On Wed, Sep 9, 2020 at 9:17 PM Hector Martin "marcan"
<[email protected]> wrote:
>
>
>
> On September 10, 2020 12:02:34 PM GMT+09:00, Oliver Neukum <[email protected]>
> wrote:
> >Am Mittwoch, den 09.09.2020, 13:34 -0600 schrieb James Hilliard:
> >> This patch detects and reverses the effects of the malicious FTDI
> >> Windows driver version 2.12.00(FTDIgate).
> >
> >Hi,
> >
> >this raises questions.
> >Should we do this unconditionally without asking?
> >Does this belong into kernel space?
>
> I agree; this is very cute, but does it really need to be an automatic Linux
> feature? Presumably someone looking to fix a bricked FTDI chip can just run
> my script, and those who just want to use those chips with Linux already can
> since the driver binds to the zero PID.
Well for one your script is not easily useable with embedded platforms
like mine where I ran into this issue, I have no python2 interpreter
available in my production builds.
>
> I am deeply amused by the idea of Linux automatically fixing problems caused
> by malicious Windows drivers, but thinking objectively, I'm not sure if
> that's the right thing to do.
>From my understanding Linux fixing up hardware issues caused
by faulty/weird Windows drivers isn't exactly unusual.
>
> >
> >> +static int ftdi_repair_brick(struct usb_serial_port *port)
> >> +{
> >> + struct ftdi_private *priv = usb_get_serial_port_data(port);
> >> + int orig_latency;
> >> + int rv;
> >> + u16 *eeprom_data;
> >> + u16 checksum;
> >> + int eeprom_size;
> >> + int result;
> >> +
> >> + switch (priv->chip_type) {
> >> + case FT232RL:
> >> + eeprom_size = 0x40;
> >> + break;
> >> + default:
> >> + /* Unsupported for brick repair */
> >> + return 0;
> >> + }
> >> +
> >> + /* Latency timer needs to be 0x77 to unlock EEPROM programming */
> >> + if (priv->latency != 0x77) {
> >> + orig_latency = priv->latency;
> >> + priv->latency = 0x77;
> >> + rv = write_latency_timer(port);
> >> + priv->latency = orig_latency;
> >> + if (rv < 0)
> >> + return -EIO;
> >> + }
> >
> >Do you really want to change this without returning to the original?
> >
> > Regards
> > Oliver
>
> --
> Hector Martin "marcan" ([email protected])
> Public key: https://mrcn.st/pub
