From dde58cfcc3b6dd2f160ffd355f76ae526155a4df Mon Sep 17 00:00:00 2001 From: David Herrmann Date: Mon, 5 Sep 2011 18:45:28 +0200 Subject: [PATCH] HID: wacom: Fix error path of power-supply initialization power_supply_unregister() must not be called if power_supply_register() failed. The wdata->psy.dev pointer may point to invalid memory after a failed power_supply_register() and hence wacom_remove() will fail while calling power_supply_unregister(). This changes the wacom_probe function to fail if it cannot register the power_supply devices. If we would want to keep the previous behaviour we had to keep some flag about the power_supply state and check it on wacom_remove, but this seems inappropriate here. Hence, we simply fail, too, if power_supply_register fails. Signed-off-by: David Herrmann Signed-off-by: Jiri Kosina --- drivers/hid/hid-wacom.c | 21 +++++++++------------ 1 file changed, 9 insertions(+), 12 deletions(-) diff --git a/drivers/hid/hid-wacom.c b/drivers/hid/hid-wacom.c index 0688832..f66a597 100644 --- a/drivers/hid/hid-wacom.c +++ b/drivers/hid/hid-wacom.c @@ -353,11 +353,7 @@ static int wacom_probe(struct hid_device *hdev, if (ret) { hid_warn(hdev, "can't create sysfs battery attribute, err: %d\n", ret); - /* - * battery attribute is not critical for the tablet, but if it - * failed then there is no need to create ac attribute - */ - goto move_on; + goto err_battery; } wdata->ac.properties = wacom_ac_props; @@ -371,14 +367,8 @@ static int wacom_probe(struct hid_device *hdev, if (ret) { hid_warn(hdev, "can't create ac battery attribute, err: %d\n", ret); - /* - * ac attribute is not critical for the tablet, but if it - * failed then we don't want to battery attribute to exist - */ - power_supply_unregister(&wdata->battery); + goto err_ac; } - -move_on: #endif hidinput = list_entry(hdev->inputs.next, struct hid_input, list); input = hidinput->input; @@ -416,6 +406,13 @@ move_on: return 0; +#ifdef CONFIG_HID_WACOM_POWER_SUPPLY +err_ac: + power_supply_unregister(&wdata->battery); +err_battery: + device_remove_file(&hdev->dev, &dev_attr_speed); + hid_hw_stop(hdev); +#endif err_free: kfree(wdata); return ret; -- 2.7.4