[media] gp8psk: don't go past the buffer size

Add checks to avoid going out of the buffer.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

diff --git a/drivers/media/usb/dvb-usb/gp8psk.c b/drivers/media/usb/dvb-usb/gp8psk.c
index 807f562..adfd764 100644 (file)
--- a/drivers/media/usb/dvb-usb/gp8psk.c
+++ b/drivers/media/usb/dvb-usb/gp8psk.c
@@ -60,6 +60,9 @@ int gp8psk_usb_in_op(struct dvb_usb_device *d, u8 req, u16 value, u16 index, u8
        struct gp8psk_state *st = d->priv;
        int ret = 0,try = 0;
 
+       if (blen > sizeof(st->data))
+               return -EIO;
+
        if ((ret = mutex_lock_interruptible(&d->usb_mutex)))
                return ret;
 
@@ -98,6 +101,9 @@ int gp8psk_usb_out_op(struct dvb_usb_device *d, u8 req, u16 value,
        deb_xfer("out: req. %x, val: %x, ind: %x, buffer: ",req,value,index);
        debug_dump(b,blen,deb_xfer);
 
+       if (blen > sizeof(st->data))
+               return -EIO;
+
        if ((ret = mutex_lock_interruptible(&d->usb_mutex)))
                return ret;
 
@@ -151,6 +157,11 @@ static int gp8psk_load_bcm4500fw(struct dvb_usb_device *d)
                        err("failed to load bcm4500 firmware.");
                        goto out_free;
                }
+               if (buflen > 64) {
+                       err("firmare chunk size bigger than 64 bytes.");
+                       goto out_free;
+               }
+
                memcpy(buf, ptr, buflen);
                if (dvb_usb_generic_write(d, buf, buflen)) {
                        err("failed to load bcm4500 firmware.");