I connected an external 512 GB hard drive to the untrusted Qube. I was surprised to see that I could access it simultaneously from sys-usb and from the untrusted Qube. Is this normal? Is something broken?
I use debian minimal disposable for sys-usb, and debian for untrusted. I have not tried to replicate this event. The following photos shows that the two Qubes see and access the files on the same drive connected to untrusted Qube
The only insecure thing I see here is that you mounted any block device in sys-usb. That’s a no-go when Qubes.
Thanks for replying. I haven’t seen anywhere here on the forum or in the Qubes OS documentation that we shouldn’t connect the block devices. Also, I tried multiple times to connect the USB device, and I failed to get access the drive on the Qube. How do you connect a USB drive when it refuses to show up in a Qube?
This said, my main question remains. Is it normal for the same hard disk to be connected to two Qubes simultaneously, or is something broken in my system?
Out of curiosity I tried this. I did achieve a similar result.
Further, I assigned a USB drive from the usb-disks qube to vm1 qube using the usb drop-down then assigned a partition of that USB drive to vm2 qube. I was able to access the same partition from both vm1 qube & vm2 qube.
I didn’t know this was a feature and was quite surprised it happened.
This is not something I’d consider doing really but it seems to be an opportunity for “bad things” to happen.
Bump.
Doesn’t USB assignment work through USBIP? I’m assuming the sys-usb host has to read it in order to pass it along. When you attach a usb device to a VM I dont think it is as low level as say PCIe pass through. There is some arbitration and forwarding that has to go on continuously between host OS and guest OS
