xnu-6153.11.26.tar.gz

[apple/xnu.git] / bsd / kern / kern_mman.c

/*
 * Copyright (c) 2007-2019 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, 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) 1988 University of Utah.
 * Copyright (c) 1991, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * the Systems Programming Group of the University of Utah Computer
 * Science Department.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * from: Utah $Hdr: vm_mmap.c 1.6 91/10/21$
 *
 *      @(#)vm_mmap.c   8.10 (Berkeley) 2/19/95
 */
/*
 * 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.
 */

/*
 * Mapped file (mmap) interface to VM
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/filedesc.h>
#include <sys/proc_internal.h>
#include <sys/kauth.h>
#include <sys/resourcevar.h>
#include <sys/vnode_internal.h>
#include <sys/acct.h>
#include <sys/wait.h>
#include <sys/file_internal.h>
#include <sys/vadvise.h>
#include <sys/trace.h>
#include <sys/mman.h>
#include <sys/conf.h>
#include <sys/stat.h>
#include <sys/ubc.h>
#include <sys/ubc_internal.h>
#include <sys/sysproto.h>

#include <sys/syscall.h>
#include <sys/kdebug.h>
#include <sys/bsdtask_info.h>

#include <security/audit/audit.h>
#include <bsm/audit_kevents.h>

#include <mach/mach_types.h>
#include <mach/mach_traps.h>
#include <mach/vm_sync.h>
#include <mach/vm_behavior.h>
#include <mach/vm_inherit.h>
#include <mach/vm_statistics.h>
#include <mach/mach_vm.h>
#include <mach/vm_map.h>
#include <mach/host_priv.h>
#include <mach/sdt.h>

#include <machine/machine_routines.h>

#include <kern/cpu_number.h>
#include <kern/host.h>
#include <kern/task.h>
#include <kern/page_decrypt.h>

#include <IOKit/IOReturn.h>

#include <vm/vm_map.h>
#include <vm/vm_kern.h>
#include <vm/vm_pager.h>
#include <vm/vm_protos.h>

#if CONFIG_MACF
#include <security/mac_framework.h>
#endif
#include <os/overflow.h>

#ifndef CONFIG_EMBEDDED
#include <IOKit/IOBSD.h> /* for IOTaskHasEntitlement */
#include <sys/csr.h> /* for csr_check */
#define MAP_32BIT_ENTITLEMENT "com.apple.security.mmap-map-32bit"
#endif

/*
 * XXX Internally, we use VM_PROT_* somewhat interchangeably, but the correct
 * XXX usage is PROT_* from an interface perspective.  Thus the values of
 * XXX VM_PROT_* and PROT_* need to correspond.
 */
int
mmap(proc_t p, struct mmap_args *uap, user_addr_t *retval)
{
        /*
         *      Map in special device (must be SHARED) or file
         */
        struct fileproc *fp;
        struct                  vnode *vp;
        int                     flags;
        int                     prot;
        int                     err = 0;
        vm_map_t                user_map;
        kern_return_t           result;
        vm_map_offset_t         user_addr;
        vm_map_offset_t         sum;
        vm_map_size_t           user_size;
        vm_object_offset_t      pageoff;
        vm_object_offset_t      file_pos;
        int                     alloc_flags = 0;
        vm_tag_t                tag = VM_KERN_MEMORY_NONE;
        vm_map_kernel_flags_t   vmk_flags = VM_MAP_KERNEL_FLAGS_NONE;
        boolean_t               docow;
        vm_prot_t               maxprot;
        void                    *handle;
        memory_object_t         pager = MEMORY_OBJECT_NULL;
        memory_object_control_t  control;
        int                     mapanon = 0;
        int                     fpref = 0;
        int error = 0;
        int fd = uap->fd;
        int num_retries = 0;

        /*
         * Note that for UNIX03 conformance, there is additional parameter checking for
         * mmap() system call in libsyscall prior to entering the kernel.  The sanity
         * checks and argument validation done in this function are not the only places
         * one can get returned errnos.
         */

        user_map = current_map();
        user_addr = (vm_map_offset_t)uap->addr;
        user_size = (vm_map_size_t) uap->len;

        AUDIT_ARG(addr, user_addr);
        AUDIT_ARG(len, user_size);
        AUDIT_ARG(fd, uap->fd);

        if (vm_map_range_overflows(user_addr, user_size)) {
                return EINVAL;
        }
        prot = (uap->prot & VM_PROT_ALL);
#if 3777787
        /*
         * Since the hardware currently does not support writing without
         * read-before-write, or execution-without-read, if the request is
         * for write or execute access, we must imply read access as well;
         * otherwise programs expecting this to work will fail to operate.
         */
        if (prot & (VM_PROT_EXECUTE | VM_PROT_WRITE)) {
                prot |= VM_PROT_READ;
        }
#endif  /* radar 3777787 */

        flags = uap->flags;
        vp = NULLVP;

        /*
         * The vm code does not have prototypes & compiler doesn't do
         * the right thing when you cast 64bit value and pass it in function
         * call. So here it is.
         */
        file_pos = (vm_object_offset_t)uap->pos;


        /* make sure mapping fits into numeric range etc */
        if (os_add3_overflow(file_pos, user_size, PAGE_SIZE_64 - 1, &sum)) {
                return EINVAL;
        }

        /*
         * Align the file position to a page boundary,
         * and save its page offset component.
         */
        pageoff = (file_pos & vm_map_page_mask(user_map));
        file_pos -= (vm_object_offset_t)pageoff;


        /* Adjust size for rounding (on both ends). */
        user_size += pageoff;   /* low end... */
        user_size = vm_map_round_page(user_size,
            vm_map_page_mask(user_map));                           /* hi end */

        if (flags & MAP_JIT) {
                if ((flags & MAP_FIXED) ||
                    (flags & MAP_SHARED) ||
                    !(flags & MAP_ANON) ||
                    (flags & MAP_RESILIENT_CODESIGN) ||
                    (flags & MAP_RESILIENT_MEDIA)) {
                        return EINVAL;
                }
        }

        if ((flags & MAP_RESILIENT_CODESIGN) ||
            (flags & MAP_RESILIENT_MEDIA)) {
                if ((flags & MAP_ANON) ||
                    (flags & MAP_JIT)) {
                        return EINVAL;
                }
        }
        if (flags & MAP_RESILIENT_CODESIGN) {
                if (prot & (VM_PROT_WRITE | VM_PROT_EXECUTE)) {
                        return EPERM;
                }
        }
        if (flags & MAP_SHARED) {
                /*
                 * MAP_RESILIENT_MEDIA is not valid with MAP_SHARED because
                 * there is no place to inject zero-filled pages without
                 * actually adding them to the file.
                 * Since we didn't reject that combination before, there might
                 * already be callers using it and getting a valid MAP_SHARED
                 * mapping but without the resilience.
                 * For backwards compatibility's sake, let's keep ignoring
                 * MAP_RESILIENT_MEDIA in that case.
                 */
                flags &= ~MAP_RESILIENT_MEDIA;
        }
        if (flags & MAP_RESILIENT_MEDIA) {
                if ((flags & MAP_ANON) ||
                    (flags & MAP_SHARED)) {
                        return EINVAL;
                }
        }

        /*
         * Check for illegal addresses.  Watch out for address wrap... Note
         * that VM_*_ADDRESS are not constants due to casts (argh).
         */
        if (flags & MAP_FIXED) {
                /*
                 * The specified address must have the same remainder
                 * as the file offset taken modulo PAGE_SIZE, so it
                 * should be aligned after adjustment by pageoff.
                 */
                user_addr -= pageoff;
                if (user_addr & vm_map_page_mask(user_map)) {
                        return EINVAL;
                }
        }
#ifdef notyet
        /* DO not have apis to get this info, need to wait till then*/
        /*
         * XXX for non-fixed mappings where no hint is provided or
         * the hint would fall in the potential heap space,
         * place it after the end of the largest possible heap.
         *
         * There should really be a pmap call to determine a reasonable
         * location.
         */
        else if (addr < vm_map_round_page(p->p_vmspace->vm_daddr + MAXDSIZ,
            vm_map_page_mask(user_map))) {
                addr = vm_map_round_page(p->p_vmspace->vm_daddr + MAXDSIZ,
                    vm_map_page_mask(user_map));
        }

#endif

        alloc_flags = 0;

        if (flags & MAP_ANON) {
                maxprot = VM_PROT_ALL;
#if CONFIG_MACF
                /*
                 * Entitlement check.
                 */
                error = mac_proc_check_map_anon(p, user_addr, user_size, prot, flags, &maxprot);
                if (error) {
                        return EINVAL;
                }
#endif /* MAC */

                /*
                 * Mapping blank space is trivial.  Use positive fds as the alias
                 * value for memory tracking.
                 */
                if (fd != -1) {
                        /*
                         * Use "fd" to pass (some) Mach VM allocation flags,
                         * (see the VM_FLAGS_* definitions).
                         */
                        alloc_flags = fd & (VM_FLAGS_ALIAS_MASK |
                            VM_FLAGS_SUPERPAGE_MASK |
                            VM_FLAGS_PURGABLE |
                            VM_FLAGS_4GB_CHUNK);
                        if (alloc_flags != fd) {
                                /* reject if there are any extra flags */
                                return EINVAL;
                        }
                        VM_GET_FLAGS_ALIAS(alloc_flags, tag);
                        alloc_flags &= ~VM_FLAGS_ALIAS_MASK;
                }

                handle = NULL;
                file_pos = 0;
                mapanon = 1;
        } else {
                struct vnode_attr va;
                vfs_context_t ctx = vfs_context_current();

                if (flags & MAP_JIT) {
                        return EINVAL;
                }

                /*
                 * Mapping file, get fp for validation. Obtain vnode and make
                 * sure it is of appropriate type.
                 */
                err = fp_lookup(p, fd, &fp, 0);
                if (err) {
                        return err;
                }
                fpref = 1;
                switch (FILEGLOB_DTYPE(fp->f_fglob)) {
                case DTYPE_PSXSHM:
                        uap->addr = (user_addr_t)user_addr;
                        uap->len = (user_size_t)user_size;
                        uap->prot = prot;
                        uap->flags = flags;
                        uap->pos = file_pos;
                        error = pshm_mmap(p, uap, retval, fp, (off_t)pageoff);
                        goto bad;
                case DTYPE_VNODE:
                        break;
                default:
                        error = EINVAL;
                        goto bad;
                }
                vp = (struct vnode *)fp->f_fglob->fg_data;
                error = vnode_getwithref(vp);
                if (error != 0) {
                        goto bad;
                }

                if (vp->v_type != VREG && vp->v_type != VCHR) {
                        (void)vnode_put(vp);
                        error = EINVAL;
                        goto bad;
                }

                AUDIT_ARG(vnpath, vp, ARG_VNODE1);

                /*
                 * POSIX: mmap needs to update access time for mapped files
                 */
                if ((vnode_vfsvisflags(vp) & MNT_NOATIME) == 0) {
                        VATTR_INIT(&va);
                        nanotime(&va.va_access_time);
                        VATTR_SET_ACTIVE(&va, va_access_time);
                        vnode_setattr(vp, &va, ctx);
                }

                /*
                 * XXX hack to handle use of /dev/zero to map anon memory (ala
                 * SunOS).
                 */
                if (vp->v_type == VCHR || vp->v_type == VSTR) {
                        (void)vnode_put(vp);
                        error = ENODEV;
                        goto bad;
                } else {
                        /*
                         * Ensure that file and memory protections are
                         * compatible.  Note that we only worry about
                         * writability if mapping is shared; in this case,
                         * current and max prot are dictated by the open file.
                         * XXX use the vnode instead?  Problem is: what
                         * credentials do we use for determination? What if
                         * proc does a setuid?
                         */
                        maxprot = VM_PROT_EXECUTE;      /* ??? */
                        if (fp->f_fglob->fg_flag & FREAD) {
                                maxprot |= VM_PROT_READ;
                        } else if (prot & PROT_READ) {
                                (void)vnode_put(vp);
                                error = EACCES;
                                goto bad;
                        }
                        /*
                         * If we are sharing potential changes (either via
                         * MAP_SHARED or via the implicit sharing of character
                         * device mappings), and we are trying to get write
                         * permission although we opened it without asking
                         * for it, bail out.
                         */

                        if ((flags & MAP_SHARED) != 0) {
                                if ((fp->f_fglob->fg_flag & FWRITE) != 0 &&
                                    /*
                                     * Do not allow writable mappings of
                                     * swap files (see vm_swapfile_pager.c).
                                     */
                                    !vnode_isswap(vp)) {
                                        /*
                                         * check for write access
                                         *
                                         * Note that we already made this check when granting FWRITE
                                         * against the file, so it seems redundant here.
                                         */
                                        error = vnode_authorize(vp, NULL, KAUTH_VNODE_CHECKIMMUTABLE, ctx);

                                        /* if not granted for any reason, but we wanted it, bad */
                                        if ((prot & PROT_WRITE) && (error != 0)) {
                                                vnode_put(vp);
                                                goto bad;
                                        }

                                        /* if writable, remember */
                                        if (error == 0) {
                                                maxprot |= VM_PROT_WRITE;
                                        }
                                } else if ((prot & PROT_WRITE) != 0) {
                                        (void)vnode_put(vp);
                                        error = EACCES;
                                        goto bad;
                                }
                        } else {
                                maxprot |= VM_PROT_WRITE;
                        }

                        handle = (void *)vp;
#if CONFIG_MACF
                        error = mac_file_check_mmap(vfs_context_ucred(ctx),
                            fp->f_fglob, prot, flags, file_pos, &maxprot);
                        if (error) {
                                (void)vnode_put(vp);
                                goto bad;
                        }
#endif /* MAC */
                        /*
                         * Consult the file system to determine if this
                         * particular file object can be mapped.
                         */
                        error = VNOP_MMAP_CHECK(vp, prot, ctx);
                        if (error) {
                                (void)vnode_put(vp);
                                goto bad;
                        }
                }

                /*
                 * No copy-on-read for mmap() mappings themselves.
                 */
                vmk_flags.vmkf_no_copy_on_read = 1;
        }

        if (user_size == 0) {
                if (!mapanon) {
                        (void)vnode_put(vp);
                }
                error = 0;
                goto bad;
        }

        /*
         *      We bend a little - round the start and end addresses
         *      to the nearest page boundary.
         */
        user_size = vm_map_round_page(user_size,
            vm_map_page_mask(user_map));

        if (file_pos & vm_map_page_mask(user_map)) {
                if (!mapanon) {
                        (void)vnode_put(vp);
                }
                error = EINVAL;
                goto bad;
        }

        if ((flags & MAP_FIXED) == 0) {
                alloc_flags |= VM_FLAGS_ANYWHERE;
                user_addr = vm_map_round_page(user_addr,
                    vm_map_page_mask(user_map));
        } else {
                if (user_addr != vm_map_trunc_page(user_addr,
                    vm_map_page_mask(user_map))) {
                        if (!mapanon) {
                                (void)vnode_put(vp);
                        }
                        error = EINVAL;
                        goto bad;
                }
                /*
                 * mmap(MAP_FIXED) will replace any existing mappings in the
                 * specified range, if the new mapping is successful.
                 * If we just deallocate the specified address range here,
                 * another thread might jump in and allocate memory in that
                 * range before we get a chance to establish the new mapping,
                 * and we won't have a chance to restore the old mappings.
                 * So we use VM_FLAGS_OVERWRITE to let Mach VM know that it
                 * has to deallocate the existing mappings and establish the
                 * new ones atomically.
                 */
                alloc_flags |= VM_FLAGS_FIXED | VM_FLAGS_OVERWRITE;
        }

        if (flags & MAP_NOCACHE) {
                alloc_flags |= VM_FLAGS_NO_CACHE;
        }

        if (flags & MAP_JIT) {
                vmk_flags.vmkf_map_jit = TRUE;
        }

        if (flags & MAP_RESILIENT_CODESIGN) {
                alloc_flags |= VM_FLAGS_RESILIENT_CODESIGN;
        }
        if (flags & MAP_RESILIENT_MEDIA) {
                alloc_flags |= VM_FLAGS_RESILIENT_MEDIA;
        }

#ifndef CONFIG_EMBEDDED
        if (flags & MAP_32BIT) {
                if (csr_check(CSR_ALLOW_UNTRUSTED_KEXTS) == 0 ||
                    IOTaskHasEntitlement(current_task(), MAP_32BIT_ENTITLEMENT)) {
                        vmk_flags.vmkf_32bit_map_va = TRUE;
                } else {
                        error = EPERM;
                        goto bad;
                }
        }
#endif

        /*
         * Lookup/allocate object.
         */
        if (handle == NULL) {
                control = NULL;
#ifdef notyet
/* Hmm .. */
#if defined(VM_PROT_READ_IS_EXEC)
                if (prot & VM_PROT_READ) {
                        prot |= VM_PROT_EXECUTE;
                }
                if (maxprot & VM_PROT_READ) {
                        maxprot |= VM_PROT_EXECUTE;
                }
#endif
#endif

#if 3777787
                if (prot & (VM_PROT_EXECUTE | VM_PROT_WRITE)) {
                        prot |= VM_PROT_READ;
                }
                if (maxprot & (VM_PROT_EXECUTE | VM_PROT_WRITE)) {
                        maxprot |= VM_PROT_READ;
                }
#endif  /* radar 3777787 */
map_anon_retry:
                result = vm_map_enter_mem_object(user_map,
                    &user_addr, user_size,
                    0, alloc_flags, vmk_flags,
                    tag,
                    IPC_PORT_NULL, 0, FALSE,
                    prot, maxprot,
                    (flags & MAP_SHARED) ?
                    VM_INHERIT_SHARE :
                    VM_INHERIT_DEFAULT);

                /* If a non-binding address was specified for this anonymous
                 * mapping, retry the mapping with a zero base
                 * in the event the mapping operation failed due to
                 * lack of space between the address and the map's maximum.
                 */
                if ((result == KERN_NO_SPACE) && ((flags & MAP_FIXED) == 0) && user_addr && (num_retries++ == 0)) {
                        user_addr = vm_map_page_size(user_map);
                        goto map_anon_retry;
                }
        } else {
                if (vnode_isswap(vp)) {
                        /*
                         * Map swap files with a special pager
                         * that returns obfuscated contents.
                         */
                        control = NULL;
                        pager = swapfile_pager_setup(vp);
                        if (pager != MEMORY_OBJECT_NULL) {
                                control = swapfile_pager_control(pager);
                        }
                } else {
                        control = ubc_getobject(vp, UBC_FLAGS_NONE);
                }

                if (control == NULL) {
                        (void)vnode_put(vp);
                        error = ENOMEM;
                        goto bad;
                }

                /*
                 *  Set credentials:
                 *      FIXME: if we're writing the file we need a way to
                 *      ensure that someone doesn't replace our R/W creds
                 *      with ones that only work for read.
                 */

                ubc_setthreadcred(vp, p, current_thread());
                docow = FALSE;
                if ((flags & (MAP_ANON | MAP_SHARED)) == 0) {
                        docow = TRUE;
                }

#ifdef notyet
/* Hmm .. */
#if defined(VM_PROT_READ_IS_EXEC)
                if (prot & VM_PROT_READ) {
                        prot |= VM_PROT_EXECUTE;
                }
                if (maxprot & VM_PROT_READ) {
                        maxprot |= VM_PROT_EXECUTE;
                }
#endif
#endif /* notyet */

#if 3777787
                if (prot & (VM_PROT_EXECUTE | VM_PROT_WRITE)) {
                        prot |= VM_PROT_READ;
                }
                if (maxprot & (VM_PROT_EXECUTE | VM_PROT_WRITE)) {
                        maxprot |= VM_PROT_READ;
                }
#endif  /* radar 3777787 */

map_file_retry:
                if (flags & MAP_RESILIENT_CODESIGN) {
                        if (prot & (VM_PROT_WRITE | VM_PROT_EXECUTE)) {
                                assert(!mapanon);
                                vnode_put(vp);
                                error = EPERM;
                                goto bad;
                        }
                        /* strictly limit access to "prot" */
                        maxprot &= prot;
                }

                vm_object_offset_t end_pos = 0;
                if (os_add_overflow(user_size, file_pos, &end_pos)) {
                        vnode_put(vp);
                        error = EINVAL;
                        goto bad;
                }

                result = vm_map_enter_mem_object_control(user_map,
                    &user_addr, user_size,
                    0, alloc_flags, vmk_flags,
                    tag,
                    control, file_pos,
                    docow, prot, maxprot,
                    (flags & MAP_SHARED) ?
                    VM_INHERIT_SHARE :
                    VM_INHERIT_DEFAULT);

                /* If a non-binding address was specified for this file backed
                 * mapping, retry the mapping with a zero base
                 * in the event the mapping operation failed due to
                 * lack of space between the address and the map's maximum.
                 */
                if ((result == KERN_NO_SPACE) && ((flags & MAP_FIXED) == 0) && user_addr && (num_retries++ == 0)) {
                        user_addr = vm_map_page_size(user_map);
                        goto map_file_retry;
                }
        }

        if (!mapanon) {
                (void)vnode_put(vp);
        }

        switch (result) {
        case KERN_SUCCESS:
                *retval = user_addr + pageoff;
                error = 0;
                break;
        case KERN_INVALID_ADDRESS:
        case KERN_NO_SPACE:
                error =  ENOMEM;
                break;
        case KERN_PROTECTION_FAILURE:
                error =  EACCES;
                break;
        default:
                error =  EINVAL;
                break;
        }
bad:
        if (pager != MEMORY_OBJECT_NULL) {
                /*
                 * Release the reference on the pager.
                 * If the mapping was successful, it now holds
                 * an extra reference.
                 */
                memory_object_deallocate(pager);
        }
        if (fpref) {
                fp_drop(p, fd, fp, 0);
        }

        KERNEL_DEBUG_CONSTANT((BSDDBG_CODE(DBG_BSD_SC_EXTENDED_INFO, SYS_mmap) | DBG_FUNC_NONE), fd, (uint32_t)(*retval), (uint32_t)user_size, error, 0);
#ifndef CONFIG_EMBEDDED
        KERNEL_DEBUG_CONSTANT((BSDDBG_CODE(DBG_BSD_SC_EXTENDED_INFO2, SYS_mmap) | DBG_FUNC_NONE), (uint32_t)(*retval >> 32), (uint32_t)(user_size >> 32),
            (uint32_t)(file_pos >> 32), (uint32_t)file_pos, 0);
#endif
        return error;
}

int
msync(__unused proc_t p, struct msync_args *uap, int32_t *retval)
{
        __pthread_testcancel(1);
        return msync_nocancel(p, (struct msync_nocancel_args *)uap, retval);
}

int
msync_nocancel(__unused proc_t p, struct msync_nocancel_args *uap, __unused int32_t *retval)
{
        mach_vm_offset_t addr;
        mach_vm_size_t size;
        int flags;
        vm_map_t user_map;
        int rv;
        vm_sync_t sync_flags = 0;

        user_map = current_map();
        addr = (mach_vm_offset_t) uap->addr;
        size = (mach_vm_size_t) uap->len;
#ifndef CONFIG_EMBEDDED
        KERNEL_DEBUG_CONSTANT((BSDDBG_CODE(DBG_BSD_SC_EXTENDED_INFO, SYS_msync) | DBG_FUNC_NONE), (uint32_t)(addr >> 32), (uint32_t)(size >> 32), 0, 0, 0);
#endif
        if (mach_vm_range_overflows(addr, size)) {
                return EINVAL;
        }
        if (addr & vm_map_page_mask(user_map)) {
                /* UNIX SPEC: user address is not page-aligned, return EINVAL */
                return EINVAL;
        }
        if (size == 0) {
                /*
                 * We cannot support this properly without maintaining
                 * list all mmaps done. Cannot use vm_map_entry as they could be
                 * split or coalesced by indepenedant actions. So instead of
                 * inaccurate results, lets just return error as invalid size
                 * specified
                 */
                return EINVAL; /* XXX breaks posix apps */
        }

        flags = uap->flags;
        /* disallow contradictory flags */
        if ((flags & (MS_SYNC | MS_ASYNC)) == (MS_SYNC | MS_ASYNC)) {
                return EINVAL;
        }

        if (flags & MS_KILLPAGES) {
                sync_flags |= VM_SYNC_KILLPAGES;
        }
        if (flags & MS_DEACTIVATE) {
                sync_flags |= VM_SYNC_DEACTIVATE;
        }
        if (flags & MS_INVALIDATE) {
                sync_flags |= VM_SYNC_INVALIDATE;
        }

        if (!(flags & (MS_KILLPAGES | MS_DEACTIVATE))) {
                if (flags & MS_ASYNC) {
                        sync_flags |= VM_SYNC_ASYNCHRONOUS;
                } else {
                        sync_flags |= VM_SYNC_SYNCHRONOUS;
                }
        }

        sync_flags |= VM_SYNC_CONTIGUOUS;       /* complain if holes */

        rv = mach_vm_msync(user_map, addr, size, sync_flags);

        switch (rv) {
        case KERN_SUCCESS:
                break;
        case KERN_INVALID_ADDRESS:      /* hole in region being sync'ed */
                return ENOMEM;
        case KERN_FAILURE:
                return EIO;
        default:
                return EINVAL;
        }
        return 0;
}


int
munmap(__unused proc_t p, struct munmap_args *uap, __unused int32_t *retval)
{
        mach_vm_offset_t        user_addr;
        mach_vm_size_t          user_size;
        kern_return_t           result;
        vm_map_t                user_map;

        user_map = current_map();
        user_addr = (mach_vm_offset_t) uap->addr;
        user_size = (mach_vm_size_t) uap->len;

        AUDIT_ARG(addr, user_addr);
        AUDIT_ARG(len, user_size);

        if (user_addr & vm_map_page_mask(user_map)) {
                /* UNIX SPEC: user address is not page-aligned, return EINVAL */
                return EINVAL;
        }

        if (mach_vm_range_overflows(user_addr, user_size)) {
                return EINVAL;
        }

        if (user_size == 0) {
                /* UNIX SPEC: size is 0, return EINVAL */
                return EINVAL;
        }

        result = mach_vm_deallocate(user_map, user_addr, user_size);
        if (result != KERN_SUCCESS) {
                return EINVAL;
        }
        return 0;
}

int
mprotect(__unused proc_t p, struct mprotect_args *uap, __unused int32_t *retval)
{
        vm_prot_t prot;
        mach_vm_offset_t        user_addr;
        mach_vm_size_t  user_size;
        kern_return_t   result;
        vm_map_t        user_map;
#if CONFIG_MACF
        int error;
#endif

        AUDIT_ARG(addr, uap->addr);
        AUDIT_ARG(len, uap->len);
        AUDIT_ARG(value32, uap->prot);

        user_map = current_map();
        user_addr = (mach_vm_offset_t) uap->addr;
        user_size = (mach_vm_size_t) uap->len;
        prot = (vm_prot_t)(uap->prot & (VM_PROT_ALL | VM_PROT_TRUSTED | VM_PROT_STRIP_READ));

        if (mach_vm_range_overflows(user_addr, user_size)) {
                return EINVAL;
        }
        if (user_addr & vm_map_page_mask(user_map)) {
                /* UNIX SPEC: user address is not page-aligned, return EINVAL */
                return EINVAL;
        }

#ifdef notyet
/* Hmm .. */
#if defined(VM_PROT_READ_IS_EXEC)
        if (prot & VM_PROT_READ) {
                prot |= VM_PROT_EXECUTE;
        }
#endif
#endif /* notyet */

#if 3936456
        if (prot & (VM_PROT_EXECUTE | VM_PROT_WRITE)) {
                prot |= VM_PROT_READ;
        }
#endif  /* 3936456 */

#if defined(__arm64__)
        if (prot & VM_PROT_STRIP_READ) {
                prot &= ~(VM_PROT_READ | VM_PROT_STRIP_READ);
        }
#endif

#if CONFIG_MACF
        /*
         * The MAC check for mprotect is of limited use for 2 reasons:
         * Without mmap revocation, the caller could have asked for the max
         * protections initially instead of a reduced set, so a mprotect
         * check would offer no new security.
         * It is not possible to extract the vnode from the pager object(s)
         * of the target memory range.
         * However, the MAC check may be used to prevent a process from,
         * e.g., making the stack executable.
         */
        error = mac_proc_check_mprotect(p, user_addr,
            user_size, prot);
        if (error) {
                return error;
        }
#endif

        if (prot & VM_PROT_TRUSTED) {
#if CONFIG_DYNAMIC_CODE_SIGNING
                /* CODE SIGNING ENFORCEMENT - JIT support */
                /* The special protection value VM_PROT_TRUSTED requests that we treat
                 * this page as if it had a valid code signature.
                 * If this is enabled, there MUST be a MAC policy implementing the
                 * mac_proc_check_mprotect() hook above. Otherwise, Codesigning will be
                 * compromised because the check would always succeed and thusly any
                 * process could sign dynamically. */
                result = vm_map_sign(
                        user_map,
                        vm_map_trunc_page(user_addr,
                        vm_map_page_mask(user_map)),
                        vm_map_round_page(user_addr + user_size,
                        vm_map_page_mask(user_map)));
                switch (result) {
                case KERN_SUCCESS:
                        break;
                case KERN_INVALID_ADDRESS:
                        /* UNIX SPEC: for an invalid address range, return ENOMEM */
                        return ENOMEM;
                default:
                        return EINVAL;
                }
#else
                return ENOTSUP;
#endif
        }
        prot &= ~VM_PROT_TRUSTED;

        result = mach_vm_protect(user_map, user_addr, user_size,
            FALSE, prot);
        switch (result) {
        case KERN_SUCCESS:
                return 0;
        case KERN_PROTECTION_FAILURE:
                return EACCES;
        case KERN_INVALID_ADDRESS:
                /* UNIX SPEC: for an invalid address range, return ENOMEM */
                return ENOMEM;
        }
        return EINVAL;
}


int
minherit(__unused proc_t p, struct minherit_args *uap, __unused int32_t *retval)
{
        mach_vm_offset_t addr;
        mach_vm_size_t size;
        vm_inherit_t inherit;
        vm_map_t        user_map;
        kern_return_t   result;

        AUDIT_ARG(addr, uap->addr);
        AUDIT_ARG(len, uap->len);
        AUDIT_ARG(value32, uap->inherit);

        addr = (mach_vm_offset_t)uap->addr;
        size = (mach_vm_size_t)uap->len;
        inherit = uap->inherit;
        if (mach_vm_range_overflows(addr, size)) {
                return EINVAL;
        }
        user_map = current_map();
        result = mach_vm_inherit(user_map, addr, size,
            inherit);
        switch (result) {
        case KERN_SUCCESS:
                return 0;
        case KERN_PROTECTION_FAILURE:
                return EACCES;
        }
        return EINVAL;
}

int
madvise(__unused proc_t p, struct madvise_args *uap, __unused int32_t *retval)
{
        vm_map_t user_map;
        mach_vm_offset_t start;
        mach_vm_size_t size;
        vm_behavior_t new_behavior;
        kern_return_t   result;

        /*
         * Since this routine is only advisory, we default to conservative
         * behavior.
         */
        switch (uap->behav) {
        case MADV_RANDOM:
                new_behavior = VM_BEHAVIOR_RANDOM;
                break;
        case MADV_SEQUENTIAL:
                new_behavior = VM_BEHAVIOR_SEQUENTIAL;
                break;
        case MADV_NORMAL:
                new_behavior = VM_BEHAVIOR_DEFAULT;
                break;
        case MADV_WILLNEED:
                new_behavior = VM_BEHAVIOR_WILLNEED;
                break;
        case MADV_DONTNEED:
                new_behavior = VM_BEHAVIOR_DONTNEED;
                break;
        case MADV_FREE:
                new_behavior = VM_BEHAVIOR_FREE;
                break;
        case MADV_ZERO_WIRED_PAGES:
                new_behavior = VM_BEHAVIOR_ZERO_WIRED_PAGES;
                break;
        case MADV_FREE_REUSABLE:
                new_behavior = VM_BEHAVIOR_REUSABLE;
                break;
        case MADV_FREE_REUSE:
                new_behavior = VM_BEHAVIOR_REUSE;
                break;
        case MADV_CAN_REUSE:
                new_behavior = VM_BEHAVIOR_CAN_REUSE;
                break;
        case MADV_PAGEOUT:
#if MACH_ASSERT
                new_behavior = VM_BEHAVIOR_PAGEOUT;
                break;
#else /* MACH_ASSERT */
                return ENOTSUP;
#endif /* MACH_ASSERT */
        default:
                return EINVAL;
        }

        start = (mach_vm_offset_t) uap->addr;
        size = (mach_vm_size_t) uap->len;
        if (mach_vm_range_overflows(start, size)) {
                return EINVAL;
        }
#if __arm64__
        if (start == 0 &&
            size != 0 &&
            (uap->behav == MADV_FREE ||
            uap->behav == MADV_FREE_REUSABLE)) {
                printf("** FOURK_COMPAT: %d[%s] "
                    "failing madvise(0x%llx,0x%llx,%s)\n",
                    p->p_pid, p->p_comm, start, size,
                    ((uap->behav == MADV_FREE_REUSABLE)
                    ? "MADV_FREE_REUSABLE"
                    : "MADV_FREE"));
                DTRACE_VM3(fourk_compat_madvise,
                    uint64_t, start,
                    uint64_t, size,
                    int, uap->behav);
                return EINVAL;
        }
#endif /* __arm64__ */

        user_map = current_map();

        result = mach_vm_behavior_set(user_map, start, size, new_behavior);
        switch (result) {
        case KERN_SUCCESS:
                return 0;
        case KERN_INVALID_ADDRESS:
                return EINVAL;
        case KERN_NO_SPACE:
                return ENOMEM;
        }

        return EINVAL;
}

int
mincore(__unused proc_t p, struct mincore_args *uap, __unused int32_t *retval)
{
        mach_vm_offset_t addr = 0, first_addr = 0, end = 0, cur_end = 0;
        vm_map_t map = VM_MAP_NULL;
        user_addr_t vec = 0;
        int error = 0;
        int lastvecindex = 0;
        int mincoreinfo = 0;
        int pqueryinfo = 0;
        unsigned int pqueryinfo_vec_size = 0;
        vm_page_info_basic_t info = NULL;
        mach_msg_type_number_t count = 0;
        char *kernel_vec = NULL;
        uint64_t req_vec_size_pages = 0, cur_vec_size_pages = 0, vecindex = 0;
        kern_return_t kr = KERN_SUCCESS;

        map = current_map();

        /*
         * Make sure that the addresses presented are valid for user
         * mode.
         */
        first_addr = addr = vm_map_trunc_page(uap->addr,
            vm_map_page_mask(map));
        end = vm_map_round_page(uap->addr + uap->len,
            vm_map_page_mask(map));

        if (end < addr) {
                return EINVAL;
        }

        if (end == addr) {
                return 0;
        }

        /*
         * We are going to loop through the whole 'req_vec_size' pages
         * range in chunks of 'cur_vec_size'.
         */

        req_vec_size_pages = (end - addr) >> PAGE_SHIFT;
        cur_vec_size_pages = MIN(req_vec_size_pages, (MAX_PAGE_RANGE_QUERY >> PAGE_SHIFT));

        kernel_vec = (void*) _MALLOC(cur_vec_size_pages * sizeof(char), M_TEMP, M_WAITOK | M_ZERO);

        if (kernel_vec == NULL) {
                return ENOMEM;
        }

        /*
         * Address of byte vector
         */
        vec = uap->vec;

        pqueryinfo_vec_size = cur_vec_size_pages * sizeof(struct vm_page_info_basic);
        info = (void*) _MALLOC(pqueryinfo_vec_size, M_TEMP, M_WAITOK);

        if (info == NULL) {
                FREE(kernel_vec, M_TEMP);
                return ENOMEM;
        }

        while (addr < end) {
                cur_end = addr + (cur_vec_size_pages * PAGE_SIZE_64);

                count =  VM_PAGE_INFO_BASIC_COUNT;
                kr = vm_map_page_range_info_internal(map,
                    addr,
                    cur_end,
                    VM_PAGE_INFO_BASIC,
                    (vm_page_info_t) info,
                    &count);

                assert(kr == KERN_SUCCESS);

                /*
                 * Do this on a map entry basis so that if the pages are not
                 * in the current processes address space, we can easily look
                 * up the pages elsewhere.
                 */
                lastvecindex = -1;
                for (; addr < cur_end; addr += PAGE_SIZE) {
                        pqueryinfo = info[lastvecindex + 1].disposition;

                        mincoreinfo = 0;

                        if (pqueryinfo & VM_PAGE_QUERY_PAGE_PRESENT) {
                                mincoreinfo |= MINCORE_INCORE;
                        }
                        if (pqueryinfo & VM_PAGE_QUERY_PAGE_REF) {
                                mincoreinfo |= MINCORE_REFERENCED;
                        }
                        if (pqueryinfo & VM_PAGE_QUERY_PAGE_DIRTY) {
                                mincoreinfo |= MINCORE_MODIFIED;
                        }
                        if (pqueryinfo & VM_PAGE_QUERY_PAGE_PAGED_OUT) {
                                mincoreinfo |= MINCORE_PAGED_OUT;
                        }
                        if (pqueryinfo & VM_PAGE_QUERY_PAGE_COPIED) {
                                mincoreinfo |= MINCORE_COPIED;
                        }
                        if ((pqueryinfo & VM_PAGE_QUERY_PAGE_EXTERNAL) == 0) {
                                mincoreinfo |= MINCORE_ANONYMOUS;
                        }
                        /*
                         * calculate index into user supplied byte vector
                         */
                        vecindex = (addr - first_addr) >> PAGE_SHIFT;
                        kernel_vec[vecindex] = (char)mincoreinfo;
                        lastvecindex = vecindex;
                }


                assert(vecindex == (cur_vec_size_pages - 1));

                error = copyout(kernel_vec, vec, cur_vec_size_pages * sizeof(char) /* a char per page */);

                if (error) {
                        break;
                }

                /*
                 * For the next chunk, we'll need:
                 * - bump the location in the user buffer for our next disposition.
                 * - new length
                 * - starting address
                 */
                vec += cur_vec_size_pages * sizeof(char);
                req_vec_size_pages = (end - addr) >> PAGE_SHIFT;
                cur_vec_size_pages = MIN(req_vec_size_pages, (MAX_PAGE_RANGE_QUERY >> PAGE_SHIFT));

                first_addr = addr;
        }

        FREE(kernel_vec, M_TEMP);
        FREE(info, M_TEMP);

        if (error) {
                return EFAULT;
        }

        return 0;
}

int
mlock(__unused proc_t p, struct mlock_args *uap, __unused int32_t *retvalval)
{
        vm_map_t user_map;
        vm_map_offset_t addr;
        vm_map_size_t size, pageoff;
        kern_return_t   result;

        AUDIT_ARG(addr, uap->addr);
        AUDIT_ARG(len, uap->len);

        addr = (vm_map_offset_t) uap->addr;
        size = (vm_map_size_t)uap->len;

        if (vm_map_range_overflows(addr, size)) {
                return EINVAL;
        }

        if (size == 0) {
                return 0;
        }

        user_map = current_map();
        pageoff = (addr & vm_map_page_mask(user_map));
        addr -= pageoff;
        size = vm_map_round_page(size + pageoff, vm_map_page_mask(user_map));

        /* have to call vm_map_wire directly to pass "I don't know" protections */
        result = vm_map_wire_kernel(user_map, addr, addr + size, VM_PROT_NONE, VM_KERN_MEMORY_MLOCK, TRUE);

        if (result == KERN_RESOURCE_SHORTAGE) {
                return EAGAIN;
        } else if (result == KERN_PROTECTION_FAILURE) {
                return EACCES;
        } else if (result != KERN_SUCCESS) {
                return ENOMEM;
        }

        return 0;       /* KERN_SUCCESS */
}

int
munlock(__unused proc_t p, struct munlock_args *uap, __unused int32_t *retval)
{
        mach_vm_offset_t addr;
        mach_vm_size_t size;
        vm_map_t user_map;
        kern_return_t   result;

        AUDIT_ARG(addr, uap->addr);
        AUDIT_ARG(len, uap->len);

        addr = (mach_vm_offset_t) uap->addr;
        size = (mach_vm_size_t)uap->len;
        user_map = current_map();
        if (mach_vm_range_overflows(addr, size)) {
                return EINVAL;
        }
        /* JMM - need to remove all wirings by spec - this just removes one */
        result = mach_vm_wire_kernel(host_priv_self(), user_map, addr, size, VM_PROT_NONE, VM_KERN_MEMORY_MLOCK);
        return result == KERN_SUCCESS ? 0 : ENOMEM;
}


int
mlockall(__unused proc_t p, __unused struct mlockall_args *uap, __unused int32_t *retval)
{
        return ENOSYS;
}

int
munlockall(__unused proc_t p, __unused struct munlockall_args *uap, __unused int32_t *retval)
{
        return ENOSYS;
}

#if CONFIG_CODE_DECRYPTION
int
mremap_encrypted(__unused struct proc *p, struct mremap_encrypted_args *uap, __unused int32_t *retval)
{
        mach_vm_offset_t    user_addr;
        mach_vm_size_t      user_size;
        kern_return_t       result;
        vm_map_t    user_map;
        uint32_t    cryptid;
        cpu_type_t  cputype;
        cpu_subtype_t       cpusubtype;
        pager_crypt_info_t  crypt_info;
        const char * cryptname = 0;
        char *vpath;
        int len, ret;
        struct proc_regioninfo_internal pinfo;
        vnode_t vp;
        uintptr_t vnodeaddr;
        uint32_t vid;

        AUDIT_ARG(addr, uap->addr);
        AUDIT_ARG(len, uap->len);

        user_map = current_map();
        user_addr = (mach_vm_offset_t) uap->addr;
        user_size = (mach_vm_size_t) uap->len;

        cryptid = uap->cryptid;
        cputype = uap->cputype;
        cpusubtype = uap->cpusubtype;

        if (mach_vm_range_overflows(user_addr, user_size)) {
                return EINVAL;
        }
        if (user_addr & vm_map_page_mask(user_map)) {
                /* UNIX SPEC: user address is not page-aligned, return EINVAL */
                return EINVAL;
        }

        switch (cryptid) {
        case 0:
                /* not encrypted, just an empty load command */
                return 0;
        case 1:
                cryptname = "com.apple.unfree";
                break;
        case 0x10:
                /* some random cryptid that you could manually put into
                 * your binary if you want NULL */
                cryptname = "com.apple.null";
                break;
        default:
                return EINVAL;
        }

        if (NULL == text_crypter_create) {
                return ENOTSUP;
        }

        ret = fill_procregioninfo_onlymappedvnodes( proc_task(p), user_addr, &pinfo, &vnodeaddr, &vid);
        if (ret == 0 || !vnodeaddr) {
                /* No really, this returns 0 if the memory address is not backed by a file */
                return EINVAL;
        }

        vp = (vnode_t)vnodeaddr;
        if ((vnode_getwithvid(vp, vid)) == 0) {
                MALLOC_ZONE(vpath, char *, MAXPATHLEN, M_NAMEI, M_WAITOK);
                if (vpath == NULL) {
                        vnode_put(vp);
                        return ENOMEM;
                }

                len = MAXPATHLEN;
                ret = vn_getpath(vp, vpath, &len);
                if (ret) {
                        FREE_ZONE(vpath, MAXPATHLEN, M_NAMEI);
                        vnode_put(vp);
                        return ret;
                }

                vnode_put(vp);
        } else {
                return EINVAL;
        }

#if 0
        kprintf("%s vpath %s cryptid 0x%08x cputype 0x%08x cpusubtype 0x%08x range 0x%016llx size 0x%016llx\n",
            __FUNCTION__, vpath, cryptid, cputype, cpusubtype, (uint64_t)user_addr, (uint64_t)user_size);
#endif

        /* set up decrypter first */
        crypt_file_data_t crypt_data = {
                .filename = vpath,
                .cputype = cputype,
                .cpusubtype = cpusubtype
        };
        result = text_crypter_create(&crypt_info, cryptname, (void*)&crypt_data);
#if VM_MAP_DEBUG_APPLE_PROTECT
        if (vm_map_debug_apple_protect) {
                printf("APPLE_PROTECT: %d[%s] map %p [0x%llx:0x%llx] %s(%s) -> 0x%x\n",
                    p->p_pid, p->p_comm,
                    user_map,
                    (uint64_t) user_addr,
                    (uint64_t) (user_addr + user_size),
                    __FUNCTION__, vpath, result);
        }
#endif /* VM_MAP_DEBUG_APPLE_PROTECT */
        FREE_ZONE(vpath, MAXPATHLEN, M_NAMEI);

        if (result) {
                printf("%s: unable to create decrypter %s, kr=%d\n",
                    __FUNCTION__, cryptname, result);
                if (result == kIOReturnNotPrivileged) {
                        /* text encryption returned decryption failure */
                        return EPERM;
                } else {
                        return ENOMEM;
                }
        }

        /* now remap using the decrypter */
        vm_object_offset_t crypto_backing_offset;
        crypto_backing_offset = -1; /* i.e. use map entry's offset */
        result = vm_map_apple_protected(user_map,
            user_addr,
            user_addr + user_size,
            crypto_backing_offset,
            &crypt_info);
        if (result) {
                printf("%s: mapping failed with %d\n", __FUNCTION__, result);
        }

        if (result) {
                return EPERM;
        }
        return 0;
}
#endif /* CONFIG_CODE_DECRYPTION */