sys/kern/imgact_elf.c

   1 /*-
   2  * Copyright (c) 2000 David O'Brien
   3  * Copyright (c) 1995-1996 Søren Schmidt
   4  * Copyright (c) 1996 Peter Wemm
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer
  12  *    in this position and unchanged.
  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  * 3. The name of the author may not be used to endorse or promote products
  17  *    derived from this software without specific prior written permission
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  20  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  21  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  22  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  23  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  24  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  28  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  29  *
  30  * $FreeBSD: src/sys/kern/imgact_elf.c,v 1.73.2.13 2002/12/28 19:49:41 dillon Exp $
  31  */
  32
  33 #include <sys/param.h>
  34 #include <sys/exec.h>
  35 #include <sys/fcntl.h>
  36 #include <sys/file.h>
  37 #include <sys/imgact.h>
  38 #include <sys/imgact_elf.h>
  39 #include <sys/kernel.h>
  40 #include <sys/malloc.h>
  41 #include <sys/mman.h>
  42 #include <sys/systm.h>
  43 #include <sys/proc.h>
  44 #include <sys/nlookup.h>
  45 #include <sys/pioctl.h>
  46 #include <sys/procfs.h>
  47 #include <sys/resourcevar.h>
  48 #include <sys/signalvar.h>
  49 #include <sys/stat.h>
  50 #include <sys/syscall.h>
  51 #include <sys/sysctl.h>
  52 #include <sys/sysent.h>
  53 #include <sys/vnode.h>
  54 #include <sys/eventhandler.h>
  55
  56 #include <cpu/lwbuf.h>
  57
  58 #include <vm/vm.h>
  59 #include <vm/vm_kern.h>
  60 #include <vm/vm_param.h>
  61 #include <vm/pmap.h>
  62 #include <sys/lock.h>
  63 #include <vm/vm_map.h>
  64 #include <vm/vm_object.h>
  65 #include <vm/vm_extern.h>
  66
  67 #include <machine/elf.h>
  68 #include <machine/md_var.h>
  69 #include <sys/mount.h>
  70 #include <sys/ckpt.h>
  71
  72 #define OLD_EI_BRAND    8
  73 #define truncps(va,ps)  ((va) & ~(ps - 1))
  74 #define aligned(a,t)    (truncps((u_long)(a), sizeof(t)) == (u_long)(a))
  75
  76 static int __elfN(check_header)(const Elf_Ehdr *hdr);
  77 static Elf_Brandinfo *__elfN(get_brandinfo)(struct image_params *imgp,
  78     const char *interp, int32_t *osrel);
  79 static int __elfN(load_file)(struct proc *p, const char *file, u_long *addr,
  80     u_long *entry);
  81 static int __elfN(load_section)(struct proc *p,
  82     struct vmspace *vmspace, struct vnode *vp,
  83     vm_offset_t offset, caddr_t vmaddr, size_t memsz, size_t filsz,
  84     vm_prot_t prot);
  85 static int __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp);
  86 static boolean_t __elfN(bsd_trans_osrel)(const Elf_Note *note,
  87     int32_t *osrel);
  88 static boolean_t __elfN(check_note)(struct image_params *imgp,
  89     Elf_Brandnote *checknote, int32_t *osrel);
  90 static vm_prot_t __elfN(trans_prot)(Elf_Word);
  91 static Elf_Word __elfN(untrans_prot)(vm_prot_t);
  92 static boolean_t check_PT_NOTE(struct image_params *imgp,
  93     Elf_Brandnote *checknote, int32_t *osrel, const Elf_Phdr * pnote);
  94 static boolean_t extract_interpreter(struct image_params *imgp,
  95     const Elf_Phdr *pinterpreter, char *data);
  96
  97 static int elf_legacy_coredump = 0;
  98 static int __elfN(fallback_brand) = -1;
  99 #if defined(__x86_64__)
 100 SYSCTL_NODE(_kern, OID_AUTO, elf64, CTLFLAG_RW, 0, "");
 101 SYSCTL_INT(_debug, OID_AUTO, elf64_legacy_coredump, CTLFLAG_RW,
 102     &elf_legacy_coredump, 0, "legacy coredump mode");
 103 SYSCTL_INT(_kern_elf64, OID_AUTO, fallback_brand, CTLFLAG_RW,
 104     &elf64_fallback_brand, 0, "ELF64 brand of last resort");
 105 TUNABLE_INT("kern.elf64.fallback_brand", &elf64_fallback_brand);
 106 #else /* i386 assumed */
 107 SYSCTL_NODE(_kern, OID_AUTO, elf32, CTLFLAG_RW, 0, "");
 108 SYSCTL_INT(_debug, OID_AUTO, elf32_legacy_coredump, CTLFLAG_RW,
 109     &elf_legacy_coredump, 0, "legacy coredump mode");
 110 SYSCTL_INT(_kern_elf32, OID_AUTO, fallback_brand, CTLFLAG_RW,
 111     &elf32_fallback_brand, 0, "ELF32 brand of last resort");
 112 TUNABLE_INT("kern.elf32.fallback_brand", &elf32_fallback_brand);
 113 #endif
 114
 115 static Elf_Brandinfo *elf_brand_list[MAX_BRANDS];
 116
 117 static const char DRAGONFLY_ABI_VENDOR[] = "DragonFly";
 118 static const char FREEBSD_ABI_VENDOR[]   = "FreeBSD";
 119
 120 Elf_Brandnote __elfN(dragonfly_brandnote) = {
 121         .hdr.n_namesz   = sizeof(DRAGONFLY_ABI_VENDOR),
 122         .hdr.n_descsz   = sizeof(int32_t),
 123         .hdr.n_type     = 1,
 124         .vendor         = DRAGONFLY_ABI_VENDOR,
 125         .flags          = BN_TRANSLATE_OSREL,
 126         .trans_osrel    = __elfN(bsd_trans_osrel),
 127 };
 128
 129 Elf_Brandnote __elfN(freebsd_brandnote) = {
 130         .hdr.n_namesz   = sizeof(FREEBSD_ABI_VENDOR),
 131         .hdr.n_descsz   = sizeof(int32_t),
 132         .hdr.n_type     = 1,
 133         .vendor         = FREEBSD_ABI_VENDOR,
 134         .flags          = BN_TRANSLATE_OSREL,
 135         .trans_osrel    = __elfN(bsd_trans_osrel),
 136 };
 137
 138 int
 139 __elfN(insert_brand_entry)(Elf_Brandinfo *entry)
 140 {
 141         int i;
 142
 143         for (i = 0; i < MAX_BRANDS; i++) {
 144                 if (elf_brand_list[i] == NULL) {
 145                         elf_brand_list[i] = entry;
 146                         break;
 147                 }
 148         }
 149         if (i == MAX_BRANDS) {
 150                 uprintf("WARNING: %s: could not insert brandinfo entry: %p\n",
 151                         __func__, entry);
 152                 return (-1);
 153         }
 154         return (0);
 155 }
 156
 157 int
 158 __elfN(remove_brand_entry)(Elf_Brandinfo *entry)
 159 {
 160         int i;
 161
 162         for (i = 0; i < MAX_BRANDS; i++) {
 163                 if (elf_brand_list[i] == entry) {
 164                         elf_brand_list[i] = NULL;
 165                         break;
 166                 }
 167         }
 168         if (i == MAX_BRANDS)
 169                 return (-1);
 170         return (0);
 171 }
 172
 173 /*
 174  * Check if an elf brand is being used anywhere in the system.
 175  *
 176  * Used by the linux emulation module unloader.  This isn't safe from
 177  * races.
 178  */
 179 struct elf_brand_inuse_info {
 180         int rval;
 181         Elf_Brandinfo *entry;
 182 };
 183
 184 static int elf_brand_inuse_callback(struct proc *p, void *data);
 185
 186 int
 187 __elfN(brand_inuse)(Elf_Brandinfo *entry)
 188 {
 189         struct elf_brand_inuse_info info;
 190
 191         info.rval = FALSE;
 192         info.entry = entry;
 193         allproc_scan(elf_brand_inuse_callback, &info);
 194         return (info.rval);
 195 }
 196
 197 static
 198 int
 199 elf_brand_inuse_callback(struct proc *p, void *data)
 200 {
 201         struct elf_brand_inuse_info *info = data;
 202
 203         if (p->p_sysent == info->entry->sysvec) {
 204                 info->rval = TRUE;
 205                 return (-1);
 206         }
 207         return (0);
 208 }
 209
 210 static int
 211 __elfN(check_header)(const Elf_Ehdr *hdr)
 212 {
 213         Elf_Brandinfo *bi;
 214         int i;
 215
 216         if (!IS_ELF(*hdr) ||
 217             hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS ||
 218             hdr->e_ident[EI_DATA] != ELF_TARG_DATA ||
 219             hdr->e_ident[EI_VERSION] != EV_CURRENT ||
 220             hdr->e_phentsize != sizeof(Elf_Phdr) ||
 221             hdr->e_ehsize != sizeof(Elf_Ehdr) ||
 222             hdr->e_version != ELF_TARG_VER)
 223                 return (ENOEXEC);
 224
 225         /*
 226          * Make sure we have at least one brand for this machine.
 227          */
 228
 229         for (i = 0; i < MAX_BRANDS; i++) {
 230                 bi = elf_brand_list[i];
 231                 if (bi != NULL && bi->machine == hdr->e_machine)
 232                         break;
 233         }
 234         if (i == MAX_BRANDS)
 235                 return (ENOEXEC);
 236
 237         return (0);
 238 }
 239
 240 static int
 241 __elfN(load_section)(struct proc *p, struct vmspace *vmspace, struct vnode *vp,
 242                  vm_offset_t offset, caddr_t vmaddr, size_t memsz,
 243                  size_t filsz, vm_prot_t prot)
 244 {
 245         size_t map_len;
 246         vm_offset_t map_addr;
 247         int error, rv, cow;
 248         int count;
 249         int shared;
 250         size_t copy_len;
 251         vm_object_t object;
 252         vm_offset_t file_addr;
 253
 254         object = vp->v_object;
 255         error = 0;
 256
 257         /*
 258          * In most cases we will be able to use a shared lock on the
 259          * object we are inserting into the map.  The lock will be
 260          * upgraded in situations where new VM pages must be allocated.
 261          */
 262         vm_object_hold_shared(object);
 263         shared = 1;
 264
 265         /*
 266          * It's necessary to fail if the filsz + offset taken from the
 267          * header is greater than the actual file pager object's size.
 268          * If we were to allow this, then the vm_map_find() below would
 269          * walk right off the end of the file object and into the ether.
 270          *
 271          * While I'm here, might as well check for something else that
 272          * is invalid: filsz cannot be greater than memsz.
 273          */
 274         if ((off_t)filsz + offset > vp->v_filesize || filsz > memsz) {
 275                 uprintf("elf_load_section: truncated ELF file\n");
 276                 vm_object_drop(object);
 277                 return (ENOEXEC);
 278         }
 279
 280         map_addr = trunc_page((vm_offset_t)vmaddr);
 281         file_addr = trunc_page(offset);
 282
 283         /*
 284          * We have two choices.  We can either clear the data in the last page
 285          * of an oversized mapping, or we can start the anon mapping a page
 286          * early and copy the initialized data into that first page.  We
 287          * choose the second..
 288          */
 289         if (memsz > filsz)
 290                 map_len = trunc_page(offset+filsz) - file_addr;
 291         else
 292                 map_len = round_page(offset+filsz) - file_addr;
 293
 294         if (map_len != 0) {
 295                 vm_object_reference_locked(object);
 296
 297                 /* cow flags: don't dump readonly sections in core */
 298                 cow = MAP_COPY_ON_WRITE | MAP_PREFAULT;
 299                 if ((prot & VM_PROT_WRITE) == 0)
 300                         cow |= MAP_DISABLE_COREDUMP;
 301                 if (shared == 0)
 302                         cow |= MAP_PREFAULT_RELOCK;
 303
 304                 count = vm_map_entry_reserve(MAP_RESERVE_COUNT);
 305                 vm_map_lock(&vmspace->vm_map);
 306                 rv = vm_map_insert(&vmspace->vm_map, &count,
 307                                       object,
 308                                       file_addr,        /* file offset */
 309                                       map_addr,         /* virtual start */
 310                                       map_addr + map_len,/* virtual end */
 311                                       VM_MAPTYPE_NORMAL,
 312                                       prot, VM_PROT_ALL,
 313                                       cow);
 314                 vm_map_unlock(&vmspace->vm_map);
 315                 vm_map_entry_release(count);
 316
 317                 /*
 318                  * NOTE: Object must have a hold ref when calling
 319                  * vm_object_deallocate().
 320                  */
 321                 if (rv != KERN_SUCCESS) {
 322                         vm_object_drop(object);
 323                         vm_object_deallocate(object);
 324                         return (EINVAL);
 325                 }
 326
 327                 /* we can stop now if we've covered it all */
 328                 if (memsz == filsz) {
 329                         vm_object_drop(object);
 330                         return (0);
 331                 }
 332         }
 333
 334         /*
 335          * We have to get the remaining bit of the file into the first part
 336          * of the oversized map segment.  This is normally because the .data
 337          * segment in the file is extended to provide bss.  It's a neat idea
 338          * to try and save a page, but it's a pain in the behind to implement.
 339          */
 340         copy_len = (offset + filsz) - trunc_page(offset + filsz);
 341         map_addr = trunc_page((vm_offset_t)vmaddr + filsz);
 342         map_len = round_page((vm_offset_t)vmaddr + memsz) - map_addr;
 343
 344         /* This had damn well better be true! */
 345         if (map_len != 0) {
 346                 count = vm_map_entry_reserve(MAP_RESERVE_COUNT);
 347                 vm_map_lock(&vmspace->vm_map);
 348                 rv = vm_map_insert(&vmspace->vm_map, &count,
 349                                         NULL, 0,
 350                                         map_addr, map_addr + map_len,
 351                                         VM_MAPTYPE_NORMAL,
 352                                         VM_PROT_ALL, VM_PROT_ALL,
 353                                         0);
 354                 vm_map_unlock(&vmspace->vm_map);
 355                 vm_map_entry_release(count);
 356                 if (rv != KERN_SUCCESS) {
 357                         vm_object_drop(object);
 358                         return (EINVAL);
 359                 }
 360         }
 361
 362         if (copy_len != 0) {
 363                 struct lwbuf *lwb;
 364                 struct lwbuf lwb_cache;
 365                 vm_page_t m;
 366
 367                 m = vm_fault_object_page(object, trunc_page(offset + filsz),
 368                                          VM_PROT_READ, 0, &shared, &error);
 369                 vm_object_drop(object);
 370                 if (m) {
 371                         lwb = lwbuf_alloc(m, &lwb_cache);
 372                         error = copyout((caddr_t)lwbuf_kva(lwb),
 373                                         (caddr_t)map_addr, copy_len);
 374                         lwbuf_free(lwb);
 375                         vm_page_unhold(m);
 376                 }
 377         } else {
 378                 vm_object_drop(object);
 379         }
 380
 381         /*
 382          * set it to the specified protection
 383          */
 384         if (error == 0) {
 385                 vm_map_protect(&vmspace->vm_map,
 386                                map_addr, map_addr + map_len,
 387                                prot, FALSE);
 388         }
 389         return (error);
 390 }
 391
 392 /*
 393  * Load the file "file" into memory.  It may be either a shared object
 394  * or an executable.
 395  *
 396  * The "addr" reference parameter is in/out.  On entry, it specifies
 397  * the address where a shared object should be loaded.  If the file is
 398  * an executable, this value is ignored.  On exit, "addr" specifies
 399  * where the file was actually loaded.
 400  *
 401  * The "entry" reference parameter is out only.  On exit, it specifies
 402  * the entry point for the loaded file.
 403  */
 404 static int
 405 __elfN(load_file)(struct proc *p, const char *file, u_long *addr, u_long *entry)
 406 {
 407         struct {
 408                 struct nlookupdata nd;
 409                 struct vattr attr;
 410                 struct image_params image_params;
 411         } *tempdata;
 412         const Elf_Ehdr *hdr = NULL;
 413         const Elf_Phdr *phdr = NULL;
 414         struct nlookupdata *nd;
 415         struct vmspace *vmspace = p->p_vmspace;
 416         struct vattr *attr;
 417         struct image_params *imgp;
 418         struct mount *topmnt;
 419         vm_prot_t prot;
 420         u_long rbase;
 421         u_long base_addr = 0;
 422         int error, i, numsegs;
 423
 424         tempdata = kmalloc(sizeof(*tempdata), M_TEMP, M_WAITOK);
 425         nd = &tempdata->nd;
 426         attr = &tempdata->attr;
 427         imgp = &tempdata->image_params;
 428
 429         /*
 430          * Initialize part of the common data
 431          */
 432         imgp->proc = p;
 433         imgp->attr = attr;
 434         imgp->firstpage = NULL;
 435         imgp->image_header = NULL;
 436         imgp->vp = NULL;
 437
 438         error = nlookup_init(nd, file, UIO_SYSSPACE, NLC_FOLLOW);
 439         if (error == 0)
 440                 error = nlookup(nd);
 441         if (error == 0)
 442                 error = cache_vget(&nd->nl_nch, nd->nl_cred,
 443                                    LK_SHARED, &imgp->vp);
 444         topmnt = nd->nl_nch.mount;
 445         nlookup_done(nd);
 446         if (error)
 447                 goto fail;
 448
 449         /*
 450          * Check permissions, modes, uid, etc on the file, and "open" it.
 451          */
 452         error = exec_check_permissions(imgp, topmnt);
 453         if (error) {
 454                 vn_unlock(imgp->vp);
 455                 goto fail;
 456         }
 457
 458         error = exec_map_first_page(imgp);
 459         /*
 460          * Also make certain that the interpreter stays the same, so set
 461          * its VTEXT flag, too.
 462          */
 463         if (error == 0)
 464                 vsetflags(imgp->vp, VTEXT);
 465         vn_unlock(imgp->vp);
 466         if (error)
 467                 goto fail;
 468
 469         hdr = (const Elf_Ehdr *)imgp->image_header;
 470         if ((error = __elfN(check_header)(hdr)) != 0)
 471                 goto fail;
 472         if (hdr->e_type == ET_DYN)
 473                 rbase = *addr;
 474         else if (hdr->e_type == ET_EXEC)
 475                 rbase = 0;
 476         else {
 477                 error = ENOEXEC;
 478                 goto fail;
 479         }
 480
 481         /* Only support headers that fit within first page for now      */
 482         /*    (multiplication of two Elf_Half fields will not overflow) */
 483         if ((hdr->e_phoff > PAGE_SIZE) ||
 484             (hdr->e_phentsize * hdr->e_phnum) > PAGE_SIZE - hdr->e_phoff) {
 485                 error = ENOEXEC;
 486                 goto fail;
 487         }
 488
 489         phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff);
 490         if (!aligned(phdr, Elf_Addr)) {
 491                 error = ENOEXEC;
 492                 goto fail;
 493         }
 494
 495         for (i = 0, numsegs = 0; i < hdr->e_phnum; i++) {
 496                 if (phdr[i].p_type == PT_LOAD && phdr[i].p_memsz != 0) {
 497                         /* Loadable segment */
 498                         prot = __elfN(trans_prot)(phdr[i].p_flags);
 499                         error = __elfN(load_section)(
 500                                     p, vmspace, imgp->vp,
 501                                     phdr[i].p_offset,
 502                                     (caddr_t)phdr[i].p_vaddr +
 503                                     rbase,
 504                                     phdr[i].p_memsz,
 505                                     phdr[i].p_filesz, prot);
 506                         if (error != 0)
 507                                 goto fail;
 508                         /*
 509                          * Establish the base address if this is the
 510                          * first segment.
 511                          */
 512                         if (numsegs == 0)
 513                                 base_addr = trunc_page(phdr[i].p_vaddr + rbase);
 514                         numsegs++;
 515                 }
 516         }
 517         *addr = base_addr;
 518         *entry = (unsigned long)hdr->e_entry + rbase;
 519
 520 fail:
 521         if (imgp->firstpage)
 522                 exec_unmap_first_page(imgp);
 523         if (imgp->vp) {
 524                 vrele(imgp->vp);
 525                 imgp->vp = NULL;
 526         }
 527         kfree(tempdata, M_TEMP);
 528
 529         return (error);
 530 }
 531
 532 static Elf_Brandinfo *
 533 __elfN(get_brandinfo)(struct image_params *imgp, const char *interp,
 534     int32_t *osrel)
 535 {
 536         const Elf_Ehdr *hdr = (const Elf_Ehdr *)imgp->image_header;
 537         Elf_Brandinfo *bi;
 538         boolean_t ret;
 539         int i;
 540
 541         /* We support four types of branding -- (1) the ELF EI_OSABI field
 542          * that SCO added to the ELF spec, (2) FreeBSD 3.x's traditional string
 543          * branding within the ELF header, (3) path of the `interp_path' field,
 544          * and (4) the ".note.ABI-tag" ELF section.
 545          */
 546
 547         /* Look for an ".note.ABI-tag" ELF section */
 548         for (i = 0; i < MAX_BRANDS; i++) {
 549                 bi = elf_brand_list[i];
 550
 551                 if (bi == NULL)
 552                         continue;
 553                 if (hdr->e_machine == bi->machine && (bi->flags &
 554                     (BI_BRAND_NOTE|BI_BRAND_NOTE_MANDATORY)) != 0) {
 555                         ret = __elfN(check_note)(imgp, bi->brand_note, osrel);
 556                         if (ret)
 557                                 return (bi);
 558                 }
 559         }
 560
 561         /* If the executable has a brand, search for it in the brand list. */
 562         for (i = 0;  i < MAX_BRANDS;  i++) {
 563                 bi = elf_brand_list[i];
 564
 565                 if (bi == NULL || bi->flags & BI_BRAND_NOTE_MANDATORY)
 566                         continue;
 567                 if (hdr->e_machine == bi->machine &&
 568                     (hdr->e_ident[EI_OSABI] == bi->brand ||
 569                     strncmp((const char *)&hdr->e_ident[OLD_EI_BRAND],
 570                     bi->compat_3_brand, strlen(bi->compat_3_brand)) == 0))
 571                         return (bi);
 572         }
 573
 574         /* Lacking a known brand, search for a recognized interpreter. */
 575         if (interp != NULL) {
 576                 for (i = 0;  i < MAX_BRANDS;  i++) {
 577                         bi = elf_brand_list[i];
 578
 579                         if (bi == NULL || bi->flags & BI_BRAND_NOTE_MANDATORY)
 580                                 continue;
 581                         if (hdr->e_machine == bi->machine &&
 582                             strcmp(interp, bi->interp_path) == 0)
 583                                 return (bi);
 584                 }
 585         }
 586
 587         /* Lacking a recognized interpreter, try the default brand */
 588         for (i = 0; i < MAX_BRANDS; i++) {
 589                 bi = elf_brand_list[i];
 590
 591                 if (bi == NULL || bi->flags & BI_BRAND_NOTE_MANDATORY)
 592                         continue;
 593                 if (hdr->e_machine == bi->machine &&
 594                     __elfN(fallback_brand) == bi->brand)
 595                         return (bi);
 596         }
 597         return (NULL);
 598 }
 599
 600 static int
 601 __CONCAT(exec_,__elfN(imgact))(struct image_params *imgp)
 602 {
 603         const Elf_Ehdr *hdr = (const Elf_Ehdr *) imgp->image_header;
 604         const Elf_Phdr *phdr;
 605         Elf_Auxargs *elf_auxargs;
 606         struct vmspace *vmspace;
 607         vm_prot_t prot;
 608         u_long text_size = 0, data_size = 0, total_size = 0;
 609         u_long text_addr = 0, data_addr = 0;
 610         u_long seg_size, seg_addr;
 611         u_long addr, baddr, et_dyn_addr, entry = 0, proghdr = 0;
 612         int32_t osrel = 0;
 613         int error = 0, i, n;
 614         boolean_t failure;
 615         char *interp = NULL;
 616         const char *newinterp = NULL;
 617         Elf_Brandinfo *brand_info;
 618         char *path;
 619
 620         /*
 621          * Do we have a valid ELF header ?
 622          *
 623          * Only allow ET_EXEC & ET_DYN here, reject ET_DYN later if a particular
 624          * brand doesn't support it.  Both DragonFly platforms do by default.
 625          */
 626         if (__elfN(check_header)(hdr) != 0 ||
 627             (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN))
 628                 return (-1);
 629
 630         /*
 631          * From here on down, we return an errno, not -1, as we've
 632          * detected an ELF file.
 633          */
 634
 635         if ((hdr->e_phoff > PAGE_SIZE) ||
 636             (hdr->e_phoff + hdr->e_phentsize * hdr->e_phnum) > PAGE_SIZE) {
 637                 /* Only support headers in first page for now */
 638                 return (ENOEXEC);
 639         }
 640         phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff);
 641         if (!aligned(phdr, Elf_Addr))
 642                 return (ENOEXEC);
 643         n = 0;
 644         baddr = 0;
 645         for (i = 0; i < hdr->e_phnum; i++) {
 646                 if (phdr[i].p_type == PT_LOAD) {
 647                         if (n == 0)
 648                                 baddr = phdr[i].p_vaddr;
 649                         n++;
 650                         continue;
 651                 }
 652                 if (phdr[i].p_type == PT_INTERP) {
 653                         /*
 654                          * If interp is already defined there are more than
 655                          * one PT_INTERP program headers present.  Take only
 656                          * the first one and ignore the rest.
 657                          */
 658                         if (interp != NULL)
 659                                 continue;
 660
 661                         if (phdr[i].p_filesz == 0 ||
 662                             phdr[i].p_filesz > PAGE_SIZE ||
 663                             phdr[i].p_filesz > MAXPATHLEN)
 664                                 return (ENOEXEC);
 665
 666                         interp = kmalloc(phdr[i].p_filesz, M_TEMP, M_WAITOK);
 667                         failure = extract_interpreter(imgp, &phdr[i], interp);
 668                         if (failure) {
 669                                 kfree(interp, M_TEMP);
 670                                 return (ENOEXEC);
 671                         }
 672                         continue;
 673                 }
 674         }
 675
 676         brand_info = __elfN(get_brandinfo)(imgp, interp, &osrel);
 677         if (brand_info == NULL) {
 678                 uprintf("ELF binary type \"%u\" not known.\n",
 679                     hdr->e_ident[EI_OSABI]);
 680                 if (interp != NULL)
 681                         kfree(interp, M_TEMP);
 682                 return (ENOEXEC);
 683         }
 684         if (hdr->e_type == ET_DYN) {
 685                 if ((brand_info->flags & BI_CAN_EXEC_DYN) == 0) {
 686                         if (interp != NULL)
 687                                 kfree(interp, M_TEMP);
 688                         return (ENOEXEC);
 689                 }
 690                 /*
 691                  * Honour the base load address from the dso if it is
 692                  * non-zero for some reason.
 693                  */
 694                 if (baddr == 0)
 695                         et_dyn_addr = ET_DYN_LOAD_ADDR;
 696                 else
 697                         et_dyn_addr = 0;
 698         } else
 699                 et_dyn_addr = 0;
 700
 701         if (interp != NULL && brand_info->interp_newpath != NULL)
 702                 newinterp = brand_info->interp_newpath;
 703
 704         exec_new_vmspace(imgp, NULL);
 705
 706         /*
 707          * Yeah, I'm paranoid.  There is every reason in the world to get
 708          * VTEXT now since from here on out, there are places we can have
 709          * a context switch.  Better safe than sorry; I really don't want
 710          * the file to change while it's being loaded.
 711          */
 712         vsetflags(imgp->vp, VTEXT);
 713
 714         vmspace = imgp->proc->p_vmspace;
 715
 716         for (i = 0; i < hdr->e_phnum; i++) {
 717                 switch (phdr[i].p_type) {
 718                 case PT_LOAD:   /* Loadable segment */
 719                         if (phdr[i].p_memsz == 0)
 720                                 break;
 721                         prot = __elfN(trans_prot)(phdr[i].p_flags);
 722
 723                         if ((error = __elfN(load_section)(
 724                                         imgp->proc,
 725                                         vmspace,
 726                                         imgp->vp,
 727                                         phdr[i].p_offset,
 728                                         (caddr_t)phdr[i].p_vaddr + et_dyn_addr,
 729                                         phdr[i].p_memsz,
 730                                         phdr[i].p_filesz,
 731                                         prot)) != 0) {
 732                                 if (interp != NULL)
 733                                         kfree (interp, M_TEMP);
 734                                 return (error);
 735                         }
 736
 737                         /*
 738                          * If this segment contains the program headers,
 739                          * remember their virtual address for the AT_PHDR
 740                          * aux entry. Static binaries don't usually include
 741                          * a PT_PHDR entry.
 742                          */
 743                         if (phdr[i].p_offset == 0 &&
 744                             hdr->e_phoff + hdr->e_phnum * hdr->e_phentsize
 745                                 <= phdr[i].p_filesz)
 746                                 proghdr = phdr[i].p_vaddr + hdr->e_phoff +
 747                                     et_dyn_addr;
 748
 749                         seg_addr = trunc_page(phdr[i].p_vaddr + et_dyn_addr);
 750                         seg_size = round_page(phdr[i].p_memsz +
 751                             phdr[i].p_vaddr + et_dyn_addr - seg_addr);
 752
 753                         /*
 754                          * Is this .text or .data?  We can't use
 755                          * VM_PROT_WRITE or VM_PROT_EXEC, it breaks the
 756                          * alpha terribly and possibly does other bad
 757                          * things so we stick to the old way of figuring
 758                          * it out:  If the segment contains the program
 759                          * entry point, it's a text segment, otherwise it
 760                          * is a data segment.
 761                          *
 762                          * Note that obreak() assumes that data_addr +
 763                          * data_size == end of data load area, and the ELF
 764                          * file format expects segments to be sorted by
 765                          * address.  If multiple data segments exist, the
 766                          * last one will be used.
 767                          */
 768                         if (hdr->e_entry >= phdr[i].p_vaddr &&
 769                             hdr->e_entry < (phdr[i].p_vaddr +
 770                             phdr[i].p_memsz)) {
 771                                 text_size = seg_size;
 772                                 text_addr = seg_addr;
 773                                 entry = (u_long)hdr->e_entry + et_dyn_addr;
 774                         } else {
 775                                 data_size = seg_size;
 776                                 data_addr = seg_addr;
 777                         }
 778                         total_size += seg_size;
 779
 780                         /*
 781                          * Check limits.  It should be safe to check the
 782                          * limits after loading the segment since we do
 783                          * not actually fault in all the segment's pages.
 784                          */
 785                         if (data_size >
 786                             imgp->proc->p_rlimit[RLIMIT_DATA].rlim_cur ||
 787                             text_size > maxtsiz ||
 788                             total_size >
 789                             imgp->proc->p_rlimit[RLIMIT_VMEM].rlim_cur) {
 790                                 if (interp != NULL)
 791                                         kfree(interp, M_TEMP);
 792                                 error = ENOMEM;
 793                                 return (error);
 794                         }
 795                         break;
 796                 case PT_PHDR:   /* Program header table info */
 797                         proghdr = phdr[i].p_vaddr + et_dyn_addr;
 798                         break;
 799                 default:
 800                         break;
 801                 }
 802         }
 803
 804         vmspace->vm_tsize = text_size >> PAGE_SHIFT;
 805         vmspace->vm_taddr = (caddr_t)(uintptr_t)text_addr;
 806         vmspace->vm_dsize = data_size >> PAGE_SHIFT;
 807         vmspace->vm_daddr = (caddr_t)(uintptr_t)data_addr;
 808
 809         addr = ELF_RTLD_ADDR(vmspace);
 810
 811         imgp->entry_addr = entry;
 812
 813         imgp->proc->p_sysent = brand_info->sysvec;
 814         EVENTHANDLER_INVOKE(process_exec, imgp);
 815
 816         if (interp != NULL) {
 817                 int have_interp = FALSE;
 818                 if (brand_info->emul_path != NULL &&
 819                     brand_info->emul_path[0] != '\0') {
 820                         path = kmalloc(MAXPATHLEN, M_TEMP, M_WAITOK);
 821                         ksnprintf(path, MAXPATHLEN, "%s%s",
 822                             brand_info->emul_path, interp);
 823                         error = __elfN(load_file)(imgp->proc, path, &addr,
 824                             &imgp->entry_addr);
 825                         kfree(path, M_TEMP);
 826                         if (error == 0)
 827                                 have_interp = TRUE;
 828                 }
 829                 if (!have_interp && newinterp != NULL) {
 830                         error = __elfN(load_file)(imgp->proc, newinterp,
 831                             &addr, &imgp->entry_addr);
 832                         if (error == 0)
 833                                 have_interp = TRUE;
 834                 }
 835                 if (!have_interp) {
 836                         error = __elfN(load_file)(imgp->proc, interp, &addr,
 837                             &imgp->entry_addr);
 838                 }
 839                 if (error != 0) {
 840                         uprintf("ELF interpreter %s not found\n", interp);
 841                         kfree(interp, M_TEMP);
 842                         return (error);
 843                 }
 844                 kfree(interp, M_TEMP);
 845         } else
 846                 addr = et_dyn_addr;
 847
 848         /*
 849          * Construct auxargs table (used by the fixup routine)
 850          */
 851         elf_auxargs = kmalloc(sizeof(Elf_Auxargs), M_TEMP, M_WAITOK);
 852         elf_auxargs->execfd = -1;
 853         elf_auxargs->phdr = proghdr;
 854         elf_auxargs->phent = hdr->e_phentsize;
 855         elf_auxargs->phnum = hdr->e_phnum;
 856         elf_auxargs->pagesz = PAGE_SIZE;
 857         elf_auxargs->base = addr;
 858         elf_auxargs->flags = 0;
 859         elf_auxargs->entry = entry;
 860
 861         imgp->auxargs = elf_auxargs;
 862         imgp->interpreted = 0;
 863         imgp->proc->p_osrel = osrel;
 864
 865         return (error);
 866 }
 867
 868 int
 869 __elfN(dragonfly_fixup)(register_t **stack_base, struct image_params *imgp)
 870 {
 871         Elf_Auxargs *args = (Elf_Auxargs *)imgp->auxargs;
 872         Elf_Addr *base;
 873         Elf_Addr *pos;
 874
 875         base = (Elf_Addr *)*stack_base;
 876         pos = base + (imgp->args->argc + imgp->args->envc + 2);
 877
 878         if (args->execfd != -1)
 879                 AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd);
 880         AUXARGS_ENTRY(pos, AT_PHDR, args->phdr);
 881         AUXARGS_ENTRY(pos, AT_PHENT, args->phent);
 882         AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum);
 883         AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz);
 884         AUXARGS_ENTRY(pos, AT_FLAGS, args->flags);
 885         AUXARGS_ENTRY(pos, AT_ENTRY, args->entry);
 886         AUXARGS_ENTRY(pos, AT_BASE, args->base);
 887         if (imgp->execpathp != 0)
 888                 AUXARGS_ENTRY(pos, AT_EXECPATH, imgp->execpathp);
 889         AUXARGS_ENTRY(pos, AT_OSRELDATE, osreldate);
 890         AUXARGS_ENTRY(pos, AT_NULL, 0);
 891
 892         kfree(imgp->auxargs, M_TEMP);
 893         imgp->auxargs = NULL;
 894
 895         base--;
 896         suword(base, (long)imgp->args->argc);
 897         *stack_base = (register_t *)base;
 898         return (0);
 899 }
 900
 901 /*
 902  * Code for generating ELF core dumps.
 903  */
 904
 905 typedef int (*segment_callback)(vm_map_entry_t, void *);
 906
 907 /* Closure for cb_put_phdr(). */
 908 struct phdr_closure {
 909         Elf_Phdr *phdr;         /* Program header to fill in (incremented) */
 910         Elf_Phdr *phdr_max;     /* Pointer bound for error check */
 911         Elf_Off offset;         /* Offset of segment in core file */
 912 };
 913
 914 /* Closure for cb_size_segment(). */
 915 struct sseg_closure {
 916         int count;              /* Count of writable segments. */
 917         size_t vsize;           /* Total size of all writable segments. */
 918 };
 919
 920 /* Closure for cb_put_fp(). */
 921 struct fp_closure {
 922         struct vn_hdr *vnh;
 923         struct vn_hdr *vnh_max;
 924         int count;
 925         struct stat *sb;
 926 };
 927
 928 typedef struct elf_buf {
 929         char    *buf;
 930         size_t  off;
 931         size_t  off_max;
 932 } *elf_buf_t;
 933
 934 static void *target_reserve(elf_buf_t target, size_t bytes, int *error);
 935
 936 static int cb_put_phdr (vm_map_entry_t, void *);
 937 static int cb_size_segment (vm_map_entry_t, void *);
 938 static int cb_fpcount_segment(vm_map_entry_t, void *);
 939 static int cb_put_fp(vm_map_entry_t, void *);
 940
 941
 942 static int each_segment (struct proc *, segment_callback, void *, int);
 943 static int __elfN(corehdr)(struct lwp *, int, struct file *, struct ucred *,
 944                         int, elf_buf_t);
 945 enum putmode { WRITE, DRYRUN };
 946 static int __elfN(puthdr)(struct lwp *, elf_buf_t, int sig, enum putmode,
 947                         int, struct file *);
 948 static int elf_putallnotes(struct lwp *, elf_buf_t, int, enum putmode);
 949 static int __elfN(putnote)(elf_buf_t, const char *, int, const void *, size_t);
 950
 951 static int elf_putsigs(struct lwp *, elf_buf_t);
 952 static int elf_puttextvp(struct proc *, elf_buf_t);
 953 static int elf_putfiles(struct proc *, elf_buf_t, struct file *);
 954
 955 int
 956 __elfN(coredump)(struct lwp *lp, int sig, struct vnode *vp, off_t limit)
 957 {
 958         struct file *fp;
 959         int error;
 960
 961         if ((error = falloc(NULL, &fp, NULL)) != 0)
 962                 return (error);
 963         fsetcred(fp, lp->lwp_proc->p_ucred);
 964
 965         /*
 966          * XXX fixme.
 967          */
 968         fp->f_type = DTYPE_VNODE;
 969         fp->f_flag = O_CREAT|O_WRONLY|O_NOFOLLOW;
 970         fp->f_ops = &vnode_fileops;
 971         fp->f_data = vp;
 972
 973         error = generic_elf_coredump(lp, sig, fp, limit);
 974
 975         fp->f_type = 0;
 976         fp->f_flag = 0;
 977         fp->f_ops = &badfileops;
 978         fp->f_data = NULL;
 979         fdrop(fp);
 980         return (error);
 981 }
 982
 983 int
 984 generic_elf_coredump(struct lwp *lp, int sig, struct file *fp, off_t limit)
 985 {
 986         struct proc *p = lp->lwp_proc;
 987         struct ucred *cred = p->p_ucred;
 988         int error = 0;
 989         struct sseg_closure seginfo;
 990         struct elf_buf target;
 991
 992         if (!fp)
 993                 kprintf("can't dump core - null fp\n");
 994
 995         /*
 996          * Size the program segments
 997          */
 998         seginfo.count = 0;
 999         seginfo.vsize = 0;
1000         each_segment(p, cb_size_segment, &seginfo, 1);
1001
1002         /*
1003          * Calculate the size of the core file header area by making
1004          * a dry run of generating it.  Nothing is written, but the
1005          * size is calculated.
1006          */
1007         bzero(&target, sizeof(target));
1008         __elfN(puthdr)(lp, &target, sig, DRYRUN, seginfo.count, fp);
1009
1010         if (target.off + seginfo.vsize >= limit)
1011                 return (EFAULT);
1012
1013         /*
1014          * Allocate memory for building the header, fill it up,
1015          * and write it out.
1016          */
1017         target.off_max = target.off;
1018         target.off = 0;
1019         target.buf = kmalloc(target.off_max, M_TEMP, M_WAITOK|M_ZERO);
1020
1021         error = __elfN(corehdr)(lp, sig, fp, cred, seginfo.count, &target);
1022
1023         /* Write the contents of all of the writable segments. */
1024         if (error == 0) {
1025                 Elf_Phdr *php;
1026                 int i;
1027                 ssize_t nbytes;
1028
1029                 php = (Elf_Phdr *)(target.buf + sizeof(Elf_Ehdr)) + 1;
1030                 for (i = 0; i < seginfo.count; i++) {
1031                         error = fp_write(fp, (caddr_t)php->p_vaddr,
1032                                         php->p_filesz, &nbytes, UIO_USERSPACE);
1033                         if (error != 0)
1034                                 break;
1035                         php++;
1036                 }
1037         }
1038         kfree(target.buf, M_TEMP);
1039
1040         return (error);
1041 }
1042
1043 /*
1044  * A callback for each_segment() to write out the segment's
1045  * program header entry.
1046  */
1047 static int
1048 cb_put_phdr(vm_map_entry_t entry, void *closure)
1049 {
1050         struct phdr_closure *phc = closure;
1051         Elf_Phdr *phdr = phc->phdr;
1052
1053         if (phc->phdr == phc->phdr_max)
1054                 return (EINVAL);
1055
1056         phc->offset = round_page(phc->offset);
1057
1058         phdr->p_type = PT_LOAD;
1059         phdr->p_offset = phc->offset;
1060         phdr->p_vaddr = entry->start;
1061         phdr->p_paddr = 0;
1062         phdr->p_filesz = phdr->p_memsz = entry->end - entry->start;
1063         phdr->p_align = PAGE_SIZE;
1064         phdr->p_flags = __elfN(untrans_prot)(entry->protection);
1065
1066         phc->offset += phdr->p_filesz;
1067         ++phc->phdr;
1068         return (0);
1069 }
1070
1071 /*
1072  * A callback for each_writable_segment() to gather information about
1073  * the number of segments and their total size.
1074  */
1075 static int
1076 cb_size_segment(vm_map_entry_t entry, void *closure)
1077 {
1078         struct sseg_closure *ssc = closure;
1079
1080         ++ssc->count;
1081         ssc->vsize += entry->end - entry->start;
1082         return (0);
1083 }
1084
1085 /*
1086  * A callback for each_segment() to gather information about
1087  * the number of text segments.
1088  */
1089 static int
1090 cb_fpcount_segment(vm_map_entry_t entry, void *closure)
1091 {
1092         int *count = closure;
1093         struct vnode *vp;
1094
1095         if (entry->object.vm_object->type == OBJT_VNODE) {
1096                 vp = (struct vnode *)entry->object.vm_object->handle;
1097                 if ((vp->v_flag & VCKPT) && curproc->p_textvp == vp)
1098                         return (0);
1099                 ++*count;
1100         }
1101         return (0);
1102 }
1103
1104 static int
1105 cb_put_fp(vm_map_entry_t entry, void *closure)
1106 {
1107         struct fp_closure *fpc = closure;
1108         struct vn_hdr *vnh = fpc->vnh;
1109         Elf_Phdr *phdr = &vnh->vnh_phdr;
1110         struct vnode *vp;
1111         int error;
1112
1113         /*
1114          * If an entry represents a vnode then write out a file handle.
1115          *
1116          * If we are checkpointing a checkpoint-restored program we do
1117          * NOT record the filehandle for the old checkpoint vnode (which
1118          * is mapped all over the place).  Instead we rely on the fact
1119          * that a checkpoint-restored program does not mmap() the checkpt
1120          * vnode NOCORE, so its contents will be written out to the
1121          * new checkpoint file.  This is necessary because the 'old'
1122          * checkpoint file is typically destroyed when a new one is created
1123          * and thus cannot be used to restore the new checkpoint.
1124          *
1125          * Theoretically we could create a chain of checkpoint files and
1126          * operate the checkpointing operation kinda like an incremental
1127          * checkpoint, but a checkpoint restore would then likely wind up
1128          * referencing many prior checkpoint files and that is a bit over
1129          * the top for the purpose of the checkpoint API.
1130          */
1131         if (entry->object.vm_object->type == OBJT_VNODE) {
1132                 vp = (struct vnode *)entry->object.vm_object->handle;
1133                 if ((vp->v_flag & VCKPT) && curproc->p_textvp == vp)
1134                         return (0);
1135                 if (vnh == fpc->vnh_max)
1136                         return (EINVAL);
1137
1138                 if (vp->v_mount)
1139                         vnh->vnh_fh.fh_fsid = vp->v_mount->mnt_stat.f_fsid;
1140                 error = VFS_VPTOFH(vp, &vnh->vnh_fh.fh_fid);
1141                 if (error) {
1142                         char *freepath, *fullpath;
1143
1144                         if (vn_fullpath(curproc, vp, &fullpath, &freepath, 0)) {
1145                                 kprintf("Warning: coredump, error %d: cannot store file handle for vnode %p\n", error, vp);
1146                         } else {
1147                                 kprintf("Warning: coredump, error %d: cannot store file handle for %s\n", error, fullpath);
1148                                 kfree(freepath, M_TEMP);
1149                         }
1150                         error = 0;
1151                 }
1152
1153                 phdr->p_type = PT_LOAD;
1154                 phdr->p_offset = 0;        /* not written to core */
1155                 phdr->p_vaddr = entry->start;
1156                 phdr->p_paddr = 0;
1157                 phdr->p_filesz = phdr->p_memsz = entry->end - entry->start;
1158                 phdr->p_align = PAGE_SIZE;
1159                 phdr->p_flags = 0;
1160                 if (entry->protection & VM_PROT_READ)
1161                         phdr->p_flags |= PF_R;
1162                 if (entry->protection & VM_PROT_WRITE)
1163                         phdr->p_flags |= PF_W;
1164                 if (entry->protection & VM_PROT_EXECUTE)
1165                         phdr->p_flags |= PF_X;
1166                 ++fpc->vnh;
1167                 ++fpc->count;
1168         }
1169         return (0);
1170 }
1171
1172 /*
1173  * For each writable segment in the process's memory map, call the given
1174  * function with a pointer to the map entry and some arbitrary
1175  * caller-supplied data.
1176  */
1177 static int
1178 each_segment(struct proc *p, segment_callback func, void *closure, int writable)
1179 {
1180         int error = 0;
1181         vm_map_t map = &p->p_vmspace->vm_map;
1182         vm_map_entry_t entry;
1183
1184         for (entry = map->header.next; error == 0 && entry != &map->header;
1185             entry = entry->next) {
1186                 vm_object_t obj;
1187                 vm_object_t lobj;
1188                 vm_object_t tobj;
1189
1190                 /*
1191                  * Don't dump inaccessible mappings, deal with legacy
1192                  * coredump mode.
1193                  *
1194                  * Note that read-only segments related to the elf binary
1195                  * are marked MAP_ENTRY_NOCOREDUMP now so we no longer
1196                  * need to arbitrarily ignore such segments.
1197                  */
1198                 if (elf_legacy_coredump) {
1199                         if (writable && (entry->protection & VM_PROT_RW) != VM_PROT_RW)
1200                                 continue;
1201                 } else {
1202                         if (writable && (entry->protection & VM_PROT_ALL) == 0)
1203                                 continue;
1204                 }
1205
1206                 /*
1207                  * Dont include memory segment in the coredump if
1208                  * MAP_NOCORE is set in mmap(2) or MADV_NOCORE in
1209                  * madvise(2).
1210                  *
1211                  * Currently we only dump normal VM object maps.  We do
1212                  * not dump submaps or virtual page tables.
1213                  */
1214                 if (writable && (entry->eflags & MAP_ENTRY_NOCOREDUMP))
1215                         continue;
1216                 if (entry->maptype != VM_MAPTYPE_NORMAL)
1217                         continue;
1218                 if ((obj = entry->object.vm_object) == NULL)
1219                         continue;
1220
1221                 /*
1222                  * Find the bottom-most object, leaving the base object
1223                  * and the bottom-most object held (but only one hold
1224                  * if they happen to be the same).
1225                  */
1226                 vm_object_hold_shared(obj);
1227
1228                 lobj = obj;
1229                 while (lobj && (tobj = lobj->backing_object) != NULL) {
1230                         KKASSERT(tobj != obj);
1231                         vm_object_hold_shared(tobj);
1232                         if (tobj == lobj->backing_object) {
1233                                 if (lobj != obj) {
1234                                         vm_object_lock_swap();
1235                                         vm_object_drop(lobj);
1236                                 }
1237                                 lobj = tobj;
1238                         } else {
1239                                 vm_object_drop(tobj);
1240                         }
1241                 }
1242
1243                 /*
1244                  * The callback only applies to default, swap, or vnode
1245                  * objects.  Other types of objects such as memory-mapped
1246                  * devices are ignored.
1247                  */
1248                 if (lobj->type == OBJT_DEFAULT || lobj->type == OBJT_SWAP ||
1249                     lobj->type == OBJT_VNODE) {
1250                         error = (*func)(entry, closure);
1251                 }
1252                 if (lobj != obj)
1253                         vm_object_drop(lobj);
1254                 vm_object_drop(obj);
1255         }
1256         return (error);
1257 }
1258
1259 static
1260 void *
1261 target_reserve(elf_buf_t target, size_t bytes, int *error)
1262 {
1263     void *res = NULL;
1264
1265     if (target->buf) {
1266             if (target->off + bytes > target->off_max)
1267                     *error = EINVAL;
1268             else
1269                     res = target->buf + target->off;
1270     }
1271     target->off += bytes;
1272     return (res);
1273 }
1274
1275 /*
1276  * Write the core file header to the file, including padding up to
1277  * the page boundary.
1278  */
1279 static int
1280 __elfN(corehdr)(struct lwp *lp, int sig, struct file *fp, struct ucred *cred,
1281             int numsegs, elf_buf_t target)
1282 {
1283         int error;
1284         ssize_t nbytes;
1285
1286         /*
1287          * Fill in the header.  The fp is passed so we can detect and flag
1288          * a checkpoint file pointer within the core file itself, because
1289          * it may not be restored from the same file handle.
1290          */
1291         error = __elfN(puthdr)(lp, target, sig, WRITE, numsegs, fp);
1292
1293         /* Write it to the core file. */
1294         if (error == 0) {
1295                 error = fp_write(fp, target->buf, target->off, &nbytes,
1296                                  UIO_SYSSPACE);
1297         }
1298         return (error);
1299 }
1300
1301 static int
1302 __elfN(puthdr)(struct lwp *lp, elf_buf_t target, int sig, enum putmode mode,
1303     int numsegs, struct file *fp)
1304 {
1305         struct proc *p = lp->lwp_proc;
1306         int error = 0;
1307         size_t phoff;
1308         size_t noteoff;
1309         size_t notesz;
1310         Elf_Ehdr *ehdr;
1311         Elf_Phdr *phdr;
1312
1313         ehdr = target_reserve(target, sizeof(Elf_Ehdr), &error);
1314
1315         phoff = target->off;
1316         phdr = target_reserve(target, (numsegs + 1) * sizeof(Elf_Phdr), &error);
1317
1318         noteoff = target->off;
1319         if (error == 0)
1320                 elf_putallnotes(lp, target, sig, mode);
1321         notesz = target->off - noteoff;
1322
1323         /*
1324          * put extra cruft for dumping process state here
1325          *  - we really want it be before all the program
1326          *    mappings
1327          *  - we just need to update the offset accordingly
1328          *    and GDB will be none the wiser.
1329          */
1330         if (error == 0)
1331                 error = elf_puttextvp(p, target);
1332         if (error == 0)
1333                 error = elf_putsigs(lp, target);
1334         if (error == 0)
1335                 error = elf_putfiles(p, target, fp);
1336
1337         /*
1338          * Align up to a page boundary for the program segments.  The
1339          * actual data will be written to the outptu file, not to elf_buf_t,
1340          * so we do not have to do any further bounds checking.
1341          */
1342         target->off = round_page(target->off);
1343         if (error == 0 && ehdr != NULL) {
1344                 /*
1345                  * Fill in the ELF header.
1346                  */
1347                 ehdr->e_ident[EI_MAG0] = ELFMAG0;
1348                 ehdr->e_ident[EI_MAG1] = ELFMAG1;
1349                 ehdr->e_ident[EI_MAG2] = ELFMAG2;
1350                 ehdr->e_ident[EI_MAG3] = ELFMAG3;
1351                 ehdr->e_ident[EI_CLASS] = ELF_CLASS;
1352                 ehdr->e_ident[EI_DATA] = ELF_DATA;
1353                 ehdr->e_ident[EI_VERSION] = EV_CURRENT;
1354                 ehdr->e_ident[EI_OSABI] = ELFOSABI_NONE;
1355                 ehdr->e_ident[EI_ABIVERSION] = 0;
1356                 ehdr->e_ident[EI_PAD] = 0;
1357                 ehdr->e_type = ET_CORE;
1358                 ehdr->e_machine = ELF_ARCH;
1359                 ehdr->e_version = EV_CURRENT;
1360                 ehdr->e_entry = 0;
1361                 ehdr->e_phoff = phoff;
1362                 ehdr->e_flags = 0;
1363                 ehdr->e_ehsize = sizeof(Elf_Ehdr);
1364                 ehdr->e_phentsize = sizeof(Elf_Phdr);
1365                 ehdr->e_phnum = numsegs + 1;
1366                 ehdr->e_shentsize = sizeof(Elf_Shdr);
1367                 ehdr->e_shnum = 0;
1368                 ehdr->e_shstrndx = SHN_UNDEF;
1369         }
1370         if (error == 0 && phdr != NULL) {
1371                 /*
1372                  * Fill in the program header entries.
1373                  */
1374                 struct phdr_closure phc;
1375
1376                 /* The note segement. */
1377                 phdr->p_type = PT_NOTE;
1378                 phdr->p_offset = noteoff;
1379                 phdr->p_vaddr = 0;
1380                 phdr->p_paddr = 0;
1381                 phdr->p_filesz = notesz;
1382                 phdr->p_memsz = 0;
1383                 phdr->p_flags = 0;
1384                 phdr->p_align = 0;
1385                 ++phdr;
1386
1387                 /* All the writable segments from the program. */
1388                 phc.phdr = phdr;
1389                 phc.phdr_max = phdr + numsegs;
1390                 phc.offset = target->off;
1391                 each_segment(p, cb_put_phdr, &phc, 1);
1392         }
1393         return (error);
1394 }
1395
1396 /*
1397  * Append core dump notes to target ELF buffer or simply update target size
1398  * if dryrun selected.
1399  */
1400 static int
1401 elf_putallnotes(struct lwp *corelp, elf_buf_t target, int sig,
1402     enum putmode mode)
1403 {
1404         struct proc *p = corelp->lwp_proc;
1405         int error;
1406         struct {
1407                 prstatus_t status;
1408                 prfpregset_t fpregs;
1409                 prpsinfo_t psinfo;
1410         } *tmpdata;
1411         prstatus_t *status;
1412         prfpregset_t *fpregs;
1413         prpsinfo_t *psinfo;
1414         struct lwp *lp;
1415
1416         /*
1417          * Allocate temporary storage for notes on heap to avoid stack overflow.
1418          */
1419         if (mode != DRYRUN) {
1420                 tmpdata = kmalloc(sizeof(*tmpdata), M_TEMP, M_ZERO | M_WAITOK);
1421                 status = &tmpdata->status;
1422                 fpregs = &tmpdata->fpregs;
1423                 psinfo = &tmpdata->psinfo;
1424         } else {
1425                 tmpdata = NULL;
1426                 status = NULL;
1427                 fpregs = NULL;
1428                 psinfo = NULL;
1429         }
1430
1431         /*
1432          * Append LWP-agnostic note.
1433          */
1434         if (mode != DRYRUN) {
1435                 psinfo->pr_version = PRPSINFO_VERSION;
1436                 psinfo->pr_psinfosz = sizeof(prpsinfo_t);
1437                 strlcpy(psinfo->pr_fname, p->p_comm,
1438                         sizeof(psinfo->pr_fname));
1439                 /*
1440                  * XXX - We don't fill in the command line arguments
1441                  * properly yet.
1442                  */
1443                 strlcpy(psinfo->pr_psargs, p->p_comm,
1444                         sizeof(psinfo->pr_psargs));
1445         }
1446         error =
1447             __elfN(putnote)(target, "CORE", NT_PRPSINFO, psinfo, sizeof *psinfo);
1448         if (error)
1449                 goto exit;
1450
1451         /*
1452          * Append first note for LWP that triggered core so that it is
1453          * the selected one when the debugger starts.
1454          */
1455         if (mode != DRYRUN) {
1456                 status->pr_version = PRSTATUS_VERSION;
1457                 status->pr_statussz = sizeof(prstatus_t);
1458                 status->pr_gregsetsz = sizeof(gregset_t);
1459                 status->pr_fpregsetsz = sizeof(fpregset_t);
1460                 status->pr_osreldate = osreldate;
1461                 status->pr_cursig = sig;
1462                 /*
1463                  * XXX GDB needs unique pr_pid for each LWP and does not
1464                  * not support pr_pid==0 but lwp_tid can be 0, so hack unique
1465                  * value.
1466                  */
1467                 status->pr_pid = corelp->lwp_tid;
1468                 fill_regs(corelp, &status->pr_reg);
1469                 fill_fpregs(corelp, fpregs);
1470         }
1471         error =
1472             __elfN(putnote)(target, "CORE", NT_PRSTATUS, status, sizeof *status);
1473         if (error)
1474                 goto exit;
1475         error =
1476             __elfN(putnote)(target, "CORE", NT_FPREGSET, fpregs, sizeof *fpregs);
1477         if (error)
1478                 goto exit;
1479
1480         /*
1481          * Then append notes for other LWPs.
1482          */
1483         FOREACH_LWP_IN_PROC(lp, p) {
1484                 if (lp == corelp)
1485                         continue;
1486                 /* skip lwps being created */
1487                 if (lp->lwp_thread == NULL)
1488                         continue;
1489                 if (mode != DRYRUN) {
1490                         status->pr_pid = lp->lwp_tid;
1491                         fill_regs(lp, &status->pr_reg);
1492                         fill_fpregs(lp, fpregs);
1493                 }
1494                 error = __elfN(putnote)(target, "CORE", NT_PRSTATUS,
1495                                         status, sizeof *status);
1496                 if (error)
1497                         goto exit;
1498                 error = __elfN(putnote)(target, "CORE", NT_FPREGSET,
1499                                         fpregs, sizeof *fpregs);
1500                 if (error)
1501                         goto exit;
1502         }
1503
1504 exit:
1505         if (tmpdata != NULL)
1506                 kfree(tmpdata, M_TEMP);
1507         return (error);
1508 }
1509
1510 /*
1511  * Generate a note sub-structure.
1512  *
1513  * NOTE: 4-byte alignment.
1514  */
1515 static int
1516 __elfN(putnote)(elf_buf_t target, const char *name, int type,
1517             const void *desc, size_t descsz)
1518 {
1519         int error = 0;
1520         char *dst;
1521         Elf_Note note;
1522
1523         note.n_namesz = strlen(name) + 1;
1524         note.n_descsz = descsz;
1525         note.n_type = type;
1526         dst = target_reserve(target, sizeof(note), &error);
1527         if (dst != NULL)
1528                 bcopy(&note, dst, sizeof note);
1529         dst = target_reserve(target, note.n_namesz, &error);
1530         if (dst != NULL)
1531                 bcopy(name, dst, note.n_namesz);
1532         target->off = roundup2(target->off, sizeof(Elf_Word));
1533         dst = target_reserve(target, note.n_descsz, &error);
1534         if (dst != NULL)
1535                 bcopy(desc, dst, note.n_descsz);
1536         target->off = roundup2(target->off, sizeof(Elf_Word));
1537         return (error);
1538 }
1539
1540
1541 static int
1542 elf_putsigs(struct lwp *lp, elf_buf_t target)
1543 {
1544         /* XXX lwp handle more than one lwp */
1545         struct proc *p = lp->lwp_proc;
1546         int error = 0;
1547         struct ckpt_siginfo *csi;
1548
1549         csi = target_reserve(target, sizeof(struct ckpt_siginfo), &error);
1550         if (csi) {
1551                 csi->csi_ckptpisz = sizeof(struct ckpt_siginfo);
1552                 bcopy(p->p_sigacts, &csi->csi_sigacts, sizeof(*p->p_sigacts));
1553                 bcopy(&p->p_realtimer, &csi->csi_itimerval, sizeof(struct itimerval));
1554                 bcopy(&lp->lwp_sigmask, &csi->csi_sigmask,
1555                         sizeof(sigset_t));
1556                 csi->csi_sigparent = p->p_sigparent;
1557         }
1558         return (error);
1559 }
1560
1561 static int
1562 elf_putfiles(struct proc *p, elf_buf_t target, struct file *ckfp)
1563 {
1564         int error = 0;
1565         int i;
1566         struct ckpt_filehdr *cfh = NULL;
1567         struct ckpt_fileinfo *cfi;
1568         struct file *fp;
1569         struct vnode *vp;
1570         /*
1571          * the duplicated loop is gross, but it was the only way
1572          * to eliminate uninitialized variable warnings
1573          */
1574         cfh = target_reserve(target, sizeof(struct ckpt_filehdr), &error);
1575         if (cfh) {
1576                 cfh->cfh_nfiles = 0;
1577         }
1578
1579         /*
1580          * ignore STDIN/STDERR/STDOUT.
1581          */
1582         for (i = 3; error == 0 && i < p->p_fd->fd_nfiles; i++) {
1583                 fp = holdfp(p->p_fd, i, -1);
1584                 if (fp == NULL)
1585                         continue;
1586                 /*
1587                  * XXX Only checkpoint vnodes for now.
1588                  */
1589                 if (fp->f_type != DTYPE_VNODE) {
1590                         fdrop(fp);
1591                         continue;
1592                 }
1593                 cfi = target_reserve(target, sizeof(struct ckpt_fileinfo),
1594                                         &error);
1595                 if (cfi == NULL) {
1596                         fdrop(fp);
1597                         continue;
1598                 }
1599                 cfi->cfi_index = -1;
1600                 cfi->cfi_type = fp->f_type;
1601                 cfi->cfi_flags = fp->f_flag;
1602                 cfi->cfi_offset = fp->f_offset;
1603                 cfi->cfi_ckflags = 0;
1604
1605                 if (fp == ckfp)
1606                         cfi->cfi_ckflags |= CKFIF_ISCKPTFD;
1607                 /* f_count and f_msgcount should not be saved/restored */
1608                 /* XXX save cred info */
1609
1610                 switch(fp->f_type) {
1611                 case DTYPE_VNODE:
1612                         vp = (struct vnode *)fp->f_data;
1613                         /*
1614                          * it looks like a bug in ptrace is marking
1615                          * a non-vnode as a vnode - until we find the
1616                          * root cause this will at least prevent
1617                          * further panics from truss
1618                          */
1619                         if (vp == NULL || vp->v_mount == NULL)
1620                                 break;
1621                         cfh->cfh_nfiles++;
1622                         cfi->cfi_index = i;
1623                         cfi->cfi_fh.fh_fsid = vp->v_mount->mnt_stat.f_fsid;
1624                         error = VFS_VPTOFH(vp, &cfi->cfi_fh.fh_fid);
1625                         break;
1626                 default:
1627                         break;
1628                 }
1629                 fdrop(fp);
1630         }
1631         return (error);
1632 }
1633
1634 static int
1635 elf_puttextvp(struct proc *p, elf_buf_t target)
1636 {
1637         int error = 0;
1638         int *vn_count;
1639         struct fp_closure fpc;
1640         struct ckpt_vminfo *vminfo;
1641
1642         vminfo = target_reserve(target, sizeof(struct ckpt_vminfo), &error);
1643         if (vminfo != NULL) {
1644                 vminfo->cvm_dsize = p->p_vmspace->vm_dsize;
1645                 vminfo->cvm_tsize = p->p_vmspace->vm_tsize;
1646                 vminfo->cvm_daddr = p->p_vmspace->vm_daddr;
1647                 vminfo->cvm_taddr = p->p_vmspace->vm_taddr;
1648         }
1649
1650         fpc.count = 0;
1651         vn_count = target_reserve(target, sizeof(int), &error);
1652         if (target->buf != NULL) {
1653                 fpc.vnh = (struct vn_hdr *)(target->buf + target->off);
1654                 fpc.vnh_max = fpc.vnh +
1655                         (target->off_max - target->off) / sizeof(struct vn_hdr);
1656                 error = each_segment(p, cb_put_fp, &fpc, 0);
1657                 if (vn_count)
1658                         *vn_count = fpc.count;
1659         } else {
1660                 error = each_segment(p, cb_fpcount_segment, &fpc.count, 0);
1661         }
1662         target->off += fpc.count * sizeof(struct vn_hdr);
1663         return (error);
1664 }
1665
1666 /*
1667  * Try to find the appropriate ABI-note section for checknote,
1668  * The entire image is searched if necessary, not only the first page.
1669  */
1670 static boolean_t
1671 __elfN(check_note)(struct image_params *imgp, Elf_Brandnote *checknote,
1672     int32_t *osrel)
1673 {
1674         boolean_t valid_note_found;
1675         const Elf_Phdr *phdr, *pnote;
1676         const Elf_Ehdr *hdr;
1677         int i;
1678
1679         valid_note_found = FALSE;
1680         hdr = (const Elf_Ehdr *)imgp->image_header;
1681         phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff);
1682
1683         for (i = 0; i < hdr->e_phnum; i++) {
1684                 if (phdr[i].p_type == PT_NOTE) {
1685                         pnote = &phdr[i];
1686                         valid_note_found = check_PT_NOTE (imgp, checknote,
1687                                 osrel, pnote);
1688                         if (valid_note_found)
1689                                 break;
1690                 }
1691         }
1692         return valid_note_found;
1693 }
1694
1695 /*
1696  * Be careful not to create new overflow conditions when checking
1697  * for overflow.
1698  */
1699 static boolean_t
1700 note_overflow(const Elf_Note *note, size_t maxsize)
1701 {
1702         if (sizeof(*note) > maxsize)
1703                 return TRUE;
1704         if (note->n_namesz > maxsize - sizeof(*note))
1705                 return TRUE;
1706         return FALSE;
1707 }
1708
1709 static boolean_t
1710 hdr_overflow(__ElfN(Off) off_beg, __ElfN(Size) size)
1711 {
1712         __ElfN(Off) off_end;
1713
1714         off_end = off_beg + size;
1715         if (off_end < off_beg)
1716                 return TRUE;
1717         return FALSE;
1718 }
1719
1720 static boolean_t
1721 check_PT_NOTE(struct image_params *imgp, Elf_Brandnote *checknote,
1722               int32_t *osrel, const Elf_Phdr * pnote)
1723 {
1724         boolean_t limited_to_first_page;
1725         boolean_t found = FALSE;
1726         const Elf_Note *note, *note0, *note_end;
1727         const char *note_name;
1728         __ElfN(Off) noteloc, firstloc;
1729         __ElfN(Size) notesz, firstlen, endbyte;
1730         struct lwbuf *lwb;
1731         struct lwbuf lwb_cache;
1732         const char *page;
1733         char *data = NULL;
1734         int n;
1735
1736         if (hdr_overflow(pnote->p_offset, pnote->p_filesz))
1737                 return (FALSE);
1738         notesz = pnote->p_filesz;
1739         noteloc = pnote->p_offset;
1740         endbyte = noteloc + notesz;
1741         limited_to_first_page = noteloc < PAGE_SIZE && endbyte < PAGE_SIZE;
1742
1743         if (limited_to_first_page) {
1744                 note = (const Elf_Note *)(imgp->image_header + noteloc);
1745                 note_end = (const Elf_Note *)(imgp->image_header + endbyte);
1746                 note0 = note;
1747         } else {
1748                 firstloc = noteloc & PAGE_MASK;
1749                 firstlen = PAGE_SIZE - firstloc;
1750                 if (notesz < sizeof(Elf_Note) || notesz > PAGE_SIZE)
1751                         return (FALSE);
1752
1753                 lwb = &lwb_cache;
1754                 if (exec_map_page(imgp, noteloc >> PAGE_SHIFT, &lwb, &page))
1755                         return (FALSE);
1756                 if (firstlen < notesz) {         /* crosses page boundary */
1757                         data = kmalloc(notesz, M_TEMP, M_WAITOK);
1758                         bcopy(page + firstloc, data, firstlen);
1759
1760                         exec_unmap_page(lwb);
1761                         lwb = &lwb_cache;
1762                         if (exec_map_page(imgp, (noteloc >> PAGE_SHIFT) + 1,
1763                                 &lwb, &page)) {
1764                                 kfree(data, M_TEMP);
1765                                 return (FALSE);
1766                         }
1767                         bcopy(page, data + firstlen, notesz - firstlen);
1768                         note = note0 = (const Elf_Note *)(data);
1769                         note_end = (const Elf_Note *)(data + notesz);
1770                 } else {
1771                         note = note0 = (const Elf_Note *)(page + firstloc);
1772                         note_end = (const Elf_Note *)(page + firstloc +
1773                                 firstlen);
1774                 }
1775         }
1776
1777         for (n = 0; n < 100 && note >= note0 && note < note_end; n++) {
1778                 if (!aligned(note, Elf32_Addr))
1779                         break;
1780                 if (note_overflow(note, (const char *)note_end -
1781                                         (const char *)note)) {
1782                         break;
1783                 }
1784                 note_name = (const char *)(note + 1);
1785
1786                 if (note->n_namesz == checknote->hdr.n_namesz
1787                     && note->n_descsz == checknote->hdr.n_descsz
1788                     && note->n_type == checknote->hdr.n_type
1789                     && (strncmp(checknote->vendor, note_name,
1790                         checknote->hdr.n_namesz) == 0)) {
1791                         /* Fetch osreldata from ABI.note-tag */
1792                         if ((checknote->flags & BN_TRANSLATE_OSREL) != 0 &&
1793                             checknote->trans_osrel != NULL)
1794                                 checknote->trans_osrel(note, osrel);
1795                         found = TRUE;
1796                         break;
1797                 }
1798                 note = (const Elf_Note *)((const char *)(note + 1) +
1799                     roundup2(note->n_namesz, sizeof(Elf32_Addr)) +
1800                     roundup2(note->n_descsz, sizeof(Elf32_Addr)));
1801         }
1802
1803         if (!limited_to_first_page) {
1804                 if (data != NULL)
1805                         kfree(data, M_TEMP);
1806                 exec_unmap_page(lwb);
1807         }
1808         return (found);
1809 }
1810
1811 /*
1812  * The interpreter program header may be located beyond the first page, so
1813  * regardless of its location, a copy of the interpreter path is created so
1814  * that it may be safely referenced by the calling function in all case.  The
1815  * memory is allocated by calling function, and the copying is done here.
1816  */
1817 static boolean_t
1818 extract_interpreter(struct image_params *imgp, const Elf_Phdr *pinterpreter,
1819                     char *data)
1820 {
1821         boolean_t limited_to_first_page;
1822         const boolean_t result_success = FALSE;
1823         const boolean_t result_failure = TRUE;
1824         __ElfN(Off) pathloc, firstloc;
1825         __ElfN(Size) pathsz, firstlen, endbyte;
1826         struct lwbuf *lwb;
1827         struct lwbuf lwb_cache;
1828         const char *page;
1829
1830         if (hdr_overflow(pinterpreter->p_offset, pinterpreter->p_filesz))
1831                 return (result_failure);
1832         pathsz  = pinterpreter->p_filesz;
1833         pathloc = pinterpreter->p_offset;
1834         endbyte = pathloc + pathsz;
1835
1836         limited_to_first_page = pathloc < PAGE_SIZE && endbyte < PAGE_SIZE;
1837         if (limited_to_first_page) {
1838                 bcopy(imgp->image_header + pathloc, data, pathsz);
1839                 return (result_success);
1840         }
1841
1842         firstloc = pathloc & PAGE_MASK;
1843         firstlen = PAGE_SIZE - firstloc;
1844
1845         lwb = &lwb_cache;
1846         if (exec_map_page(imgp, pathloc >> PAGE_SHIFT, &lwb, &page))
1847                 return (result_failure);
1848
1849         if (firstlen < pathsz) {         /* crosses page boundary */
1850                 bcopy(page + firstloc, data, firstlen);
1851
1852                 exec_unmap_page(lwb);
1853                 lwb = &lwb_cache;
1854                 if (exec_map_page(imgp, (pathloc >> PAGE_SHIFT) + 1, &lwb,
1855                         &page))
1856                         return (result_failure);
1857                 bcopy(page, data + firstlen, pathsz - firstlen);
1858         } else
1859                 bcopy(page + firstloc, data, pathsz);
1860
1861         exec_unmap_page(lwb);
1862         return (result_success);
1863 }
1864
1865 static boolean_t
1866 __elfN(bsd_trans_osrel)(const Elf_Note *note, int32_t *osrel)
1867 {
1868         uintptr_t p;
1869
1870         p = (uintptr_t)(note + 1);
1871         p += roundup2(note->n_namesz, sizeof(Elf32_Addr));
1872         *osrel = *(const int32_t *)(p);
1873
1874         return (TRUE);
1875 }
1876
1877 /*
1878  * Tell kern_execve.c about it, with a little help from the linker.
1879  */
1880 #if defined(__x86_64__)
1881 static struct execsw elf_execsw = {exec_elf64_imgact, "ELF64"};
1882 EXEC_SET_ORDERED(elf64, elf_execsw, SI_ORDER_FIRST);
1883 #else /* i386 assumed */
1884 static struct execsw elf_execsw = {exec_elf32_imgact, "ELF32"};
1885 EXEC_SET_ORDERED(elf32, elf_execsw, SI_ORDER_FIRST);
1886 #endif
1887
1888 static vm_prot_t
1889 __elfN(trans_prot)(Elf_Word flags)
1890 {
1891         vm_prot_t prot;
1892
1893         prot = 0;
1894         if (flags & PF_X)
1895                 prot |= VM_PROT_EXECUTE;
1896         if (flags & PF_W)
1897                 prot |= VM_PROT_WRITE;
1898         if (flags & PF_R)
1899                 prot |= VM_PROT_READ;
1900         return (prot);
1901 }
1902
1903 static Elf_Word
1904 __elfN(untrans_prot)(vm_prot_t prot)
1905 {
1906         Elf_Word flags;
1907
1908         flags = 0;
1909         if (prot & VM_PROT_EXECUTE)
1910                 flags |= PF_X;
1911         if (prot & VM_PROT_READ)
1912                 flags |= PF_R;
1913         if (prot & VM_PROT_WRITE)
1914                 flags |= PF_W;
1915         return (flags);
1916 }