[src/trunk]: src/sys/arch/xen/xen make the packet length check less strict, a...

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

details:   https://anonhg.NetBSD.org/src/rev/89de4fd2e4ed
branches:  trunk
changeset: 1008185:89de4fd2e4ed
user:      jdolecek <jdolecek%NetBSD.org@localhost>
date:      Sat Mar 14 11:52:12 2020 +0000

description:
make the packet length check less strict, allow the physical packet longer
than IP payload

this fixes problem where checksum was not recomputed for short
packets coming from Windows DOMU on same physical host, seems Windows
does some padding; reported by sborrill@

XXX pullup-9

diffstat:

 sys/arch/xen/xen/xennet_checksum.c |  6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)

diffs (27 lines):

diff -r 2ca5a18326ca -r 89de4fd2e4ed sys/arch/xen/xen/xennet_checksum.c
--- a/sys/arch/xen/xen/xennet_checksum.c        Sat Mar 14 09:01:11 2020 +0000
+++ b/sys/arch/xen/xen/xennet_checksum.c        Sat Mar 14 11:52:12 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: xennet_checksum.c,v 1.3 2007/11/22 16:17:10 bouyer Exp $       */
+/*     $NetBSD: xennet_checksum.c,v 1.4 2020/03/14 11:52:12 jdolecek Exp $     */
 
 /*-
  * Copyright (c)2006 YAMAMOTO Takashi,
@@ -27,7 +27,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: xennet_checksum.c,v 1.3 2007/11/22 16:17:10 bouyer Exp $");
+__KERNEL_RCSID(0, "$NetBSD: xennet_checksum.c,v 1.4 2020/03/14 11:52:12 jdolecek Exp $");
 
 #include <sys/types.h>
 #include <sys/param.h>
@@ -124,7 +124,7 @@
        nxt = iph->ip_p;
        iphlen = iph->ip_hl * 4;
        iplen = ntohs(iph->ip_len);
-       if (ehlen + iplen != m->m_pkthdr.len) {
+       if (ehlen + iplen > m->m_pkthdr.len) {
                return EINVAL;
        }
        if (nxt == IPPROTO_UDP) {