phy: phy-twl4030-usb: Fix possible use-after-free in twl4030_usb_remove()

This driver's remove path calls cancel_delayed_work(). However, that
function does not wait until the work function finishes. This means
that the callback function may still be running after the driver's
remove function has finished, which would result in a use-after-free.

Fix by calling cancel_delayed_work_sync(), which ensures that
the work is properly cancelled, no longer running, and unable
to re-schedule itself.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20210407092716.3270248-1-yangyingliang@huawei.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/phy/ti/phy-twl4030-usb.c b/drivers/phy/ti/phy-twl4030-usb.c
index 9887f908f5401a11e274159ab82b3c7272070709..812e5409d35958e75cf06a19efc1eec71124739a 100644 (file)
--- a/drivers/phy/ti/phy-twl4030-usb.c
+++ b/drivers/phy/ti/phy-twl4030-usb.c
@@ -779,7 +779,7 @@ static int twl4030_usb_remove(struct platform_device *pdev)
 
        usb_remove_phy(&twl->phy);
        pm_runtime_get_sync(twl->dev);
-       cancel_delayed_work(&twl->id_workaround_work);
+       cancel_delayed_work_sync(&twl->id_workaround_work);
        device_remove_file(twl->dev, &dev_attr_vbus);
 
        /* set transceiver mode to power on defaults */