/*
- * Copyright (c) 2000-2010 Apple Inc. All rights reserved.
+ * 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
* unlawful or unlicensed copies of an Apple operating system, or to
* circumvent, violate, or enable the circumvention or violation of, any
* terms of an Apple operating system software license agreement.
- *
+ *
* Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this file.
- *
+ *
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* 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 */
#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 <security/audit/audit.h>
-
+#include <sys/dtrace.h> /* to get the prototype for strstr() in sys/dtrace_glue.h */
#if CONFIG_MACF
#include <security/mac_framework.h>
#endif
+#include <sys/paths.h>
+
#if NAMEDRSRCFORK
#include <sys/xattr.h>
#endif
#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
-boolean_t lookup_continue_ok(struct nameidata *ndp);
-int lookup_traverse_mountpoints(struct nameidata *ndp, struct componentname *cnp, vnode_t dp, int vbusyflags, vfs_context_t ctx);
-int lookup_handle_symlink(struct nameidata *ndp, vnode_t *new_dp, vfs_context_t ctx);
-int lookup_authorize_search(vnode_t dp, struct componentname *cnp, int dp_authorized_in_cache, vfs_context_t ctx);
-void lookup_consider_update_cache(vnode_t dvp, vnode_t vp, struct componentname *cnp, int nc_generation);
-int lookup_handle_rsrc_fork(vnode_t dp, struct nameidata *ndp, struct componentname *cnp, int wantparent, vfs_context_t ctx);
-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);
-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 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);
+
+#if NAMEDRSRCFORK
+static int lookup_handle_rsrc_fork(vnode_t dp, struct nameidata *ndp, struct componentname *cnp, int wantparent, vfs_context_t ctx);
+#endif
+
+
/*
* Convert a pathname into a pointer to a locked inode.
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 *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;
uthread_t ut = (struct uthread *)get_bsdthread_info(current_thread());
#endif
+#if CONFIG_VOLFS
+ int volfs_restarts = 0;
+#endif
+ size_t bytes_copied = 0;
+ bool take_proc_lock = !(ndp->ni_flag & NAMEI_NOPROCLOCK);
+ bool proc_lock_taken = false;
+
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
/*
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;
+ }
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);
}
return 0;
-
}
vnode_recycled:
}
#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,
- cnp->cn_pnlen, (size_t *)&ndp->ni_pathlen);
+ cnp->cn_pnlen, &bytes_copied);
} else {
error = copystr(CAST_DOWN(void *, ndp->ni_dirp), cnp->cn_pnbuf,
- cnp->cn_pnlen, (size_t *)&ndp->ni_pathlen);
+ cnp->cn_pnlen, &bytes_copied);
}
if (error == ENAMETOOLONG && !(cnp->cn_flags & HASBUF)) {
MALLOC_ZONE(cnp->cn_pnbuf, caddr_t, MAXPATHLEN, M_NAMEI, M_WAITOK);
cnp->cn_flags |= HASBUF;
cnp->cn_pnlen = MAXPATHLEN;
-
+ bytes_copied = 0;
+
goto retry_copy;
}
- if (error)
- goto error_out;
+ if (error) {
+ goto error_out;
+ }
+ ndp->ni_pathlen = bytes_copied;
+ bytes_copied = 0;
+
+ /*
+ * Since the name cache may contain positive entries of
+ * the incorrect case, force lookup() to bypass the cache
+ * and call directly into the filesystem for each path
+ * 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)) {
+ cnp->cn_flags |= CN_SKIPNAMECACHE;
+ }
#if CONFIG_VOLFS
- /*
+ /*
* Check for legacy volfs style pathnames.
*
* For compatibility reasons we currently allow these paths,
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) {
- /*
+ /*
* 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);
- if (realpath_err == ENOSPC || realpath_err == ENAMETOOLONG){
+ if (realpath_err == ENOSPC || realpath_err == ENAMETOOLONG) {
error = ENAMETOOLONG;
goto error_out;
}
#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 */
/*
/*
* determine the starting point for the translation.
+ *
+ * We hold the proc_dirs lock across the lookup so that the
+ * process rootdir and cwd are stable (i.e. the usecounts
+ * on them are mainatained for the duration of the lookup)
*/
- if ((ndp->ni_rootdir = fdp->fd_rdir) == NULLVP) {
- if ( !(fdp->fd_flags & FD_CHROOT))
- ndp->ni_rootdir = rootvnode;
+ if (take_proc_lock) {
+ assert(proc_lock_taken == false);
+ proc_dirs_lock_shared(p);
+ proc_lock_taken = true;
+ }
+ 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)) {
+ printf("rootvnode is not set\n");
+ } else {
+ /* This should be a panic */
+ printf("fdp->fd_rdir is not set\n");
+ }
+ error = ENOENT;
+ goto error_out;
}
+
cnp->cn_nameptr = cnp->cn_pnbuf;
ndp->ni_usedvp = NULLVP;
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) {
- dp = ndp->ni_dvp;
+ dp = ndp->ni_dvp;
ndp->ni_usedvp = dp;
- } else
- dp = vfs_context_cwd(ctx);
+ } else {
+ dp = vfs_context_cwd(ctx);
+ }
if (dp == NULLVP || (dp->v_lflag & VL_DEAD)) {
- error = ENOENT;
+ dp = NULLVP;
+ error = ENOENT;
goto error_out;
}
+
ndp->ni_dvp = NULLVP;
ndp->ni_vp = NULLVP;
for (;;) {
+#if CONFIG_MACF
+ /*
+ * Give MACF policies a chance to reject the lookup
+ * before performing any filesystem operations.
+ * This hook is called before resolving the path and
+ * again each time a symlink is encountered.
+ * NB: policies receive path information as supplied
+ * by the caller and thus cannot be trusted.
+ */
+ error = mac_vnode_check_lookup_preflight(ctx, dp, cnp->cn_nameptr, cnp->cn_namelen);
+ if (error) {
+ goto error_out;
+ }
+#endif
ndp->ni_startdir = dp;
+ dp = NULLVP;
- if ( (error = lookup(ndp)) ) {
+ if ((error = lookup(ndp))) {
goto error_out;
}
+
/*
* Check for symbolic link
*/
if ((cnp->cn_flags & ISSYMLINK) == 0) {
- return (0);
+ if (proc_lock_taken) {
+ proc_dirs_unlock_shared(p);
+ proc_lock_taken = false;
+ }
+ return 0;
}
continue_symlink:
* 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 (proc_lock_taken) {
+ proc_dirs_unlock_shared(p);
+ proc_lock_taken = false;
+ }
+ if ((cnp->cn_flags & HASBUF)) {
cnp->cn_flags &= ~HASBUF;
FREE_ZONE(cnp->cn_pnbuf, cnp->cn_pnlen, M_NAMEI);
}
cnp->cn_pnbuf = NULL;
ndp->ni_vp = NULLVP;
ndp->ni_dvp = NULLVP;
- if (error == ERECYCLE){
- /* vnode was recycled underneath us. re-drive lookup to start at
- the beginning again, since recycling invalidated last lookup*/
+
+#if CONFIG_VOLFS
+ /*
+ * 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
+ * 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
+ * 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.
+ *
+ * Do this dance a maximum of MAX_VOLFS_RESTARTS times.
+ */
+ if ((error == ENOENT) && (ndp->ni_cnd.cn_flags & CN_VOLFSPATH)) {
+ if (volfs_restarts < MAX_VOLFS_RESTARTS) {
+ volfs_restarts++;
+ goto vnode_recycled;
+ }
+ }
+#endif
+
+ 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;
}
- return (error);
+ return error;
}
-int
+int
namei_compound_available(vnode_t dp, struct nameidata *ndp)
{
if ((ndp->ni_flag & NAMEI_COMPOUNDOPEN) != 0) {
return 0;
}
-int
+
+static int
lookup_authorize_search(vnode_t dp, struct componentname *cnp, int dp_authorized_in_cache, vfs_context_t ctx)
{
+#if !CONFIG_MACF
+#pragma unused(cnp)
+#endif
+
int error;
if (!dp_authorized_in_cache) {
error = vnode_authorize(dp, NULL, KAUTH_VNODE_SEARCH, ctx);
- if (error)
+ if (error) {
return error;
+ }
}
#if CONFIG_MACF
error = mac_vnode_check_lookup(ctx, dp, cnp);
- if (error)
+ if (error) {
return error;
+ }
#endif /* CONFIG_MACF */
return 0;
}
-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 update_flags = 0;
if (isdot_or_dotdot == 0) {
- if (vp->v_name == NULL)
+ if (vp->v_name == NULL) {
update_flags |= VNODE_UPDATE_NAME;
- if (dvp != NULLVP && vp->v_parent == NULLVP)
+ }
+ if (dvp != NULLVP && vp->v_parent == NULLVP) {
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);
+ }
}
}
- 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
* 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);
+ }
}
-
}
#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).
*/
-int
+static int
lookup_handle_rsrc_fork(vnode_t dp, struct nameidata *ndp, struct componentname *cnp, int wantparent, vfs_context_t ctx)
{
vnode_t svp = NULLVP;
enum nsoperation nsop;
+ int nsflags;
int error;
if (dp->v_type != VREG) {
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;
+ }
+ 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;
+ if (cnp->cn_flags & CN_RAW_ENCRYPTED) {
+ nsflags |= NS_GETRAWENCRYPTED;
+ }
+
/* Ask the file system for the resource fork. */
- error = vnode_getnamedstream(dp, &svp, XATTR_RESOURCEFORK_NAME, nsop, 0, ctx);
+ error = vnode_getnamedstream(dp, &svp, XATTR_RESOURCEFORK_NAME, nsop, nsflags, ctx);
/* 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;
}
/* The "parent" of the stream is the file. */
if (wantparent) {
if (ndp->ni_dvp) {
-#ifndef __LP64__
- if (ndp->ni_cnd.cn_flags & FSNODELOCKHELD) {
- ndp->ni_cnd.cn_flags &= ~FSNODELOCKHELD;
- unlock_fsnode(ndp->ni_dvp, NULL);
- }
-#endif /* __LP64__ */
vnode_put(ndp->ni_dvp);
}
ndp->ni_dvp = dp;
/* 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;
/*
* 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
- * 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).
*/
-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;
goto nextname;
}
-#if CONFIG_TRIGGERS
- if (dp->v_resolve) {
- error = vnode_trigger_resolve(dp, ndp, ctx);
- if (error) {
- goto out;
- }
- }
-#endif /* CONFIG_TRIGGERS */
-
/*
* Take into account any additional components consumed by
* the underlying filesystem.
#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;
+ }
}
#endif
((cnp->cn_flags & FOLLOW) || (ndp->ni_flag & NAMEI_TRAILINGSLASH) || *ndp->ni_next == '/')) {
cnp->cn_flags |= ISSYMLINK;
*keep_going = 1;
- return (0);
+ return 0;
}
/*
goto out;
}
ndp->ni_flag &= ~(NAMEI_TRAILINGSLASH);
- }
-
+ }
+
+#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
+ */
+ if (vnode_isshadow(dp)) {
+ error = ENOENT;
+ goto out;
+ }
+#endif
+
nextname:
/*
* 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;
*keep_going = 1;
return 0;
}
-
+
/*
* Disallow directory write attempts on read-only file systems.
*/
error = EROFS;
goto out;
}
-
+
/* 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'
*/
- if ( (vnode_get(ndp->ni_dvp)) ) {
- error = ENOENT;
+ if ((vnode_get(ndp->ni_dvp))) {
+ error = ENOENT;
goto out;
}
ndp->ni_startdir = ndp->ni_dvp;
ndp->ni_dvp = NULLVP;
}
- if (cnp->cn_flags & AUDITVNPATH1)
+ if (cnp->cn_flags & AUDITVNPATH1) {
AUDIT_ARG(vnpath, dp, ARG_VNODE1);
- else if (cnp->cn_flags & AUDITVNPATH2)
+ } else if (cnp->cn_flags & AUDITVNPATH2) {
AUDIT_ARG(vnpath, dp, ARG_VNODE2);
+ }
#if NAMEDRSRCFORK
/*
*/
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;
+ }
dp = ndp->ni_vp;
}
#endif
- if (kdebug_enable)
- kdebug_lookup(dp, cnp);
+ if (kdebug_enable) {
+ kdebug_lookup(ndp->ni_vp, cnp);
+ }
return 0;
emptyname:
error = lookup_handle_emptyname(ndp, cnp, wantparent);
- if (error != 0)
+ if (error != 0) {
goto out;
+ }
return 0;
out:
return error;
-
}
/*
* Comes in iocount on ni_vp. May overwrite ni_dvp, but doesn't interpret incoming value.
*/
-int
+static int
lookup_handle_emptyname(struct nameidata *ndp, struct componentname *cnp, int wantparent)
{
vnode_t dp;
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'
*/
- if ( (vnode_get(dp)) ) {
- error = ENOENT;
+ if ((vnode_get(dp))) {
+ error = ENOENT;
goto out;
}
ndp->ni_dvp = 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);
- else if (cnp->cn_flags & AUDITVNPATH2)
+ } else if (cnp->cn_flags & AUDITVNPATH2) {
AUDIT_ARG(vnpath, dp, ARG_VNODE2);
- if (cnp->cn_flags & SAVESTART)
+ }
+ if (cnp->cn_flags & SAVESTART) {
panic("lookup: SAVESTART");
+ }
return 0;
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 ".".
- *
+ *
* Overall outline of lookup:
*
* dirloop:
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;
/*
* Setup: break out flag bits into variables.
*/
- if (cnp->cn_flags & (NOCACHE | DOWHITEOUT)) {
- if ((cnp->cn_flags & NOCACHE) || (cnp->cn_nameiop == DELETE))
- docache = 0;
+ if (cnp->cn_flags & NOCACHE) {
+ docache = 0;
}
wantparent = cnp->cn_flags & (LOCKPARENT | WANTPARENT);
rdonly = cnp->cn_flags & RDONLY;
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') {
- if ( (vnode_getwithref(dp)) ) {
+ if ((vnode_getwithref(dp))) {
dp = NULLVP;
- error = ENOENT;
+ error = ENOENT;
goto bad;
}
ndp->ni_vp = dp;
return 0;
}
-dirloop:
+dirloop:
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)) {
- 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) {
- /*
+ /*
* 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
* 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;
}
/*
* 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) &&
+ dp != ndp->ni_rootdir) {
+ int sdir_error;
+ int is_subdir = FALSE;
+
+ sdir_error = vnode_issubdir(dp, ndp->ni_rootdir,
+ &is_subdir, vfs_context_kernel());
+
+ /*
+ * If we couldn't determine if dp is a subdirectory of
+ * ndp->ni_rootdir (sdir_error != 0), we let the request
+ * proceed.
+ */
+ if (!sdir_error && !is_subdir) {
+ vnode_put(dp);
+ dp = ndp->ni_rootdir;
+ /*
+ * There's a ref on the process's root directory
+ * but we can't use vnode_getwithref here as
+ * there is nothing preventing that ref being
+ * released by another thread.
+ */
+ if (vnode_get(dp)) {
+ error = ENOENT;
+ goto bad;
+ }
+ }
+ }
+
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
* 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;
}
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;
dp = tdp->v_mount->mnt_vnodecovered;
- vnode_put(tdp);
-
- if ( (vnode_getwithref(dp)) ) {
- dp = NULLVP;
+ if ((vnode_getwithref(dp))) {
+ vnode_put(tdp);
+ dp = NULLVP;
error = ENOENT;
goto bad;
}
+
+ vnode_put(tdp);
+
ndp->ni_dvp = dp;
dp_authorized = 0;
}
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;
*/
#if NAMEDRSRCFORK
if ((cnp->cn_flags & ISLASTCN) && namei_compound_available(dp, ndp) && !(cnp->cn_flags & CN_WANTSRSRCFORK)) {
-#else
+#else
if ((cnp->cn_flags & ISLASTCN) && namei_compound_available(dp, ndp)) {
#endif /* NAMEDRSRCFORK */
ndp->ni_flag |= NAMEI_UNFINISHED;
return 0;
}
- nc_generation = dp->v_nc_generation;
+ nc_generation = dp->v_nc_generation;
- error = VNOP_LOOKUP(dp, &ndp->ni_vp, cnp, ctx);
+ /*
+ * 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
+ * name change or change parents. Without this, the lookup may make update
+ * filesystem-specific in-core metadata but fail to update the v_parent or v_name
+ * fields in the vnode. If VFS were to do this, it would be necessary to call
+ * vnode_update_identity on every lookup operation -- expensive!
+ *
+ * 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.
+ *
+ * Example:
+ * /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
+ * 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_flag & VROOT) && (dp->v_mount != NULL) &&
+ (dp->v_mount != NULL) &&
(dp->v_mount->mnt_flag & MNT_UNION)) {
-#ifndef __LP64__
- if ((cnp->cn_flags & FSNODELOCKHELD)) {
- cnp->cn_flags &= ~FSNODELOCKHELD;
- unlock_fsnode(dp, NULL);
- }
-#endif /* __LP64__ */
tdp = dp;
- dp = tdp->v_mount->mnt_vnodecovered;
-
+ error = lookup_traverse_union(tdp, &dp, ctx);
vnode_put(tdp);
-
- if ( (vnode_getwithref(dp)) ) {
- dp = NULLVP;
- error = ENOENT;
+ if (error) {
+ dp = NULLVP;
goto bad;
}
+
ndp->ni_dvp = dp;
dp_authorized = 0;
goto unionlookup;
}
- if (error != EJUSTRETURN)
+ if (error != EJUSTRETURN) {
goto bad;
+ }
- if (ndp->ni_vp != NULLVP)
+ if (ndp->ni_vp != NULLVP) {
panic("leaf should be empty");
+ }
+
+#if NAMEDRSRCFORK
+ /*
+ * At this point, error should be EJUSTRETURN.
+ *
+ * If CN_WANTSRSRCFORK is set, that implies that the
+ * underlying filesystem could not find the "parent" of the
+ * 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
+ * progress to try and acquire a resource fork vnode.
+ */
+ if (cnp->cn_flags & CN_WANTSRSRCFORK) {
+ error = ENOENT;
+ goto bad;
+ }
+#endif
error = lookup_validate_creation_path(ndp);
- if (error)
+ if (error) {
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) {
- if ( (vnode_get(ndp->ni_dvp)) ) {
+ if ((vnode_get(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) {
- goto bad2;
+ goto bad2;
}
if (keep_going) {
/* 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.
goto dirloop;
}
- return (0);
+ return 0;
bad2:
-#ifndef __LP64__
- if ((cnp->cn_flags & FSNODELOCKHELD)) {
- cnp->cn_flags &= ~FSNODELOCKHELD;
- unlock_fsnode(ndp->ni_dvp, NULL);
- }
-#endif /* __LP64__ */
- if (ndp->ni_dvp)
+ if (ndp->ni_dvp) {
vnode_put(ndp->ni_dvp);
+ }
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:
-#ifndef __LP64__
- if ((cnp->cn_flags & FSNODELOCKHELD)) {
- cnp->cn_flags &= ~FSNODELOCKHELD;
- unlock_fsnode(ndp->ni_dvp, NULL);
- }
-#endif /* __LP64__ */
- if (dp)
- vnode_put(dp);
+ if (dp) {
+ vnode_put(dp);
+ }
ndp->ni_vp = NULLVP;
- if (kdebug_enable)
- kdebug_lookup(dp, cnp);
- return (error);
+ if (kdebug_enable) {
+ kdebug_lookup(dp, cnp);
+ }
+ return error;
+}
+
+/*
+ * Given a vnode in a union mount, traverse to the equivalent
+ * vnode in the underlying mount.
+ */
+int
+lookup_traverse_union(vnode_t dvp, vnode_t *new_dvp, vfs_context_t ctx)
+{
+ char *path = NULL, *pp;
+ const char *name, *np;
+ int len;
+ int error = 0;
+ struct nameidata nd;
+ vnode_t vp = dvp;
+
+ *new_dvp = NULL;
+
+ if (vp && vp->v_flag & VROOT) {
+ *new_dvp = vp->v_mount->mnt_vnodecovered;
+ if (vnode_getwithref(*new_dvp)) {
+ return ENOENT;
+ }
+ return 0;
+ }
+
+ path = (char *) kalloc(MAXPATHLEN);
+ if (path == NULL) {
+ error = ENOMEM;
+ goto done;
+ }
+
+ /*
+ * Walk back up to the mountpoint following the
+ * v_parent chain and build a slash-separated path.
+ * Then lookup that path starting with the covered vnode.
+ */
+ pp = path + (MAXPATHLEN - 1);
+ *pp = '\0';
+
+ while (1) {
+ name = vnode_getname(vp);
+ if (name == NULL) {
+ printf("lookup_traverse_union: null parent name: .%s\n", pp);
+ error = ENOENT;
+ goto done;
+ }
+ len = strlen(name);
+ if ((len + 1) > (pp - path)) { // Enough space for this name ?
+ error = ENAMETOOLONG;
+ vnode_putname(name);
+ goto done;
+ }
+ for (np = name + len; len > 0; len--) { // Copy name backwards
+ *--pp = *--np;
+ }
+ vnode_putname(name);
+ vp = vp->v_parent;
+ if (vp == NULLVP || vp->v_flag & VROOT) {
+ break;
+ }
+ *--pp = '/';
+ }
+
+ /* Evaluate the path in the underlying mount */
+ 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) {
+ *new_dvp = nd.ni_vp;
+ }
+ nameidone(&nd);
+done:
+ if (path) {
+ kfree(path, MAXPATHLEN);
+ }
+ return error;
}
-int
+int
lookup_validate_creation_path(struct nameidata *ndp)
{
struct componentname *cnp = &ndp->ni_cnd;
if ((cnp->cn_flags & ISLASTCN) && (ndp->ni_flag & NAMEI_TRAILINGSLASH) && !(cnp->cn_flags & WILLBEDIR)) {
return ENOENT;
}
-
+
return 0;
}
/*
* Modifies only ni_vp. Always returns with ni_vp still valid (iocount held).
*/
-int
-lookup_traverse_mountpoints(struct nameidata *ndp, struct componentname *cnp, vnode_t dp,
- int vbusyflags, vfs_context_t ctx)
+static int
+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;
- uthread_t uth;
uint32_t depth = 0;
- int dont_cache_mp = 0;
- vnode_t mounted_on_dp;
+ vnode_t mounted_on_dp;
int current_mount_generation = 0;
-
- mounted_on_dp = dp;
- current_mount_generation = mount_generation;
-
- while ((dp->v_type == VDIR) && dp->v_mountedhere &&
- ((cnp->cn_flags & NOCROSSMOUNT) == 0)) {
#if CONFIG_TRIGGERS
- /*
- * For a trigger vnode, call its resolver when crossing its mount (if requested)
- */
- if (dp->v_resolve) {
- (void) vnode_trigger_resolve(dp, ndp, ctx);
- }
+ vnode_t triggered_dp = NULLVP;
+ int retry_cnt = 0;
+#define MAX_TRIGGER_RETRIES 1
#endif
- vnode_lock(dp);
- if ((dp->v_type == VDIR) && (mp = dp->v_mountedhere)) {
+ if (dp->v_type != VDIR || cnp->cn_flags & NOCROSSMOUNT) {
+ return 0;
+ }
+
+ mounted_on_dp = dp;
+#if CONFIG_TRIGGERS
+restart:
+#endif
+ current_mount_generation = mount_generation;
+ while (dp->v_mountedhere) {
+ vnode_lock_spin(dp);
+ if ((mp = dp->v_mountedhere)) {
mp->mnt_crossref++;
vnode_unlock(dp);
+ } else {
+ vnode_unlock(dp);
+ break;
+ }
+ if (ISSET(mp->mnt_lflag, MNT_LFORCE)) {
+ mount_dropcrossref(mp, dp, 0);
+ break; // don't traverse into a forced unmount
+ }
- if (vfs_busy(mp, vbusyflags)) {
- mount_dropcrossref(mp, dp, 0);
- if (vbusyflags == LK_NOWAIT) {
- error = ENOENT;
- goto out;
- }
- continue;
+ if (vfs_busy(mp, vbusyflags)) {
+ mount_dropcrossref(mp, dp, 0);
+ if (vbusyflags == LK_NOWAIT) {
+ error = ENOENT;
+ goto out;
}
+ continue;
+ }
- /*
- * XXX - if this is the last component of the
- * pathname, and it's either not a lookup operation
- * or the NOTRIGGER flag is set for the operation,
- * set a uthread flag to let VFS_ROOT() for autofs
- * know it shouldn't trigger a mount.
- */
- uth = (struct uthread *)get_bsdthread_info(current_thread());
- if ((cnp->cn_flags & ISLASTCN) &&
- (cnp->cn_nameiop != LOOKUP ||
- (cnp->cn_flags & NOTRIGGER))) {
- uth->uu_notrigger = 1;
- dont_cache_mp = 1;
- }
-
- error = VFS_ROOT(mp, &tdp, ctx);
- /* XXX - clear the uthread flag */
- uth->uu_notrigger = 0;
+ error = VFS_ROOT(mp, &tdp, ctx);
- mount_dropcrossref(mp, dp, 0);
- vfs_unbusy(mp);
+ mount_dropcrossref(mp, dp, 0);
+ vfs_unbusy(mp);
- if (error) {
- goto out;
- }
+ if (error) {
+ goto out;
+ }
- vnode_put(dp);
- ndp->ni_vp = dp = tdp;
- depth++;
+ vnode_put(dp);
+ ndp->ni_vp = dp = tdp;
+ if (dp->v_type != VDIR) {
+#if DEVELOPMENT || DEBUG
+ panic("%s : Root of filesystem not a directory\n",
+ __FUNCTION__);
+#else
+ break;
+#endif
+ }
+ depth++;
+ }
#if CONFIG_TRIGGERS
- /*
- * Check if root dir is a trigger vnode
- */
- if (dp->v_resolve) {
- error = vnode_trigger_resolve(dp, ndp, ctx);
- if (error) {
- goto out;
- }
- }
-#endif
-
- } else {
- vnode_unlock(dp);
- break;
+ /*
+ * The triggered_dp check here is required but is susceptible to a
+ * (unlikely) race in which trigger mount is done from here and is
+ * unmounted before we get past vfs_busy above. We retry to deal with
+ * that case but it has the side effect of unwanted retries for
+ * "special" processes which don't want to trigger mounts.
+ */
+ if (dp->v_resolve && retry_cnt < MAX_TRIGGER_RETRIES) {
+ error = vnode_trigger_resolve(dp, ndp, ctx);
+ if (error) {
+ goto out;
+ }
+ if (dp == triggered_dp) {
+ retry_cnt += 1;
+ } else {
+ retry_cnt = 0;
}
+ triggered_dp = dp;
+ goto restart;
}
+#endif /* CONFIG_TRIGGERS */
- if (depth && !dont_cache_mp) {
- mp = mounted_on_dp->v_mountedhere;
+ if (depth) {
+ mp = mounted_on_dp->v_mountedhere;
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;
* 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.
*/
-int
+static int
lookup_handle_symlink(struct nameidata *ndp, vnode_t *new_dp, vfs_context_t ctx)
{
int error;
- char *cp; /* pointer into pathname argument */
+ char *cp; /* pointer into pathname argument */
uio_t auio;
- char uio_buf[ UIO_SIZEOF(1) ];
+ union {
+ union {
+ struct user_iovec s_uiovec;
+ struct kern_iovec s_kiovec;
+ } u_iovec;
+ struct uio s_uio;
+ 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;
-
-#ifndef __LP64__
- if ((cnp->cn_flags & FSNODELOCKHELD)) {
- cnp->cn_flags &= ~FSNODELOCKHELD;
- unlock_fsnode(ndp->ni_dvp, NULL);
- }
-#endif /* __LP64__ */
+ u_int rsrclen = (cnp->cn_flags & CN_WANTSRSRCFORK) ? sizeof(_PATH_RSRCFORKSPEC) : 0;
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;
+ }
#endif /* MAC */
- if (ndp->ni_pathlen > 1 || !(cnp->cn_flags & HASBUF))
+ if (ndp->ni_pathlen > 1 || !(cnp->cn_flags & HASBUF)) {
need_newpathbuf = 1;
- else
+ } else {
need_newpathbuf = 0;
+ }
if (need_newpathbuf) {
MALLOC_ZONE(cp, char *, MAXPATHLEN, M_NAMEI, M_WAITOK);
} else {
cp = cnp->cn_pnbuf;
}
- auio = uio_createwithbuffer(1, 0, UIO_SYSSPACE, UIO_READ, &uio_buf[0], sizeof(uio_buf));
+ auio = uio_createwithbuffer(1, 0, UIO_SYSSPACE, UIO_READ,
+ &u_uio_buf.uio_buf[0], sizeof(u_uio_buf.uio_buf));
uio_addiov(auio, CAST_USER_ADDR_T(cp), MAXPATHLEN);
error = VNOP_READLINK(ndp->ni_vp, auio, ctx);
if (error) {
- if (need_newpathbuf)
+ if (need_newpathbuf) {
FREE_ZONE(cp, MAXPATHLEN, M_NAMEI);
+ }
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);
- 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);
+ }
return ENAMETOOLONG;
}
cnp->cn_pnbuf = cp;
cnp->cn_pnlen = MAXPATHLEN;
- if ( (cnp->cn_flags & HASBUF) )
+ if ((cnp->cn_flags & HASBUF)) {
FREE_ZONE(tmppn, len, M_NAMEI);
- else
+ } else {
cnp->cn_flags |= HASBUF;
- } else
+ }
+ } else {
cnp->cn_pnbuf[linklen] = '\0';
+ }
ndp->ni_pathlen += linklen;
cnp->cn_nameptr = cnp->cn_pnbuf;
* get rid of references returned via 'lookup'
*/
vnode_put(ndp->ni_vp);
- vnode_put(ndp->ni_dvp); /* ALWAYS have a dvp for a symlink */
+ vnode_put(ndp->ni_dvp); /* ALWAYS have a dvp for a symlink */
ndp->ni_vp = NULLVP;
ndp->ni_dvp = NULLVP;
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 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.
*/
- wantparent = cnp->cn_flags & (LOCKPARENT|WANTPARENT);
+ wantparent = cnp->cn_flags & (LOCKPARENT | WANTPARENT);
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;
error = ENOTDIR;
goto bad;
}
- if ( (vnode_get(dp)) ) {
- error = ENOENT;
+ if ((vnode_get(dp))) {
+ error = ENOENT;
goto bad;
}
*vpp = dp;
- if (cnp->cn_flags & SAVESTART)
+ if (cnp->cn_flags & SAVESTART) {
panic("lookup: SAVESTART");
- return (0);
+ }
+ return 0;
}
/*
* 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;
+ }
#if DIAGNOSTIC
- if (*vpp != NULL)
+ if (*vpp != NULL) {
panic("leaf should be empty");
+ }
#endif
/*
* If creating and at end of pathname, then can consider
* doesn't currently exist, leaving a pointer to the
* (possibly locked) directory inode in ndp->ni_dvp.
*/
- return (0);
+ return 0;
}
dp = *vpp;
/*
* 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
/*
goto bad2;
}
/* ASSERT(dvp == ndp->ni_startdir) */
-
- return (0);
+
+ return 0;
bad2:
vnode_put(dp);
-bad:
+bad:
*vpp = NULL;
- return (error);
-}
-
-void
-namei_unlock_fsnode(struct nameidata *ndp)
-{
-#ifndef __LP64__
- if ((ndp->ni_cnd.cn_flags & FSNODELOCKHELD)) {
- ndp->ni_cnd.cn_flags &= ~FSNODELOCKHELD;
- unlock_fsnode(ndp->ni_dvp, NULL);
- }
-#else
- (void)ndp;
-#endif /* __LP64__ */
+ return error;
}
/*
void
nameidone(struct nameidata *ndp)
{
- namei_unlock_fsnode(ndp);
-
if (ndp->ni_cnd.cn_flags & HASBUF) {
char *tmp = ndp->ni_cnd.cn_pnbuf;
}
-#define NUMPARMS 23
-
/*
* Log (part of) a pathname using the KERNEL_DEBUG_CONSTANT mechanism, as used
* by fs_usage. The path up to and including the current component name are
* fails because /foo_bar_baz is not found will only log "/foo_bar_baz", with
* no '>' padding. But /foo_bar/spam would log "/foo_bar>>>>".
*/
-#if !defined(NO_KDEBUG)
-static void
-kdebug_lookup(struct vnode *dp, struct componentname *cnp)
+#if (KDEBUG_LEVEL >= KDEBUG_LEVEL_IST)
+
+void
+kdebug_vfs_lookup(long *dbg_parms, int dbg_namelen, void *dp, uint32_t flags)
{
- 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.
+ */
+ if (lookup) {
+ code = VFS_LOOKUP | DBG_FUNC_START;
+ } else {
+ code = VFS_LOOKUP_DONE | DBG_FUNC_START;
+ }
+
+ if (dbg_namelen <= (int)(3 * sizeof(long))) {
+ code |= DBG_FUNC_END;
+ }
+
+ 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;
+
+ 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;
+ }
+
+ 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]);
+ }
+ }
+}
+
+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;
char *dbg_nameptr;
long dbg_parms[NUMPARMS];
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_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,
- *(cnp->cn_nameptr + cnp->cn_namelen) ? '>' : 0,
- sizeof(dbg_parms) - dbg_namelen);
+ *(cnp->cn_nameptr + cnp->cn_namelen) ? '>' : 0,
+ sizeof(dbg_parms) - dbg_namelen);
}
-
- /*
- * In the event that we collect multiple, consecutive pathname
- * entries, we must mark the start of the path's string and the end.
- */
- code = (FSDBG_CODE(DBG_FSRW,36)) | DBG_FUNC_START;
-
- if (dbg_namelen <= 12)
- code |= DBG_FUNC_END;
-
- KERNEL_DEBUG_CONSTANT(code, dp, dbg_parms[0], dbg_parms[1], dbg_parms[2], 0);
-
- code &= ~DBG_FUNC_START;
+ kdebug_vfs_lookup(dbg_parms, dbg_namelen, (void *)dp,
+ KDBG_VFS_LOOKUP_FLAG_LOOKUP);
+}
- for (i=3, dbg_namelen -= 12; dbg_namelen > 0; i+=4, dbg_namelen -= 16) {
- if (dbg_namelen <= 16)
- code |= DBG_FUNC_END;
+#else /* (KDEBUG_LEVEL >= KDEBUG_LEVEL_IST) */
- KERNEL_DEBUG_CONSTANT(code, dbg_parms[i], dbg_parms[i+1], dbg_parms[i+2], dbg_parms[i+3], 0);
- }
+void
+kdebug_vfs_lookup(long *dbg_parms __unused, int dbg_namelen __unused,
+ void *dp __unused, __unused uint32_t flags)
+{
}
-#else /* NO_KDEBUG */
+
static void
kdebug_lookup(struct vnode *dp __unused, struct componentname *cnp __unused)
{
}
-#endif /* NO_KDEBUG */
+#endif /* (KDEBUG_LEVEL >= KDEBUG_LEVEL_IST) */
int
vfs_getbyid(fsid_t *fsid, ino64_t ino, vnode_t *vpp, vfs_context_t ctx)
{
mount_t mp;
int error;
-
+
mp = mount_lookupby_volfsid(fsid->val[0], 1);
if (mp == NULL) {
return EINVAL;
/* 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++;
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') {
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) {
- 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);
}
if (error == 0 && *str != '\0') {
int attempt = strlcat(realpath, str, MAXPATHLEN);
- if (attempt > MAXPATHLEN){
+ if (attempt > MAXPATHLEN) {
error = ENAMETOOLONG;
}
}
out:
- return (error);
+ return error;
}
#endif
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.
return;
}
- /*
+ /*
* If we're going to continue the lookup, we'll handle
* all lookup-related updates at that time.
*/
* 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);
}
- if (ndp->ni_cnd.cn_flags & AUDITVNPATH1)
+ if (ndp->ni_cnd.cn_flags & AUDITVNPATH1) {
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);
+ }
}
- /*
- * 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:
- * 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) {
- kdebug_lookup(vp ? vp : dvp, &ndp->ni_cnd);
+ kdebug_lookup(vp ? vp : dvp, &ndp->ni_cnd);
}
}
projects / apple / xnu.git / blobdiff