uwb: init beacon cache entry before registering uwb device

Make sure the uwb_dev->bce entry is set before calling uwb_dev_add in
uwbd_dev_onair so that usermode will only see the device after it is
properly initialized.  This fixes a kernel panic that can occur if
usermode tries to access the IEs sysfs attribute of a UWB device before
the driver has had a chance to set the beacon cache entry.

Signed-off-by: Thomas Pugliese <thomas.pugliese@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/uwb/lc-dev.c b/drivers/uwb/lc-dev.c
index 80079b8..d0303f0 100644 (file)
--- a/drivers/uwb/lc-dev.c
+++ b/drivers/uwb/lc-dev.c
@@ -431,16 +431,19 @@ void uwbd_dev_onair(struct uwb_rc *rc, struct uwb_beca_e *bce)
        uwb_dev->mac_addr = *bce->mac_addr;
        uwb_dev->dev_addr = bce->dev_addr;
        dev_set_name(&uwb_dev->dev, "%s", macbuf);
+
+       /* plug the beacon cache */
+       bce->uwb_dev = uwb_dev;
+       uwb_dev->bce = bce;
+       uwb_bce_get(bce);               /* released in uwb_dev_sys_release() */
+
        result = uwb_dev_add(uwb_dev, &rc->uwb_dev.dev, rc);
        if (result < 0) {
                dev_err(dev, "new device %s: cannot instantiate device\n",
                        macbuf);
                goto error_dev_add;
        }
-       /* plug the beacon cache */
-       bce->uwb_dev = uwb_dev;
-       uwb_dev->bce = bce;
-       uwb_bce_get(bce);               /* released in uwb_dev_sys_release() */
+
        dev_info(dev, "uwb device (mac %s dev %s) connected to %s %s\n",
                 macbuf, devbuf, rc->uwb_dev.dev.parent->bus->name,
                 dev_name(rc->uwb_dev.dev.parent));
@@ -448,6 +451,8 @@ void uwbd_dev_onair(struct uwb_rc *rc, struct uwb_beca_e *bce)
        return;
 
 error_dev_add:
+       bce->uwb_dev = NULL;
+       uwb_bce_put(bce);
        kfree(uwb_dev);
        return;
 }