[src/trunk]: src/sys/dev/usb rum(4): Avoid uninitialized garbage in failed re...

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

details:   https://anonhg.NetBSD.org/src/rev/a282534b8a72
branches:  trunk
changeset: 368919:a282534b8a72
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Fri Aug 12 19:13:36 2022 +0000

description:
rum(4): Avoid uninitialized garbage in failed register read.

Reported-by: syzbot+f2cba71b1b1bc91029b3%syzkaller.appspotmail.com@localhost
https://syzkaller.appspot.com/bug?id=7a01863d0fe34a4946516388c436991ba2beaa63

diffstat:

 sys/dev/usb/if_rum.c |  6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)

diffs (35 lines):

diff -r a6e2fdbb25ba -r a282534b8a72 sys/dev/usb/if_rum.c
--- a/sys/dev/usb/if_rum.c      Fri Aug 12 17:06:01 2022 +0000
+++ b/sys/dev/usb/if_rum.c      Fri Aug 12 19:13:36 2022 +0000
@@ -1,5 +1,5 @@
 /*     $OpenBSD: if_rum.c,v 1.40 2006/09/18 16:20:20 damien Exp $      */
-/*     $NetBSD: if_rum.c,v 1.69 2020/03/15 23:04:50 thorpej Exp $      */
+/*     $NetBSD: if_rum.c,v 1.70 2022/08/12 19:13:36 riastradh Exp $    */
 
 /*-
  * Copyright (c) 2005-2007 Damien Bergamini <damien.bergamini%free.fr@localhost>
@@ -24,7 +24,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_rum.c,v 1.69 2020/03/15 23:04:50 thorpej Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_rum.c,v 1.70 2022/08/12 19:13:36 riastradh Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_usb.h"
@@ -1407,6 +1407,7 @@
        if (error != 0) {
                printf("%s: could not read EEPROM: %s\n",
                    device_xname(sc->sc_dev), usbd_errstr(error));
+               memset(buf, 0, len);
        }
 }
 
@@ -1436,6 +1437,7 @@
        if (error != 0) {
                printf("%s: could not multi read MAC register: %s\n",
                    device_xname(sc->sc_dev), usbd_errstr(error));
+               memset(buf, 0, len);
        }
 }