From: Stuart Lee <stuart.lee@mediatek.com> stable inclusion from stable-v6.6.8 commit 03e63e497a404f444f5af25e120739da3a4f03ff category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I8ST59 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- 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> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> --- drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c index a033da279a94..80e34b39a6b1 100644 --- 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 drm_device *drm_dev, 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; } -- 2.20.1