Index: head/sys/kern/imgact_elf.c
===================================================================
--- head/sys/kern/imgact_elf.c	(revision 316210)
+++ head/sys/kern/imgact_elf.c	(revision 316211)
@@ -1,2431 +1,2434 @@
 /*-
  * Copyright (c) 2000 David O'Brien
  * Copyright (c) 1995-1996 Søren Schmidt
  * Copyright (c) 1996 Peter Wemm
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer
  *    in this position and unchanged.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  * 3. The name of the author may not be used to endorse or promote products
  *    derived from this software without specific prior written permission
  *
  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
 #include "opt_capsicum.h"
 #include "opt_compat.h"
 #include "opt_gzio.h"
 
 #include <sys/param.h>
 #include <sys/capsicum.h>
 #include <sys/exec.h>
 #include <sys/fcntl.h>
 #include <sys/gzio.h>
 #include <sys/imgact.h>
 #include <sys/imgact_elf.h>
 #include <sys/jail.h>
 #include <sys/kernel.h>
 #include <sys/lock.h>
 #include <sys/malloc.h>
 #include <sys/mount.h>
 #include <sys/mman.h>
 #include <sys/namei.h>
 #include <sys/pioctl.h>
 #include <sys/proc.h>
 #include <sys/procfs.h>
 #include <sys/racct.h>
 #include <sys/resourcevar.h>
 #include <sys/rwlock.h>
 #include <sys/sbuf.h>
 #include <sys/sf_buf.h>
 #include <sys/smp.h>
 #include <sys/systm.h>
 #include <sys/signalvar.h>
 #include <sys/stat.h>
 #include <sys/sx.h>
 #include <sys/syscall.h>
 #include <sys/sysctl.h>
 #include <sys/sysent.h>
 #include <sys/vnode.h>
 #include <sys/syslog.h>
 #include <sys/eventhandler.h>
 #include <sys/user.h>
 
 #include <vm/vm.h>
 #include <vm/vm_kern.h>
 #include <vm/vm_param.h>
 #include <vm/pmap.h>
 #include <vm/vm_map.h>
 #include <vm/vm_object.h>
 #include <vm/vm_extern.h>
 
 #include <machine/elf.h>
 #include <machine/md_var.h>
 
 #define ELF_NOTE_ROUNDSIZE	4
 #define OLD_EI_BRAND	8
 
 static int __elfN(check_header)(const Elf_Ehdr *hdr);
 static Elf_Brandinfo *__elfN(get_brandinfo)(struct image_params *imgp,
     const char *interp, int interp_name_len, int32_t *osrel);
 static int __elfN(load_file)(struct proc *p, const char *file, u_long *addr,
     u_long *entry, size_t pagesize);
 static int __elfN(load_section)(struct image_params *imgp, vm_ooffset_t offset,
     caddr_t vmaddr, size_t memsz, size_t filsz, vm_prot_t prot,
     size_t pagesize);
 static int __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp);
 static boolean_t __elfN(freebsd_trans_osrel)(const Elf_Note *note,
     int32_t *osrel);
 static boolean_t kfreebsd_trans_osrel(const Elf_Note *note, int32_t *osrel);
 static boolean_t __elfN(check_note)(struct image_params *imgp,
     Elf_Brandnote *checknote, int32_t *osrel);
 static vm_prot_t __elfN(trans_prot)(Elf_Word);
 static Elf_Word __elfN(untrans_prot)(vm_prot_t);
 
 SYSCTL_NODE(_kern, OID_AUTO, __CONCAT(elf, __ELF_WORD_SIZE), CTLFLAG_RW, 0,
     "");
 
 #define	CORE_BUF_SIZE	(16 * 1024)
 
 int __elfN(fallback_brand) = -1;
 SYSCTL_INT(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO,
     fallback_brand, CTLFLAG_RWTUN, &__elfN(fallback_brand), 0,
     __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) " brand of last resort");
 
 static int elf_legacy_coredump = 0;
 SYSCTL_INT(_debug, OID_AUTO, __elfN(legacy_coredump), CTLFLAG_RW, 
     &elf_legacy_coredump, 0,
     "include all and only RW pages in core dumps");
 
 int __elfN(nxstack) =
 #if defined(__amd64__) || defined(__powerpc64__) /* both 64 and 32 bit */ || \
     (defined(__arm__) && __ARM_ARCH >= 7) || defined(__aarch64__)
 	1;
 #else
 	0;
 #endif
 SYSCTL_INT(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO,
     nxstack, CTLFLAG_RW, &__elfN(nxstack), 0,
     __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) ": enable non-executable stack");
 
 #if __ELF_WORD_SIZE == 32
 #if defined(__amd64__)
 int i386_read_exec = 0;
 SYSCTL_INT(_kern_elf32, OID_AUTO, read_exec, CTLFLAG_RW, &i386_read_exec, 0,
     "enable execution from readable segments");
 #endif
 #endif
 
 static Elf_Brandinfo *elf_brand_list[MAX_BRANDS];
 
 #define	trunc_page_ps(va, ps)	rounddown2(va, ps)
 #define	round_page_ps(va, ps)	roundup2(va, ps)
 #define	aligned(a, t)	(trunc_page_ps((u_long)(a), sizeof(t)) == (u_long)(a))
 
 static const char FREEBSD_ABI_VENDOR[] = "FreeBSD";
 
 Elf_Brandnote __elfN(freebsd_brandnote) = {
 	.hdr.n_namesz	= sizeof(FREEBSD_ABI_VENDOR),
 	.hdr.n_descsz	= sizeof(int32_t),
 	.hdr.n_type	= NT_FREEBSD_ABI_TAG,
 	.vendor		= FREEBSD_ABI_VENDOR,
 	.flags		= BN_TRANSLATE_OSREL,
 	.trans_osrel	= __elfN(freebsd_trans_osrel)
 };
 
 static boolean_t
 __elfN(freebsd_trans_osrel)(const Elf_Note *note, int32_t *osrel)
 {
 	uintptr_t p;
 
 	p = (uintptr_t)(note + 1);
 	p += roundup2(note->n_namesz, ELF_NOTE_ROUNDSIZE);
 	*osrel = *(const int32_t *)(p);
 
 	return (TRUE);
 }
 
 static const char GNU_ABI_VENDOR[] = "GNU";
 static int GNU_KFREEBSD_ABI_DESC = 3;
 
 Elf_Brandnote __elfN(kfreebsd_brandnote) = {
 	.hdr.n_namesz	= sizeof(GNU_ABI_VENDOR),
 	.hdr.n_descsz	= 16,	/* XXX at least 16 */
 	.hdr.n_type	= 1,
 	.vendor		= GNU_ABI_VENDOR,
 	.flags		= BN_TRANSLATE_OSREL,
 	.trans_osrel	= kfreebsd_trans_osrel
 };
 
 static boolean_t
 kfreebsd_trans_osrel(const Elf_Note *note, int32_t *osrel)
 {
 	const Elf32_Word *desc;
 	uintptr_t p;
 
 	p = (uintptr_t)(note + 1);
 	p += roundup2(note->n_namesz, ELF_NOTE_ROUNDSIZE);
 
 	desc = (const Elf32_Word *)p;
 	if (desc[0] != GNU_KFREEBSD_ABI_DESC)
 		return (FALSE);
 
 	/*
 	 * Debian GNU/kFreeBSD embed the earliest compatible kernel version
 	 * (__FreeBSD_version: <major><two digit minor>Rxx) in the LSB way.
 	 */
 	*osrel = desc[1] * 100000 + desc[2] * 1000 + desc[3];
 
 	return (TRUE);
 }
 
 int
 __elfN(insert_brand_entry)(Elf_Brandinfo *entry)
 {
 	int i;
 
 	for (i = 0; i < MAX_BRANDS; i++) {
 		if (elf_brand_list[i] == NULL) {
 			elf_brand_list[i] = entry;
 			break;
 		}
 	}
 	if (i == MAX_BRANDS) {
 		printf("WARNING: %s: could not insert brandinfo entry: %p\n",
 			__func__, entry);
 		return (-1);
 	}
 	return (0);
 }
 
 int
 __elfN(remove_brand_entry)(Elf_Brandinfo *entry)
 {
 	int i;
 
 	for (i = 0; i < MAX_BRANDS; i++) {
 		if (elf_brand_list[i] == entry) {
 			elf_brand_list[i] = NULL;
 			break;
 		}
 	}
 	if (i == MAX_BRANDS)
 		return (-1);
 	return (0);
 }
 
 int
 __elfN(brand_inuse)(Elf_Brandinfo *entry)
 {
 	struct proc *p;
 	int rval = FALSE;
 
 	sx_slock(&allproc_lock);
 	FOREACH_PROC_IN_SYSTEM(p) {
 		if (p->p_sysent == entry->sysvec) {
 			rval = TRUE;
 			break;
 		}
 	}
 	sx_sunlock(&allproc_lock);
 
 	return (rval);
 }
 
 static Elf_Brandinfo *
 __elfN(get_brandinfo)(struct image_params *imgp, const char *interp,
     int interp_name_len, int32_t *osrel)
 {
 	const Elf_Ehdr *hdr = (const Elf_Ehdr *)imgp->image_header;
 	Elf_Brandinfo *bi, *bi_m;
 	boolean_t ret;
 	int i;
 
 	/*
 	 * We support four types of branding -- (1) the ELF EI_OSABI field
 	 * that SCO added to the ELF spec, (2) FreeBSD 3.x's traditional string
 	 * branding w/in the ELF header, (3) path of the `interp_path'
 	 * field, and (4) the ".note.ABI-tag" ELF section.
 	 */
 
 	/* Look for an ".note.ABI-tag" ELF section */
 	bi_m = NULL;
 	for (i = 0; i < MAX_BRANDS; i++) {
 		bi = elf_brand_list[i];
 		if (bi == NULL)
 			continue;
 		if (interp != NULL && (bi->flags & BI_BRAND_ONLY_STATIC) != 0)
 			continue;
 		if (hdr->e_machine == bi->machine && (bi->flags &
 		    (BI_BRAND_NOTE|BI_BRAND_NOTE_MANDATORY)) != 0) {
 			ret = __elfN(check_note)(imgp, bi->brand_note, osrel);
 			/* Give brand a chance to veto check_note's guess */
 			if (ret && bi->header_supported)
 				ret = bi->header_supported(imgp);
 			/*
 			 * If note checker claimed the binary, but the
 			 * interpreter path in the image does not
 			 * match default one for the brand, try to
 			 * search for other brands with the same
 			 * interpreter.  Either there is better brand
 			 * with the right interpreter, or, failing
 			 * this, we return first brand which accepted
 			 * our note and, optionally, header.
 			 */
-			if (ret && bi_m == NULL && (strlen(bi->interp_path) +
-			    1 != interp_name_len || strncmp(interp,
-			    bi->interp_path, interp_name_len) != 0)) {
+			if (ret && bi_m == NULL && interp != NULL &&
+			    (bi->interp_path == NULL ||
+			    (strlen(bi->interp_path) + 1 != interp_name_len ||
+			    strncmp(interp, bi->interp_path, interp_name_len)
+			    != 0))) {
 				bi_m = bi;
 				ret = 0;
 			}
 			if (ret)
 				return (bi);
 		}
 	}
 	if (bi_m != NULL)
 		return (bi_m);
 
 	/* If the executable has a brand, search for it in the brand list. */
 	for (i = 0; i < MAX_BRANDS; i++) {
 		bi = elf_brand_list[i];
 		if (bi == NULL || (bi->flags & BI_BRAND_NOTE_MANDATORY) != 0 ||
 		    (interp != NULL && (bi->flags & BI_BRAND_ONLY_STATIC) != 0))
 			continue;
 		if (hdr->e_machine == bi->machine &&
 		    (hdr->e_ident[EI_OSABI] == bi->brand ||
 		    (bi->compat_3_brand != NULL &&
 		    strcmp((const char *)&hdr->e_ident[OLD_EI_BRAND],
 		    bi->compat_3_brand) == 0))) {
 			/* Looks good, but give brand a chance to veto */
 			if (!bi->header_supported ||
 			    bi->header_supported(imgp)) {
 				/*
 				 * Again, prefer strictly matching
 				 * interpreter path.
 				 */
 				if (interp_name_len == 0 &&
 				    bi->interp_path == NULL)
 					return (bi);
 				if (bi->interp_path != NULL &&
 				    strlen(bi->interp_path) + 1 ==
 				    interp_name_len && strncmp(interp,
 				    bi->interp_path, interp_name_len) == 0)
 					return (bi);
 				if (bi_m == NULL)
 					bi_m = bi;
 			}
 		}
 	}
 	if (bi_m != NULL)
 		return (bi_m);
 
 	/* No known brand, see if the header is recognized by any brand */
 	for (i = 0; i < MAX_BRANDS; i++) {
 		bi = elf_brand_list[i];
 		if (bi == NULL || bi->flags & BI_BRAND_NOTE_MANDATORY ||
 		    bi->header_supported == NULL)
 			continue;
 		if (hdr->e_machine == bi->machine) {
 			ret = bi->header_supported(imgp);
 			if (ret)
 				return (bi);
 		}
 	}
 
 	/* Lacking a known brand, search for a recognized interpreter. */
 	if (interp != NULL) {
 		for (i = 0; i < MAX_BRANDS; i++) {
 			bi = elf_brand_list[i];
 			if (bi == NULL || (bi->flags &
 			    (BI_BRAND_NOTE_MANDATORY | BI_BRAND_ONLY_STATIC))
 			    != 0)
 				continue;
 			if (hdr->e_machine == bi->machine &&
+			    bi->interp_path != NULL &&
 			    /* ELF image p_filesz includes terminating zero */
 			    strlen(bi->interp_path) + 1 == interp_name_len &&
 			    strncmp(interp, bi->interp_path, interp_name_len)
 			    == 0)
 				return (bi);
 		}
 	}
 
 	/* Lacking a recognized interpreter, try the default brand */
 	for (i = 0; i < MAX_BRANDS; i++) {
 		bi = elf_brand_list[i];
 		if (bi == NULL || (bi->flags & BI_BRAND_NOTE_MANDATORY) != 0 ||
 		    (interp != NULL && (bi->flags & BI_BRAND_ONLY_STATIC) != 0))
 			continue;
 		if (hdr->e_machine == bi->machine &&
 		    __elfN(fallback_brand) == bi->brand)
 			return (bi);
 	}
 	return (NULL);
 }
 
 static int
 __elfN(check_header)(const Elf_Ehdr *hdr)
 {
 	Elf_Brandinfo *bi;
 	int i;
 
 	if (!IS_ELF(*hdr) ||
 	    hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS ||
 	    hdr->e_ident[EI_DATA] != ELF_TARG_DATA ||
 	    hdr->e_ident[EI_VERSION] != EV_CURRENT ||
 	    hdr->e_phentsize != sizeof(Elf_Phdr) ||
 	    hdr->e_version != ELF_TARG_VER)
 		return (ENOEXEC);
 
 	/*
 	 * Make sure we have at least one brand for this machine.
 	 */
 
 	for (i = 0; i < MAX_BRANDS; i++) {
 		bi = elf_brand_list[i];
 		if (bi != NULL && bi->machine == hdr->e_machine)
 			break;
 	}
 	if (i == MAX_BRANDS)
 		return (ENOEXEC);
 
 	return (0);
 }
 
 static int
 __elfN(map_partial)(vm_map_t map, vm_object_t object, vm_ooffset_t offset,
     vm_offset_t start, vm_offset_t end, vm_prot_t prot)
 {
 	struct sf_buf *sf;
 	int error;
 	vm_offset_t off;
 
 	/*
 	 * Create the page if it doesn't exist yet. Ignore errors.
 	 */
 	vm_map_fixed(map, NULL, 0, trunc_page(start), round_page(end) -
 	    trunc_page(start), VM_PROT_ALL, VM_PROT_ALL, MAP_CHECK_EXCL);
 
 	/*
 	 * Find the page from the underlying object.
 	 */
 	if (object != NULL) {
 		sf = vm_imgact_map_page(object, offset);
 		if (sf == NULL)
 			return (KERN_FAILURE);
 		off = offset - trunc_page(offset);
 		error = copyout((caddr_t)sf_buf_kva(sf) + off, (caddr_t)start,
 		    end - start);
 		vm_imgact_unmap_page(sf);
 		if (error != 0)
 			return (KERN_FAILURE);
 	}
 
 	return (KERN_SUCCESS);
 }
 
 static int
 __elfN(map_insert)(struct image_params *imgp, vm_map_t map, vm_object_t object,
     vm_ooffset_t offset, vm_offset_t start, vm_offset_t end, vm_prot_t prot,
     int cow)
 {
 	struct sf_buf *sf;
 	vm_offset_t off;
 	vm_size_t sz;
 	int error, locked, rv;
 
 	if (start != trunc_page(start)) {
 		rv = __elfN(map_partial)(map, object, offset, start,
 		    round_page(start), prot);
 		if (rv != KERN_SUCCESS)
 			return (rv);
 		offset += round_page(start) - start;
 		start = round_page(start);
 	}
 	if (end != round_page(end)) {
 		rv = __elfN(map_partial)(map, object, offset +
 		    trunc_page(end) - start, trunc_page(end), end, prot);
 		if (rv != KERN_SUCCESS)
 			return (rv);
 		end = trunc_page(end);
 	}
 	if (start >= end)
 		return (KERN_SUCCESS);
 	if ((offset & PAGE_MASK) != 0) {
 		/*
 		 * The mapping is not page aligned.  This means that we have
 		 * to copy the data.
 		 */
 		rv = vm_map_fixed(map, NULL, 0, start, end - start,
 		    prot | VM_PROT_WRITE, VM_PROT_ALL, MAP_CHECK_EXCL);
 		if (rv != KERN_SUCCESS)
 			return (rv);
 		if (object == NULL)
 			return (KERN_SUCCESS);
 		for (; start < end; start += sz) {
 			sf = vm_imgact_map_page(object, offset);
 			if (sf == NULL)
 				return (KERN_FAILURE);
 			off = offset - trunc_page(offset);
 			sz = end - start;
 			if (sz > PAGE_SIZE - off)
 				sz = PAGE_SIZE - off;
 			error = copyout((caddr_t)sf_buf_kva(sf) + off,
 			    (caddr_t)start, sz);
 			vm_imgact_unmap_page(sf);
 			if (error != 0)
 				return (KERN_FAILURE);
 			offset += sz;
 		}
 	} else {
 		vm_object_reference(object);
 		rv = vm_map_fixed(map, object, offset, start, end - start,
 		    prot, VM_PROT_ALL, cow | MAP_CHECK_EXCL);
 		if (rv != KERN_SUCCESS) {
 			locked = VOP_ISLOCKED(imgp->vp);
 			VOP_UNLOCK(imgp->vp, 0);
 			vm_object_deallocate(object);
 			vn_lock(imgp->vp, locked | LK_RETRY);
 			return (rv);
 		}
 	}
 	return (KERN_SUCCESS);
 }
 
 static int
 __elfN(load_section)(struct image_params *imgp, vm_ooffset_t offset,
     caddr_t vmaddr, size_t memsz, size_t filsz, vm_prot_t prot,
     size_t pagesize)
 {
 	struct sf_buf *sf;
 	size_t map_len;
 	vm_map_t map;
 	vm_object_t object;
 	vm_offset_t off, map_addr;
 	int error, rv, cow;
 	size_t copy_len;
 	vm_ooffset_t file_addr;
 
 	/*
 	 * It's necessary to fail if the filsz + offset taken from the
 	 * header is greater than the actual file pager object's size.
 	 * If we were to allow this, then the vm_map_find() below would
 	 * walk right off the end of the file object and into the ether.
 	 *
 	 * While I'm here, might as well check for something else that
 	 * is invalid: filsz cannot be greater than memsz.
 	 */
 	if ((filsz != 0 && (off_t)filsz + offset > imgp->attr->va_size) ||
 	    filsz > memsz) {
 		uprintf("elf_load_section: truncated ELF file\n");
 		return (ENOEXEC);
 	}
 
 	object = imgp->object;
 	map = &imgp->proc->p_vmspace->vm_map;
 	map_addr = trunc_page_ps((vm_offset_t)vmaddr, pagesize);
 	file_addr = trunc_page_ps(offset, pagesize);
 
 	/*
 	 * We have two choices.  We can either clear the data in the last page
 	 * of an oversized mapping, or we can start the anon mapping a page
 	 * early and copy the initialized data into that first page.  We
 	 * choose the second.
 	 */
 	if (filsz == 0)
 		map_len = 0;
 	else if (memsz > filsz)
 		map_len = trunc_page_ps(offset + filsz, pagesize) - file_addr;
 	else
 		map_len = round_page_ps(offset + filsz, pagesize) - file_addr;
 
 	if (map_len != 0) {
 		/* cow flags: don't dump readonly sections in core */
 		cow = MAP_COPY_ON_WRITE | MAP_PREFAULT |
 		    (prot & VM_PROT_WRITE ? 0 : MAP_DISABLE_COREDUMP);
 
 		rv = __elfN(map_insert)(imgp, map,
 				      object,
 				      file_addr,	/* file offset */
 				      map_addr,		/* virtual start */
 				      map_addr + map_len,/* virtual end */
 				      prot,
 				      cow);
 		if (rv != KERN_SUCCESS)
 			return (EINVAL);
 
 		/* we can stop now if we've covered it all */
 		if (memsz == filsz)
 			return (0);
 	}
 
 
 	/*
 	 * We have to get the remaining bit of the file into the first part
 	 * of the oversized map segment.  This is normally because the .data
 	 * segment in the file is extended to provide bss.  It's a neat idea
 	 * to try and save a page, but it's a pain in the behind to implement.
 	 */
 	copy_len = filsz == 0 ? 0 : (offset + filsz) - trunc_page_ps(offset +
 	    filsz, pagesize);
 	map_addr = trunc_page_ps((vm_offset_t)vmaddr + filsz, pagesize);
 	map_len = round_page_ps((vm_offset_t)vmaddr + memsz, pagesize) -
 	    map_addr;
 
 	/* This had damn well better be true! */
 	if (map_len != 0) {
 		rv = __elfN(map_insert)(imgp, map, NULL, 0, map_addr,
 		    map_addr + map_len, prot, 0);
 		if (rv != KERN_SUCCESS)
 			return (EINVAL);
 	}
 
 	if (copy_len != 0) {
 		sf = vm_imgact_map_page(object, offset + filsz);
 		if (sf == NULL)
 			return (EIO);
 
 		/* send the page fragment to user space */
 		off = trunc_page_ps(offset + filsz, pagesize) -
 		    trunc_page(offset + filsz);
 		error = copyout((caddr_t)sf_buf_kva(sf) + off,
 		    (caddr_t)map_addr, copy_len);
 		vm_imgact_unmap_page(sf);
 		if (error != 0)
 			return (error);
 	}
 
 	/*
 	 * Remove write access to the page if it was only granted by map_insert
 	 * to allow copyout.
 	 */
 	if ((prot & VM_PROT_WRITE) == 0)
 		vm_map_protect(map, trunc_page(map_addr), round_page(map_addr +
 		    map_len), prot, FALSE);
 
 	return (0);
 }
 
 /*
  * Load the file "file" into memory.  It may be either a shared object
  * or an executable.
  *
  * The "addr" reference parameter is in/out.  On entry, it specifies
  * the address where a shared object should be loaded.  If the file is
  * an executable, this value is ignored.  On exit, "addr" specifies
  * where the file was actually loaded.
  *
  * The "entry" reference parameter is out only.  On exit, it specifies
  * the entry point for the loaded file.
  */
 static int
 __elfN(load_file)(struct proc *p, const char *file, u_long *addr,
 	u_long *entry, size_t pagesize)
 {
 	struct {
 		struct nameidata nd;
 		struct vattr attr;
 		struct image_params image_params;
 	} *tempdata;
 	const Elf_Ehdr *hdr = NULL;
 	const Elf_Phdr *phdr = NULL;
 	struct nameidata *nd;
 	struct vattr *attr;
 	struct image_params *imgp;
 	vm_prot_t prot;
 	u_long rbase;
 	u_long base_addr = 0;
 	int error, i, numsegs;
 
 #ifdef CAPABILITY_MODE
 	/*
 	 * XXXJA: This check can go away once we are sufficiently confident
 	 * that the checks in namei() are correct.
 	 */
 	if (IN_CAPABILITY_MODE(curthread))
 		return (ECAPMODE);
 #endif
 
 	tempdata = malloc(sizeof(*tempdata), M_TEMP, M_WAITOK);
 	nd = &tempdata->nd;
 	attr = &tempdata->attr;
 	imgp = &tempdata->image_params;
 
 	/*
 	 * Initialize part of the common data
 	 */
 	imgp->proc = p;
 	imgp->attr = attr;
 	imgp->firstpage = NULL;
 	imgp->image_header = NULL;
 	imgp->object = NULL;
 	imgp->execlabel = NULL;
 
 	NDINIT(nd, LOOKUP, LOCKLEAF | FOLLOW, UIO_SYSSPACE, file, curthread);
 	if ((error = namei(nd)) != 0) {
 		nd->ni_vp = NULL;
 		goto fail;
 	}
 	NDFREE(nd, NDF_ONLY_PNBUF);
 	imgp->vp = nd->ni_vp;
 
 	/*
 	 * Check permissions, modes, uid, etc on the file, and "open" it.
 	 */
 	error = exec_check_permissions(imgp);
 	if (error)
 		goto fail;
 
 	error = exec_map_first_page(imgp);
 	if (error)
 		goto fail;
 
 	/*
 	 * Also make certain that the interpreter stays the same, so set
 	 * its VV_TEXT flag, too.
 	 */
 	VOP_SET_TEXT(nd->ni_vp);
 
 	imgp->object = nd->ni_vp->v_object;
 
 	hdr = (const Elf_Ehdr *)imgp->image_header;
 	if ((error = __elfN(check_header)(hdr)) != 0)
 		goto fail;
 	if (hdr->e_type == ET_DYN)
 		rbase = *addr;
 	else if (hdr->e_type == ET_EXEC)
 		rbase = 0;
 	else {
 		error = ENOEXEC;
 		goto fail;
 	}
 
 	/* Only support headers that fit within first page for now      */
 	if ((hdr->e_phoff > PAGE_SIZE) ||
 	    (u_int)hdr->e_phentsize * hdr->e_phnum > PAGE_SIZE - hdr->e_phoff) {
 		error = ENOEXEC;
 		goto fail;
 	}
 
 	phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff);
 	if (!aligned(phdr, Elf_Addr)) {
 		error = ENOEXEC;
 		goto fail;
 	}
 
 	for (i = 0, numsegs = 0; i < hdr->e_phnum; i++) {
 		if (phdr[i].p_type == PT_LOAD && phdr[i].p_memsz != 0) {
 			/* Loadable segment */
 			prot = __elfN(trans_prot)(phdr[i].p_flags);
 			error = __elfN(load_section)(imgp, phdr[i].p_offset,
 			    (caddr_t)(uintptr_t)phdr[i].p_vaddr + rbase,
 			    phdr[i].p_memsz, phdr[i].p_filesz, prot, pagesize);
 			if (error != 0)
 				goto fail;
 			/*
 			 * Establish the base address if this is the
 			 * first segment.
 			 */
 			if (numsegs == 0)
   				base_addr = trunc_page(phdr[i].p_vaddr +
 				    rbase);
 			numsegs++;
 		}
 	}
 	*addr = base_addr;
 	*entry = (unsigned long)hdr->e_entry + rbase;
 
 fail:
 	if (imgp->firstpage)
 		exec_unmap_first_page(imgp);
 
 	if (nd->ni_vp)
 		vput(nd->ni_vp);
 
 	free(tempdata, M_TEMP);
 
 	return (error);
 }
 
 static int
 __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp)
 {
 	struct thread *td;
 	const Elf_Ehdr *hdr;
 	const Elf_Phdr *phdr;
 	Elf_Auxargs *elf_auxargs;
 	struct vmspace *vmspace;
 	const char *err_str, *newinterp;
 	char *interp, *interp_buf, *path;
 	Elf_Brandinfo *brand_info;
 	struct sysentvec *sv;
 	vm_prot_t prot;
 	u_long text_size, data_size, total_size, text_addr, data_addr;
 	u_long seg_size, seg_addr, addr, baddr, et_dyn_addr, entry, proghdr;
 	int32_t osrel;
 	int error, i, n, interp_name_len, have_interp;
 
 	hdr = (const Elf_Ehdr *)imgp->image_header;
 
 	/*
 	 * Do we have a valid ELF header ?
 	 *
 	 * Only allow ET_EXEC & ET_DYN here, reject ET_DYN later
 	 * if particular brand doesn't support it.
 	 */
 	if (__elfN(check_header)(hdr) != 0 ||
 	    (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN))
 		return (-1);
 
 	/*
 	 * From here on down, we return an errno, not -1, as we've
 	 * detected an ELF file.
 	 */
 
 	if ((hdr->e_phoff > PAGE_SIZE) ||
 	    (u_int)hdr->e_phentsize * hdr->e_phnum > PAGE_SIZE - hdr->e_phoff) {
 		/* Only support headers in first page for now */
 		uprintf("Program headers not in the first page\n");
 		return (ENOEXEC);
 	}
 	phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff); 
 	if (!aligned(phdr, Elf_Addr)) {
 		uprintf("Unaligned program headers\n");
 		return (ENOEXEC);
 	}
 
 	n = error = 0;
 	baddr = 0;
 	osrel = 0;
 	text_size = data_size = total_size = text_addr = data_addr = 0;
 	entry = proghdr = 0;
 	interp_name_len = 0;
 	err_str = newinterp = NULL;
 	interp = interp_buf = NULL;
 	td = curthread;
 
 	for (i = 0; i < hdr->e_phnum; i++) {
 		switch (phdr[i].p_type) {
 		case PT_LOAD:
 			if (n == 0)
 				baddr = phdr[i].p_vaddr;
 			n++;
 			break;
 		case PT_INTERP:
 			/* Path to interpreter */
 			if (phdr[i].p_filesz > MAXPATHLEN) {
 				uprintf("Invalid PT_INTERP\n");
 				error = ENOEXEC;
 				goto ret;
 			}
 			if (interp != NULL) {
 				uprintf("Multiple PT_INTERP headers\n");
 				error = ENOEXEC;
 				goto ret;
 			}
 			interp_name_len = phdr[i].p_filesz;
 			if (phdr[i].p_offset > PAGE_SIZE ||
 			    interp_name_len > PAGE_SIZE - phdr[i].p_offset) {
 				VOP_UNLOCK(imgp->vp, 0);
 				interp_buf = malloc(interp_name_len + 1, M_TEMP,
 				    M_WAITOK);
 				vn_lock(imgp->vp, LK_EXCLUSIVE | LK_RETRY);
 				error = vn_rdwr(UIO_READ, imgp->vp, interp_buf,
 				    interp_name_len, phdr[i].p_offset,
 				    UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred,
 				    NOCRED, NULL, td);
 				if (error != 0) {
 					uprintf("i/o error PT_INTERP\n");
 					goto ret;
 				}
 				interp_buf[interp_name_len] = '\0';
 				interp = interp_buf;
 			} else {
 				interp = __DECONST(char *, imgp->image_header) +
 				    phdr[i].p_offset;
 			}
 			break;
 		case PT_GNU_STACK:
 			if (__elfN(nxstack))
 				imgp->stack_prot =
 				    __elfN(trans_prot)(phdr[i].p_flags);
 			imgp->stack_sz = phdr[i].p_memsz;
 			break;
 		}
 	}
 
 	brand_info = __elfN(get_brandinfo)(imgp, interp, interp_name_len,
 	    &osrel);
 	if (brand_info == NULL) {
 		uprintf("ELF binary type \"%u\" not known.\n",
 		    hdr->e_ident[EI_OSABI]);
 		error = ENOEXEC;
 		goto ret;
 	}
 	et_dyn_addr = 0;
 	if (hdr->e_type == ET_DYN) {
 		if ((brand_info->flags & BI_CAN_EXEC_DYN) == 0) {
 			uprintf("Cannot execute shared object\n");
 			error = ENOEXEC;
 			goto ret;
 		}
 		/*
 		 * Honour the base load address from the dso if it is
 		 * non-zero for some reason.
 		 */
 		if (baddr == 0)
 			et_dyn_addr = ET_DYN_LOAD_ADDR;
 	}
 	sv = brand_info->sysvec;
 	if (interp != NULL && brand_info->interp_newpath != NULL)
 		newinterp = brand_info->interp_newpath;
 
 	/*
 	 * Avoid a possible deadlock if the current address space is destroyed
 	 * and that address space maps the locked vnode.  In the common case,
 	 * the locked vnode's v_usecount is decremented but remains greater
 	 * than zero.  Consequently, the vnode lock is not needed by vrele().
 	 * However, in cases where the vnode lock is external, such as nullfs,
 	 * v_usecount may become zero.
 	 *
 	 * The VV_TEXT flag prevents modifications to the executable while
 	 * the vnode is unlocked.
 	 */
 	VOP_UNLOCK(imgp->vp, 0);
 
 	error = exec_new_vmspace(imgp, sv);
 	imgp->proc->p_sysent = sv;
 
 	vn_lock(imgp->vp, LK_EXCLUSIVE | LK_RETRY);
 	if (error != 0)
 		goto ret;
 
 	for (i = 0; i < hdr->e_phnum; i++) {
 		switch (phdr[i].p_type) {
 		case PT_LOAD:	/* Loadable segment */
 			if (phdr[i].p_memsz == 0)
 				break;
 			prot = __elfN(trans_prot)(phdr[i].p_flags);
 			error = __elfN(load_section)(imgp, phdr[i].p_offset,
 			    (caddr_t)(uintptr_t)phdr[i].p_vaddr + et_dyn_addr,
 			    phdr[i].p_memsz, phdr[i].p_filesz, prot,
 			    sv->sv_pagesize);
 			if (error != 0)
 				goto ret;
 
 			/*
 			 * If this segment contains the program headers,
 			 * remember their virtual address for the AT_PHDR
 			 * aux entry. Static binaries don't usually include
 			 * a PT_PHDR entry.
 			 */
 			if (phdr[i].p_offset == 0 &&
 			    hdr->e_phoff + hdr->e_phnum * hdr->e_phentsize
 				<= phdr[i].p_filesz)
 				proghdr = phdr[i].p_vaddr + hdr->e_phoff +
 				    et_dyn_addr;
 
 			seg_addr = trunc_page(phdr[i].p_vaddr + et_dyn_addr);
 			seg_size = round_page(phdr[i].p_memsz +
 			    phdr[i].p_vaddr + et_dyn_addr - seg_addr);
 
 			/*
 			 * Make the largest executable segment the official
 			 * text segment and all others data.
 			 *
 			 * Note that obreak() assumes that data_addr + 
 			 * data_size == end of data load area, and the ELF
 			 * file format expects segments to be sorted by
 			 * address.  If multiple data segments exist, the
 			 * last one will be used.
 			 */
 
 			if (phdr[i].p_flags & PF_X && text_size < seg_size) {
 				text_size = seg_size;
 				text_addr = seg_addr;
 			} else {
 				data_size = seg_size;
 				data_addr = seg_addr;
 			}
 			total_size += seg_size;
 			break;
 		case PT_PHDR: 	/* Program header table info */
 			proghdr = phdr[i].p_vaddr + et_dyn_addr;
 			break;
 		default:
 			break;
 		}
 	}
 	
 	if (data_addr == 0 && data_size == 0) {
 		data_addr = text_addr;
 		data_size = text_size;
 	}
 
 	entry = (u_long)hdr->e_entry + et_dyn_addr;
 
 	/*
 	 * Check limits.  It should be safe to check the
 	 * limits after loading the segments since we do
 	 * not actually fault in all the segments pages.
 	 */
 	PROC_LOCK(imgp->proc);
 	if (data_size > lim_cur_proc(imgp->proc, RLIMIT_DATA))
 		err_str = "Data segment size exceeds process limit";
 	else if (text_size > maxtsiz)
 		err_str = "Text segment size exceeds system limit";
 	else if (total_size > lim_cur_proc(imgp->proc, RLIMIT_VMEM))
 		err_str = "Total segment size exceeds process limit";
 	else if (racct_set(imgp->proc, RACCT_DATA, data_size) != 0)
 		err_str = "Data segment size exceeds resource limit";
 	else if (racct_set(imgp->proc, RACCT_VMEM, total_size) != 0)
 		err_str = "Total segment size exceeds resource limit";
 	if (err_str != NULL) {
 		PROC_UNLOCK(imgp->proc);
 		uprintf("%s\n", err_str);
 		error = ENOMEM;
 		goto ret;
 	}
 
 	vmspace = imgp->proc->p_vmspace;
 	vmspace->vm_tsize = text_size >> PAGE_SHIFT;
 	vmspace->vm_taddr = (caddr_t)(uintptr_t)text_addr;
 	vmspace->vm_dsize = data_size >> PAGE_SHIFT;
 	vmspace->vm_daddr = (caddr_t)(uintptr_t)data_addr;
 
 	/*
 	 * We load the dynamic linker where a userland call
 	 * to mmap(0, ...) would put it.  The rationale behind this
 	 * calculation is that it leaves room for the heap to grow to
 	 * its maximum allowed size.
 	 */
 	addr = round_page((vm_offset_t)vmspace->vm_daddr + lim_max(td,
 	    RLIMIT_DATA));
 	PROC_UNLOCK(imgp->proc);
 
 	imgp->entry_addr = entry;
 
 	if (interp != NULL) {
 		have_interp = FALSE;
 		VOP_UNLOCK(imgp->vp, 0);
 		if (brand_info->emul_path != NULL &&
 		    brand_info->emul_path[0] != '\0') {
 			path = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
 			snprintf(path, MAXPATHLEN, "%s%s",
 			    brand_info->emul_path, interp);
 			error = __elfN(load_file)(imgp->proc, path, &addr,
 			    &imgp->entry_addr, sv->sv_pagesize);
 			free(path, M_TEMP);
 			if (error == 0)
 				have_interp = TRUE;
 		}
 		if (!have_interp && newinterp != NULL &&
 		    (brand_info->interp_path == NULL ||
 		    strcmp(interp, brand_info->interp_path) == 0)) {
 			error = __elfN(load_file)(imgp->proc, newinterp, &addr,
 			    &imgp->entry_addr, sv->sv_pagesize);
 			if (error == 0)
 				have_interp = TRUE;
 		}
 		if (!have_interp) {
 			error = __elfN(load_file)(imgp->proc, interp, &addr,
 			    &imgp->entry_addr, sv->sv_pagesize);
 		}
 		vn_lock(imgp->vp, LK_EXCLUSIVE | LK_RETRY);
 		if (error != 0) {
 			uprintf("ELF interpreter %s not found, error %d\n",
 			    interp, error);
 			goto ret;
 		}
 	} else
 		addr = et_dyn_addr;
 
 	/*
 	 * Construct auxargs table (used by the fixup routine)
 	 */
 	elf_auxargs = malloc(sizeof(Elf_Auxargs), M_TEMP, M_WAITOK);
 	elf_auxargs->execfd = -1;
 	elf_auxargs->phdr = proghdr;
 	elf_auxargs->phent = hdr->e_phentsize;
 	elf_auxargs->phnum = hdr->e_phnum;
 	elf_auxargs->pagesz = PAGE_SIZE;
 	elf_auxargs->base = addr;
 	elf_auxargs->flags = 0;
 	elf_auxargs->entry = entry;
 	elf_auxargs->hdr_eflags = hdr->e_flags;
 
 	imgp->auxargs = elf_auxargs;
 	imgp->interpreted = 0;
 	imgp->reloc_base = addr;
 	imgp->proc->p_osrel = osrel;
 	imgp->proc->p_elf_machine = hdr->e_machine;
 	imgp->proc->p_elf_flags = hdr->e_flags;
 
 ret:
 	free(interp_buf, M_TEMP);
 	return (error);
 }
 
 #define	suword __CONCAT(suword, __ELF_WORD_SIZE)
 
 int
 __elfN(freebsd_fixup)(register_t **stack_base, struct image_params *imgp)
 {
 	Elf_Auxargs *args = (Elf_Auxargs *)imgp->auxargs;
 	Elf_Addr *base;
 	Elf_Addr *pos;
 
 	base = (Elf_Addr *)*stack_base;
 	pos = base + (imgp->args->argc + imgp->args->envc + 2);
 
 	if (args->execfd != -1)
 		AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd);
 	AUXARGS_ENTRY(pos, AT_PHDR, args->phdr);
 	AUXARGS_ENTRY(pos, AT_PHENT, args->phent);
 	AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum);
 	AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz);
 	AUXARGS_ENTRY(pos, AT_FLAGS, args->flags);
 	AUXARGS_ENTRY(pos, AT_ENTRY, args->entry);
 	AUXARGS_ENTRY(pos, AT_BASE, args->base);
 #ifdef AT_EHDRFLAGS
 	AUXARGS_ENTRY(pos, AT_EHDRFLAGS, args->hdr_eflags);
 #endif
 	if (imgp->execpathp != 0)
 		AUXARGS_ENTRY(pos, AT_EXECPATH, imgp->execpathp);
 	AUXARGS_ENTRY(pos, AT_OSRELDATE,
 	    imgp->proc->p_ucred->cr_prison->pr_osreldate);
 	if (imgp->canary != 0) {
 		AUXARGS_ENTRY(pos, AT_CANARY, imgp->canary);
 		AUXARGS_ENTRY(pos, AT_CANARYLEN, imgp->canarylen);
 	}
 	AUXARGS_ENTRY(pos, AT_NCPUS, mp_ncpus);
 	if (imgp->pagesizes != 0) {
 		AUXARGS_ENTRY(pos, AT_PAGESIZES, imgp->pagesizes);
 		AUXARGS_ENTRY(pos, AT_PAGESIZESLEN, imgp->pagesizeslen);
 	}
 	if (imgp->sysent->sv_timekeep_base != 0) {
 		AUXARGS_ENTRY(pos, AT_TIMEKEEP,
 		    imgp->sysent->sv_timekeep_base);
 	}
 	AUXARGS_ENTRY(pos, AT_STACKPROT, imgp->sysent->sv_shared_page_obj
 	    != NULL && imgp->stack_prot != 0 ? imgp->stack_prot :
 	    imgp->sysent->sv_stackprot);
 	AUXARGS_ENTRY(pos, AT_NULL, 0);
 
 	free(imgp->auxargs, M_TEMP);
 	imgp->auxargs = NULL;
 
 	base--;
 	suword(base, (long)imgp->args->argc);
 	*stack_base = (register_t *)base;
 	return (0);
 }
 
 /*
  * Code for generating ELF core dumps.
  */
 
 typedef void (*segment_callback)(vm_map_entry_t, void *);
 
 /* Closure for cb_put_phdr(). */
 struct phdr_closure {
 	Elf_Phdr *phdr;		/* Program header to fill in */
 	Elf_Off offset;		/* Offset of segment in core file */
 };
 
 /* Closure for cb_size_segment(). */
 struct sseg_closure {
 	int count;		/* Count of writable segments. */
 	size_t size;		/* Total size of all writable segments. */
 };
 
 typedef void (*outfunc_t)(void *, struct sbuf *, size_t *);
 
 struct note_info {
 	int		type;		/* Note type. */
 	outfunc_t 	outfunc; 	/* Output function. */
 	void		*outarg;	/* Argument for the output function. */
 	size_t		outsize;	/* Output size. */
 	TAILQ_ENTRY(note_info) link;	/* Link to the next note info. */
 };
 
 TAILQ_HEAD(note_info_list, note_info);
 
 /* Coredump output parameters. */
 struct coredump_params {
 	off_t		offset;
 	struct ucred	*active_cred;
 	struct ucred	*file_cred;
 	struct thread	*td;
 	struct vnode	*vp;
 	struct gzio_stream *gzs;
 };
 
 static void cb_put_phdr(vm_map_entry_t, void *);
 static void cb_size_segment(vm_map_entry_t, void *);
 static int core_write(struct coredump_params *, const void *, size_t, off_t,
     enum uio_seg);
 static void each_dumpable_segment(struct thread *, segment_callback, void *);
 static int __elfN(corehdr)(struct coredump_params *, int, void *, size_t,
     struct note_info_list *, size_t);
 static void __elfN(prepare_notes)(struct thread *, struct note_info_list *,
     size_t *);
 static void __elfN(puthdr)(struct thread *, void *, size_t, int, size_t);
 static void __elfN(putnote)(struct note_info *, struct sbuf *);
 static size_t register_note(struct note_info_list *, int, outfunc_t, void *);
 static int sbuf_drain_core_output(void *, const char *, int);
 static int sbuf_drain_count(void *arg, const char *data, int len);
 
 static void __elfN(note_fpregset)(void *, struct sbuf *, size_t *);
 static void __elfN(note_prpsinfo)(void *, struct sbuf *, size_t *);
 static void __elfN(note_prstatus)(void *, struct sbuf *, size_t *);
 static void __elfN(note_threadmd)(void *, struct sbuf *, size_t *);
 static void __elfN(note_thrmisc)(void *, struct sbuf *, size_t *);
 static void __elfN(note_procstat_auxv)(void *, struct sbuf *, size_t *);
 static void __elfN(note_procstat_proc)(void *, struct sbuf *, size_t *);
 static void __elfN(note_procstat_psstrings)(void *, struct sbuf *, size_t *);
 static void note_procstat_files(void *, struct sbuf *, size_t *);
 static void note_procstat_groups(void *, struct sbuf *, size_t *);
 static void note_procstat_osrel(void *, struct sbuf *, size_t *);
 static void note_procstat_rlimit(void *, struct sbuf *, size_t *);
 static void note_procstat_umask(void *, struct sbuf *, size_t *);
 static void note_procstat_vmmap(void *, struct sbuf *, size_t *);
 
 #ifdef GZIO
 extern int compress_user_cores_gzlevel;
 
 /*
  * Write out a core segment to the compression stream.
  */
 static int
 compress_chunk(struct coredump_params *p, char *base, char *buf, u_int len)
 {
 	u_int chunk_len;
 	int error;
 
 	while (len > 0) {
 		chunk_len = MIN(len, CORE_BUF_SIZE);
 
 		/*
 		 * We can get EFAULT error here.
 		 * In that case zero out the current chunk of the segment.
 		 */
 		error = copyin(base, buf, chunk_len);
 		if (error != 0)
 			bzero(buf, chunk_len);
 		error = gzio_write(p->gzs, buf, chunk_len);
 		if (error != 0)
 			break;
 		base += chunk_len;
 		len -= chunk_len;
 	}
 	return (error);
 }
 
 static int
 core_gz_write(void *base, size_t len, off_t offset, void *arg)
 {
 
 	return (core_write((struct coredump_params *)arg, base, len, offset,
 	    UIO_SYSSPACE));
 }
 #endif /* GZIO */
 
 static int
 core_write(struct coredump_params *p, const void *base, size_t len,
     off_t offset, enum uio_seg seg)
 {
 
 	return (vn_rdwr_inchunks(UIO_WRITE, p->vp, __DECONST(void *, base),
 	    len, offset, seg, IO_UNIT | IO_DIRECT | IO_RANGELOCKED,
 	    p->active_cred, p->file_cred, NULL, p->td));
 }
 
 static int
 core_output(void *base, size_t len, off_t offset, struct coredump_params *p,
     void *tmpbuf)
 {
 	int error;
 
 #ifdef GZIO
 	if (p->gzs != NULL)
 		return (compress_chunk(p, base, tmpbuf, len));
 #endif
 	/*
 	 * EFAULT is a non-fatal error that we can get, for example,
 	 * if the segment is backed by a file but extends beyond its
 	 * end.
 	 */
 	error = core_write(p, base, len, offset, UIO_USERSPACE);
 	if (error == EFAULT) {
 		log(LOG_WARNING, "Failed to fully fault in a core file segment "
 		    "at VA %p with size 0x%zx to be written at offset 0x%jx "
 		    "for process %s\n", base, len, offset, curproc->p_comm);
 
 		/*
 		 * Write a "real" zero byte at the end of the target region
 		 * in the case this is the last segment.
 		 * The intermediate space will be implicitly zero-filled.
 		 */
 		error = core_write(p, zero_region, 1, offset + len - 1,
 		    UIO_SYSSPACE);
 	}
 	return (error);
 }
 
 /*
  * Drain into a core file.
  */
 static int
 sbuf_drain_core_output(void *arg, const char *data, int len)
 {
 	struct coredump_params *p;
 	int error, locked;
 
 	p = (struct coredump_params *)arg;
 
 	/*
 	 * Some kern_proc out routines that print to this sbuf may
 	 * call us with the process lock held. Draining with the
 	 * non-sleepable lock held is unsafe. The lock is needed for
 	 * those routines when dumping a live process. In our case we
 	 * can safely release the lock before draining and acquire
 	 * again after.
 	 */
 	locked = PROC_LOCKED(p->td->td_proc);
 	if (locked)
 		PROC_UNLOCK(p->td->td_proc);
 #ifdef GZIO
 	if (p->gzs != NULL)
 		error = gzio_write(p->gzs, __DECONST(char *, data), len);
 	else
 #endif
 		error = core_write(p, __DECONST(void *, data), len, p->offset,
 		    UIO_SYSSPACE);
 	if (locked)
 		PROC_LOCK(p->td->td_proc);
 	if (error != 0)
 		return (-error);
 	p->offset += len;
 	return (len);
 }
 
 /*
  * Drain into a counter.
  */
 static int
 sbuf_drain_count(void *arg, const char *data __unused, int len)
 {
 	size_t *sizep;
 
 	sizep = (size_t *)arg;
 	*sizep += len;
 	return (len);
 }
 
 int
 __elfN(coredump)(struct thread *td, struct vnode *vp, off_t limit, int flags)
 {
 	struct ucred *cred = td->td_ucred;
 	int error = 0;
 	struct sseg_closure seginfo;
 	struct note_info_list notelst;
 	struct coredump_params params;
 	struct note_info *ninfo;
 	void *hdr, *tmpbuf;
 	size_t hdrsize, notesz, coresize;
 #ifdef GZIO
 	boolean_t compress;
 
 	compress = (flags & IMGACT_CORE_COMPRESS) != 0;
 #endif
 	hdr = NULL;
 	tmpbuf = NULL;
 	TAILQ_INIT(&notelst);
 
 	/* Size the program segments. */
 	seginfo.count = 0;
 	seginfo.size = 0;
 	each_dumpable_segment(td, cb_size_segment, &seginfo);
 
 	/*
 	 * Collect info about the core file header area.
 	 */
 	hdrsize = sizeof(Elf_Ehdr) + sizeof(Elf_Phdr) * (1 + seginfo.count);
 	if (seginfo.count + 1 >= PN_XNUM)
 		hdrsize += sizeof(Elf_Shdr);
 	__elfN(prepare_notes)(td, &notelst, &notesz);
 	coresize = round_page(hdrsize + notesz) + seginfo.size;
 
 	/* Set up core dump parameters. */
 	params.offset = 0;
 	params.active_cred = cred;
 	params.file_cred = NOCRED;
 	params.td = td;
 	params.vp = vp;
 	params.gzs = NULL;
 
 #ifdef RACCT
 	if (racct_enable) {
 		PROC_LOCK(td->td_proc);
 		error = racct_add(td->td_proc, RACCT_CORE, coresize);
 		PROC_UNLOCK(td->td_proc);
 		if (error != 0) {
 			error = EFAULT;
 			goto done;
 		}
 	}
 #endif
 	if (coresize >= limit) {
 		error = EFAULT;
 		goto done;
 	}
 
 #ifdef GZIO
 	/* Create a compression stream if necessary. */
 	if (compress) {
 		params.gzs = gzio_init(core_gz_write, GZIO_DEFLATE,
 		    CORE_BUF_SIZE, compress_user_cores_gzlevel, &params);
 		if (params.gzs == NULL) {
 			error = EFAULT;
 			goto done;
 		}
 		tmpbuf = malloc(CORE_BUF_SIZE, M_TEMP, M_WAITOK | M_ZERO);
         }
 #endif
 
 	/*
 	 * Allocate memory for building the header, fill it up,
 	 * and write it out following the notes.
 	 */
 	hdr = malloc(hdrsize, M_TEMP, M_WAITOK);
 	error = __elfN(corehdr)(&params, seginfo.count, hdr, hdrsize, &notelst,
 	    notesz);
 
 	/* Write the contents of all of the writable segments. */
 	if (error == 0) {
 		Elf_Phdr *php;
 		off_t offset;
 		int i;
 
 		php = (Elf_Phdr *)((char *)hdr + sizeof(Elf_Ehdr)) + 1;
 		offset = round_page(hdrsize + notesz);
 		for (i = 0; i < seginfo.count; i++) {
 			error = core_output((caddr_t)(uintptr_t)php->p_vaddr,
 			    php->p_filesz, offset, &params, tmpbuf);
 			if (error != 0)
 				break;
 			offset += php->p_filesz;
 			php++;
 		}
 #ifdef GZIO
 		if (error == 0 && compress)
 			error = gzio_flush(params.gzs);
 #endif
 	}
 	if (error) {
 		log(LOG_WARNING,
 		    "Failed to write core file for process %s (error %d)\n",
 		    curproc->p_comm, error);
 	}
 
 done:
 #ifdef GZIO
 	if (compress) {
 		free(tmpbuf, M_TEMP);
 		if (params.gzs != NULL)
 			gzio_fini(params.gzs);
 	}
 #endif
 	while ((ninfo = TAILQ_FIRST(&notelst)) != NULL) {
 		TAILQ_REMOVE(&notelst, ninfo, link);
 		free(ninfo, M_TEMP);
 	}
 	if (hdr != NULL)
 		free(hdr, M_TEMP);
 
 	return (error);
 }
 
 /*
  * A callback for each_dumpable_segment() to write out the segment's
  * program header entry.
  */
 static void
 cb_put_phdr(entry, closure)
 	vm_map_entry_t entry;
 	void *closure;
 {
 	struct phdr_closure *phc = (struct phdr_closure *)closure;
 	Elf_Phdr *phdr = phc->phdr;
 
 	phc->offset = round_page(phc->offset);
 
 	phdr->p_type = PT_LOAD;
 	phdr->p_offset = phc->offset;
 	phdr->p_vaddr = entry->start;
 	phdr->p_paddr = 0;
 	phdr->p_filesz = phdr->p_memsz = entry->end - entry->start;
 	phdr->p_align = PAGE_SIZE;
 	phdr->p_flags = __elfN(untrans_prot)(entry->protection);
 
 	phc->offset += phdr->p_filesz;
 	phc->phdr++;
 }
 
 /*
  * A callback for each_dumpable_segment() to gather information about
  * the number of segments and their total size.
  */
 static void
 cb_size_segment(vm_map_entry_t entry, void *closure)
 {
 	struct sseg_closure *ssc = (struct sseg_closure *)closure;
 
 	ssc->count++;
 	ssc->size += entry->end - entry->start;
 }
 
 /*
  * For each writable segment in the process's memory map, call the given
  * function with a pointer to the map entry and some arbitrary
  * caller-supplied data.
  */
 static void
 each_dumpable_segment(struct thread *td, segment_callback func, void *closure)
 {
 	struct proc *p = td->td_proc;
 	vm_map_t map = &p->p_vmspace->vm_map;
 	vm_map_entry_t entry;
 	vm_object_t backing_object, object;
 	boolean_t ignore_entry;
 
 	vm_map_lock_read(map);
 	for (entry = map->header.next; entry != &map->header;
 	    entry = entry->next) {
 		/*
 		 * Don't dump inaccessible mappings, deal with legacy
 		 * coredump mode.
 		 *
 		 * Note that read-only segments related to the elf binary
 		 * are marked MAP_ENTRY_NOCOREDUMP now so we no longer
 		 * need to arbitrarily ignore such segments.
 		 */
 		if (elf_legacy_coredump) {
 			if ((entry->protection & VM_PROT_RW) != VM_PROT_RW)
 				continue;
 		} else {
 			if ((entry->protection & VM_PROT_ALL) == 0)
 				continue;
 		}
 
 		/*
 		 * Dont include memory segment in the coredump if
 		 * MAP_NOCORE is set in mmap(2) or MADV_NOCORE in
 		 * madvise(2).  Do not dump submaps (i.e. parts of the
 		 * kernel map).
 		 */
 		if (entry->eflags & (MAP_ENTRY_NOCOREDUMP|MAP_ENTRY_IS_SUB_MAP))
 			continue;
 
 		if ((object = entry->object.vm_object) == NULL)
 			continue;
 
 		/* Ignore memory-mapped devices and such things. */
 		VM_OBJECT_RLOCK(object);
 		while ((backing_object = object->backing_object) != NULL) {
 			VM_OBJECT_RLOCK(backing_object);
 			VM_OBJECT_RUNLOCK(object);
 			object = backing_object;
 		}
 		ignore_entry = object->type != OBJT_DEFAULT &&
 		    object->type != OBJT_SWAP && object->type != OBJT_VNODE &&
 		    object->type != OBJT_PHYS;
 		VM_OBJECT_RUNLOCK(object);
 		if (ignore_entry)
 			continue;
 
 		(*func)(entry, closure);
 	}
 	vm_map_unlock_read(map);
 }
 
 /*
  * Write the core file header to the file, including padding up to
  * the page boundary.
  */
 static int
 __elfN(corehdr)(struct coredump_params *p, int numsegs, void *hdr,
     size_t hdrsize, struct note_info_list *notelst, size_t notesz)
 {
 	struct note_info *ninfo;
 	struct sbuf *sb;
 	int error;
 
 	/* Fill in the header. */
 	bzero(hdr, hdrsize);
 	__elfN(puthdr)(p->td, hdr, hdrsize, numsegs, notesz);
 
 	sb = sbuf_new(NULL, NULL, CORE_BUF_SIZE, SBUF_FIXEDLEN);
 	sbuf_set_drain(sb, sbuf_drain_core_output, p);
 	sbuf_start_section(sb, NULL);
 	sbuf_bcat(sb, hdr, hdrsize);
 	TAILQ_FOREACH(ninfo, notelst, link)
 	    __elfN(putnote)(ninfo, sb);
 	/* Align up to a page boundary for the program segments. */
 	sbuf_end_section(sb, -1, PAGE_SIZE, 0);
 	error = sbuf_finish(sb);
 	sbuf_delete(sb);
 
 	return (error);
 }
 
 static void
 __elfN(prepare_notes)(struct thread *td, struct note_info_list *list,
     size_t *sizep)
 {
 	struct proc *p;
 	struct thread *thr;
 	size_t size;
 
 	p = td->td_proc;
 	size = 0;
 
 	size += register_note(list, NT_PRPSINFO, __elfN(note_prpsinfo), p);
 
 	/*
 	 * To have the debugger select the right thread (LWP) as the initial
 	 * thread, we dump the state of the thread passed to us in td first.
 	 * This is the thread that causes the core dump and thus likely to
 	 * be the right thread one wants to have selected in the debugger.
 	 */
 	thr = td;
 	while (thr != NULL) {
 		size += register_note(list, NT_PRSTATUS,
 		    __elfN(note_prstatus), thr);
 		size += register_note(list, NT_FPREGSET,
 		    __elfN(note_fpregset), thr);
 		size += register_note(list, NT_THRMISC,
 		    __elfN(note_thrmisc), thr);
 		size += register_note(list, -1,
 		    __elfN(note_threadmd), thr);
 
 		thr = (thr == td) ? TAILQ_FIRST(&p->p_threads) :
 		    TAILQ_NEXT(thr, td_plist);
 		if (thr == td)
 			thr = TAILQ_NEXT(thr, td_plist);
 	}
 
 	size += register_note(list, NT_PROCSTAT_PROC,
 	    __elfN(note_procstat_proc), p);
 	size += register_note(list, NT_PROCSTAT_FILES,
 	    note_procstat_files, p);
 	size += register_note(list, NT_PROCSTAT_VMMAP,
 	    note_procstat_vmmap, p);
 	size += register_note(list, NT_PROCSTAT_GROUPS,
 	    note_procstat_groups, p);
 	size += register_note(list, NT_PROCSTAT_UMASK,
 	    note_procstat_umask, p);
 	size += register_note(list, NT_PROCSTAT_RLIMIT,
 	    note_procstat_rlimit, p);
 	size += register_note(list, NT_PROCSTAT_OSREL,
 	    note_procstat_osrel, p);
 	size += register_note(list, NT_PROCSTAT_PSSTRINGS,
 	    __elfN(note_procstat_psstrings), p);
 	size += register_note(list, NT_PROCSTAT_AUXV,
 	    __elfN(note_procstat_auxv), p);
 
 	*sizep = size;
 }
 
 static void
 __elfN(puthdr)(struct thread *td, void *hdr, size_t hdrsize, int numsegs,
     size_t notesz)
 {
 	Elf_Ehdr *ehdr;
 	Elf_Phdr *phdr;
 	Elf_Shdr *shdr;
 	struct phdr_closure phc;
 
 	ehdr = (Elf_Ehdr *)hdr;
 
 	ehdr->e_ident[EI_MAG0] = ELFMAG0;
 	ehdr->e_ident[EI_MAG1] = ELFMAG1;
 	ehdr->e_ident[EI_MAG2] = ELFMAG2;
 	ehdr->e_ident[EI_MAG3] = ELFMAG3;
 	ehdr->e_ident[EI_CLASS] = ELF_CLASS;
 	ehdr->e_ident[EI_DATA] = ELF_DATA;
 	ehdr->e_ident[EI_VERSION] = EV_CURRENT;
 	ehdr->e_ident[EI_OSABI] = ELFOSABI_FREEBSD;
 	ehdr->e_ident[EI_ABIVERSION] = 0;
 	ehdr->e_ident[EI_PAD] = 0;
 	ehdr->e_type = ET_CORE;
 	ehdr->e_machine = td->td_proc->p_elf_machine;
 	ehdr->e_version = EV_CURRENT;
 	ehdr->e_entry = 0;
 	ehdr->e_phoff = sizeof(Elf_Ehdr);
 	ehdr->e_flags = td->td_proc->p_elf_flags;
 	ehdr->e_ehsize = sizeof(Elf_Ehdr);
 	ehdr->e_phentsize = sizeof(Elf_Phdr);
 	ehdr->e_shentsize = sizeof(Elf_Shdr);
 	ehdr->e_shstrndx = SHN_UNDEF;
 	if (numsegs + 1 < PN_XNUM) {
 		ehdr->e_phnum = numsegs + 1;
 		ehdr->e_shnum = 0;
 	} else {
 		ehdr->e_phnum = PN_XNUM;
 		ehdr->e_shnum = 1;
 
 		ehdr->e_shoff = ehdr->e_phoff +
 		    (numsegs + 1) * ehdr->e_phentsize;
 		KASSERT(ehdr->e_shoff == hdrsize - sizeof(Elf_Shdr),
 		    ("e_shoff: %zu, hdrsize - shdr: %zu",
 		     (size_t)ehdr->e_shoff, hdrsize - sizeof(Elf_Shdr)));
 
 		shdr = (Elf_Shdr *)((char *)hdr + ehdr->e_shoff);
 		memset(shdr, 0, sizeof(*shdr));
 		/*
 		 * A special first section is used to hold large segment and
 		 * section counts.  This was proposed by Sun Microsystems in
 		 * Solaris and has been adopted by Linux; the standard ELF
 		 * tools are already familiar with the technique.
 		 *
 		 * See table 7-7 of the Solaris "Linker and Libraries Guide"
 		 * (or 12-7 depending on the version of the document) for more
 		 * details.
 		 */
 		shdr->sh_type = SHT_NULL;
 		shdr->sh_size = ehdr->e_shnum;
 		shdr->sh_link = ehdr->e_shstrndx;
 		shdr->sh_info = numsegs + 1;
 	}
 
 	/*
 	 * Fill in the program header entries.
 	 */
 	phdr = (Elf_Phdr *)((char *)hdr + ehdr->e_phoff);
 
 	/* The note segement. */
 	phdr->p_type = PT_NOTE;
 	phdr->p_offset = hdrsize;
 	phdr->p_vaddr = 0;
 	phdr->p_paddr = 0;
 	phdr->p_filesz = notesz;
 	phdr->p_memsz = 0;
 	phdr->p_flags = PF_R;
 	phdr->p_align = ELF_NOTE_ROUNDSIZE;
 	phdr++;
 
 	/* All the writable segments from the program. */
 	phc.phdr = phdr;
 	phc.offset = round_page(hdrsize + notesz);
 	each_dumpable_segment(td, cb_put_phdr, &phc);
 }
 
 static size_t
 register_note(struct note_info_list *list, int type, outfunc_t out, void *arg)
 {
 	struct note_info *ninfo;
 	size_t size, notesize;
 
 	size = 0;
 	out(arg, NULL, &size);
 	ninfo = malloc(sizeof(*ninfo), M_TEMP, M_ZERO | M_WAITOK);
 	ninfo->type = type;
 	ninfo->outfunc = out;
 	ninfo->outarg = arg;
 	ninfo->outsize = size;
 	TAILQ_INSERT_TAIL(list, ninfo, link);
 
 	if (type == -1)
 		return (size);
 
 	notesize = sizeof(Elf_Note) +		/* note header */
 	    roundup2(sizeof(FREEBSD_ABI_VENDOR), ELF_NOTE_ROUNDSIZE) +
 						/* note name */
 	    roundup2(size, ELF_NOTE_ROUNDSIZE);	/* note description */
 
 	return (notesize);
 }
 
 static size_t
 append_note_data(const void *src, void *dst, size_t len)
 {
 	size_t padded_len;
 
 	padded_len = roundup2(len, ELF_NOTE_ROUNDSIZE);
 	if (dst != NULL) {
 		bcopy(src, dst, len);
 		bzero((char *)dst + len, padded_len - len);
 	}
 	return (padded_len);
 }
 
 size_t
 __elfN(populate_note)(int type, void *src, void *dst, size_t size, void **descp)
 {
 	Elf_Note *note;
 	char *buf;
 	size_t notesize;
 
 	buf = dst;
 	if (buf != NULL) {
 		note = (Elf_Note *)buf;
 		note->n_namesz = sizeof(FREEBSD_ABI_VENDOR);
 		note->n_descsz = size;
 		note->n_type = type;
 		buf += sizeof(*note);
 		buf += append_note_data(FREEBSD_ABI_VENDOR, buf,
 		    sizeof(FREEBSD_ABI_VENDOR));
 		append_note_data(src, buf, size);
 		if (descp != NULL)
 			*descp = buf;
 	}
 
 	notesize = sizeof(Elf_Note) +		/* note header */
 	    roundup2(sizeof(FREEBSD_ABI_VENDOR), ELF_NOTE_ROUNDSIZE) +
 						/* note name */
 	    roundup2(size, ELF_NOTE_ROUNDSIZE);	/* note description */
 
 	return (notesize);
 }
 
 static void
 __elfN(putnote)(struct note_info *ninfo, struct sbuf *sb)
 {
 	Elf_Note note;
 	ssize_t old_len, sect_len;
 	size_t new_len, descsz, i;
 
 	if (ninfo->type == -1) {
 		ninfo->outfunc(ninfo->outarg, sb, &ninfo->outsize);
 		return;
 	}
 
 	note.n_namesz = sizeof(FREEBSD_ABI_VENDOR);
 	note.n_descsz = ninfo->outsize;
 	note.n_type = ninfo->type;
 
 	sbuf_bcat(sb, &note, sizeof(note));
 	sbuf_start_section(sb, &old_len);
 	sbuf_bcat(sb, FREEBSD_ABI_VENDOR, sizeof(FREEBSD_ABI_VENDOR));
 	sbuf_end_section(sb, old_len, ELF_NOTE_ROUNDSIZE, 0);
 	if (note.n_descsz == 0)
 		return;
 	sbuf_start_section(sb, &old_len);
 	ninfo->outfunc(ninfo->outarg, sb, &ninfo->outsize);
 	sect_len = sbuf_end_section(sb, old_len, ELF_NOTE_ROUNDSIZE, 0);
 	if (sect_len < 0)
 		return;
 
 	new_len = (size_t)sect_len;
 	descsz = roundup(note.n_descsz, ELF_NOTE_ROUNDSIZE);
 	if (new_len < descsz) {
 		/*
 		 * It is expected that individual note emitters will correctly
 		 * predict their expected output size and fill up to that size
 		 * themselves, padding in a format-specific way if needed.
 		 * However, in case they don't, just do it here with zeros.
 		 */
 		for (i = 0; i < descsz - new_len; i++)
 			sbuf_putc(sb, 0);
 	} else if (new_len > descsz) {
 		/*
 		 * We can't always truncate sb -- we may have drained some
 		 * of it already.
 		 */
 		KASSERT(new_len == descsz, ("%s: Note type %u changed as we "
 		    "read it (%zu > %zu).  Since it is longer than "
 		    "expected, this coredump's notes are corrupt.  THIS "
 		    "IS A BUG in the note_procstat routine for type %u.\n",
 		    __func__, (unsigned)note.n_type, new_len, descsz,
 		    (unsigned)note.n_type));
 	}
 }
 
 /*
  * Miscellaneous note out functions.
  */
 
 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32
 #include <compat/freebsd32/freebsd32.h>
 
 typedef struct prstatus32 elf_prstatus_t;
 typedef struct prpsinfo32 elf_prpsinfo_t;
 typedef struct fpreg32 elf_prfpregset_t;
 typedef struct fpreg32 elf_fpregset_t;
 typedef struct reg32 elf_gregset_t;
 typedef struct thrmisc32 elf_thrmisc_t;
 #define ELF_KERN_PROC_MASK	KERN_PROC_MASK32
 typedef struct kinfo_proc32 elf_kinfo_proc_t;
 typedef uint32_t elf_ps_strings_t;
 #else
 typedef prstatus_t elf_prstatus_t;
 typedef prpsinfo_t elf_prpsinfo_t;
 typedef prfpregset_t elf_prfpregset_t;
 typedef prfpregset_t elf_fpregset_t;
 typedef gregset_t elf_gregset_t;
 typedef thrmisc_t elf_thrmisc_t;
 #define ELF_KERN_PROC_MASK	0
 typedef struct kinfo_proc elf_kinfo_proc_t;
 typedef vm_offset_t elf_ps_strings_t;
 #endif
 
 static void
 __elfN(note_prpsinfo)(void *arg, struct sbuf *sb, size_t *sizep)
 {
 	struct sbuf sbarg;
 	size_t len;
 	char *cp, *end;
 	struct proc *p;
 	elf_prpsinfo_t *psinfo;
 	int error;
 
 	p = (struct proc *)arg;
 	if (sb != NULL) {
 		KASSERT(*sizep == sizeof(*psinfo), ("invalid size"));
 		psinfo = malloc(sizeof(*psinfo), M_TEMP, M_ZERO | M_WAITOK);
 		psinfo->pr_version = PRPSINFO_VERSION;
 		psinfo->pr_psinfosz = sizeof(elf_prpsinfo_t);
 		strlcpy(psinfo->pr_fname, p->p_comm, sizeof(psinfo->pr_fname));
 		PROC_LOCK(p);
 		if (p->p_args != NULL) {
 			len = sizeof(psinfo->pr_psargs) - 1;
 			if (len > p->p_args->ar_length)
 				len = p->p_args->ar_length;
 			memcpy(psinfo->pr_psargs, p->p_args->ar_args, len);
 			PROC_UNLOCK(p);
 			error = 0;
 		} else {
 			_PHOLD(p);
 			PROC_UNLOCK(p);
 			sbuf_new(&sbarg, psinfo->pr_psargs,
 			    sizeof(psinfo->pr_psargs), SBUF_FIXEDLEN);
 			error = proc_getargv(curthread, p, &sbarg);
 			PRELE(p);
 			if (sbuf_finish(&sbarg) == 0)
 				len = sbuf_len(&sbarg) - 1;
 			else
 				len = sizeof(psinfo->pr_psargs) - 1;
 			sbuf_delete(&sbarg);
 		}
 		if (error || len == 0)
 			strlcpy(psinfo->pr_psargs, p->p_comm,
 			    sizeof(psinfo->pr_psargs));
 		else {
 			KASSERT(len < sizeof(psinfo->pr_psargs),
 			    ("len is too long: %zu vs %zu", len,
 			    sizeof(psinfo->pr_psargs)));
 			cp = psinfo->pr_psargs;
 			end = cp + len - 1;
 			for (;;) {
 				cp = memchr(cp, '\0', end - cp);
 				if (cp == NULL)
 					break;
 				*cp = ' ';
 			}
 		}
 		psinfo->pr_pid = p->p_pid;
 		sbuf_bcat(sb, psinfo, sizeof(*psinfo));
 		free(psinfo, M_TEMP);
 	}
 	*sizep = sizeof(*psinfo);
 }
 
 static void
 __elfN(note_prstatus)(void *arg, struct sbuf *sb, size_t *sizep)
 {
 	struct thread *td;
 	elf_prstatus_t *status;
 
 	td = (struct thread *)arg;
 	if (sb != NULL) {
 		KASSERT(*sizep == sizeof(*status), ("invalid size"));
 		status = malloc(sizeof(*status), M_TEMP, M_ZERO | M_WAITOK);
 		status->pr_version = PRSTATUS_VERSION;
 		status->pr_statussz = sizeof(elf_prstatus_t);
 		status->pr_gregsetsz = sizeof(elf_gregset_t);
 		status->pr_fpregsetsz = sizeof(elf_fpregset_t);
 		status->pr_osreldate = osreldate;
 		status->pr_cursig = td->td_proc->p_sig;
 		status->pr_pid = td->td_tid;
 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32
 		fill_regs32(td, &status->pr_reg);
 #else
 		fill_regs(td, &status->pr_reg);
 #endif
 		sbuf_bcat(sb, status, sizeof(*status));
 		free(status, M_TEMP);
 	}
 	*sizep = sizeof(*status);
 }
 
 static void
 __elfN(note_fpregset)(void *arg, struct sbuf *sb, size_t *sizep)
 {
 	struct thread *td;
 	elf_prfpregset_t *fpregset;
 
 	td = (struct thread *)arg;
 	if (sb != NULL) {
 		KASSERT(*sizep == sizeof(*fpregset), ("invalid size"));
 		fpregset = malloc(sizeof(*fpregset), M_TEMP, M_ZERO | M_WAITOK);
 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32
 		fill_fpregs32(td, fpregset);
 #else
 		fill_fpregs(td, fpregset);
 #endif
 		sbuf_bcat(sb, fpregset, sizeof(*fpregset));
 		free(fpregset, M_TEMP);
 	}
 	*sizep = sizeof(*fpregset);
 }
 
 static void
 __elfN(note_thrmisc)(void *arg, struct sbuf *sb, size_t *sizep)
 {
 	struct thread *td;
 	elf_thrmisc_t thrmisc;
 
 	td = (struct thread *)arg;
 	if (sb != NULL) {
 		KASSERT(*sizep == sizeof(thrmisc), ("invalid size"));
 		bzero(&thrmisc._pad, sizeof(thrmisc._pad));
 		strcpy(thrmisc.pr_tname, td->td_name);
 		sbuf_bcat(sb, &thrmisc, sizeof(thrmisc));
 	}
 	*sizep = sizeof(thrmisc);
 }
 
 /*
  * Allow for MD specific notes, as well as any MD
  * specific preparations for writing MI notes.
  */
 static void
 __elfN(note_threadmd)(void *arg, struct sbuf *sb, size_t *sizep)
 {
 	struct thread *td;
 	void *buf;
 	size_t size;
 
 	td = (struct thread *)arg;
 	size = *sizep;
 	if (size != 0 && sb != NULL)
 		buf = malloc(size, M_TEMP, M_ZERO | M_WAITOK);
 	else
 		buf = NULL;
 	size = 0;
 	__elfN(dump_thread)(td, buf, &size);
 	KASSERT(sb == NULL || *sizep == size, ("invalid size"));
 	if (size != 0 && sb != NULL)
 		sbuf_bcat(sb, buf, size);
 	free(buf, M_TEMP);
 	*sizep = size;
 }
 
 #ifdef KINFO_PROC_SIZE
 CTASSERT(sizeof(struct kinfo_proc) == KINFO_PROC_SIZE);
 #endif
 
 static void
 __elfN(note_procstat_proc)(void *arg, struct sbuf *sb, size_t *sizep)
 {
 	struct proc *p;
 	size_t size;
 	int structsize;
 
 	p = (struct proc *)arg;
 	size = sizeof(structsize) + p->p_numthreads *
 	    sizeof(elf_kinfo_proc_t);
 
 	if (sb != NULL) {
 		KASSERT(*sizep == size, ("invalid size"));
 		structsize = sizeof(elf_kinfo_proc_t);
 		sbuf_bcat(sb, &structsize, sizeof(structsize));
 		sx_slock(&proctree_lock);
 		PROC_LOCK(p);
 		kern_proc_out(p, sb, ELF_KERN_PROC_MASK);
 		sx_sunlock(&proctree_lock);
 	}
 	*sizep = size;
 }
 
 #ifdef KINFO_FILE_SIZE
 CTASSERT(sizeof(struct kinfo_file) == KINFO_FILE_SIZE);
 #endif
 
 static void
 note_procstat_files(void *arg, struct sbuf *sb, size_t *sizep)
 {
 	struct proc *p;
 	size_t size, sect_sz, i;
 	ssize_t start_len, sect_len;
 	int structsize, filedesc_flags;
 
 	if (coredump_pack_fileinfo)
 		filedesc_flags = KERN_FILEDESC_PACK_KINFO;
 	else
 		filedesc_flags = 0;
 
 	p = (struct proc *)arg;
 	structsize = sizeof(struct kinfo_file);
 	if (sb == NULL) {
 		size = 0;
 		sb = sbuf_new(NULL, NULL, 128, SBUF_FIXEDLEN);
 		sbuf_set_drain(sb, sbuf_drain_count, &size);
 		sbuf_bcat(sb, &structsize, sizeof(structsize));
 		PROC_LOCK(p);
 		kern_proc_filedesc_out(p, sb, -1, filedesc_flags);
 		sbuf_finish(sb);
 		sbuf_delete(sb);
 		*sizep = size;
 	} else {
 		sbuf_start_section(sb, &start_len);
 
 		sbuf_bcat(sb, &structsize, sizeof(structsize));
 		PROC_LOCK(p);
 		kern_proc_filedesc_out(p, sb, *sizep - sizeof(structsize),
 		    filedesc_flags);
 
 		sect_len = sbuf_end_section(sb, start_len, 0, 0);
 		if (sect_len < 0)
 			return;
 		sect_sz = sect_len;
 
 		KASSERT(sect_sz <= *sizep,
 		    ("kern_proc_filedesc_out did not respect maxlen; "
 		     "requested %zu, got %zu", *sizep - sizeof(structsize),
 		     sect_sz - sizeof(structsize)));
 
 		for (i = 0; i < *sizep - sect_sz && sb->s_error == 0; i++)
 			sbuf_putc(sb, 0);
 	}
 }
 
 #ifdef KINFO_VMENTRY_SIZE
 CTASSERT(sizeof(struct kinfo_vmentry) == KINFO_VMENTRY_SIZE);
 #endif
 
 static void
 note_procstat_vmmap(void *arg, struct sbuf *sb, size_t *sizep)
 {
 	struct proc *p;
 	size_t size;
 	int structsize, vmmap_flags;
 
 	if (coredump_pack_vmmapinfo)
 		vmmap_flags = KERN_VMMAP_PACK_KINFO;
 	else
 		vmmap_flags = 0;
 
 	p = (struct proc *)arg;
 	structsize = sizeof(struct kinfo_vmentry);
 	if (sb == NULL) {
 		size = 0;
 		sb = sbuf_new(NULL, NULL, 128, SBUF_FIXEDLEN);
 		sbuf_set_drain(sb, sbuf_drain_count, &size);
 		sbuf_bcat(sb, &structsize, sizeof(structsize));
 		PROC_LOCK(p);
 		kern_proc_vmmap_out(p, sb, -1, vmmap_flags);
 		sbuf_finish(sb);
 		sbuf_delete(sb);
 		*sizep = size;
 	} else {
 		sbuf_bcat(sb, &structsize, sizeof(structsize));
 		PROC_LOCK(p);
 		kern_proc_vmmap_out(p, sb, *sizep - sizeof(structsize),
 		    vmmap_flags);
 	}
 }
 
 static void
 note_procstat_groups(void *arg, struct sbuf *sb, size_t *sizep)
 {
 	struct proc *p;
 	size_t size;
 	int structsize;
 
 	p = (struct proc *)arg;
 	size = sizeof(structsize) + p->p_ucred->cr_ngroups * sizeof(gid_t);
 	if (sb != NULL) {
 		KASSERT(*sizep == size, ("invalid size"));
 		structsize = sizeof(gid_t);
 		sbuf_bcat(sb, &structsize, sizeof(structsize));
 		sbuf_bcat(sb, p->p_ucred->cr_groups, p->p_ucred->cr_ngroups *
 		    sizeof(gid_t));
 	}
 	*sizep = size;
 }
 
 static void
 note_procstat_umask(void *arg, struct sbuf *sb, size_t *sizep)
 {
 	struct proc *p;
 	size_t size;
 	int structsize;
 
 	p = (struct proc *)arg;
 	size = sizeof(structsize) + sizeof(p->p_fd->fd_cmask);
 	if (sb != NULL) {
 		KASSERT(*sizep == size, ("invalid size"));
 		structsize = sizeof(p->p_fd->fd_cmask);
 		sbuf_bcat(sb, &structsize, sizeof(structsize));
 		sbuf_bcat(sb, &p->p_fd->fd_cmask, sizeof(p->p_fd->fd_cmask));
 	}
 	*sizep = size;
 }
 
 static void
 note_procstat_rlimit(void *arg, struct sbuf *sb, size_t *sizep)
 {
 	struct proc *p;
 	struct rlimit rlim[RLIM_NLIMITS];
 	size_t size;
 	int structsize, i;
 
 	p = (struct proc *)arg;
 	size = sizeof(structsize) + sizeof(rlim);
 	if (sb != NULL) {
 		KASSERT(*sizep == size, ("invalid size"));
 		structsize = sizeof(rlim);
 		sbuf_bcat(sb, &structsize, sizeof(structsize));
 		PROC_LOCK(p);
 		for (i = 0; i < RLIM_NLIMITS; i++)
 			lim_rlimit_proc(p, i, &rlim[i]);
 		PROC_UNLOCK(p);
 		sbuf_bcat(sb, rlim, sizeof(rlim));
 	}
 	*sizep = size;
 }
 
 static void
 note_procstat_osrel(void *arg, struct sbuf *sb, size_t *sizep)
 {
 	struct proc *p;
 	size_t size;
 	int structsize;
 
 	p = (struct proc *)arg;
 	size = sizeof(structsize) + sizeof(p->p_osrel);
 	if (sb != NULL) {
 		KASSERT(*sizep == size, ("invalid size"));
 		structsize = sizeof(p->p_osrel);
 		sbuf_bcat(sb, &structsize, sizeof(structsize));
 		sbuf_bcat(sb, &p->p_osrel, sizeof(p->p_osrel));
 	}
 	*sizep = size;
 }
 
 static void
 __elfN(note_procstat_psstrings)(void *arg, struct sbuf *sb, size_t *sizep)
 {
 	struct proc *p;
 	elf_ps_strings_t ps_strings;
 	size_t size;
 	int structsize;
 
 	p = (struct proc *)arg;
 	size = sizeof(structsize) + sizeof(ps_strings);
 	if (sb != NULL) {
 		KASSERT(*sizep == size, ("invalid size"));
 		structsize = sizeof(ps_strings);
 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32
 		ps_strings = PTROUT(p->p_sysent->sv_psstrings);
 #else
 		ps_strings = p->p_sysent->sv_psstrings;
 #endif
 		sbuf_bcat(sb, &structsize, sizeof(structsize));
 		sbuf_bcat(sb, &ps_strings, sizeof(ps_strings));
 	}
 	*sizep = size;
 }
 
 static void
 __elfN(note_procstat_auxv)(void *arg, struct sbuf *sb, size_t *sizep)
 {
 	struct proc *p;
 	size_t size;
 	int structsize;
 
 	p = (struct proc *)arg;
 	if (sb == NULL) {
 		size = 0;
 		sb = sbuf_new(NULL, NULL, 128, SBUF_FIXEDLEN);
 		sbuf_set_drain(sb, sbuf_drain_count, &size);
 		sbuf_bcat(sb, &structsize, sizeof(structsize));
 		PHOLD(p);
 		proc_getauxv(curthread, p, sb);
 		PRELE(p);
 		sbuf_finish(sb);
 		sbuf_delete(sb);
 		*sizep = size;
 	} else {
 		structsize = sizeof(Elf_Auxinfo);
 		sbuf_bcat(sb, &structsize, sizeof(structsize));
 		PHOLD(p);
 		proc_getauxv(curthread, p, sb);
 		PRELE(p);
 	}
 }
 
 static boolean_t
 __elfN(parse_notes)(struct image_params *imgp, Elf_Brandnote *checknote,
     int32_t *osrel, const Elf_Phdr *pnote)
 {
 	const Elf_Note *note, *note0, *note_end;
 	const char *note_name;
 	char *buf;
 	int i, error;
 	boolean_t res;
 
 	/* We need some limit, might as well use PAGE_SIZE. */
 	if (pnote == NULL || pnote->p_filesz > PAGE_SIZE)
 		return (FALSE);
 	ASSERT_VOP_LOCKED(imgp->vp, "parse_notes");
 	if (pnote->p_offset > PAGE_SIZE ||
 	    pnote->p_filesz > PAGE_SIZE - pnote->p_offset) {
 		VOP_UNLOCK(imgp->vp, 0);
 		buf = malloc(pnote->p_filesz, M_TEMP, M_WAITOK);
 		vn_lock(imgp->vp, LK_EXCLUSIVE | LK_RETRY);
 		error = vn_rdwr(UIO_READ, imgp->vp, buf, pnote->p_filesz,
 		    pnote->p_offset, UIO_SYSSPACE, IO_NODELOCKED,
 		    curthread->td_ucred, NOCRED, NULL, curthread);
 		if (error != 0) {
 			uprintf("i/o error PT_NOTE\n");
 			res = FALSE;
 			goto ret;
 		}
 		note = note0 = (const Elf_Note *)buf;
 		note_end = (const Elf_Note *)(buf + pnote->p_filesz);
 	} else {
 		note = note0 = (const Elf_Note *)(imgp->image_header +
 		    pnote->p_offset);
 		note_end = (const Elf_Note *)(imgp->image_header +
 		    pnote->p_offset + pnote->p_filesz);
 		buf = NULL;
 	}
 	for (i = 0; i < 100 && note >= note0 && note < note_end; i++) {
 		if (!aligned(note, Elf32_Addr) || (const char *)note_end -
 		    (const char *)note < sizeof(Elf_Note)) {
 			res = FALSE;
 			goto ret;
 		}
 		if (note->n_namesz != checknote->hdr.n_namesz ||
 		    note->n_descsz != checknote->hdr.n_descsz ||
 		    note->n_type != checknote->hdr.n_type)
 			goto nextnote;
 		note_name = (const char *)(note + 1);
 		if (note_name + checknote->hdr.n_namesz >=
 		    (const char *)note_end || strncmp(checknote->vendor,
 		    note_name, checknote->hdr.n_namesz) != 0)
 			goto nextnote;
 
 		/*
 		 * Fetch the osreldate for binary
 		 * from the ELF OSABI-note if necessary.
 		 */
 		if ((checknote->flags & BN_TRANSLATE_OSREL) != 0 &&
 		    checknote->trans_osrel != NULL) {
 			res = checknote->trans_osrel(note, osrel);
 			goto ret;
 		}
 		res = TRUE;
 		goto ret;
 nextnote:
 		note = (const Elf_Note *)((const char *)(note + 1) +
 		    roundup2(note->n_namesz, ELF_NOTE_ROUNDSIZE) +
 		    roundup2(note->n_descsz, ELF_NOTE_ROUNDSIZE));
 	}
 	res = FALSE;
 ret:
 	free(buf, M_TEMP);
 	return (res);
 }
 
 /*
  * Try to find the appropriate ABI-note section for checknote,
  * fetch the osreldate for binary from the ELF OSABI-note. Only the
  * first page of the image is searched, the same as for headers.
  */
 static boolean_t
 __elfN(check_note)(struct image_params *imgp, Elf_Brandnote *checknote,
     int32_t *osrel)
 {
 	const Elf_Phdr *phdr;
 	const Elf_Ehdr *hdr;
 	int i;
 
 	hdr = (const Elf_Ehdr *)imgp->image_header;
 	phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff);
 
 	for (i = 0; i < hdr->e_phnum; i++) {
 		if (phdr[i].p_type == PT_NOTE &&
 		    __elfN(parse_notes)(imgp, checknote, osrel, &phdr[i]))
 			return (TRUE);
 	}
 	return (FALSE);
 
 }
 
 /*
  * Tell kern_execve.c about it, with a little help from the linker.
  */
 static struct execsw __elfN(execsw) = {
 	__CONCAT(exec_, __elfN(imgact)),
 	__XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE))
 };
 EXEC_SET(__CONCAT(elf, __ELF_WORD_SIZE), __elfN(execsw));
 
 static vm_prot_t
 __elfN(trans_prot)(Elf_Word flags)
 {
 	vm_prot_t prot;
 
 	prot = 0;
 	if (flags & PF_X)
 		prot |= VM_PROT_EXECUTE;
 	if (flags & PF_W)
 		prot |= VM_PROT_WRITE;
 	if (flags & PF_R)
 		prot |= VM_PROT_READ;
 #if __ELF_WORD_SIZE == 32
 #if defined(__amd64__)
 	if (i386_read_exec && (flags & PF_R))
 		prot |= VM_PROT_EXECUTE;
 #endif
 #endif
 	return (prot);
 }
 
 static Elf_Word
 __elfN(untrans_prot)(vm_prot_t prot)
 {
 	Elf_Word flags;
 
 	flags = 0;
 	if (prot & VM_PROT_EXECUTE)
 		flags |= PF_X;
 	if (prot & VM_PROT_READ)
 		flags |= PF_R;
 	if (prot & VM_PROT_WRITE)
 		flags |= PF_W;
 	return (flags);
 }