USB: idmouse: fix interface sanity checks

commit 59920635b89d74b9207ea803d5e91498d39e8b69 upstream.

Make sure to use the current alternate setting when verifying the
interface descriptors to avoid binding to an invalid interface.

Failing to do so could cause the driver to misbehave or trigger a WARN()
in usb_submit_urb() that kernels with panic_on_warn set would choke on.

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/20191210112601.3561-4-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/misc/idmouse.c b/drivers/usb/misc/idmouse.c
index 9a67ae39185b8963caadd66e2edfb5117f5c4f17..9cf8a9b163361200f4522f3fe271db848dc7bd9a 100644 (file)
--- a/drivers/usb/misc/idmouse.c
+++ b/drivers/usb/misc/idmouse.c
@@ -342,7 +342,7 @@ static int idmouse_probe(struct usb_interface *interface,
        int result;
 
        /* check if we have gotten the data or the hid interface */
-       iface_desc = &interface->altsetting[0];
+       iface_desc = interface->cur_altsetting;
        if (iface_desc->desc.bInterfaceClass != 0x0A)
                return -ENODEV;