[PATCH] drm/rockchip: dw_hdmi: cleanup drm encoder during unbind

From: Toby Chen
Date: Thu Mar 16 2023 - 20:51:53 EST


This fixes a use-after-free crash during rmmod.

The DRM encoder is embedded inside the larger rockchip_hdmi,
which is allocated with the component. The component memory
gets freed before the main drm device is destroyed. Fix it
by running encoder cleanup before tearing down its container.

Signed-off-by: Toby Chen <tobyc@xxxxxxxxxx>
---
drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c b/drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c
index 2f4b8f64cbad..8aa88e6c9e5a 100644
--- a/drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c
+++ b/drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c
@@ -642,6 +642,8 @@ static void dw_hdmi_rockchip_unbind(struct device *dev, struct device *master,
dw_hdmi_unbind(hdmi->hdmi);
clk_disable_unprepare(hdmi->ref_clk);

+ drm_encoder_cleanup(&hdmi->encoder.encoder);
+
regulator_disable(hdmi->avdd_1v8);
regulator_disable(hdmi->avdd_0v9);
}
--
2.25.1