[src/trunk]: src/sys/kern Add a sanity check to ensure that a region being fr...

[thorpej <thorpej%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/f6b029de0a31
branches:  trunk
changeset: 481540:f6b029de0a31
user:      thorpej <thorpej%NetBSD.org@localhost>
date:      Tue Feb 01 19:37:58 2000 +0000

description:
Add a sanity check to ensure that a region being free()'d is actually
within the KVA range malloc() would return.

diffstat:

 sys/kern/kern_malloc.c |  13 ++++++++++++-
 1 files changed, 12 insertions(+), 1 deletions(-)

diffs (27 lines):

diff -r 05b679377120 -r f6b029de0a31 sys/kern/kern_malloc.c
--- a/sys/kern/kern_malloc.c    Tue Feb 01 19:29:33 2000 +0000
+++ b/sys/kern/kern_malloc.c    Tue Feb 01 19:37:58 2000 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: kern_malloc.c,v 1.47 1999/12/03 21:43:20 ragge Exp $   */
+/*     $NetBSD: kern_malloc.c,v 1.48 2000/02/01 19:37:58 thorpej Exp $ */
 
 /*
  * Copyright (c) 1996 Christopher G. Demetriou.  All rights reserved.
@@ -405,6 +405,17 @@
        register struct kmemstats *ksp = &kmemstats[type];
 #endif
 
+#ifdef DIAGNOSTIC
+       /*
+        * Ensure that we're free'ing something that we could
+        * have allocated in the first place.  That is, check
+        * to see that the address is within kmem_map.
+        */
+       if ((vaddr_t)addr < kmem_map->header.start ||
+           (vaddr_t)addr >= kmem_map->header.end)
+               panic("free: addr %p not within kmem_map", addr);
+#endif
+
        kup = btokup(addr);
        size = 1 << kup->ku_indx;
        kbp = &bucket[kup->ku_indx];