[src/trunk]: src/sys/dev/usb Check buffer length before copy.

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

details:   https://anonhg.NetBSD.org/src/rev/5985ca190915
branches:  trunk
changeset: 835584:5985ca190915
user:      rin <rin%NetBSD.org@localhost>
date:      Thu Aug 30 09:59:12 2018 +0000

description:
Check buffer length before copy.

diffstat:

 sys/dev/usb/if_mue.c |  8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)

diffs (32 lines):

diff -r ce3cf28988dd -r 5985ca190915 sys/dev/usb/if_mue.c
--- a/sys/dev/usb/if_mue.c      Thu Aug 30 09:00:08 2018 +0000
+++ b/sys/dev/usb/if_mue.c      Thu Aug 30 09:59:12 2018 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: if_mue.c,v 1.3 2018/08/30 09:00:08 rin Exp $   */
+/*     $NetBSD: if_mue.c,v 1.4 2018/08/30 09:59:12 rin Exp $   */
 /*     $OpenBSD: if_mue.c,v 1.3 2018/08/04 16:42:46 jsg Exp $  */
 
 /*
@@ -20,7 +20,7 @@
 /* Driver for Microchip LAN7500/LAN7800 chipsets. */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_mue.c,v 1.3 2018/08/30 09:00:08 rin Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_mue.c,v 1.4 2018/08/30 09:59:12 rin Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_usb.h"
@@ -1229,11 +1229,11 @@
        memcpy(c->mue_buf, &hdr, sizeof(hdr)); 
        len = sizeof(hdr);
 
+       KASSERT(len + m->m_pkthdr.len <= sc->mue_txbufsz);
+
        m_copydata(m, 0, m->m_pkthdr.len, c->mue_buf + len);
        len += m->m_pkthdr.len;
 
-       KASSERT(len <= sc->mue_txbufsz);
-
        usbd_setup_xfer(c->mue_xfer, c, c->mue_buf, len,
            USBD_FORCE_SHORT_XFER, 10000, mue_txeof);