[src/trunk]: src/sys/netinet6 Avoid NULL pointer dereference, noticed by KUBSAN.

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

details:   https://anonhg.NetBSD.org/src/rev/6a71de8e7207
branches:  trunk
changeset: 948316:6a71de8e7207
user:      nia <nia%NetBSD.org@localhost>
date:      Sat Dec 26 10:43:39 2020 +0000

description:
Avoid NULL pointer dereference, noticed by KUBSAN.

"Looks fine" roy@

diffstat:

 sys/netinet6/nd6.c |  8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)

diffs (29 lines):

diff -r 1daeae4e09c9 -r 6a71de8e7207 sys/netinet6/nd6.c
--- a/sys/netinet6/nd6.c        Sat Dec 26 08:58:03 2020 +0000
+++ b/sys/netinet6/nd6.c        Sat Dec 26 10:43:39 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: nd6.c,v 1.274 2020/09/15 10:05:36 roy Exp $    */
+/*     $NetBSD: nd6.c,v 1.275 2020/12/26 10:43:39 nia Exp $    */
 /*     $KAME: nd6.c,v 1.279 2002/06/08 11:16:51 itojun Exp $   */
 
 /*
@@ -31,7 +31,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: nd6.c,v 1.274 2020/09/15 10:05:36 roy Exp $");
+__KERNEL_RCSID(0, "$NetBSD: nd6.c,v 1.275 2020/12/26 10:43:39 nia Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_compat_netbsd.h"
@@ -384,8 +384,8 @@
     const union l3addr *hsrc)
 {
 
-       nd6_ns_output(ifp, &daddr->addr6, &taddr->addr6,
-           &hsrc->addr6, NULL);
+       nd6_ns_output(ifp, daddr != NULL ? &daddr->addr6 : NULL,
+           &taddr->addr6, &hsrc->addr6, NULL);
 }
 
 static bool