2 * Copyright (c) 1993, David Greenman
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
30 #include "opt_hwpmc_hooks.h"
31 #include "opt_ktrace.h"
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/eventhandler.h>
38 #include <sys/mutex.h>
39 #include <sys/sysproto.h>
40 #include <sys/signalvar.h>
41 #include <sys/kernel.h>
42 #include <sys/mount.h>
43 #include <sys/filedesc.h>
44 #include <sys/fcntl.h>
47 #include <sys/imgact.h>
48 #include <sys/imgact_elf.h>
50 #include <sys/malloc.h>
53 #include <sys/pioctl.h>
54 #include <sys/namei.h>
55 #include <sys/resourcevar.h>
56 #include <sys/sf_buf.h>
57 #include <sys/syscallsubr.h>
58 #include <sys/sysent.h>
60 #include <sys/sysctl.h>
61 #include <sys/vnode.h>
63 #include <sys/ktrace.h>
67 #include <vm/vm_param.h>
69 #include <vm/vm_page.h>
70 #include <vm/vm_map.h>
71 #include <vm/vm_kern.h>
72 #include <vm/vm_extern.h>
73 #include <vm/vm_object.h>
74 #include <vm/vm_pager.h>
77 #include <sys/pmckern.h>
80 #include <machine/reg.h>
82 #include <security/audit/audit.h>
83 #include <security/mac/mac_framework.h>
85 MALLOC_DEFINE(M_PARGS, "proc-args", "Process arguments");
87 static int sysctl_kern_ps_strings(SYSCTL_HANDLER_ARGS);
88 static int sysctl_kern_usrstack(SYSCTL_HANDLER_ARGS);
89 static int sysctl_kern_stackprot(SYSCTL_HANDLER_ARGS);
90 static int do_execve(struct thread *td, struct image_args *args,
92 static void exec_free_args(struct image_args *);
94 /* XXX This should be vm_size_t. */
95 SYSCTL_PROC(_kern, KERN_PS_STRINGS, ps_strings, CTLTYPE_ULONG|CTLFLAG_RD,
96 NULL, 0, sysctl_kern_ps_strings, "LU", "");
98 /* XXX This should be vm_size_t. */
99 SYSCTL_PROC(_kern, KERN_USRSTACK, usrstack, CTLTYPE_ULONG|CTLFLAG_RD,
100 NULL, 0, sysctl_kern_usrstack, "LU", "");
102 SYSCTL_PROC(_kern, OID_AUTO, stackprot, CTLTYPE_INT|CTLFLAG_RD,
103 NULL, 0, sysctl_kern_stackprot, "I", "");
105 u_long ps_arg_cache_limit = PAGE_SIZE / 16;
106 SYSCTL_ULONG(_kern, OID_AUTO, ps_arg_cache_limit, CTLFLAG_RW,
107 &ps_arg_cache_limit, 0, "");
110 sysctl_kern_ps_strings(SYSCTL_HANDLER_ARGS)
117 if (req->flags & SCTL_MASK32) {
119 val = (unsigned int)p->p_sysent->sv_psstrings;
120 error = SYSCTL_OUT(req, &val, sizeof(val));
123 error = SYSCTL_OUT(req, &p->p_sysent->sv_psstrings,
124 sizeof(p->p_sysent->sv_psstrings));
129 sysctl_kern_usrstack(SYSCTL_HANDLER_ARGS)
136 if (req->flags & SCTL_MASK32) {
138 val = (unsigned int)p->p_sysent->sv_usrstack;
139 error = SYSCTL_OUT(req, &val, sizeof(val));
142 error = SYSCTL_OUT(req, &p->p_sysent->sv_usrstack,
143 sizeof(p->p_sysent->sv_usrstack));
148 sysctl_kern_stackprot(SYSCTL_HANDLER_ARGS)
153 return (SYSCTL_OUT(req, &p->p_sysent->sv_stackprot,
154 sizeof(p->p_sysent->sv_stackprot)));
158 * Each of the items is a pointer to a `const struct execsw', hence the
159 * double pointer here.
161 static const struct execsw **execsw;
163 #ifndef _SYS_SYSPROTO_H_
177 struct execve_args /* {
184 struct image_args args;
186 error = exec_copyin_args(&args, uap->fname, UIO_USERSPACE,
187 uap->argv, uap->envv);
189 error = kern_execve(td, &args, NULL);
193 #ifndef _SYS_SYSPROTO_H_
194 struct __mac_execve_args {
206 __mac_execve(td, uap)
208 struct __mac_execve_args /* {
217 struct image_args args;
219 error = exec_copyin_args(&args, uap->fname, UIO_USERSPACE,
220 uap->argv, uap->envv);
222 error = kern_execve(td, &args, uap->mac_p);
230 * XXX: kern_execve has the astonishing property of not always
231 * returning to the caller. If sufficiently bad things happen during
232 * the call to do_execve(), it can end up calling exit1(); as a result,
233 * callers must avoid doing anything which they might need to undo
234 * (e.g., allocating memory).
237 kern_execve(td, args, mac_p)
239 struct image_args *args;
242 struct proc *p = td->td_proc;
245 AUDIT_ARG(argv, args->begin_argv, args->argc,
246 args->begin_envv - args->begin_argv);
247 AUDIT_ARG(envv, args->begin_envv, args->envc,
248 args->endp - args->begin_envv);
249 if (p->p_flag & P_HADTHREADS) {
251 if (thread_single(SINGLE_BOUNDARY)) {
253 exec_free_args(args);
254 return (ERESTART); /* Try again later. */
259 error = do_execve(td, args, mac_p);
261 if (p->p_flag & P_HADTHREADS) {
264 * If success, we upgrade to SINGLE_EXIT state to
265 * force other threads to suicide.
268 thread_single(SINGLE_EXIT);
278 * In-kernel implementation of execve(). All arguments are assumed to be
279 * userspace pointers from the passed thread.
284 do_execve(td, args, mac_p)
286 struct image_args *args;
289 struct proc *p = td->td_proc;
290 struct nameidata nd, *ndp;
291 struct ucred *newcred = NULL, *oldcred;
292 struct uidinfo *euip;
293 register_t *stack_base;
295 struct image_params image_params, *imgp;
297 int (*img_first)(struct image_params *);
298 struct pargs *oldargs = NULL, *newargs = NULL;
299 struct sigacts *oldsigacts, *newsigacts;
301 struct vnode *tracevp = NULL;
302 struct ucred *tracecred = NULL;
304 struct vnode *textvp = NULL;
305 int credential_changing;
309 struct label *interplabel = NULL;
313 struct pmckern_procexec pe;
317 imgp = &image_params;
320 * Lock the process and set the P_INEXEC flag to indicate that
321 * it should be left alone until we're done here. This is
322 * necessary to avoid race conditions - e.g. in ptrace() -
323 * that might allow a local user to illicitly obtain elevated
327 KASSERT((p->p_flag & P_INEXEC) == 0,
328 ("%s(): process already has P_INEXEC flag", __func__));
329 p->p_flag |= P_INEXEC;
333 * Initialize part of the common data
336 imgp->execlabel = NULL;
338 imgp->entry_addr = 0;
339 imgp->vmspace_destroyed = 0;
340 imgp->interpreted = 0;
341 imgp->interpreter_name = args->buf + PATH_MAX + ARG_MAX;
342 imgp->auxargs = NULL;
345 imgp->firstpage = NULL;
346 imgp->ps_strings = 0;
347 imgp->auxarg_size = 0;
351 error = mac_execve_enter(imgp, mac_p);
356 imgp->image_header = NULL;
359 * Translate the file name. namei() returns a vnode pointer
360 * in ni_vp amoung other things.
362 * XXXAUDIT: It would be desirable to also audit the name of the
363 * interpreter if this is an interpreted binary.
366 NDINIT(ndp, LOOKUP, ISOPEN | LOCKLEAF | FOLLOW | SAVENAME | MPSAFE |
367 AUDITVNODE1, UIO_SYSSPACE, args->fname, td);
374 vfslocked = NDHASGIANT(ndp);
375 imgp->vp = ndp->ni_vp;
378 * Check file permissions (also 'opens' file)
380 error = exec_check_permissions(imgp);
382 goto exec_fail_dealloc;
384 imgp->object = imgp->vp->v_object;
385 if (imgp->object != NULL)
386 vm_object_reference(imgp->object);
389 * Set VV_TEXT now so no one can write to the executable while we're
392 * Remember if this was set before and unset it in case this is not
393 * actually an executable image.
395 textset = imgp->vp->v_vflag & VV_TEXT;
396 imgp->vp->v_vflag |= VV_TEXT;
398 error = exec_map_first_page(imgp);
400 goto exec_fail_dealloc;
403 * If the current process has a special image activator it
404 * wants to try first, call it. For example, emulating shell
405 * scripts differently.
408 if ((img_first = imgp->proc->p_sysent->sv_imgact_try) != NULL)
409 error = img_first(imgp);
412 * Loop through the list of image activators, calling each one.
413 * An activator returns -1 if there is no match, 0 on success,
414 * and an error otherwise.
416 for (i = 0; error == -1 && execsw[i]; ++i) {
417 if (execsw[i]->ex_imgact == NULL ||
418 execsw[i]->ex_imgact == img_first) {
421 error = (*execsw[i]->ex_imgact)(imgp);
427 imgp->vp->v_vflag &= ~VV_TEXT;
430 goto exec_fail_dealloc;
434 * Special interpreter operation, cleanup and loop up to try to
435 * activate the interpreter.
437 if (imgp->interpreted) {
438 exec_unmap_first_page(imgp);
440 * VV_TEXT needs to be unset for scripts. There is a short
441 * period before we determine that something is a script where
442 * VV_TEXT will be set. The vnode lock is held over this
443 * entire period so nothing should illegitimately be blocked.
445 imgp->vp->v_vflag &= ~VV_TEXT;
446 /* free name buffer and old vnode */
447 NDFREE(ndp, NDF_ONLY_PNBUF);
449 interplabel = mac_vnode_label_alloc();
450 mac_copy_vnode_label(ndp->ni_vp->v_label, interplabel);
453 vm_object_deallocate(imgp->object);
455 VFS_UNLOCK_GIANT(vfslocked);
457 /* set new name to that of the interpreter */
458 NDINIT(ndp, LOOKUP, LOCKLEAF | FOLLOW | SAVENAME | MPSAFE,
459 UIO_SYSSPACE, imgp->interpreter_name, td);
464 * Copy out strings (args and env) and initialize stack base
466 if (p->p_sysent->sv_copyout_strings)
467 stack_base = (*p->p_sysent->sv_copyout_strings)(imgp);
469 stack_base = exec_copyout_strings(imgp);
472 * If custom stack fixup routine present for this process
473 * let it do the stack setup.
474 * Else stuff argument count as first item on stack
476 if (p->p_sysent->sv_fixup != NULL)
477 (*p->p_sysent->sv_fixup)(&stack_base, imgp);
479 suword(--stack_base, imgp->args->argc);
482 * For security and other reasons, the file descriptor table cannot
483 * be shared after an exec.
488 * Malloc things before we need locks.
491 euip = uifind(attr.va_uid);
492 i = imgp->args->begin_envv - imgp->args->begin_argv;
493 /* Cache arguments if they fit inside our allowance */
494 if (ps_arg_cache_limit >= i + sizeof(struct pargs)) {
495 newargs = pargs_alloc(i);
496 bcopy(imgp->args->begin_argv, newargs->ar_args, i);
499 /* close files on exec */
500 VOP_UNLOCK(imgp->vp, 0, td);
502 vn_lock(imgp->vp, LK_EXCLUSIVE | LK_RETRY, td);
504 /* Get a reference to the vnode prior to locking the proc */
508 * For security and other reasons, signal handlers cannot
509 * be shared after an exec. The new process gets a copy of the old
510 * handlers. In execsigs(), the new process will have its signals
514 if (sigacts_shared(p->p_sigacts)) {
515 oldsigacts = p->p_sigacts;
517 newsigacts = sigacts_alloc();
518 sigacts_copy(newsigacts, oldsigacts);
520 p->p_sigacts = newsigacts;
527 /* reset caught signals */
530 /* name this process - nameiexec(p, ndp) */
531 len = min(ndp->ni_cnd.cn_namelen,MAXCOMLEN);
532 bcopy(ndp->ni_cnd.cn_nameptr, p->p_comm, len);
536 * mark as execed, wakeup the process that vforked (if any) and tell
537 * it that it now has its own resources back
540 if (p->p_pptr && (p->p_flag & P_PPWAIT)) {
541 p->p_flag &= ~P_PPWAIT;
546 * Implement image setuid/setgid.
548 * Don't honor setuid/setgid if the filesystem prohibits it or if
549 * the process is being traced.
551 * XXXMAC: For the time being, use NOSUID to also prohibit
552 * transitions on the file system.
554 oldcred = p->p_ucred;
555 credential_changing = 0;
556 credential_changing |= (attr.va_mode & VSUID) && oldcred->cr_uid !=
558 credential_changing |= (attr.va_mode & VSGID) && oldcred->cr_gid !=
561 will_transition = mac_execve_will_transition(oldcred, imgp->vp,
563 credential_changing |= will_transition;
566 if (credential_changing &&
567 (imgp->vp->v_mount->mnt_flag & MNT_NOSUID) == 0 &&
568 (p->p_flag & P_TRACED) == 0) {
570 * Turn off syscall tracing for set-id programs, except for
571 * root. Record any set-id flags first to make sure that
572 * we do not regain any tracing during a possible block.
577 if (p->p_tracevp != NULL &&
578 priv_check_cred(oldcred, PRIV_DEBUG_DIFFCRED,
580 mtx_lock(&ktrace_mtx);
582 tracevp = p->p_tracevp;
584 tracecred = p->p_tracecred;
585 p->p_tracecred = NULL;
586 mtx_unlock(&ktrace_mtx);
590 * Close any file descriptors 0..2 that reference procfs,
591 * then make sure file descriptors 0..2 are in use.
593 * setugidsafety() may call closef() and then pfind()
594 * which may grab the process lock.
595 * fdcheckstd() may call falloc() which may block to
596 * allocate memory, so temporarily drop the process lock.
600 VOP_UNLOCK(imgp->vp, 0, td);
601 error = fdcheckstd(td);
602 vn_lock(imgp->vp, LK_EXCLUSIVE | LK_RETRY, td);
607 * Set the new credentials.
609 crcopy(newcred, oldcred);
610 if (attr.va_mode & VSUID)
611 change_euid(newcred, euip);
612 if (attr.va_mode & VSGID)
613 change_egid(newcred, attr.va_gid);
615 if (will_transition) {
616 mac_execve_transition(oldcred, newcred, imgp->vp,
621 * Implement correct POSIX saved-id behavior.
623 * XXXMAC: Note that the current logic will save the
624 * uid and gid if a MAC domain transition occurs, even
625 * though maybe it shouldn't.
627 change_svuid(newcred, newcred->cr_uid);
628 change_svgid(newcred, newcred->cr_gid);
629 p->p_ucred = newcred;
632 if (oldcred->cr_uid == oldcred->cr_ruid &&
633 oldcred->cr_gid == oldcred->cr_rgid)
634 p->p_flag &= ~P_SUGID;
636 * Implement correct POSIX saved-id behavior.
638 * XXX: It's not clear that the existing behavior is
639 * POSIX-compliant. A number of sources indicate that the
640 * saved uid/gid should only be updated if the new ruid is
641 * not equal to the old ruid, or the new euid is not equal
642 * to the old euid and the new euid is not equal to the old
643 * ruid. The FreeBSD code always updates the saved uid/gid.
644 * Also, this code uses the new (replaced) euid and egid as
645 * the source, which may or may not be the right ones to use.
647 if (oldcred->cr_svuid != oldcred->cr_uid ||
648 oldcred->cr_svgid != oldcred->cr_gid) {
649 crcopy(newcred, oldcred);
650 change_svuid(newcred, newcred->cr_uid);
651 change_svgid(newcred, newcred->cr_gid);
652 p->p_ucred = newcred;
658 * Store the vp for use in procfs. This vnode was referenced prior
659 * to locking the proc lock.
661 textvp = p->p_textvp;
662 p->p_textvp = ndp->ni_vp;
665 * Notify others that we exec'd, and clear the P_INEXEC flag
666 * as we're now a bona fide freshly-execed process.
668 KNOTE_LOCKED(&p->p_klist, NOTE_EXEC);
669 p->p_flag &= ~P_INEXEC;
672 * If tracing the process, trap to debugger so breakpoints
673 * can be set before the program executes.
674 * Use tdsignal to deliver signal to current thread, use
675 * psignal may cause the signal to be delivered to wrong thread
676 * because that thread will exit, remember we are going to enter
677 * single thread mode.
679 if (p->p_flag & P_TRACED)
680 tdsignal(p, td, SIGTRAP, NULL);
682 /* clear "fork but no exec" flag, as we _are_ execing */
683 p->p_acflag &= ~AFORK;
686 * Free any previous argument cache and replace it with
687 * the new argument cache, if any.
695 * Check if system-wide sampling is in effect or if the
696 * current process is using PMCs. If so, do exec() time
697 * processing. This processing needs to happen AFTER the
698 * P_INEXEC flag is cleared.
700 * The proc lock needs to be released before taking the PMC
703 if (PMC_SYSTEM_SAMPLING_ACTIVE() || PMC_PROC_IS_USING_PMCS(p)) {
705 pe.pm_credentialschanged = credential_changing;
706 pe.pm_entryaddr = imgp->entry_addr;
708 PMC_CALL_HOOK_X(td, PMC_FN_PROCESS_EXEC, (void *) &pe);
711 #else /* !HWPMC_HOOKS */
715 /* Set values passed into the program in registers. */
716 if (p->p_sysent->sv_setregs)
717 (*p->p_sysent->sv_setregs)(td, imgp->entry_addr,
718 (u_long)(uintptr_t)stack_base, imgp->ps_strings);
720 exec_setregs(td, imgp->entry_addr,
721 (u_long)(uintptr_t)stack_base, imgp->ps_strings);
723 vfs_mark_atime(imgp->vp, td);
727 * Free any resources malloc'd earlier that we didn't use.
734 VOP_UNLOCK(imgp->vp, 0, td);
736 * Handle deferred decrement of ref counts.
738 if (textvp != NULL) {
741 tvfslocked = VFS_LOCK_GIANT(textvp->v_mount);
743 VFS_UNLOCK_GIANT(tvfslocked);
745 if (ndp->ni_vp && error != 0)
750 if (tracecred != NULL)
753 vn_lock(imgp->vp, LK_EXCLUSIVE | LK_RETRY, td);
758 if (oldsigacts != NULL)
759 sigacts_free(oldsigacts);
764 * free various allocated resources
766 if (imgp->firstpage != NULL)
767 exec_unmap_first_page(imgp);
769 if (imgp->vp != NULL) {
770 NDFREE(ndp, NDF_ONLY_PNBUF);
774 if (imgp->object != NULL)
775 vm_object_deallocate(imgp->object);
779 * Stop the process here if its stop event mask has
780 * the S_EXEC bit set.
782 STOPEVENT(p, S_EXEC, 0);
787 /* we're done here, clear P_INEXEC */
789 p->p_flag &= ~P_INEXEC;
794 mac_execve_exit(imgp);
795 if (interplabel != NULL)
796 mac_vnode_label_free(interplabel);
798 VFS_UNLOCK_GIANT(vfslocked);
799 exec_free_args(args);
801 if (error && imgp->vmspace_destroyed) {
802 /* sorry, no more process anymore. exit gracefully */
803 exit1(td, W_EXITCODE(0, SIGABRT));
810 exec_map_first_page(imgp)
811 struct image_params *imgp;
815 vm_page_t ma[VM_INITIAL_PAGEIN];
818 if (imgp->firstpage != NULL)
819 exec_unmap_first_page(imgp);
821 object = imgp->vp->v_object;
824 VM_OBJECT_LOCK(object);
825 ma[0] = vm_page_grab(object, 0, VM_ALLOC_NORMAL | VM_ALLOC_RETRY);
826 if ((ma[0]->valid & VM_PAGE_BITS_ALL) != VM_PAGE_BITS_ALL) {
827 initial_pagein = VM_INITIAL_PAGEIN;
828 if (initial_pagein > object->size)
829 initial_pagein = object->size;
830 for (i = 1; i < initial_pagein; i++) {
831 if ((ma[i] = vm_page_lookup(object, i)) != NULL) {
834 if ((ma[i]->oflags & VPO_BUSY) || ma[i]->busy)
838 ma[i] = vm_page_alloc(object, i,
845 rv = vm_pager_get_pages(object, ma, initial_pagein, 0);
846 ma[0] = vm_page_lookup(object, 0);
847 if ((rv != VM_PAGER_OK) || (ma[0] == NULL) ||
848 (ma[0]->valid == 0)) {
850 vm_page_lock_queues();
852 vm_page_unlock_queues();
854 VM_OBJECT_UNLOCK(object);
858 vm_page_lock_queues();
860 vm_page_unlock_queues();
861 vm_page_wakeup(ma[0]);
862 VM_OBJECT_UNLOCK(object);
864 imgp->firstpage = sf_buf_alloc(ma[0], 0);
865 imgp->image_header = (char *)sf_buf_kva(imgp->firstpage);
871 exec_unmap_first_page(imgp)
872 struct image_params *imgp;
876 if (imgp->firstpage != NULL) {
877 m = sf_buf_page(imgp->firstpage);
878 sf_buf_free(imgp->firstpage);
879 imgp->firstpage = NULL;
880 vm_page_lock_queues();
882 vm_page_unlock_queues();
887 * Destroy old address space, and allocate a new stack
888 * The new stack is only SGROWSIZ large because it is grown
889 * automatically in trap.c.
892 exec_new_vmspace(imgp, sv)
893 struct image_params *imgp;
894 struct sysentvec *sv;
897 struct proc *p = imgp->proc;
898 struct vmspace *vmspace = p->p_vmspace;
899 vm_offset_t stack_addr;
902 imgp->vmspace_destroyed = 1;
905 /* Called with Giant held, do not depend on it! */
906 EVENTHANDLER_INVOKE(process_exec, p, imgp);
909 * Here is as good a place as any to do any resource limit cleanups.
910 * This is needed if a 64 bit binary exec's a 32 bit binary - the
911 * data size limit may need to be changed to a value that makes
912 * sense for the 32 bit binary.
914 if (sv->sv_fixlimits != NULL)
918 * Blow away entire process VM, if address space not shared,
919 * otherwise, create a new VM space so that other threads are
922 map = &vmspace->vm_map;
923 if (vmspace->vm_refcnt == 1 && vm_map_min(map) == sv->sv_minuser &&
924 vm_map_max(map) == sv->sv_maxuser) {
926 pmap_remove_pages(vmspace_pmap(vmspace));
927 vm_map_remove(map, vm_map_min(map), vm_map_max(map));
929 vmspace_exec(p, sv->sv_minuser, sv->sv_maxuser);
930 vmspace = p->p_vmspace;
931 map = &vmspace->vm_map;
934 /* Allocate a new stack */
935 stack_addr = sv->sv_usrstack - maxssiz;
936 error = vm_map_stack(map, stack_addr, (vm_size_t)maxssiz,
937 sv->sv_stackprot, VM_PROT_ALL, MAP_STACK_GROWS_DOWN);
942 /* Allocate a new register stack */
943 stack_addr = IA64_BACKINGSTORE;
944 error = vm_map_stack(map, stack_addr, (vm_size_t)maxssiz,
945 sv->sv_stackprot, VM_PROT_ALL, MAP_STACK_GROWS_UP);
950 /* vm_ssize and vm_maxsaddr are somewhat antiquated concepts in the
951 * VM_STACK case, but they are still used to monitor the size of the
952 * process stack so we can check the stack rlimit.
954 vmspace->vm_ssize = sgrowsiz >> PAGE_SHIFT;
955 vmspace->vm_maxsaddr = (char *)sv->sv_usrstack - maxssiz;
961 * Copy out argument and environment strings from the old process
962 * address space into the temporary string buffer.
965 exec_copyin_args(struct image_args *args, char *fname,
966 enum uio_seg segflg, char **argv, char **envv)
974 bzero(args, sizeof(*args));
978 * Allocate temporary demand zeroed space for argument and
979 * environment strings:
981 * o ARG_MAX for argument and environment;
982 * o MAXSHELLCMDLEN for the name of interpreters.
984 args->buf = (char *) kmem_alloc_wait(exec_map,
985 PATH_MAX + ARG_MAX + MAXSHELLCMDLEN);
986 if (args->buf == NULL)
988 args->begin_argv = args->buf;
989 args->endp = args->begin_argv;
990 args->stringspace = ARG_MAX;
992 args->fname = args->buf + ARG_MAX;
995 * Copy the file name.
997 error = (segflg == UIO_SYSSPACE) ?
998 copystr(fname, args->fname, PATH_MAX, &length) :
999 copyinstr(fname, args->fname, PATH_MAX, &length);
1004 * extract arguments first
1006 while ((argp = (caddr_t) (intptr_t) fuword(argv++))) {
1007 if (argp == (caddr_t) -1) {
1011 if ((error = copyinstr(argp, args->endp,
1012 args->stringspace, &length))) {
1013 if (error == ENAMETOOLONG)
1017 args->stringspace -= length;
1018 args->endp += length;
1022 args->begin_envv = args->endp;
1025 * extract environment strings
1028 while ((envp = (caddr_t)(intptr_t)fuword(envv++))) {
1029 if (envp == (caddr_t)-1) {
1033 if ((error = copyinstr(envp, args->endp,
1034 args->stringspace, &length))) {
1035 if (error == ENAMETOOLONG)
1039 args->stringspace -= length;
1040 args->endp += length;
1048 exec_free_args(args);
1053 exec_free_args(struct image_args *args)
1057 kmem_free_wakeup(exec_map, (vm_offset_t)args->buf,
1058 PATH_MAX + ARG_MAX + MAXSHELLCMDLEN);
1064 * Copy strings out to the new process address space, constructing
1065 * new arg and env vector tables. Return a pointer to the base
1066 * so that it can be used as the initial stack pointer.
1069 exec_copyout_strings(imgp)
1070 struct image_params *imgp;
1074 char *stringp, *destp;
1075 register_t *stack_base;
1076 struct ps_strings *arginfo;
1081 * Calculate string base and vector table pointers.
1082 * Also deal with signal trampoline code for this exec type.
1086 arginfo = (struct ps_strings *)p->p_sysent->sv_psstrings;
1087 if (p->p_sysent->sv_szsigcode != NULL)
1088 szsigcode = *(p->p_sysent->sv_szsigcode);
1089 destp = (caddr_t)arginfo - szsigcode - SPARE_USRSPACE -
1090 roundup((ARG_MAX - imgp->args->stringspace), sizeof(char *));
1096 copyout(p->p_sysent->sv_sigcode, ((caddr_t)arginfo -
1097 szsigcode), szsigcode);
1100 * If we have a valid auxargs ptr, prepare some room
1103 if (imgp->auxargs) {
1105 * 'AT_COUNT*2' is size for the ELF Auxargs data. This is for
1106 * lower compatibility.
1108 imgp->auxarg_size = (imgp->auxarg_size) ? imgp->auxarg_size :
1111 * The '+ 2' is for the null pointers at the end of each of
1112 * the arg and env vector sets,and imgp->auxarg_size is room
1113 * for argument of Runtime loader.
1115 vectp = (char **)(destp - (imgp->args->argc +
1116 imgp->args->envc + 2 + imgp->auxarg_size) *
1121 * The '+ 2' is for the null pointers at the end of each of
1122 * the arg and env vector sets
1124 vectp = (char **)(destp - (imgp->args->argc + imgp->args->envc + 2) *
1129 * vectp also becomes our initial stack base
1131 stack_base = (register_t *)vectp;
1133 stringp = imgp->args->begin_argv;
1134 argc = imgp->args->argc;
1135 envc = imgp->args->envc;
1138 * Copy out strings - arguments and environment.
1140 copyout(stringp, destp, ARG_MAX - imgp->args->stringspace);
1143 * Fill in "ps_strings" struct for ps, w, etc.
1145 suword(&arginfo->ps_argvstr, (long)(intptr_t)vectp);
1146 suword(&arginfo->ps_nargvstr, argc);
1149 * Fill in argument portion of vector table.
1151 for (; argc > 0; --argc) {
1152 suword(vectp++, (long)(intptr_t)destp);
1153 while (*stringp++ != 0)
1158 /* a null vector table pointer separates the argp's from the envp's */
1161 suword(&arginfo->ps_envstr, (long)(intptr_t)vectp);
1162 suword(&arginfo->ps_nenvstr, envc);
1165 * Fill in environment portion of vector table.
1167 for (; envc > 0; --envc) {
1168 suword(vectp++, (long)(intptr_t)destp);
1169 while (*stringp++ != 0)
1174 /* end of vector table is a null pointer */
1177 return (stack_base);
1181 * Check permissions of file to execute.
1182 * Called with imgp->vp locked.
1183 * Return 0 for success or error code on failure.
1186 exec_check_permissions(imgp)
1187 struct image_params *imgp;
1189 struct vnode *vp = imgp->vp;
1190 struct vattr *attr = imgp->attr;
1194 td = curthread; /* XXXKSE */
1196 /* Get file attributes */
1197 error = VOP_GETATTR(vp, attr, td->td_ucred, td);
1202 error = mac_check_vnode_exec(td->td_ucred, imgp->vp, imgp);
1208 * 1) Check if file execution is disabled for the filesystem that this
1210 * 2) Insure that at least one execute bit is on - otherwise root
1211 * will always succeed, and we don't want to happen unless the
1212 * file really is executable.
1213 * 3) Insure that the file is a regular file.
1215 if ((vp->v_mount->mnt_flag & MNT_NOEXEC) ||
1216 ((attr->va_mode & 0111) == 0) ||
1217 (attr->va_type != VREG))
1221 * Zero length files can't be exec'd
1223 if (attr->va_size == 0)
1227 * Check for execute permission to file based on current credentials.
1229 error = VOP_ACCESS(vp, VEXEC, td->td_ucred, td);
1234 * Check number of open-for-writes on the file and deny execution
1237 if (vp->v_writecount)
1241 * Call filesystem specific open routine (which does nothing in the
1244 error = VOP_OPEN(vp, FREAD, td->td_ucred, td, -1);
1249 * Exec handler registration
1252 exec_register(execsw_arg)
1253 const struct execsw *execsw_arg;
1255 const struct execsw **es, **xs, **newexecsw;
1256 int count = 2; /* New slot and trailing NULL */
1259 for (es = execsw; *es; es++)
1261 newexecsw = malloc(count * sizeof(*es), M_TEMP, M_WAITOK);
1262 if (newexecsw == NULL)
1266 for (es = execsw; *es; es++)
1271 free(execsw, M_TEMP);
1277 exec_unregister(execsw_arg)
1278 const struct execsw *execsw_arg;
1280 const struct execsw **es, **xs, **newexecsw;
1284 panic("unregister with no handlers left?\n");
1286 for (es = execsw; *es; es++) {
1287 if (*es == execsw_arg)
1292 for (es = execsw; *es; es++)
1293 if (*es != execsw_arg)
1295 newexecsw = malloc(count * sizeof(*es), M_TEMP, M_WAITOK);
1296 if (newexecsw == NULL)
1299 for (es = execsw; *es; es++)
1300 if (*es != execsw_arg)
1304 free(execsw, M_TEMP);