rtlwifi: Detect misread of end-point count

In the unlikely event of a misread of the USB end point count, the driver
generates a divide fault. To prevent this, add a check of the value
returned by _rtl_usb_init(). In addition, add some logging to indicate
why the condition occurred.

Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/drivers/net/wireless/rtlwifi/usb.c b/drivers/net/wireless/rtlwifi/usb.c
index ffcf89fe45e4045f457b02d95c2ffc22c54151d5..b0eee0eb56790ef58deb7b0fe9311bb035beba00 100644 (file)
--- a/drivers/net/wireless/rtlwifi/usb.c
+++ b/drivers/net/wireless/rtlwifi/usb.c
@@ -346,9 +346,14 @@ static int _rtl_usb_init(struct ieee80211_hw *hw)
                         pep_desc->bEndpointAddress, pep_desc->wMaxPacketSize,
                         pep_desc->bInterval);
        }
-       if (rtlusb->in_ep_nums <  rtlpriv->cfg->usb_interface_cfg->in_ep_num)
-               return -EINVAL ;
-
+       if (rtlusb->in_ep_nums <  rtlpriv->cfg->usb_interface_cfg->in_ep_num) {
+               pr_err("Too few input end points found\n");
+               return -EINVAL;
+       }
+       if (rtlusb->out_ep_nums == 0) {
+               pr_err("No output end points found\n");
+               return -EINVAL;
+       }
        /* usb endpoint mapping */
        err = rtlpriv->cfg->usb_interface_cfg->usb_endpoint_mapping(hw);
        rtlusb->usb_mq_to_hwq =  rtlpriv->cfg->usb_interface_cfg->usb_mq_to_hwq;
@@ -976,6 +981,8 @@ int __devinit rtl_usb_probe(struct usb_interface *intf,
        }
        rtlpriv->cfg->ops->init_sw_leds(hw);
        err = _rtl_usb_init(hw);
+       if (err)
+               goto error_out;
        err = _rtl_usb_init_sw(hw);
        /* Init mac80211 sw */
        err = rtl_init_core(hw);