USB tethering via new smartphone

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HI,

I’ve been trying use USB tethering with my Galaxy S23. I have been quite unsuccesful. I read a few threads on the forum. I didn’t get much wiser I’m affraid. One of them stated that in order to tether you need to have sys-usb and sys-net together as one. This isn’t true though.

I have been using USB tethering with Galaxy S7 for years now with sys-usb and sys-net seperate. You just connect the phone, add it to sys-net and it works like a charm.

S23 is weird though. Connect, add to sys-net, works until I actually open a browser and try to go to a site. I then get a “device disconnected” message. I read in Qubes USB troubleshooting that increasing the memory of the vm should hellp when this happens, because high bandwith devices require more memory. I raised the memory to 1GB. Didn’t help.

Also the device doesn’t seem to get properly picked up by Qubes. When I connect my S7, it shows a different device from when I switch it to USB tethering. Probably because it differentiates between the phone as a mass storage device and as a networking device. If I’m tethered and browsing and I turn tethering of it automatically switches back to mass storage device and disconnects the phone.

The S23 doesn’t do this though. It displays the same device no matter what the setting is, and It doesn’t disconnect if it’s connected and I turn USB tethering off. It just stays there looking like it’s connected when tethering isn’t even on. It feels really broken.

Feels like a driver issue. Can anyone confirm?

That same thread I read also mentioned that “newer phones” should use an ethernet dongle and do ethernet tethering instead. Is this my only option as far passing internet to my qubes machine via cable goes?

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There is known issue with new android devices connected using usb. Android MTP attach fails · Issue #6330 · QubesOS/qubes-issues · GitHub

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But now when I read it again after a long time it looks like it should work in your case.

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I forgot to mention, the S23 works just fine on windows machines. Tried it with two different cables as well. It’s only on Qubes that it malfunctions with either cable.

I’ll be reading up on this issue, thanks for the heads up.

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There are known issues with USB tethering on newer Android devices in Qubes OS. Ethernet tethering with a dongle is currently the recommended method.

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I’m not sure I follow. What are upstream issues?

Pixel 6a here.
Plug phone through USB cable. Have it disconnect data link. Unlock phone saith to tethering. Sys-usb discovered devices changes. Pass that device from sys-usb to sys-net. Works.

The changing of ID happens when you switch phone from chsrging/mtp to tethering. After that if should be stable and that device from sys-usb should stay when passed to sys-net.

If not, what are *sudo journalctl - f" output on both sys-usb and sys-net when you swi ch to tethering on sys-usb, and what does sys-net has to say when the device is passed to it.

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Upstream issues refer to problems outside your Pixel 6a causing the USB tethering instability.

Here’s what to check:

Phone logs: Run sudo journalctl -f on sys-usb and sys-net while switching tethering on to see any errors.

Tethering permission: Check if phone asks for tethering permission when switching modes.