?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
dmake: do not set MAKEFLAGS=k
[unleashed/tickless.git] / usr / src / cmd / sgs / libld / common / machrel.amd.c
blob4af77510c52e076e2bc88dda3f3674507bdb91fb
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) 2004, 2010, Oracle and/or its affiliates. All rights reserved.
24 */
25
26 /* Get the x86 version of the relocation engine */
27 #define DO_RELOC_LIBLD_X86
28
29 #include <string.h>
30 #include <stdio.h>
31 #include <strings.h>
32 #include <sys/elf_amd64.h>
33 #include <debug.h>
34 #include <krtld/reloc.h>
35 #include <i386/machdep_x86.h>
36 #include "msg.h"
37 #include "_libld.h"
38
39 /*
40 * This module uses do_reloc_ld() to execute several synthesized relocations.
41 * That function expects to be passed two things that we need to construct
42 * here:
43 *
44 * 1) A Rel_desc descriptor for each relocation type, from which the
45 * rel_rtype field, and nothing else, is obtained. This is easily
46 * handled by constructing the necessary descriptors.
47 *
48 * 2) A function, which called with the Rel_desc descriptor, returns
49 * a string representing the name of the symbol associated with
50 * the descriptor. The usual function for this is ld_reloc_sym_name().
51 * However, that function will not work in this case, as these synthetic
52 * relocations do not have an associated symbol. We supply the
53 * syn_rdesc_sym_name() function to simply return the fixed name.
54 */
55 static Rel_desc rdesc_r_amd64_gotpcrel = {
56 NULL, NULL, NULL, 0, 0, 0, R_AMD64_GOTPCREL };
57 static Rel_desc rdesc_r_amd64_32 = {
58 NULL, NULL, NULL, 0, 0, 0, R_AMD64_32 };
59 static Rel_desc rdesc_r_amd64_pc32 = {
60 NULL, NULL, NULL, 0, 0, 0, R_AMD64_PC32 };
61
62 /*ARGSUSED*/
63 static const char *
64 syn_rdesc_sym_name(Rel_desc *rdesc)
65 {
66 return (MSG_ORIG(MSG_SYM_PLTENT));
67 }
68
69 /*
70 * Search the GOT index list for a GOT entry with a matching reference and the
71 * proper addend.
72 */
73 static Gotndx *
74 ld_find_got_ndx(Alist *alp, Gotref gref, Ofl_desc *ofl, Rel_desc *rdesc)
75 {
76 Aliste idx;
77 Gotndx *gnp;
78
79 assert(rdesc != 0);
80
81 if ((gref == GOT_REF_TLSLD) && ofl->ofl_tlsldgotndx)
82 return (ofl->ofl_tlsldgotndx);
83
84 for (ALIST_TRAVERSE(alp, idx, gnp)) {
85 if ((rdesc->rel_raddend == gnp->gn_addend) &&
86 (gnp->gn_gotref == gref)) {
87 return (gnp);
88 }
89 }
90 return (NULL);
91 }
92
93 static Xword
94 ld_calc_got_offset(Rel_desc *rdesc, Ofl_desc *ofl)
95 {
96 Os_desc *osp = ofl->ofl_osgot;
97 Sym_desc *sdp = rdesc->rel_sym;
98 Xword gotndx;
99 Gotref gref;
100 Gotndx *gnp;
101
102 if (rdesc->rel_flags & FLG_REL_DTLS)
103 gref = GOT_REF_TLSGD;
104 else if (rdesc->rel_flags & FLG_REL_MTLS)
105 gref = GOT_REF_TLSLD;
106 else if (rdesc->rel_flags & FLG_REL_STLS)
107 gref = GOT_REF_TLSIE;
108 else
109 gref = GOT_REF_GENERIC;
110
111 gnp = ld_find_got_ndx(sdp->sd_GOTndxs, gref, ofl, rdesc);
112 assert(gnp);
113
114 gotndx = (Xword)gnp->gn_gotndx;
115
116 if ((rdesc->rel_flags & FLG_REL_DTLS) &&
117 (rdesc->rel_rtype == R_AMD64_DTPOFF64))
118 gotndx++;
119
120 return ((Xword)(osp->os_shdr->sh_addr + (gotndx * M_GOT_ENTSIZE)));
121 }
122
123 static Word
124 ld_init_rel(Rel_desc *reld, Word *typedata, void *reloc)
125 {
126 Rela *rel = (Rela *)reloc;
127
128 /* LINTED */
129 reld->rel_rtype = (Word)ELF_R_TYPE(rel->r_info, M_MACH);
130 reld->rel_roffset = rel->r_offset;
131 reld->rel_raddend = rel->r_addend;
132 *typedata = 0;
133
134 reld->rel_flags |= FLG_REL_RELA;
135
136 return ((Word)ELF_R_SYM(rel->r_info));
137 }
138
139 static void
140 ld_mach_eflags(Ehdr *ehdr, Ofl_desc *ofl)
141 {
142 ofl->ofl_dehdr->e_flags |= ehdr->e_flags;
143 }
144
145 static void
146 ld_mach_make_dynamic(Ofl_desc *ofl, size_t *cnt)
147 {
148 if (!(ofl->ofl_flags & FLG_OF_RELOBJ)) {
149 /*
150 * Create this entry if we are going to create a PLT table.
151 */
152 if (ofl->ofl_pltcnt)
153 (*cnt)++; /* DT_PLTGOT */
154 }
155 }
156
157 static void
158 ld_mach_update_odynamic(Ofl_desc *ofl, Dyn **dyn)
159 {
160 if (((ofl->ofl_flags & FLG_OF_RELOBJ) == 0) && ofl->ofl_pltcnt) {
161 (*dyn)->d_tag = DT_PLTGOT;
162 if (ofl->ofl_osgot)
163 (*dyn)->d_un.d_ptr = ofl->ofl_osgot->os_shdr->sh_addr;
164 else
165 (*dyn)->d_un.d_ptr = 0;
166 (*dyn)++;
167 }
168 }
169
170 static Xword
171 ld_calc_plt_addr(Sym_desc *sdp, Ofl_desc *ofl)
172 {
173 Xword value;
174
175 value = (Xword)(ofl->ofl_osplt->os_shdr->sh_addr) +
176 M_PLT_RESERVSZ + ((sdp->sd_aux->sa_PLTndx - 1) * M_PLT_ENTSIZE);
177 return (value);
178 }
179
180 /*
181 * Build a single plt entry - code is:
182 * JMP *name1@GOTPCREL(%rip)
183 * PUSHL $index
184 * JMP .PLT0
185 */
186 static uchar_t pltn_entry[M_PLT_ENTSIZE] = {
187 /* 0x00 jmpq *name1@GOTPCREL(%rip) */ 0xff, 0x25, 0x00, 0x00, 0x00, 0x00,
188 /* 0x06 pushq $index */ 0x68, 0x00, 0x00, 0x00, 0x00,
189 /* 0x0b jmpq .plt0(%rip) */ 0xe9, 0x00, 0x00, 0x00, 0x00
190 /* 0x10 */
191 };
192
193 static uintptr_t
194 plt_entry(Ofl_desc * ofl, Sym_desc * sdp)
195 {
196 uchar_t *plt0, *pltent, *gotent;
197 Sword plt_off;
198 Word got_off;
199 Xword val1;
200 int bswap = (ofl->ofl_flags1 & FLG_OF1_ENCDIFF) != 0;
201
202 got_off = sdp->sd_aux->sa_PLTGOTndx * M_GOT_ENTSIZE;
203 plt_off = M_PLT_RESERVSZ + ((sdp->sd_aux->sa_PLTndx - 1) *
204 M_PLT_ENTSIZE);
205 plt0 = (uchar_t *)(ofl->ofl_osplt->os_outdata->d_buf);
206 pltent = plt0 + plt_off;
207 gotent = (uchar_t *)(ofl->ofl_osgot->os_outdata->d_buf) + got_off;
208
209 bcopy(pltn_entry, pltent, sizeof (pltn_entry));
210 /*
211 * Fill in the got entry with the address of the next instruction.
212 */
213 /* LINTED */
214 *(Word *)gotent = ofl->ofl_osplt->os_shdr->sh_addr + plt_off +
215 M_PLT_INSSIZE;
216 if (bswap)
217 /* LINTED */
218 *(Word *)gotent = ld_bswap_Word(*(Word *)gotent);
219
220 /*
221 * If '-z noreloc' is specified - skip the do_reloc_ld
222 * stage.
223 */
224 if (!OFL_DO_RELOC(ofl))
225 return (1);
226
227 /*
228 * patchup:
229 * jmpq *name1@gotpcrel(%rip)
230 *
231 * NOTE: 0x06 represents next instruction.
232 */
233 val1 = (ofl->ofl_osgot->os_shdr->sh_addr + got_off) -
234 (ofl->ofl_osplt->os_shdr->sh_addr + plt_off) - 0x06;
235
236 if (do_reloc_ld(&rdesc_r_amd64_gotpcrel, &pltent[0x02], &val1,
237 syn_rdesc_sym_name, MSG_ORIG(MSG_SPECFIL_PLTENT), bswap,
238 ofl->ofl_lml) == 0) {
239 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_PLT_PLTNFAIL),
240 sdp->sd_aux->sa_PLTndx, demangle(sdp->sd_name));
241 return (S_ERROR);
242 }
243
244 /*
245 * patchup:
246 * pushq $pltndx
247 */
248 val1 = (Xword)(sdp->sd_aux->sa_PLTndx - 1);
249
250 if (do_reloc_ld(&rdesc_r_amd64_32, &pltent[0x07], &val1,
251 syn_rdesc_sym_name, MSG_ORIG(MSG_SPECFIL_PLTENT), bswap,
252 ofl->ofl_lml) == 0) {
253 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_PLT_PLTNFAIL),
254 sdp->sd_aux->sa_PLTndx, demangle(sdp->sd_name));
255 return (S_ERROR);
256 }
257
258 /*
259 * patchup:
260 * jmpq .plt0(%rip)
261 * NOTE: 0x10 represents next instruction. The rather complex
262 * series of casts is necessary to sign extend an offset into
263 * a 64-bit value while satisfying various compiler error
264 * checks. Handle with care.
265 */
266 val1 = (Xword)((intptr_t)((uintptr_t)plt0 -
267 (uintptr_t)(&pltent[0x10])));
268
269 if (do_reloc_ld(&rdesc_r_amd64_pc32, &pltent[0x0c], &val1,
270 syn_rdesc_sym_name, MSG_ORIG(MSG_SPECFIL_PLTENT), bswap,
271 ofl->ofl_lml) == 0) {
272 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_PLT_PLTNFAIL),
273 sdp->sd_aux->sa_PLTndx, demangle(sdp->sd_name));
274 return (S_ERROR);
275 }
276
277 return (1);
278 }
279
280 static uintptr_t
281 ld_perform_outreloc(Rel_desc * orsp, Ofl_desc * ofl, Boolean *remain_seen)
282 {
283 Os_desc * relosp, * osp = 0;
284 Word ndx;
285 Xword roffset, value;
286 Sxword raddend;
287 Rela rea;
288 char *relbits;
289 Sym_desc * sdp, * psym = (Sym_desc *)0;
290 int sectmoved = 0;
291
292 raddend = orsp->rel_raddend;
293 sdp = orsp->rel_sym;
294
295 /*
296 * If the section this relocation is against has been discarded
297 * (-zignore), then also discard (skip) the relocation itself.
298 */
299 if (orsp->rel_isdesc && ((orsp->rel_flags &
300 (FLG_REL_GOT | FLG_REL_BSS | FLG_REL_PLT | FLG_REL_NOINFO)) == 0) &&
301 (orsp->rel_isdesc->is_flags & FLG_IS_DISCARD)) {
302 DBG_CALL(Dbg_reloc_discard(ofl->ofl_lml, M_MACH, orsp));
303 return (1);
304 }
305
306 /*
307 * If this is a relocation against a move table, or expanded move
308 * table, adjust the relocation entries.
309 */
310 if (RELAUX_GET_MOVE(orsp))
311 ld_adj_movereloc(ofl, orsp);
312
313 /*
314 * If this is a relocation against a section then we need to adjust the
315 * raddend field to compensate for the new position of the input section
316 * within the new output section.
317 */
318 if (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION) {
319 if (ofl->ofl_parsyms &&
320 (sdp->sd_isc->is_flags & FLG_IS_RELUPD) &&
321 /* LINTED */
322 (psym = ld_am_I_partial(orsp, orsp->rel_raddend))) {
323 DBG_CALL(Dbg_move_outsctadj(ofl->ofl_lml, psym));
324 sectmoved = 1;
325 if (ofl->ofl_flags & FLG_OF_RELOBJ)
326 raddend = psym->sd_sym->st_value;
327 else
328 raddend = psym->sd_sym->st_value -
329 psym->sd_isc->is_osdesc->os_shdr->sh_addr;
330 /* LINTED */
331 raddend += (Off)_elf_getxoff(psym->sd_isc->is_indata);
332 if (psym->sd_isc->is_shdr->sh_flags & SHF_ALLOC)
333 raddend +=
334 psym->sd_isc->is_osdesc->os_shdr->sh_addr;
335 } else {
336 /* LINTED */
337 raddend += (Off)_elf_getxoff(sdp->sd_isc->is_indata);
338 if (sdp->sd_isc->is_shdr->sh_flags & SHF_ALLOC)
339 raddend +=
340 sdp->sd_isc->is_osdesc->os_shdr->sh_addr;
341 }
342 }
343
344 value = sdp->sd_sym->st_value;
345
346 if (orsp->rel_flags & FLG_REL_GOT) {
347 /*
348 * Note: for GOT relative relocations on amd64
349 * we discard the addend. It was relevant
350 * to the reference - not to the data item
351 * being referenced (ie: that -4 thing).
352 */
353 raddend = 0;
354 osp = ofl->ofl_osgot;
355 roffset = ld_calc_got_offset(orsp, ofl);
356
357 } else if (orsp->rel_flags & FLG_REL_PLT) {
358 /*
359 * Note that relocations for PLT's actually
360 * cause a relocation againt the GOT.
361 */
362 osp = ofl->ofl_osplt;
363 roffset = (ofl->ofl_osgot->os_shdr->sh_addr) +
364 sdp->sd_aux->sa_PLTGOTndx * M_GOT_ENTSIZE;
365 raddend = 0;
366 if (plt_entry(ofl, sdp) == S_ERROR)
367 return (S_ERROR);
368
369 } else if (orsp->rel_flags & FLG_REL_BSS) {
370 /*
371 * This must be a R_AMD64_COPY. For these set the roffset to
372 * point to the new symbols location.
373 */
374 osp = ofl->ofl_isbss->is_osdesc;
375 roffset = value;
376
377 /*
378 * The raddend doesn't mean anything in a R_SPARC_COPY
379 * relocation. Null it out because it can confuse people.
380 */
381 raddend = 0;
382 } else {
383 osp = RELAUX_GET_OSDESC(orsp);
384
385 /*
386 * Calculate virtual offset of reference point; equals offset
387 * into section + vaddr of section for loadable sections, or
388 * offset plus section displacement for nonloadable sections.
389 */
390 roffset = orsp->rel_roffset +
391 (Off)_elf_getxoff(orsp->rel_isdesc->is_indata);
392 if (!(ofl->ofl_flags & FLG_OF_RELOBJ))
393 roffset += orsp->rel_isdesc->is_osdesc->
394 os_shdr->sh_addr;
395 }
396
397 if ((osp == 0) || ((relosp = osp->os_relosdesc) == 0))
398 relosp = ofl->ofl_osrel;
399
400 /*
401 * Assign the symbols index for the output relocation. If the
402 * relocation refers to a SECTION symbol then it's index is based upon
403 * the output sections symbols index. Otherwise the index can be
404 * derived from the symbols index itself.
405 */
406 if (orsp->rel_rtype == R_AMD64_RELATIVE)
407 ndx = STN_UNDEF;
408 else if ((orsp->rel_flags & FLG_REL_SCNNDX) ||
409 (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION)) {
410 if (sectmoved == 0) {
411 /*
412 * Check for a null input section. This can
413 * occur if this relocation references a symbol
414 * generated by sym_add_sym().
415 */
416 if (sdp->sd_isc && sdp->sd_isc->is_osdesc)
417 ndx = sdp->sd_isc->is_osdesc->os_identndx;
418 else
419 ndx = sdp->sd_shndx;
420 } else
421 ndx = ofl->ofl_parexpnndx;
422 } else
423 ndx = sdp->sd_symndx;
424
425 /*
426 * Add the symbols 'value' to the addend field.
427 */
428 if (orsp->rel_flags & FLG_REL_ADVAL)
429 raddend += value;
430
431 /*
432 * The addend field for R_AMD64_DTPMOD64 means nothing. The addend
433 * is propagated in the corresponding R_AMD64_DTPOFF64 relocation.
434 */
435 if (orsp->rel_rtype == R_AMD64_DTPMOD64)
436 raddend = 0;
437
438 relbits = (char *)relosp->os_outdata->d_buf;
439
440 rea.r_info = ELF_R_INFO(ndx, orsp->rel_rtype);
441 rea.r_offset = roffset;
442 rea.r_addend = raddend;
443 DBG_CALL(Dbg_reloc_out(ofl, ELF_DBG_LD, SHT_RELA, &rea, relosp->os_name,
444 ld_reloc_sym_name(orsp)));
445
446 /*
447 * Assert we haven't walked off the end of our relocation table.
448 */
449 assert(relosp->os_szoutrels <= relosp->os_shdr->sh_size);
450
451 (void) memcpy((relbits + relosp->os_szoutrels),
452 (char *)&rea, sizeof (Rela));
453 relosp->os_szoutrels += (Xword)sizeof (Rela);
454
455 /*
456 * Determine if this relocation is against a non-writable, allocatable
457 * section. If so we may need to provide a text relocation diagnostic.
458 * Note that relocations against the .plt (R_AMD64_JUMP_SLOT) actually
459 * result in modifications to the .got.
460 */
461 if (orsp->rel_rtype == R_AMD64_JUMP_SLOT)
462 osp = ofl->ofl_osgot;
463
464 ld_reloc_remain_entry(orsp, osp, ofl, remain_seen);
465 return (1);
466 }
467
468 /*
469 * amd64 Instructions for TLS processing
470 */
471 static uchar_t tlsinstr_gd_ie[] = {
472 /*
473 * 0x00 movq %fs:0, %rax
474 */
475 0x64, 0x48, 0x8b, 0x04, 0x25,
476 0x00, 0x00, 0x00, 0x00,
477 /*
478 * 0x09 addq x@gottpoff(%rip), %rax
479 */
480 0x48, 0x03, 0x05, 0x00, 0x00,
481 0x00, 0x00
482 };
483
484 static uchar_t tlsinstr_gd_le[] = {
485 /*
486 * 0x00 movq %fs:0, %rax
487 */
488 0x64, 0x48, 0x8b, 0x04, 0x25,
489 0x00, 0x00, 0x00, 0x00,
490 /*
491 * 0x09 leaq x@gottpoff(%rip), %rax
492 */
493 0x48, 0x8d, 0x80, 0x00, 0x00,
494 0x00, 0x00
495 };
496
497 static uchar_t tlsinstr_ld_le[] = {
498 /*
499 * .byte 0x66
500 */
501 0x66,
502 /*
503 * .byte 0x66
504 */
505 0x66,
506 /*
507 * .byte 0x66
508 */
509 0x66,
510 /*
511 * movq %fs:0, %rax
512 */
513 0x64, 0x48, 0x8b, 0x04, 0x25,
514 0x00, 0x00, 0x00, 0x00
515 };
516
517 #define REX_B 0x1
518 #define REX_X 0x2
519 #define REX_R 0x4
520 #define REX_W 0x8
521 #define REX_PREFIX 0x40
522
523 #define REX_RW (REX_PREFIX | REX_R | REX_W)
524 #define REX_BW (REX_PREFIX | REX_B | REX_W)
525 #define REX_BRW (REX_PREFIX | REX_B | REX_R | REX_W)
526
527 #define REG_ESP 0x4
528
529 #define INSN_ADDMR 0x03 /* addq mem,reg */
530 #define INSN_ADDIR 0x81 /* addq imm,reg */
531 #define INSN_MOVMR 0x8b /* movq mem,reg */
532 #define INSN_MOVIR 0xc7 /* movq imm,reg */
533 #define INSN_LEA 0x8d /* leaq mem,reg */
534
535 static Fixupret
536 tls_fixups(Ofl_desc *ofl, Rel_desc *arsp)
537 {
538 Sym_desc *sdp = arsp->rel_sym;
539 Word rtype = arsp->rel_rtype;
540 uchar_t *offset;
541
542 offset = (uchar_t *)((uintptr_t)arsp->rel_roffset +
543 (uintptr_t)_elf_getxoff(arsp->rel_isdesc->is_indata) +
544 (uintptr_t)RELAUX_GET_OSDESC(arsp)->os_outdata->d_buf);
545
546 /*
547 * Note that in certain of the original insn sequences below, the
548 * instructions are not necessarily adjacent
549 */
550 if (sdp->sd_ref == REF_DYN_NEED) {
551 /*
552 * IE reference model
553 */
554 switch (rtype) {
555 case R_AMD64_TLSGD:
556 /*
557 * GD -> IE
558 *
559 * Transition:
560 * 0x00 .byte 0x66
561 * 0x01 leaq x@tlsgd(%rip), %rdi
562 * 0x08 .word 0x6666
563 * 0x0a rex64
564 * 0x0b call __tls_get_addr@plt
565 * 0x10
566 * To:
567 * 0x00 movq %fs:0, %rax
568 * 0x09 addq x@gottpoff(%rip), %rax
569 * 0x10
570 */
571 DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH,
572 R_AMD64_GOTTPOFF, arsp, ld_reloc_sym_name));
573 arsp->rel_rtype = R_AMD64_GOTTPOFF;
574 arsp->rel_roffset += 8;
575 arsp->rel_raddend = (Sxword)-4;
576
577 /*
578 * Adjust 'offset' to beginning of instruction
579 * sequence.
580 */
581 offset -= 4;
582 (void) memcpy(offset, tlsinstr_gd_ie,
583 sizeof (tlsinstr_gd_ie));
584 return (FIX_RELOC);
585
586 case R_AMD64_PLT32:
587 /*
588 * Fixup done via the TLS_GD relocation.
589 */
590 DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH,
591 R_AMD64_NONE, arsp, ld_reloc_sym_name));
592 return (FIX_DONE);
593 }
594 }
595
596 /*
597 * LE reference model
598 */
599 switch (rtype) {
600 case R_AMD64_TLSGD:
601 /*
602 * GD -> LE
603 *
604 * Transition:
605 * 0x00 .byte 0x66
606 * 0x01 leaq x@tlsgd(%rip), %rdi
607 * 0x08 .word 0x6666
608 * 0x0a rex64
609 * 0x0b call __tls_get_addr@plt
610 * 0x10
611 * To:
612 * 0x00 movq %fs:0, %rax
613 * 0x09 leaq x@tpoff(%rax), %rax
614 * 0x10
615 */
616 DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH,
617 R_AMD64_TPOFF32, arsp, ld_reloc_sym_name));
618 arsp->rel_rtype = R_AMD64_TPOFF32;
619 arsp->rel_roffset += 8;
620 arsp->rel_raddend = 0;
621
622 /*
623 * Adjust 'offset' to beginning of instruction sequence.
624 */
625 offset -= 4;
626 (void) memcpy(offset, tlsinstr_gd_le, sizeof (tlsinstr_gd_le));
627 return (FIX_RELOC);
628
629 case R_AMD64_GOTTPOFF: {
630 /*
631 * IE -> LE
632 *
633 * Transition 1:
634 * movq %fs:0, %reg
635 * addq x@gottpoff(%rip), %reg
636 * To:
637 * movq %fs:0, %reg
638 * leaq x@tpoff(%reg), %reg
639 *
640 * Transition (as a special case):
641 * movq %fs:0, %r12/%rsp
642 * addq x@gottpoff(%rip), %r12/%rsp
643 * To:
644 * movq %fs:0, %r12/%rsp
645 * addq x@tpoff(%rax), %r12/%rsp
646 *
647 * Transition 2:
648 * movq x@gottpoff(%rip), %reg
649 * movq %fs:(%reg), %reg
650 * To:
651 * movq x@tpoff(%reg), %reg
652 * movq %fs:(%reg), %reg
653 */
654 Conv_inv_buf_t inv_buf;
655 uint8_t reg; /* Register */
656
657 offset -= 3;
658
659 reg = offset[2] >> 3; /* Encoded dest. reg. operand */
660
661 DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH,
662 R_AMD64_TPOFF32, arsp, ld_reloc_sym_name));
663 arsp->rel_rtype = R_AMD64_TPOFF32;
664 arsp->rel_raddend = 0;
665
666 /*
667 * This is transition 2, and the special case of form 1 where
668 * a normal transition would index %rsp or %r12 and need a SIB
669 * byte in the leaq for which we lack space
670 */
671 if ((offset[1] == INSN_MOVMR) ||
672 ((offset[1] == INSN_ADDMR) && (reg == REG_ESP))) {
673 /*
674 * If we needed an extra bit of MOD.reg to refer to
675 * this register as the dest of the original movq we
676 * need an extra bit of MOD.rm to refer to it in the
677 * dest of the replacement movq or addq.
678 */
679 if (offset[0] == REX_RW)
680 offset[0] = REX_BW;
681
682 offset[1] = (offset[1] == INSN_MOVMR) ?
683 INSN_MOVIR : INSN_ADDIR;
684 offset[2] = 0xc0 | reg;
685
686 return (FIX_RELOC);
687 } else if (offset[1] == INSN_ADDMR) {
688 /*
689 * If we needed an extra bit of MOD.reg to refer to
690 * this register in the dest of the addq we need an
691 * extra bit of both MOD.reg and MOD.rm to refer to it
692 * in the source and dest of the leaq
693 */
694 if (offset[0] == REX_RW)
695 offset[0] = REX_BRW;
696
697 offset[1] = INSN_LEA;
698 offset[2] = 0x80 | (reg << 3) | reg;
699
700 return (FIX_RELOC);
701 }
702
703 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_REL_BADTLSINS),
704 conv_reloc_amd64_type(arsp->rel_rtype, 0, &inv_buf),
705 arsp->rel_isdesc->is_file->ifl_name,
706 ld_reloc_sym_name(arsp),
707 arsp->rel_isdesc->is_name,
708 EC_OFF(arsp->rel_roffset));
709 return (FIX_ERROR);
710 }
711 case R_AMD64_TLSLD:
712 /*
713 * LD -> LE
714 *
715 * Transition
716 * 0x00 leaq x1@tlsgd(%rip), %rdi
717 * 0x07 call __tls_get_addr@plt
718 * 0x0c
719 * To:
720 * 0x00 .byte 0x66
721 * 0x01 .byte 0x66
722 * 0x02 .byte 0x66
723 * 0x03 movq %fs:0, %rax
724 */
725 DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH,
726 R_AMD64_NONE, arsp, ld_reloc_sym_name));
727 offset -= 3;
728 (void) memcpy(offset, tlsinstr_ld_le, sizeof (tlsinstr_ld_le));
729 return (FIX_DONE);
730
731 case R_AMD64_DTPOFF32:
732 /*
733 * LD->LE
734 *
735 * Transition:
736 * 0x00 leaq x1@dtpoff(%rax), %rcx
737 * To:
738 * 0x00 leaq x1@tpoff(%rax), %rcx
739 */
740 DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH,
741 R_AMD64_TPOFF32, arsp, ld_reloc_sym_name));
742 arsp->rel_rtype = R_AMD64_TPOFF32;
743 arsp->rel_raddend = 0;
744 return (FIX_RELOC);
745 }
746
747 return (FIX_RELOC);
748 }
749
750 static uintptr_t
751 ld_do_activerelocs(Ofl_desc *ofl)
752 {
753 Rel_desc *arsp;
754 Rel_cachebuf *rcbp;
755 Aliste idx;
756 uintptr_t return_code = 1;
757 ofl_flag_t flags = ofl->ofl_flags;
758
759 if (aplist_nitems(ofl->ofl_actrels.rc_list) != 0)
760 DBG_CALL(Dbg_reloc_doact_title(ofl->ofl_lml));
761
762 /*
763 * Process active relocations.
764 */
765 REL_CACHE_TRAVERSE(&ofl->ofl_actrels, idx, rcbp, arsp) {
766 uchar_t *addr;
767 Xword value;
768 Sym_desc *sdp;
769 const char *ifl_name;
770 Xword refaddr;
771 int moved = 0;
772 Gotref gref;
773 Os_desc *osp;
774
775 /*
776 * If the section this relocation is against has been discarded
777 * (-zignore), then discard (skip) the relocation itself.
778 */
779 if ((arsp->rel_isdesc->is_flags & FLG_IS_DISCARD) &&
780 ((arsp->rel_flags & (FLG_REL_GOT | FLG_REL_BSS |
781 FLG_REL_PLT | FLG_REL_NOINFO)) == 0)) {
782 DBG_CALL(Dbg_reloc_discard(ofl->ofl_lml, M_MACH, arsp));
783 continue;
784 }
785
786 /*
787 * We determine what the 'got reference' model (if required)
788 * is at this point. This needs to be done before tls_fixup()
789 * since it may 'transition' our instructions.
790 *
791 * The got table entries have already been assigned,
792 * and we bind to those initial entries.
793 */
794 if (arsp->rel_flags & FLG_REL_DTLS)
795 gref = GOT_REF_TLSGD;
796 else if (arsp->rel_flags & FLG_REL_MTLS)
797 gref = GOT_REF_TLSLD;
798 else if (arsp->rel_flags & FLG_REL_STLS)
799 gref = GOT_REF_TLSIE;
800 else
801 gref = GOT_REF_GENERIC;
802
803 /*
804 * Perform any required TLS fixups.
805 */
806 if (arsp->rel_flags & FLG_REL_TLSFIX) {
807 Fixupret ret;
808
809 if ((ret = tls_fixups(ofl, arsp)) == FIX_ERROR)
810 return (S_ERROR);
811 if (ret == FIX_DONE)
812 continue;
813 }
814
815 /*
816 * If this is a relocation against a move table, or
817 * expanded move table, adjust the relocation entries.
818 */
819 if (RELAUX_GET_MOVE(arsp))
820 ld_adj_movereloc(ofl, arsp);
821
822 sdp = arsp->rel_sym;
823 refaddr = arsp->rel_roffset +
824 (Off)_elf_getxoff(arsp->rel_isdesc->is_indata);
825
826 if ((arsp->rel_flags & FLG_REL_CLVAL) ||
827 (arsp->rel_flags & FLG_REL_GOTCL))
828 value = 0;
829 else if (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION) {
830 Sym_desc *sym;
831
832 /*
833 * The value for a symbol pointing to a SECTION
834 * is based off of that sections position.
835 */
836 if ((sdp->sd_isc->is_flags & FLG_IS_RELUPD) &&
837 /* LINTED */
838 (sym = ld_am_I_partial(arsp, arsp->rel_raddend))) {
839 /*
840 * The symbol was moved, so adjust the value
841 * relative to the new section.
842 */
843 value = sym->sd_sym->st_value;
844 moved = 1;
845
846 /*
847 * The original raddend covers the displacement
848 * from the section start to the desired
849 * address. The value computed above gets us
850 * from the section start to the start of the
851 * symbol range. Adjust the old raddend to
852 * remove the offset from section start to
853 * symbol start, leaving the displacement
854 * within the range of the symbol.
855 */
856 arsp->rel_raddend -= sym->sd_osym->st_value;
857 } else {
858 value = _elf_getxoff(sdp->sd_isc->is_indata);
859 if (sdp->sd_isc->is_shdr->sh_flags & SHF_ALLOC)
860 value += sdp->sd_isc->is_osdesc->
861 os_shdr->sh_addr;
862 }
863 if (sdp->sd_isc->is_shdr->sh_flags & SHF_TLS)
864 value -= ofl->ofl_tlsphdr->p_vaddr;
865
866 } else if (IS_SIZE(arsp->rel_rtype)) {
867 /*
868 * Size relocations require the symbols size.
869 */
870 value = sdp->sd_sym->st_size;
871
872 } else if ((sdp->sd_flags & FLG_SY_CAP) &&
873 sdp->sd_aux && sdp->sd_aux->sa_PLTndx) {
874 /*
875 * If relocation is against a capabilities symbol, we
876 * need to jump to an associated PLT, so that at runtime
877 * ld.so.1 is involved to determine the best binding
878 * choice. Otherwise, the value is the symbols value.
879 */
880 value = ld_calc_plt_addr(sdp, ofl);
881 } else
882 value = sdp->sd_sym->st_value;
883
884 /*
885 * Relocation against the GLOBAL_OFFSET_TABLE.
886 */
887 if ((arsp->rel_flags & FLG_REL_GOT) &&
888 !ld_reloc_set_aux_osdesc(ofl, arsp, ofl->ofl_osgot))
889 return (S_ERROR);
890 osp = RELAUX_GET_OSDESC(arsp);
891
892 /*
893 * If loadable and not producing a relocatable object add the
894 * sections virtual address to the reference address.
895 */
896 if ((arsp->rel_flags & FLG_REL_LOAD) &&
897 ((flags & FLG_OF_RELOBJ) == 0))
898 refaddr += arsp->rel_isdesc->is_osdesc->
899 os_shdr->sh_addr;
900
901 /*
902 * If this entry has a PLT assigned to it, its value is actually
903 * the address of the PLT (and not the address of the function).
904 */
905 if (IS_PLT(arsp->rel_rtype)) {
906 if (sdp->sd_aux && sdp->sd_aux->sa_PLTndx)
907 value = ld_calc_plt_addr(sdp, ofl);
908 }
909
910 /*
911 * Add relocations addend to value. Add extra
912 * relocation addend if needed.
913 *
914 * Note: For GOT relative relocations on amd64 we discard the
915 * addend. It was relevant to the reference - not to the
916 * data item being referenced (ie: that -4 thing).
917 */
918 if ((arsp->rel_flags & FLG_REL_GOT) == 0)
919 value += arsp->rel_raddend;
920
921 /*
922 * Determine whether the value needs further adjustment. Filter
923 * through the attributes of the relocation to determine what
924 * adjustment is required. Note, many of the following cases
925 * are only applicable when a .got is present. As a .got is
926 * not generated when a relocatable object is being built,
927 * any adjustments that require a .got need to be skipped.
928 */
929 if ((arsp->rel_flags & FLG_REL_GOT) &&
930 ((flags & FLG_OF_RELOBJ) == 0)) {
931 Xword R1addr;
932 uintptr_t R2addr;
933 Word gotndx;
934 Gotndx *gnp;
935
936 /*
937 * Perform relocation against GOT table. Since this
938 * doesn't fit exactly into a relocation we place the
939 * appropriate byte in the GOT directly
940 *
941 * Calculate offset into GOT at which to apply
942 * the relocation.
943 */
944 gnp = ld_find_got_ndx(sdp->sd_GOTndxs, gref, ofl, arsp);
945 assert(gnp);
946
947 if (arsp->rel_rtype == R_AMD64_DTPOFF64)
948 gotndx = gnp->gn_gotndx + 1;
949 else
950 gotndx = gnp->gn_gotndx;
951
952 R1addr = (Xword)(gotndx * M_GOT_ENTSIZE);
953
954 /*
955 * Add the GOTs data's offset.
956 */
957 R2addr = R1addr + (uintptr_t)osp->os_outdata->d_buf;
958
959 DBG_CALL(Dbg_reloc_doact(ofl->ofl_lml, ELF_DBG_LD_ACT,
960 M_MACH, SHT_RELA, arsp, R1addr, value,
961 ld_reloc_sym_name));
962
963 /*
964 * And do it.
965 */
966 if (ofl->ofl_flags1 & FLG_OF1_ENCDIFF)
967 *(Xword *)R2addr = ld_bswap_Xword(value);
968 else
969 *(Xword *)R2addr = value;
970 continue;
971
972 } else if (IS_GOT_BASED(arsp->rel_rtype) &&
973 ((flags & FLG_OF_RELOBJ) == 0)) {
974 value -= ofl->ofl_osgot->os_shdr->sh_addr;
975
976 } else if (IS_GOTPCREL(arsp->rel_rtype) &&
977 ((flags & FLG_OF_RELOBJ) == 0)) {
978 Gotndx *gnp;
979
980 /*
981 * Calculation:
982 * G + GOT + A - P
983 */
984 gnp = ld_find_got_ndx(sdp->sd_GOTndxs, gref, ofl, arsp);
985 assert(gnp);
986 value = (Xword)(ofl->ofl_osgot->os_shdr-> sh_addr) +
987 ((Xword)gnp->gn_gotndx * M_GOT_ENTSIZE) +
988 arsp->rel_raddend - refaddr;
989
990 } else if (IS_GOT_PC(arsp->rel_rtype) &&
991 ((flags & FLG_OF_RELOBJ) == 0)) {
992 value = (Xword)(ofl->ofl_osgot->os_shdr->
993 sh_addr) - refaddr + arsp->rel_raddend;
994
995 } else if ((IS_PC_RELATIVE(arsp->rel_rtype)) &&
996 (((flags & FLG_OF_RELOBJ) == 0) ||
997 (osp == sdp->sd_isc->is_osdesc))) {
998 value -= refaddr;
999
1000 } else if (IS_TLS_INS(arsp->rel_rtype) &&
1001 IS_GOT_RELATIVE(arsp->rel_rtype) &&
1002 ((flags & FLG_OF_RELOBJ) == 0)) {
1003 Gotndx *gnp;
1004
1005 gnp = ld_find_got_ndx(sdp->sd_GOTndxs, gref, ofl, arsp);
1006 assert(gnp);
1007 value = (Xword)gnp->gn_gotndx * M_GOT_ENTSIZE;
1008
1009 } else if (IS_GOT_RELATIVE(arsp->rel_rtype) &&
1010 ((flags & FLG_OF_RELOBJ) == 0)) {
1011 Gotndx *gnp;
1012
1013 gnp = ld_find_got_ndx(sdp->sd_GOTndxs, gref, ofl, arsp);
1014 assert(gnp);
1015 value = (Xword)gnp->gn_gotndx * M_GOT_ENTSIZE;
1016
1017 } else if ((arsp->rel_flags & FLG_REL_STLS) &&
1018 ((flags & FLG_OF_RELOBJ) == 0)) {
1019 Xword tlsstatsize;
1020
1021 /*
1022 * This is the LE TLS reference model. Static
1023 * offset is hard-coded.
1024 */
1025 tlsstatsize = S_ROUND(ofl->ofl_tlsphdr->p_memsz,
1026 M_TLSSTATALIGN);
1027 value = tlsstatsize - value;
1028
1029 /*
1030 * Since this code is fixed up, it assumes a negative
1031 * offset that can be added to the thread pointer.
1032 */
1033 if (arsp->rel_rtype == R_AMD64_TPOFF32)
1034 value = -value;
1035 }
1036
1037 if (arsp->rel_isdesc->is_file)
1038 ifl_name = arsp->rel_isdesc->is_file->ifl_name;
1039 else
1040 ifl_name = MSG_INTL(MSG_STR_NULL);
1041
1042 /*
1043 * Make sure we have data to relocate. Compiler and assembler
1044 * developers have been known to generate relocations against
1045 * invalid sections (normally .bss), so for their benefit give
1046 * them sufficient information to help analyze the problem.
1047 * End users should never see this.
1048 */
1049 if (arsp->rel_isdesc->is_indata->d_buf == 0) {
1050 Conv_inv_buf_t inv_buf;
1051
1052 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_REL_EMPTYSEC),
1053 conv_reloc_amd64_type(arsp->rel_rtype, 0, &inv_buf),
1054 ifl_name, ld_reloc_sym_name(arsp),
1055 EC_WORD(arsp->rel_isdesc->is_scnndx),
1056 arsp->rel_isdesc->is_name);
1057 return (S_ERROR);
1058 }
1059
1060 /*
1061 * Get the address of the data item we need to modify.
1062 */
1063 addr = (uchar_t *)((uintptr_t)arsp->rel_roffset +
1064 (uintptr_t)_elf_getxoff(arsp->rel_isdesc->is_indata));
1065
1066 DBG_CALL(Dbg_reloc_doact(ofl->ofl_lml, ELF_DBG_LD_ACT,
1067 M_MACH, SHT_RELA, arsp, EC_NATPTR(addr), value,
1068 ld_reloc_sym_name));
1069 addr += (uintptr_t)osp->os_outdata->d_buf;
1070
1071 if ((((uintptr_t)addr - (uintptr_t)ofl->ofl_nehdr) >
1072 ofl->ofl_size) || (arsp->rel_roffset >
1073 osp->os_shdr->sh_size)) {
1074 int class;
1075 Conv_inv_buf_t inv_buf;
1076
1077 if (((uintptr_t)addr - (uintptr_t)ofl->ofl_nehdr) >
1078 ofl->ofl_size)
1079 class = ERR_FATAL;
1080 else
1081 class = ERR_WARNING;
1082
1083 ld_eprintf(ofl, class, MSG_INTL(MSG_REL_INVALOFFSET),
1084 conv_reloc_amd64_type(arsp->rel_rtype, 0, &inv_buf),
1085 ifl_name, EC_WORD(arsp->rel_isdesc->is_scnndx),
1086 arsp->rel_isdesc->is_name, ld_reloc_sym_name(arsp),
1087 EC_ADDR((uintptr_t)addr -
1088 (uintptr_t)ofl->ofl_nehdr));
1089
1090 if (class == ERR_FATAL) {
1091 return_code = S_ERROR;
1092 continue;
1093 }
1094 }
1095
1096 /*
1097 * The relocation is additive. Ignore the previous symbol
1098 * value if this local partial symbol is expanded.
1099 */
1100 if (moved)
1101 value -= *addr;
1102
1103 /*
1104 * If '-z noreloc' is specified - skip the do_reloc_ld stage.
1105 */
1106 if (OFL_DO_RELOC(ofl)) {
1107 /*
1108 * If this is a PROGBITS section and the running linker
1109 * has a different byte order than the target host,
1110 * tell do_reloc_ld() to swap bytes.
1111 */
1112 if (do_reloc_ld(arsp, addr, &value, ld_reloc_sym_name,
1113 ifl_name, OFL_SWAP_RELOC_DATA(ofl, arsp),
1114 ofl->ofl_lml) == 0) {
1115 ofl->ofl_flags |= FLG_OF_FATAL;
1116 return_code = S_ERROR;
1117 }
1118 }
1119 }
1120 return (return_code);
1121 }
1122
1123 static uintptr_t
1124 ld_add_outrel(Word flags, Rel_desc *rsp, Ofl_desc *ofl)
1125 {
1126 Rel_desc *orsp;
1127 Sym_desc *sdp = rsp->rel_sym;
1128
1129 /*
1130 * Static executables *do not* want any relocations against them.
1131 * Since our engine still creates relocations against a WEAK UNDEFINED
1132 * symbol in a static executable, it's best to disable them here
1133 * instead of through out the relocation code.
1134 */
1135 if (OFL_IS_STATIC_EXEC(ofl))
1136 return (1);
1137
1138 /*
1139 * If we are adding a output relocation against a section
1140 * symbol (non-RELATIVE) then mark that section. These sections
1141 * will be added to the .dynsym symbol table.
1142 */
1143 if (sdp && (rsp->rel_rtype != M_R_RELATIVE) &&
1144 ((flags & FLG_REL_SCNNDX) ||
1145 (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION))) {
1146
1147 /*
1148 * If this is a COMMON symbol - no output section
1149 * exists yet - (it's created as part of sym_validate()).
1150 * So - we mark here that when it's created it should
1151 * be tagged with the FLG_OS_OUTREL flag.
1152 */
1153 if ((sdp->sd_flags & FLG_SY_SPECSEC) &&
1154 (sdp->sd_sym->st_shndx == SHN_COMMON)) {
1155 if (ELF_ST_TYPE(sdp->sd_sym->st_info) != STT_TLS)
1156 ofl->ofl_flags1 |= FLG_OF1_BSSOREL;
1157 else
1158 ofl->ofl_flags1 |= FLG_OF1_TLSOREL;
1159 } else {
1160 Os_desc *osp;
1161 Is_desc *isp = sdp->sd_isc;
1162
1163 if (isp && ((osp = isp->is_osdesc) != NULL) &&
1164 ((osp->os_flags & FLG_OS_OUTREL) == 0)) {
1165 ofl->ofl_dynshdrcnt++;
1166 osp->os_flags |= FLG_OS_OUTREL;
1167 }
1168 }
1169 }
1170
1171 /* Enter it into the output relocation cache */
1172 if ((orsp = ld_reloc_enter(ofl, &ofl->ofl_outrels, rsp, flags)) == NULL)
1173 return (S_ERROR);
1174
1175 if (flags & FLG_REL_GOT)
1176 ofl->ofl_relocgotsz += (Xword)sizeof (Rela);
1177 else if (flags & FLG_REL_PLT)
1178 ofl->ofl_relocpltsz += (Xword)sizeof (Rela);
1179 else if (flags & FLG_REL_BSS)
1180 ofl->ofl_relocbsssz += (Xword)sizeof (Rela);
1181 else if (flags & FLG_REL_NOINFO)
1182 ofl->ofl_relocrelsz += (Xword)sizeof (Rela);
1183 else
1184 RELAUX_GET_OSDESC(orsp)->os_szoutrels += (Xword)sizeof (Rela);
1185
1186 if (orsp->rel_rtype == M_R_RELATIVE)
1187 ofl->ofl_relocrelcnt++;
1188
1189 /*
1190 * We don't perform sorting on PLT relocations because
1191 * they have already been assigned a PLT index and if we
1192 * were to sort them we would have to re-assign the plt indexes.
1193 */
1194 if (!(flags & FLG_REL_PLT))
1195 ofl->ofl_reloccnt++;
1196
1197 /*
1198 * Insure a GLOBAL_OFFSET_TABLE is generated if required.
1199 */
1200 if (IS_GOT_REQUIRED(orsp->rel_rtype))
1201 ofl->ofl_flags |= FLG_OF_BLDGOT;
1202
1203 /*
1204 * Identify and possibly warn of a displacement relocation.
1205 */
1206 if (orsp->rel_flags & FLG_REL_DISP) {
1207 ofl->ofl_dtflags_1 |= DF_1_DISPRELPND;
1208
1209 if (ofl->ofl_flags & FLG_OF_VERBOSE)
1210 ld_disp_errmsg(MSG_INTL(MSG_REL_DISPREL4), orsp, ofl);
1211 }
1212 DBG_CALL(Dbg_reloc_ors_entry(ofl->ofl_lml, ELF_DBG_LD, SHT_RELA,
1213 M_MACH, orsp));
1214 return (1);
1215 }
1216
1217 /*
1218 * process relocation for a LOCAL symbol
1219 */
1220 static uintptr_t
1221 ld_reloc_local(Rel_desc * rsp, Ofl_desc * ofl)
1222 {
1223 ofl_flag_t flags = ofl->ofl_flags;
1224 Sym_desc *sdp = rsp->rel_sym;
1225 Word shndx = sdp->sd_sym->st_shndx;
1226 Word ortype = rsp->rel_rtype;
1227
1228 /*
1229 * if ((shared object) and (not pc relative relocation) and
1230 * (not against ABS symbol))
1231 * then
1232 * build R_AMD64_RELATIVE
1233 * fi
1234 */
1235 if ((flags & (FLG_OF_SHAROBJ | FLG_OF_PIE)) &&
1236 (rsp->rel_flags & FLG_REL_LOAD) &&
1237 !(IS_PC_RELATIVE(rsp->rel_rtype)) && !(IS_SIZE(rsp->rel_rtype)) &&
1238 !(IS_GOT_BASED(rsp->rel_rtype)) &&
1239 !(rsp->rel_isdesc != NULL &&
1240 (rsp->rel_isdesc->is_shdr->sh_type == SHT_SUNW_dof)) &&
1241 (((sdp->sd_flags & FLG_SY_SPECSEC) == 0) ||
1242 (shndx != SHN_ABS) || (sdp->sd_aux && sdp->sd_aux->sa_symspec))) {
1243
1244 /*
1245 * R_AMD64_RELATIVE updates a 64bit address, if this
1246 * relocation isn't a 64bit binding then we can not
1247 * simplify it to a RELATIVE relocation.
1248 */
1249 if (reloc_table[ortype].re_fsize != sizeof (Addr)) {
1250 return (ld_add_outrel(0, rsp, ofl));
1251 }
1252
1253 rsp->rel_rtype = R_AMD64_RELATIVE;
1254 if (ld_add_outrel(FLG_REL_ADVAL, rsp, ofl) == S_ERROR)
1255 return (S_ERROR);
1256 rsp->rel_rtype = ortype;
1257 return (1);
1258 }
1259
1260 /*
1261 * If the relocation is against a 'non-allocatable' section
1262 * and we can not resolve it now - then give a warning
1263 * message.
1264 *
1265 * We can not resolve the symbol if either:
1266 * a) it's undefined
1267 * b) it's defined in a shared library and a
1268 * COPY relocation hasn't moved it to the executable
1269 *
1270 * Note: because we process all of the relocations against the
1271 * text segment before any others - we know whether
1272 * or not a copy relocation will be generated before
1273 * we get here (see reloc_init()->reloc_segments()).
1274 */
1275 if (!(rsp->rel_flags & FLG_REL_LOAD) &&
1276 ((shndx == SHN_UNDEF) ||
1277 ((sdp->sd_ref == REF_DYN_NEED) &&
1278 ((sdp->sd_flags & FLG_SY_MVTOCOMM) == 0)))) {
1279 Conv_inv_buf_t inv_buf;
1280 Os_desc *osp = RELAUX_GET_OSDESC(rsp);
1281
1282 /*
1283 * If the relocation is against a SHT_SUNW_ANNOTATE
1284 * section - then silently ignore that the relocation
1285 * can not be resolved.
1286 */
1287 if (osp && (osp->os_shdr->sh_type == SHT_SUNW_ANNOTATE))
1288 return (0);
1289 ld_eprintf(ofl, ERR_WARNING, MSG_INTL(MSG_REL_EXTERNSYM),
1290 conv_reloc_amd64_type(rsp->rel_rtype, 0, &inv_buf),
1291 rsp->rel_isdesc->is_file->ifl_name,
1292 ld_reloc_sym_name(rsp), osp->os_name);
1293 return (1);
1294 }
1295
1296 /*
1297 * Perform relocation.
1298 */
1299 return (ld_add_actrel(0, rsp, ofl));
1300 }
1301
1302
1303 static uintptr_t
1304 ld_reloc_TLS(Boolean local, Rel_desc * rsp, Ofl_desc * ofl)
1305 {
1306 Word rtype = rsp->rel_rtype;
1307 Sym_desc *sdp = rsp->rel_sym;
1308 ofl_flag_t flags = ofl->ofl_flags;
1309 Gotndx *gnp;
1310
1311 /*
1312 * If we're building an executable - use either the IE or LE access
1313 * model. If we're building a shared object process any IE model.
1314 */
1315 if ((flags & FLG_OF_EXEC) || (IS_TLS_IE(rtype))) {
1316 /*
1317 * Set the DF_STATIC_TLS flag.
1318 */
1319 ofl->ofl_dtflags |= DF_STATIC_TLS;
1320
1321 if (!local || ((flags & FLG_OF_EXEC) == 0)) {
1322 /*
1323 * Assign a GOT entry for static TLS references.
1324 */
1325 if ((gnp = ld_find_got_ndx(sdp->sd_GOTndxs,
1326 GOT_REF_TLSIE, ofl, rsp)) == NULL) {
1327
1328 if (ld_assign_got_TLS(local, rsp, ofl, sdp,
1329 gnp, GOT_REF_TLSIE, FLG_REL_STLS,
1330 rtype, R_AMD64_TPOFF64, 0) == S_ERROR)
1331 return (S_ERROR);
1332 }
1333
1334 /*
1335 * IE access model.
1336 */
1337 if (IS_TLS_IE(rtype))
1338 return (ld_add_actrel(FLG_REL_STLS, rsp, ofl));
1339
1340 /*
1341 * Fixups are required for other executable models.
1342 */
1343 return (ld_add_actrel((FLG_REL_TLSFIX | FLG_REL_STLS),
1344 rsp, ofl));
1345 }
1346
1347 /*
1348 * LE access model.
1349 */
1350 if (IS_TLS_LE(rtype))
1351 return (ld_add_actrel(FLG_REL_STLS, rsp, ofl));
1352
1353 return (ld_add_actrel((FLG_REL_TLSFIX | FLG_REL_STLS),
1354 rsp, ofl));
1355 }
1356
1357 /*
1358 * Building a shared object.
1359 *
1360 * Assign a GOT entry for a dynamic TLS reference.
1361 */
1362 if (IS_TLS_LD(rtype) && ((gnp = ld_find_got_ndx(sdp->sd_GOTndxs,
1363 GOT_REF_TLSLD, ofl, rsp)) == NULL)) {
1364
1365 if (ld_assign_got_TLS(local, rsp, ofl, sdp, gnp, GOT_REF_TLSLD,
1366 FLG_REL_MTLS, rtype, R_AMD64_DTPMOD64, 0) == S_ERROR)
1367 return (S_ERROR);
1368
1369 } else if (IS_TLS_GD(rtype) &&
1370 ((gnp = ld_find_got_ndx(sdp->sd_GOTndxs, GOT_REF_TLSGD,
1371 ofl, rsp)) == NULL)) {
1372
1373 if (ld_assign_got_TLS(local, rsp, ofl, sdp, gnp, GOT_REF_TLSGD,
1374 FLG_REL_DTLS, rtype, R_AMD64_DTPMOD64,
1375 R_AMD64_DTPOFF64) == S_ERROR)
1376 return (S_ERROR);
1377 }
1378
1379 if (IS_TLS_LD(rtype))
1380 return (ld_add_actrel(FLG_REL_MTLS, rsp, ofl));
1381
1382 return (ld_add_actrel(FLG_REL_DTLS, rsp, ofl));
1383 }
1384
1385 /* ARGSUSED5 */
1386 static uintptr_t
1387 ld_assign_got_ndx(Alist **alpp, Gotndx *pgnp, Gotref gref, Ofl_desc *ofl,
1388 Rel_desc *rsp, Sym_desc *sdp)
1389 {
1390 Xword raddend;
1391 Gotndx gn, *gnp;
1392 Aliste idx;
1393 uint_t gotents;
1394
1395 raddend = rsp->rel_raddend;
1396 if (pgnp && (pgnp->gn_addend == raddend) && (pgnp->gn_gotref == gref))
1397 return (1);
1398
1399 if ((gref == GOT_REF_TLSGD) || (gref == GOT_REF_TLSLD))
1400 gotents = 2;
1401 else
1402 gotents = 1;
1403
1404 gn.gn_addend = raddend;
1405 gn.gn_gotndx = ofl->ofl_gotcnt;
1406 gn.gn_gotref = gref;
1407
1408 ofl->ofl_gotcnt += gotents;
1409
1410 if (gref == GOT_REF_TLSLD) {
1411 if (ofl->ofl_tlsldgotndx == NULL) {
1412 if ((gnp = libld_malloc(sizeof (Gotndx))) == NULL)
1413 return (S_ERROR);
1414 (void) memcpy(gnp, &gn, sizeof (Gotndx));
1415 ofl->ofl_tlsldgotndx = gnp;
1416 }
1417 return (1);
1418 }
1419
1420 idx = 0;
1421 for (ALIST_TRAVERSE(*alpp, idx, gnp)) {
1422 if (gnp->gn_addend > raddend)
1423 break;
1424 }
1425
1426 /*
1427 * GOT indexes are maintained on an Alist, where there is typically
1428 * only one index. The usage of this list is to scan the list to find
1429 * an index, and then apply that index immediately to a relocation.
1430 * Thus there are no external references to these GOT index structures
1431 * that can be compromised by the Alist being reallocated.
1432 */
1433 if (alist_insert(alpp, &gn, sizeof (Gotndx),
1434 AL_CNT_SDP_GOT, idx) == NULL)
1435 return (S_ERROR);
1436
1437 return (1);
1438 }
1439
1440 static void
1441 ld_assign_plt_ndx(Sym_desc * sdp, Ofl_desc *ofl)
1442 {
1443 sdp->sd_aux->sa_PLTndx = 1 + ofl->ofl_pltcnt++;
1444 sdp->sd_aux->sa_PLTGOTndx = ofl->ofl_gotcnt++;
1445 ofl->ofl_flags |= FLG_OF_BLDGOT;
1446 }
1447
1448 static uchar_t plt0_template[M_PLT_ENTSIZE] = {
1449 /* 0x00 PUSHQ GOT+8(%rip) */ 0xff, 0x35, 0x00, 0x00, 0x00, 0x00,
1450 /* 0x06 JMP *GOT+16(%rip) */ 0xff, 0x25, 0x00, 0x00, 0x00, 0x00,
1451 /* 0x0c NOP */ 0x90,
1452 /* 0x0d NOP */ 0x90,
1453 /* 0x0e NOP */ 0x90,
1454 /* 0x0f NOP */ 0x90
1455 };
1456
1457 /*
1458 * Initializes .got[0] with the _DYNAMIC symbol value.
1459 */
1460 static uintptr_t
1461 ld_fillin_gotplt(Ofl_desc *ofl)
1462 {
1463 int bswap = (ofl->ofl_flags1 & FLG_OF1_ENCDIFF) != 0;
1464
1465 if (ofl->ofl_osgot) {
1466 Sym_desc *sdp;
1467
1468 if ((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_DYNAMIC_U),
1469 SYM_NOHASH, NULL, ofl)) != NULL) {
1470 uchar_t *genptr;
1471
1472 genptr = ((uchar_t *)ofl->ofl_osgot->os_outdata->d_buf +
1473 (M_GOT_XDYNAMIC * M_GOT_ENTSIZE));
1474 /* LINTED */
1475 *(Xword *)genptr = sdp->sd_sym->st_value;
1476 if (bswap)
1477 /* LINTED */
1478 *(Xword *)genptr =
1479 /* LINTED */
1480 ld_bswap_Xword(*(Xword *)genptr);
1481 }
1482 }
1483
1484 /*
1485 * Fill in the reserved slot in the procedure linkage table the first
1486 * entry is:
1487 * 0x00 PUSHQ GOT+8(%rip) # GOT[1]
1488 * 0x06 JMP *GOT+16(%rip) # GOT[2]
1489 * 0x0c NOP
1490 * 0x0d NOP
1491 * 0x0e NOP
1492 * 0x0f NOP
1493 */
1494 if ((ofl->ofl_flags & FLG_OF_DYNAMIC) && ofl->ofl_osplt) {
1495 uchar_t *pltent;
1496 Xword val1;
1497
1498 pltent = (uchar_t *)ofl->ofl_osplt->os_outdata->d_buf;
1499 bcopy(plt0_template, pltent, sizeof (plt0_template));
1500
1501 /*
1502 * If '-z noreloc' is specified - skip the do_reloc_ld
1503 * stage.
1504 */
1505 if (!OFL_DO_RELOC(ofl))
1506 return (1);
1507
1508 /*
1509 * filin:
1510 * PUSHQ GOT + 8(%rip)
1511 *
1512 * Note: 0x06 below represents the offset to the
1513 * next instruction - which is what %rip will
1514 * be pointing at.
1515 */
1516 val1 = (ofl->ofl_osgot->os_shdr->sh_addr) +
1517 (M_GOT_XLINKMAP * M_GOT_ENTSIZE) -
1518 ofl->ofl_osplt->os_shdr->sh_addr - 0x06;
1519
1520 if (do_reloc_ld(&rdesc_r_amd64_gotpcrel, &pltent[0x02],
1521 &val1, syn_rdesc_sym_name, MSG_ORIG(MSG_SPECFIL_PLTENT),
1522 bswap, ofl->ofl_lml) == 0) {
1523 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_PLT_PLT0FAIL));
1524 return (S_ERROR);
1525 }
1526
1527 /*
1528 * filin:
1529 * JMP *GOT+16(%rip)
1530 */
1531 val1 = (ofl->ofl_osgot->os_shdr->sh_addr) +
1532 (M_GOT_XRTLD * M_GOT_ENTSIZE) -
1533 ofl->ofl_osplt->os_shdr->sh_addr - 0x0c;
1534
1535 if (do_reloc_ld(&rdesc_r_amd64_gotpcrel, &pltent[0x08],
1536 &val1, syn_rdesc_sym_name, MSG_ORIG(MSG_SPECFIL_PLTENT),
1537 bswap, ofl->ofl_lml) == 0) {
1538 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_PLT_PLT0FAIL));
1539 return (S_ERROR);
1540 }
1541 }
1542
1543 return (1);
1544 }
1545
1546
1547
1548 /*
1549 * Template for generating "void (*)(void)" function
1550 */
1551 static const uchar_t nullfunc_tmpl[] = { /* amd64 */
1552 /* 0x00 */ 0x55, /* pushq %rbp */
1553 /* 0x01 */ 0x48, 0x8b, 0xec, /* movq %rsp,%rbp */
1554 /* 0x04 */ 0x48, 0x8b, 0xe5, /* movq %rbp,%rsp */
1555 /* 0x07 */ 0x5d, /* popq %rbp */
1556 /* 0x08 */ 0xc3 /* ret */
1557 };
1558
1559
1560 /*
1561 * Function used to provide fill padding in SHF_EXECINSTR sections
1562 *
1563 * entry:
1564 *
1565 * base - base address of section being filled
1566 * offset - starting offset for fill within memory referenced by base
1567 * cnt - # bytes to be filled
1568 *
1569 * exit:
1570 * The fill has been completed.
1571 */
1572 static void
1573 execfill(void *base, off_t off, size_t cnt)
1574 {
1575 /*
1576 * 0x90 is an X86 NOP instruction in both 32 and 64-bit worlds.
1577 * There are no alignment constraints.
1578 */
1579 (void) memset(off + (char *)base, 0x90, cnt);
1580 }
1581
1582
1583 /*
1584 * Return the ld_targ definition for this target.
1585 */
1586 const Target *
1587 ld_targ_init_x86(void)
1588 {
1589 static const Target _ld_targ = {
1590 { /* Target_mach */
1591 M_MACH, /* m_mach */
1592 M_MACHPLUS, /* m_machplus */
1593 M_FLAGSPLUS, /* m_flagsplus */
1594 M_CLASS, /* m_class */
1595 M_DATA, /* m_data */
1596
1597 M_SEGM_ALIGN, /* m_segm_align */
1598 M_SEGM_ORIGIN, /* m_segm_origin */
1599 M_SEGM_AORIGIN, /* m_segm_aorigin */
1600 M_DATASEG_PERM, /* m_dataseg_perm */
1601 M_STACK_PERM, /* m_stack_perm */
1602 M_WORD_ALIGN, /* m_word_align */
1603 MSG_ORIG(MSG_PTH_RTLD_AMD64), /* m_def_interp */
1604
1605 /* Relocation type codes */
1606 M_R_ARRAYADDR, /* m_r_arrayaddr */
1607 M_R_COPY, /* m_r_copy */
1608 M_R_GLOB_DAT, /* m_r_glob_dat */
1609 M_R_JMP_SLOT, /* m_r_jmp_slot */
1610 M_R_NUM, /* m_r_num */
1611 M_R_NONE, /* m_r_none */
1612 M_R_RELATIVE, /* m_r_relative */
1613 M_R_REGISTER, /* m_r_register */
1614
1615 /* Relocation related constants */
1616 M_REL_DT_COUNT, /* m_rel_dt_count */
1617 M_REL_DT_ENT, /* m_rel_dt_ent */
1618 M_REL_DT_SIZE, /* m_rel_dt_size */
1619 M_REL_DT_TYPE, /* m_rel_dt_type */
1620 M_REL_SHT_TYPE, /* m_rel_sht_type */
1621
1622 /* GOT related constants */
1623 M_GOT_ENTSIZE, /* m_got_entsize */
1624 M_GOT_XNumber, /* m_got_xnumber */
1625
1626 /* PLT related constants */
1627 M_PLT_ALIGN, /* m_plt_align */
1628 M_PLT_ENTSIZE, /* m_plt_entsize */
1629 M_PLT_RESERVSZ, /* m_plt_reservsz */
1630 M_PLT_SHF_FLAGS, /* m_plt_shf_flags */
1631
1632 /* Section type of .eh_frame/.eh_frame_hdr sections */
1633 SHT_AMD64_UNWIND, /* m_sht_unwind */
1634
1635 M_DT_REGISTER, /* m_dt_register */
1636 },
1637 { /* Target_machid */
1638 M_ID_ARRAY, /* id_array */
1639 M_ID_BSS, /* id_bss */
1640 M_ID_CAP, /* id_cap */
1641 M_ID_CAPINFO, /* id_capinfo */
1642 M_ID_CAPCHAIN, /* id_capchain */
1643 M_ID_DATA, /* id_data */
1644 M_ID_DYNAMIC, /* id_dynamic */
1645 M_ID_DYNSORT, /* id_dynsort */
1646 M_ID_DYNSTR, /* id_dynstr */
1647 M_ID_DYNSYM, /* id_dynsym */
1648 M_ID_DYNSYM_NDX, /* id_dynsym_ndx */
1649 M_ID_GOT, /* id_got */
1650 M_ID_UNKNOWN, /* id_gotdata (unused) */
1651 M_ID_HASH, /* id_hash */
1652 M_ID_INTERP, /* id_interp */
1653 M_ID_LBSS, /* id_lbss */
1654 M_ID_LDYNSYM, /* id_ldynsym */
1655 M_ID_NOTE, /* id_note */
1656 M_ID_NULL, /* id_null */
1657 M_ID_PLT, /* id_plt */
1658 M_ID_REL, /* id_rel */
1659 M_ID_STRTAB, /* id_strtab */
1660 M_ID_SYMINFO, /* id_syminfo */
1661 M_ID_SYMTAB, /* id_symtab */
1662 M_ID_SYMTAB_NDX, /* id_symtab_ndx */
1663 M_ID_TEXT, /* id_text */
1664 M_ID_TLS, /* id_tls */
1665 M_ID_TLSBSS, /* id_tlsbss */
1666 M_ID_UNKNOWN, /* id_unknown */
1667 M_ID_UNWIND, /* id_unwind */
1668 M_ID_UNWINDHDR, /* id_unwindhdr */
1669 M_ID_USER, /* id_user */
1670 M_ID_VERSION, /* id_version */
1671 },
1672 { /* Target_nullfunc */
1673 nullfunc_tmpl, /* nf_template */
1674 sizeof (nullfunc_tmpl), /* nf_size */
1675 },
1676 { /* Target_fillfunc */
1677 execfill /* ff_execfill */
1678 },
1679 { /* Target_machrel */
1680 reloc_table,
1681
1682 ld_init_rel, /* mr_init_rel */
1683 ld_mach_eflags, /* mr_mach_eflags */
1684 ld_mach_make_dynamic, /* mr_mach_make_dynamic */
1685 ld_mach_update_odynamic, /* mr_mach_update_odynamic */
1686 ld_calc_plt_addr, /* mr_calc_plt_addr */
1687 ld_perform_outreloc, /* mr_perform_outreloc */
1688 ld_do_activerelocs, /* mr_do_activerelocs */
1689 ld_add_outrel, /* mr_add_outrel */
1690 NULL, /* mr_reloc_register */
1691 ld_reloc_local, /* mr_reloc_local */
1692 NULL, /* mr_reloc_GOTOP */
1693 ld_reloc_TLS, /* mr_reloc_TLS */
1694 NULL, /* mr_assign_got */
1695 ld_find_got_ndx, /* mr_find_got_ndx */
1696 ld_calc_got_offset, /* mr_calc_got_offset */
1697 ld_assign_got_ndx, /* mr_assign_got_ndx */
1698 ld_assign_plt_ndx, /* mr_assign_plt_ndx */
1699 NULL, /* mr_allocate_got */
1700 ld_fillin_gotplt, /* mr_fillin_gotplt */
1701 },
1702 { /* Target_machsym */
1703 NULL, /* ms_reg_check */
1704 NULL, /* ms_mach_sym_typecheck */
1705 NULL, /* ms_is_regsym */
1706 NULL, /* ms_reg_find */
1707 NULL /* ms_reg_enter */
1708 }
1709 };
1710
1711 return (&_ld_targ);
1712 }
unleashed repo fork