Index: sys/kern/vfs_lookup.c
===================================================================
--- sys/kern/vfs_lookup.c (revision 200583)
+++ sys/kern/vfs_lookup.c (working copy)
@@ -552,6 +552,12 @@ dirloop:
else
cnp->cn_flags &= ~ISLASTCN;
+ if ((cnp->cn_flags & ISLASTCN) != 0 &&
+ cnp->cn_namelen == 1 && cnp->cn_nameptr[0] == '.' &&
+ (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME)) {
+ error = EINVAL;
+ goto bad;
+ }
/*
* Check for degenerate name (e.g. / or "")
