xref: /titanic_41/usr/src/cmd/sgs/rtld/amd64/amd64_elf.c (revision 26fd77009b17f8c8fb32eb362584cfd635e87ad9)
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 2009 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"@(#)amd64_elf.c	1.25	08/07/30 SMI"
28 
29 /*
30  * amd64 machine dependent and ELF file class dependent functions.
31  * Contains routines for performing function binding and symbol relocations.
32  */
33 
34 #include	<stdio.h>
35 #include	<sys/elf.h>
36 #include	<sys/elf_amd64.h>
37 #include	<sys/mman.h>
38 #include	<dlfcn.h>
39 #include	<synch.h>
40 #include	<string.h>
41 #include	<debug.h>
42 #include	<reloc.h>
43 #include	<conv.h>
44 #include	"_rtld.h"
45 #include	"_audit.h"
46 #include	"_elf.h"
47 #include	"_inline.h"
48 #include	"msg.h"
49 
50 extern void	elf_rtbndr(Rt_map *, ulong_t, caddr_t);
51 
52 int
53 elf_mach_flags_check(Rej_desc *rej, Ehdr *ehdr)
54 {
55 	/*
56 	 * Check machine type and flags.
57 	 */
58 	if (ehdr->e_flags != 0) {
59 		rej->rej_type = SGS_REJ_BADFLAG;
60 		rej->rej_info = (uint_t)ehdr->e_flags;
61 		return (0);
62 	}
63 	return (1);
64 }
65 
66 void
67 ldso_plt_init(Rt_map *lmp)
68 {
69 	/*
70 	 * There is no need to analyze ld.so because we don't map in any of
71 	 * its dependencies.  However we may map these dependencies in later
72 	 * (as if ld.so had dlopened them), so initialize the plt and the
73 	 * permission information.
74 	 */
75 	if (PLTGOT(lmp))
76 		elf_plt_init((PLTGOT(lmp)), (caddr_t)lmp);
77 }
78 
79 static const uchar_t dyn_plt_template[] = {
80 /* 0x00 */  0x55,			/* pushq %rbp */
81 /* 0x01 */  0x48, 0x89, 0xe5,		/* movq  %rsp, %rbp */
82 /* 0x04 */  0x48, 0x83, 0xec, 0x10,	/* subq	 $0x10, %rsp */
83 /* 0x08 */  0x4c, 0x8d, 0x1d, 0x00,	/* leaq  trace_fields(%rip), %r11 */
84 		0x00, 0x00, 0x00,
85 /* 0x0f */  0x4c, 0x89, 0x5d, 0xf8,	/* movq  %r11, -0x8(%rbp) */
86 /* 0x13 */  0x49, 0xbb, 0x00, 0x00, 	/* movq  $elf_plt_trace, %r11 */
87 		0x00, 0x00, 0x00,
88 		0x00, 0x00, 0x00,
89 /* 0x1d */  0x41, 0xff, 0xe3		/* jmp   *%r11 */
90 /* 0x20 */
91 };
92 
93 /*
94  * And the virutal outstanding relocations against the
95  * above block are:
96  *
97  *	reloc		offset	Addend	symbol
98  *	R_AMD64_PC32	0x0b	-4	trace_fields
99  *	R_AMD64_64	0x15	0	elf_plt_trace
100  */
101 
102 #define	TRCREL1OFF	0x0b
103 #define	TRCREL2OFF	0x15
104 
105 int	dyn_plt_ent_size = sizeof (dyn_plt_template);
106 
107 /*
108  * the dynamic plt entry is:
109  *
110  *	pushq	%rbp
111  *	movq	%rsp, %rbp
112  *	subq	$0x10, %rsp
113  *	leaq	trace_fields(%rip), %r11
114  *	movq	%r11, -0x8(%rbp)
115  *	movq	$elf_plt_trace, %r11
116  *	jmp	*%r11
117  * dyn_data:
118  *	.align  8
119  *	uintptr_t	reflmp
120  *	uintptr_t	deflmp
121  *	uint_t		symndx
122  *	uint_t		sb_flags
123  *	Sym		symdef
124  */
125 static caddr_t
126 elf_plt_trace_write(ulong_t roffset, Rt_map *rlmp, Rt_map *dlmp, Sym *sym,
127     uint_t symndx, uint_t pltndx, caddr_t to, uint_t sb_flags, int *fail)
128 {
129 	extern int	elf_plt_trace();
130 	ulong_t		got_entry;
131 	uchar_t		*dyn_plt;
132 	uintptr_t	*dyndata;
133 
134 	/*
135 	 * We only need to add the glue code if there is an auditing
136 	 * library that is interested in this binding.
137 	 */
138 	dyn_plt = (uchar_t *)((uintptr_t)AUDINFO(rlmp)->ai_dynplts +
139 	    (pltndx * dyn_plt_ent_size));
140 
141 	/*
142 	 * Have we initialized this dynamic plt entry yet?  If we haven't do it
143 	 * now.  Otherwise this function has been called before, but from a
144 	 * different plt (ie. from another shared object).  In that case
145 	 * we just set the plt to point to the new dyn_plt.
146 	 */
147 	if (*dyn_plt == 0) {
148 		Sym	*symp;
149 		Xword	symvalue;
150 		Lm_list	*lml = LIST(rlmp);
151 
152 		(void) memcpy((void *)dyn_plt, dyn_plt_template,
153 		    sizeof (dyn_plt_template));
154 		dyndata = (uintptr_t *)((uintptr_t)dyn_plt +
155 		    ROUND(sizeof (dyn_plt_template), M_WORD_ALIGN));
156 
157 		/*
158 		 * relocate:
159 		 *	leaq	trace_fields(%rip), %r11
160 		 *	R_AMD64_PC32	0x0b	-4	trace_fields
161 		 */
162 		symvalue = (Xword)((uintptr_t)dyndata -
163 		    (uintptr_t)(&dyn_plt[TRCREL1OFF]) - 4);
164 		if (do_reloc_rtld(R_AMD64_PC32, &dyn_plt[TRCREL1OFF],
165 		    &symvalue, MSG_ORIG(MSG_SYM_LADYNDATA),
166 		    MSG_ORIG(MSG_SPECFIL_DYNPLT), lml) == 0) {
167 			*fail = 1;
168 			return (0);
169 		}
170 
171 		/*
172 		 * relocating:
173 		 *	movq	$elf_plt_trace, %r11
174 		 *	R_AMD64_64	0x15	0	elf_plt_trace
175 		 */
176 		symvalue = (Xword)elf_plt_trace;
177 		if (do_reloc_rtld(R_AMD64_64, &dyn_plt[TRCREL2OFF],
178 		    &symvalue, MSG_ORIG(MSG_SYM_ELFPLTTRACE),
179 		    MSG_ORIG(MSG_SPECFIL_DYNPLT), lml) == 0) {
180 			*fail = 1;
181 			return (0);
182 		}
183 
184 		*dyndata++ = (uintptr_t)rlmp;
185 		*dyndata++ = (uintptr_t)dlmp;
186 		*dyndata = (uintptr_t)(((uint64_t)sb_flags << 32) | symndx);
187 		dyndata++;
188 		symp = (Sym *)dyndata;
189 		*symp = *sym;
190 		symp->st_value = (Addr)to;
191 	}
192 
193 	got_entry = (ulong_t)roffset;
194 	*(ulong_t *)got_entry = (ulong_t)dyn_plt;
195 	return ((caddr_t)dyn_plt);
196 }
197 
198 /*
199  * Function binding routine - invoked on the first call to a function through
200  * the procedure linkage table;
201  * passes first through an assembly language interface.
202  *
203  * Takes the offset into the relocation table of the associated
204  * relocation entry and the address of the link map (rt_private_map struct)
205  * for the entry.
206  *
207  * Returns the address of the function referenced after re-writing the PLT
208  * entry to invoke the function directly.
209  *
210  * On error, causes process to terminate with a signal.
211  */
212 ulong_t
213 elf_bndr(Rt_map *lmp, ulong_t pltndx, caddr_t from)
214 {
215 	Rt_map		*nlmp, *llmp;
216 	ulong_t		addr, reloff, symval, rsymndx;
217 	char		*name;
218 	Rela		*rptr;
219 	Sym		*rsym, *nsym;
220 	uint_t		binfo, sb_flags = 0, dbg_class;
221 	Slookup		sl;
222 	int		entry, lmflags;
223 	Lm_list		*lml;
224 
225 	/*
226 	 * For compatibility with libthread (TI_VERSION 1) we track the entry
227 	 * value.  A zero value indicates we have recursed into ld.so.1 to
228 	 * further process a locking request.  Under this recursion we disable
229 	 * tsort and cleanup activities.
230 	 */
231 	entry = enter(0);
232 
233 	lml = LIST(lmp);
234 	if ((lmflags = lml->lm_flags) & LML_FLG_RTLDLM) {
235 		dbg_class = dbg_desc->d_class;
236 		dbg_desc->d_class = 0;
237 	}
238 
239 	/*
240 	 * Perform some basic sanity checks.  If we didn't get a load map or
241 	 * the relocation offset is invalid then its possible someone has walked
242 	 * over the .got entries or jumped to plt0 out of the blue.
243 	 */
244 	if ((!lmp) && (pltndx <=
245 	    (ulong_t)PLTRELSZ(lmp) / (ulong_t)RELENT(lmp))) {
246 		Conv_inv_buf_t inv_buf;
247 
248 		eprintf(lml, ERR_FATAL, MSG_INTL(MSG_REL_PLTREF),
249 		    conv_reloc_amd64_type(R_AMD64_JUMP_SLOT, 0, &inv_buf),
250 		    EC_NATPTR(lmp), EC_XWORD(pltndx), EC_NATPTR(from));
251 		rtldexit(lml, 1);
252 	}
253 	reloff = pltndx * (ulong_t)RELENT(lmp);
254 
255 	/*
256 	 * Use relocation entry to get symbol table entry and symbol name.
257 	 */
258 	addr = (ulong_t)JMPREL(lmp);
259 	rptr = (Rela *)(addr + reloff);
260 	rsymndx = ELF_R_SYM(rptr->r_info);
261 	rsym = (Sym *)((ulong_t)SYMTAB(lmp) + (rsymndx * SYMENT(lmp)));
262 	name = (char *)(STRTAB(lmp) + rsym->st_name);
263 
264 	/*
265 	 * Determine the last link-map of this list, this'll be the starting
266 	 * point for any tsort() processing.
267 	 */
268 	llmp = lml->lm_tail;
269 
270 	/*
271 	 * Find definition for symbol.  Initialize the symbol lookup data
272 	 * structure.
273 	 */
274 	SLOOKUP_INIT(sl, name, lmp, lml->lm_head, ld_entry_cnt, 0,
275 	    rsymndx, rsym, 0, LKUP_DEFT);
276 
277 	if ((nsym = lookup_sym(&sl, &nlmp, &binfo, NULL)) == 0) {
278 		eprintf(lml, ERR_FATAL, MSG_INTL(MSG_REL_NOSYM), NAME(lmp),
279 		    demangle(name));
280 		rtldexit(lml, 1);
281 	}
282 
283 	symval = nsym->st_value;
284 	if (!(FLAGS(nlmp) & FLG_RT_FIXED) &&
285 	    (nsym->st_shndx != SHN_ABS))
286 		symval += ADDR(nlmp);
287 	if ((lmp != nlmp) && ((FLAGS1(nlmp) & FL1_RT_NOINIFIN) == 0)) {
288 		/*
289 		 * Record that this new link map is now bound to the caller.
290 		 */
291 		if (bind_one(lmp, nlmp, BND_REFER) == 0)
292 			rtldexit(lml, 1);
293 	}
294 
295 	if ((lml->lm_tflags | AFLAGS(lmp)) & LML_TFLG_AUD_SYMBIND) {
296 		uint_t	symndx = (((uintptr_t)nsym -
297 		    (uintptr_t)SYMTAB(nlmp)) / SYMENT(nlmp));
298 		symval = audit_symbind(lmp, nlmp, nsym, symndx, symval,
299 		    &sb_flags);
300 	}
301 
302 	if (!(rtld_flags & RT_FL_NOBIND)) {
303 		addr = rptr->r_offset;
304 		if (!(FLAGS(lmp) & FLG_RT_FIXED))
305 			addr += ADDR(lmp);
306 		if (((lml->lm_tflags | AFLAGS(lmp)) &
307 		    (LML_TFLG_AUD_PLTENTER | LML_TFLG_AUD_PLTEXIT)) &&
308 		    AUDINFO(lmp)->ai_dynplts) {
309 			int	fail = 0;
310 			uint_t	pltndx = reloff / sizeof (Rela);
311 			uint_t	symndx = (((uintptr_t)nsym -
312 			    (uintptr_t)SYMTAB(nlmp)) / SYMENT(nlmp));
313 
314 			symval = (ulong_t)elf_plt_trace_write(addr, lmp, nlmp,
315 			    nsym, symndx, pltndx, (caddr_t)symval, sb_flags,
316 			    &fail);
317 			if (fail)
318 				rtldexit(lml, 1);
319 		} else {
320 			/*
321 			 * Write standard PLT entry to jump directly
322 			 * to newly bound function.
323 			 */
324 			*(ulong_t *)addr = symval;
325 		}
326 	}
327 
328 	/*
329 	 * Print binding information and rebuild PLT entry.
330 	 */
331 	DBG_CALL(Dbg_bind_global(lmp, (Addr)from, (Off)(from - ADDR(lmp)),
332 	    (Xword)(reloff / sizeof (Rela)), PLT_T_FULL, nlmp, (Addr)symval,
333 	    nsym->st_value, name, binfo));
334 
335 	/*
336 	 * Complete any processing for newly loaded objects.  Note we don't
337 	 * know exactly where any new objects are loaded (we know the object
338 	 * that supplied the symbol, but others may have been loaded lazily as
339 	 * we searched for the symbol), so sorting starts from the last
340 	 * link-map know on entry to this routine.
341 	 */
342 	if (entry)
343 		load_completion(llmp);
344 
345 	/*
346 	 * Some operations like dldump() or dlopen()'ing a relocatable object
347 	 * result in objects being loaded on rtld's link-map, make sure these
348 	 * objects are initialized also.
349 	 */
350 	if ((LIST(nlmp)->lm_flags & LML_FLG_RTLDLM) && LIST(nlmp)->lm_init)
351 		load_completion(nlmp);
352 
353 	/*
354 	 * Make sure the object to which we've bound has had it's .init fired.
355 	 * Cleanup before return to user code.
356 	 */
357 	if (entry) {
358 		is_dep_init(nlmp, lmp);
359 		leave(lml, 0);
360 	}
361 
362 	if (lmflags & LML_FLG_RTLDLM)
363 		dbg_desc->d_class = dbg_class;
364 
365 	return (symval);
366 }
367 
368 /*
369  * Read and process the relocations for one link object, we assume all
370  * relocation sections for loadable segments are stored contiguously in
371  * the file.
372  */
373 int
374 elf_reloc(Rt_map *lmp, uint_t plt, int *in_nfavl, APlist **textrel)
375 {
376 	ulong_t		relbgn, relend, relsiz, basebgn;
377 	ulong_t		pltbgn, pltend, _pltbgn, _pltend;
378 	ulong_t		roffset, rsymndx, psymndx = 0;
379 	ulong_t		dsymndx;
380 	uchar_t		rtype;
381 	long		reladd, value, pvalue;
382 	Sym		*symref, *psymref, *symdef, *psymdef;
383 	char		*name, *pname;
384 	Rt_map		*_lmp, *plmp;
385 	int		ret = 1, noplt = 0;
386 	int		relacount = RELACOUNT(lmp), plthint = 0;
387 	Rela		*rel;
388 	uint_t		binfo, pbinfo;
389 	APlist		*bound = NULL;
390 
391 	/*
392 	 * Although only necessary for lazy binding, initialize the first
393 	 * global offset entry to go to elf_rtbndr().  dbx(1) seems
394 	 * to find this useful.
395 	 */
396 	if ((plt == 0) && PLTGOT(lmp)) {
397 		mmapobj_result_t	*mpp;
398 
399 		/*
400 		 * Make sure the segment is writable.
401 		 */
402 		if ((((mpp =
403 		    find_segment((caddr_t)PLTGOT(lmp), lmp)) != NULL) &&
404 		    ((mpp->mr_prot & PROT_WRITE) == 0)) &&
405 		    ((set_prot(lmp, mpp, 1) == 0) ||
406 		    (aplist_append(textrel, mpp, AL_CNT_TEXTREL) == NULL)))
407 			return (0);
408 
409 		elf_plt_init(PLTGOT(lmp), (caddr_t)lmp);
410 	}
411 
412 	/*
413 	 * Initialize the plt start and end addresses.
414 	 */
415 	if ((pltbgn = (ulong_t)JMPREL(lmp)) != 0)
416 		pltend = pltbgn + (ulong_t)(PLTRELSZ(lmp));
417 
418 
419 	relsiz = (ulong_t)(RELENT(lmp));
420 	basebgn = ADDR(lmp);
421 
422 	if (PLTRELSZ(lmp))
423 		plthint = PLTRELSZ(lmp) / relsiz;
424 
425 	/*
426 	 * If we've been called upon to promote an RTLD_LAZY object to an
427 	 * RTLD_NOW then we're only interested in scaning the .plt table.
428 	 * An uninitialized .plt is the case where the associated got entry
429 	 * points back to the plt itself.  Determine the range of the real .plt
430 	 * entries using the _PROCEDURE_LINKAGE_TABLE_ symbol.
431 	 */
432 	if (plt) {
433 		Slookup	sl;
434 
435 		relbgn = pltbgn;
436 		relend = pltend;
437 		if (!relbgn || (relbgn == relend))
438 			return (1);
439 
440 		/*
441 		 * Initialize the symbol lookup data structure.
442 		 */
443 		SLOOKUP_INIT(sl, MSG_ORIG(MSG_SYM_PLT), lmp, lmp, ld_entry_cnt,
444 		    elf_hash(MSG_ORIG(MSG_SYM_PLT)), 0, 0, 0, LKUP_DEFT);
445 
446 		if ((symdef = elf_find_sym(&sl, &_lmp, &binfo, NULL)) == 0)
447 			return (1);
448 
449 		_pltbgn = symdef->st_value;
450 		if (!(FLAGS(lmp) & FLG_RT_FIXED) &&
451 		    (symdef->st_shndx != SHN_ABS))
452 			_pltbgn += basebgn;
453 		_pltend = _pltbgn + (((PLTRELSZ(lmp) / relsiz)) *
454 		    M_PLT_ENTSIZE) + M_PLT_RESERVSZ;
455 
456 	} else {
457 		/*
458 		 * The relocation sections appear to the run-time linker as a
459 		 * single table.  Determine the address of the beginning and end
460 		 * of this table.  There are two different interpretations of
461 		 * the ABI at this point:
462 		 *
463 		 *   o	The REL table and its associated RELSZ indicate the
464 		 *	concatenation of *all* relocation sections (this is the
465 		 *	model our link-editor constructs).
466 		 *
467 		 *   o	The REL table and its associated RELSZ indicate the
468 		 *	concatenation of all *but* the .plt relocations.  These
469 		 *	relocations are specified individually by the JMPREL and
470 		 *	PLTRELSZ entries.
471 		 *
472 		 * Determine from our knowledege of the relocation range and
473 		 * .plt range, the range of the total relocation table.  Note
474 		 * that one other ABI assumption seems to be that the .plt
475 		 * relocations always follow any other relocations, the
476 		 * following range checking drops that assumption.
477 		 */
478 		relbgn = (ulong_t)(REL(lmp));
479 		relend = relbgn + (ulong_t)(RELSZ(lmp));
480 		if (pltbgn) {
481 			if (!relbgn || (relbgn > pltbgn))
482 				relbgn = pltbgn;
483 			if (!relbgn || (relend < pltend))
484 				relend = pltend;
485 		}
486 	}
487 	if (!relbgn || (relbgn == relend)) {
488 		DBG_CALL(Dbg_reloc_run(lmp, 0, plt, DBG_REL_NONE));
489 		return (1);
490 	}
491 	DBG_CALL(Dbg_reloc_run(lmp, M_REL_SHT_TYPE, plt, DBG_REL_START));
492 
493 	/*
494 	 * If we're processing a dynamic executable in lazy mode there is no
495 	 * need to scan the .rel.plt table, however if we're processing a shared
496 	 * object in lazy mode the .got addresses associated to each .plt must
497 	 * be relocated to reflect the location of the shared object.
498 	 */
499 	if (pltbgn && ((MODE(lmp) & RTLD_NOW) == 0) &&
500 	    (FLAGS(lmp) & FLG_RT_FIXED))
501 		noplt = 1;
502 
503 	/*
504 	 * Loop through relocations.
505 	 */
506 	while (relbgn < relend) {
507 		mmapobj_result_t	*mpp;
508 		uint_t			sb_flags = 0;
509 
510 		rtype = ELF_R_TYPE(((Rela *)relbgn)->r_info, M_MACH);
511 
512 		/*
513 		 * If this is a RELATIVE relocation in a shared object (the
514 		 * common case), and if we are not debugging, then jump into a
515 		 * tighter relocation loop (elf_reloc_relative).
516 		 */
517 		if ((rtype == R_AMD64_RELATIVE) &&
518 		    ((FLAGS(lmp) & FLG_RT_FIXED) == 0) && (DBG_ENABLED == 0)) {
519 			if (relacount) {
520 				relbgn = elf_reloc_relative_count(relbgn,
521 				    relacount, relsiz, basebgn, lmp, textrel);
522 				relacount = 0;
523 			} else {
524 				relbgn = elf_reloc_relative(relbgn, relend,
525 				    relsiz, basebgn, lmp, textrel);
526 			}
527 			if (relbgn >= relend)
528 				break;
529 			rtype = ELF_R_TYPE(((Rela *)relbgn)->r_info, M_MACH);
530 		}
531 
532 		roffset = ((Rela *)relbgn)->r_offset;
533 
534 		/*
535 		 * If this is a shared object, add the base address to offset.
536 		 */
537 		if (!(FLAGS(lmp) & FLG_RT_FIXED)) {
538 			/*
539 			 * If we're processing lazy bindings, we have to step
540 			 * through the plt entries and add the base address
541 			 * to the corresponding got entry.
542 			 */
543 			if (plthint && (plt == 0) &&
544 			    (rtype == R_AMD64_JUMP_SLOT) &&
545 			    ((MODE(lmp) & RTLD_NOW) == 0)) {
546 				/*
547 				 * The PLT relocations (for lazy bindings)
548 				 * are additive to what's already in the GOT.
549 				 * This differs to what happens in
550 				 * elf_reloc_relacount() and that's why we
551 				 * just do it inline here.
552 				 */
553 				for (roffset = ((Rela *)relbgn)->r_offset;
554 				    plthint; plthint--) {
555 					roffset += basebgn;
556 
557 					/*
558 					 * Perform the actual relocation.
559 					 */
560 					*((ulong_t *)roffset) += basebgn;
561 
562 					relbgn += relsiz;
563 					roffset = ((Rela *)relbgn)->r_offset;
564 
565 				}
566 				continue;
567 			}
568 			roffset += basebgn;
569 		}
570 
571 		reladd = (long)(((Rela *)relbgn)->r_addend);
572 		rsymndx = ELF_R_SYM(((Rela *)relbgn)->r_info);
573 		rel = (Rela *)relbgn;
574 		relbgn += relsiz;
575 
576 		/*
577 		 * Optimizations.
578 		 */
579 		if (rtype == R_AMD64_NONE)
580 			continue;
581 		if (noplt && ((ulong_t)rel >= pltbgn) &&
582 		    ((ulong_t)rel < pltend)) {
583 			relbgn = pltend;
584 			continue;
585 		}
586 
587 		/*
588 		 * If we're promoting plts, determine if this one has already
589 		 * been written.
590 		 */
591 		if (plt && ((*(ulong_t *)roffset < _pltbgn) ||
592 		    (*(ulong_t *)roffset > _pltend)))
593 			continue;
594 
595 		/*
596 		 * If this relocation is not against part of the image
597 		 * mapped into memory we skip it.
598 		 */
599 		if ((mpp = find_segment((caddr_t)roffset, lmp)) == NULL) {
600 			elf_reloc_bad(lmp, (void *)rel, rtype, roffset,
601 			    rsymndx);
602 			continue;
603 		}
604 
605 		binfo = 0;
606 		/*
607 		 * If a symbol index is specified then get the symbol table
608 		 * entry, locate the symbol definition, and determine its
609 		 * address.
610 		 */
611 		if (rsymndx) {
612 			/*
613 			 * Get the local symbol table entry.
614 			 */
615 			symref = (Sym *)((ulong_t)SYMTAB(lmp) +
616 			    (rsymndx * SYMENT(lmp)));
617 
618 			/*
619 			 * If this is a local symbol, just use the base address.
620 			 * (we should have no local relocations in the
621 			 * executable).
622 			 */
623 			if (ELF_ST_BIND(symref->st_info) == STB_LOCAL) {
624 				value = basebgn;
625 				name = (char *)0;
626 
627 				/*
628 				 * Special case TLS relocations.
629 				 */
630 				if (rtype == R_AMD64_DTPMOD64) {
631 					/*
632 					 * Use the TLS modid.
633 					 */
634 					value = TLSMODID(lmp);
635 
636 				} else if ((rtype == R_AMD64_TPOFF64) ||
637 				    (rtype == R_AMD64_TPOFF32)) {
638 					if ((value = elf_static_tls(lmp, symref,
639 					    rel, rtype, 0, roffset, 0)) == 0) {
640 						ret = 0;
641 						break;
642 					}
643 				}
644 			} else {
645 				/*
646 				 * If the symbol index is equal to the previous
647 				 * symbol index relocation we processed then
648 				 * reuse the previous values. (Note that there
649 				 * have been cases where a relocation exists
650 				 * against a copy relocation symbol, our ld(1)
651 				 * should optimize this away, but make sure we
652 				 * don't use the same symbol information should
653 				 * this case exist).
654 				 */
655 				if ((rsymndx == psymndx) &&
656 				    (rtype != R_AMD64_COPY)) {
657 					/* LINTED */
658 					if (psymdef == 0) {
659 						DBG_CALL(Dbg_bind_weak(lmp,
660 						    (Addr)roffset, (Addr)
661 						    (roffset - basebgn), name));
662 						continue;
663 					}
664 					/* LINTED */
665 					value = pvalue;
666 					/* LINTED */
667 					name = pname;
668 					/* LINTED */
669 					symdef = psymdef;
670 					/* LINTED */
671 					symref = psymref;
672 					/* LINTED */
673 					_lmp = plmp;
674 					/* LINTED */
675 					binfo = pbinfo;
676 
677 					if ((LIST(_lmp)->lm_tflags |
678 					    AFLAGS(_lmp)) &
679 					    LML_TFLG_AUD_SYMBIND) {
680 						value = audit_symbind(lmp, _lmp,
681 						    /* LINTED */
682 						    symdef, dsymndx, value,
683 						    &sb_flags);
684 					}
685 				} else {
686 					Slookup		sl;
687 
688 					/*
689 					 * Lookup the symbol definition.
690 					 * Initialize the symbol lookup data
691 					 * structure.
692 					 */
693 					name = (char *)(STRTAB(lmp) +
694 					    symref->st_name);
695 
696 					SLOOKUP_INIT(sl, name, lmp, 0,
697 					    ld_entry_cnt, 0, rsymndx, symref,
698 					    rtype, LKUP_STDRELOC);
699 
700 					symdef = lookup_sym(&sl, &_lmp,
701 					    &binfo, in_nfavl);
702 
703 					/*
704 					 * If the symbol is not found and the
705 					 * reference was not to a weak symbol,
706 					 * report an error.  Weak references
707 					 * may be unresolved.
708 					 */
709 					/* BEGIN CSTYLED */
710 					if (symdef == 0) {
711 					    if (sl.sl_bind != STB_WEAK) {
712 						if (elf_reloc_error(lmp, name,
713 						    rel, binfo))
714 							continue;
715 
716 						ret = 0;
717 						break;
718 
719 					    } else {
720 						psymndx = rsymndx;
721 						psymdef = 0;
722 
723 						DBG_CALL(Dbg_bind_weak(lmp,
724 						    (Addr)roffset, (Addr)
725 						    (roffset - basebgn), name));
726 						continue;
727 					    }
728 					}
729 					/* END CSTYLED */
730 
731 					/*
732 					 * If symbol was found in an object
733 					 * other than the referencing object
734 					 * then record the binding.
735 					 */
736 					if ((lmp != _lmp) && ((FLAGS1(_lmp) &
737 					    FL1_RT_NOINIFIN) == 0)) {
738 						if (aplist_test(&bound, _lmp,
739 						    AL_CNT_RELBIND) == 0) {
740 							ret = 0;
741 							break;
742 						}
743 					}
744 
745 					/*
746 					 * Calculate the location of definition;
747 					 * symbol value plus base address of
748 					 * containing shared object.
749 					 */
750 					if (IS_SIZE(rtype))
751 						value = symdef->st_size;
752 					else
753 						value = symdef->st_value;
754 
755 					if (!(FLAGS(_lmp) & FLG_RT_FIXED) &&
756 					    !(IS_SIZE(rtype)) &&
757 					    (symdef->st_shndx != SHN_ABS) &&
758 					    (ELF_ST_TYPE(symdef->st_info) !=
759 					    STT_TLS))
760 						value += ADDR(_lmp);
761 
762 					/*
763 					 * Retain this symbol index and the
764 					 * value in case it can be used for the
765 					 * subsequent relocations.
766 					 */
767 					if (rtype != R_AMD64_COPY) {
768 						psymndx = rsymndx;
769 						pvalue = value;
770 						pname = name;
771 						psymdef = symdef;
772 						psymref = symref;
773 						plmp = _lmp;
774 						pbinfo = binfo;
775 					}
776 					if ((LIST(_lmp)->lm_tflags |
777 					    AFLAGS(_lmp)) &
778 					    LML_TFLG_AUD_SYMBIND) {
779 						dsymndx = (((uintptr_t)symdef -
780 						    (uintptr_t)SYMTAB(_lmp)) /
781 						    SYMENT(_lmp));
782 						value = audit_symbind(lmp, _lmp,
783 						    symdef, dsymndx, value,
784 						    &sb_flags);
785 					}
786 				}
787 
788 				/*
789 				 * If relocation is PC-relative, subtract
790 				 * offset address.
791 				 */
792 				if (IS_PC_RELATIVE(rtype))
793 					value -= roffset;
794 
795 				/*
796 				 * Special case TLS relocations.
797 				 */
798 				if (rtype == R_AMD64_DTPMOD64) {
799 					/*
800 					 * Relocation value is the TLS modid.
801 					 */
802 					value = TLSMODID(_lmp);
803 
804 				} else if ((rtype == R_AMD64_TPOFF64) ||
805 				    (rtype == R_AMD64_TPOFF32)) {
806 					if ((value = elf_static_tls(_lmp,
807 					    symdef, rel, rtype, name, roffset,
808 					    value)) == 0) {
809 						ret = 0;
810 						break;
811 					}
812 				}
813 			}
814 		} else {
815 			/*
816 			 * Special cases.
817 			 */
818 			if (rtype == R_AMD64_DTPMOD64) {
819 				/*
820 				 * TLS relocation value is the TLS modid.
821 				 */
822 				value = TLSMODID(lmp);
823 			} else
824 				value = basebgn;
825 			name = (char *)0;
826 		}
827 
828 		DBG_CALL(Dbg_reloc_in(LIST(lmp), ELF_DBG_RTLD, M_MACH,
829 		    M_REL_SHT_TYPE, rel, NULL, 0, name));
830 
831 		/*
832 		 * Make sure the segment is writable.
833 		 */
834 		if (((mpp->mr_prot & PROT_WRITE) == 0) &&
835 		    ((set_prot(lmp, mpp, 1) == 0) ||
836 		    (aplist_append(textrel, mpp, AL_CNT_TEXTREL) == NULL))) {
837 			ret = 0;
838 			break;
839 		}
840 
841 		/*
842 		 * Call relocation routine to perform required relocation.
843 		 */
844 		switch (rtype) {
845 		case R_AMD64_COPY:
846 			if (elf_copy_reloc(name, symref, lmp, (void *)roffset,
847 			    symdef, _lmp, (const void *)value) == 0)
848 				ret = 0;
849 			break;
850 		case R_AMD64_JUMP_SLOT:
851 			if (((LIST(lmp)->lm_tflags | AFLAGS(lmp)) &
852 			    (LML_TFLG_AUD_PLTENTER | LML_TFLG_AUD_PLTEXIT)) &&
853 			    AUDINFO(lmp)->ai_dynplts) {
854 				int	fail = 0;
855 				int	pltndx = (((ulong_t)rel -
856 				    (uintptr_t)JMPREL(lmp)) / relsiz);
857 				int	symndx = (((uintptr_t)symdef -
858 				    (uintptr_t)SYMTAB(_lmp)) / SYMENT(_lmp));
859 
860 				(void) elf_plt_trace_write(roffset, lmp, _lmp,
861 				    symdef, symndx, pltndx, (caddr_t)value,
862 				    sb_flags, &fail);
863 				if (fail)
864 					ret = 0;
865 			} else {
866 				/*
867 				 * Write standard PLT entry to jump directly
868 				 * to newly bound function.
869 				 */
870 				DBG_CALL(Dbg_reloc_apply_val(LIST(lmp),
871 				    ELF_DBG_RTLD, (Xword)roffset,
872 				    (Xword)value));
873 				*(ulong_t *)roffset = value;
874 			}
875 			break;
876 		default:
877 			value += reladd;
878 			/*
879 			 * Write the relocation out.
880 			 */
881 			if (do_reloc_rtld(rtype, (uchar_t *)roffset,
882 			    (Xword *)&value, name, NAME(lmp), LIST(lmp)) == 0)
883 				ret = 0;
884 
885 			DBG_CALL(Dbg_reloc_apply_val(LIST(lmp), ELF_DBG_RTLD,
886 			    (Xword)roffset, (Xword)value));
887 		}
888 
889 		if ((ret == 0) &&
890 		    ((LIST(lmp)->lm_flags & LML_FLG_TRC_WARN) == 0))
891 			break;
892 
893 		if (binfo) {
894 			DBG_CALL(Dbg_bind_global(lmp, (Addr)roffset,
895 			    (Off)(roffset - basebgn), (Xword)(-1), PLT_T_FULL,
896 			    _lmp, (Addr)value, symdef->st_value, name, binfo));
897 		}
898 	}
899 
900 	return (relocate_finish(lmp, bound, ret));
901 }
902 
903 /*
904  * Initialize the first few got entries so that function calls go to
905  * elf_rtbndr:
906  *
907  *	GOT[GOT_XLINKMAP] =	the address of the link map
908  *	GOT[GOT_XRTLD] =	the address of rtbinder
909  */
910 void
911 elf_plt_init(void *got, caddr_t l)
912 {
913 	uint64_t	*_got;
914 	/* LINTED */
915 	Rt_map		*lmp = (Rt_map *)l;
916 
917 	_got = (uint64_t *)got + M_GOT_XLINKMAP;
918 	*_got = (uint64_t)lmp;
919 	_got = (uint64_t *)got + M_GOT_XRTLD;
920 	*_got = (uint64_t)elf_rtbndr;
921 }
922 
923 /*
924  * Plt writing interface to allow debugging initialization to be generic.
925  */
926 Pltbindtype
927 /* ARGSUSED1 */
928 elf_plt_write(uintptr_t addr, uintptr_t vaddr, void *rptr, uintptr_t symval,
929 	Xword pltndx)
930 {
931 	Rela		*rel = (Rela*)rptr;
932 	uintptr_t	pltaddr;
933 
934 	pltaddr = addr + rel->r_offset;
935 	*(ulong_t *)pltaddr = (ulong_t)symval + rel->r_addend;
936 	DBG_CALL(pltcntfull++);
937 	return (PLT_T_FULL);
938 }
939 
940 /*
941  * Provide a machine specific interface to the conversion routine.  By calling
942  * the machine specific version, rather than the generic version, we insure that
943  * the data tables/strings for all known machine versions aren't dragged into
944  * ld.so.1.
945  */
946 const char *
947 _conv_reloc_type(uint_t rel)
948 {
949 	static Conv_inv_buf_t	inv_buf;
950 
951 	return (conv_reloc_amd64_type(rel, 0, &inv_buf));
952 }
953