xref: /freebsd/sys/kern/imgact_elf.c (revision 52c2bb75163559a6e2866ad374a7de67a4ea1273)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 2017 Dell EMC
5  * Copyright (c) 2000-2001, 2003 David O'Brien
6  * Copyright (c) 1995-1996 Søren Schmidt
7  * Copyright (c) 1996 Peter Wemm
8  * All rights reserved.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer
15  *    in this position and unchanged.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. The name of the author may not be used to endorse or promote products
20  *    derived from this software without specific prior written permission
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
36 
37 #include "opt_capsicum.h"
38 
39 #include <sys/param.h>
40 #include <sys/capsicum.h>
41 #include <sys/compressor.h>
42 #include <sys/exec.h>
43 #include <sys/fcntl.h>
44 #include <sys/imgact.h>
45 #include <sys/imgact_elf.h>
46 #include <sys/jail.h>
47 #include <sys/kernel.h>
48 #include <sys/lock.h>
49 #include <sys/malloc.h>
50 #include <sys/mount.h>
51 #include <sys/mman.h>
52 #include <sys/namei.h>
53 #include <sys/pioctl.h>
54 #include <sys/proc.h>
55 #include <sys/procfs.h>
56 #include <sys/ptrace.h>
57 #include <sys/racct.h>
58 #include <sys/resourcevar.h>
59 #include <sys/rwlock.h>
60 #include <sys/sbuf.h>
61 #include <sys/sf_buf.h>
62 #include <sys/smp.h>
63 #include <sys/systm.h>
64 #include <sys/signalvar.h>
65 #include <sys/stat.h>
66 #include <sys/sx.h>
67 #include <sys/syscall.h>
68 #include <sys/sysctl.h>
69 #include <sys/sysent.h>
70 #include <sys/vnode.h>
71 #include <sys/syslog.h>
72 #include <sys/eventhandler.h>
73 #include <sys/user.h>
74 
75 #include <vm/vm.h>
76 #include <vm/vm_kern.h>
77 #include <vm/vm_param.h>
78 #include <vm/pmap.h>
79 #include <vm/vm_map.h>
80 #include <vm/vm_object.h>
81 #include <vm/vm_extern.h>
82 
83 #include <machine/elf.h>
84 #include <machine/md_var.h>
85 
86 #define ELF_NOTE_ROUNDSIZE	4
87 #define OLD_EI_BRAND	8
88 
89 static int __elfN(check_header)(const Elf_Ehdr *hdr);
90 static Elf_Brandinfo *__elfN(get_brandinfo)(struct image_params *imgp,
91     const char *interp, int32_t *osrel, uint32_t *fctl0);
92 static int __elfN(load_file)(struct proc *p, const char *file, u_long *addr,
93     u_long *entry);
94 static int __elfN(load_section)(struct image_params *imgp, vm_ooffset_t offset,
95     caddr_t vmaddr, size_t memsz, size_t filsz, vm_prot_t prot);
96 static int __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp);
97 static bool __elfN(freebsd_trans_osrel)(const Elf_Note *note,
98     int32_t *osrel);
99 static bool kfreebsd_trans_osrel(const Elf_Note *note, int32_t *osrel);
100 static boolean_t __elfN(check_note)(struct image_params *imgp,
101     Elf_Brandnote *checknote, int32_t *osrel, uint32_t *fctl0);
102 static vm_prot_t __elfN(trans_prot)(Elf_Word);
103 static Elf_Word __elfN(untrans_prot)(vm_prot_t);
104 
105 SYSCTL_NODE(_kern, OID_AUTO, __CONCAT(elf, __ELF_WORD_SIZE), CTLFLAG_RW, 0,
106     "");
107 
108 #define	CORE_BUF_SIZE	(16 * 1024)
109 
110 int __elfN(fallback_brand) = -1;
111 SYSCTL_INT(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO,
112     fallback_brand, CTLFLAG_RWTUN, &__elfN(fallback_brand), 0,
113     __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) " brand of last resort");
114 
115 static int elf_legacy_coredump = 0;
116 SYSCTL_INT(_debug, OID_AUTO, __elfN(legacy_coredump), CTLFLAG_RW,
117     &elf_legacy_coredump, 0,
118     "include all and only RW pages in core dumps");
119 
120 int __elfN(nxstack) =
121 #if defined(__amd64__) || defined(__powerpc64__) /* both 64 and 32 bit */ || \
122     (defined(__arm__) && __ARM_ARCH >= 7) || defined(__aarch64__) || \
123     defined(__riscv)
124 	1;
125 #else
126 	0;
127 #endif
128 SYSCTL_INT(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO,
129     nxstack, CTLFLAG_RW, &__elfN(nxstack), 0,
130     __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) ": enable non-executable stack");
131 
132 #if __ELF_WORD_SIZE == 32 && (defined(__amd64__) || defined(__i386__))
133 int i386_read_exec = 0;
134 SYSCTL_INT(_kern_elf32, OID_AUTO, read_exec, CTLFLAG_RW, &i386_read_exec, 0,
135     "enable execution from readable segments");
136 #endif
137 
138 SYSCTL_NODE(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO, aslr, CTLFLAG_RW, 0,
139     "");
140 #define	ASLR_NODE_OID	__CONCAT(__CONCAT(_kern_elf, __ELF_WORD_SIZE), _aslr)
141 
142 static int __elfN(aslr_enabled) = 0;
143 SYSCTL_INT(ASLR_NODE_OID, OID_AUTO, enable, CTLFLAG_RWTUN,
144     &__elfN(aslr_enabled), 0,
145     __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE))
146     ": enable address map randomization");
147 
148 static int __elfN(pie_aslr_enabled) = 0;
149 SYSCTL_INT(ASLR_NODE_OID, OID_AUTO, pie_enable, CTLFLAG_RWTUN,
150     &__elfN(pie_aslr_enabled), 0,
151     __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE))
152     ": enable address map randomization for PIE binaries");
153 
154 static int __elfN(aslr_honor_sbrk) = 1;
155 SYSCTL_INT(ASLR_NODE_OID, OID_AUTO, honor_sbrk, CTLFLAG_RW,
156     &__elfN(aslr_honor_sbrk), 0,
157     __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) ": assume sbrk is used");
158 
159 static Elf_Brandinfo *elf_brand_list[MAX_BRANDS];
160 
161 #define	aligned(a, t)	(rounddown2((u_long)(a), sizeof(t)) == (u_long)(a))
162 
163 static const char FREEBSD_ABI_VENDOR[] = "FreeBSD";
164 
165 Elf_Brandnote __elfN(freebsd_brandnote) = {
166 	.hdr.n_namesz	= sizeof(FREEBSD_ABI_VENDOR),
167 	.hdr.n_descsz	= sizeof(int32_t),
168 	.hdr.n_type	= NT_FREEBSD_ABI_TAG,
169 	.vendor		= FREEBSD_ABI_VENDOR,
170 	.flags		= BN_TRANSLATE_OSREL,
171 	.trans_osrel	= __elfN(freebsd_trans_osrel)
172 };
173 
174 static bool
175 __elfN(freebsd_trans_osrel)(const Elf_Note *note, int32_t *osrel)
176 {
177 	uintptr_t p;
178 
179 	p = (uintptr_t)(note + 1);
180 	p += roundup2(note->n_namesz, ELF_NOTE_ROUNDSIZE);
181 	*osrel = *(const int32_t *)(p);
182 
183 	return (true);
184 }
185 
186 static const char GNU_ABI_VENDOR[] = "GNU";
187 static int GNU_KFREEBSD_ABI_DESC = 3;
188 
189 Elf_Brandnote __elfN(kfreebsd_brandnote) = {
190 	.hdr.n_namesz	= sizeof(GNU_ABI_VENDOR),
191 	.hdr.n_descsz	= 16,	/* XXX at least 16 */
192 	.hdr.n_type	= 1,
193 	.vendor		= GNU_ABI_VENDOR,
194 	.flags		= BN_TRANSLATE_OSREL,
195 	.trans_osrel	= kfreebsd_trans_osrel
196 };
197 
198 static bool
199 kfreebsd_trans_osrel(const Elf_Note *note, int32_t *osrel)
200 {
201 	const Elf32_Word *desc;
202 	uintptr_t p;
203 
204 	p = (uintptr_t)(note + 1);
205 	p += roundup2(note->n_namesz, ELF_NOTE_ROUNDSIZE);
206 
207 	desc = (const Elf32_Word *)p;
208 	if (desc[0] != GNU_KFREEBSD_ABI_DESC)
209 		return (false);
210 
211 	/*
212 	 * Debian GNU/kFreeBSD embed the earliest compatible kernel version
213 	 * (__FreeBSD_version: <major><two digit minor>Rxx) in the LSB way.
214 	 */
215 	*osrel = desc[1] * 100000 + desc[2] * 1000 + desc[3];
216 
217 	return (true);
218 }
219 
220 int
221 __elfN(insert_brand_entry)(Elf_Brandinfo *entry)
222 {
223 	int i;
224 
225 	for (i = 0; i < MAX_BRANDS; i++) {
226 		if (elf_brand_list[i] == NULL) {
227 			elf_brand_list[i] = entry;
228 			break;
229 		}
230 	}
231 	if (i == MAX_BRANDS) {
232 		printf("WARNING: %s: could not insert brandinfo entry: %p\n",
233 			__func__, entry);
234 		return (-1);
235 	}
236 	return (0);
237 }
238 
239 int
240 __elfN(remove_brand_entry)(Elf_Brandinfo *entry)
241 {
242 	int i;
243 
244 	for (i = 0; i < MAX_BRANDS; i++) {
245 		if (elf_brand_list[i] == entry) {
246 			elf_brand_list[i] = NULL;
247 			break;
248 		}
249 	}
250 	if (i == MAX_BRANDS)
251 		return (-1);
252 	return (0);
253 }
254 
255 int
256 __elfN(brand_inuse)(Elf_Brandinfo *entry)
257 {
258 	struct proc *p;
259 	int rval = FALSE;
260 
261 	sx_slock(&allproc_lock);
262 	FOREACH_PROC_IN_SYSTEM(p) {
263 		if (p->p_sysent == entry->sysvec) {
264 			rval = TRUE;
265 			break;
266 		}
267 	}
268 	sx_sunlock(&allproc_lock);
269 
270 	return (rval);
271 }
272 
273 static Elf_Brandinfo *
274 __elfN(get_brandinfo)(struct image_params *imgp, const char *interp,
275     int32_t *osrel, uint32_t *fctl0)
276 {
277 	const Elf_Ehdr *hdr = (const Elf_Ehdr *)imgp->image_header;
278 	Elf_Brandinfo *bi, *bi_m;
279 	boolean_t ret;
280 	int i, interp_name_len;
281 
282 	interp_name_len = interp != NULL ? strlen(interp) + 1 : 0;
283 
284 	/*
285 	 * We support four types of branding -- (1) the ELF EI_OSABI field
286 	 * that SCO added to the ELF spec, (2) FreeBSD 3.x's traditional string
287 	 * branding w/in the ELF header, (3) path of the `interp_path'
288 	 * field, and (4) the ".note.ABI-tag" ELF section.
289 	 */
290 
291 	/* Look for an ".note.ABI-tag" ELF section */
292 	bi_m = NULL;
293 	for (i = 0; i < MAX_BRANDS; i++) {
294 		bi = elf_brand_list[i];
295 		if (bi == NULL)
296 			continue;
297 		if (interp != NULL && (bi->flags & BI_BRAND_ONLY_STATIC) != 0)
298 			continue;
299 		if (hdr->e_machine == bi->machine && (bi->flags &
300 		    (BI_BRAND_NOTE|BI_BRAND_NOTE_MANDATORY)) != 0) {
301 			ret = __elfN(check_note)(imgp, bi->brand_note, osrel,
302 			    fctl0);
303 			/* Give brand a chance to veto check_note's guess */
304 			if (ret && bi->header_supported)
305 				ret = bi->header_supported(imgp);
306 			/*
307 			 * If note checker claimed the binary, but the
308 			 * interpreter path in the image does not
309 			 * match default one for the brand, try to
310 			 * search for other brands with the same
311 			 * interpreter.  Either there is better brand
312 			 * with the right interpreter, or, failing
313 			 * this, we return first brand which accepted
314 			 * our note and, optionally, header.
315 			 */
316 			if (ret && bi_m == NULL && interp != NULL &&
317 			    (bi->interp_path == NULL ||
318 			    (strlen(bi->interp_path) + 1 != interp_name_len ||
319 			    strncmp(interp, bi->interp_path, interp_name_len)
320 			    != 0))) {
321 				bi_m = bi;
322 				ret = 0;
323 			}
324 			if (ret)
325 				return (bi);
326 		}
327 	}
328 	if (bi_m != NULL)
329 		return (bi_m);
330 
331 	/* If the executable has a brand, search for it in the brand list. */
332 	for (i = 0; i < MAX_BRANDS; i++) {
333 		bi = elf_brand_list[i];
334 		if (bi == NULL || (bi->flags & BI_BRAND_NOTE_MANDATORY) != 0 ||
335 		    (interp != NULL && (bi->flags & BI_BRAND_ONLY_STATIC) != 0))
336 			continue;
337 		if (hdr->e_machine == bi->machine &&
338 		    (hdr->e_ident[EI_OSABI] == bi->brand ||
339 		    (bi->compat_3_brand != NULL &&
340 		    strcmp((const char *)&hdr->e_ident[OLD_EI_BRAND],
341 		    bi->compat_3_brand) == 0))) {
342 			/* Looks good, but give brand a chance to veto */
343 			if (bi->header_supported == NULL ||
344 			    bi->header_supported(imgp)) {
345 				/*
346 				 * Again, prefer strictly matching
347 				 * interpreter path.
348 				 */
349 				if (interp_name_len == 0 &&
350 				    bi->interp_path == NULL)
351 					return (bi);
352 				if (bi->interp_path != NULL &&
353 				    strlen(bi->interp_path) + 1 ==
354 				    interp_name_len && strncmp(interp,
355 				    bi->interp_path, interp_name_len) == 0)
356 					return (bi);
357 				if (bi_m == NULL)
358 					bi_m = bi;
359 			}
360 		}
361 	}
362 	if (bi_m != NULL)
363 		return (bi_m);
364 
365 	/* No known brand, see if the header is recognized by any brand */
366 	for (i = 0; i < MAX_BRANDS; i++) {
367 		bi = elf_brand_list[i];
368 		if (bi == NULL || bi->flags & BI_BRAND_NOTE_MANDATORY ||
369 		    bi->header_supported == NULL)
370 			continue;
371 		if (hdr->e_machine == bi->machine) {
372 			ret = bi->header_supported(imgp);
373 			if (ret)
374 				return (bi);
375 		}
376 	}
377 
378 	/* Lacking a known brand, search for a recognized interpreter. */
379 	if (interp != NULL) {
380 		for (i = 0; i < MAX_BRANDS; i++) {
381 			bi = elf_brand_list[i];
382 			if (bi == NULL || (bi->flags &
383 			    (BI_BRAND_NOTE_MANDATORY | BI_BRAND_ONLY_STATIC))
384 			    != 0)
385 				continue;
386 			if (hdr->e_machine == bi->machine &&
387 			    bi->interp_path != NULL &&
388 			    /* ELF image p_filesz includes terminating zero */
389 			    strlen(bi->interp_path) + 1 == interp_name_len &&
390 			    strncmp(interp, bi->interp_path, interp_name_len)
391 			    == 0 && (bi->header_supported == NULL ||
392 			    bi->header_supported(imgp)))
393 				return (bi);
394 		}
395 	}
396 
397 	/* Lacking a recognized interpreter, try the default brand */
398 	for (i = 0; i < MAX_BRANDS; i++) {
399 		bi = elf_brand_list[i];
400 		if (bi == NULL || (bi->flags & BI_BRAND_NOTE_MANDATORY) != 0 ||
401 		    (interp != NULL && (bi->flags & BI_BRAND_ONLY_STATIC) != 0))
402 			continue;
403 		if (hdr->e_machine == bi->machine &&
404 		    __elfN(fallback_brand) == bi->brand &&
405 		    (bi->header_supported == NULL ||
406 		    bi->header_supported(imgp)))
407 			return (bi);
408 	}
409 	return (NULL);
410 }
411 
412 static int
413 __elfN(check_header)(const Elf_Ehdr *hdr)
414 {
415 	Elf_Brandinfo *bi;
416 	int i;
417 
418 	if (!IS_ELF(*hdr) ||
419 	    hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS ||
420 	    hdr->e_ident[EI_DATA] != ELF_TARG_DATA ||
421 	    hdr->e_ident[EI_VERSION] != EV_CURRENT ||
422 	    hdr->e_phentsize != sizeof(Elf_Phdr) ||
423 	    hdr->e_version != ELF_TARG_VER)
424 		return (ENOEXEC);
425 
426 	/*
427 	 * Make sure we have at least one brand for this machine.
428 	 */
429 
430 	for (i = 0; i < MAX_BRANDS; i++) {
431 		bi = elf_brand_list[i];
432 		if (bi != NULL && bi->machine == hdr->e_machine)
433 			break;
434 	}
435 	if (i == MAX_BRANDS)
436 		return (ENOEXEC);
437 
438 	return (0);
439 }
440 
441 static int
442 __elfN(map_partial)(vm_map_t map, vm_object_t object, vm_ooffset_t offset,
443     vm_offset_t start, vm_offset_t end, vm_prot_t prot)
444 {
445 	struct sf_buf *sf;
446 	int error;
447 	vm_offset_t off;
448 
449 	/*
450 	 * Create the page if it doesn't exist yet. Ignore errors.
451 	 */
452 	vm_map_fixed(map, NULL, 0, trunc_page(start), round_page(end) -
453 	    trunc_page(start), VM_PROT_ALL, VM_PROT_ALL, MAP_CHECK_EXCL);
454 
455 	/*
456 	 * Find the page from the underlying object.
457 	 */
458 	if (object != NULL) {
459 		sf = vm_imgact_map_page(object, offset);
460 		if (sf == NULL)
461 			return (KERN_FAILURE);
462 		off = offset - trunc_page(offset);
463 		error = copyout((caddr_t)sf_buf_kva(sf) + off, (caddr_t)start,
464 		    end - start);
465 		vm_imgact_unmap_page(sf);
466 		if (error != 0)
467 			return (KERN_FAILURE);
468 	}
469 
470 	return (KERN_SUCCESS);
471 }
472 
473 static int
474 __elfN(map_insert)(struct image_params *imgp, vm_map_t map, vm_object_t object,
475     vm_ooffset_t offset, vm_offset_t start, vm_offset_t end, vm_prot_t prot,
476     int cow)
477 {
478 	struct sf_buf *sf;
479 	vm_offset_t off;
480 	vm_size_t sz;
481 	int error, locked, rv;
482 
483 	if (start != trunc_page(start)) {
484 		rv = __elfN(map_partial)(map, object, offset, start,
485 		    round_page(start), prot);
486 		if (rv != KERN_SUCCESS)
487 			return (rv);
488 		offset += round_page(start) - start;
489 		start = round_page(start);
490 	}
491 	if (end != round_page(end)) {
492 		rv = __elfN(map_partial)(map, object, offset +
493 		    trunc_page(end) - start, trunc_page(end), end, prot);
494 		if (rv != KERN_SUCCESS)
495 			return (rv);
496 		end = trunc_page(end);
497 	}
498 	if (start >= end)
499 		return (KERN_SUCCESS);
500 	if ((offset & PAGE_MASK) != 0) {
501 		/*
502 		 * The mapping is not page aligned.  This means that we have
503 		 * to copy the data.
504 		 */
505 		rv = vm_map_fixed(map, NULL, 0, start, end - start,
506 		    prot | VM_PROT_WRITE, VM_PROT_ALL, MAP_CHECK_EXCL);
507 		if (rv != KERN_SUCCESS)
508 			return (rv);
509 		if (object == NULL)
510 			return (KERN_SUCCESS);
511 		for (; start < end; start += sz) {
512 			sf = vm_imgact_map_page(object, offset);
513 			if (sf == NULL)
514 				return (KERN_FAILURE);
515 			off = offset - trunc_page(offset);
516 			sz = end - start;
517 			if (sz > PAGE_SIZE - off)
518 				sz = PAGE_SIZE - off;
519 			error = copyout((caddr_t)sf_buf_kva(sf) + off,
520 			    (caddr_t)start, sz);
521 			vm_imgact_unmap_page(sf);
522 			if (error != 0)
523 				return (KERN_FAILURE);
524 			offset += sz;
525 		}
526 	} else {
527 		vm_object_reference(object);
528 		rv = vm_map_fixed(map, object, offset, start, end - start,
529 		    prot, VM_PROT_ALL, cow | MAP_CHECK_EXCL |
530 		    (object != NULL ? MAP_VN_EXEC : 0));
531 		if (rv != KERN_SUCCESS) {
532 			locked = VOP_ISLOCKED(imgp->vp);
533 			VOP_UNLOCK(imgp->vp, 0);
534 			vm_object_deallocate(object);
535 			vn_lock(imgp->vp, locked | LK_RETRY);
536 			return (rv);
537 		} else if (object != NULL) {
538 			MPASS(imgp->vp->v_object == object);
539 			VOP_SET_TEXT_CHECKED(imgp->vp);
540 		}
541 	}
542 	return (KERN_SUCCESS);
543 }
544 
545 static int
546 __elfN(load_section)(struct image_params *imgp, vm_ooffset_t offset,
547     caddr_t vmaddr, size_t memsz, size_t filsz, vm_prot_t prot)
548 {
549 	struct sf_buf *sf;
550 	size_t map_len;
551 	vm_map_t map;
552 	vm_object_t object;
553 	vm_offset_t off, map_addr;
554 	int error, rv, cow;
555 	size_t copy_len;
556 	vm_ooffset_t file_addr;
557 
558 	/*
559 	 * It's necessary to fail if the filsz + offset taken from the
560 	 * header is greater than the actual file pager object's size.
561 	 * If we were to allow this, then the vm_map_find() below would
562 	 * walk right off the end of the file object and into the ether.
563 	 *
564 	 * While I'm here, might as well check for something else that
565 	 * is invalid: filsz cannot be greater than memsz.
566 	 */
567 	if ((filsz != 0 && (off_t)filsz + offset > imgp->attr->va_size) ||
568 	    filsz > memsz) {
569 		uprintf("elf_load_section: truncated ELF file\n");
570 		return (ENOEXEC);
571 	}
572 
573 	object = imgp->object;
574 	map = &imgp->proc->p_vmspace->vm_map;
575 	map_addr = trunc_page((vm_offset_t)vmaddr);
576 	file_addr = trunc_page(offset);
577 
578 	/*
579 	 * We have two choices.  We can either clear the data in the last page
580 	 * of an oversized mapping, or we can start the anon mapping a page
581 	 * early and copy the initialized data into that first page.  We
582 	 * choose the second.
583 	 */
584 	if (filsz == 0)
585 		map_len = 0;
586 	else if (memsz > filsz)
587 		map_len = trunc_page(offset + filsz) - file_addr;
588 	else
589 		map_len = round_page(offset + filsz) - file_addr;
590 
591 	if (map_len != 0) {
592 		/* cow flags: don't dump readonly sections in core */
593 		cow = MAP_COPY_ON_WRITE | MAP_PREFAULT |
594 		    (prot & VM_PROT_WRITE ? 0 : MAP_DISABLE_COREDUMP);
595 
596 		rv = __elfN(map_insert)(imgp, map, object, file_addr,
597 		    map_addr, map_addr + map_len, prot, cow);
598 		if (rv != KERN_SUCCESS)
599 			return (EINVAL);
600 
601 		/* we can stop now if we've covered it all */
602 		if (memsz == filsz)
603 			return (0);
604 	}
605 
606 
607 	/*
608 	 * We have to get the remaining bit of the file into the first part
609 	 * of the oversized map segment.  This is normally because the .data
610 	 * segment in the file is extended to provide bss.  It's a neat idea
611 	 * to try and save a page, but it's a pain in the behind to implement.
612 	 */
613 	copy_len = filsz == 0 ? 0 : (offset + filsz) - trunc_page(offset +
614 	    filsz);
615 	map_addr = trunc_page((vm_offset_t)vmaddr + filsz);
616 	map_len = round_page((vm_offset_t)vmaddr + memsz) - map_addr;
617 
618 	/* This had damn well better be true! */
619 	if (map_len != 0) {
620 		rv = __elfN(map_insert)(imgp, map, NULL, 0, map_addr,
621 		    map_addr + map_len, prot, 0);
622 		if (rv != KERN_SUCCESS)
623 			return (EINVAL);
624 	}
625 
626 	if (copy_len != 0) {
627 		sf = vm_imgact_map_page(object, offset + filsz);
628 		if (sf == NULL)
629 			return (EIO);
630 
631 		/* send the page fragment to user space */
632 		off = trunc_page(offset + filsz) - trunc_page(offset + filsz);
633 		error = copyout((caddr_t)sf_buf_kva(sf) + off,
634 		    (caddr_t)map_addr, copy_len);
635 		vm_imgact_unmap_page(sf);
636 		if (error != 0)
637 			return (error);
638 	}
639 
640 	/*
641 	 * Remove write access to the page if it was only granted by map_insert
642 	 * to allow copyout.
643 	 */
644 	if ((prot & VM_PROT_WRITE) == 0)
645 		vm_map_protect(map, trunc_page(map_addr), round_page(map_addr +
646 		    map_len), prot, FALSE);
647 
648 	return (0);
649 }
650 
651 static int
652 __elfN(load_sections)(struct image_params *imgp, const Elf_Ehdr *hdr,
653     const Elf_Phdr *phdr, u_long rbase, u_long *base_addrp)
654 {
655 	vm_prot_t prot;
656 	u_long base_addr;
657 	bool first;
658 	int error, i;
659 
660 	ASSERT_VOP_LOCKED(imgp->vp, __func__);
661 
662 	base_addr = 0;
663 	first = true;
664 
665 	for (i = 0; i < hdr->e_phnum; i++) {
666 		if (phdr[i].p_type != PT_LOAD || phdr[i].p_memsz == 0)
667 			continue;
668 
669 		/* Loadable segment */
670 		prot = __elfN(trans_prot)(phdr[i].p_flags);
671 		error = __elfN(load_section)(imgp, phdr[i].p_offset,
672 		    (caddr_t)(uintptr_t)phdr[i].p_vaddr + rbase,
673 		    phdr[i].p_memsz, phdr[i].p_filesz, prot);
674 		if (error != 0)
675 			return (error);
676 
677 		/*
678 		 * Establish the base address if this is the first segment.
679 		 */
680 		if (first) {
681   			base_addr = trunc_page(phdr[i].p_vaddr + rbase);
682 			first = false;
683 		}
684 	}
685 
686 	if (base_addrp != NULL)
687 		*base_addrp = base_addr;
688 
689 	return (0);
690 }
691 
692 /*
693  * Load the file "file" into memory.  It may be either a shared object
694  * or an executable.
695  *
696  * The "addr" reference parameter is in/out.  On entry, it specifies
697  * the address where a shared object should be loaded.  If the file is
698  * an executable, this value is ignored.  On exit, "addr" specifies
699  * where the file was actually loaded.
700  *
701  * The "entry" reference parameter is out only.  On exit, it specifies
702  * the entry point for the loaded file.
703  */
704 static int
705 __elfN(load_file)(struct proc *p, const char *file, u_long *addr,
706 	u_long *entry)
707 {
708 	struct {
709 		struct nameidata nd;
710 		struct vattr attr;
711 		struct image_params image_params;
712 	} *tempdata;
713 	const Elf_Ehdr *hdr = NULL;
714 	const Elf_Phdr *phdr = NULL;
715 	struct nameidata *nd;
716 	struct vattr *attr;
717 	struct image_params *imgp;
718 	u_long rbase;
719 	u_long base_addr = 0;
720 	int error;
721 
722 #ifdef CAPABILITY_MODE
723 	/*
724 	 * XXXJA: This check can go away once we are sufficiently confident
725 	 * that the checks in namei() are correct.
726 	 */
727 	if (IN_CAPABILITY_MODE(curthread))
728 		return (ECAPMODE);
729 #endif
730 
731 	tempdata = malloc(sizeof(*tempdata), M_TEMP, M_WAITOK);
732 	nd = &tempdata->nd;
733 	attr = &tempdata->attr;
734 	imgp = &tempdata->image_params;
735 
736 	/*
737 	 * Initialize part of the common data
738 	 */
739 	imgp->proc = p;
740 	imgp->attr = attr;
741 	imgp->firstpage = NULL;
742 	imgp->image_header = NULL;
743 	imgp->object = NULL;
744 	imgp->execlabel = NULL;
745 
746 	NDINIT(nd, LOOKUP, FOLLOW | LOCKSHARED | LOCKLEAF, UIO_SYSSPACE, file,
747 	    curthread);
748 	if ((error = namei(nd)) != 0) {
749 		nd->ni_vp = NULL;
750 		goto fail;
751 	}
752 	NDFREE(nd, NDF_ONLY_PNBUF);
753 	imgp->vp = nd->ni_vp;
754 
755 	/*
756 	 * Check permissions, modes, uid, etc on the file, and "open" it.
757 	 */
758 	error = exec_check_permissions(imgp);
759 	if (error)
760 		goto fail;
761 
762 	error = exec_map_first_page(imgp);
763 	if (error)
764 		goto fail;
765 
766 	imgp->object = nd->ni_vp->v_object;
767 
768 	hdr = (const Elf_Ehdr *)imgp->image_header;
769 	if ((error = __elfN(check_header)(hdr)) != 0)
770 		goto fail;
771 	if (hdr->e_type == ET_DYN)
772 		rbase = *addr;
773 	else if (hdr->e_type == ET_EXEC)
774 		rbase = 0;
775 	else {
776 		error = ENOEXEC;
777 		goto fail;
778 	}
779 
780 	/* Only support headers that fit within first page for now      */
781 	if ((hdr->e_phoff > PAGE_SIZE) ||
782 	    (u_int)hdr->e_phentsize * hdr->e_phnum > PAGE_SIZE - hdr->e_phoff) {
783 		error = ENOEXEC;
784 		goto fail;
785 	}
786 
787 	phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff);
788 	if (!aligned(phdr, Elf_Addr)) {
789 		error = ENOEXEC;
790 		goto fail;
791 	}
792 
793 	error = __elfN(load_sections)(imgp, hdr, phdr, rbase, &base_addr);
794 	if (error != 0)
795 		goto fail;
796 
797 	*addr = base_addr;
798 	*entry = (unsigned long)hdr->e_entry + rbase;
799 
800 fail:
801 	if (imgp->firstpage)
802 		exec_unmap_first_page(imgp);
803 
804 	if (nd->ni_vp) {
805 		if (imgp->textset)
806 			VOP_UNSET_TEXT_CHECKED(nd->ni_vp);
807 		vput(nd->ni_vp);
808 	}
809 	free(tempdata, M_TEMP);
810 
811 	return (error);
812 }
813 
814 static u_long
815 __CONCAT(rnd_, __elfN(base))(vm_map_t map __unused, u_long minv, u_long maxv,
816     u_int align)
817 {
818 	u_long rbase, res;
819 
820 	MPASS(vm_map_min(map) <= minv);
821 	MPASS(maxv <= vm_map_max(map));
822 	MPASS(minv < maxv);
823 	MPASS(minv + align < maxv);
824 	arc4rand(&rbase, sizeof(rbase), 0);
825 	res = roundup(minv, (u_long)align) + rbase % (maxv - minv);
826 	res &= ~((u_long)align - 1);
827 	if (res >= maxv)
828 		res -= align;
829 	KASSERT(res >= minv,
830 	    ("res %#lx < minv %#lx, maxv %#lx rbase %#lx",
831 	    res, minv, maxv, rbase));
832 	KASSERT(res < maxv,
833 	    ("res %#lx > maxv %#lx, minv %#lx rbase %#lx",
834 	    res, maxv, minv, rbase));
835 	return (res);
836 }
837 
838 static int
839 __elfN(enforce_limits)(struct image_params *imgp, const Elf_Ehdr *hdr,
840     const Elf_Phdr *phdr, u_long et_dyn_addr)
841 {
842 	struct vmspace *vmspace;
843 	const char *err_str;
844 	u_long text_size, data_size, total_size, text_addr, data_addr;
845 	u_long seg_size, seg_addr;
846 	int i;
847 
848 	err_str = NULL;
849 	text_size = data_size = total_size = text_addr = data_addr = 0;
850 
851 	for (i = 0; i < hdr->e_phnum; i++) {
852 		if (phdr[i].p_type != PT_LOAD || phdr[i].p_memsz == 0)
853 			continue;
854 
855 		seg_addr = trunc_page(phdr[i].p_vaddr + et_dyn_addr);
856 		seg_size = round_page(phdr[i].p_memsz +
857 		    phdr[i].p_vaddr + et_dyn_addr - seg_addr);
858 
859 		/*
860 		 * Make the largest executable segment the official
861 		 * text segment and all others data.
862 		 *
863 		 * Note that obreak() assumes that data_addr + data_size == end
864 		 * of data load area, and the ELF file format expects segments
865 		 * to be sorted by address.  If multiple data segments exist,
866 		 * the last one will be used.
867 		 */
868 
869 		if ((phdr[i].p_flags & PF_X) != 0 && text_size < seg_size) {
870 			text_size = seg_size;
871 			text_addr = seg_addr;
872 		} else {
873 			data_size = seg_size;
874 			data_addr = seg_addr;
875 		}
876 		total_size += seg_size;
877 	}
878 
879 	if (data_addr == 0 && data_size == 0) {
880 		data_addr = text_addr;
881 		data_size = text_size;
882 	}
883 
884 	/*
885 	 * Check limits.  It should be safe to check the
886 	 * limits after loading the segments since we do
887 	 * not actually fault in all the segments pages.
888 	 */
889 	PROC_LOCK(imgp->proc);
890 	if (data_size > lim_cur_proc(imgp->proc, RLIMIT_DATA))
891 		err_str = "Data segment size exceeds process limit";
892 	else if (text_size > maxtsiz)
893 		err_str = "Text segment size exceeds system limit";
894 	else if (total_size > lim_cur_proc(imgp->proc, RLIMIT_VMEM))
895 		err_str = "Total segment size exceeds process limit";
896 	else if (racct_set(imgp->proc, RACCT_DATA, data_size) != 0)
897 		err_str = "Data segment size exceeds resource limit";
898 	else if (racct_set(imgp->proc, RACCT_VMEM, total_size) != 0)
899 		err_str = "Total segment size exceeds resource limit";
900 	PROC_UNLOCK(imgp->proc);
901 	if (err_str != NULL) {
902 		uprintf("%s\n", err_str);
903 		return (ENOMEM);
904 	}
905 
906 	vmspace = imgp->proc->p_vmspace;
907 	vmspace->vm_tsize = text_size >> PAGE_SHIFT;
908 	vmspace->vm_taddr = (caddr_t)(uintptr_t)text_addr;
909 	vmspace->vm_dsize = data_size >> PAGE_SHIFT;
910 	vmspace->vm_daddr = (caddr_t)(uintptr_t)data_addr;
911 
912 	return (0);
913 }
914 
915 static int
916 __elfN(get_interp)(struct image_params *imgp, const Elf_Phdr *phdr,
917     char **interpp, bool *free_interpp)
918 {
919 	struct thread *td;
920 	char *interp;
921 	int error, interp_name_len;
922 
923 	KASSERT(phdr->p_type == PT_INTERP,
924 	    ("%s: p_type %u != PT_INTERP", __func__, phdr->p_type));
925 	ASSERT_VOP_LOCKED(imgp->vp, __func__);
926 
927 	td = curthread;
928 
929 	/* Path to interpreter */
930 	if (phdr->p_filesz < 2 || phdr->p_filesz > MAXPATHLEN) {
931 		uprintf("Invalid PT_INTERP\n");
932 		return (ENOEXEC);
933 	}
934 
935 	interp_name_len = phdr->p_filesz;
936 	if (phdr->p_offset > PAGE_SIZE ||
937 	    interp_name_len > PAGE_SIZE - phdr->p_offset) {
938 		/*
939 		 * The vnode lock might be needed by the pagedaemon to
940 		 * clean pages owned by the vnode.  Do not allow sleep
941 		 * waiting for memory with the vnode locked, instead
942 		 * try non-sleepable allocation first, and if it
943 		 * fails, go to the slow path were we drop the lock
944 		 * and do M_WAITOK.  A text reference prevents
945 		 * modifications to the vnode content.
946 		 */
947 		interp = malloc(interp_name_len + 1, M_TEMP, M_NOWAIT);
948 		if (interp == NULL) {
949 			VOP_UNLOCK(imgp->vp, 0);
950 			interp = malloc(interp_name_len + 1, M_TEMP, M_WAITOK);
951 			vn_lock(imgp->vp, LK_SHARED | LK_RETRY);
952 		}
953 
954 		error = vn_rdwr(UIO_READ, imgp->vp, interp,
955 		    interp_name_len, phdr->p_offset,
956 		    UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred,
957 		    NOCRED, NULL, td);
958 		if (error != 0) {
959 			free(interp, M_TEMP);
960 			uprintf("i/o error PT_INTERP %d\n", error);
961 			return (error);
962 		}
963 		interp[interp_name_len] = '\0';
964 
965 		*interpp = interp;
966 		*free_interpp = true;
967 		return (0);
968 	}
969 
970 	interp = __DECONST(char *, imgp->image_header) + phdr->p_offset;
971 	if (interp[interp_name_len - 1] != '\0') {
972 		uprintf("Invalid PT_INTERP\n");
973 		return (ENOEXEC);
974 	}
975 
976 	*interpp = interp;
977 	*free_interpp = false;
978 	return (0);
979 }
980 
981 static int
982 __elfN(load_interp)(struct image_params *imgp, const Elf_Brandinfo *brand_info,
983     const char *interp, u_long *addr, u_long *entry)
984 {
985 	char *path;
986 	int error;
987 
988 	if (brand_info->emul_path != NULL &&
989 	    brand_info->emul_path[0] != '\0') {
990 		path = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
991 		snprintf(path, MAXPATHLEN, "%s%s",
992 		    brand_info->emul_path, interp);
993 		error = __elfN(load_file)(imgp->proc, path, addr, entry);
994 		free(path, M_TEMP);
995 		if (error == 0)
996 			return (0);
997 	}
998 
999 	if (brand_info->interp_newpath != NULL &&
1000 	    (brand_info->interp_path == NULL ||
1001 	    strcmp(interp, brand_info->interp_path) == 0)) {
1002 		error = __elfN(load_file)(imgp->proc,
1003 		    brand_info->interp_newpath, addr, entry);
1004 		if (error == 0)
1005 			return (0);
1006 	}
1007 
1008 	error = __elfN(load_file)(imgp->proc, interp, addr, entry);
1009 	if (error == 0)
1010 		return (0);
1011 
1012 	uprintf("ELF interpreter %s not found, error %d\n", interp, error);
1013 	return (error);
1014 }
1015 
1016 /*
1017  * Impossible et_dyn_addr initial value indicating that the real base
1018  * must be calculated later with some randomization applied.
1019  */
1020 #define	ET_DYN_ADDR_RAND	1
1021 
1022 static int
1023 __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp)
1024 {
1025 	struct thread *td;
1026 	const Elf_Ehdr *hdr;
1027 	const Elf_Phdr *phdr;
1028 	Elf_Auxargs *elf_auxargs;
1029 	struct vmspace *vmspace;
1030 	vm_map_t map;
1031 	char *interp;
1032 	Elf_Brandinfo *brand_info;
1033 	struct sysentvec *sv;
1034 	u_long addr, baddr, et_dyn_addr, entry, proghdr;
1035 	u_long maxalign, mapsz, maxv, maxv1;
1036 	uint32_t fctl0;
1037 	int32_t osrel;
1038 	bool free_interp;
1039 	int error, i, n;
1040 
1041 	hdr = (const Elf_Ehdr *)imgp->image_header;
1042 
1043 	/*
1044 	 * Do we have a valid ELF header ?
1045 	 *
1046 	 * Only allow ET_EXEC & ET_DYN here, reject ET_DYN later
1047 	 * if particular brand doesn't support it.
1048 	 */
1049 	if (__elfN(check_header)(hdr) != 0 ||
1050 	    (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN))
1051 		return (-1);
1052 
1053 	/*
1054 	 * From here on down, we return an errno, not -1, as we've
1055 	 * detected an ELF file.
1056 	 */
1057 
1058 	if ((hdr->e_phoff > PAGE_SIZE) ||
1059 	    (u_int)hdr->e_phentsize * hdr->e_phnum > PAGE_SIZE - hdr->e_phoff) {
1060 		/* Only support headers in first page for now */
1061 		uprintf("Program headers not in the first page\n");
1062 		return (ENOEXEC);
1063 	}
1064 	phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff);
1065 	if (!aligned(phdr, Elf_Addr)) {
1066 		uprintf("Unaligned program headers\n");
1067 		return (ENOEXEC);
1068 	}
1069 
1070 	n = error = 0;
1071 	baddr = 0;
1072 	osrel = 0;
1073 	fctl0 = 0;
1074 	entry = proghdr = 0;
1075 	interp = NULL;
1076 	free_interp = false;
1077 	td = curthread;
1078 	maxalign = PAGE_SIZE;
1079 	mapsz = 0;
1080 
1081 	for (i = 0; i < hdr->e_phnum; i++) {
1082 		switch (phdr[i].p_type) {
1083 		case PT_LOAD:
1084 			if (n == 0)
1085 				baddr = phdr[i].p_vaddr;
1086 			if (phdr[i].p_align > maxalign)
1087 				maxalign = phdr[i].p_align;
1088 			mapsz += phdr[i].p_memsz;
1089 			n++;
1090 
1091 			/*
1092 			 * If this segment contains the program headers,
1093 			 * remember their virtual address for the AT_PHDR
1094 			 * aux entry. Static binaries don't usually include
1095 			 * a PT_PHDR entry.
1096 			 */
1097 			if (phdr[i].p_offset == 0 &&
1098 			    hdr->e_phoff + hdr->e_phnum * hdr->e_phentsize
1099 				<= phdr[i].p_filesz)
1100 				proghdr = phdr[i].p_vaddr + hdr->e_phoff;
1101 			break;
1102 		case PT_INTERP:
1103 			/* Path to interpreter */
1104 			if (interp != NULL) {
1105 				uprintf("Multiple PT_INTERP headers\n");
1106 				error = ENOEXEC;
1107 				goto ret;
1108 			}
1109 			error = __elfN(get_interp)(imgp, &phdr[i], &interp,
1110 			    &free_interp);
1111 			if (error != 0)
1112 				goto ret;
1113 			break;
1114 		case PT_GNU_STACK:
1115 			if (__elfN(nxstack))
1116 				imgp->stack_prot =
1117 				    __elfN(trans_prot)(phdr[i].p_flags);
1118 			imgp->stack_sz = phdr[i].p_memsz;
1119 			break;
1120 		case PT_PHDR: 	/* Program header table info */
1121 			proghdr = phdr[i].p_vaddr;
1122 			break;
1123 		}
1124 	}
1125 
1126 	brand_info = __elfN(get_brandinfo)(imgp, interp, &osrel, &fctl0);
1127 	if (brand_info == NULL) {
1128 		uprintf("ELF binary type \"%u\" not known.\n",
1129 		    hdr->e_ident[EI_OSABI]);
1130 		error = ENOEXEC;
1131 		goto ret;
1132 	}
1133 	sv = brand_info->sysvec;
1134 	et_dyn_addr = 0;
1135 	if (hdr->e_type == ET_DYN) {
1136 		if ((brand_info->flags & BI_CAN_EXEC_DYN) == 0) {
1137 			uprintf("Cannot execute shared object\n");
1138 			error = ENOEXEC;
1139 			goto ret;
1140 		}
1141 		/*
1142 		 * Honour the base load address from the dso if it is
1143 		 * non-zero for some reason.
1144 		 */
1145 		if (baddr == 0) {
1146 			if ((sv->sv_flags & SV_ASLR) == 0 ||
1147 			    (fctl0 & NT_FREEBSD_FCTL_ASLR_DISABLE) != 0)
1148 				et_dyn_addr = ET_DYN_LOAD_ADDR;
1149 			else if ((__elfN(pie_aslr_enabled) &&
1150 			    (imgp->proc->p_flag2 & P2_ASLR_DISABLE) == 0) ||
1151 			    (imgp->proc->p_flag2 & P2_ASLR_ENABLE) != 0)
1152 				et_dyn_addr = ET_DYN_ADDR_RAND;
1153 			else
1154 				et_dyn_addr = ET_DYN_LOAD_ADDR;
1155 		}
1156 	}
1157 
1158 	/*
1159 	 * Avoid a possible deadlock if the current address space is destroyed
1160 	 * and that address space maps the locked vnode.  In the common case,
1161 	 * the locked vnode's v_usecount is decremented but remains greater
1162 	 * than zero.  Consequently, the vnode lock is not needed by vrele().
1163 	 * However, in cases where the vnode lock is external, such as nullfs,
1164 	 * v_usecount may become zero.
1165 	 *
1166 	 * The VV_TEXT flag prevents modifications to the executable while
1167 	 * the vnode is unlocked.
1168 	 */
1169 	VOP_UNLOCK(imgp->vp, 0);
1170 
1171 	/*
1172 	 * Decide whether to enable randomization of user mappings.
1173 	 * First, reset user preferences for the setid binaries.
1174 	 * Then, account for the support of the randomization by the
1175 	 * ABI, by user preferences, and make special treatment for
1176 	 * PIE binaries.
1177 	 */
1178 	if (imgp->credential_setid) {
1179 		PROC_LOCK(imgp->proc);
1180 		imgp->proc->p_flag2 &= ~(P2_ASLR_ENABLE | P2_ASLR_DISABLE);
1181 		PROC_UNLOCK(imgp->proc);
1182 	}
1183 	if ((sv->sv_flags & SV_ASLR) == 0 ||
1184 	    (imgp->proc->p_flag2 & P2_ASLR_DISABLE) != 0 ||
1185 	    (fctl0 & NT_FREEBSD_FCTL_ASLR_DISABLE) != 0) {
1186 		KASSERT(et_dyn_addr != ET_DYN_ADDR_RAND,
1187 		    ("et_dyn_addr == RAND and !ASLR"));
1188 	} else if ((imgp->proc->p_flag2 & P2_ASLR_ENABLE) != 0 ||
1189 	    (__elfN(aslr_enabled) && hdr->e_type == ET_EXEC) ||
1190 	    et_dyn_addr == ET_DYN_ADDR_RAND) {
1191 		imgp->map_flags |= MAP_ASLR;
1192 		/*
1193 		 * If user does not care about sbrk, utilize the bss
1194 		 * grow region for mappings as well.  We can select
1195 		 * the base for the image anywere and still not suffer
1196 		 * from the fragmentation.
1197 		 */
1198 		if (!__elfN(aslr_honor_sbrk) ||
1199 		    (imgp->proc->p_flag2 & P2_ASLR_IGNSTART) != 0)
1200 			imgp->map_flags |= MAP_ASLR_IGNSTART;
1201 	}
1202 
1203 	error = exec_new_vmspace(imgp, sv);
1204 	vmspace = imgp->proc->p_vmspace;
1205 	map = &vmspace->vm_map;
1206 
1207 	imgp->proc->p_sysent = sv;
1208 
1209 	maxv = vm_map_max(map) - lim_max(td, RLIMIT_STACK);
1210 	if (et_dyn_addr == ET_DYN_ADDR_RAND) {
1211 		KASSERT((map->flags & MAP_ASLR) != 0,
1212 		    ("ET_DYN_ADDR_RAND but !MAP_ASLR"));
1213 		et_dyn_addr = __CONCAT(rnd_, __elfN(base))(map,
1214 		    vm_map_min(map) + mapsz + lim_max(td, RLIMIT_DATA),
1215 		    /* reserve half of the address space to interpreter */
1216 		    maxv / 2, 1UL << flsl(maxalign));
1217 	}
1218 
1219 	vn_lock(imgp->vp, LK_SHARED | LK_RETRY);
1220 	if (error != 0)
1221 		goto ret;
1222 
1223 	error = __elfN(load_sections)(imgp, hdr, phdr, et_dyn_addr, NULL);
1224 	if (error != 0)
1225 		goto ret;
1226 
1227 	error = __elfN(enforce_limits)(imgp, hdr, phdr, et_dyn_addr);
1228 	if (error != 0)
1229 		goto ret;
1230 
1231 	entry = (u_long)hdr->e_entry + et_dyn_addr;
1232 
1233 	/*
1234 	 * We load the dynamic linker where a userland call
1235 	 * to mmap(0, ...) would put it.  The rationale behind this
1236 	 * calculation is that it leaves room for the heap to grow to
1237 	 * its maximum allowed size.
1238 	 */
1239 	addr = round_page((vm_offset_t)vmspace->vm_daddr + lim_max(td,
1240 	    RLIMIT_DATA));
1241 	if ((map->flags & MAP_ASLR) != 0) {
1242 		maxv1 = maxv / 2 + addr / 2;
1243 		MPASS(maxv1 >= addr);	/* No overflow */
1244 		map->anon_loc = __CONCAT(rnd_, __elfN(base))(map, addr, maxv1,
1245 		    MAXPAGESIZES > 1 ? pagesizes[1] : pagesizes[0]);
1246 	} else {
1247 		map->anon_loc = addr;
1248 	}
1249 
1250 	imgp->entry_addr = entry;
1251 
1252 	if (interp != NULL) {
1253 		VOP_UNLOCK(imgp->vp, 0);
1254 		if ((map->flags & MAP_ASLR) != 0) {
1255 			/* Assume that interpeter fits into 1/4 of AS */
1256 			maxv1 = maxv / 2 + addr / 2;
1257 			MPASS(maxv1 >= addr);	/* No overflow */
1258 			addr = __CONCAT(rnd_, __elfN(base))(map, addr,
1259 			    maxv1, PAGE_SIZE);
1260 		}
1261 		error = __elfN(load_interp)(imgp, brand_info, interp, &addr,
1262 		    &imgp->entry_addr);
1263 		vn_lock(imgp->vp, LK_SHARED | LK_RETRY);
1264 		if (error != 0)
1265 			goto ret;
1266 	} else
1267 		addr = et_dyn_addr;
1268 
1269 	/*
1270 	 * Construct auxargs table (used by the fixup routine)
1271 	 */
1272 	elf_auxargs = malloc(sizeof(Elf_Auxargs), M_TEMP, M_NOWAIT);
1273 	if (elf_auxargs == NULL) {
1274 		VOP_UNLOCK(imgp->vp, 0);
1275 		elf_auxargs = malloc(sizeof(Elf_Auxargs), M_TEMP, M_WAITOK);
1276 		vn_lock(imgp->vp, LK_SHARED | LK_RETRY);
1277 	}
1278 	elf_auxargs->execfd = -1;
1279 	elf_auxargs->phdr = proghdr + et_dyn_addr;
1280 	elf_auxargs->phent = hdr->e_phentsize;
1281 	elf_auxargs->phnum = hdr->e_phnum;
1282 	elf_auxargs->pagesz = PAGE_SIZE;
1283 	elf_auxargs->base = addr;
1284 	elf_auxargs->flags = 0;
1285 	elf_auxargs->entry = entry;
1286 	elf_auxargs->hdr_eflags = hdr->e_flags;
1287 
1288 	imgp->auxargs = elf_auxargs;
1289 	imgp->interpreted = 0;
1290 	imgp->reloc_base = addr;
1291 	imgp->proc->p_osrel = osrel;
1292 	imgp->proc->p_fctl0 = fctl0;
1293 	imgp->proc->p_elf_machine = hdr->e_machine;
1294 	imgp->proc->p_elf_flags = hdr->e_flags;
1295 
1296 ret:
1297 	if (free_interp)
1298 		free(interp, M_TEMP);
1299 	return (error);
1300 }
1301 
1302 #define	suword __CONCAT(suword, __ELF_WORD_SIZE)
1303 
1304 int
1305 __elfN(freebsd_fixup)(register_t **stack_base, struct image_params *imgp)
1306 {
1307 	Elf_Auxargs *args = (Elf_Auxargs *)imgp->auxargs;
1308 	Elf_Auxinfo *argarray, *pos;
1309 	Elf_Addr *base, *auxbase;
1310 	int error;
1311 
1312 	base = (Elf_Addr *)*stack_base;
1313 	auxbase = base + imgp->args->argc + 1 + imgp->args->envc + 1;
1314 	argarray = pos = malloc(AT_COUNT * sizeof(*pos), M_TEMP,
1315 	    M_WAITOK | M_ZERO);
1316 
1317 	if (args->execfd != -1)
1318 		AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd);
1319 	AUXARGS_ENTRY(pos, AT_PHDR, args->phdr);
1320 	AUXARGS_ENTRY(pos, AT_PHENT, args->phent);
1321 	AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum);
1322 	AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz);
1323 	AUXARGS_ENTRY(pos, AT_FLAGS, args->flags);
1324 	AUXARGS_ENTRY(pos, AT_ENTRY, args->entry);
1325 	AUXARGS_ENTRY(pos, AT_BASE, args->base);
1326 	AUXARGS_ENTRY(pos, AT_EHDRFLAGS, args->hdr_eflags);
1327 	if (imgp->execpathp != 0)
1328 		AUXARGS_ENTRY(pos, AT_EXECPATH, imgp->execpathp);
1329 	AUXARGS_ENTRY(pos, AT_OSRELDATE,
1330 	    imgp->proc->p_ucred->cr_prison->pr_osreldate);
1331 	if (imgp->canary != 0) {
1332 		AUXARGS_ENTRY(pos, AT_CANARY, imgp->canary);
1333 		AUXARGS_ENTRY(pos, AT_CANARYLEN, imgp->canarylen);
1334 	}
1335 	AUXARGS_ENTRY(pos, AT_NCPUS, mp_ncpus);
1336 	if (imgp->pagesizes != 0) {
1337 		AUXARGS_ENTRY(pos, AT_PAGESIZES, imgp->pagesizes);
1338 		AUXARGS_ENTRY(pos, AT_PAGESIZESLEN, imgp->pagesizeslen);
1339 	}
1340 	if (imgp->sysent->sv_timekeep_base != 0) {
1341 		AUXARGS_ENTRY(pos, AT_TIMEKEEP,
1342 		    imgp->sysent->sv_timekeep_base);
1343 	}
1344 	AUXARGS_ENTRY(pos, AT_STACKPROT, imgp->sysent->sv_shared_page_obj
1345 	    != NULL && imgp->stack_prot != 0 ? imgp->stack_prot :
1346 	    imgp->sysent->sv_stackprot);
1347 	if (imgp->sysent->sv_hwcap != NULL)
1348 		AUXARGS_ENTRY(pos, AT_HWCAP, *imgp->sysent->sv_hwcap);
1349 	if (imgp->sysent->sv_hwcap2 != NULL)
1350 		AUXARGS_ENTRY(pos, AT_HWCAP2, *imgp->sysent->sv_hwcap2);
1351 	AUXARGS_ENTRY(pos, AT_NULL, 0);
1352 
1353 	free(imgp->auxargs, M_TEMP);
1354 	imgp->auxargs = NULL;
1355 	KASSERT(pos - argarray <= AT_COUNT, ("Too many auxargs"));
1356 
1357 	error = copyout(argarray, auxbase, sizeof(*argarray) * AT_COUNT);
1358 	free(argarray, M_TEMP);
1359 	if (error != 0)
1360 		return (error);
1361 
1362 	base--;
1363 	if (suword(base, imgp->args->argc) == -1)
1364 		return (EFAULT);
1365 	*stack_base = (register_t *)base;
1366 	return (0);
1367 }
1368 
1369 /*
1370  * Code for generating ELF core dumps.
1371  */
1372 
1373 typedef void (*segment_callback)(vm_map_entry_t, void *);
1374 
1375 /* Closure for cb_put_phdr(). */
1376 struct phdr_closure {
1377 	Elf_Phdr *phdr;		/* Program header to fill in */
1378 	Elf_Off offset;		/* Offset of segment in core file */
1379 };
1380 
1381 /* Closure for cb_size_segment(). */
1382 struct sseg_closure {
1383 	int count;		/* Count of writable segments. */
1384 	size_t size;		/* Total size of all writable segments. */
1385 };
1386 
1387 typedef void (*outfunc_t)(void *, struct sbuf *, size_t *);
1388 
1389 struct note_info {
1390 	int		type;		/* Note type. */
1391 	outfunc_t 	outfunc; 	/* Output function. */
1392 	void		*outarg;	/* Argument for the output function. */
1393 	size_t		outsize;	/* Output size. */
1394 	TAILQ_ENTRY(note_info) link;	/* Link to the next note info. */
1395 };
1396 
1397 TAILQ_HEAD(note_info_list, note_info);
1398 
1399 /* Coredump output parameters. */
1400 struct coredump_params {
1401 	off_t		offset;
1402 	struct ucred	*active_cred;
1403 	struct ucred	*file_cred;
1404 	struct thread	*td;
1405 	struct vnode	*vp;
1406 	struct compressor *comp;
1407 };
1408 
1409 extern int compress_user_cores;
1410 extern int compress_user_cores_level;
1411 
1412 static void cb_put_phdr(vm_map_entry_t, void *);
1413 static void cb_size_segment(vm_map_entry_t, void *);
1414 static int core_write(struct coredump_params *, const void *, size_t, off_t,
1415     enum uio_seg);
1416 static void each_dumpable_segment(struct thread *, segment_callback, void *);
1417 static int __elfN(corehdr)(struct coredump_params *, int, void *, size_t,
1418     struct note_info_list *, size_t);
1419 static void __elfN(prepare_notes)(struct thread *, struct note_info_list *,
1420     size_t *);
1421 static void __elfN(puthdr)(struct thread *, void *, size_t, int, size_t);
1422 static void __elfN(putnote)(struct note_info *, struct sbuf *);
1423 static size_t register_note(struct note_info_list *, int, outfunc_t, void *);
1424 static int sbuf_drain_core_output(void *, const char *, int);
1425 static int sbuf_drain_count(void *arg, const char *data, int len);
1426 
1427 static void __elfN(note_fpregset)(void *, struct sbuf *, size_t *);
1428 static void __elfN(note_prpsinfo)(void *, struct sbuf *, size_t *);
1429 static void __elfN(note_prstatus)(void *, struct sbuf *, size_t *);
1430 static void __elfN(note_threadmd)(void *, struct sbuf *, size_t *);
1431 static void __elfN(note_thrmisc)(void *, struct sbuf *, size_t *);
1432 static void __elfN(note_ptlwpinfo)(void *, struct sbuf *, size_t *);
1433 static void __elfN(note_procstat_auxv)(void *, struct sbuf *, size_t *);
1434 static void __elfN(note_procstat_proc)(void *, struct sbuf *, size_t *);
1435 static void __elfN(note_procstat_psstrings)(void *, struct sbuf *, size_t *);
1436 static void note_procstat_files(void *, struct sbuf *, size_t *);
1437 static void note_procstat_groups(void *, struct sbuf *, size_t *);
1438 static void note_procstat_osrel(void *, struct sbuf *, size_t *);
1439 static void note_procstat_rlimit(void *, struct sbuf *, size_t *);
1440 static void note_procstat_umask(void *, struct sbuf *, size_t *);
1441 static void note_procstat_vmmap(void *, struct sbuf *, size_t *);
1442 
1443 /*
1444  * Write out a core segment to the compression stream.
1445  */
1446 static int
1447 compress_chunk(struct coredump_params *p, char *base, char *buf, u_int len)
1448 {
1449 	u_int chunk_len;
1450 	int error;
1451 
1452 	while (len > 0) {
1453 		chunk_len = MIN(len, CORE_BUF_SIZE);
1454 
1455 		/*
1456 		 * We can get EFAULT error here.
1457 		 * In that case zero out the current chunk of the segment.
1458 		 */
1459 		error = copyin(base, buf, chunk_len);
1460 		if (error != 0)
1461 			bzero(buf, chunk_len);
1462 		error = compressor_write(p->comp, buf, chunk_len);
1463 		if (error != 0)
1464 			break;
1465 		base += chunk_len;
1466 		len -= chunk_len;
1467 	}
1468 	return (error);
1469 }
1470 
1471 static int
1472 core_compressed_write(void *base, size_t len, off_t offset, void *arg)
1473 {
1474 
1475 	return (core_write((struct coredump_params *)arg, base, len, offset,
1476 	    UIO_SYSSPACE));
1477 }
1478 
1479 static int
1480 core_write(struct coredump_params *p, const void *base, size_t len,
1481     off_t offset, enum uio_seg seg)
1482 {
1483 
1484 	return (vn_rdwr_inchunks(UIO_WRITE, p->vp, __DECONST(void *, base),
1485 	    len, offset, seg, IO_UNIT | IO_DIRECT | IO_RANGELOCKED,
1486 	    p->active_cred, p->file_cred, NULL, p->td));
1487 }
1488 
1489 static int
1490 core_output(void *base, size_t len, off_t offset, struct coredump_params *p,
1491     void *tmpbuf)
1492 {
1493 	int error;
1494 
1495 	if (p->comp != NULL)
1496 		return (compress_chunk(p, base, tmpbuf, len));
1497 
1498 	/*
1499 	 * EFAULT is a non-fatal error that we can get, for example,
1500 	 * if the segment is backed by a file but extends beyond its
1501 	 * end.
1502 	 */
1503 	error = core_write(p, base, len, offset, UIO_USERSPACE);
1504 	if (error == EFAULT) {
1505 		log(LOG_WARNING, "Failed to fully fault in a core file segment "
1506 		    "at VA %p with size 0x%zx to be written at offset 0x%jx "
1507 		    "for process %s\n", base, len, offset, curproc->p_comm);
1508 
1509 		/*
1510 		 * Write a "real" zero byte at the end of the target region
1511 		 * in the case this is the last segment.
1512 		 * The intermediate space will be implicitly zero-filled.
1513 		 */
1514 		error = core_write(p, zero_region, 1, offset + len - 1,
1515 		    UIO_SYSSPACE);
1516 	}
1517 	return (error);
1518 }
1519 
1520 /*
1521  * Drain into a core file.
1522  */
1523 static int
1524 sbuf_drain_core_output(void *arg, const char *data, int len)
1525 {
1526 	struct coredump_params *p;
1527 	int error, locked;
1528 
1529 	p = (struct coredump_params *)arg;
1530 
1531 	/*
1532 	 * Some kern_proc out routines that print to this sbuf may
1533 	 * call us with the process lock held. Draining with the
1534 	 * non-sleepable lock held is unsafe. The lock is needed for
1535 	 * those routines when dumping a live process. In our case we
1536 	 * can safely release the lock before draining and acquire
1537 	 * again after.
1538 	 */
1539 	locked = PROC_LOCKED(p->td->td_proc);
1540 	if (locked)
1541 		PROC_UNLOCK(p->td->td_proc);
1542 	if (p->comp != NULL)
1543 		error = compressor_write(p->comp, __DECONST(char *, data), len);
1544 	else
1545 		error = core_write(p, __DECONST(void *, data), len, p->offset,
1546 		    UIO_SYSSPACE);
1547 	if (locked)
1548 		PROC_LOCK(p->td->td_proc);
1549 	if (error != 0)
1550 		return (-error);
1551 	p->offset += len;
1552 	return (len);
1553 }
1554 
1555 /*
1556  * Drain into a counter.
1557  */
1558 static int
1559 sbuf_drain_count(void *arg, const char *data __unused, int len)
1560 {
1561 	size_t *sizep;
1562 
1563 	sizep = (size_t *)arg;
1564 	*sizep += len;
1565 	return (len);
1566 }
1567 
1568 int
1569 __elfN(coredump)(struct thread *td, struct vnode *vp, off_t limit, int flags)
1570 {
1571 	struct ucred *cred = td->td_ucred;
1572 	int error = 0;
1573 	struct sseg_closure seginfo;
1574 	struct note_info_list notelst;
1575 	struct coredump_params params;
1576 	struct note_info *ninfo;
1577 	void *hdr, *tmpbuf;
1578 	size_t hdrsize, notesz, coresize;
1579 
1580 	hdr = NULL;
1581 	tmpbuf = NULL;
1582 	TAILQ_INIT(&notelst);
1583 
1584 	/* Size the program segments. */
1585 	seginfo.count = 0;
1586 	seginfo.size = 0;
1587 	each_dumpable_segment(td, cb_size_segment, &seginfo);
1588 
1589 	/*
1590 	 * Collect info about the core file header area.
1591 	 */
1592 	hdrsize = sizeof(Elf_Ehdr) + sizeof(Elf_Phdr) * (1 + seginfo.count);
1593 	if (seginfo.count + 1 >= PN_XNUM)
1594 		hdrsize += sizeof(Elf_Shdr);
1595 	__elfN(prepare_notes)(td, &notelst, &notesz);
1596 	coresize = round_page(hdrsize + notesz) + seginfo.size;
1597 
1598 	/* Set up core dump parameters. */
1599 	params.offset = 0;
1600 	params.active_cred = cred;
1601 	params.file_cred = NOCRED;
1602 	params.td = td;
1603 	params.vp = vp;
1604 	params.comp = NULL;
1605 
1606 #ifdef RACCT
1607 	if (racct_enable) {
1608 		PROC_LOCK(td->td_proc);
1609 		error = racct_add(td->td_proc, RACCT_CORE, coresize);
1610 		PROC_UNLOCK(td->td_proc);
1611 		if (error != 0) {
1612 			error = EFAULT;
1613 			goto done;
1614 		}
1615 	}
1616 #endif
1617 	if (coresize >= limit) {
1618 		error = EFAULT;
1619 		goto done;
1620 	}
1621 
1622 	/* Create a compression stream if necessary. */
1623 	if (compress_user_cores != 0) {
1624 		params.comp = compressor_init(core_compressed_write,
1625 		    compress_user_cores, CORE_BUF_SIZE,
1626 		    compress_user_cores_level, &params);
1627 		if (params.comp == NULL) {
1628 			error = EFAULT;
1629 			goto done;
1630 		}
1631 		tmpbuf = malloc(CORE_BUF_SIZE, M_TEMP, M_WAITOK | M_ZERO);
1632         }
1633 
1634 	/*
1635 	 * Allocate memory for building the header, fill it up,
1636 	 * and write it out following the notes.
1637 	 */
1638 	hdr = malloc(hdrsize, M_TEMP, M_WAITOK);
1639 	error = __elfN(corehdr)(&params, seginfo.count, hdr, hdrsize, &notelst,
1640 	    notesz);
1641 
1642 	/* Write the contents of all of the writable segments. */
1643 	if (error == 0) {
1644 		Elf_Phdr *php;
1645 		off_t offset;
1646 		int i;
1647 
1648 		php = (Elf_Phdr *)((char *)hdr + sizeof(Elf_Ehdr)) + 1;
1649 		offset = round_page(hdrsize + notesz);
1650 		for (i = 0; i < seginfo.count; i++) {
1651 			error = core_output((caddr_t)(uintptr_t)php->p_vaddr,
1652 			    php->p_filesz, offset, &params, tmpbuf);
1653 			if (error != 0)
1654 				break;
1655 			offset += php->p_filesz;
1656 			php++;
1657 		}
1658 		if (error == 0 && params.comp != NULL)
1659 			error = compressor_flush(params.comp);
1660 	}
1661 	if (error) {
1662 		log(LOG_WARNING,
1663 		    "Failed to write core file for process %s (error %d)\n",
1664 		    curproc->p_comm, error);
1665 	}
1666 
1667 done:
1668 	free(tmpbuf, M_TEMP);
1669 	if (params.comp != NULL)
1670 		compressor_fini(params.comp);
1671 	while ((ninfo = TAILQ_FIRST(&notelst)) != NULL) {
1672 		TAILQ_REMOVE(&notelst, ninfo, link);
1673 		free(ninfo, M_TEMP);
1674 	}
1675 	if (hdr != NULL)
1676 		free(hdr, M_TEMP);
1677 
1678 	return (error);
1679 }
1680 
1681 /*
1682  * A callback for each_dumpable_segment() to write out the segment's
1683  * program header entry.
1684  */
1685 static void
1686 cb_put_phdr(vm_map_entry_t entry, void *closure)
1687 {
1688 	struct phdr_closure *phc = (struct phdr_closure *)closure;
1689 	Elf_Phdr *phdr = phc->phdr;
1690 
1691 	phc->offset = round_page(phc->offset);
1692 
1693 	phdr->p_type = PT_LOAD;
1694 	phdr->p_offset = phc->offset;
1695 	phdr->p_vaddr = entry->start;
1696 	phdr->p_paddr = 0;
1697 	phdr->p_filesz = phdr->p_memsz = entry->end - entry->start;
1698 	phdr->p_align = PAGE_SIZE;
1699 	phdr->p_flags = __elfN(untrans_prot)(entry->protection);
1700 
1701 	phc->offset += phdr->p_filesz;
1702 	phc->phdr++;
1703 }
1704 
1705 /*
1706  * A callback for each_dumpable_segment() to gather information about
1707  * the number of segments and their total size.
1708  */
1709 static void
1710 cb_size_segment(vm_map_entry_t entry, void *closure)
1711 {
1712 	struct sseg_closure *ssc = (struct sseg_closure *)closure;
1713 
1714 	ssc->count++;
1715 	ssc->size += entry->end - entry->start;
1716 }
1717 
1718 /*
1719  * For each writable segment in the process's memory map, call the given
1720  * function with a pointer to the map entry and some arbitrary
1721  * caller-supplied data.
1722  */
1723 static void
1724 each_dumpable_segment(struct thread *td, segment_callback func, void *closure)
1725 {
1726 	struct proc *p = td->td_proc;
1727 	vm_map_t map = &p->p_vmspace->vm_map;
1728 	vm_map_entry_t entry;
1729 	vm_object_t backing_object, object;
1730 	boolean_t ignore_entry;
1731 
1732 	vm_map_lock_read(map);
1733 	for (entry = map->header.next; entry != &map->header;
1734 	    entry = entry->next) {
1735 		/*
1736 		 * Don't dump inaccessible mappings, deal with legacy
1737 		 * coredump mode.
1738 		 *
1739 		 * Note that read-only segments related to the elf binary
1740 		 * are marked MAP_ENTRY_NOCOREDUMP now so we no longer
1741 		 * need to arbitrarily ignore such segments.
1742 		 */
1743 		if (elf_legacy_coredump) {
1744 			if ((entry->protection & VM_PROT_RW) != VM_PROT_RW)
1745 				continue;
1746 		} else {
1747 			if ((entry->protection & VM_PROT_ALL) == 0)
1748 				continue;
1749 		}
1750 
1751 		/*
1752 		 * Dont include memory segment in the coredump if
1753 		 * MAP_NOCORE is set in mmap(2) or MADV_NOCORE in
1754 		 * madvise(2).  Do not dump submaps (i.e. parts of the
1755 		 * kernel map).
1756 		 */
1757 		if (entry->eflags & (MAP_ENTRY_NOCOREDUMP|MAP_ENTRY_IS_SUB_MAP))
1758 			continue;
1759 
1760 		if ((object = entry->object.vm_object) == NULL)
1761 			continue;
1762 
1763 		/* Ignore memory-mapped devices and such things. */
1764 		VM_OBJECT_RLOCK(object);
1765 		while ((backing_object = object->backing_object) != NULL) {
1766 			VM_OBJECT_RLOCK(backing_object);
1767 			VM_OBJECT_RUNLOCK(object);
1768 			object = backing_object;
1769 		}
1770 		ignore_entry = object->type != OBJT_DEFAULT &&
1771 		    object->type != OBJT_SWAP && object->type != OBJT_VNODE &&
1772 		    object->type != OBJT_PHYS;
1773 		VM_OBJECT_RUNLOCK(object);
1774 		if (ignore_entry)
1775 			continue;
1776 
1777 		(*func)(entry, closure);
1778 	}
1779 	vm_map_unlock_read(map);
1780 }
1781 
1782 /*
1783  * Write the core file header to the file, including padding up to
1784  * the page boundary.
1785  */
1786 static int
1787 __elfN(corehdr)(struct coredump_params *p, int numsegs, void *hdr,
1788     size_t hdrsize, struct note_info_list *notelst, size_t notesz)
1789 {
1790 	struct note_info *ninfo;
1791 	struct sbuf *sb;
1792 	int error;
1793 
1794 	/* Fill in the header. */
1795 	bzero(hdr, hdrsize);
1796 	__elfN(puthdr)(p->td, hdr, hdrsize, numsegs, notesz);
1797 
1798 	sb = sbuf_new(NULL, NULL, CORE_BUF_SIZE, SBUF_FIXEDLEN);
1799 	sbuf_set_drain(sb, sbuf_drain_core_output, p);
1800 	sbuf_start_section(sb, NULL);
1801 	sbuf_bcat(sb, hdr, hdrsize);
1802 	TAILQ_FOREACH(ninfo, notelst, link)
1803 	    __elfN(putnote)(ninfo, sb);
1804 	/* Align up to a page boundary for the program segments. */
1805 	sbuf_end_section(sb, -1, PAGE_SIZE, 0);
1806 	error = sbuf_finish(sb);
1807 	sbuf_delete(sb);
1808 
1809 	return (error);
1810 }
1811 
1812 static void
1813 __elfN(prepare_notes)(struct thread *td, struct note_info_list *list,
1814     size_t *sizep)
1815 {
1816 	struct proc *p;
1817 	struct thread *thr;
1818 	size_t size;
1819 
1820 	p = td->td_proc;
1821 	size = 0;
1822 
1823 	size += register_note(list, NT_PRPSINFO, __elfN(note_prpsinfo), p);
1824 
1825 	/*
1826 	 * To have the debugger select the right thread (LWP) as the initial
1827 	 * thread, we dump the state of the thread passed to us in td first.
1828 	 * This is the thread that causes the core dump and thus likely to
1829 	 * be the right thread one wants to have selected in the debugger.
1830 	 */
1831 	thr = td;
1832 	while (thr != NULL) {
1833 		size += register_note(list, NT_PRSTATUS,
1834 		    __elfN(note_prstatus), thr);
1835 		size += register_note(list, NT_FPREGSET,
1836 		    __elfN(note_fpregset), thr);
1837 		size += register_note(list, NT_THRMISC,
1838 		    __elfN(note_thrmisc), thr);
1839 		size += register_note(list, NT_PTLWPINFO,
1840 		    __elfN(note_ptlwpinfo), thr);
1841 		size += register_note(list, -1,
1842 		    __elfN(note_threadmd), thr);
1843 
1844 		thr = (thr == td) ? TAILQ_FIRST(&p->p_threads) :
1845 		    TAILQ_NEXT(thr, td_plist);
1846 		if (thr == td)
1847 			thr = TAILQ_NEXT(thr, td_plist);
1848 	}
1849 
1850 	size += register_note(list, NT_PROCSTAT_PROC,
1851 	    __elfN(note_procstat_proc), p);
1852 	size += register_note(list, NT_PROCSTAT_FILES,
1853 	    note_procstat_files, p);
1854 	size += register_note(list, NT_PROCSTAT_VMMAP,
1855 	    note_procstat_vmmap, p);
1856 	size += register_note(list, NT_PROCSTAT_GROUPS,
1857 	    note_procstat_groups, p);
1858 	size += register_note(list, NT_PROCSTAT_UMASK,
1859 	    note_procstat_umask, p);
1860 	size += register_note(list, NT_PROCSTAT_RLIMIT,
1861 	    note_procstat_rlimit, p);
1862 	size += register_note(list, NT_PROCSTAT_OSREL,
1863 	    note_procstat_osrel, p);
1864 	size += register_note(list, NT_PROCSTAT_PSSTRINGS,
1865 	    __elfN(note_procstat_psstrings), p);
1866 	size += register_note(list, NT_PROCSTAT_AUXV,
1867 	    __elfN(note_procstat_auxv), p);
1868 
1869 	*sizep = size;
1870 }
1871 
1872 static void
1873 __elfN(puthdr)(struct thread *td, void *hdr, size_t hdrsize, int numsegs,
1874     size_t notesz)
1875 {
1876 	Elf_Ehdr *ehdr;
1877 	Elf_Phdr *phdr;
1878 	Elf_Shdr *shdr;
1879 	struct phdr_closure phc;
1880 
1881 	ehdr = (Elf_Ehdr *)hdr;
1882 
1883 	ehdr->e_ident[EI_MAG0] = ELFMAG0;
1884 	ehdr->e_ident[EI_MAG1] = ELFMAG1;
1885 	ehdr->e_ident[EI_MAG2] = ELFMAG2;
1886 	ehdr->e_ident[EI_MAG3] = ELFMAG3;
1887 	ehdr->e_ident[EI_CLASS] = ELF_CLASS;
1888 	ehdr->e_ident[EI_DATA] = ELF_DATA;
1889 	ehdr->e_ident[EI_VERSION] = EV_CURRENT;
1890 	ehdr->e_ident[EI_OSABI] = ELFOSABI_FREEBSD;
1891 	ehdr->e_ident[EI_ABIVERSION] = 0;
1892 	ehdr->e_ident[EI_PAD] = 0;
1893 	ehdr->e_type = ET_CORE;
1894 	ehdr->e_machine = td->td_proc->p_elf_machine;
1895 	ehdr->e_version = EV_CURRENT;
1896 	ehdr->e_entry = 0;
1897 	ehdr->e_phoff = sizeof(Elf_Ehdr);
1898 	ehdr->e_flags = td->td_proc->p_elf_flags;
1899 	ehdr->e_ehsize = sizeof(Elf_Ehdr);
1900 	ehdr->e_phentsize = sizeof(Elf_Phdr);
1901 	ehdr->e_shentsize = sizeof(Elf_Shdr);
1902 	ehdr->e_shstrndx = SHN_UNDEF;
1903 	if (numsegs + 1 < PN_XNUM) {
1904 		ehdr->e_phnum = numsegs + 1;
1905 		ehdr->e_shnum = 0;
1906 	} else {
1907 		ehdr->e_phnum = PN_XNUM;
1908 		ehdr->e_shnum = 1;
1909 
1910 		ehdr->e_shoff = ehdr->e_phoff +
1911 		    (numsegs + 1) * ehdr->e_phentsize;
1912 		KASSERT(ehdr->e_shoff == hdrsize - sizeof(Elf_Shdr),
1913 		    ("e_shoff: %zu, hdrsize - shdr: %zu",
1914 		     (size_t)ehdr->e_shoff, hdrsize - sizeof(Elf_Shdr)));
1915 
1916 		shdr = (Elf_Shdr *)((char *)hdr + ehdr->e_shoff);
1917 		memset(shdr, 0, sizeof(*shdr));
1918 		/*
1919 		 * A special first section is used to hold large segment and
1920 		 * section counts.  This was proposed by Sun Microsystems in
1921 		 * Solaris and has been adopted by Linux; the standard ELF
1922 		 * tools are already familiar with the technique.
1923 		 *
1924 		 * See table 7-7 of the Solaris "Linker and Libraries Guide"
1925 		 * (or 12-7 depending on the version of the document) for more
1926 		 * details.
1927 		 */
1928 		shdr->sh_type = SHT_NULL;
1929 		shdr->sh_size = ehdr->e_shnum;
1930 		shdr->sh_link = ehdr->e_shstrndx;
1931 		shdr->sh_info = numsegs + 1;
1932 	}
1933 
1934 	/*
1935 	 * Fill in the program header entries.
1936 	 */
1937 	phdr = (Elf_Phdr *)((char *)hdr + ehdr->e_phoff);
1938 
1939 	/* The note segement. */
1940 	phdr->p_type = PT_NOTE;
1941 	phdr->p_offset = hdrsize;
1942 	phdr->p_vaddr = 0;
1943 	phdr->p_paddr = 0;
1944 	phdr->p_filesz = notesz;
1945 	phdr->p_memsz = 0;
1946 	phdr->p_flags = PF_R;
1947 	phdr->p_align = ELF_NOTE_ROUNDSIZE;
1948 	phdr++;
1949 
1950 	/* All the writable segments from the program. */
1951 	phc.phdr = phdr;
1952 	phc.offset = round_page(hdrsize + notesz);
1953 	each_dumpable_segment(td, cb_put_phdr, &phc);
1954 }
1955 
1956 static size_t
1957 register_note(struct note_info_list *list, int type, outfunc_t out, void *arg)
1958 {
1959 	struct note_info *ninfo;
1960 	size_t size, notesize;
1961 
1962 	size = 0;
1963 	out(arg, NULL, &size);
1964 	ninfo = malloc(sizeof(*ninfo), M_TEMP, M_ZERO | M_WAITOK);
1965 	ninfo->type = type;
1966 	ninfo->outfunc = out;
1967 	ninfo->outarg = arg;
1968 	ninfo->outsize = size;
1969 	TAILQ_INSERT_TAIL(list, ninfo, link);
1970 
1971 	if (type == -1)
1972 		return (size);
1973 
1974 	notesize = sizeof(Elf_Note) +		/* note header */
1975 	    roundup2(sizeof(FREEBSD_ABI_VENDOR), ELF_NOTE_ROUNDSIZE) +
1976 						/* note name */
1977 	    roundup2(size, ELF_NOTE_ROUNDSIZE);	/* note description */
1978 
1979 	return (notesize);
1980 }
1981 
1982 static size_t
1983 append_note_data(const void *src, void *dst, size_t len)
1984 {
1985 	size_t padded_len;
1986 
1987 	padded_len = roundup2(len, ELF_NOTE_ROUNDSIZE);
1988 	if (dst != NULL) {
1989 		bcopy(src, dst, len);
1990 		bzero((char *)dst + len, padded_len - len);
1991 	}
1992 	return (padded_len);
1993 }
1994 
1995 size_t
1996 __elfN(populate_note)(int type, void *src, void *dst, size_t size, void **descp)
1997 {
1998 	Elf_Note *note;
1999 	char *buf;
2000 	size_t notesize;
2001 
2002 	buf = dst;
2003 	if (buf != NULL) {
2004 		note = (Elf_Note *)buf;
2005 		note->n_namesz = sizeof(FREEBSD_ABI_VENDOR);
2006 		note->n_descsz = size;
2007 		note->n_type = type;
2008 		buf += sizeof(*note);
2009 		buf += append_note_data(FREEBSD_ABI_VENDOR, buf,
2010 		    sizeof(FREEBSD_ABI_VENDOR));
2011 		append_note_data(src, buf, size);
2012 		if (descp != NULL)
2013 			*descp = buf;
2014 	}
2015 
2016 	notesize = sizeof(Elf_Note) +		/* note header */
2017 	    roundup2(sizeof(FREEBSD_ABI_VENDOR), ELF_NOTE_ROUNDSIZE) +
2018 						/* note name */
2019 	    roundup2(size, ELF_NOTE_ROUNDSIZE);	/* note description */
2020 
2021 	return (notesize);
2022 }
2023 
2024 static void
2025 __elfN(putnote)(struct note_info *ninfo, struct sbuf *sb)
2026 {
2027 	Elf_Note note;
2028 	ssize_t old_len, sect_len;
2029 	size_t new_len, descsz, i;
2030 
2031 	if (ninfo->type == -1) {
2032 		ninfo->outfunc(ninfo->outarg, sb, &ninfo->outsize);
2033 		return;
2034 	}
2035 
2036 	note.n_namesz = sizeof(FREEBSD_ABI_VENDOR);
2037 	note.n_descsz = ninfo->outsize;
2038 	note.n_type = ninfo->type;
2039 
2040 	sbuf_bcat(sb, &note, sizeof(note));
2041 	sbuf_start_section(sb, &old_len);
2042 	sbuf_bcat(sb, FREEBSD_ABI_VENDOR, sizeof(FREEBSD_ABI_VENDOR));
2043 	sbuf_end_section(sb, old_len, ELF_NOTE_ROUNDSIZE, 0);
2044 	if (note.n_descsz == 0)
2045 		return;
2046 	sbuf_start_section(sb, &old_len);
2047 	ninfo->outfunc(ninfo->outarg, sb, &ninfo->outsize);
2048 	sect_len = sbuf_end_section(sb, old_len, ELF_NOTE_ROUNDSIZE, 0);
2049 	if (sect_len < 0)
2050 		return;
2051 
2052 	new_len = (size_t)sect_len;
2053 	descsz = roundup(note.n_descsz, ELF_NOTE_ROUNDSIZE);
2054 	if (new_len < descsz) {
2055 		/*
2056 		 * It is expected that individual note emitters will correctly
2057 		 * predict their expected output size and fill up to that size
2058 		 * themselves, padding in a format-specific way if needed.
2059 		 * However, in case they don't, just do it here with zeros.
2060 		 */
2061 		for (i = 0; i < descsz - new_len; i++)
2062 			sbuf_putc(sb, 0);
2063 	} else if (new_len > descsz) {
2064 		/*
2065 		 * We can't always truncate sb -- we may have drained some
2066 		 * of it already.
2067 		 */
2068 		KASSERT(new_len == descsz, ("%s: Note type %u changed as we "
2069 		    "read it (%zu > %zu).  Since it is longer than "
2070 		    "expected, this coredump's notes are corrupt.  THIS "
2071 		    "IS A BUG in the note_procstat routine for type %u.\n",
2072 		    __func__, (unsigned)note.n_type, new_len, descsz,
2073 		    (unsigned)note.n_type));
2074 	}
2075 }
2076 
2077 /*
2078  * Miscellaneous note out functions.
2079  */
2080 
2081 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32
2082 #include <compat/freebsd32/freebsd32.h>
2083 #include <compat/freebsd32/freebsd32_signal.h>
2084 
2085 typedef struct prstatus32 elf_prstatus_t;
2086 typedef struct prpsinfo32 elf_prpsinfo_t;
2087 typedef struct fpreg32 elf_prfpregset_t;
2088 typedef struct fpreg32 elf_fpregset_t;
2089 typedef struct reg32 elf_gregset_t;
2090 typedef struct thrmisc32 elf_thrmisc_t;
2091 #define ELF_KERN_PROC_MASK	KERN_PROC_MASK32
2092 typedef struct kinfo_proc32 elf_kinfo_proc_t;
2093 typedef uint32_t elf_ps_strings_t;
2094 #else
2095 typedef prstatus_t elf_prstatus_t;
2096 typedef prpsinfo_t elf_prpsinfo_t;
2097 typedef prfpregset_t elf_prfpregset_t;
2098 typedef prfpregset_t elf_fpregset_t;
2099 typedef gregset_t elf_gregset_t;
2100 typedef thrmisc_t elf_thrmisc_t;
2101 #define ELF_KERN_PROC_MASK	0
2102 typedef struct kinfo_proc elf_kinfo_proc_t;
2103 typedef vm_offset_t elf_ps_strings_t;
2104 #endif
2105 
2106 static void
2107 __elfN(note_prpsinfo)(void *arg, struct sbuf *sb, size_t *sizep)
2108 {
2109 	struct sbuf sbarg;
2110 	size_t len;
2111 	char *cp, *end;
2112 	struct proc *p;
2113 	elf_prpsinfo_t *psinfo;
2114 	int error;
2115 
2116 	p = (struct proc *)arg;
2117 	if (sb != NULL) {
2118 		KASSERT(*sizep == sizeof(*psinfo), ("invalid size"));
2119 		psinfo = malloc(sizeof(*psinfo), M_TEMP, M_ZERO | M_WAITOK);
2120 		psinfo->pr_version = PRPSINFO_VERSION;
2121 		psinfo->pr_psinfosz = sizeof(elf_prpsinfo_t);
2122 		strlcpy(psinfo->pr_fname, p->p_comm, sizeof(psinfo->pr_fname));
2123 		PROC_LOCK(p);
2124 		if (p->p_args != NULL) {
2125 			len = sizeof(psinfo->pr_psargs) - 1;
2126 			if (len > p->p_args->ar_length)
2127 				len = p->p_args->ar_length;
2128 			memcpy(psinfo->pr_psargs, p->p_args->ar_args, len);
2129 			PROC_UNLOCK(p);
2130 			error = 0;
2131 		} else {
2132 			_PHOLD(p);
2133 			PROC_UNLOCK(p);
2134 			sbuf_new(&sbarg, psinfo->pr_psargs,
2135 			    sizeof(psinfo->pr_psargs), SBUF_FIXEDLEN);
2136 			error = proc_getargv(curthread, p, &sbarg);
2137 			PRELE(p);
2138 			if (sbuf_finish(&sbarg) == 0)
2139 				len = sbuf_len(&sbarg) - 1;
2140 			else
2141 				len = sizeof(psinfo->pr_psargs) - 1;
2142 			sbuf_delete(&sbarg);
2143 		}
2144 		if (error || len == 0)
2145 			strlcpy(psinfo->pr_psargs, p->p_comm,
2146 			    sizeof(psinfo->pr_psargs));
2147 		else {
2148 			KASSERT(len < sizeof(psinfo->pr_psargs),
2149 			    ("len is too long: %zu vs %zu", len,
2150 			    sizeof(psinfo->pr_psargs)));
2151 			cp = psinfo->pr_psargs;
2152 			end = cp + len - 1;
2153 			for (;;) {
2154 				cp = memchr(cp, '\0', end - cp);
2155 				if (cp == NULL)
2156 					break;
2157 				*cp = ' ';
2158 			}
2159 		}
2160 		psinfo->pr_pid = p->p_pid;
2161 		sbuf_bcat(sb, psinfo, sizeof(*psinfo));
2162 		free(psinfo, M_TEMP);
2163 	}
2164 	*sizep = sizeof(*psinfo);
2165 }
2166 
2167 static void
2168 __elfN(note_prstatus)(void *arg, struct sbuf *sb, size_t *sizep)
2169 {
2170 	struct thread *td;
2171 	elf_prstatus_t *status;
2172 
2173 	td = (struct thread *)arg;
2174 	if (sb != NULL) {
2175 		KASSERT(*sizep == sizeof(*status), ("invalid size"));
2176 		status = malloc(sizeof(*status), M_TEMP, M_ZERO | M_WAITOK);
2177 		status->pr_version = PRSTATUS_VERSION;
2178 		status->pr_statussz = sizeof(elf_prstatus_t);
2179 		status->pr_gregsetsz = sizeof(elf_gregset_t);
2180 		status->pr_fpregsetsz = sizeof(elf_fpregset_t);
2181 		status->pr_osreldate = osreldate;
2182 		status->pr_cursig = td->td_proc->p_sig;
2183 		status->pr_pid = td->td_tid;
2184 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32
2185 		fill_regs32(td, &status->pr_reg);
2186 #else
2187 		fill_regs(td, &status->pr_reg);
2188 #endif
2189 		sbuf_bcat(sb, status, sizeof(*status));
2190 		free(status, M_TEMP);
2191 	}
2192 	*sizep = sizeof(*status);
2193 }
2194 
2195 static void
2196 __elfN(note_fpregset)(void *arg, struct sbuf *sb, size_t *sizep)
2197 {
2198 	struct thread *td;
2199 	elf_prfpregset_t *fpregset;
2200 
2201 	td = (struct thread *)arg;
2202 	if (sb != NULL) {
2203 		KASSERT(*sizep == sizeof(*fpregset), ("invalid size"));
2204 		fpregset = malloc(sizeof(*fpregset), M_TEMP, M_ZERO | M_WAITOK);
2205 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32
2206 		fill_fpregs32(td, fpregset);
2207 #else
2208 		fill_fpregs(td, fpregset);
2209 #endif
2210 		sbuf_bcat(sb, fpregset, sizeof(*fpregset));
2211 		free(fpregset, M_TEMP);
2212 	}
2213 	*sizep = sizeof(*fpregset);
2214 }
2215 
2216 static void
2217 __elfN(note_thrmisc)(void *arg, struct sbuf *sb, size_t *sizep)
2218 {
2219 	struct thread *td;
2220 	elf_thrmisc_t thrmisc;
2221 
2222 	td = (struct thread *)arg;
2223 	if (sb != NULL) {
2224 		KASSERT(*sizep == sizeof(thrmisc), ("invalid size"));
2225 		bzero(&thrmisc._pad, sizeof(thrmisc._pad));
2226 		strcpy(thrmisc.pr_tname, td->td_name);
2227 		sbuf_bcat(sb, &thrmisc, sizeof(thrmisc));
2228 	}
2229 	*sizep = sizeof(thrmisc);
2230 }
2231 
2232 static void
2233 __elfN(note_ptlwpinfo)(void *arg, struct sbuf *sb, size_t *sizep)
2234 {
2235 	struct thread *td;
2236 	size_t size;
2237 	int structsize;
2238 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32
2239 	struct ptrace_lwpinfo32 pl;
2240 #else
2241 	struct ptrace_lwpinfo pl;
2242 #endif
2243 
2244 	td = (struct thread *)arg;
2245 	size = sizeof(structsize) + sizeof(pl);
2246 	if (sb != NULL) {
2247 		KASSERT(*sizep == size, ("invalid size"));
2248 		structsize = sizeof(pl);
2249 		sbuf_bcat(sb, &structsize, sizeof(structsize));
2250 		bzero(&pl, sizeof(pl));
2251 		pl.pl_lwpid = td->td_tid;
2252 		pl.pl_event = PL_EVENT_NONE;
2253 		pl.pl_sigmask = td->td_sigmask;
2254 		pl.pl_siglist = td->td_siglist;
2255 		if (td->td_si.si_signo != 0) {
2256 			pl.pl_event = PL_EVENT_SIGNAL;
2257 			pl.pl_flags |= PL_FLAG_SI;
2258 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32
2259 			siginfo_to_siginfo32(&td->td_si, &pl.pl_siginfo);
2260 #else
2261 			pl.pl_siginfo = td->td_si;
2262 #endif
2263 		}
2264 		strcpy(pl.pl_tdname, td->td_name);
2265 		/* XXX TODO: supply more information in struct ptrace_lwpinfo*/
2266 		sbuf_bcat(sb, &pl, sizeof(pl));
2267 	}
2268 	*sizep = size;
2269 }
2270 
2271 /*
2272  * Allow for MD specific notes, as well as any MD
2273  * specific preparations for writing MI notes.
2274  */
2275 static void
2276 __elfN(note_threadmd)(void *arg, struct sbuf *sb, size_t *sizep)
2277 {
2278 	struct thread *td;
2279 	void *buf;
2280 	size_t size;
2281 
2282 	td = (struct thread *)arg;
2283 	size = *sizep;
2284 	if (size != 0 && sb != NULL)
2285 		buf = malloc(size, M_TEMP, M_ZERO | M_WAITOK);
2286 	else
2287 		buf = NULL;
2288 	size = 0;
2289 	__elfN(dump_thread)(td, buf, &size);
2290 	KASSERT(sb == NULL || *sizep == size, ("invalid size"));
2291 	if (size != 0 && sb != NULL)
2292 		sbuf_bcat(sb, buf, size);
2293 	free(buf, M_TEMP);
2294 	*sizep = size;
2295 }
2296 
2297 #ifdef KINFO_PROC_SIZE
2298 CTASSERT(sizeof(struct kinfo_proc) == KINFO_PROC_SIZE);
2299 #endif
2300 
2301 static void
2302 __elfN(note_procstat_proc)(void *arg, struct sbuf *sb, size_t *sizep)
2303 {
2304 	struct proc *p;
2305 	size_t size;
2306 	int structsize;
2307 
2308 	p = (struct proc *)arg;
2309 	size = sizeof(structsize) + p->p_numthreads *
2310 	    sizeof(elf_kinfo_proc_t);
2311 
2312 	if (sb != NULL) {
2313 		KASSERT(*sizep == size, ("invalid size"));
2314 		structsize = sizeof(elf_kinfo_proc_t);
2315 		sbuf_bcat(sb, &structsize, sizeof(structsize));
2316 		PROC_LOCK(p);
2317 		kern_proc_out(p, sb, ELF_KERN_PROC_MASK);
2318 	}
2319 	*sizep = size;
2320 }
2321 
2322 #ifdef KINFO_FILE_SIZE
2323 CTASSERT(sizeof(struct kinfo_file) == KINFO_FILE_SIZE);
2324 #endif
2325 
2326 static void
2327 note_procstat_files(void *arg, struct sbuf *sb, size_t *sizep)
2328 {
2329 	struct proc *p;
2330 	size_t size, sect_sz, i;
2331 	ssize_t start_len, sect_len;
2332 	int structsize, filedesc_flags;
2333 
2334 	if (coredump_pack_fileinfo)
2335 		filedesc_flags = KERN_FILEDESC_PACK_KINFO;
2336 	else
2337 		filedesc_flags = 0;
2338 
2339 	p = (struct proc *)arg;
2340 	structsize = sizeof(struct kinfo_file);
2341 	if (sb == NULL) {
2342 		size = 0;
2343 		sb = sbuf_new(NULL, NULL, 128, SBUF_FIXEDLEN);
2344 		sbuf_set_drain(sb, sbuf_drain_count, &size);
2345 		sbuf_bcat(sb, &structsize, sizeof(structsize));
2346 		PROC_LOCK(p);
2347 		kern_proc_filedesc_out(p, sb, -1, filedesc_flags);
2348 		sbuf_finish(sb);
2349 		sbuf_delete(sb);
2350 		*sizep = size;
2351 	} else {
2352 		sbuf_start_section(sb, &start_len);
2353 
2354 		sbuf_bcat(sb, &structsize, sizeof(structsize));
2355 		PROC_LOCK(p);
2356 		kern_proc_filedesc_out(p, sb, *sizep - sizeof(structsize),
2357 		    filedesc_flags);
2358 
2359 		sect_len = sbuf_end_section(sb, start_len, 0, 0);
2360 		if (sect_len < 0)
2361 			return;
2362 		sect_sz = sect_len;
2363 
2364 		KASSERT(sect_sz <= *sizep,
2365 		    ("kern_proc_filedesc_out did not respect maxlen; "
2366 		     "requested %zu, got %zu", *sizep - sizeof(structsize),
2367 		     sect_sz - sizeof(structsize)));
2368 
2369 		for (i = 0; i < *sizep - sect_sz && sb->s_error == 0; i++)
2370 			sbuf_putc(sb, 0);
2371 	}
2372 }
2373 
2374 #ifdef KINFO_VMENTRY_SIZE
2375 CTASSERT(sizeof(struct kinfo_vmentry) == KINFO_VMENTRY_SIZE);
2376 #endif
2377 
2378 static void
2379 note_procstat_vmmap(void *arg, struct sbuf *sb, size_t *sizep)
2380 {
2381 	struct proc *p;
2382 	size_t size;
2383 	int structsize, vmmap_flags;
2384 
2385 	if (coredump_pack_vmmapinfo)
2386 		vmmap_flags = KERN_VMMAP_PACK_KINFO;
2387 	else
2388 		vmmap_flags = 0;
2389 
2390 	p = (struct proc *)arg;
2391 	structsize = sizeof(struct kinfo_vmentry);
2392 	if (sb == NULL) {
2393 		size = 0;
2394 		sb = sbuf_new(NULL, NULL, 128, SBUF_FIXEDLEN);
2395 		sbuf_set_drain(sb, sbuf_drain_count, &size);
2396 		sbuf_bcat(sb, &structsize, sizeof(structsize));
2397 		PROC_LOCK(p);
2398 		kern_proc_vmmap_out(p, sb, -1, vmmap_flags);
2399 		sbuf_finish(sb);
2400 		sbuf_delete(sb);
2401 		*sizep = size;
2402 	} else {
2403 		sbuf_bcat(sb, &structsize, sizeof(structsize));
2404 		PROC_LOCK(p);
2405 		kern_proc_vmmap_out(p, sb, *sizep - sizeof(structsize),
2406 		    vmmap_flags);
2407 	}
2408 }
2409 
2410 static void
2411 note_procstat_groups(void *arg, struct sbuf *sb, size_t *sizep)
2412 {
2413 	struct proc *p;
2414 	size_t size;
2415 	int structsize;
2416 
2417 	p = (struct proc *)arg;
2418 	size = sizeof(structsize) + p->p_ucred->cr_ngroups * sizeof(gid_t);
2419 	if (sb != NULL) {
2420 		KASSERT(*sizep == size, ("invalid size"));
2421 		structsize = sizeof(gid_t);
2422 		sbuf_bcat(sb, &structsize, sizeof(structsize));
2423 		sbuf_bcat(sb, p->p_ucred->cr_groups, p->p_ucred->cr_ngroups *
2424 		    sizeof(gid_t));
2425 	}
2426 	*sizep = size;
2427 }
2428 
2429 static void
2430 note_procstat_umask(void *arg, struct sbuf *sb, size_t *sizep)
2431 {
2432 	struct proc *p;
2433 	size_t size;
2434 	int structsize;
2435 
2436 	p = (struct proc *)arg;
2437 	size = sizeof(structsize) + sizeof(p->p_fd->fd_cmask);
2438 	if (sb != NULL) {
2439 		KASSERT(*sizep == size, ("invalid size"));
2440 		structsize = sizeof(p->p_fd->fd_cmask);
2441 		sbuf_bcat(sb, &structsize, sizeof(structsize));
2442 		sbuf_bcat(sb, &p->p_fd->fd_cmask, sizeof(p->p_fd->fd_cmask));
2443 	}
2444 	*sizep = size;
2445 }
2446 
2447 static void
2448 note_procstat_rlimit(void *arg, struct sbuf *sb, size_t *sizep)
2449 {
2450 	struct proc *p;
2451 	struct rlimit rlim[RLIM_NLIMITS];
2452 	size_t size;
2453 	int structsize, i;
2454 
2455 	p = (struct proc *)arg;
2456 	size = sizeof(structsize) + sizeof(rlim);
2457 	if (sb != NULL) {
2458 		KASSERT(*sizep == size, ("invalid size"));
2459 		structsize = sizeof(rlim);
2460 		sbuf_bcat(sb, &structsize, sizeof(structsize));
2461 		PROC_LOCK(p);
2462 		for (i = 0; i < RLIM_NLIMITS; i++)
2463 			lim_rlimit_proc(p, i, &rlim[i]);
2464 		PROC_UNLOCK(p);
2465 		sbuf_bcat(sb, rlim, sizeof(rlim));
2466 	}
2467 	*sizep = size;
2468 }
2469 
2470 static void
2471 note_procstat_osrel(void *arg, struct sbuf *sb, size_t *sizep)
2472 {
2473 	struct proc *p;
2474 	size_t size;
2475 	int structsize;
2476 
2477 	p = (struct proc *)arg;
2478 	size = sizeof(structsize) + sizeof(p->p_osrel);
2479 	if (sb != NULL) {
2480 		KASSERT(*sizep == size, ("invalid size"));
2481 		structsize = sizeof(p->p_osrel);
2482 		sbuf_bcat(sb, &structsize, sizeof(structsize));
2483 		sbuf_bcat(sb, &p->p_osrel, sizeof(p->p_osrel));
2484 	}
2485 	*sizep = size;
2486 }
2487 
2488 static void
2489 __elfN(note_procstat_psstrings)(void *arg, struct sbuf *sb, size_t *sizep)
2490 {
2491 	struct proc *p;
2492 	elf_ps_strings_t ps_strings;
2493 	size_t size;
2494 	int structsize;
2495 
2496 	p = (struct proc *)arg;
2497 	size = sizeof(structsize) + sizeof(ps_strings);
2498 	if (sb != NULL) {
2499 		KASSERT(*sizep == size, ("invalid size"));
2500 		structsize = sizeof(ps_strings);
2501 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32
2502 		ps_strings = PTROUT(p->p_sysent->sv_psstrings);
2503 #else
2504 		ps_strings = p->p_sysent->sv_psstrings;
2505 #endif
2506 		sbuf_bcat(sb, &structsize, sizeof(structsize));
2507 		sbuf_bcat(sb, &ps_strings, sizeof(ps_strings));
2508 	}
2509 	*sizep = size;
2510 }
2511 
2512 static void
2513 __elfN(note_procstat_auxv)(void *arg, struct sbuf *sb, size_t *sizep)
2514 {
2515 	struct proc *p;
2516 	size_t size;
2517 	int structsize;
2518 
2519 	p = (struct proc *)arg;
2520 	if (sb == NULL) {
2521 		size = 0;
2522 		sb = sbuf_new(NULL, NULL, 128, SBUF_FIXEDLEN);
2523 		sbuf_set_drain(sb, sbuf_drain_count, &size);
2524 		sbuf_bcat(sb, &structsize, sizeof(structsize));
2525 		PHOLD(p);
2526 		proc_getauxv(curthread, p, sb);
2527 		PRELE(p);
2528 		sbuf_finish(sb);
2529 		sbuf_delete(sb);
2530 		*sizep = size;
2531 	} else {
2532 		structsize = sizeof(Elf_Auxinfo);
2533 		sbuf_bcat(sb, &structsize, sizeof(structsize));
2534 		PHOLD(p);
2535 		proc_getauxv(curthread, p, sb);
2536 		PRELE(p);
2537 	}
2538 }
2539 
2540 static boolean_t
2541 __elfN(parse_notes)(struct image_params *imgp, Elf_Note *checknote,
2542     const char *note_vendor, const Elf_Phdr *pnote,
2543     boolean_t (*cb)(const Elf_Note *, void *, boolean_t *), void *cb_arg)
2544 {
2545 	const Elf_Note *note, *note0, *note_end;
2546 	const char *note_name;
2547 	char *buf;
2548 	int i, error;
2549 	boolean_t res;
2550 
2551 	/* We need some limit, might as well use PAGE_SIZE. */
2552 	if (pnote == NULL || pnote->p_filesz > PAGE_SIZE)
2553 		return (FALSE);
2554 	ASSERT_VOP_LOCKED(imgp->vp, "parse_notes");
2555 	if (pnote->p_offset > PAGE_SIZE ||
2556 	    pnote->p_filesz > PAGE_SIZE - pnote->p_offset) {
2557 		buf = malloc(pnote->p_filesz, M_TEMP, M_NOWAIT);
2558 		if (buf == NULL) {
2559 			VOP_UNLOCK(imgp->vp, 0);
2560 			buf = malloc(pnote->p_filesz, M_TEMP, M_WAITOK);
2561 			vn_lock(imgp->vp, LK_SHARED | LK_RETRY);
2562 		}
2563 		error = vn_rdwr(UIO_READ, imgp->vp, buf, pnote->p_filesz,
2564 		    pnote->p_offset, UIO_SYSSPACE, IO_NODELOCKED,
2565 		    curthread->td_ucred, NOCRED, NULL, curthread);
2566 		if (error != 0) {
2567 			uprintf("i/o error PT_NOTE\n");
2568 			goto retf;
2569 		}
2570 		note = note0 = (const Elf_Note *)buf;
2571 		note_end = (const Elf_Note *)(buf + pnote->p_filesz);
2572 	} else {
2573 		note = note0 = (const Elf_Note *)(imgp->image_header +
2574 		    pnote->p_offset);
2575 		note_end = (const Elf_Note *)(imgp->image_header +
2576 		    pnote->p_offset + pnote->p_filesz);
2577 		buf = NULL;
2578 	}
2579 	for (i = 0; i < 100 && note >= note0 && note < note_end; i++) {
2580 		if (!aligned(note, Elf32_Addr) || (const char *)note_end -
2581 		    (const char *)note < sizeof(Elf_Note)) {
2582 			goto retf;
2583 		}
2584 		if (note->n_namesz != checknote->n_namesz ||
2585 		    note->n_descsz != checknote->n_descsz ||
2586 		    note->n_type != checknote->n_type)
2587 			goto nextnote;
2588 		note_name = (const char *)(note + 1);
2589 		if (note_name + checknote->n_namesz >=
2590 		    (const char *)note_end || strncmp(note_vendor,
2591 		    note_name, checknote->n_namesz) != 0)
2592 			goto nextnote;
2593 
2594 		if (cb(note, cb_arg, &res))
2595 			goto ret;
2596 nextnote:
2597 		note = (const Elf_Note *)((const char *)(note + 1) +
2598 		    roundup2(note->n_namesz, ELF_NOTE_ROUNDSIZE) +
2599 		    roundup2(note->n_descsz, ELF_NOTE_ROUNDSIZE));
2600 	}
2601 retf:
2602 	res = FALSE;
2603 ret:
2604 	free(buf, M_TEMP);
2605 	return (res);
2606 }
2607 
2608 struct brandnote_cb_arg {
2609 	Elf_Brandnote *brandnote;
2610 	int32_t *osrel;
2611 };
2612 
2613 static boolean_t
2614 brandnote_cb(const Elf_Note *note, void *arg0, boolean_t *res)
2615 {
2616 	struct brandnote_cb_arg *arg;
2617 
2618 	arg = arg0;
2619 
2620 	/*
2621 	 * Fetch the osreldate for binary from the ELF OSABI-note if
2622 	 * necessary.
2623 	 */
2624 	*res = (arg->brandnote->flags & BN_TRANSLATE_OSREL) != 0 &&
2625 	    arg->brandnote->trans_osrel != NULL ?
2626 	    arg->brandnote->trans_osrel(note, arg->osrel) : TRUE;
2627 
2628 	return (TRUE);
2629 }
2630 
2631 static Elf_Note fctl_note = {
2632 	.n_namesz = sizeof(FREEBSD_ABI_VENDOR),
2633 	.n_descsz = sizeof(uint32_t),
2634 	.n_type = NT_FREEBSD_FEATURE_CTL,
2635 };
2636 
2637 struct fctl_cb_arg {
2638 	uint32_t *fctl0;
2639 };
2640 
2641 static boolean_t
2642 note_fctl_cb(const Elf_Note *note, void *arg0, boolean_t *res)
2643 {
2644 	struct fctl_cb_arg *arg;
2645 	const Elf32_Word *desc;
2646 	uintptr_t p;
2647 
2648 	arg = arg0;
2649 	p = (uintptr_t)(note + 1);
2650 	p += roundup2(note->n_namesz, ELF_NOTE_ROUNDSIZE);
2651 	desc = (const Elf32_Word *)p;
2652 	*arg->fctl0 = desc[0];
2653 	return (TRUE);
2654 }
2655 
2656 /*
2657  * Try to find the appropriate ABI-note section for checknote, fetch
2658  * the osreldate and feature control flags for binary from the ELF
2659  * OSABI-note.  Only the first page of the image is searched, the same
2660  * as for headers.
2661  */
2662 static boolean_t
2663 __elfN(check_note)(struct image_params *imgp, Elf_Brandnote *brandnote,
2664     int32_t *osrel, uint32_t *fctl0)
2665 {
2666 	const Elf_Phdr *phdr;
2667 	const Elf_Ehdr *hdr;
2668 	struct brandnote_cb_arg b_arg;
2669 	struct fctl_cb_arg f_arg;
2670 	int i, j;
2671 
2672 	hdr = (const Elf_Ehdr *)imgp->image_header;
2673 	phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff);
2674 	b_arg.brandnote = brandnote;
2675 	b_arg.osrel = osrel;
2676 	f_arg.fctl0 = fctl0;
2677 
2678 	for (i = 0; i < hdr->e_phnum; i++) {
2679 		if (phdr[i].p_type == PT_NOTE && __elfN(parse_notes)(imgp,
2680 		    &brandnote->hdr, brandnote->vendor, &phdr[i], brandnote_cb,
2681 		    &b_arg)) {
2682 			for (j = 0; j < hdr->e_phnum; j++) {
2683 				if (phdr[j].p_type == PT_NOTE &&
2684 				    __elfN(parse_notes)(imgp, &fctl_note,
2685 				    FREEBSD_ABI_VENDOR, &phdr[j],
2686 				    note_fctl_cb, &f_arg))
2687 					break;
2688 			}
2689 			return (TRUE);
2690 		}
2691 	}
2692 	return (FALSE);
2693 
2694 }
2695 
2696 /*
2697  * Tell kern_execve.c about it, with a little help from the linker.
2698  */
2699 static struct execsw __elfN(execsw) = {
2700 	.ex_imgact = __CONCAT(exec_, __elfN(imgact)),
2701 	.ex_name = __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE))
2702 };
2703 EXEC_SET(__CONCAT(elf, __ELF_WORD_SIZE), __elfN(execsw));
2704 
2705 static vm_prot_t
2706 __elfN(trans_prot)(Elf_Word flags)
2707 {
2708 	vm_prot_t prot;
2709 
2710 	prot = 0;
2711 	if (flags & PF_X)
2712 		prot |= VM_PROT_EXECUTE;
2713 	if (flags & PF_W)
2714 		prot |= VM_PROT_WRITE;
2715 	if (flags & PF_R)
2716 		prot |= VM_PROT_READ;
2717 #if __ELF_WORD_SIZE == 32 && (defined(__amd64__) || defined(__i386__))
2718 	if (i386_read_exec && (flags & PF_R))
2719 		prot |= VM_PROT_EXECUTE;
2720 #endif
2721 	return (prot);
2722 }
2723 
2724 static Elf_Word
2725 __elfN(untrans_prot)(vm_prot_t prot)
2726 {
2727 	Elf_Word flags;
2728 
2729 	flags = 0;
2730 	if (prot & VM_PROT_EXECUTE)
2731 		flags |= PF_X;
2732 	if (prot & VM_PROT_READ)
2733 		flags |= PF_R;
2734 	if (prot & VM_PROT_WRITE)
2735 		flags |= PF_W;
2736 	return (flags);
2737 }
2738