can: peak_usb: add bounds check for USB channel index

can: peak_usb: add bounds check for USB channel index

The channel control index ctrl_idx is derived from rx->len which comes
directly from a device USB payload. The mask 0x0f allows values 0-15, but
the array size of usb_if->dev[] is only 2. Values 2-15 cause heap
out-of-bounds read, eventually causing kernel panic in the IRQ context.

Add bounds checking for ctrl_idx before the array access in both
pcan_usb_pro_handle_canmsg() and pcan_usb_pro_handle_error().

Fixes: d8a199355f8f ("can: usb: PEAK-System Technik PCAN-USB Pro specific part")
Signed-off-by: James Gao <jamesgao5@outlook.com>
Reviewed-by: Vincent Mailhol <mailhol@kernel.org>
Link: https://patch.msgid.link/TYWPR01MB8559DBAAAA6A7F410400329CF0012@TYWPR01MB8559.jpnprd01.prod.outlook.com
Cc: stable@kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>