[src/trunk]: src/sys/kern in sbsavetimestamp(), initialize struct timeval to ...

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

details:   https://anonhg.NetBSD.org/src/rev/6c75e9a7d6b8
branches:  trunk
changeset: 1022730:6c75e9a7d6b8
user:      chs <chs%NetBSD.org@localhost>
date:      Tue Aug 03 20:27:08 2021 +0000

description:
in sbsavetimestamp(), initialize struct timeval to 0 with memset() so that
the implicit padding is initialized.  this avoids later copying uninitialized
memory out to user space.  detected by KMSAN.

diffstat:

 sys/kern/uipc_socket.c |  5 +++--
 1 files changed, 3 insertions(+), 2 deletions(-)

diffs (26 lines):

diff -r 33eddad22bde -r 6c75e9a7d6b8 sys/kern/uipc_socket.c
--- a/sys/kern/uipc_socket.c    Tue Aug 03 20:25:43 2021 +0000
+++ b/sys/kern/uipc_socket.c    Tue Aug 03 20:27:08 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: uipc_socket.c,v 1.294 2020/12/11 03:00:09 thorpej Exp $        */
+/*     $NetBSD: uipc_socket.c,v 1.295 2021/08/03 20:27:08 chs Exp $    */
 
 /*
  * Copyright (c) 2002, 2007, 2008, 2009 The NetBSD Foundation, Inc.
@@ -71,7 +71,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: uipc_socket.c,v 1.294 2020/12/11 03:00:09 thorpej Exp $");
+__KERNEL_RCSID(0, "$NetBSD: uipc_socket.c,v 1.295 2021/08/03 20:27:08 chs Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_compat_netbsd.h"
@@ -2432,6 +2432,7 @@
        struct timeval tv;
        int error;
 
+       memset(&tv, 0, sizeof(tv));
        microtime(&tv);
 
        MODULE_HOOK_CALL(uipc_socket_50_sbts_hook, (opt, &mp), enosys(), error);