6.6-stable review patch. If anyone has any objections, please let me know.
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From: Stuart Lee stuart.lee@mediatek.com
commit b6961d187fcd138981b8707dac87b9fcdbfe75d1 upstream.
Add error handling to check NULL input in mtk_drm_crtc_dma_dev_get function.
While display path is not configured correctly, none of crtc is established. So the caller of mtk_drm_crtc_dma_dev_get may pass input parameter *crtc as NULL, Which may cause coredump when we try to get the container of NULL pointer.
Fixes: cb1d6bcca542 ("drm/mediatek: Add dma dev get function") Signed-off-by: Stuart Lee stuart.lee@mediatek.com Cc: stable@vger.kernel.org Reviewed-by: AngeloGioacchino DEl Regno angelogioacchino.delregno@collabora.com Tested-by: Macpaul Lin macpaul.lin@mediatek.com Link: https://patchwork.kernel.org/project/dri-devel/patch/20231110012914.14884-2-... Signed-off-by: Chun-Kuang Hu chunkuang.hu@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)
--- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c @@ -885,7 +885,14 @@ static int mtk_drm_crtc_init_comp_planes
struct device *mtk_drm_crtc_dma_dev_get(struct drm_crtc *crtc) { - struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc); + struct mtk_drm_crtc *mtk_crtc = NULL; + + if (!crtc) + return NULL; + + mtk_crtc = to_mtk_crtc(crtc); + if (!mtk_crtc) + return NULL;
return mtk_crtc->dma_dev; }