• Johan Hovold's avatar
    media: rtl28xxu: fix zero-length control request · 76f22c93
    Johan Hovold authored
    The direction of the pipe argument must match the request-type direction
    bit or control requests may fail depending on the host-controller-driver
    implementation.
    
    Control transfers without a data stage are treated as OUT requests by
    the USB stack and should be using usb_sndctrlpipe(). Failing to do so
    will now trigger a warning.
    
    The driver uses a zero-length i2c-read request for type detection so
    update the control-request code to use usb_sndctrlpipe() in this case.
    
    Note that actually trying to read the i2c register in question does not
    work as the register might not exist (e.g. depending on the demodulator)
    as reported by Eero Lehtinen <debiangamer2@gmail.com>.
    
    Reported-by: syzbot+faf11bbadc5a372564da@syzkaller.appspotmail.com
    Reported-by: default avatarEero Lehtinen <debiangamer2@gmail.com>
    Tested-by: default avatarEero Lehtinen <debiangamer2@gmail.com>
    Fixes: d0f232e8 ("[media] rtl28xxu: add heuristic to detect chip type")
    Cc: stable@vger.kernel.org      # 4.0
    Cc: Antti Palosaari <crope@iki.fi>
    Signed-off-by: default avatarJohan Hovold <johan@kernel.org>
    Signed-off-by: default avatarSean Young <sean@mess.org>
    Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+huawei@kernel.org>
    76f22c93
rtl28xxu.c 51.1 KB