xnu-6153.81.5.tar.gz

[apple/xnu.git] / bsd / vfs / vfs_lookup.c

diff --git a/bsd/vfs/vfs_lookup.c b/bsd/vfs/vfs_lookup.c
index 55b86f9e65efb6d812f20172cd9d96266c57bfeb..85d47741ee3c9fea99a9709b9d45e49bd584b61d 100644 (file)
--- a/bsd/vfs/vfs_lookup.c
+++ b/bsd/vfs/vfs_lookup.c
@@ -2,7 +2,7 @@
  * Copyright (c) 2000-2015 Apple Inc. All rights reserved.
  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  * Copyright (c) 2000-2015 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
  * 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


@@ -11,10 +11,10 @@
  * 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.
  * 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.
  * 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,
  * 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,


@@ -22,7 +22,7 @@
  * 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.
  * 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 */
  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
 /* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */


@@ -85,7 +85,7 @@
 #include <sys/filedesc.h>
 #include <sys/proc_internal.h>
 #include <sys/kdebug.h>
 #include <sys/filedesc.h>
 #include <sys/proc_internal.h>
 #include <sys/kdebug.h>

-#include <sys/unistd.h>                /* For _PC_NAME_MAX */
+#include <sys/unistd.h>         /* For _PC_NAME_MAX */

 #include <sys/uio_internal.h>
 #include <sys/kauth.h>
 #include <kern/kalloc.h>
 #include <sys/uio_internal.h>
 #include <sys/kauth.h>
 #include <kern/kalloc.h>


@@ -95,6 +95,8 @@
 #include <security/mac_framework.h>
 #endif
 
 #include <security/mac_framework.h>
 #endif
 

+#include <sys/paths.h>
+

 #if NAMEDRSRCFORK
 #include <sys/xattr.h>
 #endif
 #if NAMEDRSRCFORK
 #include <sys/xattr.h>
 #endif


@@ -105,24 +107,22 @@
 #define VOLFS_MIN_PATH_LEN  9
 
 
 #define VOLFS_MIN_PATH_LEN  9
 
 

-static void kdebug_lookup(struct vnode *dp, struct componentname *cnp);
-

 #if CONFIG_VOLFS
 static int vfs_getrealpath(const char * path, char * realpath, size_t bufsize, vfs_context_t ctx);
 #define MAX_VOLFS_RESTARTS 5
 #endif
 
 #if CONFIG_VOLFS
 static int vfs_getrealpath(const char * path, char * realpath, size_t bufsize, vfs_context_t ctx);
 #define MAX_VOLFS_RESTARTS 5
 #endif
 

-static int             lookup_traverse_mountpoints(struct nameidata *ndp, struct componentname *cnp, vnode_t dp, int vbusyflags, vfs_context_t ctx);
-static int             lookup_handle_symlink(struct nameidata *ndp, vnode_t *new_dp, vfs_context_t ctx);
-static int             lookup_authorize_search(vnode_t dp, struct componentname *cnp, int dp_authorized_in_cache, vfs_context_t ctx);
-static void            lookup_consider_update_cache(vnode_t dvp, vnode_t vp, struct componentname *cnp, int nc_generation);
-static int             lookup_handle_found_vnode(struct nameidata *ndp, struct componentname *cnp, int rdonly, 
-                       int vbusyflags, int *keep_going, int nc_generation,
-                       int wantparent, int atroot, vfs_context_t ctx);
-static int             lookup_handle_emptyname(struct nameidata *ndp, struct componentname *cnp, int wantparent);
+static int              lookup_traverse_mountpoints(struct nameidata *ndp, struct componentname *cnp, vnode_t dp, int vbusyflags, vfs_context_t ctx);
+static int              handle_symlink_for_namei(struct nameidata *ndp, vnode_t *new_dp, vfs_context_t ctx);
+static int              lookup_authorize_search(vnode_t dp, struct componentname *cnp, int dp_authorized_in_cache, vfs_context_t ctx);
+static void             lookup_consider_update_cache(vnode_t dvp, vnode_t vp, struct componentname *cnp, int nc_generation);
+static int              lookup_handle_found_vnode(struct nameidata *ndp, struct componentname *cnp, int rdonly,
+    int vbusyflags, int *keep_going, int nc_generation,
+    int wantparent, int atroot, vfs_context_t ctx);
+static int              lookup_handle_emptyname(struct nameidata *ndp, struct componentname *cnp, int wantparent);

 
 #if NAMEDRSRCFORK
 
 #if NAMEDRSRCFORK

-static int             lookup_handle_rsrc_fork(vnode_t dp, struct nameidata *ndp, struct componentname *cnp, int wantparent, vfs_context_t ctx);
+static int              lookup_handle_rsrc_fork(vnode_t dp, struct nameidata *ndp, struct componentname *cnp, int wantparent, vfs_context_t ctx);

 #endif
 
 
 #endif
 
 


@@ -165,10 +165,12 @@ static int                lookup_handle_rsrc_fork(vnode_t dp, struct nameidata *ndp, struct co
 int
 namei(struct nameidata *ndp)
 {
 int
 namei(struct nameidata *ndp)
 {

-       struct filedesc *fdp;   /* pointer to file descriptor state */
-       struct vnode *dp;       /* the directory we are searching */
+       struct filedesc *fdp;   /* pointer to file descriptor state */
+       struct vnode *dp;       /* the directory we are searching */
+       struct vnode *rootdir_with_usecount = NULLVP;
+       struct vnode *startdir_with_usecount = NULLVP;

        struct vnode *usedvp = ndp->ni_dvp;  /* store pointer to vp in case we must loop due to
        struct vnode *usedvp = ndp->ni_dvp;  /* store pointer to vp in case we must loop due to

-                                                                                       heavy vnode pressure */
+                                             *                                          heavy vnode pressure */

        u_long cnpflags = ndp->ni_cnd.cn_flags; /* store in case we have to restore after loop */
        int error;
        struct componentname *cnp = &ndp->ni_cnd;
        u_long cnpflags = ndp->ni_cnd.cn_flags; /* store in case we have to restore after loop */
        int error;
        struct componentname *cnp = &ndp->ni_cnd;


@@ -187,12 +189,15 @@ namei(struct nameidata *ndp)
        fdp = p->p_fd;
 
 #if DIAGNOSTIC
        fdp = p->p_fd;
 
 #if DIAGNOSTIC

-       if (!vfs_context_ucred(ctx) || !p)
-               panic ("namei: bad cred/proc");
-       if (cnp->cn_nameiop & (~OPMASK))
-               panic ("namei: nameiop contaminated with flags");
-       if (cnp->cn_flags & OPMASK)
-               panic ("namei: flags contaminated with nameiops");
+       if (!vfs_context_ucred(ctx) || !p) {
+               panic("namei: bad cred/proc");
+       }
+       if (cnp->cn_nameiop & (~OPMASK)) {
+               panic("namei: nameiop contaminated with flags");
+       }
+       if (cnp->cn_flags & OPMASK) {
+               panic("namei: flags contaminated with nameiops");
+       }

 #endif
 
        /*
 #endif
 
        /*


@@ -209,10 +214,11 @@ namei(struct nameidata *ndp)
 
                ndp->ni_flag &= ~(NAMEI_CONTLOOKUP);
 
 
                ndp->ni_flag &= ~(NAMEI_CONTLOOKUP);
 

-               error = lookup_handle_found_vnode(ndp, &ndp->ni_cnd, rdonly, vbusyflags, 
-                               &keep_going, ndp->ni_ncgeneration, wantparent, 0, ctx);
-               if (error)
+               error = lookup_handle_found_vnode(ndp, &ndp->ni_cnd, rdonly, vbusyflags,
+                   &keep_going, ndp->ni_ncgeneration, wantparent, 0, ctx);
+               if (error) {

                        goto out_drop;
                        goto out_drop;

+               }

                if (keep_going) {
                        if ((cnp->cn_flags & ISSYMLINK) == 0) {
                                panic("We need to keep going on a continued lookup, but for vp type %d (tag %d)\n", ndp->ni_vp->v_type, ndp->ni_vp->v_tag);
                if (keep_going) {
                        if ((cnp->cn_flags & ISSYMLINK) == 0) {
                                panic("We need to keep going on a continued lookup, but for vp type %d (tag %d)\n", ndp->ni_vp->v_type, ndp->ni_vp->v_tag);


@@ -221,7 +227,6 @@ namei(struct nameidata *ndp)
                }
 
                return 0;
                }
 
                return 0;

-

        }
 
 vnode_recycled:
        }
 
 vnode_recycled:


@@ -236,19 +241,19 @@ vnode_recycled:
        }
 #if LP64_DEBUG
        if ((UIO_SEG_IS_USER_SPACE(ndp->ni_segflg) == 0)
        }
 #if LP64_DEBUG
        if ((UIO_SEG_IS_USER_SPACE(ndp->ni_segflg) == 0)

-               && (ndp->ni_segflg != UIO_SYSSPACE)
-               && (ndp->ni_segflg != UIO_SYSSPACE32)) {
-               panic("%s :%d - invalid ni_segflg\n", __FILE__, __LINE__); 
+           && (ndp->ni_segflg != UIO_SYSSPACE)
+           && (ndp->ni_segflg != UIO_SYSSPACE32)) {
+               panic("%s :%d - invalid ni_segflg\n", __FILE__, __LINE__);

        }
 #endif /* LP64_DEBUG */
 
 retry_copy:
        if (UIO_SEG_IS_USER_SPACE(ndp->ni_segflg)) {
                error = copyinstr(ndp->ni_dirp, cnp->cn_pnbuf,
        }
 #endif /* LP64_DEBUG */
 
 retry_copy:
        if (UIO_SEG_IS_USER_SPACE(ndp->ni_segflg)) {
                error = copyinstr(ndp->ni_dirp, cnp->cn_pnbuf,

-                           cnp->cn_pnlen, &bytes_copied);
+                   cnp->cn_pnlen, &bytes_copied);

        } else {
                error = copystr(CAST_DOWN(void *, ndp->ni_dirp), cnp->cn_pnbuf,
        } else {
                error = copystr(CAST_DOWN(void *, ndp->ni_dirp), cnp->cn_pnbuf,

-                           cnp->cn_pnlen, &bytes_copied);
+                   cnp->cn_pnlen, &bytes_copied);

        }
        if (error == ENAMETOOLONG && !(cnp->cn_flags & HASBUF)) {
                MALLOC_ZONE(cnp->cn_pnbuf, caddr_t, MAXPATHLEN, M_NAMEI, M_WAITOK);
        }
        if (error == ENAMETOOLONG && !(cnp->cn_flags & HASBUF)) {
                MALLOC_ZONE(cnp->cn_pnbuf, caddr_t, MAXPATHLEN, M_NAMEI, M_WAITOK);


@@ -260,11 +265,12 @@ retry_copy:
                cnp->cn_flags |= HASBUF;
                cnp->cn_pnlen = MAXPATHLEN;
                bytes_copied = 0;
                cnp->cn_flags |= HASBUF;
                cnp->cn_pnlen = MAXPATHLEN;
                bytes_copied = 0;

-               
+

                goto retry_copy;
        }
                goto retry_copy;
        }

-       if (error)
-               goto error_out;
+       if (error) {
+               goto error_out;
+       }

        ndp->ni_pathlen = bytes_copied;
        bytes_copied = 0;
 
        ndp->ni_pathlen = bytes_copied;
        bytes_copied = 0;
 


@@ -275,11 +281,12 @@ retry_copy:
         * component. Note: the FS may still consult the cache,
         * but can apply rules to validate the results.
         */
         * component. Note: the FS may still consult the cache,
         * but can apply rules to validate the results.
         */

-       if (proc_is_forcing_hfs_case_sensitivity(p))
+       if (proc_is_forcing_hfs_case_sensitivity(p)) {

                cnp->cn_flags |= CN_SKIPNAMECACHE;
                cnp->cn_flags |= CN_SKIPNAMECACHE;

+       }

 
 #if CONFIG_VOLFS
 
 #if CONFIG_VOLFS

-       /*
+       /*

         * Check for legacy volfs style pathnames.
         *
         * For compatibility reasons we currently allow these paths,
         * Check for legacy volfs style pathnames.
         *
         * For compatibility reasons we currently allow these paths,


@@ -291,21 +298,21 @@ retry_copy:
            cnp->cn_pnbuf[2] == 'v' &&
            cnp->cn_pnbuf[3] == 'o' &&
            cnp->cn_pnbuf[4] == 'l' &&
            cnp->cn_pnbuf[2] == 'v' &&
            cnp->cn_pnbuf[3] == 'o' &&
            cnp->cn_pnbuf[4] == 'l' &&

-           cnp->cn_pnbuf[5] == '/' ) {
+           cnp->cn_pnbuf[5] == '/') {

                char * realpath;
                int realpath_err;
                /* Attempt to resolve a legacy volfs style pathname. */
                MALLOC_ZONE(realpath, caddr_t, MAXPATHLEN, M_NAMEI, M_WAITOK);
                if (realpath) {
                char * realpath;
                int realpath_err;
                /* Attempt to resolve a legacy volfs style pathname. */
                MALLOC_ZONE(realpath, caddr_t, MAXPATHLEN, M_NAMEI, M_WAITOK);
                if (realpath) {

-                       /* 
+                       /*

                         * We only error out on the ENAMETOOLONG cases where we know that
                         * vfs_getrealpath translation succeeded but the path could not fit into
                         * MAXPATHLEN characters.  In other failure cases, we may be dealing with a path
                         * that legitimately looks like /.vol/1234/567 and is not meant to be translated
                         */
                         * We only error out on the ENAMETOOLONG cases where we know that
                         * vfs_getrealpath translation succeeded but the path could not fit into
                         * MAXPATHLEN characters.  In other failure cases, we may be dealing with a path
                         * that legitimately looks like /.vol/1234/567 and is not meant to be translated
                         */

-                       if ((realpath_err= vfs_getrealpath(&cnp->cn_pnbuf[6], realpath, MAXPATHLEN, ctx))) {
+                       if ((realpath_err = vfs_getrealpath(&cnp->cn_pnbuf[6], realpath, MAXPATHLEN, ctx))) {

                                FREE_ZONE(realpath, MAXPATHLEN, M_NAMEI);
                                FREE_ZONE(realpath, MAXPATHLEN, M_NAMEI);

-                               if (realpath_err == ENOSPC || realpath_err == ENAMETOOLONG){
+                               if (realpath_err == ENOSPC || realpath_err == ENAMETOOLONG) {

                                        error = ENAMETOOLONG;
                                        goto error_out;
                                }
                                        error = ENAMETOOLONG;
                                        goto error_out;
                                }


@@ -324,10 +331,12 @@ retry_copy:
 
 #if CONFIG_AUDIT
        /* If we are auditing the kernel pathname, save the user pathname */
 
 #if CONFIG_AUDIT
        /* If we are auditing the kernel pathname, save the user pathname */

-       if (cnp->cn_flags & AUDITVNPATH1)
-               AUDIT_ARG(upath, ut->uu_cdir, cnp->cn_pnbuf, ARG_UPATH1); 
-       if (cnp->cn_flags & AUDITVNPATH2)
-               AUDIT_ARG(upath, ut->uu_cdir, cnp->cn_pnbuf, ARG_UPATH2); 
+       if (cnp->cn_flags & AUDITVNPATH1) {
+               AUDIT_ARG(upath, ut->uu_cdir, cnp->cn_pnbuf, ARG_UPATH1);
+       }
+       if (cnp->cn_flags & AUDITVNPATH2) {
+               AUDIT_ARG(upath, ut->uu_cdir, cnp->cn_pnbuf, ARG_UPATH2);
+       }

 #endif /* CONFIG_AUDIT */
 
        /*
 #endif /* CONFIG_AUDIT */
 
        /*


@@ -341,31 +350,130 @@ retry_copy:
 
        /*
         * determine the starting point for the translation.
 
        /*
         * determine the starting point for the translation.

+        *
+        * We may need to upto 2 usecounts on vnodes before starting the translation
+        * We need to have a usecount on the root directory for the process
+        * for the entire duration of the lookup. This is because symlink
+        * translation can restart translation at / if a symlink is encountered.
+        *
+        * For the duration of this lookup at rootdir for this lookup is the one
+        * we fetch now under the proc_fdlock even the if the proc rootdir changes
+        * once we let go of the proc_fdlock.
+        *
+        * In the future we may consider holding off a chroot till we complete
+        * in progress lookups.
+        *
+        * If the starting directory is not the process rootdir then we need
+        * a usecount on the starting directory as well for the duration of the
+        * lookup.
+        *
+        * Getting an addtional usecount involves first getting an iocount under
+        * the lock that ensures that a usecount is on the directory. Once we
+        * get an iocount we can release the lock and we will be free to get a
+        * usecount without the vnode getting recycled. Once we get the usecount
+        * we can release the icoount which we used to get our usecount.
+        */
+       proc_fdlock(p);
+       if (!(fdp->fd_flags & FD_CHROOT)) {
+               ndp->ni_rootdir = rootvnode;
+       } else {
+               ndp->ni_rootdir = fdp->fd_rdir;
+       }
+
+       if (!ndp->ni_rootdir) {
+               if (!(fdp->fd_flags & FD_CHROOT)) {
+                       proc_fdunlock(p);
+                       printf("rootvnode is not set\n");
+               } else {
+                       proc_fdunlock(p);
+                       /* This should be a panic */
+                       printf("fdp->fd_rdir is not set\n");
+               }
+               error = ENOENT;
+               goto error_out;
+       }
+
+       /*
+        * We have the proc_fdlock here so we still have a usecount
+        * on ndp->ni_rootdir.
+        *
+        * However we need to get our own usecount on it in order to
+        * ensure that the vnode isn't recycled to something else.
+        *
+        * Note : It's fine if the vnode is force reclaimed but with
+        * a usecount it won't be reused until we release the reference.
+        *
+        * In order to get that usecount however, we need to first
+        * get non blocking iocount since we'll be doing this under
+        * the proc_fdlock.

         */
         */

-       if ((ndp->ni_rootdir = fdp->fd_rdir) == NULLVP) {
-               if ( !(fdp->fd_flags & FD_CHROOT))
-                       ndp->ni_rootdir = rootvnode;
+       if (vnode_get(ndp->ni_rootdir) != 0) {
+               proc_fdunlock(p);
+               error = ENOENT;
+               goto error_out;

        }
        }

+
+       proc_fdunlock(p);
+
+       /* Now we can safely get our own ref on ni_rootdir */
+       error = vnode_ref_ext(ndp->ni_rootdir, O_EVTONLY, 0);
+       vnode_put(ndp->ni_rootdir);
+       if (error) {
+               ndp->ni_rootdir = NULLVP;
+               goto error_out;
+       }
+
+       rootdir_with_usecount = ndp->ni_rootdir;
+

        cnp->cn_nameptr = cnp->cn_pnbuf;
 
        ndp->ni_usedvp = NULLVP;
 
        cnp->cn_nameptr = cnp->cn_pnbuf;
 
        ndp->ni_usedvp = NULLVP;
 

+       bool dp_needs_put = false;

        if (*(cnp->cn_nameptr) == '/') {
        if (*(cnp->cn_nameptr) == '/') {

-               while (*(cnp->cn_nameptr) == '/') {
-                       cnp->cn_nameptr++;
+               while (*(cnp->cn_nameptr) == '/') {
+                       cnp->cn_nameptr++;

                        ndp->ni_pathlen--;
                }
                dp = ndp->ni_rootdir;
        } else if (cnp->cn_flags & USEDVP) {
                        ndp->ni_pathlen--;
                }
                dp = ndp->ni_rootdir;
        } else if (cnp->cn_flags & USEDVP) {

-               dp = ndp->ni_dvp;
+               dp = ndp->ni_dvp;

                ndp->ni_usedvp = dp;
                ndp->ni_usedvp = dp;

-       } else
-               dp = vfs_context_cwd(ctx);
+       } else {
+               dp = vfs_context_get_cwd(ctx);
+               if (dp) {
+                       dp_needs_put = true;
+               }
+       }

 
        if (dp == NULLVP || (dp->v_lflag & VL_DEAD)) {
 
        if (dp == NULLVP || (dp->v_lflag & VL_DEAD)) {

-               error = ENOENT;
+               if (dp_needs_put) {
+                       vnode_put(dp);
+                       dp_needs_put = false;
+               }
+               dp = NULLVP;
+               error = ENOENT;

                goto error_out;
        }
                goto error_out;
        }

+
+       if (dp != rootdir_with_usecount) {
+               error = vnode_ref_ext(dp, O_EVTONLY, 0);
+               if (error) {
+                       if (dp_needs_put) {
+                               vnode_put(dp);
+                               dp_needs_put = false;
+                       }
+                       dp = NULLVP;
+                       goto error_out;
+               }
+               startdir_with_usecount = dp;
+       }
+
+       if (dp_needs_put) {
+               vnode_put(dp);
+               dp_needs_put = false;
+       }
+

        ndp->ni_dvp = NULLVP;
        ndp->ni_vp  = NULLVP;
 
        ndp->ni_dvp = NULLVP;
        ndp->ni_vp  = NULLVP;
 


@@ -386,8 +494,9 @@ retry_copy:
 #endif
 
                ndp->ni_startdir = dp;
 #endif
 
                ndp->ni_startdir = dp;

+               dp = NULLVP;

 
 

-               if ( (error = lookup(ndp)) ) {
+               if ((error = lookup(ndp))) {

                        goto error_out;
                }
 
                        goto error_out;
                }
 


@@ -395,15 +504,46 @@ retry_copy:
                 * Check for symbolic link
                 */
                if ((cnp->cn_flags & ISSYMLINK) == 0) {
                 * Check for symbolic link
                 */
                if ((cnp->cn_flags & ISSYMLINK) == 0) {

-                       return (0);
+                       if (startdir_with_usecount) {
+                               vnode_rele_ext(startdir_with_usecount, O_EVTONLY, 0);
+                               startdir_with_usecount = NULLVP;
+                       }
+                       if (rootdir_with_usecount) {
+                               vnode_rele_ext(rootdir_with_usecount, O_EVTONLY, 0);
+                               rootdir_with_usecount = NULLVP;
+                       }
+                       return 0;

                }
 
 continue_symlink:
                }
 
 continue_symlink:

-               /* Gives us a new path to process, and a starting dir */
-               error = lookup_handle_symlink(ndp, &dp, ctx);
+               /*
+                * Gives us a new path to process, and a starting dir (with an iocount).
+                * The iocount is needed to take a usecount on the vnode returned
+                * (if it is not a vnode we already have a usecount on).
+                */
+               error = handle_symlink_for_namei(ndp, &dp, ctx);

                if (error != 0) {
                        break;
                }
                if (error != 0) {
                        break;
                }

+
+               if (dp == ndp->ni_rootdir && startdir_with_usecount) {
+                       vnode_rele_ext(startdir_with_usecount, O_EVTONLY, 0);
+                       startdir_with_usecount = NULLVP;
+               } else if (dp != startdir_with_usecount) {
+                       if (startdir_with_usecount) {
+                               vnode_rele_ext(startdir_with_usecount, O_EVTONLY, 0);
+                               startdir_with_usecount = NULLVP;
+                       }
+                       error = vnode_ref_ext(dp, O_EVTONLY, 0);
+                       if (error) {
+                               vnode_put(dp);
+                               dp = NULLVP;
+                               goto error_out;
+                       }
+                       startdir_with_usecount = dp;
+               }
+               /* iocount not required on dp anymore */
+               vnode_put(dp);

        }
        /*
         * only come here if we fail to handle a SYMLINK...
        }
        /*
         * only come here if we fail to handle a SYMLINK...


@@ -412,12 +552,14 @@ continue_symlink:
         * up in the lookup routine
         */
 out_drop:
         * up in the lookup routine
         */
 out_drop:

-       if (ndp->ni_dvp)
-               vnode_put(ndp->ni_dvp);
-       if (ndp->ni_vp)
-               vnode_put(ndp->ni_vp);
- error_out:
-       if ( (cnp->cn_flags & HASBUF) ) {
+       if (ndp->ni_dvp) {
+               vnode_put(ndp->ni_dvp);
+       }
+       if (ndp->ni_vp) {
+               vnode_put(ndp->ni_vp);
+       }
+error_out:
+       if ((cnp->cn_flags & HASBUF)) {

                cnp->cn_flags &= ~HASBUF;
                FREE_ZONE(cnp->cn_pnbuf, cnp->cn_pnlen, M_NAMEI);
        }
                cnp->cn_flags &= ~HASBUF;
                FREE_ZONE(cnp->cn_pnbuf, cnp->cn_pnlen, M_NAMEI);
        }


@@ -425,27 +567,36 @@ out_drop:
        ndp->ni_vp = NULLVP;
        ndp->ni_dvp = NULLVP;
 
        ndp->ni_vp = NULLVP;
        ndp->ni_dvp = NULLVP;
 

+       if (startdir_with_usecount) {
+               vnode_rele_ext(startdir_with_usecount, O_EVTONLY, 0);
+               startdir_with_usecount = NULLVP;
+       }
+       if (rootdir_with_usecount) {
+               vnode_rele_ext(rootdir_with_usecount, O_EVTONLY, 0);
+               rootdir_with_usecount = NULLVP;
+       }
+

 #if CONFIG_VOLFS
        /*
 #if CONFIG_VOLFS
        /*

-        * Deal with volfs fallout.  
+        * Deal with volfs fallout.

         *
         * At this point, if we were originally given a volfs path that
         * looks like /.vol/123/456, then we would have had to convert it into
         * a full path.  Assuming that part worked properly, we will now attempt
         *
         * At this point, if we were originally given a volfs path that
         * looks like /.vol/123/456, then we would have had to convert it into
         * a full path.  Assuming that part worked properly, we will now attempt

-        * to conduct a lookup of the item in the namespace.  Under normal 
-        * circumstances, if a user looked up /tmp/foo and it was not there, it 
-        * would be permissible to return ENOENT.  
+        * to conduct a lookup of the item in the namespace.  Under normal
+        * circumstances, if a user looked up /tmp/foo and it was not there, it
+        * would be permissible to return ENOENT.

         *
         * However, we may not want to do that here.  Specifically, the volfs path
         * uniquely identifies a certain item in the namespace regardless of where it
         * lives.  If the item has moved in between the time we constructed the
         * path and now, when we're trying to do a lookup/authorization on the full
         *
         * However, we may not want to do that here.  Specifically, the volfs path
         * uniquely identifies a certain item in the namespace regardless of where it
         * lives.  If the item has moved in between the time we constructed the
         * path and now, when we're trying to do a lookup/authorization on the full

-        * path, we may have gotten an ENOENT.  
+        * path, we may have gotten an ENOENT.
+        *
+        * At this point we can no longer tell if the path no longer exists
+        * or if the item in question no longer exists. It could have been renamed
+        * away, in which case the /.vol identifier is still valid.

         *
         *

-        * At this point we can no longer tell if the path no longer exists 
-        * or if the item in question no longer exists. It could have been renamed 
-        * away, in which case the /.vol identifier is still valid. 
-        * 

         * Do this dance a maximum of MAX_VOLFS_RESTARTS times.
         */
        if ((error == ENOENT) && (ndp->ni_cnd.cn_flags & CN_VOLFSPATH)) {
         * Do this dance a maximum of MAX_VOLFS_RESTARTS times.
         */
        if ((error == ENOENT) && (ndp->ni_cnd.cn_flags & CN_VOLFSPATH)) {


@@ -456,19 +607,19 @@ out_drop:
        }
 #endif
 
        }
 #endif
 

-       if (error == ERECYCLE){
-               /* vnode was recycled underneath us. re-drive lookup to start at 
-                  the beginning again, since recycling invalidated last lookup*/
+       if (error == ERECYCLE) {
+               /* vnode was recycled underneath us. re-drive lookup to start at
+                *  the beginning again, since recycling invalidated last lookup*/

                ndp->ni_cnd.cn_flags = cnpflags;
                ndp->ni_dvp = usedvp;
                goto vnode_recycled;
        }
 
 
                ndp->ni_cnd.cn_flags = cnpflags;
                ndp->ni_dvp = usedvp;
                goto vnode_recycled;
        }
 
 

-       return (error);
+       return error;

 }
 
 }
 

-int            
+int

 namei_compound_available(vnode_t dp, struct nameidata *ndp)
 {
        if ((ndp->ni_flag & NAMEI_COMPOUNDOPEN) != 0) {
 namei_compound_available(vnode_t dp, struct nameidata *ndp)
 {
        if ((ndp->ni_flag & NAMEI_COMPOUNDOPEN) != 0) {


@@ -489,20 +640,22 @@ lookup_authorize_search(vnode_t dp, struct componentname *cnp, int dp_authorized
 
        if (!dp_authorized_in_cache) {
                error = vnode_authorize(dp, NULL, KAUTH_VNODE_SEARCH, ctx);
 
        if (!dp_authorized_in_cache) {
                error = vnode_authorize(dp, NULL, KAUTH_VNODE_SEARCH, ctx);

-               if (error)
+               if (error) {

                        return error;
                        return error;

+               }

        }
 #if CONFIG_MACF
        error = mac_vnode_check_lookup(ctx, dp, cnp);
        }
 #if CONFIG_MACF
        error = mac_vnode_check_lookup(ctx, dp, cnp);

-       if (error)
+       if (error) {

                return error;
                return error;

+       }

 #endif /* CONFIG_MACF */
 
        return 0;
 }
 
 #endif /* CONFIG_MACF */
 
        return 0;
 }
 

-static void 
-lookup_consider_update_cache(vnode_t dvp, vnode_t vp, struct componentname *cnp, int nc_generation) 
+static void
+lookup_consider_update_cache(vnode_t dvp, vnode_t vp, struct componentname *cnp, int nc_generation)

 {
        int isdot_or_dotdot;
        isdot_or_dotdot = (cnp->cn_namelen == 1 && cnp->cn_nameptr[0] == '.') || (cnp->cn_flags & ISDOTDOT);
 {
        int isdot_or_dotdot;
        isdot_or_dotdot = (cnp->cn_namelen == 1 && cnp->cn_nameptr[0] == '.') || (cnp->cn_flags & ISDOTDOT);


@@ -511,16 +664,19 @@ lookup_consider_update_cache(vnode_t dvp, vnode_t vp, struct componentname *cnp,
                int  update_flags = 0;
 
                if (isdot_or_dotdot == 0) {
                int  update_flags = 0;
 
                if (isdot_or_dotdot == 0) {

-                       if (vp->v_name == NULL)
+                       if (vp->v_name == NULL) {

                                update_flags |= VNODE_UPDATE_NAME;
                                update_flags |= VNODE_UPDATE_NAME;

-                       if (dvp != NULLVP && vp->v_parent == NULLVP)
+                       }
+                       if (dvp != NULLVP && vp->v_parent == NULLVP) {

                                update_flags |= VNODE_UPDATE_PARENT;
                                update_flags |= VNODE_UPDATE_PARENT;

+                       }

 
 

-                       if (update_flags)
+                       if (update_flags) {

                                vnode_update_identity(vp, dvp, cnp->cn_nameptr, cnp->cn_namelen, cnp->cn_hash, update_flags);
                                vnode_update_identity(vp, dvp, cnp->cn_nameptr, cnp->cn_namelen, cnp->cn_hash, update_flags);

+                       }

                }
        }
                }
        }

-       if ( (cnp->cn_flags & MAKEENTRY) && (vp->v_flag & VNCACHEABLE) && LIST_FIRST(&vp->v_nclinks) == NULL) {
+       if ((cnp->cn_flags & MAKEENTRY) && (vp->v_flag & VNCACHEABLE) && LIST_FIRST(&vp->v_nclinks) == NULL) {

                /*
                 * missing from name cache, but should
                 * be in it... this can happen if volfs
                /*
                 * missing from name cache, but should
                 * be in it... this can happen if volfs


@@ -534,16 +690,16 @@ lookup_consider_update_cache(vnode_t dvp, vnode_t vp, struct componentname *cnp,
                 * rechecked behind the name cache lock, but if it
                 * already fails to match, no need to go any further
                 */
                 * rechecked behind the name cache lock, but if it
                 * already fails to match, no need to go any further
                 */

-               if (dvp != NULLVP && (nc_generation == dvp->v_nc_generation) && (!isdot_or_dotdot))
+               if (dvp != NULLVP && (nc_generation == dvp->v_nc_generation) && (!isdot_or_dotdot)) {

                        cache_enter_with_gen(dvp, vp, cnp, nc_generation);
                        cache_enter_with_gen(dvp, vp, cnp, nc_generation);

+               }

        }
        }

-

 }
 
 #if NAMEDRSRCFORK
 /*
  * Can change ni_dvp and ni_vp.  On success, returns with iocounts on stream vnode (always) and
 }
 
 #if NAMEDRSRCFORK
 /*
  * Can change ni_dvp and ni_vp.  On success, returns with iocounts on stream vnode (always) and

- * data fork if requested.  On failure, returns with iocount data fork (always) and its parent directory 
+ * data fork if requested.  On failure, returns with iocount data fork (always) and its parent directory

  * (if one was provided).
  */
 static int
  * (if one was provided).
  */
 static int


@@ -559,39 +715,40 @@ lookup_handle_rsrc_fork(vnode_t dp, struct nameidata *ndp, struct componentname
                goto out;
        }
        switch (cnp->cn_nameiop) {
                goto out;
        }
        switch (cnp->cn_nameiop) {

-               case DELETE:
-                       if (cnp->cn_flags & CN_ALLOWRSRCFORK) {
-                               nsop = NS_DELETE;
-                       } else {
-                               error = EPERM;
-                               goto out;
-                       }
-                       break;
-               case CREATE:
-                       if (cnp->cn_flags & CN_ALLOWRSRCFORK) {
-                               nsop = NS_CREATE;
-                       } else {
-                               error = EPERM;
-                               goto out;
-                       }
-                       break;
-               case LOOKUP:
-                       /* Make sure our lookup of "/..namedfork/rsrc" is allowed. */
-                       if (cnp->cn_flags & CN_ALLOWRSRCFORK) {
-                               nsop = NS_OPEN;
-                       } else {
-                               error = EPERM;
-                               goto out;
-                       }
-                       break;
-               default:
+       case DELETE:
+               if (cnp->cn_flags & CN_ALLOWRSRCFORK) {
+                       nsop = NS_DELETE;
+               } else {
+                       error = EPERM;
+                       goto out;
+               }
+               break;
+       case CREATE:
+               if (cnp->cn_flags & CN_ALLOWRSRCFORK) {
+                       nsop = NS_CREATE;
+               } else {

                        error = EPERM;
                        goto out;
                        error = EPERM;
                        goto out;

+               }
+               break;
+       case LOOKUP:
+               /* Make sure our lookup of "/..namedfork/rsrc" is allowed. */
+               if (cnp->cn_flags & CN_ALLOWRSRCFORK) {
+                       nsop = NS_OPEN;
+               } else {
+                       error = EPERM;
+                       goto out;
+               }
+               break;
+       default:
+               error = EPERM;
+               goto out;

        }
 
        nsflags = 0;
        }
 
        nsflags = 0;

-       if (cnp->cn_flags & CN_RAW_ENCRYPTED)
+       if (cnp->cn_flags & CN_RAW_ENCRYPTED) {

                nsflags |= NS_GETRAWENCRYPTED;
                nsflags |= NS_GETRAWENCRYPTED;

+       }

 
        /* Ask the file system for the resource fork. */
        error = vnode_getnamedstream(dp, &svp, XATTR_RESOURCEFORK_NAME, nsop, nsflags, ctx);
 
        /* Ask the file system for the resource fork. */
        error = vnode_getnamedstream(dp, &svp, XATTR_RESOURCEFORK_NAME, nsop, nsflags, ctx);


@@ -599,7 +756,7 @@ lookup_handle_rsrc_fork(vnode_t dp, struct nameidata *ndp, struct componentname
        /* During a create, it OK for stream vnode to be missing. */
        if (error == ENOATTR || error == ENOENT) {
                error = (nsop == NS_CREATE) ? 0 : ENOENT;
        /* During a create, it OK for stream vnode to be missing. */
        if (error == ENOATTR || error == ENOENT) {
                error = (nsop == NS_CREATE) ? 0 : ENOENT;

-       }               
+       }

        if (error) {
                goto out;
        }
        if (error) {
                goto out;
        }


@@ -616,7 +773,21 @@ lookup_handle_rsrc_fork(vnode_t dp, struct nameidata *ndp, struct componentname
 
        /* Restore the truncated pathname buffer (for audits). */
        if (ndp->ni_pathlen == 1 && ndp->ni_next[0] == '\0') {
 
        /* Restore the truncated pathname buffer (for audits). */
        if (ndp->ni_pathlen == 1 && ndp->ni_next[0] == '\0') {

-               ndp->ni_next[0] = '/';
+               /*
+                * While we replaced only '/' with '\0' and would ordinarily
+                * need to just switch that back, the buffer in which we did
+                * this may not be what the pathname buffer is now when symlinks
+                * are involved. If we just restore the "/" we will make the
+                * string not terminated anymore, so be safe and restore the
+                * entire suffix.
+                */
+               strncpy(ndp->ni_next, _PATH_RSRCFORKSPEC, sizeof(_PATH_RSRCFORKSPEC));
+               cnp->cn_nameptr = ndp->ni_next + 1;
+               cnp->cn_namelen = sizeof(_PATH_RSRCFORKSPEC) - 1;
+               ndp->ni_next += cnp->cn_namelen;
+               if (ndp->ni_next[0] != '\0') {
+                       panic("Incorrect termination of path in %s", __FUNCTION__);
+               }

        }
        cnp->cn_flags  &= ~MAKEENTRY;
 
        }
        cnp->cn_flags  &= ~MAKEENTRY;
 


@@ -628,22 +799,22 @@ out:
 
 /*
  * iocounts in:
 
 /*
  * iocounts in:

- *     --One on ni_vp.  One on ni_dvp if there is more path, or we didn't come through the
- *     cache, or we came through the cache and the caller doesn't want the parent.
+ *      --One on ni_vp.  One on ni_dvp if there is more path, or we didn't come through the
+ *      cache, or we came through the cache and the caller doesn't want the parent.

  *
  * iocounts out:
  *     --Leaves us in the correct state for the next step, whatever that might be.
  *     --If we find a symlink, returns with iocounts on both ni_vp and ni_dvp.
  *     --If we are to look up another component, then we have an iocount on ni_vp and
  *
  * iocounts out:
  *     --Leaves us in the correct state for the next step, whatever that might be.
  *     --If we find a symlink, returns with iocounts on both ni_vp and ni_dvp.
  *     --If we are to look up another component, then we have an iocount on ni_vp and

- *     nothing else.  
+ *     nothing else.

  *     --If we are done, returns an iocount on ni_vp, and possibly on ni_dvp depending on nameidata flags.
  *     --In the event of an error, may return with ni_dvp NULL'ed out (in which case, iocount
  *     was dropped).
  */
  *     --If we are done, returns an iocount on ni_vp, and possibly on ni_dvp depending on nameidata flags.
  *     --In the event of an error, may return with ni_dvp NULL'ed out (in which case, iocount
  *     was dropped).
  */

-static int             
-lookup_handle_found_vnode(struct nameidata *ndp, struct componentname *cnp, int rdonly, 
-               int vbusyflags, int *keep_going, int nc_generation,
-               int wantparent, int atroot, vfs_context_t ctx)
+static int
+lookup_handle_found_vnode(struct nameidata *ndp, struct componentname *cnp, int rdonly,
+    int vbusyflags, int *keep_going, int nc_generation,
+    int wantparent, int atroot, vfs_context_t ctx)

 {
        vnode_t dp;
        int error;
 {
        vnode_t dp;
        int error;


@@ -687,8 +858,9 @@ lookup_handle_found_vnode(struct nameidata *ndp, struct componentname *cnp, int
 #if CONFIG_MACF
        if (vfs_flags(vnode_mount(dp)) & MNT_MULTILABEL) {
                error = vnode_label(vnode_mount(dp), NULL, dp, NULL, 0, ctx);
 #if CONFIG_MACF
        if (vfs_flags(vnode_mount(dp)) & MNT_MULTILABEL) {
                error = vnode_label(vnode_mount(dp), NULL, dp, NULL, 0, ctx);

-               if (error)
+               if (error) {

                        goto out;
                        goto out;

+               }

        }
 #endif
 
        }
 #endif
 


@@ -699,7 +871,7 @@ lookup_handle_found_vnode(struct nameidata *ndp, struct componentname *cnp, int
            ((cnp->cn_flags & FOLLOW) || (ndp->ni_flag & NAMEI_TRAILINGSLASH) || *ndp->ni_next == '/')) {
                cnp->cn_flags |= ISSYMLINK;
                *keep_going = 1;
            ((cnp->cn_flags & FOLLOW) || (ndp->ni_flag & NAMEI_TRAILINGSLASH) || *ndp->ni_next == '/')) {
                cnp->cn_flags |= ISSYMLINK;
                *keep_going = 1;

-               return (0);
+               return 0;

        }
 
        /*
        }
 
        /*


@@ -711,15 +883,15 @@ lookup_handle_found_vnode(struct nameidata *ndp, struct componentname *cnp, int
                        goto out;
                }
                ndp->ni_flag &= ~(NAMEI_TRAILINGSLASH);
                        goto out;
                }
                ndp->ni_flag &= ~(NAMEI_TRAILINGSLASH);

-       } 
+       }

 
 #if NAMEDSTREAMS
 
 #if NAMEDSTREAMS

-       /* 
+       /*

         * Deny namei/lookup requests to resolve paths that point to shadow files.
         * Access to shadow files must be conducted by explicit calls to VNOP_LOOKUP
         * directly, and not use lookup/namei
         */
         * Deny namei/lookup requests to resolve paths that point to shadow files.
         * Access to shadow files must be conducted by explicit calls to VNOP_LOOKUP
         * directly, and not use lookup/namei
         */

-       if (vnode_isshadow (dp)) {
+       if (vnode_isshadow(dp)) {

                error = ENOENT;
                goto out;
        }
                error = ENOENT;
                goto out;
        }


@@ -730,7 +902,7 @@ nextname:
         * Not a symbolic link.  If more pathname,
         * continue at next component, else return.
         *
         * Not a symbolic link.  If more pathname,
         * continue at next component, else return.
         *

-        * Definitely have a dvp if there's another slash 
+        * Definitely have a dvp if there's another slash

         */
        if (*ndp->ni_next == '/') {
                cnp->cn_nameptr = ndp->ni_next + 1;
         */
        if (*ndp->ni_next == '/') {
                cnp->cn_nameptr = ndp->ni_next + 1;


@@ -751,7 +923,7 @@ nextname:
                *keep_going = 1;
                return 0;
        }
                *keep_going = 1;
                return 0;
        }

-                                 
+

        /*
         * Disallow directory write attempts on read-only file systems.
         */
        /*
         * Disallow directory write attempts on read-only file systems.
         */


@@ -760,17 +932,17 @@ nextname:
                error = EROFS;
                goto out;
        }
                error = EROFS;
                goto out;
        }

-       
+

        /* If SAVESTART is set, we should have a dvp */
        if (cnp->cn_flags & SAVESTART) {
        /* If SAVESTART is set, we should have a dvp */
        if (cnp->cn_flags & SAVESTART) {

-               /*      
+               /*

                 * note that we already hold a reference
                 * on both dp and ni_dvp, but for some reason
                 * can't get another one... in this case we
                 * need to do vnode_put on dp in 'bad2'
                 */
                 * note that we already hold a reference
                 * on both dp and ni_dvp, but for some reason
                 * can't get another one... in this case we
                 * need to do vnode_put on dp in 'bad2'
                 */

-               if ( (vnode_get(ndp->ni_dvp)) ) {
-                       error = ENOENT;
+               if ((vnode_get(ndp->ni_dvp))) {
+                       error = ENOENT;

                        goto out;
                }
                ndp->ni_startdir = ndp->ni_dvp;
                        goto out;
                }
                ndp->ni_startdir = ndp->ni_dvp;


@@ -780,10 +952,11 @@ nextname:
                ndp->ni_dvp = NULLVP;
        }
 
                ndp->ni_dvp = NULLVP;
        }
 

-       if (cnp->cn_flags & AUDITVNPATH1)
+       if (cnp->cn_flags & AUDITVNPATH1) {

                AUDIT_ARG(vnpath, dp, ARG_VNODE1);
                AUDIT_ARG(vnpath, dp, ARG_VNODE1);

-       else if (cnp->cn_flags & AUDITVNPATH2)
+       } else if (cnp->cn_flags & AUDITVNPATH2) {

                AUDIT_ARG(vnpath, dp, ARG_VNODE2);
                AUDIT_ARG(vnpath, dp, ARG_VNODE2);

+       }

 
 #if NAMEDRSRCFORK
        /*
 
 #if NAMEDRSRCFORK
        /*


@@ -791,32 +964,34 @@ nextname:
         */
        if ((cnp->cn_flags & CN_WANTSRSRCFORK) && (dp != NULLVP)) {
                error = lookup_handle_rsrc_fork(dp, ndp, cnp, wantparent, ctx);
         */
        if ((cnp->cn_flags & CN_WANTSRSRCFORK) && (dp != NULLVP)) {
                error = lookup_handle_rsrc_fork(dp, ndp, cnp, wantparent, ctx);

-               if (error != 0)
+               if (error != 0) {

                        goto out;
                        goto out;

+               }

 
                dp = ndp->ni_vp;
        }
 #endif
 
                dp = ndp->ni_vp;
        }
 #endif

-       if (kdebug_enable)
-               kdebug_lookup(ndp->ni_vp, cnp);
+       if (kdebug_enable) {
+               kdebug_lookup(ndp->ni_vp, cnp);
+       }

 
        return 0;
 
 emptyname:
        error = lookup_handle_emptyname(ndp, cnp, wantparent);
 
        return 0;
 
 emptyname:
        error = lookup_handle_emptyname(ndp, cnp, wantparent);

-       if (error != 0) 
+       if (error != 0) {

                goto out;
                goto out;

+       }

 
        return 0;
 out:
        return error;
 
        return 0;
 out:
        return error;

-

 }
 
 /*
  * Comes in iocount on ni_vp.  May overwrite ni_dvp, but doesn't interpret incoming value.
  */
 }
 
 /*
  * Comes in iocount on ni_vp.  May overwrite ni_dvp, but doesn't interpret incoming value.
  */

-static int 
+static int

 lookup_handle_emptyname(struct nameidata *ndp, struct componentname *cnp, int wantparent)
 {
        vnode_t dp;
 lookup_handle_emptyname(struct nameidata *ndp, struct componentname *cnp, int wantparent)
 {
        vnode_t dp;


@@ -837,14 +1012,14 @@ lookup_handle_emptyname(struct nameidata *ndp, struct componentname *cnp, int wa
                goto out;
        }
        if (wantparent) {
                goto out;
        }
        if (wantparent) {

-               /*      
+               /*

                 * note that we already hold a reference
                 * on dp, but for some reason can't
                 * get another one... in this case we
                 * need to do vnode_put on dp in 'bad'
                 */
                 * note that we already hold a reference
                 * on dp, but for some reason can't
                 * get another one... in this case we
                 * need to do vnode_put on dp in 'bad'
                 */

-               if ( (vnode_get(dp)) ) {
-                       error = ENOENT;
+               if ((vnode_get(dp))) {
+                       error = ENOENT;

                        goto out;
                }
                ndp->ni_dvp = dp;
                        goto out;
                }
                ndp->ni_dvp = dp;


@@ -854,12 +1029,14 @@ lookup_handle_emptyname(struct nameidata *ndp, struct componentname *cnp, int wa
        ndp->ni_next = cnp->cn_nameptr;
        ndp->ni_vp = dp;
 
        ndp->ni_next = cnp->cn_nameptr;
        ndp->ni_vp = dp;
 

-       if (cnp->cn_flags & AUDITVNPATH1)
+       if (cnp->cn_flags & AUDITVNPATH1) {

                AUDIT_ARG(vnpath, dp, ARG_VNODE1);
                AUDIT_ARG(vnpath, dp, ARG_VNODE1);

-       else if (cnp->cn_flags & AUDITVNPATH2)
+       } else if (cnp->cn_flags & AUDITVNPATH2) {

                AUDIT_ARG(vnpath, dp, ARG_VNODE2);
                AUDIT_ARG(vnpath, dp, ARG_VNODE2);

-       if (cnp->cn_flags & SAVESTART)
+       }
+       if (cnp->cn_flags & SAVESTART) {

                panic("lookup: SAVESTART");
                panic("lookup: SAVESTART");

+       }

 
        return 0;
 out:
 
        return 0;
 out:


@@ -886,7 +1063,7 @@ out:
  * the target is returned locked, otherwise it is returned unlocked.
  * When creating or renaming and LOCKPARENT is specified, the target may not
  * be ".".  When deleting and LOCKPARENT is specified, the target may be ".".
  * the target is returned locked, otherwise it is returned unlocked.
  * When creating or renaming and LOCKPARENT is specified, the target may not
  * be ".".  When deleting and LOCKPARENT is specified, the target may be ".".

- * 
+ *

  * Overall outline of lookup:
  *
  * dirloop:
  * Overall outline of lookup:
  *
  * dirloop:


@@ -924,12 +1101,12 @@ out:
 int
 lookup(struct nameidata *ndp)
 {
 int
 lookup(struct nameidata *ndp)
 {

-       char    *cp;            /* pointer into pathname argument */
-       vnode_t         tdp;            /* saved dp */
-       vnode_t         dp;             /* the directory we are searching */
-       int docache = 1;                /* == 0 do not cache last component */
-       int wantparent;                 /* 1 => wantparent or lockparent flag */
-       int rdonly;                     /* lookup read-only flag bit */
+       char    *cp;            /* pointer into pathname argument */
+       vnode_t         tdp;            /* saved dp */
+       vnode_t         dp;             /* the directory we are searching */
+       int docache = 1;                /* == 0 do not cache last component */
+       int wantparent;                 /* 1 => wantparent or lockparent flag */
+       int rdonly;                     /* lookup read-only flag bit */

        int dp_authorized = 0;
        int error = 0;
        struct componentname *cnp = &ndp->ni_cnd;
        int dp_authorized = 0;
        int error = 0;
        struct componentname *cnp = &ndp->ni_cnd;


@@ -944,7 +1121,7 @@ lookup(struct nameidata *ndp)
         * Setup: break out flag bits into variables.
         */
        if (cnp->cn_flags & NOCACHE) {
         * Setup: break out flag bits into variables.
         */
        if (cnp->cn_flags & NOCACHE) {

-               docache = 0;
+               docache = 0;

        }
        wantparent = cnp->cn_flags & (LOCKPARENT | WANTPARENT);
        rdonly = cnp->cn_flags & RDONLY;
        }
        wantparent = cnp->cn_flags & (LOCKPARENT | WANTPARENT);
        rdonly = cnp->cn_flags & RDONLY;


@@ -954,14 +1131,15 @@ lookup(struct nameidata *ndp)
        dp = ndp->ni_startdir;
        ndp->ni_startdir = NULLVP;
 
        dp = ndp->ni_startdir;
        ndp->ni_startdir = NULLVP;
 

-       if ((cnp->cn_flags & CN_NBMOUNTLOOK) != 0)
-                       vbusyflags = LK_NOWAIT;
+       if ((cnp->cn_flags & CN_NBMOUNTLOOK) != 0) {
+               vbusyflags = LK_NOWAIT;
+       }

        cp = cnp->cn_nameptr;
 
        if (*cp == '\0') {
        cp = cnp->cn_nameptr;
 
        if (*cp == '\0') {

-               if ( (vnode_getwithref(dp)) ) {
+               if ((vnode_getwithref(dp))) {

                        dp = NULLVP;
                        dp = NULLVP;

-                       error = ENOENT;
+                       error = ENOENT;

                        goto bad;
                }
                ndp->ni_vp = dp;
                        goto bad;
                }
                ndp->ni_vp = dp;


@@ -972,26 +1150,28 @@ lookup(struct nameidata *ndp)
 
                return 0;
        }
 
                return 0;
        }

-dirloop: 
+dirloop:

        atroot = 0;
        ndp->ni_vp = NULLVP;
 
        atroot = 0;
        ndp->ni_vp = NULLVP;
 

-       if ( (error = cache_lookup_path(ndp, cnp, dp, ctx, &dp_authorized, last_dp)) ) {
+       if ((error = cache_lookup_path(ndp, cnp, dp, ctx, &dp_authorized, last_dp))) {

                dp = NULLVP;
                goto bad;
        }
        if ((cnp->cn_flags & ISLASTCN)) {
                dp = NULLVP;
                goto bad;
        }
        if ((cnp->cn_flags & ISLASTCN)) {

-               if (docache)
-                       cnp->cn_flags |= MAKEENTRY;
-       } else
-               cnp->cn_flags |= MAKEENTRY;
+               if (docache) {
+                       cnp->cn_flags |= MAKEENTRY;
+               }
+       } else {
+               cnp->cn_flags |= MAKEENTRY;
+       }

 
        dp = ndp->ni_dvp;
 
        if (ndp->ni_vp != NULLVP) {
 
        dp = ndp->ni_dvp;
 
        if (ndp->ni_vp != NULLVP) {

-               /*
+               /*

                 * cache_lookup_path returned a non-NULL ni_vp then,
                 * cache_lookup_path returned a non-NULL ni_vp then,

-                * we're guaranteed that the dp is a VDIR, it's 
+                * we're guaranteed that the dp is a VDIR, it's

                 * been authorized, and vp is not ".."
                 *
                 * make sure we don't try to enter the name back into
                 * been authorized, and vp is not ".."
                 *
                 * make sure we don't try to enter the name back into


@@ -999,10 +1179,11 @@ dirloop:
                 * check since we won't have serialized behind whatever
                 * activity is occurring in the FS that caused the purge
                 */
                 * check since we won't have serialized behind whatever
                 * activity is occurring in the FS that caused the purge
                 */

-               if (dp != NULLVP)
-                       nc_generation = dp->v_nc_generation - 1;
+               if (dp != NULLVP) {
+                       nc_generation = dp->v_nc_generation - 1;
+               }

 
 

-               goto returned_from_lookup_path;
+               goto returned_from_lookup_path;

        }
 
        /*
        }
 
        /*


@@ -1015,14 +1196,14 @@ dirloop:
         *    vnode which was mounted on so we take the
         *    .. in the other file system.
         */
         *    vnode which was mounted on so we take the
         *    .. in the other file system.
         */

-       if ( (cnp->cn_flags & ISDOTDOT) ) {
+       if ((cnp->cn_flags & ISDOTDOT)) {

                /*
                 * if this is a chroot'ed process, check if the current
                 * directory is still a subdirectory of the process's
                 * root directory.
                 */
                if (ndp->ni_rootdir && (ndp->ni_rootdir != rootvnode) &&
                /*
                 * if this is a chroot'ed process, check if the current
                 * directory is still a subdirectory of the process's
                 * root directory.
                 */
                if (ndp->ni_rootdir && (ndp->ni_rootdir != rootvnode) &&

-                   dp !=  ndp->ni_rootdir) {
+                   dp != ndp->ni_rootdir) {

                        int sdir_error;
                        int is_subdir = FALSE;
 
                        int sdir_error;
                        int is_subdir = FALSE;
 


@@ -1051,8 +1232,8 @@ dirloop:
                }
 
                for (;;) {
                }
 
                for (;;) {

-                       if (dp == ndp->ni_rootdir || dp == rootvnode) {
-                               ndp->ni_dvp = dp;
+                       if (dp == ndp->ni_rootdir || dp == rootvnode) {
+                               ndp->ni_dvp = dp;

                                ndp->ni_vp = dp;
                                /*
                                 * we're pinned at the root
                                ndp->ni_vp = dp;
                                /*
                                 * we're pinned at the root


@@ -1062,7 +1243,7 @@ dirloop:
                                 * if we fail to get the new reference, we'll
                                 * drop our original down in 'bad'
                                 */
                                 * if we fail to get the new reference, we'll
                                 * drop our original down in 'bad'
                                 */

-                               if ( (vnode_get(dp)) ) {
+                               if ((vnode_get(dp))) {

                                        error = ENOENT;
                                        goto bad;
                                }
                                        error = ENOENT;
                                        goto bad;
                                }


@@ -1070,10 +1251,11 @@ dirloop:
                                goto returned_from_lookup_path;
                        }
                        if ((dp->v_flag & VROOT) == 0 ||
                                goto returned_from_lookup_path;
                        }
                        if ((dp->v_flag & VROOT) == 0 ||

-                           (cnp->cn_flags & NOCROSSMOUNT))
-                               break;
-                       if (dp->v_mount == NULL) {      /* forced umount */
-                               error = EBADF;
+                           (cnp->cn_flags & NOCROSSMOUNT)) {
+                               break;
+                       }
+                       if (dp->v_mount == NULL) {      /* forced umount */
+                               error = EBADF;

                                goto bad;
                        }
                        tdp = dp;
                                goto bad;
                        }
                        tdp = dp;


@@ -1081,8 +1263,8 @@ dirloop:
 
                        vnode_put(tdp);
 
 
                        vnode_put(tdp);
 

-                       if ( (vnode_getwithref(dp)) ) {
-                               dp = NULLVP;
+                       if ((vnode_getwithref(dp))) {
+                               dp = NULLVP;

                                error = ENOENT;
                                goto bad;
                        }
                                error = ENOENT;
                                goto bad;
                        }


@@ -1098,10 +1280,10 @@ unionlookup:
        ndp->ni_vp = NULLVP;
 
        if (dp->v_type != VDIR) {
        ndp->ni_vp = NULLVP;
 
        if (dp->v_type != VDIR) {

-               error = ENOTDIR;
-               goto lookup_error;
+               error = ENOTDIR;
+               goto lookup_error;

        }
        }

-       if ( (cnp->cn_flags & DONOTAUTH) != DONOTAUTH ) {
+       if ((cnp->cn_flags & DONOTAUTH) != DONOTAUTH) {

                error = lookup_authorize_search(dp, cnp, dp_authorized, ctx);
                if (error) {
                        goto lookup_error;
                error = lookup_authorize_search(dp, cnp, dp_authorized, ctx);
                if (error) {
                        goto lookup_error;


@@ -1113,8 +1295,8 @@ unionlookup:
         * will be doing a batched operation.  Return an iocount on dvp.
         */
 #if NAMEDRSRCFORK
         * will be doing a batched operation.  Return an iocount on dvp.
         */
 #if NAMEDRSRCFORK

-       if ((cnp->cn_flags & ISLASTCN) && namei_compound_available(dp, ndp) && !(cnp->cn_flags & CN_WANTSRSRCFORK)) { 
-#else 
+       if ((cnp->cn_flags & ISLASTCN) && namei_compound_available(dp, ndp) && !(cnp->cn_flags & CN_WANTSRSRCFORK)) {
+#else

        if ((cnp->cn_flags & ISLASTCN) && namei_compound_available(dp, ndp)) {
 #endif /* NAMEDRSRCFORK */
                ndp->ni_flag |= NAMEI_UNFINISHED;
        if ((cnp->cn_flags & ISLASTCN) && namei_compound_available(dp, ndp)) {
 #endif /* NAMEDRSRCFORK */
                ndp->ni_flag |= NAMEI_UNFINISHED;


@@ -1122,10 +1304,10 @@ unionlookup:
                return 0;
        }
 
                return 0;
        }
 

-        nc_generation = dp->v_nc_generation;
+       nc_generation = dp->v_nc_generation;

 
        /*
 
        /*

-        * Note: 
+        * Note:

         * Filesystems that support hardlinks may want to call vnode_update_identity
         * if the lookup operation below will modify the in-core vnode to belong to a new point
         * in the namespace.  VFS cannot infer whether or not the look up operation makes the vnode
         * Filesystems that support hardlinks may want to call vnode_update_identity
         * if the lookup operation below will modify the in-core vnode to belong to a new point
         * in the namespace.  VFS cannot infer whether or not the look up operation makes the vnode


@@ -1136,20 +1318,20 @@ unionlookup:
         *
         * However, even with this in place, multiple lookups may occur in between this lookup
         * and the subsequent vnop, so, at best, we could only guarantee that you would get a
         *
         * However, even with this in place, multiple lookups may occur in between this lookup
         * and the subsequent vnop, so, at best, we could only guarantee that you would get a

-        * valid path back, and not necessarily the one that you wanted. 
+        * valid path back, and not necessarily the one that you wanted.

         *
         *

-        * Example: 
+        * Example:

         * /tmp/a == /foo/b
         * /tmp/a == /foo/b

-        * 
-        * If you are now looking up /foo/b and the vnode for this link represents /tmp/a, 
-        * vnode_update_identity will fix the parentage so that you can get /foo/b back 
-        * through the v_parent chain (preventing you from getting /tmp/b back). It would 
+        *
+        * If you are now looking up /foo/b and the vnode for this link represents /tmp/a,
+        * vnode_update_identity will fix the parentage so that you can get /foo/b back
+        * through the v_parent chain (preventing you from getting /tmp/b back). It would

         * not fix whether or not you should or should not get /tmp/a vs. /foo/b.
         */
 
        error = VNOP_LOOKUP(dp, &ndp->ni_vp, cnp, ctx);
 
         * not fix whether or not you should or should not get /tmp/a vs. /foo/b.
         */
 
        error = VNOP_LOOKUP(dp, &ndp->ni_vp, cnp, ctx);
 

-       if ( error ) {
+       if (error) {

 lookup_error:
                if ((error == ENOENT) &&
                    (dp->v_mount != NULL) &&
 lookup_error:
                if ((error == ENOENT) &&
                    (dp->v_mount != NULL) &&


@@ -1158,7 +1340,7 @@ lookup_error:
                        error = lookup_traverse_union(tdp, &dp, ctx);
                        vnode_put(tdp);
                        if (error) {
                        error = lookup_traverse_union(tdp, &dp, ctx);
                        vnode_put(tdp);
                        if (error) {

-                               dp = NULLVP;
+                               dp = NULLVP;

                                goto bad;
                        }
 
                                goto bad;
                        }
 


@@ -1167,24 +1349,26 @@ lookup_error:
                        goto unionlookup;
                }
 
                        goto unionlookup;
                }
 

-               if (error != EJUSTRETURN)
+               if (error != EJUSTRETURN) {

                        goto bad;
                        goto bad;

+               }

 
 

-               if (ndp->ni_vp != NULLVP)
+               if (ndp->ni_vp != NULLVP) {

                        panic("leaf should be empty");
                        panic("leaf should be empty");

+               }

 
 #if NAMEDRSRCFORK
 
 #if NAMEDRSRCFORK

-               /* 
+               /*

                 * At this point, error should be EJUSTRETURN.
                 * At this point, error should be EJUSTRETURN.

-                * 
-                * If CN_WANTSRSRCFORK is set, that implies that the 
+                *
+                * If CN_WANTSRSRCFORK is set, that implies that the

                 * underlying filesystem could not find the "parent" of the
                 * underlying filesystem could not find the "parent" of the

-                * resource fork (the data fork), and we are doing a lookup 
+                * resource fork (the data fork), and we are doing a lookup

                 * for a CREATE event.
                 *
                 * However, this should be converted to an error, as the
                 * failure to find this parent should disallow further
                 * for a CREATE event.
                 *
                 * However, this should be converted to an error, as the
                 * failure to find this parent should disallow further

-                * progress to try and acquire a resource fork vnode. 
+                * progress to try and acquire a resource fork vnode.

                 */
                if (cnp->cn_flags & CN_WANTSRSRCFORK) {
                        error = ENOENT;
                 */
                if (cnp->cn_flags & CN_WANTSRSRCFORK) {
                        error = ENOENT;


@@ -1193,32 +1377,35 @@ lookup_error:
 #endif
 
                error = lookup_validate_creation_path(ndp);
 #endif
 
                error = lookup_validate_creation_path(ndp);

-               if (error)
+               if (error) {

                        goto bad;
                        goto bad;

+               }

                /*
                 * We return with ni_vp NULL to indicate that the entry
                 * doesn't currently exist, leaving a pointer to the
                 * referenced directory vnode in ndp->ni_dvp.
                 */
                if (cnp->cn_flags & SAVESTART) {
                /*
                 * We return with ni_vp NULL to indicate that the entry
                 * doesn't currently exist, leaving a pointer to the
                 * referenced directory vnode in ndp->ni_dvp.
                 */
                if (cnp->cn_flags & SAVESTART) {

-                       if ( (vnode_get(ndp->ni_dvp)) ) {
+                       if ((vnode_get(ndp->ni_dvp))) {

                                error = ENOENT;
                                goto bad;
                        }
                        ndp->ni_startdir = ndp->ni_dvp;
                }
                                error = ENOENT;
                                goto bad;
                        }
                        ndp->ni_startdir = ndp->ni_dvp;
                }

-               if (!wantparent)
-                       vnode_put(ndp->ni_dvp);
+               if (!wantparent) {
+                       vnode_put(ndp->ni_dvp);
+               }

 
 

-               if (kdebug_enable)
-                       kdebug_lookup(ndp->ni_dvp, cnp);
-               return (0);
+               if (kdebug_enable) {
+                       kdebug_lookup(ndp->ni_dvp, cnp);
+               }
+               return 0;

        }
 returned_from_lookup_path:
        /* We'll always have an iocount on ni_vp when this finishes. */
        error = lookup_handle_found_vnode(ndp, cnp, rdonly, vbusyflags, &keep_going, nc_generation, wantparent, atroot, ctx);
        if (error != 0) {
        }
 returned_from_lookup_path:
        /* We'll always have an iocount on ni_vp when this finishes. */
        error = lookup_handle_found_vnode(ndp, cnp, rdonly, vbusyflags, &keep_going, nc_generation, wantparent, atroot, ctx);
        if (error != 0) {

-               goto bad2; 
+               goto bad2;

        }
 
        if (keep_going) {
        }
 
        if (keep_going) {


@@ -1226,12 +1413,12 @@ returned_from_lookup_path:
 
                /* namei() will handle symlinks */
                if ((dp->v_type == VLNK) &&
 
                /* namei() will handle symlinks */
                if ((dp->v_type == VLNK) &&

-                               ((cnp->cn_flags & FOLLOW) || (ndp->ni_flag & NAMEI_TRAILINGSLASH) || *ndp->ni_next == '/')) {
-                       return 0; 
+                   ((cnp->cn_flags & FOLLOW) || (ndp->ni_flag & NAMEI_TRAILINGSLASH) || *ndp->ni_next == '/')) {
+                       return 0;

                }
 
                /*
                }
 
                /*

-                * Otherwise, there's more path to process.  
+                * Otherwise, there's more path to process.

                 * cache_lookup_path is now responsible for dropping io ref on dp
                 * when it is called again in the dirloop.  This ensures we hold
                 * a ref on dp until we complete the next round of lookup.
                 * cache_lookup_path is now responsible for dropping io ref on dp
                 * when it is called again in the dirloop.  This ensures we hold
                 * a ref on dp until we complete the next round of lookup.


@@ -1241,26 +1428,30 @@ returned_from_lookup_path:
                goto dirloop;
        }
 
                goto dirloop;
        }
 

-       return (0);
+       return 0;

 bad2:
 bad2:

-       if (ndp->ni_dvp)
+       if (ndp->ni_dvp) {

                vnode_put(ndp->ni_dvp);
                vnode_put(ndp->ni_dvp);

+       }

 
        vnode_put(ndp->ni_vp);
        ndp->ni_vp = NULLVP;
 
 
        vnode_put(ndp->ni_vp);
        ndp->ni_vp = NULLVP;
 

-       if (kdebug_enable)
-               kdebug_lookup(dp, cnp);
-       return (error);
+       if (kdebug_enable) {
+               kdebug_lookup(dp, cnp);
+       }
+       return error;

 
 bad:
 
 bad:

-       if (dp)
-               vnode_put(dp);
+       if (dp) {
+               vnode_put(dp);
+       }

        ndp->ni_vp = NULLVP;
 
        ndp->ni_vp = NULLVP;
 

-       if (kdebug_enable)
-               kdebug_lookup(dp, cnp);
-       return (error);
+       if (kdebug_enable) {
+               kdebug_lookup(dp, cnp);
+       }
+       return error;

 }
 
 /*
 }
 
 /*


@@ -1281,8 +1472,9 @@ lookup_traverse_union(vnode_t dvp, vnode_t *new_dvp, vfs_context_t ctx)
 
        if (vp && vp->v_flag & VROOT) {
                *new_dvp = vp->v_mount->mnt_vnodecovered;
 
        if (vp && vp->v_flag & VROOT) {
                *new_dvp = vp->v_mount->mnt_vnodecovered;

-               if (vnode_getwithref(*new_dvp))
+               if (vnode_getwithref(*new_dvp)) {

                        return ENOENT;
                        return ENOENT;

+               }

                return 0;
        }
 
                return 0;
        }
 


@@ -1308,17 +1500,19 @@ lookup_traverse_union(vnode_t dvp, vnode_t *new_dvp, vfs_context_t ctx)
                        goto done;
                }
                len = strlen(name);
                        goto done;
                }
                len = strlen(name);

-               if ((len + 1) > (pp - path)) {          // Enough space for this name ?
+               if ((len + 1) > (pp - path)) {          // Enough space for this name ?

                        error = ENAMETOOLONG;
                        vnode_putname(name);
                        goto done;
                }
                        error = ENAMETOOLONG;
                        vnode_putname(name);
                        goto done;
                }

-               for (np = name + len; len > 0; len--)   // Copy name backwards
+               for (np = name + len; len > 0; len--) { // Copy name backwards

                        *--pp = *--np;
                        *--pp = *--np;

+               }

                vnode_putname(name);
                vp = vp->v_parent;
                vnode_putname(name);
                vp = vp->v_parent;

-               if (vp == NULLVP || vp->v_flag & VROOT)
+               if (vp == NULLVP || vp->v_flag & VROOT) {

                        break;
                        break;

+               }

                *--pp = '/';
        }
 
                *--pp = '/';
        }
 


@@ -1326,16 +1520,18 @@ lookup_traverse_union(vnode_t dvp, vnode_t *new_dvp, vfs_context_t ctx)
        NDINIT(&nd, LOOKUP, OP_LOOKUP, USEDVP, UIO_SYSSPACE, CAST_USER_ADDR_T(pp), ctx);
        nd.ni_dvp = dvp->v_mount->mnt_vnodecovered;
        error = namei(&nd);
        NDINIT(&nd, LOOKUP, OP_LOOKUP, USEDVP, UIO_SYSSPACE, CAST_USER_ADDR_T(pp), ctx);
        nd.ni_dvp = dvp->v_mount->mnt_vnodecovered;
        error = namei(&nd);

-       if (error == 0)
+       if (error == 0) {

                *new_dvp = nd.ni_vp;
                *new_dvp = nd.ni_vp;

+       }

        nameidone(&nd);
 done:
        nameidone(&nd);
 done:

-       if (path)
+       if (path) {

                kfree(path, MAXPATHLEN);
                kfree(path, MAXPATHLEN);

+       }

        return error;
 }
 
        return error;
 }
 

-int 
+int

 lookup_validate_creation_path(struct nameidata *ndp)
 {
        struct componentname *cnp = &ndp->ni_cnd;
 lookup_validate_creation_path(struct nameidata *ndp)
 {
        struct componentname *cnp = &ndp->ni_cnd;


@@ -1350,7 +1546,7 @@ lookup_validate_creation_path(struct nameidata *ndp)
        if ((cnp->cn_flags & ISLASTCN) && (ndp->ni_flag & NAMEI_TRAILINGSLASH) && !(cnp->cn_flags & WILLBEDIR)) {
                return ENOENT;
        }
        if ((cnp->cn_flags & ISLASTCN) && (ndp->ni_flag & NAMEI_TRAILINGSLASH) && !(cnp->cn_flags & WILLBEDIR)) {
                return ENOENT;
        }

-       
+

        return 0;
 }
 
        return 0;
 }
 


@@ -1358,23 +1554,24 @@ lookup_validate_creation_path(struct nameidata *ndp)
  * Modifies only ni_vp.  Always returns with ni_vp still valid (iocount held).
  */
 static int
  * Modifies only ni_vp.  Always returns with ni_vp still valid (iocount held).
  */
 static int

-lookup_traverse_mountpoints(struct nameidata *ndp, struct componentname *cnp, vnode_t dp, 
-               int vbusyflags, vfs_context_t ctx)
+lookup_traverse_mountpoints(struct nameidata *ndp, struct componentname *cnp, vnode_t dp,
+    int vbusyflags, vfs_context_t ctx)

 {
        mount_t mp;
        vnode_t tdp;
        int error = 0;
        uint32_t depth = 0;
 {
        mount_t mp;
        vnode_t tdp;
        int error = 0;
        uint32_t depth = 0;

-       vnode_t mounted_on_dp;
+       vnode_t mounted_on_dp;

        int current_mount_generation = 0;
 #if CONFIG_TRIGGERS
        vnode_t triggered_dp = NULLVP;
        int retry_cnt = 0;
 #define MAX_TRIGGER_RETRIES 1
 #endif
        int current_mount_generation = 0;
 #if CONFIG_TRIGGERS
        vnode_t triggered_dp = NULLVP;
        int retry_cnt = 0;
 #define MAX_TRIGGER_RETRIES 1
 #endif

-       
-       if (dp->v_type != VDIR || cnp->cn_flags & NOCROSSMOUNT)
+
+       if (dp->v_type != VDIR || cnp->cn_flags & NOCROSSMOUNT) {

                return 0;
                return 0;

+       }

 
        mounted_on_dp = dp;
 #if CONFIG_TRIGGERS
 
        mounted_on_dp = dp;
 #if CONFIG_TRIGGERS


@@ -1394,7 +1591,7 @@ restart:
 
                if (ISSET(mp->mnt_lflag, MNT_LFORCE)) {
                        mount_dropcrossref(mp, dp, 0);
 
                if (ISSET(mp->mnt_lflag, MNT_LFORCE)) {
                        mount_dropcrossref(mp, dp, 0);

-                       break;  // don't traverse into a forced unmount
+                       break;  // don't traverse into a forced unmount

                }
 
 
                }
 
 


@@ -1440,22 +1637,24 @@ restart:
         */
        if (dp->v_resolve && retry_cnt < MAX_TRIGGER_RETRIES) {
                error = vnode_trigger_resolve(dp, ndp, ctx);
         */
        if (dp->v_resolve && retry_cnt < MAX_TRIGGER_RETRIES) {
                error = vnode_trigger_resolve(dp, ndp, ctx);

-               if (error)
+               if (error) {

                        goto out;
                        goto out;

-               if (dp == triggered_dp)
+               }
+               if (dp == triggered_dp) {

                        retry_cnt += 1;
                        retry_cnt += 1;

-               else
+               } else {

                        retry_cnt = 0;
                        retry_cnt = 0;

+               }

                triggered_dp = dp;
                goto restart;
        }
 #endif /* CONFIG_TRIGGERS */
 
        if (depth) {
                triggered_dp = dp;
                goto restart;
        }
 #endif /* CONFIG_TRIGGERS */
 
        if (depth) {

-               mp = mounted_on_dp->v_mountedhere;
+               mp = mounted_on_dp->v_mountedhere;

 
                if (mp) {
 
                if (mp) {

-                       mount_lock_spin(mp);
+                       mount_lock_spin(mp);

                        mp->mnt_realrootvp_vid = dp->v_id;
                        mp->mnt_realrootvp = dp;
                        mp->mnt_generation = current_mount_generation;
                        mp->mnt_realrootvp_vid = dp->v_id;
                        mp->mnt_realrootvp = dp;
                        mp->mnt_generation = current_mount_generation;


@@ -1471,13 +1670,13 @@ out:
 
 /*
  * Takes ni_vp and ni_dvp non-NULL.  Returns with *new_dp set to the location
 
 /*
  * Takes ni_vp and ni_dvp non-NULL.  Returns with *new_dp set to the location

- * at which to start a lookup with a resolved path, and all other iocounts dropped.
+ * at which to start a lookup with a resolved path and with an iocount.

  */
  */

-static int 
-lookup_handle_symlink(struct nameidata *ndp, vnode_t *new_dp, vfs_context_t ctx)
+static int
+handle_symlink_for_namei(struct nameidata *ndp, vnode_t *new_dp, vfs_context_t ctx)

 {
        int error;
 {
        int error;

-       char *cp;               /* pointer into pathname argument */
+       char *cp;               /* pointer into pathname argument */

        uio_t auio;
        union {
                union {
        uio_t auio;
        union {
                union {


@@ -1485,25 +1684,28 @@ lookup_handle_symlink(struct nameidata *ndp, vnode_t *new_dp, vfs_context_t ctx)
                        struct kern_iovec s_kiovec;
                } u_iovec;
                struct uio s_uio;
                        struct kern_iovec s_kiovec;
                } u_iovec;
                struct uio s_uio;

-               char uio_buf[ UIO_SIZEOF(1) ];
+               char uio_buf[UIO_SIZEOF(1)];

        } u_uio_buf; /* union only for aligning uio_buf correctly */
        int need_newpathbuf;
        u_int linklen;
        struct componentname *cnp = &ndp->ni_cnd;
        vnode_t dp;
        char *tmppn;
        } u_uio_buf; /* union only for aligning uio_buf correctly */
        int need_newpathbuf;
        u_int linklen;
        struct componentname *cnp = &ndp->ni_cnd;
        vnode_t dp;
        char *tmppn;

+       u_int rsrclen = (cnp->cn_flags & CN_WANTSRSRCFORK) ? sizeof(_PATH_RSRCFORKSPEC) : 0;

 
        if (ndp->ni_loopcnt++ >= MAXSYMLINKS) {
                return ELOOP;
        }
 #if CONFIG_MACF
 
        if (ndp->ni_loopcnt++ >= MAXSYMLINKS) {
                return ELOOP;
        }
 #if CONFIG_MACF

-       if ((error = mac_vnode_check_readlink(ctx, ndp->ni_vp)) != 0)
+       if ((error = mac_vnode_check_readlink(ctx, ndp->ni_vp)) != 0) {

                return error;
                return error;

+       }

 #endif /* MAC */
 #endif /* MAC */

-       if (ndp->ni_pathlen > 1 || !(cnp->cn_flags & HASBUF))
+       if (ndp->ni_pathlen > 1 || !(cnp->cn_flags & HASBUF)) {

                need_newpathbuf = 1;
                need_newpathbuf = 1;

-       else
+       } else {

                need_newpathbuf = 0;
                need_newpathbuf = 0;

+       }

 
        if (need_newpathbuf) {
                MALLOC_ZONE(cp, char *, MAXPATHLEN, M_NAMEI, M_WAITOK);
 
        if (need_newpathbuf) {
                MALLOC_ZONE(cp, char *, MAXPATHLEN, M_NAMEI, M_WAITOK);


@@ -1520,20 +1722,22 @@ lookup_handle_symlink(struct nameidata *ndp, vnode_t *new_dp, vfs_context_t ctx)
 
        error = VNOP_READLINK(ndp->ni_vp, auio, ctx);
        if (error) {
 
        error = VNOP_READLINK(ndp->ni_vp, auio, ctx);
        if (error) {

-               if (need_newpathbuf)
+               if (need_newpathbuf) {

                        FREE_ZONE(cp, MAXPATHLEN, M_NAMEI);
                        FREE_ZONE(cp, MAXPATHLEN, M_NAMEI);

+               }

                return error;
        }
 
                return error;
        }
 

-       /* 
+       /*

         * Safe to set unsigned with a [larger] signed type here
         * because 0 <= uio_resid <= MAXPATHLEN and MAXPATHLEN
         * is only 1024.
         */
        linklen = MAXPATHLEN - (u_int)uio_resid(auio);
         * Safe to set unsigned with a [larger] signed type here
         * because 0 <= uio_resid <= MAXPATHLEN and MAXPATHLEN
         * is only 1024.
         */
        linklen = MAXPATHLEN - (u_int)uio_resid(auio);

-       if (linklen + ndp->ni_pathlen > MAXPATHLEN) {
-               if (need_newpathbuf)
+       if (linklen + ndp->ni_pathlen + rsrclen > MAXPATHLEN) {
+               if (need_newpathbuf) {

                        FREE_ZONE(cp, MAXPATHLEN, M_NAMEI);
                        FREE_ZONE(cp, MAXPATHLEN, M_NAMEI);

+               }

 
                return ENAMETOOLONG;
        }
 
                return ENAMETOOLONG;
        }


@@ -1545,12 +1749,14 @@ lookup_handle_symlink(struct nameidata *ndp, vnode_t *new_dp, vfs_context_t ctx)
                cnp->cn_pnbuf = cp;
                cnp->cn_pnlen = MAXPATHLEN;
 
                cnp->cn_pnbuf = cp;
                cnp->cn_pnlen = MAXPATHLEN;
 

-               if ( (cnp->cn_flags & HASBUF) )
+               if ((cnp->cn_flags & HASBUF)) {

                        FREE_ZONE(tmppn, len, M_NAMEI);
                        FREE_ZONE(tmppn, len, M_NAMEI);

-               else
+               } else {

                        cnp->cn_flags |= HASBUF;
                        cnp->cn_flags |= HASBUF;

-       } else
+               }
+       } else {

                cnp->cn_pnbuf[linklen] = '\0';
                cnp->cn_pnbuf[linklen] = '\0';

+       }

 
        ndp->ni_pathlen += linklen;
        cnp->cn_nameptr = cnp->cn_pnbuf;
 
        ndp->ni_pathlen += linklen;
        cnp->cn_nameptr = cnp->cn_pnbuf;


@@ -1558,17 +1764,18 @@ lookup_handle_symlink(struct nameidata *ndp, vnode_t *new_dp, vfs_context_t ctx)
        /*
         * starting point for 'relative'
         * symbolic link path
        /*
         * starting point for 'relative'
         * symbolic link path

+        *
+        * If the starting point is not the root we have to return an iocounted
+        * dp to namei so we don't release the icoount here.

         */
        dp = ndp->ni_dvp;
         */
        dp = ndp->ni_dvp;

+       ndp->ni_dvp = NULLVP;

 
        /*
         * get rid of references returned via 'lookup'
         */
        vnode_put(ndp->ni_vp);
 
        /*
         * get rid of references returned via 'lookup'
         */
        vnode_put(ndp->ni_vp);

-       vnode_put(ndp->ni_dvp); /* ALWAYS have a dvp for a symlink */
-

        ndp->ni_vp = NULLVP;
        ndp->ni_vp = NULLVP;

-       ndp->ni_dvp = NULLVP;

 
        /*
         * Check if symbolic link restarts us at the root
 
        /*
         * Check if symbolic link restarts us at the root


@@ -1578,9 +1785,20 @@ lookup_handle_symlink(struct nameidata *ndp, vnode_t *new_dp, vfs_context_t ctx)
                        cnp->cn_nameptr++;
                        ndp->ni_pathlen--;
                }
                        cnp->cn_nameptr++;
                        ndp->ni_pathlen--;
                }

+               vnode_put(dp);

                if ((dp = ndp->ni_rootdir) == NULLVP) {
                        return ENOENT;
                }
                if ((dp = ndp->ni_rootdir) == NULLVP) {
                        return ENOENT;
                }

+               if (vnode_get(dp) != 0) {
+                       return ENOENT;
+               }
+       }
+
+       if (dp == NULLVP || (dp->v_lflag & VL_DEAD)) {
+               if (dp) {
+                       vnode_put(dp);
+               }
+               return ENOENT;

        }
 
        *new_dp = dp;
        }
 
        *new_dp = dp;


@@ -1595,27 +1813,28 @@ lookup_handle_symlink(struct nameidata *ndp, vnode_t *new_dp, vfs_context_t ctx)
 int
 relookup(struct vnode *dvp, struct vnode **vpp, struct componentname *cnp)
 {
 int
 relookup(struct vnode *dvp, struct vnode **vpp, struct componentname *cnp)
 {

-       struct vnode *dp = NULL;                /* the directory we are searching */
-       int wantparent;                 /* 1 => wantparent or lockparent flag */
-       int rdonly;                     /* lookup read-only flag bit */
+       struct vnode *dp = NULL;                /* the directory we are searching */
+       int wantparent;                 /* 1 => wantparent or lockparent flag */
+       int rdonly;                     /* lookup read-only flag bit */

        int error = 0;
 #ifdef NAMEI_DIAGNOSTIC
        int error = 0;
 #ifdef NAMEI_DIAGNOSTIC

-       int i, newhash;                 /* DEBUG: check name hash */
-       char *cp;                       /* DEBUG: check name ptr/len */
+       int i, newhash;                 /* DEBUG: check name hash */
+       char *cp;                       /* DEBUG: check name ptr/len */

 #endif
        vfs_context_t ctx = cnp->cn_context;;
 
        /*
         * Setup: break out flag bits into variables.
         */
 #endif
        vfs_context_t ctx = cnp->cn_context;;
 
        /*
         * Setup: break out flag bits into variables.
         */

-       wantparent = cnp->cn_flags & (LOCKPARENT|WANTPARENT);
+       wantparent = cnp->cn_flags & (LOCKPARENT | WANTPARENT);

        rdonly = cnp->cn_flags & RDONLY;
        cnp->cn_flags &= ~ISSYMLINK;
 
        rdonly = cnp->cn_flags & RDONLY;
        cnp->cn_flags &= ~ISSYMLINK;
 

-       if (cnp->cn_flags & NOCACHE)
-               cnp->cn_flags &= ~MAKEENTRY;
-       else
-               cnp->cn_flags |= MAKEENTRY;
+       if (cnp->cn_flags & NOCACHE) {
+               cnp->cn_flags &= ~MAKEENTRY;
+       } else {
+               cnp->cn_flags |= MAKEENTRY;
+       }

 
        dp = dvp;
 
 
        dp = dvp;
 


@@ -1633,25 +1852,28 @@ relookup(struct vnode *dvp, struct vnode **vpp, struct componentname *cnp)
                        error = ENOTDIR;
                        goto bad;
                }
                        error = ENOTDIR;
                        goto bad;
                }

-               if ( (vnode_get(dp)) ) {
-                       error = ENOENT;
+               if ((vnode_get(dp))) {
+                       error = ENOENT;

                        goto bad;
                }
                *vpp = dp;
 
                        goto bad;
                }
                *vpp = dp;
 

-               if (cnp->cn_flags & SAVESTART)
+               if (cnp->cn_flags & SAVESTART) {

                        panic("lookup: SAVESTART");
                        panic("lookup: SAVESTART");

-               return (0);
+               }
+               return 0;

        }
        /*
         * We now have a segment name to search for, and a directory to search.
         */
        }
        /*
         * We now have a segment name to search for, and a directory to search.
         */

-       if ( (error = VNOP_LOOKUP(dp, vpp, cnp, ctx)) ) {
-               if (error != EJUSTRETURN)
+       if ((error = VNOP_LOOKUP(dp, vpp, cnp, ctx))) {
+               if (error != EJUSTRETURN) {

                        goto bad;
                        goto bad;

+               }

 #if DIAGNOSTIC
 #if DIAGNOSTIC

-               if (*vpp != NULL)
+               if (*vpp != NULL) {

                        panic("leaf should be empty");
                        panic("leaf should be empty");

+               }

 #endif
                /*
                 * If creating and at end of pathname, then can consider
 #endif
                /*
                 * If creating and at end of pathname, then can consider


@@ -1666,7 +1888,7 @@ relookup(struct vnode *dvp, struct vnode **vpp, struct componentname *cnp)
                 * doesn't currently exist, leaving a pointer to the
                 * (possibly locked) directory inode in ndp->ni_dvp.
                 */
                 * doesn't currently exist, leaving a pointer to the
                 * (possibly locked) directory inode in ndp->ni_dvp.
                 */

-               return (0);
+               return 0;

        }
        dp = *vpp;
 
        }
        dp = *vpp;
 


@@ -1674,8 +1896,9 @@ relookup(struct vnode *dvp, struct vnode **vpp, struct componentname *cnp)
        /*
         * Check for symbolic link
         */
        /*
         * Check for symbolic link
         */

-       if (dp->v_type == VLNK && (cnp->cn_flags & FOLLOW))
-               panic ("relookup: symlink found.\n");
+       if (dp->v_type == VLNK && (cnp->cn_flags & FOLLOW)) {
+               panic("relookup: symlink found.\n");
+       }

 #endif
 
        /*
 #endif
 
        /*


@@ -1687,15 +1910,15 @@ relookup(struct vnode *dvp, struct vnode **vpp, struct componentname *cnp)
                goto bad2;
        }
        /* ASSERT(dvp == ndp->ni_startdir) */
                goto bad2;
        }
        /* ASSERT(dvp == ndp->ni_startdir) */

-       
-       return (0);
+
+       return 0;

 
 bad2:
        vnode_put(dp);
 
 bad2:
        vnode_put(dp);

-bad:   
+bad:

        *vpp = NULL;
 
        *vpp = NULL;
 

-       return (error);
+       return error;

 }
 
 /*
 }
 
 /*


@@ -1746,36 +1969,61 @@ nameidone(struct nameidata *ndp)
 #if (KDEBUG_LEVEL >= KDEBUG_LEVEL_IST)
 
 void
 #if (KDEBUG_LEVEL >= KDEBUG_LEVEL_IST)
 
 void

-kdebug_lookup_gen_events(long *dbg_parms, int dbg_namelen, void *dp, boolean_t lookup)
+kdebug_vfs_lookup(long *dbg_parms, int dbg_namelen, void *dp, uint32_t flags)

 {
        int code;
        unsigned int i;
 {
        int code;
        unsigned int i;

+       bool lookup = flags & KDBG_VFS_LOOKUP_FLAG_LOOKUP;
+       bool noprocfilt = flags & KDBG_VFS_LOOKUP_FLAG_NOPROCFILT;

 
        /*
         * In the event that we collect multiple, consecutive pathname
         * entries, we must mark the start of the path's string and the end.
         */
 
        /*
         * In the event that we collect multiple, consecutive pathname
         * entries, we must mark the start of the path's string and the end.
         */

-       if (lookup == TRUE)
+       if (lookup) {

                code = VFS_LOOKUP | DBG_FUNC_START;
                code = VFS_LOOKUP | DBG_FUNC_START;

-       else
+       } else {

                code = VFS_LOOKUP_DONE | DBG_FUNC_START;
                code = VFS_LOOKUP_DONE | DBG_FUNC_START;

+       }

 
 

-       if (dbg_namelen <= (int)(3 * sizeof(long)))
+       if (dbg_namelen <= (int)(3 * sizeof(long))) {

                code |= DBG_FUNC_END;
                code |= DBG_FUNC_END;

+       }

 
 

-       KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE, code, kdebug_vnode(dp), dbg_parms[0], dbg_parms[1], dbg_parms[2], 0);
+       if (noprocfilt) {
+               KDBG_RELEASE_NOPROCFILT(code, kdebug_vnode(dp), dbg_parms[0],
+                   dbg_parms[1], dbg_parms[2]);
+       } else {
+               KDBG_RELEASE(code, kdebug_vnode(dp), dbg_parms[0], dbg_parms[1],
+                   dbg_parms[2]);
+       }

 
        code &= ~DBG_FUNC_START;
 
 
        code &= ~DBG_FUNC_START;
 

-       for (i=3, dbg_namelen -= (3 * sizeof(long)); dbg_namelen > 0; i+=4, dbg_namelen -= (4 * sizeof(long))) {
-               if (dbg_namelen <= (int)(4 * sizeof(long)))
+       for (i = 3, dbg_namelen -= (3 * sizeof(long)); dbg_namelen > 0; i += 4, dbg_namelen -= (4 * sizeof(long))) {
+               if (dbg_namelen <= (int)(4 * sizeof(long))) {

                        code |= DBG_FUNC_END;
                        code |= DBG_FUNC_END;

+               }

 
 

-               KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE, code, dbg_parms[i], dbg_parms[i+1], dbg_parms[i+2], dbg_parms[i+3], 0);
+               if (noprocfilt) {
+                       KDBG_RELEASE_NOPROCFILT(code, dbg_parms[i], dbg_parms[i + 1],
+                           dbg_parms[i + 2], dbg_parms[i + 3]);
+               } else {
+                       KDBG_RELEASE(code, dbg_parms[i], dbg_parms[i + 1], dbg_parms[i + 2],
+                           dbg_parms[i + 3]);
+               }

        }
 }
 
        }
 }
 

-static void
+void
+kdebug_lookup_gen_events(long *dbg_parms, int dbg_namelen, void *dp,
+    bool lookup)
+{
+       kdebug_vfs_lookup(dbg_parms, dbg_namelen, dp,
+           lookup ? KDBG_VFS_LOOKUP_FLAG_LOOKUP : 0);
+}
+
+void

 kdebug_lookup(vnode_t dp, struct componentname *cnp)
 {
        int dbg_namelen;
 kdebug_lookup(vnode_t dp, struct componentname *cnp)
 {
        int dbg_namelen;


@@ -1786,26 +2034,29 @@ kdebug_lookup(vnode_t dp, struct componentname *cnp)
        dbg_namelen = (cnp->cn_nameptr - cnp->cn_pnbuf) + cnp->cn_namelen;
        dbg_nameptr = cnp->cn_nameptr + cnp->cn_namelen;
 
        dbg_namelen = (cnp->cn_nameptr - cnp->cn_pnbuf) + cnp->cn_namelen;
        dbg_nameptr = cnp->cn_nameptr + cnp->cn_namelen;
 

-       if (dbg_namelen > (int)sizeof(dbg_parms))
+       if (dbg_namelen > (int)sizeof(dbg_parms)) {

                dbg_namelen = sizeof(dbg_parms);
                dbg_namelen = sizeof(dbg_parms);

+       }

        dbg_nameptr -= dbg_namelen;
        dbg_nameptr -= dbg_namelen;

-       
+

        /* Copy the (possibly truncated) path itself */
        memcpy(dbg_parms, dbg_nameptr, dbg_namelen);
        /* Copy the (possibly truncated) path itself */
        memcpy(dbg_parms, dbg_nameptr, dbg_namelen);

-       
+

        /* Pad with '\0' or '>' */
        if (dbg_namelen < (int)sizeof(dbg_parms)) {
                memset((char *)dbg_parms + dbg_namelen,
        /* Pad with '\0' or '>' */
        if (dbg_namelen < (int)sizeof(dbg_parms)) {
                memset((char *)dbg_parms + dbg_namelen,

-                      *(cnp->cn_nameptr + cnp->cn_namelen) ? '>' : 0,
-                      sizeof(dbg_parms) - dbg_namelen);
+                   *(cnp->cn_nameptr + cnp->cn_namelen) ? '>' : 0,
+                   sizeof(dbg_parms) - dbg_namelen);

        }
        }

-       kdebug_lookup_gen_events(dbg_parms, dbg_namelen, (void *)dp, TRUE);
-}      
+       kdebug_vfs_lookup(dbg_parms, dbg_namelen, (void *)dp,
+           KDBG_VFS_LOOKUP_FLAG_LOOKUP);
+}

 
 #else /* (KDEBUG_LEVEL >= KDEBUG_LEVEL_IST) */
 
 void
 
 #else /* (KDEBUG_LEVEL >= KDEBUG_LEVEL_IST) */
 
 void

-kdebug_lookup_gen_events(long *dbg_parms __unused, int dbg_namelen __unused, void *dp __unused)
+kdebug_vfs_lookup(long *dbg_parms __unused, int dbg_namelen __unused,
+    void *dp __unused, __unused uint32_t flags)

 {
 }
 
 {
 }
 


@@ -1820,7 +2071,7 @@ vfs_getbyid(fsid_t *fsid, ino64_t ino, vnode_t *vpp, vfs_context_t ctx)
 {
        mount_t mp;
        int error;
 {
        mount_t mp;
        int error;

-       
+

        mp = mount_lookupby_volfsid(fsid->val[0], 1);
        if (mp == NULL) {
                return EINVAL;
        mp = mount_lookupby_volfsid(fsid->val[0], 1);
        if (mp == NULL) {
                return EINVAL;


@@ -1868,7 +2119,7 @@ vfs_getrealpath(const char * path, char * realpath, size_t bufsize, vfs_context_
        /* Get file system id and move str to next component. */
        id = strtoul(path, &str, 10);
        if (id == 0 || str[0] != '/') {
        /* Get file system id and move str to next component. */
        id = strtoul(path, &str, 10);
        if (id == 0 || str[0] != '/') {

-               return (EINVAL);
+               return EINVAL;

        }
        while (*str == '/') {
                str++;
        }
        while (*str == '/') {
                str++;


@@ -1877,7 +2128,7 @@ vfs_getrealpath(const char * path, char * realpath, size_t bufsize, vfs_context_
 
        mp = mount_lookupby_volfsid(id, 1);
        if (mp == NULL) {
 
        mp = mount_lookupby_volfsid(id, 1);
        if (mp == NULL) {

-               return (EINVAL);  /* unexpected failure */
+               return EINVAL;  /* unexpected failure */

        }
        /* Check for an alias to a file system root. */
        if (ch == '@' && str[1] == '\0') {
        }
        /* Check for an alias to a file system root. */
        if (ch == '@' && str[1] == '\0') {


@@ -1885,12 +2136,29 @@ vfs_getrealpath(const char * path, char * realpath, size_t bufsize, vfs_context_
                str++;
        } else {
                /* Get file id and move str to next component. */
                str++;
        } else {
                /* Get file id and move str to next component. */

-           ino = strtouq(str, &str, 10);
+               ino = strtouq(str, &str, 10);

        }
 
        /* Get the target vnode. */
        if (ino == 2) {
        }
 
        /* Get the target vnode. */
        if (ino == 2) {

-               error = VFS_ROOT(mp, &vp, ctx);
+               struct vfs_attr vfsattr;
+               int use_vfs_root = TRUE;
+
+               VFSATTR_INIT(&vfsattr);
+               VFSATTR_WANTED(&vfsattr, f_capabilities);
+               if (vfs_getattr(mp, &vfsattr, vfs_context_kernel()) == 0 &&
+                   VFSATTR_IS_SUPPORTED(&vfsattr, f_capabilities)) {
+                       if ((vfsattr.f_capabilities.capabilities[VOL_CAPABILITIES_FORMAT] & VOL_CAP_FMT_VOL_GROUPS) &&
+                           (vfsattr.f_capabilities.valid[VOL_CAPABILITIES_FORMAT] & VOL_CAP_FMT_VOL_GROUPS)) {
+                               use_vfs_root = FALSE;
+                       }
+               }
+
+               if (use_vfs_root) {
+                       error = VFS_ROOT(mp, &vp, ctx);
+               } else {
+                       error = VFS_VGET(mp, ino, &vp, ctx);
+               }

        } else {
                error = VFS_VGET(mp, ino, &vp, ctx);
        }
        } else {
                error = VFS_VGET(mp, ino, &vp, ctx);
        }


@@ -1906,12 +2174,12 @@ vfs_getrealpath(const char * path, char * realpath, size_t bufsize, vfs_context_
 
        if (error == 0 && *str != '\0') {
                int attempt = strlcat(realpath, str, MAXPATHLEN);
 
        if (error == 0 && *str != '\0') {
                int attempt = strlcat(realpath, str, MAXPATHLEN);

-               if (attempt > MAXPATHLEN){
+               if (attempt > MAXPATHLEN) {

                        error = ENAMETOOLONG;
                }
        }
 out:
                        error = ENAMETOOLONG;
                }
        }
 out:

-       return (error);
+       return error;

 }
 #endif
 
 }
 #endif
 


@@ -1922,7 +2190,7 @@ lookup_compound_vnop_post_hook(int error, vnode_t dvp, vnode_t vp, struct nameid
                panic("NULL vp with error == 0.\n");
        }
 
                panic("NULL vp with error == 0.\n");
        }
 

-       /* 
+       /*

         * We don't want to do any of this if we didn't use the compound vnop
         * to perform the lookup... i.e. if we're allowing and using the legacy pattern,
         * where we did a full lookup.
         * We don't want to do any of this if we didn't use the compound vnop
         * to perform the lookup... i.e. if we're allowing and using the legacy pattern,
         * where we did a full lookup.


@@ -1931,7 +2199,7 @@ lookup_compound_vnop_post_hook(int error, vnode_t dvp, vnode_t vp, struct nameid
                return;
        }
 
                return;
        }
 

-       /* 
+       /*

         * If we're going to continue the lookup, we'll handle
         * all lookup-related updates at that time.
         */
         * If we're going to continue the lookup, we'll handle
         * all lookup-related updates at that time.
         */


@@ -1944,29 +2212,30 @@ lookup_compound_vnop_post_hook(int error, vnode_t dvp, vnode_t vp, struct nameid
         * neither would happen in the non-compound-vnop case.
         */
        if ((vp != NULLVP) && !did_create) {
         * neither would happen in the non-compound-vnop case.
         */
        if ((vp != NULLVP) && !did_create) {

-               /* 
-                * If MAKEENTRY isn't set, and we've done a successful compound VNOP, 
+               /*
+                * If MAKEENTRY isn't set, and we've done a successful compound VNOP,

                 * then we certainly don't want to update cache or identity.
                 */
                if ((error != 0) || (ndp->ni_cnd.cn_flags & MAKEENTRY)) {
                        lookup_consider_update_cache(dvp, vp, &ndp->ni_cnd, ndp->ni_ncgeneration);
                }
                 * then we certainly don't want to update cache or identity.
                 */
                if ((error != 0) || (ndp->ni_cnd.cn_flags & MAKEENTRY)) {
                        lookup_consider_update_cache(dvp, vp, &ndp->ni_cnd, ndp->ni_ncgeneration);
                }

-               if (ndp->ni_cnd.cn_flags & AUDITVNPATH1)
+               if (ndp->ni_cnd.cn_flags & AUDITVNPATH1) {

                        AUDIT_ARG(vnpath, vp, ARG_VNODE1);
                        AUDIT_ARG(vnpath, vp, ARG_VNODE1);

-               else if (ndp->ni_cnd.cn_flags & AUDITVNPATH2)
+               } else if (ndp->ni_cnd.cn_flags & AUDITVNPATH2) {

                        AUDIT_ARG(vnpath, vp, ARG_VNODE2);
                        AUDIT_ARG(vnpath, vp, ARG_VNODE2);

+               }

        }
 
        }
 

-       /* 
-        * If you created (whether you opened or not), cut a lookup tracepoint 
+       /*
+        * If you created (whether you opened or not), cut a lookup tracepoint

         * for the parent dir (as would happen without a compound vnop).  Note: we may need
         * a vnode despite failure in this case!
         *
         * If you did not create:
         * for the parent dir (as would happen without a compound vnop).  Note: we may need
         * a vnode despite failure in this case!
         *
         * If you did not create:

-        *      Found child (succeeded or not): cut a tracepoint for the child.  
-        *      Did not find child: cut a tracepoint with the parent.
+        *      Found child (succeeded or not): cut a tracepoint for the child.
+        *      Did not find child: cut a tracepoint with the parent.

         */
        if (kdebug_enable) {
         */
        if (kdebug_enable) {

-               kdebug_lookup(vp ? vp : dvp, &ndp->ni_cnd); 
+               kdebug_lookup(vp ? vp : dvp, &ndp->ni_cnd);

        }
 }
        }
 }