xref: /illumos-gate/usr/src/cmd/sgs/rtld/sparc/sparc_elf.c (revision 3d63ea05)
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 2007 Sun Microsystems, Inc.  All rights reserved.
27  * Use is subject to license terms.
28  */
29 #pragma ident	"%Z%%M%	%I%	%E% SMI"
30 
31 /*
32  * SPARC machine dependent and ELF file class dependent functions.
33  * Contains routines for performing function binding and symbol relocations.
34  */
35 #include	"_synonyms.h"
36 
37 #include	<stdio.h>
38 #include	<sys/elf.h>
39 #include	<sys/elf_SPARC.h>
40 #include	<sys/mman.h>
41 #include	<dlfcn.h>
42 #include	<synch.h>
43 #include	<string.h>
44 #include	<debug.h>
45 #include	<reloc.h>
46 #include	<conv.h>
47 #include	"_rtld.h"
48 #include	"_audit.h"
49 #include	"_elf.h"
50 #include	"msg.h"
51 
52 
53 extern void	iflush_range(caddr_t, size_t);
54 extern void	plt_full_range(uintptr_t, uintptr_t);
55 
56 
57 int
58 elf_mach_flags_check(Rej_desc *rej, Ehdr *ehdr)
59 {
60 	/*
61 	 * Check machine type and flags.
62 	 */
63 	if (ehdr->e_machine != EM_SPARC) {
64 		if (ehdr->e_machine != EM_SPARC32PLUS) {
65 			rej->rej_type = SGS_REJ_MACH;
66 			rej->rej_info = (uint_t)ehdr->e_machine;
67 			return (0);
68 		}
69 		if ((ehdr->e_flags & EF_SPARC_32PLUS) == 0) {
70 			rej->rej_type = SGS_REJ_MISFLAG;
71 			rej->rej_info = (uint_t)ehdr->e_flags;
72 			return (0);
73 		}
74 		if ((ehdr->e_flags & ~at_flags) & EF_SPARC_32PLUS_MASK) {
75 			rej->rej_type = SGS_REJ_BADFLAG;
76 			rej->rej_info = (uint_t)ehdr->e_flags;
77 			return (0);
78 		}
79 	} else if ((ehdr->e_flags & ~EF_SPARCV9_MM) != 0) {
80 		rej->rej_type = SGS_REJ_BADFLAG;
81 		rej->rej_info = (uint_t)ehdr->e_flags;
82 		return (0);
83 	}
84 	return (1);
85 }
86 
87 void
88 ldso_plt_init(Rt_map * lmp)
89 {
90 	/*
91 	 * There is no need to analyze ld.so because we don't map in any of
92 	 * its dependencies.  However we may map these dependencies in later
93 	 * (as if ld.so had dlopened them), so initialize the plt and the
94 	 * permission information.
95 	 */
96 	if (PLTGOT(lmp))
97 		elf_plt_init((PLTGOT(lmp)), (caddr_t)lmp);
98 }
99 
100 /*
101  * elf_plt_write() will test to see how far away our destination
102  *	address lies.  If it is close enough that a branch can
103  *	be used instead of a jmpl - we will fill the plt in with
104  * 	single branch.  The branches are much quicker then
105  *	a jmpl instruction - see bug#4356879 for further
106  *	details.
107  *
108  *	NOTE: we pass in both a 'pltaddr' and a 'vpltaddr' since
109  *		librtld/dldump update PLT's who's physical
110  *		address is not the same as the 'virtual' runtime
111  *		address.
112  */
113 Pltbindtype
114 /* ARGSUSED4 */
115 elf_plt_write(uintptr_t addr, uintptr_t vaddr, void *rptr, uintptr_t symval,
116 	Xword pltndx)
117 {
118 	Rela		*rel = (Rela *)rptr;
119 	uintptr_t	vpltaddr, pltaddr;
120 	long		disp;
121 
122 
123 	pltaddr = addr + rel->r_offset;
124 	vpltaddr = vaddr + rel->r_offset;
125 	disp = symval - vpltaddr - 4;
126 
127 	/*
128 	 * Test if the destination address is close enough to use
129 	 * a ba,a... instruction to reach it.
130 	 */
131 	if (S_INRANGE(disp, 23) && !(rtld_flags & RT_FL_NOBAPLT)) {
132 		uint_t		*pltent, bainstr;
133 		Pltbindtype	rc;
134 
135 		pltent = (uint_t *)pltaddr;
136 		/*
137 		 * The
138 		 *
139 		 *	ba,a,pt %icc, <dest>
140 		 *
141 		 * is the most efficient of the PLT's.  If we
142 		 * are within +-20 bits *and* running on a
143 		 * v8plus architecture - use that branch.
144 		 */
145 		if ((at_flags & EF_SPARC_32PLUS) &&
146 		    S_INRANGE(disp, 20)) {
147 			bainstr = M_BA_A_PT;	/* ba,a,pt %icc,<dest> */
148 			bainstr |= (S_MASK(19) & (disp >> 2));
149 			rc = PLT_T_21D;
150 			DBG_CALL(pltcnt21d++);
151 		} else {
152 			/*
153 			 * Otherwise - we fall back to the good old
154 			 *
155 			 *	ba,a	<dest>
156 			 *
157 			 * Which still beats a jmpl instruction.
158 			 */
159 			bainstr = M_BA_A;		/* ba,a <dest> */
160 			bainstr |= (S_MASK(22) & (disp >> 2));
161 			rc = PLT_T_24D;
162 			DBG_CALL(pltcnt24d++);
163 		}
164 
165 		pltent[2] = M_NOP;		/* nop instr */
166 		pltent[1] = bainstr;
167 
168 		iflush_range((char *)(&pltent[1]), 4);
169 		pltent[0] = M_NOP;		/* nop instr */
170 		iflush_range((char *)(&pltent[0]), 4);
171 		return (rc);
172 	}
173 
174 	/*
175 	 * The PLT destination is not in reach of
176 	 * a branch instruction - so we fall back
177 	 * to a 'jmpl' sequence.
178 	 */
179 	plt_full_range(pltaddr, symval);
180 	DBG_CALL(pltcntfull++);
181 	return (PLT_T_FULL);
182 }
183 
184 
185 /*
186  * Local storage space created on the stack created for this glue
187  * code includes space for:
188  *		0x4	pointer to dyn_data
189  *		0x4	size prev stack frame
190  */
191 static const uchar_t dyn_plt_template[] = {
192 /* 0x00 */	0x80, 0x90, 0x00, 0x1e,	/* tst   %fp */
193 /* 0x04 */	0x02, 0x80, 0x00, 0x04, /* be    0x14 */
194 /* 0x08 */	0x82, 0x27, 0x80, 0x0e,	/* sub   %sp, %fp, %g1 */
195 /* 0x0c */	0x10, 0x80, 0x00, 0x03, /* ba	 0x20 */
196 /* 0x10 */	0x01, 0x00, 0x00, 0x00, /* nop */
197 /* 0x14 */	0x82, 0x10, 0x20, 0x60, /* mov	0x60, %g1 */
198 /* 0x18 */	0x9d, 0xe3, 0xbf, 0x98,	/* save	%sp, -0x68, %sp */
199 /* 0x1c */	0xc2, 0x27, 0xbf, 0xf8,	/* st	%g1, [%fp + -0x8] */
200 /* 0x20 */	0x03, 0x00, 0x00, 0x00,	/* sethi %hi(val), %g1 */
201 /* 0x24 */	0x82, 0x10, 0x60, 0x00, /* or	 %g1, %lo(val), %g1 */
202 /* 0x28 */	0x40, 0x00, 0x00, 0x00,	/* call  <rel_addr> */
203 /* 0x2c */	0xc2, 0x27, 0xbf, 0xfc	/* st    %g1, [%fp + -0x4] */
204 };
205 
206 int	dyn_plt_ent_size = sizeof (dyn_plt_template) +
207 		sizeof (uintptr_t) +	/* reflmp */
208 		sizeof (uintptr_t) +	/* deflmp */
209 		sizeof (ulong_t) +	/* symndx */
210 		sizeof (ulong_t) +	/* sb_flags */
211 		sizeof (Sym);		/* symdef */
212 
213 /*
214  * the dynamic plt entry is:
215  *
216  *	tst	%fp
217  *	be	1f
218  *	nop
219  *	sub	%sp, %fp, %g1
220  *	ba	2f
221  *	nop
222  * 1:
223  *	mov	SA(MINFRAME), %g1	! if %fp is null this is the
224  *					!   'minimum stack'.  %fp is null
225  *					!   on the initial stack frame
226  * 2:
227  *	save	%sp, -(SA(MINFRAME) + 2 * CLONGSIZE), %sp
228  *	st	%g1, [%fp + -0x8] ! store prev_stack size in [%fp - 8]
229  *	sethi	%hi(dyn_data), %g1
230  *	or	%g1, %lo(dyn_data), %g1
231  *	call	elf_plt_trace
232  *	st	%g1, [%fp + -0x4] ! store dyn_data ptr in [%fp - 4]
233  * dyn data:
234  *	uintptr_t	reflmp
235  *	uintptr_t	deflmp
236  *	ulong_t		symndx
237  *	ulong_t		sb_flags
238  *	Sym		symdef
239  */
240 static caddr_t
241 elf_plt_trace_write(caddr_t addr, Rela *rptr, Rt_map *rlmp, Rt_map *dlmp,
242     Sym *sym, ulong_t symndx, ulong_t pltndx, caddr_t to, ulong_t sb_flags,
243     int *fail)
244 {
245 	extern ulong_t	elf_plt_trace();
246 	uintptr_t	dyn_plt, *dyndata;
247 
248 	/*
249 	 * If both pltenter & pltexit have been disabled there
250 	 * there is no reason to even create the glue code.
251 	 */
252 	if ((sb_flags & (LA_SYMB_NOPLTENTER | LA_SYMB_NOPLTEXIT)) ==
253 	    (LA_SYMB_NOPLTENTER | LA_SYMB_NOPLTEXIT)) {
254 		(void) elf_plt_write((uintptr_t)addr, (uintptr_t)addr,
255 		    rptr, (uintptr_t)to, pltndx);
256 		return (to);
257 	}
258 
259 	/*
260 	 * We only need to add the glue code if there is an auditing
261 	 * library that is interested in this binding.
262 	 */
263 	dyn_plt = (uintptr_t)AUDINFO(rlmp)->ai_dynplts +
264 	    (pltndx * dyn_plt_ent_size);
265 
266 	/*
267 	 * Have we initialized this dynamic plt entry yet?  If we haven't do it
268 	 * now.  Otherwise this function has been called before, but from a
269 	 * different plt (ie. from another shared object).  In that case
270 	 * we just set the plt to point to the new dyn_plt.
271 	 */
272 	if (*(uint_t *)dyn_plt == 0) {
273 		Sym	*symp;
274 		Xword	symvalue;
275 		Lm_list	*lml = LIST(rlmp);
276 
277 		(void) memcpy((void *)dyn_plt, dyn_plt_template,
278 		    sizeof (dyn_plt_template));
279 		dyndata = (uintptr_t *)(dyn_plt + sizeof (dyn_plt_template));
280 
281 		/*
282 		 * relocating:
283 		 *	sethi	%hi(dyndata), %g1
284 		 */
285 		symvalue = (Xword)dyndata;
286 		if (do_reloc(R_SPARC_HI22, (uchar_t *)(dyn_plt + 0x20),
287 		    &symvalue, MSG_ORIG(MSG_SYM_LADYNDATA),
288 		    MSG_ORIG(MSG_SPECFIL_DYNPLT), lml) == 0) {
289 			*fail = 1;
290 			return (0);
291 		}
292 
293 		/*
294 		 * relocating:
295 		 *	or	%g1, %lo(dyndata), %g1
296 		 */
297 		symvalue = (Xword)dyndata;
298 		if (do_reloc(R_SPARC_LO10, (uchar_t *)(dyn_plt + 0x24),
299 		    &symvalue, MSG_ORIG(MSG_SYM_LADYNDATA),
300 		    MSG_ORIG(MSG_SPECFIL_DYNPLT), lml) == 0) {
301 			*fail = 1;
302 			return (0);
303 		}
304 
305 		/*
306 		 * relocating:
307 		 *	call	elf_plt_trace
308 		 */
309 		symvalue = (Xword)((uintptr_t)&elf_plt_trace -
310 		    (dyn_plt + 0x28));
311 		if (do_reloc(R_SPARC_WDISP30, (uchar_t *)(dyn_plt + 0x28),
312 		    &symvalue, MSG_ORIG(MSG_SYM_ELFPLTTRACE),
313 		    MSG_ORIG(MSG_SPECFIL_DYNPLT), lml) == 0) {
314 			*fail = 1;
315 			return (0);
316 		}
317 
318 		*dyndata++ = (uintptr_t)rlmp;
319 		*dyndata++ = (uintptr_t)dlmp;
320 		*(ulong_t *)dyndata++ = symndx;
321 		*(ulong_t *)dyndata++ = sb_flags;
322 		symp = (Sym *)dyndata;
323 		*symp = *sym;
324 		symp->st_name += (Word)STRTAB(dlmp);
325 		symp->st_value = (Addr)to;
326 
327 		iflush_range((void *)dyn_plt, sizeof (dyn_plt_template));
328 	}
329 
330 	(void) elf_plt_write((uintptr_t)addr, (uintptr_t)addr,
331 	    rptr, (uintptr_t)dyn_plt, 0);
332 	return ((caddr_t)dyn_plt);
333 }
334 
335 
336 /*
337  * Function binding routine - invoked on the first call to a function through
338  * the procedure linkage table;
339  * passes first through an assembly language interface.
340  *
341  * Takes the address of the PLT entry where the call originated,
342  * the offset into the relocation table of the associated
343  * relocation entry and the address of the link map (rt_private_map struct)
344  * for the entry.
345  *
346  * Returns the address of the function referenced after re-writing the PLT
347  * entry to invoke the function directly.
348  *
349  * On error, causes process to terminate with a signal.
350  */
351 ulong_t
352 elf_bndr(Rt_map *lmp, ulong_t pltoff, caddr_t from)
353 {
354 	Rt_map		*nlmp, *llmp;
355 	ulong_t		addr, vaddr, reloff, symval, rsymndx;
356 	char		*name;
357 	Rela		*rptr;
358 	Sym		*sym, *nsym;
359 	Xword		pltndx;
360 	uint_t		binfo, sb_flags = 0;
361 	Slookup		sl;
362 	Pltbindtype	pbtype;
363 	int		entry, lmflags;
364 	uint_t		dbg_class;
365 	Lm_list		*lml = LIST(lmp);
366 
367 	/*
368 	 * For compatibility with libthread (TI_VERSION 1) we track the entry
369 	 * value.  A zero value indicates we have recursed into ld.so.1 to
370 	 * further process a locking request.  Under this recursion we disable
371 	 * tsort and cleanup activities.
372 	 */
373 	entry = enter();
374 
375 	if ((lmflags = lml->lm_flags) & LML_FLG_RTLDLM) {
376 		dbg_class = dbg_desc->d_class;
377 		dbg_desc->d_class = 0;
378 	}
379 
380 	/*
381 	 * Must calculate true plt relocation address from reloc.
382 	 * Take offset, subtract number of reserved PLT entries, and divide
383 	 * by PLT entry size, which should give the index of the plt
384 	 * entry (and relocation entry since they have been defined to be
385 	 * in the same order).  Then we must multiply by the size of
386 	 * a relocation entry, which will give us the offset of the
387 	 * plt relocation entry from the start of them given by JMPREL(lm).
388 	 */
389 	addr = pltoff - M_PLT_RESERVSZ;
390 	pltndx = addr / M_PLT_ENTSIZE;
391 
392 	/*
393 	 * Perform some basic sanity checks.  If we didn't get a load map
394 	 * or the plt offset is invalid then its possible someone has walked
395 	 * over the plt entries or jumped to plt0 out of the blue.
396 	 */
397 	if (!lmp || ((addr % M_PLT_ENTSIZE) != 0)) {
398 		Conv_inv_buf_t	inv_buf;
399 
400 		eprintf(lml, ERR_FATAL, MSG_INTL(MSG_REL_PLTREF),
401 		    conv_reloc_SPARC_type(R_SPARC_JMP_SLOT, 0, &inv_buf),
402 		    EC_NATPTR(lmp), EC_XWORD(pltoff), EC_NATPTR(from));
403 		rtldexit(lml, 1);
404 	}
405 	reloff = pltndx * sizeof (Rela);
406 
407 	/*
408 	 * Use relocation entry to get symbol table entry and symbol name.
409 	 */
410 	addr = (ulong_t)JMPREL(lmp);
411 	rptr = (Rela *)(addr + reloff);
412 	rsymndx = ELF_R_SYM(rptr->r_info);
413 	sym = (Sym *)((ulong_t)SYMTAB(lmp) + (rsymndx * SYMENT(lmp)));
414 	name = (char *)(STRTAB(lmp) + sym->st_name);
415 
416 	/*
417 	 * Determine the last link-map of this list, this'll be the starting
418 	 * point for any tsort() processing.
419 	 */
420 	llmp = lml->lm_tail;
421 
422 	/*
423 	 * Find definition for symbol.
424 	 */
425 	sl.sl_name = name;
426 	sl.sl_cmap = lmp;
427 	sl.sl_imap = lml->lm_head;
428 	sl.sl_hash = 0;
429 	sl.sl_rsymndx = rsymndx;
430 	sl.sl_flags = LKUP_DEFT;
431 
432 	if ((nsym = lookup_sym(&sl, &nlmp, &binfo)) == 0) {
433 		eprintf(lml, ERR_FATAL, MSG_INTL(MSG_REL_NOSYM), NAME(lmp),
434 		    demangle(name));
435 		rtldexit(lml, 1);
436 	}
437 
438 	symval = nsym->st_value;
439 	if (!(FLAGS(nlmp) & FLG_RT_FIXED) &&
440 	    (nsym->st_shndx != SHN_ABS))
441 		symval += ADDR(nlmp);
442 	if ((lmp != nlmp) && ((FLAGS1(nlmp) & FL1_RT_NOINIFIN) == 0)) {
443 		/*
444 		 * Record that this new link map is now bound to the caller.
445 		 */
446 		if (bind_one(lmp, nlmp, BND_REFER) == 0)
447 			rtldexit(lml, 1);
448 	}
449 
450 	if ((lml->lm_tflags | FLAGS1(lmp)) & LML_TFLG_AUD_SYMBIND) {
451 		ulong_t	symndx = (((uintptr_t)nsym -
452 		    (uintptr_t)SYMTAB(nlmp)) / SYMENT(nlmp));
453 
454 		symval = audit_symbind(lmp, nlmp, nsym, symndx, symval,
455 		    &sb_flags);
456 	}
457 
458 	if (FLAGS(lmp) & FLG_RT_FIXED)
459 		vaddr = 0;
460 	else
461 		vaddr = ADDR(lmp);
462 
463 	pbtype = PLT_T_NONE;
464 	if (!(rtld_flags & RT_FL_NOBIND)) {
465 		if (((lml->lm_tflags | FLAGS1(lmp)) &
466 		    (LML_TFLG_AUD_PLTENTER | LML_TFLG_AUD_PLTEXIT)) &&
467 		    AUDINFO(lmp)->ai_dynplts) {
468 			int	fail = 0;
469 			ulong_t	symndx = (((uintptr_t)nsym -
470 			    (uintptr_t)SYMTAB(nlmp)) / SYMENT(nlmp));
471 
472 			symval = (ulong_t)elf_plt_trace_write((caddr_t)vaddr,
473 			    rptr, lmp, nlmp, nsym, symndx, pltndx,
474 			    (caddr_t)symval, sb_flags, &fail);
475 			if (fail)
476 				rtldexit(lml, 1);
477 		} else {
478 			/*
479 			 * Write standard PLT entry to jump directly
480 			 * to newly bound function.
481 			 */
482 			pbtype = elf_plt_write((uintptr_t)vaddr,
483 			    (uintptr_t)vaddr, rptr, symval, pltndx);
484 		}
485 	}
486 
487 	/*
488 	 * Print binding information and rebuild PLT entry.
489 	 */
490 	DBG_CALL(Dbg_bind_global(lmp, (Addr)from, (Off)(from - ADDR(lmp)),
491 	    pltndx, pbtype, nlmp, (Addr)symval, nsym->st_value, name, binfo));
492 
493 	/*
494 	 * Complete any processing for newly loaded objects.  Note we don't
495 	 * know exactly where any new objects are loaded (we know the object
496 	 * that supplied the symbol, but others may have been loaded lazily as
497 	 * we searched for the symbol), so sorting starts from the last
498 	 * link-map know on entry to this routine.
499 	 */
500 	if (entry)
501 		load_completion(llmp);
502 
503 	/*
504 	 * Some operations like dldump() or dlopen()'ing a relocatable object
505 	 * result in objects being loaded on rtld's link-map, make sure these
506 	 * objects are initialized also.
507 	 */
508 	if ((LIST(nlmp)->lm_flags & LML_FLG_RTLDLM) && LIST(nlmp)->lm_init)
509 		load_completion(nlmp);
510 
511 	/*
512 	 * If the object we've bound to is in the process of being initialized
513 	 * by another thread, determine whether we should block.
514 	 */
515 	is_dep_ready(nlmp, lmp, DBG_WAIT_SYMBOL);
516 
517 	/*
518 	 * Make sure the object to which we've bound has had it's .init fired.
519 	 * Cleanup before return to user code.
520 	 */
521 	if (entry) {
522 		is_dep_init(nlmp, lmp);
523 		leave(lml);
524 	}
525 
526 	if (lmflags & LML_FLG_RTLDLM)
527 		dbg_desc->d_class = dbg_class;
528 
529 	return (symval);
530 }
531 
532 
533 /*
534  * Read and process the relocations for one link object, we assume all
535  * relocation sections for loadable segments are stored contiguously in
536  * the file.
537  */
538 int
539 elf_reloc(Rt_map *lmp, uint_t plt)
540 {
541 	ulong_t		relbgn, relend, relsiz, basebgn, pltbgn, pltend;
542 	ulong_t		roffset, rsymndx, psymndx = 0, etext = ETEXT(lmp);
543 	ulong_t		emap, dsymndx, pltndx;
544 	uchar_t		rtype;
545 	long		reladd, value, pvalue;
546 	Sym		*symref, *psymref, *symdef, *psymdef;
547 	char		*name, *pname;
548 	Rt_map		*_lmp, *plmp;
549 	int		textrel = 0, ret = 1, noplt = 0;
550 	long		relacount = RELACOUNT(lmp);
551 	Rela		*rel;
552 	Pltbindtype	pbtype;
553 	uint_t		binfo, pbinfo;
554 	Alist		*bound = 0;
555 
556 	/*
557 	 * If an object has any DT_REGISTER entries associated with
558 	 * it, they are processed now.
559 	 */
560 	if ((plt == 0) && (FLAGS(lmp) & FLG_RT_REGSYMS)) {
561 		if (elf_regsyms(lmp) == 0)
562 			return (0);
563 	}
564 
565 	/*
566 	 * Although only necessary for lazy binding, initialize the first
567 	 * procedure linkage table entry to go to elf_rtbndr().  dbx(1) seems
568 	 * to find this useful.
569 	 */
570 	if ((plt == 0) && PLTGOT(lmp)) {
571 		if ((ulong_t)PLTGOT(lmp) < etext) {
572 			if (elf_set_prot(lmp, PROT_WRITE) == 0)
573 				return (0);
574 			textrel = 1;
575 		}
576 		elf_plt_init(PLTGOT(lmp), (caddr_t)lmp);
577 	}
578 
579 	/*
580 	 * Initialize the plt start and end addresses.
581 	 */
582 	if ((pltbgn = (ulong_t)JMPREL(lmp)) != 0)
583 		pltend = pltbgn + (ulong_t)(PLTRELSZ(lmp));
584 
585 	/*
586 	 * If we've been called upon to promote an RTLD_LAZY object to an
587 	 * RTLD_NOW then we're only interested in scaning the .plt table.
588 	 */
589 	if (plt) {
590 		relbgn = pltbgn;
591 		relend = pltend;
592 	} else {
593 		/*
594 		 * The relocation sections appear to the run-time linker as a
595 		 * single table.  Determine the address of the beginning and end
596 		 * of this table.  There are two different interpretations of
597 		 * the ABI at this point:
598 		 *
599 		 *   o	The REL table and its associated RELSZ indicate the
600 		 *	concatenation of *all* relocation sections (this is the
601 		 *	model our link-editor constructs).
602 		 *
603 		 *   o	The REL table and its associated RELSZ indicate the
604 		 *	concatenation of all *but* the .plt relocations.  These
605 		 *	relocations are specified individually by the JMPREL and
606 		 *	PLTRELSZ entries.
607 		 *
608 		 * Determine from our knowledege of the relocation range and
609 		 * .plt range, the range of the total relocation table.  Note
610 		 * that one other ABI assumption seems to be that the .plt
611 		 * relocations always follow any other relocations, the
612 		 * following range checking drops that assumption.
613 		 */
614 		relbgn = (ulong_t)(REL(lmp));
615 		relend = relbgn + (ulong_t)(RELSZ(lmp));
616 		if (pltbgn) {
617 			if (!relbgn || (relbgn > pltbgn))
618 				relbgn = pltbgn;
619 			if (!relbgn || (relend < pltend))
620 				relend = pltend;
621 		}
622 	}
623 	if (!relbgn || (relbgn == relend)) {
624 		DBG_CALL(Dbg_reloc_run(lmp, 0, plt, DBG_REL_NONE));
625 		return (1);
626 	}
627 
628 	relsiz = (ulong_t)(RELENT(lmp));
629 	basebgn = ADDR(lmp);
630 	emap = ADDR(lmp) + MSIZE(lmp);
631 
632 	DBG_CALL(Dbg_reloc_run(lmp, M_REL_SHT_TYPE, plt, DBG_REL_START));
633 
634 	/*
635 	 * If we're processing in lazy mode there is no need to scan the
636 	 * .rela.plt table.
637 	 */
638 	if (pltbgn && ((MODE(lmp) & RTLD_NOW) == 0))
639 		noplt = 1;
640 
641 	/*
642 	 * Loop through relocations.
643 	 */
644 	while (relbgn < relend) {
645 		Addr		vaddr;
646 		uint_t		sb_flags = 0;
647 
648 		rtype = ELF_R_TYPE(((Rela *)relbgn)->r_info);
649 
650 		/*
651 		 * If this is a RELATIVE relocation in a shared object (the
652 		 * common case), and if we are not debugging, then jump into a
653 		 * tighter relocation loop (elf_reloc_relative).  Only make the
654 		 * jump if we've been given a hint on the number of relocations.
655 		 */
656 		if ((rtype == R_SPARC_RELATIVE) &&
657 		    ((FLAGS(lmp) & FLG_RT_FIXED) == 0) && (DBG_ENABLED == 0)) {
658 			/*
659 			 * It's possible that the relative relocation block
660 			 * has relocations against the text segment as well
661 			 * as the data segment.  Since our optimized relocation
662 			 * engine does not check which segment the relocation
663 			 * is against - just mprotect it now if it's been
664 			 * marked as containing TEXTREL's.
665 			 */
666 			if ((textrel == 0) && (FLAGS1(lmp) & FL1_RT_TEXTREL)) {
667 				if (elf_set_prot(lmp, PROT_WRITE) == 0) {
668 					ret = 0;
669 					break;
670 				}
671 				textrel = 1;
672 			}
673 			if (relacount) {
674 				relbgn = elf_reloc_relacount(relbgn, relacount,
675 				    relsiz, basebgn);
676 				relacount = 0;
677 			} else {
678 				relbgn = elf_reloc_relative(relbgn, relend,
679 				    relsiz, basebgn, etext, emap);
680 			}
681 			if (relbgn >= relend)
682 				break;
683 			rtype = ELF_R_TYPE(((Rela *)relbgn)->r_info);
684 		}
685 
686 		roffset = ((Rela *)relbgn)->r_offset;
687 
688 		reladd = (long)(((Rela *)relbgn)->r_addend);
689 		rsymndx = ELF_R_SYM(((Rela *)relbgn)->r_info);
690 
691 		rel = (Rela *)relbgn;
692 		relbgn += relsiz;
693 
694 		/*
695 		 * Optimizations.
696 		 */
697 		if (rtype == R_SPARC_NONE)
698 			continue;
699 		if (noplt && ((ulong_t)rel >= pltbgn) &&
700 		    ((ulong_t)rel < pltend)) {
701 			relbgn = pltend;
702 			continue;
703 		}
704 
705 		if (rtype != R_SPARC_REGISTER) {
706 			/*
707 			 * If this is a shared object, add the base address
708 			 * to offset.
709 			 */
710 			if (!(FLAGS(lmp) & FLG_RT_FIXED))
711 				roffset += basebgn;
712 
713 			/*
714 			 * If this relocation is not against part of the image
715 			 * mapped into memory we skip it.
716 			 */
717 			if ((roffset < ADDR(lmp)) || (roffset > (ADDR(lmp) +
718 			    MSIZE(lmp)))) {
719 				elf_reloc_bad(lmp, (void *)rel, rtype, roffset,
720 				    rsymndx);
721 				continue;
722 			}
723 		}
724 
725 		/*
726 		 * If we're promoting .plts try and determine if this one has
727 		 * already been written.  An uninitialized .plts' second
728 		 * instruction is a branch.  Note, elf_plt_write() optimizes
729 		 * .plt relocations, and it's possible that a relocated entry
730 		 * is a branch.  If this is the case, we can't tell the
731 		 * difference between an uninitialized .plt and a relocated,
732 		 * .plt that uses a branch.  In this case, we'll simply redo
733 		 * the relocation calculation, which is a bit sad.
734 		 */
735 		if (plt) {
736 			ulong_t	*_roffset = (ulong_t *)roffset;
737 
738 			_roffset++;
739 			if ((*_roffset & (~(S_MASK(22)))) != M_BA_A)
740 				continue;
741 		}
742 
743 		binfo = 0;
744 		pltndx = (ulong_t)-1;
745 		pbtype = PLT_T_NONE;
746 		/*
747 		 * If a symbol index is specified then get the symbol table
748 		 * entry, locate the symbol definition, and determine its
749 		 * address.
750 		 */
751 		if (rsymndx) {
752 			/*
753 			 * Get the local symbol table entry.
754 			 */
755 			symref = (Sym *)((ulong_t)SYMTAB(lmp) +
756 			    (rsymndx * SYMENT(lmp)));
757 
758 			/*
759 			 * If this is a local symbol, just use the base address.
760 			 * (we should have no local relocations in the
761 			 * executable).
762 			 */
763 			if (ELF_ST_BIND(symref->st_info) == STB_LOCAL) {
764 				value = basebgn;
765 				name = (char *)0;
766 
767 				/*
768 				 * Special case TLS relocations.
769 				 */
770 				if (rtype == R_SPARC_TLS_DTPMOD32) {
771 					/*
772 					 * Use the TLS modid.
773 					 */
774 					value = TLSMODID(lmp);
775 
776 				} else if (rtype == R_SPARC_TLS_TPOFF32) {
777 					if ((value = elf_static_tls(lmp, symref,
778 					    rel, rtype, 0, roffset, 0)) == 0) {
779 						ret = 0;
780 						break;
781 					}
782 				}
783 			} else {
784 				/*
785 				 * If the symbol index is equal to the previous
786 				 * symbol index relocation we processed then
787 				 * reuse the previous values. (Note that there
788 				 * have been cases where a relocation exists
789 				 * against a copy relocation symbol, our ld(1)
790 				 * should optimize this away, but make sure we
791 				 * don't use the same symbol information should
792 				 * this case exist).
793 				 */
794 				if ((rsymndx == psymndx) &&
795 				    (rtype != R_SPARC_COPY)) {
796 					/* LINTED */
797 					if (psymdef == 0) {
798 						DBG_CALL(Dbg_bind_weak(lmp,
799 						    (Addr)roffset, (Addr)
800 						    (roffset - basebgn), name));
801 						continue;
802 					}
803 					/* LINTED */
804 					value = pvalue;
805 					/* LINTED */
806 					name = pname;
807 					symdef = psymdef;
808 					/* LINTED */
809 					symref = psymref;
810 					/* LINTED */
811 					_lmp = plmp;
812 					/* LINTED */
813 					binfo = pbinfo;
814 
815 					if ((LIST(_lmp)->lm_tflags |
816 					    FLAGS1(_lmp)) &
817 					    LML_TFLG_AUD_SYMBIND) {
818 						value = audit_symbind(lmp, _lmp,
819 						    /* LINTED */
820 						    symdef, dsymndx, value,
821 						    &sb_flags);
822 					}
823 				} else {
824 					Slookup		sl;
825 					uchar_t		bind;
826 
827 					/*
828 					 * Lookup the symbol definition.
829 					 */
830 					name = (char *)(STRTAB(lmp) +
831 					    symref->st_name);
832 
833 					sl.sl_name = name;
834 					sl.sl_cmap = lmp;
835 					sl.sl_imap = 0;
836 					sl.sl_hash = 0;
837 					sl.sl_rsymndx = rsymndx;
838 
839 					if (rtype == R_SPARC_COPY)
840 						sl.sl_flags = LKUP_COPY;
841 					else
842 						sl.sl_flags = LKUP_DEFT;
843 
844 					sl.sl_flags |= LKUP_ALLCNTLIST;
845 
846 					if (rtype != R_SPARC_JMP_SLOT)
847 						sl.sl_flags |= LKUP_SPEC;
848 
849 					bind = ELF_ST_BIND(symref->st_info);
850 					if (bind == STB_WEAK)
851 						sl.sl_flags |= LKUP_WEAK;
852 
853 					symdef = lookup_sym(&sl, &_lmp, &binfo);
854 
855 					/*
856 					 * If the symbol is not found and the
857 					 * reference was not to a weak symbol,
858 					 * report an error.  Weak references
859 					 * may be unresolved.
860 					 */
861 					/* BEGIN CSTYLED */
862 					if (symdef == 0) {
863 					    Lm_list	*lml = LIST(lmp);
864 
865 					    if (bind != STB_WEAK) {
866 						if (lml->lm_flags &
867 						    LML_FLG_IGNRELERR) {
868 						    continue;
869 						} else if (lml->lm_flags &
870 						    LML_FLG_TRC_WARN) {
871 						    (void) printf(MSG_INTL(
872 							MSG_LDD_SYM_NFOUND),
873 							demangle(name),
874 							NAME(lmp));
875 						    continue;
876 						} else {
877 						    DBG_CALL(Dbg_reloc_in(lml,
878 							ELF_DBG_RTLD, M_MACH,
879 							M_REL_SHT_TYPE, rel,
880 							NULL, name));
881 						    eprintf(lml, ERR_FATAL,
882 							MSG_INTL(MSG_REL_NOSYM),
883 							NAME(lmp),
884 							demangle(name));
885 						    ret = 0;
886 						    break;
887 						}
888 					    } else {
889 						psymndx = rsymndx;
890 						psymdef = 0;
891 
892 						DBG_CALL(Dbg_bind_weak(lmp,
893 						    (Addr)roffset, (Addr)
894 						    (roffset - basebgn), name));
895 						continue;
896 					    }
897 					}
898 					/* END CSTYLED */
899 
900 					/*
901 					 * If symbol was found in an object
902 					 * other than the referencing object
903 					 * then record the binding.
904 					 */
905 					if ((lmp != _lmp) && ((FLAGS1(_lmp) &
906 					    FL1_RT_NOINIFIN) == 0)) {
907 						if (alist_test(&bound, _lmp,
908 						    sizeof (Rt_map *),
909 						    AL_CNT_RELBIND) == 0) {
910 							ret = 0;
911 							break;
912 						}
913 					}
914 
915 					/*
916 					 * Calculate the location of definition;
917 					 * symbol value plus base address of
918 					 * containing shared object.
919 					 */
920 					if (IS_SIZE(rtype))
921 						value = symdef->st_size;
922 					else
923 						value = symdef->st_value;
924 
925 					if (!(FLAGS(_lmp) & FLG_RT_FIXED) &&
926 					    !(IS_SIZE(rtype)) &&
927 					    (symdef->st_shndx != SHN_ABS) &&
928 					    (ELF_ST_TYPE(symdef->st_info) !=
929 					    STT_TLS))
930 						value += ADDR(_lmp);
931 
932 					/*
933 					 * Retain this symbol index and the
934 					 * value in case it can be used for the
935 					 * subsequent relocations.
936 					 */
937 					if (rtype != R_SPARC_COPY) {
938 						psymndx = rsymndx;
939 						pvalue = value;
940 						pname = name;
941 						psymdef = symdef;
942 						psymref = symref;
943 						plmp = _lmp;
944 						pbinfo = binfo;
945 					}
946 					if ((LIST(_lmp)->lm_tflags |
947 					    FLAGS1(_lmp)) &
948 					    LML_TFLG_AUD_SYMBIND) {
949 						dsymndx = (((uintptr_t)symdef -
950 						    (uintptr_t)SYMTAB(_lmp)) /
951 						    SYMENT(_lmp));
952 						value = audit_symbind(lmp, _lmp,
953 						    symdef, dsymndx, value,
954 						    &sb_flags);
955 					}
956 				}
957 
958 				/*
959 				 * If relocation is PC-relative, subtract
960 				 * offset address.
961 				 */
962 				if (IS_PC_RELATIVE(rtype))
963 					value -= roffset;
964 
965 				/*
966 				 * Special case TLS relocations.
967 				 */
968 				if (rtype == R_SPARC_TLS_DTPMOD32) {
969 					/*
970 					 * Relocation value is the TLS modid.
971 					 */
972 					value = TLSMODID(_lmp);
973 
974 				} else if (rtype == R_SPARC_TLS_TPOFF32) {
975 					if ((value = elf_static_tls(_lmp,
976 					    symdef, rel, rtype, name, roffset,
977 					    value)) == 0) {
978 						ret = 0;
979 						break;
980 					}
981 				}
982 			}
983 		} else {
984 			/*
985 			 * Special cases.
986 			 */
987 			if (rtype == R_SPARC_REGISTER) {
988 				/*
989 				 * A register symbol associated with symbol
990 				 * index 0 is initialized (i.e. relocated) to
991 				 * a constant in the r_addend field rather than
992 				 * to a symbol value.
993 				 */
994 				value = 0;
995 
996 			} else if (rtype == R_SPARC_TLS_DTPMOD32) {
997 				/*
998 				 * TLS relocation value is the TLS modid.
999 				 */
1000 				value = TLSMODID(lmp);
1001 			} else
1002 				value = basebgn;
1003 			name = (char *)0;
1004 		}
1005 
1006 		DBG_CALL(Dbg_reloc_in(LIST(lmp), ELF_DBG_RTLD, M_MACH,
1007 		    M_REL_SHT_TYPE, rel, NULL, name));
1008 
1009 		/*
1010 		 * If this object has relocations in the text segment, turn
1011 		 * off the write protect.
1012 		 */
1013 		if ((rtype != R_SPARC_REGISTER) && (roffset < etext) &&
1014 		    (textrel == 0)) {
1015 			if (elf_set_prot(lmp, PROT_WRITE) == 0) {
1016 				ret = 0;
1017 				break;
1018 			}
1019 			textrel = 1;
1020 		}
1021 
1022 		/*
1023 		 * Call relocation routine to perform required relocation.
1024 		 */
1025 		switch (rtype) {
1026 		case R_SPARC_REGISTER:
1027 			/*
1028 			 * The v9 ABI 4.2.4 says that system objects may,
1029 			 * but are not required to, use register symbols
1030 			 * to inidcate how they use global registers. Thus
1031 			 * at least %g6, %g7 must be allowed in addition
1032 			 * to %g2 and %g3.
1033 			 */
1034 			value += reladd;
1035 			if (roffset == STO_SPARC_REGISTER_G1) {
1036 				set_sparc_g1(value);
1037 			} else if (roffset == STO_SPARC_REGISTER_G2) {
1038 				set_sparc_g2(value);
1039 			} else if (roffset == STO_SPARC_REGISTER_G3) {
1040 				set_sparc_g3(value);
1041 			} else if (roffset == STO_SPARC_REGISTER_G4) {
1042 				set_sparc_g4(value);
1043 			} else if (roffset == STO_SPARC_REGISTER_G5) {
1044 				set_sparc_g5(value);
1045 			} else if (roffset == STO_SPARC_REGISTER_G6) {
1046 				set_sparc_g6(value);
1047 			} else if (roffset == STO_SPARC_REGISTER_G7) {
1048 				set_sparc_g7(value);
1049 			} else {
1050 				eprintf(LIST(lmp), ERR_FATAL,
1051 				    MSG_INTL(MSG_REL_BADREG), NAME(lmp),
1052 				    EC_ADDR(roffset));
1053 				ret = 0;
1054 				break;
1055 			}
1056 
1057 			DBG_CALL(Dbg_reloc_apply_reg(LIST(lmp), ELF_DBG_RTLD,
1058 			    M_MACH, (Xword)roffset, (Xword)value));
1059 			break;
1060 		case R_SPARC_COPY:
1061 			if (elf_copy_reloc(name, symref, lmp, (void *)roffset,
1062 			    symdef, _lmp, (const void *)value) == 0)
1063 				ret = 0;
1064 			break;
1065 		case R_SPARC_JMP_SLOT:
1066 			pltndx = ((ulong_t)rel -
1067 			    (uintptr_t)JMPREL(lmp)) / relsiz;
1068 
1069 			if (FLAGS(lmp) & FLG_RT_FIXED)
1070 				vaddr = 0;
1071 			else
1072 				vaddr = ADDR(lmp);
1073 
1074 			if (((LIST(lmp)->lm_tflags | FLAGS1(lmp)) &
1075 			    (LML_TFLG_AUD_PLTENTER | LML_TFLG_AUD_PLTEXIT)) &&
1076 			    AUDINFO(lmp)->ai_dynplts) {
1077 				int	fail = 0;
1078 				ulong_t	symndx = (((uintptr_t)symdef -
1079 				    (uintptr_t)SYMTAB(_lmp)) / SYMENT(_lmp));
1080 
1081 				(void) elf_plt_trace_write((caddr_t)vaddr,
1082 				    (Rela *)rel, lmp, _lmp, symdef, symndx,
1083 				    pltndx, (caddr_t)value, sb_flags, &fail);
1084 				if (fail)
1085 					ret = 0;
1086 			} else {
1087 				/*
1088 				 * Write standard PLT entry to jump directly
1089 				 * to newly bound function.
1090 				 */
1091 				DBG_CALL(Dbg_reloc_apply_val(LIST(lmp),
1092 				    ELF_DBG_RTLD, (Xword)roffset,
1093 				    (Xword)value));
1094 				pbtype = elf_plt_write((uintptr_t)vaddr,
1095 				    (uintptr_t)vaddr, (void *)rel, value,
1096 				    pltndx);
1097 			}
1098 			break;
1099 		default:
1100 			value += reladd;
1101 
1102 			/*
1103 			 * Write the relocation out.  If this relocation is a
1104 			 * common basic write, skip the doreloc() engine.
1105 			 */
1106 			if ((rtype == R_SPARC_GLOB_DAT) ||
1107 			    (rtype == R_SPARC_32)) {
1108 				if (roffset & 0x3) {
1109 					Conv_inv_buf_t inv_buf;
1110 
1111 					eprintf(LIST(lmp), ERR_FATAL,
1112 					    MSG_INTL(MSG_REL_NONALIGN),
1113 					    conv_reloc_SPARC_type(rtype,
1114 					    0, &inv_buf),
1115 					    NAME(lmp), demangle(name),
1116 					    EC_OFF(roffset));
1117 					ret = 0;
1118 				} else
1119 					*(uint_t *)roffset += value;
1120 			} else {
1121 				if (do_reloc(rtype, (uchar_t *)roffset,
1122 				    (Xword *)&value, name,
1123 				    NAME(lmp), LIST(lmp)) == 0)
1124 					ret = 0;
1125 			}
1126 
1127 			/*
1128 			 * The value now contains the 'bit-shifted' value that
1129 			 * was or'ed into memory (this was set by do_reloc()).
1130 			 */
1131 			DBG_CALL(Dbg_reloc_apply_val(LIST(lmp), ELF_DBG_RTLD,
1132 			    (Xword)roffset, (Xword)value));
1133 
1134 			/*
1135 			 * If this relocation is against a text segment, make
1136 			 * sure that the instruction cache is flushed.
1137 			 */
1138 			if (textrel)
1139 				iflush_range((caddr_t)roffset, 0x4);
1140 		}
1141 
1142 		if ((ret == 0) &&
1143 		    ((LIST(lmp)->lm_flags & LML_FLG_TRC_WARN) == 0))
1144 			break;
1145 
1146 		if (binfo) {
1147 			DBG_CALL(Dbg_bind_global(lmp, (Addr)roffset,
1148 			    (Off)(roffset - basebgn), pltndx, pbtype,
1149 			    _lmp, (Addr)value, symdef->st_value, name, binfo));
1150 		}
1151 	}
1152 
1153 	return (relocate_finish(lmp, bound, textrel, ret));
1154 }
1155 
1156 /*
1157  * Provide a machine specific interface to the conversion routine.  By calling
1158  * the machine specific version, rather than the generic version, we insure that
1159  * the data tables/strings for all known machine versions aren't dragged into
1160  * ld.so.1.
1161  */
1162 const char *
1163 _conv_reloc_type(uint_t rel)
1164 {
1165 	static Conv_inv_buf_t	inv_buf;
1166 
1167 	return (conv_reloc_SPARC_type(rel, 0, &inv_buf));
1168 }
1169