xref: /dragonfly/sys/kern/imgact_elf.c (revision c3762235)
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 }
1917