_aux;
2143 
2144 		if (process_reld(ofl, rsect, &reld, rsndx, reloc) == S_ERROR)
2145 			ret = S_ERROR;
2146 	}
2147 	return (ret);
2148 }
2149 
2150 static uintptr_t
2151 reloc_segments(int wr_flag, Ofl_desc *ofl)
2152 {
2153 	Aliste		idx1;
2154 	Sg_desc		*sgp;
2155 	Is_desc		*isp;
2156 
2157 	for (APLIST_TRAVERSE(ofl->ofl_segs, idx1, sgp)) {
2158 		Os_desc	*osp;
2159 		Aliste	idx2;
2160 
2161 		if ((sgp->sg_phdr.p_flags & PF_W) != wr_flag)
2162 			continue;
2163 
2164 		for (APLIST_TRAVERSE(sgp->sg_osdescs, idx2, osp)) {
2165 			Is_desc	*risp;
2166 			Aliste	idx3;
2167 
2168 			osp->os_szoutrels = 0;
2169 			for (APLIST_TRAVERSE(osp->os_relisdescs, idx3, risp)) {
2170 				Word	indx;
2171 
2172 				/*
2173 				 * Determine the input section that this
2174 				 * relocation information refers to.
2175 				 */
2176 				indx = risp->is_shdr->sh_info;
2177 				isp = risp->is_file->ifl_isdesc[indx];
2178 
2179 				/*
2180 				 * Do not process relocations against sections
2181 				 * which are being discarded (COMDAT)
2182 				 */
2183 				if (isp->is_flags & FLG_IS_DISCARD)
2184 					continue;
2185 
2186 				if (reloc_section(ofl, isp, risp, osp) ==
2187 				    S_ERROR)
2188 					return (S_ERROR);
2189 			}
2190 
2191 			/*
2192 			 * Check for relocations against non-writable
2193 			 * allocatable sections.
2194 			 */
2195 			if (osp->os_szoutrels &&
2196 			    (sgp->sg_phdr.p_type == PT_LOAD) &&
2197 			    ((sgp->sg_phdr.p_flags & PF_W) == 0)) {
2198 				ofl->ofl_flags |= FLG_OF_TEXTREL;
2199 				ofl->ofl_dtflags |= DF_TEXTREL;
2200 			}
2201 		}
2202 	}
2203 
2204 	return (1);
2205 }
2206 
2207 /*
2208  * Move Section related function
2209  * Get move entry
2210  */
2211 static Move *
2212 get_move_entry(Is_desc *rsect, Xword roffset)
2213 {
2214 	Ifl_desc	*ifile = rsect->is_file;
2215 	Shdr		*rshdr = rsect->is_shdr;
2216 	Is_desc		*misp;
2217 	Shdr		*mshdr;
2218 	Xword 		midx;
2219 	Move		*mvp;
2220 
2221 	/*
2222 	 * Set info for the target move section
2223 	 */
2224 	misp = ifile->ifl_isdesc[rshdr->sh_info];
2225 	mshdr = misp->is_shdr;
2226 
2227 	if (mshdr->sh_entsize == 0)
2228 		return (NULL);
2229 
2230 	/*
2231 	 * If this is an invalid entry, return NULL.
2232 	 */
2233 	midx = roffset / mshdr->sh_entsize;
2234 	if ((midx * mshdr->sh_entsize) >= mshdr->sh_size)
2235 		return (NULL);
2236 
2237 	mvp = (Move *)misp->is_indata->d_buf;
2238 	mvp += midx;
2239 	return (mvp);
2240 }
2241 
2242 /*
2243  * Relocation against Move Table.
2244  */
2245 static uintptr_t
2246 process_movereloc(Ofl_desc *ofl, Is_desc *rsect)
2247 {
2248 	Ifl_desc	*file = rsect->is_file;
2249 	Rel		*rend, *reloc;
2250 	Xword 		rsize, entsize;
2251 	Rel_desc 	reld;
2252 	Rel_aux	rel_aux;
2253 
2254 	rsize = rsect->is_shdr->sh_size;
2255 	reloc = (Rel *)rsect->is_indata->d_buf;
2256 
2257 	/*
2258 	 * Decide entry size.
2259 	 */
2260 	entsize = rsect->is_shdr->sh_entsize;
2261 	if ((entsize == 0) ||
2262 	    (entsize > rsect->is_shdr->sh_size)) {
2263 		if (rsect->is_shdr->sh_type == SHT_RELA)
2264 			entsize = sizeof (Rela);
2265 		else
2266 			entsize = sizeof (Rel);
2267 	}
2268 
2269 	/*
2270 	 * The requirement for move data ensures that we have to supply a
2271 	 * Rel_aux auxiliary block.
2272 	 */
2273 	reld.rel_aux = &rel_aux;
2274 	ld_init_rel_aux(&reld);
2275 
2276 	/*
2277 	 * Go through the relocation entries.
2278 	 */
2279 	for (rend = (Rel *)((uintptr_t)reloc + (uintptr_t)rsize);
2280 	    reloc < rend;
2281 	    reloc = (Rel *)((uintptr_t)reloc + (uintptr_t)entsize)) {
2282 		Sym_desc	*psdp;
2283 		Move		*mvp;
2284 		Word		rsndx;
2285 
2286 		/*
2287 		 * Initialize the relocation record information.
2288 		 */
2289 		reld.rel_flags = FLG_REL_LOAD;
2290 		rsndx = (*ld_targ.t_mr.mr_init_rel)(&reld,
2291 		    &rel_aux.ra_typedata, (void *)reloc);
2292 
2293 		if (((mvp = get_move_entry(rsect, reloc->r_offset)) == NULL) ||
2294 		    ((rel_aux.ra_move =
2295 		    libld_malloc(sizeof (Mv_reloc))) == NULL))
2296 			return (S_ERROR);
2297 
2298 		psdp = file->ifl_oldndx[ELF_M_SYM(mvp->m_info)];
2299 		rel_aux.ra_move->mr_move = mvp;
2300 		rel_aux.ra_move->mr_sym = psdp;
2301 
2302 		if (psdp->sd_flags & FLG_SY_PAREXPN) {
2303 			int	_num, num = mvp->m_repeat;
2304 
2305 			rel_aux.ra_osdesc = ofl->ofl_isparexpn->is_osdesc;
2306 			reld.rel_isdesc = ofl->ofl_isparexpn;
2307 			reld.rel_roffset = mvp->m_poffset;
2308 
2309 			for (_num = 0; _num < num; _num++) {
2310 				reld.rel_roffset +=
2311 				    /* LINTED */
2312 				    (_num * ELF_M_SIZE(mvp->m_info));
2313 
2314 				/*
2315 				 * Generate Reld
2316 				 */
2317 				if (process_reld(ofl,
2318 				    rsect, &reld, rsndx, reloc) == S_ERROR)
2319 					return (S_ERROR);
2320 			}
2321 		} else {
2322 			/*
2323 			 * Generate Reld
2324 			 */
2325 			reld.rel_flags |= FLG_REL_MOVETAB;
2326 			rel_aux.ra_osdesc = ofl->ofl_osmove;
2327 			reld.rel_isdesc = ld_os_first_isdesc(ofl->ofl_osmove);
2328 
2329 			if (process_reld(ofl,
2330 			    rsect, &reld, rsndx, reloc) == S_ERROR)
2331 				return (S_ERROR);
2332 		}
2333 	}
2334 	return (1);
2335 }
2336 
2337 /*
2338  * This function is similar to reloc_init().
2339  *
2340  * This function is called when the SHT_SUNW_move table is expanded and there
2341  * are relocations against the SHT_SUNW_move section.
2342  */
2343 static uintptr_t
2344 reloc_movesections(Ofl_desc *ofl)
2345 {
2346 	Aliste		idx;
2347 	Is_desc		*risp;
2348 	uintptr_t	ret = 1;
2349 
2350 	/*
2351 	 * Generate/Expand relocation entries
2352 	 */
2353 	for (APLIST_TRAVERSE(ofl->ofl_ismoverel, idx, risp)) {
2354 		if (process_movereloc(ofl, risp) == S_ERROR)
2355 			ret = S_ERROR;
2356 	}
2357 
2358 	return (ret);
2359 }
2360 
2361 /*
2362  * Count the number of output relocation entries, global offset table entries,
2363  * and procedure linkage table entries.  This function searches the segment and
2364  * outsect lists and passes each input reloc section to process_reloc().
2365  * It allocates space for any output relocations needed.  And builds up
2366  * the relocation structures for later processing.
2367  */
2368 uintptr_t
2369 ld_reloc_init(Ofl_desc *ofl)
2370 {
2371 	Aliste		idx;
2372 	Is_desc		*isp;
2373 	Sym_desc	*sdp;
2374 
2375 	DBG_CALL(Dbg_basic_collect(ofl->ofl_lml));
2376 
2377 	/*
2378 	 * At this point we have finished processing all input symbols.  Make
2379 	 * sure we add any absolute (internal) symbols before continuing with
2380 	 * any relocation processing.
2381 	 */
2382 	if (ld_sym_spec(ofl) == S_ERROR)
2383 		return (S_ERROR);
2384 
2385 	ofl->ofl_gotcnt = ld_targ.t_m.m_got_xnumber;
2386 
2387 	/*
2388 	 * Process all of the relocations against NON-writable segments
2389 	 * followed by relocations against the writable segments.
2390 	 *
2391 	 * This separation is so that when the writable segments are processed
2392 	 * we know whether or not a COPYRELOC will be produced for any symbols.
2393 	 * If relocations aren't processed in this order, a COPYRELOC and a
2394 	 * regular relocation can be produced against the same symbol.  The
2395 	 * regular relocation would be redundant.
2396 	 */
2397 	if (reloc_segments(0, ofl) == S_ERROR)
2398 		return (S_ERROR);
2399 
2400 	if (reloc_segments(PF_W, ofl) == S_ERROR)
2401 		return (S_ERROR);
2402 
2403 	/*
2404 	 * Process any extra relocations.  These are relocation sections that
2405 	 * have a NULL sh_info.
2406 	 */
2407 	for (APLIST_TRAVERSE(ofl->ofl_extrarels, idx, isp)) {
2408 		if (reloc_section(ofl, NULL, isp, NULL) == S_ERROR)
2409 			return (S_ERROR);
2410 	}
2411 
2412 	/*
2413 	 * If there were relocation against move table,
2414 	 * process the relocation sections.
2415 	 */
2416 	if (reloc_movesections(ofl) == S_ERROR)
2417 		return (S_ERROR);
2418 
2419 	/*
2420 	 * Now all the relocations are pre-processed,
2421 	 * check the validity of copy relocations.
2422 	 */
2423 	if (ofl->ofl_copyrels) {
2424 		Copy_rel	*crp;
2425 
2426 		for (ALIST_TRAVERSE(ofl->ofl_copyrels, idx, crp)) {
2427 			/*
2428 			 * If there were no displacement relocation
2429 			 * in this file, don't worry about it.
2430 			 */
2431 			if (crp->c_sdp->sd_file->ifl_flags &
2432 			    (FLG_IF_DISPPEND | FLG_IF_DISPDONE))
2433 				is_disp_copied(ofl, crp);
2434 		}
2435 	}
2436 
2437 	/*
2438 	 * GOT sections are created for dynamic executables and shared objects
2439 	 * if the FLG_OF_BLDGOT is set, or explicit reference has been made to
2440 	 * a GOT symbol.
2441 	 */
2442 	if (((ofl->ofl_flags & FLG_OF_RELOBJ) == 0) &&
2443 	    ((ofl->ofl_flags & FLG_OF_BLDGOT) ||
2444 	    ((((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_GOFTBL),
2445 	    SYM_NOHASH, NULL, ofl)) != NULL) ||
2446 	    ((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_GOFTBL_U),
2447 	    SYM_NOHASH, NULL, ofl)) != NULL)) &&
2448 	    (sdp->sd_ref != REF_DYN_SEEN)))) {
2449 		if (ld_make_got(ofl) == S_ERROR)
2450 			return (S_ERROR);
2451 
2452 		/* Allocate the GOT if required by target */
2453 		if ((ld_targ.t_mr.mr_allocate_got != NULL) &&
2454 		    ((*ld_targ.t_mr.mr_allocate_got)(ofl) == S_ERROR))
2455 			return (S_ERROR);
2456 	}
2457 
2458 	return (1);
2459 }
2460 
2461 /*
2462  * Simple comparison routine to be used by qsort() for
2463  * the sorting of the output relocation list.
2464  *
2465  * The reloc_compare() routine results in a relocation
2466  * table which is located on:
2467  *
2468  *	file referenced (NEEDED NDX)
2469  *	referenced symbol
2470  *	relocation offset
2471  *
2472  * This provides the most efficient traversal of the relocation
2473  * table at run-time.
2474  */
2475 static int
2476 reloc_compare(Reloc_list *i, Reloc_list *j)
2477 {
2478 
2479 	/*
2480 	 * first - sort on neededndx
2481 	 */
2482 	if (i->rl_key1 > j->rl_key1)
2483 		return (1);
2484 	if (i->rl_key1 < j->rl_key1)
2485 		return (-1);
2486 
2487 	/*
2488 	 * Then sort on symbol
2489 	 */
2490 	if ((uintptr_t)i->rl_key2 > (uintptr_t)j->rl_key2)
2491 		return (1);
2492 	if ((uintptr_t)i->rl_key2 < (uintptr_t)j->rl_key2)
2493 		return (-1);
2494 
2495 	/*
2496 	 * i->key2 == j->key2
2497 	 *
2498 	 * At this point we fall back to key2 (offsets) to
2499 	 * sort the output relocations.  Ideally this will
2500 	 * make for the most efficient processing of these
2501 	 * relocations at run-time.
2502 	 */
2503 	if (i->rl_key3 > j->rl_key3)
2504 		return (1);
2505 	if (i->rl_key3 < j->rl_key3)
2506 		return (-1);
2507 	return (0);
2508 }
2509 
2510 static uintptr_t
2511 do_sorted_outrelocs(Ofl_desc *ofl)
2512 {
2513 	Rel_desc	*orsp;
2514 	Rel_cachebuf	*rcbp;
2515 	Aliste		idx;
2516 	Reloc_list	*sorted_list;
2517 	Word		index = 0;
2518 	int		debug = 0;
2519 	uintptr_t	error = 1;
2520 
2521 	if ((sorted_list = libld_malloc((size_t)(sizeof (Reloc_list) *
2522 	    ofl->ofl_reloccnt))) == NULL)
2523 		return (S_ERROR);
2524 
2525 	/*
2526 	 * All but the PLT output relocations are sorted in the output file
2527 	 * based upon their sym_desc.  By doing this multiple relocations
2528 	 * against the same symbol are grouped together, thus when the object
2529 	 * is later relocated by ld.so.1 it will take advantage of the symbol
2530 	 * cache that ld.so.1 has.  This can significantly reduce the runtime
2531 	 * relocation cost of a dynamic object.
2532 	 *
2533 	 * PLT relocations are not sorted because the order of the PLT
2534 	 * relocations is used by ld.so.1 to determine what symbol a PLT
2535 	 * relocation is against.
2536 	 */
2537 	REL_CACHE_TRAVERSE(&ofl->ofl_outrels, idx, rcbp, orsp) {
2538 		if (debug == 0) {
2539 			DBG_CALL(Dbg_reloc_dooutrel(ofl->ofl_lml,
2540 			    ld_targ.t_m.m_rel_sht_type));
2541 			debug = 1;
2542 		}
2543 
2544 		/*
2545 		 * If it's a PLT relocation we output it now in the
2546 		 * order that it was originally processed.
2547 		 */
2548 		if (orsp->rel_flags & FLG_REL_PLT) {
2549 			if ((*ld_targ.t_mr.mr_perform_outreloc)(orsp, ofl) ==
2550 			    S_ERROR)
2551 				error = S_ERROR;
2552 			continue;
2553 		}
2554 
2555 		if ((orsp->rel_rtype == ld_targ.t_m.m_r_relative) ||
2556 		    (orsp->rel_rtype == ld_targ.t_m.m_r_register)) {
2557 			sorted_list[index].rl_key1 = 0;
2558 			sorted_list[index].rl_key2 =
2559 			    /* LINTED */
2560 			    (Sym_desc *)(uintptr_t)orsp->rel_rtype;
2561 		} else {
2562 			sorted_list[index].rl_key1 =
2563 			    orsp->rel_sym->sd_file->ifl_neededndx;
2564 			sorted_list[index].rl_key2 = orsp->rel_sym;
2565 		}
2566 
2567 		if (orsp->rel_flags & FLG_REL_GOT) {
2568 			sorted_list[index].rl_key3 =
2569 			    (*ld_targ.t_mr.mr_calc_got_offset)(orsp, ofl);
2570 		} else {
2571 			if (orsp->rel_rtype == ld_targ.t_m.m_r_register) {
2572 					sorted_list[index].rl_key3 = 0;
2573 			} else {
2574 				sorted_list[index].rl_key3 = orsp->rel_roffset +
2575 				    (Xword)_elf_getxoff(orsp->
2576 				    rel_isdesc->is_indata) +
2577 				    orsp->rel_isdesc->is_osdesc->
2578 				    os_shdr->sh_addr;
2579 			}
2580 		}
2581 
2582 		sorted_list[index++].rl_rsp = orsp;
2583 	}
2584 
2585 	qsort(sorted_list, (size_t)ofl->ofl_reloccnt, sizeof (Reloc_list),
2586 	    (int (*)(const void *, const void *))reloc_compare);
2587 
2588 	/*
2589 	 * All output relocations have now been sorted, go through
2590 	 * and process each relocation.
2591 	 */
2592 	for (index = 0; index < ofl->ofl_reloccnt; index++) {
2593 		if ((*ld_targ.t_mr.mr_perform_outreloc)
2594 		    (sorted_list[index].rl_rsp, ofl) == S_ERROR)
2595 			error = S_ERROR;
2596 	}
2597 
2598 	return (error);
2599 }
2600 
2601 /*
2602  * Process relocations.  Finds every input relocation section for each output
2603  * section and invokes reloc_section() to relocate that section.
2604  */
2605 uintptr_t
2606 ld_reloc_process(Ofl_desc *ofl)
2607 {
2608 	Sg_desc		*sgp;
2609 	Os_desc		*osp;
2610 	Word		ndx = 0;
2611 	ofl_flag_t	flags = ofl->ofl_flags;
2612 	Shdr		*shdr;
2613 
2614 	DBG_CALL(Dbg_basic_relocate(ofl->ofl_lml));
2615 
2616 	/*
2617 	 * Determine the index of the symbol table that will be referenced by
2618 	 * the relocation entries.
2619 	 */
2620 	if (OFL_ALLOW_DYNSYM(ofl))
2621 		/* LINTED */
2622 		ndx = (Word)elf_ndxscn(ofl->ofl_osdynsym->os_scn);
2623 	else if (!(flags & FLG_OF_STRIP) || (flags & FLG_OF_RELOBJ))
2624 		/* LINTED */
2625 		ndx = (Word)elf_ndxscn(ofl->ofl_ossymtab->os_scn);
2626 
2627 	/*
2628 	 * Re-initialize counters. These are used to provide relocation
2629 	 * offsets within the output buffers.
2630 	 */
2631 	ofl->ofl_relocpltsz = 0;
2632 	ofl->ofl_relocgotsz = 0;
2633 	ofl->ofl_relocbsssz = 0;
2634 
2635 	/*
2636 	 * Now that the output file is created and symbol update has occurred,
2637 	 * process the relocations collected in process_reloc().
2638 	 */
2639 	if (do_sorted_outrelocs(ofl) == S_ERROR)
2640 		return (S_ERROR);
2641 
2642 	if ((*ld_targ.t_mr.mr_do_activerelocs)(ofl) == S_ERROR)
2643 		return (S_ERROR);
2644 
2645 	if ((flags & FLG_OF_COMREL) == 0) {
2646 		Aliste	idx1;
2647 
2648 		/*
2649 		 * Process the relocation sections.  For each relocation
2650 		 * section generated for the output image update its shdr
2651 		 * information to reflect the symbol table it needs (sh_link)
2652 		 * and the section to which the relocation must be applied
2653 		 * (sh_info).
2654 		 */
2655 		for (APLIST_TRAVERSE(ofl->ofl_segs, idx1, sgp)) {
2656 			Os_desc *osp;
2657 			Aliste	idx2;
2658 
2659 			for (APLIST_TRAVERSE(sgp->sg_osdescs, idx2, osp)) {
2660 				if (osp->os_relosdesc == 0)
2661 					continue;
2662 
2663 				shdr = osp->os_relosdesc->os_shdr;
2664 				shdr->sh_link = ndx;
2665 				/* LINTED */
2666 				shdr->sh_info = (Word)elf_ndxscn(osp->os_scn);
2667 			}
2668 		}
2669 
2670 		/*
2671 		 * Since the .rel[a] section is not tied to any specific
2672 		 * section, we'd not have found it above.
2673 		 */
2674 		if ((osp = ofl->ofl_osrel) != NULL) {
2675 			shdr = osp->os_shdr;
2676 			shdr->sh_link = ndx;
2677 			shdr->sh_info = 0;
2678 		}
2679 	} else {
2680 		/*
2681 		 * We only have two relocation sections here, (PLT's,
2682 		 * coalesced) so just hit them directly instead of stepping
2683 		 * over the output sections.
2684 		 */
2685 		if ((osp = ofl->ofl_osrelhead) != NULL) {
2686 			shdr = osp->os_shdr;
2687 			shdr->sh_link = ndx;
2688 			shdr->sh_info = 0;
2689 		}
2690 		if (((osp = ofl->ofl_osplt) != NULL) && osp->os_relosdesc) {
2691 			shdr = osp->os_relosdesc->os_shdr;
2692 			shdr->sh_link = ndx;
2693 			/* LINTED */
2694 			shdr->sh_info = (Word)elf_ndxscn(osp->os_scn);
2695 		}
2696 	}
2697 
2698 	/*
2699 	 * If the -z text option was given, and we have output relocations
2700 	 * against a non-writable, allocatable section, issue a diagnostic and
2701 	 * return (the actual entries that caused this error would have been
2702 	 * output during the relocating section phase).
2703 	 */
2704 	if ((flags & (FLG_OF_PURETXT | FLG_OF_TEXTREL)) ==
2705 	    (FLG_OF_PURETXT | FLG_OF_TEXTREL)) {
2706 		eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_REL_REMAIN_3));
2707 		return (S_ERROR);
2708 	}
2709 
2710 	/*
2711 	 * Finally, initialize the first got entry with the address of the
2712 	 * .dynamic section (_DYNAMIC).
2713 	 */
2714 	if (flags & FLG_OF_DYNAMIC) {
2715 		if ((*ld_targ.t_mr.mr_fillin_gotplt)(ofl) == S_ERROR)
2716 			return (S_ERROR);
2717 	}
2718 
2719 	/*
2720 	 * Now that any GOT information has been written, display the debugging
2721 	 * information if required.
2722 	 */
2723 	if ((osp = ofl->ofl_osgot) != NULL)
2724 		DBG_CALL(Dbg_got_display(ofl, osp->os_shdr->sh_addr, 1,
2725 		    ld_targ.t_m.m_got_xnumber, ld_targ.t_m.m_got_entsize));
2726 
2727 	return (1);
2728 }
2729 
2730 /*
2731  * If the -z text option was given, and we have output relocations against a
2732  * non-writable, allocatable section, issue a diagnostic. Print offending
2733  * symbols in tabular form similar to the way undefined symbols are presented.
2734  * Called from reloc_count().  The actual fatal error condition is triggered on
2735  * in reloc_process() above.
2736  *
2737  * Note.  For historic reasons -ztext is not a default option (however all OS
2738  * shared object builds use this option).  It can be argued that this option
2739  * should also be default when generating an a.out (see 1163979).  However, if
2740  * an a.out contains text relocations it is either because the user is creating
2741  * something pretty weird (they've used the -b or -znodefs options), or because
2742  * the library against which they're building wasn't constructed correctly (ie.
2743  * a function has a NOTYPE type, in which case the a.out won't generate an
2744  * associated plt).  In the latter case the builder of the a.out can't do
2745  * anything to fix the error - thus we've chosen not to give the user an error,
2746  * or warning, for this case.
2747  */
2748 static void
2749 reloc_remain_title(Ofl_desc *ofl, int warning)
2750 {
2751 	const char	*str1;
2752 
2753 	if (warning)
2754 		str1 = MSG_INTL(MSG_REL_RMN_ITM_13);
2755 	else
2756 		str1 = MSG_INTL(MSG_REL_RMN_ITM_11);
2757 
2758 	eprintf(ofl->ofl_lml, ERR_NONE, MSG_INTL(MSG_REL_REMAIN_FMT_1), str1,
2759 	    MSG_INTL(MSG_REL_RMN_ITM_31), MSG_INTL(MSG_REL_RMN_ITM_12),
2760 	    MSG_INTL(MSG_REL_RMN_ITM_2), MSG_INTL(MSG_REL_RMN_ITM_32));
2761 }
2762 
2763 void
2764 ld_reloc_remain_entry(Rel_desc *orsp, Os_desc *osp, Ofl_desc *ofl)
2765 {
2766 	static Boolean	reloc_title = TRUE;
2767 
2768 	/*
2769 	 * -ztextoff
2770 	 */
2771 	if (ofl->ofl_flags1 & FLG_OF1_TEXTOFF)
2772 		return;
2773 
2774 	/*
2775 	 * Only give relocation errors against loadable read-only segments.
2776 	 */
2777 	if ((orsp->rel_rtype == ld_targ.t_m.m_r_register) || (!osp) ||
2778 	    (osp->os_sgdesc->sg_phdr.p_type != PT_LOAD) ||
2779 	    (osp->os_sgdesc->sg_phdr.p_flags & PF_W))
2780 		return;
2781 
2782 	/*
2783 	 * If we are in -ztextwarn mode, it's a silent error if a relocation is
2784 	 * due to a 'WEAK REFERENCE'.  This is because if the symbol is not
2785 	 * provided at run-time we will not perform a text-relocation.
2786 	 */
2787 	if (((ofl->ofl_flags & FLG_OF_PURETXT) == 0) &&
2788 	    (ELF_ST_BIND(orsp->rel_sym->sd_sym->st_info) == STB_WEAK) &&
2789 	    (orsp->rel_sym->sd_sym->st_shndx == SHN_UNDEF))
2790 		return;
2791 
2792 	if (reloc_title) {
2793 		/*
2794 		 * If building with '-ztext' then emit a fatal error.  If
2795 		 * building a executable then only emit a 'warning'.
2796 		 */
2797 		if (ofl->ofl_flags & FLG_OF_PURETXT)
2798 			reloc_remain_title(ofl, 0);
2799 		else
2800 			reloc_remain_title(ofl, 1);
2801 		reloc_title = FALSE;
2802 	}
2803 
2804 	eprintf(ofl->ofl_lml, ERR_NONE, MSG_INTL(MSG_REL_REMAIN_2),
2805 	    ld_reloc_sym_name(orsp), EC_OFF(orsp->rel_roffset),
2806 	    orsp->rel_isdesc->is_file->ifl_name);
2807 }
2808 
2809 /*
2810  * Generic encapsulation for generating a TLS got index.
2811  */
2812 uintptr_t
2813 ld_assign_got_TLS(Boolean local, Rel_desc *rsp, Ofl_desc *ofl, Sym_desc *sdp,
2814     Gotndx *gnp, Gotref gref, Word rflag, Word ortype, Word rtype1, Word rtype2)
2815 {
2816 	Word	rflags;
2817 
2818 	if ((*ld_targ.t_mr.mr_assign_got_ndx)(&(sdp->sd_GOTndxs), gnp,
2819 	    gref, ofl, rsp, sdp) == S_ERROR)
2820 		return (S_ERROR);
2821 
2822 	rflags = FLG_REL_GOT | rflag;
2823 	if (local)
2824 		rflags |= FLG_REL_SCNNDX;
2825 	rsp->rel_rtype = rtype1;
2826 
2827 	if ((*ld_targ.t_mr.mr_add_outrel)(rflags, rsp, ofl) == S_ERROR)
2828 		return (S_ERROR);
2829 
2830 	if (local && (gref == GOT_REF_TLSIE)) {
2831 		/*
2832 		 * If this is a local LE TLS symbol, then the symbol won't be
2833 		 * available at runtime.  The value of the local symbol will
2834 		 * be placed in the associated got entry, and the got
2835 		 * relocation is reassigned to a section symbol.
2836 		 */
2837 		if (ld_add_actrel(rflags, rsp, ofl) == S_ERROR)
2838 			return (S_ERROR);
2839 	}
2840 
2841 	if (rtype2) {
2842 		rflags = FLG_REL_GOT | rflag;
2843 		rsp->rel_rtype = rtype2;
2844 
2845 		if (local) {
2846 			if (ld_add_actrel(rflags, rsp, ofl) == S_ERROR)
2847 				return (S_ERROR);
2848 		} else {
2849 			if ((*ld_targ.t_mr.mr_add_outrel)(rflags, rsp, ofl) ==
2850 			    S_ERROR)
2851 				return (S_ERROR);
2852 		}
2853 	}
2854 
2855 	rsp->rel_rtype = ortype;
2856 
2857 	return (1);
2858 }
2859 
2860 /*
2861  * Move Section related function
2862  */
2863 static void
2864 newroffset_for_move(Sym_desc *sdp, Move *mvp, Xword offset1, Xword *offset2)
2865 {
2866 	Mv_desc		*mdp;
2867 	Aliste		idx;
2868 
2869 	/*
2870 	 * Search for matching move entry.
2871 	 */
2872 	for (ALIST_TRAVERSE(sdp->sd_move, idx, mdp)) {
2873 		if (mdp->md_move == mvp) {
2874 			/*
2875 			 * Update r_offset
2876 			 */
2877 			*offset2 = (Xword)((mdp->md_oidx - 1) * sizeof (Move) +
2878 			    offset1 % sizeof (Move));
2879 			return;
2880 		}
2881 	}
2882 }
2883 
2884 void
2885 ld_adj_movereloc(Ofl_desc *ofl, Rel_desc *arsp)
2886 {
2887 	Move		*move = arsp->rel_aux->ra_move->mr_move;
2888 	Sym_desc	*psdp = arsp->rel_aux->ra_move->mr_sym;
2889 	Xword		newoffset;
2890 
2891 	if (arsp->rel_flags & FLG_REL_MOVETAB) {
2892 		/*
2893 		 * We are relocating the move table itself.
2894 		 */
2895 		newroffset_for_move(psdp, move, arsp->rel_roffset,
2896 		    &newoffset);
2897 		DBG_CALL(Dbg_move_adjmovereloc(ofl->ofl_lml, arsp->rel_roffset,
2898 		    newoffset, psdp->sd_name));
2899 		arsp->rel_roffset = newoffset;
2900 	} else {
2901 		/*
2902 		 * We are expanding the partial symbol.  So we are generating
2903 		 * the relocation entry relocating the expanded partial symbol.
2904 		 */
2905 		arsp->rel_roffset += psdp->sd_sym->st_value -
2906 		    ofl->ofl_isparexpn->is_osdesc->os_shdr->sh_addr;
2907 		DBG_CALL(Dbg_move_adjexpandreloc(ofl->ofl_lml,
2908 		    arsp->rel_roffset, psdp->sd_name));
2909 	}
2910 }
2911 
2912 /*
2913  * Partially Initialized Symbol Handling routines
2914  * For RELA architecture, the second argument is reld->rel_raddend.  For REL
2915  * architecure, the second argument is the value stored at the relocation
2916  * target address.
2917  */
2918 Sym_desc *
2919 ld_am_I_partial(Rel_desc *reld, Xword val)
2920 {
2921 	Ifl_desc	*ifile = reld->rel_sym->sd_isc->is_file;
2922 	int 		nlocs = ifile->ifl_locscnt, i;
2923 
2924 	for (i = 1; i < nlocs; i++) {
2925 		Sym		*osym;
2926 		Sym_desc	*symd = ifile->ifl_oldndx[i];
2927 
2928 		if ((osym = symd->sd_osym) == 0)
2929 			continue;
2930 		if ((symd->sd_flags & FLG_SY_PAREXPN) == 0)
2931 			continue;
2932 		if ((osym->st_value <= val) &&
2933 		    (osym->st_value + osym->st_size > val))
2934 			return (symd);
2935 	}
2936 	return (NULL);
2937 }
2938 
2939 /*
2940  * Return True (1) if the code processing the given relocation
2941  * needs to perform byte swapping when accessing the section data.
2942  */
2943 int
2944 ld_swap_reloc_data(Ofl_desc *ofl, Rel_desc *rsp)
2945 {
2946 	/*
2947 	 * In a cross-link situation where the linker host and target
2948 	 * have opposite byte orders, it can be necessary to swap bytes
2949 	 * when doing relocation processing. This is indicated by the
2950 	 * presence of the FLG_OF1_ENCDIFF flag bit. However, swapping
2951 	 * is only needed for the section types that libelf doesn't
2952 	 * automatically xlate.
2953 	 */
2954 	if ((ofl->ofl_flags1 & FLG_OF1_ENCDIFF) != 0) {
2955 		switch (RELAUX_GET_OSDESC(rsp)->os_shdr->sh_type) {
2956 		case SHT_PROGBITS:
2957 			return (1);
2958 
2959 		case SHT_SPARC_GOTDATA:
2960 			if (ld_targ.t_m.m_mach ==
2961 			    LD_TARG_BYCLASS(EM_SPARC, EM_SPARCV9))
2962 				return (1);
2963 			break;
2964 
2965 		case SHT_AMD64_UNWIND:
2966 			if (ld_targ.t_m.m_mach == EM_AMD64)
2967 				return (1);
2968 			break;
2969 		}
2970 	}
2971 
2972 	/*
2973 	 * If FLG_OF1_ENCDIFF isn't set, or the section isn't
2974 	 * progbits (or similar), then no swapping is needed.
2975 	 */
2976 	return (0);
2977 }
2978 
2979 
2980 
2981 /*
2982  * Obtain the current value at the given relocation target.
2983  *
2984  * entry:
2985  *	ofl - Output file descriptor
2986  *	rsp - Relocation record
2987  *	data - Pointer to relocation target
2988  *	value - Address of variable to recieve value
2989  *
2990  * exit:
2991  *	The value of the data at the relocation target has
2992  *	been stored in value.
2993  */
2994 int
2995 ld_reloc_targval_get(Ofl_desc *ofl, Rel_desc *rsp, uchar_t *data, Xword *value)
2996 {
2997 	const Rel_entry	*rep;
2998 
2999 	rep = &ld_targ.t_mr.mr_reloc_table[rsp->rel_rtype];
3000 
3001 	switch (rep->re_fsize) {
3002 	case 1:
3003 		/* LINTED */
3004 		*value = (Xword) *((uchar_t *)data);
3005 		break;
3006 	case 2:
3007 		{
3008 			Half	v;
3009 			uchar_t	*v_bytes = (uchar_t *)&v;
3010 
3011 			if (OFL_SWAP_RELOC_DATA(ofl, rsp)) {
3012 				UL_ASSIGN_BSWAP_HALF(v_bytes, data);
3013 			} else {
3014 				UL_ASSIGN_HALF(v_bytes, data);
3015 			}
3016 			*value = (Xword) v;
3017 		}
3018 		break;
3019 	case 4:
3020 		{
3021 			Word	v;
3022 			uchar_t	*v_bytes = (uchar_t *)&v;
3023 
3024 			if (OFL_SWAP_RELOC_DATA(ofl, rsp)) {
3025 				UL_ASSIGN_BSWAP_WORD(v_bytes, data);
3026 			} else {
3027 				UL_ASSIGN_WORD(v_bytes, data);
3028 			}
3029 			*value = (Xword) v;
3030 		}
3031 		break;
3032 	default:
3033 		{
3034 			Conv_inv_buf_t inv_buf;
3035 			eprintf(ofl->ofl_lml, ERR_FATAL,
3036 			    MSG_INTL(MSG_REL_UNSUPSZ),
3037 			    conv_reloc_type(ld_targ.t_m.m_mach, rsp->rel_rtype,
3038 			    0, &inv_buf), rsp->rel_isdesc->is_file->ifl_name,
3039 			    ld_reloc_sym_name(rsp), (int)rep->re_fsize);
3040 		}
3041 		return (0);
3042 	}
3043 	return (1);
3044 }
3045 
3046 
3047 /*
3048  * Set the value at the given relocation target.
3049  *
3050  * entry:
3051  *	ofl - Output file descriptor
3052  *	rsp - Relocation record
3053  *	data - Pointer to relocation target
3054  *	value - Address of variable to recieve value
3055  *
3056  * exit:
3057  *	The value of the data at the relocation target has
3058  *	been stored in value.
3059  */
3060 int
3061 ld_reloc_targval_set(Ofl_desc *ofl, Rel_desc *rsp, uchar_t *data, Xword value)
3062 {
3063 	const Rel_entry	*rep;
3064 
3065 	rep = &ld_targ.t_mr.mr_reloc_table[rsp->rel_rtype];
3066 
3067 	switch (rep->re_fsize) {
3068 	case 1:
3069 		/* LINTED */
3070 		*((uchar_t *)data) = (uchar_t)value;
3071 		break;
3072 	case 2:
3073 		{
3074 			Half	v = (Half)value;
3075 			uchar_t	*v_bytes = (uchar_t *)&v;
3076 
3077 			if (OFL_SWAP_RELOC_DATA(ofl, rsp)) {
3078 				UL_ASSIGN_BSWAP_HALF(data, v_bytes);
3079 			} else {
3080 				UL_ASSIGN_HALF(data, v_bytes);
3081 			}
3082 		}
3083 		break;
3084 	case 4:
3085 		{
3086 			Word	v = (Word)value;
3087 			uchar_t	*v_bytes = (uchar_t *)&v;
3088 
3089 			if (OFL_SWAP_RELOC_DATA(ofl, rsp)) {
3090 				UL_ASSIGN_BSWAP_WORD(data, v_bytes);
3091 			} else {
3092 				UL_ASSIGN_WORD(data, v_bytes);
3093 			}
3094 		}
3095 		break;
3096 	default:
3097 		{
3098 			Conv_inv_buf_t inv_buf;
3099 			eprintf(ofl->ofl_lml, ERR_FATAL,
3100 			    MSG_INTL(MSG_REL_UNSUPSZ),
3101 			    conv_reloc_type(ld_targ.t_m.m_mach, rsp->rel_rtype,
3102 			    0, &inv_buf), rsp->rel_isdesc->is_file->ifl_name,
3103 			    ld_reloc_sym_name(rsp), (int)rep->re_fsize);
3104 		}
3105 		return (0);
3106 	}
3107 	return (1);
3108 }
3109 
3110 
3111 /*
3112  * Because of the combinations of 32-bit lib providing 64-bit support, and
3113  * visa-versa, the use of krtld's dorelocs can result in differing message
3114  * requirements that make msg.c/msg.h creation and chkmsg "interesting".
3115  * Thus the actual message files contain a couple of entries to satisfy
3116  * each architectures build.  Here we add dummy calls to quieten chkmsg.
3117  *
3118  * chkmsg: MSG_INTL(MSG_REL_NOFIT)
3119  * chkmsg: MSG_INTL(MSG_REL_NONALIGN)
3120  */
3121