diff --git a/drivers/media/video/gspca/stv06xx/stv06xx_pb0100.c b/drivers/media/video/gspca/stv06xx/stv06xx_pb0100.c
index ac47b4c..75a5b9c 100644
--- a/drivers/media/video/gspca/stv06xx/stv06xx_pb0100.c
+++ b/drivers/media/video/gspca/stv06xx/stv06xx_pb0100.c
@@ -217,6 +217,8 @@
 
 	intf = usb_ifnum_to_if(sd->gspca_dev.dev, sd->gspca_dev.iface);
 	alt = usb_altnum_to_altsetting(intf, sd->gspca_dev.alt);
+	if (!alt)
+		return -ENODEV;
 	packet_size = le16_to_cpu(alt->endpoint[0].desc.wMaxPacketSize);
 
 	/* If we don't have enough bandwidth use a lower framerate */