Fix some gibbering horrors due to uninitialized struct nameidata's

1) turn NDINITAT into a function and make the macros point to it
with the later goal of getting rid of them.

2) Sweep the kernel for places where people make a struct nameidata manually
on the stack and fill in what they hope are the required fields and count
on prayer and clean living to always get them right. Instead use NDINIT
everywhere. NFS was especially bad for this and there have likely
been things lurking there for a while.

3) Add a couple of strategic KASSERT's to catch future offenders.

ok krw@ sthen@ deraadt@

1 files changed, 8 insertions, 1 deletions

diff --git a/sys/nfs/nfs_subs.c b/sys/nfs/nfs_subs.c
index 97f7d6e8352..35ad17e64fb 100644
--- a/sys/nfs/nfs_subs.c
+++ b/sys/nfs/nfs_subs.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: nfs_subs.c,v 1.130 2016/03/19 12:04:16 natano Exp $	*/
+/*	$OpenBSD: nfs_subs.c,v 1.131 2016/04/29 14:40:36 beck Exp $	*/
 /*	$NetBSD: nfs_subs.c,v 1.27.4.3 1996/07/08 20:34:24 jtc Exp $	*/
 
 /*
@@ -1244,6 +1244,13 @@ nfs_namei(struct nameidata *ndp, fhandle_t *fhp, int len,
 		cnp->cn_flags |= (NOCROSSMOUNT | RDONLY);
 	else
 		cnp->cn_flags |= NOCROSSMOUNT;
+
+	/*
+	 * Should be 0, if not someone didn't init ndp with NDINIT,
+	 * go find and murder the offender messily.
+	 */
+	KASSERT (ndp->ni_p_path == NULL && ndp->ni_p_size == 0);
+
 	/*
 	 * And call lookup() to do the real work
 	 */