netdev - Re: [PATCH] net: qmi_wwan: add Dell DW5818, DW5819

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <87lgj1thg9.fsf@miraculix.mork.no>
Date:   Mon, 20 Nov 2017 10:41:58 +0100
From:   Bjørn Mork <bjorn@...k.no>
To:     Shrirang Bagul <shrirang.bagul@...onical.com>
Cc:     johan@...nel.org, netdev@...r.kernel.org,
        linux-usb@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] net: qmi_wwan: add Dell DW5818, DW5819

Shrirang Bagul <shrirang.bagul@...onical.com> writes:

> Dell Wireless 5819/5818 devices are re-branded Sierra Wireless MC74
> series modems which will by default boot with vid 0x413c and pid's
> 0x81cf, 0x81d0, 0x81d1,0x81d2. Along with qcserial, these modems support
> qmi_wwan on the usb interface #12.

NAK,

Interace #12 is MBIM, as shown by the device descriptors. Please provide
those descriptors and you will see that this interface is clearly a CDC
MBIM class interface.

Yes, I know these modems probe the control protocol so that you can make
QMI work on an MBIM control interface by sending it a QMI request as the
first messsage.  This is still wrong, abusing a quirky firmware
feature.

You need to reconfigure the modem for QMI using the Sierra specific AT
command or QMI request (tunneled in MBIM!) to properly switch it to QMI
mode, which will appear as a vendor specific interface number 8 (and 10
if you enable both QMI functions).

Bjørn