Subject: Re: [PATCH] net: usb: usbnet: restore usb%d name exception for local mac addresses

From: Jakub Kicinski <[email-masked]>
Date: Tue, 3 Dec 2024 18:13:04 -0800

On Tue, 3 Dec 2024 21:47:57 +0100 Andrew Lunn wrote:
> Are you saying the OTP or NVMEM has a locally administered MAC address
> stored in it? Is there a mechanism to change it? The point about
> locally administered MAC addresses is that they are locally
> administered.

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commit bfe9b9d2df669a57a95d641ed46eb018e204c6ce
Author: Kristian Evensen <[email-masked]>
Date:   Thu Jul 21 11:10:06 2016 +0200

    cdc_ether: Improve ZTE MF823/831/910 handling
    
    The firmware in several ZTE devices (at least the MF823/831/910
    modems/mifis) use OS fingerprinting to determine which type of device to
    export. In addition, these devices export a REST API which can be used to
    control the type of device. So far, on Linux, the devices have been seen as
    RNDIS or CDC Ether.
    
    When CDC Ether is used, devices of the same type are, as with RNDIS,
    exported with the same, bogus random MAC address. In addition, the devices
    (at least on all firmware revisions I have found) use the bogus MAC when
    sending traffic routed from external networks. And as a final feature, the
    devices sometimes export the link state incorrectly. There are also
    references online to several other ZTE devices displaying this behavior,
    with several different PIDs and MAC addresses.