2 * Copyright (c) 2000 David O'Brien
3 * Copyright (c) 1995-1996 Søren Schmidt
4 * Copyright (c) 1996 Peter Wemm
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
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
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.
30 * $FreeBSD: src/sys/kern/imgact_elf.c,v 1.73.2.13 2002/12/28 19:49:41 dillon Exp $
33 #include <sys/param.h>
35 #include <sys/fcntl.h>
37 #include <sys/imgact.h>
38 #include <sys/imgact_elf.h>
39 #include <sys/kernel.h>
40 #include <sys/malloc.h>
42 #include <sys/systm.h>
44 #include <sys/nlookup.h>
45 #include <sys/pioctl.h>
46 #include <sys/procfs.h>
47 #include <sys/resourcevar.h>
48 #include <sys/signalvar.h>
50 #include <sys/syscall.h>
51 #include <sys/sysctl.h>
52 #include <sys/sysent.h>
53 #include <sys/vnode.h>
54 #include <sys/eventhandler.h>
56 #include <cpu/lwbuf.h>
59 #include <vm/vm_kern.h>
60 #include <vm/vm_param.h>
63 #include <vm/vm_map.h>
64 #include <vm/vm_object.h>
65 #include <vm/vm_extern.h>
67 #include <machine/elf.h>
68 #include <machine/md_var.h>
69 #include <sys/mount.h>
72 #define OLD_EI_BRAND 8
73 #define truncps(va,ps) ((va) & ~(ps - 1))
74 #define aligned(a,t) (truncps((u_long)(a), sizeof(t)) == (u_long)(a))
76 static int __elfN(check_header)(const Elf_Ehdr *hdr);
77 static Elf_Brandinfo *__elfN(get_brandinfo)(struct image_params *imgp,
78 const char *interp, int32_t *osrel);
79 static int __elfN(load_file)(struct proc *p, const char *file, u_long *addr,
81 static int __elfN(load_section)(struct proc *p,
82 struct vmspace *vmspace, struct vnode *vp,
83 vm_offset_t offset, caddr_t vmaddr, size_t memsz, size_t filsz,
85 static int __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp);
86 static boolean_t __elfN(bsd_trans_osrel)(const Elf_Note *note,
88 static boolean_t __elfN(check_note)(struct image_params *imgp,
89 Elf_Brandnote *checknote, int32_t *osrel);
90 static vm_prot_t __elfN(trans_prot)(Elf_Word);
91 static Elf_Word __elfN(untrans_prot)(vm_prot_t);
92 static boolean_t check_PT_NOTE(struct image_params *imgp,
93 Elf_Brandnote *checknote, int32_t *osrel, const Elf_Phdr * pnote);
94 static boolean_t extract_interpreter(struct image_params *imgp,
95 const Elf_Phdr *pinterpreter, char *data);
96 static u_long pie_base_hint(struct proc *p);
98 static int elf_legacy_coredump = 0;
99 static int __elfN(fallback_brand) = -1;
100 static int elf_pie_base_mmap = 0;
101 #if defined(__x86_64__)
102 SYSCTL_NODE(_kern, OID_AUTO, elf64, CTLFLAG_RW, 0, "");
103 SYSCTL_INT(_debug, OID_AUTO, elf64_legacy_coredump, CTLFLAG_RW,
104 &elf_legacy_coredump, 0, "legacy coredump mode");
105 SYSCTL_INT(_kern_elf64, OID_AUTO, fallback_brand, CTLFLAG_RW,
106 &elf64_fallback_brand, 0, "ELF64 brand of last resort");
107 TUNABLE_INT("kern.elf64.fallback_brand", &elf64_fallback_brand);
108 SYSCTL_INT(_kern_elf64, OID_AUTO, pie_base_mmap, CTLFLAG_RW,
109 &elf_pie_base_mmap, 0,
110 "choose a base address for PIE as if it is mapped with mmap()");
111 TUNABLE_INT("kern.elf64.pie_base_mmap", &elf_pie_base_mmap);
112 #else /* i386 assumed */
113 SYSCTL_NODE(_kern, OID_AUTO, elf32, CTLFLAG_RW, 0, "");
114 SYSCTL_INT(_debug, OID_AUTO, elf32_legacy_coredump, CTLFLAG_RW,
115 &elf_legacy_coredump, 0, "legacy coredump mode");
116 SYSCTL_INT(_kern_elf32, OID_AUTO, fallback_brand, CTLFLAG_RW,
117 &elf32_fallback_brand, 0, "ELF32 brand of last resort");
118 TUNABLE_INT("kern.elf32.fallback_brand", &elf32_fallback_brand);
119 SYSCTL_INT(_kern_elf32, OID_AUTO, pie_base_mmap, CTLFLAG_RW,
120 &elf_pie_base_mmap, 0,
121 "choose a base address for PIE as if it is mapped with mmap()");
122 TUNABLE_INT("kern.elf32.pie_base_mmap", &elf_pie_base_mmap);
125 static Elf_Brandinfo *elf_brand_list[MAX_BRANDS];
127 static const char DRAGONFLY_ABI_VENDOR[] = "DragonFly";
129 Elf_Brandnote __elfN(dragonfly_brandnote) = {
130 .hdr.n_namesz = sizeof(DRAGONFLY_ABI_VENDOR),
131 .hdr.n_descsz = sizeof(int32_t),
133 .vendor = DRAGONFLY_ABI_VENDOR,
134 .flags = BN_TRANSLATE_OSREL,
135 .trans_osrel = __elfN(bsd_trans_osrel),
139 __elfN(insert_brand_entry)(Elf_Brandinfo *entry)
143 for (i = 0; i < MAX_BRANDS; i++) {
144 if (elf_brand_list[i] == NULL) {
145 elf_brand_list[i] = entry;
149 if (i == MAX_BRANDS) {
150 uprintf("WARNING: %s: could not insert brandinfo entry: %p\n",
158 __elfN(remove_brand_entry)(Elf_Brandinfo *entry)
162 for (i = 0; i < MAX_BRANDS; i++) {
163 if (elf_brand_list[i] == entry) {
164 elf_brand_list[i] = NULL;
174 * Check if an elf brand is being used anywhere in the system.
176 * Used by the linux emulation module unloader. This isn't safe from
179 struct elf_brand_inuse_info {
181 Elf_Brandinfo *entry;
184 static int elf_brand_inuse_callback(struct proc *p, void *data);
187 __elfN(brand_inuse)(Elf_Brandinfo *entry)
189 struct elf_brand_inuse_info info;
193 allproc_scan(elf_brand_inuse_callback, &info, 0);
199 elf_brand_inuse_callback(struct proc *p, void *data)
201 struct elf_brand_inuse_info *info = data;
203 if (p->p_sysent == info->entry->sysvec) {
211 __elfN(check_header)(const Elf_Ehdr *hdr)
217 hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS ||
218 hdr->e_ident[EI_DATA] != ELF_TARG_DATA ||
219 hdr->e_ident[EI_VERSION] != EV_CURRENT ||
220 hdr->e_phentsize != sizeof(Elf_Phdr) ||
221 hdr->e_ehsize != sizeof(Elf_Ehdr) ||
222 hdr->e_version != ELF_TARG_VER)
226 * Make sure we have at least one brand for this machine.
229 for (i = 0; i < MAX_BRANDS; i++) {
230 bi = elf_brand_list[i];
231 if (bi != NULL && bi->machine == hdr->e_machine)
241 __elfN(load_section)(struct proc *p, struct vmspace *vmspace, struct vnode *vp,
242 vm_offset_t offset, caddr_t vmaddr, size_t memsz,
243 size_t filsz, vm_prot_t prot)
246 vm_offset_t map_addr;
252 vm_offset_t file_addr;
254 object = vp->v_object;
258 * In most cases we will be able to use a shared lock on the
259 * object we are inserting into the map. The lock will be
260 * upgraded in situations where new VM pages must be allocated.
262 vm_object_hold_shared(object);
266 * It's necessary to fail if the filsz + offset taken from the
267 * header is greater than the actual file pager object's size.
268 * If we were to allow this, then the vm_map_find() below would
269 * walk right off the end of the file object and into the ether.
271 * While I'm here, might as well check for something else that
272 * is invalid: filsz cannot be greater than memsz.
274 if ((off_t)filsz + offset > vp->v_filesize || filsz > memsz) {
275 uprintf("elf_load_section: truncated ELF file\n");
276 vm_object_drop(object);
280 map_addr = trunc_page((vm_offset_t)vmaddr);
281 file_addr = trunc_page(offset);
284 * We have two choices. We can either clear the data in the last page
285 * of an oversized mapping, or we can start the anon mapping a page
286 * early and copy the initialized data into that first page. We
287 * choose the second..
290 map_len = trunc_page(offset+filsz) - file_addr;
292 map_len = round_page(offset+filsz) - file_addr;
295 vm_object_reference_locked(object);
297 /* cow flags: don't dump readonly sections in core */
298 cow = MAP_COPY_ON_WRITE | MAP_PREFAULT;
299 if ((prot & VM_PROT_WRITE) == 0)
300 cow |= MAP_DISABLE_COREDUMP;
302 cow |= MAP_PREFAULT_RELOCK;
304 count = vm_map_entry_reserve(MAP_RESERVE_COUNT);
305 vm_map_lock(&vmspace->vm_map);
306 rv = vm_map_insert(&vmspace->vm_map, &count,
308 file_addr, /* file offset */
309 map_addr, /* virtual start */
310 map_addr + map_len,/* virtual end */
313 prot, VM_PROT_ALL, cow);
314 vm_map_unlock(&vmspace->vm_map);
315 vm_map_entry_release(count);
318 * NOTE: Object must have a hold ref when calling
319 * vm_object_deallocate().
321 if (rv != KERN_SUCCESS) {
322 vm_object_drop(object);
323 vm_object_deallocate(object);
327 /* we can stop now if we've covered it all */
328 if (memsz == filsz) {
329 vm_object_drop(object);
335 * We have to get the remaining bit of the file into the first part
336 * of the oversized map segment. This is normally because the .data
337 * segment in the file is extended to provide bss. It's a neat idea
338 * to try and save a page, but it's a pain in the behind to implement.
340 copy_len = (offset + filsz) - trunc_page(offset + filsz);
341 map_addr = trunc_page((vm_offset_t)vmaddr + filsz);
342 map_len = round_page((vm_offset_t)vmaddr + memsz) - map_addr;
344 /* This had damn well better be true! */
346 count = vm_map_entry_reserve(MAP_RESERVE_COUNT);
347 vm_map_lock(&vmspace->vm_map);
348 rv = vm_map_insert(&vmspace->vm_map, &count,
355 VM_PROT_ALL, VM_PROT_ALL, 0);
356 vm_map_unlock(&vmspace->vm_map);
357 vm_map_entry_release(count);
358 if (rv != KERN_SUCCESS) {
359 vm_object_drop(object);
366 struct lwbuf lwb_cache;
369 m = vm_fault_object_page(object, trunc_page(offset + filsz),
370 VM_PROT_READ, 0, &shared, &error);
371 vm_object_drop(object);
373 lwb = lwbuf_alloc(m, &lwb_cache);
374 error = copyout((caddr_t)lwbuf_kva(lwb),
375 (caddr_t)map_addr, copy_len);
380 vm_object_drop(object);
384 * set it to the specified protection
387 vm_map_protect(&vmspace->vm_map,
388 map_addr, map_addr + map_len,
395 * Load the file "file" into memory. It may be either a shared object
398 * The "addr" reference parameter is in/out. On entry, it specifies
399 * the address where a shared object should be loaded. If the file is
400 * an executable, this value is ignored. On exit, "addr" specifies
401 * where the file was actually loaded.
403 * The "entry" reference parameter is out only. On exit, it specifies
404 * the entry point for the loaded file.
407 __elfN(load_file)(struct proc *p, const char *file, u_long *addr, u_long *entry)
410 struct nlookupdata nd;
412 struct image_params image_params;
414 const Elf_Ehdr *hdr = NULL;
415 const Elf_Phdr *phdr = NULL;
416 struct nlookupdata *nd;
417 struct vmspace *vmspace = p->p_vmspace;
419 struct image_params *imgp;
420 struct mount *topmnt;
423 u_long base_addr = 0;
424 int error, i, numsegs;
426 tempdata = kmalloc(sizeof(*tempdata), M_TEMP, M_WAITOK);
428 attr = &tempdata->attr;
429 imgp = &tempdata->image_params;
432 * Initialize part of the common data
436 imgp->firstpage = NULL;
437 imgp->image_header = NULL;
440 error = nlookup_init(nd, file, UIO_SYSSPACE, NLC_FOLLOW);
444 error = cache_vget(&nd->nl_nch, nd->nl_cred,
445 LK_SHARED, &imgp->vp);
446 topmnt = nd->nl_nch.mount;
452 * Check permissions, modes, uid, etc on the file, and "open" it.
454 error = exec_check_permissions(imgp, topmnt);
460 error = exec_map_first_page(imgp);
462 * Also make certain that the interpreter stays the same, so set
463 * its VTEXT flag, too.
466 vsetflags(imgp->vp, VTEXT);
471 hdr = (const Elf_Ehdr *)imgp->image_header;
472 if ((error = __elfN(check_header)(hdr)) != 0)
474 if (hdr->e_type == ET_DYN)
476 else if (hdr->e_type == ET_EXEC)
483 /* Only support headers that fit within first page for now */
484 /* (multiplication of two Elf_Half fields will not overflow) */
485 if ((hdr->e_phoff > PAGE_SIZE) ||
486 (hdr->e_phentsize * hdr->e_phnum) > PAGE_SIZE - hdr->e_phoff) {
491 phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff);
492 if (!aligned(phdr, Elf_Addr)) {
497 for (i = 0, numsegs = 0; i < hdr->e_phnum; i++) {
498 if (phdr[i].p_type == PT_LOAD && phdr[i].p_memsz != 0) {
499 /* Loadable segment */
500 prot = __elfN(trans_prot)(phdr[i].p_flags);
501 error = __elfN(load_section)(
502 p, vmspace, imgp->vp,
504 (caddr_t)phdr[i].p_vaddr +
507 phdr[i].p_filesz, prot);
511 * Establish the base address if this is the
515 base_addr = trunc_page(phdr[i].p_vaddr + rbase);
520 *entry = (unsigned long)hdr->e_entry + rbase;
524 exec_unmap_first_page(imgp);
529 kfree(tempdata, M_TEMP);
534 static Elf_Brandinfo *
535 __elfN(get_brandinfo)(struct image_params *imgp, const char *interp,
538 const Elf_Ehdr *hdr = (const Elf_Ehdr *)imgp->image_header;
543 /* We support four types of branding -- (1) the ELF EI_OSABI field
544 * that SCO added to the ELF spec, (2) FreeBSD 3.x's traditional string
545 * branding within the ELF header, (3) path of the `interp_path' field,
546 * and (4) the ".note.ABI-tag" ELF section.
549 /* Look for an ".note.ABI-tag" ELF section */
550 for (i = 0; i < MAX_BRANDS; i++) {
551 bi = elf_brand_list[i];
555 if (hdr->e_machine == bi->machine && (bi->flags &
556 (BI_BRAND_NOTE|BI_BRAND_NOTE_MANDATORY)) != 0) {
557 ret = __elfN(check_note)(imgp, bi->brand_note, osrel);
563 /* If the executable has a brand, search for it in the brand list. */
564 for (i = 0; i < MAX_BRANDS; i++) {
565 bi = elf_brand_list[i];
567 if (bi == NULL || bi->flags & BI_BRAND_NOTE_MANDATORY)
569 if (hdr->e_machine == bi->machine &&
570 (hdr->e_ident[EI_OSABI] == bi->brand ||
571 strncmp((const char *)&hdr->e_ident[OLD_EI_BRAND],
572 bi->compat_3_brand, strlen(bi->compat_3_brand)) == 0))
576 /* Lacking a known brand, search for a recognized interpreter. */
577 if (interp != NULL) {
578 for (i = 0; i < MAX_BRANDS; i++) {
579 bi = elf_brand_list[i];
581 if (bi == NULL || bi->flags & BI_BRAND_NOTE_MANDATORY)
583 if (hdr->e_machine == bi->machine &&
584 strcmp(interp, bi->interp_path) == 0)
589 /* Lacking a recognized interpreter, try the default brand */
590 for (i = 0; i < MAX_BRANDS; i++) {
591 bi = elf_brand_list[i];
593 if (bi == NULL || bi->flags & BI_BRAND_NOTE_MANDATORY)
595 if (hdr->e_machine == bi->machine &&
596 __elfN(fallback_brand) == bi->brand)
603 __CONCAT(exec_,__elfN(imgact))(struct image_params *imgp)
605 const Elf_Ehdr *hdr = (const Elf_Ehdr *) imgp->image_header;
606 const Elf_Phdr *phdr;
607 Elf_Auxargs *elf_auxargs;
608 struct vmspace *vmspace;
610 u_long text_size = 0, data_size = 0, total_size = 0;
611 u_long text_addr = 0, data_addr = 0;
612 u_long seg_size, seg_addr;
613 u_long addr, baddr, et_dyn_addr = 0, entry = 0, proghdr = 0;
618 const char *newinterp = NULL;
619 Elf_Brandinfo *brand_info;
623 * Do we have a valid ELF header ?
625 * Only allow ET_EXEC & ET_DYN here, reject ET_DYN later if a particular
626 * brand doesn't support it. Both DragonFly platforms do by default.
628 if (__elfN(check_header)(hdr) != 0 ||
629 (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN))
633 * From here on down, we return an errno, not -1, as we've
634 * detected an ELF file.
637 if ((hdr->e_phoff > PAGE_SIZE) ||
638 (hdr->e_phoff + hdr->e_phentsize * hdr->e_phnum) > PAGE_SIZE) {
639 /* Only support headers in first page for now */
642 phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff);
643 if (!aligned(phdr, Elf_Addr))
647 for (i = 0; i < hdr->e_phnum; i++) {
648 if (phdr[i].p_type == PT_LOAD) {
650 baddr = phdr[i].p_vaddr;
654 if (phdr[i].p_type == PT_INTERP) {
656 * If interp is already defined there are more than
657 * one PT_INTERP program headers present. Take only
658 * the first one and ignore the rest.
663 if (phdr[i].p_filesz == 0 ||
664 phdr[i].p_filesz > PAGE_SIZE ||
665 phdr[i].p_filesz > MAXPATHLEN)
668 interp = kmalloc(phdr[i].p_filesz, M_TEMP, M_WAITOK);
669 failure = extract_interpreter(imgp, &phdr[i], interp);
671 kfree(interp, M_TEMP);
678 brand_info = __elfN(get_brandinfo)(imgp, interp, &osrel);
679 if (brand_info == NULL) {
680 uprintf("ELF binary type \"%u\" not known.\n",
681 hdr->e_ident[EI_OSABI]);
683 kfree(interp, M_TEMP);
686 if (hdr->e_type == ET_DYN) {
687 if ((brand_info->flags & BI_CAN_EXEC_DYN) == 0) {
689 kfree(interp, M_TEMP);
693 * If p_vaddr field of PT_LOAD program header is zero and type of an
694 * executale is ET_DYN, then it must be a position independent
695 * executable (PIE). In this case the system needs to pick a base
696 * address for us. Set et_dyn_addr to non-zero and choose the actual
697 * address when we are ready.
703 if (interp != NULL && brand_info->interp_newpath != NULL)
704 newinterp = brand_info->interp_newpath;
706 exec_new_vmspace(imgp, NULL);
709 * Yeah, I'm paranoid. There is every reason in the world to get
710 * VTEXT now since from here on out, there are places we can have
711 * a context switch. Better safe than sorry; I really don't want
712 * the file to change while it's being loaded.
714 vsetflags(imgp->vp, VTEXT);
716 vmspace = imgp->proc->p_vmspace;
717 /* Choose the base address for dynamic executables if we need to. */
719 et_dyn_addr = pie_base_hint(imgp->proc);
721 for (i = 0; i < hdr->e_phnum; i++) {
722 switch (phdr[i].p_type) {
723 case PT_LOAD: /* Loadable segment */
724 if (phdr[i].p_memsz == 0)
726 prot = __elfN(trans_prot)(phdr[i].p_flags);
728 if ((error = __elfN(load_section)(
733 (caddr_t)phdr[i].p_vaddr + et_dyn_addr,
738 kfree (interp, M_TEMP);
743 * If this segment contains the program headers,
744 * remember their virtual address for the AT_PHDR
745 * aux entry. Static binaries don't usually include
748 if (phdr[i].p_offset == 0 &&
749 hdr->e_phoff + hdr->e_phnum * hdr->e_phentsize
751 proghdr = phdr[i].p_vaddr + hdr->e_phoff +
754 seg_addr = trunc_page(phdr[i].p_vaddr + et_dyn_addr);
755 seg_size = round_page(phdr[i].p_memsz +
756 phdr[i].p_vaddr + et_dyn_addr - seg_addr);
759 * Is this .text or .data? We can't use
760 * VM_PROT_WRITE or VM_PROT_EXEC, it breaks the
761 * alpha terribly and possibly does other bad
762 * things so we stick to the old way of figuring
763 * it out: If the segment contains the program
764 * entry point, it's a text segment, otherwise it
767 * Note that obreak() assumes that data_addr +
768 * data_size == end of data load area, and the ELF
769 * file format expects segments to be sorted by
770 * address. If multiple data segments exist, the
771 * last one will be used.
773 if (hdr->e_entry >= phdr[i].p_vaddr &&
774 hdr->e_entry < (phdr[i].p_vaddr +
776 text_size = seg_size;
777 text_addr = seg_addr;
778 entry = (u_long)hdr->e_entry + et_dyn_addr;
780 data_size = seg_size;
781 data_addr = seg_addr;
783 total_size += seg_size;
786 * Check limits. It should be safe to check the
787 * limits after loading the segment since we do
788 * not actually fault in all the segment's pages.
791 imgp->proc->p_rlimit[RLIMIT_DATA].rlim_cur ||
792 text_size > maxtsiz ||
794 imgp->proc->p_rlimit[RLIMIT_VMEM].rlim_cur) {
796 kfree(interp, M_TEMP);
801 case PT_PHDR: /* Program header table info */
802 proghdr = phdr[i].p_vaddr + et_dyn_addr;
809 vmspace->vm_tsize = text_size; /* in bytes */
810 vmspace->vm_taddr = (caddr_t)(uintptr_t)text_addr;
811 vmspace->vm_dsize = data_size; /* in bytes */
812 vmspace->vm_daddr = (caddr_t)(uintptr_t)data_addr;
814 addr = ELF_RTLD_ADDR(vmspace);
816 imgp->entry_addr = entry;
818 imgp->proc->p_sysent = brand_info->sysvec;
820 if (interp != NULL) {
821 int have_interp = FALSE;
822 if (brand_info->emul_path != NULL &&
823 brand_info->emul_path[0] != '\0') {
824 path = kmalloc(MAXPATHLEN, M_TEMP, M_WAITOK);
825 ksnprintf(path, MAXPATHLEN, "%s%s",
826 brand_info->emul_path, interp);
827 error = __elfN(load_file)(imgp->proc, path, &addr,
833 if (!have_interp && newinterp != NULL) {
834 error = __elfN(load_file)(imgp->proc, newinterp,
835 &addr, &imgp->entry_addr);
840 error = __elfN(load_file)(imgp->proc, interp, &addr,
844 uprintf("ELF interpreter %s not found\n", interp);
845 kfree(interp, M_TEMP);
848 kfree(interp, M_TEMP);
853 * Construct auxargs table (used by the fixup routine)
855 elf_auxargs = kmalloc(sizeof(Elf_Auxargs), M_TEMP, M_WAITOK);
856 elf_auxargs->execfd = -1;
857 elf_auxargs->phdr = proghdr;
858 elf_auxargs->phent = hdr->e_phentsize;
859 elf_auxargs->phnum = hdr->e_phnum;
860 elf_auxargs->pagesz = PAGE_SIZE;
861 elf_auxargs->base = addr;
862 elf_auxargs->flags = 0;
863 elf_auxargs->entry = entry;
865 imgp->auxargs = elf_auxargs;
866 imgp->interpreted = 0;
867 imgp->proc->p_osrel = osrel;
873 __elfN(dragonfly_fixup)(register_t **stack_base, struct image_params *imgp)
875 Elf_Auxargs *args = (Elf_Auxargs *)imgp->auxargs;
879 base = (Elf_Addr *)*stack_base;
880 pos = base + (imgp->args->argc + imgp->args->envc + 2);
882 if (args->execfd != -1)
883 AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd);
884 AUXARGS_ENTRY(pos, AT_PHDR, args->phdr);
885 AUXARGS_ENTRY(pos, AT_PHENT, args->phent);
886 AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum);
887 AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz);
888 AUXARGS_ENTRY(pos, AT_FLAGS, args->flags);
889 AUXARGS_ENTRY(pos, AT_ENTRY, args->entry);
890 AUXARGS_ENTRY(pos, AT_BASE, args->base);
891 if (imgp->execpathp != 0)
892 AUXARGS_ENTRY(pos, AT_EXECPATH, imgp->execpathp);
893 AUXARGS_ENTRY(pos, AT_OSRELDATE, osreldate);
894 AUXARGS_ENTRY(pos, AT_NULL, 0);
896 kfree(imgp->auxargs, M_TEMP);
897 imgp->auxargs = NULL;
900 suword64(base, (long)imgp->args->argc);
901 *stack_base = (register_t *)base;
906 * Code for generating ELF core dumps.
909 typedef int (*segment_callback)(vm_map_entry_t, void *);
911 /* Closure for cb_put_phdr(). */
912 struct phdr_closure {
913 Elf_Phdr *phdr; /* Program header to fill in (incremented) */
914 Elf_Phdr *phdr_max; /* Pointer bound for error check */
915 Elf_Off offset; /* Offset of segment in core file */
918 /* Closure for cb_size_segment(). */
919 struct sseg_closure {
920 int count; /* Count of writable segments. */
921 size_t vsize; /* Total size of all writable segments. */
924 /* Closure for cb_put_fp(). */
927 struct vn_hdr *vnh_max;
932 typedef struct elf_buf {
938 static void *target_reserve(elf_buf_t target, size_t bytes, int *error);
940 static int cb_put_phdr (vm_map_entry_t, void *);
941 static int cb_size_segment (vm_map_entry_t, void *);
942 static int cb_fpcount_segment(vm_map_entry_t, void *);
943 static int cb_put_fp(vm_map_entry_t, void *);
946 static int each_segment (struct proc *, segment_callback, void *, int);
947 static int __elfN(corehdr)(struct lwp *, int, struct file *, struct ucred *,
949 enum putmode { WRITE, DRYRUN };
950 static int __elfN(puthdr)(struct lwp *, elf_buf_t, int sig, enum putmode,
952 static int elf_putallnotes(struct lwp *, elf_buf_t, int, enum putmode);
953 static int __elfN(putnote)(elf_buf_t, const char *, int, const void *, size_t);
955 static int elf_putsigs(struct lwp *, elf_buf_t);
956 static int elf_puttextvp(struct proc *, elf_buf_t);
957 static int elf_putfiles(struct proc *, elf_buf_t, struct file *);
960 __elfN(coredump)(struct lwp *lp, int sig, struct vnode *vp, off_t limit)
965 if ((error = falloc(NULL, &fp, NULL)) != 0)
967 fsetcred(fp, lp->lwp_proc->p_ucred);
972 fp->f_type = DTYPE_VNODE;
973 fp->f_flag = O_CREAT|O_WRONLY|O_NOFOLLOW;
974 fp->f_ops = &vnode_fileops;
977 error = generic_elf_coredump(lp, sig, fp, limit);
981 fp->f_ops = &badfileops;
988 generic_elf_coredump(struct lwp *lp, int sig, struct file *fp, off_t limit)
990 struct proc *p = lp->lwp_proc;
991 struct ucred *cred = p->p_ucred;
993 struct sseg_closure seginfo;
994 struct elf_buf target;
997 kprintf("can't dump core - null fp\n");
1000 * Size the program segments
1004 each_segment(p, cb_size_segment, &seginfo, 1);
1007 * Calculate the size of the core file header area by making
1008 * a dry run of generating it. Nothing is written, but the
1009 * size is calculated.
1011 bzero(&target, sizeof(target));
1012 __elfN(puthdr)(lp, &target, sig, DRYRUN, seginfo.count, fp);
1014 if (target.off + seginfo.vsize >= limit)
1018 * Allocate memory for building the header, fill it up,
1021 target.off_max = target.off;
1023 target.buf = kmalloc(target.off_max, M_TEMP, M_WAITOK|M_ZERO);
1025 error = __elfN(corehdr)(lp, sig, fp, cred, seginfo.count, &target);
1027 /* Write the contents of all of the writable segments. */
1033 php = (Elf_Phdr *)(target.buf + sizeof(Elf_Ehdr)) + 1;
1034 for (i = 0; i < seginfo.count; i++) {
1035 error = fp_write(fp, (caddr_t)php->p_vaddr,
1036 php->p_filesz, &nbytes, UIO_USERSPACE);
1042 kfree(target.buf, M_TEMP);
1048 * A callback for each_segment() to write out the segment's
1049 * program header entry.
1052 cb_put_phdr(vm_map_entry_t entry, void *closure)
1054 struct phdr_closure *phc = closure;
1055 Elf_Phdr *phdr = phc->phdr;
1057 if (phc->phdr == phc->phdr_max)
1060 phc->offset = round_page(phc->offset);
1062 phdr->p_type = PT_LOAD;
1063 phdr->p_offset = phc->offset;
1064 phdr->p_vaddr = entry->start;
1066 phdr->p_filesz = phdr->p_memsz = entry->end - entry->start;
1067 phdr->p_align = PAGE_SIZE;
1068 phdr->p_flags = __elfN(untrans_prot)(entry->protection);
1070 phc->offset += phdr->p_filesz;
1076 * A callback for each_writable_segment() to gather information about
1077 * the number of segments and their total size.
1080 cb_size_segment(vm_map_entry_t entry, void *closure)
1082 struct sseg_closure *ssc = closure;
1085 ssc->vsize += entry->end - entry->start;
1090 * A callback for each_segment() to gather information about
1091 * the number of text segments.
1094 cb_fpcount_segment(vm_map_entry_t entry, void *closure)
1096 int *count = closure;
1099 if (entry->object.vm_object->type == OBJT_VNODE) {
1100 vp = (struct vnode *)entry->object.vm_object->handle;
1101 if ((vp->v_flag & VCKPT) && curproc->p_textvp == vp)
1109 cb_put_fp(vm_map_entry_t entry, void *closure)
1111 struct fp_closure *fpc = closure;
1112 struct vn_hdr *vnh = fpc->vnh;
1113 Elf_Phdr *phdr = &vnh->vnh_phdr;
1118 * If an entry represents a vnode then write out a file handle.
1120 * If we are checkpointing a checkpoint-restored program we do
1121 * NOT record the filehandle for the old checkpoint vnode (which
1122 * is mapped all over the place). Instead we rely on the fact
1123 * that a checkpoint-restored program does not mmap() the checkpt
1124 * vnode NOCORE, so its contents will be written out to the
1125 * new checkpoint file. This is necessary because the 'old'
1126 * checkpoint file is typically destroyed when a new one is created
1127 * and thus cannot be used to restore the new checkpoint.
1129 * Theoretically we could create a chain of checkpoint files and
1130 * operate the checkpointing operation kinda like an incremental
1131 * checkpoint, but a checkpoint restore would then likely wind up
1132 * referencing many prior checkpoint files and that is a bit over
1133 * the top for the purpose of the checkpoint API.
1135 if (entry->object.vm_object->type == OBJT_VNODE) {
1136 vp = (struct vnode *)entry->object.vm_object->handle;
1137 if ((vp->v_flag & VCKPT) && curproc->p_textvp == vp)
1139 if (vnh == fpc->vnh_max)
1143 vnh->vnh_fh.fh_fsid = vp->v_mount->mnt_stat.f_fsid;
1144 error = VFS_VPTOFH(vp, &vnh->vnh_fh.fh_fid);
1146 char *freepath, *fullpath;
1149 * This is actually a relatively common occurance,
1150 * so don't spew on the console by default.
1152 if (vn_fullpath(curproc, vp, &fullpath, &freepath, 0)) {
1154 kprintf("Warning: coredump, error %d: cannot store file handle for vnode %p\n", error, vp);
1157 kprintf("Warning: coredump, error %d: cannot store file handle for %s\n", error, fullpath);
1158 kfree(freepath, M_TEMP);
1163 phdr->p_type = PT_LOAD;
1164 phdr->p_offset = 0; /* not written to core */
1165 phdr->p_vaddr = entry->start;
1167 phdr->p_filesz = phdr->p_memsz = entry->end - entry->start;
1168 phdr->p_align = PAGE_SIZE;
1170 if (entry->protection & VM_PROT_READ)
1171 phdr->p_flags |= PF_R;
1172 if (entry->protection & VM_PROT_WRITE)
1173 phdr->p_flags |= PF_W;
1174 if (entry->protection & VM_PROT_EXECUTE)
1175 phdr->p_flags |= PF_X;
1183 * For each writable segment in the process's memory map, call the given
1184 * function with a pointer to the map entry and some arbitrary
1185 * caller-supplied data.
1188 each_segment(struct proc *p, segment_callback func, void *closure, int writable)
1191 vm_map_t map = &p->p_vmspace->vm_map;
1192 vm_map_entry_t entry;
1194 RB_FOREACH(entry, vm_map_rb_tree, &map->rb_root) {
1200 * Don't dump inaccessible mappings, deal with legacy
1203 * Note that read-only segments related to the elf binary
1204 * are marked MAP_ENTRY_NOCOREDUMP now so we no longer
1205 * need to arbitrarily ignore such segments.
1207 if (elf_legacy_coredump) {
1208 if (writable && (entry->protection & VM_PROT_RW) != VM_PROT_RW)
1211 if (writable && (entry->protection & VM_PROT_ALL) == 0)
1216 * Dont include memory segment in the coredump if
1217 * MAP_NOCORE is set in mmap(2) or MADV_NOCORE in
1220 * Currently we only dump normal VM object maps. We do
1221 * not dump submaps or virtual page tables.
1223 if (writable && (entry->eflags & MAP_ENTRY_NOCOREDUMP))
1225 if (entry->maptype != VM_MAPTYPE_NORMAL)
1227 if ((obj = entry->object.vm_object) == NULL)
1231 * Find the bottom-most object, leaving the base object
1232 * and the bottom-most object held (but only one hold
1233 * if they happen to be the same).
1235 vm_object_hold_shared(obj);
1238 while (lobj && (tobj = lobj->backing_object) != NULL) {
1239 KKASSERT(tobj != obj);
1240 vm_object_hold_shared(tobj);
1241 if (tobj == lobj->backing_object) {
1243 vm_object_lock_swap();
1244 vm_object_drop(lobj);
1248 vm_object_drop(tobj);
1253 * The callback only applies to default, swap, or vnode
1254 * objects. Other types of objects such as memory-mapped
1255 * devices are ignored.
1257 if (lobj->type == OBJT_DEFAULT || lobj->type == OBJT_SWAP ||
1258 lobj->type == OBJT_VNODE) {
1259 error = (*func)(entry, closure);
1262 vm_object_drop(lobj);
1263 vm_object_drop(obj);
1270 target_reserve(elf_buf_t target, size_t bytes, int *error)
1275 if (target->off + bytes > target->off_max)
1278 res = target->buf + target->off;
1280 target->off += bytes;
1285 * Write the core file header to the file, including padding up to
1286 * the page boundary.
1289 __elfN(corehdr)(struct lwp *lp, int sig, struct file *fp, struct ucred *cred,
1290 int numsegs, elf_buf_t target)
1296 * Fill in the header. The fp is passed so we can detect and flag
1297 * a checkpoint file pointer within the core file itself, because
1298 * it may not be restored from the same file handle.
1300 error = __elfN(puthdr)(lp, target, sig, WRITE, numsegs, fp);
1302 /* Write it to the core file. */
1304 error = fp_write(fp, target->buf, target->off, &nbytes,
1311 __elfN(puthdr)(struct lwp *lp, elf_buf_t target, int sig, enum putmode mode,
1312 int numsegs, struct file *fp)
1314 struct proc *p = lp->lwp_proc;
1322 ehdr = target_reserve(target, sizeof(Elf_Ehdr), &error);
1324 phoff = target->off;
1325 phdr = target_reserve(target, (numsegs + 1) * sizeof(Elf_Phdr), &error);
1327 noteoff = target->off;
1329 elf_putallnotes(lp, target, sig, mode);
1330 notesz = target->off - noteoff;
1333 * put extra cruft for dumping process state here
1334 * - we really want it be before all the program
1336 * - we just need to update the offset accordingly
1337 * and GDB will be none the wiser.
1340 error = elf_puttextvp(p, target);
1342 error = elf_putsigs(lp, target);
1344 error = elf_putfiles(p, target, fp);
1347 * Align up to a page boundary for the program segments. The
1348 * actual data will be written to the outptu file, not to elf_buf_t,
1349 * so we do not have to do any further bounds checking.
1351 target->off = round_page(target->off);
1352 if (error == 0 && ehdr != NULL) {
1354 * Fill in the ELF header.
1356 ehdr->e_ident[EI_MAG0] = ELFMAG0;
1357 ehdr->e_ident[EI_MAG1] = ELFMAG1;
1358 ehdr->e_ident[EI_MAG2] = ELFMAG2;
1359 ehdr->e_ident[EI_MAG3] = ELFMAG3;
1360 ehdr->e_ident[EI_CLASS] = ELF_CLASS;
1361 ehdr->e_ident[EI_DATA] = ELF_DATA;
1362 ehdr->e_ident[EI_VERSION] = EV_CURRENT;
1363 ehdr->e_ident[EI_OSABI] = ELFOSABI_NONE;
1364 ehdr->e_ident[EI_ABIVERSION] = 0;
1365 ehdr->e_ident[EI_PAD] = 0;
1366 ehdr->e_type = ET_CORE;
1367 ehdr->e_machine = ELF_ARCH;
1368 ehdr->e_version = EV_CURRENT;
1370 ehdr->e_phoff = phoff;
1372 ehdr->e_ehsize = sizeof(Elf_Ehdr);
1373 ehdr->e_phentsize = sizeof(Elf_Phdr);
1374 ehdr->e_phnum = numsegs + 1;
1375 ehdr->e_shentsize = sizeof(Elf_Shdr);
1377 ehdr->e_shstrndx = SHN_UNDEF;
1379 if (error == 0 && phdr != NULL) {
1381 * Fill in the program header entries.
1383 struct phdr_closure phc;
1385 /* The note segement. */
1386 phdr->p_type = PT_NOTE;
1387 phdr->p_offset = noteoff;
1390 phdr->p_filesz = notesz;
1396 /* All the writable segments from the program. */
1398 phc.phdr_max = phdr + numsegs;
1399 phc.offset = target->off;
1400 each_segment(p, cb_put_phdr, &phc, 1);
1406 * Append core dump notes to target ELF buffer or simply update target size
1407 * if dryrun selected.
1410 elf_putallnotes(struct lwp *corelp, elf_buf_t target, int sig,
1413 struct proc *p = corelp->lwp_proc;
1417 prfpregset_t fpregs;
1421 prfpregset_t *fpregs;
1426 * Allocate temporary storage for notes on heap to avoid stack overflow.
1428 if (mode != DRYRUN) {
1429 tmpdata = kmalloc(sizeof(*tmpdata), M_TEMP, M_ZERO | M_WAITOK);
1430 status = &tmpdata->status;
1431 fpregs = &tmpdata->fpregs;
1432 psinfo = &tmpdata->psinfo;
1441 * Append LWP-agnostic note.
1443 if (mode != DRYRUN) {
1444 psinfo->pr_version = PRPSINFO_VERSION;
1445 psinfo->pr_psinfosz = sizeof(prpsinfo_t);
1446 strlcpy(psinfo->pr_fname, p->p_comm,
1447 sizeof(psinfo->pr_fname));
1449 * XXX - We don't fill in the command line arguments
1452 strlcpy(psinfo->pr_psargs, p->p_comm,
1453 sizeof(psinfo->pr_psargs));
1456 __elfN(putnote)(target, "CORE", NT_PRPSINFO, psinfo, sizeof *psinfo);
1461 * Append first note for LWP that triggered core so that it is
1462 * the selected one when the debugger starts.
1464 if (mode != DRYRUN) {
1465 status->pr_version = PRSTATUS_VERSION;
1466 status->pr_statussz = sizeof(prstatus_t);
1467 status->pr_gregsetsz = sizeof(gregset_t);
1468 status->pr_fpregsetsz = sizeof(fpregset_t);
1469 status->pr_osreldate = osreldate;
1470 status->pr_cursig = sig;
1471 status->pr_pid = corelp->lwp_tid;
1472 fill_regs(corelp, &status->pr_reg);
1473 fill_fpregs(corelp, fpregs);
1476 __elfN(putnote)(target, "CORE", NT_PRSTATUS, status, sizeof *status);
1480 __elfN(putnote)(target, "CORE", NT_FPREGSET, fpregs, sizeof *fpregs);
1485 * Then append notes for other LWPs.
1487 FOREACH_LWP_IN_PROC(lp, p) {
1490 /* skip lwps being created */
1491 if (lp->lwp_thread == NULL)
1493 if (mode != DRYRUN) {
1494 status->pr_pid = lp->lwp_tid;
1495 fill_regs(lp, &status->pr_reg);
1496 fill_fpregs(lp, fpregs);
1498 error = __elfN(putnote)(target, "CORE", NT_PRSTATUS,
1499 status, sizeof *status);
1502 error = __elfN(putnote)(target, "CORE", NT_FPREGSET,
1503 fpregs, sizeof *fpregs);
1509 if (tmpdata != NULL)
1510 kfree(tmpdata, M_TEMP);
1515 * Generate a note sub-structure.
1517 * NOTE: 4-byte alignment.
1520 __elfN(putnote)(elf_buf_t target, const char *name, int type,
1521 const void *desc, size_t descsz)
1527 note.n_namesz = strlen(name) + 1;
1528 note.n_descsz = descsz;
1530 dst = target_reserve(target, sizeof(note), &error);
1532 bcopy(¬e, dst, sizeof note);
1533 dst = target_reserve(target, note.n_namesz, &error);
1535 bcopy(name, dst, note.n_namesz);
1536 target->off = roundup2(target->off, sizeof(Elf_Word));
1537 dst = target_reserve(target, note.n_descsz, &error);
1539 bcopy(desc, dst, note.n_descsz);
1540 target->off = roundup2(target->off, sizeof(Elf_Word));
1546 elf_putsigs(struct lwp *lp, elf_buf_t target)
1548 /* XXX lwp handle more than one lwp */
1549 struct proc *p = lp->lwp_proc;
1551 struct ckpt_siginfo *csi;
1553 csi = target_reserve(target, sizeof(struct ckpt_siginfo), &error);
1555 csi->csi_ckptpisz = sizeof(struct ckpt_siginfo);
1556 bcopy(p->p_sigacts, &csi->csi_sigacts, sizeof(*p->p_sigacts));
1557 bcopy(&p->p_realtimer, &csi->csi_itimerval, sizeof(struct itimerval));
1558 bcopy(&lp->lwp_sigmask, &csi->csi_sigmask,
1560 csi->csi_sigparent = p->p_sigparent;
1566 elf_putfiles(struct proc *p, elf_buf_t target, struct file *ckfp)
1568 thread_t td = curthread;
1571 struct ckpt_filehdr *cfh = NULL;
1572 struct ckpt_fileinfo *cfi;
1577 * the duplicated loop is gross, but it was the only way
1578 * to eliminate uninitialized variable warnings
1580 cfh = target_reserve(target, sizeof(struct ckpt_filehdr), &error);
1582 cfh->cfh_nfiles = 0;
1586 * ignore STDIN/STDERR/STDOUT.
1588 KKASSERT(td->td_proc == p);
1589 for (i = 3; error == 0 && i < p->p_fd->fd_nfiles; i++) {
1590 fp = holdfp(td, i, -1);
1594 * XXX Only checkpoint vnodes for now.
1596 if (fp->f_type != DTYPE_VNODE) {
1600 cfi = target_reserve(target, sizeof(struct ckpt_fileinfo),
1606 cfi->cfi_index = -1;
1607 cfi->cfi_type = fp->f_type;
1608 cfi->cfi_flags = fp->f_flag;
1609 cfi->cfi_offset = fp->f_offset;
1610 cfi->cfi_ckflags = 0;
1613 cfi->cfi_ckflags |= CKFIF_ISCKPTFD;
1614 /* f_count and f_msgcount should not be saved/restored */
1615 /* XXX save cred info */
1617 switch(fp->f_type) {
1619 vp = (struct vnode *)fp->f_data;
1621 * it looks like a bug in ptrace is marking
1622 * a non-vnode as a vnode - until we find the
1623 * root cause this will at least prevent
1624 * further panics from truss
1626 if (vp == NULL || vp->v_mount == NULL)
1630 cfi->cfi_fh.fh_fsid = vp->v_mount->mnt_stat.f_fsid;
1631 error = VFS_VPTOFH(vp, &cfi->cfi_fh.fh_fid);
1642 elf_puttextvp(struct proc *p, elf_buf_t target)
1646 struct fp_closure fpc;
1647 struct ckpt_vminfo *vminfo;
1649 vminfo = target_reserve(target, sizeof(struct ckpt_vminfo), &error);
1650 if (vminfo != NULL) {
1651 vminfo->cvm_dsize = btoc(p->p_vmspace->vm_dsize); /* pages */
1652 vminfo->cvm_tsize = btoc(p->p_vmspace->vm_tsize); /* pages */
1653 vminfo->cvm_daddr = p->p_vmspace->vm_daddr;
1654 vminfo->cvm_taddr = p->p_vmspace->vm_taddr;
1658 vn_count = target_reserve(target, sizeof(int), &error);
1659 if (target->buf != NULL) {
1660 fpc.vnh = (struct vn_hdr *)(target->buf + target->off);
1661 fpc.vnh_max = fpc.vnh +
1662 (target->off_max - target->off) / sizeof(struct vn_hdr);
1663 error = each_segment(p, cb_put_fp, &fpc, 0);
1665 *vn_count = fpc.count;
1667 error = each_segment(p, cb_fpcount_segment, &fpc.count, 0);
1669 target->off += fpc.count * sizeof(struct vn_hdr);
1674 * Try to find the appropriate ABI-note section for checknote,
1675 * The entire image is searched if necessary, not only the first page.
1678 __elfN(check_note)(struct image_params *imgp, Elf_Brandnote *checknote,
1681 boolean_t valid_note_found;
1682 const Elf_Phdr *phdr, *pnote;
1683 const Elf_Ehdr *hdr;
1686 valid_note_found = FALSE;
1687 hdr = (const Elf_Ehdr *)imgp->image_header;
1688 phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff);
1690 for (i = 0; i < hdr->e_phnum; i++) {
1691 if (phdr[i].p_type == PT_NOTE) {
1693 valid_note_found = check_PT_NOTE (imgp, checknote,
1695 if (valid_note_found)
1699 return valid_note_found;
1703 * Be careful not to create new overflow conditions when checking
1707 note_overflow(const Elf_Note *note, size_t maxsize)
1709 if (sizeof(*note) > maxsize)
1711 if (note->n_namesz > maxsize - sizeof(*note))
1717 hdr_overflow(__ElfN(Off) off_beg, __ElfN(Size) size)
1719 __ElfN(Off) off_end;
1721 off_end = off_beg + size;
1722 if (off_end < off_beg)
1728 check_PT_NOTE(struct image_params *imgp, Elf_Brandnote *checknote,
1729 int32_t *osrel, const Elf_Phdr * pnote)
1731 boolean_t limited_to_first_page;
1732 boolean_t found = FALSE;
1733 const Elf_Note *note, *note0, *note_end;
1734 const char *note_name;
1735 __ElfN(Off) noteloc, firstloc;
1736 __ElfN(Size) notesz, firstlen, endbyte;
1738 struct lwbuf lwb_cache;
1743 if (hdr_overflow(pnote->p_offset, pnote->p_filesz))
1745 notesz = pnote->p_filesz;
1746 noteloc = pnote->p_offset;
1747 endbyte = noteloc + notesz;
1748 limited_to_first_page = noteloc < PAGE_SIZE && endbyte < PAGE_SIZE;
1750 if (limited_to_first_page) {
1751 note = (const Elf_Note *)(imgp->image_header + noteloc);
1752 note_end = (const Elf_Note *)(imgp->image_header + endbyte);
1755 firstloc = noteloc & PAGE_MASK;
1756 firstlen = PAGE_SIZE - firstloc;
1757 if (notesz < sizeof(Elf_Note) || notesz > PAGE_SIZE)
1761 if (exec_map_page(imgp, noteloc >> PAGE_SHIFT, &lwb, &page))
1763 if (firstlen < notesz) { /* crosses page boundary */
1764 data = kmalloc(notesz, M_TEMP, M_WAITOK);
1765 bcopy(page + firstloc, data, firstlen);
1767 exec_unmap_page(lwb);
1769 if (exec_map_page(imgp, (noteloc >> PAGE_SHIFT) + 1,
1771 kfree(data, M_TEMP);
1774 bcopy(page, data + firstlen, notesz - firstlen);
1775 note = note0 = (const Elf_Note *)(data);
1776 note_end = (const Elf_Note *)(data + notesz);
1778 note = note0 = (const Elf_Note *)(page + firstloc);
1779 note_end = (const Elf_Note *)(page + firstloc +
1784 for (n = 0; n < 100 && note >= note0 && note < note_end; n++) {
1785 if (!aligned(note, Elf32_Addr))
1787 if (note_overflow(note, (const char *)note_end -
1788 (const char *)note)) {
1791 note_name = (const char *)(note + 1);
1793 if (note->n_namesz == checknote->hdr.n_namesz
1794 && note->n_descsz == checknote->hdr.n_descsz
1795 && note->n_type == checknote->hdr.n_type
1796 && (strncmp(checknote->vendor, note_name,
1797 checknote->hdr.n_namesz) == 0)) {
1798 /* Fetch osreldata from ABI.note-tag */
1799 if ((checknote->flags & BN_TRANSLATE_OSREL) != 0 &&
1800 checknote->trans_osrel != NULL)
1801 checknote->trans_osrel(note, osrel);
1805 note = (const Elf_Note *)((const char *)(note + 1) +
1806 roundup2(note->n_namesz, sizeof(Elf32_Addr)) +
1807 roundup2(note->n_descsz, sizeof(Elf32_Addr)));
1810 if (!limited_to_first_page) {
1812 kfree(data, M_TEMP);
1813 exec_unmap_page(lwb);
1819 * The interpreter program header may be located beyond the first page, so
1820 * regardless of its location, a copy of the interpreter path is created so
1821 * that it may be safely referenced by the calling function in all case. The
1822 * memory is allocated by calling function, and the copying is done here.
1825 extract_interpreter(struct image_params *imgp, const Elf_Phdr *pinterpreter,
1828 boolean_t limited_to_first_page;
1829 const boolean_t result_success = FALSE;
1830 const boolean_t result_failure = TRUE;
1831 __ElfN(Off) pathloc, firstloc;
1832 __ElfN(Size) pathsz, firstlen, endbyte;
1834 struct lwbuf lwb_cache;
1837 if (hdr_overflow(pinterpreter->p_offset, pinterpreter->p_filesz))
1838 return (result_failure);
1839 pathsz = pinterpreter->p_filesz;
1840 pathloc = pinterpreter->p_offset;
1841 endbyte = pathloc + pathsz;
1843 limited_to_first_page = pathloc < PAGE_SIZE && endbyte < PAGE_SIZE;
1844 if (limited_to_first_page) {
1845 bcopy(imgp->image_header + pathloc, data, pathsz);
1846 return (result_success);
1849 firstloc = pathloc & PAGE_MASK;
1850 firstlen = PAGE_SIZE - firstloc;
1853 if (exec_map_page(imgp, pathloc >> PAGE_SHIFT, &lwb, &page))
1854 return (result_failure);
1856 if (firstlen < pathsz) { /* crosses page boundary */
1857 bcopy(page + firstloc, data, firstlen);
1859 exec_unmap_page(lwb);
1861 if (exec_map_page(imgp, (pathloc >> PAGE_SHIFT) + 1, &lwb,
1863 return (result_failure);
1864 bcopy(page, data + firstlen, pathsz - firstlen);
1866 bcopy(page + firstloc, data, pathsz);
1868 exec_unmap_page(lwb);
1869 return (result_success);
1873 __elfN(bsd_trans_osrel)(const Elf_Note *note, int32_t *osrel)
1877 p = (uintptr_t)(note + 1);
1878 p += roundup2(note->n_namesz, sizeof(Elf32_Addr));
1879 *osrel = *(const int32_t *)(p);
1885 * Tell kern_execve.c about it, with a little help from the linker.
1887 #if defined(__x86_64__)
1888 static struct execsw elf_execsw = {exec_elf64_imgact, "ELF64"};
1889 EXEC_SET_ORDERED(elf64, elf_execsw, SI_ORDER_FIRST);
1890 #else /* i386 assumed */
1891 static struct execsw elf_execsw = {exec_elf32_imgact, "ELF32"};
1892 EXEC_SET_ORDERED(elf32, elf_execsw, SI_ORDER_FIRST);
1896 __elfN(trans_prot)(Elf_Word flags)
1902 prot |= VM_PROT_EXECUTE;
1904 prot |= VM_PROT_WRITE;
1906 prot |= VM_PROT_READ;
1911 __elfN(untrans_prot)(vm_prot_t prot)
1916 if (prot & VM_PROT_EXECUTE)
1918 if (prot & VM_PROT_READ)
1920 if (prot & VM_PROT_WRITE)
1926 pie_base_hint(struct proc *p)
1930 if (elf_pie_base_mmap)
1931 base = vm_map_hint(p, 0, VM_PROT_READ | VM_PROT_EXECUTE);
1933 base = ET_DYN_LOAD_ADDR;