[src/trunk]: src/lib/libc/stdlib die if integer overflow. from openbsd

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

details:   https://anonhg.NetBSD.org/src/rev/41f8f47c9397
branches:  trunk
changeset: 534598:41f8f47c9397
user:      itojun <itojun%NetBSD.org@localhost>
date:      Tue Jul 30 09:45:02 2002 +0000

description:
die if integer overflow.  from openbsd

diffstat:

 lib/libc/stdlib/calloc.c |  10 ++++++++--
 1 files changed, 8 insertions(+), 2 deletions(-)

diffs (36 lines):

diff -r c6d2fe94aa9c -r 41f8f47c9397 lib/libc/stdlib/calloc.c
--- a/lib/libc/stdlib/calloc.c  Tue Jul 30 09:11:27 2002 +0000
+++ b/lib/libc/stdlib/calloc.c  Tue Jul 30 09:45:02 2002 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: calloc.c,v 1.9 1998/02/03 18:44:14 perry Exp $ */
+/*     $NetBSD: calloc.c,v 1.10 2002/07/30 09:45:02 itojun Exp $       */
 
 /*-
  * Copyright (c) 1990, 1993
@@ -38,12 +38,14 @@
 #if 0
 static char sccsid[] = "@(#)calloc.c   8.1 (Berkeley) 6/4/93";
 #else
-__RCSID("$NetBSD: calloc.c,v 1.9 1998/02/03 18:44:14 perry Exp $");
+__RCSID("$NetBSD: calloc.c,v 1.10 2002/07/30 09:45:02 itojun Exp $");
 #endif
 #endif /* LIBC_SCCS and not lint */
 
 #include <stdlib.h>
 #include <string.h>
+#include <limits.h>
+#include <errno.h>
 
 void *
 calloc(num, size)
@@ -52,6 +54,10 @@
 {
        void *p;
 
+       if (SIZE_T_MAX / num < size) {
+               errno = ENOMEM;
+               return NULL;
+       }
        size *= num;
        if ((p = malloc(size)) != NULL)
                memset(p, '\0', size);