FreeBSD/Linux Kernel Cross Reference
sys/kern/imgact_elf.c
1 /*-
2 * Copyright (c) 2000 David O'Brien
3 * Copyright (c) 1995-1996 Søren Schmidt
4 * Copyright (c) 1996 Peter Wemm
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer
12 * in this position and unchanged.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. The name of the author may not be used to endorse or promote products
17 * derived from this software without specific prior written permission
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD: releng/9.0/sys/kern/imgact_elf.c 223825 2011-07-06 20:06:44Z trasz $");
33
34 #include "opt_capsicum.h"
35 #include "opt_compat.h"
36 #include "opt_core.h"
37
38 #include <sys/param.h>
39 #include <sys/capability.h>
40 #include <sys/exec.h>
41 #include <sys/fcntl.h>
42 #include <sys/imgact.h>
43 #include <sys/imgact_elf.h>
44 #include <sys/kernel.h>
45 #include <sys/lock.h>
46 #include <sys/malloc.h>
47 #include <sys/mount.h>
48 #include <sys/mutex.h>
49 #include <sys/mman.h>
50 #include <sys/namei.h>
51 #include <sys/pioctl.h>
52 #include <sys/proc.h>
53 #include <sys/procfs.h>
54 #include <sys/racct.h>
55 #include <sys/resourcevar.h>
56 #include <sys/sf_buf.h>
57 #include <sys/smp.h>
58 #include <sys/systm.h>
59 #include <sys/signalvar.h>
60 #include <sys/stat.h>
61 #include <sys/sx.h>
62 #include <sys/syscall.h>
63 #include <sys/sysctl.h>
64 #include <sys/sysent.h>
65 #include <sys/vnode.h>
66 #include <sys/syslog.h>
67 #include <sys/eventhandler.h>
68
69 #include <net/zlib.h>
70
71 #include <vm/vm.h>
72 #include <vm/vm_kern.h>
73 #include <vm/vm_param.h>
74 #include <vm/pmap.h>
75 #include <vm/vm_map.h>
76 #include <vm/vm_object.h>
77 #include <vm/vm_extern.h>
78
79 #include <machine/elf.h>
80 #include <machine/md_var.h>
81
82 #define OLD_EI_BRAND 8
83
84 static int __elfN(check_header)(const Elf_Ehdr *hdr);
85 static Elf_Brandinfo *__elfN(get_brandinfo)(struct image_params *imgp,
86 const char *interp, int32_t *osrel);
87 static int __elfN(load_file)(struct proc *p, const char *file, u_long *addr,
88 u_long *entry, size_t pagesize);
89 static int __elfN(load_section)(struct vmspace *vmspace, vm_object_t object,
90 vm_offset_t offset, caddr_t vmaddr, size_t memsz, size_t filsz,
91 vm_prot_t prot, size_t pagesize);
92 static int __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp);
93 static boolean_t __elfN(freebsd_trans_osrel)(const Elf_Note *note,
94 int32_t *osrel);
95 static boolean_t kfreebsd_trans_osrel(const Elf_Note *note, int32_t *osrel);
96 static boolean_t __elfN(check_note)(struct image_params *imgp,
97 Elf_Brandnote *checknote, int32_t *osrel);
98 static vm_prot_t __elfN(trans_prot)(Elf_Word);
99 static Elf_Word __elfN(untrans_prot)(vm_prot_t);
100
101 SYSCTL_NODE(_kern, OID_AUTO, __CONCAT(elf, __ELF_WORD_SIZE), CTLFLAG_RW, 0,
102 "");
103
104 #ifdef COMPRESS_USER_CORES
105 static int compress_core(gzFile, char *, char *, unsigned int,
106 struct thread * td);
107 #define CORE_BUF_SIZE (16 * 1024)
108 #endif
109
110 int __elfN(fallback_brand) = -1;
111 SYSCTL_INT(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO,
112 fallback_brand, CTLFLAG_RW, &__elfN(fallback_brand), 0,
113 __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) " brand of last resort");
114 TUNABLE_INT("kern.elf" __XSTRING(__ELF_WORD_SIZE) ".fallback_brand",
115 &__elfN(fallback_brand));
116
117 static int elf_legacy_coredump = 0;
118 SYSCTL_INT(_debug, OID_AUTO, __elfN(legacy_coredump), CTLFLAG_RW,
119 &elf_legacy_coredump, 0, "");
120
121 static int __elfN(nxstack) = 0;
122 SYSCTL_INT(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO,
123 nxstack, CTLFLAG_RW, &__elfN(nxstack), 0,
124 __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) ": enable non-executable stack");
125
126 static Elf_Brandinfo *elf_brand_list[MAX_BRANDS];
127
128 #define trunc_page_ps(va, ps) ((va) & ~(ps - 1))
129 #define round_page_ps(va, ps) (((va) + (ps - 1)) & ~(ps - 1))
130 #define aligned(a, t) (trunc_page_ps((u_long)(a), sizeof(t)) == (u_long)(a))
131
132 static const char FREEBSD_ABI_VENDOR[] = "FreeBSD";
133
134 Elf_Brandnote __elfN(freebsd_brandnote) = {
135 .hdr.n_namesz = sizeof(FREEBSD_ABI_VENDOR),
136 .hdr.n_descsz = sizeof(int32_t),
137 .hdr.n_type = 1,
138 .vendor = FREEBSD_ABI_VENDOR,
139 .flags = BN_TRANSLATE_OSREL,
140 .trans_osrel = __elfN(freebsd_trans_osrel)
141 };
142
143 static boolean_t
144 __elfN(freebsd_trans_osrel)(const Elf_Note *note, int32_t *osrel)
145 {
146 uintptr_t p;
147
148 p = (uintptr_t)(note + 1);
149 p += roundup2(note->n_namesz, sizeof(Elf32_Addr));
150 *osrel = *(const int32_t *)(p);
151
152 return (TRUE);
153 }
154
155 static const char GNU_ABI_VENDOR[] = "GNU";
156 static int GNU_KFREEBSD_ABI_DESC = 3;
157
158 Elf_Brandnote __elfN(kfreebsd_brandnote) = {
159 .hdr.n_namesz = sizeof(GNU_ABI_VENDOR),
160 .hdr.n_descsz = 16, /* XXX at least 16 */
161 .hdr.n_type = 1,
162 .vendor = GNU_ABI_VENDOR,
163 .flags = BN_TRANSLATE_OSREL,
164 .trans_osrel = kfreebsd_trans_osrel
165 };
166
167 static boolean_t
168 kfreebsd_trans_osrel(const Elf_Note *note, int32_t *osrel)
169 {
170 const Elf32_Word *desc;
171 uintptr_t p;
172
173 p = (uintptr_t)(note + 1);
174 p += roundup2(note->n_namesz, sizeof(Elf32_Addr));
175
176 desc = (const Elf32_Word *)p;
177 if (desc[0] != GNU_KFREEBSD_ABI_DESC)
178 return (FALSE);
179
180 /*
181 * Debian GNU/kFreeBSD embed the earliest compatible kernel version
182 * (__FreeBSD_version: <major><two digit minor>Rxx) in the LSB way.
183 */
184 *osrel = desc[1] * 100000 + desc[2] * 1000 + desc[3];
185
186 return (TRUE);
187 }
188
189 int
190 __elfN(insert_brand_entry)(Elf_Brandinfo *entry)
191 {
192 int i;
193
194 for (i = 0; i < MAX_BRANDS; i++) {
195 if (elf_brand_list[i] == NULL) {
196 elf_brand_list[i] = entry;
197 break;
198 }
199 }
200 if (i == MAX_BRANDS) {
201 printf("WARNING: %s: could not insert brandinfo entry: %p\n",
202 __func__, entry);
203 return (-1);
204 }
205 return (0);
206 }
207
208 int
209 __elfN(remove_brand_entry)(Elf_Brandinfo *entry)
210 {
211 int i;
212
213 for (i = 0; i < MAX_BRANDS; i++) {
214 if (elf_brand_list[i] == entry) {
215 elf_brand_list[i] = NULL;
216 break;
217 }
218 }
219 if (i == MAX_BRANDS)
220 return (-1);
221 return (0);
222 }
223
224 int
225 __elfN(brand_inuse)(Elf_Brandinfo *entry)
226 {
227 struct proc *p;
228 int rval = FALSE;
229
230 sx_slock(&allproc_lock);
231 FOREACH_PROC_IN_SYSTEM(p) {
232 if (p->p_sysent == entry->sysvec) {
233 rval = TRUE;
234 break;
235 }
236 }
237 sx_sunlock(&allproc_lock);
238
239 return (rval);
240 }
241
242 static Elf_Brandinfo *
243 __elfN(get_brandinfo)(struct image_params *imgp, const char *interp,
244 int32_t *osrel)
245 {
246 const Elf_Ehdr *hdr = (const Elf_Ehdr *)imgp->image_header;
247 Elf_Brandinfo *bi;
248 boolean_t ret;
249 int i;
250
251 /*
252 * We support four types of branding -- (1) the ELF EI_OSABI field
253 * that SCO added to the ELF spec, (2) FreeBSD 3.x's traditional string
254 * branding w/in the ELF header, (3) path of the `interp_path'
255 * field, and (4) the ".note.ABI-tag" ELF section.
256 */
257
258 /* Look for an ".note.ABI-tag" ELF section */
259 for (i = 0; i < MAX_BRANDS; i++) {
260 bi = elf_brand_list[i];
261 if (bi == NULL)
262 continue;
263 if (hdr->e_machine == bi->machine && (bi->flags &
264 (BI_BRAND_NOTE|BI_BRAND_NOTE_MANDATORY)) != 0) {
265 ret = __elfN(check_note)(imgp, bi->brand_note, osrel);
266 if (ret)
267 return (bi);
268 }
269 }
270
271 /* If the executable has a brand, search for it in the brand list. */
272 for (i = 0; i < MAX_BRANDS; i++) {
273 bi = elf_brand_list[i];
274 if (bi == NULL || bi->flags & BI_BRAND_NOTE_MANDATORY)
275 continue;
276 if (hdr->e_machine == bi->machine &&
277 (hdr->e_ident[EI_OSABI] == bi->brand ||
278 strncmp((const char *)&hdr->e_ident[OLD_EI_BRAND],
279 bi->compat_3_brand, strlen(bi->compat_3_brand)) == 0))
280 return (bi);
281 }
282
283 /* Lacking a known brand, search for a recognized interpreter. */
284 if (interp != NULL) {
285 for (i = 0; i < MAX_BRANDS; i++) {
286 bi = elf_brand_list[i];
287 if (bi == NULL || bi->flags & BI_BRAND_NOTE_MANDATORY)
288 continue;
289 if (hdr->e_machine == bi->machine &&
290 strcmp(interp, bi->interp_path) == 0)
291 return (bi);
292 }
293 }
294
295 /* Lacking a recognized interpreter, try the default brand */
296 for (i = 0; i < MAX_BRANDS; i++) {
297 bi = elf_brand_list[i];
298 if (bi == NULL || bi->flags & BI_BRAND_NOTE_MANDATORY)
299 continue;
300 if (hdr->e_machine == bi->machine &&
301 __elfN(fallback_brand) == bi->brand)
302 return (bi);
303 }
304 return (NULL);
305 }
306
307 static int
308 __elfN(check_header)(const Elf_Ehdr *hdr)
309 {
310 Elf_Brandinfo *bi;
311 int i;
312
313 if (!IS_ELF(*hdr) ||
314 hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS ||
315 hdr->e_ident[EI_DATA] != ELF_TARG_DATA ||
316 hdr->e_ident[EI_VERSION] != EV_CURRENT ||
317 hdr->e_phentsize != sizeof(Elf_Phdr) ||
318 hdr->e_version != ELF_TARG_VER)
319 return (ENOEXEC);
320
321 /*
322 * Make sure we have at least one brand for this machine.
323 */
324
325 for (i = 0; i < MAX_BRANDS; i++) {
326 bi = elf_brand_list[i];
327 if (bi != NULL && bi->machine == hdr->e_machine)
328 break;
329 }
330 if (i == MAX_BRANDS)
331 return (ENOEXEC);
332
333 return (0);
334 }
335
336 static int
337 __elfN(map_partial)(vm_map_t map, vm_object_t object, vm_ooffset_t offset,
338 vm_offset_t start, vm_offset_t end, vm_prot_t prot)
339 {
340 struct sf_buf *sf;
341 int error;
342 vm_offset_t off;
343
344 /*
345 * Create the page if it doesn't exist yet. Ignore errors.
346 */
347 vm_map_lock(map);
348 vm_map_insert(map, NULL, 0, trunc_page(start), round_page(end),
349 VM_PROT_ALL, VM_PROT_ALL, 0);
350 vm_map_unlock(map);
351
352 /*
353 * Find the page from the underlying object.
354 */
355 if (object) {
356 sf = vm_imgact_map_page(object, offset);
357 if (sf == NULL)
358 return (KERN_FAILURE);
359 off = offset - trunc_page(offset);
360 error = copyout((caddr_t)sf_buf_kva(sf) + off, (caddr_t)start,
361 end - start);
362 vm_imgact_unmap_page(sf);
363 if (error) {
364 return (KERN_FAILURE);
365 }
366 }
367
368 return (KERN_SUCCESS);
369 }
370
371 static int
372 __elfN(map_insert)(vm_map_t map, vm_object_t object, vm_ooffset_t offset,
373 vm_offset_t start, vm_offset_t end, vm_prot_t prot, int cow)
374 {
375 struct sf_buf *sf;
376 vm_offset_t off;
377 vm_size_t sz;
378 int error, rv;
379
380 if (start != trunc_page(start)) {
381 rv = __elfN(map_partial)(map, object, offset, start,
382 round_page(start), prot);
383 if (rv)
384 return (rv);
385 offset += round_page(start) - start;
386 start = round_page(start);
387 }
388 if (end != round_page(end)) {
389 rv = __elfN(map_partial)(map, object, offset +
390 trunc_page(end) - start, trunc_page(end), end, prot);
391 if (rv)
392 return (rv);
393 end = trunc_page(end);
394 }
395 if (end > start) {
396 if (offset & PAGE_MASK) {
397 /*
398 * The mapping is not page aligned. This means we have
399 * to copy the data. Sigh.
400 */
401 rv = vm_map_find(map, NULL, 0, &start, end - start,
402 FALSE, prot | VM_PROT_WRITE, VM_PROT_ALL, 0);
403 if (rv)
404 return (rv);
405 if (object == NULL)
406 return (KERN_SUCCESS);
407 for (; start < end; start += sz) {
408 sf = vm_imgact_map_page(object, offset);
409 if (sf == NULL)
410 return (KERN_FAILURE);
411 off = offset - trunc_page(offset);
412 sz = end - start;
413 if (sz > PAGE_SIZE - off)
414 sz = PAGE_SIZE - off;
415 error = copyout((caddr_t)sf_buf_kva(sf) + off,
416 (caddr_t)start, sz);
417 vm_imgact_unmap_page(sf);
418 if (error) {
419 return (KERN_FAILURE);
420 }
421 offset += sz;
422 }
423 rv = KERN_SUCCESS;
424 } else {
425 vm_object_reference(object);
426 vm_map_lock(map);
427 rv = vm_map_insert(map, object, offset, start, end,
428 prot, VM_PROT_ALL, cow);
429 vm_map_unlock(map);
430 if (rv != KERN_SUCCESS)
431 vm_object_deallocate(object);
432 }
433 return (rv);
434 } else {
435 return (KERN_SUCCESS);
436 }
437 }
438
439 static int
440 __elfN(load_section)(struct vmspace *vmspace,
441 vm_object_t object, vm_offset_t offset,
442 caddr_t vmaddr, size_t memsz, size_t filsz, vm_prot_t prot,
443 size_t pagesize)
444 {
445 struct sf_buf *sf;
446 size_t map_len;
447 vm_offset_t map_addr;
448 int error, rv, cow;
449 size_t copy_len;
450 vm_offset_t file_addr;
451
452 /*
453 * It's necessary to fail if the filsz + offset taken from the
454 * header is greater than the actual file pager object's size.
455 * If we were to allow this, then the vm_map_find() below would
456 * walk right off the end of the file object and into the ether.
457 *
458 * While I'm here, might as well check for something else that
459 * is invalid: filsz cannot be greater than memsz.
460 */
461 if ((off_t)filsz + offset > object->un_pager.vnp.vnp_size ||
462 filsz > memsz) {
463 uprintf("elf_load_section: truncated ELF file\n");
464 return (ENOEXEC);
465 }
466
467 map_addr = trunc_page_ps((vm_offset_t)vmaddr, pagesize);
468 file_addr = trunc_page_ps(offset, pagesize);
469
470 /*
471 * We have two choices. We can either clear the data in the last page
472 * of an oversized mapping, or we can start the anon mapping a page
473 * early and copy the initialized data into that first page. We
474 * choose the second..
475 */
476 if (memsz > filsz)
477 map_len = trunc_page_ps(offset + filsz, pagesize) - file_addr;
478 else
479 map_len = round_page_ps(offset + filsz, pagesize) - file_addr;
480
481 if (map_len != 0) {
482 /* cow flags: don't dump readonly sections in core */
483 cow = MAP_COPY_ON_WRITE | MAP_PREFAULT |
484 (prot & VM_PROT_WRITE ? 0 : MAP_DISABLE_COREDUMP);
485
486 rv = __elfN(map_insert)(&vmspace->vm_map,
487 object,
488 file_addr, /* file offset */
489 map_addr, /* virtual start */
490 map_addr + map_len,/* virtual end */
491 prot,
492 cow);
493 if (rv != KERN_SUCCESS)
494 return (EINVAL);
495
496 /* we can stop now if we've covered it all */
497 if (memsz == filsz) {
498 return (0);
499 }
500 }
501
502
503 /*
504 * We have to get the remaining bit of the file into the first part
505 * of the oversized map segment. This is normally because the .data
506 * segment in the file is extended to provide bss. It's a neat idea
507 * to try and save a page, but it's a pain in the behind to implement.
508 */
509 copy_len = (offset + filsz) - trunc_page_ps(offset + filsz, pagesize);
510 map_addr = trunc_page_ps((vm_offset_t)vmaddr + filsz, pagesize);
511 map_len = round_page_ps((vm_offset_t)vmaddr + memsz, pagesize) -
512 map_addr;
513
514 /* This had damn well better be true! */
515 if (map_len != 0) {
516 rv = __elfN(map_insert)(&vmspace->vm_map, NULL, 0, map_addr,
517 map_addr + map_len, VM_PROT_ALL, 0);
518 if (rv != KERN_SUCCESS) {
519 return (EINVAL);
520 }
521 }
522
523 if (copy_len != 0) {
524 vm_offset_t off;
525
526 sf = vm_imgact_map_page(object, offset + filsz);
527 if (sf == NULL)
528 return (EIO);
529
530 /* send the page fragment to user space */
531 off = trunc_page_ps(offset + filsz, pagesize) -
532 trunc_page(offset + filsz);
533 error = copyout((caddr_t)sf_buf_kva(sf) + off,
534 (caddr_t)map_addr, copy_len);
535 vm_imgact_unmap_page(sf);
536 if (error) {
537 return (error);
538 }
539 }
540
541 /*
542 * set it to the specified protection.
543 * XXX had better undo the damage from pasting over the cracks here!
544 */
545 vm_map_protect(&vmspace->vm_map, trunc_page(map_addr),
546 round_page(map_addr + map_len), prot, FALSE);
547
548 return (0);
549 }
550
551 /*
552 * Load the file "file" into memory. It may be either a shared object
553 * or an executable.
554 *
555 * The "addr" reference parameter is in/out. On entry, it specifies
556 * the address where a shared object should be loaded. If the file is
557 * an executable, this value is ignored. On exit, "addr" specifies
558 * where the file was actually loaded.
559 *
560 * The "entry" reference parameter is out only. On exit, it specifies
561 * the entry point for the loaded file.
562 */
563 static int
564 __elfN(load_file)(struct proc *p, const char *file, u_long *addr,
565 u_long *entry, size_t pagesize)
566 {
567 struct {
568 struct nameidata nd;
569 struct vattr attr;
570 struct image_params image_params;
571 } *tempdata;
572 const Elf_Ehdr *hdr = NULL;
573 const Elf_Phdr *phdr = NULL;
574 struct nameidata *nd;
575 struct vmspace *vmspace = p->p_vmspace;
576 struct vattr *attr;
577 struct image_params *imgp;
578 vm_prot_t prot;
579 u_long rbase;
580 u_long base_addr = 0;
581 int vfslocked, error, i, numsegs;
582
583 #ifdef CAPABILITY_MODE
584 /*
585 * XXXJA: This check can go away once we are sufficiently confident
586 * that the checks in namei() are correct.
587 */
588 if (IN_CAPABILITY_MODE(curthread))
589 return (ECAPMODE);
590 #endif
591
592 tempdata = malloc(sizeof(*tempdata), M_TEMP, M_WAITOK);
593 nd = &tempdata->nd;
594 attr = &tempdata->attr;
595 imgp = &tempdata->image_params;
596
597 /*
598 * Initialize part of the common data
599 */
600 imgp->proc = p;
601 imgp->attr = attr;
602 imgp->firstpage = NULL;
603 imgp->image_header = NULL;
604 imgp->object = NULL;
605 imgp->execlabel = NULL;
606
607 NDINIT(nd, LOOKUP, MPSAFE|LOCKLEAF|FOLLOW, UIO_SYSSPACE, file,
608 curthread);
609 vfslocked = 0;
610 if ((error = namei(nd)) != 0) {
611 nd->ni_vp = NULL;
612 goto fail;
613 }
614 vfslocked = NDHASGIANT(nd);
615 NDFREE(nd, NDF_ONLY_PNBUF);
616 imgp->vp = nd->ni_vp;
617
618 /*
619 * Check permissions, modes, uid, etc on the file, and "open" it.
620 */
621 error = exec_check_permissions(imgp);
622 if (error)
623 goto fail;
624
625 error = exec_map_first_page(imgp);
626 if (error)
627 goto fail;
628
629 /*
630 * Also make certain that the interpreter stays the same, so set
631 * its VV_TEXT flag, too.
632 */
633 nd->ni_vp->v_vflag |= VV_TEXT;
634
635 imgp->object = nd->ni_vp->v_object;
636
637 hdr = (const Elf_Ehdr *)imgp->image_header;
638 if ((error = __elfN(check_header)(hdr)) != 0)
639 goto fail;
640 if (hdr->e_type == ET_DYN)
641 rbase = *addr;
642 else if (hdr->e_type == ET_EXEC)
643 rbase = 0;
644 else {
645 error = ENOEXEC;
646 goto fail;
647 }
648
649 /* Only support headers that fit within first page for now */
650 /* (multiplication of two Elf_Half fields will not overflow) */
651 if ((hdr->e_phoff > PAGE_SIZE) ||
652 (hdr->e_phentsize * hdr->e_phnum) > PAGE_SIZE - hdr->e_phoff) {
653 error = ENOEXEC;
654 goto fail;
655 }
656
657 phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff);
658 if (!aligned(phdr, Elf_Addr)) {
659 error = ENOEXEC;
660 goto fail;
661 }
662
663 for (i = 0, numsegs = 0; i < hdr->e_phnum; i++) {
664 if (phdr[i].p_type == PT_LOAD && phdr[i].p_memsz != 0) {
665 /* Loadable segment */
666 prot = __elfN(trans_prot)(phdr[i].p_flags);
667 if ((error = __elfN(load_section)(vmspace,
668 imgp->object, phdr[i].p_offset,
669 (caddr_t)(uintptr_t)phdr[i].p_vaddr + rbase,
670 phdr[i].p_memsz, phdr[i].p_filesz, prot,
671 pagesize)) != 0)
672 goto fail;
673 /*
674 * Establish the base address if this is the
675 * first segment.
676 */
677 if (numsegs == 0)
678 base_addr = trunc_page(phdr[i].p_vaddr +
679 rbase);
680 numsegs++;
681 }
682 }
683 *addr = base_addr;
684 *entry = (unsigned long)hdr->e_entry + rbase;
685
686 fail:
687 if (imgp->firstpage)
688 exec_unmap_first_page(imgp);
689
690 if (nd->ni_vp)
691 vput(nd->ni_vp);
692
693 VFS_UNLOCK_GIANT(vfslocked);
694 free(tempdata, M_TEMP);
695
696 return (error);
697 }
698
699 static int
700 __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp)
701 {
702 const Elf_Ehdr *hdr = (const Elf_Ehdr *)imgp->image_header;
703 const Elf_Phdr *phdr;
704 Elf_Auxargs *elf_auxargs;
705 struct vmspace *vmspace;
706 vm_prot_t prot;
707 u_long text_size = 0, data_size = 0, total_size = 0;
708 u_long text_addr = 0, data_addr = 0;
709 u_long seg_size, seg_addr;
710 u_long addr, baddr, et_dyn_addr, entry = 0, proghdr = 0;
711 int32_t osrel = 0;
712 int error = 0, i, n;
713 const char *interp = NULL, *newinterp = NULL;
714 Elf_Brandinfo *brand_info;
715 char *path;
716 struct sysentvec *sv;
717
718 /*
719 * Do we have a valid ELF header ?
720 *
721 * Only allow ET_EXEC & ET_DYN here, reject ET_DYN later
722 * if particular brand doesn't support it.
723 */
724 if (__elfN(check_header)(hdr) != 0 ||
725 (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN))
726 return (-1);
727
728 /*
729 * From here on down, we return an errno, not -1, as we've
730 * detected an ELF file.
731 */
732
733 if ((hdr->e_phoff > PAGE_SIZE) ||
734 (hdr->e_phoff + hdr->e_phentsize * hdr->e_phnum) > PAGE_SIZE) {
735 /* Only support headers in first page for now */
736 return (ENOEXEC);
737 }
738 phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff);
739 if (!aligned(phdr, Elf_Addr))
740 return (ENOEXEC);
741 n = 0;
742 baddr = 0;
743 for (i = 0; i < hdr->e_phnum; i++) {
744 switch (phdr[i].p_type) {
745 case PT_LOAD:
746 if (n == 0)
747 baddr = phdr[i].p_vaddr;
748 n++;
749 break;
750 case PT_INTERP:
751 /* Path to interpreter */
752 if (phdr[i].p_filesz > MAXPATHLEN ||
753 phdr[i].p_offset + phdr[i].p_filesz > PAGE_SIZE)
754 return (ENOEXEC);
755 interp = imgp->image_header + phdr[i].p_offset;
756 break;
757 case PT_GNU_STACK:
758 if (__elfN(nxstack))
759 imgp->stack_prot =
760 __elfN(trans_prot)(phdr[i].p_flags);
761 break;
762 }
763 }
764
765 brand_info = __elfN(get_brandinfo)(imgp, interp, &osrel);
766 if (brand_info == NULL) {
767 uprintf("ELF binary type \"%u\" not known.\n",
768 hdr->e_ident[EI_OSABI]);
769 return (ENOEXEC);
770 }
771 if (hdr->e_type == ET_DYN) {
772 if ((brand_info->flags & BI_CAN_EXEC_DYN) == 0)
773 return (ENOEXEC);
774 /*
775 * Honour the base load address from the dso if it is
776 * non-zero for some reason.
777 */
778 if (baddr == 0)
779 et_dyn_addr = ET_DYN_LOAD_ADDR;
780 else
781 et_dyn_addr = 0;
782 } else
783 et_dyn_addr = 0;
784 sv = brand_info->sysvec;
785 if (interp != NULL && brand_info->interp_newpath != NULL)
786 newinterp = brand_info->interp_newpath;
787
788 /*
789 * Avoid a possible deadlock if the current address space is destroyed
790 * and that address space maps the locked vnode. In the common case,
791 * the locked vnode's v_usecount is decremented but remains greater
792 * than zero. Consequently, the vnode lock is not needed by vrele().
793 * However, in cases where the vnode lock is external, such as nullfs,
794 * v_usecount may become zero.
795 */
796 VOP_UNLOCK(imgp->vp, 0);
797
798 error = exec_new_vmspace(imgp, sv);
799 imgp->proc->p_sysent = sv;
800
801 vn_lock(imgp->vp, LK_EXCLUSIVE | LK_RETRY);
802 if (error)
803 return (error);
804
805 vmspace = imgp->proc->p_vmspace;
806
807 for (i = 0; i < hdr->e_phnum; i++) {
808 switch (phdr[i].p_type) {
809 case PT_LOAD: /* Loadable segment */
810 if (phdr[i].p_memsz == 0)
811 break;
812 prot = __elfN(trans_prot)(phdr[i].p_flags);
813
814 #if defined(__ia64__) && __ELF_WORD_SIZE == 32 && defined(IA32_ME_HARDER)
815 /*
816 * Some x86 binaries assume read == executable,
817 * notably the M3 runtime and therefore cvsup
818 */
819 if (prot & VM_PROT_READ)
820 prot |= VM_PROT_EXECUTE;
821 #endif
822
823 if ((error = __elfN(load_section)(vmspace,
824 imgp->object, phdr[i].p_offset,
825 (caddr_t)(uintptr_t)phdr[i].p_vaddr + et_dyn_addr,
826 phdr[i].p_memsz, phdr[i].p_filesz, prot,
827 sv->sv_pagesize)) != 0)
828 return (error);
829
830 /*
831 * If this segment contains the program headers,
832 * remember their virtual address for the AT_PHDR
833 * aux entry. Static binaries don't usually include
834 * a PT_PHDR entry.
835 */
836 if (phdr[i].p_offset == 0 &&
837 hdr->e_phoff + hdr->e_phnum * hdr->e_phentsize
838 <= phdr[i].p_filesz)
839 proghdr = phdr[i].p_vaddr + hdr->e_phoff +
840 et_dyn_addr;
841
842 seg_addr = trunc_page(phdr[i].p_vaddr + et_dyn_addr);
843 seg_size = round_page(phdr[i].p_memsz +
844 phdr[i].p_vaddr + et_dyn_addr - seg_addr);
845
846 /*
847 * Make the largest executable segment the official
848 * text segment and all others data.
849 *
850 * Note that obreak() assumes that data_addr +
851 * data_size == end of data load area, and the ELF
852 * file format expects segments to be sorted by
853 * address. If multiple data segments exist, the
854 * last one will be used.
855 */
856
857 if (phdr[i].p_flags & PF_X && text_size < seg_size) {
858 text_size = seg_size;
859 text_addr = seg_addr;
860 } else {
861 data_size = seg_size;
862 data_addr = seg_addr;
863 }
864 total_size += seg_size;
865 break;
866 case PT_PHDR: /* Program header table info */
867 proghdr = phdr[i].p_vaddr + et_dyn_addr;
868 break;
869 default:
870 break;
871 }
872 }
873
874 if (data_addr == 0 && data_size == 0) {
875 data_addr = text_addr;
876 data_size = text_size;
877 }
878
879 entry = (u_long)hdr->e_entry + et_dyn_addr;
880
881 /*
882 * Check limits. It should be safe to check the
883 * limits after loading the segments since we do
884 * not actually fault in all the segments pages.
885 */
886 PROC_LOCK(imgp->proc);
887 if (data_size > lim_cur(imgp->proc, RLIMIT_DATA) ||
888 text_size > maxtsiz ||
889 total_size > lim_cur(imgp->proc, RLIMIT_VMEM) ||
890 racct_set(imgp->proc, RACCT_DATA, data_size) != 0 ||
891 racct_set(imgp->proc, RACCT_VMEM, total_size) != 0) {
892 PROC_UNLOCK(imgp->proc);
893 return (ENOMEM);
894 }
895
896 vmspace->vm_tsize = text_size >> PAGE_SHIFT;
897 vmspace->vm_taddr = (caddr_t)(uintptr_t)text_addr;
898 vmspace->vm_dsize = data_size >> PAGE_SHIFT;
899 vmspace->vm_daddr = (caddr_t)(uintptr_t)data_addr;
900
901 /*
902 * We load the dynamic linker where a userland call
903 * to mmap(0, ...) would put it. The rationale behind this
904 * calculation is that it leaves room for the heap to grow to
905 * its maximum allowed size.
906 */
907 addr = round_page((vm_offset_t)imgp->proc->p_vmspace->vm_daddr +
908 lim_max(imgp->proc, RLIMIT_DATA));
909 PROC_UNLOCK(imgp->proc);
910
911 imgp->entry_addr = entry;
912
913 if (interp != NULL) {
914 int have_interp = FALSE;
915 VOP_UNLOCK(imgp->vp, 0);
916 if (brand_info->emul_path != NULL &&
917 brand_info->emul_path[0] != '\0') {
918 path = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
919 snprintf(path, MAXPATHLEN, "%s%s",
920 brand_info->emul_path, interp);
921 error = __elfN(load_file)(imgp->proc, path, &addr,
922 &imgp->entry_addr, sv->sv_pagesize);
923 free(path, M_TEMP);
924 if (error == 0)
925 have_interp = TRUE;
926 }
927 if (!have_interp && newinterp != NULL) {
928 error = __elfN(load_file)(imgp->proc, newinterp, &addr,
929 &imgp->entry_addr, sv->sv_pagesize);
930 if (error == 0)
931 have_interp = TRUE;
932 }
933 if (!have_interp) {
934 error = __elfN(load_file)(imgp->proc, interp, &addr,
935 &imgp->entry_addr, sv->sv_pagesize);
936 }
937 vn_lock(imgp->vp, LK_EXCLUSIVE | LK_RETRY);
938 if (error != 0) {
939 uprintf("ELF interpreter %s not found\n", interp);
940 return (error);
941 }
942 } else
943 addr = et_dyn_addr;
944
945 /*
946 * Construct auxargs table (used by the fixup routine)
947 */
948 elf_auxargs = malloc(sizeof(Elf_Auxargs), M_TEMP, M_WAITOK);
949 elf_auxargs->execfd = -1;
950 elf_auxargs->phdr = proghdr;
951 elf_auxargs->phent = hdr->e_phentsize;
952 elf_auxargs->phnum = hdr->e_phnum;
953 elf_auxargs->pagesz = PAGE_SIZE;
954 elf_auxargs->base = addr;
955 elf_auxargs->flags = 0;
956 elf_auxargs->entry = entry;
957
958 imgp->auxargs = elf_auxargs;
959 imgp->interpreted = 0;
960 imgp->reloc_base = addr;
961 imgp->proc->p_osrel = osrel;
962
963 return (error);
964 }
965
966 #define suword __CONCAT(suword, __ELF_WORD_SIZE)
967
968 int
969 __elfN(freebsd_fixup)(register_t **stack_base, struct image_params *imgp)
970 {
971 Elf_Auxargs *args = (Elf_Auxargs *)imgp->auxargs;
972 Elf_Addr *base;
973 Elf_Addr *pos;
974
975 base = (Elf_Addr *)*stack_base;
976 pos = base + (imgp->args->argc + imgp->args->envc + 2);
977
978 if (args->execfd != -1)
979 AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd);
980 AUXARGS_ENTRY(pos, AT_PHDR, args->phdr);
981 AUXARGS_ENTRY(pos, AT_PHENT, args->phent);
982 AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum);
983 AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz);
984 AUXARGS_ENTRY(pos, AT_FLAGS, args->flags);
985 AUXARGS_ENTRY(pos, AT_ENTRY, args->entry);
986 AUXARGS_ENTRY(pos, AT_BASE, args->base);
987 if (imgp->execpathp != 0)
988 AUXARGS_ENTRY(pos, AT_EXECPATH, imgp->execpathp);
989 AUXARGS_ENTRY(pos, AT_OSRELDATE, osreldate);
990 if (imgp->canary != 0) {
991 AUXARGS_ENTRY(pos, AT_CANARY, imgp->canary);
992 AUXARGS_ENTRY(pos, AT_CANARYLEN, imgp->canarylen);
993 }
994 AUXARGS_ENTRY(pos, AT_NCPUS, mp_ncpus);
995 if (imgp->pagesizes != 0) {
996 AUXARGS_ENTRY(pos, AT_PAGESIZES, imgp->pagesizes);
997 AUXARGS_ENTRY(pos, AT_PAGESIZESLEN, imgp->pagesizeslen);
998 }
999 AUXARGS_ENTRY(pos, AT_STACKPROT, imgp->sysent->sv_shared_page_obj
1000 != NULL && imgp->stack_prot != 0 ? imgp->stack_prot :
1001 imgp->sysent->sv_stackprot);
1002 AUXARGS_ENTRY(pos, AT_NULL, 0);
1003
1004 free(imgp->auxargs, M_TEMP);
1005 imgp->auxargs = NULL;
1006
1007 base--;
1008 suword(base, (long)imgp->args->argc);
1009 *stack_base = (register_t *)base;
1010 return (0);
1011 }
1012
1013 /*
1014 * Code for generating ELF core dumps.
1015 */
1016
1017 typedef void (*segment_callback)(vm_map_entry_t, void *);
1018
1019 /* Closure for cb_put_phdr(). */
1020 struct phdr_closure {
1021 Elf_Phdr *phdr; /* Program header to fill in */
1022 Elf_Off offset; /* Offset of segment in core file */
1023 };
1024
1025 /* Closure for cb_size_segment(). */
1026 struct sseg_closure {
1027 int count; /* Count of writable segments. */
1028 size_t size; /* Total size of all writable segments. */
1029 };
1030
1031 static void cb_put_phdr(vm_map_entry_t, void *);
1032 static void cb_size_segment(vm_map_entry_t, void *);
1033 static void each_writable_segment(struct thread *, segment_callback, void *);
1034 static int __elfN(corehdr)(struct thread *, struct vnode *, struct ucred *,
1035 int, void *, size_t, gzFile);
1036 static void __elfN(puthdr)(struct thread *, void *, size_t *, int);
1037 static void __elfN(putnote)(void *, size_t *, const char *, int,
1038 const void *, size_t);
1039
1040 #ifdef COMPRESS_USER_CORES
1041 extern int compress_user_cores;
1042 extern int compress_user_cores_gzlevel;
1043 #endif
1044
1045 static int
1046 core_output(struct vnode *vp, void *base, size_t len, off_t offset,
1047 struct ucred *active_cred, struct ucred *file_cred,
1048 struct thread *td, char *core_buf, gzFile gzfile) {
1049
1050 int error;
1051 if (gzfile) {
1052 #ifdef COMPRESS_USER_CORES
1053 error = compress_core(gzfile, base, core_buf, len, td);
1054 #else
1055 panic("shouldn't be here");
1056 #endif
1057 } else {
1058 error = vn_rdwr_inchunks(UIO_WRITE, vp, base, len, offset,
1059 UIO_USERSPACE, IO_UNIT | IO_DIRECT, active_cred, file_cred,
1060 NULL, td);
1061 }
1062 return (error);
1063 }
1064
1065 int
1066 __elfN(coredump)(struct thread *td, struct vnode *vp, off_t limit, int flags)
1067 {
1068 struct ucred *cred = td->td_ucred;
1069 int error = 0;
1070 struct sseg_closure seginfo;
1071 void *hdr;
1072 size_t hdrsize;
1073
1074 gzFile gzfile = Z_NULL;
1075 char *core_buf = NULL;
1076 #ifdef COMPRESS_USER_CORES
1077 char gzopen_flags[8];
1078 char *p;
1079 int doing_compress = flags & IMGACT_CORE_COMPRESS;
1080 #endif
1081
1082 hdr = NULL;
1083
1084 #ifdef COMPRESS_USER_CORES
1085 if (doing_compress) {
1086 p = gzopen_flags;
1087 *p++ = 'w';
1088 if (compress_user_cores_gzlevel >= 0 &&
1089 compress_user_cores_gzlevel <= 9)
1090 *p++ = '' + compress_user_cores_gzlevel;
1091 *p = 0;
1092 gzfile = gz_open("", gzopen_flags, vp);
1093 if (gzfile == Z_NULL) {
1094 error = EFAULT;
1095 goto done;
1096 }
1097 core_buf = malloc(CORE_BUF_SIZE, M_TEMP, M_WAITOK | M_ZERO);
1098 if (!core_buf) {
1099 error = ENOMEM;
1100 goto done;
1101 }
1102 }
1103 #endif
1104
1105 /* Size the program segments. */
1106 seginfo.count = 0;
1107 seginfo.size = 0;
1108 each_writable_segment(td, cb_size_segment, &seginfo);
1109
1110 /*
1111 * Calculate the size of the core file header area by making
1112 * a dry run of generating it. Nothing is written, but the
1113 * size is calculated.
1114 */
1115 hdrsize = 0;
1116 __elfN(puthdr)(td, (void *)NULL, &hdrsize, seginfo.count);
1117
1118 #ifdef RACCT
1119 PROC_LOCK(td->td_proc);
1120 error = racct_add(td->td_proc, RACCT_CORE, hdrsize + seginfo.size);
1121 PROC_UNLOCK(td->td_proc);
1122 if (error != 0) {
1123 error = EFAULT;
1124 goto done;
1125 }
1126 #endif
1127 if (hdrsize + seginfo.size >= limit) {
1128 error = EFAULT;
1129 goto done;
1130 }
1131
1132 /*
1133 * Allocate memory for building the header, fill it up,
1134 * and write it out.
1135 */
1136 hdr = malloc(hdrsize, M_TEMP, M_WAITOK);
1137 if (hdr == NULL) {
1138 error = EINVAL;
1139 goto done;
1140 }
1141 error = __elfN(corehdr)(td, vp, cred, seginfo.count, hdr, hdrsize,
1142 gzfile);
1143
1144 /* Write the contents of all of the writable segments. */
1145 if (error == 0) {
1146 Elf_Phdr *php;
1147 off_t offset;
1148 int i;
1149
1150 php = (Elf_Phdr *)((char *)hdr + sizeof(Elf_Ehdr)) + 1;
1151 offset = hdrsize;
1152 for (i = 0; i < seginfo.count; i++) {
1153 error = core_output(vp, (caddr_t)(uintptr_t)php->p_vaddr,
1154 php->p_filesz, offset, cred, NOCRED, curthread, core_buf, gzfile);
1155 if (error != 0)
1156 break;
1157 offset += php->p_filesz;
1158 php++;
1159 }
1160 }
1161 if (error) {
1162 log(LOG_WARNING,
1163 "Failed to write core file for process %s (error %d)\n",
1164 curproc->p_comm, error);
1165 }
1166
1167 done:
1168 #ifdef COMPRESS_USER_CORES
1169 if (core_buf)
1170 free(core_buf, M_TEMP);
1171 if (gzfile)
1172 gzclose(gzfile);
1173 #endif
1174
1175 free(hdr, M_TEMP);
1176
1177 return (error);
1178 }
1179
1180 /*
1181 * A callback for each_writable_segment() to write out the segment's
1182 * program header entry.
1183 */
1184 static void
1185 cb_put_phdr(entry, closure)
1186 vm_map_entry_t entry;
1187 void *closure;
1188 {
1189 struct phdr_closure *phc = (struct phdr_closure *)closure;
1190 Elf_Phdr *phdr = phc->phdr;
1191
1192 phc->offset = round_page(phc->offset);
1193
1194 phdr->p_type = PT_LOAD;
1195 phdr->p_offset = phc->offset;
1196 phdr->p_vaddr = entry->start;
1197 phdr->p_paddr = 0;
1198 phdr->p_filesz = phdr->p_memsz = entry->end - entry->start;
1199 phdr->p_align = PAGE_SIZE;
1200 phdr->p_flags = __elfN(untrans_prot)(entry->protection);
1201
1202 phc->offset += phdr->p_filesz;
1203 phc->phdr++;
1204 }
1205
1206 /*
1207 * A callback for each_writable_segment() to gather information about
1208 * the number of segments and their total size.
1209 */
1210 static void
1211 cb_size_segment(entry, closure)
1212 vm_map_entry_t entry;
1213 void *closure;
1214 {
1215 struct sseg_closure *ssc = (struct sseg_closure *)closure;
1216
1217 ssc->count++;
1218 ssc->size += entry->end - entry->start;
1219 }
1220
1221 /*
1222 * For each writable segment in the process's memory map, call the given
1223 * function with a pointer to the map entry and some arbitrary
1224 * caller-supplied data.
1225 */
1226 static void
1227 each_writable_segment(td, func, closure)
1228 struct thread *td;
1229 segment_callback func;
1230 void *closure;
1231 {
1232 struct proc *p = td->td_proc;
1233 vm_map_t map = &p->p_vmspace->vm_map;
1234 vm_map_entry_t entry;
1235 vm_object_t backing_object, object;
1236 boolean_t ignore_entry;
1237
1238 vm_map_lock_read(map);
1239 for (entry = map->header.next; entry != &map->header;
1240 entry = entry->next) {
1241 /*
1242 * Don't dump inaccessible mappings, deal with legacy
1243 * coredump mode.
1244 *
1245 * Note that read-only segments related to the elf binary
1246 * are marked MAP_ENTRY_NOCOREDUMP now so we no longer
1247 * need to arbitrarily ignore such segments.
1248 */
1249 if (elf_legacy_coredump) {
1250 if ((entry->protection & VM_PROT_RW) != VM_PROT_RW)
1251 continue;
1252 } else {
1253 if ((entry->protection & VM_PROT_ALL) == 0)
1254 continue;
1255 }
1256
1257 /*
1258 * Dont include memory segment in the coredump if
1259 * MAP_NOCORE is set in mmap(2) or MADV_NOCORE in
1260 * madvise(2). Do not dump submaps (i.e. parts of the
1261 * kernel map).
1262 */
1263 if (entry->eflags & (MAP_ENTRY_NOCOREDUMP|MAP_ENTRY_IS_SUB_MAP))
1264 continue;
1265
1266 if ((object = entry->object.vm_object) == NULL)
1267 continue;
1268
1269 /* Ignore memory-mapped devices and such things. */
1270 VM_OBJECT_LOCK(object);
1271 while ((backing_object = object->backing_object) != NULL) {
1272 VM_OBJECT_LOCK(backing_object);
1273 VM_OBJECT_UNLOCK(object);
1274 object = backing_object;
1275 }
1276 ignore_entry = object->type != OBJT_DEFAULT &&
1277 object->type != OBJT_SWAP && object->type != OBJT_VNODE;
1278 VM_OBJECT_UNLOCK(object);
1279 if (ignore_entry)
1280 continue;
1281
1282 (*func)(entry, closure);
1283 }
1284 vm_map_unlock_read(map);
1285 }
1286
1287 /*
1288 * Write the core file header to the file, including padding up to
1289 * the page boundary.
1290 */
1291 static int
1292 __elfN(corehdr)(td, vp, cred, numsegs, hdr, hdrsize, gzfile)
1293 struct thread *td;
1294 struct vnode *vp;
1295 struct ucred *cred;
1296 int numsegs;
1297 size_t hdrsize;
1298 void *hdr;
1299 gzFile gzfile;
1300 {
1301 size_t off;
1302
1303 /* Fill in the header. */
1304 bzero(hdr, hdrsize);
1305 off = 0;
1306 __elfN(puthdr)(td, hdr, &off, numsegs);
1307
1308 if (!gzfile) {
1309 /* Write it to the core file. */
1310 return (vn_rdwr_inchunks(UIO_WRITE, vp, hdr, hdrsize, (off_t)0,
1311 UIO_SYSSPACE, IO_UNIT | IO_DIRECT, cred, NOCRED, NULL,
1312 td));
1313 } else {
1314 #ifdef COMPRESS_USER_CORES
1315 if (gzwrite(gzfile, hdr, hdrsize) != hdrsize) {
1316 log(LOG_WARNING,
1317 "Failed to compress core file header for process"
1318 " %s.\n", curproc->p_comm);
1319 return (EFAULT);
1320 }
1321 else {
1322 return (0);
1323 }
1324 #else
1325 panic("shouldn't be here");
1326 #endif
1327 }
1328 }
1329
1330 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32
1331 #include <compat/freebsd32/freebsd32.h>
1332
1333 typedef struct prstatus32 elf_prstatus_t;
1334 typedef struct prpsinfo32 elf_prpsinfo_t;
1335 typedef struct fpreg32 elf_prfpregset_t;
1336 typedef struct fpreg32 elf_fpregset_t;
1337 typedef struct reg32 elf_gregset_t;
1338 typedef struct thrmisc32 elf_thrmisc_t;
1339 #else
1340 typedef prstatus_t elf_prstatus_t;
1341 typedef prpsinfo_t elf_prpsinfo_t;
1342 typedef prfpregset_t elf_prfpregset_t;
1343 typedef prfpregset_t elf_fpregset_t;
1344 typedef gregset_t elf_gregset_t;
1345 typedef thrmisc_t elf_thrmisc_t;
1346 #endif
1347
1348 static void
1349 __elfN(puthdr)(struct thread *td, void *dst, size_t *off, int numsegs)
1350 {
1351 struct {
1352 elf_prstatus_t status;
1353 elf_prfpregset_t fpregset;
1354 elf_prpsinfo_t psinfo;
1355 elf_thrmisc_t thrmisc;
1356 } *tempdata;
1357 elf_prstatus_t *status;
1358 elf_prfpregset_t *fpregset;
1359 elf_prpsinfo_t *psinfo;
1360 elf_thrmisc_t *thrmisc;
1361 struct proc *p;
1362 struct thread *thr;
1363 size_t ehoff, noteoff, notesz, phoff;
1364
1365 p = td->td_proc;
1366
1367 ehoff = *off;
1368 *off += sizeof(Elf_Ehdr);
1369
1370 phoff = *off;
1371 *off += (numsegs + 1) * sizeof(Elf_Phdr);
1372
1373 noteoff = *off;
1374 /*
1375 * Don't allocate space for the notes if we're just calculating
1376 * the size of the header. We also don't collect the data.
1377 */
1378 if (dst != NULL) {
1379 tempdata = malloc(sizeof(*tempdata), M_TEMP, M_ZERO|M_WAITOK);
1380 status = &tempdata->status;
1381 fpregset = &tempdata->fpregset;
1382 psinfo = &tempdata->psinfo;
1383 thrmisc = &tempdata->thrmisc;
1384 } else {
1385 tempdata = NULL;
1386 status = NULL;
1387 fpregset = NULL;
1388 psinfo = NULL;
1389 thrmisc = NULL;
1390 }
1391
1392 if (dst != NULL) {
1393 psinfo->pr_version = PRPSINFO_VERSION;
1394 psinfo->pr_psinfosz = sizeof(elf_prpsinfo_t);
1395 strlcpy(psinfo->pr_fname, p->p_comm, sizeof(psinfo->pr_fname));
1396 /*
1397 * XXX - We don't fill in the command line arguments properly
1398 * yet.
1399 */
1400 strlcpy(psinfo->pr_psargs, p->p_comm,
1401 sizeof(psinfo->pr_psargs));
1402 }
1403 __elfN(putnote)(dst, off, "FreeBSD", NT_PRPSINFO, psinfo,
1404 sizeof *psinfo);
1405
1406 /*
1407 * To have the debugger select the right thread (LWP) as the initial
1408 * thread, we dump the state of the thread passed to us in td first.
1409 * This is the thread that causes the core dump and thus likely to
1410 * be the right thread one wants to have selected in the debugger.
1411 */
1412 thr = td;
1413 while (thr != NULL) {
1414 if (dst != NULL) {
1415 status->pr_version = PRSTATUS_VERSION;
1416 status->pr_statussz = sizeof(elf_prstatus_t);
1417 status->pr_gregsetsz = sizeof(elf_gregset_t);
1418 status->pr_fpregsetsz = sizeof(elf_fpregset_t);
1419 status->pr_osreldate = osreldate;
1420 status->pr_cursig = p->p_sig;
1421 status->pr_pid = thr->td_tid;
1422 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32
1423 fill_regs32(thr, &status->pr_reg);
1424 fill_fpregs32(thr, fpregset);
1425 #else
1426 fill_regs(thr, &status->pr_reg);
1427 fill_fpregs(thr, fpregset);
1428 #endif
1429 memset(&thrmisc->_pad, 0, sizeof (thrmisc->_pad));
1430 strcpy(thrmisc->pr_tname, thr->td_name);
1431 }
1432 __elfN(putnote)(dst, off, "FreeBSD", NT_PRSTATUS, status,
1433 sizeof *status);
1434 __elfN(putnote)(dst, off, "FreeBSD", NT_FPREGSET, fpregset,
1435 sizeof *fpregset);
1436 __elfN(putnote)(dst, off, "FreeBSD", NT_THRMISC, thrmisc,
1437 sizeof *thrmisc);
1438 /*
1439 * Allow for MD specific notes, as well as any MD
1440 * specific preparations for writing MI notes.
1441 */
1442 __elfN(dump_thread)(thr, dst, off);
1443
1444 thr = (thr == td) ? TAILQ_FIRST(&p->p_threads) :
1445 TAILQ_NEXT(thr, td_plist);
1446 if (thr == td)
1447 thr = TAILQ_NEXT(thr, td_plist);
1448 }
1449
1450 notesz = *off - noteoff;
1451
1452 if (dst != NULL)
1453 free(tempdata, M_TEMP);
1454
1455 /* Align up to a page boundary for the program segments. */
1456 *off = round_page(*off);
1457
1458 if (dst != NULL) {
1459 Elf_Ehdr *ehdr;
1460 Elf_Phdr *phdr;
1461 struct phdr_closure phc;
1462
1463 /*
1464 * Fill in the ELF header.
1465 */
1466 ehdr = (Elf_Ehdr *)((char *)dst + ehoff);
1467 ehdr->e_ident[EI_MAG0] = ELFMAG0;
1468 ehdr->e_ident[EI_MAG1] = ELFMAG1;
1469 ehdr->e_ident[EI_MAG2] = ELFMAG2;
1470 ehdr->e_ident[EI_MAG3] = ELFMAG3;
1471 ehdr->e_ident[EI_CLASS] = ELF_CLASS;
1472 ehdr->e_ident[EI_DATA] = ELF_DATA;
1473 ehdr->e_ident[EI_VERSION] = EV_CURRENT;
1474 ehdr->e_ident[EI_OSABI] = ELFOSABI_FREEBSD;
1475 ehdr->e_ident[EI_ABIVERSION] = 0;
1476 ehdr->e_ident[EI_PAD] = 0;
1477 ehdr->e_type = ET_CORE;
1478 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32
1479 ehdr->e_machine = ELF_ARCH32;
1480 #else
1481 ehdr->e_machine = ELF_ARCH;
1482 #endif
1483 ehdr->e_version = EV_CURRENT;
1484 ehdr->e_entry = 0;
1485 ehdr->e_phoff = phoff;
1486 ehdr->e_flags = 0;
1487 ehdr->e_ehsize = sizeof(Elf_Ehdr);
1488 ehdr->e_phentsize = sizeof(Elf_Phdr);
1489 ehdr->e_phnum = numsegs + 1;
1490 ehdr->e_shentsize = sizeof(Elf_Shdr);
1491 ehdr->e_shnum = 0;
1492 ehdr->e_shstrndx = SHN_UNDEF;
1493
1494 /*
1495 * Fill in the program header entries.
1496 */
1497 phdr = (Elf_Phdr *)((char *)dst + phoff);
1498
1499 /* The note segement. */
1500 phdr->p_type = PT_NOTE;
1501 phdr->p_offset = noteoff;
1502 phdr->p_vaddr = 0;
1503 phdr->p_paddr = 0;
1504 phdr->p_filesz = notesz;
1505 phdr->p_memsz = 0;
1506 phdr->p_flags = 0;
1507 phdr->p_align = 0;
1508 phdr++;
1509
1510 /* All the writable segments from the program. */
1511 phc.phdr = phdr;
1512 phc.offset = *off;
1513 each_writable_segment(td, cb_put_phdr, &phc);
1514 }
1515 }
1516
1517 static void
1518 __elfN(putnote)(void *dst, size_t *off, const char *name, int type,
1519 const void *desc, size_t descsz)
1520 {
1521 Elf_Note note;
1522
1523 note.n_namesz = strlen(name) + 1;
1524 note.n_descsz = descsz;
1525 note.n_type = type;
1526 if (dst != NULL)
1527 bcopy(¬e, (char *)dst + *off, sizeof note);
1528 *off += sizeof note;
1529 if (dst != NULL)
1530 bcopy(name, (char *)dst + *off, note.n_namesz);
1531 *off += roundup2(note.n_namesz, sizeof(Elf_Size));
1532 if (dst != NULL)
1533 bcopy(desc, (char *)dst + *off, note.n_descsz);
1534 *off += roundup2(note.n_descsz, sizeof(Elf_Size));
1535 }
1536
1537 /*
1538 * Try to find the appropriate ABI-note section for checknote,
1539 * fetch the osreldate for binary from the ELF OSABI-note. Only the
1540 * first page of the image is searched, the same as for headers.
1541 */
1542 static boolean_t
1543 __elfN(check_note)(struct image_params *imgp, Elf_Brandnote *checknote,
1544 int32_t *osrel)
1545 {
1546 const Elf_Note *note, *note0, *note_end;
1547 const Elf_Phdr *phdr, *pnote;
1548 const Elf_Ehdr *hdr;
1549 const char *note_name;
1550 int i;
1551
1552 pnote = NULL;
1553 hdr = (const Elf_Ehdr *)imgp->image_header;
1554 phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff);
1555
1556 for (i = 0; i < hdr->e_phnum; i++) {
1557 if (phdr[i].p_type == PT_NOTE) {
1558 pnote = &phdr[i];
1559 break;
1560 }
1561 }
1562
1563 if (pnote == NULL || pnote->p_offset >= PAGE_SIZE ||
1564 pnote->p_offset + pnote->p_filesz >= PAGE_SIZE)
1565 return (FALSE);
1566
1567 note = note0 = (const Elf_Note *)(imgp->image_header + pnote->p_offset);
1568 note_end = (const Elf_Note *)(imgp->image_header +
1569 pnote->p_offset + pnote->p_filesz);
1570 for (i = 0; i < 100 && note >= note0 && note < note_end; i++) {
1571 if (!aligned(note, Elf32_Addr))
1572 return (FALSE);
1573 if (note->n_namesz != checknote->hdr.n_namesz ||
1574 note->n_descsz != checknote->hdr.n_descsz ||
1575 note->n_type != checknote->hdr.n_type)
1576 goto nextnote;
1577 note_name = (const char *)(note + 1);
1578 if (strncmp(checknote->vendor, note_name,
1579 checknote->hdr.n_namesz) != 0)
1580 goto nextnote;
1581
1582 /*
1583 * Fetch the osreldate for binary
1584 * from the ELF OSABI-note if necessary.
1585 */
1586 if ((checknote->flags & BN_TRANSLATE_OSREL) != 0 &&
1587 checknote->trans_osrel != NULL)
1588 return (checknote->trans_osrel(note, osrel));
1589 return (TRUE);
1590
1591 nextnote:
1592 note = (const Elf_Note *)((const char *)(note + 1) +
1593 roundup2(note->n_namesz, sizeof(Elf32_Addr)) +
1594 roundup2(note->n_descsz, sizeof(Elf32_Addr)));
1595 }
1596
1597 return (FALSE);
1598 }
1599
1600 /*
1601 * Tell kern_execve.c about it, with a little help from the linker.
1602 */
1603 static struct execsw __elfN(execsw) = {
1604 __CONCAT(exec_, __elfN(imgact)),
1605 __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE))
1606 };
1607 EXEC_SET(__CONCAT(elf, __ELF_WORD_SIZE), __elfN(execsw));
1608
1609 #ifdef COMPRESS_USER_CORES
1610 /*
1611 * Compress and write out a core segment for a user process.
1612 *
1613 * 'inbuf' is the starting address of a VM segment in the process' address
1614 * space that is to be compressed and written out to the core file. 'dest_buf'
1615 * is a buffer in the kernel's address space. The segment is copied from
1616 * 'inbuf' to 'dest_buf' first before being processed by the compression
1617 * routine gzwrite(). This copying is necessary because the content of the VM
1618 * segment may change between the compression pass and the crc-computation pass
1619 * in gzwrite(). This is because realtime threads may preempt the UNIX kernel.
1620 */
1621 static int
1622 compress_core (gzFile file, char *inbuf, char *dest_buf, unsigned int len,
1623 struct thread *td)
1624 {
1625 int len_compressed;
1626 int error = 0;
1627 unsigned int chunk_len;
1628
1629 while (len) {
1630 chunk_len = (len > CORE_BUF_SIZE) ? CORE_BUF_SIZE : len;
1631 copyin(inbuf, dest_buf, chunk_len);
1632 len_compressed = gzwrite(file, dest_buf, chunk_len);
1633
1634 EVENTHANDLER_INVOKE(app_coredump_progress, td, len_compressed);
1635
1636 if ((unsigned int)len_compressed != chunk_len) {
1637 log(LOG_WARNING,
1638 "compress_core: length mismatch (0x%x returned, "
1639 "0x%x expected)\n", len_compressed, chunk_len);
1640 EVENTHANDLER_INVOKE(app_coredump_error, td,
1641 "compress_core: length mismatch %x -> %x",
1642 chunk_len, len_compressed);
1643 error = EFAULT;
1644 break;
1645 }
1646 inbuf += chunk_len;
1647 len -= chunk_len;
1648 maybe_yield();
1649 }
1650
1651 return (error);
1652 }
1653 #endif /* COMPRESS_USER_CORES */
1654
1655 static vm_prot_t
1656 __elfN(trans_prot)(Elf_Word flags)
1657 {
1658 vm_prot_t prot;
1659
1660 prot = 0;
1661 if (flags & PF_X)
1662 prot |= VM_PROT_EXECUTE;
1663 if (flags & PF_W)
1664 prot |= VM_PROT_WRITE;
1665 if (flags & PF_R)
1666 prot |= VM_PROT_READ;
1667 return (prot);
1668 }
1669
1670 static Elf_Word
1671 __elfN(untrans_prot)(vm_prot_t prot)
1672 {
1673 Elf_Word flags;
1674
1675 flags = 0;
1676 if (prot & VM_PROT_EXECUTE)
1677 flags |= PF_X;
1678 if (prot & VM_PROT_READ)
1679 flags |= PF_R;
1680 if (prot & VM_PROT_WRITE)
1681 flags |= PF_W;
1682 return (flags);
1683 }
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