XCP-ng 8.3 betas and RCs feedback 🚀

stormi

Which kernel are you looking at since 4.19 will be EOL in 9 months?

So, the main blocker in the way to upgrade the kernel is a kernel module we use for storage access from the VMs. Work is being done to replace it, which will unlock the possibility to move to a newer kernel. Which version exactly will be chosen in due time. Likely a LTS kernel.

Meanwhile, XCP-ng 8.3 remains on 4.19, on which we'll continue to provide security fixes for vulnerabilities that may affect it in the context of dom0.

xerxist

@stormi

Thanks for the explanation.
Will this be added like what there is now as an alternative kernel?

stormi

@xerxist Possibly, but then only some storage drivers will work with it. This will mainly be for testing purposes and gathering feedback.

xerxist

@stormi

Not to be negative but in a professional environment auditors will trip on this. No one wants to explain to auditors that its plastered from upstream somewhere. Also it’s good for new hardware support. But good to hear work is progress.

gb.123

USB Passthrough Testing & Feedback :

Tested 2 Devices :-

16 GB USB Flash Drive - Transcend
Results : Works Perfectly
ePass2003 Token (for Digital Signatures)
Results : ~~Not Detected~~ (See update)

~~Deep Diving :~~
~~lsusb & usb-devices commands list the device (vendor id - 096e) on console (cli). However, the device is not shown in the 'Advanced' tab of the node/host.~~

~~Maybe devices getting filtered only for USB Media / Flash Drive in Xen Orchestra ?~~

Update :
Token also works now after editing : /etc/xensource/usb-policy.conf
as enumerated here.

Thanks to @olivierlambert for the above link and prompt guidance!

olivierlambert

Probably not in the white list of device type. Read https://docs.xcp-ng.org/compute/#️-usb-passthrough for more details.

gb.123

@olivierlambert

Thanks for the prompt reply !

You are right. The device was filtered. I am now removing from filter and re-testing.

Update: Re-tested and everything seems to work fine.
I will further try to use the signature device to see if it actually works inside the VM.

PS: I see no reason to filter tokens by default. Can we remove the DENY line for smartcards by default ?
We also need to add : DENY: Class=03 subclass=00 prot=00 # HID
as this class is used by some MSI motherboards for HID. Since rest of the HID are filtered, this should be added too for consistency sake.

xerxist

@stormi

So which page do need to refer my auditor to for all the patching that is done once the kernel is EOL?

gb.123

@olivierlambert

In continuation of my previous post, I also noticed that any changes to /etc/xensource/usb-policy.conf are reverted in case of updates. I also notices this reverting in case of restart (but need to confirm this after thorough testing as it may be one-time senario)

bufanda

@gb-123 In case of restart I never had it reverted only in case of update. After an update I just run an ansible playbook to add my whitelist entries again. sure it's a work around and some include file like usb-policy.conf.d/*conf would be nice to have.

gb.123

@bufanda

It reverted for me once in case of re-start but that has not happened the second time. That's why reported it as 'one-time' scenario.

I agree having usb-policy.conf.d/*conf would be nice to have.

For workaround, I am working on a script to over-write /etc/xensource/usb-policy.conf on every reboot (should take care of the updates as well). This is a crude way of doing it but this is just meant as a workaround rather than a long term solution which is adding the conf in something like usb-policy.conf.d/*conf as you mentioned.

gb.123

@olivierlambert @stormi

Any way to get the UUID of the Host using CLI ?
What I mean is not the list of hosts using xe host-list params=uuid but I only want to get the host uuid of the host on which the command is being run on.

Tristis Oris

@gb-123 cat /etc/xensource-inventory | grep -i installation_uuid

gb.123

@Tristis-Oris Thanks a Lot!

gb.123

For everyone who needs to ensure usb-policy.conf remains intact after update/reboot, I have posted a workaround script here.

Please note this is a workaround script only till a better implementation is done by the xcp-ng team.

xerxist

@xerxist said in XCP-ng 8.3 beta :

@stormi

So which page do need to refer my auditor to for all the patching that is done once the kernel is EOL?

Just in case I’ve asked Lawerence on Youtube what his thoughts are on promoting EOL products to his clients

ajpri1998

@xerxist

https://xcp-ng.org/docs/releases.html#all-releases

Latest LTS: XCP-ng 8.2

Using the Long Term Support version is relevant if:

    you want to be sure the system will stay stable
    you want to **have all security fixes** without doing major upgrades every year
    you want a predictable migration path on a longer timeframe
    you don't care about new features coming for the next years

LTS releases are supported for 5 years.

XCP-ng 8.2 still has about a year and 3 months left of support.

xerxist

@ajpri1998

That is not the point I’m trying to make.
The heart of the OS is going to be end of life December this year. You can probably plaster away but you need to keep track of everything for cve’s etc.. if you don’t want an auditor to trip on this. As they will because it’s end of life.

stormi

@xerxist The Linux kernel is not exactly the heart of XCP-ng. Xen is. Also, the threat model is different from that of a Linux distribution, because the main threat here comes from VMs (privilege escalation, information disclosure, DoS...), and this is taken very deep care of, at every level.

XCP-ng's management network being meant to be on a dedicated network, not exposed to direct attackers, makes network attacks a lower threat but of course doesn't negate it so it still is to be taken into account.

Your concerns are valid, especially regarding how to make an auditor accept that it is actually maintained for the scope of XCP-ng's needs, and we're looking how to document it.

archw

Yesterday, as I was about to walk out of the office for a deposition, someone walked in and said the connection to oen of the VM's was dead.

I opened up Idrac to the Dell host (Dell Inc. PowerEdge R540) and found a black screen unlike any I've seen before with XCP-NG; my vague recollection was a standard linux screen with "system" or something like that. I had twenty minutes to get to the deposition so I didn't have time to do normal debugging so I rebooted the host and watched as it did a normal reboot. It came back and all was well.

Now that the dust has cleared, this is my first chance to look into what happened. Where do I start? /var/log/xensource.log? /var/log/kern.log? Something else?

Thanks!