Add missing transfer-length sanity check to the status-register completion handler to avoid leaking bits of uninitialised slab data to user space.
Fixes: 3f5429746d91 ("USB: Moschip 7840 USB-Serial Driver") Cc: stable stable@vger.kernel.org # 2.6.19 Cc: Paul B Schroeder pschroeder@uplogix.com Signed-off-by: Johan Hovold johan@kernel.org --- drivers/usb/serial/mos7840.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/usb/serial/mos7840.c b/drivers/usb/serial/mos7840.c index fdceb46d9fc6..b580b4c7fa48 100644 --- a/drivers/usb/serial/mos7840.c +++ b/drivers/usb/serial/mos7840.c @@ -468,6 +468,9 @@ static void mos7840_control_callback(struct urb *urb) }
dev_dbg(dev, "%s urb buffer size is %d\n", __func__, urb->actual_length); + if (urb->actual_length < 1) + goto out; + dev_dbg(dev, "%s mos7840_port->MsrLsr is %d port %d\n", __func__, mos7840_port->MsrLsr, mos7840_port->port_num); data = urb->transfer_buffer;