From: Johan Hovold johan@kernel.org
[ Upstream commit de37458f8c2bfc465500a1dd0d15dbe96d2a698c ]
The set-led command is eight bytes long and starts with a command byte followed by six bytes of RGB data and ends with a byte encoding a frequency (see iuu_led() and iuu_rgbf_fill_buffer()).
The led activity helpers had a few long-standing bugs which corrupted the command packets by inserting a second command byte and thereby offsetting the RGB data and dropping the frequency in non-xmas mode.
In xmas mode, a related off-by-one error left the frequency field uninitialised.
Fixes: 60a8fc017103 ("USB: add iuu_phoenix driver") Reported-by: George Spelvin lkml@sdf.org Link: https://lore.kernel.org/r/20200716085056.31471-1-johan@kernel.org Reviewed-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Johan Hovold johan@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/usb/serial/iuu_phoenix.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-)
diff --git a/drivers/usb/serial/iuu_phoenix.c b/drivers/usb/serial/iuu_phoenix.c index e287fd52c575b..734f18d0a7f73 100644 --- a/drivers/usb/serial/iuu_phoenix.c +++ b/drivers/usb/serial/iuu_phoenix.c @@ -353,10 +353,11 @@ static void iuu_led_activity_on(struct urb *urb) struct usb_serial_port *port = urb->context; int result; char *buf_ptr = port->write_urb->transfer_buffer; - *buf_ptr++ = IUU_SET_LED; + if (xmas) { - get_random_bytes(buf_ptr, 6); - *(buf_ptr+7) = 1; + buf_ptr[0] = IUU_SET_LED; + get_random_bytes(buf_ptr + 1, 6); + buf_ptr[7] = 1; } else { iuu_rgbf_fill_buffer(buf_ptr, 255, 255, 0, 0, 0, 0, 255); } @@ -374,13 +375,14 @@ static void iuu_led_activity_off(struct urb *urb) struct usb_serial_port *port = urb->context; int result; char *buf_ptr = port->write_urb->transfer_buffer; + if (xmas) { iuu_rxcmd(urb); return; - } else { - *buf_ptr++ = IUU_SET_LED; - iuu_rgbf_fill_buffer(buf_ptr, 0, 0, 255, 255, 0, 0, 255); } + + iuu_rgbf_fill_buffer(buf_ptr, 0, 0, 255, 255, 0, 0, 255); + usb_fill_bulk_urb(port->write_urb, port->serial->dev, usb_sndbulkpipe(port->serial->dev, port->bulk_out_endpointAddress),