phy: tegra: xusb: Clear the driver reference in usb-phy dev

For the dual-role port, it will assign the phy dev to usb-phy dev and
use the port dev driver as the dev driver of usb-phy.

When we try to destroy the port dev, it will destroy its dev driver
as well. But we did not remove the reference from usb-phy dev. This
might cause the use-after-free issue in KASAN.

Fixes: e8f7d2f409a1 ("phy: tegra: xusb: Add usb-phy support")
Cc: stable@vger.kernel.org
Signed-off-by: EJ Hsu <ejh@nvidia.com>
Signed-off-by: Haotien Hsu <haotienh@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Link: https://lore.kernel.org/r/20230609062932.3276509-1-haotienh@nvidia.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

diff --git a/drivers/phy/tegra/xusb.c b/drivers/phy/tegra/xusb.c
index b55d4e9..b5bad46 100644 (file)
--- a/drivers/phy/tegra/xusb.c
+++ b/drivers/phy/tegra/xusb.c
@@ -568,6 +568,7 @@ static void tegra_xusb_port_unregister(struct tegra_xusb_port *port)
                usb_role_switch_unregister(port->usb_role_sw);
                cancel_work_sync(&port->usb_phy_work);
                usb_remove_phy(&port->usb_phy);
+               port->usb_phy.dev->driver = NULL;
        }
 
        if (port->ops->remove)