xref: /freebsd/usr.bin/gcore/elfcore.c (revision 6829dae12bb055451fa467da4589c43bd03b1e64)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2017 Dell EMC
5  * Copyright (c) 2007 Sandvine Incorporated
6  * Copyright (c) 1998 John D. Polstra
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33 
34 #include <sys/endian.h>
35 #include <sys/param.h>
36 #include <sys/procfs.h>
37 #include <sys/ptrace.h>
38 #include <sys/queue.h>
39 #include <sys/linker_set.h>
40 #include <sys/sbuf.h>
41 #include <sys/sysctl.h>
42 #include <sys/user.h>
43 #include <sys/wait.h>
44 #include <machine/elf.h>
45 #include <vm/vm_param.h>
46 #include <vm/vm.h>
47 #include <vm/pmap.h>
48 #include <vm/vm_map.h>
49 #include <assert.h>
50 #include <err.h>
51 #include <errno.h>
52 #include <fcntl.h>
53 #include <stdbool.h>
54 #include <stdint.h>
55 #include <stdio.h>
56 #include <stdlib.h>
57 #include <string.h>
58 #include <unistd.h>
59 #include <libutil.h>
60 
61 #include "extern.h"
62 
63 /*
64  * Code for generating ELF core dumps.
65  */
66 
67 typedef void (*segment_callback)(vm_map_entry_t, void *);
68 
69 /* Closure for cb_put_phdr(). */
70 struct phdr_closure {
71 	Elf_Phdr *phdr;		/* Program header to fill in */
72 	Elf_Off offset;		/* Offset of segment in core file */
73 };
74 
75 /* Closure for cb_size_segment(). */
76 struct sseg_closure {
77 	int count;		/* Count of writable segments. */
78 	size_t size;		/* Total size of all writable segments. */
79 };
80 
81 #ifdef ELFCORE_COMPAT_32
82 typedef struct fpreg32 elfcore_fpregset_t;
83 typedef struct reg32   elfcore_gregset_t;
84 typedef struct prpsinfo32 elfcore_prpsinfo_t;
85 typedef struct prstatus32 elfcore_prstatus_t;
86 typedef struct ptrace_lwpinfo32 elfcore_lwpinfo_t;
87 static void elf_convert_gregset(elfcore_gregset_t *rd, struct reg *rs);
88 static void elf_convert_fpregset(elfcore_fpregset_t *rd, struct fpreg *rs);
89 static void elf_convert_lwpinfo(struct ptrace_lwpinfo32 *pld,
90     struct ptrace_lwpinfo *pls);
91 #else
92 typedef fpregset_t elfcore_fpregset_t;
93 typedef gregset_t  elfcore_gregset_t;
94 typedef prpsinfo_t elfcore_prpsinfo_t;
95 typedef prstatus_t elfcore_prstatus_t;
96 typedef struct ptrace_lwpinfo elfcore_lwpinfo_t;
97 #define elf_convert_gregset(d,s)	*d = *s
98 #define elf_convert_fpregset(d,s)	*d = *s
99 #define	elf_convert_lwpinfo(d,s)	*d = *s
100 #endif
101 
102 typedef void* (*notefunc_t)(void *, size_t *);
103 
104 static void cb_put_phdr(vm_map_entry_t, void *);
105 static void cb_size_segment(vm_map_entry_t, void *);
106 static void each_dumpable_segment(vm_map_entry_t, segment_callback,
107     void *closure);
108 static void elf_detach(void);	/* atexit() handler. */
109 static void *elf_note_fpregset(void *, size_t *);
110 static void *elf_note_prpsinfo(void *, size_t *);
111 static void *elf_note_prstatus(void *, size_t *);
112 static void *elf_note_thrmisc(void *, size_t *);
113 static void *elf_note_ptlwpinfo(void *, size_t *);
114 #if defined(__arm__)
115 static void *elf_note_arm_vfp(void *, size_t *);
116 #endif
117 #if defined(__i386__) || defined(__amd64__)
118 static void *elf_note_x86_xstate(void *, size_t *);
119 #endif
120 #if defined(__powerpc__)
121 static void *elf_note_powerpc_vmx(void *, size_t *);
122 static void *elf_note_powerpc_vsx(void *, size_t *);
123 #endif
124 static void *elf_note_procstat_auxv(void *, size_t *);
125 static void *elf_note_procstat_files(void *, size_t *);
126 static void *elf_note_procstat_groups(void *, size_t *);
127 static void *elf_note_procstat_osrel(void *, size_t *);
128 static void *elf_note_procstat_proc(void *, size_t *);
129 static void *elf_note_procstat_psstrings(void *, size_t *);
130 static void *elf_note_procstat_rlimit(void *, size_t *);
131 static void *elf_note_procstat_umask(void *, size_t *);
132 static void *elf_note_procstat_vmmap(void *, size_t *);
133 static void elf_puthdr(int, pid_t, vm_map_entry_t, void *, size_t, size_t,
134     size_t, int);
135 static void elf_putnote(int, notefunc_t, void *, struct sbuf *);
136 static void elf_putnotes(pid_t, struct sbuf *, size_t *);
137 static void freemap(vm_map_entry_t);
138 static vm_map_entry_t readmap(pid_t);
139 static void *procstat_sysctl(void *, int, size_t, size_t *sizep);
140 
141 static pid_t g_pid;		/* Pid being dumped, global for elf_detach */
142 static int g_status;		/* proc status after ptrace attach */
143 
144 static int
145 elf_ident(int efd, pid_t pid __unused, char *binfile __unused)
146 {
147 	Elf_Ehdr hdr;
148 	int cnt;
149 	uint16_t machine;
150 
151 	cnt = read(efd, &hdr, sizeof(hdr));
152 	if (cnt != sizeof(hdr))
153 		return (0);
154 	if (!IS_ELF(hdr))
155 		return (0);
156 	switch (hdr.e_ident[EI_DATA]) {
157 	case ELFDATA2LSB:
158 		machine = le16toh(hdr.e_machine);
159 		break;
160 	case ELFDATA2MSB:
161 		machine = be16toh(hdr.e_machine);
162 		break;
163 	default:
164 		return (0);
165 	}
166 	if (!ELF_MACHINE_OK(machine))
167 		return (0);
168 
169 	/* Looks good. */
170 	return (1);
171 }
172 
173 static void
174 elf_detach(void)
175 {
176 	int sig;
177 
178 	if (g_pid != 0) {
179 		/*
180 		 * Forward any pending signals. SIGSTOP is generated by ptrace
181 		 * itself, so ignore it.
182 		 */
183 		sig = WIFSTOPPED(g_status) ? WSTOPSIG(g_status) : 0;
184 		if (sig == SIGSTOP)
185 			sig = 0;
186 		ptrace(PT_DETACH, g_pid, (caddr_t)1, sig);
187 	}
188 }
189 
190 /*
191  * Write an ELF coredump for the given pid to the given fd.
192  */
193 static void
194 elf_coredump(int efd, int fd, pid_t pid)
195 {
196 	vm_map_entry_t map;
197 	struct sseg_closure seginfo;
198 	struct sbuf *sb;
199 	void *hdr;
200 	size_t hdrsize, notesz, segoff;
201 	ssize_t n, old_len;
202 	Elf_Phdr *php;
203 	int i;
204 
205 	/* Attach to process to dump. */
206 	g_pid = pid;
207 	if (atexit(elf_detach) != 0)
208 		err(1, "atexit");
209 	errno = 0;
210 	ptrace(PT_ATTACH, pid, NULL, 0);
211 	if (errno)
212 		err(1, "PT_ATTACH");
213 	if (waitpid(pid, &g_status, 0) == -1)
214 		err(1, "waitpid");
215 
216 	/* Get the program's memory map. */
217 	map = readmap(pid);
218 
219 	/* Size the program segments. */
220 	seginfo.count = 0;
221 	seginfo.size = 0;
222 	each_dumpable_segment(map, cb_size_segment, &seginfo);
223 
224 	/*
225 	 * Build the header and the notes using sbuf and write to the file.
226 	 */
227 	sb = sbuf_new_auto();
228 	hdrsize = sizeof(Elf_Ehdr) + sizeof(Elf_Phdr) * (1 + seginfo.count);
229 	if (seginfo.count + 1 >= PN_XNUM)
230 		hdrsize += sizeof(Elf_Shdr);
231 	/* Start header + notes section. */
232 	sbuf_start_section(sb, NULL);
233 	/* Make empty header subsection. */
234 	sbuf_start_section(sb, &old_len);
235 	sbuf_putc(sb, 0);
236 	sbuf_end_section(sb, old_len, hdrsize, 0);
237 	/* Put notes. */
238 	elf_putnotes(pid, sb, &notesz);
239 	/* Align up to a page boundary for the program segments. */
240 	sbuf_end_section(sb, -1, PAGE_SIZE, 0);
241 	if (sbuf_finish(sb) != 0)
242 		err(1, "sbuf_finish");
243 	hdr = sbuf_data(sb);
244 	segoff = sbuf_len(sb);
245 	/* Fill in the header. */
246 	elf_puthdr(efd, pid, map, hdr, hdrsize, notesz, segoff, seginfo.count);
247 
248 	n = write(fd, hdr, segoff);
249 	if (n == -1)
250 		err(1, "write");
251 	if (n < segoff)
252               errx(1, "short write");
253 
254 	/* Write the contents of all of the writable segments. */
255 	php = (Elf_Phdr *)((char *)hdr + sizeof(Elf_Ehdr)) + 1;
256 	for (i = 0;  i < seginfo.count;  i++) {
257 		struct ptrace_io_desc iorequest;
258 		uintmax_t nleft = php->p_filesz;
259 
260 		iorequest.piod_op = PIOD_READ_D;
261 		iorequest.piod_offs = (caddr_t)(uintptr_t)php->p_vaddr;
262 		while (nleft > 0) {
263 			char buf[8*1024];
264 			size_t nwant;
265 			ssize_t ngot;
266 
267 			if (nleft > sizeof(buf))
268 				nwant = sizeof buf;
269 			else
270 				nwant = nleft;
271 			iorequest.piod_addr = buf;
272 			iorequest.piod_len = nwant;
273 			ptrace(PT_IO, pid, (caddr_t)&iorequest, 0);
274 			ngot = iorequest.piod_len;
275 			if ((size_t)ngot < nwant)
276 				errx(1, "short read wanted %zu, got %zd",
277 				    nwant, ngot);
278 			ngot = write(fd, buf, nwant);
279 			if (ngot == -1)
280 				err(1, "write of segment %d failed", i);
281 			if ((size_t)ngot != nwant)
282 				errx(1, "short write");
283 			nleft -= nwant;
284 			iorequest.piod_offs += ngot;
285 		}
286 		php++;
287 	}
288 	sbuf_delete(sb);
289 	freemap(map);
290 }
291 
292 /*
293  * A callback for each_dumpable_segment() to write out the segment's
294  * program header entry.
295  */
296 static void
297 cb_put_phdr(vm_map_entry_t entry, void *closure)
298 {
299 	struct phdr_closure *phc = (struct phdr_closure *)closure;
300 	Elf_Phdr *phdr = phc->phdr;
301 
302 	phc->offset = round_page(phc->offset);
303 
304 	phdr->p_type = PT_LOAD;
305 	phdr->p_offset = phc->offset;
306 	phdr->p_vaddr = entry->start;
307 	phdr->p_paddr = 0;
308 	phdr->p_filesz = phdr->p_memsz = entry->end - entry->start;
309 	phdr->p_align = PAGE_SIZE;
310 	phdr->p_flags = 0;
311 	if (entry->protection & VM_PROT_READ)
312 		phdr->p_flags |= PF_R;
313 	if (entry->protection & VM_PROT_WRITE)
314 		phdr->p_flags |= PF_W;
315 	if (entry->protection & VM_PROT_EXECUTE)
316 		phdr->p_flags |= PF_X;
317 
318 	phc->offset += phdr->p_filesz;
319 	phc->phdr++;
320 }
321 
322 /*
323  * A callback for each_dumpable_segment() to gather information about
324  * the number of segments and their total size.
325  */
326 static void
327 cb_size_segment(vm_map_entry_t entry, void *closure)
328 {
329 	struct sseg_closure *ssc = (struct sseg_closure *)closure;
330 
331 	ssc->count++;
332 	ssc->size += entry->end - entry->start;
333 }
334 
335 /*
336  * For each segment in the given memory map, call the given function
337  * with a pointer to the map entry and some arbitrary caller-supplied
338  * data.
339  */
340 static void
341 each_dumpable_segment(vm_map_entry_t map, segment_callback func, void *closure)
342 {
343 	vm_map_entry_t entry;
344 
345 	for (entry = map;  entry != NULL;  entry = entry->next)
346 		(*func)(entry, closure);
347 }
348 
349 static void
350 elf_putnotes(pid_t pid, struct sbuf *sb, size_t *sizep)
351 {
352 	lwpid_t *tids;
353 	size_t threads, old_len;
354 	ssize_t size;
355 	int i;
356 
357 	errno = 0;
358 	threads = ptrace(PT_GETNUMLWPS, pid, NULL, 0);
359 	if (errno)
360 		err(1, "PT_GETNUMLWPS");
361 	tids = malloc(threads * sizeof(*tids));
362 	if (tids == NULL)
363 		errx(1, "out of memory");
364 	errno = 0;
365 	ptrace(PT_GETLWPLIST, pid, (void *)tids, threads);
366 	if (errno)
367 		err(1, "PT_GETLWPLIST");
368 
369 	sbuf_start_section(sb, &old_len);
370 	elf_putnote(NT_PRPSINFO, elf_note_prpsinfo, &pid, sb);
371 
372 	for (i = 0; i < threads; ++i) {
373 		elf_putnote(NT_PRSTATUS, elf_note_prstatus, tids + i, sb);
374 		elf_putnote(NT_FPREGSET, elf_note_fpregset, tids + i, sb);
375 		elf_putnote(NT_THRMISC, elf_note_thrmisc, tids + i, sb);
376 		elf_putnote(NT_PTLWPINFO, elf_note_ptlwpinfo, tids + i, sb);
377 #if defined(__arm__)
378 		elf_putnote(NT_ARM_VFP, elf_note_arm_vfp, tids + i, sb);
379 #endif
380 #if defined(__i386__) || defined(__amd64__)
381 		elf_putnote(NT_X86_XSTATE, elf_note_x86_xstate, tids + i, sb);
382 #endif
383 #if defined(__powerpc__)
384 		elf_putnote(NT_PPC_VMX, elf_note_powerpc_vmx, tids + i, sb);
385 		elf_putnote(NT_PPC_VSX, elf_note_powerpc_vsx, tids + i, sb);
386 #endif
387 	}
388 
389 #ifndef ELFCORE_COMPAT_32
390 	elf_putnote(NT_PROCSTAT_PROC, elf_note_procstat_proc, &pid, sb);
391 	elf_putnote(NT_PROCSTAT_FILES, elf_note_procstat_files, &pid, sb);
392 	elf_putnote(NT_PROCSTAT_VMMAP, elf_note_procstat_vmmap, &pid, sb);
393 	elf_putnote(NT_PROCSTAT_GROUPS, elf_note_procstat_groups, &pid, sb);
394 	elf_putnote(NT_PROCSTAT_UMASK, elf_note_procstat_umask, &pid, sb);
395 	elf_putnote(NT_PROCSTAT_RLIMIT, elf_note_procstat_rlimit, &pid, sb);
396 	elf_putnote(NT_PROCSTAT_OSREL, elf_note_procstat_osrel, &pid, sb);
397 	elf_putnote(NT_PROCSTAT_PSSTRINGS, elf_note_procstat_psstrings, &pid,
398 	    sb);
399 	elf_putnote(NT_PROCSTAT_AUXV, elf_note_procstat_auxv, &pid, sb);
400 #endif
401 
402 	size = sbuf_end_section(sb, old_len, 1, 0);
403 	if (size == -1)
404 		err(1, "sbuf_end_section");
405 	free(tids);
406 	*sizep = size;
407 }
408 
409 /*
410  * Emit one note section to sbuf.
411  */
412 static void
413 elf_putnote(int type, notefunc_t notefunc, void *arg, struct sbuf *sb)
414 {
415 	Elf_Note note;
416 	size_t descsz;
417 	ssize_t old_len;
418 	void *desc;
419 
420 	desc = notefunc(arg, &descsz);
421 	note.n_namesz = 8; /* strlen("FreeBSD") + 1 */
422 	note.n_descsz = descsz;
423 	note.n_type = type;
424 
425 	sbuf_bcat(sb, &note, sizeof(note));
426 	sbuf_start_section(sb, &old_len);
427 	sbuf_bcat(sb, "FreeBSD", note.n_namesz);
428 	sbuf_end_section(sb, old_len, sizeof(Elf32_Size), 0);
429 	if (descsz == 0)
430 		return;
431 	sbuf_start_section(sb, &old_len);
432 	sbuf_bcat(sb, desc, descsz);
433 	sbuf_end_section(sb, old_len, sizeof(Elf32_Size), 0);
434 	free(desc);
435 }
436 
437 /*
438  * Generate the ELF coredump header.
439  */
440 static void
441 elf_puthdr(int efd, pid_t pid, vm_map_entry_t map, void *hdr, size_t hdrsize,
442     size_t notesz, size_t segoff, int numsegs)
443 {
444 	Elf_Ehdr *ehdr, binhdr;
445 	Elf_Phdr *phdr;
446 	Elf_Shdr *shdr;
447 	struct phdr_closure phc;
448 	ssize_t cnt;
449 
450 	cnt = read(efd, &binhdr, sizeof(binhdr));
451 	if (cnt < 0)
452 		err(1, "Failed to re-read ELF header");
453 	else if (cnt != sizeof(binhdr))
454 		errx(1, "Failed to re-read ELF header");
455 
456 	ehdr = (Elf_Ehdr *)hdr;
457 
458 	ehdr->e_ident[EI_MAG0] = ELFMAG0;
459 	ehdr->e_ident[EI_MAG1] = ELFMAG1;
460 	ehdr->e_ident[EI_MAG2] = ELFMAG2;
461 	ehdr->e_ident[EI_MAG3] = ELFMAG3;
462 	ehdr->e_ident[EI_CLASS] = ELF_CLASS;
463 	ehdr->e_ident[EI_DATA] = ELF_DATA;
464 	ehdr->e_ident[EI_VERSION] = EV_CURRENT;
465 	ehdr->e_ident[EI_OSABI] = ELFOSABI_FREEBSD;
466 	ehdr->e_ident[EI_ABIVERSION] = 0;
467 	ehdr->e_ident[EI_PAD] = 0;
468 	ehdr->e_type = ET_CORE;
469 	ehdr->e_machine = binhdr.e_machine;
470 	ehdr->e_version = EV_CURRENT;
471 	ehdr->e_entry = 0;
472 	ehdr->e_phoff = sizeof(Elf_Ehdr);
473 	ehdr->e_flags = binhdr.e_flags;
474 	ehdr->e_ehsize = sizeof(Elf_Ehdr);
475 	ehdr->e_phentsize = sizeof(Elf_Phdr);
476 	ehdr->e_shentsize = sizeof(Elf_Shdr);
477 	ehdr->e_shstrndx = SHN_UNDEF;
478 	if (numsegs + 1 < PN_XNUM) {
479 		ehdr->e_phnum = numsegs + 1;
480 		ehdr->e_shnum = 0;
481 	} else {
482 		ehdr->e_phnum = PN_XNUM;
483 		ehdr->e_shnum = 1;
484 
485 		ehdr->e_shoff = ehdr->e_phoff +
486 		    (numsegs + 1) * ehdr->e_phentsize;
487 
488 		shdr = (Elf_Shdr *)((char *)hdr + ehdr->e_shoff);
489 		memset(shdr, 0, sizeof(*shdr));
490 		/*
491 		 * A special first section is used to hold large segment and
492 		 * section counts.  This was proposed by Sun Microsystems in
493 		 * Solaris and has been adopted by Linux; the standard ELF
494 		 * tools are already familiar with the technique.
495 		 *
496 		 * See table 7-7 of the Solaris "Linker and Libraries Guide"
497 		 * (or 12-7 depending on the version of the document) for more
498 		 * details.
499 		 */
500 		shdr->sh_type = SHT_NULL;
501 		shdr->sh_size = ehdr->e_shnum;
502 		shdr->sh_link = ehdr->e_shstrndx;
503 		shdr->sh_info = numsegs + 1;
504 	}
505 
506 	/*
507 	 * Fill in the program header entries.
508 	 */
509 	phdr = (Elf_Phdr *)((char *)hdr + ehdr->e_phoff);
510 
511 	/* The note segement. */
512 	phdr->p_type = PT_NOTE;
513 	phdr->p_offset = hdrsize;
514 	phdr->p_vaddr = 0;
515 	phdr->p_paddr = 0;
516 	phdr->p_filesz = notesz;
517 	phdr->p_memsz = 0;
518 	phdr->p_flags = PF_R;
519 	phdr->p_align = sizeof(Elf32_Size);
520 	phdr++;
521 
522 	/* All the writable segments from the program. */
523 	phc.phdr = phdr;
524 	phc.offset = segoff;
525 	each_dumpable_segment(map, cb_put_phdr, &phc);
526 }
527 
528 /*
529  * Free the memory map.
530  */
531 static void
532 freemap(vm_map_entry_t map)
533 {
534 
535 	while (map != NULL) {
536 		vm_map_entry_t next = map->next;
537 		free(map);
538 		map = next;
539 	}
540 }
541 
542 /*
543  * Read the process's memory map using kinfo_getvmmap(), and return a list of
544  * VM map entries.  Only the non-device read/writable segments are
545  * returned.  The map entries in the list aren't fully filled in; only
546  * the items we need are present.
547  */
548 static vm_map_entry_t
549 readmap(pid_t pid)
550 {
551 	vm_map_entry_t ent, *linkp, map;
552 	struct kinfo_vmentry *vmentl, *kve;
553 	int i, nitems;
554 
555 	vmentl = kinfo_getvmmap(pid, &nitems);
556 	if (vmentl == NULL)
557 		err(1, "cannot retrieve mappings for %u process", pid);
558 
559 	map = NULL;
560 	linkp = &map;
561 	for (i = 0; i < nitems; i++) {
562 		kve = &vmentl[i];
563 
564 		/*
565 		 * Ignore 'malformed' segments or ones representing memory
566 		 * mapping with MAP_NOCORE on.
567 		 * If the 'full' support is disabled, just dump the most
568 		 * meaningful data segments.
569 		 */
570 		if ((kve->kve_protection & KVME_PROT_READ) == 0 ||
571 		    (kve->kve_flags & KVME_FLAG_NOCOREDUMP) != 0 ||
572 		    kve->kve_type == KVME_TYPE_DEAD ||
573 		    kve->kve_type == KVME_TYPE_UNKNOWN ||
574 		    ((pflags & PFLAGS_FULL) == 0 &&
575 		    kve->kve_type != KVME_TYPE_DEFAULT &&
576 		    kve->kve_type != KVME_TYPE_VNODE &&
577 		    kve->kve_type != KVME_TYPE_SWAP &&
578 		    kve->kve_type != KVME_TYPE_PHYS))
579 			continue;
580 
581 		ent = calloc(1, sizeof(*ent));
582 		if (ent == NULL)
583 			errx(1, "out of memory");
584 		ent->start = (vm_offset_t)kve->kve_start;
585 		ent->end = (vm_offset_t)kve->kve_end;
586 		ent->protection = VM_PROT_READ | VM_PROT_WRITE;
587 		if ((kve->kve_protection & KVME_PROT_EXEC) != 0)
588 			ent->protection |= VM_PROT_EXECUTE;
589 
590 		*linkp = ent;
591 		linkp = &ent->next;
592 	}
593 	free(vmentl);
594 	return (map);
595 }
596 
597 /*
598  * Miscellaneous note out functions.
599  */
600 
601 static void *
602 elf_note_prpsinfo(void *arg, size_t *sizep)
603 {
604 	char *cp, *end;
605 	pid_t pid;
606 	elfcore_prpsinfo_t *psinfo;
607 	struct kinfo_proc kip;
608 	size_t len;
609 	int name[4];
610 
611 	pid = *(pid_t *)arg;
612 	psinfo = calloc(1, sizeof(*psinfo));
613 	if (psinfo == NULL)
614 		errx(1, "out of memory");
615 	psinfo->pr_version = PRPSINFO_VERSION;
616 	psinfo->pr_psinfosz = sizeof(*psinfo);
617 
618 	name[0] = CTL_KERN;
619 	name[1] = KERN_PROC;
620 	name[2] = KERN_PROC_PID;
621 	name[3] = pid;
622 	len = sizeof(kip);
623 	if (sysctl(name, 4, &kip, &len, NULL, 0) == -1)
624 		err(1, "kern.proc.pid.%u", pid);
625 	if (kip.ki_pid != pid)
626 		err(1, "kern.proc.pid.%u", pid);
627 	strlcpy(psinfo->pr_fname, kip.ki_comm, sizeof(psinfo->pr_fname));
628 	name[2] = KERN_PROC_ARGS;
629 	len = sizeof(psinfo->pr_psargs) - 1;
630 	if (sysctl(name, 4, psinfo->pr_psargs, &len, NULL, 0) == 0 && len > 0) {
631 		cp = psinfo->pr_psargs;
632 		end = cp + len - 1;
633 		for (;;) {
634 			cp = memchr(cp, '\0', end - cp);
635 			if (cp == NULL)
636 				break;
637 			*cp = ' ';
638 		}
639 	} else
640 		strlcpy(psinfo->pr_psargs, kip.ki_comm,
641 		    sizeof(psinfo->pr_psargs));
642 	psinfo->pr_pid = pid;
643 
644 	*sizep = sizeof(*psinfo);
645 	return (psinfo);
646 }
647 
648 static void *
649 elf_note_prstatus(void *arg, size_t *sizep)
650 {
651 	lwpid_t tid;
652 	elfcore_prstatus_t *status;
653 	struct reg greg;
654 
655 	tid = *(lwpid_t *)arg;
656 	status = calloc(1, sizeof(*status));
657 	if (status == NULL)
658 		errx(1, "out of memory");
659 	status->pr_version = PRSTATUS_VERSION;
660 	status->pr_statussz = sizeof(*status);
661 	status->pr_gregsetsz = sizeof(elfcore_gregset_t);
662 	status->pr_fpregsetsz = sizeof(elfcore_fpregset_t);
663 	status->pr_osreldate = __FreeBSD_version;
664 	status->pr_pid = tid;
665 	ptrace(PT_GETREGS, tid, (void *)&greg, 0);
666 	elf_convert_gregset(&status->pr_reg, &greg);
667 
668 	*sizep = sizeof(*status);
669 	return (status);
670 }
671 
672 static void *
673 elf_note_fpregset(void *arg, size_t *sizep)
674 {
675 	lwpid_t tid;
676 	elfcore_fpregset_t *fpregset;
677 	fpregset_t fpreg;
678 
679 	tid = *(lwpid_t *)arg;
680 	fpregset = calloc(1, sizeof(*fpregset));
681 	if (fpregset == NULL)
682 		errx(1, "out of memory");
683 	ptrace(PT_GETFPREGS, tid, (void *)&fpreg, 0);
684 	elf_convert_fpregset(fpregset, &fpreg);
685 
686 	*sizep = sizeof(*fpregset);
687 	return (fpregset);
688 }
689 
690 static void *
691 elf_note_thrmisc(void *arg, size_t *sizep)
692 {
693 	lwpid_t tid;
694 	struct ptrace_lwpinfo lwpinfo;
695 	thrmisc_t *thrmisc;
696 
697 	tid = *(lwpid_t *)arg;
698 	thrmisc = calloc(1, sizeof(*thrmisc));
699 	if (thrmisc == NULL)
700 		errx(1, "out of memory");
701 	ptrace(PT_LWPINFO, tid, (void *)&lwpinfo,
702 	    sizeof(lwpinfo));
703 	memset(&thrmisc->_pad, 0, sizeof(thrmisc->_pad));
704 	strcpy(thrmisc->pr_tname, lwpinfo.pl_tdname);
705 
706 	*sizep = sizeof(*thrmisc);
707 	return (thrmisc);
708 }
709 
710 static void *
711 elf_note_ptlwpinfo(void *arg, size_t *sizep)
712 {
713 	lwpid_t tid;
714 	elfcore_lwpinfo_t *elf_info;
715 	struct ptrace_lwpinfo lwpinfo;
716 	void *p;
717 
718 	tid = *(lwpid_t *)arg;
719 	p = calloc(1, sizeof(int) + sizeof(elfcore_lwpinfo_t));
720 	if (p == NULL)
721 		errx(1, "out of memory");
722 	*(int *)p = sizeof(elfcore_lwpinfo_t);
723 	elf_info = (void *)((int *)p + 1);
724 	ptrace(PT_LWPINFO, tid, (void *)&lwpinfo, sizeof(lwpinfo));
725 	elf_convert_lwpinfo(elf_info, &lwpinfo);
726 
727 	*sizep = sizeof(int) + sizeof(struct ptrace_lwpinfo);
728 	return (p);
729 }
730 
731 #if defined(__arm__)
732 static void *
733 elf_note_arm_vfp(void *arg, size_t *sizep)
734 {
735 	lwpid_t tid;
736 	struct vfpreg *vfp;
737 	static bool has_vfp = true;
738 	struct vfpreg info;
739 
740 	tid = *(lwpid_t *)arg;
741 	if (has_vfp) {
742 		if (ptrace(PT_GETVFPREGS, tid, (void *)&info, 0) != 0)
743 			has_vfp = false;
744 	}
745 	if (!has_vfp) {
746 		*sizep = 0;
747 		return (NULL);
748 	}
749 	vfp = calloc(1, sizeof(*vfp));
750 	memcpy(vfp, &info, sizeof(*vfp));
751 	*sizep = sizeof(*vfp);
752 	return (vfp);
753 }
754 #endif
755 
756 #if defined(__i386__) || defined(__amd64__)
757 static void *
758 elf_note_x86_xstate(void *arg, size_t *sizep)
759 {
760 	lwpid_t tid;
761 	char *xstate;
762 	static bool xsave_checked = false;
763 	static struct ptrace_xstate_info info;
764 
765 	tid = *(lwpid_t *)arg;
766 	if (!xsave_checked) {
767 		if (ptrace(PT_GETXSTATE_INFO, tid, (void *)&info,
768 		    sizeof(info)) != 0)
769 			info.xsave_len = 0;
770 		xsave_checked = true;
771 	}
772 	if (info.xsave_len == 0) {
773 		*sizep = 0;
774 		return (NULL);
775 	}
776 	xstate = calloc(1, info.xsave_len);
777 	ptrace(PT_GETXSTATE, tid, xstate, 0);
778 	*(uint64_t *)(xstate + X86_XSTATE_XCR0_OFFSET) = info.xsave_mask;
779 	*sizep = info.xsave_len;
780 	return (xstate);
781 }
782 #endif
783 
784 #if defined(__powerpc__)
785 static void *
786 elf_note_powerpc_vmx(void *arg, size_t *sizep)
787 {
788 	lwpid_t tid;
789 	struct vmxreg *vmx;
790 	static bool has_vmx = true;
791 	struct vmxreg info;
792 
793 	tid = *(lwpid_t *)arg;
794 	if (has_vmx) {
795 		if (ptrace(PT_GETVRREGS, tid, (void *)&info,
796 		    sizeof(info)) != 0)
797 			has_vmx = false;
798 	}
799 	if (!has_vmx) {
800 		*sizep = 0;
801 		return (NULL);
802 	}
803 	vmx = calloc(1, sizeof(*vmx));
804 	memcpy(vmx, &info, sizeof(*vmx));
805 	*sizep = sizeof(*vmx);
806 	return (vmx);
807 }
808 
809 static void *
810 elf_note_powerpc_vsx(void *arg, size_t *sizep)
811 {
812 	lwpid_t tid;
813 	char *vshr_data;
814 	static bool has_vsx = true;
815 	uint64_t vshr[32];
816 
817 	tid = *(lwpid_t *)arg;
818 	if (has_vsx) {
819 		if (ptrace(PT_GETVSRREGS, tid, (void *)vshr,
820 		    sizeof(vshr)) != 0)
821 			has_vsx = false;
822 	}
823 	if (!has_vsx) {
824 		*sizep = 0;
825 		return (NULL);
826 	}
827 	vshr_data = calloc(1, sizeof(vshr));
828 	memcpy(vshr_data, vshr, sizeof(vshr));
829 	*sizep = sizeof(vshr);
830 	return (vshr_data);
831 }
832 #endif
833 
834 static void *
835 procstat_sysctl(void *arg, int what, size_t structsz, size_t *sizep)
836 {
837 	size_t len;
838 	pid_t pid;
839 	int name[4], structsize;
840 	void *buf, *p;
841 
842 	pid = *(pid_t *)arg;
843 	structsize = structsz;
844 	name[0] = CTL_KERN;
845 	name[1] = KERN_PROC;
846 	name[2] = what;
847 	name[3] = pid;
848 	len = 0;
849 	if (sysctl(name, 4, NULL, &len, NULL, 0) == -1)
850 		err(1, "kern.proc.%d.%u", what, pid);
851 	buf = calloc(1, sizeof(structsize) + len * 4 / 3);
852 	if (buf == NULL)
853 		errx(1, "out of memory");
854 	bcopy(&structsize, buf, sizeof(structsize));
855 	p = (char *)buf + sizeof(structsize);
856 	if (sysctl(name, 4, p, &len, NULL, 0) == -1)
857 		err(1, "kern.proc.%d.%u", what, pid);
858 
859 	*sizep = sizeof(structsize) + len;
860 	return (buf);
861 }
862 
863 static void *
864 elf_note_procstat_proc(void *arg, size_t *sizep)
865 {
866 
867 	return (procstat_sysctl(arg, KERN_PROC_PID | KERN_PROC_INC_THREAD,
868 	    sizeof(struct kinfo_proc), sizep));
869 }
870 
871 static void *
872 elf_note_procstat_files(void *arg, size_t *sizep)
873 {
874 
875 	return (procstat_sysctl(arg, KERN_PROC_FILEDESC,
876 	    sizeof(struct kinfo_file), sizep));
877 }
878 
879 static void *
880 elf_note_procstat_vmmap(void *arg, size_t *sizep)
881 {
882 
883 	return (procstat_sysctl(arg, KERN_PROC_VMMAP,
884 	    sizeof(struct kinfo_vmentry), sizep));
885 }
886 
887 static void *
888 elf_note_procstat_groups(void *arg, size_t *sizep)
889 {
890 
891 	return (procstat_sysctl(arg, KERN_PROC_GROUPS, sizeof(gid_t), sizep));
892 }
893 
894 static void *
895 elf_note_procstat_umask(void *arg, size_t *sizep)
896 {
897 
898 	return (procstat_sysctl(arg, KERN_PROC_UMASK, sizeof(u_short), sizep));
899 }
900 
901 static void *
902 elf_note_procstat_osrel(void *arg, size_t *sizep)
903 {
904 
905 	return (procstat_sysctl(arg, KERN_PROC_OSREL, sizeof(int), sizep));
906 }
907 
908 static void *
909 elf_note_procstat_psstrings(void *arg, size_t *sizep)
910 {
911 
912 	return (procstat_sysctl(arg, KERN_PROC_PS_STRINGS,
913 	    sizeof(vm_offset_t), sizep));
914 }
915 
916 static void *
917 elf_note_procstat_auxv(void *arg, size_t *sizep)
918 {
919 
920 	return (procstat_sysctl(arg, KERN_PROC_AUXV,
921 	    sizeof(Elf_Auxinfo), sizep));
922 }
923 
924 static void *
925 elf_note_procstat_rlimit(void *arg, size_t *sizep)
926 {
927 	pid_t pid;
928 	size_t len;
929 	int i, name[5], structsize;
930 	void *buf, *p;
931 
932 	pid = *(pid_t *)arg;
933 	structsize = sizeof(struct rlimit) * RLIM_NLIMITS;
934 	buf = calloc(1, sizeof(structsize) + structsize);
935 	if (buf == NULL)
936 		errx(1, "out of memory");
937 	bcopy(&structsize, buf, sizeof(structsize));
938 	p = (char *)buf + sizeof(structsize);
939 	name[0] = CTL_KERN;
940 	name[1] = KERN_PROC;
941 	name[2] = KERN_PROC_RLIMIT;
942 	name[3] = pid;
943 	len = sizeof(struct rlimit);
944 	for (i = 0; i < RLIM_NLIMITS; i++) {
945 		name[4] = i;
946 		if (sysctl(name, 5, p, &len, NULL, 0) == -1)
947 			err(1, "kern.proc.rlimit.%u", pid);
948 		if (len != sizeof(struct rlimit))
949 			errx(1, "kern.proc.rlimit.%u: short read", pid);
950 		p += len;
951 	}
952 
953 	*sizep = sizeof(structsize) + structsize;
954 	return (buf);
955 }
956 
957 struct dumpers __elfN(dump) = { elf_ident, elf_coredump };
958 TEXT_SET(dumpset, __elfN(dump));
959