kern/140712: fxp driver starts with rxcsum on

[Jared Mauch]

>Number:         140712
>Category:       kern
>Synopsis:       fxp driver starts with rxcsum on
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Fri Nov 20 01:50:01 UTC 2009
>Closed-Date:
>Last-Modified:
>Originator:     Jared Mauch
>Release:        FreeBSD 8.0-RC3 i386
>Organization:
Self
>Environment:
FreeBSD npd2.nether.net 8.0-RC3 FreeBSD 8.0-RC3 #0: Tue Nov 10 07:50:36 UTC 2009     root at almeida.cse.buffalo.edu:/usr/obj/usr/src/sys/GENERIC  i386


	
>Description:
	Upon upgrading from 7.0-release to 8.0-RC3 the fxp0 interface came with rxcsum enabled, eg:

# ifconfig fxp0
fxp0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
	options=9<RXCSUM,VLAN_MTU>
	ether 00:20:fc:1e:dd:00
	inet 61.120.147.50 netmask 0xfffffffc broadcast 61.120.147.51
	inet6 fe80::220:fcff:fe1e:dd00%fxp0 prefixlen 64 scopeid 0x1 
	media: Ethernet 100baseTX <full-duplex>
	status: active
# sysctl -a | grep fxp
dev.fxp.0.%desc: Intel 82559ER Embedded 10/100 Ethernet
dev.fxp.0.%driver: fxp
dev.fxp.0.%location: slot=4 function=0
dev.fxp.0.%pnpinfo: vendor=0x8086 device=0x1209 subvendor=0x102b subdevice=0x6000 class=0x020000
dev.fxp.0.%parent: pci3
dev.fxp.0.int_delay: 1000
dev.fxp.0.bundle_max: 6
dev.fxp.0.rnr: 0
dev.fxp.0.noflow: 1

	This caused truncated IP packets/messages to be received by the kernel resulting in the machine being unreachable.


# tcpdump -n -i fxp0 -c 3 -s0
fxp0: promiscuous mode enabled
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on fxp0, link-type EN10MB (Ethernet), capture size 65535 bytes
01:52:48.166315 IP truncated-ip - 2 bytes missing! 204.42.254.133 > 61.120.147.50: ICMP echo request, id 33313, seq 5139, length 64
01:52:49.166155 IP truncated-ip - 2 bytes missing! 204.42.254.133 > 61.120.147.50: ICMP echo request, id 33313, seq 5140, length 64
01:52:50.166276 fIP truncated-ip x- 2 bytes missinpg! 204.42.254.1303 > 61.120.147.5:0: ICMP echo req uest, id 33313, pseq 5141, lengthr 64
3 packets coaptured
3 packemts received by fiilter
0 packetss dropped by kerncel
uous mode disabled



>How-To-Repeat:

	Reboot the system with this hardware installed/used.
	
>Fix:

	ifconfig fxp0 -rxcsum
	


>Release-Note:
>Audit-Trail:
>Unformatted: