/*
- * Copyright (c) 2000-2011 Apple Inc. All rights reserved.
+ * Copyright (c) 2000-2015 Apple Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
#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
#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,
+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);
-int lookup_handle_emptyname(struct nameidata *ndp, struct componentname *cnp, int wantparent);
+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
if ( (error = lookup(ndp)) ) {
goto error_out;
}
+
/*
* Check for symbolic link
*/
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
return 0;
}
-void
+static void
lookup_consider_update_cache(vnode_t dvp, vnode_t vp, struct componentname *cnp, int nc_generation)
{
int isdot_or_dotdot;
* 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;
* --In the event of an error, may return with ni_dvp NULL'ed out (in which case, iocount
* was dropped).
*/
-int
+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)
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.
/*
* 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;
/*
* 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;
/*
* Modifies only ni_vp. Always returns with ni_vp still valid (iocount held).
*/
-int
+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;
int current_mount_generation = 0;
+#if CONFIG_TRIGGERS
+ vnode_t triggered_dp = NULLVP;
+ int retry_cnt = 0;
+#define MAX_TRIGGER_RETRIES 1
+#endif
- mounted_on_dp = dp;
- current_mount_generation = mount_generation;
-
- while ((dp->v_type == VDIR) && dp->v_mountedhere &&
- ((cnp->cn_flags & NOCROSSMOUNT) == 0)) {
+ if (dp->v_type != VDIR || cnp->cn_flags & NOCROSSMOUNT)
+ return 0;
- if (dp->v_mountedhere->mnt_lflag & MNT_LFORCE) {
- break; // don't traverse into a forced unmount
- }
+ mounted_on_dp = dp;
#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);
- }
+restart:
#endif
- vnode_lock(dp);
-
- if ((dp->v_type == VDIR) && (mp = dp->v_mountedhere)) {
+ 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;
- }
-
-
- /*
- * 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;
+ if (vfs_busy(mp, vbusyflags)) {
mount_dropcrossref(mp, dp, 0);
- vfs_unbusy(mp);
-
- if (error) {
+ if (vbusyflags == LK_NOWAIT) {
+ error = ENOENT;
goto out;
}
- vnode_put(dp);
- ndp->ni_vp = dp = tdp;
- depth++;
+ continue;
+ }
-#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
+ error = VFS_ROOT(mp, &tdp, ctx);
- } else {
- vnode_unlock(dp);
+ mount_dropcrossref(mp, dp, 0);
+ vfs_unbusy(mp);
+
+ if (error) {
+ goto out;
+ }
+
+ 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 (depth && !dont_cache_mp) {
+#if CONFIG_TRIGGERS
+ /*
+ * 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) {
mp = mounted_on_dp->v_mountedhere;
if (mp) {
* 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;
* entries, we must mark the start of the path's string and the end.
*/
if (lookup == TRUE)
- code = (FSDBG_CODE(DBG_FSRW,36)) | DBG_FUNC_START;
+ code = VFS_LOOKUP | DBG_FUNC_START;
else
- code = (FSDBG_CODE(DBG_FSRW,39)) | DBG_FUNC_START;
+ code = VFS_LOOKUP_DONE | DBG_FUNC_START;
if (dbg_namelen <= (int)(3 * sizeof(long)))
code |= DBG_FUNC_END;
projects / apple / xnu.git / blobdiff