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 * Object file dependent support for ELF objects. 33 */ 34 #include "_synonyms.h" 35 36 #include <stdio.h> 37 #include <sys/procfs.h> 38 #include <sys/mman.h> 39 #include <sys/debug.h> 40 #include <string.h> 41 #include <limits.h> 42 #include <dlfcn.h> 43 #include <debug.h> 44 #include <conv.h> 45 #include "_rtld.h" 46 #include "_audit.h" 47 #include "_elf.h" 48 #include "msg.h" 49 50 /* 51 * Default and secure dependency search paths. 52 */ 53 static Pnode elf_dflt_dirs[] = { 54 #if defined(_ELF64) 55 #ifndef SGS_PRE_UNIFIED_PROCESS 56 { MSG_ORIG(MSG_PTH_LIB_64), 0, MSG_PTH_LIB_64_SIZE, 57 LA_SER_DEFAULT, 0, &elf_dflt_dirs[1] }, 58 #endif 59 { MSG_ORIG(MSG_PTH_USRLIB_64), 0, MSG_PTH_USRLIB_64_SIZE, 60 LA_SER_DEFAULT, 0, 0 } 61 #else 62 #ifndef SGS_PRE_UNIFIED_PROCESS 63 { MSG_ORIG(MSG_PTH_LIB), 0, MSG_PTH_LIB_SIZE, 64 LA_SER_DEFAULT, 0, &elf_dflt_dirs[1] }, 65 #endif 66 { MSG_ORIG(MSG_PTH_USRLIB), 0, MSG_PTH_USRLIB_SIZE, 67 LA_SER_DEFAULT, 0, 0 } 68 #endif 69 }; 70 71 static Pnode elf_secure_dirs[] = { 72 #if defined(_ELF64) 73 #ifndef SGS_PRE_UNIFIED_PROCESS 74 { MSG_ORIG(MSG_PTH_LIBSE_64), 0, MSG_PTH_LIBSE_64_SIZE, 75 LA_SER_SECURE, 0, &elf_secure_dirs[1] }, 76 #endif 77 { MSG_ORIG(MSG_PTH_USRLIBSE_64), 0, 78 MSG_PTH_USRLIBSE_64_SIZE, 79 LA_SER_SECURE, 0, 0 } 80 #else 81 #ifndef SGS_PRE_UNIFIED_PROCESS 82 { MSG_ORIG(MSG_PTH_LIBSE), 0, MSG_PTH_LIBSE_SIZE, 83 LA_SER_SECURE, 0, &elf_secure_dirs[1] }, 84 #endif 85 { MSG_ORIG(MSG_PTH_USRLIBSE), 0, MSG_PTH_USRLIBSE_SIZE, 86 LA_SER_SECURE, 0, 0 } 87 #endif 88 }; 89 90 /* 91 * Defines for local functions. 92 */ 93 static Pnode *elf_fix_name(const char *, Rt_map *, uint_t); 94 static int elf_are_u(Rej_desc *); 95 static void elf_dladdr(ulong_t, Rt_map *, Dl_info *, void **, int); 96 static ulong_t elf_entry_pt(void); 97 static char *elf_get_so(const char *, const char *); 98 static Rt_map *elf_map_so(Lm_list *, Aliste, const char *, const char *, int); 99 static int elf_needed(Lm_list *, Aliste, Rt_map *); 100 static void elf_unmap_so(Rt_map *); 101 static int elf_verify_vers(const char *, Rt_map *, Rt_map *); 102 103 /* 104 * Functions and data accessed through indirect pointers. 105 */ 106 Fct elf_fct = { 107 elf_are_u, 108 elf_entry_pt, 109 elf_map_so, 110 elf_unmap_so, 111 elf_needed, 112 lookup_sym, 113 elf_reloc, 114 elf_dflt_dirs, 115 elf_secure_dirs, 116 elf_fix_name, 117 elf_get_so, 118 elf_dladdr, 119 dlsym_handle, 120 elf_verify_vers, 121 elf_set_prot 122 }; 123 124 125 /* 126 * Redefine NEEDED name if necessary. 127 */ 128 static Pnode * 129 elf_fix_name(const char *name, Rt_map *clmp, uint_t orig) 130 { 131 /* 132 * For ABI compliance, if we are asked for ld.so.1, then really give 133 * them libsys.so.1 (the SONAME of libsys.so.1 is ld.so.1). 134 */ 135 if (((*name == '/') && 136 /* BEGIN CSTYLED */ 137 #if defined(_ELF64) 138 (strcmp(name, MSG_ORIG(MSG_PTH_RTLD_64)) == 0)) || 139 #else 140 (strcmp(name, MSG_ORIG(MSG_PTH_RTLD)) == 0)) || 141 #endif 142 (strcmp(name, MSG_ORIG(MSG_FIL_RTLD)) == 0)) { 143 /* END CSTYLED */ 144 Pnode *pnp; 145 146 DBG_CALL(Dbg_file_fixname(LIST(clmp), name, 147 MSG_ORIG(MSG_PTH_LIBSYS))); 148 if (((pnp = calloc(sizeof (Pnode), 1)) == 0) || 149 ((pnp->p_name = strdup(MSG_ORIG(MSG_PTH_LIBSYS))) == 0)) { 150 if (pnp) 151 free(pnp); 152 return (0); 153 } 154 pnp->p_len = MSG_PTH_LIBSYS_SIZE; 155 pnp->p_orig = (orig & PN_SER_MASK); 156 return (pnp); 157 } 158 159 return (expand_paths(clmp, name, orig, 0)); 160 } 161 162 /* 163 * Determine if we have been given an ELF file and if so determine if the file 164 * is compatible. Returns 1 if true, else 0 and sets the reject descriptor 165 * with associated error information. 166 */ 167 static int 168 elf_are_u(Rej_desc *rej) 169 { 170 Ehdr *ehdr; 171 172 /* 173 * Determine if we're an elf file. If not simply return, we don't set 174 * any rejection information as this test allows use to scroll through 175 * the objects we support (ELF, AOUT). 176 */ 177 if (fmap->fm_fsize < sizeof (Ehdr) || 178 fmap->fm_maddr[EI_MAG0] != ELFMAG0 || 179 fmap->fm_maddr[EI_MAG1] != ELFMAG1 || 180 fmap->fm_maddr[EI_MAG2] != ELFMAG2 || 181 fmap->fm_maddr[EI_MAG3] != ELFMAG3) { 182 return (0); 183 } 184 185 /* 186 * Check class and encoding. 187 */ 188 /* LINTED */ 189 ehdr = (Ehdr *)fmap->fm_maddr; 190 if (ehdr->e_ident[EI_CLASS] != M_CLASS) { 191 rej->rej_type = SGS_REJ_CLASS; 192 rej->rej_info = (uint_t)ehdr->e_ident[EI_CLASS]; 193 return (0); 194 } 195 if (ehdr->e_ident[EI_DATA] != M_DATA) { 196 rej->rej_type = SGS_REJ_DATA; 197 rej->rej_info = (uint_t)ehdr->e_ident[EI_DATA]; 198 return (0); 199 } 200 if ((ehdr->e_type != ET_REL) && (ehdr->e_type != ET_EXEC) && 201 (ehdr->e_type != ET_DYN)) { 202 rej->rej_type = SGS_REJ_TYPE; 203 rej->rej_info = (uint_t)ehdr->e_type; 204 return (0); 205 } 206 207 /* 208 * Verify machine specific flags, and hardware capability requirements. 209 */ 210 if ((elf_mach_flags_check(rej, ehdr) == 0) || 211 ((rtld_flags2 & RT_FL2_HWCAP) && (hwcap_check(rej, ehdr) == 0))) 212 return (0); 213 214 /* 215 * Verify ELF version. ??? is this too restrictive ??? 216 */ 217 if (ehdr->e_version > EV_CURRENT) { 218 rej->rej_type = SGS_REJ_VERSION; 219 rej->rej_info = (uint_t)ehdr->e_version; 220 return (0); 221 } 222 return (1); 223 } 224 225 /* 226 * The runtime linker employs lazy loading to provide the libraries needed for 227 * debugging, preloading .o's and dldump(). As these are seldom used, the 228 * standard startup of ld.so.1 doesn't initialize all the information necessary 229 * to perform plt relocation on ld.so.1's link-map. The first time lazy loading 230 * is called we get here to perform these initializations: 231 * 232 * o elf_needed() is called to set up the DYNINFO() indexes for each lazy 233 * dependency. Typically, for all other objects, this is called during 234 * analyze_so(), but as ld.so.1 is set-contained we skip this processing. 235 * 236 * o For intel, ld.so.1's JMPSLOT relocations need relative updates. These 237 * are by default skipped thus delaying all relative relocation processing 238 * on every invocation of ld.so.1. 239 */ 240 int 241 elf_rtld_load() 242 { 243 Lm_list *lml = &lml_rtld; 244 Rt_map *lmp = lml->lm_head; 245 246 if (lml->lm_flags & LML_FLG_PLTREL) 247 return (1); 248 249 /* 250 * As we need to refer to the DYNINFO() information, insure that it has 251 * been initialized. 252 */ 253 if (elf_needed(lml, ALO_DATA, lmp) == 0) 254 return (0); 255 256 #if defined(__i386) 257 /* 258 * This is a kludge to give ld.so.1 a performance benefit on i386. 259 * It's based around two factors. 260 * 261 * o JMPSLOT relocations (PLT's) actually need a relative relocation 262 * applied to the GOT entry so that they can find PLT0. 263 * 264 * o ld.so.1 does not exercise *any* PLT's before it has made a call 265 * to elf_lazy_load(). This is because all dynamic dependencies 266 * are recorded as lazy dependencies. 267 */ 268 (void) elf_reloc_relacount((ulong_t)JMPREL(lmp), 269 (ulong_t)(PLTRELSZ(lmp) / RELENT(lmp)), (ulong_t)RELENT(lmp), 270 (ulong_t)ADDR(lmp)); 271 #endif 272 273 lml->lm_flags |= LML_FLG_PLTREL; 274 return (1); 275 } 276 277 /* 278 * Lazy load an object. 279 */ 280 Rt_map * 281 elf_lazy_load(Rt_map *clmp, uint_t ndx, const char *sym) 282 { 283 Rt_map *nlmp, *hlmp; 284 Dyninfo *dip = &DYNINFO(clmp)[ndx]; 285 uint_t flags = 0; 286 Pnode *pnp; 287 const char *name; 288 Lm_list *lml = LIST(clmp); 289 Lm_cntl *lmc; 290 Aliste lmco; 291 292 /* 293 * If this dependency has already been processed, we're done. 294 */ 295 if (((nlmp = (Rt_map *)dip->di_info) != 0) || 296 (dip->di_flags & FLG_DI_PROCESSD)) 297 return (nlmp); 298 299 /* 300 * Determine the initial dependency name, and indicate that this 301 * dependencies processing has initiated. 302 */ 303 name = STRTAB(clmp) + DYN(clmp)[ndx].d_un.d_val; 304 DBG_CALL(Dbg_file_lazyload(clmp, name, sym)); 305 if (lml->lm_flags & LML_FLG_TRC_ENABLE) 306 dip->di_flags |= FLG_DI_PROCESSD; 307 308 if (dip->di_flags & FLG_DI_GROUP) 309 flags |= (FLG_RT_SETGROUP | FLG_RT_HANDLE); 310 311 /* 312 * Expand the requested name if necessary. 313 */ 314 if ((pnp = elf_fix_name(name, clmp, PN_SER_NEEDED)) == 0) 315 return (0); 316 317 /* 318 * Provided the object on the head of the link-map has completed its 319 * relocation, create a new link-map control list for this request. 320 */ 321 hlmp = lml->lm_head; 322 if (FLAGS(hlmp) & FLG_RT_RELOCED) { 323 if ((lmc = alist_append(&(lml->lm_lists), 0, sizeof (Lm_cntl), 324 AL_CNT_LMLISTS)) == 0) { 325 remove_pnode(pnp); 326 return (0); 327 } 328 lmco = (Aliste)((char *)lmc - (char *)lml->lm_lists); 329 } else { 330 lmc = 0; 331 lmco = ALO_DATA; 332 } 333 334 /* 335 * Load the associated object. 336 */ 337 dip->di_info = nlmp = 338 load_one(lml, lmco, pnp, clmp, MODE(clmp), flags, 0); 339 340 /* 341 * Remove any expanded pathname infrastructure. Reduce the pending lazy 342 * dependency count of the caller, together with the link-map lists 343 * count of objects that still have lazy dependencies pending. 344 */ 345 remove_pnode(pnp); 346 if (--LAZY(clmp) == 0) 347 LIST(clmp)->lm_lazy--; 348 349 /* 350 * Finish processing the objects associated with this request, and 351 * create an association between the caller and this dependency. 352 */ 353 if (nlmp && (((analyze_lmc(lml, lmco, nlmp) == 0)) || 354 (relocate_lmc(lml, lmco, clmp, nlmp) == 0) || 355 (bind_one(clmp, nlmp, BND_NEEDED) == 0))) 356 dip->di_info = nlmp = 0; 357 358 /* 359 * If this lazyload has failed, and we've created a new link-map 360 * control list to which this request has added objects, then remove 361 * all the objects that have been associated to this request. 362 */ 363 if ((nlmp == 0) && lmc && lmc->lc_head) 364 remove_lmc(lml, clmp, lmc, lmco, name); 365 366 /* 367 * Finally, remove any link-map control list that was created. 368 */ 369 if (lmc) 370 remove_cntl(lml, lmco); 371 372 return (nlmp); 373 } 374 375 /* 376 * Return the entry point of the ELF executable. 377 */ 378 static ulong_t 379 elf_entry_pt(void) 380 { 381 return (ENTRY(lml_main.lm_head)); 382 } 383 384 /* 385 * Unmap a given ELF shared object from the address space. 386 */ 387 static void 388 elf_unmap_so(Rt_map *lmp) 389 { 390 caddr_t addr; 391 size_t size; 392 Mmap *mmaps; 393 394 /* 395 * If this link map represents a relocatable object concatenation, then 396 * the image was simply generated in allocated memory. Free the memory. 397 * 398 * Note: the memory was originally allocated in the libelf:_elf_outmap 399 * routine and would normally have been free'd in elf_outsync(), but 400 * because we 'interpose' on that routine the memory wasn't free'd at 401 * that time. 402 */ 403 if (FLAGS(lmp) & FLG_RT_IMGALLOC) { 404 free((void *)ADDR(lmp)); 405 return; 406 } 407 408 /* 409 * If padding was enabled via rtld_db, then we have at least one page 410 * in front of the image - and possibly a trailing page. 411 * Unmap the front page first: 412 */ 413 if (PADSTART(lmp) != ADDR(lmp)) { 414 addr = (caddr_t)M_PTRUNC(PADSTART(lmp)); 415 size = ADDR(lmp) - (ulong_t)addr; 416 (void) munmap(addr, size); 417 } 418 419 /* 420 * Unmap any trailing padding. 421 */ 422 if (M_PROUND((PADSTART(lmp) + PADIMLEN(lmp))) > 423 M_PROUND(ADDR(lmp) + MSIZE(lmp))) { 424 addr = (caddr_t)M_PROUND(ADDR(lmp) + MSIZE(lmp)); 425 size = M_PROUND(PADSTART(lmp) + PADIMLEN(lmp)) - (ulong_t)addr; 426 (void) munmap(addr, size); 427 } 428 429 /* 430 * Unmmap all mapped segments. 431 */ 432 for (mmaps = MMAPS(lmp); mmaps->m_vaddr; mmaps++) 433 (void) munmap(mmaps->m_vaddr, mmaps->m_msize); 434 } 435 436 /* 437 * Determine if a dependency requires a particular version and if so verify 438 * that the version exists in the dependency. 439 */ 440 static int 441 elf_verify_vers(const char *name, Rt_map *clmp, Rt_map *nlmp) 442 { 443 Verneed *vnd = VERNEED(clmp); 444 int _num, num = VERNEEDNUM(clmp); 445 char *cstrs = (char *)STRTAB(clmp); 446 Lm_list *lml = LIST(clmp); 447 448 /* 449 * Traverse the callers version needed information and determine if any 450 * specific versions are required from the dependency. 451 */ 452 DBG_CALL(Dbg_ver_need_title(LIST(clmp), NAME(clmp))); 453 for (_num = 1; _num <= num; _num++, 454 vnd = (Verneed *)((Xword)vnd + vnd->vn_next)) { 455 Half cnt = vnd->vn_cnt; 456 Vernaux *vnap; 457 char *nstrs, *need; 458 459 /* 460 * Determine if a needed entry matches this dependency. 461 */ 462 need = (char *)(cstrs + vnd->vn_file); 463 if (strcmp(name, need) != 0) 464 continue; 465 466 if ((lml->lm_flags & LML_FLG_TRC_VERBOSE) && 467 ((FLAGS1(clmp) & FL1_RT_LDDSTUB) == 0)) 468 (void) printf(MSG_INTL(MSG_LDD_VER_FIND), name); 469 470 /* 471 * Validate that each version required actually exists in the 472 * dependency. 473 */ 474 nstrs = (char *)STRTAB(nlmp); 475 476 for (vnap = (Vernaux *)((Xword)vnd + vnd->vn_aux); cnt; 477 cnt--, vnap = (Vernaux *)((Xword)vnap + vnap->vna_next)) { 478 char *version, *define; 479 Verdef *vdf = VERDEF(nlmp); 480 ulong_t _num, num = VERDEFNUM(nlmp); 481 int found = 0; 482 483 version = (char *)(cstrs + vnap->vna_name); 484 DBG_CALL(Dbg_ver_need_entry(lml, 0, need, version)); 485 486 for (_num = 1; _num <= num; _num++, 487 vdf = (Verdef *)((Xword)vdf + vdf->vd_next)) { 488 Verdaux *vdap; 489 490 if (vnap->vna_hash != vdf->vd_hash) 491 continue; 492 493 vdap = (Verdaux *)((Xword)vdf + vdf->vd_aux); 494 define = (char *)(nstrs + vdap->vda_name); 495 if (strcmp(version, define) != 0) 496 continue; 497 498 found++; 499 break; 500 } 501 502 /* 503 * If we're being traced print out any matched version 504 * when the verbose (-v) option is in effect. Always 505 * print any unmatched versions. 506 */ 507 if (lml->lm_flags & LML_FLG_TRC_ENABLE) { 508 /* BEGIN CSTYLED */ 509 if (found) { 510 if (!(lml->lm_flags & LML_FLG_TRC_VERBOSE)) 511 continue; 512 513 (void) printf(MSG_ORIG(MSG_LDD_VER_FOUND), 514 need, version, NAME(nlmp)); 515 } else { 516 if (rtld_flags & RT_FL_SILENCERR) 517 continue; 518 519 (void) printf(MSG_INTL(MSG_LDD_VER_NFOUND), 520 need, version); 521 } 522 /* END CSTYLED */ 523 continue; 524 } 525 526 /* 527 * If the version hasn't been found then this is a 528 * candidate for a fatal error condition. Weak 529 * version definition requirements are silently 530 * ignored. Also, if the image inspected for a version 531 * definition has no versioning recorded at all then 532 * silently ignore this (this provides better backward 533 * compatibility to old images created prior to 534 * versioning being available). Both of these skipped 535 * diagnostics are available under tracing (see above). 536 */ 537 if ((found == 0) && (num != 0) && 538 (!(vnap->vna_flags & VER_FLG_WEAK))) { 539 eprintf(lml, ERR_FATAL, 540 MSG_INTL(MSG_VER_NFOUND), need, version, 541 NAME(clmp)); 542 return (0); 543 } 544 } 545 } 546 DBG_CALL(Dbg_util_nl(lml, DBG_NL_STD)); 547 return (1); 548 } 549 550 /* 551 * Search through the dynamic section for DT_NEEDED entries and perform one 552 * of two functions. If only the first argument is specified then load the 553 * defined shared object, otherwise add the link map representing the defined 554 * link map the the dlopen list. 555 */ 556 static int 557 elf_needed(Lm_list *lml, Aliste lmco, Rt_map *clmp) 558 { 559 Dyn *dyn; 560 ulong_t ndx = 0; 561 uint_t lazy = 0, flags = 0; 562 Word lmflags = lml->lm_flags; 563 Word lmtflags = lml->lm_tflags; 564 565 /* 566 * Process each shared object on needed list. 567 */ 568 if (DYN(clmp) == 0) 569 return (1); 570 571 for (dyn = (Dyn *)DYN(clmp); dyn->d_tag != DT_NULL; dyn++, ndx++) { 572 Dyninfo *dip = &DYNINFO(clmp)[ndx]; 573 Rt_map *nlmp = 0; 574 char *name; 575 int silent = 0; 576 Pnode *pnp; 577 578 switch (dyn->d_tag) { 579 case DT_POSFLAG_1: 580 if ((dyn->d_un.d_val & DF_P1_LAZYLOAD) && 581 !(lmtflags & LML_TFLG_NOLAZYLD)) 582 lazy = 1; 583 if (dyn->d_un.d_val & DF_P1_GROUPPERM) 584 flags = (FLG_RT_SETGROUP | FLG_RT_HANDLE); 585 continue; 586 case DT_NEEDED: 587 case DT_USED: 588 dip->di_flags |= FLG_DI_NEEDED; 589 if (flags) 590 dip->di_flags |= FLG_DI_GROUP; 591 592 name = (char *)STRTAB(clmp) + dyn->d_un.d_val; 593 594 /* 595 * NOTE, libc.so.1 can't be lazy loaded. Although a 596 * lazy position flag won't be produced when a RTLDINFO 597 * .dynamic entry is found (introduced with the UPM in 598 * Solaris 10), it was possible to mark libc for lazy 599 * loading on previous releases. To reduce the overhead 600 * of testing for this occurrence, only carry out this 601 * check for the first object on the link-map list 602 * (there aren't many applications built without libc). 603 */ 604 if (lazy && (lml->lm_head == clmp) && 605 (strcmp(name, MSG_ORIG(MSG_FIL_LIBC)) == 0)) 606 lazy = 0; 607 608 /* 609 * Don't bring in lazy loaded objects yet unless we've 610 * been asked to attempt to load all available objects 611 * (crle(1) sets LD_FLAGS=loadavail). Even under 612 * RTLD_NOW we don't process this - RTLD_NOW will cause 613 * relocation processing which in turn might trigger 614 * lazy loading, but its possible that the object has a 615 * lazy loaded file with no bindings (i.e., it should 616 * never have been a dependency in the first place). 617 */ 618 if (lazy) { 619 if ((lmflags & LML_FLG_LOADAVAIL) == 0) { 620 LAZY(clmp)++; 621 lazy = flags = 0; 622 continue; 623 } 624 625 /* 626 * Silence any error messages - see description 627 * under elf_lookup_filtee(). 628 */ 629 if ((rtld_flags & RT_FL_SILENCERR) == 0) { 630 rtld_flags |= RT_FL_SILENCERR; 631 silent = 1; 632 } 633 } 634 break; 635 case DT_AUXILIARY: 636 dip->di_flags |= FLG_DI_AUXFLTR; 637 lazy = flags = 0; 638 continue; 639 case DT_SUNW_AUXILIARY: 640 dip->di_flags |= (FLG_DI_AUXFLTR | FLG_DI_SYMFLTR); 641 lazy = flags = 0; 642 continue; 643 case DT_FILTER: 644 dip->di_flags |= FLG_DI_STDFLTR; 645 lazy = flags = 0; 646 continue; 647 case DT_SUNW_FILTER: 648 dip->di_flags |= (FLG_DI_STDFLTR | FLG_DI_SYMFLTR); 649 lazy = flags = 0; 650 continue; 651 default: 652 lazy = flags = 0; 653 continue; 654 } 655 656 DBG_CALL(Dbg_file_needed(clmp, name)); 657 if (lml->lm_flags & LML_FLG_TRC_ENABLE) 658 dip->di_flags |= FLG_DI_PROCESSD; 659 660 /* 661 * Establish the objects name, load it and establish a binding 662 * with the caller. 663 */ 664 if (((pnp = elf_fix_name(name, clmp, PN_SER_NEEDED)) == 0) || 665 ((nlmp = load_one(lml, lmco, pnp, clmp, MODE(clmp), 666 flags, 0)) == 0) || (bind_one(clmp, nlmp, BND_NEEDED) == 0)) 667 nlmp = 0; 668 669 /* 670 * Clean up any infrastructure, including the removal of the 671 * error suppression state, if it had been previously set in 672 * this routine. 673 */ 674 if (pnp) 675 remove_pnode(pnp); 676 if (silent) 677 rtld_flags &= ~RT_FL_SILENCERR; 678 lazy = flags = 0; 679 if ((dip->di_info = (void *)nlmp) == 0) { 680 /* 681 * If the object could not be mapped, continue if error 682 * suppression is established or we're here with ldd(1). 683 */ 684 if ((MODE(clmp) & RTLD_CONFGEN) || (lmflags & 685 (LML_FLG_LOADAVAIL | LML_FLG_TRC_ENABLE))) 686 continue; 687 else 688 return (0); 689 } 690 } 691 692 if (LAZY(clmp)) 693 lml->lm_lazy++; 694 695 return (1); 696 } 697 698 static int 699 elf_map_check(Lm_list *lml, const char *name, caddr_t vaddr, Off size) 700 { 701 prmap_t *maps, *_maps; 702 int pfd, num, _num; 703 caddr_t eaddr = vaddr + size; 704 int err; 705 706 /* 707 * If memory reservations have been established for alternative objects 708 * determine if this object falls within the reservation, if it does no 709 * further checking is required. 710 */ 711 if (rtld_flags & RT_FL_MEMRESV) { 712 Rtc_head *head = (Rtc_head *)config->c_bgn; 713 714 if ((vaddr >= (caddr_t)(uintptr_t)head->ch_resbgn) && 715 (eaddr <= (caddr_t)(uintptr_t)head->ch_resend)) 716 return (0); 717 } 718 719 /* 720 * Determine the mappings presently in use by this process. 721 */ 722 if ((pfd = pr_open(lml)) == FD_UNAVAIL) 723 return (1); 724 725 if (ioctl(pfd, PIOCNMAP, (void *)&num) == -1) { 726 err = errno; 727 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_SYS_PROC), name, 728 strerror(err)); 729 return (1); 730 } 731 732 if ((maps = malloc((num + 1) * sizeof (prmap_t))) == 0) 733 return (1); 734 735 if (ioctl(pfd, PIOCMAP, (void *)maps) == -1) { 736 err = errno; 737 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_SYS_PROC), name, 738 strerror(err)); 739 free(maps); 740 return (1); 741 } 742 743 /* 744 * Determine if the supplied address clashes with any of the present 745 * process mappings. 746 */ 747 for (_num = 0, _maps = maps; _num < num; _num++, _maps++) { 748 caddr_t _eaddr = _maps->pr_vaddr + _maps->pr_size; 749 Rt_map *lmp; 750 const char *str; 751 752 if ((eaddr < _maps->pr_vaddr) || (vaddr >= _eaddr)) 753 continue; 754 755 /* 756 * We have a memory clash. See if one of the known dynamic 757 * dependency mappings represents this space so as to provide 758 * the user a more meaningful message. 759 */ 760 if ((lmp = _caller(vaddr, 0)) != 0) 761 str = NAME(lmp); 762 else 763 str = MSG_INTL(MSG_STR_UNKNOWN); 764 765 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_GEN_MAPINUSE), name, 766 EC_NATPTR(vaddr), EC_OFF(size), str); 767 return (1); 768 } 769 free(maps); 770 return (0); 771 } 772 773 /* 774 * Obtain a memory reservation. On newer systems, both MAP_ANON and MAP_ALIGN 775 * are used to obtained an aligned reservation from anonymous memory. If 776 * MAP_ANON isn't available, then MAP_ALIGN isn't either, so obtain a standard 777 * reservation using the file as backing. 778 */ 779 static Am_ret 780 elf_map_reserve(Lm_list *lml, const char *name, caddr_t *maddr, Off msize, 781 int mperm, int fd, Xword align) 782 { 783 Am_ret amret; 784 int mflag = MAP_PRIVATE | MAP_NORESERVE; 785 786 #if defined(MAP_ALIGN) 787 if ((rtld_flags2 & RT_FL2_NOMALIGN) == 0) { 788 mflag |= MAP_ALIGN; 789 *maddr = (caddr_t)align; 790 } 791 #endif 792 if ((amret = anon_map(lml, maddr, msize, PROT_NONE, mflag)) == AM_ERROR) 793 return (amret); 794 795 if (amret == AM_OK) 796 return (AM_OK); 797 798 /* 799 * If an anonymous memory request failed (which should only be the 800 * case if it is unsupported on the system we're running on), establish 801 * the initial mapping directly from the file. 802 */ 803 *maddr = 0; 804 if ((*maddr = mmap(*maddr, msize, mperm, MAP_PRIVATE, 805 fd, 0)) == MAP_FAILED) { 806 int err = errno; 807 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_SYS_MMAP), name, 808 strerror(err)); 809 return (AM_ERROR); 810 } 811 return (AM_NOSUP); 812 } 813 814 static void * 815 elf_map_textdata(caddr_t addr, Off flen, int mperm, int phdr_mperm, int mflag, 816 int fd, Off foff) 817 { 818 #if defined(MAP_TEXT) && defined(MAP_INITDATA) 819 static int notd = 0; 820 821 /* 822 * If MAP_TEXT and MAP_INITDATA are available, select the appropriate 823 * flag. 824 */ 825 if (notd == 0) { 826 if ((phdr_mperm & (PROT_WRITE | PROT_EXEC)) == PROT_EXEC) 827 mflag |= MAP_TEXT; 828 else 829 mflag |= MAP_INITDATA; 830 } 831 #endif 832 if (mmap((caddr_t)addr, flen, mperm, mflag, fd, foff) != MAP_FAILED) 833 return (0); 834 835 #if defined(MAP_TEXT) && defined(MAP_INITDATA) 836 if ((notd == 0) && (errno == EINVAL)) { 837 /* 838 * MAP_TEXT and MAP_INITDATA may not be supported on this 839 * platform, try again without. 840 */ 841 notd = 1; 842 mflag &= ~(MAP_TEXT | MAP_INITDATA); 843 844 return (mmap((caddr_t)addr, flen, mperm, mflag, fd, foff)); 845 } 846 #endif 847 return (MAP_FAILED); 848 } 849 850 /* 851 * Map in a file. 852 */ 853 static caddr_t 854 elf_map_it( 855 Lm_list *lml, /* link-map list */ 856 const char *name, /* actual name stored for pathname */ 857 Off fsize, /* total mapping claim of the file */ 858 Ehdr *ehdr, /* ELF header of file */ 859 Phdr *fphdr, /* first loadable Phdr */ 860 Phdr *lphdr, /* last loadable Phdr */ 861 Phdr **rrphdr, /* return first Phdr in reservation */ 862 caddr_t *rraddr, /* return start of reservation */ 863 Off *rrsize, /* return total size of reservation */ 864 int fixed, /* image is resolved to a fixed addr */ 865 int fd, /* images file descriptor */ 866 Xword align, /* image segments maximum alignment */ 867 Mmap *mmaps, /* mmap information array and */ 868 uint_t *mmapcnt) /* mapping count */ 869 { 870 caddr_t raddr; /* reservation address */ 871 Off rsize; /* reservation size */ 872 Phdr *phdr; /* working program header poiner */ 873 caddr_t maddr; /* working mmap address */ 874 caddr_t faddr; /* working file address */ 875 size_t padsize; /* object padding requirement */ 876 size_t padpsize = 0; /* padding size rounded to next page */ 877 size_t padmsize = 0; /* padding size rounded for alignment */ 878 int skipfseg; /* skip mapping first segment */ 879 int mperm; /* segment permissions */ 880 Am_ret amret = AM_NOSUP; 881 882 /* 883 * If padding is required extend both the front and rear of the image. 884 * To insure the image itself is mapped at the correct alignment the 885 * initial padding is rounded up to the nearest page. Once the image is 886 * mapped the excess can be pruned to the nearest page required for the 887 * actual padding itself. 888 */ 889 if ((padsize = r_debug.rtd_objpad) != 0) { 890 padpsize = M_PROUND(padsize); 891 if (fixed) 892 padmsize = padpsize; 893 else 894 padmsize = S_ROUND(padsize, align); 895 } 896 897 /* 898 * Determine the initial permissions used to map in the first segment. 899 * If this segments memsz is greater that its filesz then the difference 900 * must be zeroed. Make sure this segment is writable. 901 */ 902 mperm = 0; 903 if (fphdr->p_flags & PF_R) 904 mperm |= PROT_READ; 905 if (fphdr->p_flags & PF_X) 906 mperm |= PROT_EXEC; 907 if ((fphdr->p_flags & PF_W) || (fphdr->p_memsz > fphdr->p_filesz)) 908 mperm |= PROT_WRITE; 909 910 /* 911 * Determine whether or not to let system reserve address space based on 912 * whether this is a dynamic executable (addresses in object are fixed) 913 * or a shared object (addresses in object are relative to the objects' 914 * base). 915 */ 916 if (fixed) { 917 /* 918 * Determine the reservation address and size, and insure that 919 * this reservation isn't already in use. 920 */ 921 faddr = maddr = (caddr_t)M_PTRUNC((ulong_t)fphdr->p_vaddr); 922 raddr = maddr - padpsize; 923 rsize = fsize + padpsize + padsize; 924 925 if (lml_main.lm_head) { 926 if (elf_map_check(lml, name, raddr, rsize) != 0) 927 return (0); 928 } 929 930 /* 931 * As this is a fixed image, all segments must be individually 932 * mapped. 933 */ 934 skipfseg = 0; 935 936 } else { 937 size_t esize; 938 939 /* 940 * If this isn't a fixed image, reserve enough address space for 941 * the entire image to be mapped. The amount of reservation is 942 * the range between the beginning of the first, and end of the 943 * last loadable segment, together with any padding, plus the 944 * alignment of the first segment. 945 * 946 * The optimal reservation is made as a no-reserve mapping from 947 * anonymous memory. Each segment is then mapped into this 948 * reservation. If the anonymous mapping capability isn't 949 * available, the reservation is obtained from the file itself. 950 * In this case the first segment of the image is mapped as part 951 * of the reservation, thus only the following segments need to 952 * be remapped. 953 */ 954 rsize = fsize + padmsize + padsize; 955 if ((amret = elf_map_reserve(lml, name, &raddr, rsize, mperm, 956 fd, align)) == AM_ERROR) 957 return (0); 958 maddr = raddr + padmsize; 959 faddr = (caddr_t)S_ROUND((Off)maddr, align); 960 961 /* 962 * If this reservation has been obtained from anonymous memory, 963 * then all segments must be individually mapped. Otherwise, 964 * the first segment heads the reservation. 965 */ 966 if (amret == AM_OK) 967 skipfseg = 0; 968 else 969 skipfseg = 1; 970 971 /* 972 * For backward compatibility (where MAP_ALIGN isn't available), 973 * insure the alignment of the reservation is adequate for this 974 * object, and if not remap the object to obtain the correct 975 * alignment. 976 */ 977 if (faddr != maddr) { 978 (void) munmap(raddr, rsize); 979 980 rsize += align; 981 if ((amret = elf_map_reserve(lml, name, &raddr, rsize, 982 mperm, fd, align)) == AM_ERROR) 983 return (0); 984 985 maddr = faddr = (caddr_t)S_ROUND((Off)(raddr + 986 padpsize), align); 987 988 esize = maddr - raddr + padpsize; 989 990 /* 991 * As ths image has been realigned, the first segment 992 * of the file needs to be remapped to its correct 993 * location. 994 */ 995 skipfseg = 0; 996 } else 997 esize = padmsize - padpsize; 998 999 /* 1000 * If this reservation included padding, remove any excess for 1001 * the start of the image (the padding was adjusted to insure 1002 * the image was aligned appropriately). 1003 */ 1004 if (esize) { 1005 (void) munmap(raddr, esize); 1006 raddr += esize; 1007 rsize -= esize; 1008 } 1009 } 1010 1011 /* 1012 * At this point we know the initial location of the image, and its 1013 * size. Pass these back to the caller for inclusion in the link-map 1014 * that will eventually be created. 1015 */ 1016 *rraddr = raddr; 1017 *rrsize = rsize; 1018 1019 /* 1020 * The first loadable segment is now pointed to by maddr. This segment 1021 * will eventually contain the elf header and program headers, so reset 1022 * the program header. Pass this back to the caller for inclusion in 1023 * the link-map so it can be used for later unmapping operations. 1024 */ 1025 /* LINTED */ 1026 *rrphdr = (Phdr *)((char *)maddr + ehdr->e_phoff); 1027 1028 /* 1029 * If padding is required at the front of the image, obtain that now. 1030 * Note, if we've already obtained a reservation from anonymous memory 1031 * then this reservation will already include suitable padding. 1032 * Otherwise this reservation is backed by the file, or in the case of 1033 * a fixed image, doesn't yet exist. Map the padding so that it is 1034 * suitably protected (PROT_NONE), and insure the first segment of the 1035 * file is mapped to its correct location. 1036 */ 1037 if (padsize) { 1038 if (amret == AM_NOSUP) { 1039 if (dz_map(lml, raddr, padpsize, PROT_NONE, 1040 (MAP_PRIVATE | MAP_FIXED | MAP_NORESERVE)) == 1041 MAP_FAILED) 1042 return (0); 1043 1044 skipfseg = 0; 1045 } 1046 rsize -= padpsize; 1047 } 1048 1049 /* 1050 * Map individual segments. For a fixed image, these will each be 1051 * unique mappings. For a reservation these will fill in the 1052 * reservation. 1053 */ 1054 for (phdr = fphdr; phdr <= lphdr; 1055 phdr = (Phdr *)((Off)phdr + ehdr->e_phentsize)) { 1056 caddr_t addr; 1057 Off mlen, flen; 1058 size_t size; 1059 1060 /* 1061 * Skip non-loadable segments or segments that don't occupy 1062 * any memory. 1063 */ 1064 if (((phdr->p_type != PT_LOAD) && 1065 (phdr->p_type != PT_SUNWBSS)) || (phdr->p_memsz == 0)) 1066 continue; 1067 1068 /* 1069 * Establish this segments address relative to our base. 1070 */ 1071 addr = (caddr_t)M_PTRUNC((ulong_t)(phdr->p_vaddr + 1072 (fixed ? 0 : faddr))); 1073 1074 /* 1075 * Determine the mapping protection from the segment attributes. 1076 * Also determine the etext address from the last loadable 1077 * segment which has permissions but no write access. 1078 */ 1079 mperm = 0; 1080 if (phdr->p_flags) { 1081 if (phdr->p_flags & PF_R) 1082 mperm |= PROT_READ; 1083 if (phdr->p_flags & PF_X) 1084 mperm |= PROT_EXEC; 1085 if (phdr->p_flags & PF_W) 1086 mperm |= PROT_WRITE; 1087 else 1088 fmap->fm_etext = phdr->p_vaddr + phdr->p_memsz + 1089 (ulong_t)(fixed ? 0 : faddr); 1090 } 1091 1092 /* 1093 * Determine the type of mapping required. 1094 */ 1095 if (phdr->p_type == PT_SUNWBSS) { 1096 /* 1097 * Potentially, we can defer the loading of any SUNWBSS 1098 * segment, depending on whether the symbols it provides 1099 * have been bound to. In this manner, large segments 1100 * that are interposed upon between shared libraries 1101 * may not require mapping. Note, that the mapping 1102 * information is recorded in our mapping descriptor at 1103 * this time. 1104 */ 1105 mlen = phdr->p_memsz; 1106 flen = 0; 1107 1108 } else if ((phdr->p_filesz == 0) && (phdr->p_flags == 0)) { 1109 /* 1110 * If this segment has no backing file and no flags 1111 * specified, then it defines a reservation. At this 1112 * point all standard loadable segments will have been 1113 * processed. The segment reservation is mapped 1114 * directly from /dev/null. 1115 */ 1116 if (nu_map(lml, (caddr_t)addr, phdr->p_memsz, PROT_NONE, 1117 MAP_FIXED | MAP_PRIVATE) == MAP_FAILED) 1118 return (0); 1119 1120 mlen = phdr->p_memsz; 1121 flen = 0; 1122 1123 } else if (phdr->p_filesz == 0) { 1124 /* 1125 * If this segment has no backing file then it defines a 1126 * nobits segment and is mapped directly from /dev/zero. 1127 */ 1128 if (dz_map(lml, (caddr_t)addr, phdr->p_memsz, mperm, 1129 MAP_FIXED | MAP_PRIVATE) == MAP_FAILED) 1130 return (0); 1131 1132 mlen = phdr->p_memsz; 1133 flen = 0; 1134 1135 } else { 1136 Off foff; 1137 1138 /* 1139 * This mapping originates from the file. Determine the 1140 * file offset to which the mapping will be directed 1141 * (must be aligned) and how much to map (might be more 1142 * than the file in the case of .bss). 1143 */ 1144 foff = M_PTRUNC((ulong_t)phdr->p_offset); 1145 mlen = phdr->p_memsz + (phdr->p_offset - foff); 1146 flen = phdr->p_filesz + (phdr->p_offset - foff); 1147 1148 /* 1149 * If this is a non-fixed, non-anonymous mapping, and no 1150 * padding is involved, then the first loadable segment 1151 * is already part of the initial reservation. In this 1152 * case there is no need to remap this segment. 1153 */ 1154 if ((skipfseg == 0) || (phdr != fphdr)) { 1155 int phdr_mperm = mperm; 1156 /* 1157 * If this segments memsz is greater that its 1158 * filesz then the difference must be zeroed. 1159 * Make sure this segment is writable. 1160 */ 1161 if (phdr->p_memsz > phdr->p_filesz) 1162 mperm |= PROT_WRITE; 1163 1164 if (elf_map_textdata((caddr_t)addr, flen, 1165 mperm, phdr_mperm, 1166 (MAP_FIXED | MAP_PRIVATE), fd, foff) == 1167 MAP_FAILED) { 1168 int err = errno; 1169 eprintf(lml, ERR_FATAL, 1170 MSG_INTL(MSG_SYS_MMAP), name, 1171 strerror(err)); 1172 return (0); 1173 } 1174 } 1175 1176 /* 1177 * If the memory occupancy of the segment overflows the 1178 * definition in the file, we need to "zero out" the end 1179 * of the mapping we've established, and if necessary, 1180 * map some more space from /dev/zero. Note, zero'ed 1181 * memory must end on a double word boundary to satisfy 1182 * zero(). 1183 */ 1184 if (phdr->p_memsz > phdr->p_filesz) { 1185 caddr_t zaddr; 1186 size_t zlen, zplen; 1187 Off fend; 1188 1189 foff = (Off)(phdr->p_vaddr + phdr->p_filesz + 1190 (fixed ? 0 : faddr)); 1191 zaddr = (caddr_t)M_PROUND(foff); 1192 zplen = (size_t)(zaddr - foff); 1193 1194 fend = (Off)S_DROUND((size_t)(phdr->p_vaddr + 1195 phdr->p_memsz + (fixed ? 0 : faddr))); 1196 zlen = (size_t)(fend - foff); 1197 1198 /* 1199 * Determine whether the number of bytes that 1200 * must be zero'ed overflow to the next page. 1201 * If not, simply clear the exact bytes 1202 * (filesz to memsz) from this page. Otherwise, 1203 * clear the remaining bytes of this page, and 1204 * map an following pages from /dev/zero. 1205 */ 1206 if (zlen < zplen) 1207 zero((caddr_t)foff, (long)zlen); 1208 else { 1209 zero((caddr_t)foff, (long)zplen); 1210 1211 if ((zlen = (fend - (Off)zaddr)) > 0) { 1212 if (dz_map(lml, zaddr, zlen, 1213 mperm, 1214 MAP_FIXED | MAP_PRIVATE) == 1215 MAP_FAILED) 1216 return (0); 1217 } 1218 } 1219 } 1220 } 1221 1222 /* 1223 * Unmap anything from the last mapping address to this one and 1224 * update the mapping claim pointer. 1225 */ 1226 if ((fixed == 0) && ((size = addr - maddr) != 0)) { 1227 (void) munmap(maddr, size); 1228 rsize -= size; 1229 } 1230 1231 /* 1232 * Retain this segments mapping information. 1233 */ 1234 mmaps[*mmapcnt].m_vaddr = addr; 1235 mmaps[*mmapcnt].m_msize = mlen; 1236 mmaps[*mmapcnt].m_fsize = flen; 1237 mmaps[*mmapcnt].m_perm = mperm; 1238 (*mmapcnt)++; 1239 1240 maddr = addr + M_PROUND(mlen); 1241 rsize -= M_PROUND(mlen); 1242 } 1243 1244 /* 1245 * If padding is required at the end of the image, obtain that now. 1246 * Note, if we've already obtained a reservation from anonymous memory 1247 * then this reservation will already include suitable padding. 1248 */ 1249 if (padsize) { 1250 if (amret == AM_NOSUP) { 1251 /* 1252 * maddr is currently page aligned from the last segment 1253 * mapping. 1254 */ 1255 if (dz_map(lml, maddr, padsize, PROT_NONE, 1256 (MAP_PRIVATE | MAP_FIXED | MAP_NORESERVE)) == 1257 MAP_FAILED) 1258 return (0); 1259 } 1260 maddr += padsize; 1261 rsize -= padsize; 1262 } 1263 1264 /* 1265 * Unmap any final reservation. 1266 */ 1267 if ((fixed == 0) && (rsize != 0)) 1268 (void) munmap(maddr, rsize); 1269 1270 return (faddr); 1271 } 1272 1273 /* 1274 * A null symbol interpretor. Used if a filter has no associated filtees. 1275 */ 1276 /* ARGSUSED0 */ 1277 static Sym * 1278 elf_null_find_sym(Slookup *slp, Rt_map **dlmp, uint_t *binfo) 1279 { 1280 return ((Sym *)0); 1281 } 1282 1283 /* 1284 * Disable filtee use. 1285 */ 1286 static void 1287 elf_disable_filtee(Rt_map *lmp, Dyninfo *dip) 1288 { 1289 dip->di_info = 0; 1290 1291 if ((dip->di_flags & FLG_DI_SYMFLTR) == 0) { 1292 /* 1293 * If this is an object filter, free the filtee's duplication. 1294 */ 1295 if (OBJFLTRNDX(lmp) != FLTR_DISABLED) { 1296 free(REFNAME(lmp)); 1297 REFNAME(lmp) = (char *)0; 1298 OBJFLTRNDX(lmp) = FLTR_DISABLED; 1299 1300 /* 1301 * Indicate that this filtee is no longer available. 1302 */ 1303 if (dip->di_flags & FLG_DI_STDFLTR) 1304 SYMINTP(lmp) = elf_null_find_sym; 1305 1306 } 1307 } else if (dip->di_flags & FLG_DI_STDFLTR) { 1308 /* 1309 * Indicate that this standard filtee is no longer available. 1310 */ 1311 if (SYMSFLTRCNT(lmp)) 1312 SYMSFLTRCNT(lmp)--; 1313 } else { 1314 /* 1315 * Indicate that this auxiliary filtee is no longer available. 1316 */ 1317 if (SYMAFLTRCNT(lmp)) 1318 SYMAFLTRCNT(lmp)--; 1319 } 1320 dip->di_flags &= ~MSK_DI_FILTER; 1321 } 1322 1323 /* 1324 * Find symbol interpreter - filters. 1325 * This function is called when the symbols from a shared object should 1326 * be resolved from the shared objects filtees instead of from within itself. 1327 * 1328 * A symbol name of 0 is used to trigger filtee loading. 1329 */ 1330 static Sym * 1331 _elf_lookup_filtee(Slookup *slp, Rt_map **dlmp, uint_t *binfo, uint_t ndx) 1332 { 1333 const char *name = slp->sl_name, *filtees; 1334 Rt_map *clmp = slp->sl_cmap; 1335 Rt_map *ilmp = slp->sl_imap; 1336 Pnode *pnp, **pnpp; 1337 int any; 1338 Dyninfo *dip = &DYNINFO(ilmp)[ndx]; 1339 Lm_list *lml = LIST(ilmp); 1340 1341 /* 1342 * Indicate that the filter has been used. If a binding already exists 1343 * to the caller, indicate that this object is referenced. This insures 1344 * we don't generate false unreferenced diagnostics from ldd -u/U or 1345 * debugging. Don't create a binding regardless, as this filter may 1346 * have been dlopen()'ed. 1347 */ 1348 if (name && (ilmp != clmp)) { 1349 Word tracing = (LIST(clmp)->lm_flags & 1350 (LML_FLG_TRC_UNREF | LML_FLG_TRC_UNUSED)); 1351 1352 if (tracing || DBG_ENABLED) { 1353 Bnd_desc ** bdpp; 1354 Aliste off; 1355 1356 FLAGS1(ilmp) |= FL1_RT_USED; 1357 1358 if ((tracing & LML_FLG_TRC_UNREF) || DBG_ENABLED) { 1359 for (ALIST_TRAVERSE(CALLERS(ilmp), off, bdpp)) { 1360 Bnd_desc * bdp = *bdpp; 1361 1362 if (bdp->b_caller == clmp) { 1363 bdp->b_flags |= BND_REFER; 1364 break; 1365 } 1366 } 1367 } 1368 } 1369 } 1370 1371 /* 1372 * If this is the first call to process this filter, establish the 1373 * filtee list. If a configuration file exists, determine if any 1374 * filtee associations for this filter, and its filtee reference, are 1375 * defined. Otherwise, process the filtee reference. Any token 1376 * expansion is also completed at this point (i.e., $PLATFORM). 1377 */ 1378 filtees = (char *)STRTAB(ilmp) + DYN(ilmp)[ndx].d_un.d_val; 1379 if (dip->di_info == 0) { 1380 if (rtld_flags2 & RT_FL2_FLTCFG) 1381 dip->di_info = elf_config_flt(lml, PATHNAME(ilmp), 1382 filtees); 1383 1384 if (dip->di_info == 0) { 1385 DBG_CALL(Dbg_file_filter(lml, NAME(ilmp), filtees, 0)); 1386 if ((lml->lm_flags & 1387 (LML_FLG_TRC_VERBOSE | LML_FLG_TRC_SEARCH)) && 1388 ((FLAGS1(ilmp) & FL1_RT_LDDSTUB) == 0)) 1389 (void) printf(MSG_INTL(MSG_LDD_FIL_FILTER), 1390 NAME(ilmp), filtees); 1391 1392 if ((dip->di_info = (void *)expand_paths(ilmp, 1393 filtees, PN_SER_FILTEE, 0)) == 0) { 1394 elf_disable_filtee(ilmp, dip); 1395 return ((Sym *)0); 1396 } 1397 } 1398 } 1399 1400 /* 1401 * Traverse the filtee list, dlopen()'ing any objects specified and 1402 * using their group handle to lookup the symbol. 1403 */ 1404 for (any = 0, pnpp = (Pnode **)&(dip->di_info), pnp = *pnpp; pnp; 1405 pnpp = &pnp->p_next, pnp = *pnpp) { 1406 int mode; 1407 Grp_hdl *ghp; 1408 Rt_map *nlmp = 0; 1409 1410 if (pnp->p_len == 0) 1411 continue; 1412 1413 /* 1414 * Establish the mode of the filtee from the filter. As filtees 1415 * are loaded via a dlopen(), make sure that RTLD_GROUP is set 1416 * and the filtees aren't global. It would be nice to have 1417 * RTLD_FIRST used here also, but as filters got out long before 1418 * RTLD_FIRST was introduced it's a little too late now. 1419 */ 1420 mode = MODE(ilmp) | RTLD_GROUP; 1421 mode &= ~RTLD_GLOBAL; 1422 1423 /* 1424 * Insure that any auxiliary filter can locate symbols from its 1425 * caller. 1426 */ 1427 if (dip->di_flags & FLG_DI_AUXFLTR) 1428 mode |= RTLD_PARENT; 1429 1430 /* 1431 * Process any hardware capability directory. Establish a new 1432 * link-map control list from which to analyze any newly added 1433 * objects. 1434 */ 1435 if ((pnp->p_info == 0) && (pnp->p_orig & PN_TKN_HWCAP)) { 1436 Lm_cntl *lmc; 1437 Aliste lmco; 1438 1439 if (FLAGS(lml->lm_head) & FLG_RT_RELOCED) { 1440 if ((lmc = alist_append(&(lml->lm_lists), 0, 1441 sizeof (Lm_cntl), AL_CNT_LMLISTS)) == 0) 1442 return ((Sym *)0); 1443 lmco = (Aliste)((char *)lmc - 1444 (char *)lml->lm_lists); 1445 } else { 1446 lmc = 0; 1447 lmco = ALO_DATA; 1448 } 1449 1450 pnp = hwcap_filtees(pnpp, lmco, lmc, dip, ilmp, filtees, 1451 mode, (FLG_RT_HANDLE | FLG_RT_HWCAP)); 1452 1453 /* 1454 * Now that any hardware capability objects have been 1455 * processed, remove any link-map control list. 1456 */ 1457 if (lmc) 1458 remove_cntl(lml, lmco); 1459 } 1460 1461 if (pnp->p_len == 0) 1462 continue; 1463 1464 /* 1465 * Process an individual filtee. 1466 */ 1467 if (pnp->p_info == 0) { 1468 const char *filtee = pnp->p_name; 1469 int audit = 0; 1470 1471 DBG_CALL(Dbg_file_filtee(lml, NAME(ilmp), filtee, 0)); 1472 1473 ghp = 0; 1474 1475 /* 1476 * Determine if the reference link map is already 1477 * loaded. As an optimization compare the filtee with 1478 * our interpretor. The most common filter is 1479 * libdl.so.1, which is a filter on ld.so.1. 1480 */ 1481 #if defined(_ELF64) 1482 if (strcmp(filtee, MSG_ORIG(MSG_PTH_RTLD_64)) == 0) { 1483 #else 1484 if (strcmp(filtee, MSG_ORIG(MSG_PTH_RTLD)) == 0) { 1485 #endif 1486 /* 1487 * Create an association between ld.so.1 and 1488 * the filter. 1489 */ 1490 nlmp = lml_rtld.lm_head; 1491 if ((ghp = hdl_create(&lml_rtld, nlmp, ilmp, 1492 (GPH_LDSO | GPH_FIRST | GPH_FILTEE))) == 0) 1493 nlmp = 0; 1494 1495 /* 1496 * Establish the filter handle to prevent any 1497 * recursion. 1498 */ 1499 if (nlmp && ghp) 1500 pnp->p_info = (void *)ghp; 1501 1502 /* 1503 * Audit the filter/filtee established. Ignore 1504 * any return from the auditor, as we can't 1505 * allow ignore filtering to ld.so.1, otherwise 1506 * nothing is going to work. 1507 */ 1508 if (nlmp && ((lml->lm_tflags | FLAGS1(ilmp)) & 1509 LML_TFLG_AUD_OBJFILTER)) 1510 (void) audit_objfilter(ilmp, filtees, 1511 nlmp, 0); 1512 1513 } else { 1514 Rej_desc rej = { 0 }; 1515 Lm_cntl *lmc; 1516 Aliste lmco; 1517 1518 /* 1519 * Establish a new link-map control list from 1520 * which to analyze any newly added objects. 1521 */ 1522 if (FLAGS(lml->lm_head) & FLG_RT_RELOCED) { 1523 if ((lmc = 1524 alist_append(&(lml->lm_lists), 0, 1525 sizeof (Lm_cntl), 1526 AL_CNT_LMLISTS)) == 0) 1527 return ((Sym *)0); 1528 lmco = (Aliste)((char *)lmc - 1529 (char *)lml->lm_lists); 1530 } else { 1531 lmc = 0; 1532 lmco = ALO_DATA; 1533 } 1534 1535 /* 1536 * Load the filtee. Note, an auditor can 1537 * provide an alternative name. 1538 */ 1539 if ((nlmp = load_path(lml, lmco, &(pnp->p_name), 1540 ilmp, mode, FLG_RT_HANDLE, &ghp, 0, 1541 &rej)) == 0) { 1542 file_notfound(LIST(ilmp), filtee, ilmp, 1543 FLG_RT_HANDLE, &rej); 1544 remove_rej(&rej); 1545 } 1546 filtee = pnp->p_name; 1547 1548 /* 1549 * Establish the filter handle to prevent any 1550 * recursion. 1551 */ 1552 if (nlmp && ghp) { 1553 ghp->gh_flags |= GPH_FILTEE; 1554 pnp->p_info = (void *)ghp; 1555 } 1556 1557 /* 1558 * Audit the filter/filtee established. A 1559 * return of 0 indicates the auditor wishes to 1560 * ignore this filtee. 1561 */ 1562 if (nlmp && ((lml->lm_tflags | FLAGS1(ilmp)) & 1563 LML_TFLG_AUD_OBJFILTER)) { 1564 if (audit_objfilter(ilmp, filtees, 1565 nlmp, 0) == 0) { 1566 audit = 1; 1567 nlmp = 0; 1568 } 1569 } 1570 1571 /* 1572 * Finish processing the objects associated with 1573 * this request. Create an association between 1574 * this object and the originating filter to 1575 * provide sufficient information to tear down 1576 * this filtee if necessary. 1577 */ 1578 if (nlmp && ghp && 1579 ((analyze_lmc(lml, lmco, nlmp) == 0) || 1580 (relocate_lmc(lml, lmco, ilmp, nlmp) == 0))) 1581 nlmp = 0; 1582 1583 /* 1584 * If the filtee has been successfully 1585 * processed, then create an association 1586 * between the filter and filtee. This 1587 * association provides sufficient information 1588 * to tear down the filter and filtee if 1589 * necessary. 1590 */ 1591 DBG_CALL(Dbg_file_hdl_title(DBG_DEP_ADD)); 1592 if (nlmp && ghp && 1593 (hdl_add(ghp, ilmp, GPD_FILTER) == 0)) 1594 nlmp = 0; 1595 1596 /* 1597 * If this filtee loading has failed, and we've 1598 * created a new link-map control list to which 1599 * this request has added objects, then remove 1600 * all the objects that have been associated to 1601 * this request. 1602 */ 1603 if ((nlmp == 0) && lmc && lmc->lc_head) 1604 remove_lmc(lml, clmp, lmc, lmco, name); 1605 1606 /* 1607 * Remove any link-map control list that was 1608 * created. 1609 */ 1610 if (lmc) 1611 remove_cntl(lml, lmco); 1612 } 1613 1614 /* 1615 * Generate a diagnostic if the filtee couldn't be 1616 * loaded, null out the pnode entry, and continue 1617 * the search. Otherwise, retain this group handle 1618 * for future symbol searches. 1619 */ 1620 if (nlmp == 0) { 1621 DBG_CALL(Dbg_file_filtee(lml, 0, filtee, 1622 audit)); 1623 1624 pnp->p_info = 0; 1625 pnp->p_len = 0; 1626 continue; 1627 } 1628 } 1629 1630 ghp = (Grp_hdl *)pnp->p_info; 1631 1632 /* 1633 * If we're just here to trigger filtee loading skip the symbol 1634 * lookup so we'll continue looking for additional filtees. 1635 */ 1636 if (name) { 1637 Grp_desc *gdp; 1638 Sym *sym = 0; 1639 Aliste off; 1640 Slookup sl = *slp; 1641 1642 sl.sl_flags |= LKUP_FIRST; 1643 any++; 1644 1645 /* 1646 * Look for the symbol in the handles dependencies. 1647 */ 1648 for (ALIST_TRAVERSE(ghp->gh_depends, off, gdp)) { 1649 if ((gdp->gd_flags & GPD_DLSYM) == 0) 1650 continue; 1651 1652 /* 1653 * If our parent is a dependency don't look at 1654 * it (otherwise we are in a recursive loop). 1655 * This situation can occur with auxiliary 1656 * filters if the filtee has a dependency on the 1657 * filter. This dependency isn't necessary as 1658 * auxiliary filters are opened RTLD_PARENT, but 1659 * users may still unknowingly add an explicit 1660 * dependency to the parent. 1661 */ 1662 if ((sl.sl_imap = gdp->gd_depend) == ilmp) 1663 continue; 1664 1665 if (((sym = SYMINTP(sl.sl_imap)(&sl, dlmp, 1666 binfo)) != 0) || 1667 (ghp->gh_flags & GPH_FIRST)) 1668 break; 1669 } 1670 1671 /* 1672 * If a symbol has been found, indicate the binding 1673 * and return the symbol. 1674 */ 1675 if (sym) { 1676 *binfo |= DBG_BINFO_FILTEE; 1677 return (sym); 1678 } 1679 } 1680 1681 /* 1682 * If this object is tagged to terminate filtee processing we're 1683 * done. 1684 */ 1685 if (FLAGS1(ghp->gh_ownlmp) & FL1_RT_ENDFILTE) 1686 break; 1687 } 1688 1689 /* 1690 * If we're just here to trigger filtee loading then we're done. 1691 */ 1692 if (name == 0) 1693 return ((Sym *)0); 1694 1695 /* 1696 * If no filtees have been found for a filter, clean up any Pnode 1697 * structures and disable their search completely. For auxiliary 1698 * filters we can reselect the symbol search function so that we never 1699 * enter this routine again for this object. For standard filters we 1700 * use the null symbol routine. 1701 */ 1702 if (any == 0) { 1703 remove_pnode((Pnode *)dip->di_info); 1704 elf_disable_filtee(ilmp, dip); 1705 return ((Sym *)0); 1706 } 1707 1708 return ((Sym *)0); 1709 } 1710 1711 /* 1712 * Focal point for disabling error messages for auxiliary filters. As an 1713 * auxiliary filter allows for filtee use, but provides a fallback should a 1714 * filtee not exist (or fail to load), any errors generated as a consequence of 1715 * trying to load the filtees are typically suppressed. Setting RT_FL_SILENCERR 1716 * suppresses errors generated by eprint(), but insures a debug diagnostic is 1717 * produced. ldd(1) employs printf(), and here, the selection of whether to 1718 * print a diagnostic in regards to auxiliary filters is a little more complex. 1719 * 1720 * . The determination of whether to produce an ldd message, or a fatal 1721 * error message is driven by LML_FLG_TRC_ENABLE. 1722 * . More detailed ldd messages may also be driven off of LML_FLG_TRC_WARN, 1723 * (ldd -d/-r), LML_FLG_TRC_VERBOSE (ldd -v), LML_FLG_TRC_SEARCH (ldd -s), 1724 * and LML_FLG_TRC_UNREF/LML_FLG_TRC_UNUSED (ldd -U/-u). 1725 * 1726 * . If the calling object is lddstub, then several classes of message are 1727 * suppressed. The user isn't trying to diagnose lddstub, this is simply 1728 * a stub executable employed to preload a user specified library against. 1729 * 1730 * . If RT_FL_SILENCERR is in effect then any generic ldd() messages should 1731 * be suppressed. All detailed ldd messages should still be produced. 1732 */ 1733 Sym * 1734 elf_lookup_filtee(Slookup *slp, Rt_map **dlmp, uint_t *binfo, uint_t ndx) 1735 { 1736 Sym *sym; 1737 Dyninfo *dip = &DYNINFO(slp->sl_imap)[ndx]; 1738 int silent = 0; 1739 1740 /* 1741 * Make sure this entry is still acting as a filter. We may have tried 1742 * to process this previously, and disabled it if the filtee couldn't 1743 * be processed. However, other entries may provide different filtees 1744 * that are yet to be completed. 1745 */ 1746 if (dip->di_flags == 0) 1747 return ((Sym *)0); 1748 1749 /* 1750 * Indicate whether an error message is required should this filtee not 1751 * be found, based on the type of filter. 1752 */ 1753 if ((dip->di_flags & FLG_DI_AUXFLTR) && 1754 ((rtld_flags & (RT_FL_WARNFLTR | RT_FL_SILENCERR)) == 0)) { 1755 rtld_flags |= RT_FL_SILENCERR; 1756 silent = 1; 1757 } 1758 1759 sym = _elf_lookup_filtee(slp, dlmp, binfo, ndx); 1760 1761 if (silent) 1762 rtld_flags &= ~RT_FL_SILENCERR; 1763 1764 return (sym); 1765 } 1766 1767 /* 1768 * Compute the elf hash value (as defined in the ELF access library). 1769 * The form of the hash table is: 1770 * 1771 * |--------------| 1772 * | # of buckets | 1773 * |--------------| 1774 * | # of chains | 1775 * |--------------| 1776 * | bucket[] | 1777 * |--------------| 1778 * | chain[] | 1779 * |--------------| 1780 */ 1781 ulong_t 1782 elf_hash(const char *name) 1783 { 1784 uint_t hval = 0; 1785 1786 while (*name) { 1787 uint_t g; 1788 hval = (hval << 4) + *name++; 1789 if ((g = (hval & 0xf0000000)) != 0) 1790 hval ^= g >> 24; 1791 hval &= ~g; 1792 } 1793 return ((ulong_t)hval); 1794 } 1795 1796 /* 1797 * If flag argument has LKUP_SPEC set, we treat undefined symbols of type 1798 * function specially in the executable - if they have a value, even though 1799 * undefined, we use that value. This allows us to associate all references 1800 * to a function's address to a single place in the process: the plt entry 1801 * for that function in the executable. Calls to lookup from plt binding 1802 * routines do NOT set LKUP_SPEC in the flag. 1803 */ 1804 Sym * 1805 elf_find_sym(Slookup *slp, Rt_map **dlmp, uint_t *binfo) 1806 { 1807 const char *name = slp->sl_name; 1808 Rt_map *ilmp = slp->sl_imap; 1809 ulong_t hash = slp->sl_hash; 1810 uint_t ndx, htmp, buckets, *chainptr; 1811 Sym *sym, *symtabptr; 1812 char *strtabptr, *strtabname; 1813 uint_t flags1; 1814 Syminfo *sip; 1815 1816 /* 1817 * If we're only here to establish a symbols index, skip the diagnostic 1818 * used to trace a symbol search. 1819 */ 1820 if ((slp->sl_flags & LKUP_SYMNDX) == 0) 1821 DBG_CALL(Dbg_syms_lookup(ilmp, name, MSG_ORIG(MSG_STR_ELF))); 1822 1823 if (HASH(ilmp) == 0) 1824 return ((Sym *)0); 1825 1826 buckets = HASH(ilmp)[0]; 1827 /* LINTED */ 1828 htmp = (uint_t)hash % buckets; 1829 1830 /* 1831 * Get the first symbol on hash chain and initialize the string 1832 * and symbol table pointers. 1833 */ 1834 if ((ndx = HASH(ilmp)[htmp + 2]) == 0) 1835 return ((Sym *)0); 1836 1837 chainptr = HASH(ilmp) + 2 + buckets; 1838 strtabptr = STRTAB(ilmp); 1839 symtabptr = SYMTAB(ilmp); 1840 1841 while (ndx) { 1842 sym = symtabptr + ndx; 1843 strtabname = strtabptr + sym->st_name; 1844 1845 /* 1846 * Compare the symbol found with the name required. If the 1847 * names don't match continue with the next hash entry. 1848 */ 1849 if ((*strtabname++ != *name) || strcmp(strtabname, &name[1])) { 1850 if ((ndx = chainptr[ndx]) != 0) 1851 continue; 1852 return ((Sym *)0); 1853 } 1854 1855 /* 1856 * The Solaris ld does not put DT_VERSYM in the dynamic 1857 * section, but the GNU ld does. The GNU runtime linker 1858 * interprets the top bit of the 16-bit Versym value 1859 * (0x8000) as the "hidden" bit. If this bit is set, 1860 * the linker is supposed to act as if that symbol does 1861 * not exist. The hidden bit supports their versioning 1862 * scheme, which allows multiple incompatible functions 1863 * with the same name to exist at different versions 1864 * within an object. The Solaris linker does not support this 1865 * mechanism, or the model of interface evolution that 1866 * it allows, but we honor the hidden bit in GNU ld 1867 * produced objects in order to interoperate with them. 1868 */ 1869 if ((VERSYM(ilmp) != NULL) && 1870 ((VERSYM(ilmp)[ndx] & 0x8000) != 0)) { 1871 DBG_CALL(Dbg_syms_ignore_gnuver(ilmp, name, 1872 ndx, VERSYM(ilmp)[ndx])); 1873 if ((ndx = chainptr[ndx]) != 0) 1874 continue; 1875 return ((Sym *)0); 1876 } 1877 1878 /* 1879 * If we're only here to establish a symbols index, we're done. 1880 */ 1881 if (slp->sl_flags & LKUP_SYMNDX) 1882 return (sym); 1883 1884 /* 1885 * If we find a match and the symbol is defined, return the 1886 * symbol pointer and the link map in which it was found. 1887 */ 1888 if (sym->st_shndx != SHN_UNDEF) { 1889 *dlmp = ilmp; 1890 *binfo |= DBG_BINFO_FOUND; 1891 if ((FLAGS(ilmp) & FLG_RT_OBJINTPO) || 1892 ((FLAGS(ilmp) & FLG_RT_SYMINTPO) && 1893 is_sym_interposer(ilmp, sym))) 1894 *binfo |= DBG_BINFO_INTERPOSE; 1895 break; 1896 1897 /* 1898 * If we find a match and the symbol is undefined, the 1899 * symbol type is a function, and the value of the symbol 1900 * is non zero, then this is a special case. This allows 1901 * the resolution of a function address to the plt[] entry. 1902 * See SPARC ABI, Dynamic Linking, Function Addresses for 1903 * more details. 1904 */ 1905 } else if ((slp->sl_flags & LKUP_SPEC) && 1906 (FLAGS(ilmp) & FLG_RT_ISMAIN) && (sym->st_value != 0) && 1907 (ELF_ST_TYPE(sym->st_info) == STT_FUNC)) { 1908 *dlmp = ilmp; 1909 *binfo |= (DBG_BINFO_FOUND | DBG_BINFO_PLTADDR); 1910 if ((FLAGS(ilmp) & FLG_RT_OBJINTPO) || 1911 ((FLAGS(ilmp) & FLG_RT_SYMINTPO) && 1912 is_sym_interposer(ilmp, sym))) 1913 *binfo |= DBG_BINFO_INTERPOSE; 1914 return (sym); 1915 } 1916 1917 /* 1918 * Undefined symbol. 1919 */ 1920 return ((Sym *)0); 1921 } 1922 1923 /* 1924 * We've found a match. Determine if the defining object contains 1925 * symbol binding information. 1926 */ 1927 if ((sip = SYMINFO(ilmp)) != 0) 1928 sip += ndx; 1929 1930 /* 1931 * If this is a direct binding request, but the symbol definition has 1932 * disabled directly binding to it (presumably because the symbol 1933 * definition has been changed since the referring object was built), 1934 * indicate this failure so that the caller can fall back to a standard 1935 * symbol search. Clear any debug binding information for cleanliness. 1936 */ 1937 if (sip && (slp->sl_flags & LKUP_DIRECT) && 1938 (sip->si_flags & SYMINFO_FLG_NOEXTDIRECT)) { 1939 *binfo |= BINFO_DIRECTDIS; 1940 *binfo &= ~DBG_BINFO_MSK; 1941 return ((Sym *)0); 1942 } 1943 1944 /* 1945 * Determine whether this object is acting as a filter. 1946 */ 1947 if (((flags1 = FLAGS1(ilmp)) & MSK_RT_FILTER) == 0) 1948 return (sym); 1949 1950 /* 1951 * Determine if this object offers per-symbol filtering, and if so, 1952 * whether this symbol references a filtee. 1953 */ 1954 if (sip && (flags1 & (FL1_RT_SYMSFLTR | FL1_RT_SYMAFLTR))) { 1955 /* 1956 * If this is a standard filter reference, and no standard 1957 * filtees remain to be inspected, we're done. If this is an 1958 * auxiliary filter reference, and no auxiliary filtees remain, 1959 * we'll fall through in case any object filtering is available. 1960 */ 1961 if ((sip->si_flags & SYMINFO_FLG_FILTER) && 1962 (SYMSFLTRCNT(ilmp) == 0)) 1963 return ((Sym *)0); 1964 1965 if ((sip->si_flags & SYMINFO_FLG_FILTER) || 1966 ((sip->si_flags & SYMINFO_FLG_AUXILIARY) && 1967 SYMAFLTRCNT(ilmp))) { 1968 Sym * fsym; 1969 1970 /* 1971 * This symbol has an associated filtee. Lookup the 1972 * symbol in the filtee, and if it is found return it. 1973 * If the symbol doesn't exist, and this is a standard 1974 * filter, return an error, otherwise fall through to 1975 * catch any object filtering that may be available. 1976 */ 1977 if ((fsym = elf_lookup_filtee(slp, dlmp, binfo, 1978 sip->si_boundto)) != 0) 1979 return (fsym); 1980 if (sip->si_flags & SYMINFO_FLG_FILTER) 1981 return ((Sym *)0); 1982 } 1983 } 1984 1985 /* 1986 * Determine if this object provides global filtering. 1987 */ 1988 if (flags1 & (FL1_RT_OBJSFLTR | FL1_RT_OBJAFLTR)) { 1989 Sym * fsym; 1990 1991 if (OBJFLTRNDX(ilmp) != FLTR_DISABLED) { 1992 /* 1993 * This object has an associated filtee. Lookup the 1994 * symbol in the filtee, and if it is found return it. 1995 * If the symbol doesn't exist, and this is a standard 1996 * filter, return and error, otherwise return the symbol 1997 * within the filter itself. 1998 */ 1999 if ((fsym = elf_lookup_filtee(slp, dlmp, binfo, 2000 OBJFLTRNDX(ilmp))) != 0) 2001 return (fsym); 2002 } 2003 2004 if (flags1 & FL1_RT_OBJSFLTR) 2005 return ((Sym *)0); 2006 } 2007 return (sym); 2008 } 2009 2010 /* 2011 * Create a new Rt_map structure for an ELF object and initialize 2012 * all values. 2013 */ 2014 Rt_map * 2015 elf_new_lm(Lm_list *lml, const char *pname, const char *oname, Dyn *ld, 2016 ulong_t addr, ulong_t etext, Aliste lmco, ulong_t msize, ulong_t entry, 2017 ulong_t paddr, ulong_t padimsize, Mmap *mmaps, uint_t mmapcnt) 2018 { 2019 Rt_map *lmp; 2020 ulong_t base, fltr = 0, audit = 0, cfile = 0, crle = 0; 2021 Xword rpath = 0; 2022 Ehdr *ehdr = (Ehdr *)addr; 2023 2024 DBG_CALL(Dbg_file_elf(lml, pname, (ulong_t)ld, addr, msize, entry, 2025 lml->lm_lmidstr, lmco)); 2026 2027 /* 2028 * Allocate space for the link-map and private elf information. Once 2029 * these are allocated and initialized, we can use remove_so(0, lmp) to 2030 * tear down the link-map should any failures occur. 2031 */ 2032 if ((lmp = calloc(sizeof (Rt_map), 1)) == 0) 2033 return (0); 2034 if ((ELFPRV(lmp) = calloc(sizeof (Rt_elfp), 1)) == 0) { 2035 free(lmp); 2036 return (0); 2037 } 2038 2039 /* 2040 * All fields not filled in were set to 0 by calloc. 2041 */ 2042 ORIGNAME(lmp) = PATHNAME(lmp) = NAME(lmp) = (char *)pname; 2043 DYN(lmp) = ld; 2044 ADDR(lmp) = addr; 2045 MSIZE(lmp) = msize; 2046 ENTRY(lmp) = (Addr)entry; 2047 SYMINTP(lmp) = elf_find_sym; 2048 ETEXT(lmp) = etext; 2049 FCT(lmp) = &elf_fct; 2050 LIST(lmp) = lml; 2051 PADSTART(lmp) = paddr; 2052 PADIMLEN(lmp) = padimsize; 2053 THREADID(lmp) = rt_thr_self(); 2054 OBJFLTRNDX(lmp) = FLTR_DISABLED; 2055 SORTVAL(lmp) = -1; 2056 2057 MMAPS(lmp) = mmaps; 2058 MMAPCNT(lmp) = mmapcnt; 2059 ASSERT(mmapcnt != 0); 2060 2061 /* 2062 * If this is a shared object, add the base address to each address. 2063 * if this is an executable, use address as is. 2064 */ 2065 if (ehdr->e_type == ET_EXEC) { 2066 base = 0; 2067 FLAGS(lmp) |= FLG_RT_FIXED; 2068 } else 2069 base = addr; 2070 2071 /* 2072 * Fill in rest of the link map entries with information from the file's 2073 * dynamic structure. 2074 */ 2075 if (ld) { 2076 uint_t dyncnt = 0; 2077 Xword pltpadsz = 0; 2078 Rti_desc *rti; 2079 2080 /* CSTYLED */ 2081 for ( ; ld->d_tag != DT_NULL; ++ld, dyncnt++) { 2082 switch ((Xword)ld->d_tag) { 2083 case DT_SYMTAB: 2084 SYMTAB(lmp) = (void *)(ld->d_un.d_ptr + base); 2085 break; 2086 case DT_SUNW_SYMTAB: 2087 SUNWSYMTAB(lmp) = 2088 (void *)(ld->d_un.d_ptr + base); 2089 break; 2090 case DT_SUNW_SYMSZ: 2091 SUNWSYMSZ(lmp) = ld->d_un.d_val; 2092 break; 2093 case DT_STRTAB: 2094 STRTAB(lmp) = (void *)(ld->d_un.d_ptr + base); 2095 break; 2096 case DT_SYMENT: 2097 SYMENT(lmp) = ld->d_un.d_val; 2098 break; 2099 case DT_FEATURE_1: 2100 ld->d_un.d_val |= DTF_1_PARINIT; 2101 if (ld->d_un.d_val & DTF_1_CONFEXP) 2102 crle = 1; 2103 break; 2104 case DT_MOVESZ: 2105 MOVESZ(lmp) = ld->d_un.d_val; 2106 FLAGS(lmp) |= FLG_RT_MOVE; 2107 break; 2108 case DT_MOVEENT: 2109 MOVEENT(lmp) = ld->d_un.d_val; 2110 break; 2111 case DT_MOVETAB: 2112 MOVETAB(lmp) = (void *)(ld->d_un.d_ptr + base); 2113 break; 2114 case DT_REL: 2115 case DT_RELA: 2116 /* 2117 * At this time we can only handle 1 type of 2118 * relocation per object. 2119 */ 2120 REL(lmp) = (void *)(ld->d_un.d_ptr + base); 2121 break; 2122 case DT_RELSZ: 2123 case DT_RELASZ: 2124 RELSZ(lmp) = ld->d_un.d_val; 2125 break; 2126 case DT_RELENT: 2127 case DT_RELAENT: 2128 RELENT(lmp) = ld->d_un.d_val; 2129 break; 2130 case DT_RELCOUNT: 2131 case DT_RELACOUNT: 2132 RELACOUNT(lmp) = (uint_t)ld->d_un.d_val; 2133 break; 2134 case DT_TEXTREL: 2135 FLAGS1(lmp) |= FL1_RT_TEXTREL; 2136 break; 2137 case DT_HASH: 2138 HASH(lmp) = (uint_t *)(ld->d_un.d_ptr + base); 2139 break; 2140 case DT_PLTGOT: 2141 PLTGOT(lmp) = (uint_t *)(ld->d_un.d_ptr + base); 2142 break; 2143 case DT_PLTRELSZ: 2144 PLTRELSZ(lmp) = ld->d_un.d_val; 2145 break; 2146 case DT_JMPREL: 2147 JMPREL(lmp) = (void *)(ld->d_un.d_ptr + base); 2148 break; 2149 case DT_INIT: 2150 if (ld->d_un.d_ptr != NULL) 2151 INIT(lmp) = 2152 (void (*)())(ld->d_un.d_ptr + base); 2153 break; 2154 case DT_FINI: 2155 if (ld->d_un.d_ptr != NULL) 2156 FINI(lmp) = 2157 (void (*)())(ld->d_un.d_ptr + base); 2158 break; 2159 case DT_INIT_ARRAY: 2160 INITARRAY(lmp) = (Addr *)(ld->d_un.d_ptr + 2161 base); 2162 break; 2163 case DT_INIT_ARRAYSZ: 2164 INITARRAYSZ(lmp) = (uint_t)ld->d_un.d_val; 2165 break; 2166 case DT_FINI_ARRAY: 2167 FINIARRAY(lmp) = (Addr *)(ld->d_un.d_ptr + 2168 base); 2169 break; 2170 case DT_FINI_ARRAYSZ: 2171 FINIARRAYSZ(lmp) = (uint_t)ld->d_un.d_val; 2172 break; 2173 case DT_PREINIT_ARRAY: 2174 PREINITARRAY(lmp) = (Addr *)(ld->d_un.d_ptr + 2175 base); 2176 break; 2177 case DT_PREINIT_ARRAYSZ: 2178 PREINITARRAYSZ(lmp) = (uint_t)ld->d_un.d_val; 2179 break; 2180 case DT_RPATH: 2181 case DT_RUNPATH: 2182 rpath = ld->d_un.d_val; 2183 break; 2184 case DT_FILTER: 2185 fltr = ld->d_un.d_val; 2186 OBJFLTRNDX(lmp) = dyncnt; 2187 FLAGS1(lmp) |= FL1_RT_OBJSFLTR; 2188 break; 2189 case DT_AUXILIARY: 2190 if (!(rtld_flags & RT_FL_NOAUXFLTR)) { 2191 fltr = ld->d_un.d_val; 2192 OBJFLTRNDX(lmp) = dyncnt; 2193 } 2194 FLAGS1(lmp) |= FL1_RT_OBJAFLTR; 2195 break; 2196 case DT_SUNW_FILTER: 2197 SYMSFLTRCNT(lmp)++; 2198 FLAGS1(lmp) |= FL1_RT_SYMSFLTR; 2199 break; 2200 case DT_SUNW_AUXILIARY: 2201 if (!(rtld_flags & RT_FL_NOAUXFLTR)) { 2202 SYMAFLTRCNT(lmp)++; 2203 } 2204 FLAGS1(lmp) |= FL1_RT_SYMAFLTR; 2205 break; 2206 case DT_DEPAUDIT: 2207 if (!(rtld_flags & RT_FL_NOAUDIT)) 2208 audit = ld->d_un.d_val; 2209 break; 2210 case DT_CONFIG: 2211 cfile = ld->d_un.d_val; 2212 break; 2213 case DT_DEBUG: 2214 /* 2215 * DT_DEBUG entries are only created in 2216 * dynamic objects that require an interpretor 2217 * (ie. all dynamic executables and some shared 2218 * objects), and provide for a hand-shake with 2219 * debuggers. This entry is initialized to 2220 * zero by the link-editor. If a debugger has 2221 * us and updated this entry set the debugger 2222 * flag, and finish initializing the debugging 2223 * structure (see setup() also). Switch off any 2224 * configuration object use as most debuggers 2225 * can't handle fixed dynamic executables as 2226 * dependencies, and we can't handle requests 2227 * like object padding for alternative objects. 2228 */ 2229 if (ld->d_un.d_ptr) 2230 rtld_flags |= 2231 (RT_FL_DEBUGGER | RT_FL_NOOBJALT); 2232 ld->d_un.d_ptr = (Addr)&r_debug; 2233 break; 2234 case DT_VERNEED: 2235 VERNEED(lmp) = (Verneed *)(ld->d_un.d_ptr + 2236 base); 2237 break; 2238 case DT_VERNEEDNUM: 2239 /* LINTED */ 2240 VERNEEDNUM(lmp) = (int)ld->d_un.d_val; 2241 break; 2242 case DT_VERDEF: 2243 VERDEF(lmp) = (Verdef *)(ld->d_un.d_ptr + base); 2244 break; 2245 case DT_VERDEFNUM: 2246 /* LINTED */ 2247 VERDEFNUM(lmp) = (int)ld->d_un.d_val; 2248 break; 2249 case DT_VERSYM: 2250 /* 2251 * The Solaris ld does not produce DT_VERSYM, 2252 * but the GNU ld does, in order to support 2253 * their style of versioning, which differs 2254 * from ours in some ways, while using the 2255 * same data structures. The presence of 2256 * DT_VERSYM therefore means that GNU 2257 * versioning rules apply to the given file. 2258 * If DT_VERSYM is not present, then Solaris 2259 * versioning rules apply. 2260 */ 2261 VERSYM(lmp) = (Versym *)(ld->d_un.d_ptr + base); 2262 break; 2263 case DT_BIND_NOW: 2264 if ((ld->d_un.d_val & DF_BIND_NOW) && 2265 ((rtld_flags2 & RT_FL2_BINDLAZY) == 0)) { 2266 MODE(lmp) |= RTLD_NOW; 2267 MODE(lmp) &= ~RTLD_LAZY; 2268 } 2269 break; 2270 case DT_FLAGS: 2271 if (ld->d_un.d_val & DF_SYMBOLIC) 2272 FLAGS1(lmp) |= FL1_RT_SYMBOLIC; 2273 if (ld->d_un.d_val & DF_TEXTREL) 2274 FLAGS1(lmp) |= FL1_RT_TEXTREL; 2275 if ((ld->d_un.d_val & DF_BIND_NOW) && 2276 ((rtld_flags2 & RT_FL2_BINDLAZY) == 0)) { 2277 MODE(lmp) |= RTLD_NOW; 2278 MODE(lmp) &= ~RTLD_LAZY; 2279 } 2280 /* 2281 * Capture any static TLS use, and enforce that 2282 * this object be non-deletable. 2283 */ 2284 if (ld->d_un.d_val & DF_STATIC_TLS) { 2285 FLAGS1(lmp) |= FL1_RT_TLSSTAT; 2286 MODE(lmp) |= RTLD_NODELETE; 2287 } 2288 break; 2289 case DT_FLAGS_1: 2290 if (ld->d_un.d_val & DF_1_DISPRELPND) 2291 FLAGS1(lmp) |= FL1_RT_DISPREL; 2292 if (ld->d_un.d_val & DF_1_GROUP) 2293 FLAGS(lmp) |= 2294 (FLG_RT_SETGROUP | FLG_RT_HANDLE); 2295 if ((ld->d_un.d_val & DF_1_NOW) && 2296 ((rtld_flags2 & RT_FL2_BINDLAZY) == 0)) { 2297 MODE(lmp) |= RTLD_NOW; 2298 MODE(lmp) &= ~RTLD_LAZY; 2299 } 2300 if (ld->d_un.d_val & DF_1_NODELETE) 2301 MODE(lmp) |= RTLD_NODELETE; 2302 if (ld->d_un.d_val & DF_1_INITFIRST) 2303 FLAGS(lmp) |= FLG_RT_INITFRST; 2304 if (ld->d_un.d_val & DF_1_NOOPEN) 2305 FLAGS(lmp) |= FLG_RT_NOOPEN; 2306 if (ld->d_un.d_val & DF_1_LOADFLTR) 2307 FLAGS(lmp) |= FLG_RT_LOADFLTR; 2308 if (ld->d_un.d_val & DF_1_NODUMP) 2309 FLAGS(lmp) |= FLG_RT_NODUMP; 2310 if (ld->d_un.d_val & DF_1_CONFALT) 2311 crle = 1; 2312 if (ld->d_un.d_val & DF_1_DIRECT) 2313 FLAGS1(lmp) |= FL1_RT_DIRECT; 2314 if (ld->d_un.d_val & DF_1_NODEFLIB) 2315 FLAGS1(lmp) |= FL1_RT_NODEFLIB; 2316 if (ld->d_un.d_val & DF_1_ENDFILTEE) 2317 FLAGS1(lmp) |= FL1_RT_ENDFILTE; 2318 if (ld->d_un.d_val & DF_1_TRANS) 2319 FLAGS(lmp) |= FLG_RT_TRANS; 2320 #ifndef EXPAND_RELATIVE 2321 if (ld->d_un.d_val & DF_1_ORIGIN) 2322 FLAGS1(lmp) |= FL1_RT_RELATIVE; 2323 #endif 2324 /* 2325 * Global auditing is only meaningful when 2326 * specified by the initiating object of the 2327 * process - typically the dynamic executable. 2328 * If this is the initiaiting object, its link- 2329 * map will not yet have been added to the 2330 * link-map list, and consequently the link-map 2331 * list is empty. (see setup()). 2332 */ 2333 if (ld->d_un.d_val & DF_1_GLOBAUDIT) { 2334 if (lml_main.lm_head == 0) 2335 FLAGS1(lmp) |= FL1_RT_GLOBAUD; 2336 else 2337 DBG_CALL(Dbg_audit_ignore(lmp)); 2338 } 2339 2340 /* 2341 * If this object identifies itself as an 2342 * interposer, but relocation processing has 2343 * already started, then demote it. It's too 2344 * late to guarantee complete interposition. 2345 */ 2346 /* BEGIN CSTYLED */ 2347 if (ld->d_un.d_val & 2348 (DF_1_INTERPOSE | DF_1_SYMINTPOSE)) { 2349 if (lml->lm_flags & LML_FLG_STARTREL) { 2350 DBG_CALL(Dbg_util_intoolate(lmp)); 2351 if (lml->lm_flags & LML_FLG_TRC_ENABLE) 2352 (void) printf( 2353 MSG_INTL(MSG_LDD_REL_ERR2), 2354 NAME(lmp)); 2355 } else if (ld->d_un.d_val & DF_1_INTERPOSE) 2356 FLAGS(lmp) |= FLG_RT_OBJINTPO; 2357 else 2358 FLAGS(lmp) |= FLG_RT_SYMINTPO; 2359 } 2360 /* END CSTYLED */ 2361 break; 2362 case DT_SYMINFO: 2363 SYMINFO(lmp) = (Syminfo *)(ld->d_un.d_ptr + 2364 base); 2365 break; 2366 case DT_SYMINENT: 2367 SYMINENT(lmp) = ld->d_un.d_val; 2368 break; 2369 case DT_PLTPAD: 2370 PLTPAD(lmp) = (void *)(ld->d_un.d_ptr + base); 2371 break; 2372 case DT_PLTPADSZ: 2373 pltpadsz = ld->d_un.d_val; 2374 break; 2375 case DT_SUNW_RTLDINF: 2376 /* 2377 * Maintain a list of RTLDINFO structures. 2378 * Typically, libc is the only supplier, and 2379 * only one structure is provided. However, 2380 * multiple suppliers and multiple structures 2381 * are supported. For example, one structure 2382 * may provide thread_init, and another 2383 * structure may provide atexit reservations. 2384 */ 2385 if ((rti = alist_append(&lml->lm_rti, 0, 2386 sizeof (Rti_desc), AL_CNT_RTLDINFO)) == 0) { 2387 remove_so(0, lmp); 2388 return (0); 2389 } 2390 rti->rti_lmp = lmp; 2391 rti->rti_info = (void *)(ld->d_un.d_ptr + base); 2392 break; 2393 case DT_SUNW_SORTENT: 2394 SUNWSORTENT(lmp) = ld->d_un.d_val; 2395 break; 2396 case DT_SUNW_SYMSORT: 2397 SUNWSYMSORT(lmp) = 2398 (void *)(ld->d_un.d_ptr + base); 2399 break; 2400 case DT_SUNW_SYMSORTSZ: 2401 SUNWSYMSORTSZ(lmp) = ld->d_un.d_val; 2402 break; 2403 case DT_DEPRECATED_SPARC_REGISTER: 2404 case M_DT_REGISTER: 2405 FLAGS(lmp) |= FLG_RT_REGSYMS; 2406 break; 2407 case M_DT_PLTRESERVE: 2408 PLTRESERVE(lmp) = (void *)(ld->d_un.d_ptr + 2409 base); 2410 break; 2411 } 2412 } 2413 2414 2415 if (PLTPAD(lmp)) { 2416 if (pltpadsz == (Xword)0) 2417 PLTPAD(lmp) = 0; 2418 else 2419 PLTPADEND(lmp) = (void *)((Addr)PLTPAD(lmp) + 2420 pltpadsz); 2421 } 2422 2423 /* 2424 * Allocate Dynamic Info structure 2425 */ 2426 if ((DYNINFO(lmp) = calloc((size_t)dyncnt, 2427 sizeof (Dyninfo))) == 0) { 2428 remove_so(0, lmp); 2429 return (0); 2430 } 2431 DYNINFOCNT(lmp) = dyncnt; 2432 } 2433 2434 /* 2435 * A dynsym contains only global functions. We want to have 2436 * a version of it that also includes local functions, so that 2437 * dladdr() will be able to report names for local functions 2438 * when used to generate a stack trace for a stripped file. 2439 * This version of the dynsym is provided via DT_SUNW_SYMTAB. 2440 * 2441 * In producing DT_SUNW_SYMTAB, ld uses a non-obvious trick 2442 * in order to avoid having to have two copies of the global 2443 * symbols held in DT_SYMTAB: The local symbols are placed in 2444 * a separate section than the globals in the dynsym, but the 2445 * linker conspires to put the data for these two sections adjacent 2446 * to each other. DT_SUNW_SYMTAB points at the top of the local 2447 * symbols, and DT_SUNW_SYMSZ is the combined length of both tables. 2448 * 2449 * If the two sections are not adjacent, then something went wrong 2450 * at link time. We use ASSERT to kill the process if this is 2451 * a debug build. In a production build, we will silently ignore 2452 * the presence of the .ldynsym and proceed. We can detect this 2453 * situation by checking to see that DT_SYMTAB lies in 2454 * the range given by DT_SUNW_SYMTAB/DT_SUNW_SYMSZ. 2455 */ 2456 if ((SUNWSYMTAB(lmp) != NULL) && 2457 (((char *)SYMTAB(lmp) <= (char *)SUNWSYMTAB(lmp)) || 2458 (((char *)SYMTAB(lmp) >= 2459 (SUNWSYMSZ(lmp) + (char *)SUNWSYMTAB(lmp)))))) { 2460 ASSERT(0); 2461 SUNWSYMTAB(lmp) = NULL; 2462 SUNWSYMSZ(lmp) = 0; 2463 } 2464 2465 /* 2466 * If configuration file use hasn't been disabled, and a configuration 2467 * file hasn't already been set via an environment variable, see if any 2468 * application specific configuration file is specified. An LD_CONFIG 2469 * setting is used first, but if this image was generated via crle(1) 2470 * then a default configuration file is a fall-back. 2471 */ 2472 if ((!(rtld_flags & RT_FL_NOCFG)) && (config->c_name == 0)) { 2473 if (cfile) 2474 config->c_name = (const char *)(cfile + 2475 (char *)STRTAB(lmp)); 2476 else if (crle) { 2477 rtld_flags |= RT_FL_CONFAPP; 2478 #ifndef EXPAND_RELATIVE 2479 FLAGS1(lmp) |= FL1_RT_RELATIVE; 2480 #endif 2481 } 2482 } 2483 2484 if (rpath) 2485 RPATH(lmp) = (char *)(rpath + (char *)STRTAB(lmp)); 2486 if (fltr) { 2487 /* 2488 * If this object is a global filter, duplicate the filtee 2489 * string name(s) so that REFNAME() is available in core files. 2490 * This cludge was useful for debuggers at one point, but only 2491 * when the filtee name was an individual full path. 2492 */ 2493 if ((REFNAME(lmp) = strdup(fltr + (char *)STRTAB(lmp))) == 0) { 2494 remove_so(0, lmp); 2495 return (0); 2496 } 2497 } 2498 2499 if (rtld_flags & RT_FL_RELATIVE) 2500 FLAGS1(lmp) |= FL1_RT_RELATIVE; 2501 2502 /* 2503 * For Intel ABI compatibility. It's possible that a JMPREL can be 2504 * specified without any other relocations (e.g. a dynamic executable 2505 * normally only contains .plt relocations). If this is the case then 2506 * no REL, RELSZ or RELENT will have been created. For us to be able 2507 * to traverse the .plt relocations under LD_BIND_NOW we need to know 2508 * the RELENT for these relocations. Refer to elf_reloc() for more 2509 * details. 2510 */ 2511 if (!RELENT(lmp) && JMPREL(lmp)) 2512 RELENT(lmp) = sizeof (Rel); 2513 2514 /* 2515 * Establish any per-object auditing. If we're establishing `main's 2516 * link-map its too early to go searching for audit objects so just 2517 * hold the object name for later (see setup()). 2518 */ 2519 if (audit) { 2520 char *cp = audit + (char *)STRTAB(lmp); 2521 2522 if (*cp) { 2523 if (((AUDITORS(lmp) = 2524 calloc(1, sizeof (Audit_desc))) == 0) || 2525 ((AUDITORS(lmp)->ad_name = strdup(cp)) == 0)) { 2526 remove_so(0, lmp); 2527 return (0); 2528 } 2529 if (lml_main.lm_head) { 2530 if (audit_setup(lmp, AUDITORS(lmp), 0) == 0) { 2531 remove_so(0, lmp); 2532 return (0); 2533 } 2534 FLAGS1(lmp) |= AUDITORS(lmp)->ad_flags; 2535 lml->lm_flags |= LML_FLG_LOCAUDIT; 2536 } 2537 } 2538 } 2539 2540 if ((CONDVAR(lmp) = rt_cond_create()) == 0) { 2541 remove_so(0, lmp); 2542 return (0); 2543 } 2544 if (oname && ((append_alias(lmp, oname, 0)) == 0)) { 2545 remove_so(0, lmp); 2546 return (0); 2547 } 2548 2549 /* 2550 * Add the mapped object to the end of the link map list. 2551 */ 2552 lm_append(lml, lmco, lmp); 2553 return (lmp); 2554 } 2555 2556 /* 2557 * Assign hardware/software capabilities. 2558 */ 2559 void 2560 cap_assign(Cap *cap, Rt_map *lmp) 2561 { 2562 while (cap->c_tag != CA_SUNW_NULL) { 2563 switch (cap->c_tag) { 2564 case CA_SUNW_HW_1: 2565 HWCAP(lmp) = cap->c_un.c_val; 2566 break; 2567 case CA_SUNW_SF_1: 2568 SFCAP(lmp) = cap->c_un.c_val; 2569 } 2570 cap++; 2571 } 2572 } 2573 2574 /* 2575 * Map in an ELF object. 2576 * Takes an open file descriptor for the object to map and its pathname; returns 2577 * a pointer to a Rt_map structure for this object, or 0 on error. 2578 */ 2579 static Rt_map * 2580 elf_map_so(Lm_list *lml, Aliste lmco, const char *pname, const char *oname, 2581 int fd) 2582 { 2583 int i; /* general temporary */ 2584 Off memsize = 0; /* total memory size of pathname */ 2585 Off mentry; /* entry point */ 2586 Ehdr *ehdr; /* ELF header of ld.so */ 2587 Phdr *phdr; /* first Phdr in file */ 2588 Phdr *phdr0; /* Saved first Phdr in file */ 2589 Phdr *pptr; /* working Phdr */ 2590 Phdr *fph = 0; /* first loadable Phdr */ 2591 Phdr *lph; /* last loadable Phdr */ 2592 Phdr *lfph = 0; /* last loadable (filesz != 0) Phdr */ 2593 Phdr *lmph = 0; /* last loadable (memsz != 0) Phdr */ 2594 Phdr *swph = 0; /* program header for SUNWBSS */ 2595 Phdr *tlph = 0; /* program header for PT_TLS */ 2596 Phdr *unwindph = 0; /* program header for PT_SUNW_UNWIND */ 2597 Cap *cap = 0; /* program header for SUNWCAP */ 2598 Dyn *mld = 0; /* DYNAMIC structure for pathname */ 2599 size_t size; /* size of elf and program headers */ 2600 caddr_t faddr = 0; /* mapping address of pathname */ 2601 Rt_map *lmp; /* link map created */ 2602 caddr_t paddr; /* start of padded image */ 2603 Off plen; /* size of image including padding */ 2604 Half etype; 2605 int fixed; 2606 Mmap *mmaps; 2607 uint_t mmapcnt = 0; 2608 Xword align = 0; 2609 2610 /* LINTED */ 2611 ehdr = (Ehdr *)fmap->fm_maddr; 2612 2613 /* 2614 * If this a relocatable object then special processing is required. 2615 */ 2616 if ((etype = ehdr->e_type) == ET_REL) 2617 return (elf_obj_file(lml, lmco, pname, fd)); 2618 2619 /* 2620 * If this isn't a dynamic executable or shared object we can't process 2621 * it. If this is a dynamic executable then all addresses are fixed. 2622 */ 2623 if (etype == ET_EXEC) { 2624 fixed = 1; 2625 } else if (etype == ET_DYN) { 2626 fixed = 0; 2627 } else { 2628 Conv_inv_buf_t inv_buf; 2629 2630 eprintf(lml, ERR_ELF, MSG_INTL(MSG_GEN_BADTYPE), pname, 2631 conv_ehdr_type(etype, 0, &inv_buf)); 2632 return (0); 2633 } 2634 2635 /* 2636 * If our original mapped page was not large enough to hold all the 2637 * program headers remap them. 2638 */ 2639 size = (size_t)((char *)ehdr->e_phoff + 2640 (ehdr->e_phnum * ehdr->e_phentsize)); 2641 if (size > fmap->fm_fsize) { 2642 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_GEN_CORTRUNC), pname); 2643 return (0); 2644 } 2645 if (size > fmap->fm_msize) { 2646 fmap_setup(); 2647 if ((fmap->fm_maddr = mmap(fmap->fm_maddr, size, PROT_READ, 2648 fmap->fm_mflags, fd, 0)) == MAP_FAILED) { 2649 int err = errno; 2650 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_SYS_MMAP), pname, 2651 strerror(err)); 2652 return (0); 2653 } 2654 fmap->fm_msize = size; 2655 /* LINTED */ 2656 ehdr = (Ehdr *)fmap->fm_maddr; 2657 } 2658 /* LINTED */ 2659 phdr0 = phdr = (Phdr *)((char *)ehdr + ehdr->e_ehsize); 2660 2661 /* 2662 * Get entry point. 2663 */ 2664 mentry = ehdr->e_entry; 2665 2666 /* 2667 * Point at program headers and perform some basic validation. 2668 */ 2669 for (i = 0, pptr = phdr; i < (int)ehdr->e_phnum; i++, 2670 pptr = (Phdr *)((Off)pptr + ehdr->e_phentsize)) { 2671 if ((pptr->p_type == PT_LOAD) || 2672 (pptr->p_type == PT_SUNWBSS)) { 2673 2674 if (fph == 0) { 2675 fph = pptr; 2676 /* LINTED argument lph is initialized in first pass */ 2677 } else if (pptr->p_vaddr <= lph->p_vaddr) { 2678 eprintf(lml, ERR_ELF, 2679 MSG_INTL(MSG_GEN_INVPRGHDR), pname); 2680 return (0); 2681 } 2682 2683 lph = pptr; 2684 2685 if (pptr->p_memsz) 2686 lmph = pptr; 2687 if (pptr->p_filesz) 2688 lfph = pptr; 2689 if (pptr->p_type == PT_SUNWBSS) 2690 swph = pptr; 2691 if (pptr->p_align > align) 2692 align = pptr->p_align; 2693 2694 } else if (pptr->p_type == PT_DYNAMIC) { 2695 mld = (Dyn *)(pptr->p_vaddr); 2696 } else if ((pptr->p_type == PT_TLS) && pptr->p_memsz) { 2697 tlph = pptr; 2698 } else if (pptr->p_type == PT_SUNWCAP) { 2699 cap = (Cap *)(pptr->p_vaddr); 2700 } else if (pptr->p_type == PT_SUNW_UNWIND) { 2701 unwindph = pptr; 2702 } 2703 } 2704 2705 #if defined(MAP_ALIGN) 2706 /* 2707 * Make sure the maximum page alignment is a power of 2 >= the default 2708 * segment alignment, for use with MAP_ALIGN. 2709 */ 2710 align = S_ROUND(align, M_SEGM_ALIGN); 2711 #endif 2712 2713 /* 2714 * We'd better have at least one loadable segment, together with some 2715 * specified file and memory size. 2716 */ 2717 if ((fph == 0) || (lmph == 0) || (lfph == 0)) { 2718 eprintf(lml, ERR_ELF, MSG_INTL(MSG_GEN_NOLOADSEG), pname); 2719 return (0); 2720 } 2721 2722 /* 2723 * Check that the files size accounts for the loadable sections 2724 * we're going to map in (failure to do this may cause spurious 2725 * bus errors if we're given a truncated file). 2726 */ 2727 if (fmap->fm_fsize < ((size_t)lfph->p_offset + lfph->p_filesz)) { 2728 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_GEN_CORTRUNC), pname); 2729 return (0); 2730 } 2731 2732 /* 2733 * Memsize must be page rounded so that if we add object padding 2734 * at the end it will start at the beginning of a page. 2735 */ 2736 plen = memsize = M_PROUND((lmph->p_vaddr + lmph->p_memsz) - 2737 M_PTRUNC((ulong_t)fph->p_vaddr)); 2738 2739 /* 2740 * Determine if an existing mapping is acceptable. 2741 */ 2742 if (interp && (lml->lm_flags & LML_FLG_BASELM) && 2743 (strcmp(pname, interp->i_name) == 0)) { 2744 /* 2745 * If this is the interpreter then it has already been mapped 2746 * and we have the address so don't map it again. Note that 2747 * the common occurrence of a reference to the interpretor 2748 * (libdl -> ld.so.1) will have been caught during filter 2749 * initialization (see elf_lookup_filtee()). However, some 2750 * ELF implementations are known to record libc.so.1 as the 2751 * interpretor, and thus this test catches this behavior. 2752 */ 2753 paddr = faddr = interp->i_faddr; 2754 2755 } else if ((fixed == 0) && (r_debug.rtd_objpad == 0) && 2756 (memsize <= fmap->fm_msize) && ((fph->p_flags & PF_W) == 0) && 2757 (fph == lph) && (fph->p_filesz == fph->p_memsz) && 2758 (((Xword)fmap->fm_maddr % align) == 0)) { 2759 size_t rsize; 2760 2761 /* 2762 * If the file contains a single segment, and the mapping 2763 * required has already been established from the initial fmap 2764 * mapping, then we don't need to do anything more. Reset the 2765 * fmap address so that any later files start a new fmap. This 2766 * is really an optimization for filters, such as libdl.so, 2767 * libthread, etc. that are constructed to be a single text 2768 * segment. 2769 */ 2770 paddr = faddr = fmap->fm_maddr; 2771 2772 /* 2773 * Free any unused mapping by assigning the fmap buffer to the 2774 * unused region. fmap_setup() will unmap this area and 2775 * establish defaults for future mappings. 2776 */ 2777 rsize = M_PROUND(fph->p_filesz); 2778 fmap->fm_maddr += rsize; 2779 fmap->fm_msize -= rsize; 2780 fmap_setup(); 2781 } 2782 2783 /* 2784 * Allocate a mapping array to retain mapped segment information. 2785 */ 2786 if ((mmaps = calloc(ehdr->e_phnum, sizeof (Mmap))) == 0) 2787 return (0); 2788 2789 /* 2790 * If we're reusing an existing mapping determine the objects etext 2791 * address. Otherwise map the file (which will calculate the etext 2792 * address as part of the mapping process). 2793 */ 2794 if (faddr) { 2795 caddr_t base; 2796 2797 if (fixed) 2798 base = 0; 2799 else 2800 base = faddr; 2801 2802 /* LINTED */ 2803 phdr0 = phdr = (Phdr *)((char *)faddr + ehdr->e_ehsize); 2804 2805 for (i = 0, pptr = phdr; i < (int)ehdr->e_phnum; i++, 2806 pptr = (Phdr *)((Off)pptr + ehdr->e_phentsize)) { 2807 if (pptr->p_type != PT_LOAD) 2808 continue; 2809 2810 mmaps[mmapcnt].m_vaddr = (pptr->p_vaddr + base); 2811 mmaps[mmapcnt].m_msize = pptr->p_memsz; 2812 mmaps[mmapcnt].m_fsize = pptr->p_filesz; 2813 mmaps[mmapcnt].m_perm = (PROT_READ | PROT_EXEC); 2814 mmapcnt++; 2815 2816 if (!(pptr->p_flags & PF_W)) { 2817 fmap->fm_etext = (ulong_t)pptr->p_vaddr + 2818 (ulong_t)pptr->p_memsz + 2819 (ulong_t)(fixed ? 0 : faddr); 2820 } 2821 } 2822 } else { 2823 /* 2824 * Map the file. 2825 */ 2826 if (!(faddr = elf_map_it(lml, pname, memsize, ehdr, fph, lph, 2827 &phdr, &paddr, &plen, fixed, fd, align, mmaps, &mmapcnt))) 2828 return (0); 2829 } 2830 2831 /* 2832 * Calculate absolute base addresses and entry points. 2833 */ 2834 if (!fixed) { 2835 if (mld) 2836 /* LINTED */ 2837 mld = (Dyn *)((Off)mld + faddr); 2838 if (cap) 2839 /* LINTED */ 2840 cap = (Cap *)((Off)cap + faddr); 2841 mentry += (Off)faddr; 2842 } 2843 2844 /* 2845 * Create new link map structure for newly mapped shared object. 2846 */ 2847 if (!(lmp = elf_new_lm(lml, pname, oname, mld, (ulong_t)faddr, 2848 fmap->fm_etext, lmco, memsize, mentry, (ulong_t)paddr, plen, mmaps, 2849 mmapcnt))) { 2850 (void) munmap((caddr_t)faddr, memsize); 2851 return (0); 2852 } 2853 2854 /* 2855 * Start the system loading in the ELF information we'll be processing. 2856 */ 2857 if (REL(lmp)) { 2858 (void) madvise((void *)ADDR(lmp), (uintptr_t)REL(lmp) + 2859 (uintptr_t)RELSZ(lmp) - (uintptr_t)ADDR(lmp), 2860 MADV_WILLNEED); 2861 } 2862 2863 /* 2864 * If this shared object contains any special segments, record them. 2865 */ 2866 if (swph) { 2867 FLAGS(lmp) |= FLG_RT_SUNWBSS; 2868 SUNWBSS(lmp) = phdr + (swph - phdr0); 2869 } 2870 if (tlph && (tls_assign(lml, lmp, (phdr + (tlph - phdr0))) == 0)) { 2871 remove_so(lml, lmp); 2872 return (0); 2873 } 2874 2875 if (unwindph) 2876 PTUNWIND(lmp) = phdr + (unwindph - phdr0); 2877 2878 if (cap) 2879 cap_assign(cap, lmp); 2880 2881 return (lmp); 2882 } 2883 2884 /* 2885 * Function to correct protection settings. Segments are all mapped initially 2886 * with permissions as given in the segment header. We need to turn on write 2887 * permissions on a text segment if there are any relocations against that 2888 * segment, and them turn write permission back off again before returning 2889 * control to the user. This function turns the permission on or off depending 2890 * on the value of the argument. 2891 */ 2892 int 2893 elf_set_prot(Rt_map *lmp, int permission) 2894 { 2895 Mmap *mmaps; 2896 2897 /* 2898 * If this is an allocated image (ie. a relocatable object) we can't 2899 * mprotect() anything. 2900 */ 2901 if (FLAGS(lmp) & FLG_RT_IMGALLOC) 2902 return (1); 2903 2904 DBG_CALL(Dbg_file_prot(lmp, permission)); 2905 2906 for (mmaps = MMAPS(lmp); mmaps->m_vaddr; mmaps++) { 2907 if (mmaps->m_perm & PROT_WRITE) 2908 continue; 2909 2910 if (mprotect(mmaps->m_vaddr, mmaps->m_msize, 2911 (mmaps->m_perm | permission)) == -1) { 2912 int err = errno; 2913 eprintf(LIST(lmp), ERR_FATAL, MSG_INTL(MSG_SYS_MPROT), 2914 NAME(lmp), strerror(err)); 2915 return (0); 2916 } 2917 } 2918 return (1); 2919 } 2920 2921 /* 2922 * Build full pathname of shared object from given directory name and filename. 2923 */ 2924 static char * 2925 elf_get_so(const char *dir, const char *file) 2926 { 2927 static char pname[PATH_MAX]; 2928 2929 (void) snprintf(pname, PATH_MAX, MSG_ORIG(MSG_FMT_PATH), dir, file); 2930 return (pname); 2931 } 2932 2933 /* 2934 * The copy relocation is recorded in a copy structure which will be applied 2935 * after all other relocations are carried out. This provides for copying data 2936 * that must be relocated itself (ie. pointers in shared objects). This 2937 * structure also provides a means of binding RTLD_GROUP dependencies to any 2938 * copy relocations that have been taken from any group members. 2939 * 2940 * If the size of the .bss area available for the copy information is not the 2941 * same as the source of the data inform the user if we're under ldd(1) control 2942 * (this checking was only established in 5.3, so by only issuing an error via 2943 * ldd(1) we maintain the standard set by previous releases). 2944 */ 2945 int 2946 elf_copy_reloc(char *name, Sym *rsym, Rt_map *rlmp, void *radd, Sym *dsym, 2947 Rt_map *dlmp, const void *dadd) 2948 { 2949 Rel_copy rc; 2950 Lm_list *lml = LIST(rlmp); 2951 2952 rc.r_name = name; 2953 rc.r_rsym = rsym; /* the new reference symbol and its */ 2954 rc.r_rlmp = rlmp; /* associated link-map */ 2955 rc.r_dlmp = dlmp; /* the defining link-map */ 2956 rc.r_dsym = dsym; /* the original definition */ 2957 rc.r_radd = radd; 2958 rc.r_dadd = dadd; 2959 2960 if (rsym->st_size > dsym->st_size) 2961 rc.r_size = (size_t)dsym->st_size; 2962 else 2963 rc.r_size = (size_t)rsym->st_size; 2964 2965 if (alist_append(©(dlmp), &rc, sizeof (Rel_copy), 2966 AL_CNT_COPYREL) == 0) { 2967 if (!(lml->lm_flags & LML_FLG_TRC_WARN)) 2968 return (0); 2969 else 2970 return (1); 2971 } 2972 if (!(FLAGS1(dlmp) & FL1_RT_COPYTOOK)) { 2973 if (alist_append(©(rlmp), &dlmp, 2974 sizeof (Rt_map *), AL_CNT_COPYREL) == 0) { 2975 if (!(lml->lm_flags & LML_FLG_TRC_WARN)) 2976 return (0); 2977 else 2978 return (1); 2979 } 2980 FLAGS1(dlmp) |= FL1_RT_COPYTOOK; 2981 } 2982 2983 /* 2984 * If we are tracing (ldd), warn the user if 2985 * 1) the size from the reference symbol differs from the 2986 * copy definition. We can only copy as much data as the 2987 * reference (dynamic executables) entry allows. 2988 * 2) the copy definition has STV_PROTECTED visibility. 2989 */ 2990 if (lml->lm_flags & LML_FLG_TRC_WARN) { 2991 if (rsym->st_size != dsym->st_size) { 2992 (void) printf(MSG_INTL(MSG_LDD_CPY_SIZDIF), 2993 _conv_reloc_type(M_R_COPY), demangle(name), 2994 NAME(rlmp), EC_XWORD(rsym->st_size), 2995 NAME(dlmp), EC_XWORD(dsym->st_size)); 2996 if (rsym->st_size > dsym->st_size) 2997 (void) printf(MSG_INTL(MSG_LDD_CPY_INSDATA), 2998 NAME(dlmp)); 2999 else 3000 (void) printf(MSG_INTL(MSG_LDD_CPY_DATRUNC), 3001 NAME(rlmp)); 3002 } 3003 3004 if (ELF_ST_VISIBILITY(dsym->st_other) == STV_PROTECTED) { 3005 (void) printf(MSG_INTL(MSG_LDD_CPY_PROT), 3006 _conv_reloc_type(M_R_COPY), demangle(name), 3007 NAME(dlmp)); 3008 } 3009 } 3010 3011 DBG_CALL(Dbg_reloc_apply_val(lml, ELF_DBG_RTLD, (Xword)radd, 3012 (Xword)rc.r_size)); 3013 return (1); 3014 } 3015 3016 /* 3017 * Determine the symbol location of an address within a link-map. Look for 3018 * the nearest symbol (whose value is less than or equal to the required 3019 * address). This is the object specific part of dladdr(). 3020 */ 3021 static void 3022 elf_dladdr(ulong_t addr, Rt_map *lmp, Dl_info *dlip, void **info, int flags) 3023 { 3024 ulong_t ndx, cnt, base, _value; 3025 Sym *sym, *_sym = NULL; 3026 const char *str; 3027 int _flags; 3028 uint_t *dynaddr_ndx; 3029 uint_t dynaddr_n = 0; 3030 ulong_t value; 3031 3032 /* 3033 * If SUNWSYMTAB() is non-NULL, then it sees a special version of 3034 * the dynsym that starts with any local function symbols that exist in 3035 * the library and then moves to the data held in SYMTAB(). In this 3036 * case, SUNWSYMSZ tells us how long the symbol table is. The 3037 * availability of local function symbols will enhance the results 3038 * we can provide. 3039 * 3040 * If SUNWSYMTAB() is non-NULL, then there might also be a 3041 * SUNWSYMSORT() vector associated with it. SUNWSYMSORT() contains 3042 * an array of indices into SUNWSYMTAB, sorted by increasing 3043 * address. We can use this to do an O(log N) search instead of a 3044 * brute force search. 3045 * 3046 * If SUNWSYMTAB() is NULL, then SYMTAB() references a dynsym that 3047 * contains only global symbols. In that case, the length of 3048 * the symbol table comes from the nchain field of the related 3049 * symbol lookup hash table. 3050 */ 3051 str = STRTAB(lmp); 3052 if (SUNWSYMSZ(lmp) == NULL) { 3053 sym = SYMTAB(lmp); 3054 /* 3055 * If we don't have a .hash table there are no symbols 3056 * to look at. 3057 */ 3058 if (HASH(lmp) == 0) 3059 return; 3060 cnt = HASH(lmp)[1]; 3061 } else { 3062 sym = SUNWSYMTAB(lmp); 3063 cnt = SUNWSYMSZ(lmp) / SYMENT(lmp); 3064 dynaddr_ndx = SUNWSYMSORT(lmp); 3065 if (dynaddr_ndx != NULL) 3066 dynaddr_n = SUNWSYMSORTSZ(lmp) / SUNWSORTENT(lmp); 3067 } 3068 3069 if (FLAGS(lmp) & FLG_RT_FIXED) 3070 base = 0; 3071 else 3072 base = ADDR(lmp); 3073 3074 if (dynaddr_n > 0) { /* Binary search */ 3075 long low = 0, low_bnd; 3076 long high = dynaddr_n - 1, high_bnd; 3077 long mid; 3078 Sym *mid_sym; 3079 3080 /* 3081 * Note that SUNWSYMSORT only contains symbols types that 3082 * supply memory addresses, so there's no need to check and 3083 * filter out any other types. 3084 */ 3085 low_bnd = low; 3086 high_bnd = high; 3087 while (low <= high) { 3088 mid = (low + high) / 2; 3089 mid_sym = &sym[dynaddr_ndx[mid]]; 3090 value = mid_sym->st_value + base; 3091 if (addr < value) { 3092 if ((sym[dynaddr_ndx[high]].st_value + base) >= 3093 addr) 3094 high_bnd = high; 3095 high = mid - 1; 3096 } else if (addr > value) { 3097 if ((sym[dynaddr_ndx[low]].st_value + base) <= 3098 addr) 3099 low_bnd = low; 3100 low = mid + 1; 3101 } else { 3102 _sym = mid_sym; 3103 _value = value; 3104 break; 3105 } 3106 } 3107 /* 3108 * If the above didn't find it exactly, then we must 3109 * return the closest symbol with a value that doesn't 3110 * exceed the one we are looking for. If that symbol exists, 3111 * it will lie in the range bounded by low_bnd and 3112 * high_bnd. This is a linear search, but a short one. 3113 */ 3114 if (_sym == NULL) { 3115 for (mid = low_bnd; mid <= high_bnd; mid++) { 3116 mid_sym = &sym[dynaddr_ndx[mid]]; 3117 value = mid_sym->st_value + base; 3118 if (addr >= value) { 3119 _sym = mid_sym; 3120 _value = value; 3121 } else { 3122 break; 3123 } 3124 } 3125 } 3126 } else { /* Linear search */ 3127 for (_value = 0, sym++, ndx = 1; ndx < cnt; ndx++, sym++) { 3128 /* 3129 * Skip expected symbol types that are not functions 3130 * or data: 3131 * - A symbol table starts with an undefined symbol 3132 * in slot 0. If we are using SUNWSYMTAB(), 3133 * there will be a second undefined symbol 3134 * right before the globals. 3135 * - The local part of SUNWSYMTAB() contains a 3136 * series of function symbols. Each section 3137 * starts with an initial STT_FILE symbol. 3138 */ 3139 if ((sym->st_shndx == SHN_UNDEF) || 3140 (ELF_ST_TYPE(sym->st_info) == STT_FILE)) 3141 continue; 3142 3143 value = sym->st_value + base; 3144 if (value > addr) 3145 continue; 3146 if (value < _value) 3147 continue; 3148 3149 _sym = sym; 3150 _value = value; 3151 3152 /* 3153 * Note, because we accept local and global symbols 3154 * we could find a section symbol that matches the 3155 * associated address, which means that the symbol 3156 * name will be null. In this case continue the 3157 * search in case we can find a global symbol of 3158 * the same value. 3159 */ 3160 if ((value == addr) && 3161 (ELF_ST_TYPE(sym->st_info) != STT_SECTION)) 3162 break; 3163 } 3164 } 3165 3166 _flags = flags & RTLD_DL_MASK; 3167 if (_sym) { 3168 if (_flags == RTLD_DL_SYMENT) 3169 *info = (void *)_sym; 3170 else if (_flags == RTLD_DL_LINKMAP) 3171 *info = (void *)lmp; 3172 3173 dlip->dli_sname = str + _sym->st_name; 3174 dlip->dli_saddr = (void *)_value; 3175 } else { 3176 /* 3177 * addr lies between the beginning of the mapped segment and 3178 * the first global symbol. We have no symbol to return 3179 * and the caller requires one. We use _START_, the base 3180 * address of the mapping. 3181 */ 3182 3183 if (_flags == RTLD_DL_SYMENT) { 3184 /* 3185 * An actual symbol struct is needed, so we 3186 * construct one for _START_. To do this in a 3187 * fully accurate way requires a different symbol 3188 * for each mapped segment. This requires the 3189 * use of dynamic memory and a mutex. That's too much 3190 * plumbing for a fringe case of limited importance. 3191 * 3192 * Fortunately, we can simplify: 3193 * - Only the st_size and st_info fields are useful 3194 * outside of the linker internals. The others 3195 * reference things that outside code cannot see, 3196 * and can be set to 0. 3197 * - It's just a label and there is no size 3198 * to report. So, the size should be 0. 3199 * This means that only st_info needs a non-zero 3200 * (constant) value. A static struct will suffice. 3201 * It must be const (readonly) so the caller can't 3202 * change its meaning for subsequent callers. 3203 */ 3204 static const Sym fsym = { 0, 0, 0, 3205 ELF_ST_INFO(STB_LOCAL, STT_OBJECT) }; 3206 *info = (void *) &fsym; 3207 } 3208 3209 dlip->dli_sname = MSG_ORIG(MSG_SYM_START); 3210 dlip->dli_saddr = (void *) ADDR(lmp); 3211 } 3212 } 3213 3214 static void 3215 elf_lazy_cleanup(Alist *alp) 3216 { 3217 Rt_map **lmpp; 3218 Aliste off; 3219 3220 /* 3221 * Cleanup any link-maps added to this dynamic list and free it. 3222 */ 3223 for (ALIST_TRAVERSE(alp, off, lmpp)) 3224 FLAGS(*lmpp) &= ~FLG_RT_DLSYM; 3225 free(alp); 3226 } 3227 3228 /* 3229 * This routine is called upon to search for a symbol from the dependencies of 3230 * the initial link-map. To maintain lazy loadings goal of reducing the number 3231 * of objects mapped, any symbol search is first carried out using the objects 3232 * that already exist in the process (either on a link-map list or handle). 3233 * If a symbol can't be found, and lazy dependencies are still pending, this 3234 * routine loads the dependencies in an attempt to locate the symbol. 3235 * 3236 * Only new objects are inspected as we will have already inspected presently 3237 * loaded objects before calling this routine. However, a new object may not 3238 * be new - although the di_lmp might be zero, the object may have been mapped 3239 * as someone elses dependency. Thus there's a possibility of some symbol 3240 * search duplication. 3241 */ 3242 3243 Sym * 3244 elf_lazy_find_sym(Slookup *slp, Rt_map **_lmp, uint_t *binfo) 3245 { 3246 Sym *sym = 0; 3247 Alist * alist = 0; 3248 Aliste off; 3249 Rt_map ** lmpp, * lmp = slp->sl_imap; 3250 const char *name = slp->sl_name; 3251 3252 if (alist_append(&alist, &lmp, sizeof (Rt_map *), AL_CNT_LAZYFIND) == 0) 3253 return (0); 3254 FLAGS(lmp) |= FLG_RT_DLSYM; 3255 3256 for (ALIST_TRAVERSE(alist, off, lmpp)) { 3257 uint_t cnt = 0; 3258 Slookup sl = *slp; 3259 Dyninfo *dip; 3260 3261 /* 3262 * Loop through the DT_NEEDED entries examining each object for 3263 * the symbol. If the symbol is not found the object is in turn 3264 * added to the alist, so that its DT_NEEDED entires may be 3265 * examined. 3266 */ 3267 lmp = *lmpp; 3268 for (dip = DYNINFO(lmp); cnt < DYNINFOCNT(lmp); cnt++, dip++) { 3269 Rt_map *nlmp; 3270 3271 if (((dip->di_flags & FLG_DI_NEEDED) == 0) || 3272 dip->di_info) 3273 continue; 3274 3275 /* 3276 * If this entry defines a lazy dependency try loading 3277 * it. If the file can't be loaded, consider this 3278 * non-fatal and continue the search (lazy loaded 3279 * dependencies need not exist and their loading should 3280 * only be fatal if called from a relocation). 3281 * 3282 * If the file is already loaded and relocated we must 3283 * still inspect it for symbols, even though it might 3284 * have already been searched. This lazy load operation 3285 * might have promoted the permissions of the object, 3286 * and thus made the object applicable for this symbol 3287 * search, whereas before the object might have been 3288 * skipped. 3289 */ 3290 if ((nlmp = elf_lazy_load(lmp, cnt, name)) == 0) 3291 continue; 3292 3293 /* 3294 * If this object isn't yet a part of the dynamic list 3295 * then inspect it for the symbol. If the symbol isn't 3296 * found add the object to the dynamic list so that we 3297 * can inspect its dependencies. 3298 */ 3299 if (FLAGS(nlmp) & FLG_RT_DLSYM) 3300 continue; 3301 3302 sl.sl_imap = nlmp; 3303 if (sym = LM_LOOKUP_SYM(sl.sl_cmap)(&sl, _lmp, binfo)) 3304 break; 3305 3306 /* 3307 * Some dlsym() operations are already traversing a 3308 * link-map (dlopen(0)), and thus there's no need to 3309 * build our own dynamic dependency list. 3310 */ 3311 if ((sl.sl_flags & LKUP_NODESCENT) == 0) { 3312 if (alist_append(&alist, &nlmp, 3313 sizeof (Rt_map *), AL_CNT_LAZYFIND) == 0) { 3314 elf_lazy_cleanup(alist); 3315 return (0); 3316 } 3317 FLAGS(nlmp) |= FLG_RT_DLSYM; 3318 } 3319 } 3320 if (sym) 3321 break; 3322 } 3323 3324 elf_lazy_cleanup(alist); 3325 return (sym); 3326 } 3327 3328 /* 3329 * Warning message for bad r_offset. 3330 */ 3331 void 3332 elf_reloc_bad(Rt_map *lmp, void *rel, uchar_t rtype, ulong_t roffset, 3333 ulong_t rsymndx) 3334 { 3335 const char *name = (char *)0; 3336 Lm_list *lml = LIST(lmp); 3337 int trace; 3338 3339 if ((lml->lm_flags & LML_FLG_TRC_ENABLE) && 3340 (((rtld_flags & RT_FL_SILENCERR) == 0) || 3341 (lml->lm_flags & LML_FLG_TRC_VERBOSE))) 3342 trace = 1; 3343 else 3344 trace = 0; 3345 3346 if ((trace == 0) && (DBG_ENABLED == 0)) 3347 return; 3348 3349 if (rsymndx) { 3350 Sym *symref = (Sym *)((ulong_t)SYMTAB(lmp) + 3351 (rsymndx * SYMENT(lmp))); 3352 3353 if (ELF_ST_BIND(symref->st_info) != STB_LOCAL) 3354 name = (char *)(STRTAB(lmp) + symref->st_name); 3355 } 3356 3357 if (name == 0) 3358 name = MSG_ORIG(MSG_STR_EMPTY); 3359 3360 if (trace) { 3361 const char *rstr; 3362 3363 rstr = _conv_reloc_type((uint_t)rtype); 3364 (void) printf(MSG_INTL(MSG_LDD_REL_ERR1), rstr, name, 3365 EC_ADDR(roffset)); 3366 return; 3367 } 3368 3369 Dbg_reloc_error(lml, ELF_DBG_RTLD, M_MACH, M_REL_SHT_TYPE, rel, name); 3370 } 3371 3372 /* 3373 * Resolve a static TLS relocation. 3374 */ 3375 long 3376 elf_static_tls(Rt_map *lmp, Sym *sym, void *rel, uchar_t rtype, char *name, 3377 ulong_t roffset, long value) 3378 { 3379 Lm_list *lml = LIST(lmp); 3380 3381 /* 3382 * Relocations against a static TLS block have limited support once 3383 * process initialization has completed. Any error condition should be 3384 * discovered by testing for DF_STATIC_TLS as part of loading an object, 3385 * however individual relocations are tested in case the dynamic flag 3386 * had not been set when this object was built. 3387 */ 3388 if (PTTLS(lmp) == 0) { 3389 DBG_CALL(Dbg_reloc_in(lml, ELF_DBG_RTLD, M_MACH, 3390 M_REL_SHT_TYPE, rel, NULL, name)); 3391 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_REL_BADTLS), 3392 _conv_reloc_type((uint_t)rtype), NAME(lmp), 3393 name ? demangle(name) : MSG_INTL(MSG_STR_UNKNOWN)); 3394 return (0); 3395 } 3396 3397 /* 3398 * If no static TLS has been set aside for this object, determine if 3399 * any can be obtained. Enforce that any object using static TLS is 3400 * non-deletable. 3401 */ 3402 if (TLSSTATOFF(lmp) == 0) { 3403 FLAGS1(lmp) |= FL1_RT_TLSSTAT; 3404 MODE(lmp) |= RTLD_NODELETE; 3405 3406 if (tls_assign(lml, lmp, PTTLS(lmp)) == 0) { 3407 DBG_CALL(Dbg_reloc_in(lml, ELF_DBG_RTLD, M_MACH, 3408 M_REL_SHT_TYPE, rel, NULL, name)); 3409 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_REL_BADTLS), 3410 _conv_reloc_type((uint_t)rtype), NAME(lmp), 3411 name ? demangle(name) : MSG_INTL(MSG_STR_UNKNOWN)); 3412 return (0); 3413 } 3414 } 3415 3416 /* 3417 * Typically, a static TLS offset is maintained as a symbols value. 3418 * For local symbols that are not apart of the dynamic symbol table, 3419 * the TLS relocation points to a section symbol, and the static TLS 3420 * offset was deposited in the associated GOT table. Make sure the GOT 3421 * is cleared, so that the value isn't reused in do_reloc(). 3422 */ 3423 if (ELF_ST_BIND(sym->st_info) == STB_LOCAL) { 3424 if ((ELF_ST_TYPE(sym->st_info) == STT_SECTION)) { 3425 value = *(long *)roffset; 3426 *(long *)roffset = 0; 3427 } else { 3428 value = sym->st_value; 3429 } 3430 } 3431 return (-(TLSSTATOFF(lmp) - value)); 3432 } 3433