X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/a3d08fcd5120d2aa8303b6349ca8b14e3f284af3..cb3231590a3c94ab4375e2228bd5e86b0cf1ad7e:/bsd/kern/kern_exec.c?ds=sidebyside

diff --git a/bsd/kern/kern_exec.c b/bsd/kern/kern_exec.c
index 191e3f396..03bcf7896 100644
--- a/bsd/kern/kern_exec.c
+++ b/bsd/kern/kern_exec.c
@@ -1,23 +1,29 @@
 /*
- * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
- *
- * @APPLE_LICENSE_HEADER_START@
- * 
- * The contents of this file constitute Original Code as defined in and
- * are subject to the Apple Public Source License Version 1.1 (the
- * "License").  You may not use this file except in compliance with the
- * License.  Please obtain a copy of the License at
- * http://www.apple.com/publicsource and read it before using this file.
- * 
- * This Original Code and all software distributed under the License are
- * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * Copyright (c) 2000-2013 Apple Inc. All rights reserved.
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
+ *
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
+ *
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
- * License for the specific language governing rights and limitations
- * under the License.
- * 
- * @APPLE_LICENSE_HEADER_END@
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
 /* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
 /*
@@ -26,8 +32,6 @@
  * All rights reserved.  The CMU software License Agreement specifies
  * the terms and conditions for use and redistribution.
  */
- 
-#include <cputypes.h>
 
 /*-
  * Copyright (c) 1982, 1986, 1991, 1993
@@ -68,1302 +72,6415 @@
  *
  *	from: @(#)kern_exec.c	8.1 (Berkeley) 6/10/93
  */
+/*
+ * NOTICE: This file was modified by SPARTA, Inc. in 2005 to introduce
+ * support for mandatory and extensible security protections.  This notice
+ * is included in support of clause 2.2 (b) of the Apple Public License,
+ * Version 2.0.
+ */
 #include <machine/reg.h>
+#include <machine/cpu_capabilities.h>
 
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/filedesc.h>
 #include <sys/kernel.h>
-#include <sys/proc.h>
+#include <sys/proc_internal.h>
+#include <sys/kauth.h>
 #include <sys/user.h>
-#include <sys/buf.h>
 #include <sys/socketvar.h>
 #include <sys/malloc.h>
 #include <sys/namei.h>
-#include <sys/mount.h>
-#include <sys/vnode.h>		
-#include <sys/file.h>
+#include <sys/mount_internal.h>
+#include <sys/vnode_internal.h>
+#include <sys/file_internal.h>
 #include <sys/stat.h>
-#include <sys/uio.h>
+#include <sys/uio_internal.h>
 #include <sys/acct.h>
 #include <sys/exec.h>
 #include <sys/kdebug.h>
 #include <sys/signal.h>
 #include <sys/aio_kern.h>
+#include <sys/sysproto.h>
+#include <sys/persona.h>
+#include <sys/reason.h>
+#if SYSV_SHM
+#include <sys/shm_internal.h>           /* shmexec() */
+#endif
+#include <sys/ubc_internal.h>           /* ubc_map() */
+#include <sys/spawn.h>
+#include <sys/spawn_internal.h>
+#include <sys/process_policy.h>
+#include <sys/codesign.h>
+#include <sys/random.h>
+#include <crypto/sha1.h>
 
-#include <bsm/audit_kernel.h>
+#include <libkern/libkern.h>
 
+#include <security/audit/audit.h>
+
+#include <ipc/ipc_types.h>
+
+#include <mach/mach_param.h>
+#include <mach/mach_types.h>
+#include <mach/port.h>
+#include <mach/task.h>
+#include <mach/task_access.h>
+#include <mach/thread_act.h>
+#include <mach/vm_map.h>
+#include <mach/mach_vm.h>
 #include <mach/vm_param.h>
 
-#include <vm/vm_map.h>
+#include <kern/sched_prim.h> /* thread_wakeup() */
+#include <kern/affinity.h>
+#include <kern/assert.h>
+#include <kern/task.h>
+#include <kern/coalition.h>
+#include <kern/policy_internal.h>
+#include <kern/kalloc.h>
+
+#include <os/log.h>
+
+#if CONFIG_MACF
+#include <security/mac_framework.h>
+#include <security/mac_mach_internal.h>
+#endif
 
-extern vm_map_t vm_map_switch(vm_map_t    map); /* XXX */
+#if CONFIG_ARCADE
+#include <kern/arcade.h>
+#endif
 
+#include <vm/vm_map.h>
 #include <vm/vm_kern.h>
-#include <vm/vm_shared_memory_server.h>
+#include <vm/vm_protos.h>
+#include <vm/vm_kern.h>
+#include <vm/vm_fault.h>
+#include <vm/vm_pageout.h>
+
+#include <kdp/kdp_dyld.h>
+
+#include <machine/machine_routines.h>
+#include <machine/pal_routines.h>
+
+#include <pexpert/pexpert.h>
+
+#if CONFIG_MEMORYSTATUS
+#include <sys/kern_memorystatus.h>
+#endif
+
+#include <IOKit/IOBSD.h>
+
+extern boolean_t vm_darkwake_mode;
+
+extern int bootarg_execfailurereports; /* bsd_init.c */
+
+#if CONFIG_DTRACE
+/* Do not include dtrace.h, it redefines kmem_[alloc/free] */
+extern void dtrace_proc_exec(proc_t);
+extern void (*dtrace_proc_waitfor_exec_ptr)(proc_t);
+
+/*
+ * Since dtrace_proc_waitfor_exec_ptr can be added/removed in dtrace_subr.c,
+ * we will store its value before actually calling it.
+ */
+static void (*dtrace_proc_waitfor_hook)(proc_t) = NULL;
+
+#include <sys/dtrace_ptss.h>
+#endif
+
+/* support for child creation in exec after vfork */
+thread_t fork_create_child(task_t parent_task,
+    coalition_t *parent_coalition,
+    proc_t child_proc,
+    int inherit_memory,
+    int is_64bit_addr,
+    int is_64bit_data,
+    int in_exec);
+void vfork_exit(proc_t p, int rv);
+extern void proc_apply_task_networkbg_internal(proc_t, thread_t);
+extern void task_set_did_exec_flag(task_t task);
+extern void task_clear_exec_copy_flag(task_t task);
+proc_t proc_exec_switch_task(proc_t p, task_t old_task, task_t new_task, thread_t new_thread);
+boolean_t task_is_active(task_t);
+boolean_t thread_is_active(thread_t thread);
+void thread_copy_resource_info(thread_t dst_thread, thread_t src_thread);
+void *ipc_importance_exec_switch_task(task_t old_task, task_t new_task);
+extern void ipc_importance_release(void *elem);
+extern boolean_t task_has_watchports(task_t task);
+
+/*
+ * Mach things for which prototypes are unavailable from Mach headers
+ */
+#define IPC_KMSG_FLAGS_ALLOW_IMMOVABLE_SEND 0x1
+void            ipc_task_reset(
+	task_t          task);
+void            ipc_thread_reset(
+	thread_t        thread);
+kern_return_t ipc_object_copyin(
+	ipc_space_t             space,
+	mach_port_name_t        name,
+	mach_msg_type_name_t    msgt_name,
+	ipc_object_t            *objectp,
+	mach_port_context_t     context,
+	mach_msg_guard_flags_t  *guard_flags,
+	uint32_t                kmsg_flags);
+void ipc_port_release_send(ipc_port_t);
+
+#if DEVELOPMENT || DEBUG
+void task_importance_update_owner_info(task_t);
+#endif
+
+extern struct savearea *get_user_regs(thread_t);
+
+__attribute__((noinline)) int __EXEC_WAITING_ON_TASKGATED_CODE_SIGNATURE_UPCALL__(mach_port_t task_access_port, int32_t new_pid);
 
 #include <kern/thread.h>
 #include <kern/task.h>
-
 #include <kern/ast.h>
 #include <kern/mach_loader.h>
+#include <kern/mach_fat.h>
 #include <mach-o/fat.h>
 #include <mach-o/loader.h>
 #include <machine/vmparam.h>
-#if KTRACE   
-#include <sys/ktrace.h>
-#include <sys/ubc.h>
-#endif
+#include <sys/imgact.h>
+
+#include <sys/sdt.h>
+
 
-int	app_profile = 0;
+/*
+ * EAI_ITERLIMIT	The maximum number of times to iterate an image
+ *			activator in exec_activate_image() before treating
+ *			it as malformed/corrupt.
+ */
+#define EAI_ITERLIMIT           3
+
+/*
+ * For #! interpreter parsing
+ */
+#define IS_WHITESPACE(ch) ((ch == ' ') || (ch == '\t'))
+#define IS_EOL(ch) ((ch == '#') || (ch == '\n'))
 
 extern vm_map_t bsd_pageable_map;
+extern const struct fileops vnops;
+extern int nextpidversion;
+
+#define USER_ADDR_ALIGN(addr, val) \
+	( ( (user_addr_t)(addr) + (val) - 1) \
+	        & ~((val) - 1) )
+
+/* Platform Code Exec Logging */
+static int platform_exec_logging = 0;
+
+SYSCTL_DECL(_security_mac);
 
-#define	ROUND_PTR(type, addr)	\
-	(type *)( ( (unsigned)(addr) + 16 - 1) \
-		  & ~(16 - 1) )
+SYSCTL_INT(_security_mac, OID_AUTO, platform_exec_logging, CTLFLAG_RW, &platform_exec_logging, 0,
+    "log cdhashes for all platform binary executions");
 
+static os_log_t peLog = OS_LOG_DEFAULT;
+
+struct exec_port_actions {
+	uint32_t portwatch_count;
+	uint32_t registered_count;
+	ipc_port_t *portwatch_array;
+	ipc_port_t *registered_array;
+};
+
+struct image_params;    /* Forward */
+static int exec_activate_image(struct image_params *imgp);
+static int exec_copyout_strings(struct image_params *imgp, user_addr_t *stackp);
 static int load_return_to_errno(load_return_t lrtn);
-int execve(struct proc *p, struct execve_args *uap, register_t *retval);
-static int execargs_alloc(vm_offset_t *addrp);
-static int execargs_free(vm_offset_t addr);
+static int execargs_alloc(struct image_params *imgp);
+static int execargs_free(struct image_params *imgp);
+static int exec_check_permissions(struct image_params *imgp);
+static int exec_extract_strings(struct image_params *imgp);
+static int exec_add_apple_strings(struct image_params *imgp, const load_result_t *load_result);
+static int exec_handle_sugid(struct image_params *imgp);
 static int sugid_scripts = 0;
-SYSCTL_INT (_kern, OID_AUTO, sugid_scripts, CTLFLAG_RW, &sugid_scripts, 0, "");
+SYSCTL_INT(_kern, OID_AUTO, sugid_scripts, CTLFLAG_RW | CTLFLAG_LOCKED, &sugid_scripts, 0, "");
+static kern_return_t create_unix_stack(vm_map_t map, load_result_t* load_result, proc_t p);
+static int copyoutptr(user_addr_t ua, user_addr_t ptr, int ptr_size);
+static void exec_resettextvp(proc_t, struct image_params *);
+static int check_for_signature(proc_t, struct image_params *);
+static void exec_prefault_data(proc_t, struct image_params *, load_result_t *);
+static errno_t exec_handle_port_actions(struct image_params *imgp,
+    struct exec_port_actions *port_actions);
+static errno_t exec_handle_spawnattr_policy(proc_t p, thread_t thread, int psa_apptype, uint64_t psa_qos_clamp,
+    uint64_t psa_darwin_role, struct exec_port_actions *port_actions);
+static void exec_port_actions_destroy(struct exec_port_actions *port_actions);
 
-int
-execv(p, args, retval)
-	struct proc *p;
-	void *args;
-	int *retval;
+/*
+ * exec_add_user_string
+ *
+ * Add the requested string to the string space area.
+ *
+ * Parameters;	struct image_params *		image parameter block
+ *		user_addr_t			string to add to strings area
+ *		int				segment from which string comes
+ *		boolean_t			TRUE if string contributes to NCARGS
+ *
+ * Returns:	0			Success
+ *		!0			Failure errno from copyinstr()
+ *
+ * Implicit returns:
+ *		(imgp->ip_strendp)	updated location of next add, if any
+ *		(imgp->ip_strspace)	updated byte count of space remaining
+ *		(imgp->ip_argspace) updated byte count of space in NCARGS
+ */
+static int
+exec_add_user_string(struct image_params *imgp, user_addr_t str, int seg, boolean_t is_ncargs)
 {
-	((struct execve_args *)args)->envp = NULL;
-	return (execve(p, args, retval));
-}
+	int error = 0;
 
-extern char classichandler[32];
-extern long classichandler_fsid;
-extern long classichandler_fileid;
+	do {
+		size_t len = 0;
+		int space;
 
-/*
- * Helper routine to get rid of a loop in execve.  Given a pointer to
- * something for the arg list (which might be in kernel space or in user
- * space), copy it into the kernel buffer at the currentWritePt.  This code
- * does the proper thing to get the data transferred.
- * bytesWritten, currentWritePt, and bytesLeft are kept up-to-date.
- */
+		if (is_ncargs) {
+			space = imgp->ip_argspace; /* by definition smaller than ip_strspace */
+		} else {
+			space = imgp->ip_strspace;
+		}
 
-static int copyArgument(char *argument, int pointerInKernel,
-			int *bytesWritten,char **currentWritePt,
-			int *bytesLeft){
-        int error = 0;
-        do {
-                size_t len = 0;
-		if (*bytesLeft <= 0) {
+		if (space <= 0) {
 			error = E2BIG;
 			break;
 		}
-		if (pointerInKernel == UIO_SYSSPACE) {
-			error = copystr(argument, *currentWritePt, (unsigned)*bytesLeft, &len);
-		} else  {
-	       /*
-	        * pointer in kernel == UIO_USERSPACE
-	        * Copy in from user space.
-	        */ 
-		  error = copyinstr((caddr_t)argument, *currentWritePt, (unsigned)*bytesLeft,
-			    &len);
-		}
-		*currentWritePt += len;
-		*bytesWritten += len;
-		*bytesLeft -= len;
+
+		if (!UIO_SEG_IS_USER_SPACE(seg)) {
+			char *kstr = CAST_DOWN(char *, str);     /* SAFE */
+			error = copystr(kstr, imgp->ip_strendp, space, &len);
+		} else {
+			error = copyinstr(str, imgp->ip_strendp, space, &len);
+		}
+
+		imgp->ip_strendp += len;
+		imgp->ip_strspace -= len;
+		if (is_ncargs) {
+			imgp->ip_argspace -= len;
+		}
 	} while (error == ENAMETOOLONG);
+
 	return error;
 }
 
-/* ARGSUSED */
-int
-execve(p, uap, retval)
-	register struct proc *p;
-	register struct execve_args *uap;
-	register_t *retval;
+/*
+ * dyld is now passed the executable path as a getenv-like variable
+ * in the same fashion as the stack_guard and malloc_entropy keys.
+ */
+#define EXECUTABLE_KEY "executable_path="
+
+/*
+ * exec_save_path
+ *
+ * To support new app package launching for Mac OS X, the dyld needs the
+ * first argument to execve() stored on the user stack.
+ *
+ * Save the executable path name at the bottom of the strings area and set
+ * the argument vector pointer to the location following that to indicate
+ * the start of the argument and environment tuples, setting the remaining
+ * string space count to the size of the string area minus the path length.
+ *
+ * Parameters;	struct image_params *		image parameter block
+ *		char *				path used to invoke program
+ *		int				segment from which path comes
+ *
+ * Returns:	int			0	Success
+ *		EFAULT				Bad address
+ *	copy[in]str:EFAULT			Bad address
+ *	copy[in]str:ENAMETOOLONG		Filename too long
+ *
+ * Implicit returns:
+ *		(imgp->ip_strings)		saved path
+ *		(imgp->ip_strspace)		space remaining in ip_strings
+ *		(imgp->ip_strendp)		start of remaining copy area
+ *		(imgp->ip_argspace)		space remaining of NCARGS
+ *		(imgp->ip_applec)		Initial applev[0]
+ *
+ * Note:	We have to do this before the initial namei() since in the
+ *		path contains symbolic links, namei() will overwrite the
+ *		original path buffer contents.  If the last symbolic link
+ *		resolved was a relative pathname, we would lose the original
+ *		"path", which could be an absolute pathname. This might be
+ *		unacceptable for dyld.
+ */
+static int
+exec_save_path(struct image_params *imgp, user_addr_t path, int seg, const char **excpath)
 {
-	register struct ucred *cred = p->p_ucred;
-	register struct filedesc *fdp = p->p_fd;
-	int nc;
-	char *cp;
-	int na, ne, ucp, ap, cc;
-	unsigned len;
-	int executingInterpreter=0;
-
-	int executingClassic=0;
-	char binaryWithClassicName[sizeof(p->p_comm)] = {0};
-	char *execnamep;
-	struct vnode *vp;
-	struct vattr vattr;
-	struct vattr origvattr;
-	vm_offset_t execargs;
-	struct nameidata nd;
-	struct ps_strings ps;
-#define	SHSIZE	512
-	/* Argument(s) to an interpreter.  If we're executing a shell
-	 * script, the name (#!/bin/csh) is allowed to be followed by
-	 * arguments.  cfarg holds these arguments.
-	 */
-	char cfarg[SHSIZE];
-	boolean_t		is_fat;
-	kern_return_t		ret;
-	struct mach_header	*mach_header;
-	struct fat_header	*fat_header;
-	struct fat_arch		fat_arch;
-	load_return_t		lret;
-	load_result_t		load_result;
-	struct uthread		*uthread;
-	vm_map_t old_map;
-	vm_map_t map;
-	int i;
-	boolean_t				clean_regions = FALSE;
-	shared_region_mapping_t shared_region = NULL;
-    shared_region_mapping_t initial_region = NULL;
-
-	union {
-		/* #! and name of interpreter */
-		char			ex_shell[SHSIZE];
-		/* Mach-O executable */
-		struct mach_header	mach_header;
-		/* Fat executable */
-		struct fat_header	fat_header;
-		char	pad[512];
-	} exdata;
-	int resid, error;
-	char *savedpath;
-	int savedpathlen = 0;
-	vm_offset_t *execargsp;
-	char *cpnospace;
-	task_t  task;
-	task_t new_task;
-	thread_act_t thr_act;
-	int numthreads;
-	int vfexec=0;
-	unsigned long arch_offset =0;
-	unsigned long arch_size = 0;
-        char		*ws_cache_name = NULL;	/* used for pre-heat */
-
-        /*
-         * XXXAUDIT: Currently, we only audit the pathname of the binary.
-         * There may also be poor interaction with dyld.
-         */
-
-	cfarg[0] = '\0'; /* initialize to null value. */
-	task = current_task();
-	thr_act = current_act();
-	uthread = get_bsdthread_info(thr_act);
+	int error;
+	size_t len;
+	char *kpath;
+
+	// imgp->ip_strings can come out of a cache, so we need to obliterate the
+	// old path.
+	memset(imgp->ip_strings, '\0', strlen(EXECUTABLE_KEY) + MAXPATHLEN);
+
+	len = MIN(MAXPATHLEN, imgp->ip_strspace);
+
+	switch (seg) {
+	case UIO_USERSPACE32:
+	case UIO_USERSPACE64:   /* Same for copyin()... */
+		error = copyinstr(path, imgp->ip_strings + strlen(EXECUTABLE_KEY), len, &len);
+		break;
+	case UIO_SYSSPACE:
+		kpath = CAST_DOWN(char *, path); /* SAFE */
+		error = copystr(kpath, imgp->ip_strings + strlen(EXECUTABLE_KEY), len, &len);
+		break;
+	default:
+		error = EFAULT;
+		break;
+	}
 
-	if (uthread->uu_flag & P_VFORK) {
-			vfexec = 1; /* Mark in exec */
-	} else {
-		if (task != kernel_task) { 
-			numthreads = get_task_numacts(task);
-			if (numthreads <= 0 )
-				return(EINVAL);
-			if (numthreads > 1) {
-				return(EOPNOTSUPP);
-			}
+	if (!error) {
+		bcopy(EXECUTABLE_KEY, imgp->ip_strings, strlen(EXECUTABLE_KEY));
+		len += strlen(EXECUTABLE_KEY);
+
+		imgp->ip_strendp += len;
+		imgp->ip_strspace -= len;
+
+		if (excpath) {
+			*excpath = imgp->ip_strings + strlen(EXECUTABLE_KEY);
 		}
 	}
 
-	error = execargs_alloc(&execargs);
-	if (error)
-		return(error);
+	return error;
+}
 
-	savedpath = (char *)execargs;
+/*
+ * exec_reset_save_path
+ *
+ * If we detect a shell script, we need to reset the string area
+ * state so that the interpreter can be saved onto the stack.
+ *
+ * Parameters;	struct image_params *		image parameter block
+ *
+ * Returns:	int			0	Success
+ *
+ * Implicit returns:
+ *		(imgp->ip_strings)		saved path
+ *		(imgp->ip_strspace)		space remaining in ip_strings
+ *		(imgp->ip_strendp)		start of remaining copy area
+ *		(imgp->ip_argspace)		space remaining of NCARGS
+ *
+ */
+static int
+exec_reset_save_path(struct image_params *imgp)
+{
+	imgp->ip_strendp = imgp->ip_strings;
+	imgp->ip_argspace = NCARGS;
+	imgp->ip_strspace = (NCARGS + PAGE_SIZE);
 
-	/*
-	 * To support new app package launching for Mac OS X, the dyld
-	 * needs the first argument to execve() stored on the user stack.
-	 * Copyin the "path" at the begining of the "execargs" buffer
-	 * allocated above.
-	 *
-	 * We have to do this before namei() because in case of
-	 * symbolic links, namei() would overwrite the original "path".
-	 * In case the last symbolic link resolved was a relative pathname
-	 * we would lose the original "path", which could be an
-	 * absolute pathname. This might be unacceptable for dyld.
-	 */
-	/* XXX We could optimize to avoid copyinstr in the namei() */
+	return 0;
+}
+
+/*
+ * exec_shell_imgact
+ *
+ * Image activator for interpreter scripts.  If the image begins with
+ * the characters "#!", then it is an interpreter script.  Verify the
+ * length of the script line indicating the interpreter is not in
+ * excess of the maximum allowed size.  If this is the case, then
+ * break out the arguments, if any, which are separated by white
+ * space, and copy them into the argument save area as if they were
+ * provided on the command line before all other arguments.  The line
+ * ends when we encounter a comment character ('#') or newline.
+ *
+ * Parameters;	struct image_params *	image parameter block
+ *
+ * Returns:	-1			not an interpreter (keep looking)
+ *		-3			Success: interpreter: relookup
+ *		>0			Failure: interpreter: error number
+ *
+ * A return value other than -1 indicates subsequent image activators should
+ * not be given the opportunity to attempt to activate the image.
+ */
+static int
+exec_shell_imgact(struct image_params *imgp)
+{
+	char *vdata = imgp->ip_vdata;
+	char *ihp;
+	char *line_startp, *line_endp;
+	char *interp;
 
 	/*
-	 * XXXAUDIT: Note: the double copyin introduces an audit
-	 * race.  To correct this race, we must use a single
-	 * copyin().
+	 * Make sure it's a shell script.  If we've already redirected
+	 * from an interpreted file once, don't do it again.
 	 */
-	
-	error = copyinstr(uap->fname, savedpath,
-				MAXPATHLEN, (size_t *)&savedpathlen);
-	if (error) {
-		execargs_free(execargs);
-		return(error);
-	}
-	/*
-	 * copyinstr will put in savedpathlen, the count of
-	 * characters (including NULL) in the path.
-	 * No app profiles under chroot
-	 */
-
-	if((fdp->fd_rdir == NULLVP) && (app_profile != 0)) {
-
-		/* grab the name of the file out of its path */
-		/* we will need this for lookup within the   */
-		/* name file */
-		ws_cache_name = savedpath + savedpathlen;
-               	while (ws_cache_name[0] != '/') {
-               		if(ws_cache_name == savedpath) {
-               	        	ws_cache_name--;
-               	         	break;
-                      	}
-               		ws_cache_name--;
-               	}
-               	ws_cache_name++;
-	}
-
-	/* Save the name aside for future use */
-	execargsp = (vm_offset_t *)((char *)(execargs) + savedpathlen);
-	
-	NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | SAVENAME | AUDITVNPATH1,
-					UIO_USERSPACE, uap->fname, p);
-	error = namei(&nd);
-	if (error)
-		goto bad1;
-	vp = nd.ni_vp;
-	VOP_LEASE(vp, p, p->p_ucred, LEASE_READ);
-
-	if ((error = VOP_GETATTR(vp, &origvattr, p->p_ucred, p)))
-		goto bad;
-
-	/* Check mount point */
-	if (vp->v_mount->mnt_flag & MNT_NOEXEC) {
-		error = EACCES;
-		goto bad;
+	if (vdata[0] != '#' ||
+	    vdata[1] != '!' ||
+	    (imgp->ip_flags & IMGPF_INTERPRET) != 0) {
+		return -1;
 	}
 
-	if ((vp->v_mount->mnt_flag & MNT_NOSUID) || (p->p_flag & P_TRACED))
-		origvattr.va_mode &= ~(VSUID | VSGID);
-		
-	*(&vattr) = *(&origvattr);
+	if (imgp->ip_origcputype != 0) {
+		/* Fat header previously matched, don't allow shell script inside */
+		return -1;
+	}
 
-again:
-	error = check_exec_access(p, vp, &vattr);
-	if (error)
-		goto bad;
+	imgp->ip_flags |= IMGPF_INTERPRET;
+	imgp->ip_interp_sugid_fd = -1;
+	imgp->ip_interp_buffer[0] = '\0';
 
-	/*
-	 * Read in first few bytes of file for segment sizes, magic number:
-	 *	407 = plain executable
-	 *	410 = RO text
-	 *	413 = demand paged RO text
-	 * Also an ASCII line beginning with #! is
-	 * the file name of a ``shell'' and arguments may be prepended
-	 * to the argument list if given here.
-	 *
-	 * SHELL NAMES ARE LIMITED IN LENGTH.
-	 *
-	 * ONLY ONE ARGUMENT MAY BE PASSED TO THE SHELL FROM
-	 * THE ASCII LINE.
+	/* Check to see if SUGID scripts are permitted.  If they aren't then
+	 * clear the SUGID bits.
+	 * imgp->ip_vattr is known to be valid.
 	 */
+	if (sugid_scripts == 0) {
+		imgp->ip_origvattr->va_mode &= ~(VSUID | VSGID);
+	}
 
-	exdata.ex_shell[0] = '\0';	/* for zero length files */
-
-	error = vn_rdwr(UIO_READ, vp, (caddr_t)&exdata, sizeof (exdata), 0,
-			UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid, p);
-
-	if (error)
-		goto bad;
+	/* Try to find the first non-whitespace character */
+	for (ihp = &vdata[2]; ihp < &vdata[IMG_SHSIZE]; ihp++) {
+		if (IS_EOL(*ihp)) {
+			/* Did not find interpreter, "#!\n" */
+			return ENOEXEC;
+		} else if (IS_WHITESPACE(*ihp)) {
+			/* Whitespace, like "#!    /bin/sh\n", keep going. */
+		} else {
+			/* Found start of interpreter */
+			break;
+		}
+	}
 
-#ifndef lint
-	if (resid > sizeof(exdata) - min(sizeof(exdata.mach_header),
-					 sizeof(exdata.fat_header))
-	    && exdata.ex_shell[0] != '#') {
-		error = ENOEXEC;
-		goto bad;
+	if (ihp == &vdata[IMG_SHSIZE]) {
+		/* All whitespace, like "#!           " */
+		return ENOEXEC;
 	}
-#endif /* lint */
-	mach_header = &exdata.mach_header;
-	fat_header = &exdata.fat_header;
-	if ((mach_header->magic == MH_CIGAM) &&
-	    (classichandler[0] == 0)) {
-		error = EBADARCH;
-		goto bad;
-	} else if ((mach_header->magic == MH_MAGIC) || 
-               (mach_header->magic == MH_CIGAM)) {
-	    is_fat = FALSE;
-	} else if ((fat_header->magic == FAT_MAGIC) ||
-		       (fat_header->magic == FAT_CIGAM)) {
-	    is_fat = TRUE;
-	} else {
-	  /* If we've already redirected once from an interpreted file
-	   * to an interpreter, don't permit the second time.
-	   */
-		if (exdata.ex_shell[0] != '#' ||
-		    exdata.ex_shell[1] != '!' ||
-		    executingInterpreter) {
-			error = ENOEXEC;
-			goto bad;
-		}
-		if (executingClassic == 1) {
-		  error = EBADARCH;
-		  goto bad;
-		}
 
-		/* Check to see if SUGID scripts are permitted.  If they aren't then
-		 * clear the SUGID bits.
-		 */
-	        if (sugid_scripts == 0) {
-		   origvattr.va_mode &= ~(VSUID | VSGID);
-        	}
-
-		cp = &exdata.ex_shell[2];		/* skip "#!" */
-		while (cp < &exdata.ex_shell[SHSIZE]) {
-			if (*cp == '\t')		/* convert all tabs to spaces */
-				*cp = ' ';
-			else if (*cp == '\n' || *cp == '#') {
-				*cp = '\0';			/* trunc the line at nl or comment */
-
- 				/* go back and remove the spaces before the /n or # */
- 				/* todo: do we have to do this if we fix the passing of args to shells ? */
-				if ( cp != &exdata.ex_shell[2] ) {
-					do {
-						if ( *(cp-1) != ' ')
-							break;
-						*(--cp) = '\0';
-					} while ( cp != &exdata.ex_shell[2] );
-				}
-				break;
-			}
-			cp++;
-		}
-		if (*cp != '\0') {
-			error = ENOEXEC;
-			goto bad;
-		}
-		cp = &exdata.ex_shell[2];
-		while (*cp == ' ')
-			cp++;
-		execnamep = cp;
-		while (*cp && *cp != ' ')
-			cp++;
-		cfarg[0] = '\0';
-		cpnospace = cp;
-		if (*cp) {
-			*cp++ = '\0';
-			while (*cp == ' ')
-				cp++;
-			if (*cp)
-				bcopy((caddr_t)cp, (caddr_t)cfarg, SHSIZE);
+	line_startp = ihp;
+
+	/* Try to find the end of the interpreter+args string */
+	for (; ihp < &vdata[IMG_SHSIZE]; ihp++) {
+		if (IS_EOL(*ihp)) {
+			/* Got it */
+			break;
+		} else {
+			/* Still part of interpreter or args */
 		}
+	}
 
-		/*
-		 * Support for new app package launching for Mac OS X.
-		 * We are about to retry the execve() by changing the path to the
-		 * interpreter name. Need to re-initialize the savedpath and
-		 * savedpathlen. +1 for NULL.
-		 */
-		savedpathlen = (cpnospace - execnamep + 1);
-		error = copystr(execnamep, savedpath,
-					savedpathlen, (size_t *)&savedpathlen);
-		if (error)
-			goto bad;
+	if (ihp == &vdata[IMG_SHSIZE]) {
+		/* A long line, like "#! blah blah blah" without end */
+		return ENOEXEC;
+	}
 
-		/* Save the name aside for future use */
-		execargsp = (vm_offset_t *)((char *)(execargs) + savedpathlen);
-
-		executingInterpreter= 1;
-		vput(vp);
-		nd.ni_cnd.cn_nameiop = LOOKUP;
-		nd.ni_cnd.cn_flags = (nd.ni_cnd.cn_flags & HASBUF) |
-						(FOLLOW | LOCKLEAF | SAVENAME);
-		nd.ni_segflg = UIO_SYSSPACE;
-		nd.ni_dirp = execnamep;
-		if ((error = namei(&nd)))
-			goto bad1;
-		vp = nd.ni_vp;
-		VOP_LEASE(vp, p, cred, LEASE_READ);
-		if ((error = VOP_GETATTR(vp, &vattr, p->p_ucred, p)))
-			goto bad;
-		goto again;
+	/* Backtrack until we find the last non-whitespace */
+	while (IS_EOL(*ihp) || IS_WHITESPACE(*ihp)) {
+		ihp--;
 	}
 
+	/* The character after the last non-whitespace is our logical end of line */
+	line_endp = ihp + 1;
+
 	/*
-	 * Collect arguments on "file" in swap space.
-	 */
-	na = 0;
-	ne = 0;
-	nc = 0;
-	cc = 0;
-	/*
-	 * Support for new app package launching for Mac OS X allocates
-	 * the "path" at the begining.
-	 * execargs get allocated after that
-	 */
-	cp = (char *) execargsp;	/* running pointer for copy */
-	/*
-	 * size of execargs less sizeof "path",
-	 * a pointer to "path" and a NULL poiter
-	 */
-	cc = NCARGS - savedpathlen - 2*NBPW;
-	/*
-	 * Copy arguments into file in argdev area.
+	 * Now we have pointers to the usable part of:
+	 *
+	 * "#!  /usr/bin/int first    second   third    \n"
+	 *      ^ line_startp                       ^ line_endp
 	 */
 
+	/* copy the interpreter name */
+	interp = imgp->ip_interp_buffer;
+	for (ihp = line_startp; (ihp < line_endp) && !IS_WHITESPACE(*ihp); ihp++) {
+		*interp++ = *ihp;
+	}
+	*interp = '\0';
+
+	exec_reset_save_path(imgp);
+	exec_save_path(imgp, CAST_USER_ADDR_T(imgp->ip_interp_buffer),
+	    UIO_SYSSPACE, NULL);
+
+	/* Copy the entire interpreter + args for later processing into argv[] */
+	interp = imgp->ip_interp_buffer;
+	for (ihp = line_startp; (ihp < line_endp); ihp++) {
+		*interp++ = *ihp;
+	}
+	*interp = '\0';
 
+#if !SECURE_KERNEL
 	/*
-	 * If we have a fat file, find "our" executable.
+	 * If we have an SUID or SGID script, create a file descriptor
+	 * from the vnode and pass /dev/fd/%d instead of the actual
+	 * path name so that the script does not get opened twice
 	 */
-	if (is_fat) {
-		/*
-		 * Look up our architecture in the fat file.
-		 */
-		lret = fatfile_getarch_affinity(vp,(vm_offset_t)fat_header, &fat_arch,
-						(p->p_flag & P_AFFINITY));
-		if (lret != LOAD_SUCCESS) {
-			error = load_return_to_errno(lret);
-			goto bad;
-		}
-		/* Read the Mach-O header out of it */
-		error = vn_rdwr(UIO_READ, vp, (caddr_t)&exdata.mach_header,
-				sizeof (exdata.mach_header),
-				fat_arch.offset,
-				UIO_SYSSPACE, (IO_UNIT|IO_NODELOCKED), cred, &resid, p);
-
+	if (imgp->ip_origvattr->va_mode & (VSUID | VSGID)) {
+		proc_t p;
+		struct fileproc *fp;
+		int fd;
+		int error;
+
+		p = vfs_context_proc(imgp->ip_vfs_context);
+		error = falloc(p, &fp, &fd, imgp->ip_vfs_context);
 		if (error) {
-			goto bad;
+			return error;
 		}
 
-		/* Did we read a complete header? */
-		if (resid) {
-			error = EBADEXEC;
-			goto bad;
-		}
+		fp->f_fglob->fg_flag = FREAD;
+		fp->f_fglob->fg_ops = &vnops;
+		fp->f_fglob->fg_data = (caddr_t)imgp->ip_vp;
 
-		/* Is what we found a Mach-O executable */
-		if ((mach_header->magic != MH_MAGIC) &&
-		    (mach_header->magic != MH_CIGAM)) {
-			error = ENOEXEC;
-			goto bad;
-		}
+		proc_fdlock(p);
+		procfdtbl_releasefd(p, fd, NULL);
+		fp_drop(p, fd, fp, 1);
+		proc_fdunlock(p);
+		vnode_ref(imgp->ip_vp);
 
-		arch_offset = fat_arch.offset;
-		arch_size = fat_arch.size;
-	} else {
-		/*
-		 *	Load the Mach-O file.
-		 */
-		arch_offset = 0;
-		arch_size = (u_long)vattr.va_size;
+		imgp->ip_interp_sugid_fd = fd;
 	}
+#endif
 
-	if ( ! check_cpu_subtype(mach_header->cpusubtype) ) {
-		error = EBADARCH;
+	return -3;
+}
+
+
+
+/*
+ * exec_fat_imgact
+ *
+ * Image activator for fat 1.0 binaries.  If the binary is fat, then we
+ * need to select an image from it internally, and make that the image
+ * we are going to attempt to execute.  At present, this consists of
+ * reloading the first page for the image with a first page from the
+ * offset location indicated by the fat header.
+ *
+ * Parameters;	struct image_params *	image parameter block
+ *
+ * Returns:	-1			not a fat binary (keep looking)
+ *		-2			Success: encapsulated binary: reread
+ *		>0			Failure: error number
+ *
+ * Important:	This image activator is byte order neutral.
+ *
+ * Note:	A return value other than -1 indicates subsequent image
+ *		activators should not be given the opportunity to attempt
+ *		to activate the image.
+ *
+ *              If we find an encapsulated binary, we make no assertions
+ *		about its  validity; instead, we leave that up to a rescan
+ *		for an activator to claim it, and, if it is claimed by one,
+ *		that activator is responsible for determining validity.
+ */
+static int
+exec_fat_imgact(struct image_params *imgp)
+{
+	proc_t p = vfs_context_proc(imgp->ip_vfs_context);
+	kauth_cred_t cred = kauth_cred_proc_ref(p);
+	struct fat_header *fat_header = (struct fat_header *)imgp->ip_vdata;
+	struct _posix_spawnattr *psa = NULL;
+	struct fat_arch fat_arch;
+	int resid, error;
+	load_return_t lret;
+
+	if (imgp->ip_origcputype != 0) {
+		/* Fat header previously matched, don't allow another fat file inside */
+		error = -1; /* not claimed */
 		goto bad;
 	}
 
-	if (mach_header->magic == MH_CIGAM) {
-
-		int classicBinaryLen = nd.ni_cnd.cn_namelen;
-		if (classicBinaryLen > MAXCOMLEN)
-	    	classicBinaryLen = MAXCOMLEN;
-		bcopy((caddr_t)nd.ni_cnd.cn_nameptr,
-				(caddr_t)binaryWithClassicName, 
-				(unsigned)classicBinaryLen);
-		binaryWithClassicName[classicBinaryLen] = '\0';
-		executingClassic = 1;
+	/* Make sure it's a fat binary */
+	if (OSSwapBigToHostInt32(fat_header->magic) != FAT_MAGIC) {
+		error = -1; /* not claimed */
+		goto bad;
+	}
 
-		vput(vp); /* cleanup? */
-		nd.ni_cnd.cn_nameiop = LOOKUP;
+	/* imgp->ip_vdata has PAGE_SIZE, zerofilled if the file is smaller */
+	lret = fatfile_validate_fatarches((vm_offset_t)fat_header, PAGE_SIZE);
+	if (lret != LOAD_SUCCESS) {
+		error = load_return_to_errno(lret);
+		goto bad;
+	}
 
-		nd.ni_cnd.cn_flags = (nd.ni_cnd.cn_flags & HASBUF) |
-		/*      (FOLLOW | LOCKLEAF | SAVENAME) */
-            	(LOCKLEAF | SAVENAME);
-	         nd.ni_segflg = UIO_SYSSPACE;
+	/* If posix_spawn binprefs exist, respect those prefs. */
+	psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
+	if (psa != NULL && psa->psa_binprefs[0] != 0) {
+		uint32_t pr = 0;
+
+		/* Check each preference listed against all arches in header */
+		for (pr = 0; pr < NBINPREFS; pr++) {
+			cpu_type_t pref = psa->psa_binprefs[pr];
+			if (pref == 0) {
+				/* No suitable arch in the pref list */
+				error = EBADARCH;
+				goto bad;
+			}
 
-       		nd.ni_dirp = classichandler;
-       		if ((error = namei(&nd)) != 0) {
-			error = EBADARCH;
-       			goto bad1;
-         	}
-		vp = nd.ni_vp;
+			if (pref == CPU_TYPE_ANY) {
+				/* Fall through to regular grading */
+				goto regular_grading;
+			}
 
-		VOP_LEASE(vp,p,cred,LEASE_READ);
-		if ((error = VOP_GETATTR(vp,&vattr,p->p_ucred,p))) {
-			goto bad;
+			lret = fatfile_getbestarch_for_cputype(pref,
+			    (vm_offset_t)fat_header,
+			    PAGE_SIZE,
+			    imgp,
+			    &fat_arch);
+			if (lret == LOAD_SUCCESS) {
+				goto use_arch;
+			}
 		}
-		goto again;
-	}
-
-	if (uap->argp != NULL) {
-	  /* geez -- why would argp ever be NULL, and why would we proceed? */
-	  
-	  /* First, handle any argument massaging */
-	  if (executingInterpreter && executingClassic) {
-	    error = copyArgument(classichandler,UIO_SYSSPACE,&nc,&cp,&cc);
-	    na++;
-	    if (error) goto bad;
-	    
-	    /* Now name the interpreter. */
-	    error = copyArgument(savedpath,UIO_SYSSPACE,&nc,&cp,&cc);
-	    na++;
-	    if (error) goto bad;
-
-	    /*
-	     * if we're running an interpreter, as we'd be passing the
-	     * command line executable as an argument to the interpreter already.
-	     * Doing "execve("myShellScript","bogusName",arg1,arg2,...)
-	     * probably shouldn't ever let bogusName be seen by the shell
-	     * script.
-	     */
-
-	    if (cfarg[0]) {
-	      error = copyArgument(cfarg,UIO_SYSSPACE,&nc,&cp,&cc);
-	      na++;
-	      if (error) goto bad;
-	    }
-
-	    char* originalExecutable = uap->fname;
-	    error = copyArgument(originalExecutable,UIO_USERSPACE,&nc,&cp,&cc);
-	    na++;
-	    /* remove argv[0] b/c we've already placed it at */
-	    /* this point */
-	    uap->argp++;
-	    if (error) goto bad;
-
-	    /* and continue with rest of the arguments. */
-	  } else if (executingClassic) {
-	    error = copyArgument(classichandler,UIO_SYSSPACE,&nc,&cp,&cc);
-	    na++;
-	    if (error) goto bad;
-	    
-	    char* originalExecutable = uap->fname;
-	    error = copyArgument(originalExecutable,UIO_USERSPACE,&nc,&cp,&cc);
-	    if (error) goto bad;
-	    uap->argp++;
-	    na++;
-
-	    /* and rest of arguments continue as before. */
-	  } else if (executingInterpreter) {
-	    char *actualExecutable = nd.ni_cnd.cn_nameptr;
-	    error = copyArgument(actualExecutable,UIO_SYSSPACE,&nc,&cp,&cc);
-	    na++;
-	    /* remove argv[0] b/c we just placed it in the arg list. */
-	    uap->argp++;
-	    if (error) goto bad;
-	    /* Copy the argument in the interpreter first line if there
-	     * was one. 
-	     */
-	    if (cfarg[0]) {
-	      error = copyArgument(cfarg,UIO_SYSSPACE,&nc,&cp,&cc);
-	      na++;
-	      if (error) goto bad;
-	    }
-	    
-	    /* copy the name of the file being interpreted, gotten from
-	     * the structures passed in to execve.
-	     */
-	    error = copyArgument(uap->fname,UIO_USERSPACE,&nc,&cp,&cc);
-	    na++;
-	  }
-	  /* Now, get rest of arguments */
-	  while (uap->argp != NULL) {
-	    char* userArgument = (char*)fuword((caddr_t) uap->argp);
-	    uap->argp++;
-	    if (userArgument == NULL) {
-	      break;
-	    } else if ((int)userArgument == -1) {
-	      /* Um... why would it be -1? */
-	      error = EFAULT;
-	      goto bad;
-	    }
-	    error = copyArgument(userArgument, UIO_USERSPACE,&nc,&cp,&cc);
-	    if (error) goto bad;
-	    na++;
-	  }	 
-	  /* Now, get the environment */
-	  while (uap->envp != NULL) {
-	    char *userEnv = (char*) fuword((caddr_t) uap->envp);
-	    uap->envp++;
-	    if (userEnv == NULL) {
-	      break;
-	    } else if ((int)userEnv == -1) {
-	      error = EFAULT;
-	      goto bad;
-	    }
-	    error = copyArgument(userEnv,UIO_USERSPACE,&nc,&cp,&cc);
-	    if (error) goto bad;
-	    na++;
-	    ne++;
-	  }
-	}
-
-	/* make sure there are nulls are the end!! */
-	{
-		int	cnt = 3;
-		char *mp = cp;
 
-		while ( cnt-- )
-			*mp++ = '\0';	
+		/* Requested binary preference was not honored */
+		error = EBADEXEC;
+		goto bad;
 	}
 
-	/* and round up count of bytes written to next word. */
-	nc = (nc + NBPW-1) & ~(NBPW-1);
+regular_grading:
+	/* Look up our preferred architecture in the fat file. */
+	lret = fatfile_getbestarch((vm_offset_t)fat_header,
+	    PAGE_SIZE,
+	    imgp,
+	    &fat_arch);
+	if (lret != LOAD_SUCCESS) {
+		error = load_return_to_errno(lret);
+		goto bad;
+	}
 
-	if (vattr.va_fsid == classichandler_fsid &&
-		vattr.va_fileid == classichandler_fileid) {
-		executingClassic = 1;
+use_arch:
+	/* Read the Mach-O header out of fat_arch */
+	error = vn_rdwr(UIO_READ, imgp->ip_vp, imgp->ip_vdata,
+	    PAGE_SIZE, fat_arch.offset,
+	    UIO_SYSSPACE, (IO_UNIT | IO_NODELOCKED),
+	    cred, &resid, p);
+	if (error) {
+		goto bad;
 	}
 
-	if (vfexec) {
- 		kern_return_t	result;
-
-		result = task_create_internal(task, FALSE, &new_task);
-		if (result != KERN_SUCCESS)
-	    	printf("execve: task_create failed. Code: 0x%x\n", result);
-		p->task = new_task;
-		set_bsdtask_info(new_task, p);
-		if (p->p_nice != 0)
-			resetpriority(p);
-		task = new_task;
-		map = get_task_map(new_task);
-		result = thread_create(new_task, &thr_act);
-		if (result != KERN_SUCCESS)
-	    	printf("execve: thread_create failed. Code: 0x%x\n", result);
-		uthread = get_bsdthread_info(thr_act);
-	} else {
-		map = VM_MAP_NULL;
+	if (resid) {
+		memset(imgp->ip_vdata + (PAGE_SIZE - resid), 0x0, resid);
 	}
 
-	/*
-	 *	Load the Mach-O file.
-	 */
-	VOP_UNLOCK(vp, 0, p);	/* XXX */
-	if(ws_cache_name) {
-		tws_handle_startup_file(task, cred->cr_uid, 
-			ws_cache_name, vp, &clean_regions);
-	}
-
-	vm_get_shared_region(task, &initial_region);
-    int parentIsClassic = (p->p_flag & P_CLASSIC);
-	struct vnode *rootDir = p->p_fd->fd_rdir;
-
-	if ((parentIsClassic && !executingClassic) ||
-		(!parentIsClassic && executingClassic)) {
-		shared_region = lookup_default_shared_region(
-				(int)rootDir,
-				(executingClassic ?
-				CPU_TYPE_POWERPC :
-				machine_slot[cpu_number()].cpu_type));
-		if (shared_region == NULL) {
-			shared_region_mapping_t old_region;
-			shared_region_mapping_t new_region;
-			vm_get_shared_region(current_task(), &old_region);
-			/* grrrr... this sets current_task(), not task
-			* -- they're different (usually)
-			*/
-			shared_file_boot_time_init(
-				(int)rootDir,
-				(executingClassic ?
-				CPU_TYPE_POWERPC :
-				machine_slot[cpu_number()].cpu_type));
-			if ( current_task() != task ) {
-				vm_get_shared_region(current_task(),&new_region);
-				vm_set_shared_region(task,new_region);
-				vm_set_shared_region(current_task(),old_region);
-			}
-		} else {
-			vm_set_shared_region(task, shared_region);
-		}
-		shared_region_mapping_dealloc(initial_region);
+	/* Success.  Indicate we have identified an encapsulated binary */
+	error = -2;
+	imgp->ip_arch_offset = (user_size_t)fat_arch.offset;
+	imgp->ip_arch_size = (user_size_t)fat_arch.size;
+	imgp->ip_origcputype = fat_arch.cputype;
+	imgp->ip_origcpusubtype = fat_arch.cpusubtype;
+
+bad:
+	kauth_cred_unref(&cred);
+	return error;
+}
+
+static int
+activate_exec_state(task_t task, proc_t p, thread_t thread, load_result_t *result)
+{
+	int ret;
+
+	task_set_dyld_info(task, MACH_VM_MIN_ADDRESS, 0);
+	task_set_64bit(task, result->is_64bit_addr, result->is_64bit_data);
+	if (result->is_64bit_addr) {
+		OSBitOrAtomic(P_LP64, &p->p_flag);
+	} else {
+		OSBitAndAtomic(~((uint32_t)P_LP64), &p->p_flag);
 	}
-	
-	lret = load_machfile(vp, mach_header, arch_offset,
-		arch_size, &load_result, thr_act, map, clean_regions);
+	task_set_mach_header_address(task, result->mach_header);
 
-	if (lret != LOAD_SUCCESS) {
-		error = load_return_to_errno(lret);
-		vrele(vp);
-		vp = NULL;
-		goto badtoolate;
+	ret = thread_state_initialize(thread);
+	if (ret != KERN_SUCCESS) {
+		return ret;
 	}
 
-	/* load_machfile() maps the vnode */
-	ubc_map(vp);
+	if (result->threadstate) {
+		uint32_t *ts = result->threadstate;
+		uint32_t total_size = result->threadstate_sz;
 
-	/*
-	 * deal with set[ug]id.
-	 */
-	p->p_flag &= ~P_SUGID;
-	if (((origvattr.va_mode & VSUID) != 0 &&
-	    p->p_ucred->cr_uid != origvattr.va_uid)
-	    || (origvattr.va_mode & VSGID) != 0 &&
-	    p->p_ucred->cr_gid != origvattr.va_gid) {
-		p->p_ucred = crcopy(cred);
-#if KTRACE
-		/*
-		 * If process is being ktraced, turn off - unless
-		 * root set it.
-		 */
-		if (p->p_tracep && !(p->p_traceflag & KTRFAC_ROOT)) {
-			struct vnode *tvp = p->p_tracep;
-			p->p_tracep = NULL;
-			p->p_traceflag = 0;
+		while (total_size > 0) {
+			uint32_t flavor = *ts++;
+			uint32_t size = *ts++;
 
-			if (UBCINFOEXISTS(tvp))
-			        ubc_rele(tvp);
-			vrele(tvp);
+			ret = thread_setstatus(thread, flavor, (thread_state_t)ts, size);
+			if (ret) {
+				return ret;
+			}
+			ts += size;
+			total_size -= (size + 2) * sizeof(uint32_t);
 		}
-#endif
-		if (origvattr.va_mode & VSUID)
-			p->p_ucred->cr_uid = origvattr.va_uid;
-		if (origvattr.va_mode & VSGID)
-			p->p_ucred->cr_gid = origvattr.va_gid;
+	}
 
-		/*
-		 * Have mach reset the task port.  We don't want
-		 * anyone who had the task port before a setuid
-		 * exec to be able to access/control the task
-		 * after.
-		 */
-		ipc_task_reset(task);
+	thread_setentrypoint(thread, result->entry_point);
 
-		p->p_flag |= P_SUGID;
-
-		/* Radar 2261856; setuid security hole fix */
-		/* Patch from OpenBSD: A. Ramesh */
-		/*
-		 * XXX For setuid processes, attempt to ensure that
-		 * stdin, stdout, and stderr are already allocated.
-		 * We do not want userland to accidentally allocate
-		 * descriptors in this range which has implied meaning
-		 * to libc.
-		 */
-		for (i = 0; i < 3; i++) {
-			extern struct fileops vnops;
-			struct nameidata nd1;
-			struct file *fp;
-			int indx;
-
-			if (p->p_fd->fd_ofiles[i] == NULL) {
-				if ((error = falloc(p, &fp, &indx)) != 0)
-					continue;
-				NDINIT(&nd1, LOOKUP, FOLLOW, UIO_SYSSPACE,
-				    "/dev/null", p);
-				if ((error = vn_open(&nd1, FREAD, 0)) != 0) {
-					ffree(fp);
-					p->p_fd->fd_ofiles[indx] = NULL;
-					break;
-				}
-				fp->f_flag = FREAD;
-				fp->f_type = DTYPE_VNODE;
-				fp->f_ops = &vnops;
-				fp->f_data = (caddr_t)nd1.ni_vp;
-				VOP_UNLOCK(nd1.ni_vp, 0, p);
-			}
-		}
-	}
-	p->p_cred->p_svuid = p->p_ucred->cr_uid;
-	p->p_cred->p_svgid = p->p_ucred->cr_gid;
-	set_security_token(p);
+	return KERN_SUCCESS;
+}
 
-	KNOTE(&p->p_klist, NOTE_EXEC);
 
-	if (!vfexec && (p->p_flag & P_TRACED))
-		psignal(p, SIGTRAP);
+/*
+ * Set p->p_comm and p->p_name to the name passed to exec
+ */
+static void
+set_proc_name(struct image_params *imgp, proc_t p)
+{
+	int p_name_len = sizeof(p->p_name) - 1;
 
-	if (error) {
-		vrele(vp);
-		vp = NULL;
-		goto badtoolate;
-	}
-	VOP_LOCK(vp,  LK_EXCLUSIVE | LK_RETRY, p); /* XXX */
-	vput(vp);
-	vp = NULL;
-	
-	if (load_result.unixproc &&
-		create_unix_stack(get_task_map(task),
-				  load_result.user_stack, load_result.customstack, p)) {
-		error = load_return_to_errno(LOAD_NOSPACE);
-		goto badtoolate;
+	if (imgp->ip_ndp->ni_cnd.cn_namelen > p_name_len) {
+		imgp->ip_ndp->ni_cnd.cn_namelen = p_name_len;
 	}
 
-	if (vfexec) {
-		uthread->uu_ar0 = (void *)get_user_regs(thr_act);
+	bcopy((caddr_t)imgp->ip_ndp->ni_cnd.cn_nameptr, (caddr_t)p->p_name,
+	    (unsigned)imgp->ip_ndp->ni_cnd.cn_namelen);
+	p->p_name[imgp->ip_ndp->ni_cnd.cn_namelen] = '\0';
+
+	if (imgp->ip_ndp->ni_cnd.cn_namelen > MAXCOMLEN) {
+		imgp->ip_ndp->ni_cnd.cn_namelen = MAXCOMLEN;
 	}
 
+	bcopy((caddr_t)imgp->ip_ndp->ni_cnd.cn_nameptr, (caddr_t)p->p_comm,
+	    (unsigned)imgp->ip_ndp->ni_cnd.cn_namelen);
+	p->p_comm[imgp->ip_ndp->ni_cnd.cn_namelen] = '\0';
+}
+
+/*
+ * exec_mach_imgact
+ *
+ * Image activator for mach-o 1.0 binaries.
+ *
+ * Parameters;	struct image_params *	image parameter block
+ *
+ * Returns:	-1			not a fat binary (keep looking)
+ *		-2			Success: encapsulated binary: reread
+ *		>0			Failure: error number
+ *		EBADARCH		Mach-o binary, but with an unrecognized
+ *					architecture
+ *		ENOMEM			No memory for child process after -
+ *					can only happen after vfork()
+ *
+ * Important:	This image activator is NOT byte order neutral.
+ *
+ * Note:	A return value other than -1 indicates subsequent image
+ *		activators should not be given the opportunity to attempt
+ *		to activate the image.
+ *
+ * TODO:	More gracefully handle failures after vfork
+ */
+static int
+exec_mach_imgact(struct image_params *imgp)
+{
+	struct mach_header *mach_header = (struct mach_header *)imgp->ip_vdata;
+	proc_t                  p = vfs_context_proc(imgp->ip_vfs_context);
+	int                     error = 0;
+	task_t                  task;
+	task_t                  new_task = NULL; /* protected by vfexec */
+	thread_t                thread;
+	struct uthread          *uthread;
+	vm_map_t old_map = VM_MAP_NULL;
+	vm_map_t map = VM_MAP_NULL;
+	load_return_t           lret;
+	load_result_t           load_result = {};
+	struct _posix_spawnattr *psa = NULL;
+	int                     spawn = (imgp->ip_flags & IMGPF_SPAWN);
+	int                     vfexec = (imgp->ip_flags & IMGPF_VFORK_EXEC);
+	int                     exec = (imgp->ip_flags & IMGPF_EXEC);
+	os_reason_t             exec_failure_reason = OS_REASON_NULL;
+
 	/*
-	 * Copy back arglist if necessary.
+	 * make sure it's a Mach-O 1.0 or Mach-O 2.0 binary; the difference
+	 * is a reserved field on the end, so for the most part, we can
+	 * treat them as if they were identical. Reverse-endian Mach-O
+	 * binaries are recognized but not compatible.
 	 */
+	if ((mach_header->magic == MH_CIGAM) ||
+	    (mach_header->magic == MH_CIGAM_64)) {
+		error = EBADARCH;
+		goto bad;
+	}
 
-
-	ucp = (int)p->user_stack;
-	if (vfexec) {
-		old_map = vm_map_switch(get_task_map(task));
+	if ((mach_header->magic != MH_MAGIC) &&
+	    (mach_header->magic != MH_MAGIC_64)) {
+		error = -1;
+		goto bad;
 	}
-	if (load_result.unixproc) {
-		int pathptr;
-		
-		ucp = ucp - nc - NBPW;	/* begining of the STRING AREA */
 
-		/*
-		 * Support for new app package launching for Mac OS X allocates
-		 * the "path" at the begining of the execargs buffer.
-		 * copy it just before the string area.
-		 */
-		len = 0;
-		pathptr = ucp - ((savedpathlen + NBPW-1) & ~(NBPW-1));
-		error = copyoutstr(savedpath, (caddr_t)pathptr,
-					(unsigned)savedpathlen, (size_t *)&len);
-		savedpathlen = (savedpathlen + NBPW-1) & ~(NBPW-1);
+	if (mach_header->filetype != MH_EXECUTE) {
+		error = -1;
+		goto bad;
+	}
 
-		if (error) {
-			if (vfexec)
-				vm_map_switch(old_map);
-			goto badtoolate;
+	if (imgp->ip_origcputype != 0) {
+		/* Fat header previously had an idea about this thin file */
+		if (imgp->ip_origcputype != mach_header->cputype ||
+		    imgp->ip_origcpusubtype != mach_header->cpusubtype) {
+			error = EBADARCH;
+			goto bad;
 		}
+	} else {
+		imgp->ip_origcputype = mach_header->cputype;
+		imgp->ip_origcpusubtype = mach_header->cpusubtype;
+	}
 
-		/*
-		 * Record the size of the arguments area so that
-		 * sysctl_procargs() can return the argument area without having
-		 * to parse the arguments.
-		 */
-		p->p_argslen = (int)p->user_stack - pathptr;
-		p->p_argc = na - ne;	/* save argc for sysctl_procargs() */
+	task = current_task();
+	thread = current_thread();
+	uthread = get_bsdthread_info(thread);
 
-		/* Save a NULL pointer below it */
-		(void) suword((caddr_t)(pathptr - NBPW), 0);
+	if ((mach_header->cputype & CPU_ARCH_ABI64) == CPU_ARCH_ABI64) {
+		imgp->ip_flags |= IMGPF_IS_64BIT_ADDR | IMGPF_IS_64BIT_DATA;
+	}
 
-		/* Save the pointer to "path" just below it */
-		(void) suword((caddr_t)(pathptr - 2*NBPW), pathptr);
+	/* If posix_spawn binprefs exist, respect those prefs. */
+	psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
+	if (psa != NULL && psa->psa_binprefs[0] != 0) {
+		int pr = 0;
+		for (pr = 0; pr < NBINPREFS; pr++) {
+			cpu_type_t pref = psa->psa_binprefs[pr];
+			if (pref == 0) {
+				/* No suitable arch in the pref list */
+				error = EBADARCH;
+				goto bad;
+			}
 
-		/*
-		 * na includes arg[] and env[].
-		 * NBPW for 2 NULL one each ofter arg[argc -1] and env[n]
-		 * NBPW for argc
-		 * skip over saved path, NBPW for pointer to path,
-		 * and NBPW for the NULL after pointer to path.
-		 */
-		ap = ucp - na*NBPW - 3*NBPW - savedpathlen - 2*NBPW;
-#if defined(ppc)
-		thread_setuserstack(thr_act, ap);	/* Set the stack */
-#else
-		uthread->uu_ar0[SP] = ap;
-#endif
-		(void) suword((caddr_t)ap, na-ne); /* argc */
-		nc = 0;
-		cc = 0;
-
-		cp = (char *) execargsp;
-		cc = NCARGS - savedpathlen - 2*NBPW;
-		ps.ps_argvstr = (char *)ucp;	/* first argv string */
-		ps.ps_nargvstr = na - ne;		/* argc */
-		for (;;) {
-			ap += NBPW;
-			if (na == ne) {
-				(void) suword((caddr_t)ap, 0);
-				ap += NBPW;
-				ps.ps_envstr = (char *)ucp;
-				ps.ps_nenvstr = ne;
-			}
-			if (--na < 0)
-				break;
-			(void) suword((caddr_t)ap, ucp);
-			do {
-				error = copyoutstr(cp, (caddr_t)ucp,
-						   (unsigned)cc, (size_t *)&len);
-				ucp += len;
-				cp += len;
-				nc += len;
-				cc -= len;
-			} while (error == ENAMETOOLONG);
-			if (error == EFAULT)
-				break;	/* bad stack - user's problem */
-		}
-		(void) suword((caddr_t)ap, 0);
-	}
-	
-	if (load_result.dynlinker) {
-#if defined(ppc)
-		ap = thread_adjuserstack(thr_act, -4);	/* Adjust the stack */
-#else
-		ap = uthread->uu_ar0[SP] -= 4;
+			if (pref == CPU_TYPE_ANY) {
+				/* Jump to regular grading */
+				goto grade;
+			}
+
+			if (pref == imgp->ip_origcputype) {
+				/* We have a match! */
+				goto grade;
+			}
+		}
+		error = EBADARCH;
+		goto bad;
+	}
+grade:
+	if (!grade_binary(imgp->ip_origcputype, imgp->ip_origcpusubtype & ~CPU_SUBTYPE_MASK, TRUE)) {
+		error = EBADARCH;
+		goto bad;
+	}
+
+	if (validate_potential_simulator_binary(imgp->ip_origcputype, imgp,
+	    imgp->ip_arch_offset, imgp->ip_arch_size) != LOAD_SUCCESS) {
+#if __x86_64__
+		const char *excpath;
+		error = exec_save_path(imgp, imgp->ip_user_fname, imgp->ip_seg, &excpath);
+		os_log_error(OS_LOG_DEFAULT, "Unsupported 32-bit executable: \"%s\"", (error) ? imgp->ip_vp->v_name : excpath);
 #endif
-		(void) suword((caddr_t)ap, load_result.mach_header);
+		error = EBADARCH;
+		goto bad;
 	}
 
-	if (vfexec) {
-		vm_map_switch(old_map);
+#if defined(HAS_APPLE_PAC)
+	assert(mach_header->cputype == CPU_TYPE_ARM64
+	    );
+
+	if (((mach_header->cputype == CPU_TYPE_ARM64 &&
+	    (mach_header->cpusubtype & ~CPU_SUBTYPE_MASK) == CPU_SUBTYPE_ARM64E)
+	    ) && (CPU_SUBTYPE_ARM64_PTR_AUTH_VERSION(mach_header->cpusubtype) == 0)) {
+		imgp->ip_flags &= ~IMGPF_NOJOP;
+	} else {
+		imgp->ip_flags |= IMGPF_NOJOP;
 	}
-#if defined(ppc)
-	thread_setentrypoint(thr_act, load_result.entry_point);	/* Set the entry point */
-#elif defined(i386) 
- 	uthread->uu_ar0[PC] = load_result.entry_point;
-#else
-#error architecture not implemented!
-#endif	
+#endif
 
-	/* Stop profiling */
-	stopprofclock(p);
+	/* Copy in arguments/environment from the old process */
+	error = exec_extract_strings(imgp);
+	if (error) {
+		goto bad;
+	}
 
-	/*
-	 * Reset signal state.
-	 */
-	execsigs(p, thr_act);
+	AUDIT_ARG(argv, imgp->ip_startargv, imgp->ip_argc,
+	    imgp->ip_endargv - imgp->ip_startargv);
+	AUDIT_ARG(envv, imgp->ip_endargv, imgp->ip_envc,
+	    imgp->ip_endenvv - imgp->ip_endargv);
 
 	/*
-	 * Close file descriptors
-	 * which specify close-on-exec.
+	 * We are being called to activate an image subsequent to a vfork()
+	 * operation; in this case, we know that our task, thread, and
+	 * uthread are actually those of our parent, and our proc, which we
+	 * obtained indirectly from the image_params vfs_context_t, is the
+	 * new child process.
 	 */
-	fdexec(p);
+	if (vfexec) {
+		imgp->ip_new_thread = fork_create_child(task,
+		    NULL,
+		    p,
+		    FALSE,
+		    (imgp->ip_flags & IMGPF_IS_64BIT_ADDR),
+		    (imgp->ip_flags & IMGPF_IS_64BIT_DATA),
+		    FALSE);
+		/* task and thread ref returned, will be released in __mac_execve */
+		if (imgp->ip_new_thread == NULL) {
+			error = ENOMEM;
+			goto bad;
+		}
+	}
 
-	/*
-	 * need to cancel async IO requests that can be cancelled and wait for those
-	 * already active.  MAY BLOCK!
-	 */
-	_aio_exec( p );
 
-	/* FIXME: Till vmspace inherit is fixed: */
-	if (!vfexec && p->vm_shm)
-		shmexec(p);
-	/* Clean up the semaphores */
-	semexit(p);
+	/* reset local idea of thread, uthread, task */
+	thread = imgp->ip_new_thread;
+	uthread = get_bsdthread_info(thread);
+	task = new_task = get_threadtask(thread);
 
 	/*
-	 * Remember file name for accounting.
-	 */
-	p->p_acflag &= ~AFORK;
-	/* If the translated name isn't NULL, then we want to use
-	 * that translated name as the name we show as the "real" name.
-	 * Otherwise, use the name passed into exec.
+	 *	Load the Mach-O file.
+	 *
+	 * NOTE: An error after this point  indicates we have potentially
+	 * destroyed or overwritten some process state while attempting an
+	 * execve() following a vfork(), which is an unrecoverable condition.
+	 * We send the new process an immediate SIGKILL to avoid it executing
+	 * any instructions in the mutated address space. For true spawns,
+	 * this is not the case, and "too late" is still not too late to
+	 * return an error code to the parent process.
 	 */
-	if (0 != binaryWithClassicName[0]) {
-		bcopy((caddr_t)binaryWithClassicName, (caddr_t)p->p_comm,
-			sizeof(binaryWithClassicName));
-	} else {
-		if (nd.ni_cnd.cn_namelen > MAXCOMLEN)
-			nd.ni_cnd.cn_namelen = MAXCOMLEN;
-		bcopy((caddr_t)nd.ni_cnd.cn_nameptr, (caddr_t)p->p_comm,
-			(unsigned)nd.ni_cnd.cn_namelen);
-		p->p_comm[nd.ni_cnd.cn_namelen] = '\0';
-	}
 
-	{
-	  /* This is for kdebug */
-	  long dbg_arg1, dbg_arg2, dbg_arg3, dbg_arg4;
+	/*
+	 * Actually load the image file we previously decided to load.
+	 */
+	lret = load_machfile(imgp, mach_header, thread, &map, &load_result);
+	if (lret != LOAD_SUCCESS) {
+		error = load_return_to_errno(lret);
 
-	  /* Collect the pathname for tracing */
-	  kdbg_trace_string(p, &dbg_arg1, &dbg_arg2, &dbg_arg3, &dbg_arg4);
+		KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
+		    p->p_pid, OS_REASON_EXEC, EXEC_EXIT_REASON_BAD_MACHO, 0, 0);
+		if (lret == LOAD_BADMACHO_UPX) {
+			set_proc_name(imgp, p);
+			exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_UPX);
+			exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
+		} else {
+			exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_BAD_MACHO);
 
+			if (bootarg_execfailurereports) {
+				set_proc_name(imgp, p);
+				exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
+			}
+		}
 
+		exec_failure_reason->osr_flags |= OS_REASON_FLAG_CONSISTENT_FAILURE;
 
-	  if (vfexec)
-	  {
-		  KERNEL_DEBUG_CONSTANT1((TRACEDBG_CODE(DBG_TRACE_DATA, 2)) | DBG_FUNC_NONE,
-		                        p->p_pid ,0,0,0, (unsigned int)thr_act);
-	          KERNEL_DEBUG_CONSTANT1((TRACEDBG_CODE(DBG_TRACE_STRING, 2)) | DBG_FUNC_NONE,
-					dbg_arg1, dbg_arg2, dbg_arg3, dbg_arg4, (unsigned int)thr_act);
-	  }
-	  else
-	  {
-		  KERNEL_DEBUG_CONSTANT((TRACEDBG_CODE(DBG_TRACE_DATA, 2)) | DBG_FUNC_NONE,
-		                        p->p_pid ,0,0,0,0);
-	          KERNEL_DEBUG_CONSTANT((TRACEDBG_CODE(DBG_TRACE_STRING, 2)) | DBG_FUNC_NONE,
-					dbg_arg1, dbg_arg2, dbg_arg3, dbg_arg4, 0);
-	  }
+		goto badtoolate;
 	}
 
-	if (executingClassic)
-		p->p_flag |= P_CLASSIC | P_AFFINITY;
-	else
-		p->p_flag &= ~P_CLASSIC;
+	proc_lock(p);
+	p->p_cputype = imgp->ip_origcputype;
+	p->p_cpusubtype = imgp->ip_origcpusubtype;
+	p->p_platform = load_result.ip_platform;
+	p->p_sdk = load_result.lr_sdk;
+	proc_unlock(p);
+
+	vm_map_set_user_wire_limit(map, p->p_rlimit[RLIMIT_MEMLOCK].rlim_cur);
 
 	/*
-	 * mark as execed, wakeup the process that vforked (if any) and tell
-	 * it that it now has it's own resources back
+	 * Set code-signing flags if this binary is signed, or if parent has
+	 * requested them on exec.
 	 */
-	p->p_flag |= P_EXEC;
-	if (p->p_pptr && (p->p_flag & P_PPWAIT)) {
-		p->p_flag &= ~P_PPWAIT;
-		wakeup((caddr_t)p->p_pptr);
+	if (load_result.csflags & CS_VALID) {
+		imgp->ip_csflags |= load_result.csflags &
+		    (CS_VALID | CS_SIGNED | CS_DEV_CODE |
+		    CS_HARD | CS_KILL | CS_RESTRICT | CS_ENFORCEMENT | CS_REQUIRE_LV |
+		    CS_FORCED_LV | CS_ENTITLEMENTS_VALIDATED | CS_DYLD_PLATFORM | CS_RUNTIME |
+		    CS_ENTITLEMENT_FLAGS |
+		    CS_EXEC_SET_HARD | CS_EXEC_SET_KILL | CS_EXEC_SET_ENFORCEMENT);
+	} else {
+		imgp->ip_csflags &= ~CS_VALID;
 	}
 
-	if (vfexec && (p->p_flag & P_TRACED)) {
-			psignal_vfork(p, new_task, thr_act, SIGTRAP);
+	if (p->p_csflags & CS_EXEC_SET_HARD) {
+		imgp->ip_csflags |= CS_HARD;
+	}
+	if (p->p_csflags & CS_EXEC_SET_KILL) {
+		imgp->ip_csflags |= CS_KILL;
+	}
+	if (p->p_csflags & CS_EXEC_SET_ENFORCEMENT) {
+		imgp->ip_csflags |= CS_ENFORCEMENT;
+	}
+	if (p->p_csflags & CS_EXEC_INHERIT_SIP) {
+		if (p->p_csflags & CS_INSTALLER) {
+			imgp->ip_csflags |= CS_INSTALLER;
+		}
+		if (p->p_csflags & CS_DATAVAULT_CONTROLLER) {
+			imgp->ip_csflags |= CS_DATAVAULT_CONTROLLER;
+		}
+		if (p->p_csflags & CS_NVRAM_UNRESTRICTED) {
+			imgp->ip_csflags |= CS_NVRAM_UNRESTRICTED;
+		}
 	}
 
-badtoolate:
-	if (vfexec) {
-		task_deallocate(new_task);
-		act_deallocate(thr_act);
-		if (error)
-			error = 0;
+	/*
+	 * Set up the system reserved areas in the new address space.
+	 */
+	int cpu_subtype;
+	cpu_subtype = 0; /* all cpu_subtypes use the same shared region */
+#if defined(HAS_APPLE_PAC)
+	if (cpu_type() == CPU_TYPE_ARM64 &&
+	    (p->p_cpusubtype & ~CPU_SUBTYPE_MASK) == CPU_SUBTYPE_ARM64E) {
+		assertf(p->p_cputype == CPU_TYPE_ARM64,
+		    "p %p cpu_type() 0x%x p->p_cputype 0x%x p->p_cpusubtype 0x%x",
+		    p, cpu_type(), p->p_cputype, p->p_cpusubtype);
+		/*
+		 * arm64e uses pointer authentication, so request a separate
+		 * shared region for this CPU subtype.
+		 */
+		cpu_subtype = p->p_cpusubtype & ~CPU_SUBTYPE_MASK;
 	}
-bad:
-	FREE_ZONE(nd.ni_cnd.cn_pnbuf, nd.ni_cnd.cn_pnlen, M_NAMEI);
-	if (vp)
-		vput(vp);
-bad1:
-	if (execargs)
-		execargs_free(execargs);
-	if (!error && vfexec) {
-			vfork_return(current_act(), p->p_pptr, p, retval);
-			(void) thread_resume(thr_act);
-			return(0);
-	}
-	return(error);
-}
+#endif /* HAS_APPLE_PAC */
+	vm_map_exec(map, task, load_result.is_64bit_addr, (void *)p->p_fd->fd_rdir, cpu_type(), cpu_subtype);
 
+	/*
+	 * Close file descriptors which specify close-on-exec.
+	 */
+	fdexec(p, psa != NULL ? psa->psa_flags : 0, exec);
 
-#define	unix_stack_size(p)	(p->p_rlimit[RLIMIT_STACK].rlim_cur)
+	/*
+	 * deal with set[ug]id.
+	 */
+	error = exec_handle_sugid(imgp);
+	if (error) {
+		vm_map_deallocate(map);
 
-kern_return_t
-create_unix_stack(map, user_stack, customstack, p)
-	vm_map_t	map;
-	vm_offset_t	user_stack;
-	int			customstack;
-	struct proc	*p;
-{
-	vm_size_t	size;
-	vm_offset_t	addr;
-
-	p->user_stack = (caddr_t)user_stack;
-	if (!customstack) {
-		size = round_page_64(unix_stack_size(p));
-		addr = trunc_page_32(user_stack - size);
-		return (vm_allocate(map, &addr, size,
-					VM_MAKE_TAG(VM_MEMORY_STACK) | FALSE));
-	} else
-		return(KERN_SUCCESS);
-}
+		KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
+		    p->p_pid, OS_REASON_EXEC, EXEC_EXIT_REASON_SUGID_FAILURE, 0, 0);
 
-#include <sys/reboot.h>
+		exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_SUGID_FAILURE);
+		if (bootarg_execfailurereports) {
+			set_proc_name(imgp, p);
+			exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
+		}
 
-char		init_program_name[128] = "/sbin/mach_init\0";
+		goto badtoolate;
+	}
 
-char		init_args[128] = "";
+	/*
+	 * Commit to new map.
+	 *
+	 * Swap the new map for the old for target task, which consumes
+	 * our new map reference but each leaves us responsible for the
+	 * old_map reference.  That lets us get off the pmap associated
+	 * with it, and then we can release it.
+	 *
+	 * The map needs to be set on the target task which is different
+	 * than current task, thus swap_task_map is used instead of
+	 * vm_map_switch.
+	 */
+	old_map = swap_task_map(task, thread, map);
+	vm_map_deallocate(old_map);
+	old_map = NULL;
+
+	lret = activate_exec_state(task, p, thread, &load_result);
+	if (lret != KERN_SUCCESS) {
+		KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
+		    p->p_pid, OS_REASON_EXEC, EXEC_EXIT_REASON_ACTV_THREADSTATE, 0, 0);
+
+		exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_ACTV_THREADSTATE);
+		if (bootarg_execfailurereports) {
+			set_proc_name(imgp, p);
+			exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
+		}
 
-struct execve_args	init_exec_args;
-int		init_attempts = 0;
+		goto badtoolate;
+	}
 
+	/*
+	 * deal with voucher on exec-calling thread.
+	 */
+	if (imgp->ip_new_thread == NULL) {
+		thread_set_mach_voucher(current_thread(), IPC_VOUCHER_NULL);
+	}
 
-void
-load_init_program(p)
-	struct proc *p;
-{
-	vm_offset_t	init_addr;
-	int		*old_ap;
-	char		*argv[3];
-	int		error;
-	register_t retval[2];
-	struct uthread * ut;
+	/* Make sure we won't interrupt ourself signalling a partial process */
+	if (!vfexec && !spawn && (p->p_lflag & P_LTRACED)) {
+		psignal(p, SIGTRAP);
+	}
+
+	if (load_result.unixproc &&
+	    create_unix_stack(get_task_map(task),
+	    &load_result,
+	    p) != KERN_SUCCESS) {
+		error = load_return_to_errno(LOAD_NOSPACE);
 
-	error = 0;
+		KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
+		    p->p_pid, OS_REASON_EXEC, EXEC_EXIT_REASON_STACK_ALLOC, 0, 0);
 
-	/* init_args are copied in string form directly from bootstrap */
-	
-	do {
-		if (boothowto & RB_INITNAME) {
-			printf("init program? ");
-#if FIXME  /* [ */
-			gets(init_program_name, init_program_name);
-#endif  /* FIXME ] */
-		}
-
-		if (error && ((boothowto & RB_INITNAME) == 0) &&
-					(init_attempts == 1)) {
-			static char other_init[] = "/etc/mach_init";
-			printf("Load of %s, errno %d, trying %s\n",
-				init_program_name, error, other_init);
-			error = 0;
-			bcopy(other_init, init_program_name,
-							sizeof(other_init));
+		exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_STACK_ALLOC);
+		if (bootarg_execfailurereports) {
+			set_proc_name(imgp, p);
+			exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
 		}
 
-		init_attempts++;
+		goto badtoolate;
+	}
 
-		if (error) {
-			printf("Load of %s failed, errno %d\n",
-					init_program_name, error);
-			error = 0;
-			boothowto |= RB_INITNAME;
-			continue;
-		}
+	error = exec_add_apple_strings(imgp, &load_result);
+	if (error) {
+		KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
+		    p->p_pid, OS_REASON_EXEC, EXEC_EXIT_REASON_APPLE_STRING_INIT, 0, 0);
 
-		/*
-		 *	Copy out program name.
-		 */
+		exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_APPLE_STRING_INIT);
+		if (bootarg_execfailurereports) {
+			set_proc_name(imgp, p);
+			exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
+		}
+		goto badtoolate;
+	}
 
-		init_addr = VM_MIN_ADDRESS;
-		(void) vm_allocate(current_map(), &init_addr,
-				   PAGE_SIZE, TRUE);
-		if (init_addr == 0)
-			init_addr++;
-		(void) copyout((caddr_t) init_program_name,
-				(caddr_t) (init_addr),
-				(unsigned) sizeof(init_program_name)+1);
+	/* Switch to target task's map to copy out strings */
+	old_map = vm_map_switch(get_task_map(task));
 
-		argv[0] = (char *) init_addr;
-		init_addr += sizeof(init_program_name);
-		init_addr = (vm_offset_t)ROUND_PTR(char, init_addr);
+	if (load_result.unixproc) {
+		user_addr_t     ap;
 
 		/*
-		 *	Put out first (and only) argument, similarly.
-		 *	Assumes everything fits in a page as allocated
-		 *	above.
+		 * Copy the strings area out into the new process address
+		 * space.
 		 */
+		ap = p->user_stack;
+		error = exec_copyout_strings(imgp, &ap);
+		if (error) {
+			vm_map_switch(old_map);
 
-		(void) copyout((caddr_t) init_args,
-				(caddr_t) (init_addr),
-				(unsigned) sizeof(init_args));
-
-		argv[1] = (char *) init_addr;
-		init_addr += sizeof(init_args);
-		init_addr = (vm_offset_t)ROUND_PTR(char, init_addr);
+			KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
+			    p->p_pid, OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_STRINGS, 0, 0);
 
-		/*
-		 *	Null-end the argument list
-		 */
+			exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_STRINGS);
+			if (bootarg_execfailurereports) {
+				set_proc_name(imgp, p);
+				exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
+			}
+			goto badtoolate;
+		}
+		/* Set the stack */
+		thread_setuserstack(thread, ap);
+	}
 
-		argv[2] = (char *) 0;
-		
-		/*
-		 *	Copy out the argument list.
-		 */
-		
-		(void) copyout((caddr_t) argv,
-				(caddr_t) (init_addr),
-				(unsigned) sizeof(argv));
+	if (load_result.dynlinker) {
+		uint64_t        ap;
+		int                     new_ptr_size = (imgp->ip_flags & IMGPF_IS_64BIT_ADDR) ? 8 : 4;
 
-		/*
-		 *	Set up argument block for fake call to execve.
-		 */
+		/* Adjust the stack */
+		ap = thread_adjuserstack(thread, -new_ptr_size);
+		error = copyoutptr(load_result.mach_header, ap, new_ptr_size);
 
-		init_exec_args.fname = argv[0];
-		init_exec_args.argp = (char **) init_addr;
-		init_exec_args.envp = 0;
-		
-		/* So that mach_init task 
-		 * is set with uid,gid 0 token 
-		 */
-		set_security_token(p);
+		if (error) {
+			vm_map_switch(old_map);
 
-		error = execve(p,&init_exec_args,retval);
-	} while (error);
-}
+			KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
+			    p->p_pid, OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_DYNLINKER, 0, 0);
 
-/*
- * Convert a load_return_t to an errno.
- */
-static int 
-load_return_to_errno(load_return_t lrtn)
-{
-	switch (lrtn) {
-	    case LOAD_SUCCESS:
-			return 0;
-	    case LOAD_BADARCH:
-	    	return EBADARCH;
-	    case LOAD_BADMACHO:
-	    	return EBADMACHO;
-	    case LOAD_SHLIB:
-	    	return ESHLIBVERS;
-	    case LOAD_NOSPACE:
-	    case LOAD_RESOURCE:
-	    	return ENOMEM;
-	    case LOAD_PROTECT:
-	    	return EACCES;
-		case LOAD_ENOENT:
-			return ENOENT;
-		case LOAD_IOERROR:
-			return EIO;
-	    case LOAD_FAILURE:
-	    default:
-	    	return EBADEXEC;
+			exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_DYNLINKER);
+			if (bootarg_execfailurereports) {
+				set_proc_name(imgp, p);
+				exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
+			}
+			goto badtoolate;
+		}
+		task_set_dyld_info(task, load_result.all_image_info_addr,
+		    load_result.all_image_info_size);
 	}
-}
 
-/*
- * exec_check_access()
- */
-int
-check_exec_access(p, vp, vap)
-	struct proc  *p;
-	struct vnode *vp;
-	struct vattr *vap;
-{
-	int flag;
-	int error;
+	/* Avoid immediate VM faults back into kernel */
+	exec_prefault_data(p, imgp, &load_result);
 
-	if (error = VOP_ACCESS(vp, VEXEC, p->p_ucred, p))
-		return (error);
-	flag = p->p_flag;
-	if (flag & P_TRACED) {
-		if (error = VOP_ACCESS(vp, VREAD, p->p_ucred, p))
-			return (error);
-	}
-	if (vp->v_type != VREG ||
-	    (vap->va_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) == 0)
-		return (EACCES);
-	return (0);
-}
+	vm_map_switch(old_map);
 
-#include <mach/mach_types.h>
-#include <mach/vm_prot.h>
-#include <mach/semaphore.h>
-#include <mach/sync_policy.h>
-#include <kern/clock.h>
-#include <mach/kern_return.h>
+	/*
+	 * Reset signal state.
+	 */
+	execsigs(p, thread);
+
+	/*
+	 * need to cancel async IO requests that can be cancelled and wait for those
+	 * already active.  MAY BLOCK!
+	 */
+	_aio_exec( p );
 
-extern semaphore_t execve_semaphore;
+#if SYSV_SHM
+	/* FIXME: Till vmspace inherit is fixed: */
+	if (!vfexec && p->vm_shm) {
+		shmexec(p);
+	}
+#endif
+#if SYSV_SEM
+	/* Clean up the semaphores */
+	semexit(p);
+#endif
 
-static int
-execargs_alloc(addrp)
-	vm_offset_t	*addrp;
-{
-	kern_return_t kret;
+	/*
+	 * Remember file name for accounting.
+	 */
+	p->p_acflag &= ~AFORK;
 
-	kret = semaphore_wait(execve_semaphore);
-	if (kret != KERN_SUCCESS)
-		switch (kret) {
-		default:
-			return (EINVAL);
-		case KERN_INVALID_ADDRESS:
-		case KERN_PROTECTION_FAILURE:
-			return (EACCES);
-		case KERN_ABORTED:
-		case KERN_OPERATION_TIMED_OUT:
-			return (EINTR);
+	set_proc_name(imgp, p);
+
+#if CONFIG_SECLUDED_MEMORY
+	if (secluded_for_apps &&
+	    load_result.platform_binary) {
+		if (strncmp(p->p_name,
+		    "Camera",
+		    sizeof(p->p_name)) == 0) {
+			task_set_could_use_secluded_mem(task, TRUE);
+		} else {
+			task_set_could_use_secluded_mem(task, FALSE);
+		}
+		if (strncmp(p->p_name,
+		    "mediaserverd",
+		    sizeof(p->p_name)) == 0) {
+			task_set_could_also_use_secluded_mem(task, TRUE);
 		}
+	}
+#endif /* CONFIG_SECLUDED_MEMORY */
 
-	kret = kmem_alloc_pageable(bsd_pageable_map, addrp, NCARGS);
-	if (kret != KERN_SUCCESS) {
-	        semaphore_signal(execve_semaphore);
-		return (ENOMEM);
+#if __arm64__
+	if (load_result.legacy_footprint) {
+		task_set_legacy_footprint(task);
 	}
-	return (0);
-}
+#endif /* __arm64__ */
 
-static int
-execargs_free(addr)
-	vm_offset_t	addr;
-{
-	kern_return_t kret;
+	pal_dbg_set_task_name(task);
 
-	kmem_free(bsd_pageable_map, addr, NCARGS);
+	/*
+	 * The load result will have already been munged by AMFI to include the
+	 * platform binary flag if boot-args dictated it (AMFI will mark anything
+	 * that doesn't go through the upcall path as a platform binary if its
+	 * enforcement is disabled).
+	 */
+	if (load_result.platform_binary) {
+		if (cs_debug) {
+			printf("setting platform binary on task: pid = %d\n", p->p_pid);
+		}
 
-	kret = semaphore_signal(execve_semaphore);
-	switch (kret) { 
-	case KERN_INVALID_ADDRESS:
-	case KERN_PROTECTION_FAILURE:
-		return (EINVAL);
-	case KERN_ABORTED:
-	case KERN_OPERATION_TIMED_OUT:
-		return (EINTR);
-	case KERN_SUCCESS:
-		return(0);
-	default:
-		return (EINVAL);
+		/*
+		 * We must use 'task' here because the proc's task has not yet been
+		 * switched to the new one.
+		 */
+		task_set_platform_binary(task, TRUE);
+	} else {
+		if (cs_debug) {
+			printf("clearing platform binary on task: pid = %d\n", p->p_pid);
+		}
+
+		task_set_platform_binary(task, FALSE);
+	}
+
+#if DEVELOPMENT || DEBUG
+	/*
+	 * Update the pid an proc name for importance base if any
+	 */
+	task_importance_update_owner_info(task);
+#endif
+
+	memcpy(&p->p_uuid[0], &load_result.uuid[0], sizeof(p->p_uuid));
+
+#if CONFIG_DTRACE
+	dtrace_proc_exec(p);
+#endif
+
+	if (kdebug_enable) {
+		long args[4] = {};
+
+		uintptr_t fsid = 0, fileid = 0;
+		if (imgp->ip_vattr) {
+			uint64_t fsid64 = vnode_get_va_fsid(imgp->ip_vattr);
+			fsid   = fsid64;
+			fileid = imgp->ip_vattr->va_fileid;
+			// check for (unexpected) overflow and trace zero in that case
+			if (fsid != fsid64 || fileid != imgp->ip_vattr->va_fileid) {
+				fsid = fileid = 0;
+			}
+		}
+		KERNEL_DEBUG_CONSTANT_IST1(TRACE_DATA_EXEC, p->p_pid, fsid, fileid, 0,
+		    (uintptr_t)thread_tid(thread));
+
+		/*
+		 * Collect the pathname for tracing
+		 */
+		kdbg_trace_string(p, &args[0], &args[1], &args[2], &args[3]);
+		KERNEL_DEBUG_CONSTANT_IST1(TRACE_STRING_EXEC, args[0], args[1],
+		    args[2], args[3], (uintptr_t)thread_tid(thread));
+	}
+
+	/*
+	 * If posix_spawned with the START_SUSPENDED flag, stop the
+	 * process before it runs.
+	 */
+	if (imgp->ip_px_sa != NULL) {
+		psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
+		if (psa->psa_flags & POSIX_SPAWN_START_SUSPENDED) {
+			proc_lock(p);
+			p->p_stat = SSTOP;
+			proc_unlock(p);
+			(void) task_suspend_internal(task);
+		}
+	}
+
+	/*
+	 * mark as execed, wakeup the process that vforked (if any) and tell
+	 * it that it now has its own resources back
+	 */
+	OSBitOrAtomic(P_EXEC, &p->p_flag);
+	proc_resetregister(p);
+	if (p->p_pptr && (p->p_lflag & P_LPPWAIT)) {
+		proc_lock(p);
+		p->p_lflag &= ~P_LPPWAIT;
+		proc_unlock(p);
+		wakeup((caddr_t)p->p_pptr);
+	}
+
+	/*
+	 * Pay for our earlier safety; deliver the delayed signals from
+	 * the incomplete vfexec process now that it's complete.
+	 */
+	if (vfexec && (p->p_lflag & P_LTRACED)) {
+		psignal_vfork(p, new_task, thread, SIGTRAP);
+	}
+
+	goto done;
+
+badtoolate:
+	/* Don't allow child process to execute any instructions */
+	if (!spawn) {
+		if (vfexec) {
+			assert(exec_failure_reason != OS_REASON_NULL);
+			psignal_vfork_with_reason(p, new_task, thread, SIGKILL, exec_failure_reason);
+			exec_failure_reason = OS_REASON_NULL;
+		} else {
+			assert(exec_failure_reason != OS_REASON_NULL);
+			psignal_with_reason(p, SIGKILL, exec_failure_reason);
+			exec_failure_reason = OS_REASON_NULL;
+
+			if (exec) {
+				/* Terminate the exec copy task */
+				task_terminate_internal(task);
+			}
+		}
+
+		/* We can't stop this system call at this point, so just pretend we succeeded */
+		error = 0;
+	} else {
+		os_reason_free(exec_failure_reason);
+		exec_failure_reason = OS_REASON_NULL;
+	}
+
+done:
+	if (load_result.threadstate) {
+		kfree(load_result.threadstate, load_result.threadstate_sz);
+		load_result.threadstate = NULL;
+	}
+
+bad:
+	/* If we hit this, we likely would have leaked an exit reason */
+	assert(exec_failure_reason == OS_REASON_NULL);
+	return error;
+}
+
+
+
+
+/*
+ * Our image activator table; this is the table of the image types we are
+ * capable of loading.  We list them in order of preference to ensure the
+ * fastest image load speed.
+ *
+ * XXX hardcoded, for now; should use linker sets
+ */
+struct execsw {
+	int(*const ex_imgact)(struct image_params *);
+	const char *ex_name;
+}const execsw[] = {
+	{ exec_mach_imgact, "Mach-o Binary" },
+	{ exec_fat_imgact, "Fat Binary" },
+	{ exec_shell_imgact, "Interpreter Script" },
+	{ NULL, NULL}
+};
+
+
+/*
+ * exec_activate_image
+ *
+ * Description:	Iterate through the available image activators, and activate
+ *		the image associated with the imgp structure.  We start with
+ *		the activator for Mach-o binaries followed by that for Fat binaries
+ *		for Interpreter scripts.
+ *
+ * Parameters:	struct image_params *	Image parameter block
+ *
+ * Returns:	0			Success
+ *		EBADEXEC		The executable is corrupt/unknown
+ *	execargs_alloc:EINVAL		Invalid argument
+ *	execargs_alloc:EACCES		Permission denied
+ *	execargs_alloc:EINTR		Interrupted function
+ *	execargs_alloc:ENOMEM		Not enough space
+ *	exec_save_path:EFAULT		Bad address
+ *	exec_save_path:ENAMETOOLONG	Filename too long
+ *	exec_check_permissions:EACCES	Permission denied
+ *	exec_check_permissions:ENOEXEC	Executable file format error
+ *	exec_check_permissions:ETXTBSY	Text file busy [misuse of error code]
+ *	exec_check_permissions:???
+ *	namei:???
+ *	vn_rdwr:???			[anything vn_rdwr can return]
+ *	<ex_imgact>:???			[anything an imgact can return]
+ *	EDEADLK				Process is being terminated
+ */
+static int
+exec_activate_image(struct image_params *imgp)
+{
+	struct nameidata *ndp = NULL;
+	const char *excpath;
+	int error;
+	int resid;
+	int once = 1;   /* save SGUID-ness for interpreted files */
+	int i;
+	int itercount = 0;
+	proc_t p = vfs_context_proc(imgp->ip_vfs_context);
+
+	error = execargs_alloc(imgp);
+	if (error) {
+		goto bad_notrans;
+	}
+
+	error = exec_save_path(imgp, imgp->ip_user_fname, imgp->ip_seg, &excpath);
+	if (error) {
+		goto bad_notrans;
+	}
+
+	/* Use excpath, which contains the copyin-ed exec path */
+	DTRACE_PROC1(exec, uintptr_t, excpath);
+
+	MALLOC(ndp, struct nameidata *, sizeof(*ndp), M_TEMP, M_WAITOK | M_ZERO);
+	if (ndp == NULL) {
+		error = ENOMEM;
+		goto bad_notrans;
+	}
+
+	NDINIT(ndp, LOOKUP, OP_LOOKUP, FOLLOW | LOCKLEAF | AUDITVNPATH1,
+	    UIO_SYSSPACE, CAST_USER_ADDR_T(excpath), imgp->ip_vfs_context);
+
+again:
+	error = namei(ndp);
+	if (error) {
+		goto bad_notrans;
+	}
+	imgp->ip_ndp = ndp;     /* successful namei(); call nameidone() later */
+	imgp->ip_vp = ndp->ni_vp;       /* if set, need to vnode_put() at some point */
+
+	/*
+	 * Before we start the transition from binary A to binary B, make
+	 * sure another thread hasn't started exiting the process.  We grab
+	 * the proc lock to check p_lflag initially, and the transition
+	 * mechanism ensures that the value doesn't change after we release
+	 * the lock.
+	 */
+	proc_lock(p);
+	if (p->p_lflag & P_LEXIT) {
+		error = EDEADLK;
+		proc_unlock(p);
+		goto bad_notrans;
+	}
+	error = proc_transstart(p, 1, 0);
+	proc_unlock(p);
+	if (error) {
+		goto bad_notrans;
+	}
+
+	error = exec_check_permissions(imgp);
+	if (error) {
+		goto bad;
+	}
+
+	/* Copy; avoid invocation of an interpreter overwriting the original */
+	if (once) {
+		once = 0;
+		*imgp->ip_origvattr = *imgp->ip_vattr;
+	}
+
+	error = vn_rdwr(UIO_READ, imgp->ip_vp, imgp->ip_vdata, PAGE_SIZE, 0,
+	    UIO_SYSSPACE, IO_NODELOCKED,
+	    vfs_context_ucred(imgp->ip_vfs_context),
+	    &resid, vfs_context_proc(imgp->ip_vfs_context));
+	if (error) {
+		goto bad;
+	}
+
+	if (resid) {
+		memset(imgp->ip_vdata + (PAGE_SIZE - resid), 0x0, resid);
+	}
+
+encapsulated_binary:
+	/* Limit the number of iterations we will attempt on each binary */
+	if (++itercount > EAI_ITERLIMIT) {
+		error = EBADEXEC;
+		goto bad;
+	}
+	error = -1;
+	for (i = 0; error == -1 && execsw[i].ex_imgact != NULL; i++) {
+		error = (*execsw[i].ex_imgact)(imgp);
+
+		switch (error) {
+		/* case -1: not claimed: continue */
+		case -2:                /* Encapsulated binary, imgp->ip_XXX set for next iteration */
+			goto encapsulated_binary;
+
+		case -3:                /* Interpreter */
+#if CONFIG_MACF
+			/*
+			 * Copy the script label for later use. Note that
+			 * the label can be different when the script is
+			 * actually read by the interpreter.
+			 */
+			if (imgp->ip_scriptlabelp) {
+				mac_vnode_label_free(imgp->ip_scriptlabelp);
+			}
+			imgp->ip_scriptlabelp = mac_vnode_label_alloc();
+			if (imgp->ip_scriptlabelp == NULL) {
+				error = ENOMEM;
+				break;
+			}
+			mac_vnode_label_copy(imgp->ip_vp->v_label,
+			    imgp->ip_scriptlabelp);
+
+			/*
+			 * Take a ref of the script vnode for later use.
+			 */
+			if (imgp->ip_scriptvp) {
+				vnode_put(imgp->ip_scriptvp);
+			}
+			if (vnode_getwithref(imgp->ip_vp) == 0) {
+				imgp->ip_scriptvp = imgp->ip_vp;
+			}
+#endif
+
+			nameidone(ndp);
+
+			vnode_put(imgp->ip_vp);
+			imgp->ip_vp = NULL;     /* already put */
+			imgp->ip_ndp = NULL; /* already nameidone */
+
+			/* Use excpath, which exec_shell_imgact reset to the interpreter */
+			NDINIT(ndp, LOOKUP, OP_LOOKUP, FOLLOW | LOCKLEAF,
+			    UIO_SYSSPACE, CAST_USER_ADDR_T(excpath), imgp->ip_vfs_context);
+
+			proc_transend(p, 0);
+			goto again;
+
+		default:
+			break;
+		}
+	}
+
+	if (error == 0) {
+		if (imgp->ip_flags & IMGPF_INTERPRET && ndp->ni_vp) {
+			AUDIT_ARG(vnpath, ndp->ni_vp, ARG_VNODE2);
+		}
+
+		/*
+		 * Call out to allow 3rd party notification of exec.
+		 * Ignore result of kauth_authorize_fileop call.
+		 */
+		if (kauth_authorize_fileop_has_listeners()) {
+			kauth_authorize_fileop(vfs_context_ucred(imgp->ip_vfs_context),
+			    KAUTH_FILEOP_EXEC,
+			    (uintptr_t)ndp->ni_vp, 0);
+		}
+	}
+bad:
+	proc_transend(p, 0);
+
+bad_notrans:
+	if (imgp->ip_strings) {
+		execargs_free(imgp);
+	}
+	if (imgp->ip_ndp) {
+		nameidone(imgp->ip_ndp);
+	}
+	if (ndp) {
+		FREE(ndp, M_TEMP);
+	}
+
+	return error;
+}
+
+/*
+ * exec_validate_spawnattr_policy
+ *
+ * Description: Validates the entitlements required to set the apptype.
+ *
+ * Parameters:  int psa_apptype         posix spawn attribute apptype
+ *
+ * Returns:     0                       Success
+ *              EPERM                   Failure
+ */
+static errno_t
+exec_validate_spawnattr_policy(int psa_apptype)
+{
+	if ((psa_apptype & POSIX_SPAWN_PROC_TYPE_MASK) != 0) {
+		int proctype = psa_apptype & POSIX_SPAWN_PROC_TYPE_MASK;
+		if (proctype == POSIX_SPAWN_PROC_TYPE_DRIVER) {
+			if (!IOTaskHasEntitlement(current_task(), POSIX_SPAWN_ENTITLEMENT_DRIVER)) {
+				return EPERM;
+			}
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * exec_handle_spawnattr_policy
+ *
+ * Description: Decode and apply the posix_spawn apptype, qos clamp, and watchport ports to the task.
+ *
+ * Parameters:  proc_t p                process to apply attributes to
+ *              int psa_apptype         posix spawn attribute apptype
+ *
+ * Returns:     0                       Success
+ */
+static errno_t
+exec_handle_spawnattr_policy(proc_t p, thread_t thread, int psa_apptype, uint64_t psa_qos_clamp,
+    uint64_t psa_darwin_role, struct exec_port_actions *port_actions)
+{
+	int apptype     = TASK_APPTYPE_NONE;
+	int qos_clamp   = THREAD_QOS_UNSPECIFIED;
+	int role        = TASK_UNSPECIFIED;
+
+	if ((psa_apptype & POSIX_SPAWN_PROC_TYPE_MASK) != 0) {
+		int proctype = psa_apptype & POSIX_SPAWN_PROC_TYPE_MASK;
+
+		switch (proctype) {
+		case POSIX_SPAWN_PROC_TYPE_DAEMON_INTERACTIVE:
+			apptype = TASK_APPTYPE_DAEMON_INTERACTIVE;
+			break;
+		case POSIX_SPAWN_PROC_TYPE_DAEMON_STANDARD:
+			apptype = TASK_APPTYPE_DAEMON_STANDARD;
+			break;
+		case POSIX_SPAWN_PROC_TYPE_DAEMON_ADAPTIVE:
+			apptype = TASK_APPTYPE_DAEMON_ADAPTIVE;
+			break;
+		case POSIX_SPAWN_PROC_TYPE_DAEMON_BACKGROUND:
+			apptype = TASK_APPTYPE_DAEMON_BACKGROUND;
+			break;
+		case POSIX_SPAWN_PROC_TYPE_APP_DEFAULT:
+			apptype = TASK_APPTYPE_APP_DEFAULT;
+			break;
+#if !CONFIG_EMBEDDED
+		case POSIX_SPAWN_PROC_TYPE_APP_TAL:
+			apptype = TASK_APPTYPE_APP_TAL;
+			break;
+#endif /* !CONFIG_EMBEDDED */
+		case POSIX_SPAWN_PROC_TYPE_DRIVER:
+			apptype = TASK_APPTYPE_DRIVER;
+			break;
+		default:
+			apptype = TASK_APPTYPE_NONE;
+			/* TODO: Should an invalid value here fail the spawn? */
+			break;
+		}
+	}
+
+	if (psa_qos_clamp != POSIX_SPAWN_PROC_CLAMP_NONE) {
+		switch (psa_qos_clamp) {
+		case POSIX_SPAWN_PROC_CLAMP_UTILITY:
+			qos_clamp = THREAD_QOS_UTILITY;
+			break;
+		case POSIX_SPAWN_PROC_CLAMP_BACKGROUND:
+			qos_clamp = THREAD_QOS_BACKGROUND;
+			break;
+		case POSIX_SPAWN_PROC_CLAMP_MAINTENANCE:
+			qos_clamp = THREAD_QOS_MAINTENANCE;
+			break;
+		default:
+			qos_clamp = THREAD_QOS_UNSPECIFIED;
+			/* TODO: Should an invalid value here fail the spawn? */
+			break;
+		}
+	}
+
+	if (psa_darwin_role != PRIO_DARWIN_ROLE_DEFAULT) {
+		proc_darwin_role_to_task_role(psa_darwin_role, &role);
+	}
+
+	if (apptype != TASK_APPTYPE_NONE ||
+	    qos_clamp != THREAD_QOS_UNSPECIFIED ||
+	    role != TASK_UNSPECIFIED ||
+	    port_actions->portwatch_count) {
+		proc_set_task_spawnpolicy(p->task, thread, apptype, qos_clamp, role,
+		    port_actions->portwatch_array, port_actions->portwatch_count);
+	}
+
+	if (port_actions->registered_count) {
+		if (mach_ports_register(p->task, port_actions->registered_array,
+		    port_actions->registered_count)) {
+			return EINVAL;
+		}
+		/* mach_ports_register() consumed the array */
+		port_actions->registered_array = NULL;
+		port_actions->registered_count = 0;
+	}
+
+	return 0;
+}
+
+static void
+exec_port_actions_destroy(struct exec_port_actions *port_actions)
+{
+	if (port_actions->portwatch_array) {
+		for (uint32_t i = 0; i < port_actions->portwatch_count; i++) {
+			ipc_port_t port = NULL;
+			if ((port = port_actions->portwatch_array[i]) != NULL) {
+				ipc_port_release_send(port);
+			}
+		}
+		kfree(port_actions->portwatch_array,
+		    port_actions->portwatch_count * sizeof(ipc_port_t *));
+	}
+
+	if (port_actions->registered_array) {
+		for (uint32_t i = 0; i < port_actions->registered_count; i++) {
+			ipc_port_t port = NULL;
+			if ((port = port_actions->registered_array[i]) != NULL) {
+				ipc_port_release_send(port);
+			}
+		}
+		kfree(port_actions->registered_array,
+		    port_actions->registered_count * sizeof(ipc_port_t *));
+	}
+}
+
+/*
+ * exec_handle_port_actions
+ *
+ * Description:	Go through the _posix_port_actions_t contents,
+ *              calling task_set_special_port, task_set_exception_ports
+ *              and/or audit_session_spawnjoin for the current task.
+ *
+ * Parameters:	struct image_params *	Image parameter block
+ *
+ * Returns:	0			Success
+ *              EINVAL			Failure
+ *              ENOTSUP			Illegal posix_spawn attr flag was set
+ */
+static errno_t
+exec_handle_port_actions(struct image_params *imgp,
+    struct exec_port_actions *actions)
+{
+	_posix_spawn_port_actions_t pacts = imgp->ip_px_spa;
+#if CONFIG_AUDIT
+	proc_t p = vfs_context_proc(imgp->ip_vfs_context);
+#endif
+	_ps_port_action_t *act = NULL;
+	task_t task = get_threadtask(imgp->ip_new_thread);
+	ipc_port_t port = NULL;
+	errno_t ret = 0;
+	int i, portwatch_i = 0, registered_i = 0;
+	kern_return_t kr;
+	boolean_t task_has_watchport_boost = task_has_watchports(current_task());
+	boolean_t in_exec = (imgp->ip_flags & IMGPF_EXEC);
+
+	for (i = 0; i < pacts->pspa_count; i++) {
+		act = &pacts->pspa_actions[i];
+
+		switch (act->port_type) {
+		case PSPA_SPECIAL:
+		case PSPA_EXCEPTION:
+#if CONFIG_AUDIT
+		case PSPA_AU_SESSION:
+#endif
+			break;
+		case PSPA_IMP_WATCHPORTS:
+			if (++actions->portwatch_count > TASK_MAX_WATCHPORT_COUNT) {
+				ret = EINVAL;
+				goto done;
+			}
+			break;
+		case PSPA_REGISTERED_PORTS:
+			if (++actions->registered_count > TASK_PORT_REGISTER_MAX) {
+				ret = EINVAL;
+				goto done;
+			}
+			break;
+		default:
+			ret = EINVAL;
+			goto done;
+		}
+	}
+
+	if (actions->portwatch_count) {
+		if (in_exec && task_has_watchport_boost) {
+			ret = EINVAL;
+			goto done;
+		}
+		actions->portwatch_array =
+		    kalloc(sizeof(ipc_port_t *) * actions->portwatch_count);
+		if (actions->portwatch_array == NULL) {
+			ret = ENOMEM;
+			goto done;
+		}
+		bzero(actions->portwatch_array,
+		    sizeof(ipc_port_t *) * actions->portwatch_count);
+	}
+
+	if (actions->registered_count) {
+		actions->registered_array =
+		    kalloc(sizeof(ipc_port_t *) * actions->registered_count);
+		if (actions->registered_array == NULL) {
+			ret = ENOMEM;
+			goto done;
+		}
+		bzero(actions->registered_array,
+		    sizeof(ipc_port_t *) * actions->registered_count);
+	}
+
+	for (i = 0; i < pacts->pspa_count; i++) {
+		act = &pacts->pspa_actions[i];
+
+		if (MACH_PORT_VALID(act->new_port)) {
+			kr = ipc_object_copyin(get_task_ipcspace(current_task()),
+			    act->new_port, MACH_MSG_TYPE_COPY_SEND,
+			    (ipc_object_t *) &port, 0, NULL, IPC_KMSG_FLAGS_ALLOW_IMMOVABLE_SEND);
+
+			if (kr != KERN_SUCCESS) {
+				ret = EINVAL;
+				goto done;
+			}
+		} else {
+			/* it's NULL or DEAD */
+			port = CAST_MACH_NAME_TO_PORT(act->new_port);
+		}
+
+		switch (act->port_type) {
+		case PSPA_SPECIAL:
+			kr = task_set_special_port(task, act->which, port);
+
+			if (kr != KERN_SUCCESS) {
+				ret = EINVAL;
+			}
+			break;
+
+		case PSPA_EXCEPTION:
+			kr = task_set_exception_ports(task, act->mask, port,
+			    act->behavior, act->flavor);
+			if (kr != KERN_SUCCESS) {
+				ret = EINVAL;
+			}
+			break;
+#if CONFIG_AUDIT
+		case PSPA_AU_SESSION:
+			ret = audit_session_spawnjoin(p, task, port);
+			if (ret) {
+				/* audit_session_spawnjoin() has already dropped the reference in case of error. */
+				goto done;
+			}
+
+			break;
+#endif
+		case PSPA_IMP_WATCHPORTS:
+			if (actions->portwatch_array) {
+				/* hold on to this till end of spawn */
+				actions->portwatch_array[portwatch_i++] = port;
+			} else {
+				ipc_port_release_send(port);
+			}
+			break;
+		case PSPA_REGISTERED_PORTS:
+			/* hold on to this till end of spawn */
+			actions->registered_array[registered_i++] = port;
+			break;
+		default:
+			ret = EINVAL;
+			break;
+		}
+
+		if (ret) {
+			/* action failed, so release port resources */
+			ipc_port_release_send(port);
+			break;
+		}
+	}
+
+done:
+	if (0 != ret) {
+		DTRACE_PROC1(spawn__port__failure, mach_port_name_t, act->new_port);
+	}
+	return ret;
+}
+
+/*
+ * exec_handle_file_actions
+ *
+ * Description:	Go through the _posix_file_actions_t contents applying the
+ *		open, close, and dup2 operations to the open file table for
+ *		the current process.
+ *
+ * Parameters:	struct image_params *	Image parameter block
+ *
+ * Returns:	0			Success
+ *		???
+ *
+ * Note:	Actions are applied in the order specified, with the credential
+ *		of the parent process.  This is done to permit the parent
+ *		process to utilize POSIX_SPAWN_RESETIDS to drop privilege in
+ *		the child following operations the child may in fact not be
+ *		normally permitted to perform.
+ */
+static int
+exec_handle_file_actions(struct image_params *imgp, short psa_flags)
+{
+	int error = 0;
+	int action;
+	proc_t p = vfs_context_proc(imgp->ip_vfs_context);
+	_posix_spawn_file_actions_t px_sfap = imgp->ip_px_sfa;
+	int ival[2];            /* dummy retval for system calls) */
+
+	for (action = 0; action < px_sfap->psfa_act_count; action++) {
+		_psfa_action_t *psfa = &px_sfap->psfa_act_acts[action];
+
+		switch (psfa->psfaa_type) {
+		case PSFA_OPEN: {
+			/*
+			 * Open is different, in that it requires the use of
+			 * a path argument, which is normally copied in from
+			 * user space; because of this, we have to support an
+			 * open from kernel space that passes an address space
+			 * context of UIO_SYSSPACE, and casts the address
+			 * argument to a user_addr_t.
+			 */
+			char *bufp = NULL;
+			struct vnode_attr *vap;
+			struct nameidata *ndp;
+			int mode = psfa->psfaa_openargs.psfao_mode;
+			struct dup2_args dup2a;
+			struct close_nocancel_args ca;
+			int origfd;
+
+			MALLOC(bufp, char *, sizeof(*vap) + sizeof(*ndp), M_TEMP, M_WAITOK | M_ZERO);
+			if (bufp == NULL) {
+				error = ENOMEM;
+				break;
+			}
+
+			vap = (struct vnode_attr *) bufp;
+			ndp = (struct nameidata *) (bufp + sizeof(*vap));
+
+			VATTR_INIT(vap);
+			/* Mask off all but regular access permissions */
+			mode = ((mode & ~p->p_fd->fd_cmask) & ALLPERMS) & ~S_ISTXT;
+			VATTR_SET(vap, va_mode, mode & ACCESSPERMS);
+
+			NDINIT(ndp, LOOKUP, OP_OPEN, FOLLOW | AUDITVNPATH1, UIO_SYSSPACE,
+			    CAST_USER_ADDR_T(psfa->psfaa_openargs.psfao_path),
+			    imgp->ip_vfs_context);
+
+			error = open1(imgp->ip_vfs_context,
+			    ndp,
+			    psfa->psfaa_openargs.psfao_oflag,
+			    vap,
+			    fileproc_alloc_init, NULL,
+			    ival);
+
+			FREE(bufp, M_TEMP);
+
+			/*
+			 * If there's an error, or we get the right fd by
+			 * accident, then drop out here.  This is easier than
+			 * reworking all the open code to preallocate fd
+			 * slots, and internally taking one as an argument.
+			 */
+			if (error || ival[0] == psfa->psfaa_filedes) {
+				break;
+			}
+
+			origfd = ival[0];
+			/*
+			 * If we didn't fall out from an error, we ended up
+			 * with the wrong fd; so now we've got to try to dup2
+			 * it to the right one.
+			 */
+			dup2a.from = origfd;
+			dup2a.to = psfa->psfaa_filedes;
+
+			/*
+			 * The dup2() system call implementation sets
+			 * ival to newfd in the success case, but we
+			 * can ignore that, since if we didn't get the
+			 * fd we wanted, the error will stop us.
+			 */
+			error = dup2(p, &dup2a, ival);
+			if (error) {
+				break;
+			}
+
+			/*
+			 * Finally, close the original fd.
+			 */
+			ca.fd = origfd;
+
+			error = close_nocancel(p, &ca, ival);
+		}
+		break;
+
+		case PSFA_DUP2: {
+			struct dup2_args dup2a;
+
+			dup2a.from = psfa->psfaa_filedes;
+			dup2a.to = psfa->psfaa_dup2args.psfad_newfiledes;
+
+			/*
+			 * The dup2() system call implementation sets
+			 * ival to newfd in the success case, but we
+			 * can ignore that, since if we didn't get the
+			 * fd we wanted, the error will stop us.
+			 */
+			error = dup2(p, &dup2a, ival);
+		}
+		break;
+
+		case PSFA_FILEPORT_DUP2: {
+			ipc_port_t port;
+			kern_return_t kr;
+			struct dup2_args dup2a;
+			struct close_nocancel_args ca;
+
+			if (!MACH_PORT_VALID(psfa->psfaa_fileport)) {
+				error = EINVAL;
+				break;
+			}
+
+			kr = ipc_object_copyin(get_task_ipcspace(current_task()),
+			    psfa->psfaa_fileport, MACH_MSG_TYPE_COPY_SEND,
+			    (ipc_object_t *) &port, 0, NULL, IPC_KMSG_FLAGS_ALLOW_IMMOVABLE_SEND);
+
+			if (kr != KERN_SUCCESS) {
+				error = EINVAL;
+				break;
+			}
+
+			error = fileport_makefd_internal(p, port, 0, ival);
+
+			if (IPC_PORT_NULL != port) {
+				ipc_port_release_send(port);
+			}
+
+			if (error || ival[0] == psfa->psfaa_dup2args.psfad_newfiledes) {
+				break;
+			}
+
+			dup2a.from = ca.fd = ival[0];
+			dup2a.to = psfa->psfaa_dup2args.psfad_newfiledes;
+			error = dup2(p, &dup2a, ival);
+			if (error) {
+				break;
+			}
+
+			error = close_nocancel(p, &ca, ival);
+		}
+		break;
+
+		case PSFA_CLOSE: {
+			struct close_nocancel_args ca;
+
+			ca.fd = psfa->psfaa_filedes;
+
+			error = close_nocancel(p, &ca, ival);
+		}
+		break;
+
+		case PSFA_INHERIT: {
+			struct fcntl_nocancel_args fcntla;
+
+			/*
+			 * Check to see if the descriptor exists, and
+			 * ensure it's -not- marked as close-on-exec.
+			 *
+			 * Attempting to "inherit" a guarded fd will
+			 * result in a error.
+			 */
+			fcntla.fd = psfa->psfaa_filedes;
+			fcntla.cmd = F_GETFD;
+			if ((error = fcntl_nocancel(p, &fcntla, ival)) != 0) {
+				break;
+			}
+
+			if ((ival[0] & FD_CLOEXEC) == FD_CLOEXEC) {
+				fcntla.fd = psfa->psfaa_filedes;
+				fcntla.cmd = F_SETFD;
+				fcntla.arg = ival[0] & ~FD_CLOEXEC;
+				error = fcntl_nocancel(p, &fcntla, ival);
+			}
+		}
+		break;
+
+		case PSFA_CHDIR: {
+			/*
+			 * Chdir is different, in that it requires the use of
+			 * a path argument, which is normally copied in from
+			 * user space; because of this, we have to support a
+			 * chdir from kernel space that passes an address space
+			 * context of UIO_SYSSPACE, and casts the address
+			 * argument to a user_addr_t.
+			 */
+			struct nameidata nd;
+
+			NDINIT(&nd, LOOKUP, OP_CHDIR, FOLLOW | AUDITVNPATH1, UIO_SYSSPACE,
+			    CAST_USER_ADDR_T(psfa->psfaa_chdirargs.psfac_path),
+			    imgp->ip_vfs_context);
+
+			error = chdir_internal(p, imgp->ip_vfs_context, &nd, 0);
+		}
+		break;
+
+		case PSFA_FCHDIR: {
+			struct fchdir_args fchdira;
+
+			fchdira.fd = psfa->psfaa_filedes;
+
+			error = fchdir(p, &fchdira, ival);
+		}
+		break;
+
+		default:
+			error = EINVAL;
+			break;
+		}
+
+		/* All file actions failures are considered fatal, per POSIX */
+
+		if (error) {
+			if (PSFA_OPEN == psfa->psfaa_type) {
+				DTRACE_PROC1(spawn__open__failure, uintptr_t,
+				    psfa->psfaa_openargs.psfao_path);
+			} else {
+				DTRACE_PROC1(spawn__fd__failure, int, psfa->psfaa_filedes);
+			}
+			break;
+		}
+	}
+
+	if (error != 0 || (psa_flags & POSIX_SPAWN_CLOEXEC_DEFAULT) == 0) {
+		return error;
+	}
+
+	/*
+	 * If POSIX_SPAWN_CLOEXEC_DEFAULT is set, behave (during
+	 * this spawn only) as if "close on exec" is the default
+	 * disposition of all pre-existing file descriptors.  In this case,
+	 * the list of file descriptors mentioned in the file actions
+	 * are the only ones that can be inherited, so mark them now.
+	 *
+	 * The actual closing part comes later, in fdexec().
+	 */
+	proc_fdlock(p);
+	for (action = 0; action < px_sfap->psfa_act_count; action++) {
+		_psfa_action_t *psfa = &px_sfap->psfa_act_acts[action];
+		int fd = psfa->psfaa_filedes;
+
+		switch (psfa->psfaa_type) {
+		case PSFA_DUP2:
+		case PSFA_FILEPORT_DUP2:
+			fd = psfa->psfaa_dup2args.psfad_newfiledes;
+		/*FALLTHROUGH*/
+		case PSFA_OPEN:
+		case PSFA_INHERIT:
+			*fdflags(p, fd) |= UF_INHERIT;
+			break;
+
+		case PSFA_CLOSE:
+		case PSFA_CHDIR:
+		case PSFA_FCHDIR:
+			/*
+			 * Although PSFA_FCHDIR does have a file descriptor, it is not
+			 * *creating* one, thus we do not automatically mark it for
+			 * inheritance under POSIX_SPAWN_CLOEXEC_DEFAULT. A client that
+			 * wishes it to be inherited should use the PSFA_INHERIT action
+			 * explicitly.
+			 */
+			break;
+		}
+	}
+	proc_fdunlock(p);
+
+	return 0;
+}
+
+#if CONFIG_MACF
+/*
+ * exec_spawnattr_getmacpolicyinfo
+ */
+void *
+exec_spawnattr_getmacpolicyinfo(const void *macextensions, const char *policyname, size_t *lenp)
+{
+	const struct _posix_spawn_mac_policy_extensions *psmx = macextensions;
+	int i;
+
+	if (psmx == NULL) {
+		return NULL;
+	}
+
+	for (i = 0; i < psmx->psmx_count; i++) {
+		const _ps_mac_policy_extension_t *extension = &psmx->psmx_extensions[i];
+		if (strncmp(extension->policyname, policyname, sizeof(extension->policyname)) == 0) {
+			if (lenp != NULL) {
+				*lenp = extension->datalen;
+			}
+			return extension->datap;
+		}
+	}
+
+	if (lenp != NULL) {
+		*lenp = 0;
+	}
+	return NULL;
+}
+
+static int
+spawn_copyin_macpolicyinfo(const struct user__posix_spawn_args_desc *px_args, _posix_spawn_mac_policy_extensions_t *psmxp)
+{
+	_posix_spawn_mac_policy_extensions_t psmx = NULL;
+	int error = 0;
+	int copycnt = 0;
+	int i = 0;
+
+	*psmxp = NULL;
+
+	if (px_args->mac_extensions_size < PS_MAC_EXTENSIONS_SIZE(1) ||
+	    px_args->mac_extensions_size > PAGE_SIZE) {
+		error = EINVAL;
+		goto bad;
+	}
+
+	MALLOC(psmx, _posix_spawn_mac_policy_extensions_t, px_args->mac_extensions_size, M_TEMP, M_WAITOK);
+	if ((error = copyin(px_args->mac_extensions, psmx, px_args->mac_extensions_size)) != 0) {
+		goto bad;
+	}
+
+	size_t extsize = PS_MAC_EXTENSIONS_SIZE(psmx->psmx_count);
+	if (extsize == 0 || extsize > px_args->mac_extensions_size) {
+		error = EINVAL;
+		goto bad;
+	}
+
+	for (i = 0; i < psmx->psmx_count; i++) {
+		_ps_mac_policy_extension_t *extension = &psmx->psmx_extensions[i];
+		if (extension->datalen == 0 || extension->datalen > PAGE_SIZE) {
+			error = EINVAL;
+			goto bad;
+		}
+	}
+
+	for (copycnt = 0; copycnt < psmx->psmx_count; copycnt++) {
+		_ps_mac_policy_extension_t *extension = &psmx->psmx_extensions[copycnt];
+		void *data = NULL;
+
+		MALLOC(data, void *, extension->datalen, M_TEMP, M_WAITOK);
+		if ((error = copyin(extension->data, data, extension->datalen)) != 0) {
+			FREE(data, M_TEMP);
+			goto bad;
+		}
+		extension->datap = data;
+	}
+
+	*psmxp = psmx;
+	return 0;
+
+bad:
+	if (psmx != NULL) {
+		for (i = 0; i < copycnt; i++) {
+			FREE(psmx->psmx_extensions[i].datap, M_TEMP);
+		}
+		FREE(psmx, M_TEMP);
+	}
+	return error;
+}
+
+static void
+spawn_free_macpolicyinfo(_posix_spawn_mac_policy_extensions_t psmx)
+{
+	int i;
+
+	if (psmx == NULL) {
+		return;
+	}
+	for (i = 0; i < psmx->psmx_count; i++) {
+		FREE(psmx->psmx_extensions[i].datap, M_TEMP);
+	}
+	FREE(psmx, M_TEMP);
+}
+#endif /* CONFIG_MACF */
+
+#if CONFIG_COALITIONS
+static inline void
+spawn_coalitions_release_all(coalition_t coal[COALITION_NUM_TYPES])
+{
+	for (int c = 0; c < COALITION_NUM_TYPES; c++) {
+		if (coal[c]) {
+			coalition_remove_active(coal[c]);
+			coalition_release(coal[c]);
+		}
+	}
+}
+#endif
+
+#if CONFIG_PERSONAS
+static int
+spawn_validate_persona(struct _posix_spawn_persona_info *px_persona)
+{
+	int error = 0;
+	struct persona *persona = NULL;
+	int verify = px_persona->pspi_flags & POSIX_SPAWN_PERSONA_FLAGS_VERIFY;
+
+	if (!IOTaskHasEntitlement(current_task(), PERSONA_MGMT_ENTITLEMENT)) {
+		return EPERM;
+	}
+
+	if (px_persona->pspi_flags & POSIX_SPAWN_PERSONA_GROUPS) {
+		if (px_persona->pspi_ngroups > NGROUPS_MAX) {
+			return EINVAL;
+		}
+	}
+
+	persona = persona_lookup(px_persona->pspi_id);
+	if (!persona) {
+		error = ESRCH;
+		goto out;
+	}
+
+	if (verify) {
+		if (px_persona->pspi_flags & POSIX_SPAWN_PERSONA_UID) {
+			if (px_persona->pspi_uid != persona_get_uid(persona)) {
+				error = EINVAL;
+				goto out;
+			}
+		}
+		if (px_persona->pspi_flags & POSIX_SPAWN_PERSONA_GID) {
+			if (px_persona->pspi_gid != persona_get_gid(persona)) {
+				error = EINVAL;
+				goto out;
+			}
+		}
+		if (px_persona->pspi_flags & POSIX_SPAWN_PERSONA_GROUPS) {
+			unsigned ngroups = 0;
+			gid_t groups[NGROUPS_MAX];
+
+			if (persona_get_groups(persona, &ngroups, groups,
+			    px_persona->pspi_ngroups) != 0) {
+				error = EINVAL;
+				goto out;
+			}
+			if (ngroups != px_persona->pspi_ngroups) {
+				error = EINVAL;
+				goto out;
+			}
+			while (ngroups--) {
+				if (px_persona->pspi_groups[ngroups] != groups[ngroups]) {
+					error = EINVAL;
+					goto out;
+				}
+			}
+			if (px_persona->pspi_gmuid != persona_get_gmuid(persona)) {
+				error = EINVAL;
+				goto out;
+			}
+		}
+	}
+
+out:
+	if (persona) {
+		persona_put(persona);
+	}
+
+	return error;
+}
+
+static int
+spawn_persona_adopt(proc_t p, struct _posix_spawn_persona_info *px_persona)
+{
+	int ret;
+	kauth_cred_t cred;
+	struct persona *persona = NULL;
+	int override = !!(px_persona->pspi_flags & POSIX_SPAWN_PERSONA_FLAGS_OVERRIDE);
+
+	if (!override) {
+		return persona_proc_adopt_id(p, px_persona->pspi_id, NULL);
+	}
+
+	/*
+	 * we want to spawn into the given persona, but we want to override
+	 * the kauth with a different UID/GID combo
+	 */
+	persona = persona_lookup(px_persona->pspi_id);
+	if (!persona) {
+		return ESRCH;
+	}
+
+	cred = persona_get_cred(persona);
+	if (!cred) {
+		ret = EINVAL;
+		goto out;
+	}
+
+	if (px_persona->pspi_flags & POSIX_SPAWN_PERSONA_UID) {
+		cred = kauth_cred_setresuid(cred,
+		    px_persona->pspi_uid,
+		    px_persona->pspi_uid,
+		    px_persona->pspi_uid,
+		    KAUTH_UID_NONE);
+	}
+
+	if (px_persona->pspi_flags & POSIX_SPAWN_PERSONA_GID) {
+		cred = kauth_cred_setresgid(cred,
+		    px_persona->pspi_gid,
+		    px_persona->pspi_gid,
+		    px_persona->pspi_gid);
+	}
+
+	if (px_persona->pspi_flags & POSIX_SPAWN_PERSONA_GROUPS) {
+		cred = kauth_cred_setgroups(cred,
+		    px_persona->pspi_groups,
+		    px_persona->pspi_ngroups,
+		    px_persona->pspi_gmuid);
+	}
+
+	ret = persona_proc_adopt(p, persona, cred);
+
+out:
+	persona_put(persona);
+	return ret;
+}
+#endif
+
+#if __arm64__
+extern int legacy_footprint_entitlement_mode;
+static inline void
+proc_legacy_footprint_entitled(proc_t p, task_t task, const char *caller)
+{
+#pragma unused(p, caller)
+	boolean_t legacy_footprint_entitled;
+
+	switch (legacy_footprint_entitlement_mode) {
+	case LEGACY_FOOTPRINT_ENTITLEMENT_IGNORE:
+		/* the entitlement is ignored */
+		break;
+	case LEGACY_FOOTPRINT_ENTITLEMENT_IOS11_ACCT:
+		/* the entitlement grants iOS11 legacy accounting */
+		legacy_footprint_entitled = IOTaskHasEntitlement(task,
+		    "com.apple.private.memory.legacy_footprint");
+		if (legacy_footprint_entitled) {
+			task_set_legacy_footprint(task);
+		}
+		break;
+	case LEGACY_FOOTPRINT_ENTITLEMENT_LIMIT_INCREASE:
+		/* the entitlement grants a footprint limit increase */
+		legacy_footprint_entitled = IOTaskHasEntitlement(task,
+		    "com.apple.private.memory.legacy_footprint");
+		if (legacy_footprint_entitled) {
+			task_set_extra_footprint_limit(task);
+		}
+		break;
+	default:
+		break;
+	}
+}
+#endif /* __arm64__ */
+
+/*
+ * Apply a modification on the proc's kauth cred until it converges.
+ *
+ * `update` consumes its argument to return a new kauth cred.
+ */
+static void
+apply_kauth_cred_update(proc_t p,
+    kauth_cred_t (^update)(kauth_cred_t orig_cred))
+{
+	kauth_cred_t my_cred, my_new_cred;
+
+	my_cred = kauth_cred_proc_ref(p);
+	for (;;) {
+		my_new_cred = update(my_cred);
+		if (my_cred == my_new_cred) {
+			kauth_cred_unref(&my_new_cred);
+			break;
+		}
+
+		/* try update cred on proc */
+		proc_ucred_lock(p);
+
+		if (p->p_ucred == my_cred) {
+			/* base pointer didn't change, donate our ref */
+			p->p_ucred = my_new_cred;
+			PROC_UPDATE_CREDS_ONPROC(p);
+			proc_ucred_unlock(p);
+
+			/* drop p->p_ucred reference */
+			kauth_cred_unref(&my_cred);
+			break;
+		}
+
+		/* base pointer changed, retry */
+		my_cred = p->p_ucred;
+		kauth_cred_ref(my_cred);
+		proc_ucred_unlock(p);
+
+		kauth_cred_unref(&my_new_cred);
+	}
+}
+
+static int
+spawn_posix_cred_adopt(proc_t p,
+    struct _posix_spawn_posix_cred_info *px_pcred_info)
+{
+	int error = 0;
+
+	if (px_pcred_info->pspci_flags & POSIX_SPAWN_POSIX_CRED_GID) {
+		struct setgid_args args = {
+			.gid = px_pcred_info->pspci_gid,
+		};
+		error = setgid(p, &args, NULL);
+		if (error) {
+			return error;
+		}
+	}
+
+	if (px_pcred_info->pspci_flags & POSIX_SPAWN_POSIX_CRED_GROUPS) {
+		error = setgroups_internal(p,
+		    px_pcred_info->pspci_ngroups,
+		    px_pcred_info->pspci_groups,
+		    px_pcred_info->pspci_gmuid);
+		if (error) {
+			return error;
+		}
+	}
+
+	if (px_pcred_info->pspci_flags & POSIX_SPAWN_POSIX_CRED_UID) {
+		struct setuid_args args = {
+			.uid = px_pcred_info->pspci_uid,
+		};
+		error = setuid(p, &args, NULL);
+		if (error) {
+			return error;
+		}
+	}
+	return 0;
+}
+
+/*
+ * posix_spawn
+ *
+ * Parameters:	uap->pid		Pointer to pid return area
+ *		uap->fname		File name to exec
+ *		uap->argp		Argument list
+ *		uap->envp		Environment list
+ *
+ * Returns:	0			Success
+ *		EINVAL			Invalid argument
+ *		ENOTSUP			Not supported
+ *		ENOEXEC			Executable file format error
+ *	exec_activate_image:EINVAL	Invalid argument
+ *	exec_activate_image:EACCES	Permission denied
+ *	exec_activate_image:EINTR	Interrupted function
+ *	exec_activate_image:ENOMEM	Not enough space
+ *	exec_activate_image:EFAULT	Bad address
+ *	exec_activate_image:ENAMETOOLONG	Filename too long
+ *	exec_activate_image:ENOEXEC	Executable file format error
+ *	exec_activate_image:ETXTBSY	Text file busy [misuse of error code]
+ *	exec_activate_image:EAUTH	Image decryption failed
+ *	exec_activate_image:EBADEXEC	The executable is corrupt/unknown
+ *	exec_activate_image:???
+ *	mac_execve_enter:???
+ *
+ * TODO:	Expect to need __mac_posix_spawn() at some point...
+ *		Handle posix_spawnattr_t
+ *		Handle posix_spawn_file_actions_t
+ */
+int
+posix_spawn(proc_t ap, struct posix_spawn_args *uap, int32_t *retval)
+{
+	proc_t p = ap;          /* quiet bogus GCC vfork() warning */
+	user_addr_t pid = uap->pid;
+	int ival[2];            /* dummy retval for setpgid() */
+	char *bufp = NULL;
+	struct image_params *imgp;
+	struct vnode_attr *vap;
+	struct vnode_attr *origvap;
+	struct uthread  *uthread = 0;   /* compiler complains if not set to 0*/
+	int error, sig;
+	int is_64 = IS_64BIT_PROCESS(p);
+	struct vfs_context context;
+	struct user__posix_spawn_args_desc px_args;
+	struct _posix_spawnattr px_sa;
+	_posix_spawn_file_actions_t px_sfap = NULL;
+	_posix_spawn_port_actions_t px_spap = NULL;
+	struct __kern_sigaction vec;
+	boolean_t spawn_no_exec = FALSE;
+	boolean_t proc_transit_set = TRUE;
+	boolean_t exec_done = FALSE;
+	struct exec_port_actions port_actions = { };
+	vm_size_t px_sa_offset = offsetof(struct _posix_spawnattr, psa_ports);
+	task_t old_task = current_task();
+	task_t new_task = NULL;
+	boolean_t should_release_proc_ref = FALSE;
+	void *inherit = NULL;
+#if CONFIG_PERSONAS
+	struct _posix_spawn_persona_info *px_persona = NULL;
+#endif
+	struct _posix_spawn_posix_cred_info *px_pcred_info = NULL;
+
+	/*
+	 * Allocate a big chunk for locals instead of using stack since these
+	 * structures are pretty big.
+	 */
+	MALLOC(bufp, char *, (sizeof(*imgp) + sizeof(*vap) + sizeof(*origvap)), M_TEMP, M_WAITOK | M_ZERO);
+	imgp = (struct image_params *) bufp;
+	if (bufp == NULL) {
+		error = ENOMEM;
+		goto bad;
+	}
+	vap = (struct vnode_attr *) (bufp + sizeof(*imgp));
+	origvap = (struct vnode_attr *) (bufp + sizeof(*imgp) + sizeof(*vap));
+
+	/* Initialize the common data in the image_params structure */
+	imgp->ip_user_fname = uap->path;
+	imgp->ip_user_argv = uap->argv;
+	imgp->ip_user_envv = uap->envp;
+	imgp->ip_vattr = vap;
+	imgp->ip_origvattr = origvap;
+	imgp->ip_vfs_context = &context;
+	imgp->ip_flags = (is_64 ? IMGPF_WAS_64BIT_ADDR : IMGPF_NONE);
+	imgp->ip_seg = (is_64 ? UIO_USERSPACE64 : UIO_USERSPACE32);
+	imgp->ip_mac_return = 0;
+	imgp->ip_px_persona = NULL;
+	imgp->ip_px_pcred_info = NULL;
+	imgp->ip_cs_error = OS_REASON_NULL;
+	imgp->ip_simulator_binary = IMGPF_SB_DEFAULT;
+
+	if (uap->adesc != USER_ADDR_NULL) {
+		if (is_64) {
+			error = copyin(uap->adesc, &px_args, sizeof(px_args));
+		} else {
+			struct user32__posix_spawn_args_desc px_args32;
+
+			error = copyin(uap->adesc, &px_args32, sizeof(px_args32));
+
+			/*
+			 * Convert arguments descriptor from external 32 bit
+			 * representation to internal 64 bit representation
+			 */
+			px_args.attr_size = px_args32.attr_size;
+			px_args.attrp = CAST_USER_ADDR_T(px_args32.attrp);
+			px_args.file_actions_size = px_args32.file_actions_size;
+			px_args.file_actions = CAST_USER_ADDR_T(px_args32.file_actions);
+			px_args.port_actions_size = px_args32.port_actions_size;
+			px_args.port_actions = CAST_USER_ADDR_T(px_args32.port_actions);
+			px_args.mac_extensions_size = px_args32.mac_extensions_size;
+			px_args.mac_extensions = CAST_USER_ADDR_T(px_args32.mac_extensions);
+			px_args.coal_info_size = px_args32.coal_info_size;
+			px_args.coal_info = CAST_USER_ADDR_T(px_args32.coal_info);
+			px_args.persona_info_size = px_args32.persona_info_size;
+			px_args.persona_info = CAST_USER_ADDR_T(px_args32.persona_info);
+			px_args.posix_cred_info_size = px_args32.posix_cred_info_size;
+			px_args.posix_cred_info = CAST_USER_ADDR_T(px_args32.posix_cred_info);
+		}
+		if (error) {
+			goto bad;
+		}
+
+		if (px_args.attr_size != 0) {
+			/*
+			 * We are not copying the port_actions pointer,
+			 * because we already have it from px_args.
+			 * This is a bit fragile: <rdar://problem/16427422>
+			 */
+
+			if ((error = copyin(px_args.attrp, &px_sa, px_sa_offset)) != 0) {
+				goto bad;
+			}
+
+			bzero((void *)((unsigned long) &px_sa + px_sa_offset), sizeof(px_sa) - px_sa_offset );
+
+			imgp->ip_px_sa = &px_sa;
+		}
+		if (px_args.file_actions_size != 0) {
+			/* Limit file_actions to allowed number of open files */
+			int maxfa = (p->p_limit ? p->p_rlimit[RLIMIT_NOFILE].rlim_cur : NOFILE);
+			size_t maxfa_size = PSF_ACTIONS_SIZE(maxfa);
+			if (px_args.file_actions_size < PSF_ACTIONS_SIZE(1) ||
+			    maxfa_size == 0 || px_args.file_actions_size > maxfa_size) {
+				error = EINVAL;
+				goto bad;
+			}
+			MALLOC(px_sfap, _posix_spawn_file_actions_t, px_args.file_actions_size, M_TEMP, M_WAITOK);
+			if (px_sfap == NULL) {
+				error = ENOMEM;
+				goto bad;
+			}
+			imgp->ip_px_sfa = px_sfap;
+
+			if ((error = copyin(px_args.file_actions, px_sfap,
+			    px_args.file_actions_size)) != 0) {
+				goto bad;
+			}
+
+			/* Verify that the action count matches the struct size */
+			size_t psfsize = PSF_ACTIONS_SIZE(px_sfap->psfa_act_count);
+			if (psfsize == 0 || psfsize != px_args.file_actions_size) {
+				error = EINVAL;
+				goto bad;
+			}
+		}
+		if (px_args.port_actions_size != 0) {
+			/* Limit port_actions to one page of data */
+			if (px_args.port_actions_size < PS_PORT_ACTIONS_SIZE(1) ||
+			    px_args.port_actions_size > PAGE_SIZE) {
+				error = EINVAL;
+				goto bad;
+			}
+
+			MALLOC(px_spap, _posix_spawn_port_actions_t,
+			    px_args.port_actions_size, M_TEMP, M_WAITOK);
+			if (px_spap == NULL) {
+				error = ENOMEM;
+				goto bad;
+			}
+			imgp->ip_px_spa = px_spap;
+
+			if ((error = copyin(px_args.port_actions, px_spap,
+			    px_args.port_actions_size)) != 0) {
+				goto bad;
+			}
+
+			/* Verify that the action count matches the struct size */
+			size_t pasize = PS_PORT_ACTIONS_SIZE(px_spap->pspa_count);
+			if (pasize == 0 || pasize != px_args.port_actions_size) {
+				error = EINVAL;
+				goto bad;
+			}
+		}
+#if CONFIG_PERSONAS
+		/* copy in the persona info */
+		if (px_args.persona_info_size != 0 && px_args.persona_info != 0) {
+			/* for now, we need the exact same struct in user space */
+			if (px_args.persona_info_size != sizeof(*px_persona)) {
+				error = ERANGE;
+				goto bad;
+			}
+
+			MALLOC(px_persona, struct _posix_spawn_persona_info *, px_args.persona_info_size, M_TEMP, M_WAITOK | M_ZERO);
+			if (px_persona == NULL) {
+				error = ENOMEM;
+				goto bad;
+			}
+			imgp->ip_px_persona = px_persona;
+
+			if ((error = copyin(px_args.persona_info, px_persona,
+			    px_args.persona_info_size)) != 0) {
+				goto bad;
+			}
+			if ((error = spawn_validate_persona(px_persona)) != 0) {
+				goto bad;
+			}
+		}
+#endif
+		/* copy in the posix cred info */
+		if (px_args.posix_cred_info_size != 0 && px_args.posix_cred_info != 0) {
+			/* for now, we need the exact same struct in user space */
+			if (px_args.posix_cred_info_size != sizeof(*px_pcred_info)) {
+				error = ERANGE;
+				goto bad;
+			}
+
+			if (!kauth_cred_issuser(kauth_cred_get())) {
+				error = EPERM;
+				goto bad;
+			}
+
+			MALLOC(px_pcred_info, struct _posix_spawn_posix_cred_info *,
+			    px_args.posix_cred_info_size, M_TEMP, M_WAITOK | M_ZERO);
+			if (px_pcred_info == NULL) {
+				error = ENOMEM;
+				goto bad;
+			}
+			imgp->ip_px_pcred_info = px_pcred_info;
+
+			if ((error = copyin(px_args.posix_cred_info, px_pcred_info,
+			    px_args.posix_cred_info_size)) != 0) {
+				goto bad;
+			}
+
+			if (px_pcred_info->pspci_flags & POSIX_SPAWN_POSIX_CRED_GROUPS) {
+				if (px_pcred_info->pspci_ngroups > NGROUPS_MAX) {
+					error = EINVAL;
+					goto bad;
+				}
+			}
+		}
+#if CONFIG_MACF
+		if (px_args.mac_extensions_size != 0) {
+			if ((error = spawn_copyin_macpolicyinfo(&px_args, (_posix_spawn_mac_policy_extensions_t *)&imgp->ip_px_smpx)) != 0) {
+				goto bad;
+			}
+		}
+#endif /* CONFIG_MACF */
+	}
+
+	/* set uthread to parent */
+	uthread = get_bsdthread_info(current_thread());
+
+	/*
+	 * <rdar://6640530>; this does not result in a behaviour change
+	 * relative to Leopard, so there should not be any existing code
+	 * which depends on it.
+	 */
+	if (uthread->uu_flag & UT_VFORK) {
+		error = EINVAL;
+		goto bad;
+	}
+
+	if (imgp->ip_px_sa != NULL) {
+		struct _posix_spawnattr *psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
+		if ((error = exec_validate_spawnattr_policy(psa->psa_apptype)) != 0) {
+			goto bad;
+		}
+	}
+
+	/*
+	 * If we don't have the extension flag that turns "posix_spawn()"
+	 * into "execve() with options", then we will be creating a new
+	 * process which does not inherit memory from the parent process,
+	 * which is one of the most expensive things about using fork()
+	 * and execve().
+	 */
+	if (imgp->ip_px_sa == NULL || !(px_sa.psa_flags & POSIX_SPAWN_SETEXEC)) {
+		/* Set the new task's coalition, if it is requested.  */
+		coalition_t coal[COALITION_NUM_TYPES] = { COALITION_NULL };
+#if CONFIG_COALITIONS
+		int i, ncoals;
+		kern_return_t kr = KERN_SUCCESS;
+		struct _posix_spawn_coalition_info coal_info;
+		int coal_role[COALITION_NUM_TYPES];
+
+		if (imgp->ip_px_sa == NULL || !px_args.coal_info) {
+			goto do_fork1;
+		}
+
+		memset(&coal_info, 0, sizeof(coal_info));
+
+		if (px_args.coal_info_size > sizeof(coal_info)) {
+			px_args.coal_info_size = sizeof(coal_info);
+		}
+		error = copyin(px_args.coal_info,
+		    &coal_info, px_args.coal_info_size);
+		if (error != 0) {
+			goto bad;
+		}
+
+		ncoals = 0;
+		for (i = 0; i < COALITION_NUM_TYPES; i++) {
+			uint64_t cid = coal_info.psci_info[i].psci_id;
+			if (cid != 0) {
+				/*
+				 * don't allow tasks which are not in a
+				 * privileged coalition to spawn processes
+				 * into coalitions other than their own
+				 */
+				if (!task_is_in_privileged_coalition(p->task, i)) {
+					coal_dbg("ERROR: %d not in privilegd "
+					    "coalition of type %d",
+					    p->p_pid, i);
+					spawn_coalitions_release_all(coal);
+					error = EPERM;
+					goto bad;
+				}
+
+				coal_dbg("searching for coalition id:%llu", cid);
+				/*
+				 * take a reference and activation on the
+				 * coalition to guard against free-while-spawn
+				 * races
+				 */
+				coal[i] = coalition_find_and_activate_by_id(cid);
+				if (coal[i] == COALITION_NULL) {
+					coal_dbg("could not find coalition id:%llu "
+					    "(perhaps it has been terminated or reaped)", cid);
+					/*
+					 * release any other coalition's we
+					 * may have a reference to
+					 */
+					spawn_coalitions_release_all(coal);
+					error = ESRCH;
+					goto bad;
+				}
+				if (coalition_type(coal[i]) != i) {
+					coal_dbg("coalition with id:%lld is not of type:%d"
+					    " (it's type:%d)", cid, i, coalition_type(coal[i]));
+					error = ESRCH;
+					goto bad;
+				}
+				coal_role[i] = coal_info.psci_info[i].psci_role;
+				ncoals++;
+			}
+		}
+		if (ncoals < COALITION_NUM_TYPES) {
+			/*
+			 * If the user is attempting to spawn into a subset of
+			 * the known coalition types, then make sure they have
+			 * _at_least_ specified a resource coalition. If not,
+			 * the following fork1() call will implicitly force an
+			 * inheritance from 'p' and won't actually spawn the
+			 * new task into the coalitions the user specified.
+			 * (also the call to coalitions_set_roles will panic)
+			 */
+			if (coal[COALITION_TYPE_RESOURCE] == COALITION_NULL) {
+				spawn_coalitions_release_all(coal);
+				error = EINVAL;
+				goto bad;
+			}
+		}
+do_fork1:
+#endif /* CONFIG_COALITIONS */
+
+		/*
+		 * note that this will implicitly inherit the
+		 * caller's persona (if it exists)
+		 */
+		error = fork1(p, &imgp->ip_new_thread, PROC_CREATE_SPAWN, coal);
+		/* returns a thread and task reference */
+
+		if (error == 0) {
+			new_task = get_threadtask(imgp->ip_new_thread);
+		}
+#if CONFIG_COALITIONS
+		/* set the roles of this task within each given coalition */
+		if (error == 0) {
+			kr = coalitions_set_roles(coal, new_task, coal_role);
+			if (kr != KERN_SUCCESS) {
+				error = EINVAL;
+			}
+			if (kdebug_debugid_enabled(MACHDBG_CODE(DBG_MACH_COALITION,
+			    MACH_COALITION_ADOPT))) {
+				for (i = 0; i < COALITION_NUM_TYPES; i++) {
+					if (coal[i] != COALITION_NULL) {
+						/*
+						 * On 32-bit targets, uniqueid
+						 * will get truncated to 32 bits
+						 */
+						KDBG_RELEASE(MACHDBG_CODE(
+							    DBG_MACH_COALITION,
+							    MACH_COALITION_ADOPT),
+						    coalition_id(coal[i]),
+						    get_task_uniqueid(new_task));
+					}
+				}
+			}
+		}
+
+		/* drop our references and activations - fork1() now holds them */
+		spawn_coalitions_release_all(coal);
+#endif /* CONFIG_COALITIONS */
+		if (error != 0) {
+			goto bad;
+		}
+		imgp->ip_flags |= IMGPF_SPAWN;  /* spawn w/o exec */
+		spawn_no_exec = TRUE;           /* used in later tests */
+	} else {
+		/*
+		 * For execve case, create a new task and thread
+		 * which points to current_proc. The current_proc will point
+		 * to the new task after image activation and proc ref drain.
+		 *
+		 * proc (current_proc) <-----  old_task (current_task)
+		 *  ^ |                                ^
+		 *  | |                                |
+		 *  | ----------------------------------
+		 *  |
+		 *  --------- new_task (task marked as TF_EXEC_COPY)
+		 *
+		 * After image activation, the proc will point to the new task
+		 * and would look like following.
+		 *
+		 * proc (current_proc)  <-----  old_task (current_task, marked as TPF_DID_EXEC)
+		 *  ^ |
+		 *  | |
+		 *  | ----------> new_task
+		 *  |               |
+		 *  -----------------
+		 *
+		 * During exec any transition from new_task -> proc is fine, but don't allow
+		 * transition from proc->task, since it will modify old_task.
+		 */
+		imgp->ip_new_thread = fork_create_child(old_task,
+		    NULL,
+		    p,
+		    FALSE,
+		    p->p_flag & P_LP64,
+		    task_get_64bit_data(old_task),
+		    TRUE);
+		/* task and thread ref returned by fork_create_child */
+		if (imgp->ip_new_thread == NULL) {
+			error = ENOMEM;
+			goto bad;
+		}
+
+		new_task = get_threadtask(imgp->ip_new_thread);
+		imgp->ip_flags |= IMGPF_EXEC;
+	}
+
+	if (spawn_no_exec) {
+		p = (proc_t)get_bsdthreadtask_info(imgp->ip_new_thread);
+
+		/*
+		 * We had to wait until this point before firing the
+		 * proc:::create probe, otherwise p would not point to the
+		 * child process.
+		 */
+		DTRACE_PROC1(create, proc_t, p);
+	}
+	assert(p != NULL);
+
+	context.vc_thread = imgp->ip_new_thread;
+	context.vc_ucred = p->p_ucred;  /* XXX must NOT be kauth_cred_get() */
+
+	/*
+	 * Post fdcopy(), pre exec_handle_sugid() - this is where we want
+	 * to handle the file_actions.  Since vfork() also ends up setting
+	 * us into the parent process group, and saved off the signal flags,
+	 * this is also where we want to handle the spawn flags.
+	 */
+
+	/* Has spawn file actions? */
+	if (imgp->ip_px_sfa != NULL) {
+		/*
+		 * The POSIX_SPAWN_CLOEXEC_DEFAULT flag
+		 * is handled in exec_handle_file_actions().
+		 */
+		if ((error = exec_handle_file_actions(imgp,
+		    imgp->ip_px_sa != NULL ? px_sa.psa_flags : 0)) != 0) {
+			goto bad;
+		}
+	}
+
+	/* Has spawn port actions? */
+	if (imgp->ip_px_spa != NULL) {
+		if ((error = exec_handle_port_actions(imgp, &port_actions)) != 0) {
+			goto bad;
+		}
+	}
+
+	/* Has spawn attr? */
+	if (imgp->ip_px_sa != NULL) {
+		/*
+		 * Reset UID/GID to parent's RUID/RGID; This works only
+		 * because the operation occurs *after* the vfork() and
+		 * before the call to exec_handle_sugid() by the image
+		 * activator called from exec_activate_image().  POSIX
+		 * requires that any setuid/setgid bits on the process
+		 * image will take precedence over the spawn attributes
+		 * (re)setting them.
+		 *
+		 * Modifications to p_ucred must be guarded using the
+		 * proc's ucred lock. This prevents others from accessing
+		 * a garbage credential.
+		 */
+		if (px_sa.psa_flags & POSIX_SPAWN_RESETIDS) {
+			apply_kauth_cred_update(p, ^kauth_cred_t (kauth_cred_t my_cred){
+				return kauth_cred_setuidgid(my_cred,
+				kauth_cred_getruid(my_cred),
+				kauth_cred_getrgid(my_cred));
+			});
+		}
+
+		if (imgp->ip_px_pcred_info) {
+			if (!spawn_no_exec) {
+				error = ENOTSUP;
+				goto bad;
+			}
+
+			error = spawn_posix_cred_adopt(p, imgp->ip_px_pcred_info);
+			if (error != 0) {
+				goto bad;
+			}
+		}
+
+#if CONFIG_PERSONAS
+		if (imgp->ip_px_persona != NULL) {
+			if (!spawn_no_exec) {
+				error = ENOTSUP;
+				goto bad;
+			}
+
+			/*
+			 * If we were asked to spawn a process into a new persona,
+			 * do the credential switch now (which may override the UID/GID
+			 * inherit done just above). It's important to do this switch
+			 * before image activation both for reasons stated above, and
+			 * to ensure that the new persona has access to the image/file
+			 * being executed.
+			 */
+			error = spawn_persona_adopt(p, imgp->ip_px_persona);
+			if (error != 0) {
+				goto bad;
+			}
+		}
+#endif /* CONFIG_PERSONAS */
+#if !SECURE_KERNEL
+		/*
+		 * Disable ASLR for the spawned process.
+		 *
+		 * But only do so if we are not embedded + RELEASE.
+		 * While embedded allows for a boot-arg (-disable_aslr)
+		 * to deal with this (which itself is only honored on
+		 * DEVELOPMENT or DEBUG builds of xnu), it is often
+		 * useful or necessary to disable ASLR on a per-process
+		 * basis for unit testing and debugging.
+		 */
+		if (px_sa.psa_flags & _POSIX_SPAWN_DISABLE_ASLR) {
+			OSBitOrAtomic(P_DISABLE_ASLR, &p->p_flag);
+		}
+#endif /* !SECURE_KERNEL */
+
+		/* Randomize high bits of ASLR slide */
+		if (px_sa.psa_flags & _POSIX_SPAWN_HIGH_BITS_ASLR) {
+			imgp->ip_flags |= IMGPF_HIGH_BITS_ASLR;
+		}
+
+#if !SECURE_KERNEL
+		/*
+		 * Forcibly disallow execution from data pages for the spawned process
+		 * even if it would otherwise be permitted by the architecture default.
+		 */
+		if (px_sa.psa_flags & _POSIX_SPAWN_ALLOW_DATA_EXEC) {
+			imgp->ip_flags |= IMGPF_ALLOW_DATA_EXEC;
+		}
+#endif /* !SECURE_KERNEL */
+
+		if ((px_sa.psa_apptype & POSIX_SPAWN_PROC_TYPE_MASK) ==
+		    POSIX_SPAWN_PROC_TYPE_DRIVER) {
+			imgp->ip_flags |= IMGPF_DRIVER;
+		}
+	}
+
+	/*
+	 * Disable ASLR during image activation.  This occurs either if the
+	 * _POSIX_SPAWN_DISABLE_ASLR attribute was found above or if
+	 * P_DISABLE_ASLR was inherited from the parent process.
+	 */
+	if (p->p_flag & P_DISABLE_ASLR) {
+		imgp->ip_flags |= IMGPF_DISABLE_ASLR;
+	}
+
+	/*
+	 * Clear transition flag so we won't hang if exec_activate_image() causes
+	 * an automount (and launchd does a proc sysctl to service it).
+	 *
+	 * <rdar://problem/6848672>, <rdar://problem/5959568>.
+	 */
+	if (spawn_no_exec) {
+		proc_transend(p, 0);
+		proc_transit_set = 0;
+	}
+
+#if MAC_SPAWN   /* XXX */
+	if (uap->mac_p != USER_ADDR_NULL) {
+		error = mac_execve_enter(uap->mac_p, imgp);
+		if (error) {
+			goto bad;
+		}
+	}
+#endif
+
+	/*
+	 * Activate the image
+	 */
+	error = exec_activate_image(imgp);
+#if defined(HAS_APPLE_PAC)
+	ml_task_set_disable_user_jop(new_task, imgp->ip_flags & IMGPF_NOJOP ? TRUE : FALSE);
+	ml_thread_set_disable_user_jop(imgp->ip_new_thread, imgp->ip_flags & IMGPF_NOJOP ? TRUE : FALSE);
+#endif
+
+	if (error == 0 && !spawn_no_exec) {
+		p = proc_exec_switch_task(p, old_task, new_task, imgp->ip_new_thread);
+		/* proc ref returned */
+		should_release_proc_ref = TRUE;
+
+		/*
+		 * Need to transfer pending watch port boosts to the new task while still making
+		 * sure that the old task remains in the importance linkage. Create an importance
+		 * linkage from old task to new task, then switch the task importance base
+		 * of old task and new task. After the switch the port watch boost will be
+		 * boosting the new task and new task will be donating importance to old task.
+		 */
+		inherit = ipc_importance_exec_switch_task(old_task, new_task);
+	}
+
+	if (error == 0) {
+		/* process completed the exec */
+		exec_done = TRUE;
+	} else if (error == -1) {
+		/* Image not claimed by any activator? */
+		error = ENOEXEC;
+	}
+
+	if (!error && imgp->ip_px_sa != NULL) {
+		thread_t child_thread = imgp->ip_new_thread;
+		uthread_t child_uthread = get_bsdthread_info(child_thread);
+
+		/*
+		 * Because of POSIX_SPAWN_SETEXEC, we need to handle this after image
+		 * activation, else when image activation fails (before the point of no
+		 * return) would leave the parent process in a modified state.
+		 */
+		if (px_sa.psa_flags & POSIX_SPAWN_SETPGROUP) {
+			struct setpgid_args spga;
+			spga.pid = p->p_pid;
+			spga.pgid = px_sa.psa_pgroup;
+			/*
+			 * Effectively, call setpgid() system call; works
+			 * because there are no pointer arguments.
+			 */
+			if ((error = setpgid(p, &spga, ival)) != 0) {
+				goto bad;
+			}
+		}
+
+		if (px_sa.psa_flags & POSIX_SPAWN_SETSID) {
+			error = setsid_internal(p);
+			if (error != 0) {
+				goto bad;
+			}
+		}
+
+		/*
+		 * If we have a spawn attr, and it contains signal related flags,
+		 * the we need to process them in the "context" of the new child
+		 * process, so we have to process it following image activation,
+		 * prior to making the thread runnable in user space.  This is
+		 * necessitated by some signal information being per-thread rather
+		 * than per-process, and we don't have the new allocation in hand
+		 * until after the image is activated.
+		 */
+
+		/*
+		 * Mask a list of signals, instead of them being unmasked, if
+		 * they were unmasked in the parent; note that some signals
+		 * are not maskable.
+		 */
+		if (px_sa.psa_flags & POSIX_SPAWN_SETSIGMASK) {
+			child_uthread->uu_sigmask = (px_sa.psa_sigmask & ~sigcantmask);
+		}
+		/*
+		 * Default a list of signals instead of ignoring them, if
+		 * they were ignored in the parent.  Note that we pass
+		 * spawn_no_exec to setsigvec() to indicate that we called
+		 * fork1() and therefore do not need to call proc_signalstart()
+		 * internally.
+		 */
+		if (px_sa.psa_flags & POSIX_SPAWN_SETSIGDEF) {
+			vec.sa_handler = SIG_DFL;
+			vec.sa_tramp = 0;
+			vec.sa_mask = 0;
+			vec.sa_flags = 0;
+			for (sig = 1; sig < NSIG; sig++) {
+				if (px_sa.psa_sigdefault & (1 << (sig - 1))) {
+					error = setsigvec(p, child_thread, sig, &vec, spawn_no_exec);
+				}
+			}
+		}
+
+		/*
+		 * Activate the CPU usage monitor, if requested. This is done via a task-wide, per-thread CPU
+		 * usage limit, which will generate a resource exceeded exception if any one thread exceeds the
+		 * limit.
+		 *
+		 * Userland gives us interval in seconds, and the kernel SPI expects nanoseconds.
+		 */
+		if (px_sa.psa_cpumonitor_percent != 0) {
+			/*
+			 * Always treat a CPU monitor activation coming from spawn as entitled. Requiring
+			 * an entitlement to configure the monitor a certain way seems silly, since
+			 * whomever is turning it on could just as easily choose not to do so.
+			 */
+			error = proc_set_task_ruse_cpu(p->task,
+			    TASK_POLICY_RESOURCE_ATTRIBUTE_NOTIFY_EXC,
+			    px_sa.psa_cpumonitor_percent,
+			    px_sa.psa_cpumonitor_interval * NSEC_PER_SEC,
+			    0, TRUE);
+		}
+
+
+		if (px_pcred_info &&
+		    (px_pcred_info->pspci_flags & POSIX_SPAWN_POSIX_CRED_LOGIN)) {
+			/*
+			 * setlogin() must happen after setsid()
+			 */
+			setlogin_internal(p, px_pcred_info->pspci_login);
+		}
+	}
+
+bad:
+
+	if (error == 0) {
+		/* reset delay idle sleep status if set */
+#if !CONFIG_EMBEDDED
+		if ((p->p_flag & P_DELAYIDLESLEEP) == P_DELAYIDLESLEEP) {
+			OSBitAndAtomic(~((uint32_t)P_DELAYIDLESLEEP), &p->p_flag);
+		}
+#endif /* !CONFIG_EMBEDDED */
+		/* upon  successful spawn, re/set the proc control state */
+		if (imgp->ip_px_sa != NULL) {
+			switch (px_sa.psa_pcontrol) {
+			case POSIX_SPAWN_PCONTROL_THROTTLE:
+				p->p_pcaction = P_PCTHROTTLE;
+				break;
+			case POSIX_SPAWN_PCONTROL_SUSPEND:
+				p->p_pcaction = P_PCSUSP;
+				break;
+			case POSIX_SPAWN_PCONTROL_KILL:
+				p->p_pcaction = P_PCKILL;
+				break;
+			case POSIX_SPAWN_PCONTROL_NONE:
+			default:
+				p->p_pcaction = 0;
+				break;
+			}
+			;
+		}
+		exec_resettextvp(p, imgp);
+
+#if CONFIG_MEMORYSTATUS
+		/* Set jetsam priority for DriverKit processes */
+		if (px_sa.psa_apptype == POSIX_SPAWN_PROC_TYPE_DRIVER) {
+			px_sa.psa_priority = JETSAM_PRIORITY_DRIVER_APPLE;
+		}
+
+		/* Has jetsam attributes? */
+		if (imgp->ip_px_sa != NULL && (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_SET)) {
+			/*
+			 * With 2-level high-water-mark support, POSIX_SPAWN_JETSAM_HIWATER_BACKGROUND is no
+			 * longer relevant, as background limits are described via the inactive limit slots.
+			 *
+			 * That said, however, if the POSIX_SPAWN_JETSAM_HIWATER_BACKGROUND is passed in,
+			 * we attempt to mimic previous behavior by forcing the BG limit data into the
+			 * inactive/non-fatal mode and force the active slots to hold system_wide/fatal mode.
+			 */
+
+			if (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_HIWATER_BACKGROUND) {
+				memorystatus_update(p, px_sa.psa_priority, 0, FALSE, /* assertion priority */
+				    (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_USE_EFFECTIVE_PRIORITY),
+				    TRUE,
+				    -1, TRUE,
+				    px_sa.psa_memlimit_inactive, FALSE);
+			} else {
+				memorystatus_update(p, px_sa.psa_priority, 0, FALSE, /* assertion priority */
+				    (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_USE_EFFECTIVE_PRIORITY),
+				    TRUE,
+				    px_sa.psa_memlimit_active,
+				    (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_MEMLIMIT_ACTIVE_FATAL),
+				    px_sa.psa_memlimit_inactive,
+				    (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_MEMLIMIT_INACTIVE_FATAL));
+			}
+		}
+
+		/* Has jetsam relaunch behavior? */
+		if (imgp->ip_px_sa != NULL && (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_RELAUNCH_BEHAVIOR_MASK)) {
+			/*
+			 * Launchd has passed in data indicating the behavior of this process in response to jetsam.
+			 * This data would be used by the jetsam subsystem to determine the position and protection
+			 * offered to this process on dirty -> clean transitions.
+			 */
+			int relaunch_flags = P_MEMSTAT_RELAUNCH_UNKNOWN;
+			switch (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_RELAUNCH_BEHAVIOR_MASK) {
+			case POSIX_SPAWN_JETSAM_RELAUNCH_BEHAVIOR_LOW:
+				relaunch_flags = P_MEMSTAT_RELAUNCH_LOW;
+				break;
+			case POSIX_SPAWN_JETSAM_RELAUNCH_BEHAVIOR_MED:
+				relaunch_flags = P_MEMSTAT_RELAUNCH_MED;
+				break;
+			case POSIX_SPAWN_JETSAM_RELAUNCH_BEHAVIOR_HIGH:
+				relaunch_flags = P_MEMSTAT_RELAUNCH_HIGH;
+				break;
+			default:
+				break;
+			}
+			memorystatus_relaunch_flags_update(p, relaunch_flags);
+		}
+
+#endif /* CONFIG_MEMORYSTATUS */
+		if (imgp->ip_px_sa != NULL && px_sa.psa_thread_limit > 0) {
+			task_set_thread_limit(new_task, (uint16_t)px_sa.psa_thread_limit);
+		}
+	}
+
+	/*
+	 * If we successfully called fork1(), we always need to do this;
+	 * we identify this case by noting the IMGPF_SPAWN flag.  This is
+	 * because we come back from that call with signals blocked in the
+	 * child, and we have to unblock them, but we want to wait until
+	 * after we've performed any spawn actions.  This has to happen
+	 * before check_for_signature(), which uses psignal.
+	 */
+	if (spawn_no_exec) {
+		if (proc_transit_set) {
+			proc_transend(p, 0);
+		}
+
+		/*
+		 * Drop the signal lock on the child which was taken on our
+		 * behalf by forkproc()/cloneproc() to prevent signals being
+		 * received by the child in a partially constructed state.
+		 */
+		proc_signalend(p, 0);
+
+		/* flag the 'fork' has occurred */
+		proc_knote(p->p_pptr, NOTE_FORK | p->p_pid);
+	}
+
+	/* flag exec has occurred, notify only if it has not failed due to FP Key error */
+	if (!error && ((p->p_lflag & P_LTERM_DECRYPTFAIL) == 0)) {
+		proc_knote(p, NOTE_EXEC);
+	}
+
+
+	if (error == 0) {
+		/*
+		 * We need to initialize the bank context behind the protection of
+		 * the proc_trans lock to prevent a race with exit. We can't do this during
+		 * exec_activate_image because task_bank_init checks entitlements that
+		 * aren't loaded until subsequent calls (including exec_resettextvp).
+		 */
+		error = proc_transstart(p, 0, 0);
+
+		if (error == 0) {
+			task_bank_init(new_task);
+			proc_transend(p, 0);
+		}
+
+#if __arm64__
+		proc_legacy_footprint_entitled(p, new_task, __FUNCTION__);
+#endif /* __arm64__ */
+	}
+
+	/* Inherit task role from old task to new task for exec */
+	if (error == 0 && !spawn_no_exec) {
+		proc_inherit_task_role(new_task, old_task);
+	}
+
+#if CONFIG_ARCADE
+	if (error == 0) {
+		/*
+		 * Check to see if we need to trigger an arcade upcall AST now
+		 * that the vnode has been reset on the task.
+		 */
+		arcade_prepare(new_task, imgp->ip_new_thread);
+	}
+#endif /* CONFIG_ARCADE */
+
+	/* Clear the initial wait on the thread before handling spawn policy */
+	if (imgp && imgp->ip_new_thread) {
+		task_clear_return_wait(get_threadtask(imgp->ip_new_thread), TCRW_CLEAR_INITIAL_WAIT);
+	}
+
+	/*
+	 * Apply the spawnattr policy, apptype (which primes the task for importance donation),
+	 * and bind any portwatch ports to the new task.
+	 * This must be done after the exec so that the child's thread is ready,
+	 * and after the in transit state has been released, because priority is
+	 * dropped here so we need to be prepared for a potentially long preemption interval
+	 *
+	 * TODO: Consider splitting this up into separate phases
+	 */
+	if (error == 0 && imgp->ip_px_sa != NULL) {
+		struct _posix_spawnattr *psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
+
+		error = exec_handle_spawnattr_policy(p, imgp->ip_new_thread, psa->psa_apptype, psa->psa_qos_clamp,
+		    psa->psa_darwin_role, &port_actions);
+	}
+
+	/* Transfer the turnstile watchport boost to new task if in exec */
+	if (error == 0 && !spawn_no_exec) {
+		task_transfer_turnstile_watchports(old_task, new_task, imgp->ip_new_thread);
+	}
+
+	/*
+	 * Apply the requested maximum address.
+	 */
+	if (error == 0 && imgp->ip_px_sa != NULL) {
+		struct _posix_spawnattr *psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
+
+		if (psa->psa_max_addr) {
+			vm_map_set_max_addr(get_task_map(new_task), psa->psa_max_addr);
+		}
+	}
+
+	if (error == 0) {
+		/* Apply the main thread qos */
+		thread_t main_thread = imgp->ip_new_thread;
+		task_set_main_thread_qos(new_task, main_thread);
+
+#if CONFIG_MACF
+		/*
+		 * Processes with the MAP_JIT entitlement are permitted to have
+		 * a jumbo-size map.
+		 */
+		if (mac_proc_check_map_anon(p, 0, 0, 0, MAP_JIT, NULL) == 0) {
+			vm_map_set_jumbo(get_task_map(new_task));
+			vm_map_set_jit_entitled(get_task_map(new_task));
+		}
+#endif /* CONFIG_MACF */
+	}
+
+	/*
+	 * Release any ports we kept around for binding to the new task
+	 * We need to release the rights even if the posix_spawn has failed.
+	 */
+	if (imgp->ip_px_spa != NULL) {
+		exec_port_actions_destroy(&port_actions);
+	}
+
+	/*
+	 * We have to delay operations which might throw a signal until after
+	 * the signals have been unblocked; however, we want that to happen
+	 * after exec_resettextvp() so that the textvp is correct when they
+	 * fire.
+	 */
+	if (error == 0) {
+		error = check_for_signature(p, imgp);
+
+		/*
+		 * Pay for our earlier safety; deliver the delayed signals from
+		 * the incomplete spawn process now that it's complete.
+		 */
+		if (imgp != NULL && spawn_no_exec && (p->p_lflag & P_LTRACED)) {
+			psignal_vfork(p, p->task, imgp->ip_new_thread, SIGTRAP);
+		}
+
+		if (error == 0 && !spawn_no_exec) {
+			KDBG(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXEC),
+			    p->p_pid);
+		}
+	}
+
+
+	if (imgp != NULL) {
+		if (imgp->ip_vp) {
+			vnode_put(imgp->ip_vp);
+		}
+		if (imgp->ip_scriptvp) {
+			vnode_put(imgp->ip_scriptvp);
+		}
+		if (imgp->ip_strings) {
+			execargs_free(imgp);
+		}
+		if (imgp->ip_px_sfa != NULL) {
+			FREE(imgp->ip_px_sfa, M_TEMP);
+		}
+		if (imgp->ip_px_spa != NULL) {
+			FREE(imgp->ip_px_spa, M_TEMP);
+		}
+#if CONFIG_PERSONAS
+		if (imgp->ip_px_persona != NULL) {
+			FREE(imgp->ip_px_persona, M_TEMP);
+		}
+#endif
+		if (imgp->ip_px_pcred_info != NULL) {
+			FREE(imgp->ip_px_pcred_info, M_TEMP);
+		}
+#if CONFIG_MACF
+		if (imgp->ip_px_smpx != NULL) {
+			spawn_free_macpolicyinfo(imgp->ip_px_smpx);
+		}
+		if (imgp->ip_execlabelp) {
+			mac_cred_label_free(imgp->ip_execlabelp);
+		}
+		if (imgp->ip_scriptlabelp) {
+			mac_vnode_label_free(imgp->ip_scriptlabelp);
+		}
+		if (imgp->ip_cs_error != OS_REASON_NULL) {
+			os_reason_free(imgp->ip_cs_error);
+			imgp->ip_cs_error = OS_REASON_NULL;
+		}
+#endif
+	}
+
+#if CONFIG_DTRACE
+	if (spawn_no_exec) {
+		/*
+		 * In the original DTrace reference implementation,
+		 * posix_spawn() was a libc routine that just
+		 * did vfork(2) then exec(2).  Thus the proc::: probes
+		 * are very fork/exec oriented.  The details of this
+		 * in-kernel implementation of posix_spawn() is different
+		 * (while producing the same process-observable effects)
+		 * particularly w.r.t. errors, and which thread/process
+		 * is constructing what on behalf of whom.
+		 */
+		if (error) {
+			DTRACE_PROC1(spawn__failure, int, error);
+		} else {
+			DTRACE_PROC(spawn__success);
+			/*
+			 * Some DTrace scripts, e.g. newproc.d in
+			 * /usr/bin, rely on the the 'exec-success'
+			 * probe being fired in the child after the
+			 * new process image has been constructed
+			 * in order to determine the associated pid.
+			 *
+			 * So, even though the parent built the image
+			 * here, for compatibility, mark the new thread
+			 * so 'exec-success' fires on it as it leaves
+			 * the kernel.
+			 */
+			dtrace_thread_didexec(imgp->ip_new_thread);
+		}
+	} else {
+		if (error) {
+			DTRACE_PROC1(exec__failure, int, error);
+		} else {
+			dtrace_thread_didexec(imgp->ip_new_thread);
+		}
+	}
+
+	if ((dtrace_proc_waitfor_hook = dtrace_proc_waitfor_exec_ptr) != NULL) {
+		(*dtrace_proc_waitfor_hook)(p);
+	}
+#endif
+
+#if CONFIG_AUDIT
+	if (!error && AUDIT_ENABLED() && p) {
+		/* Add the CDHash of the new process to the audit record */
+		uint8_t *cdhash = cs_get_cdhash(p);
+		if (cdhash) {
+			AUDIT_ARG(data, cdhash, sizeof(uint8_t), CS_CDHASH_LEN);
+		}
+	}
+#endif
+
+	/*
+	 * clear bsd_info from old task if it did exec.
+	 */
+	if (task_did_exec(old_task)) {
+		set_bsdtask_info(old_task, NULL);
+	}
+
+	/* clear bsd_info from new task and terminate it if exec failed  */
+	if (new_task != NULL && task_is_exec_copy(new_task)) {
+		set_bsdtask_info(new_task, NULL);
+		task_terminate_internal(new_task);
+	}
+
+	/* Return to both the parent and the child? */
+	if (imgp != NULL && spawn_no_exec) {
+		/*
+		 * If the parent wants the pid, copy it out
+		 */
+		if (pid != USER_ADDR_NULL) {
+			_Static_assert(sizeof(p->p_pid) == 4, "posix_spawn() assumes a 32-bit pid_t");
+			bool aligned = (pid & 3) == 0;
+			if (aligned) {
+				(void)copyout_atomic32(p->p_pid, pid);
+			} else {
+				(void)suword(pid, p->p_pid);
+			}
+		}
+		retval[0] = error;
+
+		/*
+		 * If we had an error, perform an internal reap ; this is
+		 * entirely safe, as we have a real process backing us.
+		 */
+		if (error) {
+			proc_list_lock();
+			p->p_listflag |= P_LIST_DEADPARENT;
+			proc_list_unlock();
+			proc_lock(p);
+			/* make sure no one else has killed it off... */
+			if (p->p_stat != SZOMB && p->exit_thread == NULL) {
+				p->exit_thread = current_thread();
+				proc_unlock(p);
+				exit1(p, 1, (int *)NULL);
+			} else {
+				/* someone is doing it for us; just skip it */
+				proc_unlock(p);
+			}
+		}
+	}
+
+	/*
+	 * Do not terminate the current task, if proc_exec_switch_task did not
+	 * switch the tasks, terminating the current task without the switch would
+	 * result in loosing the SIGKILL status.
+	 */
+	if (task_did_exec(old_task)) {
+		/* Terminate the current task, since exec will start in new task */
+		task_terminate_internal(old_task);
+	}
+
+	/* Release the thread ref returned by fork_create_child/fork1 */
+	if (imgp != NULL && imgp->ip_new_thread) {
+		/* wake up the new thread */
+		task_clear_return_wait(get_threadtask(imgp->ip_new_thread), TCRW_CLEAR_FINAL_WAIT);
+		thread_deallocate(imgp->ip_new_thread);
+		imgp->ip_new_thread = NULL;
+	}
+
+	/* Release the ref returned by fork_create_child/fork1 */
+	if (new_task) {
+		task_deallocate(new_task);
+		new_task = NULL;
+	}
+
+	if (should_release_proc_ref) {
+		proc_rele(p);
+	}
+
+	if (bufp != NULL) {
+		FREE(bufp, M_TEMP);
+	}
+
+	if (inherit != NULL) {
+		ipc_importance_release(inherit);
+	}
+
+	return error;
+}
+
+/*
+ * proc_exec_switch_task
+ *
+ * Parameters:  p			proc
+ *		old_task		task before exec
+ *		new_task		task after exec
+ *		new_thread		thread in new task
+ *
+ * Returns: proc.
+ *
+ * Note: The function will switch the task pointer of proc
+ * from old task to new task. The switch needs to happen
+ * after draining all proc refs and inside a proc translock.
+ * In the case of failure to switch the task, which might happen
+ * if the process received a SIGKILL or jetsam killed it, it will make
+ * sure that the new tasks terminates. User proc ref returned
+ * to caller.
+ *
+ * This function is called after point of no return, in the case
+ * failure to switch, it will terminate the new task and swallow the
+ * error and let the terminated process complete exec and die.
+ */
+proc_t
+proc_exec_switch_task(proc_t p, task_t old_task, task_t new_task, thread_t new_thread)
+{
+	int error = 0;
+	boolean_t task_active;
+	boolean_t proc_active;
+	boolean_t thread_active;
+	thread_t old_thread = current_thread();
+
+	/*
+	 * Switch the task pointer of proc to new task.
+	 * Before switching the task, wait for proc_refdrain.
+	 * After the switch happens, the proc can disappear,
+	 * take a ref before it disappears. Waiting for
+	 * proc_refdrain in exec will block all other threads
+	 * trying to take a proc ref, boost the current thread
+	 * to avoid priority inversion.
+	 */
+	thread_set_exec_promotion(old_thread);
+	p = proc_refdrain_with_refwait(p, TRUE);
+	/* extra proc ref returned to the caller */
+
+	assert(get_threadtask(new_thread) == new_task);
+	task_active = task_is_active(new_task);
+
+	/* Take the proc_translock to change the task ptr */
+	proc_lock(p);
+	proc_active = !(p->p_lflag & P_LEXIT);
+
+	/* Check if the current thread is not aborted due to SIGKILL */
+	thread_active = thread_is_active(old_thread);
+
+	/*
+	 * Do not switch the task if the new task or proc is already terminated
+	 * as a result of error in exec past point of no return
+	 */
+	if (proc_active && task_active && thread_active) {
+		error = proc_transstart(p, 1, 0);
+		if (error == 0) {
+			uthread_t new_uthread = get_bsdthread_info(new_thread);
+			uthread_t old_uthread = get_bsdthread_info(current_thread());
+
+			/*
+			 * bsd_info of old_task will get cleared in execve and posix_spawn
+			 * after firing exec-success/error dtrace probe.
+			 */
+			p->task = new_task;
+
+			/* Clear dispatchqueue and workloop ast offset */
+			p->p_dispatchqueue_offset = 0;
+			p->p_dispatchqueue_serialno_offset = 0;
+			p->p_dispatchqueue_label_offset = 0;
+			p->p_return_to_kernel_offset = 0;
+
+			/* Copy the signal state, dtrace state and set bsd ast on new thread */
+			act_set_astbsd(new_thread);
+			new_uthread->uu_siglist = old_uthread->uu_siglist;
+			new_uthread->uu_sigwait = old_uthread->uu_sigwait;
+			new_uthread->uu_sigmask = old_uthread->uu_sigmask;
+			new_uthread->uu_oldmask = old_uthread->uu_oldmask;
+			new_uthread->uu_vforkmask = old_uthread->uu_vforkmask;
+			new_uthread->uu_exit_reason = old_uthread->uu_exit_reason;
+#if CONFIG_DTRACE
+			new_uthread->t_dtrace_sig = old_uthread->t_dtrace_sig;
+			new_uthread->t_dtrace_stop = old_uthread->t_dtrace_stop;
+			new_uthread->t_dtrace_resumepid = old_uthread->t_dtrace_resumepid;
+			assert(new_uthread->t_dtrace_scratch == NULL);
+			new_uthread->t_dtrace_scratch = old_uthread->t_dtrace_scratch;
+
+			old_uthread->t_dtrace_sig = 0;
+			old_uthread->t_dtrace_stop = 0;
+			old_uthread->t_dtrace_resumepid = 0;
+			old_uthread->t_dtrace_scratch = NULL;
+#endif
+			/* Copy the resource accounting info */
+			thread_copy_resource_info(new_thread, current_thread());
+
+			/* Clear the exit reason and signal state on old thread */
+			old_uthread->uu_exit_reason = NULL;
+			old_uthread->uu_siglist = 0;
+
+			/* Add the new uthread to proc uthlist and remove the old one */
+			TAILQ_INSERT_TAIL(&p->p_uthlist, new_uthread, uu_list);
+			TAILQ_REMOVE(&p->p_uthlist, old_uthread, uu_list);
+
+			task_set_did_exec_flag(old_task);
+			task_clear_exec_copy_flag(new_task);
+
+			task_copy_fields_for_exec(new_task, old_task);
+
+			proc_transend(p, 1);
+		}
+	}
+
+	proc_unlock(p);
+	proc_refwake(p);
+	thread_clear_exec_promotion(old_thread);
+
+	if (error != 0 || !task_active || !proc_active || !thread_active) {
+		task_terminate_internal(new_task);
+	}
+
+	return p;
+}
+
+/*
+ * execve
+ *
+ * Parameters:	uap->fname		File name to exec
+ *		uap->argp		Argument list
+ *		uap->envp		Environment list
+ *
+ * Returns:	0			Success
+ *	__mac_execve:EINVAL		Invalid argument
+ *	__mac_execve:ENOTSUP		Invalid argument
+ *	__mac_execve:EACCES		Permission denied
+ *	__mac_execve:EINTR		Interrupted function
+ *	__mac_execve:ENOMEM		Not enough space
+ *	__mac_execve:EFAULT		Bad address
+ *	__mac_execve:ENAMETOOLONG	Filename too long
+ *	__mac_execve:ENOEXEC		Executable file format error
+ *	__mac_execve:ETXTBSY		Text file busy [misuse of error code]
+ *	__mac_execve:???
+ *
+ * TODO:	Dynamic linker header address on stack is copied via suword()
+ */
+/* ARGSUSED */
+int
+execve(proc_t p, struct execve_args *uap, int32_t *retval)
+{
+	struct __mac_execve_args muap;
+	int err;
+
+	memoryshot(VM_EXECVE, DBG_FUNC_NONE);
+
+	muap.fname = uap->fname;
+	muap.argp = uap->argp;
+	muap.envp = uap->envp;
+	muap.mac_p = USER_ADDR_NULL;
+	err = __mac_execve(p, &muap, retval);
+
+	return err;
+}
+
+/*
+ * __mac_execve
+ *
+ * Parameters:	uap->fname		File name to exec
+ *		uap->argp		Argument list
+ *		uap->envp		Environment list
+ *		uap->mac_p		MAC label supplied by caller
+ *
+ * Returns:	0			Success
+ *		EINVAL			Invalid argument
+ *		ENOTSUP			Not supported
+ *		ENOEXEC			Executable file format error
+ *	exec_activate_image:EINVAL	Invalid argument
+ *	exec_activate_image:EACCES	Permission denied
+ *	exec_activate_image:EINTR	Interrupted function
+ *	exec_activate_image:ENOMEM	Not enough space
+ *	exec_activate_image:EFAULT	Bad address
+ *	exec_activate_image:ENAMETOOLONG	Filename too long
+ *	exec_activate_image:ENOEXEC	Executable file format error
+ *	exec_activate_image:ETXTBSY	Text file busy [misuse of error code]
+ *	exec_activate_image:EBADEXEC	The executable is corrupt/unknown
+ *	exec_activate_image:???
+ *	mac_execve_enter:???
+ *
+ * TODO:	Dynamic linker header address on stack is copied via suword()
+ */
+int
+__mac_execve(proc_t p, struct __mac_execve_args *uap, int32_t *retval)
+{
+	char *bufp = NULL;
+	struct image_params *imgp;
+	struct vnode_attr *vap;
+	struct vnode_attr *origvap;
+	int error;
+	int is_64 = IS_64BIT_PROCESS(p);
+	struct vfs_context context;
+	struct uthread  *uthread;
+	task_t old_task = current_task();
+	task_t new_task = NULL;
+	boolean_t should_release_proc_ref = FALSE;
+	boolean_t exec_done = FALSE;
+	boolean_t in_vfexec = FALSE;
+	void *inherit = NULL;
+
+	context.vc_thread = current_thread();
+	context.vc_ucred = kauth_cred_proc_ref(p);      /* XXX must NOT be kauth_cred_get() */
+
+	/* Allocate a big chunk for locals instead of using stack since these
+	 * structures a pretty big.
+	 */
+	MALLOC(bufp, char *, (sizeof(*imgp) + sizeof(*vap) + sizeof(*origvap)), M_TEMP, M_WAITOK | M_ZERO);
+	imgp = (struct image_params *) bufp;
+	if (bufp == NULL) {
+		error = ENOMEM;
+		goto exit_with_error;
+	}
+	vap = (struct vnode_attr *) (bufp + sizeof(*imgp));
+	origvap = (struct vnode_attr *) (bufp + sizeof(*imgp) + sizeof(*vap));
+
+	/* Initialize the common data in the image_params structure */
+	imgp->ip_user_fname = uap->fname;
+	imgp->ip_user_argv = uap->argp;
+	imgp->ip_user_envv = uap->envp;
+	imgp->ip_vattr = vap;
+	imgp->ip_origvattr = origvap;
+	imgp->ip_vfs_context = &context;
+	imgp->ip_flags = (is_64 ? IMGPF_WAS_64BIT_ADDR : IMGPF_NONE) | ((p->p_flag & P_DISABLE_ASLR) ? IMGPF_DISABLE_ASLR : IMGPF_NONE);
+	imgp->ip_seg = (is_64 ? UIO_USERSPACE64 : UIO_USERSPACE32);
+	imgp->ip_mac_return = 0;
+	imgp->ip_cs_error = OS_REASON_NULL;
+	imgp->ip_simulator_binary = IMGPF_SB_DEFAULT;
+
+#if CONFIG_MACF
+	if (uap->mac_p != USER_ADDR_NULL) {
+		error = mac_execve_enter(uap->mac_p, imgp);
+		if (error) {
+			kauth_cred_unref(&context.vc_ucred);
+			goto exit_with_error;
+		}
+	}
+#endif
+	uthread = get_bsdthread_info(current_thread());
+	if (uthread->uu_flag & UT_VFORK) {
+		imgp->ip_flags |= IMGPF_VFORK_EXEC;
+		in_vfexec = TRUE;
+	} else {
+		imgp->ip_flags |= IMGPF_EXEC;
+
+		/*
+		 * For execve case, create a new task and thread
+		 * which points to current_proc. The current_proc will point
+		 * to the new task after image activation and proc ref drain.
+		 *
+		 * proc (current_proc) <-----  old_task (current_task)
+		 *  ^ |                                ^
+		 *  | |                                |
+		 *  | ----------------------------------
+		 *  |
+		 *  --------- new_task (task marked as TF_EXEC_COPY)
+		 *
+		 * After image activation, the proc will point to the new task
+		 * and would look like following.
+		 *
+		 * proc (current_proc)  <-----  old_task (current_task, marked as TPF_DID_EXEC)
+		 *  ^ |
+		 *  | |
+		 *  | ----------> new_task
+		 *  |               |
+		 *  -----------------
+		 *
+		 * During exec any transition from new_task -> proc is fine, but don't allow
+		 * transition from proc->task, since it will modify old_task.
+		 */
+		imgp->ip_new_thread = fork_create_child(old_task,
+		    NULL,
+		    p,
+		    FALSE,
+		    p->p_flag & P_LP64,
+		    task_get_64bit_data(old_task),
+		    TRUE);
+		/* task and thread ref returned by fork_create_child */
+		if (imgp->ip_new_thread == NULL) {
+			error = ENOMEM;
+			goto exit_with_error;
+		}
+
+		new_task = get_threadtask(imgp->ip_new_thread);
+		context.vc_thread = imgp->ip_new_thread;
+	}
+
+	error = exec_activate_image(imgp);
+	/* thread and task ref returned for vfexec case */
+
+	if (imgp->ip_new_thread != NULL) {
+		/*
+		 * task reference might be returned by exec_activate_image
+		 * for vfexec.
+		 */
+		new_task = get_threadtask(imgp->ip_new_thread);
+#if defined(HAS_APPLE_PAC)
+		ml_task_set_disable_user_jop(new_task, imgp->ip_flags & IMGPF_NOJOP ? TRUE : FALSE);
+		ml_thread_set_disable_user_jop(imgp->ip_new_thread, imgp->ip_flags & IMGPF_NOJOP ? TRUE : FALSE);
+#endif
+	}
+
+	if (!error && !in_vfexec) {
+		p = proc_exec_switch_task(p, old_task, new_task, imgp->ip_new_thread);
+		/* proc ref returned */
+		should_release_proc_ref = TRUE;
+
+		/*
+		 * Need to transfer pending watch port boosts to the new task while still making
+		 * sure that the old task remains in the importance linkage. Create an importance
+		 * linkage from old task to new task, then switch the task importance base
+		 * of old task and new task. After the switch the port watch boost will be
+		 * boosting the new task and new task will be donating importance to old task.
+		 */
+		inherit = ipc_importance_exec_switch_task(old_task, new_task);
+	}
+
+	kauth_cred_unref(&context.vc_ucred);
+
+	/* Image not claimed by any activator? */
+	if (error == -1) {
+		error = ENOEXEC;
+	}
+
+	if (!error) {
+		exec_done = TRUE;
+		assert(imgp->ip_new_thread != NULL);
+
+		exec_resettextvp(p, imgp);
+		error = check_for_signature(p, imgp);
+	}
+
+	/* flag exec has occurred, notify only if it has not failed due to FP Key error */
+	if (exec_done && ((p->p_lflag & P_LTERM_DECRYPTFAIL) == 0)) {
+		proc_knote(p, NOTE_EXEC);
+	}
+
+	if (imgp->ip_vp != NULLVP) {
+		vnode_put(imgp->ip_vp);
+	}
+	if (imgp->ip_scriptvp != NULLVP) {
+		vnode_put(imgp->ip_scriptvp);
+	}
+	if (imgp->ip_strings) {
+		execargs_free(imgp);
+	}
+#if CONFIG_MACF
+	if (imgp->ip_execlabelp) {
+		mac_cred_label_free(imgp->ip_execlabelp);
+	}
+	if (imgp->ip_scriptlabelp) {
+		mac_vnode_label_free(imgp->ip_scriptlabelp);
+	}
+#endif
+	if (imgp->ip_cs_error != OS_REASON_NULL) {
+		os_reason_free(imgp->ip_cs_error);
+		imgp->ip_cs_error = OS_REASON_NULL;
+	}
+
+	if (!error) {
+		/*
+		 * We need to initialize the bank context behind the protection of
+		 * the proc_trans lock to prevent a race with exit. We can't do this during
+		 * exec_activate_image because task_bank_init checks entitlements that
+		 * aren't loaded until subsequent calls (including exec_resettextvp).
+		 */
+		error = proc_transstart(p, 0, 0);
+	}
+
+	if (!error) {
+		task_bank_init(new_task);
+		proc_transend(p, 0);
+
+#if __arm64__
+		proc_legacy_footprint_entitled(p, new_task, __FUNCTION__);
+#endif /* __arm64__ */
+
+		/* Sever any extant thread affinity */
+		thread_affinity_exec(current_thread());
+
+		/* Inherit task role from old task to new task for exec */
+		if (!in_vfexec) {
+			proc_inherit_task_role(new_task, old_task);
+		}
+
+		thread_t main_thread = imgp->ip_new_thread;
+
+		task_set_main_thread_qos(new_task, main_thread);
+
+#if CONFIG_ARCADE
+		/*
+		 * Check to see if we need to trigger an arcade upcall AST now
+		 * that the vnode has been reset on the task.
+		 */
+		arcade_prepare(new_task, imgp->ip_new_thread);
+#endif /* CONFIG_ARCADE */
+
+#if CONFIG_MACF
+		/*
+		 * Processes with the MAP_JIT entitlement are permitted to have
+		 * a jumbo-size map.
+		 */
+		if (mac_proc_check_map_anon(p, 0, 0, 0, MAP_JIT, NULL) == 0) {
+			vm_map_set_jumbo(get_task_map(new_task));
+			vm_map_set_jit_entitled(get_task_map(new_task));
+		}
+#endif /* CONFIG_MACF */
+
+		if (vm_darkwake_mode == TRUE) {
+			/*
+			 * This process is being launched when the system
+			 * is in darkwake. So mark it specially. This will
+			 * cause all its pages to be entered in the background Q.
+			 */
+			task_set_darkwake_mode(new_task, vm_darkwake_mode);
+		}
+
+#if CONFIG_DTRACE
+		dtrace_thread_didexec(imgp->ip_new_thread);
+
+		if ((dtrace_proc_waitfor_hook = dtrace_proc_waitfor_exec_ptr) != NULL) {
+			(*dtrace_proc_waitfor_hook)(p);
+		}
+#endif
+
+#if CONFIG_AUDIT
+		if (!error && AUDIT_ENABLED() && p) {
+			/* Add the CDHash of the new process to the audit record */
+			uint8_t *cdhash = cs_get_cdhash(p);
+			if (cdhash) {
+				AUDIT_ARG(data, cdhash, sizeof(uint8_t), CS_CDHASH_LEN);
+			}
+		}
+#endif
+
+		if (in_vfexec) {
+			vfork_return(p, retval, p->p_pid);
+		}
+	} else {
+		DTRACE_PROC1(exec__failure, int, error);
+	}
+
+exit_with_error:
+
+	/*
+	 * clear bsd_info from old task if it did exec.
+	 */
+	if (task_did_exec(old_task)) {
+		set_bsdtask_info(old_task, NULL);
+	}
+
+	/* clear bsd_info from new task and terminate it if exec failed  */
+	if (new_task != NULL && task_is_exec_copy(new_task)) {
+		set_bsdtask_info(new_task, NULL);
+		task_terminate_internal(new_task);
+	}
+
+	if (imgp != NULL) {
+		/* Clear the initial wait on the thread transferring watchports */
+		if (imgp->ip_new_thread) {
+			task_clear_return_wait(get_threadtask(imgp->ip_new_thread), TCRW_CLEAR_INITIAL_WAIT);
+		}
+
+		/* Transfer the watchport boost to new task */
+		if (!error && !in_vfexec) {
+			task_transfer_turnstile_watchports(old_task,
+			    new_task, imgp->ip_new_thread);
+		}
+		/*
+		 * Do not terminate the current task, if proc_exec_switch_task did not
+		 * switch the tasks, terminating the current task without the switch would
+		 * result in loosing the SIGKILL status.
+		 */
+		if (task_did_exec(old_task)) {
+			/* Terminate the current task, since exec will start in new task */
+			task_terminate_internal(old_task);
+		}
+
+		/* Release the thread ref returned by fork_create_child */
+		if (imgp->ip_new_thread) {
+			/* wake up the new exec thread */
+			task_clear_return_wait(get_threadtask(imgp->ip_new_thread), TCRW_CLEAR_FINAL_WAIT);
+			thread_deallocate(imgp->ip_new_thread);
+			imgp->ip_new_thread = NULL;
+		}
+	}
+
+	/* Release the ref returned by fork_create_child */
+	if (new_task) {
+		task_deallocate(new_task);
+		new_task = NULL;
+	}
+
+	if (should_release_proc_ref) {
+		proc_rele(p);
+	}
+
+	if (bufp != NULL) {
+		FREE(bufp, M_TEMP);
+	}
+
+	if (inherit != NULL) {
+		ipc_importance_release(inherit);
+	}
+
+	return error;
+}
+
+
+/*
+ * copyinptr
+ *
+ * Description:	Copy a pointer in from user space to a user_addr_t in kernel
+ *		space, based on 32/64 bitness of the user space
+ *
+ * Parameters:	froma			User space address
+ *		toptr			Address of kernel space user_addr_t
+ *		ptr_size		4/8, based on 'froma' address space
+ *
+ * Returns:	0			Success
+ *		EFAULT			Bad 'froma'
+ *
+ * Implicit returns:
+ *		*ptr_size		Modified
+ */
+static int
+copyinptr(user_addr_t froma, user_addr_t *toptr, int ptr_size)
+{
+	int error;
+
+	if (ptr_size == 4) {
+		/* 64 bit value containing 32 bit address */
+		unsigned int i = 0;
+
+		error = copyin(froma, &i, 4);
+		*toptr = CAST_USER_ADDR_T(i);   /* SAFE */
+	} else {
+		error = copyin(froma, toptr, 8);
+	}
+	return error;
+}
+
+
+/*
+ * copyoutptr
+ *
+ * Description:	Copy a pointer out from a user_addr_t in kernel space to
+ *		user space, based on 32/64 bitness of the user space
+ *
+ * Parameters:	ua			User space address to copy to
+ *		ptr			Address of kernel space user_addr_t
+ *		ptr_size		4/8, based on 'ua' address space
+ *
+ * Returns:	0			Success
+ *		EFAULT			Bad 'ua'
+ *
+ */
+static int
+copyoutptr(user_addr_t ua, user_addr_t ptr, int ptr_size)
+{
+	int error;
+
+	if (ptr_size == 4) {
+		/* 64 bit value containing 32 bit address */
+		unsigned int i = CAST_DOWN_EXPLICIT(unsigned int, ua);   /* SAFE */
+
+		error = copyout(&i, ptr, 4);
+	} else {
+		error = copyout(&ua, ptr, 8);
+	}
+	return error;
+}
+
+
+/*
+ * exec_copyout_strings
+ *
+ * Copy out the strings segment to user space.  The strings segment is put
+ * on a preinitialized stack frame.
+ *
+ * Parameters:	struct image_params *	the image parameter block
+ *		int *			a pointer to the stack offset variable
+ *
+ * Returns:	0			Success
+ *		!0			Faiure: errno
+ *
+ * Implicit returns:
+ *		(*stackp)		The stack offset, modified
+ *
+ * Note:	The strings segment layout is backward, from the beginning
+ *		of the top of the stack to consume the minimal amount of
+ *		space possible; the returned stack pointer points to the
+ *		end of the area consumed (stacks grow downward).
+ *
+ *		argc is an int; arg[i] are pointers; env[i] are pointers;
+ *		the 0's are (void *)NULL's
+ *
+ * The stack frame layout is:
+ *
+ *      +-------------+ <- p->user_stack
+ *      |     16b     |
+ *      +-------------+
+ *      | STRING AREA |
+ *      |      :      |
+ *      |      :      |
+ *      |      :      |
+ *      +- -- -- -- --+
+ *      |  PATH AREA  |
+ *      +-------------+
+ *      |      0      |
+ *      +-------------+
+ *      |  applev[n]  |
+ *      +-------------+
+ *             :
+ *             :
+ *      +-------------+
+ *      |  applev[1]  |
+ *      +-------------+
+ *      | exec_path / |
+ *      |  applev[0]  |
+ *      +-------------+
+ *      |      0      |
+ *      +-------------+
+ *      |    env[n]   |
+ *      +-------------+
+ *             :
+ *             :
+ *      +-------------+
+ *      |    env[0]   |
+ *      +-------------+
+ *      |      0      |
+ *      +-------------+
+ *      | arg[argc-1] |
+ *      +-------------+
+ *             :
+ *             :
+ *      +-------------+
+ *      |    arg[0]   |
+ *      +-------------+
+ *      |     argc    |
+ * sp-> +-------------+
+ *
+ * Although technically a part of the STRING AREA, we treat the PATH AREA as
+ * a separate entity.  This allows us to align the beginning of the PATH AREA
+ * to a pointer boundary so that the exec_path, env[i], and argv[i] pointers
+ * which preceed it on the stack are properly aligned.
+ */
+
+static int
+exec_copyout_strings(struct image_params *imgp, user_addr_t *stackp)
+{
+	proc_t p = vfs_context_proc(imgp->ip_vfs_context);
+	int     ptr_size = (imgp->ip_flags & IMGPF_IS_64BIT_ADDR) ? 8 : 4;
+	int     ptr_area_size;
+	void *ptr_buffer_start, *ptr_buffer;
+	int string_size;
+
+	user_addr_t     string_area;    /* *argv[], *env[] */
+	user_addr_t     ptr_area;       /* argv[], env[], applev[] */
+	user_addr_t argc_area;  /* argc */
+	user_addr_t     stack;
+	int error;
+
+	unsigned i;
+	struct copyout_desc {
+		char    *start_string;
+		int             count;
+#if CONFIG_DTRACE
+		user_addr_t     *dtrace_cookie;
+#endif
+		boolean_t       null_term;
+	} descriptors[] = {
+		{
+			.start_string = imgp->ip_startargv,
+			.count = imgp->ip_argc,
+#if CONFIG_DTRACE
+			.dtrace_cookie = &p->p_dtrace_argv,
+#endif
+			.null_term = TRUE
+		},
+		{
+			.start_string = imgp->ip_endargv,
+			.count = imgp->ip_envc,
+#if CONFIG_DTRACE
+			.dtrace_cookie = &p->p_dtrace_envp,
+#endif
+			.null_term = TRUE
+		},
+		{
+			.start_string = imgp->ip_strings,
+			.count = 1,
+#if CONFIG_DTRACE
+			.dtrace_cookie = NULL,
+#endif
+			.null_term = FALSE
+		},
+		{
+			.start_string = imgp->ip_endenvv,
+			.count = imgp->ip_applec - 1, /* exec_path handled above */
+#if CONFIG_DTRACE
+			.dtrace_cookie = NULL,
+#endif
+			.null_term = TRUE
+		}
+	};
+
+	stack = *stackp;
+
+	/*
+	 * All previous contributors to the string area
+	 * should have aligned their sub-area
+	 */
+	if (imgp->ip_strspace % ptr_size != 0) {
+		error = EINVAL;
+		goto bad;
+	}
+
+	/* Grow the stack down for the strings we've been building up */
+	string_size = imgp->ip_strendp - imgp->ip_strings;
+	stack -= string_size;
+	string_area = stack;
+
+	/*
+	 * Need room for one pointer for each string, plus
+	 * one for the NULLs terminating the argv, envv, and apple areas.
+	 */
+	ptr_area_size = (imgp->ip_argc + imgp->ip_envc + imgp->ip_applec + 3) * ptr_size;
+	stack -= ptr_area_size;
+	ptr_area = stack;
+
+	/* We'll construct all the pointer arrays in our string buffer,
+	 * which we already know is aligned properly, and ip_argspace
+	 * was used to verify we have enough space.
+	 */
+	ptr_buffer_start = ptr_buffer = (void *)imgp->ip_strendp;
+
+	/*
+	 * Need room for pointer-aligned argc slot.
+	 */
+	stack -= ptr_size;
+	argc_area = stack;
+
+	/*
+	 * Record the size of the arguments area so that sysctl_procargs()
+	 * can return the argument area without having to parse the arguments.
+	 */
+	proc_lock(p);
+	p->p_argc = imgp->ip_argc;
+	p->p_argslen = (int)(*stackp - string_area);
+	proc_unlock(p);
+
+	/* Return the initial stack address: the location of argc */
+	*stackp = stack;
+
+	/*
+	 * Copy out the entire strings area.
+	 */
+	error = copyout(imgp->ip_strings, string_area,
+	    string_size);
+	if (error) {
+		goto bad;
+	}
+
+	for (i = 0; i < sizeof(descriptors) / sizeof(descriptors[0]); i++) {
+		char *cur_string = descriptors[i].start_string;
+		int j;
+
+#if CONFIG_DTRACE
+		if (descriptors[i].dtrace_cookie) {
+			proc_lock(p);
+			*descriptors[i].dtrace_cookie = ptr_area + ((uintptr_t)ptr_buffer - (uintptr_t)ptr_buffer_start); /* dtrace convenience */
+			proc_unlock(p);
+		}
+#endif /* CONFIG_DTRACE */
+
+		/*
+		 * For each segment (argv, envv, applev), copy as many pointers as requested
+		 * to our pointer buffer.
+		 */
+		for (j = 0; j < descriptors[i].count; j++) {
+			user_addr_t cur_address = string_area + (cur_string - imgp->ip_strings);
+
+			/* Copy out the pointer to the current string. Alignment has been verified  */
+			if (ptr_size == 8) {
+				*(uint64_t *)ptr_buffer = (uint64_t)cur_address;
+			} else {
+				*(uint32_t *)ptr_buffer = (uint32_t)cur_address;
+			}
+
+			ptr_buffer = (void *)((uintptr_t)ptr_buffer + ptr_size);
+			cur_string += strlen(cur_string) + 1; /* Only a NUL between strings in the same area */
+		}
+
+		if (descriptors[i].null_term) {
+			if (ptr_size == 8) {
+				*(uint64_t *)ptr_buffer = 0ULL;
+			} else {
+				*(uint32_t *)ptr_buffer = 0;
+			}
+
+			ptr_buffer = (void *)((uintptr_t)ptr_buffer + ptr_size);
+		}
+	}
+
+	/*
+	 * Copy out all our pointer arrays in bulk.
+	 */
+	error = copyout(ptr_buffer_start, ptr_area,
+	    ptr_area_size);
+	if (error) {
+		goto bad;
+	}
+
+	/* argc (int32, stored in a ptr_size area) */
+	error = copyoutptr((user_addr_t)imgp->ip_argc, argc_area, ptr_size);
+	if (error) {
+		goto bad;
+	}
+
+bad:
+	return error;
+}
+
+
+/*
+ * exec_extract_strings
+ *
+ * Copy arguments and environment from user space into work area; we may
+ * have already copied some early arguments into the work area, and if
+ * so, any arguments opied in are appended to those already there.
+ * This function is the primary manipulator of ip_argspace, since
+ * these are the arguments the client of execve(2) knows about. After
+ * each argv[]/envv[] string is copied, we charge the string length
+ * and argv[]/envv[] pointer slot to ip_argspace, so that we can
+ * full preflight the arg list size.
+ *
+ * Parameters:	struct image_params *	the image parameter block
+ *
+ * Returns:	0			Success
+ *		!0			Failure: errno
+ *
+ * Implicit returns;
+ *		(imgp->ip_argc)		Count of arguments, updated
+ *		(imgp->ip_envc)		Count of environment strings, updated
+ *		(imgp->ip_argspace)	Count of remaining of NCARGS
+ *		(imgp->ip_interp_buffer)	Interpreter and args (mutated in place)
+ *
+ *
+ * Note:	The argument and environment vectors are user space pointers
+ *		to arrays of user space pointers.
+ */
+static int
+exec_extract_strings(struct image_params *imgp)
+{
+	int error = 0;
+	int     ptr_size = (imgp->ip_flags & IMGPF_WAS_64BIT_ADDR) ? 8 : 4;
+	int new_ptr_size = (imgp->ip_flags & IMGPF_IS_64BIT_ADDR) ? 8 : 4;
+	user_addr_t     argv = imgp->ip_user_argv;
+	user_addr_t     envv = imgp->ip_user_envv;
+
+	/*
+	 * Adjust space reserved for the path name by however much padding it
+	 * needs. Doing this here since we didn't know if this would be a 32-
+	 * or 64-bit process back in exec_save_path.
+	 */
+	while (imgp->ip_strspace % new_ptr_size != 0) {
+		*imgp->ip_strendp++ = '\0';
+		imgp->ip_strspace--;
+		/* imgp->ip_argspace--; not counted towards exec args total */
+	}
+
+	/*
+	 * From now on, we start attributing string space to ip_argspace
+	 */
+	imgp->ip_startargv = imgp->ip_strendp;
+	imgp->ip_argc = 0;
+
+	if ((imgp->ip_flags & IMGPF_INTERPRET) != 0) {
+		user_addr_t     arg;
+		char *argstart, *ch;
+
+		/* First, the arguments in the "#!" string are tokenized and extracted. */
+		argstart = imgp->ip_interp_buffer;
+		while (argstart) {
+			ch = argstart;
+			while (*ch && !IS_WHITESPACE(*ch)) {
+				ch++;
+			}
+
+			if (*ch == '\0') {
+				/* last argument, no need to NUL-terminate */
+				error = exec_add_user_string(imgp, CAST_USER_ADDR_T(argstart), UIO_SYSSPACE, TRUE);
+				argstart = NULL;
+			} else {
+				/* NUL-terminate */
+				*ch = '\0';
+				error = exec_add_user_string(imgp, CAST_USER_ADDR_T(argstart), UIO_SYSSPACE, TRUE);
+
+				/*
+				 * Find the next string. We know spaces at the end of the string have already
+				 * been stripped.
+				 */
+				argstart = ch + 1;
+				while (IS_WHITESPACE(*argstart)) {
+					argstart++;
+				}
+			}
+
+			/* Error-check, regardless of whether this is the last interpreter arg or not */
+			if (error) {
+				goto bad;
+			}
+			if (imgp->ip_argspace < new_ptr_size) {
+				error = E2BIG;
+				goto bad;
+			}
+			imgp->ip_argspace -= new_ptr_size; /* to hold argv[] entry */
+			imgp->ip_argc++;
+		}
+
+		if (argv != 0LL) {
+			/*
+			 * If we are running an interpreter, replace the av[0] that was
+			 * passed to execve() with the path name that was
+			 * passed to execve() for interpreters which do not use the PATH
+			 * to locate their script arguments.
+			 */
+			error = copyinptr(argv, &arg, ptr_size);
+			if (error) {
+				goto bad;
+			}
+			if (arg != 0LL) {
+				argv += ptr_size; /* consume without using */
+			}
+		}
+
+		if (imgp->ip_interp_sugid_fd != -1) {
+			char temp[19]; /* "/dev/fd/" + 10 digits + NUL */
+			snprintf(temp, sizeof(temp), "/dev/fd/%d", imgp->ip_interp_sugid_fd);
+			error = exec_add_user_string(imgp, CAST_USER_ADDR_T(temp), UIO_SYSSPACE, TRUE);
+		} else {
+			error = exec_add_user_string(imgp, imgp->ip_user_fname, imgp->ip_seg, TRUE);
+		}
+
+		if (error) {
+			goto bad;
+		}
+		if (imgp->ip_argspace < new_ptr_size) {
+			error = E2BIG;
+			goto bad;
+		}
+		imgp->ip_argspace -= new_ptr_size; /* to hold argv[] entry */
+		imgp->ip_argc++;
+	}
+
+	while (argv != 0LL) {
+		user_addr_t     arg;
+
+		error = copyinptr(argv, &arg, ptr_size);
+		if (error) {
+			goto bad;
+		}
+
+		if (arg == 0LL) {
+			break;
+		}
+
+		argv += ptr_size;
+
+		/*
+		 * av[n...] = arg[n]
+		 */
+		error = exec_add_user_string(imgp, arg, imgp->ip_seg, TRUE);
+		if (error) {
+			goto bad;
+		}
+		if (imgp->ip_argspace < new_ptr_size) {
+			error = E2BIG;
+			goto bad;
+		}
+		imgp->ip_argspace -= new_ptr_size; /* to hold argv[] entry */
+		imgp->ip_argc++;
+	}
+
+	/* Save space for argv[] NULL terminator */
+	if (imgp->ip_argspace < new_ptr_size) {
+		error = E2BIG;
+		goto bad;
+	}
+	imgp->ip_argspace -= new_ptr_size;
+
+	/* Note where the args ends and env begins. */
+	imgp->ip_endargv = imgp->ip_strendp;
+	imgp->ip_envc = 0;
+
+	/* Now, get the environment */
+	while (envv != 0LL) {
+		user_addr_t     env;
+
+		error = copyinptr(envv, &env, ptr_size);
+		if (error) {
+			goto bad;
+		}
+
+		envv += ptr_size;
+		if (env == 0LL) {
+			break;
+		}
+		/*
+		 * av[n...] = env[n]
+		 */
+		error = exec_add_user_string(imgp, env, imgp->ip_seg, TRUE);
+		if (error) {
+			goto bad;
+		}
+		if (imgp->ip_argspace < new_ptr_size) {
+			error = E2BIG;
+			goto bad;
+		}
+		imgp->ip_argspace -= new_ptr_size; /* to hold envv[] entry */
+		imgp->ip_envc++;
+	}
+
+	/* Save space for envv[] NULL terminator */
+	if (imgp->ip_argspace < new_ptr_size) {
+		error = E2BIG;
+		goto bad;
+	}
+	imgp->ip_argspace -= new_ptr_size;
+
+	/* Align the tail of the combined argv+envv area */
+	while (imgp->ip_strspace % new_ptr_size != 0) {
+		if (imgp->ip_argspace < 1) {
+			error = E2BIG;
+			goto bad;
+		}
+		*imgp->ip_strendp++ = '\0';
+		imgp->ip_strspace--;
+		imgp->ip_argspace--;
+	}
+
+	/* Note where the envv ends and applev begins. */
+	imgp->ip_endenvv = imgp->ip_strendp;
+
+	/*
+	 * From now on, we are no longer charging argument
+	 * space to ip_argspace.
+	 */
+
+bad:
+	return error;
+}
+
+/*
+ * Libc has an 8-element array set up for stack guard values.  It only fills
+ * in one of those entries, and both gcc and llvm seem to use only a single
+ * 8-byte guard.  Until somebody needs more than an 8-byte guard value, don't
+ * do the work to construct them.
+ */
+#define GUARD_VALUES 1
+#define GUARD_KEY "stack_guard="
+
+/*
+ * System malloc needs some entropy when it is initialized.
+ */
+#define ENTROPY_VALUES 2
+#define ENTROPY_KEY "malloc_entropy="
+
+/*
+ * libplatform needs a random pointer-obfuscation value when it is initialized.
+ */
+#define PTR_MUNGE_VALUES 1
+#define PTR_MUNGE_KEY "ptr_munge="
+
+/*
+ * System malloc engages nanozone for UIAPP.
+ */
+#define NANO_ENGAGE_KEY "MallocNanoZone=1"
+
+#define PFZ_KEY "pfz="
+extern user32_addr_t commpage_text32_location;
+extern user64_addr_t commpage_text64_location;
+
+#define MAIN_STACK_VALUES 4
+#define MAIN_STACK_KEY "main_stack="
+
+#define FSID_KEY "executable_file="
+#define DYLD_FSID_KEY "dyld_file="
+#define CDHASH_KEY "executable_cdhash="
+#define DYLD_FLAGS_KEY "dyld_flags="
+
+#define FSID_MAX_STRING "0x1234567890abcdef,0x1234567890abcdef"
+
+#define HEX_STR_LEN 18 // 64-bit hex value "0x0123456701234567"
+
+static int
+exec_add_entropy_key(struct image_params *imgp,
+    const char *key,
+    int values,
+    boolean_t embedNUL)
+{
+	const int limit = 8;
+	uint64_t entropy[limit];
+	char str[strlen(key) + (HEX_STR_LEN + 1) * limit + 1];
+	if (values > limit) {
+		values = limit;
+	}
+
+	read_random(entropy, sizeof(entropy[0]) * values);
+
+	if (embedNUL) {
+		entropy[0] &= ~(0xffull << 8);
+	}
+
+	int len = snprintf(str, sizeof(str), "%s0x%llx", key, entropy[0]);
+	int remaining = sizeof(str) - len;
+	for (int i = 1; i < values && remaining > 0; ++i) {
+		int start = sizeof(str) - remaining;
+		len = snprintf(&str[start], remaining, ",0x%llx", entropy[i]);
+		remaining -= len;
+	}
+
+	return exec_add_user_string(imgp, CAST_USER_ADDR_T(str), UIO_SYSSPACE, FALSE);
+}
+
+/*
+ * Build up the contents of the apple[] string vector
+ */
+#if (DEVELOPMENT || DEBUG)
+uint64_t dyld_flags = 0;
+#endif
+
+static int
+exec_add_apple_strings(struct image_params *imgp,
+    const load_result_t *load_result)
+{
+	int error;
+	int img_ptr_size = (imgp->ip_flags & IMGPF_IS_64BIT_ADDR) ? 8 : 4;
+
+	/* exec_save_path stored the first string */
+	imgp->ip_applec = 1;
+
+	/* adding the pfz string */
+	{
+		char pfz_string[strlen(PFZ_KEY) + HEX_STR_LEN + 1];
+
+		if (img_ptr_size == 8) {
+			snprintf(pfz_string, sizeof(pfz_string), PFZ_KEY "0x%llx", commpage_text64_location);
+		} else {
+			snprintf(pfz_string, sizeof(pfz_string), PFZ_KEY "0x%x", commpage_text32_location);
+		}
+		error = exec_add_user_string(imgp, CAST_USER_ADDR_T(pfz_string), UIO_SYSSPACE, FALSE);
+		if (error) {
+			goto bad;
+		}
+		imgp->ip_applec++;
+	}
+
+	/* adding the NANO_ENGAGE_KEY key */
+	if (imgp->ip_px_sa) {
+		int proc_flags = (((struct _posix_spawnattr *) imgp->ip_px_sa)->psa_flags);
+
+		if ((proc_flags & _POSIX_SPAWN_NANO_ALLOCATOR) == _POSIX_SPAWN_NANO_ALLOCATOR) {
+			const char *nano_string = NANO_ENGAGE_KEY;
+			error = exec_add_user_string(imgp, CAST_USER_ADDR_T(nano_string), UIO_SYSSPACE, FALSE);
+			if (error) {
+				goto bad;
+			}
+			imgp->ip_applec++;
+		}
+	}
+
+	/*
+	 * Supply libc with a collection of random values to use when
+	 * implementing -fstack-protector.
+	 *
+	 * (The first random string always contains an embedded NUL so that
+	 * __stack_chk_guard also protects against C string vulnerabilities)
+	 */
+	error = exec_add_entropy_key(imgp, GUARD_KEY, GUARD_VALUES, TRUE);
+	if (error) {
+		goto bad;
+	}
+	imgp->ip_applec++;
+
+	/*
+	 * Supply libc with entropy for system malloc.
+	 */
+	error = exec_add_entropy_key(imgp, ENTROPY_KEY, ENTROPY_VALUES, FALSE);
+	if (error) {
+		goto bad;
+	}
+	imgp->ip_applec++;
+
+	/*
+	 * Supply libpthread & libplatform with a random value to use for pointer
+	 * obfuscation.
+	 */
+	error = exec_add_entropy_key(imgp, PTR_MUNGE_KEY, PTR_MUNGE_VALUES, FALSE);
+	if (error) {
+		goto bad;
+	}
+	imgp->ip_applec++;
+
+	/*
+	 * Add MAIN_STACK_KEY: Supplies the address and size of the main thread's
+	 * stack if it was allocated by the kernel.
+	 *
+	 * The guard page is not included in this stack size as libpthread
+	 * expects to add it back in after receiving this value.
+	 */
+	if (load_result->unixproc) {
+		char stack_string[strlen(MAIN_STACK_KEY) + (HEX_STR_LEN + 1) * MAIN_STACK_VALUES + 1];
+		snprintf(stack_string, sizeof(stack_string),
+		    MAIN_STACK_KEY "0x%llx,0x%llx,0x%llx,0x%llx",
+		    (uint64_t)load_result->user_stack,
+		    (uint64_t)load_result->user_stack_size,
+		    (uint64_t)load_result->user_stack_alloc,
+		    (uint64_t)load_result->user_stack_alloc_size);
+		error = exec_add_user_string(imgp, CAST_USER_ADDR_T(stack_string), UIO_SYSSPACE, FALSE);
+		if (error) {
+			goto bad;
+		}
+		imgp->ip_applec++;
+	}
+
+	if (imgp->ip_vattr) {
+		uint64_t fsid    = vnode_get_va_fsid(imgp->ip_vattr);
+		uint64_t fsobjid = imgp->ip_vattr->va_fileid;
+
+		char fsid_string[strlen(FSID_KEY) + strlen(FSID_MAX_STRING) + 1];
+		snprintf(fsid_string, sizeof(fsid_string),
+		    FSID_KEY "0x%llx,0x%llx", fsid, fsobjid);
+		error = exec_add_user_string(imgp, CAST_USER_ADDR_T(fsid_string), UIO_SYSSPACE, FALSE);
+		if (error) {
+			goto bad;
+		}
+		imgp->ip_applec++;
+	}
+
+	if (imgp->ip_dyld_fsid || imgp->ip_dyld_fsobjid) {
+		char fsid_string[strlen(DYLD_FSID_KEY) + strlen(FSID_MAX_STRING) + 1];
+		snprintf(fsid_string, sizeof(fsid_string),
+		    DYLD_FSID_KEY "0x%llx,0x%llx", imgp->ip_dyld_fsid, imgp->ip_dyld_fsobjid);
+		error = exec_add_user_string(imgp, CAST_USER_ADDR_T(fsid_string), UIO_SYSSPACE, FALSE);
+		if (error) {
+			goto bad;
+		}
+		imgp->ip_applec++;
+	}
+
+	uint8_t cdhash[SHA1_RESULTLEN];
+	int cdhash_errror = ubc_cs_getcdhash(imgp->ip_vp, imgp->ip_arch_offset, cdhash);
+	if (cdhash_errror == 0) {
+		char hash_string[strlen(CDHASH_KEY) + 2 * SHA1_RESULTLEN + 1];
+		strncpy(hash_string, CDHASH_KEY, sizeof(hash_string));
+		char *p = hash_string + sizeof(CDHASH_KEY) - 1;
+		for (int i = 0; i < SHA1_RESULTLEN; i++) {
+			snprintf(p, 3, "%02x", (int) cdhash[i]);
+			p += 2;
+		}
+		error = exec_add_user_string(imgp, CAST_USER_ADDR_T(hash_string), UIO_SYSSPACE, FALSE);
+		if (error) {
+			goto bad;
+		}
+		imgp->ip_applec++;
+	}
+#if (DEVELOPMENT || DEBUG)
+	if (dyld_flags) {
+		char dyld_flags_string[strlen(DYLD_FLAGS_KEY) + HEX_STR_LEN + 1];
+		snprintf(dyld_flags_string, sizeof(dyld_flags_string), DYLD_FLAGS_KEY "0x%llx", dyld_flags);
+		error = exec_add_user_string(imgp, CAST_USER_ADDR_T(dyld_flags_string), UIO_SYSSPACE, FALSE);
+		if (error) {
+			goto bad;
+		}
+		imgp->ip_applec++;
+	}
+#endif
+
+	/* Align the tail of the combined applev area */
+	while (imgp->ip_strspace % img_ptr_size != 0) {
+		*imgp->ip_strendp++ = '\0';
+		imgp->ip_strspace--;
+	}
+
+bad:
+	return error;
+}
+
+#define unix_stack_size(p)      (p->p_rlimit[RLIMIT_STACK].rlim_cur)
+
+/*
+ * exec_check_permissions
+ *
+ * Description:	Verify that the file that is being attempted to be executed
+ *		is in fact allowed to be executed based on it POSIX file
+ *		permissions and other access control criteria
+ *
+ * Parameters:	struct image_params *	the image parameter block
+ *
+ * Returns:	0			Success
+ *		EACCES			Permission denied
+ *		ENOEXEC			Executable file format error
+ *		ETXTBSY			Text file busy [misuse of error code]
+ *	vnode_getattr:???
+ *	vnode_authorize:???
+ */
+static int
+exec_check_permissions(struct image_params *imgp)
+{
+	struct vnode *vp = imgp->ip_vp;
+	struct vnode_attr *vap = imgp->ip_vattr;
+	proc_t p = vfs_context_proc(imgp->ip_vfs_context);
+	int error;
+	kauth_action_t action;
+
+	/* Only allow execution of regular files */
+	if (!vnode_isreg(vp)) {
+		return EACCES;
+	}
+
+	/* Get the file attributes that we will be using here and elsewhere */
+	VATTR_INIT(vap);
+	VATTR_WANTED(vap, va_uid);
+	VATTR_WANTED(vap, va_gid);
+	VATTR_WANTED(vap, va_mode);
+	VATTR_WANTED(vap, va_fsid);
+	VATTR_WANTED(vap, va_fsid64);
+	VATTR_WANTED(vap, va_fileid);
+	VATTR_WANTED(vap, va_data_size);
+	if ((error = vnode_getattr(vp, vap, imgp->ip_vfs_context)) != 0) {
+		return error;
+	}
+
+	/*
+	 * Ensure that at least one execute bit is on - otherwise root
+	 * will always succeed, and we don't want to happen unless the
+	 * file really is executable.
+	 */
+	if (!vfs_authopaque(vnode_mount(vp)) && ((vap->va_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) == 0)) {
+		return EACCES;
+	}
+
+	/* Disallow zero length files */
+	if (vap->va_data_size == 0) {
+		return ENOEXEC;
+	}
+
+	imgp->ip_arch_offset = (user_size_t)0;
+	imgp->ip_arch_size = vap->va_data_size;
+
+	/* Disable setuid-ness for traced programs or if MNT_NOSUID */
+	if ((vp->v_mount->mnt_flag & MNT_NOSUID) || (p->p_lflag & P_LTRACED)) {
+		vap->va_mode &= ~(VSUID | VSGID);
+	}
+
+	/*
+	 * Disable _POSIX_SPAWN_ALLOW_DATA_EXEC and _POSIX_SPAWN_DISABLE_ASLR
+	 * flags for setuid/setgid binaries.
+	 */
+	if (vap->va_mode & (VSUID | VSGID)) {
+		imgp->ip_flags &= ~(IMGPF_ALLOW_DATA_EXEC | IMGPF_DISABLE_ASLR);
+	}
+
+#if CONFIG_MACF
+	error = mac_vnode_check_exec(imgp->ip_vfs_context, vp, imgp);
+	if (error) {
+		return error;
+	}
+#endif
+
+	/* Check for execute permission */
+	action = KAUTH_VNODE_EXECUTE;
+	/* Traced images must also be readable */
+	if (p->p_lflag & P_LTRACED) {
+		action |= KAUTH_VNODE_READ_DATA;
+	}
+	if ((error = vnode_authorize(vp, NULL, action, imgp->ip_vfs_context)) != 0) {
+		return error;
+	}
+
+#if 0
+	/* Don't let it run if anyone had it open for writing */
+	vnode_lock(vp);
+	if (vp->v_writecount) {
+		panic("going to return ETXTBSY %x", vp);
+		vnode_unlock(vp);
+		return ETXTBSY;
+	}
+	vnode_unlock(vp);
+#endif
+
+
+	/* XXX May want to indicate to underlying FS that vnode is open */
+
+	return error;
+}
+
+
+/*
+ * exec_handle_sugid
+ *
+ * Initially clear the P_SUGID in the process flags; if an SUGID process is
+ * exec'ing a non-SUGID image, then  this is the point of no return.
+ *
+ * If the image being activated is SUGID, then replace the credential with a
+ * copy, disable tracing (unless the tracing process is root), reset the
+ * mach task port to revoke it, set the P_SUGID bit,
+ *
+ * If the saved user and group ID will be changing, then make sure it happens
+ * to a new credential, rather than a shared one.
+ *
+ * Set the security token (this is probably obsolete, given that the token
+ * should not technically be separate from the credential itself).
+ *
+ * Parameters:	struct image_params *	the image parameter block
+ *
+ * Returns:	void			No failure indication
+ *
+ * Implicit returns:
+ *		<process credential>	Potentially modified/replaced
+ *		<task port>		Potentially revoked
+ *		<process flags>		P_SUGID bit potentially modified
+ *		<security token>	Potentially modified
+ */
+static int
+exec_handle_sugid(struct image_params *imgp)
+{
+	proc_t                  p = vfs_context_proc(imgp->ip_vfs_context);
+	kauth_cred_t            cred = vfs_context_ucred(imgp->ip_vfs_context);
+	int                     i;
+	int                     leave_sugid_clear = 0;
+	int                     mac_reset_ipc = 0;
+	int                     error = 0;
+	task_t                  task = NULL;
+#if CONFIG_MACF
+	int                     mac_transition, disjoint_cred = 0;
+	int             label_update_return = 0;
+
+	/*
+	 * Determine whether a call to update the MAC label will result in the
+	 * credential changing.
+	 *
+	 * Note:	MAC policies which do not actually end up modifying
+	 *		the label subsequently are strongly encouraged to
+	 *		return 0 for this check, since a non-zero answer will
+	 *		slow down the exec fast path for normal binaries.
+	 */
+	mac_transition = mac_cred_check_label_update_execve(
+		imgp->ip_vfs_context,
+		imgp->ip_vp,
+		imgp->ip_arch_offset,
+		imgp->ip_scriptvp,
+		imgp->ip_scriptlabelp,
+		imgp->ip_execlabelp,
+		p,
+		imgp->ip_px_smpx);
+#endif
+
+	OSBitAndAtomic(~((uint32_t)P_SUGID), &p->p_flag);
+
+	/*
+	 * Order of the following is important; group checks must go last,
+	 * as we use the success of the 'ismember' check combined with the
+	 * failure of the explicit match to indicate that we will be setting
+	 * the egid of the process even though the new process did not
+	 * require VSUID/VSGID bits in order for it to set the new group as
+	 * its egid.
+	 *
+	 * Note:	Technically, by this we are implying a call to
+	 *		setegid() in the new process, rather than implying
+	 *		it used its VSGID bit to set the effective group,
+	 *		even though there is no code in that process to make
+	 *		such a call.
+	 */
+	if (((imgp->ip_origvattr->va_mode & VSUID) != 0 &&
+	    kauth_cred_getuid(cred) != imgp->ip_origvattr->va_uid) ||
+	    ((imgp->ip_origvattr->va_mode & VSGID) != 0 &&
+	    ((kauth_cred_ismember_gid(cred, imgp->ip_origvattr->va_gid, &leave_sugid_clear) || !leave_sugid_clear) ||
+	    (kauth_cred_getgid(cred) != imgp->ip_origvattr->va_gid)))) {
+#if CONFIG_MACF
+/* label for MAC transition and neither VSUID nor VSGID */
+handle_mac_transition:
+#endif
+
+#if !SECURE_KERNEL
+		/*
+		 * Replace the credential with a copy of itself if euid or
+		 * egid change.
+		 *
+		 * Note:	setuid binaries will automatically opt out of
+		 *		group resolver participation as a side effect
+		 *		of this operation.  This is an intentional
+		 *		part of the security model, which requires a
+		 *		participating credential be established by
+		 *		escalating privilege, setting up all other
+		 *		aspects of the credential including whether
+		 *		or not to participate in external group
+		 *		membership resolution, then dropping their
+		 *		effective privilege to that of the desired
+		 *		final credential state.
+		 *
+		 * Modifications to p_ucred must be guarded using the
+		 * proc's ucred lock. This prevents others from accessing
+		 * a garbage credential.
+		 */
+		if (imgp->ip_origvattr->va_mode & VSUID) {
+			apply_kauth_cred_update(p, ^kauth_cred_t (kauth_cred_t my_cred) {
+				return kauth_cred_setresuid(my_cred,
+				KAUTH_UID_NONE,
+				imgp->ip_origvattr->va_uid,
+				imgp->ip_origvattr->va_uid,
+				KAUTH_UID_NONE);
+			});
+		}
+
+		if (imgp->ip_origvattr->va_mode & VSGID) {
+			apply_kauth_cred_update(p, ^kauth_cred_t (kauth_cred_t my_cred) {
+				return kauth_cred_setresgid(my_cred,
+				KAUTH_GID_NONE,
+				imgp->ip_origvattr->va_gid,
+				imgp->ip_origvattr->va_gid);
+			});
+		}
+#endif /* !SECURE_KERNEL */
+
+#if CONFIG_MACF
+		/*
+		 * If a policy has indicated that it will transition the label,
+		 * before making the call into the MAC policies, get a new
+		 * duplicate credential, so they can modify it without
+		 * modifying any others sharing it.
+		 */
+		if (mac_transition) {
+			/*
+			 * This hook may generate upcalls that require
+			 * importance donation from the kernel.
+			 * (23925818)
+			 */
+			thread_t thread = current_thread();
+			thread_enable_send_importance(thread, TRUE);
+			kauth_proc_label_update_execve(p,
+			    imgp->ip_vfs_context,
+			    imgp->ip_vp,
+			    imgp->ip_arch_offset,
+			    imgp->ip_scriptvp,
+			    imgp->ip_scriptlabelp,
+			    imgp->ip_execlabelp,
+			    &imgp->ip_csflags,
+			    imgp->ip_px_smpx,
+			    &disjoint_cred,                     /* will be non zero if disjoint */
+			    &label_update_return);
+			thread_enable_send_importance(thread, FALSE);
+
+			if (disjoint_cred) {
+				/*
+				 * If updating the MAC label resulted in a
+				 * disjoint credential, flag that we need to
+				 * set the P_SUGID bit.  This protects
+				 * against debuggers being attached by an
+				 * insufficiently privileged process onto the
+				 * result of a transition to a more privileged
+				 * credential.
+				 */
+				leave_sugid_clear = 0;
+			}
+
+			imgp->ip_mac_return = label_update_return;
+		}
+
+		mac_reset_ipc = mac_proc_check_inherit_ipc_ports(p, p->p_textvp, p->p_textoff, imgp->ip_vp, imgp->ip_arch_offset, imgp->ip_scriptvp);
+
+#endif  /* CONFIG_MACF */
+
+		/*
+		 * If 'leave_sugid_clear' is non-zero, then we passed the
+		 * VSUID and MACF checks, and successfully determined that
+		 * the previous cred was a member of the VSGID group, but
+		 * that it was not the default at the time of the execve,
+		 * and that the post-labelling credential was not disjoint.
+		 * So we don't set the P_SUGID or reset mach ports and fds
+		 * on the basis of simply running this code.
+		 */
+		if (mac_reset_ipc || !leave_sugid_clear) {
+			/*
+			 * Have mach reset the task and thread ports.
+			 * We don't want anyone who had the ports before
+			 * a setuid exec to be able to access/control the
+			 * task/thread after.
+			 */
+			ipc_task_reset((imgp->ip_new_thread != NULL) ?
+			    get_threadtask(imgp->ip_new_thread) : p->task);
+			ipc_thread_reset((imgp->ip_new_thread != NULL) ?
+			    imgp->ip_new_thread : current_thread());
+		}
+
+		if (!leave_sugid_clear) {
+			/*
+			 * Flag the process as setuid.
+			 */
+			OSBitOrAtomic(P_SUGID, &p->p_flag);
+
+			/*
+			 * Radar 2261856; setuid security hole fix
+			 * XXX For setuid processes, attempt to ensure that
+			 * stdin, stdout, and stderr are already allocated.
+			 * We do not want userland to accidentally allocate
+			 * descriptors in this range which has implied meaning
+			 * to libc.
+			 */
+			for (i = 0; i < 3; i++) {
+				if (p->p_fd->fd_ofiles[i] != NULL) {
+					continue;
+				}
+
+				/*
+				 * Do the kernel equivalent of
+				 *
+				 *      if i == 0
+				 *              (void) open("/dev/null", O_RDONLY);
+				 *      else
+				 *              (void) open("/dev/null", O_WRONLY);
+				 */
+
+				struct fileproc *fp;
+				int indx;
+				int flag;
+				struct nameidata *ndp = NULL;
+
+				if (i == 0) {
+					flag = FREAD;
+				} else {
+					flag = FWRITE;
+				}
+
+				if ((error = falloc(p,
+				    &fp, &indx, imgp->ip_vfs_context)) != 0) {
+					continue;
+				}
+
+				MALLOC(ndp, struct nameidata *, sizeof(*ndp), M_TEMP, M_WAITOK | M_ZERO);
+				if (ndp == NULL) {
+					fp_free(p, indx, fp);
+					error = ENOMEM;
+					break;
+				}
+
+				NDINIT(ndp, LOOKUP, OP_OPEN, FOLLOW, UIO_SYSSPACE,
+				    CAST_USER_ADDR_T("/dev/null"),
+				    imgp->ip_vfs_context);
+
+				if ((error = vn_open(ndp, flag, 0)) != 0) {
+					fp_free(p, indx, fp);
+					FREE(ndp, M_TEMP);
+					break;
+				}
+
+				struct fileglob *fg = fp->f_fglob;
+
+				fg->fg_flag = flag;
+				fg->fg_ops = &vnops;
+				fg->fg_data = ndp->ni_vp;
+
+				vnode_put(ndp->ni_vp);
+
+				proc_fdlock(p);
+				procfdtbl_releasefd(p, indx, NULL);
+				fp_drop(p, indx, fp, 1);
+				proc_fdunlock(p);
+
+				FREE(ndp, M_TEMP);
+			}
+		}
+	}
+#if CONFIG_MACF
+	else {
+		/*
+		 * We are here because we were told that the MAC label will
+		 * be transitioned, and the binary is not VSUID or VSGID; to
+		 * deal with this case, we could either duplicate a lot of
+		 * code, or we can indicate we want to default the P_SUGID
+		 * bit clear and jump back up.
+		 */
+		if (mac_transition) {
+			leave_sugid_clear = 1;
+			goto handle_mac_transition;
+		}
+	}
+
+#endif  /* CONFIG_MACF */
+
+	/*
+	 * Implement the semantic where the effective user and group become
+	 * the saved user and group in exec'ed programs.
+	 *
+	 * Modifications to p_ucred must be guarded using the
+	 * proc's ucred lock. This prevents others from accessing
+	 * a garbage credential.
+	 */
+	apply_kauth_cred_update(p, ^kauth_cred_t (kauth_cred_t my_cred) {
+		return kauth_cred_setsvuidgid(my_cred,
+		kauth_cred_getuid(my_cred),
+		kauth_cred_getgid(my_cred));
+	});
+
+	/* Update the process' identity version and set the security token */
+	p->p_idversion = OSIncrementAtomic(&nextpidversion);
+
+	if (imgp->ip_new_thread != NULL) {
+		task = get_threadtask(imgp->ip_new_thread);
+	} else {
+		task = p->task;
+	}
+	set_security_token_task_internal(p, task);
+
+	return error;
+}
+
+
+/*
+ * create_unix_stack
+ *
+ * Description:	Set the user stack address for the process to the provided
+ *		address.  If a custom stack was not set as a result of the
+ *		load process (i.e. as specified by the image file for the
+ *		executable), then allocate the stack in the provided map and
+ *		set up appropriate guard pages for enforcing administrative
+ *		limits on stack growth, if they end up being needed.
+ *
+ * Parameters:	p			Process to set stack on
+ *		load_result		Information from mach-o load commands
+ *		map			Address map in which to allocate the new stack
+ *
+ * Returns:	KERN_SUCCESS		Stack successfully created
+ *		!KERN_SUCCESS		Mach failure code
+ */
+static kern_return_t
+create_unix_stack(vm_map_t map, load_result_t* load_result,
+    proc_t p)
+{
+	mach_vm_size_t          size, prot_size;
+	mach_vm_offset_t        addr, prot_addr;
+	kern_return_t           kr;
+
+	mach_vm_address_t       user_stack = load_result->user_stack;
+
+	proc_lock(p);
+	p->user_stack = user_stack;
+	if (load_result->custom_stack) {
+		p->p_lflag |= P_LCUSTOM_STACK;
+	}
+	proc_unlock(p);
+
+	if (load_result->user_stack_alloc_size > 0) {
+		/*
+		 * Allocate enough space for the maximum stack size we
+		 * will ever authorize and an extra page to act as
+		 * a guard page for stack overflows. For default stacks,
+		 * vm_initial_limit_stack takes care of the extra guard page.
+		 * Otherwise we must allocate it ourselves.
+		 */
+		if (mach_vm_round_page_overflow(load_result->user_stack_alloc_size, &size)) {
+			return KERN_INVALID_ARGUMENT;
+		}
+		addr = mach_vm_trunc_page(load_result->user_stack - size);
+		kr = mach_vm_allocate_kernel(map, &addr, size,
+		    VM_FLAGS_FIXED, VM_MEMORY_STACK);
+		if (kr != KERN_SUCCESS) {
+			// Can't allocate at default location, try anywhere
+			addr = 0;
+			kr = mach_vm_allocate_kernel(map, &addr, size,
+			    VM_FLAGS_ANYWHERE, VM_MEMORY_STACK);
+			if (kr != KERN_SUCCESS) {
+				return kr;
+			}
+
+			user_stack = addr + size;
+			load_result->user_stack = user_stack;
+
+			proc_lock(p);
+			p->user_stack = user_stack;
+			proc_unlock(p);
+		}
+
+		load_result->user_stack_alloc = addr;
+
+		/*
+		 * And prevent access to what's above the current stack
+		 * size limit for this process.
+		 */
+		if (load_result->user_stack_size == 0) {
+			proc_list_lock();
+			load_result->user_stack_size = unix_stack_size(p);
+			proc_list_unlock();
+			prot_size = mach_vm_trunc_page(size - load_result->user_stack_size);
+		} else {
+			prot_size = PAGE_SIZE;
+		}
+
+		prot_addr = addr;
+		kr = mach_vm_protect(map,
+		    prot_addr,
+		    prot_size,
+		    FALSE,
+		    VM_PROT_NONE);
+		if (kr != KERN_SUCCESS) {
+			(void)mach_vm_deallocate(map, addr, size);
+			return kr;
+		}
+	}
+
+	return KERN_SUCCESS;
+}
+
+#include <sys/reboot.h>
+
+/*
+ * load_init_program_at_path
+ *
+ * Description:	Load the "init" program; in most cases, this will be "launchd"
+ *
+ * Parameters:	p			Process to call execve() to create
+ *					the "init" program
+ *		scratch_addr		Page in p, scratch space
+ *		path			NULL terminated path
+ *
+ * Returns:	KERN_SUCCESS		Success
+ *		!KERN_SUCCESS           See execve/mac_execve for error codes
+ *
+ * Notes:	The process that is passed in is the first manufactured
+ *		process on the system, and gets here via bsd_ast() firing
+ *		for the first time.  This is done to ensure that bsd_init()
+ *		has run to completion.
+ *
+ *		The address map of the first manufactured process matches the
+ *		word width of the kernel. Once the self-exec completes, the
+ *		initproc might be different.
+ */
+static int
+load_init_program_at_path(proc_t p, user_addr_t scratch_addr, const char* path)
+{
+	int retval[2];
+	int error;
+	struct execve_args init_exec_args;
+	user_addr_t argv0 = USER_ADDR_NULL, argv1 = USER_ADDR_NULL;
+
+	/*
+	 * Validate inputs and pre-conditions
+	 */
+	assert(p);
+	assert(scratch_addr);
+	assert(path);
+
+	/*
+	 * Copy out program name.
+	 */
+	size_t path_length = strlen(path) + 1;
+	argv0 = scratch_addr;
+	error = copyout(path, argv0, path_length);
+	if (error) {
+		return error;
+	}
+
+	scratch_addr = USER_ADDR_ALIGN(scratch_addr + path_length, sizeof(user_addr_t));
+
+	/*
+	 * Put out first (and only) argument, similarly.
+	 * Assumes everything fits in a page as allocated above.
+	 */
+	if (boothowto & RB_SINGLE) {
+		const char *init_args = "-s";
+		size_t init_args_length = strlen(init_args) + 1;
+
+		argv1 = scratch_addr;
+		error = copyout(init_args, argv1, init_args_length);
+		if (error) {
+			return error;
+		}
+
+		scratch_addr = USER_ADDR_ALIGN(scratch_addr + init_args_length, sizeof(user_addr_t));
+	}
+
+	if (proc_is64bit(p)) {
+		user64_addr_t argv64bit[3] = {};
+
+		argv64bit[0] = argv0;
+		argv64bit[1] = argv1;
+		argv64bit[2] = USER_ADDR_NULL;
+
+		error = copyout(argv64bit, scratch_addr, sizeof(argv64bit));
+		if (error) {
+			return error;
+		}
+	} else {
+		user32_addr_t argv32bit[3] = {};
+
+		argv32bit[0] = (user32_addr_t)argv0;
+		argv32bit[1] = (user32_addr_t)argv1;
+		argv32bit[2] = USER_ADDR_NULL;
+
+		error = copyout(argv32bit, scratch_addr, sizeof(argv32bit));
+		if (error) {
+			return error;
+		}
+	}
+
+	/*
+	 * Set up argument block for fake call to execve.
+	 */
+	init_exec_args.fname = argv0;
+	init_exec_args.argp = scratch_addr;
+	init_exec_args.envp = USER_ADDR_NULL;
+
+	/*
+	 * So that init task is set with uid,gid 0 token
+	 */
+	set_security_token(p);
+
+	return execve(p, &init_exec_args, retval);
+}
+
+static const char * init_programs[] = {
+#if DEBUG
+	"/usr/local/sbin/launchd.debug",
+#endif
+#if DEVELOPMENT || DEBUG
+	"/usr/local/sbin/launchd.development",
+#endif
+	"/sbin/launchd",
+};
+
+/*
+ * load_init_program
+ *
+ * Description:	Load the "init" program; in most cases, this will be "launchd"
+ *
+ * Parameters:	p			Process to call execve() to create
+ *					the "init" program
+ *
+ * Returns:	(void)
+ *
+ * Notes:	The process that is passed in is the first manufactured
+ *		process on the system, and gets here via bsd_ast() firing
+ *		for the first time.  This is done to ensure that bsd_init()
+ *		has run to completion.
+ *
+ *		In DEBUG & DEVELOPMENT builds, the launchdsuffix boot-arg
+ *		may be used to select a specific launchd executable. As with
+ *		the kcsuffix boot-arg, setting launchdsuffix to "" or "release"
+ *		will force /sbin/launchd to be selected.
+ *
+ *              Search order by build:
+ *
+ * DEBUG	DEVELOPMENT	RELEASE		PATH
+ * ----------------------------------------------------------------------------------
+ * 1		1		NA		/usr/local/sbin/launchd.$LAUNCHDSUFFIX
+ * 2		NA		NA		/usr/local/sbin/launchd.debug
+ * 3		2		NA		/usr/local/sbin/launchd.development
+ * 4		3		1		/sbin/launchd
+ */
+void
+load_init_program(proc_t p)
+{
+	uint32_t i;
+	int error;
+	vm_map_t map = current_map();
+	mach_vm_offset_t scratch_addr = 0;
+	mach_vm_size_t map_page_size = vm_map_page_size(map);
+
+	(void) mach_vm_allocate_kernel(map, &scratch_addr, map_page_size, VM_FLAGS_ANYWHERE, VM_KERN_MEMORY_NONE);
+#if CONFIG_MEMORYSTATUS
+	(void) memorystatus_init_at_boot_snapshot();
+#endif /* CONFIG_MEMORYSTATUS */
+
+#if DEBUG || DEVELOPMENT
+	/* Check for boot-arg suffix first */
+	char launchd_suffix[64];
+	if (PE_parse_boot_argn("launchdsuffix", launchd_suffix, sizeof(launchd_suffix))) {
+		char launchd_path[128];
+		boolean_t is_release_suffix = ((launchd_suffix[0] == 0) ||
+		    (strcmp(launchd_suffix, "release") == 0));
+
+		if (is_release_suffix) {
+			printf("load_init_program: attempting to load /sbin/launchd\n");
+			error = load_init_program_at_path(p, (user_addr_t)scratch_addr, "/sbin/launchd");
+			if (!error) {
+				return;
+			}
+
+			panic("Process 1 exec of launchd.release failed, errno %d", error);
+		} else {
+			strlcpy(launchd_path, "/usr/local/sbin/launchd.", sizeof(launchd_path));
+			strlcat(launchd_path, launchd_suffix, sizeof(launchd_path));
+
+			printf("load_init_program: attempting to load %s\n", launchd_path);
+			error = load_init_program_at_path(p, (user_addr_t)scratch_addr, launchd_path);
+			if (!error) {
+				return;
+			} else {
+				printf("load_init_program: failed loading %s: errno %d\n", launchd_path, error);
+			}
+		}
+	}
+#endif
+
+	error = ENOENT;
+	for (i = 0; i < sizeof(init_programs) / sizeof(init_programs[0]); i++) {
+		printf("load_init_program: attempting to load %s\n", init_programs[i]);
+		error = load_init_program_at_path(p, (user_addr_t)scratch_addr, init_programs[i]);
+		if (!error) {
+			return;
+		} else {
+			printf("load_init_program: failed loading %s: errno %d\n", init_programs[i], error);
+		}
+	}
+
+	panic("Process 1 exec of %s failed, errno %d", ((i == 0) ? "<null>" : init_programs[i - 1]), error);
+}
+
+/*
+ * load_return_to_errno
+ *
+ * Description:	Convert a load_return_t (Mach error) to an errno (BSD error)
+ *
+ * Parameters:	lrtn			Mach error number
+ *
+ * Returns:	(int)			BSD error number
+ *		0			Success
+ *		EBADARCH		Bad architecture
+ *		EBADMACHO		Bad Mach object file
+ *		ESHLIBVERS		Bad shared library version
+ *		ENOMEM			Out of memory/resource shortage
+ *		EACCES			Access denied
+ *		ENOENT			Entry not found (usually "file does
+ *					does not exist")
+ *		EIO			An I/O error occurred
+ *		EBADEXEC		The executable is corrupt/unknown
+ */
+static int
+load_return_to_errno(load_return_t lrtn)
+{
+	switch (lrtn) {
+	case LOAD_SUCCESS:
+		return 0;
+	case LOAD_BADARCH:
+		return EBADARCH;
+	case LOAD_BADMACHO:
+	case LOAD_BADMACHO_UPX:
+		return EBADMACHO;
+	case LOAD_SHLIB:
+		return ESHLIBVERS;
+	case LOAD_NOSPACE:
+	case LOAD_RESOURCE:
+		return ENOMEM;
+	case LOAD_PROTECT:
+		return EACCES;
+	case LOAD_ENOENT:
+		return ENOENT;
+	case LOAD_IOERROR:
+		return EIO;
+	case LOAD_DECRYPTFAIL:
+		return EAUTH;
+	case LOAD_FAILURE:
+	default:
+		return EBADEXEC;
+	}
+}
+
+#include <mach/mach_types.h>
+#include <mach/vm_prot.h>
+#include <mach/semaphore.h>
+#include <mach/sync_policy.h>
+#include <kern/clock.h>
+#include <mach/kern_return.h>
+
+/*
+ * execargs_alloc
+ *
+ * Description:	Allocate the block of memory used by the execve arguments.
+ *		At the same time, we allocate a page so that we can read in
+ *		the first page of the image.
+ *
+ * Parameters:	struct image_params *	the image parameter block
+ *
+ * Returns:	0			Success
+ *		EINVAL			Invalid argument
+ *		EACCES			Permission denied
+ *		EINTR			Interrupted function
+ *		ENOMEM			Not enough space
+ *
+ * Notes:	This is a temporary allocation into the kernel address space
+ *		to enable us to copy arguments in from user space.  This is
+ *		necessitated by not mapping the process calling execve() into
+ *		the kernel address space during the execve() system call.
+ *
+ *		We assemble the argument and environment, etc., into this
+ *		region before copying it as a single block into the child
+ *		process address space (at the top or bottom of the stack,
+ *		depending on which way the stack grows; see the function
+ *		exec_copyout_strings() for details).
+ *
+ *		This ends up with a second (possibly unnecessary) copy compared
+ *		with assembing the data directly into the child address space,
+ *		instead, but since we cannot be guaranteed that the parent has
+ *		not modified its environment, we can't really know that it's
+ *		really a block there as well.
+ */
+
+
+static int execargs_waiters = 0;
+lck_mtx_t *execargs_cache_lock;
+
+static void
+execargs_lock_lock(void)
+{
+	lck_mtx_lock_spin(execargs_cache_lock);
+}
+
+static void
+execargs_lock_unlock(void)
+{
+	lck_mtx_unlock(execargs_cache_lock);
+}
+
+static wait_result_t
+execargs_lock_sleep(void)
+{
+	return lck_mtx_sleep(execargs_cache_lock, LCK_SLEEP_DEFAULT, &execargs_free_count, THREAD_INTERRUPTIBLE);
+}
+
+static kern_return_t
+execargs_purgeable_allocate(char **execarg_address)
+{
+	kern_return_t kr = vm_allocate_kernel(bsd_pageable_map, (vm_offset_t *)execarg_address, BSD_PAGEABLE_SIZE_PER_EXEC, VM_FLAGS_ANYWHERE | VM_FLAGS_PURGABLE, VM_KERN_MEMORY_NONE);
+	assert(kr == KERN_SUCCESS);
+	return kr;
+}
+
+static kern_return_t
+execargs_purgeable_reference(void *execarg_address)
+{
+	int state = VM_PURGABLE_NONVOLATILE;
+	kern_return_t kr = vm_purgable_control(bsd_pageable_map, (vm_offset_t) execarg_address, VM_PURGABLE_SET_STATE, &state);
+
+	assert(kr == KERN_SUCCESS);
+	return kr;
+}
+
+static kern_return_t
+execargs_purgeable_volatilize(void *execarg_address)
+{
+	int state = VM_PURGABLE_VOLATILE | VM_PURGABLE_ORDERING_OBSOLETE;
+	kern_return_t kr;
+	kr = vm_purgable_control(bsd_pageable_map, (vm_offset_t) execarg_address, VM_PURGABLE_SET_STATE, &state);
+
+	assert(kr == KERN_SUCCESS);
+
+	return kr;
+}
+
+static void
+execargs_wakeup_waiters(void)
+{
+	thread_wakeup(&execargs_free_count);
+}
+
+static int
+execargs_alloc(struct image_params *imgp)
+{
+	kern_return_t kret;
+	wait_result_t res;
+	int i, cache_index = -1;
+
+	execargs_lock_lock();
+
+	while (execargs_free_count == 0) {
+		execargs_waiters++;
+		res = execargs_lock_sleep();
+		execargs_waiters--;
+		if (res != THREAD_AWAKENED) {
+			execargs_lock_unlock();
+			return EINTR;
+		}
+	}
+
+	execargs_free_count--;
+
+	for (i = 0; i < execargs_cache_size; i++) {
+		vm_offset_t element = execargs_cache[i];
+		if (element) {
+			cache_index = i;
+			imgp->ip_strings = (char *)(execargs_cache[i]);
+			execargs_cache[i] = 0;
+			break;
+		}
+	}
+
+	assert(execargs_free_count >= 0);
+
+	execargs_lock_unlock();
+
+	if (cache_index == -1) {
+		kret = execargs_purgeable_allocate(&imgp->ip_strings);
+	} else {
+		kret = execargs_purgeable_reference(imgp->ip_strings);
+	}
+
+	assert(kret == KERN_SUCCESS);
+	if (kret != KERN_SUCCESS) {
+		return ENOMEM;
+	}
+
+	/* last page used to read in file headers */
+	imgp->ip_vdata = imgp->ip_strings + (NCARGS + PAGE_SIZE);
+	imgp->ip_strendp = imgp->ip_strings;
+	imgp->ip_argspace = NCARGS;
+	imgp->ip_strspace = (NCARGS + PAGE_SIZE);
+
+	return 0;
+}
+
+/*
+ * execargs_free
+ *
+ * Description:	Free the block of memory used by the execve arguments and the
+ *		first page of the executable by a previous call to the function
+ *		execargs_alloc().
+ *
+ * Parameters:	struct image_params *	the image parameter block
+ *
+ * Returns:	0			Success
+ *		EINVAL			Invalid argument
+ *		EINTR			Oeration interrupted
+ */
+static int
+execargs_free(struct image_params *imgp)
+{
+	kern_return_t kret;
+	int i;
+	boolean_t needs_wakeup = FALSE;
+
+	kret = execargs_purgeable_volatilize(imgp->ip_strings);
+
+	execargs_lock_lock();
+	execargs_free_count++;
+
+	for (i = 0; i < execargs_cache_size; i++) {
+		vm_offset_t element = execargs_cache[i];
+		if (element == 0) {
+			execargs_cache[i] = (vm_offset_t) imgp->ip_strings;
+			imgp->ip_strings = NULL;
+			break;
+		}
+	}
+
+	assert(imgp->ip_strings == NULL);
+
+	if (execargs_waiters > 0) {
+		needs_wakeup = TRUE;
+	}
+
+	execargs_lock_unlock();
+
+	if (needs_wakeup == TRUE) {
+		execargs_wakeup_waiters();
+	}
+
+	return kret == KERN_SUCCESS ? 0 : EINVAL;
+}
+
+static void
+exec_resettextvp(proc_t p, struct image_params *imgp)
+{
+	vnode_t vp;
+	off_t offset;
+	vnode_t tvp  = p->p_textvp;
+	int ret;
+
+	vp = imgp->ip_vp;
+	offset = imgp->ip_arch_offset;
+
+	if (vp == NULLVP) {
+		panic("exec_resettextvp: expected valid vp");
+	}
+
+	ret = vnode_ref(vp);
+	proc_lock(p);
+	if (ret == 0) {
+		p->p_textvp = vp;
+		p->p_textoff = offset;
+	} else {
+		p->p_textvp = NULLVP;   /* this is paranoia */
+		p->p_textoff = 0;
+	}
+	proc_unlock(p);
+
+	if (tvp != NULLVP) {
+		if (vnode_getwithref(tvp) == 0) {
+			vnode_rele(tvp);
+			vnode_put(tvp);
+		}
+	}
+}
+
+// Includes the 0-byte (therefore "SIZE" instead of "LEN").
+static const size_t CS_CDHASH_STRING_SIZE = CS_CDHASH_LEN * 2 + 1;
+
+static void
+cdhash_to_string(char str[CS_CDHASH_STRING_SIZE], uint8_t const * const cdhash)
+{
+	static char const nibble[] = "0123456789abcdef";
+
+	/* Apparently still the safest way to get a hex representation
+	 * of binary data.
+	 * xnu's printf routines have %*D/%20D in theory, but "not really", see:
+	 * <rdar://problem/33328859> confusion around %*D/%nD in printf
+	 */
+	for (int i = 0; i < CS_CDHASH_LEN; ++i) {
+		str[i * 2] = nibble[(cdhash[i] & 0xf0) >> 4];
+		str[i * 2 + 1] = nibble[cdhash[i] & 0x0f];
+	}
+	str[CS_CDHASH_STRING_SIZE - 1] = 0;
+}
+
+/*
+ * __EXEC_WAITING_ON_TASKGATED_CODE_SIGNATURE_UPCALL__
+ *
+ * Description: Waits for the userspace daemon to respond to the request
+ *              we made. Function declared non inline to be visible in
+ *		stackshots and spindumps as well as debugging.
+ */
+__attribute__((noinline)) int
+__EXEC_WAITING_ON_TASKGATED_CODE_SIGNATURE_UPCALL__(mach_port_t task_access_port, int32_t new_pid)
+{
+	return find_code_signature(task_access_port, new_pid);
+}
+
+static int
+check_for_signature(proc_t p, struct image_params *imgp)
+{
+	mach_port_t port = IPC_PORT_NULL;
+	kern_return_t kr = KERN_FAILURE;
+	int error = EACCES;
+	boolean_t unexpected_failure = FALSE;
+	struct cs_blob *csb;
+	boolean_t require_success = FALSE;
+	int spawn = (imgp->ip_flags & IMGPF_SPAWN);
+	int vfexec = (imgp->ip_flags & IMGPF_VFORK_EXEC);
+	os_reason_t signature_failure_reason = OS_REASON_NULL;
+
+	/*
+	 * Override inherited code signing flags with the
+	 * ones for the process that is being successfully
+	 * loaded
+	 */
+	proc_lock(p);
+	p->p_csflags = imgp->ip_csflags;
+	proc_unlock(p);
+
+	/* Set the switch_protect flag on the map */
+	if (p->p_csflags & (CS_HARD | CS_KILL)) {
+		vm_map_switch_protect(get_task_map(p->task), TRUE);
+	}
+
+	/*
+	 * image activation may be failed due to policy
+	 * which is unexpected but security framework does not
+	 * approve of exec, kill and return immediately.
+	 */
+	if (imgp->ip_mac_return != 0) {
+		KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
+		    p->p_pid, OS_REASON_EXEC, EXEC_EXIT_REASON_SECURITY_POLICY, 0, 0);
+		signature_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_SECURITY_POLICY);
+		error = imgp->ip_mac_return;
+		unexpected_failure = TRUE;
+		goto done;
+	}
+
+	if (imgp->ip_cs_error != OS_REASON_NULL) {
+		signature_failure_reason = imgp->ip_cs_error;
+		imgp->ip_cs_error = OS_REASON_NULL;
+		error = EACCES;
+		goto done;
+	}
+
+	/* If the code signature came through the image activation path, we skip the
+	 * taskgated / externally attached path. */
+	if (imgp->ip_csflags & CS_SIGNED) {
+		error = 0;
+		goto done;
+	}
+
+	/* The rest of the code is for signatures that either already have been externally
+	 * attached (likely, but not necessarily by a previous run through the taskgated
+	 * path), or that will now be attached by taskgated. */
+
+	kr = task_get_task_access_port(p->task, &port);
+	if (KERN_SUCCESS != kr || !IPC_PORT_VALID(port)) {
+		error = 0;
+		if (require_success) {
+			KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
+			    p->p_pid, OS_REASON_CODESIGNING, CODESIGNING_EXIT_REASON_TASK_ACCESS_PORT, 0, 0);
+			signature_failure_reason = os_reason_create(OS_REASON_CODESIGNING, CODESIGNING_EXIT_REASON_TASK_ACCESS_PORT);
+			error = EACCES;
+		}
+		goto done;
+	}
+
+	/*
+	 * taskgated returns KERN_SUCCESS if it has completed its work
+	 * and the exec should continue, KERN_FAILURE if the exec should
+	 * fail, or it may error out with different error code in an
+	 * event of mig failure (e.g. process was signalled during the
+	 * rpc call, taskgated died, mig server died etc.).
+	 */
+
+	kr = __EXEC_WAITING_ON_TASKGATED_CODE_SIGNATURE_UPCALL__(port, p->p_pid);
+	switch (kr) {
+	case KERN_SUCCESS:
+		error = 0;
+		break;
+	case KERN_FAILURE:
+		error = EACCES;
+
+		KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
+		    p->p_pid, OS_REASON_CODESIGNING, CODESIGNING_EXIT_REASON_TASKGATED_INVALID_SIG, 0, 0);
+		signature_failure_reason = os_reason_create(OS_REASON_CODESIGNING, CODESIGNING_EXIT_REASON_TASKGATED_INVALID_SIG);
+		goto done;
+	default:
+		error = EACCES;
+
+		KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
+		    p->p_pid, OS_REASON_EXEC, EXEC_EXIT_REASON_TASKGATED_OTHER, 0, 0);
+		signature_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_TASKGATED_OTHER);
+		unexpected_failure = TRUE;
+		goto done;
+	}
+
+	/* Only do this if exec_resettextvp() did not fail */
+	if (p->p_textvp != NULLVP) {
+		csb = ubc_cs_blob_get(p->p_textvp, -1, p->p_textoff);
+
+		if (csb != NULL) {
+			/* As the enforcement we can do here is very limited, we only allow things that
+			 * are the only reason why this code path still exists:
+			 * Adhoc signed non-platform binaries without special cs_flags and without any
+			 * entitlements (unrestricted ones still pass AMFI). */
+			if (
+				/* Revalidate the blob if necessary through bumped generation count. */
+				(ubc_cs_generation_check(p->p_textvp) == 0 ||
+				ubc_cs_blob_revalidate(p->p_textvp, csb, imgp, 0) == 0) &&
+				/* Only CS_ADHOC, no CS_KILL, CS_HARD etc. */
+				(csb->csb_flags & CS_ALLOWED_MACHO) == CS_ADHOC &&
+				/* If it has a CMS blob, it's not adhoc. The CS_ADHOC flag can lie. */
+				csblob_find_blob_bytes((const uint8_t *)csb->csb_mem_kaddr, csb->csb_mem_size,
+				CSSLOT_SIGNATURESLOT,
+				CSMAGIC_BLOBWRAPPER) == NULL &&
+				/* It could still be in a trust cache (unlikely with CS_ADHOC), or a magic path. */
+				csb->csb_platform_binary == 0 &&
+				/* No entitlements, not even unrestricted ones. */
+				csb->csb_entitlements_blob == NULL) {
+				proc_lock(p);
+				p->p_csflags |= CS_SIGNED | CS_VALID;
+				proc_unlock(p);
+			} else {
+				uint8_t cdhash[CS_CDHASH_LEN];
+				char cdhash_string[CS_CDHASH_STRING_SIZE];
+				proc_getcdhash(p, cdhash);
+				cdhash_to_string(cdhash_string, cdhash);
+				printf("ignoring detached code signature on '%s' with cdhash '%s' "
+				    "because it is invalid, or not a simple adhoc signature.\n",
+				    p->p_name, cdhash_string);
+			}
+		}
+	}
+
+done:
+	if (0 == error) {
+		/* The process's code signature related properties are
+		 * fully set up, so this is an opportune moment to log
+		 * platform binary execution, if desired. */
+		if (platform_exec_logging != 0 && csproc_get_platform_binary(p)) {
+			uint8_t cdhash[CS_CDHASH_LEN];
+			char cdhash_string[CS_CDHASH_STRING_SIZE];
+			proc_getcdhash(p, cdhash);
+			cdhash_to_string(cdhash_string, cdhash);
+
+			os_log(peLog, "CS Platform Exec Logging: Executing platform signed binary "
+			    "'%s' with cdhash %s\n", p->p_name, cdhash_string);
+		}
+	} else {
+		if (!unexpected_failure) {
+			p->p_csflags |= CS_KILLED;
+		}
+		/* make very sure execution fails */
+		if (vfexec || spawn) {
+			assert(signature_failure_reason != OS_REASON_NULL);
+			psignal_vfork_with_reason(p, p->task, imgp->ip_new_thread,
+			    SIGKILL, signature_failure_reason);
+			signature_failure_reason = OS_REASON_NULL;
+			error = 0;
+		} else {
+			assert(signature_failure_reason != OS_REASON_NULL);
+			psignal_with_reason(p, SIGKILL, signature_failure_reason);
+			signature_failure_reason = OS_REASON_NULL;
+		}
+	}
+
+	if (port != IPC_PORT_NULL) {
+		ipc_port_release_send(port);
+	}
+
+	/* If we hit this, we likely would have leaked an exit reason */
+	assert(signature_failure_reason == OS_REASON_NULL);
+	return error;
+}
+
+/*
+ * Typically as soon as we start executing this process, the
+ * first instruction will trigger a VM fault to bring the text
+ * pages (as executable) into the address space, followed soon
+ * thereafter by dyld data structures (for dynamic executable).
+ * To optimize this, as well as improve support for hardware
+ * debuggers that can only access resident pages present
+ * in the process' page tables, we prefault some pages if
+ * possible. Errors are non-fatal.
+ */
+static void
+exec_prefault_data(proc_t p __unused, struct image_params *imgp, load_result_t *load_result)
+{
+	int ret;
+	size_t expected_all_image_infos_size;
+
+	/*
+	 * Prefault executable or dyld entry point.
+	 */
+	vm_fault(current_map(),
+	    vm_map_trunc_page(load_result->entry_point,
+	    vm_map_page_mask(current_map())),
+	    VM_PROT_READ | VM_PROT_EXECUTE,
+	    FALSE, VM_KERN_MEMORY_NONE,
+	    THREAD_UNINT, NULL, 0);
+
+	if (imgp->ip_flags & IMGPF_IS_64BIT_ADDR) {
+		expected_all_image_infos_size = sizeof(struct user64_dyld_all_image_infos);
+	} else {
+		expected_all_image_infos_size = sizeof(struct user32_dyld_all_image_infos);
+	}
+
+	/* Decode dyld anchor structure from <mach-o/dyld_images.h> */
+	if (load_result->dynlinker &&
+	    load_result->all_image_info_addr &&
+	    load_result->all_image_info_size >= expected_all_image_infos_size) {
+		union {
+			struct user64_dyld_all_image_infos      infos64;
+			struct user32_dyld_all_image_infos      infos32;
+		} all_image_infos;
+
+		/*
+		 * Pre-fault to avoid copyin() going through the trap handler
+		 * and recovery path.
+		 */
+		vm_fault(current_map(),
+		    vm_map_trunc_page(load_result->all_image_info_addr,
+		    vm_map_page_mask(current_map())),
+		    VM_PROT_READ | VM_PROT_WRITE,
+		    FALSE, VM_KERN_MEMORY_NONE,
+		    THREAD_UNINT, NULL, 0);
+		if ((load_result->all_image_info_addr & PAGE_MASK) + expected_all_image_infos_size > PAGE_SIZE) {
+			/* all_image_infos straddles a page */
+			vm_fault(current_map(),
+			    vm_map_trunc_page(load_result->all_image_info_addr + expected_all_image_infos_size - 1,
+			    vm_map_page_mask(current_map())),
+			    VM_PROT_READ | VM_PROT_WRITE,
+			    FALSE, VM_KERN_MEMORY_NONE,
+			    THREAD_UNINT, NULL, 0);
+		}
+
+		ret = copyin(load_result->all_image_info_addr,
+		    &all_image_infos,
+		    expected_all_image_infos_size);
+		if (ret == 0 && all_image_infos.infos32.version >= DYLD_ALL_IMAGE_INFOS_ADDRESS_MINIMUM_VERSION) {
+			user_addr_t notification_address;
+			user_addr_t dyld_image_address;
+			user_addr_t dyld_version_address;
+			user_addr_t dyld_all_image_infos_address;
+			user_addr_t dyld_slide_amount;
+
+			if (imgp->ip_flags & IMGPF_IS_64BIT_ADDR) {
+				notification_address = all_image_infos.infos64.notification;
+				dyld_image_address = all_image_infos.infos64.dyldImageLoadAddress;
+				dyld_version_address = all_image_infos.infos64.dyldVersion;
+				dyld_all_image_infos_address = all_image_infos.infos64.dyldAllImageInfosAddress;
+			} else {
+				notification_address = all_image_infos.infos32.notification;
+				dyld_image_address = all_image_infos.infos32.dyldImageLoadAddress;
+				dyld_version_address = all_image_infos.infos32.dyldVersion;
+				dyld_all_image_infos_address = all_image_infos.infos32.dyldAllImageInfosAddress;
+			}
+
+			/*
+			 * dyld statically sets up the all_image_infos in its Mach-O
+			 * binary at static link time, with pointers relative to its default
+			 * load address. Since ASLR might slide dyld before its first
+			 * instruction is executed, "dyld_slide_amount" tells us how far
+			 * dyld was loaded compared to its default expected load address.
+			 * All other pointers into dyld's image should be adjusted by this
+			 * amount. At some point later, dyld will fix up pointers to take
+			 * into account the slide, at which point the all_image_infos_address
+			 * field in the structure will match the runtime load address, and
+			 * "dyld_slide_amount" will be 0, if we were to consult it again.
+			 */
+
+			dyld_slide_amount = load_result->all_image_info_addr - dyld_all_image_infos_address;
+
+#if 0
+			kprintf("exec_prefault: 0x%016llx 0x%08x 0x%016llx 0x%016llx 0x%016llx 0x%016llx\n",
+			    (uint64_t)load_result->all_image_info_addr,
+			    all_image_infos.infos32.version,
+			    (uint64_t)notification_address,
+			    (uint64_t)dyld_image_address,
+			    (uint64_t)dyld_version_address,
+			    (uint64_t)dyld_all_image_infos_address);
+#endif
+
+			vm_fault(current_map(),
+			    vm_map_trunc_page(notification_address + dyld_slide_amount,
+			    vm_map_page_mask(current_map())),
+			    VM_PROT_READ | VM_PROT_EXECUTE,
+			    FALSE, VM_KERN_MEMORY_NONE,
+			    THREAD_UNINT, NULL, 0);
+			vm_fault(current_map(),
+			    vm_map_trunc_page(dyld_image_address + dyld_slide_amount,
+			    vm_map_page_mask(current_map())),
+			    VM_PROT_READ | VM_PROT_EXECUTE,
+			    FALSE, VM_KERN_MEMORY_NONE,
+			    THREAD_UNINT, NULL, 0);
+			vm_fault(current_map(),
+			    vm_map_trunc_page(dyld_version_address + dyld_slide_amount,
+			    vm_map_page_mask(current_map())),
+			    VM_PROT_READ,
+			    FALSE, VM_KERN_MEMORY_NONE,
+			    THREAD_UNINT, NULL, 0);
+			vm_fault(current_map(),
+			    vm_map_trunc_page(dyld_all_image_infos_address + dyld_slide_amount,
+			    vm_map_page_mask(current_map())),
+			    VM_PROT_READ | VM_PROT_WRITE,
+			    FALSE, VM_KERN_MEMORY_NONE,
+			    THREAD_UNINT, NULL, 0);
+		}
 	}
 }