xref: /freebsd/usr.bin/gcore/elfcore.c (revision 3e11bd9e2a2b1cbd4283c87c93e3cc75e3f2dacb)
1 /*-
2  * Copyright (c) 2007 Sandvine Incorporated
3  * Copyright (c) 1998 John D. Polstra
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include <sys/endian.h>
32 #include <sys/param.h>
33 #include <sys/procfs.h>
34 #include <sys/ptrace.h>
35 #include <sys/queue.h>
36 #include <sys/linker_set.h>
37 #include <sys/sbuf.h>
38 #include <sys/sysctl.h>
39 #include <sys/user.h>
40 #include <sys/wait.h>
41 #include <machine/elf.h>
42 #include <vm/vm_param.h>
43 #include <vm/vm.h>
44 #include <vm/pmap.h>
45 #include <vm/vm_map.h>
46 #include <assert.h>
47 #include <err.h>
48 #include <errno.h>
49 #include <fcntl.h>
50 #include <stdbool.h>
51 #include <stdint.h>
52 #include <stdio.h>
53 #include <stdlib.h>
54 #include <string.h>
55 #include <unistd.h>
56 #include <libutil.h>
57 
58 #include "extern.h"
59 
60 /*
61  * Code for generating ELF core dumps.
62  */
63 
64 typedef void (*segment_callback)(vm_map_entry_t, void *);
65 
66 /* Closure for cb_put_phdr(). */
67 struct phdr_closure {
68 	Elf_Phdr *phdr;		/* Program header to fill in */
69 	Elf_Off offset;		/* Offset of segment in core file */
70 };
71 
72 /* Closure for cb_size_segment(). */
73 struct sseg_closure {
74 	int count;		/* Count of writable segments. */
75 	size_t size;		/* Total size of all writable segments. */
76 };
77 
78 #ifdef ELFCORE_COMPAT_32
79 typedef struct fpreg32 elfcore_fpregset_t;
80 typedef struct reg32   elfcore_gregset_t;
81 typedef struct prpsinfo32 elfcore_prpsinfo_t;
82 typedef struct prstatus32 elfcore_prstatus_t;
83 static void elf_convert_gregset(elfcore_gregset_t *rd, struct reg *rs);
84 static void elf_convert_fpregset(elfcore_fpregset_t *rd, struct fpreg *rs);
85 #else
86 typedef fpregset_t elfcore_fpregset_t;
87 typedef gregset_t  elfcore_gregset_t;
88 typedef prpsinfo_t elfcore_prpsinfo_t;
89 typedef prstatus_t elfcore_prstatus_t;
90 #define elf_convert_gregset(d,s)	*d = *s
91 #define elf_convert_fpregset(d,s)	*d = *s
92 #endif
93 
94 typedef void* (*notefunc_t)(void *, size_t *);
95 
96 static void cb_put_phdr(vm_map_entry_t, void *);
97 static void cb_size_segment(vm_map_entry_t, void *);
98 static void each_writable_segment(vm_map_entry_t, segment_callback,
99     void *closure);
100 static void elf_detach(void);	/* atexit() handler. */
101 static void *elf_note_fpregset(void *, size_t *);
102 static void *elf_note_prpsinfo(void *, size_t *);
103 static void *elf_note_prstatus(void *, size_t *);
104 static void *elf_note_thrmisc(void *, size_t *);
105 #if defined(__i386__) || defined(__amd64__)
106 static void *elf_note_x86_xstate(void *, size_t *);
107 #endif
108 static void *elf_note_procstat_auxv(void *, size_t *);
109 static void *elf_note_procstat_files(void *, size_t *);
110 static void *elf_note_procstat_groups(void *, size_t *);
111 static void *elf_note_procstat_osrel(void *, size_t *);
112 static void *elf_note_procstat_proc(void *, size_t *);
113 static void *elf_note_procstat_psstrings(void *, size_t *);
114 static void *elf_note_procstat_rlimit(void *, size_t *);
115 static void *elf_note_procstat_umask(void *, size_t *);
116 static void *elf_note_procstat_vmmap(void *, size_t *);
117 static void elf_puthdr(pid_t, vm_map_entry_t, void *, size_t, size_t, size_t,
118     int);
119 static void elf_putnote(int, notefunc_t, void *, struct sbuf *);
120 static void elf_putnotes(pid_t, struct sbuf *, size_t *);
121 static void freemap(vm_map_entry_t);
122 static vm_map_entry_t readmap(pid_t);
123 static void *procstat_sysctl(void *, int, size_t, size_t *sizep);
124 
125 static pid_t g_pid;		/* Pid being dumped, global for elf_detach */
126 
127 static int
128 elf_ident(int efd, pid_t pid __unused, char *binfile __unused)
129 {
130 	Elf_Ehdr hdr;
131 	int cnt;
132 	uint16_t machine;
133 
134 	cnt = read(efd, &hdr, sizeof(hdr));
135 	if (cnt != sizeof(hdr))
136 		return (0);
137 	if (!IS_ELF(hdr))
138 		return (0);
139 	switch (hdr.e_ident[EI_DATA]) {
140 	case ELFDATA2LSB:
141 		machine = le16toh(hdr.e_machine);
142 		break;
143 	case ELFDATA2MSB:
144 		machine = be16toh(hdr.e_machine);
145 		break;
146 	default:
147 		return (0);
148 	}
149 	if (!ELF_MACHINE_OK(machine))
150 		return (0);
151 
152 	/* Looks good. */
153 	return (1);
154 }
155 
156 static void
157 elf_detach(void)
158 {
159 
160 	if (g_pid != 0)
161 		ptrace(PT_DETACH, g_pid, (caddr_t)1, 0);
162 }
163 
164 /*
165  * Write an ELF coredump for the given pid to the given fd.
166  */
167 static void
168 elf_coredump(int efd __unused, int fd, pid_t pid)
169 {
170 	vm_map_entry_t map;
171 	struct sseg_closure seginfo;
172 	struct sbuf *sb;
173 	void *hdr;
174 	size_t hdrsize, notesz, segoff;
175 	ssize_t n, old_len;
176 	Elf_Phdr *php;
177 	int i;
178 
179 	/* Attach to process to dump. */
180 	g_pid = pid;
181 	if (atexit(elf_detach) != 0)
182 		err(1, "atexit");
183 	errno = 0;
184 	ptrace(PT_ATTACH, pid, NULL, 0);
185 	if (errno)
186 		err(1, "PT_ATTACH");
187 	if (waitpid(pid, NULL, 0) == -1)
188 		err(1, "waitpid");
189 
190 	/* Get the program's memory map. */
191 	map = readmap(pid);
192 
193 	/* Size the program segments. */
194 	seginfo.count = 0;
195 	seginfo.size = 0;
196 	each_writable_segment(map, cb_size_segment, &seginfo);
197 
198 	/*
199 	 * Build the header and the notes using sbuf and write to the file.
200 	 */
201 	sb = sbuf_new_auto();
202 	hdrsize = sizeof(Elf_Ehdr) + sizeof(Elf_Phdr) * (1 + seginfo.count);
203 	/* Start header + notes section. */
204 	sbuf_start_section(sb, NULL);
205 	/* Make empty header subsection. */
206 	sbuf_start_section(sb, &old_len);
207 	sbuf_putc(sb, 0);
208 	sbuf_end_section(sb, old_len, hdrsize, 0);
209 	/* Put notes. */
210 	elf_putnotes(pid, sb, &notesz);
211 	/* Align up to a page boundary for the program segments. */
212 	sbuf_end_section(sb, -1, PAGE_SIZE, 0);
213 	if (sbuf_finish(sb) != 0)
214 		err(1, "sbuf_finish");
215 	hdr = sbuf_data(sb);
216 	segoff = sbuf_len(sb);
217 	/* Fill in the header. */
218 	elf_puthdr(pid, map, hdr, hdrsize, notesz, segoff, seginfo.count);
219 
220 	n = write(fd, hdr, segoff);
221 	if (n == -1)
222 		err(1, "write");
223 	if (n < segoff)
224               errx(1, "short write");
225 
226 	/* Write the contents of all of the writable segments. */
227 	php = (Elf_Phdr *)((char *)hdr + sizeof(Elf_Ehdr)) + 1;
228 	for (i = 0;  i < seginfo.count;  i++) {
229 		struct ptrace_io_desc iorequest;
230 		uintmax_t nleft = php->p_filesz;
231 
232 		iorequest.piod_op = PIOD_READ_D;
233 		iorequest.piod_offs = (caddr_t)(uintptr_t)php->p_vaddr;
234 		while (nleft > 0) {
235 			char buf[8*1024];
236 			size_t nwant;
237 			ssize_t ngot;
238 
239 			if (nleft > sizeof(buf))
240 				nwant = sizeof buf;
241 			else
242 				nwant = nleft;
243 			iorequest.piod_addr = buf;
244 			iorequest.piod_len = nwant;
245 			ptrace(PT_IO, pid, (caddr_t)&iorequest, 0);
246 			ngot = iorequest.piod_len;
247 			if ((size_t)ngot < nwant)
248 				errx(1, "short read wanted %zu, got %zd",
249 				    nwant, ngot);
250 			ngot = write(fd, buf, nwant);
251 			if (ngot == -1)
252 				err(1, "write of segment %d failed", i);
253 			if ((size_t)ngot != nwant)
254 				errx(1, "short write");
255 			nleft -= nwant;
256 			iorequest.piod_offs += ngot;
257 		}
258 		php++;
259 	}
260 	sbuf_delete(sb);
261 	freemap(map);
262 }
263 
264 /*
265  * A callback for each_writable_segment() to write out the segment's
266  * program header entry.
267  */
268 static void
269 cb_put_phdr(vm_map_entry_t entry, void *closure)
270 {
271 	struct phdr_closure *phc = (struct phdr_closure *)closure;
272 	Elf_Phdr *phdr = phc->phdr;
273 
274 	phc->offset = round_page(phc->offset);
275 
276 	phdr->p_type = PT_LOAD;
277 	phdr->p_offset = phc->offset;
278 	phdr->p_vaddr = entry->start;
279 	phdr->p_paddr = 0;
280 	phdr->p_filesz = phdr->p_memsz = entry->end - entry->start;
281 	phdr->p_align = PAGE_SIZE;
282 	phdr->p_flags = 0;
283 	if (entry->protection & VM_PROT_READ)
284 		phdr->p_flags |= PF_R;
285 	if (entry->protection & VM_PROT_WRITE)
286 		phdr->p_flags |= PF_W;
287 	if (entry->protection & VM_PROT_EXECUTE)
288 		phdr->p_flags |= PF_X;
289 
290 	phc->offset += phdr->p_filesz;
291 	phc->phdr++;
292 }
293 
294 /*
295  * A callback for each_writable_segment() to gather information about
296  * the number of segments and their total size.
297  */
298 static void
299 cb_size_segment(vm_map_entry_t entry, void *closure)
300 {
301 	struct sseg_closure *ssc = (struct sseg_closure *)closure;
302 
303 	ssc->count++;
304 	ssc->size += entry->end - entry->start;
305 }
306 
307 /*
308  * For each segment in the given memory map, call the given function
309  * with a pointer to the map entry and some arbitrary caller-supplied
310  * data.
311  */
312 static void
313 each_writable_segment(vm_map_entry_t map, segment_callback func, void *closure)
314 {
315 	vm_map_entry_t entry;
316 
317 	for (entry = map;  entry != NULL;  entry = entry->next)
318 		(*func)(entry, closure);
319 }
320 
321 static void
322 elf_putnotes(pid_t pid, struct sbuf *sb, size_t *sizep)
323 {
324 	lwpid_t *tids;
325 	size_t threads, old_len;
326 	ssize_t size;
327 	int i;
328 
329 	errno = 0;
330 	threads = ptrace(PT_GETNUMLWPS, pid, NULL, 0);
331 	if (errno)
332 		err(1, "PT_GETNUMLWPS");
333 	tids = malloc(threads * sizeof(*tids));
334 	if (tids == NULL)
335 		errx(1, "out of memory");
336 	errno = 0;
337 	ptrace(PT_GETLWPLIST, pid, (void *)tids, threads);
338 	if (errno)
339 		err(1, "PT_GETLWPLIST");
340 
341 	sbuf_start_section(sb, &old_len);
342 	elf_putnote(NT_PRPSINFO, elf_note_prpsinfo, &pid, sb);
343 
344 	for (i = 0; i < threads; ++i) {
345 		elf_putnote(NT_PRSTATUS, elf_note_prstatus, tids + i, sb);
346 		elf_putnote(NT_FPREGSET, elf_note_fpregset, tids + i, sb);
347 		elf_putnote(NT_THRMISC, elf_note_thrmisc, tids + i, sb);
348 #if defined(__i386__) || defined(__amd64__)
349 		elf_putnote(NT_X86_XSTATE, elf_note_x86_xstate, tids + i, sb);
350 #endif
351 	}
352 
353 #ifndef ELFCORE_COMPAT_32
354 	elf_putnote(NT_PROCSTAT_PROC, elf_note_procstat_proc, &pid, sb);
355 	elf_putnote(NT_PROCSTAT_FILES, elf_note_procstat_files, &pid, sb);
356 	elf_putnote(NT_PROCSTAT_VMMAP, elf_note_procstat_vmmap, &pid, sb);
357 	elf_putnote(NT_PROCSTAT_GROUPS, elf_note_procstat_groups, &pid, sb);
358 	elf_putnote(NT_PROCSTAT_UMASK, elf_note_procstat_umask, &pid, sb);
359 	elf_putnote(NT_PROCSTAT_RLIMIT, elf_note_procstat_rlimit, &pid, sb);
360 	elf_putnote(NT_PROCSTAT_OSREL, elf_note_procstat_osrel, &pid, sb);
361 	elf_putnote(NT_PROCSTAT_PSSTRINGS, elf_note_procstat_psstrings, &pid,
362 	    sb);
363 	elf_putnote(NT_PROCSTAT_AUXV, elf_note_procstat_auxv, &pid, sb);
364 #endif
365 
366 	size = sbuf_end_section(sb, old_len, 1, 0);
367 	if (size == -1)
368 		err(1, "sbuf_end_section");
369 	free(tids);
370 	*sizep = size;
371 }
372 
373 /*
374  * Emit one note section to sbuf.
375  */
376 static void
377 elf_putnote(int type, notefunc_t notefunc, void *arg, struct sbuf *sb)
378 {
379 	Elf_Note note;
380 	size_t descsz;
381 	ssize_t old_len;
382 	void *desc;
383 
384 	desc = notefunc(arg, &descsz);
385 	note.n_namesz = 8; /* strlen("FreeBSD") + 1 */
386 	note.n_descsz = descsz;
387 	note.n_type = type;
388 
389 	sbuf_bcat(sb, &note, sizeof(note));
390 	sbuf_start_section(sb, &old_len);
391 	sbuf_bcat(sb, "FreeBSD", note.n_namesz);
392 	sbuf_end_section(sb, old_len, sizeof(Elf32_Size), 0);
393 	if (descsz == 0)
394 		return;
395 	sbuf_start_section(sb, &old_len);
396 	sbuf_bcat(sb, desc, descsz);
397 	sbuf_end_section(sb, old_len, sizeof(Elf32_Size), 0);
398 	free(desc);
399 }
400 
401 /*
402  * Generate the ELF coredump header.
403  */
404 static void
405 elf_puthdr(pid_t pid, vm_map_entry_t map, void *hdr, size_t hdrsize,
406     size_t notesz, size_t segoff, int numsegs)
407 {
408 	Elf_Ehdr *ehdr;
409 	Elf_Phdr *phdr;
410 	struct phdr_closure phc;
411 
412 	ehdr = (Elf_Ehdr *)hdr;
413 	phdr = (Elf_Phdr *)((char *)hdr + sizeof(Elf_Ehdr));
414 
415 	ehdr->e_ident[EI_MAG0] = ELFMAG0;
416 	ehdr->e_ident[EI_MAG1] = ELFMAG1;
417 	ehdr->e_ident[EI_MAG2] = ELFMAG2;
418 	ehdr->e_ident[EI_MAG3] = ELFMAG3;
419 	ehdr->e_ident[EI_CLASS] = ELF_CLASS;
420 	ehdr->e_ident[EI_DATA] = ELF_DATA;
421 	ehdr->e_ident[EI_VERSION] = EV_CURRENT;
422 	ehdr->e_ident[EI_OSABI] = ELFOSABI_FREEBSD;
423 	ehdr->e_ident[EI_ABIVERSION] = 0;
424 	ehdr->e_ident[EI_PAD] = 0;
425 	ehdr->e_type = ET_CORE;
426 	ehdr->e_machine = ELF_ARCH;
427 	ehdr->e_version = EV_CURRENT;
428 	ehdr->e_entry = 0;
429 	ehdr->e_phoff = sizeof(Elf_Ehdr);
430 	ehdr->e_flags = 0;
431 	ehdr->e_ehsize = sizeof(Elf_Ehdr);
432 	ehdr->e_phentsize = sizeof(Elf_Phdr);
433 	ehdr->e_phnum = numsegs + 1;
434 	ehdr->e_shentsize = sizeof(Elf_Shdr);
435 	ehdr->e_shnum = 0;
436 	ehdr->e_shstrndx = SHN_UNDEF;
437 
438 	/*
439 	 * Fill in the program header entries.
440 	 */
441 
442 	/* The note segement. */
443 	phdr->p_type = PT_NOTE;
444 	phdr->p_offset = hdrsize;
445 	phdr->p_vaddr = 0;
446 	phdr->p_paddr = 0;
447 	phdr->p_filesz = notesz;
448 	phdr->p_memsz = 0;
449 	phdr->p_flags = PF_R;
450 	phdr->p_align = sizeof(Elf32_Size);
451 	phdr++;
452 
453 	/* All the writable segments from the program. */
454 	phc.phdr = phdr;
455 	phc.offset = segoff;
456 	each_writable_segment(map, cb_put_phdr, &phc);
457 }
458 
459 /*
460  * Free the memory map.
461  */
462 static void
463 freemap(vm_map_entry_t map)
464 {
465 
466 	while (map != NULL) {
467 		vm_map_entry_t next = map->next;
468 		free(map);
469 		map = next;
470 	}
471 }
472 
473 /*
474  * Read the process's memory map using kinfo_getvmmap(), and return a list of
475  * VM map entries.  Only the non-device read/writable segments are
476  * returned.  The map entries in the list aren't fully filled in; only
477  * the items we need are present.
478  */
479 static vm_map_entry_t
480 readmap(pid_t pid)
481 {
482 	vm_map_entry_t ent, *linkp, map;
483 	struct kinfo_vmentry *vmentl, *kve;
484 	int i, nitems;
485 
486 	vmentl = kinfo_getvmmap(pid, &nitems);
487 	if (vmentl == NULL)
488 		err(1, "cannot retrieve mappings for %u process", pid);
489 
490 	map = NULL;
491 	linkp = &map;
492 	for (i = 0; i < nitems; i++) {
493 		kve = &vmentl[i];
494 
495 		/*
496 		 * Ignore 'malformed' segments or ones representing memory
497 		 * mapping with MAP_NOCORE on.
498 		 * If the 'full' support is disabled, just dump the most
499 		 * meaningful data segments.
500 		 */
501 		if ((kve->kve_protection & KVME_PROT_READ) == 0 ||
502 		    (kve->kve_flags & KVME_FLAG_NOCOREDUMP) != 0 ||
503 		    kve->kve_type == KVME_TYPE_DEAD ||
504 		    kve->kve_type == KVME_TYPE_UNKNOWN ||
505 		    ((pflags & PFLAGS_FULL) == 0 &&
506 		    kve->kve_type != KVME_TYPE_DEFAULT &&
507 		    kve->kve_type != KVME_TYPE_VNODE &&
508 		    kve->kve_type != KVME_TYPE_SWAP))
509 			continue;
510 
511 		ent = calloc(1, sizeof(*ent));
512 		if (ent == NULL)
513 			errx(1, "out of memory");
514 		ent->start = (vm_offset_t)kve->kve_start;
515 		ent->end = (vm_offset_t)kve->kve_end;
516 		ent->protection = VM_PROT_READ | VM_PROT_WRITE;
517 		if ((kve->kve_protection & KVME_PROT_EXEC) != 0)
518 			ent->protection |= VM_PROT_EXECUTE;
519 
520 		*linkp = ent;
521 		linkp = &ent->next;
522 	}
523 	free(vmentl);
524 	return (map);
525 }
526 
527 /*
528  * Miscellaneous note out functions.
529  */
530 
531 static void *
532 elf_note_prpsinfo(void *arg, size_t *sizep)
533 {
534 	pid_t pid;
535 	elfcore_prpsinfo_t *psinfo;
536 	struct kinfo_proc kip;
537 	size_t len;
538 	int name[4];
539 
540 	pid = *(pid_t *)arg;
541 	psinfo = calloc(1, sizeof(*psinfo));
542 	if (psinfo == NULL)
543 		errx(1, "out of memory");
544 	psinfo->pr_version = PRPSINFO_VERSION;
545 	psinfo->pr_psinfosz = sizeof(*psinfo);
546 
547 	name[0] = CTL_KERN;
548 	name[1] = KERN_PROC;
549 	name[2] = KERN_PROC_PID;
550 	name[3] = pid;
551 	len = sizeof(kip);
552 	if (sysctl(name, 4, &kip, &len, NULL, 0) == -1)
553 		err(1, "kern.proc.pid.%u", pid);
554 	if (kip.ki_pid != pid)
555 		err(1, "kern.proc.pid.%u", pid);
556 	strncpy(psinfo->pr_fname, kip.ki_comm, MAXCOMLEN);
557 	strncpy(psinfo->pr_psargs, psinfo->pr_fname, PRARGSZ);
558 
559 	*sizep = sizeof(*psinfo);
560 	return (psinfo);
561 }
562 
563 static void *
564 elf_note_prstatus(void *arg, size_t *sizep)
565 {
566 	lwpid_t tid;
567 	elfcore_prstatus_t *status;
568 	struct reg greg;
569 
570 	tid = *(lwpid_t *)arg;
571 	status = calloc(1, sizeof(*status));
572 	if (status == NULL)
573 		errx(1, "out of memory");
574 	status->pr_version = PRSTATUS_VERSION;
575 	status->pr_statussz = sizeof(*status);
576 	status->pr_gregsetsz = sizeof(elfcore_gregset_t);
577 	status->pr_fpregsetsz = sizeof(elfcore_fpregset_t);
578 	status->pr_osreldate = __FreeBSD_version;
579 	status->pr_pid = tid;
580 	ptrace(PT_GETREGS, tid, (void *)&greg, 0);
581 	elf_convert_gregset(&status->pr_reg, &greg);
582 
583 	*sizep = sizeof(*status);
584 	return (status);
585 }
586 
587 static void *
588 elf_note_fpregset(void *arg, size_t *sizep)
589 {
590 	lwpid_t tid;
591 	elfcore_fpregset_t *fpregset;
592 	fpregset_t fpreg;
593 
594 	tid = *(lwpid_t *)arg;
595 	fpregset = calloc(1, sizeof(*fpregset));
596 	if (fpregset == NULL)
597 		errx(1, "out of memory");
598 	ptrace(PT_GETFPREGS, tid, (void *)&fpreg, 0);
599 	elf_convert_fpregset(fpregset, &fpreg);
600 
601 	*sizep = sizeof(*fpregset);
602 	return (fpregset);
603 }
604 
605 static void *
606 elf_note_thrmisc(void *arg, size_t *sizep)
607 {
608 	lwpid_t tid;
609 	struct ptrace_lwpinfo lwpinfo;
610 	thrmisc_t *thrmisc;
611 
612 	tid = *(lwpid_t *)arg;
613 	thrmisc = calloc(1, sizeof(*thrmisc));
614 	if (thrmisc == NULL)
615 		errx(1, "out of memory");
616 	ptrace(PT_LWPINFO, tid, (void *)&lwpinfo,
617 	    sizeof(lwpinfo));
618 	memset(&thrmisc->_pad, 0, sizeof(thrmisc->_pad));
619 	strcpy(thrmisc->pr_tname, lwpinfo.pl_tdname);
620 
621 	*sizep = sizeof(*thrmisc);
622 	return (thrmisc);
623 }
624 
625 #if defined(__i386__) || defined(__amd64__)
626 static void *
627 elf_note_x86_xstate(void *arg, size_t *sizep)
628 {
629 	lwpid_t tid;
630 	char *xstate;
631 	static bool xsave_checked = false;
632 	static struct ptrace_xstate_info info;
633 
634 	tid = *(lwpid_t *)arg;
635 	if (!xsave_checked) {
636 		if (ptrace(PT_GETXSTATE_INFO, tid, (void *)&info,
637 		    sizeof(info)) != 0)
638 			info.xsave_len = 0;
639 		xsave_checked = true;
640 	}
641 	if (info.xsave_len == 0) {
642 		*sizep = 0;
643 		return (NULL);
644 	}
645 	xstate = calloc(1, info.xsave_len);
646 	ptrace(PT_GETXSTATE, tid, xstate, 0);
647 	*(uint64_t *)(xstate + X86_XSTATE_XCR0_OFFSET) = info.xsave_mask;
648 	*sizep = info.xsave_len;
649 	return (xstate);
650 }
651 #endif
652 
653 static void *
654 procstat_sysctl(void *arg, int what, size_t structsz, size_t *sizep)
655 {
656 	size_t len;
657 	pid_t pid;
658 	int name[4], structsize;
659 	void *buf, *p;
660 
661 	pid = *(pid_t *)arg;
662 	structsize = structsz;
663 	name[0] = CTL_KERN;
664 	name[1] = KERN_PROC;
665 	name[2] = what;
666 	name[3] = pid;
667 	len = 0;
668 	if (sysctl(name, 4, NULL, &len, NULL, 0) == -1)
669 		err(1, "kern.proc.%d.%u", what, pid);
670 	buf = calloc(1, sizeof(structsize) + len * 4 / 3);
671 	if (buf == NULL)
672 		errx(1, "out of memory");
673 	bcopy(&structsize, buf, sizeof(structsize));
674 	p = (char *)buf + sizeof(structsize);
675 	if (sysctl(name, 4, p, &len, NULL, 0) == -1)
676 		err(1, "kern.proc.%d.%u", what, pid);
677 
678 	*sizep = sizeof(structsize) + len;
679 	return (buf);
680 }
681 
682 static void *
683 elf_note_procstat_proc(void *arg, size_t *sizep)
684 {
685 
686 	return (procstat_sysctl(arg, KERN_PROC_PID | KERN_PROC_INC_THREAD,
687 	    sizeof(struct kinfo_proc), sizep));
688 }
689 
690 static void *
691 elf_note_procstat_files(void *arg, size_t *sizep)
692 {
693 
694 	return (procstat_sysctl(arg, KERN_PROC_FILEDESC,
695 	    sizeof(struct kinfo_file), sizep));
696 }
697 
698 static void *
699 elf_note_procstat_vmmap(void *arg, size_t *sizep)
700 {
701 
702 	return (procstat_sysctl(arg, KERN_PROC_VMMAP,
703 	    sizeof(struct kinfo_vmentry), sizep));
704 }
705 
706 static void *
707 elf_note_procstat_groups(void *arg, size_t *sizep)
708 {
709 
710 	return (procstat_sysctl(arg, KERN_PROC_GROUPS, sizeof(gid_t), sizep));
711 }
712 
713 static void *
714 elf_note_procstat_umask(void *arg, size_t *sizep)
715 {
716 
717 	return (procstat_sysctl(arg, KERN_PROC_UMASK, sizeof(u_short), sizep));
718 }
719 
720 static void *
721 elf_note_procstat_osrel(void *arg, size_t *sizep)
722 {
723 
724 	return (procstat_sysctl(arg, KERN_PROC_OSREL, sizeof(int), sizep));
725 }
726 
727 static void *
728 elf_note_procstat_psstrings(void *arg, size_t *sizep)
729 {
730 
731 	return (procstat_sysctl(arg, KERN_PROC_PS_STRINGS,
732 	    sizeof(vm_offset_t), sizep));
733 }
734 
735 static void *
736 elf_note_procstat_auxv(void *arg, size_t *sizep)
737 {
738 
739 	return (procstat_sysctl(arg, KERN_PROC_AUXV,
740 	    sizeof(Elf_Auxinfo), sizep));
741 }
742 
743 static void *
744 elf_note_procstat_rlimit(void *arg, size_t *sizep)
745 {
746 	pid_t pid;
747 	size_t len;
748 	int i, name[5], structsize;
749 	void *buf, *p;
750 
751 	pid = *(pid_t *)arg;
752 	structsize = sizeof(struct rlimit) * RLIM_NLIMITS;
753 	buf = calloc(1, sizeof(structsize) + structsize);
754 	if (buf == NULL)
755 		errx(1, "out of memory");
756 	bcopy(&structsize, buf, sizeof(structsize));
757 	p = (char *)buf + sizeof(structsize);
758 	name[0] = CTL_KERN;
759 	name[1] = KERN_PROC;
760 	name[2] = KERN_PROC_RLIMIT;
761 	name[3] = pid;
762 	len = sizeof(struct rlimit);
763 	for (i = 0; i < RLIM_NLIMITS; i++) {
764 		name[4] = i;
765 		if (sysctl(name, 5, p, &len, NULL, 0) == -1)
766 			err(1, "kern.proc.rlimit.%u", pid);
767 		if (len != sizeof(struct rlimit))
768 			errx(1, "kern.proc.rlimit.%u: short read", pid);
769 		p += len;
770 	}
771 
772 	*sizep = sizeof(structsize) + structsize;
773 	return (buf);
774 }
775 
776 struct dumpers __elfN(dump) = { elf_ident, elf_coredump };
777 TEXT_SET(dumpset, __elfN(dump));
778