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 * x86 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_386.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 elf_rtbndr(Rt_map *, ulong_t, caddr_t); 54 55 int 56 elf_mach_flags_check(Rej_desc *rej, Ehdr *ehdr) 57 { 58 /* 59 * Check machine type and flags. 60 */ 61 if (ehdr->e_flags != 0) { 62 rej->rej_type = SGS_REJ_BADFLAG; 63 rej->rej_info = (uint_t)ehdr->e_flags; 64 return (0); 65 } 66 return (1); 67 } 68 69 void 70 ldso_plt_init(Rt_map * lmp) 71 { 72 /* 73 * There is no need to analyze ld.so because we don't map in any of 74 * its dependencies. However we may map these dependencies in later 75 * (as if ld.so had dlopened them), so initialize the plt and the 76 * permission information. 77 */ 78 if (PLTGOT(lmp)) 79 elf_plt_init((PLTGOT(lmp)), (caddr_t)lmp); 80 } 81 82 static const uchar_t dyn_plt_template[] = { 83 /* 0x00 */ 0x55, /* pushl %ebp */ 84 /* 0x01 */ 0x8b, 0xec, /* movl %esp, %ebp */ 85 /* 0x03 */ 0x68, 0x00, 0x00, 0x00, 0x00, /* pushl trace_fields */ 86 /* 0x08 */ 0xe9, 0xfc, 0xff, 0xff, 0xff, 0xff /* jmp elf_plt_trace */ 87 }; 88 int dyn_plt_ent_size = sizeof (dyn_plt_template); 89 90 /* 91 * the dynamic plt entry is: 92 * 93 * pushl %ebp 94 * movl %esp, %ebp 95 * pushl tfp 96 * jmp elf_plt_trace 97 * dyn_data: 98 * .align 4 99 * uintptr_t reflmp 100 * uintptr_t deflmp 101 * uint_t symndx 102 * uint_t sb_flags 103 * Sym symdef 104 */ 105 static caddr_t 106 elf_plt_trace_write(uint_t roffset, Rt_map *rlmp, Rt_map *dlmp, Sym *sym, 107 uint_t symndx, uint_t pltndx, caddr_t to, uint_t sb_flags, int *fail) 108 { 109 extern int elf_plt_trace(); 110 ulong_t got_entry; 111 uchar_t *dyn_plt; 112 uintptr_t *dyndata; 113 114 /* 115 * We only need to add the glue code if there is an auditing 116 * library that is interested in this binding. 117 */ 118 dyn_plt = (uchar_t *)((uintptr_t)AUDINFO(rlmp)->ai_dynplts + 119 (pltndx * dyn_plt_ent_size)); 120 121 /* 122 * Have we initialized this dynamic plt entry yet? If we haven't do it 123 * now. Otherwise this function has been called before, but from a 124 * different plt (ie. from another shared object). In that case 125 * we just set the plt to point to the new dyn_plt. 126 */ 127 if (*dyn_plt == 0) { 128 Sym *symp; 129 Word symvalue; 130 Lm_list *lml = LIST(rlmp); 131 132 (void) memcpy((void *)dyn_plt, dyn_plt_template, 133 sizeof (dyn_plt_template)); 134 dyndata = (uintptr_t *)((uintptr_t)dyn_plt + 135 ROUND(sizeof (dyn_plt_template), M_WORD_ALIGN)); 136 137 /* 138 * relocate: 139 * pushl dyn_data 140 */ 141 symvalue = (Word)dyndata; 142 if (do_reloc(R_386_32, &dyn_plt[4], &symvalue, 143 MSG_ORIG(MSG_SYM_LADYNDATA), 144 MSG_ORIG(MSG_SPECFIL_DYNPLT), lml) == 0) { 145 *fail = 1; 146 return (0); 147 } 148 149 /* 150 * jmps are relative, so I need to figure out the relative 151 * address to elf_plt_trace. 152 * 153 * relocating: 154 * jmp elf_plt_trace 155 */ 156 symvalue = (ulong_t)(elf_plt_trace) - (ulong_t)(dyn_plt + 9); 157 if (do_reloc(R_386_PC32, &dyn_plt[9], &symvalue, 158 MSG_ORIG(MSG_SYM_ELFPLTTRACE), 159 MSG_ORIG(MSG_SPECFIL_DYNPLT), lml) == 0) { 160 *fail = 1; 161 return (0); 162 } 163 164 *dyndata++ = (uintptr_t)rlmp; 165 *dyndata++ = (uintptr_t)dlmp; 166 *dyndata++ = (uint_t)symndx; 167 *dyndata++ = (uint_t)sb_flags; 168 symp = (Sym *)dyndata; 169 *symp = *sym; 170 symp->st_name += (Word)STRTAB(dlmp); 171 symp->st_value = (Addr)to; 172 } 173 174 got_entry = (ulong_t)roffset; 175 *(ulong_t *)got_entry = (ulong_t)dyn_plt; 176 return ((caddr_t)dyn_plt); 177 } 178 179 180 /* 181 * Function binding routine - invoked on the first call to a function through 182 * the procedure linkage table; 183 * passes first through an assembly language interface. 184 * 185 * Takes the offset into the relocation table of the associated 186 * relocation entry and the address of the link map (rt_private_map struct) 187 * for the entry. 188 * 189 * Returns the address of the function referenced after re-writing the PLT 190 * entry to invoke the function directly. 191 * 192 * On error, causes process to terminate with a signal. 193 */ 194 ulong_t 195 elf_bndr(Rt_map *lmp, ulong_t reloff, caddr_t from) 196 { 197 Rt_map *nlmp, *llmp; 198 ulong_t addr, symval, rsymndx; 199 char *name; 200 Rel *rptr; 201 Sym *sym, *nsym; 202 uint_t binfo, sb_flags = 0, dbg_class; 203 Slookup sl; 204 int entry, lmflags; 205 Lm_list *lml; 206 207 /* 208 * For compatibility with libthread (TI_VERSION 1) we track the entry 209 * value. A zero value indicates we have recursed into ld.so.1 to 210 * further process a locking request. Under this recursion we disable 211 * tsort and cleanup activities. 212 */ 213 entry = enter(); 214 215 lml = LIST(lmp); 216 if ((lmflags = lml->lm_flags) & LML_FLG_RTLDLM) { 217 dbg_class = dbg_desc->d_class; 218 dbg_desc->d_class = 0; 219 } 220 221 /* 222 * Perform some basic sanity checks. If we didn't get a load map or 223 * the relocation offset is invalid then its possible someone has walked 224 * over the .got entries or jumped to plt0 out of the blue. 225 */ 226 if (!lmp || ((reloff % sizeof (Rel)) != 0)) { 227 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_REL_PLTREF), 228 conv_reloc_386_type(R_386_JMP_SLOT, 0), 229 EC_NATPTR(lmp), EC_XWORD(reloff), EC_NATPTR(from)); 230 rtldexit(lml, 1); 231 } 232 233 /* 234 * Use relocation entry to get symbol table entry and symbol name. 235 */ 236 addr = (ulong_t)JMPREL(lmp); 237 rptr = (Rel *)(addr + reloff); 238 rsymndx = ELF_R_SYM(rptr->r_info); 239 sym = (Sym *)((ulong_t)SYMTAB(lmp) + (rsymndx * SYMENT(lmp))); 240 name = (char *)(STRTAB(lmp) + sym->st_name); 241 242 /* 243 * Determine the last link-map of this list, this'll be the starting 244 * point for any tsort() processing. 245 */ 246 llmp = lml->lm_tail; 247 248 /* 249 * Find definition for symbol. 250 */ 251 sl.sl_name = name; 252 sl.sl_cmap = lmp; 253 sl.sl_imap = lml->lm_head; 254 sl.sl_hash = 0; 255 sl.sl_rsymndx = rsymndx; 256 sl.sl_flags = LKUP_DEFT; 257 258 if ((nsym = lookup_sym(&sl, &nlmp, &binfo)) == 0) { 259 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_REL_NOSYM), NAME(lmp), 260 demangle(name)); 261 rtldexit(lml, 1); 262 } 263 264 symval = nsym->st_value; 265 if (!(FLAGS(nlmp) & FLG_RT_FIXED) && 266 (nsym->st_shndx != SHN_ABS)) 267 symval += ADDR(nlmp); 268 if ((lmp != nlmp) && ((FLAGS1(nlmp) & FL1_RT_NOINIFIN) == 0)) { 269 /* 270 * Record that this new link map is now bound to the caller. 271 */ 272 if (bind_one(lmp, nlmp, BND_REFER) == 0) 273 rtldexit(lml, 1); 274 } 275 276 if ((lml->lm_tflags | FLAGS1(lmp)) & LML_TFLG_AUD_SYMBIND) { 277 uint_t symndx = (((uintptr_t)nsym - 278 (uintptr_t)SYMTAB(nlmp)) / SYMENT(nlmp)); 279 symval = audit_symbind(lmp, nlmp, nsym, symndx, symval, 280 &sb_flags); 281 } 282 283 if (!(rtld_flags & RT_FL_NOBIND)) { 284 addr = rptr->r_offset; 285 if (!(FLAGS(lmp) & FLG_RT_FIXED)) 286 addr += ADDR(lmp); 287 if (((lml->lm_tflags | FLAGS1(lmp)) & 288 (LML_TFLG_AUD_PLTENTER | LML_TFLG_AUD_PLTEXIT)) && 289 AUDINFO(lmp)->ai_dynplts) { 290 int fail = 0; 291 uint_t pltndx = reloff / sizeof (Rel); 292 uint_t symndx = (((uintptr_t)nsym - 293 (uintptr_t)SYMTAB(nlmp)) / SYMENT(nlmp)); 294 295 symval = (ulong_t)elf_plt_trace_write(addr, lmp, nlmp, 296 nsym, symndx, pltndx, (caddr_t)symval, sb_flags, 297 &fail); 298 if (fail) 299 rtldexit(lml, 1); 300 } else { 301 /* 302 * Write standard PLT entry to jump directly 303 * to newly bound function. 304 */ 305 *(ulong_t *)addr = symval; 306 } 307 } 308 309 /* 310 * Print binding information and rebuild PLT entry. 311 */ 312 DBG_CALL(Dbg_bind_global(lmp, (Addr)from, (Off)(from - ADDR(lmp)), 313 (Xword)(reloff / sizeof (Rel)), PLT_T_FULL, nlmp, (Addr)symval, 314 nsym->st_value, name, binfo)); 315 316 /* 317 * Complete any processing for newly loaded objects. Note we don't 318 * know exactly where any new objects are loaded (we know the object 319 * that supplied the symbol, but others may have been loaded lazily as 320 * we searched for the symbol), so sorting starts from the last 321 * link-map know on entry to this routine. 322 */ 323 if (entry) 324 load_completion(llmp); 325 326 /* 327 * Some operations like dldump() or dlopen()'ing a relocatable object 328 * result in objects being loaded on rtld's link-map, make sure these 329 * objects are initialized also. 330 */ 331 if ((LIST(nlmp)->lm_flags & LML_FLG_RTLDLM) && LIST(nlmp)->lm_init) 332 load_completion(nlmp); 333 334 /* 335 * If the object we've bound to is in the process of being initialized 336 * by another thread, determine whether we should block. 337 */ 338 is_dep_ready(nlmp, lmp, DBG_WAIT_SYMBOL); 339 340 /* 341 * Make sure the object to which we've bound has had it's .init fired. 342 * Cleanup before return to user code. 343 */ 344 if (entry) { 345 is_dep_init(nlmp, lmp); 346 leave(lml); 347 } 348 349 if (lmflags & LML_FLG_RTLDLM) 350 dbg_desc->d_class = dbg_class; 351 352 return (symval); 353 } 354 355 356 /* 357 * When the relocation loop realizes that it's dealing with relative 358 * relocations in a shared object, it breaks into this tighter loop 359 * as an optimization. 360 */ 361 ulong_t 362 elf_reloc_relative(ulong_t relbgn, ulong_t relend, ulong_t relsiz, 363 ulong_t basebgn, ulong_t etext, ulong_t emap) 364 { 365 ulong_t roffset = ((Rel *)relbgn)->r_offset; 366 char rtype; 367 368 do { 369 roffset += basebgn; 370 371 /* 372 * If this relocation is against an address not mapped in, 373 * then break out of the relative relocation loop, falling 374 * back on the main relocation loop. 375 */ 376 if (roffset < etext || roffset > emap) 377 break; 378 379 /* 380 * Perform the actual relocation. 381 */ 382 *((ulong_t *)roffset) += basebgn; 383 384 relbgn += relsiz; 385 386 if (relbgn >= relend) 387 break; 388 389 rtype = ELF_R_TYPE(((Rel *)relbgn)->r_info); 390 roffset = ((Rel *)relbgn)->r_offset; 391 392 } while (rtype == R_386_RELATIVE); 393 394 return (relbgn); 395 } 396 397 /* 398 * This is the tightest loop for RELATIVE relocations for those 399 * objects built with the DT_RELACOUNT .dynamic entry. 400 */ 401 ulong_t 402 elf_reloc_relacount(ulong_t relbgn, ulong_t relacount, ulong_t relsiz, 403 ulong_t basebgn) 404 { 405 ulong_t roffset = ((Rel *) relbgn)->r_offset; 406 407 for (; relacount; relacount--) { 408 roffset += basebgn; 409 410 /* 411 * Perform the actual relocation. 412 */ 413 *((ulong_t *)roffset) += basebgn; 414 415 relbgn += relsiz; 416 417 roffset = ((Rel *)relbgn)->r_offset; 418 419 } 420 421 return (relbgn); 422 } 423 424 /* 425 * Read and process the relocations for one link object, we assume all 426 * relocation sections for loadable segments are stored contiguously in 427 * the file. 428 */ 429 int 430 elf_reloc(Rt_map *lmp, uint_t plt) 431 { 432 ulong_t relbgn, relend, relsiz, basebgn; 433 ulong_t pltbgn, pltend, _pltbgn, _pltend; 434 ulong_t roffset, rsymndx, psymndx = 0, etext = ETEXT(lmp); 435 ulong_t emap, dsymndx; 436 uchar_t rtype; 437 long value, pvalue; 438 Sym *symref, *psymref, *symdef, *psymdef; 439 char *name, *pname; 440 Rt_map *_lmp, *plmp; 441 int textrel = 0, ret = 1, noplt = 0; 442 int relacount = RELACOUNT(lmp), plthint = 0; 443 Rel *rel; 444 uint_t binfo, pbinfo; 445 Alist *bound = 0; 446 447 /* 448 * Although only necessary for lazy binding, initialize the first 449 * global offset entry to go to elf_rtbndr(). dbx(1) seems 450 * to find this useful. 451 */ 452 if ((plt == 0) && PLTGOT(lmp)) { 453 if ((ulong_t)PLTGOT(lmp) < etext) { 454 if (elf_set_prot(lmp, PROT_WRITE) == 0) 455 return (0); 456 textrel = 1; 457 } 458 elf_plt_init(PLTGOT(lmp), (caddr_t)lmp); 459 } 460 461 /* 462 * Initialize the plt start and end addresses. 463 */ 464 if ((pltbgn = (ulong_t)JMPREL(lmp)) != 0) 465 pltend = pltbgn + (ulong_t)(PLTRELSZ(lmp)); 466 467 468 relsiz = (ulong_t)(RELENT(lmp)); 469 basebgn = ADDR(lmp); 470 emap = ADDR(lmp) + MSIZE(lmp); 471 472 if (PLTRELSZ(lmp)) 473 plthint = PLTRELSZ(lmp) / relsiz; 474 475 /* 476 * If we've been called upon to promote an RTLD_LAZY object to an 477 * RTLD_NOW then we're only interested in scaning the .plt table. 478 * An uninitialized .plt is the case where the associated got entry 479 * points back to the plt itself. Determine the range of the real .plt 480 * entries using the _PROCEDURE_LINKAGE_TABLE_ symbol. 481 */ 482 if (plt) { 483 Slookup sl; 484 485 relbgn = pltbgn; 486 relend = pltend; 487 if (!relbgn || (relbgn == relend)) 488 return (1); 489 490 sl.sl_name = MSG_ORIG(MSG_SYM_PLT); 491 sl.sl_cmap = lmp; 492 sl.sl_imap = lmp; 493 sl.sl_hash = elf_hash(MSG_ORIG(MSG_SYM_PLT)); 494 sl.sl_rsymndx = 0; 495 sl.sl_flags = LKUP_DEFT; 496 497 if ((symdef = elf_find_sym(&sl, &_lmp, &binfo)) == 0) 498 return (1); 499 500 _pltbgn = symdef->st_value; 501 if (!(FLAGS(lmp) & FLG_RT_FIXED) && 502 (symdef->st_shndx != SHN_ABS)) 503 _pltbgn += basebgn; 504 _pltend = _pltbgn + (((PLTRELSZ(lmp) / relsiz)) * 505 M_PLT_ENTSIZE) + M_PLT_RESERVSZ; 506 507 } else { 508 /* 509 * The relocation sections appear to the run-time linker as a 510 * single table. Determine the address of the beginning and end 511 * of this table. There are two different interpretations of 512 * the ABI at this point: 513 * 514 * o The REL table and its associated RELSZ indicate the 515 * concatenation of *all* relocation sections (this is the 516 * model our link-editor constructs). 517 * 518 * o The REL table and its associated RELSZ indicate the 519 * concatenation of all *but* the .plt relocations. These 520 * relocations are specified individually by the JMPREL and 521 * PLTRELSZ entries. 522 * 523 * Determine from our knowledege of the relocation range and 524 * .plt range, the range of the total relocation table. Note 525 * that one other ABI assumption seems to be that the .plt 526 * relocations always follow any other relocations, the 527 * following range checking drops that assumption. 528 */ 529 relbgn = (ulong_t)(REL(lmp)); 530 relend = relbgn + (ulong_t)(RELSZ(lmp)); 531 if (pltbgn) { 532 if (!relbgn || (relbgn > pltbgn)) 533 relbgn = pltbgn; 534 if (!relbgn || (relend < pltend)) 535 relend = pltend; 536 } 537 } 538 if (!relbgn || (relbgn == relend)) { 539 DBG_CALL(Dbg_reloc_run(lmp, 0, plt, DBG_REL_NONE)); 540 return (1); 541 } 542 DBG_CALL(Dbg_reloc_run(lmp, M_REL_SHT_TYPE, plt, DBG_REL_START)); 543 544 /* 545 * If we're processing a dynamic executable in lazy mode there is no 546 * need to scan the .rel.plt table, however if we're processing a shared 547 * object in lazy mode the .got addresses associated to each .plt must 548 * be relocated to reflect the location of the shared object. 549 */ 550 if (pltbgn && ((MODE(lmp) & RTLD_NOW) == 0) && 551 (FLAGS(lmp) & FLG_RT_FIXED)) 552 noplt = 1; 553 554 /* 555 * Loop through relocations. 556 */ 557 while (relbgn < relend) { 558 uint_t sb_flags = 0; 559 560 rtype = ELF_R_TYPE(((Rel *)relbgn)->r_info); 561 562 /* 563 * If this is a RELATIVE relocation in a shared object (the 564 * common case), and if we are not debugging, then jump into a 565 * tighter relocation loop (elf_reloc_relative). Only make the 566 * jump if we've been given a hint on the number of relocations. 567 */ 568 if ((rtype == R_386_RELATIVE) && 569 ((FLAGS(lmp) & FLG_RT_FIXED) == 0) && (DBG_ENABLED == 0)) { 570 /* 571 * It's possible that the relative relocation block 572 * has relocations against the text segment as well 573 * as the data segment. Since our optimized relocation 574 * engine does not check which segment the relocation 575 * is against - just mprotect it now if it's been 576 * marked as containing TEXTREL's. 577 */ 578 if ((textrel == 0) && (FLAGS1(lmp) & FL1_RT_TEXTREL)) { 579 if (elf_set_prot(lmp, PROT_WRITE) == 0) { 580 ret = 0; 581 break; 582 } 583 textrel = 1; 584 } 585 586 if (relacount) { 587 relbgn = elf_reloc_relacount(relbgn, relacount, 588 relsiz, basebgn); 589 relacount = 0; 590 } else { 591 relbgn = elf_reloc_relative(relbgn, relend, 592 relsiz, basebgn, etext, emap); 593 } 594 if (relbgn >= relend) 595 break; 596 rtype = ELF_R_TYPE(((Rel *)relbgn)->r_info); 597 } 598 599 roffset = ((Rel *)relbgn)->r_offset; 600 601 /* 602 * If this is a shared object, add the base address to offset. 603 */ 604 if (!(FLAGS(lmp) & FLG_RT_FIXED)) { 605 606 /* 607 * If we're processing lazy bindings, we have to step 608 * through the plt entries and add the base address 609 * to the corresponding got entry. 610 */ 611 if (plthint && (plt == 0) && 612 (rtype == R_386_JMP_SLOT) && 613 ((MODE(lmp) & RTLD_NOW) == 0)) { 614 relbgn = elf_reloc_relacount(relbgn, 615 plthint, relsiz, basebgn); 616 plthint = 0; 617 continue; 618 } 619 roffset += basebgn; 620 } 621 622 rsymndx = ELF_R_SYM(((Rel *)relbgn)->r_info); 623 rel = (Rel *)relbgn; 624 relbgn += relsiz; 625 626 /* 627 * Optimizations. 628 */ 629 if (rtype == R_386_NONE) 630 continue; 631 if (noplt && ((ulong_t)rel >= pltbgn) && 632 ((ulong_t)rel < pltend)) { 633 relbgn = pltend; 634 continue; 635 } 636 637 /* 638 * If we're promoting plts determine if this one has already 639 * been written. 640 */ 641 if (plt) { 642 if ((*(ulong_t *)roffset < _pltbgn) || 643 (*(ulong_t *)roffset > _pltend)) 644 continue; 645 } 646 647 /* 648 * If this relocation is not against part of the image 649 * mapped into memory we skip it. 650 */ 651 if ((roffset < ADDR(lmp)) || (roffset > (ADDR(lmp) + 652 MSIZE(lmp)))) { 653 elf_reloc_bad(lmp, (void *)rel, rtype, roffset, 654 rsymndx); 655 continue; 656 } 657 658 binfo = 0; 659 /* 660 * If a symbol index is specified then get the symbol table 661 * entry, locate the symbol definition, and determine its 662 * address. 663 */ 664 if (rsymndx) { 665 /* 666 * Get the local symbol table entry. 667 */ 668 symref = (Sym *)((ulong_t)SYMTAB(lmp) + 669 (rsymndx * SYMENT(lmp))); 670 671 /* 672 * If this is a local symbol, just use the base address. 673 * (we should have no local relocations in the 674 * executable). 675 */ 676 if (ELF_ST_BIND(symref->st_info) == STB_LOCAL) { 677 value = basebgn; 678 name = (char *)0; 679 680 /* 681 * Special case TLS relocations. 682 */ 683 if (rtype == R_386_TLS_DTPMOD32) { 684 /* 685 * Use the TLS modid. 686 */ 687 value = TLSMODID(lmp); 688 689 } else if (rtype == R_386_TLS_TPOFF) { 690 if ((value = elf_static_tls(lmp, symref, 691 rel, rtype, 0, roffset, 0)) == 0) { 692 ret = 0; 693 break; 694 } 695 } 696 } else { 697 /* 698 * If the symbol index is equal to the previous 699 * symbol index relocation we processed then 700 * reuse the previous values. (Note that there 701 * have been cases where a relocation exists 702 * against a copy relocation symbol, our ld(1) 703 * should optimize this away, but make sure we 704 * don't use the same symbol information should 705 * this case exist). 706 */ 707 if ((rsymndx == psymndx) && 708 (rtype != R_386_COPY)) { 709 /* LINTED */ 710 if (psymdef == 0) { 711 DBG_CALL(Dbg_bind_weak(lmp, 712 (Addr)roffset, (Addr) 713 (roffset - basebgn), name)); 714 continue; 715 } 716 /* LINTED */ 717 value = pvalue; 718 /* LINTED */ 719 name = pname; 720 /* LINTED */ 721 symdef = psymdef; 722 /* LINTED */ 723 symref = psymref; 724 /* LINTED */ 725 _lmp = plmp; 726 /* LINTED */ 727 binfo = pbinfo; 728 729 if ((LIST(_lmp)->lm_tflags | 730 FLAGS1(_lmp)) & 731 LML_TFLG_AUD_SYMBIND) { 732 value = audit_symbind(lmp, _lmp, 733 /* LINTED */ 734 symdef, dsymndx, value, 735 &sb_flags); 736 } 737 } else { 738 Slookup sl; 739 uchar_t bind; 740 741 /* 742 * Lookup the symbol definition. 743 */ 744 name = (char *)(STRTAB(lmp) + 745 symref->st_name); 746 747 sl.sl_name = name; 748 sl.sl_cmap = lmp; 749 sl.sl_imap = 0; 750 sl.sl_hash = 0; 751 sl.sl_rsymndx = rsymndx; 752 753 if (rtype == R_386_COPY) 754 sl.sl_flags = LKUP_COPY; 755 else 756 sl.sl_flags = LKUP_DEFT; 757 758 sl.sl_flags |= LKUP_ALLCNTLIST; 759 760 if (rtype != R_386_JMP_SLOT) 761 sl.sl_flags |= LKUP_SPEC; 762 763 bind = ELF_ST_BIND(symref->st_info); 764 if (bind == STB_WEAK) 765 sl.sl_flags |= LKUP_WEAK; 766 767 symdef = lookup_sym(&sl, &_lmp, &binfo); 768 769 /* 770 * If the symbol is not found and the 771 * reference was not to a weak symbol, 772 * report an error. Weak references 773 * may be unresolved. 774 * chkmsg: MSG_INTL(MSG_LDD_SYM_NFOUND) 775 */ 776 /* BEGIN CSTYLED */ 777 if (symdef == 0) { 778 Lm_list *lml = LIST(lmp); 779 780 if (bind != STB_WEAK) { 781 if (lml->lm_flags & 782 LML_FLG_IGNRELERR) { 783 continue; 784 } else if (lml->lm_flags & 785 LML_FLG_TRC_WARN) { 786 (void) printf(MSG_INTL( 787 MSG_LDD_SYM_NFOUND), 788 demangle(name), 789 NAME(lmp)); 790 continue; 791 } else { 792 DBG_CALL(Dbg_reloc_in(lml, 793 ELF_DBG_RTLD, M_MACH, 794 M_REL_SHT_TYPE, rel, 795 NULL, name)); 796 eprintf(lml, ERR_FATAL, 797 MSG_INTL(MSG_REL_NOSYM), 798 NAME(lmp), 799 demangle(name)); 800 ret = 0; 801 break; 802 } 803 } else { 804 psymndx = rsymndx; 805 psymdef = 0; 806 807 DBG_CALL(Dbg_bind_weak(lmp, 808 (Addr)roffset, (Addr) 809 (roffset - basebgn), name)); 810 continue; 811 } 812 } 813 /* END CSTYLED */ 814 815 /* 816 * If symbol was found in an object 817 * other than the referencing object 818 * then record the binding. 819 */ 820 if ((lmp != _lmp) && ((FLAGS1(_lmp) & 821 FL1_RT_NOINIFIN) == 0)) { 822 if (alist_test(&bound, _lmp, 823 sizeof (Rt_map *), 824 AL_CNT_RELBIND) == 0) { 825 ret = 0; 826 break; 827 } 828 } 829 830 /* 831 * Calculate the location of definition; 832 * symbol value plus base address of 833 * containing shared object. 834 */ 835 if (IS_SIZE(rtype)) 836 value = symdef->st_size; 837 else 838 value = symdef->st_value; 839 840 if (!(FLAGS(_lmp) & FLG_RT_FIXED) && 841 !(IS_SIZE(rtype)) && 842 (symdef->st_shndx != SHN_ABS) && 843 (ELF_ST_TYPE(symdef->st_info) != 844 STT_TLS)) 845 value += ADDR(_lmp); 846 847 /* 848 * Retain this symbol index and the 849 * value in case it can be used for the 850 * subsequent relocations. 851 */ 852 if (rtype != R_386_COPY) { 853 psymndx = rsymndx; 854 pvalue = value; 855 pname = name; 856 psymdef = symdef; 857 psymref = symref; 858 plmp = _lmp; 859 pbinfo = binfo; 860 } 861 if ((LIST(_lmp)->lm_tflags | 862 FLAGS1(_lmp)) & 863 LML_TFLG_AUD_SYMBIND) { 864 dsymndx = (((uintptr_t)symdef - 865 (uintptr_t)SYMTAB(_lmp)) / 866 SYMENT(_lmp)); 867 value = audit_symbind(lmp, _lmp, 868 symdef, dsymndx, value, 869 &sb_flags); 870 } 871 } 872 873 /* 874 * If relocation is PC-relative, subtract 875 * offset address. 876 */ 877 if (IS_PC_RELATIVE(rtype)) 878 value -= roffset; 879 880 /* 881 * Special case TLS relocations. 882 */ 883 if (rtype == R_386_TLS_DTPMOD32) { 884 /* 885 * Relocation value is the TLS modid. 886 */ 887 value = TLSMODID(_lmp); 888 889 } else if (rtype == R_386_TLS_TPOFF) { 890 if ((value = elf_static_tls(_lmp, 891 symdef, rel, rtype, name, roffset, 892 value)) == 0) { 893 ret = 0; 894 break; 895 } 896 } 897 } 898 } else { 899 /* 900 * Special cases. 901 */ 902 if (rtype == R_386_TLS_DTPMOD32) { 903 /* 904 * TLS relocation value is the TLS modid. 905 */ 906 value = TLSMODID(lmp); 907 } else 908 value = basebgn; 909 name = (char *)0; 910 } 911 912 DBG_CALL(Dbg_reloc_in(LIST(lmp), ELF_DBG_RTLD, M_MACH, 913 M_REL_SHT_TYPE, rel, NULL, name)); 914 915 /* 916 * If this object has relocations in the text segment, turn 917 * off the write protect. 918 */ 919 if ((roffset < etext) && (textrel == 0)) { 920 if (elf_set_prot(lmp, PROT_WRITE) == 0) { 921 ret = 0; 922 break; 923 } 924 textrel = 1; 925 } 926 927 /* 928 * Call relocation routine to perform required relocation. 929 */ 930 switch (rtype) { 931 case R_386_COPY: 932 if (elf_copy_reloc(name, symref, lmp, (void *)roffset, 933 symdef, _lmp, (const void *)value) == 0) 934 ret = 0; 935 break; 936 case R_386_JMP_SLOT: 937 if (((LIST(lmp)->lm_tflags | FLAGS1(lmp)) & 938 (LML_TFLG_AUD_PLTENTER | LML_TFLG_AUD_PLTEXIT)) && 939 AUDINFO(lmp)->ai_dynplts) { 940 int fail = 0; 941 int pltndx = (((ulong_t)rel - 942 (uintptr_t)JMPREL(lmp)) / relsiz); 943 int symndx = (((uintptr_t)symdef - 944 (uintptr_t)SYMTAB(_lmp)) / SYMENT(_lmp)); 945 946 (void) elf_plt_trace_write(roffset, lmp, _lmp, 947 symdef, symndx, pltndx, (caddr_t)value, 948 sb_flags, &fail); 949 if (fail) 950 ret = 0; 951 } else { 952 /* 953 * Write standard PLT entry to jump directly 954 * to newly bound function. 955 */ 956 DBG_CALL(Dbg_reloc_apply_val(LIST(lmp), 957 ELF_DBG_RTLD, (Xword)roffset, 958 (Xword)value)); 959 *(ulong_t *)roffset = value; 960 } 961 break; 962 default: 963 /* 964 * Write the relocation out. 965 */ 966 if (do_reloc(rtype, (uchar_t *)roffset, (Word *)&value, 967 name, NAME(lmp), LIST(lmp)) == 0) 968 ret = 0; 969 970 DBG_CALL(Dbg_reloc_apply_val(LIST(lmp), ELF_DBG_RTLD, 971 (Xword)roffset, (Xword)value)); 972 } 973 974 if ((ret == 0) && 975 ((LIST(lmp)->lm_flags & LML_FLG_TRC_WARN) == 0)) 976 break; 977 978 if (binfo) { 979 DBG_CALL(Dbg_bind_global(lmp, (Addr)roffset, 980 (Off)(roffset - basebgn), (Xword)(-1), PLT_T_FULL, 981 _lmp, (Addr)value, symdef->st_value, name, binfo)); 982 } 983 } 984 985 return (relocate_finish(lmp, bound, textrel, ret)); 986 } 987 988 /* 989 * Initialize the first few got entries so that function calls go to 990 * elf_rtbndr: 991 * 992 * GOT[GOT_XLINKMAP] = the address of the link map 993 * GOT[GOT_XRTLD] = the address of rtbinder 994 */ 995 void 996 elf_plt_init(void *got, caddr_t l) 997 { 998 uint_t *_got; 999 /* LINTED */ 1000 Rt_map *lmp = (Rt_map *)l; 1001 1002 _got = (uint_t *)got + M_GOT_XLINKMAP; 1003 *_got = (uint_t)lmp; 1004 _got = (uint_t *)got + M_GOT_XRTLD; 1005 *_got = (uint_t)elf_rtbndr; 1006 } 1007 1008 /* 1009 * For SVR4 Intel compatability. USL uses /usr/lib/libc.so.1 as the run-time 1010 * linker, so the interpreter's address will differ from /usr/lib/ld.so.1. 1011 * Further, USL has special _iob[] and _ctype[] processing that makes up for the 1012 * fact that these arrays do not have associated copy relocations. So we try 1013 * and make up for that here. Any relocations found will be added to the global 1014 * copy relocation list and will be processed in setup(). 1015 */ 1016 static int 1017 _elf_copy_reloc(const char *name, Rt_map *rlmp, Rt_map *dlmp) 1018 { 1019 Sym *symref, *symdef; 1020 caddr_t ref, def; 1021 Rt_map *_lmp; 1022 Rel rel; 1023 Slookup sl; 1024 uint_t binfo; 1025 1026 /* 1027 * Determine if the special symbol exists as a reference in the dynamic 1028 * executable, and that an associated definition exists in libc.so.1. 1029 */ 1030 sl.sl_name = name; 1031 sl.sl_cmap = rlmp; 1032 sl.sl_imap = rlmp; 1033 sl.sl_hash = 0; 1034 sl.sl_rsymndx = 0; 1035 sl.sl_flags = LKUP_FIRST; 1036 1037 if ((symref = lookup_sym(&sl, &_lmp, &binfo)) == 0) 1038 return (1); 1039 1040 sl.sl_imap = dlmp; 1041 sl.sl_flags = LKUP_DEFT; 1042 1043 if ((symdef = lookup_sym(&sl, &_lmp, &binfo)) == 0) 1044 return (1); 1045 if (strcmp(NAME(_lmp), MSG_ORIG(MSG_PTH_LIBC))) 1046 return (1); 1047 1048 /* 1049 * Determine the reference and definition addresses. 1050 */ 1051 ref = (void *)(symref->st_value); 1052 if (!(FLAGS(rlmp) & FLG_RT_FIXED)) 1053 ref += ADDR(rlmp); 1054 def = (void *)(symdef->st_value); 1055 if (!(FLAGS(_lmp) & FLG_RT_FIXED)) 1056 def += ADDR(_lmp); 1057 1058 /* 1059 * Set up a relocation entry for debugging and call the generic copy 1060 * relocation function to provide symbol size error checking and to 1061 * record the copy relocation that must be performed. 1062 */ 1063 rel.r_offset = (Addr)ref; 1064 rel.r_info = (Word)R_386_COPY; 1065 DBG_CALL(Dbg_reloc_in(LIST(rlmp), ELF_DBG_RTLD, M_MACH, M_REL_SHT_TYPE, 1066 &rel, NULL, name)); 1067 1068 return (elf_copy_reloc((char *)name, symref, rlmp, (void *)ref, symdef, 1069 _lmp, (void *)def)); 1070 } 1071 1072 int 1073 elf_copy_gen(Rt_map *lmp) 1074 { 1075 if (interp && ((ulong_t)interp->i_faddr != 1076 r_debug.rtd_rdebug.r_ldbase) && 1077 !(strcmp(interp->i_name, MSG_ORIG(MSG_PTH_LIBC)))) { 1078 1079 DBG_CALL(Dbg_reloc_run(lmp, M_REL_SHT_TYPE, 0, 1080 DBG_REL_START)); 1081 1082 if (_elf_copy_reloc(MSG_ORIG(MSG_SYM_CTYPE), lmp, 1083 (Rt_map *)NEXT(lmp)) == 0) 1084 return (0); 1085 if (_elf_copy_reloc(MSG_ORIG(MSG_SYM_IOB), lmp, 1086 (Rt_map *)NEXT(lmp)) == 0) 1087 return (0); 1088 } 1089 return (1); 1090 } 1091 1092 /* 1093 * Plt writing interface to allow debugging initialization to be generic. 1094 */ 1095 Pltbindtype 1096 /* ARGSUSED1 */ 1097 elf_plt_write(uintptr_t addr, uintptr_t vaddr, void *rptr, uintptr_t symval, 1098 Xword pltndx) 1099 { 1100 Rel *rel = (Rel*)rptr; 1101 uintptr_t pltaddr; 1102 1103 pltaddr = addr + rel->r_offset; 1104 *(ulong_t *)pltaddr = (ulong_t)symval; 1105 DBG_CALL(pltcntfull++); 1106 return (PLT_T_FULL); 1107 } 1108 1109 /* 1110 * Provide a machine specific interface to the conversion routine. By calling 1111 * the machine specific version, rather than the generic version, we insure that 1112 * the data tables/strings for all known machine versions aren't dragged into 1113 * ld.so.1. 1114 */ 1115 const char * 1116 _conv_reloc_type(uint_t rel) 1117 { 1118 return (conv_reloc_386_type(rel, 0)); 1119 } 1120