xref: /netbsd/sys/kern/exec_elf32.c (revision c4a72b64)
1 /*	$NetBSD: exec_elf32.c,v 1.77 2002/11/13 15:49:44 jdolecek Exp $	*/
2 
3 /*-
4  * Copyright (c) 1994, 2000 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Christos Zoulas.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the NetBSD
21  *	Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 /*
40  * Copyright (c) 1996 Christopher G. Demetriou
41  * All rights reserved.
42  *
43  * Redistribution and use in source and binary forms, with or without
44  * modification, are permitted provided that the following conditions
45  * are met:
46  * 1. Redistributions of source code must retain the above copyright
47  *    notice, this list of conditions and the following disclaimer.
48  * 2. Redistributions in binary form must reproduce the above copyright
49  *    notice, this list of conditions and the following disclaimer in the
50  *    documentation and/or other materials provided with the distribution.
51  * 3. The name of the author may not be used to endorse or promote products
52  *    derived from this software without specific prior written permission
53  *
54  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
55  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
56  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
57  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
58  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
59  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
60  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
61  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
62  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
63  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
64  */
65 
66 #include <sys/cdefs.h>
67 __KERNEL_RCSID(1, "$NetBSD: exec_elf32.c,v 1.77 2002/11/13 15:49:44 jdolecek Exp $");
68 
69 /* If not included by exec_elf64.c, ELFSIZE won't be defined. */
70 #ifndef ELFSIZE
71 #define	ELFSIZE		32
72 #endif
73 
74 #include <sys/param.h>
75 #include <sys/proc.h>
76 #include <sys/malloc.h>
77 #include <sys/namei.h>
78 #include <sys/vnode.h>
79 #include <sys/exec.h>
80 #include <sys/exec_elf.h>
81 #include <sys/syscall.h>
82 #include <sys/signalvar.h>
83 #include <sys/mount.h>
84 #include <sys/stat.h>
85 
86 #include <machine/cpu.h>
87 #include <machine/reg.h>
88 
89 extern const struct emul emul_netbsd;
90 
91 int	ELFNAME(check_header)(Elf_Ehdr *, int);
92 int	ELFNAME(load_file)(struct proc *, struct exec_package *, char *,
93 	    struct exec_vmcmd_set *, u_long *, struct elf_args *, Elf_Addr *);
94 void	ELFNAME(load_psection)(struct exec_vmcmd_set *, struct vnode *,
95 	    const Elf_Phdr *, Elf_Addr *, u_long *, int *, int);
96 
97 int ELFNAME2(netbsd,signature)(struct proc *, struct exec_package *,
98     Elf_Ehdr *);
99 int ELFNAME2(netbsd,probe)(struct proc *, struct exec_package *,
100     void *, char *, vaddr_t *);
101 
102 /* round up and down to page boundaries. */
103 #define	ELF_ROUND(a, b)		(((a) + (b) - 1) & ~((b) - 1))
104 #define	ELF_TRUNC(a, b)		((a) & ~((b) - 1))
105 
106 /*
107  * Copy arguments onto the stack in the normal way, but add some
108  * extra information in case of dynamic binding.
109  */
110 int
111 ELFNAME(copyargs)(struct proc *p, struct exec_package *pack,
112     struct ps_strings *arginfo, char **stackp, void *argp)
113 {
114 	size_t len;
115 	AuxInfo ai[ELF_AUX_ENTRIES], *a;
116 	struct elf_args *ap;
117 	int error;
118 
119 	if ((error = copyargs(p, pack, arginfo, stackp, argp)) != 0)
120 		return error;
121 
122 	a = ai;
123 
124 	/*
125 	 * Push extra arguments on the stack needed by dynamically
126 	 * linked binaries
127 	 */
128 	if ((ap = (struct elf_args *)pack->ep_emul_arg)) {
129 		struct vattr *vap = pack->ep_vap;
130 
131 		a->a_type = AT_PHDR;
132 		a->a_v = ap->arg_phaddr;
133 		a++;
134 
135 		a->a_type = AT_PHENT;
136 		a->a_v = ap->arg_phentsize;
137 		a++;
138 
139 		a->a_type = AT_PHNUM;
140 		a->a_v = ap->arg_phnum;
141 		a++;
142 
143 		a->a_type = AT_PAGESZ;
144 		a->a_v = PAGE_SIZE;
145 		a++;
146 
147 		a->a_type = AT_BASE;
148 		a->a_v = ap->arg_interp;
149 		a++;
150 
151 		a->a_type = AT_FLAGS;
152 		a->a_v = 0;
153 		a++;
154 
155 		a->a_type = AT_ENTRY;
156 		a->a_v = ap->arg_entry;
157 		a++;
158 
159 		a->a_type = AT_EUID;
160 		if (vap->va_mode & S_ISUID)
161 			a->a_v = vap->va_uid;
162 		else
163 			a->a_v = p->p_ucred->cr_uid;
164 		a++;
165 
166 		a->a_type = AT_RUID;
167 		a->a_v = p->p_cred->p_ruid;
168 		a++;
169 
170 		a->a_type = AT_EGID;
171 		if (vap->va_mode & S_ISGID)
172 			a->a_v = vap->va_gid;
173 		else
174 			a->a_v = p->p_ucred->cr_gid;
175 		a++;
176 
177 		a->a_type = AT_RGID;
178 		a->a_v = p->p_cred->p_rgid;
179 		a++;
180 
181 		free(ap, M_TEMP);
182 		pack->ep_emul_arg = NULL;
183 	}
184 
185 	a->a_type = AT_NULL;
186 	a->a_v = 0;
187 	a++;
188 
189 	len = (a - ai) * sizeof(AuxInfo);
190 	if ((error = copyout(ai, *stackp, len)) != 0)
191 		return error;
192 	*stackp += len;
193 
194 	return 0;
195 }
196 
197 /*
198  * elf_check_header():
199  *
200  * Check header for validity; return 0 of ok ENOEXEC if error
201  */
202 int
203 ELFNAME(check_header)(Elf_Ehdr *eh, int type)
204 {
205 
206 	if (memcmp(eh->e_ident, ELFMAG, SELFMAG) != 0 ||
207 	    eh->e_ident[EI_CLASS] != ELFCLASS)
208 		return (ENOEXEC);
209 
210 	switch (eh->e_machine) {
211 
212 	ELFDEFNNAME(MACHDEP_ID_CASES)
213 
214 	default:
215 		return (ENOEXEC);
216 	}
217 
218 	if (ELF_EHDR_FLAGS_OK(eh) == 0)
219 		return (ENOEXEC);
220 
221 	if (eh->e_type != type)
222 		return (ENOEXEC);
223 
224 	if (eh->e_shnum > 512 ||
225 	    eh->e_phnum > 128)
226 		return (ENOEXEC);
227 
228 	return (0);
229 }
230 
231 /*
232  * elf_load_psection():
233  *
234  * Load a psection at the appropriate address
235  */
236 void
237 ELFNAME(load_psection)(struct exec_vmcmd_set *vcset, struct vnode *vp,
238     const Elf_Phdr *ph, Elf_Addr *addr, u_long *size, int *prot, int flags)
239 {
240 	u_long uaddr, msize, psize, rm, rf;
241 	long diff, offset;
242 
243 	/*
244 	 * If the user specified an address, then we load there.
245 	 */
246 	if (*addr != ELFDEFNNAME(NO_ADDR)) {
247 		if (ph->p_align > 1) {
248 			*addr = ELF_TRUNC(*addr, ph->p_align);
249 			uaddr = ELF_TRUNC(ph->p_vaddr, ph->p_align);
250 		} else
251 			uaddr = ph->p_vaddr;
252 		diff = ph->p_vaddr - uaddr;
253 	} else {
254 		*addr = uaddr = ph->p_vaddr;
255 		if (ph->p_align > 1)
256 			*addr = ELF_TRUNC(uaddr, ph->p_align);
257 		diff = uaddr - *addr;
258 	}
259 
260 	*prot |= (ph->p_flags & PF_R) ? VM_PROT_READ : 0;
261 	*prot |= (ph->p_flags & PF_W) ? VM_PROT_WRITE : 0;
262 	*prot |= (ph->p_flags & PF_X) ? VM_PROT_EXECUTE : 0;
263 
264 	offset = ph->p_offset - diff;
265 	*size = ph->p_filesz + diff;
266 	msize = ph->p_memsz + diff;
267 
268 	if (ph->p_align >= PAGE_SIZE) {
269 		if ((ph->p_flags & PF_W) != 0) {
270 			/*
271 			 * Because the pagedvn pager can't handle zero fill
272 			 * of the last data page if it's not page aligned we
273 			 * map the last page readvn.
274 			 */
275 			psize = trunc_page(*size);
276 		} else {
277 			psize = round_page(*size);
278 		}
279 	} else {
280 		psize = *size;
281 	}
282 
283 	if (psize > 0) {
284 		NEW_VMCMD2(vcset, ph->p_align < PAGE_SIZE ?
285 		    vmcmd_map_readvn : vmcmd_map_pagedvn, psize, *addr, vp,
286 		    offset, *prot, flags);
287 	}
288 	if (psize < *size) {
289 		NEW_VMCMD2(vcset, vmcmd_map_readvn, *size - psize,
290 		    *addr + psize, vp, offset + psize, *prot,
291 		    psize > 0 ? flags & VMCMD_RELATIVE : flags);
292 	}
293 
294 	/*
295 	 * Check if we need to extend the size of the segment
296 	 */
297 	rm = round_page(*addr + msize);
298 	rf = round_page(*addr + *size);
299 
300 	if (rm != rf) {
301 		NEW_VMCMD2(vcset, vmcmd_map_zero, rm - rf, rf, NULLVP,
302 		    0, *prot, flags & VMCMD_RELATIVE);
303 		*size = msize;
304 	}
305 }
306 
307 /*
308  * elf_load_file():
309  *
310  * Load a file (interpreter/library) pointed to by path
311  * [stolen from coff_load_shlib()]. Made slightly generic
312  * so it might be used externally.
313  */
314 int
315 ELFNAME(load_file)(struct proc *p, struct exec_package *epp, char *path,
316     struct exec_vmcmd_set *vcset, u_long *entry, struct elf_args *ap,
317     Elf_Addr *last)
318 {
319 	int error, i;
320 	struct nameidata nd;
321 	struct vnode *vp;
322 	struct vattr attr;
323 	Elf_Ehdr eh;
324 	Elf_Phdr *ph = NULL;
325 	Elf_Phdr *base_ph = NULL;
326 	u_long phsize;
327 	char *bp = NULL;
328 	Elf_Addr addr = *last;
329 
330 	bp = path;
331 	/*
332 	 * 1. open file
333 	 * 2. read filehdr
334 	 * 3. map text, data, and bss out of it using VM_*
335 	 */
336 	NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, path, p);
337 	if ((error = namei(&nd)) != 0)
338 		return error;
339 	vp = nd.ni_vp;
340 
341 	/*
342 	 * Similarly, if it's not marked as executable, or it's not a regular
343 	 * file, we don't allow it to be used.
344 	 */
345 	if (vp->v_type != VREG) {
346 		error = EACCES;
347 		goto badunlock;
348 	}
349 	if ((error = VOP_ACCESS(vp, VEXEC, p->p_ucred, p)) != 0)
350 		goto badunlock;
351 
352 	/* get attributes */
353 	if ((error = VOP_GETATTR(vp, &attr, p->p_ucred, p)) != 0)
354 		goto badunlock;
355 
356 	/*
357 	 * Check mount point.  Though we're not trying to exec this binary,
358 	 * we will be executing code from it, so if the mount point
359 	 * disallows execution or set-id-ness, we punt or kill the set-id.
360 	 */
361 	if (vp->v_mount->mnt_flag & MNT_NOEXEC) {
362 		error = EACCES;
363 		goto badunlock;
364 	}
365 	if (vp->v_mount->mnt_flag & MNT_NOSUID)
366 		epp->ep_vap->va_mode &= ~(S_ISUID | S_ISGID);
367 
368 #ifdef notyet /* XXX cgd 960926 */
369 	XXX cgd 960926: (maybe) VOP_OPEN it (and VOP_CLOSE in copyargs?)
370 #endif
371 
372 	error = vn_marktext(vp);
373 	if (error)
374 		goto badunlock;
375 
376 	VOP_UNLOCK(vp, 0);
377 
378 	if ((error = exec_read_from(p, vp, 0, &eh, sizeof(eh))) != 0)
379 		goto bad;
380 
381 	if ((error = ELFNAME(check_header)(&eh, ET_DYN)) != 0)
382 		goto bad;
383 
384 	phsize = eh.e_phnum * sizeof(Elf_Phdr);
385 	ph = (Elf_Phdr *)malloc(phsize, M_TEMP, M_WAITOK);
386 
387 	if ((error = exec_read_from(p, vp, eh.e_phoff, ph, phsize)) != 0)
388 		goto bad;
389 
390 	/*
391 	 * Load all the necessary sections
392 	 */
393 	for (i = 0; i < eh.e_phnum; i++) {
394 		u_long size = 0;
395 		int prot = 0;
396 		int flags;
397 
398 		switch (ph[i].p_type) {
399 		case PT_LOAD:
400 			if (base_ph == NULL) {
401 				addr = *last;
402 				flags = VMCMD_BASE;
403 			} else {
404 				addr = ph[i].p_vaddr - base_ph->p_vaddr;
405 				flags = VMCMD_RELATIVE;
406 			}
407 			ELFNAME(load_psection)(vcset, vp, &ph[i], &addr,
408 			    &size, &prot, flags);
409 			/* If entry is within this section it must be text */
410 			if (eh.e_entry >= ph[i].p_vaddr &&
411 			    eh.e_entry < (ph[i].p_vaddr + size)) {
412 				*entry = addr + eh.e_entry - ph[i].p_vaddr;
413 				ap->arg_interp = addr;
414 			}
415 			if (base_ph == NULL)
416 				base_ph = &ph[i];
417 			addr += size;
418 			break;
419 
420 		case PT_DYNAMIC:
421 		case PT_PHDR:
422 		case PT_NOTE:
423 			break;
424 
425 		default:
426 			break;
427 		}
428 	}
429 
430 	free(ph, M_TEMP);
431 	*last = addr;
432 	vrele(vp);
433 	return 0;
434 
435 badunlock:
436 	VOP_UNLOCK(vp, 0);
437 
438 bad:
439 	if (ph != NULL)
440 		free(ph, M_TEMP);
441 #ifdef notyet /* XXX cgd 960926 */
442 	(maybe) VOP_CLOSE it
443 #endif
444 	vrele(vp);
445 	return error;
446 }
447 
448 /*
449  * exec_elf_makecmds(): Prepare an Elf binary's exec package
450  *
451  * First, set of the various offsets/lengths in the exec package.
452  *
453  * Then, mark the text image busy (so it can be demand paged) or error
454  * out if this is not possible.  Finally, set up vmcmds for the
455  * text, data, bss, and stack segments.
456  */
457 int
458 ELFNAME2(exec,makecmds)(struct proc *p, struct exec_package *epp)
459 {
460 	Elf_Ehdr *eh = epp->ep_hdr;
461 	Elf_Phdr *ph, *pp;
462 	Elf_Addr phdr = 0, pos = 0;
463 	int error, i, nload;
464 	char *interp = NULL;
465 	u_long phsize;
466 
467 	if (epp->ep_hdrvalid < sizeof(Elf_Ehdr))
468 		return ENOEXEC;
469 
470 	/*
471 	 * XXX allow for executing shared objects. It seems silly
472 	 * but other ELF-based systems allow it as well.
473 	 */
474 	if (ELFNAME(check_header)(eh, ET_EXEC) != 0 &&
475 	    ELFNAME(check_header)(eh, ET_DYN) != 0)
476 		return ENOEXEC;
477 
478 	error = vn_marktext(epp->ep_vp);
479 	if (error)
480 		return (error);
481 
482 	/*
483 	 * Allocate space to hold all the program headers, and read them
484 	 * from the file
485 	 */
486 	phsize = eh->e_phnum * sizeof(Elf_Phdr);
487 	ph = (Elf_Phdr *)malloc(phsize, M_TEMP, M_WAITOK);
488 
489 	if ((error = exec_read_from(p, epp->ep_vp, eh->e_phoff, ph, phsize)) !=
490 	    0)
491 		goto bad;
492 
493 	epp->ep_taddr = epp->ep_tsize = ELFDEFNNAME(NO_ADDR);
494 	epp->ep_daddr = epp->ep_dsize = ELFDEFNNAME(NO_ADDR);
495 
496 	MALLOC(interp, char *, MAXPATHLEN, M_TEMP, M_WAITOK);
497 	interp[0] = '\0';
498 
499 	for (i = 0; i < eh->e_phnum; i++) {
500 		pp = &ph[i];
501 		if (pp->p_type == PT_INTERP) {
502 			if (pp->p_filesz >= MAXPATHLEN)
503 				goto bad;
504 			if ((error = exec_read_from(p, epp->ep_vp,
505 			    pp->p_offset, interp, pp->p_filesz)) != 0)
506 				goto bad;
507 			break;
508 		}
509 	}
510 
511 	/*
512 	 * On the same architecture, we may be emulating different systems.
513 	 * See which one will accept this executable. This currently only
514 	 * applies to SVR4, and IBCS2 on the i386 and Linux on the i386
515 	 * and the Alpha.
516 	 *
517 	 * Probe functions would normally see if the interpreter (if any)
518 	 * exists. Emulation packages may possibly replace the interpreter in
519 	 * interp[] with a changed path (/emul/xxx/<path>).
520 	 */
521 	if (!epp->ep_esch->u.elf_probe_func) {
522 		pos = ELFDEFNNAME(NO_ADDR);
523 	} else {
524 		vaddr_t startp = 0;
525 
526 		error = (*epp->ep_esch->u.elf_probe_func)(p, epp, eh, interp,
527 							  &startp);
528 		pos = (Elf_Addr)startp;
529 		if (error)
530 			goto bad;
531 	}
532 
533 	/*
534 	 * Load all the necessary sections
535 	 */
536 	for (i = nload = 0; i < eh->e_phnum; i++) {
537 		Elf_Addr  addr = ELFDEFNNAME(NO_ADDR);
538 		u_long size = 0;
539 		int prot = 0;
540 
541 		pp = &ph[i];
542 
543 		switch (ph[i].p_type) {
544 		case PT_LOAD:
545 			/*
546 			 * XXX
547 			 * Can handle only 2 sections: text and data
548 			 */
549 			if (nload++ == 2)
550 				goto bad;
551 			ELFNAME(load_psection)(&epp->ep_vmcmds, epp->ep_vp,
552 			    &ph[i], &addr, &size, &prot, 0);
553 
554 			/*
555 			 * Decide whether it's text or data by looking
556 			 * at the entry point.
557 			 */
558 			if (eh->e_entry >= addr &&
559 			    eh->e_entry < (addr + size)) {
560 				epp->ep_taddr = addr;
561 				epp->ep_tsize = size;
562 				if (epp->ep_daddr == ELFDEFNNAME(NO_ADDR)) {
563 					epp->ep_daddr = addr;
564 					epp->ep_dsize = size;
565 				}
566 			} else {
567 				epp->ep_daddr = addr;
568 				epp->ep_dsize = size;
569 			}
570 			break;
571 
572 		case PT_SHLIB:
573 			/* SCO has these sections. */
574 		case PT_INTERP:
575 			/* Already did this one. */
576 		case PT_DYNAMIC:
577 		case PT_NOTE:
578 			break;
579 
580 		case PT_PHDR:
581 			/* Note address of program headers (in text segment) */
582 			phdr = pp->p_vaddr;
583 			break;
584 
585 		default:
586 			/*
587 			 * Not fatal; we don't need to understand everything.
588 			 */
589 			break;
590 		}
591 	}
592 
593 	/* this breaks on, e.g., OpenBSD-compatible mips shared binaries. */
594 #ifndef ELF_INTERP_NON_RELOCATABLE
595 	/*
596 	 * If no position to load the interpreter was set by a probe
597 	 * function, pick the same address that a non-fixed mmap(0, ..)
598 	 * would (i.e. something safely out of the way).
599 	 */
600 	if (pos == ELFDEFNNAME(NO_ADDR))
601 		pos = round_page(epp->ep_daddr + MAXDSIZ);
602 #endif	/* !ELF_INTERP_NON_RELOCATABLE */
603 
604 	/*
605 	 * Check if we found a dynamically linked binary and arrange to load
606 	 * it's interpreter
607 	 */
608 	if (interp[0]) {
609 		struct elf_args *ap;
610 
611 		MALLOC(ap, struct elf_args *, sizeof(struct elf_args),
612 		    M_TEMP, M_WAITOK);
613 		if ((error = ELFNAME(load_file)(p, epp, interp,
614 		    &epp->ep_vmcmds, &epp->ep_entry, ap, &pos)) != 0) {
615 			FREE(ap, M_TEMP);
616 			goto bad;
617 		}
618 		ap->arg_phaddr = phdr;
619 
620 		ap->arg_phentsize = eh->e_phentsize;
621 		ap->arg_phnum = eh->e_phnum;
622 		ap->arg_entry = eh->e_entry;
623 
624 		epp->ep_emul_arg = ap;
625 	} else
626 		epp->ep_entry = eh->e_entry;
627 
628 #ifdef ELF_MAP_PAGE_ZERO
629 	/* Dell SVR4 maps page zero, yeuch! */
630 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, PAGE_SIZE, 0,
631 	    epp->ep_vp, 0, VM_PROT_READ);
632 #endif
633 	FREE(interp, M_TEMP);
634 	free(ph, M_TEMP);
635 	return exec_elf_setup_stack(p, epp);
636 
637 bad:
638 	if (interp)
639 		FREE(interp, M_TEMP);
640 	free(ph, M_TEMP);
641 	kill_vmcmds(&epp->ep_vmcmds);
642 	return ENOEXEC;
643 }
644 
645 int
646 ELFNAME2(netbsd,signature)(struct proc *p, struct exec_package *epp,
647     Elf_Ehdr *eh)
648 {
649 	size_t i;
650 	Elf_Phdr *ph;
651 	size_t phsize;
652 	int error;
653 
654 	phsize = eh->e_phnum * sizeof(Elf_Phdr);
655 	ph = (Elf_Phdr *)malloc(phsize, M_TEMP, M_WAITOK);
656 	error = exec_read_from(p, epp->ep_vp, eh->e_phoff, ph, phsize);
657 	if (error)
658 		goto out;
659 
660 	for (i = 0; i < eh->e_phnum; i++) {
661 		Elf_Phdr *ephp = &ph[i];
662 		Elf_Nhdr *np;
663 
664 		if (ephp->p_type != PT_NOTE ||
665 		    ephp->p_filesz > 1024 ||
666 		    ephp->p_filesz < sizeof(Elf_Nhdr) + ELF_NOTE_NETBSD_NAMESZ)
667 			continue;
668 
669 		np = (Elf_Nhdr *)malloc(ephp->p_filesz, M_TEMP, M_WAITOK);
670 		error = exec_read_from(p, epp->ep_vp, ephp->p_offset, np,
671 		    ephp->p_filesz);
672 		if (error)
673 			goto next;
674 
675 		if (np->n_type != ELF_NOTE_TYPE_NETBSD_TAG ||
676 		    np->n_namesz != ELF_NOTE_NETBSD_NAMESZ ||
677 		    np->n_descsz != ELF_NOTE_NETBSD_DESCSZ ||
678 		    memcmp((caddr_t)(np + 1), ELF_NOTE_NETBSD_NAME,
679 		    ELF_NOTE_NETBSD_NAMESZ))
680 			goto next;
681 
682 		error = 0;
683 		free(np, M_TEMP);
684 		goto out;
685 
686 	next:
687 		free(np, M_TEMP);
688 		continue;
689 	}
690 
691 	error = ENOEXEC;
692 out:
693 	free(ph, M_TEMP);
694 	return (error);
695 }
696 
697 int
698 ELFNAME2(netbsd,probe)(struct proc *p, struct exec_package *epp,
699     void *eh, char *itp, vaddr_t *pos)
700 {
701 	int error;
702 
703 	if ((error = ELFNAME2(netbsd,signature)(p, epp, eh)) != 0)
704 		return error;
705 	*pos = ELFDEFNNAME(NO_ADDR);
706 	return 0;
707 }
708