Due to the case that "requesttype == 0x01 && status <= 0"
isn't handled in r8712_usbctrl_vendorreq(),
"data" (drivers/staging/rtl8712/usb_ops.c:32)
will be returned without initialization.
When "tmpU1b" (drivers/staging/rtl8712/usb_intf.c:395)
is 0, mac[6] (usb_intf.c:394) won't be initialized,
which leads to accessing uninit-value on usb_intf.c:541.
Reported-and-tested-by: syzbot+6f5ecd144854c0d8580b@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Wang Cheng <wanngchenng@xxxxxxxxx>