[src/trunk]: src/usr.sbin/intrctl fix intrctl_io_firstline() to properly retu...

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

details:   https://anonhg.NetBSD.org/src/rev/65b3a5ecb669
branches:  trunk
changeset: 320110:65b3a5ecb669
user:      jdolecek <jdolecek%NetBSD.org@localhost>
date:      Sat Jun 23 11:11:00 2018 +0000

description:
fix intrctl_io_firstline() to properly return NULL if there are no records
to show

diffstat:

 usr.sbin/intrctl/intrctl_io.c |  13 ++++++++++---
 1 files changed, 10 insertions(+), 3 deletions(-)

diffs (35 lines):

diff -r 6d0993f7662a -r 65b3a5ecb669 usr.sbin/intrctl/intrctl_io.c
--- a/usr.sbin/intrctl/intrctl_io.c     Sat Jun 23 10:30:22 2018 +0000
+++ b/usr.sbin/intrctl/intrctl_io.c     Sat Jun 23 11:11:00 2018 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: intrctl_io.c,v 1.3 2016/08/05 06:58:55 knakahara Exp $ */
+/*     $NetBSD: intrctl_io.c,v 1.4 2018/06/23 11:11:00 jdolecek Exp $  */
 
 /*
  * Copyright (c) 2015 Internet Initiative Japan Inc.
@@ -27,7 +27,7 @@
  */
 
 #include <sys/cdefs.h>
-__RCSID("$NetBSD: intrctl_io.c,v 1.3 2016/08/05 06:58:55 knakahara Exp $");
+__RCSID("$NetBSD: intrctl_io.c,v 1.4 2018/06/23 11:11:00 jdolecek Exp $");
 
 #include <sys/sysctl.h>
 #include <sys/intrio.h>
@@ -108,8 +108,15 @@
 intrctl_io_firstline(void *handle)
 {
        struct intrio_list *list = handle;
+       struct intrio_list_line *next;
+       char *buf_end;
 
-       return (struct intrio_list_line *)((char *)list + list->il_lineoffset);
+       buf_end = (char *)list + list->il_bufsize;
+       next = (struct intrio_list_line *)((char *)list + list->il_lineoffset);
+       if ((char *)next >= buf_end)
+               return NULL;
+
+       return next;
 }
 
 struct intrio_list_line *