[media] dvb_frontend: Fix possible read out of bounds

Check if index is within bounds _before_ accessing the value.

Signed-off-by: Ole Ernst <olebowle@gmx.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

drivers/media/dvb-core/dvb_frontend.c

@@ -1279,7 +1279,7 @@ static int dtv_property_process_get(struct dvb_frontend *fe,
 	switch(tvp->cmd) {
 	case DTV_ENUM_DELSYS:
 		ncaps = 0;
-		while (fe->ops.delsys[ncaps] && ncaps < MAX_DELSYS) {
+		while (ncaps < MAX_DELSYS && fe->ops.delsys[ncaps]) {
 			tvp->u.buffer.data[ncaps] = fe->ops.delsys[ncaps];
 			ncaps++;
 		}
@@ -1596,7 +1596,7 @@ static int dvbv5_set_delivery_system(struct dvb_frontend *fe,
 	 * supported
 	 */
 	ncaps = 0;
-	while (fe->ops.delsys[ncaps] && ncaps < MAX_DELSYS) {
+	while (ncaps < MAX_DELSYS && fe->ops.delsys[ncaps]) {
 		if (fe->ops.delsys[ncaps] == desired_system) {
 			c->delivery_system = desired_system;
 			dev_dbg(fe->dvb->device,
@@ -1628,7 +1628,7 @@ static int dvbv5_set_delivery_system(struct dvb_frontend *fe,
 	* of the desired system
 	*/
 	ncaps = 0;
-	while (fe->ops.delsys[ncaps] && ncaps < MAX_DELSYS) {
+	while (ncaps < MAX_DELSYS && fe->ops.delsys[ncaps]) {
 		if (dvbv3_type(fe->ops.delsys[ncaps]) == type)
 			delsys = fe->ops.delsys[ncaps];
 		ncaps++;
@@ -1703,7 +1703,7 @@ static int dvbv3_set_delivery_system(struct dvb_frontend *fe)
 	 * DVBv3 standard
 	 */
 	ncaps = 0;
-	while (fe->ops.delsys[ncaps] && ncaps < MAX_DELSYS) {
+	while (ncaps < MAX_DELSYS && fe->ops.delsys[ncaps]) {
 		if (dvbv3_type(fe->ops.delsys[ncaps]) != DVBV3_UNKNOWN) {
 			delsys = fe->ops.delsys[ncaps];
 			break;