xref: /illumos-gate/usr/src/cmd/sgs/rtld/sparc/sparc_elf.c (revision 4eaa471005973e11a6110b69fe990530b3b95a38)
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 /*
28  *	Copyright (c) 1988 AT&T
29  *	  All Rights Reserved
30  */
31 
32 /*
33  * SPARC machine dependent and ELF file class dependent functions.
34  * Contains routines for performing function binding and symbol relocations.
35  */
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	"_inline.h"
51 #include	"msg.h"
52 
53 extern void	iflush_range(caddr_t, size_t);
54 extern void	plt_full_range(uintptr_t, uintptr_t);
55 
56 int
57 elf_mach_flags_check(Rej_desc *rej, Ehdr *ehdr)
58 {
59 	/*
60 	 * Check machine type and flags.
61 	 */
62 	if (ehdr->e_machine != EM_SPARC) {
63 		if (ehdr->e_machine != EM_SPARC32PLUS) {
64 			rej->rej_type = SGS_REJ_MACH;
65 			rej->rej_info = (uint_t)ehdr->e_machine;
66 			return (0);
67 		}
68 		if ((ehdr->e_flags & EF_SPARC_32PLUS) == 0) {
69 			rej->rej_type = SGS_REJ_MISFLAG;
70 			rej->rej_info = (uint_t)ehdr->e_flags;
71 			return (0);
72 		}
73 		if ((ehdr->e_flags & ~at_flags) & EF_SPARC_32PLUS_MASK) {
74 			rej->rej_type = SGS_REJ_BADFLAG;
75 			rej->rej_info = (uint_t)ehdr->e_flags;
76 			return (0);
77 		}
78 	} else if ((ehdr->e_flags & ~EF_SPARCV9_MM) != 0) {
79 		rej->rej_type = SGS_REJ_BADFLAG;
80 		rej->rej_info = (uint_t)ehdr->e_flags;
81 		return (0);
82 	}
83 	return (1);
84 }
85 
86 void
87 ldso_plt_init(Rt_map *lmp)
88 {
89 	/*
90 	 * There is no need to analyze ld.so because we don't map in any of
91 	 * its dependencies.  However we may map these dependencies in later
92 	 * (as if ld.so had dlopened them), so initialize the plt and the
93 	 * permission information.
94 	 */
95 	if (PLTGOT(lmp))
96 		elf_plt_init((PLTGOT(lmp)), (caddr_t)lmp);
97 }
98 
99 /*
100  * elf_plt_write() will test to see how far away our destination
101  *	address lies.  If it is close enough that a branch can
102  *	be used instead of a jmpl - we will fill the plt in with
103  * 	single branch.  The branches are much quicker then
104  *	a jmpl instruction - see bug#4356879 for further
105  *	details.
106  *
107  *	NOTE: we pass in both a 'pltaddr' and a 'vpltaddr' since
108  *		librtld/dldump update PLT's who's physical
109  *		address is not the same as the 'virtual' runtime
110  *		address.
111  */
112 Pltbindtype
113 /* ARGSUSED4 */
114 elf_plt_write(uintptr_t addr, uintptr_t vaddr, void *rptr, uintptr_t symval,
115 	Xword pltndx)
116 {
117 	Rela		*rel = (Rela *)rptr;
118 	uintptr_t	vpltaddr, pltaddr;
119 	long		disp;
120 
121 	pltaddr = addr + rel->r_offset;
122 	vpltaddr = vaddr + rel->r_offset;
123 	disp = symval - vpltaddr - 4;
124 
125 	/*
126 	 * Test if the destination address is close enough to use
127 	 * a ba,a... instruction to reach it.
128 	 */
129 	if (S_INRANGE(disp, 23) && !(rtld_flags & RT_FL_NOBAPLT)) {
130 		uint_t		*pltent, bainstr;
131 		Pltbindtype	rc;
132 
133 		pltent = (uint_t *)pltaddr;
134 
135 		/*
136 		 * The
137 		 *
138 		 *	ba,a,pt %icc, <dest>
139 		 *
140 		 * is the most efficient of the PLT's.  If we
141 		 * are within +-20 bits *and* running on a
142 		 * v8plus architecture - use that branch.
143 		 */
144 		if ((at_flags & EF_SPARC_32PLUS) &&
145 		    S_INRANGE(disp, 20)) {
146 			bainstr = M_BA_A_PT;	/* ba,a,pt %icc,<dest> */
147 			bainstr |= (S_MASK(19) & (disp >> 2));
148 			rc = PLT_T_21D;
149 			DBG_CALL(pltcnt21d++);
150 		} else {
151 			/*
152 			 * Otherwise - we fall back to the good old
153 			 *
154 			 *	ba,a	<dest>
155 			 *
156 			 * Which still beats a jmpl instruction.
157 			 */
158 			bainstr = M_BA_A;		/* ba,a <dest> */
159 			bainstr |= (S_MASK(22) & (disp >> 2));
160 			rc = PLT_T_24D;
161 			DBG_CALL(pltcnt24d++);
162 		}
163 
164 		pltent[2] = M_NOP;		/* nop instr */
165 		pltent[1] = bainstr;
166 
167 		iflush_range((char *)(&pltent[1]), 4);
168 		pltent[0] = M_NOP;		/* nop instr */
169 		iflush_range((char *)(&pltent[0]), 4);
170 		return (rc);
171 	}
172 
173 	/*
174 	 * The PLT destination is not in reach of
175 	 * a branch instruction - so we fall back
176 	 * to a 'jmpl' sequence.
177 	 */
178 	plt_full_range(pltaddr, symval);
179 	DBG_CALL(pltcntfull++);
180 	return (PLT_T_FULL);
181 }
182 
183 /*
184  * Local storage space created on the stack created for this glue
185  * code includes space for:
186  *		0x4	pointer to dyn_data
187  *		0x4	size prev stack frame
188  */
189 static const uchar_t dyn_plt_template[] = {
190 /* 0x00 */	0x80, 0x90, 0x00, 0x1e,	/* tst   %fp */
191 /* 0x04 */	0x02, 0x80, 0x00, 0x04, /* be    0x14 */
192 /* 0x08 */	0x82, 0x27, 0x80, 0x0e,	/* sub   %sp, %fp, %g1 */
193 /* 0x0c */	0x10, 0x80, 0x00, 0x03, /* ba	 0x20 */
194 /* 0x10 */	0x01, 0x00, 0x00, 0x00, /* nop */
195 /* 0x14 */	0x82, 0x10, 0x20, 0x60, /* mov	0x60, %g1 */
196 /* 0x18 */	0x9d, 0xe3, 0xbf, 0x98,	/* save	%sp, -0x68, %sp */
197 /* 0x1c */	0xc2, 0x27, 0xbf, 0xf8,	/* st	%g1, [%fp + -0x8] */
198 /* 0x20 */	0x03, 0x00, 0x00, 0x00,	/* sethi %hi(val), %g1 */
199 /* 0x24 */	0x82, 0x10, 0x60, 0x00, /* or	 %g1, %lo(val), %g1 */
200 /* 0x28 */	0x40, 0x00, 0x00, 0x00,	/* call  <rel_addr> */
201 /* 0x2c */	0xc2, 0x27, 0xbf, 0xfc	/* st    %g1, [%fp + -0x4] */
202 };
203 
204 int	dyn_plt_ent_size = sizeof (dyn_plt_template) +
205 		sizeof (uintptr_t) +	/* reflmp */
206 		sizeof (uintptr_t) +	/* deflmp */
207 		sizeof (ulong_t) +	/* symndx */
208 		sizeof (ulong_t) +	/* sb_flags */
209 		sizeof (Sym);		/* symdef */
210 
211 /*
212  * the dynamic plt entry is:
213  *
214  *	tst	%fp
215  *	be	1f
216  *	nop
217  *	sub	%sp, %fp, %g1
218  *	ba	2f
219  *	nop
220  * 1:
221  *	mov	SA(MINFRAME), %g1	! if %fp is null this is the
222  *					!   'minimum stack'.  %fp is null
223  *					!   on the initial stack frame
224  * 2:
225  *	save	%sp, -(SA(MINFRAME) + 2 * CLONGSIZE), %sp
226  *	st	%g1, [%fp + -0x8] ! store prev_stack size in [%fp - 8]
227  *	sethi	%hi(dyn_data), %g1
228  *	or	%g1, %lo(dyn_data), %g1
229  *	call	elf_plt_trace
230  *	st	%g1, [%fp + -0x4] ! store dyn_data ptr in [%fp - 4]
231  * dyn data:
232  *	uintptr_t	reflmp
233  *	uintptr_t	deflmp
234  *	ulong_t		symndx
235  *	ulong_t		sb_flags
236  *	Sym		symdef
237  */
238 static caddr_t
239 elf_plt_trace_write(caddr_t addr, Rela *rptr, Rt_map *rlmp, Rt_map *dlmp,
240     Sym *sym, ulong_t symndx, ulong_t pltndx, caddr_t to, ulong_t sb_flags,
241     int *fail)
242 {
243 	extern ulong_t	elf_plt_trace();
244 	uchar_t		*dyn_plt;
245 	uintptr_t	*dyndata;
246 
247 	/*
248 	 * If both pltenter & pltexit have been disabled there
249 	 * there is no reason to even create the glue code.
250 	 */
251 	if ((sb_flags & (LA_SYMB_NOPLTENTER | LA_SYMB_NOPLTEXIT)) ==
252 	    (LA_SYMB_NOPLTENTER | LA_SYMB_NOPLTEXIT)) {
253 		(void) elf_plt_write((uintptr_t)addr, (uintptr_t)addr,
254 		    rptr, (uintptr_t)to, pltndx);
255 		return (to);
256 	}
257 
258 	/*
259 	 * We only need to add the glue code if there is an auditing
260 	 * library that is interested in this binding.
261 	 */
262 	dyn_plt = (uchar_t *)((uintptr_t)AUDINFO(rlmp)->ai_dynplts +
263 	    (pltndx * dyn_plt_ent_size));
264 
265 	/*
266 	 * Have we initialized this dynamic plt entry yet?  If we haven't do it
267 	 * now.  Otherwise this function has been called before, but from a
268 	 * different plt (ie. from another shared object).  In that case
269 	 * we just set the plt to point to the new dyn_plt.
270 	 */
271 	if (*dyn_plt == 0) {
272 		Sym	*symp;
273 		Xword	symvalue;
274 		Lm_list	*lml = LIST(rlmp);
275 
276 		(void) memcpy((void *)dyn_plt, dyn_plt_template,
277 		    sizeof (dyn_plt_template));
278 		dyndata = (uintptr_t *)((uintptr_t)dyn_plt +
279 		    sizeof (dyn_plt_template));
280 
281 		/*
282 		 * relocating:
283 		 *	sethi	%hi(dyndata), %g1
284 		 */
285 		symvalue = (Xword)dyndata;
286 		if (do_reloc_rtld(R_SPARC_HI22, (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_rtld(R_SPARC_LO10, (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 		    (uintptr_t)(dyn_plt + 0x28));
311 		if (do_reloc_rtld(R_SPARC_WDISP30, (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, rptr,
331 	    (uintptr_t)dyn_plt, 0);
332 	return ((caddr_t)dyn_plt);
333 }
334 
335 /*
336  * Function binding routine - invoked on the first call to a function through
337  * the procedure linkage table;
338  * passes first through an assembly language interface.
339  *
340  * Takes the address of the PLT entry where the call originated,
341  * the offset into the relocation table of the associated
342  * relocation entry and the address of the link map (rt_private_map struct)
343  * for the entry.
344  *
345  * Returns the address of the function referenced after re-writing the PLT
346  * entry to invoke the function directly.
347  *
348  * On error, causes process to terminate with a signal.
349  */
350 ulong_t
351 elf_bndr(Rt_map *lmp, ulong_t pltoff, caddr_t from)
352 {
353 	Rt_map		*nlmp, *llmp;
354 	ulong_t		addr, vaddr, reloff, symval, rsymndx;
355 	char		*name;
356 	Rela		*rptr;
357 	Sym		*rsym, *nsym;
358 	Xword		pltndx;
359 	uint_t		binfo, sb_flags = 0, dbg_class;
360 	Slookup		sl;
361 	Pltbindtype	pbtype;
362 	int		entry, lmflags;
363 	Lm_list		*lml;
364 
365 	/*
366 	 * For compatibility with libthread (TI_VERSION 1) we track the entry
367 	 * value.  A zero value indicates we have recursed into ld.so.1 to
368 	 * further process a locking request.  Under this recursion we disable
369 	 * tsort and cleanup activities.
370 	 */
371 	entry = enter(0);
372 
373 	lml = LIST(lmp);
374 	if ((lmflags = lml->lm_flags) & LML_FLG_RTLDLM) {
375 		dbg_class = dbg_desc->d_class;
376 		dbg_desc->d_class = 0;
377 	}
378 
379 	/*
380 	 * Must calculate true plt relocation address from reloc.
381 	 * Take offset, subtract number of reserved PLT entries, and divide
382 	 * by PLT entry size, which should give the index of the plt
383 	 * entry (and relocation entry since they have been defined to be
384 	 * in the same order).  Then we must multiply by the size of
385 	 * a relocation entry, which will give us the offset of the
386 	 * plt relocation entry from the start of them given by JMPREL(lm).
387 	 */
388 	addr = pltoff - M_PLT_RESERVSZ;
389 	pltndx = addr / M_PLT_ENTSIZE;
390 
391 	/*
392 	 * Perform some basic sanity checks.  If we didn't get a load map
393 	 * or the plt offset is invalid then its possible someone has walked
394 	 * over the plt entries or jumped to plt[0] out of the blue.
395 	 */
396 	if (!lmp || ((addr % M_PLT_ENTSIZE) != 0)) {
397 		Conv_inv_buf_t	inv_buf;
398 
399 		eprintf(lml, ERR_FATAL, MSG_INTL(MSG_REL_PLTREF),
400 		    conv_reloc_SPARC_type(R_SPARC_JMP_SLOT, 0, &inv_buf),
401 		    EC_NATPTR(lmp), EC_XWORD(pltoff), EC_NATPTR(from));
402 		rtldexit(lml, 1);
403 	}
404 	reloff = pltndx * sizeof (Rela);
405 
406 	/*
407 	 * Use relocation entry to get symbol table entry and symbol name.
408 	 */
409 	addr = (ulong_t)JMPREL(lmp);
410 	rptr = (Rela *)(addr + reloff);
411 	rsymndx = ELF_R_SYM(rptr->r_info);
412 	rsym = (Sym *)((ulong_t)SYMTAB(lmp) + (rsymndx * SYMENT(lmp)));
413 	name = (char *)(STRTAB(lmp) + rsym->st_name);
414 
415 	/*
416 	 * Determine the last link-map of this list, this'll be the starting
417 	 * point for any tsort() processing.
418 	 */
419 	llmp = lml->lm_tail;
420 
421 	/*
422 	 * Find definition for symbol.  Initialize the symbol lookup data
423 	 * structure.
424 	 */
425 	SLOOKUP_INIT(sl, name, lmp, lml->lm_head, ld_entry_cnt, 0,
426 	    rsymndx, rsym, 0, LKUP_DEFT);
427 
428 	if ((nsym = lookup_sym(&sl, &nlmp, &binfo, NULL)) == 0) {
429 		eprintf(lml, ERR_FATAL, MSG_INTL(MSG_REL_NOSYM), NAME(lmp),
430 		    demangle(name));
431 		rtldexit(lml, 1);
432 	}
433 
434 	symval = nsym->st_value;
435 	if (!(FLAGS(nlmp) & FLG_RT_FIXED) &&
436 	    (nsym->st_shndx != SHN_ABS))
437 		symval += ADDR(nlmp);
438 	if ((lmp != nlmp) && ((FLAGS1(nlmp) & FL1_RT_NOINIFIN) == 0)) {
439 		/*
440 		 * Record that this new link map is now bound to the caller.
441 		 */
442 		if (bind_one(lmp, nlmp, BND_REFER) == 0)
443 			rtldexit(lml, 1);
444 	}
445 
446 	if ((lml->lm_tflags | AFLAGS(lmp)) & LML_TFLG_AUD_SYMBIND) {
447 		ulong_t	symndx = (((uintptr_t)nsym -
448 		    (uintptr_t)SYMTAB(nlmp)) / SYMENT(nlmp));
449 
450 		symval = audit_symbind(lmp, nlmp, nsym, symndx, symval,
451 		    &sb_flags);
452 	}
453 
454 	if (FLAGS(lmp) & FLG_RT_FIXED)
455 		vaddr = 0;
456 	else
457 		vaddr = ADDR(lmp);
458 
459 	pbtype = PLT_T_NONE;
460 	if (!(rtld_flags & RT_FL_NOBIND)) {
461 		if (((lml->lm_tflags | AFLAGS(lmp)) &
462 		    (LML_TFLG_AUD_PLTENTER | LML_TFLG_AUD_PLTEXIT)) &&
463 		    AUDINFO(lmp)->ai_dynplts) {
464 			int	fail = 0;
465 			ulong_t	symndx = (((uintptr_t)nsym -
466 			    (uintptr_t)SYMTAB(nlmp)) / SYMENT(nlmp));
467 
468 			symval = (ulong_t)elf_plt_trace_write((caddr_t)vaddr,
469 			    rptr, lmp, nlmp, nsym, symndx, pltndx,
470 			    (caddr_t)symval, sb_flags, &fail);
471 			if (fail)
472 				rtldexit(lml, 1);
473 		} else {
474 			/*
475 			 * Write standard PLT entry to jump directly
476 			 * to newly bound function.
477 			 */
478 			pbtype = elf_plt_write((uintptr_t)vaddr,
479 			    (uintptr_t)vaddr, rptr, symval, pltndx);
480 		}
481 	}
482 
483 	/*
484 	 * Print binding information and rebuild PLT entry.
485 	 */
486 	DBG_CALL(Dbg_bind_global(lmp, (Addr)from, (Off)(from - ADDR(lmp)),
487 	    pltndx, pbtype, nlmp, (Addr)symval, nsym->st_value, name, binfo));
488 
489 	/*
490 	 * Complete any processing for newly loaded objects.  Note we don't
491 	 * know exactly where any new objects are loaded (we know the object
492 	 * that supplied the symbol, but others may have been loaded lazily as
493 	 * we searched for the symbol), so sorting starts from the last
494 	 * link-map know on entry to this routine.
495 	 */
496 	if (entry)
497 		load_completion(llmp);
498 
499 	/*
500 	 * Some operations like dldump() or dlopen()'ing a relocatable object
501 	 * result in objects being loaded on rtld's link-map, make sure these
502 	 * objects are initialized also.
503 	 */
504 	if ((LIST(nlmp)->lm_flags & LML_FLG_RTLDLM) && LIST(nlmp)->lm_init)
505 		load_completion(nlmp);
506 
507 	/*
508 	 * Make sure the object to which we've bound has had it's .init fired.
509 	 * Cleanup before return to user code.
510 	 */
511 	if (entry) {
512 		is_dep_init(nlmp, lmp);
513 		leave(lml, 0);
514 	}
515 
516 	if (lmflags & LML_FLG_RTLDLM)
517 		dbg_desc->d_class = dbg_class;
518 
519 	return (symval);
520 }
521 
522 /*
523  * Read and process the relocations for one link object, we assume all
524  * relocation sections for loadable segments are stored contiguously in
525  * the file.
526  */
527 int
528 elf_reloc(Rt_map *lmp, uint_t plt, int *in_nfavl, APlist **textrel)
529 {
530 	ulong_t		relbgn, relend, relsiz, basebgn, pltbgn, pltend;
531 	ulong_t		dsymndx, pltndx, roffset, rsymndx, psymndx = 0;
532 	uchar_t		rtype;
533 	long		reladd, value, pvalue, relacount = RELACOUNT(lmp);
534 	Sym		*symref, *psymref, *symdef, *psymdef;
535 	char		*name, *pname;
536 	Rt_map		*_lmp, *plmp;
537 	int		ret = 1, noplt = 0;
538 	Rela		*rel;
539 	Pltbindtype	pbtype;
540 	uint_t		binfo, pbinfo;
541 	APlist		*bound = NULL;
542 
543 	/*
544 	 * If an object has any DT_REGISTER entries associated with
545 	 * it, they are processed now.
546 	 */
547 	if ((plt == 0) && (FLAGS(lmp) & FLG_RT_REGSYMS)) {
548 		if (elf_regsyms(lmp) == 0)
549 			return (0);
550 	}
551 
552 	/*
553 	 * Although only necessary for lazy binding, initialize the first
554 	 * procedure linkage table entry to go to elf_rtbndr().  dbx(1) seems
555 	 * to find this useful.
556 	 */
557 	if ((plt == 0) && PLTGOT(lmp)) {
558 		mmapobj_result_t	*mpp;
559 
560 		/*
561 		 * Make sure the segment is writable.
562 		 */
563 		if ((((mpp =
564 		    find_segment((caddr_t)PLTGOT(lmp), lmp)) != NULL) &&
565 		    ((mpp->mr_prot & PROT_WRITE) == 0)) &&
566 		    ((set_prot(lmp, mpp, 1) == 0) ||
567 		    (aplist_append(textrel, mpp, AL_CNT_TEXTREL) == NULL)))
568 			return (0);
569 
570 		elf_plt_init(PLTGOT(lmp), (caddr_t)lmp);
571 	}
572 
573 	/*
574 	 * Initialize the plt start and end addresses.
575 	 */
576 	if ((pltbgn = (ulong_t)JMPREL(lmp)) != 0)
577 		pltend = pltbgn + (ulong_t)(PLTRELSZ(lmp));
578 
579 	/*
580 	 * If we've been called upon to promote an RTLD_LAZY object to an
581 	 * RTLD_NOW then we're only interested in scaning the .plt table.
582 	 */
583 	if (plt) {
584 		relbgn = pltbgn;
585 		relend = pltend;
586 	} else {
587 		/*
588 		 * The relocation sections appear to the run-time linker as a
589 		 * single table.  Determine the address of the beginning and end
590 		 * of this table.  There are two different interpretations of
591 		 * the ABI at this point:
592 		 *
593 		 *   o	The REL table and its associated RELSZ indicate the
594 		 *	concatenation of *all* relocation sections (this is the
595 		 *	model our link-editor constructs).
596 		 *
597 		 *   o	The REL table and its associated RELSZ indicate the
598 		 *	concatenation of all *but* the .plt relocations.  These
599 		 *	relocations are specified individually by the JMPREL and
600 		 *	PLTRELSZ entries.
601 		 *
602 		 * Determine from our knowledege of the relocation range and
603 		 * .plt range, the range of the total relocation table.  Note
604 		 * that one other ABI assumption seems to be that the .plt
605 		 * relocations always follow any other relocations, the
606 		 * following range checking drops that assumption.
607 		 */
608 		relbgn = (ulong_t)(REL(lmp));
609 		relend = relbgn + (ulong_t)(RELSZ(lmp));
610 		if (pltbgn) {
611 			if (!relbgn || (relbgn > pltbgn))
612 				relbgn = pltbgn;
613 			if (!relbgn || (relend < pltend))
614 				relend = pltend;
615 		}
616 	}
617 	if (!relbgn || (relbgn == relend)) {
618 		DBG_CALL(Dbg_reloc_run(lmp, 0, plt, DBG_REL_NONE));
619 		return (1);
620 	}
621 
622 	relsiz = (ulong_t)(RELENT(lmp));
623 	basebgn = ADDR(lmp);
624 
625 	DBG_CALL(Dbg_reloc_run(lmp, M_REL_SHT_TYPE, plt, DBG_REL_START));
626 
627 	/*
628 	 * If we're processing in lazy mode there is no need to scan the
629 	 * .rela.plt table.
630 	 */
631 	if (pltbgn && ((MODE(lmp) & RTLD_NOW) == 0))
632 		noplt = 1;
633 
634 	/*
635 	 * Loop through relocations.
636 	 */
637 	while (relbgn < relend) {
638 		mmapobj_result_t	*mpp;
639 		uint_t			sb_flags = 0;
640 		Addr			vaddr;
641 
642 		rtype = ELF_R_TYPE(((Rela *)relbgn)->r_info, M_MACH);
643 
644 		/*
645 		 * If this is a RELATIVE relocation in a shared object (the
646 		 * common case), and if we are not debugging, then jump into one
647 		 * of the tighter relocation loops.
648 		 */
649 		if ((rtype == R_SPARC_RELATIVE) &&
650 		    ((FLAGS(lmp) & FLG_RT_FIXED) == 0) && (DBG_ENABLED == 0)) {
651 			if (relacount) {
652 				relbgn = elf_reloc_relative_count(relbgn,
653 				    relacount, relsiz, basebgn, lmp, textrel);
654 				relacount = 0;
655 			} else {
656 				relbgn = elf_reloc_relative(relbgn, relend,
657 				    relsiz, basebgn, lmp, textrel);
658 			}
659 			if (relbgn >= relend)
660 				break;
661 			rtype = ELF_R_TYPE(((Rela *)relbgn)->r_info, M_MACH);
662 		}
663 
664 		roffset = ((Rela *)relbgn)->r_offset;
665 
666 		reladd = (long)(((Rela *)relbgn)->r_addend);
667 		rsymndx = ELF_R_SYM(((Rela *)relbgn)->r_info);
668 
669 		rel = (Rela *)relbgn;
670 		relbgn += relsiz;
671 
672 		/*
673 		 * Optimizations.
674 		 */
675 		if (rtype == R_SPARC_NONE)
676 			continue;
677 		if (noplt && ((ulong_t)rel >= pltbgn) &&
678 		    ((ulong_t)rel < pltend)) {
679 			relbgn = pltend;
680 			continue;
681 		}
682 
683 		if (rtype != R_SPARC_REGISTER) {
684 			/*
685 			 * If this is a shared object, add the base address
686 			 * to offset.
687 			 */
688 			if (!(FLAGS(lmp) & FLG_RT_FIXED))
689 				roffset += basebgn;
690 
691 			/*
692 			 * If this relocation is not against part of the image
693 			 * mapped into memory we skip it.
694 			 */
695 			if ((mpp = find_segment((caddr_t)roffset,
696 			    lmp)) == NULL) {
697 				elf_reloc_bad(lmp, (void *)rel, rtype, roffset,
698 				    rsymndx);
699 				continue;
700 			}
701 		}
702 
703 		/*
704 		 * If we're promoting .plts, try and determine if this one has
705 		 * already been written.  An uninitialized .plts' second
706 		 * instruction is a branch.  Note, elf_plt_write() optimizes
707 		 * .plt relocations, and it's possible that a relocated entry
708 		 * is a branch.  If this is the case, we can't tell the
709 		 * difference between an uninitialized .plt and a relocated,
710 		 * .plt that uses a branch.  In this case, we'll simply redo
711 		 * the relocation calculation, which is a bit sad.
712 		 */
713 		if (plt) {
714 			ulong_t	*_roffset = (ulong_t *)roffset;
715 
716 			_roffset++;
717 			if ((*_roffset & (~(S_MASK(22)))) != M_BA_A)
718 				continue;
719 		}
720 
721 		binfo = 0;
722 		pltndx = (ulong_t)-1;
723 		pbtype = PLT_T_NONE;
724 
725 		/*
726 		 * If a symbol index is specified then get the symbol table
727 		 * entry, locate the symbol definition, and determine its
728 		 * address.
729 		 */
730 		if (rsymndx) {
731 			/*
732 			 * Get the local symbol table entry.
733 			 */
734 			symref = (Sym *)((ulong_t)SYMTAB(lmp) +
735 			    (rsymndx * SYMENT(lmp)));
736 
737 			/*
738 			 * If this is a local symbol, just use the base address.
739 			 * (we should have no local relocations in the
740 			 * executable).
741 			 */
742 			if (ELF_ST_BIND(symref->st_info) == STB_LOCAL) {
743 				value = basebgn;
744 				name = (char *)0;
745 
746 				/*
747 				 * Special case TLS relocations.
748 				 */
749 				if (rtype == R_SPARC_TLS_DTPMOD32) {
750 					/*
751 					 * Use the TLS modid.
752 					 */
753 					value = TLSMODID(lmp);
754 
755 				} else if (rtype == R_SPARC_TLS_TPOFF32) {
756 					if ((value = elf_static_tls(lmp, symref,
757 					    rel, rtype, 0, roffset, 0)) == 0) {
758 						ret = 0;
759 						break;
760 					}
761 				}
762 			} else {
763 				/*
764 				 * If the symbol index is equal to the previous
765 				 * symbol index relocation we processed then
766 				 * reuse the previous values. (Note that there
767 				 * have been cases where a relocation exists
768 				 * against a copy relocation symbol, our ld(1)
769 				 * should optimize this away, but make sure we
770 				 * don't use the same symbol information should
771 				 * this case exist).
772 				 */
773 				if ((rsymndx == psymndx) &&
774 				    (rtype != R_SPARC_COPY)) {
775 					/* LINTED */
776 					if (psymdef == 0) {
777 						DBG_CALL(Dbg_bind_weak(lmp,
778 						    (Addr)roffset, (Addr)
779 						    (roffset - basebgn), name));
780 						continue;
781 					}
782 					/* LINTED */
783 					value = pvalue;
784 					/* LINTED */
785 					name = pname;
786 					symdef = psymdef;
787 					/* LINTED */
788 					symref = psymref;
789 					/* LINTED */
790 					_lmp = plmp;
791 					/* LINTED */
792 					binfo = pbinfo;
793 
794 					if ((LIST(_lmp)->lm_tflags |
795 					    AFLAGS(_lmp)) &
796 					    LML_TFLG_AUD_SYMBIND) {
797 						value = audit_symbind(lmp, _lmp,
798 						    /* LINTED */
799 						    symdef, dsymndx, value,
800 						    &sb_flags);
801 					}
802 				} else {
803 					Slookup		sl;
804 
805 					/*
806 					 * Lookup the symbol definition.
807 					 * Initialize the symbol lookup data
808 					 * structure.
809 					 */
810 					name = (char *)(STRTAB(lmp) +
811 					    symref->st_name);
812 
813 					SLOOKUP_INIT(sl, name, lmp, 0,
814 					    ld_entry_cnt, 0, rsymndx, symref,
815 					    rtype, LKUP_STDRELOC);
816 
817 					symdef = lookup_sym(&sl, &_lmp,
818 					    &binfo, in_nfavl);
819 
820 					/*
821 					 * If the symbol is not found and the
822 					 * reference was not to a weak symbol,
823 					 * report an error.  Weak references
824 					 * may be unresolved.
825 					 */
826 					/* BEGIN CSTYLED */
827 					if (symdef == 0) {
828 					    if (sl.sl_bind != STB_WEAK) {
829 						if (elf_reloc_error(lmp, name,
830 						    rel, binfo))
831 							continue;
832 
833 						ret = 0;
834 						break;
835 
836 					    } else {
837 						psymndx = rsymndx;
838 						psymdef = 0;
839 
840 						DBG_CALL(Dbg_bind_weak(lmp,
841 						    (Addr)roffset, (Addr)
842 						    (roffset - basebgn), name));
843 						continue;
844 					    }
845 					}
846 					/* END CSTYLED */
847 
848 					/*
849 					 * If symbol was found in an object
850 					 * other than the referencing object
851 					 * then record the binding.
852 					 */
853 					if ((lmp != _lmp) && ((FLAGS1(_lmp) &
854 					    FL1_RT_NOINIFIN) == 0)) {
855 						if (aplist_test(&bound, _lmp,
856 						    AL_CNT_RELBIND) == 0) {
857 							ret = 0;
858 							break;
859 						}
860 					}
861 
862 					/*
863 					 * Calculate the location of definition;
864 					 * symbol value plus base address of
865 					 * containing shared object.
866 					 */
867 					if (IS_SIZE(rtype))
868 						value = symdef->st_size;
869 					else
870 						value = symdef->st_value;
871 
872 					if (!(FLAGS(_lmp) & FLG_RT_FIXED) &&
873 					    !(IS_SIZE(rtype)) &&
874 					    (symdef->st_shndx != SHN_ABS) &&
875 					    (ELF_ST_TYPE(symdef->st_info) !=
876 					    STT_TLS))
877 						value += ADDR(_lmp);
878 
879 					/*
880 					 * Retain this symbol index and the
881 					 * value in case it can be used for the
882 					 * subsequent relocations.
883 					 */
884 					if (rtype != R_SPARC_COPY) {
885 						psymndx = rsymndx;
886 						pvalue = value;
887 						pname = name;
888 						psymdef = symdef;
889 						psymref = symref;
890 						plmp = _lmp;
891 						pbinfo = binfo;
892 					}
893 					if ((LIST(_lmp)->lm_tflags |
894 					    AFLAGS(_lmp)) &
895 					    LML_TFLG_AUD_SYMBIND) {
896 						dsymndx = (((uintptr_t)symdef -
897 						    (uintptr_t)SYMTAB(_lmp)) /
898 						    SYMENT(_lmp));
899 						value = audit_symbind(lmp, _lmp,
900 						    symdef, dsymndx, value,
901 						    &sb_flags);
902 					}
903 				}
904 
905 				/*
906 				 * If relocation is PC-relative, subtract
907 				 * offset address.
908 				 */
909 				if (IS_PC_RELATIVE(rtype))
910 					value -= roffset;
911 
912 				/*
913 				 * Special case TLS relocations.
914 				 */
915 				if (rtype == R_SPARC_TLS_DTPMOD32) {
916 					/*
917 					 * Relocation value is the TLS modid.
918 					 */
919 					value = TLSMODID(_lmp);
920 
921 				} else if (rtype == R_SPARC_TLS_TPOFF32) {
922 					if ((value = elf_static_tls(_lmp,
923 					    symdef, rel, rtype, name, roffset,
924 					    value)) == 0) {
925 						ret = 0;
926 						break;
927 					}
928 				}
929 			}
930 		} else {
931 			/*
932 			 * Special cases.
933 			 */
934 			if (rtype == R_SPARC_REGISTER) {
935 				/*
936 				 * A register symbol associated with symbol
937 				 * index 0 is initialized (i.e. relocated) to
938 				 * a constant in the r_addend field rather than
939 				 * to a symbol value.
940 				 */
941 				value = 0;
942 
943 			} else if (rtype == R_SPARC_TLS_DTPMOD32) {
944 				/*
945 				 * TLS relocation value is the TLS modid.
946 				 */
947 				value = TLSMODID(lmp);
948 			} else
949 				value = basebgn;
950 			name = (char *)0;
951 		}
952 
953 		DBG_CALL(Dbg_reloc_in(LIST(lmp), ELF_DBG_RTLD, M_MACH,
954 		    M_REL_SHT_TYPE, rel, NULL, 0, name));
955 
956 		/*
957 		 * Make sure the segment is writable.
958 		 */
959 		if ((rtype != R_SPARC_REGISTER) &&
960 		    ((mpp->mr_prot & PROT_WRITE) == 0) &&
961 		    ((set_prot(lmp, mpp, 1) == 0) ||
962 		    (aplist_append(textrel, mpp, AL_CNT_TEXTREL) == NULL))) {
963 			ret = 0;
964 			break;
965 		}
966 
967 		/*
968 		 * Call relocation routine to perform required relocation.
969 		 */
970 		switch (rtype) {
971 		case R_SPARC_REGISTER:
972 			/*
973 			 * The v9 ABI 4.2.4 says that system objects may,
974 			 * but are not required to, use register symbols
975 			 * to inidcate how they use global registers. Thus
976 			 * at least %g6, %g7 must be allowed in addition
977 			 * to %g2 and %g3.
978 			 */
979 			value += reladd;
980 			if (roffset == STO_SPARC_REGISTER_G1) {
981 				set_sparc_g1(value);
982 			} else if (roffset == STO_SPARC_REGISTER_G2) {
983 				set_sparc_g2(value);
984 			} else if (roffset == STO_SPARC_REGISTER_G3) {
985 				set_sparc_g3(value);
986 			} else if (roffset == STO_SPARC_REGISTER_G4) {
987 				set_sparc_g4(value);
988 			} else if (roffset == STO_SPARC_REGISTER_G5) {
989 				set_sparc_g5(value);
990 			} else if (roffset == STO_SPARC_REGISTER_G6) {
991 				set_sparc_g6(value);
992 			} else if (roffset == STO_SPARC_REGISTER_G7) {
993 				set_sparc_g7(value);
994 			} else {
995 				eprintf(LIST(lmp), ERR_FATAL,
996 				    MSG_INTL(MSG_REL_BADREG), NAME(lmp),
997 				    EC_ADDR(roffset));
998 				ret = 0;
999 				break;
1000 			}
1001 
1002 			DBG_CALL(Dbg_reloc_apply_reg(LIST(lmp), ELF_DBG_RTLD,
1003 			    M_MACH, (Xword)roffset, (Xword)value));
1004 			break;
1005 		case R_SPARC_COPY:
1006 			if (elf_copy_reloc(name, symref, lmp, (void *)roffset,
1007 			    symdef, _lmp, (const void *)value) == 0)
1008 				ret = 0;
1009 			break;
1010 		case R_SPARC_JMP_SLOT:
1011 			pltndx = ((ulong_t)rel -
1012 			    (uintptr_t)JMPREL(lmp)) / relsiz;
1013 
1014 			if (FLAGS(lmp) & FLG_RT_FIXED)
1015 				vaddr = 0;
1016 			else
1017 				vaddr = ADDR(lmp);
1018 
1019 			if (((LIST(lmp)->lm_tflags | AFLAGS(lmp)) &
1020 			    (LML_TFLG_AUD_PLTENTER | LML_TFLG_AUD_PLTEXIT)) &&
1021 			    AUDINFO(lmp)->ai_dynplts) {
1022 				int	fail = 0;
1023 				ulong_t	symndx = (((uintptr_t)symdef -
1024 				    (uintptr_t)SYMTAB(_lmp)) / SYMENT(_lmp));
1025 
1026 				(void) elf_plt_trace_write((caddr_t)vaddr,
1027 				    (Rela *)rel, lmp, _lmp, symdef, symndx,
1028 				    pltndx, (caddr_t)value, sb_flags, &fail);
1029 				if (fail)
1030 					ret = 0;
1031 			} else {
1032 				/*
1033 				 * Write standard PLT entry to jump directly
1034 				 * to newly bound function.
1035 				 */
1036 				DBG_CALL(Dbg_reloc_apply_val(LIST(lmp),
1037 				    ELF_DBG_RTLD, (Xword)roffset,
1038 				    (Xword)value));
1039 				pbtype = elf_plt_write((uintptr_t)vaddr,
1040 				    (uintptr_t)vaddr, (void *)rel, value,
1041 				    pltndx);
1042 			}
1043 			break;
1044 		default:
1045 			value += reladd;
1046 
1047 			/*
1048 			 * Write the relocation out.  If this relocation is a
1049 			 * common basic write, skip the doreloc() engine.
1050 			 */
1051 			if ((rtype == R_SPARC_GLOB_DAT) ||
1052 			    (rtype == R_SPARC_32)) {
1053 				if (roffset & 0x3) {
1054 					Conv_inv_buf_t inv_buf;
1055 
1056 					eprintf(LIST(lmp), ERR_FATAL,
1057 					    MSG_INTL(MSG_REL_NONALIGN),
1058 					    conv_reloc_SPARC_type(rtype,
1059 					    0, &inv_buf),
1060 					    NAME(lmp), demangle(name),
1061 					    EC_OFF(roffset));
1062 					ret = 0;
1063 				} else
1064 					*(uint_t *)roffset += value;
1065 			} else {
1066 				if (do_reloc_rtld(rtype, (uchar_t *)roffset,
1067 				    (Xword *)&value, name,
1068 				    NAME(lmp), LIST(lmp)) == 0)
1069 					ret = 0;
1070 			}
1071 
1072 			/*
1073 			 * The value now contains the 'bit-shifted' value that
1074 			 * was or'ed into memory (this was set by
1075 			 * do_reloc_rtld()).
1076 			 */
1077 			DBG_CALL(Dbg_reloc_apply_val(LIST(lmp), ELF_DBG_RTLD,
1078 			    (Xword)roffset, (Xword)value));
1079 
1080 			/*
1081 			 * If this relocation is against a text segment, make
1082 			 * sure that the instruction cache is flushed.
1083 			 */
1084 			if (textrel)
1085 				iflush_range((caddr_t)roffset, 0x4);
1086 		}
1087 
1088 		if ((ret == 0) &&
1089 		    ((LIST(lmp)->lm_flags & LML_FLG_TRC_WARN) == 0))
1090 			break;
1091 
1092 		if (binfo) {
1093 			DBG_CALL(Dbg_bind_global(lmp, (Addr)roffset,
1094 			    (Off)(roffset - basebgn), pltndx, pbtype,
1095 			    _lmp, (Addr)value, symdef->st_value, name, binfo));
1096 		}
1097 	}
1098 
1099 	return (relocate_finish(lmp, bound, ret));
1100 }
1101 
1102 /*
1103  * Provide a machine specific interface to the conversion routine.  By calling
1104  * the machine specific version, rather than the generic version, we insure that
1105  * the data tables/strings for all known machine versions aren't dragged into
1106  * ld.so.1.
1107  */
1108 const char *
1109 _conv_reloc_type(uint_t rel)
1110 {
1111 	static Conv_inv_buf_t	inv_buf;
1112 
1113 	return (conv_reloc_SPARC_type(rel, 0, &inv_buf));
1114 }
1115