V4L/DVB (7758): ivtv: fix oops when itv->speed == 0 and VIDEO_CMD_PLA…

…Y is called

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

drivers/media/video/ivtv/ivtv-ioctl.c

@@ -243,20 +243,31 @@ static int ivtv_validate_speed(int cur_speed, int new_speed)
 	int fact = new_speed < 0 ? -1 : 1;
 	int s;
 
-	if (new_speed < 0) new_speed = -new_speed;
-	if (cur_speed < 0) cur_speed = -cur_speed;
+	if (cur_speed == 0)
+		cur_speed = 1000;
+	if (new_speed < 0)
+		new_speed = -new_speed;
+	if (cur_speed < 0)
+		cur_speed = -cur_speed;
 
 	if (cur_speed <= new_speed) {
-		if (new_speed > 1500) return fact * 2000;
-		if (new_speed > 1000) return fact * 1500;
+		if (new_speed > 1500)
+			return fact * 2000;
+		if (new_speed > 1000)
+			return fact * 1500;
 	}
 	else {
-		if (new_speed >= 2000) return fact * 2000;
-		if (new_speed >= 1500) return fact * 1500;
-		if (new_speed >= 1000) return fact * 1000;
-	}
-	if (new_speed == 0) return 1000;
-	if (new_speed == 1 || new_speed == 1000) return fact * new_speed;
+		if (new_speed >= 2000)
+			return fact * 2000;
+		if (new_speed >= 1500)
+			return fact * 1500;
+		if (new_speed >= 1000)
+			return fact * 1000;
+	}
+	if (new_speed == 0)
+		return 1000;
+	if (new_speed == 1 || new_speed == 1000)
+		return fact * new_speed;
 
 	s = new_speed;
 	new_speed = 1000 / new_speed;