No reliable way to configure MAC address spoofing

[Krzysztof Kosinski]

In Ubuntu 14.04.1 LTS there is no way to configure MAC address spoofing, at least when using the r8168 driver.

Here are the symptoms that I observe:

1. When trying to use the Network Manager applet to assign a static IP and a cloned MAC address, the connection fails and there is no network connectivity. It doesn't matter whether I fill both the Device MAC Address and the Cloned MAC Address fields, or only the Cloned MAC Address, the result is the same.

2. When using /etc/network/interfaces with the "hwaddress ether aa:bb:cc:dd:ee:ff" stanza, the connection is not brought up correctly after reboot or after the cable is unplugged and plugged back in. It only works when I manually type in "sudo ifup eth0", which is unacceptable on a server. As far as I can tell, this might be caused by udev 'losing track' of the device due to the changed MAC address and not running ifup / ifdown scripts in response to kernel events, so I'm submitting this as a bug in systemd.

3. When MAC address spoofing is not used, both of these ways work correctly and network connectivity is correctly re-established after reboot and cable unplug.

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: udev 204-5ubuntu20.3
ProcVersionSignature: Ubuntu 3.13.0-32.57-generic 3.13.11.4
Uname: Linux 3.13.0-32-generic x86_64
ApportVersion: 2.14.1-0ubuntu3.2
Architecture: amd64
CurrentDmesg:
 [ 15.533193] init: plymouth-stop pre-start process (2031) terminated with status 1
 [ 36.382964] audit_printk_skb: 132 callbacks suppressed
 [ 36.382967] type=1400 audit(1407338565.893:66): apparmor="STATUS" operation="profile_replace" profile="unconfined" name="/usr/lib/cups/backend/cups-pdf" pid=3195 comm="apparmor_parser"
 [ 36.382972] type=1400 audit(1407338565.893:67): apparmor="STATUS" operation="profile_replace" profile="unconfined" name="/usr/sbin/cupsd" pid=3195 comm="apparmor_parser"
 [ 36.383292] type=1400 audit(1407338565.893:68): apparmor="STATUS" operation="profile_replace" profile="unconfined" name="/usr/sbin/cupsd" pid=3195 comm="apparmor_parser"
Date: Wed Aug 6 23:18:48 2014
InstallationDate: Installed on 2014-06-16 (51 days ago)
InstallationMedia: Ubuntu-Server 14.04 LTS "Trusty Tahr" - Release amd64 (20140416.2)
MachineType: To be filled by O.E.M. To be filled by O.E.M.
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.13.0-32-generic.efi.signed root=UUID=2cca6090-764f-4f6d-8c18-ec50f8085100 ro text nomdmonddf nomdmonisw
SourcePackage: systemd
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 04/08/2014
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 2501
dmi.board.asset.tag: To be filled by O.E.M.
dmi.board.name: SABERTOOTH 990FX R2.0
dmi.board.vendor: ASUSTeK COMPUTER INC.
dmi.board.version: Rev 1.xx
dmi.chassis.asset.tag: To Be Filled By O.E.M.
dmi.chassis.type: 3
dmi.chassis.vendor: To Be Filled By O.E.M.
dmi.chassis.version: To Be Filled By O.E.M.
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr2501:bd04/08/2014:svnTobefilledbyO.E.M.:pnTobefilledbyO.E.M.:pvrTobefilledbyO.E.M.:rvnASUSTeKCOMPUTERINC.:rnSABERTOOTH990FXR2.0:rvrRev1.xx:cvnToBeFilledByO.E.M.:ct3:cvrToBeFilledByO.E.M.:
dmi.product.name: To be filled by O.E.M.
dmi.product.version: To be filled by O.E.M.
dmi.sys.vendor: To be filled by O.E.M.

[Martin Pitt (pitti)]

The only thing that udev does in this context is to rename network interfaces, in /etc/udev/rules.d/70-persistent-net.rules (that's autogenerated on install). So if you change the MACs you probably need to delete/disable the file, or your network interfaces will come back with a different name. With NetworkManager that won't matter, but if you use ifupdown, i. e. /etc/network/interfaces then the name mismatch will break things.

Please attach the output of "dmesg" after a complete "boot, change MAC, replug" cycle, and the ouptut of "ip a" before and after changing the MAC. Please also try with moving /etc/udev/rules.d/70-persistent-net.rules aside (if you only have one ethernet device it's not necessary anyway).

[Launchpad Janitor (janitor)]

[Expired for systemd (Ubuntu) because there has been no activity for 60 days.]

[Abhilash Anandan (abhilash24692)]

I still have this problem. It is very annoying. Is there anything I can do to help get it fixed?