xref: /illumos-gate/usr/src/cmd/sgs/rtld/sparc/sparc_elf.c (revision 257873cfc1dd3337766407f80397db60a56f2f5a)
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 2008 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*
28  *	Copyright (c) 1988 AT&T
29  *	  All Rights Reserved
30  */
31 
32 #pragma ident	"%Z%%M%	%I%	%E% SMI"
33 
34 /*
35  * SPARC machine dependent and ELF file class dependent functions.
36  * Contains routines for performing function binding and symbol relocations.
37  */
38 
39 #include	<stdio.h>
40 #include	<sys/elf.h>
41 #include	<sys/elf_SPARC.h>
42 #include	<sys/mman.h>
43 #include	<dlfcn.h>
44 #include	<synch.h>
45 #include	<string.h>
46 #include	<debug.h>
47 #include	<reloc.h>
48 #include	<conv.h>
49 #include	"_rtld.h"
50 #include	"_audit.h"
51 #include	"_elf.h"
52 #include	"msg.h"
53 
54 
55 extern void	iflush_range(caddr_t, size_t);
56 extern void	plt_full_range(uintptr_t, uintptr_t);
57 
58 
59 int
60 elf_mach_flags_check(Rej_desc *rej, Ehdr *ehdr)
61 {
62 	/*
63 	 * Check machine type and flags.
64 	 */
65 	if (ehdr->e_machine != EM_SPARC) {
66 		if (ehdr->e_machine != EM_SPARC32PLUS) {
67 			rej->rej_type = SGS_REJ_MACH;
68 			rej->rej_info = (uint_t)ehdr->e_machine;
69 			return (0);
70 		}
71 		if ((ehdr->e_flags & EF_SPARC_32PLUS) == 0) {
72 			rej->rej_type = SGS_REJ_MISFLAG;
73 			rej->rej_info = (uint_t)ehdr->e_flags;
74 			return (0);
75 		}
76 		if ((ehdr->e_flags & ~at_flags) & EF_SPARC_32PLUS_MASK) {
77 			rej->rej_type = SGS_REJ_BADFLAG;
78 			rej->rej_info = (uint_t)ehdr->e_flags;
79 			return (0);
80 		}
81 	} else if ((ehdr->e_flags & ~EF_SPARCV9_MM) != 0) {
82 		rej->rej_type = SGS_REJ_BADFLAG;
83 		rej->rej_info = (uint_t)ehdr->e_flags;
84 		return (0);
85 	}
86 	return (1);
87 }
88 
89 void
90 ldso_plt_init(Rt_map * lmp)
91 {
92 	/*
93 	 * There is no need to analyze ld.so because we don't map in any of
94 	 * its dependencies.  However we may map these dependencies in later
95 	 * (as if ld.so had dlopened them), so initialize the plt and the
96 	 * permission information.
97 	 */
98 	if (PLTGOT(lmp))
99 		elf_plt_init((PLTGOT(lmp)), (caddr_t)lmp);
100 }
101 
102 /*
103  * elf_plt_write() will test to see how far away our destination
104  *	address lies.  If it is close enough that a branch can
105  *	be used instead of a jmpl - we will fill the plt in with
106  * 	single branch.  The branches are much quicker then
107  *	a jmpl instruction - see bug#4356879 for further
108  *	details.
109  *
110  *	NOTE: we pass in both a 'pltaddr' and a 'vpltaddr' since
111  *		librtld/dldump update PLT's who's physical
112  *		address is not the same as the 'virtual' runtime
113  *		address.
114  */
115 Pltbindtype
116 /* ARGSUSED4 */
117 elf_plt_write(uintptr_t addr, uintptr_t vaddr, void *rptr, uintptr_t symval,
118 	Xword pltndx)
119 {
120 	Rela		*rel = (Rela *)rptr;
121 	uintptr_t	vpltaddr, pltaddr;
122 	long		disp;
123 
124 
125 	pltaddr = addr + rel->r_offset;
126 	vpltaddr = vaddr + rel->r_offset;
127 	disp = symval - vpltaddr - 4;
128 
129 	/*
130 	 * Test if the destination address is close enough to use
131 	 * a ba,a... instruction to reach it.
132 	 */
133 	if (S_INRANGE(disp, 23) && !(rtld_flags & RT_FL_NOBAPLT)) {
134 		uint_t		*pltent, bainstr;
135 		Pltbindtype	rc;
136 
137 		pltent = (uint_t *)pltaddr;
138 		/*
139 		 * The
140 		 *
141 		 *	ba,a,pt %icc, <dest>
142 		 *
143 		 * is the most efficient of the PLT's.  If we
144 		 * are within +-20 bits *and* running on a
145 		 * v8plus architecture - use that branch.
146 		 */
147 		if ((at_flags & EF_SPARC_32PLUS) &&
148 		    S_INRANGE(disp, 20)) {
149 			bainstr = M_BA_A_PT;	/* ba,a,pt %icc,<dest> */
150 			bainstr |= (S_MASK(19) & (disp >> 2));
151 			rc = PLT_T_21D;
152 			DBG_CALL(pltcnt21d++);
153 		} else {
154 			/*
155 			 * Otherwise - we fall back to the good old
156 			 *
157 			 *	ba,a	<dest>
158 			 *
159 			 * Which still beats a jmpl instruction.
160 			 */
161 			bainstr = M_BA_A;		/* ba,a <dest> */
162 			bainstr |= (S_MASK(22) & (disp >> 2));
163 			rc = PLT_T_24D;
164 			DBG_CALL(pltcnt24d++);
165 		}
166 
167 		pltent[2] = M_NOP;		/* nop instr */
168 		pltent[1] = bainstr;
169 
170 		iflush_range((char *)(&pltent[1]), 4);
171 		pltent[0] = M_NOP;		/* nop instr */
172 		iflush_range((char *)(&pltent[0]), 4);
173 		return (rc);
174 	}
175 
176 	/*
177 	 * The PLT destination is not in reach of
178 	 * a branch instruction - so we fall back
179 	 * to a 'jmpl' sequence.
180 	 */
181 	plt_full_range(pltaddr, symval);
182 	DBG_CALL(pltcntfull++);
183 	return (PLT_T_FULL);
184 }
185 
186 
187 /*
188  * Local storage space created on the stack created for this glue
189  * code includes space for:
190  *		0x4	pointer to dyn_data
191  *		0x4	size prev stack frame
192  */
193 static const uchar_t dyn_plt_template[] = {
194 /* 0x00 */	0x80, 0x90, 0x00, 0x1e,	/* tst   %fp */
195 /* 0x04 */	0x02, 0x80, 0x00, 0x04, /* be    0x14 */
196 /* 0x08 */	0x82, 0x27, 0x80, 0x0e,	/* sub   %sp, %fp, %g1 */
197 /* 0x0c */	0x10, 0x80, 0x00, 0x03, /* ba	 0x20 */
198 /* 0x10 */	0x01, 0x00, 0x00, 0x00, /* nop */
199 /* 0x14 */	0x82, 0x10, 0x20, 0x60, /* mov	0x60, %g1 */
200 /* 0x18 */	0x9d, 0xe3, 0xbf, 0x98,	/* save	%sp, -0x68, %sp */
201 /* 0x1c */	0xc2, 0x27, 0xbf, 0xf8,	/* st	%g1, [%fp + -0x8] */
202 /* 0x20 */	0x03, 0x00, 0x00, 0x00,	/* sethi %hi(val), %g1 */
203 /* 0x24 */	0x82, 0x10, 0x60, 0x00, /* or	 %g1, %lo(val), %g1 */
204 /* 0x28 */	0x40, 0x00, 0x00, 0x00,	/* call  <rel_addr> */
205 /* 0x2c */	0xc2, 0x27, 0xbf, 0xfc	/* st    %g1, [%fp + -0x4] */
206 };
207 
208 int	dyn_plt_ent_size = sizeof (dyn_plt_template) +
209 		sizeof (uintptr_t) +	/* reflmp */
210 		sizeof (uintptr_t) +	/* deflmp */
211 		sizeof (ulong_t) +	/* symndx */
212 		sizeof (ulong_t) +	/* sb_flags */
213 		sizeof (Sym);		/* symdef */
214 
215 /*
216  * the dynamic plt entry is:
217  *
218  *	tst	%fp
219  *	be	1f
220  *	nop
221  *	sub	%sp, %fp, %g1
222  *	ba	2f
223  *	nop
224  * 1:
225  *	mov	SA(MINFRAME), %g1	! if %fp is null this is the
226  *					!   'minimum stack'.  %fp is null
227  *					!   on the initial stack frame
228  * 2:
229  *	save	%sp, -(SA(MINFRAME) + 2 * CLONGSIZE), %sp
230  *	st	%g1, [%fp + -0x8] ! store prev_stack size in [%fp - 8]
231  *	sethi	%hi(dyn_data), %g1
232  *	or	%g1, %lo(dyn_data), %g1
233  *	call	elf_plt_trace
234  *	st	%g1, [%fp + -0x4] ! store dyn_data ptr in [%fp - 4]
235  * dyn data:
236  *	uintptr_t	reflmp
237  *	uintptr_t	deflmp
238  *	ulong_t		symndx
239  *	ulong_t		sb_flags
240  *	Sym		symdef
241  */
242 static caddr_t
243 elf_plt_trace_write(caddr_t addr, Rela *rptr, Rt_map *rlmp, Rt_map *dlmp,
244     Sym *sym, ulong_t symndx, ulong_t pltndx, caddr_t to, ulong_t sb_flags,
245     int *fail)
246 {
247 	extern ulong_t	elf_plt_trace();
248 	uintptr_t	dyn_plt, *dyndata;
249 
250 	/*
251 	 * If both pltenter & pltexit have been disabled there
252 	 * there is no reason to even create the glue code.
253 	 */
254 	if ((sb_flags & (LA_SYMB_NOPLTENTER | LA_SYMB_NOPLTEXIT)) ==
255 	    (LA_SYMB_NOPLTENTER | LA_SYMB_NOPLTEXIT)) {
256 		(void) elf_plt_write((uintptr_t)addr, (uintptr_t)addr,
257 		    rptr, (uintptr_t)to, pltndx);
258 		return (to);
259 	}
260 
261 	/*
262 	 * We only need to add the glue code if there is an auditing
263 	 * library that is interested in this binding.
264 	 */
265 	dyn_plt = (uintptr_t)AUDINFO(rlmp)->ai_dynplts +
266 	    (pltndx * dyn_plt_ent_size);
267 
268 	/*
269 	 * Have we initialized this dynamic plt entry yet?  If we haven't do it
270 	 * now.  Otherwise this function has been called before, but from a
271 	 * different plt (ie. from another shared object).  In that case
272 	 * we just set the plt to point to the new dyn_plt.
273 	 */
274 	if (*(uint_t *)dyn_plt == 0) {
275 		Sym	*symp;
276 		Xword	symvalue;
277 		Lm_list	*lml = LIST(rlmp);
278 
279 		(void) memcpy((void *)dyn_plt, dyn_plt_template,
280 		    sizeof (dyn_plt_template));
281 		dyndata = (uintptr_t *)(dyn_plt + sizeof (dyn_plt_template));
282 
283 		/*
284 		 * relocating:
285 		 *	sethi	%hi(dyndata), %g1
286 		 */
287 		symvalue = (Xword)dyndata;
288 		if (do_reloc_rtld(R_SPARC_HI22, (uchar_t *)(dyn_plt + 0x20),
289 		    &symvalue, MSG_ORIG(MSG_SYM_LADYNDATA),
290 		    MSG_ORIG(MSG_SPECFIL_DYNPLT), lml) == 0) {
291 			*fail = 1;
292 			return (0);
293 		}
294 
295 		/*
296 		 * relocating:
297 		 *	or	%g1, %lo(dyndata), %g1
298 		 */
299 		symvalue = (Xword)dyndata;
300 		if (do_reloc_rtld(R_SPARC_LO10, (uchar_t *)(dyn_plt + 0x24),
301 		    &symvalue, MSG_ORIG(MSG_SYM_LADYNDATA),
302 		    MSG_ORIG(MSG_SPECFIL_DYNPLT), lml) == 0) {
303 			*fail = 1;
304 			return (0);
305 		}
306 
307 		/*
308 		 * relocating:
309 		 *	call	elf_plt_trace
310 		 */
311 		symvalue = (Xword)((uintptr_t)&elf_plt_trace -
312 		    (dyn_plt + 0x28));
313 		if (do_reloc_rtld(R_SPARC_WDISP30, (uchar_t *)(dyn_plt + 0x28),
314 		    &symvalue, MSG_ORIG(MSG_SYM_ELFPLTTRACE),
315 		    MSG_ORIG(MSG_SPECFIL_DYNPLT), lml) == 0) {
316 			*fail = 1;
317 			return (0);
318 		}
319 
320 		*dyndata++ = (uintptr_t)rlmp;
321 		*dyndata++ = (uintptr_t)dlmp;
322 		*(ulong_t *)dyndata++ = symndx;
323 		*(ulong_t *)dyndata++ = sb_flags;
324 		symp = (Sym *)dyndata;
325 		*symp = *sym;
326 		symp->st_name += (Word)STRTAB(dlmp);
327 		symp->st_value = (Addr)to;
328 
329 		iflush_range((void *)dyn_plt, sizeof (dyn_plt_template));
330 	}
331 
332 	(void) elf_plt_write((uintptr_t)addr, (uintptr_t)addr,
333 	    rptr, (uintptr_t)dyn_plt, 0);
334 	return ((caddr_t)dyn_plt);
335 }
336 
337 
338 /*
339  * Function binding routine - invoked on the first call to a function through
340  * the procedure linkage table;
341  * passes first through an assembly language interface.
342  *
343  * Takes the address of the PLT entry where the call originated,
344  * the offset into the relocation table of the associated
345  * relocation entry and the address of the link map (rt_private_map struct)
346  * for the entry.
347  *
348  * Returns the address of the function referenced after re-writing the PLT
349  * entry to invoke the function directly.
350  *
351  * On error, causes process to terminate with a signal.
352  */
353 ulong_t
354 elf_bndr(Rt_map *lmp, ulong_t pltoff, caddr_t from)
355 {
356 	Rt_map		*nlmp, *llmp;
357 	ulong_t		addr, vaddr, reloff, symval, rsymndx;
358 	char		*name;
359 	Rela		*rptr;
360 	Sym		*rsym, *nsym;
361 	Xword		pltndx;
362 	uint_t		binfo, sb_flags = 0;
363 	Slookup		sl;
364 	Pltbindtype	pbtype;
365 	int		entry, lmflags;
366 	uint_t		dbg_class;
367 	Lm_list		*lml = LIST(lmp);
368 
369 	/*
370 	 * For compatibility with libthread (TI_VERSION 1) we track the entry
371 	 * value.  A zero value indicates we have recursed into ld.so.1 to
372 	 * further process a locking request.  Under this recursion we disable
373 	 * tsort and cleanup activities.
374 	 */
375 	entry = enter(0);
376 
377 	if ((lmflags = lml->lm_flags) & LML_FLG_RTLDLM) {
378 		dbg_class = dbg_desc->d_class;
379 		dbg_desc->d_class = 0;
380 	}
381 
382 	/*
383 	 * Must calculate true plt relocation address from reloc.
384 	 * Take offset, subtract number of reserved PLT entries, and divide
385 	 * by PLT entry size, which should give the index of the plt
386 	 * entry (and relocation entry since they have been defined to be
387 	 * in the same order).  Then we must multiply by the size of
388 	 * a relocation entry, which will give us the offset of the
389 	 * plt relocation entry from the start of them given by JMPREL(lm).
390 	 */
391 	addr = pltoff - M_PLT_RESERVSZ;
392 	pltndx = addr / M_PLT_ENTSIZE;
393 
394 	/*
395 	 * Perform some basic sanity checks.  If we didn't get a load map
396 	 * or the plt offset is invalid then its possible someone has walked
397 	 * over the plt entries or jumped to plt0 out of the blue.
398 	 */
399 	if (!lmp || ((addr % M_PLT_ENTSIZE) != 0)) {
400 		Conv_inv_buf_t	inv_buf;
401 
402 		eprintf(lml, ERR_FATAL, MSG_INTL(MSG_REL_PLTREF),
403 		    conv_reloc_SPARC_type(R_SPARC_JMP_SLOT, 0, &inv_buf),
404 		    EC_NATPTR(lmp), EC_XWORD(pltoff), EC_NATPTR(from));
405 		rtldexit(lml, 1);
406 	}
407 	reloff = pltndx * sizeof (Rela);
408 
409 	/*
410 	 * Use relocation entry to get symbol table entry and symbol name.
411 	 */
412 	addr = (ulong_t)JMPREL(lmp);
413 	rptr = (Rela *)(addr + reloff);
414 	rsymndx = ELF_R_SYM(rptr->r_info);
415 	rsym = (Sym *)((ulong_t)SYMTAB(lmp) + (rsymndx * SYMENT(lmp)));
416 	name = (char *)(STRTAB(lmp) + rsym->st_name);
417 
418 	/*
419 	 * Determine the last link-map of this list, this'll be the starting
420 	 * point for any tsort() processing.
421 	 */
422 	llmp = lml->lm_tail;
423 
424 	/*
425 	 * Find definition for symbol.  Initialize the symbol lookup data
426 	 * structure.
427 	 */
428 	SLOOKUP_INIT(sl, name, lmp, lml->lm_head, ld_entry_cnt, 0,
429 	    rsymndx, rsym, 0, LKUP_DEFT);
430 
431 	if ((nsym = lookup_sym(&sl, &nlmp, &binfo, NULL)) == 0) {
432 		eprintf(lml, ERR_FATAL, MSG_INTL(MSG_REL_NOSYM), NAME(lmp),
433 		    demangle(name));
434 		rtldexit(lml, 1);
435 	}
436 
437 	symval = nsym->st_value;
438 	if (!(FLAGS(nlmp) & FLG_RT_FIXED) &&
439 	    (nsym->st_shndx != SHN_ABS))
440 		symval += ADDR(nlmp);
441 	if ((lmp != nlmp) && ((FLAGS1(nlmp) & FL1_RT_NOINIFIN) == 0)) {
442 		/*
443 		 * Record that this new link map is now bound to the caller.
444 		 */
445 		if (bind_one(lmp, nlmp, BND_REFER) == 0)
446 			rtldexit(lml, 1);
447 	}
448 
449 	if ((lml->lm_tflags | FLAGS1(lmp)) & LML_TFLG_AUD_SYMBIND) {
450 		ulong_t	symndx = (((uintptr_t)nsym -
451 		    (uintptr_t)SYMTAB(nlmp)) / SYMENT(nlmp));
452 
453 		symval = audit_symbind(lmp, nlmp, nsym, symndx, symval,
454 		    &sb_flags);
455 	}
456 
457 	if (FLAGS(lmp) & FLG_RT_FIXED)
458 		vaddr = 0;
459 	else
460 		vaddr = ADDR(lmp);
461 
462 	pbtype = PLT_T_NONE;
463 	if (!(rtld_flags & RT_FL_NOBIND)) {
464 		if (((lml->lm_tflags | FLAGS1(lmp)) &
465 		    (LML_TFLG_AUD_PLTENTER | LML_TFLG_AUD_PLTEXIT)) &&
466 		    AUDINFO(lmp)->ai_dynplts) {
467 			int	fail = 0;
468 			ulong_t	symndx = (((uintptr_t)nsym -
469 			    (uintptr_t)SYMTAB(nlmp)) / SYMENT(nlmp));
470 
471 			symval = (ulong_t)elf_plt_trace_write((caddr_t)vaddr,
472 			    rptr, lmp, nlmp, nsym, symndx, pltndx,
473 			    (caddr_t)symval, sb_flags, &fail);
474 			if (fail)
475 				rtldexit(lml, 1);
476 		} else {
477 			/*
478 			 * Write standard PLT entry to jump directly
479 			 * to newly bound function.
480 			 */
481 			pbtype = elf_plt_write((uintptr_t)vaddr,
482 			    (uintptr_t)vaddr, rptr, symval, pltndx);
483 		}
484 	}
485 
486 	/*
487 	 * Print binding information and rebuild PLT entry.
488 	 */
489 	DBG_CALL(Dbg_bind_global(lmp, (Addr)from, (Off)(from - ADDR(lmp)),
490 	    pltndx, pbtype, nlmp, (Addr)symval, nsym->st_value, name, binfo));
491 
492 	/*
493 	 * Complete any processing for newly loaded objects.  Note we don't
494 	 * know exactly where any new objects are loaded (we know the object
495 	 * that supplied the symbol, but others may have been loaded lazily as
496 	 * we searched for the symbol), so sorting starts from the last
497 	 * link-map know on entry to this routine.
498 	 */
499 	if (entry)
500 		load_completion(llmp);
501 
502 	/*
503 	 * Some operations like dldump() or dlopen()'ing a relocatable object
504 	 * result in objects being loaded on rtld's link-map, make sure these
505 	 * objects are initialized also.
506 	 */
507 	if ((LIST(nlmp)->lm_flags & LML_FLG_RTLDLM) && LIST(nlmp)->lm_init)
508 		load_completion(nlmp);
509 
510 	/*
511 	 * If the object we've bound to is in the process of being initialized
512 	 * by another thread, determine whether we should block.
513 	 */
514 	is_dep_ready(nlmp, lmp, DBG_WAIT_SYMBOL);
515 
516 	/*
517 	 * Make sure the object to which we've bound has had it's .init fired.
518 	 * Cleanup before return to user code.
519 	 */
520 	if (entry) {
521 		is_dep_init(nlmp, lmp);
522 		leave(lml, 0);
523 	}
524 
525 	if (lmflags & LML_FLG_RTLDLM)
526 		dbg_desc->d_class = dbg_class;
527 
528 	return (symval);
529 }
530 
531 
532 /*
533  * Read and process the relocations for one link object, we assume all
534  * relocation sections for loadable segments are stored contiguously in
535  * the file.
536  */
537 int
538 elf_reloc(Rt_map *lmp, uint_t plt, int *in_nfavl)
539 {
540 	ulong_t		relbgn, relend, relsiz, basebgn, pltbgn, pltend;
541 	ulong_t		roffset, rsymndx, psymndx = 0, etext = ETEXT(lmp);
542 	ulong_t		emap, dsymndx, pltndx;
543 	uchar_t		rtype;
544 	long		reladd, value, pvalue;
545 	Sym		*symref, *psymref, *symdef, *psymdef;
546 	char		*name, *pname;
547 	Rt_map		*_lmp, *plmp;
548 	int		textrel = 0, ret = 1, noplt = 0;
549 	long		relacount = RELACOUNT(lmp);
550 	Rela		*rel;
551 	Pltbindtype	pbtype;
552 	uint_t		binfo, pbinfo;
553 	APlist		*bound = NULL;
554 
555 	/*
556 	 * If an object has any DT_REGISTER entries associated with
557 	 * it, they are processed now.
558 	 */
559 	if ((plt == 0) && (FLAGS(lmp) & FLG_RT_REGSYMS)) {
560 		if (elf_regsyms(lmp) == 0)
561 			return (0);
562 	}
563 
564 	/*
565 	 * Although only necessary for lazy binding, initialize the first
566 	 * procedure linkage table entry to go to elf_rtbndr().  dbx(1) seems
567 	 * to find this useful.
568 	 */
569 	if ((plt == 0) && PLTGOT(lmp)) {
570 		if ((ulong_t)PLTGOT(lmp) < etext) {
571 			if (elf_set_prot(lmp, PROT_WRITE) == 0)
572 				return (0);
573 			textrel = 1;
574 		}
575 		elf_plt_init(PLTGOT(lmp), (caddr_t)lmp);
576 	}
577 
578 	/*
579 	 * Initialize the plt start and end addresses.
580 	 */
581 	if ((pltbgn = (ulong_t)JMPREL(lmp)) != 0)
582 		pltend = pltbgn + (ulong_t)(PLTRELSZ(lmp));
583 
584 	/*
585 	 * If we've been called upon to promote an RTLD_LAZY object to an
586 	 * RTLD_NOW then we're only interested in scaning the .plt table.
587 	 */
588 	if (plt) {
589 		relbgn = pltbgn;
590 		relend = pltend;
591 	} else {
592 		/*
593 		 * The relocation sections appear to the run-time linker as a
594 		 * single table.  Determine the address of the beginning and end
595 		 * of this table.  There are two different interpretations of
596 		 * the ABI at this point:
597 		 *
598 		 *   o	The REL table and its associated RELSZ indicate the
599 		 *	concatenation of *all* relocation sections (this is the
600 		 *	model our link-editor constructs).
601 		 *
602 		 *   o	The REL table and its associated RELSZ indicate the
603 		 *	concatenation of all *but* the .plt relocations.  These
604 		 *	relocations are specified individually by the JMPREL and
605 		 *	PLTRELSZ entries.
606 		 *
607 		 * Determine from our knowledege of the relocation range and
608 		 * .plt range, the range of the total relocation table.  Note
609 		 * that one other ABI assumption seems to be that the .plt
610 		 * relocations always follow any other relocations, the
611 		 * following range checking drops that assumption.
612 		 */
613 		relbgn = (ulong_t)(REL(lmp));
614 		relend = relbgn + (ulong_t)(RELSZ(lmp));
615 		if (pltbgn) {
616 			if (!relbgn || (relbgn > pltbgn))
617 				relbgn = pltbgn;
618 			if (!relbgn || (relend < pltend))
619 				relend = pltend;
620 		}
621 	}
622 	if (!relbgn || (relbgn == relend)) {
623 		DBG_CALL(Dbg_reloc_run(lmp, 0, plt, DBG_REL_NONE));
624 		return (1);
625 	}
626 
627 	relsiz = (ulong_t)(RELENT(lmp));
628 	basebgn = ADDR(lmp);
629 	emap = ADDR(lmp) + MSIZE(lmp);
630 
631 	DBG_CALL(Dbg_reloc_run(lmp, M_REL_SHT_TYPE, plt, DBG_REL_START));
632 
633 	/*
634 	 * If we're processing in lazy mode there is no need to scan the
635 	 * .rela.plt table.
636 	 */
637 	if (pltbgn && ((MODE(lmp) & RTLD_NOW) == 0))
638 		noplt = 1;
639 
640 	/*
641 	 * Loop through relocations.
642 	 */
643 	while (relbgn < relend) {
644 		Addr		vaddr;
645 		uint_t		sb_flags = 0;
646 
647 		rtype = ELF_R_TYPE(((Rela *)relbgn)->r_info, M_MACH);
648 
649 		/*
650 		 * If this is a RELATIVE relocation in a shared object (the
651 		 * common case), and if we are not debugging, then jump into a
652 		 * tighter relocation loop (elf_reloc_relative).  Only make the
653 		 * jump if we've been given a hint on the number of relocations.
654 		 */
655 		if ((rtype == R_SPARC_RELATIVE) &&
656 		    ((FLAGS(lmp) & FLG_RT_FIXED) == 0) && (DBG_ENABLED == 0)) {
657 			/*
658 			 * It's possible that the relative relocation block
659 			 * has relocations against the text segment as well
660 			 * as the data segment.  Since our optimized relocation
661 			 * engine does not check which segment the relocation
662 			 * is against - just mprotect it now if it's been
663 			 * marked as containing TEXTREL's.
664 			 */
665 			if ((textrel == 0) && (FLAGS1(lmp) & FL1_RT_TEXTREL)) {
666 				if (elf_set_prot(lmp, PROT_WRITE) == 0) {
667 					ret = 0;
668 					break;
669 				}
670 				textrel = 1;
671 			}
672 			if (relacount) {
673 				relbgn = elf_reloc_relacount(relbgn, relacount,
674 				    relsiz, basebgn);
675 				relacount = 0;
676 			} else {
677 				relbgn = elf_reloc_relative(relbgn, relend,
678 				    relsiz, basebgn, etext, emap);
679 			}
680 			if (relbgn >= relend)
681 				break;
682 			rtype = ELF_R_TYPE(((Rela *)relbgn)->r_info, M_MACH);
683 		}
684 
685 		roffset = ((Rela *)relbgn)->r_offset;
686 
687 		reladd = (long)(((Rela *)relbgn)->r_addend);
688 		rsymndx = ELF_R_SYM(((Rela *)relbgn)->r_info);
689 
690 		rel = (Rela *)relbgn;
691 		relbgn += relsiz;
692 
693 		/*
694 		 * Optimizations.
695 		 */
696 		if (rtype == R_SPARC_NONE)
697 			continue;
698 		if (noplt && ((ulong_t)rel >= pltbgn) &&
699 		    ((ulong_t)rel < pltend)) {
700 			relbgn = pltend;
701 			continue;
702 		}
703 
704 		if (rtype != R_SPARC_REGISTER) {
705 			/*
706 			 * If this is a shared object, add the base address
707 			 * to offset.
708 			 */
709 			if (!(FLAGS(lmp) & FLG_RT_FIXED))
710 				roffset += basebgn;
711 
712 			/*
713 			 * If this relocation is not against part of the image
714 			 * mapped into memory we skip it.
715 			 */
716 			if ((roffset < ADDR(lmp)) || (roffset > (ADDR(lmp) +
717 			    MSIZE(lmp)))) {
718 				elf_reloc_bad(lmp, (void *)rel, rtype, roffset,
719 				    rsymndx);
720 				continue;
721 			}
722 		}
723 
724 		/*
725 		 * If we're promoting .plts try and determine if this one has
726 		 * already been written.  An uninitialized .plts' second
727 		 * instruction is a branch.  Note, elf_plt_write() optimizes
728 		 * .plt relocations, and it's possible that a relocated entry
729 		 * is a branch.  If this is the case, we can't tell the
730 		 * difference between an uninitialized .plt and a relocated,
731 		 * .plt that uses a branch.  In this case, we'll simply redo
732 		 * the relocation calculation, which is a bit sad.
733 		 */
734 		if (plt) {
735 			ulong_t	*_roffset = (ulong_t *)roffset;
736 
737 			_roffset++;
738 			if ((*_roffset & (~(S_MASK(22)))) != M_BA_A)
739 				continue;
740 		}
741 
742 		binfo = 0;
743 		pltndx = (ulong_t)-1;
744 		pbtype = PLT_T_NONE;
745 		/*
746 		 * If a symbol index is specified then get the symbol table
747 		 * entry, locate the symbol definition, and determine its
748 		 * address.
749 		 */
750 		if (rsymndx) {
751 			/*
752 			 * Get the local symbol table entry.
753 			 */
754 			symref = (Sym *)((ulong_t)SYMTAB(lmp) +
755 			    (rsymndx * SYMENT(lmp)));
756 
757 			/*
758 			 * If this is a local symbol, just use the base address.
759 			 * (we should have no local relocations in the
760 			 * executable).
761 			 */
762 			if (ELF_ST_BIND(symref->st_info) == STB_LOCAL) {
763 				value = basebgn;
764 				name = (char *)0;
765 
766 				/*
767 				 * Special case TLS relocations.
768 				 */
769 				if (rtype == R_SPARC_TLS_DTPMOD32) {
770 					/*
771 					 * Use the TLS modid.
772 					 */
773 					value = TLSMODID(lmp);
774 
775 				} else if (rtype == R_SPARC_TLS_TPOFF32) {
776 					if ((value = elf_static_tls(lmp, symref,
777 					    rel, rtype, 0, roffset, 0)) == 0) {
778 						ret = 0;
779 						break;
780 					}
781 				}
782 			} else {
783 				/*
784 				 * If the symbol index is equal to the previous
785 				 * symbol index relocation we processed then
786 				 * reuse the previous values. (Note that there
787 				 * have been cases where a relocation exists
788 				 * against a copy relocation symbol, our ld(1)
789 				 * should optimize this away, but make sure we
790 				 * don't use the same symbol information should
791 				 * this case exist).
792 				 */
793 				if ((rsymndx == psymndx) &&
794 				    (rtype != R_SPARC_COPY)) {
795 					/* LINTED */
796 					if (psymdef == 0) {
797 						DBG_CALL(Dbg_bind_weak(lmp,
798 						    (Addr)roffset, (Addr)
799 						    (roffset - basebgn), name));
800 						continue;
801 					}
802 					/* LINTED */
803 					value = pvalue;
804 					/* LINTED */
805 					name = pname;
806 					symdef = psymdef;
807 					/* LINTED */
808 					symref = psymref;
809 					/* LINTED */
810 					_lmp = plmp;
811 					/* LINTED */
812 					binfo = pbinfo;
813 
814 					if ((LIST(_lmp)->lm_tflags |
815 					    FLAGS1(_lmp)) &
816 					    LML_TFLG_AUD_SYMBIND) {
817 						value = audit_symbind(lmp, _lmp,
818 						    /* LINTED */
819 						    symdef, dsymndx, value,
820 						    &sb_flags);
821 					}
822 				} else {
823 					Slookup		sl;
824 
825 					/*
826 					 * Lookup the symbol definition.
827 					 * Initialize the symbol lookup data
828 					 * structure.
829 					 */
830 					name = (char *)(STRTAB(lmp) +
831 					    symref->st_name);
832 
833 					SLOOKUP_INIT(sl, name, lmp, 0,
834 					    ld_entry_cnt, 0, rsymndx, symref,
835 					    rtype, LKUP_STDRELOC);
836 
837 					symdef = lookup_sym(&sl, &_lmp,
838 					    &binfo, in_nfavl);
839 
840 					/*
841 					 * If the symbol is not found and the
842 					 * reference was not to a weak symbol,
843 					 * report an error.  Weak references
844 					 * may be unresolved.
845 					 */
846 					/* BEGIN CSTYLED */
847 					if (symdef == 0) {
848 					    if (sl.sl_bind != STB_WEAK) {
849 						if (elf_reloc_error(lmp, name,
850 						    rel, binfo))
851 							continue;
852 
853 						ret = 0;
854 						break;
855 
856 					    } else {
857 						psymndx = rsymndx;
858 						psymdef = 0;
859 
860 						DBG_CALL(Dbg_bind_weak(lmp,
861 						    (Addr)roffset, (Addr)
862 						    (roffset - basebgn), name));
863 						continue;
864 					    }
865 					}
866 					/* END CSTYLED */
867 
868 					/*
869 					 * If symbol was found in an object
870 					 * other than the referencing object
871 					 * then record the binding.
872 					 */
873 					if ((lmp != _lmp) && ((FLAGS1(_lmp) &
874 					    FL1_RT_NOINIFIN) == 0)) {
875 						if (aplist_test(&bound, _lmp,
876 						    AL_CNT_RELBIND) == 0) {
877 							ret = 0;
878 							break;
879 						}
880 					}
881 
882 					/*
883 					 * Calculate the location of definition;
884 					 * symbol value plus base address of
885 					 * containing shared object.
886 					 */
887 					if (IS_SIZE(rtype))
888 						value = symdef->st_size;
889 					else
890 						value = symdef->st_value;
891 
892 					if (!(FLAGS(_lmp) & FLG_RT_FIXED) &&
893 					    !(IS_SIZE(rtype)) &&
894 					    (symdef->st_shndx != SHN_ABS) &&
895 					    (ELF_ST_TYPE(symdef->st_info) !=
896 					    STT_TLS))
897 						value += ADDR(_lmp);
898 
899 					/*
900 					 * Retain this symbol index and the
901 					 * value in case it can be used for the
902 					 * subsequent relocations.
903 					 */
904 					if (rtype != R_SPARC_COPY) {
905 						psymndx = rsymndx;
906 						pvalue = value;
907 						pname = name;
908 						psymdef = symdef;
909 						psymref = symref;
910 						plmp = _lmp;
911 						pbinfo = binfo;
912 					}
913 					if ((LIST(_lmp)->lm_tflags |
914 					    FLAGS1(_lmp)) &
915 					    LML_TFLG_AUD_SYMBIND) {
916 						dsymndx = (((uintptr_t)symdef -
917 						    (uintptr_t)SYMTAB(_lmp)) /
918 						    SYMENT(_lmp));
919 						value = audit_symbind(lmp, _lmp,
920 						    symdef, dsymndx, value,
921 						    &sb_flags);
922 					}
923 				}
924 
925 				/*
926 				 * If relocation is PC-relative, subtract
927 				 * offset address.
928 				 */
929 				if (IS_PC_RELATIVE(rtype))
930 					value -= roffset;
931 
932 				/*
933 				 * Special case TLS relocations.
934 				 */
935 				if (rtype == R_SPARC_TLS_DTPMOD32) {
936 					/*
937 					 * Relocation value is the TLS modid.
938 					 */
939 					value = TLSMODID(_lmp);
940 
941 				} else if (rtype == R_SPARC_TLS_TPOFF32) {
942 					if ((value = elf_static_tls(_lmp,
943 					    symdef, rel, rtype, name, roffset,
944 					    value)) == 0) {
945 						ret = 0;
946 						break;
947 					}
948 				}
949 			}
950 		} else {
951 			/*
952 			 * Special cases.
953 			 */
954 			if (rtype == R_SPARC_REGISTER) {
955 				/*
956 				 * A register symbol associated with symbol
957 				 * index 0 is initialized (i.e. relocated) to
958 				 * a constant in the r_addend field rather than
959 				 * to a symbol value.
960 				 */
961 				value = 0;
962 
963 			} else if (rtype == R_SPARC_TLS_DTPMOD32) {
964 				/*
965 				 * TLS relocation value is the TLS modid.
966 				 */
967 				value = TLSMODID(lmp);
968 			} else
969 				value = basebgn;
970 			name = (char *)0;
971 		}
972 
973 		DBG_CALL(Dbg_reloc_in(LIST(lmp), ELF_DBG_RTLD, M_MACH,
974 		    M_REL_SHT_TYPE, rel, NULL, name));
975 
976 		/*
977 		 * If this object has relocations in the text segment, turn
978 		 * off the write protect.
979 		 */
980 		if ((rtype != R_SPARC_REGISTER) && (roffset < etext) &&
981 		    (textrel == 0)) {
982 			if (elf_set_prot(lmp, PROT_WRITE) == 0) {
983 				ret = 0;
984 				break;
985 			}
986 			textrel = 1;
987 		}
988 
989 		/*
990 		 * Call relocation routine to perform required relocation.
991 		 */
992 		switch (rtype) {
993 		case R_SPARC_REGISTER:
994 			/*
995 			 * The v9 ABI 4.2.4 says that system objects may,
996 			 * but are not required to, use register symbols
997 			 * to inidcate how they use global registers. Thus
998 			 * at least %g6, %g7 must be allowed in addition
999 			 * to %g2 and %g3.
1000 			 */
1001 			value += reladd;
1002 			if (roffset == STO_SPARC_REGISTER_G1) {
1003 				set_sparc_g1(value);
1004 			} else if (roffset == STO_SPARC_REGISTER_G2) {
1005 				set_sparc_g2(value);
1006 			} else if (roffset == STO_SPARC_REGISTER_G3) {
1007 				set_sparc_g3(value);
1008 			} else if (roffset == STO_SPARC_REGISTER_G4) {
1009 				set_sparc_g4(value);
1010 			} else if (roffset == STO_SPARC_REGISTER_G5) {
1011 				set_sparc_g5(value);
1012 			} else if (roffset == STO_SPARC_REGISTER_G6) {
1013 				set_sparc_g6(value);
1014 			} else if (roffset == STO_SPARC_REGISTER_G7) {
1015 				set_sparc_g7(value);
1016 			} else {
1017 				eprintf(LIST(lmp), ERR_FATAL,
1018 				    MSG_INTL(MSG_REL_BADREG), NAME(lmp),
1019 				    EC_ADDR(roffset));
1020 				ret = 0;
1021 				break;
1022 			}
1023 
1024 			DBG_CALL(Dbg_reloc_apply_reg(LIST(lmp), ELF_DBG_RTLD,
1025 			    M_MACH, (Xword)roffset, (Xword)value));
1026 			break;
1027 		case R_SPARC_COPY:
1028 			if (elf_copy_reloc(name, symref, lmp, (void *)roffset,
1029 			    symdef, _lmp, (const void *)value) == 0)
1030 				ret = 0;
1031 			break;
1032 		case R_SPARC_JMP_SLOT:
1033 			pltndx = ((ulong_t)rel -
1034 			    (uintptr_t)JMPREL(lmp)) / relsiz;
1035 
1036 			if (FLAGS(lmp) & FLG_RT_FIXED)
1037 				vaddr = 0;
1038 			else
1039 				vaddr = ADDR(lmp);
1040 
1041 			if (((LIST(lmp)->lm_tflags | FLAGS1(lmp)) &
1042 			    (LML_TFLG_AUD_PLTENTER | LML_TFLG_AUD_PLTEXIT)) &&
1043 			    AUDINFO(lmp)->ai_dynplts) {
1044 				int	fail = 0;
1045 				ulong_t	symndx = (((uintptr_t)symdef -
1046 				    (uintptr_t)SYMTAB(_lmp)) / SYMENT(_lmp));
1047 
1048 				(void) elf_plt_trace_write((caddr_t)vaddr,
1049 				    (Rela *)rel, lmp, _lmp, symdef, symndx,
1050 				    pltndx, (caddr_t)value, sb_flags, &fail);
1051 				if (fail)
1052 					ret = 0;
1053 			} else {
1054 				/*
1055 				 * Write standard PLT entry to jump directly
1056 				 * to newly bound function.
1057 				 */
1058 				DBG_CALL(Dbg_reloc_apply_val(LIST(lmp),
1059 				    ELF_DBG_RTLD, (Xword)roffset,
1060 				    (Xword)value));
1061 				pbtype = elf_plt_write((uintptr_t)vaddr,
1062 				    (uintptr_t)vaddr, (void *)rel, value,
1063 				    pltndx);
1064 			}
1065 			break;
1066 		default:
1067 			value += reladd;
1068 
1069 			/*
1070 			 * Write the relocation out.  If this relocation is a
1071 			 * common basic write, skip the doreloc() engine.
1072 			 */
1073 			if ((rtype == R_SPARC_GLOB_DAT) ||
1074 			    (rtype == R_SPARC_32)) {
1075 				if (roffset & 0x3) {
1076 					Conv_inv_buf_t inv_buf;
1077 
1078 					eprintf(LIST(lmp), ERR_FATAL,
1079 					    MSG_INTL(MSG_REL_NONALIGN),
1080 					    conv_reloc_SPARC_type(rtype,
1081 					    0, &inv_buf),
1082 					    NAME(lmp), demangle(name),
1083 					    EC_OFF(roffset));
1084 					ret = 0;
1085 				} else
1086 					*(uint_t *)roffset += value;
1087 			} else {
1088 				if (do_reloc_rtld(rtype, (uchar_t *)roffset,
1089 				    (Xword *)&value, name,
1090 				    NAME(lmp), LIST(lmp)) == 0)
1091 					ret = 0;
1092 			}
1093 
1094 			/*
1095 			 * The value now contains the 'bit-shifted' value that
1096 			 * was or'ed into memory (this was set by
1097 			 * do_reloc_rtld()).
1098 			 */
1099 			DBG_CALL(Dbg_reloc_apply_val(LIST(lmp), ELF_DBG_RTLD,
1100 			    (Xword)roffset, (Xword)value));
1101 
1102 			/*
1103 			 * If this relocation is against a text segment, make
1104 			 * sure that the instruction cache is flushed.
1105 			 */
1106 			if (textrel)
1107 				iflush_range((caddr_t)roffset, 0x4);
1108 		}
1109 
1110 		if ((ret == 0) &&
1111 		    ((LIST(lmp)->lm_flags & LML_FLG_TRC_WARN) == 0))
1112 			break;
1113 
1114 		if (binfo) {
1115 			DBG_CALL(Dbg_bind_global(lmp, (Addr)roffset,
1116 			    (Off)(roffset - basebgn), pltndx, pbtype,
1117 			    _lmp, (Addr)value, symdef->st_value, name, binfo));
1118 		}
1119 	}
1120 
1121 	return (relocate_finish(lmp, bound, textrel, ret));
1122 }
1123 
1124 /*
1125  * Provide a machine specific interface to the conversion routine.  By calling
1126  * the machine specific version, rather than the generic version, we insure that
1127  * the data tables/strings for all known machine versions aren't dragged into
1128  * ld.so.1.
1129  */
1130 const char *
1131 _conv_reloc_type(uint_t rel)
1132 {
1133 	static Conv_inv_buf_t	inv_buf;
1134 
1135 	return (conv_reloc_SPARC_type(rel, 0, &inv_buf));
1136 }
1137