The Design and Implementation of the FreeBSD Operating System, Second Edition
Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)


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FreeBSD/Linux Kernel Cross Reference
sys/kern/link_elf_obj.c

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    1 /*-
    2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
    3  *
    4  * Copyright (c) 1998-2000 Doug Rabson
    5  * Copyright (c) 2004 Peter Wemm
    6  * All rights reserved.
    7  *
    8  * Redistribution and use in source and binary forms, with or without
    9  * modification, are permitted provided that the following conditions
   10  * are met:
   11  * 1. Redistributions of source code must retain the above copyright
   12  *    notice, this list of conditions and the following disclaimer.
   13  * 2. Redistributions in binary form must reproduce the above copyright
   14  *    notice, this list of conditions and the following disclaimer in the
   15  *    documentation and/or other materials provided with the distribution.
   16  *
   17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
   18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
   21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   27  * SUCH DAMAGE.
   28  */
   29 
   30 #include <sys/cdefs.h>
   31 __FBSDID("$FreeBSD$");
   32 
   33 #include "opt_ddb.h"
   34 
   35 #include <sys/param.h>
   36 #include <sys/systm.h>
   37 #include <sys/fcntl.h>
   38 #include <sys/kernel.h>
   39 #include <sys/lock.h>
   40 #include <sys/malloc.h>
   41 #include <sys/linker.h>
   42 #include <sys/mutex.h>
   43 #include <sys/mount.h>
   44 #include <sys/namei.h>
   45 #include <sys/proc.h>
   46 #include <sys/rwlock.h>
   47 #include <sys/sysctl.h>
   48 #include <sys/vnode.h>
   49 
   50 #include <machine/elf.h>
   51 
   52 #include <net/vnet.h>
   53 
   54 #include <security/mac/mac_framework.h>
   55 
   56 #include <vm/vm.h>
   57 #include <vm/vm_param.h>
   58 #include <vm/pmap.h>
   59 #include <vm/vm_extern.h>
   60 #include <vm/vm_kern.h>
   61 #include <vm/vm_map.h>
   62 #include <vm/vm_object.h>
   63 #include <vm/vm_page.h>
   64 #include <vm/vm_pager.h>
   65 
   66 #include <sys/link_elf.h>
   67 
   68 #ifdef DDB_CTF
   69 #include <contrib/zlib/zlib.h>
   70 #endif
   71 
   72 #include "linker_if.h"
   73 
   74 typedef struct {
   75         void            *addr;
   76         Elf_Off         size;
   77         int             flags;  /* Section flags. */
   78         int             sec;    /* Original section number. */
   79         char            *name;
   80 } Elf_progent;
   81 
   82 typedef struct {
   83         Elf_Rel         *rel;
   84         int             nrel;
   85         int             sec;
   86 } Elf_relent;
   87 
   88 typedef struct {
   89         Elf_Rela        *rela;
   90         int             nrela;
   91         int             sec;
   92 } Elf_relaent;
   93 
   94 typedef struct elf_file {
   95         struct linker_file lf;          /* Common fields */
   96 
   97         int             preloaded;
   98         caddr_t         address;        /* Relocation address */
   99         vm_object_t     object;         /* VM object to hold file pages */
  100         Elf_Shdr        *e_shdr;
  101 
  102         Elf_progent     *progtab;
  103         u_int           nprogtab;
  104 
  105         Elf_relaent     *relatab;
  106         u_int           nrelatab;
  107 
  108         Elf_relent      *reltab;
  109         int             nreltab;
  110 
  111         Elf_Sym         *ddbsymtab;     /* The symbol table we are using */
  112         long            ddbsymcnt;      /* Number of symbols */
  113         caddr_t         ddbstrtab;      /* String table */
  114         long            ddbstrcnt;      /* number of bytes in string table */
  115 
  116         caddr_t         shstrtab;       /* Section name string table */
  117         long            shstrcnt;       /* number of bytes in string table */
  118 
  119         caddr_t         ctftab;         /* CTF table */
  120         long            ctfcnt;         /* number of bytes in CTF table */
  121         caddr_t         ctfoff;         /* CTF offset table */
  122         caddr_t         typoff;         /* Type offset table */
  123         long            typlen;         /* Number of type entries. */
  124 
  125 } *elf_file_t;
  126 
  127 #include <kern/kern_ctf.c>
  128 
  129 static int      link_elf_link_preload(linker_class_t cls,
  130                     const char *, linker_file_t *);
  131 static int      link_elf_link_preload_finish(linker_file_t);
  132 static int      link_elf_load_file(linker_class_t, const char *, linker_file_t *);
  133 static int      link_elf_lookup_symbol(linker_file_t, const char *,
  134                     c_linker_sym_t *);
  135 static int      link_elf_lookup_debug_symbol(linker_file_t, const char *,
  136                     c_linker_sym_t *);
  137 static int      link_elf_symbol_values(linker_file_t, c_linker_sym_t,
  138                     linker_symval_t *);
  139 static int      link_elf_debug_symbol_values(linker_file_t, c_linker_sym_t,
  140                     linker_symval_t *);
  141 static int      link_elf_search_symbol(linker_file_t, caddr_t value,
  142                     c_linker_sym_t *sym, long *diffp);
  143 
  144 static void     link_elf_unload_file(linker_file_t);
  145 static int      link_elf_lookup_set(linker_file_t, const char *,
  146                     void ***, void ***, int *);
  147 static int      link_elf_each_function_name(linker_file_t,
  148                     int (*)(const char *, void *), void *);
  149 static int      link_elf_each_function_nameval(linker_file_t,
  150                                 linker_function_nameval_callback_t,
  151                                 void *);
  152 static int      link_elf_reloc_local(linker_file_t, bool);
  153 static long     link_elf_symtab_get(linker_file_t, const Elf_Sym **);
  154 static long     link_elf_strtab_get(linker_file_t, caddr_t *);
  155 
  156 static int      elf_obj_lookup(linker_file_t lf, Elf_Size symidx, int deps,
  157                     Elf_Addr *);
  158 
  159 static kobj_method_t link_elf_methods[] = {
  160         KOBJMETHOD(linker_lookup_symbol,        link_elf_lookup_symbol),
  161         KOBJMETHOD(linker_lookup_debug_symbol,  link_elf_lookup_debug_symbol),
  162         KOBJMETHOD(linker_symbol_values,        link_elf_symbol_values),
  163         KOBJMETHOD(linker_debug_symbol_values,  link_elf_debug_symbol_values),
  164         KOBJMETHOD(linker_search_symbol,        link_elf_search_symbol),
  165         KOBJMETHOD(linker_unload,               link_elf_unload_file),
  166         KOBJMETHOD(linker_load_file,            link_elf_load_file),
  167         KOBJMETHOD(linker_link_preload,         link_elf_link_preload),
  168         KOBJMETHOD(linker_link_preload_finish,  link_elf_link_preload_finish),
  169         KOBJMETHOD(linker_lookup_set,           link_elf_lookup_set),
  170         KOBJMETHOD(linker_each_function_name,   link_elf_each_function_name),
  171         KOBJMETHOD(linker_each_function_nameval, link_elf_each_function_nameval),
  172         KOBJMETHOD(linker_ctf_get,              link_elf_ctf_get),
  173         KOBJMETHOD(linker_symtab_get,           link_elf_symtab_get),
  174         KOBJMETHOD(linker_strtab_get,           link_elf_strtab_get),
  175         KOBJMETHOD_END
  176 };
  177 
  178 static struct linker_class link_elf_class = {
  179 #if ELF_TARG_CLASS == ELFCLASS32
  180         "elf32_obj",
  181 #else
  182         "elf64_obj",
  183 #endif
  184         link_elf_methods, sizeof(struct elf_file)
  185 };
  186 
  187 static bool link_elf_obj_leak_locals = true;
  188 SYSCTL_BOOL(_debug, OID_AUTO, link_elf_obj_leak_locals,
  189     CTLFLAG_RWTUN, &link_elf_obj_leak_locals, 0,
  190     "Allow local symbols to participate in global module symbol resolution");
  191 
  192 static int      relocate_file(elf_file_t ef);
  193 static void     elf_obj_cleanup_globals_cache(elf_file_t);
  194 
  195 static void
  196 link_elf_error(const char *filename, const char *s)
  197 {
  198         if (filename == NULL)
  199                 printf("kldload: %s\n", s);
  200         else
  201                 printf("kldload: %s: %s\n", filename, s);
  202 }
  203 
  204 static void
  205 link_elf_init(void *arg)
  206 {
  207 
  208         linker_add_class(&link_elf_class);
  209 }
  210 SYSINIT(link_elf_obj, SI_SUB_KLD, SI_ORDER_SECOND, link_elf_init, NULL);
  211 
  212 static void
  213 link_elf_protect_range(elf_file_t ef, vm_offset_t start, vm_offset_t end,
  214     vm_prot_t prot)
  215 {
  216         int error __unused;
  217 
  218         KASSERT(start <= end && start >= (vm_offset_t)ef->address &&
  219             end <= round_page((vm_offset_t)ef->address + ef->lf.size),
  220             ("link_elf_protect_range: invalid range %#jx-%#jx",
  221             (uintmax_t)start, (uintmax_t)end));
  222 
  223         if (start == end)
  224                 return;
  225         if (ef->preloaded) {
  226 #ifdef __amd64__
  227                 error = pmap_change_prot(start, end - start, prot);
  228                 KASSERT(error == 0,
  229                     ("link_elf_protect_range: pmap_change_prot() returned %d",
  230                     error));
  231 #endif
  232                 return;
  233         }
  234         error = vm_map_protect(kernel_map, start, end, prot, 0,
  235             VM_MAP_PROTECT_SET_PROT);
  236         KASSERT(error == KERN_SUCCESS,
  237             ("link_elf_protect_range: vm_map_protect() returned %d", error));
  238 }
  239 
  240 /*
  241  * Restrict permissions on linker file memory based on section flags.
  242  * Sections need not be page-aligned, so overlap within a page is possible.
  243  */
  244 static void
  245 link_elf_protect(elf_file_t ef)
  246 {
  247         vm_offset_t end, segend, segstart, start;
  248         vm_prot_t gapprot, prot, segprot;
  249         int i;
  250 
  251         /*
  252          * If the file was preloaded, the last page may contain other preloaded
  253          * data which may need to be writeable.  ELF files are always
  254          * page-aligned, but other preloaded data, such as entropy or CPU
  255          * microcode may be loaded with a smaller alignment.
  256          */
  257         gapprot = ef->preloaded ? VM_PROT_RW : VM_PROT_READ;
  258 
  259         start = end = (vm_offset_t)ef->address;
  260         prot = VM_PROT_READ;
  261         for (i = 0; i < ef->nprogtab; i++) {
  262                 /*
  263                  * VNET and DPCPU sections have their memory allocated by their
  264                  * respective subsystems.
  265                  */
  266                 if (ef->progtab[i].name != NULL && (
  267 #ifdef VIMAGE
  268                     strcmp(ef->progtab[i].name, VNET_SETNAME) == 0 ||
  269 #endif
  270                     strcmp(ef->progtab[i].name, DPCPU_SETNAME) == 0))
  271                         continue;
  272 
  273                 segstart = trunc_page((vm_offset_t)ef->progtab[i].addr);
  274                 segend = round_page((vm_offset_t)ef->progtab[i].addr +
  275                     ef->progtab[i].size);
  276                 segprot = VM_PROT_READ;
  277                 if ((ef->progtab[i].flags & SHF_WRITE) != 0)
  278                         segprot |= VM_PROT_WRITE;
  279                 if ((ef->progtab[i].flags & SHF_EXECINSTR) != 0)
  280                         segprot |= VM_PROT_EXECUTE;
  281 
  282                 if (end <= segstart) {
  283                         /*
  284                          * Case 1: there is no overlap between the previous
  285                          * segment and this one.  Apply protections to the
  286                          * previous segment, and protect the gap between the
  287                          * previous and current segments, if any.
  288                          */
  289                         link_elf_protect_range(ef, start, end, prot);
  290                         link_elf_protect_range(ef, end, segstart, gapprot);
  291 
  292                         start = segstart;
  293                         end = segend;
  294                         prot = segprot;
  295                 } else if (start < segstart && end == segend) {
  296                         /*
  297                          * Case 2: the current segment is a subrange of the
  298                          * previous segment.  Apply protections to the
  299                          * non-overlapping portion of the previous segment.
  300                          */
  301                         link_elf_protect_range(ef, start, segstart, prot);
  302 
  303                         start = segstart;
  304                         prot |= segprot;
  305                 } else if (end < segend) {
  306                         /*
  307                          * Case 3: there is partial overlap between the previous
  308                          * and current segments.  Apply protections to the
  309                          * non-overlapping portion of the previous segment, and
  310                          * then the overlap, which must use the union of the two
  311                          * segments' protections.
  312                          */
  313                         link_elf_protect_range(ef, start, segstart, prot);
  314                         link_elf_protect_range(ef, segstart, end,
  315                             prot | segprot);
  316                         start = end;
  317                         end = segend;
  318                         prot = segprot;
  319                 } else {
  320                         /*
  321                          * Case 4: the two segments reside in the same page.
  322                          */
  323                         prot |= segprot;
  324                 }
  325         }
  326 
  327         /*
  328          * Fix up the last unprotected segment and trailing data.
  329          */
  330         link_elf_protect_range(ef, start, end, prot);
  331         link_elf_protect_range(ef, end,
  332             round_page((vm_offset_t)ef->address + ef->lf.size), gapprot);
  333 }
  334 
  335 static int
  336 link_elf_link_preload(linker_class_t cls, const char *filename,
  337     linker_file_t *result)
  338 {
  339         Elf_Ehdr *hdr;
  340         Elf_Shdr *shdr;
  341         Elf_Sym *es;
  342         void *modptr, *baseptr, *sizeptr;
  343         char *type;
  344         elf_file_t ef;
  345         linker_file_t lf;
  346         Elf_Addr off;
  347         int error, i, j, pb, ra, rl, shstrindex, symstrindex, symtabindex;
  348 
  349         /* Look to see if we have the file preloaded */
  350         modptr = preload_search_by_name(filename);
  351         if (modptr == NULL)
  352                 return ENOENT;
  353 
  354         type = (char *)preload_search_info(modptr, MODINFO_TYPE);
  355         baseptr = preload_search_info(modptr, MODINFO_ADDR);
  356         sizeptr = preload_search_info(modptr, MODINFO_SIZE);
  357         hdr = (Elf_Ehdr *)preload_search_info(modptr, MODINFO_METADATA |
  358             MODINFOMD_ELFHDR);
  359         shdr = (Elf_Shdr *)preload_search_info(modptr, MODINFO_METADATA |
  360             MODINFOMD_SHDR);
  361         if (type == NULL || (strcmp(type, "elf" __XSTRING(__ELF_WORD_SIZE)
  362             " obj module") != 0 &&
  363             strcmp(type, "elf obj module") != 0)) {
  364                 return (EFTYPE);
  365         }
  366         if (baseptr == NULL || sizeptr == NULL || hdr == NULL ||
  367             shdr == NULL)
  368                 return (EINVAL);
  369 
  370         lf = linker_make_file(filename, &link_elf_class);
  371         if (lf == NULL)
  372                 return (ENOMEM);
  373 
  374         ef = (elf_file_t)lf;
  375         ef->preloaded = 1;
  376         ef->address = *(caddr_t *)baseptr;
  377         lf->address = *(caddr_t *)baseptr;
  378         lf->size = *(size_t *)sizeptr;
  379 
  380         if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS ||
  381             hdr->e_ident[EI_DATA] != ELF_TARG_DATA ||
  382             hdr->e_ident[EI_VERSION] != EV_CURRENT ||
  383             hdr->e_version != EV_CURRENT ||
  384             hdr->e_type != ET_REL ||
  385             hdr->e_machine != ELF_TARG_MACH) {
  386                 error = EFTYPE;
  387                 goto out;
  388         }
  389         ef->e_shdr = shdr;
  390 
  391         /* Scan the section header for information and table sizing. */
  392         symtabindex = -1;
  393         symstrindex = -1;
  394         for (i = 0; i < hdr->e_shnum; i++) {
  395                 switch (shdr[i].sh_type) {
  396                 case SHT_PROGBITS:
  397                 case SHT_NOBITS:
  398 #ifdef __amd64__
  399                 case SHT_X86_64_UNWIND:
  400 #endif
  401                 case SHT_INIT_ARRAY:
  402                 case SHT_FINI_ARRAY:
  403                         /* Ignore sections not loaded by the loader. */
  404                         if (shdr[i].sh_addr == 0)
  405                                 break;
  406                         ef->nprogtab++;
  407                         break;
  408                 case SHT_SYMTAB:
  409                         symtabindex = i;
  410                         symstrindex = shdr[i].sh_link;
  411                         break;
  412                 case SHT_REL:
  413                         /*
  414                          * Ignore relocation tables for sections not
  415                          * loaded by the loader.
  416                          */
  417                         if (shdr[shdr[i].sh_info].sh_addr == 0)
  418                                 break;
  419                         ef->nreltab++;
  420                         break;
  421                 case SHT_RELA:
  422                         if (shdr[shdr[i].sh_info].sh_addr == 0)
  423                                 break;
  424                         ef->nrelatab++;
  425                         break;
  426                 }
  427         }
  428 
  429         shstrindex = hdr->e_shstrndx;
  430         if (ef->nprogtab == 0 || symstrindex < 0 ||
  431             symstrindex >= hdr->e_shnum ||
  432             shdr[symstrindex].sh_type != SHT_STRTAB || shstrindex == 0 ||
  433             shstrindex >= hdr->e_shnum ||
  434             shdr[shstrindex].sh_type != SHT_STRTAB) {
  435                 printf("%s: bad/missing section headers\n", filename);
  436                 error = ENOEXEC;
  437                 goto out;
  438         }
  439 
  440         /* Allocate space for tracking the load chunks */
  441         if (ef->nprogtab != 0)
  442                 ef->progtab = malloc(ef->nprogtab * sizeof(*ef->progtab),
  443                     M_LINKER, M_WAITOK | M_ZERO);
  444         if (ef->nreltab != 0)
  445                 ef->reltab = malloc(ef->nreltab * sizeof(*ef->reltab),
  446                     M_LINKER, M_WAITOK | M_ZERO);
  447         if (ef->nrelatab != 0)
  448                 ef->relatab = malloc(ef->nrelatab * sizeof(*ef->relatab),
  449                     M_LINKER, M_WAITOK | M_ZERO);
  450         if ((ef->nprogtab != 0 && ef->progtab == NULL) ||
  451             (ef->nreltab != 0 && ef->reltab == NULL) ||
  452             (ef->nrelatab != 0 && ef->relatab == NULL)) {
  453                 error = ENOMEM;
  454                 goto out;
  455         }
  456 
  457         /* XXX, relocate the sh_addr fields saved by the loader. */
  458         off = 0;
  459         for (i = 0; i < hdr->e_shnum; i++) {
  460                 if (shdr[i].sh_addr != 0 && (off == 0 || shdr[i].sh_addr < off))
  461                         off = shdr[i].sh_addr;
  462         }
  463         for (i = 0; i < hdr->e_shnum; i++) {
  464                 if (shdr[i].sh_addr != 0)
  465                         shdr[i].sh_addr = shdr[i].sh_addr - off +
  466                             (Elf_Addr)ef->address;
  467         }
  468 
  469         ef->ddbsymcnt = shdr[symtabindex].sh_size / sizeof(Elf_Sym);
  470         ef->ddbsymtab = (Elf_Sym *)shdr[symtabindex].sh_addr;
  471         ef->ddbstrcnt = shdr[symstrindex].sh_size;
  472         ef->ddbstrtab = (char *)shdr[symstrindex].sh_addr;
  473         ef->shstrcnt = shdr[shstrindex].sh_size;
  474         ef->shstrtab = (char *)shdr[shstrindex].sh_addr;
  475 
  476         /* Now fill out progtab and the relocation tables. */
  477         pb = 0;
  478         rl = 0;
  479         ra = 0;
  480         for (i = 0; i < hdr->e_shnum; i++) {
  481                 switch (shdr[i].sh_type) {
  482                 case SHT_PROGBITS:
  483                 case SHT_NOBITS:
  484 #ifdef __amd64__
  485                 case SHT_X86_64_UNWIND:
  486 #endif
  487                 case SHT_INIT_ARRAY:
  488                 case SHT_FINI_ARRAY:
  489                         if (shdr[i].sh_addr == 0)
  490                                 break;
  491                         ef->progtab[pb].addr = (void *)shdr[i].sh_addr;
  492                         if (shdr[i].sh_type == SHT_PROGBITS)
  493                                 ef->progtab[pb].name = "<<PROGBITS>>";
  494 #ifdef __amd64__
  495                         else if (shdr[i].sh_type == SHT_X86_64_UNWIND)
  496                                 ef->progtab[pb].name = "<<UNWIND>>";
  497 #endif
  498                         else if (shdr[i].sh_type == SHT_INIT_ARRAY)
  499                                 ef->progtab[pb].name = "<<INIT_ARRAY>>";
  500                         else if (shdr[i].sh_type == SHT_FINI_ARRAY)
  501                                 ef->progtab[pb].name = "<<FINI_ARRAY>>";
  502                         else
  503                                 ef->progtab[pb].name = "<<NOBITS>>";
  504                         ef->progtab[pb].size = shdr[i].sh_size;
  505                         ef->progtab[pb].flags = shdr[i].sh_flags;
  506                         ef->progtab[pb].sec = i;
  507                         if (ef->shstrtab && shdr[i].sh_name != 0)
  508                                 ef->progtab[pb].name =
  509                                     ef->shstrtab + shdr[i].sh_name;
  510                         if (ef->progtab[pb].name != NULL && 
  511                             !strcmp(ef->progtab[pb].name, DPCPU_SETNAME)) {
  512                                 void *dpcpu;
  513 
  514                                 dpcpu = dpcpu_alloc(shdr[i].sh_size);
  515                                 if (dpcpu == NULL) {
  516                                         printf("%s: pcpu module space is out "
  517                                             "of space; cannot allocate %#jx "
  518                                             "for %s\n", __func__,
  519                                             (uintmax_t)shdr[i].sh_size,
  520                                             filename);
  521                                         error = ENOSPC;
  522                                         goto out;
  523                                 }
  524                                 memcpy(dpcpu, ef->progtab[pb].addr,
  525                                     ef->progtab[pb].size);
  526                                 dpcpu_copy(dpcpu, shdr[i].sh_size);
  527                                 ef->progtab[pb].addr = dpcpu;
  528 #ifdef VIMAGE
  529                         } else if (ef->progtab[pb].name != NULL &&
  530                             !strcmp(ef->progtab[pb].name, VNET_SETNAME)) {
  531                                 void *vnet_data;
  532 
  533                                 vnet_data = vnet_data_alloc(shdr[i].sh_size);
  534                                 if (vnet_data == NULL) {
  535                                         printf("%s: vnet module space is out "
  536                                             "of space; cannot allocate %#jx "
  537                                             "for %s\n", __func__,
  538                                             (uintmax_t)shdr[i].sh_size,
  539                                             filename);
  540                                         error = ENOSPC;
  541                                         goto out;
  542                                 }
  543                                 memcpy(vnet_data, ef->progtab[pb].addr,
  544                                     ef->progtab[pb].size);
  545                                 vnet_data_copy(vnet_data, shdr[i].sh_size);
  546                                 ef->progtab[pb].addr = vnet_data;
  547 #endif
  548                         } else if ((ef->progtab[pb].name != NULL &&
  549                             strcmp(ef->progtab[pb].name, ".ctors") == 0) ||
  550                             shdr[i].sh_type == SHT_INIT_ARRAY) {
  551                                 if (lf->ctors_addr != 0) {
  552                                         printf(
  553                                     "%s: multiple ctor sections in %s\n",
  554                                             __func__, filename);
  555                                 } else {
  556                                         lf->ctors_addr = ef->progtab[pb].addr;
  557                                         lf->ctors_size = shdr[i].sh_size;
  558                                 }
  559                         } else if ((ef->progtab[pb].name != NULL &&
  560                             strcmp(ef->progtab[pb].name, ".dtors") == 0) ||
  561                             shdr[i].sh_type == SHT_FINI_ARRAY) {
  562                                 if (lf->dtors_addr != 0) {
  563                                         printf(
  564                                     "%s: multiple dtor sections in %s\n",
  565                                             __func__, filename);
  566                                 } else {
  567                                         lf->dtors_addr = ef->progtab[pb].addr;
  568                                         lf->dtors_size = shdr[i].sh_size;
  569                                 }
  570                         }
  571 
  572                         /* Update all symbol values with the offset. */
  573                         for (j = 0; j < ef->ddbsymcnt; j++) {
  574                                 es = &ef->ddbsymtab[j];
  575                                 if (es->st_shndx != i)
  576                                         continue;
  577                                 es->st_value += (Elf_Addr)ef->progtab[pb].addr;
  578                         }
  579                         pb++;
  580                         break;
  581                 case SHT_REL:
  582                         if (shdr[shdr[i].sh_info].sh_addr == 0)
  583                                 break;
  584                         ef->reltab[rl].rel = (Elf_Rel *)shdr[i].sh_addr;
  585                         ef->reltab[rl].nrel = shdr[i].sh_size / sizeof(Elf_Rel);
  586                         ef->reltab[rl].sec = shdr[i].sh_info;
  587                         rl++;
  588                         break;
  589                 case SHT_RELA:
  590                         if (shdr[shdr[i].sh_info].sh_addr == 0)
  591                                 break;
  592                         ef->relatab[ra].rela = (Elf_Rela *)shdr[i].sh_addr;
  593                         ef->relatab[ra].nrela =
  594                             shdr[i].sh_size / sizeof(Elf_Rela);
  595                         ef->relatab[ra].sec = shdr[i].sh_info;
  596                         ra++;
  597                         break;
  598                 }
  599         }
  600         if (pb != ef->nprogtab) {
  601                 printf("%s: lost progbits\n", filename);
  602                 error = ENOEXEC;
  603                 goto out;
  604         }
  605         if (rl != ef->nreltab) {
  606                 printf("%s: lost reltab\n", filename);
  607                 error = ENOEXEC;
  608                 goto out;
  609         }
  610         if (ra != ef->nrelatab) {
  611                 printf("%s: lost relatab\n", filename);
  612                 error = ENOEXEC;
  613                 goto out;
  614         }
  615 
  616         /*
  617          * The file needs to be writeable and executable while applying
  618          * relocations.  Mapping protections are applied once relocation
  619          * processing is complete.
  620          */
  621         link_elf_protect_range(ef, (vm_offset_t)ef->address,
  622             round_page((vm_offset_t)ef->address + ef->lf.size), VM_PROT_ALL);
  623 
  624         /* Local intra-module relocations */
  625         error = link_elf_reloc_local(lf, false);
  626         if (error != 0)
  627                 goto out;
  628         *result = lf;
  629         return (0);
  630 
  631 out:
  632         /* preload not done this way */
  633         linker_file_unload(lf, LINKER_UNLOAD_FORCE);
  634         return (error);
  635 }
  636 
  637 static void
  638 link_elf_invoke_cbs(caddr_t addr, size_t size)
  639 {
  640         void (**ctor)(void);
  641         size_t i, cnt;
  642 
  643         if (addr == NULL || size == 0)
  644                 return;
  645         cnt = size / sizeof(*ctor);
  646         ctor = (void *)addr;
  647         for (i = 0; i < cnt; i++) {
  648                 if (ctor[i] != NULL)
  649                         (*ctor[i])();
  650         }
  651 }
  652 
  653 static int
  654 link_elf_link_preload_finish(linker_file_t lf)
  655 {
  656         elf_file_t ef;
  657         int error;
  658 
  659         ef = (elf_file_t)lf;
  660         error = relocate_file(ef);
  661         if (error)
  662                 return (error);
  663 
  664         /* Notify MD code that a module is being loaded. */
  665         error = elf_cpu_load_file(lf);
  666         if (error)
  667                 return (error);
  668 
  669 #if defined(__i386__) || defined(__amd64__)
  670         /* Now ifuncs. */
  671         error = link_elf_reloc_local(lf, true);
  672         if (error != 0)
  673                 return (error);
  674 #endif
  675 
  676         /* Apply protections now that relocation processing is complete. */
  677         link_elf_protect(ef);
  678 
  679         link_elf_invoke_cbs(lf->ctors_addr, lf->ctors_size);
  680         return (0);
  681 }
  682 
  683 static int
  684 link_elf_load_file(linker_class_t cls, const char *filename,
  685     linker_file_t *result)
  686 {
  687         struct nameidata *nd;
  688         struct thread *td = curthread;  /* XXX */
  689         Elf_Ehdr *hdr;
  690         Elf_Shdr *shdr;
  691         Elf_Sym *es;
  692         int nbytes, i, j;
  693         vm_offset_t mapbase;
  694         size_t mapsize;
  695         int error = 0;
  696         ssize_t resid;
  697         int flags;
  698         elf_file_t ef;
  699         linker_file_t lf;
  700         int symtabindex;
  701         int symstrindex;
  702         int shstrindex;
  703         int nsym;
  704         int pb, rl, ra;
  705         int alignmask;
  706 
  707         shdr = NULL;
  708         lf = NULL;
  709         mapsize = 0;
  710         hdr = NULL;
  711 
  712         nd = malloc(sizeof(struct nameidata), M_TEMP, M_WAITOK);
  713         NDINIT(nd, LOOKUP, FOLLOW, UIO_SYSSPACE, filename, td);
  714         flags = FREAD;
  715         error = vn_open(nd, &flags, 0, NULL);
  716         if (error) {
  717                 free(nd, M_TEMP);
  718                 return error;
  719         }
  720         NDFREE(nd, NDF_ONLY_PNBUF);
  721         if (nd->ni_vp->v_type != VREG) {
  722                 error = ENOEXEC;
  723                 goto out;
  724         }
  725 #ifdef MAC
  726         error = mac_kld_check_load(td->td_ucred, nd->ni_vp);
  727         if (error) {
  728                 goto out;
  729         }
  730 #endif
  731 
  732         /* Read the elf header from the file. */
  733         hdr = malloc(sizeof(*hdr), M_LINKER, M_WAITOK);
  734         error = vn_rdwr(UIO_READ, nd->ni_vp, (void *)hdr, sizeof(*hdr), 0,
  735             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
  736             &resid, td);
  737         if (error)
  738                 goto out;
  739         if (resid != 0){
  740                 error = ENOEXEC;
  741                 goto out;
  742         }
  743 
  744         if (!IS_ELF(*hdr)) {
  745                 error = ENOEXEC;
  746                 goto out;
  747         }
  748 
  749         if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS
  750             || hdr->e_ident[EI_DATA] != ELF_TARG_DATA) {
  751                 link_elf_error(filename, "Unsupported file layout");
  752                 error = ENOEXEC;
  753                 goto out;
  754         }
  755         if (hdr->e_ident[EI_VERSION] != EV_CURRENT
  756             || hdr->e_version != EV_CURRENT) {
  757                 link_elf_error(filename, "Unsupported file version");
  758                 error = ENOEXEC;
  759                 goto out;
  760         }
  761         if (hdr->e_type != ET_REL) {
  762                 error = ENOSYS;
  763                 goto out;
  764         }
  765         if (hdr->e_machine != ELF_TARG_MACH) {
  766                 link_elf_error(filename, "Unsupported machine");
  767                 error = ENOEXEC;
  768                 goto out;
  769         }
  770 
  771         lf = linker_make_file(filename, &link_elf_class);
  772         if (!lf) {
  773                 error = ENOMEM;
  774                 goto out;
  775         }
  776         ef = (elf_file_t) lf;
  777         ef->nprogtab = 0;
  778         ef->e_shdr = 0;
  779         ef->nreltab = 0;
  780         ef->nrelatab = 0;
  781 
  782         /* Allocate and read in the section header */
  783         nbytes = hdr->e_shnum * hdr->e_shentsize;
  784         if (nbytes == 0 || hdr->e_shoff == 0 ||
  785             hdr->e_shentsize != sizeof(Elf_Shdr)) {
  786                 error = ENOEXEC;
  787                 goto out;
  788         }
  789         shdr = malloc(nbytes, M_LINKER, M_WAITOK);
  790         ef->e_shdr = shdr;
  791         error = vn_rdwr(UIO_READ, nd->ni_vp, (caddr_t)shdr, nbytes,
  792             hdr->e_shoff, UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred,
  793             NOCRED, &resid, td);
  794         if (error)
  795                 goto out;
  796         if (resid) {
  797                 error = ENOEXEC;
  798                 goto out;
  799         }
  800 
  801         /* Scan the section header for information and table sizing. */
  802         nsym = 0;
  803         symtabindex = -1;
  804         symstrindex = -1;
  805         for (i = 0; i < hdr->e_shnum; i++) {
  806                 if (shdr[i].sh_size == 0)
  807                         continue;
  808                 switch (shdr[i].sh_type) {
  809                 case SHT_PROGBITS:
  810                 case SHT_NOBITS:
  811 #ifdef __amd64__
  812                 case SHT_X86_64_UNWIND:
  813 #endif
  814                 case SHT_INIT_ARRAY:
  815                 case SHT_FINI_ARRAY:
  816                         if ((shdr[i].sh_flags & SHF_ALLOC) == 0)
  817                                 break;
  818                         ef->nprogtab++;
  819                         break;
  820                 case SHT_SYMTAB:
  821                         nsym++;
  822                         symtabindex = i;
  823                         symstrindex = shdr[i].sh_link;
  824                         break;
  825                 case SHT_REL:
  826                         /*
  827                          * Ignore relocation tables for unallocated
  828                          * sections.
  829                          */
  830                         if ((shdr[shdr[i].sh_info].sh_flags & SHF_ALLOC) == 0)
  831                                 break;
  832                         ef->nreltab++;
  833                         break;
  834                 case SHT_RELA:
  835                         if ((shdr[shdr[i].sh_info].sh_flags & SHF_ALLOC) == 0)
  836                                 break;
  837                         ef->nrelatab++;
  838                         break;
  839                 case SHT_STRTAB:
  840                         break;
  841                 }
  842         }
  843         if (ef->nprogtab == 0) {
  844                 link_elf_error(filename, "file has no contents");
  845                 error = ENOEXEC;
  846                 goto out;
  847         }
  848         if (nsym != 1) {
  849                 /* Only allow one symbol table for now */
  850                 link_elf_error(filename,
  851                     "file must have exactly one symbol table");
  852                 error = ENOEXEC;
  853                 goto out;
  854         }
  855         if (symstrindex < 0 || symstrindex > hdr->e_shnum ||
  856             shdr[symstrindex].sh_type != SHT_STRTAB) {
  857                 link_elf_error(filename, "file has invalid symbol strings");
  858                 error = ENOEXEC;
  859                 goto out;
  860         }
  861 
  862         /* Allocate space for tracking the load chunks */
  863         if (ef->nprogtab != 0)
  864                 ef->progtab = malloc(ef->nprogtab * sizeof(*ef->progtab),
  865                     M_LINKER, M_WAITOK | M_ZERO);
  866         if (ef->nreltab != 0)
  867                 ef->reltab = malloc(ef->nreltab * sizeof(*ef->reltab),
  868                     M_LINKER, M_WAITOK | M_ZERO);
  869         if (ef->nrelatab != 0)
  870                 ef->relatab = malloc(ef->nrelatab * sizeof(*ef->relatab),
  871                     M_LINKER, M_WAITOK | M_ZERO);
  872 
  873         if (symtabindex == -1) {
  874                 link_elf_error(filename, "lost symbol table index");
  875                 error = ENOEXEC;
  876                 goto out;
  877         }
  878         /* Allocate space for and load the symbol table */
  879         ef->ddbsymcnt = shdr[symtabindex].sh_size / sizeof(Elf_Sym);
  880         ef->ddbsymtab = malloc(shdr[symtabindex].sh_size, M_LINKER, M_WAITOK);
  881         error = vn_rdwr(UIO_READ, nd->ni_vp, (void *)ef->ddbsymtab,
  882             shdr[symtabindex].sh_size, shdr[symtabindex].sh_offset,
  883             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
  884             &resid, td);
  885         if (error)
  886                 goto out;
  887         if (resid != 0){
  888                 error = EINVAL;
  889                 goto out;
  890         }
  891 
  892         /* Allocate space for and load the symbol strings */
  893         ef->ddbstrcnt = shdr[symstrindex].sh_size;
  894         ef->ddbstrtab = malloc(shdr[symstrindex].sh_size, M_LINKER, M_WAITOK);
  895         error = vn_rdwr(UIO_READ, nd->ni_vp, ef->ddbstrtab,
  896             shdr[symstrindex].sh_size, shdr[symstrindex].sh_offset,
  897             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
  898             &resid, td);
  899         if (error)
  900                 goto out;
  901         if (resid != 0){
  902                 error = EINVAL;
  903                 goto out;
  904         }
  905 
  906         /* Do we have a string table for the section names?  */
  907         shstrindex = -1;
  908         if (hdr->e_shstrndx != 0 &&
  909             shdr[hdr->e_shstrndx].sh_type == SHT_STRTAB) {
  910                 shstrindex = hdr->e_shstrndx;
  911                 ef->shstrcnt = shdr[shstrindex].sh_size;
  912                 ef->shstrtab = malloc(shdr[shstrindex].sh_size, M_LINKER,
  913                     M_WAITOK);
  914                 error = vn_rdwr(UIO_READ, nd->ni_vp, ef->shstrtab,
  915                     shdr[shstrindex].sh_size, shdr[shstrindex].sh_offset,
  916                     UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
  917                     &resid, td);
  918                 if (error)
  919                         goto out;
  920                 if (resid != 0){
  921                         error = EINVAL;
  922                         goto out;
  923                 }
  924         }
  925 
  926         /* Size up code/data(progbits) and bss(nobits). */
  927         alignmask = 0;
  928         for (i = 0; i < hdr->e_shnum; i++) {
  929                 if (shdr[i].sh_size == 0)
  930                         continue;
  931                 switch (shdr[i].sh_type) {
  932                 case SHT_PROGBITS:
  933                 case SHT_NOBITS:
  934 #ifdef __amd64__
  935                 case SHT_X86_64_UNWIND:
  936 #endif
  937                 case SHT_INIT_ARRAY:
  938                 case SHT_FINI_ARRAY:
  939                         if ((shdr[i].sh_flags & SHF_ALLOC) == 0)
  940                                 break;
  941                         alignmask = shdr[i].sh_addralign - 1;
  942                         mapsize += alignmask;
  943                         mapsize &= ~alignmask;
  944                         mapsize += shdr[i].sh_size;
  945                         break;
  946                 }
  947         }
  948 
  949         /*
  950          * We know how much space we need for the text/data/bss/etc.
  951          * This stuff needs to be in a single chunk so that profiling etc
  952          * can get the bounds and gdb can associate offsets with modules
  953          */
  954         ef->object = vm_pager_allocate(OBJT_PHYS, NULL, round_page(mapsize),
  955             VM_PROT_ALL, 0, thread0.td_ucred);
  956         if (ef->object == NULL) {
  957                 error = ENOMEM;
  958                 goto out;
  959         }
  960 #if VM_NRESERVLEVEL > 0
  961         vm_object_color(ef->object, 0);
  962 #endif
  963 
  964         /*
  965          * In order to satisfy amd64's architectural requirements on the
  966          * location of code and data in the kernel's address space, request a
  967          * mapping that is above the kernel.
  968          *
  969          * Protections will be restricted once relocations are applied.
  970          */
  971 #ifdef __amd64__
  972         mapbase = KERNBASE;
  973 #else
  974         mapbase = VM_MIN_KERNEL_ADDRESS;
  975 #endif
  976         error = vm_map_find(kernel_map, ef->object, 0, &mapbase,
  977             round_page(mapsize), 0, VMFS_OPTIMAL_SPACE, VM_PROT_ALL,
  978             VM_PROT_ALL, 0);
  979         if (error != KERN_SUCCESS) {
  980                 vm_object_deallocate(ef->object);
  981                 ef->object = NULL;
  982                 error = ENOMEM;
  983                 goto out;
  984         }
  985 
  986         /* Wire the pages */
  987         error = vm_map_wire(kernel_map, mapbase,
  988             mapbase + round_page(mapsize),
  989             VM_MAP_WIRE_SYSTEM|VM_MAP_WIRE_NOHOLES);
  990         if (error != KERN_SUCCESS) {
  991                 error = ENOMEM;
  992                 goto out;
  993         }
  994 
  995         /* Inform the kld system about the situation */
  996         lf->address = ef->address = (caddr_t)mapbase;
  997         lf->size = mapsize;
  998 
  999         /*
 1000          * Now load code/data(progbits), zero bss(nobits), allocate space for
 1001          * and load relocs
 1002          */
 1003         pb = 0;
 1004         rl = 0;
 1005         ra = 0;
 1006         alignmask = 0;
 1007         for (i = 0; i < hdr->e_shnum; i++) {
 1008                 if (shdr[i].sh_size == 0)
 1009                         continue;
 1010                 switch (shdr[i].sh_type) {
 1011                 case SHT_PROGBITS:
 1012                 case SHT_NOBITS:
 1013 #ifdef __amd64__
 1014                 case SHT_X86_64_UNWIND:
 1015 #endif
 1016                 case SHT_INIT_ARRAY:
 1017                 case SHT_FINI_ARRAY:
 1018                         if ((shdr[i].sh_flags & SHF_ALLOC) == 0)
 1019                                 break;
 1020                         alignmask = shdr[i].sh_addralign - 1;
 1021                         mapbase += alignmask;
 1022                         mapbase &= ~alignmask;
 1023                         if (ef->shstrtab != NULL && shdr[i].sh_name != 0) {
 1024                                 ef->progtab[pb].name =
 1025                                     ef->shstrtab + shdr[i].sh_name;
 1026                                 if (!strcmp(ef->progtab[pb].name, ".ctors") ||
 1027                                     shdr[i].sh_type == SHT_INIT_ARRAY) {
 1028                                         if (lf->ctors_addr != 0) {
 1029                                                 printf(
 1030                                     "%s: multiple ctor sections in %s\n",
 1031                                                     __func__, filename);
 1032                                         } else {
 1033                                                 lf->ctors_addr =
 1034                                                     (caddr_t)mapbase;
 1035                                                 lf->ctors_size =
 1036                                                     shdr[i].sh_size;
 1037                                         }
 1038                                 } else if (!strcmp(ef->progtab[pb].name,
 1039                                     ".dtors") ||
 1040                                     shdr[i].sh_type == SHT_FINI_ARRAY) {
 1041                                         if (lf->dtors_addr != 0) {
 1042                                                 printf(
 1043                                     "%s: multiple dtor sections in %s\n",
 1044                                                     __func__, filename);
 1045                                         } else {
 1046                                                 lf->dtors_addr =
 1047                                                     (caddr_t)mapbase;
 1048                                                 lf->dtors_size =
 1049                                                     shdr[i].sh_size;
 1050                                         }
 1051                                 }
 1052                         } else if (shdr[i].sh_type == SHT_PROGBITS)
 1053                                 ef->progtab[pb].name = "<<PROGBITS>>";
 1054 #ifdef __amd64__
 1055                         else if (shdr[i].sh_type == SHT_X86_64_UNWIND)
 1056                                 ef->progtab[pb].name = "<<UNWIND>>";
 1057 #endif
 1058                         else
 1059                                 ef->progtab[pb].name = "<<NOBITS>>";
 1060                         if (ef->progtab[pb].name != NULL && 
 1061                             !strcmp(ef->progtab[pb].name, DPCPU_SETNAME)) {
 1062                                 ef->progtab[pb].addr =
 1063                                     dpcpu_alloc(shdr[i].sh_size);
 1064                                 if (ef->progtab[pb].addr == NULL) {
 1065                                         printf("%s: pcpu module space is out "
 1066                                             "of space; cannot allocate %#jx "
 1067                                             "for %s\n", __func__,
 1068                                             (uintmax_t)shdr[i].sh_size,
 1069                                             filename);
 1070                                 }
 1071                         }
 1072 #ifdef VIMAGE
 1073                         else if (ef->progtab[pb].name != NULL &&
 1074                             !strcmp(ef->progtab[pb].name, VNET_SETNAME)) {
 1075                                 ef->progtab[pb].addr =
 1076                                     vnet_data_alloc(shdr[i].sh_size);
 1077                                 if (ef->progtab[pb].addr == NULL) {
 1078                                         printf("%s: vnet module space is out "
 1079                                             "of space; cannot allocate %#jx "
 1080                                             "for %s\n", __func__,
 1081                                             (uintmax_t)shdr[i].sh_size,
 1082                                             filename);
 1083                                 }
 1084                         }
 1085 #endif
 1086                         else
 1087                                 ef->progtab[pb].addr =
 1088                                     (void *)(uintptr_t)mapbase;
 1089                         if (ef->progtab[pb].addr == NULL) {
 1090                                 error = ENOSPC;
 1091                                 goto out;
 1092                         }
 1093                         ef->progtab[pb].size = shdr[i].sh_size;
 1094                         ef->progtab[pb].flags = shdr[i].sh_flags;
 1095                         ef->progtab[pb].sec = i;
 1096                         if (shdr[i].sh_type == SHT_PROGBITS
 1097 #ifdef __amd64__
 1098                             || shdr[i].sh_type == SHT_X86_64_UNWIND
 1099 #endif
 1100                             ) {
 1101                                 error = vn_rdwr(UIO_READ, nd->ni_vp,
 1102                                     ef->progtab[pb].addr,
 1103                                     shdr[i].sh_size, shdr[i].sh_offset,
 1104                                     UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred,
 1105                                     NOCRED, &resid, td);
 1106                                 if (error)
 1107                                         goto out;
 1108                                 if (resid != 0){
 1109                                         error = EINVAL;
 1110                                         goto out;
 1111                                 }
 1112                                 /* Initialize the per-cpu or vnet area. */
 1113                                 if (ef->progtab[pb].addr != (void *)mapbase &&
 1114                                     !strcmp(ef->progtab[pb].name, DPCPU_SETNAME))
 1115                                         dpcpu_copy(ef->progtab[pb].addr,
 1116                                             shdr[i].sh_size);
 1117 #ifdef VIMAGE
 1118                                 else if (ef->progtab[pb].addr !=
 1119                                     (void *)mapbase &&
 1120                                     !strcmp(ef->progtab[pb].name, VNET_SETNAME))
 1121                                         vnet_data_copy(ef->progtab[pb].addr,
 1122                                             shdr[i].sh_size);
 1123 #endif
 1124                         } else
 1125                                 bzero(ef->progtab[pb].addr, shdr[i].sh_size);
 1126 
 1127                         /* Update all symbol values with the offset. */
 1128                         for (j = 0; j < ef->ddbsymcnt; j++) {
 1129                                 es = &ef->ddbsymtab[j];
 1130                                 if (es->st_shndx != i)
 1131                                         continue;
 1132                                 es->st_value += (Elf_Addr)ef->progtab[pb].addr;
 1133                         }
 1134                         mapbase += shdr[i].sh_size;
 1135                         pb++;
 1136                         break;
 1137                 case SHT_REL:
 1138                         if ((shdr[shdr[i].sh_info].sh_flags & SHF_ALLOC) == 0)
 1139                                 break;
 1140                         ef->reltab[rl].rel = malloc(shdr[i].sh_size, M_LINKER,
 1141                             M_WAITOK);
 1142                         ef->reltab[rl].nrel = shdr[i].sh_size / sizeof(Elf_Rel);
 1143                         ef->reltab[rl].sec = shdr[i].sh_info;
 1144                         error = vn_rdwr(UIO_READ, nd->ni_vp,
 1145                             (void *)ef->reltab[rl].rel,
 1146                             shdr[i].sh_size, shdr[i].sh_offset,
 1147                             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
 1148                             &resid, td);
 1149                         if (error)
 1150                                 goto out;
 1151                         if (resid != 0){
 1152                                 error = EINVAL;
 1153                                 goto out;
 1154                         }
 1155                         rl++;
 1156                         break;
 1157                 case SHT_RELA:
 1158                         if ((shdr[shdr[i].sh_info].sh_flags & SHF_ALLOC) == 0)
 1159                                 break;
 1160                         ef->relatab[ra].rela = malloc(shdr[i].sh_size, M_LINKER,
 1161                             M_WAITOK);
 1162                         ef->relatab[ra].nrela =
 1163                             shdr[i].sh_size / sizeof(Elf_Rela);
 1164                         ef->relatab[ra].sec = shdr[i].sh_info;
 1165                         error = vn_rdwr(UIO_READ, nd->ni_vp,
 1166                             (void *)ef->relatab[ra].rela,
 1167                             shdr[i].sh_size, shdr[i].sh_offset,
 1168                             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
 1169                             &resid, td);
 1170                         if (error)
 1171                                 goto out;
 1172                         if (resid != 0){
 1173                                 error = EINVAL;
 1174                                 goto out;
 1175                         }
 1176                         ra++;
 1177                         break;
 1178                 }
 1179         }
 1180         if (pb != ef->nprogtab) {
 1181                 link_elf_error(filename, "lost progbits");
 1182                 error = ENOEXEC;
 1183                 goto out;
 1184         }
 1185         if (rl != ef->nreltab) {
 1186                 link_elf_error(filename, "lost reltab");
 1187                 error = ENOEXEC;
 1188                 goto out;
 1189         }
 1190         if (ra != ef->nrelatab) {
 1191                 link_elf_error(filename, "lost relatab");
 1192                 error = ENOEXEC;
 1193                 goto out;
 1194         }
 1195         if (mapbase != (vm_offset_t)ef->address + mapsize) {
 1196                 printf(
 1197                     "%s: mapbase 0x%lx != address %p + mapsize 0x%lx (0x%lx)\n",
 1198                     filename != NULL ? filename : "<none>",
 1199                     (u_long)mapbase, ef->address, (u_long)mapsize,
 1200                     (u_long)(vm_offset_t)ef->address + mapsize);
 1201                 error = ENOMEM;
 1202                 goto out;
 1203         }
 1204 
 1205         /* Local intra-module relocations */
 1206         error = link_elf_reloc_local(lf, false);
 1207         if (error != 0)
 1208                 goto out;
 1209 
 1210         /* Pull in dependencies */
 1211         VOP_UNLOCK(nd->ni_vp);
 1212         error = linker_load_dependencies(lf);
 1213         vn_lock(nd->ni_vp, LK_EXCLUSIVE | LK_RETRY);
 1214         if (error)
 1215                 goto out;
 1216 
 1217         /* External relocations */
 1218         error = relocate_file(ef);
 1219         if (error)
 1220                 goto out;
 1221 
 1222         /* Notify MD code that a module is being loaded. */
 1223         error = elf_cpu_load_file(lf);
 1224         if (error)
 1225                 goto out;
 1226 
 1227 #if defined(__i386__) || defined(__amd64__)
 1228         /* Now ifuncs. */
 1229         error = link_elf_reloc_local(lf, true);
 1230         if (error != 0)
 1231                 goto out;
 1232 #endif
 1233 
 1234         link_elf_protect(ef);
 1235         link_elf_invoke_cbs(lf->ctors_addr, lf->ctors_size);
 1236         *result = lf;
 1237 
 1238 out:
 1239         VOP_UNLOCK(nd->ni_vp);
 1240         vn_close(nd->ni_vp, FREAD, td->td_ucred, td);
 1241         free(nd, M_TEMP);
 1242         if (error && lf)
 1243                 linker_file_unload(lf, LINKER_UNLOAD_FORCE);
 1244         free(hdr, M_LINKER);
 1245 
 1246         return error;
 1247 }
 1248 
 1249 static void
 1250 link_elf_unload_file(linker_file_t file)
 1251 {
 1252         elf_file_t ef = (elf_file_t) file;
 1253         u_int i;
 1254 
 1255         link_elf_invoke_cbs(file->dtors_addr, file->dtors_size);
 1256 
 1257         /* Notify MD code that a module is being unloaded. */
 1258         elf_cpu_unload_file(file);
 1259 
 1260         if (ef->progtab) {
 1261                 for (i = 0; i < ef->nprogtab; i++) {
 1262                         if (ef->progtab[i].size == 0)
 1263                                 continue;
 1264                         if (ef->progtab[i].name == NULL)
 1265                                 continue;
 1266                         if (!strcmp(ef->progtab[i].name, DPCPU_SETNAME))
 1267                                 dpcpu_free(ef->progtab[i].addr,
 1268                                     ef->progtab[i].size);
 1269 #ifdef VIMAGE
 1270                         else if (!strcmp(ef->progtab[i].name, VNET_SETNAME))
 1271                                 vnet_data_free(ef->progtab[i].addr,
 1272                                     ef->progtab[i].size);
 1273 #endif
 1274                 }
 1275         }
 1276         if (ef->preloaded) {
 1277                 free(ef->reltab, M_LINKER);
 1278                 free(ef->relatab, M_LINKER);
 1279                 free(ef->progtab, M_LINKER);
 1280                 free(ef->ctftab, M_LINKER);
 1281                 free(ef->ctfoff, M_LINKER);
 1282                 free(ef->typoff, M_LINKER);
 1283                 if (file->pathname != NULL)
 1284                         preload_delete_name(file->pathname);
 1285                 return;
 1286         }
 1287 
 1288         for (i = 0; i < ef->nreltab; i++)
 1289                 free(ef->reltab[i].rel, M_LINKER);
 1290         for (i = 0; i < ef->nrelatab; i++)
 1291                 free(ef->relatab[i].rela, M_LINKER);
 1292         free(ef->reltab, M_LINKER);
 1293         free(ef->relatab, M_LINKER);
 1294         free(ef->progtab, M_LINKER);
 1295 
 1296         if (ef->object != NULL)
 1297                 vm_map_remove(kernel_map, (vm_offset_t)ef->address,
 1298                     (vm_offset_t)ef->address + ptoa(ef->object->size));
 1299         free(ef->e_shdr, M_LINKER);
 1300         free(ef->ddbsymtab, M_LINKER);
 1301         free(ef->ddbstrtab, M_LINKER);
 1302         free(ef->shstrtab, M_LINKER);
 1303         free(ef->ctftab, M_LINKER);
 1304         free(ef->ctfoff, M_LINKER);
 1305         free(ef->typoff, M_LINKER);
 1306 }
 1307 
 1308 static const char *
 1309 symbol_name(elf_file_t ef, Elf_Size r_info)
 1310 {
 1311         const Elf_Sym *ref;
 1312 
 1313         if (ELF_R_SYM(r_info)) {
 1314                 ref = ef->ddbsymtab + ELF_R_SYM(r_info);
 1315                 return ef->ddbstrtab + ref->st_name;
 1316         } else
 1317                 return NULL;
 1318 }
 1319 
 1320 static Elf_Addr
 1321 findbase(elf_file_t ef, int sec)
 1322 {
 1323         int i;
 1324         Elf_Addr base = 0;
 1325 
 1326         for (i = 0; i < ef->nprogtab; i++) {
 1327                 if (sec == ef->progtab[i].sec) {
 1328                         base = (Elf_Addr)ef->progtab[i].addr;
 1329                         break;
 1330                 }
 1331         }
 1332         return base;
 1333 }
 1334 
 1335 static int
 1336 relocate_file1(elf_file_t ef, bool ifuncs)
 1337 {
 1338         const Elf_Rel *rellim;
 1339         const Elf_Rel *rel;
 1340         const Elf_Rela *relalim;
 1341         const Elf_Rela *rela;
 1342         const char *symname;
 1343         const Elf_Sym *sym;
 1344         int i;
 1345         Elf_Size symidx;
 1346         Elf_Addr base;
 1347 
 1348         /* Perform relocations without addend if there are any: */
 1349         for (i = 0; i < ef->nreltab; i++) {
 1350                 rel = ef->reltab[i].rel;
 1351                 if (rel == NULL) {
 1352                         link_elf_error(ef->lf.filename, "lost a reltab!");
 1353                         return (ENOEXEC);
 1354                 }
 1355                 rellim = rel + ef->reltab[i].nrel;
 1356                 base = findbase(ef, ef->reltab[i].sec);
 1357                 if (base == 0) {
 1358                         link_elf_error(ef->lf.filename, "lost base for reltab");
 1359                         return (ENOEXEC);
 1360                 }
 1361                 for ( ; rel < rellim; rel++) {
 1362                         symidx = ELF_R_SYM(rel->r_info);
 1363                         if (symidx >= ef->ddbsymcnt)
 1364                                 continue;
 1365                         sym = ef->ddbsymtab + symidx;
 1366                         /* Local relocs are already done */
 1367                         if (ELF_ST_BIND(sym->st_info) == STB_LOCAL)
 1368                                 continue;
 1369                         if ((ELF_ST_TYPE(sym->st_info) == STT_GNU_IFUNC ||
 1370                             elf_is_ifunc_reloc(rel->r_info)) != ifuncs)
 1371                                 continue;
 1372                         if (elf_reloc(&ef->lf, base, rel, ELF_RELOC_REL,
 1373                             elf_obj_lookup)) {
 1374                                 symname = symbol_name(ef, rel->r_info);
 1375                                 printf("link_elf_obj: symbol %s undefined\n",
 1376                                     symname);
 1377                                 return (ENOENT);
 1378                         }
 1379                 }
 1380         }
 1381 
 1382         /* Perform relocations with addend if there are any: */
 1383         for (i = 0; i < ef->nrelatab; i++) {
 1384                 rela = ef->relatab[i].rela;
 1385                 if (rela == NULL) {
 1386                         link_elf_error(ef->lf.filename, "lost a relatab!");
 1387                         return (ENOEXEC);
 1388                 }
 1389                 relalim = rela + ef->relatab[i].nrela;
 1390                 base = findbase(ef, ef->relatab[i].sec);
 1391                 if (base == 0) {
 1392                         link_elf_error(ef->lf.filename,
 1393                             "lost base for relatab");
 1394                         return (ENOEXEC);
 1395                 }
 1396                 for ( ; rela < relalim; rela++) {
 1397                         symidx = ELF_R_SYM(rela->r_info);
 1398                         if (symidx >= ef->ddbsymcnt)
 1399                                 continue;
 1400                         sym = ef->ddbsymtab + symidx;
 1401                         /* Local relocs are already done */
 1402                         if (ELF_ST_BIND(sym->st_info) == STB_LOCAL)
 1403                                 continue;
 1404                         if ((ELF_ST_TYPE(sym->st_info) == STT_GNU_IFUNC ||
 1405                             elf_is_ifunc_reloc(rela->r_info)) != ifuncs)
 1406                                 continue;
 1407                         if (elf_reloc(&ef->lf, base, rela, ELF_RELOC_RELA,
 1408                             elf_obj_lookup)) {
 1409                                 symname = symbol_name(ef, rela->r_info);
 1410                                 printf("link_elf_obj: symbol %s undefined\n",
 1411                                     symname);
 1412                                 return (ENOENT);
 1413                         }
 1414                 }
 1415         }
 1416 
 1417         /*
 1418          * Only clean SHN_FBSD_CACHED for successful return.  If we
 1419          * modified symbol table for the object but found an
 1420          * unresolved symbol, there is no reason to roll back.
 1421          */
 1422         elf_obj_cleanup_globals_cache(ef);
 1423 
 1424         return (0);
 1425 }
 1426 
 1427 static int
 1428 relocate_file(elf_file_t ef)
 1429 {
 1430         int error;
 1431 
 1432         error = relocate_file1(ef, false);
 1433         if (error == 0)
 1434                 error = relocate_file1(ef, true);
 1435         return (error);
 1436 }
 1437 
 1438 static int
 1439 link_elf_lookup_symbol1(linker_file_t lf, const char *name, c_linker_sym_t *sym,
 1440     bool see_local)
 1441 {
 1442         elf_file_t ef = (elf_file_t)lf;
 1443         const Elf_Sym *symp;
 1444         const char *strp;
 1445         int i;
 1446 
 1447         for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
 1448                 strp = ef->ddbstrtab + symp->st_name;
 1449                 if (symp->st_shndx != SHN_UNDEF && strcmp(name, strp) == 0) {
 1450                         if (see_local ||
 1451                             ELF_ST_BIND(symp->st_info) == STB_GLOBAL) {
 1452                                 *sym = (c_linker_sym_t) symp;
 1453                                 return (0);
 1454                         }
 1455                         return (ENOENT);
 1456                 }
 1457         }
 1458         return (ENOENT);
 1459 }
 1460 
 1461 static int
 1462 link_elf_lookup_symbol(linker_file_t lf, const char *name, c_linker_sym_t *sym)
 1463 {
 1464         return (link_elf_lookup_symbol1(lf, name, sym,
 1465             link_elf_obj_leak_locals));
 1466 }
 1467 
 1468 static int
 1469 link_elf_lookup_debug_symbol(linker_file_t lf, const char *name,
 1470     c_linker_sym_t *sym)
 1471 {
 1472         return (link_elf_lookup_symbol1(lf, name, sym, true));
 1473 }
 1474 
 1475 static int
 1476 link_elf_symbol_values1(linker_file_t lf, c_linker_sym_t sym,
 1477     linker_symval_t *symval, bool see_local)
 1478 {
 1479         elf_file_t ef;
 1480         const Elf_Sym *es;
 1481         caddr_t val;
 1482 
 1483         ef = (elf_file_t) lf;
 1484         es = (const Elf_Sym*) sym;
 1485         val = (caddr_t)es->st_value;
 1486         if (es >= ef->ddbsymtab && es < (ef->ddbsymtab + ef->ddbsymcnt)) {
 1487                 if (!see_local && ELF_ST_BIND(es->st_info) == STB_LOCAL)
 1488                         return (ENOENT);
 1489                 symval->name = ef->ddbstrtab + es->st_name;
 1490                 val = (caddr_t)es->st_value;
 1491                 if (ELF_ST_TYPE(es->st_info) == STT_GNU_IFUNC)
 1492                         val = ((caddr_t (*)(void))val)();
 1493                 symval->value = val;
 1494                 symval->size = es->st_size;
 1495                 return (0);
 1496         }
 1497         return (ENOENT);
 1498 }
 1499 
 1500 static int
 1501 link_elf_symbol_values(linker_file_t lf, c_linker_sym_t sym,
 1502     linker_symval_t *symval)
 1503 {
 1504         return (link_elf_symbol_values1(lf, sym, symval,
 1505             link_elf_obj_leak_locals));
 1506 }
 1507 
 1508 static int
 1509 link_elf_debug_symbol_values(linker_file_t lf, c_linker_sym_t sym,
 1510     linker_symval_t *symval)
 1511 {
 1512         return (link_elf_symbol_values1(lf, sym, symval, true));
 1513 }
 1514 
 1515 static int
 1516 link_elf_search_symbol(linker_file_t lf, caddr_t value,
 1517     c_linker_sym_t *sym, long *diffp)
 1518 {
 1519         elf_file_t ef = (elf_file_t)lf;
 1520         u_long off = (uintptr_t)(void *)value;
 1521         u_long diff = off;
 1522         u_long st_value;
 1523         const Elf_Sym *es;
 1524         const Elf_Sym *best = NULL;
 1525         int i;
 1526 
 1527         for (i = 0, es = ef->ddbsymtab; i < ef->ddbsymcnt; i++, es++) {
 1528                 if (es->st_name == 0)
 1529                         continue;
 1530                 st_value = es->st_value;
 1531                 if (off >= st_value) {
 1532                         if (off - st_value < diff) {
 1533                                 diff = off - st_value;
 1534                                 best = es;
 1535                                 if (diff == 0)
 1536                                         break;
 1537                         } else if (off - st_value == diff) {
 1538                                 best = es;
 1539                         }
 1540                 }
 1541         }
 1542         if (best == NULL)
 1543                 *diffp = off;
 1544         else
 1545                 *diffp = diff;
 1546         *sym = (c_linker_sym_t) best;
 1547 
 1548         return (0);
 1549 }
 1550 
 1551 /*
 1552  * Look up a linker set on an ELF system.
 1553  */
 1554 static int
 1555 link_elf_lookup_set(linker_file_t lf, const char *name,
 1556     void ***startp, void ***stopp, int *countp)
 1557 {
 1558         elf_file_t ef = (elf_file_t)lf;
 1559         void **start, **stop;
 1560         int i, count;
 1561 
 1562         /* Relative to section number */
 1563         for (i = 0; i < ef->nprogtab; i++) {
 1564                 if ((strncmp(ef->progtab[i].name, "set_", 4) == 0) &&
 1565                     strcmp(ef->progtab[i].name + 4, name) == 0) {
 1566                         start  = (void **)ef->progtab[i].addr;
 1567                         stop = (void **)((char *)ef->progtab[i].addr +
 1568                             ef->progtab[i].size);
 1569                         count = stop - start;
 1570                         if (startp)
 1571                                 *startp = start;
 1572                         if (stopp)
 1573                                 *stopp = stop;
 1574                         if (countp)
 1575                                 *countp = count;
 1576                         return (0);
 1577                 }
 1578         }
 1579         return (ESRCH);
 1580 }
 1581 
 1582 static int
 1583 link_elf_each_function_name(linker_file_t file,
 1584     int (*callback)(const char *, void *), void *opaque)
 1585 {
 1586         elf_file_t ef = (elf_file_t)file;
 1587         const Elf_Sym *symp;
 1588         int i, error;
 1589 
 1590         /* Exhaustive search */
 1591         for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
 1592                 if (symp->st_value != 0 &&
 1593                     (ELF_ST_TYPE(symp->st_info) == STT_FUNC ||
 1594                     ELF_ST_TYPE(symp->st_info) == STT_GNU_IFUNC)) {
 1595                         error = callback(ef->ddbstrtab + symp->st_name, opaque);
 1596                         if (error)
 1597                                 return (error);
 1598                 }
 1599         }
 1600         return (0);
 1601 }
 1602 
 1603 static int
 1604 link_elf_each_function_nameval(linker_file_t file,
 1605     linker_function_nameval_callback_t callback, void *opaque)
 1606 {
 1607         linker_symval_t symval;
 1608         elf_file_t ef = (elf_file_t)file;
 1609         const Elf_Sym *symp;
 1610         int i, error;
 1611 
 1612         /* Exhaustive search */
 1613         for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
 1614                 if (symp->st_value != 0 &&
 1615                     (ELF_ST_TYPE(symp->st_info) == STT_FUNC ||
 1616                     ELF_ST_TYPE(symp->st_info) == STT_GNU_IFUNC)) {
 1617                         error = link_elf_debug_symbol_values(file,
 1618                             (c_linker_sym_t)symp, &symval);
 1619                         if (error == 0)
 1620                                 error = callback(file, i, &symval, opaque);
 1621                         if (error != 0)
 1622                                 return (error);
 1623                 }
 1624         }
 1625         return (0);
 1626 }
 1627 
 1628 static void
 1629 elf_obj_cleanup_globals_cache(elf_file_t ef)
 1630 {
 1631         Elf_Sym *sym;
 1632         Elf_Size i;
 1633 
 1634         for (i = 0; i < ef->ddbsymcnt; i++) {
 1635                 sym = ef->ddbsymtab + i;
 1636                 if (sym->st_shndx == SHN_FBSD_CACHED) {
 1637                         sym->st_shndx = SHN_UNDEF;
 1638                         sym->st_value = 0;
 1639                 }
 1640         }
 1641 }
 1642 
 1643 /*
 1644  * Symbol lookup function that can be used when the symbol index is known (ie
 1645  * in relocations). It uses the symbol index instead of doing a fully fledged
 1646  * hash table based lookup when such is valid. For example for local symbols.
 1647  * This is not only more efficient, it's also more correct. It's not always
 1648  * the case that the symbol can be found through the hash table.
 1649  */
 1650 static int
 1651 elf_obj_lookup(linker_file_t lf, Elf_Size symidx, int deps, Elf_Addr *res)
 1652 {
 1653         elf_file_t ef = (elf_file_t)lf;
 1654         Elf_Sym *sym;
 1655         const char *symbol;
 1656         Elf_Addr res1;
 1657 
 1658         /* Don't even try to lookup the symbol if the index is bogus. */
 1659         if (symidx >= ef->ddbsymcnt) {
 1660                 *res = 0;
 1661                 return (EINVAL);
 1662         }
 1663 
 1664         sym = ef->ddbsymtab + symidx;
 1665 
 1666         /* Quick answer if there is a definition included. */
 1667         if (sym->st_shndx != SHN_UNDEF) {
 1668                 res1 = (Elf_Addr)sym->st_value;
 1669                 if (ELF_ST_TYPE(sym->st_info) == STT_GNU_IFUNC)
 1670                         res1 = ((Elf_Addr (*)(void))res1)();
 1671                 *res = res1;
 1672                 return (0);
 1673         }
 1674 
 1675         /* If we get here, then it is undefined and needs a lookup. */
 1676         switch (ELF_ST_BIND(sym->st_info)) {
 1677         case STB_LOCAL:
 1678                 /* Local, but undefined? huh? */
 1679                 *res = 0;
 1680                 return (EINVAL);
 1681 
 1682         case STB_GLOBAL:
 1683         case STB_WEAK:
 1684                 /* Relative to Data or Function name */
 1685                 symbol = ef->ddbstrtab + sym->st_name;
 1686 
 1687                 /* Force a lookup failure if the symbol name is bogus. */
 1688                 if (*symbol == 0) {
 1689                         *res = 0;
 1690                         return (EINVAL);
 1691                 }
 1692                 res1 = (Elf_Addr)linker_file_lookup_symbol(lf, symbol, deps);
 1693 
 1694                 /*
 1695                  * Cache global lookups during module relocation. The failure
 1696                  * case is particularly expensive for callers, who must scan
 1697                  * through the entire globals table doing strcmp(). Cache to
 1698                  * avoid doing such work repeatedly.
 1699                  *
 1700                  * After relocation is complete, undefined globals will be
 1701                  * restored to SHN_UNDEF in elf_obj_cleanup_globals_cache(),
 1702                  * above.
 1703                  */
 1704                 if (res1 != 0) {
 1705                         sym->st_shndx = SHN_FBSD_CACHED;
 1706                         sym->st_value = res1;
 1707                         *res = res1;
 1708                         return (0);
 1709                 } else if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
 1710                         sym->st_value = 0;
 1711                         *res = 0;
 1712                         return (0);
 1713                 }
 1714                 return (EINVAL);
 1715 
 1716         default:
 1717                 return (EINVAL);
 1718         }
 1719 }
 1720 
 1721 static void
 1722 link_elf_fix_link_set(elf_file_t ef)
 1723 {
 1724         static const char startn[] = "__start_";
 1725         static const char stopn[] = "__stop_";
 1726         Elf_Sym *sym;
 1727         const char *sym_name, *linkset_name;
 1728         Elf_Addr startp, stopp;
 1729         Elf_Size symidx;
 1730         int start, i;
 1731 
 1732         startp = stopp = 0;
 1733         for (symidx = 1 /* zero entry is special */;
 1734                 symidx < ef->ddbsymcnt; symidx++) {
 1735                 sym = ef->ddbsymtab + symidx;
 1736                 if (sym->st_shndx != SHN_UNDEF)
 1737                         continue;
 1738 
 1739                 sym_name = ef->ddbstrtab + sym->st_name;
 1740                 if (strncmp(sym_name, startn, sizeof(startn) - 1) == 0) {
 1741                         start = 1;
 1742                         linkset_name = sym_name + sizeof(startn) - 1;
 1743                 }
 1744                 else if (strncmp(sym_name, stopn, sizeof(stopn) - 1) == 0) {
 1745                         start = 0;
 1746                         linkset_name = sym_name + sizeof(stopn) - 1;
 1747                 }
 1748                 else
 1749                         continue;
 1750 
 1751                 for (i = 0; i < ef->nprogtab; i++) {
 1752                         if (strcmp(ef->progtab[i].name, linkset_name) == 0) {
 1753                                 startp = (Elf_Addr)ef->progtab[i].addr;
 1754                                 stopp = (Elf_Addr)(startp + ef->progtab[i].size);
 1755                                 break;
 1756                         }
 1757                 }
 1758                 if (i == ef->nprogtab)
 1759                         continue;
 1760 
 1761                 sym->st_value = start ? startp : stopp;
 1762                 sym->st_shndx = i;
 1763         }
 1764 }
 1765 
 1766 static int
 1767 link_elf_reloc_local(linker_file_t lf, bool ifuncs)
 1768 {
 1769         elf_file_t ef = (elf_file_t)lf;
 1770         const Elf_Rel *rellim;
 1771         const Elf_Rel *rel;
 1772         const Elf_Rela *relalim;
 1773         const Elf_Rela *rela;
 1774         const Elf_Sym *sym;
 1775         Elf_Addr base;
 1776         int i;
 1777         Elf_Size symidx;
 1778 
 1779         link_elf_fix_link_set(ef);
 1780 
 1781         /* Perform relocations without addend if there are any: */
 1782         for (i = 0; i < ef->nreltab; i++) {
 1783                 rel = ef->reltab[i].rel;
 1784                 if (rel == NULL) {
 1785                         link_elf_error(ef->lf.filename, "lost a reltab");
 1786                         return (ENOEXEC);
 1787                 }
 1788                 rellim = rel + ef->reltab[i].nrel;
 1789                 base = findbase(ef, ef->reltab[i].sec);
 1790                 if (base == 0) {
 1791                         link_elf_error(ef->lf.filename, "lost base for reltab");
 1792                         return (ENOEXEC);
 1793                 }
 1794                 for ( ; rel < rellim; rel++) {
 1795                         symidx = ELF_R_SYM(rel->r_info);
 1796                         if (symidx >= ef->ddbsymcnt)
 1797                                 continue;
 1798                         sym = ef->ddbsymtab + symidx;
 1799                         /* Only do local relocs */
 1800                         if (ELF_ST_BIND(sym->st_info) != STB_LOCAL)
 1801                                 continue;
 1802                         if ((ELF_ST_TYPE(sym->st_info) == STT_GNU_IFUNC ||
 1803                             elf_is_ifunc_reloc(rel->r_info)) != ifuncs)
 1804                                 continue;
 1805                         if (elf_reloc_local(lf, base, rel, ELF_RELOC_REL,
 1806                             elf_obj_lookup) != 0)
 1807                                 return (ENOEXEC);
 1808                 }
 1809         }
 1810 
 1811         /* Perform relocations with addend if there are any: */
 1812         for (i = 0; i < ef->nrelatab; i++) {
 1813                 rela = ef->relatab[i].rela;
 1814                 if (rela == NULL) {
 1815                         link_elf_error(ef->lf.filename, "lost a relatab!");
 1816                         return (ENOEXEC);
 1817                 }
 1818                 relalim = rela + ef->relatab[i].nrela;
 1819                 base = findbase(ef, ef->relatab[i].sec);
 1820                 if (base == 0) {
 1821                         link_elf_error(ef->lf.filename, "lost base for reltab");
 1822                         return (ENOEXEC);
 1823                 }
 1824                 for ( ; rela < relalim; rela++) {
 1825                         symidx = ELF_R_SYM(rela->r_info);
 1826                         if (symidx >= ef->ddbsymcnt)
 1827                                 continue;
 1828                         sym = ef->ddbsymtab + symidx;
 1829                         /* Only do local relocs */
 1830                         if (ELF_ST_BIND(sym->st_info) != STB_LOCAL)
 1831                                 continue;
 1832                         if ((ELF_ST_TYPE(sym->st_info) == STT_GNU_IFUNC ||
 1833                             elf_is_ifunc_reloc(rela->r_info)) != ifuncs)
 1834                                 continue;
 1835                         if (elf_reloc_local(lf, base, rela, ELF_RELOC_RELA,
 1836                             elf_obj_lookup) != 0)
 1837                                 return (ENOEXEC);
 1838                 }
 1839         }
 1840         return (0);
 1841 }
 1842 
 1843 static long
 1844 link_elf_symtab_get(linker_file_t lf, const Elf_Sym **symtab)
 1845 {
 1846         elf_file_t ef = (elf_file_t)lf;
 1847 
 1848         *symtab = ef->ddbsymtab;
 1849         if (*symtab == NULL)
 1850                 return (0);
 1851         return (ef->ddbsymcnt);
 1852 }
 1853     
 1854 static long
 1855 link_elf_strtab_get(linker_file_t lf, caddr_t *strtab)
 1856 {
 1857         elf_file_t ef = (elf_file_t)lf;
 1858 
 1859         *strtab = ef->ddbstrtab;
 1860         if (*strtab == NULL)
 1861                 return (0);
 1862         return (ef->ddbstrcnt);
 1863 }

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