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A recent change fixed device reference leaks when looking up drm platform device driver data during bind() but failed to remove a partial fix which had been added by commit80805b62ea("drm/mediatek: Fix kobject put for component sub-drivers"). This results in a reference imbalance on component bind() failures and on unbind() which could lead to a user-after-free. Make sure to only drop the references after retrieving the driver data by effectively reverting the previous partial fix. Note that holding a reference to a device does not prevent its driver data from going away so there is no point in keeping the reference. Fixes:1f403699c4("drm/mediatek: Fix device/node reference count leaks in mtk_drm_get_all_drm_priv") Reported-by: Sjoerd Simons <sjoerd@collabora.com> Closes: https://lore.kernel.org/r/20251003-mtk-drm-refcount-v1-1-3b3f2813b0db@collabora.com Cc: stable@vger.kernel.org Cc: Ma Ke <make24@iscas.ac.cn> Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Signed-off-by: Johan Hovold <johan@kernel.org> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Reviewed-by: Sjoerd Simons <sjoerd@collabora.com> Tested-by: Sjoerd Simons <sjoerd@collabora.com> Tested-by: Ritesh Raj Sarraf <ritesh.sarraf@collabora.com> Reviewed-by: CK Hu <ck.hu@mediatek.com> Link: https://patchwork.kernel.org/project/dri-devel/patch/20251006093937.27869-1-johan@kernel.org/ Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>