USB: legousbtower: fix slab info leak at probe

commit 1d427be4a39defadda6dd8f4659bc17f7591740f upstream.

Make sure to check for short transfers when retrieving the version
information at probe to avoid leaking uninitialised slab data when
logging it.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20190919083039.30898-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/misc/legousbtower.c b/drivers/usb/misc/legousbtower.c
index 0ec9ee5..fc4b181 100644 (file)
--- a/drivers/usb/misc/legousbtower.c
+++ b/drivers/usb/misc/legousbtower.c
@@ -923,8 +923,10 @@ static int tower_probe (struct usb_interface *interface, const struct usb_device
                                  get_version_reply,
                                  sizeof(*get_version_reply),
                                  1000);
-       if (result < 0) {
-               dev_err(idev, "LEGO USB Tower get version control request failed\n");
+       if (result < sizeof(*get_version_reply)) {
+               if (result >= 0)
+                       result = -EIO;
+               dev_err(idev, "get version request failed: %d\n", result);
                retval = result;
                goto error;
        }