uwb: i1480-dfu: fix NULL-deref at probe

BugLink: http://bugs.launchpad.net/bugs/1677589
commit 4ce362711d78a4999011add3115b8f4b0bc25e8c upstream.

Make sure to check the number of endpoints to avoid dereferencing a
NULL-pointer should a malicious device lack endpoints.

Note that the dereference happens in the cmd and wait_init_done
callbacks which are called during probe.

Fixes: 1ba47da52712 ("uwb: add the i1480 DFU driver")
Cc: Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
Cc: David Vrabel <david.vrabel@csr.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>

diff --git a/drivers/uwb/i1480/dfu/usb.c b/drivers/uwb/i1480/dfu/usb.c
index 2bfc846ac071341ace37aa50dc126fc5b08a519f..6345e85822a42457f11c607effb3fbb66ce8c89f 100644 (file)
--- a/drivers/uwb/i1480/dfu/usb.c
+++ b/drivers/uwb/i1480/dfu/usb.c
@@ -362,6 +362,9 @@ int i1480_usb_probe(struct usb_interface *iface, const struct usb_device_id *id)
                                 result);
        }
 
+       if (iface->cur_altsetting->desc.bNumEndpoints < 1)
+               return -ENODEV;
+
        result = -ENOMEM;
        i1480_usb = kzalloc(sizeof(*i1480_usb), GFP_KERNEL);
        if (i1480_usb == NULL) {