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.
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.
>
>> +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
