USB: serial: garmin_gps: add sanity checking for data length

We must not process packets shorter than a packet ID

Signed-off-by: Oliver Neukum <[email protected]>
Reported-and-tested-by: [email protected]
Fixes: 1da177e ("Linux-2.6.12-rc2")
Cc: stable <[email protected]>
Signed-off-by: Johan Hovold <[email protected]>

Author: oneukum

drivers/usb/serial/garmin_gps.c

@@ -1138,8 +1138,8 @@ static void garmin_read_process(struct garmin_data *garmin_data_p,
 		   send it directly to the tty port */
 		if (garmin_data_p->flags & FLAGS_QUEUING) {
 			pkt_add(garmin_data_p, data, data_length);
-		} else if (bulk_data ||
-			   getLayerId(data) == GARMIN_LAYERID_APPL) {
+		} else if (bulk_data || (data_length >= sizeof(u32) &&
+				getLayerId(data) == GARMIN_LAYERID_APPL)) {
 
 			spin_lock_irqsave(&garmin_data_p->lock, flags);
 			garmin_data_p->flags |= APP_RESP_SEEN;