From 1892b8956115bef5ef6b4c0bb6f93d3fd16edc04 Mon Sep 17 00:00:00 2001
From: kib <kib@FreeBSD.org>
Date: Wed, 21 Jun 2017 18:51:30 +0000
Subject: [PATCH] Assert that the protection of a new map entry is a subset of
 the max protection.

Noted and reviewed by:	alc
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
---
 sys/vm/vm_map.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/sys/vm/vm_map.c b/sys/vm/vm_map.c
index cbbd9762c90d..86d17aeddea6 100644
--- a/sys/vm/vm_map.c
+++ b/sys/vm/vm_map.c
@@ -1190,6 +1190,8 @@ vm_map_insert(vm_map_t map, vm_object_t object, vm_ooffset_t offset,
 	    ("vm_map_insert: kmem or kernel object and COW"));
 	KASSERT(object == NULL || (cow & MAP_NOFAULT) == 0,
 	    ("vm_map_insert: paradoxical MAP_NOFAULT request"));
+	KASSERT((prot & ~max) == 0,
+	    ("prot %#x is not subset of max_prot %#x", prot, max));
 
 	/*
 	 * Check that the start and end points are not bogus.