USB: idmouse: fix interface sanity checks

BugLink: https://bugs.launchpad.net/bugs/1857158
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>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

diff --git a/drivers/usb/misc/idmouse.c b/drivers/usb/misc/idmouse.c
index 20b0f91a5d9b6921e0afb1d33b1dc9bf34a6bae4..bb24527f3c7010854c9cf58a75e9c95ecf94cd5c 100644 (file)
--- a/drivers/usb/misc/idmouse.c
+++ b/drivers/usb/misc/idmouse.c
@@ -337,7 +337,7 @@ 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;