- Remove an unused variable from relookup().

 - Assert that REMOVE, CREATE, and RENAME callers have WANTPARENT
   or LOCKPARENT set.  You can't complete any of these operations without
   at least a reference to the parent.  Many filesystems check for this case
   even though it isn't possible in the current system.

1 files changed, 2 insertions, 5 deletions

diff --git a/sys/kern/vfs_lookup.c b/sys/kern/vfs_lookup.c
index 6596eb9..6b8b806 100644
--- a/sys/kern/vfs_lookup.c
+++ b/sys/kern/vfs_lookup.c
@@ -352,6 +352,8 @@ lookup(ndp)
 	vfslocked = (ndp->ni_cnd.cn_flags & GIANTHELD) != 0;
 	ndp->ni_cnd.cn_flags &= ~GIANTHELD;
 	wantparent = cnp->cn_flags & (LOCKPARENT | WANTPARENT);
+	KASSERT(cnp->cn_nameiop == LOOKUP || wantparent,
+	    ("CREATE, DELETE, RENAME require LOCKPARENT or WANTPARENT."));
 	docache = (cnp->cn_flags & NOCACHE) ^ NOCACHE;
 	if (cnp->cn_nameiop == DELETE ||
 	    (wantparent && cnp->cn_nameiop != CREATE &&
@@ -710,7 +712,6 @@ relookup(dvp, vpp, cnp)
 {
 	struct thread *td = cnp->cn_thread;
 	struct vnode *dp = 0;		/* the directory we are searching */
-	int docache;			/* == 0 do not cache last component */
 	int wantparent;			/* 1 => wantparent or lockparent flag */
 	int rdonly;			/* lookup read-only flag bit */
 	int error = 0;
@@ -721,10 +722,6 @@ relookup(dvp, vpp, cnp)
 	 * Setup: break out flag bits into variables.
 	 */
 	wantparent = cnp->cn_flags & (LOCKPARENT|WANTPARENT);
-	docache = (cnp->cn_flags & NOCACHE) ^ NOCACHE;
-	if (cnp->cn_nameiop == DELETE ||
-	    (wantparent && cnp->cn_nameiop != CREATE))
-		docache = 0;
 	rdonly = cnp->cn_flags & RDONLY;
 	cnp->cn_flags &= ~ISSYMLINK;
 	dp = dvp;